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Interstellar Dust From Our Solar System’s Birth
By Judith E Braffman-Miller
Our Sun formed from the jumbled leftovers of the nuclear-fusing furnaces of earlier generations of stars–and like other stars, it was born within a dense, frigid blob cradled within one of the giant, dark, interstellar molecular clouds that float through our Milky Way Galaxy in huge numbers. This especially dense blob eventually collapsed under its own gravitational pull to create our brilliant baby Star. Most of the gas and dust that swirls within beautiful, ghostly molecular clouds originates from the stellar furnaces of earlier generations of doomed stars, that either blasted themselves to shreds in a supernova explosion, or (if they were smaller stars), more gently puffed their outer gaseous layers into interstellar space. From this lingering material, left as a legacy by a multitude of long-dead stars, new stars were born from the wreckage of previous stellar generations. In June 2018, a team of scientists announced their new discovery that certain interplanetary dust particles are primordial leftovers from the initial birth of our Solar System.
The team of scientists, led by University of Hawaii at Manoa (UH Manoa) School of Ocean and Earth Science and Technology (SOEST) researcher Dr. Hope Ishii, was funded by NASA’s Cosmochemistry, Emerging Worlds and Laboratory Analysis of Returned Samples Programs and was enabled, in part, by the Advanced Electron Microscopy Center at the University of Hawaii. Portions of the research were also performed at national user facilities at the Molecular Foundry and the Advanced Light Source at Lawrence Berkeley National Laboratory, supported by the U.S. Department of Energy.
The first solids out of which our Solar System emerged were composed mostly of amorphous silicate, carbon and ices. This primordial dust was almost entirely destroyed and altered by processes that eventually resulted in the formation of planets. Surviving samples of pre-solar dust are probably preserved in comets. Comets are small, cold objects that inhabit our Solar System’s outer limits: the Kuiper Belt, Scattered Disk, and Oort Cloud. Here, in our Solar System’s deep freeze, the icy and dusty dancing comet nuclei preserve, in their frozen hearts, the mysterious ancient dust of our baby Solar System. Comets formed in the outer fringes of the original solar nebula.
Tucked within a relatively obscure class of interplanetary dust particles (IDPs), believed to originate from comets, are very small glassy grains dubbed GEMS, or glass embedded with metal and sulfides that are typically only tens to hundreds of nanometers in diameter. This is less than 1/100th the thickness of a strand of human hair.
Although we often think of vast regions of interstellar space as being empty, this is not the case. Much of the space between stars is brimming with atomic and molecular gas–primarily hydrogen and helium–and extremely tiny tidbits of solid particles or dust. This dust is composed mainly of silicon, oxygen, and carbon. In certain regions the gas and dust density is very low.
In the secretive depths of enormous, dark molecular clouds–that contain this gas and dust–extremely fragile threads of material slowly merge, clump, and grow for hundreds of thousands of years. Then, mercilessly squeezed by the relentless crush of gravity, the hydrogen atoms within these clumps dramatically and suddenly fuse. This initial episode of nuclear fusion lights a baby star’s fire that will last for as long as the new star “lives”.
All stars, regardless of their mass, are gigantic spheres of primarily hydrogen gas. The Big Bang birth of the Universe, about 13.8 billion years ago, produced only the lightest atomic elements–hydrogen, helium, and trace quantities of lithium (Big Bang Nucleosynthesis). All of the atomic elements heavier than helium–called metals by astronomers–are produced in the nuclear-fusing cores of the Universe’s stars (Stellar Nucleosynthesis) or, in the case of the heaviest atomic elements of all (such as gold and uranium), in the supernova explosion that heralds the death of a massive star.
Stars “live” on the hydrogen-burning main-sequence of the Hertzsprung-Russell Diagram of Stellar Evolution as a result of the process of nuclear fusion–that is, by producing increasingly heavier and heavier atomic elements out of lighter ones. The fusion process begins with hydrogen and, in the case of massive stars, continues until the star has a core of iron. Iron cannot be used as fuel, and so that’s the end of the massive star. Smaller stars, like our Sun, are not able to continue fusion all the way up to the point that they possess a core of iron. However, they do fuse lighter atomic elements from their supply of hydrogen fuel, such as carbon and oxygen. This is why solitary small stars, like our Sun, don’t “go supernova”.
Nuclear fusion creates radiation pressure that tries to push everything outward and away from the star, while gravity does the opposite and tries to pull everything in and towards the star. The eternal battle between radiation pressure and gravity keeps a main-sequence star bouncy–until it has managed to burn its entire necessary supply of nuclear-fusing fuel, which marks the end of the long stellar road for the doomed star. At that unfortunate point, gravity wins the war against its arch-enemy, radiation pressure, and the star is ready to make its final farewell performance to the Cosmos. If the star is massive, it will blow itself to smithereens in a brilliant supernova blast, that will send its newly forged supply of freshly fused metals screaming out into interstellar space. For a short time, this explosion can be so bright that it outshines its entire host galaxy. Massive stars, that have exploded in the furious tantrum of a fiery supernova, leave either a neutron star or stellar mass black hole behind as testimony of their former existence.
Small stars–like our Sun–go much more “gentle into that good night”, and puff their metals out into interstellar space, as they leave their relic core behind in the form of a dense stellar corpse termed a white dwarf. The new white dwarf is born surrounded by the multicolored shimmering, glimmering shroud of what was once its small progenitor star’s outer gaseous layers. Indeed, these glowing candy-colored stellar shrouds are so beautiful that they are frequently referred to as the “butterflies of the Universe.” This will be our Sun’s fate.
Today our Sun is a small, middle-aged star. Stars of our Sun’s mass live for approximately 10 billion years on the hydrogen-burning main-sequence. Since our Sun is only 4.56 billion years old, it will not have its grand finale for about another 5 billion years. As stars go, our Sun is rather ordinary. There are eight major planets and a rich assortment of other objects orbiting our Sun, which is located in the far suburbs of our majestic spiral Milky Way. If we trace the history of atoms on our planet today back about 8 billion years, we would likely find them spread all over our Galaxy. Some of these formerly widely dispersed atoms exist in a single strand of human genetic material (DNA)–even though, in more ancient times, they were born within alien stars inhabiting our young Milky Way.
Our solitary Sun was born with company, just like billions of other stars that do their mesmerizing stellar dance within our Galaxy. Our own Star was likely born a member of a dense open cluster along with thousands of other glittering stellar siblings. However, our Sun’s stellar sisters have gone missing, wandering off to more remote regions of our Milky Way–and there well may be as many as 3,500 of these long-lost solar kin.
All stars, our own included, are born surrounded by a whirling disk composed of gas and dust called a protoplanetary accretion disk. These whirling, nurturing gaseous rings, that linger around newborn stars, contain the necessary ingredients from which a family of planets can emerge. Astronomers have observed many protoplanetary accretion disks circling distant young stars, and these disks form at about the same time that the new star (protostar) is born within its veiling natal cloud.
Most of the material of the collapsing, dense blob that is cradled within the giant, dark molecular cloud, gathers at the center, and eventually evolves into a protostar. The leftover gas and dust becomes the surrounding accretion disk, from which planets, moons, and smaller objects eventually accrete. These disks are both extremely hot and massive, and they can linger around the young star for as long as 10 million years.
By the time a fiery baby star, that is similar to our own Sun, reaches what is called the T Tauri stage of development, the disk has become both cooler and thinner. A T Tauri star is a young variable star, that will eventually become a small star that is similar to our Sun. T Tauris are very active at the tender age of about 10 million years, and these stellar toddlers sport large diameters that are several times greater than that of our Sun–but they will shrink. Unlike human children, T Tauris shrink as they grow older. By the time the stellar tot has reached the T Tauri stage, less volatile materials have started to condense close to the center of the encircling accretion disk, creating very fine and sticky dust motes. The delicate dust particles contain crystalline silicates.
The sticky dust motes collide with one another in the crowded disk environment, and “glue” themselves to one another–forming ever larger, and larger, and larger objects–from pebble size, to boulder size, to mountain size to moon size, to planet size. These growing bodies evolve into planetesimals–the primordial building blocks of planets. Planetesimals constitute an abundant population within the disk, and some of them can linger around their star for billions of years. In our own Solar System, the asteroids and comets are what is left of this ancient population of planetesimals. The asteroids, that are mostly found in the Main Asteroid Belt between Mars and Jupiter, are akin to the rocky and metallic planetesimals that constructed the four solid, inner planets: Mercury, Venus, Earth, and Mars. In a similar way, comets are the relics of the icy, dirty planetesimals that formed the quartet of outer Solar System gaseous behemoths: Jupiter, Saturn, Uranus, and Neptune.
Interstellar Dust Tells Its Ancient Tale
Dr. Ishii and her colleagues used transmission electron microscopy to make maps of the element distributions and found that the glassy grains (GEMS) are composed of even smaller subgrains that merged together in a different environment–probably before the formation of their parent-comet nucleus.These glassy grains are also encapsulated by carbon of a different type than the carbon that creates a matrix gluing together GEMS and other components of cometary dust.
The forms of carbon that coat the subgrains, and create the matrix within these particles, tends to fall apart even when only slightly warmed up. This means that the GEMS could not have been born in the searing-hot inner solar nebula close to the intense fiery heat of our newborn Sun. Therefore, they must have formed in a frigid, radiation-rich environment. This type of environment would have likely existed in the outer solar nebula or within the swirling folds of the natal pre-solar molecular cloud.
“Our observations suggest that these exotic grains represent surviving pre-solar interstellar dust that formed the very building blocks of planets and stars. If we have at our fingertips the starting materials of planet formation from 4.6 billion years ago, that is thrilling and makes possible a deeper understanding of the processes that formed and have since altered them,” Dr. Ishii explained in a June 12, 2018 University of Hawaii Press Release.
In the future, Dr. Ishii and her team plan to go on the hunt for additional comet dust particles, especially those that were well-protected during their dive down through the Earth’s atmosphere. The team wants to increase scientific understanding of the distribution of carbon hiding within GEMS, as well as the size distribution of GEMS subgrains.
“This is an example of research that seeks to satisfy the human urge to understand our world’s origins and serves the people of Hawaii by boosting our reputation for excellence in space science and as a training ground for our students to be engaged in exciting science,” Dr. Ishii continued to comment.
Judith E. Braffman-Miller is a writer and astronomer whose articles have been published since 1981 in various magazines, journals, and newspapers. Although she has written on a variety of topics, she particularly loves writing about astronomy because it gives her the opportunity to communicate to others some of the many wonders of her field. Her first book, “Wisps, Ashes, and Smoke,” will be published soon.
Article Source: http://EzineArticles.com/expert/Judith_E_Braffman-Miller/1378365 | <urn:uuid:3a34d6a0-6215-42a2-935b-3e65a44bc9c9> | 3.890625 | 2,794 | Nonfiction Writing | Science & Tech. | 40.041698 | 95,593,103 |
chmod, fchmod, fchmodat - change permissions of a file
int chmod(const char *pathname, mode_t mode);
int fchmod(int fd, mode_t mode);
#include <fcntl.h> /* Definition of AT_* constants */
int fchmodat(int dirfd, const char *pathname, mode_t mode, int flags);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)
Since glibc 2.24:
_POSIX_C_SOURCE >= 199309L
Glibc 2.19 to 2.23
Glibc 2.16 to 2.19:
_BSD_SOURCE || _POSIX_C_SOURCE
Glibc 2.12 to 2.16:
_BSD_SOURCE || _XOPEN_SOURCE >= 500 ||
_POSIX_C_SOURCE >= 200809L
Glibc 2.11 and earlier:
_BSD_SOURCE || _XOPEN_SOURCE >= 500
- Since glibc 2.10:
- _POSIX_C_SOURCE >= 200809L
- Before glibc 2.10:
() and fchmod
() system calls change a files mode bits.
(The file mode consists of the file permission bits plus the set-user-ID,
set-group-ID, and sticky bits.) These system calls differ only in how the file
- chmod() changes the mode of the file specified whose
pathname is given in pathname, which is dereferenced if it is a
- fchmod() changes the mode of the file referred to by
the open file descriptor fd.
The new file mode is specified in mode
, which is a bit mask created by
ORing together zero or more of the following:
- S_ISUID (04000)
- set-user-ID (set process effective user ID on
- S_ISGID (02000)
- set-group-ID (set process effective group ID on
execve(2); mandatory locking, as described in fcntl(2); take
a new file's group from parent directory, as described in chown(2)
- S_ISVTX (01000)
- sticky bit (restricted deletion flag, as described in
- S_IRUSR (00400)
- read by owner
- S_IWUSR (00200)
- write by owner
- S_IXUSR (00100)
- execute/search by owner ("search" applies for
directories, and means that entries within the directory can be
- S_IRGRP (00040)
- read by group
- S_IWGRP (00020)
- write by group
- S_IXGRP (00010)
- execute/search by group
- S_IROTH (00004)
- read by others
- S_IWOTH (00002)
- write by others
- S_IXOTH (00001)
- execute/search by others
The effective UID of the calling process must match the owner of the file, or
the process must be privileged (Linux: it must have the CAP_FOWNER
If the calling process is not privileged (Linux: does not have the
capability), and the group of the file does not match the
effective group ID of the process or one of its supplementary group IDs, the
bit will be turned off, but this will not cause an error to be
As a security measure, depending on the filesystem, the set-user-ID and
set-group-ID execution bits may be turned off if a file is written. (On Linux,
this occurs if the writing process does not have the CAP_FSETID
capability.) On some filesystems, only the superuser can set the sticky bit,
which may have a special meaning. For the sticky bit, and for set-user-ID and
set-group-ID bits on directories, see inode(7)
On NFS filesystems, restricting the permissions will immediately influence
already open files, because the access control is done on the server, but open
files are maintained by the client. Widening the permissions may be delayed
for other clients if attribute caching is enabled on them.
() system call operates in exactly the same way as
(), except for the differences described here.
If the pathname given in pathname
is relative, then it is interpreted
relative to the directory referred to by the file descriptor dirfd
(rather than relative to the current working directory of the calling process,
as is done by chmod
() for a relative pathname).
is relative and dirfd
is the special value
, then pathname
is interpreted relative to the current
working directory of the calling process (like chmod
is absolute, then dirfd
can either be 0, or include the following flag:
- If pathname is a symbolic link, do not dereference
it: instead operate on the link itself. This flag is not currently
for an explanation of the need for fchmodat
On success, zero is returned. On error, -1 is returned, and errno
Depending on the filesystem, errors other than those listed below can be
The more general errors for chmod
() are listed below:
- Search permission is denied on a component of the path
prefix. (See also path_resolution(7).)
- pathname points outside your accessible address
- An I/O error occurred.
- Too many symbolic links were encountered in resolving
- pathname is too long.
- The file does not exist.
- Insufficient kernel memory was available.
- A component of the path prefix is not a directory.
- The effective UID does not match the owner of the file, and
the process is not privileged (Linux: it does not have the
- The file is marked immutable or append-only. (See
- The named file resides on a read-only filesystem.
The general errors for fchmod
() are listed below:
- The file descriptor fd is not valid.
- See above.
- See above.
- See above.
The same errors that occur for chmod
() can also occur for
(). The following additional errors can occur for
- dirfd is not a valid file descriptor.
- Invalid flag specified in flags.
- pathname is relative and dirfd is a file
descriptor referring to a file other than a directory.
- flags specified AT_SYMLINK_NOFOLLOW, which is
() was added to Linux in kernel 2.6.16; library support was added
to glibc in version 2.4.
(): 4.4BSD, SVr4, POSIX.1-2001i, POSIX.1-2008.
The GNU C library fchmodat
() wrapper function implements the
POSIX-specified interface described in this page. This interface differs from
the underlying Linux system call, which does not
have a flags
On older kernels where fchmodat
() is unavailable, the glibc wrapper
function falls back to the use of chmod
(). When pathname
relative pathname, glibc constructs a pathname based on the symbolic link in
that corresponds to the dirfd
This page is part of release 4.16 of the Linux man-pages
description of the project, information about reporting bugs, and the latest
version of this page, can be found at | <urn:uuid:4c741453-d6d1-4f66-b016-b0a19d178f7d> | 2.90625 | 1,637 | Documentation | Software Dev. | 52.422275 | 95,593,111 |
The iDiv Ecotron, a central experimental platform of the DFG Research Centre iDiv, was officially launched during a ceremony last Wednesday. Researchers will use this unique facility to better understand the consequences of species loss. The iDiv Ecotron will enable investigations into the interactions within food webs among plants, animals, microbes and the soil under controlled conditions in 24 experimental chambers. Over 3.7 million euros have been invested into this modern platform, which is operated jointly by the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig and the Helmholtz Centre for Environmental Research (UFZ).
It is anticipated to bridge the gap between simple laboratory experiments and complex ecosystem approaches. The iDiv Ecotron enriches the field research station of the UFZ in Bad Lauchstädt, which is gaining national and international stature as an ecological research station due to the cooperation between the UFZ and iDiv.
Basic research of high societal relevance
Many human activities are causing species loss. According to a number of estimates, numerous species of invertebrates are becoming extinct daily. Yet, what does this mean for the functioning of ecosystems? The following is clear: high species diversity has a positive effect on numerous functions of ecosystems. Thus, for example, a large number of plant species increases the production of biomass such as hay and wood, or the storage of climate-impacting carbon in the soil. This is demonstrated by experiments from various research platforms such as the Jena Experiment or the Biodiversity Exploratories of the German Research Foundation, which also involve researchers from iDiv and UFZ.
Little is known, however, about the role of small herbivores (e.g. snails or caterpillars), predators (e.g. ladybirds or spiders) or animals that live underground (e.g. earthworms or nematodes) and micro-organisms (e.g. bacteria or fungi). We know that these organisms play an important role in the food web and have a positive influence on many functions of ecosystems. Pollinators like bees and bumblebees, for example, are indispensable for the reproduction of many plant species. Other insects such as ants help plants spread their seeds. Decomposers such as earthworms and soil micro-organisms recycle nutrients for plant growth.
But such dependencies between different food web components have, so far, been investigated in closer detail in only a few cases. Researchers plan to use the new research platform to change this. The iDiv Ecotron has been designed to find out how the disappearance of species at different locations of the food web impacts the functioning of ecosystems. This fundamental biological research has far-reaching economic relevance: functioning ecosystems are the basis for a series of so-called ecosystem services such as the provision of clean drinking water, food, and energy sources, which nature provides to people. UFZ scientists estimate that insects benefit the global economy in the realm of approximately 150 billion euros per year, just by pollinating cultivated plants in agriculture. Until now, it has been very difficult to make such estimates for other animals or micro-organisms.
How many losses can ecosystems cope with?
If many species are present, this has positive effects on ecosystems. But what happens when certain species disappear from complex food webs? Can their function be taken over by other species? How many losses can ecosystems take? The iDiv Ecotron chambers carefully examine the food web in all its complexity. In addition, researchers can replace or entirely remove certain animal and plant species in the closed systems. “We can examine, for example, the interplay and the interactions among different species above and below the soil”, explains Prof. Nico Eisenhauer (iDiv and Leipzig University), who manages the facility. “Similar to a climate chamber, which simulates the warmer climate of the future, the iDiv Ecotron enables us to look at a future world which contains fewer species.”
Key issues of coexistence
In doing so, Eisenhauer and his colleagues wish to investigate three key issues:
Does the complexity of the interactions between the species affect the functions of an ecosystem? How dependent are ecosystem functions on the relationships between aboveground and belowground organisms and processes? What are the impacts of global change on biodiversity, interaction networks and ecosystem functions? These environmental issues are of far-reaching importance. The German Research Foundation (DFG) has, for that reason, funded the facility with roughly three million euros and is financing two employees. Also involved financially, the UFZ has modernised the hall of the iDiv Ecotron for three-quarters of a million euros and is financing one employee.
A unique high-tech facility
The goal of the experimental chambers is to explore ecosystem functions by manipulating complex animal and plant communities. The environmental conditions must be as constant as possible to avoid disruptive events, which could distort the results. The 24 chambers are therefore all structurally identical and deploy extensive technology, which sets and adjusts the light, temperature and precipitation. That means that, for the first time, it will be possible to manipulate aboveground and belowground communities and their interactions on relevant spatial scales. The “EcoUnits” are experimental chambers, which consist of a bottom section filled with soil, a top section, and a technical section, and stand 1.55 x 1.55 metres wide and 3.20 metres high. Each “EcoUnit” can be divided into up to four largely independent compartments, due to aboveground partition walls and underground steel cylinders (lysimeters). All chambers are equipped with extensive technology. This includes, for example, cameras that observe the interactions between animals and plants. “Because such a facility has not yet been built, we have invested a lot of time over the past years in developing and optimising the technology together with the manufacturers. In some areas, we had to enter uncharted territory, which has often not been easy. We’re so much happier that everything is now running and the scientific experiments can finally start”, reported Dr. Manfred Türke from the iDiv and Leipzig University, who is coordinating the work at the facility. After the pilot phase, the facility will also be made available to external scientists. A commission will decide on proposals and applications and allocate the capacities – as is customary for large-scale scientific research equipment of international importance.
Bad Lauchstädt as an internationally renowned research station
The iDiv Ecotron enriches the field research station of the UFZ in Bad Lauchstädt, which is gaining in national and international stature as an ecological research station due to the cooperation between the UFZ and iDiv. In addition to a multitude of experiments in soil and biodiversity research at this location, since 2013 the UFZ has operated a globally unique outdoor experiment known as the Global Change Experimental Facility (GCEF), in which a seven-hectare test area is used to examine the impact of climate change on different forms of land use. “The research station in Bad Lauchstädt, with a total area of about 40 hectares, has in recent years already made a name for itself among ecologists, thanks to the highly varied range of experiments. The station is now getting a further boost thanks to its collaboration with iDiv. “And actually, many experiments have only just started”, says a delighted Prof. François Buscot, who as head of the UFZ department of soil ecology is jointly responsible for the research station of the UFZ in Bad Lauchstädt, and is also Deputy Director of iDiv. Three platforms are among the new experiments: the MyDiv tree diversity experiment, the NutNet global research initiative to examine changes in nutrient availability and Drought-Net, the global network to examine the effects of extreme drought. With immediate effect, the iDiv Ecotron will complement these field experiments in Bad Lauchstädt and enrich biodiversity research in central Germany.
Volker Hahn / Tilo Arnhold
The iDiv Ecotron
Biodiversity-ecosystem functioning research under controlled environmental conditions
UFZ Experimental research station Bad Lauchstädt
Dr Manfred Türke
Scientific Coordinator iDiv Ecotron / German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig & Leipzig University
Prof Dr Nico Eisenhauer
Scientific head iDiv Ecotron & Head of Research Group Experimental Interaction Ecology / German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig & Leipzig University
Prof Dr François Buscot
Head of the Department of Soil Ecology / Helmholtz Centre for Environmental Research – UFZ & Co-Director German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig
as well as
Tilo Arnhold, Dr Volker Hahn
iDiv Media and Communications
Tel.: +49 341 9733 -109, -154
UFZ Press and Public Relations
Tel.: +49 341 235-1630
iDiv is a central facility of Leipzig University within the meaning of Section 92 (1) of the Act on Academic Freedom in Higher Education in Saxony (Sächsisches Hochschulfreiheitsgesetz, SächsHSFG). It is run together with the Martin Luther University Halle-Wittenberg and the Friedrich Schiller University Jena, as well as in cooperation with the Helmholtz Centre for Environmental Research – UFZ.
The following non-university research institutions are involved as cooperation partners: the Helmholtz Centre for Environmental Research – UFZ, the Max Planck Institute for Biogeochemistry (MPI BGC), the Max Planck Institute for Chemical Ecology (MPI CE), the Max Planck Institute for Evolutionary Anthropology (MPI EVA), the Leibniz Institute DSMZ–German Collection of Microorganisms and Cell Cultures, the Leibniz Institute of Plant Biochemistry (IPB), the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) and the Leibniz Institute Senckenberg Museum of Natural History Görlitz (SMNG).
In the Helmholtz Centre for Environmental Research (UFZ), scientists conduct research into the causes and consequences of far-reaching environmental changes. Their areas of study cover water resources, biodiversity, the consequences of climate change and possible adaptation strategies, environmental technologies and biotechnologies, bioenergy, the effects of chemicals in the environment and the way they influence health, modelling and social-scientific issues. Its guiding principle: Our research contributes to the sustainable use of natural resources and helps to provide long-term protection for these vital assets in the face of global change. The UFZ employs more than 1,100 staff at its sites in Leipzig, Halle and Magdeburg. It is funded by the federal government, Saxony and Saxony-Anhalt.
Tilo Arnhold | idw - Informationsdienst Wissenschaft
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Life Sciences
16.07.2018 | Earth Sciences
16.07.2018 | Physics and Astronomy | <urn:uuid:4930fbc4-f01a-499c-a6be-a7f0278acd67> | 3.28125 | 2,978 | Knowledge Article | Science & Tech. | 29.940267 | 95,593,152 |
the University of Oregon Physics Department
Here students will have an opportunity to measure redshifts for several galaxies using a set of common spectral lines here. While the spectra that students will be using have many lines (emission and absorption) students must concentrate on using the following sets: calcium H and K and hydrogen emission lines . Students are asked to determine if there is a correlation between the presence of emission lines in the spectra and the overall appearance (morphology) of the galaxy.
%0 Electronic Source %A University of Oregon Physics Department, %T The Hubble Law %V 2018 %N 18 July 2018 %9 application/java %U http://zebu.uoregon.edu/nsf/hub.html
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Information Storage In Bacteria DNA Update
Four months ago, Technovelgy readers found out about how researchers had encoded information into the DNA of bacteria (see Bacteria Save Your Data, Make Multiple Backups). The mainstream media finally caught up to this story, and delivered a great anecdote that I just had to share.
As you recall, a technique that allowed researchers to attach up to 100 bits of data to each organism was created at Keio University. They successfully encoded and attached the phrase "e=mc2 1905" to the DNA of bacillus subtilis, a common soil bacteria.
(Professor Masaru Tomita headed the research team)
Others had thought about this possibility before, as it turns out:
"In so doing they have accomplished at least a part of the dream that Jaron Lanier, a computer scientist and musician, and David Sulzer, a biologist at Columbia, enunciated in 1999. To create the ultimate time capsule as part of the millennium festivities at this newspaper, they proposed to encode a year’s worth of the New York Times magazine into the junk DNA of a cockroach. “The archival cockroach will be a robust repository,” Mr. Lanier wrote, “able to survive almost all conceivable scenarios.”
Truly an idea worthy of science fiction writers (and readers). It's such a good idea, I'm wondering if anyone has checked cockroach DNA for messages?
Via NY Times; see also the earlier article Bacteria Save Your Data, Make Multiple Backups for more details.
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P. Y. Le Traon
Full Text Available The launch of the French/US mission Topex/Poseidon (T/P (CNES/NASA in August 1992 was the start of a revolution in oceanography. For the first time, a very precise altimeter system optimized for large-scale sea level and ocean circulation observations was flying. T/P alone could not observe the mesoscale circulation. In the 1990s, the ESA satellites ERS-1/2 were flying simultaneously with T/P. Together with my CLS colleagues, we demonstrated that we could use T/P as a reference mission for ERS-1/2 and bring the ERS-1/2 data to an accuracy level comparable to T/P. Near-real-time high-resolution global sea level anomaly maps were then derived. These maps have been operationally produced as part of the SSALTO/DUACS system for the last 15 yr. They are now widely used by the oceanographic community and have contributed to a much better understanding and recognition of the role and importance of mesoscale dynamics. Altimetry needs to be complemented with global in situ observations. At the end of the 90s, a major international initiative was launched to develop Argo, the global array of profiling floats. This has been an outstanding success. Argo floats now provide the most important in situ observations to monitor and understand the role of the ocean on the earth climate and for operational oceanography. This is a second revolution in oceanography. The unique capability of satellite altimetry to observe the global ocean in near-real-time at high resolution and the development of Argo were essential for the development of global operational oceanography, the third revolution in oceanography. The Global Ocean Data Assimilation Experiment (GODAE was instrumental in the development of the required capabilities. This paper provides an historical perspective on the development of these three revolutions in oceanography which are very much interlinked. This is not an exhaustive review and I will mainly focus on the contributions we made together with many
Wisniewski, Rafal; Bak, Thomas
The Satellite Laboratory at the Department of Control Engineering of Aalborg University (SatLab) is a dynamic motion facility designed for analysis and test of micro spacecraft. A unique feature of the laboratory is that it provides a completely gravity-free environment. A test spacecraft......-axis magnetometer, three piezoelectric gyros, and four reaction wheels in a tetrahedron configuration. The operation of the spacecraft is fully autonomous. The data flow between the transducers and the onboard computer placed physically outside the satellite is provided by a radio link. The purpose...... can be implemented in the laboratory, e.g. three-axis attitude control, slew manoeuvres, spins stabilization using magnetic actuation and/or reaction wheels. The spacecraft attitude can be determined applying magnetometer measurements....
Wisniewski, Rafal; Bak, Thomas
The Satellite Laboratory at the Department of Control Engineering of Aalborg University (SatLab) is a dynamic motion facility designed for analysis and test of micro spacecraft. A unique feature of the laboratory is that it provides a completely gravity-free environment. A test spacecraft...... of the laboratory is to conduct dynamic tests of the control and attitude determination algorithms during nominal operation and in abnormal conditions. Further it is intended to use SatLab for validation of various algorithms for fault detection, accommodation and supervisory control. Different mission objectives...... can be implemented in the laboratory, e.g. three-axis attitude control, slew manoeuvres, spins stabilization using magnetic actuation and/or reaction wheels. The spacecraft attitude can be determined applying magnetometer measurements...
Lutey, Mark K.; Imler, Thomas A.; Davis, Robert J.
The Phillips Laboratory Space Experiments Directorate in conjunction with the Air Force Space Test Program (AF STP), Defense Advanced Research and Projects Agency (DARPA) and Strategic Defense Initiative Organization (SDIO), are managing five small satellite program initiatives: Lightweight Exo-Atmospheric Projectile (LEAP) sponsored by SDIO, Miniature Sensor Technology Integration (MSTI) sponsored by SDIO, Technology for Autonomous Operational Survivability (TAOS) sponsored by Phillips Laboratory, TechSat sponsored by SDIO, and the Advanced Technology Standard Satellite Bus (ATSSB) sponsored by DARPA. Each of these spacecraft fulfills a unique set of program requirements. These program requirements range from a short-lived `one-of-a-kind' mission to the robust multi- mission role. Because of these diverging requirements, each program is driven to use a different design philosophy. But regardless of their design, there is the underlying fact that small satellites do not always equate to small missions. These spacecraft with their use of or ability to insert new technologies provide more capabilities and services for their respective payloads which allows the expansion of their mission role. These varying program efforts culminate in an ATSSB spacecraft bus approach that will support moderate size payloads, up to 500 pounds, in a large set of orbits while satisfying the `cheaper, faster, better' method of doing business. This technical paper provides an overview of each of the five spacecraft, focusing on the objectives, payoffs, technologies demonstrated, and program status.
Chemical Oceanography presents a comprehensive examination of the chemistry of oceans through discussions of such topics as descriptive physical oceanography, the composition of seawater and the major...
National Oceanic and Atmospheric Administration, Department of Commerce — The Marine Geological Samples Laboratory (MGSL) of the Graduate School of Oceanography (GSO), University of Rhode Island is a partner in the Index to Marine and...
Guerra, André G. C.; Ferreira, António Sérgio; Costa, Maria; Nodar-López, Diego; Aguado Agelet, Fernando
Small satellites and autonomous vehicles have greatly evolved in the last few decades. Hundreds of small satellites have been launched with increasing functionalities, in the last few years. Likewise, numerous autonomous vehicles have been built, with decreasing costs and form-factor payloads. Here we focus on combining these two multifaceted assets in an incremental way, with an ultimate goal of alleviating the logistical expenses in remote oceanographic operations. The first goal is to create a highly reliable and constantly available communication link for a network of autonomous vehicles, taking advantage of the small satellite lower cost, with respect to conventional spacecraft, and its higher flexibility. We have developed a test platform as a proving ground for this network, by integrating a satellite software defined radio on an unmanned air vehicle, creating a system of systems, and several tests have been run successfully, over land. As soon as the satellite is fully operational, we will start to move towards a cooperative network of autonomous vehicles and small satellites, with application in maritime operations, both in-situ and remote sensing.
Deiotte, R.; Guyote, M.; Kelecy, T.; Hall, D.; Africano, J.; Kervin, P.
The MSSS satellite categorization laboratory is a fusion of robotics and digital imaging processes that aims to decompose satellite photometric characteristics and behavior in a controlled setting. By combining a robot, light source and camera to acquire non-resolved images of a model satellite, detailed photometric analyses can be performed to extract relevant information about shape features, elemental makeup, and ultimately attitude and function. Using the laboratory setting a detailed analysis can be done on any type of material or design and the results cataloged in a database that will facilitate object identification by "curve-fitting" individual elements in the basis set to observational data that might otherwise be unidentifiable. Currently the laboratory has created, an ST-Robotics five degree of freedom robotic arm, collimated light source and non-focused Apogee camera have all been integrated into a MATLAB based software package that facilitates automatic data acquisition and analysis. Efforts to date have been aimed at construction of the lab as well as validation and verification of simple geometric objects. Simple tests on spheres, cubes and simple satellites show promising results that could lead to a much better understanding of non-resolvable space object characteristics. This paper presents a description of the laboratory configuration and validation test results with emphasis on the non-resolved photometric characteristics for a variety of object shapes, spin dynamics and orientations. The future vision, utility and benefits of the laboratory to the SSA community as a whole are also discussed.
Murty, C.S.; Murty, V.S.N.
The chapter on physical oceanography of the Indian Ocean is written keeping in mind the graduate students and researchers. It starts with a brief introduction (citing latest expeditions) followed by the coastal and near processes (wave climate...
section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home ⺠Help ⺠Meteorology/Oceanography Help USNO Logo USNO Info Meteorology/Oceanography Help Send an e-mail regarding meteorology or oceanography products. Privacy Advisory Your E-Mail
Buijsman, M. C.; Church, I.; Haydel, J.; Martin, K. M.; Shiller, A. M.; Wallace, D. J.; Blancher, J.; Foltz, A.; Griffis, A. M.; Kosciuch, T. J.; Kincketootle, A.; Pierce, E.; Young, V. A.
To better prepare first-year Department of Marine Science MSc students of the University of Southern Mississippi for their science careers, we plan to execute a semester-long Physical Oceanography laboratory class that exposes the enrolled students to all aspects of interdisciplinary research: writing a proposal, planning a cruise, collecting and analyzing data, and presenting their results. Although some of these aspects may be taught in any such class, the incorporation of all these aspects makes this class unique.The fieldwork will be conducted by boat in the Rigolets in Louisiana, a 13-km long tidal strait up to 1 km wide connecting the Mississippi Sound with Lake Pontchartrain. The students have the opportunity to collect ADCP, CTD, multibeam sonar, sediment and water samples.A second novel characteristic of this class is that the instructor partnered with the Lake Pontchartrain Basin Foundation, a not for profit environmental advocacy group. The foundation will give an hour-long seminar on the natural history of the study area and its environmental problems. This information provides context for the students' research proposals and allows them to formulate research questions and hypotheses that connect their research objectives to societally relevant issues, such as coastal erosion, salt water intrusion, and water quality. The proposal writing and cruise planning is done in the first month of the 3.5-month long semester. In the second month two surveys are conducted. The remainder of the semester is spent on analysis and reporting. Whenever possible we teach Matlab for the students to use in their data analysis. In this presentation, we will report on the successes and difficulties associated with teaching such a multi-faceted class.
Wright, F. F.
Estuarine Oceanography is one in a series of single-topic problem modules intended for use in undergraduate and earth science courses. Designed for those interested in coastal oceanography or limnology, the module is structured as a laboratory supplement for undergraduate college classes but should be useful at all levels. The module has two…
Hollister, Charles D., Ed.
This booklet was prepared by practicing oceanographers to help college students in their search for professional direction. The booklet: (1) points out some frontiers of current research; (2) describes five major subfields of oceanography (marine geology and geophysics, oceanographic engineering, physical oceanography, chemical oceanography, and…
Pan, X.; Wong, G. T.; Tai, J.; Ho, T.
By using the observations from multiple satellite sensors, the climatology of the oceanography, including the surface wind vector, sea surface temperature (SST), surface chlorophyll a concentration (Chl_a), and vertically integrated net primary production (PPeu), in the northern South China Sea Shelf-sea (NoSoCS) and adjacent waters is evaluated. Regional and sub-regional mechanisms in driving the coastal processes, which influence the spatial and temporal distributional patterns in water component, are assessed. Seasonal vertical convective mixing by wind and surface heating/cooling is the primary force in driving the annual changes in SST and Chl_a in the open South China Sea (SCS), in which highly negative correlation coefficients between Chl_a and SST and moderately positive correlation coefficients between Chl_a and wind speed are found. Together, the seasonal variations in SST and wind speed account for about 80% of the seasonal variation in Chl_a. In the NoSoCS as a whole, however, the contribution is reduced to about 40%, primarily due to the effect of the Pearl River plume. A tongue of water extending eastward from the mouth of the River into the middle shelf with positive correlation coefficients between Chl_a and SST and around zero or slightly negative correlation coefficients between Chl_a and wind is the most striking feature in the NoSoCS. The westward and eastward propagations of the Pearl River plume are both very small during the northeast monsoonal season, driven primarily by the Coriolis effect. The abrupt increase in the areal coverage of the River plume, which is much more pronounced in the eastward propagation, between June and August can be attributed to the prevailing southwest monsoon as well as the annual peak of the river flow. Coastal upwelling is another sub-regional phenomenon in the NoSoCS. The upwelling at the shelf edge off the Taiwan Bank may be characterized by its elevated Chl_a. Its areal coverage and average Chl_a do not vary
Fisheries oceanography can be applied to fisheries ecology, fisheries management and practical fishing. Physico-chemical parameters of the environment (temperature, currents, waves, light, oxygen and salinity) have profound effect on fish...
National Oceanic and Atmospheric Administration, Department of Commerce — The Oceanography group maintains and provides Conductivity/Temperature/Depth (CTD) instruments to all Center cruises for measuring water column profiles of...
Aggarwal, Suresh K.
Mass spectrometry plays an important role in oceanography for various applications. Different types of inorganic as well as organic mass spectrometric techniques are being exploited world-wide to understand the different aspects of marine science, for palaeogeography, palaeoclimatology and palaeoecology, for isotopic composition and concentrations of different elements as well as for speciation studies. The present paper reviews some of the applications of atomic mass spectrometric techniques in the area of oceanography
Dalton, J. B.; Jamieson, C. S.; Shirley, J. H.; Pitman, K. M.; Kariya, M.; Crandall, P.
The bulk of our knowledge of icy satellite composition continues to be derived from ultraviolet, visible and infrared remote sensing observations. Interpretation of remote sensing observations relies on availability of laboratory reference spectra of candidate surface materials. These are compared directly to observations, or incorporated into models to generate synthetic spectra representing mixtures of the candidate materials. Spectral measurements for the study of icy satellites must be taken under appropriate conditions (cf. Dalton, 2010; also http://mos.seti.org/icyworldspectra.html for a database of compounds) of temperature (typically 50 to 150 K), pressure (from 10-9 to 10-3 Torr), viewing geometry, (i.e., reflectance), and optical depth (must manifest near infrared bands but avoid saturation in the mid-infrared fundamentals). The Planetary Ice Characterization Laboratory (PICL) is being developed at JPL to provide robust reference spectra for icy satellite surface materials. These include sulfate hydrates, hydrated and hydroxylated minerals, and both organic and inorganic volatile ices. Spectral measurements are performed using an Analytical Spectral Devices FR3 portable grating spectrometer from .35 to 2.5 microns, and a Thermo-Nicolet 6500 Fourier-Transform InfraRed (FTIR) spectrometer from 1.25 to 20 microns. These are interfaced with the Basic Extraterrestrial Environment Simulation Testbed (BEEST), a vacuum chamber capable of pressures below 10-9 Torr with a closed loop liquid helium cryostat with custom heating element capable of temperatures from 30-800 Kelvins. To generate optical constants (real and imaginary index of refraction) for use in nonlinear mixing models (i.e., Hapke, 1981 and Shkuratov, 1999), samples are ground and sieved to six different size fractions or deposited at varying rates to provide a range of grain sizes for optical constants calculations based on subtractive Kramers-Kronig combined with Hapke forward modeling (Dalton and
This volume is an outcome of the presentation of selected 74 papers at the International Symposium on the Oceanography of the Indian Ocean held at National Institute of Oceanography during January 1991. The unique physical setting of the northern...
Bruner de Miranda, Luiz; Kjerfve, Björn; Castro Filho, Belmiro Mendes de
This book provides an introduction to the complex system functions, variability and human interference in ecosystem between the continent and the ocean. It focuses on circulation, transport and mixing of estuarine and coastal water masses, which is ultimately related to an understanding of the hydrographic and hydrodynamic characteristics (salinity, temperature, density and circulation), mixing processes (advection and diffusion), transport timescales such as the residence time and the exposure time. In the area of physical oceanography, experiments using these water bodies as a natural laboratory and interpreting their circulation and mixing processes using theoretical and semi-theoretical knowledge are of fundamental importance. Small-scale physical models may also be used together with analytical and numerical models. The book highlights the fact that research and theory are interactive, and the results provide the fundamentals for the development of the estuarine research.
Basic concepts in oceanography include major wind patterns that drive ocean currents, and the effects that the earth's rotation, positions of land masses, and temperature and salinity have on oceanic circulation and hence global distribution of radioactivity. Special attention is given to coastal and near-coastal processes such as upwelling, tidal effects, and small-scale processes, as radionuclide distributions are currently most associated with coastal regions. (author)
Symposium on radiation transfer problems and satellite measurements in meteorology and oceanography. Symposium ueber Strahlungstransportprobleme und Satellitenmessungen in der Meteorologie und der Ozeanographie. Vortraege
The atmospherical cloud fields in the mesoscale and the synoptic scale are studied and classified with respect to brightness, form, structure, horizontal and vertical dimension, and surface temperature on the basis of satellite observations. The different developing stages and the drift of the clouds are analysed by satellite measurements; which give insight into the atmospheric processes, improving the possibilities for predictions. The wind velocities in the higher troposphere are of particular interest for civil aviation. The world climate program takes profit from the covering statistics of the cloud fields, and from measurements of the surface temperature, covering the continents and the sea. Such measurements can be performed by satellite-born radiometers, e.g. also with Meteosat. The surface radiation temperature distributions are the initial data for climate models aiming at climate predictions for the human society on a time scale of several years. Models describing the circulation in the atmosphere and in the sea as well as in the boundary region in between can be considered as a first step in this direction. Several reports are dedicated to the role of the radiation budget for the simulation and description of such physical processes. The changes of the radiation budget components in space and time as well as the resulting meteorological effects, in particular the number and the properties (first of all radiation temperature and albedo) of the clouds have an essential influence on the calculation of the radiation fluxes and divergencies in different layers of the atmosphere. Abstracts are available for 59 papers of this conference report.
Beauregard, J. L.
Capturing and retaining the interest of non-science majors in science classes can be difficult, no matter what type of science. At Berklee College of Music, this challenge is especially significant, as all students are music majors. In my Introductory Oceanography course, I use a final project as a way for the students to link class material with their own interests. The students may choose any format to present their projects to the class; however, many students write and perform original music. The performances of ocean-themed music have become a huge draw of the Introductory Oceanography course. In an effort to expand the reach of this music, several colleagues and I organized the first Earth Day event at Berklee, `Earthapalooza 2015.' This event included performances of music originally written for the final projects, as well as other musical performances, poetry readings, guest talks, and information booths. Although the idea of an Earth Day event is not new, this event is unique in that student performances really resonate with the student audience. Additionally, since many of these students will enter professional careers in the performance and recording industries, the potential exists for them to expose large audiences to the issues of oceanography through music. In this presentation, I will play examples of original student compositions and show video of the live student performances. I will also discuss the benefits and challenges of the final projects and the Earth Day event. Finally, I will highlight the future plans to continue ocean-themed music at Berklee.
section Advanced Search... Sections Home Time Earth Orientation Astronomy Meteorology Oceanography Ice You are here: Home ⺠FNMOC ⺠Meteorology Products FNMOC Logo FNMOC Navigation Meteorology Products Oceanography Products Tropical Applications Climatology and Archived Data Info Meteorology Products Global
Burns, J.A.; Matthews, M.S.
The present work is based on a conference: Natural Satellites, Colloquium 77 of the IAU, held at Cornell University from July 5 to 9, 1983. Attention is given to the background and origins of satellites, protosatellite swarms, the tectonics of icy satellites, the physical characteristics of satellite surfaces, and the interactions of planetary magnetospheres with icy satellite surfaces. Other topics include the surface composition of natural satellites, the cratering of planetary satellites, the moon, Io, and Europa. Consideration is also given to Ganymede and Callisto, the satellites of Saturn, small satellites, satellites of Uranus and Neptune, and the Pluto-Charon system
Liou, Jer-Chyi; Clark, S.; Fitz-Coy, N.; Huynh, T.; Opiela, J.; Polk, M.; Roebuck, B.; Rushing, R.; Sorge, M.; Werremeyer, M.
The goal of the DebriSat project is to characterize fragments generated by a hypervelocity collision involving a modern satellite in low Earth orbit (LEO). The DebriSat project will update and expand upon the information obtained in the 1992 Satellite Orbital Debris Characterization Impact Test (SOCIT), which characterized the breakup of a 1960 s US Navy Transit satellite. There are three phases to this project: the design and fabrication of DebriSat - an engineering model representing a modern, 60-cm/50-kg class LEO satellite; conduction of a laboratory-based hypervelocity impact to catastrophically break up the satellite; and characterization of the properties of breakup fragments down to 2 mm in size. The data obtained, including fragment size, area-to-mass ratio, density, shape, material composition, optical properties, and radar cross-section distributions, will be used to supplement the DoD s and NASA s satellite breakup models to better describe the breakup outcome of a modern satellite.
Liou, J.-C.; Fitz-Coy, N.; Werremeyer, M.; Huynh, T.; Voelker, M.; Opiela, J.
DebriSat is a planned laboratory ]based satellite hypervelocity impact experiment. The goal of the project is to characterize the orbital debris that would be generated by a hypervelocity collision involving a modern satellite in low Earth orbit (LEO). The DebriSat project will update and expand upon the information obtained in the 1992 Satellite Orbital Debris Characterization Impact Test (SOCIT), which characterized the breakup of a 1960 's US Navy Transit satellite. There are three phases to this project: the design and fabrication of an engineering model representing a modern, 50-cm/50-kg class LEO satellite known as DebriSat; conduction of a laboratory-based hypervelocity impact to catastrophically break up the satellite; and characterization of the properties of breakup fragments down to 2 mm in size. The data obtained, including fragment size, area ]to ]mass ratio, density, shape, material composition, optical properties, and radar cross ]section distributions, will be used to supplement the DoD fs and NASA fs satellite breakup models to better describe the breakup outcome of a modern satellite. Updated breakup models will improve mission planning, environmental models, and event response. The DebriSat project is sponsored by the Air Force fs Space and Missile Systems Center and the NASA Orbital Debris Program Office. The design and fabrication of DebriSat is led by University of Florida with subject matter experts f support from The Aerospace Corporation. The major milestones of the project include the complete fabrication of DebriSat by September 2013, the hypervelocity impact of DebriSat at the Air Force fs Arnold Engineering Development Complex in early 2014, and fragment characterization and data analyses in late 2014.
Guarner, Jeannette; Street, Cassandra; Matlock, Margaret; Cole, Lisa; Brierre, Francoise
Consolidation of laboratories has left many hospitals and satellite laboratories with minimal microbiologic testing. In many hospitals and satellite laboratories, Gram stains on primary specimens are still performed despite difficultly in maintaining proficiency. To maintain Gram stain proficiency at a community 450-bed hospital with an active emergency room we designed bimonthly challenges that require reporting Gram staining and morphology of different organisms. The challenges consist of five specimens prepared by the reference microbiology laboratory from cultures and primary specimens. Twenty to 23 medical laboratory scientists participate reading the challenges. Results from the challenges are discussed with each medical laboratory scientists. In addition, printed images from the challenges are presented at huddle to add microbiology knowledge. On the first three challenges, Gram staining was read correctly in 71%-77% of the time while morphology 53%-66%. In the last six challenges correct answers for Gram stain were 77%-99% while morphology 73%-96%. We observed statistically significant improvement when reading Gram stains by providing frequent challenges to medical laboratory scientists. The clinical importance of Gram stain results is emphasized during huddle presentations increasing knowledge and motivation to perform the test for patients.
Arbic, B. K.; Ansong, J. K.; Johnson, W.; Nyadjro, E. S.; Nyarko, E.
Because oceanography is a global science, it clearly benefits from the existence of a world-wide network of oceanographers. As with most STEM disciplines, sub-Saharan Africa is not as well represented in the field of oceanography as it should be, given its large population. The need for oceanographers in sub-Saharan Africa is great, due to a long list of ocean-related issues affecting African development, including but not limited to fishing, oil drilling, sea level rise, coastal erosion, shipping, and piracy. We view this as an opportunity as well as a challenge. Many of the world's fastest growing economies are in sub-Saharan Africa, and STEM capacity building could further fuel this growth. With support from the US National Science Foundation, we ran an oceanography summer school from August 24-27, 2015, at the Regional Maritime University (RMU) in Ghana, West Africa. This first summer school was lecture-based, with a focus on basic chemical oceanography, basic physical oceanography, ocean modeling, and satellite oceanography. About 35 participants came to almost every lecture, and about 20 other participants came to some of the lectures as their time permitted. The participants included RMU faculty, 12 students from the Kwame Nkrumah University of Science and Technology, one Associate Oceanographer from the University of Ghana, and some participants from private sector companies and Ghanaian governmental agencies. There were long and lively discussions at the end of each lecture, and there was a lengthy discussion at the conclusion of the school on how to improve future summer schools. In 2016 and 2017, we plan to divide into smaller groups so that participants can pursue their particular interests in greater depth, and to allow time for student presentations. We also plan to begin exploring the potential for research partnerships, and to utilize distance learning to involve more faculty and students from locations throughout Ghana and perhaps from even other
Gerber, Lisa M.; Lozier, M. Susan
MPOWIR Pattullo Conference; Charleston, South Carolina, 23-26 May 2010; Initiated in 2004, Mentoring Physical Oceanography Women to Increase Retention (MPOWIR) is a community-initiated and community-led program aimed at providing mentoring to junior women in physical oceanography to improve their retention in the field. The centerpiece of the MPOWIR program is the Pattullo Conference, a two-and-a-half-day mentoring event held biannually. The second conference was held in South Carolina. The conference is named for June Pattullo, the first woman to receive a Ph.D. in physical oceanography. The goals of the Pattullo Conference are to build community networks among junior and senior scientists, to provide junior scientists with feedback on their current and planned research projects, to provide advice to junior scientists on their career goals, to introduce both senior and junior scientists to aspects of professional development, and to raise awareness of issues confronting junior women among the senior scientist community.
Loder, Theodore C.; Glibert, Patricia M.
Chemical oceanography or marine chemistry are taught in many colleges and universities. This publication provides sources for instructors of such courses. The first section of this report is a detailed composite outline of a course in chemical oceanography. It includes fundamental topics taught in many chemical oceanography classes. The outline…
Teachers are always on the lookout for material to give their brightest students, in order to keep them occupied, stimulated and challenged, while the teacher gets on with helping the rest. They are also looking for material that can inspire and enthuse those who think that school is 'just boring!' Oceanography, well presented, has the capacity to do both. As a relatively young science, oceanography is not a core curriculum subject (possibly an advantage), but it draws on the traditional sciences of biology, chemistry, physic and geology, and can provide wonderful examples for teaching concepts in school sciences. It can also give good reasons for learning science, maths and technology. Exciting expeditions (research cruises) to far-flung places; opportunities to explore new worlds, a different angle on topical debates such as climate change, pollution, or conservation can bring a new life to old subjects. Access to 'real' data from satellites or Argo floats can be used to develop analytical and problem solving skills. The challenge is to make all this available in a form that can easily be used by teachers and students to enhance the learning experience. We learn by doing. Active teaching methods require students to develop their own concepts of what they are learning. This stimulates new neural connections in the brain - the physical manifestation of learning. There is a large body of evidence to show that active learning is much better remembered and understood. Active learning develops thinking skills through analysis, problem solving, and evaluation. It helps learners to use their knowledge in realistic and useful ways, and see its importance and relevance. Most importantly, properly used, active learning is fun. This paper presents experiences from a number of education outreach projects that have involved the National Oceanography Centre in Southampton, UK. All contain some element of active learning - from quizzes and puzzles to analysis of real data from
remote sensing from satellites. Sensing of oceanographic variables from aircraft began with the photographing of waves and ice. Since then remote measurement of sea surface temperatures and wave heights have become routine. Sensors tested for oceanographic applications include multi-band color cameras, radar scatterometers, infrared spectrometers and scanners, passive microwave radiometers, and radar imagers. Remote sensing has found its greatest application in providing rapid coverage of large oceanographic areas for synoptic and analysis and
Poteau, A.; Claustre, H.; Scheurle, C.; Jessin, T.; Fontana, C.
One objective of the "Ocean Autonomous Observation" team of the Laboratory of Oceanography of Villefranche-sur-mer is to develop new means to outreach our science activities to various audiences. Besides the scientific community, this includes students and targets the general public, school pupils, and stakeholders. In this context, we have acquired a digital video globe with tactile capabilities and we will present here the various applications that we have been developing. A first type of products concerns the visualization of oceanic properties (SST, salinity, density, Chla, O2, NO3, irradiance) by diving from the surface (generally from satellite data) into the Ocean interior (through the use of global data bases, Argo, WOA). In second place, specific applications deal with surface animations allowing highlighting the seasonality of some properties (Chla, SST, ice cover, currents; based on satellite as well as modeling outputs). Finally, we show a variety of applications developed using the tactile functionality of the spherical display. In particular real-time vertical profiles acquired by Bio-Argo floats become directly accessible for the entire open ocean. Such a new tool plus its novel applications has been presented to school children, and to the wider public (at the so-called "fête de la science") as well as to potential sponsors of our science-outreach activities. Their feedback has always been highly positive and encouraging in terms of impact. From the scientists point of view, the use of this new support can easily compete with the classical PowerPoint, is much more attractive and fun and undeniably helps to outreach the various aspects of our pluridisciplinary science.
Science review of the Beaufort Institute of Oceanography, the Halifax Fisheries Research Laboratory, and the St. Andrews Biological Station, 1990-91. Revue des sciences de l'Institut oceanographique de Bedford, du Laboratoire de recherche halieutique de Halifax, et de la Station biologique de St. Andrews, 1990-91
Smith, T E; Cook, J [eds.
A review is presented of the research and survey programs being undertaken in 1990-91 at the Bedford Institute of Oceanography, the Halifax Fisheries Research Laboratory, and the St. Andrews Biological Station (all in Nova Scotia). The broad objectives of these programs are to perform applied research leading to the provision of advice on the management of marine and freshwater environments, including fisheries and offshore hydrocarbon resources; to perform targeted basic research in accordance with the mandates of Canada's Department of Fisheries and Oceans, Environment Canada, and Energy, Mines and Resources; to perform surveys and cartographic work; and to respond to major marine environmental emergencies. The research and survey work encompasses the fields of marine geology and geophysics, physical oceanography, marine chemistry, biological oceanography, fisheries research, seabird research, and navigational surveys and cartography. Topics of specific projects reviewed include marine pollution detection, phytoplankton profiling, seal populations, ocean mapping, geographic information systems, fish and invertebrate nutrition, shellfish culture, lobster habitat ecology, physics and biology of the Georges Bank frontal system, water-level instrumentation, data acquisition techniques, sea ice monitoring, salmon management, nearshore sedimentary processes, and oil/gas distribution in offshore basins. Separate abstracts have been prepared for three project reports from this review.
Nole, Gabriele; Scorza, Francesco; Lanorte, Antonio; Manzi, Teresa; Lasaponara, Rosa
This paper aims to present the development of a tool to integrate time series from active and passive satellite sensors (such as of MODIS, Vegetation, Landsat, ASTER, COSMO, Sentinel) into a virtual laboratory to support studies on landscape and archaeological landscape, investigation on environmental changes, estimation and monitoring of natural and anthropogenic risks. The virtual laboratory is composed by both data and open source tools specifically developed for the above mentioned applications. Results obtained for investigations carried out using the implemented tools for monitoring land degradation issues and subtle changes ongoing on forestry and natural areas are herein presented. In detail MODIS, SPOT Vegetation and Landsat time series were analyzed comparing results of different statistical analyses and the results integrated with ancillary data and evaluated with field survey. The comparison of the outputs we obtained for the Basilicata Region from satellite data analyses and independent data sets clearly pointed out the reliability for the diverse change analyses we performed, at the pixel level, using MODIS, SPOT Vegetation and Landsat TM data. Next steps are going to be implemented to further advance the current Virtual Laboratory tools, by extending current facilities adding new computational algorithms and applying to other geographic regions. Acknowledgement This research was performed within the framework of the project PO FESR Basilicata 2007/2013 - Progetto di cooperazione internazionale MITRA "Remote Sensing tecnologies for Natural and Cultural heritage Degradation Monitoring for Preservation and valorization" funded by Basilicata Region Reference 1. A. Lanorte, R Lasaponara, M Lovallo, L Telesca 2014 Fisher-Shannon information plane analysis of SPOT/VEGETATION Normalized Difference Vegetation Index (NDVI) time series to characterize vegetation recovery after fire disturbance International Journal of Applied Earth Observation and
Bruno, B. C.; Achilles, K.; Walker, G.; Weersing, K.; Team, A
The Center for Microbial Oceanography: Research and Education (C-MORE) is a multi-institution Science and Technology Center, established by the National Science Foundation in 2006. C-MORE's research mission is to facilitate a more comprehensive understanding of the diverse assemblages of microorganisms in the sea, ranging from the genetic basis of marine microbial biogeochemistry including the metabolic regulation and environmental controls of gene expression, to the processes that underpin the fluxes of carbon, related bioelements, and energy in the marine environment. The C-MORE education and outreach program is focused on increasing scientific literacy in microbial oceanography among students, educators, and the general public. A first step toward this goal is defining the key concepts that constitute microbial oceanography. After lengthy discussions with scientists and educators, both within and outside C-MORE, we have arrived at six key concepts: 1) Marine microbes are very small and have been around for a long time; 2) Life on Earth could not exist without microbes; 3) Most marine microbes are beneficial; 4) Microbes are everywhere: they are extremely abundant and diverse; 5) Microbes significantly impact our global climate; and 6) There are new discoveries every day in the field of microbial oceanography. A C-MORE-produced brochure on these six key concepts will be distributed at the meeting. Advanced copies may be requested by email or downloaded from the C-MORE web site(http://cmore.soest.hawaii.edu/downloads/MO_key_concepts_hi-res.pdf). This brochure also includes information on career pathways in microbial oceanography, with the aim of broadening participation in the field. C-MORE is eager to work in partnership to incorporate these key concepts into other science literacy publications, particularly those involving ocean and climate literacy. We thank the following contributors and reviewers: P Chisholm, A Dolberry, and A Thompson (MIT); N Lawrence
K. M. Buddhiraju
Full Text Available In this paper a virtual laboratory for the Satellite Image Processing and Analysis (v-SIPAL being developed at the Indian Institute of Technology Bombay is described. v-SIPAL comprises a set of experiments that are normally carried out by students learning digital processing and analysis of satellite images using commercial software. Currently, the experiments that are available on the server include Image Viewer, Image Contrast Enhancement, Image Smoothing, Edge Enhancement, Principal Component Transform, Texture Analysis by Co-occurrence Matrix method, Image Indices, Color Coordinate Transforms, Fourier Analysis, Mathematical Morphology, Unsupervised Image Classification, Supervised Image Classification and Accuracy Assessment. The virtual laboratory includes a theory module for each option of every experiment, a description of the procedure to perform each experiment, the menu to choose and perform the experiment, a module on interpretation of results when performed with a given image and pre-specified options, bibliography, links to useful internet resources and user-feedback. The user can upload his/her own images for performing the experiments and can also reuse outputs of one experiment in another experiment where applicable. Some of the other experiments currently under development include georeferencing of images, data fusion, feature evaluation by divergence andJ-M distance, image compression, wavelet image analysis and change detection. Additions to the theory module include self-assessment quizzes, audio-video clips on selected concepts, and a discussion of elements of visual image interpretation. V-SIPAL is at the satge of internal evaluation within IIT Bombay and will soon be open to selected educational institutions in India for evaluation.
Indexed are articles relating to oceanography and limnology published in "The Science Teacher" between 1960 and 1969. Articles are indexed under title, author, and topic. Topics include background information, course descriptions, and laboratory equipment and techniques. (EB)
Antoine, David; Babin, Marcel; Berthon, Jean-François; Bricaud, Annick; Gentili, Bernard; Loisel, Hubert; Maritorena, Stéphane; Stramski, Dariusz
André Morel (1933-2012) was a prominent pioneer of modern optical oceanography, enabling significant advances in this field. Through his forward thinking and research over more than 40 years, he made key contributions that this field needed to grow and to reach its current status. This article first summarizes his career and then successively covers different aspects of optical oceanography where he made significant contributions, from fundamental work on optical properties of water and particles to global oceanographic applications using satellite ocean color observations. At the end, we share our views on André's legacy to our research field and scientific community.
Meteorology Oceanography Ice You are here: Home ⺠FNMOC FNMOC Logo FNMOC Navigation Meteorology Products Oceanography Products Tropical Applications Climatology and Archived Data Info The Fleet Numerical Meteorology and Oceanography Center (FNMOC) The Fleet Numerical Meteorology and Oceanography Center (FNMOC
Gu, M. F.; Beiersdorfer, P.; Brown, G. V.; Graf, A.; Kelley, R. I.; Kilbourne, C. A.; Porter, F. S.; Kahn, S. M,
We present laboratory spectra of dielectronic recombination (DR) satellite transitions attached to the He-like and H-like iron resonance lines obtained with the NASA Goddard Space Flight Center X-ray calorimeter and produced by a thermal plasma simu1ation technique on the EBIT-I electron beam ion trap at the Lawrence Livermore National Laboratory. We demonstrate that the calorimeter has sufficient spectral resolution in the 6-9 keV range to provide reliable measurements not only of standard DR satellite to resonance line intensities but also of DR satellite to DR satellite ratios that can be used to diagnose nonthermal electron distributions. Electron temperatures derived from the measured line intensities are consistent with the temperature of the simulated plasma. Temperature measurements based on DR satellite transitions have significant advantages over those based on collisional ionization equilibrium or continuum shape. Thus, successful demonstration of this method with the X-ray calorimeter is an important step fur its application in X-ray astronomy.
O. D. Shishkina
Full Text Available An interaction of internal solitary waves with the shelf edge in the time periods related to the presence of a pronounced seasonal pycnocline in the Red Sea and in the Alboran Sea is analysed via satellite photos and SAR images. Laboratory data on transformation of a solitary wave of depression while passing along the transverse bottom step were obtained in a tank with a two-layer stratified fluid. The certain difference between two characteristic types of hydrophysical phenomena was revealed both in the field observations and in experiments. The hydrological conditions for these two processes were named the "deep" and the "shallow" shelf respectively. The first one provides the generation of the secondary periodic short internal waves – "runaway" edge waves – due to change in the polarity of a part of a soliton approaching the shelf normally. Another one causes a periodic shear flow in the upper quasi-homogeneous water layer with the period of incident solitary wave. The strength of the revealed mechanisms depends on the thickness of the water layer between the pycnocline and the shelf bottom as well as on the amplitude of the incident solitary wave.
Tello, Olvido; Gómez, María; González, Sonsoles
Since 1914, the Spanish Institute of Oceanography (IEO) performs multidisciplinary studies of the marine environment. In same case are systematic studies and in others are specific studies for special requirements (El Hierro submarine volcanic episode, spill Prestige, others.). Different methodologies and data acquisition techniques are used depending on studies aims. The acquired data are stored and presented in different formats. The information is organized into different databases according to the subject and the variables represented (geology, fisheries, aquaculture, pollution, habitats, etc.). Related to physical and chemical oceanography data, in 1964 was created the DATA CENTER of IEO (CEDO), in order to organize the data about physical and chemical variables, to standardize this information and to serve the international data network SeaDataNet. www.seadatanet.org. This database integrates data about temperature, salinity, nutrients, and tidal data. CEDO allows consult and download the data. http://indamar.ieo.es On the other hand, related to data about marine species in 1999 was developed SIRENO DATABASE. All data about species collected in oceanographic surveys carried out by researches of IEO, and data from observers on fishing vessels are incorporated in SIRENO database. In this database is stored catch data, biomass, abundance, etc. This system is based on architecture ORACLE. Due to the large amount of information collected over the 100 years of IEO history, there is a clear need to organize, standardize, integrate and relate the different databases and information, and to provide interoperability and access to the information. Consequently, in 2000 it emerged the first initiative to organize the IEO spatial information in an Oceanography Information System, based on a Geographical Information System (GIS). The GIS was consolidated as IEO institutional GIS and was created the Spatial Data Infrastructure of IEO (IDEO) following trend of INSPIRE. All
Emerson, Steven; Hedges, John
The principles of chemical oceanography provide insight into the processes regulating the marine carbon cycle. The text offers a background in chemical oceanography and a description of how chemical elements in seawater and ocean sediments are used as tracers of physical, biological, chemical and geological processes in the ocean. The first seven chapters present basic topics of thermodynamics, isotope systematics and carbonate chemistry, and explain the influence of life on ocean chemistry and how it has evolved in the recent (glacial-interglacial) past. This is followed by topics essential to understanding the carbon cycle, including organic geochemistry, air-sea gas exchange, diffusion and reaction kinetics, the marine and atmosphere carbon cycle and diagenesis in marine sediments. Figures are available to download from www.cambridge.org/9780521833134. Ideal as a textbook for upper-level undergraduates and graduates in oceanography, environmental chemistry, geochemistry and earth science and a valuable reference for researchers in oceanography.
This paper highlights history of the oceanography of the Indian Ocean. Oceanographic activities during Ancient period, Medieval period, British period, Post-Independence period are briefly discussed. The role of the IIOE, IOC, UNESCO are also...
CSIR-National Institute of Oceanography being one of its kind in the country The article describes the on-going researches and projects in contributing to the science in the field of Marine science....
A consortium consisting of the NASA Orbital Debris Program Office, U.S. Air Force's Space and Missile Systems Center, the Aerospace Corporation, and University of Florida is planning a series of hypervelocity impact experiments on mockup targets at the U.S. Air Force's Arnold Engineering Development Complex (AEDC) in early 2014. The target for the first experiment resembles a rocket upper stage whereas the target for the second experiment represents a typical 60-cm/50-kg class payload that incorporates modern spacecraft materials and components as well as exterior wrap of multi-layer insulation and three solar panels. The projectile is designed with the maximum mass that AEDC's Range G two-stage light gas gun can accelerate to an impact speed of 7 km/sec. The impact energy is expected to be close to 15 MJ to ensure catastrophic destruction of the target after the impact. Low density foam panels are installed inside the target chamber to slow down and soft-catch the fragments for post-impact processing. Diagnostic instruments, such as x-ray and high speed optical cameras, will also be used to record the breakup process. The main goal of this "DebriSat" project is to characterize the physical properties, including size, mass, shape, and density distributions, of orbital debris that would be generated by a hypervelocity collision involving an upper stage or a modern satellite in the low Earth orbit environment. In addition, representative fragments will be selected for laboratory optical and radar measurements to allow for better interpretation of data obtained by telescope and radar observations. This paper will provide a preliminary report of the impact results and the plans to process, measure, and analyze the fragments.
Lightholder, Jack; Thoesen, Andrew; Adamson, Eric; Jakubowski, Jeremy; Nallapu, Ravi; Smallwood, Sarah; Raura, Laksh; Klesh, Andrew; Asphaug, Erik; Thangavelautham, Jekan
Exploration of asteroids, comets and small moons (small bodies) can answer fundamental questions relating to the formation of the solar system, the availability of resources, and the nature of impact hazards. Near-earth asteroids and the small moons of Mars are potential targets of human exploration. But as illustrated by recent missions, small body surface exploration remains challenging, expensive, and fraught with risk. Despite their small size, they are among the most extreme planetary environments, with low and irregular gravity, loosely bound regolith, extreme temperature variation, and the presence of electrically charged dust. Here we describe the Asteroid Origins Satellite (AOSAT-I), an on-orbit, 3U CubeSat centrifuge using a sandwich-sized bed of crushed meteorite fragments to replicate asteroid surface conditions. Demonstration of this CubeSat will provide a low-cost pathway to physical asteroid model validation, shed light on the origin and geophysics of asteroids, and constrain the design of future landers, rovers, resource extractors, and human missions. AOSAT-I will conduct scientific experiments within its payload chamber while operating in two distinct modes: (1) as a nonrotating microgravity laboratory to investigate primary accretion, and (2) as a rotating centrifuge producing artificial milligravity to simulate surface conditions on asteroids, comets and small moons. AOSAT-I takes advantage of low-cost, off-the-shelf components, modular design, and the rapid assembly and instrumentation of the CubeSat standard, to answer fundamental questions in planetary science and reduce cost and risk of future exploration.
Pantoja, Silvio; Luis Iriarte, José; Daneri, Giovanni
Chilean Patagonia is one of the most extended fjord regions in the world that covers nearly 240,000 km 2 with an extremely complex coastline and topography in one of the least densely populated areas of the country (1-8 inhabitants every 10 km 2). In recent years, the area has been undergoing somewhat intense pressure since several commercial projects in hydroelectricity, tourism, and commercial salmon and mytilid cultures have been developed, or are in progress. Concomitantly, several large research programs have been devised to study the physical, chemical, and biological environment of Patagonia, such as the CIMAR FIORDO, and recently COPAS Sur-Austral based at Universidad de Concepcion, that attempts to close the bridge between oceanographic knowledge and its use by society. In this introductory article we summarize the collection of papers comprising this Special Issue of Continental Shelf Research. These papers deal with aspects of regional oceanography and geology, inorganic and organic geochemistry, ecology of pelagic and benthic organisms, and past changes in productivity.
Cracknell, A P [ed.
Various aspects of remote sensing are discussed. Topics include: the EARTHNET data acquisition, processing, and distribution facility the design and implementation of a digital interactive image processing system geometrical aspects of remote sensing and space cartography remote sensing of a complex surface legal aspects of remote sensing remote sensing of pollution, dust storms, ice masses, and ocean waves and currents use of satellite images for weather forecasting. Notes on field trips and work-sheets for laboratory exercises are included.
Full Text Available Plankton ecology has been the object of intense research and progress in the last few decades. This has been partly due to technological advances that have facilitated the multidisciplinary and high-resolution sampling of ecosystems and improved experimentation and analytical methodologies, and to sophisticated modelling. In addition, exceptional researchers have had the vision to integrate all these innovative tools to form a solid theoretical background in ecology. Here we provide an overview of the outstanding research work conducted by Professor Marta Estrada and her pioneering contribution to different areas of research in the last four decades. Her research in biological oceanography has mainly focussed on phytoplankton ecology, taxonomy and physiology, the functional structure of plankton communities, and physical and biological interactions in marine ecosystems. She has combined a variety of field and laboratory approaches and methodologies, from microscopy to satellite observations, including in-depth statistical data analysis and modelling. She has been a reference for scientists all over the world. Here, her contributions to plankton ecology are summarized by some of her students and closest collaborators, who had the privilege to share their science and everyday experiences with her.
Li, W. K. W.
Macroecology is the study of ecological patterns discerned at a spatial, temporal, or organization scale higher than that at which the focal entities interact. Such patterns are statistical or emergent manifestations arising from the ensemble of component entities. Although macroecology is a neologism largely based in terrestrial and avian ecology, macroscopic patterns have long been recognised in biological oceanography. Familiar examples include Redfield elemental stoichiometry, Elton trophic pyramids, Sheldon biomass spectrum, and Margalef life-forms mandala. Macroecological regularities can often be found along various continua, such as along body size in power-law scaling or along habitat temperature in metabolic theory. Uniquely in oceanography, a partition of the world ocean continuum into Longhurst biogeochemical provinces provides a spatial organization well-suited for macroecological investigations. In this rational discrete approach, fundamental processes in physical and biological oceanography that differentiate a set of non-overlapping ocean regions also appear to shape the macroecological structure of phytoplankton communities.
Josep L. Pelegrí
Full Text Available The field of physical oceanography has undergone exponential growth in Spain during the last few decades. From a handful of self-taught researchers in the late 1960s there are now several hundred physical oceanographers distributed in some 20 Spanish institutions, and many more working overseas. The First Spanish Physical Oceanography Meeting (EOF1, held in Barcelona in October 2010, was a good example of the high quality and large variety of this research. The facilities and human resources are excellent but the alarming decrease in public investment in science due to the economic crisis must lead the Spanish physical oceanography community to define its current priorities. In this introductory paper to EOF1 we revise our history and where we are now, and suggest that progress in the near future will rely on our intelligence to sustain and enhance human capital, partnership and society-oriented research.
Loeffler, Mark J.; Hudson, Reggie L.
Laboratory experiments have demonstrated that magnetospheric radiation in the Jovian system drives reaction chemistry in ices at temperatures relevant to Europa and other icy satellites. Here we present new results on thermally-induced reactions at 50-100 K in solid H2O-SO2 mixtures, reactions that take place without the need for a high-radiation environment. We find that H2O and SO2 react to produce sulfur Oxyanions, such as bisulfite, that as much as 30% of the SO2 can be consumed through this reaction, and that the products remain in the ice when the temperature is lowered, indicating that these reactions are irreversible. Our results suggest that thermally-induced reactions can alter the chemistry at temperatures relevant to the icy satellites in the Jovian system.
Sandia has recently completed the flight certification test series for the Multi-Spectral Thermal Imaging satellite (MTI), which is a small satellite for which Sandia was the system integrator. A paper was presented at the 16th Aerospace Testing Seminar discussing plans for performing the structural dynamics certification program for that satellite. The testing philosophy was originally based on a combination of system level vibroacoustic tests and component level shock and vibration tests. However, the plans evolved to include computational analyses using both Finite Element Analysis and Statistical Energy Analysis techniques. This paper outlines the final certification process and discuss lessons learned including both things that went well and things that should/could have been done differently.
Ivancic, William D.; Brooks, David E.; Frantz, Brian D.
A digitized video application was used to help determine minimum quality of service parameters for asynchronous transfer mode (ATM) over satellite. For these tests, binomially distributed and other errors were digitally inserted in an intermediate frequency link via a satellite modem and a commercial gaussian noise generator. In this paper, the relation- ship between the ATM cell error and cell loss parameter specifications is discussed with regard to this application. In addition, the video-encoding algorithms, test configurations, and results are presented in detail.
Ivancic, William D.; Bobinsky, Eric A.
Results of 45-Mbps DS3 intermediate-frequency loopback measurements of asynchronous transfer mode (ATM) quality of service parameters (cell error ratio and cell loss ratio) are presented. These tests, which were conducted at the NASA Lewis Research Center in support of satellite-ATM interoperability research, represent initial efforts to quantify the minimum parameters for stringent ATM applications, such as MPEG-1 and MPEG-2 video transmission. Portions of these results were originally presented to the International Telecommunications Union's ITU-R Working Party 4B in February 1996 in support of their Draft Preliminary Recommendation on the Transmission of ATM Traffic via Satellite.
of Oceanography, La Jolla, CA; 5-10 June 2011 Attended: Algae + Fish = Ocean Mixing? Conference, La Jolla, CA; 5-6 July 2011 Attended: JASON Summer...the scientific work of Klaus Hasselmann at the Max Planck Institute for Meteorology; Hamburg , Germany; 09 November 2011 Keynote Address: Nansen
Madrazo, Gerry M., Jr., Ed.; Hounshell, Paul B., Ed.
This monograph attempts to show the importance of bringing marine biology into science classrooms, discusses what makes the ocean so important and explains why oceanography should be included in the science curriculum regardless of where students live. Section I, "Getting Started," includes discussions on the following: (1) "Why Marine Biology?";…
Observing Laboratory ( EOL ), but also contains an internal architecture which will allow it to evolve into a collaborative communication tool...an additional 50,988 "common" products were generated (241 plot types), along with 47,600 overlays (101 plot types). From 52 non- EOL sources...24,471 products were collected, and from 1486 EOL data collections, 643,263 "federated" products were indexed and made available through itop.org
Tel, E.; Balbin, R.; Cabanas, J. M.; Garcia, M. J.; Garcia-Martinez, M. C.; Gonzalez-Pola, C.; Lavin, A.; Lopez-Jurado, J. L.; Rodriguez, C.; Ruiz-Villarreal, M.; Sanchez-Leal, R. F.; Vargas-Yanez, M.; Velez-Belchi, P.
Since its foundation, 100 years ago, the Spanish Institute of Oceanography (IEO) has been observing and measuring the ocean characteristics. Here is a summary of the initiatives of the IEO in the field of the operational oceanography (OO). Some systems like the tide gauges network has been working for more than 70 years. The IEO standard sections began at different moments depending on the local projects, and nowadays there are more than 180 coastal stations and deep-sea ones that are systematically sampled, obtaining physical and biochemical measurements. At this moment, the IEO Observing System (IEOOS) includes 6 permanent moorings equipped with currentmeters, an open-sea ocean-meteorological buoy offshore Santander and an SST satellital image reception station. It also supports the Spanish contribution to the ARGO international program with 47 deployed profilers, and continuous monitoring thermosalinometers, meteorological stations and ADCP onboard the IEO research vessels. The system is completed with the IEO contribution to the RAIA and Gibraltar observatories, and the development of regional prediction models. All these systematic measurements allow the IEO to give responses to ocean research activities, official agencies requirements and industrial and main society demands as navigation, resource management, risks management, recreation, etc, as well as for management development pollution-related economic activities or marine ecosystems. All these networks are linked to international initiatives, framed largely in supranational programs Earth observation sponsored by the United Nations or the European Union. The synchronic observation system permits following spatio-temporal description of some events, as new deep water formation in the Mediterranean Sea and the injection of heat to intermediate waters in the Bay of Biscay after some colder northern storms in winter 2005.
StenniSphere at NASA's John C. Stennis Space Center in Hancock County, Miss., invites visitors to discover why America comes to Stennis Space Center before going into space. Designed to entertain while educating, StenniSphere includes informative displays and exhibits from NASA and other agencies located at Stennis, such as this one from the Naval Meteorology and Oceanography Command. Visitors can 'travel' three-dimensionally under the sea and check on the weather back home in the Weather Center.
Designed to entertain while educating, StenniSphere at the John C. Stennis Space Center in Hancock County, Miss., includes informative displays and exhibits from NASA and other agencies located at Stennis, such as this one from the Naval Meteorology and Oceanography Command. Visitors can 'travel' three-dimensionally under the sea and check on the weather back home in the Weather Center. StenniSphere is open free of charge from 9 a.m. to 5 p.m. daily.
Peral, Eva; Rodriguez, Ernesto; Fernandez, Daniel Esteban; Johnson, Michael P.; Blumstein, Denis
The proposed Surface Water and Ocean Topography (SWOT) mission would demonstrate a new measurement technique using radar interferometry to obtain wide-swath measurements of water elevation at high resolution over ocean and land, addressing the needs of both the hydrology and oceanography science communities. To accurately evaluate the performance of the proposed SWOT mission, we have developed several data product simulators at different levels of fidelity and complexity.
Chatterji, A.; Ingole, B.S.; Parulekar, A.H.
The note gives an account, for the first time in India, of an Aquaculture Laboratory with open type seawater circulating system developed at the National Institute of Oceanography, Goa, India. Besides describing the details of the system...
In connection with studies on the feasibility of the safe disposal of radioactive waste, from a large scale nuclear power programme, either on the bed of the deep ocean or within the deep ocean bed, preparation of the present document was commissioned by the (United Kingdom) Department of the Environment. It attempts (a) to summarize the present state of knowledge of the deep ocean environment relevant to the disposal options and assess the processes which could aid or hinder dispersal of material released from its container; (b) to identify areas of research in which more work is needed before the safety of disposal on, or beneath, the ocean bed can be assessed; and (c) to indicate which areas of research can or should be undertaken by British scientists. The programmes of international cooperation in this field are discussed. The report is divided into four chapters dealing respectively with geology and geophysics, geochemistry, physical oceanography and marine biology. (U.K.)
Dong, Mingmei; Xu, Shanshan; Miao, Qingsheng; Yue, Xinyang; Lu, Jiawei; Yang, Yang
Operational oceanography requires the quantity, quality, and availability of data set and the timeliness and effectiveness of data products. Without steady and strong operational system supporting, operational oceanography will never be proceeded far. In this paper we describe an integrated platform named Argo Workstation. It operates as a data processing and management system, capable of data collection, automatic data quality control, visualized data check, statistical data search and data service. After it is set up, Argo workstation provides global high quality Argo data to users every day timely and effectively. It has not only played a key role in operational oceanography but also set up an example for operational system.
National Oceanic and Atmospheric Administration, Department of Commerce — The Scripps Institution of Oceanography (SIO) compiled data on the geochemistry of marine ferromanganese nodules, funded by the U.S. National Science Foundation...
Varkey, M.J.; Murty, V.S.N.; Suryanarayana, A.
Physical oceanography of the Bay of Bengal and Andaman Sea is reviewed for the first time. All available information for over 50 years is consolidated in this review. To begin with, information on peripheral or related aspects of climate...
Federal Laboratory Consortium — The GPS satellite simulation facility consists of a GPS satellite simulator controlled by either a Silicon Graphics Origin 2000 or PC depending upon unit under test...
During the past few years, significant progress has occurred in the field of physical oceanography partly as a consequence of developing cooperation and international participation in well-coordinated ocean research programmes. Although these programs were not designed specifically to address CRESP problems, many have proved to be directly relevant to CRESP objectives. For example, MODE, POLYMODE, and Tourbillon were intensive site-specific experiments that included studies of dispersion processes throughout the water column. NOAMP and GME were also site specific, involved the entire water column, and even stressed near-bottom and suspended-sediment processes. Others, (e.g., WOCE) are larger in scope and include extensive observations of the general circulation of entire ocean basins. As a whole, they contribute immensely to improving the data base for exchange and transport processes and thereby for the verification and validation of both regional-scale and general-circulation ocean models. That, in turn, is directly relevant to radiological assessments. Selected papers deriving from experiments such as these are discussed and referenced below
Brice, D.; Foley, S.; Knox, R. A.; Mauricio, P.
Now in its fourth year, "In the Footsteps of Roger Revelle" (IFRR) is a middle school science education program that draws student interest, scientific content and coherence with National Science Standards from real-time research at sea in fields of physical science. As a successful collaboration involving Scripps Institution of Oceanography (SIO), Woods Hole Oceanographic Institution (WHOI), National Oceanic and Atmospheric Administration (NOAA), Office of Naval Research (ONR), National Science Foundation (NSF), San Diego County Office of Education (SDCOE), and San Marcos Middle School (SMMS), IFRR brings physical oceanography and related sciences to students at the San Marcos Middle School in real-time from research vessels at sea using SIO's HiSeasNet satellite communication system. With their science teacher on the ship as an education outreach specialist or ashore guiding students in their interactions with selected scientists at sea, students observe shipboard research being carried out live via videoconference, daily e-mails, interviews, digital whiteboard sessions, and web interaction. Students then research, design, develop, deploy, and field-test their own data-collecting physical oceanography instruments in their classroom. The online interactive curriculum encourages active inquiry with intellectually stimulating problem-solving, enabling students to gain critical insight and skill while investigating some of the most provocative questions of our time, and seeing scientists as role- models. Recent science test scores with IFRR students have shown significant increases in classes where this curriculum has been implemented as compared to other classes where the traditional curriculum has been used. IFRR has provided students in the San Diego area with a unique opportunity for learning about oceanographic research, which could inspire students to become oceanographers or at least scientifically literate citizens - a benefit for a country that depends
Elosegui, P.; Wilkinson, J.; Olsson, M.; Rodwell, S.; James, A.; Hagan, B.; Hwang, B.; Forsberg, R.; Gerdes, R.; Johannessen, J.; Wadhams, P.; Nettles, M.; Padman, L.
Project "Arctic Ocean sea ice and ocean circulation using satellite methods" (SATICE), is the first high-rate, high-precision, continuous GPS positioning experiment on sea ice in the Arctic Ocean. The SATICE systems collect continuous, dual-frequency carrier-phase GPS data while drifting on sea ice. Additional geophysical measurements also collected include ocean water pressure, ocean surface salinity, atmospheric pressure, snow-depth, air-ice-ocean temperature profiles, photographic imagery, and others, enabling sea ice drift, freeboard, weather, ice mass balance, and sea-level height determination. Relatively large volumes of data from each buoy are streamed over a satellite link to a central computer on the Internet in near real time, where they are processed to estimate the time-varying buoy positions. SATICE system obtains continuous GPS data at sub-minute intervals with a positioning precision of a few centimetres in all three dimensions. Although monitoring of sea ice motions goes back to the early days of satellite observations, these autonomous platforms bring out a level of spatio-temporal detail that has never been seen before, especially in the vertical axis. These high-resolution data allows us to address new polar science questions and challenge our present understanding of both sea ice dynamics and Arctic oceanography. We will describe the technology behind this new autonomous platform, which could also be adapted to other applications that require high resolution positioning information with sustained operations and observations in the polar marine environment, and present results pertaining to sea ice dynamics and physical oceanography.
Easton, Roger L.; Hall, David
Richard Corfield's article “Sputnik's legacy” (October 2007 pp23-27) states that the satellite on board the US Vanguard rocket, which exploded during launch on 6 December 1957 two months after Sputnik's successful take-off, was “a hastily put together contraption of wires and circuitry designed only to send a radio signal back to Earth”. In fact, the Vanguard satellite was developed over a period of several years and put together carefully using the best techniques and equipment available at the time - such as transistors from Bell Laboratories/Western Electric. The satellite contained not one but two transmitters, in which the crystal-controlled oscillators had been designed to measure both the temperature of the satellite shell and of the internal package.
Macko, S. A.; Tuite, M.; O'Connell, M.
Students in oceanography classes often request more direct exposure to actual ocean situations or field trips. During regular session (13 week) or shorter term (4 week) summer classes such long trips are logistically difficult owing to large numbers of students involved or timing. This new approach to such a course supplement addresses the requests by utilizing local resources and short field trips for a limited number of students (20) to locations in which Ocean experiences are available, and are often supported through education and outreach components. The vision of the class was a mixture of classroom time, readings, along with paper and actual laboratories. In addition short day-long trips to locations where the ocean was "captured" were also used to supplement the experience as well as speakers involved with aquaculture ("cultivated") . Central Virginia is a fortunate location for such a class, with close access for "day travel" to the Chesapeake Bay and numerous field stations, museums with ocean-based exhibits (the Smithsonian and National Zoo) that address both extant and extinct Earth history, as well as national/state aquaria in Baltimore, Washington and Virginia Beach. Furthermore, visits to local seafood markets at local grocery stores, or larger city markets) enhance the exposure to productivity in the ocean, and viability of the fisheries sustainability. The course could then address not only the particulars of the marine science, but also aspects of ethics, including keeping animals in captivity or overfishing of particular species and the special difficulties that arise from captive or culturing ocean populations. In addition, the class was encouraged to post web-based journals of experiences in order to share opinions of observations in each of the settings.
(statistics)? A: Forecast performance is calculated following a thorough post-storm review of all available cyclone with an estimated intensity between 34 and 63 knots is designated a "Tropical Storm." - Extratropical ETT - Extratropical Transition FT - Final T-Number (Dvorak) IR - Infrared satellite imagery KT
Full Text Available Oceanography as a science is still not very widespread in Brazilian society, making it difficult to strengthen the ties between society and the ocean. Thus, the creation of methodologies associated with new teaching techniques, improved with the help of technology, may build a more inclusive society and provide the experience of oceanographic phenomena for all. The extension project "Ocean for all", executed between March and July of 2016, performed an experience in oceanography to the elderly members of the Associação Catarinense para Integração do Cego (ACIC in Florianópolis (SC. In order to do so, a methodology was created to pass on knowledge about oceanography in its biological, geological, chemical and physical aspects to the visually impaired. During the execution of the experience, as well as the development of the methodology, problems in the coastal marine environment with anthropological origin were presented.
Yamada, M.; Ren, Y.; Ji, H.; Gerhardt, S.; Darfman, S.
With the recent upgrade of the MRX (Magnetic Reconnection Experiment) device, our experimental operation allows us to carry out a jog experiment in which a current sheet can be moved swiftly across an inserted probe assembly. A cluster of probes with variable distances can be inserted into a known desired position in the MRX device. This setup can be similar to the situation in which a cluster of satellites encounters a rapidly moving reconnection layer. If necessary, we can create a neutral sheet where the density of one side is significantly higher than the other, as is the case for the magnetopause. A variable guide field will be applied to study its effect on reconnection. We proposed to document basic patterns of data during a simulated encounter of the MRX reconnection layer with the four-probe mock-up system and compare them with data acquired from past satellites. Relative position of the MMS satellites in the magnetosphere can then be determined. Optimum cluster configuration or distance between the four satellites can be determined for various diagnostics or research missions. The relationship of magnetic fluctuations with the observed out-of- plane quadrupole field, a characteristic signature of the Hall MHD, can be also studied in this series of experiments. In this paper, results from a preliminary experiment will be presented. These experiments utilize effectively the unique MRX ability to accurately know the location of diagnostics with respect to the moving reconnection layer. Supported by DoE, NASA, NSF. M. Yamada et al, Phys. Plasmas 13, 052119 (2006), M.Yamada et al, MMS-IDS proposal (2006), H. Ji et al, Phys. Rev. Letts. 92, 115001 (2004)
The DIALOG Program was founded by the American Society of Limnology and Oceanography (ASLO), in order to reduce the historical, institutional and philosophical barriers that limit the exchange of information between limnologists and oceanographers, and to foster interdisciplinary and inter-institutional research. This was achieved by targeting a recent cohort of Ph.D. recipients whose work included a biological component of limnology or oceanography. The program included: (1) publication of the submitted Ph.D. dissertation abstracts; (2) a symposium to facilitate exchange across institutions and disciplines; and (3) establishment of a centralized data base for applicant characterization and tracking.
Theil, Hjalmar; Weikert, Horst
1. In 1977, 1979 and 1980-81, investigations were carried out which aimed at evaluating the potential risks from mining metalliferous muds precipating in the Atlantis II Deep of the central Red Sea. This environmental research was initiated by the Saudi Sudanese Red Sea Joint Commission in order to avoid any danger for the Red Sea ecosystem. The broad environmental research programme coherent studies in physical, chemical, biological, and geological oceanography as well as toxicological investigations in the oceanic and in reef zones. We summarise the results from our biological fiels studies in the open sea. 2. The biological investigations were concentrated on the area of the Atlantis II Deep. Benthos was sampled between 700-2000m. For comparison a few samples were also taken further north in the central Red Sea, and to east and west along the flanking deep terraces (500-1000m). Plankton studies covered the total water column above the Deep, and were extended along the axial through to north and south. 3. Benthos sampling was carried out using a heavy closing trawl, a large box grab (box size 50 × 50 cm), Van Veen grabs and traps; photographic surveys were made a phototrap and a photosled. Community respiration was measured with a ship-board method using grab subsamples. Nutrient concentrations, seston and phytoplankton standing stocks as well as in situ primary production were determined from hydrocast samples. Data on zooplankton and micronekton composition and standing stock were obtained from samples collected using different multiple opening-and-closing nets equipped with 100 μm, 300 μm, and 1000 μm mesh sizes. Daily and ontogenetical vertical migration patterns were studied by comparisons of data from midday and midnight tows. 4. Throughout the whole area the sediment is a pteropod ooze containing low contentrations of organic matter; measured organic carbon and nitrogen contents were 0.5 and 0.05% respectively, and chloroplastic pigment equivalents
In the fall of 2009, I spent 6 weeks aboard the Coast Guard Icebreaker Healy on a mapping expedition in the Arctic Ocean, through participation in the University of Rhode Island's ARMADA Project. Because I grew up in the Midwest, went to college here, and teach in the Chicago suburbs, I had limited first-hand experience in oceanography, as did most of my students. During my time aboard the ship, I primarily served as a member of the mapping team, collecting bathymetric and seismic data. My other science activities included aiding geologists and acoustic engineers in dredging projects and deployment of under-ice recording devices. I collected water data, sent off weather balloons, and assisted marine mammal observers. For the ARMADA Project I kept an on-line journal, which had a far-reaching impact. Students in many schools kept track of my activities and communicated with me via e-mail. Colleagues and friends shared the journal through other media, such as Facebook. Several of my entries were published in blogs belonging to NOAA and the USGS. I received a grant for renting a satellite phone, and through it was able to make "Live from the Arctic" phone calls. After introductory PowerPoints I communicated with more than 420 students in 5 schools in 3 states. When I returned, I made a series of presentations about the Arctic and my adventures to hundreds of people and was featured in an educational magazine with a circulation of more than 90,000. I also participated in an in-depth mentoring program with a new teacher to help her succeed during the first years of her career. The results: My students and I now have a direct connection to the Arctic and to the fields of oceanography, acoustic engineering, and geology. On their own initiative, students have developed individual projects exploring aspects of my research. They have attended presentations from the Extreme Ice Center and have become involved in drilling issues in the Chukchi Sea. A group of students is
Richardson, A.; Jasnow, M.; Srinivasan, M.; Rosmorduc, V.; Blanc, F.
The TOPEX/Poseidon and Jason-1 ocean altimeter missions offer the educator in the middle school or informal education venue a unique opportunity for reinforcing ocean science studies. An educational poster from NASA's Jet Propulsion Laboratory and France's Centre National d'Etudes Spatiales provide teachers and students a tool to examine topics such as the dynamics of ocean circulation, ocean research, and the oceans' role in climate.
Desa, E.S.; Desai, R.G.P.; DeSa, E.J.
Oceanographic data collected on a research vessel has been transmitted to a shore laboratory using the INMARSAT maritime satellite The system configuration used, consisted of Satellite Communication Terminals interfaced to desk top computers...
Gower, J. F. R.
The ERTS-1 color composite picture of the Vancouver-Victoria region illustrates the value of ERTS data for coastal oceanography. The water of the Fraser River plume which is so clearly visible in the center of the scene has been of interest to oceanographers on the west coast of Canada for a long time as an easily visible tracer of surface water circulation in the strait of Georgia. Maps of the plume at different states of the tide and with different river flow and weather were compiled from oblique aerial photographs in 1950 and used in the siting of sewage and other outfalls in the Vancouver area. More recently high level aerial photomosaics have been used to map the plume area, but the plume can spread over distances of 30 to 40 miles and many photographs, with the uneven illumination inherent in wide angle coverage, are needed for the mosaic. The ERTS satellite gives the first complete view of the plume area. Electronic enhancement of the images shows that the satellite's narrow angle coverage allows very weak surface turbidity features to be made visible to give information on surface currents over a wide area.
This grant supported a successful international multidisciplinary scientific meeting addressing the topic "Coastal and Marginal Seas," hosted by The Oceanography Society and UNESCO's Intergovernmental...
te Raa, L. A; Lam, F. P; Schouten, M. W
.... Possible applications of operational oceanography in REA include improved sonar performance predictions with three-dimensional sound speed forecasts, support of AUV mission planning with the help...
Dimitriou, D.; Sharfstein, P.; Ignaszewski, M.; Clancy, M.
The U.S. Navy's Fleet Numerical Meteorology and Oceanography Center (FNMOC; see http://www.fnmoc.navy.mil/), located in Monterey, CA, is the lead activity within the U.S. Department of Defense (DoD) for numerical weather prediction and coupled air-sea modeling. FNMOC fulfills this role through means of a suite of sophisticated global and regional meteorological and oceanographic (METOC) models, extending from the top of the atmosphere to the bottom of the ocean, which is supported by one of the world's most complete real-time METOC databases. Fleet Numerical operates around-the-clock, 365 days per year and distributes METOC products to military and civilian users around the world, both ashore and afloat, through a variety of means, including a rapidly growing and innovative use of Web technology. FNMOC's customers include all branches of the Department of Defense (DoD), other government organizations such as the National Weather Service, private companies such as the Weather Channel, a number of colleges and universities, and the general public. FNMOC acquires and processes over 6 million METOC observations per day—creating one of the world's most comprehensive real-time databases of meteorological and oceanographic observations for assimilation into its models. FNMOC employs three primary models, the Navy Operational Global Atmospheric Prediction System (NOGAPS), the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS), and the WaveWatch III model (WW3), along with a number of specialized models and related applications. NOGAPS is a global weather model, driving nearly all other FNMOC models and applications in some fashion. COAMPS is a high-resolution regional model that has proved to be particularly valuable for forecasting weather and ocean conditions in highly complex coastal areas. WW3 is a state-of-the-art ocean wave model that is employed both globally and regionally in support of a wide variety of naval operations. Specialized models support and
Arab Organization for Education and Science, Cairo (Egypt).
This document presents four courses for the diploma of higher studies in oceanography conducted by the Department of Oceanography, Faculty of Science, University of Alexandria, Egypt. These courses are organized by the Arab League Educational, Cultural and Scientific Organization (ALECSO). Each course is designed to be taught in one academic year…
This document overviews the areas of current research at Brookhaven National Laboratory. Technology transfer and the user facilities are discussed. Current topics are presented in the areas of applied physics, chemical science, material science, energy efficiency and conservation, environmental health and mathematics, biosystems and process science, oceanography, and nuclear energy. (GHH)
Dmochowski, J. E.; Marinov, I.
A decline in enrollment in STEM fields at the university level has prompted extensive research on alternative ways of teaching and learning science. Inquiry-based learning as well as the related "flipped" or "active" lectures, and similar teaching methods and philosophies have been proposed as more effective ways to disseminate knowledge in science classes than the traditional lecture. We will provide a synopsis of our experiences in implementing some of these practices into our Introductory Oceanography, Global Climate Change, and Ocean Atmosphere Dynamics undergraduate courses at the University of Pennsylvania, with both smaller and larger enrollments. By implementing tools such as at-home modules; computer labs; incorporation of current research; pre- and post-lecture quizzes; reflective, qualitative writing assignments; peer review; and a variety of in-class learning strategies, we aim to increase the science literacy of the student population and help students gain a more comprehensive knowledge of the topic, enhance their critical thinking skills, and correct misconceptions. While implementing these teaching techniques with college students is not without complications, we argue that a blended class that flexibly and creatively accounts for class size and science level improves the learning experience and the acquired knowledge. We will present examples of student assignments and activities as well as describe the lessons we have learned, and propose ideas for moving forward to best utilize innovative teaching tools in order to increase science literacy in oceanography and other climate-related courses.
Gong, Fang; Wang, Difeng; Huang, Haiqing; Chen, Jianyu
From 2002 to 2004, a satellite data processing system for marine application had been built up in State Key Laboratory of Satellite Ocean Environment Dynamics (Second Institute of Oceanography, State Oceanic Administration). The system received satellite data from TERRA, AQUA, NOAA-12/15/16/17/18, FY-1D and automatically generated Level3 products and Level4 products(products of single orbit and merged multi-orbits products) deriving from Level0 data, which is controlled by an operational control sub-system. Currently, the products created by this system play an important role in the marine environment monitoring, disaster monitoring and researches. Now a distribution platform has been developed on this foundation, namely WebGIS system for querying and browsing of oceanic remote sensing data. This system is based upon large database system-Oracle. We made use of the space database engine of ArcSDE and other middleware to perform database operation in addition. J2EE frame was adopted as development model, and Oracle 9.2 DBMS as database background and server. Simply using standard browsers(such as IE6.0), users can visit and browse the public service information that provided by system, including browsing for oceanic remote sensing data, and enlarge, contract, move, renew, traveling, further data inquiry, attribution search and data download etc. The system is still under test now. Founding of such a system will become an important distribution platform of Chinese satellite oceanic environment products of special topic and category (including Sea surface temperature, Concentration of chlorophyll, and so on), for the exaltation of satellite products' utilization and promoting the data share and the research of the oceanic remote sensing platform.
Allison, M. D.; Chandler, C. L.; Groman, R. C.; Wiebe, P. H.; Glover, D. M.; Gegg, S. R.
Oceanography and marine ecosystem research are inherently interdisciplinary fields of study that generate and require access to a wide variety of measurements. In late 2006 the Biological and Chemical Oceanography Sections of the National Science Foundation (NSF) Geosciences Directorate Division of Ocean Sciences (OCE) funded the Biological and Chemical Oceanography Data Management Office (BCO-DMO). In late 2010 additional funding was contributed to support management of research data from the NSF Office of Polar Programs Antarctic Organisms & Ecosystems Program. The BCO-DMO is recognized in the 2011 Division of Ocean Sciences Sample and Data Policy as one of several program specific data offices that support NSF OCE funded researchers. BCO-DMO staff members offer data management support throughout the project life cycle to investigators from large national programs and medium-sized collaborative research projects, as well as researchers from single investigator awards. The office manages and serves all types of oceanographic data and information generated during the research process and contributed by the originating investigators. BCO-DMO has built a data system that includes the legacy data from several large ocean research programs (e.g. United States Joint Global Ocean Flux Study and United States GLOBal Ocean ECosystems Dynamics), to which data have been contributed from recently granted NSF OCE and OPP awards. The BCO-DMO data system can accommodate many different types of data including: in situ and experimental biological, chemical, and physical measurements; modeling results and synthesis data products. The system enables reuse of oceanographic data for new research endeavors, supports synthesis and modeling activities, provides availability of "real data" for K-12 and college level use, and provides decision-support field data for policy-relevant investigations. We will present an overview of the data management system capabilities including: map
The oceanography programme of the Federal German Government has the following general aims: 1. To lay the foundation for better understanding of the role of the ocean as a climate factor and repercussions on the ocean from climate change as a basis for future preventive and protective action. 2. Identification of natural and anthropogenous factors of stress to the coastal seas, the coastal regions and the open ocean, research into their dynamics and impact, and development of bases, methods and concepts for describing and evaluating the condition of the coastal seas, coastal regions and open ocean and for projecting and/or remedying relative changes. 3. Development of methods and techniques for climate and environment-related research into and monitoring of the oceans and for careful exploitation of living and non-living resources. (orig.) [de
Full Text Available To understand the seasonal variation of biological and biogeochemical cycles in the seasonal ice zone in the Southern Ocean, the cruise of JARE-STAGE (Japanese Antarctic Research Expedition-Studies on Antarctic Ocean and Global Environment was conducted in February 2002 with R/V Tangaroa. Physical oceanography implementations of the cruise are described. The results of the manufacturers' CTD conductivity calibrations were consistent between before and after the cruise, and the difference in salinity estimate was expected to be within 0.0014. Two casts were made to validate the XCTD accuracy and comparisons with the CTD are discussed. Generally, it is concluded that reasonably accurate observations were completed in this cruise.
Allison, M. D.; Chandler, C. L.; Copley, N.; Galvarino, C.; Gegg, S. R.; Glover, D. M.; Groman, R. C.; Wiebe, P. H.; Work, T. T.; Biological; Chemical Oceanography Data Management Office
Ocean biogeochemistry and marine ecosystem research projects are inherently interdisciplinary and benefit from improved access to well-documented data. Improved data sharing practices are important to the continued exploration of research themes that are a central focus of the ocean science community and are essential to interdisciplinary and international collaborations that address complex, global research themes. In 2006, the National Science Foundation Division of Ocean Sciences (NSF OCE) funded the Biological and Chemical Oceanography Data Management Office (BCO-DMO) to serve the data management requirements of scientific investigators funded by the National Science Foundation’s Biological and Chemical Oceanography Sections. BCO-DMO staff members work with investigators to manage marine biogeochemical, ecological, and oceanographic data and information developed in the course of scientific research. These valuable data sets are documented, stored, disseminated, and protected over short and intermediate time frames. One of the goals of the BCO-DMO is to facilitate regional, national, and international data and information exchange through improved data discovery, access, display, downloading, and interoperability. In May 2010, NSF released a statement to the effect that in October 2010, it is planning to require that all proposals include a data management plan in the form of a two-page supplementary document. The data management plan would be an element of the merit review process. NSF has long been committed to making data from NSF-funded research publicly available and the new policy will strengthen this commitment. BCO-DMO is poised to assist in creating the data management plans and in ultimately serving the data and information resulting from NSF OCE funded research. We will present an overview of the data management system capabilities including: geospatial and text-based data discovery and access systems; recent enhancements to data search tools; data
Within the tasks devoted to operational oceanography, Coastal Ocean Observatory at Institut de Ciències del Mar (CSIC) has acquired an European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Broadcast System for Environmental Data (EUMETCast reception system) to replace a satellite direct broadcast system that receives data via High Resolution Picture Transmission (HRPT). EUMETCast system can receive data based on standard Digital Video Broadcastin...
meteorological satellite is stated in this paper. exploration of the ocean resources has been a very important question of global strategy in the world. The exploration of the ocean resources includes following items: Making full use of oceanic resources and space, protecting oceanic environment. to observe the ocean is by using of satellite. In 1978, US successfully launched the first ocean observation satellite in the world --- Sea Satellite. It develops ancient oceanography in to advanced space-oceanography. FY-1 B and FY- IC respectively. High quality data were acquired at home and abroad. FY-1 is Chinese meteorological satellite, but with 0.43 ~ 0.48 μm ,0.48 ~ 0.53 μm and 0.53 ~ 0.58 μm three ocean color channels, actually it is a multipurpose remote sensing satellite of meteorology and oceanography. FY-1 satellite's capability of observation on ocean partly, thus the application field is expanded and the value is increased. With the addition of oceanic channels on FY-1, the design of the satellite is changed from the original with meteorological observation as its main purpose into remote sensing satellite possessing capability of observing meteorology and ocean as well. Thus, the social and economic benefit of FY-1 is increased. the social and economic benefit of the development of the satellite is the key technique in the system design of the satellite. technically feasible but also save the funds in researching and manufacturing of the satellite, quicken the tempo of researching and manufacturing satellite. the scanning radiometer for FY-1 is conducted an aviation experiment over Chinese ocean. This experiment was of vital importance to the addition of oceanic observation channel on FY-1. FY-1 oceanic channels design to be correct. detecting ocean color. This is the unique character of Chinese FY-1 meteorological satellite. meteorological remote sensing channel on FY-1 to form detecting capability of three visible channels: red, yellow and blue
Carey, William M.
Recent societal concerns have focused attention on the use of sound as a probe to investigate the oceans and its use in naval sonar applications. The concern is the impact the use of sound may have on marine mammals and fishes. The focus has changed the fields of acoustical oceanography (AO) and underwater acoustics (UW) because of the requirement to communicate between disciplines. Multiple National Research Council publications, Dept. of Navy reports, and several monographs have been written on this subject, and each reveals the importance as well as the misapplication of ASA standards. The ANSI-ASA standards are comprehensive, however not widely applied. The clear definition of standards and recommendations of their use is needed for both scientists and government agencies. Traditionally the U.S. Navy has been responsible for UW standards and calibration; the ANSI-ASA standards have been essential. However, recent changes in the Navy and its laboratory structure may necessitate a more formal recognition of ANSI-ASA standards and perhaps incorporation of UW-AO in the Bureau of Standards. A separate standard for acoustical terminology, reference levels, and notation used in the UW-AO is required. Since the problem is global, a standard should be compatible and cross referenced with the International Standard (CEI/IEC 27-3).
Federal Laboratory Consortium — The ARDEC Satellite Facility is a 24-hour on-site military satellite transmission and downlink capability to Southwest Asia and all other military OCONUS and CONUS...
Gross, Rachel; Melkers, Raimond
The U.S. Naval Research Laboratory has installed GPS-based timing systems in several Defense Satellite Communication System "DSCS-III" satellite communication facilities to support the Single Channel Transponder "SCT" program...
National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to develop spatially discrete end-to-end models of the California Current LME, linking oceanography, biogeochemistry, food web...
Tapaswi, M.P.; Maheswarappa, B.S.
An analysis of serials preferred and cited in various communications by the Indian oceanographers during 1963 to 1992 is presented. A shift in preference of serials from general sciences to oceanography (interdisciplinary) and to core subject...
National Oceanic and Atmospheric Administration, Department of Commerce — The University of California San Diego (UCSD) Scripps Institution of Oceanography (SIO) is a partner in the Index to Marine and Lacustrine Geological Samples (IMLGS)...
Sánchez-Arcilla, Agustín; Carniel, Sandro; Badger, Merete; Bidlot, Jean; Boye Hansen, Lars; Bolaños-Sanchez, Rodolfo; Cipollini, Paolo; Espino, Manuel; Marcello Miglietta, Mario; Saulter, Andy; Staneva, Joanna
The increasing quality and quantity (resolution in space, coverage in time, combinations of sensors in the Sentinel family) of information provided by Copernicus offer the possibility to analyse and predict coastal meteo-oceanography at an unprecedented level. This is a unique opportunity to develop the Copernicus coastal dimension to tackle the pressures of increasing population and activities. The combination of ocean/atmosphere/land observations from the Sentinel (S) 1/2/3, aligned with the availability of an increasing number of high-resolution numerical simulations (e.g. wave and current fields) in the Copernicus Marine Environment Monitoring Service (CMEMS) catalogue, should allow users to access proven representations of the coastal environment at a new level of understanding (e.g. wave diffraction at coastal "obstacles"), coupling (e.g. incorporating the land discharge into the coastal sea) and reliability for applications (e.g. hazards for coastal navigation). By adding periodic bathymetric up-dating and incorporating new assimilation routines it will be possible to achieve a new level of analysis for coastal seas. In the paper we shall present the CEASELESS project that addresses the multiple scales coexisting in littoral areas by developing new shallow water parameterizations, introducing them into coupled model suites (wind-wave-surge-current-land discharge) and producing new standards for coastal simulations and analyses. This will demonstrate the technical feasibility of an operational coastal service. The set of derived products will be ingested into the users' work routines, proving the economic feasibility of such a coastal extension. The level of conflicts in squeezed coastal zones, expected to grow in the face of climate change, will, thus, benefit directly from CEASELESS, establishing tangible contributions for a wide range of economic sectors. The mutual validation of satellite data, numerical results and in-situ observations will generate
Progress is reported in the following areas: laser weapon effects, solar silicon solar cell concepts, and high voltage hardened, high power system technology. Emphasis is placed on solar cells with increased energy conversion efficiency and radiation resistance characteristics for application to satellite power systems.
Federal Laboratory Consortium — FUNCTION: The Blossom Point Satellite Command and Tracking Facility (BP) provides engineering and operational support to several complex space systems for the Navy...
Full Text Available One of the fundamental problems of modern geodesy is precise definition of the gravitational field and its changes in time. This is essential in positioning and navigation, geo-physics, geodynamics, oceanography and other sciences related to the climate and Earth’s environment. One of the major sources of gravity data is satellite altimetry that provides gravity data with almost 75% surface of the Earth. Satellite altimetry also provides data to study local, regional and global geophysical processes, the geoid model in the areas of oceans and seas. This technique can be successfully used to study the ocean mean dynamic topography. The results of the investigations and possible products of altimetry will provide a good material for the GGOS (Global Geodetic Observing System and institutions of IAS (International Altimetry Service.
The many scientific achievements of the Nimbus series of seven satellites for low-altitude atmospheric research and global weather surveillance are reviewed. The series provides information on fishery resources, weather modeling, atmospheric pollution monitoring, earth's radiation budget, ozone monitoring, ocean dynamics, and the effects of cloudiness. Data produced by the forty-eight instruments and sensors flown on the satellites are applied in the fields of oceanography, hydrology, geology, geomorphology, geography, cartography, agriculture and meteorology. The instruments include the Coastal Zone Color Scanner (which depicts phytoplankton concentrations in coastal areas), the Scanning Multichannel Microwave Radiometer (which measures sea-surface temperatures and sea-surface wind-speed), and the Total Ozone Mapping Spectrometer (which provides information on total amounts of ozone in the earth's atmosphere).
The characteristics of the Saturn satellites are discussed. The satellites close to Saturn - Janus, Mimas, Enceladus, Tethys, Dione and Rhea - rotate along the circular orbits. High reflectivity is attributed to them, and the density of the satellites is 1 g/cm 3 . Titan is one of the biggest Saturn satellites. Titan has atmosphere many times more powerful than that of Mars. The Titan atmosphere is a peculiar medium with a unique methane and hydrogen distribution in the whole Solar system. The external satellites - Hyperion, Japetus and Phoebe - are poorly investigated. Neither satellite substance density, nor their composition are known. The experimental data on the Saturn rings obtained on the ''Pioneer-11'' and ''Voyager-1'' satellites are presented [ru
Groman, R. C.; Chandler, C.; Allison, D.; Glover, D. M.; Wiebe, P. H.
The Biological and Chemical Oceanography Data Management Office (BCO-DMO) was created to serve PIs principally funded by NSF to conduct marine chemical and ecological research. The new office is dedicated to providing open access to data and information developed in the course of scientific research on short and intermediate time-frames. The data management system developed in support of U.S. JGOFS and U.S. GLOBEC programs is being modified to support the larger scope of the BCO-DMO effort, which includes ultimately providing a way to exchange data with other data systems. The open access system is based on a philosophy of data stewardship, support for existing and evolving data standards, and use of public domain software. The DMO staff work closely with originating PIs to manage data gathered as part of their individual programs. In the new BCO-DMO data system, project and data set metadata records designed to support re-use of the data are stored in a relational database (MySQL) and the data are stored in or made accessible by the JGOFS/GLOBEC object- oriented, relational, data management system. Data access will be provided via any standard Web browser client user interface through a GIS application (Open Source, OGC-compliant MapServer), a directory listing from the data holdings catalog, or a custom search engine that facilitates data discovery. In an effort to maximize data system interoperability, data will also be available via Web Services; and data set descriptions will be generated to comply with a variety of metadata content standards. The office is located at the Woods Hole Oceanographic Institution and web access is via http://www.bco-dmo.org.
Gavili Kilaneh, Narin; Mashhadi Hossainali, Masoud
Due to the recent advances in the Global Navigation Satellite System Remote sensing (GNSS¬R) applications, optimization of a satellite orbit to investigate the Earth's properties seems significant. The comparison of the GNSS direct and reflected signals received by a Low Earth Orbit (LEO) satellite introduces a new technique to remotely sense the Earth. Several GNSS¬R missions including Cyclone Global Navigation Satellite System (CYGNSS) have been proposed for different applications such as the ocean wind speed and height monitoring. The geometric optimization of the satellite orbit before starting the mission is a key step for every space mission. Since satellite constellation design varies depending on the application, we have focused on the required geometric criteria for oceanography applications in a specified region. Here, the total number of specular points, their spatial distribution and the accuracy of their position are assumed to be sufficient for oceanography applications. Gleason's method is used to determine the position of specular points. We considered the 2-D lattice and 3-D lattice theory of flower constellation to survey whether a circular orbit or an elliptical one is suitable to improve the solution. Genetic algorithm is implemented to solve the problem. To check the visibility condition between the LEO and GPS satellites, the satellite initial state is propagated by a variable step size numerical integration method. Constellation orbit parameters achieved by optimization provide a better resolution and precession for the specular points in the study area of this research.
Łyszkowicz Adam Bolesław
Full Text Available One of the fundamental problems of modern geodesy is precise defi nition of the gravitational fi eld and its changes in time. This is essential in positioning and navigation, geophysics, geodynamics, oceanography and other sciences related to the climate and Earth’s environment. One of the major sources of gravity data is satellite altimetry that provides gravity data with almost 75% surface of the Earth. Satellite altimetry also provides data to study local, regional and global geophysical processes, the geoid model in the areas of oceans and seas. This technique can be successfully used to study the ocean mean dynamic topography. The results of the investigations and possible products of altimetry will provide a good material for the GGOS (Global Geodetic Observing System and institutions of IAS (International Altimetry Service. This paper presents the achievements in satellite altimetry in all the above disciplines obtained in the last years. First very shorly basic concept of satellite altimetry is given. In order to obtain the highest accuracy on range measurements over the ocean improved of altimetry waveforms performed on the ground is described. Next, signifi cant improvements of sea and ocean gravity anomalies models developed presently is shown. Study of sea level and its extremes examined, around European and Australian coasts using tide gauges data and satellite altimetry measurements were described. Then investigations of the phenomenon of the ocean tides, calibration of altimeters, studies of rivers and ice-sheets in the last years are given.
Łyszkowicz, Adam Bolesław; Bernatowicz, Anna
One of the fundamental problems of modern geodesy is precise defi nition of the gravitational fi eld and its changes in time. This is essential in positioning and navigation, geophysics, geodynamics, oceanography and other sciences related to the climate and Earth's environment. One of the major sources of gravity data is satellite altimetry that provides gravity data with almost 75% surface of the Earth. Satellite altimetry also provides data to study local, regional and global geophysical processes, the geoid model in the areas of oceans and seas. This technique can be successfully used to study the ocean mean dynamic topography. The results of the investigations and possible products of altimetry will provide a good material for the GGOS (Global Geodetic Observing System) and institutions of IAS (International Altimetry Service). This paper presents the achievements in satellite altimetry in all the above disciplines obtained in the last years. First very shorly basic concept of satellite altimetry is given. In order to obtain the highest accuracy on range measurements over the ocean improved of altimetry waveforms performed on the ground is described. Next, signifi cant improvements of sea and ocean gravity anomalies models developed presently is shown. Study of sea level and its extremes examined, around European and Australian coasts using tide gauges data and satellite altimetry measurements were described. Then investigations of the phenomenon of the ocean tides, calibration of altimeters, studies of rivers and ice-sheets in the last years are given.
Tollenaere, Maxim A X; Mailand, Niels; Bekker-Jensen, Simon
Centriolar satellites are small, microscopically visible granules that cluster around centrosomes. These structures, which contain numerous proteins directly involved in centrosome maintenance, ciliogenesis, and neurogenesis, have traditionally been viewed as vehicles for protein trafficking...... highlight newly discovered regulatory mechanisms targeting centriolar satellites and their functional status, and we discuss how defects in centriolar satellite components are intimately linked to a wide spectrum of human diseases....
Pockalny, R. A.; Donohue, K. A.; Fliegler, J.
The Summer Undergraduate Research Fellowships in Oceanography (SURFO) program at the Graduate School of Oceanography/University of Rhode Island is an NSF-funded Research Experience for Undergraduates site program with a programmatic research niche focused on quantitative aspects of Oceanography. Each summer-cohort includes 9-12 participants (rising seniors) who are paired with a primary research advisor and often with a graduate student mentor. The primary components of the 10-week program include a 4-week introductory phase and a 6-week core research phase. A retrospective self-assessment instrument gauged the confidence, attitude and comfort level of participants with; 1) core math and science subjects, 2) oceanography-related subjects, 3) research skills, and 4) SURFO and GSO staff. SURFO participants evaluated themselves at the start of the program, after the introductory phase, and at the end of the program. Participants were also asked to reassess their initial evaluations and provide an updated score. The pre-assessment results indicate that the program recruits students from the target group (e.g., strong physics and math backgrounds, but with limited exposure to oceanography). The results also indicate that the students are initially comfortable with their advising team, but not so comfortable with their research topic and research skills. The post-introductory phase results indicate large increases in comfort level with the advising team and the local research community yet little or no change is indicated for research skills. The final assessments show large changes in oceanography-content knowledge, research topic, and research skills. The retrospective reassessment indicates an initial overconfidence in most categories. Overall, the largest changes occurred during the core research portion of the program. These results reinforce the importance/effectiveness of authentic, hands-on, inquiry-based research for higher learning and training the next
Science communication through the use of social media is a rapidly evolving and growing pursuit in academic and scientific circles. Online tools and social media are being used in not only scientific communication but also scientific publication, education, and outreach. Standards and usage of social media as well as other online tools for communication, networking, outreach, and publication are always in development. Caution and a conservative attitude towards these novel "Science 2.0" tools is understandable because of their rapidly changing nature and the lack of professional standards for using them. However there are some key benefits and unique ways social media, online systems, and other Open or Open Source technologies, software, and "Science 2.0" tools can be utilized for academic purposes such as education and outreach. Diverse efforts for ocean conservation and education will continue to utilize social media for a variety of purposes. The BioOceanography project is an informal communication, education, outreach, and conservation initiative created for enhancing knowledge related to Oceanography and Marine Science with an unbiased yet conservation-minded approach and in an Open Source format. The BioOceanography project is ongoing and still evolving, but has already contributed to ocean education and conservation communication in key ways through a concerted web presence since 2013, including a curated Twitter account @_Oceanography and BioOceanography blog style website. Social media tools like those used in this project, if used properly can be highly effective and valuable for encouraging students, networking with researchers, and educating the general public in Oceanography.
Reed, D. L.
All general education courses at the San Jose State University, including those in the sciences, must present a detailed assessment plan of student learning, prior to certification for offering. The assessment plan must state a clear methodology for acquiring data on student achievement of the learning outcomes for the specific course category, as well as demonstrate how students fulfill a strong writing requirement. For example, an online course in oceanography falls into the Area R category, the Earth and Environment, through which a student should be able to demonstrate an understanding of the methods and limits of scientific investigation; distinguish science from pseudo-science; and apply a scientific approach to answer questions about the Earth and environment. The desired learning outcomes are shared with students at the beginning of the course and subsequent assessments on achieving each outcome are embedded in the graded assignments, which include a critical thinking essay, mid-term exam, poster presentation in a symposium-style format, portfolio of web-based work, weekly discussions on an electronic bulletin board, and a take-home final exam, consisting of an original research grant proposal. The diverse nature of the graded assignments assures a comprehensive assessment of student learning from a variety of perspectives, such as quantitative, qualitative, and analytical. Formative assessment is also leveraged into learning opportunities, which students use to identify the acquisition of knowledge. For example, pre-tests are used to highlight preconceptions at the beginning of specific field studies and post-testing encourages students to present the results of small research projects. On a broader scale, the assessment results contradict common misperceptions of online and hybrid courses. Student demand for online courses is very high due to the self-paced nature of learning. Rates of enrollment attrition match those of classroom sections, if students
Bolanos, Rodolfo; Jensen, Palle; Kofoed-Hansen, Henrik; Tornsfeldt Sørensen, Jacob
Coastal processes imply the interaction of the atmosphere, the sea, the coastline and the bottom. The spatial gradients in this area are normally large, induced by orographic and bathymetric features. Although nowadays it is possible to obtain high-resolution bathymetry, the details of the seabed, e.g. sediment type, presence of biological material and living organisms are not available. Additionally, these properties as well as bathymetry can also be highly dynamic. These bottom characteristics are very important to describe the boundary layer of currents and waves and control to a large degree the dissipation of flows. The bottom friction is thus typically a calibration parameter in numerical modelling of coastal processes. In this work, we assess this process and put it into context of other physical processes uncertainties influencing wind-waves and currents in the coastal areas. A case study in the North Sea is used, particularly the west coast of Denmark, where water depth of less than 30 m cover a wide fringe along the coast, where several offshore wind farm developments are being carried out. We use the hydrodynamic model MIKE 21 HD and the spectral wave model MIKE 21 SW to simulate atmosphere and tidal induced flows and the wind wave generation and propagation. Both models represent state of the art and have been developed for flexible meshes, ideal for coastal oceanography as they can better represent coastlines and allow a variable spatial resolution within the domain. Sensitivity tests to bottom friction formulations are carried out into context of other processes (e.g. model forcing uncertainties, wind and wave interactions, wind drag coefficient). Additionally, a map of varying bottom properties is generated based on a literature survey to explore the impact of the spatial variability. Assessment of different approaches is made in order to establish a best practice regarding bottom friction and coastal oceanographic modelling. Its contribution is also
. 729-730 September 1999 Book Reviews DATA ANALYSIS METHODS IN PHYSICAL O~EAN~GRAFWY. By Wil- liam J. Emery and Richard E. Thomson. PERGAMON Else&r Sci- ence. 1998. 400 p. U.S. $112 / NLG 177.00. The book Data Analysis Methods in Physical... Oceanography pro- vides a comprehensive and practical compilation of the essential information and analysis techniques required for the advanced processing and interpretation of digital spat&temporal data in physical oceanography, as well as in other...
in Physical Oceanography. Page 1 of 1 file://C:\\My Documents\\articles30.htm 2/11/05 William J. Emery and Richard E. Thomson. Pergamon Elsevier Science. 1998. hardbound. 400 pp. ISBN: 0-08-031434-1. Price: US$ 112/NLG 177.00 This book provides a comprehensive... and practical compilation of the essential information and analysis techniques required for the advanced processing and interpretation of digital spatio-temporal data in physical oceanography, as well as in other branches of the geophysical sciences. The book...
First page Back Continue Last page Overview Graphics. Satellite Communications. Arthur C Clarke wrote a seminal paper in 1945 in wireless world. Use three satellites in geo-synchronous orbit to enable intercontinental communications. System could be realised in '50 to 100 years'
Geostationary Satellites Collocation aims to find solutions for deploying a safe and reliable collocation control. Focusing on the orbital perturbation analysis, the mathematical foundations for orbit and control of the geostationary satellite are summarized. The mathematical and physical principle of orbital maneuver and collocation strategies for multi geostationary satellites sharing with the same dead band is also stressed. Moreover, the book presents some applications using the above algorithms and mathematical models to help readers master the corrective method for planning station keeping maneuvers. Engineers and scientists in the fields of aerospace technology and space science can benefit from this book. Hengnian Li is the Deputy Director of State Key Laboratory of Astronautic Dynamics, China.
Keiner, Louis E.; Gilman, Craig
This study measures the effects of increased faculty-student engagement on student learning, success rates, and perceptions in a Physical Oceanography course. The study separately implemented two teaching methods that had been shown to be successful in a different discipline, introductory physics. These methods were the use of interactive…
Arab Organization for Education and Science, Cairo (Egypt).
This document presents a training course in oceanography intended for Junior Bachelor of Science (B.S.) graduates in physics, mathematics, chemistry, zoology, botany or geology to give them the minimum qualifications required to work in any of the marine science stations. This 14-week course, organized by the Arab League Educational, Cultural and…
Lauro, Frederico; Senstius, Svend Jacob; Cullen, Jay
Microbial Oceanography has long been an extremely expensive discipline, requiring ship time for sample collection and thereby economically constraining the number of samples collected. This is especially true for under-sampled water bodies such as the Indian Ocean. Specialised scientific equipmen...
Included is a detailed outline of the content of each course required or offered as an elective in the associate degree program. With an 18 or 19 unit load each semester the program requires two years, and includes 64 hours at sea every semester. In addition to chemistry, physics, biology, and oceanography courses, there is a required course in…
Pelton, Joseph N
The field of satellite communications represents the world's largest space industry. Those who are interested in space need to understand the fundamentals of satellite communications, its technology, operation, business, economic, and regulatory aspects. This book explains all this along with key insights into the field's future growth trends and current strategic challenges. Fundamentals of Satellite Communications is a concise book that gives all of the key facts and figures as well as a strategic view of where this dynamic industry is going. Author Joseph N. Pelton, PhD, former Dean of the International Space University and former Director of Strategic Policy at Intelstat, presents a r
Olsen, Nils; Stolle, Claudia
Observations of Earth’s magnetic field from space began more than 50 years ago. A continuous monitoring of the field using low Earth orbit (LEO) satellites, however, started only in 1999, and three satellites have taken highprecision measurements of the geomagnetic field during the past decade....... The unprecedented time-space coverage of their data opened revolutionary new possibilities for monitoring, understanding, and exploring Earth’s magnetic field. In the near future, the three-satellite constellation Swarm will ensure continuity of such measurement and provide enhanced possibilities to improve our...... ability to characterize and understand the many sources that contribute to Earth’s magnetic field. In this review, we summarize investigations of Earth’s interior and environment that have been possible through the analysis of high-precision magnetic field observations taken by LEO satellites....
Hesselbrock, Andrew; Minton, David A.
We recently reported that the orbital architecture of the Martian environment allows for material in orbit around the planet to ``cycle'' between orbiting the planet as a ring, or as coherent satellites. Here we generalize our previous analysis to examine several factors that determine whether satellites accreting at the edge of planetary rings will cycle. In order for the orbiting material to cycle, tidal evolution must decrease the semi-major axis of any accreting satellites. In some systems, the density of the ring/satellite material, the surface mass density of the ring, the tidal parameters of the system, and the rotation rate of the primary body contribute to a competition between resonant ring torques and tidal dissipation that prevent this from occurring, either permanently or temporarily. Analyzing these criteria, we examine various bodies in our solar system (such as Saturn, Uranus, and Eris) to identify systems where cycling may occur. We find that a ring-satellite cycle may give rise to the current Uranian ring-satellite system, and suggest that Miranda may have formed from an early, more massive Uranian ring.
Clancy, R. M.
The U.S. Navy's Fleet Numerical Meteorology and Oceanography Center (FNMOC) plays a significant role in the National capability for operational weather and ocean prediction through its operation of sophisticated global and regional meteorological and oceanographic models, extending from the top of the atmosphere to the bottom of the ocean. FNMOC uniquely satisfies the military's requirement for a global operational weather prediction capability based on software certified to DoD Information Assurance standards and operated in a secure classified computer environment protected from outside intrusion by DoD certified firewalls. FNMOC operates around-the-clock, 365 days per year and distributes products to military and civilian users around the world, both ashore and afloat, through a variety of means. FNMOC's customers include all branches of the Department of Defense, other government organizations such as the National Weather Service, private companies, a number of colleges and universities, and the general public. FNMOC employs three primary models, the Navy Operational Global Atmospheric Prediction System (NOGAPS), the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS), and the WaveWatch III model (WW3), along with a number of specialized models and related applications. NOGAPS is a global weather model, driving nearly all other FNMOC models and applications in some fashion. COAMPS is a high- resolution regional model that has proved to be particularly valuable for forecasting weather and ocean conditions in highly complex coastal areas. WW3 is a state-of-the-art ocean wave model that is employed both globally and regionally in support of a wide variety of naval operations. Other models support and supplement the main models with predictions of ocean thermal structure, ocean currents, sea-ice characteristics, and other data. Fleet Numerical operates at the leading edge of science and technology, and benefits greatly from collocation with its supporting
The present document is consider the physical and biological variables important part in the integration of the climatic system, like improvement to the knowledge of the present marine processes in the Colombian marine areas by means of the advantage of the technological resources available at the present time for the obtaining of information in real time of physical and biological processes, agreed to the constitutional mandate of sustainable development. The images of color of the ocean provided by located remote sensors in the satellites allow considering primary the organic productivity of a synoptic way, in great areas. This is of great importance to more effectively support the rational handling of the fishing resources and to make a contribution on the paper of the ocean in the global climatic change. The marine phytoplankton can significantly alter to the carbon interchange in interactions ocean-atmosphere. The marine photosynthesis reduces the partial pressure of superficial water CO 2 , with the result of which a portion of organic carbon just formed (new productivity) sinks outside the afotica zone. The previous thing induces a net effect of carbon flow from the atmosphere to the ocean. One of the potential applications of the use of the images of satellite of color of the ocean is the calculation of the chlorophyll concentration and its relation with the sobreexperience of larvae of fish of commercial interest. Different types from developed mathematical models for concerning oceanic waters in the accomplishment of estimations of primary productivity with base in color images of the ocean exist mainly - time out - for that reason, the necessity of develop model similar for the calculation of the productivity primary of the phytoplankton of the Colombian marine area
support for teaching via blished comprehensive teaching and a large assortment of facilities and research programs, which are con- projects that are... teaching and re- Reichard, and Stephen Riser, joint search laboratories are augmented by appointments with JISAO, and Eric a research fleet consisting of...West. Botanica Marina 23: 333-341. No. 1124 Lewin, J., J.E. Eckman, and G.N. Ware (1979) Blooms of surf-zone diatoms along the coast of the Olympic
Satellites have been a highly effective platform for multi- form broadcasts. This has led to a ... diversity offormats, languages, genre, and a universal reach that cannot be met by .... programs can be delivered to whom it is intended. In the case of.
Rogers, D. B.
Geoscience classrooms have benefitted greatly from the use of interactive, dry-erasable globes to supplement instruction on topics that require three-dimensional visualization, such as seismic wave propagation and the large-scale movements of tectonic plates. Indeed, research by Bamford (2013) demonstrates that using three-dimensional visualization to illustrate complex processes enhances student comprehension. While some geoscience courses tend to bake-in lessons on visualization, other disciplines of earth science that require three-dimensional visualization, such as oceanography, tend to rely on students' prior spatial abilities. In addition to spatial intelligence, education on the three-dimensional structure of the ocean requires knowledge of the external processes govern the behavior of the ocean, as well as the vertical and lateral distribution of water properties around the globe. Presented here are two oceanographic activities that utilize RealWorldGlobes' dry-erase globes to supplement traditional oceanography lessons on thermohaline and surface ocean circulation. While simultaneously promoting basic plotting techniques, mathematical calculations, and unit conversions, these activities touch on the processes that govern global ocean circulation, the principles of radiocarbon dating, and the various patterns exhibited by surface ocean currents. These activities challenge students to recognize inherent patterns within their data and synthesize explanations for their occurrence. Spatial visualization and critical thinking are integral to any geoscience education, and the combination of these abilities with engaging hands-on activities has the potential to greatly enhance oceanography education in both secondary and postsecondary settings
noise signal level exceeds 10 times the normal background. EXPERIMENTS FOR SATELLITE ASTRONOMY 615 ANTENNA MONOPOLE -., PREAMPLFE = BANDPASS-FILTER...OUTPUT TO AND DETECTOR TELEMETRYCHANNELS (18) CALIBRATION NOISE MATRIX CLOCK NOISE SOURCE ’ON’ SOURCE COMMAND F ROM PROGRAMERP ANTENNA MONOPOLE FIGURE 13...Animal Tempera- ture Sensing for Studying the Effect of Prolonged Orbital Flight on the Circadian Rhythms of Pocket Mice . Unmanned Spacecraft Meeting
A reference system design, projected costs, and the functional concepts of a satellite solar power system (SSPS) for converting sunlight falling on solar panels of a satellite in GEO to a multi-GW beam which could be received by a rectenna on earth are outlined. Electricity transmission by microwaves has been demonstrated, and a reference design system for supplying 5 GW dc to earth was devised. The system will use either monocrystalline Si or concentrator GaAs solar cells for energy collection in GEO. Development is still needed to improve the lifespan of the cells. Currently, the cell performance degrades 50 percent in efficiency after 7-8 yr in space. Each SSPS satellite would weigh either 34,000 tons (Si) or 51,000 tons (GaAs), thereby requiring the fabrication of a heavy lift launch vehicle or a single-stage-to-orbit transport in order to minimize launch costs. Costs for the solar panels have been estimated at $500/kW using the GaAs technology, with transport costs for materials to GEO being $40/kg.
A reference system design, projected costs, and the functional concepts of a satellite solar power system (SSPS) for converting sunlight falling on solar panels of a satellite in GEO to a multi-GW beam which could be received by a rectenna on earth are outlined. Electricity transmission by microwaves has been demonstrated, and a reference design system for supplying 5 GW dc to earth was devised. The system will use either monocrystalline Si or concentrator GaAs solar cells for energy collection in GEO. Development is still needed to improve the lifespan of the cells. Currently, the cell performance degrades 50 percent in efficiency after 7-8 yr in space. Each SSPS satellite would weigh either 34,000 tons (Si) or 51,000 tons (GaAs), thereby requiring the fabrication of a heavy lift launch vehicle or a single-stage-to-orbit transport in order to minimize launch costs. Costs for the solar panels have been estimated at $500/kW using the GaAs technology, with transport costs for materials to GEO being $40/kg.
Miller, S.; Hawkins, J.; Turk, J.
The traditional and proper path followed in transitioning research applications to operational support entails a rigorous gamut of quality control, testing, validation, technical documentation, and software optimization. In times of dire need when observations are in high demand and resources are few, however, convention must sometimes give way to outside-of-the-box thinking. Here, considerations made for manageable compromises forge a pathway to accelerated transition of developing technologies. Such was the case in Coalition mobilizations immediately following the 9/11 attacks, when the United States Office of Naval Research issued a challenge to the environmental research and development community to expedite the delivery of any and all capabilities bearing support relevance to mission planners and executors involved in the increasingly likely military response. It was under this directive that the Naval Research Laboratory's (NRL) Satellite Meteorological Applications Section reconfigured its base research program and internal processing infrastructure to effectively transform itself into an agile operational production system for rapid transition of value-added satellite environmental characterization products centered around next-generation 'research grade' satellite observing systems. Integral to this transformation was the coincident establishment of the Near Real-Time Processing Effort (NRTPE) coordinated among members of the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), and Department of Defense (DoD; Air Force and Navy participants) working in a 'badgeless environment'. The NRTPE provided a portal for acquisition of NASA's MODerate resolution Imaging Spectroradiometer (MODIS) data at 2-4 hr latency worldwide. By virtue of NRTPE modifications to the Terra and Aqua satellite telemetry downlinks and transmission across the high-speed Defense Research/Engineering Network, data previously
Thomas, S. F.; McAdoo, D. C.; Farrell, S. L.; Brozena, J. M.; Childers, V. A.; Ziebart, M. K.; Shepherd, A.
The circulation of the Arctic Ocean is of great interest to both the oceanographic and cryospheric communities. Understanding both the steady state and variations of this circulation is essential to building our knowledge of Arctic climate. With the advent of high inclination altimeter missions such as CryoSat and ICESat, it is now feasible to produce Mean Dynamic Topography (MDT) products for the region, which allow a comprehensive investigation of geostrophic currents. However, the accuracy of these products is largely limited by our knowledge of the marine geoid in the Arctic. There are a number of publicly available gravity models commonly used to derive the geoid. These use different combinations of available data (satellite gravimetry, altimetry, laser ranging, and in-situ) and are calculated using different mathematical techniques. However, the effect of these differences on the real world performance of these models when used for oceanographic studies in the Arctic is not well known. Given the unique problems for gravimetry in the region (especially data gaps) and their potential impact on MDT products, it is especially important that the relative performance of these models be assessed We consider the needs of the "end user" satellite oceanographer in the Arctic with respect to gravimetry, and the relationship between the precision of gravity data and the accuracy of a final MDT/current velocity product. Using high-precision aerogravity data collected over 3 years of campaigns by NASA's Operation IceBridge we inter-compare 10 of the leading gravity models and assess their performance in the Arctic. We also use historical data from campaigns flown by the US Naval Research Laboratory (NRL) to demonstrate the impact of gravity errors on MDT products. We describe how gravity models for the region might be improved in the future, in an effort to maximize the level at which Arctic currents may be resolved.
National Oceanic and Atmospheric Administration, Department of Commerce — Visible and Infrared satellite imagery taken from radiometer instruments on SMS (ATS) and GOES satellites in geostationary orbit. These satellites produced...
biogeochemical conditions affect the cycling of climatically important gases viz. carbon dioxide (CO sub(2)), nitrous oxide (N sub(2)O) and methane. Surface waters are normally supersaturated with CO sub(2) in the Arabian Sea and undersaturated in some parts...
The International System of Units (SI) in Oceanography. Report of IAPSO Working Group on Symbols, Units and Nomenclature in Physical Oceanography (SUN). Unesco Technical Papers in Marine Science 45. IAPSO Publication Scientifique No. 32.
United Nations Educational, Scientific, and Cultural Organization, Paris (France). Div. of Marine Sciences.
This report introduces oceanographers to the International System of Units (SI) in physical oceanography. The SI constitutes a universal language, designed to be understood by all scientists. It facilitates their mutual comprehension and exchange of views and results of their work. The first part of the report is devoted to physical quantities,…
's over Brazilian territory. There were 25 platforms when SCD-1 was launched. However this number is growing rapidly to 400 platforms, at first for measurements of water reservoir levels as well as other hydrology applications (The Brazilian Electricity Regulatory Agency - ANEEL is the customer), and for many other different applications such as meteorology, oceanography, environmental monitoring sciences, and people and animal tracking. The clear feeling is that users are discovering a satellite system whose benefits were not previously well understood when launched and being able to propose and come up with different and useful applications. A new field in the country that has a great potential to benefit from this system is agriculture. Per se, this is a very important sector of the Brazilian economy and its international trade. Combining it with space technology may justify the investment of new and low cost dedicated satellites. This paper describes a new proposal for use of the SCD-1,2,CBERS-1 satellite system for precision agriculture. New PCD's would be developed for measurements of chemical content of the soil, such as, for example, Nitrogen and others, beyond humidity and solar incidence. This can lead to a more efficient fertilization, harvesting and even the spray of chemical defensives, with the consequence of environment protection. The PCD's ground network so established, along with the information network already available, combined with the space segment of such a system may, as previously said, be able to justify the investment in low cost satellites with this sole purpose.
Garvani, Sara; Carmisciano, Cosmo; Locritani, Marina; Grossi, Luigi; Mori, Anna; Stroobant, Mascha; Schierano, Erika; De Strobel, Federico; Manzella, Giuseppe; Muzi, Enrico; Leccese, Dario; Sinapi, Luigi; Morellato, Claudio; La Tassa, Hebert; Talamoni, Roberta; Coelho, Emanuel; Nacini, Francesca
Smart, sustainable and inclusive Blue Growth means also knowing past technology and the paths followed by ancients in order to understand and monitor marine environments. In general, history of Science is a matter that is not enough explored and explained or promoted in high schools or university official programmes, and, usually, scientist do not consider it as an important part of their curricula. However, bad or good ideas, abandoned or forgotten beliefs, concepts, opinions, do still have a great potential for inspiring present and future scientists, no matter in which historical period they may have been formulated: they should be always be taken into consideration, critically examined and observed by a very close point of view, not just as part of the intellectual framework of some obsolete 'Cabinet of Curiosities' with limited access except for the chosen few. Moreover, history of Science should be transmitted in a more practical way, with hands-on labs showing the limits and challenges that prior generations of ocean explorers, investigators and seafarers had to face in order to answer to crucial questions as self-orientation in open sea, understanding main currents and waves, predicting meteorological conditions for a safe navigation. Oceanography is a relatively young branch of science, and still needs further approvals and knowledge (National Science Foundation, 2000). The Scientific Dissemination Group (SDG) "La Spezia Gulf of Science" - made up by Research Centres, Schools and Cultural associations located in La Spezia (Liguria, Italy) - has a decadal experience in initiatives aimed at people and groups of people of all ages, who are keen on science or who can be guided in any case to take an interest in scientific matters (Locritani et al., 2015). Amongst the SDG activities, the tight relationship with the Historical Oceanography Society, the Italian Navy and the Naval Technical Museum (that collects a rich heritage of civilization, technology and
A future bilateral SAR program was studied. The requirements supporting a SAR mission posed by science and operations in sea-ice-covered waters, oceanography, renewable resources, and nonrenewable resources are addressed. The instrument, mission, and program parameters were discussed. Research investigations supporting a SAR flight and the subsequent overall mission requirements and tradeoffs are summarized.
Federal Laboratory Consortium — The Bioassay Laboratory is an accredited laboratory capable of conducting standardized and innovative environmental testing in the area of aquatic ecotoxicology. The...
Federal Laboratory Consortium — Naval Academy Hydromechanics LaboratoryThe Naval Academy Hydromechanics Laboratory (NAHL) began operations in Rickover Hall in September 1976. The primary purpose of...
Kamhawi, Hani; Dankanich, John; Martinez, Andres; Petro, Andrew
The Iodine Satellite (iSat) spacecraft will be the first CubeSat to demonstrate high change in velocity from a primary propulsion system by using Hall thruster technology and iodine as a propellant. The mission will demonstrate CubeSat maneuverability, including plane change, altitude change and change in its closest approach to Earth to ensure atmospheric reentry in less than 90 days. The mission is planned for launch in fall 2017. Hall thruster technology is a type of electric propulsion. Electric propulsion uses electricity, typically from solar panels, to accelerate the propellant. Electric propulsion can accelerate propellant to 10 times higher velocities than traditional chemical propulsion systems, which significantly increases fuel efficiency. To enable the success of the propulsion subsystem, iSat will also demonstrate power management and thermal control capabilities well beyond the current state-of-the-art for spacecraft of its size. This technology is a viable primary propulsion system that can be used on small satellites ranging from about 22 pounds (10 kilograms) to more than 1,000 pounds (450 kilograms). iSat's fuel efficiency is ten times greater and its propulsion per volume is 100 times greater than current cold-gas systems and three times better than the same system operating on xenon. iSat's iodine propulsion system consists of a 200 watt (W) Hall thruster, a cathode, a tank to store solid iodine, a power processing unit (PPU) and the feed system to supply the iodine. This propulsion system is based on a 200 W Hall thruster developed by Busek Co. Inc., which was previously flown using xenon as the propellant. Several improvements have been made to the original system to include a compact PPU, targeting greater than 80 percent reduction in mass and volume of conventional PPU designs. The cathode technology is planned to enable heaterless cathode conditioning, significantly increasing total system efficiency. The feed system has been designed to
Wang, Xiao Hua; Cho, Yang-Ki; Guo, Xinyu; Wu, Chau-Ron; Zhou, Junliang
Coastal environments are a key location for transport, commercial, residential and defence infrastructure, and have provided conditions suitable for economic growth. They also fulfil important cultural, recreational and aesthetic needs; have intrinsic ecosystem service values; and provide essential biogeochemical functions such as primary productivity, nutrient cycling and water filtration. The rapid expansion in economic development and anticipated growth of the population in the coastal zones along the Yellow and East China Sea basin has placed this region under intense multiple stresses. Here we aim to: 1) synthesize the new knowledge/science in coastal oceanography since 2010 within the context of the scientific literature published in English; 2) report on a citation analysis that assesses whether new research topics have emerged and integrated over time, indicate the location of modelling and field-based studies; and 3) suggest where the new research should develop for heavily impacted estuaries and coastal seas of East Asia. The conclusions of the synthesis include: 1) China has emerged as a dominant force in the region in producing scientific literature in coastal oceanography, although the area of publications has shifted from its traditional fields such as physical oceanography; 2) there has been an increasing number of publications with cross-disciplinary themes between physical oceanography and other fields of the biological, chemical, and geological disciplines, but vigorous and systematic funding mechanisms are still lacking to ensure the viability of large scale multi-disciplinary teams and projects in order to support trans-disciplinary research and newly emerging fields; 3) coastal oceanography is responding to new challenges, with many papers studying the impacts of human activities on marine environment and ecology, but so far very few studying management and conservation strategies or offering policy solutions.
In April a 64 kbit/s computer communication link was set up between the Joint Institute for Nuclear Research (JINR), Dubna (Russia) and Gran Sasso (Italy) Laboratories via nearby ground satellite stations using the INTELSAT V satellite. Previously the international community of Dubna's experimentalists and theorists (high energy physics, condensed matter physics, low energy nuclear and neutron physics, accelerator and applied nuclear physics) had no effective computer links with scientific centres worldwide
Gomes, P.R.S.; Anjos, R.M.; Macario, K.D.; Santos, G.M.
The first experiment discusses the chronology of prehistoric settlements of the central-south Brazilian coast. In the southern Brazilian coast there is a high density of these shellmounds, dated in general between 6,000 and 2,000 BP. A charcoal sample from a coastal shellmound of Rio de Janeiro State was dated by 14 C-AMS to 7,860±80 years BP. This is an unexpected result that pulls back by some two thousand years the antiquity consensually accepted for the settlement of that region. We performed an experiment concerning the isotopic signature of the local waters of an important Brazilian coastal upwelling, located in Arraial do Cabo, R.J., with applications in the fields of Oceanography and Marine Ecology. We assess the contribution of the wind-driven coastal upwelling of Arraial do Cabo to the local biological production. The variation of the carbon isotopic compositions was investigated in a population of a seaweed. Upwelling events were simulated in the laboratory, in order to study three regimes: total upwelling (SACW), partial upwelling (mixed water) and no-upwelling (TW). Water samples were collected at 70 m depth (SACW) and at 10 m (TW). The seaweed was cultivated during seven days, in controlled conditions, into the three mentioned types of water. The results of 14 C-AMS measurements in the seaweed tissue show a clear indication of difference in the isotopic signature of the water sources, allowing to infer the differences of the water sources. We believe that the present results contribute to opening new perspectives for the use of 14 C as a tracer of the biological production in upwelling areas all over the world. The next reported experiment is on climate at the Amazon region. An increase in the Hg flux is a strong indicator of disturbance in a forest ecosystem related to abrupt changes in the water balance, and its changes reflect changes in the ocean and average regional temperatures. In regions where the geological background of mercury is
Farnsworth, K. L.; House, M.; Hovan, S. A.
A recent workshop sponsored by SERC-On the Cutting Edge brought together science educators from a range of schools across the country to discuss new approaches in teaching oceanography. In discussing student interest in our classes, we were struck by the fact that students are drawn to emotional or controversial topics such as whale hunting and tsunami hazard and that these kinds of topics are a great vehicle for introducing more complex concepts such as wave propagation, ocean upwelling and marine chemistry. Thus, we have developed an approach to introductory oceanography that presents students with real-world issues in the ocean sciences and requires them to explore the science behind them in order to improve overall ocean science literacy among non-majors and majors at 2 and 4 year colleges. We have designed a project-based curriculum built around topics that include, but are not limited to: tsunami hazard, whale migration, ocean fertilization, ocean territorial claims, rapid climate change, the pacific trash patch, overfishing, and ocean acidification. Each case study or project consists of three weeks of class time and is structured around three elements: 1) a media analysis; 2) the role of ocean science in addressing the issue; 3) human impact/response. Content resources range from textbook readings, popular or current print news, documentary film and television, and data available on the world wide web from a range of sources. We employ a variety of formative assessments for each case study in order to monitor student access and understanding of content and include a significant component of in-class student discussion and brainstorming guided by faculty input to develop the case study. Each study culminates in summative assessments ranging from exams to student posters to presentations, depending on the class size and environment. We envision this approach for a range of classroom environments including large group face-to-face instruction as well as hybrid
Caroline L Poli
Full Text Available During breeding, foraging marine birds are under biological, geographic, and temporal constraints. These contraints require foraging birds to efficiently process environmental cues derived from physical habitat features that occur at nested spatial scales. Mesoscale oceanography in particular may change rapidly within and between breeding seasons, and findings from well-studied systems that relate oceanography to seabird foraging may transfer poorly to regions with substantially different oceanographic conditions. Our objective was to examine foraging behavior of a pan-tropical seabird, the Masked Booby (Sula dactylatra, in the understudied Caribbean province, a moderately productive region driven by highly dynamic currents and fronts. We tracked 135 individuals with GPS units during May 2013, November 2013, and December 2014 at a regionally important breeding colony in the southern Gulf of Mexico. We measured foraging behavior using characteristics of foraging trips and used area restricted search as a proxy for foraging events. Among individual attributes, nest stage contributed to differences in foraging behavior whereas sex did not. Birds searched for prey at nested hierarchical scales ranging from 200 m-35 km. Large-scale coastal and shelf-slope fronts shifted position between sampling periods and overlapped geographically with overall foraging locations. At small scales (at the prey patch level, the specific relationship between environmental variables and foraging behavior was highly variable among individuals but general patterns emerged. Sea surface height anomaly and velocity of water were the strongest predictors of area restricted search behavior in random forest models, a finding that is consistent with the characterization of the Gulf of Mexico as an energetic system strongly influenced by currents and eddies. Our data may be combined with tracking efforts in the Caribbean province and across tropical regions to advance
Poli, Caroline L.; Harrison, Autumn-Lynn; Vallarino, Adriana; Gerard, Patrick D.; Jodice, Patrick G.R.
During breeding, foraging marine birds are under biological, geographic, and temporal constraints. These contraints require foraging birds to efficiently process environmental cues derived from physical habitat features that occur at nested spatial scales. Mesoscale oceanography in particular may change rapidly within and between breeding seasons, and findings from well-studied systems that relate oceanography to seabird foraging may transfer poorly to regions with substantially different oceanographic conditions. Our objective was to examine foraging behavior of a pan-tropical seabird, the Masked Booby (Sula dactylatra), in the understudied Caribbean province, a moderately productive region driven by highly dynamic currents and fronts. We tracked 135 individuals with GPS units during May 2013, November 2013, and December 2014 at a regionally important breeding colony in the southern Gulf of Mexico. We measured foraging behavior using characteristics of foraging trips and used area restricted search as a proxy for foraging events. Among individual attributes, nest stage contributed to differences in foraging behavior whereas sex did not. Birds searched for prey at nested hierarchical scales ranging from 200 m—35 km. Large-scale coastal and shelf-slope fronts shifted position between sampling periods and overlapped geographically with overall foraging locations. At small scales (at the prey patch level), the specific relationship between environmental variables and foraging behavior was highly variable among individuals but general patterns emerged. Sea surface height anomaly and velocity of water were the strongest predictors of area restricted search behavior in random forest models, a finding that is consistent with the characterization of the Gulf of Mexico as an energetic system strongly influenced by currents and eddies. Our data may be combined with tracking efforts in the Caribbean province and across tropical regions to advance understanding of seabird
Nuspl, P. P.; Dong, G.
In this decade, communications satellite systems will probably face dramatic challenges from alternative transmission means. To balance and overcome such competition, and to prepare for new requirements, INTELSAT has developed several on-board processing techniques, including Satellite-Switched TDMA (SS-TDMA), Satellite-Switched FDMA (SS-FDMA), several Modulators/Demodulators (Modem), a Multicarrier Multiplexer and Demodulator MCDD), an International Business Service (IBS)/Intermediate Data Rate (IDR) BaseBand Processor (BBP), etc. Some proof-of-concept hardware and software were developed, and tested recently in the INTELSAT Technical Laboratories. These techniques and some test results are discussed.
Merline, W. J.
Discovery and study of small satellites of asteroids or double asteroids can yield valuable information about the intrinsic properties of asteroids themselves and about their history and evolution. Determination of the orbits of these moons can provide precise masses of the primaries, and hence reliable estimates of the fundamental property of bulk density. This reveals much about the composition and structure of the primary and will allow us to make comparisons between, for example, asteroid taxonomic type and our inventory of meteorites. The nature and prevalence of these systems will also give clues as to the collisional environment in which they formed, and have further implications for the role of collisions in shaping our solar system. A decade ago, binary asteroids were more of a theoretical curiosity. In 1993, the Galileo spacecraft allowed the first undeniable detection of an asteroid moon, with the discovery of Dactyl, a small moon of Ida. Since that time, and particularly in the last year, the number of known binaries has risen dramatically. Previously odd-shaped and lobate near-Earth asteroids, observed by radar, have given way to signatures indicating, almost certainly, that at least four NEAs are binary systems. The tell-tale lightcurves of several other NEAs reveal a high likelihood of being double. Indications are that among the NEAs, there may be a binary frequency of several tens of percent. Among the main-belt asteroids, we now know of 6 confirmed binary systems, although their overall frequency is likely to be low, perhaps a few percent. The detections have largely come about because of significant advances in adaptive optics systems on large telescopes, which can now reduce the blurring of the Earth's atmosphere to compete with the spatial resolution of space-based imaging (which itself, via HST, is now contributing valuable observations). Most of these binary systems have similarities, but there are important exceptions. Searches among other
Curtin, Denis J
Trends in Communications Satellites offers a comprehensive look at trends and advances in satellite communications, including experimental ones such as NASA satellites and those jointly developed by France and Germany. The economic aspects of communications satellites are also examined. This book consists of 16 chapters and begins with a discussion on the fundamentals of electrical communications and their application to space communications, including spacecraft, earth stations, and orbit and wavelength utilization. The next section demonstrates how successful commercial satellite communicati
Bruno, B. C.
The ocean sciences suffer from a lack of diversity, particularly among indigenous peoples, despite the fact that indigenous peoples often have deep, cultural knowledge about the marine environment. Nowhere is this inequity more glaring than in Hawaii. Traditional knowledge in marine science enabled Native Hawaiians and Pacific Islanders (NHPI) to become world leaders in transpacific canoe voyaging, aquaculture, and fisheries. Yet today, NHPI are severely underrepresented in the ocean sciences (and in STEM fields in general) at all levels of education and employment. When compared to other ethnic and racial groups in Hawaii, NHPI students as a group have among the poorest educational performance, indicated in part by underrepresentation in college enrolment and pre-college gifted and talented programs, as well as overrepresentation in eligibility for special education and free and reduced lunch programs. The Center of Microbial Oceanography Research and Education (C-MORE), a NSF-funded, multi-institutional Science and Technology Center based at the University of Hawai (UH), is determined to address this inequity. C- MORE is committed to increasing diversity in the ocean sciences, particularly among NHPI, at all levels of education and research. Our approach is to work with existing programs with a track record of increasing diversity among NHPI. We are currently developing culturally relevant materials including educational games for K-12 students, mentorships for high school and community college students, and laboratory and shipboard experiences for teachers and undergraduates in partnership with minority-serving organizations. Some of our main partners are EPSCoR (Experimental Program to Stimulate Competitive Research), Ka `Imi `Ike (an NSF- funded program to recruit and retain NHPI undergraduates in geosciences), Upward Bound (an enrichment program for economically disadvantaged high school students which includes intensive summer courses), the UH Center on
In the Footsteps of Roger Revelle: A STEM Partnership Between Scripps Institution of Oceanography, Office of Naval Research and Middle School Science Students Bringing Next Generation Science Standards into the Classroom through Ocean Science
Brice, D.; Appelgate, B., Jr.; Mauricio, P.
Now in its tenth year, "In the Footsteps of Roger Revelle" (IFRR) is a middle school science education program that draws student interest, scientific content and coherence with Next Generation Science Standards from real-time research at sea in fields of physical science. As a successful collaboration involving Scripps Institution of Oceanography (SIO),Office of Naval Research (ONR), and San Marcos Middle School (SMMS), IFRR brings physical oceanography and related sciences to students at the San Marcos Middle School in real-time from research vessels at sea using SIO's HiSeasNet satellite communication system. With a generous grant from ONR, students are able to tour the SIO Ships and spend a day at sea doing real oceanographic data collection and labs. Through real-time and near-realtime broadcasts and webcasts, students are able to share data with scientists and gain an appreciation for the value of Biogeochemical research in the field as it relates to their classroom studies. Interaction with scientists and researchers as well as crew members gives students insights into not only possible career paths, but the vital importance of cutting edge oceanographic research on our society. With their science teacher on the ship as an education outreach specialist or ashore guiding students in their interactions with selected scientists at sea, students observe shipboard research being carried out live via videoconference, Skype, daily e-mails, interviews, digital whiteboard sessions, and web interaction. Students then research, design, develop, deploy, and field-test their own data-collecting physical oceanography instruments in their classroom. The online interactive curriculum models the Next Generation Science Standards encouraging active inquiry and critical thinking with intellectually stimulating problem- solving, enabling students to gain critical insight and skill while investigating some of the most provocative questions of our time, and seeing scientists as
Schultz, J.F.; Czuchlewski, S.J.; Quick, C.R.
This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project''s primary objective is to determine the technical feasibility of using satellite-based laser wind sensing systems for detailed study of winds, aerosols, and particulates around and downstream of suspected proliferation facilities. Extensive interactions with the relevant operational organization resulted in enthusiastic support and useful guidance with respect to measurement requirements and priorities. Four candidate wind sensing techniques were evaluated, and the incoherent Doppler technique was selected. A small satellite concept design study was completed to identify the technical issues inherent in a proof-of-concept small satellite mission. Use of a Mach-Zehnder interferometer instead of a Fabry-Perot would significantly simplify the optical train and could reduce weight, and possibly power, requirements with no loss of performance. A breadboard Mach-Zehnder interferometer-based system has been built to verify these predictions. Detailed plans were made for resolving other issues through construction and testing of a ground-based lidar system in collaboration with the University of Wisconsin, and through numerical lidar wind data assimilation studies
Imaging satellite systems represent a high capital cost. Optimizing the collection of images is critical for both satisfying customer orders and building a sustainable satellite operations business. We describe the functions of an operational, multivariable, time dynamic optimization system that maximizes the daily collection of satellite images. A graphical user interface allows the operator to quickly see the results of what if adjustments to an image collection plan. Used for both long range planning and daily collection scheduling of Space Imaging's IKONOS satellite, the satellite control and tasking (SCT) software allows collection commands to be altered up to 10 min before upload to the satellite.
Madry, Scott; Camacho-Lara, Sergio
The first edition of this ground breaking reference work was the most comprehensive reference source available about the key aspects of the satellite applications field. This updated second edition covers the technology, the markets, applications and regulations related to satellite telecommunications, broadcasting and networking—including civilian and military systems; precise satellite navigation and timing networks (i.e. GPS and others); remote sensing and meteorological satellite systems. Created under the auspices of the International Space University based in France, this brand new edition is now expanded to cover new innovative small satellite constellations, new commercial launching systems, innovation in military application satellites and their acquisition, updated appendices, a useful glossary and more.
National Oceanic and Atmospheric Administration, Department of Commerce — This Atlas presents primary data on meteorology, oceanography, and hydrobiology from the Barents, Kara, Laptev, and White Seas, which were collected during the...
National Oceanic and Atmospheric Administration, Department of Commerce — This collection comprises data covering meteorology, physical oceanography, transport of water, biogeochemistry, and parameters relevant to the carbon cycle, ocean...
The Frederick National Laboratory for Cancer Research campus is located 50 miles northwest of Washington, D.C., and 50 miles west of Baltimore, Maryland, in Frederick, Maryland. Satellite locations include leased and government facilities extending s
Federal Laboratory Consortium — Purpose:The Photometrics Laboratory provides the capability to measure, analyze and characterize radiometric and photometric properties of light sources and filters,...
Federal Laboratory Consortium — FUNCTION: Enables evaluation and characterization of materials ranging from the ultraviolet to the longwave infrared (LWIR).DESCRIPTION: The Blackroom Laboratory is...
Mapping water use and drought with satellite remote sensing. Martha C. Anderson, Bill Kustas, Feng Gao, Kate Semmens. USDA-Agricultural Research Service Hydrology and Remote Sensing Laboratory, Beltsville, MD. Chris Hain NOAA-NESDIS
Ohmori, Shingo; Isobe, Shunkichi; Takeuchi, Makoto; Naito, Hideyuki
Early in the 21st century, the demand for personal communications using mobile, hand-held, and VSAT terminals will rapidly increase. In a future system, many different types of services should be provided with one-hop connection. The Communications Research Laboratory (CRL) has studied a future advanced mobile satellite communications system using millimeter wave and Ka band. In 1990, CRL started the Communications and Broadcasting Engineering Test Satellite (COMETS) project. The satellite has been developed in conjunction with NASDA and will be launched in 1997. This paper describes the COMETS payload configuration and the experimental system for the advanced mobile communications mission.
Tang, Qunshu; Wang, Caixia; Wang, Dongxiao; Pawlowicz, Rich
Internal solitary waves (ISWs) in the NE South China Sea (SCS) are tidally generated at the Luzon Strait. Their propagation, evolution, and dissipation processes involve numerous issues still poorly understood. Here, a novel method of seismic oceanography capable of capturing oceanic finescale structures is used to study ISWs in the slope region of the NE SCS. Near-simultaneous observations of two ISWs were acquired using seismic and satellite imaging, and water column measurements. The vertical and horizontal length scales of the seismic observed ISWs are around 50 m and 1–2 km, respectively. Wave phase speeds calculated from seismic observations, satellite images, and water column data are consistent with each other. Observed waveforms and vertical velocities also correspond well with those estimated using KdV theory. These results suggest that the seismic method, a new option to oceanographers, can be further applied to resolve other important issues related to ISWs. PMID:24948180
Full Text Available This special issue publishes peer reviewed papers stemming from the International Workshop on Coast and Land applications of satellite altimetry, held 21 -22 July 2006, Beijing, China. This workshop is financially supported by the Chinese Academy of Surveying and Mapping, National Chiao Tung University, Asia GIS and GPS Co., Chung-Hsing Surv. Co., Huanyu Surv. Eng. Cons. Inc., and Real-World Eng. Cons. Inc. Twenty-two papers were submitted to this issue for review, and 16 papers were accepted following an iterative peer-review process. The accepted papers cover subjects on: ICESat coastal altimetry (1, satellite altimetry applications in solid earth sciences (2, hydrology (4, land/coast gravity field modeling (4, and coastal oceanography (5.
Tang, Qunshu; Wang, Caixia; Wang, Dongxiao; Pawlowicz, Rich
Internal solitary waves (ISWs) in the NE South China Sea (SCS) are tidally generated at the Luzon Strait. Their propagation, evolution, and dissipation processes involve numerous issues still poorly understood. Here, a novel method of seismic oceanography capable of capturing oceanic finescale structures is used to study ISWs in the slope region of the NE SCS. Near-simultaneous observations of two ISWs were acquired using seismic and satellite imaging, and water column measurements. The vertical and horizontal length scales of the seismic observed ISWs are around 50 m and 1-2 km, respectively. Wave phase speeds calculated from seismic observations, satellite images, and water column data are consistent with each other. Observed waveforms and vertical velocities also correspond well with those estimated using KdV theory. These results suggest that the seismic method, a new option to oceanographers, can be further applied to resolve other important issues related to ISWs.
Regarding the NPP development in the future, it is needed to make inventory of potential site in the Java Island as well as in the outside Java Island. The NPP site inventory availability is to answer the energy demand challenge. Site screening process should be performed in accordance with the IAEA safety standard regarding the site selection, investigating several aspects related to the NPP safety (exclusion, safety and suitability factor) in the large area to obtain potential site candidates. For the site survey stage of hydrology and oceanography aspects, the analysis are more focused on the tidal phenomena along the north coastline, bathymetry, water resource, and hydrology system in the Banten Province. The method used are secondary data collection, field confirmation and internet searching. The result of the study showed that Tanjung Pujut and Tanjung Pasir are suitable based on the bathymetry and water intake facility consideration. Meanwhile Tanjung Kait and Tanjung Pasir more suitable considering tsunami aspects that may be generated by Krakatau Volcano. (author)
Agostini, Paola; Coppini, Giovanni; Martinelli, Sara; Bonarelli, Roberto; Lecci, Rita; Pinardi, Nadia; Cretì, Sergio; Turrisi, Giuseppe; Ciliberti, Stefania Angela; Federico, Ivan; Mannarini, Gianandrea; Verri, Giorgia; Jansen, Eric; Lusito, Letizia; Macchia, Francesca; Montagna, Fabio; Buonocore, Mauro; Marra, Palmalisa; Tedesco, Luca; Cavallo, Arturo
According to a common definition, ocean literacy is an understanding of the ocean's influence on people and people influence on the ocean. An ocean-literate person is able to make informed and responsible decisions regarding the ocean and its resources. To this aim, this paper presents operational oceanographic tools developed to meet the needs of different users, and activities performed in collaboration with high school students to support new developments of the same tools. Operational oceanography allows to deal with societal challenges such as maritime safety, coastal and marine environment management, climate change assessment and marine resources management. Oceanographic products from the European Copernicus Marine Monitoring Service - CMEMS are transformed and communicated to public and stakeholders through adding-value chains (downstreaming), which consider advanced visualization, usage of multi-channels technological platforms and specific models and algorithms. Sea Situational Awareness is strategically important for management and safety purposes of any marine domain and, in particular, the Mediterranean Sea and its coastal areas. Examples of applications for sea situational awareness and maritime safety are here presented, through user-friendly products available both by web and mobile channels (that already reach more than 100.000 users in the Mediterranean area). Further examples of ocean literacy are web bulletins used to communicate the technical contents and information related to oceanographic forecasts to a wide public. They are the result of a collaboration with high school students, with whom also other activities on improving products visualization and online communication have been performed.
Rostov, I. D.; Moroz, V. V.; Rudykh, N. I.; Rostov, V. I.
The digital atlas on CD ROM includes a set of generalized data on the South China Sea oceanography. The data is presented in the form of spreadsheets, graphics, and text. The atlas contains a brief annotated description of the main physical-geographical characteristics and the particularities of the hydrological regime, water masses, tidal phenomena, and water mass circulation. The atlas is an interactive information-reference system including elements of dynamic data visualization. It contains a body of data on the long-term observations of the temperature and salinity; gridded blocks of the average annual, seasonal, and monthly data at the standard depth horizons; and data on the hydrochemical characteristics and water currents obtained by automatic buoy stations (ABS). A list of existing open access data bases and web sites is given where additional online and archived information on a range of special issues and problems related to regional studies and exploitation is provided. The system allows for fast access to specifically selected online or generalized reference information (via the Internet) and for its imaging.
“Meteorological Satellite Systems” is a primer on weather satellites and their Earth applications. This book reviews historic developments and recent technological advancements in GEO and polar orbiting meteorological satellites. It explores the evolution of these remote sensing technologies and their capabilities to monitor short- and long-term changes in weather patterns in response to climate change. Satellites developed by various countries, such as U.S. meteorological satellites, EUMETSAT, and Russian, Chinese, Japanese and Indian satellite platforms are reviewed. This book also discusses international efforts to coordinate meteorological remote sensing data collection and sharing. This title provides a ready and quick reference for information about meteorological satellites. It serves as a useful tool for a broad audience that includes students, academics, private consultants, engineers, scientists, and teachers.
Geostationary or equatorial synchronous satellites are a daily reminder of our space efforts during the past two decades. The nightly television satellite weather picture, the intercontinental telecommunications of television transmissions and telephone conversations, and the establishrnent of educational programs in remote regions on Earth are constant reminders of the presence of these satellites. As used here, the term 'geo stationary' must be taken loosely because, in the long run, the satellites will not remain 'stationary' with respect to an Earth-fixed reference frame. This results from the fact that these satellites, as is true for all satellites, are incessantly subject to perturbations other than the central-body attraction of the Earth. Among the more predominant pertur bations are: the ellipticity of the Earth's equator, the Sun and Moon, and solar radiation pressure. Higher harmonics of the Earth's potential and tidal effects also influence satellite motion, but they are of second order whe...
NOAA Laboratory for Satellite Altimetry Sea Level Rise Products: Global and regional sea level time series and trend maps for the major ocean basins and marginal seas, based on measurements from satellite radar altimeters, from 1992-12-17 to 2017-08-11 (NCEI Accession 0125535)
National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains global and regional mean sea level time series and trend maps calculated on a continual basis since December 1992 by Laboratory for...
This family portrait shows the smaller satellites of Saturn as viewed by Voyager 2 during its swing through the Saturnian system. The following chart corresponds to this composite photograph (distance from the planet increases from left to right) and lists names, standard numerical designations and approximate dimensions (radii where indicated) in kilometers: 1980S26Outer F-ringshepherd120 X 100 1980S1Leadingco-orbital220 X 160 1980S25TrailingTethys trojanradii: 25 1980S28Outer Ashepherdradii: 20 1980S27Inner F-ringco-orbital145 X 70 1980S3TrailingTethys trojan140 X 100 1980S13LeadingTethys trojanradii: 30 1980S6LeadingDione trojanradii: 30 These images have been scaled to show the satellites in true relative sizes. This set of small objects ranges in size from small asteroidal scales to nearly the size of Saturn's moon Mimas. They are probably fragments of somewhat larger bodies broken up during the bombardment period that followed accretion of the Saturnian system. Scientists believe they may be mostly icy bodies with a mixture of meteorite rock. They are somewhat less reflective than the larger satellites, suggesting that thermal evolution of the larger moons 'cleaned up' their icy surfaces. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif.
Jagannathan, Madhav; Yamashita, Yukiko M
Satellite DNAs are simple tandem repeats that exist at centromeric and pericentromeric regions on eukaryotic chromosomes. Unlike the centromeric satellite DNA that comprises the vast majority of natural centromeres, function(s) for the much more abundant pericentromeric satellite repeats are poorly understood. In fact, the lack of coding potential allied with rapid divergence of repeat sequences across eukaryotes has led to their dismissal as "junk DNA" or "selfish parasites." Although implicated in various biological processes, a conserved function for pericentromeric satellite DNA remains unidentified. We have addressed the role of satellite DNA through studying chromocenters, a cytological aggregation of pericentromeric satellite DNA from multiple chromosomes into DNA-dense nuclear foci. We have shown that multivalent satellite DNA-binding proteins cross-link pericentromeric satellite DNA on chromosomes into chromocenters. Disruption of chromocenters results in the formation of micronuclei, which arise by budding off the nucleus during interphase. We propose a model that satellite DNAs are critical chromosome elements that are recognized by satellite DNA-binding proteins and incorporated into chromocenters. We suggest that chromocenters function to preserve the entire chromosomal complement in a single nucleus, a fundamental and unquestioned feature of eukaryotic genomes. We speculate that the rapid divergence of satellite DNA sequences between closely related species results in discordant chromocenter function and may underlie speciation and hybrid incompatibility. © 2017 Jagannathan and Yamashita; Published by Cold Spring Harbor Laboratory Press.
Hausman, J.; Tsontos, V. M.; Hardman, S. H.
The Physical Oceanography Distributed Active Archive Center (PO.DAAC) is NASA's archive, steward and distributor for physical oceanographic satellite data. Those data are typically organized along the lines of single parameters, such as Sea Surface Temperature, Ocean Winds, Salinity, etc. However there is a need supplement satellite data with in situ and various other remote sensing data to provide higher spatial and temporal sampling and information on physical processes that the satellites are not capable of measuring. This presentation will discuss how PO.DAAC is creating a stewardship and distribution plan that will accommodate satellite, in situ and other remote sensing data that can be used to solve a more integrated approach to data access and utilization along thematic lines in support of science and applications, specifically those posed by Salinity Processes in the Upper Ocean Regional Study (SPURS) and Oceans Melting Greenland (OMG) projects. SPURS used shipboard data, moorings and in situ instruments to investigate changes in salinity and how that information can be used in explaining the water cycle. OMG is studying ice melt in Greenland and how it contributes to changes in sea level through shipboard measurements, airborne and a variety of in situ instruments. PO.DAAC plans on adapting to stewarding and distributing these varieties of data through applications of file format and metadata standards (so data are discoverable and interoperable), extend the internal data system (to allow for better archiving, collection generation and querying of in situ and airborne data) and integration into tools (visualization and data access). We are also working on Virtual Collections with ESDWG, which could provide access to relevant data across DAACs/Agencies along thematic lines. These improvements will improve long-term data management and make it easier for users of various background, regardless if remote sensing or in situ, to discover and use the data.
Pelton, Joseph N.
The status and future of the technologies, numbers and services provided by communications satellites worldwide are explored. The evolution of Intelsat satellites and the associated earth terminals toward high-rate all-digital telephony, data, facsimile, videophone, videoconferencing and DBS capabilities are described. The capabilities, services and usage of the Intersputnik, Eutelsat, Arabsat and Palapa systems are also outlined. Domestic satellite communications by means of the Molniya, ANIK, Olympus, Intelsat and Palapa spacecraft are outlined, noting the fast growth of the market and the growing number of different satellite manufacturers. The technical, economic and service definition issues surrounding DBS systems are discussed, along with presently operating and planned maritime and aeronautical communications and positioning systems. Features of search and rescue and tracking, data, and relay satellite systems are summarized, and services offered or which will be offered by every existing or planned communication satellite worldwide are tabulated.
The benefits of a satellite services system and the basic needs of the Space Transportation System to have improved satellite service capability are identified. Specific required servicing equipment are discussed in terms of their technology development status and their operative functions. Concepts include maneuverable television systems, extravehicular maneuvering unit, orbiter exterior lighting, satellite holding and positioning aid, fluid transfer equipment, end effectors for the remote manipulator system, teleoperator maneuvering system, and hand and power tools.
Federal Laboratory Consortium — This laboratory contains a number of commercial off-the-shelf and in-house software packages allowing for both statistical analysis as well as mathematical modeling...
The foundation of a 'National Laboratory' which would support a Research center in synchrotron radiation applications is proposed. The essential features of such a laboratory differing of others centers in Brazil are presented. (L.C.) [pt
Federal Laboratory Consortium — The Geomechanics Laboratory allows its users to measure rock properties under a wide range of simulated service conditions up to very high pressures and complex load...
Lehahn, Yoav; d'Ovidio, Francesco; Koren, Ilan
The well-lit upper layer of the open ocean is a dynamical environment that hosts approximately half of global primary production. In the remote parts of this environment, distant from the coast and from the seabed, there is no obvious spatially fixed reference frame for describing the dynamics of the microscopic drifting organisms responsible for this immense production of organic matter—the phytoplankton. Thus, a natural perspective for studying phytoplankton dynamics is to follow the trajectories of water parcels in which the organisms are embedded. With the advent of satellite oceanography, this Lagrangian perspective has provided valuable information on different aspects of phytoplankton dynamics, including bloom initiation and termination, spatial distribution patterns, biodiversity, export of carbon to the deep ocean, and, more recently, bottom-up mechanisms that affect the distribution and behavior of higher-trophic-level organisms. Upcoming submesoscale-resolving satellite observations and swarms of autonomous platforms open the way to the integration of vertical dynamics into the Lagrangian view of phytoplankton dynamics.
Lehahn, Yoav; d'Ovidio, Francesco; Koren, Ilan
The well-lit upper layer of the open ocean is a dynamical environment that hosts approximately half of global primary production. In the remote parts of this environment, distant from the coast and from the seabed, there is no obvious spatially fixed reference frame for describing the dynamics of the microscopic drifting organisms responsible for this immense production of organic matter-the phytoplankton. Thus, a natural perspective for studying phytoplankton dynamics is to follow the trajectories of water parcels in which the organisms are embedded. With the advent of satellite oceanography, this Lagrangian perspective has provided valuable information on different aspects of phytoplankton dynamics, including bloom initiation and termination, spatial distribution patterns, biodiversity, export of carbon to the deep ocean, and, more recently, bottom-up mechanisms that affect the distribution and behavior of higher-trophic-level organisms. Upcoming submesoscale-resolving satellite observations and swarms of autonomous platforms open the way to the integration of vertical dynamics into the Lagrangian view of phytoplankton dynamics.
Reynolds, Whitney D.; Doyle, Derek; Arritt, Brandon
Current satellite transportation sensors can provide a binary indication of the acceleration or shock that a satellite has experienced during the shipping process but do little to identify if significant structural change has occurred in the satellite and where it may be located. When a sensor indicates that the satellite has experienced shock during transit, an extensive testing process begins to evaluate the satellite functionality. If errors occur during the functional checkout, extensive physical inspection of the structure follows. In this work an alternate method for inspecting satellites for structural defects after shipping is presented. Electro- Mechanical Impedance measurements are used as an indication of the structural state. In partnership with the Air Force Research Laboratory University Nanosatellite Program, Cornell's CUSat mass model was instrumented with piezoelectric transducers and tested under several structural damage scenarios. A method for detecting and locating changes in the structure using EMI data is presented.
Cable, D. A.; Derocher, W. L., Jr.; Cathcart, J. A.; Keeley, M. G.; Madayev, L.; Nguyen, T. K.; Preese, J. R.
A number of areas of research and laboratory experiments were identified which could lead to development of a cost efficient remote, disable satellite recovery system. Estimates were planned of disabled satellite motion. A concept is defined as a Tumbling Satellite Recovery kit which includes a modular system, composed of a number of subsystem mechanisms that can be readily integrated into varying combinations. This would enable the user to quickly configure a tailored remote, disabled satellite recovery kit to meet a broad spectrum of potential scenarios. The capability was determined of U.S. Earth based satellite tracking facilities to adequately determine the orientation and motion rates of disabled satellites.
Isobe, Shunkichi; Ohmori, Shingo; Hamamoto, Naokazu; Yamamoto, Minoru
Communications Research Laboratory (CRL) studied an advanced mobile satellite communications system using Ka and millimeter-wave bands in the R&D Satellite project. The project started in 1990 and the satellite will be launched in 1997. On-board multi-beam interconnecting is one of basic functions to realize one-hop connection among Very Small Aperture Terminals (VSATs), mobile, and hand-held terminals in future mobile satellite communications system. An Intermediate Frequency (IF) filter bank and regenerative transponder are suitable for this function. The transponder configuration of an advanced mobile communications mission of the R&D Satellite for experiment is shown. High power transmitters of Ka and millimeter-wave bands, a 3x3 IF filter band and Single Channel Per Carrier/Time Division Multiplexing (SCPC/TDM) regenerative MODEMS, which will be boarded on the R&D Satellite, are being developed for the purpose of studying the feasibility of advanced mobile communications system.
Rutherford Appleton Laboratory (RAL), described in this document, supports a wide variety of projects. Each year more than 1000 scientists and engineers visit RAL to use its world-class laser and neutron-scattering facilities. RAL staff design and build instruments which circle the Earth in satellites, increasing our understanding of ozone depletion and global warming, of the life cycles of stars and galaxies and, indeed, of the origin of the Universe itself. They work with their academic colleagues at international laboratories such as European Organization for Nuclear Research (CERN), Geneva, where massive underground machines probe the microstructure of the atomic nucleus. Vastly complex calculations are carried out on the design of anti-cancer drugs, for example, using supercomputers at RAL. (author)
Ariane $loom SAJAC 1 Hughes Satellite Japan 06/94 $150m SAJAC 2 Hughes Satellite Japan -- (spare) $150m SatcomHl GE GE Americom /95 $50m SOLIDARIDAD ...1 Hughes SCT (Mexico) 11/93 Ariane $loom SOLIDARIDAD 2 Hughes SCT (Mexico) /94 $loom Superbird Al Loral Space Com Gp (Jap) 11/92 Ariane $175m
Powell, Marie Clare
Segments of the 1980 National Catholic Educational Association (NCEA) conference were to be telecast nationally by satellite. The author briefly explains the satellite transmission process and advises Catholic educators on how to pick up the broadcast through their local cable television system. (SJL)
Teague, M.J.; Sawyer, D.M.; Vette, J.I.
Considerations related to the early planning for the International Magnetospheric Study (IMS) took into account the desirability of an establishment of specific entities for generating and disseminating coordination information for both retrospective and predictive periods. The organizations established include the IMS/Satellite Situation Center (IMS/SSC) operated by NASA. The activities of the SSC are related to the preparation of reports on predicted and actually achieved satellite positions, the response to inquiries, the compilation of information on satellite experiments, and the issue of periodic status summaries. Attention is given to high-altitude satellite services, other correlative satellite services, non-IMS activities of the SSC, a summary of the SSC request activity, and post-IMS and future activities
Fassbender, Andrea J.; Palevsky, Hilary I.; Martz, Todd R.; Ingalls, Anitra E.; Gledhill, Martha; Fawcett, Sarah E.; Brandes, Jay; Aluwihare, Lihini; Anderson, Robert M.; Bender, Sara; Boyle, Ed; Bronk, Debbie; Buesseler, Ken; Burdige, David J.; Casciotti, Karen; Close, Hilary; Conte, Maureen; Cutter, Greg; Estapa, Meg; Fennel, Katja; Ferron, Sara; Glazer, Brian; Goni, Miguel; Grand, Max; Guay, Chris; Hatta, Mariko; Hayes, Chris; Horner, Tristan; Ingall, Ellery; Johnson, Kenneth G.; Juranek, Laurie; Knapp, Angela; Lam, Phoebe; Luther, George; Matrai, Paty; Nicholson, David; Paytan, Adina; Pellenbarg, Robert; Popendorf, Kim; Reddy, Christopher M.; Ruttenberg, Kathleen; Sabine, Chris; Sansone, Frank; Shaltout, Nayrah; Sikes, Liz; Sundquist, Eric T.; Valentine, David; Wang, Zhao (Aleck); Wilson, Sam; Barrett, Pamela; Behrens, Melanie; Belcher, Anna; Biermann, Lauren; Boiteau, Rene; Clarke, Jennifer; Collins, Jamie; Coppola, Alysha; Ebling, Alina M.; Garcia-Tigreros, Fenix; Goldman, Johanna; Guallart, Elisa F.; Haskell, William; Hurley, Sarah; Janssen, David; Johnson, Winn; Lennhartz, Sinikka; Liu, Shuting; Rahman, Shaily; Ray, Daisy; Sarkar, Amit; Steiner, Zvika; Widner, Brittany; Yang, Bo
The questions that chemical oceanographers prioritize over the coming decades, and the methods we use to address these questions, will define our field's contribution to 21st century science. In recognition of this, the U.S. National Science Foundation and National Oceanic and Atmospheric Administration galvanized a community effort (the Chemical Oceanography MEeting: A BOttom-up Approach to Research Directions, or COME ABOARD) to synthesize bottom-up perspectives on selected areas of research in Chemical Oceanography. Representing only a small subset of the community, COME ABOARD participants did not attempt to identify targeted research directions for the field. Instead, we focused on how best to foster diverse research in Chemical Oceanography, placing emphasis on the following themes: strengthening our core chemical skillset; expanding our tools through collaboration with chemists, engineers, and computer scientists; considering new roles for large programs; enhancing interface research through interdisciplinary collaboration; and expanding ocean literacy by engaging with the public. For each theme, COME ABOARD participants reflected on the present state of Chemical Oceanography, where the community hopes to go and why, and actionable pathways to get there. A unifying concept among the discussions was that dissimilar funding structures and metrics of success may be required to accommodate the various levels of readiness and stages of knowledge development found throughout our community. In addition to the science, participants of the concurrent Dissertations Symposium in Chemical Oceanography (DISCO) XXV, a meeting of recent and forthcoming Ph.D. graduates in Chemical Oceanography, provided perspectives on how our field could show leadership in addressing long-standing diversity and early-career challenges that are pervasive throughout science. Here we summarize the COME ABOARD Meeting discussions, providing a synthesis of reflections and perspectives on the
Villareal, T. A.; Jarmon, L.; Triggs, R.
Shipboard research is a fundamental part of oceanography, but has numerous legal and practical constraints virtually eliminate it as a regular part of large-enrollment programs in marine science. The cost of a properly equipped research vessel alone can prevent student access. While much can be learned by active exploration of archived data by students, the limitations placed on real oceanographic programs by distance, vessel speed, and time are difficult to reproduce in exercises. Pre-cruise planning and collaboration between investigators are likewise a challenge to incorporate. We have used design students in the College of Liberal Arts to construct a oceanographic expedition in Second Life for use in a marine science course (Fall 2009). Second Life is a highly collaborative environment with a variety of tools that allow users to create their own environment and interact with it. Second LIfe is free, highly portable, and inherently amenable to distance or remote teaching. In our application, the research vessel exists as an moving platform with sampling abilities. Software code queries an external MySQL database that contains information from the World Ocean Atlas for the entire ocean, and returns strings of data from standard depths. Students must plan the cruise track to test hypothesis about the ocean, collaborate with other teams to develop the big picture and use standard oceanographic software (Ocean Data Viewer; ODV) to analyze the data. Access to the entire database in ODV then allows comparison to the actual properties and distributions. The effectiveness of this approach is being evaluated by a pre- and post-class surveys and post semester focus group interviews. Similar surveys of the design students that created the environment noted that use of Second Life created a learning experience that was both more immersive and process oriented than traditional college courses. Initial impressions in the marine science class indicate that the strong social
Smith, R. H.; Gerard, T. L.; Johns, E. M.; Lamkin, J. T.
economically important species were recovered at the near-shore sites, south of St. Thomas, St. John, and British Virgin Islands and not on the reef /shelf-break sites as expected. Concurrent Lagrangian drifter trajectories and shipboard ADCP measurements showed a high degree of variability in regional surface water flow. Possible transport pathways as related to the spatial distribution of the larvae collected and the physical oceanography observed will be discussed.
Laine, E. P.; Field, C.
The Campus Compact for New Hampshire (Gordon, 2003) introduced a practical model for designing service-learning exercises or components for new or existing courses. They divided the design and implementation process into eight concrete areas, the “8-Block Model”. Their goal was to demystify the design process of service learning courses by breaking it down into interconnected components. These components include: project design, community partner relations, the problem statement, building community in the classroom, building student capacity, project management, assessment of learning, and reflection and connections. The project design component of the “8-Block Model” asks that the service performed be consistent with the learning goals of the course. For science courses students carry out their work as a way of learning science and the process of science, not solely for the sake of service. Their work supports the goals of a community partner and the community partner poses research problems for the class in a letter on their letterhead. Linking student work to important problems in the community effectively engages students and encourages them to work at more sophisticated levels than usually seen in introductory science classes. Using team-building techniques, the classroom becomes a safe, secure learning environment that encourages sharing and experimentation. Targeted lectures, labs, and demonstrations build the capacity of students to do their research. Behind the scenes project management ensures student success. Learning is assessed using a variety of tools, including graded classroom presentations, poster sessions, and presentations and reports to community partners. Finally, students reflect upon their work and make connections between their research and its importance to the well being of the community. Over the past 10 years, we have used this approach to design and continually modify an introductory oceanography course for majors and non
Ellins, K.; Olson, H.; Pulliam, J.; Schott, M. J.
Science educators working directly with scientists to develop inquiry-based instructional materials in Earth science yield some of the best results. The TEXTEAMS (Texas Teachers Empowered for Achievement in Mathematics and Science) Leadership Training for the Texas high school science course, Geology, Meteorology and Oceanography (GMO) is one example of a successful program that provides high-quality training to master teachers using geophysical data collected by scientists at The University of Texas Institute for Geophysics (UTIG). TEXTEAMS is a certification program of professional development and leadership training sponsored by the National Science Foundation that is part of the Texas Statewide Systemic Initiative. UTIG scientists teamed with science educators at the Charles A. Dana Center for Mathematics and Science Education at UT and the Texas Education Agency to develop inquiry-based instructional materials for eight GMO modules. Our learning activities help students and teachers understand how Earth scientists interpret the natural world and test their hypotheses, and provide opportunities for the use of technology in classroom science learning; they are aligned with national and state teaching standards. Examples of TEXTEAMS GMO learning activities that use geophysical data. 1. Neotectonics: radiocarbon dates and elevation above current sea level of raised coral reefs in the New Georgia Islands are used to calculate rates of tectonic uplift and as a basis for the development of a conceptual model to explain the pattern of uplift that emerges from the data. 2. Large Igneous Provinces:geophysical logging data collected on ODP Leg 183 (Kerguelen Plateau) are analyzed to identify the transition from sediment to basement rock. 3. The Search for Black Gold: petroleum exploration requires the integration of geology, geophysics, petrophysics and geochemistry. Knowledge gained in previous GMO modules is combined with fundamental knowledge about economics to
Herrera, Joshua M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
This report is an analysis of the means of egress and life safety requirements for the laboratory building. The building is located at Sandia National Laboratories (SNL) in Albuquerque, NM. The report includes a prescriptive-based analysis as well as a performance-based analysis. Following the analysis are appendices which contain maps of the laboratory building used throughout the analysis. The top of all the maps is assumed to be north.
Federal Laboratory Consortium — Purpose: To conduct fundamental studies of highway materials aimed at understanding both failure mechanisms and superior performance. New standard test methods are...
Federal Laboratory Consortium — The NWFSC conducts critical fisheries science research at its headquarters in Seattle, WA and at five research stations throughout Washington and Oregon. The unique...
Federal Laboratory Consortium — The Dynamics Lab replicates vibration environments for every Navy platform. Testing performed includes: Flight Clearance, Component Improvement, Qualification, Life...
Federal Laboratory Consortium — This facility provides testing stations for computer-based assessment of cognitive and behavioral Warfighter performance. This 500 square foot configurable space can...
Federal Laboratory Consortium — FUNCTION: Evaluates and improves the operational effectiveness of existing and emerging electronic warfare systems. By analyzing and visualizing simulation results...
Federal Laboratory Consortium — The Analytical Labspecializes in Oil and Hydraulic Fluid Analysis, Identification of Unknown Materials, Engineering Investigations, Qualification Testing (to support...
Federal Laboratory Consortium — The Propulsion Lab simulates field test conditions in a controlled environment, using standardized or customized test procedures. The Propulsion Lab's 11 cells can...
Federal responsibility for oil and gas development on the U.S. outer continental shelf (OCS) resides with the Minerals Management Service (MMS) of the U.S. Department of the Interior (DOI). The DOI's Environmental Studies Program (ESP) is the program through which MMS conducts environmental studies on the OCS and collects information to prepare environmental impact statements (EISs). It appeared to MMS in 1986 that the time was ripe to assess the status of the present program and to explore the needs for future studies. MMS requested an evaluation of the adequacy and applicability of ESP studies, a review of the general state of knowledge in the appropriate disciplines, and recommendations for future studies. Three panels were established, one of which, the Physical Oceanography Panel, investigated the physical oceanographic aspects of the ESP, the subject of the report, which is the first of three in a series. In reviewing the ESP's physical oceanography program, the panel evaluated the quality and relevance of studies carried out in waters under federal control, which extend from the limits of state jurisdictions (3-12 miles offshore) and include the central and outer continental shelf waters and the continental slope
Constantin, A., E-mail: email@example.com [Department of Mathematics, King' s College London, Strand, London WC2R 2LS (United Kingdom); Faculty of Mathematics, University of Vienna, Oskar-Morgenstern-Platz 1, 1090 Vienna (Austria); Johnson, R.S., E-mail: firstname.lastname@example.org [School of Mathematics & Statistics, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)
Highlights: • Systematic theoretical methods in studies of equatorial ocean dynamics. • Linear wave-current interactions in stratified flows. • Exact solutions – Kelvin waves, azimuthal non-uniform currents. • Three-dimensional nonlinear currents. • Hamiltonian formulation for the governing equations and for structure-preserving/enhancing approximations. - Abstract: This essay is a commentary on the pivotal role of systematic theoretical methods in physical oceanography. At some level, there will always be a conflict between theory and experiment/data collection: Which is pre-eminent? Which should come first? This issue appears to be particularly marked in physical oceanography, to the extreme detriment of the development of the subject. It is our contention that the classical theory of fluids, coupled with methods from the theory of differential equations, can play a significant role in carrying the subject, and our understanding, forward. We outline the philosophy behind a systematic theoretical approach, highlighting some aspects of equatorial ocean dynamics where these methods have already been successful, paving the way for much more in the future and leading, we expect, to the better understanding of this and many other types of ocean flow. We believe that the ideas described here promise to reveal a rich and beautiful dynamical structure.
Sikorski, J. J.; Briggs, B. R.
The ocean is essential for life on our planet. It covers 71% of the Earth's surface, is the source of the water we drink, the air we breathe, and the food we eat. Yet, the exponential growth in human population is putting the ocean and thus life on our planet at risk. However, based on student evaluations from our introductory oceanography course it is clear that our students have deficiencies in ocean literacy that impact their ability to recognize that the ocean and humans are inextricably connected. Furthermore, life present in deep subsurface marine environments is also interconnected to the study of the ocean, yet the deep biosphere is not typically covered in undergraduate oceanography courses. In an effort to improve student ocean literacy we developed an instructional module on the deep biosphere focused on gas hydrate deposits. Specifically, our module utilizes Google Earth and cutting edge research about microbial life in the ocean to support three inquiry-based activities that each explore different facets of gas hydrates (i.e. environmental controls, biologic controls, and societal implications). The relevant nature of the proposed module also makes it possible for instructors of introductory geology courses to modify module components to discuss related topics, such as climate, energy, and geologic hazards. This work, which will be available online as a free download, is a solid contribution toward increasing the available teaching resources focused on the deep biosphere for geoscience educators.
Ponte, Rui M.; Ray, Richard D.
Global pressure data are often needed for processing or interpreting modern geodetic and oceanographic measurements. The most common source of these data is the analysis or reanalysis products of various meteorological centers. Tidal signals in these products can be problematic for several reasons, including potentially aliased sampling of the semidiurnal solar tide as well as the presence of various modeling or timing errors. Building on the work of Van den Dool and colleagues, we lay out a strategy for handling atmospheric tides in (re)analysis data. The procedure also offers a method to account for ocean loading corrections in satellite altimeter data that are consistent with standard ocean-tide corrections. The proposed strategy has immediate application to the on-going Jason-1 and GRACE satellite missions.
Jacques, Peter J.
The decline of top oceanic predators (TOPs), such as great sharks, and worldwide erosion of the marine food web is among the most important functional changes in marine systems. Yet, even though human pressures on sharks are one of the most important factors in the collapse of TOPs, the social science of shark fishing has not kept pace with the biophysical science. Such a gap highlights the need for a marine social science, and this paper uses the case of sharks to illustrate some advances that a coherent marine social science community could bring to science and sustainability, and calls for the development of this new field. Social oceanography is proposed as a “discursive space” that will allow multiple social science and humanities disciplines to holistically study and bring insight to a diverse but essential community. Such a community will not provide answers for the physical sciences, but it will add a new understanding of the contingencies that riddle social behavior that ultimately interact with marine systems. Such a field should reflect the broad and diverse approaches, epistemologies, philosophies of science and foci that are in the human disciplines themselves. Social oceanography would complete the triumvirate of biological and physical oceanography where human systems profoundly impact these other areas. This paper tests the theory that institutional rules are contingent on social priorities and paradigms. I used content analysis of all available (1995-2006) State of the World Fisheries and Aquaculture (SOFIA) reports from the United Nations Food and Agricultural Organization (FAO) to measure the symbolic behavior-i.e., what they say-as an indication of the value of sharks in world fisheries. Similar tests were also performed for marine journals and the Convention on Migratory Species of Wild Animals to corroborate these findings. Then, I present an institutional analysis of all international capacity building and regulatory institutions as they
The TOPEX/POSEIDON space mission, sponsored by NASA and France's space agency, the Centre National d'Etudes Spatiales (CNES), will give new observations of the Earth from space to gain a quantitative understanding of the role of ocean currents in climate change. Rising atmospheric concentrations of carbon dioxide and other 'greenhouse gases' produced as a result of human activities could generate a global warming, followed by an associated rise in sea level. The satellite will use radar altimetry to measure sea-surface height and will be tracked by three independent systems to yield accurate topographic maps over the dimensions of entire ocean basins. The satellite data, together with the Tropical Ocean and Global Atmosphere (TOGA) program and the World Ocean Circulation Experiment (WOCE) measurements, will be analyzed by an international scientific team. By merging the satellite observations with TOGA and WOCE findings, the scientists will establish the extensive data base needed for the quantitative description and computer modeling of ocean circulation. The ocean models will eventually be coupled with atmospheric models to lay the foundation for predictions of global climate change.
Mccarter, J. W.
A method is presented for computing the probability of a collision between a particular artificial earth satellite and any one of the total population of earth satellites. The collision hazard incurred by the proposed modular Space Station is assessed using the technique presented. The results of a parametric study to determine what type of satellite orbits produce the greatest contribution to the total collision probability are presented. Collision probability for the Space Station is given as a function of Space Station altitude and inclination. Collision probability was also parameterized over miss distance and mission duration.
Leprovost, Christian; Mazzega, P.; Vincent, P.
Ocean tides must be considered in many scientific disciplines: astronomy, oceanography, geodesy, geophysics, meteorology, and space technologies. Progress in each of these disciplines leads to the need for greater knowledge and more precise predictions of the ocean tide contribution. This is particularly true of satellite altimetry. On one side, the present and future satellite altimetry missions provide and will supply new data that will contribute to the improvement of the present ocean tide solutions. On the other side, tidal corrections included in the Geophysical Data Records must be determined with the maximum possible accuracy. The valuable results obtained with satellite altimeter data thus far have not been penalized by the insufficiencies of the present ocean tide predictions included in the geophysical data records (GDR's) because the oceanic processes investigated have shorter wavelengths than the error field of the tidal predictions, so that the residual errors of the tidal corrections are absorbed in the empirical tilt and bias corrections of the satellite orbit. For future applications to large-scale oceanic phenomena, however, it will no longer be possible to ignore these insufficiencies.
Kesten, Philip R.
The best summary of my work at NASA is expressed in the following abstract, submitted the Division for Planetary Science of the American Astronomical Society and to be presented at the annual meeting in Madison in October. We report photometric measurements of Uranian satellites Miranda, Ariel, Umbriel and Titania (10.4 Aug. 1995), and Neptune's satellite Triton (21.2 Sept. 1995) with the infrared camera (IRCAM) and standard J (1.13 - 1.42 microns), H (1.53 - 1.81 microns), and K (2.00 - 2.41 microns) filters at the 3.8-m UKIRT telescope on Mauna Kea. The individual images frames are 256 x 256 pixels with a platescale of .286 arcsec/pixel, resulting in a 1.22 arc min field of view. This summer brought the IR photometry measurements nearly to a close. As indicated by the abstract above, I will present this work at the annual DPS meeting in October. In anticipation of the opening of the new Carl Sagan Laboratory for Cosmochemisty, of which I will be a participating member, I also devoted a considerable fraction of the summer to learning the biochemistry which underlies the experiments to be conducted. To put the end of the summary close to the beginning, it was a most productive summer.
Chern, Jeng-Shing; Ling, Jer; Weng, Shui-Lin
FORMOSAT-2 is Taiwan's first remote sensing satellite (RSS). It was launched on 20 May 2004 with five-year mission life and a very unique mission orbit at 891 km altitude. This orbit gives FORMOSAT-2 the daily revisit feature and the capability of imaging the Arctic and Antarctic regions due to the high enough altitude. For more than three years, FORMOSAT-2 has performed outstanding jobs and its global effectiveness is evidenced in many fields such as public education in Taiwan, Earth science and ecological niche research, preservation of the world heritages, contribution to the International Charter: space and major disasters, observation of suspected North Korea and Iranian nuclear facilities, and scientific observation of the atmospheric transient luminous events (TLEs). In order to continue the provision of earth observation images from space, the National Space Organization (NSPO) of Taiwan started to work on the second RSS from 2005. This second RSS will also be Taiwan's first indigenous satellite. Both the bus platform and remote sensing instrument (RSI) shall be designed and manufactured by NSPO and the Instrument Technology Research Center (ITRC) under the supervision of the National Applied Research Laboratories (NARL). Its onboard computer (OBC) shall use Taiwan's indigenous LEON-3 central processing unit (CPU). In order to achieve cost effective design, the commercial off the shelf (COTS) components shall be widely used. NSPO shall impose the up-screening/qualification and validation/verification processes to ensure their normal functions for proper operations in the severe space environments.
Madry, Scott; Camacho-Lara, Sergio
Top space experts from around the world have collaborated to produce this comprehensive, authoritative, and clearly illustrated reference guide to the fast growing, multi-billion dollar field of satellite applications and space communications. This handbook, done under the auspices of the International Space University based in France, addresses not only system technologies but also examines market dynamics, technical standards and regulatory constraints. The handbook is a completely multi-disciplinary reference book that covers, in an in-depth fashion, the fields of satellite telecommunications, Earth observation, remote sensing, satellite navigation, geographical information systems, and geosynchronous meteorological systems. It covers current practices and designs as well as advanced concepts and future systems. It provides a comparative analysis of the common technologies and design elements for satellite application bus structures, thermal controls, power systems, stabilization techniques, telemetry, com...
A discussion of the Federal Communications Commission's new policy on domestic satellites in light of our 1) military and economic history; 2) corporate interests; 3) citizen surveillance; and 4) media control. (HB)
First page Back Continue Last page Overview Graphics. SATELLITE CONSTELLATION DESIGN PARAMETER. 1. ORBIT CHARACTERISTICS. ORBITAL HEIGHT >= 20,000 KM. LONGER VISIBILITY; ORBITAL PERIOD. PERTURBATIONS(MINIMUM). SOLAR RADIATION PRESSURE (IMPACTS ECCENTRICITY); LUNI ...
Colton, Marie C.; Powell, Alfred M.; Jordan, Gretchen; Mote, Jonathon; Hage, Jerald; Frank, Donald
The NESDIS Center for Satellite Applications and Research (STAR), formerly ORA, Office of Research and Applications, consists of three research and applications divisions that encompass satellite meteorology, oceanography, climatology, and cooperative research with academic institutions. With such a wide background of talent, and a charter to develop operational algorithms and applications, STAR scientists develop satellite-derived land, ice, ocean, and atmospheric environmental data products in support of all of NOAA"s mission goals. In addition, in close association with the Joint Center for Satellite Data Assimilation, STAR scientists actively work with the numerical modeling communities of NOAA, NASA, and DOD to support the development of new methods for assimilation of satellite data. In this new era of observations from many new satellite instruments, STAR aims to effectively integrate these data into multi-platform data products for utilization by the forecast and applications communities. Much of our work is conducted in close partnerships with other agencies, academic institutes, and industry. In order to support the nearly 400 current satellite-derived products for various users on a routine basis from our sister operations office, and to evolve to future systems requires an ongoing strategic planning approach that maps research and development activities from NOAA goals to user requirements. Since R&D accomplishments are not necessarily amenable to precise schedules, appropriate motivators and measures of scientific progress must be developed to assure that the product development cycle remains aligned with the other engineering segments of a satellite program. This article presents the status and results of this comprehensive effort to chart a course from the present set of operational satellites to the future.
Bergsrud, Corey Alexis Marvin
Space solar power satellite (SSPS) systems is the concept of placing large satellite into geostationary Earth orbit (GEO) to harvest and convert massive amounts of solar energy into microwave energy, and to transmit the microwaves to a rectifying antenna (rectenna) array on Earth. The rectenna array captures and converts the microwave power into usable power that is injected into the terrestrial electric grid for use. This work approached the microwave power beam as an additional source of power (with solar) for lower orbiting satellites. Assuming the concept of retrodirectivity, a GEO-SSPS antenna array system tracks and delivers microwave power to lower orbiting satellites. The lower orbiting satellites are equipped with a stacked photovoltaic (PV)/rectenna array hybrid power generation unit (HPGU) in order to harvest solar and/or microwave energy for on-board use during orbit. The area, and mass of the PV array part of the HPGU was reduced at about 32% beginning-of-life power in order to achieve the spacecraft power requirements. The HPGU proved to offer a mass decrease in the PGU, and an increase in mission life due to longer living component life of the rectenna array. Moreover, greater mission flexibility is achieved through a track and power delivery concept. To validate the potential advantages offered by a HPGU, a mission concept was presented that utilizes modern small satellites as technology demonstrators. During launch, a smaller power receiving "daughter" satellite sits inside a larger power transmitting "mother" satellite. Once separated from the launch vehicle the daughter satellite is ejected away from the mother satellite, and each satellite deploys its respective power transmitting or power receiving hardware's for experimentation. The concept of close proximity mission operations between the satellites is considered. To validate the technology of the space rectenna array part of the HPGU, six milestones were completed in the design. The first
Reed, D. L.
The results of assessing student learning in an online oceanography class offered over the past five years are compiled to reveal several general trends. In order to understand the context of these trends, it is important to first note that SJSU has a two-tiered general education program consisting of a category of core courses for frosh and sophomores and an advanced category for juniors and seniors, most of whom are community college transfers. The course described in this study is in the latter category and therefore composed largely of seniors. Enrollments in the course have exploded from 6 students in a pilot section offered during the 1998 fall semester to over 170 students in the summer semester of 2002. The course is now offered in both semesters of the academic year with four sections offered during 2002 summer session as part of a system-wide conversion to year-round operation. No other course, be it classroom, hybrid or online, in the general education category has experienced the level of student demand as this online course. All sections of the online course reach enrollment limits in the first days of registration with an equal or greater number of students turned away each semester. More female, students of color, returning students and K-12 in-service teachers enroll in the online sections than in the equivalent classroom sections of the course. Students enroll in the online section for the convenience of self-paced learning since attending a classroom section is not a viable option. Enrollments in concurrent classroom sections have not been negatively impacted by the addition of online sections. Enrollment attrition is higher in the first few days of the online course, but similar to that experienced in the classroom sections, once the class is underway. However, student requests for incompletes tend to be somewhat higher in the online course, especially during the summer offerings. Learning outcomes are reviewed at the beginning of the course and
Manzano Muñoz, Fernando; Pouliquen, Sylvie; Petit de la Villeon, Loic; Carval, Thierry; Loubrieu, Thomas; Wedhe, Henning; Sjur Ringheim, Lid; Hammarklint, Thomas; Tamm, Susanne; De Alfonso, Marta; Perivoliotis, Leonidas; Chalkiopoulos, Antonis; Marinova, Veselka; Tintore, Joaquin; Troupin, Charles
Copernicus, previously known as GMES (Global Monitoring for Environment and Security), is the European Programme for the establishment of a European capacity for Earth Observation and Monitoring. Copernicus aims to provide a sustainable service for Ocean Monitoring and Forecasting validated and commissioned by users. From May 2015, the Copernicus Marine Environment Monitoring Service (CMEMS) is working on an operational mode through a contract with services engagement (result is regular data provision). Within CMEMS, the In Situ Thematic Assembly Centre (INSTAC) distributed service integrates in situ data from different sources for operational oceanography needs. CMEMS INSTAC is collecting and carrying out quality control in a homogeneous manner on data from providers outside Copernicus (national and international networks), to fit the needs of internal and external users. CMEMS INSTAC has been organized in 7 regional Dissemination Units (DUs) to rely on the EuroGOOS ROOSes. Each DU aggregates data and metadata provided by a series of Production Units (PUs) acting as an interface for providers. Homogeneity and standardization are key features to ensure coherent and efficient service. All DUs provide data in the OceanSITES NetCDF format 1.2 (based on NetCDF 3.6), which is CF compliant, relies on SeaDataNet vocabularies and is able to handle profile and time-series measurements. All the products, both near real-time (NRT) and multi-year (REP), are available online for every CMEMS registered user through an FTP service. On top of the FTP service, INSTAC products are available through Oceanotron, an open-source data server dedicated to marine observations dissemination. It provides services such as aggregation on spatio-temporal coordinates and observed parameters, and subsetting on observed parameters and metadata. The accuracy of the data is checked on various levels. Quality control procedures are applied for the validity of the data and correctness tests for the
Intelligent Space Systems Laboratory, The University of Tokyo (ISSL) and National Astronomical Observatory of Japan (NAO) have been developing a small infrared astrometry satellite named “Nano-JASMINE”. The satellite size is about 50cm cubic and 20kg, which plays a pre-cursor role of JASMINE Project which is programmed by NAO and JAXA. In addition, since there has been only one astrometry satellite HIPPARCOS by ESA in the past, Nano-JASMINE is also expected to achieve certain scientific results in the field of astrometry. In this project, ISSL aims to develop new advanced small satellite bus system whose performance is comparable to that of 100-500kg sized satellites, including attitude stability of 1 arc-second and thermal stability of the mission subsystem of 1 mK. This paper overviews the Nano-JASMINE bus system with emphasis on attitude and thermal control systems.
Shamma, Mohammed A.
This presentation is an overview on Satellite Communication for the Aeronautical Telecommunication Management (ATM) research. Satellite Communications are being considered by the FAA and NASA as a possible alternative to the present and future ground systems supporting Air Traffic Communications. The international Civil Aviation Organization (ICAO) have in place Standards and Recommended Practices (SARPS) for the Aeronautical Mobile Satellite Services (AMSS) which is mainly derived from the pre-existing Inmarsat service that has been in service since the 1980s. The Working Group A of the Aeronautical Mobile Communication Panel of ICAO has also been investigating SARPS for what is called the Next Generation Satellite Service (NGSS) which conforms less to the Inmarsat based architecture and explores wider options in terms of satellite architectures. Several designs are being proposed by Firms such as Boeing, ESA, NASA that are geared toward full or secondary usage of satellite communications for ATM. Satellite communications for ATM can serve several purposes ranging from primary usage where ground services would play a minimal backup role, to an integrated solution where it will be used to cover services, or areas that are less likely to be supported by the proposed and existing ground infrastructure. Such Integrated roles can include usage of satellite communications for oceanic and remote land areas for example. It also can include relieving the capacity of the ground network by providing broadcast based services of Traffic Information Services messages (TIS-B), or Flight Information Services (FIS-B) which can take a significant portion of the ground system capacity. Additionally, satellite communication can play a backup role to support any needs for ground replacement, or additional needed capacity even after the new digital systems are in place. The additional bandwidth that can be provided via satellite communications can also open the door for many new
... Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & ... What are lab tests? Laboratory tests are medical devices that are intended for use on samples of blood, urine, or other tissues ...
Federal Laboratory Consortium — FUNCTION: Provides an environment and facilities for auditory display research. A primary focus is the performance use of binaurally rendered 3D sound in conjunction...
Ephraim, D.C.; Pednekar, A.R.
A target laboratory to make stripper foils for the accelerator and various targets for use in the experiments is set up in the pelletron accelerator facility. The facilities available in the laboratory are: (1) D.C. glow discharge setup, (2) carbon arc set up, and (3) vacuum evaporation set up (resistance heating), electron beam source, rolling mill - all for target preparation. They are described. Centrifugal deposition technique is used for target preparation. (author). 3 figs
Federal Laboratory Consortium — The Semiconductor Electrical Measurements Laboratory is a research laboratory which complements the Optical Measurements Laboratory. The laboratory provides for Hall...
Schnetzler, C. C.
The literature associated with the Magsat mission has evaluated the capabilities and limitations of satellite measurements of the earth's crustal magnetic field, and demonstrated that there exists a 300-3000 km magnetic field, related to major features in the earth's crust, which is primarily caused by induction. Due to its scale and sensitivity, satellite data have been useful in the development of models for such large crustal features as subduction zones, submarine platforms, continental accretion boundaries, and rifts. Attention is presently given to the lack of agreement between laboratory and satellite estimates of lower crustal magnetization.
D. K. Lee
Full Text Available Low resolution spectroscopic observations of geo-stationary satellites over the Korean peninsula have been carried out at the KyungHee Optical Satellite Observing Facility (KOSOF with a 40cm telescope. We have observed 9 telecommunication satellites and 1 weather satellite of 6 countries. The obtained spectral data showed that satellites could be classified and grouped with similar basic spectral feature. We divided the 10 satellites into 4 groups based on spectral slop and reflectance. It is suggested that the material types of the satellites can be determined through spectral comparisons with the ground laboratory data. We will continuously observe additional geo-stationary satellites for the accurate classification of spectral features.
Park, Changbom; Hwang, Ho Seong; Park, Hyunbae; Lee, Jong Chul
The hierarchical galaxy formation scenario in the Cold Dark Matter cosmology with a non-vanishing cosmological constant Λ and geometrically flat space (ΛCDM) has been very successful in explaining the large-scale distribution of galaxies. However, there have been claims that ΛCDM over-predicts the number of satellite galaxies associated with massive galaxies compared with observations—the missing satellite galaxy problem1-3. Isolated groups of galaxies hosted by passively evolving massive early-type galaxies are ideal laboratories for identifying the missing physics in the current theory4-11. Here, we report—based on a deep spectroscopic survey—that isolated massive and passive early-type galaxies without any signs of recent wet mergers or accretion episodes have almost no satellite galaxies fainter than the r-band absolute magnitude of about Mr = -14. If only early-type satellites are used, the cutoff is at the somewhat brighter magnitude of about Mr = -15. Such a cutoff has not been found in other nearby satellite galaxy systems hosted by late-type galaxies or those with merger features. Various physical properties of satellites depend strongly on the host-centric distance. Our observations indicate that the satellite galaxy luminosity function is largely determined by the interaction of satellites with the environment provided by their host.
In January 1994, the two geostationary satellites known as Anik-E1 and Anik-E2, operated by Telesat Canada, failed one after the other within 9 hours, leaving many northern Canadian communities without television and data services. The outage, which shut down much of the country's broadcast television for hours and cost Telesat Canada more than $15 million, generated significant media attention. Lam et al. used publicly available records to revisit the event; they looked at failure details, media coverage, recovery effort, and cost. They also used satellite and ground data to determine the precise causes of those satellite failures. The researchers traced the entire space weather event from conditions on the Sun through the interplanetary medium to the particle environment in geostationary orbit.
The developmental history, current status, and future plans of the ESA satellite-communications programs are discussed in a general survey and illustrated with network diagrams and maps. Consideration is given to the parallel development of national and European direct-broadcast systems and telecommunications networks, the position of the European space and electronics industries in the growing world market, the impact of technological improvements (both in satellite systems and in ground-based networks), and the technological and commercial advantages of integrated space-terrestrial networks. The needs for a European definition of the precise national and international roles of satellite communications, for maximum speed in implementing such decisions (before the technology becomes obsolete), and for increased cooperation and standardization to assure European equipment manufacturers a reasonable share of the market are stressed.
Flournoy, Don M
Communication satellites are a $144 billion industry. Is there any space-based industry that could possibly beat that market? 'Solar Power Satellites' shows why and how the space satellite industry will soon begin expanding its market from relaying signals to Earth to generating energy in space and delivering it to the ground as electricity. In all industrialized nations, energy demand is growing exponentially. In the developing world, the need for energy is as basic as food and water. The Sun's energy is available everywhere, and it is non-polluting. As business plans demonstrate its technical feasibility, commercial potential, and environmental acceptability, every country on Earth will look to space for the power it needs.
This report from the Dutch Ministry of Health is an advisory document concerned with isotope laboratories in hospitals, in connection with the Dutch laws for hospitals. It discusses which hospitals should have isotope laboratories and concludes that as many hospitals as possible should have small laboratories so that emergency cases can be dealt with. It divides the Netherlands into regions and suggests which hospitals should have these facilities. The questions of how big each lab. is to be, what equipment each has, how each lab. is organised, what therapeutic and diagnostic work should be carried out by each, etc. are discussed. The answers are provided by reports from working groups for in vivo diagnostics, in vitro diagnostics, therapy, and safety and their results form the criteria for the licences of isotope labs. The results of a questionnaire for isotope labs. already in the Netherlands are presented, and their activities outlined. (C.F.)
Simakov, M. B.
At the beginning of 2004 the total number of discovered planets near other stars was 119 All of them are massive giants and met practically in all orbits In a habitable zone from 0 8 up to 1 1 AU at less 11 planets has been found starting with HD 134987 and up to HD 4203 It would be naive to suppose existence of life in unique known to us amino-nucleic acid form on the gas-liquid giant planets Nevertheless conditions for onset and evolutions of life can be realized on hypothetical satellites extrasolar planets All giant planets of the Solar system have a big number of satellites 61 of Jupiter 52 of Saturn known in 2003 A small part of them consist very large bodies quite comparable to planets of terrestrial type but including very significant share of water ice Some from them have an atmosphere E g the mass of a column of the Titan s atmosphere exceeds 15 times the mass of the Earth atmosphere column Formation or capture of satellites is a natural phenomenon and satellite systems definitely should exist at extrasolar planets A hypothetical satellite of the planet HD 28185 with a dense enough atmosphere and hydrosphere could have biosphere of terrestrial type within the limits of our notion about an origin of terrestrial biosphere As an example we can see on Titan the largest satellite of Saturn which has a dense nitrogen atmosphere and a large quantity of liquid water under ice cover and so has a great exobiological significance The most recent models of the Titan s interior lead to the conclusion that a substantial liquid layer
Griffin, D.; Cresswell, G.; Badcock, K.; Cahill, M.; Rathbone, C.; Turner, P.
Satellite altimeter measurements of sea level have proven to be far more accurate, and useful, than was hope for when the missions were designed, especially when data from several instruments are combines. In the regard, the experimental missions (ERS1 and 2, Topex/Poseidon, Jason-1 and GFO) have all been a resounding success. Why then, are there not plans already in place to continue and improve on the recent missions? One reason is surely that end-user uptake of the mission products has not yet convincingly justified the costs of future missions. At CSIRO we sought to maximise the awareness, amongst all marine sectors, that mapping ocean currents with sufficient accuracy and detail for operational use is indeed possible, so that the societal benefits of the system would become clear as quickly as possible. We did this using a well know marketing too - sport.
Leick, Alfred; Tatarnikov, Dmitry
THE MOST COMPREHENSIVE, UP-TO-DATE GUIDE ON GPS TECHNOLOGY FOR SURVEYING Three previous editions have established GPS Satellite Surveying as the definitive industry reference. Now fully updated and expanded to reflect the newest developments in the field, this Fourth Edition features cutting-edge information on GNSS antennas, precise point positioning, real-time relative positioning, lattice reduction, and much more. Expert authors examine additional tools and applications, offering complete coverage of geodetic surveying using satellite technologies. The past decade has seen a major evolut
Brasseur, P.; Verron, J. A.; Djath, B.; Duran, M.; Gaultier, L.; Gourdeau, L.; Melet, A.; Molines, J. M.; Ubelmann, C.
The upcoming high-resolution SWOT altimetry satellite will provide an unprecedented description of the ocean dynamic topography for studying sub- and meso-scale processes in the ocean. But there is still much uncertainty on the signal that will be observed. There are many scientific questions that are unresolved about the observability of altimetry at vhigh resolution and on the dynamical role of the ocean meso- and submesoscales. In addition, SWOT data will raise specific problems due to the size of the data flows. These issues will probably impact the data assimilation approaches for future scientific or operational oceanography applications. In this work, we propose to use a high-resolution numerical model of the Western Pacific Solomon Sea as a regional laboratory to explore such observability and dynamical issues, as well as new data assimilation challenges raised by SWOT. The Solomon Sea connects subtropical water masses to the equatorial ones through the low latitude western boundary currents and could potentially modulate the tropical Pacific climate. In the South Western Pacific, the Solomon Sea exhibits very intense eddy kinetic energy levels, while relatively little is known about the mesoscale and submesoscale activities in this region. The complex bathymetry of the region, complicated by the presence of narrow straits and numerous islands, raises specific challenges. So far, a Solomon sea model configuration has been set up at 1/36° resolution. Numerical simulations have been performed to explore the meso- and submesoscales dynamics. The numerical solutions which have been validated against available in situ data, show the development of small scale features, eddies, fronts and filaments. Spectral analysis reveals a behavior that is consistent with the SQG theory. There is a clear evidence of energy cascade from the small scales including the submesoscales, although those submesoscales are only partially resolved by the model. In parallel
The American Satellite Company (ASC) communications satellite is deployed from the payload bay of the Shuttle Discovery. A portion of the cloudy surface of the earth can be seen to the left of the frame.
The paper concerns the work of the Kingsbury Laboratories of Fairey Engineering Company, for the nuclear industry. The services provided include: monitoring of nuclear graphite machining, specialist welding, non-destructive testing, and metallurgy testing; and all are briefly described. (U.K.)
Lehner, S.; Hoja, D.; Schulz-Stellenfleth, J.
In 2001 the European Space Agency ESA will launch the earth observation satellite ENVISAT. It will carry several instruments that provide new opportunities to measure oceanographic variables. Together, they represent the main measurement techniques of satellite oceanography, and complement each other in an ideal manner. These instruments are to be used in synergy to: Improve the analysis of measured wind and ocean wave fields, and thereby improve weather forecasting at weather centers; Determine the extent and variables of sea ice and develop a five-day sea ice prediction model, to support maritime shipping and offshore activities; Monitor and map sediment and suspended matter transport in coastal regions, especially in areas with large river estuaries, which greatly affects shipping lanes, harbors, and dredging activities; Monitor hydrobiological and bio-geochemical variables related to water quality in coastal regions and large inland waters, which affects ecology, coastal development, aquaculture, drinking water supplies, and tourism. To prepare the oceanographic community to make best use of the ENVISAT sensors in the pre-launch phase, existing algorithms to derive marine parameters are used and validated using data from the ERS SAR, the ERS RA, SeaWiFS and IRS MOS sensors now in operation. Derived products are used to address problems that can best be tackled using the synergy of radar and optical data, such as the effect of surface slicks on radar wind measurements, of sea state on ocean color, of wind and waves on the resuspension of suspended matter, and of wind and waves on sea ice variables.
programmed for eventual integration with the Iridium Network , which is then tested. C. THESIS ORGANIZATION The thesis addresses these questions...NPS FEMTO SATELLITE FOR ALTERNATIVE SATELLITE COMMUNICATION NETWORKS by Faisal S. Alshaya September 2017 Co-Advisors: Steven J. Iatrou...TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE LEVERAGING THE NPS FEMTO SATELLITE FOR ALTERNATIVE SATELLITE COMMUNICATION NETWORKS 5
Best, Jr., Richard A; Elsea, Jennifer K
... and law enforcement purposes, in addition to the civil applications that have been supported for years. In 2007, it moved to transfer responsibility for coordinating civilian use of satellites to the Department of Homeland Security. The transfer occurred, however, apparently without notification of key congressional oversight committees.
are available for several generalized Zooplankton taxonomies (cope- pod-like, euphausiid-like, bubble-bearing fish larvae, salp -like, etc.), most...this CD-ROM you will travel via the 3-D animated submarine to seven undersea laboratories, each focusing on a different ecological theme to...present perspectives on interdisciplinary and international aquatic science research programs and building a successful career. Sympo- sium travel
Ciaffoni, O.; Ferrer, M.L.; Trasatti, L.
Possible technical solutions to the problem of high speed data links between laboratories are presented. Long distance networks (WAN), ranging from tens to hundreds of kilometers, offer a variety of possibilities, from standard 64 Kbit/s connections to optical fiber links and radio or satellite Mbit channels. Short range (up to 2-3 km) communications are offered by many existing LAN (local area network) standards up to 10 Mbit/s. The medium distance range (around 10 km) can be covered by high performance fiber optic links and the now emerging MAN (metropolitan area network) protocols. A possible area of application is between the Gran Sasso Tunnel Laboratory, the outside installations and other Italien and foreign laboratories. (orig.)
Davies, P.; Liddle, Doug; Paffett, John; Sweeting, Martin; Curiel, A.; Sun, Wei; Eves, Stuart
In order to achieve an "economy of scale" with respect to payload capacity the major trend in telecommunications satellites is for larger and larger platforms. With these large platforms the level of integration between platform and payload is increasing leading to longer delivery schedules. The typical lifecycle for procurement of these large telecommunications satellites is now 3-6 years depending on the level of non-recurring engineering needed. Surrey Satellite Technology Ltd (SSTL) has designed a low-cost platform aimed at telecommunications and navigation applications. SSTL's Geostationary Minisatellite Platform (GMP) is a new entrant addressing the lower end of the market with payloads up to 250kg requiring less than 1.5 kW power. The British National Space Centre through the MOSAIC Small Satellite Initiative supported the development of GMP. The main design goals for GMP are low-cost for the complete mission including launch and operations and a platform allowing flexible payload accommodation. GMP is specifically designed to allow rapid development and deployment with schedules typically between 1 and 2 years from contract signature to flight readiness. GMP achieves these aims by a modular design where the level of integration between the platform and payload is low. The modular design decomposes the satellite into three major components - the propulsion bay, the avionics bay and the payload module. Both the propulsion and avionics bays are reusable, largely unchanged, and independent of the payload configuration. Such a design means that SSTL or a 3rd party manufacturer can manufacture the payload in parallel to the platform with integration taking place quite late in the schedule. In July 2003 SSTL signed a contract for ESA's first Galileo navigation satellite known as GSTBV2/A. The satellite is based on GMP and ESA plan to launch it into a MEO orbit late in 2005. The second flight of GMP is likely to be in 2006 carrying a geostationary payload
Temperature, salinity, chlorophyll pigments, nutrients and other parameters as part of the ECOHAB-GOM: The Ecology and Oceanography of Toxic Alexandrium Blooms in the Gulf of Maine project (NODC Accession 0064309)
National Oceanic and Atmospheric Administration, Department of Commerce — The subproject described here is one of several components of ECOHAB-GOM: The Ecology and Oceanography of Toxic Alexandrium Blooms in the Gulf of Maine, a multi-PI,...
Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-11-05 to 2016-02-18 (NCEI Accession 0145664)
National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...
Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-03-10 to 2016-06-28 (NCEI Accession 0155280)
National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...
Physical trajectory profile data from glider sp064 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-05-17 to 2016-08-23 (NCEI Accession 0156410)
National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group (supported by NOAA). The National Centers for Environmental...
Physical trajectory profile data from glider sp050 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2016-03-30 to 2016-07-20 (NCEI Accession 0155979)
Physical trajectory profile data from glider sp064 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-10-30 to 2016-02-03 (NCEI Accession 0145715)
Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-09-13 to 2016-12-14 (NCEI Accession 0157580)
Physical trajectory profile data from glider sp056 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-03-29 to 2017-07-01 (NCEI Accession 0164292)
National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...
Physical trajectory profile data from glider sp039 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-01-22 to 2015-07-16 (NCEI Accession 0138033)
Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-01-09 to 2015-04-27 (NCEI Accession 0137984)
Physical trajectory profile data from glider sp035 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-03-31 to 2015-07-16 (NCEI Accession 0138032)
Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-05-01 to 2014-08-13 (NCEI Accession 0137974)
Physical trajectory profile data from glider sp001 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-01-12 to 2015-04-08 (NCEI Accession 0137973)
Physical trajectory profile data from glider sp063 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-02-03 to 2016-05-17 (NCEI Accession 0153552)
Physical trajectory profile data from glider sp063 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-09-15 to 2014-11-04 (NCEI Accession 0137991)
Physical trajectory profile data from glider sp052 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-08-14 to 2015-01-09 (NCEI Accession 0137990)
Physical trajectory profile data from glider sp050 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2015-02-06 to 2015-05-14 (NCEI Accession 0137988)
Physical trajectory profile data from glider sp018 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2014-06-10 to 2014-09-21 (NCEI Accession 0138030)
Physical trajectory profile data from glider sp053 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-08-29 to 2015-12-13 (NCEI Accession 0145713)
Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-11-30 to 2017-03-14 (NCEI Accession 0162197)
Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-08-17 to 2016-09-16 (NCEI Accession 0156601)
Physical trajectory profile data from glider sp031 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2015-09-10 to 2015-12-16 (NCEI Accession 0145667)
Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-11-25 to 2014-11-27 (NCEI Accession 0137979)
Physical trajectory profile data from glider sp039 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-02-18 to 2016-09-06 (NCEI Accession 0156570)
Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-11-24 to 2016-03-10 (NCEI Accession 0145666)
Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-06-28 to 2016-08-23 (NCEI Accession 0156400)
Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-08-13 to 2015-11-18 (NCEI Accession 0145665)
Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-06-11 to 2014-09-15 (NCEI Accession 0137978)
Physical trajectory profile data from glider sp053 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2016-07-20 to 2016-10-20 (NCEI Accession 0156796)
Physical trajectory profile data from glider sp041 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-09-08 to 2016-12-14 (NCEI Accession 0157607)
Physical trajectory profile data from glider sp042 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2016-11-04 to 2017-02-23 (NCEI Accession 0161310)
Physical trajectory profile data from glider sp052 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-07-28 to 2016-02-18 (NCEI Accession 0145670)
Physical trajectory profile data from glider sp064 deployed by University of California - San Diego; Scripps Institution of Oceanography in the |Coastal Waters of California from 2016-12-14 to 2017-03-29 (NCEI Accession 0162258)
Physical trajectory profile data from glider sp024 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2017-01-30 to 2017-05-08 (NCEI Accession 0162888)
National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...
Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-12-14 to 2017-03-28 (NCEI Accession 0162257)
Physical trajectory profile data from glider sp001 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2016-08-15 to 2016-11-16 (NCEI Accession 0157002)
Physical trajectory profile data from glider sp026 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2017-04-20 to 2017-07-31 (NCEI Accession 0164709)
National Oceanic and Atmospheric Administration, Department of Commerce — Spray glider profile data from Scripps Institution of Oceanography Instrument Development Group. (This deployment supported by NOAA.) The National Centers for...
Physical trajectory profile data from glider sp054 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-03-17 to 2016-10-11 (NCEI Accession 0156772)
Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-02-18 to 2016-06-02 (NCEI Accession 0153551)
Physical trajectory profile data from glider sp055 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-03-14 to 2017-06-28 (NCEI Accession 0163867)
Physical trajectory profile data from glider sp052 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-09-06 to 2017-03-14 (NCEI Accession 0162198)
Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-04-05 to 2017-07-11 (NCEI Accession 0164208)
Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-03-28 to 2017-07-11 (NCEI Accession 0164207)
Physical trajectory profile data from glider sp049 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2017-05-18 to 2017-08-24 (NCEI Accession 0165396)
Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-09-06 to 2016-11-30 (NCEI Accession 0157115)
Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-06-02 to 2016-09-06 (NCEI Accession 0156569)
Physical trajectory profile data from glider sp006 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-12-14 to 2016-03-30 (NCEI Accession 0153787)
Physical trajectory profile data from glider sp028 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-06-05 to 2014-09-05 (NCEI Accession 0137981)
Physical trajectory profile data from glider sp047 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-08-27 to 2016-03-17 (NCEI Accession 0145668)
Physical trajectory profile data from glider sp027 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2015-06-16 to 2015-09-23 (NCEI Accession 0145712)
Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-09-23 to 2015-01-09 (NCEI Accession 0137975)
Physical trajectory profile data from glider sp063 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-08-23 to 2016-08-28 (NCEI Accession 0156530)
Physical trajectory profile data from glider sp011 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-04-27 to 2015-08-13 (NCEI Accession 0137976)
Physical trajectory profile data from glider sp030 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-08-13 to 2014-11-25 (NCEI Accession 0137983)
Physical trajectory profile data from glider sp040 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-04-09 to 2015-07-14 (NCEI Accession 0138034)
Physical trajectory profile data from glider sp051 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-11-12 to 2015-01-08 (NCEI Accession 0137989)
Physical trajectory profile data from glider sp020 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2015-12-16 to 2016-03-30 (NCEI Accession 0153550)
Physical trajectory profile data from glider sp048 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-01-27 to 2015-08-27 (NCEI Accession 0145669)
Physical trajectory profile data from glider sp025 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2015-01-08 to 2015-04-09 (NCEI Accession 0137980)
Physical trajectory profile data from glider sp048 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-01-16 to 2014-07-29 (NCEI Accession 0138035)
Physical trajectory profile data from glider sp047 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2014-06-23 to 2015-01-22 (NCEI Accession 0137987)
Physical trajectory profile data from glider sp020 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2014-08-03 to 2014-12-12 (NCEI Accession 0137977)
Physical trajectory profile data from glider sp031 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Equatorial Pacific Ocean from 2014-04-12 to 2014-08-02 (NCEI Accession 0138031)
Physical trajectory profile data from glider sp018 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Solomon Sea from 2016-02-18 to 2016-05-28 (NCEI Accession 0153549)
Physical trajectory profile data from glider sp049 deployed by University of California - San Diego; Scripps Institution of Oceanography in the Coastal Waters of California from 2016-04-05 to 2016-06-02 (NCEI Accession 0153788)
National Oceanic and Atmospheric Administration, Department of Commerce — The Hurricane Satellite (HURSAT) from Microwave (MW) observations of tropical cyclones worldwide data consist of raw satellite observations. The data derive from the...
National Oceanic and Atmospheric Administration, Department of Commerce — This collection contains an operational Satellite Ocean Heat Content Suite (SOHCS) product generated by NOAA National Environmental Satellite, Data, and Information...
real-world satellite applications can quantify cyanobacterial harmful algal blooms and related water quality parameters. Provisional satellite derived cyanobacteria data and different software tools are available to state environmental and health agencies.
National Oceanic and Atmospheric Administration, Department of Commerce — The Defense Meteorological Satellite Program (DMSP) satellites collect visible and infrared cloud imagery as well as monitoring the atmospheric, oceanographic,...
Chernesky, Vincent S.
The Three Axis Satellite Simulator (TASS) is a 4-foot diameter octagonal platform supported on a spherical air bearing. The platform hosts several satellite subsystems, including rate gyros, reaction wheels, thrusters, sun sensors, and an onboard control computer. This free-floating design allows for realistic emulation of satellite attitude dynamics in a laboratory environment. The bifocal relay mirror spacecraft system is composed of two optically coupled telescopes used to redirect the las...
Federal Laboratory Consortium — The Saxton Transportation Operations Laboratory (Saxton Laboratory) is a state-of-the-art facility for conducting transportation operations research. The laboratory...
Luo, B.; Minnett, P. J.; Szczodrak, G.; Kilpatrick, K. A.
Infrared satellite observations of sea surface temperature (SST) have become essential for many applications in meteorology, climatology, and oceanography. Applications often require high accuracy SST data: for climate research and monitoring an absolute uncertainty of 0.1K and stability of better than 0.04K per decade are required. Tropospheric aerosol concentrations increase infrared signal attenuation and prevent the retrieval of accurate satellite SST. We compare satellite-derived skin SST with measurements from the Marine-Atmospheric Emitted Radiance Interferometer (M-AERI) deployed on ships during the Aerosols and Ocean Science Expeditions (AEROSE) and with quality-controlled drifter temperatures. After match-up with in-situ SST and filtering of cloud contaminated data, the results indicate that SST retrieved from MODIS (Moderate Resolution Imaging Spectroradiometer) aboard the Terra and Aqua satellites have negative (cool) biases compared to shipboard radiometric measurements. There is also a pronounced negative bias in the Saharan outflow area that can introduce SST errors >1 K at aerosol optical depths > 0.5. In this study, we present a new method to derive night-time Saharan Dust Index (SDI) algorithms based on simulated brightness temperatures at infrared wavelengths of 3.9, 10.8 and 12.0 μm, derived using RTTOV. We derived correction coefficients for Aqua MODIS measurements by regression of the SST errors against the SDI. The biases and standard deviations are reduced by 0.25K and 0.19K after the SDI correction. The goal of this study is to understand better the characteristics and physical mechanisms of aerosol effects on satellite retrieved infrared SST, as well as to derive empirical formulae for improved accuracies in aerosol-contaminated regions.
Our task is to design mined-repository systems that will adequately secure high-level nuclear waste for at least 10,000 yr and that will be mechanically stable for 50 to 100-yr periods of retrievability during which mistakes could be corrected and a valuable source of energy could be reclaimed, should national policy on the reprocessing of spent fuel ever change. The only credible path for the escape of radionuclides from the repository to the biosphere is through ground-water, and in hard rock, bulk permeability is largely governed by natural and artificial fracture systems. Catastrophic failure of an excavation in hard rock is likely to occur at the weakest links - the discontinuities in the rock mass that is perturbed first by mining and then by radiogenic heating. The laboratory can contribute precise measurements of the pertinent thermomechanical, hydrological and chemical properties and improve our understanding of the fundamental processes through careful experiments under well controlled conditions that simulate the prototype environment. Thus laboratory investigations are necessary, but they are not sufficient, for conventional sample sizes are small relative to natural defects like joints - i.e., the rock mass is not a continuum - and test durations are short compared to those that predictive modeling must take into account. Laboratory investigators can contribute substantially more useful data if they are provided facilities for testing large specimens(say one cubic meter) and for creep testing of all candidate host rocks. Even so, extrapolations of laboratory data to the field in neither space nor time are valid without the firm theoretical foundations yet to be built. Meanwhile in-situ measurements of structure-sensitive physical properties and access to direct observations of rock-mass character will be absolutely necessary
The report contains summaries of work carried out under the following headings: fusion research experiments; U.K. contribution to the JET project; supporting studies; theoretical plasma physics, computational physics and computing; fusion reactor studies; engineering and technology; contract research; external relations; staff, finance and services. Appendices cover main characteristics of Culham fusion experiments, staff, extra-mural projects supported by Culham Laboratory, and a list of papers written by Culham staff. (U.K.)
Seamster, A.G.; Weitkamp, W.G.
The lead plating of the prototype resonator has been conducted entirely in the plating laboratory at SUNY Stony Brook. Because of the considerable cost and inconvenience in transporting personnel and materials to and from Stony Brook, it is clearly impractical to plate all the resonators there. Furthermore, the high-beta resonator cannot be accommodated at Stony Brook without modifying the set up there. Consequently the authors are constructing a plating lab in-house
Bettini, A., E-mail: Bettini@pd.infn.i [Padua University and INFN Section, Dipartimento di Fisca G. Galilei, Via Marzolo 8, 35131 Padova (Italy); Laboratorio Subterraneo de Canfranc, Plaza Ayuntamiento n1 2piso, Canfranc (Huesca) (Spain)
Underground laboratories provide the low radioactive background environment necessary to frontier experiments in particle and nuclear astrophysics and other disciplines, geology and biology, that can profit of their unique characteristics. The cosmic silence allows to explore the highest energy scales that cannot be reached with accelerators by searching for extremely rare phenomena. I will briefly review the facilities that are operational or in an advanced status of approval around the world.
Investigates the provision of library services via satellite, explains briefly the operation and advantages of communication satellites, and discusses the various telecommunications equipment and services which, when coupled with satellite transmission, will enhance library activities. Demand trend projections for telecommunications services…
DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)
This project centers around the Strategic Petroleum Site (SPR) known as the West Hackberry salt dome which is located in southwestern Louisiana and which is designed to store 241 million barrels of crude oil. Oil storage caverns are formed by injecting water into salt deposits, and pumping out the resulting brine. Studies described in this report were designed as follow-on studies to three months of pre-discharge characterization work, and include data collected during the first year of brine leaching operations. The objectives were to: (1) characterize the environment in terms of physical, chemical and biological attributes; (2) determine if significant adverse changes in ecosystem productivity and stability of the biological community are occurring as a result of brine discharge; and (3) determine the magnitude of any change observed. Volume IV contains the following: bibliography; appendices for supporting data for physical oceanography, and summary of the physical oceanography along the western Louisiana coast.
Information Support laboratory, Geostationary Operational Meteorological Satellite. (Moscow, RU: SMIS IKI RAN and SRC PLANETA , January 2003); Internet...Operational Meteorological Satellite. Moscow, RU: SMIS IKI RAN and SRC PLANETA , January 2003. Squitieri, Tom. “In Bosnia, Weather is primary Foe”. USA Today
National Aeronautics and Space Administration — Payload Systems Inc. (PSI) and the MIT Space Systems Laboratory (MIT-SSL) propose an innovative research program entitled SPHERES-ISS that uses their satellite...
Perera, V.; Cotto-Figueroa, D.; Noviello, J.; Asphaug, E.; Morris, M.
Both the study of primary accretion and the surface properties of asteroids are important for the field of planetary science. The Asteroid Origins Satellite (AOSAT) will help study these subjects by creating a long duration microgravity laboratory.
Physical, Biological, and Acoustic Signals on Marine Mammal Habitat Use Physical Oceanography Component: Soundscapes Under Sea Ice: Can we listen for... Soundscapes Under Sea Ice: Can we listen for open water? 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...the source. These different sounds can be described as “ soundscapes ”, and graphically represented by comparing two or more features of the sound
Nakasuka, S.; Kawashima, R.
in Japan especially centered on micro or nano class satellites. Hands-on training using micro-nano satellites provide unique opportunity of space education to university level students, by giving them a chance to experience the whole space project cycle from mission creation, satellite design, fabrication, test, launch, operation through analysis of the results. Project management and team working are other important skills that can be trained in these projects. include 1) low cost, which allows one laboratory in university to carry out a project, 2) short development period such as one or two year, which enables students to obtain the results of their projects before they graduate, and 3) small size and weight, which enables fabrication and test within usually very narrow university laboratory areas. In Japan, several projects such as CanSat, CubeSat or Whale Observation Satellite have been carried out, proving that micro-nano satellites provide very unique and valuable educational opportunity. with the objective to make a university student and staff community of these micro-nano satellite related activities in Japan. This consortium aims for many activities including facilitating information and skills exchange and collaborations between member universities, helping students to use ground test facilities of national laboratories, consulting them on political or law related matters, coordinating joint development of equipments or projects, and bridging between these university activities and the needs or interests of the people in general. This kind of outreach activity is essential because how to create missions of micro-nano satellites should be pursued in order for this field to grow larger than a merely educational enterprise. The final objectives of the consortium is to make a huge community of the users, mission creators, investors and manufactures(i.e., university students) of micro-nano satellites, and provide a unique contribution to the activation of
P R Renosh
Full Text Available Satellite remote sensing observations allow the ocean surface to be sampled synoptically over large spatio-temporal scales. The images provided from visible and thermal infrared satellite observations are widely used in physical, biological, and ecological oceanography. The present work proposes a method to understand the multi-scaling properties of satellite products such as the Chlorophyll-a (Chl-a, and the Sea Surface Temperature (SST, rarely studied. The specific objectives of this study are to show how the small scale heterogeneities of satellite images can be characterised using tools borrowed from the fields of turbulence. For that purpose, we show how the structure function, which is classically used in the frame of scaling time series analysis, can be used also in 2D. The main advantage of this method is that it can be applied to process images which have missing data. Based on both simulated and real images, we demonstrate that coarse-graining (CG of a gradient modulus transform of the original image does not provide correct scaling exponents. We show, using a fractional Brownian simulation in 2D, that the structure function (SF can be used with randomly sampled couple of points, and verify that 1 million of couple of points provides enough statistics.
Pinck, D. S.
This presentation focuses on the activities at JPL on the integration of satellite and terrestrial networks for mobile and personal communications. Activities fall into two categories: 1)advanced systems work, and 2)laboratory and field experimentation. Results of a workshop held at JPL on PCS integration and interoperability will be presented. Experiments will be described.
Somayajulu, Y. V.; Mathur, B. S.; Banerjee, P.; Garg, S. C.; Singh, L.; Sood, P. C.; Tyagi, T. R.; Jain, C. L.; Kumar, K.
A recent clock synchronization experiment between the National Physical Laboratory (NPL), New Delhi and Space Applications Center (SAC), Ahemedabad, in India via geostationary satellite symphonie 2, stationed at 49 E longitude, is reported. A two-way transmission using a microwave transponder considered to provide the greatest precision in synchronization of two remote clocks is described.
Ferrera, G. A.
In 1982, the Infrared Astronomy Satellite (IRAS) will be launched into a 900-km sun-synchronous (twilight) orbit to perform an unbiased, all-sky survey of the far-infrared spectrum from 8 to 120 microns. Observations telemetered to ground stations will be compiled into an IR astronomy catalog. Attention is given the cryogenically cooled, 60-cm Ritchey-Chretien telescope carried by the satellite, whose primary and secondary mirrors are fabricated from beryllium by means of 'Cryo-Null Figuring'. This technique anticipates the mirror distortions that will result from cryogenic cooling of the telescope and introduces dimensional compensations for them during machining and polishing. Consideration is also given to the interferometric characterization of telescope performance and Cryo/Thermal/Vacuum simulated space environment testing.
parameters and stability of Van Allen belt are constantly modified by natural non-seismic and man-made processes. Therefore, in order to identify seismo-associated perturbations, it is needed to reject the "normal" background effects of the e.m. emissions due to: geomagnetic storms, tropospheric phenomena, and artificial sources (such as power lines, VLF transmitters, HF stations, etc.). Currently, the only available large database is that collected by the Demeter satellite and by rare observations made by some previous space missions, non-dedicated to this purpose. The CSES satellite aims at continuing the exploration started by Demeter with advanced multi-parametric measurements. The configuration of the CSES sensors foresees measurements of energetic particle fluxes, ionospheric plasma parameters and electromagnetic fields, in a wide range of energy and frequencies. The main sensors onboard the satellite are: the HEPD (High Energy Particle Detector) developed by the Italian participants, and the following Chinese sensors: LEPD (Low Energy Particle Detector), LP (Langmuir Probes), IDM (Ion Drift Meter), ICM (Ion Capture Meter), RPA (Retarding Potential Analyzer), EFD (Electric Field Detectors) developed in collaboration with Italian team, HPM (High Precision Magnetometer) and SCM (Search-Coil Magnetometer). The research activity is at an advanced phase, being the various payloads already built and, right now, an intense activity is going on for calibration of the various sensors. In particular, the Italian payload HEPD is under test at the laboratories of the National Institute for Nuclear Physics (INFN) and the Chinese payloads LP, IDM, ICM, RPA and EFD are tested at the INAF-IAPS "Plasma Chamber" in Rome, which is a facility where the response of the sensors, and their compatibility with ionospheric plasma, can be verified in environmental conditions very similar to those met by the satellite in orbit.
Thematic Mapping from Satellite Imagery: A Guidebook discusses methods in producing maps using satellite images. The book is comprised of five chapters; each chapter covers one stage of the process. Chapter 1 tackles the satellite remote sensing imaging and its cartographic significance. Chapter 2 discusses the production processes for extracting information from satellite data. The next chapter covers the methods for combining satellite-derived information with that obtained from conventional sources. Chapter 4 deals with design and semiology for cartographic representation, and Chapter 5 pre
Chatzinotas, Symeon; De Gaudenzi, Riccardo
Cooperative and Cognitive Satellite Systems provides a solid overview of the current research in the field of cooperative and cognitive satellite systems, helping users understand how to incorporate state-of-the-art communication techniques in innovative satellite network architectures to enable the next generation of satellite systems. The book is edited and written by top researchers and practitioners in the field, providing a comprehensive explanation of current research that allows users to discover future technologies and their applications, integrate satellite and terrestrial systems
Richardson, M. J.; Gardner, W. D.
Over the last seven years we have led the creation and implementation of the Oceanography and Geoscience Scholars programs at Texas A&M University. Through these programs we have been able to provide scholarship support for 92 undergraduates in Geosciences and 29 graduate students in Oceanography. Fifty-seven undergraduate scholars have graduated in Geosciences: 30 undergraduate students in Meteorology, 7 in Geology, and 20 in Environmental Geosciences. Two students have graduated in other STEM disciplines. Twenty-four students are in the process of completing their undergraduate degrees in STEM disciplines. Twenty-three students have graduated with MS or PhD degrees in Oceanography and five PhD students are completing their dissertations. As specified in the program solicitation all of the scholars are academically talented students with demonstrated financial need as defined by the FAFSA (Free Application for Federal Student Aid). We have endeavored to recruit students from underrepresented groups. One-third of the undergraduate scholars were from underrepresented groups; 28% of the graduate students. We will present the challenges and successes of these programs.
Ladd, Carol; Cheng, Wei; Salo, Sigrid
Frequent gap winds, defined here as offshore-directed flow channeled through mountain gaps, have been observed near Kodiak Island in the Gulf of Alaska (GOA). Gap winds from the Iliamna Lake gap were investigated using QuikSCAT wind data. The influence of these wind events on the regional ocean was examined using satellite and in situ data combined with Regional Ocean Modeling System (ROMS) model runs. Gap winds influence the entire shelf width (> 200 km) northeast of Kodiak Island and extend an additional 150 km off-shelf. Due to strong gradients in the along-shelf direction, they can result in vertical velocities in the ocean of over 20 m d-1 due to Ekman pumping. The wind events also disrupt flow of the Alaska Coastal Current (ACC), resulting in decreased flow down Shelikof Strait and increased velocities on the outer shelf. This disruption of the ACC has implications for freshwater transport into the Bering Sea. The oceanographic response to gap winds may influence the survival of larval fishes as Arrowtooth Flounder recruitment is negatively correlated with the interannual frequency of gap-wind events, and Pacific Cod recruitment is positively correlated. The frequency of offshore directed winds exhibits a strong seasonal cycle averaging 7 days per month during winter and 2 days per month during summer. Interannual variability is correlated with the Pacific North America Index and shows a linear trend, increasing by 1.35 days per year. An accompanying paper discusses part I of our study (Ladd and Cheng, 2016) focusing on gap-wind events flowing out of Cross Sound in the eastern GOA.
Satellite Photometric Error Determination Tamara E. Payne, Philip J. Castro, Stephen A. Gregory Applied Optimization 714 East Monument Ave, Suite...advocate the adoption of new techniques based on in-frame photometric calibrations enabled by newly available all-sky star catalogs that contain highly...filter systems will likely be supplanted by the Sloan based filter systems. The Johnson photometric system is a set of filters in the optical
At this workshop a group of expert scientists: (1) assessed the current state of knowledge with regard to the physical oceanographic questions that must be answered generally if high level nuclear waste is to be disposed of on or under the seabed; (2) discussed physical oceanographic science necessarily related to the US Subseabed Disposal Program; (3) recommended necessary research; and (4) identified other ongoing programs with which important liaisons should be made and continued. This report is a collection of workshop presentations, and recommendations, and a synthesis of topical group recommendations into a unified statement of research needs. The US Seabed Disposal Program is described. The goal is to assess the technical, environmental and engineering feasibility of seabed disposal. The environmental studies program will assess possible ecosystem and health effects from radionuclides which may be released due to accidental leakage. Discussion on the following topics are also included: bottom boundary layer; mixing across isopycnal surfaces; circulation modeling; mesoscale dispersion; deep circulation of the Pacific Ocean; vertical transport at edges; instrumentation; chemical oceanography; plutonium distribution in the Pacific; biology report; chemical dumping report; and low-level waste report
Sánchez-Arcilla, Agustín; Wolf, Judith; Monbaliu, Jaak
The high-resolution and coupled forecasting of wind, waves and currents, in restricted coastal domains, offer a number of important challenges; these limit the quality of predictions, in the present state-of-the-art. This paper presents the main results obtained for such coastal domains, with reference to a variety of modelling suites and observing networks for: a) Liverpool Bay; b) German Bight; c) Gulf of Venice; and d) the Catalan coast. All of these areas are restricted domains, where boundary effects play a significant role in the resulting inner dynamics. This contribution addresses also the themes of the other papers in this Special Issue, ranging from observations to simulations. Emphasis is placed upon the physics controlling such restricted areas. The text deals also with the transfer to end-users and other interested parties, since the requirements on resolution, accuracy and robustness must be linked to their applications. Finally, some remarks are included on the way forward for coastal oceanography and the synergetic combination of in-situ and remote measurements, with high-resolution 3D simulations.
Pagels, U.; Koehler, S.
Box cores recovered along a N-S transect in the Eurasian Basin allow the establishment of a time scale for the Late Quaternary history of the Arctic Ocean, based on stable oxygen isotope stratigraphy and AMS 14 C dating of planktonic foraminifers (N. pachyderma I.c.). This high resolution stratigraphy, in combination with sedimentological investigations (e.g. coarse fraction analysis, carbonate content, productivity of foraminifers), was carried out to reconstruct the glacial and inter-glacial Arctic Ocean palaeo-environment The sediment cores, which can be correlated throughout the sampling area in the Eastern Arctic Ocean, were dated as representing oxygen isotope stages 1 to 4/5. The sedimentation rates varied between a few mm/ka in glacials and approximately one cm/ka during the Holocene. The sediments allow a detailed sedimentological description of the depositional regime and the palaeo-oceanography of the Eastern Arctic Ocean. Changing ratios of biogenic and lithogenic components in the sediments reflect variations in the oceanographic circulation pattern in the Eurasian Basin during the Late Quaternary. Carbonate content (1-9wt.%), productivity of foraminifers (high in interglacial, low in glacial stages) and the terrigenous components are in good correlation with glacial and inter-glacial climatic fluctuations
McCalla, C., Sr.
The National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) provides weather, hydrologic, and climate forecasts and warnings for the protection of life and property and the enhancement of the national economy. The NWS's Meteorological Development Laboratory (MDL) supports this mission by developing meteorological prediction methods. Given this mission, NOAA, NWS, and MDL all have a need to continually recruit talented scientists. One avenue for recruiting such talented scientist is the Student Career Experience Program (SCEP). Through SCEP, MDL offers undergraduate and graduate students majoring in meteorology, computer science, mathematics, oceanography, physics, and statistics the opportunity to alternate full-time paid employment with periods of full-time study. Using SCEP as a recruiting vehicle, MDL has employed students who possess some of the very latest technical skills and knowledge needed to make meaningful contributions to projects within the lab. MDL has recently expanded its use of SCEP and has increased the number of students (sometimes called co- ops) in its program. As a co-op, a student can expect to develop and implement computer based scientific techniques, participate in the development of statistical algorithms, assist in the analysis of meteorological data, and verify forecasts. This presentation will focus on describing recruitment, projects, and the application process related to MDL's SCEP. In addition, this presentation will also briefly explore the career paths of students who successfully completed the program.
Tsuruda, Yoshihiro; Fujimoto, Akiko; Kurahara, Naomi; Hanada, Toshiya; Yumoto, Kiyohumi; Cho, Mengu
This paper introduces QSAT, the satellite for polar plasma observation. The QSAT project began in 2006 as an initiative by graduate students of Kyushu University, and has the potential to contribute greatly to IHY (International Heliophysical Year) by showing to the world the beauty, importance, and relevance of space science. The primary objectives of the QSAT mission are (1) to investigate plasma physics in the Earth’s aurora zone in order to better understand spacecraft charging, and (2) to conduct a comparison of the field-aligned current observed in orbit with ground-based observations. The QSAT project can provide education and research opportunities for students in an activity combining space sciences and satellite engineering. The QSAT satellite is designed to be launched in a piggyback fashion with the Japanese launch vehicle H-IIA. The spacecraft bus is being developed at the Department of Aeronautics and Astronautics of Kyushu University with collaboration of Fukuoka Institute of Technology. Regarding the payload instruments, the Space Environment Research Center of Kyushu University is developing the magnetometers, whereas the Laboratory of Spacecraft Environment Interaction Engineering of Kyushu Institute of Technology is developing the plasma probes. We aim to be ready for launch in 2009 or later.
Chambers, Katherine H.; Koschmeder, Louis A.; Hollansworth, James E.; ONeill, Jack; Jones, Robert E.; Gibbons, Richard C.
Emerging applications of commercial mobile satellite communications include satellite delivery of compact disc (CD) quality radio to car drivers who can select their favorite programming as they drive any distance; transmission of current air traffic data to aircraft; and handheld communication of data and images from any remote corner of the world. Experiments with the enabling technologies and tests and demonstrations of these concepts are being conducted before the first satellite is launched by utilizing an existing NASA spacecraft.
It is only during the past three decades that international interest has focused on the need to manage and nurture one of our most valued resources - the oceans. In spite of this growing recognition, however, it is only during the past ten years that international agreement has been reached on the control of dumping of wastes (including nuclear wastes) at sea. The International Laboratory of Marine Radioactivity was established in 1961 well before the international agreement came into force. Indeed the Laboratory came into existence as a result of the foresight and appreciation by the International Atomic Energy Agency of the need to attack the problem of the behaviour of radioactive substances in the oceans - a subject about which little was known prior to the 1950s. With the co-operation of the Government of Monaco and the Institut Oceanographique, the Laboratory was established in 1961 in the Musee Oceanographique, Monaco. It is appropriate that the Laboratory was established in a building created by one of the most prominent pioneers in oceanography - Prince Albert 1sup(er) of Monaco. Since 1961 the programme and activities of the Monaco Laboratory have expanded and changed with the changing emphasis in pollution problems in the oceans. Throughout the many changes in emphasis which have occurred during the past 20 years, however, it is probably fair to say that the broad objectives have remained the same. The Laboratory exists therefore: to perform research on the occurrence and behaviour of radioactive substances and other forms of pollution in the marine environment; to ensure the quality of the performance and comparability of studies of radioactive substances and other forms of pollution in the marine environment by national laboratories through inter-laboratory comparisons, calibration and standardization of methodology; to assist Member States with regard to marine radioactivity and environmental problems by training personnel, establishing co
Glynn, P. W.; Veron, J. E. N.; Wellington, G. M.
Coral reef geomorphology and community composition were investigated in the tropical northeastern Pacific during April 1994. Three areas were surveyed in the Revillagigedo Islands (Mexico), and an intensive study was conducted on Clipperton Atoll (1,300 km SW of Acapulco), including macro-scale surface circulation, sea surface temperature (SST) climatology, geomorphology, coral community structure, zonation, and biogeography. Satellite-tracked drifter buoys from 1979 1993 demonstrated complex patterns of surface circulation with dominantly easterly flow (North Equatorial Counter Current, NECC), but also westerly currents (South Equatorial Current, SEC) that could transport propagules to Clipperton from both central and eastern Pacific regions. The northernmost latitude reached by the NECC is not influenced by El Niño-Southern Oscillation (ENSO) events, but easterly flow velocity evidently is accelerated at such times. Maximum NECC flow rates indicate that the eastern Pacific barrier can be bridged in 60 to 120 days. SST anomalies at Clipperton occur during ENSO events and were greater at Clipperton in 1987 than during 1982 1983. Shallow (15 18 m)and deep (50 58 m) terraces are present around most of Clipperton, probably representing Modern and late Pleistocene sea level stands. Although Clipperton is a well developed atoll with high coral cover, the reef-building fauna is depauperate, consisting of only 7 species of scleractinian corals belonging to the genera Pocillopora, Porites, Pavona and Leptoseris, and 1 species of hydrocoral in the genus Millepora. The identities of the one Pocilpopora species and one of the two Porites species are still unknown. Two of the remaining scleractinians ( Pavona minuta, Leptoseris scabra) and the hydrocoral ( Millepora exaesa), all formerly known from central and western Pacific localities, represent new eastern Pacific records. Scleractinian corals predominate (10 100% cover) over insular shelf depths of 8 to 60m, and crustose
Dasenbrock, R. R.; Kaufman, B.; Heard, W. B.
The subject of satellite disintegration is examined in detail. Elements of the orbits of individual fragments, determined by DOD space surveillance systems, are used to accurately predict the time and place of fragmentation. Dual time independent and time dependent analyses are performed for simulated and real breakups. Methods of statistical mechanics are used to study the evolution of the fragment clouds. The fragments are treated as an ensemble of non-interacting particles. A solution of Liouville's equation is obtained which enables the spatial density to be calculated as a function of position, time and initial velocity distribution.
Weidenschilling, S.J.; Paolicchi, P.; Zappala, V.
A substantial body of indirect evidence suggests that some asteroids have satelities, although none has been detected unambiguously. Collisions between asteroids provide physically plausible mechanisms for the production of binaries, but these operate with low probability; only a small minority of asteroids are likely to have satellites. The abundance of binary asteroids can constrain the collisional history of the entire belt population. The allowed angular momentum of binaries and their rate of tidal evolution limit separations to no more than a few tens of the primary's radii. Their expected properties are consistent with failure to detect them by current imaging techniques
Liu, Jingnan; Fan, Shiwei; Wang, Feixue
These Proceedings present selected research papers from CSNC2016, held during 18th-20th May in Changsha, China. The theme of CSNC2016 is Smart Sensing, Smart Perception. These papers discuss the technologies and applications of the Global Navigation Satellite System (GNSS), and the latest progress made in the China BeiDou System (BDS) especially. They are divided into 12 topics to match the corresponding sessions in CSNC2016, which broadly covered key topics in GNSS. Readers can learn about the BDS and keep abreast of the latest advances in GNSS techniques and applications.
Liu, Jingnan; Yang, Yuanxi; Fan, Shiwei; Yu, Wenxian
These proceedings present selected research papers from CSNC2017, held during 23th-25th May in Shanghai, China. The theme of CSNC2017 is Positioning, Connecting All. These papers discuss the technologies and applications of the Global Navigation Satellite System (GNSS), and the latest progress made in the China BeiDou System (BDS) especially. They are divided into 12 topics to match the corresponding sessions in CSNC2017, which broadly covered key topics in GNSS. Readers can learn about the BDS and keep abreast of the latest advances in GNSS techniques and applications.
This book explains the basic principles of satellite navigation technology with the bare minimum of mathematics and without complex equations. It helps you to conceptualize the underlying theory from first principles, building up your knowledge gradually using practical demonstrations and worked examples. A full range of MATLAB simulations is used to visualize concepts and solve problems, allowing you to see what happens to signals and systems with different configurations. Implementation and applications are discussed, along with some special topics such as Kalman Filter and Ionosphere. W
Crises change the global pattern of communication. The communications problems occur because the satellites are optimized to cover specific geographic areas, and these areas cannot be altered once the satellites are in Earth orbit. An effective solution to the problem is to equip communication sa...... satellites with "living" antennas that can adjust their radiation coverage areas according to the new demands. The development of living antennas is, therefore, among the focus areas identified and supported by the European Space Agency, ESA....
Lincoln, N.K.; Veres, S.M.; Dennis, Louise; Fisher, Michael; Lisitsa, Alexei
A novel, hybrid, agent architecture for (small)swarms of satellites has been developed. The software architecture for each satellite comprises ahigh-level rational agent linked to a low-level control system. The rational agent forms dynamicgoals, decides how to tackle them and passes theactual implementation of these plans to the control layer. The rational agent also has access to aMatLabmodel of the satellite dynamics, thus allowing it to carry out selective hypothetical reasoningabout pote...
Johannsen, Klaus G.; Bowles, Mike W.; Milliken, Samuel; Cherrette, Alan R.; Busche, Gregory C.
Ever since the U.S. Federal Communication Commission opened the discussion on spectrum usage for personal handheld communication, the community of satellite manufacturers has been searching for an economically viable and technically feasible satellite mobile communication system. Hughes Aircraft Company and others have joined in providing proposals for such systems, ranging from low to medium to geosynchronous orbits. These proposals make it clear that the trend in mobile satellite communication is toward more sophisticated satellites with a large number of spot beams and onboard processing, providing worldwide interconnectivity. Recent Hughes studies indicate that from a cost standpoint the geosynchronous satellite (GEOS) is most economical, followed by the medium earth orbit satellite (MEOS) and then by the low earth orbit satellite (LEOS). From a system performance standpoint, this evaluation may be in reverse order, depending on how the public will react to speech delay and collision. This paper discusses the trends and various mobile satellite constellations in satellite communication under investigation. It considers the effect of orbital altitude and modulation/multiple access on the link and spacecraft design.
Olsen, Nils; Kotsiaros, Stavros
Although the first satellite observations of the Earth’s magnetic field were already taken more than 50 years ago, continuous geomagnetic measurements from space are only available since 1999. The unprecedented time-space coverage of this recent data set opened revolutionary new possibilities...... for exploring the Earth’s magnetic field from space. In this chapter we discuss characteristics of satellites measuring the geomagnetic field and report on past, present and upcoming magnetic satellite missions. We conclude with some basics about space magnetic gradiometry as a possible path for future...... exploration of Earth’s magnetic field with satellites....
Federal Laboratory Consortium — Description/History: Chemistry and biology laboratoriesThe Bio Engineering Laboratory (BeL) is theonly full spectrum biotechnology capability within the Department...
Federal Laboratory Consortium — This laboratory provides biomechanical and physical analyses for both military and commercial footwear. The laboratory contains equipment that is integral to the us...
Federal Laboratory Consortium — The Nanotechnology Characterization Laboratory (NCL) at the Frederick National Laboratory for Cancer Research performs preclinical characterization of nanomaterials...
Federal Laboratory Consortium — PNNL's Physical Sciences Laboratory (PSL) houses 22 research laboratories for conducting a wide-range of research including catalyst formulation, chemical analysis,...
Federal Laboratory Consortium — The Distributed Energy Technologies Laboratory (DETL) is an extension of the power electronics testing capabilities of the Photovoltaic System Evaluation Laboratory...
RameshKumar, M.R.; Muraleedharan, P.M.; Sathe, P.V.
shipping tained from the Physical Oceanography Data Archives Centre (PODAAC) of the Jet Propulsion Laboratory, U.S.A. We have excluded the data for the period July*Ocean Remote Sensing Section, National Institute of Oceanog- raphy, Dona Paula, Goa, India... and the central Indian Ocean are highly correlated with the mon-January 0.43 20.00002 April 0.54 20.00053 soon rainfall over the western and central parts of India July 0.44 20.04 during the same week. Based on 80 years of ship data October 0.18 20.00014 (1900...
Hoder, Douglas; Bergamo, Marcos
The advanced communication technology satellite (ACTS) gigabit satellite network provides long-haul point-to-point and point-to-multipoint full-duplex SONET services over NASA's ACTS. at rates up to 622 Mbit/s (SONET OC-12), with signal quality comparable to that obtained with terrestrial fiber networks. Data multiplexing over the satellite is accomplished using time-division multiple access (TDMA) techniques coordinated with the switching and beam hopping facilities provided by ACTS. Transmissions through the satellite are protected with Reed-Solomon encoding. providing virtually error-free transmission under most weather conditions. Unique to the system are a TDMA frame structure and satellite synchronization mechanism that allow: (a) very efficient utilization of the satellite capacity: (b) over-the-satellite dosed-loop synchronization of the network in configurations with up to 64 ground stations: and (c) ground station initial acquisition without collisions with existing signalling or data traffic. The user interfaces are compatible with SONET standards, performing the function of conventional SONET multiplexers and. as such. can be: readily integrated with standard SONET fiber-based terrestrial networks. Management of the network is based upon the simple network management protocol (SNMP). and includes an over-the-satellite signalling network and backup terrestrial internet (IP-based) connectivity. A description of the ground stations is also included.
Full Text Available On the occasion of the 35th year from the publication of the first issue of the Proceedings of the Italian Association of Limnology and Oceanography (AIOL we present here the results of a meta-analysis of all of the material included in the AIOL Proceedings, with the aim of analysing the last 30 years history of aquatic science in Italy as mirrored by the science presented by the AIOL members. The results of this meta-analysis were presented in September 2006 in Paris, on the occasion of the 100th anniversary of the ‘Institut oce´anographique, fondation Albert Ier, prince de Monaco’. We have screened the 17 volumes of the Proceedings and classified the articles into papers dealing with: (i Biology and Ecology; (ii Chemistry; (iii Physics, and (iv Geology, which represent the most relevant ‘disciplines’ of the AIOL. The articles were also classified as ‘oceanographic’ or ‘limnological’ papers, including all marine and freshwater aspects, respectively. Articles were finally classified on the basis of the environment where the studies were carried out: the water column or the benthic environment. The results of this analysis highlight the presence of wide fluctuations in the number of publications produced by the AIOL scientific community during more then three decades of the activity of the association in Italy. We also show that these fluctuations were associated with variable fluctuations in the availability of funding for aquatic research. The overall picture of the scientific outputs of the AIOL members as revealed by the analysis of the papers published on the AIOL Proceedings indicates that the Association had a fruitful activity during the last part of the past century, but experienced a major flaw during the first years of this century. Only in the last few years such activity restarted, thus giving rise to a possible new deal in the development of aquatic science in Italy.
Hedman, K.; Kirschner, S.; Seitz, F.
In the last decades there has been a rapid development of new geodetic and other Earth observation satellites. Applications of these satellites such as car navigation systems, weather predictions, and, digital maps (such as Google Earth or Google Maps) play a more and more important role in our daily life. For geosciences, satellite applications such as remote sensing and precise positioning/navigation have turned out to be extremely useful and are meanwhile indispensable. Today, researchers within geodesy, climatology, oceanography, meteorology as well as within Earth system science are all dependent on up-to-date satellite data. Design, development and handling of these missions require experts with knowledge not only in space engineering, but also in the specific applications. That gives rise to a new kind of engineers - satellite application engineers. The study program for these engineers combines parts of different classical disciplines such as geodesy, aerospace engineering or electronic engineering. The satellite application engineering program Earth Oriented Space Science and Technology (ESPACE) was founded in 2005 at the Technische Universität München, mainly from institutions involved in geodesy and aerospace engineering. It is an international, interdisciplinary Master's program, and is open to students with a BSc in both Science (e.g. Geodesy, Mathematics, Informatics, Geophysics) and Engineering (e.g. Aerospace, Electronical and Mechanical Engineering). The program is completely conducted in English. ESPACE benefits from and utilizes its location in Munich with its unique concentration of expertise related to space science and technology. Teaching staff from 3 universities (Technische Universität München, Ludwig-Maximilian University, University of the Federal Armed Forces), research institutions (such as the German Aerospace Center, DLR and the German Geodetic Research Institute, DGFI) and space industry (such as EADS or Kayser-Threde) are
Brian H Shirts
Full Text Available The clinical laboratory is a major source of health care data. Increasingly these data are being integrated with other data to inform health system-wide actions meant to improve diagnostic test utilization, service efficiency, and "meaningful use." The Academy of Clinical Laboratory Physicians and Scientists hosted a satellite meeting on clinical laboratory analytics in conjunction with their annual meeting on May 29, 2014 in San Francisco. There were 80 registrants for the clinical laboratory analytics meeting. The meeting featured short presentations on current trends in clinical laboratory analytics and several panel discussions on data science in laboratory medicine, laboratory data and its role in the larger healthcare system, integrating laboratory analytics, and data sharing for collaborative analytics. One main goal of meeting was to have an open forum of leaders that work with the "big data" clinical laboratories produce. This article summarizes the proceedings of the meeting and content discussed.
von der Dunk, Frans
there are the major categories of space applications—as these have started to impact everyday life on earth: the involvement of satellites in communications infrastructures and services, the most commercialized area of space applications yet; the special issue of space serving to mitigate disasters and their consequences on earth; the use of satellites for remote sensing purposes ranging from weather and climate monitoring to spying; and the use of satellites for positioning, navigation, and timing.
Discusses technical advances in satellite technology since the 1960s, and the International Telecommunications Satellite Organization's role in these developments; describes how AUSSAT, Australia's domestic satellite system, exemplifies the latest developments in satellite technology; and reviews satellite system features, possible future…
The construction, launch, components, and operations of satellite solar power systems (SSPS) for direct beaming of solar energy converted to electricity to earth stations are outlined. The reference designs of either Si or concentrator GaAs solar cell assemblies large enough to project 5 GW of power are described. The beam will be furnished by klystrons or amplitrons for reception by rectennas on earth. Conforming to the law of amplitude and the equiphase law will permit high efficiencies, pointing accuracy, and low power deposition/sq cm, thus avoiding environmental problems, although some telecommunications systems may suffer interference. The construction of the dipole rectenna grid is sketched, noting that one receiver would be an ellipse sized at 10 x 13 km. Various forms of pollution which could result from the construction of an SSPS are examined.
materials and chemicals, rocket propulsion, satellite technology, control and guidance system, etc. ... entire country, especially the rural areas, and in the survey and management of natural resources. Listeners are no .... satellite will store the information over a longer period and then on command from the ground station at ...
Cianca, Ernestina; De Sanctis, Mauro; De Luise, Aldo
Thus far, high-altitude platform (HAP)-based systems have been mainly conceived as an alternative to satellites for complementing the terrestrial network. This article aims to show that HAP should no longer be seen as a competitor technology by investors of satellites, but as a key element for an...
Replacing slower mail service, satellite transmission now gives the newspaper industry a practical and almost spontaneous method for sending all kinds of information to any newspaper across the country. Unlike other communication industries, newspapers did not begin to make widespread use of satellite technology until 1979, when government…
Propp, George; And Others
Originally part of a symposium on educational media for the deaf, the paper describes a satellite demonstration of video disc materials. It is explained that a panel of deaf individuals in Washington, D.C. and another in Nebraska came into direct two-way communication for the first time, and video disc materials were broadcast via the satellite.…
Information provided for school districts desiring to offer distance education courses to their students describes the kind of satellite dish needed; its size, sturdiness, placement, and number of dishes needed; satellite receivers; the function of a descrambler; copyright restrictions; features of an Integrated Receiver/Descrambler; selecting a…
The skeletal muscle satellite cell was first described and named based on its anatomic location between the myofiber plasma and basement membranes. In 1961, two independent studies by Alexander Mauro and Bernard Katz provided the first electron microscopic descriptions of satellite cells in frog and rat muscles. These cells were soon detected in other vertebrates and acquired candidacy as the source of myogenic cells needed for myofiber growth and repair throughout life. Cultures of isolated myofibers and, subsequently, transplantation of single myofibers demonstrated that satellite cells were myogenic progenitors. More recently, satellite cells were redefined as myogenic stem cells given their ability to self-renew in addition to producing differentiated progeny. Identification of distinctively expressed molecular markers, in particular Pax7, has facilitated detection of satellite cells using light microscopy. Notwithstanding the remarkable progress made since the discovery of satellite cells, researchers have looked for alternative cells with myogenic capacity that can potentially be used for whole body cell-based therapy of skeletal muscle. Yet, new studies show that inducible ablation of satellite cells in adult muscle impairs myofiber regeneration. Thus, on the 50th anniversary since its discovery, the satellite cell’s indispensable role in muscle repair has been reaffirmed. PMID:22147605
Johanson, Gary A.
This paper addresses the methods used or proposed for use in multi-beam and/or multi-satellite networks designed to provide Mobile Satellite Services (MSS). Specific topics include beam crossover in the North American Mobile Satellite (MSAT) system as well as registration and live call hand-off for a multi-regional geosynchronous (GEO) satellite based system and a global coverage Low Earth Orbiting (LEO) system. In the MSAT system, the individual satellite beams cover very large geographic areas so the need for live call hand-off was not anticipated. This paper discusses the methods used to keep track of the beam location of the users so that incoming call announcements or other messages may be directed to them. Proposed new GEO systems with large numbers of beams will provide much smaller geographic coverage in individual beams and thus the need arises to keep track of the user's location as well as to provide live call hand-off as the user traverses from beam to beam. This situation also occurs in proposed LEO systems where the problems are worsened by the need for satellite to satellite hand-off as well as beam to beam hand-off within a single satellite. The paper discusses methods to accomplish these handoffs and proposes system architectures to address the various hand-off scenarios.
Safronov, V.S.; Ruskol, E.L.
Formation and evolution of circumplanetary satellite swarms are investigated. Characteristic times of various processes are estimated. The characteristic time for the accumulation of the bodies in the swarm was several orders of magnitude shorter than that of the planet, i.e. than the time of the replenishment of the material by the swarm (10 8 yr). The model of the accumulation of the swarm is constructed taking into account the increase of its mass due to trapping of heliocentrically moving particles and its decrease due to outfall of the inner part of the swarm onto the growing planet. The accumulation of circumplanetary bodies is also considered. The main features of the evolution of the swarm essentially depend on the size distribution of bodies in the swarm and in the zone of the planet and also on the degree of the concentration of the swarm mass toward the planet. If the sum of the exponents of the inverse power laws of these distributions is less than 7, the model of the transparent swarm developed in this paper should be preferred. When this sum is greater than 7, the model of opaque swarm suggested by A. Harris and W.M. Kaula is better. There is predominant trapping of small particles into the swarm due to their more frequent collisions. Optical thickness of the protoplanetary cloud in radial direction is estimated. It is shown that at the final stage of the planetary accumulation, the cloud was semitransparent in the region of terrestrial planets and volatile substances evaporated at collisions could be swept out from the outer parts of the satellite swarm by the solar wind
How much do we depend on space satellites? Defense, travel, agriculture, weather forecasting, mobile phones and broadband, commerce...the list seems endless. But what would our live be like if the unimaginable happened and, by accident or design, those space assets disappeared? Sky Alert! explores what our world would be like, looking in turn at areas where the loss could have catastrophic effects. The book - demonstrates our dependence on space technology and satellites; - outlines the effect on our economy, defense, and daily lives if satellites and orbiting spacecraft were destroyed; - illustrates the danger of dead satellites, spent rocket stages, and space debris colliding with a functioning satellites; - demonstrates the threat of dramatically increased radiation levels associated with geomagnetic storms; - introduces space as a potential area of conflict between nations.
Sood, D. R.; Hoernig, O. W., Jr.
In connection with the growing importance of the commercial communication satellite systems and the introduction of new technological developments, users and operators of these systems become increasingly concerned with aspects of security. The user community is concerned with maintaining confidentiality and integrity of the information being transmitted over the satellite links, while the satellite operators are concerned about the safety of their assets in space. In response to these concerns, the commercial satellite operators are now taking steps to protect the communication information and the satellites. Thus, communication information is being protected by end-to-end encryption of the customer communication traffic. Attention is given to the selection of the NBS DES algorithm, the command protection systems, and the communication protection systems.
National Oceanic and Atmospheric Administration, Department of Commerce — Visible and Infrared satellite imagery taken from camera systems or radiometer instruments on satellites in orbit around the poles. Satellite campaigns include...
Chitumbo, K.; Bunney, J.; Leve, G.; Robb, S.
Full text: The presentation examines some of the challenges the Satellite Imagery and Analysis Laboratory (SIAL) is facing in supporting Strengthened Safeguards. It focuses on the analytical process, starting with specifying initial tasking and continuing through to end products that are a direct result of in-house analysis. In addition it also evaluates the advantages and disadvantages of SIAL's mission and introduces external forces that the agency must consider, but cannot itself, predict or control. Although SIAL's contribution to tasks relating to Article 2a(iii) of the Additional Protocol are known and are presently of great benefit to operations areas, this is only one aspect of its work. SIAL's ability to identify and analyze historical satellite imagery data has the advantage of permitting operations to take a more in depth view of a particular area of interest's (AOI) development, and thus may permit operations to confirm or refute specific assertions relating to the AOI's function or abilities. These assertions may originate in-house or may be open source reports the agency feels it is obligated to explore. SIAL's mission is unique in the world of imagery analysis. Its aim is to support all operations areas equally and in doing so it must maintain global focus. The task is tremendous, but the resultant coverage and concentration of unique expertise will allow SIAL to develop and provide operations with datasets that can be exploited in standalone mode or be incorporated into new cutting edge tools to be developed in SGIT. At present SIAL relies on two remote sensors, IKONOS-2 and EROS-AI, for present high- resolution imagery data and is using numerous sources for historical, pre 1999, data. A multiplicity of sources for high-resolution data is very important to SIAL, but is something that it cannot influence. It is hoped that the planned launch of two new sensors by Summer 2002 will be successful and will offer greater flexibility for image collection
Kaula, William M
The main purpose of this classic text is to demonstrate how Newtonian gravitational theory and Euclidean geometry can be used and developed in the earth's environment. The second is to collect and explain some of the mathematical techniques developed for measuring the earth by satellite.Book chapters include discussions of the earth's gravitational field, with special emphasis on spherical harmonies and the potential of the ellipsoid; matrices and orbital geometry; elliptic motion, linear perturbations, resonance, and other aspects of satellite orbit dynamics; the geometry of satellite obser
Artz, T.; Nothnagel, A.; La Porta, L.
For a consistent realization of a Global Geodetic Observing System (GGOS), a proper tie between the individual global reference systems used in the analysis of space-geodetic observations is a prerequisite. For instance, the link between the terrestrial, the celestial and the dynamic reference system of artificial Earth orbiters may be realized by Very Long O Baseline Interferometry (VLBI) observations of one or several satellites. In the preparation phase for a dedicated satellite mission, one option to realize this is using a geostationary (GEO) satellite emitting a radio signal in X-Band and/or S-Band and, thus, imitating a quasar. In this way, the GEO satellite can be observed by VLBI together with nearby quasars and the GEO orbit can, thus, be determined in a celestial reference frame. If the GEO satellite is, e.g., also equipped with a GNSS-type transmitter, a further tie between GNSS and VLBI may be realized. In this paper, a concept for the generation of a radio signal is shown. Furthermore, simulation studies for estimating the GEO position are presented with a GEO satellite included in the VLBI schedule. VLBI group delay observations are then simulated for the quasars as well as for the GEO satellite. The analysis of the simulated observations shows that constant orbit changes are adequately absorbed by estimated orbit parameters. Furthermore, the post-fit residuals are comparable to those from real VLBI sessions.
Tobehn, C.; Penné, B.; Rathje, R.; Weigl, A.; Gorecki, Ch.; Michalik, H.
The high costs to develop, launch and maintain a satellite network makes protecting the assets imperative. Attacks may be passive such as eavesdropping on the payload data. More serious threat are active attacks that try to gain control of the satellite, which may lead to the total lost of the satellite asset. To counter these threats, new satellite and ground systems are using cryptographic technologies to provide a range of services: confidentiality, entity & message authentication, and data integrity. Additionally, key management cryptographic services are required to support these services. This paper describes the key points of current satellite control and operations, that are authentication of the access to the satellite TMTC link and encryption of security relevant TM/TC data. For payload data management the key points are multi-user ground station access and high data rates both requiring frequent updates and uploads of keys with the corresponding key management methods. For secure satellite management authentication & key negotiation algorithms as HMAC-RIPEMD160, EC- DSA and EC-DH are used. Encryption of data uses algorithms as IDEA, AES, Triple-DES, or other. A channel coding and encryption unit for payload data provides download data rates up to Nx250 Mbps. The presented concepts are based on our experience and heritage of the security systems for all German MOD satellite projects (SATCOMBw2, SAR-Lupe multi- satellite system and German-French SAR-Lupe-Helios- II systems inter-operability) as well as for further international (KOMPSAT-II Payload data link system) and ESA activities (TMTC security and GMES).
Satellites are increasingly used for global communications, as well as for radio and television transmissions. With the growth of mobile communications, and of digital technology, the use of satellite systems is set to expand substantially and already all students of electronics or communications engineering must study the subject.This book steers a middle path between offering a basic understanding of the process of communication by satellite and the methodology used; and the extensive mathematical analysis normally adopted in similar texts. It presents the basic concepts, using as mu
Gehrels, T.; Drummond, J.D.; Levenson, N.A.
The absence of satellites within 0.1-7.0 arcmin of minor planets noted in the present CCD imaging survey is judged consistent with previous theoretical studies of collisions in which it is held that satellites would have to be larger than about 30 km in order to be collisionally stable. In view of tidal stability, the only main belt asteroid satellites which could conceivably possess stability over eons are near-contact binaries. Any recent collisional debris would be chaotic and collisionally unstable. 15 references
Mehta, Piyush Mukesh
The United States depends heavily on its space infrastructure for a vast number of commercial and military applications. Space Situational Awareness (SSA) and Threat Assessment require maintaining accurate knowledge of the orbits of resident space objects (RSOs) and the associated uncertainties. Atmospheric drag is the largest source of uncertainty for low-perigee RSOs. The uncertainty stems from inaccurate modeling of neutral atmospheric mass density and inaccurate modeling of the interaction between the atmosphere and the RSO. In order to reduce the uncertainty in drag modeling, both atmospheric density and drag coefficient (CD) models need to be improved. Early atmospheric density models were developed from orbital drag data or observations of a few early compact satellites. To simplify calculations, densities derived from orbit data used a fixed CD value of 2.2 measured in a laboratory using clean surfaces. Measurements from pressure gauges obtained in the early 1990s have confirmed the adsorption of atomic oxygen on satellite surfaces. The varying levels of adsorbed oxygen along with the constantly changing atmospheric conditions cause large variations in CD with altitude and along the orbit of the satellite. Therefore, the use of a fixed CD in early development has resulted in large biases in atmospheric density models. A technique for generating corrections to empirical density models using precision orbit ephemerides (POE) as measurements in an optimal orbit determination process was recently developed. The process generates simultaneous corrections to the atmospheric density and ballistic coefficient (BC) by modeling the corrections as statistical exponentially decaying Gauss-Markov processes. The technique has been successfully implemented in generating density corrections using the CHAMP and GRACE satellites. This work examines the effectiveness, specifically the transfer of density models errors into BC estimates, of the technique using the CHAMP and
Ondo, Tadanori; Nakamura, Yoshikatsu; Watanabe, Shigeaki; Murakami, Toshimitsu
On the basis of the VLF (50 Hz -- 30 kHz) electric field data from the satellite ISIS, the following works carried out in The Radio Research Laboratories are described: deuteron whistler and whistler duct, detection of plasmapause by LHR hiss, and the origin of 5 kHz hiss at low/middle latitudes. The deuteron whistlers are observable distinctly only at low latitude because of gyro-frequency and the frequency resolution of spectral analyzers. Whistler echo occurs when a whistler moves back and forth through a duct along the line of magnetic force, so it is considered that the ISIS satellite crosses the duct. The variation in ion composition around plasmapause obtained through LHR hiss is explainable by the plasamapause position and the magnetic storm effect on the plasamapause. Concerning the narrow band hiss of 5 kHz +- 1.0 kHz frequently observed on the ground at low/middle latitudes, it may occur around plasmapause, propagate through the ionosphere and then to the ground in waveguide mode, or otherwise, it may occur above the ionosphere and then propagate directly to the ground penetrating through the ionosphere. (J.P.N.)
Lowry, Peter A.
This paper depicts the Advanced Communication Technology Satellite (ACTS) system as a global central office switch. The ground portion of the system is the collection of earth stations or T1-VSAT's (T1 very small aperture terminals). The control software for the T1-VSAT's resides in a single CPU. The software consists of two modules, the modem manager and the call manager. The modem manager (MM) controls the RF modem portion of the T1-VSAT. It processes the orderwires from the satellite or from signaling generated by the call manager (CM). The CM controls the Recom Laboratories MSPs by receiving signaling messages from the stacked MSP shelves ro units and sending appropriate setup commands to them. There are two methods used to setup and process calls in the CM; first by dialing up a circuit using a standard telephone handset or, secondly by using an external processor connected to the CPU's second COM port, by sending and receiving signaling orderwires. It is the use of the external processor which permits the ISDN (Integrated Services Digital Network) Signaling Processor to implement ISDN calls. In August 1993, the initial testing of the ISDN Signaling Processor was carried out at ACTS System Test at Lockheed Marietta, Princeton, NJ using the spacecraft in its test configuration on the ground.
Williams, M.; Lunsford, A.; Ellis, D.; Robinson, J.; Coronado, P.; Campbell, W.
In 1990, a joint effort of two U.S. federal agencies, NASA Goddard Space Flight Center (GSFC) and the Patuxent Wildlife Research Center, began. We initially joined forces in a project that used satellite telemetry to discover the winter home of a tiny dwindling population of Siberian Cranes. Since then several projects have emerged, and a web site was created to follow some of these activities. This web site is called the Satellite Tracking of Threatened Species and its location is http://sdcd.gsfc.nasa.gov/ISTO/satellite_tracking. It describes the overall program, and links you to three subsections that describe the projects in more detail: Satellite Direct Readout, Birdtracks, and Birdworld.
Forrest, J. R.
A review is presented of the current television broadcasting situation in European countries, which involves a varied mix of terrestrial VHF or UHF systems and cable networks. A small market has emerged in Europe for receivers using the low-power telecommunications satellite transmission between the program providers and cable network companies. This is expected to change with the launch of medium-power pan-European telecommunication satellites (e.g. ASTRA, EUTELSAT II), which are now directly addressing the market of home reception. DBS (direct broadcast satellite) in the UK, using the D-MAC transmission standard, will offer three additional television channels, data broadcasting services, and a planned evolution to compatible forms of wide-screen, high-definition television. Comments are given on receiver and conditional access system standardization. Some views are expressed on satellite broadcasting as part of an overall broadcasting framework for the future.
The design approach used and the experience gained in the building of four small satellite payloads is explained. Specific recommendations are made and the lessons learned on the SAMPEX program are detailed.
National Oceanic and Atmospheric Administration, Department of Commerce — Sea turtles captured in various fishing gear (pound nets, long haul seines, gill nets) were outfitted with satellite transmitters so that their movements, migratory...
Garland, P. J.; Osborne, F. J.; Streibl, I.
The paper introduces two potential uses for new space hardware to permit enhanced levels of signal handling and switching in satellite communication service for Canada. One application involves increased private-sector services in the Ku band; the second supports new personal/mobile services by employing higher levels of handling and switching in the Ka band. First-generation satellite regeneration and switching experiments involving the NASA/ACTS spacecraft are described, where the Ka band and switching satellite network problems are emphasized. Second-generation satellite development is outlined based on demand trends for more packet-based switching, low-cost earth stations, and closed user groups. A demonstration mission for new Ka- and Ku-band technologies is proposed, including the payload configuration. The half ANIK E payload is shown to meet the demonstration objectives, and projected to maintain a fully operational payload for at least 10 years.
Sankar, Hollis C.
Discusses the need for, and the development, use, and future trends of, the University of the West Indies Distance Teaching Experiment, which utilizes telephone and communications satellite technology teleconferencing to extend educational opportunities to the peoples of the Caribbean. (MBR)
Fraser, D. O.
A discussion which contends that there is merit in not gearing satellite systems solely to educational broadcasting and that they should be designed for general communication, including telephony and television entertainment. (Author/HB)
Structure in the Uranian ring system as observed in recent occultations may contain indirect evidence for the existence of undiscovered satellites. Using the Alfven and Arrhenius (1975, 1976) scenario for the formation of planetary systems, the orbital radii of up to nine hypothetical satellites interior to Miranda are computed. These calculations should provide interesting comparisons when the results from the Voyager 2 encounter with Uranus are made public. 15 refs., 1 fig., 1 tab
National Oceanic and Atmospheric Administration, Department of Commerce — Shelf-wide Research Vessel Surveys are conducted 4-8 times per year over the continental shelf from Cape Hatteras, North Carolina to Cape Sable, Nova Scotia, using...
on the effect of environmental characteristics upon the encrusting calcareous-tube-making polychaete worm Hydroides dianthus has been begun, and it is...B. eb!Lineus. In spring 1978, work uas initiated on rearing the larvae of the calcareous encrusting tube worm Hydroides dianthus . Preliminary...larvae belonging to the coastal species, Balanus amphitrite and Hydroides dianthus and the estuarine barnacle, BaZanus ebur-neus. Some of the difficulties
Jones, J. H.
The question of whether the Earth ever passed through a magma ocean stage is of considerable interest. Geochemical evidence strongly suggests that the Moon had a magma ocean and the evidence is mounting that the same was true for Mars. Analyses of martian (SNC) meteorites have yielded insights into the differentiation history of Mars, and consequently, it is interesting to compare that planet to the Earth. Three primary features of Mars contrast strongly to those of the Earth: (i) the extremely ancient ages of the martian core, mantle, and crust (about 4.55 b.y.); (ii) the highly depleted nature of the martian mantle; and (iii) the extreme ranges of Nd isotopic compositions that arise within the crust and depleted mantle. The easiest way to explain the ages and diverse isotopic compositions of martian basalts is to postulate that Mars had an early magma ocean. Cumulates of this magma ocean were later remelted to form the SNC meteorite suite and some of these melts assimilated crustal materials enriched in incompatible elements. The REE pattern of the crust assimilated by these SNC magmas was LREE enriched. If this pattern is typical of the crust as a whole, the martian crust is probably similar in composition to melts generated by small degrees of partial melting (about 5%) of a primitive source. Higher degrees of partial melting would cause the crustal LREE pattern to be essentially flat. In the context of a magma ocean model, where large degrees of partial melting presumably prevailed, the crust would have to be dominated by late-stage, LREE-enriched residual liquids. Regardless of the exact physical setting, Nd and W isotopic evidence indicates that martian geochemical reservoirs must have formed early and that they have not been efficiently remixed since. The important point is that in both the Moon and Mars we see evidence of a magma ocean phase and that we recognize it as such. Several lines of theoretical inference point to an early Earth that was also hot and, perhaps, mostly molten. The Giant Impact hypothesis for the origin of the Moon offers a tremendous input of thermal energy and the same could be true for core formation. And current solar system models favor the formation of a limited number of large (about 1000 km) planetesimals that, upon accreting to Earth, would cause great heating, being lesser versions of the Giant Impact. Several lines of geochemical evidence do not favor this hot early Earth scenario. (i) Terrestrial man-tle xenoliths are sometimes nearly chondritic in their major element compositions, suggesting that these rocks have never been much molten. Large degrees of partial melting probably promote differentiation rather than homogenization. (ii) Unlike the case of Mars, the continental crust probably did not form as a highly fractionated residual liquid from a magma ocean (about 99% crystallization), but, rather, formed in multiple steps. [The simplest model for the formation of continental crust is complicated: (a) about 10% melting of a primitive mantle, making basalt; (b) hydrothermal alteration of that basalt, converting it to greenstone; and (c) 10% partial melting of that greenstone, producing tonalite.] This model is reinforced by the recent observation from old (about 4.1 b.y.) zircons that the early crust formed from an undepleted mantle having a chondritic Lu/Hf ratio. (iii) If the mantle were once differentiated by a magma ocean, the mantle xenolith suite requires that it subsequently be homogenized. The Os isotopic compositions of fertile spinel lherzolites place constraints on the timing of that homogenization. The Os isotopic composition of spinel lherzolites approaches that of chondrites and correlates with elements such as Lu and Al. As Lu and Al concentrations approach those of the primitive mantle, Os isotopic compositions approach chondritic. The Re and Os in these xenoliths were probably added as a late veneer. Thus, the mantle that received the late veneer must have been nearly chondritic in terms of its major elements (excluding Fe). If the mantle that the veneer was mixed into was not al-ready homogenized, then Os isotopes should not correlate with incompatible elements such as Al. Consequently, either early differentiation of the mantle did not occur or the homogenization of this differentiation must have occurred before the late veneer was added. The timing of the late veneer is itself uncertain but presumably postdated core formation at about 4.45 b.y. and did not postdate the 3.8-3.9 b.y. late bombardment of the Moon. This timing based on siderophile elements is consistent with the Hf isotopic evidence cited above. If the Earth, Moon and Mars had magma oceans, the Earth subsequently rehomogenized whereas the Moon and Mars did not. The simplest solution to this observation is that homogenization of igneous differentiates was never necessary on Earth, either because the hypothetical magma ocean never occurred or because this event did not produce mantle differentiation.
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in the first two shallow seas are driven by surface densification following evaporation that in the latter is largely influenced by freshwater discharge from Irrawaddy and inflows across the Andaman Ridge from east Bay of Bengal. Biological productivity...
World class health care for common man at low affordable cost: anywhere, anytime The project envisages to set up a national network of satellite Medical centers. Each SMC would be manned by doctors, nurses and technicians, six doctors, six nurses, six technicians would be required to provide 24 hour cover, each SMC would operate 24 hours x 7 days. It would be equipped with the Digital telemedicine devices for capturing clinical patient information and investigations in the form of voice, images and data and create an audiovisual text file - a virtual Digital patient. Through the broad band connectivity the virtual patient can be sent to the central hub, manned by specialists, specialists from several specialists sitting together can view the virtual patient and provide a specialized opinion, they can see the virtual patient, see the examination on line through video conference or even PCs, talk to the patient and the doctor at the SMC and controlle capturing of information during examination and investigations of the patient at the SMC - thus creating a virtual Digital consultant at the SMC. Central hub shall be connected to the doctors and consultants in remote locations or tertiary care hospitals any where in the world, thus creating a virtual hub the hierarchical system shall provide upgradation of knowledge to thedoctors in central hub and smc and thus continued medical education and benefit the patient thru the world class treatment in the smc located at his door step. SMC shall be set up by franchisee who shall get safe business opportunity with high returns, patients shall get Low cost user friendly worldclass health care anywhere anytime, Doctors can get better meaningful selfemplyment with better earnings, flexibility of working time and place. SMC shall provide a wide variety of services from primary care to world class Global consultation for difficult patients.
Borges, A.; Cerezo, F.; Fernandez, M.; Lomba, J.; Lopez, M.; Moreno, J.; Neira, A.; Quintana, C.; Torres, J.; Trigo, R.; Urena, J.; Vega, E.; Vez, E.
The Spanish Ministry of Industry, Tourism and Trade (MITyC) and the Ministry of Defense (MoD) signed an agreement in 2007 for the development of a "Spanish Earth Observation Satellite System" based, in first instance, on two satellites: a high resolution optical satellite, called SEOSAT/Ingenio, and a radar satellite based on SAR technology, called SEOSAR/Paz. SEOSAT/Ingenio is managed by MITyC through the Centre for the Development of Industrial Technology (CDTI), with technical and contractual support from the European Space Agency (ESA). HISDESA T together with the Spanish Instituto Nacional de Técnica Aeroespacial (INTA, National Institute for Aerospace Technology) will be responsible for the in-orbit operation and the commercial operation of both satellites, and for the technical management of SEOSAR/Paz on behalf of the MoD. In both cases EADS CASA Espacio (ECE) is the prime contractor leading the industrial consortia. The ground segment development will be assigned to a Spanish consortium. This system is the most important contribution of Spain to the European Programme Global Monitoring for Environment and Security, GMES. This paper presents the Spanish Earth Observation Satellite System focusing on SEOSA T/Ingenio Programme and with special emphasis in the potential contribution to the ESA Third Party Missions Programme and to the Global Monitoring for Environment and Security initiative (GMES) Data Access.
Federal Laboratory Consortium — Description/History: Chemistry laboratoryThe Advanced Chemistry Laboratory (ACL) is a unique facility designed for working with the most super toxic compounds known...
Federal Laboratory Consortium — The Lincoln Laboratory Grid (LLGrid) is an interactive, on-demand parallel computing system that uses a large computing cluster to enable Laboratory researchers to...
Federal Laboratory Consortium — The Gun Dynamics Laboratory is a research multi-task facility, which includes two firing bays, a high bay area and a second floor laboratory space. The high bay area...
Federal Laboratory Consortium — The NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory is a NASA funded facility, delivering heavy ion beams to a target area where scientists...
Federal Laboratory Consortium — Program CapabilitiesDEN-DO Laboratory is a multi-functional laboratory capable of analyzing most chemical analytes and pathogenic/non-pathogenic microorganisms found...
Hurley, Michael; Duffey, Timothy; Huffine, Christopher; Weldy, Ken; Cleveland, Jeff; Hauser, Joe
The Secretary of Defense’s Office of Force Transformation (OFT) is currently undertaking an initiative to develop a low-cost, responsive, operationally relevant space capability using small satellites. The Naval Research Laboratory (NRL) is tasked to be program manger for this initiative, which seeks to make space assets and capabilities available to operational users. TacSat-1 is the first in a series of small satellites that will result in rapid, tailored, and operationally relevant experim...
Artificial satellites are easily observed most nights when the weather is fine. The website called "Heavens Above" at www.heavens-above.com will help locate these satellites flying over one's location. It also includes how bright they will appear. The direction of travel of each satellite in the night sky also indicates the type of satellite. For…
Fabiansen, C.; Knudsen, J.D.; Lebech, A.M.
Brucellosis is a rare disease in Denmark. We describe one case of laboratory-acquired brucellosis from an index patient to a laboratory technician following exposure to an infected blood culture in a clinical microbiology laboratory Udgivelsesdato: 2008/6/9......Brucellosis is a rare disease in Denmark. We describe one case of laboratory-acquired brucellosis from an index patient to a laboratory technician following exposure to an infected blood culture in a clinical microbiology laboratory Udgivelsesdato: 2008/6/9...
Douglas, Dennis Michael
Geosynchronous (GEO) satellites are essential for modern communication networks. If communication to a GEO satellite is lost and a malfunction occurs upon orbit insertion such as a solar panel not deploying there is no direct way to observe it from Earth. Due to the GEO orbit distance of ~36,000 km from Earth's surface, the Rayleigh criteria dictates that a 14 m telescope is required to conventionally image a satellite with spatial resolution down to 1 m using visible light. Furthermore, a telescope larger than 30 m is required under ideal conditions to obtain spatial resolution down to 0.4 m. This dissertation evaluates a method for obtaining high spatial resolution images of GEO satellites from an Earth based system by measuring the irradiance distribution on the ground resulting from the occultation of the satellite passing in front of a star. The representative size of a GEO satellite combined with the orbital distance results in the ground shadow being consistent with a Fresnel diffraction pattern when observed at visible wavelengths. A measurement of the ground shadow irradiance is used as an amplitude constraint in a Gerchberg-Saxton phase retrieval algorithm that produces a reconstruction of the satellite's 2D transmission function which is analogous to a reverse contrast image of the satellite. The advantage of shadow imaging is that a terrestrial based redundant set of linearly distributed inexpensive small telescopes, each coupled to high speed detectors, is a more effective resolved imaging system for GEO satellites than a very large telescope under ideal conditions. Modeling and simulation efforts indicate sub-meter spatial resolution can be readily achieved using collection apertures of less than 1 meter in diameter. A mathematical basis is established for the treatment of the physical phenomena involved in the shadow imaging process. This includes the source star brightness and angular extent, and the diffraction of starlight from the satellite
Federal Laboratory Consortium — NIST's PV characterization laboratory is used to measure the electrical performance and opto-electronic properties of solar cells and modules. This facility consists...
Federal Laboratory Consortium — The ARDEC Rapid Prototyping (RP) Laboratory was established in December 1992 to provide low cost RP capabilities to the ARDEC engineering community. The Stratasys,...
Federal Laboratory Consortium — The TVA Central Laboratories Services is a comprehensive technical support center, offering you a complete range of scientific, engineering, and technical services....
Federal Laboratory Consortium — For more than 60 years, Sandia has delivered essential science and technology to resolve the nation's most challenging security issues.Sandia National Laboratories...
Federal Laboratory Consortium — The Wireless Emulation Laboratory (WEL) is a researchtest bed used to investigate fundamental issues in networkscience. It is a research infrastructure that emulates...
Federal Laboratory Consortium — This laboratory develops screening assays, tests and modifies biosensor equipment, and optimizes food safety testing protocols for the military and civilian sector...
Federal Laboratory Consortium — The Embedded Processor Laboratory provides the means to design, develop, fabricate, and test embedded computers for missile guidance electronics systems in support...
Federal Laboratory Consortium — FUNCTION: Supports the development of prototype deployment platform vehicles for offboard countermeasure systems.DESCRIPTION: The Vehicle Development Laboratory is...
Federal Laboratory Consortium — This laboratory contains an electro-magnetic worldwide data collection and field measurement capability in the area of acoustic technology. Outfitted by NASA Langley...
Federal Laboratory Consortium — This laboratory conducts basic and applied human research studies to characterize cognitive performance as influenced by militarily-relevant contextual and physical...
Federal Laboratory Consortium — The Space Weather Computational Laboratory is a Unix and PC based modeling and simulation facility devoted to research analysis of naturally occurring electrically...
Federal Laboratory Consortium — The Atmospheric Measurements Laboratory (AML) is one of the nation's leading research facilities for understanding aerosols, clouds, and their interactions. The AML...
Federal Laboratory Consortium — The purpose of the Composites Characterization Laboratory is to investigate new and/or modified matrix materials and fibers for advanced composite applications both...
Federal Laboratory Consortium — The Microgravity Emissions Laboratory (MEL) utilizes a low-frequency acceleration measurement system for the characterization of rigid body inertial forces generated...
Federal Laboratory Consortium — The Semiconductor Laser Measurements Laboratory is equipped to investigate and characterize the lasing properties of semiconductor diode lasers. Lasing features such...
Federal Laboratory Consortium — NETL’s Fuels Processing Laboratory in Morgantown, WV, provides researchers with the equipment they need to thoroughly explore the catalytic issues associated with...
Federal Laboratory Consortium — The Advanced Manufacturing Laboratory at the University of Maryland provides the state of the art facilities for realizing next generation products and educating the...
Federal Laboratory Consortium — The Virtual Training Devices (VTD) Laboratory at the Life Cycle Software Engineering Center, Picatinny Arsenal, provides a software testing and support environment...
Federal Laboratory Consortium — The Intelligent Optics Laboratory supports sophisticated investigations on adaptive and nonlinear optics; advancedimaging and image processing; ground-to-ground and...
Federal Laboratory Consortium — This laboratory contains equipment that performs a broad array of microbiological analyses for pathogenic and spoilage microorganisms. It performs challenge studies...
Pritchard, Jack; Braker, Clifton
Pritchard discusses the opportunities for applied learning afforded by laboratories. Braker describes the evaluation of cognitive, affective, and psychomotor skills in the agricultural mechanics laboratory. (SK)
Federal Laboratory Consortium — This facility provides office space for industry researchers, experimental laboratories, computer facilities for analytical work, and space for assembling components...
Federal Laboratory Consortium — FUNCTION: To process, store, and disseminate geospatial data to the Department of Defense and other Federal agencies.DESCRIPTION: The Geospatial Services Laboratory...
Federal Laboratory Consortium — At NETL’s Thermogravimetric Analysis Laboratory in Morgantown, WV, researchers study how chemical looping combustion (CLC) can be applied to fossil energy systems....
Federal Laboratory Consortium — The Research Combustion Laboratory (RCL) develops aerospace propulsion technology by performing tests on propulsion components and materials. Altitudes up to 137,000...
Federal Laboratory Consortium — The Combustion Research Laboratory facilitates the development of new combustion systems or improves the operation of existing systems to meet the Army's mission for...
Federal Laboratory Consortium — Purpose: The mission of the Coatings and Corrosion Laboratory is to develop and analyze the effectiveness of innovative coatings test procedures while evaluating the...
Federal Laboratory Consortium — Current research in the Laboratory of Chemical Physics is primarily concerned with experimental, theoretical, and computational problems in the structure, dynamics,...
Federal Laboratory Consortium — The Optical Remote Sensing Laboratory deploys rugged, cutting-edge electro-optical instrumentation for the collection of various event signatures, with expertise in...
Federal Laboratory Consortium — The Tactical Systems Integration Laboratory is used to design and integrate computer hardware and software and related electronic subsystems for tactical vehicles....
Federal Laboratory Consortium — As part of the Electrical and Computer Engineering Department and The Institute for System Research, the Neural Systems Laboratory studies the functionality of the...
Federal Laboratory Consortium — The Environmental Microbiology Laboratory, located in Bldg. 644 provides a dual-gas respirometer for measurement of oxygen consumption and carbon dioxide evolution...
Kudak, V. I.; Epishev, V. P.; Perig, V. M.; Neybauer, I. F.
We present the results of photometric observations of the TOPEX/Poseidon satellite performed during 2008-2016. The satellite become space debris after a failure in January, 2006, in a low Earth orbit. In the Laboratory of Space Research of Uzhhorod National University 73 light curves of the spacecraft were obtained. Standardization of photometric light curves is briefly explained. We have calculated the color indices of reflecting surfaces and the spin rate change. The general tendency of the latter is described by an exponential decay function. The satellite spin periods based on 126 light curves (including 53 light curves from the MMT-9 project operating since 2014) were taken into account. In 2016 the period of its own rotation reached its minimum of 10.6 s. A method to derive the direction of the spin axis of an artificial satellite and the angles of the light scattered by its surface has been developed in the Laboratory of Space Research of Uzhhorod National University. We briefly describe the "Orientation" program used for these purposes. The orientation of the TOPEX/Poseidon satellite in mid-2016 is given. The angle of precession β = 45°-50° and period of precession P pr = 141.5 s have been defined. The reasons for the identified nature of the satellite's own rotation have been found. They amount to the perturbation caused by a deviation of the Earth gravity field from a central-symmetric shape and the presence of moving parts on the satellite.
The elements (principles) of quality assurance can be applied to the operation of the analytical chemistry laboratory to provide an effective tool for indicating the competence of the laboratory and for helping to upgrade competence if necessary. When used, those elements establish the planned and systematic actions necessary to provide adequate confidence in each analytical result reported by the laboratory (the definition of laboratory quality assurance). The elements, as used at the Hanford Engineering Development Laboratory (HEDL), are discussed and they are qualification of analysts, written methods, sample receiving and storage, quality control, audit, and documentation. To establish a laboratory quality assurance program, a laboratory QA program plan is prepared to specify how the elements are to be implemented into laboratory operation. Benefits that can be obtained from using laboratory quality assurance are given. Experience at HEDL has shown that laboratory quality assurance is not a burden, but it is a useful and valuable tool for the analytical chemistry laboratory
Full Text Available The SatBałtyk (Satellite Monitoring of the Baltic Sea Environment project is being realized in Poland by the SatBałtyk Scientific Consortium, specifically appointed for this purpose, which associates four scientific institutions: the Institute of Oceanology PAN in Sopot - coordinator of the project, the University of Gdańsk (Institute of Oceanography, the Pomeranian Academy in Słupsk (Institute of Physics and the University of Szczecin (Institute of Marine Sciences. The project is aiming to prepare a technical infrastructure and set in motion operational procedures for the satellite monitoring of the Baltic Sea ecosystem. The main sources of input data for this system will be the results of systematic observations by metrological and environmental satellites such as TIROS N/NOAA, MSG (currently Meteosat 10, EOS/AQUA and Sentinel -1, 2, 3 (in the future. The system will deliver on a routine basis the variety of structural and functional properties of this sea, based on data provided by relevant satellites and supported by hydro-biological models. Among them: the solar radiation influx to the sea’s waters in various spectral intervals, energy balances of the short- and long-wave radiation at the Baltic Sea surface and in the upper layers of the atmosphere over the Baltic, sea surface temperature distribution, dynamic states of the water surface, concentrations of chlorophyll a and other phytoplankton pigments in the Baltic waters, spatial distributions of algal blooms, the occurrence of coastal upwelling events, and the characteristics of primary production of organic matter and photosynthetically released oxygen in the water and many others. The structure of the system and preliminary results will be presented.
The choice of the scientific payloads of the European Space Research Organization's (ESRO's) first generation of satellites is analyzed. Concentration is on those aspects of the decision process that involved more directly the scientific community and that emerged as major issues in the discussion of the Launching Program Advisory Committee (LPAC). The main theme was the growing competition between the various fields of space science within the progressive retrenching of the Organization's financial resources available for the satellite program. A general overview of the status of the program by the end of 1966 is presented. The choice of the first small satellites' payloads (ESRO 1 and 2, and HEOS-A) and the difficult definition of the TD satellite program are discussed. This part covers a time span going from early 1963 to the spring of 1966. In the second part, the narrative starts from the spring of 1967, when the decision to recommend a second HEOS-type satellite was taken, and then analyzes the complex situation determined by the crisis of the TD program in 1968, and the debates which eventually led to the abandonment of TD-2 and the start of the far less ambitious ESRO 5 project.
Veverka, J.; Thomas, P.; Johnson, T.V.; Matson, D.; Housen, K.
Both exogenic and endogenic effects have been proposed to explain the major observed characteristics of satellite surfaces. The current view is that the basic properties of most surfaces result from the intrinsic composition of a body and its geologic history. Exogenic effects have, however, played a role in modifying the appearance of nearly all surfaces. The most important exogenic effect is impact cratering, one manifestation of which is the production of micrometeoroid gardened regoliths on airless bodies. On large, silicate bodies the micrometeoroid bombardment can produce an optically mature, dark agglutinate-rich soil; the nature of regoliths on predominantly icy satellites remains uncertain. Direct accumulation of infalling material does not appear to play a major role in modifying most surfaces. Solar wind radiation effects have not altered greatly the optical properties of solar system objects; magnetospheric charged particles may have modified the optical properties of some outer planet satellites (e.g., sulfur ion bombardment in the case of some of the satellites of Jupiter). Other effects, such as aeolian and liquid/solid chemical weathering, may be important on satellites with atmospheres like Titan and Triton
The question of how to launch small satellites has been solved over the years by the larger launchers offering small satellites the possibility of piggy-backing. Specific fixtures have been developed and commercialized: Arianespace developed the ASAP interface, the USAF studied ESPA, NASA has promoted Shuttle launch possibilities, Russian authorities and companies have been able to find solutions with many different launchers... It is fair to say that most launcher suppliers have worked hard and finally often been able to find solutions to launch most small satellites into orbit. It is also true, however, that most of these small satellites were technology demonstration missions capable of accepting a wide range of orbit and launch characteristics: orbit altitude and inclination, launch date, etc. In some cases the small satellite missions required a well-defined type of orbit and have therefore been obliged to hire a small launcher on which they were the prime passenger. In our paper we would like to propose an additional solution to all these possibilities: launchers could plan well in advance (for example about 3 years), trips to precisely defined orbits to allow potential passengers to organize themselves and be ready on the D-Day. On the scheduled date the chartered launcher goes to the stated orbit while on another date, another chartered launcher goes to another orbit. The idea is to organize departures for space like trains or airplanes leaving on known schedules for known destinations.
Giordani, Lorenzo; Parisi, Alice; Le Grand, Fabien
Adult skeletal muscle is endowed with regenerative potential through partially recapitulating the embryonic developmental program. Upon acute injury or in pathological conditions, quiescent muscle-resident stem cells, called satellite cells, become activated and give rise to myogenic progenitors that massively proliferate, differentiate, and fuse to form new myofibers and restore tissue functionality. In addition, a proportion of activated cells returns back to quiescence and replenish the pool of satellite cells in order to maintain the ability of skeletal muscle tissue to repair. Self-renewal is the process by which stem cells divide to make more stem cells to maintain the stem cell population throughout life. This process is controlled by cell-intrinsic transcription factors regulated by cell-extrinsic signals from the niche and the microenvironment. This chapter provides an overview about the general aspects of satellite cell biology and focuses on the cellular and molecular aspects of satellite cell self-renewal. To date, we are still far from understanding how a very small proportion of the satellite cell progeny maintain their stem cell identity when most of their siblings progress through the myogenic program to construct myofibers. © 2018 Elsevier Inc. All rights reserved.
Garrido-Ramos, Manuel A
Satellite DNA represents one of the most fascinating parts of the repetitive fraction of the eukaryotic genome. Since the discovery of highly repetitive tandem DNA in the 1960s, a lot of literature has extensively covered various topics related to the structure, organization, function, and evolution of such sequences. Today, with the advent of genomic tools, the study of satellite DNA has regained a great interest. Thus, Next-Generation Sequencing (NGS), together with high-throughput in silico analysis of the information contained in NGS reads, has revolutionized the analysis of the repetitive fraction of the eukaryotic genomes. The whole of the historical and current approaches to the topic gives us a broad view of the function and evolution of satellite DNA and its role in chromosomal evolution. Currently, we have extensive information on the molecular, chromosomal, biological, and population factors that affect the evolutionary fate of satellite DNA, knowledge that gives rise to a series of hypotheses that get on well with each other about the origin, spreading, and evolution of satellite DNA. In this paper, I review these hypotheses from a methodological, conceptual, and historical perspective and frame them in the context of chromosomal organization and evolution.
Little, Frank E.
Space Solar Power (SSP) applies broadly to the use of solar power for space related applications. The thrust of the NASA SSP initiative is to develop concepts and demonstrate technology for applying space solar power to NASA missions. Providing power from satellites in space via wireless transmission to a receiving station either on earth, another celestial body or a second satellite is one goal of the SSP initiative. The sandwich design is a satellite design in which the microwave transmitting array is the front face of a thin disk and the back of the disk is populated with solar cells, with the microwave electronics in between. The transmitter remains aimed at the earth in geostationary orbit while a system of mirrors directs sunlight to the photovoltaic cells, regardless of the satellite's orientation to the sun. The primary advantage of the sandwich design is it eliminates the need for a massive and complex electric power management and distribution system for the satellite. However, it requires a complex system for focusing sunlight onto the photovoltaic cells. In addition, positioning the photovoltaic array directly behind the transmitting array power conversion electronics will create a thermal management challenge. This project focused on developing designs and finding emerging technology to meet the challenges of solar tracking, a concentrating mirror system including materials and coatings, improved photovoltaic materials and thermal management.
Laboratory diagnosis is auxillary medical discipline studying specific laboratory symptoms of diseases, revealed by investigations of materials taken from patients. The structure of laboratory servie in our country and abroad, items of laboratory investigations, organizational principles are described. Attention is being given to the cost of analyses, the amount of conducted investigations, methods of result presentation, problems of accuracy, quality control and information content
Isajenko, K.A.; Lipinski, P.
The article presents the Mobile Spectrometric Laboratory used by Central Laboratory for Radiological Protection since year 2000. The equipment installed in the Mobile Laboratory and its uses is described. The results of international exercises and intercalibrations, in which the Laboratory participated are presented. (author)
A computer system was developed allowing the control of nuclear physics experiments, and use of the results by means of graphical and conversational assemblies. This system which is made of two computers, one IBM-370/135 and one Telemecanique Electrique T1600, controls the conventional IBM peripherals and also the special ones made in the laboratory, such as data acquisition display and graphics units. The visual display is implemented by a scanning-type television, equipped with a light-pen. These units in themselves are universal, but their specifications were established to meet the requirements of nuclear physics experiments. The input-output channels of the two computers have been connected together by an interface, designed and implemented in the Laboratory. This interface allows the exchange of control signals and data (the data are changed from bytes into word and vice-versa). The T1600 controls the peripherals mentionned above according to the commands of the IBM370. Hence the T1600 has here the part of a satellite computer which allows conversation with the main computer and also insures the control of its special peripheral units [fr
Hosseinidehaj, Nedasadat; Malaney, Robert
In this work we analyze three quantum communication schemes for the generation of Gaussian entanglement between two ground stations. Communication occurs via a satellite over two independent atmospheric fading channels dominated by turbulence-induced beam wander. In our first scheme, the engineering complexity remains largely on the ground transceivers, with the satellite acting simply as a reflector. Although the channel state information of the two atmospheric channels remains unknown in this scheme, the Gaussian entanglement generation between the ground stations can still be determined. On the ground, distillation and Gaussification procedures can be applied, leading to a refined Gaussian entanglement generation rate between the ground stations. We compare the rates produced by this first scheme with two competing schemes in which quantum complexity is added to the satellite, thereby illustrating the tradeoff between space-based engineering complexity and the rate of ground-station entanglement generation.
Qualls, Garry D.; Ferebee, Melvin J., Jr.
A NASA-sponsored systems analysis designed to identify and recommend advanced subsystems and technologies specifically for a manned Sun-synchronous platform for satellite management is discussed. An overview of system design, manned and unmanned servicing facilities, and representative mission scenarios are given. Mission areas discussed include facility based satellite assembly, checkout, deployment, refueling, repair, and systems upgrade. The ferrying of materials and consumables to and from manufacturing platforms, deorbit, removal, repositioning, or salvage of satellites and debris, and crew rescue of any other manned vehicles are also examined. Impacted subsytems discussed include guidance navigation and control, propulsion, data management, power, thermal control, structures, life support, and radiation management. In addition, technology issues which would have significant impacts on the system design are discussed.
Jakhu, Ram S
Since the launch of UoSat-1 of the University of Surrey (United Kingdom) in 1981, small satellites proved regularly to be useful, beneficial, and cost-effective tools. Typical tasks cover education and workforce development, technology demonstration, verification and validation, scientific and engineering research as well as commercial applications. Today the launch masses range over almost three orders of magnitude starting at less than a kilogram up to a few hundred kilograms, with budgets of less than US$ 100.00 and up to millions within very short timeframes of sometimes less than two years. Therefore each category of small satellites provides specific challenges in design, development and operations. Small satellites offer great potentials to gain responsive, low-cost access to space within a short timeframe for institutions, companies, regions and countries beyond the traditional big players in the space arena. For these reasons (particularly the low cost of construction, launch and operation), small (m...
Ivancic, William D.; Griner, James H.; Dimond, Robert; Frantz, Brian D.; Kachmar, Brian; Shell, Dan
NASA Glenn Research Center has been working with industry, academia, and other government agencies in assessing commercial communications protocols for satellite and space-based applications. In addition, NASA Glenn has been developing and advocating new satellite-friendly modifications to existing communications protocol standards. This paper summarizes recent research into the applicability of various commercial standard protocols for use over satellite and space- based communications networks as well as expectations for future protocol development. It serves as a reference point from which the detailed work can be readily accessed. Areas that will be addressed include asynchronous-transfer-mode quality of service; completed and ongoing work of the Internet Engineering Task Force; data-link-layer protocol development for unidirectional link routing; and protocols for aeronautical applications, including mobile Internet protocol routing for wireless/mobile hosts and the aeronautical telecommunications network protocol.
Paulsen, Gøran; Mikkelsen, Ulla Ramer; Raastad, Truls
uncertain. The COX enzymes regulate satellite cell activity, as demonstrated in animal models; however the roles of the COX enzymes in human skeletal muscle need further investigation. We suggest using the term 'muscle damage' with care. Comparisons between studies and individuals must consider changes......-damaging exercise', primarily eccentric exercise. We review the evidence for the notion that the degree of muscle damage is related to the magnitude of the cytokine response. In the third and final section, we look at the satellite cell response to a single bout of eccentric exercise, as well as the role...... variation in individual responses to a given exercise should, however be expected. The link between cytokine and satellite cell responses and exercise-induced muscle damage is not so clear The systemic cytokine response may be linked more closely to the metabolic demands of exercise rather than muscle...
Since 1972, Landsat satellites have continuously acquired space-based images of the Earth’s land surface, providing data that serve as valuable resources for land use/land change research. The data are useful to a number of applications including forestry, agriculture, geology, regional planning, and education. Landsat is a joint effort of the U.S. Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA). NASA develops remote sensing instruments and the spacecraft, then launches and validates the performance of the instruments and satellites. The USGS then assumes ownership and operation of the satellites, in addition to managing all ground reception, data archiving, product generation, and data distribution. The result of this program is an unprecedented continuing record of natural and human-induced changes on the global landscape.
Samson, J.A.R.; Lee Eunmee; Chung, Y.
The production of specific Ar + satellite states has been studied with synchrotron radiation at wavelengths between 300 and 350 A with an effective energy resolution of 20 meV. The specific states studied were the ( 3 P)4p( 2 P 3/2 ), ( 1 D)4p( 2 F 7/2 ), and ( 1 D)4p( 2 P 1/2 ) states. The fluorescent radiation emitted from these excited ionic states was measured at 4766, 4611, and 4133 A by the use of narrow band interference filters. The variation of the fluorescence intensity was measured as a function of wavelength. This provided a measure of the relative cross section for production of the satellite states. Each satellite state was found to be completely dominated by autoionization of the neutral doubly excited states (3s 2 3p 4 )nl, n'l' found in this spectral region. (orig.)
Kupferman, S.L. (ed.)
This report covers the work of the Physical Oceanography and Water Column Geochemistry (POWCG) Studies Group of the Subseabed Disposal Project (SDP) from October 1984 to termination of the project in May 1986. The overview of the work includes an introduction, general descriptions of the activities, and a summary. Detailed discussions are included as appendices. During the period of this report the POWCG Studies Group held a meeting to develop a long-term research plan for the Nares Abyssal Plain, which was recently designated as a study area for the Environmental Study Group of the SDP. The POWCG Studies Group has also planned and participated in two interdisciplinary oceanographic missions to the Nares which have resulted in the acquisition of data and samples which can be used to begin to understand the workings of the ecosystem at the site, and for developing a preliminary site assessment. The papers in the appendices have been processed for inclusion in the Energy Data Base.
DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)
This project centers around the Strategic Petroleum Site (SPR) known as the West Hackberry salt dome which is located in southwestern Louisiana, and which is designed to store 241 million barrels of crude oil. Oil storage caverns are formed by injecting water into salt deposits, and pumping out the resulting brine. Studies described in this report were designed as follow-on studies to three months of pre-discharge characterization work, and include data collected during the first year of brine leaching operations. The objectives were to: (1) characterize the environment in terms of physical, chemical and biological attributes; (2) determine if significant adverse changes in ecosystem productivity and stability of the biological community are occurring as a result of brine discharge; and (3) determine the magnitude of any change observed. Contents of Volume II include: introduction; physical oceanography; estuarine hydrology and hydrography; analysis of discharge plume; and water and sediment quality.
This report covers the work of the Physical Oceanography and Water Column Geochemistry (POWCG) Studies Group of the Subseabed Disposal Project (SDP) from October 1984 to termination of the project in May 1986. The overview of the work includes an introduction, general descriptions of the activities, and a summary. Detailed discussions are included as appendices. During the period of this report the POWCG Studies Group held a meeting to develop a long-term research plan for the Nares Abyssal Plain, which was recently designated as a study area for the Environmental Study Group of the SDP. The POWCG Studies Group has also planned and participated in two interdisciplinary oceanographic missions to the Nares which have resulted in the acquisition of data and samples which can be used to begin to understand the workings of the ecosystem at the site, and for developing a preliminary site assessment. The papers in the appendices have been processed for inclusion in the Energy Data Base
Federal Laboratory Consortium — The Energy Materials Research Laboratory at the Savannah River National Laboratory (SRNL) creates a cross-disciplinary laboratory facility that lends itself to the...
The Northeast Fisheries Science Center's (NEFSC) Student Drifters Program is providing education opportunities for students of all ages. Using GPS-tracked ocean drifters, various educational institutions can provide students with hands-on experience in physical oceanography, engineering, and computer science. In building drifters many high school and undergraduate students may focus on drifter construction, sometimes designing their own drifter or attempting to improve current NEFSC models. While learning basic oceanography younger students can build drifters with the help of an educator and directions available on the studentdrifters.org website. Once drifters are deployed, often by a local mariner or oceanographic partner, drifter tracks can be visualised on maps provided at http://nefsc.noaa.gov/drifter. With the lesson plans available for those interested in computer science, students may download, process, and plot the drifter position data with basic Python code provided. Drifter tracks help students to visualize ocean currents, and also allow them to understand real particle tracking applications such as in search and rescue, oil spill dispersion, larval transport, and the movement of injured sea animals. Additionally, ocean circulation modelers can use student drifter paths to validate their models. The Student Drifters Program has worked with over 100 schools, several of them having deployed drifters on the West Coast. Funding for the program often comes from individual schools and small grants but in the future will preferably come from larger government grants. NSF, Sea-Grant, NOAA, and EPA are all possible sources of funding, especially with the support of multiple schools and large marine education associations. The Student Drifters Program is a unique resource for educators, students, and scientists alike.
Kolker, A.; Chu, P. Y.; Taylor, C.; Roberts, B. J.; Renfro, A. A.; Peyronnin, N.; Fitzpatrick, C.
While it has long been recognized that the Mississippi River is the largest source of freshwater, nutrients and sediments to the Gulf of Mexico, many questions remain unanswered about the impacts of the material on oceanography of the system. Here we report on the results of a regional synthesis study that examined how the Mississippi River and its delta influence the oceanography, ecology and the economy of the Gulf of Mexico. By employing a series of expert-opinion working groups, and using multi-dimensional numerical physical oceanographic models coupled to in-situ environmental data, this project is working to quantify how variability in discharge, meteorological forcings, and seasonal conditions influence the spatial distribution of the Mississippi River plume and its influence. Results collected to date indicate that the dimensions of the river plume are closely coupled to discharge, but in a non-linear fashion, that incorporates fluxes, flow distributions, offshore and meteorological forcings in the context of the local bathymetry. Ongoing research is using these human and numerical tools to help further elucidate the impacts of this river on the biogeochemistry of the region, and the distribution of key macrofauna. Further work by this team is examining how the delta's impacts on the ecology of the region, and the role that the delta plays as both a source of material for key offshore fauna, and a barrier to dispersal. This information is being used to help further the development of a research agenda for the northern Gulf of Mexico that will be useful through the mid-21st century.
Communication links via satellites are becoming available in Europe, both as part of the development of the telephone system and as special services aimed at data traffic. They offer the possibility of speeds between 50 kb/s and 2 Mb/s, without the problems and long term commitments of long distance land lines. Such links are provided by the PTT's as circuits which can be booked for variable periods, and have error rates which can be very low and well controlled. Problems in networking can arise from the satellite delay, particularly if errors occur in the local connections, and from the leased circuit and tariff philosophies of the PTT's. (Auth.)
Atwood, S.; Higton, G. H.; Wood, K.; Kline, A.; Furiga, A.; Rausch, M.; Jan, Y.
The satellite switched frequency division multiple access system provided a detailed system architecture that supports a point to point communication system for long haul voice, video and data traffic between small Earth terminals at Ka band frequencies at 30/20 GHz. A detailed system design is presented for the space segment, small terminal/trunking segment at network control segment for domestic traffic model A or B, each totaling 3.8 Gb/s of small terminal traffic and 6.2 Gb/s trunk traffic. The small terminal traffic (3.8 Gb/s) is emphasized, for the satellite router portion of the system design, which is a composite of thousands of Earth stations with digital traffic ranging from a single 32 Kb/s CVSD voice channel to thousands of channels containing voice, video and data with a data rate as high as 33 Mb/s. The system design concept presented, effectively optimizes a unique frequency and channelization plan for both traffic models A and B with minimum reorganization of the satellite payload transponder subsystem hardware design. The unique zoning concept allows multiple beam antennas while maximizing multiple carrier frequency reuse. Detailed hardware design estimates for an FDMA router (part of the satellite transponder subsystem) indicate a weight and dc power budget of 353 lbs, 195 watts for traffic model A and 498 lbs, 244 watts for traffic model B.
Sheikh, N. M.
It was great to be associated with Prof. Dr. Karl Rawer. He devoted his life to make use of the wonderful laboratory of Nature, the Ionosphere. Through acquisition of the experimental data from AEROS satellites and embedding it with data from ground stations, it was possible to achieve a better empirical model, the International Reference Ionosphere. Prof. Dr. Karl Rawer has been as dynamic as the Ionosphere. His vision about the ionospheric data is exceptional and has helped the scientific and engineering community to make use of his vision in advancing the dimensions of empirical modelling. As a human being, Prof. Dr. Karl Rawer has all the traits of an angel from Heaven. In short he developed a large team of researchers forming a blooming tree from the parent node. Ionosphere still plays an important role in over the horizon HF Radar and GPs satellite data reduction.
Hurley, M.; Duffey, T.; Huffine, Christopher; Weldy, Ken; Clevland, Jeff; Hauser, Joe
The Secretary of Defense's Office of Force Transformation (OFT) is currently undertaking an initiative to develop a low-cost, responsive, operationally relevant space capability using small satellites. The Naval Research Laboratory (NRL) is tasked to be program manger for this initiative, which seeks to make space assets and capabilities available to operational users. TacSat-1 is the first in a series of small satellites that will result in rapid, tailored, and operationally relevant experimental space capabilities for tactical forces. Components of the resulting tactical architecture include a highly automated small satellite bus, modular payloads, common launch and payload interfaces, tasking and data dissemination using the SIPRNET (Secret Internet Protocol Routing Network), and low cost, rapid response launches. The overall goal of TacSat-1 is to demonstrate the utility of a broader complementary business model and provide a catalyst for energizing DoD and industry in the operational space area. This paper first provides a brief overview of the TacSat- 1 experiment and then discusses the engineering designs and practices used to achieve the aggressive cost and schedule goals. Non-standard approaches and engineering philosophies that allowed the TacSat-1 spacecraft to be finished in twelve months are detailed and compared with "normal" satellite programs where applicable. Specific subsystem design, integration and test techniques, which contributed to the successful completion of the TacSat-1 spacecraft, are reviewed. Finally, lessons learned are discussed.
M. J. Behrenfeld
Full Text Available Phytoplankton photosynthesis links global ocean biology and climate-driven fluctuations in the physical environment. These interactions are largely expressed through changes in phytoplankton physiology, but physiological status has proven extremely challenging to characterize globally. Phytoplankton fluorescence does provide a rich source of physiological information long exploited in laboratory and field studies, and is now observed from space. Here we evaluate the physiological underpinnings of global variations in satellite-based phytoplankton chlorophyll fluorescence. The three dominant factors influencing fluorescence distributions are chlorophyll concentration, pigment packaging effects on light absorption, and light-dependent energy-quenching processes. After accounting for these three factors, resultant global distributions of quenching-corrected fluorescence quantum yields reveal a striking consistency with anticipated patterns of iron availability. High fluorescence quantum yields are typically found in low iron waters, while low quantum yields dominate regions where other environmental factors are most limiting to phytoplankton growth. Specific properties of photosynthetic membranes are discussed that provide a mechanistic view linking iron stress to satellite-detected fluorescence. Our results present satellite-based fluorescence as a valuable tool for evaluating nutrient stress predictions in ocean ecosystem models and give the first synoptic observational evidence that iron plays an important role in seasonal phytoplankton dynamics of the Indian Ocean. Satellite fluorescence may also provide a path for monitoring climate-phytoplankton physiology interactions and improving descriptions of phytoplankton light use efficiencies in ocean productivity models.
A novel strategy for automatic satellite constellation design with satellite diversity is proposed. The automatic satellite constellation design means some parameters of satellite constellation design can be determined simultaneously. The total number of satellites, the altitude of satellite, the angle between planes, the angle shift between satellites and the inclination angle are considered for automatic satellite constellation design. Satellite constellation design is modelled using a mult...
Burton, J. C.; MacAyeal, D. R.; Nakamura, N.
Lab-scale models of geophysical phenomena have a long history in research and education. For example, at the University of Chicago, Dave Fultz developed laboratory-scale models of atmospheric flows. The results from his laboratory were so stimulating that similar laboratories were subsequently established at a number of other institutions. Today, the Dave Fultz Memorial Laboratory for Hydrodynamics (http://geosci.uchicago.edu/~nnn/LAB/) teaches general circulation of the atmosphere and oceans to hundreds of students each year. Following this tradition, we have constructed a lab model of iceberg-capsize dynamics for use in the Fultz Laboratory, which focuses on the interface between glaciology and physical oceanography. The experiment consists of a 2.5 meter long wave tank containing water and plastic "icebergs". The motion of the icebergs is tracked using digital video. Movies can be found at: http://geosci.uchicago.edu/research/glaciology_files/tsunamigenesis_research.shtml. We have had 3 successful undergraduate interns with backgrounds in mathematics, engineering, and geosciences perform experiments, analyze data, and interpret results. In addition to iceberg dynamics, the wave-tank has served as a teaching tool in undergraduate classes studying dam-breaking and tsunami run-up. Motivated by the relatively inexpensive cost of our apparatus (~1K-2K dollars) and positive experiences of undergraduate students, we hope to serve as a model for undergraduate research and education that other universities may follow.
Craighead, J. J.; Craighead, F. C., Jr.; Varney, J. R.; Cote, C. E.
Description of a feasibility experiment recently performed to test the use of a satellite system for telemetering environmental and physiological data from the winter den of a 'hibernating' black bear, Ursus americanus. The instrumentation procedure and evaluations of the equipment performance and sensory data obtained are discussed in detail.
Shmirko, Konstantin; Bobrikov, Alexey; Pavlov, Andrey
Atmosphere responses for more than 90% of all radiation measured by satellite. Due to this, atmospheric correction plays an important role in separating water leaving radiance from the signal, evaluating concentration of various water pigments (chlorophyll-A, DOM, CDOM, etc). The elimination of atmospheric intrinsic radiance from remote sensing signal referred to as atmospheric correction.
Kirkegaard, Jonas Rasmussen; Breinbjerg, M.; Højlund, M. K.
around or displaced arbitrarily in a given landscape. In the web browser, the different sound streams from the individual satellites can be mixed together to form a cooperative soundscape. The project thus allows people to tune into and explore the overheard soundscape of everyday life in a collaborative...
Vovchyk, Yeva; Blagodyr, Yaroslav; Kraynyuk, Gennadiy; Bilinsky, Andriy; Lohvynenko, Alexander; Klym, Bogdan; Pochapsky, Yevhen
Problems associated with polarimetric observations of low Earth orbit artificial satellites as important solar system objects are discussed. The instrumentation (the optical and mechanical parts, the control and drive electronics, and the application software) for performing such observations is also described
Mobile satellite (MSAT) technology is the basis for a new component of the telecommunications industry capable of providing services to small inexpensive subscriber terminals located almost any place in the world. The market for MSAT space segment capacity (bandwidth and power) is a natural monopoly that can be logically and technically…
long run, this is not bad since it generates self-confidence and self-reliance - which in the final analysis are .... hopes to find some new X-ray sources. The second ... from the state of health of the satellite can be judged. A tracking network gives ...
Fitzpatrick, Austin J.; Leon, Nancy J.; Novati, Alexander; Lincoln, Laura K.; Fisher, Diane K.
GOES-R: Satellite Insight seeks to bring awareness of the GOES-R (Geostationary Operational Environmental Satellite -- R Series) satellite currently in development to an audience of all ages on the emerging medium of mobile games. The iPhone app (Satellite Insight) was created for the GOES-R Program. The app describes in simple terms the types of data products that can be produced from GOES-R measurements. The game is easy to learn, yet challenging for all audiences. It includes educational content and a path to further information about GOESR, its technology, and the benefits of the data it collects. The game features action-puzzle game play in which the player must prevent an overflow of data by matching falling blocks that represent different types of GOES-R data. The game adds more different types of data blocks over time, as long as the player can prevent a data overflow condition. Points are awarded for matches, and players can compete with themselves to beat their highest score.
Fraser, Doug; Stott, Ken
Among the 60 or so university satellite campuses in Australia are many that are probably failing to meet the high expectations of their universities and the communities they were designed to serve. While in some cases this may be due to the demand driven system, it may also be attributable in part to the ways in which they are managed. The…
Journal of Chemical Education, 2004
The availability of abundant water resources in the Upper Midwest of the United States is nullified by their contamination through heavy commercial and industrial activities. Scientists have taken the responsibility of detecting the water quality of these resources through remote-sensing satellites to develop a wide-ranging water purification plan…
Munchak, S. J.; Huffman, G. J.
Of the possible sources of precipitation data, those based on satellites provide the greatest spatial coverage. There is a wide selection of datasets, algorithms, and versions from which to choose, which can be confusing to non-specialists wishing to use the data. The International Precipitation Working Group (IPWG) maintains tables of the major publicly available, long-term, quasi-global precipitation data sets (http://www.isac.cnr.it/ ipwg/data/datasets.html), and this talk briefly reviews the various categories. As examples, NASA provides two sets of quasi-global precipitation data sets: the older Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) and current Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (GPM) mission (IMERG). Both provide near-real-time and post-real-time products that are uniformly gridded in space and time. The TMPA products are 3-hourly 0.25°x0.25° on the latitude band 50°N-S for about 16 years, while the IMERG products are half-hourly 0.1°x0.1° on 60°N-S for over 3 years (with plans to go to 16+ years in Spring 2018). In addition to the precipitation estimates, each data set provides fields of other variables, such as the satellite sensor providing estimates and estimated random error. The discussion concludes with advice about determining suitability for use, the necessity of being clear about product names and versions, and the need for continued support for satellite- and surface-based observation.
S. H. Hwang
Full Text Available The magnetometer is one of the most important payloads of scientific satellites to monitor the near-earth space environment. The electromagnetic variations of the space environment can be observed with the electric and magnetic field measurements. In practice, it is well known that the measurement of magnetic fields needs less technical complexities than that of electric fields in space. Therefore the magnetometer has long been recognized as one of the basic payloads for the scientific satellites. In this paper, we discuss the scientific fluxgate magnetometer which will be on board the KITSAT-3. The main circuit design of the present magnetometer is based on that of KISAT-1 and -2 but its facilities have been re-designed to improve the resolution to about 5nT for scientific purpose. The calibration and noise level test of this circuit have been performed at the laboratory of the Tierra Tecnica company in Japan.
A Generic Mission Operations System using Expert System technology to demonstrate the potential of Artificial Intelligence (AI) automated monitor and control functions in a Mission Operations and Satellite Test environment will be developed at the National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory (JPL). Expert system techniques in a real time operation environment are being studied and applied to science and engineering data processing. Advanced decommutation schemes and intelligent display technology will be examined to develop imaginative improvements in rapid interpretation and distribution of information. The Generic Payload Operations Control Center (GPOCC) will demonstrate improved data handling accuracy, flexibility, and responsiveness in a complex mission environment. The ultimate goal is to automate repetitious mission operations, instrument, and satellite test functions by the applications of expert system technology and artificial intelligence resources and to enhance the level of man-machine sophistication.
National Oceanic and Atmospheric Administration, Department of Commerce — Satellite tagging was implemented in 2013. Satellite tagging is conducted using a Dan Inject air rifle and deployment arrows designed by Wildlife Computers. Two...
The likely performance envelope and architecture for satellite cinema systems are derived from simple practical assumptions. A case is made for possible transatlantic cooperation towards establishing a satellite cinema standard.
Keeney, James T
.... Space offers a near-perfect vacuum to operate a passive or active sensor. Volume, mass and power on satellites is limited and risk management approaches tended to remove such sensors from satellite systems...
Keeney, James T
.... Space offers a near-perfect vacuum to operate a passive or active sensor. Volume, mass and power on satellites is limited and risk management approaches tended to remove such sensors from satellite systems...
Including an introduction and historical overview of the field, this comprehensive synthesis of the major biophysical applications of satellite remote sensing includes in-depth discussion of satellite-sourced biophysical metrics such as leaf area index.
National Aeronautics and Space Administration — The Core Flight System Satellite Starter Kit (cFS Kit) will allow a small satellite or CubeSat developer to rapidly develop, deploy, test, and operate flight... | <urn:uuid:177ec636-058a-4580-a2a1-e50af4d586ec> | 2.546875 | 83,348 | Content Listing | Science & Tech. | 23.598028 | 95,593,218 |
EDH Proteins Reshape Cell Membranes
News Feb 27, 2017 | Original Story from the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC)
Small “bubbles” frequently form on membranes of cells and are taken up into their interior. The process involves EHD proteins, a focus of research by Prof. Oliver Daumke of the MDC. He and his team have now shed light on how these proteins assemble on the surface of a cell and reshape its membrane.
Fairground entertainers can transform simple balloons into elaborate figures with just a few twists. They do this by “pinching off” sections of the balloon’s surface – a method similar to that used by cells to create small bubbles known as vesicles for the transport of molecules. Vesicles are used to take up nutrients and play an important role in the transmission of neural signals.
Molecular machines reshape the membrane
EHD proteins are one type of molecular machine responsible for the creation of vesicles. These proteins bind themselves to the inside of a cell membrane, where they form long chains and ring-like structures. The rings then invaginate the membrane, contract like a drawstring, and, finally, detach the vesicle from the surface of the cell.
Oliver Daumke of the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) is investigating the function and spatial structure of these EHD proteins. In an earlier study, he and his team analyzed the three-dimensional structure of EHDs in an inactive form – i.e. not bound to the membrane. Until now, scientists did not know how EHD proteins become activated, attach to the membrane and shape it into tubular structures.
The protein flips open to reveal specialized regions
Together with international colleagues, Daumke and his PhD student Arthur Alves de Melo have now published an article in the current issue of the scientific journal PNAS that describes the active form of this molecular EHD machine – that which occurs when it comes into contact with the membrane. Comparing the active and inactive protein structures, they discovered that EHD molecules flip open when they bind to the membrane, exposing specialized regions. One of these regions allows them to organize in extended chains and ring-like structures. Another region reorients toward the membrane and anchors the molecular machines on the cell surface.
With this work, Daumke’s team has now described two steps in the operation of EHDs. “To understand the complete operating cycle and thus the full function of these molecular EHD machines, we must now analyze various other states,” he says. “That is a task for the coming years.”
Melo, A. A., Hegde, B. G., Shah, C., Larsson, E., Isas, J. M., Kunz, S., … Daumke, O. (2017). Structural insights into the activation mechanism of dynamin-like EHD ATPases. Proceedings of the National Academy of Sciences. doi:10.1073/pnas.1614075114
This article has been republished from materials provided by the Max Delbrück Center for Molecular Medicine. Note: material may have been edited for length and content. For further information, please contact the cited source.
‘Good Cholesterol’ May Not Always be Good for Postmenopausal WomenNews
Postmenopausal factors may have an impact on the heart-protective qualities of high-density lipoproteins (HDL) – also known as ‘good cholesterol’ – according to a study led by researchers in the University of Pittsburgh Graduate School of Public Health.READ MORE
What Makes Good Brain Proteins Turn Bad?News
The protein FUS is implicated in two neurodegenerative diseases: amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Using a newly developed fruit fly model, researchers have zoomed in on the protein structure of FUS to gain more insight into how it causes neuronal toxicity and disease. | <urn:uuid:14f9c0e1-0848-48e1-858a-e674fd7a8183> | 3.21875 | 866 | News Article | Science & Tech. | 43.919653 | 95,593,222 |
Welcome to the Northern Ireland Branch of Butterfly Conservation, which was first formed in 1988 and currently has more than 300 members.
If you live in the region and are a member of Butterfly Conservation you automatically become a member of the Northern Ireland branch.
Northern Ireland is home to around 1000 species of moth and 25 species of butterfly, with almost half of these being priority species.
One of these, the Cryptic Wood White (thought to be Real's Wood White until recent research proved it to be a new species entirely) is only found in Northern Ireland. Craigavon Lakes Local Nature Reserve in County Armagh is the very best place to visit to see this butterfly on the wing during May and June.
Species to look out for
Find out more
Spotted a butterfly in Northern Ireland and want to tell us? You can view or add your own butterfly and moth sightings here.
You can also contact our recorders directly:
We work with the Centre for Environmental Data and Recording to collate all of our online records.
If you want to ID a moth you've seen or to find out more about the moths you can find all over Ireland, please visit the Moths of Ireland website.
In the UK, since 1976, the habitat specialists butterflies index has fallen by 77%, whilst wider countryside abundance is down by 46%.
An increasing number of new moth species are arriving and settling in the UK as a result of the global reach of the horticultural trade and the changing climate, moth experts today revealed.
The Chequered Skipper has been returned to England after 40 year absence
Alan Titchmarsh is calling on gardeners to make a metre for wildlife this summer by providing a refuge for struggling butterflies, moths and other pollinators.
Saturday 21st July 2018: 1pm
Washing Bay/Peatlands Park
Northern Ireland Branch Big Butterfly Count walk to see Purple Hairstreak at Washing Bay and Peatlands Park. Lead by Ian Rippy.
Saturday 15th September 2018, 9.45am-3.00pm
Lough Neagh Discovery Centre, Oxford Island, Craigavon
Our third annual ‘Thank You’ to volunteers and recorders who support the UK Butterfly Monitoring Scheme through walking transects and undertaking surveys, although anyone with an interest in butterflies is welcome!
Saturday 29th September 2018, 10.30am-3.30pm
Lagan Valley Regional Park Visitor Centre, Belfast
Join us for an introduction to leaf miners for beginners
Ways to Get Involved!
Butterflies and moths can bring the whole family together, especially during the school holidays. Check out our family-friendly resources:
Get involved in the Ireland Butterfly Atlas project!
Make your own Moth Trap
Butterfly & Moth Life Cycle Chart For Children
Children's ID Guide For Moths And Their Caterpillars
Create A Butterfly Fuel Station In Your Garden
Create A Munch Box For Caterpillars In Your Garden
Make Your Own Plant Labels | <urn:uuid:6a174df5-f979-42c8-9a51-8a391959df99> | 2.890625 | 627 | About (Org.) | Science & Tech. | 48.386621 | 95,593,268 |
Normally, no environment variables need to be set. Most of the environment variables used by Mesa/Gallium are for debugging purposes, but they can sometimes be useful for debugging end-user issues.
LibGL environment variables
- LIBGL_DEBUG - If defined debug information will be printed to stderr. If set to 'verbose' additional information will be printed.
- LIBGL_DRIVERS_PATH - colon-separated list of paths to search for DRI drivers
- LIBGL_ALWAYS_INDIRECT - if set to `true`, forces an indirect rendering context/connection.
- LIBGL_ALWAYS_SOFTWARE - if set to `true`, always use software rendering
- LIBGL_NO_DRAWARRAYS - if set to `true`, do not use DrawArrays GLX protocol (for debugging)
- LIBGL_SHOW_FPS - print framerate to stdout based on the number of glXSwapBuffers calls per second.
- LIBGL_DRI3_DISABLE - disable DRI3 if set to `true`.
Core Mesa environment variables
- MESA_NO_ASM - if set, disables all assembly language optimizations
- MESA_NO_MMX - if set, disables Intel MMX optimizations
- MESA_NO_3DNOW - if set, disables AMD 3DNow! optimizations
- MESA_NO_SSE - if set, disables Intel SSE optimizations
- MESA_NO_ERROR - if set to 1, error checking is disabled as per KHR_no_error. This will result in undefined behaviour for invalid use of the api, but can reduce CPU use for apps that are known to be error free.
- MESA_DEBUG - if set, error messages are printed to stderr. For example,
if the application generates a GL_INVALID_ENUM error, a corresponding error
message indicating where the error occurred, and possibly why, will be
printed to stderr.
For release builds, MESA_DEBUG defaults to off (no debug output). MESA_DEBUG accepts the following comma-separated list of named flags, which adds extra behaviour to just set MESA_DEBUG=1:
- silent - turn off debug messages. Only useful for debug builds.
- flush - flush after each drawing command
- incomplete_tex - extra debug messages when a texture is incomplete
- incomplete_fbo - extra debug messages when a fbo is incomplete
- context - create a debug context (see GLX_CONTEXT_DEBUG_BIT_ARB) and print error and performance messages to stderr (or MESA_LOG_FILE).
- MESA_LOG_FILE - specifies a file name for logging all errors, warnings, etc., rather than stderr
- MESA_TEX_PROG - if set, implement conventional texture env modes with fragment programs (intended for developers only)
- MESA_TNL_PROG - if set, implement conventional vertex transformation operations with vertex programs (intended for developers only). Setting this variable automatically sets the MESA_TEX_PROG variable as well.
- MESA_EXTENSION_OVERRIDE - can be used to enable/disable extensions. A value such as "GL_EXT_foo -GL_EXT_bar" will enable the GL_EXT_foo extension and disable the GL_EXT_bar extension.
- MESA_EXTENSION_MAX_YEAR - The GL_EXTENSIONS string returned by Mesa is sorted by extension year. If this variable is set to year X, only extensions defined on or before year X will be reported. This is to work-around a bug in some games where the extension string is copied into a fixed-size buffer without truncating. If the extension string is too long, the buffer overrun can cause the game to crash. This is a work-around for that.
- MESA_GL_VERSION_OVERRIDE - changes the value returned by
glGetString(GL_VERSION) and possibly the GL API type.
- The format should be MAJOR.MINOR[FC|COMPAT]
- FC is an optional suffix that indicates a forward compatible context. This is only valid for versions >= 3.0.
- COMPAT is an optional suffix that indicates a compatibility context or GL_ARB_compatibility support. This is only valid for versions >= 3.1.
- GL versions <= 3.0 are set to a compatibility (non-Core) profile
- GL versions = 3.1, depending on the driver, it may or may not have the ARB_compatibility extension enabled.
- GL versions >= 3.2 are set to a Core profile
- Examples: 2.1, 3.0, 3.0FC, 3.1, 3.1FC, 3.1COMPAT, X.Y, X.YFC,
- 2.1 - select a compatibility (non-Core) profile with GL version 2.1.
- 3.0 - select a compatibility (non-Core) profile with GL version 3.0.
- 3.0FC - select a Core+Forward Compatible profile with GL version 3.0.
- 3.1 - select GL version 3.1 with GL_ARB_compatibility enabled per the driver default.
- 3.1FC - select GL version 3.1 with forward compatibility and GL_ARB_compatibility disabled.
- 3.1COMPAT - select GL version 3.1 with GL_ARB_compatibility enabled.
- X.Y - override GL version to X.Y without changing the profile.
- X.YFC - select a Core+Forward Compatible profile with GL version X.Y.
- X.YCOMPAT - select a Compatibility profile with GL version X.Y.
- Mesa may not really implement all the features of the given version. (for developers only)
- MESA_GLES_VERSION_OVERRIDE - changes the value returned by
glGetString(GL_VERSION) for OpenGL ES.
- The format should be MAJOR.MINOR
- Examples: 2.0, 3.0, 3.1
- Mesa may not really implement all the features of the given version. (for developers only)
- MESA_GLSL_VERSION_OVERRIDE - changes the value returned by glGetString(GL_SHADING_LANGUAGE_VERSION). Valid values are integers, such as "130". Mesa will not really implement all the features of the given language version if it's higher than what's normally reported. (for developers only)
- MESA_GLSL_CACHE_DISABLE - if set to `true`, disables the GLSL shader cache
- MESA_GLSL_CACHE_MAX_SIZE - if set, determines the maximum size of the on-disk cache of compiled GLSL programs. Should be set to a number optionally followed by 'K', 'M', or 'G' to specify a size in kilobytes, megabytes, or gigabytes. By default, gigabytes will be assumed. And if unset, a maximum size of 1GB will be used. Note: A separate cache might be created for each architecture that Mesa is installed for on your system. For example under the default settings you may end up with a 1GB cache for x86_64 and another 1GB cache for i386.
- MESA_GLSL_CACHE_DIR - if set, determines the directory to be used for the on-disk cache of compiled GLSL programs. If this variable is not set, then the cache will be stored in $XDG_CACHE_HOME/mesa (if that variable is set), or else within .cache/mesa within the user's home directory.
- MESA_GLSL - shading language compiler options
- MESA_NO_MINMAX_CACHE - when set, the minmax index cache is globally disabled.
- MESA_SHADER_CAPTURE_PATH - see Capturing Shaders
- MESA_SHADER_DUMP_PATH and MESA_SHADER_READ_PATH - see Experimenting with Shader Replacements
- MESA_VK_VERSION_OVERRIDE - changes the Vulkan physical device version
as returned in VkPhysicalDeviceProperties::apiVersion.
- The format should be MAJOR.MINOR[.PATCH]
- This will not let you force a version higher than the driver's instance versionas advertised by vkEnumerateInstanceVersion
- This can be very useful for debugging but some features may not be implemented correctly. (For developers only)
Mesa Xlib driver environment variables
The following are only applicable to the Mesa Xlib software driver. See the Xlib software driver page for details.
- MESA_RGB_VISUAL - specifies the X visual and depth for RGB mode
- MESA_CI_VISUAL - specifies the X visual and depth for CI mode
- MESA_BACK_BUFFER - specifies how to implement the back color buffer, either "pixmap" or "ximage"
- MESA_GAMMA - gamma correction coefficients for red, green, blue channels
- MESA_XSYNC - enable synchronous X behavior (for debugging only)
- MESA_GLX_FORCE_CI - if set, force GLX to treat 8bpp visuals as CI visuals
- MESA_GLX_FORCE_ALPHA - if set, forces RGB windows to have an alpha channel.
- MESA_GLX_DEPTH_BITS - specifies default number of bits for depth buffer.
- MESA_GLX_ALPHA_BITS - specifies default number of bits for alpha channel.
i945/i965 driver environment variables (non-Gallium)
- INTEL_NO_HW - if set to 1, prevents batches from being submitted to the hardware. This is useful for debugging hangs, etc.
- INTEL_DEBUG - a comma-separated list of named flags, which do various things:
- ann - annotate IR in assembly dumps
- aub - dump batches into an AUB trace for use with simulation tools
- bat - emit batch information
- blit - emit messages about blit operations
- blorp - emit messages about the blorp operations (blits & clears)
- buf - emit messages about buffer objects
- clip - emit messages about the clip unit (for old gens, includes the CLIP program)
- color - use color in output
- cs - dump shader assembly for compute shaders
- do32 - generate compute shader SIMD32 programs even if workgroup size doesn't exceed the SIMD16 limit
- dri - emit messages about the DRI interface
- fbo - emit messages about framebuffers
- fs - dump shader assembly for fragment shaders
- gs - dump shader assembly for geometry shaders
- hex - print instruction hex dump with the disassembly
- l3 - emit messages about the new L3 state during transitions
- miptree - emit messages about miptrees
- no8 - don't generate SIMD8 fragment shader
- no16 - suppress generation of 16-wide fragment shaders. useful for debugging broken shaders
- nocompact - disable instruction compaction
- nodualobj - suppress generation of dual-object geometry shader code
- norbc - disable single sampled render buffer compression
- optimizer - dump shader assembly to files at each optimization pass and iteration that make progress
- perf - emit messages about performance issues
- perfmon - emit messages about AMD_performance_monitor
- pix - emit messages about pixel operations
- prim - emit messages about drawing primitives
- reemit - mark all state dirty on each draw call
- sf - emit messages about the strips & fans unit (for old gens, includes the SF program)
- shader_time - record how much GPU time is spent in each shader
- spill_fs - force spilling of all registers in the scalar backend (useful to debug spilling code)
- spill_vec4 - force spilling of all registers in the vec4 backend (useful to debug spilling code)
- state - emit messages about state flag tracking
- submit - emit batchbuffer usage statistics
- sync - after sending each batch, emit a message and wait for that batch to finish rendering
- tcs - dump shader assembly for tessellation control shaders
- tes - dump shader assembly for tessellation evaluation shaders
- tex - emit messages about textures.
- urb - emit messages about URB setup
- vert - emit messages about vertex assembly
- vs - dump shader assembly for vertex shaders
- INTEL_SCALAR_VS (or TCS, TES, GS) - force scalar/vec4 mode for a shader stage (Gen8-9 only)
- INTEL_PRECISE_TRIG - if set to 1, true or yes, then the driver prefers accuracy over performance in trig functions.
Radeon driver environment variables (radeon, r200, and r300g)
- RADEON_NO_TCL - if set, disable hardware-accelerated Transform/Clip/Lighting.
EGL environment variables
Mesa EGL supports different sets of environment variables. See the Mesa EGL page for the details.
Gallium environment variables
- GALLIUM_HUD - draws various information on the screen, like framerate, cpu load, driver statistics, performance counters, etc. Set GALLIUM_HUD=help and run e.g. glxgears for more info.
- GALLIUM_HUD_PERIOD - sets the hud update rate in seconds (float). Use zero to update every frame. The default period is 1/2 second.
- GALLIUM_HUD_VISIBLE - control default visibility, defaults to true.
- GALLIUM_HUD_TOGGLE_SIGNAL - toggle visibility via user specified signal. Especially useful to toggle hud at specific points of application and disable for unencumbered viewing the rest of the time. For example, set GALLIUM_HUD_VISIBLE to false and GALLIUM_HUD_TOGGLE_SIGNAL to 10 (SIGUSR1). Use kill -10 <pid> to toggle the hud as desired.
- GALLIUM_HUD_DUMP_DIR - specifies a directory for writing the displayed hud values into files.
- GALLIUM_DRIVER - useful in combination with LIBGL_ALWAYS_SOFTWARE=true for choosing one of the software renderers "softpipe", "llvmpipe" or "swr".
- GALLIUM_LOG_FILE - specifies a file for logging all errors, warnings, etc. rather than stderr.
- GALLIUM_PRINT_OPTIONS - if non-zero, print all the Gallium environment variables which are used, and their current values.
- GALLIUM_DUMP_CPU - if non-zero, print information about the CPU on start-up
- TGSI_PRINT_SANITY - if set, do extra sanity checking on TGSI shaders and print any errors to stderr.
- DRAW_FSE - ???
- DRAW_NO_FSE - ???
- DRAW_USE_LLVM - if set to zero, the draw module will not use LLVM to execute shaders, vertex fetch, etc.
- ST_DEBUG - controls debug output from the Mesa/Gallium state tracker. Setting to "tgsi", for example, will print all the TGSI shaders. See src/mesa/state_tracker/st_debug.c for other options.
Clover state tracker environment variables
- CLOVER_EXTRA_BUILD_OPTIONS - allows specifying additional compiler and linker options. Specified options are appended after the options set by the OpenCL program in clBuildProgram.
- CLOVER_EXTRA_COMPILE_OPTIONS - allows specifying additional compiler options. Specified options are appended after the options set by the OpenCL program in clCompileProgram.
- CLOVER_EXTRA_LINK_OPTIONS - allows specifying additional linker options. Specified options are appended after the options set by the OpenCL program in clLinkProgram.
Softpipe driver environment variables
- SOFTPIPE_DUMP_FS - if set, the softpipe driver will print fragment shaders to stderr
- SOFTPIPE_DUMP_GS - if set, the softpipe driver will print geometry shaders to stderr
- SOFTPIPE_NO_RAST - if set, rasterization is no-op'd. For profiling purposes.
- SOFTPIPE_USE_LLVM - if set, the softpipe driver will try to use LLVM JIT for vertex shading processing.
LLVMpipe driver environment variables
- LP_NO_RAST - if set LLVMpipe will no-op rasterization
- LP_DEBUG - a comma-separated list of debug options is accepted. See the source code for details.
- LP_PERF - a comma-separated list of options to selectively no-op various parts of the driver. See the source code for details.
- LP_NUM_THREADS - an integer indicating how many threads to use for rendering. Zero turns off threading completely. The default value is the number of CPU cores present.
VMware SVGA driver environment variables
- SVGA_FORCE_SWTNL - force use of software vertex transformation
- SVGA_NO_SWTNL - don't allow software vertex transformation fallbacks (will often result in incorrect rendering).
- SVGA_DEBUG - for dumping shaders, constant buffers, etc. See the code for details.
- SVGA_EXTRA_LOGGING - if set, enables extra logging to the vmware.log file, such as the OpenGL program's name and command line arguments.
- See the driver code for other, lesser-used variables.
WGL environment variables
- WGL_SWAP_INTERVAL - to set a swap interval, equivalent to calling wglSwapIntervalEXT() in an application. If this environment variable is set, application calls to wglSwapIntervalEXT() will have no effect.
VA-API state tracker environment variables
- VAAPI_MPEG4_ENABLED - enable MPEG4 for VA-API, disabled by default.
VC4 driver environment variables
- VC4_DEBUG - a comma-separated list of named flags, which do various things:
- cl - dump command list during creation
- qpu - dump generated QPU instructions
- qir - dump QPU IR during program compile
- nir - dump NIR during program compile
- tgsi - dump TGSI during program compile
- shaderdb - dump program compile information for shader-db analysis
- perf - print during performance-related events
- norast - skip actual hardware execution of commands
- always_flush - flush after each draw call
- always_sync - wait for finish after each flush
- dump - write a GPU command stream trace file (VC4 simulator only)
Other Gallium drivers have their own environment variables. These may change frequently so the source code should be consulted for details. | <urn:uuid:5f62c026-0086-41bb-b68d-f954e050da25> | 2.6875 | 4,211 | Documentation | Software Dev. | 35.682785 | 95,593,286 |
Physical chemistry is an application of chemistry and physics. On the other hand, Physics has been defined as the application characteristics of matter that are mutual for all substances. Although, chemistry includes the study of the characteristics of specific materials. It includes the study that involves techniques, measurements and theories associated with physics.
Physical chemistry involves the analysis of physical properties based on the various scales that possess distinct types of substances. The study of different scales of a chemical property of material is stated below:
Macroscopic: It is a property of a material that describes the proximity of a substance that behaves as a group.
Microscopic: These properties are mainly concerned with in-depth details of physical properties of material, that would be detectable only under a microscope.
Atomic: This property is primarily concerned with elements.
Subatomic: It involves theories and subatomic structures that forms a vital part of nuclear chemistry.
Physical Chemistry Examples
Below are some of the simple examples wherein the techniques and theories are used to describe physical chemistry that you have come across school syllabus.
- Theory of Radioactivity
- Analysis of Solutions and Solubility
- Gas Laws and associated theories
- Static Electricity
- X-Ray Diffraction
Physical Chemistry Equations
Physical chemistry is a quantitative technology wherein equations will frequently be given. It could be beneficial to a factor out that equations may be of diverse types, a few equations outline belonging like “strain equals pressure over the place”.
It gives quantitative members of the family for a great wide variety of phenomena encountered in chemistry, primarily based on well defined and measurable residences.
Best Books For Physical Chemistry
If someone needs an “all-in-one” undergraduate level copy, Levine Physical Chemistry is good. Atkin’s Physical Chemistry is one more “all-in-one” text. Pradeep’s Chemistry is helpful. One can make use of O.P. Tandon as a good reference too.
- CBSE Chapter-wise Questions-Answers: Chemistry Previous Year’ Questions by Sharma P
- A Collection of Fully Solved Questions asked from 2014 – 2008 Exam by Purnima Sharma (CBSE Chapterwise Solutions)
- Chemistry (Class – XII) by NCERT
- Concise Inorganic Chemistry 5th Edition (Paperback) by J. D. Lee
- Modern’s ABC of Chemistry Class – 12 (Part 1 & 2) (With CD) by S. P. Jauhar
- Pradeep’s New Course Chemistry Class-XII (Set Of 2 Volumes) by Pradeep Publications.
Related Articles On Physical Chemistry
Practise This Question | <urn:uuid:f7aca17c-fc13-443b-ac36-911c9a71b12d> | 3.78125 | 555 | Knowledge Article | Science & Tech. | 27.510227 | 95,593,305 |
|Debugging with GDB|
This chapter documents gdb's just-in-time (JIT) compilation interface. A JIT compiler is a program or library that generates native executable code at runtime and executes it, usually in order to achieve good performance while maintaining platform independence.
Programs that use JIT compilation are normally difficult to debug because portions of their code are generated at runtime, instead of being loaded from object files, which is where gdb normally finds the program's symbols and debug information. In order to debug programs that use JIT compilation, gdb has an interface that allows the program to register in-memory symbol files with gdb at runtime.
If you are using gdb to debug a program that uses this interface, then it should work transparently so long as you have not stripped the binary. If you are developing a JIT compiler, then the interface is documented in the rest of this chapter. At this time, the only known client of this interface is the LLVM JIT.
Broadly speaking, the JIT interface mirrors the dynamic loader interface. The JIT compiler communicates with gdb by writing data into a global variable and calling a fuction at a well-known symbol. When gdb attaches, it reads a linked list of symbol files from the global variable to find existing code, and puts a breakpoint in the function so that it can find out about additional code. | <urn:uuid:0f858680-c8dd-4598-bc1b-730d20ab7bd4> | 3.203125 | 290 | Documentation | Software Dev. | 37.5425 | 95,593,318 |
A group of researchers led by Melina Bersten of Kavli IPMU recently presented a model that provides the first characterization of the progenitor for a hydrogen-deficient supernova.
Their model predicts that a bright hot star, which is the binary companion to an exploding object, remains after the explosion. To verify their theory, the group secured observation time with the Hubble Space Telescope (HST) to search for such a remaining star. Their findings, which are reported in the October 2014 issue of The Astronomical Journal, have important implications for the evolution of massive stars.
For years astronomers have searched for the elusive progenitors of hydrogen-deficient stellar explosions without success. However, this changed in June 2013 with the appearance of supernova iPTF13bvn and the subsequent detection of an object at the same location in archival images obtained before the explosion using the HST.
The interpretation of the observed object is controversial. The team led by Bersten presented a self-consistent picture using models of supernova brightness and progenitor evolution. In their picture, the more massive star in a binary system explodes after transferring mass to its companion.
One of the challenges in astrophysics is identifying which star produces which supernova. This is particularly problematic for supernovae without hydrogen, which are called Types Ib or Ic, because the progenitors have yet to be detected directly.
However, the ultimate question is: “How do progenitor stars remove their hydrogen-rich envelopes during their evolution?” Two competing mechanisms have been proposed. One hypothesizes that a strong wind produced by a very massive star blows the outer hydrogen layers, while the other suggests that a gravitationally bound binary companion star removes the outer layers.
The latter case does not require a very massive star. Because these two scenarios predict vastly different progenitor stars, direct detection of the progenitor for this type of supernova can provide definitive clues about the preferred evolutionary path.
When young Type Ib supernova iPTF13bvn was discovered in nearby spiral galaxy NGC 5806, astronomers hoped to find its progenitor. Inspecting the available HST images did indeed reveal an object, providing optimism that the first hydrogen-free supernova progenitor would at last be identified. Due to the object’s blue hue, it was initially suggested that the object was a very hot, very massive, evolved star with a compact structure, called a “Wolf-Rayet” star. (Using models of such stars, a group based in Geneva was able to reproduce the brightness and color of the pre-explosion object with a Wolf-Rayet star that was born with over 30 times the mass of the Sun and died with 11 times the solar mass.)
"Based on such suggestions, we decided to check if such a massive star is consistent with the supernova brightness evolution," says Melina Bersten. However, the results are inconsistent with a Wolf-Rayet star; the exploding star must have been merely four times the mass of the Sun, which is much smaller than a Wolf-Rayet star. “If the mass was this low and the supernova lacked hydrogen, our immediate conclusion is that the progenitor was part of a binary system,” adds Bersten.
Because the problem requires a more elaborate solution, the team set out to simulate the evolution of a binary system with mass transfer in order to determine a configuration that can explain all the observational evidence (a blue pre-explosion object with a relatively low mass devoid of hydrogen). “We tested several configurations and came up with a family of possible solutions,” explains Omar Benvenuto of IALP, Argentina.
“Interestingly, the mass transfer process dictates the observational properties of the exploding star, so it allows suitable solutions to be derived even if the mass of the stars is varied,” adds Benvenuto. The team chose the case where two stars are born with 20 and 19 times the mass of the Sun. The mass transfer process causes the larger star to retain only four times the solar mass before exploding. Most importantly, the smaller star may trap part of the transferred mass, becoming a very bright and hot star.
The existence of a hot star would provide strong evidence for the binary model presented by Bersten and collaborators. Fortunately, such a prediction can be directly tested once the supernova fades because the hot companion should become evident. “We have requested and obtained observation time with the HST to search for the companion star in 2015,” comments Gaston Folatelli of Kavli IPMU. “Until then, we must wait patiently to see if we can identify the progenitor of a hydrogen-free supernova for the first time,” Bersten adds.
(Originally published by the University of Tokyo)
James Cohen | Eurek Alert!
Computer model predicts how fracturing metallic glass releases energy at the atomic level
20.07.2018 | American Institute of Physics
What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
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20.07.2018 | Materials Sciences | <urn:uuid:b5ab17f1-1d2b-46f3-b935-2f329bed4cb1> | 3.390625 | 1,580 | Content Listing | Science & Tech. | 35.054526 | 95,593,321 |
Sea ice around Antarctica shrank in a warm period more than 100,000 years ago, an indication that man-made climate change could also trigger an abrupt retreat, a scientific report said Tuesday.
A thaw would reverse a paradoxical expansion of the extent of floating ice on the ocean around the frozen continent in recent decades, apparently defying the trend of global warming blamed on greenhouse gases.
Winter sea ice around Antarctica shrank 65 percent in a natural warm period between Ice Ages about 128,000 years ago, when temperatures were slightly warmer than now, according to the report in the journal Nature Communications.
The conclusions were based on ancient ice cores drilled from deep in the Antarctic ice sheet. The chemistry of snow indicates how far it blew from the ocean before it landed and got compressed into ice.
The ancient shrinking of the ice helps underpin forecasts by a panel of UN climate experts that global warming will mean a 58 percent retreat in Antarctica’s sea ice by around the year 2200, the British scientific team that wrote the report concluded.
“A major reduction at 128,000 years ago could indicate a tipping point in the sea ice system,” they wrote.
Lead author Max Holloway of the British Antarctic Survey (BAS) told Reuters that the ancient shrinking of sea ice may have preceded a collapse of an ice sheet in West Antarctica that spilled into the sea and pushed up sea levels.
“With a major reduction in sea ice, you’d expect the ice sheets to be more sensitive,” he said. Separately, in 2014 another study suggested that some glaciers in West Antarctica have already begun an irreversible thaw.
Sceptics who reject mainstream scientific findings about global warming often point to the expansion of sea ice around Antarctica as evidence. Sea ice in the Arctic at the other end of the planet has been shrinking in recent decades.
Scientists say the contradictory trends may partly be because Antarctica is a continent surrounded by an open ocean, while the Arctic is an ocean surrounded by land – mainly Russia, Canada, Greenland and Alaska.
“By uncovering, for the first time, a huge retreat around Antarctica, we have established that sea ice in the Southern Hemisphere is also susceptible to major climate changes,” co-author Louise Sime of BAS said in a statement. | <urn:uuid:248a715c-2b4c-4d59-afec-1ec63ce1c029> | 3.8125 | 472 | News Article | Science & Tech. | 33.602245 | 95,593,335 |
H R, H P and CV are all related to the standard temperature of 25°C. The enthalpy of the entering air is considered to be sensible heat only (i.e. the fuel/air is considered to be a dry mixture).
The enthalpy of the flue gas must be consistent with the calorific value of the fuel which is used in the balance. If the gross calorific value is used, then H R should contain a latent heat term equal to the mass of water produced per kilogram of fuel multiplied by the latent heat of evaporation of water at 25°C (h fg). If the net calorific value is used, then the flue gas enthalpy will consist of sensible heat terms only. In this chapter we are concerned with predicting the temperature reached within the flame, hence the net calorific value/sensible heat terms system is the more appropriate.
KeywordsCombustion Product Flame Temperature Bituminous Coal Gross Calorific Value Heat Term
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Researchers at Duke University in North Carolina (US) have created a new technique to make hybrid thin-film materials. The study could provide an avenue to scale-up hybrid perovskite thin-film deposition for solar cells and also pave the way to new light-emitting diodes and photodetectors.
Methylammonium lead iodide (MAPbI3) is the perovskite most commonly used in solar technologies and one of the few perovskites that can be fabricated with standard production techniques. And yet, the solar industry needs innovative production techniques to overcome the significant challenges that still remain in making these organic-inorganic thin-film materials. The delicate organic elements are critical to the hybrid material´s ability to absorb and emit light effectively. MAPbI3 at least has a very simple organic component " but is an excellent light absorber. The goal is to build more complex molecular combinations to enable better materials. Duke´s new approach to making hybrid perovskites could be a huge leap in that direction.
Matrix-assisted pulsed laser evaporation
The new technique, called resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE for short) was developed over the past decade by Adrienne Stiff-Roberts, associate professor in the Department of Electrical and Computer Engineering at Duke. “Matrix-assisted pulsed laser evaporation is a gentle technique for the thin-film deposition of organic and hybrid materials,” she says. “By using a low-energy, infrared laser to evaporate a solvent matrix containing the desired target materials, complex organic and hybrid materials and device structures are enabled that otherwise could not be easily achieved in solution-based deposition.”
The new technique could be a game-changer for perovskites. “RIR-MAPLE will help hybrid perovskites mature into a general class of crystalline organic-inorganic semiconductors by providing thin-film synthesis of perovskite heterostructures, regardless of solubility,” says Stiff-Roberts.
What is more, RIR-MAPLE offers major advantages, compared with previous techniques. “Contrary to other approaches for physical vapor deposition of hybrid perovskites, RIR-MAPLE can deposit stoichiometric films without an excess of the organic component in the target,” notes the professor. “This control over the organic molecule deposition rate enables the compositional control required for gradient or layered structures.” Thus, the study could have notable impact on the design of the next generation of solar cells. “By demonstrating that RIR-MAPLE is capable of producing hybrid perovskite solar cells with material quality and device performance comparable to other deposition techniques, our study provides an avenue to scale-up hybrid perovskite thin-film deposition for solar cells,” the expert confirms.
Enabling light-based technologies beyond solar
Besides a new generation of solar cells, these new hybrid organic-inorganic crystals could enable other advanced light-based technologies. “As a new potential semiconductor technology, hybrid perovskites could be useful for a number of optoelectronic devices, including light-emitting diodes, photodetectors and optical modulators,” says Stiff-Roberts. She goes on to discuss an unexpected aspect of the research. “The most surprising outcome of this study was the smaller grain sizes observed in RIR-MAPLE-deposited films, despite strong similarities in other material properties,” she reveals. “While the reason for the smaller grains is not currently known, such morphology could actually be useful for enhancing radiative recombination in light-emitting diodes.”
The professor says her next steps in this research are to better understand the formation of hybrid perovskite crystals during RIR-MAPLE deposition and to characterize material properties of hybrid perovskites comprising more complex organic molecules.
The research is published in the journal ACS Energy Letters, under the title “MAPbI3 Solar Cells with Absorber Deposited by Resonant Infrared Matrix-Assisted Pulsed Laser Evaporation.”
Written by Sandra Henderson, Research Editor, Novus Light Technologies Today | <urn:uuid:4b259c91-d2b1-47c2-bd22-eb1ddb3e589d> | 3.109375 | 896 | News (Org.) | Science & Tech. | 8.468897 | 95,593,347 |
Power is the rate at which energy is transferred, used or transformed. The unit of power is a joule per second (J/s), which is also known as a watt. The more wattage the more power or electrical energy is used per unit time. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts.
The transfer of energy can be used to do work. Therefore, the power is the rate at which this work is performed. The same amount of work is done when carrying a load up a hill whether the person walks or runs. However, more power is expended during the running because the work is done in a shorter amount of time.
Power can be calculated using different variables in the equations below:
Mechanical power is the combination of forces and movement. Power is the product of a force on an object and the object’s velocity. Mechanical power also describes the time derivative of work. If a mechanical system has no losses than the input power must equal the output power.© BrainMass Inc. brainmass.com July 22, 2018, 10:11 pm ad1c9bdddf | <urn:uuid:e38eb866-4364-4cdd-b364-671c550c76e5> | 3.9375 | 239 | Knowledge Article | Science & Tech. | 57.52398 | 95,593,349 |
is the displacement of solids (soil
and other particles) by the agents of wind, water or ice, by downward or down-slope movement in response to gravity
or by living organisms (in the case of bioerosion
). Erosion is distinguished from weathering
, which is the breaking down of rock and particles through processes where no movement is involved, although the two processes may be concurrent.
Erosion is a natural process, but in many places it is increased by human land use. Poor land use practices include deforestation, overgrazing, unmanaged construction activity and road or trail building. However, improved land use practices can limit erosion, using techniques like terrace-building and tree planting.
A certain amount of erosion is natural and, in fact, healthy for the ecosystem. For example, gravels continually move downstream in watercourses. Excessive erosion, however, can cause problems, such as receiving water sedimentation, ecosystem damage (including fish kills) and outright loss of soil. | <urn:uuid:a8fc07f4-0181-44f1-81ca-30ab4abce47f> | 4.15625 | 211 | Knowledge Article | Science & Tech. | 25.237808 | 95,593,391 |
As the Earth warms and glaciers all over the world begin to melt, researchers and public policy experts have focused largely on how all of that extra water will contribute to sea level rise But another impact lurking in that inevitable scenario is carbon.
More specifically, what happens to all of the organic carbon found in those glaciers when they melt?
That's the focus of a new paper by a research team that includes Florida State University assistant professor Robert Spencer. The study, published in Nature Geoscience, is the first global estimate by scientists at what happens when major ice sheets break down.
"This is the first attempt to figure out how much organic carbon is in glaciers and how much will be released when they melt," Spencer said. "It could change the whole food web. We do not know how different ecological systems will react to a new influx of carbon."
Glaciers and ice sheets contain about 70 percent of the Earth's freshwater and ongoing melting is a major contributor to sea level rise. But, glaciers also store organic carbon derived from both primary production on the glaciers and deposition of materials such as soot or other fossil fuel combustion byproducts.
Spencer, along with colleagues from Alaska and Switzerland, studied measurements from ice sheets in mountain glaciers globally, the Greenland ice sheet and the Antarctic ice sheet to measure the total amount of organic carbon stored in the global ice reservoir.
It's a lot.
Specifically, as glaciers melt, the amount of organic carbon exported in glacier outflow will increase 50 percent over the next 35 years. To put that in context, that's about the amount of organic carbon in half of the Mississippi River being added each year to the ocean from melting glaciers.
"This research makes it clear that glaciers represent a substantial reservoir of organic carbon," said Eran Hood, the lead author on the paper and a scientist with the University of Alaska Southeast. "As a result, the loss of glacier mass worldwide, along with the corresponding release of carbon, will affect high-latitude marine ecosystems, particularly those surrounding the major ice sheets that now receive fairly limited land-to-ocean fluxes of organic carbon."
Spencer said he and his colleagues are continuing on this line of research and will do additional studies to try to determine exactly what the impact will be when that carbon is released into existing bodies of water.
"The thing people have to think about is what this means for the Earth," Spencer said. "We know we're losing glaciers, but what does that mean for marine life, fisheries, things downstream that we care about? There's a whole host of issues besides the water issue."
Other institutions collaborating on the paper are University of Alaska Southeast, Ecole Polytechnique Fédérale de Lausanne and the Alaska Science Center.
Kathleen Haughney | EurekAlert!
Further reports about: > Antarctic ice > Antarctic ice sheet > GLACIERS > Greenland ice > Greenland ice sheet > Melting glaciers > Nature Geoscience > ecological systems > fossil fuel combustion > ice sheet > ice sheets > marine ecosystems > marine life > mountain glaciers > sea level > sea level rise
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
17.07.2018 | Information Technology
17.07.2018 | Materials Sciences
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No stars in the clouds
Search for missing galaxies in high-speed galactic gas clouds comes up empty, Pitt researcher finds
A team of astronomers from the University of Pittsburgh and the Universitäts-Sternwarte München in Munich, Germany, announced today in a paper presented at the meeting of the American Astronomical Society in Washington, D.C., that their search for dwarf galaxies in fast-moving clouds of gas has yielded no results, leading them to suggest alternative avenues of research to find the supposedly "missing" galaxies.
The team, which includes Regina Schulte-Ladbeck, associate dean for undergraduate studies and professor of physics and astronomy in Pitts School of Arts and Sciences, and Ulrich Hopp of the Universitäts-Sternwarte München, has been searching for stars in high-velocity clouds. However, said Schulte-Ladbeck, "Our searches have come up empty."
The mathematical simulations that astronomers use to establish how galaxies were formed predict that every giant galaxy should have a few hundred "dwarf" galaxy companions. But in our own neighborhood, the Milky Way Galaxy, there are only 50 or so such dwarves.
One simple way to explain the difference would be if the missing dwarf galaxies were located in high-velocity clouds, astronomer Leo Blitz of the University of California, Berkeley, and his colleagues had suggested. Schulte-Ladbeck and Hopp hoped to measure the distances between the clouds and the Milky Way to obtain proof that the clouds indeed held additional satellite galaxies of our Milky Way.
To search for stars in the clouds, the researchers took a two-pronged approach. First, they used the Two Micron All Sky Survey, a survey conducted by the University of Massachusetts and funded primarily by NASA and the National Science Foundation, to look for bright stars in circular patches of sky two degrees across, the area typically covered by the gas clouds that make the most promising dwarf galaxy candidates.
Second, using accurate positions of where most of the hydrogen gas in several clouds is located--supplied to them by radio astronomer Jürgen Kerp of the University of Bonn--the researchers also trained one of the 8-meter (315-inch) telescopes of the European Southern Observatorys Very Large Telescope, located in northern Chiles Atacama Desert, on small regions within the clouds to search if any faint stars had formed there. However, neither of these methods turned up any stars.
In their paper, Schulte-Ladbeck and Hopp conclude that it is unlikely that hundreds of additional dwarf satellites of the Milky Way have been somehow "hiding" from observers, and they encourage astronomers to pursue other solutions to the discrepancy.
Karen Hoffmann | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the... | <urn:uuid:85e46dc6-cbc1-4de9-97f3-8f9f06474e59> | 2.921875 | 1,122 | Content Listing | Science & Tech. | 31.575138 | 95,593,413 |
Publications and more
Learn more about space weather and Met Office space weather operations by reading our publications and presentations, and watching a selection of videos and animations.
Brochures and datasheets
Learn more about space weather, its impacts on Earth and how these impacts are monitored.
View our recent presentation about verification of space weather forecasts.
View our recent presentation about the importance of heliospheric observations and measurements for space weather forecasting.
Videos and animations
Animation showing how what happens on the Sun affects us on Earth.
Alex Deakin explains how and why the Northern Lights occur.
Space weather describes events in space that can impact our lives here on Earth. | <urn:uuid:8f318302-f3b1-4078-87d2-d3438e94c3db> | 2.53125 | 139 | Content Listing | Science & Tech. | 27.637297 | 95,593,414 |
Photosynthetic algae have been refining their technique for capturing light for millions of years. As a result, these algae boast powerful light-harvesting systems -- proteins that absorb light to be turned into energy -- that scientists have long aspired to understand and mimic for renewable energy applications.
Now, researchers at Princeton University have revealed a mechanism that enhances the light harvesting rates of the cryptophyte algae Chroomonas mesostigmatica. Published in the journal Chem on December 8, these findings provide valuable insights for the design of artificial light-harvesting systems such as molecular sensors and solar energy collectors.
Cryptophyte algae often live below other organisms that absorb most of the sun's rays. In response, the algae have evolved to thrive on wavelengths of light that aren't captured by their neighbors above, mainly the yellow-green colors. The algae collects this yellow-green light energy and passes it through a network of molecules that converts it into red light, which chlorophyll molecules need to perform important photosynthetic chemistry.
The speed of the energy transfer through the system has both impressed and perplexed the scientists that study them. The Scholes lab's predictions were always about three times slower than the observed rates. "The timescales that the energy is moved through the protein -- we could never understand why the process so fast," said corresponding author Gregory Scholes, the William S. Tod Professor of Chemistry at Princeton University.
In 2010, Scholes' team found evidence that the culprit behind these fast rates was a strange phenomenon called quantum coherence, in which molecules could share electronic excitation and transfer energy according to quantum mechanical probability laws instead of classical physics. But the research team couldn't explain exactly how coherence worked to speed up the rates until now.
Using a sophisticated method enabled by ultrafast lasers, the researchers were able to measure the molecules' light absorption and essentially track the energy flow through the system. Normally the absorption signals would overlap, making them impossible to assign to specific molecules within the protein complex, but the team was able to sharpen the signals by cooling the proteins down to very low temperatures, said Jacob Dean, lead author and postdoctoral researcher in the Scholes lab.
The researchers observed the system as energy was transferred from molecule to molecule, from high-energy green light to lower energy red light, with excess energy lost as vibrational energy. These experiments revealed a particular spectral pattern that was a 'smoking gun' for vibrational resonance, or vibrational matching, between the donor and acceptor molecules, Dean said.
This vibrational matching allowed energy to be transferred much faster than it otherwise would be by distributing the excitation between molecules. This effect provided a mechanism for the previously reported quantum coherence. Taking this redistribution into account, the researchers recalculated their prediction and landed on a rate that was about three times faster.
"Finally the prediction is in the right ballpark," Scholes said. "Turns out that it required this quite different, surprising mechanism."
The Scholes lab plans to study related proteins to investigate if this mechanism is operative in other photosynthetic organisms. Ultimately, scientists hope to create light-harvesting systems with perfect energy transfer by taking inspiration and design principles from these finely tuned yet extremely robust light-harvesting proteins. "This mechanism is one more powerful statement of the optimality of these proteins," Scholes said.
Read the full article here:
Dean, J. C.; Mirkovic, T.; Toa, Z. S. D.; Oblinsky, D. G.; Scholes, G. D. "Vibronic Enhancement of Algae Light Harvesting." Chem 2016, 1, 858.
This work was supported as part of the Photosynthetic Antenna Research Center, an Energy Frontier Research Center funded by the Basic Energy Sciences program of the US Department of Energy Office of Science under award DE-SC0001035.
Tien Nguyen | EurekAlert!
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
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Authors: Claude Michael Cassano
Based on my 1984 linearization of the Klein-Gordon equations, potential functions generalizations of the electric and magnetic field strengths form a basis from which a compound model simply constructs the leptons; the simple differences between the quarks and leptons; how the quarks arose from the leptons; why there are these two types of fermions; and why there are precisely three generations for each of these types. The most elementary particle interactions classify the interactions between strong and weak, and further still between the W and Z type of weak interactions. Two simple conservation requirements give rise to all the fundamental particle interactions, and describe the structure of the weak intermediate envelopes. Further, a simple charge function determines the charge of every object. Further still, the only free assignable parameters for the entire model are four mass constants for each fermion generation. This is essentially a summary of my book: "A Mathematical Preon Foundation for the Standard Model"; but starting from the different standpoint of my Helmholtzian operator matrix product, rather than my constructive algebras (developed primarily in "Reality is a Mathematical Model" and "The Weighted Matrix Product").
Comments: 6 Pages.
[v1] 2018-06-21 06:09:24
Unique-IP document downloads: 19 times
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Add your own feedback and questions here:
You are equally welcome to be positive or negative about any paper but please be polite. If you are being critical you must mention at least one specific error, otherwise your comment will be deleted as unhelpful. | <urn:uuid:d9507cbb-706f-4382-a63f-f6cf00e41e06> | 2.625 | 416 | Academic Writing | Science & Tech. | 31.001487 | 95,593,508 |
LLVM compiler infrastructure
LLVM is a compiler infrastructure designed for compile-time, link-time, runtime, and idle-time optimization of programs from arbitrary programming languages. The compiler infrastructure includes mirror sets of programming tools as well as libraries with equivalent functionality.
Source Files (show merged sources derived from linked package)
|README.packaging||00000076057.43 KB||1527683130about 2 months ago|
|_link||0000000128128 Bytes||1529163377about 1 month ago|
|baselibs.conf||000000005959 Bytes||1473443314almost 2 years ago|
|llvm.changes||000004618145.1 KB||1527683130about 2 months ago|
|llvm.spec||00000089628.75 KB||1527683130about 2 months ago| | <urn:uuid:6353f8d6-59e3-417c-a9f4-850a64c5ecde> | 2.609375 | 185 | Content Listing | Software Dev. | 55.765966 | 95,593,533 |
Date of publication: 2017-08-22 12:50
Geothermal or ground-source air conditioning and heat pump systems use long U-shaped tubes in deep wells or an array of horizontal tubes buried in a large area through which the working fluid is circulated, and heat is transferred to or from the earth. Other systems use rivers or ocean water to heat or cool the working fluid.
The power of moving water is obvious to anyone who has stood amidst breaking waves or struggled to swim against a river’s current. New technologies enable us to harness the might of rivers, tides, and waves for electricity.
Power = Current x Voltage (P = I V)
6 Watt is the power from a current of 6 Ampere flowing through 6 Volt.
6 kilowatt is a thousand Watts.
6 kilowatt-hour is the energy of one kilowatt power flowing for one hour. (E = P t).
6 kilowatt-hour (kWh) = x 65 6 J = million Joules
In Warren&rsquo s long poem, The Ballad of Billie Potts , the maple tree comparison is followed by another simile: &ldquo And full of tricks as a lop-eared pup.&rdquo
It’s illegal to go dancing in Fargo with a hat on. It is even illegal to wear a hat at a party where other people are dancing. It is also illegal in North Dakota to take a nap with your shoes on. After 66 pm, it is illegal to set off fireworks at Devil’s Lake in North Dakota.
When gas is heated, it expands however, when that gas is confined, it increases in pressure. If the bottom wall of the confinement chamber is the top of a movable piston, this pressure exerts a force on the surface of the piston causing it to move downward. This movement can then be harnessed to do work equal to the total force applied to the top of the piston times the distance that the piston moves.
Only 65% of energy in a light bulb is used to create light. Ninety percent of a light bulb’s energy creates heat. Compact fluorescent light bulbs (CFLs), on the other hand, use about 85% less electricity than conventional bulbs and last up to 67 times as long. | <urn:uuid:ab2139ea-1a57-48ba-b85d-3d4f8acdc3ce> | 3.171875 | 481 | Knowledge Article | Science & Tech. | 65.203705 | 95,593,540 |
[Tutor] Curious newbie
Mon, 22 Jul 2002 12:27:26 -0500
Python is an interpreted language, which means that one must have a Python
interpreter installed in order to run Python programs. There are certain
special things you can do, such as bundle up a Python interpreter with your
program for distribution, so there are different ways of looking at it.
> -----Original Message-----
> From: firstname.lastname@example.org [mailto:email@example.com]On Behalf Of
> shey crompton
> Sent: Monday, July 22, 2002 12:16 PM
> To: 'firstname.lastname@example.org'
> Subject: [Tutor] Curious newbie
> Hi all,
> If I create a program like a small text based guessing game using Python,
> and I want to send it to mates to try out, do they have to have python
> installed to be able to play the game? If my mates don't have to have IDLE
> installed, how would they (in windows) run the game?
> Tutor maillist - Tutor@python.org | <urn:uuid:be82febf-c1e5-4b7f-8c36-0c390d1950d8> | 3.03125 | 252 | Comment Section | Software Dev. | 61.756228 | 95,593,547 |
Graphite oxide is one of the main precursors of graphene-based materials, which are highly promising for various technological applications because of their unusual electronic properties. Although epoxy and hydroxyl groups are widely accepted as its main functionalities, the complete structure of graphite oxide has remained elusive. By interpreting spectroscopic data in the context of the major functional groups believed to be present in graphite oxide, we now show evidence for the presence of five- and six-membered-ring lactols. On the basis of this chemical composition, we devised a complete reduction process through chemical conversion by sodium borohydride and sulfuric acid treatment, followed by thermal annealing. Only small amounts of impurities are present in the final product (less than 0.5 wt% of sulfur and nitrogen, compared with about 3 wt% with other chemical reductions). This method is particularly effective in the restoration of the pi-conjugated structure, and leads to highly soluble and conductive graphene materials.
Mendeley saves you time finding and organizing research
Choose a citation style from the tabs below | <urn:uuid:fdbed9ce-d2bb-4686-9b8d-629d01370939> | 2.78125 | 225 | Academic Writing | Science & Tech. | 12.891207 | 95,593,580 |
Forage fish declining, jellyfish booming in most densely developed parts of Puget Sound
The most populated areas of Puget Sound have experienced striking shifts in marine species, with declines in herring and smelt that have long provided food for other marine life and big increases in the catch of jellyfish, which contribute far less to the food chain, according to new research that tracks species over the last 40 years.
The parallel trends of rising human population and declining forage fish such as herring and smelt indicate that human influences such as pollution and development may be eroding species that long dominated Puget Sound. In particular, the rise of jellyfish blooms may divert energy away from highly-productive forage species that provide food for larger fish and predators such as salmon, seabirds and marine mammals.
The research by scientists from NOAA Fisheries' Northwest Fisheries Science Center, the University of Washington and the Washington Department of Fish and Wildlife was published in April in Marine Ecology Progress Series.
"On land people see the changes that come with human population increases, but underwater the changes are much harder to discern," said Correigh Greene, a research fisheries biologist at NWFSC and lead author of the new research. "What this tells us is that when you look over time, you can see that the underwater landscape of Puget Sound is changing too."
The scientists mined data from trawl surveys of fish species in Puget Sound in the 1970s and 80s, in some cases salvaging records destined for the recycling bin and converting handwritten data to electronic format. Then they compared those early results to similar results from their own surveys in 2003 and 2011 to detect changes in the abundance and distribution of forage fish species and jellyfish.
They also looked for connections between the changes in species and outside influences such as human population growth, commercial fishing and shifts in climate.
What they found was declines in some species and increases in others. Pacific herring and surf smelt, historically the two most abundant forage fish, declined by as much as two orders of magnitude in the most heavily populated areas of Puget Sound. Sand lance and three-spine stickleback increased across all four Puget Sound sub-basins examined, but these smaller fish species translate into less prey overall for larger fish, birds and marine mammals.
The Puget Sound Partnership cites Pacific herring as an indicator of ecosystem health in Puget Sound.
Jellyfish blooms also rose alongside human population across Puget Sound, with jellyfish-dominated catches jumping three to nine-fold in the same sub-basins where herring and smelt declined. In some cases more than nine of every 10 tows of trawl survey nets in recent years brought in catches dominated by jellyfish.
The shifts suggest that the same disturbed conditions linked to declines in herring and smelt may benefit more opportunistic jellyfish, which then further pressure forage fish by competing with them for food or even consuming their eggs and larvae. But jellyfish offer far less nutrition than the declining forage fish, reducing the food and energy available to species higher on the food chain.
Harvest of forage fish may open new opportunities for jellyfish by reducing competition from other species and human-driven changes in habitat may reduce the productivity of forage fish, scientists suggest. Polluted runoff may also shift prey towards types that jellyfish favor.
The research may also help resolve the mystery of why juvenile salmon survival has declined sharply in Puget Sound. While forage fish may compete with salmon in some circumstances, they also serve as prey for salmon and can help absorb some pressure from predators such as seals that might otherwise consume young salmon. The parallel declines of forage fish and juvenile salmon survival suggests the loss of forage fish may also affect salmon.
"We still have to pin down mechanisms and causes, but there is clearly a compelling pattern of change in Puget Sound food webs that may be linked to human influence," said Casey Rice, a research fish biologist at the NWFSC and co-author of the new paper. "These results are a potent reminder of just how important such field studies are in detecting, diagnosing and managing impacts on natural resources."
Declines in forage fish were most closely related to human population density, while commercial fishing and climate were less important factors, the research found.
The results may help guide habitat protection and restoration by focusing it on less-disturbed parts of Puget Sound that remain important habitat for forage fish, the researchers concluded. The findings also suggest that efforts to rebuild forage fish populations should take into account human pressures that may be driving unrecognized changes in marine ecosystems.
"We were fortunate to find the long-term data that allowed us to detect these changes in Puget Sound," said Lauren Kuehne, a research scientist at the University of Washington and co-author of the research. "This really demonstrates the value of data that may have been collected many years ago for different reasons but helps us see the changes that are affecting ecosystems today."
Michael Milstein | EurekAlert!
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
17.07.2018 | Life Sciences
17.07.2018 | Information Technology
17.07.2018 | Power and Electrical Engineering | <urn:uuid:0e037410-e28d-40d1-853f-a990abb37d56> | 3.09375 | 1,698 | Content Listing | Science & Tech. | 37.436558 | 95,593,592 |
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Dr. Miriam Douglass
Dr. Martin McClinton
In this interactive object, learners calculate formula and molecular weights by working through five examples and two problems.
Solubility of Ionic Compounds in Water
By Dr. Miriam Douglass, Dr. Martin McClinton
Learners view movie clips to determine the solubility of two ionic compounds. They also examine a solubility chart and predict the solubility of compounds.
Boiling Point of a Liquid
By Debbie McClinton, Dr. Miriam Douglass, Dr. Martin McClinton
Learners examine how the boiling point increases with increasing pressure. An example from industry is given.
By Terry Bartelt
Learners view an animated presentation showing how the pH level of a cleaning solution is controlled in a closed-loop system in a manufacturing setting. A quiz completes the activity.
Calculating Gas Density from Standard Molar Volume
By Dr. Miriam Douglass
Learners calculate gas density from the standard molar volume and observe how the density increases with the increasing molecular weight of the gas.
Hi im looking for some information regarding Nickel Aluiminium Bronze alloy. can you please give the
1. Chemical formula for the alloy NAB C95800
2. The formula weight
Creative Commons Attribution-NonCommercial 4.0 International License.
Learn more about the license » | <urn:uuid:c2e5a7b5-d7e8-48dd-bcd0-83a3d607e8fc> | 3.453125 | 339 | Truncated | Science & Tech. | 44.765532 | 95,593,594 |
A double pendulum consists of a pendulum of mass m2 hanging from a pendulum of mass m1. The motion of both parts of the double pendulum is constrained to the x-y plane. Both strings are "unstretchable" and having length I2 and I1, respectively.
a) How many degrees of freedom does this system have?
Using the variable theta1 and theta2 for the angles the strings make with the vertical, write expressions for
b) the kinetic energy
c) the potential energy
d) Write the equations of motion for the system in terms in theta1 and theta 2, and their time derivatives.© BrainMass Inc. brainmass.com July 18, 2018, 7:04 am ad1c9bdddf
The solution determines the kinetic and potential energy. | <urn:uuid:07da871f-b59e-42db-ac30-bb9742bdd0d7> | 3.296875 | 173 | Tutorial | Science & Tech. | 60.926791 | 95,593,601 |
A certain subset of readers will remember a time when common knowledge held that sitting too close to the TV put you in mortal peril. We were warned to stay at least six feet back to avoid the X-rays supposedly pouring forth from the screen. Nobody but our moms believed it, so there we sat, transfixed and mere inches from the Radiation King, working on our tans as we caught up on the latest cartoons. We all grew up mostly OK, so it must have been a hoax.
Or was it? It turns out that getting X-rays from vacuum tubes is possible, at least if this barbecue lighter turned X-ray machine is legit. [GH] built it after playing with some 6J1 rectifier tubes and a 20-kV power supply yanked from an old TV, specifically to generate X-rays. It turned out that applying current between the filament and the plate made a Geiger counter click, so to simplify the build, the big power supply was replaced with the piezoelectric guts from a lighter. That worked too, but not for long — the tube was acting as a capacitor, storing up charge each time the trigger on the lighter was pulled, eventually discharging through and destroying the crystal. A high-voltage diode from a microwave oven in series with the crystal as a snubber fixed the problem, and now X-rays are as easy as lighting a grill.
We have to say we’re a wee bit skeptical here, and would love to see a video of a test. But the principle is sound, and if it works it’d be a great way to test all those homebrew Geiger counters we’ve featured, like this tiny battery-powered one, or this one based on the venerable 555 timer chip.
More energy hits the earth in sunlight every day than humanity could use in about 16,000 years or so, but that hasn’t stopped us from trying to tap into other sources of energy too. One source that shows promise is geothermal, but these methods have been hindered by large startup costs and other engineering challenges. A new way to tap into this energy source has been found however, which relies on capturing the infrared radiation that the Earth continuously gives off rather than digging large holes and using heat exchangers.
This energy is the thermal radiation that virtually everything gives off in some form or another. The challenge in harvesting this energy is that since the energy is in the infrared range, exceptionally tiny antennas are needed which will resonate at that frequency. It isn’t just fancy antennas, either; a new type of diode had to be manufactured which uses quantum tunneling to convert the energy into DC electricity.
While the scientists involved in this new concept point out that this is just a prototype at this point, it shows promise and could be a game-changer since it would allow clean energy to be harvested whenever needed, and wouldn’t rely on the prevailing weather. While many clean-energy-promising projects often seem like pipe dreams, we can’t say it’s the most unlikely candidate for future widespread adoption we’ve ever seen.
Few days are worse than a day when you hear the words, “I’m sorry, you have cancer.” Fear of the unknown, fear of pain, and fear of death all attend the moment when you learn the news, and nothing can prepare you for the shock of learning that your body has betrayed you. It can be difficult to know there’s something growing inside you that shouldn’t be there, and the urge to get it out can be overwhelming.
Sometimes there are surgical options, other times not. But eradicating the tumor is not always the job of a surgeon. Up to 60% of cancer patients will be candidates for some sort of radiation therapy, often in concert with surgery and chemotherapy. Radiation therapy can be confusing to some people — after all, doesn’t radiation cause cancer? But modern radiation therapy is a remarkably precise process that can selectively kill tumor cells while leaving normal tissue unharmed, and the machines we’ve built to accomplish the job are fascinating tools that combine biology and engineering to help people deal with a dreaded diagnosis.
Continue reading “The Physics of Healing: Radiation Therapy”
For his Hackaday Prize entry, [Carlos] is pushing the boundaries of what can be built with PCBs. He’s designed a very low-cost radiation detector that leverages pick and place machines, off-the-shelf components, and very simple electronics. It’s a novel ion chamber design, and if you ever needed a low-cost, easily manufacturable radiation detector, this is the project you want.
Instead of a Geiger tube or a spark detectors, this radiation detector uses an ionization chamber to detect radiation. This project was inspired by the work of [Charles Wenzel] and [Alan Yates], and the implementation is actually pretty simple. A metal can — or some other type of enclosure — is electrified, and a single wire is stuck right into the middle of the can. When alpha and beta particles enter the can, air molecules are ionized, and attracted to either the can or the wire by a difference in voltage. A tiny bit of current flows between the can and the wire, which can be detected if you have a sufficiently sensitive circuit.
The basic idea is well-publicised and well-understood. What [Carlos] is doing with this project is making an ionization chamber easily manufacturable. He’s doing this entirely with standard PCBs and solder instead of paint cans, RF connectors, and deadbugged transistors of the earlier experiments. The resulting PCB actually looks like something that wasn’t put together in a garage (even though it probably was), and is an amazing entry for the Hackaday Prize.
[Andreas Spiess] did a video earlier this year about fallout shelters. So it makes sense now he’s interested in having a Geiger counter connected to the network. He married a prefabricated counter with an ESP32. If it were just that simple, it wouldn’t be very remarkable, but [Andreas] also reverse-engineered the schematic for the counter and discusses the theory of operation, too. You can see the full video, below.
We often think we don’t need a network-connected soldering iron or toaster. However, if you have a radiological event, getting a cell phone alert might actually be useful. Of course, if that event was the start of World War III, you probably aren’t going to get the warning, but a reactor gas release or something similar would probably make this worth the $50.
Continue reading “Global Thermonuclear War: Tweeted”
[Radu Motisan] Has entered a cool project into the Best Product portion of this year’s Hackaday Prize. It’s called an Open Source IoT Dosimeter. It has a Geiger tube for detecting radiation levels along with Internet connectivity and a host of other goodies.
Dubbed the KIT1, this IoT dosimeter can be used as a portable radiation detector with its Nokia 5110 LCD as an output or a monitoring station with Ethernet. With its inbuilt speaker, it alerts users to areas with excessive radiation. KIT1 is a fully functioning system with no need for a computer to get readouts, making it very handy and easy to use. It also has room for expansion for extra sensors allowing a fully customized system. The project includes all the Gerbers and a BOM so you can send it off to a PCB fab lab of your choice, solder on a few components, and have a fully functioning IoT Dosimeter. you don’t even need the LCD or the Ethernet; you can choose which output you prefer from the two and just use that allowing for some penny-pinching.
This is a great project and who doesn’t need an IOT Dosimeter these days?
More than one hundred years ago, Henri Becquerel discovered that uranium emitted penetrating rays similar to those used by Wilhelm Röntgen to take the first X-ray image (of his wife’s hand), starting a new era of far-reaching applications. There are of course many dangers that come with the use of radioactivity, but there are also many beneficial uses for our society.
Continue reading “A Brief History of Radioactivity” | <urn:uuid:7c220bbe-c699-46fb-b55b-6880f3817d7b> | 2.84375 | 1,758 | Content Listing | Science & Tech. | 47.308238 | 95,593,603 |
Physicists at HZDR discover optimum conditions for laser plasma acceleration
Conventional electron accelerators have become an indispensable tool in modern research. The extremely bright radiation generated by synchrotrons, or free electron lasers, provides us with unique insights into matter at the atomic level. But even the smallest versions of these super microscopes are the size of a soccer field.
Laser plasma acceleration could offer an alternative: with a much smaller footprint and much higher peak currents it could be the basis for the next generation of compact light sources. So far, the challenge with laser accelerators has been to create a reliable and stable electron beam, which is the prerequisite for possible applications. Physicists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) have now developed a method to increase both beam stability and quality.
The basic principle of laser acceleration seems quite simple: A bundled, ultra-strong laser beam hits a trace of gas, which instantly creates plasma - an ionized state of matter or, in other words, a whirling mix of charged particles. The power of the light pulse pushes electrons away from their parent ions, creating a sort of bubble-like structure with a strong electric field in the plasma.
This field, which the laser pulse drags behind itself like a stern wave, traps the electrons, accelerating them to nearly the speed of light. "These speedy particles allow us to generate x-rays," Dr. Arie Irman from the HZDR Institute of Radiation Physics explains the purpose of the procedure. "For instance, when we make these electron bundles collide with another laser beam, the impact generates bright, ultra-short x-ray flashes - an immensely valuable research tool for examining extreme states of matter."
Right Time + Right Place = Perfect Acceleration
The strength of the secondary radiation greatly depends on the particles' electrical current. The current, in turn, is mostly determined by the number of electrons fed into the process. Laser-powered acceleration therefore holds great potential, because it reaches significantly higher peak currents in comparison with the conventional method. However, as physicist Jurjen Pieter Couperus points out, the so-called beam loading effect kicks in:
"These higher currents create an electric self-field strong enough to superimpose and disturb the laser-driven wave, distorting thereby the beam. The bundle is stretched out and not accelerated properly. The electrons therefore have different energies and quality levels." But in order to use them as a tool for other experiments, each beam must have the same parameters. "The electrons have to be in the right place at the right time," summarizes Couperus, who is a Ph.D. candidate in Irman's team.
Together with other colleagues at the HZDR, the two researchers were the first to demonstrate how the beam loading effect can be exploited for improved beam quality. They add a bit of nitrogen to the helium at which the laser beam is usually directed.
"We can control the number of electrons we feed into the process by changing the concentration of the nitrogen," Irman explains. "In our experiments, we found out that conditions are ideal at a charge of about 300 picocoulomb. Any deviation from it - if we add more or fewer electrons to the wave - results in a broader spread of energy, which impairs beam quality."
As the physicists' calculations have shown, experiments under ideal conditions yield peak currents of about 50 kiloamperes. "To put this in context, only about 0.6 kiloamperes flow through the standard overhead line for a German high-speed train," Jurjen Pieter Couperus explains. He is confident that they can beat their own record: "Using our findings and a laser pulse in the petawatt range, which our high-intensity laser DRACO can achieve, we should be able to generate a high-quality electron beam with peak currents of 150 kiloamperes. That would exceed modern large-scale research accelerators by about two orders of magnitude." An achievement which the researchers from Dresden believe would pave the way for the next generation of compact radiation sources.
Publication: J. P. Couperus, R. Pausch, A. Köhler, O. Zarini, J. M. Krämer, M. Garten, A. Huebl, R. Gebhardt, U. Helbig, S. Bock, K. Zeil, A. Debus, M. Bussmann, U. Schramm, A. Irman: Demonstration of a beam loaded nanocoulomb-class laser wakefield accelerator, in Nature Communications, 2017 (DOI: 10.1038/s41467-017-00592-7)
Simon Schmitt | Science Editor
phone: +49 351 260-3400 | email: email@example.com
The Helmholtz-Zentrum Dresden-Rossendorf (HZDR) performs research in the fields of energy, health, and matter. We focus on answering the following questions:
To help answer these research questions, HZDR operates large-scale facilities, which are also used by visiting researchers: the Ion Beam Center, the High-Magnetic Field Laboratory Dresden, and the ELBE Center for High-Power Radiation Sources. HZDR is a member of the Helmholtz Association and has five sites in Dresden, Freiberg, Grenoble, Hamburg and Leipzig with approximately 1,100 members of staff, of whom about 500 are scientists, including 150 Ph.D. candidates.
Simon Schmitt | EurekAlert!
What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin
Subaru Telescope helps pinpoint origin of ultra-high energy neutrino
16.07.2018 | National Institutes of Natural Sciences
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Life Sciences
18.07.2018 | Life Sciences
18.07.2018 | Information Technology | <urn:uuid:89fdd864-ff9f-427b-a043-b62b9753b815> | 3.8125 | 1,803 | Content Listing | Science & Tech. | 44.298404 | 95,593,609 |
Polonium is a radioactive metallic element, discovered by M and Mme Curie in 1898. It is found in small quantities in uranium ores. The isotope polonium-210 is produced by bombarding bismuth with neutrons. It is used in the control of static electricity. Symbol Po; atomic weight 210; atomic number 84; valence 2, 4. | <urn:uuid:d6b91d4d-6578-4c9b-963f-a6803264202f> | 3.4375 | 78 | Knowledge Article | Science & Tech. | 53.306333 | 95,593,627 |
|Scientific Name:||Sturnella magna (Linnaeus, 1758)|
|Taxonomic Source(s):||SACC. 2005 and updates. A classification of the bird species of South America. Available at: #http://www.museum.lsu.edu/~Remsen/SACCBaseline.htm#.|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Reviewer(s):||Butchart, S. & Symes, A.|
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (extent of occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
|Previously published Red List assessments:|
Native:Belize; Brazil; Canada; Colombia; Costa Rica; Cuba; El Salvador; French Guiana; Guatemala; Guyana; Honduras; Mexico; Nicaragua; Panama; Suriname; United States
Vagrant:Saint Pierre and Miquelon; Venezuela, Bolivarian Republic of
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The global population size has not been quantified.|
Trend Justification: This species has undergone a large and statistically significant decrease over the last 40 years in North America (-71.5% decline over 40 years, equating to a -26.9% decline per decade; data from Breeding Bird Survey and/or Christmas Bird Count: Butcher and Niven (2007).
|Current Population Trend:||Increasing|
|Amended reason:||Map updated.|
|Citation:||BirdLife International. 2017. Sturnella magna (amended version of 2016 assessment). The IUCN Red List of Threatened Species 2017: e.T22735434A119485103.Downloaded on 21 July 2018.|
|Feedback:||If you see any errors or have any questions or suggestions on what is shown on this page, please provide us with feedback so that we can correct or extend the information provided| | <urn:uuid:40a970d0-0558-4ed6-b196-bad5be44b939> | 3.265625 | 573 | Knowledge Article | Science & Tech. | 38.515984 | 95,593,635 |
Elephants have provided further evidence of their intelligence and self-awareness in an experiment involving a stick tied to a mat.
Researchers required Asian elephants to walk on to a mat, pick up a stick and pass it to an experimenter in exchange for a food reward.Survivor who lost family when tourist boat sank was told 'not to put on life jacket'
In control conditions the sticks were loose, but for the experiment the sticks were tied to the mat – meaning the elephant’s body weight prevented them passing the stick to the researcher unless they walked off the mat.
The University of Cambridge study found that elephants stepped off the mat on average 42 out of 48 times during the experiment, compared with three out of 48 during the control.
Researchers said this shows elephants are able to recognise their bodies as obstacles to success in problem-solving.
The sample size was 12 elephants at the Golden Triangle Asian Elephant Foundation in Thailand, and sets of 10 trials were run until the elephants passed the stick to the experimenter in five consecutive trials.
The test was devised by Dr Josh Plotnik, a visiting researcher at the University of Cambridge and founder of conservation charity Think Elephants International, and his colleague Rachel Dale.
‘Elephants are well regarded as one of the most intelligent animals on the planet, but we still need more empirical, scientific evidence to support this belief,’ said Ms Dale. ‘We know, for example, that they are capable of thoughtful co-operation and empathy, and are able to recognise themselves in a mirror.
‘These abilities are highly unusual in animals and very rare indeed in non-primates.
‘We wanted to see if they also show “body-awareness”.’
Self-awareness in animals and young children is usually tested using the mirror self-recognition test to see if they understand that the reflection is their own.
Only a few species other than humans have shown they can do this – great apes, dolphins, magpies and elephants.
Critics have argued that the mirror test is limited in its ability to demonstrate complex thoughts and understanding, and that it may be less useful in testing animals that rely less on vision than other species.
The stick and mat test was adapted from one in which children were asked to push a shopping trolley attached to a mat on which they were standing.
‘This is a deceptively simple test, but its implications are quite profound,’ said Dr Plotnik. ‘The elephants understood that their bodies were getting in the way, so they stepped aside to enable themselves to complete the task.
‘In a similar test, this is something that young children are unable to understand until they are about two years old.
‘This implies that elephants may be capable of recognising themselves as separate from objects or their environment.
‘This means that they may have a level of self-understanding, coupled with their passing of the mirror test, which is quite rare in the animal kingdom.’
The study, largely funded by a Newton International Fellowship from the Royal Society awarded to Dr Plotnik, is published in the journal Scientific Reports. | <urn:uuid:57b72360-63a9-4f28-afc4-3e304c8e47e9> | 3.28125 | 655 | News Article | Science & Tech. | 37.945507 | 95,593,638 |
Welcome to iGEM 2018!
Your team has been approved and you are ready to start the iGEM season!
About our project
An overall increase in industrialization has subsequently led to an overall increase in the carbon footprint, the major component being CO2 which in turn led to global warming. Among other ill effects of industrialization, the one that has garnered a lot of attention is what we call Ocean Acidification. It is also known as "the other CO2 problem" and that's where our engineered microbe jumps in.
Geology reports suggest that between the years 1751 to 1996 there has been an increase of H+ ions of upto 30%. Apart from that, the overall pH has been decreased from 8.25 to 8.14. Increasing acidity is directly linked to having potentially harmful consequences for marine organisms, such as depressing metabolic rates and immune responses in some organisms, and causing the worst cases of coral bleaching.
"If we continue emitting CO2 at the same rate, by 2100 ocean acidity will increase by about 150 percent, a rate that has not been experienced for at least 400,000 years."
-United Kingdom Ocean Acidification Research Programme, 2015
Our engineered vibrio will interact with its surrounding environment to give real-time H+ data which is then used by pH-sensitive NhaA and CadA promoters which give maximum expression at pH 8.5 and pH 7 respectfully; after which the expression is down-regulated. Within this 1.5 pH window, our biobricks are designed such that the carbonic anhydrase genes bring about a reduction in ocean acidification. Once the pH is stabilized, repressor proteins are expressed which block the carbonic anhydrase expression so that no more shuttling of H+ takes place thereby saving marine flora and fauna from any more damage. | <urn:uuid:7e6dafd6-51b5-4936-8271-cbf2a6a055fb> | 3.25 | 377 | About (Org.) | Science & Tech. | 45.56982 | 95,593,656 |
Two alternative ways of modelling the field are shown in the following two examples.We shall use the description of the field in terms of field lines, as shall be explained in detail below.
In the first case, it may be observed how the field accompanies the charge with a radial shape all across the space, even after the collision has taken place. This means that any point in space "knows" instantaneously any velocity change of the charge. Actually, this information travels at the speed of light in vacuum. Only after a finite time (given by the distance to the charge divided by the speed of light) a point located at a given distance of the charge will "know" that the velocity of the charge has changed. This can be correctly appreciated in the second example. the information propagates as a pulse (kink in the field lines) that travels at the speed of light away from the charge. This is the basis of the radiation phenomenon, which takes place whenever a charge is accelerated. | <urn:uuid:ab1ce83a-f35e-4a67-a918-639474e427f8> | 3.5 | 201 | Academic Writing | Science & Tech. | 48.642701 | 95,593,658 |
That topic ¯ DNA wires and their potential use in identifying people at risk for certain diseases ¯ is the focus of a plenary talk here today during the 244th National Meeting & Exposition of the American Chemical Society, the world's largest scientific society. The meeting, which features about 8,600 reports with an anticipated attendance of 14,000 scientists and others continues here through Thursday.
"DNA is a very fragile and special wire," said Jacqueline K. Barton, Ph.D., who delivered the talk. "You're never going to wire a house with it, and it isn't sturdy enough to use in popular electronic devices. But that fragile state is exactly what makes DNA so good as an electrical biosensor to identify DNA damage."
Barton won the U.S. National Medal of Science, the nation's highest honor for scientific achievement, for discovering that cells use the double strands of the DNA helix like a wire for signaling, which is critical to detecting and repairing genetic damage. She is a professor of chemistry and is chair of the division of chemistry and chemical engineering at the California Institute of Technology in Pasadena.
Damage is constantly occurring to DNA, Barton explained ¯ damage that skin cells, for instance, receive from excessive exposure to sunlight or that lung cells get hit with from carcinogens in cigarette smoke. Cells have a natural repair system in which special proteins constantly patrol the spiral-staircase architecture of DNA. They monitor the 3 billion units, or "base pairs," in DNA, looking for and mending damage from carcinogens and other sources.
Barton and other scientists noticed years ago that the DNA architecture chemically resembles the solid-state materials used in transistors and other electronic components. And DNA's bases, or units, are stacked on top of each other in an arrangement that seemed capable of conducting electricity.
"It's like a stack of copper pennies," said Barton. "And when in good condition and properly aligned, that stack of copper pennies can be conductive. But if one of the pennies is a little bit awry ¯ if it's not stacked so well ¯ then you're not going to be able to get good conductivity in it. But if those bases are mismatched or if there is any other damage to the DNA, as can happen with damage that leads to cancer, the wire is interrupted and electricity will not flow properly."
Barton's team established that the electrons that comprise a flow of electricity can move from one end of a DNA strand to the other, just as they do through an electrical wire. In one recent advance, the team was able to send electricity down a 34-nanometer-long piece of DNA. That might not sound like much — a nanometer is one-tenth the width of a human hair. But that is just the right scale for use in medical diagnostic devices and biosensors to pick up on mutations, or changes, in DNA that could lead to cancer and other diseases.
Barton's research suggested that DNA uses its electrical properties to signal repair proteins that fix DNA damage. If the DNA is no longer conducting electricity properly, that would be a signal for repair proteins to do their thing. Barton's team is applying that knowledge in developing "DNA chips," devices that take advantage of DNA's natural electrical conductivity and its ability to bind to other strands of DNA that have a complementary sequence of base units, and thus probe that sequence for damage. Such a DNA chip would help diagnose disease risk by changes in electrical conductivity resulting from mutations or some other damage.Other plenary talks featured at the 244th National Meeting & Exposition of the American Chemical Society include:
John T. Santini, Ph.D., "Multireservoir drug therapies … from science to startups"
Barton and colleagues acknowledge funding from the National Institutes of Health.
The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 164,000 members, ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.
To automatically receive news releases from the American Chemical Society, contact firstname.lastname@example.org.
Note to journalists: Please report that this research was presented at a meeting of the American Chemical Society.Abstract
Michael Bernstein | EurekAlert!
O2 stable hydrogenases for applications
23.07.2018 | Max-Planck-Institut für Chemische Energiekonversion
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
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The molecular components of mammalian circadian clocks are elusive. We have isolated a human gene termed RIGUI that encodes a bHLH/PAS protein 44% homologous to Drosophila period. The highly conserved mouse homolog (m- rigui) is expressed in a circadian pattern in the suprachiasmatic nucleus (SCN), the master regulator of circadian clocks in mammals. Circadian expression in the SCN continues in constant darkness, and a shift in the light/dark cycle evokes a proportional shift of m-rigui expression in the SCN. m-rigui transcripts also appear in a periodic pattern in Purkinje neurons, pars tuberalis, and retina, but with a timing of oscillation different from that seen in the SCN. Sequence homology and circadian patterns of expression suggest that RIGUI is a mammalian orthology of the Drosophila period gene, raising the possibility that a regulator of circadian clocks is conserved.
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Text Assets are a format for imported text files. When you drop a text file into your Project Folder, it will be converted to a Text AssetAny media or data that can be used in your game or project. An asset may come from a file created outside of Unity, such as a 3D model, an audio file or an image. You can also create some asset types in Unity, such as an Animator Controller, an Audio Mixer or a Render Texture. More info
See in Glossary. The supported text formats are:
Note that script files are also considered text assets for the purposes of using the AssetDatabase.FindAssets function, so they will also be included in the list of results when this function is used with the “t:TextAsset” filter.
|TextA non-interactive piece of text to the user. This can be used to provide captions or labels for other GUI controls or to display instructions or other text. More info
See in Glossary
|The full text of the asset as a single string.|
The Text Asset is a very specialized use case. It is extremely useful for getting text from different text files into your game while you are building it. You can write up a simple .txt file and bring the text into your game very easily. It is not intended for text file generation at runtime. For that you will need to use traditional Input/Output programming techniques to read and write external files.
Consider the following scenario. You are making a traditional text-heavy adventure game. For production simplicity, you want to break up all the text in the game into the different rooms. In this case you would make one text file that contains all the text that will be used in one room. From there it is easy to make a reference to the correct Text Asset for the room you enter. Then with some customized parsing logic, you can manage a large amount of text very easily.
A special feature of the text asset is that it can be used to store binary data. By giving a file the extension .bytes it can be loaded as a text asset and the data can be accessed through the bytes property.
For example put a jpeg file into the Resources folder and change the extension to .bytes, then use the following script code to read the data at runtime:
//Load texture from disk TextAsset bindata= Resources.Load("Texture") as TextAsset; Texture2D tex = new Texture2D(1,1); tex.LoadImage(bindata.bytes);
Please notice that files with the .txt and .bytes extension will be treated as text and binary files, respectively. Do not attempt to store a binary file using the .txt extension, as this will create unexpected behaviour when attempting to read data from it.
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Number theory is the study of the integers (i.e. whole numbers) and related objects. Topics studied by number theorists include the problem of determining the distribution of prime numbers within the integers and the structure and number of solutions of systems of polynomial equations with integer coefficients. Many problems in number theory, while simple to state, have proofs that involve apparently unrelated areas of mathematics. A beautiful illustration is given by the use of complex analysis to prove the “Prime Number Theorem,” which gives an asymptotic formula for the distribution of prime numbers. Yet other problems currently studied in number theory call upon deep methods from harmonic analysis.
In addition, conjectures in number theory have had an impressive track record of stimulating major advances even outside the subject. For example, attempts to prove “Fermat’s Last Theorem” resulted in the development of large areas of algebra over the course of three centuries, and its recent proof involved a profound unifying force in modern mathematics known as the Langlands program.
At Duke, number theory is represented by Jayce Getz, Heekyoung Hahn, and Lillian Pierce, with Richard Hain, Leslie Saper and Chad Schoen working in related areas. Our specialties include analytic number theory, the Langlands program, the geometry of locally symmetric spaces, arithmetic geometry and the study of algebraic cycles.
Professor of Computer Science
Keywords in this area
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Authors: Cres Huang
Atomic electron transition appears leaping from one energy level to another. The issue is, atomic particles are too small and too fast for our detectors to recognize their action and identity. I believe it is due to the sensors can only detect and register the repeated trajectory. Particle would have to revolving on the same orbit long enough. Otherwise, it would not trigger the reaction of the detectors. Transitional trajectory is short, and it does not repeat. It can not be detected, hence, jump.
Comments: 4 Pages.
[v1] 2017-12-24 00:01:29
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Lidar-derived Canopy Height Models (CHMs) are commonly used for extracting relevant forest information. Often irregular height variations – also called data pits or simply pits – are present in the CHM. These pits typically appear when the first Lidar return is far below the canopy which tends to happen for two reasons. The first reason is that a laser beam deeply penetrates into the branches and the foliage before producing the first return (Persson et al., 2002). The second reason is multiple laser beams – possibly from different flight lines – produce their first return in close horizontal proximity but with a great height difference because they “see” the canopy or the ground from different angles (Leckie et al., 2003). These pits hamper the correct extraction of forestry metrics from the CHM. Previous studies recommend applying smoothing methods such as a median filter or a Gaussian filter to reduce the data pits. However, smoothing modifies the CHM leading to subsequent misinterpretation of the biophysical tree parameters (Solberg et al., 2006).
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Chapter 33. Using the FAT Filesystem
The FAT filesystem is accessed through the FILEIO package and responds
to all the standard filesystem functions such as
write(). To use
these operations the filesystem must first be mounted.
A FAT filesystem may be mounted using the
function. The following is an example of how to mount a FAT filesystem:
err = mount( "/dev/hd0/1", "/disk0", "fatfs:sync=write" );
This function call will mount the first partition of hard disk 0 (see
the documentation on the DISKIO package for a full description of the
device name format). The root of this disk can then be accessed
with the name "/disk0". The
mount() function will
return zero if the mount succeeded, or -1 if it failed for any reason,
for example if the partition does not exist, or the filesystem is not
in FAT format.
The options after the colon in the filesystem name are passed to the filesystem to control various aspects of the filesystem. The options currently supported are:
This option controls the synchronization behaviour of the block cache. If omitted then the cache is run on an entirely write-back basis and blocks are only written back to disk when they need to be replaced with new data, when
sync()is called, or the filesystem is unmounted. This is generally the most efficient mode, but is prone to losing data or corrupting the filesystem if power is lost while the filesystem is mounted.
If this option is set to "write" then the cache is operated on a write-back basis and every block update is written immediately back to disk. This is the least efficient mode since any extension to a file may result in several blocks being written back to disk. It does, however, keep the filesystem up to date on disk.
If this option is set to "close" then the cache is only written back to disk whenever a file is closed. Note that this causes the entire cache to be written, not just those blocks associated with the file being closed. In terms of efficiency, this is a good compromise between performance and safety.
- This is a stand-alone option which causes the filesystem to be mounted read-only. The effect of this is to prevent the filesystem writing anything back to the disk. Under normal circumstances this cannot be guaranteed for a normal mount, even when files are only read, since the filesystem may need to update the access time for files that have been read.
When finished with, a filesystem may be unmounted using the
umount() function. The following would unmount
the filesystem mounted above:
err = umount( "/disk0" );
It is important to unmount any removable devices before removing them, otherwise there is no guarantee that all cached data blocks will have been written to disk. The same is true of resetting the system before unmounting non-removable devices.
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More green for greener satellites
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Long Term Monitoring of Vegetation Greenness from Satellites Ranga Myneni
Ranga Myneni • Oct 20, 2017
What are the causes of the greening observed in Arctic tundra regions during the period of satellite-based observations ?
Oct 28, 2017
The Galilean Satellites
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A View from Emerging Technology from the arXiv
Ice XV Discovered
A long-predicted phase of frozen water called ice XV has finally been prepared.
Freeze water and you’ll get ice. But not all ice is created equal.
Ice can form a surprising number of crystalline and noncrystalline structures, depending on the temperature and pressure at which it forms and the way that conditions change after it has frozen.
Over the years, ice scientists have created and characterized some 15 different kinds of crystalline ice and three different kinds of amorphous noncrystalline ice. Almost all the ice on Earth is of type Phase lh (hexagonal crystalline), although there is a small amount of Phase lc (cubic crystalline) lying around here and there.
The others come in crystals of all shapes and sizes, such as rhombic, tetragonal, monoclinic, etc., but have only ever been seen in the laboratory, although they may well play a role in the geochemistry of comets and icy planets and moons.
But in all this time, one phase of ice has eluded everybody. Ice XV has long been predicted to exist at temperatures of between 108 and 180 kelvins and at a pressure of 1.1 gigapascals.
Now Christoph Salzmann at the University of Oxford and acquaintances have created the stuff for the first time and say that its properties differ significantly from those predicted. In particular, ice XV is antiferroelectric rather than ferroelectric, as had been predicted.
I guess that makes it slightly less interesting than had been hoped. Ferroelectric materials usually have interesting electrical properties, such as the ability to form capacitors. That would have given planetary geologists something to think about, but now they can rest easy.
Ref: http://arxiv.org/abs/0906.2489: Ice XV: A New Thermodynamically Stable Phase of Ice
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The Coherence of Light
Interference and diffraction of light are phenomena known from various experiments. Whereas a dark room used to be necessary to observe interference and diffraction with the use of a monochromatic spectral light source, it is now possible to observe them in an ordinary room in daylight by using a laser light source. The phenomena of interference and diffraction of light are due to the wave nature of light, which will be discussed in this chapter.
KeywordsAutocorrelation Function Interference Pattern Coherence Length Light Wave Interference Fringe
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L. S. Berg, 1937
|Wikimedia Commons has media related to Beloniformes.|
- Adrianichthyidae (ricefish and medakas)
- Belonidae (needlefish)
- Exocoetidae (flyingfishes)
- Hemiramphidae (halfbeaks)
- Scomberesocidae (sauries)
- Zenarchopteridae (viviparous halfbeaks)
With the exception of the Adrianichthyidae, these are streamlined, medium-sized fishes that live close to the surface of the water, feeding on algae, plankton, or smaller animals including other fishes. Most are marine, though a few needlefish and halfbeaks inhabit brackish and fresh waters.
The order is sometimes divided up into two suborders, the Adrianichthyoidei and the Belonoidei. The Adrianichthyoidei contain only a single family, the Adrianichthyidae. Originally, the Adrianichthyidae were included in the Cyprinidontiformes and assumed to be closely related to the killifish, but a closer relationship to the beloniforms is indicated by various characteristics including the absence of the interhyal, resulting in the upper jaw being fixed or not protrusible. The Belonoidei may also be further subdivided into two superfamilies, the Scomberesocoidea and the Exocoetoidea. The Scomberesocoidea contain the Belonidae and Scomberesocidae, while the Exocoetoidea comprise the Exocoetidae and Hemiramphidae. However, newer evidence shows the flyingfishes are nested within the halfbeaks, and the needlefish and sauries are nested within the subfamily Zenarchopterinae of the family Hemiramphidae, which has been recognized as its own family. The sauries are also nested within the family Belonidae.
The beloniforms display an interesting array of jaw morphologies. The basal condition in the order excluding the ricefishes is an elongated lower jaw in juveniles and adults as represented in halfbeaks. In the needlefish and sauries, both jaws are elongated in the adults; the juveniles of most species develop through a "halfbeak stage" before having both jaws elongated. The elongated lower jaw is lost in adults and is lost in most juveniles in the flyingfishes and some halfbeak genera.
Timeline of genera
- Froese, R. and D. Pauly. Editors. "Order Summary for Beloniformes". FishBase. Retrieved 2007-02-10.
- Helfman G., Collette B., & Facey D.: The Diversity of Fishes, Blackwell Publishing, pp 274-276, 1997, ISBN 0-86542-256-7
- Nelson, Joseph S. (2006). Fishes of the World. John Wiley & Sons, Inc. ISBN 0-471-25031-7.
- Lovejoy, N; Iranpour, M; Collette, B (2004). "Phylogeny and Jaw Ontogeny of Beloniform Fishes". Integrative and Comparative Biology. 44 (5): 366–377. doi:10.1093/icb/44.5.366. PMID 21676722.
- Sepkoski, Jack (2002). "A compendium of fossil marine animal genera". Bulletins of American Paleontology. 364: 560. Archived from the original on 2011-07-23. Retrieved 2011-05-17. | <urn:uuid:47902731-8a8f-41c0-848e-897edf5f2d2b> | 2.984375 | 756 | Knowledge Article | Science & Tech. | 34.927753 | 95,593,751 |
John Archibald Wheeler (1911-2008) was a scientist-philosopher who introduced the concept of wormholes and coined the term “black hole”. He pioneered the theory of nuclear fission with Niels Bohr and introduced the S-matrix (the scattering matrix used in quantum mechanics). Wheeler devised a concept of quantum foam; a theory of “virtual particles” popping in and out of existence in space (similarly, he conceptualized foam as the foundation of the fabric of the universe).
Besides his extraordinary contributions to the field of theoretical physics, Wheeler inspired many aspiring young scientists, including some of the greats of the 20th century. Among his doctoral students were Richard Feynman, a Nobel Prize laureate, with whom he coauthored the “Wheeler-Feynman absorber theory”; Hugh Everett, who proposed the many worlds interpretation; Kip Thorne, who predicted the existence of red supergiant stars with neutron-star cores; Jacob Bekenstein, who formulated black hole thermodynamics; Charles Misner, who discovered a mathematical spacetime called Misner space; Arthur Wightman, the originator of Wightman axioms; and Benjamin Schumacher, who invented the term “qubit” and is known for the “Schumacher compression”. The list could go on.
Wheeler had a reputation pushing his students into a place where logical thought would not necessarily take them. Former student Richard Feynman, to Kip Thorne, declared, “Some people think that Wheeler’s gotten crazy in his later years, but he’s always been crazy!” [Reference: Princeton] Wheeler was willing to make a fool of himself, to go anywhere, talk to anybody, and ask any question that would get him closer to understanding “how things are put together.”
Wheeler believed that the real reason universities have students is to educate the professors. But to be educated by the students, a professor had to ask good questions. “You try out your questions on the students”, he wrote, “If there are questions that the students get interested in, then they start to tell you new things and keep you asking more new questions. Pretty soon you have learned a great deal.” [Reference: Cosmic Search Vol. 1 No. 4]
Wheeler had a fantastic sense of humor. Often he engaged in Koan-like expressions that puzzled and amused his listeners. He saw beauty in strangeness and actively sought it out. He declared, “If you haven’t found something strange during the day, it hasn’t been much of a day.”
Wheeler divided his own life into three parts. The first part he called “Everything is Particles.” The second part was “Everything is Fields.” And the third part, which Wheeler considered the bedrock of his physical theory, he called “Everything is Information.”
EVERYTHING IS PARTICLES:
John Archilald Wheeler was born on July 9, 1911, in Jacksonville, Florida, into a family of librarians. At 16, he won a scholarship to Johns Hopkins University. He graduated five years later with a Ph.D in physics. A year later he got engaged to Janette Hegner. They stayed married for 72 years.
In 1933 in an application for the National Research Council Fellowship to go to Copenhagen and work with Neils Bohr, Wheeler wrote: “I want to go to work with Neils Bohr because he sees further than any man alive.” Bohr and Wheeler published their first paper in the late 1930s, explaining nuclear fission in terms of quantum physics. They argued that the atomic nucleus, containing protons and neutrons, is like a drop of liquid, which starts vibrating and elongating into a peanut shape when a neutron emitted from another disintegrating nucleus collides with it. As a result, the peanut shaped atomic nucleus snaps into two.
In 1938 Wheeler started teaching at Princeton University. In 1941 he interrupted his academic work to join the Manhattan Project team (which included the likes of Feynman, Bohr and Albert Einstein – with Marie Curie helping lay out the blueprints) in building an atomic bomb. Wheeler considered it his duty to help with the war effort, but the atomic bomb wasn’t ready in time to end the war and save his beloved brother, who died in Italy in 1944.
After the war ended, Wheeler returned to Princeton and taught Einstein’s general theory of relativity, which at a time was not considered a “respectable” field of physics. Wheeler’s classes were exciting – one of his tricks was to write on chalkboards with both hands. He frequently took his students to Albert Einstein’s house in Princeton for discussions over a cup of tea.
EVERYTHING IS FIELDS:
Wheeler co-wrote the most influential textbook on general relativity with Charles W. Misner and Kip Thorne. It was called Gravitation. While working on mathematical extensions to the theory, Wheeler described hypothetical “tunnels” in space-time which he called “wormholes”. He was not the first scientist to think of the possibility of wormholes, or even black holes, but he established the idea. In this regard, it’s worth noting that Democritus, an ancient Greek philosopher, suggested that matter was composed of atoms, which was “mainstreamed” by John Dalton’s discovery of atoms 2000 years later. In 1784, John Mitchell, a Yorkshire clergyman, suggested that light was subject to the force of gravity long before Einstein proved it.
After the publication of the theory of General Relativity in 1916, in which Albert Einstein predicted the existence of black holes, in 1967 John Wheeler named them. Nigel Calder calls them “awesome engines of quasars and active galaxies.” We now have multiple variations of the original concept: charged black holes, rotating black holes, stationary black holes, supermassive black holes, stellar black holes, miniature black holes.
EVERYTHING IS INFORMATION:
Let’s get to Wheeler’s three-part life- story, the last part he called “Everything is Information”.
In the final decades of his life, the question that intrigued Wheeler most was: “Are life and mind irrelevant to the structure of the universe, or are they central to it?” He suggested that the nature of reality was revealed by the bizarre laws of quantum mechanics. According to the quantum theory, before the observation is made, a subatomic particle exists in several states, called a superposition (or, as Wheeler called it, a ‘smoky dragon’). Once the particle is observed, it instantaneously collapses into a single position.
Wheeler suggested that reality is created by observers and that: “no phenomenon is a real phenomenon until it is an observed phenomenon.” He coined the term “Participatory Anthropic Principle” (PAP) from the Greek “anthropos”, or human. He went further to suggest that “we are participants in bringing into being not only the near and here, but the far away and long ago.” [Reference: Radio Interview With Martin Redfern]
This claim was considered rather outlandish until his thought experiment, known as the “delayed-choice experiment,” was tested in a laboratory in 1984. This experiment was a variation on the famous “double-slit experiment” in which the dual nature of light was exposed (depending on how the experiment was measured and observed, the light behaved like a particle (a photon) or like a wave).
Unlike the original “double-slit experiment”, in Wheeler’s version, the method of detection was changed AFTER a photon had passed the double slit. The experiment showed that the path of the photon was not fixed until the physicists made their measurements. The results of this experiment, as well as another conducted in 2007, proved what Wheeler had always suspected – observers’ consciousness is required to bring the universe into existence. This means that a pre-life Earth would have existed in an undetermined state, and a pre-life universe could only exist retroactively.
A UNIVERSE ‘FINE-TUNED’ FOR LIFE:
These conclusions lead many scientists to speculate that the universe is fine-tuned for life. This is how Wheeler’s Princeton colleague, Robert Dicke, explained the existence of our universe:
“If you want an observer around, and if you want life, you need heavy elements. To make heavy elements out of hydrogen, you need thermonuclear combustion. To have thermonuclear combustion, you need a time of cooking in a star of several billion years. In order to stretch out several billion years in its time dimension, the universe, according to general relativity, must be several years across in its space dimensions. So why is the universe as big as it is? Because we are here!”
[Reference: Cosmic Search Vol. 1 No. 4]
Stephen Hawking has also noted: “The laws of science, as we know them at present, seem to have been very finely adjusted to make possible the development of life.” Fred Hoyle, in his book Intelligent Universe, compares “the chance of obtaining even a single functioning protein by a chance combination of amino acids to a star system full of blind men solving Rubik’s Cube simultaneously.”
Physicist Andrei Linde of Stanford University adds: “The universe and the observer exist as a pair. I cannot imagine a consistent theory of the universe that ignores consciousness.” [Reference: “Biocentrism: How Life and Consciousness are the Keys to Understanding the Universe“]
Wheeler, always an optimist, believed that one day we would have a clear understanding of the origin of the universe. He had “a sense of faith that it can be done.” “Faith”, he wrote, “is the number one element. It isn’t something that spreads itself uniformly. Faith is concentrated in few people at particular times and places. If you can involve young people in an atmosphere of hope and faith, then I think they’ll figure out how to get the answer.”
Wheeler died of pneumonia on April 13, 2008, at age 96. His whole life he searched for answers to philosophical questions about the origin of matter, the nature of information and the universe. “We are no longer satisfied with insights into particles, or fields of force, or geometry, or even space and time,” he wrote in 1981, “Today we demand of physics some understanding of existence itself.” [Reference: “The Voice of Genius: Conversations with Nobel Scientists and Other Luminaries”]
Let’s hope that young scientists will continue to be encouraged by these words and will push the boundaries of human imagination beyond its limits, and maybe even find the elusive final theory – a Theory of Everything. | <urn:uuid:6257b132-2db1-45df-9c07-a72f9a5fa461> | 3.453125 | 2,334 | Knowledge Article | Science & Tech. | 40.566703 | 95,593,752 |
|This article is a stub. Please help Sciencemadness Wiki by expanding it, adding pictures, and improving existing text.
| IUPAC name
| Other names
|Molar mass||74.12 g/mol|
|Appearance||Colorless solid (<25 °C) or liquid (>25 °C)|
|Density||0.7886 g/cm3 (at 20 °C)|
|Melting point||25.81 °C (78.46 °F; 298.96 K)|
|Boiling point||82.3 °C (180.1 °F; 355.4 K)|
|Solubility|| Miscible with diethyl ether, ethanol, isopropanol|
Soluble in chloroform
|Vapor pressure||4.1 kPa (at 20 °C)|
Std enthalpy of
|Safety data sheet||ScienceLab|
|Flash point||11 °C|
|Lethal dose or concentration (LD, LC):|
LD50 (Median dose)
| 3559 mg/kg (rabbit, oral)|
3500 mg/kg (rat, oral)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
tert-Butanol or tert-Butyl alcohol (TBA), also known as 2-methylpropan-2-ol (2M2P), is the simplest tertiary alcohol, with a formula of (CH3)3COH (sometimes shortened to t-BuOH). One of the most interesting characteristics of t-BuOH is that it can be a clear liquid or a colorless solid depending on the ambient temperature and season, with a melting point around 25 °C.
Being a tertiary alcohol, tert-butanol cannot be oxidized to an aldehyde or ketone, like primary or secondary alcohols can.
tert-Butanol is a colorless solid at standard conditions, but has a very high melting point for a simple alcohol, of only 25.8 °C. It's boiling point is 82.3 °C. t-BuOH is miscible with water and has a camphor-like smell.
t-BuOH is sold by various chemical suppliers.
It can also be found as fuel additive, though the percentage is small.
Small amounts are sometimes added in rubbing alcohol as a denaturing agent.
tert-Butanol can be made via acid catalyzed hydrolysis of methyl tert-butyl ether.
A more complex way is by reacting acetone with methylmagnesium halide
tert-Butanol poses low toxicity, though it can be irritant. It is also flammable.
tert-Butanol should be stored in closed bottles, preferably glass. If the temperature inside the storage area drops below 25 °C, such as during cold seasons, rain or night, t-BuOH will freeze. This is not usually a problem, as it does not expand upon freezing and is also less volatile when solid, but getting it out of the bottle may become frustrating.
tert-Butanol can be safely burned, either pure or dissolved in a more flammable solvent. It can also be destroyed with Fenton's reagent, though this is not always necessary. | <urn:uuid:17553d58-1aaf-4e60-a2fc-494bcaff42dd> | 2.890625 | 704 | Knowledge Article | Science & Tech. | 65.92137 | 95,593,764 |
Michael Bakke is a Professor of Mathematics at Bielefeld University, Germany. He has been working on the theory of quasicrystals since 1987 and during that time organised several international meetings on the mathematics of aperiodic order, including workshops at Banff, Oberwolfach and the Erwin Schrdinger Institute in Vienna.
Uwe Grimm is a Professor of Mathematics in the Faculty of Mathematics, Computing and Technology at the Open University, Milton Keynes. He has been working on the mathematics and physics of aperiodically ordered systems for nearly 20 years. He co-organised the 6th International Conference on Aperiodic Crystals in Liverpool in 2009 and is a member of the Commission on Aperiodic Crystals of the International Union of Crystallography.
This practical, friendly guide focuses on critical concepts taught in a typical geometry course, from the properties of triangles, parallelograms, circles, and cylinders, to the skills and strategies you need to write geometry proofs. Geometry Essentials For Dummies is perfect for cramming or doing homework, or as a reference for parents helping kids study for exams.
Get down to the basics — get a handle on the basics of geometry, from lines, segments, and angles, to vertices, altitudes, and diagonals
Conquer proofs with confidence — follow easy-to-grasp instructions for understanding the components of a formal geometry proof
Take triangles in strides — learn how to take in a triangle's sides, analyze its angles, work through an SAS proof, and apply the Pythagorean Theorem
Polish up on polygons — get the lowdown on quadrilaterals and other polygons: their angles, areas, properties, perimeters, and much more
Open the book and find:
Plain-English explanations of geometry terms
Tips for tackling geometry proofs
The seven members of the quadrilateral family
Straight talk on circles
Essential triangle formulas
The lowdown on 3-D: spheres, cylinders, prisms, and pyramids
Ten things to use as reasons in geometry proofs
Core concepts about the geometry of shapes and geometry proofs
Critical theorems, postulates, and definitions
The principles and formulas you need to know | <urn:uuid:5e928d25-b3b3-465c-8540-21d2025af017> | 2.984375 | 459 | Product Page | Science & Tech. | 2.930634 | 95,593,799 |
A gene that signals a yeast cell to make bread rise and mice to eat a better diet also helps selectively silence the immune system, researchers have found.
The finding may help explain how a mother avoids rejecting a genetically foreign fetus and provides a new target for treatments to help the immune system ignore other desirables like a transplanted organ. “Think of this like a radio transmitter and a receiver,” says Dr. David H. Munn, pediatric hematologist-oncologist at the Medical College of Georgia and lead author of the study in the May issue of Immunity.
The transmitter is indoleamine 2,3-dioxygenase, or IDO, an enzyme particularly expressed in places such as the gastrointestinal tract and tonsils where the immune system routinely meets up with foreign substances it might want to ignore. Drs. Munn, Andrew L. Mellor and Simon J. Conway published a Science article in 1998 showing IDO’s role in protecting the fetus from rejection by the mother’s immune system during pregnancy. Later they learned that tumors and persistent viruses such as HIV may hijack this mechanism to shield themselves from immune attack. They knew IDO degraded tryptophan, an amino acid essential to the survival of T cells. They weren’t so certain what happened at the receiving end.
Toni Baker | EurekAlert!
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
Pollen taxi for bacteria
18.07.2018 | Technische Universität München
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
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18.07.2018 | Health and Medicine | <urn:uuid:73f6df68-e478-415c-ad8d-f4d556eb508c> | 3.125 | 911 | Content Listing | Science & Tech. | 41.672387 | 95,593,817 |
Japan has revealed ambitious plans to put an astronaut on the Moon around 2030 in new proposals from the country's space agency.
This is the first time the Japan Aerospace Exploration Agency (JAXA) has said it aims to send an astronaut beyond the International Space Station, an agency spokeswoman told AFP on Friday. The idea is to first join a NASA-led mission in 2025 to build a space station in the moon's orbit, as part of a longer-term effort by NASA to reach Mars.
Tokyo hopes that contributing to the multinational mission and sharing Japanese technology will land it a coveted spot at the station, from which it could eventually send an astronaut to the Moon, the spokeswoman said. The plan was presented at an education ministry panel this week, with a more formal blueprint expected next year, according to public broadcaster NHK.
The announcement comes as China and India develop their space programmes. In November, China's Shenzhou-11 spacecraft returned to Earth, bringing home two astronauts from the rising power's longest-ever orbital mission. Beijing has also unveiled illustrations of a Mars probe and rover it aims to send to the Red Planet at the end of the decade.
NASA and other global space agencies are working hard on sending astronauts to Mars by the 2030s. In March, the US Congress passed a bill, signed by President Donald Trump, directing NASA to send a manned mission to Mars in 2033. | <urn:uuid:2813a463-f6a5-4cd6-83ac-0f9f00a0cac9> | 2.8125 | 285 | News Article | Science & Tech. | 46.473002 | 95,593,828 |
This periodic table of elements provides comprehensive data on the chemical elements including scores of properties, element names in many languages and most known nuclides (Isotopes). Below the table there is a "Periodic Table Sorted By" section with links that will sort chemical elements by various properties. Each element on the table below links to a detailed page for that element.
|Last updated: Dec. 2, 2011|
|1||1 H||2 He|
|2||3 Li||4 Be||5 B||6 C||7 N||8 O||9 F||10 Ne|
|3||11 Na||12 Mg||13 Al||14 Si||15 P||16 S||17 Cl||18 Ar|
|4||19 K||20 Ca||21 Sc||22 Ti||23 V||24 Cr||25 Mn||26 Fe||27 Co||28 Ni||29 Cu||30 Zn||31 Ga||32 Ge||33 As||34 Se||35 Br||36 Kr|
|5||37 Rb||38 Sr||39 Y||40 Zr||41 Nb||42 Mo||43 Tc||44 Ru||45 Rh||46 Pd||47 Ag||48 Cd||49 In||50 Sn||51 Sb||52 Te||53 I||54 Xe|
|6||55 Cs||56 Ba||57 La||1||72 Hf||73 Ta||74 W||75 Re||76 Os||77 Ir||78 Pt||79 Au||80 Hg||81 Tl||82 Pb||83 Bi||84 Po||85 At||86 Rn|
|7||87 Fr||88 Ra||89 Ac||2||104 Rf||105 Db||106 Sg||107 Bh||108 Hs||109 Mt||110 Ds||111 Rg||112 Cn||114 Uuq||116 Uuh||118 Uuo|
|6||1||58 Ce||59 Pr||60 Nd||61 Pm||62 Sm||63 Eu||64 Gd||65 Tb||66 Dy||67 Ho||68 Er||69 Tm||70 Yb||71 Lu|
|7||2||90 Th||91 Pa||92 U||93 Np||94 Pu||95 Am||96 Cm||97 Bk||98 Cf||99 Es||100 Fm||101 Md||102 No||103 Lr|
|New IUPAC system|
|Old IUPAC system (primarily in Europe)|
|CAS system (primarily in North America)|
|Physical States etc.|
States are at normal temperature and pressure.
|Xx||Liquids||Xx||Synthetically prepared elements|
Our policy is to only create individual element pages for elements on our periodic table that have been officially recognized and named by the International Union of Pure and Applied Chemists (IUPAC). Likewise we only list unnamed elements on our table above whose discovery has been tentatively recognized by IUPAC. Thus at this point in time we have not created individual element pages for elements 114 and above as they have not been officially named. Likewise even though some scientists have claimed to have isolated elements 113 and 115 we do not list these two elements because their discovery has not yet been acknowledged by IUPAC.
The "discovery" of element 118 is still very much in debate. It was reportedly isolated in 1999 by the Ninov et al. Berkeley collaboration, but that report was retracted in 2002. In Oct. 2006 it was again reportedly isolated by scientists from the Lawrence Livermore National Laboratory and their Russian partners at the Dubna nuclear research center in Russia, but IUPAC has not yet commented on this.
On December 1st 2011, the IUPAC announced the proposed names for elements 114 and 116. Element 114 would be named flerovium with the symbol Fl, while element 116 would be named livermorium with the symbol Lv. There will be a five month comment period for the new names. If all goes well the names will become official in May of 2012.
Reference resources used to compile and verify data used to generate these pages.
If you need to cite this page, you can copy this text:
Kenneth Barbalace. Periodic Table of Elements. EnvironmentalChemistry.com. 1995 - 2018. Accessed on-line: 7/20/2018 | <urn:uuid:cad9a2a2-962c-4b28-b572-83112f854d6b> | 3.171875 | 923 | Knowledge Article | Science & Tech. | 82.546976 | 95,593,838 |
Carolyn Malmstrom, assistant professor of plant biology at Michigan State University, isolated historical viral RNA sequences in native and invasive grasses revealing a complex picture of struggles of species, interactions of insects and implications for the ways viruses behave today. The findings are reported in the Oct. 16th edition of the Journal of Ecology.
“This work points out that the virus world does have an active, long-term role in nature, not just in agriculture,” Malmstrom said. “We very much need to understand how viruses can move and influence our crops. If we care about our crops, we need to care about what’s happening in nature.”
When living in northern California, Malmstrom noticed that a walk through grasslands dominated by nonnative annual plants meant getting covered in aphids, an infestation that wasn’t seen in typically perennial grasses indigenous to the area.
It made her wonder what the differences were – and what that meant to the overall health of those ecosystems.
Those questions ultimately led to viruses, which can be spread among plants by aphids the way mosquitoes spread disease among humans. Malmstrom explained little is known about viruses in nature – that’s usually a discussion reserved for agricultural crops. But recent advances in molecular techniques have unveiled natural systems teeming with viruses – and thus raising the question of what the impact of those viruses is.
“We’ve always assumed viruses largely are manifested in agricultural systems, because the system is unbalanced due to human interaction,” Malmstrom said. “But now we are understanding viruses are more common in nature than people realize – and that there’s a whole class of biological interactions going on out there that we know hardly anything about.”
This paper deals with historical virus ecology – understanding how viruses have affected grasslands years ago. The team examined dried California grasses in plant collections from the early 1900s. Unprotected, RNA typically degenerates quickly, but Malmstrom’s group discovered that the old RNA in these descendents of common grain viruses had been protected by the viruses’ exterior proteins – and could still be recovered almost a century later.
“These are the oldest plant viruses anyone has gotten out of plant material in North America,” Malmstrom said.
The work suggests that these barley and cereal yellow dwarf viruses may have helped invasive grasses take over California in the 18th and 19th centuries.
The history, Malmstrom said, is important in understanding how viruses spread and change. People have been bringing in new species of plants to the New World since Columbus arrived in the 15th century, and these invasions rock the ecological world. In California, native perennial grasses gave way to new annual grasses, which make aphid populations larger. Because aphids can carry viruses over long distances, increases in their numbers can alter disease dynamics over a large area. In California more native grasses likely got sick after Europeans arrived, just as Native Americans did.
“We are able to take modern and historical viruses and put them in a family tree so we can start investigating how far back different virus groups split from each other,” Malmstrom said. “Our work suggests that some of the big branching of viruses happened during early global exploration by humans. We want to understand how human influence shapes how viruses evolve.”
Understanding what impact humans have on natural systems is especially important as the human world has much of natural ecology reined in. Malmstrom described human influence in terms of a net – one in which natural systems are increasingly hemmed in by a grid of roads, urban areas and fences.
“At night, the view of North America from outer space reveals a grid of lights that shows how we have built a net over the landscape – one that doesn’t let large controlling agents – be they stampedes of buffalos or fires – move across the landscape like they used to; they get caught in our net,” she said. “But those little aphids can still move through those nets and the viruses with them. The importance of viruses and small pathogens is going to be increasingly dominant as other forces have been controlled.”
The work was funded by the National Science Foundation and also supported by the Michigan Agricultural Experiment Station.
Michigan State University has been advancing knowledge and transforming lives through innovative teaching, research and outreach for more than 150 years. MSU is known internationally as a major public university with global reach and extraordinary impact. Its 17 degree-granting colleges attract scholars worldwide who are interested in combining education with practical problem solving.
Carolyn Malmstrom | EurekAlert!
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
23.07.2018 | Materials Sciences
23.07.2018 | Information Technology
23.07.2018 | Health and Medicine | <urn:uuid:a24d7e00-2485-4763-bcd4-35ef74389616> | 3.796875 | 1,560 | Content Listing | Science & Tech. | 35.494621 | 95,593,879 |
Using 3D electron microscopy, structural biologists from the University of Zurich succeeded in elucidating the architecture of the lamina of the cell nucleus at molecular resolution for the first time. This scaffold stabilizes the cell nucleus in higher eukaryotes and is involved in organizing, activating and duplicating the genetic material. Diseases such as muscular dystrophy and premature aging, caused by mutations in the lamin gene, the major constituent of the lamina, can now be studied more effectively.
Compared to bacteria, in eukaryotes the genetic material is located in the cell nucleus. Its outer shell consists of the nuclear membrane with numerous nuclear pores. Molecules are transported into or out of the cell nucleus via these pores.
Beneath the membrane lies the nuclear lamina, a threadlike meshwork merely a few millionths of a millimeter thick. This stabilizes the cell nucleus and protects the DNA underneath from external influences. Moreover, the lamina plays a key role in essential processes in the cell nucleus – such as the organization of the chromosomes, gene activity and the duplication of genetic material before cell division.
Detailed 3D image of the nuclear lamina in its native environment
Now, for the first time, a team of researchers headed by cell biology professor Ohad Medalia from the Department of Biochemistry at UZH has succeeded in elucidating the molecular architecture of the nuclear lamina in mammalian cells in detail. The scientists studied fibroblast cells of mice using cryo-electron tomography.
“This technique combines electron microscopy and tomography, and enables cell structures to be displayed in 3D in a quasi-natural state,” explains Yagmur Turgay, the first author of the study. The cells are shock-frozen in liquid ethane at minus 190 degrees without being pretreated with harmful chemicals, thereby preserving the cell structures in their original state.
“The lamin meshwork is a layer that’s around 14 nanometers thick, located directly beneath the pore complexes of the nuclear membrane and consists of regions that are packed more or less densely,” says Yagmur Turgay, describing the architecture of the nucleoskeleton.
The scaffold is made of thin, threadlike structures that differ in length – the lamin filaments. Only 3.5 nanometers thick, the lamin filaments are much thinner and more delicate than the structures forming the cytoskeleton outside the cell nucleus in higher organisms.
New approach for research on progeria and muscular dystrophy
The building blocks of the filaments are two proteins – type A and B lamin proteins – which assemble into polymers. They consist of a long stem and a globular domain, much like a pin with a head. Individual mutations in the lamin gene elicit severe diseases with symptoms such as premature aging (progeria), muscle wasting (muscular dystrophy), lipodystrophy and damage of the nervous system (neuropathies).
“Cryo-electron tomography will enable us to study the structural differences in the nuclear lamina in healthy people and in patients with mutations in the lamin gene in detail in the future,” concludes Ohad Medalia. According to the structural biologist, this method permits the development of new disease models at molecular level, which paves the way for new therapeutic interventions.
Yagmur Turgay, Matthias Eibauer, Anne E. Goldman, Takeshi Shimi, Maayan Khayat, Kfir Ben-Harush, Anna Dubrovsky-Gaupp, K. Tanuj Sapra, Robert D. Goldman, Ohad Medalia. The molecular architecture of lamins in somatic cells. Nature. March 1, 2017. DOI:10.1038/nature21382
Prof. Dr. Ohad Medalia
Department of Biochemistry
University of Zurich
Phone: +41 44 635 55 22
Dr. Yagmur Turgay
Department of Biochemistry
University of Zurich
Phone: +41 44 635 55 06
Kurt Bodenmüller | Universität Zürich
O2 stable hydrogenases for applications
23.07.2018 | Max-Planck-Institut für Chemische Energiekonversion
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
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03.07.2018 | Event News
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By: NP Singh and Vijay Sihag
Spiders are ubiquitous in natural and agricultural habitats. They are useful indicators of overall species richness and the health of terrestrial communities. This book contains information on 39 species belonging to 29 genera and 15 families.
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Scientist Discover Massive New Forests
Author: Laura Chalk
A new global analysis has discovered 467 million hectares of previously unreported forests. This amounts to an area equivalent to 60% of the size of Australia.
This new identification means the known amount of global forest cover has risen by 9% and will bolster estimates of how much carbon is stored in trees worldwide.
The research was headed by The Food and Agriculture Organisation of the United Nations and scientists from the University of Adelaide.
The new forests were found in previously-thought barren drylands – areas where plants receive far less water in precipitation than they lose. These arid areas contain 45% more forest than has been found in earlier surveys.
The forests were found in sub-Saharan Africa, the Mediterranean, India, Australia, western South America, Brazil, Colombia and Venezuela, and northern parts of Canada and Russia. Impressively, the amount of known dryland forest in Africa has doubled!
How The Forests Were Found
Advancements in satellite imaging technology and mapping techniques mean detection of these are now far easier. Dryland forests were previously difficult to measure globally because of the low density of trees and lower resolution satellite imagery.
Andrew Lowe from the University of Adelaide explains: “In the modern digital age, we think we know everything about the earth, but a lot of that knowledge comes from satellite imagery, like google earth. But when you use that type of satellite data, you have to make estimations on what type of vegetation occurs on the ground.” And many of those estimations have been proven wrong by the new tool.
The recent findings bring potentially far-reaching benefits. The arid lands analysed have more capacity to support trees than previously realized, which is significant as they make up about 40% of the Earth’s land surface. Some climate models suggest these dryland ecosystems could continue to expand by 11 – 23% by the end of this century – meaning they could cover more than half of Earth’s land surface.
Here lies a unique chance to combat climate change. Given the potential of these woodlands to mitigate desertification and combat climate change by storing carbon, it will be vital to continue monitoring the health of these forests, now their existence is known and technology can aid the effort.
This discovery can lead to improving the accuracy of models used to calculate how much carbon is stored in the earth’s natural environments. This means being able to better calculate carbon budgets and enabling countries to measure their progress towards targets.
Drylands contain some of the most threatened, yet disregarded, ecosystems. Climate change will cause many of these regions to become hotter and even drier, while human expansion could degrade these landscapes yet further. The hope is that the enthusiasm surrounding this comprehensive discovery leads to determination to protect, promote and conserve these unlikely new additions in the fight against climate change.
- Be a part forest expansion by planting your own tree on National Tree Day, July 30, 2017, or Schools Tree Day, July 28.
- Join a local bush regeneration or conservation group to preserve the natural environment in your area:
- Ensure your wood products are FSC certified (if in Australia, or equivalent in your country), to ensure protection of forests.
Subscribe to Positive Environment News.
Positive Environment News has been compiled using publicly available information. Planet Ark does not take responsibility for the accuracy of the original information and encourages readers to check the references before using this information for their own purposes.
Laura joined Planet Ark in 2016. She has a wealth of knowledge and experience having travelled the world and a background in teaching English as a second language among other things.
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Elise with some tips on reducing kitchen waste as part of her Plastic Free July journey.... More » | <urn:uuid:b0255e2c-e605-4224-92f9-d5865ca4b4f5> | 3.53125 | 975 | Content Listing | Science & Tech. | 35.250231 | 95,593,929 |
Feb 23, 2018
Feb 09, 2018see all
Putting sequences into a chromosome context
The original model for representing the genome assemblies was to use a single, preferred tiling path to produce a single consensus representation of the genome. Subsequent analysis has shown that for most mammalian genomes a single tiling path is insufficient to represent a genome in regions with complex allelic diversity. The GRC is now working to create assemblies that better represent this diversity and provide more robust substrates for genome analysis.
GRCg6a (GCA_000002315.5), the latest chicken reference genome assembly is released.
Slides from the GRC workshop at ASHG 2017 are now on SlideShare
Transitioning to GRCh38 or GRCz11? Try the NCBI Remapping Service, which uses the same assembly-assembly alignments used by the GRC.
Subscribe to the grc-announce email list to receive email notification for all GRC assembly updates. | <urn:uuid:ef22cf8b-a63a-44bf-bbe0-4feda521038f> | 2.8125 | 202 | News (Org.) | Science & Tech. | 34.64 | 95,593,931 |
Natural time periods between celestial phenomena hold powerful insights into the numerical structure of time, insights which enabled the megalith builders to access an explanation of the world unlike our own. When looking at two similarly-long time-periods, the megalithic focussed on the difference between them, this causing the two periods to slide in and out of phase, generating a longer period in which the two celestial bodies exhibit a complete ensemble of variation, in their relationship to each other. This slippage of phase between celestial periods holds a pattern purely based upon number, hidden from the casual observer who does not study them in this way. Such numerical patterns are only fully revealed through counting time and analysing the difference between periods numerically.
For example, the solar year is longer than the lunar year by 10 and 7/8 days (10.875 days) and three solar years are longer than three lunar years by three times 10.875 days, that is by 32 and 5/8th days (32.625 days), which is 32/29 of a single lunar month of 29.53 days.
Figure 1 (in plan above) The monumentalising of a three-year day inch count at Le Manio as a right triangle based upon its southern kerb (in profile below), automatically generating the megalithic yard.
The earliest and only explicit evidence for such a three-year count has been found at Le Manio’s Quadrilateral near Carnac (circa 4,000 BCE in Brittany, France), which employed the inches we still use to count days, a “day-inch” unit then widespread throughout later megalithic monuments and still our inch, 1/12 of the foot [Heath & Heath. 2011]. The solar-lunar difference found there over three years was 32.625 day-inches, this length the probable origin of the unit we call the megalithic yard, coined by Alexander Thom. The megalith builders seem to have adopted this differential length, between a day-inch count over three lunar and solar years, as a measure for building many later monuments.
Le Manio’s Quadrilateral (figure 1) shows that the geometry of the right triangle was employed to express and manipulate lengths of time as day-inch counts of lunar and solar years. In such a triangle, the difference is revealed between its two longer sides, a difference most clearly seen between the right angle of the triangle (at stone 36 on its base) and the end of the longest side “arced down” over the base (stone 37) using ropes. This longest side, symbolically aligned to the summer solstice sunrise, contains no stones: implying that the solar count was used to inform the subsequent construction of the triangle between lunar and solar lengths, only then to build the southern kerb of stones whose exact positions and shapes, we shall see, then corresponding to other time periods within three years that were deemed significant (see figure 2).
Figure 2 The southern kerb of the Quadrilateral in silhouette, looking south,
based on a calibrated photo montage. Note that western edge of stone 35 is located where
three eclipse years would end when counted from stone 1.
If one makes the differential length into a megalithic yardstick, one can count the number of those yards in the base and longest sides of the triangle as being 32.625 and 33.625, that is as being just one megalithic yard different. This is a powerful feature of right triangles, that their differential length always divides into its longest sides to “normalise” the triangle, as being an N:N+1 triangle. It is also true that whatever the number of years over which lunar and solar years are counted, the triangle will be self-similar (of the same form), having side ratios of 32.625:33.625. By good fortune, the megalithic noticed the short near-anniversary over three years of 36 and 37 lunar months, so giving them the invariant N = 32.625, as the difference – which it need not have been! This led me to the conclusion, in my books, that such good fortune facilitated the arising of megalithic astronomy at a time when Neolithic activities were thought only to have been evolving early forms of agriculture, rather than an advanced astronomy based upon counting time.
Le Manio therefore represents the foundational application of time counting, of the two main luminaries, by studying numeric differences to systematise time. Within the three year frame of synodic time lie other interesting phenomena including the lowest number of lunar months that occurs on an integer number of solar days: In 32 lunar months there are exactly 945 days, to within half an hour. This allowed an accurate approximation to the actual length of the lunar month if 945 days are divided into 32 parts, each one therefore being 29.53125 day-inches long. This compares to the true average lunar month of 29.53059 days, to one part in 44743 and so is therefore, effectively exact. But to access such an estimate as a length, there had to be a megalithic technology capable of dividing 945 by 32.
There is evidence in the late stone age for the study of how numbers interacted, using objects like beads and etched patterns on bones and rock surfaces. It is quite possible to factorise a long count by using a measuring rod to count: if there is no partial excess then the length of the measuring rod (in inches) is a factor of the number in day-inches. The factors of 945 day-inches are 33 x 5 x 7. A cube 27 by 5 by 7 inches would contain 945 cubic inches. A technique was then developed which I call “proximation”, where two similar numbers with suitable factors can be placed within a right triangle – enabling the geometrical equivalent of division, given suitable factors within the two numbers.
Those factorising in this way would know 32 as the product of five twos (25) and would also see within 945 the factors 9 x 7 as those making up 63, just one less than the twice the 32 lunar months, and the 64 is the product of six twos (26 = 64). Divided into 63 parts, each part of 945 day-inches would be 15 day-inches long, whilst 64 x 15 = 960, the longest side over the base of 945 in a right triangle.
Figure 3 Exploiting the factors of 945 day-inches to rescale and resolve an accurate length for the lunar month
However, by using 64 one has doubled 32, and we are looking for a proximate length to 30 day-inches rather than the natural factor 15 day-inches. Therefore, they looked at the “sharp” end of the triangle (see figure 3) and saw above (on the hypotenuse) two 15-day periods equalling 30 days. The base of the triangle (shown in yellow) is then automatically 64/63 x 30 day-inches, which equals 29.53125 day-inches, the lunar month. That is a 63:64 triangle was possible with hypotenuse equal to 30 day-inches and base 29.53125 day-inches, but this size was a bit too small for convenience.
The fractional part of 29.53125 day-inches is 17/32 day-inches but measuring to 32nds of an inch was not practical so instead; they quadrupled the counting units by generating the length of four lunar months, i.e. a hypotenuse length of 120 day-inches or ten feet (now called a double-fathom or perch). This rendered the size of the fractional part of the base length, using a four-times bigger triangle, 17/8th or 2 plus 1/8th. This length, of 118.125 inches long is the number of day-inches in four lunar months to high accuracy and this would have been a familiar counting length for megalithic astronomer in this earliest phase, since two months are about 59 day-inches long, cancelling the half day in 29.53 day-inches. Doubling again to 118 1/8th day-inches (118.125) resolves the more practical factional measure of 1/8th day-inch (0.125).
We can see the 32 lunar month period in the end of the 31st stone of the southern kerb at Le Manio. From the left-hand edge of stone 31, to the gap between the solstice “Sun Gate”, measures 945 inches. Then there is a gap filled by stone 32 which is narrow. Why make stone 32 narrow with gaps? Firstly, one should point out it could have been laid later, in imitation of stone 35.
Figure 4 Calibrated photo survey conducted of Le Manio’s Southern Kerb in 2010.
I believe stone 32 sits in a gap representing the 0.625 of a lunation between 32 and 32.625 lunar months. The reader may remember that 32.625 is N for the normalised N: N+1 relationship of the triangle formed between three lunar years and three solar year. Over three lunar and solar years, this manifest as a single whole lunar month (in angle) of the sun on the ecliptic, when the sun is illuminating the 32nd lunar month. That is, the sun is moving whilst the moon is being illuminated by it. The 33rd stone of the southern kerb therefore represents the whole lunar month between 32.625 and 33.625 months in the day-inch count, whilst the 32nd stone, with unusual gaps either side, is narrow (from starting at 32 months in the count) to represent 0.625 of a lunar month.
That is, the 33rd stone was intended to be the lunar month.
Also in the frame of Figure 4 is stone 29 and above we stated:
the solar year is longer than the lunar year by 10 and 7/8 days (10.875 days) and three solar years are longer than three lunar years by three times this, 32 and 5/8th days (32.625 days), which is 32/29 of a single lunar month of 29.53 days.
The gap between stones 32 and 29 relative to the “sun gate” represents the normalising difference which resolves, somewhat miraculously, to the numbers 32 and 29 in relating the astronomical megalithic yard (32 units of 1.0183 inches) to the lunar month (29 of 1.0183 inches); in a day-inch count over three years.
In part two I will look at the overall form of the monument as an integrated expression of synodic spacetime.
Summary and Conclusions
In counting order therefore, the end of the southern kerb (if we read it numerically) at least portrays within its choice and disposition of stones,
- the difference between the lunar month and the three-year differential equal to the megalithic yard in day-inch counting.
- the 32 lunar month equivalence to 945 days which gives a highly accurate estimate of the lunar month of 118 and 1/8th day-inches divided by four (29.53125).
- the gap of 0.618 months between 32 and 32.625, N for the solar-lunar ratio over three years.
- Three eclipse years from the start to the westernmost edge of stone 35 (1040 day-inches).
- Three lunar years from the start to stone 36 (1063 day-inches), numerically 3 x 12 lunar months.
- Three solar years from the start to the end of stone 37 (1096 day-inches).
The stones of the Quadrilateral appear to have been laid to form a numeric sketch pad of key relationships visible within its range of three solar years of day-inch counting. | <urn:uuid:1a06888e-e2c0-4891-ac72-a29c37adfbf5> | 3.84375 | 2,472 | Academic Writing | Science & Tech. | 63.574353 | 95,593,937 |
Species Detail - Giant Puffball (Calvatia gigantea) - Species information displayed is based on all datasets.
Terrestrial Map - 10kmDistribution of the number of records recorded within each 10km grid square (ITM).
Marine Map - 50kmDistribution of the number of records recorded within each 50km grid square (WGS84).
Bovista gigantea, Langermannia gigantea, Lasiosphaera gigantea, Lycoperdon giganteum
12 August (recorded in 1987)
23 September (recorded in 2016)
National Biodiversity Data Centre, Ireland, Giant Puffball (Calvatia gigantea), accessed 19 July 2018, <https://maps.biodiversityireland.ie/Species/157228> | <urn:uuid:faa6d7e9-d23e-423c-8e46-a46ccbaacb35> | 2.640625 | 171 | Structured Data | Science & Tech. | 25.369778 | 95,593,942 |
Coming decades vital for future sea level rise: study
By Marlowe HOOD
How quickly humanity draws down the greenhouse gases driving global warming will determine whether sea levels rise half-a-metre or six times that, even if Paris climate pact goals are fully met, researchers reported Tuesday in a study.
“The trajectory of emissions in the next few decades will shape our coastlines in the centuries to come,” lead author Matthias Mengel, a scientist at the Potsdam Institute for Climate Impact Research in Germany, told AFP.
Every five years that elapse before carbon pollution peaks will add 20 centimetres to sea level rise in 2300, the study found.
“This is the same amount we have experienced so far since the beginning of the fossil fuel economy,” Mengel said by email.
The world collectively spews about 40 billion tonnes of CO2 into the atmosphere every year. After stalling for three years, emissions rose by two percent in 2017, dashing hopes they had peaked.
On current trends, emissions could increase for at least another decade.
The 197-nation Paris Agreement calls for capping global warming at “well below” two degrees Celsius (3.6 degrees Fahrenheit), and pursuing efforts to hold the line at 1.5 C.
Average global temperatures have already gone up by 1 C since the industrial revolution began.
The treaty also sets a less talked about but equally crucial goal: ensuring that, by the end of this century, our species stops adding CO2 to the atmosphere, a threshold known as “net zero emissions”.
Mengel and colleagues asked a deceptively simple question: by how much will the world’s oceans rise over the next two centuries if both these targets are achieved?
The most likely outcome, they found, was an increase of 70 to 120 centimetres (27.5 to 47 inches) by 2300, depending on when CO2 pollution peaks, how quickly it drops, and the date net zero emissions is achieved.
That’s probably enough to doom some low-lying island states and wreak havoc in the populated mega-deltas of Bangladesh, Vietnam, India and Egypt, but would at least leave more time to adapt.
– Redrawing coastlines –
Currently, some 100 million people live within a metre (three feet) of the high-tide level, leaving them vulnerable not only to sea level rise but evermore powerful storm surges.
The study also showed, however, that fulfilling the Paris mandate does not necessarily avert catastrophic change.
If carbon emissions don’t peak until 2035 and CO2 continues to leech into the atmosphere until 2090, for example, the ocean watermark could go up three metres by 2300, rendering continental coastlines unrecognisable.
And if the Paris temperature goal is not met, there is a small chance oceans would rise five metres.
The biggest wild card in predicting future sea levels is the Antarctic ice sheet, which contains enough frozen water to lift oceans several dozen metres.
Its western peninsula is especially sensitive to climate change.
“Large ice loss seems possible even under modest warming in line with the Paris agreement,” said Mengel. “A sea level rise of up to three meters by 2300 cannot be ruled out.”
Ocean uplift is also driven by the expansion of water as it warms, and runoff from melting glaciers.
Earth’s atmosphere responds far more quickly to cuts in greenhouse gas emissions than oceans. Indeed, scientists estimate that there is at least half-a-metre of “committed” sea level rise already in the pipeline, perhaps more.
“Even if we stop emitting today, the effects of our past emissions will be felt for centuries to come,” said Pete Strutton, an oceanographer at the University of Tasmania.
“Every year that we delay action has consequences for the future.”
Matthias Mengel acknowledged that the best-case projections in the study are “really optimistic”.
Despite voluntary, carbon-cutting pledges by virtually all the world’s nations, global temperatures are on track to rise 3 C above pre-industrial levels by 2100.
“In the end, the Paris Agreement will not be evaluated on what it promised or aspires to do, but on the change it managed to catalyse and the emissions reductions achieved in the real world,” said co-author Joeri Rogelj, a climate modeller at the International Institute for Applied Systems Analysis in Austria. | <urn:uuid:f9c9bd15-3c61-4fb2-85b5-8f9b571c08b4> | 3.5 | 953 | Truncated | Science & Tech. | 40.241138 | 95,593,959 |
Rising carbon dioxide levels in the ocean have been shown to adversely affect shell-forming creatures and corals, and now a new study by researchers at Scripps Institution of Oceanography at UC San Diego has shown for the first time that CO2 can impact a fundamental bodily structure in fish.
A brief paper published in the June 26 issue of the journal Science describes experiments in which fish that were exposed to high levels of carbon dioxide experienced abnormally large growth in their otoliths, or ear bones. Otoliths serve a vital function in fish by helping them sense orientation and acceleration.
The researchers had hypothesized that otoliths in young white seabass growing in waters with elevated carbon dioxide would grow more slowly than a comparable group growing in seawater with normal CO2 levels. They were surprised to discover the reverse, finding “significantly larger” otoliths in fish developing in high-CO2 water.
The fish in high-CO2 water were not larger in overall size, only the otoliths grew demonstrably bigger.
“At this point one doesn’t know what the effects are in terms of anything damaging to the behavior or the survival of the fish with larger otoliths,” said David Checkley, a Scripps Oceanography professor and lead author of the new study. “The assumption is that anything that departs significantly from normality is an abnormality and abnormalities at least have the potential for having deleterious effects.”
With carbon dioxide levels rising due to human activities, particularly fossil fuel burning, resulting in both increased ocean CO2 and ocean acidification, the researchers intend to broaden their studies to examine specific areas, such as determining whether the otolith growth abnormality exists in fish other than white seabass; locating the physical mechanism that causes the enhanced otolith growth; and assessing whether the larger otoliths have a functional effect on the survival and the behavior of the fish.
“Number three is the big one,” said Checkley. “If fish can do just fine or better with larger otoliths then there’s no great concern. But fish have evolved to have their bodies the way they are. The assumption is that if you tweak them in a certain way it’s going to change the dynamics of how the otolith helps the fish stay upright, navigate and survive.”
In addition to serving in orientation and acceleration, otoliths help reveal physical characteristics of fish. Because otoliths grow in onion-like layers, scientists use otoliths to determine the age of fish, counting the increments similar to tree-ring dating.
Coauthors of the paper include Andrew Dickson, John Radich and Rebecca Asch of Scripps Oceanography; Motomitsu Takahashi of the Seikai National Fisheries Research Institute in Nagasaki, Japan; and Nadine Eisenkolb of the University of Southern California.
The research was supported by the Academic Senate of UC San Diego.
Scripps News: scrippsnews.ucsd.edu
Scripps Institution of Oceanography, at UC San Diego, is one of the oldest, largest and most important centers for global science research and education in the world. The National Research Council has ranked Scripps first in faculty quality among oceanography programs nationwide. Now in its second century of discovery, the scientific scope of the institution has grown to include biological, physical, chemical, geological, geophysical and atmospheric studies of the earth as a system. Hundreds of research programs covering a wide range of scientific areas are under way today in 65 countries. The institution has a staff of about 1,300, and annual expenditures of approximately $155 million from federal, state and private sources. Scripps operates one of the largest U.S. academic fleets with four oceanographic research ships and one research platform for worldwide exploration.
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
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Several years ago, when memory sizes were measured in Kilobytes and hard drive capacity in Megabytes, I came up with this trick for knowing the powers of two.
As an aside, my first personal computer (an Apple ][, acquired in 1979) came with 4K bytes of memory and no disk drive at all (a cassette tape interface was all there was for storage). I spent a couple of hundred dollars to upgrade the memory to 16K bytes. My first IBM-compatible PC (1988) had 256K (bytes) of memory and a 20Mbyte hard drive. How times have changed!
The (Intel) processor in an IBM PC could only use 16 bits to form a memory address. It turns out that this is enough capacity for there to be a unique address for each of 64 Kilobytes (about 64 thousand bytes).
Each bit can have only one of two possible values, typically written as zero or one. Here is a little table showing how many different bit combinations there are for different numbers of bits:
1 bit gives you two possible values (0 and 1)
2 bits give you four possible values (00, 01, 11 and 10)
3 bits give you eight possible values (000, 001, 011, 010, 110, 111, 101 and 100)
and so on
In each case, I have been able to show all of the possible bit patterns. But the number of possible bit patterns doubles each time we add on an additional bit. The numbers get big quite quickly, and it would soon become very tedious to write out all of the possible bit patterns.
Mathematicians would express this relationship--number of bits and the number of possible bit patterns--using powers of two. The sidebar shows a chart from 0 bits through 9 bits.
You'll recognize three of these lines from the earlier table (showing 2, 4 and 8 possible values, for 1, 2 and 3 bits, respectively).
Above those lines, there is a bit of an oddity for zero bits, allowing only one pattern.
Now, if you want to learn my little memory trick, you will have to memorize these ten lines. This effort will be well repaid, as this will allow you to mentally state memory or disk sizes from the smallest to the largest in use today.
Where things get interesting is at 10 bits, which allow us to produce 1024 possible bit patterns.
What is interesting about this is that 1024 is the number commonly known as "Kilo". And, this is really quite close to one thousand.
Now, the power of 2, as represented by the exponent--the number shown attached to the upper right hand corner of the 2--can be interpreted as the number of bits that we have available for producing possible bit patterns. The other number--after the equals sign--is the number of possible bit patterns.
If you've studied powers and exponents, you'll know that you can add exponents (on the left) by multiplying numbers on the right of the equal sign. So, for example 2 to the 16 will be equal to 1024 (2 to the power 10) times 64 (2 to the power 6). This yields the number 65536, but which is more commonly expressed as 64K.
This is just another way of saying that 16 bits allow us to have a distinct address (bit pattern) for each of 64 Kilobytes. This is approximately 64 thousand bit patterns, because 2 to the power 10 is approximately one thousand. Similar approximations hold for 2 raised to 20, 30, 40, etc.
As it happens, 10 bits allow us about a thousand possible bit patterns, 20 bits allow about a million possible bit patterns, 30 bits allow about a billion possible bit patterns, and so on.
Now we are ready for the trick. When you have some number of bits (between none and 69), you can combine what you know from these two figures.
Let's try a few examples. If you have 24 bits, that would be about 16 million possible bit patterns. The "16" comes from the first figure, where 2 raised to 4 gives us 16. The "million" comes from the second table where 2 raised to 20 gives us about a million. Of course, 24 is just 4+20, so the law of exponents will be satisfied. This is also written "16M" or "16 megs" or "16 megabytes".
If you have 32 bits, that would be about 4 billion possible bit patterns. This is also written 4G, or "4 gigs" or "4 gigabytes".
Now, what if you have 64 bits? Would that be twice as many possible bit patterns as 32 bits? No, 64 bits would be about 16 thousand quadrillion possible bit patterns.
It works the other way, too. How many bits would you need for twice as many bit patterns as you get from 32 bits? Well, 32 bits gives us about 4 billion patterns, so we need about 8 billion bit patterns. Using the two figures, we can see that it will take 33 bits to give us about 8 billion bit patterns.
Did anyone actually get this far? Hope you find this useful.
Harriet Jarman Layton's song
2 hours ago | <urn:uuid:ff32f391-2dd3-4051-8a16-68c1ee876ef6> | 3.578125 | 1,083 | Personal Blog | Science & Tech. | 69.724442 | 95,593,994 |
Go gotcha: newbie or ninja?
27 sneaky traps and corner cases
This collection of gotchas and pitfalls in Go is intended to help you find and fix similar problems in your own code.
Some of the puzzles are pretty easy. To solve all 27, you have to be a ninja.
Table of contents
Assignment to entry in nil map
You have to initialize the map before you can add any elements.
Nil pointer dereference
An uninitialized pointer is nil, and you can't follow the nil pointer.
Multiple-value in single-value context
When a function returns multiple values, you must take care of each one. You can use the blank identifier (underscore) to ignore unwanted return values.
Array won’t change
Arrays in Go are values: when you pass an array to a function it gets a copy of the original array data.
An identifier declared in a block may be redeclared in an inner block.
In a multi-line slice, array or map literal, every line must end with a comma.
String won’t change
Go strings are read-only byte slices (with a few extra properties).
Adding one character at a time
Characters (rune literals) are integer values used to identify Unicode code points.
What happened to ABBA?
The Trim functions strip all Unicode code points contained in a cutset.
Where is my copy?
Copy copies the minimum number of elements in the destination and source slices.
Why doesn’t append work every time?
If there is enough capacity, append reuses the underlying array.
Constant overflows int
An untyped integer constant is converted to an int when the type can't be inferred from the context.
In Go increment and decrement are statements written with postfix notation.
Does not compute
The multiplication, division, and remainder operators have the same precedence.
Go and Pythagoras
The circumflex (^) denotes bitwise XOR in Go.
No end in sight
An integer overflow occurs when an arithmetic operation tries to create a value that is outside the range that can be represented.
Numbers that start with zero
Octal literals start with 0, hexadecimal with 0x, an decimal literals never start with zero.
The remainder operator can give negative answers if the dividend is negative.
Time is not a number
There is no mixing of numeric types in Go.
Index out of range
Arrays, slices and strings are indexed starting from zero.
Unexpected values in range loop
The range loop generates two values: first the index, then the data.
Can’t change entries in range loop
The range loop uses a local variable to store iteration values.
Iteration variable doesn’t see change in range loop
The range expression is evaluated once before beginning the loop.
Iteration variables and closures
A data race occurs when two goroutines access the same variable concurrently and at least one of the accesses is a write.
No JSON in sight
Only the the exported fields of a Go struct will be present in the JSON output.
Is "three" a digit?
Most of the functions in the regexp package do substring matching.
Nil is not nil
An interface value is nil only if the concrete value and dynamic type are both nil.
The Concurrent programming tutorial covers the fundamentals of concurrent programming with examples in Go.
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More than thirteen years have passed, since Jean-Claude Nourissat and Patrick de Rham began their quest (January 1991) for the elusive cichlids of Madagascar. This book is an update of all the knowledge that they have accumulated during their forays in the Grande Ile, in which the diversity of cichlids was found to be much higher than previously believed. At the beginning of their investigations, only nine valid species of endemic cichlids were scientifically described. Today they number 19, more new descriptions are underway and close to 50 species and geographical populations have been recorded.
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Viscometer for use at High Temperatures and Pressures
The study of liquids at high temperatures and pressures necessitates the use of gas as the pressurizing medium. A sealed collapsible Container, or a rigid Container with flexible bellows is often used to isolate the fluid from the pressurizing gas. These conditions make it very difficult to measure viscosity. Even more difficult is the study of fluids containing dissolved volatiles such as, in our case, water rich magmas. These fluids must be sealed in a Container to keep the water in and the pressurizing gas out. Our viscometer allows one to measure the viscosity of a fluid within a sealed Container, and is based on the work of Robinson and Smedley . The device is a development of the torsionally oscillating quartz crystal technique used previously at low temperatures and high pressures [2,3].
KeywordsShear Rate Complex Viscosity Piezoelectric Crystal Drive Voltage Torsional Wave
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For years, astronomers have been developing a picture of galaxy evolution in which mergers between spiral galaxies could explain why nearby large elliptical galaxies have so few young stars. The theoretical picture is chaotic and violent: The merging galaxies knock gas and dust into clumps of rapid star formation, called starbursts, and down into the maws of the supermassive black hole growing in the merger's core. As more and more matter heaves onto the black hole, powerful jets erupt, and the region around the black hole glows brilliantly as a quasar. The jets blowing out of the merger eventually plow out the galaxy's potential star-forming gas, ending the starbursts.
An artist's concept of an active supermassive black hole and its jet, with outflow of star-forming gases. Credit: Wolfgang Steffen, Cosmovision; Marscher et al., NRAO/AUI/NSF
Until now, astronomers had never spotted enough mergers at this critical, jet-plowing stage to definitively link jet-driven outflows to the cessation of starburst activity. During its Early Science observations in late 2011, however, ALMA became the first telescope to confirm nearly two dozen galaxies in this brief stage of galaxy evolution.
What did ALMA actually see? "Despite ALMA's great sensitiviy to detecting starbursts, we saw nothing, or next to nothing - which is exactly what we hoped it would see," said lead investigator Dr. Carol Lonsdale of the North American ALMA Science Center at the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia. Lonsdale presented the findings at the American Astronomical Society's meeting in Austin, Texas on behalf of an international team of astronomers.
For these observations, ALMA was tuned to look for dust warmed by active star-forming regions. However, half of Lonsdale's two dozen galaxies didn't show up at all in ALMA's observations, and the other half were extremely dim, indicating that there was very little of the tell-tale dust present.
"ALMA's results reveal to us that there is little-to-no starbursting going on in these young, active galaxies. The galaxy evolution model says this is thanks to their central black holes whose jets are starving them of star-forming gas," Lonsdale said. "On its first run out of the gate, ALMA confirmed a critical phase in the timeline of galaxy evolution."
Once their star-forming gas has been blown away, merging galaxies will be unable to make new stars. As the last generation of massive and brilliant, but short-lived, blue stars dies out, the long-lived, lower mass, redder stars come to dominate the merger's star population, giving the gas-starved galaxy an overall reddish hue over time.
A New Method for Finding Candidate Starving Galaxies
To support this gas-starvation theory, astronomers needed to see it at work in lots of merging galaxies with high power jets. The place to observe enough of them is among the quasars, active galaxies found in the Universe's past, several billion light-years away.
Lonsdale said, "The missing phase had to be among quasars that could be seen brightly in infrared and radio wavelengths -- mergers young enough to have their cores still swaddled in infrared-bright dust, but old enough that their black holes were well fed and producing jets observable in the radio."
Their selective hunt for these specific quasars started with NASA's Wide-field Infrared Survey Explorer (WISE) spacecraft, which has hundreds of millions of objects in its all-sky, infrared survey of the Universe. Lonsdale led WISE's quasar survey team that picked out the brightest, reddest objects this infrared telescope had mapped.
The team then compared its selections with NRAO's VLA Sky Survey of 1.8 million radio objects and chose the overlapping results as the most suitable targets for their search for starburst activities with ALMA. Observing at longer infrared wavelengths than WISE, ALMA enabled Lonsdale's team to discriminate between dust warmed by starburst activity and dust heated by material falling onto the central black hole.
ALMA has 26 more WISE quasars to probe before Lonsdale and her international team publish their results later this year. Meanwhile, she and her team will observe these galaxies, and over a hundred more, with NRAO's newly upgraded Karl G. Jansky Very Large Array (VLA).
"ALMA revealed to us this rare stage of galaxy starvation, and now we want to use the VLA to focus on delineating the outflows that robbed these galaxies of their fuel," Lonsdale said. "Together, the two most sensitive radio telescope arrays in the world will help us truly understand the fate of spiral galaxies like our own Milky Way."
The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan. ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.
Tania Burchell | EurekAlert!
What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin
Subaru Telescope helps pinpoint origin of ultra-high energy neutrino
16.07.2018 | National Institutes of Natural Sciences
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Life Sciences
18.07.2018 | Materials Sciences
18.07.2018 | Health and Medicine | <urn:uuid:b80a7c96-e095-4f48-a14f-37ee180e2bf6> | 3.90625 | 1,899 | Content Listing | Science & Tech. | 38.2963 | 95,594,057 |
Astronomy research from the STEM School of Physical Sciences (SPS) among Physics World 2016 top breakthroughs.
As part of an international team of astronomers, Postdoctoral Researcher Dr John Barnes of SPS was instrumental in establishing that the observed ‘wobble’ of Proxima Centauri was caused by a nearby planet, which is referred to as Proxima b.
He said: “Once we had established that the wobble wasn’t caused by star spots, we knew that that there must be a planet orbiting within a zone where water could exist, which is really exciting. If further research concludes that the conditions of its atmosphere are suitable to support life, this is arguably one of the most important scientific discoveries we will ever make.”
For more information about this amazing discovery visit the article on the Science News website.
In addition to teaching on Open University modules our academics are engaged in ground breaking research that benefits individuals and society.
Explore our qualifications and courses by requesting one of our prospectuses today.Request prospectus | <urn:uuid:0f64b165-1837-47ab-ad38-79dc01d64218> | 2.65625 | 216 | News (Org.) | Science & Tech. | 28.412059 | 95,594,079 |
The Age of Euler
The eighteenth century was in mathematics a period of consolidation and exploitation of the great discoveries of the seventeenth century, and of their application to the investigation of scientific problems. The dominant figure of this period was Leonhard Euler, the most prolific mathematician of all time—his collected works amount to approximately seventy-five substantial volumes. The range and creativity of his fundamental contributions, to all branches of both pure and applied mathematics, would perhaps justify Euler’s inclusion in the traditional short list—Archimedes, Newton, Gauss—of the incomparable giants of mathematics.
KeywordsEighteenth Century Differential Calculus Interpolation Formula Integral Calculus Exponential Series
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- The Works of George Berkeley, vol. 4. London: Nelson, 1951.Google Scholar
- F. Cajori, Indivisibles and ‘ghosts of departed quantities’ in the history of mathematics. Scientia 37, 303–306, 1925.Google Scholar
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- H. W. Turabull, James Gregory: A study in the early history of interpolation. Froc Edinburgh Math Soc 3(2), 151–178, 1932–33.Google Scholar | <urn:uuid:7ac881c8-ee9d-405c-9e80-dece4154942f> | 3.171875 | 464 | Truncated | Science & Tech. | 53.329603 | 95,594,114 |
Quantum Mechanics of the Hydrogen Atom
In this chapter, we shall solve the Schrödinger equation of the hydrogen atom. For our calculations, we will not initially restrict ourselves to the Coulomb potential of the electron in the field of the nucleus of charge Z, V(r) = − Ze 2/(4πε0 r), but rather will use a general potential V(r), which is symmetric with respect to a centre. As the reader may know from the study of classical mechanics, the angular momentum of a particle in a spherically symmetric potential field is conserved; this fact is expressed, for example, in Kepler’s law of areas for the motion of the planets in the solar system. In other words, we know that in classical physics, the angular momentum of a motion in a central potential is a constant as a function of time. This tempts us to ask whether in quantum mechanics the angular momentum is simultaneously measurable with the energy. As a criterion for simultaneous measurability, we know that the angular momentum operators must commute with the Hamiltonian. As we have already noted, the components l x , l y , and l z of the angular momentum l are not simultaneously measurable; on the other hand, l z and l 2, for example, are simultaneously measurable. A long but straightforward calculation reveals that these two operators also commute with the Hamiltonian for a central-potential problem. Since the details of this calculation do not provide any new physical insights, we shall not repeat it here.
KeywordsHydrogen Atom Angular Momentum Quantum Mechanics Quantum Number Coulomb Potential
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- J. Avery: Quantum Theory of Atoms, Molecules, and Photons ( McGraw-Hill, New York 1972 )Google Scholar
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Konstanz biologists study the principles underlying the collective movement of baboons
How do baboons succeed in coordinating the movements of their group? Biologists at the University of Konstanz study these organisms in the wild to find out which behavioural rules baboons use when interacting with others.
Konstanz researchers have found out that the animals only need a few simple rules to coordinate their group movements, enabling them to organise themselves, and to make decisions, without splitting. In four recent research publications – published in the journals Science, Scientific Reports, eLife and the Proceedings of the Royal Society B – the Konstanz scientists paint a new picture of group dynamics among baboons with unprecedented detail by tracking how individuals make decisions within a group.
Research partners were the Max Planck Institute for Ornithology, the Smithsonian Tropical Research Institute in Panama as well as Princeton University, the University of California, Davis, and the University of Illinois at Chicago (all USA).
Baboons have long been studied because they have a highly complex social structure, forming groups from 20 to over 100 individuals. Such social structure suggested to early biologists that baboons must employ high levels of cognition to be able to coordinate their behaviour with so many group mates. For example, classical theories on group coordination among baboons suggested that the larger, grown-up individuals should stay at the periphery of the group to protect younger and weaker animals in the centre.
However, to constantly keep up this positioning, each baboon would need to know, at all times, where the other members of the group are. Konstanz biologists have now demonstrated that this is not necessarily the case – neither is there a need for it. "Actually, coordinating their movement with only a few neighbouring individuals can generally be enough for animals to keep their group together, and what we see in the baboons is consistent with this idea", explains biologist Dr. Ariana Strandburg-Peshkin.
Mathematics can further explain how individuals maintain specific positions within the group (either close to the center, at the front, back, or at the periphery) as her colleague Dr. Damien Farine explains: "If a baboon tries to stay together with only a slightly larger number of neighbouring individuals, this baboon will automatically move closer to the centre of the group. By contrast, individuals that coordinate their positions with a smaller number of fellow group members will end up at the group's periphery."
This means that the neighbourhood size, i.e. the number of members in the neighbourhood an animal stays together with, is decisive for maintaining the group structure. "This simple rule makes it possible to consistently describe the movements of the baboons.
Consequently, the group structure results from local behavioural principles of individual animals and not from a joint decision taken by the entire group", says Professor Iain Couzin (University of Konstanz and Max Planck Institute for Ornithology), adding: "We also observe that the movement rules of baboons, and how they make decisions, very much resembles the decision processes found in schools of fish and flocks of birds."
For their research the biologists studied a group of 25 baboons living in the wild in Kenya – a complex project headed by Professor Margaret Crofoot (University of California, Davis). A GPS transmitter provided locations of the individual animals, second-by-second, for two weeks. The scientists combined the movement data of the animals with remote images of the three-dimensional environment and vegetation structure recorded by a drone to obtain an overall picture of the surrounding conditions.
The evaluation of these data provides new insights into the collective behaviour of the baboons. In a series of publications, the researchers have also examined group dynamics and factors that influence the movements of individual animals of the group, and ultimately determine the entire group structure. The inclination to follow other group members is the strongest factor driving the decision-making behaviour of baboons. For example, baboons prefer paths that other group members have taken shortly before. The more baboons use a certain path, the more attractive it becomes for the others. In situations where they need to decide in which direction to move, if several members of the group head in different directions, baboons are inclined to follow the majority (i.e. the direction where most of their group mates are headed).
”Together, these studies capture new insights into how baboons make decisions. No longer do we believe that a single dominant male leads the troop, deciding on behalf of everyone”, says Damien Farine. Instead, University of Konstanz researchers have revealed that baboon life is much more democratic, and that many of the complex behaviours they exhibit might actually be the outcome of simple behavioural rules, potentially allowing individuals to spend more time thinking about other things – such as looking out for predators.
1) Strandburg-Peshkin, A.*, Farine, D.R.*, Couzin, I.D., Crofoot, M.C. (2015) Shared decision-making drives collective movement in wild baboons. Science 348(6241): 1358-1361. * joint first authors
2) Farine, D.R., Strandburg-Peshkin, A., Berger-Wolf, T., Ziebart, B., Brugere, I., Li, J., Crofoot, M.C. (2016) Both Nearest Neighbours and Long-term Affiliates Predict Individual Locations During Collective Movement in Wild Baboons. Scientific Reports 6: 27704.
3) Strandburg-Peshkin, A., Farine, D.R., Crofoot, M. C. & Couzin, I.D. (2017) Habitat and social factors shape individual decisions and emergent group structure during baboon collective movement. eLife 6:e19505.
4) Farine, D.R.*, Strandburg-Peshkin, A.*, Couzin, I.D., Berger-Wolf, T.Y., Crofoot, M.C. (2017) Individual variation in local interaction rules can explain emergent patterns of spatial organisation in wild baboons. Proceedings of the Royal Society B 284: 20162243. * joint first authors
- Project cooperation: University of Konstanz, Max Planck Institute for Ornithology (Radolfzell), Smithsonian Tropical Research Institute (Panama), Princeton University (USA), University of California, Davis (USA), University of Illinois at Chicago (USA)
- Data basis: Movement data of a group of 25 baboons living in the wild in Kenya, tracked with GPS transmitters
Note to editors:
You can download pictures here:
Caption: Movement patterns of baboons in the wild
Photo: Ariana Strandburg-Peshkin
Caption: Baboons in Kenya
Photo: Rob Nelson, Untamed Science
University of Konstanz
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Julia Wandt | idw - Informationsdienst Wissenschaft
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences | <urn:uuid:8acefd7c-8690-4c3e-bf41-80f4cd4f9bdc> | 3.859375 | 2,030 | Content Listing | Science & Tech. | 39.048965 | 95,594,118 |
Launch near for orbiter, lander bound for Mars
The ExoMars 2016 mission, a collaboration between the European and Russian space agencies, is scheduled to blast off from Kazakhstan on Monday.
The spacecraft, which consists of an orbiter that will measure methane and other gases in the Martian atmosphere and a lander to study dust storms, will hitch a ride on top of a Russian Proton rocket that is expected to lift off at 3:31 p.m. local time. The European Space Agency will broadcast coverage of the launch on the Internet beginning about an hour before liftoff.
The ExoMars spacecraft will arrive at Mars in October. Three days before arriving, the lander, named Schiaparelli, after 19th-century Italian astronomer Giovanni Schiaparelli, will separate from the orbiter. It is to enter the atmosphere at 13,000 mph and quickly decelerate on its way to settling down on the surface.
The main objective of Schiaparelli is to demonstrate its landing system. (The European Space Agency’s last attempt to land on Mars — the Beagle 2 spacecraft, which accompanied the Mars Express orbiter in 2003 — failed.)
Schiaparelli carries instruments to measure Mars’ atmosphere during the height of the dust storm season. Its batteries are expected to last only two to four days.
The Trace Gas Orbiter is to operate much longer, until at least 2022, circling Mars at an altitude of 250 miles. Its instruments will measure gases, such as methane, water vapor and nitrogen, that exist in minute quantities but could hold important clues about the possibility of life on Mars.
Methane is the most intriguing trace gas. Sunlight and chemical reactions break up methane molecules in the atmosphere. Any methane there must have been created recently, and the two possibilities for creating methane are microbes and a geological process requiring heat and liquid water.
Mars Express made tenuous detections of methane, but its instruments were not sensitive enough for definitive conclusions. NASA’s Curiosity rover also detected a transient whiff of methane in 2014.
“Methane is a hot topic,” Jorge Vago, the project scientist, said in a European Space Agency video. “So trying to understand the origin of the methane, and where on the surface of Mars, and when it’s being produced and how it is destroyed is very important.”
The ExoMars spacecraft was originally to be launched by NASA, but tight budgets led that agency to back out in 2012, and the Russians stepped in.
The second half of the ExoMars collaboration — a rover — is scheduled to launch in 2018, but that mission is expected to slip to 2020. | <urn:uuid:9026219a-60ec-4492-beb4-4a7b2ffadae2> | 2.96875 | 561 | News Article | Science & Tech. | 43.543321 | 95,594,136 |
National Institute for Environmental Studies (NIES)
Mapping the resilience of chemosynthetic communities in hydrothermal vent fields around the western Pacific Ocean
Mapping the resilience of chemosynthetic communities
in hydrothermal vent fields around the western Pacific Ocean
Hydrothermal vents support unique ecosystems populated by numerous species with unique adaptations. We aimed to determine the resilience of vent communities by investigating whether they are vulnerable or robust to natural disturbances, such as volcanic activity, and anthropogenic disturbances, such as mineral resource mining. One of the ways to assess their resilience is to measure the time required for a disturbed community to recover its original state. A mathematical model capable of predicting resilience would represent an important contribution to the management of these unique ecosystems. However, compared to most terrestrial and shallow water ecosystems, information regarding hydrothermal vent ecosystems, which are typically found at depths of over 1000 m, is limited.
We thus focused on a key factor for resilience, i.e., connectivity of vent communities through larval dispersal. This is because when most of the organisms are removed from a vent field, larval supply from other vent fields will be the prominent source for re-establishment. We used estimated larval dispersal between hydrothermal vent fields in the western Pacific Ocean and implemented it as a dispersal matrix of a population dynamics model.
By simulating disturbances to hydrothermal vent fields, we mapped recoverability of communities in 131 hydrothermal vent fields in the western Pacific Ocean. Our analysis showed substantial variation in recovery time which ranged from several years to several hundred years due to variation in regional connectivity between vent fields.
We also found that, in certain cases, simultaneous disturbance of a series of vent fields either delayed or completely prevented recovery. Our method not only revealed the distribution of recoverability of chemosynthetic communities in hydrothermal vent fields but also introduced an important starting point regarding a practical tool for conservation strategies.
This research was published on 19th June 2018 (18:00 Japan time) in Scientific Reports.
Recovery time of communities in HVFs in western Pacific Ocean.
The map was generated from digital information available at Google Earth Pro v18.104.22.16832 (https://www.google.com/intl/en/earth/; Map data: Google Earth, Image Landsat/Copernicus, Data SIO, NOAA, U.S. Navy, NGA, GEBCO).
Suzuki, K.*, Yoshida, K., Watanabe, H. and Yamamoto, H. (2018) Mapping the resilience of chemosynthetic communities in hydrothermal vent fields. Scientific Reports 8: 9364. DOI: 10.1038/s41598-018-27596-7
* corresponding author
National Institute for Environmental Studies
16-2 Onogawa, Tsukuba, Ibaraki 305-8506 Japan
kyoshida (please append ‘@nies.go.jp’ to complete the email address)
suzuki.kenta (please append ‘@nies.go.jp’ to complete the email address) | <urn:uuid:fa820a2d-b3fd-4559-90a6-a051eb384c4c> | 3.28125 | 651 | Academic Writing | Science & Tech. | 27.733053 | 95,594,173 |
On Rantt, Greg Fish explains current technological progress in developing a warp drive. While a feasible functioning spacecraft is still a long way to go, energy requirements have been brought down from "more than the energy of literally everything that exists in the universe" to "69% of America’s annual energy generation." Even with that great progress, there are some minor issues that need to be resolved.
If we can really lower the amount of energy we need to harness it for warp travel by close to 39 orders of magnitude, there are some very pressing and fundamental questions about physics that will have to be raised. And when you mess with the balance of virtual particles, some very strange things will happen involving exotic terms like “information paradox” and “monogamy of entanglement,” resulting in a very special form of radiation created by the warp bubble and affecting its inhabitants, much like what we think has to happen around the event horizon of a black hole.
It may be possible to harness it with the electromagnetic fields that created the bubble to create a feedback loop by which the warp ship can pick up its power as it accelerates, but at some point, this radiation would overwhelm any attempt to contain it and incinerate anything inside the warp bubble. So even in the best-case scenario, actually using a warp drive involves a rather delicate balancing act of enormous energies and forces that White has yet to address. But again, keep in mind that he’s yet to get this far.
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In chemistry, a trimer is a molecule or an anion formed by combination or association of three molecules or ions of the same substance. In technical jargon, a trimer is a kind of oligomer derived from three identical precursors often in competition with polymerization.
- 3 H2N-CO-NH2 → [C(O)NH]3 + 3 NH3
- (NH2)2CO → HOCN + NH3
Then in the second step, cyanic acid polymerizes to form cyanuric acid, which condenses with the liberated ammonia from the first step to release melamine and water.
- '3 HOCN → [C(O)NH]3
- [C(O)NH]3 + 3 NH3 → C3H6N6 + 3 H2O
This water then reacts with cyanic acid present, which helps drive the trimerization reaction, generating carbon dioxide and ammonia.
- 3 HOCN + 3 H2O → 3 CO2 + 3NH3
In total, the second step is exothermic:
- 6 HCNO + 3 NH3 → C3H6N6 + 3 CO2 + 3NH3
but the overall process is endothermic.
The 1,5,9-trans-trans-cis isomer of cyclododecatriene, which has some industrial importance is obtained by cyclotrimerization of butadiene with titanium tetrachloride and an organoaluminium co-catalyst:
Breaking carbon-hetero double bonds forms symmetrical saturated 1,3,5-heterocyclesEdit
1,3,5-Trithiane is the cyclic trimer of the otherwise unstable species thioformaldehyde. This heterocycle consists of a six-membered ring with alternating methylene bridges and thioether groups. It is prepared by treatment of formaldehyde with hydrogen sulfide.
Dimethylsilanediol dehydrates to a trimer of Me2SiO as well as polydimethylsiloxane. The reaction illustrates the competition between trimerization and polymerization. The polymer and trimer are formally derived from the hypothetical sila-ketone Me2Si=O, although this species is not an intermediate.
- Hillis O. Folkins (2005). "Benzene". Ullmann’s Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a03_475.
- Klaus Huthmacher, Dieter Most "Cyanuric Acid and Cyanuric Chloride" Ullmann's Encyclopedia of Industrial Chemistry" 2005, Wiley-VCH, Weinheim. doi 10.1002/14356007.a08 191
- Industrial Organic Chemistry, Klaus Weissermel, Hans-Jurgen Arpe John Wiley & Sons; 3rd 1997 ISBN 3-527-28838-4
- Bost, R. W.; Constable, E. W. "sym-Trithiane" Organic Syntheses, Collected Volume 2, p.610 (1943). "Archived copy" (PDF). Archived from the original (PDF) on 2012-03-29. Retrieved 2014-05-05.
- Bonamico, M.; Dessy, G.; Fares, V.; Scaramuzza, L. (1975). "Structural Studies of Metal Complexes with Sulphur-Containing Bidentate Ligands. Part I. Crystal and Molecular Structures of Trimeric Bis-(dithiobenzoato)-nickel(II) and -palladium(II)". Journal of the Chemical Society, Dalton Transactions: 2250–2255. doi:10.1039/DT9750002250.
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Zonobiome of the Subtropical Arid Climate with Deserts
Deserts are arid regions where potential evaporation is very much higher than annual precipitation. These regions can be further subdivided into semiarid, arid, and extremely arid, which together, cover 35% of the earth’s land surface. The cold winter period which is typical of the arid regions of the temperate zone is lacking in the subtropical desert zone (see Sect. VII).
KeywordsSaline Soil Arid Region Dwarf Shrub Desert Plant Sonoran Desert
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About this book
Carbon inventory requiring estimation of carbon dioxide emissions and removals in land-use categories for national greenhouse gas inventory and changes in stocks of carbon in projects aimed at climate change mitigation has become increasingly important in global efforts to address climate change. Hence, there is a need for a handbook that provides guidelines and methods required for carbon inventory.
Carbon Inventory Methods Handbook provides detailed step-by-step information on sampling procedures, field and laboratory measurements, application of remote sensing and GIS techniques, modeling, and calculation procedures along with sources of data for carbon inventory.
The unique feature of this handbook is that it provides practical guidance on carbon inventory methods for four kinds of projects, namely, 1) development, implementation and monitoring of carbon mitigation in forest, agriculture and grassland sectors, 2) national greenhouse gas inventory in agriculture, forest, and other land-use categories, 3) forest, grassland and agroforestry development and 4) commercial and community forestry roundwood production.
Carbon Inventory Methods Handbook is an essential source of reference to universities and research institutions dealing with climate change, consultancy and non-governmental organizations involved in developing and monitoring land-based mitigation projects, donor agencies funding carbon mitigation projects, national greenhouse gas inventory agencies, United Nations agencies and mechanisms such as Clean Development Mechanism and Global Environment Facility, roundwood production and land reclamation project developers and managers, and forest departments. | <urn:uuid:aea1f9f2-d3ff-4770-b847-9209a905a7b3> | 2.875 | 288 | Truncated | Science & Tech. | -28.423069 | 95,594,277 |
This third level OU physics course comes in three books.
Book 1: wave mechanics introduces Schrödinger’s equation and takes the reader through the standard models of particles in infinite and finite square wells, simple harmonic oscillators, and free particle wave packets. The book concludes with a first look at scattering and tunnelling, along with probability currents.
Book 2: quantum mechanics and its interpretation starts with Dirac notation and the vector space model of quantum states. The next few chapters introduce the angular momentum operators and spin followed by many-particle systems and indistinguishability, including the Pauli exclusion principle.
The final part of the book moves into the modern areas of quantum entanglement and the EPR ‘paradox', and briefly introduces quantum cryptography, quantum teleportation and a very brief mention of quantum computing.
Book 3: quantum mechanics of matter opens with a thorough analysis of the hydrogen atom. We start with spherical harmonics, then look at the radial equation (for the radial part of the wave function in spherical coordinates). This allows us to account for the spectroscopic data for hydrogen in a first approximation.
In chapter 3 we detour to study perturbation methods for solving more complex versions of the Schrödinger equation by approximation and then apply these to helium as well as developing a more sophisticated analysis of hydrogen involving the fine and hyperfine structure. We now have the tools to analyse more complex atoms with many electrons – we learn about electron shells and the Periodic Table.
Next come diatomic molecules and then an overview of the quantum treatment of bulk solids. Now we begin to understand the real differences between insulators, semiconductors and full conductors. In the final chapter we look at the interaction between atoms and electromagnetic radiation, treating the former quantum mechanically and the latter classically. And that’s it.
Some summary thoughts. SM358 is a very thorough, somewhat conservative and rather practical first course. It deliberately doesn’t get involved in populist worries about ‘the meaning of quantum mechanics’: the focus is very much on learning concepts and techniques. This is wholly to be applauded.
The concepts are of course very alien and the course material really needs to be read at least twice. The first time to ‘load the concepts’ - hard work because of their novelty. The second time to knit them together into a holistic totality. Revision for the exam is very important for this final consolidation and sufficient time needs to be budgeted.
Overall, the course is somewhat similar to the material covered in “An Introduction to Quantum Physics” by A. P. French and E. F. Taylor. I found the extra depth in this textbook sometimes helpful in illuminating concepts.
What is barely hinted at is the elevated ladder of which this course is merely the first rung. The next step would be a graduate-level 'proper' Hilbert space development of non-relativistic quantum mechanics. This would be complemented by Quantum Field Theory, which as the name suggests quantizes the classical fields and unifies quantum mechanics with special relativity to give us the Standard Model. And then there is the search for grand unification, combining the four forces of nature into one coherent framework. This takes us to quantum theories of gravity, most notably String Theory.
To climb this ladder would probably take an ambitious young physicist most of their twenties. | <urn:uuid:e091d7ad-6e33-416b-ae03-d3857473c69c> | 2.6875 | 696 | User Review | Science & Tech. | 37.466218 | 95,594,288 |
A mini-antenna for the data processing of tomorrow
With the rapid advance of miniaturization, data processing using electric currents faces tough challenges, some of which are insurmountable. Magnetic spin waves are a promising alternative for the transfer of information in even more compact chips. Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), as part of an international research venture, have now succeeded in generating spin waves with extremely short wavelengths in the nanometer range – a key feature for their future application.
Smaller, faster, more energy-efficient – this is the mantra for the further development of computers and mobile telephones which is currently progressing at a breathtaking pace. However, Dr. Sebastian Wintz of the HZDR Institute of Ion Beam Physics and Materials Research knows only too well, how difficult it already is to achieve any further degree of miniaturization. "One major problem with current technologies," he said, "is the heat which is generated when data are transmitted with the aid of electric currents. We need a new concept." The physicist is working with international colleagues on so-called spin waves (magnons) which are set to replace moving charges in the future as information carriers. The scientists have now succeeded for the first time in generating spin waves of such short wavelengths that they have potential for future applications in data processing.
Spin waves replace electric current
The spin denotes a property which lends the particles a magnetic moment. They then act like tiny magnets which run parallel to each other in ferromagnetic materials. If one of the spins then changes direction, this has a knock-on effect on its neighbors. A chain reaction gives rise to a spin wave.
The processing of information is presently based on electric currents. The charged particles speed through a network of wires which are squeezed closer and closer together, driven by the desire for ever more compact chips. On their way, the electrons collide with atoms, causing them to rock to and fro in the crystal lattice thereby generating heat. If the wires are too close together, this heat can no longer be dissipated and the system breaks down. "The great advantage of spin waves is that the electrons themselves don't move," explained Wintz, "therefore precious little heat is produced by the flow of data."
Magnetic vortex as a nano-antenna
The traditional approach adopted to generate spin waves is to use small metal antennas which generate magnons when driven by a high-frequency alternating current. The smallest wavelength which can be generated in this way will be about the size of the antenna which is used. This is precisely where the major problem lies in that small wavelengths on the nanometer scale are required in order to satisfy the demand for ever greater miniaturization. It is not currently possible, however, to make such small high-frequency antennas.
The research team from Germany, Switzerland and the USA has now succeeded in generating extremely short-wavelength spin waves in an entirely new way. As a naturally formed antenna, they use the center of a magnetic vortex which is produced in a small, ultra-thin ferromagnetic disk. Due to the disk's limited size, the spins do not all line up in parallel as normal but lie along concentric circles in the plane of the disk. This, in turn, forces the spins from a small area in the center of the disk, which measures just a few nanometers in diameter, to straighten up and, thus, to point away from the surface of the disk. If this central region is subjected to an alternating magnetic field then a spin wave is produced.
A few more tricks are needed, however, in order to shorten the wavelength as required. Consequently, a second tiny disk is placed onto the first, separated by a thin, non-magnetic layer. When this separating layer is fabricated with a specific thickness, then the two disks interact in such a way as to elicit an antiferromagnetic coupling between the disks – the spins try to point in opposite directions – which reduces the wavelength of the emitted spin waves many times over. "Only in this way do we arrive at a result which is relevant for information technology," added Wintz.
Attractive properties for applications
The scientists not only demonstrated the short wavelengths of the spin waves generated in this way but were also able to reveal other wave properties which could be very useful for future applications. With the help of high-speed movies taken with an X-ray microscope belonging to the Max Planck Institute for Intelligent Systems in Stuttgart (which is installed at the Helmholtz-Zentrum Berlin) they showed that the wavelength can be adjusted precisely by the selection of the excitation frequency. Similar measurements were also carried out at the Paul Scherrer Institute in Switzerland. The results are consistent with a theoretical model which was developed specifically for this study at Oakland University in the USA. What is more, a remarkable phenomenon was predicted, which so far has not been seen directly in the experiments: The speed at which the spin waves travel was calculated to be heavily dependent on their propagation direction (forwards or backwards) – another point which could enable a large number of applications in signal processing.
__Publication: S. Wintz, V. Tiberkevich, M. Weigand, J. Raabe, J. Lindner, A. Erbe, A. Slavin, J. Fassbender, "Magnetic vortex cores as tunable spin-wave emitters", Nature Nanotechnology, 2016, (DOI: 10.1038/nnano.2016.117)
Dr. Sebastian Wintz
Institute of Ion Beam Physics and Materials Research at the HZDR | Paul Scherrer Institute (Switzerland)
Tel. +49 351 260-2919 | +41 56 310 3638
email: [email protected] | [email protected]
Simon Schmitt | Science editor
Phone +49 351 260-3400 | Mail: [email protected]
Helmholtz-Zentrum Dresden-Rossendorf | Bautzner Landstr. 400 | 01328 Dresden | http://www.hzdr.de
The Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is conducting research in the areas of energy, health, and matter. The following set of questions provides the focal point for this research:
- How can energy and resources be utilized in an efficient, safe, and sustainable way?
- How can malignant tumors be more precisely visualized, characterized, and more effectively treated?
- How do matter and materials behave under the influence of strong fields and in smallest dimensions?
Since 2011, the HZDR has been a member of the Helmholtz Association, Germany's largest scientific organization. Some 1,100 employees are working at one of four research sites in Dresden, Leipzig, Freiberg, and Grenoble/France – approximately 500 of HZDR employees are scientists, including 150 Ph.D. students. | <urn:uuid:3162989d-1148-4c0c-b01a-b17830e3a47e> | 3.59375 | 1,439 | News (Org.) | Science & Tech. | 41.495779 | 95,594,292 |
An Ali_xGaxAs, injection laser has been employed as a reference source in a rapid scan cryogenic interferometer spectrometer. The interferometer was designed to operate at 20°K with a scan velocity of 1 cm/sec and a spectral resolution of 2 cm-1. The slide velocity control and sampling requirements for a continuous drive interferometer are discussed and those properties which are needed in choosing and calibrating an injection reference laser are given. The relative advantages and limitations of an injection reference laser are given and are related to the laser's spectral purity, threshold condition, power efficiency, and beam pattern.
Steven P. Tomczak,
"Application of the Injection Laser as a Reference Source in Cryogenic Interferometry," Optical Engineering 13(4), 134322 (1 August 1974). https://doi.org/10.1117/12.7971714 | <urn:uuid:936b8980-1c92-4f03-a0e7-833b00eca086> | 2.546875 | 184 | Truncated | Science & Tech. | 33.839737 | 95,594,307 |
Please use this identifier to cite or link to this item:
Multiple generations of grain aggregation in different environments preceded solar system body formation
|Ishii_et_al_2018_PNAS_pre-publication.pdf||13.09 MB||Adobe PDF||View/Open|
|SI_Appendix_Ishii_2018_PNAS_pre-pub.pdf||1.24 MB||Adobe PDF||View/Open|
|Title:||Multiple generations of grain aggregation in different environments preceded solar system body formation|
|Authors:||Ishii, Hope A.|
Bradley, John P.
Bechtel, Hans A.
Brownlee, Donald E.
Bustillo, Karen C.
show 4 moreCiston, James
Cuzzi, Jeffrey N.
Joswiak, David J.
|Issue Date:||11 Jun 2018|
|Publisher:||Proceedings of the National Academy of Sciences of the United States of America|
|Abstract:||The solar system formed from interstellar dust and gas in a molecular cloud. Astronomical observations show that typical interstellar dust consists of amorphous (a-) silicate and organic carbon. Bona fide physical samples for laboratory studies would yield unprecedented insight about solar system formation, but they were largely destroyed. The most likely repositories of surviving presolar dust are the least altered extraterrestrial materials, interplanetary dust particles (IDPs) with probable cometary origins. Cometary IDPs contain abundant submicron a-silicate grains called GEMS, believed to be carbon-free. Some have detectable isotopically anomalous a-silicate components from other stars, proving they are preserved dust inherited from the interstellar medium. However, it is debated whether the majority of GEMS predate the solar system or formed in the solar nebula by condensation of high-temperature (>1300K) gas. Here, we map IDP compositions with single nanometer-scale resolution and find that GEMS contain organic carbon. Mapping reveals two generations of grain aggregation, the key process in growth from dust grains to planetesimals, mediated by carbon. GEMS grains, some with a-silicate subgrains mantled by organic carbon, comprise the earliest generation of aggregates. These aggregates (and other grains) are encapsulated in lower density organic carbon matrix, indicating a second generation of aggregation. Since this organic carbon thermally decomposes above ~450K, GEMS cannot have accreted in the hot solar nebula and formed, instead, in the cold presolar molecular cloud and/or outer protoplanetary disk. We suggest that GEMS are consistent with surviving interstellar dust, condensed in situ, and cycled through multiple molecular clouds.|
|Description:||Manuscript submitted to Proceedings of the National Academy of Science|
|Sponsor:||Portions of this work were performed at the Molecular Foundry and the Advanced Light Source at Lawrence Berkeley National Laboratory, which are supported by the Office of Science, Basic Energy Sciences, U.S. Department of Energy under Contract No. DE-AC02-05CH11231. HAI acknowledges funding by NASA’s Laboratory Analysis of Returned Samples and Emerging Worlds Programs (NNX14AH86G and NNX16AK41G). JPB acknowledges funding by NASA’s Cosmochemistry Program (NNX14AI39G). CF acknowledges funding by NASA’s Cosmochemistry Program (NNX14AG25G).|
|Rights:||This is a post-print version. Published article is open access and available at http://www.pnas.org/content/early/2018/06/04/1720167115.|
|Appears in Collections:||HIGP Faculty & Researcher Works|
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Items in ScholarSpace are protected by copyright, with all rights reserved, unless otherwise indicated. | <urn:uuid:130ada71-ce9d-404e-96fb-7cfb9e79548d> | 2.875 | 844 | Academic Writing | Science & Tech. | 27.164396 | 95,594,323 |
Gene amplification is a procedure in which a certain gene or DNA sequence is replicated many times in a process called DNA replication.
In separation and detection, DNA and mRNA are isolated from cells and then detected simply by the isolation. Cell cultures are also grown to provide a constant supply of cells ready for isolation.
First, laboratories use a normal cellular modification of mRNA that adds up to 200 adenine nucleotides to the end of the molecule (poly(A) tail). Once this has been added, the cell is ruptured and its cell contents are exposed to synthetic beads that are coated with thymine string nucleotides. Because Adenine and Thymine pair together in DNA, the poly(A) tail and synthetic beads are attracted to one another, and once they bind in this process the cell components can be washed away without removing the mRNA. Once the mRNA has been isolated, reverse transcriptase is employed to convert it to single-stranded DNA, from which a stable double-stranded DNA is produced using DNA polymerase. Complementary DNA (cDNA) is much more stable than mRNA and so, once the double-stranded DNA has been produced it represents the expressed DNA sequence scientists look for.
This technique is used to identify which genes or genetic mutations produce a certain phenotype. A mutagen is very often used to accelerate this process. Once mutants have been isolated, the mutated genes can be molecularly identified.
Forward saturation genetics is a method for treating organisms with a mutagen, then screens the organism's offspring for particular phenotypes. This type of genetic screening is used to find and identify all the genes involved in a trait.
A mutation in a gene can cause encoded proteins and the cells that rely on those proteins to malfunction. Conditions related to gene mutations are called genetic disorders. However, altering a patient's genes can sometimes be used to treat or cure a disease as well. Gene therapy can be used to replace a mutated gene with the correct copy of the gene, to inactivate or knockout the expression of a malfunctioning gene, or to introduce a foreign gene to the body to help fight disease. Major diseases that can be treated with gene therapy include viral infections, cancers, and inherited disorders, including immune system disorders.
Gene therapy delivers a copy of the missing, mutated, or desired gene via a modified virus or vector to the patient's target cells so that a functional form of the protein can then be produced and incorporated into the body. These vectors are often siRNA. Treatment can be either in vivo or ex vivo. The therapy has to be repeated several times for the infected patient to continually be relieved, as repeated cell division and cell death slowly randomizes the body's ratio of functional-to-mutant genes. Gene therapy is an appealing alternative to some drug-based approaches, because gene therapy repairs the underlying genetic defect using the patients own cells with minimal side effects. Gene therapies are still in development and mostly used in research settings. All experiments and products are controlled by the U.S. FDA and the NIH. | <urn:uuid:c9da4d84-91b8-4efa-aa5f-2c770fd40ba0> | 4.125 | 619 | Knowledge Article | Science & Tech. | 32.658254 | 95,594,325 |
Hairspray might one day serve as the sign that aliens have reshaped distant worlds, researchers say. Such research to find signs of alien technology is now open to funding from the public.
Science fiction has long imagined that humans could transform hostile alien worlds into livable ones, a procedure known as terraforming. For instance, to colonize Mars, scientists have suggested warming the red planet and thickening its extraordinarily thin atmosphere so that humans can roam its surface without having to wear spacesuits. To do so, plans to terraform Mars often involve vast amounts of greenhouses gases to trap enough heat from the Sun, forcing carbon dioxide frozen on the planet's surface to turn into gas.
If humans might one day terraform planets, aliens with more advanced technology might have already done so. If that's the case, astronomers could look for telltale signs of such changes to reveal that intelligent extraterrestrial life exists.
"Our hypothesis is that evidence of intelligent life might be evident in a planetary atmosphere," said astrobiologist Mark Claire at the Blue Marble Space Institute of Science, a nonprofit network of scientists across the world.
One group of gases that might be key to terraforming planets are chlorofluorocarbons (CFCs). These nontoxic, long-lived chemicals are strong greenhouse gases and were once often used in hairspray and air conditioners, among many other products.
CFCs are entirely artificial, with no known natural process capable of creating them in atmospheres. Detecting signs of these gases on far-off worlds with telescopes might serve as potent evidence that intelligent alien civilizations were the cause, either intentionally as part of terraforming or accidentally via industrial pollution.
"An industrialized civilization will be one that will use its planetary resources for fabrication, the soon-to-be-detectable-from-Earth atmospheric byproducts of which could be a tell-tale sign of their activity," said astrobiologist Sanjoy Som of the Blue Marble Space Institute of Science.
Telescopes have currently helped spot hundreds of exoplanets so far and should help detect hundreds more soon. Future observatories could analyze the atmospheres of these worlds, and CFCs should be easy to see, because the way they absorb light is very different from naturally-occurring chemicals.
"We are on the scientific verge of being able to actively look for extrasolar worlds inhabited by technological civilizations," Som said. "We are about a decade away of being able to measure detailed compositions of the atmospheres of extrasolar planets."
Using state-of-the-art computer models of atmospheric chemistry and climate, the researchers plan to discover what visible signs CFCs and other artificial byproducts of alien terraforming or industry might have on exoplanet atmospheres.
"We will then test if these features are detectable over interstellar distances, by severely downgrading our computed signal to mimic the signal quality of next-generation telescopes," Claire said.
Scientists worldwide could then use this data to see if any of the exoplanets discovered so far or to come show evidence of these "technosignatures."
"This SETI proposal is about looking at atmospheric chemistry rather than other previously proposed technosignatures like radio signals or pulsed light beams," Claire said.
Claire added that sulfur hexaflouride is another industrial molecule and greenhouse gas that could serve as a technosignature. Other technosignatures may include unusually large amounts of ammonia or carbon dioxide, when observed alongside gases such as oxygen and water vapor, which are often thought to be common signs of life, Som said.
"This project will move forward only if it is funded. We invite the public to take part and be included in our adventures by pledging a small amount of money to our efforts," Som said. "We are a small 501(c)3 non-profit science organization with a strong emphasis in science communication. All donations are tax-deductible!"
This research could also help astrobiologists discover signs of alien intelligence outside the so-called habitable zones where hunts for extraterrestrial life is often most focused on. There is life virtually wherever there is liquid water on Earth, so habitable zones are often thought of as the areas around stars where liquid water can persist on a planet's surface, given temperatures that are neither too hot nor too cold.
"Artificially warming a body outside of the habitable zone to make it habitable could also be a tell-tale sign of intelligence," Som said. "For example, suppose that in a few thousand years, humans have terraformed Mars. Suppose that an alien species is observing our solar system and finds Earth. In addition, it measures the atmospheric composition of Mars, a planet essentially outside the habitable zone of our sun, and finds elevated greenhouses gasses in addition to water vapor and oxygen. This two-planet system would be a strong indication to them of an intelligent civilization at work expanding its cradle outside of its home planet."
This may be the first scientific investigation of what a terraformed planet might look like from afar, and could be a new tool in the search for extraterrestrial intelligence (SETI). It goes without saying that if these efforts help discover intelligent alien life, "the implications will be tremendous, as it will cause a major reassessment of what it means to be human," Som said.
Image courtesy of Flickr, Futurilla
- 7 Far-Out Summer Vacation Ideas for Science Fiction Fans
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This article originally published at Space.com here | <urn:uuid:ae51b67e-c32c-4529-b1a4-c32f330cca23> | 3.515625 | 1,176 | News Article | Science & Tech. | 25.091871 | 95,594,327 |
Lake Okeechobee’s receding water is offering a clearer view of Irma’s environmental impact.
The water is down by about a foot since the hurricane but remains high at more than 16 feet.
Paul Gray of Audubon of Florida says the water and muck stirred from the lake’s bottom prevent sunlight from reaching important plant communities.
And those plants serve as nurseries for fish.
“You have a huge loss in the lake. You lose the plant communities. You lose the bass fishery, and the crappie fishery tends to tank, too. And it may not come back for years because we just have to sit around and wait for a drought.”
He says the state’s largest lake could lose as many as 70 square miles of vegetation although the full scope of the hurricane’s impact won’t be known for months.
Lake Okeechobee serves as the hydrological heart of the Everglades, a watershed that supports the drinking water for more than a third of Floridians. | <urn:uuid:f60ad2b8-8f50-44b8-a15d-ec4b5524ca05> | 3.53125 | 226 | News Article | Science & Tech. | 59.861571 | 95,594,349 |
|Add Memory | Add To Friends|
|0ona (profile) wrote, |
on 6-1-2009 at 6:22pm
|Subject: ::The cloud with no name: Meteorologists campaign to classify unique 'Asperatus' clouds seen across the world::
|By Luke Salkeld
01st June 2009
Whipped into fantastical shapes, these clouds hang over the darkening landscape like the harbingers of a mighty storm
But despite their stunning and frequent appearances, the formations have yet to be officially recognised with a name.
They have been seen all over Britain in different forms - from Snowdonia to the Scottish Highlands - and in other parts of the world such as New Zealand, but usually break up without producing a storm.
And some experts believe the stormy weather phenomenon deserves its very own classification.
Experts at the Royal Meteorological Society are now attempting to make it official by naming it 'Asperatus' after the Latin word for 'rough'.
If they are successful, it would be the first variety of cloud formation to be given a new label in over half a century
'It is a bit like looking at the surface of a choppy sea from below,' said Gavin Pretor-Pinney, founder of the Cloud Appreciation Society, who identified the cloud from photographs sent in by members.
'We try to identify and classify all of the images of clouds we get in, but there were some that just didn't seem to fit in any of the other categories, so I began to think it might be a unique type of cloud.'
He added: 'The underside of the clouds are quite rough and choppy. It looks very stormy, but some of the reports we have been getting suggest that they tend to break up without actually turning into a storm.'
The Royal Meteorological Society is now gathering detailed information for the days and locations where the asperatus clouds have been seen in an attempt to understand exactly what is causing them.
Officials will then apply to the UN's World Meteorological Organisation in Geneva to have the new cloud type considered for addition into the International Cloud Atlas, the system used by meteorologists across the globe.
Professor Paul Hardaker, Chief Executive of the RMS, said: 'There would probably need to be quite a lot of heat around to produce the energy needed to generate such dramatic cloud formations.
'They are quite dark structures so there must be a lot of water vapour condensing in the cloud.'
Skies over Scotland: This scene from Perthshire could help confirm the new 'Asperatus' classification
To see more examples of unusual types of clouds, including a section on cloud art and music to watch clouds by, visit: cloudappreciationsociety.org
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Object Oriented Programming in ANSI-C
by Axel Schreiner
Number of pages: 252
This book is not going to praise object-oriented programming or condemn the Old Way. We are simply going to use ANSI-C to discover how object-oriented programming is done, what its techniques are, why they help us solve bigger problems, and how we harness generality and program to catch mistakes earlier. Along the way we encounter all the jargon - classes, inheritance, instances, linkage, methods, objects, polymorphisms, and more - but we take it out of the realm of magic and see how it translates into the things we have known and done all along.
Home page url
Download or read it online for free here:
by Al Aho, Jeff Ullman - W. H. Freeman
Aho and Ullman have created a C version of their groundbreaking text. This book combines the theoretical foundations of computing with essential discrete mathematics. It follows the same organizations, with all examples and exercises in C.
by David A. Curry - O'Reilly
'Using C on the UNIX System' provides a thorough introduction to the UNIX system call libraries. This book is aimed at programmers who already know C, but who want to take full advantage of the UNIX programming environment.
by Simon Long - Raspberry Pi Ltd.
Learn to code with C across 13 packed chapters: Create variables and do arithmetic; Control the flow of your C programs; For loops and case statements; Understand and create functions; Work with arrays and strings; and much more.
by JT Kalnay - Smashwords
The author included example programs that exhaustively illustrate the important points of C. By working through these programs you can teach yourself C. It is assumed that you already know how to program and are familiar with standard algorithms. | <urn:uuid:528fc4ae-bae6-48c8-a51c-1eb73f1283ab> | 3.15625 | 378 | Product Page | Software Dev. | 50.349681 | 95,594,362 |
Stacking of microbial fuel cells (MFC) by connecting multiple small-sized units in a series is used for generating higher power from the MFCs. However, voltage reversal is a critical problem in a serially connected MFC unit. The voltage reversal often occurs when substrate concentration is relatively low in the anodic compartment. Two rectangular individual cells were stacked together in series: MFC1 was fed with 1 g glucose L(-1) throughout the experiment while MFC2 was fed with various concentrations of glucose (0.1, 0.2, 0.3, 0.5 and 0.8 g L(-1)). Voltage reversal occurred when the stack configuration was performed using (1 + 0.1) g glucose L(-1). The stacked configurations with (1 + 0.2, 1 + 0.3, 1 + 0.5 and 1 + 0.8) g glucose L(-1) were operated successfully without the voltage reversal. The maximum powers of 1.88, 2.04, 3.6, 2.5 and 2.18 mW were obtained with the stacked configurations of (1 + 0.2), (1 + 0.3), (1 + 0.5), (1 + 0.8) and (1 + 1) g glucose L(-1), respectively. Except in the stacked configuration with (1 + 0.1) g glucose L(-1), the stacked voltages obtained were similar.
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- 1 Deformation styles
- 2 Geological environments associated with strike-slip tectonics
- 3 See also
- 4 References
- 5 External links
Riedel shear structures
In the early stages of strike-slip fault formation, displacement within basement rocks produces characteristic fault structures within the overlying cover. This will also be the case where an active strike-slip zone lies within an area of continuing sedimentation. At low levels of strain the overall simple shear causes a set of small faults to form. The dominant set, known as R shears, form at about 15° to the underlying fault with the same shear sense. The R shears are then linked by a second set, the R' shear that form at about 75° to the main fault trace. These two fault orientations can be understood as conjugate fault sets at 30° to the short axis of the instantaneous strain ellipse associated with the simple shear strain field caused by the displacements applied at the base of the cover sequence. With further displacement the Riedel fault segments will tend to become fully linked, often with the development of a further set of shears known as 'P shears', which are roughly symmetrical to the R shears with respect to the overall shear direction, until a throughgoing fault is formed. The somewhat oblique segments will link downwards into the fault at the base of the cover sequence with a helicoidal geometry.
In detail many strike-slip faults at surface consist of en echelon and/or braided segments in many cases probably inherited from previously formed Riedel shears. In cross-section the displacements are dominantly reverse or normal in type depending on whether the overall fault geometry is transpressional (i.e. with a small component of shortening) or transtensional (with a small component of extension). As the faults tend to join downwards onto a single strand in basement, the geometry has led to these being termed flower structure. Fault zones with dominantly reverse faulting are known as positive flowers, those with dominantly normal offsets are known as negative flowers. The identification of such structures, particularly where positive and negative flowers are developed on different segments of the same fault, are regarded as reliable indicators of strike-slip.
Strike slip duplexes
Strike slip duplexes occur at the step over regions of faults, forming a lens shaped near parallel arrays of horses. These occur between two or more large bounding faults which usually have large displacement.
An idealized strike-slip fault runs in a straight line with a vertical dip and has only horizontal motion, thus there is no change in topography due to motion of the fault. In reality, as strike slip faults become large and developed, their behavior changes and becomes more complex. A long strike slip fault follows a staircase-like trajectory consisting of interspaced fault planes that follow the main fault direction. These sub parallel stretches are isolated by offsets at first, but over long periods of time they can become connected by step overs in order to accommodate the strike slip displacement. In long stretches of strike-slip the fault plane can start to curve, giving rise to structures similar to step overs.
Right lateral motion of a strike slip fault at a right step over (or overstep) gives rise to extensional bends characterised by zones of subsidence, local normal faults, and pull apart basins. On extensional duplexes, normal faults will accommodate the vertical motion, creating negative relief. Similarly, left stepping at a dextral fault generates contractional bends; shortening the step overs which is displayed by local reverse faults, push-up zones, and folds. On contractional duplex structures, thrust faults will accommodate vertical displacement rather than being folded, as the uplifting process is more energy efficient.
Strike slip dulexes are passive structures; they form as a response to displacement of the bounding fault rather than by the stresses from plate motion. Each horse has a length that varies from half to twice the spacing between the bounding fault planes. Depending on the properties of the rocks and the fault, the duplexes will have different length ratios and will develop on either major or subtle offsets, although it is possible to observe duplex structures that develop on nearly straight fault segments. Because the motion of the duplexes may be heterogeneous, the individual horses can experience a rotation with a horizontal axis, which results in the formation of scissor faults. Scissor faults exhibit normal motion at one end of the horse and a thrust motion ant the other end. Because strike slip duplexes structures have more horizontal motion than vertical motion, they are best observed on a map rather than a vertical projection, and are a good indication that the main fault has a strike slip motion.
An example of strike slip duplexes were observed in the Lambertville sill, New Jersey. Flemington and the Hopewell faults, the two main faults in the region, experienced 3 km of dip slip and over 20 km of strike slip motions to accommodate regional extension. It is possible to trace the lensoidal structures which are interpreted as horses that form duplexes. The lens structures observed in the 3M quarry are 180 meters long and 10 meters wide. The main duplex is 30 m in length and other smaller duplexes are also present.
Geological environments associated with strike-slip tectonics
Areas of strike-slip tectonics are associated with:
Oceanic transform boundaries
Mid-ocean ridges are broken into segments offset from each other by transform faults. The active part of the transform links the two ridge segments. Some of these transforms can be very large, such as the Romanche fracture zone, whose active portion extends for about 300 km.
Continental transform boundaries
Transform faults within continental plates include some of the best known examples of strike-slip structures, such as the San Andreas Fault, the Dead Sea Transform, the North Anatolian Fault and the Alpine Fault.
Lateral ramps in areas of extensional or contractional tectonics
Major lateral offsets between large extensional or thrust faults are normally connected by diffuse or discrete zones of strike-slip deformation allowing transfer of the overall displacement between the structures.
Zones of oblique collision
In most zones of continent-continent collision the relative movement of the plates is oblique to the plate boundary itself. The deformation along the boundary is normally partitioned into dip-slip contractional structures in the foreland with a single large strike-slip structure in the hinterland accommodating all the strike-slip component along the boundary. Examples include the Main Recent Fault along the boundary between the Arabian and Eurasian plates behind the Zagros fold and thrust belt, the Liquiñe-Ofqui Fault that runs through Chile and the Great Sumatran fault that runs parallel to the subduction zone along the Sunda Trench.
The deforming foreland of a zone of continent-continent collision
The process sometimes known as indenter tectonics, first elucidated by Paul Tapponnier, occurs during a collisional event where one of the plates deforms internally along a system of strike-slip faults. The best known active example is the system of strike-slip structures observed in the Eurasian plate as it responds to collision with the Indian plate, such as the Kunlun fault and Altyn Tagh fault.
- Katz, Y.; Weinberger R.; Aydin A. (2004). "Geometry and kinematic evolution of Riedel shear structures, Capitol Reef National Park, Utah" (PDF). Journal of Structural Geology. 26 (3): 491–501. Bibcode:2004JSG....26..491K. doi:10.1016/j.jsg.2003.08.003. Retrieved 6 May 2011.[permanent dead link]
- Tchalenko, J.S. (1970). "Similarities between Shear Zones of Different Magnitudes". Geological Society of America Bulletin. 81 (6): 1625–1640. Bibcode:1970GSAB...81.1625T. doi:10.1130/0016-7606(1970)81[1625:SBSZOD]2.0.CO;2. Retrieved 6 May 2011.
- Ueta, K.; Tani, K. 2001. Ground Surface Deformation in Unconsolidated Sediments Caused by Bedrock Fault Movements: Dip-Slip and Strike-Slip Fault Model Test and Field Survey. American Geophysical Union, Fall Meeting 2001, abstract #S52D-0682
- Harding, T.P. 1990. Bulletin American Association of Petroleum Geologists. 74
- Keary, P. (2009), Global Tectonics, 3, ISBN 1-118-68808-2
- Woodcock, Nigel (1986), "Strike-slip duplexes", Journal of Structural Geology, 8 (7): 725–735, Bibcode:1986JSG.....8..725W, doi:10.1016/0191-8141(86)90021-0
- Burg (1986), Strike-slip and oblique-slip tectonics (PDF)
- Laney, A. (1996), "Three-dimensional shuffling of horses in a strike-slip duplex: an example from the Lambertville sill, New Jersey", Tectonophysics, 258: 53, Bibcode:1996Tectp.258...53L, doi:10.1016/0040-1951(95)00173-5
- Talebian, M. Jackson, J. 2004. A reappraisal of earthquake focal mechanisms and active shortening in the Zagros mountains of Iran Geophysical Journal International, 156, pages 506–526
- Tapponnier, P. & Molnar, P. 1979. Active faulting and Cenozoic tectonics of the Tien Shan, Mongolia and Baykal regions. Journal Geophysical Research, 84, B7, 3425 – 3459. Archived 2011-06-06 at the Wayback Machine. | <urn:uuid:d5c10daa-c0c7-41ad-b2e6-860741c95e90> | 3.75 | 2,126 | Knowledge Article | Science & Tech. | 52.035738 | 95,594,381 |
Environmental conservation and its sustainability have been increasingly important issue throughout the world.
The ecology friendly environment is one of the burning needs of today’s world if we want to sustain the human species and the quality of living on this planet.
Although the effects of the human on the environment may not be clearly seen in day to day life, the accumulated impact over the time is quite evident. The ozone layer depletion, rapidly changing weather patterns and rising earth’s temperature are some of the obvious negative impacts caused by humanity.
Conservation of ecological system comes hand in hand with environmental sustainability. There are numerous known and unknown factors which help preserve a sound ecological system of which we human are just a small part.
Every part of the ecosystem is equally important for every species in it to live and thrive in harmony, call it environment if you will.
The process of evolution supports the fact that the environmental disruption may drive species to extinction. Humans could be responsible for the extinction of the most of the world’s mammals around 14,000 years ago.
Could the Homo-sapiens be responsible for the extinction of twelve other human species which coexisted around the same time?
Likewise, plenty of evidence from the past explains that humans had great impact on environment since the dawn of modern civilization. European colonialism and imperialism caused impacts by treating the nature as mere exploitable resource all around the world. In more recent times, the environment has been greatly affected by the rise of industrialization, with very little sense of nature conservation, sustainable growth and ecological harmony.
Although, the theory of evolution argues that only the fittest can survive in this competitive world, it should not be forgotten that, the competitive world includes nature as well and also for the evolution to take place we should let the environment make the natural selection and not the other way round.
We, as conscious, sane and sensible human beings, should highly avoid intervening with the environment and its natural harmony by spreading pesticides, herbicides, chemical wastes and pollutants.
We might be the fittest species on the face of the planet but that surely does not give us right to disrupt the ecological cycles, prevailing here for millennia.
Threatening environmental harmony might drive us towards extinction for the nature might choose not to select us after all.
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Species Detail - Petalonia zosterifolia - Species information displayed is based on all datasets.
Terrestrial Map - 10kmDistribution of the number of records recorded within each 10km grid square (ITM).
Marine Map - 50kmDistribution of the number of records recorded within each 50km grid square (WGS84).
13 April (recorded in 1978)
31 December (recorded in 1994)
National Biodiversity Data Centre, Ireland, Petalonia zosterifolia, accessed 23 July 2018, <https://maps.biodiversityireland.ie/Species/234> | <urn:uuid:f0b522e7-52db-4ab5-a605-8e172d8de60e> | 2.703125 | 129 | Structured Data | Science & Tech. | 32.210609 | 95,594,436 |
A vector-valued function, also referred to as a vector function, is a mathematical function of one or more variables whose range is a set of multidimensional vectors or infinite-dimensional vectors. The input of a vector-valued function could be a scalar or a vector. Vector-valued functions provide a useful method for studying various curves both in the plane and in three-dimensional space. We can apply this concept to calculate the velocity, acceleration, arc length, and curvature of an object’s trajectory. In this chapter, we examine these methods and show how they are used.
- 13.0: Prelude to Vector-Valued Functions
- Halley’s Comet follows an elliptical path through the solar system, with the Sun appearing at one focus of the ellipse. This motion is predicted by Johannes Kepler’s first law of planetary motion, which we mentioned briefly previously. Kepler’s third law of planetary motion can be used with the calculus of vector-valued functions to find the average distance of Halley’s Comet from the Sun.
- 13.1: Vector-Valued Functions and Space Curves
- Our study of vector-valued functions combines ideas from our earlier examination of single-variable calculus with our description of vectors in three dimensions from the preceding chapter. In this section, we extend concepts from earlier chapters and also examine new ideas concerning curves in three-dimensional space. These definitions and theorems support the presentation of material in the rest of this chapter and also in the remaining chapters of the text.
- 13.2: Calculus of Vector-Valued Functions
- To study the calculus of vector-valued functions, we follow a similar path to the one we took in studying real-valued functions. First, we define the derivative, then we examine applications of the derivative, then we move on to defining integrals. However, we will find some interesting new ideas along the way as a result of the vector nature of these functions and the properties of space curves.
- 13.3: Arc Length and Curvature
- In this section, we study formulas related to curves in both two and three dimensions, and see how they are related to various properties of the same curve. For example, suppose a vector-valued function describes the motion of a particle in space. We would like to determine how far the particle has traveled over a given time interval, which can be described by the arc length of the path it follows.
- 13.4: Motion in Space
- We have now seen how to describe curves in the plane and in space, and how to determine their properties, such as arc length and curvature. All of this leads to the main goal of this chapter, which is the description of motion along plane curves and space curves. We now have all the tools we need; in this section, we put these ideas together and look at how to use them.
- 13.E: Vector-Valued Functions (Exercises)
- These are homework exercises to accompany Chapter 13 of OpenStax's "Calculus" Textmap.
Gilbert Strang (MIT) and Edwin “Jed” Herman (Harvey Mudd) with many contributing authors. This content by OpenStax is licensed with a CC-BY 3/0 license. Download for free at http://cnx.org/contents/fd53eae1-fa2...firstname.lastname@example.org. | <urn:uuid:405b2e14-3069-4ee8-b924-f0e16663a1af> | 3.890625 | 719 | Tutorial | Science & Tech. | 51.304422 | 95,594,437 |
What is Enzyme Catalysis ?
What is enzyme ? Enzymes are organic molecules, pretentious in nature that re specialized to catalyze biological reactions. Here these can be termed as “Biological Catalysts” (or) “Biocatalysts” (or) “Middle man of the Nature”.
What is Enzyme ? What is the meaning?
The name ‘enzyme‘ (enG=in; zymeG=Yeast) literal means “in yeast“. This was referred to denote one of the most noteworthy reactions where in the production of ethyl alcohol and carbon dioxide through the agency of an enzyme, the zymase, present in yeast takes place. This reaction is most popularly known as “Alcoholic fermentation”.
Today nearly 2000 different enzymes are known and 200 enzymes have been crystallized from catalytic power and specificity are the most sticking characteristics of enzymes. Activity of most of enzymes are regulated. Enzymes accelerated biochemical reactions by factors of a million or more. In fact, in the absence of enzymes, most of the reactions in biological systems do not occur at perceptible rates. As example, the catalytic activity of carbonic anhydrase can be cited; hydration of carbon dioxide (CO2) into carbonic acid is brought about y carbonic anhydrase, this is one of the fastest enzyme. Each enzyme molecule can hydrate 105 molecules of CO2 per second. The same reaction without the enzyme will be 107 times slower than the catalytic reaction.
What is Enzyme Catalysis ?
A catalyst is a chemical that increases the rate of a chemical reaction without itself being changed by the reaction. The fact that they aren’t changed by participating in a reaction distinguishes catalysts from substrates, which are the reactants on which catalysts work. Enzymes catalyze biochemical reactions. They are similar to other chemical catalysts in many ways:
- Enzymes and chemical catalysts both affect the rate but not the equilibrium constant of a chemical reaction. Reactions proceed downhill energetically, in accord with the Second Law of Thermodynamics. Catalysts merely reduce the time that a thermodynamically favored reaction requires to reach equilibrium. Remember that the Second Law of Thermodynamics tells whether a reaction can occur but not how fast it occurs.
- Enzymes and chemical catalysts increase the rate of a chemical reaction in both directions, forward and reverse. This principle of catalysis follows from the fact that catalysts can’t change the equilibrium of a reaction. Because a reaction at equilibrium occurs at the same rate both directions, a catalyst that speeds up the forward but not the reverse reaction necessarily alters the equilibrium of the reaction.
- Enzymes and chemical catalysts bind their substrates, not permanently, but transiently—for a brief time. There is no action at a distance involved. The portion of an enzyme that binds substrate and carries out the actual catalysis is termed the active site.
Enzymes differ from ordinary chemical catalysts in several important respects:
- Enzymes are specific: Chemical catalysts can react with a variety of substrates. For example, hydroxide ions can catalyze the formation of double bonds and also the hydrolysis of esters. Usually enzymes catalyze only a single type of reaction, and often they work only on one or a few substrate compounds.
- Enzymes work under mild conditions: Chemical catalysts often require high temperature and/or pressure to function. For example, nitrogen can be reduced to ammonia industrially by the Haber process, catalyzed by iron at 500° C. and at 300 atmospheres pressure of N2. In contrast, the same reaction is carried out enzymatically at 25°C. and less than 1 atmosphere pressure of N2. These gentle conditions of temperature, pressure, and pH characterize enzymatic catalysis, especially within cells.
- Enzymes are stereospecific: Chemical catalysis of a reaction usually leads to a mixture of stereoisomers. For example, the addition of acid-catalyzed water to a double bond leads to an equimolar (50:50) mixture of D and L isomers where the water is added. In contrast, catalysis of water addition by enzymes results in complete formation of either the D or L isomer, but not both.
- Enzymes are macromolecules: The macromolecules are composed of protein, or in a few cases, RNA. Most chemical catalysts are either surfaces, for example, metals like platinum, or else small ions, such as hydroxide ions.
- Enzymes are often regulated: The regulation occurs either by the concentration of substrates, by binding small molecules or other proteins, or by covalent modification of the enzymes’ amino acid side chains. Thus, an enzyme’s effectiveness can be altered without changing the concentration of the enzyme; on the other hand, the effectiveness of a chemical catalyst is generally determined by its overall concentration.
Although a huge number of reactions occur in living systems, these reactions fall into six types of enzyme catalysis reactions. The reactions are:
1. Oxidation and reduction: This is the frequently abundant enzyme catalysis reactions in metabolism. Enzymes that carry out these reactions are called oxidoreductases. For example, alcohol dehydrogenase converts primary alcohols to aldehydes. In the given reaction, ethanol is converted to acetaldehyde, and the cofactor, NAD, is converted to NADH. In other words, ethanol is oxidized, and NAD is reduced. (The charges don’t balance, because NAD has some other charged groups.) Remember that in redox reactions, one substrate is oxidized and one is reduced.
2. Group transfer reactions: These enzymes, called transferases, move functional groups from one molecule to another. For example, alanine aminotransferase shuffles the alpha-amino group between alanine and aspartate: Other transferases move phosphate groups between ATP and other compounds, sugar residues to form disaccharides, and so on.
3. Hydrolysis: These enzymes, termed hydrolases, break single bonds by adding the elements of water. For example, phosphatases break the oxygen-phosphorus bond of phosphate esters:
4.Formation or removal of a Double bond with group transfer: The functional groups transferred by these lyase enzymes include amino groups, water, and ammonia. For example, decarboxylases remove CO2 from alpha- or beta-keto acids: Dehydratases remove water, as in fumarase (fumarate hydratase):
5.Isomerization of functional groups: In many biochemical reactions, the position of a functional group is changed within a molecule, but the molecule itself contains the same number and kind of atoms that it did in the beginning. In other words, the substrate and product of the reaction are isomers. The isomerases (for example, triose phosphate isomerase, shown following), carry out these rearrangements.6. Single bond formation by eliminating the elements of water: Hydrolases break bonds by adding the elements of water; ligases carry out the converse reaction, removing the elements of water from two functional groups to form a single bond. Synthetases are a subclass of ligases that use the hydrolysis of ATP to drive this formation. For example, aminoacyl-transfer RNA synthetases join amino acids to their respective transfer RNAs in preparation for protein synthesis; the action of glycyl-tRNA synthetase is illustrated in this figure:Deaminases remove ammonia, for example, in the removal of amino groups from amino acids:
Enzyme catalysis is important aspect in enzymology and in all biological science areas.
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On May 19, 2011, the Mississippi River reached a historic crest at Vicksburg. According to the Advanced Hydrological Prediction Service (AHPS) of the U.S. National Weather Service, the river reached 57.10 feet (17.40 meters) that day. By early June, flooding had receded considerably around Vicksburg, but water remained high.
The Landsat 5 satellite Thematic Mapper captured this images on June 11, 2011. In this false-color images, water is navy blue. Depending on land use, land above water is green or burnt orange. The image is rotated, with the left sides facing north. Credit: Credit: NASA Earth Observatory images created by Jesse Allen and Robert Simmon, using Landsat data provided by the United States Geological Survey
On June 14, the AHPS reported that the Mississippi River reached 44.88 feet (13.68 meters) at Vicksburg. At that point, the river was in minor flood stage, and its level was forecast to continue falling through June 19.
The Landsat series of satellites is used by emergency managers to acquire a range of imagery, from floods to fires. Landsat has recently provided both images of the flooding of the Mississippi River and the fires raging in Arizona.
The Landsat Program is a series of Earth-observing satellite missions jointly managed by NASA and the U.S. Geological Survey. Landsat satellites have been consistently gathering data about our planet since 1972. They continue to improve and expand this unparalleled record of Earth's changing landscapes, for the benefit of all. The next Landsat satellite is scheduled to launch in December 2012.
Rob Gutro | EurekAlert!
New research calculates capacity of North American forests to sequester carbon
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Scientists discover Earth's youngest banded iron formation in western China
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For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
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Metals are good conductors of electricity because
On a clean glass plate a drop of water spreads to form a thin layer whereas a drop of mercury remains almost spherical because: A. mercury is a metal.
Why Are Metals Good Conductors of Electricity? - Reference.com
Metals are good conductors of electricity, because they have free electrons. These free electrons act as charge carriers in the metallic structure, allowing electric current to flow through the metal. Continue Reading.
Why are Metals Good Conductors of Electricity?
Which Metals are Good Conductors of Electricity? Almost all existing metallic elements are conductor of electricity, although the conductance varies according to the element.
Why are metals good conductors of electricity? - theFAQs.org
Metals are good conductors of electricity, because they allow electric charge to flow freely through them. According to BBC, metals contain a sea of delocalized electrons that are able to move throughout the metal structure.
Metals are good conductors of electricity because A metal... - eNotes
Electric current is the flow of electrons. Metals are good conductors of electricity because their valence electrons are delocalised. This means that the valence electrons are not tightly associated to a single atom, but can move through the entire metal.
What Metals Make Good Conductors of Electricity? - Sciencing
Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons). For a material to be a good conductor, the electricity passed through it must be able to move the electrons; the more free electrons in a metal, the greater its conductivity.
Metals are good conductors of electricity because - Brainly.in
So because of Sea of electrons , these electrons jst not belong to one atom bt move freely in the metal's network ...which make them great conductors of electricity.also because they contain orbitals which are separated by small energy diffrences...
Why is a metal a good conductor of electricity? - Quora
Because charge (from electricity) requires movement of electrons, metal can conduct electricity or charge rather easily by providing the electrons required to move, thus
Solved: Metals Are Good Conductors Of Electricity Because
home / study / science / physics / physics questions and answers / Metals Are Good Conductors Of Electricity Because.
SOLUTION: Metals are good conductors of electricity because...
Metals are good conductors of electricity because the electrons are free to move in a network of metal atom.
Conductivity and Conductive Elements
Although it is the best conductor, copper and gold are used more often in electrical applications because copper is less expensive and gold has a much higher corrosion resistance.
Why metals are good conductors of electricity? - Socratic
Metals are excellent conductors because the atoms in a metal form a matrix through which their outer electrons can move freely. Instead of orbiting their respective metal atoms, they form a "sea" of electrons that surrounds the positively charged atomic nuclei of the interacting metal ions .
Metals are such good conductors of heat and electricity all because...
Why are metals good conductors of heat and electricity? Because the way they are molecularly bonded, having free moving electrons within their structure to do all the work.
Metals are good conductors of electricity because - Competoid...
-- View Answer. 5). The oath of office is conducted to the president by. A). the speaker of Lok Sabha.
Which Metals Conduct Electricity? - Metal Supermarkets - Steel...
While all metals can conduct electricity, certain metals are more commonly used due to being highly conductive.
Explain briefly why metals are good conductors of electricity
Metals are good electrical conductors because the bonds between metals have free electrons, guaranteeing a transit free of temperature and heat. We can note the effectiveness of metal conducts, for example, in the preparation of food: in pans.
Why are metals good conductors of electricity and heat?
As the atoms vibrate more with kinetic energy (heat), they are able to pass that energy through the material more easily. Metals are good conductors of electricity and heat because they have free electrons that can carry an electrical charge or heat energy through the metal.
Why Are Metals Good Conductors of Electricity? - Asdnyi
Metals are good conductors of electricity, because they have free electrons. These free electrons act as charge carriers in the metallic structure, allowing electric current to flow through the... BBC Th.
good conductor of electricity - English examples in context - Ludwig
English sentences with good conductor of electricity in context. No results, please check your input for typos or set a different source language 9 exact
Ответы@Mail.Ru: помогите перевести обычный переводчик не...
Almost all metals are good conductors of electricity but we consider silver to be the best conductor of all.
There's a Metal that Conducts Electricity But Not Heat
In science, there exists a law known as the Wiedemann-Franz Law that states, simply, that most metals that are good conductors of electricity are also good
Why is it that the least reactive metals are the best electrical...
One of the reasons why non reactive metals are good conductors is that they are good at staying as metals.
Metals are good conductors of electricity because - My cms
Question: Metals are good conductors of electricity because. Option: A. they contain free electrons B. the atoms are lightly packed C. they have high melting point D. All of the above.
Metals and its physical properties - Good conductors of heat.
Metals are good conductors of electricity because they contain free electrons. These free electrons can move easily through the metal and conduct electric current. Thus, electrical conductivity is another characteristic property of metals.
Conductors, What is a Conductor?, Examples of Conductors, List of...
In the solid state, some ionic solids with defects may conduct electricity to a small extent because the migration becomes possible due to the presence of vacancies or interstitial sites.
How is water a good conductor of electricity?
Water itself is not a conductor of electricity. In order for a substance to carry charge, two conditions must first be met
Metals make good conductors because the outer electrons of their atoms are loosely attached, and the electrons can drift through the metal when a voltage is applied. Some materials have all their electrons firmly fixed in place, so they do not conduct electricity well.
Option - Metallic
The properties of metals can be related to their structure and bonding (Topic 4). For instance, metals are good conductors of electricity because the delocalised electrons can move freely throughout the structure. Polymers.
Which Metals Conduct Electricity? - Metal Supermarkets UK...
While all metals can conduct electricity, certain metals are more commonly used due to being highly conductive.
BBC - GCSE Bitesize: Properties of metals
For example, copper is used for electrical wiring because it is a good conductor of electricity. Metal particles are held together by strong metallic bonds, which is why they have high melting and boiling points. The free electrons in metals can move through the metal...
Bizarre metal conducts electricity without heating up
Of all the metals found on Earth, most are both good conductors of heat and electricity. This is because classic physics dictates that their electrons are responsible for both the movement of electrical current and the transfer of heat.
Because of metallic bonds, metals a.are good conductors of...
Jenny and Mark complete a reactivity experiment by placing samples of metals into water. They initially place small shards of potassium into water and observe that hydrogen gas and potassium... Answer.
Introduction to Current Electricity
1. Compared to insulators, metals are better conductors of electricity because metals contain more free . 2. An electric current in a metal consists of moving . 3. As the temperature of a metallic conductor increases, its resistance usually .
Physicists Have Found a Metal That Conducts Electricity But Not Heat
The metal contradicts something called the Wiedemann-Franz Law, which basically states that good conductors of electricity will also be
Conductors and Insulators
Copper is still the most popular material used for wires because it is a very good conductor of electrical current and it is fairly inexpensive when compared to gold and silver. Aluminum and most other metals do not conduct electricity quite as good as copper.
do metallic compounds conduct electricity
Ionic compounds conduct electricity when dissolved in water because the movement of their negatively-charged and positively-charged
Information Technology in bussines - Why Are Metals Good...
Why Are Metals Good Conductors? Posted on April 4, 2018 by emma. Different metals are often employed for various applications because they are known for being good conductors of both heat and electricity.
Scientists discover metal that conducts electricity but not heat
26 (UPI) -- Researchers have discovered a metal that fails to comply with the Wiedemann-Franz Law, the rule that suggests good conductors of electricity will
Electrical conduction - Metals
Metals are good conductors of electricity and heat because they have unfilled space in the valence energy band. (The Fermi level dictates only partial occupancy of the band.)
Conductors and Insulators
Metals are good conductors (both of heat and electricity) because at least one electron per atom is free: i.e., it is not tied to any particular atom, but is, instead, able to move freely throughout the metal.
Which Materials are the Best Conductors?
Most metals are conductors; however, materials that prevent electricity from flowing are also important for circuits.
gary marketing - Why Are Metals Good Conductors?
Different metals are often employed for various applications because they are known for being good conductors of both heat and electricity.
Band Theory of Electrical Conductivity - Boundless Chemistry
Conductors. A conductor is a material that is able to conduct electricity with minimal impedance to the electrical flow. It is commonly a metal.
Use conductors in a sentence - conductors sentence examples
The neutralizing conductors for each disk are placed at right angles to each other. Compared with nonmetallic solids, they in general are good conductors of heat and of electricity. Clerk Maxwell demonstrated, however...
A Gases are not good conductors of electricity because of the...
Solid metals are good conductors of electricity, because electrons are allowed to move freely throughout the material. In the solid state, the atoms of metals are held in place and only vibrate.
Defects - Metals, Semiconductors, and Insulators
Silver and copper metal are among the best conductors of electricity, with a conductivity of only 106 ohm-cm. (This is why copper is the metal most often used in electric wires.)
Electricity, Conductors, and Insulators
Metals are good conductors of heat. Solids usually conduct heat better than liquids and gases. This is because the particles in solids are closer together.
Electrical engineering - conductivity of metals
Practical metals do not have a perfect lattice because of impurities and because of the deviation of atoms about their mean position due to lattice oscillations (Debye waves).
Chapter 1 Electricity
Many devices and machines are powered by electricity. All electrical phenomena result from the behavior. electric charge exist-positive and negative.
When Is Carbon an Electrical Conductor? - Popular Science
However, like a metal, graphite is a very good conductor of electricity due to the mobility of the electrons in its outer valence shells.
Electrical Safety Training for the Manufacturing Industry
The electricity that builds up when you scoot your feet on the floor on a cool, dry day and shock someone is also because of static electricity.
Crystal - Electric properties - Britannica.com
There are a few good conductors of the inexpensive copper ion that can be used as solid electrolytes in batteries.
Google Answers: Why certain metals are used in electronics
I believe silver is the better conductor of the two metals, but sometimes they seem to use gold instead of silver. Could this be because the electricity passes on the surface of the metal and silver's surface is more easily tarnished than that of gold which doesn't tarnish?
Electricity - steel = a strong metal that can be formed
Electricity can pass through some objects better than through others. Conductors are materials through which electrons can travel more freely. Copper, aluminium , steel and other metals are good conduc-tors.
Who discovered that lightning was a form of
Materials that conduct electricity do so because they allow the flow of negatively charged electrons. Those materials are called conductors.
3. Good conductor of electricity because some electrons from each atom are delocalized and can move freely throughout the crystal. Liquid metals also have delocalized electrons and, therefore, are good conductors of electricity.
A good conductor has low resistance to the ow of electric charges. Metals, like aluminum, gold, and copper, are good conductors.
Charges on Conductors
Because E 5 0 at all points within the conductor, the electric field at all points on the Gaussian surface must be zero.
The filament of an electric bulb is made up of tungsten metal because it has very high resistance and very high melting point.
Because the electric charge is confined to the object and is not moving, it is called an electrostatic charge. Thus static electricity is stationary electricity in the form of an electric charge at rest.
The electrons in a metallic element are free to move along all the atoms in the metal, and these materials are good electrical conductors.
Electrical Circuits - Lesson 6: Identifying Conductors and Insulators
This is because some conductors are more conductive than others, just as some insulators are better at blocking current than others.
OSHA Construction Glossary - Electrical Incidents - Contractor School...
Because electric current seeks to complete its circuit, it will travel along any path that is presented (path of least resistance), which is why
Министерство образования и науки
When the conductor moves parallel to the lines of force, no current is induced because no lines are cut.
Alkali metals. INTRODUCTION
Because the alkali metals are the elements which have the least ionization energy and the highest atomic radius, in each period they are a group of most active metals.
Read Physics Part 29 online for free at LightNovelOnl.com.
The best conductors for heat are metals. It is interesting to note that, as a rule good conductors of heat are also good conductors of electricity, while poor conductors of heat are also poor
BONDING. Chemical Bonds Bonds are forces that hold groups of...
Metals are good conductors of electricity because of this electron movement. Slide 9 Ionic Bonding Electrons are donated from a cation to an anion. Electrons lost are equal to electrons gained according to the octet rule. | <urn:uuid:41798826-7e55-4533-afe9-621ff7d1a8b5> | 3.375 | 3,204 | Content Listing | Science & Tech. | 34.863593 | 95,594,503 |
Satellites can help the EU monitor climate change, address international crises and contain natural disasters. Today in Brussels EU Research Commissioner Philippe Busquin and Mr Antonio Rodotà, the Director General of the European Space Agency (ESA), officially opened a large stakeholder consultation forum aiming at the definition of European needs to enhance global monitoring for environment and security (GMES).
250 participants, representing users, suppliers and researchers, addressed policy options to upgrade Europe`s capability for global monitoring by 2008. Combining spaceborne, land-based and airborne technologies, GMES will pool Europe`s activities in satellite observation and remote sensing. GMES seeks to make better use of Europe`s existing and planned capabilities and infrastructures and to develop mechanisms for improved collection and distribution of information.
Data from Envisat and other spaceborne and terrestrial observation systems will improve the ability of European researchers, private companies and public authorities to track environmental pollution, react to emergencies, improve cross-border response to catastrophic events, follow movements of refugees, facilitate the distribution of aid, and support peace-keeping troops outside Europe.
Commissioner Busquin said: "GMES is both a technological and an organisational challenge for Europe. It is a good example of how Europe, by working together in research, can develop technologies that contribute to improving the quality of life and meeting security needs. For instance, GMES will support implementation of the EU fisheries policy through more accurate monitoring of the evolution and migration of fish stocks."
Mr Rodotà referred to the dedicated efforts by ESA in the framework of GMES. As a new step, ESA will start implementing operational services than can now meet some priority users` requirements, based on current Earth observation capacities. "Concrete implementation of the GMES initiative is thus under way. Furthermore, ESA is now fully engaged with the European Commission in discussing the most appropriate arrangements for ensuring the long-term sustainability of the GMES initiative".
Today`s meeting is the first in a series that will foster dialogue between decision-makers and the many organisations involved in monitoring and in providing information for environmental and security purposes. The forum will lead to publication of a report at the end of 2003, to provide policy-makers with recommendations for future action.
GMES will enhance Europe`s ability to retrieve and process information obtained from space-borne and terrestrial observation systems with other geographical or socio-economic data. It will respond to growing concerns among policy-makers for timely, free and independent access to information on the environment and security at global, regional and local levels. GMES will support EU policies in areas such as sustainable development, global climate change and the common foreign and security policy.
At the global level, GMES will provide new verification tools to contribute to the precise monitoring of compliance with international agreements, such as the Kyoto protocol on climate change, as well as security and international aid agreements. At the same time, GMES will help local authorities pinpoint problems (e.g. shoreline erosion, environmental stress) and react more effectively to catastrophic events (e.g. floods, mudslides, avalanches, and forest fires). At EU level GMES will provide new objective data to support a broad range of EU policies, including regional development, transport, agriculture, enlargement, development, and foreign policy.
GMES is a key element of the European Space Strategy developed by the Commission and the European Space Agency. Along with the Galileo global satellite navigation system, GMES will be a major pillar of the European Space Policy emerging from the ever-closer partnership between the two organisations.
In November 2000, both the EU and ESA Ministerial Councils endorsed the GMES initiative and identified GMES and Galileo as top priorities and test cases for implementation of the European Strategy for Space.
GMES was also presented in the Commission Communication to the Gothenburg Council in June 2001, with the goal to create the system by 2008. The idea was further developed in the Communication "Outline GMES EU Action Plan (Initial Period: 2001-2003)", which elaborates on the objectives, general implementation principles, organisation and first priorities.
On the ESA side, GMES is at the core of a new 5-year programmatic element (the "GMES Services element"), fully subscribed by the ESA Council at ministerial level in November 2001. It will allow for the delivery of operational information, based on current European observation capacities, for the thematic priorities already identified in the GMES framework. A first invitation to tender for those services will be issued in September 2002.
GMES is also a key element of the "Aeronautics & Space" priority of the 6th EU Research Framework Programme and will feature in calls for proposals to be published at the end of 2002.
The GMES initiative will also be presented at the World Summit for Sustainable Development taking place in Johannesburg, South Africa, in September 2002, as a follow-up to the 1997 Kyoto conference on global climate change.
Michel Verbauwhede | AlphaGalileo
Global study of world's beaches shows threat to protected areas
19.07.2018 | NASA/Goddard Space Flight Center
NSF-supported researchers to present new results on hurricanes and other extreme events
19.07.2018 | National Science Foundation
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
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Many animals are covered in protective armor—shells, scales, plates, and frills that protect their soft bodies. But one group of little-known sea creatures called chitons have evolved armor that's unlike anything else in nature.
Because it contains eyes. Hundreds of eyes.
With lenses made from rock, that erode as the animals age and have to be continuously replaced.
Chitons are mollusks, related to snails, clams, and octopuses. Their oval bodies are covered by a hard shell consisting of eight overlapping plates, which makes them look a bit like a woodlouse with a skirt, or perhaps like the forehead of a Klingon. In many species, these plates are dotted with hundreds of tiny beads, each less than a tenth of a millimeter across. These are eyes. Each contains a lens, a light-sensitive retina, and a layer of black pigment.
Scientists have known about these eyes since the 19th century, but for most of that time, no one knew whether chitons could actually see out of them, or much about that anatomy. That all changed a few years ago, almost by accident.
Daniel Speiser, then a graduate student at the University of California, Santa Barbara, had dissected the lenses from the eyes of a West Indian fuzzy chiton, and dunked them into an acid bath to clean them. But lenses didn't become cleaner. They just disappeared.
Speiser soon discovered why. Unlike almost all other animal lenses, which are made from organic proteins that would have resisted the acid bath, chiton lenses are made from a mineral called aragonite. That's a form of calcium carbonate or limestone, which dissolves easily in acid. These animals peer at the world through lenses made of rock.
They can certainly detect light. When Speiser flashed shadows over idling chitons, the creatures would hunker down and flatten their armor against whatever they were resting upon. He also calculated that their eyes ought to be able to form images, although with a thousand times poorer resolution than human eyes. But why have hundreds of them? Is each one essentially its own pixel, like the facets of an insect's compound eye? Or does the animal combine the images from all its eyes into a single view of the world?
To find out, Speiser teamed up with Ling Li and Matthew Connors, two graduate students from the Massachusetts Institute of Technology. They placed a fuzzy chiton in an extremely powerful x-ray scanner to study the structure of its eyes.
The team found that the grains of aragonite in the lenses are much bigger than those in other parts of the chiton's armor, and strongly aligned. There's a reason for that. Every time light passes through the boundaries of different grains, it risks being scattered; by minimizing those boundaries, the chiton's lenses become better light-collectors.
Li and Connors tested their abilities by projecting objects through them to see if they genuinely can form images as Speiser had calculated. They can—blurry and heavily pixellated images, yes, but images nonetheless. Each eye could, for example, detect the shape of a 20-centimeter fish from a few meters away.
They could achieve higher resolutions if they weren't so very small. They can only pack so many light-sensitive cells beneath each lens, which limits the number of pixels in the image they can see. So, why do chitons have hundreds of tiny low-resolution eyes rather than just a few high-resolution ones—like us, or flies, or octopuses, or eagles, or jumping spiders?
The team suspects that the answer lies in the eyes' location—not on some obvious head, but actually embedded within the chiton's armor. They may help the animal to see threats, but they also compromise its defenses. Each eye consists of a large pear-shaped chamber beneath the lens, and these cavities, full of soft sensory tissues, create weaknesses in the chiton armour. The same aligned grains that help the lenses to collect more light also make them uniquely fragile. Li and Connors found that they collapse under forces that barely dent the rest of the plates.
If the eyes were any bigger, the chiton's shell would get even weaker. Their small size, Li thinks, represents a compromise between two different functions—vision and defense—that exist in the same suit of armor.
That explains why the eyes are small. But why so numerous? There are a few possibilities. Having aragonite lenses means that a chiton's eyes, unlike ours, will slowly erode with time. That's why it constantly replaces them much like a shark continuously grows new teeth; and perhaps having hundreds of eyes provides even more back-ups. They also allow the animal to detect threats coming from many different directions, which is important because the eyes can't move and chitons take several minutes to turn around.
But Sonke Johnsen from Duke University, who was Speiser's graduate advisor, is still perplexed at how good the chiton's eyes are. “They're forming decent images in an animal that, to be really blunt, is not that smart,” he says. “A chiton doesn't have many ... behavioral outputs. It can wander around, graze, and glue down onto a rock. That's about it. Why something that only really needs to tell if a predator is round is building all these really beautiful crystal lenses, and paying the price of making their armor not as strong, is a really good question.”
“It goes against the general paradigm that the world is divided into dumb animals without heads and not a lot of sensory capabilities, and smart animals with heads that move around and have sharp sense,” he adds. “There are all these animals that don't fit these categories. They open our eyes up to new ways of solving the same problems.”
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A numerical method is developed for estimating the acoustic power of any baffled planar structure, which is vibrating with arbitrary surface velocity profile. It is well known that this parameter may be calculated with good accuracy using near field data, in terms of an impedance matrix, which is generated by the discretization of the vibrating surface into a number of elementary radiators. Thus, the sound pressure field on the structure surface can be determined by a combination of the matrix and the volume velocity vector. Then, the sound power can be estimated through integration of the acoustic intensity over a closed surface. On the other hand, few works exist in which the calculation is done in the far field from near field data by the use of radiation matrices, possibly because the numerical integration becomes complicated and expensive due to large variations of directivity of the source. In this work a different approach is used, based in the so-called Propagating Matrix, which is useful for calculating the sound pressure of an arbitrary number of points into free space, and it can be employed to estimate the sound power by integrating over a finite number of pressure points over a hemispherical surface surrounding the vibrating structure. Through numerical analysis, the advantages/disadvantages of the current method are investigated, when compared with numerical methods based on near field data. A flexible rectangular baffled panel is considered, where the normal velocity profile is previously calculated using a commercial finite element software. However, the method can easily be extended to any arbitrary shape. Good results are obtained in the low frequency range showing high computational performance of the method. Moreover, strategies are proposed to improve the performance of the method in terms of both computational cost and speed.
1. Arenas J.P., Ramis J., Alba J. (2010), Estimation of the sound pressure field of a baffled uniform elliptically shaped transducer, Appl. Acoust., 71, 128-133.
2. Atalla N., Nicolas J. (1994), A new tool for predicting rapidly and rigorously the radiation efficiency of plate-like structures, J. Acoust. Soc. Am., 95, 3369-
3. Bai M.R., Tsao M. (2002), Estimation of sound power of baffled planar sources using radiation matrices, J. Acoust. Soc. Am., 112, 876-883.
4. Baumann W.T., Ho F.-S., Robertshaw H.H. (1992), Active structural acoustic control of broadband disturbances, J. Acoust. Soc. Am., 92, 1998-2005.
5. Berkhoff A.P. (2002), Broadband radiation modes: Estimation and active control, J. Acoust. Soc. Am., 111, 1295-1305.
6. Berry A. (1991), Vibration and acoustic radiation of planar structures, complex immersed in a light fluid or in a heavy fluid, [in French: Vibrations et rayonnement acoustique de structures planes, complexes immergées dans un fluide léger ou dans un fluide lourd], Université de Sherbrooke, Ph.D. Thesis.
7. Borgiotti G.V. (1990), The power radiated by a vibrating body in an acoustic fluid and its determination from boundary measurements, J. Acoust. Soc. Am., 88, 1884-1893.
8. Borgiotti G.V., Jones K.E. (1994), Frequency independence property of radiation spatial filters, J. Acoust. Soc. Am., 96, 3516-3524.
9. Cremer L., Heckl M., Ungar E.E. (1988), Structure-Borne Sound, Springer-Verlag, Berlin.
10. Cunefare K.A., Koopmann G.H. (1991), Global optimum active noise control: Surface and far-field effects, J. Acoust. Soc. Am., 90, 365-373.
11. Elliot S.J., Johnson M.E. (1993), Radiation modes and the active control of sound power, J. Acoust. Soc. Am., 94, 2194-2204.
12. Fahy F.J., Gardonio P. (2007), Sound and Structural Vibration, Academic Press, Oxford.
13. Fan X., Moros E., Straube W.L. (1997), Acoustic field prediction for a single planar continuouswave source using an equivalent phased array method, J. Acoust. Soc. Am., 102, 2734-2741.
14. Fiates F. (2003), Sound radiation of beam-reinforced plates, [in Portuguese: Radicao sonora de placas refocadas por vigas], Universidade Federal de Santa Catarina, Ph.D. Thesis.
15. Fisher J.M., Blotter J.D., Somerfeldt S.D., Gee K.L. (2012), Development of a pseudo-uniform structural quantity for use in active structural acoustic control of simply supported plates: An analytical comparison, J. Acoust. Soc. Am., 131, 3833-3840.
16. ISO-3745 (2003), Acoustics - Determination of sound power levels of noise sources - Precision methods for anechoic and semi-anechoic rooms, Geneva, Switzerland: ISO.
17. Langley R.S. (2007), Numerical evaluation of the acoustic radiation from planar structures with general baffle conditions using wavelets, J. Acoust. Soc. Am., 121, 766-777.
18. Li W.L. (2006), Vibroacoustic analysis of rectangular plates with elastic rotational edge restraints, J. Acoust. Soc. Am., 120, 769-779.
19. Maidanik G. (1962), Response of Ribbed Panels to Reverberant Acoustic Fields, J. Acoust. Soc. Am., 34, 809-826.
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21. Naghshineh K., Koopmann G.H., Belegundu A.D. (1992), Material tailoring of structures to achieve a minimum radiation condition, J. Acoust. Soc. Am., 92, 841-855.
22. Naghshineh K., Koopmann G.H. (1993), Active control of sound power using acoustic basis functions as surface velocity filters, J. Acoust. Soc. Am., 93, 2740-
23. Pàmies T., Romeu J., Genescà M., Balastegui A. (2011), Sound radiation from an aperture in a rectangular enclosure under low modal conditions, J. Acoust. Soc. Am., 130, 239-248.
24. Rayleigh L. (1896), The Theory of Sound, Dover, 130, New York.
25. Sandman B.E. (1977), Fluid-loaded vibration of an elastic plate carrying a concentrated mass, J. Acoust. Soc. Am., 61, 1503-1510.
26. Wallace C.E. (1972), Radiation resistance of a rectangular panel, J. Acoust. Soc. Am., 51, 946-952.
27. Williams E.G., Maynard J.D. (1982), Numerical evaluation of the Rayleigh integral for planar radiators using the FFT, J. Acoust. Soc. Am., 72, 2020-2030.
28. Zou D., Crocker M.J. (2009), Sound Power Radiated from Rectangular Plates, Arch. Acoust., 34, 1, 25-39. | <urn:uuid:96baccac-4128-40ab-bff7-3ebf6f944851> | 2.546875 | 1,662 | Academic Writing | Science & Tech. | 70.021775 | 95,594,572 |
A waste with a concentration of 0.1 gram per liter is to be introduced to a hazardous waste reactor that is to achieve 90% destruction. A reactant, which is intended to cause an exothermic reaction is to be mixed with the waste stream so that there is only one common/mixed input to the reactor.
If the waste is in excess of the reactant and is modeled with 1st order kinetics equal to k=1000/minute --- what does this mean?
And if the reactant was in excess to the waste stream and was modeled with 2nd order kinetics equal to k = 1000 g-moles per liter minute --- what does this mean?
What is the simple difference between the first and second order kinetics? Is there a benefit to one process over the other?© BrainMass Inc. brainmass.com July 17, 2018, 10:02 am ad1c9bdddf
Let W be the concentration of the waste
R be the concentration of the reactant
P be the product
We can write the general reaction as below:
W + R = P
Here we're not given the reaction stoichiometry, i.e. how much W will react with how much R. Therefore it is normal in chemistry that a number of assumptions and predictions are made.
First, the waste is in excess of the reactant and is modeled with 1st order ...
The solution provides detailed explanations and instructions for the problem. | <urn:uuid:4001d3ec-3c34-4e75-93ff-ee5275d26e54> | 3.46875 | 303 | Q&A Forum | Science & Tech. | 70.663824 | 95,594,599 |
Holocene activity evidence on the southeast boundary fault of Heqing basin, middle segment of Heqing-Eryuan fault zone, West Yunnan Province, China
The Heqing-Eryuan fault is an important part of the active fault system in the Northwestern Yunnan Province, China. Thus, the study on the nature, characteristics and activity history of this fault can provide not only the basis for seismic safety and engineering evaluation, but also the important information for the characteristics, history and patterns of the structural deformation of the southeastern margin of the Tibetan Plateau. Trench and faulted landforms investigations could provide effective paleoseismic methods to obtain the recent parameters of active faults. Using these methods, this study makes some breakthroughs on the recent activity of southeast boundary fault of the Heqing basin, middle segment of Heqing-Eryuan fault zone. Results indicate that the average vertical slip rate and left-lateral slip rate of the segment are about 0.28 mm/a and 1.80 mm/a respectively since the Late Pleistocene. The trench near the Beixi Village at the southeast boundary fault of the Heqing basin reveals that there have been at least three paleoearthquake events during the Holocene (~8 ka BP). The vertical displacement and sinistral strike-slip distance of a single paleoearthquake are ~20 cm and ~1.2 m, respectively. The estimated paleoearthquake magnitudes with Ms7.0, and the recurrence interval at 2-5 ka, as well as the latest activity time during 800- 290 cal yr BP, are of great significance for preventing and mitigating regional earthquake disasters.
KeywordsHeqing-Eryuan fault zone Paleoearthquake Holocene activity Sinistral strikeslip Heqing basin
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We thank Profs. XU Xi-wei, RAN Yong-kong, ZHANG Shi-min, TIAN Qin-jian and CHANG Zufeng for assistance in field investigation and Dr. ZHAO Jun-xiang for OSL dating. We are grateful to the staffs of Earthquake Bureau of Heqing County, Yunnan Province, China for the trench excavation and the Earthquake Administration of Yunnan Province, China for the airphoto collection. We also thank Prof. HUANG Zhong-xian for improving the English writing and two anonymous reviewers for valuable comments, which helped to improve this manuscript. This work was supported by the National Natural Science Foundation of China (Grant No. 41171001, 41471002, 41402184), the 1:50000 Active Fault Mapping of Heqing- Eryuan fault (Grant No. 201108001-20) and a research grant from the Institute of Crustal Dynamics, China Earthquake Administration (Grant No. ZDJ2013-17).
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The research will help predict how migration of animals or changes to their habitats associated with climate change could impact on the evolution of relationships between predators and their prey.
Scientists have shed light on how species and their natural enemies chase each other across continents in a game of cat and mouse lasting for millions of years. They used a technique known as population genetics to reveal historical information hidden in the DNA of small plant-feeding insects and their wasp enemies, and to show how closely predators track their prey over long periods of time.
The study, involving University of Edinburgh scientists, reconstructed the evolutionary arms race between the insects and their wasp enemies. The study looked at 31 species, all of which originated in Iran and Turkey, and spread into Europe over the past four million years. The timing of each species' journey was determined by how well it coped with the many ice ages during this period of the Earth's history.
Researchers found that during these natural cycles of climate change, the plant-feeding insects often outran their predators, moving faster and so escaping attack – often for hundreds of thousands of years. Battles between predators and prey were sometimes interrupted for long periods of time, suspending the arms race between the two groups.
Scientists say relationships between species that evolve closely together can be fragile, leading to biological communities that can be easily disrupted by climate change. However, this research suggests that, at least for these insects, the predator-prey relationships are less fragile and are resistant to disruption. In addition, however, modern environments are much more fragmented than those in the past, making all natural communities more sensitive to change.
The study, carried out in collaboration with the UK Centre for Ecology and Hydrology and the City University New York, was published in Current Biology and supported by the Natural Environment Research Council.
Professor Graham Stone of the University of Edinburgh's School of Biological Sciences, who led the study, said: "Insects account for more than half of all animal species found on Earth. Interactions between insects, and between insects and other kinds of organism, fulfil many important biological roles – including crop pollination and pest control. We hope that our study will improve understanding of how interactions between modern species may respond to climate change."
Catriona Kelly | EurekAlert!
World’s Largest Study on Allergic Rhinitis Reveals new Risk Genes
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For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
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