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70,956,818 | https://en.wikipedia.org/wiki/HD%20120213 | HD 120213 (HR 5188) is a solitary star in the southern circumpolar constellation Chamaeleon. It is faintly visible to the naked eye with an apparent magnitude of 5.94 and is estimated to be 910 light years away from the Solar System. However, the object is drifting closer with a heliocentric radial velocity of .
HD 120213 has a stellar classification of K2 III: CN−1 CH −2.5, indicating that its a red giant with an under abundance of CH molecules and cyano radicals in its spectrum. It has also been classified as a mild barium star, but there is uncertainty about the spectral class. It has 4.2 times the mass of the Sun and an enlarged radii of . It shines at 503 times the luminosity of the Sun from its photosphere at an effective temperature of , giving it an orange hue. HD 120213 has a metallicity 56% that of the Sun and spins with a projected rotational velocity too low to be accurately measured.
References
Chamaeleon
K-type giants
Barium stars
120213
068009
5188
Chamaeleontis, 50
PD-82 585 | HD 120213 | [
"Astronomy"
] | 250 | [
"Chamaeleon",
"Constellations"
] |
70,956,993 | https://en.wikipedia.org/wiki/HD%2072945%20and%20HD%2072946 | HD 72945 and HD 72946 form a co-moving star system in the northern constellation of Cancer. HD 72945 is a binary star that is dimly visible to the naked eye as a point of light with an apparent visual magnitude of 5.91. At an angular separation of (as of 2020) is the fainter companion star HD 72946 at magnitude 7.25. It is being orbited by a brown dwarf. The system as a whole is located at a distance of approximately 84 light years from the Sun based on parallax measurements.
The discovery of this double star was announced by F. G. W. Struve in 1782, and later given the discovery code STF 1245. Their common proper motion was confirmed by A. van Maanen in 1916, and this suggested they are physically associated. The projected separation of the two systems is . Based on astrometric measurements from the Gaia spacecraft, the semimajor axis of this system is . Assuming they are gravitationally bound, they would have an orbital period of around 2,500 years.
There is an additional candidate stellar companion at an angular separation of , which would make this a four star system. (This object has the 2MASS designation J08354678+0635294.) Three additional faint companions detected by Struve are most likely background stars.
HD 72945
The binary nature of HD 72945 was announced in 1919 by A. H. Joy and G. Abetti at the Mount Wilson Observatory. Observed variations in the radial velocity of the primary component inferred an orbiting stellar companion. This is a single-lined spectroscopic binary system with a period of 14.3 days and an orbital eccentricity of 0.33. The minimum value for the semimajor axis is only 5.9 times the radius of the Sun, although the actual value is uncertain because the orbital inclination is unknown.
The visible component of this system has a stellar classification of F8 V, matching an ordinary F-type main-sequence star. It has 1.25 times the mass of the Sun and 1.4 times the Sun's radius. The star is radiating 2.4 times the luminosity of the Sun from its photosphere at an effective temperature of 6,222 K. It has an estimated age of approximately 1.6 billion years. The derived minimum mass for the secondary component is .
HD 72946
This is a G-type main-sequence star with a class of G5V. It has about the same size and mass as the Sun. However, the star is slightly more active than the Sun, and thus probably younger. It is metal-rich, showing a higher abundance of elements other than hydrogen and helium compared to the Sun.
In 2016, a candidate brown dwarf companion in orbit around HD 72946 was announced. It was discovered based on radial velocity monitoring over a twenty-year period. The companion was confirmed in 2020. It has a classification of L5.0, a derived temperature of , and a mass near the hydrogen-burning limit. The orbit lies just outside the ice line of the host star, with a semimajor axis of about . It is orbiting with a period of 16 years and an eccentricity of 0.498.
References
F-type main-sequence stars
G-type main-sequence stars
Brown dwarfs
Spectroscopic binaries
Cancer (constellation)
3395
BD 07 1997
9271
072945
042172 | HD 72945 and HD 72946 | [
"Astronomy"
] | 722 | [
"Cancer (constellation)",
"Constellations"
] |
70,957,264 | https://en.wikipedia.org/wiki/Motorola%20Edge%2030 | Motorola Edge 30 is a series of Android smartphones developed by Motorola Mobility, a subsidiary of Lenovo, launched on 2022.
References
External links
Mobile phones introduced in 2022
Android (operating system) devices
Motorola smartphones
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording | Motorola Edge 30 | [
"Technology"
] | 59 | [
"Mobile technology stubs",
"Mobile phone stubs"
] |
70,958,960 | https://en.wikipedia.org/wiki/Atmospheric%20circulation%20of%20exoplanets | Atmospheric circulation of a planet is largely specific to the planet in question and the study of atmospheric circulation of exoplanets is a nascent field as direct observations of exoplanet atmospheres are still quite sparse. However, by considering the fundamental principles of fluid dynamics and imposing various limiting assumptions, a theoretical understanding of atmospheric motions can be developed. This theoretical framework can also be applied to planets within the Solar System and compared against direct observations of these planets, which have been studied more extensively than exoplanets, to validate the theory and understand its limitations as well.
The theoretical framework first considers the Navier–Stokes equations, the governing equations of fluid motion. Then, limiting assumptions are imposed to produce simplified models of fluid motion specific to large scale motion atmospheric dynamics. These equations can then be studied for various conditions (i.e. fast vs. slow planetary rotation rate, stably stratified vs. unstably stratified atmosphere) to see how a planet's characteristics would impact its atmospheric circulation. For example, a planet may fall into one of two regimes based on its rotation rate: geostrophic balance or cyclostrophic balance.
Atmospheric motions
Coriolis force
When considering atmospheric circulation we tend to take the planetary body as the frame of reference. In fact, this is a non-inertial frame of reference which has acceleration due to the planet's rotation about its axis. Coriolis force is the force that acts on objects moving within the planetary frame of reference, as a result of the planet's rotation. Mathematically, the acceleration due to Coriolis force can be written as:
where
is the flow velocity
is the planet's angular velocity vector
This force acts perpendicular to the flow and velocity and the planet's angular velocity vector, and comes into play when considering the atmospheric motion of a rotating planet.
Mathematical models
Navier-Stokes momentum equation
Conservation of momentum for a flow is given by the following equation:
where
is the material derivative
is the pressure
is the density
is the gravitational acceleration
is the vector from the rotation axis
is the force of friction
The term is the centripetal acceleration due to the rotation of the planet.
Simplified model for large-scale motion
The above equation can be simplified to a form suitable for large-scale atmospheric motion. First, the velocity vector is split into the three components of wind:
where
is the zonal wind
is the meridional wind
is the vertical wind
Next, we ignore friction and vertical wind. Thus, the equations for zonal and meridional wind simplify to:
and the equation in the vertical direction simplifies to the hydrostatic equilibrium equation:
where the parameter has absorbed the vertical component of the centripetal force. In the above equations:
is the Coriolis parameter, is the latitude and is the radius of the planet.
Key drivers of circulation
Thermodynamics
Temperature gradients are one of the drivers of circulation, as one effect of atmospheric flow is to transport heat from places of high temperature to those of low temperature in an effort to reach thermal equilibrium. Generally, planets have stably stratified atmospheres. This means that motion due to temperature gradient in the vertical direction is opposed by the pressure gradient in the vertical direction. In this case, it is the horizontal temperature gradients (on constant pressure surfaces) which drive circulation. Such temperature gradients are typically maintained by uneven heating/cooling throughout a planet's atmosphere. On Earth, for example, at the equator, the atmosphere absorbs more net energy from the Sun that it does at the poles.
Planetary rotation
As noted previously, planetary rotation is important when it comes to atmospheric circulation as Coriolis and centripetal forces arise as a results of planetary rotation. When considering a steady version of the simplified equations for large-scale motion presented above, both Coriolis and centripetal forces work to balance out the horizontal pressure gradients. Depending on the rotation rate of the planet, one of these forces will dominate and affect the atmospheric circulation accordingly.
Geostrophic balance
For a planet with rapid rotation, the Coriolis force is the dominant force which balances pressure gradient. In this case the equations for large-scale motion further simplify to:
where the subscript denotes a constant altitude surface and the subscript denotes geostrophic wind. Note that in this case, the geostrophic wind is perpendicular to pressure gradient. This is due to the fact that Coriolis force acts perpendicularly to the direction of wind. Therefore, since pressure gradient induces a wind parallel to the gradient, the Coriolis force will act perpendicularly to the pressure gradient. As Coriolis force dominates in this regime, the resulting winds are perpendicular to pressure gradient.
Cyclostrophic balance
For a planet with a low rotation rate and negligible Coriolis force, pressure gradient may instead be balanced by centripetal acceleration. In this case the equations for large-scale motion further simplify to:
for a prevailing wind in the east-west direction.
See also
Exometeorology
Extraterrestrial atmospheres
References
Exoplanetology
Equations of astronomy | Atmospheric circulation of exoplanets | [
"Physics",
"Astronomy"
] | 1,054 | [
"Concepts in astronomy",
"Equations of astronomy"
] |
70,959,045 | https://en.wikipedia.org/wiki/Amanda%20Paulovich | Amanda Grace Paulovich is an oncologist, and a pioneer in proteomics using multiple reaction monitoring mass spectrometry to study tailored cancer treatment.
Education
Paulovich received a BS in Biological Sciences from Carnegie Mellon University in 1988, a PhD in Genetics from University of Washington in 1996, under the direction of Leland Hartwell. She also received a MD from University of Washington in 1998. Follow her residency in Internal Medicine at Massachusetts General Hospital, she also completed a Postdoctoral Fellowship in Computational Biology at the Massachusetts Institute of Technology Whitehead Center for Genomic Research in 2003, and a Fellowship in Medical Oncology at the Dana Farber Cancer Institute in 2004.
Career
Paulovich is a Professor in Clinical Research, an Aven Foundation Endowed Chair, and the Director of Early Detection Initiative at the Fred Hutchinson Cancer Research Center. She was inducted to the American Society for Clinical Inviestigation in 2012.
Paulovich is an expert in proteomics. Her targeted proteomics method uses multiple reaction monitoring mass spectrometry to target cancer biomarkers with ongoing clinical trials, and was named Method of the Year in 2012 by Nature Methods. She founded Precision Assays in 2016, whose rights to targeted assays were acquired by CellCarta in 2022.
Awards
2014 Life Science Innovation Northwest Woman to Watch in Life Science Award
2015 Human Proteome Organization (HUPO) Distinguished Achievement in Proteomic Sciences Award
Patent applications
Identification and use of biomarkers for detection and quantification of the level of radiation exposure in a biological sample (2011) US 20130052668 A1
Compositions and methods for reliably detecting and/or measuring the amount of a modified target protein in a sample (2011) US 20130052669 A1
References
Living people
University of Washington alumni
Carnegie Mellon University alumni
American oncologists
Mass spectrometrists
University of Washington faculty
20th-century American women scientists
Year of birth missing (living people)
Fred Hutchinson Cancer Research Center people | Amanda Paulovich | [
"Physics",
"Chemistry"
] | 398 | [
"Biochemists",
"Mass spectrometry",
"Spectrum (physical sciences)",
"Mass spectrometrists"
] |
70,959,272 | https://en.wikipedia.org/wiki/HD%2080194 | HD 80194 (HR 3695) is a solitary star in the southern circumpolar constellation Chamaeleon. It has an apparent magnitude of 6.12, allowing it to be faintly seen with the naked eye. Parallax measurements place the object at a distance of 351 light years and is currently receding with a poorly constrained radial velocity of .
HD 80194 has a stellar classification of K1 III, indicating that it is a red giant that has exhausted its core hydrogen. It is thought to be a red clump star, on the cool end of the horizontal branch and fusing helium in its core. It has 115% the mass of the Sun but has expanded to 9.82 times its girth. It shines at 47 times the luminosity of the Sun from its photosphere at an effective temperature of , giving it an orange glow. HD 80194 has an iron abundance 81% that of the Sun and spins slowly with a projected rotational velocity lower than .
References
Chamaeleon
K-type giants
080194
045166
3695
CD-76 416
Chamaeleontis, 12 | HD 80194 | [
"Astronomy"
] | 238 | [
"Chamaeleon",
"Constellations"
] |
70,959,639 | https://en.wikipedia.org/wiki/Midpoint%20theorem%20%28conics%29 | In geometry, the midpoint theorem describes a property of parallel chords in a conic. It states that the midpoints of parallel chords in a conic are located on a common line.
The common line or line segment for the midpoints is called the diameter. For a circle, ellipse or hyperbola the diameter goes through its center. For a parabola the diameter is always perpendicular to its directrix and for a pair of intersecting lines (from a degenerate conic) the diameter goes through the point of intersection.
Gallery ( = eccentricity):
References
David Alexander Brannan, Matthew F. Esplen, Jeremy J. Gray (1999) Geometry Cambridge University Press , pages 59–66
Aleksander Simonic (November 2012) "On a Problem Concerning Two Conics", Crux Mathematicorum, volume 38(9): 372–377
C. G. Gibson (2003) Elementary Euclidean Geometry: An Introduction. Cambridge University Press pages 65–68
External links
Locus of Midpoints of Parallel Chords of Central Conic passes through Center at the Proof Wiki
midpoints of parallel chords in conics lie on a common line - interactive illustration
Conic sections
Theorems in plane geometry | Midpoint theorem (conics) | [
"Mathematics"
] | 250 | [
"Theorems in plane geometry",
"Theorems in geometry"
] |
70,959,988 | https://en.wikipedia.org/wiki/Nova%20Herculis%202021 | Nova Herculis 2021, also known V1674 Herculis, was a nova in the constellation Hercules. It reached a peak brightness of magnitude 6.0, making it visible to the naked eye under ideal observing conditions. It was discovered on June 12, 2021, by Seiji Ueda of Kushiro Japan, just hours before it obtained peak brightness. The discovery images were taken with a Canon EOS 6D digital camera with a 200 mm lens, when the nova was at magnitude 8.4. Subsequent analysis of ASAS-SN data showed the star had a magnitude of 16.62 (g band) 8.4 hours before it was discovered. Of the galactic novae for which detailed light curves are available, Nova Herculis 2021 had the fastest decline from peak brightness ever seen. This nova has been detected throughout the electromagnetic spectrum, from radio to gamma rays.
All novae are binary stars, consisting of a white dwarf orbited by a mass-losing "donor star". Photometric observations taken during June, July and August 2021 found that binary pair's orbital period is 3.670416 ± 0.0008 hours. The Zwicky Transient Facility had been observing the region of the sky containing Nova Herculis 2021 since March 2018, and analysis of that data yielded a spin period of 8.357 minutes for the white dwarf.
References
External links
Novae
Hercules (constellation)
2021 in science
Herculis, V1674
20210612 | Nova Herculis 2021 | [
"Astronomy"
] | 306 | [
"Novae",
"Astronomical events",
"Hercules (constellation)",
"Constellations"
] |
70,960,096 | https://en.wikipedia.org/wiki/Judith%20A.%20Todd | Judith A. Todd is a British-American materials scientist whose research topics have included multilayered coatings, the properties of metal alloys and ceramics, the use of lasers in the nondestructive analysis of materials, and the history of ancient metallurgy. She is the P. B. Breneman Chair at Pennsylvania State University, where she heads the Department of Engineering Science and Mechanics.
Education and career
Todd is originally from Wakefield in West Yorkshire. She studied materials science at the University of Cambridge, earning a bachelor's degree in 1972, and completing her Ph.D. in 1977; her dissertation topic concerned archaeometry, and in particular the applications of materials science to archaeology. Her field work for her dissertation took her to work with the Deemay people of Ethiopia, studying ancient ironworking techniques.
After postdoctoral research at Imperial College and Stony Brook University, she became a researcher on a project in the development of new steel alloys at the University of California, Berkeley, funded by the Department of Energy. From there she moved to faculty positions at the University of Southern California, and, in 1990, the Illinois Institute of Technology, where she was named the Iron and Steel Society Professor in 1995 and, later, associate dean for research. In 2000 she moved to her present position at Pennsylvania State University.
Service and recognition
Todd was the 2009 president of the Society of Engineering Science, the vice-president for manufacturing of the American Society of Mechanical Engineers from 2002 to 2005, and the president of ASM International from 2021 to 2022.
She was named a Fellow of the American Society of Mechanical Engineers in 2001, and is also a Fellow of ASM International and of the Association for Women in Science. In 2006 she won the Presidential Award for Excellence in Science, Mathematics, and Engineering Mentoring.
References
External links
Year of birth missing (living people)
Living people
Archaeometallurgists
British metallurgists
British women engineers
American metallurgists
American women engineers
Alumni of the University of Cambridge
University of Southern California faculty
Illinois Institute of Technology faculty
Pennsylvania State University faculty
Fellows of the American Society of Mechanical Engineers | Judith A. Todd | [
"Chemistry"
] | 427 | [
"Archaeometallurgy",
"Archaeometallurgists"
] |
70,960,966 | https://en.wikipedia.org/wiki/Barak%20Kol%20%28physicist%29 | Barak Kol (born August 1968) is an Israeli theoretical physicist who studies fundamental laws, high-energy physics, and general relativity. He holds the Michael Polak chair in theoretical physics at the Racah Institute of Physics at the Hebrew University of Jerusalem.
Biography
Kol completed his BSc in physics and mathematics at Tel Aviv University in 1989, following which he did his military service in the IDF. Afterwards, he completed his PhD at Stanford University in 1998 under the guidance of Leonard Susskind, during which he coined the term "(p,q) webs." His most widely cited paper is on the subject and has over 500 citations.
Following the completion of his PhD, Kol was a postdoctoral fellow at Tel Aviv University (1998-2000) and at the Institute for Advanced Study (2000-2002). During the latter, he was hosted by Nathan Seiberg. Afterwards, he became a faculty member at the Racah Institute of Physics.
Kol's previous research topics include phase transitions in black strings, effective field theories in general relativity, black holes in string theory, and the three-body problem.
He was previously Head of the Physics Studies at the Racah Institute.
References
Israeli physicists
Theoretical physicists
1968 births
Living people
Stanford University alumni
Tel Aviv University alumni
Academic staff of the Hebrew University of Jerusalem
Jewish physicists
Relativity theorists | Barak Kol (physicist) | [
"Physics"
] | 277 | [
"Theoretical physics",
"Theoretical physicists",
"Relativity theorists",
"Theory of relativity"
] |
70,961,697 | https://en.wikipedia.org/wiki/Power-voltage%20curve | Power-voltage curve (also P-V curve) describes the relationship between the active power delivered to the electrical load and the voltage at the load terminals in an electric power system under a constant power factor. When plotted with power as a horizontal axis, the curve resembles a human nose, thus it is sometimes called a nose curve. The overall shape of the curve (similar to a parabola placed on its side) is defined by the basic electrical equations and does not change much when the characteristics of the system vary: leading power factor lead stretches the "nose" further to the right and upwards, while the lagging one shrinks the curve. The curve is important for voltage stability analysis, as the coordinate of the tip of the nose defines the maximum power that can be delivered by the system.
As the load increases from zero, the power-voltage point travels from the top left part of the curve to the tip of the "nose" (power increases, but the voltage drops). The tip corresponds to the maximum power that can be delivered to the load (as long as sufficient reactive power reserves are available). Past this "collapse" point additional loads cause drop in both voltage and power, as the power-voltage point travels to the bottom left corner of the plot. Intuitively this result can be explained when a load that consists entirely of resistors is considered: as the load increases (its resistance thus lowers), more and more of the generator power dissipates inside the generator itself (that has it own fixed resistance connected sequentially with the load). Operation on the bottom part of the curve (where the same power is delivered with lower voltage – and thus higher current and losses) is not practical, as it corresponds to the "uncontrollability" region.
If sufficient reactive power is not available, the limit of the load power will be reached prior to the power-voltage point getting to the tip of the "nose". The operator shall maintain a sufficient margin between the operating point on the P-V curve and this maximum loading condition, otherwise, a voltage collapse can occur.
A similar curve for the reactive power is called Q-V curve.
References
Sources
Electrical engineering | Power-voltage curve | [
"Engineering"
] | 445 | [
"Electrical engineering"
] |
70,963,077 | https://en.wikipedia.org/wiki/Hilkka%20I.%20Kentt%C3%A4maa | Hilkka Inkeri Kenttämaa is a researcher in organic and bioorganic mass spectrometry, and the Frank Brown Endowed Distinguished Professor of Chemistry at Purdue University. She is a pioneer in distonic radical cation research and laser-induced acoustic desorption.
Early life and education
Kenttämaa had initially planned to study mathematics, instead of chemistry, despite both her parents being chemists. She studied at Helsinki University, earning a BS in 1977, a MS in 1978, a Phil. Lic.in 1981, and a PhD in Organic Chemistry in 1986. She did post-doctoral research with R. Graham Cooks at Purdue University in 1986.
Career
She began her career as a research scientist at Helsinki University, the Academy of Finland, and as a visiting research scientist at Purdue University. She joined the faculty at Purdue University in 1989, and was promoted to Full Professor in 1999. Her projects include using tandem mass spectrometry to study reaction mechanisms and fast pyrolysis process. She is a pioneer in distonic radical cation research and laser-induced acoustic desorption.
She was elected as a member of the Finish Academy of Science in 2004. She serves as a subject editor in basic mass spectrometry for Mass Spectrometry Reviews.
Honors and awards
1991 American Society for Mass Spectrometry Young Investigator Research Award
1996 National Science Foundation Career Advancement Award in the Organic Dynamics Program of the Chemistry Division
2009 Purdue University Provost's Award for Outstanding Graduate Faculty Mentor
2013 Purdue University Leadership Award of the College of Science
2015 American Chemical Society the Frank H. Field and Joe L. Franklin Award for Outstanding Achievement in Mass Spectrometry
2015 Purdue University Foundation Innovators Hall of Fame
2016 Fellow of the American Association for the Advancement of Science
2016 the Analytical Scientist The Power List 2016 the Top 50 Most Influential Women in the Analytical Sciences
2020 NASA Engineering and Safety Center Group Achievement Award, as part of the Transient Combustion Modeling for Hypergolic Engines Assessment Team
Selected publications
Below is a list of articles co-authored by Kenttämaa, with over 100 citations:
Vicki H. Wysocki; Hilkka I. Kenttämaa; R. Graham Cooks (1987) "Internal energy distributions of isolated ions after activation by various methods". International Journal of Mass Spectrometry and Ion Processes 75 (2): 181–208.
Krista M. Stirk; L. K. Marjatta Kiminkinen; Hilkka I. Kenttamaa (1992) "Ion-molecule reactions of distonic radical cations". Chemical Reviews 92 (7):1649–1665.
David S. Pinkston; Penggao Duan; Vanessa A. Gallardo; Steven C. Habicht; Xiaoli Tan; Kuangnan Qian; Murray Gray; Klaus Müllen; Hilkka I. Kenttämaa (2009) "Analysis of asphaltenes and asphaltene model compounds by laser-induced acoustic desorption/Fourier transform ion cyclotron resonance mass spectrometry". Energy Fuels 23 (11): 5564–5570.
David Borton, II; David S. Pinkston; Matthew R. Hurt; Xiaoli Tan; Khalid Azyat; Alexander Scherer; Rik Tykwinski; Murray Gray; Kuangnan Qian; Hilkka I. Kenttämaa (2010) "Molecular structures of asphaltenes based on the dissociation reactions of their ions in mass spectrometry". Energy Fuels 24 (10): 5548–5559.
Trenton H. Parsell; Benjamin C. Owen; Ian Klein; Tiffany M. Jarrell; Christopher L. Marcum; Laura J. Haupert; Lucas M. Amundson; Hilkka I. Kenttämaa; Fabio Ribeiro; Jeffrey T. Miller; Mahdi M. Abu-Omar (2013) "Cleavage and hydrodeoxygenation (HDO) of C–O bonds relevant to lignin conversion using Pd/Zn synergistic catalysis". Chemical Science 4 (2): 806–813.
Trenton Parsell; Sara Yohe; John Degenstein; Tiffany Jarrell; Ian Klein; Emre Gencer; Barron Hewetson; Matt Hurt; Jeong Im Kim; Harshavardhan Choudhari; Basudeb Saha; Richard Meilan; Nathan Mosier; Fabio Ribeiro; W. Nicholas Delgass; Clint Chapple; Hilkka I. Kenttämaa; Rakesh Agrawal; Mahdi M. Abu-Omar (2015) "A synergistic biorefinery based on catalytic conversion of lignin prior to cellulose starting from lignocellulosic biomass". Green Chemistry 17 (3): 1492–1499.
Hao Luo; Ian M. Klein; Yuan Jiang; Hanyu Zhu; Baoyuan Liu; Hilkka I. Kenttämaa; Mahdi M. Abu-Omar (2016) "Total utilization of miscanthus biomass, lignin and carbohydrates, using earth abundant nickel catalyst". ACS Sustainable Chemistry & Engineering 4 (4): 2316–2322.
Book chapter
Kawthar Z. Alzarieni; Hilkka I. Kenttämaa. "The distillation precipitation fractionation mass spectrometry (DPF-MS) method for molecular profiling of crude oil" in The Chemistry of Oil and Petroleum Products. Merv Fingas (Ed.). De Gruyter 2022.
Patent applications
High power laser induced acoustic desorption probe (2007) US 7619217 B2
Laser-induced acoustic desorption/atmospheric pressure chemical ionization of compounds(2011) US 8344319 B2
Sample deposition chamber for laser-induced acoustic desorption (liad) foils (2012) WO 2013103417 A3
Differentially pumped dual linear quadrupole ion trap mass spectrometer (2015) US 9496127 B2
Multichannel Pulsed Valve Inlet System (2019) US
References
Mass spectrometrists
Purdue University faculty
University of Helsinki alumni
Fellows of the American Association for the Advancement of Science
Living people
Year of birth missing (living people)
Finnish biochemists | Hilkka I. Kenttämaa | [
"Physics",
"Chemistry"
] | 1,301 | [
"Biochemists",
"Mass spectrometry",
"Spectrum (physical sciences)",
"Mass spectrometrists"
] |
70,963,880 | https://en.wikipedia.org/wiki/HD%2046568 | HD 46568 (HR 2399) is a solitary star in the southern constellation Columba. It is faintly visible to the naked eye with an apparent magnitude of 5.25. Parallax measurements place the object at a distance of 284 light years and is currently receding with a heliocentric radial velocity of .
HD 46568 has a stellar classification of G8 III, indicating that it is a yellow giant. At present it has nearly twice the mass of the Sun but at an age of 1.68 billion years it has expanded to 10.66 times the radius of the Sun. It has an effective temperature of , giving it a yellow glow. However, the star's large radius yields a luminosity 60 times that of Sun. HD 46568's metallicity is 69% that of the Sun and it spins with a poorly constrained projected rotational velocity of .
References
Columba (constellation)
G-type giants
046568
031165
2399
CD-37 2889
Columbae, 104 | HD 46568 | [
"Astronomy"
] | 213 | [
"Columba (constellation)",
"Constellations"
] |
70,965,779 | https://en.wikipedia.org/wiki/Ardblair%20Stones | The Ardblair Stones is a strength feat, where nine reinforced concrete lifting stones of ascending weight are used. The 9 stones weigh , , , , , , , and respectively. The goal of the competition is to lift each stone sequentially from smallest to largest and place them on top of 4 ft 4 in (52 in) whiskey barrels as quickly as possible. The stones are named for Ardblair Castle located in Blairgowrie, Perthshire in Scotland, close to where they originated.
The stones were created by Charlie Blair Oliphant in 2008, based on World's Strongest Man competitions he had seen on TV as a child. Oliphant wanted to create an event that was accessible to all people, regardless of age and ability, and would be free to all. The stones made their debut in September 2012 at the Highland Games. Based on the success and interest of the event, the stones have since toured the United Kingdom.
World records
Men - 9 out of 9 stones in 21.81 seconds by Tom Stoltman in 2019
Women - 7 out of 9 stones in 37.14 seconds by Donna Moore in 2019
References
External links
Official site
Stones
Strongmen competitions
Scottish games | Ardblair Stones | [
"Physics"
] | 245 | [
"Stones",
"Physical objects",
"Matter"
] |
70,966,557 | https://en.wikipedia.org/wiki/Radium%20silk | Radium silk was a commonly used name for a type of lightweight, lustrous silk primarily used in women's clothing and undergarments from the middle of the first decade of the 1900s until the term went out of vogue in the 1920s. Although the name references radium, a radioactive element first discovered in 1898, the substance is not contained in the fabric. As the deleterious effects of radium on the human body became better known in the middle-1920s, the use of the word as an adjective gained a negative connotation and fell out of favor among advertisers and consumers alike.
History
Origin
The descriptive term "radium silk" began to be used no later than 1903. The term apparently originated in the fashion markets of Paris in association with particularly lustrous fabrics, with reference made to the newly discovered element radium, first identified in 1898. The material was notable both for its gloss and strength.
"Radium silk" did not contain radium or any other radioactive material. Rather, it was named for its tendency to shimmer in light, bringing to mind the phosphorescence of the world's newly discovered heavy metal.
The term was successfully trademarked in the United States by the Gilbert Company of New York City, which registered the mark in August 1905. Despite this proprietary claim, the phrase "radium silk" was generally used in a generic context throughout the United States. The word "radium" had a very positive connotation in this period and was used as a vapid qualifying adjective, similar to the way that the words "platinum" and "titanium" are bandied about for products not containing either metal today.
By the fall of 1906, "radium silk" had truly arrived in the fashion world of the United States. A September 1906 syndicated plate, appearing in dozens of newspapers around the country, enthusiastically described the "exquisitely toned material which has had such vogue in Paris for the last few months."
The article continued:
Surely there are few fabrics which can better stand popular favor. There is a delicacy, luster, and wonderful color to the radium silks that makes them peculiarly satisfying to a refined taste.
Akin to the best foulards and liberty gauzes is it, with the best qualities of both. Heavier and finer weaves than the latter, it has all its graceful clinginess, with greater durability, while the softness and simple patterns of the former are enhanced by a high sheen, caused by being woven of organzine so fine that the single thread is barely visible.
But the chief beauty of the radium silks is their opalescent coloring, so indescribably lovely. A pink will have the soft blush of the heart of a shell; the tint of the sky shining through a fleeting cloud on a sunny day is seen in the blues, while the lavenders, greens, yellows, and even the darker colors all have the soft undertones that gives them a beautiful iridescent effect.
Downfall
Although many consumer products of this era were made containing radium, which was initially believed to have highly salutary properties, bright and shiny radium silk did not.
The turning point for "radium silk" came in 1925, when the New York Times broke the news of five deaths of watch face-painters from radiation poisoning, developed by handling radium on the job. Descriptions of the new ailment, referred to as radium necrosis, were grisly, and the disintegrating jaws and cancers developed by these Radium Girls attracted national attention. By the end of the decade the term "radium" was no longer viable as a positive descriptor, and it was hastily abandoned.
See also
Radium Girls
Footnotes
Further reading
Taylor Orci, "How We Realized Putting Radium in Everything Was Not the Answer," The Atlantic, March 7, 2013.
Animal glandular products
Biomaterials
Insect products
Woven fabrics | Radium silk | [
"Physics",
"Biology"
] | 809 | [
"Biomaterials",
"Materials",
"Matter",
"Medical technology"
] |
70,966,696 | https://en.wikipedia.org/wiki/Andrimid | Andrimid is an antibiotic natural product that is produced by the marine bacterium Vibrio coralliilyticus. Andrimid is an inhibitor of fatty acid biosynthesis by blocking the carboxyl transfer reaction of acetyl-CoA carboxylase (ACC).
Andrimid contains a pseudopeptide backbone and is synthesized through the polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) pathways. Amino acids are added by the NRPS pathway which loads amino acid monomer units into the growing chain during the molecular assembly line.
Biosynthesis
Abbreviations: ketosynthase (KS), chain length factor (CLF), dehydrogenase (DH), ketoreductase (KR), thiolation (T), transglutaminase (TG), adenylation (A), condensation (C), thioesterase (TE).
Andrimid is derived from three amino acids which are phenylalanine, valine, and glycine. Phenylalanine is converted to its other conformation, while valine and glycine residues have been elongated by two carbons derived by malonyl units. To incorporate the phenylalanine moiety into the biosynthesize of Andrimid, L-Phe must first be converted to (S)-β-Phe by the aminomutase AdmH. (S)-β-Phe reacts with ATP to active (S)-β-Phe-AMP by the A domain AdmJ which incorporates (S)-β-Phe onto the holo-AdmI(HS-AdmI), forming (S)-β-Phe-S-AdmI. AdmF catalyzes the formation of the octratrienoyl chain and the amine group of alpha-phenylalanine by acylation of its active site cysteine forming the Octratrienoyl-β-Phe-S-AdmI. The hybrid biosynthesis goes through six T domains before final tailoring to form the natural product Andrimid. Additional characteristics of the Andrimid assembly line are the beginning enzymes such as AdmH containing the aminomutase, AdmJ containing the β-Phe adenylation (A) domain which serves as the gatekeepers of the biosynthesis for determining which aromatic amino acid is used by the transglutaminase homologue AdmF. AdmF uses acyl S-T domain and β-aminoacyl-S-T domain to form the amine bond. Furthermore, the three amino acid used in Andrimid are incorporated into the assembly line by AdmH and AdmJ. (S)-β-Phe is generated by AdmH and incorporated by AdmJ. As for the other two amino acids which are valine and glycine, they must first undergo an addition of two carbons by the PKS modules AdmO and AdmM. A total of five proteins are used for andrimid biosynthesis to create the chain initiation step which are AdmA, AdnI, AdnJ, AdmF, and AdmH. During the PKS II pathway, malonyl-CoA is loaded onto the acyl carrier protein (ACP) which is transferred to the active site of ketosynthase (KS), releasing acetyl CoA to generate malonyl-CoA. This reaction undergoes chain elongation using malonyl-coenzyme A (CoA) following ketoreductase (CLF, DH, and KR). Note, the PKS II pathway is a systematic scheme, since there are not sufficient studies that demonstrate a clear route of the enzymes used for this chain elongation step of the fatty acid biosynthesis.
References
Succinimides
Dipeptides
Alkaloids
Bacterial alkaloids | Andrimid | [
"Chemistry"
] | 844 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
76,906,020 | https://en.wikipedia.org/wiki/Discharge%20regime | Discharge regime, flow regime, or hydrological regime (commonly termed river regime, but that term is also used for other measurements) is the long-term pattern of annual changes to a stream's discharge at a particular point. Hence, it shows how the discharge of a stream at that point is expected to change over the year. It is thus the hydrological equivalent of climate. The main factor affecting the regime is climate, along with relief, bedrock, soil and vegetation, as well as human activity.
Like general trends can be grouped together into certain named groups, either by what causes them and the part of the year they happen (most classifications) or by the climate in which they most commonly appear (Beckinsale classification). There are many different classifications; however, most of them are localized to a specific area and cannot be used to classify all the rivers of the world.
When interpreting such records of discharge, it is important to factor in the timescale over which the average monthly values were calculated. It is particularly difficult to establish a typical annual discharge regime for rivers with high interannual variability in monthly discharge and/or significant changes in the catchment's characteristics (e.g. tectonic influences or the introduction of water management practices).
Overview
Maurice Pardé was the first to classify river regimes more thoroughly. His classification was based on what the primary reasons for such pattern are, and how many of them there are. According to this, he termed three basic types:
Simple regimes, where there is only one dominant factor.
Mixed or double regimes, where there are two dominant factors.
Complex regimes, where there are multiple dominant factors.
Pardé split the simple regimes further into temperature-dependent (glacial, mountains snow melt, plains snow melt; latter two often called "nival") and rainfall-dependent or pluvial (equatorial, intertropical, temperate oceanic, mediterranean) categories.
Beckinsale later more clearly defined the distinct simple regimes based on climate present in the catchment area and thus splitting the world into "hydrological regions". His main inspiration was the Köppen climate classification, and he also devised strings of letters to define them. However, the system was criticised as it based the regimes on climate instead of purely on discharge pattern and also lacked some patterns.
Another attempt to provide classification of world regimes was made in 1988 by Heines et al., which was based purely on the discharge pattern and classified all patterns into one of 15 categories; however, the determination is sometimes contradictory and quite complex, and the distinction does not differentiate between simple, mixed or complex regimes as it determines the regime solely on the main peak, which is contradictory to commonly used system in the Alpine region. Hence, rivers with nivo-pluvial regimes are commonly split into two different categories, while most pluvio-nival regimes are all grouped into a single category along with complex regimes – the uniform regime, despite showing quite pronounced and regular yearly pattern. Moreover, it does not differentiate between temperature-dependant and rainfall-dependant regimes. Nonetheless, it added one new regime that was not present in Beckinsale's classification, the moderate mid-autumn regime with a peak in November (Northern Hemisphere) or May (Southern Hemisphere). This system too, is very rarely used.
In later years, most of the research was only done in the region around the Alps, so that area is much more thoroughly researched than others, and most names for subclasses of regimes are for those found there. These were mostly further differentiated from Pardé's distinction. The most common names given, although they might be defined differently in different publications, are:
Glacial, for regimes where most of water is due to melting of snow and ice and the peak occurs in late summer.
Nival, with a peak in late spring or early summer and still high importance of snow-melt.
Pluvial, which is (almost) purely based on seasonal rainfall and not on snow. A peak is usually in winter, although it can occur at any point along the year. If it occurs in the time of monsoons, it is sometimes called tropical pluvial.
Nivo-pluvial, with a nival peak in late spring and a pluvial peak in the fall. The main minimum is in winter.
Pluvio-nival, which is similar to nivo-pluvial, but the nival peak is earlier (March/April on the Northern Hemisphere) and the main minimum is in summer, not in winter.
Nivo-glacial, for regimes sharing characteristics of glacial and nival regimes and a peak in mid summer.
The Pardé's differentiation of single regimes from mixed regimes is sometimes rather considered to be based on the number of peaks rather than the number of factors as it is more objective. Most of nival and even glacial regimes have some influence of rainfall and regimes considered pluvial have some influence of snowfall in regions with continental climate; see the coefficient of nivosity. The distinction between both classifications can be seen with the nivo-glacial regime, which is sometimes considered as a mixed regime, but is often considered as a simple regime in more detailed studies. However, many groupings of multiple pluvial or nival peaks are still considered a simple regime in some sources.
Measurement of river regimes
River regimes, similarly to the climate, are compounded by averaging the discharge data for several years; ideally that should be 30 years or more, as with the climate. However, the data is much scarcer, and sometimes data for as low as eight years are used. If the flow is regular and shows very similar year-to-year pattern, that could be enough, but for rivers with irregular patterns or for those that are most of the time dry, that period has to be much longer for accurate results. This is especially the problem with wadis as they often have both traits. The discharge pattern is specific not only to a river, but also a point along a river as it can change with new tributaries and an increase in the catchment area.
This data is then averaged for each month separately. Sometimes, the average maximum and minimum for each month is also added. But unlike climate, rivers can drastically range in discharge, from small creeks with mean discharges less than 0.1 cubic meters per second to the Amazon River, which has average monthly discharge of more than 200,000 cubic meters per second at its peak in May. For regimes, the exact discharge of a river in one month is not as important as is the relation to other monthly discharges measured at the same point along a particular river. And although discharge is still often used for showing seasonal variation, two other forms are more commonly used, the percentage of yearly flow and the Pardé coefficient.
Percentage of yearly flow represents how much of the total yearly discharge the month contributes and is calculated by the following formula:
,
where is the mean discharge of a particular month and is the mean yearly discharge. Discharge of an average month is and the total of all months should add to 100% (or rather, roughly, due to rounding).
Even more common is the Pardé coefficient, discharge coefficient or simply the coefficient, which is more intuitive as an average month would have a value of 1. Anything above that means there is bigger discharge than average and anything lower means that there is lower discharge than the average. It is calculated by the following equation:
,
where is the mean discharge of a particular month and is the mean yearly discharge. Pardé coefficients for all months should add to 12 and are without a unit.
The data is often presented is a special diagram, called a hydrograph, or, more specifically, an annual hydrograph as it shows monthly discharge variation in a year, but no rainfall pattern. The units used in a hydrograph can be either discharge, monthly percentage or Pardé coefficients. The shape of the graph is the same in any case, only the scale needs to be adjusted. From the hydrograph, maxima and minima are easy to spot and the regime can be determined more easily. Hence, they are a vital part for river regimes, just as climographs are for climate.
Yearly coefficient
Similarly to Pardé's coefficient, there are also other coefficients that can be used to analyze the regime of a river. One possibility is to look how many times the discharge during the peak is larger than the discharge during the minimum, rather than the mean as with Pardé's coefficient. It is sometimes called the yearly coefficient and is defined as:
,
where is the mean discharge of the month with the highest discharge and is the mean discharge of the month with the lowest discharge. If is 0, then the coefficient is undefined.
Annual variability
Annual variability shows how much the peaks on average deviate from the perfectly uniform regime. It is calculated as the standard deviation of the mean discharge of months from the mean yearly discharge. That value is then divided by the mean yearly discharge and multiplied by 100%, i.e.:
The most uniform regimes have a value below 10%, while it can reach more than 150% for rivers with the most drastic peaks.
Grimm coefficients
Grimm coefficients, used in Austria, are not defined for a single month, but for 'doppelmonats', i.e., for two consecutive months. The mean flow of both months – January and February, February and March, March and April, and so on – is added, still conserving 12 different values throughout the year. This is done since for nival regimes, this better correlates to different types of peak (nival, nivo-glacial, glacial etc.). They are defined as follows:
(Initial definition)
(Adapted definition so values are closer to Pardé's; version used on Wikipedia)
,
where .
Coefficient of nivosity
Pardé and Beckinsale determined whether the peak is pluvio-nival, nivo-pluvial, nival or glacial based on the fact what percentage of the discharge during the warm season is contributed by the melt-water, and not by the time of the peak as it is common today. However, it has been calculated for few rivers. The values are the following:
0–6%: pluvial
6–14%: pluvio-nival
15–25%: nivo-pluvial
26–38%: transition to nival
39–50%: pure nival to nivo-glacial
more than 50%: glacial
Factors affecting river regimes
There are multiple factors that determine when a river will have a greater discharge and when a smaller one. The most obvious factor is precipitation, since most rivers get their water supply in that way. However, temperature also plays a significant role, as well as the characteristics of its catchment area, such as altitude, vegetation, bedrock, soil and lake storage. An important factor is also the human factor as humans may either fully control the water supply by building dams and barriers, or partially by diverting water for irrigation, industrial and personal use. The factor that differentiates classification of river regimes from climate the most is that rivers can change their regime along its path due to a change of conditions and new tributaries.
Climate
The primary factor affecting river regimes is the climate of its catchment area, both by the amount of rainfall and by the temperature fluctuations throughout the year. This has led Beckinsale to classify regimes based primarily on the climate. Although there is correlation, climate is still not fully reflected in a river regime. Moreover, a catchment area can span through more than one climate and lead to more complex interactions between the climate and the regime.
A discharge pattern can closely resemble the rainfall pattern since rainfall in a river's catchment area contributes to its water flow, rise of the underground water and filling of lakes. There is some delay between the peak rainfall and peak discharge, which is also dependent on the type of soil and bedrock, since the water from rain must reach the gauging station for the discharge to be recorded. The time is naturally longer for bigger catchment areas.
If the water from precipitation is frozen, such as snow or hail, it has to melt first, leading to longer delays and shallower peaks. The delay becomes heavily influenced by the temperature since temperatures below zero cause the snow to stay frozen until it becomes warmer in the spring, when temperatures rise and melt the snow, leading to a peak, which might be again a bit delayed. The time of the peak is determined by when the midday temperature sufficiently soars above , which is usually considered to be when the average temperature reaches above . In the mildest continental climates, bordering the oceanic climate, the peak is usually in March on the Northern Hemisphere or September on the Southern Hemisphere, but can be as late as August/February on the highest mountains and ice caps, where the flow also heavily varies throughout the day.
Melting of glaciers alone can also supply large amounts of water even in areas where there is little to no precipitation, as in ice cap climate and cold dry and semi-dry climates.
On the other side, high temperatures and sunny weather lead to a significant increase in evapotranspiration, either directly from river, or from moist soil and plants, leading to the fact that less precipitation reaches the river and that plants consume more water, respectively. For terrain in darker colors, the rate of evaporation is higher than for a terrain in lighter colors due to lower albedo.
Relief
Relief often determines how sharp and how wide the nival peaks are, leading Pardé to already classify mountain nival and plain nival regimes separately. If the relief is rather flat, the snow will melt everywhere in a short period of time due to similar conditions, leading to a sharp peak about three months wide. However, if the terrain is hilly or mountainous, snow located in lowlands will melt first, with the temperature gradually decreasing with altitude (about per 1000 m). Hence the peak is wider, and especially the decrease after the peak can extend all the way to late summer when the temperatures are highest. Due to this phenomenon, the precipitation in lowland areas might be rainfall, but snow in higher areas, leading to a peak quickly after the rainfall and another when the temperatures start to melt the snow.
Another important aspect is altitude. At exceptionally high altitudes, atmosphere is thinner so the solar insolation is much greater, which is why Beckinsale differentiates between mountain nival and glacial from similar regimes found at higher latitudes.
Additionally, steeper slopes lead to faster surface runoff, leading to more prominent peaks, while flat terrain allows for lakes to spread, which regulate the discharge of the river downstream. Larger catchment areas also lead to shallower peaks.
Vegetation
Vegetation in general decreases surface runoff and consequently discharge of a river, and leads to greater infiltration. Forests dominated by trees that shed their leaves during winter have an annual pattern of the extent of water interception, which shapes the pattern in its own way. The impact of vegetation is noticeable in all areas but the driest and coldest, where vegetation is scarce. Vegetation growing in the river beds can drastically hinder the flow of water, especially in the summer, leading to smaller discharges.
Soil and bedrock
The most important aspect of the ground in this regard is the permeability and water-holding capacity of the rocks and soils in the discharge basin. In general, the more the ground is permeable, the less pronounced the maxima and minima are since the rocks accumulate water during the wet season and release it during the dry season; lag time is also longer since there is less surface runoff. If the wet season is really pronounced, the rocks become saturated and fail to infiltrate excess water, so all rainfall is quickly released into the stream. On the other side, however, if the rocks are too permeable, as in the karst terrain, rivers might have a notable discharge only when the rocks are saturated or the groundwater level rises and would otherwise be dry with all the water accumulating in subterranean rivers or disappearing in ponors. Examples of rocks with high water-holding capacity include limestone, sandstone and basalt, while materials used in urban areas (such as asphalt and concrete) have very low permeability leading to flash floods.
Human activity
Human factors can also greatly change discharge of a river. On one side, water can be extracted either directly from a river or indirectly from groundwater for the purposes of drinking and irrigation, among others, lowering the discharge. For the latter, the consumption usually spikes during the dry season or during crop growth (i.e., summer and spring). On the other side, waste waters are released into streams, increasing the discharge; however, they are more or less constant all year round so they do not impact the regime as much.
Another important factor is the construction of dams, where a lot of water accumulates in a lake, making the minima and maxima less pronounced. In addition, the discharge of water is often in large part regulated in regard to other human needs, such as electricity production, meaning that the discharge of a river downstream of a dam can be completely different than upstream.
Here, an example is given for the Aswan dam. As can be observed, the yearly coefficient is lower at the dam than upstream, showing the effect of the dam.
Simple regimes
Simple regimes are hence only those that have exactly one peak; this does not hold for cases where both peaks are nival or both are pluvial, which are often grouped together into simple regimes. They are grouped into five categories: pluvial, tropical pluvial, nival, nivo-glacial and glacial.
Pluvial regime
Pluvial regimes occur mainly in oceanic and mediterranean climates, such as the UK, New Zealand, southeastern USA, South Africa and the Mediterranean regions. Generally, peaks occur in colder season, from November to May on the Northern Hemisphere (although April and May occur in a small area near Texas) and from June to September on the Southern Hemisphere. Pardé had two different types for this category – the temperate pluvial and the Mediterranean regimes. The peak is due to rainfall in the colder period and the minimum is in summer due to higher evapotranspiration and usually less rainfall.
The temperate pluvial regime (Beckinsale symbol CFa/b) usually has a milder minimum and the discharge is quite high also during the summer.
Meanwhile, the Mediterranean regime (Beckinsale symbol CS) has a more pronounced minimum due to a lack of rainfall in the region, and rivers have a noticeably smaller discharge during summer, or even dry up completely.
Beckinsale distinguished another pluvial regime, with a peak in April or May, which he denoted CFaT as it occurs almost solely around Texas, Louisiana and Arkansas.
Tropical pluvial regime
The name for the regime is misleading; the regime commonly occurs anywhere the main rainfall is during summer. This includes the intertropical region, but also includes parts influenced by monsoon, extending north even to Russia and south to central Argentina. It is characterized by a strong peak during the warm period, with a maximum from May to December on the Northern Hemisphere and from January to June on the Southern Hemisphere. The regime therefore allows for a lot of variation, both in terms of when the peak occurs and how low the minimum is.
Pardé additionally differentiated this category into two subtypes and Beckinsale split it into four. The most common such regime is Beckinsale's regime AM (for monsoon, as in Köppen classification), which is characterized by a period of low discharge for up to four months. It occurs in western Africa, the Amazon basin, and southeastern Asia.
In more arid areas, the period of low water increases to six, seven months and up to nine, which Beckinsale classified as AW. The peak is hence narrower and greater.
In dry climate, ephemeral streams that have irregular year-to-year patterns exist. Most of the time, it is dry and it only has discharge during flash floods. Beckinsale classifies it as BW, but only briefly mentions. Due to irregularity, the peak might be spread out or show multiple peaks, and could resemble other regimes.
The previous three regimes are all called intertropical by Pardé but the next is also differentiated by him as it has two maxima instead of one. He termed the name equatorial regime, while Beckinsale used the symbol AF. It occurs in Africa around Cameroon and Gabon, and in Asia in Indonesia and Malaysia, where one peak is in October/November/December and another in April/May/June, sort of being symmetrical for both hemispheres. Interestingly, the same pattern is not observed in South America.
Nival regime
Nival regime is characterized by a maximum which is contributed by the snow-melt as the temperatures increase above the melting point. Hence, the peaks occur in spring or summer. They occur in regions with continental and polar climate, which is on the Southern Hemisphere mostly limited to the Andes, Antarctica and minor outlying islands.
Pardé split the regimes into two groups: the mountain nival and the plain nival regimes, which Beckinsale also expanded. Plain regimes have maxima that are more pronounced and narrow, usually up to three months, and the minimum is milder and mostly not much lower from other months apart from the peak. The minimum, if the regime is not transitioning to a pluvio-nival regime, is usually quickly after the maximum, while for mountain regimes, it is often right before. Such regimes are exceptionally rare on the Southern Hemisphere.
Nival regimes are commonly intermittent in subarctic climate where the river freezes during winter.
Plain nival regime
Beckinsale differentiates six plain nival to nivo-pluvial regimes, mainly based on when the peak occurs. If the peak occurs in March or April, Beckinsale called this a DFa/b regime, which correlates to Mader's transitional pluvial regime. There, it is defined more precisely that the peak is in March or April, with the second highest discharge in the other of those months, not February or May. This translates to a peak in September or October on the southern hemisphere. This regime occurs in most European plains and parts of St. Lawrence River basin.
If the nivo-pluvial peak occurs later, in April or May (October or November on the Southern Hemisphere), followed by the discharge of the other month, the regime is transitional nival or DFb/c. This regime is rarer and occurs mostly in parts of Russia and Canada, but also at some plains at higher altitudes.
In parts of Russia and Canada and on elevated plains, the peak can be even later, in May or June (November or December on the Southern Hemisphere). Beckinsale denoted this regime with DFc.
Beckinsale also added another category, Dwd, for rivers that completely diminish during the winter due to cold conditions with a sharp maximum in the summer. Such rivers occur in Siberia and northern Canada. The peak can be from May to July on Northern Hemisphere or from November to January on Southern Hemisphere.
Apart from that, he also added another category for regimes with pluvio-nival or nivo-pluvial maxima where the pluvial maximum corresponds to a Texan or early tropical pluvial regime, not the usual temperate pluvial. This regime occurs in parts of PRC and around Kansas.
If this peak happens later, Beckinsale classified it as DWb/c. The peak can occur as late as September on the Northern Hemisphere or March on the Southern Hemisphere.
Mountain nival regime
Pardé and Beckinsale both assigned only one category to the mountain nival regime (symbol HN), but Mader distinguishes several of them. If the peak occurs in April or May on Northern Hemisphere and October or November on Southern Hemisphere with the discharge of the other of those two months following, it is called transitional nival, common for lower hilly areas.
If the peak is in May or June on the Northern Hemisphere, or November or December on Southern Hemisphere, followed by the other of those two, the regime is called mild nival.
The regime which Mader just calls 'nival' is when the highest discharge is in June/December, followed by July/January, and then May/November.
Nivo-glacial regime
The nivo-glacial regime occurs in areas where seasonal snow meets the permanent ice sheets of glaciers on top of mountains or at higher latitudes. Therefore, both melting of snow and ice from glaciers contribute to produce a maximum in early or mid summer. In turn, it could still be distinguished between plain and mountain regimes, but that distinction is rarely made despite being quite obvious. It is also characterized by great diurnal changes, and a sharp maximum. Pardé and Beckinsale did not distinguish this regime from glacial and nival regimes. Mader defines it as having a peak in June or July, followed by the other of the two, and then the August's discharge, which translates to a peak in December or January, followed by the other two and then February for Southern Hemisphere. Such regimes occur in the Alps, the Himalayas, Coast Mountains and southern Andes.
Plain nivo-glacial regimes occur on Greenland, northern Canada and Svalbard.
Glacial regime
The glacial regime is the most extreme variety of temperature-dependent regimes and occurs in areas where more than 20% of its catchment area is covered by glaciers. This is usually at altitudes over , but it can also happen in polar climates which was not explicitly mentioned by Pardé, who grouped both categories together. Rivers with this regime also experience great diurnal variations.
The discharge is heavily dominated by the melting of glaciers, leading to a strong maximum in late summer and a really intense minimum during the rest of the year, unless it has major lake storage, such as the Rhône after the Lake Geneva or the Baker River, which is shown below. Mader defines it to have the highest discharge in July or August, followed by the other month.
In really extreme cases (mostly on Antarctica), there could also be a plain glacial regime.
Mixed regimes
Mixed or double regimes are regimes where one peak is due to a temperature-dependent factor (snow or ice melt) and one is due to rainfall. There are many possible combinations, but only some have been studied in more detail. They can also be split into two categories – plain (versions of Beckinsale's plain nival regimes with another peak) and mountain. They can be in general thought of as combinations of two simple regimes but the cold-season pluvial peak is usually in autumn, not in late winter as is common for temperate pluvial regime.
Mixed regimes are usually split into two other categories: the nivo-pluvial and pluvio-nival regimes, the first having a nival peak in late spring (April to June on Northern Hemisphere, October to December on Southern Hemisphere) and the biggest minimum in the winter while the latter usually has a nival peak in early spring (March or April on Northern Hemisphere, September or October on Southern Hemisphere) and the biggest minimum in the summer.
Plain mixed regime
Beckinsale did not really classify the regimes by the number of factors contributing to the discharge, so such regimes are grouped with simple regimes in his classification as they appear in close proximity to those regimes. For all of his six examples, mixed regimes can be found, although for DFa and DWd, that is quite rare. In the majority of cases, they are nivo-pluvial with the main minimum in winter, except for DFa/b.
Mountain mixed regime
Mountain mixed regimes are thoroughly researched and quite common in the Alps, and rivers with such regimes rise in most mountain chains. Beckinsale does not distinguish them from plain regimes, however, they are classified rather different from his classification in newer sources.
Mader classifies mixed regimes with the nival peaks corresponding to mild nival or Mader's nival as 'winter nival' and 'autumn nival', depending on the pluvial peak. The winter peak is usually small. In monsoonal areas, the peak can be in summer as well.
Mader denoted only those regimes with nival peaks corresponding to transitional nival as 'nivo-pluvial'. Hrvatin in his distinction also differentiated between 'high mountain Alpine nivo-pluvial regime' and 'medium mountain Alpine nivo-pluvial regime', the first showing significant difference between the minima and the other not, although some regimes in his classification also have mild nival peaks. In Japan, the pluvial peak is in the summer.
In Mader's classification, any regime with a transitional pluvial peak is pluvio-nival. Hrvatin also defines it further with a major overlap to Mader's classification. If minima are rather mild, then it is classified as 'Alpine pluvio-nival regime', if minima are more pronounced but the peaks are mild, then it is classified as 'Dinaric-Alpine pluvio-nival regime' and if the peaks are also pronounced, then it is 'Dinaric pluvio-nival regime'. His 'Pannonian pluvio-nival regime' corresponds to a plain mixed regime. Japan has mixed regimes with tropical pluvial peak.
Complex regimes
Complex regimes is the catch-all category for all rivers where the discharge is influenced by many different factors that occur at different times of the year. For rivers that flow through many different climates and have many tributaries from different climates, their regime can become unrepresentative of any area the river's catchment area is in. Many of the world's longest rivers have such regimes, such as the Nile, the Congo, the St. Lawrence River and the Rhone. A special form of such regimes is the uniform regime, where all peaks and minima are extremely mild.
References
Bibliography
Rivers
Hydrology | Discharge regime | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 6,133 | [
"Hydrology",
"Environmental engineering"
] |
76,906,213 | https://en.wikipedia.org/wiki/Benjamin%20Muckenhoupt | Benjamin Muckenhoupt (December 22, 1933, Boston – April 13, 2020, Whippany, New Jersey) was an American mathematician, specializing in analysis. He is known for the introduction of Muckenhoupt weights.
Biography
After graduating in 1950 from Newton High School (renamed in 1974 Newton North High School), Benjamin Muckenhoupt matriculated at Harvard University. where he graduated in 1954 with an A.B. At Harvard, by his outstanding score on the 1954 William Lowell Putnam Competition, he became a Putnam Fellow. At the University of Chicago, he graduated in 1955 with an M.Sc. and in 1958 with a Ph.D. His Ph.D. thesis On certain singular integrals was supervised by Antoni Zygmund. In the department of the mathematics of Rutgers University, he was an associate professor from 1963 to 1970 and a full professor from 1970 to 1991, when he retired as professor emeritus. For many years, he suffered from progressive supranuclear palsy.
The main focus of Muckenhoupt's mathematical research was harmonic analysis and weighted norm inequalities. At the Institute for Advanced Study, he held visiting positions for the academic years 1968–1970 and 1975–1976. At the State University of New York at Albany he was a visiting professor for the academic year 1970–1971.
His doctoral students include Eileen Poiani.
Upon his death he was survived by his widow, a daughter, a son, and three grandchildren.
Selected publications
References
1933 births
2020 deaths
20th-century American mathematicians
21st-century American mathematicians
Mathematical analysts
Harvard University alumni
University of Chicago alumni
Rutgers University faculty | Benjamin Muckenhoupt | [
"Mathematics"
] | 334 | [
"Mathematical analysis",
"Mathematical analysts"
] |
76,906,298 | https://en.wikipedia.org/wiki/Katya%20Ravid | Katya Ravid is a Biochemistry and Cell Biology professor at Boston University Chobanian & Avedisian School of Medicine. Ravid received her Bachelor of Science, PhD, and doctoral degree from the Israel Institute of Technology. She then received her postdoctoral at the Massachusetts Institute of Technology. As of 2021, she has been the inaugural incumbent of the Barbara E. Corkey Professor of Medicine of Boston University. She's a member of the Boston University's Whitaker Cardiovascular Institute and the Boston University-Boston Medical Center (BU-BMC) Cancer Center.
As a researcher in the fields of biochemistry and oncology, Ravid's research is focused on the study of blood platelets, adenosine receptors, and megakaryocytes to aid cancer patients. Her research allowed her to obtain multiple grants and become the founder of different programs for Boston University.
Career
Boston University has recognized Ravid as being "nationally and internationally recognized" for her discoveries, extensive research, and association to other programs. Under the university's announcement for title as the inaugural incumbent of the Barbara E. Corkey Professor of Medicine, one of the discoveries she was acclaimed for was her discovery of unique transcriptional signature that dictate how platelet lineage undergoes specification early in her career.
Alongside her title of the inaugural incumbent of the Barbara E. Corkey Professor, she also became the founding director of the Evans Center for Interdisciplinary Biomedical Research in 2009. The Evans Center for Interdisciplinary Biomedical Research is affiliated with the Evans Medical Foundation (founded in 1975) and the Department of Medicine at the Boston Medical Center (formally the Evans Department of Medicine). The Evans Center for Interdisciplinary Biomedical Research's goal is to establish a center in which faculty from the Department of Medicine and other schools can collaborate to promote biomedical research and education.
Ravid is also the director for Boston University Interdisciplinary Biomedical Research Office (IBRO) that is funded by the Boston University's Office of Research and the Department of Medicine. Launched in 2015, the office seeks to foster and support different biomedical research programs in collaboration with faculty and other members of Boston University's medical center and the Charles River campuses (such as the Clinical Translational Science Institute).
She held the title of president for the Massachusetts Academy of Sciences (MAS) from 2018 to 2022.
She has been a reporter/researcher for the National Institute of Health (NIH) since 2018.
As an awardee of the American Heart Association's Strategically Focused Research Network Award since 2021, she has received extensive funding and support from the association for her lab. She is the co-director of a lab focused on cancer-associated thromboembolism as affected by health disparities in collaboration with the American Heart Association. Her lab is one of three to have received the Strategically Focused Research Network Award to search for disparities in cardio oncology. The other labs that received the award are found at the University of Pennsylvania, Augusta University, and the Medical College of Wisconsin. Funding for these labs is planned to continue being provided until July 2025.
News sources have highlighted Ravid's work for making new findings in the field of oncology. In 2021, Boston University's newspaper, The Brink, wrote about her research findings on the linkage between black cancer patients and their higher susceptibility to blood clots. This was one of the findings in the lab funded by the American Heart Association. In 2021, The American Association for the Advancement of Science's newsletter, EurekaAlert!, credited Dr. Ravid for her research and discovery of two drugs, PXS-LOX_1 and PXS-LOX_2, which can slow down the development of bone marrow cancer called primary myelofibrosis (PMF). EurekaAlert! stated that "these drugs are unique because they are able to inhibit their target, a protein called lysyl oxidase, with a combination of specificity and potency not seen in previously tested drugs."
Honors and Awards
2000-2005: She was awarded the Established Investigator Award by the American Heart Association.
2011-2019: She was a vice chair and key speaker for the Gordon Research Conference in 2011, 2013, 2015, and 2019. Primarily for the cell biology of megakaryocytes and platelets section of the conference.
2014: She was elected as a fellow of the American Association for the Advancement of Science.
2016: She was awarded the Fulbright Scholar Award and is the first biomedical researcher at Boston University to receive this award because of their extensive research on hematopoiesis and megakaryocytes.
2019: She became a named member of the magazine, The American Society for Biochemistry and Molecular Biology.
References
Living people
Boston University faculty
Biochemists
Year of birth missing (living people) | Katya Ravid | [
"Chemistry",
"Biology"
] | 972 | [
"Biochemistry",
"Biochemists"
] |
76,906,393 | https://en.wikipedia.org/wiki/Freya%20Blekman | Freya Blekman is a Dutch professor at the University of Hamburg and the lead scientist at Deutsches Elektronen-Synchrotron (DESY). She contributed to the discovery of the Higgs boson at CERN and has been endowed the Helmholtz Distinguished Professorship. Her individual work specializes in the physics and experimental aspects of elementary particles and fields, specifically looking at the top quark sector by using precision measurements.
Early life and education
Blekman was born in the Netherlands. She grew up with a relatively arts and social-sciences focused family. Her grandmother was more math-oriented, but was forced to quit studying after high school to support her brother. This event pushed Blekman to go to university herself and pursue the sciences.
As an undergraduate, she was a part of the University of Amsterdam Science Fair team that presented their experiments during the CERN 40th anniversary event in 1994, jumpstarting her future career at the company. While originally studying biology, Blekman ran into her physics teacher in the streets which convinced her to switch to studying physics. Following this undergraduate degree in physics, she received a Masters of Science at the University of Amsterdam in 2000 on R&D for the LHCb experiment at CERN. In 2005, she received her PhD at the University of Amsterdam, although most of the research was based at the D0 experiment at Fermilab in the United States. Her thesis addressed the measurement of top quark pair production in the all-hadronic channel using the D0 experiment.
Career and research
After receiving her PhD Blekman joined the Compact Muon Solenoid (CMS) experiment in 2005 as a postdoctoral researcher at Imperial College London from 2005 to 2007 and Cornell University from 2007 to 2010. As the only woman among 100 people at Imperial College London, Blekman focused on CMS software and triggers, particle flow, and tau identification. At Cornell she researched pixel detector commissioning and measuring of the top quark pair production cross section using the Large Hadron Collider (LHC), which was turning on for the first time.
Following her postdoc Blekman was an assistant professor at Vrije Universiteit Brussel from 2010 to 2014 before becoming an associate professor until 2018. She then became a full-time professor of Vrije from 2019 to 2021, where she researched physics beyond the standard model in the top sector. During her academic career, Blekman was a member of many notable societies, including the German Physical Society, Institute of Physics (UK), and Belgian and Dutch physics societies.
Blekman made considerable contributions within the team that worked to answer questions about dark matter, gravitational waves, quantum theories, and the physics of the Higgs-Boson. Blekman and her team at CERN discovered the new standard model of the Higgs-Boson, earning them the Science Magazine Breakthrough of the Year Award in 2012.
Blekman has led multiple large physics groups throughout her life. The most prominent international research team lead was her creation of the physics outreach activities of the CMS Collaboration, where she currently still holds the role as the first Physics Communication Officer. Within this role, Blekman is responsible for outreach and communication of 4000+ international scientists at CERN that publish 130+ scientific papers per year. She also holds the role as the convener of the "Beyond-Two-Generations" (B2G) physics group, which has over 250 members worldwide and has published over 60 journals. The group works to analyze new particles using heavy quarks and W/Z/H bosons.
Since 2021 Blekman has been a lead scientist at Deutsches Elektronen-Synchrotron (DESY) with joint appointment at the University of Hamburg via the Helmholtz Distinguished Professor Recruitment Initiative. In addition to full-time professorship, Blekman is also a visiting professor at Vrije Unversiteit Brussel and the University of Oxford. Her future work includes searching for signs of new physics by using the Large Hadron Collider (LHC) and the Future Circular e+e- Collider (FCC-ee) at CERN.
Publications
Blekman has a Hirsh index of 210 with over 1500 published works. The majority of her published work is within CMS or D0 collaboration. Her works currently have 62,439 citations. The most cited are:
Chatrchyan, S., et al. (2012). Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC. Physics Letters. Part B, 716(1), 30–61. https://doi.org/10.1016/j.physletb.2012.08.021
The CMS Collaboration. (2008). The CMS experiment at the CERN LHC. Journal of Instrumentation: An IOP and SISSA Journal, 3(08), S08004–S08004. https://doi.org/10.1088/1748-0221/3/08/s08004
Individually produced papers:
Blekman, F. (2005). Top Quark Pair Production in Proton Anti-Proton Collisions. OSTI.GOV. https://doi.org/10.2172/15017276
Blekman, F. (2012). Search for same-sign top production at the LHC. Societa Italiana di Fisica. 173–176. https://doi.org/10.1393/ncc/i2012-11241-6
Blekman, F. (2013). Measurement of the top pair invariant mass distribution and search for New Physics (CMS). Proceedings of Science. https://doi.org/10.22323/1.174.0212
Blekman, F. (2007). Studies for Semileptonic B Decays from B0. Proceedings of Science. https://doi.org/10.22323/1.021.0208
Blekman, F. (2007). Measurement of inclusive differential cross sections for Upsilon(1S) production in ppbar collisions at \sqrt s=1.96 TeV. Proceedings of Science. https://doi.org/10.22323/1.021.0234
Honors and awards
2011 – Odysseus II Grant by the Flemish funding agency FWO
2012 – Science Magazine/Breakthrough of the Year 2012 Award (for discovery of Higgs Boson)
2013 – USA Department of Energy LHC Physics Center Fellow
2013 – European Physics Society High Energy and Particle Physics (HEPP) prize for discovery of Higgs-boson (for CMS collaboration)
2016 – Jaarprijs Science Communication award of the Royal Flemish Academy of Belgium for the Arts and Sciences (KVAB) for promotion of particle physics on social media
2019 – European Physics Society High Energy and Particle Physics (HEPP) prize for physics of the Top quark (for D0 collaboration)
2019 – 2021 – USA Department of Energy LHC Physics Center Senior Distinguished Researcher
2021 – Helmholtz Distinguished Professorship
Memberships
1999 – Member of CERN student program
1999 – Chairperson of ATLAS-Canada Standing Review Committee, Natural Sciences and Engineering Research Council of Canada (NSERC), and Canada IPPP Durham Advisory Board
2016 – 2019 – Member and co-chairperson of the CMS publication committee on Supersymmetry
2014 – 2018 – President of the PR and Outreach Council, VUB Faculty of Science and Bioengineering
2016 – 2018 – Co-convener of the Top physics group for the future electron-positron collider FCC-ee study
2012–present – Convener of Beyond-Two-Generations (B2G) physics group
2018–present – First ever CMS Physics Communication Officer
2021–present – Lead Scientist at DESY
Social media coverage
Blekman is very active on X under the username @freyablekman, where she shares advancements in her work on particle physics. She was also featured at CERN in a YouTube series about the hadron collider restart in 2015. This promotion of particle physics on social media won her the Jaarprijs Science Communication award of the Royal Flemish Academy of Belgium for the Arts and Sciences (KVAB) in 2016.
References
Living people
University of Amsterdam alumni
Academic staff of Vrije Universiteit Brussel
Academic staff of the University of Hamburg
Dutch physicists
Dutch women physicists
Particle physicists
Year of birth missing (living people) | Freya Blekman | [
"Physics"
] | 1,801 | [
"Particle physicists",
"Particle physics"
] |
76,906,612 | https://en.wikipedia.org/wiki/Quantum%20metrological%20gain | The quantum metrological gain is defined in the context of carrying out a metrological task using a quantum state of a multiparticle system. It is the sensitivity of parameter estimation using the state compared to what can be reached using separable states, i.e., states without quantum entanglement. Hence, the quantum metrological gain is given as the fraction of the sensitivity achieved by the state
and the maximal sensitivity achieved by separable states. The best separable state is often the trivial fully polarized state, in which all spins point into the same direction. If the metrological gain is larger than one then the quantum state is more useful for making precise measurements than separable states. Clearly, in this case the quantum state is also entangled.
Background
The metrological gain is, in general, the gain in sensitivity of a quantum state compared to a product state. Metrological gains up to 100 are reported in experiments.
Let us consider a unitary dynamics with a parameter from initial state ,
the quantum Fisher information constrains the achievable precision in statistical estimation of the parameter via the quantum Cramér–Rao bound as
where is the number of independent repetitions. For the formula, one can see that the larger the quantum Fisher information, the smaller can be the uncertainty of the parameter estimation.
For a multiparticle system of spin-1/2 particles
holds for separable states, where is the quantum Fisher information,
and is a single particle angular momentum component. Thus, the metrological gain can be characterize by
The maximum for general quantum states is given by
Hence, quantum entanglement is needed to reach the maximum precision in quantum metrology. Moreover, for quantum states with an entanglement depth ,
holds, where is the largest integer smaller than or equal to and is the remainder from dividing by . Hence, a higher and higher levels of multipartite entanglement is needed to achieve a better and better accuracy in parameter estimation. It is possible to obtain a weaker but simpler bound
Hence, a lower bound on the entanglement depth is obtained as
Mathematical definition for a system of qudits
The situation for qudits with a dimension larger than is more complicated. In this more general case, the metrological gain for a given Hamiltonian is defined as the ratio of the quantum Fisher information of a state and the maximum of the quantum Fisher information for the same Hamiltonian for separable states
where the Hamiltonian is
and acts on the nth spin.
The maximum of the quantum Fisher information for separable states is given as
where and denote the maximum and minimum eigenvalues of respectively.
We also define the metrological gain optimized over all local Hamiltonians as
The case of qubits is special. In this case, if the local Hamitlonians are chosen to be
where are real numbers, and then
,
independently from the concrete values of . Thus, in the case of qubits, the optimization of the gain over the local Hamiltonian can be simpler. For qudits with a dimension larger than 2, the optimization is more complicated.
Relation to quantum entanglement
If the gain larger than one
then the state is entangled, and it is more useful metrologically than separable states. In short, we
call such states metrologically useful.
If all have identical lowest and highest eigenvalues, then
implies metrologically useful -partite entanglement. If for the gain
holds, then the state has metrologically useful genuine multipartite entanglement. In general, for quantum states holds.
Properties of the metrological gain
The metrological gain cannot increase if we add an ancilla to a subsystem or we provide an additional copy of the state.
The metrological gain is convex in the quantum state.
Numerical determination of the gain
There are efficient methods to determine the metrological gain via an optimization over local Hamiltonians. They are based on a see-saw method that iterates two steps alternatively.
References
Quantum information science
Quantum optics | Quantum metrological gain | [
"Physics"
] | 819 | [
"Quantum optics",
"Quantum mechanics"
] |
76,907,606 | https://en.wikipedia.org/wiki/NGC%201110 | NGC 1110 is a barred spiral galaxy located around 53 million light-years away in the constellation Eridanus. NGC 1110 was discovered on December 21, 1886 by the astronomer Francis Preserved Leavenworth, and has a diameter of 56,000 light-years. NGC 1110 is not known to have lots of star formation, and it is not known to have an active galactic nucleus.
References
External links
Barred spiral galaxies
Magellanic spiral galaxies
Eridanus (constellation)
1110
10673 | NGC 1110 | [
"Astronomy"
] | 103 | [
"Eridanus (constellation)",
"Constellations"
] |
76,908,060 | https://en.wikipedia.org/wiki/Dai%20Lixin | Dai Lixin (; 13 November 1924 – 13 May 2024) was a Chinese chemist, and an academic of the Chinese Academy of Sciences.
Biography
Dai was born in Beijing on 13 November 1924 and was raised at his ancestral home is in Jurong, Jiangsu. In 1936, when he studied at Yuying Middle School, the Second Sino-Japanese War broke out, and his family fled to their grandfather's house in the Shanghai French Concession. After graduating from Sanyu High School, he was accepted to the Department of Chemistry at Hujiang University in 1942. A year later, he transferred to the Department of Chemistry at Zhejiang University.
After graduating from university in 1947, Dai taught at Shanghai Zhonghua Vocational School for a short time. In 1948, he was introduced by his classmates to work in the laboratory of the 3rd Iron and Steel Plant located in Pudong. He joined the Chinese Communist Party (CCP) in 1949.
After the establishment of the Communist State in 1949, Dai successively worked at Shanghai Iron and Steel Company and East China Mining and Metallurgy Bureau. In 1953, he was transferred to the Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, and in 1958, he was engaged in scientific and technological organization related to organic chemistry in the "Two Bombs, One Satellite" project. In 1962, he independently carried out extensive work on borohydride reactions and chemical research on carboranes. During the ten-year Cultural Revolution, he was forced to perform hard labor instead of doing research in the laboratory. He was a victim of political persecution that affected other academics at the time. In 1978, he returned to his research position and served as an assistant to Wang You, director of the Shanghai Institute of Organic Chemistry at that time. He was promoted to doctoral supervisor in June 1986. In the 1990s, he and academician Huang Liang jointly led the major project of the Ninth Five Year Plan - "Chemical and Biological Research of Chiral Drugs".
On 13 May 2024, Dai died in Shanghai, at the age of 99.
Family
Dai married Dong Zhuxin () and had a daughter Dai Jing ().
Honours and awards
1993 - Member of the Chinese Academy of Sciences (CAS)
2002 - Science and Technology Progress Award of the Ho Leung Ho Lee Foundation
2013 - State Natural Science Award (Second Class) for asymmetric catalysis based on chiral phosphine nitrogen ligands.
2018 - Lifetime Achievement Award of the Chinese Chemical Society
References
1924 births
2024 deaths
Scientists from Beijing
Zhejiang University alumni
Members of the Chinese Academy of Sciences
Chinese organic chemists
20th-century Chinese scientists
21st-century Chinese scientists | Dai Lixin | [
"Chemistry"
] | 535 | [
"Organic chemists",
"Chinese organic chemists"
] |
76,908,226 | https://en.wikipedia.org/wiki/Huang%20Liang%20%28chemist%29 | Huang Liang (; 22 May 1920 – 21 November 2013) was a Chinese chemist, and an academician of the Chinese Academy of Sciences. She was a member of the 5th, 6th and 7th National Committee of the Chinese People's Political Consultative Conference.
Biography
Huang was born in Shanghai, on 22 May 1920. In 1938, she enrolled at St. John's University, Shanghai, where she majored in the Department of Chemistry. After university in 1942, Huang worked in Shanghai Biochemical Pharmaceutical Factory for a short time. In 1943, she successively taught at the Central Industrial Experimental Institute and the Department of Chemistry, Shanghai Medical University (now Shanghai Medical College, Fudan University).
In 1946, recommended by Professor Taykor, former head of the Department of Chemistry at St. John's University, Shanghai, she went to the Department of Chemistry at Cornell University in the United States to further studies and received a doctor degree in organic chemistry in 1949. She later worked in the laboratories of Bryn Mawr College (1949–1950), Cornell University (1950–1952), Wayne State University (1952–1954), and Iowa State University (1954–1956).
Huang returned to China in 1956 and in February 1957 worked in the Department of Pharmacy, Central Health Research Institute, which was reshuffled as the Institute of Materia Medica Chinese Academy of Medical Science in 1958. In 1960, she became director of Drug Synthesis Room, and served until 1983. During the ten-year Cultural Revolution, she forced to work in the fields instead of doing research in the laboratory. In the 1990s, she and academician Dai Lixin jointly led the major project of the Ninth Five Year Plan – "Chemical and Biological Research of Chiral Drugs".
On 21 November 2013, Huang died in the United States at the age of 93.
Contributions
Huang guided research and developed Jiangya Ling, the first blood pressure lowering drug in China.
Family
Huang was married to Liu Jinxu (; 1917–1997), an animal nutritionist.
Honours and awards
1958 Title of "National March-Eighth Red-Banner Pacesetter"
1980 Member of the Chinese Academy of Sciences (CAS)
1987 State Science and Technology Progress Award (Third Class) for synthesis and study of indigo red derivatives
1987 State Technological Invention Award (Third Class) for determination of the structure of a new anti tapeworm drug, hecao phenol.
1998 Science and Technology Progress Award of the Ho Leung Ho Lee Foundation
References
1920 births
2013 deaths
Scientists from Shanghai
St. John's University, Shanghai alumni
Cornell University alumni
Chinese organic chemists
Members of the Chinese Academy of Sciences
20th-century Chinese scientists
21st-century Chinese scientists
Members of the 5th Chinese People's Political Consultative Conference
Members of the 6th Chinese People's Political Consultative Conference
Members of the 7th Chinese People's Political Consultative Conference | Huang Liang (chemist) | [
"Chemistry"
] | 574 | [
"Organic chemists",
"Chinese organic chemists"
] |
76,909,249 | https://en.wikipedia.org/wiki/Dongfang%20Jingyuan%20Electron%20Limited | Dongfang Jingyuan Electron Limited (DJEL; ) is a Chinese semiconductor equipment and software company that specializes in integrated circuit yield management.
Background
In early 2014, former ASML employee Yu Zongchang founded two companies, DJEL in Beijing and Xtal in Silicon Valley. According to an attorney representing ASML, Yu was instructed by Han Jingyuan to create these companies. Han was chairman and CEO of China Oriental Group as well as holder of multiple roles in the Chinese Communist Party. According to Datenna, China Oriental Group through its subsidiaries owned more than 50% of DJEL until 2019 when it sold its stake to other investors.
In 2015, DJEL signed a research agreement with the Institute of Microelectronics of the Chinese Academy of Sciences. They created a joint venture for chip technology development.
In 2018, ASML sued Xtal and several employees for intellectual property theft. In the trial, ASML's attorney told the court that DJEL and Xtal worked together with the same goal of obtaining ASML's technology and transferring it to China to foster its own semiconductor industry. At the centre of the litigation was Optical proximity correction (OPC) software needed for lithography machines to print tiny circuits. One engineer was accused of stealing 2 million lines of source code for critical ASML software and then sharing it with DJEL and Xtal employees. Xtal lost and was ordered to pay $845 million. As a result, Xtal filed for bankruptcy. An arrest warrant was issued for Yu but he had already fled back to China.
Despite losing the Xtal case, the Chinese government granted DJEL a wide-ranging patent in 2019 that includes OPC software. In 2021, the Ministry of Industry and Information Technology announced that DJEL was named a "little giant", a designation often followed by significant new investment and expectations of rapid growth.
In its 2021 annual report, ASML mentioned that DJEL (which was affiliated with Xtal) was actively marketing products in China that could potentially infringe on ASML copyright. This was considered a risk factor to ASML. The Ministry of Foreign Affairs of the People's Republic of China called the allegations "malicious hype. ASML started investigation for evidence of intellectual property theft but has difficulties due to lack of response to its inquiries. ASML has told key customers not to aid DJEL in any way. DJEL stated its operations comply with relevant laws and regulations.
In May 2023, it was reported that DJEL was considering filing for an initial public offering as early as 2024. At the time. the company was valued at 8 billion yuan ($1.2 billion). One of the listing venues considered was the Shanghai Stock Exchange STAR Market.
In April 2024, DJEL completed another round of financing worth 1 billion yuan. Investors include Shenzhen Capital Group.
In December 2024, DJEL was targeted in a new round of US export controls and added to the United States Department of Commerce's Entity List.
See also
Semiconductor industry in China
ASML Holding
References
External links
2014 establishments in China
Companies based in Beijing
Electronics companies established in 2014
Equipment semiconductor companies
Semiconductor companies of China | Dongfang Jingyuan Electron Limited | [
"Engineering"
] | 642 | [
"Equipment semiconductor companies",
"Semiconductor fabrication equipment"
] |
76,909,281 | https://en.wikipedia.org/wiki/IC%201327 | IC 1327 is lenticular galaxy of type S0-a, located in the constellation Aquila. Its redshift is 0.032386, which corresponds IC 1327 to be located 445 million light-years from Earth. It has an apparent dimension of 0.90 x 0.8 arcmin, meaning the galaxy is 117,000 light-years across. IC 1327 was discovered on August 10, 1890, by Sherburne Wesley Burnham.
According to a study conducted in April 2006, IC 1327 is considered an isolated galaxy, which is included in early-type E-S0 galaxies that make up 14% of the isolated sample of galaxies in the local universe. Moreover, IC 1327 contains X-ray emission within a distance of 100 arcsec from the infrared position, which its structure is inspected in overlays on optical images.
References
1327
Aquila (constellation)
Lenticular galaxies
Astronomical objects discovered in 1890
065027
IRAS catalogue objects | IC 1327 | [
"Astronomy"
] | 203 | [
"Aquila (constellation)",
"Constellations"
] |
76,909,744 | https://en.wikipedia.org/wiki/Scrooge%20effect | The Scrooge effect is a psychological phenomenon that describes a noticeable behavioural change in individuals towards increased generosity and altruism following encounters with mortality or existential dread. It emphasizes that the realization of mortality motivates individuals to embrace cultural values and engage in activities that provide significance and transcendence beyond the concept of death. Corresponding to the terror management theory, the Scrooge effect proposes that existential apprehension can stimulate positive shifts in behavior. Individuals may prioritize acts of kindness and philanthropy as coping mechanisms to grapple with mortality and reaffirm their sense of purpose.
Empirical studies suggest that personal adversities such as severe illness, financial adversity, or the bereavement of a loved one can instigate pro-social conduct, fostering sentiments of generosity and empathy. The Scrooge effect offers a conceptual framework within psychology to examine the determinants influencing altruistic behaviors and the underlying mechanisms driving transformative experiences.
Ebenezer Scrooge
"A Christmas Carol" published in 1843 by Charles Dickens has become holiday classic which revolves around Ebenezer Scrooge, an elderly, rich man that the reader gets to know as being bitter and cold. During the night of Christmas Eve he is visited by three ghosts leaving him with lessons that guide Scrooge through a recognition. The ghost of Christmas Future reveals to Scrooge his future in which he passes away alone and mourned by no one.
This encounter reminds him to change his behavior by donating his money to charity, being kind to others and spending time with his family.
The character of Ebenezer Scrooge's transformation serves as a timeless reminder of the importance of redemption, compassion, reflection and the true meaning of the Christmas spirit. Charles Dickens' novel serves as a reminder of the true meaning of life and reminds the reader of the salience of mortality.
This novel critiques certain social aspects such as social injustice, poverty, inequality, and the dehumanizing effects of greed exemplifying the phenomenon of the Scrooge effect. Therefore, Charles Dickens' classic Christmas story connects to terror management theory and the Scrooge effect.
The terror management theory revolves around the idea that the thought of dying should encourage people to act pro-socially. In the case of the protagonist of this novel he is not following social norms in terms of kindness and empathy. When reminded of the loneliness of his own death, terror management theory comes into play and gives him a new perspective and what is important in life.
Studies
Dicken’s story hypothesizes the following consequence of mortality salience: Generous behaviour leads to the belief that one is a meaningful and valuable member in one’s own construct of the world and the confrontation with mortality should lead to kinder and more benevolent acts. This hypothesis was tested by Pyszczynki et al. in the U.S. in 1996. 17 male and 14 female participants were interviewed about the importance of several charities, either directly in front of a funeral home or a few blocks away. Results showed that people with the direct view of the funeral home were more likely to rate the charities favourably. Just like Dicken’s Mr. Scrooge, people that are confronted with their own mortality, in this case by standing in front of a funeral home, view giving to charities in a more favourable light.
Pyszczynski et al. found that there is some form of in-group favouritism concerning the choice of charity. 27 introductory psychology students of which 18 were female and 9 male were given 1.50$ as a “compensation” at the beginning of the study and were offered to donate a small amount of money to the charity of their choice later in the experiment. People gave more money to an American house-building charity than to an international education charity. This is why one has to keep in mind that there are limitations to the Scrooge effect. Ingroup favouritism in relation to mortality salience was also demonstrated in further studies.
Based on the research of Pyszczynski et al. in 1996, another study was conducted by Zaleskiewicz et al. in 2014 to investigate the Scrooge effect further using the dictator game (Study 1), the ultimatum game (Study 2) and a quasi-naturalistic situation (Study 3). They hypothesized that reminders of one’s own mortality would increase prosocial behaviour, leading to more generous distribution of financial resources and such behaviour would in turn suppress death-related thoughts. Again, this is what Mr. Scrooge is trying to cause. Mortality salience predicted the amount of money sent to the other player in the games, what is interpreted as higher joy solely from giving. These studies were specifically designed to investigate only the Scrooge effect. Since this phenomenon is connected to terror management theory, investigations commonly link the effect with the theory.
Terror Management Theory
The Scrooge effect, a concept that delves into the correlation between human behavior and the realization of one's own mortality, can be explained by the Terror Management Theory (TMT). It states that people's innate fear of dying leads them to look for strategies to satisfy their death anxiety by preserving their cultural values and beliefs. Acting in a prosocial way as well as dedicating yourself to religious beliefs are two of the main strategies for managing this anxiety. These observations were established through questionnaires about views relating to death and spirituality which were filled out by patients facing a life-threatening illness. Results confirmed that religious beliefs buffer the anxiety concerning the topic of death and decrease the likelihood of depressive symptoms.
The Scrooge Effect is a sensation that shows the impact of TMT on prosocial behavior. TMT proposes that existential anxiety is triggered by reminders of mortality, like those felt by Scrooge. People frequently look to their cultural worldview and look for ways to reinforce their significance within it to diminish this anxiety.
Individuals may feel more inclined to cooperate, show kindness, and be generous when they are made aware of their own death, whether consciously or unconsciously. These actions support a feeling of meaning and purpose in life to being in line with cultural norms and values. People reduce existential anxiety by affirming their worth and significance through helping others and improving their community. Life threatening events have the power to change an outlook on life; this is suggested by the study conducted before and during the COVID-pandemic. The results depict a significant rise in mortality salience. This is a prime example of TMT and the Scrooge effect. The anxiety concerning death and their own mortality also lead to an increase in prosocial behavior and a decrease of interest in materialistic properties.
TMT suggests that exhibiting prosocial conduct can offer a feeling of symbolic immortality. Humans can find some psychological solace in the face of mortality when they leave a positive legacy that transcends their physical life and benefits others or society at large.
Other studies suggest that mortality salience may not influence positive reciprocity, but has an impact on negative reciprocity (and on retaliation rather than altruism), which raises questions of the effect’s universality, and whether or not this effect is context dependent. Further research has shown that existential anxiety amplifies different radical behaviors, both positive, such as the search for meaning and negative, such as terrorism and religious fanaticism.
References
Psychological effects
A Christmas Carol
Philanthropy
Altruism | Scrooge effect | [
"Biology"
] | 1,528 | [
"Philanthropy",
"Behavior",
"Altruism"
] |
76,909,851 | https://en.wikipedia.org/wiki/ACM%20Research | ACM Research, Inc. (ACMR) is a publicly traded American semiconductor company that engages in the manufacture and sale of single-wafer wet cleaning equipment used to improve product yield.
Although based in the U.S., the majority of the company's business is done in China through its subsidiary, ACM Research (Shanghai).
Background
ACMR was founded in 1998 by David Wang. Wang is credited with inventing stress-free copper polishing technology.
Initially the tools were position as a competitor to chemical metal planarization but did not find any success. Due to strong backing, ACMR pivoted and shifted focus to wafer cleaning by carving out a niche.
In 2005, ACMR and Shanghai Venture Capital Co. established a joint venture in Shanghai named ACM Research (Shanghai). It would become majority owned by ACR and all major operations were eventually moved to China.
The first major customer for ACMR was SK Hynix who started placing orders for its cleaning tools in 2013. ACM's proprietary technology, Space Alternated Phase Shift (SAPS) has been shown to be more effective at removing random defects on wafers than jet spray or conventional megasonic cleaning technologies.
In November 2017, ACMR held its initial public offering and became a publicly listed company on the Nasdaq exchange.
In December 2017, ACMR formed ACM Research Korea to better service SK Hynix and would focus on hardware design and manufacture.
In November 2021, ACMR (Shanghai) listed on the Shanghai Stock Exchange STAR Market.
In March 2022, the U.S. Securities and Exchange Commission named ACMR as a company that faced delisting if it didn't hand over detailed audit documents to support its financial statement. This came as a result of the Holding Foreign Companies Accountable Act. ACMR's stock price dropped 27% as a result. In response, ACMR changed its auditor from BDO China Shu Lun Pan in Shenzhen to Armanino in San Ramon, California so it would no longer be subject to the related delisting guidelines.
In April 2022, ACMR planned to build a fab equipment plant in Korea. It was speculated this was done to avoid being involved the China–United States trade war.
In December 2024, ACMR was targeted in a new round of US export controls and added to the United States Department of Commerce's Entity List.
Key customers of ACMR include SK Hynix, SMIC, Hua Hong Semiconductor and Yangtze Memory Technologies. Apart from wafer cleaning, ACMR also has success in other areas such as electroplating for packaging firms.
See also
SK Hynix
Semiconductor industry in China
References
External links
1998 establishments in California
2017 initial public offerings
Companies based in Fremont, California
Companies listed on the Nasdaq
Companies listed on the Shanghai Stock Exchange
Equipment semiconductor companies
Semiconductor companies of China
Technology companies based in the San Francisco Bay Area
Computer companies of the United States
Semiconductor companies of the United States | ACM Research | [
"Engineering"
] | 622 | [
"Equipment semiconductor companies",
"Semiconductor fabrication equipment"
] |
76,910,147 | https://en.wikipedia.org/wiki/Valentina%20Fedorets | Valentina Aleksandrovna Fedorets (Russian: Валентина Александровна Федорец) was a Soviet astronomer.
Life
Valentina Fedorets was born in 1923 and died in 1976. The Venusian crater Fedorets is named in her honor.
References
Soviet astronomers
Women astronomers
1976 deaths
1923 births | Valentina Fedorets | [
"Astronomy"
] | 81 | [
"Women astronomers",
"Astronomers"
] |
76,910,391 | https://en.wikipedia.org/wiki/CO2-Plume%20Geothermal | {{DISPLAYTITLE:CO2-Plume Geothermal}}
-Plume Geothermal (CPG) is a proposed technology that combines Carbon Capture and Storage (CCS) with geothermal energy extraction, utilising itself as a geothermal energy extraction fluid.
Technology
First, would be injected in deep and naturally permeable reservoirs, just like in CCS, where the would be heated by the surrounding hot rocks. At a nearby location, production wells would then extract the geothermally heated supercritical back to the land surface, where it would be expanded in a turbine to generate electricity. The would then cooled and condensed back to a dense phase and re-injected into the reservoir, closing the cycle and enabling all to be permanently sequestered. CPG has the potential to generate over twice the power of conventional, water-based geothermal systems for similar conditions: while the specific heat capacity of is less than that of water, the significantly lower dynamic viscosity of would enable higher overall energy extraction rates.
Over 14 peer reviewed publications have been published on CPG as of 2024 since its invention by Martin Saar and Jimmy Randolph in 2011.
Relation to CCS projects
As the subsurface reservoir cools due to geothermal heat extraction, the density of in the subsurface increases, enabling a larger mass to be stored for a given formation. Other identified impacts of CPG on CCS include increased control over volumetric sweep, reduced carbon intensity of storage due to renewable energy production, additional monitoring data from production wells, flexibility to repurpose producer wells to injectors, avoiding injector downtime with associated halite deposition risks, and providing communities with power produced using .
Research needs
While existing equipment from EOR and CCS projects could be repurposed for CPG, new equipment is required, primarily lower temperature supercritical turbines and high-pressure cooling and condensing units. Selecting suitable locations is a challenge.
References
Carbon capture and storage
Emissions reduction
Gas technologies
Climate change mitigation
Applications of carbon dioxide
Industrial processes
Power station technology
Sustainable energy | CO2-Plume Geothermal | [
"Chemistry",
"Engineering"
] | 423 | [
"Greenhouse gases",
"Geoengineering",
"Carbon capture and storage",
"Emissions reduction"
] |
76,910,395 | https://en.wikipedia.org/wiki/Bernard%20G%C3%A8ze | Bernard Gèze (March 24, 1913 – December 8, 1996) was a French geologist, hydrogeologist, volcanologist, and speleologist.
Biography
Bernard Gèze was born on March 24, 1913, in Toulouse. In 1931, he enrolled in the National Agronomic Institute in Paris and graduated as an agronomist three years later. He worked as an assistant to Prof.Camille Arambourg and then, in 1936, to his successor, Prof. Pierre Lamare. During this time, he obtained a bachelor's degree in Natural Sciences from the Sorbonne University. In 1937, he earned his higher education diploma. At the beginning of the war, he served as a geological officer in the Army Corps of Nancy. As an assistant to Prof. Paul Fallot at the Collège de France in 1942, he prepared his thesis on the Montagne Noire, which he defended in 1949. He became a lecturer and then a professor of geology at the National School of Agriculture in Montpellier. He succeeded Prof. Lamare in 1954 at the Agronomy Institute, where he remained until his retirement in 1982.
In 1954, he became president of the French Geological Society. He was a corresponding member and then a full member of the French Academy of Agriculture.
Bernard Gèze died on December 8, 1996, in 5th arrondissement of Paris.
Speleological Work
Bernard Gèze pioneered scientific speleology in France, focusing on karst and hydrogeology since the 1940s.
On , he was one of the founders of the Spéléo-club de France, which became the Société spéléologique de France on . In 1936, he was also one of the founding members of the Spéléo-club de Paris. In 1945, with Louis Fage, René Jeannel, Félix Trombe, Albert Vandel, among others, he founded a speleology commission within the CNRS, which he chaired from 1965 to 1976. During the same period, the Bureau de recherches géologiques et géophysiques entrusted Gèze with compiling a directory of natural cavities. He was also part of the hydrology section of the French National Committee for Geodesy and Geophysics. He became director of the underground laboratory of Moulis.
With the support of these organizations and figures, Bernard Gèze founded the Annales de spéléologie in 1946, which constituted the third series of Spelunca, under the joint label of the SSF and the CAF.
In 1953, he was the secretary general of the first International Congress of Speleology in Paris, and then in 1963, he was one of the founders of the French Speleological Federation, and in 1965 in Postojna (Slovenia), of the International Union of Speleology, of which he was director until 1973 when he became honorary president.
He participated in famous underground explorations: Henne Morte (1946), Rognès shaft (1948), Penne Blanque chasm (1955), Padirac chasm (1952), among others. A room in the Orgnac Cave is named after him.
Honors
Knight of the Legion of Honour
Knight of the Order of Academic Palms
Officer of the Order of Agricultural Merit
Officer of the Order of Sports Merit
Honorary member of the French Federation of Speleology
Honorary president of the International Union of Speleology
Grand Medal of the Club Cévenol
Publications
1937 – "Étude hydrogéologique et morphologique de la bordure sud-ouest du Massif central," Ann. Inst. nat. agronomique tome XXIX, Paris, 80 p.
1939 – "Influence de la tectonique sur la localisation des sources vauclusiennes," Actes du Congrès national de spéléologie de Mazamet
1943 – "Géographie physique et géologie du Cameroun occidental," Mém. Mus. nat. Hist. nat. tome 17, 172 p.
1947 – "Paléosols et sols dus à l'évolution actuelle," Ann. Ecole nat. Agriculture Montpellier tome XXVII fascicule IV, Montpellier, 25 p.
1948 – "La capture souterraine du Thoré (versant atlantique) par le Jaur (versant méditerranéen)," Ann. Spéléologie tome III fascicule 4,
1949 – "Méthode d'étude de la zonalité pédogénétique par la paléopédologie," C. R. Acad. Sci., Paris, tome 228,
1949 – "Étude géologique de la Montagne Noire et des Cévennes méridionales," Mém. Soc. géol. France, , 215 p.
1952 – "Sur le sens de déversement des nappes de la Montagne Noire," Bull. Soc. géol. France, (6) tome II,
1953 – "Allocution présidentielle: La genèse des gouffres," Premier congrès international de spéléologie, tome II - Communications; Section I - Hydrogéologie et Morphologie karstique, Paris,
1953 – "Les volcans du Cameroun occidental," Bull. Volcanol. (II) tome XIII, Naples,
1955 – "Le volcanisme des Causses et du Bas-Languedoc (France)," Bull. Volcanol. (II) tome XVII, Naples,
1959 – "Les volcans du Tibesti (Sahara du Tchad)," Bull. Volcanol. (II) tome XXII, Naples,
1960–63 – "Caractères structuraux de l'arc de Nice (Alpes maritimes)," Livre mém. Paul Fallot, Mémoire hors série tome II, Société géologique de France, Paris,
1965 – La Spéléologie scientifique, Éditions du Seuil, Paris
1974 – La « geste » de Robert de Joly, explorateur d'abîmes, Chez Pierre Fanlac, Périgueux
1976 – "Aquitaine orientale," Guides géologiques régionaux, Éd. Masson, Paris
1979 – "Languedoc méditerranéen," Guides géologiques régionaux, Éd. Masson, Paris
1985 – "Origines et évolution de la géospéléologie française", Travaux du Comité français d'histoire de la géologie, tome III, Paris
1986 – "La géologie dans les romans de Jules Verne", Travaux du comité français d'histoire de la géologie, tome IV, , Paris,
1991 – "Présidents à gratter", Travaux du comité français d'histoire de la géologie, tome V, , Paris,
1994 – "Analyse d'ouvrage :"Cent ans de spéléologie française"", Spelunca–Mémoire, , Lyon & Travaux du comité français d'histoire de la géologie, tome VIII, , Paris,
1994 – "La ruée vers le phosphate dans les cavernes du Midi de la France", Travaux du comité français d'histoire de la géologie, tome VIII, , Paris,
1997 – "La ruée vers le phosphate dans les cavernes du Midi de la France," De la géologie à son histoire, Comité des travaux historiques et scientifiques, Paris, section des Sciences, vol. 13, (posthumously)
References
Bibliography
Chabert, C. (1997) - « Obituaire : Bernard GEZE (1913–1996) », [http://anar.ffs.free.fr/Bulletins/ANAR_Bull_02.pdf ANAR Bull' ], Association nationale des anciens responsables de la FFS, Lyon,
Durand-Delga, M. (1997) - « À travers Bernard Gèze (1913-1996) : aspects de la géologie parisienne au milieu du siècle », Travaux du Comité français d'histoire de la géologie'', tome XI, Paris
External links
Bernard GÈZE (March 24, 1913, Toulouse / December 8, 1996) at the Club loisirs et plein air (C.L.P.A.), spéléo section, of Montpellier
20th-century French geologists
20th-century French engineers
Civil engineers
Agricultural engineers
French volcanologists
French speleologists
Knights of the Legion of Honour
Officiers of the Ordre des Palmes Académiques
1913 births
1996 deaths | Bernard Gèze | [
"Engineering"
] | 1,822 | [
"Civil engineering",
"Civil engineers"
] |
76,910,742 | https://en.wikipedia.org/wiki/Bifurcaria%20galapagensis | Bifurcaria galapagensis, the Galapagos stringweed, is a species of brown algae seaweed endemic to the Galapagos Islands. The IUCN Red List categorized the algae as Critically Endangered (Possibly Extinct), after a March 2007 assessment noted that the plant hadn't been since 1983.
William Randolph Taylor documented Galapagos stringweed (then Blossevillea galapagensis) alongside myriad other Pacific marine algae during a three-month expedition to Baja California, Central and South America, and the Galapagos Islands. In the intertidal zones of Isla Santa Maria, Taylor notes that "[t]he dominant algal species appeared to be Blossevillea galapagensis, a notable fucoid endemic known from the time of the Vettor Pisani Expedition. This grew high on the littoral rocks in great abundance." Taylor notes seven separate expeditions from 1872 to 1934 (including his own) that found this species.
Before its disappearance, there was some evidence to suggest that Galapagos stringweed had both antimicrobial and antimitotic properties.
Description
Taylor described Bifurcaria galapagensis:Plants gregarious, olivaceous, firm in texture, black and brittle when dried, exceeding 4 dm in height, the basal holdfasts small, irregularly lobed; branching close to the base into several main axes which are about 1.0-1.5 mm diam., and which branch irregularly into smaller divisions, especially above bearing scattered lateral determinate aculeate to filiform branchlets 1-3 cm long; above irregularly dichotomously branched, the sterile divisions slender, near the top somewhat fastigiate; fertile branches dichotomously or sometimes laterally branched, the divisions nodulose, to 2.5 mm diam., tapering, the conceptacles hermaphrodite, the oval sporangia 133-200 μ long, 46-80 μ diam., each producing one egg.
Taxonomy
The classification of Bifurcaria galapagensis is uncertain, likely in part due to its scarcity; noted AlgaeBase founder M.D. Guiry points out that as of December 2017, members of the genus Bifurcaria are found only in the eastern Atlantic. This species was first classified as Fucodium galapagense in 1886 as it was apparently similar to F. tuberculatum. Bifurcaria galapagensis has several homotypic synonyms as its genus has been reassessed:
Pelvetia galapagensis (Piccone & Grunow) De Toni 1895
Blossevillea galapagensis (Piccone & Grunow) W.R. Taylor 1945: Based on similarities between "fructiferous parts and ha[ving] but one egg in each sporangium," Taylor decided that Galapagos stringweed was more closely related to Blossevillea brandegeei Setch & Gardner 1913 than to Bifurcaria or Pelvetia.
Likely extinction
Researchers applying a key biodiversity area (KBA) methodology to the Galapagos Marine Reserve conducted numerous field surveys between 2000 and 2006 were unable to find a single B. galapagensis specimen. The researchers considered "crypsis or insufficient search effort" as possible reasons for their inability to locate sought-after species but determined that "a lack of sighting ... reflect[ed] true absence[.]" Bifurcaria galapagensis was later described—by many of the same researchers—as "regarded as probably extinct". The Spring/Summer 2010 issue of Galapagos News lamented that "[o]ne in five of the marine species listed as threatened in Galapagos may already be extinct" and that "[i]t may be too late to save the endemic Galapagos stringweed[.]"
References
Further reading
The Galapagos: Proceedings of the Symposia of the Galapagos International Scientific Project (1966) edited by Robert I. Bowman, University of California Press, Berkeley and Los Angeles. See chapter 19, "Status of our Knowledge of the Galapagos Benthic Marine Algal Flora Prior to the Galapagos International Scientific Project" by Paul C. Silva. Includes a table of Galapagos expeditions from Darwin until the date of publication, a list of scientific literature cited, a chart detailing all 311 then-known regional algae.
Holocene Extinctions (2009) edited by Samuel T. Turvey, Oxford University Press. See chapter 6, "Holocene extinctions in the sea" by Nicholas K. Dulvy, John K. Pinnegar, and John D. Reynolds, especially chapter 6.8, "A brief overview of known marine extinctions."
Seaweeds
Fucales | Bifurcaria galapagensis | [
"Biology"
] | 996 | [
"Seaweeds",
"Algae"
] |
76,910,966 | https://en.wikipedia.org/wiki/GS-9209%20%28galaxy%29 | GS-9209 is a massive quiescent galaxy that exists at redshift z=4.658 or 25 billion light years. It has a stellar mass of which is roughly 10 times the mass of the Milky Way galaxy.
When the universe was around 800 million years old, the star formation rate (SFR) in the GS-9209 galaxy has undergone a sharp decrease. Most of the stars that exist in this galaxy has formed over a 200 million year period when the universe was 600-800 million years old.
Notes
References
Galaxies | GS-9209 (galaxy) | [
"Astronomy"
] | 114 | [
"Galaxies",
"Galaxy stubs",
"Astronomical objects",
"Astronomy stubs"
] |
76,911,793 | https://en.wikipedia.org/wiki/Leptodontidium%20trabinellum | Leptodontidium trabinellum is a species of fungus in the family Leptodontidiaceae.
References
Helotiales
Fungus species
Fungi described in 1869
Taxa named by Petter Adolf Karsten | Leptodontidium trabinellum | [
"Biology"
] | 45 | [
"Fungi",
"Fungus species"
] |
76,913,611 | https://en.wikipedia.org/wiki/Milnor%20conjecture%20%28Ricci%20curvature%29 | In 1968 John Milnor conjectured that the fundamental group of a complete manifold is finitely generated if its Ricci curvature stays nonnegative. In an oversimplified interpretation, such a manifold has a finite number of "holes". A version for almost-flat manifolds holds from work of Gromov.
In two dimensions has finitely generated fundamental group as a consequence that if for noncompact , then it is flat or diffeomorphic to , by work of Cohn-Vossen from 1935.
In three dimensions the conjecture holds due to a noncompact with being diffeomorphic to or having its universal cover isometrically split. The diffeomorphic part is due to Schoen-Yau (1982) while the other part is by Liu (2013). Another proof of the full statement has been given by Pan (2020).
In 2023 Bruè, Naber and Semola disproved in two preprints the conjecture for six or more dimensions by constructing counterexamples that they described as "smooth fractal snowflakes". The status of the conjecture for four or five dimensions remains open.
References
Differential geometry
Riemannian manifolds
Disproved conjectures | Milnor conjecture (Ricci curvature) | [
"Mathematics"
] | 253 | [
"Space (mathematics)",
"Riemannian manifolds",
"Metric spaces",
"Topology stubs",
"Topology"
] |
76,914,690 | https://en.wikipedia.org/wiki/CYP197%20family | Cytochrome P450, family 197, also known as CYP197, is a cytochrome P450 monooxygenase family. The first gene identified in this family is the CYP197A1 from Bacillus halodurans. CYP197 is one of the only three P450 families shared in bacteria and archaea, the other two are CYP147 and CYP109. Genes in this family are co-present on archaeal plasmids and chromosomes, implying the plasmid-mediated horizontal gene transfer of these genes from bacteria to archaea.
References
197
Protein families | CYP197 family | [
"Biology"
] | 134 | [
"Protein families",
"Protein classification"
] |
76,914,806 | https://en.wikipedia.org/wiki/CYP147%20family | Cytochrome P450, family 147, also known as CYP147, is a cytochrome P450 monooxygenase family. The first gene identified in this family is the CYP147B1 from Streptomyces avermitilis. CYP147 is one of the only three P450 families shared in bacteria and archaea, the other two are CYP197 and CYP109.
References
147
Protein families | CYP147 family | [
"Biology"
] | 99 | [
"Protein families",
"Protein classification"
] |
76,914,824 | https://en.wikipedia.org/wiki/2MASS%20J05352184%E2%88%920546085 | 2MASS J05352184-0546085, abbreviated to 2M0535-05 and also known by its variable star designation V2384 Orionis, is a young eclipsing binary brown dwarf system in the Orion Nebula, about away. It was discovered in 2006 and was the first eclipsing brown dwarf system to be discovered, predating the discovery of the transiting brown dwarf CoRoT-3b in 2008.
The pair orbit each other with a period of 9.8 days, and are about 60 and 38 times the mass of Jupiter, respectively. The system is very young, at an age of about 1 million years, so the brown dwarfs have yet to cool; they are M-type objects with temperatures comparable to red dwarf stars, and they are inflated in size to over half the radius of the Sun. The primary is observed to rotate with a period of 3.3 days and the secondary 14 days, indicating that they have not yet become tidally locked to each other.
Unexpectedly, the less massive (secondary) brown dwarf is the hotter of the pair. Possible explanations for this temperature reversal include the two brown dwarfs differing slightly in age; strong magnetic fields on the primary inhibiting convection, supported by the primary's observed fast rotation and strong hydrogen-alpha emission; large starspots on the primary, though this was found to be unsupported by evidence; and tidal heating, which is unlikely to be solely responsible for the temperature reversal.
No infrared excess that would indicate the presence of a circumstellar disk has been detected in this system.
See also
2M1510, another eclipsing binary brown dwarf
Notes
References
Further reading
Orion (constellation)
Orion molecular cloud complex
Eclipsing binaries
M-type brown dwarfs
J05352184-0546085
Orionis, V2384
Astronomical objects discovered in 2006 | 2MASS J05352184−0546085 | [
"Astronomy"
] | 389 | [
"Constellations",
"Orion (constellation)"
] |
76,916,306 | https://en.wikipedia.org/wiki/IC%204481 | IC 4481 is a type SBbc barred spiral galaxy located in Boötes. Its redshift is 0.110727, meaning IC 4481 is located 1.49 billion light-years away from Earth. It is one of the furthest objects in the Index Catalogue and has an apparent dimension of 0.30 x 0.2 arcmin. IC 4481 was discovered on May 10, 1904, by Royal Harwood Frost, who found it "faint, very small, round and diffuse".
See also
List of the most distant astronomical objects
References
4481
Barred spiral galaxies
1501729
Boötes
Discoveries by Royal Harwood Frost
Astronomical objects discovered in 1904 | IC 4481 | [
"Astronomy"
] | 140 | [
"Boötes",
"Constellations"
] |
76,916,616 | https://en.wikipedia.org/wiki/IC%203447 | IC 3447 (or PGC 165209) is a type Sc barred spiral galaxy located in the constellation Virgo. It has a redshift of 0.092479, which means IC 3447 is 1.27 billion light-years from Earth, making it one of the furthest objects in the Index Catalogue. The galaxy has apparent dimensions of 0.30 x 0.3 arcmin, which means IC 3447 is 111,000 light-years across. It was discovered by Royal Harwood Frost on May 10, 1904.
References
3447
Virgo (constellation)
Barred spiral galaxies
165209
Discoveries by Royal Harwood Frost
Astronomical objects discovered in 1904 | IC 3447 | [
"Astronomy"
] | 139 | [
"Virgo (constellation)",
"Constellations"
] |
76,916,676 | https://en.wikipedia.org/wiki/West%20African%20Conservation%20Network | West African Conservation Network (WACN) is a non-profit organization established by Patrick Ogbonnia Egwu, with a primary mission of preserving and restoring wilderness areas.
Location
WACN has its headquarters on the 7th Floor of Mulliner Towers, Alfred Rewane Road Lagos, 101233, Nigeria and Kemp House, City Road, London, EC1V 2NX, United Kingdom.
Overview
WACN was established in August 2020. With an emphasis on collaboration with governmental entities, the organization seeks to address the decline of wilderness regions, aspiring to transform them into sustainable ecosystems. The organization endeavors to promote sustainability within these habitats through strategic initiatives, aiming to ensure their long-term viability for future generations. WACN's mission centers on the restoration and protection of depleted wilderness areas. This mission entails establishing agreements with governmental authorities governing the respective jurisdictions of these wilderness areas. Utilizing meticulous protection measures and strategic reintroduction efforts, WACN endeavors to reverse the decline of biodiversity within these regions, to restore them to their original levels of ecological integrity.
Projects
Kainji Lake National Park
On the 27th of October 2023, WACN signed a 31 years memorandum of understanding with the Nigeria National Park Service to restore, secure and manage the Kainji Lake National Park which is a 2000+ square mile (5000+ square kilometers) wilderness area straddling Niger and Kwara states, in the northwestern part of the country. It was one of several MOUs signed by the National Park Service with various organisations to strengthen conservation efforts.
References
Non-profit corporations
Ecological restoration
Organizations based in Africa
Nature conservation in Africa
Nature conservation organizations based in Africa | West African Conservation Network | [
"Chemistry",
"Engineering"
] | 340 | [
"Ecological restoration",
"Environmental engineering"
] |
76,916,780 | https://en.wikipedia.org/wiki/NGC%203950 | NGC 3950 is an elliptical galaxy of type E, in Ursa Major. Its redshift is 0.074602, meaning NGC 3950 is 1.03 billion light-years or 316 Mpc from Earth, which is within the Hubble distance values. This high redshift makes NGC 3950 one of the furthest New General Catalogue objects.
NGC 3950 has apparent dimensions of 0.30 x 0.3 arcmin, meaning the galaxy is 90,000 light-years across. It was discovered by Lawrence Parsons on April 27, 1875, and he described it as, "extremely faint, 2.6 arcmin north of h 1009".
In a research article published in 1990, NGC 3950 was believed to be a dwarf galaxy, and a close companion of a larger spiral galaxy, NGC 3949. But further research involving measuring its redshift in 2005 showed NGC 3950 is much further away in the background. Together with NGC 3949, they both form an optical galaxy pair called HOLM 301.
References
3950
Ursa Major
Elliptical galaxies
Discoveries by Lawrence Parsons
Astronomical objects discovered in 1875
037294
+08-22-030 | NGC 3950 | [
"Astronomy"
] | 241 | [
"Ursa Major",
"Constellations"
] |
76,916,805 | https://en.wikipedia.org/wiki/Anafunctor | An anafunctor is a notion introduced by for ordinary categories that is a generalization of functors. In category theory, some statements require the axiom of choice, but the axiom of choice can sometimes be avoided when using an anafunctor. For example, the statement "every fully faithful and essentially surjective functor is an equivalence of categories" is equivalent to the axiom of choice, but we can usually follow the same statement without the axiom of choice by using anafunctor instead of functor.
Definition
Span formulation of anafunctors
Let and be categories. An anafunctor with domain (source) and codomain (target) , and between categories and is a category , in a notation , is given by the following conditions:
is surjective on objects.
Let pair and be functors, a span of ordinary functors (), where is fully faithful.
Set-theoretic definition
An anafunctor following condition:
A set of specifications of , with maps (source), (target). is the set of specifications, specifies the value at the argument . For , we write for the class and for the notation presumes that .
For each , , and in the class of all arrows an arrows in .
For every , such that is inhabited (non-empty).
hold identity. For all and , we have
hold composition. Whenever , , , and .
See also
Profunctor
Notes
References
Bibliography
Further reading
- Kelly had already noticed a notion that was essentially the same as anafunctor in this paper, but did not seem to develop the notion further.
External links
Axiom of choice
Functors | Anafunctor | [
"Mathematics"
] | 343 | [
"Functions and mappings",
"Mathematical structures",
"Mathematical objects",
"Mathematical axioms",
"Axiom of choice",
"Mathematical relations",
"Functors",
"Axioms of set theory",
"Category theory"
] |
76,916,978 | https://en.wikipedia.org/wiki/Phosphatoantimonate | Phosphatoantimonates are compounds that contain anions that contain phosphorus and antimony in the +5 oxidation state, along with oxygen. Thus they are a compound of phosphate and antimonate, bound together by oxygen.
phosphatoantimonates have been investigated as catalysts, and ion exchange materials.
List
References
Antimonates
Phosphates | Phosphatoantimonate | [
"Chemistry"
] | 77 | [
"Phosphates",
"Salts"
] |
76,918,664 | https://en.wikipedia.org/wiki/Jan-Theodoor%20Janssen | Theodorus Johannes Bernardus Maria Janssen (born 1965), also known as Jan-Theodoor Janssen or JT Janssen, is the Chief Scientist of the National Physical Laboratory (United Kingdom), Henry Royce Institute's Strategic Advisory Board (SAB) Chair since 2024, and President of the Consultative Committee for Ionizing Radiation (CCRI) since 2023. In 2023, he was awarded the Institute of Physics's James Joule Medal and Prize for "outstanding contributions to fundamental and practical quantum electrical metrology". He was elected a Fellow of the National Physical Laboratory in Quantum Electrical Metrology, Fellow of the Institution of Engineering and Technology (IET), Fellow of the Institute of Physics (IOP), and Fellow of the Royal Academy of Engineering in 2021.
Born in the Netherlands, Janssen obtained a doctor of philosophy from the University of Nijmegen in 1993, before joining the University of Bristol as a research fellow and then moving to NPL in 1998. He is a visiting professor at the Lancaster University.
References
External links
Fellows of the National Physical Laboratory (United Kingdom)
Fellows of the Institution of Engineering and Technology
1965 births
Fellows of the Royal Academy of Engineering
Fellows of the Institute of Physics
Living people
Radboud University Nijmegen alumni
People associated with Lancaster University | Jan-Theodoor Janssen | [
"Engineering"
] | 267 | [
"Institution of Engineering and Technology",
"Fellows of the Institution of Engineering and Technology"
] |
76,919,299 | https://en.wikipedia.org/wiki/Exidia%20pithya | Exidia pithya is a species of fungus in the family Auriculariaceae. Basidiocarps (fruit bodies) are gelatinous, black, and button-shaped at first, later coalescing and drying to form tar-like patches. The species grows on dead branches of conifers in continental Europe.
Taxonomy
The species was originally found growing on pine in Germany and was described in 1805 by the German mycologists Johannes Baptista von Albertini and Lewis David de Schweinitz.
Description
Exidia pithya forms grey-black to brown-black, gelatinous fruit bodies that are button-shaped at first, coalescing with age and forming effused patches up to 20 cm long. The upper, spore-bearing surface is normally smooth, becoming slightly furrowed, occasionally with a few scattered pegs or warts. The spore print is white.
Microscopic characters
The microscopic characters are typical of the genus Exidia. The basidia are ellipsoid and septate. The spores are cylindrical to weakly allantoid (sausage-shaped), 11 to 15 by 4 to 5 μm.
Similar species
Fruit bodies of Exidia glandulosa and E. nigricans are similarly coloured, but occur on broad leaved trees. Fruit bodies of E. saccharina and E. umbrinella occur on conifers, but are brown to orange-brown.
Habitat and distribution
Exidia pithya is a wood-rotting species, typically found on dead branches. It was originally described from pine (Pinus species), but is more common on spruce (Picea species) and less common on fir and larch (Abies and Larix species). It is widely distributed throughout continental Europe from Scandinavia to Turkey, but is absent from the British Isles.
References
Auriculariales
Fungi described in 1805
Fungi of Europe
Fungus species
Taxa named by Lewis David de Schweinitz
Taxa named by Johannes Baptista von Albertini | Exidia pithya | [
"Biology"
] | 407 | [
"Fungi",
"Fungus species"
] |
68,090,028 | https://en.wikipedia.org/wiki/Bochner%27s%20tube%20theorem | In mathematics, Bochner's tube theorem (named for Salomon Bochner) shows that every function holomorphic on a tube domain in can be extended to the convex hull of this domain.
Theorem Let be a connected open set. Then every function holomorphic on the tube domain can be extended to a function holomorphic on the convex hull .
A classic reference is (Theorem 9). See also for other proofs.
Generalizations
The generalized version of this theorem was first proved by Kazlow (1979), also proved by Boivin and Dwilewicz (1998) under more less complicated hypothese.
Theorem Let be a connected submanifold of of class-. Then every continuous CR function on the tube domain can be continuously extended to a CR function on . By "Int ch(S)" we will mean the interior taken in the smallest dimensional space which contains "ch(S)".
References
Several complex variables
Theorems in complex analysis | Bochner's tube theorem | [
"Mathematics"
] | 205 | [
"Theorems in mathematical analysis",
"Functions and mappings",
"Several complex variables",
"Theorems in complex analysis",
"Mathematical objects",
"Mathematical relations"
] |
68,090,298 | https://en.wikipedia.org/wiki/Heat%20dome | A heat dome is a weather phenomenon consisting of extreme heat that is caused when the atmosphere traps hot air as if bounded by a lid or cap. Heat domes happen when strong high pressure atmospheric conditions remain stationary for an unusual amount of time, preventing convection and precipitation and keeping hot air "trapped" within a region. This can be caused by multiple factors, including sea surface temperature anomalies and the influence of a La Niña. The upper air weather patterns are slow to move, referred to by meteorologists as an Omega block.
The term is often extrapolated in media terminology for any heat wave situation, though heat waves differ as they are periods of excessively hot weather not necessarily caused by such stationary high-pressure systems. The term heat dome is also used in the context of urban heat islands.
Characteristics
Heat domes are typically associated with minimal cloud cover and clear skies, which allow the unhindered penetration of solar radiation to the Earth's surface, intensifying the overall temperature.
They also cover a large geographical area that has a greater atmospheric pressure than the surrounding regions. The high-atmospheric pressure area acts like a lid on the atmosphere and causes warm air to be pushed to the surface and holding it there over extended durations.
Heat domes allow maximum heating of the Earth as they allow penetration of sunshine to the surface of the Earth.
Creation
Heat domes can arise in still and dry summer conditions, when a mass of warm air builds up, and the high pressure from the Earth's atmosphere pushes the warm air down. The air is then compressed, and as its net heat is now in a smaller volume, it increases in temperature. As the warm air attempts to rise, the high pressure above it acts as a dome, forcing the air down and causing it to get hotter and hotter, resulting in increased pressure below the dome.
The 2021 Northwest heat dome was formed in this way, as a stagnant high-pressure system intensified local temperatures, blocked cooling maritime breezes, and hindered cloud formation. This allowed uninterrupted solar radiation to further warm the air and the rising warm air was pushed back down by the high-pressure system, creating a self-sustaining cycle of heating.
Increases in sea surface temperatures across the Northern Pacific, particularly off the coast of Washington, Oregon, and British Columbia, create favorable conditions for the formation of high atmospheric pressure domes, which can lead to the development of heat domes.
Relationship to climate change
Studies indicate that human-induced climate change plays a significant role in the formation of heat domes, as heat domes are more likely to occur in higher atmospheric temperatures. The occurrence of heat domes contributes to the positive feedback loop of increased climate change by resulting in overall higher atmospheric temperatures.
Effects
Other weather events
Heat domes coincide with stagnant atmospheric conditions, exacerbating air quality issues. Common byproducts include increased smog and pollution levels. Heat domes can intensify heat waves by interacting with other weather systems, such as frontal boundaries. They can also contribute to drought by increasing the rate of evaporation and reducing soil moisture. In areas such as California's Central Valley, heat domes exacerbate drought conditions by increasing the rate of evaporation amongst crops and native vegetation.
Ecosystem
Previous heat domes have been linked to the widespread damage of trees, primarily through high solar irradiation. Alongside foliar scorching as a result of heat stress, the evolutionary creation and success of heat-resilient foliar species were byproducts of heat domes.
Heat domes increase the thermal stress of organisms living in intertidal ecosystems, a factor that has previously led to the deaths of marine species during the 2021 North American Heat Dome.
Community
The occurrence of heat domes has contributed to increasing climate change concerns. This was particularly demonstrated among British Columbians, who in previous studies displayed higher levels of climate change anxiety following the 2021 North American Heat Dome.
Heat domes put communities at risk of increased mortality rates. Deaths resulting from heat domes are more likely to impact susceptible and marginalized populations, who are less likely to have access to air-conditioned living spaces.
Notable events
The 2021 Western North America heat dome garnered its attention for its unprecedented intensity and duration in recent years which led to significant societal influences such as widespread power outages and increased wildfire activities. This further emphasized the urgency of addressing climate change in order to reduce the occurrence and severity of such events. Addressing greenhouse gas emissions and adopting strategies are significant steps in lessening the frequency of extreme heat events in 2021.
In 2021, a record-breaking heat dome based in British Columbia caused 595 community deaths, a record for similar atmospheric events. Most households in the broader Vancouver lack air conditioning, resulting in individuals being highly susceptible to deaths caused by heat such as heat exhaustion and heat stroke. The study on this event emphasizes the importance of public health and providing more air conditioning and urban green spaces.
Persistent heat dome led to extensive wildfires, crop failures, and a surge in mortality rates during the Russian heatwave in 2010. The far-reaching consequences affected by economic and social factors of this event reverberated globally, impacting the interconnectedness of regional weather phenomena and agricultural markets.
Examples
1936 North American heat wave
2012 North American heat wave
2018 North American heat wave
2021 Russia heatwave
2021 British Columbia wildfires
2021 Western North America heat wave
2023 Western North America heat wave
2023 South America heat wave
Future
Research points to a projected increase in stationary waves circulating around North America following the occurrence of heat domes. These are the same waves that lead to extreme heat events, indicating a higher likelihood of similar events taking place in the future. Research studies have shown that the development of heat domes is generally improbable, however the increasing level of concern surrounding the impact of climate change highlights that heat domes may no longer become a rare occurrence.
Mitigation
Techniques to mitigate the effects of heat domes often involve urban planning, public health initiatives, and community interaction. Strategies include increasing green areas, using cool roofs and improving ventilation in urban areas. Public agencies provide support to vulnerable populations, reducing adverse heat-related impacts through the following methods: heat health warning systems, data monitoring, cooling centers, water management, and climate change suppression, among other efforts. Educational campaigns increase awareness of heat safety, increasing the effectiveness of other mitigation methods.
See also
Heat wave
Extreme weather
References
External links
What is a Heat Dome?—Scientific American
BBC reference
sky.com reference
telegraph.co.uk reference
severe-weather.eu/ on heat domes
YouTube reference
Atmospheric dynamics
Meteorological phenomena | Heat dome | [
"Physics",
"Chemistry"
] | 1,329 | [
"Physical phenomena",
"Earth phenomena",
"Atmospheric dynamics",
"Meteorological phenomena",
"Fluid dynamics"
] |
68,090,839 | https://en.wikipedia.org/wiki/Matter%20%28journal%29 | Matter is a peer-reviewed scientific journal that covers the general field of materials science. It is published by Cell Press and the editor-in-chief is Steven W. Cranford.
External links
Academic journals established in 2019
Cell Press academic journals
Monthly journals
English-language journals
Materials science journals | Matter (journal) | [
"Materials_science",
"Engineering"
] | 60 | [
"Materials science stubs",
"Materials science journals",
"Materials science journal stubs",
"Materials science"
] |
68,091,202 | https://en.wikipedia.org/wiki/Chromatin%20variant | A chromatin variant (also known as an epigenetic lesion, epimutation or epigenetic alteration) corresponds to a section of the genome that differs in chromatin states across cell types/states within an individual (intra-individual) or between individuals for a given cell type/state (inter-individual). Chromatin variants distinguish DNA sequences that differ in their function in one cell type/state versus another. Chromatin variants are found across the genome, inclusive of repetitive and non-repetitive DNA sequences. Chromatin variants range in sizes. The smallest chromatin variants cover a few hundred DNA base pairs, such as seen at promoters, enhancers or insulators. The largest chromatin variants capture a few thousand DNA base pairs, such as seen at Large Organized Chromatin Lysine domains (LOCKs) and Clusters Of Cis-Regulatory Elements (COREs), such as super-enhancer.
References
Gene expression
Molecular genetics | Chromatin variant | [
"Chemistry",
"Biology"
] | 199 | [
"Gene expression",
"Molecular genetics",
"Cellular processes",
"Molecular biology",
"Biochemistry"
] |
68,092,222 | https://en.wikipedia.org/wiki/Institute%20for%20Safe%20Medication%20Practices | The Institute for Safe Medication Practices (ISMP) is an American 501(c)(3) organization focusing on the prevention of medication errors and promoting safe medication practices. It is affiliated with ECRI.
Activities
Among others, ISMP maintains and disseminates a list of "do not crush" medications, as well as clinical best practices. The ISMP's Medication Safety Self-Assessment tool has been used in surveys of medication safety in hospitals in the United States and elsewhere.
The ISMP frequently investigates and reports on medication errors that have occurred in practice. These investigations are often published in the peer-reviewed journal Hospital Pharmacy.
References
Pharmacology
Drug safety
Patient safety | Institute for Safe Medication Practices | [
"Chemistry"
] | 139 | [
"Pharmacology",
"Drug safety",
"Medicinal chemistry stubs",
"Medicinal chemistry",
"Pharmacology stubs"
] |
68,093,286 | https://en.wikipedia.org/wiki/Zimcelebs | Zimcelebs is a Zimbabwean celebrity news social media-based blog.
Background
Zimcelebs was founded in February 2017 as Zimcelebs TV by Lewis John. John was running a nightclub in South Africa then and he engaged Tafadzwa Gondo who was a freelance journalist to become a partner, the duo revealed that the Zimcelebs idea was inspired by The Shade Room. Over the years, the platform has become one of Zimbabwe's portals for celebrity breaking news and the social media based blog has accumulated a significant following. In March 2021, Zimcelebs was listed as the 6th most influential social media platform in Zimbabwe with the highest engagement percentage and has about 7 million views on YouTube.
Since 2019, Zimcelebs has launched a number of online programmes where musical artists go for live performances which are Ndipe Mic 2019, Bhazi reMangoma 2020, Garage Sessions 2021 and MaChillz. These sessions have hosted top artists like Alick Macheso, Enzo Ishall, Tocky Vibes, Poptain, Stunner, Jah Signal, Winky D, Mudiwa Hood, Kikky Badass, Seh Calaz, Nutty O, Bazooker, Holy Ten, Baba Harare. In 2020, Passion Java Records launched Garamumba which was the first Zimbabwean lockdown online performances session, and it was launched and streamed on Zimcelebs social media from part one to part seven. The segments averaged 300,000 to 500,000 views per session.
Recognition
Zim Glam Awards 2018 – Best Online Media
Changamire Festival Awards 2019 – Best Online Media
Zimdancehall Awards 2019 – Best Online Media
National Arts Merit Awards 2020 – Outstanding Online Media nomination
Zimbabwe Achievers Awards 2020 – Simba Mhere category for best online platform winner 2020
Changamire Festival Awards 2021 – Best Brand Supporting Hip Hop
References
Social media
Celebrity fandom | Zimcelebs | [
"Technology"
] | 403 | [
"Computing and society",
"Social media"
] |
68,093,322 | https://en.wikipedia.org/wiki/GCB%20Bioenergy | GCB Bioenergy: Bioproducts for a Sustainable Bioeconomy is a monthly peer-reviewed scientific journal covering research on the interface between biological systems and the production of bioenergy, biofuels and bioproducts directly from plants, algae and waste. The editor-in-chief is Stephen P. Long, environmental plant physiologist, Fellow of the Royal Society and member of the National Academy of Sciences (University of Illinois and Lancaster University).
This journal is a sister journal to Global Change Biology.
External links
References
Wiley-Blackwell academic journals
Bioenergy | GCB Bioenergy | [
"Environmental_science"
] | 122 | [
"Environmental science journals",
"Environmental science journal stubs"
] |
68,097,758 | https://en.wikipedia.org/wiki/HD%20176693 | HD 176693, also known as Kepler-408, is a star with a close orbiting exoplanet in the northern constellation of Draco. It is located at a distance of 291 light years from the Sun based on parallax measurements, but it is drifting closer with a radial velocity of −55 km/s. The star is predicted to come as close as in 1.6 million years. It has an apparent visual magnitude of 8.83, which is too faint to be viewed with the naked eye.
The spectrum of HD 176693 matches an F-type main-sequence star with a stellar classification of F8V. The star is older than the Sun, at . It is slightly and uniformly depleted in heavy elements compared to the Sun, having about 75% of the solar abundance of iron and other heavy elements. HD 176693 is a chromospherically inactive star, although there is weak evidence for tidal spin-up due to star-planet interaction.
HD 176693 is 5% more massive than the Sun and has a 25% larger radius. It is radiating 1.9 times the luminosity of the Sun from its photosphere at an effective temperature of 6,080 K. The star is spinning with a rotation period of 12.89 days. As of 2016, multiplicity surveys have not detect any stellar companions to HD 176693.
Planetary system
In 2014, a transiting Sub-Earth planet b was detected on a tight 2.5 day orbit. Initially reported with a relatively low confidence of 97.9%, it was confirmed in 2016.
The planetary orbit is inclined to the equatorial plane of the star by 41.7°. Such strong spin-orbit misalignment is unique for a sub-Earth transiting planet, and needs either additional giant planets in the system or a history of close stellar encounters to explain it. The planet may also be a captured body originating from elsewhere.
References
F-type main-sequence stars
Planetary systems with one confirmed planet
Planetary transit variables
Draco (constellation)
BD+48 2806
1612
J18590868+4825236
176693 | HD 176693 | [
"Astronomy"
] | 443 | [
"Constellations",
"Draco (constellation)"
] |
68,098,850 | https://en.wikipedia.org/wiki/Nomadic%20conflict | Nomadic conflict, also called farmer–herder conflict, is a type of environmental conflict where farming and herding communities overlap and has been used to refer to fighting among herding communities or fighting between herding and farming communities. This is sometimes referred to as conflict involving “pastoralists” or “nomadic” people and “agriculturalists” or “settled” people. The conflicts usually arise from destruction of crops by livestock and is exacerbated during times when water and lands to graze are scarce.
Background
There are several hundred million pastoralists worldwide and Africa contains about 268 million pastoralists, over a quarter of its population, who live on about 43 percent of the continent’s land mass.
Commercial displacement
Displacement of local communities to make way for commercial farms or mining activities has put pressure on grazing areas, exacerbating conflict.
Climate change and land degradation
Desertification in the Sahel, where much of the present-day conflicts between herders and farmers takes place, is expanding southward by about 1400 square miles a year. Climate change has apparently exacerbated land degradation, which leads to more competition over grazing areas.
History
Malti Malik summarises relationships and inter-dependencies between sheep-herders and sedentary farmers in Mari, a city-state on the Euphrates (in present-day Syria) which flourished between 2900 and 1759 BCE. The "nomadic groups included the Akkadians, Amorites, Assyrians and Aramaeans. [...] Some of them gained much power and succeeded in establishing their own rule. For example, the kings of Mari were Amorites." Interactions included trade and employment (as harvest workers or hired soldiers) as well as "robbing and plundering".
Similarly, in the 13th century CE nomadic Mongols subjugated many of the agriculture-based states of Eurasia and founded the Mongol Empire.
Examples
Cameroon
More than 30,000 people in northern Cameroon fled to Chad after ethnic clashes over access to water between Musgum fishermen and ethnic Arab Choa herders in December 2021.
Central African Republic
In the Central African Republic Civil War, a large portion of the fighting was between rebel groups known as ex-Séléka and rebel groups known as anti-balaka. While the ex-Séléka consisted of those who were largely Muslim and the anti-balaka consisted of those who were largely Christian and animist, an added dimension of the conflict was that ex-Séléka consisted of those from nomadic groups, such as the Fulani, Gula and Runga, and the anti-balaka consisted of those from agriculturalist groups.
Congo, Democratic Republic of
Ethnic conflict in Kivu has often involved the Congolese Tutsis known as Banyamulenge, a cattle herding group that largely migrated from Rwanda in the 19th century and are often derided as outsiders. They are pitted against other ethnic groups who consider themselves indigenous. Militias drawn from the Bembe, Bafuliru and Banyindu have attacked and stolen cattle from the Banyamulenge.
Kenya
Nigeria
Sudan and South Sudan
Nomadic conflict in Sudan has been a part of the Second Sudanese Civil War, the War in Darfur and the Sudanese conflict in South Kordofan and Blue Nile and has been a feature in ethnic violence in South Sudan.
References
Nomads
Social conflict
Environmental sociology | Nomadic conflict | [
"Environmental_science"
] | 684 | [
"Environmental sociology",
"Environmental social science"
] |
68,102,162 | https://en.wikipedia.org/wiki/Malgrange%E2%80%93Zerner%20theorem | In mathematics, Malgrange–Zerner theorem (named for Bernard Malgrange and Martin Zerner) shows that a function on allowing holomorphic extension in each variable separately can be extended, under certain conditions, to a function holomorphic in all variables jointly. This theorem can be seen as a generalization of Bochner's tube theorem to functions defined on tube-like domains whose base is not an open set.
Theorem Let
and let convex hull of . Let be a locally bounded function such that and that for any fixed point the function is holomorphic in in the interior of for each . Then the function can be uniquely extended to a function holomorphic in the interior of .
History
According to Henry Epstein, this theorem was proved first by Malgrange in 1961 (unpublished), then by Zerner (as cited in ), and communicated to him privately. Epstein's lectures contain the first published proof (attributed there to Broz, Epstein and Glaser). The assumption was later relaxed to (see Ref.[1] in ) and finally to .
References
Several complex variables | Malgrange–Zerner theorem | [
"Mathematics"
] | 230 | [
"Theorems in mathematical analysis",
"Functions and mappings",
"Several complex variables",
"Theorems in complex analysis",
"Mathematical objects",
"Mathematical relations"
] |
68,103,177 | https://en.wikipedia.org/wiki/Arturo%20Campos | Arturo Campos (1934 – September 5, 2001) was an American electrical engineer who worked at NASA on the electrical systems for the Apollo and Space Shuttle programs. He played a major role in devising a solution to the emergency that arose during the Apollo 13 mission.
Early life and education
Campos was born into a Mexican American family in Laredo, Texas; his father was a mechanic. He graduated in 1952 from Martin High School, attended Laredo Junior College, and in 1956 earned a degree in electrical engineering from the University of Texas.
Career
He worked at Kelly Air Force Base as an aircraft maintenance supervisor before joining NASA in September 1963. At the Johnson Space Center, he played a major role in developing the electrical systems for both the Apollo spacecraft and the Space Shuttle. On April 13, 1970, he was the subsystem manager responsible for the lunar module power system when the Apollo 13 mission suffered a loss of power due to a fuel cell explosion, and led the way in devising a solution so that the three astronauts aboard could return to Earth safely. He retired from NASA in 1980 and became a consultant in electrical engineering in Houston.
While at the Johnson Space Center, Campos established its branch of the League of United Latin American Citizens and in 1974 became its first president, was a member of the employees' Hispanic Heritage Program, and served as Equal Employment Opportunity and Affirmative Action Program representative.
Personal life and death
Campos and his wife, Petra T. Campos, had three daughters. He died of a heart attack at his home in Seabrook, Texas, at 66.
Honors and legacy
Campos shared in the Presidential Medal of Freedom that was awarded to the Mission Control staff after the Apollo 13 incident.
He was inducted into the Martin High School Hall of Fame in 2002.
After a public contest, his name was used for the male mannequin Commander Moonikin Campos to be used to test radiation exposure and other hazards on the Artemis 1 lunar mission in 2022.
References
1934 births
2001 deaths
American electrical engineers
University of Texas alumni
Martin High School (Laredo, Texas) alumni
People from Laredo, Texas
Apollo 13
Artemis program
American people of Mexican descent
NASA people | Arturo Campos | [
"Astronomy"
] | 433 | [
"Outer space stubs",
"Outer space",
"Astronomy stubs"
] |
68,103,938 | https://en.wikipedia.org/wiki/Aristotelian%20realist%20philosophy%20of%20mathematics | In the philosophy of mathematics, Aristotelian realism holds that mathematics studies properties such as symmetry, continuity and order that can be immanently realized in the physical world (or in any other world there might be). It contrasts with Platonism in holding that the objects of mathematics, such as numbers, do not exist in an "abstract" world but can be physically realized. It contrasts with nominalism, fictionalism, and logicism in holding that mathematics is not about mere names or methods of inference or calculation but about certain real aspects of the world.
Aristotelian realists emphasize applied mathematics, especially mathematical modeling, rather than pure mathematics as philosophically most important. argues that "Aristotelian realism allows mathematical facts to be explainers in distinctively mathematical explanations" in science as mathematical facts are themselves about the physical world. Paul Thagard describes Aristotelian realism as "the current philosophy of mathematics that fits best with what is known about minds and science."
History
Although Aristotle did not write extensively on the philosophy of mathematics, his various remarks on the topic exhibit a coherent view of the subject as being both about abstractions and applicable to the real world of space and counting.
Until the eighteenth century, the most common philosophy of mathematics was the Aristotelian view that it is the "science of quantity", with quantity divided into the continuous (studied by geometry) and the discrete (studied by arithmetic).
Aristotelian approaches to the philosophy of mathematics were rare in the twentieth century but were revived by Penelope Maddy in Realism in Mathematics (1990) and by a number of authors since 2000 such as James Franklin, Anne Newstead, Donald Gillies, and others.
Numbers and sets
Aristotelian views of (cardinal or counting) numbers begin with Aristotle's observation that the number of a heap or collection is relative to the unit or measure chosen: "'number' means a measured plurality and a plurality of measures ... the measure must always be some identical thing predicable of all the things it measures, e.g. if the things are horses, the measure is 'horse'." Glenn Kessler develops this into the view that a number is a relation between a heap and a universal that divides it into units; for example, the number 4 is realized in the relation between a heap of parrots and the universal "being a parrot" that divides the heap into so many parrots.
On an Aristotelian view, ratios are not closely connected to cardinal numbers. They are relations between quantities such as heights. A ratio of two heights may be the same as the relation between two masses or two time intervals.
Aristotelians regard sets as well as numbers as instantiated in the physical world (rather than being Platonist entities). Maddy argued that when an egg carton is opened, a set of three eggs is perceived (that is, a mathematical entity realized in the physical world). However not all mathematical discourse needs to be interpreted realistically; for example Aristotelians may regard the empty set and zero as fictions, and possibly higher infinities.
Structural properties
Aristotelians regard non-numerical structural properties like symmetry, continuity and order as equally important as numbers. Such properties are realized in physical reality, and are the subject matter of parts of mathematics. For example group theory classifies the different kinds of symmetry, while the calculus studies continuous variation. Provable results about such structures can apply directly to physical reality. For example Euler proved that it was impossible to walk once and once only over the seven bridges of Königsberg.
Epistemology
Since mathematical properties are realized in the physical world, they can be directly perceived. For example, humans easily perceive facial symmetry.
Aristotelians also accord a role to abstraction and idealisation in mathematical thinking. This view goes back to Aristotle's statement in his Physics that the mind 'separates out' in thought the properties that it studies in mathematics, considering the timeless properties of bodies apart from the world of change (Physics II.2.193b31-35).
At the higher levels of mathematics, Aristotelians follow the theory of Aristotle's Posterior Analytics, according to which the proof of a mathematical proposition ideally allows the reader to understand why the proposition must be true.
Objections to Aristotelian realism
A problem for Aristotelian realism is what account to give of higher infinities, which may not be realized or realizable in the physical world. Mark Balaguer writes:
"Set theory is committed to the existence of infinite sets that are so huge that they simply dwarf garden variety infinite sets, like the set of all the natural numbers. There is just no plausible way to interpret this talk of gigantic infinite sets as being about physical objects."
Aristotelians reply that sciences can deal with uninstantiated universals; for example the science of color can deal with a shade of blue that happens not to occur on any real object. However that does require denying the instantiation principle, held by most Aristotelians, which holds that all genuine properties are instantiated. One Aristotelian philosopher of mathematics who denies the instantiation principle on the basis of Frege’s distinction between sense and reference is Donald Gillies. He has used this approach to develop a method of dealing with very large transfinite cardinals from an Aristotelian point of view.
Another objection to Aristotelianism is that mathematics deals with idealizations of the physical world, not with the physical world itself. Aristotle himself was aware of the argument that geometers study perfect circles but hoops in the real world are not perfect circles, so it seems that mathematics must be studying some non-physical (Platonic) world. Aristotelians reply that applied mathematics studies approximations rather than idealizations and that as a result modern mathematics can study the complex shapes and other mathematical structures of real things.
References
Bibliography
John Bigelow, 1988, The Reality of Numbers, Clarendon, Oxford,
James Franklin, 2014, An Aristotelian Realist Philosophy of Mathematics: Mathematics as the Science of Quantity and Structure, Palgrave Macmillan, Basingstoke, .
Keith Hossack, 2020, Knowledge and the Philosophy of Number: What Numbers Are and How They Are Known, Bloomsbury, London,
Andrew Irvine, 1990. Physicalism in Mathematics, Dordrecht, London,
Bob Knapp, 2014, Mathematics is About the World, Lexington KY,
Penelope Maddy, 1990, Realism in Mathematics, Oxford University Press, New York,
Woosuk Park, 2018, Philosophy's Loss of Logic to Mathematics, Springer, Cham,
Andrew Younan, 2022, Matter and Mathematics: An Essentialist Account of Laws of Nature, Catholic University of America Press, Washington DC,
External links
The Sydney School in the philosophy of mathematics
Philpapers category Mathematical Aristotelianism
Philosophy of mathematics
Aristotelianism | Aristotelian realist philosophy of mathematics | [
"Mathematics"
] | 1,418 | [
"nan"
] |
68,104,017 | https://en.wikipedia.org/wiki/David%20Schrooten | David Benjamin Schrooten is a Dutch computer hacker also known as Fortezza and Xakep. In 2012, he was arrested in Romania at the request of the United States Secret Service and extradited to Seattle, Washington. Here he was sentenced to 12 years in federal prison, primarily for his role in trafficking credit cards he obtained by hacking other hackers. By doing so, he caused approximately 63 million dollars in damages.
In 2014 he was sent back to the Netherlands through a treaty transfer and subsequently released in December that same year. After his release he authored a book named Alias Fortezza chronicling his arrest and incarceration.
As a computer hacker he was particularly notorious for hacking rival groups such as the Infraud Organization, in which he crowned himself admin under the alias xakep. He was also known as one of the founders of the cybercrime forum kurupt. That later split up in two separate forums, because of infighting among founding members. The break up resulted in hacking skirmishes between the groups that ended when they started publishing each other names. After his arrest, the remaining forum kurupt.ru kept operating and continued getting themselves involved in high profile hacking endeavours such as the stophaus attack, that broke a part of the internet.
References
Dutch computer specialists
Hackers
21st-century Dutch criminals
People extradited from the Netherlands
People extradited to the United States
Foreign nationals imprisoned in the United States
Year of birth missing (living people)
Living people | David Schrooten | [
"Technology"
] | 305 | [
"Lists of people in STEM fields",
"Hackers"
] |
68,105,840 | https://en.wikipedia.org/wiki/Nitro-Mannich%20reaction | The nitro-Mannich reaction (or aza-Henry reaction) is the nucleophilic addition of a nitroalkane (or the corresponding nitronate anion) to an imine, resulting in the formation of a beta-nitroamine. With the reaction involving the addition of an acidic carbon nucleophile to a carbon-heteroatom double bond, the nitro-Mannich reaction is related to some of the most fundamental carbon-carbon bond forming reactions in organic chemistry, including the aldol reaction, Henry reaction (nitro-aldol reaction) and Mannich reaction.
Although extensive research has been conducted into the aforementioned reactions, the nitro-Mannich reaction has been studied to a far lesser extent even though it has been known for well over 100 years. Significant attention only started to develop after the report of Anderson and co-workers at the turn of the century, and has since resulted in a wide range of novel methodologies. The interest into the nitro-Mannich reaction stems from the synthetic utility of the beta-nitroamine products. They can be further manipulated by various methods, including reductive removal of the nitro group allowing access to monoamines, reduction of the nitro group affords 1,2-diamines and conversion of the nitro group into a carbonyl functionality furnishes beta-aminocarbonyl compounds.
History
Early Examples of the Nitro-Mannich Reaction
The first nitro-Mannich reaction was reported by Henry in 1896. In this report, Henry described the addition of nitroalkanes to an imine derived from hemiaminal. Elimination of water forms in-situ an imine, which then reacts with the nitro group (as a nitronate ion) to form a beta-nitroamine that can subsequently react further forming one of the two adducts. Although this is the first report of the nitro-Mannich reaction, no yields of the products were given.
After Henry’s seminal report, Mousset and Duden made contributions to the field by studying the addition of branched nitroalkanes to hemiaminals using the same procedures reported by Henry. An example of nitro group reduction to an amine using SnCl2 and HCl was also disclosed by Duden and co-workers, thus representing the first use of the nitro-Mannich reaction to prepare polyamines. The next report did not appear until 1931, when Cerf de Mauny conducted a thorough study of Henry’s original work using hemiaminals. The scope of the reaction was extended to higher order nitroalkanes affording a beta-nitroamine in excellent yields.
The next contributions appeared in 1946, when Senkus and Johnson independently reported their studies into the nitro-Mannich reaction. Senkus and co-workers illustrated that nitroalkanes may react with methanal (formaldehyde) and substituted primary amines in the presence of sodium sulfate (Na2SO4) to afford a variety of substituted beta-nitroamines in moderate to good yields. When using primary nitroalkane substrates, double addition of the nitroalkane to the imine was observed, but this could be avoided by employing secondary nitroalkanes. The study reported by Johnson and co-workers also employed formaldehyde, but this was used in conjunction with a selection of secondary amines, furnishing the corresponding beta-nitroamines in moderate to good yields. Both authors also reduced the nitro group to an amine functionality using Raney Nickel.
Up until this point, all of the nitro-Mannich methodologies reported had used imines that were formed in situ from an aldehyde and an amine. In 1950, Hurd and Strong reported the first nitro-Mannich reaction using a preformed imine. Exposing an imine to a nitroalkane afforded a substituted beta-nitroamines in moderate yields. The moderate yields obtained when using the preformed imine could possibly be attributed to a competing decomposition pathway of the imine or the product.
These early nitro-Mannich methodologies have been used by a number of groups for the synthesis of a variety of heterocyclic products, conjugated nitroalkenes (via elimination of the amino group) and dinitroamines.
Non-Enantioselective Nitro-Mannich Reactions
Although the nitro-Mannich reaction enables access to synthetically useful beta-nitroamine motifs, the lack of selectivity in their synthesis remained a significant problem. Interest in the field started to increase considerably after Anderson and co-workers reported the first diastereoselective acyclic nitro-Mannich reaction. A nitroalkane and n-butyllithium (nBuLi) were combined at -78 °C to give the corresponding nitronate ions. A selection of N-PMB imines were then added to the reaction mixture and after quenching with acetic acid, the beta-nitroamine products were afforded in good yields with moderate to good diastereoselectivities.
The authors then converted the beta-nitroamines into unprotected 1,2-diamines via a two step procedure. Firstly, the nitro group was reduced to amines using samarium iodide, followed by PMB removal in the presence of ceric ammonium nitrate (CAN). The same group later reported improvements to this methodology and expanded these preliminary results in further publications.
In 2000, Anderson and co-workers reported the racemic nitro-Mannich reaction of TMS-protected nitronate with N-PMB or N-PMP imines catalysed by Sc(OTf)3. The authors first attempted the nitro-Mannich reaction using lithium-nitronates, however no product was formed using these conditions. As a result, the TMS-protected nitronate was used in conjunction with Scandium(III) trifluoromethanesulfonate [Sc(OTf)3] (4 mol%) to afford the beta-nitroamine products in moderate to excellent yields for a range of alkyl and aryl N-PMB and N-PMP protected imines.
Following Anderson’s report, Qian and co-workers described the Ytterbium(III) trifluoromethanesulfonate [Yb(OiPr)3] catalysed nitro-Mannich reaction of N-sulfonyl imines and nitromethane. Using mild reactions conditions, the β-nitroamines bearing electron-rich and electron-poor aryl substituents were furnished in excellent yields after short reaction times.
Direct Metal Catalysed Enantioselective Nitro-Mannich Reactions
The first enantioselective metal catalysed nitro-Mannich reaction was reported by Shibasaki and co-workers in 1999. The authors used a binaphthol ligated Yb/K heterobimetallic complex to induce enantiocontrol in the reaction, furnishing β-nitroamines in moderate to good yields with good enantioselectivities. However, nitromethane was the only nitroalkane that could be used with the heterobimetallic complex and the reactions were very slow (2.5–7 days) even when using a relatively high catalyst loading of 20 mol%.
Building on the work of Shibasaki, Jørgensen and co-workers reported the asymmetric nitro-Mannich reaction of nitroalkanes and a N-PMP-α-iminoesters. Catalysed by Cu(II)-BOX 52 and triethylamine (Et3N), the reaction afforded β-nitro-α-aminoesters in good yields with excellent enantiocontrol (up to 99% ee). The reaction tolerates a selection of nitroalkanes but is limited exclusively to N-PMP-α-iminoesters. The authors propose that the reaction proceeds via the chair-like transition structure, where both the N-PMP-α-iminoester and the nitronate anion bind to the Cu(II)-BOX complex.
In 2007, Feng and co-workers reported that CuOTf used in conjunction with the shown chiral N-oxide ligand and DIPEA is an efficient catalytic system for the enantioselective nitro-Mannich reaction of nitromethane with N-sulfonyl imines. Combining all of the reagents in THF at –40 °C resulted in the formation of β-nitroamines in excellent yields (up to 99%) and good enantioselectivities for a variety of substituted aryls groups. The postulated intermediate complex is similar to the transition structure proposed by Jørgensen and co-workers, where the ligated copper species binds to the N-sulfonyl imine. A hydrogen bonding interaction is proposed to exist between the amide NH and the nitronate species.
Around the same time as the report of Feng, Shibasaki and co-workers reported one of the most successful enantioselective nitro-Mannich reactions, catalysed by the shown Cu/Sm heterobimetallic complex. Combining N-Boc protected imines and nitroalkanes resulted in moderate to excellent yields and good to excellent enantioselectivities of the products. Interestingly, the nitro-Mannich reaction catalysed by complex affords syn-β-nitroamines, whereas most other enantioselective methodologies favour anti-β-nitroamines. The authors later reported an improved version of the protocol and proposed a mechanistic rational to account for the observed syn diastereoselectivity.
Organocatalysed Enantioselective Nitro-Mannich Reactions
Since the inception of organocatalysis, numerous accounts of organocatalysed enantioselective nitro-Mannich reactions have been reported. These include examples using Brønsted base catalysts, Brønsted acid catalysts, bifunctional Brønsted base/H-bond donor catalysts and phase-transfer catalysts.
Bifunctional Brønsted Base/H-Bond Donor Organocatalysis
Small chiral molecule H-bond donors can be used as a powerful tool for enantioselective synthesis. These low molecular weight entities containing structural frameworks with distinct H-bond donor motifs can catalyse a wide range of carbon-carbon and carbon-heteroatom bond-forming reactions, occurring via H-bond donor activation of the reaction partners as well as through organisation of their spatial arrangement. This area of organic chemistry received limited attention until the seminal work of Jacobsen and Sigman in which they reported a highly enantioselective Strecker reaction using a H-bond donor organocatalyst:
Building on the work of Jacobsen, it was recognised that H-bond donor motifs can be linked via a chiral scaffold to Brønsted basic moieties, creating a new class of bifunctional organocatalysts (see concept figure below). The incorporation of these two functionalities allows the simultaneous activation of the nucleophile (via deprotonation by the Brønsted base) and electrophile (via H-bond donation), thus allowing the development of novel enantioselective reactions through new activation modes.
Based on this concept, Takemoto and co-workers reported the first bifunctional Brønsted base/H-bond donor thiourea organocatalyst 62 (see below) in 2003. This organocatalyst, based on the 1,2-trans-cyclohexanediamine scaffold, imparts high levels of enantiocontrol in the Michael addition of dimethylmalonate to a variety of nitrostyrenes. After this seminal report, numerous other bifunctional organocatalysts were developed derived from the readily available cinchona alkaloid scaffold. The quinidine-derived bifunctional organocatalyst 63 (first reported by Deng and co-workers) acts as a proficient catalyst for Michael addition reactions. In this organocatalytic system, the H-bonding interaction arising from the quinoline alcohol is thought to be crucial for achieving high enantioselectivities.
Also the bifunctional thioureas 64 and 65, again derived from the cinchona alkaloids, are very effective catalysts in Michael addition reactions. The bifunctional thiourea 66 is able to impart high levels of enantiocontrol in the nitro-aldol (Henry) reaction. Bifunctional thiourea 66 differs structurally from bifunctional thioureas 64 and 65, as the thiourea moiety is attached to the quinoline ring of the cinchona scaffold instead of the central stereocentre. Also numerous other bifunctional organocatalyst systems are described, which further expand the range of reactions that can be conducted using bifunctional (thio)urea organocatalysis.
References
Carbon-carbon bond forming reactions
Multiple component reactions
Name reactions | Nitro-Mannich reaction | [
"Chemistry"
] | 2,833 | [
"Name reactions",
"Carbon-carbon bond forming reactions",
"Organic reactions"
] |
68,109,028 | https://en.wikipedia.org/wiki/Sakigake%20%28drug%20designation%29 | Sakigake (さきがけ, lit. "pathfinder", "harbinger") is a drug designation by the Pharmaceuticals and Medical Devices Agency, the pharmaceuticals regulator of Japan. It was designed to provide easier access to novel advanced treatments. It is analogous to the Regenerative Medicine Advanced Therapy designation in the United States and the Advanced Therapy Medicinal Product designation in the European Union.
History
The Sakigake designation was first announced as a pilot by the Ministry of Health, Labour and Welfare on 17 June 2014. The designation system is part of a wider strategy, also named Sakigake, to promote R&D and improve access to new pharmaceuticals. The Pharmaceutical & Medical Device Act Amendments of 2019, which entered into force on 1 September 2020, made the Sakigake designation system a permanent fixture. While application for the Sakigake designation was only open for a short period every year, the permanent Sakigake regime is open year-round.
Effect
The Sakigake designation opens up the possibility for sponsors to seek pre-application consultations, which provide clients with a fixed-price multi-track review of their application.
Statistics
, 24 drugs received Sakigake designation, but only 8 of these (33.33%) were approved.
References
Pharmaceuticals policy
Regulation | Sakigake (drug designation) | [
"Chemistry"
] | 268 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
68,109,605 | https://en.wikipedia.org/wiki/Secondary%20amino%20acid | In organic chemistry, secondary amino acids are amino acids which do not contain the amino group but is rather a secondary amine (). Secondary amino acids can be classified to cyclic acids, such as proline, and acyclic N-substituted amino acids.
In nature, proline, hydroxyproline, pipecolic acid and sarcosine are well-known secondary amino acids. Proline is the only proteinogenic secondary amino acids. Other secondary amino acids are non-proteinogenic amino acids. In protein, hydroxyproline is incorporated into protein by hydroxylation of proline. Pipecolic acid, a heavier analog of proline, is found in efrapeptin. Sarcosine is a N-methylized glycine so its methyl group is used in many biochemical reactions. Azetidine-2-carboxylic acid, which is a smaller homolog of proline in plants.
Properties
Proline and its higher homolog pipecolic acid affect the secondary structure of protein. D-alpha-amino acid - L-alpha-amino acid sequence can induce beta hairpin. It suggested that acyclic secondary amino acids are more flexible than cyclic secondary amino acids in protein by replacement of pipecolic acid by N-methyl-L-alanine in efrapeptin C.
Ninhydrin tests of proline and hydroxyproline give yellow results.
In enzymology, a N-methyl-L-amino-acid oxidase is an oxidase of a subtype of secondary amino acids.
See also
Imino acid
Imidic acid
Secondary amine
References
External links
Amino acids | Secondary amino acid | [
"Chemistry"
] | 342 | [
"Amino acids",
"Biomolecules by chemical classification"
] |
68,109,617 | https://en.wikipedia.org/wiki/Australian%20Society%20for%20Biochemistry%20and%20Molecular%20Biology | The Australian Society for Biochemistry and Molecular Biology (ASBMB) is an academic society founded in 1955. Originally named Australian Biochemical Society, it was renamed to its current title in 1990. Its main activities include hosting scientific conferences, supporting ancillary symposia, workshops and publishing an educational magazine.
History
Biochemical research in Australia began in the 1920s in the Australian national science agency Council for Scientific and Industrial Research (now the CSIRO). The first university biochemistry department then started at the University of Adelaide under Thorburn Brailsford Robertson. There was initially a joint biochemistry and physiology section within the Australian and New Zealand Association for the Advancement of Science.
The society began in 1955 as the Australian Biochemical Society, with Rudi Lemberg as its founding president. It was based on Lemberg's experience with the British Biochemical Society and Hugh Ennor's meetings with the International Union of Biochemistry and relevant university department heads in Australia. Additional key initial members included Frederick Collins as treasurer and Victor Trikojus in a recruitment role.
Meetings and activities
ASBMB has hosted a yearly meeting each year since 1956. It has also coordinated the joint ComBio meeting with societies in related research fields since 1999. It also supports smaller special interest group meetings, symposia, workshops, conferences, and school science competitions.
Publications
The society publishes the magazine Australian Biochemist with three issues per year. The publication started in 1998, following on from the ABS/ASBMB newsletter, which was started in 1970.
Awards
ASBMB gives out an array of annual awards in different categories.
Lemberg Medal - after 5 years' membership for significant contribution
Shimadzu Research Medal - within 15 years post-PhD graduation
Eppendorf Edman ECR Award - within 7 years post-PhD
SDR Scientific Education Award - education (especially innovation and creativity)
Boomerang Award - for expatriate Australians to return to present at the ASBMB conference and seminars at universities/institutes.
The society also awards fellowships to researchers within 2 years post-PhD.
References
Biochemistry organizations
Learned societies of Australia
Scientific organizations established in 1955
Molecular biology organizations | Australian Society for Biochemistry and Molecular Biology | [
"Chemistry",
"Biology"
] | 433 | [
"Biochemistry",
"Biochemistry organizations",
"Molecular biology organizations",
"Molecular biology"
] |
78,250,922 | https://en.wikipedia.org/wiki/%CE%91-Myrcene | α-Myrcene is a monoterpene that is an uncommon isomer of β-myrcene. It has been found in the essential oils of a few species, such as the Balkan Pine and lemongrass.
It differs from the β isomer by the position of one of the three alkene units. The two chemicals can be synthesized in a 3:1 α:β isomeric ratio by pyrolysis of the acetate ester of myrcenol.
References
Polyenes
Monoterpenes | Α-Myrcene | [
"Chemistry"
] | 109 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
78,251,150 | https://en.wikipedia.org/wiki/Solaris%20%28fictional%20planet%29 | Solaris is a fictional living planet depicted in the 1961 science fiction novel Solaris by Polish writer Stanisław Lem and subsequent adaptations into numerous other forms of media. An extraterrestrial life form consisting of a vast, seven hundred billion ton "colloidal envelope" stretching across the entire planet, it regularly forms numerous transient structures on its surface, such as continent-wide crystalline "symmetriads" that dissipate just as quickly as they form, which have been cataloged by scientists on the orbiting Prometheus. Coming to believe it is sentient, they have attempted to study it for over 100 years, creating the scientific discipline of Solaristics. However, their attempts to establish first contact are met with nothing, and the scientists, assuming that it surely would want to communicate with them if it was able to, begin to claim the planet is unintelligent and dying in response to its lack of interest in their advances. Solaris begins creating duplicates of people from the crew's memories known as Phi-creatures in response to an X-ray bombardment, forcing them to reckon with their psychological trauma, though whether Solaris itself understands the import of these beings is uncertain. The protagonist, Dr. Kris Kelvin, eventually sheds his anthropocentric values and visits the planet's surface to establish true contact, realizing Solaris' nature and deciding to remain on the planet to continue studying it.
The planet Solaris was depicted in differing ways in the novel's film adaptations. While appearing as a mysterious, unexplained spatial phenomenon in the 2002 film adaptation, Lem clarified that the original Solaris was intended as a physical form of extraterrestrial life. Despite often being referred to as an ocean, including within the novel itself, Solaris is not aquatic in nature and is more akin to a chemical soup. The depiction of Solaris was praised by critics as a rare example of non-anthropomorphic alien contact in fiction - a creature that does not act, or even think in a way that humans can understand.
Reception
In Worlds Apart, Carl D. Malmgren calls Solaris "one of the strangest novums that Lem has created and 'investigated'." Saying that "there should be no real debate" that Solaris is in fact sentient, he describes it as "Otherness on a grand scale". Calling it "unfathomable" with "invariably strange 'behavior'", he cites Mark Rose as calling it "the most radical [...] late treatment of the alien-contact theme". Describing it as "an alien encounter in the most extreme form", he explains that even more than Solaris itself, the story is focused on Solaristics and the limits of human scientific cognition.
Despite clarifying that Solaris is not technically an ocean, he calls the term an "appropriate and suggestive" name given humans' tendency to anthropomorphize the ocean on Earth despite its otherness. The scientists' observations on the planet are colored by subjectivity, and are often conflicting. At various points in the novel, the Phi-creatures are called a malicious form of torture, an accidental creation, or a purposeful gift to fulfill the crew's desires. In the end, Kelvin is only able to achieve contact when he becomes a blank slate.
Sad Planets describes Solaris as an "enigma", calling some of the book's most moving passages those that describe the planet itself, with no human presence. Green Planets states that Solaris "resists both physical and epistemic human penetration", describing it as "an impervious mirror surface". Ironically, the planet itself appears to experiment on the scientists by reading their thoughts and creating the Phi-creatures.
In 2022, a group of scientists cited the planet Solaris in a study that stated that such superorganism worlds might be the norm, with planets containing individual creatures like Earth - where symbiosis between organisms took billions of years to develop - being the exception to the rule.
See also
Solaris (star)
References
Fictional amorphous creatures
Fictional characters with extrasensory perception
Fictional extraterrestrial characters
Fictional living planets
Fictional oceans and seas
Fictional superorganisms
Stanisław Lem | Solaris (fictional planet) | [
"Biology"
] | 873 | [
"Superorganisms",
"Fictional superorganisms"
] |
78,251,169 | https://en.wikipedia.org/wiki/QSO%20B0153%2B744 | QSO B0153+744 is a quasar located in the constellation of Cassiopeia. It has a redshift of (z) 2.338 and has an optical brightness of mR = 17.5 magnitude. It was first discovered as an astronomical radio source in 1988. The radio spectrum of the source appears as flat when seen at centimeter wavelengths but optically thin at millimeter wavelengths. This object is also classified as radio-loud and exhibits low polarization, making it a low polarized quasar (LPQ).
Description
The radio source of QSO B0153+744 is found to be both one-sided and complex. However, when shown at both frequencies, it is revealed as double source that is embedded inside a halo. In its radio structure, the 15.4 GHz emission is found to be dominated by two main components with a separation gap of 10 milliarcseconds. These two main components are classified as the northern component and southern component respectively. The northern component contains an inverted spectrum whereas the southern component has a steep spectra.
In 1997, these two components of QSO B0153+744 were studied further. This in turn, were confirmed as a jet-core component and a bright secondary component. The former shows core-jet structure made up of four distinctive components, when resolved at 1.3 centimeter (cm) wavelengths whereas the latter is stationary and exhibits a complicated structure. Further evidence shows the spectral index of the bright component's emission is near to one of the steep-spectrum jet components at ranges between 6 cm and 3.6 cm.
A strong one-sided jet is present in QSO B0153+744 with its projected direction changing by an 180° angle. There are three other sub-components present (the jet's innermost regions). The two sub-components are shown trailing the jet's direction with a switch of 65° ± 3° at distance r = (0.65 ± 0.05) mas to 88° ± 8° at distance r = (1.35 ± 0.05) mas, while the third sub-component is trailing the jet's outermost regions. Based on the jet's speed and its change of direction, this indicates the radio source of QSO B0153+744 is relatively young.
References
External links
QSO B0153+744 on SIMBAD
QSO B0153+744 on NASA/IPAC Database
Quasars
Cassiopeia (constellation)
Astronomical objects discovered in 1988
Active galaxies | QSO B0153+744 | [
"Astronomy"
] | 529 | [
"Cassiopeia (constellation)",
"Constellations"
] |
78,251,375 | https://en.wikipedia.org/wiki/Fazamorexant | Fazamorexant (; developmental code name YZJ-1139) is an orexin receptor antagonist which is under development for the treatment of insomnia. It is taken by mouth.
The drug acts as a dual orexin receptor antagonist (DORA), or as an antagonist of both the orexin OX1 and OX2 receptors.
Fazamorexant is under development by Jiangsu Yangtze River Pharmaceutical Group and/or Shanghai Haiyan Pharmaceutical Technology in China. As of September 2022, it is in phase 3 clinical trials for insomnia. Relatively little public information is available on fazamorexant. This was such that it had to be excluded from a 2020 literature review of orexin receptor antagonists for insomnia.
References
Experimental drugs
Hypnotics
Orexin antagonists
Sedatives
Fluoroarenes
Ketones
2-Pyridyl compounds
Pyrimidines
Tropanes
Carboxamides | Fazamorexant | [
"Chemistry",
"Biology"
] | 193 | [
"Hypnotics",
"Behavior",
"Ketones",
"Functional groups",
"Sleep"
] |
78,251,481 | https://en.wikipedia.org/wiki/Dou%20%28volume%29 | Dou (), called to in Japan and du in Korea, is a unit of volume in East Asia. It originated in China and later spread to Japan, Korean and other places. One dou equals 10 sheng or 1/10 dan, is 10 liters in China, 18.039 liters in Japan and 18 liters in Korea.
Dou is one of the traditional Chinese units of measurement used to measure cereal grains, among other things.
China
Japan
Korea
For more details, please see Sheng (volume)
Words
斗室 (dǒu shì)
車載斗量 (chē zài dǒu liàng)
不為五斗米折腰 (bù wèi wǔ dǒu mǐ zhéyāo)
See also
Chinese units of measurement
Japanese units of measurement
Korean units of measurement
:zh:中國度量衡
Notes
References
Units of volume
Customary units of measurement | Dou (volume) | [
"Mathematics"
] | 178 | [
"Units of volume",
"Quantity",
"Customary units of measurement",
"Units of measurement"
] |
78,251,489 | https://en.wikipedia.org/wiki/PKS%201424-418 | PKS 1424-418 is a blazar located in the constellation of Centaurus. It has a redshift of 1.522 and was first discovered in 1971 by astronomer Keith Peter Tritton who identified the object as ultraviolet-excessive. This object is also highly polarized with a compact radio source. The radio spectrum of this source appears flat, making it a flat-spectrum radio quasar.
PKS 1424-418 is found optically variable on the electromagnetic spectrum. It is a strong source of gamma rays. Between 2008 and 2011, PKS 1424-418 showed four phases of bright flares at GeV energies. The flares have a high correlation between the energy ranges with the exception of one flare that occurred at the same time it showed low gamma activity. In April 2013, it underwent a major gamma ray outburst with its peak flux reaching values of F(> 100 MeV) > 3 x 10−6 ph cm−2 s−1. According to Large Area Telescope observations, this emission originated beyond its broad-line region. A near-infrared flare was witnessed in PKS 1424–418 in January 2018. In August 2022, it once again displayed an episode of rapid flaring activity in both gamma ray and optical bands.
PKS 1424-418 contains a radio structure, comprising a strong radio core and a weaker component with a position angle of 260°. Further observations also showed the core has a size of 0.4 mas with extended emission at both the core's position and northwest. In addition, the core has a flat spectral index of -0.04. A jet is seen extending west from the core before becoming diffused.
Between May 2009 and September 2019, the gamma ray emission from PKS 1424-418 was found to undergo a quasi-periodic oscillation with a 353-day flux oscillation period. A 355-day period with high significance level is also confirmed by adopting time domain methods. This might be explained by orbital motion of a binary supermassive black hole system with the mass of a primary black hole being M ~ 3.5 x 108 - 5.5 x 109 Mʘ.
References
External links
PKS 1424-418 on SIMBAD
PKS 1424-418 on NASA/IPAC Database
Blazars
Quasars
Centaurus
2827996
Active galaxies
Astronomical objects discovered in 1971 | PKS 1424-418 | [
"Astronomy"
] | 497 | [
"Centaurus",
"Constellations"
] |
78,251,560 | https://en.wikipedia.org/wiki/Arrhenius%20Plaque | The Arrhenius Plaque (Swedish: Arrhenius-plaketten) is awarded annually by the Swedish Chemical Society in memory of Svante Arrhenius, a Swedish physicist, chemist, and long-time member of the society, "to a person or persons who have distinguished themselves through outstanding research in the field of chemistry or who have performed valuable work for the good of the Swedish Chemical Society".
Past recipients include Ragnar Ryhage (1962), Jerker Porath and Per Flodin (1963), Carl-Ivar Brändén (1976), Svante Wold (1984), Gunnar von Heijne (1997), Per Claesson (2008), Jonas Bergquist (2009), Lisbeth Olsson (2018) and Berit Olofsson (2021)
References
Chemistry awards
Science and technology awards
Swedish science and technology awards | Arrhenius Plaque | [
"Technology"
] | 183 | [
"Science and technology awards",
"Chemistry awards",
"Science award stubs"
] |
78,252,468 | https://en.wikipedia.org/wiki/Balansiopsis | Balansiopsis is a genus of fungi in the family Clavicipitaceae.
Species in this genus include:
Balansiopsis ascelerotiaca
Balansiopsis asclerotiaca
Balansiopsis asclerotica
Balansiopsis gaduae
Balansiopsis guareae
Balansiopsis pilulaeformis
Balansiopsis piluliformis
Balansiopsis schumanniana
References
Clavicipitaceae
Hypocreales genera | Balansiopsis | [
"Biology"
] | 103 | [
"Fungus stubs",
"Fungi"
] |
78,253,435 | https://en.wikipedia.org/wiki/Polycephalomyces | Polycephalomyces is a genus of fungi in the family Ophiocordycipitaceae.
Species
The following species are recognised in the genus Polycephalomyces:
Polycephalomyces albiramus
Polycephalomyces cylindrosporus
Polycephalomyces ditmarii
Polycephalomyces elaphomyceticola
Polycephalomyces formosus
Polycephalomyces kanzashianus
Polycephalomyces paludosus
Polycephalomyces ponerae
Polycephalomyces ramosus
Polycephalomyces tomentosus
References
Clavicipitaceae
Hypocreales genera | Polycephalomyces | [
"Biology"
] | 150 | [
"Fungus stubs",
"Fungi"
] |
78,254,210 | https://en.wikipedia.org/wiki/Strictification | In mathematics, specifically in category theory, a strictification refers to statements of the form “every weak structure of some sort is equivalent to a stricter one.” Such a result was first proven for monoidal categories by Mac Lane, and it is often possible to derive strictifications from coherence results and vice versa.
Monoidal category
Every monoidal category is monoidally equivalent to a strict monoidal category. This is (essentially) the Mac Lane coherence theorem.
See also
Coherence condition
Notes
Reference
§3. Strict Monoidal Categories
External links
Category theory | Strictification | [
"Mathematics"
] | 119 | [
"Functions and mappings",
"Mathematical structures",
"Mathematical objects",
"Fields of abstract algebra",
"Mathematical relations",
"Category theory"
] |
78,254,826 | https://en.wikipedia.org/wiki/Solar%20wind%20turbulence | Solar wind turbulence refers to the complex, chaotic fluid motions and magnetic field fluctuations observed in the solar wind plasma as it flows outward from the Sun. This turbulence plays a key role in heating the solar wind and accelerating charged particles throughout the heliosphere.
Solar wind turbulence displays both magnetohydrodynamic (MHD) and kinetic plasma behaviors. It exhibits Kolmogorov-like power spectra at fluid scales, and shows strong Alfvénic correlations between velocity and magnetic field fluctuations, especially in fast solar wind. It evolves with distance from the Sun as the wind expands.
The turbulence can be broadly categorized into:
Large-scale Alfvénic fluctuations originating from the Sun
Actively evolving turbulent cascade transferring energy to smaller scales
Small-scale kinetic processes where the fluid approximation breaks down
Observations from spacecraft like Helios, Ulysses, and Wind have revealed that solar wind turbulence properties vary between:
Fast vs. slow solar wind streams
Different heliographic latitudes
Various distances from the Sun
Current research focuses on the relative roles of waves vs. structures, evolution of turbulent properties with solar wind expansion, and kinetic processes at small scales where energy dissipates.
Further reading
References
Plasma phenomena
Sun | Solar wind turbulence | [
"Physics"
] | 240 | [
"Plasma phenomena",
"Physical phenomena",
"Plasma physics"
] |
78,255,463 | https://en.wikipedia.org/wiki/Octadecanolide | Octadecanolide is an organic compound with the chemical formula . It is a cyclic ester or lactone, more specifically a macrolide.
Occurrence
Several species of bees (such as some of genera Colletes, Halictus, Lasioglossum) and butterflies (such as some of genus Heliconius) use octadecanolide as a pheromone. The Dufour's gland of bees in the Halictinae subfamily, contains octadecanolide along with other macrocyclic lactones, which could be used for a range of different applications like nest building, larval food and chemical communication.
References
Lactones
Heterocyclic compounds with 1 ring
Pheromones | Octadecanolide | [
"Chemistry"
] | 150 | [
"Chemical ecology",
"Organic compounds",
"Pheromones",
"Organic compound stubs",
"Organic chemistry stubs"
] |
78,257,125 | https://en.wikipedia.org/wiki/List%20of%20Fast-track%20Approvals%20Bill%20projects | The Fast-track Approvals Bill project list is a list of the 149 projects seeking approval through the Fast-track Approvals Bill in New Zealand.
The list of projects to be included in the Bill was released publicly on 6 October 2024. The list includes 44 housing developments, 7 aquaculture and farming projects, 43 infrastructure projects, 22 renewable energy projects, and 11 mining and quarrying projects. The locations of some projects were unspecified, such as the Waikato-based 'Green Steel' project to recycle shredded steel. The list included some projects, such as Trans-Tasman Resources' proposed sea bed mining project, and the Waitaha Hydro Project, that had been previously rejected due to their likely adverse environmental effects.
On 31 October the Auditor-General announced that he would conduct an enquiry into how conflicts of interest were identified and handled in the project selection process. Radio New Zealand reported that "companies and shareholders associated with 12 projects gave more than $500,000 in political donations to National, ACT and New Zealand First".
References
Urban planning in New Zealand
Economy of New Zealand
Environmental law in New Zealand
Environmental mitigation
Natural resource management
Sixth National Government of New Zealand
Projects in Oceania | List of Fast-track Approvals Bill projects | [
"Chemistry",
"Engineering"
] | 244 | [
"Environmental mitigation",
"Environmental engineering"
] |
78,259,180 | https://en.wikipedia.org/wiki/Zhejiang%20Jingsheng%20Mechanical%20%26%20Electrical | Zhejiang Jingsheng Mechanical & Electrical (JSG; ) is a publicly listed Chinese company that engages in the development and sale of semiconductor related equipment and materials such as Silicon carbide (SiC). It provides products and services to the semiconductor and photovoltaic industries.
Background
In 2005, Zhejiang University mechanical engineering professor, Qiu Minxiu retired from her post at the university. She is the wife of Lu Yongxiang who at the time was President of the Chinese Academy of Sciences. In 2006, Qiu lead a project that involved electromechanical companies and universities such as Zhejiang University and Hangzhou Dianzi University which would develop technologies related to growingmonocrystalline silicon. Near the end of the year, JSG was established as a company to commercialize the project.
On 11 May 2012, JSG held its initial public offering becoming a listed company on the Shenzhen Stock Exchange.
In 2016, Qiu stepped down from managing JSG. She was succeeded by her former student, Cao Jianwei who became chairman and her son, He Jun who became CEO.
Since 2017, JSG has been deeply engaged in SiC ingot growth equipment and process development, achieving the successful production of 6-inch and 8-inch SiC ingots and substrates.
JSG attempted to set up a joint venture with the Hong Kong arm of Applied Materials to buy it's screen printing equipment business in Italy. However, in November 2021, Italian prime minister Mario Draghi vetoed the takeover to prevent it proceeding. The reason was the takeover could have consequences in the strategic semiconductor sector for Italy.
See also
Silicon carbide
Applied Materials
Semiconductor industry in China
References
External links
2006 establishments in China
2012 initial public offerings
Companies based in Hangzhou
Companies listed on the Shenzhen Stock Exchange
Electronics companies established in 2006
Equipment semiconductor companies
Semiconductor companies of China
Solar energy companies of China | Zhejiang Jingsheng Mechanical & Electrical | [
"Engineering"
] | 378 | [
"Equipment semiconductor companies",
"Semiconductor fabrication equipment"
] |
78,259,344 | https://en.wikipedia.org/wiki/Luxdegalutamide | Luxdegalutamide, also known as ARV-766, is an investigational oral androgen receptor (AR) degrader being developed by Arvinas for the treatment of metastatic castration-resistant prostate cancer (mCRPC). It belongs to a class of drugs called proteolysis targeting chimeras (PROTACs), which are designed to selectively degrade specific proteins by hijacking the ubiquitin-proteasome system. Luxdegalutamide is a second-generation PROTAC AR degrader that has demonstrated a broader efficacy profile and better tolerability compared to its predecessor, ARV-110, in clinical settings. It has shown promise in overcoming resistance associated with certain AR mutations, including the L702H mutation, which is prevalent in up to 24% of treated mCRPC patients. As of 2024, luxdegalutamide is being evaluated in phase I/II clinical trials for prostate cancer.
References
Benzamides
Benzonitriles
Cyclobutanes
Fluorobenzenes
Piperazines
Piperidines
Resorcinols | Luxdegalutamide | [
"Chemistry"
] | 233 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
78,259,470 | https://en.wikipedia.org/wiki/Gridegalutamide | Gridegalutamide is an investigational oral androgen receptor (AR) degrader being developed for the treatment of metastatic castration-resistant prostate cancer (mCRPC). It belongs to a class of drugs called proteolysis targeting chimeras (PROTACs), which are designed to selectively degrade specific proteins by hijacking the ubiquitin-proteasome system. CC-94676 employs a unique dual mechanism of action, combining AR degradation with AR antagonism, potentially offering advantages over traditional AR inhibitors in overcoming resistance mechanisms. Initially developed by Celgene and now under Bristol Myers Squibb, CC-94676 has demonstrated AR protein degradation and suppression of tumor growth in CRPC mouse models. As of 2024, CC-94676 is being evaluated in phase I clinical trials for patients with mCRPC who have progressed on androgen-deprivation therapy and at least one prior secondary hormonal therapy.
References
Acetanilides
Benzonitriles
Trifluoromethyl compounds
Piperidines
Nitriles
Imidazolidinones
Piperazines | Gridegalutamide | [
"Chemistry"
] | 236 | [
"Pharmacology",
"Functional groups",
"Medicinal chemistry stubs",
"Pharmacology stubs",
"Nitriles"
] |
78,259,584 | https://en.wikipedia.org/wiki/Facer.io | Facer is one of the largest watch face platforms for Apple Watch, Wear OS, and Tizen-based smartwatches, developed by Los Angeles-based Little Labs, Inc. It allows users to select from over 500,000 premade watch faces or create custom designs through its web-based editor.
Overview
Facer was launched in 2015 as a platform for Android and Wear OS smartwatches. In March 2016, the platform expanded to support iOS and Apple Watch. The service gained popularity for providing users with a large selection of watch faces, both from independent designers and branded partnerships. Facer has licensing agreements with brands, such as Star Trek, Fallout, US Air Force, Atari, Barbie, DOOM, Dungeons and Dragons, U.S. Space Force, Tetris, Teenage Mutant Ninja Turtles and more.
The platform supports all major smartwatches, including Wear OS, watchOS and Tizen. Facer hosts a library of over 500,000 watch faces designed by more than 50,000 creators. The platform allows users to browse and download a wide variety of designs themed around various genres and styles. Users can access the platform for free, though some premium watch faces require in-app purchases. Facer also allows users interested in designing to create their own watch faces through its web-based editor, Facer Creator.
Little Labs, Inc., the company behind Facer, is headquartered in Los Angeles, California.
References
American websites
Smartwatches | Facer.io | [
"Technology"
] | 298 | [
"Smartwatches"
] |
78,259,792 | https://en.wikipedia.org/wiki/Zofija%20Mazej%20Kukovi%C4%8D | Zofija Mazej Kukovič (born 14 May 1955) is a Slovenian electrical engineer who became a manager and a politician. She was the minister of health 2007–8 before she was a member of the European Parliament for the Slovenian Democratic Party.
Life
Kukovič was born in Črna na Koroškem in 1955. She studied informatics and later electronics at the University of Maribor. She later passed an MBA after a year's study at the Faculty of Management in Brdo pri Kranju. She speaks English, Croatian and Serbian.
In 1992 she was working for the ESO company when it divided into two halves. She led the part that became the ESO Montaža company which was heading for bankruptcy. She turned the company around and into profit.
Kukovič led the company Esotech until 3 July 2007. She served as the minister of health until 2008 after she joined the 8th Government of Slovenia in October 2007 following a reshuffle caused by the resignation of three of Janez Janša's ministers. Her appointment was agreed by eight of the members of parliament on the health committee despite her lack of experience in health. One member voted against.
She went on to eventually become a member of the European Parliament. In the 2009 European parliament elections, she was third choice on the Slovenian Democratic Party's electoral list. The party, however, only won two seats, but after the Lisbon Treaty was agreed, Kukovič became eligible to take up an additional eighth seat in the European Parliament allocated to Slovenia. She finally became an MEP on 8 December 2011, serving until the end of the term in 2014. In early 2014 she was one of four European Members of Parliament who were invited to debate issues around the right to vote by Euronat. The debate in Slovenian was intended to increase voter participation in the forthcoming elections.
References
1955 births
Living people
Slovenian politicians
Electrical engineers
Members of the European Parliament for Slovenia
Government ministers
People from the Municipality of Črna na Koroškem | Zofija Mazej Kukovič | [
"Engineering"
] | 404 | [
"Electrical engineering",
"Electrical engineers"
] |
78,260,418 | https://en.wikipedia.org/wiki/Vista%20paradox | The Vista paradox is a natural optical illusion where an object seen through an aperture appears to shrink in apparent size as the observer approaches the aperture. The paradox takes place when the distant object that seems to be shrinking or enlarging as its visual angle respectively increases or decreases is many times further away than the maximum distance between the observer and the aperture.
See also
Depth perception
Forced perspective
Perceived visual angle
Perspective distortion (photography)
References
External links
Special effects
Optical illusions
Visual perception | Vista paradox | [
"Physics"
] | 94 | [
"Optical phenomena",
"Physical phenomena",
"Optical illusions"
] |
78,261,000 | https://en.wikipedia.org/wiki/NGC%203817 | NGC 3817 is a barred spiral galaxy located approximately 91.7 million light-years away in the constellation Virgo. It was discovered by the German-British astronomer William Herschel on March 15, 1784, using his telescope in Slough, England. Classified as a LINER-type Active Galactic Nucleus (AGN), NGC 3817 exhibits low-ionization nuclear emission lines from its core. With an apparent magnitude of 14.4, the galaxy features a faint ring structure and loosely wound spiral arms.
References
Barred spiral galaxies
3817
Galaxy stubs
Virgo (constellation)
Galaxies discovered in 1784 | NGC 3817 | [
"Astronomy"
] | 122 | [
"Virgo (constellation)",
"Galaxy stubs",
"Astronomy stubs",
"Constellations"
] |
78,261,741 | https://en.wikipedia.org/wiki/NGC%203776 | NGC 3776 is a spiral galaxy located in the constellation Virgo. It is classified as an Sb-type galaxy, which signifies it has moderately tightly wound spiral arms. This galaxy was discovered in 1886 by astronomer Ormond Stone, known for his work cataloging celestial objects in the southern hemisphere. NGC 3776 has a visual magnitude of 16, making it challenging to observe without a telescope. The galaxy is cataloged within the New General Catalogue (NGC), a comprehensive listing of deep-sky objects compiled by John Louis Emil Dreyer in 1888 to include discoveries like Stone’s.
Characteristics
NGC 3776 is an Sb-type spiral galaxy, characterized by its moderately tight spiral arms. Located in the constellation Virgo, this galaxy is observable at right ascension 11h 38m 17.98s and declination -03° 21′ 15.8″. The galaxy has an apparent visual magnitude of 16.0, making it relatively faint and challenging to view without advanced telescopic equipment. Its radial velocity of approximately 11,130 km/s and redshift of 0.03784 indicate a substantial recessional velocity, which is consistent with galaxies positioned at considerable distances from Earth.
NGC 3776 has a surface brightness of about 23.0 mag/arcsec2, which suggests that it appears dim against the night sky. With an angular size of 0.48′ by 0.38′, it occupies a small region when viewed from Earth. These measurements highlight its remoteness and modest luminosity compared to more prominent galaxies.
History
NGC 3776 was discovered in 1886 by the American astronomer Ormond Stone, who made significant contributions to the study of southern hemisphere celestial objects during his tenure at the Leander McCormick Observatory in Virginia.
References
Spiral galaxies
3776
Virgo (constellation) | NGC 3776 | [
"Astronomy"
] | 372 | [
"Virgo (constellation)",
"Constellations"
] |
78,262,006 | https://en.wikipedia.org/wiki/Eicosanolide | Eicosanolide is an organic compound with the chemical formula . It is a cyclic ester or lactone, more specifically a macrolide.
Occurrence
Eicosanolide is used by several species of bees (such as some of genera Colletes, Lasioglossum, Halictus) and butterflies (such as some of genus Heliconius) as a pheromone. The Dufour's gland of bees in the Halictinae subfamily, contains eicosanolide along with other macrocyclic lactones, which could be used for a range of different applications like nest building, larval food and chemical communication.
References
Lactones
Heterocyclic compounds with 1 ring | Eicosanolide | [
"Chemistry"
] | 151 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
78,262,034 | https://en.wikipedia.org/wiki/NGC%203833 | NGC 3833 is a barred spiral galaxy located in the constellation Virgo, about 280 million light-years from Earth. Discovered by astronomer William Herschel on April 15, 1784, NGC 3833 has a Hubble classification of "Sc," indicating loosely wound spiral arms and a relatively small central bulge. The galaxy spans roughly 1.4 by 0.7 arcminutes in the night sky and shines with an apparent magnitude of around 13.5, making it a faint object suitable for observation with larger telescopes.
Due to its distance and redshift (z ≈ 0.020214), NGC 3833 is part of the large Virgo Cluster of galaxies, a group containing thousands of galaxies. In various catalogs, it is also known as PGC 36441 and UGC 6692.
Characteristics
NGC 3833 is classified as a barred spiral galaxy (type Sc) within the constellation Virgo. It exhibits a loosely wound structure with a small central bulge, characteristic of its classification. The galaxy spans approximately 1.4 arcminutes in length and 0.7 arcminutes in width, making it relatively small in apparent size compared to other galaxies.
With an apparent magnitude of around 13.5, NGC 3833 is a faint object that requires moderate to large telescopes for observation. It has a surface brightness of 13.3 magnitudes per square arcminute, indicating how dim it appears against the background of the night sky. The galaxy's redshift value of 0.020214 translates to a recessional velocity of approximately 6,060 km/s, placing it roughly 280 million light-years away from Earth.
References
Barred spiral galaxies
3833
Virgo (constellation)
Discoveries by William Herschel
Galaxies discovered in 1784 | NGC 3833 | [
"Astronomy"
] | 362 | [
"Virgo (constellation)",
"Constellations"
] |
63,798,100 | https://en.wikipedia.org/wiki/Human%20Cell%20Atlas | The Human Cell Atlas is a global project to describe all cell types in the human body. The initiative was announced by a consortium after its inaugural meeting in London in October 2016, which established the first phase of the project. Aviv Regev and Sarah Teichmann defined the goals of the project at that meeting, which was convened by the Broad Institute, the Wellcome Trust Sanger Institute and Wellcome Trust. Regev and Teichmann lead the project. As of 2024, the project has mapped approximately 62 million human cells into 18 biological networks, which includes cells from vital systems such as the nervous system, lungs, heart, intestine and immune system.
Description
The Human Cell Atlas will catalogue a cell based on several criteria, specifically the cell type, its state, its location in the body, the transitions it undergoes, and its lineage. It will gather data from existing research, and integrate it with data collected in future research projects. Among the data it will collect is the fluxome, genome, metabolome, proteome, and transcriptome.
Its scope is to categorize the 37 trillion cells of the human body to determine which genes each cell expresses by sampling cells from all parts of the body.
All aspects of the project will be made "available to the public for free", including software and results.
By April 2018, the project included more than 480 researchers conducting 185 projects.
Funding
In October 2017, the Chan Zuckerberg Initiative announced funding for 38 projects related to the Human Cell Atlas. Among them was a grant of undisclosed value to the Zuckerman Institute of the Columbia University Medical Center at Columbia University. The grant, titled "A strategy for mapping the human spinal cord with single cell resolution", will fund research to identify and catalogue gene activity in all spinal cord cells. The Translational Genomics Research Institute received a grant to develop a standard for the "processing and storage of solid tissues for single-cell RNA sequencing", compared to the typical practice of relying on the average of sequencing multiple cells. Project home pages are available at the Chan Zuckerberg Initiative's website.
The program is also backed by European Union, the National Institutes of Health in the United States, and the Manton Foundation.
Data
In April 2018, the first data set from the project was released, representing 530,000 immune system cells collected from bone marrow and cord blood.
A research program at the Max Planck Institute of Immunobiology and Epigenetics published an atlas of the cells of the liver, using single-cell RNA sequencing on 10,000 normal cells obtained from nine donors.
The Tabula Sapiens data was published on a dedicated website.
See also
List of distinct cell types in the adult human body
ENCODE - Encyclopedia of DNA Elements (ENCODE)
Human Genome Project
Human Protein Atlas
Human Biomolecular Atlas Program
Notes
References
Further reading
External links
Biological databases
Proteomics
Online databases | Human Cell Atlas | [
"Biology"
] | 593 | [
"Bioinformatics",
"Biological databases"
] |
63,798,653 | https://en.wikipedia.org/wiki/Cross%20dehydrogenative%20coupling | Cross dehydrogenative coupling (also known as CDC reaction), coined by Chao-Jun Li of McGill University, is a type of coupling reaction allowing the construction of a carbon–carbon bond or C-Heteroatom bond directly from C-H bonds in the presence of an oxidant, leading to the thermodynamically unfavorable formal removal of a H2 molecule. As such, CDC are couplings belonging to the C-H activation strategy.
The key to the CDC coupling is eliminating the need for substrate prefunctionalization. Therefore, the CDC reaction has the advantages of high efficiency, Atom economy and environmental friendliness. Such reactions can be achieved or activated by transition-metal catalysis or oxidation reaction (e.g. benzoquinone, peroxides, O2, hypervalent iodine), or by either photocatalysis or electrocatalysis. The mechanism and reactivity of the CDC reactions varies dramatically depending on the substrate. CDC reactions have been used to construct bonds between sp3-sp3, sp3-sp2, sp3-sp, sp2-sp2, sp2-sp and sp-sp C-H bonds. The synthesis and functionalization of various nitrogen, oxygen and sulfur-containing heterocycles have also been achieved via CDC.
See also
C-H activation
Cross-coupling
Atom economy
Oxidative coupling
References
Coupling reactions
Organometallic chemistry
Carbon-carbon bond forming reactions
Catalysis | Cross dehydrogenative coupling | [
"Chemistry"
] | 310 | [
"Catalysis",
"Carbon-carbon bond forming reactions",
"Coupling reactions",
"Organic reactions",
"Chemical kinetics",
"Organometallic chemistry"
] |
63,801,136 | https://en.wikipedia.org/wiki/Titanium%28II%29%20bromide | Titanium(II) bromide is the inorganic compound with the formula TiBr2. It is a black micaceous solid. It adopts the cadmium iodide structure, featuring octahedral Ti(II) centers. It arises via the reaction of the elements:
Ti + Br2 → TiBr2
The compound reacts with caesium bromide to give the linear chain compound CsTiBr3.
References
Titanium(II) compounds
Bromides
Titanium halides | Titanium(II) bromide | [
"Chemistry"
] | 98 | [
"Bromides",
"Inorganic compounds",
"Inorganic compound stubs",
"Salts"
] |
63,801,647 | https://en.wikipedia.org/wiki/Linear%20chain%20compound | In chemistry and materials science, linear chain compounds are materials composed of one-dimensional arrays of metal-metal bonded molecules or ions. Such materials exhibit anisotropic electrical conductivity.
Examples
Many linear chain compounds feature square planar complexes. One example is , which stack with distances of about 326 pm. Classic examples include Krogmann's salt and Magnus's green salt. Another example is the partially oxidized derivatives of . The otherwise ordinary complex gives an electrically conductive derivative upon oxidation, e.g., with bromine to give , where x ~0.05. Related chlorides have the formulae and .
In contrast to linear chain compounds, extended metal atom chains (EMACs) are molecules or ions that consist of a finite, often short, linear strings of metal atoms, surrounded by organic ligands.
One group of platinum chains is based on alternating cations and anions of (R = iPr, , ) and . These may be able to be used as vapochromic sensor materials, or materials which change color when exposed to different vapors.
Linear chains of Pd-Pd bonds protected by a "π-electron sheath" are known.
Not only do these olefin-stabilized metal chains constitute a significant contribution to the field of organometallic chemistry, both the complex's metal atom structures and the olefin ligands themselves can conduct a current.
Methodology
Some linear chain compounds are produced or fabricated by electrocrystallization. The technique is used to obtain single crystals of low-dimensional electrical conductors.
See also
platinum pop
References
Nanotechnology
Conductive polymers
Molecular electronics
Semiconductor material types | Linear chain compound | [
"Chemistry",
"Materials_science",
"Engineering"
] | 335 | [
"Molecular physics",
"Semiconductor materials",
"Molecular electronics",
"Materials science",
"Nanotechnology",
"Semiconductor material types",
"Conductive polymers"
] |
63,802,762 | https://en.wikipedia.org/wiki/Mixed-anion%20compounds | Mixed-anion compounds, heteroanionic materials or mixed-anion materials are chemical compounds containing cations and more than one kind of anion. The compounds contain a single phase, rather than just a mixture.
Use in materials science
By having more than one anion, many more compounds can be made, and properties tuned to desirable values.
In terms of optics, properties include phosphorescence, photocatalysis, laser damage threshold, refractive index, birefringence, absorption particularly in the ultraviolet or near infrared, non-linearity.
Mechanical properties can include ability to grow a large crystal, ability to form a thin layer, strength, or brittleness.
Thermal properties can include melting point, thermal stability, phase transition temperatures, thermal expansion coefficient.
For electrical properties, electric conductivity, band gap, superconducting transition temperature piezoelectricity, pyroelectricity, ferromagnetism, dielectric constant, charge-density wave transition can be adjusted.
Production
Many of the non-metals that could make mixed-anion compounds may have greatly varying volatilities. This makes it more difficult to combine the elements together. Compounds may be produced in a solid state reaction, by heating solids together, either in a vacuum or a gas. Common gases used include, oxygen, hydrogen, ammonia, chlorine, fluorine, hydrogen sulfide, or carbon disulfide. Soft chemical approaches to manufacture include solvothermal synthesis, or substituting atoms in a structure by others, including by water, oxygen, fluorine, or nitrogen. Teflon pouches can be used to separate different formulations. Thin film deposits can yield strained layers. High pressures can be used to prevent evaporation of volatiles. High pressure can result in different crystal forms, perhaps with higher coordination number.
Kinds
Elemental
pnictochalcogenides
oxypnictides, including oxynitrides, oxyphosphides, oxyarsenides, oxyantimonides, oxybismuthides
chalcohalides or chalcogenide halides
oxohalides, including oxyfluorides, oxychlorides, oxybromides, oxyiodides
fluorosulfides
sulfide chlorides, selenide chlorides, telluride chlorides
sulfide bromides, selenide bromides, telluride bromides
sulfide iodides, selenide iodides, telluride iodides
oxysulfides, oxyselenides
oxyhydrides
halopnictides
fluoropnictides, including fluorophosphides, fluoroarsenides, fluoroantimonides, fluorobismuthides, arsenide chlorides
Molecular anions
borohydride-chloride
disulfide dithioorthovanadate
Oxyanions
halocarbonates, including carbonate fluorides, carbonate chlorides, carbonate bromides
phosphates, including fluoride phosphates, chloride phosphate, phosphate molybdates, phosphate arsenates
borates
halide borates, including fluoride borates borate chlorides, borate bromides, borate iodides
chalcogenide borates, including sulfide borates
borate carbonates, borate nitrates, borate sulfates, borate phosphates
borate acetates
Condensed borates: borosulfates, boroselenates, borotellurates, boroantimonates, borophosphates, boroselenites
sulfates
sulfate fluorides, sulfate chlorides
sulfate arsenate
selenite fluorides
iodate fluorides
Silicates
sulfide silicates
Fluoroanions
Mixed valency and oligomers
Some elements can form several kinds of anions, and compounds may exist with more than one. Examples include the iodate periodates, sulfite sulfates, selenate selenites, tellurite tellurates, nitrate nitrites, phosphate phosphites, and arsenate arsenites.
These kinds also include different oligomeric forms such as phosphates or fluorotitanates, such as [Ti4F20]4- and [TiF5]−.
Organic
borate acetate
oxalate formate
References
Physical chemistry | Mixed-anion compounds | [
"Physics",
"Chemistry"
] | 911 | [
"Matter",
"Applied and interdisciplinary physics",
"Mixed anion compounds",
"nan",
"Physical chemistry",
"Ions"
] |
63,804,547 | https://en.wikipedia.org/wiki/TMC-647055 | TMC-647055 is an experimental antiviral drug which was developed as a treatment for hepatitis C, and is in clinical trials as a combination treatment with ribavirin and simeprevir. It acts as a NS5b polymerase inhibitor.
References
Anti–RNA virus drugs
Antiviral drugs | TMC-647055 | [
"Biology"
] | 65 | [
"Antiviral drugs",
"Biocides"
] |
63,804,772 | https://en.wikipedia.org/wiki/Merimepodib | Merimepodib (VX-497) is a drug which acts as an inhibitor of the enzyme inosine monophosphate dehydrogenase, which is required for the synthesis of nucleotide bases containing guanine. This consequently inhibits synthesis of DNA and RNA, and results in antiviral and immunosuppressive effects. It progressed as far as Phase 2b human clinical trials against Hepatitis C but showed only modest benefits in comparison to existing treatments, however it continues to be researched, and also shows activity against other viral diseases such as Zika virus and foot and mouth disease virus.
Merimepodib was investigated in combination with remdesivir in a phase 2 clinical trial in the U.S. as a potential treatment of COVID-19 by ViralClear Pharmaceuticals. The trial stopped in October 2020, and the company announced in a news release that it was "unlikely that the trial would meet its primary safety endpoints", and that it "does not intend to further develop merimepodib".
References
Anti–RNA virus drugs
Antiviral drugs | Merimepodib | [
"Biology"
] | 227 | [
"Antiviral drugs",
"Biocides"
] |
63,805,254 | https://en.wikipedia.org/wiki/Kennedy%20J.%20P.%20Orton | Kennedy Joseph Previté-Orton (21 January 1872 – 16 March 1930) was a British chemist who became a lecturer and demonstrator at St Bartholomew's Hospital and then became a professor at Bangor. He was also a keen climber, amateur geologist, ornithologist and bird conservationist.
Life and work
Kennedy Orton was born in St. Leonard's on Sea to clergyman William Previté and Eliza Orton. His grandfather was Italian and the name Previte is a Sicilian form of Prete. Kennedy's father studied at St. John's College Cambridge and was thirty-first wrangler in 1860, becoming a vicar in Leicester. After marrying he took the surname of his wife. Kennedy was the eldest son. He studied at Kibworth Grammar School (1882–1885) and then Wyggeston School, Leicester (1885–1888) before pursuing medicine at St. Thomas' Hospital, but there he became interested in chemistry and moved to St. John's College, Cambridge. He then obtained a Ph.D. summa cum laude in Heidelberg under Karl von Auwers, before working for a year with Sir William Ramsey at University College, London. He was then lecturer and demonstrator of Chemistry at St. Bartholomew's Hospital, working under F. D. Chattaway (1860–1944) who would inspire much of his subsequent research. He would examine N-halogen compounds, reaction mechanisms and equilibria. In 1903 he was appointed Professor of Chemistry at University College of North Wales, Bangor, where he headed the department until his death. After World War I, his department in Bangor became a centre for research in physical organic chemistry. He collaborated with Chattaway on the synthesis and study of nitro-halogen componds. He worked on reaction mechanisms and kinetics in collaboration with Arthur Lapworth which led to his breaking away from Chattaway. He was elected a Fellow of the Royal Society in 1921. His collaborators and students included Herbert Ben Watson (1894–1975), Alan Edwin Bradfield (1897–1953), Edward David Hughes (1906–1963), Brynmor Jones (1903–1989), Gwyn Williams (1904–1955), and Frederick George Soper (1898–1982).
Besides being a chemist, he was a keen climber, geologist, and ornithologist, and a biannual ornithological lecture was endowed in his name. He married Annie Ley in 1897 and they had a son and two daughters. He died from pneumonia.
References
Fellows of the Royal Society
Alumni of St John's College, Cambridge
British chemists
Academics of Bangor University
Physical organic chemistry
1872 births
1930 deaths | Kennedy J. P. Orton | [
"Chemistry"
] | 552 | [
"Physical organic chemistry"
] |
63,805,510 | https://en.wikipedia.org/wiki/Electron%20orbital%20imaging | Electron orbital imaging is an X-ray synchrotron technique used to produce images of electron (or hole) orbitals in real space. It utilizes the technique of X-ray Raman scattering (XRS), also known as Non-resonant Inelastic X-Ray Scattering (NIXS) to inelastically scatter electrons off a single crystal. It is an element specific spectroscopic technique for studying the valence electrons of transition metals.
Background
Pictures of electron’s wavefunctions are commonplace in most quantum mechanics textbooks. However, the images shown of these orbital shapes of these electrons are entirely mathematical constructs. As a purely experimental technique electron orbital imaging has the ability to solve some problems in condensed matter physics without the use of complementary theoretical approaches. Theoretical approaches, while indispensable, invariably rely on several underlying assumptions, which vary depending on the approach used. The motivation for developing orbital imaging stemmed from the desire to omit the complex theoretical calculations to model experimental spectra; and instead simply “see” the relevant occupied and unoccupied electron orbitals.
Experimental setup
The non-resonant inelastic x-ray scattering cross section is orders of magnitude smaller than that of photoelectric absorption. Therefore, high-brilliance synchrotron beamlines with efficient spectrometers that are able to span a large solid angle of detection are required. XRS spectrometers are usually based on spherically curved analyzer crystals that act as focusing monochromator after the sample. The energy resolution is on the order of 1 eV for photon energies on the order of 10 keV.
Briefly put, the technique measures the density of electron holes the valence band in the direction of the momentum transfer vector q (Fig. 1), which is defined as the difference in momentum between the incoming qin and outgoing qout photons. The sample is rotated between subsequent measurement (by some angle θ) such that the momentum transfer vector traverses a plane in the crystal. Because holes are simply the inverse of the electron occupation, the occupied (electrons) and unoccupied (holes) orbitals in a given plane can be imaged. In practice, photons ~10keV are used in order to achieve a sufficiently large q (needed to access dipole forbidden transitions, see below Theoretical Basis). The scattered photons are detected at a constant energy, while the incident photon energy is swept above that over a range corresponding to the binding energy of the relevant excitation. For example, if the energy of the photons detected is 10keV, and the nickel 3s (binding energy of 111eV) excitation is of interest, then the incident photons are swept in a range around 10.111keV. In this manner the energy transferred to the sample is measured. The intensity of a core level electron excitation (such as 3s→3d) is integrated for various directions of the momentum transfer vector q relative to the crystal being measured. An s orbital is the most convenient to utilize because it is spherical, and therefore the technique is sensitive only to the shape of the final wavefunction. As such, the integrated intensity of the resulting spectrum is proportional to the hole density in direction of q.
Theoretical basis
The technique is hinged on its ability to access dipole forbidden electronic transitions.
The double differential cross section for a NIXS measurement is given by:
where (dσ/dΩ)Th is the Thomson scattering cross-section (representing the elastic scattering of electromagnetic waves off electrons) and S(q,ω) is the dynamic structure factor, which contains the physics of the material being measured, and is given by:
where q = kf - ki is the momentum transfer and the delta function δ conserves energy: ω is the photon energy loss and Ei & Ef are the initial and final states of the system, respectively. If q is small then the Taylor expansion of the transition matrix eiq·r implies that only the first (dipole) term in the expansion is important. Orbital imaging relies of the fact that as the momentum transfer increases (~4 to 15 Å−1) further terms in the expansion of the transition matrix become relevant, which allows the experimenter to observe higher multipole transitions (quadrupole, octupole, etc.).
Applications
Electron orbital imaging has applications in solid state physics wherein the primary goal is to understand the observed bulk properties of a given material—whether electronic or magnetic—from the atomic perspective of the constituent electrons. In many materials it is the case is that there is a delicate balance of competing interactions that together stabilize a particular orbital state, which in turn determines the physical properties. Electron Orbital Imaging allows scientists to directly image the valence electron orbitals in real space. This has the advantage of bypassing theoretical modelling of experimental spectra (which is often an intractable problem), and observing the relevant orbitals directly.
The first application of the technique was published in 2019 and showed the 3d orbitals (specifically the holes, which are the inverse of the electrons) of Nickel(II) oxide. The shape of the eg orbitals were imaged in real space through a cross-sectional cut of a single crystal of NiO.
It has also been applied to the Ising magnetic material Ca3Co2O6 (Fig. 2) in order to show specifically that it is the sixth electron on the high-spin trigonally coordinated cobalt site that gives rise to the observed bulk large orbital magnetic moment.
References
X-ray scattering
X-ray spectroscopy
Raman scattering | Electron orbital imaging | [
"Physics",
"Chemistry"
] | 1,139 | [
"Spectrum (physical sciences)",
"X-ray scattering",
"Scattering",
"X-ray spectroscopy",
"Spectroscopy"
] |
63,806,773 | https://en.wikipedia.org/wiki/First%20Derm | First Derm is a US-based online dermatology and tele-health website providing answers to skin conditions. Users send in cases to board certified dermatologists via an iOS, Android or Web app.
History
First Derm was founded in 2014 by Dr. Alexander Börve to support dermatologists in treating patients online. Dr. Börve studied at the Sahlgrenska Academy based in The University of Gothenburg, where he was a researcher in mobile health and tele-dermatology. The research conducted was one of the first of its time, based on using mobile devices as a tool to answer questions and queries for dermatologists. The research included a pilot study of the effectiveness of a mobile health service in Sweden, the use of MMS and SMS in teledermatology, and the use of teledermoscopy as a tool to refer possible skin cancer patients to a dermatologist.
Over 300,000 cases have been checked from over 160 countries and the service is available in seven languages.
Purpose
The purpose of First Derm is to provide immediate solutions to skin care concerns without diagnosing the patient. This allows the patient to speed up the referral process and receive surgery or treatment more quickly than the traditional route.
The tool is also used by national health services such as NHSx who employ the tool as a triage solution for doctors.
References
Dermatology
Telemedicine
Health informatics | First Derm | [
"Biology"
] | 295 | [
"Health informatics",
"Medical technology"
] |
63,807,555 | https://en.wikipedia.org/wiki/Stem%20Cell%20Therapeutic%20and%20Research%20Act%20of%202005 | The Stem Cell Therapeutic and Research Act of 2005 () is a United States federal law that assigns the United States Secretary of Health and Human Services to create a national stockpile of cord blood stem cells, and rewrites provisions within the Public Health Service Act to account for cord blood and bone marrow donors.
Legislative history
The House bill (HR-2520) was introduced on May 23, 2005, by Rep. Chris Smith of New Jersey. On December 20, 2005, the bill was signed by the President after passing through both chambers with unanimous consent.
References
Stem cell research
Acts of the 109th United States Congress
United States federal health legislation | Stem Cell Therapeutic and Research Act of 2005 | [
"Chemistry",
"Biology"
] | 130 | [
"Translational medicine",
"Tissue engineering",
"Stem cell research"
] |
63,807,558 | https://en.wikipedia.org/wiki/Apiogalacturonan | Apiogalacturonans are a type of pectin found in the cell walls of Lemna and Zostera marina. Substituted galacturonans are characterized by the presence of the saccharide appendant residue D-apiose in the case of apiogalacturonan, branching from a backbone of D-galacturonic acid residues. According to the Complex Carbohydrate Research Center, "[t]he backbone of these polysaccharides is resistant to fragmentation by microbial EPGs."
Lemnan belongs to rare apiogalacturonic pectic polysaccharides, along with zosteran from Zostera marina.
The apiogalacturonan in Lemna has been studied for several nutritional and biotechnology applications in animal models. In brief, it has been shown to have gastric-protection and immune-adjuvant properties. It is also cryoprotective and this application has been patented.
The apiogalacturonan from Zostera marina currently is used in a variety of cosmetic functions. The German group Beiersdorf AG holds several patents on the application of apiogalacturonan for cosmetic applications. Zostera marina L. was selected for its antioxidative activity and inhibition of matrix metalloproteinase-1 (MMP-1) expression.
References
Polysaccharides | Apiogalacturonan | [
"Chemistry"
] | 291 | [
"Carbohydrates",
"Polysaccharides"
] |
63,809,732 | https://en.wikipedia.org/wiki/Autologistic%20actor%20attribute%20models | Autologistic actor attribute models (ALAAMs) are a family of statistical models used to model the occurrence of node attributes (individual-level outcomes) in network data. They are frequently used with social network data to model social influence, the process by which connections in a social network influence the outcomes experienced by nodes. The dependent variable can strictly be binary. However, they may be applied to any type of network data that incorporates binary, ordinal or continuous node attributes as dependent variables.
Background
Autologistic actor attributes models (ALAAMs) are a method for social network analysis. They were originally proposed as alteration of Exponential Random Graph Models (ERGMs) to allow for the study of social influence. ERGMs are a family of statistical models for modeling social selection, how ties within a network form on the basis of node attributes and other ties in the network. ALAAMs adapt the structure of ERGM models, but rather than predicting tie formation based on fixed node attributes, they predict node attributes based on fixed ties. This allows for the modeling of social influence processes, for instance how friendship among adolescents (network ties) may influence whether they smoke (node attributes), influences of networks on other health-related practices, and how attitudes or perceived attitudes may change.
ALAAMs are distinct from other models of social influence on networks, such as epidemic/SIR models, because ALAAMs are used for the analysis of cross-sectional data, observed at only a single point in time.
Nodal attributes can be binary, ordinal, or even continuous. Recently, the software of a Melbourne-based research group has incorporated a multilevel approach for ALAAMs in their MPNet software for directed and undirected networks, as well as valued ties (dyadic attributes). The software strictly does not accept missing variables. Cases will need to be deleted if one of their nodal variables is missing. The software is also not able to study ties 'out of the network cluster.' For example: when pupils in classes not only mention friends in their class, but also friends outside of the class(/school).
An alternative to this model to study a nodal attribute as a dependent variable in cross-sectional data is the Multiple Membership model extension for network analysis (can also be extended to make it longitudinal). Unlike ALAAM, it can be used on a continuous dependent variable, is able to handle missingness, can make use of multiple networks (multiplex) and can take ties 'out of the cluster' into account as well.
Definition
ALAAMs, like ERGMs, are part of the Exponential family of probability models. ALAAMs are exponential models that describe, for a network, a joint probability distribution for whether or not each node in the network exhibits a certain node-level attribute.
where is a vector of weights, associated with , the vector of model parameters, and is a normalization constant to ensure that the probabilities of all possible combination of node attributes sum to one.
Estimation
Estimation of model parameters, and evaluation of standard errors (for the purposes of hypothesis testing), is conducted using Markov chain Monte Carlo maximum likelihood estimation (MCMC-MLE), building on approaches such as the Metropolis–Hastings algorithm. Such approaches are required to estimate the model's parameters across an intractable sample space for moderately-size networks. After model estimation, good-of-fit testing, through the sampling of random networks from the fitted model, should be performed to ensure that the model adequately fits the observed data.
ALAAM estimation, while not perfect, has been demonstrated to be relatively robust to partially missing data, due to random sampling or snowball sampling data collection techniques.
Currently, these algorithms for estimating ALAAMs are implemented in the PNet and MPNet software, published by Melnet, a research group at the University of Melbourne
References
Statistical models
Random graphs | Autologistic actor attribute models | [
"Mathematics"
] | 787 | [
"Mathematical relations",
"Graph theory",
"Random graphs"
] |
63,811,074 | https://en.wikipedia.org/wiki/Tochigishiro | Tochigishiro () is a cultivar of hemp grown in Tochigi Prefecture, Japan. It meets international standards of non-narcotic agricultural hemp at about 0.2% THC, reckoned "remarkably low" by Sensi Seeds. It was grown in the early 20th century at Arlington Experimental Farm near the United States capital. The modern variety was developed beginning in 1973 by Kyushu University professor of pharmacy Itsuo Nishioka from seeds "found in southern Japan", and completed 1982 by the Tochigi prefectural government at Tochigi Agricultural Experiment Station in Tochigi-shi. According to a National Institute of Mental Health-affiliated researcher, the strain is missing the enzyme tetrahydrocannabinolic acid synthase that makes most Cannabis capable of producing THC. It is the most widely grown cultivar in Japan in the 21st century, being exempt from prohibition under the Cannabis Control Law, due to its low levels of psychoactive chemicals. Approximately 90% of the hemp grown in Japan is the Tochigishiro variety (as of 2007).
A research report on an experimental plot at Kitami Agricultural Experimental Station on Hokkaido suggests that it may be the most productive known crop for biomass, yielding 52.7 tonnes/ha in a single season. The crop grows about tall.
See also
List of hemp varieties
References
Sources
Hemp agriculture
Cannabis strains | Tochigishiro | [
"Biology"
] | 285 | [
"Cannabis strains",
"Biopiracy"
] |
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