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Kopp-Etchells effect This may cause difficulty with landing safely, and produce spatial disorientation. With repeated exposure, the Kopp–Etchells effect could damage night vision gear. | https://en.wikipedia.org/wiki?curid=24012524 |
Akrochordite is an exceptionally rare hydrated hydrous arsenate mineral of the formula (Mn,Mg)(AsO)(OH)4HO and represents a small group of rare in the nature manganese (Mn) arsenates and, similarly to most other Mn-bearing arsenates, possess pinkish colour. It is typically associated with metamorphic Mn deposits. | https://en.wikipedia.org/wiki?curid=24020274 |
Andyrobertsite is a rare, complex arsenate mineral with a blue color. It is found in the Tsumeb mine in Namibia and named after Andrew C. Roberts (b. 1950), mineralogist with the Geological Survey of Canada. A Ca-rich analogue (with Ca instead of Cd) is called calcioandyrobertsite and has a more greenish tint. | https://en.wikipedia.org/wiki?curid=24020907 |
Petr Wolfgang Wygodzinsky (5 October 1916, in Bonn – 27 January 1987, in Middletown, New York) was a German entomologist who worked in Argentina, Brazil, and the United States. (Alternate spellings of his name include Peter Wygodzinsky and Pedro Wygodzinsky.) He is especially known for his work on the hemipteran family Reduviidae, but also studied several other groups of insects in detail, namely Diplura, Archaeognatha, Zygentoma and Diptera. He worked at the American Museum of Natural History as an assistant curator (later curator) from 1962 until the end of his career. He published in his native language German as well as in English, Spanish and Portuguese. | https://en.wikipedia.org/wiki?curid=24029784 |
Parallactic angle In spherical astronomy, the parallactic angle is the angle between the great circle through a celestial object and the zenith, and the hour circle of the object. It is usually denoted "q". In the triangle zenith—object—celestial pole, the parallactic angle will be the position angle of the zenith at the celestial object. Despite its name, this angle is unrelated with parallax. The parallactic angle is zero or 180ˆwhen the object crosses the meridian. For ground-based observatories, the Earth atmosphere acts like a prism which disperses light of different wavelengths such that a star generates a rainbow along the direction that points to the zenith. So given an astronomical picture with a coordinate system with a known direction to the North Celestial Pole, the parallactic angle represents the direction of that prismatic effect relative to that reference direction. Depending on the type of mount of the telescope, this angle may also affect the orientation of the celestial object's disk as seen in a telescope. With an equatorial mount, the cardinal points of the celestial object's disk are aligned with the vertical and horizontal direction of the view in the telescope. With an altazimuth mount, those directions are rotated by the amount of the parallactic angle | https://en.wikipedia.org/wiki?curid=24041279 |
Parallactic angle The cardinal points referred to here are the points on the limb located such that a line from the center of the disk through them will point to one of the celestial poles or 90° away from them; these are not the cardinal points defined by the object's axis of rotation. The orientation of the disk of the Moon, as related to the horizon, changes throughout its diurnal motion and the parallactic angle changes equivalently. This is also the case with other celestial objects. In an ephemeris, the position angle of the midpoint of the bright limb of the Moon or planets, and the position angles of their North poles may be tabulated. If this angle is measured from the North point on the limb, it can be converted to an angle measured from the zenith point (the vertex) as seen by an observer by subtracting the parallactic angle. The position angle of the bright limb is directly related to that of the subsolar point. The vector algebra to derive the standard formula is equivalent to the calculation of the long derivation for the compass course. The sign of the angle is basically kept, north over east in both cases, but as astronomers look at stars from the inside of the celestial sphere, the definition uses the convention that the is the angle in an image that turns the direction to the NCP counterclockwise into the direction of the zenith | https://en.wikipedia.org/wiki?curid=24041279 |
Parallactic angle In the equatorial system of right ascension and declination the star is at In the same coordinate system the zenith is found by inserting , into the transformation formulas where is the observer's geographic latitude, the star's altitude, The normalized cross product is the rotation axis that turns the star into the direction of the zenith: Finally is the third axis of the tilted coordinate system and the direction into which the star is moved on the great circle towards the zenith. The plane tangential to the celestial sphere at the star is spanned by the unit vectors to the north, and to the east These are orthogonal: The parallactic angle is the angle of the initial section of the great circle at s, east of north, The values of and of are positive, so using atan2 functions one may divide both expressions through these without losing signs; eventually yields the angle in the full range . The advantage of this expression is that it does not depend on the various offset conventions of ; the uncontroversial offset of the hour angle takes care of this. For a sidereal target, by definition a target where and are not time-dependent, the angle changes with a period of a sidereal day . Let dots denote time derivatives; then the hour angle changes as and the time derivative of the expression is | https://en.wikipedia.org/wiki?curid=24041279 |
Hour circle In astronomy, the hour circle, which together with declination and distance (from the planet's centre of mass) determines the location of any celestial object, is the great circle through the object and the two celestial poles. As such, it is a higher concept than the meridian as defined in astronomy, which takes account of the terrain and depth to the centre of Earth at a ground observer's location. The hour circles, specifically, are perfect circles perpendicular (at right angles) to the celestial equator. By contrast, the declination of an object viewed on the celestial sphere is the angle of that object to/from the celestial equator (thus ranging from +90° to −90°). The location of stars, planets, and other similarly distant objects is usually expressed in the following parameters, one for each of the three spatial dimensions: their declination, right ascension (epoch-fixed hour angle), and distance. These are as located at the vernal equinox for the epoch (e.g. J2000) stated. A meridian on the celestial sphere matches an hour circle at any time. The hour circle is a subtype whereby it is expressed in hours as opposed to degrees, radians, or other units of angle. The hour circles make for easy prediction of the angle (and time due to Earth's fairly regular rotation, approximately equal to the time) between the observation of two objects at the same, or similar declination | https://en.wikipedia.org/wiki?curid=24041303 |
Hour circle The hour circles (meridians) are measured in hours (or hours, minutes, and seconds); one rotation (360°) is equivalent to 24 hours; 1 hour is equivalent to 15°. An astronomical meridian follows the same concept and, almost precisely, the orientation of a meridian (also known as longitude) on a globe. | https://en.wikipedia.org/wiki?curid=24041303 |
Handbook of Porphyrin Science Published by World Scientific, the Handbook of Porphyrin Science: With Applications to Chemistry, Physics, Materials Science, Engineering, Biology and Medicine is a multi-volume reference set edited by scientists Karl Kadish, Kevin Smith and Roger Guilard. The first ten volumes were published in 2010 and the next ten are expected to be published in 2011. Topics covered include: The current work stems from World Scientific's Journal of Porphyrins and Phthalocyanines (JPP) and from the research interests of the three editors and hundreds of authors who have presented the results of their research in this society-run journal since its founding in 1997. | https://en.wikipedia.org/wiki?curid=24041315 |
Damped Lyman-alpha system Damped Lyman alpha systems or Damped Lyman alpha absorption systems is a term used by astronomers for concentrations of neutral hydrogen gas that are detected in the spectra of quasars – a class of distant Active Galactic Nuclei. They are defined to be systems where the column density (density projected along the line of sight to the quasar) of hydrogen is larger than 2 x 10 atoms/cm. The observed spectra consist of neutral hydrogen Lyman alpha absorption lines which are broadened by radiation damping. These systems can be observed in quantity at relatively high redshifts of 2-4, when they contained most of the neutral hydrogen in the universe. They are believed to be associated with the early stages of galaxy formation, as the high neutral hydrogen column densities of DLAs are also typical of sightlines in the Milky Way, and other nearby galaxies. Since they are observed in absorption rather than by their stars, they offer the opportunity to study the dynamics of the gas in early galaxies directly. | https://en.wikipedia.org/wiki?curid=24053946 |
Spencer Lister Sir Frederick (8 April 1876 – 6 September 1939) was an English-born South African doctor and bacteriologist. Lister was born in Norwell, Nottinghamshire. In 1897 he joined West Hertfordshire Football Club (later Watford Football Club) as an amateur association football player, making twelve appearances and scoring three goals for the team in all competitions. He trained as a doctor at St Bartholomew's Hospital Medical College in London, qualifying in 1905. He then went to the Transvaal, serving as medical officer to the Premier Diamond Mines from 1907 to 1912 and to the Rand Gold Mines near Johannesburg from 1912 to 1917. In 1917 he was appointed Research Bacteriologist at the South African Institute for Medical Research in Johannesburg. He later became Director of the Institute and Professor of Pathology and Bacteriology at the University of the Witwatersrand. From 1928 he served on the South African Medical Council. He wrote important papers on pneumonia and influenza and was also an expert on leprosy. He was knighted in the 1920 New Year Honours, for services to bacteriology. Lister died of a heart attack in the library of the Institute for Medical Research. | https://en.wikipedia.org/wiki?curid=24055988 |
Houben-Weyl Methods of Organic Chemistry (Ger. "Methoden der Organischen Chemie") established in 1909 by the German chemist Theodor Weyl, is a classic chemistry text. It consisted initially of two volumes and covered literature published as early as 1834. Heinrich J. Houben revised and reissued it in 1913. It is considered one of the most significant resources for chemists. Up to the 4th edition the work was published in German by Thieme from 1952 to 1987, with supplementary volumes published between 1982 and 1999, some of them (from 1990 on) in English. It consists of 16 volumes, some of which are further divided. Overall, the 4th edition consists of 90 individual books. A new English-language edition was published by Thieme from 2000 to 2010 as "Science of Synthesis" in 48 volumes. It is constantly updated. | https://en.wikipedia.org/wiki?curid=24063825 |
Mixed-mating model The mixed-mating model is a mathematical model that describes the mating system of a plant population in terms of degree of self-fertilisation. It is a fairly simplistic model, employing several simplifying assumptions, most notably the assumption that every fertilisation event may be classed as either self-fertilisation, or outcrossing with a completely random mate. Thus the only model parameter to be estimated is the probability of self-fertilisation. The mixed mating model originated in the 1910s, with plant breeders who were seeking evidence of outcrossing contamination of self-pollinating crops, but a formal description of the model and its parameter estimation was not published until 1951. The model is still in common use today, though a number of more complex models are also now in use. For example, a weakness of the model lies in its assumption that inbreeding occurs only as a result of self-fertilisation; in reality, inbreeding may also occur through outcrossing between closely related individuals. The effective selfing model relaxes this assumption by seeking also to estimate the degree of shared ancestry of outcrossing mates. | https://en.wikipedia.org/wiki?curid=24065513 |
London Bioscience Innovation Centre LBIC, the London BioScience Innovation Centre is a hub providing laboratory and office facilities for biotech start-up companies based in Central London. LBIC, the London BioScience Innovation Centre, was created in 2000 as a response to the shortage of accommodation for life sciences activity in Central London. It received funding from the London Development Agency to fulfil its objective of developing a commercial life sciences cluster in London. LBIC is owned by the Royal Veterinary College and is housed at its campus in Camden. Its close relationship and proximity with the Royal Veterinary College facilitate research collaborations. LBIC houses a range of companies. The client list since 2000 includes: Biotechnology/Biomedicine Companies Consultancy Services Product Supplier Contract Research | https://en.wikipedia.org/wiki?curid=24065580 |
Effective selfing model The effective selfing model is a mathematical model that describes the mating system of a plant population in terms of the degree of self-fertilisation present. It was developed in the 1980s by Kermit Ritland, as an alternative to the simplistic mixed mating model. The mixed mating model assumes that every fertilisation event may be classed as either self-fertilisation, or outcrossing with a completely random mate. That is, it assumes that inbreeding is caused solely by self-fertilisation. This assumption is often violated in wild plant populations, where inbreeding may be due to outcrossing between closely related plants. For example, in dense stands, mating often occurs between plants in close proximity; and in plants with short seed dispersal distances, plants are often closely related to their nearest neighbours. When both these criteria are met, plants will tend to be closely related to the near neighbours with which they mate, resulting in significant inbreeding. In such a scenario, the mixed mating model will attribute all inbreeding to self-fertilisation, and therefore overestimate the extent of self-fertilisation occurring. The effective selfing model takes into account the potential for inbreeding to occur as a result of outcrossing between closely related plants, by considering the extent of kinship between mates. Ultimately, it is not possible to tease apart the two potential causes of inbreeding, and attributed the observed inbreeding to one cause or the other | https://en.wikipedia.org/wiki?curid=24073609 |
Effective selfing model Therefore, just as with the mixed mating model, in the effective selfing model there is only one parameter to be estimated. However this parameter, termed the effective selfing rate, is often a more accurate measure of the proportion of self-fertilisation than the corresponding parameter in the mixed mating model. | https://en.wikipedia.org/wiki?curid=24073609 |
Max Poll Max Fernand Leon Poll (21 July 1908 – 13 March 1991) was a Belgian ichthyologist who specialised in the Cichlidae. In the years 1946 and 1947 he organised an expedition to Lake Tanganyika. He has described several species of Pseudocrenilabrinae, such as "Lamprologus signatus", "Steatocranus casuarius", "Neolamprologus brichardi", and "Neolamprologus pulcher". Named after him are species and taxa such as "Etmopterus polli" , "Merluccius polli" , "Pollichthys" , "Polyipnus polli" , "Microsynodontis polli" , and "Synodontis polli" . He was a member of The Royal Academies for Science and the Arts of Belgium, professor at Université Libre de Bruxelles, and conservator at Musée Royal du Congo Belge in Tervuren. He was an honorary member of the American Society of Ichthyologists and Herpetologists. | https://en.wikipedia.org/wiki?curid=24074617 |
Pollinator exclusion experiment Pollinator exclusion experiments are experiments used by ecologists to determine the effectiveness of putative plant pollination vectors. Essentially, certain pollinators are prevented from visiting certain flowers, and observations are then made on which flowers develop seeds. If the exclusion of a certain class of visitor prevents or greatly reduces flower fertilisation rates, then it can be concluded that that class of visitor plays an important role in pollination. There are various methods for excluding pollinators. A cage may exclude nectarivorous birds and mammals but allow access by insects. A net may exclude all but the smallest animals, yet permit wind-pollination. Insect repellent may prevent visits by insects whilst allowing access by birds and mammals. Bags may be used to prevent all but autogamous pollination. Bagging flowers only during the day or night makes it possible to exclude diurnal or nocturnal visitors respectively. | https://en.wikipedia.org/wiki?curid=24075281 |
David J. Gower is a palaeontologist. Before making his debut for the Strongroom CC in 2000, he was a herpetology researcher at the Museum of Natural History in London. | https://en.wikipedia.org/wiki?curid=24077640 |
Lodos The lodos is the strong south-westerly wind which may predominate episodically in the Aegean Sea and Marmara Sea as well as the Mediterranean coast of Turkey all the year round; it frequently raises high seas and may give violent westerly squalls. The word "lodos" is Turkish, coming from Greek word "Notus", and originally means "southern wind". The predominant wind-driven surface current of the Aegean Sea is from northwest to southeast, but about twenty times a year the wind shifts southwards, pushing from the Mediterranean towards the Black Sea. If it continues long enough, the surface current also reverses, creating treacherous going for mariners. When is blowing, the winds in the Turkish Straits begin to shift during the early morning hours. The Black Sea’s currents are also affected by Lodos. They are at their strongest in the afternoon and often die down at night, but sometimes lodos winds last for days without a break. Similar winds blow in the Adriatic and Ionian maritime regions. winds are dangerous to sailors because they come up in clear weather without warning and can blow at 9-10 Beaufort. Most vessels cannot sail under such conditions. brings wind and waves from the south from October to April, with a peak season in December. Along with warm waters from the South, lodos also brings African dust from the Sahara Desert, which contains many minerals such as sulfate, iron, zinc and other minerals that are beneficial to plants | https://en.wikipedia.org/wiki?curid=24108802 |
Lodos If lodos persists for more than a day, these mineral-rich dusts cause headaches, bronchitis and other respiratory diseases. During strong lodos winds, especially in December, large vessels are warned against crossing the Bosphorus Strait and at times, the strait is closed to all naval traffic due to lodos shifting charted surface currents. Vessels are most vulnerable to these shifting currents if they lack speed or experience an engine failure. in which case the only means to halt a vessel would be anchoring, but there is not enough distance at Bosphorus for such a measure, and disaster becomes inevitable. | https://en.wikipedia.org/wiki?curid=24108802 |
Chinese Nuclear Society The (CNS; 中国核学会) is a non-profit organization representing individuals contributing to and supporting nuclear science, nuclear technology and nuclear engineering in China. It was established in 1980. Its objective is to promote the advancement and peaceful use of nuclear science and technology, undertake scientific and technical exchange, engage in public communication and enhance international cooperation and carries out Conferences, seminars, workshops, etc.; Transactions and publications; Lectures and materials to the public, media; Exhibitions; Visits to and from other overseas partners; Policy suggestions to government authorities. The membership of the Society consists of regular members, student members and organization members. Membership is open to any person or organization supporting the object of the Society and agreeing with the rules of the Society, each applicant for membership could submit an application to the Secretariat. The Society has about 8810 individual members and 45 organization members. The supreme authority in the Society is the National General Conference, and its executive body is the Board of Directors. The National General Conference is held every four years. The Secretariat under the leadership of the Board of Director is responsible for daily operation, and the Secretary General is the chief administrative officer of the Society | https://en.wikipedia.org/wiki?curid=24113755 |
Chinese Nuclear Society The Society has 7 committees carrying our specified functions of the Society, 20 technical divisions enhancing activities in specific areas of nuclear science and technology, 20 provincial branches serving members in geographical provinces. Committees: scientific exchange committee, public communication and inquiry committee, education and human resource committee, editorial committee, organization committee, financial committee, women-in-nuclear committee Technical Divisions: Calculation Physics, Isotope, Isotope Separation Technology, Nuclear Agronomy, Nuclear Chemical Engineering, Nuclear Chemistry and Radiochemistry, Nuclear Electronics and Nuclear Detection Techniques, Nuclear Fusion and Plasma Physics, Nuclear Industry Applications, Nuclear Materials, Nuclear Medicine, Nuclear Physics, Nuclear Power, Nuclear Science and Technology Information, Nuclear Techno-economics and Management, Particles Accelerator Technology, Radiation Protection, Radiation Research and Technology, Uranium Geology, Uranium Mining and Metallurgy. Provincial Branches: Anhui, Beijing, Fujian, Gansu, Guangdong, Guizhou, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shanghai, Shanxi, Shanxxi, Sichuan, Tianjin, Xinjiang, Zhejiang. Under each of Technical divisions and Provincial Branches, there are a number of committees focusing on specific technical area. | https://en.wikipedia.org/wiki?curid=24113755 |
Walter Minder (August 6, 1905 – April 1, 1992) was a Swiss mineralogist and chemist. He together with Alice Leigh-Smith announced the discovery of element 85 (now called astatine) in 1940 and 1942. He proposed the name helvetium in 1940 and anglohelvetium in 1942 for the new element. Later it was proven that in fact he had not discovered element 85. X | https://en.wikipedia.org/wiki?curid=24119248 |
Algae bioreactor An algae bioreactor is used for cultivating micro or macro algae. Algae may be cultivated for the purposes of biomass production (as in a seaweed cultivator), wastewater treatment, CO fixation, or aquarium/pond filtration in the form of an algae scrubber. Algae bioreactors vary widely in design, falling broadly into two categories: open reactors and enclosed reactors. Open reactors are exposed to the atmosphere while enclosed reactors, also commonly called photobioreactors, are isolated to varying extent from the atmosphere. Specifically, algae bioreactors can be used to produce fuels such as biodiesel and bioethanol, to generate animal feed, or to reduce pollutants such as NO and CO in flue gases of power plants. Fundamentally, this kind of bioreactor is based on the photosynthetic reaction which is performed by the chlorophyll-containing algae itself using dissolved carbon dioxide and sunlight energy. The carbon dioxide is dispersed into the reactor fluid to make it accessible for the algae. The bioreactor has to be made out of transparent material. The algae are photoautotroph organisms which perform oxygenic photosynthesis. The equation for photosynthesis: Some of the first experiments with the aim of cultivating algae were conducted in 1957 by the "Carnegie Institution" in Washington. In these experiments, monocellular Chlorella were cultivated by adding CO and some minerals. In the early days, bioreactors were used which were made of glass and later changed to a kind of plastic bag | https://en.wikipedia.org/wiki?curid=24128922 |
Algae bioreactor The goal of all this research has been the cultivation of algae to produce a cheap animal feed. Nowadays 3 basic types of algae photobioreactors have to be differentiated, but the determining factor is the unifying parameter – the available intensity of sunlight energy. A plate reactor simply consists of vertically arranged or inclined rectangular boxes which are often divided in two parts to effect an agitation of the reactor fluid. Generally these boxes are arranged into a system by linking them. Those connections are also used for making the process of filling/emptying, introduction of gas and transport of nutritive substances, easier. The introduction of the flue gas mostly occurs at the bottom of the box to ensure that the carbon dioxide has enough time to interact with algae in the reactor fluid. A tubular reactor consists of vertical or horizontal arranged tubes, connected together to a pipe system. The algae-suspended fluid is able to circulate in this tubing. The tubes are generally made out of transparent plastics or borosilicate glass and the constant circulation is kept up by a pump at the end of the system. The introduction of gas takes place at the end/beginning of the tube system. This way of introducing gas causes the problem of deficiency of carbon dioxide, high concentration of oxygen at the end of the unit during the circulation, and bad efficiency. A bubble column photo reactor consists of vertical arranged cylindrical column, made out of transparent material | https://en.wikipedia.org/wiki?curid=24128922 |
Algae bioreactor The introduction of gas takes place at the bottom of the column and causes a turbulent stream to enable an optimum gas exchange. At present these types of reactors are built with a maximum diameter of 20 cm to 30 cm in order to ensure the required supply of sunlight energy. The biggest problem with the sunlight determined construction is the limited size of the diameter. Feuermann et al. invented a method to collect sunlight with a cone shaped collector and transfer it with some fiberglass cables which are adapted to the reactor in order to enable constructions of a column reactor with wider diameters. - on this scale the energy consumption due to pumps etc. and the CO cost of manufacture may outweigh the CO captured by the reactor. The cultivation of algae in a photobioreactor creates a narrow range of industrial application possibilities. Some power companies already established research facilities with algae photobioreactors to find out how efficient they could be in reducing CO emissions, which are contained in flue gas, and how much biomass will be produced. Algae biomass has many uses and can be sold to generate additional income. The saved emission volume can bring an income too, by selling emission credits to other power companies. The utilisation of algae as food is very common in East Asian regions. Most of the species contain only a fraction of usable proteins and carbohydrates, and a lot of minerals and trace elements | https://en.wikipedia.org/wiki?curid=24128922 |
Algae bioreactor Generally, the consumption of algae should be minimal because of the high iodine content, particularly problematic for those with hyperthyroidism. Likewise, many species of diatomaceous algae produce compounds unsafe for humans. The algae, especially some species which contain over 50 percent oil and a lot of carbohydrates, can be used for producing biodiesel and bioethanol by extracting and refining the fractions. This point is very interesting, because the algae biomass is generated 30 times faster than some agricultural biomass, which is commonly used for producing biodiesel. | https://en.wikipedia.org/wiki?curid=24128922 |
Kodecyte A kodecyte (ko•de•cyte) is a living cell that has been modified (koded) by the incorporation of one or more function-spacer-lipid constructs (FSL constructs) to gain a new or novel biological, chemical or technological function. The cell is modified by the lipid tail of the FSL construct incorporating into the bilipid membrane of the cell. All kodecytes retain their normal vitality and functionality while gaining the new function of the inserted FSL constructs. The combination of dispersibility in biocompatible media, spontaneous incorporation into cell membranes, and apparent low toxicity, makes FSL constructs suitable as research tools and for the development of new diagnostic and therapeutic applications. Kode FSL constructs consist of three components; a functional moiety (F), a spacer (S) and a lipid (L). Function groups on FSL constructs that can be used to create kodecytes include saccharides (including ABO blood group-related determinants, sialic acids, hyaluronin polysaccharides), fluorophores, biotin, and a range of peptides. Although kodecytes are created by modifying natural cells, they are different from natural cells. For example, FSL constructs, influenced by the composition of the lipid tail, are laterally mobile in the membrane and some FSL constructs may also cluster due to the characteristics of the functional group (F) | https://en.wikipedia.org/wiki?curid=24135147 |
Kodecyte As FSL constructs are anchored in the membrane via a lipid tail (L) it is believed they do not participate in signal transduction, but may be designed to act as agonists or antagonists of the initial binding event. FSL constructs will not actively pass through the plasma membrane but may enter the cell via membrane invagination and endocytosis. The "koding" of cells is stable (subject to the rate of turnover of the membrane components). FSL constructs will remain in the membrane of inactive cells (e.g. red blood cells) for the life of the cell provided it is stored in lipid free media. In the peripheral circulation FSL constructs are observed to be lost from red cell kodecytes at a rate of about 1% per hour. The initial "koding" dose and the minimum level required for detection determine how long the presence of "kodecytes" in the circulation can be monitored. For red blood "kodecytes" reliable monitoring of the presence of the "kodecytes" for up to 3 days post intravenous administration has been demonstrated in small mammals. The spacer (S) of a FSL construct has been selected so as to have negligible cross-reactivity with serum antibodies so kodecytes can be used with undiluted serum. By increasing the length of the FSL spacer from 1.9 to 7.2 nm it has been shown sensitivity can improve two-fold in red cell agglutination based kodecyte assays. However, increasing the size of the spacer further from 7.2 to 11.5 nm did not result in any further enhancement | https://en.wikipedia.org/wiki?curid=24135147 |
Kodecyte To view a simple video explaining how Kode Technology works, click the following link: https://www.youtube.com/watch?v=TIbjAl5KYpA FSL constructs, when in solution (saline) and in contact, will spontaneously incorporate into cell membranes. The methodology involves simply preparing a solution of FSL construct(s) in the range of 1–1000 μg/mL, with the concentration used determining the amount of antigen present on the kodecyte. The ability to control antigen levels on the outside of a kodecyte has allowed for manufacture of quality control sensitivity systems and serologic teaching kits incorporating the entire range of serologic agglutination reactions. The actual concentration will depend on the construct and the quantity of construct required in the membrane. One part of FSL solution is added to one part of cells (up to 100% suspension) and they are incubated at a set temperature within the range of 4–37 °C (39–99 °F) depending on temperature compatibility of the cells being modified. The higher the temperature, the faster the rate of FSL insertion into the membrane. For red blood cells incubation for 2 hours at 37 °C achieves >95% FSL insertion with at least 50% insertion being achieved within 20 minutes. In general, for carbohydrate based FSLs insertion into red blood cells, incubation for 4 hours at room temperature or 20 hours at 4 °C are similar to one hour at 37 °C | https://en.wikipedia.org/wiki?curid=24135147 |
Kodecyte The resultant kodecytes do not required to be washed, however this option should be considered if an excess of FSL construct is used in the koding process. Kodecytes can also be created "in vivo" by injection of constructs directly into the circulation. However this process will modify all cells in contact with the constructs and usually require significantly more construct than "in vitro" preparation, as FSL constructs will preferentially associate with free lipids. The "in vivo" creation of kodecytes is untargeted and FSL constructs will insert into all cells non-specifically, but may show a preference for some cell types. Diagnostic serological analyses including flow cytometry and scanning electron microscopy usually can't see a difference between "kodecytes" and unmodified cells. However, when compared with natural cells there does appear to be a difference between IgM and IgG antibody reactivities when the functional group (F) is a monomeric peptide antigen. IgM antibodies appear to react poorly with kodecytes made with FSL peptides. Furthermore, FSL constructs may have a restricted antigen/epitope and may not react with a monoclonal antibody unless the FSL construct and monoclonal antibody are complementary. Kodecytes can be studied using standard histological techniques. Kodecytes can be fixed after "koding" subject to the functional moiety (F) of the FSL construct being compatible with the fixative | https://en.wikipedia.org/wiki?curid=24135147 |
Kodecyte However, freeze cut or formalin-fixed freeze cut tissues are required because the lipid based FSL constructs (and other glycolipids) will be leached from the "kodecytes" in paraffin imbedded samples during the deparaffination steps. Koded membranes are described by the construct and the concentration of FSL (in μg/mL) used to create them. For example, kodecytes created with a 100 μg/mL solution of FSL-A would be termed A100 kodecytes. If multiple FSL constructs were used then the definition is expanded accordingly, e.g. A100+B300 kodecytes are created with a solution containing 100 μg/mL solution of FSL-A and 300 μg/mL solution of FSL-B. The "+" symbol is used to separate the construct mixes, e.g. A100+B300. If FSL concentrations are constant then the μg/mL component of the terminology can be dropped, e.g. A kodecytes. Alternatively unrelated constructs such as FSL-A and FSL-biotin will create A+biotin kodecytes, etc. If different cells are used in the same study then inclusion of the cell type into the name is recommended, e.g. RBC A100 kodecytes vs WBC A100 kodecytes, or platelet A100 kodecytes, etc. Kode Technology has been used for the "in vitro" modification of murine embryos, spermatozoa, zebra fish, epithelial/endometrial cells and red blood cells to create cellular quality controls systems, serologic kits (teaching), rare antigen expression, add infectious markers onto cells, modified cell adhesion/interaction/separation/immobilisation, and labelling | https://en.wikipedia.org/wiki?curid=24135147 |
Kodecyte It has also been intravascularly infused for in vivo modification of blood cells and neutralisation of circulating antibodies and in "in vivo" imaging of circulating bone marrow kodecytes in zebrafish. Kode FSL constructs have also been applied to non-biological surfaces such as modified cellulose, paper, silica, polymers, natural fibers, glass and metals and has been shown to be ultra-fast in labelling these surfaces. | https://en.wikipedia.org/wiki?curid=24135147 |
Helvetium was the suggested name of chemical element number 85, now known as astatine, given to it by the Swiss chemist Walter Minder. Walter Minder announced the discovery in 1940. He chose the name based on "Helvetia", the Latin name for Switzerland, to honor his country of birth. In the year 1942 he together with Alice Leigh-Smith announced a second time the discovery of element number 85. This time he proposed the name anglohelvetium to honor also England, the home of Alice Leigh-Smith. Later it was proven that in fact he had not discovered element 85. | https://en.wikipedia.org/wiki?curid=24140523 |
Mache (unit) Mache (symbol ME from German Mache-Einheit, plural Maches) is an obsolete unit of volumic radioactivity named for the Austrian physicist Heinrich Mache. It was defined as the quantity of radon (ignoring its daughter isotopes; in practice, mostly radon-222) per litre of air which ionises a sustained current of 0.001 esu (0.001 StatAmpere). 1 ME = 3.64 Eman = 3.64×10 Ci/L = 13.4545 Bq/L. | https://en.wikipedia.org/wiki?curid=24142585 |
Columella (botany) Columella (in plants) is an axis of sterile tissue which passes through the center of the spore-case of mosses. The term columella is also used to refer to story 1 to story 4 (S1 - S4) cells in the root cap located apically of the quiescent centre. In fungi it refers to central vacuolated part in hyphae. | https://en.wikipedia.org/wiki?curid=24161202 |
Cyclic flower A cyclic flower is a flower type formed out of a series of whorls; sets of identical organs attached around the axis at the same point. Most flowers consist of a single whorl of sepals termed a calyx; a single whorl of petals termed a corolla; one or more whorls of stamens (together termed the androecium); and a single whorl of carpels termed the gynoecium. This is a cyclic arrangement. Some flowers contain flower parts with a spiral arrangement. Such flowers are not cyclic. However in the common case of spirally arranged sepals on an otherwise cyclic flower, the term hemicyclic may be used. The suffix -cyclic is used to denote the number of whorls contained within a flower. The most common case is the pentacyclic flower, which contains five whorls: a calyx, a corolla, two whorls of stamens, and a single whorl of carpels. Another common case is the tetracyclic flower, which contains only one whorl of stamens, and therefore only four whorls in total. Tricyclic flowers also occur, generally where there is a single undifferentiated perianth. Flowers with more than five whorls are also not uncommon. The greatest variation occurs in the calyx and the androecium. Calyces of up to nine whorls have been recorded, and up to 12 whorls of stamens have been observed. | https://en.wikipedia.org/wiki?curid=24162663 |
Allargentum is a mineral from the class of antimonides, superclass of sulfides and sulfosalts (sometimes ascribed to the natural elements and alloys class), with formula written as AgSb, where x = 0.09–0.16. This moderately rare mineral is found in silver ores and is therefore named from the Greek ἄλλος ("allos", "another") and the Latin "argentum" ("silver"). Its Vickers hardness is 172–203. | https://en.wikipedia.org/wiki?curid=24164156 |
Degradation (geology) In geology, degradation refers to the lowering of a fluvial surface, such as a stream bed or floodplain, through erosional processes. Degradation is the opposite of aggradation. Degradation is characteristic of channel networks in which either bedrock erosion is taking place, or in systems that are sediment-starved and are therefore entraining more material than they are depositing. When a stream degrades, it leaves behind a fluvial terrace. This can be further classified as a strath terrace—a bedrock terrace that may have a thin mantle of alluvium—if the river is incising through bedrock. These terraces may be dated with methods such as cosmogenic radionuclide dating, OSL dating, and paleomagnetic dating (using reversals in the Earth's magnetic field to constrain the timing of events) to find when a river was at a particular level and how quickly it is downcutting. | https://en.wikipedia.org/wiki?curid=24169775 |
The Cold and the Dark The Cold and the Dark: The World after Nuclear War is a 1984 book by Paul R. Ehrlich, Carl Sagan, Donald Kennedy, and Walter Orr Roberts. It makes dramatic long lasting climate predictions of the effect a nuclear winter would have on the Earth, an event that is suggested by the authors to follow both a city countervalue strike during a nuclear war, and especially following strikes on oil refineries and fuel depots. The book was released following a highly publicised 1983 study co-authored by Sagan published in the journal "Science". | https://en.wikipedia.org/wiki?curid=24170630 |
Adnation in Angiosperms is the fusion of two or more whorls of a flower, e.g. stamens to petals". This is in contrast to connation, the fusion among a single whorl. | https://en.wikipedia.org/wiki?curid=24172372 |
Sequanium was the proposed name for a new element found by the Romanian physicist Horia Hulubei in 1939. The name derived from the Latin word Sequana for the river Seine running through Paris where Hulubei worked at that time. Hulubei thought he had discovered element 93 in a tantalite sample from the French region Haute-Vienne. The element 93 was synthesised in 1940 and named neptunium. | https://en.wikipedia.org/wiki?curid=24180148 |
Sinlap is a circular depression on Titan, a natural satellite of Saturn. is centred at 11,3° latitude north and 16,0° longitude west, and measures 80 km in diameter. was discovered by the images transmitted by "Cassini". It is named after a Jingpo spirit. | https://en.wikipedia.org/wiki?curid=24181217 |
Yuri A. Barbanel (also Yuri A. Barbanel’, Yury Abramovich Barbanel) (8 April 1935 – 2 August 2016) was a distinguished Russian chemist born in 1935 in Leningrad (now St. Petersburg). He obtained a Master of Science in chemistry from A. A. Zhdanov Leningrad State University, now Saint Petersburg State University, in 1958 and his Ph.D. in 1964 and his D.Sc. in 1991. Barbanel was a scientist in the fundamental radiochemistry branch of the V.G. Khlopin Radium Institute in St. Petersburg until his retirement in 2011. His research interests included optical spectra induced by radioluminescence and coordination chemistry of the actinides, and absorption spectra of the actinides in molten salts. | https://en.wikipedia.org/wiki?curid=24198988 |
Headington stone is a limestone from the Headington Quarry area of Oxford, England. Around 160 million years ago, during the Late Jurassic period, Britain was located further south and was submerged beneath a subtropical sea. The warm conditions meant that coral reefs could flourish. When the coral died, it was buried under successive layers of sediment and other debris. After millions of years, this became fossilized. It formed the Corallian Limestone that is now beneath the Headington Quarry area of Oxford. Historically, there were a number of stone quarries in Headington Quarry. was traditionally used for a number of the older Oxford University college buildings. In 1396, stone from quarrying in Headington was used to build the bell-tower for New College. It was also used for Oxford's city walls. was used in the 1520s by Cardinal Wolsey to build his Cardinal College, now known as Christ Church. was particularly good for building since it can be cut in any direction and thus carved relatively easily. The stone was employed in buildings outside Oxford such as for Eton College and Windsor Castle. Later stone extracted from the quarry was of less good quality, for example, that used to build the lower part of the Radcliffe Camera. The stone was prone to erosion by pollution. | https://en.wikipedia.org/wiki?curid=24215538 |
Keiichi Aichi Aichi was born in Tokyo in 1880 and studied theoretical physics at University of Tokyo. He graduated in 1903 and in 1905 moved to Kyoto where he became an assistant professor at Kyoto University. Between 1908 and 1911 he studied in Germany and in 1912 defended his PhD at Tohoku Imperial University with recommendations from the chancellor. Soon after, he assumed the post of professor at the university's then newly established College of Science. In 1922, he served as an interpreter during the visit of Albert Einstein in Japan. Aichi died from food poisoning in 1923. His son was the politician Kiichi Aichi, who served consecutively as Minister for Foreign Affairs and Minister of Finance. | https://en.wikipedia.org/wiki?curid=24221301 |
Traité Élémentaire de Chimie Traité élémentaire de chimie (Elementary Treatise on Chemistry) is a textbook written by Antoine Lavoisier published in 1789 and translated into English by Robert Kerr in 1790 under the title Elements of Chemistry in a New Systematic Order containing All the Modern Discoveries. It is considered to be the first modern chemical textbook. The book defines an element as a single substance that can't be broken down by chemical analysis and from which all chemical compounds are formed, publishing his discovery that fermentation produces carbon dioxide (carbonic gas) and spirit of wine, saying that it is "more appropriately called by the Arabic word alcohol since it is formed from cider or fermented sugar as well as wine", and publishing the first chemical equation "grape must = carbonic acid + alcohol", calling this reaction "one of the most extraordinary in chemistry", noting "In these experiments, we have to assume that there is a true balance or equation between the elements of the compounds with which we start and those obtained at the end of the reaction." The book contains a list of 33 elements, only 23 of which are elements in the modern sense | https://en.wikipedia.org/wiki?curid=24232670 |
Traité Élémentaire de Chimie The elements given by Lavoisier are: light, caloric, oxygen, azote (nitrogen), hydrogen, sulphur, phosphorous (phosphorus), charcoal, muriatic radical (chloride), fluoric radical (fluoride), boracic radical, antimony, arsenic, bismuth, cobalt, copper, gold, iron, lead, manganese, mercury, molybdena (molybdenite), nickel, platina (platinum), silver, tin, (tungsten), zinc, lime, magnesia (magnesium), barytes (baryte), (clay or earth of alum), and silex. The law of conservation of mass, which in France is taught as Lavoisier's Law, in is paraphrased in the phrase ""Rien ne se perd, rien ne se crée, tout se transforme."" ("Nothing is lost, nothing is created, everything is transformed.") | https://en.wikipedia.org/wiki?curid=24232670 |
Enhydro agate Enhydro agates are nodules, agates, or geodes with water trapped inside its cavity. Enhydros are closely related to fluid inclusions, but are composed of chalcedony. The formation of enhydros is still an ongoing process, with specimens dated back to the Eocene Epoch. They are commonly found in areas with volcanic rock. Enhydro agates are made up of banded microcrystalline or cryptocrystalline quartz. The agate has a hollow center, partially containing water. Enhydro agates can also contain debris or petroleum. Because the cavity is not full, the agate can produce sound from being shaken. Agates vary in size. The largest recorded agate was found in Fuxin City, China, with a diameter of 63 cm and weighing 310 kg. Enhydros are formed when water rich in silica percolates through volcanic rock, forming layers of deposited mineral. As layers build up, the mineral forms a cavity in which the water becomes trapped. The cavity is then layered with the silica-rich water, forming its shell. Unlike fluid inclusions, the chalcedony shell is permeable, allowing water to enter and exit the cavity very slowly. The water inside of an enhydro agate is most times not the same water as when the formation occurred. During the formation of an enhydro agate, debris can get trapped in the cavity. Types of debris varies in every agate. | https://en.wikipedia.org/wiki?curid=24233854 |
Kenneth Ruud (born 16 September 1969) is a Norwegian chemist. He is a professor of chemistry at the University of Tromsø. He is author or coauthor of more than 150 scientific articles and director of the Centre for Theoretical and Computational Chemistry in Tromsø. In 2008, he was the recipient of the Dirac medal from the World Association of Theoretical and Computational Chemists. He is one of the main contributors to the DALTON program package. In 2012 he was elected fellow of the Norwegian Academy of Science and Letters. Since April 2010, Kenneth is president of the Norwegian Chemical Society. In February 2013, Kenneth was elected Prorektor (= Vicepresident) for research of the University of Tromsø. He will take up this function on August 1, 2013. | https://en.wikipedia.org/wiki?curid=24241408 |
Stratotype A stratotype or type section is a geological term that names the physical location or outcrop of a particular reference exposure of a stratigraphic sequence or stratigraphic boundary. If the stratigraphic unit is layered, it is called a stratotype, whereas the standard of reference for unlayered rocks is the type locality. | https://en.wikipedia.org/wiki?curid=24242250 |
Master of biological sciences A Master of Science in Biological Sciences is a specific degree to a Master's Degree in the field of the Biological Sciences. This is a higher degree taken up in the Graduate School provided by a university. This degree is usually specific to those who have accomplished their undergraduate studies in any field under the Natural Sciences. The advancement in the study of this field offers a lot more specific fields of study such as Plant Biology, Molecular Biology, and Animal Biology. It requires at least 2 years of graduate studies. It may or may not require any thesis or research work, depending on the program offered by the university. There are laboratory works, lectures, and research works involved in this degree. There are also examinations given to the graduate students. After one has finished their Master in Biological Sciences, they can become a researcher, a professor for undergraduate studies, or they can also pursue a higher education in Doctoral Studies. | https://en.wikipedia.org/wiki?curid=24260834 |
Sand geyser A sand geyser, sand fountain or sand blow is a geologic phenomena which occurs in association with earthquakes and other seismic events. In the geologic record, these are seen as clastic dikes. It is described as "a geyser of sand and water that shoots from the ground during a major earthquake." A quake can cause underlying sand to liquefy while pressure forces the eruption of the sand mixture to the surface. The mixture of sand and water can also contain dissolved gases such as methane and carbon dioxide. Some investigators have located soil formations that indicate the existence of past sand geysers in earthquake prone areas. NASA has proposed that the existence of sand geysers on the surface of Mars explains some of the seasonal variations of light and dark areas. Plume-like markings that begin to appear during the martian spring may be caused by solid CO transforming explosively into its gaseous state causing an eruption of soil materials. A 2008 video recorded one eruption in Saudi Arabia. Another lay commentator attributed a similar event to differences in air temperature between underground pockets of air and the air above the ground. The phenomenon was observed during an earthquake in New Zealand in 1987. | https://en.wikipedia.org/wiki?curid=24281365 |
MCAG group The is a group of Mycobacteria. It includes Mycobacterium chelonae and Mycobacterium abscessus. | https://en.wikipedia.org/wiki?curid=24305930 |
Skynd (crater) Skynd is a crater on the surface of Uranus' moon Umbriel. It is estimated to be between 72 and 110 km in diameter. Its center is located at . Skynd has a bright central or near central peak, which is one of the few bright albedo features on Umbriel that noticeably stands out against Umbriel's low albedo. The crater is named after Skynd, a troll who stole three wives of a man living in Englerup. Citations Sources | https://en.wikipedia.org/wiki?curid=24338056 |
Iquitos Satellite Laboratory (IQTLAB) The was established in 2002 in the city of Iquitos, Peru by doctor Margaret Kosek, biologist Maribel Paredes Olortegui, and nurse Pablo Peñataro Yori, with the collaboration of the Dr. Robert Gilman working group in Lima, Peru and the US Naval Medical Research Unit No. 6 (NAMRU-6) . The is supported through NIH and the Bill & Melinda Gates Foundation funded grants. The mission of IQTLAB is to improve understanding of health problems among vulnerable populations in order to identify sustainable solutions that improve their health, social and economic conditions. The IQTLAB team consists of experts from Asociación Benéfica Prisma, the University of Virginia, the Johns Hopkins Bloomberg School of Public Health, and the Tulane University School of Public Health and Tropical Medicine, among other universities and research institutions worldwide. IQTLAB utilizes a multidisciplinary approach that combines knowledge of the epidemiology of tropical infectious disease, malnutrition, intestinal infection, biostatistics, medical science, demography, ecology, and spatial data collection and analysis. The team is led by Margaret Kosek, MD, an associate professor of infectious disease at the University of Virginia Department of Medicine. The research center is approximately and is capable of conducting sophisticated laboratory diagnostics and experiments | https://en.wikipedia.org/wiki?curid=24358006 |
Iquitos Satellite Laboratory (IQTLAB) In addition to the laboratory, IQTLAB provides a vast array of support for scientific data collection, including GPS/GIS data collection, survey data collection, satellite image processing, and climate conditions (strategic deployment of weather monitoring systems). IQTLAB currently has a number of ongoing projects, including: Since its foundation, the has been the host and support of national and international students from undergraduate to master and MD/PhD programs. | https://en.wikipedia.org/wiki?curid=24358006 |
Charged Aerosol Release Experiment The also known as CARE, is a project run by NASA which will use a rocket to release dust in the upper atmosphere to form a dusty plasma in space. The clouds thus generated are intended to simulate naturally occurring phenomena called noctilucent clouds, which are the highest clouds in the atmosphere. The CARE experiment is intended to create an artificial dust layer at the boundary of space in a controlled sense, in order to "allow scientists to study different aspects of it, the turbulence generated on the inside, the distribution of dust particles and such." The dust cloud is generated using the Nihka motor dust generator. The dust cloud is composed of aluminum oxide, carbon monoxide, hydrogen chloride, water, and nitrogen, as well as smaller amounts of carbon dioxide, hydrogen, monatomic chlorine, and monatomic hydrogen. According to NASA, Spatial Heterodyne Imager for Mesospheric Radicals (SHIMMER ) instrument will track the CARE dust cloud for days or even months. The SHIMMER instrument has previously viewed natural noctilucent clouds for the past two years. The CARE will be the first space viewing of an artificial noctilucent cloud. The rocket was set to launch between 7:30 and 7:57 EDT on Tuesday Sept. 14, 2009 from NASA's Wallops Flight Facility in Virginia. | https://en.wikipedia.org/wiki?curid=24368723 |
Network covalent bonding A network solid or covalent network solid is a chemical compound (or element) in which the atoms are bonded by covalent bonds in a continuous network extending throughout the material. In a network solid there are no individual molecules, and the entire crystal or amorphous solid may be considered a macromolecule. Formulas for network solids, like those for ionic compounds, are simple ratios of the component atoms represented by a formula unit. Examples of network solids include diamond with a continuous network of carbon atoms and silicon dioxide or quartz with a continuous three-dimensional network of SiO units. Graphite and the mica group of silicate minerals structurally consist of continuous two-dimensional sheets covalently bonded within the layer, with other bond types holding the layers together. Disordered network solids are termed glasses. These are typically formed on rapid cooling of melts so that little time is left for atomic ordering to occur. | https://en.wikipedia.org/wiki?curid=24369901 |
Sumihiko Hatusima Hatsushima was born in Nagasaki Prefecture, Japan in 1906. His tertiary studies and early lectureship was at Kyushu Imperial University, where he was awarded a doctorate in 1942. He accompanied Ryōzō Kanehira on a collecting expedition in New Guinea in 1940. Hatsushima returned to Austronesia in a collecting expedition to The Philippines in 1964. Hatsushima died in 2008. | https://en.wikipedia.org/wiki?curid=24374551 |
Quaternary Geochronology is a peer-reviewed scientific journal addressing methods and results in the dating of samples from the Quaternary Period. | https://en.wikipedia.org/wiki?curid=24376818 |
North polar sequence The is a group of 96 stars that was used to define stellar magnitudes and colors. The cluster of stars lies within two degrees of the Northern Celestial pole. That fact makes them visible to everyone in the northern hemisphere. Originally proposed by Edward Charles Pickering, the system was used between 1900 and 1950. Today it has been replaced by the UBV photometric system. | https://en.wikipedia.org/wiki?curid=24379121 |
Photon bubble A photon bubble is a type of radiation-driven instability that can occur in the magnetized, radiation-supported gas surrounding neutron stars, black hole accretion disks or at the edge of ultra-compact HII regions around young, massive stars. The instability occurs as follows. A compressive magnetohydrodynamical wave propagating at right angles to the direction of propagation of the radiation creates variations in the density of the gas. More radiation is able to pass through the low density regions than through the high density regions, and the imbalance in radiation pressure acts to drive gas out of the low density regions, along the magnetic field lines. This further decreases the density of the low density regions, which in turn allows more radiation to propagate through them, leading to runaway growth of the instability. | https://en.wikipedia.org/wiki?curid=24408119 |
Diffraction tomography is an inverse scattering technique used to find the shape of a scattering object by illuminating it with probing waves and recording the reflections. It is based on the diffraction slice theorem and assumes that the scatterer is weak. It is closely related to X-ray tomography. | https://en.wikipedia.org/wiki?curid=24422329 |
Lucium was the proposed name for an alleged new element found by chemist Prosper Barrière in 1896 in the mineral monazite. Later, William Crookes confirmed that the new element was actually an impure sample of yttrium. | https://en.wikipedia.org/wiki?curid=24436674 |
Bioproducts or bio-based products are materials, chemicals and energy derived from renewable biological resources. Biological resources include agriculture, forestry, and biologically-derived waste, and there are many other renewable bioresource examples. One of the scientific terms used to denote renewable bioresources is lignocellulose. Lignocellulosic tissues are biologically-derived natural resources containing some of the main constituents of the natural world. 1) Holocellulose is the carbohydrate fraction of lignocellulose that includes cellulose, a common building block made of sugar (glucose) that is the most abundant biopolymer, as well as hemicellulose. 2) Lignin is the second most abundant biopolymer. Cellulose and lignin are two of the primary natural polymers used by plants to store energy as well as to give strength, as is the case in woody plant tissues. Other energy storage chemicals in plants include oils, waxes, fats, etc., and because these other plant compounds have distinct properties, they offer potential for a host of different bioproducts Conventional bioproducts and emerging bioproducts are two broad categories used to categorize bioproducts. Examples of conventional bio-based products include building materials, pulp and paper, and forest products. Examples of emerging bioproducts or biobased products include biofuels, bioenergy, starch-based and cellulose-based ethanol, bio-based adhesives, biochemicals, bioplastics, etc | https://en.wikipedia.org/wiki?curid=24446858 |
Bioproducts Emerging bioproducts are active subjects of research and development, and these efforts have developed significantly since the turn of the 20/21st century, in part driven by the price of traditional petroleum-based products, by the environmental impact of petroleum use, and by an interest in many countries to become independent from foreign sources of oil. derived from bioresources can replace much of the fuels, chemicals, plastics etc. that are currently derived from petroleum engineering (also referred to as bioprocess engineering) refers to engineering of bio-products from renewable bioresources. This pertains to the design, development and implementation of processes, technologies for the sustainable manufacture of materials, chemicals and energy from renewable biological resources. Also referred to as Bioprocess Engineering: Bioprocess Engineering is a specialization of Biotechnology, Chemical Engineering or Biological Engineering or of Agricultural Engineering. It deals with the design and development of equipment and processes for the manufacturing of products such as food, feed, pharmaceuticals, nutraceuticals, chemicals, and polymers and paper from biological materials. Bioprocees engineering is a conglomerate of mathematics, biology and industrial design, and consists of various spectrums like designing of Fermentors, study of fermentors (mode of operations etc.) | https://en.wikipedia.org/wiki?curid=24446858 |
Bioproducts It also deals with studying various biotechnological processes used in industries for large scale production of biological product for optimization of yield in the end product and the quality of end product. Bio process engineering may include the work of mechanical, electrical and industrial engineers to apply principles of their disciplines to processes based on using living cells or sub component of such cells Also referred to as Bioresource Engineering: Bioresource engineering is related to the applications of biological engineering, chemical engineering and agricultural engineering usually based on biological and/or agricultural feedstocks. Bioresource engineering is more general and encompasses a wider range of technologies and various elements such as biomass, biological waste treatment, bioenergy, biotransformations and bioresource systems analysis, and technologies associated with Thermochemical conversion technologies: combustion, pyrolysis, gasification, catalysis, etc. Biochemical conversion technologies: aerobic methods, anaerobic digestion, microbial growth processes, enzymatic methods, composting Products: fibre, fuels, feedstocks, fertilisers, building materials, polymers and other industrial products Management: modelling, systems analysis, decisions, support systems. The impact of urbanization and increasing demand for land, food, and water presents engineers in a world with serious challenges | https://en.wikipedia.org/wiki?curid=24446858 |
Bioproducts Little attention has been given to the interface between the biological world and traditional engineering in the past. It is the job of bioresource engineers to fill that gap. Agricultural and bioresource engineers develop efficient and environmentally-sensitive methods of producing food, fiber, timber, bio-based products and renewable energy sources for an ever-increasing world population. | https://en.wikipedia.org/wiki?curid=24446858 |
Johann Becker (entomologist) Johann Becker (1932–2004) was a Brazilian entomologist who made important contributions to the study of insects in Brazil. He worked at the National Museum of Brazil. The assassin bug "Ghilianella beckeri" was named after him. | https://en.wikipedia.org/wiki?curid=24449765 |
Alexander Callender Purdie (25 December 1824 – 24 June 1899) was a New Zealand naturalist and botanist. Purdie was born in the parish of Fenwick, East Ayrshire, Scotland. After his schooling he moved to Glasgow acquiring a trade as a wire worker which he pursued in England and Scotland for several years, while also following his interest in natural history. He emigrated with his wife Ellen in 1860 from Glasgow to New Zealand on the ship “"Pladda"”, and settled in Dunedin. Purdie was a foundation member of both the Otago Institute in 1869, of which he was elected Curator and Librarian in 1873, and the Dunedin Field Naturalists’ Club, in 1872. He also had a long association with the Otago Museum, of which he was caretaker or curator, and then with the University of Otago where he was Janitor until his retirement in 1893. He died in Dunedin survived by his son and daughter, his wife having died about nine years previously. Purdie was the original describer of the New Zealand little bittern ("Ixobrychus novaezelandiae" (Purdie, 1871)). He is commemorated in the name of the plants, "Helichrysum purdiei" and "Boronia purdieana". His son Alex Purdie (c.1861 - 1905) collected the type specimen of the moth species "Tmetolophota purdii" which was named in his honour by Richard William Fereday. | https://en.wikipedia.org/wiki?curid=24454232 |
Planetary boundaries is a concept involving Earth system processes which contain environmental boundaries, proposed in 2009 by a group of Earth system and environmental scientists led by Johan Rockström from the Stockholm Resilience Centre and Will Steffen from the Australian National University. The group wanted to define a "safe operating space for humanity" for the international community, including governments at all levels, international organizations, civil society, the scientific community and the private sector, as a precondition for sustainable development. The framework is based on scientific evidence that human actions since the Industrial Revolution have become the main driver of global environmental change. According to the paradigm, "transgressing one or more planetary boundaries may be deleterious or even catastrophic due to the risk of crossing thresholds that will trigger non-linear, abrupt environmental change within continental- to planetary-scale systems." The Earth system process boundaries mark the safe zone for the planet to the extent that they are not crossed. As of 2009, two boundaries have already been crossed, while others are in imminent danger of being crossed | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries In 2009, a group of Earth System and environmental scientists led by Johan Rockström from the Stockholm Resilience Centre and Will Steffen from the Australian National University collaborated with 26 leading academics, including Nobel laureate Paul Crutzen, Goddard Institute for Space Studies climate scientist James Hansen and the German Chancellor's chief climate adviser Hans Joachim Schellnhuber and identified nine "planetary life support systems" essential for human survival, attempting to quantify how far seven of these systems had been pushed already. They estimated how much further humans can go before planetary habitability is threatened. Estimates indicated that three of these boundaries—climate change, biodiversity loss, and the biogeochemical flow boundary—appear to have been crossed. The boundaries were "rough, first estimates only, surrounded by large uncertainties and knowledge gaps" which interact in complex ways that are not yet well understood. Boundaries were defined to help define a "safe space for human development", which was an improvement on approaches aiming at minimizing human impacts on the planet. The 2009 report was presented to the General Assembly of the Club of Rome in Amsterdam. An edited summary of the report was published as the featured article in a special 2009 edition of "Nature". alongside invited critical commentary from leading academics like Nobel laureate Mario J. Molina and biologist Cristián Samper | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries In 2015, a second paper was published in "Science" to update the Planetary Boundaries concept including regional boundaries and findings were presented at the World Economic Forum in Davos, January 2015. A 2018 study, co-authored by Rockström, calls into question the international agreement to limit warming to 2 degrees above pre-industrial temperatures set forth in the Paris Agreement. The scientists raise the possibility that even if greenhouse gas emissions are substantially reduced to limit warming to 2 degrees, that might be the "threshold" at which self-reinforcing climate feedbacks add additional warming until the climate system stabilizes in a hothouse climate state. This would make parts of the world uninhabitable, raise sea levels by up to , and raise temperatures by to levels that are higher than any interglacial period in the past 1.2 million years. Rockström notes that whether this would occur "is one of the most existential questions in science." Study author Katherine Richardson stresses, "We note that the Earth has never in its history had a quasi-stable state that is around 2 °C warmer than the preindustrial and suggest that there is substantial risk that the system, itself, will ‘want’ to continue warming because of all of these other processes – even if we stop emissions. This implies not only reducing emissions but much more.” The idea that our planet has limits, including the burden placed upon it by human activities, has been around for some time | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries In 1972, "The Limits to Growth" was published. It presented a model in which five variables: world population, industrialization, pollution, food production, and resources depletion, are examined, and considered to grow exponentially, whereas the ability of technology to increase resources availability is only linear. Subsequently, the report was widely dismissed, particularly by economists and businessmen, and it has often been claimed that history has proved the projections to be incorrect. In 2008, Graham Turner from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) published "A comparison of "The Limits to Growth" with thirty years of reality". Turner found that the observed historical data from 1970 to 2000 closely matches the simulated results of the "standard run" limits of growth model for almost all the outputs reported. "The comparison is well within uncertainty bounds of nearly all the data in terms of both magnitude and the trends over time." Turner also examined a number of reports, particularly by economists, which over the years have purported to discredit the limits-to-growth model. Turner says these reports are flawed, and reflect misunderstandings about the model. In 2010, Nørgård, Peet and Ragnarsdóttir called the book a "pioneering report", and said that it "has withstood the test of time and, indeed, has only become more relevant." "Our Common Future" was published in 1987 by United Nations' World Commission on Environment and Development | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries It tried to recapture the spirit of the Stockholm Conference. Its aim was to interlock the concepts of development and environment for future political discussions. It introduced the famous definition for sustainable development: Of a different kind is the approach made by James Lovelock. In the 1970s he and microbiologist Lynn Margulis presented the Gaia theory or hypothesis, that states that all organisms and their inorganic surroundings on Earth are integrated into a single self-regulating system. The system has the ability to react to perturbations or deviations, much like a living organism adjusts its regulation mechanisms to accommodate environmental changes such as temperature (homeostasis). Nevertheless, this capacity has limits. For instance, when a living organism is subjected to a temperature that is lower or higher than its living range, it can perish because its regulating mechanism cannot make the necessary adjustments. Similarly the Earth may not be able to react to large deviations in critical parameters. In his book "The Revenge of Gaia", he affirms that the destruction of rainforests and biodiversity, compounded with the increase of greenhouse gases made by humans, is producing global warming. The Holocene began about 10,000 years ago. It is the current interglacial period, and it has proven to be a relatively stable environment of the Earth | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries There have been natural environmental fluctuations during the Holocene, but the key atmospheric and biogeochemical parameters have been relatively stable. This stability and resilience has allowed agriculture to develop and complex societies to thrive. According to Rockström "et al.", we "have now become so dependent on those investments for our way of life, and how we have organized society, technologies, and economies around them, that we must take the range within which Earth System processes varied in the Holocene as a scientific reference point for a desirable planetary state." Since the industrial revolution, according to Paul Crutzen, Will Steffen and others, the planet has entered a new epoch, the Anthropocene. In the Anthropocene, humans have become the main agents of not only change to the Earth System but also the driver of Earth System "rupture", disruption of the Earth System's ability to be resilient and recover from that change. There have been well publicized scientific warnings about risks in the areas of climate change and stratospheric ozone. However, other biophysical Earth System processes are also important and have limits which are being exceeded. For example, since the advent of the Anthropocene, the rate at which species are being extinguished has increased over 100 times, and humans are now the driving force altering global river flows as well as water vapor flows from the land surface | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries Continuing pressure on the Earth System from human activities raises the possibility that further pressure could be destabilizing, and precipitate sudden or irreversible responses by the Earth System, shunting it towards a variation or mode that is dangerous to life including to human society, for example a Hothouse Earth mode. According to Rockström et al., "Up to 30% of all mammal, bird, and amphibian species will be threatened with extinction this century." It is difficult to restore a 'safe operating space' for humanity that is described by the planetary boundary concept, because the predominant paradigms of social and economic development are largely indifferent to the looming possibilities of large scale environmental disasters triggered by humans. Legal boundaries can help keep human activities in check, but are only as effective as the political will to make and enforce them. Thresholds and boundaries The "threshold", or tipping point, is the value at which a very small increment for the control variable (like CO) triggers a larger, possibly catastrophic, change in the response variable (global warming) through feedbacks in the natural Earth System itself. The threshold points are difficult to locate, because the Earth System is very complex. Instead of defining the threshold value, the study establishes a range, and the threshold is supposed to lie inside it. The lower end of that range is defined as the "boundary" | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries Therefore, it defines a 'safe operating space', in the sense that as long as we are below the boundary, we are below the threshold value. If the boundary is crossed, we enter into a danger zone. The proposed framework lays the groundwork for shifting approach to governance and management, away from the essentially sectoral analyses of limits to growth aimed at minimizing negative externalities, toward the estimation of the safe space for human development. define, as it were, the boundaries of the "planetary playing field" for humanity if major human-induced environmental change on a global scale is to be avoided Transgressing one or more planetary boundaries may be highly damaging or even catastrophic, due to the risk of crossing thresholds that trigger non-linear, abrupt environmental change within continental- to planetary-scale systems. The 2009 study identified nine planetary boundaries and, drawing on current scientific understanding, the researchers proposed quantifications for seven of them | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries These seven are climate change (CO concentration in the atmosphere < 350 ppm and/or a maximum change of +1 W/m in radiative forcing); ocean acidification (mean surface seawater saturation state with respect to aragonite ≥ 80% of pre-industrial levels); stratospheric ozone (less than 5% reduction in total atmospheric O from a pre-industrial level of 290 Dobson Units); biogeochemical nitrogen (N) cycle (limit industrial and agricultural fixation of N to 35 Tg N/yr) and phosphorus (P) cycle (annual P inflow to oceans not to exceed 10 times the natural background weathering of P); global freshwater use (< 4000 km/yr of consumptive use of runoff resources); land system change (< 15% of the ice-free land surface under cropland); and the rate at which biological diversity is lost (annual rate of < 10 extinctions per million species). The two additional planetary boundaries for which the group had not yet been able to determine a global boundary level are chemical pollution and atmospheric aerosol loading. Subsequent work on planetary boundaries begins to relate these thresholds at the regional scale. Figures and data for the updated Planetary Boundaries can be found at the Stockholm Resilience Centre website. Christopher Field, director of the Carnegie Institution's Department of Global Ecology, is impressed: "This kind of work is critically important. Overall, this is an impressive attempt to define a safety zone | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries " But the conservation biologist Stuart Pimm is not impressed: "I don’t think this is in any way a useful way of thinking about things... The notion of a single boundary is just devoid of serious content. In what way is an extinction rate 10 times the background rate acceptable?" and the environmental policy analyst Bill Clark thinks: "Tipping points in the earth system are dense, unpredictable... and unlikely to be avoidable through early warning indicators. It follows that... 'safe operating spaces' and 'planetary boundaries' are thus highly suspect and potentially the new 'opiates'." The biogeochemist William Schlesinger queries whether thresholds are a good idea for pollutions at all. He thinks waiting until we near some suggested limit will just permit us to continue to a point where it is too late. "Management based on thresholds, although attractive in its simplicity, allows pernicious, slow and diffuse degradation to persist nearly indefinitely." The hydrologist David Molden thinks planetary boundaries are a welcome new approach in the 'limits to growth' debate. "As a scientific organizing principle, the concept has many strengths ... the numbers are important because they provide targets for policymakers, giving a clear indication of the magnitude and direction of change. They also provide benchmarks and direction for science. As we improve our understanding of Earth processes and complex inter-relationships, these benchmarks can and will be updated .. | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries we now have a tool we can use to help us think more deeply—and urgently—about planetary limits and the critical actions we have to take." The ocean chemist Peter Brewer queries whether it is "truly useful to create a list of environmental limits without serious plans for how they may be achieved ... they may become just another stick to beat citizens with. Disruption of the global nitrogen cycle is one clear example: it is likely that a large fraction of people on Earth would not be alive today without the artificial production of fertilizer. How can such ethical and economic issues be matched with a simple call to set limits? ... food is not optional." The environment advisor Steve Bass says the "description of planetary boundaries is a sound idea. We need to know how to live within the unusually stable conditions of our present Holocene period and not do anything that causes irreversible environmental change ... Their paper has profound implications for future governance systems, offering some of the 'wiring' needed to link governance of national and global economies with governance of the environment and natural resources. The planetary boundaries concept should enable policymakers to understand more clearly that, like human rights and representative government, environmental change knows no borders." The climate change policy advisor Adele Morris thinks that price-based policies are also needed to avoid political and economic thresholds | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries "Staying within a 'safe operating space' will require staying within all the relevant boundaries, including the electorate’s willingness to pay." In their report (2012) entitled "Resilient People, Resilient Planet: A future worth choosing", The High-level Panel on Global Sustainability called for bold global efforts, "including launching a major global scientific initiative, to strengthen the interface between science and policy. We must define, through science, what scientists refer to as "planetary boundaries", "environmental thresholds" and "tipping points"." In 2011, at their second meeting, the High-level Panel on Global Sustainability of the United Nations had incorporated the concept of planetary boundaries into their framework, stating that their goal was: "To eradicate poverty and reduce inequality, make growth inclusive, and production and consumption more sustainable while combating climate change and respecting the range of other planetary boundaries." Elsewhere in their proceedings, panel members have expressed reservations about the political effectiveness of using the concept of "planetary boundaries": "are still an evolving concept that should be used with caution [...] The planetary boundaries question can be divisive as it can be perceived as a tool of the "North" to tell the "South" not to follow the resource intensive and environmentally destructive development pathway that rich countries took themselves.. | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries This language is unacceptable to most of the developing countries as they fear that an emphasis on boundaries would place unacceptable brakes on poor countries." However, the concept is routinely used in the proceedings of the United Nations, and in the "UN Daily News". For example, the UNEP Executive Director Achim Steiner states that the challenge of agriculture is to "feed a growing global population without pushing humanity's footprint beyond planetary boundaries." The United Nations Environment Programme (UNEP) Yearbook 2010 also repeated Rockström's message, conceptually linking it with ecosystem management and environmental governance indicators. The planetary boundaries concept is also used in proceedings by the European Commission, and was referred to in the European Environment Agency synthesis report "The European environment – state and outlook 2010". Radiative forcing is a measure of the difference between the incoming radiation energy and the outgoing radiation energy acting across the boundary of the earth. Positive radiative forcing results in warming. From the start of the industrial revolution in 1750 to 2005, the increase in atmospheric carbon dioxide has led to a positive radiative forcing, averaging about 1.66 W/m². The climate scientist Myles Allen thinks setting "a limit on long-term atmospheric carbon dioxide concentrations merely distracts from the much more immediate challenge of limiting warming to 2 °C | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries " He says the concentration of carbon dioxide is not a control variable we can "meaningfully claim to control", and he questions whether keeping carbon dioxide levels below 350 ppm will avoid more than 2 °C of warming. Adele Morris, policy director, Climate and Energy Economics Project, Brookings Institution, makes a criticism from the economical-political point of view. She puts emphasis in choosing policies that minimize costs and preserve consensus. She favors a system of green-house gas emissions tax, and emissions trading, as ways to prevent global warming. She thinks that too-ambitious objectives, like the boundary limit on CO, may discourage such actions. According to the biologist Cristián Samper, a " boundary that expresses the probability of families of species disappearing over time would better reflect our potential impacts on the future of life on Earth." Since the industrial revolution, the Earth's nitrogen cycle has been disturbed even more than the carbon cycle. "Human activities now convert more nitrogen from the atmosphere into reactive forms than all of the Earth´s terrestrial processes combined. Much of this new reactive nitrogen pollutes waterways and coastal zones, is emitted back to the atmosphere in changed forms, or accumulates in the terrestrial biosphere." Only a small part of the fertilizers applied in agriculture is used by plants. Most of the nitrogen and phosphorus ends up in rivers, lakes and the sea, where excess amounts stress aquatic ecosystems | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries For example, fertilizer which discharges from rivers into the Gulf of Mexico has damaged shrimp fisheries because of hypoxia. The biogeochemist William Schlesinger thinks waiting until we near some suggested limit for nitrogen deposition and other pollutions will just permit us to continue to a point where it is too late. He says the boundary suggested for phosphorus is not sustainable, and would exhaust the known phosphorus reserves in less than 200 years. Peak phosphorus is a concept to describe the point in time at which the maximum global phosphorus production rate is reached. Phosphorus is a scarce finite resource on earth and means of production other than mining are unavailable because of its non-gaseous environmental cycle. According to some researchers, Earth's phosphorus reserves are expected to be completely depleted in 50–100 years and peak phosphorus to be reached in approximately 2030. Surface ocean acidity has increased thirty percent since the industrial revolution. About one quarter of the additional carbon dioxide generated by humans is dissolved in the oceans, where it forms carbonic acid. This acidity inhibits the ability of corals, shellfish and plankton to build shells and skeletons. Knock-on effects could have serious consequences for fish stocks. This boundary is clearly interconnected with the climate change boundaries, since the concentration of carbon dioxide in the atmosphere is also the underlying control variable for the ocean acidification boundary | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries The ocean chemist Peter Brewer thinks "ocean acidification has impacts other than simple changes in pH, and these may need boundaries too." Across the planet, forests, wetlands and other vegetation types are being converted to agricultural and other land uses, impacting freshwater, carbon and other cycles, and reducing biodiversity. The environment advisor Steve Bass says research tells us that "the sustainability of land use depends less on percentages and more on other factors. For example, the environmental impact of 15 per cent coverage by intensively farmed cropland in large blocks will be significantly different from that of 15 per cent of land farmed in more sustainable ways, integrated into the landscape. The boundary of 15 per cent land-use change is, in practice, a premature policy guideline that dilutes the authors' overall scientific proposition. Instead, the authors might want to consider a limit on soil degradation or soil loss. This would be a more valid and useful indicator of the state of terrestrial health." Human pressures on global freshwater systems are having dramatic effects. The freshwater cycle is another boundary significantly affected by climate change. Freshwater resources, such as lakes and aquifers, are usually renewable resources which naturally recharge (the term fossil water is sometimes used to describe aquifers which don't recharge). Overexploitation occurs if a water resource is mined or extracted at a rate that exceeds the recharge rate | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries Recharge usually comes from area streams, rivers and lakes. Forests enhance the recharge of aquifers in some locales, although generally forests are a major source of aquifer depletion. Depleted aquifers can become polluted with contaminants such as nitrates, or permanently damaged through subsidence or through saline intrusion from the ocean. This turns much of the world's underground water and lakes into finite resources with peak usage debates similar to oil. Though Hubbert's original analysis did not apply to renewable resources, their overexploitation can result in a Hubbert-like peak. A modified Hubbert curve applies to any resource that can be harvested faster than it can be replaced. The hydrologist David Molden says "a global limit on water consumption is necessary, but the suggested planetary boundary of 4,000 cubic kilometres per year is too generous." The stratospheric ozone layer protectively filters ultraviolet radiation (UV) from the Sun, which would otherwise damage biological systems. The actions taken after the Montreal Protocol appeared to be keeping the planet within a safe boundary. However, in 2011, according to a paper published in "Nature", the boundary was unexpectedly pushed in the Arctic; "... the fraction of the Arctic vortex in March with total ozone less than 275 Dobson units (DU) is typically near zero, but reached nearly 45%" | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries The Nobel laureate in chemistry, Mario Molina, says "five per cent is a reasonable limit for acceptable ozone depletion, but it doesn't represent a tipping point". Aerosol particles in the atmosphere impact the health of humans and influence monsoon and global atmospheric circulation systems. Some aerosols produce clouds which cool the Earth by reflecting sunlight back to space, while others, like soot, produce thin clouds in the upper stratosphere which behave like a greenhouse, warming the Earth. On balance, anthropogenic aerosols probably produce a net negative radiative forcing (cooling influence). Worldwide each year, aerosol particles result in about 800,000 premature deaths. Aerosol loading is sufficiently important to be included among the planetary boundaries, but it is not yet clear whether an appropriate safe threshold measure can be identified. Some chemicals, such as persistent organic pollutants, heavy metals and radionuclides, have potentially irreversible additive and synergic effects on biological organisms, reducing fertility and resulting in permanent genetic damage. Sublethal uptakes are drastically reducing marine bird and mammal populations. This boundary seems important, although it is hard to quantify. A Bayesian emulator for persistent organic pollutants has been developed which can potentially be used to quantify the boundaries for chemical pollution | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries To date, critical exposure levels of polychlorinated biphenyls (PCBs) above which mass mortality events of marine mammals are likely to occur, have been proposed as a chemical pollution planetary boundary. A planetary boundary may interact in a manner that changes the safe operating level of other boundaries. Rockström "et al." 2009 did not analyze such interactions, but they suggested that many of these interactions will reduce rather than expand the proposed boundary levels. For example, the land use boundary could shift downward if the freshwater boundary is breached, causing lands to become arid and unavailable for agriculture. At a regional level, water resources may decline in Asia if deforestation continues in the Amazon. Such considerations suggest the need for "extreme caution in approaching or transgressing any individual planetary boundaries." Another example has to do with coral reefs and marine ecosystems. In 2009, showed that, since 1990, calcification in the reefs of the Great Barrier that they examined decreased at a rate unprecedented over the last 400 years (14% in less than 20 years). Their evidence suggests that the increasing temperature stress and the declining ocean saturation state of aragonite is making it difficult for reef corals to deposit calcium carbonate. explored how multiple stressors, such as increased nutrient loads and fishing pressure, move corals into less desirable ecosystem states | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries showed that ocean acidification will significantly change the distribution and abundance of a whole range of marine life, particularly species "that build skeletons, shells, and tests of biogenic calcium carbonate. "Increasing temperatures, surface UV radiation levels and ocean acidity all stress marine biota, and the combination of these stresses may well cause perturbations in the abundance and diversity of marine biological systems that go well beyond the effects of a single stressor acting alone." In 2012 Kate Raworth from Oxfam noted the Rockstrom concept does not take human population growth into account. She suggested social boundaries should be incorporated into the planetary boundary structure, such as jobs, education, food, access to water, health services and energy and to accommodate an environmentally safe space compatible with poverty eradication and "rights for all". Within planetary limits and an equitable social foundation lies a doughnut shaped area which is the area where there is a "safe and just space for humanity to thrive in". An empirical application of the doughnut model by O'Neill et al. showed that so far across 150 countries not a single country satisfies its citizens' basic needs while maintaining a globally sustainable level of resource use. Several studies assessed environmental footprints of nations based on planetary boundaries: for Sweden, Switzerland, the Netherlands, the European Union as well as for the world’s most important economies | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries While the metrics and allocation approaches applied varied, there is a converging outcome that resource use of wealthier nations – if extrapolated to world population – is not compatible with planetary boundaries. In 2012, Steven Running suggested a tenth boundary, the annual net global primary production of all terrestrial plants, as an easily determinable measure integrating many variables that will give "a clear signal about the health of ecosystems". The United Nations secretary general Ban Ki-moon endorsed the concept of planetary boundaries on 16 March 2012, when he presented the key points of the report of his High Level Panel on Global Sustainability to an informal plenary of the UN General Assembly. Ban stated: "The Panel’s vision is to eradicate poverty and reduce inequality, to make growth inclusive and production and consumption more sustainable, while combating climate change and respecting a range of other planetary boundaries." The concept was incorporated into the so-called "zero draft" of the outcome of the United Nations Conference on Sustainable Development to be convened in Rio de Janeiro 20–22 June 2012. However, the use of the concept was subsequently withdrawn from the text of the conference, "partly due to concerns from some poorer countries that its adoption could lead to the sidelining of poverty reduction and economic development | https://en.wikipedia.org/wiki?curid=24458151 |
Planetary boundaries It is also, say observers, because the idea is simply too new to be officially adopted, and needed to be challenged, weathered and chewed over to test its robustness before standing a chance of being internationally accepted at UN negotiations." The planetary boundary framework was updated in 2015. It was suggested that three of the boundaries (including climate change) might push the Earth system into a new state if crossed; these also strongly influence the remaining boundaries. In the paper, the framework is developed to make it more applicable at the regional scale. Human activities related to agriculture and nutrition globally contribute to the transgression of four out of nine planetary boundaries. Surplus nutrient flows (N, P) into aquatic and terrestrial ecosystems are of highest importance, followed by excessive land-system change and biodiversity loss. Whereas in the case of biodiversity loss, P cycle and land-system change, the transgression is in the zone of uncertainty—indicating an increasing risk (yellow circle in the figure), the N boundary related to agriculture is more than 200% transgressed—indicating a high risk (red marked circle in the figure). Here, nutrition includes food processing and trade as well as food consumption (preparation of food in households and gastronomy). Consumption-related environmental impacts are not quantified at the global level for the planetary boundaries of freshwater use, atmospheric aerosol loading (air pollution) and stratospheric ozone depletion. | https://en.wikipedia.org/wiki?curid=24458151 |
Translational regulation refers to the control of the levels of protein synthesized from its mRNA. This regulation is vastly important to the cellular response to stressors, growth cues, and differentiation. In comparison to transcriptional regulation, it results in much more immediate cellular adjustment through direct regulation of protein concentration. The corresponding mechanisms are primarily targeted on the control of ribosome recruitment on the initiation codon, but can also involve modulation of peptide elongation, termination of protein synthesis, or ribosome biogenesis. While these general concepts are widely conserved, some of the finer details in this sort of regulation have been proven to differ between prokaryotic and eukaryotic organisms. Initiation of translation is regulated by the accessibility of ribosomes to the Shine-Dalgarno sequence. This stretch of four to nine purine residues are located upstream the initiation codon and hybridize to a pyrimidine-rich sequence near the 3' end of the 16S RNA within the 30S bacterial ribosomal subunit. Polymorphism in this particular sequence has both positive and negative effects on the efficiency of base-pairing and subsequent protein expression. Initiation is also regulated by proteins known as initiation factors which provide kinetic assistance to the binding between the initiation codon and tRNA, which supplies the 3'-UAC-5' anticodon. IF1 binds the 30S subunit first, instigating a conformational change that allows for the additional binding of IF2 and IF3 | https://en.wikipedia.org/wiki?curid=24467949 |
Translational regulation IF2 ensures that tRNA remains in the correct position while IF3 proofreads initiation codon base-pairing to prevent non-canonical initiation at codons such as AUU and AUC. Generally, these initiation factors are expressed in equal proportion to ribosomes, however experiments using cold-shock conditions have shown to create stoichiometric imbalances between these translational machinery. In this case, two to three fold changes in expression of initiation factors coincide with increased favorability towards translation of specific cold-shock mRNAs. Due to the fact that translation elongation is an irreversible process, there are few known mechanisms of its regulation. However, it has been shown that translational efficiency is reduced via diminished tRNA pools, which are required for the elongation of polypeptides. In fact, the richness of these tRNA pools are susceptible to change through cellular oxygen supply. The termination of translation requires coordination between release factor proteins, the mRNA sequence, and ribosomes. Once a termination codon is read, release factors RF-1, RF-2, and RF-3 contribute to the hydrolysis of the growing polypeptide, which terminates the chain. Interestingly, bases downstream the stop codon affect the activity of these release factors. In fact, some bases proximal to the stop codon suppress the efficiency of translation termination by reducing the enzymatic activity of the release factors | https://en.wikipedia.org/wiki?curid=24467949 |
Translational regulation For instance, the termination efficiency of a UAAU stop codon is near 80% while the efficiency of UGAC as a termination signal is only 7%. When comparing initiation in eukaryotes to prokaryotes, perhaps one of the first noticeable differences is the use of a larger 80S ribosome. Regulation of this process begins with the supply of methionine by a tRNA anticodon that basepairs AUG. This base pairing comes about by the scanning mechanism that ensues once the small 40S ribosomal subunit binds the 5' untranslated region (UTR) of mRNA. The usage of this scanning mechanism, in opposition to the Shine-Dalgarno sequence that was referenced in prokaryotes, is the ability to regulate translation through upstream RNA secondary structures. Interestingly, this inhibition of initiation through complex RNA structures may be circumvented in some cases by way of internal ribosomal entry sites (IRESs) that localize pre-initiation complexes (PIC) to the start site. In addition to this, the guidance of the PIC to the 5' UTR is coordinated by subunits of the PIC, known as eukaryotic initiation factors (eIFs). When some of these proteins are down-regulated through stresses, translation initiation is reduced by inhibiting cap dependent initiation, the activation of translation by binding eIF4E to the 5' 7-methylguanylate cap. eIF2 is responsible for coordinating the interaction between the Met-tRNA and the P-site of the ribosome | https://en.wikipedia.org/wiki?curid=24467949 |
Translational regulation Regulation by phosphorylation of eIF2 is largely associated with the termination of translation initiation. Serine kinases, GCN2, PERK, PKR, and HRI are examples of detection mechanisms for differing cellular stresses that respond by slowing translation through eIF2 phosphorylation. The hallmark difference of elongation in eukaryotes in comparison to prokaryotes is its separation from transcription. While prokaryotes are able to undergo both cellular processes simultaneously, the spatial separation that is provided by the nuclear membrane prevents this coupling in eukaryotes. Eukaryotic elongation factor 2 (eEF2) is a regulateable GTP-dependent translocase that moves nascent polypeptide chains from the A-site to the P-site in the ribosome. Phosphorylation of threonine 56 is inhibitory to the binding of eEF2 to the ribosome. Cellular stressors, such as anoxia have proven to induce translational inhibition through this biochemical interaction. Mechanistically, eukaryotic translation termination matches its prokaryotic counterpart. In this case, termination of the polypeptide chain is achieved through the hydrolytic action of a heterodimer consisting of release factors, eRF1 and eRF3. Translation termination is said to be leaky in some cases as noncoding-tRNAs may compete with release factors to bind stop codons. This is possible due to the matching of 2 out 3 bases within the stop codon by tRNAs that may occasionally outcompete release factor base pairing | https://en.wikipedia.org/wiki?curid=24467949 |
Translational regulation An example of regulation at the level of termination is functional translational readthrough of the lactate dehydrogenase gene LDHB. This readthrough provides a peroxisomal targeting signal that localizes the distinct LDHBx to the peroxisome. Translation in plants is tightly regulated as in animals, however, it is not as well understood as transcriptional regulation. There are several levels of regulation including translation initiation, mRNA turnover and ribosome loading. Recent studies have shown that translation is also under the control of the circadian clock. Like transcription, the translation state of numerous mRNAs changes over the diel cycle (day night period). | https://en.wikipedia.org/wiki?curid=24467949 |
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