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78,653,446 | https://en.wikipedia.org/wiki/HIP%2067522 | HIP 67522 is a G-class star which, by comparison with the Sun, is slightly larger (1.38 ) and cooler (5675 K versus 5772 K for the Sun). It lies about 127 parsecs away in the constellation Centaurus. Its visual magnitude of 9.8 makes it much too faint to be seen by the unaided eye.
Two exoplanets, HIP 67522 b and HIP 67522 c, are known to orbit the star and transit its face as seen from Earth. Their orbital periods are much less than Mercury's 88 days around the Sun, being 6.96 days for b and 14.33 days for c.
References
Centaurus
G-type main-sequence stars
Hypothetical planetary systems
067522
120411
Durchmusterung objects | HIP 67522 | [
"Astronomy"
] | 168 | [
"Centaurus",
"Constellations"
] |
78,653,449 | https://en.wikipedia.org/wiki/Carballeira%20de%20San%20Xusto | The Carballeira de San Xusto is an oak forest located in the parish of San Xurxo de Sacos (Cerdedo-Cotobade), on a hill above the Lérez River, near the Ria de Pontevedra, in Galicia, Spain.
Characteristics
It is a traditional gathering place and a reference for legends and old tales; it contains centuries-old oak trees as well as chestnut and American oak trees. Once extensive in area, it has now greatly diminished.
Between 1990 and 1996, there was a dispute over the ownership of the carballeira between the parishioners of San Xurxo de Sacos and the Archdiocese of Santiago de Compostela. On June 6, 1990, the parish priest Manuel Lorenzo registered in Ponte Caldelas the ownership of this space and the mountain of Lixó on behalf of the Church. After various acts of protest and years of confrontation, the Provincial Court and the Supreme Court upheld the resolution issued by a preliminary court that sided with the parishioners. The ownership of the carballeira belongs to the Community of Montes of the parish.
During the wildfire wave of 2006 in Galicia, a strong fire descended from Cerdedo to Pontevedra along the banks of the Lérez River, passing near the carballeira on August 5. The villagers celebrating the pilgrimage had to leave in haste, either to escape the fire or to help extinguish it. Ultimately, the carballeira was saved. In gratitude, a devotee of Saints Xusto and Pastor brought popular singers to the festivities in subsequent years, such as Manolo Escobar, Bertín Osborne, or David Bustamante, attracting thousands of people to the carballeira.
Architectural heritage
It is presided over by a cruceiro and a chapel, where the pilgrimage of Saints Xusto and Pastor is celebrated on August 5 and 6. In the past, the sword dance was performed in the carballeira, and the local youths hunted wild goats by descending the cliffs of the valley. The community and pilgrims participated in the saint's procession through the parish, which included images of various saints as well as the banner of the Agricultural Society of San Xurxo de Sacos, founded in 1903. Some pilgrims came with offerings, bringing coffins and offerings to be bid upon.
The small chapel preserves the covered presbytery, from the 15th or 16th century, with a ribbed vault. The nave dates from the 18th century. Above the main door, there is a stone with the following inscription in Spanish (pictured):
Above a door on the southern-side wall, there is another stone with the following inscription in Spanish (pictured):
In June 2007, a statue commemorating the community's struggle was inaugurated, conceived by the sculptor Alfonso Vilar and completed by students of the Escola de Canteiros de Poio. The sculpture includes the following inscription:
Gallery
References
Forests | Carballeira de San Xusto | [
"Biology"
] | 603 | [
"Forests",
"Ecosystems"
] |
78,653,518 | https://en.wikipedia.org/wiki/Ilunocitinib | Ilunocitinib, sold under the brand name Zenrelia, is a veterinary medication used for the treatment of pruritus (itching) in dogs. It is a non-selective janus kinase inhibitor.
Ilunocitinib was approved for medical use in the United States in September 2024, and in Canada in December 2024.
Medical uses
Ilunocitinib is indicated for the control of pruritus associated with allergic dermatitis and control of atopic dermatitis in dogs at least twelve months of age.
Contraindications
It is not safe to administer vaccines to dogs that are concurrently receiving ilunocitinib.
Society and culture
Legal status
Ilunocitinib was approved for medical use in the United States in September 2024, and in Canada in December 2024.
Names
Ilunocitinib is the international nonproprietary name.
Ilunocitinib is sold under the brand name Zenrelia.
References
Dog medications
Immunosuppressants
Janus kinase inhibitors
Azetidines
Cyclopropanes
Nitriles
Pyrazoles
Pyrrolopyrimidines
Sulfonamides | Ilunocitinib | [
"Chemistry"
] | 241 | [
"Nitriles",
"Functional groups"
] |
78,657,802 | https://en.wikipedia.org/wiki/PKS%200528%2B134 | PKS 0528+134 is a distant blazar located in the Galactic anticenter towards the constellation of Orion. This is a compact radio quasar, classified as radio-loud with a redshift of (z) 2.07 yet having low polarization. It was first discovered in 1977 by astronomers as a radio source and contains a radio spectrum that appears as flat making it a flat-spectrum radio quasar. It has an optical brightness of 19.5.
Description
PKS 0528+134 is found variable on the electromagnetic spectrum and a source of high energy gamma rays. It showed long-term variability on time scales at high radio frequencies. Between 1981 and 1982, PKS 0528+134 exhibited a drop in its 4.8, 8.0 and 14.5 GHz flux value by about 4-5 Jansky (Jy), with a lowest recorded flux of 1.5 Jy in 1990. A drastic increase in gamma ray emission was detected in PKS 0528+134 beginning 1991. That same year, it showed a nonthermal outburst suggesting a period of relativistic plasma being ejected. PKS 0528+134 also had two radio millimeter outbursts.
Between the months of July and December 2009, PKS 0528+134 reached a state of quiescence. When observed by astronomers, they found no traces of either significant flux or spectral variability in most radio bands although flux variability was discovered in optical regime, followed by a weak pattern of spectral softening. This suggests the accretion disk of PKS 0528+134 might play a role at the optical spectrum's blue end. Optical spectropolarimetry also suggests PKS 0528+134 has an extreme degree of polarization, indicating possibility of synchrotron radiation providing emission at the optical spectrum's red end.
Radio images made by the Very Long Baseline Interferometry at 22 GHz shows radio structure of PKS 0528+134 as a 5 mas extended one-sided jet with a more diffused northwest component at a position angle of 50° and two other components located in the west direction of various distances. At 43 GHz, the structure is further resolved into five components showing superluminal motions reaching high as 23 h−1 with increasing motions per distance from the core. An inverted core spectrum is also discovered. Very Long Baseline Array finds three of its components shows progressive acceleration with a strongly polarized northern knot feature. A new component is also found at higher frequencies.
The supermassive black hole mass of PKS 0528+134 is estimated to be 85 x 108 Mʘ based on an equation calculation integrated between the values of 3 and 30 MeV via flux measurements made by the Imaging Compton Telescope. A luminosity value of 4.1 x 1049 ergs has also been calculated for the object as well.
References
External links
PKS 0528+134 on SIMBAD
PKS 0528+134 on NASA/IPAC Extragalactic Database
Blazars
Quasars
Active galaxies
Astronomical objects discovered in 1977
2824388
Orion (constellation) | PKS 0528+134 | [
"Astronomy"
] | 631 | [
"Constellations",
"Orion (constellation)"
] |
78,663,164 | https://en.wikipedia.org/wiki/KPNO-Tau%2012 | KPNO-Tau 12 (also called 2MASS J0419012+280248) is a low-mass brown dwarf or free-floating planetary-mass object that is surrounded by a protoplanetary disk, actively accreting material from it.
Discovery
KPNO-Tau 12 was identified in 2003 in data from a survey of the Taurus Molecular Clouds taken with a telescope at the Kitt Peak National Observatory (KPNO) and 2MASS. The object was observed with the MMT Observatory/Blue Channel spectrometer and with Keck/LRIS. KPNO-Tau 12 showed a spectral type of M9 and also showed strong Hydrogen-alpha emission. At the time its mass was estimated to be around 0.02 (or 21 ), which would make it a brown dwarf. Since then several works found that it likely has a mass near or below the deuterium-burning limit, which makes this object a low-mass brown dwarf or planetary-mass object (e.g. 14.6 , 13.6 , 6-7 , 16.5 , , ).
A few other free-floating planetary-mass objects are known in the Taurus Clouds. These include three other objects with possible disks around them.
Atmosphere
Observations with Keck/LRIS showed several absorption features. These are titanium oxide, calcium hydride, vanadium oxide, sodium and potassium. A spectrum with Keck/NIRSPEC was interpreted to be consistent with very low gravity. This is typical for young sources. Several re-classifications of the spectral type were made over the years. In 2013 it was re-classified as a M9.25. In 2018 it was re-classified as a L0.7, which could make this object an early L-dwarf. A spectrum observed with VLT/SINFONI was published in 2022, estimating a spectral type of M9.8.
Protoplanetary disk
KPNO-Tau 12 showed strongest H-alpha emission in both the MMT and Keck optical spectra. It also showed helium (He I) and calcium (Ca II IR triplet) emission in the Keck spectrum, which are usually seen in stars that undergo intense accretion of material from a surrounding protoplanetary disk. Additionally a Keck infrared spectrum shows a prominent emission line (see figure 10 of their work), which is described as Paschen β at 1.28 μm in the appendix of the paper. Paschen lines can be used as additional accretion indicators. In 2010 two works used observations with the Spitzer Space Telescope. These two works first identified infrared excess around KPNO-Tau 12 and classified it as a class II disk. A class II disk is composed of both a gaseous and a dusty part and belongs to the protoplanetary disks. Observation with the Spitzer Infrared Spectrograph showed that the silicate emission feature is likely missing. The dust mass of the disk was estimated to be or , depending on the work. The total (gas+dust) mass was estimated to be or , depending on the work. The dust temperature was estimated to be Kelvin and the dust grains are smaller than 27.5 millimeters.
See also
Other free-floating planetary-mass objects with disks:
2MASS J11151597+1937266, closest free-floating planetary-mass object surrounded by a disk
Cha 110913−773444
OTS 44, has a well-studied disk
J1407b, could also orbit a star
Other planetary-mass objects with disks that bound to a star:
SR 12c
Delorme 1 (AB)b
2M1207b
PDS 70c, first circumplanetary disk
References
Rogue planets
M-type brown dwarfs
Taurus (constellation)
Astronomical objects discovered in 2003
Circumstellar disks | KPNO-Tau 12 | [
"Astronomy"
] | 799 | [
"Taurus (constellation)",
"Constellations"
] |
78,663,925 | https://en.wikipedia.org/wiki/The%20Feiner%20Points%20of%20Leadership | The Feiner Points of Leadership: The 50 Basic Laws That Will Make People Want to Perform Better for You, first published in 2004, is the book written by Michael Feiner, the former Vice President and Chief People Officer at Pepsi-Cola and former professor of Columbia Graduate School of Business. It presents 50 laws for managing business problems based on the author's experiences. The book explores how leaders can positively influence their teams, foster collaboration, and build a productive, motivated work environment. Feiner's approach is based on the idea that leadership is not just about managing tasks but about inspiring and empowering others to achieve their best potential.
It was selected by the Toronto Globe and Mail as the Best Business Book of 2004.
References
2004 non-fiction books
Management books
Business books
Personal development | The Feiner Points of Leadership | [
"Biology"
] | 159 | [
"Personal development",
"Behavior",
"Human behavior"
] |
78,668,010 | https://en.wikipedia.org/wiki/Single%20pilot%20operations | In aviation, Single Pilot Operations (SPO) refers to a proposal for commercial flights operated with one pilot, where previously two would be required.
Single pilot operations will require improvements in technology including aircraft and cockpit design, and changes to pilot training. Safety must be proved to win acceptance by regulators and the public.
History
Historically, large aircraft required several personnel on the flight deck, such as a navigator, a flight engineer, and a dedicated radio operator. Improvements in automation, reliability and technology such as autopilot and satellite navigation have enabled modern large aircraft to operate safely with only two pilots on duty.
With further technological improvements, it may be possible safely to reduce crew requirements to one, providing cost savings.
The European Union Aviation Safety Agency (EASA) has been investigating Extended Minimum Crew Operations (eMCO), where an aircraft could be operated by one pilot in the cruise. This would be an initial requirement before single pilot operations might be allowed at a later stage. The research project runs from 2022 to 2025. Airbus and Dassault have expressed interest in eMCO.
Airbus completed its Autonomous Taxi, Take-Off and Landing (ATTOL) project in 2020, demonstrating an autonomous flight with an A350-1000 aircraft. In 2023, Airbus project Dragonfly used a combination of normal and infrared cameras, as well as radar, to assist pilots in various situations. In 2024 Airbus began testing an autonomous aircraft taxi system called "Optimate".
Opposition
Proposals for Single Pilot Operations are opposed by several pilots' trade unions, including the International Federation of Air Line Pilots' Associations (IFALPA), the American Air Line Pilots Association (ALPA), the European Cockpit Association, and the British Air Line Pilots Association.
In their white paper, ALPA argue that two-pilot operations reduces errors through cross-checking, workload sharing and better decision-making, and provides redundancy in the case of pilot incapacitation. They argue that pilots learn from each other when working together; that pilots are more versatile than aircraft equipment and sensors; and that pilots are better at autonomous decision making. They also raise concerns about cybersecurity.
See also
Automated flight attending
Autonomous aircraft
Germanwings Flight 9525
Single-pilot resource management
Uninterruptible autopilot
References
External links
Airbus – Autonomous Flight
One Means None, European Cockpit Association campaign website
Aircraft automation | Single pilot operations | [
"Engineering"
] | 484 | [
"Automation",
"Aircraft automation"
] |
78,668,488 | https://en.wikipedia.org/wiki/NGC%204632 | NGC4632 is a spiral galaxy in the constellation of Virgo. Its velocity with respect to the cosmic microwave background for is , which corresponds to a Hubble distance of . However, 15 non-redshift measurements give a much closer distance of . It was discovered by German-British astronomer William Herschel on 22 February 1784.
Polar Ringed Galaxy
It was discovered in 2023 that the galaxies NGC 4632 and NGC 6156 are surrounded by a disk of cold hydrogen orbiting 90 degrees around their disks. These are the very first polar-ringed galaxies discovered through radio wave observations. These observations were made as part of the WALLABY astronomical survey.
NGC 4666 Group
According to A. M. Garcia, NGC 4632 is a member of the NGC 4666 galaxy group (also known as LGG 299). This group has 3 members, including NGC 4666 and NGC 4668.
Supernova
One supernova has been observed in NGC 4632:
SN1946B (typeII, mag. 15.7) was discovered by Edwin Hubble in May, 1946.
See also
List of NGC objects (4001–5000)
References
External links
4632
042689
07870
+00-32-038
12399+0011
Virgo (constellation)
17840222
Discoveries by William Herschel
Spiral galaxies | NGC 4632 | [
"Astronomy"
] | 275 | [
"Virgo (constellation)",
"Constellations"
] |
78,671,395 | https://en.wikipedia.org/wiki/Heptyl%20butyrate | Heptyl butyrate is an ester that is naturally occurring in fresh apples, plums, and babaco fruits. It is the condensation product of heptyl alcohol and butyric acid. It is available commercially for use as bait in traps yellowjackets and wasps and is specific for these types of pests rather than honeybees and other beneficial insects. It is considered a "safe, food-grade compound" by the United States Environmental Protection Agency.
References
Heptyl esters
Butyrate esters
Plant products | Heptyl butyrate | [
"Chemistry"
] | 113 | [
"Natural products",
"Organic compounds",
"Plant products",
"Organic compound stubs",
"Organic chemistry stubs"
] |
78,680,505 | https://en.wikipedia.org/wiki/NGC%201162 | NGC 1162 is a lenticular galaxy located in the constellation Perseus. It was discovered by astronomer William Herschel on October 14, 1784. The galaxy lies approximately 200 million light-years away from Earth and is classified as a type SA0^−^ galaxy, indicating a smooth structure with little to no spiral features.
Discovery
NGC 1162 was discovered by William Herschel on October 14, 1784, during his extensive sky surveys. It is included in the New General Catalogue compiled by astronomer John Louis Emil Dreyer. The galaxy was cataloged based on observations made with Herschel's 18.7-inch reflecting telescope.
Physical characteristics
NGC 1162 is a lenticular galaxy, denoted as SA0^−^ in the Hubble sequence. Lenticular galaxies are considered intermediate types between spiral and elliptical galaxies. NGC 1162 lacks prominent spiral arms and has a smooth, featureless disk with a central bulge. It spans an apparent size of approximately 1.5 by 1.0 arcminutes in the sky and has an apparent magnitude of 13.1, making it faint but observable with mid-sized telescopes.
The galaxy is estimated to be around 200 million light-years away, as determined by its redshift value (z = 0.01475).
Location and observation
NGC 1162 is situated in the northern constellation of Perseus. It can be located using star maps and is best observed in the winter months from the Northern Hemisphere. The galaxy appears faint and requires dark skies and telescopes with moderate aperture for clear observation.
Environment and group association
NGC 1162 is part of a galaxy group within the Perseus constellation. Galaxy groups are smaller collections of galaxies bound together by gravitational forces. The interaction with neighboring galaxies may influence its structure and star formation history. However, lenticular galaxies like NGC 1162 typically have low levels of star formation.
Importance in astronomy
NGC 1162 serves as a valuable object for studying galaxy morphology and the transition between spiral and elliptical galaxies. Its relatively close distance allows astronomers to analyze its structure, stellar populations, and dynamics in detail.
Recent studies have focused on its inactive galactic nucleus and the presence of older stellar populations, indicating a decline in star formation activity over time.
References
External links
NASA/IPAC Extragalactic Database (NED) – NGC 1162
Sloan Digital Sky Survey – NGC 1162
Galaxy Zoo – Public Galaxy Data
NGC objects
Perseus (constellation)
Lenticular galaxies
Astronomical objects discovered in 1784
Intermediate spiral galaxies
Galaxies
Barred lenticular galaxies
Discoveries by William Herschel | NGC 1162 | [
"Astronomy"
] | 511 | [
"Perseus (constellation)",
"Constellations"
] |
78,680,855 | https://en.wikipedia.org/wiki/NGC%201163 | NGC 1163 is a barred spiral galaxy located in the constellation Perseus. It is situated approximately 205 million light-years away from Earth and has an apparent magnitude of 13.5. The galaxy was discovered by the German-British astronomer William Herschel on October 14, 1784.
Discovery
NGC 1163 was first observed by William Herschel on October 14, 1784, using his 18.7-inch reflecting telescope. The galaxy was later cataloged in the New General Catalogue (NGC) by John Louis Emil Dreyer. Its precise celestial coordinates place it in the Perseus constellation, making it a target for amateur and professional astronomers alike.
Physical characteristics
NGC 1163 is classified as a barred spiral galaxy (SBc type) under the Hubble Sequence. The prominent bar structure at its center channels gas and dust toward the galaxy’s nucleus, fueling star formation. Its spiral arms are moderately tightly wound and exhibit regions of active star formation.
The galaxy spans an apparent size of about 1.2 by 0.9 arcminutes and shines with an apparent magnitude of 13.5, making it observable with mid-sized telescopes under dark-sky conditions.
Location and observation
NGC 1163 is located in the constellation Perseus, which is best observed during winter in the Northern Hemisphere. The galaxy lies roughly 205 million light-years from Earth, as determined by its redshift (z = 0.0151). Amateur astronomers can observe NGC 1163 with mid-to-large aperture telescopes, and long-exposure astrophotography can reveal its bar structure and faint spiral arms.
Environment and galaxy group
NGC 1163 is part of a loose galaxy group in the Perseus constellation. It interacts gravitationally with neighboring galaxies, which may have influenced its structure and bar formation. These gravitational interactions are thought to play a key role in redistributing gas and triggering star formation in the galaxy's arms.
Scientific importance
NGC 1163 is of interest to astronomers studying barred spiral galaxies and their star formation dynamics. The bar structure acts as a mechanism for funneling material toward the galactic core, potentially fueling an active galactic nucleus (AGN). However, current observations suggest a relatively low AGN activity in NGC 1163.
Research into NGC 1163 also contributes to the broader understanding of galaxy evolution and the role of bars in galaxy morphology.
References
External links
NASA/IPAC Extragalactic Database (NED) – NGC 1163
Sloan Digital Sky Survey – NGC 1163
Galaxy Zoo – Public Galaxy Data
NGC objects
Astronomical objects discovered in 1784
Discoveries by William Herschel | NGC 1163 | [
"Astronomy"
] | 526 | [
"Perseus (constellation)",
"Constellations"
] |
77,287,285 | https://en.wikipedia.org/wiki/Paramantoida | Paramantoida amazonica is a species of praying mantis from South America. It is the only species in the genus Paramantoida.
References
Mantoididae
Biota of Brazil
Taxa described in 2014 | Paramantoida | [
"Biology"
] | 45 | [
"Biota by country",
"Biota of Brazil"
] |
77,287,294 | https://en.wikipedia.org/wiki/Vandamm%20House | The Vandamm House is a setting in the Hitchcock movie North by Northwest. Its modern architecture was inspired by the real house Fallingwater which was designed by Frank Lloyd Wright. In the movie, the Vandamm House is located near Mount Rushmore but it was not actually built. The interiors were shot on a set constructed in an MGM studio in Culver City by Robert F. Boyle while the exterior shots used a matte painting.
References
Fictional houses | Vandamm House | [
"Engineering"
] | 93 | [
"Architecture stubs",
"Architecture"
] |
77,289,309 | https://en.wikipedia.org/wiki/Calibrator%20star | A calibrator star is a star that is typically used tor calibration purposes on high-sensitized sensors located on space telescopes.
Calibrator stars do not usually follow a specific criteria, but are normally hand-picked for different reasons.
Definition
Infrared and optically bright stars may be observed for calibration purposes by satellites, particularly those with sensitivity to both infrared and visible radiation. The stars chosen generally meet the following criteria: they have a visual manitude that is eual to or less than +6, and an IR brightness (in the 1-5 micrometer range) greater than that of Vega.
The stars are strictly southern objects (i.e., their declinations are negative), and most are cool stars of spectral classes K and M. While these are not the only stars that might serve for these purposes, they are well distributed across the southern sky and some should be visible at all times.
List
Catalog
A catalog of recommended calibrator stars does exist, with 1,510 stars being listed. The catalog gives the magnitude, mass and other statistics.
See also
Lists of stars
First light (astronomy)
References
Stars
Astronomical spectroscopy
Astrometry
Space telescopes | Calibrator star | [
"Physics",
"Chemistry",
"Astronomy"
] | 242 | [
"Spectrum (physical sciences)",
"Stars",
"Astrometry",
"Astrophysics",
"Spectroscopy",
"Space telescopes",
"Astronomical spectroscopy",
"Astronomical objects",
"Astronomical sub-disciplines"
] |
77,289,418 | https://en.wikipedia.org/wiki/NGC%205455 | NGC 5455 is an emission nebula (HII region) located in Messier 101 (the Pinwheel Galaxy) towards the constellation Ursa Major. Eight other regions of Messier 101 are listed in the New General Catalogue, namely NGC 5447, NGC 5449, NGC 5450, NGC 5451, NGC 5453, NGC 5458, NGC 5461 and NGC 5462. Three of these regions were discovered by William Herschel (NGC 5447, NGC 5461 and NGC 5462) and the other six by Bindon Stoney.
See also
List of NGC objects (5001–6000)
Lists of nebulae
External links
NGC 5455 at NASA/IPAC
NGC 5455 at SIMBAD
NGC 5455 at LEDA
References
Emission nebulae
5455 | NGC 5455 | [
"Astronomy"
] | 161 | [
"Ursa Major",
"Constellations"
] |
77,289,419 | https://en.wikipedia.org/wiki/NGC%205461 | NGC 5461 is an emission nebula (HII region) located in Messier 101 (the Pinwheel Galaxy) towards the constellation Ursa Major. Eight other regions of Messier 101 are listed in the New General Catalogue, namely NGC 5447, NGC 5449, NGC 5450, NGC 5451, NGC 5453, NGC 5458, NGC 5461 and NGC 5462. Three of these regions were discovered by William Herschel (NGC 5447, NGC 5461 and NGC 5462) and the other six by Bindon Stoney.
See also
List of NGC objects (5001–6000)
Lists of nebulae
External links
NGC 5461 at NASA/IPAC
NGC 5461 at SIMBAD
NGC 5461 at LEDA
References
Emission nebulae
5461
Ursa Major | NGC 5461 | [
"Astronomy"
] | 169 | [
"Ursa Major",
"Constellations"
] |
77,289,420 | https://en.wikipedia.org/wiki/NGC%205471 | NGC 5471 is an emission nebula (HII region) located in Messier 101 (the Pinwheel Galaxy) towards the constellation Ursa Major. Eight other regions of Messier 101 are listed in the New General Catalogue, namely NGC 5447, NGC 5449, NGC 5450, NGC 5451, NGC 5453, NGC 5458, NGC 5461 and NGC 5462. Three of these regions were discovered by William Herschel (NGC 5447, NGC 5461 and NGC 5462) and the other six by Bindon Stoney.
NGC 5471 is however, unlike the nine other regions discovered by Herschel and Stoney, located on the outskirts of M101 and it was later discovered by d'Arrest in 1863. Furthermore, there is no agreement on its nature. For the Simbad database, it is a galaxy and for Professor Seligman, it is a cloud of stars.
The HyperLeda database indicates the PG rating for NGC 5471, therefore part of the galaxy. As for the NASA/IPAC database, it is mentioned that it is an HII region, but further on it is indicated under the morphology section that it is a Wolf-Rayet galaxy.
See also
List of NGC objects (5001–6000)
Lists of nebulae
External links
NGC 5471 at NASA/IPAC
NGC 5471 at SIMBAD
NGC 5471 at LEDA
References
Emission nebulae
5471
Ursa Major | NGC 5471 | [
"Astronomy"
] | 303 | [
"Ursa Major",
"Constellations"
] |
77,291,462 | https://en.wikipedia.org/wiki/Milestone-Based%20Fusion%20Development%20Program | The Milestone-Based Fusion Development Program is an ongoing program under the United States Department of Energy, office of fusion energy sciences to support the development of a fusion pilot plant (FPP) and eventually commercialize fusion power. As of 2024, eight private companies have received a total of $46 million for the first 18-month period of performance. The program is planned to run for five years and culminate in one or more fusion pilot plants.
History
The need for a fusion pilot plant has been recognized throughout the program to develop fusion power. Most recently before the announcement of the Milestone-Based Fusion Development Program, in 2021 the National Academies of Sciences, Engineering, and Medicine (NASEM) released a report which highlighted the need for such a program and advised its creation. In 2022 the Biden administration and DOE announced a Bold Decadal Vision for Commercial Fusion Energy which included plans to fund support for pilot plant development program.
The funding opportunity announcement (FOA) was announced by the US Department of Energy in September 2022, and $50 million was earmarked for the program.
Applications were received in December 2022. Eight companies were selected for negotiation in May 2023. However, agreements were not signed with the awardees until more than a year later in June 2024, reportedly due to concerns over how intellectual property would be handled.
In June 2024, at a White House summit the Department of Energy announced that all eight companies had successfully concluded detailed milestones negotiations with the federal government and that agreements had been signed to commence the Milestone Program.
Awardees
The eight awardees are:
Commonwealth Fusion Systems (Cambridge, MA)
Focused Energy Inc. (Austin, TX)
Thea Energy, Inc (formerly Princeton Stellarators Inc., Branchburg, NJ)
Realta Fusion Inc. (Madison, WI)
Tokamak Energy Inc. (US subsidiary of UK-based company, Bruceton Mills, WV)
Type One Energy Group (Madison, WI)
Xcimer Energy Inc. (Redwood City, CA)
Zap Energy Inc. (Everett, WA)
The awardees include 2 companies pursuing the tokamak approach, 2 companies pursuing the stellarator approach, 2 companies pursuing inertial confinement fusion, one company pursuing the magnetic mirror approach, and one company pursuing the Z-pinch approach.
Structure
The program is structured as a public–private partnership between the DOE and the awardees. The companies unlock matching funds upon completion of quantitative milestones, up to the full award amount.
The program is structured in three periods of performance: One spanning the first 18 months, one spanning the second 18 months, and one spanning the remaining 24 months of the five-year term. The first period of performance will presumably end around the end of 2025, assuming a start date based on the June 2024 announcement.
Only the first period of performance has been announced and awarded. The $46 million number is for the first period of performance. Subsequent periods of performance have not as of 2024 been announced, appropriated, or awarded.
The applicants were encouraged to propose collaborations with US national laboratories, with which the DOE would contract separately and pay directly. Oak Ridge National Laboratory will work with six of the eight companies.
Dispute over intellectual property
The year-long gap between the announcement of awardees and their signing agreements with the DOE was apparently due to a dispute over how companies' intellectual property would be treated under the award. Reporting stated that the companies' rights to existing and subject intellectual property was not sufficiently safeguarded under the DOE's initial proposed terms. At the time of the announcement, the total private investment in Commonwealth Fusion Systems was larger than $2 billion.
Awardee table
References
United States Department of Energy
Fusion power | Milestone-Based Fusion Development Program | [
"Physics",
"Chemistry"
] | 754 | [
"Nuclear fusion",
"Fusion power",
"Plasma physics"
] |
77,294,272 | https://en.wikipedia.org/wiki/Festival%20totem | Festival totems (sometimes known as doof sticks, rave totems, or rage sticks) are decorative objects, signs, toys, or symbols prominently displayed on poles by attendees at various music festivals and cultural events worldwide. Often seen in the crowds and campsites at large outdoor festivals, festival totems serve various purposes, ranging from artistic expression to utilitarian practical navigation and communication in large crowds. Typically, totems are DIY projects created by festival attendees, which are made from a variety of crafting materials and updated to reference current events, memes, music, or a festival, but have also recently become available to purchase online from totem creation companies.
Modern usage
The first totem use at a music festival is unconfirmed, with some attributing it to Woodstock in 1969. At contemporary music and arts festivals, totems are commonly used by groups of attendees to locate one another in crowded environments. Festivals such as Burning Man, Electric Daisy Carnival, Bonnaroo, Glastonbury, Electric Forest, and Tomorrowland have become known for their vibrant displays of totems and flags, which often feature unique handmade designs, humorous messages, current memes, or references to popular culture or the festival. A festival totem generally utilizes an object rather than a flag so that it can be easily seen fully in any wind conditions, and provide opportunity for 3D creativity. Most commonly referred to as a "totem" by festival attendees, the staffs also may be called "rage sticks" or "doof sticks" depending on the type of festival attended and the country of the festival.
Artists themselves have also encouraged the use of totems at their shows and may post how-to guides or videos for fans to learn how to add to the festival show experience. The popularity and restrictions on festival totems and flags have led to the appearance of custom manufacturers online.
Festival totems today may be utilized for a variety of purposes:
Group Locator: a festival totem's main purpose is generally to make it easy to identify the location of friends in the crowd.
Camp Locator: a festival totem may be placed at a campsite, like a flagpole might, to identify a camp location in large fields.
Identity Expression/Statements: a festival totem may make a personal or political statement, as it is hoisted up for thousands to see in person at the festival, on live streams, and in video recorded performances.
Artist/Crowd Communication: a festival totem may have a message an attendee hopes a performing artist will read, or words meant to attract or solicit conversations from other festival attendees in the crowd.
Safety and Security: a festival totem may be utilized by safety and security staff at festivals, especially during night, to attempt to locate a person in need or causing a disruption.
Historical comparisons and nomenclature
The concept of using "totems" and related staffs to indicate locations was prevalent in ancient armies before festival use. Festival totem carriers today use totems for group identification, which NAVA writers have analogized to vexilloids due to similar practical purposes. Throughout history, armies employed vexilloids as military standards, serving both practical and symbolic purposes; and in warfare, warriors would carry staffs, flags, and banners adorned with distinctive designs to distinguish allies from foes during battle. The first vexilloids were thought to originally be staffs topped by animal parts, like a skull. The staffs served as a designation for leaders of groups, such as military units, and were also used as a visible sign to rally around or point to a direction of attack. A specific example is the Romans using a vexillum, a military standard of the ancient Roman army carried by a vexillarius that attached a square cloth on a staff for similar purposes.
The "totem" name may have come from the comparison to Native American totem poles—festival totems are not as culturally or religiously significant as a totem pole, but similarly display artist creations, recent events, and stand tall to locate certain areas.
Design and materials
Festival totems can be crafted from a variety of materials, including wood, metal, plastic, foam, extendable poles, and fabric. The top of the totem may be a sign, a cutout image, a stuffed animal, or another object. Some festival totems are simple and utilitarian, such as poles attaching premade flags or signs, while others are intricate works of original art featuring LEDs, holographic materials, or kinetic elements that move with the wind or respond to music. Festival totems are usually distinct from flags on poles at festivals as totems generally contain an object and not loose cloth; however, both may be called a "totem" while being utilized in a festival crowd. Festival-goers frequently utilize memes, inside jokes, and other current event references to display on the totem.
Etiquette and regulations
Despite their practical benefits, totems have sparked debate within the festival community. With the primary function of festival totems serving as beacons to find groups in large crowds at shows to find friends at a distance, this leads to festival totems blocking the view of stages during shows. Festival attendees have opined that totems should not obstruct the view of others or interfere with the festival experience for fellow attendees and follow the PLUR rave community guidelines. Other attendees and publications note that festival totems supplement the festival experience and add artistic value to the festival while providing a crucial utilitarian purpose of finding friends in disorienting crowds at night.
Some organizers and attendees have raised concerns about safety and the potential for totems to block views of stages or performances. As a result, many festivals have implemented guidelines or restrictions regarding the size, material, height, and usage of totems.
References
Do it yourself
Festivals
Flags | Festival totem | [
"Mathematics"
] | 1,217 | [
"Symbols",
"Flags"
] |
77,295,256 | https://en.wikipedia.org/wiki/Austroboletus%20asper | Austroboletus asper is a species of bolete fungus found in Australia. It was described only recently identified in 2020 by the mycologists Roy Halling, Katrina Syme, Gregory Bonito, Teresa Lebel, and Nigel Fechner. The species name is derived from the Latin word asper meaning 'rough'. Austroboletus asper is an interesting mushroom-forming fungus species found amidst the eucalyptus forests of southeastern Australia and Tasmania. It features including a dry cap and a stem adorned with subtle reticulations. This species has a cap with a pale appendiculate margin, whose spores are Q ≥ 3.
According to the state of Queensland, Australia, it has no conservation significance as of 20 May 2024, which means that its existence is not at threat.
References
External sources
Mysterious Mushroom: Austroboletus asper Revealed - Garigal Country, Youtube by Mary Bell, 26 March 2024
asper
Fungi described in 2020
Fungi native to Australia
Fungus species
Taxa named by Teresa Lebel
Taxa named by Roy Halling | Austroboletus asper | [
"Biology"
] | 215 | [
"Fungi",
"Fungus species"
] |
75,663,993 | https://en.wikipedia.org/wiki/Einstein%20Probe | The Einstein Probe (EP) is an X-ray space telescope mission by Chinese Academy of Sciences (CAS) in partnership with European Space Agency (ESA) and the Max Planck Institute for Extraterrestrial Physics (MPE) dedicated to time-domain high-energy astrophysics. The primary goals are "to discover high-energy transients and monitor variable objects". The telescope was launched by a Long March 2C rocket from the Xichang Satellite Launch Centre in China, on 9 January 2024, at 07:03 UTC.
Scientific objectives
The primary science objectives are:
Identify inactive black holes to study how matter is precipitated there by detecting the transient events that take the form of X-ray flares;
Detect the electromagnetic counterpart of events triggering gravitational waves such as the merger of neutron stars which will be discovered by the next generation of gravitational wave detectors;
Carry out permanent monitoring of the entire sky to detect the various transient phenomena and carry out measurements of known variable X-ray sources.
Instruments
Einstein Probe carries 2 scientific instruments: the Wide-field X-ray Telescope (WXT), and the Follow-up X-ray Telescope (FXT). Both telescopes utilize X-ray focusing optics.
Wide-field X-ray Telescope (WXT): WXT has a new optics design, called "lobster-eye", that has wider field of view. "Lobster-eye" optics was first tested by the Lobster Eye Imager for Astronomy (LEIA) mission, launched in 2022. WXT consists of 12 Lobster-eye optics sensor modules, together creating a very large instantaneous field-of-view of 3600 square degrees. The nominal detection bandpass of WXT is 0.5~4.0 keV. Each module weighs 17 kg and has an electrical power consumption of just under 13 W. With the peripherals, the entire telescope weighs 251 kg and has a power consumption of 315 W.
Follow-up X-ray Telescope (FXT): FXT has optics adopted from eROSITA, "the mirror module consists of 54 nested Wolter mirrors with a focal length of 1600 mm and an effective area of greater than 300 cm2 at 1.5 keV."
The probe weights 1450 kg and is 3-by-3.4 metres.
Launch
Einstein Probe was launched on 9 January 2024, at 07:03 UTC by a Long March 2C rocket from the Xichang Satellite Launch Centre in China, and successfully placed in low Earth orbit at an altitude of 600 km and an inclination of 29 degrees, giving an orbital period of 96 minutes.
Findings
CAS reported that EP "performs as expected in the first month". The probe detected fast X-ray transient EP240315a, and bright X-ray flares EP240305a and EPW20240219aa.
On 15 March 2024, the Einstein Probe detected EP240315a, a soft X-ray burst from 12.5 billion light-years away, lasting over 17 minutes—the longest duration observed from such an ancient explosion. Linked to gamma-ray burst GRB 240315C, this event showed a six-minute delay between X-rays and gamma rays, never observed before. ESA notes that these findings challenge existing gamma-ray burst models.
See also
Timeline of artificial satellites and space probes
List of things named after Albert Einstein
X-ray astronomy
List of space telescopes#X-ray
References
Further reading
External links
at NAOC, CAS.
Einstein Probe at ESA.int
Einstein Probe at MPE.MPG.de
Space telescopes
X-ray telescopes
2024 in spaceflight
Chinese Academy of Sciences
E
Space probes launched in 2024 | Einstein Probe | [
"Astronomy"
] | 758 | [
"Space telescopes"
] |
75,664,310 | https://en.wikipedia.org/wiki/Valery%20Bakalov | Valery Panteleyevich Bakalov () was a Soviet and Russian scientist, Doctor of Engineering Sciences, professor, specialist in communications, information and measuring technology, theory of electrical circuits, the rector of Siberian State University of Telecommunications and Informatics (1987–2005).
Biography
He was born on September 19, 1940, in Novosibirsk. In 1963 Bakalov graduated from the Radio Engineering Faculty at Leningrad Electrotechnical Institute named after V. I. Ulyanov.
For seven years the scientist worked in one of the special designing and technological bureau (Leningrad), as well as at SB AS USSR (Novosibirsk), where he worked on problems related to radio telemetry.
In 1971, he began worked at the Novosibirsk Electrotechnical Institute of Communication (future Siberian State University of Telecommunications and Informatics). From 1987 to 2005, Bakalov was the rector of this educational institution.
He died on June 21, 2021, and was buried at the Zayeltsovskoye Cemetery in Novosibirsk.
Activities
The researcher contributed to the development of the general theory and methods for optimizing information and measurement systems with a spatially distributed structure. He oversaw programs for the creation of radio telemtric complexes, which were subsequently introduced into various sectors of national economy, and he was also involved in the informatization of Siberia and Far East.
Bakalov was one of the founders of such a scientific direction as biotelemetry.
He authored more than 200 scientific works and inventions, including 6 monographs and 10 textbooks for higher education institutions, as well as more than a dozen textbooks on the theory of electrical circuits and radiotelemetry.
References
20th-century Russian scientists
21st-century Russian engineers
Telecommunications engineers
Educators from Novosibirsk
Scientists from Novosibirsk
Burials at Zayeltsovskoye Cemetery
1940 births
2021 deaths | Valery Bakalov | [
"Engineering"
] | 385 | [
"Telecommunications engineering",
"Telecommunications engineers"
] |
75,664,937 | https://en.wikipedia.org/wiki/List%20of%20buildings%20in%20Guimar%C3%A3es | Guimarães, the first capital city of Portugal, is filled with a multitude of notable and historic buildings that fill its historic centre, a World Heritage Site due to its size and preservation, and other surrounding areas. This article serves as a comprehensive list of the many notable buildings in the city, divided into different categories, and organized following the alphabetical order system.
Historic landmarks
List of the numerous historical landmarks in Guimarães, from various distinct time periods, that had a big impact on the history of the city and of Portugal.
Residential buildings
List of notable buildings initially intended for residential use, mostly casas (houses) of rich and noble families.
Service buildings
List with notable buildings whose function is based on providing services, such as Hotels, Banks, Theatres, Factories…
Sport
Sports in Guimarães are largely influenced by Vitória S.C., with Moreirense F.C. also holding a significant position. Below is a compilation of notable sports-related venues and locations in Guimarães.
Demolished buildings
Monuments
See also
Guimarães
Historic Centre of Guimarães
History of Portugal
References
Architecture in Portugal
Guimarães
Guimarães | List of buildings in Guimarães | [
"Engineering"
] | 232 | [
"Architecture lists",
"Architecture"
] |
75,665,246 | https://en.wikipedia.org/wiki/Mikael%20Kubista | Mikael Kubista (born 13 August 1961) is a Czech-born Swedish chemist and entrepreneur who works in the field of molecular diagnostics. Since 2007, he is serving as a Professor of Chemistry and Head of the Department of Gene Expression Profiling at the Biotechnology Institute, Czech Academy of Sciences in the Czech Republic.
Kubista has contributed to the field of quantitative real-time PCR (qPCR), with his work recognized as part of the early research in this area.
Kubista was a member of the research team at Astra Hässle, where they focused on investigating Omeprazole, an inhibitor of K+/H+-ATPase. The drug is now marketed under the trade names Losec and Nexium, widely prescribed medications for the treatment of gastric ulcer. Additionally, Kubista is the Chairman of the Board of MultiD Analyses AB and the founder of TATAA Biocenter.
Early life
Kubista was born to his medical doctor father in the former Czechoslovakia in 1961. His father received a scholarship and relocated to Sweden. At the age of 7 in 1968, Kubista went to Sweden to visit his father. However, on that very day, Russia invaded Czechoslovakia in the so called Warsaw Pact invasion of Czechoslovakia, and as a result, the family decided to stay making Sweden their new home.
Education
He completed his undergraduate studies at University of Gothenburg, earning a B.Sc. degree in chemistry in 1984. He then pursued a Licentiate in Physical Chemistry at the Institute of Chemistry and Chemical Engineering, Chalmers University of Technology in Göteborg, which he completed in 1986. Kubista obtained his Ph.D. in chemistry from Chalmers University of Technology. Following his doctoral studies, he conducted postdoctoral research at institutions such as La Trobe University in Melbourne, Australia, and Yale University in New Haven, US. Additionally, he has held visiting professor positions at various universities, including the University of Maryland in College Park, US, in June 2000, and the University of A Coruña in Spain, during September–November 2003 and July 2006 to June 2007. Since 2007, Kubista is serving as an adjunct professor at the Institute of Biotechnology, Czech Academy of Sciences.
Career
Academic career
Kubista began his academic career in 1991 as an Assistant Professor in the Department of Physical Chemistry at Chalmers University of Technology. From 1993 to 1997, he served as an Associate Professor in the Department of Biochemistry at the same institution. Following this, he held the position of Professor in the Department of Biochemistry at Chalmers University of Technology from 1997 to 2006. Since 2007, he is the Head of the Department of Gene Expression at the Institute of Biotechnology, BIOCEV, Czech Academy of Sciences.
Entrepreneurial activities
In 1998 Kubista founded LightUp Technologies AB after his research finding of lightUp probes, a company that specializes in the development of real-time PCR tests for human infectious diseases. Three years later In 2001, Kubista's research led to the establishments of MultiD Analyses AB, which develops GenEx software for gene expression data analysis and TATAA Biocenter for qPCR and gene expression analysis. The company became known for its qPCR training services globally and its provision of qPCR services, particularly in Europe. TATAA Biocenter was the first laboratory in Europe to obtain flexible ISO 17025 accreditation and also was the first to provide COVID tests at the onset of the pandemic. In 2014 Kubista implemented non-invasive prenatal testing (NIPT) in Sweden and subsequently founded Life Genomics AB. In 2020, Kubista co-founded SimSen Diagnostics, a company focused on developing technology for liquid biopsy analyses.
Advisorial roles and memberships
Kubista holds several positions and advisory roles within the scientific and biotechnology communities including: Roche, ThermoFisher, Qiagen, Bio-Rad, and RealSeq Biosciences. He is also a member of the Scientific Advisory Council of Genetic Engineering News.
Kubista has also been involved in the establishment of modern molecular diagnostics in developing countries. Since 1999, he has served as an advisor to UNESCO, providing guidance and assistance to countries such as: Libya, Egypt, Iran, Grenada, and Ghana.
Kubista is an expert advisor for the European Commission Research Directorate General. Kubista advises the United Nations Educational Scientific and Cultural Organization (UNESCO) and is part of the scientific advisory board for the International Biotechnology Research in Tripoli, Libya, under UNESCO.
Selected findings and publications
Studied and identified chromophores and a variety of dyes commonly used as biomolecule labels like: tryptophan, DAPI, fluorescein, thiazole orange, and BEBO.
Explained DNA strand exchange in homologous recombination.
Applying Widlund experiment, identified specific nucleosome positioning sequences.
Uncovered mechanism of oncogene activation involving the formation of internal G-quadruplexes.
Designed a probe that exhibit luminescence upon binding to specific nucleic acids.
Techniques for gene expression at the level of individual cells and subcellular compartments.
The occurrence of horizontal transfer of mitochondria within living organisms.
Awards and recognition
Was recognized by ScholarGPS as one of the 50 highly ranked scholars of 2022.
In 2021 Kubista's organization, TATAA was on Sweden Technology Fast 50 list
In 2019, Global Health & Pharma recognized and awarded TATAA as the "Best Nucleic Acid Analysis Service Provider – Europe."
In 2013 TATAA Biocenter was honored with the Frost & Sullivan Award for Customer Value Leadership for their outstanding services in analyzing genetic material
In 2012, Pioneer of the year in western Sweden
In 1996, won Innovation Cup in western Sweden for the LightUp probes
References
1961 births
Living people
People from Podbořany
Biochemists
Molecular biologists
Swedish biochemists
University of Gothenburg alumni | Mikael Kubista | [
"Chemistry",
"Biology"
] | 1,213 | [
"Molecular biologists",
"Biochemists",
"Biochemistry",
"Molecular biology"
] |
75,666,186 | https://en.wikipedia.org/wiki/Apple%20Watch%20health%20monitoring%20patent%20dispute | In 2020, multinational technology company Apple Inc. entered into a patent dispute with health technology company Masimo and its subsidiary, Cercacor Laboratories, over alleged employee poaching attempts and patent infringement regarding the company's Apple Watches.
Background
The Apple Watch is a smartwatch developed by Apple, debuting in September 2014. The watch accounts for billion of Apple's annual sales and a third of all smartwatch sales. In October 2013, Cercacor Laboratories chief technology officer Marcelo Lamego emailed Apple chief executive Tim Cook with an idea for a new technology. Lamego began working for the company several weeks after the email was sent and began requesting Apple file a series of patents related to pulse oximetry within months of his employment. According to Masimo, Lamego initially declined to join Apple during a meeting between Masimo and Apple executives in 2013, but reconsidered after Masimo chief executive Joe Kiani appointed another employee as the company's chief technology officer. Lamego resigned in July 2014 after disputing with managers. According to Kiani, Apple hired thirty Masimo employees.
United States International Trade Commission bans may be vetoed by the President of the United States, or by the United States Trade Representative within sixty days of a ruling; vetoes are rare. In August 2013, then-trade representative Michael Froman vetoed a ruling preventing the iPhone 4 and select iPads from being sold in a patent dispute between Apple and Samsung. Trade representative Katherine Tai upheld a ban regarding electrocardiography technology and AliveCor in Apple Watches in February 2023.
Dispute
On January 9, 2020, Masimo and its subsidiary, Cercacor Laboratories, filed a lawsuit in the United States District Court for the Central District of California, alleging that Apple violated the company's light-based health monitoring patents. Masimo and Cercacor claimed that Apple's hiring of Cercacor chief technology officer Marcelo Lamego and Masimo chief medical officer Michael O'Reilly allowed Apple to gain a competitive advantage through their knowledge of Masimo's. The lawsuit seeks to block the use of Masimo's patents in the Apple Watch Series 4 and 5 and to seize seven patents issued to Lamego. Apple repeatedly filed to dismiss the allegations of obtaining trade secrets and filed petitions to invalidate Masimo's patents at the Patent and Trademark Office in September; Masimo accused these efforts of being attempts to delay the case in order to garner a greater share of the smartwatch market. In April 2023, deliberations began in the case. Judge James V. Selna dismissed the business and marketing claims against Apple and set the maximum fine against Apple at billion. The trial ended with a no jury verdict; the jury favored Apple, but a holdout juror refused to compromise.
In June 2021, Masimo expanded its lawsuit to encompass the Apple Watch Series 6, filing a complaint to the International Trade Commission to state that the Series 6 infringes five patents for Masimo's light-based pulse oximeters. The complaint was prompted by delays in the lawsuit, according to Masimo chief executive Joe Kiani. On October 26, 2023, the International Trade Commission issued an import ban against the Apple Watch Series 6, 7, 8, and 9 models set for December 26. Apple announced that it would halt sales of Apple Watch Series 9 and Ultra 2 models in retail locations on December 24 and online on December 21. The company has attempted to overturn the ban through software updates that would alter how oxygen saturation is determined. Apple lost an attempt to stay the ruling while awaiting an appeal and appealed the ruling to the Court of Appeals for the Federal Circuit. The federal appellate court granted Apple a temporary reprieve.
References
Further reading
Apple Watch
United States patent law | Apple Watch health monitoring patent dispute | [
"Technology"
] | 766 | [
"Smartwatches",
"Apple Watch"
] |
75,668,740 | https://en.wikipedia.org/wiki/4-Fluoroselegiline | 4-Fluoroselegiline, or p-fluoro-L-deprenyl, is a substituted amphetamine designer drug. It is the 4-fluorinated derivate of selegiline.
Pharmacology
Pharmacodynamics
4-Fluoroselegiline is a selective and irreversible inhibitor of monoamine oxidase B and monoaminergic activity enhancer.
A radiolabelled derivative incorporating 18F is used to study MAO-B inhibition in both in vivo and in vitro experiments.
Pharmacokinetics
4-Fluoro-deprenyl is metabolized to 4-Fluoromethamphetamine and 4-Fluoroamphetamine, both of which are active. The levels of substituted amphetamine metabolites in the brain is three times higher following 4-fluoroselegiline administration compared to an equivalent dose of selegiline.
Society and culture
Names
Synonyms of 4-fluoroselegiline or 4-fluorodeprenyl (the racemic form) include Chinoin-175, Fludepryl, and SR-96516-A.
References
4-Fluorophenyl compounds
Abandoned drugs
Monoaminergic activity enhancers
Propargyl compounds
Substituted amphetamines
Tertiary amines | 4-Fluoroselegiline | [
"Chemistry"
] | 280 | [
"Drug safety",
"Abandoned drugs"
] |
75,668,874 | https://en.wikipedia.org/wiki/Absolutely%20and%20completely%20monotonic%20functions%20and%20sequences | In mathematics, the notions of an absolutely monotonic function and a completely monotonic function are two very closely related concepts. Both imply very strong monotonicity properties. Both types of functions have derivatives of all orders. In the case of an absolutely monotonic function, the function as well as its derivatives of all orders must be non-negative in its domain of definition which would imply that the function as well as its derivatives of all orders are monotonically increasing functions in the domain of definition. In the case of a completely monotonic function, the function and its derivatives must be alternately non-negative and non-positive in its domain of definition which would imply that function and its derivatives are alternately monotonically increasing and monotonically decreasing functions.
Such functions were first studied by S. Bernshtein in 1914 and the terminology is also due to him. There are several other related notions like the concepts of almost completely monotonic function, logarithmically completely monotonic function, strongly logarithmically completely monotonic function, strongly completely monotonic function and almost strongly completely monotonic function. Another related concept is that of a completely/absolutely monotonic sequence. This notion was introduced by Hausdorff in 1921.
The notions of completely and absolutely monotone function/sequence play an important role in several areas of mathematics. For example, in classical analysis they occur in the proof of the positivity of integrals involving Bessel functions or the positivity of Cesàro means of certain
Jacobi series. Such functions occur in other areas of mathematics such as probability theory, numerical analysis, and elasticity.
Definitions
Functions
A real valued function defined over an interval in the real line is called an absolutely monotonic function if it has derivatives of all orders and for all in . The function is called a completely monotonic function if for all in .
The two notions are mutually related. The function is completely monotonic if and only if is absolutely monotonic on where the interval obtained by reflecting with respect to the origin. (Thus, if is the interval then is the interval .)
In applications, the interval on the real line that is usually considered is the closed-open right half of the real line, that is, the interval .
Examples
The following functions are absolutely monotonic in the specified regions.
, where a non-negative constant, in the region
, where for all , in the region
in the region
in the region
Sequences
A sequence is called an absolutely monotonic sequence if its elements are non-negative and its successive differences are all non-negative, that is, if
where .
A sequence is called a completely monotonic sequence if its elements are non-negative and its successive differences are alternately non-positive and non-negative, that is, if
Examples
The sequences and for are completely monotonic sequences.
Some important properties
Both the extensions and applications of the theory of absolutely monotonic functions derive from theorems.
The little Bernshtein theorem: A function that is absolutely monotonic on a closed interval can be extended to an analytic function on the interval defined by .
A function that is absolutely monotonic on can be extended to a function that is not only analytic on the real line but is even the restriction of an entire function to the real line.
The big Bernshtein theorem: A function that is absolutely monotonic on can be represented there as a Laplace integral in the form
where is non-decreasing and bounded on .
A sequence is completely monotonic if and only if there exists an increasing function on such that
The determination of this function from the sequence is referred to as the Hausdorff moment problem.
Further reading
The following is a selection from the large body of literature on absolutely/completely monotonic functions/sequences.
(Chapter 1 Laplace transforms and completely monotone functions)
See Chapter III The Moment Problem (pp. 100 - 143) and Chapter IV Absolutely and Completely Monotonic Functions (pp. 144 - 179).
(Chapter: "Completely Monotone Functions: A Digest")
See also
Bernstein's theorem on monotone functions
Hausdorff moment problem
Monotonic function
Cyclical monotonicity
References
Functional analysis
Order theory
Real analysis
Types of functions | Absolutely and completely monotonic functions and sequences | [
"Mathematics"
] | 842 | [
"Functions and mappings",
"Functional analysis",
"Mathematical objects",
"Mathematical relations",
"Order theory",
"Types of functions"
] |
75,668,939 | https://en.wikipedia.org/wiki/Dichlormid | Dichlormid is an organic compound with the formula . The compound can be classified as the amide of diallylamine and dichloroacetic acid. It is an herbicide safener for use with maize.
It can be synthesized by reacting diallylamine with dichloroacetyl chloride.
References
Herbicides
Allylamines
Acetamides
Organochlorides | Dichlormid | [
"Biology"
] | 83 | [
"Herbicides",
"Biocides"
] |
75,669,540 | https://en.wikipedia.org/wiki/Innovative%20Genomics%20Institute | The Innovative Genomics Institute (IGI) is an American nonprofit scientific research institute founded by Nobel laureate and CRISPR gene editing pioneer Jennifer Doudna and biophysicist Jonathan Weissman. The institute is based at the University of California, Berkeley, and also has member researchers at the University of California, San Francisco, UC Davis, UCLA, Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, Gladstone Institutes, and other collaborating research institutions. The IGI focuses on developing real-world applications of genome editing to address problems in human health, agriculture and climate change.
In addition to Doudna, current IGI directors and investigators include Jillian Banfield, who first introduced Doudna to CRISPR systems in bacteria in 2006, Fyodor Urnov, who coined the term "genome editing" with colleagues in 2005, as well as Alex Marson, Brian Staskawicz, and Pamela Ronald. The current executive director is Bradley Ringeisen, former director of the Biological Technologies Office at DARPA, who joined the IGI in 2020.
History
The first paper demonstrating the use of CRISPR-Cas9 as a programmable genome editing tool was published in 2012 by Doudna, Emmanuelle Charpentier and colleagues, work that would result in Doudna and Charpentier being awarded the 2020 Nobel Prize in Chemistry. Around this time, for-profit companies started forming to commercialize CRISPR in various ways, including Caribou Biosciences, Editas Medicine, and CRISPR Therapeutics. While Doudna was involved in some of commercial ventures, she also felt that a nonprofit institute could play a unique role in driving the science forward and helping develop ethical guidelines and equitable access to gene-editing technology in ways that market-driven companies would not, particularly because CRISPR held so much promise for addressing rare diseases that had often been neglected by the pharmaceutical industry.
The formation of the IGI was initially announced in March 2014 as the "Innovative Genomics Initiative", a partnership between UC Berkeley and UCSF researchers and biopharmaceutical industry partners with the aim of enhancing and genome-editing technology and applying it to drug development and global health, with funding support from the Li Ka Shing Foundation and the two universities. The official launch event was held on February 4, 2015. Early projects at the IGI focused on studying the use of CRISPR to address severe combined immunodeficiency disease and sickle cell disease. The IGI partnered with AstraZeneca and Agilent Technologies in 2015 to identify potential gene targets related to cancer, cardiovascular disease, autoimmune and inflammatory diseases, and other diseases with genetic components.
In January 2017, the IGI relaunched as the Innovative Genomics Institute and moved into their current building on the UC Berkeley campus. At the same time, new sources of funding allowed the institute expanded its scope to apply CRISPR and other genomic technologies to plants and agriculture, and the IGI brought in Brian Staskawicz as the director of this program. In early 2020, IGI co-founder Jonathan Weissman left UCSF and the IGI to take on the role of Landon T. Clay Professor of Biology at Whitehead Institute and professor of Biology at Massachusetts Institute of Technology.
On March 9, 2020, UC Berkeley announced the suspension in-person classes and began shutting down many campus buildings due to the COVID-19 pandemic. On March 13, 2020, Doudna convened a meeting with IGI leadership to discuss whether the institute should temporarily shut down. Instead, they decided to rapidly launch a diagnostic testing facility in the IGI building to provide testing to the UC Berkeley community as well as first responders and underserved populations in the surrounding cities. In addition to providing testing, the IGI awarded funding to support research studies into COVID-19 biology, epidemiology, public health impact, as well as novel diagnostics and therapeutic approaches. The IGI testing lab processed over 600,000 patient samples. Doudna has said that the IGI's experience with the COVID-19 response and rapid large-team science changed the way the institute selected projects moving forward because it showed how much impact can be made when researchers work together on a common goal.
On October 7, 2020, the Nobel Prize in Chemistry was awarded to Doudna and Charpentier for their work on developing CRISPR-Cas9 gene editing. Doudna was unable to attend the traditional live awards ceremony in Stockholm due to the COVID-19 pandemic, so she accepted the award at her home in Berkeley, California, and celebrations were held at the IGI building.
In October 2023, UC Berkeley announced plans to build a new "innovation zone" in downtown Berkeley with laboratory buildings that would provide new space for the IGI.
Research areas
IGI research centers around genome editing, incorporating researchers focused on human health applications, agricultural applications, development of genome-editing technology, and translation of lab discoveries into real-world solutions.
Advancing genome engineering
Since its founding, IGI researchers have discovered multiple new genome-editing proteins, expanding the toolkit beyond Cas9. The wave of discoveries of additional genome-editing tools with different properties, including new Cas proteins and techniques like base editing, was sometimes called "CRISPR 2.0" in popular science reporting. Ultra-compact proteins CasX and CasY were discovered by Jillian Banfield and collaborators at the IGI in some of the world's smallest microbes. Another compact Cas protein, CasΦ ("Cas phi"), was discovered by Banfield and Doudna and colleagues in the genomes of huge bacteriophages. Doudna and other IGI researchers have also advanced new techniques to improve non-viral and in vivo delivery of CRISPR-based therapeutics for medical applications, and worked on improving CRISPR safety and precision.
Human health
The IGI human health program has focused on developing therapies for rare and neglected genetic diseases and platform technology approaches to addressing rare diseases, including sickle cell disease and other blood and immune disorders. In 2021, the US Food and Drug Administration approved a clinical trial for an experimental CRISPR-based therapy for sickle cell disease developed by a consortium including the IGI, UCSF Benioff Children's Hospital, and the UCLA Broad Stem Cell Research Center. Other health research at the IGI focuses on cancer, neurodegenerative diseases, and clinical diagnostics.
Climate and sustainable agriculture
The IGI sustainable agriculture program and its Plant Genomics and Transformation Facility has developed CRISPR protocols for editing over 30 common crop species, and has worked on developing applications including protecting the world's chocolate supply from cacao swollen shoot virus, removing toxic cyanide precursors in cassava, and improving drought tolerance in rice.
In 2022, the IGI launched new programs to apply genome editing and genomic technologies to the challenge of mitigating and adapting to climate change. This work included efforts to reduce agricultural emissions, capture atmospheric carbon, and help farmers adapt to changing conditions. The Chan Zuckerberg Initiative committed $11 million to the IGI to support research on CRISPR-based approaches to enhancing the ability of plants and soils to remove and sequester atmospheric carbon.
At the 2023 TED conference in Vancouver, it was announced that the IGI was selected for funding by the Audacious Project and the institute received $70 million from donors to develop microbiome editing tools that can be applied to real-world problems related to human health and climate change. The project, entitled "Engineering the Microbiome with CRISPR to Improve our Climate and Health," is initially targeting two problems caused by microbiomes, methane emissions from livestock, and childhood asthma.
Public impact
An IGI team focuses on public impact works across disciplines to shape the impact of genome-editing research on society through research in ethics, law, economics, and policy.
In a meeting with US senators in December 2018, Doudna was asked about the potential high cost of a CRISPR-based treatment of sickle cell disease and what could be done to bring these costs down. When she returned to the IGI following this meeting, she decided to make affordability a part of the mission of the IGI, and a key goal for its sickle cell initiative.
In 2022, the IGI convened a group of 30 experts from diverse fields, including biotech, economics, manufacturing, venture capital, and intellectual property, to develop a plan to improve the affordability of genetic medicines. Current gene therapies and genome editing therapies can cost in the range of $2 to $3 million per patient. The group developed a report entitled "Making Genetic Therapies Affordable and Accessible" that developed strategies for reducing the cost of genetic medicines by a factor of 10 through a combination of new funding models, improved manufacturing, and alternative IP licensing approaches.
CRISPR education
In addition to CRISPR research, the IGI works to advance public understanding of CRISPR and genome engineering and guide the ethical use of these technologies. Free public resources include:
CRISPRpedia — a free textbook-style resource for learning about the biology, applications, and ethics of CRISPR and genome editing, with chapters edited by Doudna, Urnov, Ronald, and other IGI investigators.
CRISPR Made Simple — an educational guide to CRISPR for younger students and teachers.
CasPEDIA — a wiki-style database of the known CRISPR-associated (Cas) proteins, their activity and use cases, launched in 2023 by a group of researchers at the IGI.
CRISPR Clinical Trials — an annual summary of CRISPR-based therapies currently in clinical trials, broken down by disease area.
CRISPR in Agriculture — a summary of the progress in developing CRISPR applications in food and agriculture.
References
External links
Biotechnology
Genetics or genomics research institutions
University of California
University of California, Berkeley
University of California, San Francisco
Laboratories in the United States
Medical research institutes in the United States
Medical research institutes in California
Agricultural research institutes
Agricultural research institutes in the United States
Non-profit organizations based in California
Organizations based in Berkeley, California | Innovative Genomics Institute | [
"Biology"
] | 2,071 | [
"nan",
"Biotechnology"
] |
75,671,117 | https://en.wikipedia.org/wiki/Lobster-eye%20optics | Lobster-eye optics are a biomimetic design, based on the structure of the eyes of a lobster with an ultra wide field of view, used in X-ray optics. This configuration allows X-ray light to enter from multiple angles, capturing more X-rays from a larger area than other X-ray telescopes. The idea was originally proposed for use in X-ray astronomy by Roger Angel in 1979, with a similar idea presented earlier by W. K. H. Schmidt in 1975. It was first used by NASA on a sub-orbital sounding rocket experiment in 2012. The Lobster Eye Imager for Astronomy, a Chinese technology demonstrator satellite, was launched in 2022. The Chinese Einstein Probe, launched in 2024, is the first major space telescope to use lobster-eye optics. Several other such space telescopes are currently under development or consideration.
Description
While most animals have refractive eyes, lobsters and other crustaceans have reflective eyes. The eyes of a crustacean contain clusters of cells, each reflecting a small amount of light from a particular direction. Lobster-eye optics technology mimics this reflective structure. This arrangement allows the light from a wide viewing area to be focused into a single image. The optics are made of microchannel plates. X-ray light can enter small tubes within these plates from multiple angles, and is focused through grazing-incidence reflection that gives a wide field of view. That, in turn, makes it possible to locate and image transient astronomical events that could not have been predicted in advance.
The field of view (FoV) of a lobster-eye optic, which is the solid angle subtended by the optic plate to the curvature center, is limited only by the optic size for a given curvature radius. Since the micropore optics are spherically symmetric in essentially all directions, theoretically, an idealized lobster-eye optic is almost free from vignetting except near the edge of the FoV. Micropore imagers are created from several layers of lobster-eye optics that creates an approximation of Wolter type-I optical design.
History
Only three geometries that use grazing incidence reflection of X-rays to produce X-ray images are known: the Wolter system, the Kirkpatrick-Baez system, and the lobster-eye geometry.
The lobster-eye X-ray optics design was first proposed in 1979 by Roger Angel. His design is based on Kirkpatrick-Baez optics, but requires pores with a square cross-section, and is referred to as the "Angel multi-channel lens". This design was inspired directly by the reflective properties of lobster eyes. Before Angel, an alternative design involving a one-dimensional arrangement consisting of a set of flat reflecting surfaces had been proposed by W. K. H. Schmidt in 1975, known as the "Schmidt focusing collimator objective". In 1989, physicists Keith Nugent and Stephen W. Wilkins collaborated to develop lobster-eye optics independently of Angel. Their key contribution was to open up an approach to manufacturing these devices using microchannel plate technology. This lobster-eye approach paved the way for X-ray telescopes with a 360-degree view of the sky.
In 1992, Philip E. Kaaret and Phillip Geissbuehler proposed a new method for creating lobster-eye optics with microchannel plates. Micropores required for lobster-eye optics are difficult to manufacture and have strict requirements. The pores must have widths between 0.01 and 0.5 mm and should have a length-to-width ratio of 20–200 (depends on the X-ray energy range); they need to be coated with a dense material for optimal X-ray reflection. The pore's inner walls must be flat and they should be organized in a dense array on a spherical surface with a radius of curvature of 2F, ensuring an open fraction greater than 50% and pore alignment accuracy between 0.1 and 5 arc minutes towards a common center.
Similar optics designs include honeycomb collimators (used in NEAR Shoemaker's XGRS detectors and MESSENGER's XRS) and silicon pore imagers (developed by ESA for its planned ATHENA mission).
Uses
NASA launched the first lobster-eye imager on a Black Brant IX sub-orbital sounding rocket in 2012. The STORM/DXL instrument (Sheath Transport Observer for the Redistribution of Mass/Diffuse X-ray emission from the Local galaxy) had micropore reflectors arranged in an array to form a Kirkpatrick-Baez system. BepiColombo, a joint ESA and JAXA Mercury mission launched in 2018, has a non-imaging collimator MIXS-C, with a microchannel geometry similar to the lobster-eye micropore design.
CNSA launched the Lobster-Eye X-ray Satellite in 2020, the first in-orbit lobster-eye telescope. In 2022, the Chinese Academy of Sciences built and launched the Lobster Eye Imager for Astronomy (LEIA), a wide-field X-ray imaging space telescope. It is a technology demonstrator mission that tests the sensor design for the Einstein Probe. LEIA has a sensor module that gives it a field of view of 340 square degrees. In August and September of 2022, LEIA conducted measurements to verify its functionality. A number of preselected sky regions and targets were observed, including the Galactic Center, the Magellanic Clouds, Sco X-1, Cas A, Cygnus Loop, and a few extragalactic sources. To eliminate interference from sunlight, the observations were obtained in Earth's shadow, starting 2 minutes after the satellite entered the shadow and ending 10 minutes before leaving it, resulting in an observational duration of ~23 minutes in each orbit. The CMOS detectors were operating in the event mode.
Current and future space telescopes
The Einstein Probe, a joint mission by the Chinese Academy of Sciences (CAS) in partnership with the European Space Agency (ESA) and the Max Planck Institute for Extraterrestrial Physics, was launched on 9 January 2024. It uses a 12-sensor module wide-field X-ray telescope for a 3600 square degree field of view, first tested by the Lobster Eye Imager for Astronomy mission.
The joint French-Chinese SVOM was launched on 22 June 2024.
NASA's Goddard Space Center proposed an instrument that uses the lobster-eye design for the ISS-TAO mission (Transient Astrophysics Observatory on the International Space Station), called the X-ray Wide-Field Imager. ISS-Lobster is a similar concept by ESA.
Several space telescopes that use lobster-eye optics are under construction. SMILE, a space telescope project by ESA and CAS, is planned to be launched in 2025. ESA's THESEUS is now under consideration.
Other uses
Lobster-eye optics can also be used for backscattering imaging for homeland security, detection of improvised explosive devices, nondestructive testing, and medical imaging.
References
Optics
Optics
Optics
Optics
Bioinspiration
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75,672,385 | https://en.wikipedia.org/wiki/Statue%20of%20Shakira | The bronze statue of Colombian singer Shakira stands at the Gran Malecon de Barranquilla, in Barranquilla, Colombia.
This bronze statue is the second biggest pop icon statue only behind Forever Marilyn, a 26-ft tribute to Marilyn Monroe that sits outside a tourism agency in Palm Springs, California,
Sculpture
The statue, which resembles Shakira's signature pose and hip swivel from her 2005 "Hips Don't Lie" music video, was sculpted by 52-year-old sculptor Yino Marquez. Marquez, with a career spanning from the age of 16, has crafted large statues for Colombian cities and serves as an academic coordinator in Barranquilla’s public art academy. Mayor Jaime Pumarejo proposed the idea of a Shakira statue for the waterfront, and a month later, Marquez was chosen. The city aimed to honor Barranquilla figures to boost tourism and provide role models, resulting in two statues—one representing the city's coat of arms and another of Shakira. The project cost around $700 million Colombian pesos (USD$180,000). Over 30 people worked on the sculpture over the course of five months.
A plaque beneath the statue reads: "A heart that composes, hips that don't lie, unmatched talent, a voice that moves the masses, and bare feet that march for the good of children and humanity." The sculpture is located on a promenade along the Magdalena River.
Reception
Shakira expressed in a social media post about the statue dedication, "This is too much for my little heart." She shared her happiness at having her parents present on her mother's birthday during the ceremony and extended gratitude to the statue's sculptor and the students from a local arts school. She has not seen it yet in person according to her interview with Zane Lowe on Apple Music.
Sculpture of Shakira in Barranquilla
This is the second monumental sculpture of the Colombian artist located in Barranquilla. Since 2006, a no less representative one has been displayed in the park of the Estadio Metropolitano Roberto Meléndez, the largest stadium in Colombia. The Shakira sculpture made of steel represents the singer and songwriter standing with a guitar.
References
2023 sculptures
Barranquilla
Bronze sculptures in Colombia
Outdoor sculptures in Colombia
Shakira
Sculptures of women in Colombia
Statues in Colombia
Colossal statues
2023 establishments in Colombia | Statue of Shakira | [
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75,672,615 | https://en.wikipedia.org/wiki/Raymond%20A.%20Young | Raymond Allen Young (born March 14, 1945) is an American materials researcher, wood scientist and emeritus professor at the University of Wisconsin-Madison, who is an elected fellow (FIAWS) of the International Academy of Wood Science.
Biography
Young was born in Buffalo, New York and grew up in Syracuse. He graduated from the Central Technical High School in Syracuse in 1962, and earned a bachelor of science degree in Wood Products Engineering from the State University of New York (SUNY) and Syracuse University in 1966. He also obtained a MSc degree in Cellulose Chemistry from SUNY-Syracuse University in 1968.
From 1968 to 1969, he worked as a process supervisor in pulp and paper production at Kimberly-Clark Corp. in Niagara Falls, New York. He then pursued his doctorate studies, including a Fulbright scholarship in 1972 at the Royal Institute of Technology in Stockholm, Sweden. He eventually obtained his PhD degree in Wood and Polymer Chemistry from the University of Washington at Seattle in October 1973 under the guidance of Professor K.V. Sarkanen. He also held in years 1973-1975 a post-doctoral fellowship in fiber chemistry at the Textile Research Institute in Princeton, NJ, which was associated with the Princeton University.
Between 1975 and 2004, Young served as a researcher and professor in the Department of Forestry at the University of Wisconsin in Madison, Wisconsin, focusing on wood chemistry and natural products chemistry. He has been a visiting professor and scholar at several research institutes and universities in Sweden, China, Japan, New Zealand, Mexico, Indonesia, Taiwan, Brazil, Turkey, and Greece. He served as a member in the editorial boards of the journals, Wood Science and Technology, and Wood and Fiber Science. Since 2004, he has held the title of emeritus professor at the University of Wisconsin-Madison.
His scientific work includes more than 180 research papers, eight books and nine international patents. Young's primary research work, which has received until June 2024 almost 7,000 international citations (h-index: 48), has focused mostly on the plasma modification of natural and synthetic materials, bonding and adhesion in composite materials, new wood pulping methods, and the chemistry of natural products.
Recognition
In 1997, Young was elected as a Fellow at the International Academy of Wood Science (IAWS) for his yearlong research contributions in the area of wood chemistry and science.
Young and Denes were among the first scientists who initiated research studies on plasma chemistry of cellulosic fibers during the '90s.
Throughout his career, Young has received several awards for his research work:
Wisconsin Governor's Energy Innovation Award (2004)
Senior Fulbright Scholar - Aristotle University of Thessaloniki, Greece (1989)
Japanese Photopolymer Award - Plasma Chemistry (2000)
National Academy of Scientific Exchange Award - 1st in Poland (1979) & in former Yugoslavia (1979); 2nd in Romania (1990)
In October 2023, a referenced meta-research conducted by John Ioannidis and his team at Stanford University included R.A. Young in the Elsevier Data 2022, where he was ranked in the top 2% of researchers of all time in wood chemistry (polymers – forestry), having a c-index 3.170.
Personal life
Young lives permanently in Sarasota, Florida with his second wife, Kathryn Young. From his first marriage, Young has had two sons, Tim and Erik. Tim Young is a university professor of astrophysics at the University of North Dakota.
During his retirement, Young has written some non-scientific books, namely, "Polynesian and the Polynesians: An Overview", "Perfumes and Perfumery: An Overview", "A Sabbatical in Greece: Thessaloniki and Mt Athos", and one book about his family heritage entitled, "Young Family Genealogy: From the Coal Mines & Steel Mills".
Scientific books
Young has published several scientific books:
Modified Cellulosics (1978), by Roger M. Rowell and Raymond A. Young, Academic Press, ASIN: B01D4CHXS2, 592 pp.
Introduction to Forest Ecosystem Science and Management (2003), by Raymond A. Young and Ronald L. Giese, Wiley, , 592 pp.
Environmentally Friendly Technologies for the Pulp and Paper Industry (1998), by Raymond A. Young and Masood Akhtar, Eds. Wiley, , 592 pp.
Paper and Composites from Agro-Based Resources (1997), by Roger M. Rowell, Raymond A. Young, Judith Rowell, CRC Press, , 464 pp.
Cellulose: Structure, Modification and Hydrolysis (1986), by Raymond A. Young and Roger M. Rowell, Krieger Pub Co, , 400 pp.
Introduction to Forest Science (1982 & 1990), by Raymond A. Young, Wiley, , 554 pp.
References
External links
Google Scholar
ResearchGate
University of Wisconsin–Madison faculty
University of Washington alumni
American scientists
Fellows of the International Academy of Wood Science
Wood scientists
1945 births
Living people | Raymond A. Young | [
"Materials_science"
] | 1,018 | [
"Wood sciences",
"Wood scientists"
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75,672,633 | https://en.wikipedia.org/wiki/Tremella%20exigua | Tremella exigua is a species of fungus in the family Tremellaceae. It produces small, dark, pustular, gelatinous basidiocarps (fruit bodies) and is parasitic on pyrenomycetous fungi (Diaporthe and Cucurbitaria species) on dead branches of trees and shrubs. It was originally described from France.
Taxonomy
Tremella exigua was first published in 1847 by French mycologist John Baptiste Desmazières based on a collection from France on a dead branch of ash (Fraxinus excelsior).
Swedish mycologist Elias Magnus Fries had earlier described Agyrium atrovirens, a species interpreted as synonymous with T. exigua, on the same host tree from Sweden. The name is not available in Tremella, however, since the combination Tremella atrovirens is an illegitimate homonym of the earlier, unrelated T. atrovirens Bull.
Tremella genistae, described from Belgium on broom (Cytisus scoparius), is considered a further synonym. The name Tremella virescens Schumach. has also been used for this species, but its interpretation is doubtful.
Initial molecular research, based on cladistic analysis of DNA sequences, suggests that Tremella exigua is not closely related to Tremella sensu stricto, but belongs in a separate (but as yet unnamed) genus in the family Bulleraceae.
Description
Fruit bodies are gelatinous, olive-black, up to 8 mm across, pustular at first, sometimes becoming cerebriform (brain-like). Microscopically, the hyphae have clamp connections and the basidia are tremelloid (globose to clavate, with oblique septa), 4-celled, 18 to 36 by 8 to 15 μm. Basidiospores are globose to subglobose 7 to 10 by 6.5 to 10 μm in diameter.
Similar species
Gelatinous fruit bodies of Tremella globispora and Tremella indecorata are of similar size and shape and have also been recorded as parasites of Diaporthe species, but are hyaline (colourless) or whitish to brown, without green or black tints. Species of Nostoc are greenish black and gelatinous, but are cyanobacteria (not fungi) and form growths that are typically more extensive and often terrestrial.
Habitat and distribution
Tremella exigua is a parasite on lignicolous pyrenomycetes, including species of Diaporthe and Cucurbitaria. Though originally described from ash, the species is more commonly found on dead branches of gorse (Ulex europaeus), broom (Cytisus scoparius), and barberry (Berberis vulgaris).
The species was originally described from France and has been widely recorded in Europe. Tremella exigua has also been reported from Canada and Ecuador.
References
exigua
Fungi of Europe
Fungi described in 1847
Fungus species | Tremella exigua | [
"Biology"
] | 652 | [
"Fungi",
"Fungus species"
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75,674,975 | https://en.wikipedia.org/wiki/Printed%20circuit%20board%20manufacturing | Printed circuit board manufacturing is the process of manufacturing bare printed circuit boards (PCBs) and populating them with electronic components. It includes all the processes to produce the full assembly of a board into a functional circuit board.
In board manufacturing, multiple PCBs are grouped on a single panel for efficient processing. After assembly, they are separated (depaneled). Various techniques, such as silk screening and photoengraving, replicate the desired copper patterns on the PCB layers. Multi-layer boards are created by laminating different layers under heat and pressure. Holes for vias (vertical connections between layers) are also drilled.
The final assembly involves placing components onto the PCB and soldering them in place. This process can include through-hole technology (in which the component goes through the board) or surface-mount technology (SMT) (in which the component lays on top of the board).
Design
Manufacturing starts from the fabrication data generated by computer aided design, and component information. The fabrication data is read into the CAM (Computer Aided Manufacturing) software. CAM performs the following functions:
Input of the fabrication data.
Verification of the data
Compensation for deviations in the manufacturing processes (e.g. scaling to compensate for distortions during lamination)
Panelization
Output of the digital tools (copper patterns, drill files, inspection, and others)
Initially PCBs were designed manually by creating a photomask on a clear mylar sheet, usually at two or four times the true size. Starting from the schematic diagram the component pin pads were laid out on the mylar and then traces were routed to connect the pads. Rub-on dry transfers of common component footprints increased efficiency. Traces were made with self-adhesive tape. Pre-printed non-reproducing grids on the mylar assisted in layout. The finished photomask was photolithographically reproduced onto a photoresist coating on the blank copper-clad boards.
Modern PCBs are designed with dedicated layout software, generally in the following steps:
Schematic capture through an electronic design automation (EDA) tool.
Card dimensions and template are decided based on required circuitry and enclosure of the PCB.
The positions of the components and heat sinks are determined.
Layer stack of the PCB is decided, with one to tens of layers depending on complexity. Ground and power planes are decided. A power plane is the counterpart to a ground plane and behaves as an AC signal ground while providing DC power to the circuits mounted on the PCB. Signal interconnections are traced on signal planes. Signal planes can be on the outer as well as inner layers. For optimal EMI performance high frequency signals are routed in internal layers between power or ground planes.
Line impedance is determined using dielectric layer thickness, routing copper thickness and trace-width. Trace separation is also taken into account in case of differential signals. Microstrip, stripline or dual stripline can be used to route signals.
Components are placed. Thermal considerations and geometry are taken into account. Vias and lands are marked.
Signal traces are routed. Electronic design automation tools usually create clearances and connections in power and ground planes automatically.
Fabrication data consists of a set of Gerber format files, a drill file, and a pick-and-place file.
Panelization
Several small printed circuit boards can be grouped together for processing as a panel. A panel consisting of a design duplicated n-times is also called an n-panel, whereas a multi-panel combines several different designs onto a single panel. The outer tooling strip often includes tooling holes, a set of panel fiducials, a test coupon, and may include hatched copper pour or similar patterns for even copper distribution over the whole panel in order to avoid bending. The assemblers often mount components on panels rather than single PCBs because this is efficient. Panelization may also be necessary for boards with components placed near an edge of the board because otherwise the board could not be mounted during assembly. Most assembly shops require a free area of at least 10 mm around the board.
Depaneling
The panel is eventually broken into individual PCBs along perforations or grooves in the panel through milling or cutting. For milled panels a common distance between the individual boards is 2–3 mm. Today depaneling is often done by lasers which cut the board with no contact. Laser depaneling reduces stress on the fragile circuits, improving the yield of defect-free units.
Copper patterning
The first step is to replicate the pattern in the fabricator's CAM system on a protective mask on the copper foil PCB layers. Subsequent etching removes the unwanted copper unprotected by the mask. (Alternatively, a conductive ink can be ink-jetted on a blank (non-conductive) board. This technique is also used in the manufacture of hybrid circuits.)
Silk screen printing uses etch-resistant inks to create the protective mask.
Photoengraving uses a photomask and developer to selectively remove a UV-sensitive photoresist coating and thus create a photoresist mask that will protect the copper below it. Direct imaging techniques are sometimes used for high-resolution requirements. Experiments have been made with thermal resist. A laser may be used instead of a photomask. This is known as maskless lithography or direct imaging.
PCB milling uses a two or three-axis mechanical milling system to mill away the copper foil from the substrate. A PCB milling machine (referred to as a 'PCB Prototyper') operates in a similar way to a plotter, receiving commands from the host software that control the position of the milling head in the x, y, and (if relevant) z axis.
Laser resist ablation involves spraying black paint onto copper clad laminate, then placing the board into CNC laser plotter. The laser raster-scans the PCB and ablates (vaporizes) the paint where no resist is wanted. (Note: laser copper ablation is rarely used and is considered experimental.)
Laser etching, in which the copper may be removed directly by a CNC laser. Like PCB milling above, this is used mainly for prototyping.
EDM etching uses an electrical discharge to remove a metal from a substrate submerged into a dielectric fluid.
The method chosen depends on the number of boards to be produced and the required resolution.
Large volume
Silk screen printing – Used for PCBs with bigger features
Photoengraving – Used when finer features are required
Small volume
Print onto transparent film and use as photo mask along with photo-sensitized boards, then etch. (Alternatively, use a film photoplotter.)
Laser resist ablation
PCB milling
Laser etching
Hobbyist
Laser-printed resist: Laser-print onto toner transfer paper, heat-transfer with an iron or modified laminator onto bare laminate, soak in water bath, touch up with a marker, then etch.
Vinyl film and resist, non-washable marker, some other methods. Labor-intensive, only suitable for single boards.
Etching
The process by which copper traces are applied to the surface is known as etching after the subtractive method of the process, though there are also additive and semi-additive methods.
Subtractive methods remove copper from an entirely copper-coated board to leave only the desired copper pattern. The simplest method, used for small-scale production and often by hobbyists, is immersion etching, in which the board is submerged in etching solution such as ferric chloride. Compared with methods used for mass production, the etching time is long. Heat and agitation can be applied to the bath to speed the etching rate. In bubble etching, air is passed through the etchant bath to agitate the solution and speed up etching. Splash etching uses a motor-driven paddle to splash boards with etchant; the process has become commercially obsolete since it is not as fast as spray etching. In spray etching, the etchant solution is distributed over the boards by nozzles, and recirculated by pumps. Adjustment of the nozzle pattern, flow rate, temperature, and etchant composition gives predictable control of etching rates and high production rates. As more copper is consumed from the boards, the etchant becomes saturated and less effective; different etchants have different capacities for copper, with some as high as 150 grams of copper per liter of solution. In commercial use, etchants can be regenerated to restore their activity, and the dissolved copper recovered and sold. Small-scale etching requires attention to disposal of used etchant, which is corrosive and toxic due to its metal content. The etchant removes copper on all surfaces not protected by the resist. "Undercut" occurs when etchant attacks the thin edge of copper under the resist; this can reduce conductor widths and cause open-circuits. Careful control of etch time is required to prevent undercut. Where metallic plating is used as a resist, it can "overhang" which can cause short circuits between adjacent traces when closely spaced. Overhang can be removed by wire-brushing the board after etching.
In additive methods the pattern is electroplated onto a bare substrate using a complex process. The advantage of the additive method is that less material is needed and less waste is produced. In the full additive process the bare laminate is covered with a photosensitive film which is imaged (exposed to light through a mask and then developed which removes the unexposed film). The exposed areas are sensitized in a chemical bath, usually containing palladium and similar to that used for through hole plating which makes the exposed area capable of bonding metal ions. The laminate is then plated with copper in the sensitized areas. When the mask is stripped, the PCB is finished.
Semi-additive is the most common process: The unpatterned board has a thin layer of copper already on it. A reverse mask is then applied (Unlike a subtractive process mask, this mask exposes those parts of the substrate that will eventually become the traces). Additional copper is then plated onto the board in the unmasked areas; copper may be plated to any desired weight. Tin-lead or other surface platings are then applied. The mask is stripped away and a brief etching step removes the now-exposed bare original copper laminate from the board, isolating the individual traces. Some single-sided boards which have plated-through holes are made in this way. General Electric made consumer radio sets in the late 1960s using additive boards. The (semi-)additive process is commonly used for multi-layer boards as it facilitates the plating-through of the holes to produce conductive vias in the circuit board.
Industrial etching is usually done with ammonium persulfate or ferric chloride. For PTH (plated-through holes), additional steps of electroless deposition are done after the holes are drilled, then copper is electroplated to build up the thickness, the boards are screened, and plated with tin/lead. The tin/lead becomes the resist leaving the bare copper to be etched away.
Lamination
Multi-layer printed circuit boards have trace layers inside the board. This is achieved by laminating a stack of materials in a press by applying pressure and heat for a period of time. This results in an inseparable one piece product. For example, a four-layer PCB can be fabricated by starting from a two-sided copper-clad laminate, etch the circuitry on both sides, then laminate to the top and bottom pre-preg and copper foil. It is then drilled, plated, and etched again to get traces on top and bottom layers.
The inner layers are given a complete machine inspection before lamination because mistakes cannot be corrected afterwards. Automatic optical inspection (AOI) machines compare an image of the board with the digital image generated from the original design data. Automated Optical Shaping (AOS) machines can then add missing copper or remove excess copper using a laser, reducing the number of PCBs that have to be discarded. PCB tracks can have a width of just 10 micrometers.
Drilling
Holes through a PCB are typically drilled with drill bits coated with tungsten carbide. Coated tungsten carbide is used because board materials are abrasive. High-speed-steel bits would dull quickly, tearing the copper and ruining the board. Drilling is done by computer-controlled drilling machines, using a drill file or Excellon file that describes the location and size of each drilled hole.
Vias
Holes may be made conductive, by electroplating or inserting hollow metal eyelets, to connect board layers. Some conductive holes are intended for the insertion of through-hole-component leads. Others used to connect board layers, are called vias.
Micro vias
When vias with a diameter smaller than 76.2 micrometers are required, drilling with mechanical bits is impossible because of high rates of wear and breakage. In this case, the vias may be laser drilled—evaporated by lasers. Laser-drilled vias typically have an inferior surface finish inside the hole. These holes are called micro vias and can have diameters as small as 10 micrometers.
Blind and buried vias
It is also possible with controlled-depth drilling, laser drilling, or by pre-drilling the individual sheets of the PCB before lamination, to produce holes that connect only some of the copper layers, rather than passing through the entire board. These holes are called blind vias when they connect an internal copper layer to an outer layer, or buried vias when they connect two or more internal copper layers and no outer layers. Laser drilling machines can drill thousands of holes per second and can use either UV or lasers.
The hole walls for boards with two or more layers can be made conductive and then electroplated with copper to form plated-through holes. These holes electrically connect the conducting layers of the PCB.
Smear
For multi-layer boards, those with three layers or more, drilling typically produces a smear of the high temperature decomposition products of bonding agent in the laminate system. Before the holes can be plated through, this smear must be removed by a chemical de-smear process, or by Plasma etching. The de-smear process ensures that a good connection is made to the copper layers when the hole is plated through. On high reliability boards a process called etch-back is performed chemically with a potassium permanganate based etchant or plasma etching. The etch-back removes resin and the glass fibers so that the copper layers extend into the hole and as the hole is plated become integral with the deposited copper.
Plating and coating
Proper plating or surface finish selection can be critical to process yield, the amount of rework, field failure rate, and reliability.
PCBs may be plated with solder, tin, or gold over nickel.
After PCBs are etched and then rinsed with water, the solder mask is applied, and then any exposed copper is coated with solder, nickel/gold, or some other anti-corrosion coating.
It is important to use solder compatible with both the PCB and the parts used. An example is ball grid array (BGA) using tin-lead solder balls for connections losing their balls on bare copper traces or using lead-free solder paste.
Other platings used are organic solderability preservative (OSP), immersion silver (IAg), immersion tin (ISn), electroless nickel immersion gold (ENIG) coating, electroless nickel electroless palladium immersion gold (ENEPIG), and direct gold plating (over nickel). Edge connectors, placed along one edge of some boards, are often nickel-plated then gold-plated using ENIG. Another coating consideration is rapid diffusion of coating metal into tin solder. Tin forms intermetallics such as Cu6Sn5 and Ag3Cu that dissolve into the Tin liquidus or solidus (at 50 °C), stripping surface coating or leaving voids.
Electrochemical migration (ECM) is the growth of conductive metal filaments on or in a printed circuit board (PCB) under the influence of a DC voltage bias. Silver, zinc, and aluminum are known to grow whiskers under the influence of an electric field. Silver also grows conducting surface paths in the presence of halide and other ions, making it a poor choice for electronics use. Tin will grow "whiskers" due to tension in the plated surface. Tin-lead or solder plating also grows whiskers, only reduced by reducing the percentage of tin. Reflow to melt solder or tin plate to relieve surface stress lowers whisker incidence. Another coating issue is tin pest, the transformation of tin to a powdery allotrope at low temperature.
Solder resist application
Areas that should not be soldered may be covered with solder resist (solder mask). The solder mask is what gives PCBs their characteristic green color, although it is also available in several other colors, such as red, blue, purple, yellow, black and white. One of the most common solder resists used today is called "LPI" (liquid photoimageable solder mask). A photo-sensitive coating is applied to the surface of the PWB, then exposed to light through the solder mask image film, and finally developed where the unexposed areas are washed away. Dry film solder mask is similar to the dry film used to image the PWB for plating or etching. After being laminated to the PWB surface it is imaged and developed as LPI. Once but no longer commonly used, because of its low accuracy and resolution, is to screen print epoxy ink. In addition to repelling solder, solder resist also provides protection from the environment to the copper that would otherwise be exposed.
Legend / silkscreen
A legend (also known as silk or silkscreen) is often printed on one or both sides of the PCB. It contains the component designators, switch settings, test points and other indications helpful in assembling, testing, servicing, and sometimes using the circuit board.
There are three methods to print the legend:
Silkscreen printing epoxy ink was the established method, resulting in the alternative name.
Liquid photo imaging is a more accurate method than screen printing.
Inkjet printing is increasingly used. Inkjet printers can print variable data, unique to each PCB unit, such as text, a serial number, or a bar code.
Bare-board test
Boards with no components installed are usually bare-board tested for "shorts" and "opens". This is called electrical test or PCB e-test. A short is a connection between two points that should not be connected. An open is a missing connection between points that should be connected. For high-volume testing, a rigid needle adapter makes contact with copper lands on the board. The fixture or adapter is a significant fixed cost and this method is only economical for high-volume or high-value production. For small or medium volume production flying probe testers are used where test probes are moved over the board by an XY drive to make contact with the copper lands. There is no need for a fixture and hence the fixed costs are much lower. The CAM system instructs the electrical tester to apply a voltage to each contact point as required and to check that this voltage appears on the appropriate contact points and only on these.
Assembly
In assembly the bare board is populated (or "stuffed") with electronic components to form a functional printed circuit assembly (PCA), sometimes called a "printed circuit board assembly" (PCBA). In through-hole technology, the component leads are inserted in holes surrounded by conductive pads; the holes keep the components in place. In surface-mount technology (SMT), the component is placed on the PCB so that the pins line up with the conductive pads or lands on the surfaces of the PCB; solder paste, which was previously applied to the pads, holds the components in place temporarily; if surface-mount components are applied to both sides of the board, the bottom-side components are glued to the board. In both through hole and surface mount, the components are then soldered; once cooled and solidified, the solder holds the components in place permanently and electrically connects them to the board.
There are a variety of soldering techniques used to attach components to a PCB. High volume production is usually done with a pick-and-place machine and bulk wave soldering for through-hole parts or reflow ovens for SMT components or through-hole parts, but skilled technicians are able to hand-solder very tiny parts (for instance 0201 packages which are 0.02 in. by 0.01 in.) under a microscope, using tweezers and a fine-tip soldering iron, for small volume prototypes. Selective soldering may be used for delicate parts. Some SMT parts cannot be soldered by hand, such as ball grid array (BGA) packages. All through-hole components can be hand soldered, making them favored for prototyping where size, weight, and the use of the exact components that would be used in high volume production are not concerns.
Often, through-hole and surface-mount construction must be combined in a single assembly because some required components are available only in surface-mount packages, while others are available only in through-hole packages. Or, even if all components are available in through-hole packages, it might be desired to take advantage of the size, weight, and cost reductions obtainable by using some available surface-mount devices. Another reason to use both methods is that through-hole mounting can provide needed strength for components likely to endure physical stress (such as connectors that are frequently mated and demated or that connect to cables expected to impart substantial stress to the PCB-and-connector interface), while components that are expected to go untouched will take up less space using surface-mount techniques. For further comparison, see the SMT page.
After the board has been populated it may be tested in a variety of ways:
While the power is off, visual inspection, automated optical inspection. JEDEC guidelines for PCB component placement, soldering, and inspection are commonly used to maintain quality control in this stage of PCB manufacturing.
While the power is off, analog signature analysis, power-off testing.
While the power is on, in-circuit test, where physical measurements (for example, voltage) can be done.
While the power is on, functional test, just checking if the PCB does what it had been designed to do.
To facilitate these tests, PCBs may be designed with extra pads to make temporary connections. Sometimes these pads must be isolated with resistors. The in-circuit test may also exercise boundary scan test features of some components. In-circuit test systems may also be used to program nonvolatile memory components on the board.
In boundary scan testing, test circuits integrated into various ICs on the board form temporary connections between the PCB traces to test that the ICs are mounted correctly. Boundary scan testing requires that all the ICs to be tested use a standard test configuration procedure, the most common one being the Joint Test Action Group (JTAG) standard. The JTAG test architecture provides a means to test interconnects between integrated circuits on a board without using physical test probes, by using circuitry in the ICs to employ the IC pins themselves as test probes. JTAG tool vendors provide various types of stimuli and sophisticated algorithms, not only to detect the failing nets, but also to isolate the faults to specific nets, devices, and pins.
When boards fail the test, technicians may desolder and replace failed components, a task known as rework.
Protection and packaging
PCBs intended for extreme environments often have a conformal coating, which is applied by dipping or spraying after the components have been soldered. The coat prevents corrosion and leakage currents or shorting due to condensation. The earliest conformal coats were wax; modern conformal coats are usually dips of dilute solutions of silicone rubber, polyurethane, acrylic, or epoxy. Another technique for applying a conformal coating is for plastic to be sputtered onto the PCB in a vacuum chamber. The chief disadvantage of conformal coatings is that servicing of the board is rendered extremely difficult.
Many assembled PCBs are static sensitive, and therefore they must be placed in antistatic bags during transport. When handling these boards, the user must be grounded (earthed). Improper handling techniques might transmit an accumulated static charge through the board, damaging or destroying components. The damage might not immediately affect function but might lead to early failure later on, cause intermittent operating faults, or cause a narrowing of the range of environmental and electrical conditions under which the board functions properly.
See also
Reference list
Electronics manufacturing
Printed circuit board manufacturing | Printed circuit board manufacturing | [
"Engineering"
] | 5,225 | [
"Electrical engineering",
"Electronic engineering",
"Electronics manufacturing",
"Printed circuit board manufacturing"
] |
75,675,923 | https://en.wikipedia.org/wiki/Back%20Cove%20South%20Storage%20Facility | The Back Cove South Storage Facility will be the result of a large construction project begun in 2020 in the Back Cove neighborhood of Portland, Maine. Centered on Back Cove Park, between Preble Street to the southwest, Franklin Street to the northeast and Interstate 295 to the southeast, the project—a combined sewer and stormwater overflow (or CSO)—is estimated to cost $40 million, and is the city's largest such project to date. It is designed to reduce combined sewage overflow into both Back Cove and Portland's harbor by 40%. Currently, after heavy rainfall, storm water mixes with sewage and discharges into Casco Bay.
Four concrete tanks, with a total capacity of 3.5 million gallons, will be installed below ground. The soil removed from Back Cove Park will be used to raise the area's elevation, and the soccer fields and access to the Back Cove Trail—which were both demolished as part of the construction—will be restored.
The Back Cove West Storage Conduit, which was installed beside Baxter Boulevard on the western side of Back Cove, was also part of the project, which is being undertaken by Sargent. The final piece of box conduit was installed in October 2022.
The South Storage Facility is Portland's third storage conduit installed at Back Cove. In 2013, the city had built two conduits, each capable of capturing one million gallons of sewer and stormwater to prevent overflow from entering the cove. These were installed in Payson Park and under Baxter Boulevard. A fourth project, to include a 2.25-million-gallon storage conduit is also planned.
The project's completion date was extended by two years to the summer of 2025 due to the discovery of soft clay. It will also cost around $1 million more than originally expected.
Functionality
The underground storage tank will collect the first flow of stormwater—the equivalent of of rainfall containing the highest concentration of pollution—during heavy rainfalls and raw sewage from three of the city’s CSOs and store it until it can be pumped to the East End Treatment Plant, located around to the northeast, beside Tukey's Bridge. The contaminants will then be removed and treated before the water is discharged into Back Cove.
Funding
The project is being funded through wastewater fees, which are tied to water usage by homeowners and businesses. "None of this is tax base," said senior engineer Bradley Roland. "It's paid for every time someone flushes the toilet."
See also
2024 Portland flood
References
External links
"Portland Back Cove South Storage Conduit Project" – Sebago Technics, YouTube, 2020
Combined Sewer Overflows (CSOs) – Environmental Protection Agency
Industrial buildings and structures in Portland, Maine
Stormwater management
2020 establishments in Maine | Back Cove South Storage Facility | [
"Chemistry",
"Environmental_science"
] | 576 | [
"Water treatment",
"Stormwater management",
"Water pollution"
] |
68,460,121 | https://en.wikipedia.org/wiki/Nicotyrine | Nicotryine is lesser known and minor tobacco alkaloid. It inhibits metabolism of nicotine through CYP2A6 enzyme inhibition (Ki = 7.5 ± 2.9). It also inhibits CYP2A13 (Ki = 5.6 ± 0.86) which might play role in nicotine metabolism. Nicotyrine is formed by gradual oxidation of nicotine in e-liquids and causes delayed nicotine clearance and attenuated withdrawal symptoms.
It has insecticidal properties like nicotine and certain derivatives have been synthesized for that property.
Chemistry
alpha-nicotyrine and beta-nicotyrine are positional isomers of each other.
Synthesis
Nicotyrine can be produced readily from nicotine by catalytic dehydrogenation and from tobacco biomass by catalytic pyrolysis.
See also
Myosmine
References
Pyridine alkaloids
Pyrroles
3-Pyridyl compounds | Nicotyrine | [
"Chemistry"
] | 192 | [
"Pyridine alkaloids",
"Alkaloids by chemical classification"
] |
68,462,656 | https://en.wikipedia.org/wiki/Landsupport | Landsupport (spelling: LANDSUPPORT) is a pilot consulting project funded by the European Union for land use for the near-natural modeling of different types and methods of land use while at the same time protecting the environment.
Project goal
In the long term, sustainable use of the soil must be guaranteed in order to meet the needs of the world's population. The project brings together numerous universities, research institutions, companies and stakeholders with the aim of creating a web-based, free system to support practical agriculture and land users in making decisions about sustainable land use, environmental protection and agricultural use.
With the active participation of various and numerous stakeholders in and outside Europe, the consortium also aims at legislation at European level, based on scientific data that is processed and modeled in the system.
In the research framework program Horizon 2020, the project is organized under the direction of Fabio Terribile at the University of Naples Federico II.
Project consortium
The Landsupport consortium consists of the following partners:
University of Naples, Italy
ARIESPACE, Italy
Barcelona Supercomputing Center, Spain
University of Natural Resources and Life Sciences, Vienna, Austria
Consiglio Nazionale delle Ricerche, Italy
Crops for the Future, Malaysia
ICARDA, Tunisia
Institute of Advanced Studies, Hungary
Institute for Environmental Protection and Research, Italy
Rasdaman GmbH, Germany
Joint Research Center, European Commission
Regione Campania, Italy
University of Milan, Italy
Zala County, Hungary
CMAST / Modis, Belgium
Acteon, France
Federal Environment Agency, Austria
Slovenian Forestry Institute, Slovenia
Results and advice
The results of the investigations are internationally evaluated by the members in specialist committees and made available to practice and the responsible bodies at regional and state level, as well as to the European Uninion for legislative and approval procedures.
See also
Bioeconomy
Biofector
Edaphon
Microbiology
Pedology
External links
Webpage Landsupport
Report of EU concerning Landsupport
Balkan green Deal BW
BeyondSoil Initiative of the University Hohenheim
Greenerde.eu
Scoalaagricola.eu
Danube Strategy Baden-Württemberg
Green Deal and Biodiversity in Europe
References
Agroecology
Agronomy
Botany
.
Biology and pharmacology of chemical elements
.
Ecology
Ecological economics
Edaphology
Fertilizers
Organic fertilizers
Organic food
Recycling
Soil
Soil improvers
Sustainable agriculture
Sustainable gardening
Sustainable technologies
Systems ecology
Waste management | Landsupport | [
"Chemistry",
"Biology",
"Environmental_science"
] | 483 | [
"Pharmacology",
"Fertilizers",
"Properties of chemical elements",
"Plants",
"Systems ecology",
"Biology and pharmacology of chemical elements",
"Ecology",
"Soil chemistry",
"Botany",
"Biochemistry",
"Environmental social science"
] |
68,465,122 | https://en.wikipedia.org/wiki/Journal%20of%20Soft%20Computing%20in%20Civil%20Engineering | The Journal of Soft Computing in Civil Engineering is a quarterly peer-reviewed open-access scientific journal covering soft computing applications in civil engineering. It was established in 2017 and is a member of the Committee on Publication Ethics. The editor-in-chief is Hosein Naderpour. The journal is indexed and abstracted in Scopus.
References
External links
Academic journals established in 2017
Quarterly journals
Creative Commons Attribution-licensed journals
Civil engineering journals
English-language journals
Computer science journals | Journal of Soft Computing in Civil Engineering | [
"Engineering"
] | 97 | [
"Civil engineering journals",
"Civil engineering"
] |
68,465,275 | https://en.wikipedia.org/wiki/Shirley%20Chiang | Shirley Chiang is an American microscopist focused on the high-resolution imaging of surfaces, including the use of scanning tunneling microscopy and low-energy electron microscopy, and known for capturing the first image showing the ring structure of benzene molecules. She is a professor at the University of California, Davis, in the Department of Physics and Astronomy, and editor-in-chief of the MDPI journal Nanomaterials.
Education and career
Chiang graduated from Harvard University in 1976, and earned her Ph.D. at the University of California, Berkeley in 1983. She became a researcher for IBM Research in their Almaden Research Center in San Jose, California from 1983 until 1994. It was at IBM, in 1988, that she captured the first image of individual benzene molecules, using a scanning tunneling microscope to view benzene attached in a single-molecule-thick layer to a rhodium crystal.
In 1994, she took her present position at the University of California, Davis. She was department chair from 2003 to 2008, and has also served as a faculty assistant to the vice provost for academic affairs.
Recognition
Chiang was named a Fellow of the American Physical Society (APS) in 1994, after a nomination from the APS Division of Chemical Physics, "for advances in real space imaging of surface structure by scanning tunneling and force microscopies, especially molecular identification, imaging of metals and alloys, and atomic-scale frictional forces". She became a fellow of the American Vacuum Society in 2006, and a fellow of the American Association for the Advancement of Science in 2008.
She was a 2001 winner of the UC Davis Academic Senate Distinguished Teaching Award.
References
External links
Home page
Year of birth missing (living people)
Living people
American physicists
American women physicists
Microscopists
Harvard University alumni
University of California, Berkeley alumni
University of California, Davis faculty
Fellows of the American Physical Society
21st-century American women | Shirley Chiang | [
"Chemistry"
] | 389 | [
"Microscopists",
"Microscopy"
] |
68,465,282 | https://en.wikipedia.org/wiki/Charopinesta%20suavis | Charopinesta suavis, also known as the sweet pinhead snail, is a species of land snail that is endemic to Australia's Lord Howe Island in the Tasman Sea.
Description
The depressedly turbinate shell of the mature snail is 1.4 mm in height, with a diameter of 2.6 mm, and a low, stepped spire. It is golden amber in colour. The whorls are slightly rounded, with impressed sutures and fine, very closely spaced radial ribs. It has a roundedly lunate aperture and moderately widely open umbilicus.
Distribution and habitat
This extremely rare snail is only been recorded by a single shell collected from the summit of Mount Lidgbird and may be extinct.
References
suavis
Gastropods of Lord Howe Island
Taxa named by Tom Iredale
Gastropods described in 1944
Species known from a single specimen | Charopinesta suavis | [
"Biology"
] | 177 | [
"Individual organisms",
"Species known from a single specimen"
] |
68,466,234 | https://en.wikipedia.org/wiki/SLAC%20Theory%20Group | The SLAC Theory Group is the hub of theoretical particle physics research at the SLAC National Accelerator Laboratory at Stanford University. It is a subdivision of the Elementary Particle Physics (EPP) Division at SLAC.
Research
The group has a diverse research program, specializing in areas of quantum field theory, beyond the standard model physics, dark matter, neutrinos, and collider phenomenology.
Members
The group is currently led by 9 faculty members, and has a dozen postdoctoral researchers and students at any given time.
Notable physicists who were students or postdoctoral researchers in the SLAC Theory Group include Nima Arkani-Hamed, Thomas Appelquist, Mirjam Cvetic, Michael Dine, John Ellis, Rouven Essig, Edward Farhi, Steven Frautschi, Joshua Frieman, Roscoe Giles, Yuval Grossman, Jack F. Gunion, Alan Guth, Howard Haber, Claude Itzykson, Robert Jaffe, David E. Kaplan, Igor Klebanov, Peter Lepage, Christopher Llewellyn Smith, Kirill Melnikov, Stephen Parke, Maxim Perelstein, Joel Primack, Joseph Polchinski, Davison Soper, Henry Tye, Mark Wise, and Tung-Mow Yan.
Past and present members of the SLAC Theory Group have received a total of at least 3 Breakthrough in Fundamental Physics Prizes ($3 million USD prize), 10 Sakurai Prizes ($10,000 USD), 5 Dirac Medals ($5,000 USD), 4 New Horizons in Physics Prizes ($100,000 USD), and 2 Gribov Medals ($5,000 USD).
Faculty
Current and former faculty members in the SLAC Theory Group include:
James Bjorken, discoverer of Bjorken Scaling (light-cone scaling) and Bjorken Sum Rule, 2004 Dirac Medal recipient
Stanley Brodsky, 2007 Sakurai Prize recipient for applications of perturbative quantum field theory to the analysis of hard exclusive strong interaction processes
Lance Dixon, pioneer of new methods to calculate Feynman diagrams in quantum chromodynamics and other Yang–Mills theories; 2014 recipient of the Sakurai Prize and 2023 recipient of the Galileo Medal
Sidney Drell, known for his contributions to quantum electrodynamics, including the Drell-Yan process, 2011 National Medal of Science recipient
Alexander Friedland, neutrino physicist
JoAnne Hewett, associate lab director of the Fundamental Physics Directorate and the chief research officer at SLAC
Stefan Hoeche, known for SHERPA parton shower event-generator framework
Shamit Kachru, pioneer of string theory
Rebecca Leane, astroparticle physicist
Bernhard Mistlberger, pioneer of multi-loop Higgs calculations at hadron colliders and 2021 Gribov Medal recipient
Pierre Noyes, known for theoretical work on the quantum mechanical three-body problem for strongly interacting particles
Jogesh Pati, known for the Pati-Salam model, 2000 Dirac Medal recipient
Michael Peskin, known for the Peskin–Takeuchi parameter, and his popular Quantum Field Theory textbook with Daniel Schroeder
Helen Quinn, known for Peccei–Quinn theory which earned her the 2010 Dirac Medal and the 2014 Sakurai Prize
Thomas Rizzo, Theory Group leader
Philip Schuster, 2015 New Horizons in Physics Prize recipient, known for new experimental searches for dark sectors using high-intensity electron beams
Eva Silverstein, known for work on early universe cosmology and string theory, recipient of 1999 MacArthur "Genius grant" award
Natalia Toro, 2015 New Horizons in Physics Prize recipient, known for new experimental searches for dark sectors using high-intensity electron beams
Jay Wacker, particle phenomenologist
References
Theoretical physics institutes | SLAC Theory Group | [
"Physics"
] | 775 | [
"Theoretical physics",
"Theoretical physics institutes"
] |
68,466,273 | https://en.wikipedia.org/wiki/Transport%20and%20bus%20boycotts%20in%20the%20United%20States | Transport and bus boycotts in the United States were protests against the racial segregation of transport services. These occurred before the passage of the 1964 Civil Rights Act, which outlawed such forms of discrimination.
Frederick Douglass and James N. Buffum
In 1841, abolitionist Frederick Douglass and his friend James N. Buffum entered a train car reserved for white passengers in Lynn, Massachusetts. When the conductor ordered them to leave the car, they refused, after which they were forcefully removed.
Elizabeth Jennings Graham
On July 16, 1854, 24-year-old schoolteacher Elizabeth Jennings Graham was forcefully expelled by a train conductor after boarding a streetcar without a “Colored Persons Allowed” sign.
Charlotte L. Brown
In the mid-19th century, San Francisco's horse-drawn streetcar companies only accepted white passengers. On April 17, 1863, schoolteacher Charlotte L. Brown boarded an Omnibus Railroad Company streetcar, when she was approached by the conductor and asked to leave the car. After she objected, he forcefully removed her.
Katherine "Kate" Brown
Katherine Brown boarded a train in Alexandria, Virginia, when traveling towards Washington, D.C., on February 8, 1868. She entered "what they call the 'white people's car.'" As she was boarding, a railroad policeman told her to move to a different car. He told her the car she had entered "was for ladies," and "no damned nigger was allowed to ride in that car; never was and never would be." She replied, "This car will do." Following this, the policeman and another employee grabbed Brown and began beating and kicking her. The men threw and dragged her on the boarding platform, threatening to arrest her. After a violent struggle that lasted six minutes, she asked, "What are you going to arrest me for? What have I done? Have I committed robbery? Have I murdered anybody?" Brown's injuries were so severe she was bedridden for several weeks and coughed blood.
Senators Charles Sumner and Justin Morrill called for a formal investigation, and Senator Charles Drake agreed. A resolution was passed on February 10, and the Senate committee heard testimony later that month. Brown sued the railway company for damages and was awarded $1,500 in damages in the district court. The railway company appealed, and the case eventually went before the US Supreme Court. On November 17, 1873, in an opinion delivered by Justice David Davis, the Court held that racial segregation on the railroad line was not allowed under its Congressional charter, which stated "no person shall be excluded from the cars on account of race." Davis dismissed the company's "separate but equal" argument as "an ingenious attempt to evade a compliance with the obvious meaning of the requirement" of the 1863 charter, and decided in favor of Brown.
The Court held that white and black passengers must be treated with equality in the use of the railroad's cars:
Civil Rights Act of 1875
United States Senator Charles Sumner, with the assistance of John Mercer Langston, drafted in 1870 the bill that would become the Civil Rights Act of 1875. The bill was proposed by Senator Sumner and co-sponsored by Representative Benjamin F. Butler, both Republicans from Massachusetts, in the 41st Congress of the United States in 1870. Congress removed the coverage of public schools that Sumner had included. The act was passed by the 43rd Congress in February 1875 as a memorial to honor Sumner, who had recently died. It was signed into law by United States President Ulysses S. Grant on March 1, 1875.
Robert and Samuel Fox
Robert Fox, an African American activist, sparked a civil rights battle in Louisville, Kentucky, in October 1870 by entering a segregated streetcar. Fox got in a streetcar with his brother and business partner Samuel alongside their employee, Horace Pearce. They paid their fares and sat down in the white section of the car, in violation of local laws prohibiting black men from riding inside the trolley cars (black women were permitted to ride at the back of the car, but black men were usually only allowed to ride on the platform with the driver or not at all). When John Russell, a white passenger, complained, the driver asked the men to leave. The black passengers refused. Other drivers were called to the scene, and the men were beaten and thrown off the car. In response, a crowd of African Americans gathered outside and began to throw dirt clods and rocks at the streetcar, insisting that the men be allowed to ride. The Fox brothers and Pearce returned to the streetcar and again took seats in the 'white' section, this time holding rocks in their hands to protect themselves. The three men were arrested and charged with disorderly conduct. At their trial, the defendants were unable to testify because the judge forbade blacks from testifying against whites. They were found guilty and fined $5 each ($99.48 in today's money (2021)) Shortly after, Fox filed a charge of assault and battery against the streetcar company in federal court, claiming that separate seating policies based on race were unlawful and the driver's actions were therefore improper. A jury found the company rules to be invalid and awarded damages of $15 to Fox and his fellow riders.
The company defied the jury's finding and continued racially segregated seating. As a result, Louisville black leaders organized "ride-ins" all over the city. Streetcar after streetcar was boarded by African Americans who took seats in the white section. The drivers, in response, left the cars entirely. On several occasions, black passengers drove the cars themselves, to the cheers of black spectators. Gangs of white youths swarmed into the cars, throwing black riders off them. One incident involved an African American youth named Carey Duncan. At 7 P.M. on May 12, he boarded a streetcar, walked past the driver, and sat down among the white passengers. The driver, following the company directive, did not attempt to throw him off. Instead, he stopped the car, lit a cigar, and refused to proceed until the black youth left the white area. The governor, the Louisville chief of police, and other prominent citizens looked on from the sidewalks while a large crowd gathered around the streetcar and began to shout at the youth: "Put him out!" "Hit him!" "Kick him!" "Hang him!". Some of them climbed into the car, yelling insults. Carey Duncan quietly refused to move. The crowd dragged him from his seat, pulled his inert body off the car, and began to beat him. When Duncan started to defend himself, the city police intervened.
Duncan was charged with disorderly conduct. His trial was held in Louisville city court and he was fined. The judge delivered a warning to Louisville blacks that further ride-ins would be punished. Louisville newspapers responded by blaming African Americans for the troubles and urging them to stop the ride-ins. "The assumption of their right to ride in the street cars, under the present circumstances, is injudicious, and we hope will not be persisted in," wrote an editor of the Daily Commercial. "To do so may lead to serious trouble." Finally, Mayor John G. Baxter announced he would meet with interested parties on both sides to attempt a settlement.
At the meeting, the streetcar companies finally capitulated, realizing that the federal government was likely to step in and enforce integration if they didn't agree to it themselves. To "avoid serious collisions," the company announced it would allow all passengers to choose their own seating. Afterward, mixed seating became a common practice. Newspapers around the country commented on the demonstrations and their outcome.
Ida B. Wells
On May 4, 1884, a train conductor with the Chesapeake and Ohio Railway ordered Ida B. Wells to give up her seat in the first-class ladies' car and move to the smoking car, which was already crowded with other passengers. The previous year, the Supreme Court had ruled against the federal Civil Rights Act of 1875 (which had banned racial discrimination in public accommodations). This verdict supported railroad companies that chose to racially segregate their passengers. When Wells refused to give up her seat, the conductor and two men dragged her out of the car. Wells gained publicity in Memphis when she wrote a newspaper article for The Living Way, a Black church weekly, about her treatment on the train. In Memphis, she hired an African American attorney to sue the railroad. When her lawyer was bribed and paid off by the railroad company, she hired a White attorney. She won her case on December 24, 1884, when the local circuit court granted her a $500 award. The railroad company appealed to the Tennessee Supreme Court, which reversed the lower court's ruling in 1887. It concluded: "We think it is evident that the purpose of the defendant in error was to harass with a view to this suit, and that her persistence was not in good faith to obtain a comfortable seat for the short ride." Wells was ordered to pay court costs. Her reaction to the higher court's decision revealed her strong convictions on civil rights and religious faith, as she responded: "I felt so disappointed because I had hoped such great things from my suit for my people. ... O God, is there no ... justice in this land for us?"
Plessy v. Ferguson
Homer Plessy On June 7, 1892, Plessy bought a first-class ticket at the Press Street Depot and boarded a "Whites Only" car of the East Louisiana Railroad in New Orleans, Louisiana, bound for Covington, Louisiana. The action violated Louisiana's Separate Car Act of 1890, that law required black passengers to be seated in separate passenger cars on Louisiana railroads from white travelers.
Plessy was charged with boarding a "whites-only" car. Plessy pleaded not guilty, contending the law was unconstitutional. He was convicted at the district level. Plessy appealed his case, but the conviction was sustained by the Louisiana Supreme Court. Plessy then appealed to the only court capable of overriding his state's decision, the U.S. Supreme Court. In May 1896, the Supreme Court issued a 7–1 decision against Plessy, ruling that the Louisiana law did not violate the Fourteenth Amendment to the U.S. Constitution and stating that although the Fourteenth Amendment established the legal equality of whites and blacks it did not and could not require the elimination of all "distinctions based upon color". The Court rejected Plessy's arguments that the Louisiana law inherently implied that black people were inferior. The court ushered in racial segregation in the United States by giving states the power to enact criminal statutes that separated black people from society. Segregation impacted the lives of millions of African Americans as they were barred from restaurants, hospitals, hotels, housing, schools, job prospects, and interpersonal relationships because of their skin color. Justice John Marshall Harlan was the only justice who contradicted the Court's decision. Harlan, now known as the "Great Dissenter", wrote, "the Constitution is color-blind, and neither knows nor tolerates classes among citizens", and so the law's distinguishing of passengers' races should have been found unconstitutional.
Baton Rouge bus boycott
The Baton Rouge bus boycott was a boycott of city buses launched on June 19, 1953, by African American residents of Baton Rouge, Louisiana, who were seeking integration into the system. In the early 1950s, they made up about 80% of the ridership of the city buses and were estimated to account for slightly more than 10,000 passengers based on the $1,600 in daily revenue lost to the boycott and the fare that had recently increased to 15 cents. Under Jim Crow rules, black people were forced to sit in the back of the bus, even when the front of the bus was empty. State laws prohibited black citizens from owning private buses outside the city systems.
Montgomery bus boycott
The Montgomery bus boycott was a political and social protest campaign against the policy of racial segregation on the public transit system of Montgomery, Alabama. It was a foundational event in the civil rights movement in the United States.
The campaign lasted from December 5, 1955—the Monday after Rosa Parks, an African American woman, was arrested for not giving her seat to a white person—to December 20, 1956. That day was when the federal ruling Browder v. Gayle took effect, which led to a United States Supreme Court decision that declared the Alabama and Montgomery laws that segregated buses were unconstitutional.
Tallahassee bus boycott
The Tallahassee bus boycott was a citywide boycott in Tallahassee, Florida that sought to end racial segregation in the employment and seating arrangements of city buses. On May 26, 1956, Wilhelmina Jakes and Carrie Patterson, two Florida A&M University students, were arrested by the Tallahassee Police Department for "placing themselves in a position to incite a riot".
Robert Saunders, representing the NAACP, and Rev. C. K. Steele began talks with city authorities while the local African American community started boycotting the city's buses. The Inter-Civic Council ended the boycott on December 22, 1956. On January 7, 1957, the City Commission repealed the bus-franchise segregation clause because of the United States Supreme Court ruling Browder v. Gayle (1956).
Civil Rights Act of 1964
The Civil Rights Act of 1964 () outlaws discrimination based on race, color, religion, sex, national origin, and later sexual orientation and gender identity.
The legislation had been proposed by President John F. Kennedy in June 1963, but it was opposed by filibuster in the Senate. After Kennedy was assassinated on November 22, 1963, President Lyndon B. Johnson pushed the bill forward. The United States House of Representatives passed the bill on February 10, 1964, and after a 54-day filibuster, it passed the United States Senate on June 19, 1964. The final vote was 290–130 in the House of Representatives and 73–27 in the Senate. After the House agreed to a subsequent Senate amendment, the Civil Rights Act was signed into law by President Johnson at the White House on July 2, 1964.
The Title II of the law Outlawed discrimination based on race, color, religion, or national origin in hotels, motels, restaurants, theaters, and all other public accommodations engaged in interstate commerce; exempted private clubs without defining the term "private". Title III Prohibited state and municipal governments from denying access to public facilities on grounds of race, color, religion, or national origin. Title IV—desegregation of public education enforced the desegregation of public schools and authorized the U.S. Attorney General to file suits to enforce the act.
See also
History of civil rights in the United States
References
Civil rights movement protests
Public transportation in the United States
Boycotts | Transport and bus boycotts in the United States | [
"Physics"
] | 3,011 | [
"Physical systems",
"Transport",
"Transport activism"
] |
68,466,796 | https://en.wikipedia.org/wiki/Rat%20Rock%20%28Morningside%20Heights%29 | Rat Rock is an outcrop of Manhattan schist between 600 and 604 West 114th Street in the Morningside Heights neighborhood of Manhattan, New York City. The boulder measures approximately high and long; it is notable as one of the only remaining such rocks remaining in Manhattan's street grid. It was named Rat Rock for the large number of rats nesting in it, similar to the other Rat Rock in Central Park. The row houses around it were built in the 1890s, when land in Manhattan was significantly less valuable. Though the land on which it sits has greatly appreciated in value, Columbia University, which owns Rat Rock along with most of West 114th Street, has no plans to remove it, as it has been estimated that removing the rock could cost hundreds of thousands of dollars. The fence around it was placed by the university in order to prevent vandalism. Columbia professor Andrew Dolkart described it as "an extraordinary survivor" of New York City's development, because it "hints at the geology of the city", and The New York Times labelled it one of New York's "most amazing natural wonders".
References
Columbia University campus
Stones
Morningside Heights, Manhattan | Rat Rock (Morningside Heights) | [
"Physics"
] | 242 | [
"Stones",
"Physical objects",
"Matter"
] |
68,467,251 | https://en.wikipedia.org/wiki/Xywav | Xywav is a medication used to treat cataplexy or excessive daytime sleepiness. It contains a mixture of the oxybate salts calcium oxybate, magnesium oxybate, potassium oxybate, and sodium oxybate. It is a central nervous system (CNS) depressant and it is taken by mouth.
Manufactured by the Jazz Pharmaceuticals company, it was approved for medical use in the United States in July 2020.
Medical uses
Xywav is indicated for the treatment of cataplexy or excessive daytime sleepiness in people aged seven years of age and older with narcolepsy; and for idiopathic hypersomnia.
Side effects
The US Food and Drug Administration (FDA) label for Xywav contains a boxed warning for central nervous system depression, abuse, and misuse.
Breathing problems
Slowed breathing, trouble breathing, sleep apnea.
Mental health problems
Confusion, hallucination, unusual or disturbing thoughts (abnormal thinking), anxiety, depression, suicidal thoughts or actions, increased tiredness, feelings of guilt or worthlessness, and difficulty concentrating.
Other
Sleepwalking.
Society and culture
Legal status
The sodium oxybate component of Xywav was granted orphan drug designation in November 1994 by the FDA. Xywav is a prescription drug and a Schedule III controlled substance in the United States.
Other names
In the testing phase of the drug, it was known as JZP-258.
Calcium, magnesium, potassium, and sodium oxybate is another name for gamma hydroxybutyrate (GHB).
References
Narcolepsy
Organic sodium salts
Orphan drugs
Treatment of sleep disorders | Xywav | [
"Chemistry"
] | 339 | [
"Organic sodium salts",
"Salts"
] |
68,468,604 | https://en.wikipedia.org/wiki/Platinum%E2%80%93samarium | Platinum-samarium is a binary inorganic compound of platinum and samarium with the chemical formula PtSm. This intermetallic compound forms crystals.
Synthesis
Fusion of stoichiometric amounts of pure substances:
Physical properties
Platinum-samarium forms crystals of rhombic crystal system, space group P nma, cell parameters a = 0.7148 nm, b = 0.4501 nm, c = 0.5638 nm, Z = 4, structure similar to that of iron boride (FeB).
The compound melts congruently at a temperature of ≈1810 °C.
References
Samarium compounds
Platinum compounds
Inorganic compounds
Intermetallics | Platinum–samarium | [
"Physics",
"Chemistry",
"Materials_science"
] | 135 | [
"Inorganic compounds",
"Metallurgy",
"Intermetallics",
"Condensed matter physics",
"Alloys"
] |
68,469,340 | https://en.wikipedia.org/wiki/Zhangpeishanite | Zhangpeishanite is a mineral named after Zhang Peishan (Chinese: 张培善), a Chinese mineralogist at the Institute of Geology of the Chinese Academy of Sciences, in recognition of his contributions to studying the mineralogy Bayan Obo deposit, where the mineral is mined. The Bayan Obo deposit is also known for being a world class deposit. The mineral got approved by the IMA in 2006 but was published two years after its approval. The mineral consists of barium chloride fluoride.
Properties
Some of the datas collected about zhangpeishanite were carried out on a synthetic equivalent of the mineral, such as cleavage and refractive index, due to zhangpeishanite's minute grain size. The mineral is isostructural with matlockite. It is a member of the matlockite group, and it is the barium dominant analogue of rorisite and matlockite. It is associated with barite, hematite, norsethite and fluorite. The inclusions form as bands within fluorite. The mineral occurs in fluorite as inclusions, up to 100 μm. However, they are typically much smaller, about 50 μm. It consists of barium mostly (71.21%), chlorine (18.94%) and fluorine (9.85%). Singular crystals can be obtained at 1500 K by solid-state reaction between BaF2 and BaCl2.
References
Barium minerals
Chlorides
Fluorides
Tetragonal minerals | Zhangpeishanite | [
"Chemistry"
] | 321 | [
"Fluorides",
"Chlorides",
"Inorganic compounds",
"Salts"
] |
68,469,876 | https://en.wikipedia.org/wiki/Infrastructure%20bond | Infrastructure bond is a type of bond issued either by private corporations or by state-owned enterprises to finance the construction of an infrastructure facilities such as highways, ports, railways, airport terminals, bridges, tunnels, pipelines, etc. These bonds may be nominated both in local and in more stable foreign currencies, such as U.S. dollars or euros. Infrastructure bonds are popular in developing economies where there is a strong demand for infrastructure.
Operation
As a rule, the issuer of such securities, after the construction of an infrastructure facility is completed, receives it on a concession for some time (most often several decades) and collects the payments from the facility users (for example, a toll road). Quite often, the state (or several states), on the territory of which this object is being built, provides guarantees for the issued bonds, which makes them attractive to a larger number of market participants, as doing so reduces the risk. Due to the long payback period of infrastructure facilities, the bond circulation period is also quite long (often several decades); therefore, such bonds will mostly target institutional investors including insurance companies and pension funds. To make such bond even more attractive, the state authorities may arrange certain interest and tax benefits.
See also
Build–operate–transfer
Infrastructure-based development
Infrastructure and economics
Public–private partnership
References
International finance
Infrastructure | Infrastructure bond | [
"Engineering"
] | 274 | [
"Construction",
"Infrastructure"
] |
68,470,612 | https://en.wikipedia.org/wiki/A572%20steel | ASTM A572 steel is a common high strength, low alloy (HSLA) structural steel used in the United States. A572 steel properties are specified by ASTM International standards.
Grades
A572 steel has five different grades: 42, 50, 55, 60 and 65. Each of these grades differ in their mechanical properties and chemical composition.
Chemical Composition
Material Properties
Forms
A572 steel is produced in a variety of different steel forms, which include:
Plates
Bars
Structural Shapes
Channels
I-Beams
Angles
Wide Flange Beams
Sheet Piling
Applications
A572 steel is typically used in structural applications due to its high strength, ductility, weldability and corrosion resistance. These applications include structural sections, reinforcing bars, bridges, skyscrapers and houses.
References
Structural steel
Metals | A572 steel | [
"Chemistry",
"Engineering"
] | 161 | [
"Structural engineering",
"Metals",
"Structural steel"
] |
68,470,706 | https://en.wikipedia.org/wiki/Hack%20computer | The Hack Computer is a theoretical computer design created by Noam Nisan and Shimon Schocken and described in their book, The Elements of Computing Systems: Building a Modern Computer from First Principles. In using the term “modern”, the authors refer to a digital, binary machine that is patterned according to the von Neumann architecture model.
The Hack computer is intended for hands-on virtual construction in a hardware simulator application as a part of a basic, but comprehensive, course in computer organization and architecture. One such course, created by the authors and delivered in two parts, is freely available as a massive open online course (MOOC) called Build a Modern Computer From First Principles: From Nand to Tetris. In the twelve projects included in the course, learners start with a two input Nand gate and end up with a fully operational virtual computer, including both hardware (memory and CPU) and software (assembler, VM, Java-like programming language, and OS). In addition to the hardware simulator used for initial implementation of the computer hardware, a complete Hack computer emulator program and assembler that supports the projects described in the book and the on-line course is also available at the author's web site.
Hardware architecture
The Hack computer hardware consists of three basic elements as shown in the block diagram. There are two separate 16-bit memory units and a central processing unit (CPU). Because data is moved and processed by the computer in 16-bit words, the Hack computer is classified as a 16-bit architecture.
The instruction memory, implemented as read-only memory from the viewpoint of the computer and designated ROM, holds assembled binary program code for execution. The random access memory, called RAM, provides storage for an executing program’s data and provides services and storage areas for the computer’s memory-mapped I/O mechanism. Data processing and program control management are provided by the CPU.
The three units are connected by parallel buses. The address buses (15-bit), as well as the data and instruction busses (16-bit) for the ROM and RAM units are completely independent. Therefore, the Hack design follows the Harvard architecture model with respect to bus communication between the memory units and the CPU. All memory is word addressable only.
Read-only memory (ROM)
The Hack computer’s ROM module is presented as a linear array of individually addressable, sequential, 16-bit memory registers. Addresses start at 0 (0x0000). Since the memory elements are sequential devices, a system clock signal is supplied by the simulation application and the computer emulator application. The ROM address bus is 15 bits wide, so a total of 32,768 individual words are available for program instructions. The address of the currently active word is supplied by a program counter register within the CPU (see below). The value in the ROM memory register identified by the address placed on the instruction address bus in a particular clock cycle is available as the "current" instruction at the beginning of the next cycle. There is no instruction register; instructions are decoded in each cycle from the currently active ROM register.
Random access memory (RAM)
Although the RAM module is also viewed as a continuous linear array of individually addressable sequential, read-write, 16-bit memory registers, it is functionally organized by address range into three segments. Addresses 0 (0x000) through 16383 (0x3FFF) contain conventional 16-bit, read-write registers and are meant for use as general-purpose program data storage.
The registers at addresses 16384 (0x4000) through 24575 (0x5FFF) are essentially like data RAM, but they are also designated for use by a built-in screen I/O subsystem. Data written to addresses in this range have the side effect of producing output on the computer’s virtual 256 x 512 screen (see I/O). If a program does not require screen output, registers in this range may be used for general program data.
The final address in the RAM address space, at 24576 (0x6000), contains a single one word register whose current value is controlled by the output of a keyboard attached to the computer hosting the Hack emulator program. This keyboard memory map register is read-only (see I/O).
Data memory addresses in the range 24577 (0x6001) through 32767 (0x7FFF) are invalid. State transitions of the selected RAM memory register is also coordinated by the system clock signal.
Central Processing Unit (CPU)
As illustrated in the accompanying diagram, the Hack computer central processing unit (CPU) is an integrated logic unit with internal structure. It provides many of the functions found in simple, commercially available CPUs. The most complex element of the CPU is the arithmetic logic unit (ALU) which provides the computational functionality of the computer. The ALU is a combinational logic device having two 16-bit input operands and a single 16-bit output. The computation produced as output from the operands is specified by a set of six ordered, single-bit inputs to the ALU. The ALU also emits two single-bit status flags which indicate whether a computation result is zero (zr flag) or negative (ng flag).
The CPU also contains two 16-bit registers, labeled D and A. The D (Data) register is a general-purpose register whose current value always supplies the ALU x operand, although for some instructions its value is ignored. While the A (Address) register may also provide its current value as the y operand to the ALU when so directed by an instruction, its value may also be used for data memory addressing and as a target address in instruction memory for branching instructions. To facilitate this function, the A register is directly associated with a "pseudo-register" designated as M which is not explicitly implemented in hardware. This M register therefore represents the value contained in RAM having the address of the current value contained in the A register.
The final important element in the CPU is the program counter (PC) register. The PC is a 16-bit binary counter whose low 15 bits specify the address in instruction memory of the next instruction for execution. Unless directed otherwise by a branching instruction, the PC increments its value at the end of each clock cycle. The CPU also includes logic to change, under program control, the order of the computer's instruction execution, by setting the PC to a non-sequential value. The PC also implements a single-bit reset input that initializes the PC value to 0 (0x0000) when it is cycled from logic 0 to logic 1 and back. Unlike many actual CPU designs, there is no program accessible hardware mechanism provided to implement CPU external or internal interrupts or support for function calls.
External Input and Output (I/O)
The Hack computer employs a memory-mapped approach to I/O. Bitmapped, black and white output to a virtual 256 x 512 screen is effected by writing a bitmap of the desired output to data memory locations 16384 (0x4000) through 24575 (0x5FFF). The data words in this address range are viewed as a linear array of bits with each bit value representing the black/white state of a single pixel on the computer emulator's virtual screen. The least significant bit of the word in the first memory address of the screen RAM segment sets the pixel in the upper left corner of the screen to white if it is 0 and black if it is 1. The next-most significant bit in the first word controls the next pixel to the right, and so on. After the first 512-pixel row is described by the first 32 words of screen memory, the mapping is continued in the same fashion for the second row with the next 32 words. Logic external to the computer reads the screen RAM memory map segment and updates the virtual screen.
If a keyboard is attached to the computer hosting the CPU emulator program, the emulator puts a 16-bit bit scan code corresponding to a key depressed during program execution into the keyboard register at RAM address 24576 (0x6000). If no key is depressed, this register contains the value 0. The emulator provides a toggle button to enable/disable the keyboard. The encoding scheme closely follows ASCII encoding for printable characters. The effect of the Shift key is generally honored. Codes are also provided for other keys often present on a standard PC keyboard; for example, direction control keys (←, ↑, ↓, →) and Fn keys.
Operating cycle
Step-wise operation of the CPU and memory units is controlled by a clock that is built-in to both the hardware simulator and the computer emulator programs. At the beginning of a clock cycle the instruction at the ROM address emitted by the current value of the program counter is decoded. The ALU operands specified in the instruction are marshalled where needed. The computation specified is performed by the ALU and the appropriate status flags are set. The computation result is saved as specified by the instruction. Finally, the program counter is updated to the value of the next required program instruction. If no branching was specified by the current instruction, the PC value is simply incremented. If branching was specified, the PC is loaded (from the A register) with the address of the next instruction to be executed. The cycle then repeats using the now current PC value.
Because of its Harvard memory architecture model, the Hack computer is designed to execute the current instruction and “fetch” the next instruction in a single, two-part clock cycle. The speed of the clock may be varied by a control element in both the hardware simulator and the CPU emulator. Independent of the selected speed however, each instruction is completely executed in one cycle. The user may also single-step through a program.
Execution of a program loaded in ROM is controlled by the CPU's reset bit. If the value of the reset bit is 0, execution proceeds according to the operating cycle described above. Setting the reset bit to 1 sets the PC to 0. Setting the reset bit value back to zero then begins execution of the current program at the first instruction; however, RAM contains the values from any previous activity on reset.
There is no hardware or machine language support for interrupts of any kind.
Data types
Values stored in ROM memory must represent valid Hack machine language instructions as described in the Instruction Set Architecture section.
Any 16-bit value may be stored in RAM. The data type of value stored in RAM is inferred by its location and/or its use within a program. The primary hardware supported data type is the 16-bit signed integer, which is represented in 2’s complement format. Signed integers therefore have the range -32768 through 32767. The lower 15 bits of a value in RAM may also represent an address in ROM or RAM in the sense of a pointer.
For values in the RAM memory registers assigned for screen I/O, the value will be interpreted as a 16 pixel map of the 256 row x 512 column virtual screen by the computer's independent I/O subsystem if the screen is "turned on".
The code value in keyboard memory may be read programmatically and interpreted for use by a program.
There is no hardware support for floating-point types.
Instruction set architecture (ISA) and machine language
The Hack computer's instruction set architecture (ISA) and derived machine language is sparse compared to many other architectures. Although the 6 bits used to specify a computation by the ALU could allow for 64 distinct instructions, only 18 are officially implemented in the Hack computer's ISA. Since the Hack computer hardware has direct support for neither integer multiplication (and division) or function calls, there are no corresponding machine language instructions in the ISA for these operations.
Hack machine language has only two types of instructions, each encoded in 16 binary digits.
A-instructions
Instructions whose most significant bit is “0” are called A-instructions or address instructions. The A-instruction is bit-field encoded as follows:
0b14b13b12b11b10b9b8b7b6b5b4b3b2b1b0
0 – the most significant bit of a A-instruction is “0”
b14 - b0 - these bits provide the binary representation of a non-negative integer in the decimal range 0 through 32767
When this instruction is executed, the remaining 15 bits are left-zero extended and loaded into the CPU's A-register. As a side-effect, the RAM register having the address represented by that value is enabled for subsequent read/write action in the next clock cycle.
C-instructions
The other instruction type, known as C-instructions (computation instructions) is the programming working horse. It has “1” as the most significant bit. The remaining 15 bits are bit-field encoded to define the operands, computation performed, and storage location for the specified computation result. This instruction may also specify a program branch based on the most recent computation result. he format is
C-instruction: dest=comp;jump, either the dest or jump may be empty giving two options dest=comp or comp;jump
The C-instruction is bit-field encoded as follows:
111a c1c2c3c4 c5c6d1d2 d3j1j2j3
1 – the most significant bit of a C-instruction is “1”
11 – these second two bits are ignored by the CPU and, by convention, are each always set to “1”
a – this bit specifies the source of the “y” operand of the ALU when it is used in a computation
c1-c6 – these six control bits specify the operands and computation to be performed by the ALU
d1-d3 – these three bits specify the destination(s) for storing the current ALU output
j1-j3 – these three bits specify an arithmetic branch condition, an unconditional branch (jump), or no branching
The Hack computer encoding scheme of the C-instruction is shown in the following tables.
In these tables,
A represents the value currently contained in the A-register
D represents the value currently contained in the D-register
M represents the value currently contained in the data memory register whose address is contained in the A-register; that is, M == RAM[A]
Assembly language
The Hack computer has a text-based assembly language to create programs for the hardware platform that implements the Hack computer ISA. Hack assembly language programs may be stored in text files having the file name extension “.asm”. Hack assembly language source files are case sensitive. Each line of text contains one of the following elements:
Blank line
Comment
Label declaration (with optional end-of-line comment)
A-instruction (with optional end-of-line comment)
C-instruction (with optional end-of-line comment)
Each of these line types has a specific syntax and may contain predefined or user defined symbols or numeric constants. Blank lines and comments are ignored by the assembler. Label declarations, A-instructions, and C-instructions, as defined below, may not include any internal white-space characters, although leading or trailing whitespace is permitted (and ignored).
Comments
Any text beginning with the two-character sequence “//” is a comment. Comments may appear on a source code line alone, or may also be placed at the end of any other program source line. All text following the comment identifier character sequence to end of line is completely ignored by the assembler; consequently, they produce no machine code.
Symbols and numeric constants
Hack assembly language allows the use of alphanumeric symbols for number of different specific purposes. A symbol may be any sequence of alphabetic (upper and lower case) or numeric digits. Symbols may also contain any of the following characters: under bar (“_”), period(“.”), dollar sign (“$”), and colon (“:”). Symbols may not begin with a digit character. Symbols are case sensitive. User defined symbols are used to create variable names and labels (see below).
The Hack assembly language assembler recognizes some predefined symbols for use in assembly language programs. The symbols R0, R1, …, R15 are bound respectively to the integers 0 through 15. These symbols are meant to represent general purpose registers and the symbols values therefore represent data memory addresses 0 through 15. Predefined symbols SCREEN and KBD are also specified to represent the data memory address of the start of memory-mapped virtual screen output (16384) and keyboard input (24756). There are a few other symbols (SP, LCL, ARG, THIS, and THAT) that are used in building the operating system software stack.
A string of decimal (0-9) digits may be used to represent a non-negative, decimal constant in the range 0 through 32,767. The use of the minus sign to indicate a negative number is not allowed. Binary or octal representation is not supported.
Variables
User defined symbols may be created in an assembly language program to represent variables; that is, a named RAM register. The symbol is bound at assembly to a RAM address chosen by the assembler. Therefore, variables must be treated as addresses when appearing in assembly language source code.
Variables are implicitly defined in assembly language source code when they are first referenced in an A-instruction. When the source code is processed by the assembler, the variable symbol is bound to a unique positive integer value in beginning at address 16. Addresses are sequentially bound to variable symbols in the order of their first appearance in the source code. By convention, user-defined symbols that identify program variables are written in all lower case.
Labels
Labels are symbols delimited by left "(" and right ")" parenthesis. They are defined on a separate source program line and are bound by the assembler to the address of the instruction memory location of the next instruction in the source code. Labels may be defined only once, but they may be used multiple times anywhere within the program, even before the line on which they are defined. By convention, labels are expressed in all-caps. They are used to identify the target address of branch C-instructions.
A-instructions
The A-instruction has the syntax “@xxxx”, where xxxx is either a numeric decimal constant in the range 0 through 32767, a label, or a variable (predefined or user defined). When executed, this instruction sets the value of the A register and the M pseudo-register to a 15-bit binary value represented by “xxxx”. The 15-bit value is left-zero extended to 16-bits in the A register.
The A-instruction may be used for one of three purposes. It is the only means to introduce a (non-negative) numeric value into the computer under program control; that is, it may be used to create program constants. Secondly, it is used to specify a RAM memory location using the M pseudo-register mechanism for subsequent reference by a C-instruction. Finally, a C-instruction which specifies a branch uses the current value of the A register as the branch target address. The A-instruction is used to set that target address prior to the branch instruction, usually by reference to a label.
C-Instructions
C-instructions direct the ALU computation engine and program flow control capabilities of the Hack computer. The instruction syntax is defined by three fields, referred to as “comp”, “dest”, and “jump”. The comp field is required in every C-instruction. The C-instruction syntax is “dest=comp;jump”. The “=” and “;” characters are used to delimit the fields of the instruction. If the dest field is not used, the “=” character is omitted. If the jump field is not used, the “;” character is omitted. The C-instruction allows no internal spaces.
The comp field must be one of the 28 documented mnemonic codes defined in the table above. These codes are considered distinct units; they must be expressed in all-caps with no internal spaces. It is noted that the 6 ALU control bits could potentially specify 64 computational functions; however, only the 18 presented in the table are officially documented for recognition by the assembler.
The dest field may be used to specify one or more locations to store the result of the specified computation. If this field is omitted, along with the “=” delimiter, the computed value is not stored. The allowed storage location combinations are specified by the mnemonic codes defined in the table above.
The jump field may be used to specify the address in ROM of the next instruction to be executed. If the field is omitted, along with the “;” delimiter, execution continues with the instruction immediately following the current instruction. The branch address target, in ROM, is provided by the current value of the A register if the specified branch condition is satisfied. If the branch condition fails, execution continues with the next instruction in ROM. Mnemonic codes are provided for six different comparisons based on the value of the current computation. Additionally, an unconditional branch is provided as a seventh option. Because the comp field must always be supplied, even though the value is not required for the unconditional branch, the syntax of this instruction is given as “0;JMP”. The branch conditions supported are specified in the table above.
Assembler
Freely available software supporting the Hack computer includes a command line assembler application. The assembler reads Hack assembly language source tiles (*.asm) and produces Hack machine language output files (*.hack). The machine language file is also a text file. Each line of this file is a 16-character string of binary digits that represents the encoding of each corresponding executable line of the source text file according to the specification described in the section "Instruction set architecture (ISA) and machine language". The file created may be loaded into the Hack computer emulator by a facility provided by the emulator user interface.
Example Assembly Language Program
Following is an annotated example program written in Hack assembly language. This program sums the first 100 consecutive integers and places the result of the calculation in a user-defined variable called “sum”. It implements a “while” loop construct to iterate though the integer values 1 through 100 and adds each integer to a “sum” variable. The user-defined variable “cnt” maintains the current integer value through the loop. This program illustrates all of the features of the “documented” assembly language capabilities of Hack Computer except memory-mapped I/O. It is Hack Assembly translation of the C fragment:
// Adds 1+...+100
int cnt = 1;
int sum = 0;
while (cnt <= 100) {
sum += cnt;
cnt++;
}
The contents of the Hack assembly language source file are shown in the second column in bold font. Line numbers are provided for reference in the following discussion but do not appear in the source code. The Hack machine code produced by the assembler is shown in the last column with the assigned ROM address in the preceding column. Note that full-line comments, blank lines, and label definition statements generate no machine language code. Also, the comments provided at the end of each line containing an assembly language instruction are ignored by the assembler.
The assembler output, shown in the last column, is a text string of 16 binary characters, not 16-bit binary integer representation.
Note that the instruction sequence follows the pattern of A-instruction, C-instruction, A-instruction, C-instruction, ... . This is typical for Hack assembly language programs. The A-instruction specifies a constant or memory address that is used in the subsequent C-instruction.
All three variations of the A-instruction are illustrated. In line 11 (@100), the constant value 100 is loaded into the A register. This value is used in line 12 (D=D-A) to compute the value used to test the loop branch condition.
Since line 4 (@cnt) contains the first appearance of the user-defined variable "cnt", this statement binds the symbol to the next unused RAM address. In this instance, the address is 16, and that value is loaded into the A register. Also, the M pseudo-register also now references this address, and RAM[16] is made the active RAM memory location.
The third use of the A-instruction is seen in line 21 (@LOOP). Here the instruction loads the bound label value, representing an address in ROM memory, into the A register and M pseudo-register. The subsequent unconditional branch instruction in line 22 (0;JMP) loads the M register value into the CPU's program counter register to effect control transfer to the beginning of the loop.
The Hack computer provides no machine language instruction to halt program execution. The final two lines of the program (@END and 0;JMP) create an infinite loop condition which Hack assembly programs conventionally use to terminate programs designed to run in the CPU emulator.
See also
Hennessy, John L., & Patterson, David A. (2019). Computer Architecture: A Quantitative Approach, 6th Edition. Cambridge, Massachusetts: Morgan Kaufmann Publishers
Justice, Matthew. (2021). How Computers Really Work. San Francisco, California: No Starch Press.
Malvino, Albert P., & Brown, Jerald A. (1993). Digital Computer Electronics, 3rd Edition. New York, New York: Glencoe McGraw-Hill
Null, Linda, & Lobur, Julia. (2019). The Essentials of Computer Organization and Architecture. 5th Edition. Burlington, Massachusetts: Jones and Bartlett Learning.
Patt, Yale N., & Patel, Sanjay J. (2020). Introduction to Computing Systems: From Bits and Gates to C and Beyond, 3rd Edition. New York, New York: McGraw Hill Education.
Petzold, Charles. (2009). Code: The Hidden Language of Computer Hardware and Software. Redmond, Washington: Microsoft Press.
Scott, John Clark. (2009). But How Do It Know? The Basic Principles of Computers for Everyone. Oldsmar, Florida: John C. Scott.
Whipple, Richard. (2019). Build Your Own Computer from Scratch. Seattle, Washington: Amazon Kindle.
References
Computers | Hack computer | [
"Technology"
] | 5,499 | [
"Computers"
] |
68,471,315 | https://en.wikipedia.org/wiki/Rubellite | Rubellite is the red or pink variety of tourmaline and is a member of elbaite. Rubellite is also the rarest gem in its family. It is occasionally mistaken for ruby. These gems typically contain inclusions.
Notable countries where rubellite can be mined include Afghanistan, Brazil, Madagascar, Myanmar, Nigeria, Russia, and the United States.
Name
Rubellite is named after the Latin word , meaning "reddish". The word rubellite was first used in the year 1794.
The gem is also called aphrite, apyrite, rubelite, or rubylite.
History
Rubellite crystals were known in Europe when specimens were imported from the East as early as Roman times, however these rubellite specimens were confused with other red gemstones, such as some garnets and spinels.
Value
Rubellite used to be the most expensive and prized gem in the tourmaline group but has since been eclipsed by the Paraiba tourmaline.
The most valuable specimens are colored red and lack brown. Those that are of ruby color are the most valuable.
References
Gemstones
Tourmalines | Rubellite | [
"Physics"
] | 235 | [
"Materials",
"Gemstones",
"Matter"
] |
74,345,420 | https://en.wikipedia.org/wiki/Burp%20Suite | Burp Suite is a proprietary software tool for security assessment and penetration testing of web applications. It was initially developed in 2003-2006 by Dafydd Stuttard to automate his own security testing needs, after realizing the capabilities of automatable web tools like Selenium. Stuttard created the company PortSwigger to flagship Burp Suite's development. A community, professional, and enterprise version of this product are available.
Notable capabilities in this suite include features to proxy web-crawls (Burp Proxy), log HTTP requests/responses (Burp Logger and HTTP History), capture/intercept in-motion HTTP requests (Burp Intercept), and aggregate reports which indicate weaknesses (Burp Scanner). This software uses a built-in database containing known-unsafe syntax patterns and keywords to search within captured HTTP requests/responses.
Burp Suite possesses several penetration-type functionalities. A few built-in PoC services include tests for HTTP downgrade, interaction with tool-hosted external sandbox servers (Burp Collaborator), and analysis for pseudorandomization strength (Burp Sequencer). This tool permits integration of user-defined functionalities through download of open-source plugins (such as Java Deserialization Scanner and Autorize).
Features
As a web security analyzer, Burp Suite offers several built-in features designed to assist testers in auditing their web applications.
Community Edition
The Community Edition version of Burp Suite includes the following features.
Burp Proxy and Interceptor: Like other web application security scanners, one of the primary functionalities behind Burp Suite is its capability to act as a proxy server for client-side HTTP requests. Penetration testers can intercept web servers' default HTTP requests variables (attributes, body parameters, cookies, headers) in real-time and edit these values on-the-fly.
Burp Site Map: BurpSuite operates similarly to the OWASP ZAP software, wherein target URLs' site maps can be captured either through automatic or manual web-crawling. When users crawl through a web application, HTTP requests become sent to a web proxy in Burp Suite's software. Once HTTP requests/responses are captured, these endpoints can be investigated manually or audited automatically through features in Burp Suite's Professional edition.
Burp Logger and HTTP History: Retains a list of HTTP requests/responses captured during web-crawling (and automated scanning for Professional edition).
Burp Repeater: Repeats captured HTTP requests, allowing custom changes to request variables.
Burp Decoder: Automates text decoding.
Burp Sequencer: Analyzes an application-generated token variable across repeated HTTP requests to determine pseudorandomness predictability strength.
Burp Comparer: Allows users to compare content found between two different HTTP requests or HTTP responses.
Burp Extender: See the Burp Extender section below; certain Burp Suite plugins are limited to only interact with Professional edition.
Professional Edition
Burp Suite's Professional edition includes all Community features plus those listed below.
Burp Scanner: Automates report auditing and/or web crawling for HTTP captured requests/responses. Uses internal rules to audit contents from intercepted HTTP responses in order to search for vulnerable response values. Capacitates users to customize scanners' speeds and findings coverage.
Burp Dashboard: Displays findings results and categorizes issues based on severity. Detailed descriptions and remediation steps may be provided based on what type of finding.
Burp Intruder: Similarly to Burp Repeater at a broader extent, grants users the means to send multiple parallel HTTP requests with changes to specified request variables.
Burp Collaborator: Simulates C2 Server hosting to attempt external service interaction and Out-of-Band attacks.
Burp Organizer: Allows users to curate selected HTTP requests/responses into a saved collection.
Burp Infiltrator: An IAST agent scripted to automate interactive/runtime scanning and communicate results through the Burp Collaborator feature.
Burp Clickbandit: A tool to concept proof to test clickjacking attacks against web applications' front-end HTML and JavaScript files.
File Saving: Professional edition allows users to save their projects as ".burp" files.
Burp Extender
BApps
Burp Suite offers an extension store where users can upload and download plugins for functionalities not supported natively. Different plugins alter in functionality, ranging from adjustments for UI readability, additions to scanner rules, and implementations of new analysis-based features.
Burp Suite's extension API is open-source. Support for Java plugins is natively supported, while extensions which use Python and Ruby require users to download JAR files for Jython and JRuby respectively.
Many Burp plugins have also been created by Portswigger employees as a means of developing proof-of-concepts for research conducted by the company. Examples of these include extensions created by James Kettle, Portswigger's Director of Research, including Backslash Powered Scanner, Param Miner, and HTTP Request Smuggler.
BChecks
BChecks were added to Burp Suite in June 2023 as a means of permitting users to create and customize their own scanner rules. A curated collection of BChecks are maintained by Portswigger through an open-source GitHub project.
Bambdas
Users can write Java scripts to create custom HTTP request/response index filtering in Burp Suite's proxy HTTP History, WebSocket History, and Logger lists.
See also
Application security
Dynamic Application Security Testing (DAST)
Vulnerability Assessment (Computing)
Information technology security assessment
OWASP ZAP
Web Crawler
Web Proxy Servers
References
External links
Computer security software
Free security software
Injection exploits
Java platform software | Burp Suite | [
"Technology",
"Engineering"
] | 1,180 | [
"Cybersecurity engineering",
"Computer security software",
"Computer security exploits",
"Injection exploits"
] |
74,346,583 | https://en.wikipedia.org/wiki/Indirect%20branch%20tracking | Indirect branch tracking (IBT), also known as branch target identification (BTI), is a control flow integrity mechanism implemented on some Intel x86-64 and ARM-64 processors. IBT is designed to protect against computer security exploits that use indirect branch instructions to jump into code in unintended ways, such as return-oriented programming.
It creates a special "branch target" instructions that have no function other than to mark a location as a valid indirect branch target, with the processor capable of being put into a mode where it will raise an exception if an indirect branch is made to a location without a branch target instruction.
Implementations
On Intel processors, the technique is known as Indirect Branch Tracking (IBT), with the "end branch" instructions and acting as the branch target instructions for 32 and 64 bit mode respectively. IBT is part of the Intel Control-Flow Enforcement Technology first released in the Tiger Lake generation of processors.
The similar technology on ARM-64 processors is called Branch Target Identification (BTI), with the instruction, also called , having three variants that make it check only for jumps, or function calls, or for both.
References
Computer security
Control flow integrity | Indirect branch tracking | [
"Technology",
"Engineering"
] | 242 | [
"Computer security stubs",
"Computing stubs",
"Control flow integrity",
"Cybersecurity engineering"
] |
74,349,529 | https://en.wikipedia.org/wiki/NGC%207236 | NGC 7236 is an interacting lenticular galaxy located in the constellation Pegasus. It is located at a distance of about 300 million light years from Earth, which, given its apparent dimensions, means that NGC 7236 is about 150,000 light years across. NGC 7236 forms a pair with NGC 7237 and is a radio galaxy. It was discovered by Albert Marth on August 25, 1864.
NGC 7236 forms a pair with elliptical galaxy NGC 7237, which lies 35 arcseconds to the southeast. The two galaxies are undergoing a merger and are surrounded by hot gas (corona) with temperature of around 1 keV. The total mass of that gas is estimated to be . A smaller elliptical galaxy, NGC 7237C, lies 38 arcseconds southeast of NGC 7237. A faint tail emanates from NGC 7236. It is included in the Atlas of Peculiar Galaxies, in the category diffuse counter-tails. A tail is also visible in X-rays. A dust lane runs across the galaxy.
The galaxy pair is a source of radiowaves. The radio emission has a double lobe structure, with filaments, but no jets, while a weak core is identified as the nucleus of NGC 7237. The filaments could be created by the interaction of hot gas with the preexisting radio emitting plasma. Some bright radio sources are visible within the lobes but they could be background active galaxies.
One supernova has been observed in NGC 7236: SN2019krv (typeIa, mag. 18.4).
See also
List of NGC objects (7001–7840)
Gallery
References
External links
NGC 7236 on SIMBAD
Lenticular galaxies
Interacting galaxies
Radio galaxies
Pegasus (constellation)
7236
11958
169
442
068384
Discoveries by Albert Marth
Astronomical objects discovered in 1864 | NGC 7236 | [
"Astronomy"
] | 377 | [
"Pegasus (constellation)",
"Constellations"
] |
74,350,224 | https://en.wikipedia.org/wiki/John%20S.%20Montmollin | John Samuel de Montmollin II (1808 – June 9, 1859) of Savannah, Georgia, was an American slave trader, banker and plantation owner. According to descendants, Montmollin was heavily involved in the organization of the illegal slave transport Wanderer. Montmollin died in a steamboat boiler explosion on the Savannah River in 1859.
Biography
Montmollin's maternal grandfather was Jonathan Edwards the younger, thus he was a first cousin, once removed, to Aaron Burr; as vice president, Burr stayed at the Montmollin home in 1802 while visiting Savannah. Montmollin married at Savannah, in 1842, Miss Harriet M. Rossignol. In 1848, he was a city marshal of Savannah, where he owned a plantation.
Montmollin was president of the Mechanics' Savings Bank of Savannah, which had been organized in 1854, and had capital amounting to in 1857. Beginning in 1856, he funded the construction of a still-extant three-story brick building now known as the John Montmollin Warehouse. The third floor was a slave pen (after the city was occupied by Union troops during the American Civil War the building was turned into a school for the city's African-American children, most of whom had never before had the opportunity to learn how to read or write). In December 1858 Montmollin sought to purchase "one or two gangs of rice field Negros." According to his daughter-in-law, who was interviewed in 1931, Montmollin sought to reopen the transatlantic slave trade and was responsible for organizing the illegal human trafficking transport Wanderer in 1858.
John S. Montmollin was one of approximately eleven people killed when a boiler exploded on the Savannah River steamboat John G. Lawton on June 9, 1859. His body was found "imbedded in the marsh, head downwards, to the hips, some seventy to eighty yards from where the explosion occurred, showing it must have been driven very high into the air. A handkerchief, which he had in his hand at the time of the accident, was still tight in his grasp."
Montmollin was killed "within a short distance of the spot where his [Wanderer] captives had been incarcerated" on an island in the Savannah River.
Following Montmollin's death, his widow found that "her husband died owing debts of more than $30,000" and so in 1863 petitioned a court for permission to sell the estate slaves she had inherited. Permission was granted and she sold 81 slaves in Savannah in April 1863 for .
See also
List of Georgia slave traders
Timeline of Savannah, Georgia
Georgia in the American Civil War
Nelson C. Trowbridge, another slave trader involved with the Wanderer
References
1808 births
1859 deaths
19th-century American criminals
19th-century pirates
Accidental deaths in Georgia (U.S. state)
American bank presidents
American slave owners
American mass murderers
American pirates
American proslavery activists
John
People from Savannah, Georgia
19th-century American slave traders
Deaths from explosion
History of slavery in Georgia (U.S. state)
19th-century American planters
Wanderer (slave ship) | John S. Montmollin | [
"Chemistry"
] | 631 | [
"Deaths from explosion",
"Explosions"
] |
74,350,900 | https://en.wikipedia.org/wiki/NGC%207237 | NGC 7237 is an interacting lenticular galaxy located in the constellation Pegasus. It is located at a distance of about 350 million light years from Earth, which, given its apparent dimensions, means that NGC 7237 is about 240,000 light years across. NGC 7237 forms a pair with NGC 7236 and is a radio galaxy. It was discovered by Albert Marth on August 25, 1864.
NGC 7237 forms a pair with lenticular galaxy NGC 7236, which lies 35 arcseconds to the northwest. The two galaxies are undergoing a merger and are surrounded by hot gas (corona) with temperature of around 1 keV. The total mass of that gas is estimated to be . A smaller elliptical galaxy, NGC 7237C, lies 38 arcseconds southeast of NGC 7237. It is included in the Atlas of Peculiar Galaxies, in the category diffuse counter-tails. A tail is also visible in X-rays. The isophotes in the central region of NGC 7237 are irregular.
The galaxy pair is a source of radiowaves. The radio emission has a double lobe structure, with filaments, but no jets, while a weak core is identified as the nucleus of NGC 7237. The filaments could be created by the interaction of hot gas with the preexisting radio emitting plasma. Some bright radio sources are visible within the lobes but they could be background active galaxies. The core has been found to be variable source of X-rays.
Gallery
References
External links
NGC 7237 on SIMBAD
Lenticular galaxies
Interacting galaxies
Radio galaxies
Pegasus (constellation)
7237
11958
169
442
68384
Discoveries by Albert Marth
Astronomical objects discovered in 1864 | NGC 7237 | [
"Astronomy"
] | 347 | [
"Pegasus (constellation)",
"Constellations"
] |
74,357,366 | https://en.wikipedia.org/wiki/NGC%203801 | NGC 3801 is a lenticular galaxy located in the constellation Leo. It is about 150 million light years from Earth, and estimated to be about 170,000 light years in diameter. William Herschel discovered it on 17 April 1784.
Characteristics
The morphology of NGC 3801 is disturbed, indicating that the galaxy underwent a merger with another gas rich galaxy. A dust lane runs across the galaxy in its eastern half while a smaller one is visible perpendicular to that along the minor axis. A tidal tail about 1.2 arcminutes long extends to the east-southeast of the galaxy. The halo of the galaxy appears boxy.
NGC 3801 has been found to emit radio waves. It is a compact Fanaroff–Riley type I radio galaxy, with the total extent of the jets being 40 arcseconds. Both jets appear to curve while the core is not visible in observations by the Very Large Array. The radio jets have been found to heat the interstellar medium to a temperature of 1 and 0.7 keV. A linear feature is visible in soft X-rays extending along the jet axis, possibly a tidal tail.
CO imaging indicates the presence of an edge-on disk with a radius 2 kpc perpendicular to the radio jets axis, with a molecular gas mass of , about 1% of the dynamical mass of the galaxy. There is also a clump of molecular gas not associated with the disk that appears to fall towards the galaxy. The radio jet axis is aligned with the main HI disk of the galaxy.
When observed in ultraviolet, the galaxy is shaped like an s-shape, with the western half being brighter than the eastern half, indicating the presence of a very warped disk. Both halves extend for 60–70 arcseconds. Small UV clumps appear along the galaxy, that indicate the presence of stars. The age of the stellar population in the clumps is estimated to be between 100 and 500 Myr, with most star forming activity taking place before 400 Myr. The location of the most vigorous starburst appears to be the central region of the galaxy.
In the centre of NGC 3801 lies a supermassive black hole whose mass is estimated to be 108.28 ± 0.31 (93 – 390 millions) based on gas dynamics or based on stellar velocity dispersion. The nucleus of the galaxy has been categorised as in between a Seyfert galaxy and a LINER.
Nearby galaxies
NGC 3801 is the foremost galaxy of the galaxy group known as NGC 3801 group or LGG 246. Other members of the group include the galaxies NGC 3768, NGC 3790, NGC 3799, NGC 3800, NGC 3802, NGC 3806, NGC 3827, and NGC 3853. NGC 3802 lies 2.3 arcminutes from NGC 3801 while NGC 3790 lies 7 arcminutes away. HI imaging shows a hydrogen bridge that appears to link NGC 3801 and NGC 3802, indicating the two galaxies are interacting.
Gallery
See also
3C 285 - a similar radio galaxy
References
External links
NGC 3801 on SIMBAD
Lenticular galaxies
Interacting galaxies
Radio galaxies
Leo (constellation)
3801
06635
+17.52
36200
Astronomical objects discovered in 1784
Discoveries by William Herschel | NGC 3801 | [
"Astronomy"
] | 670 | [
"Leo (constellation)",
"Constellations"
] |
74,358,254 | https://en.wikipedia.org/wiki/Projection%20filters | Projection filters are a set of algorithms based on stochastic analysis and information geometry, or the differential geometric approach to statistics, used to find approximate solutions for filtering problems for nonlinear state-space systems.
The filtering problem consists of estimating the unobserved signal of a random dynamical system from partial noisy observations of the signal. The objective is computing the probability distribution of the signal conditional on the history of the noise-perturbed observations. This distribution allows for calculations of all statistics of the signal given the history of observations. If this distribution has a density, the density satisfies specific stochastic partial differential equations (SPDEs) called Kushner-Stratonovich equation, or Zakai equation.
It is known that the nonlinear filter density evolves in an infinite dimensional function space.
One can choose a finite dimensional family of probability densities, for example Gaussian densities, Gaussian mixtures, or exponential families, on which the infinite-dimensional filter density can be approximated. The basic idea of the projection filter is to use a geometric structure in the chosen spaces of densities to project the infinite dimensional SPDE of the optimal filter onto the chosen finite dimensional family, obtaining a finite dimensional stochastic differential equation (SDE) for the parameter of the density in the finite dimensional family that approximates the full filter evolution. To do this, the chosen finite dimensional family is equipped with a manifold structure as in information geometry.
The projection filter was tested against the optimal filter for the cubic sensor problem. The projection filter could track effectively bimodal densities of the optimal filter that would have been difficult to approximate with standard algorithms like the extended Kalman filter.
Projection filters are ideal for in-line estimation, as they are quick to implement and run efficiently in time, providing a finite dimensional SDE for the parameter that can be implemented efficiently.
Projection filters are also flexible, as they allow fine tuning the precision of the approximation by choosing richer approximating families, and some exponential families make the correction step in the projection filtering algorithm exact. Some formulations coincide with heuristic based assumed density filters or with Galerkin methods. Projection filters can also approximate the full infinite-dimensional filter in an optimal way, beyond the optimal approximation of the SPDE coefficients alone, according to precise criteria such as mean square minimization. Projection filters have been studied by the Swedish Defense Research Agency and have also been successfully applied to a variety of fields including navigation, ocean dynamics, quantum optics and quantum systems, estimation of fiber diameters, estimation of chaotic time series, change point detection and other areas.
History and development
The term "projection filter" was first coined in 1987 by Bernard Hanzon, and the related theory and numerical examples were fully developed, expanded and made rigorous during the Ph.D. work of Damiano Brigo, in collaboration with Bernard Hanzon and Francois LeGland.
These works dealt with the projection filters in Hellinger distance and Fisher information metric, that were used to project the optimal filter infinite-dimensional SPDE on a chosen exponential family. The exponential family can be chosen so as to make the prediction step of the filtering algorithm exact.
A different type of projection filters, based on an alternative projection metric, the direct metric, was introduced in Armstrong and Brigo (2016). With this metric, the projection filters on families of mixture distributions coincide with filters based on Galerkin methods. Later on, Armstrong, Brigo and Rossi Ferrucci (2021) derive optimal projection filters that satisfy specific optimality criteria in approximating the infinite dimensional optimal filter. Indeed, the Stratonovich-based projection filters optimized the approximations of the SPDE separate coefficients on the chosen manifold but not the SPDE solution as a whole. This has been dealt with by introducing the optimal projection filters. The innovation here is to work directly with Ito calculus, instead of resorting to the Stratonovich calculus version of the filter equation. This is based on research on the geometry of Ito Stochastic differential equations on manifolds based on the jet bundle, the so-called 2-jet interpretation of Ito stochastic differential equations on manifolds.
Projection filters derivation
Here the derivation of the different projection filters is sketched.
Stratonovich-based projection filters
This is a derivation of both the initial filter in Hellinger/Fisher metric sketched by Hanzon and fully developed by Brigo, Hanzon and LeGland, and the later projection filter in direct L2 metric by Armstrong and Brigo (2016).
It is assumed that the unobserved random signal is modelled by the Ito stochastic differential equation:
where f and are valued and is a Brownian motion. Validity of all regularity conditions necessary for the results to hold will be assumed, with details given in the references. The associated noisy observation process is modelled by
where is valued and is a Brownian motion independent of . As hinted above, the full filter is the conditional
distribution of given a prior for
and the history of up to time . If this distribution has a density described informally as
where is the sigma-field generated by the history of noisy observations up to time , under suitable technical conditions the density satisfies the Kushner—Stratonovich SPDE:
where is the expectation
and the forward diffusion operator is
where and denotes transposition.
To derive the first version of the projection filters, one needs to put the SPDE in Stratonovich form. One obtains
Through the chain rule, it's immediate to derive the SPDE for .
To shorten notation one may rewrite this last SPDE as
where the operators and are defined as
The square root version is
These are Stratonovich SPDEs whose solutions evolve in infinite dimensional function spaces. For example may evolve in (direct metric )
or may evolve in (Hellinger metric )
where is the norm of Hilbert space .
In any case, (or ) will not evolve inside any finite dimensional family of densitities,
The projection filter idea is approximating (or ) via a finite dimensional density (or ).
The fact that the filter SPDE is in Stratonovich form allows for the following. As Stratonovich SPDEs satisfy the chain rule, and behave as vector fields. Thus, the equation is characterized by a vector field and a vector field . For this version of the projection filter one is satisfied with dealing with the two vector fields separately.
One may project and on the tangent space of the densities in (direct metric) or of their square roots (Hellinger metric). The direct metric case yields
where is the tangent space projection at the point for the manifold , and where, when applied to a vector such as , it is assumed to act component-wise by projecting each of 's components. As a basis of this tangent space is
by denoting the inner product of with , one defines the metric
and the projection is thus
where is the inverse of .
The projected equation thus reads
which can be written as
where it has been crucial that Stratonovich calculus obeys the chain rule. From the above equation, the final projection filter SDE is
with initial condition a chosen .
By substituting the definition of the operators F and G we obtain the fully explicit projection filter equation in direct metric:
If one uses the Hellinger distance instead, square roots of densities are needed. The
tangent space basis is then
and one defines the metric
The metric is the Fisher information metric. One follows steps completely analogous to the direct metric case and the filter equation in Hellinger/Fisher metric is
again with initial condition a chosen .
Substituting F and G one obtains
The projection filter in direct metric, when implemented on a manifold of mixture families, leads to equivalence with a Galerkin method.
The projection filter in Hellinger/Fisher metric when implemented on a manifold of square roots of an exponential family of densities is equivalent to the assumed density filters.
One should note that it is also possible to project the simpler Zakai equation for an unnormalized version of the density p. This would result in the same Hellinger projection filter but in a different direct metric projection filter.
Finally, if in the exponential family case one includes among the sufficient statistics of the exponential family the observation function in , namely 's components and , then one can see that the correction step in the filtering algorithm becomes exact. In other terms, the projection of the vector field is exact, resulting in itself. Writing the filtering algorithm in a setting with continuous state and discrete time observations , one can see that the correction step at each new observation is exact, as the related Bayes formula entails no approximation.
Optimal projection filters based on Ito vector and Ito jet projections
Now rather than considering the exact filter SPDE in Stratonovich calculus form, one keeps it in Ito calculus form
In the Stratonovich projection filters above, the vector fields and were projected separately. By definition, the projection is the optimal approximation for and separately, although this does not imply it provides the best approximation for the filter SPDE solution as a whole. Indeed, the Stratonovich projection, acting on the two terms and separately, does not guarantee optimality of the solution as an approximation of the exact for say small . One may look for a norm to be applied to the solution, for which
The Ito-vector projection is obtained as follows.
Let us choose a norm for the space of densities, , which might be associated with the direct metric or the Hellinger metric.
One chooses the diffusion term in the approximating Ito equation for by minimizing (but not zeroing) the term of the Taylor expansion for the mean square error
,
finding the drift term in the approximating Ito equation that minimizes the term of the same difference. Here the order term is minimized, not zeroed, and one never attains convergence, only convergence.
A further benefit of the Ito vector projection is that it minimizes the order 1 Taylor expansion in of
To achieve convergence, rather than convergence, the Ito-jet projection is introduced. It is based on the notion of metric projection.
The metric projection of a density (or ) onto the manifold (or ) is the closest point on (or ) to (or ). Denote it by . The metric projection is, by definition, according to the chosen metric, the best one can ever do for approximating in . Thus the idea is finding a projection filter that comes as close as possible to the metric projection. In other terms, one considers the criterion
The detailed calculations are lengthy and laborious, but the resulting approximation achieves convergence.
Indeed, the Ito jet projection attains the following optimality criterion. It zeroes the order term and it minimizes the order term of the Taylor expansion of the mean square distance in between and .
Both the Ito vector and the Ito jet projection result in final SDEs, driven by the observations , for the parameter that best approximates the exact filter evolution for small times.
Applications
Jones and Soatto (2011) mention projection filters as possible algorithms for on-line estimation in visual-inertial navigation, mapping and localization, while again on navigation Azimi-Sadjadi and Krishnaprasad (2005) use projection filters algorithms.
The projection filter has been also considered for applications in ocean dynamics by Lermusiaux 2006. Kutschireiter, Rast, and Drugowitsch (2022) refer to the projection filter in the context of continuous time circular filtering. For quantum systems applications, see for example van Handel and Mabuchi (2005), who applied the quantum projection filter to quantum optics, studying a quantum model of optical phase bistability of a strongly coupled two-level atom in an optical cavity. Further applications to quantum systems are considered in Gao, Zhang and Petersen (2019). Ma, Zhao, Chen and Chang (2015) refer to projection filters in the context of hazard position estimation, while Vellekoop and Clark (2006) generalize the projection filter theory to deal with changepoint detection. Harel, Meir and Opper (2015) apply the projection filters in assumed density form to the filtering of optimal point processes with applications to neural encoding. Broecker and Parlitz (2000) study projection filter methods for noise reduction in chaotic time series. Zhang, Wang, Wu and Xu (2014)
apply the Gaussian projection filter as part of their estimation technique to deal with measurements of fiber diameters in melt-blown nonwovens.
See also
Filtering problem
Generalized filtering
Nonlinear filter
Extended Kalman filter
Recursive Bayesian estimation
References
Computational statistics
Nonlinear filters
Signal estimation
Control theory
Stochastic differential equations | Projection filters | [
"Mathematics"
] | 2,568 | [
"Applied mathematics",
"Control theory",
"Computational mathematics",
"Computational statistics",
"Dynamical systems"
] |
74,362,240 | https://en.wikipedia.org/wiki/International%20Association%20for%20the%20Study%20of%20Dreams | The International Association for the Study of Dreams (IASD) is a multi-disciplinary professional nonprofit organization for scientific dream research (oneirology), founded in 1983 and headquartered in the U.S.
The organization was originally named the Association for the Study of Dreams (ASD).
Scope
Attracting "a 'rainbow coalition' of scientists, scholars, therapists, cultural practitioners, artists, and the general public", the organization publishes scientific research across all dream-related subjects, including dreams in analytical psychology, oneirology, dreamwork, oneiromancy, and lucid dreaming via its:
International Association for the Study of Dreams Conference―annual conference alternating locations across the globe, held since 1984
Dreaming―a journal published by the American Psychological Association (APA) on behalf of IASD since 1991
International Journal of Dream Research (IJoDR) (ISSN: 1866–7953)―peer-reviewed, indexed in APA's PsycINFO and Elsevier's Scopus databases since 2008, and published on Heidelberg University Library servers
Funding and endorsement: The IASD has provided research grants, and has endorsed projects such as an art exhibition in Vienna and Paris from 1999 to 2001 and an associated book, Dreams 1900-2000.
Writing in 1989, psychology professor, Harry T. Hunt states that "on an organizational level, the Sleep Research Society (srs) and its small cluster of researchers focusing on physiological, neurocognitive, and content analysis approaches to dreams have been supplemented by a more eclectic organization, the Association for the Study of Dreams (asp) [sic]. Within ASD, a diverse group of Freudian, Jungian, existential, and other psychologists interested primarily in dream interpretation and 'dreamwork' has banded together with others attempting to relate dreams to altered states of consciousness and transpersonal psychology, and a small number of srs experimenters."
Writing more recently, in 2017, historian and academic, Jonson Miller states that "[t]he IASD is a scholarly association for the study of dreams, including dream interpretation, dreams in culture, creativity and dreams, the physiology of dreaming, and lucid dreaming. They publish two magazines and a newsletter, hold conferences (both traditional and online), and provide classes on dream work. Their website has many useful resources, including bibliographies, videos, podcasts, recordings from past conferences, and even images from dream art exhibitions."
Governance
The nonprofit has historically been led by the following researchers:
Gayle Delaney, PhD (1983–85) – IASD co-founder and Oprah dream expert
Stephen LaBerge, PhD – IASD co-founder, psychophysiologist and lucid dreaming specialist
Robert Van de Castle (1985–1986)
Ernest Hartmann, professor, psychoanalyst and sleep researcher (1987–1988)
Jayne Gackenbach, PhD (1988–1989)
Stanley Krippner, professor, psychologist and parapsychologist (1993–1994)
Deirdre Barrett, PhD (1995–96, 2023–24)
Kelly Bulkeley, PhD (1997–98)
Patricia Garfield, PhD (1998–99) – IASD co-founder
Mark Blagrove, professor of psychology and dream researcher (2001–2002)
Michelle Carr, PhD, dream researcher focused on lucid dreaming and other altered states of consciousness (2021–2023)
Notable members
G. William Domhoff, PhD – psychologist and author
Harry Fiss, PhD
Allan Hobson, MD
Robert Moss
Publications
Media appearances
See also
American Psychological Association
Dreamwork
Notes
References
External links
IASD Ethics in Dreamwork and Teaching Dreamwork
Carl Jung
Sigmund Freud
Oneirology
Dream
Analytical psychology
Psychoanalytic theory
Psychology organizations based in the United States
Symbols
American Psychological Association
International learned societies
Organizations established in 1983
1983 establishments in California
1983 establishments in the United States
Folsom, California | International Association for the Study of Dreams | [
"Mathematics",
"Biology"
] | 790 | [
"Oneirology",
"Behavior",
"Dream",
"Symbols",
"Sleep"
] |
74,365,644 | https://en.wikipedia.org/wiki/Virulent%3A%20The%20Vaccine%20War | Virulent: The Vaccine War is a 2022 documentary produced by Laura Davis and directed by Tjardus Greidanus which explores the history, dangers and impact of the anti-vaccination movement in the United States at the time of the COVID-19 pandemic.
Description
Virulent: The Vaccine War explores the history of vaccines and the perspectives of the opposition in light of the COVID-19 pandemic. The film posits that vaccine hesitancy is largely caused by two unconnected reasons, one is personal freedom and the other is opposition to anything that is seen as unnatural. The movie also explores conspiracy theories about vaccination created and spurred on by the anti-vaccination movement. Davis said that she was surprised to learn how complicated vaccine hesitancy is: "I really thought it was going to be easy to dismiss vaccine skeptics as not educated. It’s much subtler than I thought".
The film includes commentary by many medical experts, including the film's credited medical consultant, Paul Offit, and also identifies the big names and organizations in the anti-vaccine movement, including Del Bigtree, the CEO of the Informed Consent Action Network, and Robert F. Kennedy Jr., founder of Children's Health Defense who is interviewed in the film. Virulent highlights families impacted by preventable diseases in order to stress the importance of herd immunity from sufficient community vaccination. Davis said that "Most people won’t change their minds immediately after watching one film. But hopefully we can open up dialogue."
Production
Greidanus, the film's director, editor and cinematographer, has stated that being questioned at a film festival about the intent of his previous film on the subject of vaccinations, A Shot to Save the World, about the creation of the polio vaccine — regarding whether it was pro or anti vaccination — spurred him to dive further into that subject with Virulent. Production of the film began prior to the appearance of COVID-19, but due to pandemic, additional material was filmed and added.
Reception
Wendy M. Grossman writing about the film in The Skeptic said "overall, this is a well-done portrait of the American anti-vaxx movement as it’s developed over time. Well-informed skeptics are unlikely to find a lot that’s new, but the personal stories offer food for compassion. One of these is Offit’s own, which he gives in response to Kennedy’s accusation that he’s only in vaccines for the money. As a young child, Offit was kept on a pediatric polio ward while he recovered from surgery to correct a clubfoot. He never lost the memory of the vulnerable children he saw there or his resulting desire to protect them. "How exactly does Bobby Kennedy make the world a better place, please tell me that?" he asks, exasperated."
Stuart Vyse writing in Skeptical Inquirer said that the film "describes the rise of the anti-vaccination movement from long before COVID-19 to the present day," and that it "features interviews with pediatrician and author Dr. Paul Offit, surgical oncologist and managing editor of Science-Based Medicine Dr. David Gorski, and clinical neurologist and Skeptics' Guide to the Universe podcaster Dr. Steven Novella... Peter Salk, son of Salk vaccine discoverer Jonas Salk and president of The Jonas Salk Legacy Foundation, also appears in the film. The anti-vaccination position is presented in interviews with vaccine hesitant parents, as well as perhaps the most prominent and virulent anti-vax advocate, Robert F. Kennedy Jr." Vyse echoed the review of Jonathan Jarry of the McGill University Office for Science and Society who wrote that the film, "shows us what the modern anti-vaccine movement looks like and pushes back with stories of its own. … People need to see it."
The Center For Inquiry wrote that the film "examines the history of vaccine hesitancy, and the galvanizing effect Covid-19 has had on anti-vaccination activists." and it is "an invitation to think again, exposing the myths and laying bare the facts about vaccine science, its history, and what it will take to eradicate the world’s most deadly diseases." The review also said that the film "features scientists and others in the trenches including Dr. Paul Offit, one of the world’s preeminent virologists; public health expert Dr. Peter Salk, the son of polio vaccine inventor Dr. Jonas Salk; and New York Times columnist Kevin Roose, who writes about how disinformation spreads online."
David Gorski wrote in Science-Based Medicine that the film's message is important and related its themes to the coverage of the anti-vaccine movement by himself and other medical professionals, and said it is "a documentary that needs to be seen more widely."
See also
List of vaccine topics
References
External links
Official website
Vaccine controversies
Vaccination in the United States
Vaccine hesitancy
2022 documentary films
2022 films | Virulent: The Vaccine War | [
"Chemistry",
"Biology"
] | 1,069 | [
"Vaccination",
"Drug safety",
"Vaccine controversies"
] |
74,367,386 | https://en.wikipedia.org/wiki/Motorized%20potentiometer | A motorized potentiometer combines a potentiometer with an electric motor.
Uses
Motorized potentiometers can be found in audio/video equipment, specifically mixing consoles. In this application, they are called motorized faders. Mixing consoles with motorized faders typically are used to save and restore settings on the same console and sometimes to transfer settings to a different console. Save and restore also allows to control more channels then there are sliders by switching which tracks are controlled. While historically, the faders where literal motorized potentiometers, nowadays faders may directly digitize the fader position and apply the value digitally in the digital signal processing.
Motorized potentiometers are used in industrial controls.
Motorized potentiometers may be used for remote control applications.
Motorized potentiometers can be used to build electrical/electronic analog computers. The motorized potentiometer can act as a computing element, but also as a way to convert a physical into an electrical value.
Radio control servo motors use a potentiometer as feedback for the servo position.
Features
Some motorized potentiometers allow both manual and motorized operation.
Motorized potentiometers can be slide or rotary potentiometers. There also exist multiple turn motorized potentiometers.
The end of travel may be detected using limit switches, a peak in motor current as the mechanism stalls, or a separate resistive element used for position feedback.
History
Given that the history of the motorized potentiometer is linked to electronic analog computers, and electronic analog computers to military use, recording keeping and publication were limited, also meaning that parallel invention was highly likely. The M9 Gun Director had a potentiometer controlled by op amps. The Bomben-Abwurfrechner BT-9 has a motor driven potentiometer to convert a pressure into a potentiometer setting.
In 1968 a patent was filled describing a motor-potentiometer combination where the motor only engages when energized, allowing manual operation.
In 1970 a patent was filled describing a motor-potentiometer with overload clutch and interchangeable gear ratio.
Manufactures
Manufactures are for e.g. Alps Electric.
References
Resistive components
Analog computers | Motorized potentiometer | [
"Physics"
] | 445 | [
"Resistive components",
"Physical quantities",
"Electrical resistance and conductance"
] |
74,367,759 | https://en.wikipedia.org/wiki/Berkelium%28III%29%20oxychloride | Berkelium(III) oxychloride is an inorganic compound of berkelium, chlorine, and oxygen with the chemical formula BkOCl.
Physical properties
The compound forms very pale green crystals.
References
Oxychlorides
Berkelium compounds | Berkelium(III) oxychloride | [
"Chemistry"
] | 54 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
74,368,203 | https://en.wikipedia.org/wiki/Californium%28III%29%20oxybromide | Californium(III) oxybromide is a inorganic compound of californium, bromine, and oxygen with the formula CfOBr.
Physical properties
Californium bromide is obtained by heating in HBr.
The compound is isostructural with CfOCl. Both are prepared by the same method.
References
Californium compounds
Oxybromides | Californium(III) oxybromide | [
"Chemistry"
] | 83 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
74,368,247 | https://en.wikipedia.org/wiki/Californium%28III%29%20oxyiodide | Californium(III) oxyiodide is a inorganic compound of californium, iodine, and oxygen with the formula CfOI.
Synthesis
Californium iodide is obtained by heating in HI.
The compound is isostructural with CfOCl and CfOBr. All are prepared by the same method.
Physical properties
The compound forms dark crystals.
References
Californium compounds
Oxyiodides | Californium(III) oxyiodide | [
"Chemistry"
] | 92 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
71,354,664 | https://en.wikipedia.org/wiki/Lyra%20%28codec%29 | Lyra is a lossy audio codec developed by Google that is designed for compressing speech at very low bitrates. Unlike most other audio formats, it compresses data using a machine learning-based algorithm.
Features
The Lyra codec is designed to transmit speech in real-time when bandwidth is severely restricted, such as over slow or unreliable network connections. It runs at fixed bitrates of 3.2, 6, and 9 kbit/s and it is intended to provide better quality than codecs that use traditional waveform-based algorithms at similar bitrates. Instead, compression is achieved via a machine learning algorithm that encodes the input with feature extraction, and then reconstructs an approximation of the original using a generative model. This model was trained on thousands of hours of speech recorded in over 70 languages to function with various speakers. Because generative models are more computationally complex than traditional codecs, a simple model that processes different frequency ranges in parallel is used to obtain acceptable performance. Lyra imposes 20 ms of latency due to its frame size. Google's reference implementation is available for Android and Linux.
Quality
Lyra's initial version performed significantly better than traditional codecs at similar bitrates. Ian Buckley at MakeUseOf said, "It succeeds in creating almost eerie levels of audio reproduction with bitrates as low as 3 kbps." Google claims that it reproduces natural-sounding speech, and that Lyra at 3 kbit/s beats Opus at 8 kbit/s. Tsahi Levent-Levi writes that Satin, Microsoft's AI-based codec, outperforms it at higher bitrates.
History
In December 2017, Google researchers published a preprint paper on replacing the Codec 2 decoder with a WaveNet neural network. They found that a neural network is able to extrapolate features of the voice not described in the Codec 2 bitstream and give better audio quality, and that the use of conventional features makes the neural network calculation simpler compared to a purely waveform-based network. Lyra version 1 would reuse this overall framework of feature extraction, quantization, and neural synthesis.
Lyra was first announced in February 2021, and in April, Google released the source code of their reference implementation. The initial version had a fixed bitrate of 3 kbit/s and around 90 ms latency. The encoder calculates a log mel spectrogram and performs vector quantization to store the spectrogram in a data stream. The decoder is a WaveNet neural network that takes the spectrogram and reconstructs the input audio.
A second version (v2/1.2.0), released in September 2022, improved sound quality, latency, and performance, and permitted multiple bitrates. V2 uses a "SoundStream" structure where both the encoder and decoder are neural networks, a kind of autoencoder. A residual vector quantizer is used to turn the feature values into transferrable data.
Support
Implementations
Google's implementation is available on GitHub under the Apache License. Written in C++, it is optimized for 64-bit ARM but also runs on x86, on either Android or Linux.
Applications
Google Meet uses Lyra to transmit sound for video chats when bandwidth is limited.
References
External links
Lyra: A New Very Low-Bitrate Codec for Speech Compression Google blog post with a demonstration comparing codecs
See also
Satin (codec), an AI-based codec developed by Microsoft
Comparison of audio coding formats
Speech coding
Videotelephony
Speech codecs
Lossy compression algorithms
Software using the Apache license
Google software
Machine learning
2021 software | Lyra (codec) | [
"Engineering"
] | 764 | [
"Artificial intelligence engineering",
"Machine learning"
] |
71,355,816 | https://en.wikipedia.org/wiki/Leucocoprinus%20magnicystidiosus | Leucocoprinus magnicystidiosus is a species of mushroom-producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1982 by the mycologists Helen Vandervort Smith and Nancy S. Weber who classified it as Leucocoprinus magnicystidiosus. The specimens studied and documented were collected by Ervin Hillhouse in 1971.
Description
Leucocoprinus magnicystidiosus is a dapperling mushroom with extremely fragile white flesh.
Cap: 4–8cm wide when mature. Up to 1.3cm wide and 3.2cm high when young. Starts bulbous and expands to conical or campanulate (bell shaped) before flattening or becoming concave with the cap edges lifting upwards. The surface is bright lemon yellow with a brown centre when young. The cap edges have striate or plicate striations which extend nearly to the centre, the striations remain bright yellow whilst the grooves between them are white. The cap is very fragile at all stages of growth and easily sticks to the fingers and tears when examined. Stem: 7–15cm tall and 2.4mm thick. Roughly equal in width above the bulbous base. Yellow coloured, sometimes darker than the cap and sometimes with red or brown shades. Fragile and sometimes breaking naturally under the weight of the cap. The stem ring is yellow below and white above but may disappear quickly with only fragments remaining on the stem and cap margin. Gills: Yellow to white but paler than the top of the cap. Spores: Ovate to lemon shaped with a distinct pore. Dextrinoid. 9.0–13.5 x 7.5–9.0 μm. Basidia: 20–39 x 10–12μm. Four spored. Smell: Indistinct. Taste: Slightly bitter.
This mushroom is described as being 'extremely fragile'. The stem is so fragile that when the caps are fully open and mature even a slight breeze or human breath can cause them to break. Larger specimens may collapse under their own weight and hot sun causes these mushrooms to deteriorate and disappear very quickly. So on hot days they are only ever found in the early morning. Dried specimens present with a dark red tint across the centre of the cap and the striations.
Habitat and distribution
L. magnicystidiosus is scarcely recorded and little known. The specimens studied were gathered in Brazoria county, Texas in 1971 and Cades Cove, Tennessee in 1939. The later collection was described as growing in the Summer and Autumn and was found growing in scattered clusters amongst St. Augustine grass and pine. Specimens were also found growing from the soil in mixed woodland, in layers of fallen pine needles and in leaf covered grass. The mushrooms were described as being very abundant at times but fleeting and found only during and shortly after rain or in the early morning when heavy dew was present.
Similar species
Leucocoprinus fragilissimus usually has a smaller cap (2–5cm), brighter colours and has microscopic features which distinguish it from L. magnicystidiosus.
Leucocoprinus thoenii is described as looking similar and being separated by microscopic detail. However it is found in Africa.
References
magnicystidiosus
Fungi described in 1982
Fungus species
Fungi of North America | Leucocoprinus magnicystidiosus | [
"Biology"
] | 693 | [
"Fungi",
"Fungus species"
] |
71,356,147 | https://en.wikipedia.org/wiki/Leucocoprinus%20longistriatus | Leucocoprinus longistriatus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1898 by the American mycologist Charles Horton Peck and classified as Lepiota longistriata.
In 1982 it was reclassified as Leucocoprinus longistriatus by the mycologists Helen Vandervort Smith and Nancy S. Weber.
Description
Leucocoprinus longistriatus is a small dapperling mushroom with thin (2-6mm thick) white flesh.
Cap: 4.3–8 cm wide, convex or flat with the cap edges sometimes lifting upwards with age. The umbo can be distinct or not present when mature and the cap margins have finely striate or plicate grooves running almost to the centre when mature. The surface is pale yellow, white or grayish and is covered in fine scales that are easily removed whilst the centre is brown to dark red surrounding the umbo. Stem: 4–8.3 cm long and 3.6mm thick tapering up from a bulbous base of 6-12mm when mature. The surface is pale yellow or white and smooth but stains a dull ochre colour when young stems are handled, the interior flesh is hollow. The small, ascending stem ring has pale brown edges and is located below the middle of the stem and is often just above the base (inferior to basal) however it may disappear. Gills: Yellowish white, becoming darker with maturity or when dry. Crowded and free with slight tufts on the edges. Spores: Elliptical or ovate lacking a distinct pore. Non-dextrinoid. 6–8 x 4.5-5 μm.
Habitat and distribution
Peck described the species as growing in gardens in Alabama July with specimens also found in Cuba in gardens and amongst grass and in Jamaican woodland.
In a 1907 study the American mycologist Andrew Price Morgan documented the species growing in 'rich soil in gardens' in Alabama.
In 1937 Johannes Rick documented the species in Brazil but cited the name as Lepiota longestriata Peck. He stated that it grew in gardens and forests.
The 1982 study examined specimens found growing in tufts or scattered on wood chips and on soil under sweet gum and live oak trees. They were found in Jackson county, Mississippi.
References
Leucocoprinus
Fungi described in 1898
Fungus species | Leucocoprinus longistriatus | [
"Biology"
] | 487 | [
"Fungi",
"Fungus species"
] |
71,356,162 | https://en.wikipedia.org/wiki/Kevin%20Knuth | Kevin Hunter Knuth (born 1965) is a Professor of Physics at the University at Albany (SUNY). Knuth conducts research in information physics, foundations of quantum mechanics, and Bayesian analysis with applications towards various problems in physics. He also conducts research into UFOs.
Education
Knuth was born in Fond du Lac, Wisconsin. He received a Bachelor of Science in physics and mathematics from the University of Wisconsin–Oshkosh in 1988, a Master of Science in physics from Montana State University in 1990, and a PhD in physics (with a minor in mathematics) from the University of Minnesota (1995), where he was supervised by John H. Broadhurst.
Academic career
After receiving his doctorate, Knuth taught in the Department of Speech and Hearing Sciences of the Graduate Center, CUNY, the Departments of Otolaryngology and Neuroscience of the Albert Einstein College of Medicine, and the Department of Physiology and Biophysics of the Cornell University Medical Center from 1997 to 2000. He also worked as a researcher at the Nathan Kline Institute for Psychiatric Research from 1999 to 2001 and at NASA's Ames Research Center from 2001 to 2005. He became an assistant professor of physics at the University at Albany in 2005, was promoted to associate professor in 2009 and to professor in 2023.
He has been editor-in-chief of the MDPI journal Entropy since 2012.
UFO research
Knuth has been quoted in the media on the topic of UFOs. He serves as vice president of UAPx, a nonprofit organization that aims to conduct field research about UFOs, sometimes referred to as UAP, and is a research affiliate of The Galileo Project for the systematic scientific search for evidence of extraterrestrial technological artifacts at Harvard University.
References
External links
Knuth Information Physics Lab
UAPx Nonprofit UAP research organization
1965 births
Quantum physicists
Theoretical physicists
American astrophysicists
Year of birth missing (living people)
Living people
Ufologists
University of Minnesota alumni
Montana State University alumni
University of Wisconsin–Oshkosh alumni
People from Fond du Lac, Wisconsin
American biophysicists
Academic journal editors
University at Albany, SUNY faculty | Kevin Knuth | [
"Physics"
] | 433 | [
"Theoretical physics",
"Quantum physicists",
"Theoretical physicists",
"Quantum mechanics"
] |
71,358,321 | https://en.wikipedia.org/wiki/Precision%20BioSciences | Precision BioSciences, Inc. is a publicly traded American clinical stage gene editing company headquartered in Durham, North Carolina. Founded in 2006, Precision is focused on developing both in vivo and ex vivo gene editing therapies using its proprietary "ARCUS" genome editing platform.
History
Derek Jantz and Jeff Smith met as postdoctoral fellows at Duke University, and in March 2006, they founded Precision BioSciences along with Matt Kane, a student at the Duke Fuqua School of Business at the time. The company went through two rounds of early funding: a Series A round led by venBio to fund development of the genome editing platform, and Series B financing to fund product development efforts. The company completed its initial public offering in 2019, and trades under the Nasdaq ticker DTIL.
Precision entered into a partnership with Eli Lilly in November 2020 to use ARCUS editing for up to six in vivo targets connected to genetic disorders, beginning with Duchenne muscular dystrophy. In September 2021, Precision announced two more collaborations, with UK biotechnology company Tiziana Life Sciences to explore using foralumab to aid chimeric antigen receptor (CAR) T cell therapy, and with Philadelphia-based iECURE to advance candidates into clinical trials and investigate how ARCUS can help treat liver diseases. Michael Amoroso, the former CEO of cell and gene therapy developer Abeona Therapeutics, succeeded Matt Kane as President and CEO in October 2021. That December, Precision announced its entry into an agreement with a syndicate of investors led by ACCELR8 to spin off its subsidiary, Elo Life Systems, and create an independent company focused on food and agriculture business.
ARCUS genome editing
Precision BioSciences' proprietary technology is the ARCUS platform and ARCUS nucleases. ARCUS nucleases are based on a naturally occurring genome editing enzyme, I-CreI, a homing endonuclease that evolved in the algae Chlamydomonas reinhardtii to make highly specific cuts and DNA insertions in cellular DNA. The nuclease is able to deactivate itself once gene edits are made, which minimizes potential off-targeting. An ARCUS nuclease is also much smaller in size than CRISPR spCas9. It can use either adeno-associated virus (AAV) vectors or lipid nanoparticles (LNPs) for delivery to specific tissues and cells. Precision has used ARCUS nucleases to develop multiple ex vivo allogeneic, "off-the-shelf" CAR T cell immunotherapies in early-stage clinical trials. The company also uses ARCUS for in vivo gene editing programs, some of which are in preclinical development as of May 2022.
Similar to I-CreI, ARCUS nucleases generate a unique cleavage site in DNA that is characterized by four-base-pair, 3' overhangs. ARCUS nucleases can perform a range of complex edits, including gene insertion, gene excision, and gene repair. ARCUS nucleases are able to enact all editing operations in one step, which enables efficient multiplexing of edits.
Precision has demonstrated some additional applications of the ARCUS platform, including treating ornithine transcarbamylase deficiency in newborn nonhuman primates and in the use of a LNP to treat chronic Hepatitis B. The company is also pursuing PBGENE-PCSK9, a candidate to treat familial hypercholesterolemia, and PBGENE-PH1, a candidate to treat primary hyperoxaluria type 1.
Clinical trials
Precision is in the process of developing multiple candidates targeting non-Hodgkin lymphoma, acute lymphoblastic leukemia (ALL), and multiple myeloma. The company's lead candidate targeting CD19, PBCAR0191, received orphan drug designation from the U.S. Food and Drug Administration for the treatment of ALL and mantle cell lymphoma, an aggressive subtype of non-Hodgkin lymphoma, as well as fast track designation for the treatment of B-cell ALL. PBCAR0191 began its Phase 1/2a clinical trial of adult subjects in March 2019. In June 2022, Precision reported a 100% response rate, a 73% complete response rate, and a 50% durable response rate, and the company sought to increase enrollment in the study.
Precision is also developing PBCAR19B as an anti-CD19 stealth cell candidate that employs a single gene edit to knock down beta-2 microglobulin, for which a Phase 1 study began in June 2021. The company is also conducting a Phase 1/2a clinical trial evaluating PBCAR269A, its investigational allogeneic B-cell maturation antigen-targeted CAR T cell therapy, for the treatment of multiple myleloma. PBCAR269A began its Phase 1 trials in April 2020, and as of July 2022 had moved onto recruitment for its Phase 1/2a study, which features PBCAR269A in combination with nirogacestat, a gamma secretase inhibitor. In 2020, the FDA granted fast track designation to PBCAR269A for the treatment of relapsed or refractory multiple myeloma, having previously provided orphan drug designation.
References
External links
2006 establishments in North Carolina
2019 initial public offerings
American companies established in 2006
Biotechnology companies of the United States
Clinical trial organizations
Companies based in Durham, North Carolina
Companies listed on the Nasdaq
Gene therapy
Life sciences industry
Pharmaceutical companies established in 2006
Pharmaceutical companies of the United States
Health care companies based in North Carolina | Precision BioSciences | [
"Engineering",
"Biology"
] | 1,182 | [
"Life sciences industry",
"Gene therapy",
"Genetic engineering"
] |
71,359,074 | https://en.wikipedia.org/wiki/Lunar%20Cruiser | The Lunar Cruiser is the nickname of a crewed pressurized lunar rover being developed jointly by JAXA and Toyota that astronauts can drive and live on the Moon.
Mobile Habitat
The Lunar Cruiser is being developed as a part of NASA's Artemis program and will enable astronaut crews to take trips across the Moon lasting up to 30-45 days, live independently from the station by using its life support system as a backup. Named after the Toyota Land Cruiser, its name was chosen "because of the familiar feeling it offers the people involved in the development and manufacture of the vehicle prototype as part of the joint research project as well as the familiarity it will provide the general public." The rover is currently being manufactured, with an expected launch date no earlier than 2032. The rover itself will use fuel-cell electric-vehicle technologies. An update by the development team in late 2023 indicated the very first cruiser would be deployed along with the first moonbase. Mitsubishi is helping develop the hydrogen electrolysis unit due to its development in new maritime technology.
References
External links
Lunar rovers
Missions to the Moon | Lunar Cruiser | [
"Astronomy"
] | 219 | [
"Astronomy stubs",
"Spacecraft stubs"
] |
71,361,778 | https://en.wikipedia.org/wiki/Prussian%20Formation | The Prussian Formation, previously known as the Amber Formation, is a geologic formation in Prussia, today mostly Kaliningrad Oblast that dates to the Eocene. It holds 90% of the world's amber supply and Baltic amber is found exclusively in the Prussian Formation.
The Prussian Formation is equivalent to the Obukhov Formation of Ukraine and Belarus.
Geological context
In situ Baltic amber is found within the Prussian Formation, with the main amber bearing horizon being referred to as "Blue Earth", so named due to its glauconite content. The formation is exposed in the northern part of the Sambia Peninsula in Kaliningrad.
Different authors have given estimates of 40-47 million years ago and 35-43 million years ago as the age of the Prussian Formation.
Paleobiology
Numerous extinct genera and species of plants and animals have been discovered and scientifically described from inclusions in the Prussian Formation. Inclusions of insects make up over 98% of the animals preserved in the amber, while all other arthropods, annelids, molluscs, nematodes, protozoans contribute less than 0.5% of the animals. Vertebrates are another 0.5% of the animals included and mostly are represented by mammal fur, feathers, and reptiles.
Flora
Fauna
References
Geology of Russia
Amber | Prussian Formation | [
"Physics"
] | 267 | [
"Amorphous solids",
"Unsolved problems in physics",
"Amber"
] |
71,363,002 | https://en.wikipedia.org/wiki/Leucocoprinus%20breviramus | Leucocoprinus breviramus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1982 by the mycologists Helen Vandervort Smith and Nancy S. Weber who classified it as Leucocoprinus breviramus. The specimens studied and documented were collected by Ervin Hillhouse in 1971.
Description
Leucocoprinus breviramus is a small dapperling mushroom with white flesh.
Cap: 3.5–9 cm wide. Starts bulbous and expands to conical or campanulate (bell shaped) and finally flattens out or becomes concave with the cap edges lifting up in maturity. The surface is snow white with a slight yellowish brown tinge in the centre. It is covered with small woolly scales (floccules) which are denser and finer in the centre becoming sparser towards the cap edges, these scales easily rub off and cover the fingers. The striations at the cap margins are only visible when mature. The cap flesh is white and thin (3-4mm) near the stem and thins out more towards the cap edges. Stem: 5.5-8.0 cm long and 3-5mm thick at the top tapering to 10-12mm at the bulbous base. The surface is white and sometimes stains slightly yellow when handled whilst the interior may be hollow, filled or solid. It is covered with similar woolly scales to the cap below the stem ring but is smooth above. The small, white stem ring is located towards the top of the stem (superior) but it usually disappears and may just leave small traces on the stem. Gills: White, crowded and free. Spores: Ovate to elliptical with a small pore. Dextrinoid. 7.5-9.0 (10) x 5.5-6.5 μm. Smell: Slightly musky. Taste: Mild when raw and similar to button mushrooms when cooked.
In Weber's book 'A Field Guide to Southern Mushrooms''' a photograph of this species is included however it appears to be a photo of Leucocoprinus cretaceus so this species may by synonymous considering the very similar description.
Habitat and distribution L. breviramus is scarcely recorded and little known. The specimens studied were gathered in Brazoria county, Texas in 1971 and Washington county, Mississippi in 1979. The mushrooms were reported as fruiting singly or sometimes in small clusters on grass and on wet hay in the Summer and Autumn. They were reported as appearing most prominently during dry summers and appearing a few days after rain.
Edibility
The species is reported to be edible without ill effects even when eaten in large quantities and described as very good, however this report comes from a single individual so should not be relied upon as an indication of safety.
Similar species
Leucocoprinus cepistipes appears similar but L. breviramus is distinguished from it by its pure white appearance and the cap striations which only appear at the cap edges as well as the persistent floccules at the centre of the cap. Additionally the tendency to grow individually rather than in tufts helps distinguish L. breviramus.
Leucocoprinus cretaceus'' fruits in large clusters and has larger spores.
References
breviramus
Fungi described in 1982
Fungus species | Leucocoprinus breviramus | [
"Biology"
] | 696 | [
"Fungi",
"Fungus species"
] |
71,363,144 | https://en.wikipedia.org/wiki/Zeldovich%20spontaneous%20wave | A Zeldovich spontaneous wave, also referred to as Zeldovich gradient mechanism, is a reaction wave that propagates spontaneously in a reacting medium with a nonuniform initial temperature distribution when there is no interaction between different fluid elements. The concept was put forward by Yakov Zeldovich in 1980, based on his earlier work with his coworkers. The spontaneous wave is different from the other two conventional combustion waves, namely the subsonic deflagrations and supersonic detonations. The wave, although strictly speaking unrealistic because gasdynamic effects are neglected, is often cited to explain the yet-unsolved problem of deflagration to detonation transition (DDT).
The mechanism behind the spontaneous wave is readily explained by considering a reaction medium at rest with a nonuniform temperature distribution such that the spatial temperature gradients are small or at least it is not sufficiently large (large temperature gradients will evidently lead to interactions between adjacent fluid elements via heat conduction). Corresponding to each fluid element with a definite temperature value, there is an adiabatic induction period, the time it takes to undergo thermal explosion in the absence of any heat loss mechanism. Thus, each fluid element will undergo thermal explosion at a definite time as if it is isolated from the rest of the gas. A sequence of these successive self-ignitions can be identified as some sort of a reaction front and tracked. The spontaneous wave is influenced by the initial condition and is independent of thermal conductivity and the speed of sound.
Description of the spontaneous reaction wave
Let be the initial temperature distribution, which is non trivial, indicating that chemical reactions at different points in space proceed at different rates. To this distribution, we can associate a function , where is the adiabatic induction period. Now, define in space some surface ; suppose if , then this surface for some constant will be parallel to -plane. Examine the change of position of this surface with the passage of time according to
From this, we can easily extract the direction and the propagation speed of the spontaneous front. The direction of the wave is clearly normal to this surface which is given by and the rate of propagation is just the magnitude of inverse of the gradient of :
Note that adiabatic thermal runaways at different places are not casually connected events and therefore can assume, in principle, any positive value. By comparing with other relevant speeds such as, the deflagration speed, , the sound speed, and the speed of the Chapman–Jouguet detonation wave, , we can identify different regimes:
When , the spontaneous wave is not possible. Suppose a rapid reaction for a fluid element at some time . The spontaneous wave reaches the adjacent element located distance apart from the first one at a time . However, before this wave arrives, heat conduction via the deflagration wave would have arrived and already initiated the chemical reaction. Thus, heat conduction is not negligible for this case and therefore spontaneous wave is not possible.
Consider now the case . The spontaneous wave propagates sufficiently faster so that heat conduction is negligible. Moreover, since , the gas medium has sufficient time to equalize the pressure in that gas motion that arises are always subsonic. The inverse effect of the gas motion on the adiabatic induction period is negligible. Mathematically, this regime is identical to the KPP regime.
Next let us consider the case . The gas pressure does not have enough time to equalize and thus a shock wave forms which after some transient evolution, transitions to a detonation wave. This regime is identified as the Zeldovich's gradient mechanism that explains the DDT.
Finally, consider . This regime is similar to the weak detonation wave (such waves are not observed experimentally in combustion systems, although in principle, it is allowed) in which the pressure behind the wave is smaller than it would be in the Chapman–Jouguet wave.
References
Combustion | Zeldovich spontaneous wave | [
"Chemistry"
] | 804 | [
"Combustion"
] |
71,363,329 | https://en.wikipedia.org/wiki/Leucocoprinus%20flavus | Leucocoprinus flavus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1928 by the Belgian mycologist Maurice Beeli who classified it as Coprinus flavus.
It was reclassified as Leucocoprinus flavus by the Belgian mycologist Paul Heinemann in 1977.
Description
Leucocoprinus flavus is a small yellow dapperling mushroom with thin flesh.
Cap: 1.8-2.7 cm wide. Conical to campanulate (bell shaped). Entirely yellow and covered in a powdery yellow material which sticks to the fingers. The small umbo is deeper in colour than the cap and dries brown. Until dried, striations on the cap are not significant but rather it is smooth and slippery. The cap flesh is thin. Gills: Crowded and free. Pale yellow. Beeli described them as yellow but blackening. Stem: 5–6 cm long and 2mm thick at the top, 3-7mm thick at the bulbous base. Pale yellow or similarly yellow to the cap. Hollow. Sometimes presenting visible mycelium at the base. Persistent yellow stem ring towards the top of the stem (superior). It is membranous and curls upwards. Spores: Ovate to almond shaped or elliptical, without a pore. Dextrinoid. 7.5-9.0 x 3.8-5.3 μm. Beeli described them as grey-purple. Taste: Mild.
Habitat and distribution
L. flavus is scarcely recorded and little known. The specimen studied in 1923 was found on rotting wood in July in Congo. Material studied in 1982 was collected under mixed hardwood trees in Owen county, Indiana.
Similar species
Lepiota flava is described similarly by Beeli though he does not note the powdery yellow coating on the cap. Paul Heinemann considered it to be synonymous in 1977, as did Helen Vandervort Smith and Nancy S. Weber in 1982. However it remains classified as a separate species.
References
Leucocoprinus
Fungi of Africa
Taxa named by Paul Heinemann
Taxa named by Maurice Beeli
Fungi described in 1928
Fungus species | Leucocoprinus flavus | [
"Biology"
] | 458 | [
"Fungi",
"Fungus species"
] |
71,363,596 | https://en.wikipedia.org/wiki/Leucocoprinus%20tricolor | Leucocoprinus tricolor is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1981 by the mycologist Helen Vandervort Smith who classified it as Leucocoprinus tricolor.
Description
Leucocoprinus tricolor is a small dapperling mushroom with thin pale yellow flesh.
Cap: 1.6–6 cm wide. Ovate, campanulate or conical and flattening as it matures often with a distinct umbo but sometimes it is absent. When young, the cap surface is covered in woolly scales (floccose) or scales (squamulose) with the squamules at or around the umbo presenting as greyish brown. The rest of the cap and the squamules coating it are pale yellow. The umbo may present as orange-yellow in immature specimens before turning brown and becoming smooth with age. The cap has distinct grooves or striations towards the cap edges which may present as striate, plicate or sulcate. The cap flesh is very thin and flexible but dry feeling. It is pale yellow and does not discolour with damage. Gills: Crowded and free. Pale yellow and very thin. Stem: 1.5–8 cm long and 2-6mm thick at the top, 6-11mm at the bulbous base. Smooth or sometimes with some fine scales towards the top and woolly tufts below. Lemon yellow at the top and golden yellow at the base. Lower scales have an orange tinge and sometimes discolour greyish-brown with damage or when handling. Stem flesh is also pale yellow. The yellow stem ring is small, membranous, thin and quickly disappears. Spores: Ellipsoid to subglobose with small germ pore. 8-11 x 7.2-9 μm. Taste: Indistinct but texture dry like cotton. Smell: Strong and pungent similar to that of the stinking dapperling, Lepiota cristata which is described as having an unpleasant rubbery or fishy odour.
When specimens are dried the umbo or centre of the cap turns greyish brown whilst the rest of the cap remains pale yellow. The base of the stem is orange or cadmium orange. Occasionally specimens do not present such a distinct three colour effect and remain roughly uniform but develop a grey or tan tint. Grey colours rarely occur when specimens are bruised or dried.
Habitat and distribution
L. tricolor is scarcely recorded and little known. The specimens studied were collected from greenhouses at the University of Michigan Botanical Garden in 1975 as well as in some plant pots either filled with soil or bark in subsequent years. They were growing singly or in clusters. Since botanical gardens host exotic plants from all over the world it is unclear from this study where the species originated from or is native to.
Etymology
The specific epithet tricolor refers to the three colour effect which is noticeable when specimens are dried.
References
Leucocoprinus
Fungi described in 1981
Fungus species | Leucocoprinus tricolor | [
"Biology"
] | 630 | [
"Fungi",
"Fungus species"
] |
71,364,202 | https://en.wikipedia.org/wiki/National%20Collection%20of%20Plant%20Pathogenic%20Bacteria | The National Collection of Plant Pathogenic Bacteria (NCPPB) is a bacterial culture repository hosted and maintained by Fera Science in York, United Kingdom. It specializes in bacterial plant pathogens and related bacteria. The NCPPB maintains over 3,500 strains and cultures which can be ordered online for use in education and research. The service is funded by the UK Government via the Department for Environment, Food and Rural Affairs (Defra) and provides support to the UK Plant Health Service.
The collection began in 1947 when the Lister Institute decided to stop maintaining cultures which were not relevant to human health. These samples were combined with a collection at the Botany School of the University of Cambridge and maintained on behalf of the Agricultural Research Council. When the initial curator and plant pathology pioneer Dr Walter John Dowson retired in 1956 the collection was moved to the Ministry of Agriculture, Fisheries and Food (MAFF), at Harpenden. Also in this year the collection was recognised as being of national importance and was designated a National Collection. Fera Science took responsibility for the collection in 1996 when it was moved to a purpose-built facility near York.
The NCPPB holds samples of bacterial plant pathogens from all over the world as well as closely related organisms such as bacteriophages. They also receive samples to add to the collection which are new or not currently well represented.
References
External links
Official website
Organisations based in the United Kingdom
Bacteria
Collections | National Collection of Plant Pathogenic Bacteria | [
"Biology"
] | 291 | [
"Prokaryotes",
"Microorganisms",
"Bacteria"
] |
71,364,289 | https://en.wikipedia.org/wiki/RR%20Lyncis | RR Lyncis is a star system in the northern constellation of Lynx, abbreviated RR Lyn. It is an eclipsing binary of the Algol type; one of the closest in the northern sky at an estimated distance of approximately 263 light years based on parallax measurements. The system is faintly visible to the naked eye with a combined apparent visual magnitude of 5.53. During the primary eclipse the brightness drops to 6.03, while it decreases to magnitude 5.90 with the secondary eclipse. The system is drifting closer to the Sun with a radial velocity of −12 km/s.
This star was found to have a variable radial velocity by W. S. Adams, based on measurements taken in 1911, which suggested it is a spectroscopic binary system. At the time it was identified as Boss 1607 and Groom 1149. Orbital elements for the binary were first published in 1915 by W. E. Harper. In 1931, C. M. Huffer determined Boss 1607 to be an eclipsing binary, based on a light curve generated using photoelectric measurements. This showed a period of 9.9450 days with a magnitude difference of 1.20 between the components. N. G. Roman in 1949 found this to be a metallic-line star and a possible member of the Ursa Major stream.
In 1960, C. and M. Jaschek published a spectral analysis of RR Lyn that showed hydrogen lines for a star of type A7, a K-line of type A3, and metallic lines of type F0 or cooler. Kh. F. Khaliullin and A. I. Khaliullina in 2002 found that the timing of the primary and secondary eclipses underwent quasi-period oscillations. This may be explained by a third body with a mass 90% of the Sun in orbit with the pair. However, as of 2006 the presence of this object has not been confirmed through spectroscopic measurement.
This is a detached double-lined spectroscopic binary with an orbital period of 9.95 days and a small eccentricity. The orbital plane is inclined at an angle of 87.5°, so both stars are seen to eclipse each other once per orbit. The primary component is a slightly-evolved Am star with 1.9 times the mass and 2.6 times the radius of the Sun. The secondary is an F-type main-sequence star with 1.5 times the mass of the Sun and 1.6 times the Sun's radius. The system exhibits pulsation behavior, most of which is attributed to the secondary. The higher frequency modes are Delta Scuti-type pulsations, while the intermediate frequencies are of the Gamma Doradus type. Lower frequency pulsations may be tidally-excited. The system is about one billion years old.
References
Further reading
F-type main-sequence stars
Am stars
Delta Scuti variables
Gamma Doradus variables
Algol variables
Spectroscopic binaries
Lynx (constellation)
Durchmusterung objects
2291
044691
030651
Lyncis, RR | RR Lyncis | [
"Astronomy"
] | 635 | [
"Lynx (constellation)",
"Constellations"
] |
71,364,629 | https://en.wikipedia.org/wiki/Leucocoprinus%20medioflavus | Leucocoprinus medioflavus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1894 by the French mycologist Jean Louis Émile Boudier who classified it as Lepiota medioflava. Boudier also provided various illustrations of the mushroom in different stages of growth.
In 1976 it was classified as Leucocoprinus medioflavus and as the synonym Leucoagaricus medioflavus by the French mycologist Marcel Bon.
In 1999 the variant Leucocoprinus medioflavus var. niveus was described by the mycologists Vincenzo Migliozzi & Marcello Rava. This is now considered a synonym.
Description
Leucocoprinus medioflavus is a small dapperling mushroom with thin white flesh and a pronounced yellow umbo. Boudier described this mushroom in 1894 as follows:
Cap: 2–3 cm wide. White, striated and with a powdery white coating or finely woolly (tomentose) to silky texture. Bulbous or cylindrical when immature expanding to flat with a depressed centre and a prominent yellow umbo. Cap edges lift upwards when mature. Gills: White, free, crowded. Stem: 4–7 cm tall (including the cap thickness). White but tapers up from the thicker base which is often yellow. The stem ring is in the middle of the stem (median) and curls upwards. The stem is slightly scaly (furfuraceous) above the ring and woolly (tomentose) below. Spore print: White Spores: Equilateral, ovate, obtuse, often filled with a small droplet. 5-6 x 3 μm.
Habitat and distribution
L. medioflavus is scarcely recorded and little known. Boudier's 1894 description says the specimens studied were found in France on moist earth in the heat of June, growing in large numbers inside a nursery greenhouse.
Etymology
The specific epithet medioflavus (originally medioflava) derives from the Latin medio meaning 'in the middle' and flavus meaning yellow, flaxen or blonde. This is a reference to the distinct yellow umbo in the centre of the mushroom.
References
Leucocoprinus
Fungi described in 1894
Fungus species | Leucocoprinus medioflavus | [
"Biology"
] | 488 | [
"Fungi",
"Fungus species"
] |
71,366,072 | https://en.wikipedia.org/wiki/Phacopsis%20oroarcticae | Phacopsis oroarcticae is a species of lichenicolous (lichen-dwelling) fungus in the family Parmeliaceae. It was formally described as a new species in 2010 by Russian mycologist Mikhail P. Zhurbenko. The type specimen was collected from a stony polar desert in the Severnaya Zemlya Archipelago in Central Siberia, where it was found growing on the lobes of the foliose lichen Brodoa oroarctica; the species epithet refers to its host. Infection by the fungus results in bleached, swollen, and sometimes contorted lobes. It is the first Phacopsis species known to have Brodoa as a host.
References
Parmeliaceae
Fungi described in 2010
Fungi of Russia
Lichenicolous fungi
Taxa named by Mikhail Petrovich Zhurbenko
Fungus species | Phacopsis oroarcticae | [
"Biology"
] | 171 | [
"Fungi",
"Fungus species"
] |
71,367,242 | https://en.wikipedia.org/wiki/Phacopsis%20vulpicidae | Phacopsis vulpicidae is a species of lichenicolous (lichen-dwelling) fungus in the family Parmeliaceae. It was formally described as a new species in 2019 by mycologists Mikhail P. Zhurbenko and Paul Diederich. The type specimen was collected by the first author near the headwaters of Ar Khordolyn gol River in Renchinlkhümbe Somon (Khövsgöl Province, Mongolia), at an altitude of . There, in the upper limit of a Larix sibirica forest, the fungus was found growing on the thallus of a ground-dwelling Vulpicida juniperina lichen. The species epithet vulpicidae refers to the genus of its host. Infections by the fungus cause blister-like (bullate) swellings of the host thallus. It is known to occur in arctic and mountain tundra and taiga biomes of Asia, Europe, and North America (Alaska). Its only recorded host is Vulpicida juniperina, and almost all recorded host specimens have been terricolous.
References
Parmeliaceae
Fungi described in 2019
Fungi of Asia
Fungi of Europe
Fungi of North America
Lichenicolous fungi
Taxa named by Mikhail Petrovich Zhurbenko
Taxa named by Paul Diederich
Fungus species | Phacopsis vulpicidae | [
"Biology"
] | 271 | [
"Fungi",
"Fungus species"
] |
71,367,805 | https://en.wikipedia.org/wiki/Burnett%20equations | In continuum mechanics, a branch of mathematics, the Burnett equations are a set of higher-order continuum equations for non-equilibrium flows and the transition regimes where the Navier–Stokes equations do not perform well.
They were derived by the English mathematician D. Burnett.
Series expansion
Series expansion approach
The series expansion technique used to derive the Burnett equations involves expanding the distribution function in the Boltzmann equation as a power series in the Knudsen number :
Here, represents the Maxwell-Boltzmann equilibrium distribution function, dependent on the number density , macroscopic velocity , and temperature . The terms etc., are higher-order corrections that account for non-equilibrium effects, with each subsequent term incorporating higher powers of the Knudsen number .
Derivation
The first-order term in the expansion gives the Navier-Stokes equations, which include terms for viscosity and thermal conductivity. To obtain the Burnett equations, one must retain terms up to second order, corresponding to . The Burnett equations include additional second-order derivatives of velocity, temperature, and density, representing more subtle effects of non-equilibrium gas dynamics.
The Burnett equations can be expressed as:
Here, the "higher-order terms" involve second-order gradients of velocity and temperature, which are absent in the Navier-Stokes equations. These terms become significant in situations with high Knudsen numbers, where the assumptions of the Navier-Stokes framework break down.
Extensions
The Onsager-Burnett Equations, commonly referred to as OBurnett, which form a superset of the Navier-Stokes equations and are
second-order accurate for Knudsen number.
Eq. (1)
Eq. (2)
Derivation
Starting with the Boltzmann equation
See also
Fluid dynamics
Lars Onsager
Non-dimensionalization and scaling of the Navier–Stokes equations
Stokes equations
Chapman–Enskog theory
Navier-Stokes equations
References
Further reading
Continuum mechanics | Burnett equations | [
"Physics"
] | 390 | [
"Classical mechanics",
"Continuum mechanics"
] |
71,367,978 | https://en.wikipedia.org/wiki/Hans%20Max%20Jahn | Hans Max Jahn (4 July 1853 – 7 August 1906) was a German physical chemist who worked on thermochemistry and electrochemistry. As an experimental chemist he identified problems in the contemporary theory of electrolyte conductivity and examined the thermodynamic validity of the Gibbs-Helmholtz equation.
Jahn was born in Küstrin (now in Poland) and was educated at the Universities of Berlin and Heidelberg in chemistry and mathematics. His early influences included A. W. von Hofmann whom he assisted as a student, Robert Bunsen, G. Kirchhoff and the mathematician L. Kronecker. After receiving a doctorate in 1875 for work in organic chemistry he became an assistant to Anastassios Christomanos at Athens. In 1877 he moved to Vienna, working under Ernst Ludwig (1842–1915) and in 1884 he moved to Graz. From 1899 he taught at the agricultural school and university in Berlin. Jahn worked with Walther Nernst and one of his experimental result in 1900 was that there was an increased conductivity with increase in concentration of certain electrolytes. This went against the theory that Svante August Arrhenius has proposed and resulted in a major debate.
Jahn married Sophie von Sichrovsky in 1883. Jahn was a keen violinist but suffered from deteriorating hearing. He died in 1906 following complications after an appendictomy.
References
External links
Grundriss der Elektrochemie (1895)
1853 births
1906 deaths
Physical chemists
Electrochemists
Heidelberg University alumni | Hans Max Jahn | [
"Chemistry"
] | 319 | [
"Electrochemistry",
"Electrochemists"
] |
71,368,236 | https://en.wikipedia.org/wiki/Phacopsis%20vulpina | Phacopsis vulpina is a species of lichenicolous (lichen-dwelling) fungus in the family Parmeliaceae, and the type species of the genus Phacopsis. It was formally described as a new species in 1852 by French mycologist Edmond Tulasne. The fungus is restricted to the genus Letharia as a host and consequently has a Northern Hemisphere distribution. Externally, it is somewhat similar in appearance to P. lethariellae, but P. vulpina does not have a brown hypothecium (the area of tissue in the apothecium immediately below the subhymenium).
References
Parmeliaceae
Fungi described in 1852
Taxa named by Edmond Tulasne
Lichenicolous fungi
Fungus species | Phacopsis vulpina | [
"Biology"
] | 156 | [
"Fungi",
"Fungus species"
] |
71,369,165 | https://en.wikipedia.org/wiki/Continuous%20poset | In order theory, a continuous poset is a partially ordered set in which every element is the directed supremum of elements approximating it.
Definitions
Let be two elements of a preordered set . Then we say that approximates , or that is way-below , if the following two equivalent conditions are satisfied.
For any directed set such that , there is a such that .
For any ideal such that , .
If approximates , we write . The approximation relation is a transitive relation that is weaker than the original order, also antisymmetric if is a partially ordered set, but not necessarily a preorder. It is a preorder if and only if satisfies the ascending chain condition.
For any , let
Then is an upper set, and a lower set. If is an upper-semilattice, is a directed set (that is, implies ), and therefore an ideal.
A preordered set is called a continuous preordered set if for any , the subset is directed and .
Properties
The interpolation property
For any two elements of a continuous preordered set , if and only if for any directed set such that , there is a such that . From this follows the interpolation property of the continuous preordered set : for any such that there is a such that .
Continuous dcpos
For any two elements of a continuous dcpo , the following two conditions are equivalent.
and .
For any directed set such that , there is a such that and .
Using this it can be shown that the following stronger interpolation property is true for continuous dcpos. For any such that and , there is a such that and .
For a dcpo , the following conditions are equivalent.
is continuous.
The supremum map from the partially ordered set of ideals of to has a left adjoint.
In this case, the actual left adjoint is
Continuous complete lattices
For any two elements of a complete lattice , if and only if for any subset such that , there is a finite subset such that .
Let be a complete lattice. Then the following conditions are equivalent.
is continuous.
The supremum map from the complete lattice of ideals of to preserves arbitrary infima.
For any family of directed sets of , .
is isomorphic to the image of a Scott-continuous idempotent map on the direct power of arbitrarily many two-point lattices .
A continuous complete lattice is often called a continuous lattice.
Examples
Lattices of open sets
For a topological space , the following conditions are equivalent.
The complete Heyting algebra of open sets of is a continuous complete Heyting algebra.
The sobrification of is a locally compact space (in the sense that every point has a compact local base)
is an exponentiable object in the category of topological spaces. That is, the functor has a right adjoint.
References
External links
Order theory | Continuous poset | [
"Mathematics"
] | 596 | [
"Order theory"
] |
71,369,829 | https://en.wikipedia.org/wiki/Marjorie%20Bick | Marjorie Elizabeth Dulcie Bick (11 December 1915 – 18 October 2013) was an Australian biochemist.
Early life and education
Born the daughter of Charles William Bick of Sandringham, Marjorie studied at Firbank Girl's Grammar School from 1920 and matriculated in 1932 to undertake a Bachelor of Science degree at the University of Melbourne in 1937, then completed a Master of Science Degree at Melbourne in 1941.
Biochemist
Bick began her career as a biochemist at the Walter and Eliza Hall Institute of Medical Research, which beside the Commonwealth Serum Laboratories, was then one of the few institutions offering women in Australia the opportunity of a scientific career. She was amongst a number of notable biochemists, mostly women, like Beryl Splatt and Lorna Silvester who had a major influence on the nation's development of clinical biochemistry, She worked in the field of blood transfusion specialising in the production of blood serum in the laboratory.
In 1939, she was seconded to the Australian Red Cross Society (Victorian Division) Blood Transfusion Services. In 1940, she drove from Melbourne with Sheila Summons, Nancy Hayward and Kathleen Gilles to attend the Science Congress in Canberra where she discussed problems in blood transfusion with the Adelaide committee.
World War Two
Bick was invited to the USA and Canada with Dr Lucy Bryce to study developments in blood transfusion, and worked at Harvard University in the Plasma Fractionation Laboratory. Her research found a direct correlation between the platelet count of human blood, and its vasoconstrictor activity after clotting. Returning to Australia, she became biochemist to the Australian Red Cross Society, overseeing Victoria's Red Cross Blood Bank during WW2, during which she held the rank of captain in the Australian Army Medical Corps.
By 1944, she was Honorary Director of Training and Equipment at the Blood Bank in the Royal Melbourne Hospital and traveled again with Dr Bryce to study in America. They arrived on the S.S. Kanangoora in March 1945 and visited the Hooper Research Foundation in Los Angeles then traveled to New Orleans and Washington, and attended a conference of the Blood Substitutes Committee of the National Research Council.
Bryce then traveled to investigate clinical methods while Bick stayed on in Boston for eighteen months undertaking laboratory work on plasma fractionation in the Department of Physical Chemistry at Harvard Medical School under Professor Edwin J. Cohn, a pioneer in the field. She and Bryce reported on war conditions and attitudes to Australia in America and on the mass production methods at the Cutter Laboratories of packing and shipping plasma and whole blood to be parachuted into the Pacific war zones. Their research coincided with a plan to expand the Blood Bank into a new floor of the Royal Melbourne Hospital.
Post-war career
In 1949, Bick concluded nine years of work for the Red Cross Blood Transfusion Service and joined the Alfred Hospital as a Senior Biochemist where she oversaw the management and implementation of new laboratory procedures at the Hospital. Recipient of a Fulbright Scholarship in 1955, she studied new techniques in the USA at the Massachusetts General Hospital, Boston, and in the United Kingdom at the Isotope School of the Atomic Energy Commission and at University College, London.
Bick was a founding member and Victorian representative 1961–1963 of the Australasian Association of Clinical Biochemists (AACB) which was established 26 May 1961 during an ANZAAS Congress in Brisbane.
Bick then pursued her interest in environmental science and was awarded a Research Scholarship for research at the National Institute of Environmental Health in North Carolina 1967–1969, and then 1969–1971 worked as a biochemist at the Medical Research Council, Division of Clinical Chemistry, in the United Kingdom, publishing on the effect of human exposure to pesticides and to hydrocarbons. Her analysis by gas-liquid chromatography of biopsy specimens of human body fat collected in 1965 from 53 individuals found DDT-derived material and dieldrin present in all samples; a mean concentration of total DDT equivalent stored was 1.81 ppm, and the mean concentration of dieldrin was 0.046 ppm. In other investigations she found that occupational exposure to esterase inhibitors used as pesticides in a group of orchardists, when spraying with reasonable care, is sufficient to cause a decrease in red-cell acetylcholinesterase activity.
Bick returned to Australia in 1972 and worked in Pre-Clinical Drug Evaluation at the Department of Health in Canberra and during the 1970s and 80s contributed to Drug Toxicity Evaluation at the Therapeutic Goods Administration.
Personal life
In the 1950s, Bick was a member and secretary of the first all-women sailing club, The Victorian Ladies' Yacht Club. Retired in 1980, Bick ran a Victorian country Post Office and general store, later living in Canberra and then Brighton. She died on 18 October 2013.
Publications
References
1915 births
2013 deaths
Australian biochemists
Australian scientists
Environmental scientists
WEHI staff
University of Melbourne alumni
20th-century Australian women scientists
Military personnel from Melbourne
Royal Australian Army Medical Corps officers
Australian Army personnel of World War II
Scientists from Melbourne | Marjorie Bick | [
"Environmental_science"
] | 1,017 | [
"Environmental scientists",
"Australian environmental scientists"
] |
71,369,834 | https://en.wikipedia.org/wiki/Sacrifice%20to%20Heaven | Sacrifice to Heaven () is an Asian religious practice originating in the worship of Shangdi in China. In Ancient Chinese society, nobles of all levels constructed altars for Heaven. At first, only nobles could worship Shangdi but later beliefs changed and everyone could worship Shangdi.
Modern Confucian churches make this practice available to all believers and it continues in China without a monarch.
It has been influential on areas outside of China including Japan, Vietnam, and Korea.
The Jì () in the Chinese name is the same Je as in Jesa.
History
It first originated in the Shang dynasty. During the Zhou dynasty, Sacrifice to Heaven and Fen Shan, were privileges enjoyed exclusively by the Son of Heaven due to Shendao teachings.
The rites have been performed at the Temple of Heaven since the Ming dynasty and are still performed today
Some scholars believe that Qing involvement with the ritual standardized Manchu rituals with the book of Manchu rites, but this is unsupported
Since the early years of the Republic of China, Kang Youwei's Confucian movement advocated the separation of Religious Confucianism from the state bureaucracy, allowing everyone to Sacrifice to Heaven according to the Christian model.
In the 21st century, it is done without a monarch. It is sometimes done in other locations aside from the Temple of Heaven, such as in Fujian in 2015
In Korea
In Korea, Sacrifice to Heaven is read as Jecheon (Hanja: 祭天). It is also identified with the word yeonggo 영고 (迎鼓) and has a history linked to Korean shamanism, in addition to Chinese influence.
In Buyeo, during the yeonggo festival which was held in December, prisoners would be released and judgments given. It was used as a political tool. in a manner similar to a jubilee.
These ceremonies were typically characterized by communal and thanksgiving aspects and in Buyeo, it was done after the harvest.
Dongye
Mucheon (舞天), a religious ritual and a comprehensive art form of the Dongye, was an event held during the first month of the lunar calendar (October) in which offerings were made to the heavens and people climbed high mountains to have fun. According to a commentary called the Touyuan Booklet (兎園策府), included in the Dunhuang manuscripts during the Tang Dynasty in China, Mucheon was a custom in Gojoseon that was held in October.
Goryeo
During the Goryeo Dynasty, there was a Jecheon event called Eight Gwanhoe (팔관회/八關會). It was a successor to Silla's Eight Gwanhoe, an event where sacrifices were made to the spirits of all things and the heavens.
There was also an event called Weonguje (圜丘祭), which came from China. According to the Goryeo History, it was practiced from the time of Goryeo Seongjong, and it is said that the Weongudan (圜丘壇) was built to offer sacrifices to the sky. As a place to offer sacrifices to the heavens, Weongudan was repeatedly installed and abolished from the Goryeo Dynasty.
Joseon
During the early Joseon Dynasty, Sejo (世祖), a temple was built and the Sacrifices to Heaven were held, but it was discontinued after seven years. The reasoning was that only the emperor could offer sacrifices to the heavens, and Joseon, as an imperial state, had no such authority as per little China ideology. Later, after the country was renamed the Korean Empire, the practice was restored and a Hwangudan was built for the purpose.
Japan
The ritual of was imported from China to Japan during the Tang Dynasty. The emperor would perform the sacrifice on the winter solstice. According to the book Shoku Nihongi (Japanese: 続日本紀), Emperor Shōmu performed a ritual sacrifice to the heavens during the summer court ceremony (the first day of the New Year, year 725).
The religions of Japan have been heavily influenced by imported beliefs such as Confucianism and Buddhism, which were merged with the country's indigenous religion of Shinto. The Sun Goddess Amaterasu is considered the supreme deity in Japan and is considered the ancestor of both the Emperor and the country. The Emperors were known to build temples and perform sacrifices, leading to the localization of these rituals into the worship of the Sun Goddess at the Ise Shrine.
During the Heian period, Buddhism became deeply ingrained in Japanese society, with the theory of "Honji suijaku" being propagated by the Japanese Royal Family. This theory posited that Buddha was the original deity and that the gods were simply temporary manifestations of the Buddha. According to this theory, the Sun Goddess was seen as an incarnation of Vairocana.
The Shoku Nihongi records that in 698, Emperor Monmu ordered the construction of a temple in the Watarai district of Ise, to worship both gods and Buddha. Over time, the rituals of worshiping the gods took on the characteristics of worshiping the Buddha.
Emperor Kanmu played a pivotal role in centralizing power and establishing the supremacy of the emperor in Japan. In 784, he relocated the capital to Nagaoka-kyō in order to counteract the growing influence of Buddhism in the Nara region and to promote the study of Chinese Confucian texts, such as the Spring and Autumn Annals, among the population. Therefore, he performed a sacrifice to heaven in 785 on the Winter Solstice to assert his authority
The modern concept emerged in Japan in the Meiji period with the rise of western style Japanese nationalism and its promotion by the Imperial House of Japan. Sacrifice to Heaven is still performed but it is considered a form of Shinto. Every year, the festival of Niiname-no-Matsuri (新嘗祭) is performed. Most Japanese citizens are unaware of the connection to China. The first such festival of the reign of an Emperor is called the Daijosai.
Vietnam
In Vietnam, tế thiên or Sacrifice to Heaven was first established with the Đinh dynasty when Đinh Bộ Lĩnh declared himself Emperor. The Đại Việt sử ký toàn thư records an early sacrifice by Lý Anh Tông in 1154.
It is better known in Vietnam by the name Nam Giao.
From the Lý dynasty onwards, the ritual was seen as highly important.
Nam Giao is considered the most important sacrificial ritual of the Nguyễn dynasty and is the only well-documented one
In the Nguyễn dynasty, the Esplanade of Sacrifice to the Heaven and Earth was made to sacrifice to heaven It was made in 1807 and continuous sacrifices were made at it until 1945 The Nam Giao sacrifice ceremony was gradually restored to be included in Festival Huế every two years from 2002 and continues to this day.
See also
Temple of Heaven
Wufang Shangdi
Ancestor veneration in China
Tian
Son of Heaven
Jesa
Feng Shan
Interactions Between Heaven and Mankind
Unity of Heaven and humanity
Tenno taitei
Shangdi
References
Pages with unreviewed translations
Confucian rites
Relationship between Heaven and Mankind
Ritual
Sacrifice | Sacrifice to Heaven | [
"Biology"
] | 1,459 | [
"Behavior",
"Human behavior",
"Ritual"
] |
71,369,861 | https://en.wikipedia.org/wiki/Leucocoprinus%20brunnescens | Leucocoprinus brunnescens is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1904 by the American mycologist Charles Horton Peck who classified it as Lepiota brunnescens.
In 1945 it was classified as Leucocoprinus brunnescens by the French mycologist Marcel Locquin.
It was briefly classified as Leucoagaricus brunnescens by the French mycologist Marcel Bon in 1981 before again being reclassified as Leucocoprinus brunnescens in 1983 by the British mycologist David Pegler.
Description
Leucocoprinus brunnescens is a small dapperling mushroom with thin white flesh.
Cap: 2-3cm. Convex or flat with an umbo. Whitish colour with brown specks or scales (squamules) forming on the cap except in the centre. The cap flesh is thin and the edges may develop cracks. Stem: 3-5cm long and 2-4mm thick. White, hollow and fibrous with a slightly thicker base. Small persistent annulus in the middle of the stem (median). Gills: White, crowded and free. Spores: Elliptical, 6-8 x 4-5 μm. Taste: Sweet.
The flesh bruises brown with discolouration also presenting when dry with the stem below the stem ring at first turning reddish-brown before becoming brown. Peck notes that within 12-24 hours the entire drying mushroom turns brown.
Locquin's 1945 description varies in that it notes pink gills bordered with black. It's possible that this is a description of the drying mushroom or it may be another species as Locquin was likely aware of given his note of 'L. brunnescens Peck ?'
Habitat and distribution
L. brunnescens is scarcely recorded and little known. Peck's 1904 study was on specimens found in open woods and grass near St. Louis, Missouri in July through August whilst Pegler's study was on species in the Antilles islands of the Caribbean.
Etymology
The specific epithet brunnescens is Latin for 'brownish' or 'browning'. This is a reference to the brown discolouration of this mushroom.
References
Leucocoprinus
Fungi described in 1904
Taxa named by Charles Horton Peck
Fungus species
Fungi of North America | Leucocoprinus brunnescens | [
"Biology"
] | 485 | [
"Fungi",
"Fungus species"
] |
71,370,323 | https://en.wikipedia.org/wiki/Leucocoprinus%20castroi | Leucocoprinus castroi is a species of mushroom-producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 2003 by the mycologist Jaime Bernardo Blanco-Dios who classified it as Leucocoprinus castroi.
Description
Leucocoprinus castroi is a small dapperling mushroom with thin white flesh.
Cap: Usually 2–3.5cm wide, 5cm in the largest specimens. It starts elliptical or conical expanding to campanulate (bell shaped) and finally flat or concave and is very fragile. The surface is uniformly yellow when young but in maturity it has yellow or orange striations with white grooves between running from the cap edge up to the edge of the centre disc, which is yellow to brownish-ochre in colour. The cap is covered in woolly scales (floccose) which are white in the grooves, yellow to brown in the centre disc and yellow to orange elsewhere. Stem: Usually 4.8–8.3cm tall, up to 9.5cm in the tallest specimens. 0.15–0.7mm thick. Yellow to greenish in the top half of the stem becoming paler towards the base with whitish ochre tones. Fragile and hollow and covered in white woolly scales. Sometimes bulging in the middle of the stem. The beige or yellow, membranous stem ring is located towards the top of the stem (superior) and may disappear. It is similarly scaly to the stem. Gills: Whitish, crowded and free. Spores: Ellipsoid with a germ pore. Dextrinoid. 8.5–11.5 x 6.5–8.5 μm. Smell: Pleasant and like aniseed at the cap but like Scleroderma at the base. Taste: Mushroomy.
Habitat and distribution
L. castroi is scarcely recorded and little known. It has been found in coastal and subcoastal forests of Pinus pinaster trees in the Galicia region of Spain. It is one of the few Leucocoprinus species documented as growing outside in the wild in Europe since most species in this genus are tropical and only spread via human activity outside of tropical regions.
Etymology
The specific epithet castroi is named for the Spanish mycologist María Luisa Castro in recognition of her study of mycology in Galicia.
References
castroi
Fungi of Spain
Fungi described in 2003
Fungus species | Leucocoprinus castroi | [
"Biology"
] | 498 | [
"Fungi",
"Fungus species"
] |
69,783,652 | https://en.wikipedia.org/wiki/Belkis%20Valdman | Belkis Valdman (5 May 1942 – 1 August 2011) was a Turkish-born naturalised Brazilian researcher, teacher and academic chemical engineer, who worked in the field of instrumentation and process control in chemical engineering.
Early life and education
Belkis Valdman was born in Turkey on 5 May 1942, the daughter of Moise Dwek and Esterina Duek (née Saragossy), one of three children, and became a naturalised Brazilian citizen in 1967.
She graduated in chemical engineering in 1966 from the then National School of Chemistry of the University of Brazil, now the School of Chemistry at Universidade Federal do Rio de Janeiro (UFRJ), where she began teaching in March of the following year. In 1968, she earned a master's degree in chemical engineering from UFRJ. In 1969, she obtained a master's degree in chemical engineering from the University of Manchester, then earned a PhD degree in chemical engineering there in 1976. She carried out post-doctoral studies in the area of bioprocesses at the Universidade Autônoma de Barcelona in 1993.
Career
She held the positions of director of the Escola de Química (School of Chemistry) at the Federal University of Rio de Janeiro, later becoming pro-rector of graduation there. She was a member of the Brazilian Institute of Oil, Gas and Biofuels.
A professor at UFRJ since 1968, Valdman became a full professor in 1992, having taken on a number of significant positions within the university during her academic career. She was coordinator of post-graduate studies at the School of Chemistry (1988–1990), head of the Department of Chemical Engineering (1983–1989), director of the School of Chemistry (2002 to 2006), a member of the University Council (2003 to 2011) and pro-rector of undergraduate studies (2007–2011) during Aloisio Teixeira's second term as rector. Her management as pro-rector was characterised by a large expansion in the opportunities for a wider group of students to study at the university. Valdman was a supporter of the introduction of the Exame Nacional do Ensino Médio (National High School Exam) as a form of selection for undergraduate courses, by allowing any candidate from all over the country and from any social class to become a student at Federal University of Rio de Janeiro.
Areas of research
Belkis Valdman's research fields included
Modeling and simulation of processes and control systems;
Integrated digital systems for simulation, control and optimization of processes;
Development of biosensors for monitoring and detection components;
Development of special sensors for monitoring and control of bioprocesses.
Awards and recognition
1981 – became a member of the Instrumentation and Automation Commission of the Brazilian Petroleum Institute
1990 – made a Pesquisador IB by the National Council for Scientific and Technological Development (CNPq)
1985 and 1991 – received the Prêmio Bristol de Instrumentação do Instituto Brasileiro de Petróleo, Gás e Biocombustíveis (IBP) award
2007– the Assembléia Legislativa do Estado do Rio de Janeiro honoured Valdman for her services to the state of Rio de Janeiro and to the country of Brazil.
Personal life
Belkis Valdman died on 1 August 2011 at São Lucas Hospital in Rio de Janeiro, and was buried at the Jewish Cemitério Israelita do Caju the following day.
Selected publications
Valdman B. "Dinamica e Controle de Processos" (1998) 1ªEd., (1999) 2ª Ed., Editora TÓRCULO Art. Gráficas S. A., Santiago de Compostela, España.
Bojorge N., Valdman B., Acevedo F., Gentina J.C. "A semi-structured model for the growth and B-galactosidase production by fed-batch fermentation of Kluyveromyces marxianus" (1999), Bioprocess Engineering, 21, (4), 313–318.
Salgado A M, Folly ROM, Valdman B., Valero F. "Desenvolvimento de um Biosensor Enzimático para Monitoração de Sacarose" (1999), Memórias del II Curso Int. Biotecnologia Industrial, Univ. Autonoma Metropo;itana – UAM, México, v. I, 1–4.
Salgado A.M., Folly R.OM., Valdman B. "Biomass monitoring by use of a continuous on-line optical sensor" (2001) Sensors & Actuators B: Chemical, V.75/1-2, 24–28.
Valdman, B. "Dinâmica e Controle de Processos" 2a. ed. 1999, 3a.Ed. 2000, Santiago de Compostela: Editora Tórculo Art. Gráficas Ltda., v.1. p. 225.
Salgado A M., Folly R.O M., Valdman B., Cos D., Valero F. "Colorimetric method for the determination of ethanol by Flow Injection Analysis" (2000), Biotechnology Techniques, 22, (4), 327–330.
Salgado A M., Folly R. O M., Valdman B., Valero F. "Desenvolvimento de um Biosensor Enzimático para Monitoração de Sacarose" (2000) Anais II Simp. Nac. Instrumentação Agropecuária, Ed. Embrapa, São Carlos, BR, v.I, 81–85.
References
Brazilian chemical engineers
Federal University of Rio de Janeiro
Federal University of Rio de Janeiro alumni
Academic staff of the Federal University of Rio de Janeiro
2011 deaths
1942 births
Women chemical engineers
Brazilian women engineers
20th-century Brazilian engineers
21st-century Brazilian engineers | Belkis Valdman | [
"Chemistry"
] | 1,218 | [
"Women chemical engineers",
"Chemical engineers"
] |
69,784,446 | https://en.wikipedia.org/wiki/Lanthanide%20trichloride | Lanthanide trichlorides are a family of inorganic compound with the formula LnCl3, where Ln stands for a lanthanide metal. The trichlorides are standard reagents in applied and academic chemistry of the lanthanides. They exist as anhydrous solids and as hydrates.
Properties
The anhydrous solids have melting points range from ca. 582 (Tb) - 925 °C (Lu). They are generally pale colored, often white. As coordination polymers, they only dissolve in donor solvents, including water.
Preparation
The lanthanide oxides and carbonates dissolve in hydrochloric acid to give chloride salt of the hydrated cations:
M2O3 + 6HCl + n H2O → 2[Ln(H2O)n]Cl3
Industrial routes
Anhydrous trichlorides are produced commercially by carbothermic reaction of the oxide:
M2O3 + 3Cl2 + 3C → 2MCl3 + 3CO
Ammonium chloride route
The ammonium chloride route refers to a general procedure to produce anhydrous lanthanide chlorides. The method has the advantages of being general for the 14 lanthanides and it produces air-stable intermediates that resist hydrolysis. The use of ammonium chloride as a reagent is convenient because the salt is anhydrous, even when handled in air. Ammonium chloride is also attractive because it thermally decomposes to volatile products at temperatures compatible with the stability of the trichloride targets.
Step 1 preparation of ammonium lanthanide chlorides
The reaction of an intimate mixture of lanthanide oxides with excess ammonium chloride produces anhydrous ammonium salts of the penta- and hexachlorides. Typical reaction conditions are hours at 230-250 °C. Some lanthanides (as well as scandium and yttrium) form pentachlorides:
M2O3 + 10NH4Cl → 2(NH4)2MCl5 + 3H2O + 6NH3
(M = Dy, Ho, Er, Tm, Lu, Yb, Y, Sc)
Tb4O7 + 22NH4Cl → 4(NH4)2TbCl5 + 7H2O + 14NH3
Other lanthanides for hexachlorides:
M2O3 + 12NH4Cl → 2(NH4)3MCl6 + 3H2O + 6NH3
(M = La, Ce, Nd, Pm, Sm, Eu, Gd)
Pr6O11 + 40NH4Cl → 6(NH4)3PrCl6 + 11H2O + 22NH3
These reactions can also start with the metals, e.g.:
Y + 5NH4Cl → (NH4)2YCl5 + 1.5H2 + 3NH3
Step 2 thermolysis of ammonium lanthanide chlorides
The ammonium lanthanum chlorides are converted to the trichlorides by heating in a vacuum. Typical reaction temperatures are 350–400 °C:
(NH4)2MCl5 → MCl3 + 2HCl + 2NH3
(NH4)3MCl6 → MCl3 + 3HCl + 3NH3
Other methods
Hydrated lanthanide trichlorides dehydrate under a hot stream of hydrogen chloride.
Structures
As indicated in the table, the anhydrous trichlorides follow two main motifs, UCl3 and YCl3. The UCl3 structure features 9-coordinate metal centers. The PuBr3 structure, adopted uniquely by TbCl3, features 8-coordinated metals. The remaining later metals are 6-coordinate as is aluminium trichloride.
Reactions
Lanthanide trichlorides are commercial precursors to the metals by reduction, e.g. with aluminium:
LnCl3 + Al → Ln + AlCl3
In some cases, the trifluoride is preferred.
They react with humid air to give oxychlorides:
LnCl3 + H2O → LnOCl + 2 HCl
For synthetic chemists, this reaction is a problematic since the oxychlorides are less reactive.
References
Chlorides
Lanthanum compounds
Lanthanide halides | Lanthanide trichloride | [
"Chemistry"
] | 902 | [
"Chlorides",
"Inorganic compounds",
"Salts"
] |
69,787,990 | https://en.wikipedia.org/wiki/Goldberg%20drum | A Goldberg drum is a laboratory equipment used in the studies of aerosols. It was described by Leonard J. Goldberg from the Naval Biological Laboratory, School of Public Health, University of California, Berkeley, in 1958. It is used to contain airborne aerosols and particles.
References
Aerosols
Laboratory equipment | Goldberg drum | [
"Chemistry"
] | 64 | [
"Aerosols",
"Colloids"
] |
69,791,721 | https://en.wikipedia.org/wiki/Candolleomyces%20candolleanus | Candolleomyces candolleanus (formerly known as Psathyrella candolleana) is a mushroom in the family Psathyrellaceae. It is commonly found growing in small groups around stumps and tree roots on lawns and pastures in Europe and North America. In 2014, it was reported from Iraq. The coloring varies between white and golden brown.
Description
The cap is tan when young, growing to in diameter, initially conical, later becoming rounded and finally with upturned margins in maturity. The cap margin is irregular and radially asymmetrical—a defining characteristic of this species. It can retain veil fragments on the edge and center. The white stalk is tall and 3–7 mm wide. The spore print is purple-brown, while spores are smooth and elliptical, measuring 6.5–8 by 4–5 μm.
Etymology
The specific epithet candolleanus honors Swiss botanist Augustin Pyramus de Candolle.
Edibility
While it is edible and may have a good flavor, it is not recommended due to its thin flesh, alleged poor culinary value and consistency, as well as difficulty in identification.
Similar species
One similar species is Psathyrella gracilis. Some species may have darker caps when young, drying to match that of C. candolleanus.
See also
List of Psathyrella species
References
External links
Psathyrellaceae
Edible fungi
Fungi described in 1818
Fungi of Asia
Fungi of Europe
Fungi of North America
Taxa named by Elias Magnus Fries
Fungus species | Candolleomyces candolleanus | [
"Biology"
] | 309 | [
"Fungi",
"Fungus species"
] |
69,796,600 | https://en.wikipedia.org/wiki/Curium%28III%29%20chloride | Curium(III) chloride is the chemical compound with the formula CmCl3.
Structure
Curium(III) chloride has a 9 coordinate tricapped trigonal prismatic geometry.
Synthesis
Curium(III) chloride can be obtained from the reaction of hydrogen chloride gas with curium dioxide, curium(III) oxide, or curium(III) oxychloride at a temperature of 400-600 °C:
It can also be obtained from the dissolution of metallic curium in dilute hydrochloric acid:
This method has a number of disadvantages associated with the ongoing processes of hydrolysis and hydration of the resulting compound in an aqueous solution, making it problematic to obtain a pure product using this reaction.
It can be obtained from the reaction of curium nitride with cadmium chloride:
References
Curium compounds
Nuclear materials
Chlorides
Actinide halides | Curium(III) chloride | [
"Physics",
"Chemistry"
] | 181 | [
"Chlorides",
"Inorganic compounds",
"Salts",
"Inorganic compound stubs",
"Materials",
"Nuclear materials",
"Matter"
] |
69,797,343 | https://en.wikipedia.org/wiki/Dimitris%20Koukoulopoulos | Dimitris Koukoulopoulos (born 1984) is a Greek mathematician working in analytic number theory as a professor at the University of Montreal.
In 2019, in joint work with James Maynard, he proved the Duffin-Schaeffer conjecture.
He was an invited speaker at the 2022 International Congress of Mathematicians.
Publications
References
Living people
1984 births
21st-century Greek mathematicians
Number theorists
Complex analysts
Academic staff of the Université de Montréal
Greek emigrants to Canada | Dimitris Koukoulopoulos | [
"Mathematics"
] | 93 | [
"Number theorists",
"Number theory"
] |
69,797,720 | https://en.wikipedia.org/wiki/Pixel%20Fold | The Pixel Fold is an Android-powered foldable smartphone designed, developed, and marketed by Google as part of the Google Pixel product line. It was officially announced on May 10, 2023, at the annual Google I/O keynote, and was released in the United States on June 28. Reception was mixed, with many critics praising the phone's cameras and overall design but criticizing the price, durability, weight, and inner display.
History
In May 2019, then-Pixel product lead Mario Queiroz revealed that a foldable smartphone was in early development at Google's hardware division. However, the company had no immediate plans to bring said phone to the market. The company had previously filed a patent for an unknown foldable display in March. By August 2020, an Android-powered Pixel foldable was in active development, with the codename "Passport" and a planned launch date of late 2021. This had been delayed to 2022 by November 2021, with the device now codenamed "Pipit". Shortly thereafter, Google abandoned its plans for a Pixel foldable due to increased competition from other smartphone manufacturers, before restarting production by January 2022. 9to5Google reported "Pixel Notepad" as a potential name for the device, with "Pixel Logbook" previously being considered. In September 2022, The New York Times reported that Google was "exploring" a foldable phone with a targeted release date of 2023; by then, Google was working on the third iteration of the Pixel foldable, now codenamed "Felix". Google designer Ivy Ross later explained that Google had held off releasing the foldable for so long because they felt prototype models had not been "good enough yet".
CNBC reported the device's name to be the "Pixel Fold" in April 2023, asserting that it would be similar to Samsung's Galaxy Z Fold series in terms of specifications and pricing. The phone was reported to be powered by the second-generation Tensor system-on-a-chip and be the most expensive entry in Google's Pixel lineup yet. The device was approved by the Federal Communications Commission in May, ahead of its imminent launch. On May 4, Google confirmed the device's existence on social media, revealing its full design and teasing an announcement at the forthcoming Google I/O keynote. The company unveiled the Pixel Fold at I/O on May 10 accordingly, with pre-orders available immediately at the online Google Store. With the Fold's launch, Apple became the only major smartphone brand without a foldable offering. Other wireless carriers began pre-orders in late June. it became available in four countries on June 28. Days after receiving their devices, many buyers reported that their screens had broken.
Specifications
Design
The Pixel Fold is available in two colors:
Hardware
The Pixel Fold has a display, which opens vertically to reveal a display. At launch, it was the shortest and widest Pixel phone, and the thinnest foldable smartphone on the market. The exterior screen is edge-to-edge, akin to regular smartphones, while the interior screen has slim black bezels. Both displays have a 120 Hz variable refresh rate, while the phone's battery size of 4821 mAh is the largest amongst foldables in the U.S. It is available in 256 or 512 GB of storage and 12 GB of RAM. Google markets the phone as having the "most durable hinge on a foldable". It is equipped with a total of five cameras, with three on the back, one on the front, and one on the inside. The three rear cameras include a 48 megapixel wide lens, a 10.8 megapixel ultrawide lens, and a 10.8 megapixel telephoto lens; the front camera has a 9.5 megapixel sensor, while the inner camera has an 8 megapixel sensor.
Software
The Pixel Fold shipped with Android 13.
Marketing
Ahead of its launch at I/O in May 2023, the Pixel Fold was included in a commercial starring NBA and WNBA athletes. In June, the Pixel Fold and Pixel 7 Pro were featured in a series of comparative advertisements targeting the iPhone.
Reception
Critical reception to the Pixel Fold was decidedly mixed. Ron Amadeo of Ars Technica gave the phone high praise, deeming it vastly superior to the competition. Chris Wedel of XDA Developers called it a respectable first attempt from Google, praising the Fold's compact design, cameras, and software. Engadget Sam Rutherford agreed, also highlighting the phone's design, cameras, and software, while expressing ambivalence over its price and durability. Brian Heater of TechCrunch called it a "well-rounded take on the foldable form factor", but was disappointed that the high price meant it was unlikely to become a "mainstream device".
Writing for Android Police, Will Sattelberg lamented that the Pixel Fold "fails to live up to its full potential", specifically criticizing the quality of the inner display and the phone's durability, or lack thereof. The Washington Post Chris Velazco found it to be a mixed bag, praising its design and cameras but feeling that its shortcomings and lack of uniqueness made the high price "harder to swallow". Samuel Gibbs of The Guardian appreciated the Fold's wider and shorter screen and lauded its cameras, but was less enthusiastic about the software, price, and heaviness. Allison Johnson of The Verge also criticized its price, durability, and heaviness, while finding the camera system versatile and praising the design. Her colleague Dan Seifert opined that the Fold was inferior to Samsung's foldables in various aspects.
Analyst Anshel Sag of Moor Insights & Strategy believed that the Pixel Fold's high price signaled that Google was not seeking to achieve high sales numbers, but rather use the device as a "vessel on which [it] can perfect its foldable software future".
See also
Galaxy Z series
Surface Duo
References
External links
Android (operating system) devices
Foldable smartphones
Google hardware
Google Pixel
Mobile phones introduced in 2023
Mobile phones with 4K video recording
Mobile phones with multiple rear cameras | Pixel Fold | [
"Technology"
] | 1,281 | [
"Crossover devices",
"Foldable smartphones"
] |
69,798,178 | https://en.wikipedia.org/wiki/Cutwidth | In graph theory, the cutwidth of an undirected graph is the smallest integer with the following property: there is an ordering of the vertices of the graph, such that every cut obtained by partitioning the vertices into earlier and later subsets of the ordering is crossed by at most edges. That is, if the vertices are numbered , then for every , the number of edges with and is at most .
The cutwidth of a graph has also been called its folding number. Both the vertex ordering that produces the cutwidth, and the problem of computing this ordering and the cutwidth, have been called minimum cut linear arrangement.
Relation to other parameters
Cutwidth is related to several other width parameters of graphs. In particular, it is always at least as large as the treewidth or pathwidth of the same graph. However, it is at most the pathwidth multiplied by , or the treewidth multiplied by where is the maximum degree and is the number of vertices. If a family of graphs has bounded maximum degree, and its graphs do not contain subdivisions of complete binary trees of unbounded size, then the graphs in the family have bounded cutwidth. In subcubic graphs (graphs of maximum degree three), the cutwidth equals the pathwidth plus one.
The cutwidth is greater than or equal to the minimum bisection number of any graph. This is minimum possible number of edges from one side to another for a partition of the vertices into two subsets of equal size (or as near equal as possible). Any linear layout of a graph, achieving its optimal cutwidth, also provides a bisection with the same number of edges, obtained by partitioning the layout into its first and second halves. The cutwidth is less than or equal to the maximum degree multiplied by the graph bandwidth, the maximum number of steps separating the endpoints of any edge in a linear arrangement chosen to minimize this quantity. Unlike bandwidth, cutwidth is unchanged when edges are subdivided into paths of more than one edge. It is closely related to the "topological bandwidth", the minimum bandwidth that can be obtained by subdividing edges of a given graph. In particular, for any tree it is sandwiched between the topological bandwidth and a slightly larger number, .
Another parameter, defined similarly to cutwidth in terms of numbers of edges spanning cuts in a graph, is the carving width. However, instead of using a linear ordering of vertices and a linear sequence of cuts, as in cutwidth, carving width uses cuts derived from a hierarchical clustering of vertices, making it more closely related to treewidth or branchwidth and less similar to the other width parameters involving linear orderings such as pathwidth or bandwidth.
Cutwidth can be used to provide a lower bound on another parameter, the crossing number, arising in the study of graph drawings. The crossing number of a graph is the minimum number of pairs of edges that intersect, in any drawing of the graph in the plane where each vertex touches only the edges for which it is an endpoint. In graphs of bounded degree, the crossing number is always at least proportional to the square of the cutwidth. A more precise bound, applying to graphs where the degrees are not bounded, is:
Here, the correction term, proportional to the sum of squared degrees, is necessary to account for the existence of planar graphs whose squared cutwidth is proportional to this quantity but whose crossing number is zero. In another style of graph drawing, book embedding, vertices are arranged on a line and edges are arranged without crossings into separate half-plane pages meeting at this line. The page width of a book embedding has been defined as the largest cutwidth of any of the pages, using the same vertex ordering.
Computational complexity
The cutwidth can be found, and a linear layout of optimal width constructed, in time for a tree of vertices. For more general graphs, it is NP-hard. It remains NP-hard even for planar graphs of maximum degree three, and a weighted version of the problem (minimizing the weight of edges across any cut of a linear arrangement) is NP-hard even when the input is a tree.
Cutwidth is one of many problems of optimal linear arrangement that can be solved exactly in time by the Held-Karp algorithm, using dynamic programming. A faster quantum algorithm with time is also known. Additionally, it is fixed-parameter tractable: for any fixed value of , it is possible to test whether a graph has cutwidth at most , and if so find an optimal vertex ordering for it, in linear time. More precisely, in terms of both and , the running time of this algorithm is . An alternative parameterized algorithm, more suitable for graphs in which a small number of vertices have high degree (making the cutwidth large) instead solves the problem in time polynomial in when the graph has a vertex cover of bounded size, by transforming it into an integer programming problem with few variables and polynomial bounds on the variable values. It remains open whether the problem can be solved efficiently for graphs of bounded treewidth, which would subsume both of the parameterizations by cutwidth and vertex cover number.
Cutwidth has a polynomial-time approximation scheme for dense graphs, but for graphs that might not be dense the best approximation ratio known is . This comes from a method of Tom Leighton and Satish Rao for reducing approximate cutwidth to minimum bisection number, losing a factor of in the approximation ratio, by using recursive bisection to order the vertices. Combining this recursive bisection method with another method of Sanjeev Arora, Rao, and Umesh Vazirani for approximating the minimum bisection number, gives the stated approximation ratio. Under the small set expansion hypothesis, it is not possible to achieve a constant approximation ratio.
Applications
An early motivating application for cutwidth involved channel routing in VLSI design, in which components arranged along the top and bottom of a rectangular region of an integrated circuit should be connected by conductors that connect pairs pins attached to the components. If the components are free to be arranged into different left-to-right orders, but the pins of each component must remain contiguous, then this can be translated into a problem of choosing a linear arrangement of a graph with a vertex for each component and an edge for each pin-to-pin connection. The cutwidth of the graph controls the number of channels needed to route the circuit.
In protein engineering, an assumption that an associated graph has bounded cutwidth has been used to speed up the search for mRNA sequences that simultaneously code for a given protein sequence and fold into a given secondary structure.
A weighted variant of the problem applying to directed acyclic graphs, and only allowing linear orderings consistent with the orientation of the graph edges, has been applied to schedule a sequence of computational tasks in a way that minimizes the maximum amount of memory required in the schedule, both for the tasks themselves and to maintain the data used for task-to-task communication. In database theory, the NP-hardness of the cutwidth problem has been used to show that it is also NP-hard to schedule the transfer of blocks of data between a disk and main memory when performing a join, in order to avoid repeated transfers of the same block while fitting the computation within a limited amount of main memory.
In graph drawing, as well as being applied in the lower bound for crossing number, cutwidth has been applied in the study of a specific type of three-dimensional graph drawing, in which the edge are represented as disjoint polygonal chains with at most one bend, the vertices are placed on a line, and all vertices and bend points must have integer coordinates. For drawings of this type, the minimum volume of a bounding box of the drawing must be at least proportional to the cutwidth multiplied by the number of vertices. There always exists a drawing with this volume, with the vertices placed on an axis-parallel line.
References
Graph invariants | Cutwidth | [
"Mathematics"
] | 1,697 | [
"Graph invariants",
"Mathematical relations",
"Graph theory"
] |
69,799,356 | https://en.wikipedia.org/wiki/Wasserwerfer%2010000 | The Wasserwerfer 10000 (WaWe 10, literally "Water Launcher 10000") is a water cannon used for riot control developed by Rosenbauer on the Mercedes-Benz Actros chassis for the Federal Police (Bundespolizei) and Bereitschaftspolizei in Germany. Named for its water capacity, it is the successor to the Wasserwerfer 9000.
History
The need for new water cannons for the federal and state police of Germany was first discussed at the 2005 Innenministerkonferenz; some older Wasserwerfer 9000s, previously criticised for safety concerns, were due to be retired following the 2006 FIFA World Cup that would take place across Germany. Following a tendering process by the Federal Ministry of the Interior's , the contract to build these new water cannons was won by Austrian fire engine manufacturer Rosenbauer in 2008, and development of the Wasserwerfer 10000 commenced.
The first prototype Wasserwerfer 10000 was handed over to the Federal Ministry of the Interior in 2009, and the first production examples were delivered to state police forces in Hamburg, Berlin, Saxony, North Rhine-Westphalia and Baden-Württemberg between 2010 and 2011. The Wasserwerfer 10000 is built on the Mercedes-Benz Actros 3341 tri-axle truck chassis with an armored angular body, preventing rioters from climbing onto the roof and projectiles from damaging it, and is equipped with a polycarbonate shatter-proof windshield. Three spray nozzles aimed with integrated closed-circuit television cameras and controlled by joysticks are positioned on the roof; two on the front and one on the rear of the truck. Loudspeakers are also equipped. The vehicle is operated by a crew of five police officers.
A total of 78 Wasserwerfer 10000s were ordered by police forces across Germany throughout its production run, replacing 117 Wasserwerfer 9000s in a replacement scheme lasting until 2019. As of 2020, following a total of 15 operated by the Bundespolizei, the largest operators of Wasserwerfer 10000s include the states of Hamburg and North Rhine-Westphalia, both operating six of the type, and Berlin and Bavaria, who operate five. Wasserwerfer 10000s have been used in a number of protests and riot control scenarios, including a large deployment at protests during the 2017 G20 Hamburg summit.
The effectiveness of the Wasserwerfer 10000's polycarbonate windshield was questioned in 2014 following an incident in a Thuringia state police training exercise, in which mock rioters damaged the windshield by throwing plastic bottles, eggs and tennis balls at it.
References
Non-lethal weapons
Riot control weapons
Water
Law enforcement in Germany | Wasserwerfer 10000 | [
"Environmental_science"
] | 556 | [
"Water",
"Hydrology"
] |
69,799,974 | https://en.wikipedia.org/wiki/Intestine-on-a-chip | Intestines-on-a-chip (gut-on-a-chip, mini-intestine) are microfluidic bioengineered 3D-models of the real organ, which better mimic physiological features than conventional 3D intestinal organoid culture. A variety of different intestine-on-a-chip models systems have been developed and refined, all holding their individual strengths and weaknesses and collectively holding great promise to the ultimate goal of establishing these systems as reliable high-throughput platforms for drug testing and personalised medicine. The intestine is a highly complex organ system performing a diverse set of vital tasks, from nutrient digestion and absorption, hormone secretion, and immunological processes to neuronal activity, which makes it particularly challenging to model in vitro.
Conventional intestine models
Conventional intestinal models, such as traditional 2D cell culture of immortalised cell lines (e.g. CaCo2 or HT29), transwell cultures, Ussing chambers, and everted gut sacs, have been used extensively to understand better (patho-)physiological processes in the intestine. However, many intestinal functions are difficult to recapitulate and study using such simplistic models. Thus, these systems' translational and experimental value is limited.
In 2009, the development of intestinal organoids marked a milestone in the in vitro modelling of intestinal tissue. Intestinal organoids mimic the in vivo stem cell niche as intestinal stem cells spontaneously give rise to a closed, cystic mini-tissue with outward-facing buds representing the characteristic crypt-villus architecture of the intestinal epithelium. Intestinal organoids can contain all the different cell types of the intestinal epithelium, e.g. enterocytes, goblet cells, Paneth cells and enteroendocrine cells. Together with the accurate representation of the tissue architecture and cell-type composition, organoids have been shown to also exhibit key functional similarities to the native tissue. Furthermore, their long-term stability in culture, derivation from healthy and diseased origin and genetic manipulation possibilities make intestinal organoids a useful though simplistic model for large spread use as a platform for functional studies and disease modelling.
Nevertheless, several limitations restrict their usefulness as an intestinal model. First and foremost, the organoids' closed cystic structure makes their inner (apical) surface inaccessible, and separate treatment of apical and basolateral sides — and thus transport studies — highly cumbersome. Moreover, this closed cystic structure implies that intestinal organoids accumulate shed dead cells in their lumen putting spatial strain on the organoids, thus impeding undisturbed organoid culture over longer periods of time without disruption by mechanical disruption and passaging. Furthermore, intestinal organoid cultures suffer from strongly variable sizes, shapes, morphologies and localisations between single organoids in their 3D culture environment.
Intestine-on-a-chip models
Although organoids usually are referred to as miniature organs, they lack vital features to mimic organ-level complexity. For this reason, biofabricated devices have been developed, which surpass organoid limitations. Especially microfluidic devices hold great potential as platforms for in vitro models of organs, as they enable perfusion mimicking the function of blood circulation in tissues. Apart from fluidic flow, other culture parameters are incorporated into intestine-on-a-chip devices, including architectural cues, mechanical stimulation, oxygen gradients and co-cultures with other cell populations and the microbiota, to more accurately display the physiological behaviour of the actual organ.
Microfluidics
Opposite to traditional static cell culture, in microfluidic devices, fluid flows can be created, which closely mimick physiological fluid flow patterns. Fluid flow introduces physiological shear stress to cell surfaces, introduces apical delivery of nutrients and growth factors and enables the establishment of chemical gradients of, e.g. growth factors, which are vital for proper organ development. Overall, microfluidic devices increase the control over the organ-specific microenvironment, which allows for more precise models.
Different technologies have been used to introduce microfluidic flows in intestine-on-a-chip devices, including peristaltic pumps, syringe pumps, pressure generators and pumpless systems driven by hydrostatic pressure and gravity. An example of a gravity-driven microfluidic intestine-on-a-chip device is the OrganoPlate platform by Mimetas, which has been used as a disease model for inflammatory bowel disease by Beaurivage et al.
Mechanical stimulation
Beginning from the early stages of embryonic development up to the post-natal life, the intestine is constantly exposed to a wide range of mechanical forces. Peristalsis, the involuntary and cyclic propulsion of intestinal contents, is an essential part of the digestive process. It facilitates food digestion, nutrient absorption and intestinal emptying on a macro scale and applies shear stress and radial pressure on the intestinal epithelium on a micro-scale. In particular, mechanical factors were shown to influence intestinal development and homeostasis, such as gut looping, villi formation, and crypt localisation. Moreover, the chronic absence of mechanical stimuli in the human intestine has been associated with intestinal morbidity.
A prominent example where both mechanical stimulations in the form of peristalsis and microfluidic flow are used in combination is the Emulate intestine-on-a-chip system. The system consists of a two-way central cell culture microchannel, which is separated by a porous, extracellular matrix-coated, PDMS membrane allowing the separate culture of two different cell populations in the upper and lower microchannel. The central chamber is enclosed by two vacuum chambers running in parallel. The application of vacuum allows the cyclic unidirectional expansion of the porous membrane separating the channels to mimic peristaltic motion
Architectural cues
As in traditional organoid culture, introducing a third culture dimension is critical for a better representation of the microanatomy of a tissue. Since 3D cell cultures implement more physiologically relevant biochemical and mechanical cues, 3D cultures generally achieve better cell viability and a more physiological transcriptome and proteome. Moreover, tissue homeostasis processes such as proliferation, differentiation and cell death are represented in a more physiological manner. The 3D support of cell cultures is commonly based on hydrogels, which mimick the native extracellular matrix. Cells can either be embedded into hydrogels or grown on a predefined micro-engineered hydrogel surface. The most commonly used hydrogel for 3D intestinal systems is Matrigel, a solubilised basement membrane extract from mouse sarcoma. However, Matrigel has significant disadvantages such as a xenogeneic origin, bath-to-batch variability, high cost and a poorly defined composition. As these factors hinder clinical translation, other hydrogels are increasingly used in 3D intestinal models, including fibrin, collagen, hyaluronic acid and PEG-based synthetic hydrogels.
In tissue engineering, microfabrication techniques are of critical importance, especially in modelling the tissue microenvironment. Apart from designing and fabricating the microfluidic device itself, microfabrication techniques are also used to create 3D microstructures which allow the patterning of cell culture surfaces closely resembling the native tissue topography, i.e. the crypt-villus-axis.
A prominent example of an intestine-on-a-chip system relying on architectural cues is the homeostatic mini-intestines by Nikolaev et al. They use microfabricated intestine-on-a-chip devices with a hydrogel chamber. The collagen-Matrigel-mix hydrogel is laser-ablated to generate a microchannel for a tubular intestinal lumen with crypt structures. The culture of intestinal stem cells in this device results in their self-organisation into a functional epithelium with the physiological spatial arrangement of the crypt-villus domains. These mini-intestines allow for an extended long term culture and give rise to rare intestinal cell types not commonly found in other 3D models. Another example for architecturally driven morphogenesis of intestine-on-a-chip models are the surface patterning techniques published by Gjorevski et al., they developed microfabricated devices to pattern hydrogel surfaces in order to reproducibly direct intestinal organoid geometry, size and cell distributions.
These examples show, that intestine-on-a-chip systems with extrinsically guided morphogenesis enable spatial and temporal control of signalling gradients and may provide a platform to extensively study intestinal morphogenesis, stem cell maintenance, crypt dynamics, and epithelial regeneration.
Co-culturing
The healthy intestine has a wide range of different functions, which requires a vast set of different cell types to fulfil them. The primary intestinal function, the absorption of nutrients, requires close contact between the intestinal epithelium and blood and lymph endothelial cells. Moreover, the intestinal microbiota plays a critical part in the digestion of food, which makes a reliable immune defence indispensable. Furthermore, muscle and nerve cells control peristalsis and satiety. Finally, mesenchymal cells are essential components of the intestinal stem cell niche as they provide physical support and secrete growth factors. Thus, incorporating different cell types in intestine-on-a-chip systems is vital to model different aspects of intestinal functions adequately.
First steps were taken in co-culturing the intestinal epithelium and the microbiota in intestine-on-a-chip systems. Examples are the establishment of an in vitro model for intestinal Shigella flexneri infection using the Emulate intestine-on-a-chip system or the recreation of a complex faeces-derived microbiota population with both aerobic and anaerobic species. Similarly, researchers have tried to recreate an immunocompetent intestinal epithelium in intestine-on-a-chip systems, by co-culturing the intestinal epithelium with peripheral blood mononuclear cells, monocytes, macrophages or neutrophils. Moreover, the epithelial-endothelial interface has been modelled in several different systems by culturing endothelial monolayers and the intestinal epithelium on opposite sides of a porous membrane.
Apart from co-culturing intestinal cells with other cell types, also the cell population of the intestinal epithelium is of high relevance. While some rather simplistic approaches use immortalised cell lines as cell source for an intestinal epithelium, there is a shift towards the use of organoid-derived intestinal stem cells, which allows the derivation of intestinal epithelia with a more physiological cell type composition.
References
External links
MIMETAS OrganoPlate Platform with video: https://www.mimetas.com/en/perfused-tubules/
EMULATE Duodenum Intestine-Chip: https://emulatebio.com/duodenum-intestine-chip/
Homeostatic mini-intestine video: https://www.youtube.com/watch?v=IHKuri9sFEM&list=PLdV2S7pxgq9ZY1IBzIRJxDlq-lNKClsnW
Microfluidics
Biotechnology
Tissue engineering | Intestine-on-a-chip | [
"Chemistry",
"Materials_science",
"Engineering",
"Biology"
] | 2,439 | [
"Biological engineering",
"Microfluidics",
"Microtechnology",
"Cloning",
"Chemical engineering",
"Biotechnology",
"Tissue engineering",
"nan",
"Medical technology"
] |
78,683,818 | https://en.wikipedia.org/wiki/HD%2076920 | HD 76920 is a solitary orange-hued star with an orbiting exoplanetary companion in the southern constellation of Volans, close to the border with Carina. With an apparent magnitude of 7.82, it is too faint to be seen by the naked eye from Earth but is readily observable through binoculars. It is located at a distance of according to Gaia EDR3 parallax measurements, and is moving away at a heliocentric radial velocity of 20.09 km/s.
Stellar properties
This is an aging giant star with a stellar classification of K1 III. At the age of billion years, it has evolved past the main sequence after depleting its hydrogen supply at the core. It is currently in the midst of ascending the red-giant branch (RGB), fast approaching the RGB bump, where deep stellar convection temporarily stalls the ascent. As expected of RGB stars, it exhibits solar-like oscillations. It has 1.22 times the mass of the Sun but has expanded to 8.68 times the Sun's radius. The star is radiating 29.5 times the luminosity of the Sun from its inflated photosphere at an effective temperature of .
Planetary system
In 2017, radial-velocity observations made using spectrographs at the Anglo-Australian Telescope, the Cerro Tololo Inter-American Observatory, and the MPG/ESO telescope revealed the existence of an exoplanet around HD 76920. The planet, HD 76920 b, is an eccentric Jupiter with a minimum mass of 3.57 and a very high orbital eccentricity of 0.8782, which at the time of discovery made it the most eccentric known planet orbiting an evolved star. Since the host star appears to be single, this was likely caused by a scattering event rather than Kozai oscillations.
Because of its high eccentricity, despite an Earth-like semi-major axis of 1.165 AU and a period of , the planet approaches the star to within 2.4 stellar radii at its perihelion. This is currently not causing any substantial orbital decay; thus the planet is expected to survive for the next 50–80 million years without falling into the star. However, after about 100 million years, stellar evolution and tidal interactions will doom it to be engulfed.
The planet has a relatively high probability (16%) to transit its host star, but such a transit has yet to be detected by TESS.
See also
Kepler-432b: another eccentric super-Jupiter orbiting a K-type giant star.
HD 20782 b: the most eccentric known exoplanet.
References
K-type giants
Volans
076920
CD-66 00659
J08551682-6715555
043803
Planetary systems with one confirmed planet | HD 76920 | [
"Astronomy"
] | 587 | [
"Volans",
"Constellations"
] |
78,684,432 | https://en.wikipedia.org/wiki/Murmansk%20train%20collision | The Murmansk train collision occurred on 18 December 2024, when a passenger train and a freight train collided in Zelenoborsky, Murmansk Oblast, Russia. Two people were killed and 31 people were injured.
Two trains were involved in a collision at Knyazhaya Station when one train ran into the side of another. Two passengers were killed and 31 others were injured. Passenger train #11 was travelling from Murmansk to Saint Petersburg with 337 passengers. Freight train #2013 was travelling from Titan, Murmansk Oblast to the south.
There was a derailment of four tail cars of the passenger train and 14 loaded cars from the tail of the freight train.
See also
List of rail accidents (2020–present)
References
2024 in Russia
Railway accidents in 2024
Train collisions in Russia
History of Murmansk Oblast
Accidents and incidents involving Russian Railways | Murmansk train collision | [
"Technology"
] | 178 | [
"Railway accidents and incidents",
"Rail accident stubs"
] |
78,684,836 | https://en.wikipedia.org/wiki/PKS%201741-03 | PKS 1741-03 is a blazar located in the constellation of Ophiuchus. This is core-dominated quasar located at a redshift of (z) 1.054, found to be highly polarized. It was first discovered in 1970 as an extragalactic radio source by astronomers and has a radio spectrum appearing to be flat, making it a flat-spectrum source.
Description
PKS 1741-03 is found to undergo a period of extreme scattering event (ESE). This is a dramatic change represented in flux density of radio sources, usually showing a decreasing trend in flux with a duration period of at least several weeks to months. During its ESE period, there was an increase in its angular diameter by 0.7 milliarcsecond. When observed on timescales of few months, PKS 1741-03 exhibited extreme variations at 2.7 GHz but no traces of violent outbursts in its light curve. Variability was also detected in the blazar at 1.49 GHz likely caused by refractive interstellar scintillation.
Radio imaging made by Very Long baseline Interferometry shows PKS 1741-03 to be a simple but compact source, consisting of two components dominated by a central radio core. There is presence of much weaker emission located south of the core which becomes noticed at high frequencies. Imaging made by Very Long Baseline Array shows PKS 1741-03 has a weak component at both epochs. Other VLBI observations at 2 and 8 GHz shows a bright component and a diffused jet structure.
Seven components have been discovered inside the parsec-scale jet of PKS 1741-03. Based on interferometric imaging, the jet components display superluminal motion of various speeds with ranges of between 3.5 and 6.1c. Further evidence also shows they are moving ballistically with the exception of one component displaying signs of bent trajectory.
In 2022, PKS 1741-03 was found to be a candidate source of a neutrino event. IceCube Observatory located at the South Pole detected a high-energy neutrino event, designated as 220205B above 200 TeV and found it to be associated with the blazar. This observation occurred while PKS 1741-03 was undergoing a powerful flare.
References
External links
PKS 1741-03 on SIMBAD
PKS 1741-03 on NASA/IPAC Database
Blazars
Quasars
Ophiuchus
Active galaxies
2829362
Astronomical objects discovered in 1970 | PKS 1741-03 | [
"Astronomy"
] | 516 | [
"Ophiuchus",
"Constellations"
] |
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