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74,967,374 | https://en.wikipedia.org/wiki/Seismic%20velocity%20structure | Seismic velocity structure is the distribution and variation of seismic wave speeds within Earth's and other planetary bodies' subsurface. It is reflective of subsurface properties such as material composition, density, porosity, and temperature. Geophysicists rely on the analysis and interpretation of the velocity structure to develop refined models of the subsurface geology, which are essential in resource exploration, earthquake seismology, and advancing our understanding of Earth's geological development.
History
The understanding of the Earth's seismic velocity structure has developed significantly since the advent of modern seismology. The invention of the seismogram in the 19th-century catalyzed the systematic study of seismic velocity structure by enabling the recording and analysis of seismic waves.
20th century
The field of seismology achieved significant breakthroughs in the 20th century.In 1909, Andrija Mohorovičić identified a significant boundary within the Earth known as the Mohorovičić discontinuity, which demarcates the transition between the Earth's crust and mantle with a notable increase in seismic wave speeds. This work was furthered by Beno Gutenberg, who identified the boundary at the core-mantle layer in the early to mid-20th century. The 1960s introduction of the World Wide Standardized Seismograph Network dramatically improved the collection and understanding of seismic data, contributing to the broader acceptance of plate tectonics theory by illustrating variations in seismic velocities.
Later, seismic tomography, a technique used to create detailed images of the Earth's interior by analyzing seismic waves, was propelled by the contributions of Keiiti Aki and Adam Dziewonski in the 1970s and 1980s, enabling a deeper understanding of the Earth's velocity structure. Their work laid the foundation for the Preliminary Reference Earth Model in 1981, a significant step toward modeling the Earth's internal velocities. The establishment of the Global Seismic Network in 1984 by Incorporated Research Institutions for Seismology further enhanced seismic monitoring capabilities, continuing the legacy of the WWSSN.
21st century
The advancement in seismic tomography and the expansion of the Global Seismic Network, alongside greater computational power, have enabled more accurate modeling of the Earth's internal velocity structure. Recent progress focuses on the inner core's velocity features and applying methods like ambient noise tomography for improved imaging.
Principle of seismic velocity structure
The study of seismic velocity structure, using the principles of seismic wave propagation, offers critical insights into the Earth's internal structure, material composition, and physical states. Variations in wave speed, influenced by differences in material density and state (solid, liquid, or gas), alter wave paths through refraction and reflection, as described by Snell's Law. P-waves, which can move through all states of matter and provide data on a range of depths, change speed based on the material's properties, such as type, density, and temperature. S-waves, in contrast, are constrained to solids and reveal information about the Earth's rigidity and internal composition, including the discovery of the outer core's liquid state since they cannot pass through it. The study of these waves' travel times and reflections offers a reconstructive view of the Earth's layered velocity structure.
Average velocity structure of planetary bodies
Velocity structure of Earth
Seismic waves traverse the Earth's layers at speeds that differ according to each layer's unique properties, with their velocities shaped by the respective temperature, composition, and pressure. The Earth's structure features distinct seismic discontinuities where these velocities shift abruptly, signifying changes in mineral composition or physical state.
Crust
Average P-wave velocity: 6.0–7.0 km/s (continental); 5.0–7.0 km/s (oceanic)
Average S-wave velocity: 3.5–4.0 km/s
Within the Earth's crust, seismic velocities increase with depth, mainly due to rising pressure, which makes materials denser. The relationship between crustal depth and pressure is direct; as the overlying rock exerts weight, it compacts underlying layers, reduces rock porosity, increases density, and can alter crystalline structures, thus accelerating seismic waves.
Crustal composition varies, affecting seismic velocities. The upper crust typically contains sedimentary rocks with lower velocities (2.0–5.5 km/s), while the lower crust consists of denser basaltic and gabbroic rocks, leading to higher velocities.
Although geothermal gradient, which refers to the increase in temperature with depth in the Earth's interior, can decrease seismic velocities, this effect is usually outweighed by the velocity-boosting impact of increased pressure.
Upper mantle
Average P-wave velocity: 7.5–8.5 km/s
Average S-wave velocity: 4.5–5.0 km/s
Seismic velocity in the upper mantle rises primarily due to increased pressure, similar to the crust but with a more pronounced effect on velocity. Additionally, pressure-induced mineral phase changes, where minerals rearrange their structures, in the upper mantle contribute to this acceleration. For example, olivine transforms into its denser polymorphs, wadsleyite and ringwoodite, at depths of approximately 410 km and 660 km respectively, resulting in a more compact structure that facilitates faster seismic wave propagation in the transition zone.
Lower mantle
Average P-wave velocity: 10–13 km/s
Average S-wave velocity: 5.5–7.0 km/s
In the lower mantle, the rise in seismic velocity is driven by increasing pressure, which is greater here than in the upper layers, resulting in denser rock and faster seismic wave travel. Although thermal effects may lessen seismic velocity by softening the rock, the predominant factor in the lower mantle remains the increase in pressure.
Outer Core
Average P-wave velocity: 8.0–10 km/s
S-waves: Do not propagate as the outer core is liquid
In the outer core, seismic velocity significantly decreases due to its liquid state, which impedes the speed of seismic waves despite the high pressure. This sharp decline is observed at the core-mantle boundary, also referred to as the D'' region or Gutenberg discontinuity.
Furthermore, the reduction in seismic velocity in the outer core suggests the presence of lighter elements like oxygen, silicon, sulfur, and hydrogen, which lower the density of the outer core.
Inner core
Average P-wave velocity: ~11 km/s
Average S-wave velocity: ~3.5 km/s
The solid, high-density composition of the inner core, predominantly iron and nickel, results in increased seismic velocity compared to the liquid outer core. While light elements also present in the inner core modulate this velocity, their impact is relatively contained.
Anisotropy of inner core
The inner core is anisotropic, causing seismic waves to vary in speed depending on their direction of travel. P-waves, in particular, move more quickly along the inner core's rotational axis than across the equatorial plane. This suggests that Earth's rotation affects the alignment of iron crystals during the core's solidification.
There is also evidence suggesting a distinct transition zone ("inner" inner core), with a hypothesized transition zone some 250 to 400 km beneath the inner core boundary (ICB). This is inferred from anomalies in travel times for P-wave that travels through the inner core. This transition zone, perhaps 100 to 200 km thick, may provide insights into the alignment of iron crystals, the distribution of light elements, or Earth's accretion history.
Studying the inner core poses significant challenges for seismologists and geophysicists, given that it accounts for less than 1% of Earth's volume and is difficult for seismic waves to penetrate. Moreover, S-wave detection is challenging due to minimal compressional-shear wave conversion at the boundary and substantial attenuation within the inner core, leaving S-wave velocity uncertain and an area for future research.
Lateral variation of velocity structure
Lateral variation in seismic velocity is a horizontal change in seismic wave speeds across the Earth's crust due to differences in geological structures like rock types, temperature, and fluids presence, affecting seismic wave travel speed. This variation helps delineate tectonic plates and geological features and is key to resource exploration and understanding the Earth's internal heat flow.
Discontinuity
Discontinuities are zones or surfaces within the Earth that lead to abrupt changes in seismic velocity, revealing the composition and demarcating the boundaries between the Earth's layers.
The following are key discontinuities within the Earth:
Mohorovičić discontinuity: the boundary between the crust and the mantle, located approximately 30–50 km below the continental crust and 5–10 km beneath the oceanic crust.
410 km discontinuity: a phase transition where olivine becomes wadsleyite.
520 km discontinuity: a phase transition where wadsleyite becomes ringwoodite.
660 km discontinuity: a phase transition where of ringwoodite to bridgmanite and ferropericlase.
Gutenberg discontinuity: the core-mantle boundary, at approximately 2890 km depth.
Lehmann discontinuity: marking the inner core boundary (ICB), at approximately 5150 km depth.
Velocity structure of the Moon
Knowledge of the Moon's seismic velocity primarily stems from seismic records obtained by Apollo missions' Passive Seismic Experiment (PSE) stations. Between 1969 and 1972, five PSE stations were deployed on the lunar surface, with four operational until 1977. These four stations created a network on the near side of the moon, configured as an equilateral triangle with two stations at one vertex. This network recorded over 13,000 seismic events, and the gathered data remains a subject of ongoing study. The analysis has revealed four moonquake mechanisms: shallow, deep, thermal, and those caused by meteoroid impacts.
Crust
Average P-wave velocity: 5.1–6.8 km/s
Average S-wave velocity: 2.96–3.9 km/s
The seismic velocity on the Moon varies within its roughly 60 km thick crust, presenting a low seismic velocity at the surface. Velocity readings increase from 100 m/s near the surface to 4 km/s at a depth of 5 km and rise to 6 km/s at 25 km depth. At 25 km depth, a discontinuity presence, at which the seismic velocity increases abruptly to 7 km/s. This velocity then stabilizes, reflecting the consistent composition and hydrostatic pressure conditions at greater depths.
Seismic velocities within the Moon's approximately 60 km thick crust exhibit an initial low of 100 m/s at the surface, which escalates to 4 km/s at 5 km depth, and then to 6 km/s at 25 km depth where velocities sharply increase to 7 km/s and stabilize, revealing a consistent composition and pressure conditions in deeper layers.
Surface velocities are low due to the loose, porous nature of the regolith. Deeper, compaction increases velocities, with the region beyond 25 km depth characterized by dense, sealed anorthosite and gabbro layers, suggesting a crust with hydrostatic pressure. The Moon's geothermal gradient minimally reduces velocities by 0.1-0.2 km/s.
Mantle
Average P-wave velocity: 7.7 km/s
Average S-wave velocity: 4.5 km/s
Research into the seismic structure of the Moon's mantle is hampered by the scarcity of data. Analysis of moonquake waveforms suggests that seismic wave velocities in the upper mantle (ranging from 60 to 400 km in depth) exhibit a minor negative gradient, with S-wave speeds decreasing at rates between -6×10−4 to -13×10−4 km/s per kilometer. A decease in P-wave velocities has also been postulated. The data delineates a transition zone between 400 km and 480 km depth, where a noticeable decrement in the velocities of both P- and S-waves occurs.
Uncertainty grows when probing the lower mantle, extending from 480 km to 1100 km beneath the lunar surface. Some studies detect a consistent decline in S-wave transmission, suggesting absorption or scattering phenomena, while other findings indicate that velocities for P- and S-waves may in fact rise.
Temperature increases with depth are believed to be the primary influence behind the observed drop in velocities within the upper mantle, suggesting a mantle heavily regulated by thermal gradients rather than compositional changes. The delineated transition zone implies a division between the chemically distinct upper and lower mantles, possibly explained by an uptick in iron concentration due to high pressure and thermal conditions at depth.
Deeper into the lower mantle, the debate over seismic characteristics continues, with theories of partial melting around the 1000 km depth mark to justify the attenuation of S-wave velocities. This molten state may cause a segregation of materials, resulting in a concentration of magnesium-rich olivine in the lower regions and potentially affecting seismic speeds.
Core
Understanding the seismic velocities within the Moon's core presents challenges due to the limited data available.
Outer core:
Average P-wave velocity: 4 km/s
S-waves: Do not propagate as the outer core is liquid
Inner core:
Average P-wave velocity: 4.4 km/s
Average S-wave velocity: 2.4 km/s
The sharp decline in P-wave velocity at the mantle-core boundary suggests a liquid outer core, transitioning from 7.7 km/s in the mantle to 4 km/s in the outer core. The inability of S-waves to traverse this zone further confirms its fluid nature with molten iron sulphate.
An increase in seismic velocities upon reaching the inner core intimates a transition to a solid phase. The presence of solid iron-nickel alloys, potentially alloyed with lighter elements, is deduced from this increase.
Current geophysical models posit a relatively diminutive Lunar core, with the liquid outer core accounting for 1-3% of the Moon's total mass and the entire core constituting about 15-25% of the lunar mass. While some lunar models suggest the possibility of a core, its existence and characteristics are not unequivocally required by the observed data.
Lateral variation of seismic velocity structure
Crustal velocity also varies laterally, particularly in impact basins, where meteoroid collisions have compacted the substrate, resulting in higher velocities due to reduced porosity.
Lateral variations in the Moon's seismic velocity structure are marked by differences in the crust's physical properties, especially within impact basins. The velocity increases in these regions are attributed to meteoroid impacts, which have compacted the lunar substrate, thereby increasing its density and reducing porosity. This phenomenon has been studied using seismic data from lunar missions, which show that the Moon's crustal structure varies significantly with location, reflecting its complex impact history and internal processes.
Velocity structure of Mars
The investigation into Mars's seismic velocity has primarily relied on models and the data gathered by the InSight mission, which landed on the planet in 2018. By September 30, 2019, InSight had detected 174 seismic events. Before InSight, the Viking 2 lander attempted to collect seismic data in the 1970s, but it captured only a limited number of local events, which did not yield conclusive insights.
Crust
Average P-wave velocity: 3.5–5 km/s
Average S-wave velocity: 2–3 km/s
The crust of Mars, ranging from 10 to 50 km in thickness, exhibits increasing seismic velocity as depth increases, attributable to rising pressure. The upper crust is characterized by low density and high porosity, leading to reduced seismic velocity. Two key discontinuities have been observed: one within the crust at a depth of 5 to 10 km, and another which is likely the crust-mantle boundary, occurring at a depth of 30 to 50 km.
Mantle
Upper mantle:
Average P-wave velocity: 8 km/s
Average S-wave velocity: 4.5 km/s
Lower mantle:
P-wave: 5.5 km/s
S-waves: Not applicable (liquid)
The Martian mantle, composed of iron-rich rocks, facilitates the transmission of seismic waves at high speeds. Research indicates a variation in seismic velocities between depths of 400 and 600 km, where S-wave speeds decrease while P-wave speeds remain constant or increase slightly. This region is known as the Low Velocity Zone (LVZ) in the Martian upper mantle and may be caused by a static layer overlying a convective mantle. The reduction in velocity at the LVZ is likely due to high temperatures and moderate pressures.
Martian mantle research has also identified two discontinuities at depths of approximately 1100 km and 1400 km. These discontinuities suggest phase transitions from olivine to wadsleyite and from wadsleyite to ringwoodite, analogous to the Earth's mantle phase changes at depths of 410 km and 660 km. However, Mars's mantle composition differs from Earth's as it does not have a lower mantle predominated by bridgmanite.
Recent study suggested the presence of a molten lower mantle layer in the Mars which could significantly affect the interpretation of seismic data and our understanding of the planet's thermal history.
Core
Average P-wave velocity: 5 km/s
S-waves: Do not propagate as the outer core is liquid
Scientific evidence suggests that Mars has a substantial liquid core, inferred from S-wave transmission patterns that indicate these waves do not pass through liquid. The core is likely composed of iron and nickel with a significant proportion of lighter elements, inferred from its lower-than-expected density.
The presence of a solid inner core on Mars, comparable to Earth's, is currently the subject of scientific debate. No definitive evidence has yet confirmed the nature of the inner core, leaving its existence and characteristics as topics for further research.
Lateral variation of velocity structure
Lateral variations in the seismic velocity structure of Mars have been revealed by data from the InSight mission, indicating an intricately layered subsurface. InSight's seismic experiments suggest that these variations reflect differences in crustal thickness and composition, potentially caused by volcanic and tectonic processes unique to Mars. Such variations also provide evidence for the presence of a liquid layer above the core, suggesting a complex interplay of thermal and compositional factors affecting the planet's evolution. Further analysis of marsquake data may illuminate the relationship between these lateral variations and the Martian mantle's convective dynamics.
Velocity structure of Enceladus
Research on Enceladus's subsurface composition has provided theoretical velocity profiles in anticipation of future exploratory missions. While Enceladus's interior is poorly understood, scientists agree on a general structure consisting of an outer icy shell, a subsurface ocean, and a rocky core. In a recent study, three models—single core, thick ice, and layered core—were proposed to delineate Enceladus' internal characteristics.
According to these models, seismic velocities are expected to decrease from the ice shell to the ocean, reflecting transitions from porous, fractured ice to a more fluid state. Conversely, velocities are predicted to rise within the solid silicate core, illustrating the stark contrast between the moon's various layers.
Future plan
Seismic exploration of celestial bodies has so far been limited to the Moon and Mars. However, future space missions are set to extend seismic studies to other entities in our solar system.
The proposed Europa Lander Mission, slated for a launch window between 2025 and 2030, will investigate the seismic activity of Jupiter's moon, Europa. This mission plans to deploy the Seismometer to Investigate Ice and Ocean Structure (SIIOS), an instrument designed by the University of Arizona to withstand Europa's harsh, cold, and radiative environment. SIIOS's goal is to provide insight into Europa's icy crust and subterranean ocean.
In conjunction with its Artemis program to the Moon, NASA has also funded initiatives under the Development and Advancement of Lunar Instrumentation (DALI) program. Among these, the Seismometer for a Lunar Network (SLN) project stands out. The SLN aims to facilitate the creation of a lunar seismometer network by integrating seismometers into future lunar landers or rovers. This initiative is part of NASA's broader effort to prepare for continued exploration of the Moon's geology.
Methods
The study of seismic velocity structure is typically conducted through the observation of seismic data coupled with inverse modeling, which involves adjusting a model based on observed data to infer the properties of the Earth's interior. Here are some methods used to study seismic velocity structure:
Applications of velocity structure
Applications of seismic velocity structure encompass a range of fields where understanding the Earth's subsurface is crucial:
Limitation/Uncertainty
S-wave velocity of the inner Earth's core
Investigating Earth's inner core through seismic waves presents significant challenges. Directly observing seismic waves that traverses the inner core is difficult due to weak signal conversion at the core boundaries and high attenuation within the core. Recent techniques like earthquake late-coda correlation, which utilises the later part of a seismogram, provide estimates for the inner core's shear wave velocity but are not without challenges.
Isotropic assumptions
Seismic velocity studies often assume isotropy, treating Earth's subsurface as having uniform properties in all directions. This simplification is practical for analysis but may not be accurate. The inner core and mantle, for example, likely demonstrate anisotropic, or directionally dependent, properties, which can affect the accuracy of seismic interpretations.
Dimensional considerations
Seismic models are frequently one-dimensional, considering changes in Earth's properties with depth but neglecting lateral variations. Although this method eases computation, it fails to account for the planet's complex three-dimensional structure, potentially misleading our understanding of subsurface characteristics.
Non-uniqueness of Inverse Modelling
Seismic velocity structures are inferred through inverse modeling, fitting theoretical models to observed data. However, different models can often explain the same data, leading to non-unique solutions. This issue is compounded when inverse problems are poorly conditioned, where small data variations can suggest drastically different subsurface structures.
Data Limitations for the Moon and Mars Seismic Studies
In contrast to Earth, the seismic datasets for the Moon and Mars are sparse. The Apollo missions deployed a handful of seismometers across the Moon, and Mars's seismic data is limited to the InSight mission's findings. This scarcity restricts the resolution of velocity models for these celestial bodies and introduces greater uncertainty in interpreting their internal structures.
See also
Seismic wave
Seismic tomography
Low-velocity zone
References
Seismology
Geophysics
Geology
Earthquakes | Seismic velocity structure | [
"Physics"
] | 4,762 | [
"Applied and interdisciplinary physics",
"Geophysics"
] |
74,968,571 | https://en.wikipedia.org/wiki/Strychnos%20alkaloids | Strychnos alkaloids are natural products primarily found in the seeds of the strychnine tree (Strychnos nux-vomica) and in the genus catharanthus.
Occurrence
The seeds of the strychnine tree contain up to 2.5% strychnine and brucine.
Representatives
The primary representative of this group of alkaloids are strychnine and brucine. Other notable representatives include vomicin and acuammicin.
Stereochemistry
The naturally occurring strychnos alkaloids are all chiral and sterically uniform. When this article or the scientific literature names one of these alkaloids without adding another name, it actually states:
acuammicine for (-)-acuammicine,
brucine for (-)-brucine,
strychnine for (-)-strychnine and
vomicin for (+)-vomicin.
The bracket expressions represent the sense of rotation of the optical activity of these substances.
Uses and pharmacological action
Strychnine is very toxic. In low doses, it has a stimulating to euphoric effect. A higher dose causes convulsive states. 100 to 130 mg is considered lethal to an adult human.
Brucine is similar to strychnine in structure and physiological effects. It is considered less toxic. Both alkaloids find use as rat poisons and as optically active bases in the enantiomer separation of racemate acids.
History
As early as 1818, strychnine was isolated by Pierre Joseph Pelletier and Joseph Bienaimé Caventou from the Ignatius bean (Strychnos ignatii) extracted. With the structural elucidation of strychnine were engaged especially Hermann Leuchs, Robert Robinson and Heinrich Wieland. Finally, the structure was elucidated by the total synthesis (Robert B. Woodward, 1954).
References
Alkaloids | Strychnos alkaloids | [
"Chemistry"
] | 417 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
74,968,763 | https://en.wikipedia.org/wiki/Reconstruction%20of%20attosecond%20beating%20by%20interference%20of%20two-photon%20transitions | Reconstruction of attosecond beating by interference of two-photon transitions, more commonly known as RABBITT or RABBIT for short, is a widely used technique for obtaining the relative phase and amplitude of attosecond pulses. This technique involves the interference of two-photon interband transitions in solids. It is especially suited for diagnostics on the temporal structure of XUV pulses. The reconstruction of attosecond beating by interference of two-photon transitions is a valuable tool for studying ultrafast processes in materials and can provide insight into the dynamics of electrons in solids.
History
RABBITT was invented by Pierre Agostini, Harm Geert Muller and colleagues in 2001.
References
Experimental physics
Ultrafast spectroscopy | Reconstruction of attosecond beating by interference of two-photon transitions | [
"Physics"
] | 142 | [
"Experimental physics"
] |
74,969,457 | https://en.wikipedia.org/wiki/Areca%20alkaloids | Areca alkaloids are a group of piperidine alkaloids found in the areca nut, the seeds of the areca palm (Areca catechu).
Occurrence
Areca alkaloids are isolated from the areca nut, which are hemispherical seeds and are approximately 3 cm in size. Areca nuts are cultivated in India and East Asia.
Representative
The main alkaloid is arecoline, which accounts for over 50% of the total alkaloid content. Other representatives include arecaidine, guvacoline, and guvacine.
The total alkaloid content of the nuts increases during ripening and decreases upon subsequent drying. A roasting of dried nuts increases the proportion of arecoline in the total alkaloid content.
Properties
Arecolin is a potent parasympathomimetic that enhances salivary and sweat secretion and stimulates intestinal activity. The vermifuge function of areca preparations is used today only in veterinary medicine. Traditionally, areca nut has been used as an aphrodisiac, anorectic, digestive stimulant, and diuretic, as well as in the treatment of asthma, cough, dermatitis, fainting, glaucoma, erectile dysfunction, worm diseases, leprosy, toothache, and vaginal discharge, as well as to constrict the vagina.
Areca nuts are typically chewed with lime and leaves of betel pepper, especially in East Asia (known as "sirih pinang"). This practice stimulates the nervous system in a manner akin to tobacco.
References
Alkaloids | Areca alkaloids | [
"Chemistry"
] | 344 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
74,970,969 | https://en.wikipedia.org/wiki/Dawson%20structure | The Dawson structure is a well-known structural motif for heteropoly acids. The Dawson structure can be viewed as the fusion of two defect Keggin structure, fragments with three missing octahedra. As in Keggin structures, the Dawson structure has an oxyanion at its core. Unlike Keggin structures, there are two such anions, one at each side of the ellipsoidal anion. An example is , which can also be described as .
Commonly, Dawson structures feature phosphate as the central oxyanions. When the Keggin anion is allowed to stand in aqueous solution, it converts to .
References
Cluster chemistry
Heteropoly acids
Anions | Dawson structure | [
"Physics",
"Chemistry"
] | 145 | [
"Matter",
"Acids",
"Anions",
"Heteropoly acids",
"Cluster chemistry",
"Organometallic chemistry",
"Ions"
] |
74,971,179 | https://en.wikipedia.org/wiki/Raphopoda | Raphopoda is a grouping of heterotrophic protists. It contains the heterotroph organisms within class Raphidomonadea, classified as two orders: Commatiida, comprised by the sole genus of flagellates Commation, and Actinophryida, an order of heliozoa, amoebae with stiff specialized pseudopodia called axopodia.
References
Taxa described in 2013
Ochrophyta | Raphopoda | [
"Biology"
] | 95 | [
"Ochrophyta",
"Algae"
] |
74,972,365 | https://en.wikipedia.org/wiki/Transition%20metal%20phosphate%20complex | Transition metal phosphate complexes are coordination complexes with one or more phosphate ligands. Phosphate binds to metals through one, two, three, or all four oxygen atoms. The bidentate coordination mode is common. The second and third pKa's of phosphoric acid, pKa2 and pKa3, are 7.2 and 12.37, respectively. It follows that are sufficiently basic to serve as ligands. The examples below confirm this expectation. Molecular metal phosphate complexes have no or few applications.
Examples
Bidentate, chelating: One example is [Co(ethylenediamine)2(PO4)].
Bis-Bidentate: (tetraamine = )
Bidentate, bridging: Phosphate, like carboxylate and sulfate, is well suited to span metal-metal bonds. This bonding mode is illustrated by , which features a Mo-Mo triple bond. Related [Pt(III)]2 complexes have been reported.
Tridentate, bridging. Several triangulo clusters feature a capping phosphate ligand, e.g. .
Encapsulated: In phosphotungstic acid, all four oxygen atoms of phosphate are bonded to metals.
Other transition metal phosphates
Aside from molecular metal phosphate complexes, the topic of this article, many or most transition metal phosphates are nonmolecular, being coordination polymers or dense ternary or quaternary phases. Iron(III) phosphate, contemplated as a cathode material for batteries, is one example. Vanadyl phosphate () is a commercial catalyst for oxidation reactions. Many metal phosphates occur as minerals.
Di- and polyphosphates
Phosphates exist in many condensed oligomeric forms. Many of these derivatives function as ligands for metal ions. Pyrophosphate () and trimetaphosphate () have been particularly studied. They typically function as bi- and tridentate ligands.
References
Ligands
Coordination chemistry
Phosphates | Transition metal phosphate complex | [
"Chemistry"
] | 407 | [
"Ligands",
"Coordination chemistry",
"Phosphates",
"Salts"
] |
74,972,434 | https://en.wikipedia.org/wiki/Apocynaceae%20alkaloids | Apocynaceae alkaloids are natural products found in the plant family of the dogbane family (Apocynaceae).
Occurrence
The alkaloid tabernanthin is found in Tabernaemontana laurifolia. The alkaloids voacangin and voacristin were isolated from Voacanga africana.
Representatives
Representatives include tabernanthine, voacangine and voacristine.
Uses
Plant parts of Voacanga africana are utilized by African natives for various purposes, including as hallucinogens, in cultic ceremonies, and as aphrodisiacs.
Ethnomedicinal use
A decoction made from the stem or root bark is employed for the treatment of mental disorders and as an analgesic. The sap is applied to cavities in teeth. In southeastern Nigeria, Voacanga africana is an integral part of numerous healing rituals.
References
Alkaloids | Apocynaceae alkaloids | [
"Chemistry"
] | 193 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
55,035,238 | https://en.wikipedia.org/wiki/Panamesine | Panamesine (; developmental code name EMD-57455) is a sigma receptor antagonist that was under development by Merck as a potential antipsychotic for the treatment of schizophrenia in the 1990s but was never marketed. It is a selective antagonist of both sigma receptor subtypes, the σ1 and σ2 receptors (IC50 = 6 nM). In addition, the major metabolite of the drug, EMD-59983, has high affinity for the sigma receptors (IC50 = 24 nM) and the dopamine D2 (IC50 = 23 nM) and D3 receptors, with potent antidopaminergic activity. Panamesine reached phase II clinical trials for schizophrenia prior to the discontinuation of its development.
See also
BMY-14802
Eliprodil
Rimcazole
References
Abandoned drugs
Tertiary alcohols
Antipsychotics
Benzodioxoles
D2 antagonists
D3 antagonists
Ketones
Oxazolidines
4-Phenylpiperidines
Sigma antagonists | Panamesine | [
"Chemistry"
] | 220 | [
"Ketones",
"Functional groups",
"Drug safety",
"Abandoned drugs"
] |
55,036,262 | https://en.wikipedia.org/wiki/Chris%20Sherwin | Christopher M. Sherwin (1 December 1962 – 18 July 2017) was an English veterinary scientist and senior research fellow at the University of Bristol Veterinary School in Lower Langford, Somerset. He specialised in applied ethology, the study of the behaviour of animals in the context of their interactions with humans, and of how to balance the animals' needs with the demands placed on them by humans.
Sherwin became known for his work on the welfare of animals in zoos, farms and laboratories, and in particular for his research into the behaviour of laboratory mice. He created and chaired the Animal Ethics Committee of the International Society for Applied Ethology, and in 2003 was the lead author of its ethical guidelines. He also served as secretary of the Ethical Committee of the Association for the Study of Animal Behaviour. A colleague at Bristol described Sherwin as a "stalwart advocate for animals and their welfare". In 2019 the RSPCA posthumously awarded Sherwin a Special Recognition Award: according to the Head of the RSPCA's Research Animals Department, "Chris Sherwin’s work influenced and assisted all of the RSPCA science departments, which deal with wildlife, research, companion and farmed animals".
Early life and education
Sherwin was born in Bradford, England, and spent several years in Australia, where he earned his BSc in veterinary biology from Murdoch University in Perth. In 1987 he obtained his PhD, also from Murdoch University, for a thesis entitled Shading behaviour in sheep: The influence of social and thermal factors.
Career
Research overview
Sherwin became a junior research fellow at the University of New England in Armidale, New South Wales, where he wrote about electronic tags and ear damage in pigs before returning to England in 1990. That year he joined the Animal Welfare and Behaviour group at the University of Bristol Veterinary School to work on enriched housing for laying hens. Sherwin worked at Bristol until he retired in 2012. During his two decades there, he became known for his research into improving the housing and husbandry of captive animals, and for his work on developing ethical guidelines for animal use. He studied poultry in commercial facilities, mice in laboratories, elephants in zoos, insect consciousness, and the use of video to record farm animals' behaviour.
Poultry and laboratory birds
Sherwin's studies included examining the behaviour of birds on farms and in laboratories. He wrote about housing for poultry used in meat and egg production. Between 1998 and 2001 he published 11 papers on turkeys, which included examining the effect of lighting on their welfare; his research suggested that turkeys prefer brighter lights than those in commercial facilities. In the early 2000s, he was a member of the European Council's Working Group for Birds, which wrote provisions for birds for the European Convention for the Protection of Vertebrate Animals used for Experimental and Other Scientific Purposes. In a study for the RSPCA's "Freedom Food" label in 2009, he led a team from Bristol University that investigated stocking densities of hens used for eggs. In 2010, Sherwin found a high incidence of broken bones in hens housed in a type of cage that was banned in the European Union soon afterwards.
Elephants in zoos
From 2005 to 2007 Sherwin was part of a team funded by the Department for Environment, Food and Rural Affairs (Defra), the RSPCA, BIAZA, and IFAW to write a report concerning captive elephants: The Welfare, Housing and Husbandry of Elephants in UK Zoos (2008), about the 77 elephants then kept in 13 British zoos. Sherwin told the BBC that almost half the elephants engaged in behaviour not seen in the wild, such as pacing, retracing their steps, and repeatedly swaying their trunks, which "almost certainly indicates they're in an environment which is inappropriate for their needs". According to the report, 38 percent of the elephants the team examined performed these stereotypies for over one percent of the time during the day, and nearly half did so at night; during one 24-hour period, one elephant stereotyped over 60 percent of the time. In Sherwin's view, elephants could be kept in zoos with the correct housing and care, but not in the numbers seen at that time.
Invertebrate pain
Another of Sherwin's research interests was the complexity of invertebrate behaviour and their capacity to suffer pain. He told Discovery News in 2009 that whether invertebrates experience pain was "fundamental" to the laws that protect animals and regulate their use. Mike Mendl, a colleague of Sherwin's, wrote that Sherwin anticipated the interest in insect emotion and consciousness by over a decade. According to Jonathan Balcombe, Sherwin challenged the traditional view of the insect as a "spineless, pre-programmed automaton".
Sherwin reasoned that insects had preferences, habits, and memories, and could experience suffering as a "negative mental state". That insects have different nervous systems and might perceive pain differently from vertebrates does not mean they lack consciousness. When deciding whether an animal can suffer, he wrote in 2001, we compare its responses to those of evolutionarily higher animals, an argument by analogy, and find that invertebrates "often behave in a strikingly analogous manner to vertebrates". He told a conference in 2000: If a chimp pulls its hand away after an electric shock, we say she presumably must have felt an analogous subjective experience to what we call pain. But cockroaches, slugs and snails—which are not protected by legislation—also reacted in the same way, while tests on flies showed they could associate a smell with receiving an electric shock. If it is a chimp we say it feels pain, if a fly we don't. Why?
Laboratory mice
Sherwin's most influential research was on the behaviour and welfare of laboratory mice. In one highly cited study, published in 1998, he built a device that allowed five mice to leave their cages—by pressing levers to open the door—for a loop that they could run around, a series of tunnels, or a wheel. Over time, they had to press the lever more often, up to 80 times, to gain access. Of the three options, the loop was the least preferred, and the wheel was "least affected by increasing the cost of access". As a result of that research, Sherwin was awarded a Universities Federation for Animal Welfare (UFAW) Hume Research Fellowship in 2001.
He went on to conduct extensive studies on laboratory cage design, showing that mice kept in ordinary cages chose to drink more of an anxiety-reducing drug than mice housed in larger cages with nesting material, a nest box, and a running wheel, where they could burrow and be with other mice. He trained mice to open a lever to access cages with more space, varying how often the lever had to be pressed, and found that more space was something they were willing to work for. He found that cage colour affected mouse welfare, including body weight; the mice liked white cages most and red least. In another study, he demonstrated that mice need to engage in burrowing behaviour. Laboratory mice spent the same amount of time burrowing whether or not they were supplied with ready-made burrows. Sherwin used burrows constructed by the same mouse in an earlier part of the experiment, thereby addressing the argument that the mouse continued to burrow only because the ready-made burrows were inadequate.
Housing and husbandry
Sherwin wrote in 2004 that the behaviour and health of laboratory animals given standard housing and care are frequently abnormal, which may reduce the value of the data obtained from them. The RSPCA quoted from his paper in a brochure discussing corporate social responsibility and "the 3Rs". In 2007 he argued, in a letter to Nature, that it was good science to include details about the handling and housing of laboratory animals in published papers, because factors such as cage size and flooring can influence metabolism, temperature, blood pressure and feeding behaviour.
Other work
From 1998 to 2001 Sherwin sat on the Council of the International Society for Applied Ethology (ISAE). He later chaired the ISAE's Animal Ethics Committee, and was the lead author in 2003 of its ethical guidelines. In 2006 he was the lead organizer of the 40th International Congress of the ISAE at Bristol. He also served as secretary of the Ethical Committee of the Association for the Study of Animal Behaviour, and sat on the editorial board of the journal Animal Sentience.
He was a member of the Joint Working Group on Refinement (JWGR), set up by the British Veterinary Association's Animal Welfare Foundation, FRAME, the RSPCA and UFAW, which produced a report on laboratory birds in 2001.
In 2005 he sat on the European Food Safety Authority's (EFSA) working group on laboratory animals. Sherwin's team, led by Donald Broom, addressed the protection of invertebrates and animal fetuses. The assessment was adopted by the EFSA's Panel on Animal Health and Welfare in November 2005, which decided that animal fetuses should be given anaesthesia and analgesia for procedures that would cause pain in the newborn of the same species.
After his retirement, Sherwin became an editor on Wikipedia, where he wrote nearly fifty articles.
Selected works
Sherwin published over 62 works, including:
Sherwin, Chris M. (2002). "Comfortable quarters for mice in research institutions". In V. Reinhardt & A. Reinhardt (eds.). Comfortable Quarters for Laboratory Animals, 9th edition. Washington, DC: Animal Welfare Institute, pp. 6–7.
Sherwin, C. M. (2005). "Turkeys: Behaviour, Management and Well-Being", in Wilson G. Pond and Alan W. Bell (eds.). Encyclopedia of Animal Science. New York: Marcel Dekker, pp. 847–852.
Sherwin, Chris (2010). "The Husbandry and Welfare of Non-Traditional Laboratory Rodents", in R. Hubrecht and J. Kirkwood (eds.). The UFAW Handbook on the Care and Management of Laboratory and Other Research Animals, 8th edition. Oxford: Wiley-Blackwell, pp. 359–369.
Notes
References
1962 births
2017 deaths
Academics of the University of Bristol
British animal welfare scholars
English biologists
English emigrants to Australia
Ethologists
Murdoch University alumni
Scientists from Bradford
Veterinary scientists
Academic staff of the University of New England (Australia) | Chris Sherwin | [
"Biology"
] | 2,145 | [
"Ethology",
"Behavior",
"Ethologists"
] |
55,036,321 | https://en.wikipedia.org/wiki/Edward%20A.%20Murphy%20%28chemist%29 | Edward Arthur Murphy was a Dunlop researcher credited with the invention of latex foam, first marketed as Dunlopillo.
Career
Murphy worked for Dunlop in Birmingham, UK. He is listed as an inventor on more than 40 patents.
Awards and Recognitions
1929 - Invented Dunlopillo latex, used as pad seats in public trams, trains, trolley buses and cockpits
1931 - Invented first latex mattress
1949 - Colwyn medal
1966 - Charles Goodyear Medal from the ACS Rubber Division
References
Polymer scientists and engineers | Edward A. Murphy (chemist) | [
"Chemistry",
"Materials_science"
] | 102 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
55,037,836 | https://en.wikipedia.org/wiki/Expo%20for%20Design%2C%20Innovation%20%26%20Technology | Expo for Design, Innovation & Technology (EDIT) is a 10-day festival launched by the Canadian Design Exchange (DX) in partnership with the United Nations Development Programme (UNDP). It is also supported by the Government of Ontario and its Ontario150 Program. The festival has received a $1.75 million investment from the Government of Ontario in 2017. The festival focuses on design, innovation and technology solutions and highlights the potential that the design industry has to solve issues on a global scale. The first annual festival took place in Toronto from September 28 to October 8, 2017, with a capacity of approximately 100,000 visitors.
The overall theme to EDIT was "Prosperity For All". It was inspired by the United Nations Development Program's (UNDP) Global Goals for Sustainable Development. The theme was portrayed through an art installation by designer Bruce Man, so co-founded Massive Change Network. It featured large black and white images of global conflict like pollution, genocide, and terrorism.
References
Canadian design
Design events
2017 festivals in North America
Festivals in Toronto
150th anniversary of Canada
2017 in Toronto | Expo for Design, Innovation & Technology | [
"Engineering"
] | 223 | [
"Design",
"Design events"
] |
55,037,939 | https://en.wikipedia.org/wiki/Tudor%20Ratiu | Tudor Stefan Rațiu (born March 18, 1950) is a Romanian-American mathematician who has made contributions to geometric mechanics and dynamical systems theory.
Education
Rațiu was born in Timișoara. His father, Mircea Ratiu, an engineer, was the younger brother of Ion Rațiu, a well-known Romanian politician, while his mother, Rodica Bucur, was a piano professor at the Conservatory of Music in Timișoara. Ratiu did his undergraduate studies at the Politehnica University of Timișoara, completing his B.Sc. in 1973 and his M.S. in 1974.
After moving to the United States, he completed his Ph.D. degree at the University of California, Berkeley in 1980; his dissertation, written under the supervision of Jerrold E. Marsden, was titled Euler-Poisson Equations on Lie Algebras.
Career
From 1980 to 1983 Ratiu was a T. H. Hildebrandt Research Assistant Professor at the University of Michigan, after which he became an Associate Professor of Mathematics at the University of Arizona. In 1987 he moved to the University of California, Santa Cruz, where he became a Professor of Mathematics in 1988.
In 1998 Ratiu moved to the École Polytechnique Fédérale de Lausanne, where he was a professor until 2015. In 2014–15, he was a Professor of Mathematics at the Skolkovo Institute of Science and Technology in Russia. Since 2016 he is a professor at Shanghai Jiao Tong University in China.
Ratiu received a Sloan Research Fellowship in 1980, and he became a fellow of the American Mathematical Society in 2012.
Publications
References
External links
1950 births
Living people
Scientists from Timișoara
20th-century Romanian mathematicians
21st-century Romanian mathematicians
Politehnica University of Timișoara alumni
University of California, Berkeley alumni
University of Michigan faculty
University of Arizona faculty
University of California, Santa Cruz faculty
Academic staff of the École Polytechnique Fédérale de Lausanne
Academic staff of Shanghai Jiao Tong University
Dynamical systems theorists
Fellows of the American Mathematical Society
Sloan Research Fellows | Tudor Ratiu | [
"Mathematics"
] | 419 | [
"Dynamical systems theorists",
"Dynamical systems"
] |
55,038,237 | https://en.wikipedia.org/wiki/Cloniprazepam | Cloniprazepam is a benzodiazepine derivative and a prodrug of clonazepam, 7-aminoclonazepam, and other metabolites.
Some of the minor metabolites include 3-hydroxyclonazepam and 6-hydroxyclonazepam, 3-hydroxycloniprazepam and ketocloniprazepam with ketone group formed where 3-hydroxy group was.
It is a designer drug and an NPS (short for "new psychoactive substance"). At the end of 2017, cloniprazepam was an uncontrolled substance in most of the countries.
See also
Flutoprazepam
Ro05-4082
List of designer drugs
List of benzodiazepines
List of benzodiazepine designer drugs
References
External links
https://www.unodc.org/LSS/Substance/Details/d115de07-ab8f-4454-a8f7-3ea15f4a0748
https://web.archive.org/web/20160623204002/http://nsddb.eu/substance/590/
Anticonvulsants
Anxiolytics
Nitrobenzodiazepines
Designer drugs
GABAA receptor positive allosteric modulators
Prodrugs
2-Chlorophenyl compounds
Cyclopropyl compounds | Cloniprazepam | [
"Chemistry"
] | 315 | [
"Chemicals in medicine",
"Prodrugs"
] |
55,039,969 | https://en.wikipedia.org/wiki/Contralateral%20brain | The contralateral organization of the forebrain (Latin: contra‚ against; latus‚ side; lateral‚ sided) is the property that the hemispheres of the cerebrum and the thalamus represent mainly the contralateral side of the body. Consequently, the left side of the forebrain mostly represents the right side of the body, and the right side of the brain primarily represents the left side of the body. The contralateral organization involves both executive and sensory functions (e.g., a left-sided brain lesion may cause a right-sided hemiplegia). The contralateral organization is only present in vertebrates.
A number of theories have been put forward to explain this phenomenon, but none are generally accepted. These include, among others, Cajal's visual map theory, different topological approaches, the somatic twist theory and the axial twist theory.
Anatomy
Anatomically, the contralateral organization is manifested by major decussations (based on the Latin notation for ten, 'deca,' as an uppercase 'X') and chiasmas (after the Greek uppercase letter 'Χ,' chi). A decussation denotes a crossing of bundles of axonal fibres inside the central nervous system. Due to decussations the efferent connections of the cerebrum to the basal ganglia, the cerebellum and the spine are crossed; and the afferent connections from the spine, the cerebellum and the pons to the thalamus are crossed. Thus, motor, somatosensory, auditory, and visual primary regions in the forebrain predominantly represent the contralateral side of the body.
Two of the cranial nerves show chiasmas: (1) the chiasma of the optic tract (i.e., cranial nerve II), which originates from the eyes and inserts on the optic tectum of the midbrain; and (2) the trochlear nerve (i.e., cranial nerve IV), which originates in the ventral midbrain and innervates one of the six muscles that rotate the eye (i.e., the superior oblique muscle). The oculomotor nerve (cranial nerve III) crosses the midline before leaving the central nervous system (i.e. it decussates rather than chiasmates).
The contralateral organization is incomplete
Although the forebrain of all vertebrates shows a contralateral organization, this contralaterality is by no means complete. Some of these exceptions are worth mentioning:
Olfaction (i.e., smelling sense) is a noteworthy exception. Each olfactory lobe connects to the ipsilateral (same-side) centers of the frontal cerebrum.
In chondrichthyans (e.g., sharks and skates), the thalamus does not retrieve a branch from the optic tract but only from the contralateral optic tectum, so that the optic path decussates twice, and the forebrain represents the ipsilateral (same-side) eye.
In large brains (e.g., humans, elephants and whales), some functions tend to be strongly lateralized. For example, the language regions (i.e., Broca's and Wernicke's area) are situated in the left hemisphere of most humans.
Most afferent and efferent connections of the forebrain have bilateral components, especially outside the primary sensory and motor regions. As a result, a hemiplegia that is acquired at very young age can sometimes be completely compensated over time.
Theories
According to current understanding, the contralateral organization is due to an axial twist (explained below). A number of other explanations have been published, the most popular of which is the visual map theory (explained below). A short review of existing hypotheses is given by reference. A popular-science video explains these theories in brief.
The Visual Map Theory and the Axial Twist Theory have been formulated in detail and can be regarded as scientific theories, and are explained in detail below.
Other hypotheses tend to explain specific aspects of the phenomenon. One proposes that crossing generally provides better geometrical mapping. According to another view, the crossing is a coincidence that has been conserved by parcellation. A third hypothesis proposes that the crossing results directly from optical inversion on the retina of the eye.
An old notion, first worked out by Jacques Loeb, is that the contralateral organisation might have an advantage for motor control,
but simulations by Valentino Braitenberg have shown that both ipsi- and contralateral connections are of major importance for control.
Further studies have asked if there is a topological
or functional advantage of the decussations.
Visual map theory
The visual map theory was published by the famous neuroscientist and pioneer Santiago Ramón y Cajal (1898). According to this theory, the function of the optic chiasm is to repair the retinal field image on the visual cortex. The pupil in the vertebrates’ eyes inverts the image on the retina, so that the visual periphery projects to the medial side of the retina. By the chiasmatic crossing, the visual periphery is again on the outside, if one assumes that the retinal map is faithfully maintained throughout the optic tract.
The theory has a number of weaknesses. For example, the visual tracts spiral their way from the thalamic LGN to the visual cortex. (See figure; this path is known as the optic radiation.) As a result, the retinal map shows the visual periphery on the medial side. However, the central objective of the theory was to obtain a precise, faithful visual map with the medial field projecting to the medial sides of the visual cortex.
Axial twist
Two twist hypotheses have been proposed independently: the axial twist by de Marc Lussanet and Jan Osse and the somatic twist by Marcel Kinsbourne. Both of them propose that the rostral part of the head, including the forebrain, is in fact effectively completely turned around. As a consequence, the left and right in the brain are reversed, but also anterior (frontal) and posterior (back / occipital). Whereas the somatic twist hypothesis focuses purely on the morphological phenomenon of the inversions of the forebrain, the axial twist theory also addresses the development and the evolution.
The scientific method has been used on the axial twist theory to generate empirically testable predictions, all of which were confirmed, albeit in a work by the first author of the theory.
Axial twist theory
The axial twist theory was designed to explain how the pattern of contralateral organization, decussations and chiasmas develops, and why this pattern is so evolutionarily stable, having no known exceptions throughout the 500 million years of vertebrate evolution. According to the theory, the contralateral organization develops as follows: The early embryo is turned onto its left side, such that its left is turned to the yolk and its right is turned away from the yolk. This asymmetric orientation is compensated by asymmetric growth, to regain superficial bilateral symmetry. The anterior head region turns to the left, as shown in the schema. The forebrain is not a superficial structure, but it is so intimately associated with superficial body structures that it turns along with the anterior head. These structures will later form the eyes, nostrils and mouth.
The body behind the head compensates the asymmetric body orientation in the opposite direction, by turning to the right. (See schema.) Due to these oppositely directed compensations of the anterior head and the rest of the body, the animal becomes twisted.
The optic tract grows from the retina to the optic tectum. Because dorsal and ventral are inverted in the anterior head region, the tracts grow at first toward the ventral side, to meet in the midline to form a chiasma. Since the optic tectum lies on the dorsal midbrain, each tract then continues dorsally to the contralateral optic tectum.
The heart and bowels are internal organs with no strong integration in external body structures, so there is no evolutionary pressure to make them turn in a similar way. Rather, these organs retain their original asymmetric orientation in the body.
The axial twist hypothesis predicts that small asymmetries of the face and brain—as well as those found in the opposite direction in the trunk—remain into adulthood.
Comparing inversion, somatic twist and axial twist
The idea of a somatic twist was inspired by the dorsoventral inversion hypothesis; and was proposed by Marcel Kinsbourne.
According to the dorsoventral inversion hypothesis, an ancestral deuterostome turned on its back. As a result, vertebrates have a dorsal nervous system, whereas protostomes have a ventral one. According to the somatic twist hypothesis, not the entire animal turned on its back but just the somatic part—i.e., everything behind the eyes, mouth and nostrils, including the forebrain.
The somatic twist hypothesis was proposed as an improvement to the inversion hypothesis, and thus has a much wider explanatory power than its predecessor, but is also more complicated. It not only explains the inversion of the body but additionally the contralateral forebrain. It does not explain, however, how the twist might develop in the vertebrate embryo, nor does it address the possible evolution.
The axial twist theory was proposed independently. In addition to providing rationale for the inverted body and the contralateral forebrain, it explains why the heart and bowels are asymmetric. It is the only one of the three theories that is supported by evidence from embryological growth.
Evolution
A remarkable property of the contralateral organization is that it is present in every vertebrate. Even the most distant clades—agnathans—possess an optic chiasma, and even the skull impressions of early vertebrates from the Ordovician show the presence of an optic chiasma: this idea was worked out by Kinsbourne.
There is molecular evidence for the inversion hypothesis in almost all groups of deuterostomes. It is not known, however, what exactly was the selective pressure that caused the inversion. Twisting and asymmetric development are well known from other deuterostomes—such as Hemichordata, Echinodermata, Cephalochordata and Tunicata. Turning toward the side or upside-down also occurs frequently in these clades (e.g. sea stars which turn their mouth downwards after the larva has briefly settled with the mouth turned up, or the adult lancelet which buries obliquely with its mouth turned up, or many fish which tend to turn around when feeding from the water surface).
Developmental malformations
In holoprosencephaly, the hemispheres of the cerebrum or part of it are not aligned on the left and right side but only on the frontal and occipital sides of the skull, and the head usually remains very small. According to the axial twist hypothesis, this represents an extreme case of Yakovlevian torque, and
may occur when the cerebrum does not turn during early embryology.
Cephalopagus or janiceps twins are conjoined twins who are born with two faces, one on either side of the head. These twins have two brains and two spinal cords, but these are located on the left and the right side of the body. According to the axial twist hypothesis, the two nervous systems could not turn due to the complex configuration of the body and therefore remained on either side.
See also
Brain asymmetry
Lateralization of brain function
References
Animal developmental biology
Evolutionary biology
Cerebrum
Biology theories | Contralateral brain | [
"Biology"
] | 2,446 | [
"Evolutionary biology",
"Biology theories"
] |
55,040,042 | https://en.wikipedia.org/wiki/IPhone%208 | The iPhone 8 and iPhone 8 Plus are smartphones developed and marketed by Apple Inc. They are the eleventh generation of the iPhone. The iPhone 8 was released on September 22, 2017, succeeding the iPhone 7 and iPhone 7 Plus, respectively.
The designs of the iPhone 8 and 8 Plus are largely similar to that of their predecessors except for the addition of a glass back. The iPhone 8 and 8 Plus were the final flagship iPhone models to feature the home button and Touch ID. Notable changes include the removal of the rose gold and jet black color variants, addition of inductive charging, a faster processor, and improved cameras and displays. The iPhone 8 and 8 Plus share most of their internal hardware with the iPhone X.
The iPhone 8 and 8 Plus were discontinued as of February 2020, having sold 86.3 million units worldwide, making them one of the best-selling smartphones of all time. They initially shipped with iOS 11 and supported up to iOS 16, and do not support iOS 17.
The second and third generations of the entry level iPhone SE retain the iPhone 8's exterior dimensions and Touch ID, with upgraded hardware.
History
Apple invited the press to a media event at the Steve Jobs Theater in the Apple Park campus on September 12, 2017. The iPhone 8 and iPhone 8 Plus were announced at that event, and released on September 22, 2017.
On April 9, 2018, Apple introduced an iPhone 8 with a red color finish and a black front, in support of their partnership with Product Red and their AIDS fundraising campaign.
In November 2018, just over a year from initial release, Apple started selling refurbished iPhone 8 models starting at $499. The price was lowered to US$319. Refurbished iPhone 8 Plus models were available starting at $599. The price was also subsequently lowered to US$469 and later to $359.
On April 15, 2020, Apple announced the second-generation iPhone SE and discontinued the iPhone 8 and 8 Plus, which share the external form factor but has upgraded internals including an A13 Bionic processor. On March 8, 2022, Apple announced the third-generation iPhone SE with the same exterior dimensions, but with an upgraded camera and Apple's A15 processor.
Specifications
Hardware
Display
The iPhone 8 and 8 Plus retain the Retina HD Display found in the iPhone 7, but they now feature True Tone technology, allowing for automatic screen adjustments based on surrounding ambient lighting. They can play HDR10 and Dolby Vision content despite not having an HDR-ready display, done by down-converting the HDR content to fit the display while still having some enhancements to dynamic range, contrast, and wide color gamut compared to standard content.
Camera
The iPhone 8 and 8 Plus feature a 12 MP camera with autofocus, f/1.8 aperture and optical image stabilization capable of capturing 4K video at 24, 30, or 60 frames per second, or 1080p video at 30, 60, 120 or 240 frames per second, and a Quad LED True Tone Flash with Slow Sync. The Slow Sync flash, 4K 60fps, and 1080p 240 fps options are new features for the 8 and 8 Plus, over the options available on the iPhone 7 and 7 Plus.
The iPhone 8 Plus, like the iPhone 7 Plus, adds a second, telephoto, lens. A new AI-driven option is available for the iPhone 8 Plus, called Portrait Lighting--making use of the more capable image signal processor in the A11 SoC.
Both models have a 7 MP front camera with an f/2.2 aperture capable of capturing 1080p video at 30 frames per second and 720p video at 24 frames per second, along with face detection and high-dynamic range.
The iPhone 8 and 8 Plus record videos with single channel audio (mono).
Still photos with 6.5 megapixels (3412×1920) can be captured during video recording.
Chipset
The iPhone 8 and 8 Plus contain the Apple A11 Bionic system-on-chip, a hexa-core processor that the company says features two performance cores that are 25% faster than those found in the iPhone 7's A10 processor and four efficiency cores that are 70% faster than those in the prior model. The phones also feature an Apple-designed graphics processing unit 30% faster than prior units, with the same level of performance as the A10 at half the power.
Other
The phones have glass backs instead of the complete aluminum housing found on prior models, enabling the use of Qi inductive charging. The phones are rated IP67 for water resistance and dust resistance.
Both models come with 64, 128, and 256 gigabytes storage options, and are offered in silver, gold, or Space Gray color options. A Product Red special edition version in red with a black front was released on April 9, 2018. The iPhone 8 and 8 Plus were the last iPhones with white front in Silver and Gold colors.
In addition to Qi wireless charging, the iPhone 8 also supports wired charging using Apple's proprietary Lightning connector. It can fast-charge from a charger providing USB Power Delivery combined with a special USB-C to Lightning adapter cable supporting fast charging.
The iPhone 8 has a 6 out of 10 reparability score from iFixit, mainly due to the use of excessive glue for the back glass.
Software
Both the iPhone 8 and 8 Plus were supplied with iOS 11 on launch, and support iOS 12, iOS 13, iOS 14, iOS 15 and iOS 16. Apple announced that the iPhone 8 and 8 Plus, as well as the iPhone X, would not support iOS 17 due to hardware limitations. However, the devices still receive security updates.
Reception
Reception of the phones was generally positive, with reviewers praising the addition of inductive charging, fast charge capability, and the new Apple A11 processor, while criticizing the aging design that was introduced with the iPhone 6 and iPhone 6 Plus in 2014.
Samuel Axon of Ars Technica called the A11 processor "a marvelous feat of engineering", writing that it offers "industry-leading performance". Axon also praised the cameras, writing that "The colors are great, and low light performance is very good for a smartphone". Chris Velazco of Engadget praised the speed of the A11 processor, the build quality and the "excellent" camera, while criticizing design familiarities with previous iPhone generations and limited water-protection levels compared to competitors.
John McCann of TechRadar enjoyed the feel of the glass back despite criticizing the phone's overall design. McCann also praised the camera and called inductive charging a "useful" addition to the iPhone lineup.
David Pierce of Wired similarly stated that the iPhone 8 models were overshadowed by the iPhone X, despite calling them "virtually perfect phones". Pierce praised performance, cameras, and displays, while repeatedly criticizing the "outdated" design.
Nilay Patel of The Verge called the iPhone 8 the "default option", noting that the 8 models stand as almost universally overlooked by Apple's other new iPhone launched, the iPhone X. He nevertheless praised the device's form factor for being easy and non-slippery to hold and the display's addition of True Tone technology and upgraded speakers, though he cited issues with inductive charging speed through wireless pads as well as the price of the iPhone 8 Plus 256 GB, which was close to that of the iPhone X. Patel also criticized the iPhone 8's aging design, dating back to the iPhone 6 released in 2014; the most notable critique was of the thick bezels when compared to other 2017 smartphones, designed with nearly bezel-less faces to incorporate larger screens in a similar form factor.
The iPhone 8 and 8 Plus were also criticized for their durability, as drop tests performed showed that the rear glass is not "the most durable glass ever in a smartphone", as claimed by Apple.
Camera testing company DxOMark gave the camera on the iPhone 8 a rating of 92 and 8 Plus a rating of 94, giving them the title of best smartphone cameras tested by the company. The Samsung Galaxy Note 8 later matched the iPhone 8 Plus with an identical overall score of 94. They were later overtaken by the Google Pixel 2, which scored a 98 rating.
Although being the first mobile phone to record 2160p at 60 frames per second, the iPhone 8, 8 Plus and X have been criticized in a review by GSMArena for its mono (single-channel) audio recording for videos, while stereo audio recording for videos has been available on competing mobile phone models for several years, such as the Samsung Galaxy S3 and Sony Xperia S from 2012.
Issues
On August 31, 2018, Apple announced that a "very small percentage" of iPhone 8 devices released between September 2017 and March 2018 contained a manufacturing defect in the logic board. This fault affected iPhone 8 models sold in Australia, China, Hong Kong, India, Japan, Macau, New Zealand, and the United States. Defective devices may experience unexpected reboots, a frozen or unresponsive screen, or may fail to turn on. Users with an affected device, as determined by their serial number, can have their device replaced for free by Apple. This issue does not affect the iPhone 8 Plus.
See also
Comparison of smartphones
History of iPhone
List of iPhone models
List of best-selling mobile phones
Timeline of iPhone models
Notes
References
External links
– official site
Mobile phones introduced in 2017
Computer-related introductions in 2017
Mobile phones with 4K video recording
Mobile phones with pressure-sensitive touch screen
Discontinued flagship smartphones | IPhone 8 | [
"Technology"
] | 1,958 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
55,040,125 | https://en.wikipedia.org/wiki/Zilch%20%28electromagnetism%29 | In physics, zilch (or zilches) is a set of ten conserved quantities of the source-free electromagnetic field, which were discovered by Daniel M. Lipkin in 1964. The name refers to the fact that the zilches are only conserved in regions free of electric charge, and therefore have limited physical significance. One of the conserved quantities (Lipkin's ) has an intuitive physical interpretation and is also known as optical chirality.
In particular, first, Lipkin observed that if he defined the quantities
Optical chirality
The free Maxwell equations imply that .
The precedent equation implies that the quantity is constant. This time-independent quantity is one of the ten zilches discovered by Lipkin. Nowadays, the quantity is widely known as optical chirality (up to a factor of 1/2).
The quantity is the spatial density of optical chirality, while is the optical chirality flux. Generalizing the aforementioned differential conservation law for , Lipkin found other nine conservation laws, all unrelated to the stress–energy tensor. He collectively named these ten conserved quantities the zilch (nowadays, they are also called the zilches) because of the apparent lack of physical significance.
Properties of zilch tensor
The zilch is often described in terms of the zilch tensor, . The latter can be expressed using the dual electromagnetic tensor as
.
The zilch tensor is symmetric under the exchange of its first two indices, and , while it is also traceless with respect to any two indices, as well as divergence-free with respect to any index.
The conservation law means that the following ten quantities are time-independent:
These are the ten zilches (or just the zilch) discovered by Lipkin. In fact, only nine zilches are independent.
The time-independent quantity is known as the 00-zilch and is equal to the aforementioned optical chirality
().
In general, the time-independent quantity is known as the -zilch (the indices run from 0 to 3) and it is clear that there are ten such quantities (nine independent).
It was later demonstrated that Lipkin's zilch is part of an infinite number of zilch-like conserved quantities, a general property of free fields.
History
One of the zilches has been rediscovered. This is the zilch called "optical chirality", named by Tang and Cohen, since this zilch determines the degree of chiral asymmetry in the rate of excitation of a small chiral molecule by an incident electromagnetic field.
A further physical insight of optical chirality was offered in 2012; optical chirality is to the curl or time derivative of the electromagnetic field, what helicity, spin and related quantities are to the electromagnetic field itself.
The physical interpretation of all zilches for topologically non-trivial electromagnetic fields was investigated in 2018.
Since the discovery of the ten zilches in 1964, there is an important open mathematical question concerning their relation with symmetries. (Recently, the full answer to this question seems to have been found ). This is the question:
What are the symmetries of the standard Maxwell action functional:
(with and is the dynamical field variable) that give rise to the conservation of all zilches using Noether's theorem. Until recently, the answer to this question had been given only for the case of optical chirality by Philbin in 2013.
This open question was also emphasized by Aghapour, Andersson and Rosquist in 2020,
while these authors found the symmetries of the duality-symmetric Maxwell action underlying the conservation of all zilches. (Aghapour, Andersson and Rosquist did not find the symmetries of the standard Maxwell action, but they speculated that such symmetries should exist ).
There are also earlier works studying the conservation of zilch in the context of duality-symmetric electromagnetism, but the variational character of the corresponding symmetries was not established.
The full answer to the aforementioned question seems to have been given for the first time in 2022, where the symmetries of the standard Maxwell action underlying the conservation of all zilches were found. According to this work, there is a hidden invariance algebra of free Maxwell equations in potential form that is related to the conservation of all zilches.
See also
Conservation law
Noether's theorem
References
Electromagnetism
Conservation laws
Chirality | Zilch (electromagnetism) | [
"Physics",
"Chemistry",
"Biology"
] | 934 | [
"Pharmacology",
"Physical phenomena",
"Electromagnetism",
"Origin of life",
"Equations of physics",
"Biochemistry",
"Conservation laws",
"Stereochemistry",
"Chirality",
"Fundamental interactions",
"Asymmetry",
"Biological hypotheses",
"Symmetry",
"Physics theorems"
] |
55,043,244 | https://en.wikipedia.org/wiki/2%2C2%27-Bipyrimidine | 2,2′-Bipyrimidine is an organic compound with the formula (C4H3N2)2. It is a derivative of the heterocycle pyrimidine. It is a white solid. The compound is used as a bridging ligand in coordination chemistry.
2,2′-Bipyrimidines can be prepared by Ullmann coupling of 2-iodopyrimidines.
References
Chelating agents
Pyrimidines | 2,2'-Bipyrimidine | [
"Chemistry"
] | 100 | [
"Chelating agents",
"Process chemicals"
] |
55,045,858 | https://en.wikipedia.org/wiki/Carl%20L.%20Alsberg | Carl L. Alsberg (April 2, 1877 – October 31, 1940) was an American chemist who served as Commissioner of Food and Drugs from 1912 to 1921.
Alsberg was born to a secular German-Jewish family, the oldest of four children. His father Meinhard, a chemist who immigrated to the U.S. from Germany in 1865, was a founder of the American Chemical Society. Carl Alsberg attended Columbia University, where he founded a literary magazine, The Morningside. He graduated from Columbia College in 1896. He spent three years (1900–1903) studying in Germany before taking up a position as an instructor in biological chemistry at Harvard University.
After teaching at Harvard, Alsberg went to work for the U.S. government in 1908, and from 1912 to 1920 served as Chief of the United States Bureau of Chemistry, which would be renamed the Food and Drug Administration. In that role, Alsberg pursued an investigation into pepper adulteration at McCormick & Company which resulted in a fine and a court order that the company must label its product as "ground black pepper containing from 10 percent to 28 percent added pepper shells". Alsberg also investigated Monsanto's use of saccharin and the amount of caffeine in Coca-Cola.
In 1921, Alsberg resigned from the Bureau of Chemistry and co-founded Stanford University's Food Research Institute.
In 1937, he took a position at the University of California, Berkeley. In 1940, after visiting family in New York, Alsberg became ill with pneumonia on the train trip back to California and died in the hospital on October 31.
References
External links
1877 births
1940 deaths
Columbia College (New York) alumni
American food chemists
Commissioners of the Food and Drug Administration
Taft administration personnel
Woodrow Wilson administration personnel
Harding administration personnel
University of California, Berkeley faculty | Carl L. Alsberg | [
"Chemistry"
] | 367 | [
"Food chemists",
"American food chemists"
] |
55,045,960 | https://en.wikipedia.org/wiki/Yoda1 | Yoda1 is a chemical compound which is the first agonist developed for the mechanosensitive ion channel PIEZO1. This protein is involved in regulation of blood pressure and red blood cell volume, and Yoda1 is used in scientific research in these areas.
See also
Jedi1 and Jedi2
References
Thioethers
Pyrazines
Thiadiazoles
Chloroarenes | Yoda1 | [
"Chemistry"
] | 83 | [
"Pharmacology",
"Pharmacology stubs",
"Medicinal chemistry stubs"
] |
55,046,901 | https://en.wikipedia.org/wiki/LG%20UX | LG UX is an Android-based mobile operating system developed and maintained by LG Electronics independently of Google exclusively for its smartphones.
There are different versions for each LG phone, and each version has variants according to the regions in which the phone is sold, such as China, Japan, Pakistan, Russia, Indonesia, India, Taiwan and Turkey.
The original name of LG UX is Optimus UI, and was given the current name with the launch of the LG G4 and the release of LG UX 4.0, with older versions retroactively renamed LG UX.
Version history
Devices running LG UX
High-end Phones
LG Wing
G Series
LG G4
LG G4 Beat
LG G4 Stylus
LG G Vista 2
LG G5
LG G5 SE
LG G6
LG G6+
LG G7 ThinQ
LG G8 ThinQ
LG G8S ThinQ
LG G8X ThinQ
LG Velvet
LG Velvet 2 Pro
V Series
LG V10
LG V20
LG V30
LG V30+
LG V30 Signature Edition
LG V35 ThinQ
LG V40 ThinQ
LG V50 ThinQ
LG V50S ThinQ 5G
LG V60 ThinQ
Mid to Low-end Phones
K Series
LG K3 (2017)
LG K4 (2017)
LG K8 (2017)
LG K10 (2017)
LG K20 Plus
LG K3
LG K4
LG K5
LG K7
LG K8
LG K10
LG K22
LG K31
LG K41s
LG K41
LG K42
LG K51
LG K52
LG K61
LG K62
Q Series
LG Q6
LG Q7
LG Q8 2017
LG Q8 2018
LG Q Stylus
LG Q Stylo 4
LG Q9
LG Q60
LG Q70
LG Q31
LG Q51
LG Q61
LG Q52
LG Q92 5G
X Series
LG X Screen
LG X Cam
LG X Charge
LG X Style
LG X Power
LG X Power 2
LG X Mach
LG X Max
LG X5
LG X Skin
LG X Venture
Stylus (Stylo) Series
LG G Stylo
LG Stylus 2
LG Stylus 2 Plus
LG Stylus 3
LG Stylus 3 Plus
LG Stylus 4
LG Q Stylo
LG Stylo 5
LG Stylo 6
Other Series
LG Magna
LG Bello 2
LG Zero
LG Ray
Tablets
LG G Pad X
LG G Pad III 8.0
LG G Pad III 10.1
LG G Pad IV 8.0
LG G Pad 5 10.1
References
LG Electronics
Android (operating system) software
Custom Android firmware | LG UX | [
"Technology"
] | 619 | [
"Mobile computer stubs",
"Mobile technology stubs"
] |
55,047,116 | https://en.wikipedia.org/wiki/Strudiella | Strudiella devonica is a species of extinct arthropod from the Devonian. It was recovered in the Strud (Gesves, Belgium) environment from the Bois des Mouches Formation, Upper Famennian. It was originally described as the first complete Late Devonian terrestrial insect, but due to its poor state of preservation, its affinity is discussed.
Description
Strudiella is known from a single specimen. It is a small arthropod with length about . Structures like antennae and a number of pairs of legs can be seen. Due to the poorly preserved nature of this fossil, its interpretation and classification depend on the authors.
Garrouste et al. (2012)
In the first description by Garrouste et al. (2012), it was described as the first complete Devonian insect. The median abdominal structures are filled with guts, which excludes the possibility that is a molting shell. It is interpreted to have 3 pairs of legs from the thorax, the tibiae and femora are long and thin. The antennae are uniramous, the scape and pedicel are wider than the 10-segmented flagellum. The triangular mandibles have a continuous series of sharp, small irregular molar and incisor cusps. Its small head had large eyes. The large thorax had a rounded structure covering its head, corresponding to an expanded pronotum. The abdomen had 10 segments (while a drawing in the paper shows 11 segments), and the authors considered that it lacked any lateral leglets, gills or other appendicular structures. There is a rounded apical structure on the tip of the abdomen. The lack of wings and small size would indicate that it is a nymph. It is interpreted to be a terrestrial insect, and the mandible morphology suggests its diet would be fungivore and/or saprophagy.
Hörnschemeyer et al. (2013)
However, Hörnschemeyer et al. (2013) questioned its interpretation as an insect. The mandible and its teeth cannot be confirmed, the mandibular teeth would be caused by the idiosyncratic way the rock parted. The eyes are vague, the indication of eye rims by Garrouste et al. is considered as arbitrary. The scape, pedicel and flagellum on its antennae cannot be confirmed, and the whole antennae is wider than the legs which is highly unusual for insects. The alleged subdivision of the trunk into thorax and abdomen is also questionable. Importantly, over 3 pairs of legs can be observed. This poor state of preservation allows numbers of alternate interpretations like a decayed crustacean.
Garrouste et al. (2013)
In the same volume of Nature, Garrouste et al. replied to Hörnschemeyer et al. (2013). They supported mandibular teeth structure again. They argued that visible maxillary palps are abnormal under the crustacean hypothesis. They considered that scape, pedicel and flagellum can be confirmed from width of antennae, and antennae being wider than legs would not deny insect affinity. For the extra legs that Hörnschemeyer et al. confirmed, they considered as internal organs extruded during compression and decay.
Other studies
Multiple later studies about Strud fossils call Strudiella as "putative insect". Haug and Haug (2017) listed presumed Devonian insect fossils, and commented that "Its very incomplete preservation makes its interpretation problematic".
Importance of discovery
The discovery of Strudiella as a Devonian insect reduces a previous gap of 45 million years in the evolutionary history of insects, part of the arthropod gap (the 'gap' still occurs in the early Carboniferous, coinciding and extending past the Romer's gap for tetrapods, which may have been caused by low oxygen levels in the atmosphere). However, Hörnschemeyer et al. (2013) which denied its interpretation as insect commented that it is crucial to prevent this fossil from entering entomology textbooks. Most of fossil records of Devonian insects like Rhyniognatha or Leverhulmia are questionable, and the early fossil records of insects still remains scarce and problematic.
See also
Evolution of insects
References
External links
Fossil taxa described in 2012
Late Devonian animals
Famennian life
Fossils of Belgium
Evolution of insects
Taxa named by Michael S. Engel
Controversial taxa
Devonian arthropods of Europe | Strudiella | [
"Biology"
] | 920 | [
"Biological hypotheses",
"Controversial taxa"
] |
55,048,075 | https://en.wikipedia.org/wiki/Nature%20Ecology%20and%20Evolution | Nature Ecology and Evolution is an online-only monthly peer-reviewed scientific journal published by Nature Portfolio covering all aspects of research on ecology and evolutionary biology. It was established in 2017. Its first and current editor-in-chief is Patrick Goymer.
According to the Journal Citation Reports, Nature Ecology and Evolution has a 2020 impact factor of 15.46.
References
External links
Nature Research academic journals
Academic journals established in 2017
Ecology journals
Monthly journals
English-language journals | Nature Ecology and Evolution | [
"Environmental_science"
] | 94 | [
"Environmental science journals",
"Ecology journals",
"Environmental science journal stubs"
] |
55,048,573 | https://en.wikipedia.org/wiki/Ionotropic%20GABA%20receptor | Ionotropic GABA receptors (iGABARs) are ligand-gated ion channel of the GABA receptors class which are activated by gamma-aminobutyric acid (GABA), and include:
GABAA receptors
GABAA-ρ receptors
The GABAB receptor, a G protein-coupled receptor, is the only metabotropic GABA receptor and its mechanism of action differs significantly from the ionotropic receptors. Functionally, in mature organisms, activation of these receptors typically results in neural inhibition, primarily via the influx of chloride ions, although exceptions to this general principle exist, such as during early development. Structurally, iGABARs are pentameric transmembrane ion channels, meaning they are made up of five subunits. Since there are several classes of subunits and a variety of genes encoding many members of these classes, a wide variety of structurally, and therefore functionally, distinct channels of iGABARs is observed.
Introduction
The neuromuscular junction in the CNS can be composed of a presynaptic unit located at an axon terminal with synaptic vesicles and a postsynaptic unit located at a dendrite. Neurotransmitters are chemical molecules that are released from a presynaptic unit into the synapse and received by the postsynaptic unit, resulting in a biological and electrophysiological effect. The two main types of neurotransmitters are amino acid transmitters and GABA transmitters. The release of and binding of glutamate, an amino acid transmitter, to its respective receptor manifests in an excitatory postsynaptic potential. On the other hand, the release and binding of gamma-amino butyric acid (GABA) to the GABA receptor results in an inhibitory postsynaptic potential. The ability of the GABA receptor function rests on its molecular structure of multiple binding sites and conductance levels. These receptors are prevalent in interneurons relaying messages among various regions of the brain.
The difference between ionotropic and metabotropic GABA receptors
The two types of GABA receptors are the GABAA and GABAB receptors. The pentameric GABAA receptors are ionotropic, meaning that upon binding with the ligand their biological and electrophysiological effect is carried out through the conductance of ions. This is why the physiological makeup for GABAA receptors differs from GABAB in that they are ligand-gated ion channels. The chloride-ion gated channels facilitate the inhibitory effect through the influx of chloride ions. However, GABAB receptors are metabotropic meaning they utilize a G-protein coupled mechanism. Since the G-protein is a heterodimeric molecule, the separation and phosphorylation of its parts result in a signal cascade, resulting in a more steady but amplified response.
Pharmacological implications
Earlier a third type of GABA receptor was discovered and named GABAC, but recently it has been categorized as a sub-type of the GABAA receptor. Thus, the iontropic GABA receptors consist of the GABAA receptor and the GABAA-ρ receptor. There are pharmacological implications in understanding the molecular structure and function of these ionotropic receptors. Since they are targeted by neuroactive drugs, this characteristic is exploited in order to deduce their molecular structure and function in the CNS. For example, GABAA receptors respond to neuroactive drugs like benzodiazepines. Normally increasing a neuron's permeability to chloride ions results in inhibition; bensodiazepines further propagate this event ensuring inhibition, serving as an indirect factor. Armed with the knowledge of chloride ion permeability leading to inhibition, it is important to note that ethanol and barbiturates can directly increase the influx of chloride ions resulting in inhibition. Further characterization of the allosteric modulations of the active sites in the ionotropic gives insight on new treatments and nervous system disorders, such as panic disorder.
References
GABA
Ionotropic receptors | Ionotropic GABA receptor | [
"Chemistry"
] | 854 | [
"Ionotropic receptors",
"Signal transduction"
] |
55,048,936 | https://en.wikipedia.org/wiki/N-Nitrosamides | Nitrosamides are chemical compounds that contain of the chemical structure R1C(=X)N(–R2)–N=O, that is, a nitroso group bonded to the nitrogen of an amide or similar functional group. Specific classes include the N-nitrosamides, N-nitrosoureas, N-nitrosoguanidines, and N-nitrosocarbamates. Nitrosamides are usually chemically reactive, metabolically unstable, and often carcinogenic; however, in contrast to the N-nitrosamines, N-nitrosamides are not generally contaminants found in food.
Use
Various chloroethylnitrosoureas (such as [[Carmustine|N, N-bis (2-chloroethyl)nitrosourea]], BCNU) have obtained a medical use in the field of malignant tumors. It is hypothesized that the efficacy against cancer cells is based on the alkylability of guanine cytosine centers in the sequences of the genetic material, especially the oncogenes.
Synthesis
N-Nitrosamides can be prepared starting from N-monosubstituted carboxamides and the nitrosyl cation (which results from the nitrous cation in the presence of strong acids from the nitrous acid), here exemplified for N-methylacetamide (1).Heinz G. O. Becker, Rainer Beckert, Werner Berger, Günter Domschke, Egon Fanghänel, Mechthild Fischer, Frithjof Gentz, Karl Gewald, Reiner Gluch, Wolf D. Habicher, Hans-Joachim Knölker, Roland Mayer, Peter Meth, Klaus Müller, Dietrich Pavel, Hermann Schmidt, Karl Schollberg, Klaus Schwetlick, Erika Seiler, Günter Zeppenfeld: Organikum. 24. Auflage, Wiley-VCH Verlag GmbH & Co.KGaA, Weinheim 2015, , S. 648. The carboxamide reacts in a nucleophilic attack at the nitrosyl cation. After the elimination of a proton, an N-nitrosamide (2) is formed from the resulting cation:
Toxicity
The genotoxic effect of the N-nitroso compounds can be attributed to the formation of reactive electrophilic species in the metabolism. The spontaneous decomposition of N-nitroso-ureas in the aqueous medium of the metabolism, here for example of 1-methylnitrosourea (3), produces diazonium or carbenium ions, respectively. The decomposition occurs into isocyanic acid and methyldiazohydroxide. The rearrangement to the diazonium ion and the subsequent elimination of nitrogen results in a carbenium ion (4'''), which can alkylate nucleophilic intersections of the DNA.
In the organism, the decomposition of N-nitroso ureas with a higher degree of substitution can proceed. An alternative possible formation of diazonium and carbenium ions is through the enzymatic reaction of nitrosamines.
Typical accompanying symptoms during the medical cancer treatment via N''-nitroso ureas are the impairment of bone marrow (damage of the stem cell compartment), lymphatic tissue and the gastrointestinal tract.
References
External links
Nitroso compounds
Amides | N-Nitrosamides | [
"Chemistry"
] | 744 | [
"Amides",
"Functional groups"
] |
55,050,540 | https://en.wikipedia.org/wiki/Baron%20%26%20Budd%2C%20P.C. | Baron & Budd, P.C. is an American plaintiffs' law firm headquartered in Dallas, Texas. Opponents of mass tort litigation have criticized the firm for the zealousness with which it represents its clients, and for the political activities of some of its attorneys.
History
Establishment and early practice
Baron & Budd began its practice in 1977. The firm's first major case involved a lead smelter adjacent to one of the largest public housing projects in Dallas. Baron & Budd represented more than 200 families in a lawsuit that eventually closed the smelter and provided sizable damage awards for court-supervised trusts that benefited several hundred children. For most of its existence, Baron & Budd has maintained a substantial presence in "litigation against former asbestos manufacturers and companies that used asbestos products", being one of the first law firms in the U.S. to successfully try mesothelioma cases. The firm's clients in this practice have included celebrities such as actor Paul Gleason, who died from mesothelioma in 2006.
The firm has also practiced widely in other areas of mass torts, including such matters as "Benzene exposure, Fen-Phen diet drug litigation and water contamination". In 1985, Baron & Budd filed suit on behalf of more than 1,600 Tucson-area residents against an aircraft manufacturer, the City of Tucson, and the Tucson Airport Authority over trichloroethylene (TCE) contamination of the community's groundwater. Throughout the ensuing 21-year legal battle, in which Baron & Budd ultimately prevailed, the law firm helped to define Arizona law on pollution coverage. In 2006, Baron & Budd attorneys were honored with the Trial Lawyer of the Year award by Trial Lawyers for Public Justice, "in recognition of their firms work in precedent-setting litigation involving groundwater contamination in Arizona".
Another key development for the firm occurred in 1997, when the United States Supreme Court decided Amchem Products, Inc. v. Windsor. In that case, plaintiffs represented by various attorneys, including those from Baron & Budd, objected to the fairness of a class action settlement approved by the district court on behalf of injured parties not effectively represented before the court. The record for a successful appeal was developed "[t]hanks largely to lawyers at Baron & Budd, a firm representing some of the objectors" which insured that "there were more than 30 depositions, other discovery, and an 18-day fairness hearing". This outcome was reinforced within the next few years in a case also brought to fruition by Baron & Budd, Ortiz v. Fibreboard Corp.<ref>Ortiz v. Fibreboard Corp., 527 US. 815 (1999).</ref> The decisions in these cases "compel appellate courts to look skeptically at class action settlements that release defendants from claims by absent plaintiffs". During this period, the firm received both criticism and praise for the zealousness with which it represented its clients.
Developments in the 2000s and 2010s
In 2003, Baron & Budd represented the City of Santa Monica in a landmark MTBE contamination settlement with the major oil companies. MTBE contaminated five of Santa Monica's 11 wells, forcing the city to begin importing water in 1996 for $3 million a year. In 2006, firm founder Russell Budd "helped secure a $3.9 billion settlement with the United States Gypsum Co. on behalf of the asbestos creditors committee in one of the largest bankruptcy settlements on record". Other notable cases by Baron & Budd in this time included "a 13.5 million-dollar verdict on behalf of the family of an East Texas man who died of mesothelioma as a result of asbestos exposure in his childhood, and a 15.5 million dollar jury verdict in a Mississippi lawsuit involving dioxide emissions". In 2008, Baron & Budd played a lead role in negotiations with major oil companies that had contaminated drinking water through the use of MTBE as a gasoline additive. Baron & Budd's efforts resulted in a landmark settlement, requiring the oil companies to pay a substantial cash settlement, nearly $1.5 billion, to 153 public water providers in 17 states, as well as a number of private well owners.
In August 2010, environmental attorney and Baron & Budd shareholder Burton LeBlanc of Baton Rouge, Louisiana, and Baron & Budd were retained by the state of Louisiana to provide counsel to the state's designated trustees in connection with issues related to the Deepwater Horizon explosion and the resulting oil spill. In October 2010, Scott Summy, the head of Baron & Budd's water contamination team, was one of four attorneys nationwide chosen to serve on the Plaintiffs' Executive Committee for the Gulf Oil Spill Multi-District Litigation (MDL) and as a member of the Plaintiffs' Steering Committee (PSC). In 2011, Baron & Budd, along with co-counsel, represented the first Chinese drywall client to be remediated by the Chinese Sheetrock manufacturer Knauf.
Several of the firm's attorneys developed political connections over time. Partner Russell Budd and his wife, Dorothy, hosted President Barack Obama at their home in August 2010. Partner Fred Baron served as co-chair of the Kerry Victory '04 committee, a joint effort of the Democratic National Committee and the Presidential campaign of John Kerry. The New York Times listed Baron & Budd as the sixth biggest source of contributions to state attorneys general campaigns from 2004 to 2014.
In September 2014, the National Law Journal identified Baron & Budd as "Elite Trial Lawyers", noting that "Baron & Budd is best known for its asbestos work but its interests run much broader than that". Baron & Budd was named to "The Plaintiffs' Hot List" of the National Law Journal'' from 2003 to 2006, in 2008, and again in 2011 and 2012, and attorneys from the firm have repeatedly been named to the "Best Lawyers in America" list, receiving this honor for four years in a row, from 2013 to 2017.
Recent developments
In September 2017, Baron & Budd was one of two firms hired to represent Brunswick County, North Carolina in the investigation of chemical contamination of drinking water drawn from the Cape Fear River, alleged to involve the manufacture of perfluorinated chemicals (PFCs) by Chemours, DuPont and Kuraray at a facility in Fayetteville, North Carolina.
Baron & Budd has twice represented plaintiffs against Wells Fargo regarding practices by that company. In November 2016, Baron & Budd represented homeowners whose home appraisal fees had allegedly been marked up by the bank, and negotiated a $50 million settlement after winning certification of the claim as a class action. In July 2017, the firm filed a lawsuit alleging that the bank had charged auto loan customers for unnecessary insurance, causing some customers to have their cars repossessed.
The firm is representing the cities of Louisville, Cincinnati, and Birmingham, among other counties and municipalities, in litigation against opioid distributors, in response to the crisis of opioid addiction. Their Environmental Litigation Group is representing public entities, including the cities of Spokane and Seattle, as well as the State of Washington, in litigation against Monsanto-related PCB contamination.
In 2017 Baron & Budd investigated potential lawsuits that were related to allegations that pharmaceutical distributors "deliberately failed to monitor and report suspicious orders of opioids". This failed monitoring and reporting, the firm argued, potentially played a role in the opioid epidemic. The law firm had previously won a $177 million settlement against GlaxoSmithKline for the drug Avandia, arguing that the company misrepresented the drug by saying that it reduced the number of adverse cardiac events, when in actuality it did not.
References
External links
Law firms based in Dallas
Asbestos | Baron & Budd, P.C. | [
"Environmental_science"
] | 1,603 | [
"Toxicology",
"Asbestos"
] |
55,050,738 | https://en.wikipedia.org/wiki/Keynes%E2%80%93Ramsey%20rule | In macroeconomics, the Keynes–Ramsey rule is a necessary condition for the optimality of intertemporal consumption choice. Usually it is expressed as a differential equation relating the rate of change of consumption with interest rates, time preference, and (intertemporal) elasticity of substitution. If derived from a basic Ramsey–Cass–Koopmans model, the Keynes–Ramsey rule may look like
where is consumption and its change over time (in Newton notation), is the discount rate, is the real interest rate, and is the (intertemporal) elasticity of substitution.
The Keynes–Ramsey rule is named after Frank P. Ramsey, who derived it in 1928, and his mentor John Maynard Keynes, who provided an economic interpretation.
Mathematically, the Keynes–Ramsey rule is a necessary first-order condition for an optimal control problem, also known as an Euler–Lagrange equation.
See also
Ramsey–Cass–Koopmans model
References
Further reading
Economic growth
Intertemporal economics
Mathematical optimization | Keynes–Ramsey rule | [
"Mathematics"
] | 210 | [
"Mathematical optimization",
"Mathematical analysis"
] |
55,050,801 | https://en.wikipedia.org/wiki/Ruwais%20Refinery | The Ruwais Refinery is operated by the Abu Dhabi National Oil Company (ADNOC). The complex can process up to 837,000 barrels of crude oil and condensate per day, making it the fourth-largest single-site oil refinery in the world and the biggest in the Middle East. The refinery is situated in the city of Ruwais, in Abu Dhabi’s western region. It is highly integrated with ADNOC’s other plants in the Ruwais industrial area – such as the Borouge 3 petrochemical plant.
History
The Ruwais Refinery was inaugurated by the late Sheikh Zayed Bin Sultan Al Nahyan in 1982 as part of his vision to transform the area into a hub for oil and gas processing. Over subsequent decades, the site has grown in capacity and complexity to include a Hydrocracker Plant (1985), a Condensate Plant (2000), a Gasoline Plant (2006), a Green Diesel Plant (2011), and a Base Oil Plant (2016). Today, the complex is known locally as Ruwais Refinery East. It has a processing capacity of 420,000 bpd consisting of 140,000 bpd of crude oil and 280,000 bpd of condensates.
In 2014, a second complex was opened to meet the growing demand for ADNOC’s refined products. Known locally as Ruwais Refinery West, the facility can process up to 417,000 crude oil barrels per day. It contains the world’s largest residue catalytic cracking (RFCC) unit, allowing for 127,000 barrels of heavy residue to be upgraded into middle distillates every day. In 2018, the refinery opened a carbon black and delayed coker plant, producing up to 430,000 tons per year of anode-grade calcined coke and 40,600 tons per year of carbon black. Other products include liquefied petroleum gas (LPG), unleaded gasoline, diesel, naphtha, jet-A1, base-oil, fuel oil, white spirit, and propylene.
The Ruwais Refinery is connected to three jetties equipped with multiple berths to allow for cargo transfers via the Arabian Sea. It is also connected to a pipeline network spanning over 1,600 km across the emirate, allowing for essential fuels to be distributed to sites like the Abu Dhabi International Airport.
The refinery also runs a General Utilities Plant, which supplies power and water to the entire Ruwais industrial area and two environmental protection facilities to treat and dispose of industrial waste safely.
In 2019, the European energy firms Eni and OMV entered into a partnership deal with ADNOC Refining. These companies respectively hold 20% and 15% of the Ruwais Refinery under the joint venture, with ADNOC owning the remaining 65%.
Upcoming Projects
Work is underway to diversify the range of crude oil being refined in Ruwais. Once complete in 2022, the $3.5bn Crude Flexibility Project will give ADNOC Refining the ability to process 420,000 bpd of grades such as Upper Zakum – and over 50 others – to increase value.
References
Oil refineries in the United Arab Emirates | Ruwais Refinery | [
"Chemistry"
] | 656 | [
"Petroleum",
"Petroleum stubs"
] |
55,051,090 | https://en.wikipedia.org/wiki/Homophobia%20%28film%29 | Homophobia is a 2012 Austrian short film directed by Gregor Schmidinger and produced by Schmidinger and Julian Wiehl. The film had its premiere in Vienna on 11 May 2012, and was released online on 14 May 2012 as a contribution to the International Day Against Homophobia, Transphobia and Biphobia on 17 May 2012. The film stars Michael Glantschnig, Josef Mohamed, Günther Sturmlechner and Harald Bodingbauer. Homophobia is set in the 1990s during the winter solstice, and is about a young Austrian soldier, Michael (played by Glantschnig), who attempts suicide using a firearm, because of bullying over his homosexuality, during a watch on the Austrian-Hungarian border on the last night of his seven-week military service.
Plot
According to Vangardist, the film is set in the 1990s during the winter solstice and shows the "contrasts [of] the hyper-masculine world of military service". It begins with a scene at night, showing Raphael (played by Josef Mohamed) pushing a gun into Michael's mouth (played by Michael Glantschnig); both are wearing military uniforms. The film then introduces to Michael, a young, gay Austrian soldier, in a military camp, who wakes up, vomits into a toilet, and starts crying. Entering the bathroom for a shower, Jürgen (played by Günther Sturmlechner) holds him from behind while Raphael turns cold water on him. After throwing Jürgen to the floor, Michael disappears to the cloakroom. Jürgen approaches him again and claims to know "all about [his] little secret," his homosexuality, while he touches Michael's body, and then throws him against a wall. When asked later by the commanding officer (played by Harald Bodingbauer) about the resulting wound on his eyebrow, Michael lies, telling him he slipped in the bathroom. Preparing for a watch on the Austrian-Hungarian border on the last night of a seven-week military service, Michael hears Jürgen joking about homosexuality with two fellow platoon mates.
Michael finally arrives with his duty partner Raphael at a tent in a forest for their eight-hour watch. Later when they sit together on what appears to be a bank, Raphael starts talking about his girlfriend, but seems unsure about his sexual orientation. He also apologises for his bad behaviour towards Michael and offers him a cigarette. After smoking cannabis with Raphael, Michael, who experiences a rush from the drug, attempts to kiss him. Raphael fends him off aggressively. After this, Michael takes his gun and walks away, first pointing it at Raphael, and then wanting to commit suicide by shooting himself because of the bullying by his fellow soldiers. A desperate Raphael demands that Michael put the gun down, and finally manages to get the weapon out of his hands. Michael then falls to the ground and starts to cry. The film ends with Raphael hugging him.
Background and production
Prior to the release of Homophobia, Schmidinger released the gay-themed short film The Boy Next Door in 2008. One of his inspirations for Homophobia was the suicide of Jamey Rodemeyer in 2011, attributed to bullying due to his homosexuality, and a video Rodemeyer had submitted for the Internet-based 501(c)3 non-profit It Gets Better Project. A casting call for the film was issued online, with actors sending "motivational" videos stating why they wished to join the cast. Although the title of the film was deemed generic by the audience, Schmidinger defended it as it "provides a way of reaching a broader audience with a single word: search engine optimization meets art".
For filming, a Canon EOS C300 was chosen for its ability to film low light scenes, and the camera's sharpness. Electric generator trucks were used for some low light sequences. With the local mayor's support, the film was shot at a former tobacco factory in Linz that had been repurposed to host film and other art productions, and the woods surrounding it. Several scenes have the actors' faces very near to the camera. For the filming of a bathroom scene, several male actors had to be nude. Money for the film's production was raised through crowdfunding on the Indiegogo website, where $10,100 was donated in 69 days. People who donated were invited to be a "dynamic" part of the project and to visit a Facebook forum, where they could review the ongoing production and make suggestions. The project was also supported financially by the Queeren Kleinprojektetopf organization in Vienna. The box office earnings were donated to the It Gets Better project.
Homophobia was originally intended to have a happy ending, but it was removed by Schmidinger. In an interview, he confessed, "a cheesy ending was out of the question for me. ... The happy endings of feature movies never really happen in real life. Still, I think and hope that the audience will be left with a positive feeling at the end of the film." During a behind-the-scenes video, it was revealed that the final scene was to have featured Michael and Raphael meeting as friends at a train station after their military service.
Release
Homophobia'''s premiere was a special event at the Gartenbaukino in Vienna on 11 May 2012 at around 21:00. The audience included the film's supporters and invited guests from politics, media and business. A meat market, "Homophobia Is Not Invited", was also launched supporting the release of the film. Homophobia was uploaded onto Schmidinger's YouTube channel on 14 May 2012 as a contribution to the International Day Against Homophobia, Transphobia and Biphobia on 17 May 2012. It was also intended to be shown in schools to "facilitate a dialogue about homophobia and self-acceptance," and was handed both offline and online to other film festivals. For marketing purposes, Manuel Dünfründt was hired as a publicist.
Response to the "abrupt" and "gloomy" ending was primarily negative.
Controversy
In February 2017, the bathroom scene sparked controversy for possibly featuring a 25-year-old man in the background, known as Harald Z. Under the alias of Harald Hitler, he had been arrested that month for glorifying Adolf Hitler, by impersonating him in Braunau am Inn, a punishable offense in Austria. When interviewed by Vice'' magazine, Schmidinger responded, "We think he is it. We do not really know him and had no contact with him after the [film's] premiere in 2012. At that time, we searched online for extras and he showed up. We are just a bit perplexed." Harald Z. is credited as part of the film's cast.
References
External links
2012 films
LGBTQ-related short films
2010s German-language films
Austrian short films
Films set in the 1990s
2012 independent films
Crowdfunded films
Gay-related films
2012 short films
2012 LGBTQ-related films
Winter solstice
Films about anti-LGBTQ sentiment
Austrian LGBTQ-related films | Homophobia (film) | [
"Astronomy"
] | 1,458 | [
"Astronomical events",
"Winter solstice"
] |
55,051,898 | https://en.wikipedia.org/wiki/Math%20Prize%20for%20Girls | The Advantage Testing Foundation Math Prize for Girls, often referred to as The Math Prize for Girls, is an annual mathematics competition open to female high school students from the United States and Canada. The competition offers the world’s largest single monetary math prize in a math contest for young women. In 2017, the First-Place prize was $46,000 (split equally amongst the three-way tie for first) with another $9,000 divided among the remaining finalists. Girls may win a maximum of $100,000 by participating in the competition over multiple years. Organized each year by the Advantage Testing Foundation, the competition is considered to be the preeminent female math competition for young women in North America.
The single-day annual contest is open to female high-school students in 12th grade or below, from the United States and Canada who have attained a qualifying score on the American Mathematics Competitions Exams, specifically the AMC 10 or AMC 12 given in February each year. Up to 300 participants are then selected each year for the competition. Participants must complete 20 short-answer problems in geometry, algebra, trigonometry, and other math topics in 150 minutes. The exams are then reviewed by a panel of judges, who award cash prizes to the top-scoring participants.
History
The competition was founded in 2009 by Arun Alagappan and Dr. Ravi Boppana in an effort to inspire the next generation of female mathematicians and create a community of young women who share a passion for math. Boppana, the competition’s cofounder and Director, said in a statement that "the Math Prize was created to debunk gender stereotypes, and to support young women who see higher-level mathematics as a pursuit that is challenging, fun, and incredibly rewarding.” The first two years of the competition were held at NYU, and since 2011, the competition has been held annually at MIT in Cambridge, Massachusetts.
Winners
The annual first-place winners of The Math Prize for Girls are listed in the table below:
The competition was not held in 2020 or 2021 due to the COVID-19 pandemic.
Additionally, the Math Prize for Girls awards Youth Prize to the highest scoring student in grade 9 or below.
Advisory board
As of 2017, the competition's Board of Advisors has the following members:
Ravi Boppana, Director of Mathematics at Advantage Testing, Inc.
Ioana Dumitriu, Professor of mathematics at the University of California, San Diego
Maria Klawe, President of Harvey Mudd College
Richard Rusczyk, Founder of Art of Problem Solving, Inc. and Director of the USA Mathematical Talent Search
Michael Sipser, Professor of Applied Mathematics and Dean of Science at MIT
Gigliola Staffilani, the Abby Rockefeller Mauze Professor of Mathematics at MIT
Lauren Williams, Professor of mathematics at the Harvard University
Joseph Woo
Melanie Wood, Professor of mathematics at the University of Wisconsin-Madison
References
External links
Mathematics competitions
Educational foundations in the United States
Recurring events established in 2009
Women in mathematics | Math Prize for Girls | [
"Technology"
] | 608 | [
"Women in science and technology",
"Women in mathematics"
] |
55,052,772 | https://en.wikipedia.org/wiki/NGC%204466 | NGC 4466 is an edge-on spiral galaxy located about 50 million light-years away in the constellation of Virgo. NGC 4466 was discovered by astronomer Bindon Stoney on February 26, 1851. The galaxy is a member of the Virgo Cluster.
See also
List of NGC objects (4001–5000)
References
External links
Spiral galaxies
Virgo (constellation)
4466
41170
7626
Astronomical objects discovered in 1851
Virgo Cluster | NGC 4466 | [
"Astronomy"
] | 91 | [
"Virgo (constellation)",
"Constellations"
] |
55,053,362 | https://en.wikipedia.org/wiki/ESO%20269-57 | ESO 269-57 is a large barred spiral galaxy located about 150 million light-years away in the constellation Centaurus. ESO 269-57 has a diameter of about 200,000 light-years. It is part of group of galaxies known as LGG 342. which is also known as the NGC 5064 Group which is part of the Centaurus Supercluster.
Physical characteristics
ESO 269-57 has an inner ring surrounding its bright center and connected by its bar. The ring is made up of several tightly wound spiral arms. Surrounding the inner ring, are two outer arms made up of star-forming regions that appear to split into several branches of arms.
SN1992K
On March 3, 1992 a type Ia supernova was discovered in ESO 269-57.
See also
List of spiral galaxies
NGC 1291
References
External links
Barred spiral galaxies
Centaurus
45683
269-57
Ring galaxies
Hydra-Centaurus Supercluster | ESO 269-57 | [
"Astronomy"
] | 198 | [
"Centaurus",
"Constellations"
] |
58,214,031 | https://en.wikipedia.org/wiki/Bouvardin | Bouvardin is a bicyclic hexapeptide isolated from Bouvardia ternifolia. Its chemical formula is C40H48N6O10. It is derived from the amino acid sequence Ala-Ala-Tyr-Ala-Tyr-Tyr. It has demonstrated certain anti-cancerous activities by inhibiting protein synthesis through inhibition of 80S ribosomes (eukaryotic ribosomes).
References
Hexapeptides
Cyclic peptides | Bouvardin | [
"Chemistry"
] | 103 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
58,216,096 | https://en.wikipedia.org/wiki/Defluoridation | Defluoridation is the downward adjustment of the level of fluoride in drinking water. Worldwide, fluoride is one of the most abundant anions present in groundwater. Fluoride is more present in groundwater than surface water mainly due to the leaching of minerals. Groundwater accounts for 98 percent of the earth's potable water. An excess of fluoride in drinking water causes dental fluorosis and skeletal fluorosis. The World Health Organization has recommended a guideline value of 1.5 mg/L as the concentration above which dental fluorosis is likely. Fluorosis is endemic in more than 20 developed and developing nations.
History
Fluorosis was not identified as a problem until relatively recently. Few attempts to defluoridate water came before the 20th century. In the 1930s, several nations began to investigate fluoride's negative effects and how best to remove it. An aluminum and sand filter that removes fluorine from water was devised by Dr. S. P. Kramer in 1933; in 1945, M. Kenneth received a French patent for a water defluoridation technique; and in 1952, a functioning activated alumina community defluoridation plant was commissioned in Bartlett, Texas, USA.
Techniques
While various defluoridation techniques have been explored, each has its limitations. Existing techniques are often too costly (because the geographic areas prone to fluorosis are among the poorest regions on the planet), ineffective or even dangerous (some of the remediation processes add other contaminants to the water). The main techniques that have been, and continue to be, investigated with varying degrees of success include: adsorption, precipitation, ion exchange and membrane processes.
Adsorption can be achieved with locally available adsorbent materials with high efficiency and cost-effectiveness. Cost-effective and locally-available herbal and indigenous products offer promising options. The process is dependent on pH and the presence of sulfate, phosphate, and bicarbonate which results in ionic competition. Disposal of fluoride-laden sludge is problematic.
Precipitation is the most well-established and most widely used method, particularly at the community level. However, it has only moderate efficiency and a high chemical dose is required. Excessive use of aluminum salts produces sludge and adverse health effects through aluminum solubility.
The so-called Nalgonda technique for reduction of fluoride involves stirring in of alum and lime, whereupon some of the fluoride precipitates together with aluminum hydroxide, and the water can be decanted and filtered.
Ion Exchange removes fluoride up to 90-95% and retains the taste and colour of the water. Sulphates, phosphates, and bicarbonates also result in ionic competition in this method. Relatively high cost is a disadvantage and treated water sometimes has a low pH value and high levels of chloride.
Membrane processes are effective technique and do not require chemicals. It works at wide pH range and interference by other ions is negligible. Negatives include higher costs and it skilled labour. This process is not suitable for water with high salinity.
Calcium amended-hydroxyapatite is the most recent defluoridation technique in which aqueous calcium is amended to the fluoride contaminated water prior to contact with uncalcined synthetic hydroxyapatite adsorbent. In this novel defluoridation technique, amending aqueous calcium successfully prevents the dissolution of hydroxyapatite during the defluoridation and also enhances the defluoridation capacity of hydroxyapatite. In addition to these features, this ″calcium amended-hydroxyapatite″ defluoridation technique provides calcium-enriched alkaline drinking water and drinking of this defluoridated water may also help in fluorosis reversal. Thus, it is expected that utilization of this defluoridation technique to provide safe drinking water helps in the mitigation of fluorosis.
References
Water treatment | Defluoridation | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 821 | [
"Water treatment",
"Environmental engineering",
"Water technology",
"Water pollution"
] |
58,216,843 | https://en.wikipedia.org/wiki/Spyros%20Magliveras | Spyros Simos Magliveras (born 6 September 1938 in Athens) is a Greek-born American mathematician and computer scientist.
Biography
Magliveras graduated from the University of Florida with a bachelor's degree in electrical engineering in 1961 and a master's degree in mathematics in 1963. He was from 1963 to 1964 an instructor of mathematics at Florida Presbyterian College and from 1964 to 1968 a teaching fellow in mathematics at the University of Michigan, as well as from 1965 to 1968 a programming analyst and a systems analyst at the University of Michigan Institute for Social Research. He received his PhD in mathematics from the University of Birmingham, UK in 1970 with thesis advisor Donald Livingstone and thesis The subgroup structure of the Higman-Sims simple group.
At the State University of New York at Oswego, he was from 1970 to 1973 an assistant professor and from 1973 to 1978 an associate professor. From 1978 to 2000 he was a professor of mathematics and computer science at the University of Nebraska-Lincoln, retiring as professor emeritus in 2000. Since 2000 he has been a professor at Florida Atlantic University (FAU). He was the director of FAU's Center for Cryptology and Information Security from 2003 to 2013, and since 2013 he has been the center's associate director.
He has been a visiting professor at the University of Birmingham (1984/85), at the University of Waterloo (1999), at the Sapienza University of Rome (two months in 2000), and at the University of Western Australia (two months in 2000).
Magliveras does research on combinatorial designs, permutation groups, finite geometries, encryption of data (cryptography), and data security. In 2001 he received the Euler Medal. He is a co-author of the 2007 book Secure group communications over data networks.
Magliveras is married since 1961 and has two children.
References
External links
Homepage at Florida Atlantic University
20th-century American mathematicians
21st-century American mathematicians
American people of Greek descent
Combinatorialists
University of Florida alumni
Alumni of the University of Birmingham
University of Nebraska–Lincoln faculty
Florida Atlantic University faculty
1938 births
Living people
University of Michigan fellows | Spyros Magliveras | [
"Mathematics"
] | 442 | [
"Combinatorialists",
"Combinatorics"
] |
58,217,316 | https://en.wikipedia.org/wiki/James%20William%20Peter%20Hirschfeld | James William Peter Hirschfeld (born 1940) is an Australian mathematician, resident in the United Kingdom, specializing in combinatorial geometry and the geometry of finite fields. He is an emeritus professor and Tutorial Fellow at the University of Sussex.
Hirschfeld received his doctorate in 1966 from the University of Edinburgh with thesis advisor William Leonard Edge and thesis The geometry of cubic surfaces, and Grace's extension of the double-six, over finite fields.
To pursue further studies in finite geometry Hirschfeld went to University of Perugia and University of Rome with support from the Royal Society and Accademia nazionale dei Lincei. He edited Beniamino Segre's 100-page monograph "Introduction to Galois Geometries" (1967).
In 1979 Hirschfeld published the first of a trilogy on Galois geometry, pegged at a level depending only on "the group theory and linear algebra taught in a first degree course, as well as a little projective geometry, and a very little algebraic geometry." When q is a prime power then there is a finite field GF(q) with q elements called a Galois field. A vector space over GF(q) of n + 1 dimensions produces an n-dimensional Galois geometry PG(n,q) with its subspaces: one-dimensional subspaces are the points of the Galois geometry and two-dimensional subspaces are the lines. Non-singular linear transformations of the vector space provide motions of PG(n,q). The first book (1979) covered PG(1,q) and PG(2,q). The second book addressed PG(3,q) and the third PG(n,q). Chapters are numbered sequentially through the trilogy: 14 in the first book, 15 to 21 in the second, and 22 to 27 in the third. Finite geometry has contributed to coding theory, such as algebraic geometry codes, so the field is supported by computer science. In the preface of the 1991 text Hirschfeld summarizes the status of Galois geometry, mentioning maximum distance separable code, mathematics journals publishing finite geometry, and conferences on combinatorics featuring Galois geometry. Colleague Joseph A. Thas is coauthor of General Galois Geometries on PG(n,q) where n ≥ 4.
Hirschfeld was cited as the ultimate editor of Design Theory (1986).
In 2018 he received the 2016 Euler Medal.
Selected publications
1979: Projective Geometries over Finite Fields, Oxford University Press 2nd ed., Oxford, Clarendon Press 1998
1985: Finite Projective Spaces of Three Dimensions, Oxford University Press
1991: (with Joseph A. Thas) General Galois Geometries, Oxford University Press 2016 paperback reprint
2008: (with Gábor Korchmáros & Fernando Torres) Algebraic Curves over a Finite Field, Princeton University Press
References
External links
Prof James Hirschfeld at University of Sussex
Alumni of the University of Edinburgh
Academics of the University of Sussex
20th-century British mathematicians
21st-century British mathematicians
Combinatorialists
Geometers
1940 births
Living people | James William Peter Hirschfeld | [
"Mathematics"
] | 629 | [
"Combinatorialists",
"Geometers",
"Geometry",
"Combinatorics"
] |
58,217,356 | https://en.wikipedia.org/wiki/Industrial%20Mutual%20Association%20Auditorium | The Industrial Mutual Association Auditorium was an auditorium located at 815 East 2nd Avenue in Flint, Michigan.
In 1901, the Flint Vehicle Factories Mutual Benefit Association (FVFMBA) was established by manufacturers in the Flint area. The Association provided benefits to workers in the event of sickness, injury or death, and was funded by contributions from their paychecks. In 1915, the Industrial Fellowship League (IFL) was founded by Charles Stewart Mott, with Walter P. Chrysler as chairman. The League offered workers recreational and educational activities. In 1922, the FVFMBA and the IFL merged to form the Industrial Mutual Association of Flint.
In 1927, the IMA purchased the Randall Lumber and Coal Company property in downtown Flint. There, they constructed an athletic park and an auditorium. The auditorium was constructed in 1929 at a cost of $1.2 million, and financed through mandatory deductions from local autoworkers' pay. The Auditorium served as the venue for many of Flint's athletic, entertainment and social events for the next 50 years. The IMA eventually sold the Auditorium to the Charles Stewart Mott Foundation.
The building was a six-story Romanesque Revival structure that contained halls, offices, gymnasiums, and an auditorium that seated nearly 7000 people.
The last event hosted by the Auditorium occurred in 1979. It was added to the National Register of Historic Places in 1983.
The Auditorium was incorporated into the AutoWorld theme park, which opened in 1984 and limped along until closing permanently in 1994. After two years of staying dormant, the IMA Auditorium was imploded on February 23, 1997. The implosion event was broadcast by WJRT-TV. In November that year, it was removed from the NHRP. The location where it once stood is now a part of the University of Michigan–Flint campus.
References
National Register of Historic Places in Genesee County, Michigan
Romanesque Revival architecture in Michigan
Buildings and structures completed in 1929
1929 establishments in Michigan
Buildings and structures demolished in 1997
1997 disestablishments in Michigan
Buildings and structures demolished by controlled implosion
National Basketball League (United States) venues
Flint Dow A.C.'s
Former National Register of Historic Places in Michigan | Industrial Mutual Association Auditorium | [
"Engineering"
] | 451 | [
"Buildings and structures demolished by controlled implosion",
"Architecture"
] |
58,217,500 | https://en.wikipedia.org/wiki/Polyurethane%20dispersion | Polyurethane dispersion, or PUD, is understood to be a polyurethane polymer resin dispersed in water, rather than a solvent, although some cosolvent may be used. Its manufacture involves the synthesis of polyurethanes having carboxylic acid functionality or nonionic hydrophiles like PEG (polyethylene glycol) incorporated into, or pendant from, the polymer backbone. Two component polyurethane dispersions are also available.
Background
There has been a general trend towards converting existing resin systems to waterborne resins, for ease of use and environmental considerations. Particularly, their development was driven by increased demand for solventless systems since the manufacture of coatings and adhesives entailed the increasing release of solvents into the atmosphere from numerous sources. Using VOC exempt solvents is not a panacea as they have their own weaknesses.
The problem has always been that polyurethanes in water are not stable, reacting to produce a urea and carbon dioxide. Many papers and patents have been published on the subject. For environmental reasons there is even a push to have PUD available both water-based and bio-based or made from renewable raw materials. PUDs are used because of the general desire to formulate coatings, adhesives, sealants and elastomers based on water rather than solvent, and because of the perceived or assumed benefits to the environment.
Synthesis
The techniques and manufacturing processes have changed over the years from those described in the first papers, journal articles and patents that were published. There are a number of techniques available depending on what type of species is required. An ion may be formed which can be an anion thus forming an anionic PUD or a cation may be formed forming a cationic PUD. Also, it is possible to synthesize a non-ionic PUD. This involves using materials that will produce an ethylene oxide backbone, or similar, or a water-soluble chain pendant from the main polymer backbone.
Anionic PUDs are by far the most common available commercially. To produce these, initially a polyurethane prepolymer is manufactured in the usual way but instead of just using isocyanate and polyol, a modifier is included in the polymer backbone chain or pendant from the main backbone. This modifier is/was mainly dimethylol propionic acid (DMPA). This molecule contains two hydroxy groups and a carboxylic acid group. The OH groups react with the isocyanate groups to produce an NCO terminated prepolymer but with a pendant COOH group. This is now dispersed under shear in water with a suitable neutralizing agent such as triethylamine. This reacts with the carboxylic acid forming a salt which is water soluble. Usually, a diamine chain extender is then added to produce a polyurethane dispersed in water with no free NCO groups but with polyurethane and polyurea segments. Dytek A is commonly used as the chain extender. Various papers and patents show that an amine chain extender with more than two functionalities such as a triamine may be used too. Chain extender studies have been carried out.
There is also a push to have a synthesis strategy that is non-isocyanate based. When blocked isocyanates are used there is no isocyanate (NCO) functionality and hence the water reaction producing carbon dioxide so dispersion is easier. Modifiers other than DMPA have been researched.
It is also possible to introduce hydrophilicity into the polymeric molecule by using a modified chain extender rather than doing so in the polymer backbone or a pendant chain. Lower viscosity materials are often the result, as well as higher solids. A variation on this technique is to incorporate sulfonate groups. PUD/polyacrylate blends can be prepared this way also utilizing internal emulsifiers.
Cationic PUD also introduce hydrophilic components when synthesized. This includes phosphonium entities. Techniques have and are being researched to improve the performance and water resistance properties by various techniques. This includes introducing star-branched polydimethylsiloxane.
Research has been done and published that shows it is not the dispersion speed, mechanical agitation or high shear mixing that has the biggest effect on properties, but rather the chemical makeup. However, particle size distribution can be controlled by this to some extent.
Uses
They find use in coatings, adhesives, sealants and elastomers. Specific uses include industrial coatings, UV coating resins, floor coatings, hygiene coatings, wood coatings, adhesives, concrete coatings, automotive coatings, clear coatings and anticorrosive applications. They are also used in the design and manufacture of medical devices such as the polyurethane dressing, a liquid bandage based on polyurethane dispersion. To improve their functionality in flame retardant applications, products are being developed which have this feature built into the polymer molecule. They have also found use in general textile applications such as coating nonwovens. Leather coatings with antibacterial properties have also been synthesized using PUDs and silver nanoparticles. On a similar theme, recent (post 2020) innovations have included producing a waterborne polyurethane that has embedded silver particles to combat COVID. On a similar theme, PUD with antimicrobial properties have been developed.
Weaknesses and disadvantages
Although they are perceived to have good environmental credentials waterborne polyurethane dispersions tend to suffer from lower mechanical strength than other resins. The use of polycarbonate based polyols in the synthesis can help overcome this weakness. The wear and corrosion resistance is also not as good and hence they are often hybridized. Other strategies used to overcome some of the weaknesses include molecular design and mixing/compounding with inorganic rather than polymeric materials. The use of an anionic or cationic center or indeed a hydrophilic non-ionic manufacturing technique tends to result in a permanent inbuilt water resistance weakness. Research is being conducted and techniques developed to combat this weakness. Simple blending has also been employed. This has the advantage in that if no new molecule has been formed but merely blending with existing registered raw materials, then that is a way around the work required to get registration of the material under various country regimes such as REACH in Europe and TSCA in the United States. Because of the surface tension of water being so high, pinholes and other problems of air-entrainment tend to be more common and need special additives to combat. They also tend not to be manufactured with biobased polyols because vegetable based polyols don't have performance enhancing functional groups. Modification is possible to achieve this and enable even greener versions.
Drying, curing and cross-linking is also not usually as good and hence research is proceeding in the area of post crosslinking to improve these features.
Hybrids
The disadvantages of PUDs are being improved by research. Hybridization using other materials and techniques is one such area. PUDs that are waterborne and UV curable are being intensely researched with well over 100 research papers produced in the 2000-2020 time period. Waterborne PUD- Acrylates based on epoxidized soybean oil that is also UV curable have been produced and are feasible. The nature of the acrylate affects the properties. One use of hybrids is in textile finishes.
As ionic centers are introduced with waterborne PUDs, the water resistance and uptake in the final film has been studied extensively. The nature of the polyol and the level of COOH groups and hydrophobic modification with other moieties can improve this property. Polyester polyols give the biggest improvements. Polycarbonate polyols also enhance properties, especially if the polycarbonate is also fluorinated. Reinforcing PUDs with nanomaterials also improves properties, as does silicone modification.
To make PUDs more hydrophobic and water repellent and thus remove a weakness, a number of techniques have been researched. One way is to add hydroxyethyl acrylate to the polyol reacting with isocyanate. Once the PUD is made it will have terminal double bond functionality from the acrylate. This may now be copolymerized with a very hydrophobic acrylate such as stearyl acrylate using free radical techniques. This long alkyl chain introduced confers hydrophobicity.
Another method of hybridization is to make a PUD that is both anionic but with a very substantial nonionic modification utilizing a polyether polyol based on ethylene oxide. In addition, a silicone diol maybe incorporated.
As epoxy resins have some outstanding properties, research using epoxy to modify PUD is taking place.
PUDs that are based on thiol rather than hydroxyl and also modified with both acrylate as well as epoxy functionality have been produced and researched.
As PUDs are resin dispersed in water, when cast as a film and dried they are inherently high gloss. They can be designed to be matte/flat by incorporating siloxane functionality.
Since PUDs are usually considered green and environmentally friendly, techniques being researched also include capturing carbon dioxide from the atmosphere to make the raw materials and then further synthesis.
See also
Coatings
Polymer science
Synthetic resin
Water
Waterborne resins
References
External links
Alberdink and Boley Website
Lubrizol website
Mitsui
American General Info
BASF
Perstorp Range
Incorez range
Halox includes formulations
DOW literature with overview
Plastics
Wood finishing materials
Adhesives
Coatings
Elastomers
Polymer chemistry
Synthetic resins | Polyurethane dispersion | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 2,028 | [
"Synthetic resins",
"Synthetic materials",
"Coatings",
"Unsolved problems in physics",
"Materials science",
"Elastomers",
"Polymer chemistry",
"Amorphous solids",
"Plastics"
] |
58,220,029 | https://en.wikipedia.org/wiki/Reppie%20waste-to-energy%20plant | The Reppie waste-to-energy plant is a waste-to-energy plant in Addis Ababa, Ethiopia, which treats waste from the city. The plant was developed by Cambridge Industries Ltd for Ethiopian Electric Power and Addis Ababa City Administration. The facility was founded by Samuel Alemayehu to tackle waste in the city of Addis Ababa. The plant became operational in August 2018 making it the first waste-to-energy plant in Africa.
Overview
The Reppie waste-to-energy plant includes two combustion systems (MARTIN SITY 2000 reverse grates) with 2 waste cranes with a capacity of 2x700 ton/d = 1400 ton/d. The Reppie site is built on reclaimed land from an old landfill.
The sites include facilities to process household and commercial waste, using waste combustion to recover energy, biological treatment, re-use, recycling and landfill.
Gallery
References
Power stations in Ethiopia
Addis Ababa
Energy recovery
Power stations in Africa
Recycling
Facilities engineering
Plastic recycling
Insect farming | Reppie waste-to-energy plant | [
"Engineering"
] | 206 | [
"Building engineering",
"Facilities engineering",
"Mechanical engineering by discipline"
] |
58,221,056 | https://en.wikipedia.org/wiki/C23H29FN2O | {{DISPLAYTITLE:C23H29FN2O}}
The molecular formula C23H29FN2O may refer to:
4-Fluorobutyrfentanyl, opioid analgesic and analog of butyrfentanyl; has been sold online as a designer drug
4-Fluoroisobutyrfentanyl, opioid analgesic, analog of butyrfentanyl, and structural isomer of 4-Fluorobutyrfentanyl; has been sold online as a designer drug
XEN1101, an experimental anticonvulsant drug | C23H29FN2O | [
"Chemistry"
] | 131 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
58,221,265 | https://en.wikipedia.org/wiki/C23H28N2O | {{DISPLAYTITLE:C23H28N2O}}
The molecular formula C23H28N2O (molar mass: 348.48 g/mol) may refer to:
CUMYL-PICA (SGT-56)
Cyclopropylfentanyl
Iferanserin (VEN-309)
NMP-7
Molecular formulas | C23H28N2O | [
"Physics",
"Chemistry"
] | 79 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
58,221,419 | https://en.wikipedia.org/wiki/C24H32N2O2 | {{DISPLAYTITLE:C24H32N2O2}}
The molecular formula C24H32N2O2 (molar mass: 380.52 g/mol, exact mass: 380.2464 u) may refer to:
Eprazinone
4-Methoxybutyrfentanyl
R-30490 | C24H32N2O2 | [
"Chemistry"
] | 74 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
58,222,003 | https://en.wikipedia.org/wiki/Nigel%20R.%20Franks | Nigel R. Franks (born 21 August 1956) is an English emeritus professor of Animal Behaviour and Ecology at the University of Bristol. He obtained a BSc and PhD in biology at the University of Leeds. After receiving his BSc in 1977 he began his PhD, during which he spent two years doing field work in Panama on army ants with the Smithsonian Tropical Research Institute. He was awarded the Thomas Henry Huxley Award in 1980 from the Zoological Society of London for the best British PhD in Zoology. He then received a Postdoctoral Fellowship from the Royal Commission for the Great Exhibition of 1851 allowing him to undertake postdoctoral work under Edward O. Wilson at Harvard University before becoming a lecturer at the University of Bath in 1982, later being promoted to full professor in 1995. He moved to the University of Bristol in 2001. He is renowned for his studies of collective animal behaviour, particularly of ant colonies. His Ant Lab at Bristol pioneered the use of Temnothorax (Temnothorax albipennis) as a model ant species for the study of collective decision-making and complex systems. In a 2009 profile in Science he discusses his pioneering use of radio-frequency identification tags (RFID) glued to the backs of each ant for tracking individuals in their society. His book Social evolution in ants with Andrew Bourke was an important contribution to the understanding of kin selection theory and sex ratio theory with respect to social evolution in insects, while his co-authored book Self-organization in biological systems has been cited well over 3000 times
Temnothorax albipennis ants have been observed teaching each other through a process known as tandem running. An experienced forager leads a naive nest-mate to a newly discovered resource such as food or an empty nest site. The follower obtains knowledge of the route by following in the footsteps of the tutor, maintaining contact with its antennae. Both leader and follower are aware of the progress made by the other with the leader slowing when the follower lags and speeding up when the follower gets too close. Depending on how far away a new resource is, colonies will modulate the number of tandem runs that they perform, with a greater number of tandem runs occurring when the desired resource is more distant. Furthermore, the relative contribution that workers make to this process differs widely among individuals, with certain ants attempting many more tandem runs than others.
References
1956 births
Living people
Ethologists
Alumni of the University of Leeds
Academics of the University of Bath
Academics of the University of Bristol | Nigel R. Franks | [
"Biology"
] | 502 | [
"Ethology",
"Behavior",
"Ethologists"
] |
58,222,565 | https://en.wikipedia.org/wiki/Thomas%20H.%20Haines | Thomas Henry Haines (August 9, 1933 – December 17, 2023) was an American author, social activist, biochemist and academic. He was a professor of chemistry at City College of New York and of Biochemistry at the Sophie Davis School of Biomedical Education. He was a visiting professor in the Laboratory of Thomas Sakmar at Rockefeller University. He also served on the board of the Graham School, a social services and foster care agency in New York City. His scientific research focused on the structure and function of the living cell membrane. He is the father of Avril Haines, the seventh Director of National Intelligence.
Early life and education
Thomas Haines was born on August 9, 1933, to Elsie Cubbon Haines (1894–1955) and Charles Haines, who deserted when Haines was two. In 1937, "by reason of the insanity of the mother", a judge placed him at the Graham School, an orphanage in Hastings-on-Hudson, New York. The orphanage, now a social services and foster care agency, was founded in 1806 by Isabella Graham and Elizabeth Hamilton, the recently widowed wife of Alexander Hamilton. Haines remained at the orphanage until high school, when he became a resident houseboy and gardener for a wealthy Hastings family. The story of Haines' early life appears as "From the Orphanage to the Lab" in the Story Collider podcast. and in his autobiography with Mindy Lewis, A Curious Life: From Rebel Orphan to Innovative Scientist.
Haines attended the City College of New York, with a B.S. in chemistry in 1957 and an M.S. in education in 1959. During that time he worked as live-in baby sitter for then-blacklisted American songwriter Jay Gorney (co-writer with Yip Harburg of the Depression era anthem, “Brother, Can You Spare a Dime?”) and his wife Sondra. There Haines came to know many other blacklisted professionals including actors Zero Mostel, Paul Robeson, and Lionel Stander, philosopher Barrows Dunham, and Bella Abzug, then a young lawyer defending blacklisted artists and intellectuals at HUAC hearings.
Career
After CCNY, Haines taught elementary school science at the Ethical Culture Fieldston School. He then became a laboratory assistant to Richard Block at the Boyce Thompson Institute where he studied the microorganism Ochromonas danica. When Block died in a plane crash, Haines took over his research projects. In 1964 he obtained his Doctor of Philosophy degree in chemistry from Rutgers University.
Haines became assistant professor of chemistry at City College in 1964 and full professor of chemistry in 1972, a position he held until retiring in 2007. In 1972 he co-founded the Sophie Davis School of Biomedical Education with University President Robert Marshak. This remarkable program took new undergraduates directly into medical school. It continues today as The CUNY School of Medicine. Haines taught biochemistry to undergraduates and served as director of biochemistry at the school from 1974 to 2006. Deeply committed to his students, he also taught remedial summer school and regularly counseled struggling students and their parents. On many occasions he was voted most popular professor.
Haines simultaneously conducted laboratory research and taught as professor of biochemistry in the doctoral program of biochemistry at the Graduate Center of the City University of New York. He has published extensively on the structure and function of living membranes, including on the function of cholesterol in blocking sodium leakage through membranes, and most recently on the function of cardiolipin in the mitochondrial membrane.
From 1994 to 2001, Haines chaired the Partnership for Responsible Drug Information, which organized lectures and conferences to educate the public about alternatives to the "War on Drugs."
Haines served as visiting professor at the Mitsubishi Institute in Japan, at the University of California at Berkeley, and in many other universities. On his retirement from CCNY, he became a visiting professor of biochemistry at the Sakmar Laboratory at Rockefeller University.
In 2020, Haines was elected a Fellow of the American Association for the Advancement of Science "For initiating and setting up the CUNY Medical School at City College of New York to educate minority and disadvantaged students."
Personal life
In 1960, Haines married painter Adrienne Rappaport, who used the name Adrian Rappin professionally. They had one daughter, Avril Haines, an attorney who is serving as the current Director of National Intelligence in the Biden administration. Rappaport died in 1985 after developing chronic obstructive pulmonary disease and later contracting avian tuberculosis.
In 1986, Haines married his current wife, economist Mary "Polly" Cleveland.
In 1964, Haines and Rappaport purchased two small run-down rent-controlled apartment buildings on New York's Upper West Side for $140,000, $10,000 down and for a time employed Al Pacino as the building superintendent.
When Haines and Cleveland sold the buildings for many millions of dollars in 2009, they put half the net proceeds into a foundation for the benefit of scientific and economic education.
Haines died in New York on December 17, 2023, at the age of 90.
External links
References
1933 births
2023 deaths
American biochemists
City College of New York alumni
City College of New York faculty
Cornell University staff
Rutgers University alumni
CUNY Graduate Center faculty
People from New York (state)
Biochemistry educators
20th-century American biochemists
Membrane proteins | Thomas H. Haines | [
"Chemistry",
"Biology"
] | 1,105 | [
"Biochemistry",
"Membrane proteins",
"Protein classification",
"Biochemistry educators"
] |
58,223,172 | https://en.wikipedia.org/wiki/Flag%20bundle | In algebraic geometry, the flag bundle of a flag
of vector bundles on an algebraic scheme X is the algebraic scheme over X:
such that is a flag of vector spaces such that is a vector subspace of of dimension i.
If X is a point, then a flag bundle is a flag variety and if the length of the flag is one, then it is the Grassmann bundle; hence, a flag bundle is a common generalization of these two notions.
Construction
A flag bundle can be constructed inductively.
References
Expo. VI, § 4. of
Algebraic geometry | Flag bundle | [
"Mathematics"
] | 116 | [
"Fields of abstract algebra",
"Algebraic geometry"
] |
58,226,562 | https://en.wikipedia.org/wiki/Lipase%20a%2C%20lysosomal%20acid%20type | Lipase A, lysosomal acid type is a protein that in humans is encoded by the LIPA gene.
Function
This gene encodes lipase A, the lysosomal acid lipase (also known as cholesterol ester hydrolase). This enzyme functions in the lysosome to catalyze the hydrolysis of cholesteryl esters and triglycerides.
Mutations in this gene can result in Wolman disease and cholesteryl ester storage disease. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jan 2014].
References
Further reading | Lipase a, lysosomal acid type | [
"Chemistry",
"Biology"
] | 130 | [
"Biochemistry stubs",
"Biotechnology stubs",
"Biochemistry"
] |
63,459,562 | https://en.wikipedia.org/wiki/NGC%20802 | NGC 802 is a lenticular galaxy in the constellation Hydrus. It is about 68 million light-years from the Milky Way and has a diameter of about 20,000 light years. NGC 802 was discovered on November 2, 1834 by the British astronomer John Herschel.
See also
List of NGC objects (1–1000)
References
Lenticular galaxies
Hydrus
0802
007505 | NGC 802 | [
"Astronomy"
] | 82 | [
"Hydrus",
"Constellations"
] |
63,460,022 | https://en.wikipedia.org/wiki/NGC%20803 | NGC 803 is a spiral galaxy located in the constellation Aries about 70 million light-years from the Milky Way. It was discovered by the German–British astronomer William Herschel in 1784.
See also
List of NGC objects (1–1000)
Gallery
References
External links
0803
Unbarred spiral galaxies
Aries (constellation)
007849 | NGC 803 | [
"Astronomy"
] | 73 | [
"Aries (constellation)",
"Constellations"
] |
63,460,177 | https://en.wikipedia.org/wiki/NGC%20804 | NGC 804 is a lenticular galaxy located in the Triangulum constellation about 231 million light-years from the Milky Way. It was discovered by the American astronomer Lewis Swift in 1885. This galaxy was also observed by the French astronomer Guillaume Bigourdan on December 24, 1897, and it has been added to the Index Catalogue under the symbol IC 1773.
See also
List of NGC objects (1–1000)
References
External links
0804
IC objects
Triangulum
Lenticular galaxies
007873 | NGC 804 | [
"Astronomy"
] | 104 | [
"Triangulum",
"Constellations"
] |
63,460,433 | https://en.wikipedia.org/wiki/NGC%20781 | NGC 781 is a spiral galaxy in the constellation Aries. It is estimated to be about 154 million light years from the Milky Way and has a diameter of approximately 70,000 light years. NGC 781 was discovered on October 16, 1784 by the German-British astronomer William Herschel.
See also
List of NGC objects (1–1000)
References
External links
Aries (constellation)
0781
Spiral galaxies
007577 | NGC 781 | [
"Astronomy"
] | 89 | [
"Aries (constellation)",
"Constellations"
] |
63,460,570 | https://en.wikipedia.org/wiki/NGC%20782 | NGC 782 is a barred spiral galaxy located in the constellation Eridanus about 160 million light-years from the Milky Way. It was discovered by British astronomer John Herschel in 1834.
A type Ia supernova designated SN 2011eb was discovered in this galaxy on July 9, 2011. It was positioned west and south of the galactic core.
References
0782
Barred spiral galaxies
Eridanus (constellation)
007379 | NGC 782 | [
"Astronomy"
] | 89 | [
"Eridanus (constellation)",
"Constellations"
] |
63,460,742 | https://en.wikipedia.org/wiki/Primary%20Industries%20and%20Regions%20SA | Primary Industries and Regions SA (PIRSA), also known as Primary Industries and Regions South Australia, and the Department of Primary Industries and Regions SA, is an agency of the South Australian Government whose focus is the economic development of the state of South Australia. Its key areas of work include primary sector industries (in South Australia, mainly farming), and biosecurity.
Description
The purpose of the agency is to "grow primary industries and drive regional development". Its key areas of work include primary sector industries (in SA, mainly agriculture, viticulture and farming of livestock), marine aquaculture, and biosecurity. Agribusiness, covering "food and beverage, field crops, meat and livestock, wine, seafood, horticulture and forestry sectors" are seen as mainstays and growth areas of the South Australian economy.
Along with the South Australian Research and Development Institute (SARDI), PIRSA has been located at the Waite Research Precinct, alongside the University of Adelaide's Waite campus since about 1994.
The Fisheries and Aquaculture division manages the state's fish stocks, along with industry and the community, by developing and implementing policy and regulations to ensure sustainable development of the aquaculture industry. It employs fisheries officers to monitor compliance with fishing regulations.
PIRSA runs a grants program for farm industry business owners and operators.
SARDI is the state government's principal research institute, and forms part of PIRSA.
Organisational history
In 1992, the South Australian Department of Agriculture, the Department of Fisheries, and the Department of Woods and Forests merged to form Primary Industries South Australia (PISA). In 1996–1997, the name of Mines and Energy South Australia was changed to Mines and Energy Resources South Australia (MERSA).
In 1997, PISA and MERSA merged to form Primary Industries and Resources SA, formally the Department of Primary Industries and Resources SA (PIRSA). In 2011–12 the name was changed to Primary Industries and Regions SA.
In 2019, the Pastoral Board of South Australia, which governs pastoral leases in South Australia, moved to PIRSA from the Department for Environment and Water.
In 2019, PIRSA and SARDI also entered a partnership with the University of Adelaide in which scientists in diverse disciplines were to be able to access PIRSA's research farms and share their academic knowledge to the agricultural sector. The collaboration was anticipated to help develop SA's expertise in dryland agriculture by encouraging multi-disciplinary research and helping to bring about new export opportunities.
Biosecurity Act upgrade
In 2020, PIRSA started a review of biosecurity legislation in South Australia, which had been covered by several pieces of legislation; the aim was to achieve a single Act for the state that would ensure South Australia's biosecurity systems remain effective. , the Bill was expected to progress through the parliamentary process by the end of the year.
Examples of PIRSA's work
In 2007, as part of its community program, PIRSA administered a travel survey in Adelaide that identified the need for secure parking for bicycles in the city. A parking station for 21 bikes was built in a basement at the Grenfell Centre, which proved very popular. It also established a bicycle user group.
PIRSA fisheries officers police fishers' compliance with fisheries regulations to ensure fish stocks are safeguarded for future generations. An example in December 2014 was when fisheries officers caught two men fishing at Wallaroo for snapper during the annual closure period. The men fled and were detained away. The fishers were fined and ordered to pay costs totalling .
To help with landholders' recovery from the December 2019 bushfires, PIRSA prepared, with other agencies, an impact assessment of the damage done to many types of agricultural enterprises. Advice on caring for stock, coordination of various types of assistance, and technical support were given to people who had suffered losses from the fires, many of whom were located around Cudlee Creek and on Kangaroo Island.
References
External links
Agriculture in South Australia
Biosecurity
Government agencies of South Australia
Primary industry departments in Australia | Primary Industries and Regions SA | [
"Environmental_science"
] | 828 | [
"Toxicology",
"Biosecurity"
] |
63,463,276 | https://en.wikipedia.org/wiki/Redmi%20K30%20Pro | Redmi K30 Pro is a line of Android-based smartphones manufactured by Xiaomi and marketed under its Redmi sub-brand. There are four models, the K30 Pro, K30 Pro Zoom, K30 Ultra and the POCO F2 Pro, which is a rebranded version of the K30 Pro.
The company discontinued the smartphone's sale in favor of the successor Redmi K40 Pro lineup in 2021.
Design
The K30 Pro line uses an anodized aluminum frame and Gorilla Glass on the front and back. Both the volume and power buttons are located on the right edge; the latter has a red accent. The front-facing camera is concealed by a motorized pop-up mechanism like on the K20 Pro. The camera protrusion on the back panel is a single unit with a dual-LED flash below, and a circular module. Colors available at launch were (Cyber) Grey, (Electric) Purple, (Phantom) White and (Neon) Blue. The K30 Ultra has unique Moonlight White, Midnight Black and Mint Green finishes.
Specifications
Hardware & software
The Pro models are powered by the Snapdragon 865 and Adreno 650, while the K30 Ultra uses the MediaTek Dimensity 1000+ and Mali-G77 MC9. The K30 Pro, K30 Pro Zoom and POCO F2 Pro have either 128 or 256 GB of storage and 6 or 8 GB of RAM with an additional 12 GB RAM/512 GB UFS variant on the K30 Pro Zoom; the 128 GB/6 GB K30 Pro model has UFS 3.0 while other models have UFS 3.1. The POCO F2 Pro has UFS 3.1 on all models and no 8 GB RAM/128 GB UFS variant. At the front, the display is larger than the K20's at 6.67" (169.4mm) and has a wider 20:9 aspect ratio, using an AMOLED panel with an optical fingerprint sensor and HDR10+ support; only the K30 Ultra has a 120 Hz refresh rate. The battery is 4700mAh; fast charging is supported over USB-C up to 30 W or 33 W. The K30 Ultra has a smaller 4500 mAh battery. All devices are pre-installed with MIUI 11, which is based on Android 10. Among other features, there is FM Radio, Dual SIM support, NFC, Infrared, Face Unlock, and LiquidCool 2.0 in the phone.
Xiaomi released another version of the phone, Redmi K30 Pro Zoom, with almost similar features except 3x optical zoom.
Camera
The wide sensor on all variants has been upgraded from a Sony IMX586 48 MP sensor to a Sony IMX686 64 MP sensor and now features an extra depth sensor. The K30 Pro Zoom benefits from the usage of optical image stabilization on the wide lens. It has an 8 MP telephoto lens with 3x optical zoom, while the K30 Pro and POCO F2 Pro have a 5 MP "telemacro" lens which has twice the focal length of a standard macro lens. Both are accompanied by a 13 MP ultrawide sensor. The front-facing camera uses a motorized pop-up Samsung S5K3T2 20 MP sensor, f/2.2, (wide), 1/3.4", 0.8 μm with HDR.
References
Phablets
Mobile phones introduced in 2020
Mobile phones with multiple rear cameras
Mobile phones with 8K video recording
Mobile phones with infrared transmitter
Discontinued flagship smartphones
K30 Pro | Redmi K30 Pro | [
"Technology"
] | 743 | [
"Phablets",
"Crossover devices",
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
63,463,389 | https://en.wikipedia.org/wiki/Polish%20bed | A Polish bed (; ), alternatively known in English as a polonaise, is a type of small-canopy bed which most likely originated in Poland and became a centrepiece of 18th-century French furniture. The curtain is topped with an elaborate crownlike centrepiece, which is connected to the four vertical corner poles of the bed frame (which are usually curved). Unlike the four-poster bed, the canopy is much smaller than the bed.
Historically, a Polish bed was often placed on its side against the wall to serve as a daybed. Nowadays, any type of curtained daybed or couch is known under this term. The Polish bed shares many similarities with the lit à la turque, however Turkish-styled beds contain two scrolling ends and the canopy is generally off-center, and suspended from one side only.
Polonaise bedding was possibly first observed at the Royal Castle in Warsaw, at the time when Ottoman styles were fashionable across Europe. They were popularized in France by Polish-born queen Marie Leszczyńska, who married Louis XV of France in 1725. Hence, it became a principal piece of the so-called Louis XV furniture. These richly decorated rococo beds were generally designated for the wealthier upper classes and aristocracy that resided in palaces, however, canopies were also popular in many common homes (the warmth of the curtains was functional). The French propagated the design as lit à la polonaise.
Polish beds dating back to the period can be found in museums, most famous being the Palace of Versailles in France. The polonaise should not be confused with the lit à la Duchesse where the canopy is only supported from one end.
Gallery
References
Beds
Sleep
Rococo art
Interior design
Louis XV
History of furniture | Polish bed | [
"Biology"
] | 360 | [
"Beds",
"Behavior",
"Sleep"
] |
63,464,189 | https://en.wikipedia.org/wiki/Impact%20of%20the%20COVID-19%20pandemic%20on%20the%20video%20game%20industry | The video game industry has been substantially impacted by COVID-19 pandemic restrictions in various ways, most often due to concerns over travel to and from China or elsewhere, and delays in the manufacturing processes within China.
Overview
In contrast to many other economic sectors that are drastically affected by the pandemic restrictions, the video game industry has been more resilient. Most video game developers, publishers, and operators have been able to maintain operations with employees remote working to sustain game development and digital releases, though some productivity issues arose. With many people globally at home and unable to work, online gaming has observed record numbers of players during the pandemic as a popular activity to counter physical distancing for society, a practice recommended by the World Health Organization that helped boost revenues for many companies in the gaming industry.
There have still been negative impacts on the industry, notably with major trade events like E3 2020 cancelled or postponed which may have impacted relationships between the smaller developers and publishers. This has particularly impacted indie developers who typically use these events for face-to-face meetings with potential partners to gain funding and publishing support, and caused them to have to delay or cancel projects. Many esport leagues had to alter plans for their games, transitioning from live events to remote play or cancellation altogether. Portions of the sector that relied on physical products, such as retail stores and peripheral makers, as well as those dependent on in-person activities such as quality assurance through playtesting, ratings evaluation, and marketing, also struggled with global stay-at-home orders.
As the origin of the pandemic, China was expected to impact the supply chains for electronics, which may limit hardware availability once the pandemic begins to be resolved. However, it did not impact plans for Microsoft and Sony to release the Xbox Series X and PlayStation 5 respectively in fall 2020.
Affected industry events
Many trade events and expositions for the industry were cancelled or postponed due to bans against public gatherings during the pandemic. The pandemic led to some longer term changes in the way the industry handled public outreach, such an increasing its reliance on digital marketing. The increasing importance of Nintendo Direct streams are an example of this.
Discontinued
Electronic Entertainment Expo, also known as E3, was discontinued as a result of the pandemic. E3 2020 was cancelled by March that year. Additional events were arranged to substitute for the trade event, such as Geoff Keighley's Summer Game Fest. E3 2021 was initially scheduled as normal as an in-person event with virtual elements, but the in-person event was cancelled in February 2021 in favor of a digital event only. The event was not held again.
Minecon was last held in 2016 but scheduled to return in 2020 as "Minecraft Festival". After several delays the in-person version was discontinued, though the online only event Minecraft Live which began in 2017 has continued to run.
IgroMir 2020 and 2021 were cancelled, and the organisers faced a lawsuit over non-refunded fees. The organisers then "went silent" following the Russian invasion of Ukraine, meaning that the event was not held again after 2019.
Comic-Con Russia had been formerly held alongside IgroMir, so the cancellation of the parent event also discontinued Comic-Con Russia.
Delayed or cancelled
The 2020 Vancouver Retro Gaming Expo in New Westminster was postponed until 25 June 2022.
The Taipei Game Show, planned from 6–9 February 2020, was postponed until 25–28 June 2020, but was cancelled in March 2020 due to pandemic's escalation.
The Mobile World Congress, to have been held in Barcelona, Spain, in March 2020 was cancelled as several of the China-based vendors had to cancel plans.
The 16th British Academy Games Awards, normally presented at a ceremony in London, were moved to a live streamed event due to concerns over the pandemic.
Paris Games Week, planned for 23–27 October 2020, was cancelled.
Insomnia66, set to take place 10–13 April 2020 at the NEC, Birmingham was cancelled in March 2020
COMPUTEX Taipei 2020, planned for 2–6 June 2020, was postponed to 28–30 September 2020, but was cancelled in June 2020.
The 2020 BlizzCon was cancelled.
Brasil Game Show 2020, which was planned for 8–12 October 2020, was cancelled.
South by Southwest in Austin, Texas, was cancelled, though the SXSW Gaming Awards were still awarded though an online announcement in March 2020.
Emerald City Comic Con planned for Seattle, Washington, in March was cancelled.
TwitchCon Europe and TwitchCon US were cancelled.
The 25th QuakeCon event, planned for Dallas, Texas in August.
San Diego Comic-Con, planned for July 2020, was cancelled.
The 17th annual Touhou Project dōjinshi convention (Reitaisai) planned in Tokyo, Japan, first planned on 22 March 2020, was postponed until 17 May, before being cancelled on 12 April, five days following the initial announcement of a state of emergency made by the Japanese government.
Comiket 98, a dōjinshi convention held in Japan, was cancelled.
PAX West 2020, originally scheduled for 4–7 September 2020 and PAX Australia 2020, originally scheduled for 9–11 October 2020, collaborated with EGX to host PAX Online x EGX Digital, which was held 12–20 September 2020.
The 2021 Japanese Amusement Expo (JAEPO) was cancelled in an 1 October 2020's announcement.
Super MAGFest 2021 was initially planned to be made virtual, but also cancelled.
Gamescom Asia's inaugural event was postponed to 2021.
Reduced in scope or made virtual
Several vendors withdrew or scaled plans back to present at PAX East in Boston at the end of February 2020, including Sony Interactive Entertainment, Square Enix, Electronic Arts, Capcom, CD Projekt, and PUBG Corporation.
Several companies pulled out from the Game Developers Conference (GDC) in San Francisco in March 2020, forcing the organizers to postpone the show to later in the year. However, the event organizers devised a scheme to run the GDC as a virtual conference following a similar schedule across the same set of days by using the streaming services with a subset of the planned events that are presented through the streaming media and was made available online a week later. This included the Game Developers Choice Awards and Independent Games Festival presentations.
Gamescom 2020 was held online.
Tokyo Game Show that was scheduled to run 24–27 September 2020, was cancelled, though online events were held in its place.
EGX 2020, planned for 17–20 September 2020, was cancelled, though online events were held 12–20 September 2020.
MAGWest 2020 and 2021 were both held virtually.
TennoCon 2020 and 2021 were conducted virtually.
2020 Gaming Community Expo scheduled for Orlando, Florida, in June was cancelled. The event moved online as a charity marathon.
Esports
Most esports events are based on online games, but are typically played in local arenas to reduce network latency between players as well as to provide an audience. The pandemic caused many of these events to either become cancelled or switch to a fully online format for 2020:
ESL Pro League Season 11, a Counter-Strike: Global Offensive tournament was originally going to be an offline event with the finals taking place at Denver, Colorado, United States. However, due to the pandemic, ESL announced that both the regular season and the finals would be split into two regions: Europe and North America. The regular season and the finals were played entirely online.
The competitions for non-rhythm games of the ninth season of Konami Arcade Championships (KAC), which were to be held from 22 and 24 February at e-sports GINZA Studio, were postponed indefinitely. This did not affect the competitions within Konami's Bemani rhythm games, as they were held earlier that month at the Japan Amusement Expo. On 16 December, Konami announced that the tenth season in 2021 would restrict participation to Japanese players only instead of worldwide as it has been traditionally done since 2012 (which include South Korea, Asia and United States), as a result of the travel restrictions set by the Japanese government; in addition, the finals that were to be held on 6 and 7 March 2021, would be in the GINZA Studio, behind closed doors. On 7 January 2021, Konami extended the qualifying period for the 10th tournament indefinitely while the finals were postponed. On 8 February 2021, Konami announced the 9th tournament would be cancelled. On 22 March 2021, a day after the state of emergency was lifted, the qualifier rounds were announced to end on 20 April.
闘神祭2020 (Tōshinsai), a cross-arcade game tournament held in Japan that is co-organised by NTT-esports and Taito, was cancelled. The finals initially scheduled from 16–17 May were postponed to 8–9 August.
The Overwatch League, in its 2020 season and third overall, planned to implement a home/away approach to regular season play similar to professional sports, with teams travelling across the globe to various homestand events for matches. With the pandemic, numerous changes to the league's plans had to be implemented, which included switching to online matches, reworking the teams' distributions in divisions as some teams were forced to suspend operations, cancelling certain mid-season events, and otherwise reducing the planned schedule of play. During the 2021 season, there were limited homestands by the Chinese teams and Dallas Fuel. To reduce latency during interregional tournaments, teams from the West division (North America and Europe) travelled to the University of Hawaiʻi at Mānoa, as they could connect to a Tokyo-based game server via an undersea communications cable link. The playoffs and finals were originally scheduled to be held as live events in Los Angeles and Arlington respectively, but it was cancelled and replaced with the same remote format as earlier due to COVID-19 and Delta variant concerns.
The League of Legends Rift Rivals and Mid-Season Invitational tournaments were cancelled, with the latter being replaced with the 2020 Mid-Season Streamathon, while 2020 World Championship would be played exclusively in Shanghai using the "isolation bubble" environment. In addition, majority of regional leagues, including League of Legends Championship Series and the League of Legends European Championship were either played in arenas without audience or switched to online formats. Due to national travel restrictions, esports teams of Vietnam Championship Series could not participate in the 2020 World Championship and 2021 Mid-Season Invitational.
NACE was forced to suspend play until April 13, 2020, on March 16, 2020.
The 2020 Pokémon World Championships was cancelled by The Pokémon Company including its North American (scheduled for 26–28 June) and global (scheduled for 14–16 August) events.
The 2020 Nürburgring World Tour, a live event of the 2020 FIA-Certified Gran Turismo Championships season, was cancelled after the 2020 Nürburgring 24 Hours was postponed by the organizers to September. As the online season had begun on 17 March, the decision was made to change the stage that was planned to end on 18 April an "exhibition stage", and to restart the season on 25 April. A teaser trailer for the restarted season indicated that no further live events would be held, having held only one live event in Sydney, Australia. Consequently, the regional and world finals for the series were held as online-based events.
The live Rocket League World Championship for its 9th season, planned for 24 April 2020 in Dallas, was indefinitely postponed.
The 2020 Fortnite World Cup was cancelled.
The International 2020 tournament for Dota 2, set to be held in Stockholm in August 2020, was postponed indefinitely before being pushed back a year and rebranded as The International 2021. That event was to be held with in-person spectators in Bucharest, Romania, in October 2021, but due to new COVID-19 restrictions in the city, it was announced that the event would instead be played behind closed doors at the stadium with only essential personnel present.
Evo 2020, set to be held in Las Vegas near the end of July, was cancelled. Online events were scheduled before the entire tournament was cancelled due to sexual abuse allegations against its co-founder. Evo Online was held in 2021, with its announcement concurrent with the acquisition of Evo by Sony Interactive Entertainment and Endeavor. It was later announced that the top players at Evo Online would compete at an in-person "Evo Showcase" event at UFC Apex in Las Vegas (owned by Endeavor subsidiary Ultimate Fighting Championship) in November. However on 29 September 2021, Evo announced that Evo Showcase had been cancelled due to COVID-19-related concerns (including Delta variant).
Mobile Legends: Bang Bang Southeast Asia Cup (MSC) 2020, set to be held in Philippines on 12–14 June 2020, was cancelled.
Arena of Valor World Cup 2020, set to be held in Vietnam, was cancelled.
Free Fire Champions Cup 2020, set to be held in Indonesia in April 2020; and Free Fire Worlds Series 2021, set to be held in Mexico, were cancelled.
The Asia-Pacific Predator League 2020 was postponed to Spring 2021. All of the qualifying teams during the event were to participate in the finale in 2021.
The Teppen World Championship 2020 was held entirely online. Offline tournaments meant to qualify players to the finals were cancelled due to the pandemic.
While many traditional physical sports games, seasons, and playoffs were cancelled due to the pandemic, the organizing leagues turned to video game equivalents as alternative entertainment, using the professional athletes from their leagues within the games. Some examples of this included:
NASCAR launched its eNASCAR iRacing Pro Invitational Series on 22 March 2020, featuring NASCAR drivers competing using the iRacing game. The IndyCar Series launched its own IndyCar iRacing Challenge series as well.
Major League Baseball partnered with Sony to create a short league for 30 professional players playing MLB: The Show.
The 2021 Pro Bowl for the National Football League, to have taken place in January 2021, was cancelled due to COVID-19, with the NFL opting to use a virtual game in Madden NFL 21 to celebrate the players selected by fans.
Television networks which normally would have shown the sporting events that were cancelled have turned to both these replacement sports programs as well as other esport tournaments as replacement programming during the pandemic. On 14 June 2020, the BBC reported that about 22 million sports viewers turned to virtual races when lockdowns were implemented. Questions over the future of esports rose with Formula 1 returning in July 2020.
Hardware production
Nintendo Switch production in Vietnam had been scaled back due to reduced supply of components out of China because of the quarantines. As a result, supplies for the Switch were significantly reduced in Japan. In its annual report issued in May 2020, Nintendo believed that production would resume normal levels within a few months. Further, Nintendo of America closed its repair center as a preventative measure. The company's headquarters in Redmond, Washington, and the flagship store in New York City were also closed.
Valve announced that its production on the Valve Index virtual reality headset was reduced due to the impact of the pandemic and would have fewer shipments expected than planned by the release of Half-Life: Alyx.
Konami delayed release of the TurboGrafx-16 Mini in March due to production chain issues in China due to the pandemic.
Atari delayed the Atari VCS that was initially supposed to release in March 2020 because of the pandemic.
Microsoft did not anticipate any delay in the planned release of the Xbox Series X console, according to Phil Spencer . He stated that some games expected near launch may be delayed as a result.
The Evercade handheld console, originally due to release on May 22, 2020, released sometime between May 22, and June 5, 2020.
Nvidia's GeForce 30 series of graphics cards immediately sold out upon their release, due largely to a rise in consumer demand for computer hardware during the pandemic, as well as a lack in proper security against scalpers.
Sales
Generally, sales of video games have increased as a result of stay-at-home and lockdown orders from the pandemic, as people turned to video games as a pastime. The NPD Group reported that video game sales in North America in March 2020 were up 34% from those in March 2019, and video game hardware up by 63% – which included more than twice the number of units of the Nintendo Switch console. Net spending across the first quarter of 2020 in the United States reached , up 9% in 2020 compared to 2019 according to NPD. An increase at this point, near the planned end of the eighth generation of video game consoles, was unusual and was attributed to the pandemic. By July 2020, NPD Group reported that the total sales of video game hardware and software within the United States in the first six months of 2020 reached , the highest since 2010.
Some specific examples of game software and hardware sales affected by the pandemic include:
The 2012 game Plague Inc. by Ndemic Creations had a significant increase in sales as a result of the pandemic. The game temporarily became the top-paid app on several regional app stores, beating out the perennial bestseller Minecraft. Some analysts believed that those worried about the pandemic used the game to see that it could spread as a means to placate their fears. While the game was based on scientific models of the spread of contagious diseases, Ndemic had to remind the players that the game was not meant to be taken as an accurate model for transmission and spread and referred those interested to the Centers for Disease Control and other national and international health organization websites. Ndemic later added a new gameplay mode to Plague Inc, with the goal to try to stop an ongoing pandemic through various possible options by using the work that it developed in coordination with WHO and the Global Outbreak Alert and Response Network. The company also donated to the Coalition of Epidemic Preparedness Innovations and the WHO COVID-19 Solidarity Response Fund to help fight the pandemic and encouraged the players of the game to do the same.
The 2018 digital adaption of Pandemic by Asmodee experienced an increase in sales.
Both Doom Eternal and Animal Crossing: New Horizons, major AAA titles released in March 2020, outperformed industry expectations, with Animal Crossing selling more in its opening week in the United Kingdom than all of the previous launches in the franchise combined for the same region.
Ring Fit Adventure, which involves physical activity, was in high demand in China as a result of the quarantine. Sales led to shortages and price gouging in East Asia and nearby regions. Similar shortages for the game expanded as quarantines and stay-at-home orders came to many Western locations during March 2020.
Coupled with lowered hardware production, the Nintendo Switch became a high-selling commodity during the pandemic, as it provided entertainment options across all ages, especially with Animal Crossing: New Horizons. Nintendo worked to supply as many units as possible globally to most markets, which led to some resellers using bots to scalp. The Switch's high sales helped to offset low sales of other console hardware within the United States and buoy higher revenues for the sector.
Among Us rose in popularity through Twitch after streamer Sodapoppin popularised it through the platform in late July 2020.
Minecraft Dungeons topped Animal Crossing on the North America eShop when they released their new DLC packs: Jungle Awakens and Creeping Winter. They also announced cross-platform features.
Software releases
An estimated one-third of developers surveyed in 2020 by the GDC stated that COVID-19 caused a delay of the games they were working on, a combination of the pandemic and the remote working conditions. By 2021, this had increased to 44% by 2021 in a subsequent GDC survey. Some games that were delayed included:
The Outer Worlds for Nintendo Switch from March 6 to June 5, 2020
Someday You'll Return from April 14 to May 5, 2020
Hellpoint from April 16 to July 30, 2020
Yumeutsutsu Re:Master and Yumeutsutsu Re:After for PlayStation Vita from April 23 to July 23, 2020. The PlayStation 4 versions were never delayed despite confirmation of such.
Minecraft Dungeons from April to May 26, 2020
Trackmania from May 5 to July 1, 2020
Marvel's Iron Man VR from May 15 to July 3, 2020
The Wonderful 101: Remastered physical edition from May 19 to June 30 in North America and May 22 to July 3, 2020, in Europe
Sword Art Online: Alicization Lycoris from May 21 to July 9 in Japan and May 22 to July 10, 2020, in North America
Is It Wrong to Try to Pick Up Girls in a Dungeon? Infinite Combat from early 2020 to August 7, 2020, in Europe and August 11, 2020, in North America
Ninjala from May 27 to June 24, 2020
Final Fantasy XIV Patch 5.3 from June 16 to August 11, 2020, as well as the game's fourth expansion pack, Endwalker, from Q3 2021 to December 7, 2021
Fairy Tail from June 25 to July 30, 2020, in Japan and Europe, and a day later in North America
E-School Life for Nintendo Switch and PS4 from June 25 to July 30, 2020, in Japan
Fast & Furious Crossroads from May to August 7, 2020
Kiss Trilogy for PS4 and Nintendo Switch from June 25 to August 27, 2020, in Japan
Kingdom Hearts: Dark Road from early 2020 to June 22, 2020
No Straight Roads from June 30 to August 25, 2020
Ary and the Secret of Seasons from July 28 to September 1, 2020
Death Stranding for PC from June 2 to July 14, 2020
Wasteland 3 from May 19 to August 28, 2020
The Last of Us Part II from May 29 to June 19, 2020
Ghost of Tsushima from June 26 to July 17, 2020
Monster Hunter World: Iceborne: Title Update 4 from May to July 9, 2020
Little Witch Academia: VR Broom Racing from June to late 2020 for Oculus Quest and early 2021 for PlayStation VR, Oculus Rift and SteamVR
Rock of Ages 3: Make & Break from June 2 to July 21, 2020
Star Wars Episode I: Racer Remaster for Nintendo Switch and PS4 from May 12 to June 23, 2020
Phogs! from June to December 3, 2020
The Dark Pictures Anthology: Little Hope from mid-2020 to October 30, 2020
Mafia: Definitive Edition from August 28 to September 25, 2020
Stronghold: Warlords from September 29, 2020, to January 9, 2021, and then finally released at March 9, 2021, after further delays due to problems in the game's multiplayer mode.
Blue Fire for PS4, Xbox One and PC from mid-2020 to Q1 2021
Kerbal Space Program 2 from early 2020/Q3 2021 and then to 2022 and finally into early 2023.
Guilty Gear Strive from late 2020 to June 11, 2021.
Warframe Major Update called Duviri Paradox from 2020 to 2021
Halo Infinite from 2020 to December 8, 2021
Deathloop from 2020 to September 14, 2021
The Stanley Parable: Ultra Deluxe from 2020 to April 27, 2022
Sky: Children of the Light for Nintendo Switch from 2020 to June 29, 2021
No More Heroes III from 2020 to August 27, 2021
Kena: Bridge of Spirits from 2020 to September 21, 2021
Outriders from late 2020 to April 1, 2021
The Medium from December 10, 2020, to January 28, 2021
Harvest Moon: One World from 2020 to March 2, 2021, in North America and March 5, 2021, in Europe
The Idolmaster: Starlit Season from 2020 to 2021
Digimon Survive from 2020 to 2021 and finally into July 28, 2022, for Japan and a day later for the rest of the world.
Seven Knights: Time Wanderer from June 2020 to November 5, 2020
Monstrum physical edition from May 22, 2020 to October 23, 2020
Dragon Marked for Death version 3.0 patch for Nintendo Switch from April 21, 2020 to April 23, 2020
Everyday: Today's Menu for the Emiya Family from May 2020 to April 28, 2021
Crossfire X from 2020 to February 10, 2022
Cuphead: The Delicious Last Course DLC from 2020 to June 30, 2022
Rainbow Six Extraction from 2020 to January 20, 2022. Additionally, the original title of Rainbow Six Quarantine was renamed to avoid association with the pandemic.
Gran Turismo 7 from 2021 to March 4, 2022
Tales of Arise from 2020 to September 10, 2021
The King of Fighters XV from 2021 to February 17, 2022
God of War Ragnarök from 2021 to November 9, 2022
Ghostwire: Tokyo from Q3 2021 to March 25, 2022
Far Cry 6 from February 18 to October 7, 2021
Life Is Strange: Remastered Collection from September 10, 2021, to February 1, 2022
Battlefield 2042 from October 22 to November 19, 2021
Some games also received early releases in certain regions:
At GameStop in the United States, Doom Eternal was released a day prior to its release date to separate the crowds from those purchasing Animal Crossing: New Horizons (as both games were officially released on 20 March).
AFL Evolution 2 was released on April 16, 2020, a week prior to its original release date. To reduce physical contact, physical copies of the game were initially sold through online retailers only.
Final Fantasy VII Remake was shipped early to Europe and Australia so the players living in the "countries that are currently facing the biggest disruption" would be able to play the game on its launch day.
The second chapter of Deltarune, which was originally intended to be released as part of the full game (the release date of which has not yet been announced as of March 21, 2022), was released for free on September 17, 2021.
Some games were cancelled:
Deliver Us the Moon for Nintendo Switch, having been scheduled for a mid-2020 release.
Doom Eternal'''s invasion mode was cancelled in favor of a single-player horde mode.
Minecraft Earth, which released as early access in October 2019, closed on June 30, 2021.
Just Cause: Mobile from 2022 to 2023 before being cancelled.
Game publishers and developers have expressed concerns that further extensions of the movement control orders from the pandemic may incur additional delays. One major factor that may cause delays is the ability to capture voice acting without access to studios during physical distancing for society, even though some of members have considered working from residence remotely to avoid troubling situations. An example of this happened with the Western release of Persona 5 Strikers whose voice acting in English was meant to start in April 2020 but was delayed due to the pandemic. The actors later received audio equipment from Atlus so that they could work at home.
Services
As much of the world's population have been quarantined due to the pandemic, video game playing and other Internet use has increased significantly. Steam had over 23 million concurrent players during March 2020, surpassing all previous records while over three billion hours of content were watched on Twitch over the first quarter of 2020, a 20% increase from the previous year's. Microsoft reported a substantial increase in users of its Xbox Game Pass service in the months of March and April 2020, bringing it to over 10 million subscribers. GeForce Now capacity was temporarily exhausted in Europe before additional server capacity was added.
The additional bandwidth from video games and other Internet services created concerns that critical bandwidth would not be available for medical and other key infrastructure elements necessary to mitigate the spread of SARS-CoV-2. To help reduce demand during peak hours, the Akamai content delivery network for many video games and major digital storefronts such as Xbox Live, PlayStation Network, and Steam capped download speeds and encouraged the users to download at off-peak hours.
During quarantine and lockdown, Ubisoft announced an update for Just Dance 2020 to keep players active: customers who owned the game could access a month of the Just Dance Unlimited service. Ubisoft also announced in its official forum that the second event entitled "Power Gala", which was part of the second season "Feel the Power" in Just Dance 2020, had been postponed. The developer explained that the company wanted to protect its team due to the pandemic, and that "although [their] team still work[ed] hard to make our servers work as smoothly as possible at home", this needed to be resolved by postponing the content. Two tracks from Just Dance Unlimited were made free to make up for the delay.
Retailers
GameStop and its Canadian subsidiary, EB Games, came under criticism for its overall response to the pandemic. Notably, it received widespread criticism when, after numerous states and provinces issued "stay at home" or "shelter in place" orders requiring non-essential businesses to close up starting in March 2020, it considered its stores an essential business, stating that they provided a "significant need for technology solutions". The chain later revised this decision, closing most locations and leaving only select stores open to provide drive-up delivery of online or by-phone orders to the customers.
CeX closed all its corporate stores in the United Kingdom on 23 March and asked the franchises to do the same.
Game X Change, a regional game retailer based in Arkansas, attracted criticism for keeping the retail locations open in areas with stay at home orders.
Industry trade bodies
The Japanese game ratings body Computer Entertainment Rating Organization was forced to close operations from early April through 7 May, and upon reopening, implemented appropriate controls that reduced work hours, which is expected to delay some releases in Japan as they await a rating for retail release.
Industry support of mitigation and relief efforts
Nintendo of America donated 9,500 N95-rated face masks for first responders in the Washington state region in March after their facility was shuttered during Washington's stay-at-home program.
Twitch hosted a 12-hour charity stream on 28 March 2020, to raise money for the COVID-19 Solidarity Response Fund. The stream featured games, music and sports celebrities playing games like Fortnite and Uno.
Several game publishers worked with WHO to support its #PlayApartTogether campaign, encouraging players to continue social engagement in video games via online games instead of through physical means. Eighteen companies initially joined the effort when announced in March 2020, and at least forty more had joined by early April.
Games Done Quick, a charity-driven speedrunning event, had to move its planned June 2020 event due to the pandemic, but announced it would run a fully online "Corona Relief Done Quick" event from 17 to 19 April 2020, with money raised going to Direct Relief. The event raised over . Let's Play group The Runaway Guys added an additional through their third annual 'Colosseum' event, done in remote format (and under the title 'Colosseum Direct') due to the pandemic.
Humble Bundle offered a "Conquer COVID-19 Bundle" of games and e-books from 31 March to 7 April 2020 with all proceeds going to Direct Relief, International Rescue Committee, Doctors Without Borders, and Partners in Health. Over 200,000 bundles were sold raising over for the charities.
The Association for UK Interactive Entertainment worked with the UK's Department for Digital, Culture, Media and Sport to push the government's campaign of "Stay Home, Save Lives" into their members' video games that supported dynamic messaging like within in-game menu screens.
Former Nintendo of America president Reggie Fils-Aimé and video games journalist Harold Goldberg hosted Talking Games with Reggie and Harold, a seven-part podcast, to raise charitable funds for the New York Video Game Critics Circle to help mentor lower-income and under-served students in New York City impacted by the pandemic.
Idea Factory International held an online charity auction of an official Hyperdimension Neptunia illustration by series artist Tsunako. After the auction ended, they donated the money from the auction to help UNICEF USA's effort in fighting the virus.
Some game developers and publishers pledged to donate revenue generated by purchases to COVID-19 relief efforts:
Rockstar Games donated five percent of revenue generated by in-game purchases in Grand Theft Auto Online and Red Dead Online in April and May 2020. Its nine worldwide studios donated to local charities, including City Harvest in London and New York, the Centre for Addiction and Mental Health Foundation, Boston Museum of Science, Akshaya Patra Foundation, Connecticut Food Bank, National Black Nurses Association, and Black Girls Code.
iNK Stories donated 25 percent of the revenue from sales of the Steam version of Fire Escape.
Popular games during the pandemic
With the need to stay inside one's home to avoid infection, many gamers flocked to online games as a substitute for social interactions they would otherwise miss. Animal Crossing: New Horizons was especially popular, with people around the world turning to the game's recreation of ordinary daily life activities and social networking features as a substitute for the normalcy disrupted by the pandemic. Another very popular game during the pandemic was Grand Theft Auto Online. The game reached one of its highest simultaneous player count of 267,000 players at the beginning of 2020. Fall Guys and Among Us were particularly popular during this time, with the former being released during the pandemic and the latter receiving a surge of popularity. Some non-online games were also thematically compared to the pandemic, such as The Longing and Presentable Liberty. Microsoft Flight Simulator, first released in August 2020, has been considered popular during the pandemic, as many saw it as a safer alternative to travelling. Other games, such as The Last of Us Part II, Roblox and Project CARS 3, were also popular during the pandemic.
Notable deaths
John Horton Conway, mathematician and creator of Conway's Game of Life.
Rick May, voice actor; including the Soldier in Team Fortress 2''.
Post-COVID
Towards the end of 2023 and continuing into 2024, the video game industry saw a large number of layoffs, with over 10,000 jobs lost in 2023 and at least 8,000 in 2024 by February 2024. While other factors contributed to the layoffs, such as previous acquisitions and mergers that came after 2021, the return to normalcy after COVID changed the profitability of video games, lowering market forecasts, which the inflated industry could not sustain.
See also
2023–2024 video game industry layoffs
References
2020 in video gaming
2021 in video gaming
Health and video gaming
History of video games
Video game industry | Impact of the COVID-19 pandemic on the video game industry | [
"Technology"
] | 7,105 | [
"History of video games",
"History of computing"
] |
63,464,605 | https://en.wikipedia.org/wiki/Asus%20ZenFone%206 | The ZenFone 6 is a 2019 Android-based smartphone that was manufactured, released, and marketed by Asus. It is the only release in Asus' sixth-generation ZenFone lineup and directly succeeds the ZenFone 5Z. Asus chairman Jonney Shih unveiled the ZenFone 6 on 16 May 2019 in Valencia, Spain, and it was released in Spain the following day.
The ZenFone 6 has a larger display, a faster processor, and upgraded cameras than the ZenFone 5Z. The ZenFone 6's flip-up camera module doubles as a front-facing camera. It is the first mobile device Asus released after restructuring its smartphone division in late 2018. The ZenFone 6 was released in the Indian market as the "Asus 6Z".
Despite positive reviews, the ZenFone 6 lacked broad appeal and attracted a niche market of power users and technology enthusiasts. Supply issues resulted in delays and stock shortages, which also interfered with its success. , Asus has not released sales figures for the device, only noting the ZenFone has "created excellent sales".
History
Background
Before the ZenFone 6 was partially unveiled at the Mobile World Congress (MWC Barcelona), information about prototype devices was leaked but none of the depicted devices were marketed to the public. In October 2018, an alleged leak of a prototype smartphone with a semi-circular, off-centre cutout for the front-facing camera was circulated. In February 2019, another leaked image showed a more conventional device with thick bezels and an iridescent back. Both leaked images showed a device with conventional, vertical, triple-camera array on the rear.
In late 2018, Asus's smartphone division underwent a significant corporate restructuring process, which involved allocating (, , or as of 2018) towards a new focus on "power users and gamers." The move was prompted by the success of the gamer-focused ROG Phone and aimed to shift the division's direction towards catering to this demographic. The shift in direction was formalised in a resolution by Asus' board of directors on 13 December 2018. Asus announced then-CEO Jerry Shen's departure from Asus, effective 1 January 2019.
At the February 2019 MWC Barcelona, Asus announced that the phone would be unveiled and launched on 16 May and provided a promotional silhouette image of the phone's bezel with no cameras visible, hinting at its design. Initially, there were misunderstandings over the launch date after a two-page advertisement in the magazine Mobile World Daily with an incorrect launch date of 14 May 2019 was given to journalists.
In early May 2019, another supposedly leaked image of the ZenFone 6 appeared; it showed a device with a form factor similar to the released product, with a similarly mounted rear dual-camera module and a mechanical slider, a retractable front camera mechanism similar to the one used in the Xiaomi Mi MIX 3 in place of the flip mechanism in the final design. On 14 May 2019, two days prior to the official unveiling of the ZenFone 6, accurate renderings and specifications of the device were leaked by Taiwanese outlet Sogi.
Release
Following its unveiling on 16 May 2019, Asus gradually released the ZenFone 6 to European markets at a starting price of . On 28 May, India's Delhi High Court issued an interim order restraining Asus from selling smartphones, tablets, and accessories branded "Zen" and "ZenFone" in violation of Telecare Network India's Zen Mobile trademark. This led Asus to rebrand the phone as the "Asus 6Z" for the Indian market.
For the initial international release, the novel use of liquid metal for the camera module's casing caused inventory shortages and delays in many markets. Some model configurations were sold out on the day of release in the United States. From 22 July that year, Asus rolled out an over-the-air update to software update version .167, which caused some users' devices to crash, reboot, or get stuck in a "bootloop" where the device is stuck in a loop of turning itself on and off. An Asus representative attributed this behaviour to a hardware issue, saying the update triggers a motherboard malfunction, the only solution to which was a motherboard replacement under existing warranty.
The release of the ZenFone 6 was followed by Asus' ROG Phone II, which was announced in July 2019 and released in September 2019. The ZenFone supports Google's Android 9 Pie and Android 10, both with ZenUI 6, Asus's customised Android front end. In November 2019, Asus released an Android 10 update for the ZenFone 6, two months after Google's release of the update to Android.
In late August 2019, Asus started recruiting ZenFone 6 users for an Android 11 beta program, which was subsequently released to the public in December 2020. The flip-camera design that was introduced in the ZenFone 6 was also employed in its successors, the 2020 ZenFone 7 series and the 2021 ZenFone 8 Flip.
Edition 30
On 27 May 2019, during a special press event at Computex, Asus chairman Jonney Shih unveiled the Asus ZenFone Edition 30 to commemorate Asus' 30th anniversary. The phone features an exclusive back design, and upgraded storage and RAM to 512 GB and 12 GB respectively. The Edition 30 comes in matte black with a radial finish and has a stylised, 30th anniversary "A" with a matte black Asus logo. The device's hardware and software features are identical to those of the regular models. It is the only model to come with a 30-month warranty and production was limited to 3,000 units.
Features
Design
The ZenFone 6 is available in glossy Midnight Black and glossy Twilight Silver, silver-blue shade.
Its unique flip-camera module is similar to that of the Samsung Galaxy A80, which has a combined sliding-rotating main camera. The camera's flip mechanism is driven by a miniature stepper motor and a magnetically linked reduction gearbox, resulting in two-degree microsteps. The gearbox prevents direct, external actuation of the stepper motor, reducing the risk of damage to the stepper motor and the internal mechanisms. The camera module's casing is constructed of an amorphous, metallic alloy that is similar to Liquidmetal in its durability, weight, high yield strength, and anti-wearing properties needed in a mechanical component that is subject to repeated stress.
The IPS LCD display is marketed as a "NanoEdge display" for the reduced bezel size. The display's Corning Gorilla Glass 6 is curved using Nano Molding Technology. The back panel is formed from Gorilla Glass 3 and has a capacitive fingerprint sensor.
On one edge, the ZenFone 6 has a function-customisable "Smart Key" with tactile indents, a volume rocker, and a power button that are outlined in blue on the black models. The ZenFone 6 has received the Japan Institute of Design Promotion's Good Design Award in 2019 and a iF Product Design Award in 2020.
Hardware
The ZenFone 6 has a Qualcomm Snapdragon 855 system on a chip running at stock clock speed and memory capacities of 6 GB of LPDDR4X RAM and 64 GB of UFS 2.1 storage, and up to 12 GB and 512 GB respectively for the 30th Anniversary Edition.
The device uses a double-layer, stacked motherboard design that was used in Apple's 2017 iPhone X and successive iPhone models. The motherboard's printed circuit board has Anylayer interconnect technology, resulting in a smaller size, which Asus says enabled them to fit a large 5,000 mAh battery into the chassis.
Software
The ZenFone 6 debuted alongside ZenUI 6, a new version of Asus' customisation of the Android operating system that was initially based on Android 9. The ZenFone 6 has software features that are specific to the flip camera, including an object-tracking video mode, an auto-panorama mode, and manual camera-angle controls. Changes to ZenUI 6 include a greater focus on single-handed operation, an overhauled notifications menu, dark mode with a light-on-dark color scheme, and a reduced number of preinstalled applications. Android 10 was released for the device in November 2019, and Android 11 was released in December 2020. The last software and security update for the ZenFone 6 was released in August 2021.
Reception
The ZenFone 6 received positive reviews from media outlets and was praised for its value proposition, long battery life, clean implementation of Android, edge-to-edge display, and general build quality for its price. Asus said the device "has been well evaluated and created excellent sales". The ZenFone 6 was praised by reviewers as one of the few 2019 flagship devices that retained the headphone jack.
Concerns over the long-term durability of the device's flip camera, especially its novel design, were raised. Asus rates the mechanism to withstand up to 100,000 actuations. Reviewers praised the versatility of the flip-camera concept but some considered it to be a gimmick. The flip camera enabled the ZenFone 6 to be one of the best selfie cameras of 2019 with a DxOMark selfie score of 98, the highest-yet at the time of review. The phone received a DxOMark camera score—a quantitative measure of camera quality—of 104, the highest for an Asus device.
Business Insider dubbed the device "the best new smartphone of 2019 so far", Android Authority called it "[a]n absolute steal", while The Verge praised its "incredible battery life". In terms of software, reviewers noted ZenUI 6 provides an experience closer to that of stock Android—the version of the Android mobile operating system developed and designed by Google. Reviewers also praised the relatively frequent software updates, however, were also disappointed by the lack of support for Android 12 with software and security updates ceasing in 2021. In February 2020, eight months after the phone's release, online publication Digital Trends affirmed their recommendation of the ZenFone 6 as "one of [their] top smartphone recommendations" for the price of , taking into account devices that had been released in the interim.
Critics noted the phone lacks several features that are present on other high-end devices; these include an OLED display, optical image stabilisation, high-speed charging, wireless charging, and water resistance. Reports also noted the lack of advertising and mainstream appeal in western markets. , the ZenFone 6 had sold over 100,000 units in Taiwan, its native market.
References
External links
Mobile phones introduced in 2019
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording
Discontinued flagship smartphones
Asus ZenFone | Asus ZenFone 6 | [
"Technology"
] | 2,265 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
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63,464,654 | https://en.wikipedia.org/wiki/Smacoviridae | Smacoviridae is a family of single-stranded DNA viruses. The genomes of this family are small (2.3–2.8 kilobases in length). The name Smacoviridae stands for 'small circular genome virus'. The genomes are circular single-stranded DNA and encode rolling-circle replication initiation proteins (Rep) and unique capsid proteins. As of 2021, 12 genera and 84 species are recognized in this family. The viruses in this taxon were isolated from faecal samples from insects and vertebrates by metagenomic methods. Little is known about their biology.
Taxonomy
The family Smacoviridae is the sole member of the order Cremevirales and together with other families of CRESS DNA viruses is included within the phylum Cressdnaviricota.
The family currently includes the following genera:
Babosmacovirus
Bonzesmacovirus
Bostasmacovirus
Bovismacovirus
Cosmacovirus
Dragsmacovirus
Drosmacovirus
Felismacovirus
Huchismacovirus
Inpeasmacovirus
Porprismacovirus
Simismacovirus
Biology
These viruses have single stranded genomes of 2.3–2.8 kilobases in length. The genome encodes two proteins, a Rep (replicator) and a CP (capsid) protein.
References
DNA viruses
Virus families | Smacoviridae | [
"Biology"
] | 284 | [
"Viruses",
"DNA viruses"
] |
63,465,088 | https://en.wikipedia.org/wiki/NGC%20996 | NGC 996 is an elliptical galaxy of the Hubble type E0 in the constellation Andromeda. It is estimated to be 210 million light years from the Milky Way and has a diameter of approximately 75,000 ly. It was discovered on December 7, 1871 by astronomer Édouard Stephan.
Supernova
One supernova has been observed in NGC 996: SN 1996bq (type unknown, mag. 18.7) was discovered by Christian Pollas on 12 October 1996.
See also
List of NGC objects (1–1000)
References
Elliptical galaxies
Andromeda (constellation)
0996
02123
010015
Astronomical objects discovered in 1871
Discoveries by Édouard Stephan | NGC 996 | [
"Astronomy"
] | 138 | [
"Andromeda (constellation)",
"Constellations"
] |
63,465,115 | https://en.wikipedia.org/wiki/NGC%20998 | NGC 998 is a spiral galaxy in the constellation Cetus. It is estimated to be 294 million light years from the Milky Way and has a diameter of approximately 90,000 ly. Together with NGC 997, it forms a gravitationally bound pair of galaxies. NGC 998 was discovered by astronomer Albert Marth on 10 November 1863 using a 48-inch telescope.
See also
List of NGC objects (1–1000)
References
External links
Cetus
0998
Spiral galaxies
009934 | NGC 998 | [
"Astronomy"
] | 102 | [
"Cetus",
"Constellations"
] |
63,465,176 | https://en.wikipedia.org/wiki/NGC%20991 | NGC 991 is an intermediate spiral galaxy the constellation Cetus. This galaxy was discovered by astronomer William Herschel in 1785.
One supernova has been observed in NGC 991: SN 1984L (typeIb, mag. 14) was discovered by Robert Evans on 28 August 1984.
See also
List of NGC objects (1–1000)
References
External links
Intermediate spiral galaxies
Cetus
0991
009846 | NGC 991 | [
"Astronomy"
] | 86 | [
"Cetus",
"Constellations"
] |
63,465,236 | https://en.wikipedia.org/wiki/Shvab%E2%80%93Zeldovich%20formulation | The Shvab–Zeldovich formulation is an approach to remove the chemical-source terms from the conservation equations for energy and chemical species by linear combinations of independent variables, when the conservation equations are expressed in a common form. Expressing conservation equations in common form often limits the range of applicability of the formulation. The method was first introduced by V. A. Shvab in 1948 and by Yakov Zeldovich in 1949.
Method
For simplicity, assume combustion takes place in a single global irreversible reaction
where is the ith chemical species of the total species and and are the stoichiometric coefficients of the reactants and products, respectively. Then, it can be shown from the law of mass action that the rate of moles produced per unit volume of any species is constant and given by
where is the mass of species i produced or consumed per unit volume and is the molecular weight of species i.
The main approximation involved in Shvab–Zeldovich formulation is that all binary diffusion coefficients of all pairs of species are the same and equal to the thermal diffusivity. In other words, Lewis number of all species are constant and equal to one. This puts a limitation on the range of applicability of the formulation since in reality, except for methane, ethylene, oxygen and some other reactants, Lewis numbers vary significantly from unity. The steady, low Mach number conservation equations for the species and energy in terms of the rescaled independent variables
where is the mass fraction of species i, is the specific heat at constant pressure of the mixture, is the temperature and is the formation enthalpy of species i, reduce to
where is the gas density and is the flow velocity. The above set of nonlinear equations, expressed in a common form, can be replaced with linear equations and one nonlinear equation. Suppose the nonlinear equation corresponds to so that
then by defining the linear combinations and with , the remaining governing equations required become
The linear combinations automatically removes the nonlinear reaction term in the above equations.
Shvab–Zeldovich–Liñán formulation
Shvab–Zeldovich–Liñán formulation was introduced by Amable Liñán in 1991 for diffusion-flame problems where the chemical time scale is infinitely small (Burke–Schumann limit) so that the flame appears as a thin reaction sheet. The reactants can have Lewis number that is not necessarily equal to one.
Suppose the non-dimensional scalar equations for fuel mass fraction (defined such that it takes a unit value in the fuel stream), oxidizer mass fraction (defined such that it takes a unit value in the oxidizer stream) and non-dimensional temperature (measured in units of oxidizer-stream temperature) are given by
where is the reaction rate, is the appropriate Damköhler number, is the mass of oxidizer stream required to burn unit mass of fuel stream, is the non-dimensional amount of heat released per unit mass of fuel stream burnt and is the Arrhenius exponent. Here, and are the Lewis number of the fuel and oxygen, respectively and is the thermal diffusivity. In the Burke–Schumann limit, leading to the equilibrium condition
.
In this case, the reaction terms on the right-hand side become Dirac delta functions. To solve this problem, Liñán introduced the following functions
where , is the fuel-stream temperature and is the adiabatic flame temperature, both measured in units of oxidizer-stream temperature. Introducing these functions reduces the governing equations to
where is the mean (or, effective) Lewis number. The relationship between and and between and can be derived from the equilibrium condition.
At the stoichiometric surface (the flame surface), both and are equal to zero, leading to , , and , where is the flame temperature (measured in units of oxidizer-stream temperature) that is, in general, not equal to unless . On the fuel stream, since , we have . Similarly, on the oxidizer stream, since , we have .
The equilibrium condition defines
The above relations define the piecewise function
where is a mean Lewis number. This leads to a nonlinear equation for . Since is only a function of and , the above expressions can be used to define the function
With appropriate boundary conditions for , the problem can be solved.
It can be shown that and are conserved scalars, that is, their derivatives are continuous when crossing the reaction sheet, whereas and have gradient jumps across the flame sheet.
References
Combustion
Fluid dynamics | Shvab–Zeldovich formulation | [
"Chemistry",
"Engineering"
] | 916 | [
"Piping",
"Chemical engineering",
"Combustion",
"Fluid dynamics"
] |
63,465,390 | https://en.wikipedia.org/wiki/Marine%20viruses | Marine viruses are defined by their habitat as viruses that are found in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. Viruses are small infectious agents that can only replicate inside the living cells of a host organism, because they need the replication machinery of the host to do so. They can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea.
When not inside a cell or in the process of infecting a cell, viruses exist in the form of independent particles called virions. A virion contains a genome (a long molecule that carries genetic information in the form of either DNA or RNA) surrounded by a capsid (a protein coat protecting the genetic material). The shapes of these virus particles range from simple helical and icosahedral forms for some virus species to more complex structures for others. Most virus species have virions that are too small to be seen with an optical microscope. The average virion is about one one-hundredth the linear size of the average bacterium.
A teaspoon of seawater typically contains about fifty million viruses. Most of these viruses are bacteriophages which infect and destroy marine bacteria and control the growth of phytoplankton at the base of the marine food web. Bacteriophages are harmless to plants and animals but are essential to the regulation of marine ecosystems. They supply key mechanisms for recycling ocean carbon and nutrients. In a process known as the viral shunt, organic molecules released from dead bacterial cells stimulate fresh bacterial and algal growth. In particular, the breaking down of bacteria by viruses (lysis) has been shown to enhance nitrogen cycling and stimulate phytoplankton growth. Viral activity also affects the biological pump, the process which sequesters carbon in the deep ocean. By increasing the amount of respiration in the oceans, viruses are indirectly responsible for reducing the amount of carbon dioxide in the atmosphere by approximately 3 gigatonnes of carbon per year.
Marine microorganisms make up about 70% of the total marine biomass. It is estimated marine viruses kill 20% of the microorganism biomass every day. Viruses are the main agents responsible for the rapid destruction of harmful algal blooms which often kill other marine life. The number of viruses in the oceans decreases further offshore and deeper into the water, where there are fewer host organisms. Viruses are an important natural means of transferring genes between different species, which increases genetic diversity and drives evolution. It is thought viruses played a central role in early evolution before the diversification of bacteria, archaea and eukaryotes, at the time of the last universal common ancestor of life on Earth. Viruses are still one of the largest areas of unexplored genetic diversity on Earth.
Background
Viruses are now recognised as ancient and as having origins that pre-date the divergence of life into the three domains. They are found wherever there is life and have probably existed since living cells first evolved. The origins of viruses in the evolutionary history of life are unclear because they do not form fossils. Molecular techniques are used to compare the DNA or RNA of viruses and are a useful means of investigating how they arose. Some viruses may have evolved from plasmids—pieces of DNA that can move between cells—while others may have evolved from bacteria. In evolution, viruses are an important means of horizontal gene transfer, which increases genetic diversity.
Opinions differ on whether viruses are a form of life or organic structures that interact with living organisms. They are considered by some to be a life form, because they carry genetic material, reproduce by creating multiple copies of themselves through self-assembly, and evolve through natural selection. However they lack key characteristics such as a cellular structure generally considered necessary to count as life. Because they possess some but not all such qualities, viruses have been described as replicators and as "organisms at the edge of life".
The existence of viruses in the ocean was discovered through electron microscopy and epifluorescence microscopy of ecological water samples, and later through metagenomic sampling of uncultured viral samples. Marine viruses, although microscopic and essentially unnoticed by scientists until recently, are the most abundant and diverse biological entities in the ocean. Viruses have an estimated abundance of 1030 in the ocean, or between 106 and 1011 viruses per millilitre. Quantification of marine viruses was originally performed using transmission electron microscopy but has been replaced by epifluorescence or flow cytometry.
Bacteriophages
Bacteriophages, often contracted to phages, are viruses that parasitize bacteria for replication. As aptly named, marine phages parasitize marine bacteria, such as cyanobacteria. They are a diverse group of viruses which are the most abundant biological entity in marine environments, because their hosts, bacteria, are typically the numerically dominant cellular life in the sea. There are up to ten times more phages in the oceans than there are bacteria, reaching levels of 250 million bacteriophages per millilitre of seawater. These viruses infect specific bacteria by binding to surface receptor molecules and then entering the cell. Within a short amount of time, in some cases just minutes, bacterial polymerase starts translating viral mRNA into protein. These proteins go on to become either new virions within the cell, helper proteins, which help assembly of new virions, or proteins involved in cell lysis. Viral enzymes aid in the breakdown of the cell membrane, and there are phages that can replicate three hundred phages twenty minutes after injection.
Bacteria defend themselves from bacteriophages by producing enzymes that destroy foreign DNA. These enzymes, called restriction endonucleases, cut up the viral DNA that bacteriophages inject into bacterial cells. Bacteria also contain a system that uses CRISPR sequences to retain fragments of the genomes of viruses that the bacteria have come into contact with in the past, which allows them to block the virus's replication through a form of RNA interference. This genetic system provides bacteria with acquired immunity to infection.
Microbes drive the nutrient transformations that sustain Earth's ecosystems, and the viruses that infect these microbes modulate both microbial population size and diversity. The cyanobacterium Prochlorococcus, the most abundant oxygenic phototroph on Earth, contributes a substantial fraction of global primary carbon production, and often reaches densities of over 100,000 cells per milliliter in oligotrophic and temperate oceans. Hence, viral (cyanophage) infection and lysis of Prochlorococcus represent an important component of the global carbon cycle. In addition to their ecological role in inducing host mortality, cyanophages influence the metabolism and evolution of their hosts by co-opting and exchanging genes, including core photosynthesis genes.
For a long time, tailed phages of the order Caudovirales seemed to dominate marine ecosystems in number and diversity of organisms. However, as a result of more recent research, non-tailed viruses appear to dominate multiple depths and oceanic regions. These non-tailed phages also infect marine bacteria, and include the families Corticoviridae,
Inoviridae,
Microviridae and Autolykiviridae.
As of September 2023, Halomonas phage vB HmeY H4907 is the first virus isolated from the deepest part of the ocean.
Archaeal viruses
Archaean viruses replicate within archaea: these are double-stranded DNA viruses with unusual and sometimes unique shapes. These viruses have been studied in most detail in the thermophilic archaea, particularly the orders Sulfolobales and Thermoproteales. Defences against these viruses involve RNA interference from repetitive DNA sequences within archaean genomes that are related to the genes of the viruses. Most archaea have CRISPR–Cas systems as an adaptive defence against viruses. These enable archaea to retain sections of viral DNA, which are then used to target and eliminate subsequent infections by the virus using a process similar to RNA interference.
Fungal viruses
Mycoviruses, also known as mycophages, are viruses that infect fungi. The infection of fungal cells is different from that of animal cells. Fungi have a rigid cell wall made of chitin, so most viruses can get inside these cells only after trauma to the cell wall.
Eukaryote viruses
Marine protists
By 2015, about 40 viruses affecting marine protists had been isolated and examined, most of them viruses of microalgae. The genomes of these marine protist viruses are highly diverse. Marine algae can be infected by viruses in the family Phycodnaviridae. These are large (100–560 kb) double-stranded DNA viruses with icosahedral shaped capsids. By 2014, 33 species divided into six genera had been identified within the family, which belongs to a super-group of large viruses known as nucleocytoplasmic large DNA viruses. Evidence was published in 2014 suggesting some strains of Phycodnaviridae might infect humans rather than just algal species, as was previously believed. Most genera under this family enter the host cell by cell receptor endocytosis and replicate in the nucleus.
Phycodnaviridae play important ecological roles by regulating the growth and productivity of their algal hosts. Algal species such Heterosigma akashiwo and the genus Chrysochromulina can form dense blooms which can be damaging to fisheries, resulting in losses in the aquaculture industry. Heterosigma akashiwo virus (HaV) has been suggested for use as a microbial agent to prevent the recurrence of toxic red tides produced by this algal species. The coccolithovirus Emiliania huxleyi virus 86, a giant double-stranded DNA virus, infects the ubiquitous coccolithophore Emiliania huxleyi. This virus has one of the largest known genomes among marine viruses. Phycodnaviridae cause death and lysis of freshwater and marine algal species, liberating organic carbon, nitrogen and phosphorus into the water, providing nutrients for the microbial loop.
The virus-to-prokaryote ratio, VPR, is often used as an indicator of the relationship between viruses and hosts. Studies have used VPR to indirectly infer virus impact on marine microbial productivity, mortality, and biogeochemical cycling. However, in making these approximations, scientists assume a VPR of 10:1, the median observed VPR in the surface ocean. The actual VPR varies greatly depending on location, so VPR may not be the accurate proxy for viral activity or abundance as it has been treated.
Marine invertebrates
Marine invertebrates are susceptible to viral diseases. Sea star wasting disease is a disease of starfish and several other echinoderms that appears sporadically, causing mass mortality of those affected. There are around 40 different species of sea stars that have been affected by this disease. In 2014 it was suggested that the disease is associated with a single-stranded DNA virus now known as the sea star-associated densovirus (SSaDV); however, sea star wasting disease is not fully understood.
Marine vertebrates
Fish are particularly prone to infections with rhabdoviruses, which are distinct from, but related to rabies virus. At least nine types of rhabdovirus cause economically important diseases in species including salmon, pike, perch, sea bass, carp and cod. The symptoms include anaemia, bleeding, lethargy and a mortality rate that is affected by the temperature of the water. In hatcheries the diseases are often controlled by increasing the temperature to . Like all vertebrates, fish suffer from herpes viruses. These ancient viruses have co-evolved with their hosts and are highly species-specific. In fish, they cause cancerous tumours and non-cancerous growths called hyperplasia.
In 1984, infectious salmon anemia (ISAv) was discovered in Norway in an Atlantic salmon hatchery. Eighty per cent of the fish in the outbreak died. ISAv, a viral disease, is now a major threat to the viability of Atlantic salmon farming. As the name implies, it causes severe anemia of infected fish. Unlike mammals, the red blood cells of fish have DNA and can become infected with viruses. Management strategies include developing a vaccine and improving genetic resistance to the disease.
Marine mammals are also susceptible to marine viral infections. In 1988 and 2002, thousands of harbour seals were killed in Europe by phocine distemper virus. Many other viruses, including caliciviruses, herpesviruses, adenoviruses and parvoviruses, circulate in marine mammal populations.
Giant marine viruses
Most viruses range in length from about 20 to 300 nanometers. This can be contrasted with the length of bacteria, which starts at about 400 nanometers. There are also giant viruses, often called giruses, typically about 1000 nanometers (one micron) in length.
All giant viruses belong to the phylum Nucleocytoviricota (NCLDV), together with poxviruses.
The largest known of these is Tupanvirus. This genus of giant virus was discovered in 2018 in the deep ocean as well as a soda lake, and can reach up to 2.3 microns in total length.
The discovery and subsequent characterization of giant viruses has triggered some debate concerning their evolutionary origins. The two main hypotheses for their origin are that either they evolved from small viruses, picking up DNA from host organisms, or that they evolved from very complicated organisms into the current form which is not self-sufficient for reproduction. What sort of complicated organism giant viruses might have diverged from is also a topic of debate. One proposal is that the origin point actually represents a fourth domain of life, but this has been largely discounted.
Virophages
Virophages are small, double-stranded DNA viruses that rely on the co-infection of giant viruses. Virophages rely on the viral replication factory of the co-infecting giant virus for their own replication. One of the characteristics of virophages is that they have a parasitic relationship with the co-infecting virus. Their dependence upon the giant virus for replication often results in the deactivation of the giant viruses. The virophage may improve the recovery and survival of the host organism. Unlike other satellite viruses, virophages have a parasitic effect on their co-infecting virus. Virophages have been observed to render a giant virus inactive and thereby improve the condition of the host organism.
All known virophages are grouped into the family Lavidaviridae (from "large virus dependent or associated" + -viridae). The first virophage was discovered in a cooling tower in Paris in 2008. It was discovered with its co-infecting giant virus, Acanthamoeba castellanii mamavirus (ACMV). The virophage was named Sputnik and its replication relied entirely on the co-infection of ACMV and its cytoplasmic replication machinery. Sputnik was also discovered to have an inhibitory effect on ACMV and improved the survival of the host. Other characterised virophages include Sputnik 2, Sputnik 3, Zamilon and Mavirus.
Most of these virophages were discovered by analyzing metagenomic data sets. In metagenomic analysis, DNA sequences are run through multiple bioinformatic algorithms which pull out certain important patterns and characteristics. In these data sets are giant viruses and virophages. They are separated by looking for sequences around 17 to 20 kbp long which have similarities to already sequenced virophages. These virophages can have linear or circular double-stranded DNA genomes. Virophages in culture have icosahedral capsid particles that measure around 40 to 80 nanometers long. Virophage particles are so small that electron microscopy must be used to view these particles. Metagenomic sequence-based analyses have been used to predict around 57 complete and partial virophage genomes and in December 2019 to identify 328 high-quality (complete or near-complete) genomes from diverse habitats including the human gut, plant rhizosphere, and terrestrial subsurface, from 27 distinct taxonomic clades.
A giant marine virus CroV infects and causes the death by lysis of the marine zooflagellate Cafeteria roenbergensis. This impacts coastal ecology because Cafeteria roenbergensis feeds on bacteria found in the water. When there are low numbers of Cafeteria roenbergensis due to extensive CroV infections, the bacterial populations rise exponentially. The impact of CroV on natural populations of C. roenbergensis remains unknown; however, the virus has been found to be very host specific, and does not infect other closely related organisms. Cafeteria roenbergensis is also infected by a second virus, the Mavirus virophage, during co-infection with CroV. This virus interferes with the replication of CroV, which leads to the survival of C. roenbergensis cells. Mavirus is able to integrate into the genome of cells of C. roenbergensis and thereby confer immunity to the population.
Role of marine viruses
Although marine viruses have only recently been studied extensively, they are already known to hold critical roles in many ecosystem functions and cycles. Marine viruses offer a number of important ecosystem services and are essential to the regulation of marine ecosystems. Marine bacteriophages and other viruses appear to influence biogeochemical cycles globally, provide and regulate microbial biodiversity, cycle carbon through marine food webs, and are essential in preventing bacterial population explosions.
Viral shunt
The dominant hosts for viruses in the ocean are marine microorganisms, such as bacteria. Bacteriophages are harmless to plants and animals, and are essential to the regulation of marine and freshwater ecosystems are important mortality agents of phytoplankton, the base of the foodchain in aquatic environments. They infect and destroy bacteria in aquatic microbial communities, and are one of the most important mechanisms of recycling carbon and nutrient cycling in marine environments. The organic molecules released from the dead bacterial cells stimulate fresh bacterial and algal growth, in a process known as the viral shunt.
In this way, marine viruses are thought to play an important role in nutrient cycles by increasing the efficiency of the biological pump. Viruses cause lysis of living cells, that is, they break the cell membranes down. This releases compounds such as amino acids and nucleic acids, which tend to be recycled near the surface.
Viral activity also enhances the ability of the biological pump to sequester carbon in the deep ocean. Lysis releases more indigestible carbon-rich material like that found in cell walls, which is likely exported to deeper waters. Thus, the material that is exported to deeper waters by the viral shunt is probably more carbon rich than the material from which it was derived. By increasing the amount of respiration in the oceans, viruses are indirectly responsible for reducing the amount of carbon dioxide in the atmosphere by about three gigatonnes of carbon per year. Lysis of bacteria by viruses has been shown to also enhance nitrogen cycling and stimulate phytoplankton growth.
The viral shunt pathway is a mechanism that prevents (prokaryotic and eukaryotic) marine microbial particulate organic matter (POM) from migrating up trophic levels by recycling them into dissolved organic matter (DOM), which can be readily taken up by microorganisms. Viral shunting helps maintain diversity within the microbial ecosystem by preventing a single species of marine microbe from dominating the micro-environment. The DOM recycled by the viral shunt pathway is comparable to the amount generated by the other main sources of marine DOM.
Viruses are the most abundant biological entity in marine environments. On average there are about ten million of them in one milliliter of seawater. Most of these viruses are bacteriophages infecting heterotrophic bacteria and cyanophages infecting cyanobacteria. Viruses easily infect microorganisms in the microbial loop due to their relative abundance compared to microbes. Prokaryotic and eukaryotic mortality contribute to carbon nutrient recycling through cell lysis. There is evidence as well of nitrogen (specifically ammonium) regeneration. This nutrient recycling helps stimulates microbial growth. As much as 25% of the primary production from phytoplankton in the global oceans may be recycled within the microbial loop through viral shunting.
Regulating the carbon cycle
Viruses act as "regulators" of the global carbon cycle because they impact the material cycles and energy flows of food webs and the microbial loop. The average contribution of viruses to the Earth ecosystem carbon cycle is 8.6%, of which its contribution to marine ecosystems (1.4%) is less than its contribution to terrestrial (6.7%) and freshwater (17.8%) ecosystems. Over the past 2,000 years, anthropogenic activities and climate change have gradually altered the regulatory role of viruses in ecosystem carbon cycling processes. This has been particularly conspicuous over the past 200 years due to rapid industrialization and the attendant population growth.
Limiting algal blooms
Microorganisms make up about 70% of the marine biomass. It is estimated viruses kill 20% of the microorganism biomass each day and that there are 15 times as many viruses in the oceans as there are bacteria and archaea. Viruses are the main agents responsible for the rapid destruction of harmful algal blooms, which often kill other marine life. Scientists are exploring the potential of marine cyanophages to be used to prevent or reverse eutrophication. The number of viruses in the oceans decreases further offshore and deeper into the water, where there are fewer host organisms.
Gene transfer
Marine bacteriophages often contain auxiliary metabolic genes, host-derived genes thought to sustain viral replication by supplementing host metabolism during viral infection. These genes can impact multiple biogeochemical cycles, including carbon, phosphorus, sulfur, and nitrogen.
Viruses are an important natural means of transferring genes between different species, which increases genetic diversity and drives evolution. It is thought viruses played a central role in early evolution, before bacteria, archaea and eukaryotes diversified, at the time of the last universal common ancestor of life on Earth. Viruses are still one of the largest reservoirs of unexplored genetic diversity on Earth.
Marine habitats
Along the coast
Marine coastal habitats sit at the interface between the land and the ocean. It is likely that RNA viruses play significant roles in these environments.
At the ocean surface
Marine surface habitats sit at the interface between the atmosphere and the ocean. The biofilm-like habitat at the surface of the ocean harbours surface-dwelling microorganisms, commonly referred to as neuston. Viruses in the microlayer, the so-called virioneuston, have recently become of interest to researchers as enigmatic biological entities in the boundary surface layers with potentially important ecological impacts. Given this vast air–water interface sits at the intersection of major air–water exchange processes spanning more than 70% of the global surface area, it is likely to have profound implications for marine biogeochemical cycles, on the microbial loop and gas exchange, as well as the marine food web structure, the global dispersal of airborne viruses originating from the sea surface microlayer, and human health.
In the water column
Marine viral activity presents a potential explanation of the paradox of the plankton proposed by George Hutchinson in 1961. The paradox of the plankton is that many plankton species have been identified in small regions in the ocean where limited resources should create competitive exclusion, limiting the number of coexisting species. Marine viruses could play a role in this effect, as viral infection increases as potential contact with hosts increases. Viruses could therefore control the populations of plankton species that grow too abundant, allowing a wide diversity of species to coexist.
In sediments
Marine bacteriophages play an important role in deep sea ecosystems. There are between 5x1012 and 1x1013 phages per square metre in deep sea sediments and their abundance closely correlates with the number of prokaryotes found in the sediments. They are responsible for the death of 80% of the prokaryotes found in the sediments, and almost all of these deaths are caused by cell lysis (bursting). This allows nitrogen, carbon, and phosphorus from the living cells to be converted into dissolved organic matter and detritus, contributing to the high rate of nutrient turnover in deep sea sediments. Because of the importance of deep sea sediments in biogeochemical cycles, marine bacteriophages influence the carbon, nitrogen and phosphorus cycles. More research needs to be done to more precisely elucidate these influences.
In hydrothermal vents
Viruses are part of the hydrothermal vent microbial community and their influence on the microbial ecology in these ecosystems is a burgeoning field of research. Viruses are the most abundant life in the ocean, harboring the greatest reservoir of genetic diversity. As their infections are often fatal, they constitute a significant source of mortality and thus have widespread influence on biological oceanographic processes, evolution and biogeochemical cycling within the ocean. Evidence has been found however to indicate that viruses found in vent habitats have adopted a more mutualistic than parasitic evolutionary strategy in order to survive the extreme and volatile environment they exist in. Deep-sea hydrothermal vents were found to have high numbers of viruses indicating high viral production. Like in other marine environments, deep-sea hydrothermal viruses affect abundance and diversity of prokaryotes and therefore impact microbial biogeochemical cycling by lysing their hosts to replicate. However, in contrast to their role as a source of mortality and population control, viruses have also been postulated to enhance survival of prokaryotes in extreme environments, acting as reservoirs of genetic information. The interactions of the virosphere with microorganisms under environmental stresses is therefore thought to aide microorganism survival through dispersal of host genes through horizontal gene transfer.
Polar regions
In addition to varied topographies and in spite of an extremely cold climate, the polar aquatic regions are teeming with microbial life. Even in sub-glacial regions, cellular life has adapted to these extreme environments where perhaps there are traces of early microbes on Earth. As grazing by macrofauna is limited in most of these polar regions, viruses are being recognised for their role as important agents of mortality, thereby influencing the biogeochemical cycling of nutrients that, in turn, impact community dynamics at seasonal and spatial scales. The polar regions are characterised by truncated food webs, and the role of viruses in ecosystem function is likely to be even greater than elsewhere in the marine food web, yet their diversity is still relatively under-explored, and the way in which they affect polar communities is not well understood, particularly in nutrient cycling.
Distribution
Viruses are highly host specific. A marine virus is more likely to infect cooccurring organisms, those that live in the same region the virus lives in. Therefore, biogeography is an important factor in a virion's ability to infect.
Knowledge of this variation in viral populations across spatiotemporal and other environmental gradients is supported by viral morphology, as determined by transmission electron microscopy (TEM). Non-tailed viruses appear to be dominant in multiple depths and oceanic regions, followed by the Caudovirales myoviruses, podoviruses, and siphoviruses. However, viruses belonging to families Corticoviridae, Inoviridae and Microviridae are also known to infect diverse marine bacteria. Metagenomic evidence suggests that microviruses (icosahedral ssDNA phages) are particularly prevalent in marine habitats.
Metagenomic approaches to assess viral diversity are often limited by a lack of reference sequences, leaving many sequences unannotated. However, viral contigs are generated through direct sequencing of a viral fraction, typically generated after 0.02-um filtration of a marine water sample, or through bioinformatics approaches to identify viral contigs or viral genomes from a microbial metagenome. Novel tools to identify putative viral contigs, such as VirSorter and VirFinder, allow for the assessment of patterns of viral abundance, host range, and functional content of marine bacteriophage.
See also
Human viruses in water
Varidnaviria
References
Viruses
Marine organisms
Planktology
Biological oceanography
Marine biology | Marine viruses | [
"Biology"
] | 5,936 | [
"Viruses",
"Tree of life (biology)",
"Microorganisms",
"Marine biology"
] |
63,465,767 | https://en.wikipedia.org/wiki/NGC%20992 | NGC 992 is a spiral galaxy in the Aries constellation and is estimated to be 188 million light years from the Milky Way. NGC 992 was discovered by astronomers Lewis A. Swift on September 6, 1886.
See also
List of NGC objects (1–1000)
References
External links
Spiral galaxies
0992
Aries (constellation)
009938 | NGC 992 | [
"Astronomy"
] | 73 | [
"Aries (constellation)",
"Constellations"
] |
63,466,062 | https://en.wikipedia.org/wiki/601st%20Engineer%20Grouping%20%28Argentina%29 | The 601 Engineer Grouping (Agr Ing 601) is an Argentine Army (EA) combat engineer grouping that specialised CBRN defense management, defusing and disposal of bombs and land mines, disaster response, hydraulic engineering, hyperbaric welding, military engineering, and wildfire prevention. It is based at Campo de Mayo Army Garrison.
Structure
601 Engineer Grouping Headquarters. Campo de Mayo Army Garrison.
601 Engineer Battalion. Campo de Mayo Army Garrison.
601 CBRN and Emergency Support Company. San Nicolás de los Arroyos Barracks.
601 Facilities Maintenance Engineer Company. Villa Martelli Army Garrison.
601 Army Divers Engineer Company. Villa Martelli Army Garrison.
601 Transport Engineer Company. Campo de Mayo Army Garrison.
601 Water Engineer Company. Campo de Mayo Army Garrison.
Source
Humanitarian aids
In 2019, the Ministry of Defense supplied the 601 Engineer Grouping with heavy equipment, water treatment plants, pneumatic machines and tools, New Holland D-180C bulldozers, Komatsu WA-320 front loaders, Case 580-W backhoe loaders, GEFCO drills and Sany STC-800 cranes. Argentine Army's Engineer Branch personnel manufactured a water purification and bagging plant. It has a capacity of 6000 L by micro filtration or 3000 by reverse osmosis, and can pack 1200 sachets of water per hour.
In 2019, 601 Engineer Grouping elements deployed at Santa Cruz de la Sierra y Concepción, Bolivia, in order to provide logistical support to the fight against Amazon rainforest wildfires. The movement was carried out in coordination with units of the Navy of the Argentine Republic. Personnel and equipment of the Grouping with its Headquarters and Staff joined the mission, in addition to the 601st Water Engineer Company. Also operators of road machinery of the 601st Engineer Battalion. An approximate number of 200 troops was totaled.
References
Army units and formations of Argentina
San Miguel Partido
Engineering units and formations
Group sized units of armies (land forces) | 601st Engineer Grouping (Argentina) | [
"Engineering"
] | 406 | [
"Engineering units and formations",
"Military engineering"
] |
63,467,615 | https://en.wikipedia.org/wiki/Iron%28tetraphenylporphyrinato%29%20chloride | Iron(tetraporphyrinato) chloride is the coordination complex with the formula Fe(TPP)Cl where TPP is the dianion [C44H28N4]2-. The compound forms blue microcrystals that dissolve in chlorinated solvent to give brown solutions. In terms of structure, the complex is five-coordinate with idealized C4v point group symmetry. It is one of more common transition metal porphyrin complexes.
Synthesis and reactions
Fe(TPP)Cl is prepared by the reaction of tetraphenylporphyrin (H2TPP) and ferrous chloride in the presence of air:
H2TPP + FeCl2 + 1/4 O2 → Fe(TPP)Cl + HCl + 1/2 H2O
The chloride can be replaced with other halides and pseudohalides. Base gives the "mu-oxo dimer":
2 Fe(TPP)Cl + 2 NaOH → [Fe(TPP)]2O + 2 NaCl + H2O
Most relevant to catalysis, the complex is easily reduced to give ferrous derivatives (L = pyridine, imidazole):
Fe(TPP)Cl + e- + 2 L → Fe(TPP)L2 + Cl−
The complex is widely studied as a catalyst.
References
Chelating agents
Tetrapyrroles
Macrocycles
Phenyl compounds | Iron(tetraphenylporphyrinato) chloride | [
"Chemistry"
] | 304 | [
"Organic compounds",
"Chelating agents",
"Macrocycles",
"Process chemicals"
] |
63,467,627 | https://en.wikipedia.org/wiki/Sam%20Curry | Sam Curry (born October 17, 1999) is an American ethical hacker, bug bounty hunter, and founder. He is best known for his contributions to web application security through participation in bug bounty programs, most notably finding critical vulnerabilities in 20 different auto manufacturers including Porsche, Mercedes-Benz, Ferrari, and Toyota. In 2018, Curry began working as a security consultant through his company Palisade where he disclosed vulnerability publications for security findings in Apple, Starbucks, Jira, and Tesla.
In 2021, Palisade was acquired by Yuga Labs where Curry currently works as a security engineer. In 2023, Curry was detained and summoned to testify within a Grand Jury by the IRS-CI and DHS on wrongful suspicion of running a high-profile phishing website.
Curry has spoken on ethical hacking, web application security, and vulnerability disclosure at conferences including DEFCON, Black Hat Briefings, Kernelcon, and null.
Biography
Curry grew up in Omaha, Nebraska and attended Elkhorn High School. He began hacking at the age of 12, ethically disclosing vulnerabilities to various vendors over email. At University of Nebraska Omaha, Curry worked with students through the cyber security club NULLify.
Publications and articles
"Researchers Secure Bug Bounty Payout to Help Raise Funds for Infant’s Surgery". vice.com. Retrieved June 2, 2021.
"Pega Infinity hotfix released after researchers flag critical authentication bypass vulnerability" portswigger.net. Retrieved June 2, 2021.
"We Hacked Apple for 3 Months: Here’s What We Found". samcurry.net. Retrieved April 9, 2021.
"Filling in the Blanks: Exploiting Null Byte Buffer Overflow for a $40,000 Bounty". samcurry.net. Retrieved November 3, 2019.
"Web Hackers vs. The Auto Industry: Critical Vulnerabilities in Ferrari, BMW, Rolls Royce, Porsche, and More". samcurry.net. Retrieved November 26, 2023.
"Hackers Could Have Scored Unlimited Airline Miles by Targeting One Platform". wired.com. Retrieved March 23, 2024.
"Hackers Found a Way to Open Any of 3 Million Hotel Keycard Locks in Seconds". wired.com. Retrieved March 23, 2024.
References
Hackers
1999 births
Living people
People from Omaha, Nebraska | Sam Curry | [
"Technology"
] | 481 | [
"Lists of people in STEM fields",
"Hackers"
] |
63,468,037 | https://en.wikipedia.org/wiki/Estrone%20phosphate | Estrone phosphate (E1P), or estrone 3-phosphate, is an estrogen and steroid sulfatase inhibitor which was never marketed. It has similar affinity for steroid sulfatase as estrone sulfate and acts as a competitive inhibitor of the enzyme. In contrast to estrone sulfate however, it is not hydrolyzed by steroid sulfatase and is instead metabolized by phosphatases.
See also
List of estrogen esters § Estrone esters
Estradiol phosphate
Estriol phosphate
References
Abandoned drugs
Estrone esters
Phosphate esters
Sex hormone esters and conjugates
Steroid sulfatase inhibitors
Synthetic estrogens | Estrone phosphate | [
"Chemistry"
] | 141 | [
"Drug safety",
"Abandoned drugs"
] |
63,470,073 | https://en.wikipedia.org/wiki/NGC%20542 | NGC 542 is a spiral galaxy in the constellation Andromeda, which is approximately 215 million light years from the Milky Way. Together with the galaxies NGC 529, NGC 531, and NGC 536, it forms the Hickson Compact Group 10, abbreviated HCG 10. It was discovered by Irish astronomer R.J. Mitchell in 1885.
See also
List of NGC objects (1–1000)
References
External links
Spiral galaxies
0542
Andromeda (constellation)
005360 | NGC 542 | [
"Astronomy"
] | 100 | [
"Andromeda (constellation)",
"Constellations"
] |
63,471,020 | https://en.wikipedia.org/wiki/Linbury%20Prize%20for%20Stage%20Design | The Linbury Prize for Stage Design is the most prestigious prize for emerging stage designers with professional focus on theatre, dance, and opera companies in the United Kingdom. Since 1987, it has been awarded every two years.
History
In 1973, Lord Sainsbury of Preston Candover KG (John Sainsbury) and his wife Lady Sainsbury, CBE, the former ballerina Anya Linden, founded the charitable Linbury Trust (Linbury is a portmanteau combining the names Linden and Sainsbury). The Linbury Prize, intending to launch the careers of young stage designers, is funded entirely by the Linbury Trust and supported by a group of advocates, endorsing its aims. The first Linbury Prizes were awarded in 1987.
Selection
The selection to determine the winners follows a procedure:
The designs of entrants, recent graduates of theatre design courses at colleges across the United Kingdom, are presented to a group of three jurors.
The designs of more than twelve candidates are selected.
The selected candidates present their designs to the directors and choreographers of three previously selected, commissioning British theatre, opera house, or dance companies.
Each company selects three designers with whom they desire to collaborate.
The twelve finalists are asked to create designs for the companies forthcoming productions. Their expenses are covered by a sum supplied by the Linbury Trust.
Four designs, one for each production, are selected. Their creators are the winners of the Linbury Prize for Stage Design, which is the commission to realise the selected designs on stage. Financial support for the winner as well as for the commissioning company is supplied by the Linbury Trust.
Winners
From 1987 until 1995, three prizes, including the overall winner (OW), were awarded biennially.
Since 1997, four prizes are awarded biennially.
The following designers are awarded winners:
Website
Official website
References
Awards established in 1987
Fellowships
Design awards | Linbury Prize for Stage Design | [
"Engineering"
] | 381 | [
"Design",
"Design awards"
] |
63,471,254 | https://en.wikipedia.org/wiki/Huawei%20P40 | Huawei P40 is a line of high-end Android-based smartphones manufactured by Huawei. Unveiled on 26 March 2020, they succeed the Huawei P30 in the company's P series line.
Design
The P40 and P40 Pro are constructed with anodized aluminum for the frame, while the back uses Gorilla Glass. The P40 Pro+ uses ceramic for both the frame and the back. The display is flat on the P40, and curved on all sides on the P40 Pro and P40 Pro+; Huawei calls this a Quad-Curve Overflow Display. The top left corner of the display has a pill-shaped cutout for the front-facing camera and ambient/proximity sensors; it also accommodates the infrared face unlock system on the P40 Pro and P40 Pro+.
As on the P30 Pro, the P40 Pro and P40 Pro+ replace the traditional earpiece speaker with an "electromagnetic levitation" speaker that vibrates the top of the phone's screen, and have an IR blaster on the top edge. A rectangular module houses the rear cameras, which protrudes slightly from the back panel.
The P40 and P40 Pro are available in Silver Frost, Blush Gold, Deep Sea Blue, Ice White and Black, while the P40 Pro+ is available in Ceramic White or Ceramic Black. Additionally, the P40 has an IP53 rating while the P40 Pro and P40 Pro+ have an IP68 rating.
Specifications
Hardware
The P40 series is powered by the HiSilicon Kirin 990 5G processor, meaning that all models have 5G connectivity, unlike the successor P50 series that lacked 5G due to the United States sanctions that came into effect in September 2020. However, only "sub-6" 5G is available on the P40, meaning the P40 series is not compatible with ultra-fast millimeter-wave (mmWave) networks. The Kirin 990 5G is assisted by the Mali-G76 MP16 GPU. The P40 has 6 or 8 GB of LPDDR4X RAM, while the P40 Pro & P40 Pro+ have 8 GB of LPDDR4X RAM. All models have UFS 3.0: the P40 has 128 or 256 GB, the P40 Pro has 128, 256 or 512 GB and the P40 Pro+ has 256 or 512 GB. Expansion is supported up to 256 GB via Huawei's proprietary Nano Memory card.
The P40's display is carried over from the P30, a 6.1" (154.94mm) 19.5:9 1080p (1080 × 2340) OLED with a 60 Hz refresh rate. The P40 Pro and P40 Pro+ use a larger 6.58" (167.13mm) 19.8:9 1080p+ (1200 × 2640) OLED and a 90 Hz refresh rate, as well as support for HDR10 and DCI-P3. In addition to the infrared face unlock system, all P40 models have an optical (under-screen) fingerprint sensor; Huawei claims the sensor is 30% larger and faster than the P30's.
The P40 uses a 3800 mAh battery, while the P40 Pro and P40 Pro+ use a larger 4200 mAh battery. Fast charging is supported on all models, however the P40 does not support wireless charging. The P40 can charge wired up to 22.5 W while the P40 Pro and P40 Pro+ have a max rate of 40 W. Both the P40 Pro and P40 Pro+ are also capable of reverse wireless charging at 27 W, but the P40 Pro+ can charge faster wirelessly at 40 W whereas the P40 Pro can only charge wirelessly at 27 W.
Camera
The Huawei P40 series features Leica optics, and the wide lens on all models is a new "Ultra Vision" 50 MP sensor. Like the P30, the wide lens uses a "SuperSpectrum" image sensor, whose color filter array uses yellow sub-pixels instead of green. Huawei stated that this would allow more light to be captured, and enhanced absorption of red and green colors.
The P40's rear camera array consists of a 50 MP wide lens, a 16 MP ultrawide lens and an 8 MP telephoto lens with 3x optical zoom. The P40 Pro increases the resolution of the ultrawide sensor to 40 MP, replaces the standard telephoto lens with a 12 MP periscope sensor capable of 5x optical zoom, and adds a time-of-flight sensor.
The P40 Pro+ has two 8 MP telephoto lenses, a standard sensor with 3x optical zoom and a periscope sensor with 10x optical zoom while retaining the time-of-flight sensor. The front-facing camera uses a 32 MP sensor which has autofocus on the P40 Pro and P40 Pro+; an additional depth sensor allows for the face unlock.
For both photo and video, pixel binning is used for improved low-light sensitivity, and video can be captured from the wide-angle and telephoto sensors simultaneously with directional audio computed from three omnidirectional microphones.
The cameras benefit from an XD Fusion Image Engine which enables advanced computational photography, as well as an "Octa" phase-detection autofocus system for faster autofocus and improved white balance sensors on the P40 Pro+. The software is also improved with a new Golden Snap feature that takes a burst of HDR+ photos and automatically picks the best shots. A Profoto studio light will be available as an accessory as well.
Software
The P40 series originally shipped with EMUI 10.1, which is based on the Android 10 source code. In January 2022, the smartphone received an upgrade to EMUI 12. An additional upgrade to EMUI 13 was expected, but had not been confirmed as of summer 2023. Starting in December 2020, Chinese smartphones could be migrated from EMUI to HarmonyOS 2, and in July 2023 they received an upgrade to HarmonyOS 3.1.
Due to the ongoing United States sanctions against Huawei, international models of the P40 did not ship with, or support, Google Mobile Services—the proprietary software suite (including Google Play-branded software) shipped on certified Android devices. Huawei was also not allowed to market the device using the Android trademark.
The P40 series supports Huawei Mobile Services and uses Huawei AppGallery as its main app store. Furthermore, a new app known as Petal Search was introduced, which includes web search via France-based Qwant and Russia-based Yandex, as well as the ability to search for third-party apps via other Android app stores and APK mirroring websites. The P40 series introduces a new in-house voice assistant, Celia, in selected markets, which also includes integration with the device's AI Lens features.
Reception
The P40 Pro gets a Photo score of 140 points and a best Video score of 105 points from DxOMark.
See also
List of longest smartphone telephoto lenses
References
Huawei smartphones
Mobile phones introduced in 2020
Android (operating system) devices
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording
Mobile phones with infrared transmitter
Discontinued flagship smartphones | Huawei P40 | [
"Technology"
] | 1,529 | [
"Discontinued flagship smartphones",
"Flagship smartphones"
] |
63,471,410 | https://en.wikipedia.org/wiki/Pallas-1 | The Pallas-1 () is a medium-lift orbital launch vehicle under development by Galactic Energy. It features seven Welkin engines burning RP-1 and liquid oxygen (kerolox) in its first stage. The first stage will have legs and grid fins to allow for stage recovery by vertical landing (much like the SpaceX Falcon 9).
Pallas-1 is planned to be capable of placing a 5-tonne payload into low Earth orbit (LEO), or a 3-tonne payload into a 700-kilometer Sun-synchronous orbit (SSO). The first launch of the rocket was scheduled to take place in November 2024, while an initial attempt at first stage recovery using landing legs is slated for 2025.
Using three Pallas-1 booster cores as its first stage, Pallas-1B () will be capable of putting a 17.5-tonne payload into low Earth orbit.
Launches
Future Launches
References
Space launch vehicles of China
VTVL rockets
Proposed reusable launch systems | Pallas-1 | [
"Astronomy"
] | 213 | [
"Rocketry stubs",
"Astronomy stubs"
] |
63,471,884 | https://en.wikipedia.org/wiki/Carlo%20Masi | Ruggero Freddi (born October 6, 1976) is an Italian mathematics lecturer and former gay pornographic film actor known professionally as Carlo Masi.
Early life and education
Freddi was born in Rome in 1976 to a poor family. His parents divorced when he was three years old. At the age of 14, he began to work out at a local gym, practicing bodybuilding assiduously. In 2002, when he was about to complete his first cycle of study at the Sapienza University of Rome, he moved to Canada, and subsequently to New York.
Career
In 2003, Masi completed a Master of Science (MSc) degree in computer engineering at the Sapienza University of Rome and worked in an artificial intelligence laboratory.
Pornography
In 2004, after being contacted by a Colt Studio Group (CSG) recruiter, he made his debut in the gay pornography industry participating in his first porn movie, Big N 'Plenty. After his debut, he signed an exclusive model contract with CSG. He has always promoted safe sex, fraternising with the Italian LGBT community.
In 2006, he was selected to appear on the cover of COLT 40, a coffee table book published to celebrate the fortieth anniversary of the production company.
In 2007, Masi and his future husband, Adam Champ (), were selected to appear on the cover of the Damron 2007 Men's Travel Guide.
In 2008, CSG and Calaexotic released a dildo reproduction of Masi's penis. That same year, he was named the first and only Colt Man Emeritus and his contract was extended to a lifetime one. In 2008, Masi and Champ, were selected to appear on the cover of Adam Gay Film & Video Directory Magazine.
During his porn career, he was a guest on national Italian TV shows such as , L'Infedele and . Moreover, he was featured in several tours across America, Mexico and Europe to promote the CSG brand. His porn career lasted six years (from age 28 to 34). Following a disagreement with Colt in 2009, Masi retired from the pornography industry.
He then entered the theatre industry. In 2010, he was officially announced as a permanent member of the cast of Saturday Night Live Italia but he never appeared on the show.
In 2011, he was included in the anthologies Porn from Andy Warhol to X-Tube and Gay Porn Heroes: 100 Most Famous Porn Stars. In 2013, he was interviewed for the documentary HUSTLABALL BERLIN - A Documentary That Bares All. In 2014, he was included in the coffee table book produced by Colt entitled Hairy Chested Men.
Theatre
In 2009, he made his theatre debut with Senzaparole, a reinterpretation of Samuel Beckett's Act Without Words I, directed by and staged in Bologna with the theatre company. and later in Rome at the .
Academia
After working in the theatre, Masi decided to return to the Sapienza University of Rome. There he earned a Bachelor of Science degree (cum laude) in mathematics, with a score of 110/110 and then a Master of Science degree (cum laude) in mathematics with a score of 110/110. In 2020, he completed a Ph.D. in Mathematical Models for Engineering, Electromagnetism and Nanosciences at Sapienza University of Rome focusing on the application of Morse theory to a Dirichlet problem traced back to Poisson equations. His doctoral advisors were Angela Pistoia and .
While he was working on his doctorate, he was a lecturer for Analysis 1 and Analysis 2 courses at the Faculty of Engineering at the Sapienza University of Rome.
Media attention
In 2017, an article published by la Repubblica brought to light his past as a porn actor, causing a media frenzy. The story was picked up by numerous newspapers around the world.
In 2020, writer Strega Prize winner published La natura è innocente – Due vite quasi vere. This book is a double biography, told in alternate chapters, one of which is that of Ruggero Freddi.
In 2023, he returned to the media spotlight, after winning a lawsuit for unfair dismissal against his former employers at the Sapienza University of Rome because they fired him without cause and refused to pay him for work done in 2019. The university was ordered to pay him €2,500 for his hours worked and damages of €1,500 for "unjustified dismissal".
Personal life
In 2015, Masi married Prince Giovanni Ravaschieri Fieschi in Porto. Del Drago died in 2016.
During his participation at Pomeriggio Cinque, he proposed to his partner, . The civil union was celebrated on May 4, 2018, and was broadcast live on Pomeriggio Cinque.
Selected videography
Awards
See also
LGBT people in science
List of actors in gay pornographic films
References
Citations
Bibliography
External links
1976 births
21st-century Italian male actors
21st-century Italian mathematicians
Gay academics
Gay scientists
Gay pornographic film actors
Italian male pornographic film actors
Italian bodybuilders
Italian male stage actors
LGBTQ bodybuilders
Italian LGBTQ scientists
Italian gay sportsmen
Italian gay actors
Topologists
Living people
Male actors from Rome
Sapienza University of Rome alumni
Academic staff of the Sapienza University of Rome
21st-century Italian LGBTQ people | Carlo Masi | [
"Mathematics"
] | 1,084 | [
"Topologists",
"Topology"
] |
63,472,570 | https://en.wikipedia.org/wiki/Antiprion%20drug | Antiprion drugs are drugs that work against prions. The discovery of antiprion drugs is a priority because prion diseases are untreatable and fatal. Therefore, it is a therapeutic priority to find effective anti-prion drugs.
Mechanism of action
The disease progression in prion diseases is probably due to the conformational change of the prion protein (PrP). PrP changes from alpha-helical conformation to a disease-associated, mainly beta-sheeted scrapie isoform (PrPSc), which forms amyloid aggregates. The drugs that contain N′-benzylidene-benzohydrazide core structure are likely to slow down this progression. Drugs that target PrPC, the normal prion isoform, are also hypothesized to delay the progression of prion diseases.
References
Anti-infective agents | Antiprion drug | [
"Chemistry"
] | 182 | [
"Anti-infective agents",
"Chemicals in medicine"
] |
73,582,306 | https://en.wikipedia.org/wiki/Coumarin%20derivatives | Coumarin derivatives are derivatives of coumarin and are considered phenylpropanoids. Among the most important derivatives are the 4-hydroxycoumarins, which exhibit anticoagulant properties, a characteristic not present for coumarin itself.
Some naturally occurring coumarin derivatives include umbelliferone (7-hydroxycoumarin), aesculetin (6,7-dihydroxycoumarin), herniarin (7-methoxycoumarin), psoralen and imperatorin.
4-Phenylcoumarin is the backbone of the neoflavones, a type of neoflavonoids.
Coumarin pyrazole hybrids have been synthesized from hydrazones, carbazones and thiocarbazones via Vilsmeier Haack formylation reaction.
Compounds derived from coumarin are also called coumarins or coumarinoids; this family includes:
brodifacoum
bromadiolone
difenacoum
auraptene
ensaculin
phenprocoumon (Marcoumar)
PSB-SB-487
PSB-SB-1202
scopoletin can be isolated from the bark of Shorea pinanga
warfarin (Coumadin)
Coumarin is transformed into the natural anticoagulant dicoumarol by a number of species of fungi. This occurs as the result of the production of 4-hydroxycoumarin, then further (in the presence of naturally occurring formaldehyde) into the actual anticoagulant dicoumarol, a fermentation product and mycotoxin. Dicoumarol was responsible for the bleeding disease known historically as "sweet clover disease" in cattle eating moldy sweet clover silage. In basic research, preliminary evidence exists for coumarin having various biological activities, including anti-inflammatory, anti-tumor, antibacterial, and antifungal properties, among others.
Uses
Medicine
Warfarin – a coumarin – with brand name, Coumadin, is a prescription drug used as an anticoagulant to inhibit formation of blood clots, and so is a therapy for deep vein thrombosis and pulmonary embolism. It may be used to prevent recurrent blood clot formation from atrial fibrillation, thrombotic stroke, and transient ischemic attacks.
Coumarins have shown some evidence of biological activity and have limited approval for few medical uses as pharmaceuticals, such as in the treatment of lymphedema. Both coumarin and 1,3-indandione derivatives produce a uricosuric effect, presumably by interfering with the renal tubular reabsorption of urate.
Laser dyes
Coumarin dyes are extensively used as gain media in blue-green tunable organic dye lasers. Among the various coumarin laser dyes are coumarins 480, 490, 504, 521, 504T, and 521T. Coumarin tetramethyl laser dyes offer wide tunability and high laser gain, and they are also used as active medium in coherent OLED emitters. and as a sensitizer in older photovoltaic technologies.
References
Coumarins
Phenylpropanoids | Coumarin derivatives | [
"Chemistry"
] | 698 | [
"Biomolecules by chemical classification",
"Phenylpropanoids"
] |
73,582,948 | https://en.wikipedia.org/wiki/Ludmila%20Slav%C3%ADkov%C3%A1 | Ludmila Slavíková or Ludmila Slavíková-Kaplanová (23 February 1890 – 18 February 1943) was a Czech geologist, mineralogist and crystallographer. She was director of the Department of Mineralogy and Petrology at the National Museum in Prague. After the German occupation of Czechoslovakia, she became active in the resistance. Arrested in February 1943, she was deported to the Auschwitz concentration camp where she died shortly thereafter.
Life and work
Ludmila Kaplanová was born in Prague to Viktorin Kaplan and Bohumila Kaplanová-Holoubková in 1890. She was educated in Prague, which was then part of Austria-Hungary. She studied science at Charles University in Prague and earned a Ph.D. in mathematics and physics in 1914. As part of her thesis work, she investigated pyrargyrite crystals. She briefly worked as a school teacher in Prague and Pardubice. In 1917, she married František Slavík, professor of mineralogy at the Czech University of Prague, and she collaborated with him in the publication of a monograph on the Ordovician iron ore deposits of Bohemia. Between 1921 and 1939, she worked at the National Museum in Prague, where she headed the Department of Mineralogy and Petrology.
Her research work covered various topics, such as the study of crystals of organic compounds and minerals from Czechoslovakia, among others. She was the author of several scientific publications and textbooks on mineralogy. For the centenary of the National Museum in Prague, she wrote a series of articles on the history of the museum's mineral collections.
In 1943, she and her husband were detained by the Nazis for their resistance activities. Two weeks after her arrest, Slavíková died in the Auschwitz concentration camp.
References
1890 births
1943 deaths
Charles University alumni
Czech mineralogists
Scientists from Prague
Women geologists
20th-century Czech women
Czech resistance members
Resistance members who died in Nazi concentration camps
Czech people who died in Auschwitz concentration camp
Crystallographers | Ludmila Slavíková | [
"Chemistry",
"Materials_science"
] | 405 | [
"Crystallographers",
"Crystallography"
] |
73,586,885 | https://en.wikipedia.org/wiki/Barnard%205 | Barnard 5 is a dark nebula in the constellation of Perseus. Barnard 5 has several star forming regions inside of it. The right ascension and declination is 0h.47m and +32°53'
References
Cosmic dust
Dark nebulae
Barnard objects | Barnard 5 | [
"Astronomy"
] | 54 | [
"Outer space",
"Astronomy stubs",
"Nebula stubs",
"Astronomical objects",
"Cosmic dust"
] |
73,587,150 | https://en.wikipedia.org/wiki/Bioreceptivity | Bioreceptivity is defined as "the ability of a material to be colonized by living organisms." First defined by Guillitte in 1995 as a new term in ecology to discuss the beneficial applications of building materials for ecological uses. Previous understandings termed the colonization of organisms as "degradation," implying a negative connotation, leading to the creation of "bioreceptivity" for positive benefits of colonization on materials. It is an interdisciplinary field of study between materials science and ecology.
Bioreceptive design is commonly mistaken for biomimicry, or nature inspired design. Marco Cruz and Richard Beckett provide an alternative explanation known as architectural bark, in which it is both nature-inspired and nature-integrated where colonization by the microbiome and organisms plays a role in the architectural design. Bioreceptivity is different from green infrastructure, such as green roofs, green walls, and storm water management, but has been observed to be related to these research areas in architecture. Bioreceptive design has led to further research studies in concrete materials for use in urban environments through walls and non-green spaces. However, bioreceptive designs have implications outside creating new green spaces, and can be used for conservation biology and ecological restoration.
Urban ecologies
A more recent trend in architectural design has been an effort to include green spaces in public areas to improve the connection between people and nature. However the creation of green spaces includes pressures such as space, natural resource demand, and development limitations that reduce the amount of green spaces available in urban environments. Land space is limited due to increased urbanization and human dominated landscapes reduce regional biodiversity. To adapt to these challenges, designers are utilizing the vertical spaces provided by urban architecture to promote biodiversity. To address the issue of space availability, wall space has been shown to be a promising area to improve vegetation and native flora, creating an effective method for natural conservation. A "Nature takes its course," method can also allow for vegetation to naturally colonize new urban spaces without economic constraints on landscape design and vegetation selection.
In conservation
Bioreceptive designs help promote biodiversity, and have been used outside of the architectural context for implications in conservation biology.
Examples of Bioreceptive Design
Urban Reef is a company founded by Pierre Oskam and Max Latour to create habitats and promote biodiversity in urban environments. The company utilizes 3D printing with natural materials to create "reef" structures that provide microclimates and nutrients for organisms in city environments.
EcoShape is building Artificial Reefs using ceramics, geo-textiles, bio-rocks, and 3D printing to promote coral reef growth. Utilizing recycled materials they are able to design reef balls that can promote niche habitats for plants and coral, while providing hollow structures for fish and mammals.
Jason deCaires Taylor is an artist who utilizes bioreceptive and pH neutral concrete that promotes coral reef growth and provides ecological restoration in marine environments. Additionally their work has led to the creation of the world's first underwater sculpture park that provides a non-invasive artistic experience without disrupting the marine environment. Taylor's pieces integrate messages on the complexity of human and the environment, while also integrating reflection on conservation.
See also
Living Walls
Restoration Ecology
Urban Ecology
References
Ecology | Bioreceptivity | [
"Biology"
] | 649 | [
"Ecology"
] |
73,587,993 | https://en.wikipedia.org/wiki/Blockscale | Intel Blockscale was a brand of crypto-mining accelerator ASIC sold by the U.S. chip manufacturer Intel. The Blockscale product debuted in June 2022, and was cancelled by Intel in April 2023. Intel has stated that it will continue to supply chips to existing customers until April 2024.
The Blockscale chips were SHA-256 hardware accelerators designed for proof-of-work calculations. According to Intel, they were capable of up to 580 GH/s with a power consumption of up to 22.7 W, and a claimed efficiency of up to 26 J/TH. The product came in three variants: the Blockscale 1120, 1140, and 1160.
References
Intel products
Hardware acceleration
Cryptographic hardware
Bitcoin
2022 establishments in the United States
2023 disestablishments in the United States | Blockscale | [
"Technology"
] | 178 | [
"Computing stubs",
"Hardware acceleration",
"Computer hardware stubs",
"Computer systems"
] |
73,588,029 | https://en.wikipedia.org/wiki/Osmium%28III%29%20bromide | Osmium(III) tribromide is a binary inorganic compound with the chemical formula .
Synthesis
Decomposition of osmium tetrabromide under vacuum heating:
Physical properties
The compound forms dark-grey crystals. Insoluble in water.
References
Bromides
Platinum group halides
Osmium compounds
Metal halides | Osmium(III) bromide | [
"Chemistry"
] | 64 | [
"Bromides",
"Inorganic compounds",
"Metal halides",
"Salts"
] |
73,588,114 | https://en.wikipedia.org/wiki/Nostr | Nostr (acronym for Notes and Other Stuff Transmitted by Relays) is an open protocol for decentralized message transmission, with the intention to be able to resist internet censorship while maintaining session integrity. "Noster" can also be translated as "our" or "ours" from Latin. The protocol achieves decentralization through users publishing content via a cryptographic key pair to various "relays", a WebSocket server which produces an activity stream of received content from users that subscribe to it. This allows the network to verify users and achieve account portability on Nostr, as users have to sign all posts using their key pair to utilize its identity. This requires users maintaining personal copies of their keys to have complete control over its identity, however services using Nostr can "remember" a private key for repeated use.
The Nostr protocol was first written in 2020 by Brazilian open source developer Giovanni Torres Parra, known by the pseudonym "fiatjaf". Nostr was created as a result of perceived moderation issues on Twitter, as well as technical and cultural disagreements with other similar protocols such as ActivityPub and Secure Scuttlebutt.
Protocol
As an open standard designed to be implemented with little difficulty, there are a number of third-party apps and utilities that support Nostr, the majority of which is free and open-source.
Data on the Nostr protocol is stored in JSON blobs called Events, which is the only kind of object on the Nostr protocol. Users are identified by their public key, tagged as an "npub" key. Different extensions to the Nostr protocol are called Nostr Implementation Possibilities, or "NIPs". One of these extensions provide integration with the Lightning Network, a separate payment protocol that operates over the Bitcoin network, allowing Nostr users to send and request small payments (nicknamed "Zaps") among other users. Other NIPs include ways to add a human-readable alias to an npub key using a well-known URI hosted on a web server, a method that is also used by ActivityPub and the AT Protocol.
Users
The Nostr client Damus is a microblogging social networking app akin to Twitter. Damus was the first Nostr app to be listed on the App Store.
Nostr is primarily popular with cryptocurrency communities, primarily Bitcoin users. Jack Dorsey, the co-founder of Twitter, has endorsed and financially supported the development of Nostr by donating approximately $250,000 worth of bitcoin to the developers of the project. Tidal, a music streaming service owned by Block, Inc. (itself founded by Dorsey and who is its current chairman and CEO), has implemented Nostr support for its music embed widgets, allowing users with a Nostr public key linked to their account and a browser extension that can authenticate Events on Nostr to listen to the full song through the embed.
Some Nostr apps have been banned in China, which their developers have described as 'expected' and a success.
As a result of its ability to quickly and discreetly create accounts and publish posts to relays, Nostr can propagate spam much easier if left unchecked. A notable example includes a case where multiple protocol bridges have been used to conduct spam waves on the Bluesky social network by creating posts on Nostr, bridging the post to ActivityPub and bridging it again to Bluesky.
See also
ActivityPub, a decentralized social networking protocol
AT Protocol, a similar protocol used by Bluesky
References
External links
Social media
Social networking services
Public-domain software
Distributed computing projects
Internet properties established in 2020
Cryptographic protocols
Open standards
Open source projects
Internet censorship | Nostr | [
"Technology",
"Engineering"
] | 770 | [
"Distributed computing projects",
"Information technology projects",
"Computing and society",
"Social media"
] |
73,588,472 | https://en.wikipedia.org/wiki/Osmium%20heptafluoride | Osmium heptafluoride is a possible inorganic chemical compound of osmium metal and fluorine with the chemical formula . It was first reported in 1966 by the reaction of fluorine and osmium at 600 °C and 400 atm, but no purported synthesis could be reproduced in 2006, giving only osmium hexafluoride instead.
Physical properties
If it exists, osmium(VII) fluoride is supposedly a bluish-yellow hygroscopic substance, extremely unstable. The compound starts decomposing at –100 °C. It should be stored in a nickel vessel at the temperature of liquid nitrogen.
Chemical properties
Osmium heptafluoride decomposes to osmium hexafluoride when slightly heated:
References
Osmium compounds
Fluorides
Metal halides
Hypothetical chemical compounds | Osmium heptafluoride | [
"Chemistry"
] | 166 | [
"Inorganic compounds",
"Hypotheses in chemistry",
"Salts",
"Inorganic compound stubs",
"Theoretical chemistry",
"Metal halides",
"Hypothetical chemical compounds",
"Fluorides"
] |
73,589,042 | https://en.wikipedia.org/wiki/Arokia%20Nathan | Arokia Nathan is an engineer, author and academic. He is an expert in the field of electrical engineering and digital display technology.
Education
Nathan studied at the University of Alberta, where he received his Ph.D. in Electrical Engineering in 1988.
Career
Following Nathan's graduation, he spent time working at both LSI Logic Corporation and ETH Zurich in the 1990s, before he joined the University of Waterloo in 1997 to chair DALSA/Natural Sciences and Engineering Research Council following the establishment of the university's Giga-to-Nanoelectronics Centre. In 2001, he was recognised by the Canadian Natural Sciences and Engineering Research Council with the E.W.R. Steacie Memorial Fellowship. In 2004, he was awarded the Canada Research Chair in nano-scale flexible circuits. He then moved to University College London in 2006 to take up the role of Chair of Nanotechnology at the London Centre for Nanotechnology. While at UCL, he was the recipient of the Royal Society Wolfson Research Merit Award.
In 2011, Nathan was recruited by the University of Cambridge as Chair of Photonic Systems and Displays, having previously worked at University College London. At Cambridge, Arokia and his team developed ultra-low power transistor electronics in 2016 and 2019, which would go on to be used in various wearables and devices using Internet of Things technology. It was believed that the ultralow power transistors could operate for years, without the need for battery replacement.
Prof. Nathan is currently in the School of Information Science and Engineering at Shandong University in Jian City, China.
In 2020, he was the recipient of J. J. Ebers Award, for his work with thin-film transistor and flexible/foldable electronics integration strategies.
Nathan's research and industry foresight has led to the creation of numerous companies, with a collective venture capital investment of over US$100 million. In 2022, he became a Fellow at the Royal Academy of Engineering.
References
Living people
Year of birth missing (living people)
Electrical engineers
University of Alberta alumni
Academics of the University of Cambridge
Academic staff of the University of Waterloo
Academics of University College London | Arokia Nathan | [
"Engineering"
] | 442 | [
"Electrical engineering",
"Electrical engineers"
] |
73,590,152 | https://en.wikipedia.org/wiki/IC%202631 | IC 2631 or Chamaeleon Cloud is a bright reflection nebula in the southern constellation of Chamaeleon. The nebula is lit up by a massive pre-main sequence star called HD 97300 at a distance of ~630 light years. It can be found 14.9° above the galactic plane of the Milky Way. IC 2631 can be easily seen in the southern hemisphere for the most part of the year.
References
Reflection nebulae
Chamaeleon
2631 | IC 2631 | [
"Astronomy"
] | 99 | [
"Nebula stubs",
"Chamaeleon",
"Astronomy stubs",
"Constellations"
] |
73,590,202 | https://en.wikipedia.org/wiki/Technetium%28V%29%20fluoride | Technetium pentafluoride is a binary inorganic chemical compound of technetium metal and fluorine with the chemical formula .
Synthesis
The compound can be synthesised by heating of technetium powder in a jet of fluorine diluted with nitrogen:
Another way to prepare it is the effect of iodine on technetium hexafluoride solution in iodine pentafluoride:
Physical properties
Technetium pentafluoride forms yellow crystals of orthorhombic crystal system. It reacts with water, and is volatile.
Chemical properties
The compound is hydrolyzed by water, disproportionating to more stable technetium compounds:
References
Technetium compounds
Fluorides
Metal halides | Technetium(V) fluoride | [
"Chemistry"
] | 152 | [
"Inorganic compounds",
"Fluorides",
"Metal halides",
"Salts"
] |
73,590,419 | https://en.wikipedia.org/wiki/Precoccinelline | Precoccinelline is an alkaloid produced by the Coccinella septempunctata, also known as the seven-spot ladybird. The alkaloid is released from the joints in C. septempunctata legs when it is provoked to deter predators such as ants or birds. It binds to both insect and mammalian nicotinic acetylcholine receptors, giving it use as an insecticide or as a therapy to treat drug dependence.
Biosynthesis
It was determined that precoccinelline is produced de novo in the C. septempunctata as their diet, which is composed of aphids, does not contain this alkaloid. While the exact biosynthesis has not been fleshed out, precoccinelline is thought to be of polyketide origin. The hypothesized biosynthesis involves condensation of six acetates and methyl addition.
Chemical synthesis
2,6-lutidine (1) is used as starting material, and its treatment with β-bromo-propionaldehyde dimethyl acetal in ether produces a monolithium derivative. In the presence of 2,6-lutidine in excess, the monolithium derivative becomes an acetal (2). Treatment of the acetal with phenyl-lithium and then adding an ethereal solution of acetonitrile produces the crude ketone (3), followed by immediate transformation into the diacetal (4). Using sodium-isoamyl alcohol, the diacetal can be reduced to give the cis piperidine (5). The trans-isomer of the cis piperidine can be isolated and hydrolyzed using aqueous hydrochloric acid to yield the ketol (6). The ketol can then be cyclized with the use of acetic acid and pyrrolidine in refluxing tetrahydrofuran which gives a mixture of ketones. Separation of structure 7 from the mixture and then treatment with methyllithium in ether to produce a carbinol (8). Dehydrating the carbinol with thionyl chloride in methylene chloride gives olefin which can be hydrogenated to produce precoccinelline.
Mechanism of action
Precoccinelline is an alkaloid which acts as an inhibitor of nicotinic acetylcholine receptors (nAChRs). It binds to an allosteric site on nAChRs― a site separate from the ACh recognition site. Of the secreted ladybird alkaloids, precoccinelline was the most potent inhibitor, acting via a non-competitive mechanism.
Targeting nAChRs has several implications including developing insecticides and modulating drug dependence relating to the reward pathway in the brain.
References
Heterocyclic compounds with 3 rings
Nitrogen heterocycles
Alkaloids
Acetylcholinesterase inhibitors | Precoccinelline | [
"Chemistry"
] | 621 | [
"Organic compounds",
"Biomolecules by chemical classification",
"Natural products",
"Alkaloids"
] |
73,590,520 | https://en.wikipedia.org/wiki/2023%20Tanzania%20Marburg%20virus%20disease%20outbreak | The 2023 Tanzania Marburg virus disease outbreak lasted from March until June. It was first reported on 21 March 2023 by the Ministry of Health of Tanzania and the first time that Tanzania reported an outbreak of Marburg virus disease. On 2 June 2023, Tanzania declared the outbreak over.
Background
Marburg virus disease is a viral hemorrhagic fever caused by the Marburg virus, with a case fatality ratio of up to 88 percent. Symptoms are similar to Ebola virus disease and like Ebola, Marburg virus spreads through contact with body fluids of infected people. There are no vaccines or antiviral treatments for Marburg. While there had not been an outbreak in Tanzania, the virus had been identified in neighboring countries and the reservoir, the Egyptian fruit bat, is known to be present there.
Outbreak
On 16 March 2023, the Ministry of Health of Tanzania announced that seven cases and five deaths from an unknown disease had been reported in two villages in Bukoba district, Kagera region, northern Tanzania. The cases were later confirmed as Marburg virus infection and announced as an outbreak on 21 March 2023. Though there is an ongoing outbreak of marburg virus disease in Equatorial Guinea, so far, there is no evidence of an epidemiological link between the two outbreaks.
As of 8 May, nine cases were reported, including eight laboratory confirmed cases and one probable case. The cases had all been in the Bukoba district of Kagera Region and appeared to be epidemiologically linked. Per an 8 May 2023 press release from the World Health Organization, three patients recovered and six died; cases ranged in age from 1 to 59 years old (median 35-year-old), and two cases were among healthcare workers (one of which died). Males were the most affected (6 of the 9 cases). On 2 June 2023, Tanzania declared the outbreak over.
See also
2023 Marburg virus disease outbreak in Equatorial Guinea
List of other Filoviridae outbreaks
References
Events in Tanzania
March 2023 events in Tanzania
2023 in Tanzania
2023 disease outbreaks
Marburg virus outbreaks
Disease outbreaks in Tanzania
2023 disasters in Africa
April 2023 events in Tanzania
May 2023 events in Tanzania
June 2023 events in Tanzania | 2023 Tanzania Marburg virus disease outbreak | [
"Biology"
] | 465 | [
"Virus stubs",
"Viruses"
] |
73,590,797 | https://en.wikipedia.org/wiki/ClearVideo | ClearVideo was a video codec created by Iterated Systems Limited. It was one of the codecs available for the RealVideo container format. ClearVideo was marketed as a system that used fractal compression.
FFmpeg contains a decoder for a ClearVideo format, based on DCT encoding.
References
Video codecs | ClearVideo | [
"Technology"
] | 72 | [
"Computing stubs"
] |
73,590,840 | https://en.wikipedia.org/wiki/Invasomes | An invasome is a type of artificial vesicle nanocarrier that transport substances through the skin, the most superficial biological barrier. Vesicles are small particles surrounded by a lipid layer that can carry substances into and out of the cell. Artificial vesicles can be engineered to deliver drugs within the cell, with specific applications within transdermal drug delivery. However, the skin proves to be a barrier to effective penetration and delivery of drug therapies. Thus, invasomes are a new generation of vesicle with added structural components to assist with skin penetration.
Transdermal drug delivery
Transdermal drug delivery (TDD) systems aim to deliver drug therapies topically for local and systemic delivery. They have been gaining increasing attention within the field of drug delivery because of their potential to improve bioavailability, reduce side effects, and avoid first pass metabolism, compared to oral medications. However, TDD systems face the challenge of overcoming the barrier of the topmost skin layer, the stratum corneum.
Skin barrier
Transdermal drug delivery systems are methods to transport drug therapies across the skin barrier. The skin is the largest organ of the body and its primary aim is to protect the body against chemical, thermal, radiation, and microbial threats. However, it is not completely waterproof, allowing some exchange of gas, heat, and fluids from its external environment.
To effectively shield against external injuries, the skin is composed of several layers: the three distinguishing layers are the epidermis, the dermis, and the subcutaneous layer, or hypodermis. The bottommost layer is the hypodermis. It is primarily composed of adipose tissue. Next is the dermis, a 3-5 mm thick layer made up of fibrous proteins, an interfibrillar gel, salts, and water. The epidermis is the topmost layer of skin and where vascularization ends. Due to the lack of vascularization, the transfer of fluids, nutrients, and waste across the epidermis occurs through the epidermal-dermal junction. The epidermis is further divided into five layers. From innermost to outermost is the germinative stratum, the spinous stratum, the granular stratum, the lucid stratum, and the stratum corneum. The majority of the epidermis is composed of corneocytes, which develop from the proliferation, differentiation, and keratinization of keratinocytes. These fundamental skin cells continually renew as they move upwards toward the surface of the skin. The stratum corneum is a 10-15 μm thick layer of dead keratin-rich corneocytes tightly packed within a lipid-rich matrix, often described and depicted as a brick-and-mortar structure.
Penetration routes for transdermal drug delivery
Penetration of the stratum corneum is recognized as the largest challenge of TDD. Due to its tight cell structure, it is the rate limiting barrier for drug absorption. Thus, several methods of penetrating the stratum corneum have been explored. A couple of common methods include delivery through the intercellular route and the transcellular route. The roundabout, intercellular route seeks to bypass the corneocytes by transporting molecules through the lipid-rich intercellular space between the cells. The transcellular route seeks to transport molecules directly through the cells of the stratum corneum. In this method, molecules must travel through both corneocytes and the intercellular lipid space. The method of choice is dependent on physical and chemical properties of the transporting compounds; however, the intercellular route is the most common. Thus, the intercellular lipid barrier has been a subject of investigation to allow for greater understanding of how to develop transportation mechanisms of molecules through the stratum corneum.
Methods for increased transdermal penetration
In recent decades, due to the increasing use of therapeutic medications through transdermal pathways, techniques for improving permeation through the stratum corneum have been explored. The primary two routes of exploration have been chemical and physical penetration-enhancing mechanisms.
A brief overview of physical penetration methods are summarized in the table below.
Chemical characteristics to enhance drug delivery include incorporating salt formations, drug-ion pairs, eutectic mixtures, chemical penetration enhancers, and utilizing liposomal vesicles. Vesicles have shown the ability to be paired with current physical penetration techniques to synergistically improve drug penetration.
Invasome characteristics
Other vesicular systems, such as liposomes and ethosomes, have already been extensively researched and utilized as drug transporters, but the penetration barrier has resulted in studies to modify current vesicles to add characteristics for improved penetration of the stratum corneum.
Invasome vesicular systems are artificial vesicles composed of phospholipids, terpene, and ethanol. A phospholipid bilayer creates the external structure of the spherical particle. Within the bilayer are terpenes. Terpenes are naturally-occurring hydrocarbon chains that are commonly used in aromatics and scent products, but also have been used for the development of pharmaceuticals. Within the center of the terpene-and-phospholipid bilayer is a core that contains an aqueous hydroethanolic solution, along with the relevant drug.
Invasome penetration
Compared with other vesicular systems, the terpenes and ethanol function synergistically to increase the flexibility of invasomes, which allows for a softer, fluidic structure that increases penetration efficacy of the skin barrier.
Terpenes
Terpenes are known to be effective penetration enhancers. They function in invasomes by breaking apart the tight phospholipid structure of the stratum corneum, increasing the permeability of the intercellular space.
Ethanol
Like terpenes, ethanol has also been shown to disrupt the lipid structure of the stratum corneum, as well as loosening the invasome phospholipid bilayer. Ethanol also softens the lipids which increases the deformability of invasomes, allowing them to flatten to travel through the tight intercellular spaces of the skin.
Penetration mechanism
The terpenes and ethanol have been shown to loosen the invasome's phospholipid structure, allowing some of the terpenes and ethanolic solution to leak out of the invasome. There, they also separate the lipids of the stratum corneum. The smaller, flexible invasome is then able to travel intercellularly, passing through the stratum corneum to the viable cell layer where the drug is released and reaches systemic circulation. Thus, the terpenes and ethanol work in conjunction to both break up the phospholipids of the invasome they inhabit so they can pass through, as well as loosen the tight cellular matrix of the stratum corneum, giving the already-flexible invasomes an increased penetration ability.
Invasome preparation
Several preparation techniques of invasomes exist, but the most commonly used techniques are mechanical dispersion and thin-film hydration.
Mechanical dispersion
During lipid dispersion, the lipid and organic solvent are added with a drug of choice; then the solution is vortexed and sonicated for five minutes. PBS is added to the solution with additional vortexing, and then an aqueous buffer is used to hydrate the mixture. The spontaneous swelling of the lipids then creates the invasome vesicles, which are finally sonicated, lyophilized, and experience high-pressure extrusion.
Thin-film hydration
During thin-film hydration, also known as the conventional film method, lipids and drugs are added to ethanol and sonicated. A rotary flash evaporator is used to dry the mixture; nitrogen gas is used to remove harmful residual solvent. The resulting thin lipid films are hydrated using a PBS, and after cooling the terpene mixture is added to form the invasomes. Finally, the invasome solution is vortexed and ultrasonicated.
Applications
Pharmaceutical applications
Invasomes have been considered in a range of applications. Apart from cosmetics, they are increasingly becoming a part of pharmaceuticals and drug delivery research. Areas for use include delivery of immunosuppressive, anticancer, antiacne, contraceptive, erectile dysfunction, antihypertensive, alopecia, and antipsychotic drug therapies.
Drug delivery methods
Invasomes can be paired with transdermal delivery methods to target the skin barrier. Examples of these techniques include transdermal patches, microneedles, and creams.
Transdermal patches are medicated adhesives that can be applied to the skin. Compared to conventional hypodermic needles and oral delivery methods, patches allow for controlled release of drugs through the skin using built-in release mechanisms that allow drug reservoirs to discharge. Additionally, patches can be paired with microneedles to increase drug absorption.
Microneedles are minimally invasive arrays of needles that bypass the stratum corneum. They can range in length from a few micrometers up to 2000 μm, with the needles existing in several forms: solid, coated, dissolving, hollow, and hydrogel-forming.
Medical creams have been used for centuries due to their relative simplicity, ease of preparation, and ease of use. They are medically-treated, semi-solid formulations for topical drug delivery. Benefits of creams include increased patient compliance and avoidance of first pass metabolism.
References
Medical treatments
Routes of administration | Invasomes | [
"Chemistry"
] | 2,005 | [
"Pharmacology",
"Routes of administration"
] |
73,592,462 | https://en.wikipedia.org/wiki/Plectocarpon%20galapagoense | Plectocarpon galapagoense is a species of lichenicolous fungus in the family Lecanographaceae. Native to the Galápagos Islands, it grows on and within the ascomata and thallus of Sarcographa tricosa, a host lichen species. Although it appears to be a weak parasite, it may cause significant damage to the host lichen's reproductive structures.
Taxonomy
Plectocarpon galapagoense was described by Damien Ertz and Frank Bungartz in 2019. Its species epithet refers to its occurrence in the Galápagos Islands. The holotype specimen was collected by the second author on Pinta Island at an elevation of ; it was found in a forest of Zanthoxylum fagara with abundant ferns in the understory.
Description
The lichenicolous fungus initially grows immersed within the host lichen, eventually bursting through and appearing as black, star-shaped or rounded structures measuring 1–2 mm in diameter. The surface of the fungus is to , with a slit-like hymenial . It does not induce galls or produce necrotic areas on the host lichen.
Its asci are somewhat cylindrical to narrowly , with a narrow ocular chamber, and contain 4–8 spores. The are fusiform and contain two or three septa, initially hyaline but becoming dark brown and as they mature.
Similar species
While similar to Plectocarpon macaronesiae, P. galapagoense differs in the size of its ascomata, the appearance of its surface, and its host genus. Plectocarpon dirinariae is another similar species but differs in its ascomatal shape and host genus. Plectocarpon aequatoriale, found in Ecuador, has distinctly convex ascomata, longer ascospores, and a different host genus. Opegrapha plectocarpoidea, known from Papua New Guinea, differs in its ascomatal shape, number of spores in its asci, and the that continues below the hymenium.
Habitat and distribution
Plectocarpon galapagoense is endemic to the Galapagos Islands. It grows on Sarcographa tricosa sensu lato, which is found on twigs and branches of Chiococca alba trees in the forest understory of Zanthoxylum fagara on Pinta Island.
References
Lecanographaceae
Lichenicolous fungi
Fungi described in 2019
Fungi of the Galápagos Islands
Taxa named by Frank Bungartz
Fungus species
Taxa named by Damien Ertz | Plectocarpon galapagoense | [
"Biology"
] | 538 | [
"Fungi",
"Fungus species"
] |
73,592,636 | https://en.wikipedia.org/wiki/Anammox%20for%20wastewater%20treatment | Anammox is a wastewater treatment technique that removes nitrogen using anaerobic ammonium oxidation (anammox). This process is performed by anammox bacteria which are autotrophic, meaning they do not need organic carbon for their metabolism to function. Instead, the metabolism of anammox bacteria convert ammonium and nitrite into dinitrogen gas. Anammox bacteria are a wastewater treatment technique and wastewater treatment facilities are in the process of implementing anammox-based technologies to further enhance ammonia and nitrogen removal.
Morphology and physiology
Anammox bacteria can be found in wastewater treatment plants, lakes, suboxic zones, and coastal sediments. Anammox bacteria are temperature-dependent, requiring temperatures between 30˚C to 40˚C to grow. Anammox bacteria growth is also impacted by pH, growing best at pH ranges of 6.5 to 8.3. Anammox bacteria are made up of an anammoxosome membrane, which takes up 50% to 70% of the cell volume, and a cell membrane surrounded by ladderane lipids.
Chemical process
The two main chemicals needed for the metabolism of anammox bacteria to function are ammonia and nitrite. Nitrate and nitrite are produced by microorganisms within wastewater treatment facilities as a result of sewage treatment. The chemical compound ammonia monooxygenase converts ammonia in wastewater into nitrite during the nitrification process.
Anaerobic ammonium oxidation bacteria (Anammox) reactions, are mediated by the chemoautotrophic bacteria that are from the phylum Planctomycetota. Anammoxosome is the compartment within anammox bacteria where anammox reactions occur. During this process, a proton gradient is produced across the anammoxosome membrane, starting a catabolic reaction. Nitrate is first converted to nitric oxide in the presence of nitrate reductase, which is the first step in this reaction. Anammox oxidizes ammonium into nitrite, which is the reduced to hydroxylamine. Hydroxylamine and ammonia then react to form hydrazine, which is then oxidized into nitrogen gas.
Chemical reaction for anammox, conversion of ammonia to nitrogen gas
Impacts on wastewater treatment
Wastewater usually exists in a mix of solid and liquid forms. The composition of wastewater varies depending on how it has been generated. "Wastewater" may refer to domestic wastewater, wastewater from industry, or surface water runoff. Treatment of wastewater to improve sanitation is a major challenge in developing countries, as untreated wastewater can contaminate drinking water.
Anammox bacteria treatments have been implemented in treatment facilities to help convert sewage wastewater into sludge ash, which is then used as a fertilizer source for agriculture. Sludge ash can be used as fertilizer due to its rich concentration of phosphorus and other nutrients necessary for plant growth. The crystallization of struvite (made up of magnesium, ammonium, and phosphate) during the wastewater treatment process can also be used as a fertilizer. The addition of magnesium to wastewater that already contains ammonium and phosphate allows for a 1:1:1 mole ratio in which all three elements bind to one another, allowing struvite to form as a product according to figure 1. The struvite crystals contain nutrients essential to plant growth that are easy to use and transport. This process also helps to recover nitrogen and phosphorus from wastewater, helping to improve surface water quality as these are two of the primary elements that can cause eutrophication. If eutrophication occurs, an anammox cycle can take place in the absence of oxygen and with high nitrite and ammonia concentrations. These two compounds are needed for the anammox cycle to begin, and are present in wastewater in high concentrations. The anammox bacteria present can help clean up wastewater of excess nitrite and ammonia.
References
Anaerobic digestion
Environmental microbiology | Anammox for wastewater treatment | [
"Chemistry",
"Engineering",
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73,595,058 | https://en.wikipedia.org/wiki/Cervical%20drug%20delivery | Cervical drug delivery is a route of carrying drugs into the body through the vagina and cervix. This is a form of localized drug delivery that prevents the drugs from impacting unintended areas of the body, which can lower side effects of toxic drugs such as chemotherapeutics. Cervical drug delivery has specific applications for a variety of female health issues: treatment of cervical cancer, pregnancy prevention, STD prevention, and STD treatment.
Biological considerations
Cervical mucus
Viscous mucus secreted by glands in the cervix presents a unique environment for drug delivery. Due to its ability to retain substances and slowly release them, it holds potential to be used as a natural, noninvasive drug delivery system. The mucus can act as a reservoir for compounds that destroy pathogens. However, the cervical mucus also presents a barrier to drug delivery as it can be really thick, making it difficult to permeate the mucus barrier. The mechanisms for penetration and bioactivity of the cervical mucus must be understood to utilize the mucus’s potential as a drug delivery system. Due to the changes in viscosity and water content of the mucus during the stages of the menstrual cycle, this poses a particularly complex consideration. For example, the cervical mucus will be thicker when a woman is not ovulating in order to prevent sperm from being able to penetrate the mucus barrier, which also in turn makes in more difficult for penetration of drug delivery systems.
Vaginal pH levels
The vaginal environment is slightly acidic, with pH ranging from 3.8 - 4.5 based on multiple factors such as age, natural bacteria, and stage of menstrual cycle. Due to the variety in possible pH values, this poses an interesting consideration for drug delivery. Absorption and release of drugs is often influenced by pH, so if the pH is changing through the menstrual cycle, different combinations could be needed at different times to achieve the most effective drug delivery system.
Applications
Birth control
Some hormonal birth control methods utilize cervical drug delivery methods. The earliest example of such dates to 1850 Ancient Egypt when acadia gum was inserted into the vagina, releasing spermicidal components. Examples in the modern era include vaginal rings and intrauterine devices (IUDs) that release hormones into the reproductive system to prevent fertilization. Vaginal rings are plastic ring-shaped devices that are inserted into the vaginal canal and slowly release hormones such as estradiol or progestin. Hormonal IUDs are T-shaped devices inserted into the uterus, releasing progestin over extended periods of time. These hormones work to thicken the cervical mucus to prevent sperm from penetrating and reaching the fallopian tubes. Copper IUDs are another form of intrauterine devices that release copper ions instead of hormones. The copper ions are toxic to sperm and therefore prevents successful fertilization.
Cervical cancer treatment
The most common application of cervical drug delivery is for treatment of cervical cancer. Due to the direct route provided through the use of cervical drug delivery mechanisms, it proves to be the most effective route with the lowest number of side effects. The localized treatment has been suggested as ideal as cancer is treated with highly toxic compounds, such as chemotherapeutics. The more contained the exposure to these compounds can be, the less negative impacts the patient will endure. Treatment can be delivered in the form of nanoparticles, vaginal gels, or films and reach the cervix quickly for ideal response. Vaginal gels are easily administered into the vaginal canal to reach the cervix due to low viscosity at room temperature. When inserted into the body which has a higher temperature, the gels become more viscous, allowing them to reside longer at the cervix and have more sustained release. Vaginal films are very thin films inserted into the vagina to release a compound. They can be maintained for six hours in cervical mucus, meaning they hold potential to treat cervical cancer caused by Human Papilloma Virus. Nanoparticle systems take advantage of the size of nanoparticles to encapsulate the drugs and pass through the mucus barrier.
Sexually transmitted diseases
Cervical drug delivery serves as a route for compounds to prevent and treat sexually transmitted diseases (STDs). Prevention of STDs for women can be achieved by administering preventative compounds into the vaginal canal prior to intercourse. One method researched is the use of a CAP technology that remains stable in the vaginal environment, but breaks down in the presence of human semen, releasing a drug to destroy STDs. This application of cervical drug delivery would be useful for prevention of STDs in women without interfering with the bodily environment until there is potential for infection. STDs can also be treated through cervical drug delivery methods. Antibiotics for STD treatment are often administered into the vagina in the form of creams or gels.
Fertility treatment
Hormones to increase fertility are also often delivered through the cervical route. While this is less common than applications for birth control, it essentially utilizes the same concepts. Hormones influence the natural menstrual cycle, so instead of using hormones that prevent ovulation, hormones are used to encourage ovulation, such as follicle-stimulation hormones (FSH) and luteinizing hormones (LH). Fertility lubricants are the most common example of fertility treatments delivered through the cervical route. These lubricants are designed to mimic a pH and viscosity that is conducive for sperm to reach the fallopian tube. Studies are being done to combine the properties of fertility lubricants with fertility increasing hormones to lead to more direct and efficient treatment.
Current products
Vaginal rings
Vaginal rings are most commonly used for birth control purposes but can also be used to release compounds that treat and prevent STDs as well. The rings come in one standard size that fits most women and are made of flexible materials that contain the desired compound, whether that be hormones for birth control or other compounds for STD treatment. These substances are then slowly released over an extended period of time, typically a month. This is a convenient drug delivery method because they can easily be inserted and removed and do not prohibit intercourse. For birth control purposes, the vaginal ring is removed after 3 week and a new one is inserted a week later. Vaginal rings are also often used to treat symptoms of menopause, and these rings are replaced after a 3 month use. STD prevention and treatment through the use of vaginal rings is a newer application of such a device, but holds an advantage as a low maintenance option for women in areas with less access to regular healthcare.
Suppositories
Vaginal suppositories are forms of medications that are inserted into the vagina in a solid form, but melt from body heat to release the substances. Common uses for them are to treat yeast or bacterial infections. Hormones are often delivered in this form for treatment of menopausal or menstrual related issues. Spermicide can also be delivered as a suppository when inserted prior to intercourse for birth control purposes. Insertion of vaginal suppositories uses a mechanism and applicator similar to that of a tampon. If there is no applicator available, they can be inserted with two fingers pushing them into the vaginal canal as far as is comfortable.
Vaginal gels
Vaginal gels are forms of medication that are water-based. They are applied using a plastic applicator to distribute the gel throughout the length of the vaginal canal. These gels tend to have release kinetics that are fast acting, which makes them useful for treatment of irritations. Antibiotics are often distributed in the form of a gel for treatment of common infections, including sexually transmitted infections (STIs). The gels also have the benefit of being lubricating, which grants additional relief to symptoms of dryness and itching that is common with vaginal infections. Gels that are in the form of liposomal structure have been shown to retain substances for extensive periods of time, making them useful for slow release of drugs administered through the cervical drug delivery route
New technologies
Vaginal films
Vaginal films are soluble, thin sheets of medication that are inserted into the vagina where they dissolve and release the substances. Typical uses include delivery of contraceptive substances or antibiotics for infections. These films are inserted by simply pushing them into the vagina with one’s fingers. There they dissolve quickly upon interaction with natural vaginal fluids.
Bioadhesives
Bioadhesives are substances that naturally stick to live tissue. Currently, studies are being done on bioadhesives adhering to cervical mucous membranes to allow for an extended release period. The drug would be released with mucus to create a localized treatment with high effectiveness. This is anticipated to be highly useful for treatment of cervical cancer. Bioadhesives can come in multiple forms, such as films, tablets, or gels. The appeal of bioadhesives is that they take advantage of the mucous environment surrounding the cervix and utilize it to benefit the drug delivery mechanism.
References
Drug delivery devices
Cervical cancer | Cervical drug delivery | [
"Chemistry"
] | 1,894 | [
"Pharmacology",
"Drug delivery devices"
] |
73,595,951 | https://en.wikipedia.org/wiki/Artificial%20white%20blood%20cells | Artificial white blood cells are typically membrane bound vesicles designed to mimic the immunomodulatory behavior of naturally produced leukocytes. While extensive research has been done with regards to artificial red blood cells and platelets for use in emergency blood transfusions, research into artificial white blood cells has been focused on increasing the immunogenic response within a host to treat cancer or deliver drugs in a more favorable fashion. While certain limitations have prevented leukocyte mimicking particles from becoming widely used and FDA approved, more research is being allocated to this area of synthetic blood which has the potential for producing a new form of treatment for cancer and other diseases.
Leukocyte Physiology
Leukocytes, otherwise known as white blood cells (WBCs), come in various types and generally circulate around the body to facilitate warding off pathogenic invaders such as bacteria or viruses, as well as cells turned cancerous. They mainly circulate throughout the vasculature including capillary beds, bone marrow, and lymph vessels. The five major types of WBCs are neutrophils, eosinophils, basophils, monocytes, and lymphocytes. There exists leukocytes that do not circulate but instead remain in a particular tissue. These include histiocytes and dendritic cells. They typically range in size from 8 to 18 μm in diameter depending on cell type and stage in development. Leukocytes make up roughly 1% of the total blood cells in the average human body. Leukocytes maintain the expression of CD47 and CD45 biomarkers which indicate to other cells what they are and that they should not be destroyed. Cells like dendritic cells are involved in the innate immune system, whereas cells like lymphocytes are part of the active immune system.
Neutrophils
Through the mechanism of chemotaxis, neutrophils are typically found migrating toward sites of inflammation that are secreting heightened concentrations of inflammatory chemical signals. Once they arrived at the site of inflammation, they release cytokines to activate other types of leukocytes. The distinct chemotaxis behavior of neutrophils allows for localized targeting of cancer sites using manipulated neutrophils. Neutrophils are the first to fend off pathogens and achieve such through phagocytosis, degranulation, and extracellular traps.
Eosinophils
Eosinophils are weaker than neutrophils at performing phagocytosis and effectively diminishing infectious pathogen populations. However, they excel at targeting and eliminating certain parasitic organisms through release of granules containing toxic proteins, including RNAases which are effective against viruses.
Basophils
Primarily involved in allergic reactions, basophils release granules containing heparin, histamine, and proteolytic enzymes. They possess similar anti-parasitic properties to eosinophils, as well as exhibit regulatory functions of T-cells and control the degree to which other immune cells are activated.
Monocytes
Once monocytes enter the region containing pathogens, they differentiate into macrophages that eliminate certain pathogens through phagocytosis. They serve a key role in presenting antigens to T-cells which produce immune system alerting signals upon coming into contact with said antigens.
Lymphocytes
Lymphocytes can be further divided into three main types. These include B-cells, T-cells, and natural killer (NK) cells. B-cells become activated and produce antibodies to bind and tag unwanted antigens for destruction and digestion. Once activated, they immediately begin producing antibodies for urgent action, or they circulate around the body as memory B cells to serve as protection against a particular antigen for long periods of time. T-cells have several key functions, including activation of other cells such as B-cells, helper T-cells and CD4+ cells, as well as elimination of virally infected cells and cancer cells. NK cells are involved in the innate immune system, and they kill pathogens via release of perforin and granzyme to directly destroy cell membranes, release of cytokines such as TNF-α to boost activity of other WBCs, as well as secretion of signals that trigger apoptosis. NK cells also can act to destroy pathogens without prior stimulation, unlike T-Cells.
History
Research into artificial WBCs began around the time as artificial red blood cells as an effort to address the lack of whole blood donations available for emergencies. The artificial WBCs developed since the 2000s have less to do with reproducing exact replicas of immune cells with their every feature, and more to do with creating simple vesicle-like particles the size of actual immune cells that are capable of performing tasks and mimicking the physiological features of biological immune cells to an efficacious degree. The main mechanisms in particular that are commonly mimicked in artificial WBCs are the release of cytotoxic compounds and ability to perform phagocytosis.
Current Advancements
Leukosomes
Leukosomes are lipid bilayer vesicles with embedded proteins that are found in the membranes of naturally produced leukocytes. Leukosome particles exhibit similar mechanical and physiological qualities to leukocytes while also benefiting from the advantages of liposomal manufacturing and therapeutic administration. Leukosomes were shown to preferentially target inflamed endothelial tissue both in vitro and in vivo. They are typically manufactured by harvesting immune cells from an organism, most often mice, and disposing of all native components except the plasma membrane. Once the plasma membrane is isolated, it is enriched with proteins to give the particle a similar composition to the desired subject's leukocytes, and loaded with therapeutic membrane soluble compounds such as glucocorticoids that exhibit anti-inflammatory qualities. When loaded with dexamethasone, the leukosomes were able to accumulate in sites of inflammation and reduce expression of pro-inflammatory markers. Other studies found that leukosomes decrease expression of pro-inflammatory genes while increasing expression of anti-inflammatory genes, exhibiting promise as a treatment method for inflammatory diseases. In one study, leukosomes loaded with doxorubicin injected into murine models inhibited breast and melanoma tumor growth more effectively than dissolved circulating doxorubicin. Another study examined the differences in therapeutic behavior between liposomes and leukosomes both loaded with doxorubicin and found that unlike liposomes the loaded leukosomes better incorporated themselves into surrounding cells in vitro and served as an effective drug depot for the doxorubicin.
Leukopolymersomes
Luekopolymersomes are polymer block-based nanoparticles that excel at mimicking the adhesive qualities of leukocytes, specifically the binding of selectins and integrins found in native leukocytes. Polymersomes are typically made of biodegradable polymers such as poly(lactide), PCL, PTMC, poly(L-glutamic acid) and dextran. Unlike lipid nanoparticles which can only take on a spherical shape, polymersomes can be formed into various shapes such as discs, ellipsoids, and tubes. Methods such as thin film rehydration and direct injection result in polymersomes of variable sizes. Others such as polymerization induced self-assembly and flash nanoprecipitation are more consistent manufacturing methods with regards to size. These particles are more stable than phospholipid vesicles, featuring higher levels of strain before breakdown. This is particularly useful as it allows for adhesion at sites of inflammation where there are considerable shear forces. The thicker membranes and arrangement of hydrophobic chains of polymersomes greater stability and drug retention within the body. The surface of polymersomes is compatible with both covalent and non-covalent conjugation chemistry which can be used to target specific tissues and cellular surfaces. An early study from 2003 developed a method for producing "PLGA microspheres" that can be loaded with anti-inflammatory drugs, adhere to sites of inflammation, and release the loaded drug via selectin and ligand chemistry. These in concept are early versions of polymersomes. Polymersomes can mimic antigen presenting cells when loaded with tumor antigens to elicit a stronger immunogenic response, effectively acting as nanovaccines. Leukopolymersomes have the potential to be used as treatment for inflammation and cancer.
Leukolike Vectors
Leukolike vectors are a type of nanoparticles made of nanoporous silicon encapsulated by extracted native leukocyte membranes. These particles were among the first artificial white blood cells to be studied as a proof of concept of using cellular membranes to prolong circulation of nanoparticles throughout the blood. Studies have shown that leukolike vectors have a specific advantage in chemotherapy drug delivery to cancer. This is because leukolike vectors specifically have the potential to bind to tumor endothelium.
Nanoghosts
Nanoghosts are nanosized vesicles containing a chosen drug delivery payload manufactured from extracted leukocyte membranes with the cell cytoplasm content removed. The use of biological membranes serves to mask the particles from the immune system to reduce the likelihood of an immunogenic response, as well as to extend circulation of the particles in the blood. They are produced by homogenizing the cells to remove the cytosol, and then sonicating the empty cell membranes to create nanoghosts between 100 and 200 nm in diameter. Membranes used to make nanoghosts harvested form red blood cells have been shown to circulate for about 120 days and avoid phagocytotic cells. Neutrophil based nanoghosts retain the chemotaxis capacity of neutrophils to sites of inflammation, which encourages tumor targeting. NK based nanoghosts exhibit metastatic cancer targeting behavior. Monocyte based nanoghosts are effective at infiltrating the tumor microenvironment. Mesenchymal stem cell derived nanoghosts exhibit cancer targeting properties.
Artificial Antigen Presenting Cells
Artificial Antigen Presenting Cells (aAPCs) are polystyrene beads with stimulating receptor ligands. aAPCs loaded with cytokines have been found to stimulate T-cells to a higher degree than particles containing solely costimulatory ligands.
Limitations
The major limitation in the development of artificial WBCs is the translation of the technologies into clinical approval and use. Other limitations include the availability of technology necessary to produce artificial WBCs, variability in yield, and difficulties in purifying the particles necessary for standard clinical use. Some studies have also found that these particles may unintentionally target other tissues that are otherwise healthy. The delivery of the therapies faces some difficulties in that too rapid administration might cause systemic side effects, whereas a too slow release would be less effective. A major limitation to polymersomes is that a select number of polymers such as polyethylene glycol and poly(lactic-co-glycolic acid) are approved by the FDA for clinical use. Nanoghosts, or more generally membrane-coated nanoparticles, experience limitations in that cells will have varying degrees of proteins present in their membranes, creating variability and lack of stability in those products. There also is the risk that membrane proteins essential to the biomimetic function of the nanoghosts can become denatured in the manufacturing and storage process. Overall, more studies need to be done on these biomimetic solutions to verify efficacy and safety.
References
Blood cells
Blood substitutes
Synthetic biology | Artificial white blood cells | [
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"Biology"
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73,596,283 | https://en.wikipedia.org/wiki/Zeolite%20membrane | A zeolite membrane is a synthetic membrane made of crystalline aluminosilicate materials, typically aluminum, silicon, and oxygen with positive counterions such as Na+ and Ca2+ within the structure. Zeolite membranes serve as a low energy separation method. They have recently drawn interest due to their high chemical and thermal stability, and their high selectivity. Currently zeolites have seen applications in gas separation, membrane reactors, water desalination, and solid state batteries. Currently zeolite membranes have yet to be widely implemented commercially due to key issues including low flux, high cost of production, and defects in the crystal structure.
Production methods
There are several methods used for the formation of Zeolite membranes.
The In Situ method involves Zeolite membranes being formed on microporous supports of various materials, typically aluminum oxide or stainless steel. These supports are then immersed in a solution of Aluminum and Silicon at a specific stoichiometric ratio. Other factors of this solution can affect the formation of the zeolite membrane including: pH, Ionic Strength, temperature, and the addition of structure-determining reagents . Upon heating the solution, the crystals of the membrane begin to grow on the supports.
In 2012, a “seeding method” was developed to produce zeolite membranes. In this case, the support is seeded with preformed zeolite crystals, before immersing it in the solution. These crystals allow for the formation of thinner membranes that typically contain fewer defects by growing the membranes off of existing structures.
Properties
Zeolite membranes drew initial interest as a separation method due to their high thermal and chemical stabilities. The crystal structure of zeolite membranes also creates a uniform pore size of approximately .3-1.3 nm in diameter. The crystal structure of zeolites also leads to the presence of several defects, which can often create gaps in the structure larger than these pores. The presence of defects can make these membranes far less effective, and it is difficult to produce defect free zeolite membranes.
There are several mechanisms of transport that govern the separation of molecules by zeolite membranes. The main mechanisms for separation by zeolite membranes are molecular sieving, diffusion, and adsorption. Molecular sieving involves the rejection of any molecules of a size greater than the pore size of the membrane. This is a relatively simple sieving process which can separate out very large molecules. Adsorption involves molecules passing through the pores of the membrane being adsorbed onto the membrane surface. Adsorption properties of the membranes can be changed by adjusting various structural properties of the membrane.
Surface diffusion is a process in which molecules adsorb to the pore wall of the membrane, and are slowly transported through the pores. During surface diffusion, molecules that are adsorbed at a higher rate can begin to block the membrane pores from other, less adsorbed, molecules. Surface diffusion can account for the high selectivity of certain molecules such as hydrogen by zeolite membranes. Surface diffusion typically plays a larger role in the transport of molecules at lower temperatures.
Knudsen diffusion also contributes to the varying selectivity of zeolite membranes towards different molecules. Knudsen diffusion takes place when molecules are momentarily adsorbed to the pore wall and are then reflected off the surface in a random direction. This random motion allows for separation of molecules based on their velocities. Graham's law for diffusion dictates that lighter molecules will have a higher average velocity than heavier molecules, thus resulting in an increased flux with respect to lighter molecules. These differences in flux can be used to separate different molecules using zeolite membranes.
Applications
Gas separation
Zeolite membranes have seen the most promise in regards to gas separation applications. The ability of zeolite membranes to adsorb certain molecules to its surface under varying conditions allows for researchers to perform highly selective separations. Adsorbed molecules block diffusion pores, and prevent the diffusion of other molecules through these pores. Zeolites typically adsorb carbon dioxide at the highest rate, lending themselves to use in carbon dioxide capture and separation. Diffusion selectivity governs the separation of molecules in zeolite membranes at higher temperatures. Diffusion selectivity allows for the quicker diffusion of smaller molecules through the membrane and slower diffusion of large molecules through the membrane's pores.
The natural gas industry has seen the introduction of zeolite membranes for the separation of methane, carbon dioxide, and hydrogen gasses. Zeolites provide the advantage of thermal stability and higher selectivity when compared to polymer membranes that have typically been used for these purposes. There still needs to be improvement in the production of zeolite membranes, particularly regarding the cost, before they see widespread use.
Membrane reactors
Zeolite membranes have also been used in membrane reactors, since their chemical and thermal stabilities allow them to withstand reaction conditions. Membrane reactors function by removing the product of a reaction as the reaction occurs. This removal shifts the equilibrium of the reaction to allow for the formation of more products, as outlined by Le Chatelier's principle creating a more efficient reaction process. The high selectivity of zeolite membranes allows for them to be used to remove products from a reactor at high rates.
Water desalination
Zeolite membranes have recently been studied as an alternative for energy efficient water desalination. Currently water desalination is primarily done by Reverse Osmosis filtration which uses a dense polymeric membrane to purify the water. Zeolite membranes have been tested as an alternative water purification method, and are able to separate water from impurities. Zeolites have not been implemented for industrial water desalination purposes primarily due to their high cost when compared to traditional reverse osmosis membranes.
References
Membrane technology
Filtration
Zeolites | Zeolite membrane | [
"Chemistry"
] | 1,192 | [
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73,596,817 | https://en.wikipedia.org/wiki/Breast%20milk-mediated%20drug%20delivery | Breast milk-mediated drug delivery refers to the use of breast milk to transport a pharmaceutical compound, protein, or other treatment to achieve a desired effect. Delivery of these substances via milk provides an oral alternative for transport of a compound to the gut, specifically in infants. Breast milk-mediated drug delivery provides a way for pharmaceuticals and proteins to travel through the gastrointestinal system of an infant while minimizing the potential for irritation within gastrointestinal tissue.
Addition of compounds into breast milk
There are multiple routes that a treatment can enter into the breast milk. One route is through a breastfeeding mother. When a mother that is lactating receives a treatment including but not limited to prescription medication, over-the-counter medications, or herbal remedies, these compounds can make their way into the mother’s milk and are subsequently delivered to an infant via breastfeeding. The amount of treatment transferred into the milk depends on the substance, but it is noted that these compounds can have an effect on the infant consuming the breast milk.
A common method for intended addition of treatment into breast milk involves the use of donor breast milk in combination with the compound of interest for treatment. Addition of antibiotics, oligosaccharides, cytokines, or selected proteins into donor breast milk for consumption can have a variety of effects on the patient consuming it, typically an infant. This method has also been studied for use in adults, specifically for the delivery of poorly water-soluble drugs. While this method allows for the highest level of modularity among breast milk treatments, the effects of these treatments on various factors such as the microbiome of the milk base must be acknowledged to limit potential side effects.
Other novel technologies for drug delivery via breast milk involve the use of external objects to mediate the addition of compounds into the milk being consumed. One of these technologies is a nipple shield. A nipple shield is placed onto the nipple of a breastfeeding mother, releasing treatment into the milk as the mother breastfeeds an infant. Many of these novel technologies still require testing for efficacy and safety before any potential commercial application.
Potential applications
Breast milk fortification
Breast milk fortification refers to the addition of nutrients such as proteins, oligosaccharides, or cytokines into breast milk to supplement the natural contents of the milk. This practice is common in babies that have been born prematurely, with a major goal of this practice being growth promotion. These infants do not receive enough nutrients for proper growth and development from a normal breastfeeding regimen, potentially leading to neural and/or cognitive impairment. Thus, supplementation of breast milk with proteins, calcium, phosphate, and other nutrients can help to remedy this issue.
Studies have shown that human milk fortification can improve the short-term growth of infants, though future research is needed to determine long term growth effects. There is variation with results from case to case, however. The nonstandard concentration of proteins across different mothers’ breast milk can lead to issues when pinpointing the amount of nutrients an infant is receiving. While there is a standard fortification level used in most cases, “Adjustable Fortification and “Targeted Fortification” are being researched as ways to provide targeted individual fortification to suit the needs of each individual being treated.
One particular compound that can be used to fortify breast milk is Human Milk Oligosaccharide. These prebiotics are found naturally in human breast milk, and provide a variety of health benefits to newborns, including modulation of the immune system, fighting viral infections, and promoting epithelial cell maturation. These prebiotics, which have been confirmed to be safe and tolerable for infants, are a leading candidate for breast milk fortification.
Antibiotic addition
Antibiotics can be added into breast milk as a preventative measure for the development of infections such as Subsequent Late Onset Sepsis and Necrotizing Enterocolitis. Antibiotic treatment is a very common treatment for premature babies, though dosing regimen and treatment length tend to be “arbitrary”. While potentially detrimental to the health of the gut microbiome if given in excess, the administration of antibiotics within breast milk can help to prevent infection in newborns.
Antibiotics are used as the most common treatment for prematurely born infants in Neonatal Intensive Care Units – used as a preventative measure for infection. These treatments usually contain empirical antibiotics and are often given to infants that do not show signs of bacterial infection. Studies are currently being performed to determine the optimal length of treatment for infants to prevent infection while maintaining gut health, specifically in the microbiome.
Stability of milk-drug formulations is another factor that contributes to the effectiveness of antibiotic addition into breast milk. Many orally delivered antibiotics show poor solubility in aqueous environments, leading to increased research into lipid-based drug delivery systems. Milk formulations, which contain varying levels of natural lipids, have been shown to increase delivery efficacy of antibiotic compounds, while maintaining stability and integrity of the colloidal structure that makes up milk.
Prevention of necrotizing enterocolitis
Addition of carefully selected compounds into breast milk have been shown to not only stimulate growth within an infant, but also help to prevent infections from forming, specifically in the gut. Babies born very prematurely are at high risk for these infections, particularly necrotizing enterocolitis. Necrotizing enterocolitis is an intestinal condition that develops in some premature babies, and is characterized by inflammation, bacterial infection, potential intestinal injury, and in extreme cases, death.
The development of necrotizing enterocolitis has also been linked to the microbiome of the gut in the affected population. High levels of antibiotic administration have been shown to reduce the variety of bacteria present within the gut microbiome, and this lower level of diversity found in these infants can increase their susceptibility to necrotizing enterocolitis. Studies have indicated that time of administration of antibiotics as well as type of antibiotic can impact the incidence of the condition.
Prevention of necrotizing enterocolitis in premature infants is mainly achieved through the addition of predetermined compounds into donor breast milk that is fed to premature infants at risk for the condition. Compounds such as immunoglobulins have been shown to reduce Necrotizing Enterocolitis incidence, as well as severity in those that still develop the condition. Studies have shown that the addition of IgA and IgG into a premature infant’s feed can lower the incidence of the disease in the population of infants that are at the highest risk for the condition (very premature, low birth weight).
Problems
One of the main issues surrounding breast milk-mediated drug delivery is the uncertainty of the composition of the milk acting as the vessel for the treatment. Since every breastfeeding mother experiences different external conditions such as diet and environment, as well as differences in genetics, breast milk from every mother will have a different composition, making it difficult to create replicable treatments from infant to infant. Donor breast milk encounters this same issue, with infant formula acting as a potential avenue for stabilization of treatment levels.
Improper administration of antibiotics into an infant’s gastrointestinal system can increase the susceptibility of infants to gut infections. This is due to the lowered diversity and viability of organisms found within the gut, also known as the microbiome. Especially prevalent in preterm infants, this deviation from a healthy microbiome can lead to adverse effects during the beginning of an infant’s life. These infants may be predisposed to conditions such as Necrotizing Enterocolitis due to higher growth of pathogenic bacteria within the gut, as well as a lower count of commensal bacteria growth.
Future prospects
New breast milk-mediated therapies are still in development, aiming to take advantage of properties that are unique to this form of treatment. One such technology is the use of exosomes found in milk to transport molecules such as mRNA, DNA, and proteins to an area of interest. This research proposes the use of milk, as a scalable source of exosomes for a method of targeted drug delivery with higher efficacy than standard oral methods. These novel therapies may provide a way to achieve a low-cost method to deliver drugs with poor water solubility into the body, with potential use as a low-cost alternative.
See also
Breast Milk
Breastfeeding and Medications
Human Milk Bank
Drug Delivery
Food Fortification
Necrotizing Enterocolitis
References
Drug delivery devices | Breast milk-mediated drug delivery | [
"Chemistry"
] | 1,732 | [
"Pharmacology",
"Drug delivery devices"
] |
73,597,668 | https://en.wikipedia.org/wiki/State%20of%20Happiness | State of Happiness () is a Norwegian period drama television series about the discovery of oil in the North Sea, and subsequent growth of the petroleum industry in Stavanger, beginning in 1969. It is directed by Petter Næss and Pål Jackman, written by Mette Marit Bølstad and coproduced by NRK and Maipo Film. Its first season premiered on NRK1 in 2018, and is set during the years 1969 to 1972. Its second season, covering the years 1977 to 1980, premiered in 2022. A third season, covering the years 1987 to 1990, was ordered in October 2022, with filming commencing in March 2023 and Norwegian premiere on 29 October 2024.
The series has drawn comparisons to the American period drama Mad Men.
Cast and characters
Anne Regine Ellingsæter as Anna Hellevik, a secretary and Christian's fiancée
Amund Harboe as Christian Nyman (season 1), an oil rig diver and Anna's fiancé
Paal Herman Ims as Christian Nyman (seasons 2 & 3)
Bart Edwards as Jonathan Kay, a lawyer from Phillips Petroleum Company (seasons 1 & 2)
Malene Wadel as Toril Torstensen, a young mother and worker at Fredrik Nyman's company
Pia Tjelta as Ingrid Nyman, a socialite, wife of Fredrik, and mother of Christian
Per Kjerstad as Fredrik Nyman, owner of a fish canning company in Stavanger, husband of Ingrid, and father of Christian
Mads Sjøgård Pettersen as Martin Lekanger, an oil rig diver
Adam Fergus as Ed Young, a businessman from Phillips Petroleum Company
Ole Christoffer Ertvaag as Rein Hellevik, Anna's brother
Laila Goody as Randi Torstensen, Toril's mother, and a devout Christian
Vegar Hoel as Arne Rettedal, a Stavanger politician
Roar Kjølv Jenssen as Leif Larsen, the mayor of Stavanger
Peter Førde, as Bjørklund, a deep sea diver (season 3)
Awards and accolades
The first season of the series received five Gullruten awards from among eight nominations in 2019, including best drama series and best actor (Anne Regine Ellingsæter). Its second season received another nine nominations, winning five Gullruten awards in 2022.
Internationally, the series won awards for best screenplay and best music at the inaugural Canneseries in 2018. It received nominations in three categories during the 2019 Monte-Carlo Television Festival, but did not win.
International release
Internationally, broadcasters in more than 60 countries have bought rights to the series, according to NRK. The series is known by the title "State of Happiness" in English. In the UK, the series was acquired by BBC Four. It was also acquired for Topic's streaming platform in the United States.
Reception
The Times Carol Midgley said that the series,"has a hypnotic charm and easily stands on its own merit", giving it four out of five stars.
References
External links
Television shows set in Norway
Television series set in the 1970s
Norwegian drama television series
2018 Norwegian television series debuts
Works about petroleum | State of Happiness | [
"Chemistry"
] | 659 | [
"Petroleum",
"Works about petroleum"
] |
73,598,113 | https://en.wikipedia.org/wiki/Savoryella%20lignicola | Savoryella lignicola is a species of marine and freshwater based fungi in the Savoryellaceae family of the order Savoryellales. They are saprobic (processing of decayed (dead or waste) organic matter) on submerged wood.
Taxonomy
The genus name of Savoryella is derived from John George Savory (1917-2003), who was a mycologist, born in Sacriston, Co Durham, England. In 1969, a completely new genus of fungi was discovered by researchers at Portsmouth Polytechnic to cause soft rot in the marine environment, its identifier, botanist Evan Benjamin Gareth Jones, gave the new genus of fungi, the name of Savoryella in tribute to Savory.
The Latin epithet "lignicola" means "living on wood".
Taxonomically, Savoryella had been referred to several orders (Jones et al. 2016). In 2011, Savoryella together with genus Ascotaiwania, Canalisporium (and its sexual morph Ascothailandia) formed a distinct clade in the Hypocreomycetidae subclass (within the Sordariomycetes class), based on phylogenetic analyses of the SSU and LSU rRNA, RPB2, and TEF-1-alpha genes (Boonyuen et al. 2011). It can also occur early in the colonization of timber test panels and also on well-decayed wood (Eaton & Jones 1971), and also causes active soft-rot decay of wood (Mouzouras 1986).
History
Savoryella lignicola was initially described from test panels of Fagus sylvestris and Pinus sylvestris, exposed in a water cooling tower run with brackish water (Eaton & Jones 1971), at Connah's Quay in Wales.
It was later reported as a cosmopolitan species (Jones and Eaton, 1969; Ho et al., 1997; Jones et al., 2016). This is the sole Savoryella taxon detailed from both marine and freshwater environments (Ho et al., 1997; Luo et al., 2004). Though the marine and freshwater isolates of Savoryella lignicola are morphologically alike, it is doubtful whether they are same species (Ho et al., 1997). Molecular data are available only for two Savoryella lignicola strains described from mangrove wood from Malaysia and submerged Nypa fruticans fronds from Thailand, with no molecular data for the freshwater strain of Savoryella lignicola (Ho et al., 1997; Boonyuen et al., 2011,). Therefore, molecular data should be obtained from collections from freshwater habitats to establish whether they are the same species or not. Savoryella lignicola morphologically resembles Savoryella fusiformis and Savoryella longispora (Boonyuen et al., 2011). However, these taxa can easily be distinguished by measurements of length/width ratio of ascospores and molecular data (Ho et al., 1997; Boonyuen et al., 2011).
Description
Savoryella lignicola has;
The sexual morph, ascomata (fruiting body) that is 170-350 μm (Micrometre) high, 120-250 μm in diameter. They are globose, subglobose or ellipsoidal (in shape). They are immersed, partly immersed or superficial, ostiolate (having an ostiole, a small hole or opening), papillate (covered with or bearing papillae or small hairs), membranous, and pale to dark brown.
They have long necks, (48-)80-165 μm long, up to 72 μm in diameter, brown, with periphyses (short, thread-like filaments that line the opening, or ostiole). The peridium (The outer wall of a sporangium or other fruiting body) is brown, one-layered and composed of several layers of thick-walled angular cells forming a textura angularis. The paraphyses (a sterile upward-growing, basally-attached hypha in a hymenium) is present, but sparse.
The asci ascus (the reproductive cell) is 100-(128)-180 × 16-24 μm. It is eight-spored, cylindrical or clavate (club-shaped) in shape. It is short-stalked, unitunicate (enclosed in a single tunic-like layer), persistent, with an apical truncate non-amyloid apical thickening containing a pore.
The ascospores (spores formed in the developing ascus) are 24-36 × 8-12 μm, uni-orbiseriate (arranged in two curved rows), ellipsoidal, tri-septate (having three septa/cell walls), not markedly constricted at the septa. The central cells are brown (10-6-16 μm) with apical cells smaller and hyaline (translucent) and (2.6-6 μm long).
The anamorph or asexual morph is undetermined (modified description of Maharachchikumbura et al., 2016,). Undetermined.
Distribution
Savoryella lignicola has a cosmopolitan distribution, although they are mostly common in tropical and subtropical ecosystems. They are found in places such as; America (including Florida,) Andaman Islands, Australia, Brunei, Canada, China, England, Egypt, Hong Kong, India, Indonesia, Japan, Macau, Malaysia, Maldives, Mauritius, Mexico, New Zealand, Philippines, Portugal, Seychelles, Singapore, South Africa, Sri Lanka, Taiwan, Thailand, and Wales.
They are found in brackish water habitats, as well as marine water habitats. On submerged wood, within water cooling towers, and in rivers and streams. They also can be found in mangrove swamps, (on species of Rhizophora) in Asia including Malaysia.
Uses
Five lignicolous mangrove fungi (Hypoxlon oceanicum, Julella avicenniae, Lignincola laevis, Trematosphaeria mangrovei and Savoryella lignicola) produced extracellular endoglucanase, cellobiohydrolase and β-glucosidase in lab conditions.
References
Sordariomycetes
Fungi described in 1969
Fungus species | Savoryella lignicola | [
"Biology"
] | 1,369 | [
"Fungi",
"Fungus species"
] |
73,599,200 | https://en.wikipedia.org/wiki/Sister%20Beiter%20conjecture | In mathematics, the Sister Beiter conjecture is a conjecture about the size of coefficients of ternary cyclotomic polynomials (i.e. where the index is the product of three prime numbers). It is named after Marion Beiter, a Catholic nun who first proposed it in 1968.
Background
For the maximal coefficient (in absolute value) of the cyclotomic polynomial is denoted by .
Let be three prime numbers. In this case the cyclotomic polynomial is called ternary. In 1895, A. S. Bang proved that . This implies the existence of such that .
Statement
Sister Beiter conjectured in 1968 that . This was later disproved, but a corrected Sister Beiter conjecture was put forward as .
Status
A preprint from 2023 explains the history in detail and claims to prove this corrected conjecture. Explicitly it claims to prove
References
Conjectures about prime numbers
Polynomials | Sister Beiter conjecture | [
"Mathematics"
] | 183 | [
"Polynomials",
"Algebra"
] |
73,599,590 | https://en.wikipedia.org/wiki/Joyride%20%28Friendsound%20album%29 | Joyride is the only album by Friendsound, an alias of the American rock band Brotherhood. Released by RCA Victor in April 1969, the album is an experimental project that originated when the group recorded a spontaneous jam session and "musical free-for-all" with their friends. The record explores an unsettling psychedelic style that features electronic music, musique concrète, spoken word, noisy guitar and other jarring sounds, and incorporates a studio control consol as a musical instrument. One song, "Childsong", features a recording of band member Phil Volk singing as a young child. On release, the album was commercially unsuccessful, although critics praised the music. The album was re-released as part of the 2014 compilation The Complete Recordings.
Recording and production
Joyride is effectively one of three albums by Brotherhood, a group formed by Phil Volk, Drake Levin and Mike "Smitty" Smith after they left Paul Revere & the Raiders in 1967. As with the group's other albums, it was recorded for RCA Victor, but was released under the nom de plume Friendsound. Described by Volk as a "kind of psychedelic adventure into Never-Never Land", on which the group "did some really bizarre things", Joyride built on the sonic experimentation of Brotherhood's 1968 eponymous album, which liberally employed sound effects. Dubbed an "aural portrait of the darker side of Los Angeles life", the album features six compositions rather than 'true' songs, with a generally unsettling nature – such as on "Love Sketch" or the lengthy, cacophonous "Lost Angel Proper St." – that brings irony to the album title. It was inspired by the Mothers of Invention's sprawling Uncle Meat (1969).
The record originated when the group recorded a "musical free-for-all" with their friends; they described it as their first "spontaneous jam session" as well as the first time they employed the studio's control console as a musical instrument. The title track and "Lost Angel Proper St." originate from the session, with flute, dialogue and sound effects overdubbed the following day, while "The Empire of Light", featuring organ, piano and console, was recorded in one take in the night. "Love Sketch" was intended an exercise in new recording techniques which "can be best heard on a true stereo player", while "Childhood's End" and "Childsong" are musique concrète exercises; the former resolves into "triumphant" guitar chords, while the latter is an electronic tone poem recorded at the Dixie Canyon School in San Fernando Valley and the 95th Street School in Los Angeles. In the liner notes, RCA, Ernie Altschuler, Joe Reisman were credited for encouraging Brotherhood to record the album.
Overall, Joyride employs noisy shards of guitar, ticking sounds, spoken word passages and "other jarring effects." The title track – credited to fifteen writers – is a one-chord sound collage "with organ, woodwinds, percussion, guitars and bass, punctuated by spoken interjections", while "Childsong", another sound collage, combines celesta, wind chimes and flute recorder with the sounds of children and Volk's childhood singing. The recording of the younger Volk is one of him singing the songs "On a Slow Boat to China" and "If You Call Everybody Darling", taped several months before his third birthday when his mother took him to a record cutter inside a trailer at a local carnival. He said he sang the songs "impeccably correct, both melody and lyrics", and credited the experience of hearing his voice played back to him with beginning his "musical journey ... with a bang." In a 1998 interview with Sundazed Music, he elaborated:
Volk said that after receiving his test pressing for the album, he was playing "Childsong" when his mother walked in and heard the sampled refrain from his childhood recording, which made her start crying, a memory which he said "still manages to choke him up."
Release and reception
Released by RCA Victor in April 1969, Joyride was commercially unsuccessful and did not chart. In a contemporary review, Lana Harvey of The Edmonton Journal highlighted Friendsound's "funny-peculiar name" and wrote that Joyride consists of musician friends having a "free-for-all" and "a spontaneous (to some degree) jam session," with the "not bad" control console of the recording studio being "utilized as a musical instrument." She praised the album, writing: "Friendsound took a few evenings of beautifully-created music, attached some groovy in-type names to the cuts, like 'Love Sketch', 'Lost Angel Proper St.', 'Childsong,' and a made a nice record. A really nice record." A pop reviewer for Australia's The Age described the album as the "absorbing" result of "overdubbing and multi-taping", and wrote: "Teeny-boppers will be wary of it, but experimental musique concrete, electronic exploration and a certain maturity make this an intriguing disc."
In 2014, Joyride was included alongside Brotherhood's other albums on the compilation The Complete Recordings, released by Real Gone Music. Dan Forte of Vintage Guitar wrote that despite the group's more pop-oriented origins, their music had become "almost purely experimental" by the time of Joyride, drawing attention to the fifteen songwriters credited for the title track. He wrote: "It's a travesty that it's taken 45 years for these albums to resurface and sad to think how much more recognition the late Levin's guitar playing deserved." In his review for The Second Disc, Joe Marchese described Joyride as "very ambitious," but commented that it "lacked the sheer musicality, scope and personality of Zappa's work of the time." Bob Stanley of Record Collector deemed it a "bonkers album".
Friendsound and Joyride were included on the Nurse with Wound list, an influential list of mostly obscure music which influenced the group Nurse with Wound. Psychedelic artist Plastic Crimewave included the album in a list of his favorite music for Dusted Magazine; while noting the confusion between the band name and the album title, he commented that the record as "actually a contract breaker for Paul Revere and the Raiders members, and what a heady one it is! Awesome layered jams that would make Sunburned Hand of the Man blush, and studio fuckery galore! There's even some musique concrete on here!! I recommend fungal enhancement." Julian Cope counted it among several "freak-out albums", alongside those by Amon Düül II, Hapshash and the Coloured Coat and Kalacakra's Crawling to Lhasa (1974), as a noticeable reference point for Karuna Khyal's Alomoni 1985 (1974). Reviewing Broadcast's Mother Is the Milky Way (2009) for Uncut, Jon Dale noted that as an "abstract patchwork", its "jump-cut logic" recalls "late-'60s psychsploitation gems" like Joyride and Andrew Loog Oldham's Gulliver's Travels (1969).
Track listing
Side one (Friendsound I)
"Joyride" (John Barbata, Chris Brooks, Dave Burke, Nino Candido, Ron Collins, Kent Dunbar, Chris Ethridge, Tina Gancher, Buddha Blues, Drake Levin, Flip Mullen, Don Nelson, Mike Smith, Phil Volk, Danny Woody) – 4:15
"Childhood's End" (Collins, Levin, Smith, Volk) – 1:48
"Love Sketch" (Levin, Volk) – 3:26
"Childsong" (Levin, Smith, Nelson, Folk) – 6:12
Side two (Friendsound II)
"Lost Angel Proper St." (Collins, Levin, Nelson, Smith, Volk) – 9:22
"The Empire of Light" (Collins, Levin, Smith, Volk) – 9:40
Personnel
Adapted from the liner notes of Joyride.
Friendsound
Phil Volk – piano ("Joyride"), shovel ("Childhood's End"), bass ("Love Sketch"), prepared piano ("Love Sketch", "The Empire of Light"), celesta ("Childsong")
Drake Levin – guitar ("Joyride", "Lost Angel Proper St."), console ("Childsong", "The Empire of Light")
Michael Smith – drums ("Joyride", "Lost Angel Proper St."), tambourine ("Childhood's End"), shovel ("Childhood's End"), celesta ("Childsong"), console ("The Empire of Light")
Ron Collins – organ ("Joyride", "Childhood's End", "Lost Angel Proper St.", "The Empire of Light")
Friendsound – production, liner notes, chorus ("Joyride", "Lost Angel Proper St.")
Additional personnel
Chris Ethridge – bass ("Joyride", "Lost Angel Proper St.")
Dave Burkey – bass ("Joyride")
Don Nelson – flute ("Joyride", "Love Sketch", "Lost Angel Proper St."), flute recorder ("Childsong"), saxophone ("Lost Angel Proper St.")
Chris Brooks – guitar ("Joyride", "Love Sketch", "Lost Angel Proper St.")
Nino Candido – guitar ("Joyride", "Lost Angel Proper St."), bass ("Lost Angel Proper St.")
Jim Valentine – percussion ("Joyride"), console ("Lost Angel Proper St.")
Kent Dunbar – percussion ("Joyride"), finger cymbals ("Lost Angel Proper St.")
Jerry Cole – bass ("Childhood's End")
Jim Gordon – drums ("Childhood's End")
Grape Lemon – guitar ("Childhood's End"), piano ("Lost Angel Proper St.")
Danny Woody – drums ("Love Sketch")
95th St. School – children ("Childsong")
Dixie Canyon School – children ("Childsong")
Camelia Pad – inspiration ("Lost Angel Proper St.")
Buddha Blues – kinanda ("Lost Angel Proper St.")
Tina Gancher – piano ("Lost Angel Proper St.")
Edina O'Dowd – cover painting
Notes
References
1969 debut albums
RCA Victor albums
Experimental music albums by American artists
Musique concrète albums
Electronic albums by American artists
Psychedelic music albums by American artists
Pop albums by American artists
Field recording | Joyride (Friendsound album) | [
"Engineering"
] | 2,240 | [
"Audio engineering",
"Field recording"
] |
73,600,781 | https://en.wikipedia.org/wiki/Oleaginous%20microorganism | An oleaginous microorganism is a type of microbe that accumulates lipid as a normal part of its metabolism. Oleaginous microbes may accumulate an array of different lipid compounds, including polyhydroxyalkanoates, triacylglycerols, and wax esters. Various microorganisms, including bacteria, fungi, and yeast, are known to accumulate lipids. These organisms are often researched for their potential use in producing fuels from waste products.
Function
For a typical bacteria, polar lipids such as phospholipids are synthesized to maintain the cell membrane. However, in oleaginous organisms, lipids can be synthesized and accumulated within the cell to act as energy storage in nutrient deprived conditions. Lipid accumulation can also serve secondary purposes such as acting as a water source in water stressed conditions, and to prevent oxidative stress from the formation of reactive oxygen species as a result of ultraviolet radiation.
Lipid accumulation occurs as a storage of energy and nutrients, which appears to be triggered by inadequate environmental conditions. Bacteria such as Methylobacterium rhodesianum strain MB126 have been observed to accumulate poly-β-hydroxybutyrate when grown under phosphorus-, nitrogen-, and carbon-deficient conditions. Similarly, other organisms such as oleaginous Rhodococcus species like R. opacus are known to accumulate triacylglycerols instead, with the fatty acid content of these compounds varying by organism and environmental conditions. Lipid accumulation is proposed to be advantageous to oleaginous microbes as it provides a source of energy and nutrients when they are absent from the environment. It allows the organisms to survive through 'feast and famine' conditions, to prevent die offs before a new source of energy and nutrients may be provided to the population.
The specific conditions causing triacylglycerol synthesis and accumulation have been studied in order to develop processes where its intracellular content is maximized. The carbon to nitrogen ratio has been identified as being particularly important for the accumulation of lipids. Conditions with low nitrogen and excess carbon content have been observed to cause increased lipogenesis in bacteria in the genus Rhodococcus.
Lipid accumulation may also provide benefits to organisms in water stressed conditions. The metabolism of triacylglycerols and wax esters have the potential to produce 1.4 molecules of water for each molecule of lipid processed, while poly-β-hydroxybutyrate has a return of 0.5 molecules of water for each molecule of lipid metabolism. Another analysis determined that 107.1g of water can be harvested from 100g of microbial lipids, which is higher than the same amount of carbohydrate storage molecules. This means that oleaginous organisms can rely on lipid storage to reduce water stress and prevent desiccation in arid environments.
Another way that lipid accumulation supports oleaginous microbes survival is the tempering of oxidative stress caused by reactive oxygen species. In environments where ultraviolet radiation is intense, such as deserts or polar regions, microbes can be damaged by the formation of reactive oxygen species from water molecules that interact with the cell's DNA, cellular components, or metabolic processes. Osmolytes such as glycerol – a component of triacylglycerol – stabilize the intracellular water and prevent the formation of reactive oxygen species, preventing cell damage and lysis as a result of ultraviolet radiation.
The genetic component of triacylglycerol biosynthesis has been investigated. Its biosynthesis is catalyzed by the wax ester/acyl-CoA:diacylglycerol acyltransferase enzymes, which is associated with the atf genes, A study investigating the atf genes determines that out of the 10 atf genes identified in R. opacus PD630, only atf1 and aft2 had significant impacts on the activity of the enzymes and the resulting synthesis and accumulation of triacylglycerol.
Source of biofuels
Oleaginous microbes have attracted attention for their potential as sources for biofuels such as biodiesel. Instead of using nonrenewable fuel sources such as petroleum and natural gas, biodiesel has the potential to produce fuel sources from other forms of waste such as agricultural waste or wastewater. Oleaginous microbes have the ability to degrade various different materials into polyhydroxyalkanoates, which may have the potential to form bioplastics, and triacylglycerols, which may have the potential to form biodiesel. Microbes can be integrated into existing processes or waste streams such as wastewater treatment to harvest resources from the waste. Currently, many biofuels are made using plant oils, but products such as single cell oil utilizing microbial lipids require less land and have shorter time constraints compared to the processing of plant oils. Considering both the use of waste as a substrate, the integration into established processes, and the low resource investment, using oleaginous microbes as a source of biofuel is attractive to many researchers.
References
Wikipedia Student Program
Microorganisms
Biofuels | Oleaginous microorganism | [
"Biology"
] | 1,066 | [
"Microorganisms"
] |
73,601,548 | https://en.wikipedia.org/wiki/Zearn | Zearn is an American nonprofit educational software organization founded in 2012. It develops the online education software Zearn Math.
History
In 2012, Zearn was co-founded by CEO Shalinee Sharma and Evan Rudall, former CEO of Uncommon Schools, founded Zearn as a nonprofit organization to develop interactive digital math content for elementary school children. The organization received $4.4 million in grants from the Bill & Melinda Gates Foundation, part of the foundation's $1 billion investment into math education.
The organization develops Zearn Math, an online interactive math curriculum for schoolchildren. As of 2022, it was being used by 25% of US elementary school students and more than one million middle school students according to its own tracking of sign-ons.
Reception
An evaluation report by Johns Hopkins School of Education in 2019 found that overall perceptions of Zearn Math were very positive, with the smaller group model of the curriculum a particular strength. Zearn Math received a green rating for "meets expectations" across all categories of a review by independent nonprofit EdReports. A study by Zearn analyzing the impact of Nebraska's education department's partnership with the company found that students who consistently used the platform had 2.5 times the growth of their state assessment scores than those who did not. However, some parents and teachers in New York criticized the use of the platform for increasing students' screen time, decreasing teachers' instructional time, and focusing on test-preparation rather than critical thinking skills.
References
External links
Software companies based in New York City
2012 establishments in New York City
Non-profit organizations based in New York City
Educational technology companies of the United States
Educational math software
Educational software companies | Zearn | [
"Mathematics"
] | 349 | [
"Educational math software",
"Mathematical software"
] |
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