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67,891,499 | https://en.wikipedia.org/wiki/Plants%20used%20as%20herbs%20or%20spices | This page is a sortable table of plants used as herbs and/or spices. This includes plants used as seasoning agents in foods or beverages (including teas), plants used for herbal medicine, and plants used as incense or similar ingested or partially ingested ritual components.
Table
Definitions of use categories
Culinary: used as a nutritionally minor flavoring component in foods or beverages
Tea: brewed in hot water to make a beverage (for primarily culinary rather than medicinal or ritual purposes)
Medicinal: used, either directly or as a simple extract such as a tea, to cause some physiological effect, usually to treat some ailment or disease
Fragrance: used to add a pleasant odor to food, medicine, or other consumed or partially consumed items (such as incense, candles, or lotions)
Dye: used to alter the color of food, medicine, or other consumed items
Ritual: ingested or partially ingested (eg used as incense) as an important component of a cultural or religious ritual
See also
List of plants used in herbalism
List of culinary herbs and spices
References
Plants and humans
Herbs and spices | Plants used as herbs or spices | [
"Biology"
] | 226 | [
"Plants and humans",
"Humans and other species",
"Plants"
] |
67,892,328 | https://en.wikipedia.org/wiki/Long%20Lived%20In-situ%20Solar%20System%20Explorer | Long Lived In-situ Solar System Explorer (LLISSE) is a possible NASA payload on the Russian Venera-D mission to Venus. LLISSE uses new materials and heat-resistant electronics that would enable independent operation for about 90 Earth days. This endurance may allow it to obtain periodic measurements of weather data to update global circulation models and quantify near surface atmospheric chemistry variability. Its anticipated instruments include wind speed/direction sensors, temperature sensors, pressure sensors, and a chemical multi-sensor array. LLISSE is a small cube of about . The Venera-D lander may carry two LLISSE units; one would be battery-powered (3,000 h), and the other would be wind-powered.
References
Venera program
NASA
Spacecraft instruments
Meteorological instrumentation and equipment
Space science experiments | Long Lived In-situ Solar System Explorer | [
"Astronomy",
"Technology",
"Engineering"
] | 163 | [
"Meteorological instrumentation and equipment",
"Astronomy stubs",
"Measuring instruments",
"Spacecraft stubs"
] |
67,893,191 | https://en.wikipedia.org/wiki/Bergman%27s%20diamond%20lemma | In mathematics, specifically the field of abstract algebra, Bergman's Diamond Lemma (after George Bergman) is a method for confirming whether a given set of monomials of an algebra forms a -basis. It is an extension of Gröbner bases to non-commutative rings. The proof of the lemma gives rise to an algorithm for obtaining a non-commutative Gröbner basis of the algebra from its defining relations. However, in contrast to Buchberger's algorithm, in the non-commutative case, this algorithm may not terminate.
Preliminaries
Let be a commutative associative ring with identity element 1, usually a field. Take an arbitrary set of variables. In the finite case one usually has . Then is the free semigroup with identity 1 on . Finally, is the free associative -algebra over . Elements of will be called words, since elements of can be seen as letters.
Monomial Ordering
The reductions below require a choice of ordering on the words i.e. monomials of . This has to be a total order and satisfy the following:
For all words and , we have that if then .
For each word , the collection is finite.
We call such an order admissible. An important example is the degree lexicographic order, where if has smaller degree than ; or in the case where they have the same degree, we say if comes earlier in the lexicographic order than . For example the degree lexicographic order on monomials of is given by first assuming . Then the above rule implies that the monomials are ordered in the following way:
Every element has a leading word which is the largest word under the ordering which appears in with non-zero coefficient. In if , then the leading word of under degree lexicographic order is .
Reduction
Assume we have a set which generates a 2-sided ideal of . Then we may scale each such that its leading word has coefficient 1. Thus we can write , where is a linear combination of words such that . A word is called reduced with respect to the relations if it does not contain any of the leading words . Otherwise, for some and some . Then there is a reduction , which is an endomorphism of that fixes all elements of apart from and sends this to . By the choice of ordering there are only finitely many words less than any given word, hence a finite composition of reductions will send any to a linear combination of reduced words.
Any element shares an equivalence class modulo with its reduced form. Thus the canonical images of the reduced words in form a -spanning set. The idea of non-commutative Gröbner bases is to find a set of generators of the ideal such that the images of the corresponding reduced words in are a -basis. Bergman's Diamond Lemma lets us verify if a set of generators has this property. Moreover, in the case where it does not have this property, the proof of Bergman's Diamond Lemma leads to an algorithm for extending the set of generators to one that does.
An element is called reduction-unique if given two finite compositions of reductions and such that the images and are linear combinations of reduced words, then . In other words, if we apply reductions to transform an element into a linear combination of reduced words in two different ways, we obtain the same result.
Ambiguities
When performing reductions there might not always be an obvious choice for which reduction to do. This is called an ambiguity and there are two types which may arise. Firstly, suppose we have a word for some non-empty words and assume that and are leading words for some . This is called an overlap ambiguity, because there are two possible reductions, namely and . This ambiguity is resolvable if and can be reduced to a common expression using compositions of reductions.
Secondly, one leading word may be contained in another i.e. for some words and some indices . Then we have an inclusion ambiguity. Again, this ambiguity is resolvable if , for some compositions of reductions and .
Statement of the Lemma
The statement of the lemma is simple but involves the terminology defined above. This lemma is applicable as long as the underlying ring is associative.
Let generate an ideal of , where with the leading words under some fixed admissible ordering of . Then the following are equivalent:
All overlap and inclusion ambiguities among the are resolvable.
All elements of are reduction-unique.
The images of the reduced words in form a -basis.
Here the reductions are done with respect to the fixed set of generators of . When any of the above hold we say that is a Gröbner basis for . Given a set of generators, one usually checks the first or second condition to confirm that the set is a -basis.
Examples
Resolving ambiguities
Take , which is the quantum polynomial ring in 3 variables, and assume . Take to be degree lexicographic order, then the leading words of the defining relations are , and . There is exactly one overlap ambiguity which is and no inclusion ambiguities. One may resolve via or via first. The first option gives us the following chain of reductions,
whereas the second possibility gives,
Since are commutative the above are equal. Thus the ambiguity resolves and the Lemma implies that is a Gröbner basis of .
Non-resolving ambiguities
Let . Under the same ordering as in the previous example, the leading words of the generators of the ideal are , and . There are two overlap ambiguities, namely and . Let us consider . If we resolve first we get,
which contains no leading words and is therefore reduced. Resolving first we obtain,
Since both of the above are reduced but not equal we see that the ambiguity does not resolve. Hence is not a Gröbner basis for the ideal it generates.
Algorithm
The following short algorithm follows from the proof of Bergman's Diamond Lemma. It is based on adding new relations which resolve previously unresolvable ambiguities. Suppose that is an overlap ambiguity which does not resolve. Then, for some compositions of reductions and , we have that and are distinct linear combinations of reduced words. Therefore, we obtain a new non-zero relation . The leading word of this relation is necessarily different from the leading words of existing relations. Now scale this relation by a non-zero constant such that its leading word has coefficient 1 and add it to the generating set of . The process is analogous for inclusion ambiguities.
Now, the previously unresolvable overlap ambiguity resolves by construction of the new relation. However, new ambiguities may arise. This process may terminate after a finite number of iterations producing a Gröbner basis for the ideal or never terminate. The infinite set of relations produced in the case where the algorithm never terminates is still a Gröbner basis, but it may not be useful unless a pattern in the new relations can be found.
Example
Let us continue with the example from above where . We found that the overlap ambiguity does not resolve. This gives us and . The new relation is therefore whose leading word is with coefficient 1. Hence we do not need to scale it and can add it to our set of relations which is now . The previous ambiguity now resolves to either or . Adding the new relation did not add any ambiguities so we are left with the overlap ambiguity we identified above. Let us try and resolve it with the relations we currently have. Again, resolving first we obtain,
On the other hand resolving twice first and then we find,
Thus we have and and the new relation is with leading word . Since the coefficient of the leading word is -1 we scale the relation and then add to the set of defining relations. Now all ambiguities resolve and Bergman's Diamond Lemma implies that
is a Gröbner basis for the ideal it defines.
Further generalisations
The importance of the diamond lemma can be seen by how many other mathematical structures it has been adapted for:
For power series algebras.
For certain quiver Hecke algebras.
For category algebras.
For small categories.
For shuffle operads.
The lemma has been used to prove the Poincaré–Birkhoff–Witt theorem.
References
Lemmas in algebra | Bergman's diamond lemma | [
"Mathematics"
] | 1,698 | [
"Theorems in algebra",
"Lemmas in algebra",
"Lemmas"
] |
67,894,229 | https://en.wikipedia.org/wiki/Guilford%20Quarry%20Pratt%20Through%20Truss%20Bridge | The Guilford Quarry Pratt Through Truss Bridge at Guilford, Maryland is a single-span, metal truss, railroad bridge
History
The bridge was constructed in 1902 to extend a spur of the B&O railroad beyond Savage, Maryland upstream toward a quarry at Guilford Maryland. The town of Guilford at its peak comprised a mill, quarry, and a small village of stone structures.
Guilford was noted for high quality Granite for building structures. The "old Gault" Guilford quarries first started mining Guilford Quartz Monzonite in 1834. They were managed by the Guilford and Waltersville Granite Company in 1887 and later in 1889 by Matthew Gault & Son prior to the bridge installation on the Little Pautuxent river. The river was unnavigable by boat cargo, but the location along the east coast fall-line provided watermill power for mill operations and expansion of industrial applications. These included the 1744 Guilford mill expanded to 50 looms by 1881 as the (Gary Cotton Mill) under the proprietorship of James S. Gary until it burned in 1890. In 1901, the Maryland Granite Company was incorporated, purchasing 200 acres of land including the Gault quarry, Lohman and Earp Farms, and Gary Mill property. A standard-gauge railroad extension from the Savage Mill spur of the B&O railroad was started on an escarpment along the river. In addition to the bridge, a steam plant, electric plant, telephone & telegraph lines, air compressor for steel-shot cutting, 20-ton overhead crane and additional houses for employees were planned under the supervision of James J. Miller. The anticipation was to have 200 stonecutters in operation filling three railcars of rough stone daily enabled by the bridge.
The majority of the towns historic structures have since been demolished or displaced by development of the Columbia, Maryland project village of Kings Contrivance, leaving only the bridge and quarry remnants for preservation.
On June 2, 2021, the Guilford Quarry Pratt Through Truss Bridge was registered on the National Register of Historic Places.
Description
The Guilford Quarry Pratt Through Truss Bridge crosses the Little Patuxent River in Howard County Maryland.
See also
List of bridges documented by the Historic American Engineering Record in Maryland
List of Historic Civil Engineering Landmarks
List of bridges on the National Register of Historic Places in Maryland
List of Howard County properties in the Maryland Historical Trust
List of National Historic Landmarks in Maryland
National Register of Historic Places listings in Howard County, Maryland
References
External links
National Historic Landmark information
Baltimore and Ohio Railroad bridges
Bridges in Howard County, Maryland
Railroad bridges in Maryland
Truss bridges in the United States
Bridges completed in 1902
Historic Civil Engineering Landmarks
Railroad bridges on the National Register of Historic Places in Maryland
Railroad-related National Historic Landmarks
National Historic Landmarks in Maryland
Historic American Engineering Record in Maryland
National Register of Historic Places in Howard County, Maryland
Suspension bridges in Maryland | Guilford Quarry Pratt Through Truss Bridge | [
"Engineering"
] | 573 | [
"Civil engineering",
"Historic Civil Engineering Landmarks"
] |
67,894,577 | https://en.wikipedia.org/wiki/RAC%20421-II | RAC 421-II, also referred to simply as RAC 421, is a quaternary local anesthetic that acts through intracellular blockage of the NaKATPase channel.
Function
As a quaternary ammonium analogue of another local anesthetic, RAC 109, RAC 421-II is permanently charged and so cannot cross the hydrophobic phospholipid cell membrane. As it cannot diffuse across the cell membrane, it cannot exert its inhibitory effects on the intracellular surface of NaKATPase. As such, it can only exert its anesthetic properties if it is injected into the cytosol of the nerve fibre. Inhibition occurs through allowing the sodium and potassium gradients across the cell membrane to dissipate. NaKATPase blockage preferentially inhibits firing of nociceptive nerve fibres due to their relatively low cell diameter and so low tolerance to NaKATPase inhibitors.
This is in contrast to non-quaternary anesthetics like benzocaine and tetracaine which cross the cell membrane in their uncharged states and so they can induce anesthetic effects upon application to the extracellular side of the membrane. They subsequently become charged and so activated within the cytosol to exert their inhibitory effects on NaKATPase (NaKATPase inhibiting anesthetics must be in their charged state to become active).
References
Local anesthetics
Pyrrolidones
Spiro compounds
Tetralins | RAC 421-II | [
"Chemistry"
] | 311 | [
"Organic compounds",
"Spiro compounds"
] |
67,895,571 | https://en.wikipedia.org/wiki/World%20energy%20supply%20and%20consumption | World energy supply and consumption refers to the global supply of energy resources and its consumption. The system of global energy supply consists of the energy development, refinement, and trade of energy. Energy supplies may exist in various forms such as raw resources or more processed and refined forms of energy. The raw energy resources include for example coal, unprocessed oil & gas, uranium. In comparison, the refined forms of energy include for example refined oil that becomes fuel and electricity. Energy resources may be used in various different ways, depending on the specific resource (e.g. coal), and intended end use (industrial, residential, etc.). Energy production and consumption play a significant role in the global economy. It is needed in industry and global transportation. The total energy supply chain, from production to final consumption, involves many activities that cause a loss of useful energy.
As of 2022, energy consumption is still about 80% from fossil fuels. The Gulf States and Russia are major energy exporters. Their customers include for example the European Union and China, who are not producing enough energy in their own countries to satisfy their energy demand. Total energy consumption tends to increase by about 1–2% per year. More recently, renewable energy has been growing rapidly, averaging about 20% increase per year in the 2010s.
Two key problems with energy production and consumption are greenhouse gas emissions and environmental pollution. Of about 50 billion tonnes worldwide annual total greenhouse gas emissions, 36 billion tonnes of carbon dioxide was a result of energy use (almost all from fossil fuels) in 2021. Many scenarios have been envisioned to reduce greenhouse gas emissions, usually by the name of net zero emissions.
There is a clear connection between energy consumption per capita, and GDP per capita.
A significant lack of energy supplies is called an energy crisis.
Primary energy production
Primary Energy refers to first form of energy encountered, as raw resources collected directly from energy production, before any conversion or transformation of the energy occurs.
Energy production is usually classified as:
Fossil, using coal, crude oil, and natural gas;
Nuclear, using uranium;
Renewable, using biomass, geothermal, hydropower, solar, wind, tidal, wave, among others.
Primary energy assessment by IEA follows certain rules to ease measurement of different kinds of energy. These rules are controversial. Water and air flow energy that drives hydro and wind turbines, and sunlight that powers solar panels, are not taken as PE, which is set at the electric energy produced. But fossil and nuclear energy are set at the reaction heat, which is about three times the electric energy. This measurement difference can lead to underestimating the economic contribution of renewable energy.
Enerdata displays data for "Total energy / production: Coal, Oil, Gas, Biomass, Heat and Electricity" and for "Renewables / % in electricity production: Renewables, non-renewables".
The table lists worldwide PE and the countries producing most (76%) of that in 2021, using Enerdata. The amounts are rounded and given in million tonnes of oil equivalent per year (1 Mtoe = 11.63 TWh (41.9 petajoules), where 1 TWh = 109 kWh) and % of Total. Renewable is Biomass plus Heat plus renewable percentage of Electricity production (hydro, wind, solar). Nuclear is nonrenewable percentage of Electricity production. The above-mentioned underestimation of hydro, wind and solar energy, compared to nuclear and fossil energy, applies also to Enerdata.
The 2021 world total energy production of 14,800 MToe corresponds to a little over 172 PWh / year, or about 19.6 TW of power generation.
Energy conversion
Energy resources must be processed in order to make it suitable for final consumption. For example, there may be various impurities in raw coal mined or raw natural gas that was produced from an oil well that may make it unsuitable to be burned in a power plant.
Primary energy is converted in many ways to energy carriers, also known as secondary energy:
Coal mainly goes to thermal power stations. Coke is derived by destructive distillation of bituminous coal.
Crude oil goes mainly to oil refineries
Natural-gas goes to natural-gas processing plants to remove contaminants such as water, carbon dioxide and hydrogen sulfide, and to adjust the heating value. It is used as fuel gas, also in thermal power stations.
Nuclear reaction heat is used in thermal power stations.
Biomass is used directly or converted to biofuel.
Electricity generators are driven by steam or gas turbines in a thermal plant, or water turbines in a hydropower station, or wind turbines, usually in a wind farm. The invention of the solar cell in 1954 started electricity generation by solar panels, connected to a power inverter. Mass production of panels around the year 2000 made this economic.
Energy trade
Much primary and converted energy is traded among countries. The table lists countries with large difference of export and import in 2021, expressed in Mtoe. A negative value indicates that much energy import is needed for the economy. Russian gas exports were reduced a lot in 2022, as pipelines to Asia plus LNG export capacity is much less than the gas no longer sent to Europe.
Transport of energy carriers is done by tanker ship, tank truck, LNG carrier, rail freight transport, pipeline and by electric power transmission.
Total energy supply
Total energy supply (TES) indicates the sum of production and imports subtracting exports and storage changes. For the whole world TES nearly equals primary energy PE because imports and exports cancel out, but for countries TES and PE differ in quantity, and also in quality as secondary energy is involved, e.g., import of an oil refinery product. TES is all energy required to supply energy for end users.
The tables list TES and PE for some countries where these differ much, both in 2021 and TES history. Most growth of TES since 1990 occurred in Asia. The amounts are rounded and given in Mtoe. Enerdata labels TES as Total energy consumption.
25% of worldwide primary production is used for conversion and transport, and 6% for non-energy products like lubricants, asphalt and petrochemicals. In 2019 TES was 606 EJ and final consumption was 418 EJ, 69% of TES. Most of the energy lost by conversion occurs in thermal electricity plants and the energy industry own use.
Discussion about energy loss
There are different qualities of energy. Heat, especially at a relatively low temperature, is low-quality energy, whereas electricity is high-quality energy. It takes around 3 kWh of heat to produce 1 kWh of electricity. But by the same token, a kilowatt-hour of this high-quality electricity can be used to pump several kilowatt-hours of heat into a building using a heat pump. Electricity can be used in many ways in which heat cannot. So the loss of energy incurred in thermal electricity plants is not comparable to a loss due to, say, resistance in power lines, because of quality differences.
In fact, the loss in thermal plants is due to poor conversion of chemical energy of fuel to electricity by combustion. Chemical energy of fuel is not inherently low-quality; for example, conversion to electricity in fuel cells can theoretically approach 100%. So energy loss in thermal plants is real loss.
Final consumption
Total final consumption (TFC) is the worldwide consumption of energy by end-users (whereas primary energy consumption (Eurostat) or total energy supply (IEA) is total energy demand and thus also includes what the energy sector uses itself and transformation and distribution losses). This energy consists of fuel (78%) and electricity (22%). The tables list amounts, expressed in million tonnes of oil equivalent per year (1 Mtoe = 11.63 TWh) and how much of these is renewable energy. Non-energy products are not considered here. The data are of 2018. The world's renewable share of TFC was 18% in 2018: 7% traditional biomass, 3.6% hydropower and 7.4% other renewables.
In the period 2005–2017 worldwide final consumption of coal increased by 23%, of oil and gas increased by 18%, and that of electricity increased by 41%.
Fuel comes in three types: Fossil fuel is natural gas, fuel derived from petroleum (LPG, gasoline, kerosene, gas/diesel, fuel oil), or from coal (anthracite, bituminous coal, coke, blast furnace gas). Secondly, there is renewable fuel (biofuel and fuel derived from waste). And lastly, the fuel used for district heating.
The amounts of fuel in the tables are based on lower heating value.
The first table lists final consumption in the countries/regions which use most (85%), and per person as of 2018. In developing countries fuel consumption per person is low and more renewable. Canada, Venezuela and Brazil generate most electricity with hydropower.
The next table shows countries consuming most (85%) in Europe.
Energy for energy
Some fuel and electricity is used to construct, maintain and demolish/recycle installations that produce fuel and electricity, such as oil platforms, uranium isotope separators and wind turbines. For these producers to be economical the ratio of energy returned on energy invested (EROEI) or energy return on investment (EROI) should be large enough.
If the final energy delivered for consumption is E and the EROI equals R, then the net energy available is E-E/R. The percentage available energy is 100-100/R. For R>10 more than 90% is available but for R=2 only 50% and for R=1 none. This steep decline is known as the net energy cliff.
Availability of data
Many countries publish statistics on the energy supply and consumption of either their own country, of other countries of interest, or of all countries combined in one chart. One of the largest organizations in this field, the International Energy Agency (IEA), sells yearly comprehensive energy data which makes this data paywalled and difficult to access for internet users. The organization Enerdata on the other hand publishes a free Yearbook, making the data more accessible. Another trustworthy organization that provides accurate energy data, mainly referring to the USA, is the U.S. Energy Information Administration.
Trends and outlook
Due to the COVID-19 pandemic, there was a significant decline in energy usage worldwide in 2020, but total energy demand worldwide had recovered by 2021, and has hit a record high in 2022.
In 2022, consumers worldwide spent nearly USD 10 trillion on energy, averaging more than USD 1,200 per person. This reflects a 20% increase over the previous five-year average, highlighting the significant economic impact and the increasing financial burden of energy consumption on a global scale.
IEA scenarios
In World Energy Outlook 2023 the IEA notes that "We are on track to see all fossil fuels peak before 2030". The IEA presents three scenarios:
The Stated Policies Scenario (STEPS) provides an outlook based on the latest policy settings. The share of fossil fuel in global energy supply – stuck for decades around 80% – starts to edge downwards and reaches 73% by 2030. This undercuts the rationale for any increase in fossil fuel investment. Renewables are set to contribute 80% of new power capacity to 2030, with solar PV alone accounting for more than half. The STEPS sees a peak in energy-related CO2 emissions in the mid-2020s but emissions remain high enough to push up global average temperatures to around 2.4 °C in 2100. Total energy demand continues to increase through to 2050. Total energy investment remains at about US$3 trillion per year.
The Announced Pledges Scenario (APS) assumes all national energy and climate targets made by governments are met in full and on time. The APS is associated with a temperature rise of 1.7 °C in 2100 (with a 50% probability). Total energy investment rises to about US$4 trillion per year after 2030.
The Net Zero Emissions by 2050 (NZE) Scenario limits global warming to 1.5 °C. The share of fossil fuel reaches 62% in 2030. Methane emissions from fossil fuel supply cuts by 75% in 2030. Total energy investment rises to almost US$5 trillion per year after 2030. Clean energy investment needs to rise everywhere, but the steepest increases are needed in emerging market and developing economies other than China, requiring enhanced international support. The share of electricity in final consumption exceeds 50% by 2050 in NZE. The share of nuclear power in electricity generation remains broadly stable over time in all scenarios, about 9%.
The IEA's "Electricity 2024" report details a 2.2% growth in global electricity demand for 2023, forecasting an annual increase of 3.4% through 2026, with notable contributions from emerging economies like China and India, despite a slump in advanced economies due to economic and inflationary pressures. The report underscores the significant impact of data centers, artificial intelligence and cryptocurrency, projecting a potential doubling of electricity consumption to 1,000 TWh by 2026, which is on par with Japan's current usage. Notably, 85% of the additional demand is expected to originate from China and India, with India's demand alone predicted to grow over 6% annually until 2026, driven by economic expansion and increasing air conditioning use.
Southeast Asia's electricity demand is also forecasted to climb by 5% annually through 2026. In the United States, a decrease was seen in 2023, but a moderate rise is anticipated in the coming years, largely fueled by data centers. The report also anticipates that a surge in electricity generation from low-emissions sources will meet the global demand growth over the next three years, with renewable energy sources predicted to surpass coal by early 2025.
Alternative scenarios
The goal set in the Paris Agreement to limit climate change will be difficult to achieve. Various scenarios for achieving the Paris Climate Agreement Goals have been developed, using IEA data but proposing transition to nearly 100% renewables by mid-century, along with steps such as reforestation. Nuclear power and carbon capture are excluded in these scenarios. The researchers say the costs will be far less than the $5 trillion per year governments currently spend subsidizing the fossil fuel industries responsible for climate change.
In the +2.0 C (global warming) Scenario total primary energy demand in 2040 can be 450 EJ = 10,755 Mtoe, or 400 EJ = 9560 Mtoe in the +1.5 Scenario, well below the current production. Renewable sources can increase their share to 300 EJ in the +2.0 C Scenario or 330 EJ in the +1.5 Scenario in 2040. In 2050 renewables can cover nearly all energy demand. Non-energy consumption will still include fossil fuels.
Global electricity generation from renewable energy sources will reach 88% by 2040 and 100% by 2050 in the alternative scenarios. "New" renewables—mainly wind, solar and geothermal energy—will contribute 83% of the total electricity generated. The average annual investment required between 2015 and 2050, including costs for additional power plants to produce hydrogen and synthetic fuels and for plant replacement, will be around $1.4 trillion.
Shifts from domestic aviation to rail and from road to rail are needed. Passenger car use must decrease in the OECD countries (but increase in developing world regions) after 2020. The passenger car use decline will be partly compensated by strong increase in public transport rail and bus systems.
CO2 emission can reduce from 32 Gt in 2015 to 7 Gt (+2.0 Scenario) or 2.7 Gt (+1.5 Scenario) in 2040, and to zero in 2050.
See also
Lists
List of countries by energy intensity
List of countries by electricity consumption
List of countries by electricity production
List of countries by energy consumption per capita
List of countries by greenhouse gas emissions
List of countries by energy consumption and production
Notes
References
External links
Enerdata - World Energy & Climate Statistics
International Energy Outlook, by the U.S. Energy Information Administration
World Energy Outlook from the IEA
Energy policy
Energy economics
Energy by region
Energy consumption
Human ecology
Global environmental issues
World
Energy production | World energy supply and consumption | [
"Environmental_science"
] | 3,365 | [
"Energy economics",
"Environmental social science",
"Human ecology",
"Energy policy"
] |
67,895,670 | https://en.wikipedia.org/wiki/Maleic%20hydrazide | Maleic hydrazide, often known by the brand name Fazor is a plant growth regulator that reduces growth through preventing cell division but not cell enlargement. It is applied to the foliage of potato, onion, garlic and carrot crops to prevent sprouting during storage. It can also be used to control volunteer potatoes that are left in the field during harvesting. It was first identified in the 1940s but was not used commercially in the United Kingdom until 1984. The banning of chlorpropham as a sprout suppressant in 2019 has led renewed interest in how maleic hydrazide can be used in potatoes.
References
Hydrazides
Plant growth regulators | Maleic hydrazide | [
"Chemistry"
] | 137 | [
"Organic chemistry stubs"
] |
67,899,343 | https://en.wikipedia.org/wiki/Tayyaba%20Zafar | Tayyaba Zafar (born 29 May 1983) is a Pakistani-born astronomer and science communicator. She is widely known to the public as the first woman from Pakistan who visited Antarctica under the Homeward Bound Program. She completed her PhD in astronomy from the University of Copenhagen, Denmark in 2011 and worked at the European Southern Observatory and Australian Astronomical Observatory. She researches how metals and dust form in distant galaxies and their effects are on star formation and other galaxy properties.
Early life and education
Zafar was born and grew up in Lahore, Pakistan. She completed her PhD in 2011, at the Dark Cosmology Center, University of Copenhagen with a thesis entitled Spectroscopy of high redshift sightlines. This started her astrophysics career working on interstellar medium studies.
Research career
After completing her PhD, Zafar accepted a postdoctoral position at the Laboratorie d’Astrophysique de Marseille, France. In 2013, she moved to Germany to take up a fellowship at the European Southern Observatory (ESO). She later accepted a Research Astronomer role at the Australian Astronomical Observatory. She moved to Australia in November 2015, and supported the Anglo Australian Telescope at the Siding Spring Observatory. In mid-2018, she was hired by Macquarie University where she is currently serving as a Senior-Lecturer.
Her research focuses on the obscured universe and its connection with properties of galaxies. As of June 2021, SAO/NASA Astrophysics Data System lists her 59 refereed publications.
Science communication
Dr Zafar became recognised as a public figure when she visited Antarctica in 2018 under the Homeward Bound project, a personal and professional development program to empower STEMM women leaders. She has given public talks such as for Sydney Science Festival, talks to amateur astronomical societies, schools, and universities and written scientific online articles. She is a member of the 2021 CSIRO STEM Professionals in Schools, Australia program to team up with teachers to educate and inspire students. She has given multi-lingual TV interviews, including a one-to-one interview for Such TV and breakfast show with Lahore News TV. She has radio and print interviews including interviews for BBC World, ABC News, SBS, and EFE Verde. She has online articles on astronomy, instrumentation, and women in STEM issues. She has been invited as a panelist for women in STEM discussion panels e.g., Sydney Science Trail in 2020.
Awards
2020 NSW Young Tall Poppy Science Award for scientific contributions and communications in Australia.
Selected publications
Zafar, T., D. Watson, J. P. U. Fynbo, D. Malesani, P. Jakobsson, and A. de Ugarte Postigo 2011. The extinction curves of star-forming regions from z = 0.1 to 6.7 using GRB afterglow spectroscopy. Astronomy and Astrophysics 532, A143. 2011A&A...532A.143Z
Zafar, T., C. Péroux, A. Popping, B. Milliard, J.-M. Deharveng, and S. Frank 2013. The ESO UVES advanced data products quasar sample. II. Cosmological evolution of the neutral gas mass density. Astronomy and Astrophysics 556, A141. 2013A&A...556A.141Z
Zafar, T. and D. Watson 2013. The metals-to-dust ratio to very low metallicities using GRB and QSO absorbers; extremely rapid dust formation. Astronomy and Astrophysics 560, A26. 2013A&A...560A..26Z
References
Pakistani astronomers
Women astronomers
21st-century astronomers
1983 births
21st-century Pakistani scientists
21st-century women scientists
Living people
Science communicators
Scientists from Lahore
University of the Punjab alumni
University of Copenhagen alumni
Academic staff of Macquarie University
Pakistani emigrants to Australia | Tayyaba Zafar | [
"Astronomy"
] | 784 | [
"Women astronomers",
"Astronomers"
] |
70,788,340 | https://en.wikipedia.org/wiki/AF%20Andromedae | AF Andromedae (AF And) is a luminous blue variable (LBV), a type of variable star. The star is one of the most luminous variables in M31, the Andromeda Galaxy.
Discovery
The star was discovered to be variable in 1927, with a photographic magnitude range of 15.3 to 16.5, at the Harvard College Observatory and designated HV 4013. It was considered to be the brightest variable star in M31. Two years later it was given the variable star designation AF Andromedae. Between 1917 and 1953, five or six major eruptions were detected and two or three minor ones. More eruptions were observed in 1970-74, 1987-92, 1998-2001, and 2017.
AF And was often referred to as var 19, after its number in a Hubble list of variable stars in M31 and M33. It was identified as one of the five Hubble–Sandage variables: Var A, Var B, Var C, and Var 2 in M33, and Var 19 in M31. On the basis of color–color comparisons, it was assigned as spectral type B and described as related to the P Cygni variables. Observations from 1960 to 1970 showed irregular variations in the B (blue) magnitude between 15.5 and 17.6, with visual magnitudes somewhat brighter. The first detailed spectrum was published in 1975.
Spectrum
AF And in outbursts has a peculiar emission line spectrum described as very much like Eta Carinae, likely due to a dense stellar wind. When quiescent, the spectrum is similar to late Of or WN stars.
AF And has prominent allowed and forbidden FeII and hydrogen lines in its emission spectrum, as well as weaker HeI lines. The variability and lack of absorption lines defy a normal spectral classification, but it was suggested that it may be close to class A.
The 250.7 nm FeII line is unusually strong in emission. The same feature in Eta Carinae's spectrum has been attributed to a UV laser.
Properties
AF And was the brightest star in M31 when it was first noticed during an outburst, at an apparent magnitude around 15, over a million times more luminous than the Sun. Newer calculations give a luminosity slightly less than a million times that of the Sun.
The star's mass has not been calculated explicitly, but this type of star is massive, typically .
See also
List of Andromeda's satellite galaxies
M31-RV
References
Andromeda (constellation)
Andromeda Galaxy
Extragalactic stars
Luminous blue variables
Andromedae, AF
?
Stars in the Andromeda Galaxy | AF Andromedae | [
"Astronomy"
] | 536 | [
"Andromeda (constellation)",
"Constellations"
] |
70,794,858 | https://en.wikipedia.org/wiki/Entoloma%20porphyrophaeum | Entoloma porphyrophaeum is a species of agaric (gilled mushroom) in the family Entolomataceae. It has been given the recommended English name of Lilac Pinkgill. The species has a European distribution, occurring mainly in agriculturally unimproved grassland. Entoloma porphyrophaeum has been reported from North America, but at least some of these reports represent a distinct species, Entoloma canadense. Threats to its habitat have resulted in the Lilac Pinkgill being assessed as globally "vulnerable" on the IUCN Red List of Threatened Species.
Taxonomy
The species was first described by Swedish mycologist Elias Magnus Fries in 1857 as Agaricus porphyrophaeus, the epithet derived from Ancient Greek πορφύρα ("purple") and φαιός ("dusky"). Finnish mycologist Petter Adolf Karsten transferred it to the genus Entoloma in 1879.
Description
Basidiocarps are agaricoid, up to 175 mm (7 in) tall, the cap conical at first becoming convex to flat and broadly umbonate, up to 145 mm (5.5 in) across. The cap surface is smooth, finely fibrillose, lilac to purple-brown becoming brown. The lamellae (gills) are white to cream becoming pink from the spores. The stipe (stem) is smooth, finely fibrillose, cap-coloured or paler, lacking a ring. The spore print is pink, the spores (under a microscope) multi-angled, inamyloid, measuring about 8 to 12 by 6 to 8 μm. The cheilocystidia are rostrate (with a simple apical projection) to capitate (with a spherical apical projection).
Similar species
Entoloma porphyrophaeum belongs in the "Trichopilus" group of Entoloma species and is similar to the commoner Entoloma jubatum, which is typically smaller and darker with distinctly brown lamellae. Entoloma fuscomarginatum and E, elodes are species of Sphagnum and peat bogs, the former with a brown edge to the lamellae.
Distribution and habitat
The Lilac Pinkgill is rare but widespread in Europe. Like many other European pinkgills, it occurs in old, agriculturally unimproved, short-sward grassland (pastures and lawns).
Conservation
Entoloma porphyrophaeum is typical of waxcap grasslands, a declining habitat due to changing agricultural practices. As a result, the species is of global conservation concern and is listed as "vulnerable" on the IUCN Red List of Threatened Species.
References
Entolomataceae
Fungi described in 1857
Fungi of Europe
Taxa named by Elias Magnus Fries
Fungus species | Entoloma porphyrophaeum | [
"Biology"
] | 593 | [
"Fungi",
"Fungus species"
] |
70,795,393 | https://en.wikipedia.org/wiki/HD%2064307 | HD 64307, also known as HR 3075, is a solitary, orange hued star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.35, allowing it to be faintly seen with the naked eye. Based on parallax measurements from the Gaia spacecraft, The object is estimated to be 690 light years distant. It appears to be receding from the Sun, having a heliocentric radial velocity of .
HD 64307 is an evolved star with a stellar classification of K3 III. Gaia DR3 stellar evolution models place it on the red giant branch. It has a mass comparable to the Sun but due to its evolved state, it has an enlarged radius of . It shines with a bolometric luminosity of from its photosphere at an effective temperature of 4,264 K. HD 64307 has an iron abundance 80% that of the Sun, and is also lithium enriched. Like most giant stars, the object spins slowly, having a projected rotational velocity lower than .
References
Camelopardalis
K-type giants
064307
3075
039117
BD+74 338 | HD 64307 | [
"Astronomy"
] | 244 | [
"Camelopardalis",
"Constellations"
] |
70,796,522 | https://en.wikipedia.org/wiki/Chemical%20defenses%20in%20Cannabis | Cannabis (/ˈkænəbɪs/) is commonly known as marijuana or hemp and has two known strains: Cannabis sativa and Cannabis indica, both of which produce chemicals to deter herbivory. The chemical composition includes specialized terpenes and cannabinoids, mainly tetrahydrocannabinol (THC), and cannabidiol (CBD). These substances play a role in defending the plant from pathogens including insects, fungi, viruses and bacteria. THC and CBD are stored mostly in the trichomes of the plant, and can cause psychological and physical impairment in the user, via the endocannabinoid system and unique receptors. THC increases dopamine levels in the brain, which attributes to the euphoric and relaxed feelings cannabis provides. As THC is a secondary metabolite, it poses no known effects towards plant development, growth, and reproduction. However, some studies show secondary metabolites such as cannabinoids, flavonoids, and terpenes are used as defense mechanisms against biotic and abiotic environmental stressors.
Biosynthesis pathways
Cannabinoids
The production of the cannabinoids THC and CBD are a result of a series of chemical reactions, and are just two types of over a hundred that are known. Inside the transcriptomes of glandular trichomes in the cannabis plant, the pathway for cannabinoid production takes place. Beginning with the formation of 3,5,7-trioxododecaneoyl-COA by the condensation reaction between hexanoyl-CoA and malonyl-CoA, catalyzed by type III polyketide synthase (PKS), the product is then used to form olivetolic acid. After the geranylation of olivetolic acid, cannabigerolic acid (CBGA) or cannabigerivarinic acid (CBGVA) is formed. The decarboxylation of these acids yield what we recognize as THC and CBD.
Terpenes
Terpenes are a key component in chemotaxonomical classification of cannabis strains as terpene composition is a phenotypic trait. Majority of terpenes found in cannabis are hydrocarbons, which are a direct product of terpene synthase (TPS) enzymes. The molecular make up of terpenes in a cannabis plant involves the linking and elongation of chains in hydrocarbons and isoprene units, formed by isopentenyl pyrophosphate and dimethylallyl pyrophosphate. Terpenoids are basically terpenes with the addition of oxygen, among other structural additions. There are numerous types of unique functional terpenes in green plants and are formed via many differing pathways; methylerythritol phosphate (MEP), cytosolic mevalonate (MEV), or deoxyxylulose phosphate pathway (DOXP) to name a few. In addition, mevalonic acid's (MVA) involvement in biosynthesis of complex terpenoids, such as steroids, was demonstrated in 1983. Once produced, specifically within the disk cells, terpenes are stored within the trichomes of the plant. There are several types of terpenes in cannabis composed of varying numbers of isoprene units. They contribute to the signature aroma and insecticidal properties via their emission as volatile organic compounds. Different cannabis strains synthesize different terpenes through their biochemical pathways, and diversity of the terpenes is dependent upon the diversity of the TPS enzymes present in the cannabis plant's TPS gene pool. Though, causes of variations in the TPS enzymes are still unknown.
Monoterpenes myrcene and sesquiterpenes β-caryophyllene (binds to the human CB2 cannabinoids receptor) and α-humulene are the most common terpene compounds, and are present in most varieties of cannabis strains. The lack of exact standards makes it sometimes difficult for scientists to classify new terpenes. Terpene profiles are subject to change under different environmental conditions, which may lead to variation in TPS gene expression, ultimately leading to a variation in the synthesized terpenes. Terpenes have unique, distinct aromas, which is why each strain smells different. Cannabis plants, like many others, biochemically synthesize terpenes with intense aromas as a method of chemical defense in attempts to repel predators, and invite pollinators. Because terpenes and terpenoids are biologically active molecules, it is possible variations in terpenes may elicit different biological and psychoactive responses in humans. This is why people claim to have different psychological effects to different strains.
Chemical biotic stress defense
One form of Cannabis defense is the up-regulation of cannabinoids and specialized terpenes in response to differing biotic stressors in the environment such as pests and predation. In a study from 2019, tobacco hornworm larvae were fed on an artificial diet of wheat germ containing a cannabis agent. The results showed that on average, significantly high dosages of CBD in the new diet may have decreased survival rates of the larvae. In addition, Maduca sexta larvae avoids eating plants containing high amounts of CBD, allowing for the indication that CBD may be a natural pest deterrent. However, research also has shown when the plant is subjected to mechanical wounds from certain insects, CBD levels were unchanged and even decreased. This observation may be due to difference in the species of insect and chemical secretions, thus providing a new hypothesis that CBD levels vary in response to certain species or even have no effect.
Phytocannabinoid and terpene content in the leaves and flowers of C. sativa rises when under attack by Tetranychus urticae, a common pest for the genus. When compared to a control of Cannabis sativa without any pest damage, research from 2022 demonstrated an overall increase of secondary metabolites in plants exposed to Tetranychus urtivae infestation and measured this metabolite rise using liquid and gas chromatograph mass spectrometers. The increase was found to be significant, and is attributed as a defense mechanism in the plant.
The induction and up-regulation of cannabinoids as defense genes in Cannabis can be induced by elicitors. In a study from 2019, salicylic acid (SA) was used with GABA as an elicitor to determine its effects on the expression of metabolites involved in THC and CBD biosynthesis. SA and GABA were demonstrated to effectively up-regulate the expression of THCAS, a cannabigerolic acid used to form THC, which resulted in higher levels of THC. These results support the mechanism in which cannabis elicitors such as salicylic acid and GABA triggers a signal cascade for increased expression of defense genes in response to stress.
One line of defense is the release of volatile organic compounds (VOCs) into the air to defend against herbivores by warning neighboring plants. The release of VOCs may begin with the jasmonic (JA) pathway which up-regulates defensive genes. Jasmonic acid, also called jasmonate, is a hormone linked to wound signaling in plants. Rapid wound signaling involves an influx of calcium after the arrival of an action potential. The increase of calcium triggers a regulatory protein, calmodulin, to turn on a protein kinase releasing JASMONATE-ASSOCIATED VQ-MOTIF GENE1 (JAV1) by combining it with phosphoric acid. From a study in 2020, in response to the necrotrophic pathogen gray mold, JA mediated markers were up-regulated in the leaves that were infected, from beginning of infection to the end. Through a series of signals, the plant detects the presence of fungal elicitors/pathogens, then through the JA pathway the expression of defense genes are increased.
Chemical abiotic stress defense
Drought resistance
Drought poses negative impacts to growth and yield of hemp, therefore, hemp has evolved survival mechanisms for abiotic stress. Plant cells will discontinue normal growth rates when exposed to drought stress along with other physiological processes such as photosynthesis. Down regulating certain gene's expressions or transcription factors can assist in this response. For example, photosynthesis–antenna proteins and differentially expressed genes (DEGs) in the jasmonic acid pathway were demonstrated as being down-regulated during drought stress. In a 2018 research article by Gao, they attribute the down regulation to reduced photosynthesis in the plant. Up regulating genes can also occur, such as transcriptional factors from the NAC gene family, which were demonstrated to be over expressed in response to drought treatments, possibly contributing to tolerance. Numerous regulation genes involved in the biosynthesis of abscisic acid (ABA), a plant hormone linked to stress response, are over expressed during times of drought stress. Some of these genes are from the PP2C and SnPK gene families, linked to drought tolerance because of their intrinsic roles of ABA signaling. ABA signaling, controlled by changes in ABA metabolic pathways, assist in stomata closure and changes in the photosynthesis processes in hemp plants to combat water loss during drought stress.
Another stress hormone, auxin, may be important in drought tolerance by means of the gene GH3. A hemp GH3 homolog gene has been shown to increase drought resistance in rice by decreasing expression of Indole-3-Acetic Acid (IAA), which decreases photosynthesis and cell growth.
Salt stress
Ion balance is a key factor in plant development to produce yield. Too high salt concentration in soil lowers the water potential in root tissue which becomes toxic; stunting growth and inhibiting flowering by dehydrating the plant. Stomatal closure is also a response to high salinity, leading to lowered sugar production and transpiration rates. Plants respond to high salinity soils by accumulating sodium and chlorine, and reducing uptake of macronutrients and other ions. This accumulation results in inhibition of calcium signaling. In order to combat this type of stress, plants must have strategies and adaptations in place for survival, such as osmotic stress pathways. RNA sequencing and qRT-PCR analysis has made finding these gene expression pathways possible, such as the MAPK, allowing for the scrutiny of candidate genes responsible for greater tolerance to salinity. Candidate genes for this type of stress response have also been found in plant hormone signal transduction pathways. Different species of Cannabis carry unique variations of gene expression, with some having a greater ability to utilize salt tolerance by keeping potassium levels high enough as to deny sodium uptake.
Removing sodium from the cytoplasm by means of sodium or hydrogen anti-porters is another mechanism to resist desiccation from high salinity environments by using the salt overly sensitive (SOS) regulation pathway. The SOS pathway exchanges excess sodium for hydrogen, and it is set into action by calcium signal flux.
Modifying the cytoskeleton or utilizing an osmotic stress pathway are two other physiological defenses plants use to handle salinity. The ability to sense excess salinity is a valuable tool, where excess sodium can trigger an influx of calcium and reactive oxygen species (ROS). Without the ability to notice sodium, calcium wouldn't be triggered into a signaling cascade to flow into the cytosol. This flow notifies the system to block salt ions from entering into the roots by using any available defenses, such as modifying the cell wall. A plant without these sensing and signaling capabilities is considered salt-sensitive, known as a glycophyte.
Metal toxicity
Metal pollution in soil will induce high toxicity in hemp plants. Cadmium (Cd) toxicity has been proven to be long term and irreversible in plants. Cd specifically results in oxidative stress and increase in free radicals. Free radicals are found to cause oxidative stress, cell damage, and death. Hemp plants in Cd polluted soils were found to help detoxify the metal while the plants were still conserved. While growth in these hemp plants were slightly reduced when planted in Cd concentration soil, continued plant growth indicated hemp plants were able to detoxify some Cd. Specifically, transporter proteins would move Cd into the cell wall and differentially expressed genes (DEGs) would activate, bind, and defend against Cd stress. These DEGs were found to be involved in cell wall metabolism and were most active when in contact with Cd. The plant hormone ABA plays an important role in activating signal transduction cascades and cell cycling and growth. An increase of ABC transporters in hemp plants contributes to increases in calcium concentration, indicating that calcium-binding proteins can control Cd concentration and absorption.
References
Cannabis
Chemical ecology | Chemical defenses in Cannabis | [
"Chemistry",
"Biology"
] | 2,686 | [
"Biochemistry",
"Chemical ecology"
] |
70,796,670 | https://en.wikipedia.org/wiki/Didymocyrtis%20trassii | Didymocyrtis trassii is a species of lichenicolous (lichen-eating) fungus in the family Phaeosphaeriaceae. It is found in southern Ukraine, where it parasitises the foliose lichen Cetraria aculeata growing on sand dunes.
Taxonomy
The fungus was formally described as a new species in 2018 by Ave Suija, Valeriy Darmostuk, and Alexander Khodosovtsev. The type specimen was collected by the third author between the between villages of Burkuty and Prominin in Hola Prystan Raion (Kherson Oblast); there, it was found growing on the foliose lichen Cetraria aculeata, which itself was growing in sand dunes. The species epithet honours Estonian lichenologist and botanist Hans Trass,
Description
Didymocyrtis trassii has pycnidial conidiomata of the Phoma-type. The pycnidia are black and more or less spherical, and partially immersed in the host thallus. They are typically 70–100 μm in diameter, with a wall that is 25–35 μm thick. The conidia are 14.2–18.2 by 5.0–7.2 μm. A sexual stage for the fungus is not known.
Habitat and distribution
Didymocyrtis trassii is only known to occur in southern Ukraine, and it only parasitises Cetraria aculeata growing on sand. The fungus grows on the lower branches of the thick cushions of the lichen, and does not appear to cause damage to the host.
References
Phaeosphaeriaceae
Fungi described in 2018
Fungi of Europe
Lichenicolous fungi
Taxa named by Ave Suija
Fungus species | Didymocyrtis trassii | [
"Biology"
] | 368 | [
"Fungi",
"Fungus species"
] |
70,797,458 | https://en.wikipedia.org/wiki/Line%20of%20sight | The line of sight, also known as visual axis or sightline (also sight line), is an imaginary line between a viewer/observer/spectator's eye(s) and a subject of interest, or their relative direction. The subject may be any definable object taken note of or to be taken note of by the observer, at any distance more than least distance of distinct vision. In optics, refraction of a ray due to use of lenses can cause distortion. Shadows, patterns and movement can also influence line of sight interpretation (as in optical illusions).
The term "line" typically presumes that the light by which the observed object is seen travels as a straight ray, which is sometimes not the case as light can take a curved/angulated path when reflected from a mirror, refracted by a lens or density changes in the traversed media, or deflected by a gravitational field. Fields of study feature specific targets, such as vessels in navigation, marker flags or natural features in surveying, celestial objects in astronomy, and so on. To have optimal observational outcome, it is preferable to have a completely unobstructed sightline.
Applications
Sightline (architecture)
Line-of-sight fire, shooting directly at a visible target on a relatively flat trajectory. The target is in the line of sight of the sighting device and the rifleman's rule applies.
Line-of-sight range
Line-of-sight (missile), the straight line between the missile and the target
Radar horizon
Line-of-sight propagation, electro-magnetic waves travelling in a straight line
Non-line-of-sight propagation
Line-of-sight velocity, an object's speed straight towards or away from an observer
Line-of-sight double star, one in which two stars are only coincidentally close together as seen from Earth
Beyond visual line of sight
References
Geometry
Line (geometry)
Vision | Line of sight | [
"Mathematics"
] | 389 | [
"Line (geometry)",
"Geometry"
] |
70,797,998 | https://en.wikipedia.org/wiki/Wolfgang%20Lechner | Wolfgang Lechner (born 14 May 1981 in Kufstein) is a theoretical physicist from Austria. He is the co-founder and co-CEO of the company ParityQC (Parity Quantum Computing GmbH) and professor at the Institute for Theoretical Physics of the University of Innsbruck.
Academic career
Wolfgang Lechner earned his Masters and PhD in Physics from the University of Vienna with Christoph Dellago as supervisor. He completed postdoctoral study under the direction of Peter Bolhuis at the University of Amsterdam from 2009 to 2011, followed by postdoctoral stints with Peter Zoller at IQOQI Innsbruck from 2011 to 2013 and at IQOQI Innsbruck from 2013 to 2016. Since December 2020 he is an associate professor at the Institute for Theoretical Physics, University of Innsbruck.
Research
Together with his colleagues Philipp Hauke and Peter Zoller, Wolfgang Lechner developed a quantum computing scheme which mitigates the fundamental connectivity limitations of quantum computers and solves general optimization problems through a software architecture. In 2017, Lechner set up a research team in the field of quantum optimization at the University of Innsbruck. The research group is dedicated to theoretical quantum physics, with the aim to solve computationally challenging problems efficiently in near term quantum devices. The research group published several papers including “Quantum Approximate Optimization With Parallelizable Gates” and “Quantum Optimization via Four-Body Rydberg Gates”.
ParityQC
In January 2020 Wolfgang Lechner co-founded the company ParityQC together with Magdalena Hauser, as a spin-off from the University of Innsbruck, and with Hermann Hauser as mentor. ParityQC is a quantum architecture company that develops blueprints for quantum computers to solve optimization problems as well as the appertaining operating system called ParityOS. The ParityQC architecture is a generalisation of the LHZ architecture for both digital and analog quantum devices.
Awards
Wolfgang Lechner has received a number of awards for his contributions to the field of quantum optimization. He was awarded the 2011 Loschmidt Prize of Austria's Chemisch Physikalische Gesellschaft, the 2015 Wallnöfer Prize of the Austrian Industrialists Association (IV), the 2017 Thirring Prize of the Austrian Academy of Sciences and the 2017 START Prize of the Austrian Science Fund. Lechner also received the Houska Prize 2019 which was awarded jointly to him and his research group, the Google Faculty Research Award for Quantum Computing, the 2020 “Spinoff Prize” Nature Research Award for ParityQC. In 2020, he was nominated among the “22 Innovators Building a Better Future” by Wired UK.
References
1981 births
Living people
21st-century Austrian physicists
People from Kufstein
University of Vienna alumni
Theoretical physicists
Academic staff of the University of Innsbruck | Wolfgang Lechner | [
"Physics"
] | 563 | [
"Theoretical physics",
"Theoretical physicists"
] |
70,798,598 | https://en.wikipedia.org/wiki/Aurantimycin%20A | Aurantimycin A is a depsipeptide antibiotic with the molecular formula C38H64N8O14. Aurantimycin A is produced by the bacterium Streptomyces aurantiacus. Aurantimycin A also show cytotoxic properties.
References
Further reading
Antibiotics
Depsipeptides
Cyclic peptides | Aurantimycin A | [
"Chemistry",
"Biology"
] | 75 | [
"Biotechnology products",
"Organic compounds",
"Antibiotics",
"Biocides",
"Organic compound stubs",
"Organic chemistry stubs"
] |
70,798,785 | https://en.wikipedia.org/wiki/List%20of%20Red%20Lists | This list is of Red Lists, Red Data Books, and related initiatives that assess and document the extinction risk of species, whether on an international or more local level (regional Red Lists). The IUCN has published a set of Guidelines for Application of the IUCN Red List Criteria at Regional and National Levels and at least 113 countries have produced their own Red Lists. Below, where a particular article or set of articles on a foreign-language Wikipedia provides fuller coverage, a link is provided.
International
International Union for Conservation of Nature
IUCN Red List
European Red List
Angola
: Lista Vermelha de Espécies de Angola, published by the Ministério do Ambiente
Armenia
: ԿԱՐՄԻՐ ԳԻՐՔ, published by the Ministry of Environment;
Australia
: Species Profile and Threats Database, published by the Department of Agriculture, Water and the Environment
Azerbaijan
:
Belarus
:
Brazil
: Livro Vermelho da Fauna Brasileira Ameaçada de Extinção, published by the Chico Mendes Institute for Biodiversity Conservation
Bulgaria
: Червена книга на Република България (Red Data Book of the Republic of Bulgaria), published by the Bulgarian Academy of Sciences and Ministry of Environment and Water;
Canada
: Species at risk public registry, published by the Government of Canada
China
: 中国生物多样性红色名录, published by the Ministry of Ecology and Environment: 脊椎动物卷 (vertebrates) 高等植物卷 (higher plants); 中国生物多样性红色名录 脊椎动物 第一卷 哺乳动物 (Mammals); cf.
Colombia
: Libros Rojos, published by the Ministry of Environment and Sustainable Development
Czech Republic
: Červené seznamy, published by the ;
Denmark
: Den danske Rødliste, published by Aarhus University;
Finland
: Suomen lajien uhanalaisuus – Punainen kirja, jointly published by the Ministry of the Environment; Web Service of the Red List of Finnish Species, published on the
France
: La Liste rouge des espèces menacées en France; , published by the National Museum of Natural History
Germany
:
Greece
: Το Κόκκινο Βιβλίο των Απειλούμενων Ζώων της Ελλάδας, published by the Hellenic Zoological Society;
Iceland
: Válistar published by the ;
Italy
: Liste Rosse Nazionali, published by the Ministry of the Ecological Transition
Japan
: Ministry of the Environment Red List
Kazakhstan
:
Kyrgyzstan
: Кыргыз Республикасынын Кызыл китеби;
Latvia
:
Lithuania
:
Moldova
: Cartea roșie a Republicii Moldova, published by the Academy of Sciences of Moldova and Ministry of Environment;
Netherlands
:
New Zealand
: New Zealand Threat Classification System, published by the Department of Conservation
Nicaragua
: Lista Roja, Especies en Alto Riesgo
Norway
: Norsk rødliste for arter, published by Artsdatabanken;
Philippines
: National List of Threatened Fauna, maintained by the Department of Environment and Natural Resources
Poland
: Polska Czerwona Księga Zwierząt; Polska Czerwona Księga Roślin;
Russia
: Red Data Book of the Russian Federation; also by Federal subject — Sakhalin Oblast: Красная Книга Сахалинской области: Животные / Растения и грибы; Category:Красные книги по субъектам Российской Федерации
South Africa
: Red List of South African Plants, published by the South African National Biodiversity Institute.
South Korea
: 한국의 멸종위기 야생동·식물 적색자료집, published by the Ministry of Environment and (Red Data Book 1 = Birds 조류, 2 = Amphibians and Reptiles 양서류·파충류, 3 = Fish 어류, 4 = Mammals 포유동물, 5 = Vascular Plants 관속식물);
Spain
: Libro rojo de los vertebrados de España, Atlas y libro rojo de la flora vascular amenazada de España, published by the Ministry of Environment
Sri Lanka
: The National Red List 2012 of Sri Lanka, published by the Ministry of Environment
Sweden
: Rödlistade arter i Sverige, published by the Swedish University of Agricultural Sciences (SLU Artdatabanken)
Switzerland
: Rote Listen: Gefährdete Arten der Schweiz, published by the Federal Office for the Environment; cf.
Taiwan
: 紅皮書名錄, published by the and Forestry Bureau; (Red List 1 = birds 臺灣鳥類紅皮書名錄, 2 = terrestrial reptiles 臺灣陸域爬行類紅皮書名錄, 3 = amphibians 臺灣兩棲類紅皮書名錄, 4 = freshwater fishes 臺灣淡水魚類紅皮書名錄, 5 = terrestrial mammals 臺灣陸域哺乳類紅皮書名錄, 6 = vascular plants 臺灣維管束植物紅皮書名錄)
Tajikistan
:
Turkmenistan
: Türkmenistanyň Gyzyl Kitaby, published by the Ministry of Nature Protection;
Ukraine
: Red Data Book of Ukraine
United Kingdom
: Conservation designations for UK taxa, published by the JNCC
United States of America
: Federal Lists of Endangered and Threatened Wildlife and Plants, published by the United States Fish and Wildlife Service
Uzbekistan
: O'zbekiston Respublikasining Qizil kitobi;
Vietnam
: Vietnam's Red Data Book
See also
List of heritage registers
References
External links
IUCN Regional Guidelines
National Red List database
Red Lists | List of Red Lists | [
"Biology"
] | 1,299 | [
"Bioinformatics",
"Biota by conservation status",
"Biological databases",
"Biota by conservation status system"
] |
70,799,034 | https://en.wikipedia.org/wiki/CyborgNest | CyborgNest Ltd is a company headquartered in London, United Kingdom. The start-up was the first in the world to commercialise sensory enhancement technology and created a wearable which used haptic technology (vibrations) to convey information to the wearer called NorthSense. The device was released in 2017 to connect wearers to the Earth's magnetic field.
NorthSense
In 2017 CyborgNest released the NorthSense, a miniaturized circuit board with over 200 components, with a silicone sleeve. The device was attached to the wearer's chest via steel piercings, and indicated when the wearer faced magnetic north, via a vibration. The device was inspired by a previous wearable called NorthPaw created by Sensebridge. It is unclear whether humans do, or did, possess this sense,
The device was made in a production batch of 400 units. NorthSense was documented in some technology articles.
The technology follows the principles of Sensory Substitution Devices (SSD), created by neuroscientist Paul Bach-y-Rita in the 1960s. SSDs are devices which translate one sense into another in order to compensate for an impaired sense. NorthSense also builds on the research of other similar haptics devices, such as the naviBelt (previously feelspace belt), which gives directional information through haptic motors around the wearer's waist. NorthSense was created using SSD principles but as a non-therapeutic device (not for medical use), transmitting non-human sensory information (the Earth's magnetic field), and therefore it is categorised as a ‘sensory augmentation’ technology.
Sentero
CyborgNest ran an Indiegogo crowdfunding campaign for the Sentero (presale) in July 2020 where crowdfunders raised approximately £50,000. Sentero was allegedly delivered to 50 of its crowdfunders, however it was never officially released and production has been cancelled. Backers were offered a refund.
Like the NorthSense, Sentero claimed that it would allow wearers to haptically feel the Earth's magnetic field (North), and also added the ability to 'sense' the direction of places and people, and feel their heartbeat.
See also
Sensory Substitution
Human Enhancement
Body Hacking
Neil Harbisson
Moon Ribas
Posthumanism
Extended Mind
References
Transhumanism
Electronics companies established in 2017
Biotechnology companies established in 2017
Biotechnology companies of the United Kingdom
Electronics companies of the United Kingdom
Privately held companies of the United Kingdom
Bionics
Neurotechnology | CyborgNest | [
"Technology",
"Engineering",
"Biology"
] | 529 | [
"Bionics",
"Genetic engineering",
"Transhumanism",
"Ethics of science and technology"
] |
70,799,651 | https://en.wikipedia.org/wiki/Texas%20House%20Bill%2020 | An Act Relating to censorship of or certain other interference with digital expression, including expression on social media platforms or through electronic mail messages, also known as Texas House Bill 20 (HB20), is a Texas anti-deplatforming law enacted on September 9, 2021.
It prohibits large social media platforms from removing, moderating, or labeling posts made by users in the state of Texas based on their "viewpoints", unless considered illegal under federal law or otherwise falling into exempted categories. It also requires them to make various public disclosures relating to their business practices (including the impact of algorithmic and moderation decisions on the content that is delivered to users).
The bill is part of a wider array of Republican-backed legislation seeking to prohibit the censorship of political speech, based on allegations that the moderation policies of large social media platforms are not politically neutral.
It has been challenged in NetChoice, LLC v. Paxton, and is currently the subject of a circuit split between the Fifth Circuit, and a decision by the Eleventh Circuit that struck down a similar bill in the state of Florida. In September 2023, the U.S. Supreme Court agreed to hear NetChoice v. Paxton jointly with NetChoice v. Moody on questions of whether the Florida and Texas state laws are in compliance with the 1st Amendment.
Content
The law applies to "social media platforms" that serve users in the state of Texas, and have more than 50 million monthly active users in the United States. They are defined as any public internet website or application that allows users to "communicate with other users for the primary purpose of posting information, comments, messages, or images", excluding internet service providers, electronic mail, and services where communication features are "incidental to, directly related to, or dependent on" content that is pre-selected by the operator. In the bill, to "censor" is defined as to "block, ban, remove, deplatform, demonetize, de-boost, restrict, deny equal access or visibility to, or otherwise discriminate against" expression.
The law prohibits social media platforms from "censoring on the basis of user viewpoint, user expression, or the ability of a user to receive the expression of others", or on the basis of a user's geographic location in Texas. This includes removal or labeling posts with warnings and disclaimers. Social media platforms may only censor content if it is unlawful, they are "specifically authorized" to do so by federal law, based on requests from "an organization with the purpose of preventing the sexual exploitation of children or protecting survivors of sexual abuse from ongoing harassment", or "directly incites" criminal activity or contains threats of violence against persons based on protected categories. It is disputed over whether this provision is actually enforceable, as it may be preempted by Section 230 of the Communications Decency Act (which states that the operators of interactive computer services are not responsible for the actions of their users).
Social media platforms must make public disclosures regarding the algorithmic techniques and moderation polices that are used to determine the content provided to users, must publish a compliant acceptable use policy (AUP), and must publish a biannual transparency report containing specific details on all actions made by the service regarding the moderation of users and content.
The law also prohibits email providers from "intentionally imped[ing] the transmission of another person's electronic mail message based on the content."
Legislative history
Texas Governor Greg Abbott signed the bill into law on September 9, 2021. Democrat-proposed amendments excluding Holocaust denial, terrorism content, and vaccine misinformation from the bill were rejected.
Following a suit by the industry groups Computer & Communications Industry Association (CCIA) and NetChoice, NetChoice, LLC v. Paxton, the bill was blocked by U.S. District Judge Robert Pitman in December 2021, on First Amendment grounds. Texas appealed to the United States Court of Appeals for the Fifth Circuit. Judges Edith Jones, Andrew Oldham, and Leslie H. Southwick, lifted the injunction on May 11, 2022, but the decision was appealed to the Supreme Court which suspended the bill pending a full review in the Fifth Circuit.
On September 16, 2022, the Fifth Circuit reversed the injunction, allowing the bill to take effect; Judge Oldham stated that the bill "chills censorship" and "does not chill speech", and accused the plaintiffs of "attempt[ing] to extract a freewheeling censorship right from the Constitution's free speech guarantee. The Platforms are not newspapers. Their censorship is not speech." Southwick dissented, stating that "we are in a new arena, a very extensive one, for speakers and for those who would moderate their speech. None of the precedents fit seamlessly." The CCIA and NetChoice requested a stay on the ruling and that the case be taken to the Supreme Court, arguing that the reversal conflicts with an Eleventh Circuit decision in NetChoice v. Moody which struck down a similar anti-moderation bill imposed by the state of Florida. On October 12, 2022, the Fifth Circuit granted the stay.
References
External links
Texas Legislature Online
Legiscan
Texas statutes
2022 in Texas
2021 in Texas
Internet censorship in the United States | Texas House Bill 20 | [
"Technology"
] | 1,085 | [
"Computing and society",
"Social media"
] |
70,800,230 | https://en.wikipedia.org/wiki/Felix%20Boehm | Felix Hans Boehm (June 9, 1924, Basel – May 25, 2021, Altadena, California) was a Swiss-American experimental physicist, known for his research on weak interactions, parity violation, and neutrino physics.
Biography
He had four brothers and both his father and his paternal grandfather were in the publishing business. Felix Boehm completed his Matura in 1943 and was drafted into Swiss army, which allowed him to study physics part-time at the University of Geneva. In the autumn of 1943 he matriculated at ETH Zurich. There he took several classes from Wolfgang Pauli and graduated in physics with his Diplom in 1948 and his doctorate in 1951 with doctoral advisor Paul Scherrer. Boehm worked as an assistant to Scherrer from 1951 to March 1952 and then went as a Boese Fellow to Columbia University, where he studied with C. S. Wu for a year and a half. As a postdoctoral research fellow he went in July 1953 to Caltech, where he studied with Jesse DuMond and Charles Lauritsen. In 1957 Boehm married Ruth Sommerhalder, whom he met in 1956 at a social occasion at the Swiss consulate in Los Angeles. At Caltech he became in 1958 an assistant professor, in 1961 a full professor at Caltech, in 1985 William L. Valentine Professor of Physics, and in 1995 professor emeritus in retirement. In 1960 he played an essential role in bringing Rudolf Mössbauer to the California Institute of Technology. In 1961 Boehm was awarded a 2-year Sloan Research Fellowship.
He held visiting positions in 1957/58 at the University of Heidelberg (at the invitation of Jensen), 1965/66 at the University of Copenhagen, in 1971/72 at CERN, and in 1979/80 at the Institut Laue-Langevin in Grenoble, where he also worked with scientists from the Paul Scherrer Institute. He was a visiting professor in 1980 at the Ludwig Maximilian University of Munich and 1981 at ETH Zurich. (Years earlier he had turned down an offer of a professorship at ETH in favor of Caltech.)
In the 1950s Boehm worked on experiments on parity violation and experimentally confirmed the violation first reported by C. S. Wu. In 1956 Boehm and Aaldert Wapstra made the confirmation by measuring the circular polarization of gamma rays in beta decay. At Caltech Boehm came into contact with the theorists Richard Feynman and Murray Gell-Mann. Boehm did research on X-ray spectroscopy in nuclear physics, specifically, isotope shift of K-shell electrons and then experiments involving muons at CERN and at the Los Alamos Meson Physics Facility (LAMPF). He collaborated with French and Swiss scientists on neutrino detection with an experiment set up in the Gotthard Tunnel. For a number of years, he and his group also searched in vain for violations of time reversal invariance in nuclear physics (but found upper bounds for such violations). At Caltech he did research on double beta decay. In 1969 and 1970 he and J. C. Vanderleeden found parity non-conservation in nuclear forces by measuring the circular polarization of gamma rays from unpolarized atomic nuclei. Beginning in 1970 he collaborated extensively with the theorist Petr Vogel.
In 1980 Boehm received the Humboldt Research Award. In 1983 he was elected a member of the National Academy of Sciences.
In 1995 he received the Tom W. Bonner Prize in Nuclear Physics with citation:
In 2006 he was elected a Fellow of the American Association for the Advancement of Science.
Upon his death in 2021 he was survived by his widow and their two sons.
Selected publications
Articles
Books
1st edition 1988
References
1924 births
2021 deaths
20th-century American physicists
20th-century Swiss physicists
ETH Zurich alumni
California Institute of Technology faculty
Scientists from Basel-Stadt
Experimental physicists
Nuclear physicists
Members of the United States National Academy of Sciences
Fellows of the American Association for the Advancement of Science
Swiss emigrants to the United States
People associated with CERN | Felix Boehm | [
"Physics"
] | 835 | [
"Experimental physics",
"Experimental physicists"
] |
70,800,665 | https://en.wikipedia.org/wiki/Neodymium%28III%29%20perchlorate | Neodymium(III) perchlorate is an inorganic compound. It is a salt of neodymium and perchloric acid with the chemical formula of Nd(ClO4)3 – it is soluble in water, forming purple-pink, hydrated crystals.
Properties
Physical properties
Neodymium(III) perchlorate forms pale purple crystals when in its anhydrous form.
It is soluble in water.
It forms crystals Nd(ClO4)3·nH2O, where n = 4, 4.5 are purple-pink crystals, and n = 6 forms pale pink to lavender crystals.
Alkaline salts
Nd(ClO4)3 can form alkaline salts, with the general formula of Nd(OH)x(ClO4)3 − x. The salt with x = 1.5 (saturated with 5 water atoms) is a light purple crystal with d = 2.88 g/cm³.
Other compounds
Nd(ClO4)3 can form compounds with hydrazine, such as Nd(ClO4)3·6N2H4·4H2O which is a small white crystal that is soluble in water, methanol, ethanol and acetone, and insoluble in toluene, with density of 2,3271 g/cm³ at 20 °C.
References
Perchlorates
Neodymium(III) compounds | Neodymium(III) perchlorate | [
"Chemistry"
] | 295 | [
"Perchlorates",
"Salts"
] |
70,800,747 | https://en.wikipedia.org/wiki/Women%20Divers%20Hall%20of%20Fame | The Women Divers Hall of Fame (WDHOF) is an international honor society. Its purpose is to honor the accomplishments of women divers, and their contributions to various fields of underwater diving. Full membership is restricted to nominees who have been found to meet the WDHOF's criteria, which include being an underwater diver and having contributed to diving in ways recognised as being significant.
History
The WDHOF was founded in 1999 by a group of people and organizations, including the Underwater Society of America. 72 women were inducted in 2000, followed by 26 new members the next year.
Scholarships and grants
The WDHOF awards many scholarships and training grants to support women of "all ages who are pursuing careers involving diving" including the J. Berman Memorial Grant for Sea Turtle Conservation, the Sherry Reed Memorial Undergraduate Marine Conservation Scholarship, the Laurel Clark Sea to Space Physiology Research Grant and the Amelia Behrens-Furniss Memorial Hardhat Dive Training Grant.
Members
As of 2023, there are 254 members. They include:
References
External links
Women Divers Hall of Fame Introduction V2, WDHOF video
Underwater diving lists
Sports halls of fame
Science and technology halls of fame
Honor societies
Women Divers Hall of Fame
Women's halls of fame | Women Divers Hall of Fame | [
"Technology"
] | 248 | [
"Science and technology awards",
"Science and technology halls of fame"
] |
70,801,467 | https://en.wikipedia.org/wiki/Entoloma%20medianox | Entoloma medianox is a species of agaric (gilled mushroom) in the family Entolomataceae. It is known from western North America, where it was previously referred to the European species Entoloma bloxamii or E. madidum. Molecular research, based on cladistic analysis of DNA sequences, has, however, shown that Entoloma medianox is distinct.
Description
The fungus produces a striking, blue, mushroom-shaped fruiting body (basidiocarp), between August and November. The smooth cap measures and has a broad swelling in the centre (known as a boss or umbo). The tightly packed, white gills on the underside of the cap contrast well with the blue colour of the fungus; they become more salmon-pink as they age. The solid stipe of the mushroom ranges from tall and 1–3 cm wide, and is also blue with a whitish base. The spore print is pink to cinnamon-coloured.
See also
List of Entoloma species
References
Fungi of North America
Fungi described in 2015
Entolomataceae
Fungus species | Entoloma medianox | [
"Biology"
] | 232 | [
"Fungi",
"Fungus species"
] |
70,801,978 | https://en.wikipedia.org/wiki/Epicoccum%20sorghinum | Epicoccum sorghinum (former Phoma sorghina) is an ascomycete fungus with known plant pathogenicity to sugarcane and rice, causing ring spot disease and leaf spot disease. This fungus is primarily known for its production of tenuazonic acid, which leads to complications with growth and causes the symptoms of leaf spot disease. Tenuazonic acid not only affects plant growth, but has recently been proven to impact human health due to its prevalence in food and beverages. It is widely dispersed, affecting multiple hosts in different countries. Although not a serious threat, Epicoccum sorghinum has been known to influence the sorghum grain-mold complex in ways which reduce crop yields, seed viability, and kernel weight. As a result of continuous phylogenetic and morphological discoveries relevant to Epicoccum sorghinum, this fungus has undergone a number of name changes.
Taxonomy
Throughout its known existence, Epicoccum sorghinum has possessed many names. Initially, Saccardo isolated the fungus from Sorghum vulgare and named it Phyllosticta sorghina. In 1973, Boerema, Dorenbosch, and Van Kesteren changed its name to Phoma sorghina, which is occasionally still utilized. In 2010, it was again renamed Epicoccum sorghi by Aveskamp and others, due to recent phylogenetic and morphological characteristics. Currently, Epicoccum sorghinum serves as the accepted name for this fungus.
Disease and hosts
A variety of fungal pathogens cause ring spot disease and leaf spot disease. The genus Epicoccum is ubiquitous and contains many species that are plant pathogenic. Epicoccum sorghinum commonly infects sugarcane, but recent discoveries have found that it can also use rice as its host. Epicoccum sorghinum is a fungal contaminant that can be isolated from a variety of cereals in sorghum grains. As a result, it contributes to the pathogenicity of the sorghum gain-mold complex. Less common diseases caused by Epicoccum sorghinum include root rot, dying-off, glume blotch, and glume blight, all of which affect various hosts.
Host symptoms
Leaf spot disease, the most common symptom of infection from Epicoccum sorghinum, causes small, chlorotic spots with gray/black centers and yellow halos. The spots initially appear at the bottom of the plant and slowly progress upwards. As a result of this weak progression of infection, the lower potion of the plant expresses significant damage while the upper portion may only have a few spots.
Tenuazonic acid
Tenuazonic acid is a mycotoxin produced by fungal pathogens like Epicoccum sorghinum. Production of this component causes inhibition of protein synthesis which leads to growth disorders of the plant.
Human impact
Metabolites produced by Epicoccum sorghinum have been known to impact human health, specifically causing erythematous lesions on the skin. This infection is not common and occurs primarily in immunocompromised individuals.
Distribution and habitat
Epicoccum sorghinum is typically found in tropical and subtropical regions of a variety of countries including Brazil, China, France, India, South Africa, Thailand, Turkey, United States, etc. Epicoccum sorghinum has also been known to inhabit temperate regions and grasses (gramineae).
Characteristics
On a medium, Epicoccum sorghinum produces a reddish/brown pigment. Colonies are 5-9 cm and circular in shape. The mycelium of Epicoccum sorghinum is dense and fluffy. The color of mycelium varies and can be gray, green, and salmon colored. Under a microscope, Epicoccum sorghinum produces brown or translucent, subglobose pycnidia with straight necks. Size varies from 67.9 to 117.5 x 44.5 to 90.1 micrometers. Chlamydospores are unicellular or multicellular, botryoid, and brown or translucent. Conidia are unicellular, oval shaped or curved, translucent (hyaline), and 3.6 to 5.3 x 1.8 to 2.8 micrometers.
Significance
Epicoccum sorghinum is currently not a significant threat to rice development, as there are two other fungal diseases of rice that are more common, rice blast and brown leaf spot. However, ring spot disease due to Epicoccum sorghinum on sugarcane has been known to significantly reduce stalk sugar yield. Sorghum is a frequently consumed grain that is negatively affected by toxins of fungi. As a result, disease of this genus can lead to decreased production and consumption which may impact certain countries economically. Environmental factors have been proven to influence the amount of tenuazonic acid produced by Epicoccum sorghinum. Specifically, the production of tenuazonic acid in grains is highest during the summer. Amongst the pathogenic effects of Epicoccum sorghinum, recent studies support ethyl acetate, a biologically active compound from E. sorghinum, as an antiplatelet aggregation and anti-inflammatory agent.
References
Pleosporales
Fungal plant pathogens and diseases
Fungus species | Epicoccum sorghinum | [
"Biology"
] | 1,101 | [
"Fungi",
"Fungus species"
] |
70,802,355 | https://en.wikipedia.org/wiki/Spectral%20dimension | The spectral dimension is a real-valued quantity that characterizes a spacetime geometry and topology. It characterizes a spread into space over time, e.g. an ink drop diffusing in a water glass or the evolution of a pandemic in a population. Its definition is as follow: if a phenomenon spreads as , with the time, then the spectral dimension is . The spectral dimension depends on the topology of the space, e.g., the distribution of neighbors in a population, and the diffusion rate.
In physics, the concept of spectral dimension is used, among other things, in
quantum gravity,
percolation theory,
superstring theory, or
quantum field theory.
Examples
The diffusion of ink in an isotropic homogeneous medium like still water evolves as , giving a spectral dimension of 3.
Ink in a 2D Sierpiński triangle diffuses following a more complicated path and thus more slowly, as , giving a spectral dimension of 1.3652.
See also
Dimension
Fractal dimension
Hausdorff dimension
References
Geometry
Diffusion
Quantum gravity
Power laws | Spectral dimension | [
"Physics",
"Chemistry",
"Mathematics"
] | 219 | [
"Transport phenomena",
"Physical phenomena",
"Diffusion",
"Unsolved problems in physics",
"Quantum gravity",
"Geometry",
"Physics beyond the Standard Model"
] |
70,802,892 | https://en.wikipedia.org/wiki/Nanostictis%20caucasica | Nanostictis caucasica is a species of lichenicolous (lichen-eating) fungus in the family Stictidaceae. It is known to occur only in a single locality in the North Caucasus region of Southern Russia, where it grows parasitically on the foliose lichen Parmelia sulcata.
Taxonomy
Nanostictis caucasica was formally described as a new species in 2017 by Russian lichenologist Mikhail Zhurbenko. The type specimen was collected from a northern spur of Gora Armovka, a mountain in Krasnodar Krai. There, at an altitude of , the fungus was found growing on the lobes of the foliose lichen Parmelia sulcata, which itself was growing on Betula litwinowii in a forest at the upper boundary of the mountain forest belt.
Description
The fungus produces cup-shaped apothecia that are 250–600 μm in diameter; they emerge through the thallus surface of the host until they are about half or more exposed. They have a dull white, persistent margin that is grainy due to the crystal depositions on the surface. The asci are somewhat cylindrical with a rounded tip, and typical dimensions of 67–86 by 8–10.5 μm. Most of the asci contain eight ascospores, although in rare instances they only have four. The ascospores are hyaline, usually have between 10 and 16 septa, and measure 53.7–73.7 by 3.0–3.8 μm.
The type species of genus Nanostictis, N. peltigerae, has a morphology that is similar to N. caucasica. They differ in microscopic characteristics, such as numbers of spores in the ascus, spore septation, and spore size.
References
Ostropales
Fungi described in 2017
Fungi of Europe
Lichenicolous fungi
Taxa named by Mikhail Petrovich Zhurbenko
Fungus species | Nanostictis caucasica | [
"Biology"
] | 410 | [
"Fungi",
"Fungus species"
] |
70,804,305 | https://en.wikipedia.org/wiki/Ambobactin | Ambobactin is an depsipeptide antibiotic with the molecular formula C59H77N13O19. Ambobactin is produced by the bacterium Streptomyces ambofaciens.
References
Antibiotics
Depsipeptides | Ambobactin | [
"Chemistry",
"Biology"
] | 58 | [
"Biotechnology products",
"Organic compounds",
"Antibiotics",
"Biocides",
"Organic compound stubs",
"Organic chemistry stubs"
] |
70,804,411 | https://en.wikipedia.org/wiki/Douglas%20Woodall | Douglas Robert Woodall (born November 1943 in Stoke-on-Trent) is a British mathematician and election scientist. He studied mathematics at the University of Cambridge and earned his Ph.D. from the University of Nottingham in 1969, his thesis being "Some results in combinatorial mathematics". He worked in the Department of Mathematics from 1969 until his retirement in 2007, as researcher, lecturer, associate professor and reader. He devised the later-no-harm criterion, a voting system criterion in the comparison of electoral systems, and demonstrated it is compatible with the monotonicity criterion by developing his method of descending solid coalitions as an improvement on instant-runoff voting. He also contributed to the problem of fair cake-cutting, for example, by presenting an algorithm for finding a super-proportional division.
Selected publications
See also
Woodall's conjecture on dicuts and dijoins in directed graphs
References
External links
1943 births
Living people
Psephologists
Voting theorists
Combinatorialists
British mathematicians
Alumni of the University of Cambridge
Alumni of the University of Nottingham
Academics of the University of Nottingham
People from Stoke-on-Trent
Fair division researchers | Douglas Woodall | [
"Mathematics"
] | 231 | [
"Combinatorialists",
"Combinatorics"
] |
70,804,519 | https://en.wikipedia.org/wiki/Gilvocarcin%20V | Gilvocarcin V is an antitumor agent and an antibiotic which is active against Gram-positive bacteria with the molecular formula C27H26O9. Gilvocarcin V is produced by the bacterium Streptomyces griseoflavus and other Streptomyces bacteria. Gilvocarcin V is a strong inhibitor of the DNA synthesis.
References
Further reading
DNA replication inhibitors
Antibiotics
Heterocyclic compounds with 4 rings
Lactones
Tetrahydrofurans
Methoxy compounds
Hydroxyarenes
Vinyl compounds | Gilvocarcin V | [
"Biology"
] | 113 | [
"Antibiotics",
"Biocides",
"Biotechnology products"
] |
72,274,405 | https://en.wikipedia.org/wiki/Water%20International | Water International is a peer-reviewed scientific journal covering research on water resources. It is the official journal of the International Water Resources Association and was established in 1972. The journal is published by Routledge in 8 issues per year and focuses on international water resources including science, technology, governance, management, and policy. The editor-in-chief is James E. Nickum (International Water Resources Association, Japan).
Abstracting and indexing
The journal is abstracted and indexed in:
According to the Journal Citation Reports, the journal has a 2021 impact factor of 3.395.
See also
Water Research
Water (journal)
Journal of Irrigation & Drainage Engineering
References
External links
Academic journals established in 1972
English-language journals
Routledge academic journals
Hydrology journals
8 times per year journals | Water International | [
"Environmental_science"
] | 154 | [
"Hydrology",
"Hydrology journals"
] |
72,275,301 | https://en.wikipedia.org/wiki/Hugh%20G.%20Robinson | Hugh Granville Robinson (August 4, 1932 - March 1, 2010) was the first African American general officer in the United States Army Corps of Engineers and a decorated veteran of the Vietnam War. Robinson served as the military aide to President Lyndon B. Johnson, the first African American to hold such a position.
Early life and education
Robinson was born on August 4, 1932, in Washington, D.C. His father, Colonel James H. Robinson, was a career Army officer. Robinson graduated from Dunbar High School and later attended the United States Military Academy. Upon graduating in 1954, Robinson was commissioned in the United States Army Corps of Engineers and attended the Massachusetts Institute of Technology where he earned a Master's Degree in Civil Engineering in 1959. He later completed the Harvard Business School Management Program for Executives and was awarded an honorary Doctor of Laws degree from Williams College.
Career
Military career
Robinson served in the military between 1954 and 1983. After a tour of duty in Korea and time holding various Army staff positions, Robinson worked for the deputy chief of staff for operations at The Pentagon. In 1965, President Lyndon B. Johnson appointed Robinson as his military aide. Robinson served in this position throughout the remaining duration of Johnson's term as President.
Upon leaving the White House, Robinson served in Vietnam as the deputy group commander of the 45th Engineer Group and as commander of the 39th Engineer Battalion. In recognition of his service, he received an Air Medal, a Bronze Star Medal, the Legion of Merit and a Commendation Medal.
Robinson returned to West Point in 1972 to serve as the 3rd Regimental Tactical officer, where he was tasked with developing and training cadets. He was later promoted to Colonel and then Brigadier General in 1978, in which he became the first African American general officer in the United States Army Corps of Engineers. He was again promoted in 1980 to Major General and was assigned the responsibility of commanding the Corps of Engineers' Southwestern Division. He held this position until his retirement from the military in 1983.
Post-military career
Following his time in the military, Robinson held various executive and corporate board positions. This included acting as Chief Executive Officer of the Tetra Group and Chief Operating Officer of Nova Energy. For seven years, Robinson served as vice chairman and then chairman of the Federal Reserve Bank of Dallas. Robinson was also involved in civic affairs, founder of the Dallas Youth Services Corps and co-chairman of Dallas Promise.
References
1932 births
2010 deaths
United States Army Corps of Engineers
Fellows of the American Physical Society | Hugh G. Robinson | [
"Engineering"
] | 498 | [
"Engineering units and formations",
"United States Army Corps of Engineers"
] |
72,275,452 | https://en.wikipedia.org/wiki/Alta%20Walker | Alta Walker (April 28, 1942 – August 1, 2015) also known as A.S. Walker was an American geologist for the National Air and Space Museum, the US Geological Survey, and Department of the Interior, where she mapped the moons of Jupiter as well as the dark side of Earth’s Moon. Walker participated in a National Academy of Sciences scientific study group in 1980 in China. Her research on desertification was featured in American Scientist with her article, “Deserts of China.”
According to her obituary, she was one of the first female Americans to be an astronaut candidate.
Walker authored several books on deserts, geology and resources between 1981 and 2000<, was a contributing writer of the book Geomorphology from Space and co-authored Rocks and War: Geology and the Civil War Campaign of Second Manassas with her partner E-An Zen.
Early life and education
Walker was from Ogdensburg, New York and her parents were William and Kathleen Walker and she graduated from Ogdensburg Free Academy in 1960. She went on to earn a Bachelor of Arts in English from Syracuse University, a Master of Arts in Earth Science from the University of Minnesota and a Doctor of Philosophy in Geochemistry from Rice University. Her doctoral dissertation was titled "Inert Gas Investigations of Five Apollo 11 and 12 Breccias and of an Apollo 17 Soil Sample".
References
External links
American Scientist Magazine, Volume 70
Geomorphology from Space
Rocks and War: Geology and the Civil War Campaign of Second Manassas
Inert Gas Investigations of Five Apollo 11 and 12 Breccias and of an Apollo 17 Soil Sample
1942 births
2015 deaths
People from Ogdensburg, New York
Syracuse University alumni
University of Minnesota alumni
Rice University alumni
American women geologists
American geologists
Women geochemists
Women science writers | Alta Walker | [
"Chemistry"
] | 364 | [
"Geochemists",
"Women geochemists"
] |
72,276,164 | https://en.wikipedia.org/wiki/Facilitation%20cascade | A facilitation cascade is a sequence of ecological interactions that occur when a species benefits a second species that in turn has a positive effect on a third species. These facilitative interactions can take the form of amelioration of environmental stress and/or provision of refuge from predation. Autogenic ecosystem engineering species, structural species, habitat-forming species, and foundation species are associated with the most commonly recognized examples of facilitation cascades, sometimes referred to as a habitat cascades. Facilitation generally is a much broader concept that includes all forms of positive interactions including pollination, seed dispersal, and co-evolved commensalism and mutualistic relationships, such as between cnidarian hosts and Symbiodinium in corals, and between algae and fungi in lichens. As such, facilitation cascades are widespread through all of the earth's major biomes with consistently positive effects on the abundance and biodiversity of associated organisms.
Overview
Facilitation cascades occur when prevalent foundation species, or less abundant but ecologically important keystone species, are involved in a hierarchy of positive interactions and consist of a primary facilitator which positively affects one or more secondary facilitators which support a suite of beneficiary species. Facilitation cascades at a minimum have a primary and secondary facilitator, although tertiary, quaternary, etc. facilitators may be found in some systems.
A typical example of facilitation cascades in a tropical coastal ecosystem
Origin of concept and related terms
The term facilitation cascade was coined by Altieri, Silliman, and Bertness during a study on New England cobblestone beaches to explain the chain of positive interactions that allow a diverse community to exist in a habitat that is otherwise characterized by substrate instability, elevated temperatures, and desiccation stress. Cordgrass is able to establish independently, and then creates a stable and less stressful habitat for mussels which in turn provide hard substrates and damp crevice spaces to facilitates establishment of a community of invertebrates and algal species. Facilitation cascades differ from the facilitation model of succession because species accumulate in the ecosystem due to the direct and indirect effects of the primary and secondary facilitator, whereas in the succession, early species that play a facilitative role are, over time, replaced by later-stage species. The concept emphasizes the hierarchical organization of nature, in which a foundation species creates the basis for an entire community by building a unique habitat, as seen in coral reefs, kelp beds, or hemlock forests, and then secondary interactions (e.g., competition, predation, facilitation) among inhabitants refine community composition and ecological dynamics. The facilitation cascade concept was also foreshadowed by the observation that multiple ecosystem engineers can interact to have emergent synergistic effects.
Facilitation cascades thus represent a form of indirect interaction occurring over three or more levels, whereby one species impacts another via an intermediate species. Such indirect interactions are an important driver of community structure and ecosystem function that can be as frequent and influential as direct interactions. Facilitation cascades have far-reaching ecological impacts on the diversity and function of the ecosystem as the positive effects of a subset of organisms cascade through the community, as in trophic cascades. The effect size of facilitation cascades can rival or exceed that of trophic cascades, and the main distinction between the indirect positive effects of both facilitation cascades and trophic cascades is that the former is based on positive facilitative interactions whereas the latter is based on negative trophic interactions.
Classic examples
Facilitation cascades are observed in all of earth's major ecosystem types, and representative examples illustrate their widespread importance as well as the diversity of cascades that arise. The significance of facilitation cascades is often apparent through direct observation, however, experimental manipulations with mimics offer strong evidence for the magnitude of interaction importance. For examples, using artificial mimics as replacements for primary and secondary foundation species allows for isolation of specific mechanisms that are hypothesized to underlie the cascading effects of facilitation on local ecosystem dynamics.
Marine
A classic example of facilitation cascades in the marine environment is the relationship between mangroves, seagrasses, and stony corals that are adjacent to one another in a seascape. These foundation species exchange resources and benefit each other by buffering against sedimentation and nutrient inputs from the terrestrial side, and reducing wave energy from the open ocean. This exemplifies how facilitation cascades can occur over a seascape through foundation species that are found adjacent to one another.
Another common example in marine ecosystems is where seagrass, a primary habitat-forming ecosystem engineer, facilitates bivalves such as mussels by providing them with refuge from predators and stable attachment substrate. In turn, the bivalves act as secondary habitat formers, facilitating epifaunal organisms by providing them with substrate to attach and settle. Since the bivalves can provide nutrient subsidies to the seagrass, this is an example of a common structure of facilitation cascades where the secondary facilitators have a positive effect on primary facilitators, such that there is mutualism within the cascade.
Transitional (intertidal)
On the cobblestone beaches of New England, cordgrasse ameliorates physical stress for the establishment of ribbed mussels which further facilitating increased diversity within the intertidal ecosystem as secondary foundation species. This is the interaction from which the facilitation cascade concept was formed. This complex habitat has also shown how facilitation cascades can increases invasibility because non-native crabs live on and among ribbed mussels, providing a mechanisms to explain positive relationships between native diversity and invasion success, and the co-existence of native and invasive species through differential use of microhabitats associated with the cascade. In salt marshes, the same species of cordgrass and mussels have also been shown to increase biodiversity, multifunctionality, and resilience to disturbance.
Oyster reefs stabilize the intertidal environment by reducing sediment erosion. This enhances growth of marsh grasses which act as secondary foundation species, facilitating invertebrates including bivalves, insects and birds. The places with oyster reefs and intertidal marshes have been observed to support a higher biodiversity and abundance of inhabitants compared to sites inhabited by only one of those foundation species.
Mangrove forests along the coast of Australia trap drifting seaweed among their pneumatophores, which this seaweed supports many mollusks through habitat creation and shelter from predation. This example is notable because it involves a foundation species (mangroves) increasing their facilitative effect by aggregating a drifting secondary species from nearby rocky reefs.
Another example in transitional environments includes the facilitation of seaweed assemblages in soft-bottom shallow lagoons by gardening tube forming polychaetes that actively incorporate seaweed fragments to reduce predation and increase food-supply. The seaweed subsequently provides habitats and supports the high diversity of small epiphytes, invertebrates, and fish in an otherwise bare soft sediment system. This example is notable because the secondary habitat-forming seaweed is invasive in this region.
Terrestrial
A classic example of a terrestrial facilitation cascade includes tropical rainforest trees as the facilitating epiphytes which in turn facilitate the abundance of inhabitant invertebrate species by providing a complex, diverse habitat. For example, about half of the invertebrate biomass and abundance of invertebrates was observed to be dependent on secondary epiphyte habitats, suggesting that early estimates of the notably high arthropod diversity in tropical forests may in part be driven by facilitation cascades. This example is notable due to the different taxonomic composition and larger size of insects found in the secondary, intermediate habitat when compared with that of the primary foundation tree species representing the basal habitat. In temperate forests, a similar cascade unfolds in which facilitation of Spanish moss by oak trees increases invertebrate diversity. In this example, the Spanish moss depend on the oak to reduce physical stress and the invertebrates are reliant on the Spanish moss to increase moisture and lower predation stress.
Another terrestrial facilitation cascade includes trees, mistletoe, and birds, where trees are the primary foundation species that facilitates mistletoe, a secondary foundation species, which then facilitates the nesting and feeding of local and migratory birds. This example has been observed in multiple places around the world from pine forests in southeastern Spain to semi-arid southeastern Zimbabwean savannas. The example is notable because mistletoes can be parasitic and have a negative effect on their tree hosts, which is a reminder that the direction and strength of interactions associated with facilitation cascades can be context-dependent.
Freshwater
A classic freshwater facilitation cascade includes freshwater plants facilitating growth of algal filaments which in turn facilitate snails. Here, the plants act as primary foundation species, while the algal filaments, attached by plant holdfasts, are secondary foundation species, facilitating the snail inhabitant. This example is significant due to the chemical signals sent from secondary foundation species to attract the diversity of inhabitant snail to the cascade habitat.
However, only a few studies appear to have documented freshwater facilitation cascades, and it remains to be determined whether this is a function of the ecosystem structure or simply a reflection of historic research perspectives.
Scale and ecological feedbacks
Spatial configuration
The primary and secondary foundation species that make up a facilitation cascade can occur in one of two spatial configurations. First are nested configurations in which the two foundation species are found intermixed or with one facilitator living on another, as in a mangrove pneumatophore providing a surface for oyster colonization. Second are adjacent configurations in which the facilitative species are found segregated across the landscape, as in oyster reefs near salt marshes, or coral reefs adjacent to seagrass. Whether foundation species in a cascade are found in adjacent or nested configurations depends on whether competition for resources at some scale drives one foundation species to displace another. The stress gradient hypothesis has proven useful for predicting which configuration is likely to prevail. In some instances there is scale dependence of the interactions, where competition over short distances leads to zonation of foundation species with distinct borders, and facilitation over longer distances occurs between the organisms in these zones. Facilitation cascades can also be structured as patches on the landscape that arise either because a primary and secondary habitat-forming species co-occur in patches, or a secondary habitat-former exists in patches within a large continuous habitat created by the primary habitat-former.
Temporal variation
The strength of facilitation cascades can also vary across temporal scales. Spatial scale can be influenced by how rapidly a foundation species grows or reproduces, as well as how long the effect of facilitation takes to impact other species within the system. This can be due to the time necessary for a foundation species to reach a minimum individual or patch size to create a facilitative effect for the system, lags in the demographic response in the beneficiary species to the positive effects of a facilitator, or seasonality or some other temporal variability in the stress that the facilitator ameliorates. Phenological matching or mismatching of life cycles may also influence the co-occurrence of participants in a facilitation cascade and therefore the strength of their interaction. For example, hatching of insects that coincides with flowering of the plants they pollinate which are in turn used as habitat for other species later in that year.
Dispersal and movement
Movement of organisms can mediate the occurrence and importance of facilitation cascades in three ways. First, movement of a facilitative species to a location with another facilitative species can bring together the components for a facilitation cascade. For examples, algae from a rocky shore that drifts into mangrove root habitat together can facilitate a variety of mobile invertebrates. Second, species that benefit from a facilitation cascade may move beyond the cascade habitat (i.e., spillover) and play an ecologically important role in adjacent habitats. On cobble beaches, for example, an invasive shore crabs utilizes a cordgrass-mussel facilitation cascade as a nursery habitat, but then as adults move into adjacent unvegetated intertidal habitats where they compete with native mud crabs. For highly mobile beneficiary species, such as those with more distant ontogenetic habitat shifts, large foraging ranges, or the capability of long-distance migrations, the reach of the facilitation cascade may be quite extensive. Third, mobile organisms may serve as a facilitative link in a cascade that plays across habitats distantly located on a landscape, as in mangroves that may facilitate coral reefs through the movement of parrotfish that use the mangrove as a nursery habitat and then move to a coral reef where they graze nuisance algae that would otherwise smother corals. More generally, these movements of individuals can serve as a biogeochemical or trophic link between ecosystems, leading to nutrient subsidies and feedbacks that sustain the foundation species that form the basis of facilitation cascades and providing the basis for meta-ecosystems.
Ecological significance
Biodiversity
Facilitation cascades have strong positive effects on biodiversity at local or patch scale via direct and indirect facilitation. Within a facilitation cascade, primary and secondary foundation can increase organismal survival, species richness, niche diversity, and habitat complexity, in turn enhancing biodiversity. Primary habitat-formers can provide suitable substrate for colonization by secondary habitat-formers unique traits that contribute to increased heterogeneity enhancement of biodiversity.
Ecosystem functioning
Given the close relationship between biodiversity and ecosystem function, facilitation cascades will have strong indirect effect on ecosystem function due their enhancement of biodiversity. Facilitation cascades can also have a strong direct effect on a number of ecological functions that arise through creation of physical structure. The most immediately obvious benefit is the provision of additional habitat that provides living spaces for more and different organisms. The structure, which is typically more complex than areas outside a facilitation cascade habitat can function as a refuge from predation refuge or physical stresses. Other important functions include soil accretion, altered infiltration rates, and translocation of resources. Through these functions, other emergent ecological properties arise such as increased non-trophic species interaction across multiple trophic levels.
Challenges
Threats
Facilitation cascades can promote ecosystem stability and resilience through positive species interactions. With increasing stress associated with climate change and other anthropogenic impacts, positive interactions will become increasingly important in maintaining ecosystem stability. However, stresses imposed by a threat may, beyond a certain threshold, have detrimental impacts on foundation species, and thereby lead to breakdown of the facilitation cascade.
Natural disasters
Natural disasters, such as earthquakes, natural fires, avalanches and volcanic activities can break down facilitation cascades by killing the foundation species. For example, a seismic uplift in New Zealand associated with the Kaikōura 2016 earthquake caused immediate mortality of both primary and secondary foundation seaweeds followed by cascading destruction of invertebrate biodiversity. These foundation species had not recovered by 2021, and large-scale natural disasters could potentially have legacies on facilitation cascades over decades to centuries as a function of recovery rates of habitat forming organisms.
Climate change
Mutualistic relationships and positive interactions that form the basis of facilitation cascades can ameliorate the impact of increased physical stresses such as drought, temperature extremes, and inundation time associated with climate change. For example, the mutualistic interaction between mussels and cordgrass can increase drought resilience in marsh ecosystems. While these facilitative interactions within a cascade may provide relief from increasing abiotic stresses, they are also vulnerable to the impacts of climate change themselves. Due to interspecific differences in thermotolerance and shifting abundances and distributions of species involved in a cascade, alteration or breakdown of the facilitation cascade may occur due to loss of any component in the cascade. For example, in the marine environment, high temperatures result in coral bleaching and disease, disrupting the relationship between coral host and its symbiotic algae and having downstream impacts on the biodiversity of the system.
Pollution
The introduction of harmful or toxic substances into the environment is a threat to facilitation cascades. Nutrient pollution may initially appear to benefit facilitation cascades by stimulating growth of habitat forming species, but ultimately negative effects associated with excess biomass, such as physically smothering and biogeochemical stressors including oxygen depletion and sulfide toxicity, can overwhelm the facilitation cascade. For example, excessive amounts of nutrients can stimulate prolific growth of secondary foundation species such as seaweed in otherwise oligotrophic seagrass systems, resulting in altered competitive hierarchies where the seaweed outcompetes the seagrass. In other instances, eutrophication can lead to an outright replacement of habitat dominants, such as when macroalgae replaces corals on reefs, leading to a change or loss in components of a facilitation cascade and there a shift in the broader community.
Disease
Disease prevalence and severity are predicted to increase in response to global changes, though its impacts on facilitation cascades remain relatively understudied. High endemic biodiversity, such as that favored by a facilitation cascade, generally decreases the risk of pathogen transmission. However, disease outbreaks that impact a facilitator can reduce its density or alter its phenotype, thereby reducing habitat complexity which dampens its facilitative effects with negative effects on biodiversity.
Overexploitation
Facilitation cascades promote biodiversity and species abundance through positive interactions, which could counteract the consequences of overexploitation. However, harvest of primary or secondary facilitators themselves within the cascade can lead to downstream reductions in species richness, thereby weakening the overexploited species' facilitative effects. For example, harvest of trees can reduce the abundance and diversity of epiphytes that provide shelter and other resources of beneficiary insect communities.
Invasive species
The successful establishment of a nonnative species into a new habitat may be expedited by the habitat provisioning and physical stress amelioration of the facilitation cascade that also promotes high native biodiversity. Furthermore, invasive species may be able to better exploit the benefits of facilitation cascades over native species, leading to spillover effects into nearby habitats and further contributing to their invasion success. Invasive species may also be habitat-forming foundation species capable of initiating their own facilitation cascades as in invasive seaweeds incorporated into worm tubes or invasive kelps that co-occur with native mussels.
Applications in conservation and restoration
Positive interactions can play a critical role in the conservation and restoration of natural systems, and a decision framework to guide practitioners in the incorporation of positive interactions to meet project goals and ecosystem services has been developed. This model can be extended to facilitation cascades which can be harnessed to enhance conservation and restoration. For example, the facilitators within a cascade can be identified as focal or indicator species for monitoring and protection in conservation plans given that these species are likely to support elevated biodiversity and species abundance. Furthermore, the species in a facilitation cascade can be candidate species for restoration due to their ability to initiate community assembly and the complex network of species interactions that underlie important ecosystem properties such as resilience. Finally, engineering with facilitating species in a cascade often provides complementary functions that both enhance the performance of one another and lead to beneficial outcomes that might not be possible with any single species. This is apparent, for example, in shoreline stabilization and enhancement projects where oysters are paired with marsh grasses in which oysters reduce wave energy and erosional stress in adjacent cordgrass zone which in turn builds shoreline and accrete elevational gains.
There are several considerations for practitioners as they incorporate facilitation cascades in their conservation and restoration projects. First, facilitation cascades may occur across multiple habitats through long distance interactions, and so the effectiveness of monitoring and outplanting projects may need to incorporate landscape-scale perspectives or risk failure if essential components of the system are left outside the project scope. Second, while many of the best examples of facilitation cascades in applied contexts come from foundation species or ecosystem engineers that are conspicuous habitat dominants, practitioners should keep in mind that facilitators in a cascade can also include smaller and/or mobile organisms, such as Pollinators that have a positive effect on the reproductive success of habitat-forming vegetation, or mutualists such as Symbiodinium in corals and mycorrhizal fungi in terrestrial plants. Third, facilitation cascades commonly incorporate multiple Trophic levels and/or disparate taxonomic and functional groups, and so restoration projects (or investigations for that matter) need to take a community-wide approach to their design. A 'plant restoration project' is unlikely to meet its management goals without considering the plant interactions with pollinators, invertebrates, epiphytes, etc. Fourth, species mimics may be necessary to jump start a facilitation cascade or replace a living component that may not be practically introduced. Such engineering approaches have already been demonstrated in projects such as seawalls. Finally, the overall importance of facilitation cascades is likely to increase with climate change as associated stressors such as elevated temperature and modified precipitation regimes intensify. Facilitation cascades may suddenly be apparent or important where they were previously undetected, and practitioners may become increasingly dependent on such ecological tools as adaptable and resilient components in their projects.
References
Biological interactions
Symbiosis
Systems ecology
Conservation biology
Habitat
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72,276,375 | https://en.wikipedia.org/wiki/Albert%20Rakoto%20Ratsimamanga | Albert Rakoto Ratsimamanga (28 December 1907 – 16 September 2001) was a Malagasy physician, biochemist and diplomat. Born into a disgraced royal family; Ratsimamanga trained as a doctor of exotic medicine in French Madagascar and France, where he pioneered modern nutraceuticals. Ratsimamanga returned to Madagascar and, with his wife, Suzanne Urverg-Ratsimamanga, in 1957, established the which specialised in herbal medicine.
While in France, Ratsimamanga was involved in Madagascar's independence efforts, and after independence, he became the Malagasy Republic's first ambassador to France and helped shape its foreign affairs. Ratsimamanga is considered one of Madagascar's most renowned scholars and bestowed upon him the highest orders of merits nationally and internationally. He was also one of the founders of The World Academy of Sciences (1983) and the African Academy of Sciences (1985), and was selected Madagascar's Man of the Century.
Early life and education
Albert Rakoto Ratsimamanga was born on 28 December 1907, in Antananarivo, Madagascar, to Razanadrakoto Ratsimamanga and Lala Ralisoa. He was the grandson of Prince Ratsimamanga, uncle and advisor to Queen Ranavalona III, who was executed in 1897 at the beginning of the French colonisation of Madagascar. When Albert was only eleven years old, his father died in 1918 from heavy drinking.
He received his early education at the Faculty of Medicine, University of Antananarivo, until he became a doctor of Indigenous Medicine in 1924. Ratsimamanga was a member of the Malagasy delegation to the 1930 Colonial Exhibition in Paris, during which he decided to join the University of Paris to become a Doctor of Science (MS) and a Doctor of Medicine (MD). He also graduated from the Institute of Exotic Medicine and the Pasteur Institut, and founded the association of Malagasy Students in France.
Career
Research
Ratsimamanga started working at the French National Centre for Scientific Research (CNRS) in 1945 after he was approached by Frédéric Joliot-Curie, CNRS's research director and Nobel prize laureate in Chemistry (1935). At CNRS, he pioneered the study of Human blood group systems, and treatments for leprosy and tuberculosis. Ratsimamanga work showed the presence of hormones in the diet and their role in the development of the body, while eliminating the factors of cellular detoxification, especially in the liver.
Ratsimamanga was the founding director of the (IMRA) in 1957. IMRA was focused on Phytotherapy to use local plants and traditional practices to cure diseases, i.e., traditional pharmacopoeia. IMRA succeeded in using the Syzygium cumini tree as an anti-diabetic agent, and creating alternative medicines against malaria, leprosy, asthma, lithiasis, blood pressure, hepatitis and other common conditions.
Ratsimamanga was the head of Malagasy National Academy, and a Professor Emeritus of the Faculty of Medicine, University of Antananarivo. He was one of the founders of the World Academy of Sciences in 1983, and the African Academy of Sciences in 1985. He was a member of the Royal Academy for Overseas Sciences, Institut de France (1966), and the Académie Nationale de Médecine (1967).
Politics
Ratsimamanga was a pacifist and politically active, and during his years of study, he forged close relationships with French intellectual and political circles. While in France, he co-founded the association of Malagasy Students in France and the Democratic Movement for Malagasy Renovation (MDRM) in 1946 with Jacques Rabemananjara, Joseph Raseta and Joseph Ravoahangy Andrianavalona. MDRM led the protests against the bloody repression of the Malagasy Uprising of 1947. However, MDRM was known to be dominated by Hova elites, who had been politically prominent in the former Merina royal court and wanted to regain the political dominance of the Merina upon independence. Jacques Rabemananjara, Joseph Raseta and Joseph Ravoahangy Andrianavalona were later sentenced to life in prison but were granted amnesty in 1958. Ratsimamanga claimed that he was unaware of the uprising and, thus, was not involved. Later in 1949, Ratsimamanga created the Malagasy National Council, a Government in exile. It was a failure.
On 26 August 1948, Ratsimamanga represented Madagascar at the World Congress of Intellectuals in Defence of Peace, which took place between the 25 to 28 August 1948 of August at Wrocław University of Science and Technology, Poland, and played a role in the framing of the communist powers as supporters of peace, and on the opposite side, portraying the West as a threat to peace.
Ratsimamanga was a member of the delegation that negotiated Madagascar's independence from France. 77% of Malagasy voted for independence in the 1958 referendum, and after the independence, Ratsimamanga was appointed the Malagasy Republic ambassador to France from 1960 to 1972. After the 1972 Coup d'état, on 14 December 1972, he was appointed the first Ambassador of the Malagasy Republic to China and the Soviet Union. He later established embassies in West Germany, North Korea, and Sierra Leone.
Furthermore, Ratsimamanga represents the Malagasy Republic at the European Economic Community, UNESCO, and Food and Agriculture Organization. He also became UNESCO Vice-chairman of the Executive Council.
Personal life and death
Ratsimamanga married Suzanne Urverg-Ratsimamanga on 23 March 1963. She was a French Ashkenazi Jewish biochemist, a Fellow of the World Academy of Sciences (1989), and the African Academy of Sciences (1987), and IMRA's Chair and Albert's closest collaborator. With Albert, she co-founded "Albert and Suzanne Rakoto Ratsimamanga Foundation" within IMRA.
Ratsimamanga died on 16 September 2001, aged 93, in Antananarivo, Madagascar. A state funeral was held for him.
Awards and honours
Ratsimamanga was awarded the Grand Cross of the Malagasy National Order, First Class Grand Cross of the Order of Merit of the Federal Republic of Germany, Grand Officer of the Legion of Honor of France, Grand Officer of the National Order of Scientific Merit of France, National Order of the Lion of Senegal, Commander of the Ordre des Palmes académiques, Commander of the Order of Merit of Congo - Brazzaville, Commander of the Ordre national du Mérite of France, and Grand Prize from the Royal Academy for Overseas Sciences. He was selected Madagascar's Man of the Century in 1999.
Ratsimamanga was a Founder Fellow of the World Academy of Sciences (FTWAS) in 1983, and the African Academy of Sciences in 1985 (FAAS). He was awarded an Honorary Doctorate from the Cheikh Anta Diop University in 1973.
Legacy
Albert Rakoto Ratsimamanga is considered one of Madagascar's most renowned scholars. A commemorative stamp was issued in his memory in 2002, and the Institut de France minted a coin tribute to Ratsimamanga. Ratsimamanga's legacy can be seen as a
References
Further reading
Suzy Andrée Ramamonjisoa (2007). Albert Rakoto Ratsimamanga et moi. Bibliothèque malgache (in French). .
Albert Rakoto Ratsimamanga and Patrick Rajoelina (2001). Madagascar: l'énigme de 1947: mémoires. Paris: L'Harmattan (in French). . .
Didier Galibert (2012). Cosmopolitisme impérial et nationalisme: La vie circulaire d'Albert Rakoto Ratsimamanga (1907–2001). French Colonial History. 13: 175–187. .
Raymond William Rabemananjara (1998). Un fils de la lumière: Biographie d'Albert Rakoto Ratsimamanga (in Italian). 1–190
1907 births
2001 deaths
TWAS fellows
Founder fellows of the African Academy of Sciences
Malagasy scientists
Malagasy politicians
Biochemists
20th-century physicians
Academic staff of the University of Antananarivo
University of Antananarivo alumni
University of Paris alumni
Ambassadors of Madagascar to France
Ambassadors of Madagascar to China
Ambassadors of Madagascar to the Soviet Union
Ambassadors of Madagascar to West Germany
Ambassadors of Madagascar to North Korea
Ambassadors of Madagascar to Sierra Leone
Ambassadors of Madagascar to the European Economic Community
Permanent delegates of Madagascar to UNESCO
Representatives of Madagascar to the Food and Agriculture Organization
Recipients of orders, decorations, and medals of Madagascar
Recipients of the Order of Merit of the Federal Republic of Germany
Recipients of the Legion of Honour
Recipients of orders, decorations, and medals of Senegal
Recipients of the Ordre des Palmes Académiques
Recipients of the Ordre national du Mérite
20th-century biochemists | Albert Rakoto Ratsimamanga | [
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72,276,491 | https://en.wikipedia.org/wiki/Barnlund%27s%20model%20of%20communication | Barnlund's model is an influential transactional model of communication. It was first published by Dean Barnlund in 1970. It is formulated as an attempt to overcome the limitations of earlier models of communication. In this regard, it rejects the idea that communication consists in the transmission of ideas from a sender to a receiver. Instead, it identifies communication with the production of meaning in response to internal and external cues. Barnlund holds that the world and its objects are meaningless in themselves: their meaning depends on people who create meaning and assign it to them. The aim of this process is to reduce uncertainty and arrive at a shared understanding. Meaning is in constant flux since the interpretation habits of people keep changing. Barnlund's model is based on a set of fundamental assumptions holding that communication is dynamic, continuous, circular, irreversible, complex, and unrepeatable.
Cues are of central importance in Barnlund's model. A cue is anything to which one may attribute meaning or which can trigger a response. Barnlund distinguishes between public, private, and behavioral cues. Public cues are available to anyone present in the communicative situation, like a piece of furniture or the smell of antiseptic in a room. Private cues are only accessible to one person, like sounds heard through earphones or a pain in one's chest. Behavioral cues are under the direct control of the communicators, in contrast to public and private cues. They include verbal behavioral cues, like making a remark about the weather, and non-verbal behavioral cues, such as pointing toward an object. Barnlund's model uses arrows going from the communicators to the different types of cues. They represent how each person only gives attention to certain cues by decoding them while they encode and produce behavioral cues in response. Barnlund developed both an intrapersonal and an interpersonal model. The intrapersonal model shows the simpler case where only one person is involved in these processes of decoding and encoding. For the interpersonal model, two people participate. They react not just to public and private cues but also to the behavioral cues the other person produces.
Barnlund's model has been influential as the first major transactional model of communication. This pertains both to its criticism of earlier models and to how it impacted the development of later models. It has been criticized based on the claim that it is not effective for all forms of communication and that it fails to explain how meaning is created.
Background
Dean Barnlund found that previous communication models were missing key components that are part of the communication process and believed communication to be a continuous and simultaneous process challenging long held beliefs of the Linear Model of Communication. This belief led to the creation of his most well known contribution to the field of communication: the Transactional Model of Communication.
Barnlund understands models as attempts to create a simplified picture of an underlying complex reality. This is especially relevant for such a complex process as communication. A good model manages to portray the most salient features at a single glance and may thus assist researchers in their empirical studies. However, this form of simplification also comes with risks like overlooking or distorting factors present in real life. Barnlund's model aims to present the main components of communication in terms of the functions they have.
Barnlund formulated his transactional model of communication as a response to the simplifications and limitations found in various earlier models that take the form of linear transmission models and interaction models. Linear transmission models, like the Shannon–Weaver model, see communication as a linear process: a sender encodes their idea in the form of a message and transmits this message through a channel to a receiver. The receiver has to decode the message in order to understand it. However, as many subsequent communication theorists have pointed out, linear transmission models are too simple to account for all forms of communication. In regular face-to-face conversation, for example, there is usually no designated sender and receiver. Instead, both participants send and receive messages. This problem is partially resolved by interaction models, like Schramm's model. For interaction models, communication is a two-way process. They include a feedback loop through which messages are exchanged back and forth. They are not linear but circular and both participants take turns in encoding and decoding messages. Both linear transmission models and interaction models have in common that they understand communication as the transmission or exchange of meaning.
Barnlund tries to overcome the limitations of these approaches by emphasizing the complexity of communication. He agrees with interaction models that all participants act both as sender and receiver. But he goes beyond them by pointing out that encoding and decoding are not two distinct processes but two simultaneous and interdependent aspects of the same process. He rejects the idea that meaning exists prior to communication. He sees it instead as a product of communication that the communicators assign to the world around them. In his words, communication "is the production of meaning, rather than the production of messages".
Nature of communication
Communication and meaning
For Barnlund, the world and its contents by themselves are meaningless. They only become intelligible and significant because meaning is assigned to them. This ordering process does not happen automatically but is a product of the mind and has to be learned. Barnlund uses the term "communication" in a very wide sense referring to "those acts in which meaning develops within human beings". This involves typical forms of verbal communication, like talking to a friend about an event that just occurred. It also includes non-verbal communication such as pointing somewhere or grimacing in pain. However, since the processes of meaning-making are not restricted to exchanges with other people, there are also forms of communication taking place when a person is all by themselves. The reason is that they decode internal and external stimuli and encode the corresponding behavioral responses. Since these processes do not stop during sensory deprivation and sleep, Barnlund includes even these cases as forms of communication.
For Barnlund, the aim of communication is to reduce uncertainty, to act efficiently, and to arrive at some form of shared understanding of a phenomenon by negotiating its meaning. He emphasizes the active nature of this process: "meaning is something 'invented', 'assigned', 'given', rather than something 'received'." It follows that meaning is not an intrinsic property of sounds and gestures but is ascribed to them. For example, some cultures assign to nodding the meaning of "yes" but it means "no" in other cultures. In this case, the meaning of the nod arises only as it is interpreted. This applies equally to national flags or traffic signs, which do not contain meaning by themselves. Instead, anything gets its meaning because it is interpreted in certain ways. In this regard, Barnlund understands communication as the production of meaning and not as the mere production or exchange of messages. Meaning is in constant flux because the practice of interpretation is continuously evolving, both on the individual and the societal level. So what meanings are assigned to the same thing may change a lot as time passes. For example, by learning a new word, a person starts to ascribe a new meaning to the corresponding sound. On the societal level, many new phrases were introduced with the rise of online communication and the meaning of some preexisting phrases also changed as a result. For this reason, the different interpretations are never fully consistent with each other.
Fundamental assumptions
Barnlund's model is based on a set of fundamental assumptions: communication is dynamic, continuous, circular, irreversible, complex, and unrepeatable. Communication is dynamic in the sense that it is not a static entity but an everchanging process. It is continuous because the process of assigning meanings to objects in the world happens all the time. This process has no clear beginning or end and goes on even under sensory deprivation. By seeing communication as circular, Barnlund rejects the idea found in linear transmission models that messages pass in a linear process from a sender to a receiver. Instead, all participants act both as sender and receiver. In the widest sense, this even happens when there is only one person present who is making sense of the world around them.
Communication is irreversible in the sense that the effects it has on the communicators cannot be undone. In this regard, communication influences and changes the participants in various ways. So after a conversation, there is usually no way to go back and restore the state of the communicators prior to it. Communication is complex for many reasons: it has many components, there are many types of communication, and many factors determine how the communicative process unfolds. For this reason, it is also unrepeatable. This means that there is no easy way to have the same communicative exchange again since this would mean controlling all the factors affecting how it plays out. It is often possible to have the same message on two occasions, as when retelling a joke or a news report. But this will usually not have exactly the same effects. This implies that the same person may interpret the same message at two distinct occurrences very differently depending on the situation, context, and personal changes in between.
Model and main components
Barnlund's model of communication is one of the most well-known transactional models of communication. It was published by Dean Barnlund in his 1970 article A Transactional Model of Communication. It is based on the idea that there are countless external and internal cues present. Communication consists in decoding them by ascribing meaning to them and encoding appropriate responses to them. This happens both for intrapersonal communication, when no other person is present, and for interpersonal communication, when communicating with others.
Cues
Cues are any objects, signs, or aspects to which one "may attribute meaning" or which "may trigger interpretations or reactions of one kind or another". Barnlund understands communication as a response to cues. There is always a vast number of cues present at any moment but people interpret and react only to some of them. There are many ways in which communicators may respond to cues and what influence they have. Explicitly talking about a cue is only one way to respond and many cues influence the process in other ways.
Barnlund distinguishes three types of cues: public cues, private cues, and behavioral cues. Public cues belong to the environment and are not under the direct control of the communicators. Some of them are natural cues, which were not created by human intervention. Examples of natural cues are atmospheric conditions, the visual properties of minerals, or the shape of vegetables. They contrast with artificial cues resulting from human manipulation of the environment, such as processed wood, a pile of magazines, or the smell of antiseptic in a doctor's waiting room. Public cues are accessible to anyone in the environment. Private cues, by contrast, are only accessible to the specific individual. They include listening to a podcast through earbuds and the coins hidden in one's pocket. Many private cues are internal, such as thoughts, emotions, or feeling sudden pain in one's chest.
The communicators' behavior is also a source of cues, such as non-verbal cues in the form of gestures or verbal cues when talking or writing. Public and private cues are outside the direct control of the communicators, in contrast to behavioral cues, which are controlled by the communicators and constitute reactions to other cues. Behavioral cues include both deliberative acts, such as picking up a magazine, and unconscious mannerisms, such as moving the eyebrows in response to an unexpected event.
The central aspect of verbal communication concerns the encoding and decoding of verbal behavioral cues. However, they are not the only cues relevant and their interpretation usually depends on the other cues present. For example, a different meaning may be assigned to a remark depending on whether it was made at a clinic or a golf course (public cue) and whether the speaker enunciates it with a stern face or flushes at the same time (non-verbal behavioral cue). This way, the communicators interpret all kinds of cues to reduce the ambiguity of the situation.
An important aspect of the different types of cues is that they can be transferred from one type into another type. For example, a private cue in the form of thought is transferred into a verbal behavioral cue when it is expressed in speech. And public cues may be changed into private cues, for example, when a book is closed to hide its contents from other communicators.
Because of the vast number of cues available at any moment, communicators have to select which ones they want to attend to. Different communicators focus on different cues in their decoding: some give special weight to non-verbal cues and some focus more on private cues. This selection also depends on the valence of the cue, i.e. the positive or negative meaning the communicator ascribes to it. For Barnlund, the aim of communication is to reduce uncertainty. For it to be successful, as many relevant cues as possible have to be interpreted. In this process, the communicators should try to keep an open mind about the different potential meanings of each cue. The goal is to arrive at a coherent picture of the meaning of all or most of the interpreted cues since the interaction of all of them shapes understanding.
Intrapersonal model
Intrapersonal communication is a special form of communication since it does not involve a second person. In certain respects, it is similar to other forms of communication: the person decodes internal and external stimuli in trying to make sense of themselves and the world around them and then encodes neuro-muscular reactions in response.
Barnlund first discusses the case of intrapersonal communication since fewer elements are involved. For this reason, it is easier to understand than interpersonal communication. In his diagram, the circle in the middle represents the person and the areas around it symbolize the different types of cues currently present. The person is engaged in the activity of decoding cues (orange arrows) and encoding responses to these cues (yellow arrow). The orange arrows point toward the cues to express that meaning is actively assigned to them and not just received or read off. The spiral inside the person indicates that the activities of encoding and decoding are not distinct processes but different and interdependent aspects of one and the same process.
Barnlund uses the example of a person waiting alone in the reception room of a clinic. This person is confronted with various cues and assigns meaning to them. Some of them are public cues, like the furniture, the magazines on the table, and the rainstorm outside the window. Others are private, like the person's memory of their last visit here or the mint taste from their chewing gum. But they also include behavioral cues in the form of the person's awareness of their bodily movements, as when flipping a page of the magazine or altering their position in the chair. It may change from one moment to the next which cues are present, which ones the person attends to, and how the person responds to them.
Interpersonal model
Interpersonal communication is the paradigmatic form of communication. It happens when two or more people interact with each other. It can take the form of a regular face-to-face conversation but includes many other forms, such as phone calls, texting, or slipping someone a note. For Barnlund, interpersonal communication is significantly more complex because more people and more cues are involved. There is no clear division between sender and receiver since the communicators play both roles at the same time. As shown in the diagram, there are two sets of private cues, one for each communicator, just like there are two sets of non-verbal behavioral cues. In addition, there are now also verbal behavioral cues present. They correspond to the linguistic exchange taking place, such as what the speaker says or what the teacher writes on a blackboard. The yellow arrows show how each participant generates both verbal and non-verbal behavioral cues. The orange arrows represent the activity of decoding cues. For interpersonal communication, each communicator is also aware of the verbal and non-verbal behavioral cues generated by the other party. But how they react to these cues depends on all the other cues as well.
Barnlund uses the example of a doctor entering the waiting room to greet their patient. The different public cues discussed before, such as the furniture and the magazines, are still present. But they may be slightly different from person to person. For example, a watch hanging on the wall behind the patient is only visible to the doctor but not to the patient. The doctor's well-hidden fatigue is a private cue to them of which the patient is not aware. When the doctor greets the patient and extends their hand, they produce both verbal and non-verbal behavioral cues, of which the patient becomes aware and has to decide how to respond to them. Their response will again generate verbal and non-verbal behavioral cues. Many of the other cues influence how this exchange unfolds. For example, a private cue in the form of a fond memory the patient has of the doctor may have a positive impact. But a public cue in the form of an unpleasant smell in the waiting area may have a negative impact, even if this smell is never mentioned in their exchange.
Barnlund points out that, for interpersonal communication, the participants usually pay more attention to their own behavior than otherwise. The reason is that they are aware that the other person interprets them and therefore exercise more control of the behavioral cues they produce. This form of self-regulation happens as soon as the other person is present, often before any verbal communication has taken place.
Influence and criticism
Barnlund's objections to earlier models of communication have been influenced various subsequent theorists. Barnlund’s scholarship introduced theorists to new perspectives on the diverse ways communication occurs. This pertains specifically to his focus on the complexity of communication. This complexity is often missed in the attempt to simplify the process in the form of a compact model. Another influential element is his idea that meaning is constructed by the communicators and attributed to cues rather than merely received and sent around in the form of messages. Barnlund's emphasis on the role of interpretation, personal meaning ascriptions, and their constant flux has been adopted by many subsequent theorists. His transactional model is often seen as the origin of constitutive models of communication. It has been applied to fields such as teaching, market research, and business communication.
Barnlund's model has been criticized in various ways. For example, it has been argued that it is effective for face-to-face and small-group communication but not for reading and writing or for mass communication since the role of the specific environment is less pronounced in these cases. Another objection is that Barnlund's model fails to explain how meaning is created. For example, it does not take into account how communicative competence may help the participants take conscious control over how meaning is created and changed. Nevertheless, Barnlund’s communication model were still viewed positively, as some saw his contribution to communication could be applied to different fields of studies such as business, hospitality, healthcare, and education. His new findings helped improve other communication scholarships, such as the study of communication styles in different cultures. His findings also had implications for the study of small group communication in regard to factors involved and how it can improve our communication within them.
References
Bibliography
Communication studies
Communication theory
Conceptual modelling
Human communication | Barnlund's model of communication | [
"Biology"
] | 3,999 | [
"Human communication",
"Behavior",
"Human behavior"
] |
72,276,939 | https://en.wikipedia.org/wiki/Leucocoprinus%20armeniacoflavus | Leucocoprinus armeniacoflavus is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 2012 by Erhard Ludwig who classified it as Leucocoprinus armeniacoflavus and placed it in the Leucocoprinus section Denudati.
Description
Leucocoprinus armeniacoflavus is a small yellow dapperling mushroom with pale yellow flesh.
Cap: 1.5-3.5 cm wide and campanulate (bell shaped) when mature with a pronounced umbo. The surface is yellow and covered in very coarse, yellow or pale yellow scales that do not wipe off whilst the centre of the cap is orange-brown or 'apricot' coloured. Sulcate striations run to the cap margins when mature. Stem: 3–5 cm tall and 35-50mm thick with a gradual taper up from the bulbous (clavate) base. The surface is yellow like the cap but is smooth and devoid of scales. The ascending, membranous stem ring is also yellow and may be permanent. Gills: Free, crowded and creamy coloured with a slight, light pinkish tone.Spores: Ovoid to amygdaliform or subcylindrical without a germ pore. Dextrinoid and metachromatic. 7–10.5 (12) x 4.5-6 μm. Basidia: 2-4 spored.
The mushroom dries to an ochre colour.
Habitat and distribution
The specimens studied by Ludwig were found growing outside on the ground in Potsdam, Brandenburg, Germany where they were growing between a Pachyasandra species and Lamium purpureum (deadnettle). As of the 2012 publication they are known only from this location in Germany however they may have been introduced like many other Leucocoprinus species or may have a larger distribution but are simply not recorded.
GBIF has no recorded observations for this species.
Etymology
The specific epithet armeniacoflavus derives from the Latin armeniacus meaning apricot coloured or yellow with a tinge of orange and flavus meaning yellow. It is named for the apricot yellow colouration of the central disc or umbo.
Similar species
Leucocoprinus aureofloccosus is very similar but has a delicate stem ring which quickly disappears and larger spores.
Leucocoprinus thoenii may be similar with more pronounced striations and larger spores.
Leucocoprinus flavus may be the most closely related known species but lacks a scaly cap and has smaller scales.
References
armeniacoflavus
Fungi described in 2012
Fungus species | Leucocoprinus armeniacoflavus | [
"Biology"
] | 555 | [
"Fungi",
"Fungus species"
] |
72,277,142 | https://en.wikipedia.org/wiki/Greve%20Prize | The Greve Prize of the German National Academy of Sciences Leopoldina honors outstanding research achievements since 2022. The prize is financed by the "Foundation for Science and Culture Helmut and Hannelore Greve". The award is endowed with €250,000 and is awarded every two years in Hamburg.
Recipients
2022 Kerstin Volz (University of Marburg) and (University of Giessen) for basic research on rechargeable high-performance batteries
References
External links
Awards established in 2022
2022 establishments in Germany
German National Academy of Sciences Leopoldina
German science and technology awards
Scientific research awards | Greve Prize | [
"Technology"
] | 125 | [
"Science and technology awards",
"Science award stubs",
"Scientific research awards"
] |
72,282,418 | https://en.wikipedia.org/wiki/Kalam-series%20engines | The Kalam-series engines are a set of five solid-propulsion carbon composite rocket engines being developed by Skyroot Aerospace. The engines are named after India’s former President APJ Abdul Kalam.
They are to be used in conjunction with the Raman Engine during the launches of Vikram-series small-lift launch vehicles.
List of engines
Kalam 5
Kalam 80
Kalam 100, to power the third stage of Vikram 1.
Kalam 250
Kalam 1000
References
Rocket engines of India | Kalam-series engines | [
"Astronomy"
] | 102 | [
"Rocketry stubs",
"Astronomy stubs"
] |
72,282,761 | https://en.wikipedia.org/wiki/Leucoagaricus%20lacrymans | Leucoagaricus lacrymans is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 2004 by the Indian mycologists T.K. Arun Kumar & Patinjareveettil Manimohan who classified it as Leucocoprinus lacrymans.
In 2017 it was reclassified as Leucoagaricus lacrymans by the Chinese mycologists Zai-Wei Ge & Zhu-Liang Yang based on phylogenetic analysis.
Description
Cap: 3–8.3 cm wide, starting cylindrical but truncate on the top and expanding to become campanulate to convex and finally flattening with age whilst often retaining a distinct umbo. The surface is white to creamy coloured and covered with minute, flattened (appressed) cinnamon to rusty brown to purplish brown scales which are sparser at the margins but denser towards the centre of the cap where they become more granular (granulose) or slightly velvety (velutinate). The cap margins have striations (sulcate-striate) and are entire, starting incurved before flattening with age and becoming fissile (prone to splitting slightly). The cap edges are often covered with yellow to reddish brown guttation the same as that seen on the stem. The cap flesh is white or whitish and thin (3mm thick) and discolours to a pale orange when cut or a greyish orange with longer exposure on cut surfaces. Stem: 4–12 cm tall and 5-6mm thick running almost equally along the length or tapering slightly towards the top. The surface is white or a dirty white colour and darkens to brownish with age and is velvety when young (velutinous to villose) but has some flattened fibrils when older (appressed-fibrillose). It is often covered with beads of yellow to reddish brown guttation. The interior is hollow and the base of the stem can display white mycelial cords (rhizomorphs). The membranous stem ring is located towards the top of the stem (superior). Kumar and Manimohan note the ring as being white and usually disappearing without a trace (evanescent) whilst Ge and Yang state that it is brown and persistent. Gills: Free without a collar, moderately crowded and white but aging to a yellowish white and then discolouring reddish with age or upon drying. They are thin (up to 4mm wide) and may bulge in the middle (ventricose). The gills are of two or three different lengths and the edges are finely fringed and may be tinted greyish on older specimens. Smell: Indistinct. Spore print: White. Spores: Ellipsoidal to broadly ellipsoidal when viewed from the side and ellipsoidal, ovoid or subglobose front on. They are hyaline and smooth with a distinct germ pore. Dextrinoid. 5-13 x 4.5-11μm. Basidia: 4 spored.
Habitat and distribution
The specimens studied by Kumar and Manimohan were collected in Kerala State, India and were found growing on soil and decaying leaf litter around the base of coconut trees where they were solitary or growing in clusters. Ge and Yang not that the species grows in tropical forests and is known from India and China.
Etymology
The specific epithet lacrymans derives from Latin and means weeping, in reference to the guttation this species presents with.
Similar species
Leucocoprinus zelanicus is noted as being similar however is distinguished by the smooth stem, the lack of guttation on the cap and stem as well as microscopic differences including a smaller spore size.
References
lacyrmans
Fungi described in 2004
Fungus species | Leucoagaricus lacrymans | [
"Biology"
] | 789 | [
"Fungi",
"Fungus species"
] |
72,283,097 | https://en.wikipedia.org/wiki/Leucocoprinus%20flavipes | Leucocoprinus flavipes is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1888 by the French mycologists Narcisse Théophile Patouillard and Albert Gaillard who classified it as Leucocoprinus flavipes.
In 1891 the species was included in Pier Andrea Saccardo's Sylloge fungorum omnium hucusque cognitorum as Hiatula flavipes resulting in the creation of this as a synonym.
Description
Leucocoprinus flavipes is a small white dapperling mushroom with thin flesh.
Cap: 3-5cm wide and very thin, campanulate and flattening with age with an umbo or central disc. The surface is pure white and has striations running to the centre disc, which is smooth and greenish. Stem: 10-12cm tall and 3-5mm thick and brittle with a 10mm thick bulbous base. The surface is greenish yellow whilst the interior is hollow. The membranous stem ring is white and is movable but may disappear. Gills: Free with a wide collar, crowded and white. The gills are thin and delicate. Spore print: White. Spores: Subglobose with a large apical germ pore. No measurements are provided in the 1888 text and likely would not be accurate by modern standards if they were.
Patouillard and Gaillard describe the mushroom as being very ephemeral and disappearing soon after the sun rises. They compare it to Coprinus though note it is not deliquescent and to Hiatula fragilissima (now known as Leucocoprinus fragillissimus). This species may be a synonym of L. fragillissimus that has not been reclassified or a similar species that has just been mostly forgotten.
Habitat and distribution
The specimens studied by Patouillard and Gaillard were found in humus on the edge of the woods on the left bank of the Orinoco river opposite Puerto-Zamuro in Venezuela.
Similar species
Leucocoprinus fragillissimus
References
flavipes
Fungi described in 1888
Fungus species | Leucocoprinus flavipes | [
"Biology"
] | 453 | [
"Fungi",
"Fungus species"
] |
72,283,201 | https://en.wikipedia.org/wiki/Robert%20M.%20Pringle | Robert Mitchell Pringle (born February 9, 1979) is an American biologist and conservationist.
He is professor and director of undergraduate studies in the department of ecology and evolutionary biology at Princeton University.
Pringle's research combines field and laboratory methods to understand biological interactions and biodiversity loss in terrestrial ecosystems, chiefly African savannas.
One major focus of Pringle's work has been understanding the ecological impacts of armed conflict and the dynamics of postwar ecosystem restoration in Mozambique’s Gorongosa National Park.
Early life and education
Pringle was born in Ann Arbor, Michigan.
His father, cell biologist John Pringle, and mother, cancer biologist Beverly Mitchell, encouraged his love of nature.
Pringle’s sister, Elizabeth, is a professor of ecology and evolutionary biology at the University of Nevada, Reno.
Pringle graduated from the University of Pennsylvania in 2001, completed an M.Sc. degree at the University of Oxford in 2004, and received a Ph.D. in biology from Stanford University in 2009.
He was a Junior Fellow in the Harvard Society of Fellows before joining the Princeton faculty in 2012.
Career
Pringle's early research experimentally documented the keystone roles played by large herbivores, carnivores, and subterranean termites in regulating biodiversity and ecosystem function in savannas.
In 2013, Pringle's lab was among the first to use DNA metabarcoding to understand dietary niche differentiation and its role in sustaining the coexistence of animal species.
Pringle also worked with Princeton colleagues Corina Tarnita and Juan Bonachela to develop new theories about the formation of large, regular vegetation patterns, such as the Namib Desert fairy circles.
Pringle's work in Gorongosa has focused on measuring the ecological and evolutionary impacts of losing large herbivores and carnivores, as well as the dynamics of community reassembly as these species have been restored.
This research was featured in the Emmy Award nominated nature documentary, Nature’s Fear Factor.
Pringle serves on the board of the Guanacaste Dry Forest Conservation Fund, a nonprofit organization supporting conservation and biodiversity research in Costa Rica’s Area de Conservación Guanacaste. With Simon Levin and Corina Tarnita, he is the editor of the Monographs in Population Biology published by Princeton University Press, a series of influential books in ecology and evolutionary biology.
Recognition
Pringle received the Early Career Investigator Award from the American Society of Naturalists in 2011 and was named an Early Career Fellow of the Ecological Society of America in 2015.
Students at Princeton have described Pringle as a passionate and creative teacher.
The parasitoid wasp Lytopylus robpringlei was named after Pringle in 2011, in honor of his conservation work. This species was later transferred into the genus Aerophilus.
In 2024, Pringle was named a Guggenheim Fellow.
Personal life
Pringle is married to Corina Tarnita, a mathematician and biologist who is also a professor at Princeton. Pringle and Tarnita have collaborated on multiple research projects, and they have one daughter.
References
External links
Pringle Laboratory Lab homepage
Profile on the Website of the High Meadows Environmental Institute
Profile on the Website of Princeton’s Department of Ecology and Evolutionary Biology
Niche partitioning and species coexistence Video on YouTube
Think Like a Scientist: Gorongosa Video
Nature’s Fear Factor PBS NOVA documentary
Guggenheim Foundation profile
21st-century American biologists
American ecologists
Ecologists
American evolutionary biologists
Conservation biologists
Princeton University faculty
Harvard Fellows
Stanford University alumni
Alumni of the University of Oxford
University of Pennsylvania alumni
1979 births
Living people | Robert M. Pringle | [
"Environmental_science"
] | 753 | [
"Ecologists",
"Environmental scientists"
] |
72,283,324 | https://en.wikipedia.org/wiki/NGC%201570 | NGC 1570, mistakenly called NGC 1571, is a faint galaxy located in the southern constellation Caelum, the chisel. It has a blue magnitude of 13.2, making it visible through a medium sized telescope. Based on a redshift of z = 0.014760, the object is estimated to be 198 million light years (60.9 megaparsecs) away from the Local Group. It appears to be receding with a heliocentric radial velocity of .
NGC 1570 has a galaxy morphological classification of S0, indicating that it is a lenticular galaxy. It has also been catalogued as a peculiar elliptical galaxy. The central black hole has a mass 297 times that of the Sun. It is estimated to be 8.9 billion years old, younger than the Milky Way. The average iron abundance of the galaxy is 135% that of the Sun's. NGC 1570 is said to be round in shape, making it more likely to be an elliptical galaxy.
The galaxy was first discovered by Sir John Herschel in November 1835. A month later, he observed NGC 1570 again and mistakenly called it NGC 1571 due to imprecise coordinates. NGC 1570 is part of a small galaxy group called LDC 302. It is the brightest member.
References
Lenticular galaxies
Elliptical galaxies
Caelum
1570
014971
14971 | NGC 1570 | [
"Astronomy"
] | 277 | [
"Caelum",
"Constellations"
] |
72,283,961 | https://en.wikipedia.org/wiki/Privileged%20access%20management | Privileged Access Management (PAM) is a type of identity management and branch of cybersecurity that focuses on the control, monitoring, and protection of privileged accounts within an organization. Accounts with privileged status grant users enhanced permissions, making them prime targets for attackers due to their extensive access to vital systems and sensitive data.
Implementation and models
PAM can be implemented as a Software-as-a-Service (SaaS) solution or an on-premises offering, providing organizations with the flexibility to choose the model that best fits their needs. The objective is to safeguard, regulate, observe, examine, and manage privileged access across diverse environments and platforms. PAM solutions adopt Zero Trust and least-privilege frameworks, guaranteeing that users receive only the essential computer access control needed for their roles, thereby minimizing the likelihood of unauthorized entry or security incidents.
PAM focuses on securing and overseeing privileged accounts to prevent unauthorized access to critical resources, while SNMP is used for monitoring and managing network devices. These two components can work together to enhance overall network security by ensuring that SNMP configurations and access controls are protected and only accessible to authorized personnel, thus safeguarding against potential security breaches and unauthorized modifications to network settings.
In July 2023, the Keeper Security survey revealed that only 43% of SMBs have deployed Privileged Access Management (PAM) solutions, significantly lower than other leading security technologies such as network, email, endpoint security, and SIEM tools, which all exceed 75% deployment.
Key features
PAM solutions play a crucial role in reducing security vulnerabilities, adhering to information security standards, and protecting an organization's IT infrastructure. They establish a comprehensive system for handling privileged accounts, encompassing the gathering, safeguarding, administration, verification, documentation, and examination of privileged access:
Privileged Session Management controls and records high-risk user sessions, aiding in audit and compliance with searchable session recordings.
Privileged Password Vault secures credential granting with role-based management and automated workflows.
Privileged Threat Analytics check privileged session recordings to identify high-risk users and monitor for questionable behavior and anomalies. This helps in early detection of internal and external threats, allowing for immediate action to prevent breaches.
Least Privileged Access: PAM safeguards the organization and thwarts security breaches by granting administrators precisely the access they need. This method employs a least-privilege security strategy, meticulously allocating administrative permissions across different systems.
UNIX Identity Consolidation replaces native UNIX systems' individual authentication and authorization with a more secure, integrated identity management via Active Directory (AD). This approach broadens AD's authentication and authorization scope to include UNIX, Linux, and Mac systems.
When combined with customer identity access management, Privileged Access Governance enhances governance features. This integration offers cohesive policies, automated and role-specific attestation, and provisioning. It guarantees a consistent governance framework for every employee, irrespective of their position or access level.
Unified access management is an essential component of Privileged Access Management (PAM), encompassing user permissions, privileged access control, and identity management within a Unified Identity Security Platform. It efficiently addresses identity sprawl, streamlining cybersecurity efforts while promoting governance and operational efficiency. By integrating user data across various platforms, it centralizes management and enhances situational awareness, making it a pivotal tool in modern cybersecurity and identity management.
According to Security-First Compliance for Small Businesses book the best practices for managing privileged access (PAM) encompass:
Distinguishing between privileged and non-privileged access for users with elevated permissions.
Constraining the count of users possessing privileged rights.
Restricting privileged rights solely to in-house staff.
Mandating Multi-Factor Authentication (MFA) for accessing privileged accounts.
See also
List of ISO standards 28000–29999
Cybersecurity information technology list
References
Identity management
Computer security procedures | Privileged access management | [
"Engineering"
] | 789 | [
"Cybersecurity engineering",
"Computer security procedures"
] |
72,284,070 | https://en.wikipedia.org/wiki/Elton%20Leme | Elton Martinez Carvalho Leme (born 1960) is a Brazilian who is employed as a judge. He is also a self-taught botanist with a special interest in bromeliads. , the International Plant Names Index listed 629 scientific names which include Leme as a publishing author, including 13 generic names.
Some publications
Journal articles
Books
English translation:
References
1960 births
Living people
20th-century Brazilian botanists
21st-century Brazilian botanists
Taxon authorities | Elton Leme | [
"Biology"
] | 93 | [
"Taxon authorities",
"Taxonomy (biology)"
] |
72,284,579 | https://en.wikipedia.org/wiki/28%20Leonis%20Minoris | 28 Leonis Minoris (28 LMi) is a solitary, orange hued star located in the northern constellation Leo Minor, the lesser lion. It has an apparent magnitude of 5.5, allowing it to be faintly visible to the naked eye. Based on parallax measurements from the Gaia satellite, it is estimated to be 480 light years distant. 28 LMi is approaching the Solar System with a heliocentric radial velocity of . At its current distance, the star brightness is diminished by 0.14 magnitudes due to interstellar dust.
This is a population II giant star with a stellar classification of K1 III. It has a comparable mass to the Sun but has expanded to 22.6 times its girth. It radiates 207 times the luminosity of the Sun from its photosphere at an effective temperature of . It has an iron abundance 90% of the Sun's, making it slightly metal deficient.
References
K-type giants
Population II stars
Leo Minor
BD+34 02123
090040
050935
4081
Leonis Minoris, 28 | 28 Leonis Minoris | [
"Astronomy"
] | 226 | [
"Leo Minor",
"Constellations"
] |
72,284,706 | https://en.wikipedia.org/wiki/Megaherbivore | Megaherbivores (Greek μέγας megas "large" and Latin herbivora "herbivore") are large herbivores that can exceed in weight. The earliest herbivores to reach such sizes like the parieasaurs appeared in the Permian period. During most of the Mesozoic, the megaherbivore niche was largely dominated by dinosaurs up until their extinction during the Cretaceous–Paleogene extinction event. After this period, small mammalian species evolved into large herbivores in the Paleogene. As part of the Late Pleistocene megafauna extinctions, 80% of megaherbivore species became extinct, with megaherbivores becoming entirely extinct in Europe, Australia and the Americas. Recent megaherbivores include elephants, rhinos, hippos, and giraffes. There are nine extant species of terrestrial megaherbivores living in Africa and Asia. The African bush elephant is the largest extant species.
Extant megaherbivores are keystone species in their environment. They defoliate the landscape and spread a greater number of seeds than other frugivores. Extant megaherbivores, like most large mammals, are K-selected species and are characterized by their large size, relative immunity to predation, their effect on plant species, and their dietary tolerance.
Definition
Megaherbivores are large herbivores that weigh more than 1 ton when fully grown. They include both marine and terrestrial herbivores, and are classified as the largest type of terrestrial megafauna (>45 kg).
Evolution
Permian
Megaherbivores first evolved in the early Permian (300 mya). The earliest megaherbivores were synapsids; they became somewhat rare after the Permian–Triassic extinction event. Taxa mainly consisted of dicynodonts, and pareiasaurs. The exact cause of the extinction remains unknown. It is thought that the main cause of extinction was the flood basalt volcanic eruptions that created the Siberian Traps, which released sulfur dioxide and carbon dioxide, resulting in euxinia, elevating global temperatures,
and acidifying the oceans.
Triassic
Lisowicia was the last dicynodont that lived and became extinct in the Late Triassic. Some scientists have proposed that there was never a Triassic–Jurassic extinction event, but others argue that the extinctions occurred earlier. Nevertheless, flood basalts are thought to be the primary driver of the extinctions towards the end of the Triassic.
Jurassic
The taxonomic structure then switched to sauropodomorphs. Other taxa included stegosaurs and ankylosaurs. The change in taxonomy approximately occurred at the same time with the divergence of predominant vegetation and with extinctions. New taxa may have caused competitive exclusion (i.e. predominating and removing another taxa), or they may have adopted the ecological niche of extinct groups.
Cretaceous
From the Triassic to the Cretaceous, a diverse assemblage of megaherbivorous dinosaurs, such as sauropods, occupied different ecological niches. Based on their dentition, ankylosaurs may have mainly consumed succulent plants, as opposed to nodosaurs, which were mainly browsers. It is thought that ceratopsids fed on rugged vegetation, due to their jaw being designed for a crushing effect. Studies on hadrosaur dentition concluded that they primarily fed on fruits.
Paleogene
Following the Cretaceous–Paleogene mass extinction, megaherbivore dinosaurs were extirpated from the face of the earth. One mechanism is thought to have played a major role: an extraterrestrial impact event in the Yucatán Peninsula. For about 25 million years, the earth was void of large terrestrial herbivores that weighed more than 1 ton. After this period, small mammalian species evolved into large herbivores across every continent around 40 mya. The largest of these animals were Paraceratheriidae and Proboscidea. Other taxa included Brontotheriidae. The Sirenia, aquatic megaherbivores, such as Dugongidae, Protosirenidae, and Prorastomidae were present in the Eocene. Megaherbivores inhabited every major landmass in the Cenozoic and Pleistocene before the arrival of humans.
Pleistocene
There were around 50 different species by the Late Pleistocene:
Diprotodon, the largest marsupial to ever exist, was present across the entire Australian continent by the Late Pleistocene. Elsewhere, megaherbivores like glyptodonts were grazing herbivores, that possessed no incisor or canine teeth, but had cheek teeth that would have been able to grind up tough vegetation. They inhabited habitats of South and North America. Ground sloths were herbivores, with some being browsers, others grazers, and some intermediate between the two as mixed feeders. Fossilized specimens were primarily found in South and North America, with one specimen being found as far north as Alaska. Mammoths, like modern day elephants, had hypsodont molars. These features allowed mammoths to live an expansive life because of the availability of grasses and trees. Today, nine of the 50 species persist. The Americas saw the worst decline in megaherbivores, with all 27 species going extinct.
The Quaternary Extinction Event is an event where many species of megafauna (particularly mammals) went extinct. This event caused the disappearances of megaherbivores on most continents on Earth. Climate change and the arrival of humans are considered likely causes of the extinctions. It is thought that humans hunted megaherbivores to extinction, which then led to the extinction of the carnivores and scavengers which had preyed upon those animals. Scientists have proposed that increasingly extreme weather—hotter summers and colder winters—referred to as "continentality", or related changes in rainfall caused the extinctions.
Recent
There are nine extant species of megaherbivores, found in Africa and Asia. They include elephants, rhinos, hippos and giraffes. Elephants belong to the order Proboscidea; an order that has been around since the late Paleocene. Hippopotamuses are the closest living relatives to cetaceans; soon after the common ancestor of whales and hippos diverged from even-toed ungulates, the lineages of cetaceans and hippopotamuses split apart. Giraffidae are a sister taxon to Antilocapridae, with an estimated split of more than 20 million years ago, according to a 2019 genome study. Rhinoceroses may originate from Hyrachyus, an animal whose remains date back to the late Eocene.
Megaherbivores and other large herbivores are becoming less common throughout their natural distribution, which is having an impact on animal species within the ecosystem. This is mainly attributed to the destruction of their natural environment, agriculture, overhunting, and human invasion of their habitats. As a consequence of their slow reproductive rate and the preference for targeting larger species, overexploitation poses the greatest threat to megaherbivores. As time progresses, it is thought that the situation will only worsen.
Ecology of recent megaherbivory
Browsers and grazers
Living species exhibit the following adaptations: they have dietary tolerance, a strong effect on vegetation and with the exception of calves, face little threat from predators.
Elephants and Indian rhinoceroses exhibit both grazing and browsing feeding habits. The hippopotamus and white rhinoceros prefer grazing herbivory, while giraffes and the three other rhinoceros species most often select browsing herbivory. Mammalian megaherbivores predominantly consume graminoids. They prefer eating the leaves and stem of the plant, as well as its fruits. They also exhibit both foregut and hindgut fermentation, with rhinos, hippos, and elephants displaying the former and giraffes displaying the latter. Their metabolic rate is lethargic, and as a result, digestion is slowed. During this prolonged digestion period, high-fiber plant matter is disintegrated.
Due to their size, megaherbivores can defoliate the landscape; because of this, they are considered keystone species in their environment. Megaherbivores affect the composition of plant species, which alters the movement and exchange of inorganic and organic matter back into the production of matter. They can open up areas through feeding behavior, which over time clears vegetation, including invasive alien plants. The number of seeds that megaherbivores spread is greater than that of other frugivores. In addition, megaherbivore grazers, like the white rhino, have a profound impact on short grass. In one study, short grass became more infrequent after the elimination of white rhinos, which effected smaller grazers in the area.
In a 2018 study, it was concluded that megaherbivores were not affected by the "landscape of fear," a landscape in which prey avoid certain hot-spot predation areas, thereby altering predator-frightened trophic cascades. Their feces were most apparent in closed, dense areas, indicating that they distribute resources to risky areas in this "landscape of fear".
Interspecific interactions
Most megaherbivore species are too big and powerful for most predators to kill. Calves are, however, targeted by several predator species. Giraffes are the most preyed upon megaherbivore, as it is not rare for lions to hunt adult giraffes in some places. The young are especially vulnerable, with a quarter to half of giraffe calves not reaching adulthood. In Chobe National Park, lions have been recorded hunting young and sub-adult elephants. Tigers are another known predator of young elephants. Hippo calves may sometimes be prey items for lions, spotted hyenas and Nile crocodiles.
Giraffes may flee or act in a non-aggressive manner, while white rhinos typically do not react to the presence of predators. Black and Indian rhinoceroses, elephants, and hippopotamuses on the other hand, react strongly to predators.
Adaptations of extant megaherbivores
Size
Elephants are the largest members, weighing between 2.5 and 6.0 tons. Indian rhinos, white rhinos and hippos usually weigh between 1.4 and 2.3 tons. The Javan and black rhino average 1–1.3 tons in weight. Giraffes are the smallest members, with a general weight range of 0.8–1.2 tons.
K-selection
Extant megaherbivores are K-selected species, meaning they have high life expectancies, slow population growth, large offspring, lengthy pregnancies, and low mortality rates. They have selected slow reproduction to enhance their survival chances, and as a result, increase their lifespan. Their large size offers protection from predators, but at the same, it decreases the degree at which they reproduce due to restricted food sources. This slow population growth (elephants, for example, grow at a rate of 6–7%), indicates that populations may be drastically reduced if predation pressures are too great. In stable environments, K-selection predominates as the ability to compete successfully for limited resources, and populations of K-selected organisms typically are very constant in number and close to the maximum that the environment can bear.
Reproduction
When females enter estrus, males will attempt to attract them as a mating partner. These breeding opportunities may be influenced by the hierarchical system of males. Giraffes and elephants mate for a relatively short time, while rhinos and hippos have a mating session lasting an extended period of time. Females have long gestation periods, between 8 and 22 months. Intervals between births vary between species, but the overall range is 1.3 to 4.5 years.
They usually give birth to a single calf that is heavily reliant on females for food and protection. As they get older, the calf begins weaning while still suckling. When they reach juvenility, they are able to fend for themselves, but only to a certain extent. Females typically separate from their offspring by chasing them. Despite this, females may continue to interact with their progeny even after weaning.
Lifespan and mortality
Hippopotamuses and rhinoceroses can live to be 40 years old, while elephants can live longer than 60 years. Giraffes have a lifespan of around 25 years.
Around 2 to 5% of adult megaherbivores die each year. Males are more likely than females to die from wounds sustained during disputes. Occasionally, in times of drought, populations may significantly reduce, with calves being the most impacted during such times.
See also
Australian megafauna
Deep-sea gigantism
Largest and heaviest animals
List of extant megaherbivores
References
Extinction
Zoology
Animal size
Herbivorous mammals
Ecology
Megafauna | Megaherbivore | [
"Biology"
] | 2,692 | [
"Animal size",
"Zoology",
"Ecology",
"Organism size"
] |
72,285,945 | https://en.wikipedia.org/wiki/L%C3%B6vheim%20Cube%20of%20Emotions | Lövheim Cube of Emotion is a theoretical model for the relationship between the monoamine neurotransmitters serotonin, dopamine and noradrenaline and emotions. The model was presented in 2012 by Swedish researcher Hugo Lövheim.
Lövheim classifies emotions according to Silvan Tomkins, and orders the basic emotions in a three-dimensional coordinate system where the level of the monoamine neurotransmitters form orthogonal axes. The model is regarded as a dimensional model of emotion.
The main concepts of the hypothesis are firstly that the monoamine neurotransmitters are orthogonal variables, meaning involving independent pairs of neurotransmitters; and secondly the proposed one-to-one relationship between the monoamine neurotransmitters and emotions.
References
Psychology articles needing expert attention
Emotion
Mathematical psychology
Affective science | Lövheim Cube of Emotions | [
"Mathematics",
"Biology"
] | 176 | [
"Emotion",
"Behavior",
"Mathematical psychology",
"Applied mathematics",
"Human behavior"
] |
72,286,679 | https://en.wikipedia.org/wiki/Viness%20Pillay | Viness Pillay FAAS (1970–2020) was a South African professor of pharmacy at the University of the Witwatersrand in Johannesburg. He was the Director of the Wits Advanced Drug Delivery Platform (WADDP), a member of African Academy of Sciences, Academy of Translational Medicine Professionals (ATMP) and a beneficiary of the 2013 Olusegun Obasanjo Innovative Award for developing the RapiDiss Wafer Technology as an innovative way to provide effective anti-retroviral (ARV) drug therapy to children afflicted with HIV/AIDS.
Education
He obtained his master's degree in pharmacy from the University of Durban-Westville (South Africa) in 1996 and bagged his PhD at Temple University in 2000 as a Fulbright Scholar.
Scientific contributions
He developed RapiDiss Wafer Technology as an innovative way to provide effective anti-retroviral (ARV) drug therapy to children afflicted with HIV/AIDS. He developed the world's fastest dissolving matrix for the onset of rapid drug action in the human body, a neural device for therapeutic intervention in spinal cord injury and novel wound healing technologies. He also came up with his own molecular modelling paradigms called PEiGOR Theory - Pillay's Electro-influenced Geometrical Organization-Reorganization. This theory was published in the International Journal of Pharmaceutics.
Fellowship and membership
He was elected a Fellow of the Academy of Science of South Africa in 2012. He was also a member of the American Chemical Society, the American Association of Pharmaceutical Scientists, the New York Academy of Sciences, the Academy of Pharmaceutical Sciences of South Africa, and The Biomaterials Network.
Awards and honours
He was a beneficiary of National Research Foundation (NRF) Awards.
Death
Pillay died on 24 July 2020 after a lengthy illness. He left behind a wife and a daughter.
References
University of Durban-Westville alumni
Pharmacologists
1970 births
2020 deaths
Fellows of the African Academy of Sciences | Viness Pillay | [
"Chemistry"
] | 406 | [
"Pharmacology",
"Biochemists",
"Pharmacologists"
] |
72,287,044 | https://en.wikipedia.org/wiki/Grimpoteuthis%20angularis | Grimpoteuthis angularis is a species of octopus in the family Grimpoteuthidae. It was first described by Tristan J Verhoeff and Steve O'Shea in 2022, based on a single specimen found in New Zealand.
Taxonomy
The species was given the name angularis, referring to the octopus' angled shell. Verhoeff & O'Shea proposed that the common name of the species should be angle-shelled dumbo octopus. This species (as well as other Grimpoteuthis) may belong in its own family, the Grimpoteuthididae.
Description and habitat
The shell of Grimpoteuthis angularis is V-shaped, notably different to other Grimpoteuthis; the relatively elongate cirri are also distinctive. The holotype was discovered on the Chatham Rise to the east of New Zealand, at a depth of 628 metres.
References
Cephalopods of Oceania
Endemic fauna of New Zealand
Endemic molluscs of New Zealand
Fauna of the Chatham Islands
Cephalopods described in 2022
Molluscs of New Zealand
Molluscs of the Pacific Ocean
Octopuses
Species known from a single specimen | Grimpoteuthis angularis | [
"Biology"
] | 242 | [
"Individual organisms",
"Species known from a single specimen"
] |
72,287,199 | https://en.wikipedia.org/wiki/CYP109B1 | Cytochrome P450 family 109 subfamily B member 1 (abbreviated CYP109B1) is a versatile prokaryote monooxygenase of CYP109 family originally from Bacillus subtilis, its three-dimensional protein crystal structure has been solved.
References
Cytochrome P450
Prokaryote genes | CYP109B1 | [
"Biology"
] | 72 | [
"Prokaryotes",
"Prokaryote genes"
] |
72,287,653 | https://en.wikipedia.org/wiki/CYP109E1 | Cytochrome P450 family 109 subfamily E member 1 (abbreviated CYP109E1) is a prokaryote monooxygenase of CYP109 family originally from Bacillus megaterium, could atc as a 24- and 25-Hydroxylase for Cholesterol.
References
Cytochrome P450
Prokaryote genes | CYP109E1 | [
"Biology"
] | 78 | [
"Prokaryotes",
"Prokaryote genes"
] |
72,287,736 | https://en.wikipedia.org/wiki/Landau%20kernel | The Landau kernel is named after the German number theorist Edmund Landau. The kernel is a summability kernel defined as:
where the coefficients are defined as follows:
Visualisation
Using integration by parts, one can show that:
Hence, this implies that the Landau kernel can be defined as follows:
Plotting this function for different values of n reveals that as n goes to infinity, approaches the Dirac delta function, as seen in the image, where the following functions are plotted.
Properties
Some general properties of the Landau kernel is that it is nonnegative and continuous on . These properties are made more concrete in the following section.
Dirac sequences
The third bullet point means that the area under the graph of the function becomes increasingly concentrated close to the origin as n approaches infinity. This definition lends us to the following theorem.
Proof: We prove the third property only. In order to do so, we introduce the following lemma:
Proof of the Lemma:
Using the definition of the coefficients above, we find that the integrand is even, we may writecompleting the proof of the lemma. A corollary of this lemma is the following:
See also
Poisson kernel
Fejér kernel
Dirichlet kernel
References
Mathematical analysis | Landau kernel | [
"Mathematics"
] | 251 | [
"Mathematical analysis"
] |
58,390,130 | https://en.wikipedia.org/wiki/Standard%20SC%20engine | The Standard SC engine is a cast-iron overhead valve straight-four engine designed and initially produced by Standard Triumph. Over its production life displacement grew from an initial size of just over 800 cc to nearly 1500 cc. Introduced in the Standard Eight in 1953, it would eventually be used in a wide range of vehicles from Standard, Triumph, and MG.
Origin
In 1948 a "single model" policy was instituted at Standard, centred on the Standard Vanguard. Standard Triumph chairman John Black nevertheless wanted to add a new model below the existing Vanguard in the company's lineup, and so work had started in 1950/1951 on a new car and engine to power it, both of which were named "SC" for "small car". The car would face competition in the marketplace from the recently introduced Ford Anglia, Austin A30, and Morris Minor. Consideration was given to using the existing Vanguard engine, but this linered engine was considered too expensive for the intended market. The engine designed for the new small car would use the tooling installed to produce the engine for the Triumph Mayflower, and so would have to have the same bore centres as that earlier design. Austin's new A-series engine and the original Standard SC shared the same bore and stroke and displacement, leading some to wonder if Standard engineers had copied the Austin design for their own. Other significant differences between the engines, including the number and placement of intake and exhaust ports and the ability of the SC to be expanded to nearly 1.5 L, make this unlikely.
Model history
800
The new engine first appeared in the Standard Eight in 1953. With a displacement of the engine produced at 4500 rpm. By 1957 power had increased to at 5000 rpm.
950
In 1954 the Standard Ten was introduced as a more well-appointed version of the Standard Eight, while sharing the earlier car's frame and transmission. The engine for the Ten was enlarged to and developed . By the time the Standard Pennant, a revised Ten with tail-fins and optional two-tone paint schemes, was launched in October 1957, output of the 948 cc engine had increased to .
The first engine offered in the Triumph Herald was also the 948 cc SC. Power was claimed to be .
1150
Standard-Triumph was taken over by Leyland Motors in 1961, which made available new resources to develop the Herald. The car was re-launched in April 1961 with an engine as the Herald 1200. To gain the extra displacement the cylinders were placed out of centre which cleared the studs so that a bigger bore could be used. Twin carburettors were no longer standard fitment to any of the range, although they remained an option. The standard was a single down-draught Solex carburettor. Claimed maximum power of the Herald 1200 was . An upmarket version, the Herald 12/50, was offered from 1963 to 1967 and featured a tuned engine with a claimed output of .
The 1147 cc version of the engine was also used in the first model of the Triumph Spitfire. Mildly tuned and fed by twin SU carburettors, in UK tune the in-line four produced at 5,750 rpm, and of torque at 3,500 rpm.
A special light-alloy 8-port racing cylinder head used on the later Le Mans and Macau Spitfires' 1147 cc engines was labelled "70X". A version of this head for the later 1296 cc engine was labelled "79X", the numbers representing the displacement of the engines in cubic inches.
1300
In 1965 the engine was enlarged from 1147 cc to , with the increase coming from a change in bore from to while stroke remained at . This version was fitted to the new Triumph Herald 13/60 and Triumph 1300 saloons. When it debuted in the Triumph 1300 with a single Stromberg CD150 carburettor it developed due to the adoption of the German DIN rating system; the actual output was the same for the early Mark IV. The less powerful North American version still used a single Zenith Stromberg carburettor and an 8.5:1 compression ratio. Displacement remained at 1296 cc, but in 1973 larger big-end bearings were fitted to rationalize production with the TR6 2.5 L engines, which somewhat dampened its previously high-revving nature. Some detuning was also done to meet new emissions laws.
1500
Another change to the SC inline 4 came in 1970 when its stroke was increased from to , increasing displacement to . Debuting in the front-wheel drive Triumph 1500 with a single SU carburettor, power output was . Later used in the Triumph Spitfire 1500, this final incarnation of the engine was rather rough and more prone to failure than the earlier models, although torque was greatly increased. While most export-market Spitfire 1500s had a compression ratio reduced to 8.0:1, the American market model was fitted with a single Zenith-Stromberg carburettor and a compression ratio reduced to 7.5:1 to allow it to run on lower octane unleaded fuel. After adding a catalytic converter and exhaust gas recirculating system, the US market engine only delivered . The notable exception to this was the 1976 model year, when the compression ratio was raised to 9.1:1. This improvement was short-lived, however, as the ratio was again reduced to 7.5:1 for the remaining years of production.
The UK received the most powerful variant of all. Aided by a 9:1 compression ratio, less restrictive emissions control equipment, and two Type HS4 SU carburettors in place of the smaller Type HS2s, the Spitfire 1500 engine produced at 5,500 rpm, and of torque at 3,000 rpm.
The 1500 engine was also used in the MG Midget 1500 (1974–80) coupled to a modified Morris Marina gearbox.
Design
Design of the engine was headed by David Eley, a long-time Standard employee. The engine had a cast-iron block and cylinder head, and a pressed-steel sump. Spark-plugs and camshaft were on the left side of the engine, while the inlet and exhaust manifolds were on the right. The camshaft, which drove the distributor and oil pump through a spur gear, was itself chain-driven off the nose of the crankshaft, with the drive covered by a pressed-steel cover. The cylinder head had four inlet and four outlet ports, in contrast to some of its competitors who had some ports siamesed. The crankshaft was carried in three main bearings. Crankshaft and connecting rods were steel, while the pistons were light alloy. The ancillaries were mounted on the left side of the engine, while the water pump and thermostat were in a separate casting attached to the front of the engine.
Inline 6
An inline six cylinder engine was developed from the SC four. The Standard Triumph Six first appeared in 1960 in the Standard Vanguard Six. It had a bore and a stroke, giving a capacity of .
The engine was next used in the Triumph Vitesse, a sports saloon based on the Herald, in 1962. In this application the engine had a bore, reducing displacement to . The Vitesse got the 2 L engine in 1966.
The Triumph 2000 replaced the Vanguard Six in 1963 when Leyland discontinued the Standard marque. The 2 L six was later used in the Spitfire-based GT6 coupé from 1966 to 1974.
In 1967 the engine replaced the Standard inline-four in the new Triumph TR5 and TR250 models. For this application the stroke was increased to , raising displacement to .
This engine was succeeded by the Leyland PE 146 and PE 166 engines designed by Triumph for the new Rover SD1. Although the earliest proposals for this project were for a new overhead camshaft cylinder-head on the original block, limitations in the Triumph block caused this option to be rejected, and the new OHC six shared no parts with the old Triumph engine.
Replacement
Although never directly replaced by another engine in the Triumph Spitfire, the SC was superseded by the Triumph slant-four as the premier power unit in the higher specification Dolomites.
References
Automobile engines
Triumph Motor Company engines
Straight-four engines
Gasoline engines by model | Standard SC engine | [
"Technology"
] | 1,674 | [
"Engines",
"Automobile engines"
] |
58,397,660 | https://en.wikipedia.org/wiki/Aspergillus%20aculeatinus | Aspergillus aculeatinus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli, which are important industrial workhorses.
A. aculeatinus belongs to the Nigri section. The species was first described in 2008
and has been isolated from Thai coffee beans. It has been shown to produce neoxaline, secalonic acid D and F, and aculeacins.
The genome of A. aculeatinus was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 36.47 Mbp.
Growth on agar plates
Apsergillus aculeatinus has been cultivated on Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
aculeatinus
Parasitic fungi
Fungi described in 2008
Fungus species | Aspergillus aculeatinus | [
"Biology"
] | 231 | [
"Fungi",
"Fungus species"
] |
58,397,951 | https://en.wikipedia.org/wiki/Cobalt%28III%29%20chloride | Cobalt(III) chloride or cobaltic chloride is an unstable and elusive compound of cobalt and chlorine with formula . In this compound, the cobalt atoms have a formal charge of +3.
The compound has been reported to exist in the gas phase at high temperatures, in equilibrium with cobalt(II) chloride and chlorine gas. It has also been found to be stable at very low temperatures, dispersed in a frozen argon matrix.
Some articles from the 1920s and 1930s claim the synthesis of bulk amounts of this compound in pure form; however, those results do not seem to have been reproduced, or have been attributed to other substances like the hexachlorocobaltate(III) anion . Those earlier reports claim that it gives green solutions in anhydrous solvents such as ethanol and diethyl ether, and that it is stable only a very low temperatures (below −60 °C).
Structure and properties
The infrared spectrum of the compound in frozen argon indicates that the isolated molecule is planar with D3h symmetry.
A Scientific study of the stability of this and other metal trihalides at 50 °C was published by Nelsoon and Sharpe in 1956.
Aerodynamic properties for the gas phase have been determined by the Glushko Thermocenter of the Russian Academy of Sciences.
Preparation
Cobalts trichloride was detected in 1952 by Schäfer and Krehl in the gas phase when cobalt(II) chloride is heated in an atmosphere of chlorine . The trichloride is formed through the equilibrium
2 + ↔ 2
At 918 K (below the melting point of , 999 K), the trichloride was the predominant cobalt species in the vapor, with partial pressure of 0.72 mm Hg versus 0.62 for the dichloride. However, equilibrium shifts to the left at higher temperatures. At 1073 K, the partial pressures were 7.3 and 31.3 mm Hg, respectively.
Cobalt trichloride, in amounts sufficient to study spectroscopically, was obtained by Green and others in 1983, by sputtering cobalt electrodes with chlorine atoms and trapping the resulting molecules in frozen argon at 14 K.
A report from 1969 claims that treatment of solid cobalt(III) hydroxide · with anhydrous ether saturated with at −20 °C produces a green solution (stable at −78 °C) with the characteristic spectrum of .
In a 1932 report, the compound was claimed to arise in the electrolysis of cobalt(II) chloride in anhydrous ethanol.
Related compounds
The hexachlorocobaltate(III) anion has been identified in preparations of cobalt(III) salts and hydrochloric acid in glacial acetic acid.
In solutions of cobalt(III) salts with chloride ions, the anionic complexes and are present.
Trichlorides of cobalt(III) complexed with various ligands, such as organic amines, can be quite stable. In particular, hexamminecobalt(III) chloride is the archetypal Werner complex and has uses in biological research. Another classical example is tris(ethylenediamine)cobalt(III) chloride .
References
Cobalt(III) compounds
Inorganic compounds
Chlorides
Metal halides | Cobalt(III) chloride | [
"Chemistry"
] | 673 | [
"Chlorides",
"Inorganic compounds",
"Metal halides",
"Salts"
] |
58,398,703 | https://en.wikipedia.org/wiki/Aspergillus%20ellipticus | Aspergillus ellipticus (also named A. helicothrix) is a species of fungus in the genus Aspergillus. A. ellipticus belongs to the group of black Aspergilli, which are important industrial workhorses. A. ellipticus belongs to the Nigri section. The species was first described in 1965, and has been shown to produce sclerotia.
The genome of A. ellipticus was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the Aspergillus genus. The genome assembly size was 42.87 Mbp.
Growth and morphology
Aspergillus ellipticus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
ellipticus
Fungi described in 1965
Fungus species | Aspergillus ellipticus | [
"Biology"
] | 210 | [
"Fungi",
"Fungus species"
] |
58,398,796 | https://en.wikipedia.org/wiki/Aspergillus%20eucalypticola | Aspergillus eucalypticola is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. eucalypticola belongs to the Nigri section.
The species was first described in 2011. A. aculeatinus has been isolated from eucalyptus leaves in Australia, and has been shown to produce pyranonigrin A, funalenone, aurasperone B and other naphtho-γ-pyrones.
The genome of A. eucalypticola was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the Aspergillus genus. The genome assembly size was 34.79 Mbp.
Growth and morphology
Aspergillus eucalypticola has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
eucalypticola
Fungi described in 2011
Fungus species | Aspergillus eucalypticola | [
"Biology"
] | 249 | [
"Fungi",
"Fungus species"
] |
58,398,810 | https://en.wikipedia.org/wiki/Aspergillus%20fijiensis | Aspergillus fijiensis is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. fijiensis belongs to the Nigri section.
The species was first described in 2011. It has been isolated from soil in Fiji and from Lactuca sativa in Indonesia. This species is able to grow at 37 °C, and produces asperparalines and okaramins.
The genome of A. fijiensis was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 36.51 Mbp.
Growth and morphology
A. fijiensis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
fijiensis
Fungi described in 2011
Fungus species | Aspergillus fijiensis | [
"Biology"
] | 222 | [
"Fungi",
"Fungus species"
] |
58,399,501 | https://en.wikipedia.org/wiki/Aspergillus%20heteromorphus | Aspergillus heteromorphus is a species of fungus in the genus Aspergillus. A. heteromorphus belongs to the group of black Aspergilli which are important industrial workhorses. A. heteromorphus belongs to the Nigri section. The species was first described in 1957. The species has been found in Brazil. It has been isolated from both rice straws, wheat straws, and sugarcane bagasse. This species can produce sclerotia and some mid-polar indole compounds. It produces a series of other not well-characterized exometabolites.
The genome of A. heteromorphus was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 35.61 Mbp.
Growth and morphology
Aspergillus heteromorphus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
heteromorphus
Fungi described in 1957
Fungus species | Aspergillus heteromorphus | [
"Biology"
] | 266 | [
"Fungi",
"Fungus species"
] |
58,399,541 | https://en.wikipedia.org/wiki/Aspergillus%20homomorphus | Aspergillus homomorphus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. homomorphus belongs to the Nigri section. The species was first described in 1995. It has been isolated from soil from the Dead Sea in Israel. The mycotoxin secalonic acid D has been reported from this fungus. In addition, it produces many exometabolites only found in this fungus.
The genome of A. homomorphus was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 34.05 Mbp.
Growth and morphology
Aspergillus homomorphus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
homomorphus
Fungi described in 2004
Fungus species | Aspergillus homomorphus | [
"Biology"
] | 242 | [
"Fungi",
"Fungus species"
] |
58,399,658 | https://en.wikipedia.org/wiki/Aspergillus%20indologenus | Aspergillus indologenus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. indologenus belongs to the Nigri section. The species was first described in 2011. It was isolated from soil in India and found to produce insecticidal compounds okaramins A, B, H, and two types of indol-alkaloids which have not been structure elucidated.
The genome of A. indologenus was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 38.59 Mbp.
Growth and morphology
Aspergillus indologenus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
indologenus
Parasitic fungi
Fungi described in 2011
Fungus species | Aspergillus indologenus | [
"Biology"
] | 241 | [
"Fungi",
"Fungus species"
] |
58,399,818 | https://en.wikipedia.org/wiki/Aspergillus%20lacticoffeatus | Aspergillus lacticoffeatus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. lacticoffeatus belongs to the Nigri section. It was first described in 2004. It has been found on coffee beans in Venezuela and Indonesia, and is an effective producer of ochratoxin. It has an unfunctional PKS gene (pksA) for the production of black conidium pigment, which makes it the only species in the Nigri section which is brown and not black. It has been proposed that this species might not be a separate species but instead a mutated A. niger.
The genome of A. lacticoffeatus was sequenced in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. Its genome assembly size was 35.86 Mbp.
Growth and morphology
Aspergillus lacticoffeatus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
lacticoffeatus
Fungi described in 2004
Fungus species | Aspergillus lacticoffeatus | [
"Biology"
] | 284 | [
"Fungi",
"Fungus species"
] |
58,400,279 | https://en.wikipedia.org/wiki/Streptomyces-metKH%20RNA%20motif | A Streptomyces-metKH RNA motif is a conserved RNA structure that was discovered by bioinformatics.
Such motifs are found in the genus Streptomyces, and are present upstream of either metK genes, which encode the S-adenosylmethionine synthetase enzyme or metH genes, which encodes the adenosylcobalamin-dependent form of methionine synthase. The RNA structures upstream of metK and metH genes are distinct from each other, but exhibit overall similar sequence and secondary structure features, suggesting that they are related to one another. Their presence upstream of protein-coding genes, and the fact that the genes perform related steps in metabolism, suggests that the RNAs function as cis-regulatory elements.
References
Non-coding RNA | Streptomyces-metKH RNA motif | [
"Chemistry"
] | 167 | [
"Molecular biology stubs",
"Molecular biology"
] |
58,400,340 | https://en.wikipedia.org/wiki/CNS%20%28chemical%20weapon%29 | CNS is a mixture of chloroacetophenone, chloropicrin and chloroform that is used as a chemical warfare agent. CNS has the lachrymatory effects of chloroacetophenone and choking effects of chloropicrin. It has a flypaper-like odor.
CNS was used as a riot control agent, but it is no longer used.
References
Chemical weapons
Lachrymatory agents
Chemical warfare agent mixtures | CNS (chemical weapon) | [
"Chemistry",
"Biology"
] | 102 | [
"Chemical accident",
"Chemical weapons",
"Chemical warfare agent mixtures",
"Lachrymatory agents",
"Biochemistry"
] |
58,400,717 | https://en.wikipedia.org/wiki/Aspergillus%20luchuensis | Aspergillus luchuensis (previous names A. foetidus and A. acidus) is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. The fungus has been used to make awamori, a distilled spirit in Okinawa Island, Japan, and is also used to make shōchū and sake. This species was first isolated and described by Tamaki Inui of the University of Tokyo in 1901. For more than 100 years there has been confusion between this species and Aspergillus awamori and Aspergillus niger with regard to scientific names and classification.
The scientific name for this species is derived from "Ryukyu", the historical name for Okinawa, Japan. It is authorized as a along with Aspergillus oryzae, Aspergillus sojae and Aspergillus kawachii by the Scientific Conference of Brewing Society Japan because it is used not only in brewing but also in a variety of foods and is useful in the lives of Japanese people.
In 1918, Genichiro Kawachi isolated an albino mutant of Aspergillus luchuensis (black kōji) and named it Aspergillus kawachii (white kōji). This mutant is now also called Aspergillus luchuensis mut. kawachii. In shōchū brewing, Aspergillus oryzae (yellow kōji) was traditionally used, but black and white kōji produced more citric acid and were more effective in preventing microorganism growth, so the use of black kōji was recommended from the 1940s and white kōji from the 1950s. Brewing with each type of kōji brings different flavors to shōchū. Sake was also traditionally brewed with yellow kōji, but from the 21st century sake brewed with white or black kōji began to appear. The black kōji variants and white kōji that Kawachi discovered and isolated have been used in makgeolli and soju in Korea since the 1940s.
Its genome has been sequenced by two different research groups, first in 2016, and then in 2017. The first sequencing of the A. luchuensis genome reported a genome assembly size of 34.7 Mbp and reported the presence of 11,691 genes.
See also
Aspergillus awamori
References
luchuensis
Fungi described in 1901
Fungus species | Aspergillus luchuensis | [
"Biology"
] | 509 | [
"Fungi",
"Fungus species"
] |
58,400,882 | https://en.wikipedia.org/wiki/Aspergillus%20neoniger | Aspergillus neoniger is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. neoniger belongs to the Nigri section. The species was first described in 2011. The species was isolated from desert sand in Namibia and mangrove water in Venezuela. A. neoniger produces aurasperone B and pyranonigrin A.
The genome of A. neoniger was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 35.42 Mbp.
Growth and morphology
Aspergillus neoniger has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
neoniger
Fungi described in 2011
Fungus species | Aspergillus neoniger | [
"Biology"
] | 217 | [
"Fungi",
"Fungus species"
] |
58,401,424 | https://en.wikipedia.org/wiki/Aspergillus%20piperis | Aspergillus piperis is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. piperis belongs to the Nigri section and was first described in 2004. It was isolated from black ground pepper and produced large yellow to pink brown sclerotia.
The genome of A. piperis was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 35.28 Mbp.
Growth and morphology
Aspergillus piperis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
piperis
Fungi described in 2004
Fungus species | Aspergillus piperis | [
"Biology"
] | 201 | [
"Fungi",
"Fungus species"
] |
58,401,547 | https://en.wikipedia.org/wiki/Aspergillus%20sclerotiicarbonarius | Aspergillus sclerotiicarbonarius is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. sclerotiicarbonarius belongs to the Nigri section. The species was first described in 2008. It has been isolated from Thai coffee beans.
The genome of A. sclerotiicarbonarius was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 37.62 Mbp.
Growth and morphology
Aspergillus sclerotiicarbonarius has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
sclerotiicarbonarius
Fungi described in 2008
Fungus species | Aspergillus sclerotiicarbonarius | [
"Biology"
] | 218 | [
"Fungi",
"Fungus species"
] |
58,401,614 | https://en.wikipedia.org/wiki/Aspergillus%20sclerotioniger | Aspergillus sclerotioniger is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. sclerotioniger belongs to the Nigri section. The species was first described in 2004. It has been found in green coffee beans from India. It is a very effective producer of ochratoxin A and ochratoxin B, and produces aurasperone B, pyranonigrin A, corymbiferan lactone-like exometabolites, and some cytochalasins. The genome of A. sclerotioniger was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 36.72 Mbp.
Growth and morphology
Aspergillus sclerotioniger has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
sclerotioniger
Fungi described in 2004
Fungus species | Aspergillus sclerotioniger | [
"Biology"
] | 265 | [
"Fungi",
"Fungus species"
] |
58,402,003 | https://en.wikipedia.org/wiki/Scramspace | Scramspace was a hypersonic engine research project established by the University of Queensland, Australia's Centre for Hypersonics. It was a 1.8 meter long, free-flying, hypersonic scramjet. A scramjet is fundamentally an air-breathing engine that travels at hypersonic velocities. Built in Brisbane at an estimated cost of $14 million, it took approximately 3 years to complete. Scramspace was supposed to fire at a hypersonic velocity of Mach 8 or 8600 km/hour (5343 mph) but the flight-test turned out to be a failure and the rocket engine and the payload plummeted in the North Sea off the coast of Norway.
Background
Scramspace was designed and built at Brisbane, Australia. It took 3 years to build and was estimated to cost around $14 million. It was approximated to fly at around Mach 8. It was the first and the largest research project funded by the Australian Space Research Program. A number of ground-based research tests and Mach 8 flight experiments were involved to establish the research project. A number of engineers and PhD scholars were involved in the making of this project.
Ground tests up to Mach 14 were performed to assess the scientific and technical parameters of the project. This was followed by flight tests up to Mach 8.
The project involved five countries in partnership: Australia, Japan, Germany, Italy, and the United States. It was led by the University of Queensland's Center for Hypersonics.
Aftermath
In August 2013, the scramjet was airlifted to Norway for a final flight test at Mach 8. The engine was fabricated to reach an altitude of about 340 km( 211.266 miles) with the help of a two- stage rocket engine.
According to the experiment, on leaving the atmosphere, the scramjet had to separate from the rocket engine and re-orient itself for reentry. The flight -sensor data had to be collected in a three-second window before the scramjet disintegrated on reentry.
However, because of some unknown issue in the first stage rocket motor, the scramjet payload could not be delivered to the correct altitude and speed in the flight test conducted on September 18, 2013.
The uncrewed spacecraft with the payload and the rocket plummeted in the North Sea off the cost of Norway.
Results
The final stage of the project did not yield any hypersonic flight data. However, the ground testing, modelling and analysis were able to provide reference results for future projects. The project provided valuable insight and results pertaining to hypersonic physics, hypersonic combustion, and the performance of materials and components. It set an example for future hypersonic aircraft research.
References
Aerospace engineering
University of Queensland | Scramspace | [
"Engineering"
] | 560 | [
"Aerospace engineering"
] |
58,402,119 | https://en.wikipedia.org/wiki/Aspergillus%20uvarum | Aspergillus uvarum is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. uvarum belongs to the Nigri section. The species was first described in 2008. A. uvarum has been isolated from grapes in Europe. It has been shown to produce secalonic acid, which is common for other black aspergilli; and geodin, erdin, and dihydrogeodin, which are not produced by any other black aspergilli.
The genome of A. uvarum was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 35.85 Mbp. A. uvarum has 12,347 genes.
Growth and morphology
Aspergillus uvarum has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
uvarum
Fungi described in 2008
Fungus species | Aspergillus uvarum | [
"Biology"
] | 264 | [
"Fungi",
"Fungus species"
] |
58,402,255 | https://en.wikipedia.org/wiki/Aspergillus%20violaceofuscus | Aspergillus violaceofuscus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. violaceofuscus belongs to the Nigri section. The species was first described in 1887. It has been found both in marine environments in Bahamas and in soil in Puerto Rico. The genome of A. violaceofuscus was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 36.01 Mbp.
Growth and morphology
A. violaceofuscus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
violaceofuscus
Fungi described in 1887
Fungus species | Aspergillus violaceofuscus | [
"Biology"
] | 214 | [
"Fungi",
"Fungus species"
] |
58,402,395 | https://en.wikipedia.org/wiki/Reachability%20analysis | Reachability analysis is a solution to the reachability problem in the particular context of distributed systems. It is used to determine which global states can be reached by a distributed system which consists of a certain number of local entities that communicated by the exchange of messages.
Overview
Reachability analysis was introduced in a paper of 1978 for the analysis and verification of communication protocols. This paper was inspired by a paper by Bartlett et al. of 1968 which presented the alternating bit protocol using finite-state modeling of the protocol entities, and also pointed out that a similar protocol described earlier had a design flaw. This protocol belongs to the Link layer and, under certain assumptions, provides as service the correct data delivery without loss nor duplication, despite the occasional presence of message corruption or loss.
For reachability analysis, the local entities are modeled by their states and transitions. An entity changes state when it sends a message, consumes a received message, or performs an interaction at its local service interface. The global state of a system with n entities is determined by the states (i=1, ... n) of the entities and the state of the communication . In the simplest case, the medium between two entities is modeled by two FIFO queues in opposite directions, which contain the messages in transit (that are sent, but not yet consumed). Reachability analysis considers the possible behavior of the distributed system by analyzing all possible sequences of state transitions of the entities, and the corresponding global states reached.
The result of reachability analysis is a global state transition graph (also called reachability graph) which shows all global states of the distributed system that are reachable from the initial global state, and all possible sequences of send, consume and service interactions performed by the local entities. However, in many cases this transition graph is unbounded and can not be explored completely. The transition graph can be used for checking general design flaws of the protocol (see below), but also for verifying that the sequences of service interactions by the entities correspond to the requirements given by the global service specification of the system.
Protocol properties
Boundedness: The global state transition graph is bounded if the number of messages that may be in transit is bounded and the number states of all entities is bounded. The question whether the number of messages remains bounded in the case of finite state entities is in general not decidable. One usually truncates the exploration of the transition graph when the number of messages in transit reaches a given threshold.
The following are design flaws:
Global deadlock: The system is in a global deadlock if all entities wait for the consumption of a message and no message is in transit. Absence of global deadlocks can be verified by checking that no state in the reachability graph is a global deadlock.
Partial deadlocks: An entity is in a deadlocked state if it waits for the consumption of a message and the system is in a global state where such a message is not in transit and will never be sent in any global state that can be reached in the future. Such a non-local property can be verified by performing model checking on the reachability graph.
Unspecified reception: An entity has an unspecified reception if the next message to be consumed is not expected by the behavior specification of the entity in its current state. The absence of this condition can be verified by checking all states in the reachability graph.
An example
As an example, we consider the system of two protocol entities that exchange the messages ma, mb, mc and md with one another, as shown in the first diagram. The protocol is defined by the behavior of the two entities, which is given in the second diagram in the form of two state machines. Here the symbol "!" means sending a message, and "?" means consuming a received message. The initial states are the states "1".
The third diagram shows the result of the reachability analysis for this protocol in the form of a global state machine. Each global state has four components: the state of protocol entity A (left), the state of the entity B (right) and the messages in transit in the middle (upper part: from A to B; lower part: from B to A). Each transition of this global state machine corresponds to one transition of protocol entity A or entity B. The initial state is [1, - - , 1] (no messages in transit).
One sees that this example has a bounded global state space - the maximum number of messages that may be in transit at the same time is two. This protocol has a global deadlock, which is the state [2, - - , 3]. If one removes the transition of A in state 2 for consuming message mb, there will be an unspecified reception in the global states [2, ma mb ,3] and [2, - mb ,3].
Message transmission
The design of a protocol has to be adapted to the properties of the underlying communication medium, to the possibility that the communication partner fails, and to the mechanism used by an entity to select the next message for consumption. The communication medium for protocols at the Link level is normally not reliable and allows for erroneous reception and message loss (modeled as a state transition of the medium). Protocols using the Internet IP service should also deal with the possibility of out-of-order delivery. Higher-level protocols normally use a session-oriented Transport service which means that the medium provides reliable FIFO transmission of messages between any pair of entities. However, in the analysis of distributed algorithms, one often takes into account the possibility that some entity fails completely, which is normally detected (like a loss of message in the medium) by a timeout mechanism when an expected message does not arrive.
Different assumptions have been made about whether an entity can select a particular message for consumption when several messages have arrived and are ready for consumption. The basic models are the following:
Single input queue: Each entity has a single FIFO queue where incoming messages are stored until they are consumed. Here the entity has no selection power and has to consume the first message in the queue.
Multiple queues: Each entity has multiple FIFO queues, one for each communicating partner. Here the entity has the possibility to decide, depending on its state, from which queue (or queues) the next input message should be consumed.
Reception pool: Each entity has a single pool where received messages are stored until they are consumed. Here the entity has the power to decide, depending on its state, which type of message should be consumed next (and wait for a message if none has been received yet), or possibly consume one from a set of message types (in order to deal with alternatives).
The original paper identifying the problem of unspecified receptions, and much of the subsequent work, assumed a single input queue. Sometimes, unspecified receptions are introduced by a race condition, which means that two messages are received and their order is not defined (which is often the case if they come from different partners). Many of these design flaws disappear when multiple queues or reception pools are used. With the systematic use of reception pools, reachability analysis should check for partial deadlocks and messages remaining forever in the pool (without being consumed by the entity)
Practical issues
Most of the work on protocol modeling use finite-state machines (FSM) to model the behavior of the distributed entities (see also Communicating finite-state machines). However, this model is not powerful enough to model message parameters and local variables. Therefore often so-called extended FSM models are used, such as supported by languages like SDL or UML state machines. Unfortunately, reachability analysis becomes much more complex for such models.
A practical issue of reachability analysis is the so-called ″state space explosion″. If the two entities of a protocol have 100 states each, and the medium may include 10 types of messages, up to two in each direction, then the number of global states in the reachability graph is bound by the number 100 x 100 x (10 x 10) x (10 x 10) which is 100 million. Therefore a number of tools have been developed to automatically perform reachability analysis and model checking on the reachability graph. We mention only two examples: The SPIN model checker and a toolbox for the construction and analysis of distributed processes.
Further reading
Communication protocols
Gerald Holzmann: Design and Validation of Computer Protocols, Prentice Hall, 1991.
G.v. Bochmann, D. Rayner and C.H. West: Some notes on the history of protocol engineering, Computer Networks journal, 54 (2010), pp 3197–3209.
References and notes
Theory of computation | Reachability analysis | [
"Technology"
] | 1,763 | [
"Computer standards",
"Communications protocols"
] |
58,402,686 | https://en.wikipedia.org/wiki/Michell%20structures | Michell structures are structures that are optimal based on the criteria defined by A.G.M. Michell in his frequently referenced 1904 paper.
Michell states that “a frame (today called truss) (is optimal) attains the limit of economy of material possible in any frame-structure under the same applied forces, if the space occupied by it can be subjected to an appropriate small deformation, such that the strains in all the bars of the frame are increased by equal fractions of their lengths, not less than the fractional change of length of any element of the space.”
The above conclusion is based on the Maxwell load-path theorem:
Where is the tension value in any tension element of length , is the compression value in any compression element of length and is a constant value which is based on external loads applied to the structure.
Based on the Maxwell load-path theorem, reducing load path of tension members will reduce by the same value the load path of compression elements for a given set of external loads. Structure with minimum load path is one having minimum compliance (having minimum weighted deflection in the points of applied loads weighted by the values of these loads). In consequence Michell structures are minimum compliance trusses.
Special cases
1. All bars of a truss are subject to a load of the same sign (tension or compression).
Required volume of material is the same for all possible cases for a given set of loads. Michell defines minimum required volume of material to be:
Where is the allowable stress in the material.
2. Mixed tension and compression bars
More general case are frames which consist of bars that both before and after the appropriate deformation, form curves of orthogonal systems. A two-dimensional orthogonal system remains orthogonal after stretching one series of curves and compressing the other with equal strain if and only if the inclination between any two adjacent curves of the same series is constant throughout their length. This requirement results with the perpendicular series of curves to be either:
a) systems of tangents and involutes or
b) systems of intersecting logarithmic spirals.
Note that straight line or a circle are special cases of a logarithmic spiral.
Examples
Michell provided several examples of optimum frames:
Prager trusses
In recent years a lot of studies have been done on discrete optimum trusses. In spite of Michell trusses being defined for continuum (infinite number of members) these are sometimes called Michell trusses as well. Significant contribution to the topic of discrete optimum trusses had William Prager who used the method of the circle of relative displacements to arrive with optimal topology of such trusses (typically cantilevers). To recognize Prager's contribution discrete Michell trusses are sometimes called Prager trusses. Later geometry of cantilevered Prager trusses has been formalized by Mazurek, Baker and Tort who noticed certain geometrical relationships between members of optimal discrete trusses for 3 point or 3 force problems.
References
Structural analysis | Michell structures | [
"Engineering"
] | 610 | [
"Structural engineering",
"Structural analysis",
"Mechanical engineering",
"Aerospace engineering"
] |
58,403,719 | https://en.wikipedia.org/wiki/Bathroom%20reading | Bathroom reading is the act of reading text while in a bathroom, usually while sitting on the toilet and defecating. The practice has been common throughout history and remains widespread today with both printed material and smartphones.
History
Bathroom reading has been commonplace throughout history. Before the invention of modern toilet paper, Americans in the colonial period often used newspaper or similar printed material to wipe themselves, because newsprint paper is fairly soft and absorbent. Writing in the 18th century, the English statesman Philip Stanhope, 4th Earl of Chesterfield reported that he knew "a gentleman who was so good a manager of his time that he would not even lose that small portion of it which the call of nature obliged him to pass in the necessary-house; but gradually went through all the Latin poets, in those moments.
The advent of the mobile phone is believed to have significantly increased bathroom reading. A 2009 study conducted in Israel found that a majority of adults read from their cell phones on the toilet, and a 2015 study conducted by Verizon found that 90% of cell phone users admitted to reading from their phones while on the toilet.
Bathroom reading and literature
The term "bathroom reading" refers to any literary material deemed suitable for casual or light reading. In 2011, the Canadian author Margaret Atwood wrote:
Pulp magazines were associated with bathroom reading, which the film Pulp Fiction references in repeated scenes of John Travolta's character Vincent Vega reading the pulpy spy novel Modesty Blaise while sat on a toilet. Bathroom reading also refers to a genre of books containing humor and trivia, such as the Uncle John's Bathroom Reader series.
In James Joyce's novel Ulysses, the protagonist Leopold Bloom reads a magazine on the toilet and then wipes himself with it.
Sanitation, hygiene and health
According to a professor at the Columbia University Medical Center, reading in the bathroom can potentially facilitate the spread of disease if airborne bacteria land on reading material and are transmitted to the reader; however, the activity is not a significant health concern as long as the reading environment is sanitary, the reader does not have a compromised immune system, and the reader practices ordinary hygiene.
A University of Arizona microbiologist who researched the topic in 2002 found that bathroom reading at the workplace was not a significant hygiene risk, noting that paper is a relatively unattractive environment for bacteria and that desk areas often have more bacteria than bathrooms because they are cleaned less frequently.
Although time spent on the toilet can increase the incidence of hemorrhoids, a 2009 study found that bathroom readers were not more likely than non-bathroom readers to have hemorrhoids.
Bathroom reading and psychology
Even when people read for extended periods of time during defecation, it is rare for bathroom readers to feel disgusted by the smell of their own feces, or even to consciously notice the smell. Sigmund Freud also noted this phenomenon in Civilization and Its Discontents, though he described lack of awareness of fecal smell in general, not just while reading: "in spite of all man's developmental advances, he scarcely finds the smell of his own excreta repulsive, but only that of other people's."
The psychoanalyst Otto Fenichel believed bathroom reading was an indication of early childhood trauma. He wrote that the activity is "an attempt to preserve the equilibrium of the ego; part of one's bodily substance is being lost and so fresh matter must be absorbed through the eyes." James Strachey, who translated Freud's works into English, similarly noted that the activity of casual reading while defecating was essentially "infantile" behavior.
DiMassimo Brand Advertising once tested political advertising in bathrooms by placing various messages about George W. Bush and Al Gore in New York City public restrooms. The company's study found that 62 percent of people "remembered the exact message" of bathroom ads, compared to 16 percent for billboard advertisements.
See also
Toilet meal
Bathroom sex
Mariko Aoki phenomenon, in which the smell of bookstores induces an urge to defecate
References
Bathrooms
Reading (process)
Toilets | Bathroom reading | [
"Biology"
] | 825 | [
"Excretion",
"Toilets"
] |
58,405,077 | https://en.wikipedia.org/wiki/Late%20Elongated%20Hypocotyl | The Late Elongated Hypocotyl gene (LHY), is an oscillating gene found in plants that functions as part of their circadian clock. LHY encodes components of mutually regulatory negative feedback loops with Circadian Clock Associated 1 (CCA1) in which overexpression of either results in dampening of both of their expression. This negative feedback loop affects the rhythmicity of multiple outputs creating a daytime protein complex. LHY was one of the first genes identified in the plant clock, along with TOC1 and CCA1. LHY and CCA1 have similar patterns of expression, which is capable of being induced by light. Single loss-of-function mutants in both genes result in seemingly identical phenotypes, but LHY cannot fully rescue the rhythm when CCA1 is absent, indicating that they may only be partially functionally redundant. Under constant light conditions, CCA1 and LHY double loss-of-function mutants fail to maintain rhythms in clock-controlled RNAs.
The circadian clock in plants has completely different components to those in the animal, fungus or bacterial clocks. The plant clock does have a conceptual similarity to the animal clock in that it consists of a series of interlocking transcriptional feedback loops. The genes involved in the clock show their peak expression at a fixed time of day. The peak expression of the CCA1 and LHY genes occurs at dawn, and the peak expression of the TOC1 gene occurs roughly at dusk. CCA1/LHY and TOC1 proteins repress the expression of each others genes. The result is that as CCA1/LHY protein levels start to reduce after dawn, it releases the repression on the TOC1 gene, allowing TOC1 expression and TOC1 protein levels to increase. As TOC1 protein levels increase, it further suppresses the expression of the CCA1 and LHY genes. The opposite of this sequence occurs overnight to re-establish the peak expression of CCA1 and LHY genes at dawn.
CCA1 is generally a more significant component of this oscillator. Light induces its transcription, and mRNA levels peak at dawn along with LHY. CCA1 and LHY associate to inhibit transcription of the Evening Complex (EC) proteins: ELF4, ELF3 and LUX, which suppresses their accumulation until dusk when LHY and CCA1 protein levels are at their lowest. Four primary pseudo-response regulator proteins (PRR9, PRR7, PRR5 and TOC1/PRR1) perform the majority of interactions with other proteins within the circadian oscillator, and another (PRR3) that has limited function. These genes are all paralogs of each other, and all repress the transcription of CCA1 and LHY at various times throughout the day.
Plants that have lost function of LHY and CCA1 lose the ability to stably maintain circadian rhythm and other output phenomena. In one study, such plants showed photoperiod- insensitive early flowering under long- day (16 hours of light/ 8 hours of dark) conditions and short day (8 hours of light, 16 hours of dark conditions), and arrhythmicity under constant light conditions. However they retain some circadian function in light/dark cycles, showing that Arabidopsis circadian clock is not completely dependent on CCA1 and LHY activity. Plants with non-functioning LHY and CCA1 show a wavy leaf phenotype in constant light conditions. Mutants also have increased vascular pattern complexity in their leaves, with more areoles, branch points and free ends than wild-type Arabidopsis.
The function of LHY was initially demonstrated by a group in the Steve Kay lab, including Andrew Millar.
References
Attribution: This article contains material originally copied from Circadian clock, Circadian Clock Associated 1, Oscillating gene, and Pseudo-response regulator.
Plant genes
Circadian rhythm | Late Elongated Hypocotyl | [
"Biology"
] | 808 | [
"Behavior",
"Sleep",
"Circadian rhythm"
] |
58,405,262 | https://en.wikipedia.org/wiki/LifeAct%20Dye | LifeAct is a 17 amino acid recombinant peptide that stains filamentous actin (F-actin) structures of eukaryotic living or fixed cells. There are several types and combinations of LifeAct that can be utilized depending on the cell type, protocol, and purpose of the analysis.
Lifeact amino acid sequence
Lifeact 17 amino acid sequence is MGVADLIKKFESISKEE.
Types
LifeAct Plasmid
LifeAct mRNA
LifeAct Adenovirus
LifeAct Lentivirus
LifeAct Protein
Chemistry
LifeAct-TagGFP2 being the most widely used fluorescent variant compared to other LifeAct constructs is composed of the first 17 amino acid from the Saccharomyces cerevisiae Abp140, an actin-binding protein. The Abp140 is highly conserved among Saccharomyces cerevisiae and other closely related organisms. The 17 amino acid fragment of Abp140 was genetically fused to GFP and fluoresces green when it binds the F-actin structures of living and fixed cells, allowing for visualization of cell mechanics under microscopes. Previous experiments involving the analysis of cell mechanics had depended on fluorescently labeled phalloidin and actin GFP fusion proteins obtained from utrophin in Xenopus laevis and ABP120 in Dictyostelium discoideum. However, due to their large protein size, markers such as phalloidin and GFP fusion proteins are limited to cells that can be transfected and tend to compete with their orthologous protein. These localization markers affect cellular mechanical properties and F-actin structures, thus making these markers unreliable. An alternative to these markers is Life Act-TagGFP2, which is a much smaller protein and does not affect cell mechanics. Cells synthesize LifeAct-TagGFP2 in a short period of time at a cost-effective making it suitable as an in vivo marker.
Applications in biomedical research
LifeAct peptides have been used as a universal marker for F-actin visualization in biomedical research. An experiment conducted by Sawant et al. utilized LifeAct GFP to visualize the migration of control border cells in the ovaries of Drosophila flies, in order to determine how cells move in terms of small and large collectives during development and cancer. Lifeact labels F-actin in border cells and adjacent follicle cells allowed for the detailed examination of border cell membranes and protrusions. Studies regarding the degradation of actin cytoskeleton due to aging relied on LifeAct for the analysis of cytoskeletal organization as a function of age. Transgenic lines that expressed the LifeAct in various tissues of C. elegans were primarily used for imaging.
References
Protein imaging | LifeAct Dye | [
"Chemistry",
"Biology"
] | 580 | [
"Biochemistry methods",
"Protein imaging"
] |
58,405,438 | https://en.wikipedia.org/wiki/List%20of%20low-code%20development%20platforms | Below is a list of notable low-code development platforms.
Implementations
AppSheet is a no-code application from Google that offers users the ability to create applications for mobile and web.
Acceleo is an open-source code generator for Eclipse used to generate any textual language (Java, PHP, Python, etc.) from EMF models defined from any many (UML, SysML, etc.).
Actifsource is a plugin for Eclipse that allows graphical modelling and model-based code generation using custom templates.
Appian is an enterprise low-code automation platform for mobile application development. The platform includes a visual interface and pre-built development modules.
Betty Blocks is a software-as-a-service no-code platform.
Caspio is a low-code application development platform for creating online databases and web applications.
DMS Software Reengineering Toolkit is a system for defining arbitrary domain-specific languages and translating them to other languages.
Claris FileMaker is a low-code development platform targeting mobile, cloud and on-premise environments.
GeneXus is a cross-platform, knowledge representation-based development tool mainly oriented to enterprise-class applications for web applications, smart devices, and Microsoft Windows. A developer describes an application in a high-level, mostly declarative language, from which native code is generated for multiple environments.
Jam.py is a free and open-source development platform for database-driven business web applications, based on DRY principle, with emphasis on CRUD.
The Maple computer algebra system offers code generators for Fortran, MATLAB, C, and Java. Wolfram Language (Mathematica), and MuPAD have comparable interfaces.
Mendix is a low-code platform that provides tools for organizations to build web and mobile applications using visual drag-and-drop elements.
Microsoft Power Automate (previously known as Microsoft Flow) is a low-code platform used for creating tailored end-to-end process automation.
OSBP is a software factory provided as open source by the Eclipse Foundation. It combines no-code/low-code elements with classic software development. Coding is largely replaced by a descriptive modeling of the desired software, while allowing developers to integrate their own source code. The applications are intended for professional use in companies.
Oracle APEX is a simple, proprietary low-code environment from Oracle.
OutSystems is a low-code platform for omnichannel enterprise application development.
Salesforce is a low-code platform for enterprise application development, especially CRM and ERP.
Spring Roo is an open source active code generator for Spring Framework based Java applications. It uses AspectJ mixins to provide separation of concerns during round-trip maintenance.
Trackvia is a low-code platform first released in 2007.
UiPath is a low-code/no-code development platform for enterprise automation and robotic process automation (RPA).
Uniface is a provider of model-driven, low code application development software for developers, enterprises and ISV's.
WaveMaker is an enterprise low-code platform mainly oriented towards core application development and delivery users. The applications created are largely open-standards-based and the tool can be used to generate code in the background by drag and drop visual development.
See also
Compiler optimization
Declarative programming
Graphical user interface
Integrated development environment (IDE)
Refactor
Robotic Process Automation (RPA)
Snippet management
User interface markup language
wizard (software)
References
Programming paradigms
Source code generation
Low-code development | List of low-code development platforms | [
"Technology"
] | 722 | [
"Computing-related lists",
"Lists of software"
] |
58,406,541 | https://en.wikipedia.org/wiki/Aspergillus%20costaricaensis | Aspergillus costaricaensis is a species of fungus in the genus Aspergillus. A. costaricaensis belongs to the group of black Aspergilli that are used in industry to create enzymes and other products. A. costaricaensis belongs to the Nigri section. The species was first described in 2004. It has been found in soil in Gaugin Garden on Taboga Island, Costa Rica. It produces large pink to greyish brown sclerotia.
The genome of A. costaricaensis was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 36.95 Mbp.
Growth and morphology
Aspergillus costaricaensis has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
costaricaensis
Fungi described in 2004
Fungus species | Aspergillus costaricaensis | [
"Biology"
] | 229 | [
"Fungi",
"Fungus species"
] |
58,407,235 | https://en.wikipedia.org/wiki/Transposase-2%20RNA%20motif | The Transposase-2 RNA motif is a conserved RNA structure that was discovered by bioinformatics.
These RNAs are usually located nearby to genes that encode transposases, which are the main component of transposons. Many kinds of transposon are found adjacent to inverted repeats, which could be mistaken for simple RNA secondary structures. Therefore, Transposase-2 RNAs could reflect this side effect of transposon replication, and not encode a separate RNA. However, the consistency of the RNA's alignment (e.g., all RNAs have the complete secondary structure, with no truncations) is not typical of transposon-associated repeats. Assuming that Transposase-2 RNAs do function as RNAs, they might function as cis-regulatory elements to regulate the transposase genes, or they might operate in trans as small RNAs that participate in the transposon's biology in some other way.
Transposase-2 motif RNAs are found in two different bacterial phyla: Actinomycetota and Bacillota.
Although their presence in two phyla could suggest that they are highly diverged, and have a very old origin, in view of their association with transposons, it is fairly likely that the widespread distribution of these RNAs is a result of relatively recent horizontal gene transfer.
References
Non-coding RNA | Transposase-2 RNA motif | [
"Chemistry"
] | 295 | [
"Molecular biology stubs",
"Molecular biology"
] |
75,085,196 | https://en.wikipedia.org/wiki/Effective%20accelerationism | Effective accelerationism, often abbreviated as "e/acc", is a 21st-century philosophical movement that advocates for an explicitly pro-technology stance. Its proponents believe that unrestricted technological progress (especially driven by artificial intelligence) is a solution to universal human problems like poverty, war and climate change. They see themselves as a counterweight to more cautious views on technological innovation, often giving their opponents the derogatory labels of "doomers" or "decels" (short for decelerationists).
The movement carries utopian undertones and argues that humans need to develop and build faster to ensure their survival and propagate consciousness throughout the universe. Its founders Guillaume Verdon and the pseudonymous Bayeslord see it as a way to "usher in the next evolution of consciousness, creating unthinkable next-generation lifeforms."
Although effective accelerationism has been described as a fringe movement and as cult-like, it has gained mainstream visibility in 2023. A number of high-profile Silicon Valley figures, including investors Marc Andreessen and Garry Tan explicitly endorsed it by adding "e/acc" to their public social media profiles.
Etymology and central beliefs
Effective accelerationism, a portmanteau of "effective altruism" and "accelerationism", is a fundamentally techno-optimist movement. According to Guillaume Verdon, one of the movement's founders, its aim is for human civilization to "clim[b] the Kardashev gradient", meaning its purpose is for human civilization to rise to next levels on the Kardashev scale by maximizing energy usage.
To achieve this goal, effective accelerationism wants to accelerate technological progress. It is strongly focused on artificial general intelligence (AGI), because it sees AGI as fundamental for climbing the Kardashev scale. The movement therefore advocates for unrestricted development and deployment of artificial intelligence. Regulation of artificial intelligence and government intervention in markets more generally is met with opposition. Many of its proponents have libertarian views and think that AGI will be most aligned if many AGIs compete against each other on the marketplace.
The founders of the movement see it as rooted in Jeremy England's theory on the origin of life, which is focused on entropy and thermodynamics. According to them, the universe aims to increase entropy, and life is a way of increasing it. By spreading life throughout the universe and making life use up ever increasing amounts of energy, the universe's purpose would thus be fulfilled.
History
Intellectual origins
While Nick Land is seen as the intellectual originator of contemporary accelerationism in general, the precise origins of effective accelerationism remain unclear. The earliest known reference to the movement can be traced back to a May 2022 newsletter published by four pseudonymous authors known by their X (formerly Twitter) usernames @BasedBeffJezos, @bayeslord, @zestular and @creatine_cycle.
Effective accelerationism incorporates elements of older Silicon Valley subcultures such as transhumanism and extropianism, which similarly emphasized the value of progress and resisted efforts to restrain the development of technology, as well as the work of the Cybernetic Culture Research Unit.
Disclosure of the identity of BasedBeffJezos
Forbes disclosed in December 2023 that the @BasedBeffJezos persona is maintained by Guillaume Verdon, a Canadian former Google quantum computing engineer and theoretical physicist. The revelation was supported by a voice analysis conducted by the National Center for Media Forensics of the University of Colorado Denver, which further confirmed the match between Jezos and Verdon. The magazine justified its decision to disclose Verdon's identity on the grounds of it being "in the public interest".
On 29 December 2023 Guillaume Verdon was interviewed by Lex Fridman on the Lex Fridman Podcast and introduced as the "founder of [the] e/acc (effective accelerationism) movement".
Second Trump presidency
Following Donald Trump's victory in the 2024 U.S. presidential election, several prominent tech industry figures expressed support for positions aligned with effective accelerationism, particularly regarding deregulation and technological advancement. The potential appointment of Elon Musk to government roles focused on auditing federal programs drew support from venture capitalists who anticipated reduced regulatory oversight of the technology sector.
Notable tech figures publicly connected these developments to the movement's principles. Aaron Levie, CEO of Box, expressed support for "removing unnecessary red tape and over-regulation," while Mark Pincus, early Facebook investor and Zynga founder, explicitly referenced "effective accelerationism" in his post-election commentary. Venture capitalists viewed the incoming administration as an opportunity to ease regulations that had affected technology mergers and acquisitions during the previous years.
Relation to other movements
Traditional accelerationism
Traditional accelerationism, as developed by the British philosopher Nick Land, sees the acceleration of technological change as a way to bring about a fundamental transformation of current culture, society, and the political economy. In his earlier writings he saw the acceleration of capitalism as a way to overcome this economic system itself. In contrast, effective accelerationism does not seek to overcome capitalism or to introduce radical societal change but tries to maximize the probability of a technocapital singularity, triggering an intelligence explosion throughout the universe and maximizing energy usage.
Effective altruism
Effective accelerationism also diverges from the principles of effective altruism, which prioritizes using evidence and reasoning to identify the most effective ways to altruistically improve the world. This divergence comes primarily from one of the causes effective altruists focus on – AI existential risk. Effective altruists argue that AI companies should be cautious and strive to develop safe AI systems, as they fear that any misaligned AGI could eventually lead to human extinction. Proponents of effective accelerationism generally consider that existential risks from AGI are negligible, and that even if they were not, decentralized free markets would much better mitigate this risk than centralized governmental regulation.
d/acc
Introduced by Vitalik Buterin in November 2023, d/acc is pro-technology like e/acc. But it assumes that maximizing profit does not automatically lead to the best outcome. The "d" in d/acc primarily means "defensive", but can also refer to "decentralization" or "differential". d/acc acknowledges existential risks and seeks a more targeted approach to technological development than e/acc, intentionally prioritizing technologies that are expected to make the world better or safer.
Degrowth
Effective accelerationism also stands in stark contrast with the degrowth movement, sometimes described by it as "decelerationism" or "decels". The degrowth movement advocates for reducing economic activity and consumption to address ecological and social issues. Effective accelerationism on the contrary embraces technological progress, energy consumption and the dynamics of capitalism, rather than advocating for a reduction in economic activity.
Reception
The "Techno-Optimist Manifesto", a 2023 essay by Marc Andreessen, has been described by the Financial Times and the German Süddeutsche Zeitung as espousing the views of effective accelerationism.
David Swan of The Sydney Morning Herald has criticized effective accelerationism due to its opposition to government and industry self-regulation. He argues that "innovations like AI needs thoughtful regulations and guardrails [...] to avoid the myriad mistakes Silicon Valley has already made". During the 2023 Reagan National Defense Forum, U.S. Secretary of Commerce Gina Raimondo cautioned against embracing the "move fast and break things" mentality associated with "effective acceleration". She emphasized the need to exercise caution in dealing with AI, stating "that's too dangerous. You can't break things when you are talking about AI". In a similar vein, Ellen Huet argued on Bloomberg News that some of the ideas of the movement were "deeply unsettling", focusing especially on Guillaume Verdon's "post-humanism" and the view that "natural selection could lead AI to replace us [humans] as the dominant species."
See also
Technological utopianism
Transhumanism
References
External links
Computational neuroscience
Concepts in ethics
Cybernetics
Doomsday scenarios
Effective altruism
Ethics of science and technology
Existential risk from artificial general intelligence
Future problems
Human extinction
Philosophy of artificial intelligence
Singularitarianism
Technology hazards
Effective accelerationism | Effective accelerationism | [
"Technology",
"Engineering",
"Biology"
] | 1,710 | [
"Effective altruism",
"Behavior",
"Existential risk from artificial general intelligence",
"Altruism",
"Genetic engineering",
"Transhumanism",
"nan",
"Ethics of science and technology"
] |
75,085,539 | https://en.wikipedia.org/wiki/Dust%20ponds | Dust ponds are a phenomenon where pockets of dust are seen in celestial bodies without a significant atmosphere, like asteroids, comets and some minor planets. These are smooth deposits of dust accumulated in depressions on the surface of the body (like craters), contrasting from the rocky terrain around them. They typically have different color and albedo compared to the surrounding areas. As there are no air around them, their method of formation is still debated. The phenomenon was discovered on 2000 October 28, by the spaceprobe NEAR Shoemaker on Asteroid 433 Eros.
Cause
On airless bodies, electrostatic transport is believed to be the leading cause of dust transport. Infrared rays and ultraviolet rays from the Sun are strong enough to knock electrons off the dust present on surface. These positively charged particles get repelled from the surface kilometers high. On the night side, the dust is negatively charged by electrons from the solar wind. Particles at the night side would achieve greater electrical tension differences than the day side, launching dust particles to even higher altitudes. Laboratory experiments show that dusty surfaces tend to become smooth as a result of dust mobilization. When these levitated dust travels into a shadowed region, they lose their charge and fall to the ground. Over time, dust accumulate on such places. This is believed to be the leading cause of Dust ponds. However, the precise mechanics of electrostatic dust launching remain mysterious. The high obliquity of Eros (88°) results in low latitudes spending more time with the Sun near the horizon than higher latitudes. This results in more dust ponds in the equatorial region. Electrostatically levitated dust is believed to be the cause of a phenomenon named lunar horizon glow, where such particles scatter sunlight during lunar sunset, creating a shining horizon.
Apart from this, seismic shaking, outgassing, and fluidization is also believed to be the cause, although all of these theories contain some flaws. Fluidization of impact ejecta is believed to be the cause of structures named melt pools on moon. This results is two types of dust ponds, that of impact melt (type 1) and that of (Dust accumulation). Type 1 ponds are located near the impact melt of large craters. The dust is uniformly distributed across the crater floor, producing smooth pond surfaces with a constant slope and shallow depth. The dust ponds however, have a less constant slope. Type 2 ponds are rare in moon because more electrostatic tension is needed to overcome the gravitational pull of the moon. In asteroids with low gravity, less electrostatic difference is needed, resulting in more type-2 dust ponds.
The variation in albedo is thought to be due to mineral heterogeneity, or the difference in grain size. The material is distributed in the crater with a slight offset in the geometric center. Particles in the dust ponds are also rich in Silicate materials (olivine and pyroxenes). The slight blue color of the pond deposits is due to a property of mafic materials that makes them visibly bluer at very fine grain sizes (≤50 μm) due to changes in packing. Overall, ponds are formed in planetary bodies with dry brittle regolith or low volatile content.
Examples
433 Eros contains an abundance of large craters more than 200m in diameter. Their number is near to the saturation point of these craters. But craters smaller than that are relatively low. Suggesting that some process of erasure has covered them up. The floors of some craters are covered with smooth and flat areas (less than 10° slope). Such ponds are observed more near the equator and places with low gravity. They are characterized by slightly bluer colour compared to the surrounding terrain. 334 of such ponds are identified, with a diameter of 10m. 255 of these are larger than 30m, and 231 (or 91%) are found within 30° from the equator. Only 24 of them have clearly flat floors with a change in slope at the edges, and only 12 of them have level topography along both east–west and north–south directions. Dust particles here measure about 2 cm in size.
The dust pond features on Eros are thought to be from dry regolith materials, while that of found in the moon are thought to come from ejecta melt. On the surface of asteroid 4 Vesta both type 1 (ejecta) and type 2 (dust ponds) have been found within 0˚–30°N/S, that is in the equatorial region. 10 craters have been identified on Vesta with dust pond formation. These craters have a diameter of ≤11 km and half of them are scattered in the southern region of the Marcia (average ~75.3 ± 32 km distance from rim) and northern part of Cornelia crater. These craters were photographed in detail by the DAWN probe that orbited Vesta.
In the Sagamihara and Muses-Sea regions of asteroid 25143 Itokawa, dust ponds were identified by Japanese probe Hayabusa. Dust particles here are finer than that of 433 Eros with size varying from millimeters to less than a centimeter.
See also
Lunar horizon glow
References
Space science
Planetary geology | Dust ponds | [
"Astronomy"
] | 1,049 | [
"Space science",
"Outer space"
] |
75,085,824 | https://en.wikipedia.org/wiki/Monitor%20of%20Settlement%20and%20Open%20Space%20Development | The Monitor of Settlement and Open Space Development (IÖR-Monitor) is a specialized information system on land use issues in Germany. Since 2010, it has been providing information on the land use structure and its development as well as on landscape quality in high spatial resolution for the terrestrial territory of the Federal Republic of Germany on the basis of indicators. The IOER monitor thus complements the official land use statistics and the environmental-economic accounts with basic information for assessing land development, especially with regard to its sustainability.
The Monitor of Settlement and Open Space Development is a permanent, scientific service provided free of charge by the Leibniz Institute for Ecological Spatial Development (IÖR) in Dresden and part of its research-based policy and social consulting. It therefore also bears the short name IÖR-Monitor. The monitor is successively supplemented with new time periods and indicators in order to be able to assess the state and development of land throughout Germany. For this purpose, IÖR uses the most accurate geotopographic data in Germany (ATKIS Basis-DLM) for all land use indicators, the Digital Land Cover Model (LBM-DE) for the indicators hemeroby and degree of naturalness, official house perimeters (HU-DE) and house coordinates (HK-DE) for the building indicators, as well as geospatial data (protected areas, legally defined floodplains), population grids (from the 2011 census) and statistical data (population, GDP), which are processed in combination.
Functional scope
Almost 80 indicators of the categories settlement, open space, traffic, buildings, landscape quality (e.g. "hemeroby index", "ecotone density"), landscape and nature conservation, ecosystem services, population, risk and relief are now offered. For each indicator, the calculation methodology and meaning is presented in a fact sheet. Recurring, central terms are explained in a glossary.
The following options are available for the output of the indicators:
Maps based on vector data with different spatial extents (municipality to federal level).
Maps based on raster data with high spatial resolution (up to 100 meters raster width)
Tables and development graphs for all indicators (export of table values in CSV file format)
Individually designed maps with storage option and result dispatch by e-mail (modification of color values and number of classes possible)
Area and time comparisons as well as statistical evaluations.
Via an offered Web Map Service (WMS) an integration of the raster maps (100 meter raster width) into own GIS environments is possible.
Meaning
The IÖR-Monitor provides information on the condition and development of land and soil, which is only available to a limited extent and requires protection. It serves as a basis for evaluations and is of particular importance for land budget policy and spatial and sectoral planning at all levels (federal, state, planning regions, counties and municipalities). The IÖR-Monitor can be used, for example, to display and compare variables such as land sealing, population density, transport area per inhabitant and the accessibility of urban green spaces. This information is also of interest to science, business, interested private users and the media and can be accessed on the Internet at any time. In the 3rd Geo Progress Report of the Federal Government, the IOER monitor is cited as an "excellent example of open government". Furthermore, Germany is classified as a European leader in the survey and monitoring of the land use structure based on the analysis results of the monitor. After being selected by a jury, the IÖR monitor was able to present itself to a broad public as a service for responsible future design at the Week of the Environment (2016).
By providing information on settlement and transport land development, the IÖR-Monitor contributes to the national sustainability strategy of 2002, in which the German government set the goal of reducing land consumption by settlement and transport uses in Germany to 30 hectares per day by 2020 (30-hectare target). Accurate and up-to-date land monitoring is needed to evaluate the achievement of this target.
References
Information systems
Nature conservation in Germany
Urban planning in Germany
Settlement geography | Monitor of Settlement and Open Space Development | [
"Technology"
] | 837 | [
"Information systems",
"Information technology"
] |
75,085,853 | https://en.wikipedia.org/wiki/Dirac%20Medal%20%28IOP%29 | The Paul Dirac Medal and Prize is a gold medal awarded annually by the Institute of Physics (Britain's and Ireland's main professional body for physicists) for "outstanding contributions to theoretical (including mathematical and computational) physics". The award, which includes a £1000 prize, was decided upon by the Institute of Physics in 1985, and first granted in 1987.
Recipients
See also
List of physics awards
List of awards named after people
References
Awards of the Institute of Physics
British science and technology awards
Physics awards
Awards established in 1985 | Dirac Medal (IOP) | [
"Technology"
] | 108 | [
"Science and technology awards",
"Physics awards"
] |
75,087,301 | https://en.wikipedia.org/wiki/Pathobiont | A pathobiont is an organism that is native to the host's microbiome that under certain environmental or genetic changes can become pathogenic and induce disease.
Pathobionts differ from opportunistic pathogens in the sense that they are normally native to the microbiome, where opportunistic pathogens are acquired from outside that microbiome.
Etymology
The term was originally coined in 2008 by Sarkis Mazmanian to describe Helicobacter hepaticus and its ability to cause colitis under certain environmental conditions.
The term pathobiont had mixed reception among the microbiology field. The main argument against using the term is that some bacteria labelled as pathobionts also exhibit beneficial effects to hosts under normal conditions. The notion that their pathogenesis is tied to environmental or genetic changes from a perceived normal state would point to a firm understanding of a normal gut microbiome, which can vary drastically. Arguers against the term state all bacteria have metabolism that are environmentally dependent, and even symbionts have been shown to exhibit deleterious clinical effects under certain conditions. The argument has led to the development of a proposed term, pathogenic potential, to describe a microbe's ability to cause disease. Both terms are currently used within the field.
References
Microbiomes
Pathogenic bacteria
Pathogenic microbes | Pathobiont | [
"Environmental_science"
] | 276 | [
"Microbiomes",
"Environmental microbiology"
] |
75,087,415 | https://en.wikipedia.org/wiki/TTFB%20%28chemical%29 | TTFB (4,5,6,7-Tetrachloro-2-trifluoromethylbenzimidazole) is a halogenated benzimidazole derivative that acts as an uncoupling agent.
See also
2,4-Dinitrophenol
Perfluorotriethylcarbinol
SF-6847
References
Benzimidazoles
Chloroarenes
Trifluoromethyl compounds
Uncouplers | TTFB (chemical) | [
"Chemistry",
"Biology"
] | 102 | [
"Cellular respiration",
"Biotechnology stubs",
"Biochemistry stubs",
"Biochemistry",
"Uncouplers"
] |
75,088,035 | https://en.wikipedia.org/wiki/E-Lab | E-Lab was a research and design consultancy established in Chicago, Illinois in 1994 by Rick Robinson, John Cain and Mary Beth McCarthy. The firm and its founders were part of a movement in the late 1980s when organizations such as Xerox/PARC (Palo Alto Research Center], IBM, Institute for Research on Learning and Jay Doblin & Associates embraced social science approaches in their product design and development efforts. E-Lab became known for pioneering a multidisciplinary, human-centric methodology strongly guided by anthropology and ethnography that was equally balanced between research and design. Its approach challenged conventional market research by prioritizing real-world user experiences and behaviors uncovered through fieldwork, helping to establish new practices termed "human-centered design," "design ethnography" and "design anthropology." In 1996, the business magazine Fast Company characterized E-Lab's approach as "simple but subversive" and "at the forefront of a growing movement to rethink how companies understand customers and create products that meet their needs."
In 1999, E-Lab was acquired by the technology consulting firm Sapient Corp. and became that company's "experience modeling" discipline, renamed "Xmod." In the 2000s, as former E-Lab/Xmod researchers and designers joined and formed other firms and organizations, its influence on the practice of anthropology and other social-science research in business spread. In 2009, anthropology researcher Melissa Cefkin wrote, "Robinson, Cain and their colleagues at the Doblin Group, E-Lab and Sapient contributed considerably to the development of current norms and forms of ethnographically oriented strategy and design consulting."
History
E-Lab's founders met as co-workers at Doblin Group (initially Jay Doblin & Associates), a Chicago-based design consultancy. John Cain joined Doblin as a design strategist in 1987, and later became its design practice lead, after studying engineering and earning a BS in industrial design at the IIT Institute of Design. Rick Robinson completed a Ph.D. in human development at University of Chicago, studying with Mihaly Csikszentmihalyi; he was hired at Doblin in 1989 and became head of research. Mary Beth McCarthy joined the firm as a comptroller in 1991.
Their work at Doblin was cross-disciplinary, integrating ethnographic research, design and strategy, as did contemporary firms such as Fitch and IDEO. A breakthrough collaboration was the "Workplace Project" (1989) with Steelcase and Xerox/PARC, in which they worked with researchers including anthropologist Lucy Suchman, human-computer scientist Austin Henderson and linguists Charles and Marjorie H. Goodwin. Anthropology researchers Patricia L. Sunderland and Rita M Denny credited that project with catalyzing the growth and visibility of applied anthropology in design, consumer research and business discourse in the U.S. Anthropologist Marietta L. Baba wrote that the interdisciplinary project "would revolutionize the design industry" by conceptualizing the idea notion that new product and service concepts should emerge from "a contextually-rich understanding of the client’s natural world, developed through ethnographic field research at client sites," a concept that E-Lab would later take to the market.
In 1994, Cain, McCarthy and Robinson left Doblin to start a new type of consultancy more purely devoted to the integration of research and design and to ethnographic methodologies rather than strategy. They named it "E-Lab"—the "e" representing everyday experience and ethnography and "lab" positioning the firm as a product research laboratory for understanding and innovation. E-Lab's approach to disciplinary boundaries and hierarchy was egalitarian and fluid, equally balancing design professionals and young social-science researchers across many fields recruited through university graduate programs.
After securing initial projects from former Doblin clients Hallmark, McDonald's, Steelcase and Thomson Consumer Electronics (RCA), E-Lab attracted other projects from well-known technology and consumer product firms, automobile manufacturers, fast food restaurants and convenience store chains over five years, increasing its staff to nearly fifty employees. It also gained wider recognition through features in trade publications and the business magazines Fast Company, Business Week and Financial Times, speaking and writing engagements, and commentary in national features on the design of corporate workspaces, headquarters and identity.
After E-Lab was acquired by Sapient (then an internet systems company moving into design, communications and branding) in fall of 1999, it evolved into that firm's "experience modeling" discipline, "Xmod", and expanded into online brands. The acquisition more than doubled E-Lab's staff to fill offices in London, New York, San Francisco, Atlanta, and Sydney, with Robinson heading the new discipline as one of the first "chief experience officers."
In the 2000s, E-Lab's methodologies and philosophy continued to be an integral part of Sapient and other organizations through the spread of its multidisciplinary researchers.<ref name="BW12">Business Wire'''. "SapientNitro Deepens Capabilities in Data and Analytics as Iota Partners Joins Company." September 18, 2012. Retrieved September 19, 2023.</ref> After leaving Sapient, Cain and Robinson again collaborated in 2010, on the founding of Iota Partners, a firm focused on instrumentation-driven consumer research, data and analytics; it too was acquired by Sapient (then SapientNitro), in 2012.
Philosophy, methodologies and tools
According to anthropologist Christina Wasson, E-Lab's principle of an equal partnership between research and design represented a then-novel shift from the traditional representation of design as "as an autonomous, inward-looking relationship between designer and product" that positioned research as secondary. The firm was strongly guided by a commitment to ethnography as a creative means of discovering cultural patterns and models and to a collaborative process throughout project development and execution that gave ethnographers a significant voice. Its multidisciplinary methodology was framed by anthropology but also drew upon sociology, human development, literary narrative, cultural theory and art history.
E-Lab's process was inductive; it involved gathering data on naturally occurring consumer behaviors through field observation (in person or by camera) and various self-reporting tools, analyzing it for patterns, and only then developing hypotheses. Going beyond basic qualitative research, the firm employed an analytic process that organized data through frameworks—explanatory concepts that identify key components of an experience and draw out underlying beliefs, attitudes and structural relationships on individual, social and cultural levels.Robinson, Rick E. "Making Sense of Making Sense: Frameworks and Organizational Perception," Design Management Journal, Winter 1994. Frameworks were developed into "experience models": simple but memorable narratives that can pinpoint gaps in an event and facilitate the generation of opportunities for design solutions and strategic action. These concepts flew in the face of both conventional product development—which often took a producer-centric direction fixated on features at the expense of user issues—and quantitative market research based on focus groups and attitude surveys, which measured what people say but missed unarticulated, unconscious meanings. Fast Company wrote that E-Lab's approach suggested "the secret to breakthrough innovation is understanding how people behave: what they do and how they live."
Many of E-Lab's methods became commonplace in what came to be known as design ethnography. Its tools, among others, included: field observation, "shadowing" (field observation with questions); and "intercept interviews"; "guerrilla video" of consumer behavior in stores and in public; proprietary software and telestrators used to index and diagram video images frame-by-frame; beepers and disposable cameras subjects used to document and self-report based on the longitudinal experience sampling method (ESM) developed by Mihaly Csikszentmihalyi, Reed Larson and Suzanne Prescott;.Csikszentmihalyi, Mihaly, Reed Larson and Suzanne Prescott. "The ecology of adolescent activity and experience," Journal of Youth and Adolescence, September 1977, p. 281–94. Retrieved October 12, 2023. and dedicated project rooms with floor-to-ceiling tackable surfaces and whiteboards to track ongoing project narratives.
Clients and projects
E-Lab's clients included technology product firms such as Apple, Claris, Netscape, Nokia, Texas Instruments and Thomson, consumer product companies like BP, Frito-Lay/PepsiCo, Hallmark, JanSport, Schick, Steelcase and Warner-Lambert, automakers (BMW, Ford, General Motors), and fast food (McDonald's) and convenience store chains.
Its work ranged widely, including among other projects, ethnographic fieldwork on customer behavior and store layout (for card stores, gas stations and snack food display) and workspace design; the shadowing of law enforcement officers to investigate mobility, connectivity and communications needs for new communication devices; and studies of teen mood swings and interactions with music, home audio equipment set-ups and usage, how people get sick and recover, the backpacks of middle-schoolers, personal and familial associations connected to cookware, and family message and schedule locations, among other subjects.
Legacy
E-Lab's influence on design ethnography and product development practices extend through its early inception, operation within Sapient, diaspora across numerous organizations, and the written record of academic and trade papers and presentations by its partners and employees.Robinson, Rick E. "Let’s Have a Conversation," in Proceedings of Ethnographic Praxis in Industry Conference, American Anthropological Association, Ken Anderson and Tracey Lovejoy (eds.), 2005. Cain and Robinson published articles in journals such as Design Management Review, American Center for Design Journal, and Innovation'', among others; Robinson presented at the Doors of Perception 6 conference (2000) and gave the keynote presentation at the inaugural EPIC (Ethnographic Praxis in Industry Conference) in 2005.
Former employees that have taken significant roles in other organizations and produced research in the field include: Luis Arnal (Insitum, Fjord), Maria Bezaitis (Intel), Jeanette Blomberg (IBM), Mark Burrell (IBM), Melissa Cefkin (Nissan), Martha Cotton (Fjord), Jodi Forlizzi (Carnegie Mellon University), Kelly L. Franznick (Blink), Rachel Jones (Microsoft, Hitachi, Instrata), Johanna Schoss (Biogen), Dori Tunstall (Design for Democracy), and Christina Wasson, among others.
References
External links
Rick Robinson author page, EPIC
EPIC (Ethnographic Praxis in Industry Conference)
Design
Design companies of the United States
Design companies established in 1994
Industrial design firms
Research and development in the United States
Companies based in Chicago
Defunct companies based in Chicago | E-Lab | [
"Engineering"
] | 2,260 | [
"Design"
] |
75,089,208 | https://en.wikipedia.org/wiki/Agaricus%20alligator | Agaricus alligator is a species of mushroom-forming fungus in the family Agaricaceae. It is endemic to the US. It was first described in 1945.
See also
References
alligator
Taxa named by William Alphonso Murrill
Fungi described in 1945
Fungus species | Agaricus alligator | [
"Biology"
] | 56 | [
"Fungi",
"Fungus species"
] |
75,090,345 | https://en.wikipedia.org/wiki/279%20%28number%29 | 279 (two hundred [and] seventy-nine) is the natural number following 278 and preceding 280.
In mathematics
279 is an odd composite number with two prime factors.
Waring’s Conjecture is g(n)=2n+⌊(3/2)n⌋-2. When 8 is plugged in for n, the result is 279. That means that any positive integer can be formed with at most 279 numbers to the 8th power.
279 is the smallest number whose product of digits is 7 times the sum of its digits.
279 can be written as the sum of 4 nonzero perfect squares.
References
Integers | 279 (number) | [
"Mathematics"
] | 129 | [
"Mathematical objects",
"Elementary mathematics",
"Arithmetic",
"Integers",
"Numbers"
] |
75,090,456 | https://en.wikipedia.org/wiki/266%20%28number%29 | 266 (two hundred [and] sixty-six) is the natural number following 265 and preceding 267.
In mathematics
266 is an even composite number with three prime factors.
266 is a repdigit in base 11. In base 11, 266 is 222.
266 is a sphenic number being the product of 3 prime numbers.
266 is a nontotient number which is an even number not in Euler’s totient function.
266 is an inconsummate number.
References
Integers | 266 (number) | [
"Mathematics"
] | 104 | [
"Elementary mathematics",
"Integers",
"Mathematical objects",
"Numbers"
] |
75,090,687 | https://en.wikipedia.org/wiki/TOI-270 | TOI-270, also known as L 231-32, is a red dwarf star away in the constellation Pictor. It has about 39% the mass and 38% the radius of the Sun, and a temperature of about . TOI-270 hosts a system of three known exoplanets.
Planetary system
The three planets of TOI-270 were discovered in 2019 by the transit method with TESS. Their masses have since been measured by both Doppler spectroscopy and transit-timing variations. The innermost planet, TOI-270 b, is a rocky super-Earth, while the two outer planets are mini-Neptunes. TOI-270 b & c orbit near a 5:3 resonance, while TOI-270 c & d orbit near a 2:1 resonance.
Observations of the outermost planet, TOI-270 d, by the Hubble Space Telescope suggest a hydrogen-rich atmosphere with signs of water vapor. TOI-270 c & d are good targets for atmospheric detection with the James Webb Space Telescope.
The James Webb Space Telescope detected methane (CH4), carbon dioxide (CO2) and water vapor in the atmosphere of TOI-270 d. The atmosphere of this planet was also found to be metal-rich, with a mean molecular weight of and an atmospheric metal mass fraction (percentage of the mass of metals in the atmosphere) of . Possible signatures of sulfur dioxide (SO2) and carbon disulfide (CS2) were also found.
References
Pictor
M-type main-sequence stars
Planetary systems with three confirmed planets
J04333970-5157222
0270
259377017
Extraterrestrial water | TOI-270 | [
"Astronomy"
] | 344 | [
"Pictor",
"Constellations"
] |
75,093,073 | https://en.wikipedia.org/wiki/Azomethane | Azomethane is an organic compound with the chemical formula CH3-N=N-CH3. It exhibits cis-trans isomerism. It can be produced by the reaction of 1,2-dimethylhydrazine dihydrochloride with copper(II) chloride in sodium acetate solution. The reaction produces the azomethane complex of copper(I) chloride, which can produce free azomethane by thermal decomposition. It is the source of methyl radical in laboratory.
CH3-N=N-CH3 → 2 CH3· + N2
References
Further reading
Azo compounds
Organic compounds with 2 carbon atoms
Methyl compounds | Azomethane | [
"Chemistry"
] | 138 | [
"Organic compounds",
"Organic compounds with 2 carbon atoms"
] |
75,094,158 | https://en.wikipedia.org/wiki/International%20Fossil%20Plant%20Names%20Index | The International Fossil Plant Names Index (acronym IFPNI) is an online database of paleobotany. The site was launched in May 2014 to list the scientific names of fossil plants, algae, fungi, allied prokaryotic forms (formerly treated as algae and Cyanophyceae in particular), algal-related protists and microfossils published using binomial nomenclature.
References
External links
IFPNI
Fossils
Paleobotany
Organizations established in 2014
Biological databases
Online taxonomy databases | International Fossil Plant Names Index | [
"Biology"
] | 103 | [
"Bioinformatics",
"Biological databases"
] |
75,097,457 | https://en.wikipedia.org/wiki/SPT-140 | SPT-140 is a solar-powered Hall-effect ion thruster, part of the SPT-family of thrusters. SPT stands for Stationary Plasma Thruster. Like other members of the SPT series, it creates a stream of electrically charged xenon ions accelerated by an electric field and confined by a magnetic field.
The thruster is manufactured by the Russian OKB Fakel, who collaborated during development with NASA's Glenn Research Center, Space Systems Loral, and Pratt & Whitney beginning in the late 1980s. It was first tested at the Plasmadynamics and Electric Propulsion Laboratory in 1997. In 2002, it was tested as a 3.5 kW unit by the United States Air Force as part of its Integrated High Payoff Rocket Propulsion Technology program. In 2023, the thruster was launched aboard NASA's Psyche spacecraft.
Specifications
See also
PPS-1350
SPT-100
References
Ion engines
Spacecraft propulsion
Spacecraft components | SPT-140 | [
"Physics",
"Chemistry"
] | 194 | [
"Ions",
"Ion engines",
"Matter"
] |
78,055,482 | https://en.wikipedia.org/wiki/Intent-based%20network | Intent-Based Networking (IBN) is an approach to network management that shifts the focus from manually configuring individual devices to specifying desired outcomes or business objectives, referred to as "intents".
Description
Rather than relying on low-level commands to configure the network, administrators define these high-level intents, and the network dynamically adjusts itself to meet these requirements. IBN simplifies the management of complex networks by ensuring that the network infrastructure aligns with the desired operational goals. For example, an implementer can explicitly state a network purpose with a policy such as "Allow hosts A and B to communicate with X bandwidth capacity" without the need to understand the detailed mechanisms of the underlying devices (e.g. switches), topology or routing configurations.
Architecture
Advances in Natural Language Understanding (NLU) systems, along with neural network-based algorithms like BERT, RoBERTa, GLUE, and ERNIE, have enabled the conversion of user queries into structured representations that can be processed by automated services. This capability is crucial for managing the increasing complexity of network services. Intent-Based Networking (IBN) leverages these advancements to simplify network management by abstracting network services, reducing operational complexity, and lowering costs.
A proposed three-layered architecture integrates intent-based automation into network management systems. In the business layer, intents are based on Key Performance Indicators (KPIs) and Service Level Agreements (SLAs), reflecting business objectives. The intent layer evaluates and re-plans actions dynamically, where a Knowledge module abstracts and reasons about intents, while an Agent interfaces with network objects to execute actions. The data layer observes network objects, updates topology information, and interacts with the Knowledge and Agent modules to ensure accurate and timely responses to network changes. At the bottom, the network layer contains the physical infrastructure, transforming network data into a usable format for the intent layer to act upon.
References
Network management
Computer networks | Intent-based network | [
"Engineering"
] | 397 | [
"Computer networks engineering",
"Network management"
] |
78,055,692 | https://en.wikipedia.org/wiki/Beagle%20Club%20radiation%20experiments | The "Beagle Club" radiation experiments were a series of studies sponsored by the United States Atomic Energy Commission, which took place over four decades starting in the 1950s. They were conducted across six American states at research facilities including Argonne National Laboratory in Chicago; Colorado State University in Fort Collins; Pacific Northwest National Laboratory in Hanford; University of California at Davis; University of Utah in Salt Lake City; and the Inhalation Toxicology Research Institute in Albuquerque.
Studies on the effect of radiation on rats and mice started during and immediately following World War II. Although data from these early studies contributed to setting radiation exposure limits for humans, the small size and short life span of rodents made it difficult to confidently extrapolate what low-level exposure to radiation over longer periods would mean for humans. Experimentation on dogs began at the University of Chicago, University of California at Berkeley, and the University of Rochester. These studies focused on topics such as radionuclide distribution and acute radiation effects, and involved relatively few dogs for short periods of time.
The first two major life-span experiments involving beagles began at the University of California, Davis, and at the University of Utah.
University of California, Davis
Two projects were conducted at the Radiobiology Laboratory at University of California, Davis. The first, Project Four, started in 1951 with the objective of studying the long-term effects of sub-lethal and mid-lethal x-irradiation exposure. The second, Project Six, started in 1957 to investigate the effects of ingesting low levels of radionuclides.
The facility, which became known as the Laboratory for Energy-Related Health Research (LEHR), occupied 15 acres of land. Both projects had the capacity to hold up to five hundred dogs in two-dog pens. By the time the center closed in 1986, the 1,063 female beagles had been exposed to radiation, while many more dogs passed through the facility for breeding and as control subjects.
In the 1990s, the remains of 800 irradiated dogs, their toxic feces, and contaminated gravel were dug up, put in metal drums, and sent to a nuclear disposal site in Washington state. In 2018, UC Davis agreed in a settlement with the United States Environmental Protection Agency to spend $14 million to clean up the landfill adjacent to the former laboratory complex.
References
Animal testing
Biology experiments | Beagle Club radiation experiments | [
"Chemistry"
] | 479 | [
"Animal testing"
] |
78,055,989 | https://en.wikipedia.org/wiki/IRAS%2007598%2B6508 | IRAS 07598+6508 known as IRAS F07599+6508, is a quasar located in the constellation of Camelopardalis. It is located 2.37 billion light years from Earth and is classified as both an ultraluminous infrared galaxy and a Seyfert galaxy.
Characteristics
IRAS 07598+6508 is categorized an advanced galaxy merger. It shows several tidal features according to ground-based optical images. A patchy emission is found having a low-surface brightness of around 22 R magnitude arcsec−2 ,based on Hubble Space Telescope (HST) imaging on the host galaxy. This emission is suggestive of tidal debris created by a recent galaxy-to-galaxy interaction. A deep R-band image reveals the presence of an extended tidal tail from north to east direction. It has a dynamical age of ~ 160 Myr and is curving towards south of the nucleus by ~ 50 kiloparsecs (kpc). Since one tidal tail is clearly seen, the merger was probably caused from the interaction of a spiral and elliptical galaxy.
In addition, IRAS 07598+6508 has several star clusters located both west and south, based on a HST optical image. The galaxy is infrared bright with a source having an estimated luminosity of L2-10keV = 1.12 x 1042 erg s−1.
IRAS 07598+6508 is a low-redshift broad absorption line quasar according to Sebastian Lipari and by ROSAT. It shows abnormally large blueshifts by 3000 km s−1 to a Balmer line as well as sodium (Na I) λ5892 at emission peaks. When looking at both Hα and Hβ intensity ratios, a broad emission line in IRAS 07598+6508 is found reddening by E(B-V) ~ 0.45 with a reddening of a spectral energy distribution of E(B-V) ~ 0.12.
IRAS 07598+6508 is also known to be a strong ferrous (Fe II) emitter although X-ray quiet with a value of αox = 2.45. It has a spectrum being influenced by its tapered broad line region with a full width at half maximum measurement of 1780 km s−1. Besides iron, IRAS 07598+6508 emits spectral lines of titanium (Ti II) and chromium (Cr II). Given its strong Fe II emission, the emission likely derived from a superbubble or was caused by ejected material from a type II supernovae.
Optical HST imaging found two emission clumps, located ~ 7" southeast and south from IRAS 07598+6508. This presence of clumps indicates the emission originates from OB associations and is the key to signs of recent star formation in the galaxy. A NICMOS image of IRAS 07598+6508, finds electromagnetic radiation is controlled by a source of light from the nucleus although low-level emission is also visible right up to ~ 2" radius.
References
External links
IRAS 07598+6508 on SIMBAD
Quasars
Camelopardalis
Galaxy mergers
Seyfert galaxies
097524
F07599+6508
Luminous infrared galaxies | IRAS 07598+6508 | [
"Astronomy"
] | 688 | [
"Camelopardalis",
"Constellations"
] |
78,056,526 | https://en.wikipedia.org/wiki/Subir%20Sarkar | Subir Sarkar (12 September 1953, Ichapur, India) is an Indian astroparticle physicist and cosmologist, known for his research demonstrating constraints on the dark sector.
Education and career
After completing secondary school in 1969, Sarkar studied at IIT Kharagpur, where he graduated with a B.Sc. in 1972 and an M.Sc. in 1974. He then became a graduate student at the Mumbai campus of the Tata Institute of Fundamental Research (TIFR), where he graduated in 1982 with a Ph.D. in physics. From 1979 to 1984 he was a research associate in TIFR's Cosmic Rays Group. In 1983 he was a visiting fellow at the International School for Advanced Studies (Scuola Internazionale Superiore di Studi Avanzati; SISSA) in Trieste. Sarkar was for the academic year 1984–1985 a research associate in CERN's Theory Division and for the academic year 1985–1986 a visiting fellow at the University of Oxford's Department of Astrophysics. For the academic year 1987–1988 he was a research associate in the HEP Theory Group of Rutherford Appleton Laboratory (RAL) in Chilton, Oxfordshire. From 1988 to 1989 he worked in Bhopal for an Indian NGO (Eklavya), specialising in science education and popularisation. In 1990 Sarkar became a staff member of the University of Oxford's Rudolf Peierls Centre for Theoretical Physics. At Wolfson College, Oxford he was a visiting scholar from 1991 to 1993 and a research fellow from 1993 to 1997. At the University of Oxford, he was a departmental lecturer from 1997 to 1998, a tutor in physics at Pembroke College, Oxford from 1997 to 1998. He was promoted to reader in 2000 and professor in 2006, retiring as professor emeritus in 2021. Sarkar headed the University of Oxford's Particle Theory Group from 2011 to 2019. He has also been an adjunct faculty member at TIFR.
Sarkar's research deals with relations between fundamental physics and aspects of astrophysics and cosmology. His research has a wide range, including dark matter, primordial nucleosynthesis, cosmological phase transitions, cosmological inflation, large-scale structure of the universe, and problems with the ΛCDM model. He collaborated with colleagues at the Pierre Auger Observatory, the Big European Bubble Chamber (BEBC), the IceCube Neutrino Observatory, and the Cherenkov Telescope Array in investigations of very high energy cosmic rays and neutrinos. He became a member of the Dark Energy Science Collaboration of the Vera C. Rubin Observatory. He was a founder member of the India Oxford Initiative, which began funding projects in 2019.
The astrophysicist Subir Sarkar should not be confused with the geologist Subir Sarkar, a professor in the Department of Geological Sciences of Jadavpur University.
Awards and honours
In 2017 Sarkar was awarded the Homi Bhabha Medal and Prize. In 2021 he shared in the Bruno Rossi Prize awarded to Francis Halzen and the IceCube collaboration. From the 11th to the 13th of September 2023, Sarkar's collaborators and former students held a celebration in honour of his career achievements and his 70th birthday.
Selected publications
References
1953 births
Living people
IIT Kharagpur alumni
Tata Institute of Fundamental Research alumni
Academics of the University of Oxford
Indian expatriates in England
20th-century Indian physicists
21st-century Indian physicists
Cosmic ray physicists
Particle physicists
Recipients of the Homi Bhabha Medal and Prize | Subir Sarkar | [
"Physics"
] | 726 | [
"Particle physicists",
"Particle physics"
] |
78,056,837 | https://en.wikipedia.org/wiki/Erdogan%E2%80%93Chatwin%20equation | In fluid dynamics, Erdogan–Chatwin equation refers to a nonlinear diffusion equation for the scalar field, that accounts for shear-induced dispersion due to horizontal buoyancy forces. The equation was named after M. Emin Erdogan and Phillip C. Chatwin, who derived the equaiton in 1967. The equation for the scalar field reads
where is a positive constant. For , the equation reduces to the linear heat equation, and for , the equation reduces to .
References
Equations of fluid dynamics
Fluid dynamics
Partial differential equations | Erdogan–Chatwin equation | [
"Physics",
"Chemistry",
"Engineering"
] | 114 | [
"Equations of fluid dynamics",
"Equations of physics",
"Chemical engineering",
"Piping",
"Fluid dynamics"
] |
78,057,369 | https://en.wikipedia.org/wiki/Boles%C5%82aw%20Prus%20Monument | Bolesław Prus Monument () is a bronze statue in Warsaw, Poland, located in the Downtown district on Twardowski Square, near the intersection of Krakowskie Przedmieście and Karowa Streets. It is dedicated to Bolesław Prus, a 19th- and 20th-century novelist, and a leading figure in the history of Polish literature and philosophy. The monument was designed by Anna Kamieńska-Łapińska and unveiled on 15 January 1977.
History
The monument is dedicated to Bolesław Prus, a 19th- and 20th-century novelist, and a leading figure in the history of Polish literature and philosophy. It was first proposed in 1916 in the magazine Tygodnik Illustrowany. The idea was revisited in the early 1960s, in the radio drama The Matysiaks. Money for its construction was donated by Warsaw artisans.
In 1962, four teams of artists were awarded in the contest for the monument's design. However, none of the designs was used. Anna Kamieńska-Łapińska was commissioned to create a new project instead. The monument was unveiled on 15 January 1977.
Charactristics
The monument is located on Twardowski Square, near the intersection of Krakowskie Przedmieście and Karowa Streets. Before the Second World War, at this site stood a building that housed the presses of Kurier Warszawski, a newspaper for which Bolesław Prus wrote.
The monument is a bronze statue 3.6 meters tall, standing on a low granite pedestal. The monument depicts Bolesław Prus as an elderly man in a pensive pose, holding a cane behind his back.
References
Monuments and memorials in Warsaw
1977 establishments in Poland
Buildings and structures completed in 1977
1977 sculptures
Outdoor sculptures in Warsaw
Statues of men in Poland
Statues of writers
Bronze sculptures in Poland
Granite sculptures in Poland
Śródmieście Północne
Colossal statues | Bolesław Prus Monument | [
"Physics",
"Mathematics"
] | 392 | [
"Quantity",
"Colossal statues",
"Physical quantities",
"Size"
] |
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