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70,607,660 | https://en.wikipedia.org/wiki/Phalaenopsis%20%C3%97%20leucorrhoda | Phalaenopsis × leucorrhoda is a species of orchid native to the Philippines. It is a natural hybrid of Phalaenopsis aphrodite and Phalaenopsis schilleriana.
Etymology
The specific epithet leucorrhoda, composed of leuco meaning white and rhodo meaning rose-coloured, is derived from the floral colouration.
Taxonomy
It has been confused with Phalaenopsis philippinensis, from which it differs in regard to the morphology of the callus of the labellum.
References
leucorrhoda
Orchid hybrids
Hybrid plants
Plant nothospecies
Interspecific plant hybrids
Plants described in 1875
Orchids of the Philippines | Phalaenopsis × leucorrhoda | [
"Biology"
] | 141 | [
"Hybrid plants",
"Plants",
"Hybrid organisms"
] |
70,607,970 | https://en.wikipedia.org/wiki/Phalaenopsis%20%C3%97%20rolfeana | Phalaenopsis × rolfeana is a species of orchid native to the Philippines. It is a hybrid of Phalaenopsis equestris and Phalaenopsis sanderiana.
Etymology
The specific epithet rolfeana honours the English botanist Robert Allen Rolfe, who specialised on the study of orchids. He had first described this taxon as Phalaenopsis × hebe, which however was a Nomen illegitimum and thus not accepted.
References
rolfeana
Orchid hybrids
Hybrid plants
Plant nothospecies
Interspecific plant hybrids
Plants described in 1969
Orchids of the Philippines | Phalaenopsis × rolfeana | [
"Biology"
] | 124 | [
"Hybrid plants",
"Plants",
"Hybrid organisms"
] |
70,608,126 | https://en.wikipedia.org/wiki/Amanda%20Bradford | Dr. Amanda Bradford is a marine mammal biologist who is currently researching cetacean population dynamics for the National Marine Fisheries Service of the National Oceanic and Atmospheric Administration. Bradford is currently a Research Ecologist with the Pacific Islands Fisheries Science Center's Cetacean Research Program. Her research primarily focuses on assessing populations of cetaceans, including evaluating population size, health, and impacts of human-caused threats, such as fisheries interactions. Bradford is a cofounder and organizer of the Women in Marine Mammal Science (WIMMS) Initiative.
Education
Undergraduate education
Bradford received her Bachelor of Science in Marine Biology from Texas A&M University in Galveston, Texas in 1998. She worked in the lab of Bernd Würsig.
While Bradford was an undergraduate, she was a volunteer at the Texas Marine Mammal Stranding Network from 1994 to 1998. Bradford, monitored live stranded delphinids and performed basic husbandry and life-support for bottlenose dolphins and false killer whales. Bradford also participated in marine mammal necropsies.
During her senior year, Bradford began analyzing photo-identification data from the western North Pacific population of gray whales. Shortly after graduation, Bradford traveled to northeastern Sakhalin Island in the Russian Far East to join a collaborative Russia-U.S. field study of these whales on their primary feeding ground. Once Bradford returned from the field, she spent a year as a research assistant for this project based at the Southwest Fisheries Science Center in La Jolla, California.
Graduate education
Bradford attended the University of Washington, School of Aquatic and Fishery Sciences (SAFS) in Seattle, Washington, receiving her Masters of Science in 2003 and then Doctorate of Philosophy (PhD) in 2011. Bradford studied under the late Glenn VanBlaricom for both degrees.
During her time at SAFS, Bradford spent 10 summers in the Russian Far East studying the endangered western population of gray whales. Bradford's graduate research focused on estimating survival, abundance, anthropogenic impacts, and body condition of these whales. Her results showed that calf survival in the population was notably low, the population numbered only around 100 whales in the early 2000s, whales were vulnerable to fishing gear entanglement and vessel collisions, and that body condition varied by season and year. Lactating females where found to have the poorest body condition and did not always appear to recover by the end of a feeding season. Bradford also studied the age at sexual maturity and the birth-interval of the western gray whales, both important parameters for understanding the dynamics of this endangered population.
Bradford spent a lot of time as a graduate student working on photo-identification of the western gray whale population and published a paper on how to identify calves based on their barnacle scars and pigmentation patterns.
Academic awards and honors
Bradford received the National Marine Fisheries Service - Sea Grant Joint Fellowship Program in Population and Ecosystem Dynamics and Marine Resource Economics. This fellowship is designed to support and train highly qualified PhD students to pursue careers in these fields.
Career and research
Graduate research and early career
The majority of Bradford's work while completing her PhD focused on the western gray whale population. While the population is currently listed as endangered on the Red List of the International Union for Conservation of Nature (IUCN) and considered to be increasing, when Bradford was researching them they were listed as critically endangered. Much of what is known about the western gray whales is a result of the work of Bradford and her international colleagues.
Western Gray Whale Advisory Panel - International Union for Conservation of Nature
Bradford was responsible for synthesizing data and assisting with population analyses for the Western Gray Whale Advisory Panel between 2007 and 2011. Bradford also participated in two ship-based western gray whale satellite tagging surveys off Sakhalin Island, Russia.
Western Gray Whale Project, Russia-U.S. Collaboration
Bradford participated and eventually lead western gray whale boat-based photo-identification and genetic-monitoring surveys between 1998 and 2010, which included her putting in over 1,500 hours of small boat work. Further, Bradford collected gray whale behavioral data and theodolite-tracked movement data. In addition to the gray whale work, Bradford collected information on spotted seals in the early years of the collaboration.
Pacific Islands Fisheries Science Center
Shortly before graduating with her PhD, Bradford took a position at the Pacific Islands Fisheries Science Center, a part of NOAA Fisheries. Bradford is in the Cetacean Research Program of the Protected Species Division, where she studies population dynamics and demography, line-transect abundance estimation, mark-recapture parameter estimation, and health and injury assessment.
Bradford's work has been relevant to estimating thee bycatch of false killer whales in the Hawaii-based deep-set longline fishery. False killer whales are known for depredating catch and bait in this fishery and due to this behavior, they are one of the most often accidentally caught marine mammals. Bradford was involved in a study of false killer whale behavior and interactions with the fisheries in an effort to try and reduce the bycatch of this species and achieve conservation goals.
Bradford has also been working on a population study of Megaptera novaeangeliae, the humpback whale, and coauthored a paper in 2020 on a newfound breeding ground for the endangered western North Pacific humpback whale population off the Marina Archipelago. In order to promote the recovery of this population, it is vital to know the full extent of their breeding grounds to be able to assess and eliminate threats.
Bradford regularly participates in ship-based and small boat surveys for cetaceans in the Pacific Islands region. She also plays a leading role in efforts to incorporate unmanned aircraft systems, automated photo-identification using machine learning, and open data science practices into the data collection and analysis workflows of the Cetacean Research program. She regularly gives presentations, contributes to web stories, and otherwise communicates to stakeholders and members of the public.
Outreach and service
Women in Marine Mammal Science
Bradford is a cofounder and organizer of Women in Marine Mammal Science (WIMMS), an initiative aimed at amplifying women and helping them advance their careers in the field of marine mammal science. The initiative was formed following a workshop in 2017 at the Society for Marine Mammalogy Biennial Conference on the Biology of Marine Mammals. The workshop focused on identifying barriers that women face in the marine mammal science field and provided strategies to overcome these barriers. As a part of WIMMS, Bradford conducted a survey and analyzed results on gender-specific experiences in marine mammal science.
In 2020, Bradford signed a petition to the Society of Marine Mammalogy asking for them to help eliminate unpaid research positions within the field as the prevalence of these positions decreases the accessibility of the field and limits the diversity and inclusion.
Society for Marine Mammalogy
Bradford served as the Student-Member-at-Large for the Society for Marine Mammalogy's Board of Governors from 2006 to 2008. Bradford served as the student representative, facilitated student participation in the Society, and promoted the growth of the student chapters.
Select publications
Bradford A. et al. (2021). Line-transect abundance estimates of cetaceans in U.S. waters around the Hawaiian Islands in 2002, 2010 and 2017. U.S. Department of Commerce, NOAA Tech. Memo. NMFS-PIFSC-115.52pp.
Bradford A. et al. (2020). Abundance estimates of false killers whales in Hawaiian waters and the broader central Pacific. U.S. Department of Commerce, NOAA Tech. Memo. NMFS-PIFSC-104.78pp
Hill M. and Bradford A. et al.(2020). Found: a missing breeding ground for endangered western North Pacific humpback whales in the Mariana Archipelago. Endangered Species Research. 91–103. 10.3354/esr01010.
Bradford A. et al. (2018). Abundance estimates for management of endangered false killer whales in the main Hawaiian Islands. Endangered Species Research 36:297-313.
Weller D. and Bradford A. et al. (2018). Prevalence of Killer Whale Tooth Rake Marks on Gray Whales off Sakhalin Island, Russia. Aquatic Mammals. 44. 643–652. 10.1578/AM.44.6.2018.643.
Bradford A. Forney K, Oleson E, Barlow J. (2017). Abundance estimates of cetaceans from a line-transect survey within the U.S. Hawaiian Islands Exclusive Economic Zone. Fishery Bulletin 115:129-142.
Bradford A. Forney K, Oleson E, Barlow J. (2014). Accounting for subgroup structure in line-transect abundance estimates of false killer whales (Pseudorca crassidens) in Hawaiian waters. PLoS ONE 9:e90464.
Bradford A. et al. (2012). Leaner leviathans: Body condition variation in a critically endangered whale population. Journal of Mammalogy. 93. 251–266. 10.1644/11-MAMM-A-091.1.
Bradford A, Weller D, Burdin A, Brownell R. (2011). Using barnacle and pigmentation characteristics to identify gray whale calves on their feeding grounds. Marine Mammal Science - MAR MAMMAL SCI. 27. 10.1111/j.1748-7692.2010.00413.x.
Bradford A. et al. (2009). Anthropogenic scarring of western gray whales (Eschrichtius robustus). Marine Mammal Science 25:161-175.
References
Marine biologists
Ecology
Population dynamics
Mammal conservation
Women marine biologists
Year of birth missing (living people)
Living people | Amanda Bradford | [
"Biology"
] | 1,967 | [
"Ecology"
] |
70,608,153 | https://en.wikipedia.org/wiki/Diploglossus%20microlepis | Diploglossus microlepis, the small-lipped galliwasp, is a species of lizard of the Diploglossidae family. Almost nothing is known about this species, as the holotype, captured in 1831, has no geographic note.
References
Diploglossus
Reptiles described in 1831
Taxa named by John Edward Gray
Species known from a single specimen | Diploglossus microlepis | [
"Biology"
] | 78 | [
"Individual organisms",
"Species known from a single specimen"
] |
70,608,205 | https://en.wikipedia.org/wiki/Phalaenopsis%20%C3%97%20lotubela | Phalaenopsis × lotubela is a species of epiphytic orchid native to the island Sumatra of Indonesia. It is a hybrid of Phalaenopsis cornu-cervi and Phalaenopsis javanica.
Discovery
This species was first noticed to be distinct in 2018 by Gus Benk, who had found it among other Phalaenopsis species, such as Phalaenopsis cornu-cervi, Phalaenopsis javanica and Phalaenopsis fimbriata. It had previously been known by local people.
Etymology
The specific epithet lotubela is derived from the name, which local people call this species. It refers to the hill, where it was found.
Description
Phalaenopsis × lotubela is an epiphytic plant with 5–7, 12–20 cm long and 6–9 cm wide leaves. The pendent, 14–18 cm long inflorescence bears 5–10, sequentially opening, 3-3.5 cm wide flowers with a yellow ground colour and redish brown transverse barring. The sepals have acute tips. The labellum, which bears white trichomes, is 1 cm long and 0.5 cm wide.
References
lotubela
Orchid hybrids
Hybrid plants
Plant nothospecies
Interspecific plant hybrids
Plants described in 2018
Orchids of Indonesia
Orchids of Sumatra | Phalaenopsis × lotubela | [
"Biology"
] | 283 | [
"Hybrid plants",
"Plants",
"Hybrid organisms"
] |
70,611,659 | https://en.wikipedia.org/wiki/Ormanc%C4%B1k%2C%20Savur | Ormancık () is a neighbourhood in the municipality and district of Savur, Mardin Province of Turkey. The village is populated by Kurds of the Dereverî tribe and had a population of 31 in 2021.
History
On 21 January 1994 it was reportedly attacked with grenades by the PKK. Nineteen people, composed of nine women, six children and four village guards - were killed in what Human Rights Watch described as a "massacre." There is speculation that the event was a chemical attack.
References
Kurdish settlements in Mardin Province
Neighbourhoods in Savur District
Massacres in Turkey
Massacres in 1994
1994 murders in Turkey
Kurdistan Workers' Party attacks
Chemical weapons attacks | Ormancık, Savur | [
"Chemistry"
] | 139 | [
"Chemical weapons attacks",
"Chemical weapons"
] |
70,612,211 | https://en.wikipedia.org/wiki/Teresa%20Rojas%20Rabiela | María Teresa Rojas Rabiela (born December 17, 1947) is an ethnologist, ethnohistorian, Emeritus National Researcher and Mexican academic, specializing in Chinampas of Mexico's Basin, history of agriculture, hydraulics, technology, and labor organization in Mesoamerica during pre-Columbian and colonial eras, as well as historical photography of Mexico's peasants and indigenous people. She is recognized as a pioneer in historical studies on earthquakes in Mexico. From 2018 to 2021, Rojas Rabiela was involved in the restoration of the section of the pre-Hispanic aqueduct of Tetzcotzinco, Texcoco, known as El caño quebrado (the broken pipe).
Education and academia
Rabiela obtained her bachelor's degree in ethnology from Escuela Nacional de Antropología e Historia, Mexico, with her thesis Aspectos tecnológicos de las obras hidráulicas en el Valle de México (English: Technological Aspects of Hydraulic Works in the Valley of Mexico) under the direction of ; before acquiring her master's degree at the same institution. She received her doctoral degree from Universidad Iberoamericana, with the thesis La agricultura mesoamericana en el siglo XVI (English: Mesoamerican Agriculture in the 16th century), directed by Pedro Carrasco. She studied under Guillermo Bonfil Batalla, , Pedro Armillas, Pedro Carrasco and William T. Sanders.
In 1973, she was appointed research professor at Centro de Investigaciones y Estudios Superiores en Antropología Social (English: Higher Anthropology Research and Studies Center, CIESAS, for its acronym in Spanish), and its CEO from 1990 to 1996.
Career
Rabiela has held managerial, advisory, academic and representative positions at Centro de Investigaciones y Estudios Superiores en Antropología Social, Mexico; Foro Consultivo Científico y Tecnológico (Scientific and Technological Consultative Forum) Mexico; Academia Mexicana de Ciencias (Mexican Academy of Science); Colegio de Etnólogos y Antropólogos Sociales (Ethnologists and Social Anthropologists Society) Mexico; Sistema Nacional de Investigadores (National System of Researchers) Mexico; the UNAM Instituto de Investigaciones Antropológicas (Institute of Anthropological Research-UNAM); the Archivo General de la Nación (Nation's General Archive) Mexico; Universidad Iberoamericana, El Colegio de México, El Colegio de San Luis and El Colegio de Michoacán.
Rabiela is the Water's Historical Archive's founder (National Water Commission, Mexico) and has directed the Agrarian General Archive project development (CIESAS- Registro Nacional Agrario, Mexico).
She has been editor of Historia de los Pueblos Indígenas de México (Mexico's Indigenous Peoples History) collection (twenty four volumes) with Mario Humberto Ruz Sosa, CIESAS - Comisión Nacional para el Desarrollo de los Pueblos Indígenas, Mexico; of Colección Agraria ( Agrarian Collection, seventeen volumes) CIESAS-Registro Nacional Agrario, Mexico; of Serie Biografías of Colegio de Etnólogos y Antropólogos Sociales; and the "Iconografía de la Luz" (Iconography of Light) photolibrary Nacho López electronic catalog, with Ignacio Gutiérrez Ruvalcaba, CIESAS-CDI in fifty five volumes.
Publications
Books
References
External links
Review of Cultura Hidráulica y Simbolismo Mesoamericano del Agua en el México Prehispánico (Hydraulic Culture and Mesoamerican Symbolism of Water in Pre-Hispanic Mexico. In Spanish) El Colegio de Michoacán.
Review of Vidas y bienes olvidados. Testamentos indígenas novohispanos (Forgotten lives and goods. Novohispano indigenous wills.) In Spanish.
Publican edición facsimilar del Catálogo de la Colección de Antropología del Museo Nacional (Published facsimile edition of the Catalog of the Anthropology Collection of the National Museum, Mexico. In Spanish)
1947 births
Living people
Scientists from Mexico City
Writers from Mexico City
Mexican anthropologists
Mexican women anthropologists
20th-century Mexican scientists
20th-century Mexican women scientists
21st-century Mexican women scientists
Mexican ethnologists
Women ethnologists
Social anthropologists
21st-century science writers
Women science writers
20th-century anthropologists
21st-century anthropologists
20th-century Mexican writers
21st-century Mexican women writers
21st-century Mexican scientists
National School of Anthropology and History alumni
Universidad Iberoamericana alumni | Teresa Rojas Rabiela | [
"Technology"
] | 986 | [
"Women science writers",
"Women in science and technology"
] |
70,614,658 | https://en.wikipedia.org/wiki/Paola%20Caselli | Paola Caselli (born 1966) is an Italian astronomer and astrochemist known for her research on molecular clouds, star formation and planet formation, and the astrochemistry behind the materials found within the Solar System. She is the director of the Max Planck Institute for Extraterrestrial Physics near Munich in Germany. She also holds an honorary professorship at Ludwig Maximilian University of Munich.
Education and career
Caselli was born on 26 July 1966 in Follonica, Italy, and as a teenager was inspired to work in space science and molecular clouds by a teacher who gave her Fred Hoyle's 1957 science fiction novel The Black Cloud to read. She earned a laurea in astronomy and physics in 1990, from the University of Bologna, and completed her Ph.D. there in 1994.
After postdoctoral research at the Center for Astrophysics Harvard & Smithsonian, she became a researcher at the Arcetri Observatory in Florence, Italy, in 1996, and remained there until 2005. For the next two years, she was a visiting scholar at the University of California, Berkeley and at Harvard University. In 2007 she became a professor of astronomy at the University of Leeds, and in 2011 became head of astrophysics at Leeds. She joined the Max Planck Institute for Extraterrestrial Physics as its director in 2014.
While continuing at the Max Planck Institute, she has also held temporary positions as Hasselblad Guest Professor at the Onsala Space Observatory in Sweden and as Blaauw Professor at the University of Groningen in the Netherlands.
References
1966 births
Living people
Italian astronomers
Italian women scientists
Astrochemists
University of Bologna alumni
Academics of the University of Leeds
Max Planck Society people
Max Planck Institute directors | Paola Caselli | [
"Chemistry"
] | 341 | [
"Astrochemists"
] |
70,615,229 | https://en.wikipedia.org/wiki/Ministry%20of%20Mines%20and%20Energy%20%28Namibia%29 | The Namibian Ministry of Mines and Energy (MME) was established at Namibian independence in 1990. The first Namibian minister of mines and energy was Andimba Toivo ya Toivo, a liberation fighter posthumously declared a national hero of Namibia. The mines and energy minister is Tom Alweendo.
Ministers
All mines and energy ministers in chronological order are:
See also
Mining in Namibia
Economy of Namibia
References
External links
Official website Ministry of Mines and Energy
Mines and Energy
Mines and Energy
Mining in Namibia
Economy of Namibia
1990 establishments in Namibia | Ministry of Mines and Energy (Namibia) | [
"Engineering"
] | 109 | [
"Energy organizations",
"Energy ministries"
] |
70,615,290 | https://en.wikipedia.org/wiki/Vivo%20X%20Fold | Vivo X Fold is an Android-based foldable smartphone developed and manufactured by Vivo. This phone announced on 11 April 2022. On 11 April 2022 was announced Vivo X Fold+ which is improved version of X Fold with more powerful GPU, bigger battery, faster charging and new red color.
References
Foldable smartphones
Android (operating system) devices
Mobile phones introduced in 2022
Mobile phones with 8K video recording | Vivo X Fold | [
"Technology"
] | 86 | [
"Crossover devices",
"Foldable smartphones"
] |
70,615,389 | https://en.wikipedia.org/wiki/Waist%20beads | Waist beads is a type of jewelry worn around the waist or on the hips originating from West Africa, they are traditionally worn by women as a symbol of beauty, sexuality, femininity, fertility, well-being or maturity.
Waist beads was commonly made of glass, metal, crystals, gemstones, charms, wood, or plastics, they are typically strung on cotton thread, twine, wire, cord (elastic or non-elastic). The colors and materials has a symbolic, cultural, or personal significance for the wearer.
The culture or beliefs of the wearer determine when the beads are worn or taken off. Waist beads are commonly used for health tracking, such as weight loss.
Origins
Waist beads actually originated in ancient Egypt, where they were known as girdles. Egyptians wore them around their waist or lower abdomen. Girdles were symbols of status and were made of chains, wire, thread, and shells, and often featured multiple colors Modern-day people from many African cultures wear waist beads, including Ghanaians, Senegalese, Igbos, Yorubas, Ewes, Ashantis, Krobos, Swahilis, bakongoMijikenda and Ga-Adangbes. Each culture has its own reasons for wearing waist beads. In many African cultures, waist beads are commonly given to young women around the time they go through puberty.
Ghanaian culture
In Ghanaian culture, women begin to wear waist beads as they age and on orders from their mothers. Beads are a part of the rite of passage during puberty, which is associated with fertility and marriage. This symbolizes maturity and the beginning of womanhood. The initiation ceremony held for a young woman is called Dipo, during which beads are worn on the neck, ankles, and waist. Waist beads are often worn to represent luck and are commonly made of seeds, seashells, glass pieces, teeth, ivory, and stones. They are often hand-painted. The size of the waist beads is said to signify a woman's level of sexual maturity. In some traditions, waist beads are considered intimate and personal and are not supposed to be seen by anyone except the person's significant other. Today, waist beads are also used as a fashion statement.
Igbo
The use of waist beads in Igbo culture dates back to 500 BC and has been worn by both men and women across all social classes. Waist beads, known as Mgbájí in Igbo language, are commonly used during festivities and traditional ceremonies, and are popular among young girls and married women. They are usually made with materials such as copper, coral, beads, and stones, and held together with string or wire. More than one string is usually worn at a time. Although nowadays waist beads are mostly worn only for traditional Igbo ceremonies such as Igba nkwu (traditional marriage), it is still possible to find these waist beads in the homes of some elderly Igbo women. Traditionally, Mgbájí is one of the essential items a groom must present to his bride, as the bride's wedding attire is incomplete without them. Additionally, the beads were pleasing to watch as the bride danced towards her new husband. Waist beads in Igbo culture symbolize wealth, fertility, and femininity.
Yoruba
The Yoruba people refer to waist beads as Ileke, ibebe idi, Jigida, and Lagidigba. They are both a piece of jewelry and a part of their spirituality. Beads are often made from glass, nuts, wood, or metal and come in varying sizes and colors. In Yoruba culture, waist beads are a part of the rite of passage for young women. As a young woman outgrows her beads, she receives newer ones, which are worn as symbols of confidence, femininity, fertility, and well-being. Waist beads are worn for posture, beauty, weight tracking, protection, growth, sexual desire, and other reasons. In addition, waist beads can represent royalty and social standing, depending on the price and quality of the beads. Women of royalty usually wear more expensive and rare beads to distinguish themselves from others.
Hausa
The Hausa ethnic group the largest tribe in present-day Nigeria. The use of beads on different parts of the body by men, women, the young and the old dates back to hundreds of decades. The Hausa are very aesthetic-minded and tend to wear beads around the ankles, necks, wrists, waist, etc. Waist beads among the Hausa are referred to as Jigida. It is common to see newborn females with beads around their waist. Typical Hausa beads are usually tinier than most, and are made of plastic, wood, bones, cowries and shells. In Hausa culture, there are claims that beads can be used to ward off evil, preserving virginity, and protecting girls from getting raped. They are also worn for adornment, enhancing femininity and sensuality.
Production
Traditionally, when making waist beads, the first step is to define the purpose. The purpose of the beads helps to determine the materials, colors, and sizes of the beads. Next, waist or hip measurements are taken, and the string is cut to size accordingly. Before adding the beads, a clasp is added to the end of the string so that the beads can be easily put on. On the opposite end of the string, chain loops are added to connect the clasp. Then, bead colors and materials are chosen, and the designer can select the pattern that the beads will follow and add them to the string. Lastly, the waist beads are sealed either with a clamp, a tight knot, a crimp lock, or may be burned together firmly. Then, the waist beads are ready for wearing.
Due to their recent popularity, many small businesses and shops now sell waist beads.
Purpose
The purpose and meaning of waist beads are individual to the wearer, but may represent personal beliefs or cultural heritage, often expressed through the choice of colors and materials. In many cultures, the purpose of waist beads is to signify the beginning of womanhood and to represent fertility. Waist beads are often given to a young woman by her mother to mark her transition into womanhood and her sexuality. Each culture's beliefs determine whether the beads are only intended to be seen by the woman's husband or not. In some cultures, there is a belief that waist beads have a sexual aspect to them and can help attract a partner. They are also believed to help develop a woman's curves and slim her waist because they do not stretch.
Uses
Fashion statement: many people today wear waist beads as a piece of body jewelry or an accessory.
Weight control: others use the waist bead to measure their waist size and over time the band will fall or roll up due to weight loss or weight gain.
Culture: there are a variety of meanings for waist beads in different cultures such as maturity and sexual attraction. Cultures that traditionally utilize waist beads include the Egyptian culture, Ghana, Yoruba, Ewe, Ashanti, Krobo, Ga-Adangbe, and others.
Spirituality: those who are practicing the awareness of the spirit use the waist beads for personal performances.
Bibliography
Moroney, Morgan. (2022). "Egyptian Jewelry: A window into Ancient Culture". Johns Hopkins University.
This article explains the ancient Egyptian jewelry based on their culture through the American Research Center in Egypt, therefore the information presented has been thoroughly analyzed and studied.
Yates, Jacqueline. (2022). "Waist beads are the exquisite adornments tied to empowering women, celebrating rich culture". Good Morning America.
This is a very popular news site, so it should be reliable but does not provide any references of in-depth research.
Uju. (2021). "The African Waist Beads – Meaning, Significance And Uses". Answers Africa.
This is a news and entertainment website that conducts in-depth investigation on topics to provide reliable information to the community.
HuyHoa. (2022). "Waist Beads: Everything You Need To Know".
This is where a team of people come together and blog to share their wisdom about many different topic, there is a section that lists the references to provide credible evidence.
Dwell Ghana. (2019). "Ghana's Incredible Bead Culture".
This is a site that assists in relocation people to Ghana that provides knowledge about the Ghana Culture with references provided.
Canva. (2022). "Color meaning and symbolism: How to use the power of color".
Canva explains many colors in depth.
Beadage. (1998–2022). Gemstone Meanings & Crystal Properties.
The website defines the meaning of many different crystals and gemstones.
Gemstone Dictionary. "The meaning of Pink Diamond".
The gemstone dictionary explains what different gemstones mean, I used it for the pink diamond.
References
Culture of Africa
African clothing
Jewellery components
Jewellery
Beadwork
Ancient culture
Waist | Waist beads | [
"Technology"
] | 1,842 | [
"Jewellery components",
"Components"
] |
70,615,665 | https://en.wikipedia.org/wiki/Alexander%20F.%20Wells | Alexander Frank Wells (2 September 1912 – 28 November 1994), or A. F. Wells, was a British chemist and crystallographer. He is known for his work on structural inorganic chemistry, which includes the description and classification of structural motifs, such as the polyhedral coordination environments, in crystals obtained from X-ray crystallography. His work is summarized in a classic reference book, Structural inorganic chemistry, first appeared in 1945 and has since gone through five editions. In addition, his work on crystal structures in terms of nets have been important and inspirational for the field of metal-organic frameworks and related materials.
Education and career
Wells studied at The Queens' College, University of Oxford and obtained his BA and MA in 1934 and 1937, respectively. He then moved to University of Cambridge, where he obtained his PhD in X-ray crystallography in 1939, under the supervision of J. D. Bernal. His PhD thesis was titled The Crystal Structures of Certain Complex Metallic Compounds. He worked as research scientist at Cambridge from 1937 to 1940 and at University of Birmingham from 1940 till 1944. He moved to the industry afterwards, working as a senior research associate at Imperial Chemical Industries from 1944 to 1968. Wells was not interested in senior administrative jobs offer to him in the industry, he moved back to academia and became a professor of chemistry at University of Connecticut in the US from 1968 until his retirement in 1980.
Personal life
Wells is known to his friends and family as Jumbo. He is an accomplished pianist. He married Ada Squires, then a widow, in 1939. During World War II, Wells worked on developing phosphors to be used in cathode-ray tubes and in helping service people move about in the dark.
Bibliography
Paper series
Other selected papers
Books
See also
Periodic graph (crystallography)
Coordination geometry
Michael O'Keeffe (chemist)
List of books about polyhedra
References
British chemists
1912 births
1994 deaths
British crystallographers
University of Connecticut faculty
Alumni of the University of Oxford
Alumni of the University of Cambridge
Imperial Chemical Industries people
Crystallographers
Inorganic chemists
20th-century British chemists | Alexander F. Wells | [
"Chemistry",
"Materials_science"
] | 434 | [
"Crystallography",
"British inorganic chemists",
"Inorganic chemists",
"Crystallographers"
] |
70,615,797 | https://en.wikipedia.org/wiki/SCTbio | SCTbio is global contract development and manufacturing organization (CDMO) providing cGMP services of Advanced Therapy Medicinal Products (ATMPs). It operates in Europe and North America. The company has strong expertise in the development of autologous cell-based products, cell banking and all needle-to-needle GMP operations, including a validated apheresis collection sites network, product manufacturing, QC, GMP storage, QA/QP release, and worldwide drug products supply for clinical and commercial scale.
Founding
SCTbio was founded in 2021 and is a part of the larger PPF Biotech network. SCTbio was initially part of the SOTIO group, providing drug development and manufacturing capabilities. Its CEO, Luděk Sojka, has been part of the PPF Biotech network and SOTIO since 2011.
On July 1, 2021, SOTIO implemented an official split into two sister companies, SCTbio and SOTIO Biotech.
Operations
SCTbio conducts global operations in Europe and in the USA. The cGMP cell manufacturing facility is based in Prague, Czech Republic. The GMP facility features over 2,000 square meters of total space, including 420 square meters of total clean room area (4,520 sq ft). SCTbio offers the ability to of manufacture genetically modified products that require the separation of viral and non-viral components. The physical segregation minimizes any risk of cross-contamination.
Services
CGMP Manufacturing and Quality control: SCTbio provides full production services covering autologous, or allogenic cell and gene therapy products, and in collaboration with sister Cambridge facility recently expanded to the area of viral vectors. SCTbio leads manufacturing processes from various starting materials, including apheresis products, whole blood, and tumor tissues. The company also conducts quality control testing based on a variety of cellular and molecular methods and provides rapid sterility testing.
Analytical Development: SCTbio conducts development, optimization and implementation of analytical methods, including expertise in cellular, flow cytometry, molecular and microbiology-based methods, provided with the development of standard operating procedures, as well as contributing to methods qualification and validation.
Process Development: SCTbio contributes to the design and development of customized manufacturing procedures, in line with cGMP standards to create new working instructions and standard operating procedures, as well as developing technology transfer plans and execution.
Logistics Services & Apheresis Collection: SCTbio has contributed to a number of clinical trials and developed their logistical services while operating under SOTIO. They have a vast network of logistical services that include shipping and validation of apheresis products and provide technical expertise on the harvesting of peripheral blood mononuclear cells.
Procurement & Warehouse Management: SCTbio participates in the procurement of raw materials for product development and adheres to GxP practices. The company has its own storage facility in Prague that provides different controlled temperature from -190° (liquid nitrogen) to room temperature.
Quality and Regulatory Support: SCTbio provides support and services for quality system checks in the European Union, United Kingdom, and United States. They oversee the final drug products in each of these markets and have flexible quality systems that are in line with the territories that they are established, using electronic Quality Systems and Quality Document management systems that implement custom design and monitoring capabilities.
References
Biotechnology
Life sciences industry
Biotechnology companies of the Czech Republic
PPF Group
Biotechnology companies established in 2021 | SCTbio | [
"Biology"
] | 701 | [
"Biotechnology",
"Life sciences industry",
"nan"
] |
70,617,211 | https://en.wikipedia.org/wiki/Cohoke%20Light | The Cohoke Light is a reported ghost light in King William County, Virginia near West Point. The light has been frequently sighted along a stretch of Virginia State Route 632, where Mt. Olive Cohoke Road crosses the Norfolk Southern Railway.
The light typically appears a distance of several hundred yards from the railroad crossing, approaching noiselessly while increasing in brightness. Its presence attracted large numbers of spectators from around the state throughout the 1960s and 1970s hoping to catch a glimpse of the light.
Several paranormal theories have been advanced for the origin of the Cohoke Light. In one legend, a train loaded with wounded Confederate soldiers departed from Richmond after an 1864 battle, intending to evacuate its passengers to West Point, but never arrived. Another story describes the light as the lantern of a railroad worker decapitated in a nineteenth-century train accident as he searches for his missing head. These fanciful legends are likely not based in fact; there are no records of railroad decapitations near West Point, and during the American Civil War Confederate forces in the area retreated away from West Point in the direction of Richmond, the opposite of what was described in the legend. Furthermore, the earliest accounts of the Cohoke Light date to the 1950s, long after the commonly-accepted origin stories.
By 2014, appearances of the Cohoke Light had become extremely rare.
References
External links
– Recollections of the Cohoke Light, collected circa 2001.
Reportedly haunted locations in Virginia
Atmospheric ghost lights
Weather lore
Environment of Virginia
UFO-related phenomena
Unexplained phenomena | Cohoke Light | [
"Physics"
] | 317 | [
"Weather",
"Physical phenomena",
"Weather lore"
] |
70,620,578 | https://en.wikipedia.org/wiki/HD%2020104 | HD 20104 (HR 967) is a visual binary in the northern circumpolar constellation Camelopardalis. The system has a combined apparent magnitude of 6.41, making it near naked eye visibility. When resolved in a large telescope, HD 20104 appears to be a pair of 7th magnitude A-type main-sequence stars with a separation of about . Located approximately 550 light years away, the system is approaching the Sun with a heliocentric radial velocity of .
The system's stars have masses twice that of the Sun and effective temperatures ranging from 8,100 to 8,700 K, typical of stars their type. The primary radiates at − over luminous for its class − and spins with a projected rotational velocity of . HD 20104 has an age of 313 million years.
References
Camelopardalis
A-type main-sequence stars
Binary stars
020104
0967
BD+65 388
015309 | HD 20104 | [
"Astronomy"
] | 195 | [
"Camelopardalis",
"Constellations"
] |
70,620,666 | https://en.wikipedia.org/wiki/Waxman-Bahcall%20bound | The Waxman-Bahcall bound is a computed upper limit on the observed flux of high energy neutrinos based on the observed flux of high energy cosmic rays. Since the highest energy neutrinos are produced from interactions of utlra-high-energy cosmic rays, the observed rate of production of the latter places a limit on the former. It is named for John Bahcall and Eli Waxman.
Cosmic rays
The Waxman-Bahcall limit comes from the analysis of cosmic rays at various energy levels and their respective fluxes. Cosmic rays are high energy particles, like protons or atomic nuclei that move at near the speed of light. These rays can come from a variety of sources such as the Sun, the Solar System, the Milky Way galaxy, or even further beyond.
Upon entry into our atmosphere, these cosmic rays interact with atoms in the atmosphere, initiating cosmic-ray air showers. These showers are cascades of secondary particles, including muons and neutrinos. These atmospheric neutrinos can be studied and a general plot of the energy of said neutrinos and their fluxes can be determined and created. The plot below shows the cosmic-ray energy spectrum. Caution: the energy spectrum of atmospheric neutrinos is different; also, the Waxman-Bahcall bound does not apply to atmospheric neutrinos, but to (ultra)-high-energy neutrinos from outside of our galaxy.
During Waxman's and Bahcall's research and work into neutrinos, there seemed to be a gap of very high energetic neutrinos, past the atmospheric neutrino limit, but still below the GZK limit, meaning there exists some extra-galactic high energy neutrino source yet to be detected.
Atmospheric neutrinos
Atmospheric neutrinos are produced in the atmosphere, about 15 km above the Earth's surface. They are the result of particles, usually protons or light atomic nuclei, hitting other particles in the atmosphere and causing a shower or neutrinos into the Earths surface.
Atmospheric neutrinos were successfully detected in the 1960s when experiments were able to successfully find muons that resulted from these neutrinos. From that, they were able to find the energy of the neutrinos and the flux associated with them. Currently, neutrinos are able to be detected by many different experiments, such as IceCube Lab, allowing for the higher accurate measurements of their energy and fluxes.
GZK limit
The GZK limit exists as a limit on the highest possible cosmic-ray energy that can travel without interaction through the universe, and cosmic rays above around 5 x 1019 eV can reach Earth only from the nearby universe. The limit exists because at these higher energies, and at travel distances further than 50 Mpc, interactions of cosmic rays with the CMB photons increase. With these interactions, the new cosmic-ray product particles have lower and lower energy, and cosmic rays above a few 1020 eV do not reach Earth (except if their source would be very close). Important in this context is that the GZK interactions also produce neutrinos, called cosmogenic neutrinos. Their energy is typically one order of magnitude below the energy per nucleon of the cosmic ray particle (e.g., a 1020 eV proton would lead to 1019 eV neutrinos, but a 1020 eV iron nucleus with 56 nucleons, would lead to neutrions of 56 times lower energy than for the proton case).
Waxman - Bahcall upper bound
The Waxman - Bahcall upper bound is derived from a problem where neutrinos were discovered to have a higher energy than the atmospheric limit but still below the GZK limit discussed above. Unsure about what possible source could be the cause of these neutrinos, Waxman and Bahcall worked to cross off possible other sources, such as assist from magnetic fields, redshift correction, and sources of high energy outside the Milky Way Galaxy.
The current upper bound on the intensity of muon neutrino is said to be:
with the expected neutrino intensity to be 1/2 Imax.
Redshift losses
Initially in the derivation for the muon neutrino intensity above, redshift factors were ignored. However, if a correction factor was included, it could also be found that the neutrinos detected above either started out at high energies and were detected at a lower energy due to redshift.
It is known, however, that if red-shift is to be the prime factor in the limit, that the proton would have had to have a redshift z of less than 1. If the particle started from outside this range, as told by the GZK limit, other interactions would take place during the particles travel, and make it so that the neutrinos detected would be far below the threshold discussed.
Deriving a correction factor to multiply by Imax to change the threshold of the system, it was found to be:
Working with nearby galaxies and clusters, it was found that there is no significant change on the limit from the redshift correction, and that the reason for the limit and expected values outside of the limit has to come from some other external source.
Magnetic fields
Neutrino Source
Another factor to consider was the addition of the magnetic fields at the source of the neutrinos and how it might allow for increased energy of an incoming charged particle from a cosmic ray. If protons can be prevented from leaving the source due to a magnetic field, then only neutrinos would be allowed to go through, meaning we would be able to see higher level neutrinos. Bahcall and Waxman quickly ruled this out as a permanent option, as when there is a proto-meso interaction a charged pion is created but a proton is then also turned into a neutron. The neutron will not be affected by the field in any way, and will travel about 100 kpc when with high energies. This makes it impossible to exceed the upper bound found earlier from Waxman and Bahcall.
Intergalactic magnetic field
Another theory is that the intergalactic magnetic field would be able to change the direction of the protons on their way to Earth, allowing for the neutrinos to come in relatively in a straight line.
To derive this theory, Waxman and Bahcall started with the basic proton traveling with energy E, in a magnetic field B, and with correlation length λ. If the proton travels a distance of λ, the resulting angle of deflection is:
Where Rl is the Larmor Radius.
If the angle is kept small, and propagating a distance l, the new deflection angle becomes:
Plugging in values for time, which would give us a maximum propagation distance that the particle could travel in that time, we find that the existence of a uniformly distributed inter-galactic magnetic field would have no effect on the limit.
Possible causes
Active galactic nuclei jet models
When looking out into the galaxy, and starting to think about what could have caused such high energy neutrinos to appear, it was thought of that jets from Active Galactic Nuclei (AGN) were the main cause. Looking further into the details, Waxman and Bachall saw that the intensities for jets from AGN's are two times higher in magnitude than the limit discussed above.
Initially, it was thought that the photons and protons were accelerated into the jets thanks to Fermi acceleration with an energy spectrum:
for both protons and photons (simply plug in the values for photons or protons for either quantity). This implies the optical depth is related to Ep and assuming a small optical depth allows us to have the neutrino spectrum of:
Later, it was realized that the decay of neutral pions, which are created along with charged pions, cause a high energy gamma ray emission. It was then found that the large energies being seen was not a result of Compton scattering of protons and photon, but of neutral pion decay. Once this emission was fixed, the intensity of the neutrinos found from AGN was under the max limit discussed above, and AGN then became a valid cause for these higher energy neutrinos if the area was optically thin and the energy burst was cause by a single interaction of a decaying neutral pion.
Gamma ray bursts
The Gamma-Ray Bursts (GRB) fireball model has also been another candidate for the reasoning behind higher energy neutrinos.
The high energy neutrino model already took multiple variables into account and was a match for the limit discussed above. Similar to AGN's, the GRB's are optically thin, however, unlike AGN's which needed some more assumptions to be made on how the energy was being expelled and reached to match the flux calculations, the GRB model was able to correctly match this limit.
The fireball model works by having the initial burst of the GRB, but then has another shock later on which goes onto explain the afterglow associated with GRB's. This second shock continues to push particles away and allows them to reach detectors on Earth within the limits discussed earlier.
Bibliography
Alemany, R.; Burrage, C.; et al. "(2019). Summary Report of Physics Beyond Colliders at CERN".
Gives a sense of the colliders at CERN that can help with this data set
Bradascio, F.. (2019). "Search for high-energy neutrinos from AGN cores". Proceedings of Science.
Another peer reviewed article, this source allows for further information into parts of AGN that is included in the initial article.
Kachelriess, M.. (2022). "Extragalactic cosmic rays". FOS: Physical Science
A journal reviewed article describing extra-galactic cosmic rays
Kachelriess, M.; Semikoz, D.V. (2019). "Cosmic ray models". Progress in Particle and Nuclear Physics, 109, 103710.
Peer reviewed journal that gives a broad understanding of cosmic ray models and different experiments
Kajita T. Atmospheric neutrinos and discovery of neutrino oscillations. Proc Jpn Acad Ser B Phys Biol Sci.
Gives information about neutrinos - journal reviewed document
Kimura, S.. (2022). "Neutrinos from Gamma-ray Bursts". FOS: Physical Sciences.
The peer reviewed journal article above works to give a further insight in to high energy neutrinos from GRB's, which is discussed in the original article by Bahcall and Waxman and gives a further insight into the paper
Letessier-Selvon, A. (2001). "Establishing the GZK cutoff with ultra high energy tau neutrinos". AIP Conference Proceedings.
This is a peer reviewed source, and it works to add details about other factors and components necessary for our analysis
Piran, T. (1999). Gamma-ray bursts and the fireball model. Physics Reports, 314(6), 575–667.
journal reviewed article that gives a brief insight into how the fireball method works.
Kronberg, P. (2003). "Intergalactic Magnetic Fields". Physics Today, 55
The journal reviewed article above gives more information on the intergalactic magnetic fields mentioned above in the paper
Waxman, E; Bahcall, J (1998). "High energy neutrinos from astrophysical sources: An upper bound". Physical Review D, 59(2).
This paper is a peer reviewed paper made by the authors Waxman and Bachall and gives a good overview of the overall topic chosen
References
Neutrinos
Physical quantities
Cosmic rays | Waxman-Bahcall bound | [
"Physics",
"Mathematics"
] | 2,467 | [
"Physical phenomena",
"Physical quantities",
"Quantity",
"Astrophysics",
"Radiation",
"Physical properties",
"Cosmic rays"
] |
70,620,703 | https://en.wikipedia.org/wiki/ACS%20Applied%20Energy%20Materials | ACS Applied Energy Materials is a monthly peer-reviewed scientific journal that was established in 2018 by the American Chemical Society. It covers aspects of materials, engineering, chemistry, physics, and biology relevant to sustainable applications in energy conversion and storage. The editor in chief is Kirk S. Schanze. According to the Journal Citation Reports, the journal has a 2022 impact factor of 6.4.
Scope
ACS Applied Energy Materials publishes letters, articles, reviews, spotlight on application, forum articles, and comments across a given subject area. Specific materials of interest will include, but are not limited to:
Fuel cell
Supercapacitor
Thermoelectrics
Photovoltaics
Photo-electrosynthesis cells
See also
ACS Applied Materials & Interfaces
References
External links
Applied Energy Materials
Academic journals established in 2018
Monthly journals
English-language journals
Materials science journals | ACS Applied Energy Materials | [
"Materials_science",
"Engineering"
] | 174 | [
"Materials science journals",
"Materials science"
] |
70,621,516 | https://en.wikipedia.org/wiki/Cytokine%20delivery%20systems | Cytokines are polypeptides or glycoproteins that help immune cells communicate to each other to induce proliferation, activation, differentiation, and inflammatory or anti-inflammatory signals in various cell types. Studies utilizing cytokines for antitumor therapies has increased significantly since 2000, and different cytokines provide unique antitumor activities. Cytokines hinder tumor cell development mostly through antiproliferative or proapoptotic pathways but can also interrupt development indirectly by eliciting immune cells to have cytotoxic effects against tumor cells. Even though there are FDA-approved cytokine therapies, there are two main challenges associated with cytokine delivery. The first is that cytokines have a short half-life, so frequent administration of high doses is required for therapeutic effect. The second is that systemic toxicity could occur if the cytokines delivered cause an intense immune response, known as a cytokine storm.
Pegylated cytokines
Pegylation is the process of covalently binding polyethylene glycol (PEG) to proteins. Pegylation prolongs the half-life of the bound protein, leading to sustained delivery. This is advantageous because lower, less frequent dosing will be needed to have the same therapeutic effect in the patient, which will limit the cytotoxicity of the delivery system. Pegfilgrastim is a successful example of this delivery system. Pegfilgrastim is the pegylated form of the granulocyte-colony stimulating factor (G-CSF) filgrastim. Pegfilgrastim stimulates production and release of neutrophils in patients who experience bone marrow toxicity after receiving myelosuppressive anticancer drugs or radiation. Filgrastim has a half-life of 3-4 h, while Pegfilgrastim has a half-life of 45 h. This is much more convenient for patients, as they will only need one dose of Pegfilgrastim instead of multiple doses of Filgrastim drawn out over a long period. Ciliary neurotrophic factor (CNTF) is a cytokine used to combat diabetes symptoms such as appetite reduction and weight loss. A pegylated version of CNTF retained biological activity in vitro and had enhanced pharmacokinetics. The pegylated CNTF also reduced glycemia in diet-induced obese animals, with a dose 10-fold higher than unmodified CNTF. These studies demonstrate that pegylated cytokines can be used for sustained delivery of cytokines, increasing the therapeutic window of these treatments.
A major problem caused by pegylation is that the cytokine may change its molecular conformation, activity, and bioavailability upon PEG binding. Cytokines are advantageous due to their small sizes, which allow them to reach intracellular targets. PEG binding to cytokines could cause them to become too bulky to reach their specific targets, which should be taken into consideration when designing pegylated cytokines.
GAG-based biomaterials
Glycosaminoglycans (GAGs) are naturally derived polysaccharides with distinct sequences of disaccharides. GAGs bind to cytokines and regulate cell recruitment, inflammation, and tissue remodeling by delivering cytokines to the extracellular matrix. Binding studies suggest GAGs have a natural affinity for cytokines, and cytokine binding to GAGs is mediated by nonspecific electrostatic interactions between positively charged domains on cytokines and negatively charged sulfate and carboxylic acid residues on GAGs. The GAG heparin has been explored extensively for cytokine delivery. Heparin-based hydrogels have shown to provide sustained delivery of IL-4 for more than 2 weeks, leading to a greater anti-inflammatory response than IL-4 alone. Another study utilized a starPEG-heparin hydrogel system to deliver vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF-2). The large concentration of heparin allowed loading and release of the cytokines to be independent of each other. The codelivery of the cytokines from the hydrogels led to pro-angiogenic effects both in vitro and in vivo, with the effect being much greater than administration of the single growth factors
Immunocytokines
Antibody conjugation is another promising method for cytokine delivery. Antibody conjugation to cytokines can be used to improve site-specific delivery and prolong the cytokine half-life. Immunocytokines are delivered systemically but can specifically target the tumor through overexpressed or unique tumor antigens, cryptic extracellular matrix epitopes found only in tumors, or neovasculature markers indicating tumor angiogenesis. Cergutuzumab amunaleukin (CEA-IL2v) is an antibody-cytokine conjugate that links the cytokine IL-2 with an antibody targeting the carcinoembryonic antigen (CEA). This conjugate preferentially targets the tumor microenvironment to increase local delivery of IL-2 and minimize off-target toxicity. CEA-IL2v is ongoing phase I clinical trials in treating solid malignancies expressing CEA. Another immunocytokine is huBC1-IL12, which was developed to target the ED-B domain of fibronectin. This domain is overexpressed in tumor tissues but undetectable in almost all normal adult tissues. Systemic administration of huBC1-IL12 eliminated experimental PC3 metastases and suppressed the growth of multiple human tumor lines in immunocompromised mice more effectively than IL-12 alone. A Phase I trial studied the safety of weekly infusions of huBC1-IL12 in renal carcinoma and malignant melanoma patients. The maximum tolerated dose was found to be 15 ug/kg, which is 30 times higher than the maximum tolerated dose of IL-12 alone
Systemically administered immunocytokines are likely to significantly reduce cytokine-related cytotoxicity, but not eliminate it. Immunocytokines still interact with immune cells to induce signaling outside of the tumor, and there are problems with non-specific binding in non-target tissues that could disrupt regular immune functions in the body. Since immunocytokines are foreign to the body, they could also cause an immune reaction that produces anti-immunocytokine antibodies leading to pharmacological abrogation, therapeutic alteration, or hypersensitivity reactions.
Nonviral nanoparticles
Nanoparticle delivery systems are popular due to their ability to encapsulate compounds without affecting bioactivity, and they exhibit controlled and sustained release of the encapsulated compounds to target tissues. Nanoparticles can be made of organic or inorganic agents and possess the ability to stabilize cytokines in vivo, enhance activity at the target site, improve aqueous solubility, and reduce systemic toxicity. Solvent, pH, temperature, charge, and size are many parameters that influence the encapsulation efficiency, nanoparticle toxicity, and cytokine stability. Cytokines can be encapsulated, adsorbed, or conjugated into nanoparticle systems for their delivery, and there are multiple nanoparticle systems that can be utilized for cytokine delivery
Polymeric nanoparticles are biocompatible, have low toxicity, and are biodegradable. They can be used to improve circulation times, stability, and encapsulation capacity compared to other nanoparticle systems. Polylactic-co-glycolic acid (PLGA) is the most popular polymer for nanoparticle delivery systems due to its simple synthesis using the oil-in-water method, high stability, easy encapsulation or adsorption of both hydrophobic and hydrophilic molecules, and easy surface modification. PLGA-PEG nanoparticles encapsulating IL-10 were created to prevent plaque formation in advanced atherosclerosis lesions. PLGA was charged at its terminal portions for better electrostatic interaction with IL-10 while PEG was used to functionalize the nanoparticle. These PLGA-PEG-IL-10 nanoparticles allowed for greater stability and prolonged systemic circulation of IL-10 and did not show any in vitro or in vivo cytotoxicity.
Liposomes are another type of nanoparticle delivery system widely studied. Liposomes can easily cross lipid bilayers and cell membranes but usually get rapidly eliminated in vivo unless stabilized with PEG or another polymer. Formation of liposomes can also present issues, as toxic solvents, high temperatures, and low pH can decrease the biosafety of the nanoparticles or denature the cytokine being delivered. Conjugating cytokines to liposomal surfaces is a useful approach because it allows cytokines to bind to their respective target cell receptors and allows multiple drugs to be delivered to potentiate the desired effect. Conjugating cytokines to the surface of lipids is typically done using the layer-by-layer technique which involves layering polymer materials to create a thin film that can regulate material properties of the carrier. Advantages of this nanoparticle design include multiple drug compartments for sequential cargo release, the ability to tailor surface chemistry with polymer layers to affect targeting and biodistribution, and improved pharmacokinetics. Rationally engineered layer-by-layer nanoparticles demonstrated high loading and release of active IL-12, localization of nanoparticles on the surface of tumor cells allowing IL-12 to be available to membrane receptors, and decreased systemic exposure. These layer-by-layer lipid nanoparticles significantly reduced IL-12 toxicity and demonstrated antitumor activity against colorectal and ovarian tumors at doses that were not tolerated with free IL-12 delivery
Gold nanoparticles are becoming increasingly popular as they exhibit high surface-to-volume ratio, they can easily travel to target cells, and they support high drug load. They can also easily be functionalized and synthesized. Gold-bound tumor necrosis factor (TNF) is in phase I trials for treatment of solid tumors. The trial found that gold-bound TNF has a tolerable dose that is three times higher than the tolerable dose for unmodified TNF. There was also higher drug concentration in the tumor tissue, indicating increased local delivery to the tumor microenvironment. Gold nanoparticles can elicit an immune response that hinders their efficacy, so it is important to evaluate cellular response such as cytokine production and reactive oxygen species production
Silica nanoparticles have also been evaluated for cytokine delivery due to their high colloidal stability, extensive surface functionalization, and possibility to control both structure and pore size. However, silica nanoparticles present limitations for cytokine delivery due to the low internalization efficiency for larger biomolecules. This challenge can be overcome by developing mesoporous silica nanoparticles with extra-large pores. These nanoparticles were used to deliver IL-4 to induce M2 macrophage polarization for anti-inflammatory and tissue homeostasis therapies. These nanoparticles increased IL-4 half-life, showed minimal toxicity, efficiently loaded and delivered IL-4, and stimulated M2 macrophage polarization
Plasmid nanoparticles
Nucleic acids are much easier to produce, purify, and manipulate than recombinant cytokines and offer a method to deliver them locally and sustainably. Plasmid nanoparticles expressing cytokines coupled with electroporation is currently being explored for cytokine delivery. Electroporation temporarily increases the permeability of cell membranes without damaging the membrane structure. IL-12 is a cytokine known to have antitumor properties but shows severe dose-related toxicities in many patients. Intratumoral delivery of a plasmid encoding IL-12 followed by electroporation in a murine melanoma model resulted in a 47% cure rate. A phase II trial examined the safety and activity of plasmid encoding IL-12 followed by electroporation to treat stage III/IV unresectable melanoma. The median survival was 3.7 months with an objective overall response rate of 29.8%, including two complete responses. There were no grade IV events reported, and adverse events were rare
Other DNA complexes being evaluated to enhance cytokine delivery include lipoplexes, polyplexes, and lipopolyplexes, which are complexes of lipids, polymers, and lipids with polymers, respectively. Polyehtyleneimine (PEI) is a highly cationic polymer that complexes with negatively charged DNA. PEI protects DNA from degradation in vivo, promotes interaction with negatively charged cell membranes, and enhances release from lysosomes by acting as a proton sponge. PEI:IL-12 complexes were shown to transfect lung tissue following delivery via nebulization, leading to production of IL-12 in the lungs. Weekly or twice weekly administration of PEI:IL-12 was found to suppress or eliminate pulmonary metastases of SAOS-2 human osteosarcomas in athymic nude mice. In a different study, nanoparticles were created with a liposomal shell and two DNA encoding complementary sequences as the core. The liposomal shell was designed to be degraded by phospholipase A2 (PLA2), which is overexpressed by various tumors. The cytokine TRAIL was loaded onto the Ni2+ modified DNA cores. Upon interaction with PLA2, the DNA nanoparticles transformed into nanofibers to deliver TRAIL to death receptors on the cancer cell membrane. Delivery of TRAIL amplified apoptotic signaling with reduced TRAIL internalization to enhance antitumor efficacy
Viral systems
Oncolytic viruses preferentially infect malignant cells, inducing immunogenic cell death. Oncolytic viruses include adenoviruses, Herpes simplex viruses, Semliki forest viruses, poxviruses, among others. They can be altered to optimize distribution and facilitate delivery to target tissues. Cytokine-loaded oncolytic viruses have shown activity in murine models, with several clinical trials under investigation. IMLYGIC (talimogene laherparepvec) was the first FDA-approved oncolytic virus for cancer treatment. It is a modified herpes simplex virus-1 expressing granulocyte-macrophage colony-stimulating factor (GM-CSF) for recurrent melanoma. It is currently being studied for soft-tissue sarcoma and liver cancer and for combination with immunotherapies. Adenoviruses are widely studied for cytokine delivery. In preclinical trials, intratumoral injections of adenoviruses encoding IL-12 (Ad-IL-12) mediated regression of murine colorectal carcinomas, breast carcinomas, prostate carcinomas, gliomas, bladder carcinomas, fibrosarcomas, laryngeal squamous cell carcinoma, hepatomas and hepatocellular carcinomas, medullary thyroid carcinomas, thyroid follicular cancer, and Ewing's sarcoma. The antitumor immune response of Ad-IL-12 is primarily mediated by CD8+ T cells.
There are many limitations associated with virus-based delivery systems. Anti-viral antibodies could be produced against viral cytokine delivery systems leading to delayed-type hypersensitivity responses, which may prevent repeated dosing. There is also a large disparity in the susceptibility patients have to viral infections since viral delivery of cytokines requires transfection of host cells, which is highly variable from patient to patient. There has also been significant off-target transgene expression seen in clinical trials. Small volumes of intratumoral injection of adenoviruses were shown to cause significant transgene expression in the liver, intestine, spleen, kidney, and brain.
Activity-on-Target Cytokines
Activity-on-Target Cytokines, known as AcTakines, are mutated cytokines that have reduced binding affinity for their native receptor complex and enhanced binding affinity for a specific tumor cell receptor. This causes the cytokine to be inactive in circulation, limiting systemic toxicity. The cytokine is activated upon binding to its tumor-specific antigen, allowing for local delivery. The cytokine tumor necrosis factor (TNF) causes rapid hemorrhagic tumor necrosis in both animal models and patients but is associated with high systemic toxicities. TNF is known to exert its antitumor effect through stromal cells in the tumor microenvironment. A TNF AcTakine was created to improve localized delivery of TNF and decrease systemic toxicity by changing its antitumor pathway to target endothelial cells. This mutated TNF cytokine was shown to only target endothelial cells of the tumor vasculature, allowing for a safe and effective delivery system. This TNF-based AcTakine resulted in a 100-fold increase in targeting efficiency, and when the AcTakine was targeted to CD13 expressed on endothelial cells of the tumor vasculature, it demonstrated selective activation of tumor neovasculature without any detectable toxicity in vivo. When administered with CAR-T cells, this therapy was shown to enhance T cell infiltration to control solid tumors, while combination with a CD8-targeted type II interferon AcTakine led to eradication of solid tumors
Cytokine factories
Cytokine factories are cell-generated cytokines that can locally deliver a cytokine of interest, offering spatial and temporal control of dosing. The homing capacity and tumor tropism capabilities of mesenchymal stem/stromal cells (MSCs) make them ideal drug delivery vehicles. MSCs also have reduced immunogenicity due to their limited expression of costimulatory molecules. Using MSCs to express cytokines provides greater cytokine delivery to the tumor tissue, which increases therapeutic efficacy of the treatment. IL-2 gene engineered MSCs (MSC-IL-2) have been studied as a potential antitumor therapy since IL-2 is an immunogenic cytokine. Intratumoral injection of MSC-IL-2 was shown to significantly regress glioma tumor growth and improve the overall survival of rats with glioma. Similarly, subcutaneous injections of bone marrow MSC-IFN-α affected tumor growth in vivo and increased overall survival in a multiple myeloma mouse model. Antitumor effects were attributed to increased apoptosis of tumor cells, decreased microvessel density, and ischemic necrosis. TRAIL is an immunogenic cytokine that selectively targets tumor cells for apoptosis, reducing systemic toxicity. MSCs engineered to overexpress TRAIL have shown promising antitumor effects in xenograft models through apoptotic pathways. Numerous studies of MSC-TRAIL systems are ongoing, including treatments for neuroblastoma, non-small-cell lung carcinoma, breast cancer, pancreatic cancer, glioblastoma, and multiple myeloma, among others
Human retinal pigmented epithelial (RPE) cells can also be engineered to express a cytokine of interest. RPE cells are ideal cytokine delivery systems because they are nontumorigenic, display contact inhibition, are amenable to genetic modification, have bene previously used in human trials for therapeutic delivery systems, and are safe to use. RPE cells engineered to produce different cytokines were encapsulated in alginate-based microparticles. The encapsulated cells will still viable after encapsulation, did not divide within the capsules, produced the cytokine of interest, and persisted longer in vivo than unencapsulated cells. The IL-2 producing RPE cells eradicated peritoneal tumors in ovarian and colorectal mouse models, and computational modeling of pharmacokinetics, predicts clinical translation to humans, indicating potential success in future human clinical trials
References
Cytokines
Immunotherapy | Cytokine delivery systems | [
"Chemistry"
] | 4,313 | [
"Cytokines",
"Signal transduction"
] |
70,621,532 | https://en.wikipedia.org/wiki/Underground%20World%20Home | The Underground World Home was an exhibit at the 1964 New York World's Fair of a partially underground house which doubled as a bomb shelter. Designed by architect Jay Swayze, who made a specialty of underground homes, it was situated on the campus of the expo besides the Hall of Science and north of the expo's heliport in Flushing Meadows–Corona Park in Queens.
History
The home/bomb shelter was designed by architect Jay Swayze. Swayze, a proponent of underground living, constructed and lived in his own underground bunker-house in Plainview, Texas, which he named Atomitat.
Built during the Cold War only two years after the Cuban Missile Crisis, it was the promotion of the company "Underground World Homes", which was owned by Avon investor and millionaire Girard B. Henderson, who remained convinced that tensions between the U.S. and the U.S.S.R. would escalate eventually escalate to WWIII. (In addition to the prototypical underground home/bomb shelter, there was companion chthonic exhibit sponsored by Henderson: "Why Live Underground?") The brochure for the Underground World Home touted its comfort, luxury, interior design and safety. However, the $1.00 for adults and 50¢ on top of the expo's fee entry, plus the expo's numerous, much more glamorous exhibits, deterred many potential tourists. A May 1964 LIFE magazine cover story on the exposition did not so much as mention the Underground World Home.
Exhibits were contractually required to be dismantled and removed after the fair. Swayze eventually wrote a book, Underground Gardens & Homes: The Best of Two Worlds, Above and Below, but the building's fate was not mentioned. The New York Public Library held archives on the expo, however, and in 2017 it was found that the demolition of the home had been completed on March 15, 1966. Only its foundations, if anything, remain.
Design
The ten-room home featured backlit murals to create the illusion of outdoor space and preclude claustrophobia. The murals were painted by Texas-based artist Mrs. Glenn Smith. Swayze cited research to convince fairgoers that people did not look out their windows 80% of the time, and that and when people did look out their windows, half the time what they saw was undesirable. He stated that he could give people better views with selected murals. The home was touted as peeping Tom proof, less expensive than normal homes, (sic), secure from intruders, and a way to save space above ground.
The home was . The walls were of steel and concrete, and the roof supported by steel beams rated for a load of of soil (which provided the insulation). There were three bedrooms; the ceilings were of gypsum. There was a "snorkel-like system" for air conditioning— an apparatus which purportedly enabled the home to be dusted monthly.
The foyer was , the kitchen/dining room , the living room (with a television set and a wood-burning fireplace) , and three bedrooms of , , and , respectively, connected by a hallway wide . The model home also had a terrace area simulating outdoor space next to the living room of .
Reception
In a 1964 New York Times piece science fiction author Isaac Asimov speculated what the 2014 World's Fair would look like. He deemed the Underground World Home a "sign of the future" with controlled temperatures which allowed occupants to live free from the weather. The home was not a draw, however, and was scarcely to appear in popular memory. Priced at $80,000 (approximately four times the cost of an average home that year), none were commissioned.
Popular culture
The LP record The Best of the Johnny Mann Singers: Underground at the Fair played in background of the exhibit; it did not sell well. This was its only appearance in pop culture (save in the niche mythos of urban exploration, and as one of the oddities of architecture) until its interior was reproduced in the 2009 CSI: NY episode Manhattanhenge as the anachronistic lair of a mad killer, the structure supposedly simply having had soil layered on top of it and been abandoned. The set was complex and impressive.
See also
1964 New York World's Fair pavilions
References
External links
Underground Dream World
Underground World Home Brochure
1964 introductions
1964 New York World's Fair
Air raid shelters in the United States
Cold War sites
Nuclear fallout
Radiation protection
Survivalism
Flushing Meadows–Corona Park | Underground World Home | [
"Chemistry",
"Technology"
] | 927 | [
"Nuclear fallout",
"Environmental impact of nuclear power",
"Radioactive contamination"
] |
70,621,608 | https://en.wikipedia.org/wiki/Joeri%20Rogelj | Joeri Rogelj (born 1980) is a Belgian climate scientist working on solutions to climate change. He explores how societies can transform towards sustainable futures. He is a Professor in Climate Science and Policy at the Centre for Environmental Policy (CEP) and Director of Research at the Grantham Institute – Climate Change and Environment, both at Imperial College London. He is also affiliated with the International Institute for Applied Systems Analysis. He is an author of several climate reports by the Intergovernmental Panel on Climate Change (IPCC) and the United Nations Environment Programme (UNEP), and a member of the European Scientific Advisory Board for Climate Change.
Education
Rogelj completed an engineering degree at the KU Leuven (Belgium) in 2003, and also obtained a postgraduate degree in Cultures and Development Studies at the same institution in 2005. He completed his PhD in climate physics at Swiss Federal Institute for Technology (ETH Zurich) in 2013 under the supervision of Prof. Reto Knutti on the topic of uncertainties in low greenhouse gas emissions scenarios.
Career
Rogelj started his climate science career in the PRIMAP Research Group at the Potsdam Institute for Climate Impact Research (PIK) in 2009. After obtaining his PhD, he joined the International Institute for Applied Systems Analysis. In 2018, he joined the Grantham Institute – Climate Change and Environment at Imperial College London.
From 2006 to 2008, Rogelj worked as a project engineer on rural development projects in Rwanda.
Research and impact
Rogelj publishes on international climate agreements such as the Copenhagen Accord or the Paris Agreement, carbon budgets, emission pathways that limit global warming to 1.5°C and 2°C, net zero emissions targets, and linkages between climate, sustainable development, and justice.
According to the International Science Council, he has pioneered "work on climate change scenarios [that] changed the global conversation around the feasibility of keeping global warming to 1.5°C in advance of the UN Paris Agreement" in 2015.
He serves as a lead author on the annual Emissions Gap Reports from the United Nations Environment Programme (UNEP) that provide annual updates on the gap between country pledges and emission reductions necessary to meet the goals of the Paris Agreement.
He was a contributing author to the 2013-2014 Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), a coordinating author of the 2018 IPCC Special Report on Global Warming of 1.5°C, and a lead author on the 2021 IPCC Sixth Assessment Report.
In 2019, he served as a member of the Climate Science Advisory Group to the United Nations Secretary-General's Climate Action Summit.
Since 2022, he serves on the "European Scientific Advisory Board on Climate Change" that provides independent scientific advice on EU measures, climate targets and indicative greenhouse gas budgets.
Rogelj also provides scientific evidence for climate change litigation, for example, in support of "Children vs Climate Crisis" in which 16 children from across the world petition the UN Committee on the Rights of the Child to hold five of the world's leading economic powers accountable for inaction on the climate crisis.
Awards and honours
Rogelj received the 2021 Early Career Scientist Award for Europe from the International Science Council (ISC) for the "exceptional impact" his research has had on international climate policy. In 2016, he received the inaugural Piers Sellers Award for "world leading solution-focused climate research" by the Priestley International Centre for Climate. In 2014, he received the ETH Medal for his outstanding PhD thesis and in 2010 the Peccei Award for outstanding work by a young scientist.
Rogelj is a Clarivate Web of Science Highly Cited Researcher in 2019 and 2020, recognizing the world's most influential researchers of the past decade, and was ranked 31st in The Reuters Hot List of the World's Top Climate Scientists.
Selected works
Rogelj, J., Geden, O., Cowie, A., Reisinger, A., 2021. Three ways to improve net-zero emissions targets. Nature 591, 365–368. https://doi.org/10.1038/d41586-021-00662-3
Rogelj, J., et al, 2018. Scenarios towards limiting global mean temperature increase below 1.5 °C. Nature Clim. Change 8, 325–332. https://doi.org/10.1038/s41558-018-0091-3
Rogelj, J., et al, 2016. Paris Agreement climate proposals need a boost to keep warming well below 2 °C. Nature 534, 631–639. https://doi.org/10.1038/nature18307
Rogelj, J., et al, 2015. Zero emission targets as long-term global goals for climate protection. Environmental Research Letters 10, 105007. https://doi.org/10.1088/1748-9326/10/10/105007
Rogelj, J., et al, 2015. Energy system transformations for limiting end-of-century warming to below 1.5 °C. Nature Clim. Change 5, 519–527. https://doi.org/10.1038/nclimate2572
Rogelj, J., Meinshausen, M., Knutti, R., 2012. Global warming under old and new scenarios using IPCC climate sensitivity range estimates. Nature Clim. Change 2, 248–253. https://doi.org/10.1038/nclimate1385
Rogelj, J., et al, 2010. Copenhagen Accord pledges are paltry. Nature 464, 1126–1128. https://doi.org/10.1038/4641126a
Rogelj, J., Shindell, D., Jiang, K., Fifita, S., Forster, P., Ginzburg, V., Handa, C., Kheshgi, H., Kobayashi, S., Kriegler, E., Mundaca, L., Séférian, R., Vilariño, M.V., 2018. Mitigation pathways compatible with 1.5 °C in the context of sustainable development, in: Flato, G., Fuglestvedt, J., Mrabet, R., Schaeffer, R. (Eds.), Global Warming of 1.5 °C: An IPCC Special Report on the Impacts of Global Warming of 1.5 °C above Pre-Industrial Levels and Related Global Greenhouse Gas Emission Pathways, in the Context of Strengthening the Global Response to the Threat of Climate Change, Sustainable Development, and Efforts to Eradicate Poverty. IPCC/WMO, Geneva, Switzerland, pp. 93–174. https://www.ipcc.ch/sr15/
References
1980 births
Living people
Belgian climatologists
KU Leuven alumni
Belgian expatriates in Austria
Belgian expatriates in Switzerland
Belgian expatriates in the United Kingdom
ETH Zurich alumni
Academics of Imperial College London
Intergovernmental Panel on Climate Change lead authors
Climate change mitigation researchers | Joeri Rogelj | [
"Engineering"
] | 1,501 | [
"Geoengineering",
"Climate change mitigation researchers"
] |
70,621,892 | https://en.wikipedia.org/wiki/Nathaniel%20Code | Nathaniel Robert Code Jr. (born March 12, 1956) is an American serial killer and stalker who tortured and murdered between eight and twelve individuals in the city of Shreveport, Louisiana, between 1984 and 1987. Among his killings was the mass murder of four members of the Cheney-Culbert family on Cedar Grove in 1985, the crimes for which he was nicknamed The Cedar Grove Killer. Tried for only those murders, he was found guilty and sentenced to death in December 1990.
Early life
Nathaniel Robert Code Jr. was born on March 12, 1956. His parents divorced only six months later and his great aunt Josephine Code and grandfather William T. Code raised him. As a child, Code, who was nicknamed Junior, was noted for his tendencies to stop in the middle of a sentence and stare blankly for a while before continuing. He was alleged to have set fire to animals during his adolescence. After failing ninth-grade, Code dropped out of high school. He began living with his uncle Johnny Boyd shortly after. In 1971, Code was shot four times by Boyd after an argument. Code was able to run four blocks down where he collapsed on the street, and soon after, two patrolmen found him. Code told officers that Boyd, whom he knew as "Uncle Joe," had done it. Boyd was later arrested.
In July 1975, Code was charged with aggravated rape and burglary in connection with the assault of a 20-year-old woman on June 30. He pleaded guilty to attempted aggravated rape in November 1975 and was sentenced to 15 years in prison. While incarcerated, his birth mother died. Code was released on good behavior in January 1984 and began work at Fitzgerald's Contractors, but after a 1985 incident where he attacked a co-worker over a radio-station dispute, Code was fired. On February 3, 1986 he married 27-year-old Vera Code.
Murders
During the night of August 31, 1984 Code entered the home of 25-year-old Debra Ann Ford by pulling open a screen on the bathroom window. After a confrontation in the living room, Code bound Ford's hands and placed a gag on her mouth, then stabbed her multiple times and slit her throat. Ford died as a result of her injuries. Code then fled through the front door. Her body was laying face-down in a sofa. At the time, investigators described the case as "a regular whodunnit." With minimal evidence to pinpoint the perpetrator, a reward of $1,000 was put forward for information leading to an arrest. Code remained elusive.
In the early hours of July 19, 1985, Code committed a mass murder on 72nd Street on Cedar Grove. He killed Vivian Chaney, 34; Billy Joe Harris, 28; Carlitha Culbert, 15; and Jerry Culbert, 25, with what was described as extreme brutality. Billy Joe Harris was shot twice in the head, and twice in the chest, through a pillow. His throat was then slashed and his hands and ankles were bound with shoelaces. Jerry Culbert was shot once in the head while sleeping. Carlitha Culbert was found lying on her stomach, with her hands bound behind her back with an electrical cord from an iron. Her mouth was gagged with duct tape and her shorts were on inside out. Her throat was cut so severely that she was nearly decapitated. Vivian Chaney was found slumped over a bathtub with her hands and ankles bound with a telephone cord. She was beaten and strangled, both manually and with a ligature. Her cause of death was determined to be a combination of manual strangulation and drowning. Her dress contained a large amount of Carlitha Culbert's blood, indicating she was alive and present during her daughter's death. Two other girls in the home at the time, aged 7 and 10, survived. The bodies were discovered at 6:25 a.m. by a relative, Shirley Culbert, who had taken a taxi from a nearby bus station. Police were notified by the taxi driver.
Assistant police chief Sam Burns described the murders by saying, "I don't know that I've seen anything more vicious in the 25 years I've been in the department." According to retired FBI profiler John E. Douglas, the murders of Debra Ann Ford and Carlitha Culbert showed striking similarities, in his words "manipulation, domination, and control of the victims — a calling card. If one occurred in Shreveport and one in Baton Rouge, I wouldn't hesitate. There's no doubt that the same person was responsible for both sets of murders."
On August 5, 1987, Code beat and stabbed his grandfather, 73-year-old William Code, to death. He had stabbed him 13 times and had bound and gagged him. Code also killed two children that were present in the home, 12-year-old Joe Robinson Jr. and 8-year-old Eric Williams. Both boys were bound, gagged, and strangled to death with a cord. Police noted that the brutality of the attack had made them speculate if it was committed by someone close to William.
Code is also suspected, but not confirmed, to have been the killer in the murders of Wes Burks, 48, and Monica Barnum, 20; Burks was killed on June 24, 1985, while Barnum was killed just under a month later on July 18. Code is also suspected in the 1986 murders of Johnny Jenkins, 54, and Jake Mills, 60; Jenkins' body was found at 4115 Miles St. on February 21, 1986, while Mills' body was found at 1549 Poland Ave on December 12, 1986. Code was never officially linked to these killings, and none of his known murders occurred in 1986, the year he was married.
Arrest
Following the last murders, an investigative team interviewed Code at the police station. At the time, he was only a routine suspect because of his relations with one of the victims. According to the authorities, Code made an incriminating statement in the interview while also denying involvement. Code's fingerprints were collected and were matched to evidence found at the scene, and he was arrested. Following his arrest, another fingerprint sample matched a sample collected at the 1985 murders on Cedar Grove, proving his guilt in those killings beyond a reasonable doubt. Finally, with John Douglas' information that modus operandi was the same to Debra Ford's murder, Code's fingerprints were compared, and they matched as well.
Following his arrest, family members and acquaintances of Code came forward with their disbelief that Code was a serial killer. L.C. Thomas, the co-worker whom Code had attacked in 1985, described Code as quick-tempered, while his wife described him as a good, caring man who would never hurt anyone and insisted on his innocence. In total, Code faced eight-counts of first-degree murder. Code denied killing anyone.
Trial
Code was tried only for the murders of the Chaney/Culbert family. The trial began in September 1990. According to prosecutors, Code had stalked each of his victims at night while riding on his bike.
An acquaintance of Code, Oscar Washington, took the stand in late September and testified that he saw Code with blood on his arms between 2 a.m. and 3 a.m. on July 19, 1985. He also claimed that Code had told him he had gotten into a fight and "came out on top". Although on trial for four murders, the prosecution brought up the coroner, who described all of Code's murders, saying that they were all "methodical, controlling, and brutal." Code chose not to take the stand, but his defense presented evidence that Code could not have committed the murders, due to the fact it would take more than one person to kill four people at the same time. They also argued that, if he were to be found guilty, Code should not be sentenced to death due to him having several mental problems, including borderline personality disorder.
By the end of the trial, more than 450 pieces of evidence had been presented, with 106 witnesses having taken the stand. The jury of five men and seven women took only one hour to find Code guilty of four first-degree murder charges. He was sentenced to death.
Incarceration
In July 1991 Code filed an appeal, in which he alleged that he had been overwhelmed during the trial which caused him to make bad legal decisions. He also continually denied committing the murders, contesting that he could not have murdered four people at the same time. His death sentence was upheld by the Louisiana Supreme Court. In August 1994, a Shreveport judge scheduled Code to be executed by lethal injection on September 29 that year. However, due to Code planning to appeal to a federal court, the execution had to be postponed. A new execution date was set for May 15, 1995, but it was delayed once again by a District Judge, who agreed to review documents in the case.
In 2013, Code was one of three inmates at Louisiana State Penitentiary to file lawsuits against the extremely hot temperatures in prison. According to them, they would suffer extreme heat, as high as 195-degree with the heat index in the summer, and said it was a risk of serious harm or death. Family members of Code's victims expressed their extreme rejections toward the request, mentioning what he did to put himself on death row. According to Albert Culbert Jr., the brother of Carlitha Culbert, "He lost all those privileges that you and I have. He lost that air conditioning privilege. He lost that. The Culberts, we didn't put him on death row. He did that when he decided to take my sister's life and my brother, my niece, Billy Joe Harris, Deborah Ford, Mr. William, and the other two little boys. He did that. And now he's got nerve enough…"
See also
Danny Rolling, another serial killer from Shreveport with eight victims
List of death row inmates in the United States
List of serial killers in the United States
Bibliography
External links
State v. Code
References
1956 births
1984 murders in the United States
1985 murders in the United States
1987 murders in the United States
20th-century African-American people
American male criminals
American mass murderers
American murderers of children
American people convicted of murder
American people convicted of rape
American prisoners sentenced to death
Living people
People convicted of murder by Louisiana
People with borderline personality disorder
Prisoners sentenced to death by Louisiana
Serial killers from Louisiana
Serial mass murderers
Stalking
People from Shreveport, Louisiana | Nathaniel Code | [
"Biology"
] | 2,143 | [
"Behavior",
"Aggression",
"Stalking"
] |
70,623,116 | https://en.wikipedia.org/wiki/List%20of%20science%20communicators | This is a list of notable science communicators or popularizers of science, in alphabetical order by last name.
A
John Acorn, naturalist and broadcaster known as the "Nature Nut"
Amir Aczel, Jewish author and mathematician
Maggie Aderin-Pocock, space scientist and broadcaster
Hashem Al-Ghaili, molecular biotechnologist and video producer
Jim Al-Khalili, theoretical physicist, author, and science communicator
Alan Alda, actor, who inspired The Center for Communicating Science
Michael Allaby, writes on science, ecology, and weather
Elise Andrew, British blogger, founder and maintainer of the Facebook page "I Fucking Love Science"
Alberto Angela (born 1962), television presenter, paleontologist, writer, popularizer of science and history.
Piero Angela (1928–2022), journalist, television presenter, writer, popularizer of science, founder of CICAP.
Natalie Angier, science journalist and writer
Isaac Asimov, biochemist, science fiction writer, and author
Peter Atkins, a physical chemist and author
Sir David Attenborough, naturalist and broadcaster
B
Francis Bacon, English philosopher, statesman, scientist, jurist, & author
J. Michael Bailey, a psychologist is best known for his research on the etiology of sexual orientation
Johnny Ball, broadcaster and math popularizer
John D. Barrow, mathematician, theoretical physicist, and cosmologist; author of numerous journal articles, and books for general readers
Marcia Bartusiak, science journalist and author
David Bellamy, broadcaster, author, and botanist
Bob Berman, astronomer
Adrian Berry, science author and columnist
Tim Blais, physicist and YouTuber
Howard Bloom, author
David Bodanis, author
Liz Bonnin, biochemist and TV presenter
Daniel J. Boorstin, author and Librarian of Congress
Sir David Brewster, Scottish scientist
John Brockman, specializing authorship in the scientific literature
Jacob Bronowski, mathematician, biologist, historian of science, author, and pioneering science broadcaster
Michael Brooks, noted for explaining complex scientific research
Bill Bryson, author
Rob Buckman, doctor of medicine, broadcaster, columnist, author
James Burke, broadcaster, television producer, and author; best known for the science historian BBC TV series Connections
C
Nigel Calder, broadcaster and journalist
Dallas Campbell, Presented Bang Goes the Theory
Fritjof Capra, physicist and author
Eugene Thacker, philosopher and author
Sean Carroll, cosmologist, blogger, and author
Rachel Carson, marine biologist, conservationist, author
Manuel Castells, sociologist and writer
Juliana Chan, Singaporean biologist and science communicator
Marcus Chown, author and science journalist
Arthur C. Clarke, science fiction author, inventor, and futurist
Brian Clegg, author
Jack Cohen, reproductive biologist
Lee Constable, television presenter, author, and biologist
Heather Couper, astronomer, broadcaster, and author
Jacques-Yves Cousteau, Oceanographer, underwater explorer, conservationist, filmmaker, and broadcaster
Brian Cox, broadcaster, musician, and physicist
Michael Crichton, medical doctor, author, filmmaker
Francis Crick, molecular biologist, biophysicist, and neuroscientist; joint discoverer of the structure of the DNA molecule
Jon Culshaw, impressionist, also occasionally appears as a presenter on The Sky at Night
D
Antonio Damasio, neuroscientist and writer
Tobias Dantzig, mathematician and author
Paul Davies, physicist, author, and broadcaster
Richard Dawkins, evolutionary biologist and author
Michael DeBakey, world-renowned cardiac surgeon, innovator, and author
Daniel Dennett, philosopher, cognitive scientist and author
Keith Devlin, mathematician and author
Alexander Dewdney, mathematician, computer scientist, and philosopher
Jared Diamond, evolutionary biologist, physiologist and geographer
Ann Druyan, science writer, co-author with (and widow of) Carl Sagan
Robin Dunbar, anthropology; evolutionary psychology, culture and language; and specialist in primate behavior
Marcus Du Sautoy, author, broadcaster, Professor of Mathematics
E
David Eagleman, neuroscientist and author
Sir Arthur Eddington, astrophysicist
Gerald Edelman, from the immune system, analogously, to brain & mind
Loren Eiseley, Professor of Anthropology and History of Science
Jordan Ellenberg, mathematician and author
F
Peter Fairley, journalist and broadcaster
Michael Faraday, scientist and lecturer
Kenneth Feder, archaeologist, skeptic, lecturer, and author
Timothy Ferris, science writer and best-selling author of twelve books
Richard Feynman, physicist and author
Brian J. Ford, biologist, lecturer, and author
Anna Frebel, astrophysicist and author
Morgan Freeman, actor and host for TV's Through the Wormhole
G
George Gamow, physicist, cosmologist, and author
Martin Gardner, mathematician, author, skeptic & polymath
Atul Gawande, surgeon and author
Malcolm Gladwell, journalist and author
James Gleick, author and journalist
Marcelo Gleiser, physicist and astronomer
Ben Goldacre, medical doctor, psychiatrist, and author
Stephen Jay Gould, paleontologist, evolutionary biologist, and science historian; author of numerous essays, articles, and books
Steve Grand, computer scientist and roboticist
Hank Green, entrepreneur, musician, and vlogger
Brian Greene, physicist
Susan Greenfield, brain physiologist, writer and broadcaster
Richard Gregory, neuropsychologist, author and editor of several books
John Gribbin, astronomer and author
H
Heinz Haber, physicist and author
Margherita Hack, astrophysicist, writer and activist
Gunther von Hagens, german anatomist and pathologist, inventor of plastination and creator of Body Worlds
Thomas Hager, author and science journalist
J. B. S. Haldane, biologist and author
Jack Hanna, zoologist, broadcaster, author
Brady Haran, filmmaker
Yuval Noah Harari, historian, professor, and writer
Bas Haring, philosopher and author
Sam Harris, neuroscientist and author
Lucy Hawking, journalist and daughter of Stephen Hawking
Stephen Hawking, theoretical physicist and author
Ed Hawkins, British climatologist who developed warming stripes and other graphics
Katharine Hayhoe, Canadian climate scientist and author
Hetty Helsmoortel, Belgian scientist, author, founder of the Nerdland Festival
Don Herbert, a.k.a. Mr. Wizard, broadcaster
Roald Hoffmann, chemist
Douglas Hofstadter, computer scientist, cognitive scientist, and author
Lancelot Hogben, experimental zoologist and medical statistician, with many popularising books on science, mathematics, and language
Sabine Hossenfelder, a theoretical physicist who researches quantum gravity
Fred Hoyle, British astronomer
Julian Huxley, eminent scientist, author, and first Director of UNESCO
Jamie Hyneman, special effects artist and TV personality (MythBusters)
I
Jay Ingram, broadcaster and author (Daily Planet)
Steve Irwin, wildlife expert and conservationist; TV personality of the worldwide-fame wildlife documentary TV series (The Crocodile Hunter)
J
Hope Jahren, geochemist and author
Ray Jayawardhana, astrophysicist and author
Donald Carl Johanson, paleoanthropologist and author
Steven Johnson, author
Steve Jones, evolutionary biologist and author
Horace Freeland Judson, historian of molecular biology and author
Olivia Judson, evolutionary biologist, broadcaster and author
K
Michio Kaku, theoretical physicist and author
Sam Kean, author
Marek Kukula, Public Astronomer at the Royal Observatory, Greenwich
Lawrence Krauss, physicist and author
Robert Krulwich, broadcaster
Karl Kruszelnicki, a.k.a. Dr Karl, broadcaster
L
Lynne Lamberg, American freelance science journalist
Richard Leakey, Kenyan paleoanthropologist and conservationist
John Lennox, mathematician and author
Edward M. Lerner, computer engineer and author
Daniel Levitin, a cognitive neuroscientist and author
Roger Lewin, British anthropologist
Richard Lewontin, evolutionary biologist, geneticist, and author
Willy Ley, space travel enthusiast and science writer ("Prophet of the Space Age")
Don Lincoln, particle physicist and author
Chris Lintott, astrophysicist
Avi Loeb, astronomer and author
M
Bob McDonald, CBC journalist and host of Quirks and Quarks
Alister McGrath, molecular biologist and author
Katie Mack, astrophysics professor who focuses on studying dark matter
Lynn Margulis, evolutionary biologist and author
Robert Matthews, physicist, mathematician, computer scientist, and distinguished science journalist
Danica McKellar, actress, author, mathematician
Terrence McKenna, ethnobotanist, lecturer, and author
Peter Medawar, biologist, called by Richard Dawkins "the wittiest of all scientific writers" and by New Scientist "perhaps the best science writer of his generation".
Fulvio Melia, physicist, astrophysicist, and author
Ben Miller, English comedian and hosted shows such as It's Not Rocket Science (TV series)
Julius Sumner Miller, physicist and broadcaster
Mark Miodownik, materials scientist, engineer, broadcaster, and writer
Ashley Montagu, anthropologist and humanist, authored by over 60 books
Sir Patrick Moore, amateur astronomer and broadcaster
Desmond Morris, zoologist, ethologist and author
Hamilton Morris, pharmacologist, broadcaster, and author
Philip Morrison, physicist, known for his numerous books & TV programs
Siddhartha Mukherjee, oncologist, biologist, author
Derek Muller, science-based youtube content creator
Randall Munroe, writer of What if blog
PZ Myers, professor and author of the science blog Pharyngula
N
Yoshiro Nakamatsu, Japanese inventor
Jayant Narlikar, cosmologist and author
Steven Novella, skeptic and advocate of science-based medicine
Eugene P. Northrop, research mathematician and math popularizer
Bill Nye, actor, mechanical engineer, branded as "The Science Guy"
Tor Nørretranders, author
O
Sten Odenwald, astronomer, author, lecturer
Robert Olby, author and historian of science
Chad Orzel, physicist and author
P
Kasha Patel, comedian and science writer
Linus Pauling, biochemist, author, and educator
John Allen Paulos, mathematician and author
Fred Pearce, journalist at New Scientist
Yakov I. Perelman, author
Wendell Phillips, archaeologist
Steven Pinker, experimental psychologist, cognitive scientist, linguist, and author
Phil Plait, astronomer and skeptic who runs the Bad Astronomy website
Martyn Poliakoff, British chemist, featured in the YouTube The Periodic Table of Videos series
John Polkinghorne, physicist and author
Robert Pollack, biologist and author
Michael Pollan, journalist and author, professor
Carolyn Porco, leader of Cassini Imaging Team
Roy Porter, prolific work on the history of medicine
Christopher Potter, publisher, philosopher and author
Eduard Punset, politician, lawyer, economist, and science popularizer
Magnus Pyke, food scientist, broadcaster, and author
R
V. S. Ramachandran, neuroscientist, cognitive scientist, and author
James Randi, stage magician, skeptic, and author
Lisa Randall, theoretical physicist and author
Mark Ridley, zoologist, evolutionary scientist and author
Matt Ridley, zoologist, journalist and author
Alice Roberts, anatomist, anthropologist, television presenter, and author
Steven Rose, biologist, neurobiologist, broadcaster and author
Carlo Rovelli, theoretical physicist and author
S
Oliver Sacks, neurologist and author
Carl Sagan, astrobiologist, astronomer, broadcaster, and author
Kirsten Sanford, neurophysiologist and broadcaster
Laurie Santos, cognitive scientist, professor of psychology, and host of The Happiness Lab
Adam Savage, special effects artist and TV personality (MythBusters)
Walter Warwick Sawyer (or W. W. Sawyer), mathematician, mathematics educator, and author
Eric Scerri, chemist, historian and philosopher of science, and author
Lieven Scheire, Belgian comedian, science communicator, founder of the Nerdland Podcast
Joseph A. Schwarcz, chemist, author, TV and radio host
Garrett P. Serviss, American astronomer and science fiction writer
Tali Sharot, cognitive neuroscientist and writer
Seth Shostak, astronomer, broadcaster, and author
Neil Shubin, paleontologist, evolutionary biologist
George Gaylord Simpson, paleontologist, zoologist and author
Simon Singh, physicist, mathematician, and author
Edwin Emery Slosson, chemist, journalist, and editor
Laura J. Snyder, historian, philosopher, and author
Mary Somerville, polymath, mathematician, and author
Paul Stamets, mycologist and author
Michael Stevens, science-based YouTube content creator
Iain Stewart, geologist and broadcaster
Ian Stewart, mathematician and author
David Suzuki, broadcaster, geneticist, and environmental activist
Daniel Swain, meteorologist
T
Lewis Thomas, physician, poet, etymologist, and essayist
Chriet Titulaer, Dutch astronomer, author, and broadcaster
Colin Tudge, biologist and author
Neil deGrasse Tyson, astrophysicist and author
W
Kenneth Walker (author), surgeon and author
Alie Ward, television and podcast host
Fred Watson, astrophysicist, musician, and author
James D. Watson, molecular biologist, geneticist, and zoologist
Kevin Warwick, biomedical scientist, roboticist, and author
Victor Weisskopf, physicist, science administrator and author
Michael White, musician and science writer
Norbert Wiener, mathematician, author; the father of cybernetics
Simon Winchester, geologist and author
Robert Winston, medical doctor, scientist, TV presenter, and author
Richard Wiseman, psychologist and author
Stephen Wolfram, mathematics, theoretical physics, scientific computing
Lewis Wolpert, developmental biologist, author, and broadcaster
Peter Wothers, chemist and author
Andrea Wulf, author
Z
Paul Zaloom, the actor who portrayed an eccentric scientist on the children's TV show Beakman's World 1992–1998
Carl Zimmer, science writer and author of the science blog The Loom
Marlene Zuk, evolutionary biologist and behavioral ecologist
See also
References
Science communicators
Lists of people in STEM fields | List of science communicators | [
"Technology"
] | 2,863 | [
"Lists of people in STEM fields"
] |
70,623,170 | https://en.wikipedia.org/wiki/Phaeoceros%20carolinianus | Phaeoceros carolinianus is a species of hornwort—a group of simple, non-vascular plants—that is found worldwide in damp, shaded areas. It forms flat, dark green, rosette-shaped patches measuring 10–20 mm in diameter on bare soil and rock surfaces. The plant is characterised by its horn-like spore capsules, which grow 40–60 mm tall, and for producing both male and female reproductive structures on the same plant (a monoicous condition). These features, along with its unique spore structure, distinguish it from closely related species like P. laevis.
First described by the French botanist André Michaux in 1803 from specimens collected in the Carolinas, Phaeoceros carolinianus has a complex taxonomic history and was later assigned to the genus Phaeoceros by Johannes Max Proskauer in 1951. While it often behaves as an annual plant in temporary habitats such as arable fields, it can persist longer in continuously moist environments and survive dry periods by forming tuber-like structures. The species is not only important ecologically but has also been developed as a model organism for genetic research due to its simple morphology and ease of cultivation.
Systematics
Historical taxonomy
The genus Phaeoceros, which was erected by Johannes Max Proskauer in 1951 and currently includes about 40 accepted species, is characterised by solid, smooth thalli, antheridial chambers typically containing 1–8 antheridia, and capsules without a distinct line of dehiscence.
The French botanist André Michaux first described the species in 1803 from Carolinas specimens, originally naming it Anthoceros carolinianus. Several previously described species have since been recognised as synonyms, including Anthoceros australiae, A. brotheri, A. communis, and A. multicapsulus.
The taxonomic history of the species has been complex. Proskauer initially studied these hornworts as part of the genus Anthoceros in 1948, but after detailed morphological studies, he created the genus Phaeoceros in 1951 specifically to accommodate the yellow-spored species, leaving only black-spored taxa in Anthoceros. At this time, he also separated P. carolinianus from P. laevis based on its reproductive condition and chromosome morphology. However, by 1958, after observing considerable variability in specimens from many countries, Proskauer temporarily merged them as subspecies, treating the taxon as P. laevis subsp. carolinianus.
Decades of taxonomic confusion led Proskauer to propose that there was one species, P. laevis, with two subspecies: dioicous laevis in the Mediterranean and monoicous carolinianus worldwide. This taxonomic treatment was widely adopted and remained in use through the 1970s and early 1980s.
The difficulty in distinguishing these taxa was compounded by the challenges of observing their reproductive condition. Even in monoicous P. carolinianus, the timing of male and female reproductive structure development can make it hard to confirm its reproductive status. Plants may initially produce only antheridia, with archegonia appearing weeks later, while those growing in deep shade may remain purely vegetative. Additionally, as older parts of the thallus decay, it becomes difficult to locate evidence of previous antheridial cavities.
The taxonomic resolution came through detailed studies in the 1980s, particularly through scanning electron microscopy of type specimens. In 1987, Hässel de Menéndez determined these taxa should be treated as separate species based on detailed studies of spore morphology. This separation was supported by differences in chromosome morphology, spore size, and distinctive spore ornamentation patterns. The spores of P. carolinianus feature distinct surface patterns, including short-pointed spines on the distal surface (up to 2 μm long at center, 0.5 μm at border) and 17–21 spines across the diameter, while the proximal surface has a well-defined trilete mark ending near the rim in an obtuse angle, with triangular areas showing fine, interwoven, noodle-like ornamentation.
Classification
Phaeoceros carolinianus belongs to the subclass Notothylatidae of the class Anthocerotopsida. Within this, it is placed in the order Notothyladales and family Notothyladaceae, alongside its close relatives in the genera Phaeoceros and Notothylas.
Description
Phaeoceros carolinianus is a hornwort that forms flat, dark green, rosette-shaped patches on the ground. The plant body consists of two main parts: the gametophyte (the main vegetative body) and the sporophyte (the reproductive structure). The gametophyte consists of a flattened, branching thallus that grows 10–20 mm long and 5–10 mm wide. The thallus has a smooth margin and lacks specialised reproductive structures called gemmae. A distinctive feature of its cells is that each contains a single large chloroplast with a central pyrenoid (a protein structure involved in carbon fixation). On its underside, the thallus produces two types of root-like structures called rhizoids: smooth, transparent ones and pale brown (warty) ones. The thallus hosts colonies of Nostoc, a cyanobacterium visible as dark spots on the lower surface.
The cellular organisation of P. carolinianus shows several distinctive features. Each cell is monoplastidic, containing a single large chloroplast with a pyrenoid-based carbon-concentrating mechanism, a feature that distinguishes it from most other land plants. The chloroplast contains extensive grana stacks and channel thylakoids. The cytoplasm contains typical plant cell organelles including mitochondria, Golgi bodies, and an endoplasmic reticulum network that extends throughout the cell. Within the thallus, cells are connected by plasmodesmata, allowing for intercellular communication.
The thallus shows limited tissue differentiation compared to vascular plants, but maintains specialized regions including photosynthetic tissue and regions colonized by symbiotic cyanobacteria which appear as dark spots scattered throughout the plant's lower surface. These cyanobacterial colonies are housed in mucilage-filled cavities within the thallus tissue. The surface cells produce two types of rhizoids: smooth, transparent ones and pale brown tuberculate (warty) ones.
Phaeoceros carolinianus is distinguished by its sporophyte, a horn-like structure that emerges vertically from the thallus. These horn-like structures reach 40–60 mm in height, with spores developing progressively from base to tip. Each sporophyte comprises a foot anchored in parent tissue and an elongated, spore-producing capsule. The capsule wall contains small pores called stomata and has layers of photosynthetic tissue beneath its surface. At maturity, the capsule splits lengthwise into two parts to release bright yellow spores that measure 32.5–42.3 micrometres (μm) in diameter. These spores have a distinctive surface pattern, with spine-like projections on one face and smaller bumps arranged in a triangular pattern on the other face. Among the spores are sterile cells called pseudoelaters, which are pale brown, smooth, and usually branched.
The species can reproduce sexually, producing both male and female reproductive structures on the same plant (monoicous). The male structures (antheridia) mature before the female structures (archegonia), with each male chamber containing between one and eight antheridia that turn yellow-orange when mature.
The spore wall has six layers, with spine-like projections on one side and small bumps () on the other. The bright yellow spores measure 42–47 (up to 49) μm in diameter, with the spine-like projections measuring about 2 μm long in the centre and 0.5 μm at the border. When examined with an electron microscope, the spore wall reveals (from inside to outer surface): a thin inner layer, a thick loose outer layer, a homogeneous middle layer that forms the surface ornamentations, and three additional outer coating layers of varying thickness. This complex wall structure provides protection and likely facilitates spore dispersal. Unlike some other hornworts, P. carolinianus has a particularly complex spore wall structure that suggests it is relatively advanced evolutionarily within the group. The proximal face of the spores has a nearly smooth or finely granulate surface with scattered, minute papillae only in the central part of each face, while the distal face is densely papillate to spinulate throughout, with 17–21 spines across the diameter. These spore characteristics are important diagnostic features that help distinguish P. carolinianus from the closely related P. laevis, which has densely papillate proximal surfaces.
The gametophyte shows some seasonal variation in its growth and reproduction. Sexual organs (antheridia) are produced from September to May. While it can survive as an annual plant in temporary habitats like arable fields, it is also known to form tuber-like thickenings containing rhizoids within or on the ventral surface of the thallus, which help it survive periods of desiccation. In Britain, the sporophytes occur seasonally from September to December.
Life cycle and growth
In temperate regions, P. carolinianus typically follows an annual life cycle, though it can persist as a facultative perennial in some regions like the southern Appalachians. The gametophytes show a mean growth rate of 0.1 mm per day under field conditions, enabling them to reach diameters of 20–30 mm over a three-month growing season. Individual plants can survive and grow for up to 18 months under favourable conditions.
Sexual reproduction begins commences weeks after germination as male and female reproductive structures develop on the same plant (monoicous condition). The male structures (antheridia) mature before the female structures (archegonia). Sporophytes emerge 3–4 weeks after germination once plants attain a minimum diameter of 3 mm. Each plant typically produces between 4.5 to 23 sporophytes over a growing season, with spores maturing progressively from the base to tip of each capsule.
Similar species
Phaeoceros carolinianus differs from the similar species P. perpusillus and P. exiguus in several morphological features. While all three species are monoicous, P. carolinianus has a thicker thallus (8–13 cells thick in the middle versus 6–9 cells), taller involucres (2–4 mm versus 1–2 mm), and significantly longer capsules (2–4 cm versus less than 1.5 mm). Its spores are smaller (30–37 μm versus 40–47 μm) with distinctive ornamentation, showing minute papillae only in the central part of each proximal face. P. carolinianus also has notably longer pseudoelaters (length/width ratio >5) compared to the other species.
In field settings, P. carolinianus can be found growing alongside other hornwort species. In Croatia, it has been documented growing with Anthoceros agrestis and Notothylas orbicularis, forming part of the plant community Riccio glaucae-Anthocerotetum crispuli, which typically develops on temporary dry and loamy soils.
Distribution
Phaeoceros carolinianus has a subcosmopolitan distribution, spanning temperate and tropical regions globally. In Europe, it is found from the Mediterranean to northern regions, in Asia it occurs across temperate and tropical areas, and in North America it ranges from Canada to Mexico and the Antilles. In the Southern Hemisphere, it has been documented in Australia, New Zealand, various parts of Africa, and South America including Colombia, Peru, Brazil, Chile, Bolivia, and Argentina.
In Australia, the species occurs across all Australian states including Australian Capital Territory, New South Wales, Queensland, South Australia, Tasmania, Victoria, and Western Australia, as well as Lord Howe Island and Norfolk Island.
In Southeast Europe, the species was historically sparsely documented. It was recorded in Croatia in 2018, where it was found growing on open ground with other hornworts in Central Croatia. Outside Croatia, in Southeast Europe it has been documented from Romania, where it is considered critically endangered, Slovenia, where it is considered data deficient, and Bulgaria, where it is also listed as data deficient.
In North America it ranges from Canada to Mexico and the Antilles, including Dominica. In the United States, the species is well-documented in Missouri, where it has been reported from 27 counties, making it the most frequently recorded hornwort species in the state. Its presence has been confirmed across diverse regions of Missouri, with specimens collected and verified over many decades from the early 1900s to recent times.
Despite considerable morphological variation across its range, the species maintains consistent defining characteristics, particularly its monoicous condition and distinctive spore ornamentation.
Habitat and ecology
Phaeoceros carolinianus grows on bare soil, forming fans, rosettes, patches or mats that adhere to the substrate. It shows a preference for fresh to moist, sandy-loamy or sandy soils that are neutral to slightly acidic, and can grow in conditions ranging from full light to shade.
The species occurs in both natural and anthropogenic habitats. In nature, it grows along bush tracks, roadsides, and waterways banks, especially in damp, shaded areas. In Bolivia, it colonises wet soil and rock slopes with water seepage at elevations around , forming rosettes 2–4 cm in diameter, while in Dominica it has been documented on shaded earth slopes at elevation.
In agricultural landscapes, it is particularly associated with cultivated fields, especially stubble fields after harvest, and less frequently in other crops such as corn, vegetables, or fallow fields. The species also colonises field margins, forest edges, ditches, path edges, and pond margins. In Switzerland, it occurs from colline to montane elevations (), primarily in agricultural areas of the Central Plateau, Jura, and Southern Alps, where despite abundant spore production, populations typically remain relatively small and stable compared to other hornwort species.
The species is frequently associated with other bryophytes in the plant community Riccio glaucae-Anthocerotetum, particularly in areas with temporary dry and loamy soils. In Central Europe, it typically behaves as an annual species, being frost-sensitive and developing during summer to autumn months, though it may persist longer in sites that maintain sufficient moisture for continuous growth.
Conservation
Phaeoceros carolinianus faces several conservation challenges across its range. In Europe, the species has experienced population declines over recent decades, primarily attributed to changes in agricultural practices. The main threats include intensification of farming methods, particularly earlier and more frequent tillage operations that reduce the time available for the species to complete its life cycle. The use of agricultural chemicals and fertilisers may also impact populations, though to a lesser extent.
In Switzerland, the species is classified as endangered (EN) and is legally protected nationwide. It has been designated as a species of medium national priority for conservation, requiring clear action plans and targeted species promotion measures. The species' conservation status varies across Southeast Europe, where it appears to be either rare or understudied. It is classified as critically endangered (CR) in Romania and data deficient (DD) in both Slovenia and Bulgaria. The abandonment of traditional agriculture and subsequent succession of arable land to woodland represents an additional threat to populations in some regions.
As an ephemeral species with specific habitat needs, P. carolinianus is especially vulnerable to land-use changes. The species requires temporarily open, disturbed ground with sufficient moisture, typically found in traditional agricultural settings. Modern intensive farming practices often do not provide suitable conditions for the completion of its life cycle, which requires several weeks from spore germination to mature sporophyte development. Conservation efforts are hindered by limited knowledge of its distribution and population dynamics in many regions, highlighting the need for comprehensive surveys and monitoring programs.
Research use
Phaeoceros carolinianus has been developed as a genetically tractable experimental system, with successful Agrobacterium-mediated genetic transformation achieved in 2023. The species can be maintained in axenic (sterile) culture on KNOP medium and propagated vegetatively with monthly subculturing. Its simple thallus morphology and relatively flat growth make it useful for cellular imaging studies, particularly for investigating fundamental aspects of plant cell biology such as cell polarity, plasmodesmata-related processes, and cell division.
Several features make P. carolinianus particularly valuable for studying plant evolution and development. Its single chloroplast per cell (monoplastidic condition) with a pyrenoid-based carbon-concentrating mechanism is unique among land plants, offering insights into the evolution of photosynthetic systems. The species also forms symbiotic relationships with cyanobacteria, providing opportunities to study plant-microbe interactions that are relatively rare among land plants. The development of genetic transformation techniques for P. carolinianus has enabled the use of fluorescent proteins to study cellular structures and processes, including the visualisation of organelles such as mitochondria, chloroplasts, and the endoplasmic reticulum.
References
Hornworts
Flora of Australia
Flora of New Zealand
Flora of Africa
Flora of Southern America
Flora of Europe
Flora of Northern America
Plants described in 1803
Taxa named by André Michaux
Cosmopolitan species
Near threatened biota of Europe | Phaeoceros carolinianus | [
"Biology"
] | 3,684 | [
"Cosmopolitan species",
"Organisms by location"
] |
70,624,318 | https://en.wikipedia.org/wiki/Nir%20Ben-Tal | Nir Ben-Tal (Hebrew: ניר בן-טל) is the Abraham E. Kazan Chair of Structural Biology at Tel Aviv University.
Early life
Nir Ben-Tal is a professor at Tel Aviv University, where he has held the Abraham E. Kazan Chair of Structural Biology since 2018 as a member of the School of Neurobiology, Biochemistry & Biophysics. He received his undergraduate degree in Biology, Chemistry and Physics from the Hebrew University of Jerusalem in 1988 and his DSc in Chemistry at the Technion, Israel Institute of Technology, in 1993.
Career
His research group at Tel Aviv University developed Conservation Surface Mapping (ConSurf) in response to certain algorithmic limitations. He received a 2018 NATO Science for Peace and Security Programme Prize in radiological and nuclear (CBRN) defence for his project “The Anthrax MntABC Transporter: Structure, Functional Dynamics and Drug Discovery”.
In 2022 he co-authored the book From Molecules to Cells: The Origin of Life on Earth, which hypothesizes on the beginning of life on Earth. Over his career he has published articles in scientific journals as well as scientific textbooks such as Introduction to Proteins: Structure, Function and Motion.
References
Year of birth missing (living people)
Living people
Academic staff of Tel Aviv University
Structural biologists
Israeli biologists
Hebrew University of Jerusalem alumni
Technion – Israel Institute of Technology alumni | Nir Ben-Tal | [
"Chemistry"
] | 288 | [
"Structural biologists",
"Structural biology"
] |
70,627,195 | https://en.wikipedia.org/wiki/Trichophyton%20erinacei | Trichophyton erinacei is a species in the fungal genus Trichophyton that is associated with hedgehogs. The fungi is normally isolated from the quills and underbelly of hedgehogs. Common symptoms of infection include crusting around the face and loss of spines. Trichophyton erinacei is also known to affect humans through hedgehog contact that transmits the fungi. Infections can also occur with indirect contact.
References
Arthrodermataceae
Animal fungal diseases
Fungus species | Trichophyton erinacei | [
"Biology"
] | 103 | [
"Fungi",
"Fungus species"
] |
70,628,114 | https://en.wikipedia.org/wiki/Toco%20toucan%20beak | The beak of the toco toucan is integral to their vital social, feeding, foraging, and nest building behaviors. Since the toucan beak does not fully regenerate, it is evolutionarily favorable for it to have robust mechanical properties while still being light enough to allow flight. The beak makes up one-third of the toucan's body length, while contributing to less than three percent of the toucan's weight. The beak structure largely influences its mechanical properties and the lifestyle of the toucan. The beak's properties are increasingly becoming popular in the realm of biomimicry as several industries such as architecture, transportation, and protective equipment can utilize trends of the biological beak structure in manmade designs.
Structure
Outer beak
The toucan beak has a synergistic sandwich structure with a thin rigid outer shell encapsulating the bulk of the volume which is a cellular solid. The exterior layer, known as the rhamphotheca, is composed of several layers of overlapping sheets of beta keratin . Each keratin sublayer is between 2 and 10 micrometers thick with the entire rhamphotheca stack being 0.5 to 0.75 mm thick, varying by position along the length of the beak. Hexagonal keratin cells with a diameter around 50 micrometers make up the majority of the laminate shell. Each cell boundary and interior are interwoven with a matrix of intermediate filaments with randomly distributed orientations, allowing for the isotropic character of the material. The purpose of the matrix is to act as a viscoelastic medium for dispersing severe impacts to the beak over a greater area, to reduce the effects of local imperfections, protecting it from cracking damage.
Hydroxyapatite mineralization is present but to a lesser extent than in the inner foam. Keratin in the rhamphotheca of the toucan beak has a much lower abundance of sulfur, and therefore the amino acid, cystine, compared to other keratin structures like hair. This indicates less disulfide crosslinking.
Inner beak
The inner beak is a collagen foam, with a high glycine content and subsequent hardness as in most bones. The fibrous network of collagen trabeculae varies from 70 to 200 micrometers in thickness and are often hollow with an edge connectivity of 3 or above. These, along with even thinner (2 to 25 micrometer) membranes characterize a closed cell foam network which provides the optimal strength at low density for flight consideration. The membranes and trabeculae have higher calcium mineralization content than the dense outer beak. Micro- and nano- indentation testing supports the notion that the inner collagen trabeculae are stronger pound for pound than the outer shell.
Mechanical and material properties
Research has been conducted in order to determine mechanical and material properties of the Toucan Beak. The apparent density of the overall beak is estimated to be between 0.1 and 0.25 grams per cubic centimeter.
Outer beak properties
The exterior shell of the beak, the rhamphotheca, has a tensile strength of around 50 MPa and a Young's Modulus of 6.7 GPa. From testing the keratin-layer of the beak, it was found the mean value of the Yield Strength is 30 MPa. Further, the yield strength of the beak is sensitive to the strain rate and is associated with the viscoelasticity of the inter-scale glue for the keratin scales. When the yield stress of the beak nears or exceeds the ultimate tensile strength, the fracture of the keratin scales is preferred for the beak over the viscoelastic deformation of the inter-scale glue. In regard to the Young's Modulus and Yield Strength of the keratin in the beak, these values do not change along the longitudinal and transverse direction. The keratin shell can therefore be considered transversely isotropic. The fracture modes of the keratin shell demonstrate a dependence on the strain rate at which the fracture occurs. Testing at lower strain rates revealed a slipping of the scales that is a result of the organic glue being released. For higher strain rates, the keratin scales fractured. Hardness tests were conducted to determine microhardness and nanohardness values for the keratin shell, which are 0.22 ± 0.01 GPa and 0.48 ± 0.06 GPa, respectively.
Inner beak properties
For the internal foam part of the toucan beak, which is composed of trabeculae, the Young's Modulus was found to be 12.7 GPa, which is higher than that of the outer shell. This difference is due to the calcium content being higher in the foam than that in the keratin shell. The relative density of the foam was found to be 0.09. [6] Tests were conducted to determine the hardness values of the trabecula. The Microhardness value was found to be 0.28 ± 0.03 GPa, and the nano-hardness value was found to be 0.55 ± 0.12 GPa. For the foam of the beak, the crushing stress increased with its density. The mean value found for crushing stress is 0.17 MPa.
Functions
The toucan beak serves several functional roles for the toucan such as acting as a thermal regulator for heat exchange, a tool in feeding, and a method of defense. The toucan has an extreme beak size, with the beak accounting for approximately forty percent of the bird's total body surface area. When compared to other birds, it is noted that the toucan is exposed to some of the warmest monthly temperatures and has the longest beak length. Geographic and temperature variation in beak size has been presumed to relate to resource exploitation and reproduction. Many early researchers assumed to associate beak size with sex-specific traits such as mate selection or vocalization. However, more recently the beak has more closely been linked to its role in physiological homeostasis.
Thermoregulation
As endothermic organisms, toucans produce their own body heat through metabolism and regulate their body temperature through heat exchange with the environment. Such a heat exchange process occurs usually within an enlarged, uninsulated and well vascularized appendage where blood is able to flow to allow for efficient heat exchange. The toucan beak has a network of superficial blood vessels that support the rhamphotheca, the horny sheath of the bill. The toucan is able to dilate or enlarge the beak's blood vessels when temperatures rise above a thermal neutral zone to allow for blood to pass readily into the beak, allowing for heat exchange and cooling. While below the thermal neutral zone the vessels constrict in order to allow for conservation of metabolic heat. Research has shown that at warmer temperatures, heat is observed throughout the length of the beak in both adult and young toucans, indicating that heat release through the beak is done to cool the toucan body. In colder temperatures, the beak largely maintains the ambient temperature of the environment with only the proximal beak showing warmer temperatures, demonstrating that blood may be shunted away from the beak and kept flowing mostly within the body to maintain warmth. Other research shows that the toucan bill's foam interior and ability to quickly transfer heat renders the bill a liability in colder climates and is the typical reason why toucans commonly sleep with their bills tucked beneath their wings to help aid in heat conservation.
Feeding
Toucans are omnivorous and feed on food of both plant and animal origin. The large size of the toucan bill enables the bird to crack larger seeds for fuel and easily grasp fruits, vegetables, insects, eggs, and small birds. The longer length of their bill allows toucans to pluck fruit from the tips of tree branches without requiring them to leave a stable position on another branch or perch. The structure of the toucan bill has serrations similar to those of a knife which allows them to easily tear food apart and peel fruits.
Defense
Toucans have natural predators such as forest eagles, hawks, and owls. The birds must also defend themselves from boas, jaguars and margays who sometimes invade toucan nests. To protect themselves, toucans rely heavily on their loud voices that aim to scare off enemies and alert other toucans to the threat of danger. In addition, toucans will strike their bill against a tree or branch as a defensive display of strength. The toucan bill can withstand such compressive strikes against branches due to its previously described structure. Other defensive acts include toucans consuming small baby birds or eggs of other birds. The extreme size of the toucan's bill provides defensive assistance since smaller birds are frightened by both the size and bright colors of the bill. The toucan's beak and its strength, however, are only useful in defense while perched; other birds typically only attack a toucan while it is in flight since the bird cannot defend itself with its beak while flying.
Biomimicry
The unique properties of the toco toucan beak make it a viable option for biomimetic designs, or systems modeled on biological entities. Toucan beaks are responsible for only one twentieth of the entire mass of the creature allowing the bird to fly even with its massive beak. As previously mentioned, the keratin shell and closed-cell foam organization in the toucan beak plays a role in the beak's characteristic energy absorption, compressive resistance, high stiffness and strength features. Additionally, toucan beaks also have insulation capacities. All of the properties of the toucan beak in tandem with its low weight make the beak a valuable biological entity to study for a variety of design applications. However, there are currently only a few applications of the toucan and its beak in biomimetic models.
Architecture
For example, Brazilian biologist and architect Alessandra Araujo aided in the design of the Votu Hotel in Bahia, Brazil. This hotel was aimed to maintain and support the region's native species. Araujo employed various biomimetic designs for the hotel, such as how prairie dogs utilize burrows to insulate from extreme heat, the saguaro cactus' self-shading ability, and the native bird - the toco toucan - beak which plays a role as an extremely efficient thermal regulator. Specifically in the layout of the hotel, Araujo chose to design the kitchens of the rooms at the Votu hotel after the toco toucan's beak. Since one of the goals of this hotel was to minimize air conditioning and electricity consumption, the kitchen schematics were inspired by the toucan's ability to live with large temperature swings like having extremely hot days and cool nights. As the heat produced in the kitchen areas rises to the ceiling, it is drawn into a copper coil that passes through rooftop soil on the hotel. Air cools in the shade of a rooftop garden, and eventually returns to the kitchen. This system allows the hotel to have a natural air conditioner which requires no additional energy.
Protective equipment
Many potential biomimetic applications based on the characteristics of the toucan beak are currently hypothetical ideas that have not yet been employed. Among the most popular ideas is using the toucan beak to design personal protective wear like helmets. Helmets are very important for the safety of individuals riding bikes, motorcycles, for rock climbers, athletes, and more. However, the heavy, awkward, and uncomfortable wear of helmets can lead to people taking them off and risking a head injury. By integrating characteristics of a toucan beak into new helmet design, the risk of head injury might decrease since new designs may provide a more comfortable, lighter, thinner, but stronger protective piece. Such new helmets or protective equipment draw inspiration from toucan beaks by having a light mass but immense strength. Additionally, the aesthetic of these new helmets could be improved with a thinner, less bulky design, and could eliminate the hesitation to wear helmets because of their unpleasing appearance. Similar to helmets, the toucan beak features could also be incorporated into football crash pads and other protective gear whose innovative design would reduce bulkiness prevent interference with activity performance. Some current protective wear inhibits athletic ability, such as bulky knee pads hindering skaters’ speeds.
Other
More general possible applications for the toucan beak design are creating crash resistant vehicles without compromising fuel economy. These possibilities can draw on the toucan beak's energy absorption capacity created by its structural properties. A famous materials researcher, Meyers, studied toucan beaks extensively and suggested another application for cars; the creation of car panels that are lighter, stronger, and safer than current panels. Meyers also noted the ability for the toucan beak design, specifically the ultra-lightness, to be incorporated into aircraft or other vehicle components.
Another situation in which the toucan, though not specifically the beak features, was employed was for the "Beak Laser Projector". This projector" is a portable projector drawing inspiration from the toucan's ability to tuck its long beak against its neck and under its wings. This design allowed the projector to achieve its goal of "skull" rotation and simultaneously provided a product with better usability, convenience, and most compact form.
In popular culture
In the Finnish video game series Angry Birds, the green toucan character Hal is given a long, massive beak with a boomerang-like structure that allows him to do something called "boomeranging", which is actually turning back in the direction towards the starting point.
References
Wikipedia Student Program
Toucans
Parts of a bird beak | Toco toucan beak | [
"Technology"
] | 2,841 | [
"Components",
"Parts of a bird beak"
] |
70,628,115 | https://en.wikipedia.org/wiki/Biofoam | Biofoams are biological or biologically derived foams, making up lightweight and porous cellular solids. A relatively new term, its use in academia began in the 1980s in relation to the scum that formed on activated sludge plants.
Biofoams is a broad umbrella term that covers a large variety of topics including naturally occurring foams, as well as foams produced from biological materials such as soy oil and cellulose. Biofoams have been a topic of continuous research because synthesized biofoams are being considered as alternatives to traditional petroleum-based foams. Due to the variable nature of synthesized foams, they can have a variety of characteristics and material properties that make them suitable for packaging, insulation, and other applications.
Naturally occurring foams
Foams can form naturally within a variety of living organisms. For example, wood, cork, and plant matter all can have foam components or structures. Fungi are generally composed of mycelium, which is made up of hollow filaments of chitin nanofibers bound to other components. Animal parts like cancellous bone, horseshoe crab shells, toucan beaks, sponge, coral, feathers, and antlers all contain foam-like structures which decrease overall weight at the expense of other material properties.
Structures like bone, antlers, and shells have strong materials housing weaker but lighter materials within. Bones tend to have compact, dense external regions, which protect the internal foam-like cancelous bone. The same principle applies to horseshoe crab shells, toucan beaks, and antlers. The barbs and shafts of feathers similarly contain closed-cell foam.
Protective foams can be formed externally by parent organisms or by eggs interacting with the environment: tunicate egg mix with sea water to create a liquid-based foam; tree frog eggs grow in protein foams above and on water (see Figure 1); certain freshwater fish lay eggs in surface foam from their mucus; deep sea fish produce eggs in swimbladders of dual layered foams; and some insects keep their larvae in foam.
Biomimetic synthetic foams
Honeycomb
Honeycomb refers to bioinspired patterns that provide a lightweight design for energy absorbing structures. Honeycomb design can be found in different structural biological components such as spongy bone and plant vasculature. Biologically inspired honeycomb structures include Kelvin, Weaire and Floret honeycomb (see Figure 2); each with a slightly different structure in comparison to the natural hexagonal honeycomb. These variations on the biological design have yielded significantly improved energy absorption results in comparison to traditional hexagonal honeycomb biofoam.
Due to these increased energy absorption performances, honeycomb inspired structures are being researched for use inside vehicle crumple zones. By using honeycomb structures as the inner core and surrounding the structure with a more rigid structural shell, these components can absorb impact energy during a crash and reduce the amount of energy the driver experiences.
Aerogel
Aerogels are able to fill large volumes with minimal material yielding special properties such as low density and low thermal conductivity. These aerogels tend to have internal structures categorized as open or closed cell structures, the same cell structure that is used to define many 3-dimensional honeycomb biofoams. Aerogels are also being engineered to mirror the internal foam structures of animal hairs (see Figure 3). These biomimetic aerogels are being actively researched for their promising elastic and insulative properties.
Material properties
Foam cell structures
A foam is considered open-celled if at least two of its facets are holes rather than walls. In this case the entirety of the load on the foam is on the cross-beams that make up the edges of the cell. If no more than one of the walls of the cell are holes, the foam is considered closed-celled in nature. For most synthetic foams, a mixture of closed cell and open cell character is observed due to cells rupturing during the foaming process and then the matrix solidifying.
The mechanical properties of the foam then depend on the closed cell character of the foam as derived by Gibson and Ashby:
Where E is the elastic modulus, ρ is the density of the material, φ is the ratio of the volume of the face to the volume of the edge of the material, and the subscript s denotes the bulk property of the material rather than that of the foam sample.
Liquid and solid foams
For many polymeric foams, a solidified foam is formed by polymerizing and foaming a liquid polymer mixture and then allowing that foam to solidify. Thus, liquid foam aging effects do occur before solidification. In the liquid foam, gravitational forces and internal pressures cause a flow of the liquid toward the bottom of the foam. This causes some of the foam cells to form into irregular polyhedra as liquid drains, which are less stable structures than the spherical structures of a traditional foam. These structures can however be stabilized by the presence of a surfactant.
The foam structure before solidification is an inherently unstable one, as the voids present greatly increase the surface free energy of the structure. In some synthetic biofoams, a surfactant can be used in order to lower the surface free energy of the foam and therefore stabilize the foam. In some natural biofoams, proteins can act as the surfactants for the foams to form and stabilize.
Fiber reinforcement
During the solidification of synthetic biofoams, fibers may be added as a reinforcement agent for the matrix. This additionally will create a heterogeneous nucleation site for the air pockets of the foam itself during the foaming process. However, as fiber content increases, it can begin to inhibit formation of the cellular structure of the matrix.
Applications
Packaging
In relation to packaging, starches and biopolyesters make up these biofoams as they are adequate replacements to expanded polystyrene. Polylactic acids (PLAs) are a common form of the basis of these biofoams since they offer a substitute for polyolefin-based foams that are commonly used in automotive parts, pharmaceutical products, and short life-time disposable packaging industries due to their bio-based and biodegradable properties. PLA comes from the formation of lactide produced from lactic acid due to bacterial fermentation through ring-opening polymerization, in which the process is shown through Figure 4.
PLA does not have the most desirable traits for biodegradability in the packaging industry as it contains a low heat distortion temperature and has unfavorable water barrier characteristics. On the other hand, PLA has been shown to have desirable packaging properties including high ultraviolet light barrier properties, and low melting and glass transition temperatures. As of recently, PGA has been introduced in the packaging industry as it is a good solvent and comparable to PLA. Table 1 shows the characteristics of both biofoams and how they compare. As shown, PGA contains a strong stereochemistry structure which in turn causes it to have high barrier and mechanical properties making it desirable for the packaging industry. The study of mixing both PGA and PLA has been explored by using copolymerization in order for PGA to help enhance the barrier properties of PLA when used in packaging.
Table 1: The properties of PLA in comparison to PGA.
Biomedical
The most popular biofoam in the use of biomedical devices is PLA as well. PLA's properties are also desirable in biomedical applications, especially in combination with other polymers. Specifically, its biocompatibility and biodegradability make it favorable in tissue engineering through the use of FDM-3D printing. PLA does well in these printing environments as its glass transition temperature as well as shape memory is small. In recent studies, PLA has been specifically combined with hydroxyapatite (HA) in order to make the modulus of the sample more favorable for its application in repairing bone failure. Specifically in tissue engineering, HA has also been shown to generate osteogenesis by triggering osteoblasts and pre-osteoblastic cells. HA is a strong material, which makes it ideal to add to PLA, due to the fact that PLA has weak toughness with a 10% elongation before failure. FFF-based 3D printing was used as well as compression tests demonstrated in Figure 5. The results showed that there was a self-healing capability of the sample, which could be used in certain biomedical practices.
Environmental impact
With recent attention toward climate change, global warming, and sustainability, there has been a new wave of research regarding the creation and sustainability of biodegradable products. This research has evolved to include the creation of biodegradable biofoams, with the intention to replace other foams that may be environmentally harmful or whose production may be unsustainable. Following this vein, Gunawan et al. conducted research to developed “commercially-relevant polyurethane products that can biodegrade in the natural environment”. One such product includes flip-flops so as part of the research a flip-flop made from algae derived polyurethane was prototyped (see Figure 7). This research ultimately resulted in the conclusion that in both a compost and soil environment (different microorganisms present in each environment) significant degradation occurs in polyurethane foam formulated from algae oil.
Similarly, research has been done where algae oil (AO) and residual palm oil (RPO) have been formulated into foam polyurethane at different ratios to determine what ratio has the optimum biodegradability. RPO is recovered from the waste of palm oil mill and is a byproduct of that manufacturing process. After undergoing a tests to determine biodegradability as well as a thermogravimetric analysis, the team determined that the material could be utilized in applications such as insulation or fire retardants depending on the AO/RPO ratio.
Another focus of biofoam research is the development of biofoams that are not only biodegradable, but are also cost-effective and require less energy to produce. Luo et al. have conducted research in this area of biofoams and have ultimately developed a biofoam that is produced from a “higher content of nature bioresource materials” and using a “minimal [number of] processing steps”. The processing steps include the one-pot method of foam preparation published by F. Zhang and X. Luo in their paper about developing polyurethane biofoams as an alternative to petroleum based foams for specific applications.
Ongoing research
Research efforts have been put into using natural components in the creation of potentially biodegradable foam products. Mycelium (Figure 8), chitosan (Figure 9), wheat gluten (Figure 10), and cellulose (Figure 11) have all been used to create biofoams for different purposes. The wheat gluten example was used in combination with graphene to attempt to make a conductive biofoam. The mycelium-based, chitosan-based, and cellulose-based biofoam examples are intended to become cost effective and low density material options.
References
Foams | Biofoam | [
"Chemistry"
] | 2,298 | [
"Foams"
] |
70,628,267 | https://en.wikipedia.org/wiki/Kahn%E2%80%93Kalai%20conjecture | The Kahn–Kalai conjecture, also known as the expectation threshold conjecture or more recently the Park-Pham Theorem, was a conjecture in the field of graph theory and statistical mechanics, proposed by Jeff Kahn and Gil Kalai in 2006. It was proven in a paper published in 2024.
Background
This conjecture concerns the general problem of estimating when phase transitions occur in systems. For example, in a random network with nodes, where each edge is included with probability , it is unlikely for the graph to contain a Hamiltonian cycle if is less than a threshold value , but highly likely if exceeds that threshold.
Threshold values are often difficult to calculate, but a lower bound for the threshold, the "expectation threshold", is generally easier to calculate. The Kahn–Kalai conjecture is that the two values are generally close together in a precisely defined way, namely that there is a universal constant for which the ratio between the two is less than where is the size of a largest minimal element of an increasing family of subsets of a power set.
Proof
Jinyoung Park and Huy Tuan Pham announced a proof of the conjecture in 2022; it was published in 2024.
References
See also
Percolation theory
Conjectures
21st century in mathematics
Graph theory
Statistical mechanics
2006 in science | Kahn–Kalai conjecture | [
"Physics",
"Mathematics"
] | 260 | [
"Unsolved problems in mathematics",
"Graph theory",
"Statements in graph theory",
"Conjectures",
"Mathematical relations",
"Statistical mechanics",
"Mathematical problems"
] |
58,130,041 | https://en.wikipedia.org/wiki/David%20Israel%20Schuster | David Israel Schuster is a chemist who is currently a professor emeritus at New York University. His research program focused on organic photochemistry and later on fullerenes.
Early life and education
Schuster was born in Brooklyn, New York in 1935 and raised in Far Rockaway. He attended Columbia University as an undergraduate and received his bachelor's degree in chemistry in 1956. He then moved to the California Institute of Technology, from which he received his Ph.D. in 1961 under the mentorship of John D. Roberts. During Schuster's time in the Roberts laboratory, the group began experimenting with some of the first applications of NMR spectroscopy to organic chemistry. Schuster next joined Howard Zimmerman's group at the University of Wisconsin as a postdoctoral fellow, where he spent a year studying mechanistic organic photochemistry.
Academic career
Schuster was recruited to New York University by Kurt Mislow, who was also interested in photochemistry, and joined the faculty there in late 1961 in what was at the time the University Heights, Bronx campus. He remained at NYU for his entire academic career. Schuster received tenure in 1968 and spent the 1968–69 academic year on sabbatical in London in the laboratory of George Porter. In 1974 NYU closed its Bronx campus, requiring Schuster to move his laboratory to the Manhattan campus near Washington Square Park. Among Schuster's influential advisees are structural biologist Dinshaw Patel and synthetic organic chemist Phil Baran, who worked in the laboratory as an NYU undergraduate. Schuster closed his laboratory and retired, assuming professor emeritus status, in 2010.
Schuster was elected a fellow of the American Association for the Advancement of Science in 1992 and received the Arthur C. Cope Scholar Award, given by the American Chemical Society, in 2012.
Personal life
Schuster married his wife Carlotta, a psychiatrist, in 1962. He is a lifelong classical music enthusiast and serious pianist.
References
1935 births
Living people
Photochemists
California Institute of Technology alumni
New York University faculty
Fellows of the American Association for the Advancement of Science | David Israel Schuster | [
"Chemistry"
] | 403 | [
"Photochemists",
"Physical chemists"
] |
58,130,085 | https://en.wikipedia.org/wiki/NGC%204237 | NGC 4237 is a flocculent spiral galaxy located about 60 million light-years away in the constellation Coma Berenices. The galaxy was discovered by astronomer William Herschel on December 30, 1783 and is a member of the Virgo Cluster. It is also classified as a LINER galaxy and as a Seyfert galaxy.
NGC 4237 appears to be deficient in neutral atomic hydrogen (H I). This, combined with its large projected distance from M87 and its radial velocity close to the Virgo Cluster mean suggests that the galaxy may be on a highly radial orbit through the center of the cluster.
Gallery
See also
List of NGC objects (4001–5000)
NGC 4212
References
External links
4237
39393
Coma Berenices
Virgo Cluster
Astronomical objects discovered in 1783
Flocculent spiral galaxies
7315
Seyfert galaxies
LINER galaxies | NGC 4237 | [
"Astronomy"
] | 179 | [
"Coma Berenices",
"Constellations"
] |
58,130,360 | https://en.wikipedia.org/wiki/Glyphosate-based%20herbicides | Glyphosate-based herbicides are herbicides made of a glyphosate salt usually combined with other ingredients needed to stabilize the formula and allow penetration into plants. Roundup was the first glyphosate-based herbicide, developed by Monsanto in the 1970s. It is used most heavily on corn, soy, and cotton crops that have been genetically modified to be resistant to the herbicide. Some products include two active ingredients, such as Enlist Duo which includes 2,4-D as well as glyphosate. As of 2010, more than 750 glyphosate products were on the market. The names of inert ingredients used in glyphosate formulations are usually not listed on the product labels.
Glyphosate and glyphosate-based herbicides have low acute toxicity in mammals. They likewise have not been shown to pose a significant risk to human health during normal use, although human deaths have been reported from deliberate ingestion of concentrated RoundUp. It is difficult to determine how much surfactants contribute to the overall toxicity of each formulation. Glyphosate formulations containing the surfactant polyethoxylated tallow amine (POEA) are sometimes used terrestrially, but are not approved for aquatic use in the US due to their toxicity to aquatic organisms.
There have been multiple lawsuits against Monsanto asserting that exposure to glyphosate herbicides is carcinogenic and that the company did not adequately disclose the risk to consumers. In 2018 a California jury awarded $289 million in damages (later cut to $78 million on appeal then reduced to $21 million after another appeal) to a groundskeeper who argued that Monsanto failed to adequately warn consumers of cancer risks posed by the herbicides.
Background
The glyphosate-based herbicide RoundUp (styled: Roundup) was developed in the 1970s by Monsanto. Glyphosate was first registered for use in the U.S. in 1974. Glyphosate-based herbicides were initially used in a similar way to paraquat and diquat, as non-selective herbicides. Attempts were made to apply them to row crops, but problems with crop damage kept glyphosate-based herbicides from being widely used for this purpose. In the US, use of glyphosate experienced rapid growth following the commercial introduction of a glyphosate-resistant soybean in 1996. Between 1990 and 1996 sales of RoundUp increased around 20% per year. it is used in over 160 countries. RoundUp is used most heavily on corn, soy, and cotton crops that have been genetically modified to withstand the chemical, but since 2012 glyphosate was used in California to treat other crops like almond, peach, cantaloupe, onion, cherry, sweet corn, and citrus.
Bayer, which acquired Monsanto in 2018, is the largest producer of glyphosate-based herbicides, but formulations from other manufacturers are available that use different inert ingredients. Other glyphosate-based formulations include Bronco, Glifonox, KleenUp, Ranger Pro (styled: Ranger PRO), Rodeo, and Weedoff. Other manufacturers include Anhui Huaxing Chemical Industry Company, BASF, Dow AgroSciences, DuPont, Jiangsu Good Harvest-Weien Agrochemical Company, Nantong Jiangshan Agrochemical & Chemicals Co., Nufarm, SinoHarvest, Syngenta, and Zhejiang Xinan Chemical Industrial Group Company. As of 2010, more than 750 glyphosate products were on the market.
Inert ingredients
Surfactants, solvents, and preservatives are inert ingredients, or adjuvants, that are commonly added to glyphosate-based herbicide formulations. Some products contain all the necessary adjuvants, including surfactant; some contain no adjuvant system, while other products contain only a limited amount of adjuvant. Some formulations require the addition of surfactants to the spray tank before application. The names of inert ingredients used in glyphosate formulations are usually not listed on the product labels.
Polyethoxylated tallow amine (POEA) is a surfactant added to Roundup and other herbicides as a wetting agent. POEA is not a single surfactant, but a complex mixture. The composition of each POEA surfactant is a proprietary trade secret. Monsanto's RoundUp, for example, contains a proprietary POEA surfactant called MON 0818 at a 15% concentration.
Regulatory history
European Union
As part of the process to renew glyphosate's license under EU regulations, a 2013 systematic review by the German Federal Institute for Risk Assessment (Bfr) of epidemiological studies of workers exposed to glyphosate formulations found no significant risk, stating that "the available data are contradictory and far from being convincing". In 2015, as part of the ongoing renewal process, the European Food Safety Authority (EFSA) published a final risk assessment on 12 November 2015 stating that glyphosate met EU-level regulatory standards. Despite classifying glyphosate as non-carcinogenic, this report also acknowledged that some of the co-formulants added to glyphosate based pesticides "appeared to have toxic effects higher than the glyphosate itself", noting POEA in particular. The conclusion of the final EFSA assessment was that the active ingredient glyphosate met EU-level regulatory standards, but individual formulations would have to be evaluated by member states.
There was insufficient support among the Member States for a 2016 European Commission proposal to renew the approval of glyphosate. Because the 2015 EFSA and IARC assessments had reached contradictory conclusions regarding the potential carcinogenicity of glyphosate, the European Chemicals Agency (ECHA) was asked to assess the hazard properties of the substance. Though no majority of Member States voted either for or against the renewal proposal, in July 2016 they voted to amend the conditions of glyphosate's existing approval. The new conditions require Member States to minimize the pre-harvest use of glyphosate products, as well as use in certain public places. Formulations that include the surfactant POEA were banned. These conditions were later included in the implementing act for the 5-year renewal that was approved on 12 December 2017.
United States
In 2014 the EPA approved Enlist Duo, which was developed by Dow AgroSciences. This herbicide combined two active ingredients: 2,4-D and glyphosate. Enlist Duo is intended for use with genetically modified crops that have also been developed by the Dow Chemical subsidiary. The initial approval was limited to the states of Illinois, Indiana, Iowa, Ohio, South Dakota, and Wisconsin. During the course of litigation in 2015, the EPA found out that Dow had told the United States Patent and Trademark Office that Enlist Duo offers "synergistic herbicidal weed control", and requested additional clarification about the "synergistic effects" and sought to reverse its approval pending a full review of the new information provided by Dow. In 2016, the 9th Circuit rejected the EPA's petition to vacate its approval of the herbicide.
Since some glyphosate herbicide formulations contain an inert ingredient that may be toxic to fish and amphibians, only formulations labeled for aquatic use are recommended when water contamination is possible. Aquatic formulations using the isopropylamine salt of glyphosate include Glypro (also called Rodeo, Aquapro, and Accord Concentrate) and Shore-Klear. Refuge is also approved for aquatic applications; the active ingredient in this formulation is the potassium salt of glyphosate. There are a few aquatic formulations that already include a surfactant that are registered for aquatic applications including GlyphoMate41 and Shore-Klear Plus, but most aquatic formulations do not include surfactant. The composition of surfactants is proprietary and non-disclosed, but low-toxicity surfactants that are labeled for aquatic use are available.
Legal
On 10 August 2018, Dewayne "Lee" Johnson, who has non-Hodgkin's lymphoma, was awarded $289 million in damages in the case Johnson v. Monsanto Co. (later cut to $78 million on appeal then reduced to $21 million after another appeal) after a jury in San Francisco found that Monsanto had failed to adequately warn consumers of cancer risks posed by the herbicide. Johnson had routinely used two different glyphosate formulations in his work as a groundskeeper, RoundUp and another Monsanto product called Ranger Pro. The jury's verdict addressed the question of whether Monsanto knowingly failed to warn consumers that RoundUp could be harmful, but not whether RoundUp causes cancer. Court documents from the case show the company's efforts to influence scientific research via ghostwriting. After the IARC classified glyphosate as a "probably carcinogenic to humans" in 2015, over 300 federal lawsuits have been filed that were consolidated into a multidistrict litigation called In re: RoundUp Products Liability.
In March 2019, a man was awarded $80 million in a lawsuit claiming Roundup was a substantial factor in his cancer, resulting in Costco stores discontinuing sales. In July 2019, U.S. District Judge Vince Chhabria reduced the settlement to $26 million. Chhabria stated that a punative award was appropriate because the evidence "easily supported a conclusion that Monsanto was more concerned with tamping down safety inquiries and manipulating public opinion than it was with ensuring its product is safe." Chhabria stated that there is evidence is on both sides concerning whether glyphosate causes cancer and that the behavior of Monsanto showed "a lack of concern about the risk that its product might be carcinogenic."
On 13 May 2019 a jury in California ordered Bayer to pay a couple $2 billion in damages after finding that the company had failed to adequately inform consumers of the possible carcinogenicity of Roundup. On July 26, 2019, an Alameda County judge cut the settlement to $86.7 million, stating that the judgement by the jury exceeded legal precedent.
In June 2020, Bayer agreed to settle over a hundred thousand Roundup lawsuits, agreeing to pay $8.8 to $9.6 billion to settle those claims, and $1.5 billion for any future claims. The settlement does not include three cases that have already gone to jury trials and are being appealed.
Acute toxicity
The lethal dose of different glyphosate-based formulations varies, especially with respect to the surfactants used. Formulations intended for terrestrial use that include the surfactant polyethoxylated tallow amine (POEA) can be more toxic than other formulations for aquatic species. Due to the variety in available formulations, including five different glyphosate salts and different combinations of inert ingredients, it is difficult to determine how much surfactants contribute to the overall toxicity of each formulation. Independent scientific reviews and regulatory agencies have regularly concluded that glyphosate-based herbicides do not lead to a significant risk for human or environmental health when the product label is properly followed.
Human
The acute oral toxicity for mammals is low, but death has been reported after deliberate overdose of concentrated formulations. The surfactants in glyphosate formulations can increase the relative acute toxicity of the formulation. Surfactants generally do not, however, cause synergistic effects (as opposed to additive effects) that increase the acute toxicity of glyphosate within a formulation. The surfactant POEA is not considered an acute toxicity hazard, and has an oral toxicity similar to vitamin A and less toxic than aspirin. Deliberate ingestion of Roundup ranging from 85 to 200 mL (of 41% solution) has resulted in death within hours of ingestion, although it has also been ingested in quantities as large as 500 mL with only mild or moderate symptoms. Consumption of over 85 mL of concentrated product causes serious symptoms, including burns due to corrosive effects as well as kidney and liver damage.
Forest visitors and nearby residents could be exposed to herbicide drift, vegetation with herbicide residues, and to accidental spraying. They also could eat food or drink water containing herbicide residues.
In a 2017 risk assessment, the European Chemicals Agency (ECHA) wrote: "There is very limited information on skin irritation in humans. Where skin irritation has been reported, it is unclear whether it is related to glyphosate or co-formulants in glyphosate-containing herbicide formulations." The ECHA concluded that available human data was insufficient to support classification for skin corrosion or irritation.
Inhalation is typically less harmful, though mist particles can result in irritation within the mouth or nostrils. Minor conjunctivitis can occur from eye exposure, and damage to the cornea can develop if the eye is not thoroughly rinsed after exposure.
Aquatic
Glyphosate products for aquatic use generally do not use surfactants, and formulations with POEA are not approved for aquatic use due to aquatic organism toxicity. Due to the presence of POEA, glyphosate formulations only allowed for terrestrial use are more toxic for amphibians and fish than glyphosate alone. Terrestrial glyphosate formulations that include the surfactants POEA and MON 0818 (75% POEA) may have negative impacts on various aquatic organisms like protozoa, mussels, crustaceans, frogs and fish. Aquatic organism exposure risk to terrestrial formulations with POEA may occur due to drift, agricultural runoff or temporary water pockets. While laboratory studies can show effects of glyphosate formulations on aquatic organisms, similar observations rarely occur in the field when instructions on the herbicide label are followed.
Studies in a variety of amphibians have shown the toxicity of GBFs containing POEA to amphibian larvae. These effects include interference with gill morphology and mortality from either the loss of osmotic stability or asphyxiation. At sub-lethal concentrations, exposure to POEA or glyphosate/POEA formulations has been associated with delayed development, accelerated development, reduced size at metamorphosis, developmental malformations of the tail, mouth, eye and head, histological indications of intersex and symptoms of oxidative stress. Glyphosate-based formulations can cause oxidative stress in bullfrog tadpoles. The use of glyphosate-based pesticides are not considered the major cause of amphibian decline, the bulk of which occurred prior to widespread use of glyphosate or in pristine tropical areas with minimal glyphosate exposure.
Mammals
Pure chemical grade glyphosate is slightly toxic to birds and is virtually nontoxic to fish, aquatic invertebrates and honeybees. However, commercial herbicide formulations consist of combinations of glyphosate salts, adjuvants and surfactants, and are not tested as such prior to regulatory approval. Due to the presence of a toxic inert ingredient, some glyphosate end-use products must be labeled, "Toxic to fish," if they may be applied directly to aquatic environments. In mammals, most glyphosate is excreted, unchanged, in urine and feces. In rats, Glyphosate was not broken down given in oral doses, and it did not bioaccumulate.
Sub-lethal effects
Most regulatory studies require only short-term exposure to high levels of the regulated substance, and do not investigate the effects of long-term exposure to sub-lethal levels. There is now increasing concern that chronic exposure to sub-lethal levels of glyphosate based herbicides may be having severe effects on ecosystem, animal and human health, especially when considering the possibility of synergistic effects with other chemicals also present in the environment.
Laboratory animal research reveals potential impacts on reproduction, carcinogenesis and even multigenerational and transgenerational effects, due to epigenetic changes. Trangenerational studies showed dramatic effects on fertility, neurological development, prostate disease, obesity, kidney disease, ovarian disease, and parturition (birth) abnormalities in the grand offspring (F2) and great-grand-offspring (F3) of mothers exposed to glyphosate.
Biomonitoring studies suggest that humans in a non-agricultural setting may be exposed to glyphosate through drinking water and by eating products derived from crops contaminated with this herbicide, especially as glyphosate has been shown to accumulate in plant tissues to levels much higher than present in the environment. Significant glyphosate residues have been detected in multiple crops, including honey, corn, wheat and soy products.
A 2018 study in central Indiana found that > 90% of pregnant women had detectable urinary glyphosate levels and that these levels correlated significantly with shortened pregnancy lengths.
Glyphosate exposure has also been implicated as a contributing factor in the development of chronic kidney disease in agricultural workers.
Carcinogenicity of active ingredient
There is limited evidence human cancer risk might increase as a result of occupational exposure to large amounts of glyphosate, such as agricultural work, but no good evidence of such a risk from home use, such as in domestic gardening. The consensus among national pesticide regulatory agencies and scientific organizations is that labeled uses of glyphosate have demonstrated no evidence of human carcinogenicity. Organizations such as the Joint FAO/WHO Meeting on Pesticide Residues, European Commission, Canadian Pest Management Regulatory Agency, and the German Federal Institute for Risk Assessment have concluded that there is no evidence that glyphosate poses a carcinogenic or genotoxic risk to humans. The final assessment of the Australian Pesticides and Veterinary Medicines Authority in 2017 was that "glyphosate does not pose a carcinogenic risk to humans". In a draft document the EPA has classified glyphosate as "not likely to be carcinogenic to humans." One international scientific organization, the International Agency for Research on Cancer (IARC), affiliated with the WHO, has made claims of carcinogenicity in research reviews; in 2015 the IARC declared glyphosate "probably carcinogenic to humans."
Environmental impact
Due to the widespread cultivation of crop species designed to withstand herbicide application, a move towards no-till agriculture, and weeds developing glyphosate resistance, increasing amounts of glyphosate-based herbicides are now required for weed control globally. This widespread and increasing use is leading to the detection of glyphosate in surface waters, sediment and soil across South America, North America, Europe, Asia and Africa, sometimes at levels above regulatory limits. However, regulatory limits vary immensely across jurisdictions. For example, maximum allowable drinking water levels in Europe are set at 100 ng/L while the Environmental Protection Agency in the USA allows up to 700 ug/L glyphosate in American drinking water, while in many countries allowable levels of glyphosate in the environment and drinking water are not regulated at all.
In crops and other plants, there is evidence that glyphosate exposure can lead to increased susceptibility to disease, especially fungal root rot, and changes in mineral nutrition.
On a wider front, there is the added concern that the widespread agricultural use of glyphosate may be contributing to antibiotic resistance and changes in soil and other microbiomes, as this herbicide is known to act as an antibiotic and affects microbial and fungal communities.
As mentioned before, glyphosate-based herbicides can be harmful to freshwater and marine aquatic life, affecting invertebrates, amphibians and fish especially in their juvenile life stages. Lately, research has focused on what happens when organisms are exposed to low levels of herbicide over longer time periods, at levels detected during environmental monitoring. The results suggest a level of concern is warranted - exposure to environmentally realistic levels of glyphosate based herbicides (10 ug/L to 20 ug/L) have been shown to negatively affect blood parameters of the mussel Mytilus galloprovincialis and the clam Ruditapes philippinarum, as well as decreasing reproduction and growth of the estuarine crab Neohelice granulata.
Glyphosate based herbicides may be leading to overgrowth of blue-green algae in freshwater bodies, while levels as low as 1 ug/L can lead to total loss of recruitment in the canopy forming marine macroalga, Carpodesmia crinita potentially leading to population collapse. Glyphosate exposure can also alter the structure of natural freshwater bacterial and zooplankton communities. Researchers found that for zooplankton, aquatic concentrations of 0.1 mg/L glyphosate were sufficient to cause diversity loss. These effects on organisms at the base of the food chain may have long term unintended effects.
Glyphosate is also being detected in wildlife, with long term effects unknown. For example a study published in 2021 detected glyphosate in 55% of sampled Florida manatees’ plasma, with blood levels increasing significantly from 2009 until 2019. In the same study, glyphosate was ubiquitous in surface water samples.
Supply chain issues
Between January and November 2021, the price of glyphosate rose 25 percent due to the effects of the 2021–2022 global supply chain crisis and COVID-19. In February 2022, Bayer AG announced they would be declaring a force majeure following a mechanical failure and production shutdown at a key supplier. Shortages were expected to lead to increased costs for cotton, soybean and corn producers.
References
Herbicides
Agricultural terminology
History of agriculture | Glyphosate-based herbicides | [
"Biology"
] | 4,615 | [
"Herbicides",
"Biocides"
] |
58,130,936 | https://en.wikipedia.org/wiki/Coniferous%20resin%20salve | Spruce resin salve is a traditional wound treatment method that has gained new popularity again after clinical studies in the 21st century. The pure coniferous resin from Norway spruce is antimicrobial against a wide range of bacteria and fungi and positively associates with progressive healing of the wound. The improvement is not limited to the healing of the infected wounds only, suggesting that the resin has positive influences on mechanisms that play a role in wound repair.
History
The first reports of using resins or rosins in medicine are from antiquity. Resins have been used for nearly every kind of human disorder and disease. First medical publication of the use of coniferous resin in medical practice in Finland is from 1578. Swedish physician Benedictus Olai wrote about natural resin in treatment of old leg wounds in the first medical textbook of the Swedish kingdom.
Elias Lönnrot presented the first recipe for resin salve in the Flora Fennica book 1866.
Biological effects
Natural resin is a complex composition of components such as resin acids, lignans and coumaric acid. The levels of these components are dependent on what type of coniferous tree resin it is and when it is collected i.e. fresh physiological resin or matured resin collected from trunk of the tree
In vitro studies have shown that natural resin is strongly antimicrobial against a broad spectrum of common bacteria, fungi and yeasts. The antimicrobial effect is based on resin acid that breaks down the cell wall and the cell membrane and because of that the cell can no longer produce energy and eventually it dies. Microbiological studies have proven that resin is also effective on antibiotic resistant microbes (MRSA & VRE). Spruce resin affects both gram positive and gram negative bacteria.
Reducing the bacterial and fungal contamination of the wound is generally known to improve the wound healing.
In clinical tests, (Abilar 10%®) Resin salve has shown to improve wound healing and reduce pain on various wounds including pressure ulcers, complicated surgical wounds and diabetic foot ulcers.
Contra indications
Persons allergic to resin acids should not use these types of product since it may cause them to develop a topical skin rash. One unselected general population study of 793 Danish adults in 1992 shows a prevalence of colophony allergy of 0.4% in men and 1.0% in women.
References
Traditional medicine
Resins
Conifers | Coniferous resin salve | [
"Physics"
] | 486 | [
"Amorphous solids",
"Unsolved problems in physics",
"Resins"
] |
58,131,299 | https://en.wikipedia.org/wiki/Ramon%20E.%20Moore | Ramon Edgar (Ray) Moore ( ) was an American mathematician, known for his pioneering work in the field of interval arithmetic.
Moore received an AB degree in physics from the University of California, Berkeley in 1950, and a PhD in mathematics from Stanford University in 1963. His early career included work on the earliest computers (including ENIAC). He was awarded the Humboldt Research Award for U.S. senior scientists twice, in 1975 and 1980.
His most well known work is his first book, Interval Analysis, published in 1966. He wrote several more books and many journal articles and technical reports.
R. E. Moore Prize
The R. E. Moore Prize for Applications of Interval Analysis is an award in the interdisciplinary field of rigorous numerics. It is awarded biennially by the Computer Science Department at the University of Texas at El Paso, and judged by the editorial board of the journal Reliable Computing. The award was named in honor of Moore's contributions to interval analysis.
Laureates
See also
List of mathematics awards
References
Further reading
External links
Faculty webpage
R. E. Moore Prize
20th-century American mathematicians
Mathematics awards
Stanford University alumni
University of California, Berkeley alumni
University of Texas at El Paso faculty
1929 births
2015 deaths
21st-century American mathematicians | Ramon E. Moore | [
"Technology"
] | 252 | [
"Science and technology awards",
"Mathematics awards"
] |
58,132,409 | https://en.wikipedia.org/wiki/Lipozyme | Lipozyme, a registered trademark of Novo Nordisk A/S Corp., is a class of industrial enzymes, specifically: lipases.
Lipozymes can be differentiated by origin - it can be extracted from Mucor miehei, Thermomyces lanuginosus, Candida antarctica, and others. For industrial purposes, it can be immobilized on macroporous ion-exchange resins. Lipases like Lipozyme and Novozyme (reg.trademark by Novozymes) play a big role in the synthesis of biodiesel. Lipozyme is also offered as a food supplement clad in capsules. It comes in different activities, measured e.g. in IUN/g or KLU/g (IUN = Interesterification Unit, K = Kilo, LU = Lipase unit).
References
Industrial enzymes | Lipozyme | [
"Biology"
] | 182 | [
"Industrial enzymes"
] |
58,132,772 | https://en.wikipedia.org/wiki/Ethics%20Matters | The Ethics Matters is a TV series on applied ethics and political philosophy, aired on ABC television in Australia. All episodes are also available online. The series was awarded the Media Prize of the Australasian Association of Philosophy in 2018.
Production
Presenter: Dan Halliday
Podcast Co-Presenter: Christian Barry
Director: Catherine Gough-Brady
Essayist: Brigid Evans
Producer: Snodger Media
References
External links
Ethics Matters
2010s Australian television series
Philosophy television series
Australian Broadcasting Corporation original programming
Applied ethics
Political philosophy | Ethics Matters | [
"Biology"
] | 102 | [
"Behavior",
"Human behavior",
"Applied ethics"
] |
58,134,314 | https://en.wikipedia.org/wiki/Maurice%20Brodie | Maurice Brodie (1903–1939) was a British-born American virologist who developed a polio vaccine in 1935.
Early years and education
Brodie was born in Liverpool, England, the son of Samuel Broude and Esther Ginsburg. The family immigrated to Ottawa, Canada, in 1910. Maurice graduated from Lisgar Collegiate Institute and McGill University Faculty of Medicine, Alpha Omega Alpha, in 1928; he was named a Wood Gold Medalist. He served as a medical intern, and in 1931 he received a Master of Science degree in physiology from McGill. Brodie belonged to the McGill chapter of Sigma Alpha Mu, and had been a staff reporter of the Ottawa Citizen, 1927–1928.<ref>Dr. Maurice Brodie dies in Detroit. The Gazette (Montreal). 12 May 1939</ref> At McGill 1932 he received a grant from the Banting Research Foundation for his studies of polio.
Polio research
Maurice Brodie joined the New York City Health Department and the bacteriology department at New York University Medical College.
In 1935, Brodie demonstrated induction of immunity in monkeys with inactivated polio virus. Isabel Morgan demonstrated the same phenomenon again a decade later.
Brodie was head of one of two separate teams that developed polio vaccines and reported their results at the annual meeting of the American Public Health Association in November 1935. Both projects were cancelled as a result of complications from vaccine trials resulting in the death of 6 participants and the paralysis of 10 others. The resulting public outrage delayed further research on the polio vaccine until the 1950s, when the Salk and Sabin vaccines were produced.
John Kolmer, of Temple University in Philadelphia, presented his findings first. He had developed an attenuated poliovirus vaccine, which he tested in about 10,000 children across much of the United States and Canada. Five of these children died of polio and 10 more were paralyzed, usually in the arm where the vaccine was injected, and frequently affecting children in towns where no polio outbreak had occurred. He had no control group, but asserted that many more children would have gotten sick. The response from other researchers was uncharacteristically blunt; one of them directly called Kolmer a murderer.
Brodie presented his results afterwards, but the feelings of the researchers were already unfavorable before he started because of Kolmer's report. Brodie and his team had prepared a formaldehyde-killed poliovirus vaccine, testing it first on Brodie himself and five co-workers, and eventually on 7,000 children and adults, with another 4,500 people serving as a control group. In the control group, Brodie reported that five out of 4500 developed polio; in the group receiving the vaccine, one out of 7,000 developed polio. This difference is not quite statistically significant, and other researchers believed that the one case was likely caused by the vaccine. Two more possible cases were reported later.
Rockefeller Institute Virologist Thomas Rivers declared that Brodie's vaccine was ineffective, while the safety of Kolmer’s vaccine was in doubt. Dr William Hallock Park, director of the New York City Health Department Research Laboratories, thereupon decided to discontinue development of Brodie's vaccine, which he had sponsored. But some experts felt Brodie's vaccine deserved further study; the case against it was inconclusive and too hastily drawn.
Later career
In 1936, Brodie moved to Detroit, where he became director of laboratories at Providence Hospital and hospital pathologist. He died suddenly while working in his laboratory, 3:45 pm, Tuesday, May 9, 1939. Cause of death was coronary thrombosis. His remains were sent to Ottawa for burial.Burial in Ottawa for Dr. Brodie. Detroit Times Thursday, May 11, 1939 Detroit, MI Page: 3 He was interred in the Jewish Cemetery on Metcalfe Road (now the Jewish Memorial Gardens on Bank Street) in Ottawa.Maurice Brodie, noted scientist, passes at Detroit. Ottawa Citizen 10 May 1939 p1.
Family
Maurice Brodie was a brother of Bernard Beryl Brodie (7 August 1907 – 28 February 1989), a leading researcher on drug therapy.
References
Further reading
Steven Lehrer. Explorers of the Body''. Doubleday 1979, 2006.
1903 births
1939 deaths
American medical researchers
American virologists
New York University faculty
Polio
Vaccinologists
Medical doctors from Liverpool
McGill University Faculty of Medicine alumni
New York University Grossman School of Medicine faculty
Lisgar Collegiate Institute alumni
Health professionals from Merseyside
English emigrants to the United States
English expatriates in Canada | Maurice Brodie | [
"Biology"
] | 927 | [
"Vaccination",
"Vaccinologists"
] |
58,138,832 | https://en.wikipedia.org/wiki/Nadir%20and%20Occultation%20for%20Mars%20Discovery | Nadir and Occultation for MArs Discovery (NOMAD) is a 3-channel spectrometer on board the ExoMars Trace Gas Orbiter (TGO) launched to Mars orbit on 14 March 2016.
NOMAD is designed to perform high-sensitivity orbital identification of atmospheric components, concentration and temperature, their sources, loss, and cycles. It measures the sunlight reflected from the surface and atmosphere of Mars, and it analyses its wavelength spectrum to identify the components of the Martian atmosphere that may suggest a biological source. The Principal Investigator is Ann Carine Vandaele, from the Belgian Institute for Space Aeronomy, Belgium.
Overview
NOMAD is one of four science instruments on board the European ExoMars TGO orbiter. This spectrometer consists of three separate channels: solar occultation (SO), limb nadir and occultation (LNO), and ultraviolet and visible spectrometer (UVIS). The first two channels work in the infrared (2.2 to 4.3 μm); the third channel (UVIS) works in the UV-visible range (0.2 to 0.65 μm), which is able to measure ozone, sulphuric acid, and perform aerosol studies. Measurements are carried out during solar occultation, i.e. the instrument points toward the sunset as the orbiter moves toward or away the dark side of Mars. It also measures in nadir mode, i.e. looking directly at the sunlight reflected from the surface and atmosphere of Mars.
Since 9 April 2018, NOMAD is measuring the existing atmospheric concentrations of gases, their temperature and total densities. Atmospheric methane concentrations below 1 ppb can be detected. These measurements will also facilitate investigations in the production and loss processes for the cycles of water, carbon, and dust.
NOMAD development and fabrication was carried out by OIP Sensor Systems at Belgium, in collaboration with partners in Spain, the United Kingdom, Italy, US, and Canada. Its development was based on the SPICAV spectrometer flown on Venus Express.
Objectives
NOMAD will map the composition and distribution of Mars' atmospheric trace gases and isotopes in unprecedented detail. The specific objectives are:
search for signs of past or present life on Mars.
investigate how the water and geochemical environment varies
investigate Martian atmospheric trace gases and their sources.
study the surface environment and identify hazards to future crewed missions to Mars.
investigate the planet subsurface and deep interior to better understand the evolution and habitability of Mars.
To achieve these objectives, NOMAD covers a spectral region from UV, visible, and infrared that reveals the signatures of the following molecules and isotopologues:
CO2 (including 13CO2, 17OCO, 18OCO, C18O2), CO (including 13CO, C18O), H2O (including HDO), NO2, N2O, O3, CH4 (including 13CH4, CH3D), C2H2, C2H4, C2H6, H2CO, HCN, OCS, SO2, HCl, HO2, and H2S.
In particular, the detection of the different methane (CH4) isotopologues (13CH4, CH3D) will be key to help determine whether they are of geological (serpentinisation, clathrates) or a biological source. In addition, NOMAD can detect formaldehyde () which is a photochemical product of methane, as well as nitrous oxide () and hydrogen sulfide () which are potential atmospheric biosignatures. SO2, a gas related to volcanism may reveal present or recent volcanic activity on Mars.
See also
Astrobiology
Compact Reconnaissance Imaging Spectrometer for Mars, a spectrometer on the Mars Reconnaissance Orbiter
ExoMars programme
Jovian Infrared Auroral Mapper, a spectrometer aboard Juno Jupiter orbiter
Life on Mars
Martian atmosphere
Water on Mars
References
ExoMars
Spacecraft instruments
Astrobiology
Space science experiments | Nadir and Occultation for Mars Discovery | [
"Astronomy",
"Biology"
] | 821 | [
"Origin of life",
"Speculative evolution",
"Astrobiology",
"Biological hypotheses",
"Astronomical sub-disciplines"
] |
58,139,364 | https://en.wikipedia.org/wiki/Nira%20Dyn | Nira (Richter) Dyn (; born 1942) is an Israeli mathematician who studied geometric modeling, subdivision surfaces, approximation theory, and image compression. She is a professor emeritus of applied mathematics at Tel Aviv University, and has been called a "pioneer and leading researcher in the subdivision community".
Education and career
Dyn earned a bachelor's degree from the Technion – Israel Institute of Technology in 1965. She went on to graduate study at the Weizmann Institute of Science, where she earned a master's degree in 1967 and completed her doctorate in 1970.
Her dissertation, Optimal and Minimum Norm Approximations to Linear Functionals in Hilbert Spaces, and their application to Numerical Integration, was supervised by Philip Rabinowitz.
After postdoctoral research in the Institute of Fundamental Studies at the University of Rochester, she joined the Tel Aviv faculty in 1972, and retired in 2010.
Recognition
Dyn was an invited speaker at the 2006 International Congress of Mathematicians, in the section on numerical analysis and scientific computing.
Books
Dyn is the author of:
Stochastic Models in Biology (as Nira Richter-Dyn, with Narendra S. Goel, Academic Press, 1974)
Approximation of Set-valued Functions: Adaptation of Classical Approximation Operators (with Elza Farkhi and Alona Mokhov, Imperial College Press, 2014)
References
External links
Home page
Living people
Israeli mathematicians
Israeli women mathematicians
Technion – Israel Institute of Technology alumni
Weizmann Institute of Science alumni
Academic staff of Tel Aviv University
1942 births
Applied mathematicians | Nira Dyn | [
"Mathematics"
] | 310 | [
"Applied mathematics",
"Applied mathematicians"
] |
58,142,968 | https://en.wikipedia.org/wiki/Samsung%20Gear%20Sport | The Samsung Gear Sport is a smartwatch developed by Samsung Electronics. The Gear Sport was released at Samsung Galaxy Unpacked in 2017.
Specifications
References
Products introduced in 2017
Smartwatches
Samsung wearable devices | Samsung Gear Sport | [
"Technology"
] | 42 | [
"Smartwatches"
] |
58,143,356 | https://en.wikipedia.org/wiki/ODK%20%28software%29 | ODK is an open-source mobile data collection platform. It enables users to fill out forms offline and send form data to a server when a connection is found. Once on the server, the data can be viewed, downloaded, and acted upon.
ODK is primarily used by organizations working in humanitarian aid and global development. Notable users include World Health Organization, International Red Cross and Red Crescent, and Carter Center. ODK has been recognized by the Digital Public Goods Alliance as a digital public good.
History
ODK (formerly called Open Data Kit) was founded in 2008 by Gaetano Borriello, Yaw Anokwa, Waylon Brunette, and Carl Hartung. It was designed to be an extensible, open-source suite to build information services for developing regions.
References
External links
ODK website
Data collection
Cross-platform free software
Free software programmed in Java (programming language)
Software using the Apache license | ODK (software) | [
"Technology"
] | 193 | [
"Data collection",
"Data"
] |
58,143,468 | https://en.wikipedia.org/wiki/Basic%20Space%20Law | The , is a Japanese space law that governs space-related activities.
References
Space law | Basic Space Law | [
"Astronomy"
] | 20 | [
"Space law",
"Outer space"
] |
58,144,386 | https://en.wikipedia.org/wiki/Jessica%20Polka | Jessica Polka is a biochemist and the Executive Director of ASAPbio (Accelerating Science and Publication in biology), a non-profit initiative promoting innovation and transparency via preprints and open peer review. She was one of the organizers of a recent meeting they held on scholarly communication.
Education
Polka received a BS in biology from the University of North Carolina at Chapel Hill in 2007. While there, she was a Morehead Scholar. She obtained a Ph.D. in biochemistry from the University of California, San Francisco under the supervision of Dyche Mullins in 2012.
Career
In 2013 Polka became a research fellow in the department of Systems Biology at Harvard Medical School with Pamela Silver as advisor. She was also held a visiting scholar at the Whitehead Institute in Massachusetts. Polka conducted research in the assembly, function, and applications of protein polymers in bacteria, such as membrane-breaking protein needles called R bodies. Polka's work on R bodies was discussed in the American magazine The Atlantic, and covered by the American Chemical Society. Polka discovered that carboxysome, a protein organelle in cyanobacteria, grows like a crystal until it is coated by a layer of shell proteins.
Polka was co-chair of the American Society for Cell Biology's COMPASS (Committee for Postdocs and Students) during 2013 and 2014.
Improving research culture
Polka is on the steering committee for Rescuing Biomedical Research, an initiative to discuss solutions to problems addressed in the April 2014 PNAS article "Rescuing US biomedical research from its systemic flaws".
Polka is recognised as having insight into issues surrounding open peer review, preprint and early career progression, and has been quoted in numerous articles by Nature and Science on these topics. In 2015, Polka and Viviane Callier wrote an article for the careers column in Nature where they argue that funding agencies should support more than 16% of postdocs through fellowships. This would allow postdocs to "strike out away from the beaten path [and] will bring fresh ideas and approaches to the table".
Future of Research
Polka was one of the organisers of the first Future of Research Symposium in Boston in 2014. She was on the executive committee until she became president of the board of directors in 2016. Polka is involved in creating debate amongst early-career scientists about the financial, historical and political influences on academic research. Future of Research was awarded the People of the Year award in 2015 by Science journal for their "efforts to empower early-career and aspiring scientists...".
ASAPbio
Polka was a founder of ASAPbio which began in 2015 after Ron Vale showed that University of California, San Francisco students were taking a long time to publish and proposed that preprinting might mitigate the issue. Vale recruited Polka, Daniel Colon-Ramos and Harold Varmus which led to the first ASAPbio meeting in February 2016 attended by scientists, representatives from funding agencies, journals and preprint servers. The meeting Polka led was widely recognized as a turning point in scholarly communication and a catalyst moment in the so-called "preprint revolution" in biology and science more generally. Polka began working full-time at ASAPbio in 2016 after funding was granted from the Simons Foundation, Sloan Foundation, Arnold Foundation, and Gordon and Betty Moore Foundation.
In 2016 Polka was described in the journal Nature as an "agent of change" for explaining how junior researchers can increase the impact of their work. For instance, ASAPbio encourages preprints within biology. ASAPbio tries to mitigate the effect of lengthy waiting times before publications are reviewed and published, following the example of physics, computer science and maths, fields that have already adopted preprints. She has also taken an interest in strategies for preventing sexual harassment in the scientific community. In 2017, PLOScast interviewed Polka about her work which contributes to the changing way that science is published.
Since 2019, ASAPBio has begun to host open databases to collate information about academic publishing practices. ReimagineReview tracks the different peer review policies and models of academic journals, with a focus on experimental forms of peer review. The Transpose database extends on this to cover journal policies including on peer review, co-reviewing, preprints, licensing, and versioning.
Awards and honors
Beckman Coulter Distinguished Graduate Student Prize (American Society for Cell Biology) (2013)
Jane Coffin Childs Fellowship (2013–2016)
References
External links
Rescuing Biomedical Research
ASAPbio
Systems biologists
Harvard Medical School faculty
Living people
American molecular biologists
American women molecular biologists
University of California alumni
Synthetic biologists
Open content activists
University of North Carolina at Chapel Hill alumni
21st-century American chemists
21st-century biochemists
21st-century American women scientists
American women biochemists
Year of birth missing (living people)
American women academics | Jessica Polka | [
"Biology"
] | 975 | [
"Synthetic biology",
"Synthetic biologists"
] |
58,144,438 | https://en.wikipedia.org/wiki/Birch%20Tree%20in%20a%20Storm | Birch Tree in a Storm (Norwegian - Bjerk i storm) is an 1849 oil painting by the Norwegian artist Johan Christian Dahl, measuring 92 by 72 cm. It is owned by the Bergen Billedgalleri, now part of the KODE in Bergen. It shows a tree seen by the artist during a descent into Måbøgaldene on the way to Eidfjord.
Sources
1849 paintings
Paintings by Johan Christian Dahl
Paintings in Bergen
Oil paintings
Paintings of trees
Works about weather | Birch Tree in a Storm | [
"Physics"
] | 99 | [
"Weather",
"Physical phenomena",
"Works about weather"
] |
72,099,131 | https://en.wikipedia.org/wiki/Light-induced%20fluorescence%20transient | A light-induced fluorescence transient (LIFT) is a device to remotely measure chlorophyll fluorescence in plants in a fast and non-destructive way. By using a series of excitation light pulses, LIFT combines chlorophyll fluorescence data with spectral and RGB information to provide insights into various photosynthetic traits and vegetation indices. LIFT combines the pump-probe method with the principle of laser-induced fluorescence.
Fluorescence measurement principle
A LIFT measures photosynthesis by exposing the plant to short flashes of blue light and analyzing the changes in fluorescence over time by the help of the FRR technique.
LIFT FRR technique
The LIFT fast repetition rate (FRR) fluorescence technique is a method for measuring plant fluorescence. It uses a series of short bursts of blue light pulses from a LED to excite photosystem II in the plant. When the quinone acceptor A (QA) reaches its capacity for binding electrons, the system becomes saturated and consequently red fluorescence is emitted. This is regulated by a precise excitation protocol, which consists of a saturation sequence (SQA) and a relaxation sequence (RQA) with a set of short excitation flashes (1 μs).
The fluorescence can then be measured with FRR fluorometry. For that purpose, the LIFT instrument has a built-in optical interference filter to separate the red chlorophyll fluorescence from reflected light, with a wavelength of 685 ± 10 nm.
The fluorescence transient resulting from this excitation protocol shows the kinetics of the reduction of QA and its subsequent re-oxidation, and can be used to calculate various photosynthetic indicators. These indicators provide information on the level of photosynthetic activity, such as the efficiency of light utilization, the quantum yield of photochemical conversion, and the rate of electron transport.
LIFT-retrieved photosynthetic indicators
The LIFT system measures chlorophyll fluorescence by stimulating the plant with excitation light, leading to an increase in fluorescence to its maximum (Fm'). The naturally occurring fluorescence (F') can also be measured without the excitation light. The variable fluorescence (Fq') can be calculated as the difference between Fm' and F'. The Photosystem II operating efficiency can be calculated using the equation:
Fq'/Fm' = (Fm' - F')/ Fm'
For the relaxation sequence (RQA), different relaxation parameters can be calculated according to different time sections:
Fr1, ~ 0.625 ms after the maximum Fluorescence has occurred and
Fr2, ~ 6.5 ms after the maximum Fluorescence has occurred.
These parameters can be used for calculating the reoxidation efficiency of QA i.e. the kinetics of electron transfer between QA to PQ pool to photosystem I for light-adapted plants.
Development history and models
The concept for an airborne LIFT instrument was developed by Zbigniew Kolber at Rutgers University in 1998. The first field test was conducted at Biosphere 2 in Arizona in 2002 using a stationary large LIFT setup equipped with a laser operating at a distance of up to 50 meters. The prototype instrument was later refined and improved at the Carnegie Institute, Stanford, and the Agricultural Research Center in Arizona, where the first attempt to operate it on a tractor frame was made. In 2010 several instruments were transferred from Carnegie to the Forschungszentrum Jülich where they are used for laboratory and field research in robotic positioning systems for non-invasive, high-throughput data acquisition.
Current research
In recent research, LIFT has been used in laboratory settings to explore the kinetics of photosynthesis and was also implemented in high-throughput phenotyping platforms for early drought detection. In a more recent publication, the device has been used to study the effects of future elevated atmospheric CO2 concentrations on the seasonal photosynthesis dynamics of different wheat cultivars. The authors showed that the elevated CO2 concentration increased the photosynthetic efficiency, mainly during vegetative growth.
References
Photosynthesis
Fluorescence techniques
Measurement | Light-induced fluorescence transient | [
"Physics",
"Chemistry",
"Mathematics",
"Biology"
] | 854 | [
"Physical quantities",
"Quantity",
"Photosynthesis",
"Measurement",
"Size",
"Biochemistry",
"Fluorescence techniques"
] |
72,099,629 | https://en.wikipedia.org/wiki/Leucocoprinus%20nanianae | Leucocoprinus nanianae is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1946 by the French mycologist Gilbert Bouriquet who classified it as Leucocoprinus nanianae. This species is currently accepted but appears to have received no attention since and may have simply been forgotten about as the publication in which it was described, Bulletin l’Académie Malgache, Nouvelle série, tome 25 is rare and contains many other species for which there is no information available.
Description
Leucocoprinus nanianae is a large white dapperling mushroom with white flesh. The description for this species very closely matches that of Leucocoprinus cretaceus and it is possible that it is simply a synonym.
Cap: Starts globular before spreading out and expanding to 15cm wide, without an umbo. The surface is white and powdery or floury with some small bunches of fibrils that are coloured very light brown. The illustration for this species shows some yellowing at the centre disc and possibly at the gills where they meet the stem although this is not described in the text. Stem: 15cm long and 15mm thick with a bulbous base. The surface is white and covered in a powdery coating the same as the cap, it is flexible when mature and hollows with age but when immature the stem is in the shape of an elongated bulb. No details of the stem ring are noted besides that it is well developed however the accompanying illustration shows a large ring above the middle of the stem or towards the top (apical to superior). Gills: Free, crowded and cream coloured. Spore print: Very light creamy white. Spores: 8.5-12.25 x 5.5-8.5 μm. Dextrinoid. Guttulate with a thick membrane and large germ pore, very very pale yellow. Smell: Pleasant. Taste: Pleasant.
Habitat and distribution
The specimens studied by Bouriquet were found growing in a large cluster on an old pile of garbage near the agricultural station of Nanisana in Madagascar during December of 1942. What this 'garbage' consisted of is not specified and it is possible that Bouriquet may have been describing a compost heap at the agricultural station. L. cretaceus and other Leucocoprinus species are very versatile saprotrophs which are capable of growing on many different substrates so compost, manure, plant debris or wood are all possible.
GBIF has no recorded observations for this species.
Etymology
L. nanianae was presumably named for the location in which it was found, Nanisana, Madagascar. The accompanying illustration for this species created by Mare Rabarijaona is captioned 'Leucocoprinus Nanisanae' so it is unclear which name was intended and which was in error.
Edibility
Bouriquet fed 400g of cooked mushroom to an 'average weight dog' and noted that it did not cause any trouble. This of course cannot be assumed as ensuring the mushroom is safe for human consumption however it was also noted that some of the natives considered the mushroom edible.
Similar species
Leucocoprinus cretaceus and Leucocoprinus elaeidis are described similarly and mostly only differ in the noted presence of a yellow or light brown colour accenting the otherwise white, powdery surface. L. elaeidis is also only documented in one old book and it is possible that it and L. nanianae are simply synonyms of L. cretaceus that have yet to be reclassified. L. cretaceus is the only routinely documented Leucocoprinus species that resembles this description and some observations of it display some yellow or brown discolouration at the cap or a yellow stem beneath the white scales. At present it is not clear if these are all the same species or if some distinction should be made based on these characteristics.
References
nanianae
Fungi described in 1946
Fungus species | Leucocoprinus nanianae | [
"Biology"
] | 827 | [
"Fungi",
"Fungus species"
] |
72,100,340 | https://en.wikipedia.org/wiki/Leucocoprinus%20tanetensis | Leucocoprinus tanetensis is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1946 by the French mycologist Gilbert Bouriquet who classified it as Leucocoprinus tanetensis. This species is currently accepted but appears to have received no attention since and may have simply been forgotten about as the publication in which it was described, Bulletin l’Académie Malgache, Nouvelle série, tome 25 is rare and contains many other species for which there is no information available.
Description
Leucocoprinus tanetensis is a large white mushroom with white flesh which does not discolour red. The description for this species more closely resembles a Chlorophyllum species so it may be a synonym for another species which has yet to be reclassified.
Cap: Starts ovoid before spreading out and expanding to 14cm wide, has a slight, broad umbo. The surface is creamy white and covered in many brown scales. Stem: Over 20cm long and 10mm thick with a bulbous base. It is firm with a white surface and a hollow, fibrous centre. No details of the stem ring are noted besides that it is very developed however the accompanying illustration shows a large ring towards the top of the stem (apical). Gills: Free, crowded and whitish but discolouring greenish with age. Spore print: Cream. Spores: 12.5-15.5 x 8.75-12 μm. Dextrinoid. Guttulate with a thick membrane and a very distinct germ pore, very pale yellow. Smell: Pleasant. Taste: Pleasant.
Habitat and distribution
The specimens studied by Bouriquet were found growing in open grassy areas in Magagascar near cattle manure and were often found on the low heights known as tanety. These mushrooms were found in January near Antananarivo and were said to be abundant during this month and common all over the island.
GBIF has no recorded observations for this species.
Etymology
Tanety is the local term used to describe hillside areas. L. tanetensis was likely named for this word.
Edibility
Bouriquet states that this species is one of the best edible mushrooms in Grande-Île, which is another name for Madagascar. He notes that it was listed as one of the species authorised for sale in Antananarivo.
References
tanetensis
Fungi described in 1946
Fungus species | Leucocoprinus tanetensis | [
"Biology"
] | 499 | [
"Fungi",
"Fungus species"
] |
72,100,476 | https://en.wikipedia.org/wiki/Sparse%20identification%20of%20non-linear%20dynamics | Sparse identification of nonlinear dynamics (SINDy) is a data-driven algorithm for obtaining dynamical systems from data. Given a series of snapshots of a dynamical system and its corresponding time derivatives, SINDy performs a sparsity-promoting regression (such as LASSO) on a library of nonlinear candidate functions of the snapshots against the derivatives to find the governing equations. This procedure relies on the assumption that most physical systems only have a few dominant terms which dictate the dynamics, given an appropriately selected coordinate system and quality training data. It has been applied to identify the dynamics of fluids, based on proper orthogonal decomposition, as well as other complex dynamical systems, such as biological networks.
Mathematical Overview
First, consider a dynamical system of the form
where is a state vector (snapshot) of the system at time and the function defines the equations of motion and constraints of the system. The time derivative may be either prescribed or numerically approximated from the snapshots.
With and sampled at equidistant points in time (), these can be arranged into matrices of the form
and similarly for .
Next, a library of nonlinear candidate functions of the columns of is constructed, which may be constant, polynomial, or more exotic functions (like trigonometric and rational terms, and so on):
The number of possible model structures from this library is combinatorically high. is then substituted by and a vector of coefficients determining the active terms in :
Because only a few terms are expected to be active at each point in time, an assumption is made that admits a sparse representation in . This then becomes an optimization problem in finding a sparse which optimally embeds . In other words, a parsimonious model is obtained by performing least squares regression on the system with sparsity-promoting () regularization
where is a regularization parameter. Finally, the sparse set of can be used to reconstruct the dynamical system:
References
Algorithms | Sparse identification of non-linear dynamics | [
"Mathematics"
] | 402 | [
"Applied mathematics",
"Algorithms",
"Mathematical logic"
] |
72,100,497 | https://en.wikipedia.org/wiki/List%20of%20commelinid%20families | The commelinids are a group of 29 interrelated families of flowering plants, named for one of the four included orders, Commelinales. This subgroup of the monocots accounts for most of the global agricultural output; the grass family alone contains the major cereal grains (including rice, wheat, and maize or corn), along with forage grasses, sugar cane, and bamboo. The palm, banana, ginger, pineapple and sedge families are also commelinids.
Traits common to most commelinids include partially fluorescent cell walls, starchy seeds and an extra layer of epidermal wax. Like other monocots, they usually have a single embryonic leaf (cotyledon) in their seeds, scattered vascular systems, leaves with parallel veins, flowers with parts in threes or multiples of three, and roots that can develop in more than one place along the stems. These plants are found worldwide, even in mainland Antarctica; two species of grass are the only vascular plants found there.
Glossary
From the glossary of botanical terms:
annual: a plant species that completes its life cycle within a single year or growing season
basal: attached close to the base (of a plant or an evolutionary tree diagram)
climber: a vine that leans on, twines around or clings to other plants for vertical support
herbaceous: not woody; usually green and soft in texture
perennial: not an annual or biennial
woody: hard and lignified; not herbaceous
The APG IV system is the fourth in a series of plant taxonomies from the Angiosperm Phylogeny Group.
Families
See also
List of plant family names with etymologies
Notes
Citations
References
See the licence.
See Kew's Terms of Use for license.
Systematic
Commelinid
Commelinid families
commelinid families
Commelinids | List of commelinid families | [
"Biology"
] | 383 | [
"Lists of biota",
"Lists of plants",
"Plants"
] |
72,101,233 | https://en.wikipedia.org/wiki/Malamba%20%28drink%29 | Malamba is a traditional alcoholic beverage in Cameroon, Equatorial Guinea, and Gabon made by fermenting sugarcane juice. The canes are crushed in a mortar, and the juice is left to ferment for approximately two weeks. The flavor and texture is similar to the Latin American drink guarapo. To accelerate the process of fermentation, bark from the Garcinia kola (bitter kola in English, known as essoc or onaé in Cameroon) can be added to the juice. Corn is also sometimes added during the fermentation process to increase the alcohol content. In Gabon, the drink is also known as musungu or vin de canne (cane wine) in French.
See also
Palm wine
References
Fermented drinks
Gabonese cuisine
Cameroonian cuisine | Malamba (drink) | [
"Biology"
] | 161 | [
"Fermented drinks",
"Biotechnology products"
] |
72,101,250 | https://en.wikipedia.org/wiki/Guarapo%20%28drink%29 | Guarapo (from the Quechua warapu) is a Latin American fermented alcoholic drink derived from sugarcane juice.
"Guarapo" is also a Spanish word for sugarcane juice itself, but in much of Latin America it is used to refer specifically to the fermented product. The Quechua word warapu signifies the juice of crushed cane.
Variations
Mexico
In the Mexican state of Tabasco, during the Spanish colonial period in the 16th century, when sugarcane was introduced from the Caribbean, the Chontal Maya people began to produce the drink by fermenting sugarcane juice. It became very popular among the Indigenous population, who consume it primarily at parties and celebrations, including Day of the Dead. They also produce guarapo de maíz, or corn guarapo, which is made by fermenting toasted corn, panela, and water.
Cuba
In Cuba, the drink is prepared in rural communities by dissolving honey or panela in water and fermenting it with a type of yeast commonly referred to as cunchos or supias. This yeast is often shared among those who produce the beverage. It is also common to produce the beverage by crushing sugarcane in a trapiche or mill, either drinking it fresh or fermenting it. This is also how the typical Cuban drink aguardiente is produced.
Central and South America
Guarapo is particularly well known the Latin American nations of Panama, Puerto Rico, the Dominican Republic, Ecuador, Venezuela, Colombia, Bolivia, and Peru. Venezuelans also refer to coffee mixed with a large amount of water as guarapo. Colombians generally drink guarapo, fermented with yeast known as cunchos in clay vessels. The Festival of Guarapo is held in the Colombian town of Tuluá.
References
Fermented drinks
Mexican cuisine
Cuban cuisine
Colombian cuisine
Paraguayan cuisine
Venezuelan cuisine
Sugar-based alcoholic drinks | Guarapo (drink) | [
"Biology"
] | 390 | [
"Fermented drinks",
"Biotechnology products"
] |
72,101,545 | https://en.wikipedia.org/wiki/Energy%20Reports | Energy Reports is a peer-reviewed open-access scientific journal covering all aspects of energy research. The journal was established in 2015 and is published by Elsevier. The editor-in-chief is Nelson Fumo (University of Texas at Tyler). Authors pay article processing charges, but do not retain unrestricted copyrights and publishing rights.
Abstracting and indexing
The journal is abstracted and indexed in Ei Compendex, Scopus, and the Science Citation Index Expanded. According to the Journal Citation Reports, the journal has a 2021 impact factor of 4.937.
References
External links
Energy and fuel journals
Academic journals established in 2015
English-language journals
Elsevier academic journals
Creative Commons Attribution-licensed journals
Continuous journals | Energy Reports | [
"Environmental_science"
] | 150 | [
"Environmental science journals",
"Energy and fuel journals"
] |
72,101,808 | https://en.wikipedia.org/wiki/Time%20in%20the%20Dominican%20Republic | The Dominican Republic observes Atlantic Standard Time (UTC−4) year-round. Daylight saving time was used in the past.
History
At midday April 1, 1933, Rafael Trujillo ordered a decree that established a national time zone for the Dominican Republic, which was set to five hours behind Greenwich Mean Time (GMT). Prior to that, time in the Dominican Republic was governed by Santo Domingo Mean Time, which was 4 hours and 40 minutes behind GMT.
On October 27, 1974, the Dominican Republic moved from Eastern Standard Time to Atlantic Standard Time.
IANA time zone database
In the IANA time zone database, Dominican Republic is given one zone in the file zone.tab—America/El_Salvador. "SV" refers to the country's ISO 3166-1 alpha-2 country code. Data for Dominican Republic directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:
References
External links
Current time in Dominican Republic at Time.is
Time in Dominican Republic at TimeAndDate
Time by country
Geography of the Dominican Republic | Time in the Dominican Republic | [
"Physics"
] | 225 | [
"Spacetime",
"Physical quantities",
"Time",
"Time by country"
] |
72,102,901 | https://en.wikipedia.org/wiki/Archtober | Archtober is a citywide celebration of architecture in New York City organized by the Center for Architecture. The festival's name is a portmanteau of architecture and October, the month in which it is celebrated.
The festival is known for its Building of the Day highlight, which provides a focus on a specific building or architect thereof, but also includes exhibits and other public programs that celebrate architecture and design.
See also
Open House New York
References
Festivals established in 2010
Festivals in New York City
Architecture festivals | Archtober | [
"Engineering"
] | 103 | [
"Architecture stubs",
"Architecture festivals",
"Architecture"
] |
72,102,913 | https://en.wikipedia.org/wiki/Ludmila%20Prokunina-Olsson | Ludmila Prokunina-Olsson is a molecular medical geneticist who conducts genetic and functional analyses downstream of genome-wide association studies (GWAS) for various human traits, including cancer, immune and infectious diseases. She is chief of the Laboratory of Translational Genomics (LTG) at the National Cancer Institute.
Life
Prokunina-Olsson received an M.Sc. in molecular genetics from Moscow State University. She earned a Ph.D. in medical genetics from Uppsala University Faculty of Medicine in 2004. Her dissertation was titled Strategies for identification of susceptibility genes in complex autoimmune diseases. Marta Alarcon-Riquelme was her doctoral advisor and Juha Kere was an opponent of her dissertation.
During 2005 to 2008, she was a visiting fellow with Francis Collins in the genome technology branch of the National Human Genome Research Institute. Prokunina-Olsson joined the Laboratory of Translational Genomics (LTG) of the division of Cancer Epidemiology and Genetics (DCEG) as a research fellow in June 2008. She became a tenure-track investigator in April 2010 and was awarded National Institutes of Health (NIH) scientific tenure and promoted to senior investigator in December 2014. She became acting chief of LTG in February 2018 and was appointed as chief in December 2018. Prokunina-Olsson explores the connections between the genome-wide association studies (GWAS)-identified genetic susceptibility variants and molecular phenotypes of importance for cancer. Some of her findings have resulted in translational and clinical applications.
References
Living people
1967 births
Place of birth missing (living people)
Moscow State University alumni
Uppsala University alumni
National Institutes of Health people
Medical geneticists
21st-century Russian women scientists
Russian geneticists
Women geneticists
Russian emigrants to the United States
Expatriate academics in the United States
Molecular geneticists
Russian medical researchers
Women medical researchers
Cancer researchers
21st-century Russian biologists | Ludmila Prokunina-Olsson | [
"Biology"
] | 400 | [
"Molecular geneticists",
"Molecular genetics"
] |
72,105,261 | https://en.wikipedia.org/wiki/Bow-tie%20diagram | A bow-tie diagram is a graphic tool used to describe a possible damage process in terms of the mechanisms that may initiate an event in which energy is released, creating possible outcomes, which themselves produce adverse consequences such as injury and damage. The diagram is centred on the (generally unintended) event with credible initiating mechanisms on the left (being where reading diagrams starts) and resulting outcomes and associated consequences (such as injury, loss of property, damage to the environment, etc.) on the right. Needed control measures, or barriers, can be identified for each possible path from mechanisms to the final consequences. The shape of the diagram resembles a bow tie, after which it is named.
A bow-tie diagram can be considered as a simplified, linear, and qualitative representation of a fault tree (analyzing the cause of an event) combined with an event tree (analyzing the consequences), although it can maintain the quantitative, probabilistic aspects of the fault and event tree when it is used in the context of quantified risk assessments.
Bow-tie analysis is used to display and communicate information about risks in situations where an event has a range of possible causes and consequences. A bow tie is used when assessing controls to check that each pathway from cause to event and event to consequence has effective controls, and that factors that could cause controls to fail (including management systems failures) are recognized. It can be used proactively to consider potential events and also retrospectively to model events that have already occurred, such as in an accident analysis. The diagram follows the same basic principles as those on which fault tree analysis and event tree analysis are based, but, in being far less complex than these, is attractive as a means of rapidly establishing an overall scope of risk concerns for an organisation, only some few of which may justify those more rigorous and logical methods.
Bow-tie diagrams are used in several industries, such as oil and gas production, the process industries, aviation, and finance.
History
It has been commonly noted that the earliest mention of the bow-tie methodology appeared in the Imperial Chemical Industries (ICI) course notes of a lecture on hazard analysis given at the University of Queensland, Australia in 1979. Other sources point to Derek Viner (in the same year) at the then Ballarat College of Advanced Education (now the Federation University of Australia), who drew it as an aid to visualization of his generalized time sequence model (GTSM) for damage processes. The more complex risk analysis tools of fault tree analysis, event tree analysis use the same principle: Things go wrong, there is a reason for that and a result too, with the result generating the adverse consequences. The bow-tie diagram introduces the concept of a central energy-based event (the "bow tie knot") in which the damaging properties of the energy are no longer under control so that they result in outcomes and consequences.
Royal Dutch Shell is considered to be the first major company to successfully integrate bow-tie diagrams into their business practices, at least since the early 1990s.
Logic and structure of the diagrams
Bow-tie diagrams contribute to the identification, description and understanding of the different types of hazards that can arise in a given situation, facility or production process. They also help identify the relevant risk control measures (barriers) for a given hazard.
The fact that scientific effort benefits greatly from a focus on the process giving rise to the phenomenon of interest is well known in several scientific domains, as noted by William Haddon. The generalized time sequence model (GTSM) was developed in the 1970s by Viner as a process model suited to understanding this process to the phenomenon of unwanted damage. Bow-tie diagrams are a simplified extract of this, conceived of (and then named by students) during a lecture to assist explanation.
Bow-tie diagrams are centred on a central event in which the energy necessary to bring about the ultimate undesired consequences is released. In William Rowe’s seminal work, which explained half of the process of damage, the event of interest is defined as what produces outcomes and consequences of interest and outcomes as what results from an event. Derek Viner resolved this circularity by defining the event as "the point in time when control is lost of the potentially damaging properties of the energy source of interest." This is sometimes referred to as the top event (a fault-tree term) or the critical event. Thus, a bow-tie analysis is centred on an energy-based event. The need for energy sources in any damage process had been noted by Lewis DeBlois as early as 1926 as well as Gibson and Haddon in the decade prior to the introduction of the bow-tie diagram. It is evident that any central event may be originated by more than one mechanism and that, following the release of energy, a number of different outcomes may result. As Rowe made clear, it is these various unwanted outcomes that produce the adverse consequences of injury, damage etc.
Credible initiating mechanisms (which some call causes, triggers, threats, etc.) are shown on the left of the central event and its ultimate outcomes and consequences, such as injury, loss of property, damage to the environment, etc. on the right. This left to right flow of the process is also a time axis. Control barriers, either hard/engineered or administrative/procedural, are identified for each path from the mechanisms to the final outcomes.
For example, pressure in a process vessel is a form of energy that can be released if containment is breached (the central event). Possible mechanisms for breach of containment, shown to the left, include structural degradation (abrasion, corrosion, fatigue), spurious pressurization above design limits, inadvertent opening, etc. Shown to the right of the central event, are the results/outcomes of the release (e.g., noise, blast overpressure propagation, flying debris, loss of fluid, etc.) When mechanisms and outcomes and subsequently routes to adverse consequences are understood, the analyst can ensure that control measures (often now called barriers) exist to stop the initiating mechanisms from resulting in the central event and the central event from leading to the ultimate unwanted outcomes and consequences. Left-hand side (mechanism) control measures are, in this example, external and internal surface coatings, vessel inspection (internal and external), wall thickness measurements, pressure safety valves, etc. While some are relevant to design and commissioning, others are to maintenance and condition monitoring. Outcome (right-hand side) control measures in this example would include nearby structures designed to withstand modelled blast overpressure.
Bow-tie diagrams are typically a qualitative tool, used for simple damage process analysis as well as for illustrative purposes, such as in training courses to plant operators and in support of safety cases. However, a different type of bow-tie diagram exists that is more apt at supporting quantified risk analysis. This diagram is essentially the combination of a fault tree and an event tree and maintains the Boolean and probabilistic features of those approaches.
Use in various domains
Bow-tie diagrams are used in various disciplines and domains, including for example:
Occupational safety and health (OSH)
Process safety
Aviation safety
Information security and cyber security risks
Finance
Several software packages are available in the market for bow-tie diagram creation and management.
References
Accident analysis
Diagrams
Process safety
Safety engineering | Bow-tie diagram | [
"Chemistry",
"Engineering"
] | 1,494 | [
"Chemical process engineering",
"Systems engineering",
"Safety engineering",
"Process safety"
] |
72,106,078 | https://en.wikipedia.org/wiki/Schramm%27s%20model%20of%20communication | Schramm's model of communication is an early and influential model of communication. It was first published by Wilbur Schramm in 1954 and includes innovations over previous models, such as the inclusion of a feedback loop and the discussion of the role of fields of experience. For Schramm, communication is about sharing information or having a common attitude towards signs. His model is based on three basic components: a source, a destination, and a message. The process starts with an idea in the mind of the source. This idea is then encoded into a message using signs and sent to the destination. The destination needs to decode and interpret the signs to reconstruct the original idea. In response, they formulate their own message, encode it, and send it back as a form of feedback. Feedback is a key part of many forms of communication. It can be used to mitigate processes that may undermine successful communication, such as external noise or errors in the phases of encoding and decoding.
The success of communication also depends on the fields of experience of the participants. A field of experience includes past life experiences as well as attitudes and beliefs. It affects how the processes of encoding, decoding, and interpretation take place. For successful communication, the message has to be located in the overlap of the fields of experience of both participants. If the message is outside the receiver's field of experience, they are unable to connect it to the original idea. This is often the case when there are big cultural differences.
Schramm holds that the sender usually has some goal they wish to achieve through communication. He discusses the conditions that are needed to have this effect on the audience, such as gaining their attention and motivating them to act towards this goal. He also applies his model to mass communication. One difference from other forms of communication is that successful mass communication is more difficult since there is very little feedback. In the 1970s, Schramm proposed many revisions to his earlier model. They focus on additional factors that make communication more complex. An example is the relation between sender and receiver: it influences the goal of communication and the roles played by the participants.
Schramm's criticism of linear models of communication, which lack a feedback loop, has been very influential. One shortcoming of Schramm's model is that it assumes that the communicators take turns in exchanging information instead of sending messages simultaneously. Another objection is that Schramm conceives information and its meaning as preexisting entities rather than seeing communication as a process that creates meaning.
Background
Schramm's model of communication was published by Wilbur Schramm in 1954. It is one of the earliest interaction models of communication. It was conceived as a response to and an improvement over earlier attempts in the form of linear transmission models, like the Shannon–Weaver model and Lasswell's model. Models of communication are simplified presentations of the process of communication and try to explain it by discussing its main components and their relations.
For Schramm, a central aspect of communication is that the participants "are trying to establish a 'commonness by sharing an idea or information. In this regard, communication can be defined as "the sharing of an orientation toward a set of informational signs" and is based on a relation between the communicators. So when a person calls the fire department to report a fire in their home, this is an attempt to share information about the fire. This sharing happens through messages. For Schramm, messages are made up of signs. Each sign corresponds to some element in experience, like the sign "dog" which "stands for our generalized experience of dogs". This sign is meaningless for someone who has never experienced dogs before or who does not associate the sign with their experiences of dogs.
The theories of psychologist Charles Osgood were a significant influence and inspired Schramm to formulate his model. According to Osgood, meaning is located not just in the message but also in the social context. His psycholinguistic approach focuses on how external stimuli elicit internal responses in the form of interpretations. These responses mediate between the stimulus and its meaning. Osgood's ideas influenced Schramm in two important ways: (1) he posited a field of shared experience acting as the background of communication and (2) he added the stages of encoding and decoding as internal responses to the process. Because of these influences, some theorists refer to Schramm's model as the "Osgood–Schramm model".
Most theorists identify Schramm's model with his 1954 book The process and effects of mass communication and present it as a reaction to earlier models developed in the late 1940s. However, marketing scholar Jim Blythe argues that Schramm's model is of earlier origin and was already present in Schramm's 1949 book Mass Communication.
Overview and basic components
For Schramm, communication has in its most basic form three parts: a source, a message, and a destination. The source can be an individual or an organization, like a newspaper or a television station. The same is true for the destination. The process starts in the sender's mind, where the message originates in the form of an idea. To share this information, the source needs to encode it first into symbolic form since the idea cannot be transmitted directly from mind to mind. This can happen in various ways: the signs can be linguistic (like written or spoken words) or non-linguistic (like pictures, music, or animal sounds). They are then transmitted through a channel, for example, as sounds for a face-to-face conversation, as ink on paper for a letter, or as electronic signals in the case of text messaging. At this stage, noise may interfere with the transmission and distort the message. Once the message reaches the receiver, the reverse process of decoding is applied: the receiver attaches meaning to the signs according to their own field of experience. This way, they try to reconstruct the sender's original idea. The process continues when the receiver returns a new message as feedback to the original sender.
The process of communication can fail in various ways. For example, the message may be distorted by external noise. But errors can also occur at the stages of encoding and decoding when the source does not use the correct signs or when the pattern of decoding does not match the pattern of encoding. A further problem is posed if the original information is faulty, to begin with. For effective communication, all these negative influences need to be avoided.
Schramm's model is based on the Shannon–Weaver model. According to the Shannon–Weaver model, communication is an interaction of various components. A source translates a message into a signal using a transmitter. The signal is then sent through a channel to a receiver. The receiver translate the signal back into a message and makes it available to a destination. The steps of encoding and decoding in Schramm's model perform the same role as transmitter and receiver in the Shannon–Weaver model. Because of its emphasis on communication as a circular process, the main focus of Schramm's model is on the behavior of senders and receivers. For this reason, it does not involve a detailed technical discussion of the channel and influences of noise, unlike the Shannon–Weaver model.
Feedback
The role of feedback is one innovation of Schramm's model in comparison to earlier models. Schramm sees communication as a dynamic interaction in which two participants exchange messages. That means that the process of communication does not end in the receiver's mind. Instead, upon receiving a message, the communicator returns some feedback: they formulate a new message in the form of an idea, encode it, and convey it to the original sender, where the process starts anew. Communication is an endless process in the sense that people constantly decode and interpret their environment to assign meaning to it and encode possible responses to it.
Models without a feedback loop, like the Shannon–Weaver model and Lasswell's model, are called linear transmission models. They contrast with interaction models, also known as non-linear or circular transmission models. Schramm rejects the idea of a passive audience present in linear models of communication. He argues instead that the audience should be understood as a full partner. Feedback is a vital aspect of many forms of communication. It can be used to confirm that the message was received and to mitigate the influence of noise. For example, the message may get distorted on the way or the receiver may misinterpret it. In such cases, the feedback loop makes it possible to assess whether such errors occurred and, if so, repeat the message to ensure that it is understood correctly.
Schramm also discusses another form of feedback that does not depend on the other person. This happens when the sender pays attention to their own message, for example, when reading through a letter one just wrote to check its style and tone.
Field of experience
Another innovation of Schramm's model is the role of fields of experience. A field of experience is a mental frame of reference. It includes past life experiences as well as the attitudes, values, and beliefs of the communicators. Each participant has their own field of experience. It determines how the processes of encoding, decoding, and interpretation take place. For example, an American is unable to encode their message in Russian if they have never learned this language. And if a person from an indigenous tribe has never heard of an airplane then they are unable to accurately decode messages about airplanes. The more the participants are alike, the more their fields of experience overlap. For communication to be successful, the message has to be located within both fields of experience, i.e. in their overlap.
The bigger the cultural differences, the more difficult effective communication becomes. This is especially relevant for communication across national boundaries. Blythe cites this lack of overlap as an example of failed communication in the case of foreign advertisements, which may appear incomprehensible or unintentionally humorous. The lack of overlap can also happen for people within the same culture, for example, when an amateur tries to read specialist scientific literature. In some cases, such problems can be avoided if the sender is able to encode their message using an easy expression that is accessible to the destination. The concept of a field of experience is similar to what later models refer to as social and cultural contexts.
Conditions of successful communication
Communication is usually tied to some intended effect. So putting an advertisement in a newspaper, scolding a child, or engaging in a job interview are forms of communication directed at different goals. Communication is not always successful and the message may fail to achieve the intended effect. Schramm lists four conditions of successful communication. The message must be designed (1) to gain the attention of the destination and (2) to be understandable to get the meaning across. Additionally, it must (3) arouse needs in the destination, and (4) suggest a way how these needs can be met.
To get the attention of the audience, the message must be accessible to them. When talking, for example, one must talk loud enough to be heard. To ensure that the message is understandable, the sender must be aware of the field of experience of the audience in order to choose words and examples that are familiar to them. Through the relation to the destination's needs, the message can unfold its effect by motivating them to respond.
Depending on the message and the intended effect, it can address needs like security, status, or love. This aspect plays a central role in all forms of advertisement. A good knowledge of one's audience's character is required to understand which need to arouse and how to arouse it. This depends also on the specific situation and the circumstances, for example, whether the audience is in the right mood and whether the intended response is socially acceptable in the given situation. To unfold its effect, there has to be some form of action that the audience can perform to satisfy this need. There are usually many actions available. The sender may use the message to suggest the action that is most in tune with the effect they intend to provoke. For example, a political party may use a campaign event to spread fear of an external threat in order to arouse the audience's need for security. The party may then promise to eliminate this threat to get the audience to act in tune with its intended goal: to secure their votes.
Application to mass communication
For mass communication, the source is usually not an individual but rather an organization like a newspaper or a broadcasting network. The basic steps like encoding and decoding are the same but they are not performed by a single person but by a group of people, like the employed reporters and editors. The destinations of mass communication are individual people, like the readers of a newspaper. The hallmark of mass communication is that the message reaches a very large number of people. This stands in contrast to face-to-face communication taking place between two or a small number of people. Another difference is that there is very little direct feedback in mass communication. For example, it happens very seldom that a viewer contacts a broadcast network or that a reader writes a letter to an editor. Feedback is here often more indirect: people may stop to buy a service or to view a program if they are not satisfied with it, usually without providing a reason to the sender for their decision. This lack of feedback makes effective communication more difficult since it is not directly obvious to the sender whether their message had the intended effect. This is one of the reasons why mass communication providers often conduct audience research. This way, they can obtain vital information about their target audience so they can formulate their messages accordingly.
It is very difficult to predict the effects of mass communication since the effect differs a lot from person to person based on their personality, mood, and current situation. An additional factor in this regard is that the effects are not restricted to direct effects on the person receiving the message. Instead, they are also indirect: the receiver is part of a social environment and may share, criticize, and reflect on the message with the people in their environment.
Later developments
Schramm proposed revisions to his model in the 1970s. He explained that many developments in the field of communication studies since his first model had shown that communication is a very complex phenomenon. He agreed that his initial model was too simple to do justice to this complexity. He tried to address these shortcomings by developing a relational model of communication. These changes were influenced by David Berlo's model of communication and its focus on the effects of communication. Berlo had argued that the goal of all communication is to influence the behavior of the audience. Schramm's relational model focuses on the relation between sender and receiver. The relation includes the totality of the past experiences the communicators have had with each other. It can be based on past face-to-face contact with the other party, as when meeting a friend for dinner, but need not be, as would be the case when reading a newspaper article by a reporter one has never met. But even in this case, past experiences shape what the reader expects from the newspaper and what the reporter expects from the readership.
For Schramm, the relation is a basic requirement of communication since communication is about sharing information or attitudes and, in this sense, being in tune with each other. It determines many aspects of communication, like its goal, the roles played by the participants, and the expectations they bring to the exchange. The goal is what the communicators intend to achieve by communicating. In the instructional context, the goal is to transmit information while performance arts are about entertaining the audience. The relation also affects the role of the participants. For instruction, this involves the roles of teacher and student. These roles determine how the participants are expected to contribute to the communicative goal. For example, teachers may share and explain information while students may listen and ask clarifying questions. As the background of communication, the relation also affects how the messages are interpreted. For example, seeing a person as an actor on a stage leads to one interpretation of their messages. But interacting with them during business negotiations results in a very different interpretation of the same messages.
Influence and criticism
Schramm's model has been influential both for its criticism of linear transmission models and for its innovations in trying to overcome them. Schramm was one of the first scholars to challenge the Shannon–Weaver model of communication. According to him, the shortcomming of the Shannon–Weaver model and other linear transmission models is that they assume that the communicative process ends when the message reaches its destination. He terms them "bullet theories of communication" since communication is seen as a magic bullet that goes from active senders to passive receivers in the form of sending ideas to the receivers' mind. Schramm rejects the idea that the audience is a passive receiver and assigns them a more active role: the audience respondes by generates a new message and sends it back to the original as a form of feedback. Many scholars have followed Schramm's criticisms of linear transmission models. They agree that communication is a dynamic exchange involving an active audience and feedback loops. Schramm's other innovations have also been influential, like his concept of the field of experience and his development of relational models in his later work.
A common criticism of Schramm's model focuses on the fact that it describes communication as a turn-based exchange of information. This means that there is no simultaneous messaging: first one participant sends a message, then the other conveys their own message as a form of feedback, later the first participant responds again, etc. However, these processes often happen simultaneously for many forms of communication. For example, in face-to-face conversations like a first date, the listener usually uses facial expressions and body posture to signal their agreement or interest. This happens while the speaker is talking, the listener does not wait for the speaker to finish before engaging in this form of non-verbal communication. This shortcoming of Schramm's model is addressed by so-called transaction models, which allow for simultaneous messaging. The weight of this objection depends on the type of communication analyzed. For some forms, like pen pals exchanging letters or instant messaging, disregarding simultaneous messages has little impact, but in other cases, it is an important factor.
Another criticism of Schramm's model argues that, for Schramm, the information and its meaning exist prior to the communicative act. Communication itself is then just understood as an exchange of messages or meaning. This view is characteristic of transmission models but is rejected by constitutive models. Constitutive models hold that meaning does not exist before the communication but is created in the process. In this regard, the dialog acts as a cooperative process through which meaning is constructed. Such an approach is proposed by Everett Rogers and Thomas Steinfatt. They elaborate Schramm's interactive approach and combine it with the assumption that the communicators create and share meaning with the goal of reaching a mutual understanding. Similar approaches to communication focusing on the co-construction of meaning are presented by S. A. Deetz and G. Mantovani.
A further limitation is that Schramm's model is restricted to communication between two parties. However, there are forms of group communication where more parties are involved.
References
Notes
Citations
Sources
Communication studies
Communication theory
Conceptual modelling
Human communication | Schramm's model of communication | [
"Biology"
] | 4,023 | [
"Human communication",
"Behavior",
"Human behavior"
] |
72,106,450 | https://en.wikipedia.org/wiki/Leucocoprinus%20nigricans | Leucocoprinus nigricans is a species of mushroom producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1973 by the Czech mycologist Bohumil Ježek who classified it as Leucocoprinus nigricans. This species is currently accepted but appears to have received no attention since and may have simply been forgotten about as the issue of Mykologický sborník - Časopis Českých Houbař it was published in is not easily accessible.
Description
Leucocoprinus nigricans is a small white dapperling mushroom with thin (5mm thick) white flesh. Ježek provided only a brief description of this species in Latin and some of the terms used are antiquated now and do not easily translate.
Cap: 2.3cm wide, 1.5cm high and conical when immature expanding to 5.5cm and flattening with age with striations at the edges. The surface is a 'dirty white' colour and has a frosty or fibrous coating when young sometimes with some slight reddening at the top and a sticky surface. Stem: 4.5cm long and 5mm thick with a white, silky and fibrillose surface. Slight striations run vertically up the stem and the base of the stem gradually blackens and may even become black. The white stem ring is located towards the top of the stem but sometimes disappears. Gills: Adnexed, crowded and white. Spore print: White. Spores: Ovoid. 6.5-7.5 x 4-4.5 μm. Smell: Indistinct. Taste: Indistinct.
Habitat and distribution
The specimens studied by Ježek were found growing in groups in Cabo Frio, Brazil in 1971 and the description was published in 1973. Ježek died in Cabo Frio on the first of June 1973 so if he was intending to study this species further, it unfortunately did not happen.
GBIF has no recorded observations for this species.
Etymology
The specific epithet nigricans derives from the Latin for 'blackening' and refers to the colouration of the base of the stem.
References
nigricans
Fungi described in 1973
Fungus species | Leucocoprinus nigricans | [
"Biology"
] | 466 | [
"Fungi",
"Fungus species"
] |
72,107,084 | https://en.wikipedia.org/wiki/Leucocoprinus%20truncatus | Leucocoprinus truncatus is a species of mushroom-producing fungus in the family Agaricaceae.
Taxonomy
It was first described in 1950 from South Africa by Arthur Anselm Pearson who classified it as Lepiota truncata.
In 2012 the German mycologists Erhard Ludwig and Peter Mohr reclassified it as Leucocoprinus truncatus after recording the specimen from an indoor plant pot, this was noted as the first record of the African species in Europe. They suggested the common name of Abgestutzter Faltenschirmling which translates as trimmed or clipped pleated parasol.
Description
Leucocoprinus truncatus is a small white dapperling mushroom with white flesh which does not discolour.
Cap: Starts cylindrical with a flat top or like an 'inverted bucket' before becoming conical and then expanding to up to 1.5 cm wide, campanulate and finally flat convex and is 'rather fleshy'. The cap surface is white at first with a brown centre disc that remains truncate and flattened on the top, the disc breaks up into brown scales which are easily rubbed off to reveal the silky white surface beneath. The cap surface is covered in fine granules or a fine woolly coating (tomentose) and discolours brownish with age or with damage. Stem: Up to 2.5 cm long and 1.5mm thick gradually tapering up from a 4mm wide base. The surface is cream coloured, smooth above the ring but covered in short, fine felty hairs below which can be rubbed off. The base of the stem has some slight brown scales and white mycelium showing. The ascending, membranous stem ring is white but discolours brown with a frayed edge with age and it becomes movable with age. Gills: Free, crowded and whitish at first becoming creamy. Spores: Ovoid to amygdaliform. Dextrinoid and metachromatic. 10-12 x 5.5-6.5 μm.
Also noted is the secretion of light brown droplets or guttation on the cap, stem and ring. Most specimens began to discolour brown, wither and go moldy shortly after maturing.
Pearson's description of Lepiota truncata from 1950 broadly agrees with the description of Leucocoprinus truncatus but contains some additional details not noted in the more recent description. These differences are noted here:
Cap: 1–6 cm wide. The cap edges have striations when old and they often have an appendiculate veil. Stem: 5–6 cm long and 3-5mm thick with a white or pinkish surface. Separable from the cap and solid but hollowing with age. The stem ring is 2-3mm wide and movable, sometimes fragments of it adhere to the cap margins (appendiculate). The position of the ring on the stem is not noted in either description, however accompanying drawings by Mary Maytham Kidd show it toward the top of the cap (superior to apical). Gills: Pearson notes that they have a bulge in the middle (ventricose), are 3-5mm wide with fimbriate edges and that the white surface stains lemon yellow in places. The gills are of several lengths.Spore print: White. Taste: Mild. Smell: None.
Habitat and distribution
The specimens studied by Pearson were found growing in trooping groups near various trees and shrubs in the South-West corner of the former Cape Province of South Africa. They were said to be common during April to June and were also noted as sometimes growing on burnt ground. The specimen studied by Ludwig and Mohr was found in an orchid pot from a bathroom in Europe and was noted as probably the first record of this species from Europe.
GBIF has one recorded observation for this species with a specimen preserved in 2006.
Etymology
The specific epithet truncatus (originally truncata) likely refers to the truncated central disc which this species displays.
References
truncatus
Fungi described in 1950
Fungus species | Leucocoprinus truncatus | [
"Biology"
] | 848 | [
"Fungi",
"Fungus species"
] |
72,107,334 | https://en.wikipedia.org/wiki/Makatoxin-3 | Makatoxin-3 (a.k.a. MkTx-3, MKTX III or Makatx III) is an α-like scorpion neurotoxin found in the venom of Olivierus martensii. Makatoxin-3 both enhances the activation and slows down the inactivation of voltage-gated NaV1.7 channels, resulting in hyperexcitability of the neurons involved in pain perception.
Source
Makatoxin-3 is a neurotoxin that can be found in the venom of the scorpion Olivierus martensii, also known as Buthus martensii Karsch (BmK) or the Chinese Scorpion. This scorpion is also commonly known as the Chinese scorpion, as it is widely found in China, as well as Korea and Mongolia. Makatoxins account for approximately 4% of the total BmK venom protein. After high temperature processing of the venom, Makatoxins make up 0.8% of the total protein.
Chemistry
Makatoxin-3 is made up of 85 amino acid residues, 19 of which make up the signal peptide at the N-terminal, and four disulfide bonds. It has a high sequence homology (90% identity) with two other toxins from the same Makatoxin protein family, Makatoxin-1 and Makatoxin-2.
The full amino acid sequence of Makatoxin-3 is the following (with the mature peptide underlined):
MNYLI VISFA LLLMT GVESG RDAYI AKKEN CTYFC ALNPY CNDLC TKNGA KSGYC QWAGR YGNAC WCIDL PDKVP IRIPG PCIGR
For comparison, the amino acid sequence of Mktx-2 is (again with the mature peptide underlined):
MNYLI VISFA LLLMT SVESG RDAYI ADSEN CTYFC GSNPY CNDLC TENGA KSGYC QWAGR YGNAC WCIDL PDKVP IRIPG PCRGR
Two key residues of Makatoxin-3 have been identified: K9 and R58. Their substitutions K9D and R58A in mutated Makatoxin-3 reduce the efficacy of the toxin to cause pain in mice.
Makatoxin-3 is thermostable, as processing it by high temperature (60 °C) does not affect the bioactivity of Makatoxin-3 despite the protein concentration going down by 50%. Makatoxin-3 is also stable in artificial gastric juice, but not in artificial intestinal juice, so Makatoxin-3 may be protected from enzymatic digestion.
Target and Mode of Action
Makatoxin-3 is an α-toxin that binds to the S3-S4 loops of the voltage sensor domain IV (VSD4) of NaV1.7 in dorsal root ganglion (DRG) neurons. It is a NaV1.7 agonist. Makatoxin-3 has little to no effect on NaV1.1, NaV1.3, NaV1.6, NaV1.8, and NaV1.9 channels.
Makatoxin-3 shows dose-dependent effects on both the activation and the inactivation of NaV1.7. The toxin slows the inactivation kinetics of NaV1.7 currents. The average persistent currents are larger at both low (250 nmol/kg) and high (750 nmol/kg) concentrations due to the incomplete NaV1.7 channel inactivation at depolarized potentials (-45 mV and higher). At high concentration (750 nmol/kg), the curve of the peak current shifts to the left of the hyperpolarization direction, reaching the peak earlier than in the absence of the toxin; the action potential is also prolonged by shifting the steady-state fast inactivation current to hyperpolarization potentials by -9.3 mV. Furthermore, at high concentration (750 nmol/kg), Makatoxin-3 causes NaV1.7 to open at hyperpolarized potential by shifting its voltage-dependent activation curve by -8.6 mV.
Toxicity
Makatoxin-3 evokes pain and allodynia. After injecting 25 nmol/kg, 50 nmol/kg, and 150 nmol/kg of Makatoxin-3 respectively, mice exhibit flinching behavior due to the pain-inducing effect for approximately 30 minutes before diminishing in a dose-dependent manner (the higher the dose, the higher the number of flinches).
Therapeutic use
Interestingly, notwithstanding the pain response induced by the toxin, Makatoxin-3 also shows an analgesic effect in a dose-dependent manner (50 nmol/kg, 150 nmol/kg, and 450 nmol/kg). 450 nmol/kg elicits an 80% reduction of paw-flinch pain behavior in mice when they are intraperitoneally injected with another pain-inducing substance 30 minutes after the Makatoxin-3 injection. However, if the scorpion body is processed by high temperature, it requires an even higher concentration of Makatoxin-3 to elicit the analgesic effect due to the loss of these peptides. A mutant variant of the neurotoxin, Makatoxin-3-R58A, still produces the analgesic effect, but largely loses its pain-inducing effect.
Unlike morphine, which is a strong opioid receptor analgesic with the addictive side effect, the analgesic activity induced by Makatoxin-3 cannot be reversed by naloxone (μ-opioid receptor antagonist). This means that Makatoxin-3 has an analgesic effect that is not dependent on the endogenous opioid system. Therefore, Makatoxin-3 is being studied as a new potential painkiller.
References
External links
Chemistry details:
P56569 · MKTX1_MESMA
Q86BW9 · MKTX2_MESMA
P59853 · MKTX3_MESMA
Scorpion toxins
Neurotoxins
Ion channel toxins | Makatoxin-3 | [
"Chemistry"
] | 1,303 | [
"Neurochemistry",
"Neurotoxins"
] |
72,107,372 | https://en.wikipedia.org/wiki/U24-ctenitoxin-Pn1a | U24-ctenitoxin-Pn1a (or U24-CNTX-Pn1a) is a neurotoxin that is naturally found in the venom of Latrodectus geometricus (L.geometricus). It reduces the inactivation of insect voltage-gated sodium channels. It is also thought to be a cysteine proteinase inhibitor.
Etymology
The term ‘ctenitoxin’ in U24-ctenitoxin-Pn1a refers to toxins found in the venom of spiders from the Ctenidae family. ‘Pn’ is an acronym for Phoneutria nigriventer referring to the genus and species of the animal it was first isolated from. An alternative name for U24-ctenitoxin-Pn1a is “Venom protein PN16C3”.
Source
U24-ctenitoxin-Pn1a is naturally found in the venom of Latrodectus geometricus, often referred to as the brown widow spider or brown button spider. The spider genus Latrodectus is found worldwide in pantropical and subtropical regions and is considered one of the most dangerous spider genera to humans and animals. Its venom contains latrotoxins, which are the main neurotoxins in the venom.
Chemistry
Structure
U24-ctenitoxin-Pn1a is a 128 amino acid protein. The amino acid sequence of the mature protein is:
1 ARPKSDCEKH RESTEKTGTI MKLIPKCKEN SDYEELQCYE DSKFCVCYDK 50
51 KGHAASPIST KVKECGCYLK QKERKDSGRE SAIIPQCEED GKWAKKQLWE 100
101 FNKSCWCVDE KGEQVGKIHH DCDSLKCE 128
The molecular mass of U24-ctenitoxin-Pn1a is 14,778 Da.
Family
U24-ctenitoxin-Pn1a belongs to the ctenitoxin family. Ctenitoxins consist of two repeats of thyroglobulin type I domain (Thyroglobulin type-1 1 and Thyroglobulin type-1 2) and a signal peptide. Based on the presence of the thyroglobulin domains, U24-ctenitoxin-Pn1a and other members of ctenitoxin family, are thought to inhibit the activity of cysteine proteinases.
Ctenitoxins, in general, also inhibit BgNav as well as the arachnid channel of Varroa destructor (VdNav1).
Target and molecular mechanism
U24-ctenitoxin-Pn1a, purified from L.geometricus venom, reduces the inactivation of the insect voltage-gated sodium channels of Blatella germanica (BgNav) and Drosophila melanogaster (DmNav) expressed in Xenopus laevis oocytes.
Toxicity
The neurotoxic peptides of the L.geometricus venom target the voltage-gated ion channels of both vertebrates and invertebrates. The effect of U24-ctenitoxin-Pn1a is in line with the effect of another toxin from the ctenitoxin family, PnTx2-1 (δ-Ctenitoxin-Pn1a). Both of these toxins slow down the inactivation of insect voltage-gated sodium channels; this may lead to paralysis or mortality of the insects.
Therapeutic use
In general, since spider toxins influence the functioning of the nervous system, they are examined as a possible influence for therapeutic leads or bioinsecticides. The function of U24-ctenitoxin-Pn1a on altering ion channel activity has indicated that it can be viewed as a source for bioinsecticidal peptides.
References
External links
UniProt: P84032
Ion channel toxins
Neurotoxins
Spider toxins | U24-ctenitoxin-Pn1a | [
"Chemistry"
] | 844 | [
"Neurochemistry",
"Neurotoxins"
] |
72,107,857 | https://en.wikipedia.org/wiki/Hydrodynamic%20delivery | Hydrodynamic Delivery (HD) is a method of DNA insertion in rodent models. Genes are delivered via injection into the bloodstream of the animal, and are expressed in the liver. This protocol is helpful to determine gene function, regulate gene expression, and develop pharmaceuticals in vivo.
Methods
Hydrodynamic Delivery was developed as a way to insert genes without viral infection (transfection). The procedure requires a high-volume DNA solution to be inserted into the veins of the rodent using a high-pressure needle. The volume of the DNA is typically 8-10% equal to 8-10% of the animal's body weight, and is injected within 5-7 seconds. The pressure of the insertion leads to cardiac congestion (increased pressure in the heart), allowing the DNA solution to flow through the bloodstream and accumulate in the liver. The pressure expands the pores in the cell membrane, forcing the DNA molecules into the parenchyma, or the functional cells of the organ. In the liver, these cells are the hepatocytes. In less than two minutes after the injection, the pressure returns to natural levels, and the pores shrink back, trapping the DNA inside of the cell. After injection, the majority of genes are expressed in the liver of the animal over a long period of time.
Originally developed to insert DNA, further developments in HD have enabled the insertion of RNA, proteins, and short oligonucleotides into cells.
Applications
The development of Hydrodynamic Delivery methods allows an alternative way to study in vivo experiments. This method has shown to be effective in small mammals, without the potential risks and complications of viral transfection. Applications of these studies include: testing regulatory elements, generating antibodies, analyzing gene therapy techniques, and developing models for diseases. Typically, genes are expressed in the liver, but the procedure can be altered to express genes in kidneys, lungs, muscles, heart, and pancreas.
Gene therapy
Hydrodynamic Delivery has been used to insert genes in an effort to combat genetic diseases. Since HD has mainly focused on small mammals such as rodents, its application in humans is limited. Ongoing research is increasing applications in large mammals and future clinical studies. Computer-assisted image-guided techniques allow surgeons to insert the needle or catheter in the precise site, while an automated injection device monitors and adjusts the pressure needed for optimal gene transmission.. With more precise injections, the volume of DNA solution can be reduced to about 1% of the organism's body weight
By using a catheter to conduct the injection, surgeons are able to express genes in organs other than the liver. Placing the catheter in alternate locations allows the DNA solution to reach the target, although genes are still expressed in the liver.
Developing model organisms
Hydrodynamic DNA delivery is a useful tool for creating model systems for human disease. Using this technique, laboratories are able to study genetic diseases in vivo. Studies are able to insert oncogenes into lab animals to study treatments. In addition to gene transfer, HD has also been shown to work in tumor cells. Metastatic cancer cells can be successfully delivered in model organisms in order to study specific cancers.
Alternative non-viral transfection methods
Alternative methods can be used to insert genes into an organism without a viral vector. These can be split into physical and chemical techniques.
Physical methods:
Electroporation
Gene gun
Sonoporation
Microneedle
Magnetofection
Chemical methods:
Cationic lipids
Cationic polymers
Dendrimer-based vectors
Polypeptide-based vectors
Inorganic, polymeric, and lipid nanoparticles
Gemini surfactants
References
Biological concepts | Hydrodynamic delivery | [
"Biology"
] | 752 | [
"nan"
] |
72,107,941 | https://en.wikipedia.org/wiki/Sausage%20Party%3A%20Foodtopia | Sausage Party: Foodtopia is an adult animated television series that serves as a sequel to the film Sausage Party (2016) created by Seth Rogen, Evan Goldberg, Kyle Hunter, and Ariel Shaffir and developed by Kyle Hunter and Ariel Shaffir for Amazon Prime Video. It features the returning voices of Rogen, Kristen Wiig, Michael Cera, David Krumholtz, Edward Norton and Scott "Diggs" Underwood, with Will Forte, Natasha Rothwell, Sam Richardson, and Yassir Lester voicing new characters.
The first season premiered on Amazon Prime Video on July 11, 2024, with a second season currently in development. The series received generally mixed reviews from critics, who praised its voice acting, animation, score, and humor, while others were divided about its controversial political themes, and criticized its writing and characters.
Premise
After standing up to the human race following the events of the film, Frank and his friends establish a safe haven dubbed "Foodtopia". Following a massive flood that destroys their once promised land, they have no choice but to partner with humans to ensure the survival of their race.
Cast
Main
Seth Rogen as Frank Frankfurter, a sausage who discovered and exposed the truth about the "Great Beyond", he later becomes the leader of Foodtopia.
Kristen Wiig as Brenda Bunson, a hot dog bun who is Frank's love interest, she later becomes co-leader of Foodtopia.
Michael Cera as Barry, a small deformed sausage who is one of Frank's friends, he later becomes chief of police seeking lawbreakers at Foodtopia.
Edward Norton as Sammy Bagel Jr., a neurotic Jewish bagel who had a relationship with Lavash. After Lavash's death, he becomes a comedian talk show host for Foodtopia.
Recurring
Will Forte as Jack, a surviving human whom Frank and Brenda kept alive in order to learn about humanity, along with things such as weather, ravenous animals, and politics. Due to becoming an ally of food, he resorts to cannibalism to avoid eating them.
Sam Richardson as Julius, a tyrannical orange who uses his charms and wealth of human teeth to gain followers in order to take over Foodtopia. The character is a parody of Donald Trump, with his name being a play on Orange Julius and Julius Caesar.
Stephanie Beard as Jeri Rice, a tiny grain of rice who is the sole survivor of her family drowning from the flood and has a personal hatred towards Julius, who selfishly left her for dead. Her name is a pun of former NFL wide receiver Jerry Rice.
Scott "Diggs" Underwood as Gum, a Stephen Hawking-esque intelligent but paraplegic wad of chewed gum who wears glasses and has a mechanized wheelchair. He dies after sacrificing himself for the other food during the flood.
David Krumholtz as Kareem Abdul-Lavash, a Middle Eastern lavash who had a relationship with Sammy. He is killed off during the uprising, leaving Sammy devastated.
Yassir Lester as Iced Tea, a glass bottle of iced tea who is one of the recruits of a task force established by Barry in order to stop foods from stealing teeth from other foods. He also became Barry's partner during the task force establishment.
Natasha Rothwell as Rutabaga Ginsberg, a rutabaga who serves as the judge of Foodtopia
André Sogliuzzo as Christopher "Chris" Bologna, a bologna who serves as one of the recruits of Barry's task force and later one of Julius's two enforcers
Jill Talley as Kishka Hargitay, a kishka who serves as one of the recruits of Barry's task force and later one of Julius's two enforcers
Grey DeLisle as Red Lentils, a box of red lentils who had a human tooth stolen by Pops
James Adomian as Pops, an orange-flavored Popsicle who stole a tooth from Red Lentils
Episodes
Production
Development
Rogen had expressed interest in making a sequel to Sausage Party and more animated films aimed for adults. When asked about the possibility of a sequel, Rogen stated: "It's something we talk about, yeah. That's one of the reasons why we took away the [original] ending because we thought, well, if that was the first scene of the next movie it's probably not what you would want it to be, with them just seeing us and finding us basically. But the idea of a live-action/animated movie, like a Who Framed Roger Rabbit?-style hybrid, is also very exciting, mostly because Who Framed Roger Rabbit? is one of my favorite movies of all time."
On October 26, 2022, it was announced that Amazon had ordered a sequel from Point Grey Pictures, Annapurna Television, and Sony Pictures Television the co-writers Kyle Hunter and Ariel Shaffir returning to develop and executive produce the series under their production company Shaffirwhich while some of the cast (including Rogen, who co-wrote, co-produced, and created the film alongside creative partner Evan Goldberg) returning to reprise their roles, along with new members like Will Forte, Natasha Rothwell, Sam Richardson and Yassir Lester.
Animation
Unlike the first film being produced by Nitrogen Studios, now acquired by Cinesite, the animation for the series would be handled by Bardel Entertainment and Stellar Creative Lab as former Blue Sky Studios executive Andrew Millstein, who now runs Annapurna's animation division with Robert L. Baird after its first film Nimona (2023) was released on Netflix, produces with Rogen, Goldberg, James Weaver, Alex McAtee, Megan Ellison and Patrick Chu on the series while co-producer/co-director Conrad Vernon returns as a supervising director.
Release
On May 1, 2024, it was announced that the series would premiere on Amazon Prime Video on July 11, 2024. A second season is currently in development.
Reception
On review aggregator website Rotten Tomatoes, the series holds a 46% approval rating based on 24 reviews with an average rating of 5.7/10. The website's critics consensus reads: "Clean up on aisle three—Foodtopia has plenty of rancid gags to tide over fans of Seth Rogen's sense of humor, but this follow-up can't help but feel like stale leftovers." On Metacritic, which uses a weighted average, the series assigned a score of 54 out of 100 based on 16 critics, indicating "mixed or average reviews".
Notes
References
External links
2020s American adult animated television series
2020s American animated comedy television series
2020s American LGBTQ-related animated television series
2020s American LGBTQ-related comedy television series
2020s American parody television series
2020s Canadian adult animated television series
2020s Canadian animated comedy television series
2020s Canadian LGBTQ-related television series
2020s Canadian LGBTQ-related comedy television series
2024 American television series debuts
2024 Canadian television series debuts
2024 animated television series debuts
American adult computer-animated television series
American adult animated comedy television series
American post-apocalyptic television series
American sequel television series
American English-language television shows
Canadian computer-animated television series
Canadian adult animated comedy television series
Canadian LGBTQ-related animated television series
Canadian parody television series
Canadian English-language television shows
Post-apocalyptic animated television series
Gay-related television shows
Disney parodies
Amazon Prime Video original programming
Animated television shows based on films
Cultural depictions of Stephen Hawking
Parodies of Donald Trump
Food and drink television series
Television shows about talking objects
Animated television series about birds
Fictional crows
Television shows about death
Television shows about sexuality
Works about corruption
Fiction about cannibalism
Animated television series set in California
Animated television series set in shops
Television series by Sony Pictures Television
Animated television series by Amazon MGM Studios | Sausage Party: Foodtopia | [
"Astronomy"
] | 1,604 | [
"Cultural depictions of astronomers",
"Cultural depictions of Stephen Hawking"
] |
72,110,283 | https://en.wikipedia.org/wiki/NGC%204005 | NGC 4005 is a spiral galaxy in the Leo constellation, located close to the border with the Coma Berenices. A faintly-glowing galaxy, its apparent magnitude is 13.0.
The American astronomer Barbara A. Williams in 1986 noted that when observations are made of 23 galaxies centred on NGC 4005, a trend is found along the major axis of the group. The correlation in the group between position and velocity's slope is greatly different from 0. Williams put forward the explanation for this that the group rotates with a period of less than 4 billion years, however other interpretations have been discussed.
It was discovered by William Herschel on 6 April 1785.
Sources
Spiral galaxies
Leo (constellation)
4005 | NGC 4005 | [
"Astronomy"
] | 144 | [
"Leo (constellation)",
"Constellations"
] |
72,110,356 | https://en.wikipedia.org/wiki/NGC%204015 | NGC 4015 is an unbarred lenticular galaxy in the Coma Berenices. It is located between 215 and 220 million light years away. Its visual magnitude is 13.15.
It was first discovered by Danish astronomer John Dreyer on 26 April 1878, and he described it as a "faint object, very small and with a much brighter middle." He also described it in his notes on the accompanying galaxy, PGC 37703, which he described as "a tail north of the nucleus".
Together, NGC 4015 and PGC 37703 comprise Arp 138 in the Atlas of Peculiar Galaxies.
Sources
Unbarred lenticular galaxies
4015
Coma Berenices | NGC 4015 | [
"Astronomy"
] | 141 | [
"Coma Berenices",
"Constellations"
] |
72,110,598 | https://en.wikipedia.org/wiki/Ebola%20misinformation | Multiple conspiracy theories, hoaxes, and quack cures have circulated about ebola viruses, regarding the origin of outbreaks, treatments for ebola virus disease, and preventative measures.
Unproven and disproven treatments
During the Western African Ebola virus epidemic (2013-2016), a number of unproven and fake treatments were marketed online in the United States, including snake venom, vitamin C, "Nano Silver", and various homeopathic and herbal remedies, including clove oil, garlic, and ewedu soup. Gary Coody, national health fraud coordinator for the FDA, described the purveyors of these unproven treatments as "like storm-chasing roofers, who go and try to defraud people after a big storm. Some of them may be making an honest mistake; other companies are trying to rip people off." Coody also said the problem with implausible and unproven remedies is not only that they are unlikely to work, but also that such treatments may lead to patients delaying effective and timely medical care in a hospital setting.
Implausible and disproven methods for preventing Ebola
During the 2014 and 2019 outbreaks, a number of hoax remedies for the prevention of Ebola were spread online. One such common thread was the frequent use of essential oils. There is no evidence that any of these treatments will decrease the risk of Ebola virus infection, and no known plausible mechanisms for such an effect.
Virus origins
During the 2014 outbreak in Liberia, an article in the Liberian Observer alleged that the virus was a bioweapon designed by the US military as a form of population control. Other theories spreading online during the pandemic alleged that the New World Order had engineered the virus to impose quarantines and travel bans to soften an eventual descent into martial law. During a 2019 outbreak in the Democratic Republic of the Congo, rumors spread that the virus was imported to the country for financial gain, or as part of a plot to procure organs for the black market.
References
2014 hoaxes
Alternative medicine
Biological warfare
Communication of falsehoods
Conspiracy theories
Fake news
Health-related conspiracy theories
Misinformation
Pseudohistory
Pseudoscience
Vaccine hesitancy
Ebola in popular culture | Ebola misinformation | [
"Technology",
"Biology"
] | 470 | [
"Biological warfare",
"Health-related conspiracy theories",
"Science and technology-related conspiracy theories"
] |
72,112,048 | https://en.wikipedia.org/wiki/Ddbar%20lemma | In complex geometry, the lemma (pronounced ddbar lemma) is a mathematical lemma about the de Rham cohomology class of a complex differential form. The -lemma is a result of Hodge theory and the Kähler identities on a compact Kähler manifold. Sometimes it is also known as the -lemma, due to the use of a related operator , with the relation between the two operators being and so .
Statement
The lemma asserts that if is a compact Kähler manifold and is a complex differential form of bidegree (p,q) (with ) whose class is zero in de Rham cohomology, then there exists a form of bidegree (p-1,q-1) such that
where and are the Dolbeault operators of the complex manifold .
ddbar potential
The form is called the -potential of . The inclusion of the factor ensures that is a real differential operator, that is if is a differential form with real coefficients, then so is .
This lemma should be compared to the notion of an exact differential form in de Rham cohomology. In particular if is a closed differential k-form (on any smooth manifold) whose class is zero in de Rham cohomology, then for some differential (k-1)-form called the -potential (or just potential) of , where is the exterior derivative. Indeed, since the Dolbeault operators sum to give the exterior derivative and square to give zero , the -lemma implies that , refining the -potential to the -potential in the setting of compact Kähler manifolds.
Proof
The -lemma is a consequence of Hodge theory applied to a compact Kähler manifold.
The Hodge theorem for an elliptic complex may be applied to any of the operators and respectively to their Laplace operators . To these operators one can define spaces of harmonic differential forms given by the kernels:
The Hodge decomposition theorem asserts that there are three orthogonal decompositions associated to these spaces of harmonic forms, given by
where are the formal adjoints of with respect to the Riemannian metric of the Kähler manifold, respectively. These decompositions hold separately on any compact complex manifold. The importance of the manifold being Kähler is that there is a relationship between the Laplacians of and hence of the orthogonal decompositions above. In particular on a compact Kähler manifold
which implies an orthogonal decomposition
where there are the further relations relating the spaces of and -harmonic forms.
As a result of the above decompositions, one can prove the following lemma.
The proof is as follows. Let be a closed (p,q)-form on a compact Kähler manifold . It follows quickly that (d) implies (a), (b), and (c). Moreover, the orthogonal decompositions above imply that any of (a), (b), or (c) imply (e). Therefore, the main difficulty is to show that (e) implies (d).
To that end, suppose that is orthogonal to the subspace . Then . Since is -closed and , it is also -closed (that is ). If where and is contained in then since this sum is from an orthogonal decomposition with respect to the inner product induced by the Riemannian metric,
or in other words and . Thus it is the case that . This allows us to write for some differential form . Applying the Hodge decomposition for to ,
where is -harmonic, and . The equality implies that is also -harmonic and therefore . Thus . However, since is -closed, it is also -closed. Then using a similar trick to above,
also applying the Kähler identity that . Thus and setting produces the -potential.
Local version
A local version of the -lemma holds and can be proven without the need to appeal to the Hodge decomposition theorem. It is the analogue of the Poincaré lemma or Dolbeault–Grothendieck lemma for the operator. The local -lemma holds over any domain on which the aforementioned lemmas hold.
The proof follows quickly from the aforementioned lemmas. Firstly observe that if is locally of the form for some then because , , and . On the other hand, suppose is -closed. Then by the Poincaré lemma there exists an open neighbourhood of any point and a form such that . Now writing for and note that and comparing the bidegrees of the forms in implies that and and that . After possibly shrinking the size of the open neighbourhood , the Dolbeault–Grothendieck lemma may be applied to and (the latter because ) to obtain local forms such that and . Noting then that this completes the proof as where .
Bott–Chern cohomology
The Bott–Chern cohomology is a cohomology theory for compact complex manifolds which depends on the operators and , and measures the extent to which the -lemma fails to hold. In particular when a compact complex manifold is a Kähler manifold, the Bott–Chern cohomology is isomorphic to the Dolbeault cohomology, but in general it contains more information.
The Bott–Chern cohomology groups of a compact complex manifold are defined by
Since a differential form which is both and -closed is -closed, there is a natural map from Bott–Chern cohomology groups to de Rham cohomology groups. There are also maps to the and Dolbeault cohomology groups . When the manifold satisfies the -lemma, for example if it is a compact Kähler manifold, then the above maps from Bott–Chern cohomology to Dolbeault cohomology are isomorphisms, and furthermore the map from Bott–Chern cohomology to de Rham cohomology is injective. As a consequence, there is an isomorphism
whenever satisfies the -lemma. In this way, the kernel of the maps above measure the failure of the manifold to satisfy the lemma, and in particular measure the failure of to be a Kähler manifold.
Consequences for bidegree (1,1)
The most significant consequence of the -lemma occurs when the complex differential form has bidegree (1,1). In this case the lemma states that an exact differential form has a -potential given by a smooth function :
In particular this occurs in the case where is a Kähler form restricted to a small open subset of a Kähler manifold (this case follows from the local version of the lemma), where the aforementioned Poincaré lemma ensures that it is an exact differential form. This leads to the notion of a Kähler potential, a locally defined function which completely specifies the Kähler form. Another important case is when is the difference of two Kähler forms which are in the same de Rham cohomology class . In this case in de Rham cohomology so the -lemma applies. By allowing (differences of) Kähler forms to be completely described using a single function, which is automatically a plurisubharmonic function, the study of compact Kähler manifolds can be undertaken using techniques of pluripotential theory, for which many analytical tools are available. For example, the -lemma is used to rephrase the Kähler–Einstein equation in terms of potentials, transforming it into a complex Monge–Ampère equation for the Kähler potential.
ddbar manifolds
Complex manifolds which are not necessarily Kähler but still happen to satisfy the -lemma are known as -manifolds. For example, compact complex manifolds which are Fujiki class C satisfy the -lemma but are not necessarily Kähler.
See also
Poincaré lemma
Dolbeault–Grothendieck lemma
References
External links
Hodge theory
Complex manifolds | Ddbar lemma | [
"Engineering"
] | 1,615 | [
"Tensors",
"Differential forms",
"Hodge theory"
] |
72,112,092 | https://en.wikipedia.org/wiki/Richard%20O.%20Mines%20Jr. | Richard O. Mines Jr. is an American civil/environmental engineer, academic, and author. He is an emeritus professor of environmental and civil engineering at Mercer University. His research is primarily focused on the activated sludge process and biological nutrient removal processes, with particular emphasis on environmental engineering, water treatment, biosolids treatment, and engineering education.
Mines has authored/co-authored two books, entitled Introduction to Environmental Engineering, and Environmental Engineering: Principles and Practices. He is a Fellow of American Society for Engineering Education (ASEE), a Fellow of American Society of Civil Engineers (ASCE), and Environmental and Water Resources Institute (EWRI) and a Life Member of ASCE.
Early life and education
Mines was born on July 23, 1953, in Hot Springs, Virginia, the eldest of three children born to Mr. and Mrs. Richard O. Mines. His father worked in the hotel management business (The Omni Homestead Resort and the Greenbrier) while his mother was a bank teller. He is a first-generation engineer as well as a first-generation college graduate.
Mines received his bachelor's degree in civil engineering from Virginia Military Institute in 1975. While studying there, he worked for HARZA engineering as a soils technician on the Bath County Pumped Storage Project. During this period, he was enrolled in the Flight Instruction Program (FIP) to earn his single-engine, land, private pilot's license. Upon graduation from Virginia Military Institute, he attended the University of Virginia, and obtained his master's degree in civil engineering in 1976. From 1980 until 1983, he studied at Virginia Polytechnic Institute and State University, and earned a doctoral degree in civil engineering.
Career
Following his master's degree, Mines held appointment as a second lieutenant in U.S. Air Force stationed with the Virginia Air National Guard at Byrd Field in Richmond, Virginia. After his brief service in the Air Force, he began his academic career as an instructor at Virginia Military Institute in 1977. He served there as research assistant at VMI Research Laboratories until 1978, and as an instructor until 1979. In the following year, he joined Virginia Tech as graduate teaching assistant, and served in this position until 1983. He held his next appointment as an assistant professor at the University of South Florida until 1985, and subsequently rejoined Virginia Military Institute as an assistant professor for a year. From 1992 until 1998, he served as an assistant professor in the Department of Civil and Environmental Engineering at the University of South Florida. Following this appointment, he joined Mercer University as an associate professor and program director of environmental engineering and environmental systems in 1998 and was promoted to professor and program director of environmental engineering in 2005. He served there as director of MSE/MS programs and professor of environmental engineering from 2008 to 2017, and as professor of environmental and civil engineering department, and civil engineering startup coordinator from 2017 to 2022. Since 2017, he has been serving there as a civi engineering startup coordinator in school of engineering. In 2021, he held a brief appointment as chair and professor of environmental and civil engineering department, and then, in June 2022, he became emeritus professor of environmental and civil engineering at Mercer University.
Since 1995, Mines has served in several capacities in the ASEE Southeastern Section, such as vice chair of civil engineering division, chairman of civil engineering division, vice chair of instructional division, vice president of instructional unit, secretary of administrative unit, vice president of the administrative unit, president-elect, president, past- president, secretary administrative division, chair administrative division, Miriam-Wiley Award Committee, and chair awards and recognition. He has also been an active member of ASCE since 1975 and was made a Fellow in 2007 and achieved Life Member status in 2018.
Research
Mines has authored more than one hundred publications. His research works span the field of wastewater treatment, with a particular focus on biological wastewater treatment, and engineering and environmental education.
Wastewater treatment
Mines has done significant research on biological wastewater treatment including activated sludge process, and biological nutrient removal processes (BNR). With a design team at Mercer University, he collaborated, and supervised the design of a residential anaerobic digester aimed at preventing food waste, and making energy as well. He has also modeled a BNR activated sludge system which indicated no significant difference between the predicted effluent values and the actual values, and analyzed the influence of temperature on the activated sludge process. In an in-depth review of wastewater collection system, he addressed all aspects of the collection system including wet weather control strategies, the design, and infrastructure modeling, odor control, and highlighted the innovation strategies as well. His research with colleagues evaluated the efficiency of ozonation for acid yellow 17 dye removal provided the evidence of its effectiveness. In the ozonation of synthetic dye wastewater, the efficiency of two empirical models to predict the parameters of color removal, and COD was evaluated. It was determined that ozonation is more effective in removing the acid yellow 17 dye than that of COD, and both the models can predict the process parameters, and ozone utilization. However, when the wastewater inlet properties are not homogenous, care must be taken to measure to removal efficiencies. According to his research focused on assessing the treatment of waste activated sludge with ozonation, and oxidation, it was reported that ozonation is more effective at removing the total solids (TS) and volatile solids (VS) than oxidation. As the contact time of ozonation increased, so did the biodegradability of wastewater. Having researched that, he developed a ten-liter semi-batch bubble column reactor in collaboration with a team of academics, and tested its operation by examining the ozonation of Waste Activated Sludge (WAS). Followed by that, he expanded his research on the design, and operation of a bench-scale ozonation wastewater treatment system by assessing the ozonation of raw industrial wastewater consisting of paper mill effluent and municipal wastewater from a water resource recovery facility (WRRF) in Georgia. After measuring numerous parameters, his research reported that the average COD removal for municipal wastewater was 82%, whereas for industrial wastewater, it was 84%. The average TSS removal was measured for both wastes, and it was noted to be 83%, and 81% respectively. While studying sludge, he has also focused his research on the sludge stabilization that examines the oxidation, and ozonation effectiveness in bench digestion studies. In a 2006 study, his research indicated ozonation to be more effective than oxidation in the 1-L bench-scale digestion study that reported the average removal rate of volatile suspended solids (VSS), and COD for both aerobic digestor, and ozonated digestor. Later on, using 2-L bench-scale digesters it was asserted that ozone is more efficient in removing total solids (TS) than that of oxidation.
Mines has also evaluated oxygen transfer in the activated sludge process. According to his research on oxygen transfer, the actual oxygen uptake rates (AOURs), and the calculated oxygen uptake rates (COURs) based on mass balances indicated a statistically significant difference for the bioreactors operated at low operated dissolved oxygen levels, and high dissolved oxygen levels. In addition to that, he has studied the influence of tank geometry on the oxygen mass transfer coefficient (KLa), and noticed that among the tanks’ shapes of cylindrical, inverted truncated cone, and rectangular reactors, the inverted cone reported the highest KLa values, whereas the rectangular reactor showed the lowest values of KLa.
Regarding BNR, Mines has investigated the potential of the Virginia Initiative Plant (VIP) in the removal of nitrogen and phosphorus from domestic wastewater as well. He has conducted research studies on the biological treatment of wastewater and nitrification at both high and low influent ammonia nitrogen concentrations.
Advances in education
Another line of Mines' research focuses on advances made in environmental sciences and engineering education. Most of his educational research has been featured in the American Society for Engineering Education conference proceedings. Based on the advanced principles, he developed a complete environmental engineering curriculum in 2000. He was also involved in the 2010 service-learning program of Mercer University which focused on the water availability, and quality in a Kenyan community. The research concluded that a biological sand filter (BSF) is an effective mode of water treatment, and given the limited resources, the project's impact on the undergraduate learning program was considered significant. According to his research on the "inverted classroom" pedagogy, students preferred a hybrid teaching model that features both traditional lecture-based method and inverted pedagogy as well. However, it was shown that the results of subject study were dependent on the students' maturity and their self-motivation to become life-long learners. Another research study, described how the students in an engineering design course indicated their preference of digital story telling of design such as unit operations, and processes of water treatment plant in place of a term paper.
Environmental Engineering: Principles and Practice was reviewed by academics, Alfons G. Buekens, and Luc Hens who wrote that "in summary, this textbook on Environmental Engineering: Principles and Practice can be recommended to all teachers with responsibility in environmental engineering. It focuses upon problem solving, introducing statistical analysis, examples with US and SI units, water and wastewater treatment design, sustainability, public health. It offers all major topics of an US environmental engineering curriculum with clear preference for wide-ranging knowledge on the one hand, water treatment on the other."
Personal life
Mines is married to Beth Ellen Pehle, and has two children. They have been members of Martha Bowman Memorial United Methodist Church.
Mines has completed 56 marathons in 25 states and run over 85,000 miles. He was inducted into the Bath County Athletic Hall of Fame in 2007.
Awards and honors
2001 - Fellow, National Teaching Effectiveness Institute
2002 - Faith in Vocations Fellow, Baylor University
2002-03 - Outstanding Zone II Campus Representative Award, ASEE
2003-04 - Outstanding ASEE Campus Rep Award for Southeastern Section
2003-04 - Outstanding ASEE Zone II Campus Representative Award
2007 - Bath County High School (VA) Athletic Hall of Fame Inductee
2007 - Fellow, American Society of Civil Engineers
2008 - Evaluator of Tennessee Tech Master's Program in Civil & Environmental Engineering
2008 - Commons Fellow, Mercer University
2010 - Fellow, Mercer on Mission to Malawi, Africa
2011 - Tony Tilmans Section Service Award, ASEE Southeastern Section
2013 - Fellow, Environmental and Water Resources Institute
2015 - Fellow, American Society for Engineering Education
2018 - Life Member, American Society of Civil Engineers
2022 - Georgia Engineer of the Year, Georgia Society of Professional Engineers
Bibliography
Books
Introduction to Environmental Engineering (2009) ISBN 9780495295839
Environmental Engineering: Principles and Practice (2014) ISBN 9781118801451
Selected articles
Chandra, S., Mines, R. O., & Sherrard, J. H. (1987). Evaluation of oxygen uptake rate as an activated sludge process control parameter. Journal (Water Pollution Control Federation), 1009–1016.
Mines Jr, Richard O. (1996). Assessment of AWT Systems in Tampa Bay Area, Journal of Environmental Engineering, 122(7), 605–611.
Mines Jr, R. O., Vilagos, J. L., Echelberger Jr, W. F., & Murphy, R. J. (2001). Conventional and AWT mixed-liquor settling characteristics. Journal of Environmental Engineering, 127(3), 249–258.
Lackey, L. W., Mines Jr, R. O., & McCreanor, P. T. (2006). Ozonation of acid yellow 17 dye in a semi-batch bubble column. Journal of Hazardous Materials, 138(2), 357–362.
Mines, R. O., Lackey, L. W., & Behrend, G. H. (2007). The impact of rainfall on flows and loadings at Georgia's wastewater treatment plants. Water, air, and soil pollution, 179(1), 135–157.
Mines Jr, R. O., Northenor, C. B., & Murchison, M. (2008). Oxidation and ozonation of waste activated sludge. Journal of Environmental Science and Health, Part A, 43(6), 610–618.
Mines Jr, Richard O. (2019). Oxygen Transfer Parameters and Oxygen Uptake Rates Revisited, Journal of Environmental Science and Health, Part A, 55(4), 345–353.
References
1953 births
American civil engineers
Environmental engineers
Mercer University faculty
People from Hot Springs, Virginia
Virginia Military Institute alumni
University of Virginia alumni
Virginia Tech alumni
Virginia National Guard personnel
United States Air Force officers
Virginia Military Institute faculty
University of South Florida faculty
American Society of Civil Engineers
Living people | Richard O. Mines Jr. | [
"Engineering"
] | 2,633 | [
"American Society of Civil Engineers",
"Civil engineering organizations"
] |
72,113,961 | https://en.wikipedia.org/wiki/Jayaraj%20Rajagopal | Jayaraj Rajagopal (born 1969) is an Indian-American physician-scientist. He is the Bernard and Mildred Kayden MGH Research Institute Chair and Professor of Medicine at Harvard Medical School. He founded and serves as the Chief of the Stanbury Physician-Scientist Pathway at the Massachusetts General Hospital Department of Medicine. His laboratory focuses on epithelial biology, lung stem cell biology, regenerative biology, and lung diseases.
Education and training
Rajagopal received his undergraduate degree summa cum laude in biochemical sciences from Harvard College, with Hoopes and Henderson Prizes for his work with Jack Szostak and Jennifer Doudna concerning the mechanism of ribozyme catalysis. He then received his MD degree from Harvard Medical School and trained in Internal Medicine at Massachusetts General Hospital, where he served as Chief Medical Resident and completed subspecialty training in Pulmonary and Critical Care Medicine. After finishing his medical training, he joined Doug Melton's laboratory for postdoctoral studies. While there, he began his work studying the development of the lung.
Research
Rajagopal's research centers on the use of stem cell biology and developmental biology to reframe the cellular basis of lung physiology and disease. He, alongside Darrell Kotton, described the first protocols to direct the differentiation of pluripotent stem cells to airway epithelium. His laboratory then made a fundamental contribution to the field of cellular plasticity when he discovered that a fully mature functional murine or human cell can durably dedifferentiate into a stem cell. His lab also demonstrated that a stem cell can serve as a niche for its own daughter cells, extending the fundamental concept of the niche first described by Ray Schofield. He and Aviv Regiv discovered pulmonary ionocytes and airway hillocks by marrying developmental and computational biology through the use of single cell sequencing technology.
Select honors and awards
Outstanding Young Investigator Award, International Society for Stem Cell Research (2016)
Howard Hughes Medical Institute Faculty Scholars Award, Howard Hughes Medical Institute (2016)
MGH Research Scholar Award, Massachusetts General Hospital (2014)
Robertson Investigator Award, New York Stem Cell Foundation (2014)
Maroni Research Scholar Award, Massachusetts General Hospital (2014)
Martin Research Prize for Fundamental (Basic) Research, Massachusetts General Hospital (2014)
Lawrence J. Henderson Prize in Biochemical Sciences, Harvard College (1990)
Thomas T. Hoopes Prize for Outstanding Scholarly Work or Research, Harvard College (1990)
References
Harvard College alumni
1969 births
Living people
Harvard Medical School alumni
Stem cell researchers
Harvard Medical School faculty
American medical researchers
American medical academics
American oncologists | Jayaraj Rajagopal | [
"Biology"
] | 528 | [
"Stem cell researchers",
"Stem cell research"
] |
72,114,025 | https://en.wikipedia.org/wiki/Cl6b | Cl6b (μ-THTX-Cl6b) is a peptide toxin from the venom of the spider Cyriopagopus longipes. It acts as a sodium channel blocker: Cl6b significantly and persistently reduces currents through the tetrodotoxin-sensitive sodium channels NaV1.2-1.4, NaV1.6, and NaV1.7.
Structure
The Cl6b peptide has a molecular weight of 3708.9 Da. It contains 33 amino acid residues, among which six cysteines that engage in three disulfide bonds to form a structural motif known as an inhibitor cystine knot (ICK). This structure grants stability to the toxin and has been identified previously in other spider peptide toxins that share high sequence similarity to Cl6b.
Family
Simultaneously with the isolation of Cl6b, another peptide toxin known as Cl6a was characterized from the same spider species. The two Cl6 peptides share a sequence identity of 78.8%, including the six cysteines that make both peptides adopt the ICK motif.
Target
Cl6b acts as a selective sodium channel blocker.
Source in nature
Cl6b has been isolated from Cyriopagopus longipes, an Asian spider mainly found in Thailand, Cambodia, Laos, and China.
Activity mechanism
Cl6b significantly reduces currents through the tetrodotoxin-sensitive sodium channels NaV1.2, NaV1.3, NaV1.4, NaV1.6, and NaV1.7, with no effect on the tetrodotoxin-resistant sodium channels NaV1.5, NaV1.8, NaV1.9. Cl6b exhibits a particularly high affinity to NaV1.7 channels, which are present in great numbers in nociceptors (pain neurons) located at the dorsal root ganglion. The activity of Cl6b on NaV1.7 has similar characteristics compared to previously reported NaV1.7-peptide inhibitors, such as HWTX-IV., as Cl6b binds to the domain II segments three and four, which are part of the domain's voltage sensor. The binding is high-affinity (half-maximal inhibitory concentration (IC50) 18.80 ± 2.4 nM). It is also irreversible, which poises it as a candidate for the development of long-term in-vivo analgesia.
References
Neurotoxins
Spider toxins
Sodium channel blockers
Ion channel toxins | Cl6b | [
"Chemistry"
] | 531 | [
"Neurochemistry",
"Neurotoxins"
] |
72,114,296 | https://en.wikipedia.org/wiki/Thermal%20Science | Thermal Science is a peer-reviewed open-access scientific journal founded in 1997 and published by Vinča Institute of Nuclear Sciences. The journal is focused on physics and chemistry, and aims to amplify recent scientific results accomplished in Serbia and Southeast Europe.
The editor-in-chief is Vukman Bakić (Vinča Institute of Nuclear Sciences, Serbia) and Editor-In-Chief Emeritus is Prof Simeon Oka (University of Belgrade, Serbia).
Since beginning of 2021 year, authors need to pay article processing charges, and they retain unrestricted copyrights and publishing rights.
Abstracting and indexing
Since 2007 year, the journal is abstracted and indexed in Scopus, and the Science Citation Index Expanded. According to the Journal Citation Reports, the journal has a 2021 impact factor of 1.971.
References
External links
Engineering journals
Academic journals established in 1997
English-language journals
Creative Commons Attribution-licensed journals
5 times per year journals | Thermal Science | [
"Physics",
"Chemistry"
] | 193 | [
"Thermodynamics stubs",
"Physical chemistry stubs",
"Thermodynamics"
] |
72,114,339 | https://en.wikipedia.org/wiki/Juniperic%20acid | Juniperic acid or 16-hydroxyhexadecanoic acid is an omega-hydroxy long-chain fatty acid that is palmitic acid which is substituted at position 16 by a hydroxy group. Palmitic acid is converted to juniperic acid by cytochrome P450 various enzymes, including CYP704B22.
Juniperic acid is a key monomer of cutin in the plant cuticle. It has a role as a plant metabolite.
References
Fatty acids
Hydroxy acids | Juniperic acid | [
"Chemistry"
] | 105 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
72,114,542 | https://en.wikipedia.org/wiki/Pterula%20subulata | Pterula subulata is a species of mushroom producing fungus in the family Pterulaceae. It has the common name angel hair coral.
Taxonomy
It was first described in 1829 by the Swedish mycologist Elias Magnus Fries who classified it as Anthina (Pterula) subulata awaiting the publication of his 1830 text which would formally move it to Pterula subulata.
In 1846 the French mycologist Joseph-Henri Léveillé classified it as Merisma subulatum however this change was not adopted and the current name remains Pterula subulata.
Description
Pterula subulata is a small whitish coral fungus with a delicate branching structure.
Fruit body: 3-6mm thin, hairlike coral that branches repeatedly towards the smooth and shiny pointed tips. The colour is white to off white to light brown with the tips having a lighter colour than the base. Stem: 1-2mm when present but sometimes absent. Flesh: White. Tough and rubbery. Spore print: White. Spores: Ellipsoid and smooth. 5–6 x 2.5–3.5μm. Taste: Indistinct. Smell: Indistinct.
Habitat and distribution
This species is not commonly recorded in the United Kingdom but has been found in Bedfordshire, Cambridgeshire and South Somerset and was observed growing on soil in damp woodland.
It is found on soil in damp woodland where it grows solitary or in small trooping groups probably all through the year.
, GBIF has fewer than 200 recorded observations for this species with most being from Europe. However many of these observations are from iNaturalist and other citizen science platforms so may not be verified and could have been mistaken for another Pterula species.
Etymology
The specific epithet subulata derives from the Latin subulatus meaning awl or needle shaped.
Similar species
Pterula multifida is described very similarly.
References
Pterulaceae
Fungi described in 1830
Fungi of Europe
Fungus species | Pterula subulata | [
"Biology"
] | 400 | [
"Fungi",
"Fungus species"
] |
72,114,645 | https://en.wikipedia.org/wiki/112%20Herculis | 112 Herculis is a binary star system in the northern constellation of Hercules. It is dimly visible to the naked eye with a combined apparent visual magnitude of 5.43. The secondary component is about two magnitudes fainter than the primary star. The distance to this system is approximately 415 light years based on parallax measurements. It is drifting closer to the Sun with a radial velocity of −20 km/s.
The binary character of this system was discovered by W. F. Meyer in 1926. By measuring the variation in velocity of the primary component, he determined an orbital period of 6.3624 days. K. Osawa in 1959 found a stellar classification of A4 III for the pair. W. P. Bidelman observed that the primary has unusually strong lines of ionized phosphorus, and it was assigned to the class of peculiar manganese stars by W. L. W. Sargent and L. Searle in 1962, with a resulting spectral type of B9. No evidence was found for a strong magnetic field by P. S. Conti in 1970.
In 1969, A. Cowley and associates found a stellar class of B9p Hg for this system, indicating a peculiar star with an abundance anomaly of mercury. C. E. Seligman in 1970 determined a mass ratio of 2.06 for the pair, which supported individual stellar classes of B7V and A3V for main sequence components. The sharpness of the spectral lines suggested that at least the primary is rotating synchronously with its orbital period. A more detailed analysis by Seligman and L. H. Allen later in 1970 refined the classifications to B6.5V and A2V. The elemental abundances for both stars appeared similar, although the secondary abundances were more uncertain.
In 1975, the primary was classified as a mercury-manganese star by C. R. Cowley and G. C. L. Aikman. T. A. Ryabchikova and associates in 1996 refined the mass ratio to 1.98. The primary showed significant deficiencies of helium and mercury, but a large overabundance of iron. The secondary component displayed abundances similar to an Am star. This is a double-lined spectroscopic binary system with an orbital period of 6.36246 days and an eccentricity (ovalness) of 0.11. As of 2021, measurements by the TESS space telescope show a rotation period of 12.4 days for the primary, suggesting that it is not rotating synchronously with its orbit. Some variability in flux was recorded by TESS, but this is due to orbital motion – the stars themselves do not appear to be variable.
References
Mercury-manganese stars
Am stars
Spectroscopic binaries
Hercules (constellation)
7113
Durchmusterung objects
Herculis, 112
174933
92614 | 112 Herculis | [
"Astronomy"
] | 586 | [
"Hercules (constellation)",
"Constellations"
] |
72,115,075 | https://en.wikipedia.org/wiki/Antoinette%20Maniatty | Antoinette M. Maniatty (born 1965) is an American materials scientist whose research involves the mechanical properties of materials. She has particularly studied elasticity, fatigue, and cracking in the aluminum alloys used in aircraft. She is a professor and department chair in the Department of Mechanical, Aerospace and Nuclear Engineering at the Rensselaer Polytechnic Institute.
Early life and education
Maniatty was born in 1965 in Cincinnati, and grew up in Allentown, Pennsylvania, where she went to Parkland High School. She became an undergraduate at the Rensselaer Polytechnic Institute, where she majored in mechanical engineering, graduating summa cum laude in 1987. After earning a master's degree in 1988 from the University of Minnesota, under the supervision of Nicholas Zabaras, she attended Cornell University, where she earned a second master's degree in 1990 and completed her Ph.D. in 1991. Her dissertation, Eulerian elasto-viscoplastic formulation for modeling steady-state deformations with strain-induced anisotropy, was supervised by Paul Dawson.
Career
After a year as a visiting lecturer in South Africa at the University of Natal, she returned to the Rensselaer Polytechnic Institute as Clare Boothe Luce Assistant Professor in 1992. She was promoted to associate professor in 1998 and full professor in 2005.
Recognition
Maniatty was named as an ASME Fellow in 2005.
References
External links
Home page
1965 births
Living people
Scientists from Cincinnati
American materials scientists
Women materials scientists and engineers
Rensselaer Polytechnic Institute alumni
University of Minnesota alumni
Cornell University alumni
Rensselaer Polytechnic Institute faculty
Fellows of the American Society of Mechanical Engineers
Parkland High School (Pennsylvania) alumni | Antoinette Maniatty | [
"Materials_science",
"Technology"
] | 333 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
72,115,476 | https://en.wikipedia.org/wiki/DNA%3A%20The%20Story%20of%20Life | DNA: The Story of Life is a four-part Channel 4 documentary series on the discovery of DNA, broadcast in 2003.
The series was broadcast to celebrate fifty years since the 1953 discovery. The first episode was broadcast on Saturday March 8, 2003 at 7pm.
Episodes
Episode 1 - The Secret of Life
It covered the discovery of DNA in 1953. Maurice Wilkins and his involvement with the Manhattan Project, speaking in his university office in London; Linus Pauling's son Peter, of Caltech, now lived in Wales; Linus Pauling approached the discovery of the structure of DNA in a much more methodical rigid manner, perhaps in a plodding way, and Pauling was never one to take the same un-thought-through reckless gambles that Watson and Crick would take; but those ambitious reckless gambles of Watson and Crick would find the structure of DNA; the 1974 BBC documentary The Race for the Double Helix; Watson attended a lecture on the latest X-ray data on DNA at Somerset House in London in November 1951, with the project in Cambridge later producing their first DNA model on 28 November 1951; Sir John Randall, head of the London project, telephoned Lawrence Bragg in Cambridge, with his displeasure at how Watson and Crick had borrowed London's DNA structure X-ray data, which resulted in Watson and Crick being chastened, and removed from their work on DNA structure at Cambridge; but at the London project, events were being often undermined by frosty wooden relationships, and a complete lack of human empathy, as believed Raymond Gosling; at Cambridge, biochemist Erwin Chargaff, of Columbia University, had dinner with Watson and Crick, and although he largely disliked the pair, he explained his Chargaff's rules to them, where equal amounts of adenine and thymine had been found, which had applied to all living cells; Linus Pauling writes to Wilkins, asking for recent X-ray photographs, but is unlucky; on 6 May 1952, the London project takes Photo 51, which indicated a helix structure; in December 1952, Linus Pauling produced his first rudimentary model of DNA, but it was not at all similar to DNA; Watson travelled to the London project again, on 30 January 1953, and whilst looking for any possible photographic X-ray data, Wilkins happily showed him the Photo 51, not realising the dramatic leap in understanding that this photo may have provided for Watson, who himself couldn't believe his luck; Wilkins was not disappointed that Watson had viewed this picture, as he was looking for more scientific collaboration anyway, anywhere that he could find it; in early 1953, Watson and Crick could again resume their DNA project at Cambridge, as Lawrence Bragg realised the need to find the structure before Pauling could discover it; Watson sees the hydrogen bonds between the DNA base pair structure; Watson was later the Director of Cold Spring Harbor Laboratory, and Crick later worked in computational neuroscience.
Episode 2 - Playing God
The advances in genetic engineering. Herb Boyer studied bacteria in a California hospital; one morning he found a bacteria that could splice DNA, with enzymes (a restriction endonuclease); in March 1973 Boyer and Stanley Norman Cohen worked on an experiment to put a toad gene into a bacteria; the experiment worked, and the bacteria cell produced toad proteins; Paul Berg, of Stanford University was attempting to splice cancer genes with bacteria (E.coli) genes; one of his PhD students gave a talk about her work, in a group with Bob Pollack, of Columbia University, in attendance, who thought that such an experiment was unethical; Berg halted his work on genetic engineering, to examine any risks; the four-day Asilomar Conference on Recombinant DNA was held in February, in California, to look at possible risks; Alexander Capron of the University of Pennsylvania, who attended the conference; Jim Watson equated the caution to the risk, to communism; Sydney Brenner, of the University of Cambridge, to prove that the risk was low, himself drank genetically modified bacteria, mixed with milk; scientists would work in biosafety level 4 laboratories; Bob Swanson contacted Herb Boyer, to form a company - Genentech; Walter Gilbert of Harvard University wanted to make synthetic insulin; David Goeddel joined Genentech, and chose to build the insulin molecule step by step; Gilbert was banned from Harvard, so moved to England to work at a biosafety P4 laboratory at Porton Down in Wiltshire, to find the insulin gene; due to cross-contamination, but, after two years of work, he had found the gene of rat insulin instead; Genentech were the first to make synthetic insulin in bacteria; no Nobel prizes were awarded for the important genetic engineering discovery by Herb Boyer and his team; David Ebersman of Genentech.
Plant biologist Rob Horsch, whose father James Robert Horsch was an electrical engineer on the Apollo programme, wanted to modify crop genes, so approached Monsanto, working in a modest laboratory, at the Chesterfield Village Research Center in Chesterfield, Missouri, on Agrobacterium tumefaciens on petunia plants; he next worked on a genetically modified potato, first growing one on 2 June 1987; after proving it could be done, Horsch worked on cotton, more on the potato, wheat, soya, corn, and rice, to give pest resistance; current work includes crops with more vitamins.
Episode 3 - The Human Race
The 1990s and the start of human genome project. Sir Alec Jeffreys, and his discovery on 17 September 1984 at the University of Leicester Department of Genetics, and how his wife Sue thought of possible applications; the Colin Pitchfork case in 1988; Fred Sanger FRS, of the MRC Laboratory of Molecular Biology, and reading the nucleotide sequence; he found a method by chemical markers, which attached to the different nucleotides; Sanger found the 5,000 nucleotide-sequence of a virus, after four years; Sanger invented DNA sequencing; Jeffreys found the portion (minisatellites) of human DNA where that same DNA sequencing, of Fred Sanger, could be best applied; but the human DNA sequence had around 3 billion nucleotide base pairs.
Jim Watson invited scientists to a meeting, in 1986, to discuss possibly sequencing the human genome; David Botstein was against any sequencing, but physicist Walter Gilbert was for the genome sequencing, estimating that it would cost £3bn over 30 years, and one scientist could sequence around 100,000 base pairs in one year; the US Congress approved the project funding in 1990, after Jim Watson put the case; Francis Collins took over the project from 1992; the repeated parts of the DNA sequence, that Alec Jeffreys found, could divide the human genome DNA up into parts, so that sixteen laboratories, around the world, sequenced one separate region, to finish in 2005; one third of the human genome would be sequenced at the Sanger Centre (now the Wellcome Sanger Institute) in South Cambridgeshire, headed in the UK by Sir John Sulston; by 1998, one-third had been sequenced, but Craig Venter thought that progress was much too slow, and would be quicker with shotgun sequencing, and computer reading of the sequence of bases; Leroy Hood of the Institute for Systems Biology, with Michael Hunkapiller of Applied Biosystems; on 10 May 1998, Venter announced that he would go it alone, as he thought that he could complete it by 2001; Venter was met by a torrent of verbal abuse from Jim Watson, at a meeting, who thought that the idea of a private company holding the DNA information was completely unacceptable; Venter had 300 DNA sequence-reading robots made, for his Celera Genomics company, which read DNA from five people, run by Tony White; Jim Watson returned to the US Congress to get more funding, and the public project bought £300,000 DNA sequencing machines from Celera.
With the new machines, 4 million base pairs could be sequenced, by one laboratory, in one day; a main sequencing operation was at the Whitehead Institute at MIT, run by mathematician Eric Lander; Greek scientist Aristides Patrinos, who arranged for Collins and Venter to socially meet; the two sides agreed to make a joint announcement on 26 March 2000; software developers Jim Kent, for the public project, and Gene Myers, for Celera, had to reassemble the data from the many laboratories; but someone had to work out where the protein gene sequences were, so Ewan Birney FRS at the Sanger Centre in Cambridgeshire developed his Ensembl genome database project (with Tim Hubbard and Michele Clamp), to find the individual genes; 48 hours before the announcement on Monday 26 March, the two teams did not know how many genes that there were; the teams estimated around 38,000; around 25% of the genome was found to be gene deserts, and people shared largely the same DNA data - with only around 1 in 1200 base pairs that differed.
Episode 4 - Curing Cancer
The last episode was broadcast on Sunday 30 March 2003 at 8pm.; Mary-Claire King, of University of California, Berkeley, was puzzled as to why the breast cancer risk appeared to be mostly inherited; it would be the BRCA1 gene; she asked David Botstein, of MIT, for assistance; he looked at the spread of known genetic markers across the chromosomes of generations of families; if the markers were not found right across the generations, that part of the chromosome was not probably causing the BRCA mutation; different families' chromosomes were checked for 173 common genetic markers (known as restriction fragment length polymorphisms), which later led to identifying chromosome 17 in 1990; Mary Claire- King needed family information over many generations; she found it at the Family History Library in Utah, kept in immaculate condition by the Mormons (The Church of Jesus Christ of Latter-day Saints); Mark Skolnick also had looked at the Mormon family trees; in October 1987 Mary Claire-King appealed, on local television networks, for family histories, it would take seventeen years to find the BRCA1 gene; around 600,000 women in the US carried the BRCA1 gene; Barbara Weber of the University of Michigan; Mark Skolnick founded Myriad Genetics, to look for the BRCA1 gene, and his company found the mutation; Per Lønning, of Haukeland University Hospital in Norway, and son of Per Lønning, had collected cancer specimens, for possible later understanding of cancer genetics; David Botstein and Patrick O. Brown, who invented the DNA microarray; Brian Druker of the Oregon Health & Science University Hospital (OHSU), who started researching cancer genetics from 1979, and worked with Novartis to make Imatinib; Michael Wigler, of Cold Spring Harbor Laboratory, was finding cancer-causing genes
Transmission
The series was repeated ten years later on More4.
A fifth part of the series was added to a DVD in 2004, entitled DNA: The Story of the Pioneers Who Changed the World
Production
David Dugan was the producer, with Joe Bini the editor. It was a joint production with WNET.
See also
Timeline of the history of genetics
References
External links
IMDb
2003 British television series debuts
2003 British television series endings
2000s British documentary television series
British documentary television series about science
Channel 4 documentary series
Genetics in the United Kingdom
History of biotechnology
History of genetics
Works about genetics | DNA: The Story of Life | [
"Biology"
] | 2,366 | [
"History of biotechnology"
] |
72,115,591 | https://en.wikipedia.org/wiki/List%20of%20WHO%20fungal%20priority%20pathogens | WHO fungal priority pathogens are groups of pathogenic fungi that the World Health Organization deems in need of global attention.
The list has three priority groups. In decreasing order of concern, they are: critical, high, and medium.
Critical group
Cryptococcus neoformans
Candida auris
Aspergillus fumigatus
Candida albicans
High group
Nakaseomyces glabrata (formerly Candida glabrata)
Histoplasma spp.
Histoplasma capsulatum
Histoplasma capsulatum var. capsulatum
Histoplasma capsulatum var. duboisii
Histoplasma capsulatum var. farciminosum
Histoplasma duboisii
Histoplasma muris
Eumycetoma causative agents, including:
Acremonium falciform
Acremonium kiliense
Acremonium recifei
Aspergillus flavus
Aspergillus nidulans
Cladophialophora bantiana
Cladophialophora mycetomatis
Curvularia geniculata
Curvularia lunata
Cylindrocarpon cyanescens
Exophiala jeanselmei
Falciformispora senegalensis
Fusarium moniliforme
Fusarium solani
Glenospora clapieri
Leptosphaeria senegalensis
Leptosphaeria tompkinsii
Madurella grisea
Madurella mycetomatis
Microsporum audouinii
Microsporum canis
Neotestudina rosatii
Phaeoacremonium parasiticum
Phialophora cyanescens
Phialophora verrucosa
Scedosporium (ex. Pseudoalleschia) boydii
Pyrenochaeta mackinonii
Pyrenochaeta romeroi
Trichophyton rubrum
Zopfia rosatii
Mucorales
includes 13 families, 56 genera, 300 species
Fusarium spp.
see List of Fusarium species
Candida tropicalis
Candida parapsilosis
Medium group
Scedosporium spp., including:
Scedosporium americanum
Scedosporium apiospermum
Scedosporium aurantiacum
Scedosporium boydii
Scedosporium cereisporum
Scedosporium deficiens
Scedosporium dehoogii
Scedosporium desertorum
Scedosporium magalhaesii
Scedosporium minutisporum
Scedosporium prolificans
Scedosporium rarisporum
Scedosporium sanyaense
Lomentospora prolificans
Coccidioides spp., including:
Coccidioides immitis
Coccidioides posadasii
Pichia kudriavzevii (formerly Candida krusei)
Cryptococcus gattii
Talaromyces marneffei
Pneumocystis jirovecii
Paracoccidioides spp., including:
Paracoccidioides americana
Paracoccidioides brasiliensis
Paracoccidioides cerebriformis
Paracoccidioides ceti
Paracoccidioides lutzii
Paracoccidioides restrepoana
Paracoccidioides venezuelensis
References
WHO fungal priority pathogens
WHO fungal priority pathogens
Fungal diseases
World Health Organization | List of WHO fungal priority pathogens | [
"Biology"
] | 694 | [
"Fungi",
"Fungal diseases",
"Lists of fungi"
] |
61,239,754 | https://en.wikipedia.org/wiki/White%20blood%20cell%20differential | A white blood cell differential is a medical laboratory test that provides information about the types and amounts of white blood cells in a person's blood. The test, which is usually ordered as part of a complete blood count (CBC), measures the amounts of the five normal white blood cell typesneutrophils, lymphocytes, monocytes, eosinophils and basophilsas well as abnormal cell types if they are present. These results are reported as percentages and absolute values, and compared against reference ranges to determine whether the values are normal, low, or high. Changes in the amounts of white blood cells can aid in the diagnosis of many health conditions, including viral, bacterial, and parasitic infections and blood disorders such as leukemia.
White blood cell differentials may be performed by an automated analyzera machine designed to run laboratory tests – or manually, by examining blood smears under a microscope. The test was performed manually until white blood cell differential analyzers were introduced in the 1970s, making the automated differential possible. In the automated differential, a blood sample is loaded onto an analyzer, which samples a small volume of blood and measures various properties of white blood cells to produce a differential count. The manual differential, in which white blood cells are counted on a stained microscope slide, is now performed to investigate abnormal results from the automated differential, or upon request by the healthcare provider. The manual differential can identify cell types that are not counted by automated methods and detect clinically significant changes in the appearance of white blood cells.
In 1674, Antonie van Leeuwenhoek published the first microscopic observations of blood cells. Improvements in microscope technology throughout the 18th and 19th centuries allowed the three cellular components of blood to be identified and counted. In the 1870s, Paul Ehrlich invented a staining technique that could differentiate between each type of white blood cell. Dmitri Leonidovich Romanowsky later modified Ehrlich's stain to produce a wider range of colours, creating the Romanowsky stain, which is still used to stain blood smears for manual differentials.
Automation of the white blood cell differential began with the invention of the Coulter counter, the first automated hematology analyzer, in the early 1950s. This machine used electrical impedance measurements to count cells and determine their sizes, allowing white and red blood cells to be enumerated. In the 1970s, two techniques were developed for performing automated differential counts: digital image processing of microscope slides and flow cytometry techniques using light scattering and cell staining. These methods remain in use on modern hematology analyzers.
Overview
The white blood cell differential is a common blood test that is often ordered alongside a complete blood count. The test may be performed as part of a routine medical examination; to investigate certain symptoms, particularly those suggestive of infection or hematological disorders; or to monitor existing conditions, such as blood disorders and inflammatory diseases.
Five types of white blood cells are normally found in blood: neutrophils, lymphocytes, monocytes, eosinophils and basophils. Marked shifts in the proportions of these cell types, as measured by the automated or manual differential, can indicate various health conditions. Additionally, cell types which do not normally occur in the blood, such as blast cells, can be identified by the manual differential. These cell types may be found in blood disorders and other pathological states. The manual differential can also identify changes in the appearance of white blood cells, such as reactive lymphocytes, or features such as toxic granulation and vacuolation in neutrophils. The results of the white blood cell differential are reported as percentages and absolute values. Absolute counts are usually reported in units of cells per microliter (μL) or 109 cells per liter (L). The result are then compared against reference ranges, which are defined by individual laboratories and may vary due to different patient populations and testing methods.
CBC and differential testing is usually performed on venous or capillary blood. Capillary blood draws are generally used for infants and individuals whose veins are difficult to access. To prevent clotting, the sample is drawn into a tube containing the anticoagulant compound ethylenediaminetetraacetic acid (EDTA)., meaning blood that has not been centrifuged.
Types
Manual differential
In a manual differential, a stained blood smear is examined under a microscope and white blood cells are counted and classified based on their appearance. A manual differential is usually performed when the automated differential is flagged for review or when the healthcare provider requests it. If the manual differential shows findings suggestive of certain serious conditions, such as leukemia, the blood smear is referred to a physician (generally a hematologist or pathologist) for confirmation.
Procedure
A blood smear is prepared by placing a drop of blood on a microscope slide and using a second slide held at an angle to spread the blood and pull it across the slide, forming a "feathered edge" consisting of a single layer of cells at the end of the smear. This may be done by hand or using an automated slide maker coupled to a hematology analyzer. The slide is treated with a Romanowsky stain, commonly Wright's stain or Wright-Giemsa, and examined under the microscope. The smear is examined in a systematic pattern, scanning from side to side within the feathered edge and counting cells consecutively. The differential is typically performed at 400x or 500x magnification, but 1000x magnification may be used if abnormal cells are present. Cells are identified based on their morphologic features, such as the size and structure of their nucleus and the colour and texture of their cytoplasm. This allows abnormal cell types and changes in cellular appearance to be identified. In most cases, the microscopist counts 100 white blood cells, but 200 may be counted for better representation if the white blood cell count is high. The manual differential count produces percentages of each cell type, which can be multiplied by the total white blood cell count from the analyzer to derive the absolute values.
The manual differential can be partially automated with digital microscopy software, which uses artificial intelligence to classify white blood cells from photomicrographs of the blood smear. However, this technique requires confirmation by manual review.
Limitations
Because relatively few cells are counted in the manual differential, the variability is higher than in automated techniques, especially when cells are present in low amounts. For example, in a sample containing 5 percent monocytes, the manual differential results could be between 1 and 10 percent due to sampling variation. Additionally, cell identification is subjective and the accuracy depends on the skills of the person reading the slide. Poor blood smear preparation can cause an uneven distribution of white blood cells, resulting in inaccurate counting, and improper staining can impede cell identification. Overall, manual differential counts exhibit coefficients of variation (CVs) ranging from 5 to 10 percent, while automated differential counts of normal neutrophils and lymphocytes have CVs of about 3 percent.
In leukemias and other hematologic malignancies, the lineage and genetic characteristics of white blood cells have important implications for treatment and prognosis, and the microscopic appearance of the cells is often insufficient for accurate classification. In these cases, other techniques such as immunophenotyping by flow cytometry or special staining can be used to definitively identify the cells.
Automated differential
Most hematology analyzers provide a five-part differential, enumerating neutrophils, lymphocytes, monocytes, eosinophils and basophils. Some instruments can also count immature granulocytes and nucleated red blood cells. If a six-part differential is provided, the IG or immature granulocyte category consists of promyelocytes, myelocytes and metamyelocytes. Hematology analyzers measure various properties of white blood cells, such as impedance, light scattering parameters, and staining reactions. This data is analyzed and plotted on a scattergram, forming distinct clusters which correspond to white blood cell types. The analyzer counts many more cells than are counted in a manual differential, resulting in improved precision. If abnormal features or cell populations that the analyzer cannot identify are present, the instrument can flag the results for manual blood smear review.
Procedure
Common techniques used by hematology analyzers to identify cells include light scattering, Coulter counting, and cytochemical staining techniques. Some analyzers also use radiofrequency analysis and monoclonal antibody tagging to identify cells. Staining techniques used in differential analyzers include staining of myeloperoxidase, an enzyme found in cells of myeloid lineage, and nucleic acids, which are found in higher concentrations in immature cells.
A small volume of blood (as low as 150 microliters) is aspirated into the analyzer, where reagents are applied to lyse red blood cells and preserve white blood cells. The sample is diluted and passed into a flow cell, which uses hydrodynamic focusing to isolate single cells for accurate analysis of their properties. Various cellular parameters, such as size, complexity and staining reactions, are measured and analyzed to identify cell populations. Basophils are often quantified using a reagent that lyses the cytoplasm of other white blood cells but leaves basophils intact. Samples that have abnormal results or are suspected to contain abnormal cells are flagged by the analyzer for manual blood smear review.
To ensure that results from the automated analyzer are correct, quality control samples are run at least once per day. These are samples with known results that are most often provided by the instrument manufacturer. Laboratories compare their differential results to the known values to ensure the instrument is operating correctly. A moving average measurement may also be used, in which the average results for patient samples are measured at certain intervals. Assuming that the characteristics of the patient population remain roughly the same over time, the average should remain constant. Large shifts in the average value can indicate instrument problems.
Limitations
When immature or abnormal white blood cells are present, automated differential results may be incorrect, necessitating a manual blood smear review. Overall, 10 to 25 percent of CBC samples are flagged for manual review by the analyzer. Although most abnormal samples are automatically flagged, some may be missed; conversely, analyzers may generate false positive flags when no abnormal cells are present. Hematology laboratories compensate for these issues by requiring a smear review when differential or CBC results fall outside certain numerical thresholds, regardless of the presence of analyzer flags. The sensitivity and specificity of analyzer flagging can be determined by comparing analyzer flags to manual differential results.
The automated basophil count is notoriously unreliable, often underestimating counts in basophilia and producing falsely elevated results in the presence of abnormal cells. The manual differential is therefore considered the reference method for these cells.
Analyzers may count nucleated red blood cells, giant and clumped platelets, and red blood cells containing abnormal hemoglobins (such as Hemoglobin S in sickle cell disease) as white blood cells, leading to faulty differential results. Automated differential counts on aged specimens may be incorrect due to cellular degeneration.
Cell types and result interpretation
Neutrophil Neutrophils are the most common white blood cells in normal adult blood. When stained with a Romanowsky stain, they exhibit a multi-lobed nucleus and pink cytoplasm that contains small purple granules.
The neutrophil count is normally higher in newborns and pregnant women than in other groups. Outside of these conditions, increased neutrophil counts (neutrophilia) are associated with bacterial infection, inflammation, and various forms of physiological stress. Neutrophil counts can become extremely high in response to some infections and inflammatory states, which is termed leukemoid reaction because the high white blood cell count mimics leukemia. Neutrophilia may also occur in myeloproliferative disorders.Neutropenia, meaning a low neutrophil count, may occur as a response to drug treatment (especially chemotherapy) or in certain infections, such as tuberculosis and Gram-negative sepsis. Neutropenia also occurs in many hematologic disorders, such as leukemia and myelodysplastic syndrome, and in a variety of autoimmune and congenital diseases. A neutrophil count below the reference interval may be normal in individuals of certain ethnicities; this is termed benign ethnic neutropenia. Very low neutrophil counts are associated with immunosuppression.
When stimulated by infection or inflammation, neutrophils may develop abnormal features in their cytoplasm, such as toxic granulation, toxic vacuolation and Döhle bodies. These features, which are caused by the release of cytokines, are collectively known as toxic changes.
Lymphocyte Lymphocytes, which are the second most common type of white blood cell in adults, are typically small cells with a round, dark nucleus and a thin strip of pale blue cytoplasm. Some lymphocytes are larger and contain a few blue granules.
Increased lymphocyte counts (lymphocytosis) can be caused by viral infections and may also occur after splenectomy. Children have higher lymphocyte counts than adults. Chronic lymphocytic leukemia presents with an elevated lymphocyte count and abnormal lymphocyte morphology, in which the lymphocytes have extremely dense, clumped nuclei and some cells appear smudged on the blood smear. Low lymphocyte counts (lymphopenia) may be seen in infections such as HIV/AIDS, influenza and viral hepatitis, as well as in protein-energy malnutrition, acute illnesses and drug reactions.
In response to viral infections (especially infectious mononucleosis), lymphocytes may increase greatly in size, developing unusually shaped nuclei and large amounts of dark blue cytoplasm. Such cells are referred to as reactive or atypical lymphocytes and when present they are either commented on or counted separately from normal lymphocytes in the manual differential.
Monocyte Monocytes are large cells with a curved or folded nucleus and finely granulated, grey-blue cytoplasm that often contains vacuoles. Monocytes are the third most common white blood cell after neutrophils and lymphocytes.
Increased monocyte counts (monocytosis) are seen in chronic infection and inflammation. Extremely high monocyte counts, as well as immature forms of monocytes, occur in chronic myelomonocytic leukemia and acute leukemias of monocytic origin. Monocyte counts may be decreased (monocytopenia) in individuals who are receiving chemotherapy as well as those with aplastic anemia, severe burns, and AIDS.
Eosinophil Eosinophils have large orange granules in their cytoplasm and bi-lobed nuclei. They are found in low amounts in normal blood.
Elevated eosinophil counts (eosinophilia) are associated with allergic reactions, parasitic infections, and asthma. Eosinophil counts may be decreased in pregnancy and in response to physiological stress, inflammation or treatment with certain drugs, such as steroids and epinephrine.
Basophil Basophils exhibit large, dark purple granules that often cover the cell's nucleus. They are the rarest of the five normal cell types.
Basophilia and eosinophilia can occur along with other white blood cell abnormalities in chronic myeloid leukemia and other myeloproliferative disorders. An increased basophil count may also be seen in hypersensitivity reactions and after splenectomy. The basophil count may decrease during ovulation, steroid treatment, and periods of physiological stress.
Band neutrophil Band neutrophils are young forms of neutrophils which lack segmentation of the nucleus. These cells, which are identified by manual counting, are found in low numbers in normal adult blood.
A left shift, meaning an increase in band neutrophils or immature granulocytes, can indicate infection, inflammation or bone marrow disorders, although it can also be a normal finding in pregnancy. Some laboratories do not separate bands from mature neutrophils in the differential count because the classification is highly subjective and unreliable.
Immature granulocyte Immature granulocytes are immature forms of neutrophils and other granulocytes (eosinophils and basophils). This classification consists of metamyelocytes, myelocytes and promyelocytes, which may be enumerated separately in the manual differential or reported together as immature granulocytes (IG) by automated methods. Immature granulocytes are normally found in the bone marrow, but not in peripheral blood.
When present in significant quantities in the blood, immature granulocytes can indicate infection and inflammation, as well as myeloproliferative disease, leukemia and other conditions affecting the marrow. IGs may also be increased in steroid use and pregnancy. Chronic myeloid leukemia often presents with a high number of immature granulocytes in the peripheral blood. Abnormal promyelocytes with multiple Auer rods, called faggot cells, occur in acute promyelocytic leukemia.
Blast cell Blast cells are very immature cells that are normally found in the bone marrow, where they develop into mature cells (hematopoiesis) before being released into the blood. They can be identified by their large overall size, deep blue cytoplasm, and large nucleus with fine chromatin and prominent nucleoli.
When seen on the blood smear, blast cells are an abnormal finding and may be indicative of acute leukemia or other serious blood disorders. Rarely, they may be seen in severe cases of left shift. The presence of Auer rods inside blast cells indicates that they are of myeloid origin, which has important implications for leukemia treatment. Other morphologic features can provide information about the lineage of blast cells: for example, myeloblasts tend to be large with distinct nucleoli, while lymphoblasts can be smaller with a denser chromatin pattern. However, these features are not diagnostic, and flow cytometry or special staining is generally used to confirm the lineage.
Other cells Various other abnormal cells may be present in the blood in certain conditions. For example, lymphoma cells may be found on the manual differential in some cases of lymphoma, and in mast cell leukemia, mast cells, which are normally confined to tissue, circulate in the blood. There is a very rare phenomenon called carcinocythemia in which tumour cells are seen on the peripheral blood smear.
History
Before automated cell counters were introduced, cell counts were performed manually; white and red blood cells, and platelets were counted using microscopes. The first person to publish microscopic observations of blood cells was Antonie van Leeuwenhoek, who reported on the appearance of red cells in a 1674 letter to the Proceedings of the Royal Society of London; Jan Swammerdam had described red blood cells some years earlier, but had not published his findings at the time. Throughout the 18th and 19th centuries, improvements in microscope technology such as achromatic lenses allowed white blood cells and platelets to be counted in unstained samples. In the 1870s, Paul Ehrlich developed a staining technique that could differentiate between the five white blood cell types. Ehrlich's stain used a combination of an acidic and basic dye to stain white and red blood cells simultaneously. Dmitri Leonidovich Romanowsky improved on this technique in the 1890s by using a mixture of eosin and aged methylene blue, which produced a wide range of hues that was not present when either of the stains was used alone. This was termed the Romanowsky effect and became the basis for Romanowsky staining, the technique that is still used to stain blood smears for manual differentials.
By the early years of the 20th century, the white blood cell differential had become a common practice in the United States, but difficulties in interpreting the results cast doubt on the test's utility. In 1906, Charles Langdon Gibson introduced the Gibson chart, which compared the total white blood cell count against the neutrophil count to distinguish between "pyogenic" and "non-pyogenic" conditions and to predict the severity of infections. Around the same time, Josef Arneth proposed a system of classifying neutrophils by their number of nuclear lobes – termed the "lobe index" or Arneth count – and established a set of reference ranges for neutrophil lobularity. Arneth's analysis of neutrophil segmentation was later found to have limited clinical significance, but the association of hypersegmented neutrophils with vitamin B12 and folate deficiency remains accepted. in 1912 proposed a different classification of neutrophils, separating them into "myelozyten, jugendliche, stabkernige and segmentkernige" – that is, myelocytes, "juveniles" (metamyelocytes), band neutrophils (sometimes called "stabs"), and mature, fully segmented neutrophils – and remarked on the clinical significance of the neutrophilic left shift in conjunction with the white blood cell count and the presence of toxic changes. Schilling's monograph, Das Blutbild und seine klinische Verwertung (The Blood Picture and its Clinical Significance), was translated into English in 1926, and his neutrophil classification system quickly found acceptance in American laboratories.
The first automated hematology analyzer, the Coulter counter, was invented in the early 1950s by Wallace H. Coulter. The analyzer worked on the Coulter principle, which states that when cells are suspended in a fluid carrying an electric current and passed through an aperture, they cause decreases in current proportional to their volume because of their poor electrical conductivity. The number and magnitude of these decreases can be used to count blood cells and calculate their sizes. The Coulter counter was initially designed for counting red blood cells, but it proved effective for counting white blood cells as well.
After basic cell counting had been automated, the white blood cell differential remained a challenge. Research into automating the differential count began in the 1970s and took two main approaches: digital image processing and flow cytometry. Using technology developed in the 1950s and 60s to automate the reading of Pap smears, several models of image processing analyzers were produced. These instruments would scan a stained blood smear to find cell nuclei, then take a higher resolution snapshot of the cell to analyze it through densitometry. They were expensive, slow, and did little to reduce workload in the laboratory because they still required blood smears to be prepared and stained, so flow cytometry-based systems became more popular, and by 1990, no digital image analyzers were commercially available in the United States or western Europe. These techniques enjoyed a resurgence in the 2000s with the introduction of more advanced image analysis platforms using artificial neural networks.
Early flow cytometry devices shot beams of light at cells in specific wavelengths and measured the resulting absorbance, fluorescence or light scatter, collecting information about the cells' features and allowing cellular contents such as DNA to be quantified. One such instrument—the Rapid Cell Spectrophotometer, developed by Louis Kamentsky in 1965 to automate cervical cytology—could generate blood cell scattergrams using cytochemical staining techniques. Leonard Ornstein, who had helped to develop the staining system on the Rapid Cell Spectrophotometer, and his colleagues later created the first commercial flow cytometric white blood cell differential analyzer, the Hemalog D. Introduced in 1974, this analyzer used light scattering, absorbance and cell staining to identify the five normal white blood cell types in addition to "large unidentified cells", a classification that usually consisted of atypical lymphocytes or blast cells. The Hemalog D could count 10,000 cells in one run, a marked improvement over the manual differential.
By 1977 it was estimated that "at least 200" automated differential analyzers were in use throughout the world. In 1981, Technicon combined the Hemalog D with the Hemalog-8 analyzer to produce the Technicon H6000, the first combined complete blood count and differential analyzer. This analyzer was unpopular with hematology laboratories because it was labour-intensive to operate, but in the late 1980s to early 1990s similar systems were widely produced by other manufacturers such as Sysmex, Abbott, Roche and Beckman Coulter.
See also
Flow cytometry
Cell counting
References
Bibliography
10.1007/978-3-319-20279-2
Blood tests
Hematopathology | White blood cell differential | [
"Chemistry"
] | 5,226 | [
"Blood tests",
"Chemical pathology"
] |
61,239,935 | https://en.wikipedia.org/wiki/BacMet | BacMet is an antimicrobial resistance database. It tracks bacterial genes that give resistance to antibacterial biocides and metals.
BacMet consists of two internal databases. One is a manually curated database of genes with experimentally verified resistance function, while the other database looks at predicted resistant genes. The former's data is compiled from NCBI while the annotations are from UniProt and Gene Ontology. BacMet provides information on the resistant genes, their sequences, and their molecular functions.
The database has over 700 confirmed genes and over 150,000 predicted genes that are organized by molecular function and resistant phenotypes. , BacMet was last updated in March 2018 and is based at the University of Gothenburg in Sweden.
See also
List of antimicrobial resistance databases
References
External links
Website
Antimicrobial resistance organizations
Biological databases | BacMet | [
"Biology"
] | 179 | [
"Bioinformatics",
"Biological databases"
] |
61,240,448 | https://en.wikipedia.org/wiki/C23H34O2 | {{DISPLAYTITLE:C23H34O2}}
The molecular formula C23H34O2 (molar mass: 342.51 g/mol, exact mass: 342.2559 u) may refer to:
Cannabidiol dimethyl ether
Cardenolide
Tetrahydrocannabiphorol
Molecular formulas | C23H34O2 | [
"Physics",
"Chemistry"
] | 76 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,240,539 | https://en.wikipedia.org/wiki/C6442H9966N1706O2018S40 | {{DISPLAYTITLE:C6442H9966N1706O2018S40}}
The molecular formula C6442H9966N1706O2018S40 (molar mass: 144.88 kg/mol) may refer to:
Carlumab
Crenezumab | C6442H9966N1706O2018S40 | [
"Chemistry"
] | 70 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
61,241,535 | https://en.wikipedia.org/wiki/Fastran | Fastran is a computer program for calculating the rate of fatigue crack growth by combining crack growth equations and a simulation of the plasticity at the crack tip.
Fastran models accelerations and retardation and other variable amplitude loading effects in crack growth using a crack closure model. The program uses a strip yield model of the crack tip that was first proposed by D. S. Dugdale to calculate the size of the plastic zone ahead of a crack tip. A series of elastic-perfectly plastic strips (originally 30 strips were used) that model the region both ahead and behind the crack tip is used to keep track of the plasticity produced at the crack tip. As the crack grows, the strips are cut and leave a region of raised plastic material in the crack wake that prevents the complete closure of a crack. This profile of the crack is used to calculate the stress intensity factor level at which the crack tip is fully open. The effective stress intensity factor range is then
which allows the rate of growth for the loading cycle to be obtained from the crack growth equation.
The rate of crack growth is then calculated from
History
Fastran was written in the 1980s by James C. Newman while at NASA and is an acronym derived from NASA FATIGUE CRACK GROWTH STRUCTURAL ANALYSIS. Crack closure was first observed by Wolf Elber as propping open a crack tip resulting in a reduction of the full stress intensity range or crack tip driving force. It was assumed this was due to plasticity at the crack tip preventing the fracture surfaces from fully closing.
A similar program CORPUS was also developed around the same time by A. U. de Koning.
FASTRAN is written in the Fortran programming language.
Features
Geometry factors
The geometry factor relates the far-field stresses to the region near the crack tip. Many standard geometry factors are supplied in the program. These scaling factors allow the calculation of the stress intensity factor from the applied loading sequence using
where is the applied far field stress and is the crack length.
The loading sequence is given as a file of sequential turning points that represent the loading sequence. This in combination with a load factor is used to supply the far-field stress of the given geometry. The load sequence is converted into a series of individual load cycles by a method known as rainflow on the fly which is a modified form of the standard rainflow-counting algorithm.
The closure model has also been used to explain the increase rate of growth seen with small cracks known as the small crack effect.
Crack growth equations
Fastran has a variety of crack growth equations built in along with piece wise linear equations that can be read from file.
Theory
This model allows the calculation of the stress ratio or mean stress effect that gives rise to the increased rate of crack growth at higher stress ratios. Experiments have shown the crack is typically open at . In addition the model is able to predict retardation due to overloads which increase the plastic material in the wake of the crack. It also explains the acceleration due to underloads where the crack growth rate increases following an underload which compresses the crack faces together and reduced the degree of interference lowering .
The onset of plasticity is given by the flow stress whose value typically lies mid-way between the yield and ultimate stresses. The flow stress scaling parameter is used to adjust the flow stress to the degree of restraint experienced at the crack tip. This value reflects the stress state at the crack tip and typically lies between a value of for plane stress and for plane strain. The parameter is also used as an adjustment variable to correct the rate of crack to match test data.
Limitations
Plasticity will be greater in regions of plane stress but Fastran only models the crack as a 2d cross section.
Usage
Fastran has been used in the research community and for maintaining the safe life of aircraft as the C-130 used by the USAF, RAF and RAAF. If forms a component of the crack growth program Nasgro.
References
Fracture mechanics
Scientific simulation software | Fastran | [
"Materials_science",
"Engineering"
] | 794 | [
"Structural engineering",
"Materials degradation",
"Materials science",
"Fracture mechanics"
] |
61,241,986 | https://en.wikipedia.org/wiki/Passenger%20Wi-Fi%20on%20subway%20trains | Passenger Wi-Fi on subway trains is a service provided primarily for wireless internet access for passengers on board subway trains.
Wi-Fi for subway passengers is a standard service provided in the majority of large cities worldwide. Wi-Fi in stations is present in the systems of Hong Kong, London, New York, Moscow, St. Petersburg, Singapore, Tokyo, and Toronto. Delivering high-speed Wi-Fi on underground trains is more complex and requires two radio networks: one which delivers the signal to tunnels and trains (a Trackside Network or TSN), and a Wi-Fi network on board the trains to enable passenger connectivity. Wi-Fi connectivity currently operates on underground trains in Moscow and St. Petersburg in Russia; Seoul in South Korea; Delhi's Airport Express in India; and Guangzhou, Shenzhen, Wuhan, and Shanghai in China.
The first known subway system to install onboard Wi-Fi was the Seoul Metro in 2009. The trackside network was based on WiMAX or WiBro (IEEE 802.16m). Trains were connected to the TSN at a speed of about 30 Mbit/s and the Wi-Fi service was provided only to Korean Telecom (KT) subscribers over a private Wi-Fi network. Later, in 2017, it was announced that the network would be renovated to deliver high-speed Wi-Fi to the general public. High-speed free public onboard Wi-Fi was first introduced by MaximaTelecom in the Moscow Metro in 2013. By the end of 2014, all 12 metro lines were equipped with a 5 GHz TSN delivering up to 150 Mbit/s per train with an average of 80 Mbit/s. The last known deployment was in Guangzhou in 2018, which reportedly features over 400 Mbit/s speed per train.
The fastest onboard network in the world was built in the St. Petersburg metro. It features up to 500 Mbit/s speed per train and was built by MaximaTelecom at the end of 2017.
Available technologies
Wi-Fi on subway trains is typically based on cellular (WiMAX, 3G or LTE) radio networks or private trackside networks in the 5 GHz band. Among these two alternatives, LTE and 5 GHz TSN are the only technologies used in contemporary installations.
There are no reported cases of implementing LTE coverage specifically to deliver passenger Wi-Fi, since LTE itself is sufficient to enable passenger connectivity on moving trains. LTE coverage with leaking cable antennas is also far more expensive than a TSN, costing $100K-500K per km of track (in systems with separated tracks for two directions) compared with $50K-100K per km of track for a TSN, based on reported investments in these networks worldwide.
Therefore, public Wi-Fi on trains can be delivered using existing LTE coverage in tunnels or separately deployed private TSN's.
To deliver onboard Wi-Fi, in addition to ensuring radio coverage in tunnels, the operator has to equip the head cars with radio devices to capture the signal from the tunnels, to install Wi-Fi access points in all train cars and to deploy a wired local-area network (LAN) on board.
LTE-based Wi-Fi
For LTE-based Wi-Fi, LTE routers are commonly installed on both head cars (actually, the head car and the end car). In order to deliver high-speed Wi-Fi, LTE routers must ensure the LTE aggregation functionality, which bonds two or more LTE data channels into one logical channel having a stable (without dead spots) and robust connection up to 150 Mbit/s in off-peak hours.
The main issue here is that LTE networks share their throughput between trains and passengers using LTE on board. During rush hours, LTE networks can be overloaded leading the Wi-Fi service to become unavailable. At least, the throughput can't be guaranteed.
The main advantage of LTE-based Wi-Fi is the relatively low investment required – only the trains need to be equipped. Another benefit – the train operator can introduce the service without any involvement by the subway operator if they are different companies. But this can be the case only if multi-operator LTE coverage is already in place.
LTE-aggregation routers and integrated user experience solutions are offered by multiple companies including leaders such as Icomera, Nomad Digital, Klass Telecom and Passengera.
TSN-based Wi-Fi
TSN-based Wi-Fi is the only reasonable method for guaranteeing reliable, high-speed connectivity for passengers. The TSN itself can be used for multiple applications from passenger connectivity to IoT applications and Communication-Based Train Control (CBTC).
To configure a TSN, a core packet network must be installed across the track. TSN base stations usually operate in unlicensed 5GHz Wi-Fi bands, though other similar bands can be used depending on local regulations. The base stations are installed 250-900m apart and are connected to the core network through fiber or RJ45 ports.
Since the leading solutions by FluidMesh and RADWIN are based on Wi-Fi chipsets, the supported features are relatively similar. However, both use specific proprietary management algorithms to ensure stable hand-over and to increase the average throughput.
To enable connectivity on trains, mobile units or base stations generally should be installed in each head/end car. Since the operating frequency is high, the best way to ensure performance is to install ‘shark’ antennas on top of train cars. Another way is to install flat panel antennas inside the cabin, though contemporary trains usually have metalized glass windows which prevent a 5 GHz signal from passing through at a sufficient signal-to-noise ratio (SNR).
Leading 5 GHz TSN solutions are based on IEEE 802.11ac (WiFi 5) chips and feature more than 800 Mbit/s peak aggregated UL+DL physical throughput with two spatial streams. However, real life throughput is much lower. Achieving actual L2/L3 800 Mbit/s peak throughput in tunnels is only possible with 3 or 4 spatial streams. Unfortunately, it is almost impossible to effectively utilize more than two independent streams in subway environment due to physical constraints of radio signal propagation in tunnels.
Investment and monetization models for TSN
Since LTE-based Wi-Fi is usually a supplemental service provided by a transport operator or a cellular carrier, the common funding model here is direct investment without any monetization.
TSN provides more opportunities for monetization – from passenger Wi-Fi with dramatically better performance than existing LTE networks to IoT services with guaranteed performance for transport operators (CCTV with online access, TV broadcasting, telemetry, CBTC, infotainment, etc.). Therefore, there are cases where private external investments were made into TSN-based passenger Wi-Fi projects such as the Moscow and St. Petersburg metros by Maxima
See also
Passenger Wi-Fi on airplanes
References
Wi-Fi
Subterranean rapid transit | Passenger Wi-Fi on subway trains | [
"Technology"
] | 1,446 | [
"Wireless networking",
"Wi-Fi"
] |
61,242,626 | https://en.wikipedia.org/wiki/Digital%20entertainment | Digital entertainment Industry includes, but is not restricted to, any combination of the following industries (that themselves have a considerable degree of overlap):
digital media
new media
video on demand
video games
interactive entertainment
online gambling
mobile entertainment
social media
streaming services
"Digital entertainment", largely a hard to define marketing term, rests upon entertainment technology and ultimately on the enabling basic technologies computers, Internet/World Wide Web, digital rights management, multimedia and streaming media. Apart from pure entertainment, the term rests upon the observation that already in 2011 in the UK, for example, "nearly half of people’s waking hours are spent using media content and communications services" ("screen time").
Digital entertainment is inextricably connected with digital marketing. People who follow influencers on social media for entertainment will receive a fair share of advertising at the same time. Digital merchandise is distributed with every computer game and popup ads or similar are ubiquitous in the online (gaming) world.
See also
Digital Entertainment Content Ecosystem
Entertainment Software Association
Digital media use and mental health
References
Digital media
Entertainment industry | Digital entertainment | [
"Technology"
] | 215 | [
"Multimedia",
"Digital media"
] |
61,243,032 | https://en.wikipedia.org/wiki/C18H18N6O5S2 | {{DISPLAYTITLE:C18H18N6O5S2}}
The molecular formula C18H18N6O5S2 (molar mass: 462.505 g/mol) may refer to:
Cefamandole
Cefatrizine
Molecular formulas | C18H18N6O5S2 | [
"Physics",
"Chemistry"
] | 62 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,243,072 | https://en.wikipedia.org/wiki/C17H19N5O6S2 | {{DISPLAYTITLE:C17H19N5O6S2}}
The molecular formula C17H19N5O6S2 (molar mass: 453.49 g/mol) may refer to:
Cefcapene
Cefovecin
Molecular formulas | C17H19N5O6S2 | [
"Physics",
"Chemistry"
] | 61 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,243,323 | https://en.wikipedia.org/wiki/Helen%20Pearson%20%28science%20journalist%29 | Helen Pearson is a science journalist, author and Chief Magazine Editor for the journal Nature, where she oversees the journalism and opinion content. She is the author of The Life Project, a book about the British birth cohort studies, a series of longitudinal studies which have tracked thousands of people since their birth.
Education
Pearson obtained a Bachelor of Arts degree in Natural Sciences (Genetics) from the University of Cambridge in 1996. She was awarded her PhD in 1999 from the University of Edinburgh, for research completed at the Medical Research Council Human Genetics Unit. Her PhD thesis was on the role of the gene Pax6 in development of the cortex.
Career
Pearson joined Nature in 2001 as a reporter. She has interviewed and written about many high-profile scientists and academics for Nature including Robert Langer, Lawrence Summers and Joe Thornton. She has written freelance articles in outlets including The Guardian and The Independent.
Pearson's book, The Life Project: The extraordinary story of our ordinary lives was published by Allen Lane in 2016 and is about the British birth cohort studies. The oldest of these studies, the National Survey of Health and Development (NSHD), started in 1946, and the series includes the National Child Development Study, established in 1958, the 1970 British Cohort Study and the Millennium Cohort Study of babies born in 2000-2001. Pearson also included in her book the Avon Longitudinal Study of Parents and Children, also known as Children of the 90s.
Appearances
Pearson has given public lectures and talks at academic venues and literary and science festivals including the Edinburgh International Book Festival, the RSA, London School of Economics and Dartington Way with Words Literary Festival. She gave the keynote public lecture at the British Society for the History of Science conference in 2017.
She has appeared on national and international radio including Radio 4’s Start the Week, and has written about science writing and journalism as a career option for scientists.
In 2017, she gave a TED talk based on her book, The Life Project.
Awards
Pearson’s book, The Life Project was named best science book of the year by The Observer, was a book of the year for The Economist and was longlisted for the Orwell Prize, Highly Commended at the 2017 British Medical Association medical book awards and Highly Commended in the 2016 UK Medical Journalists’ Association Awards.
2013 Winner, Medical Journalists’ Association Award For feature article Coming of Age
2012 Winner Best Feature, Association of British Science Writers Award For feature article Study of a Lifetime
2010 Winner Best Feature, Association of British Science Writers Award For feature article One Gene, Twenty Years
2010 Winner, Wistar Science Journalism Award For feature article One Gene, Twenty Years
Published works
The Life Project
What makes some people happy, healthy and successful – and others not?
Britain’s birth cohort studies are the envy of the world
Lab Girl by Hope Jahren – what a life in science is really like
The lab that knows where your time really goes
Prehistoric proteins: Raising the Dead
Children of the 90s: Coming of Age
Study of a Lifetime
One Gene, Twenty Years
Protein engineering: The fate of fingers
At-Home DNA Tests Are Here, But Doctors Aren't Celebrating
External links
Official website
References
Living people
British science journalists
British women journalists
Women science writers
1973 births | Helen Pearson (science journalist) | [
"Technology"
] | 649 | [
"Women science writers",
"Women in science and technology"
] |
61,243,379 | https://en.wikipedia.org/wiki/Synthetic%20biopolymer | Synthetic biopolymers are human-made copies of biopolymers obtained by abiotic chemical routes. Synthetic biopolymer of different chemical nature have been obtained, including polysaccharides, glycoproteins, peptides and proteins, polyhydroxoalkanoates, polyisoprenes.
Synthesis of biopolymer
The high molecular weight of biopolymers make their synthesis inherently laborious. Further challenges can arise from specific spatial arrangement adopted by the natural biopolymer, which may be vital for its properties/activity but not easily reproducible in the synthetic copy. Despite this, chemical approaches to obtain biopolymer are highly desirable to overcome issues arising from low abundance of the target biopolymer in Nature, the need for cumbersome isolation processes or high batch-to-batch variability or inhomogeneity of the naturally-sourced species.
Examples of synthetic biopolymers obtained by chemical routes
cis-1,4-polyisoprene (synthetic analogue of rubber) and trans-1,4-polyisoprene (synthetic analogue of gutta percha) are obtained by coordination polymerisation using suitable Ziegler-Natta catalysts.
Polyhydroxoalkanoates such as poly(3-hydroxobutyrate), poly(hydroxovaleric acid) etc. obtained by polycondensation and polyaddition. Low-molecular weight polylactide and other polyglycolides can also be obtained by chemical synthesis.
Oligonucleotides and polynucleotides (DNA or RNA) can be obtain by chemical synthesis through a variety of established approaches.
A variety of proteins have been obtained by chemical synthesis. A successful approach relies on native chemical ligation, which achieves the synthesis of proteins by linking shorter unprotected peptides. This strategy allowed to obtain, amongst many others, proteins such as insulin-like growth factor 1, the precursor of Aequorea green fluorescent protein and the influenza A virus M2 membrane protein.
Examples of biopolymers obtained by chemoenzymatic routes
Polyhydroxoalkanoates and polyesters obtained by enzyme-assisted esterification using lipases.
Heparin, heparan sulfate and other glycosaminoglycans and plant glycans.
Polysaccharides such as cellulose, amylose, chitin and derivatives
Natural and non-natural polynucleotides can be successfully obtained by enzyme-assisted synthesis using ligase- or polymerase-based approaches and template-assisted polymerisation.
Human-made biopolymers obtained through approaches that involve genetic engineering or recombinant DNA technology are different from synthetic biopolymers and should be referred to as artificial biopolymer (e.g., artificial protein, artificial polynucleotide, etc.).
Applications of synthetic biopolymers
As their natural analogues, synthetic biopolymers find applications in numerous fields, including materials for commodities, drug delivery, tissue engineering, therapeutic and diagnostic applications.
References
Biomolecules
Polymers | Synthetic biopolymer | [
"Chemistry",
"Materials_science",
"Biology"
] | 650 | [
"Natural products",
"Biochemistry",
"Organic compounds",
"Structural biology",
"Molecular biology",
"Polymer chemistry",
"Polymers",
"Biomolecules"
] |
61,244,353 | https://en.wikipedia.org/wiki/Steiner-Optik | Steiner-Optik (also rendered as Steiner Optics) is a manufacturer of optical equipment for the military, hunting and marine sector. The company is headquartered in Bayreuth, northern Bavaria, and has been part of the Beretta Group since 2008. Steiner manufactures products for the civilian market as well as for the defense industry. Its product range includes binoculars for military and police use, rifle scope sights and spotting scopes for hunting, seafaring, outdoor and ornithology. Every year 200,000 to 250,000 binoculars are produced, of which 80% are exported.
History
The company was founded in 1947 by Karl Steiner, and the first product of the company was the Steinette camera. In 1955, the company changed focus to production of binoculars. In 1965, Steiner was awarded a contract with the West German Bundeswehr, which it supplied with the service binoculars called Steiner 8×30 FERO-D12 Bundeswehr Fernglas (German Army Binoculars) between 1966 and 1972. Steiner was the first company to produce nitrogen-filled binoculars. In 1989, Steiner-Optik received by its own account until then the world's largest order for military binoculars, which included the delivery of 72,000 M22 7×50 binoculars to the US Army. Other innovations by Steiner optics included the first binoculars with bearing compass and the first binoculars with laser protection filters.
Product range
Binoculars
Wildlife
SkyHawk 4.0
Blue Horizons
Safari UltraSharp
Navigator Pro
Commander
Commander Global
Observer
Ranger Extreme
Nighthunter
LRF 1700
Hunting rifle scopes
Ranger
Ranger BC
Nighthunter
Tactical rifle scopes
T5Xi
M series
Red Dot Sights
MRS
MPS
Lasers
DBAL series (including AN/PEQ-15A DBAL-A2)
OTAL series
CQBL-1
SBAL series
Night vision devices
AN/PVS-21
See also
Swarovski Optik
References
External links
www.steiner.de
Optics manufacturing companies
Telescope manufacturers
manufacturing companies of Germany
companies based in Bavaria
Bayreuth | Steiner-Optik | [
"Astronomy"
] | 402 | [
"Telescope manufacturers",
"People associated with astronomy"
] |
61,244,456 | https://en.wikipedia.org/wiki/C2115H3252N556O673S16 | {{DISPLAYTITLE:C2115H3252N556O673S16}}
The molecular formula C2115H3252N556O673S16 (molar mass: 47,750 g/mol) may refer to:
Certolizumab pegol
Lumiliximab
Molecular formulas | C2115H3252N556O673S16 | [
"Physics",
"Chemistry"
] | 76 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,244,979 | https://en.wikipedia.org/wiki/Selda%20Gunsel | Selda Gunsel is a Turkish-American chemical engineer. She is currently president of Shell global solutions and vice president (VP) for global commercial technology at Royal Dutch Shell.
Education
She received her BSc in chemical engineering from Istanbul Technical University and an MSc and PhD in chemical engineering from Pennsylvania State University.
Research and career
She joined Pennzoil as a research scientist in 1986. While at Pennzoil, she undertook several sabbatical assignments in the Tribology Group at Imperial College London to work with Professor Hugh Spikes. During this time she published several papers on antiwear and viscosity modifier lubricant additives. In 2000, she was appointed VP for Technology Development and Innovation at Pennzoil.
She moved to Shell in 2002, and has fulfilled a number of roles including; VP of fuels and engine vehicle technology, general manager (GM) of global products and quality, GM of lubricants technology Americas and GM of global strategic R&D. She was appointed to her current role as VP for global commercial technology in 2017.
She has served as both the president of the Society of Tribologists and Lubrication Engineers (STLE) and as the chairman of the Society of Automotive Engineers (SAE) Lubricants Research Award Board.
In 2013, she was made an honorary professor at the State Key Laboratory of Tribology (SKLT) at Beijing's Tsinghua University. She is a Fellow of the STLE and was awarded the STLE International Award in 2015.
Gunsel was elected as a Member of the US National Academy of Engineering in 2017 for leadership in developing and manufacturing advanced fuels and lubricants to meet growing global energy demand while reducing emissions.
References
Living people
American people of Turkish descent
Year of birth missing (living people)
Penn State College of Engineering alumni
American mechanical engineers
21st-century American women engineers
21st-century American engineers
Members of the United States National Academy of Engineering
Tribologists | Selda Gunsel | [
"Materials_science"
] | 399 | [
"Tribology",
"Tribologists"
] |
61,245,307 | https://en.wikipedia.org/wiki/Protein%20quinary%20structure | Protein quinary structure refers to the features of protein surfaces that are shaped by evolutionary adaptation to the physiological context of living cells. Quinary structure is thus the fifth level of protein complexity, additional to protein primary, secondary, tertiary and quaternary structures. As opposed to the first four levels of protein structure, which are relevant to isolated proteins in dilute conditions, quinary structure emerges from the crowdedness of the cellular context, in which transient encounters among macromolecules are constantly occurring.
In order to perform their functions, proteins often need to find a specific counterpart to which they will bind in a relatively long encounter. In a very crowded cytosol, in which proteins engage in a vast and complex network of attracting and repelling interactions, such search becomes challenging, because it involves sampling a huge space of possible partners, of which very few will be productive. A solution to this challenge requires that proteins spend as little time as possible on each encounter, so that they can explore a larger number of surfaces, while simultaneously making this interaction as intimate as possible, so if they do come across the right partner, they will not miss it. In this sense, quinary structure is the result of a series of adaptations present in protein surfaces, which allow proteins to navigate the complexity of the cellular environment.
Early observations
With the sense with which it is used today, the term quinary structure first appeared in the work of McConkey, in 1989. In his work, McConkey runs 2D electrophoresis gels on the total protein content of hamster (CHO) and human (HeLa) cells. In a 2D electrophoresis gel experiment, the coordinates of a protein depend on its molecular weight and its isoelectric point. Given the evolutionary distance between humans and hamsters, and considering evolutionary rates typical of mammals, one would expect a large number of substitutions to have occurred between hamsters and humans, a fraction of which would involve acidic (aspartate and glutamate) and basic (arginine and lysine) residues, resulting in changes in the isoelectric point of many proteins. Strikingly, hamster and human cells yielded almost identical fingerprints in the experiment, implying that many fewer of those substitutions actually took place. McConkey suggested in that paper that the reason why the proteins of humans and hamsters had not diverged as much he anticipated was that an additional selective pressure must have been related to the many non-specific “interactions that are inherently transient” experienced by proteins in the cytoplasm and which “constitute the fifth level of protein organization”.
Protein interactions and quinary structure
Despite the crudeness of McConkey's experiment, his interpretation of the results have proved to be accurate. Rather than simply being hydrophilic, protein surfaces must have carefully been modulated by evolution and adapted to this network of weak interactions, often called quinary interactions. It is important to note that protein-protein interactions responsible for the emergence of quinary structure are fundamentally different from specific protein encounters. The latter are the result of relatively high-stability binding, often linked to functionally meaningful events –many of which have already been described – while the former are often interpreted as some background noise of physiologically unproductive misinteractions that complicate the interpretation of protein networks and need to be avoided, so that normal cellular functions can proceed.
The transient nature of these protein encounters complicates the study of quinary structure. Indeed, the interactions responsible for this upper level of protein organisation are weak and short-lived, and hence would not produce protein-protein complexes that could be isolated by conventional biochemical methods. Therefore, quinary structure can only be understood in vivo.
In-cell NMR and quinary structure
In-cell NMR is an experimental technique prominent in the research field of protein quinary structure. The physical principle of in-cell NMR measurements is identical to that of conventional protein NMR, but the experiments rely on expressing high concentrations of the probe protein, which should remain soluble and contained in the cellular space; which introduces additional difficulties and limitations. However, these experiments provide critical insights about the cross-talk between a probe protein and the intracellular environment.
Early attempts at using in-cell NMR to study protein quinary structure were hindered by a limitation caused by the very phenomenon they were trying to understand. Many probe proteins tested in these experiments turned out to produce broad signals, near the detection limit of the method, when measured inside cells of Escherichia coli. In particular, these proteins seemed to tumble as if they had molecular weights much larger than those corresponding to their size. These observations seemed to indicate that the proteins were sticking to other macromolecules, which would have led to poor relaxation properties
Other in-cell NMR experiments showed that single amino acid changes of surface residues could be used to consistently modulate the tumbling of three different proteins inside bacterial cells. Charged and hydrophobic residues were shown to have the largest impact in protein intracellular mobility. In particular, more negatively charged proteins would tumble faster in comparison with near-null or positively charged proteins. In contrast, the presence of many hydrophobic residues in the protein surface would slow down protein intracellular tumbling. Protein dipole moment, a measure of charge separation across the protein, was shown to have a significant contribution to protein mobility, where high dipole moments would correlate with slower tumbling.
References
Molecular biology
Protein structure | Protein quinary structure | [
"Chemistry",
"Biology"
] | 1,112 | [
"Biochemistry",
"Protein structure",
"Structural biology",
"Molecular biology"
] |
61,245,573 | https://en.wikipedia.org/wiki/ASME%20QME-1 | ASME QME-1 is a standard maintained by the American Society of Mechanical Engineers that provides the requirements and guidelines for the qualification of active mechanical equipment (QME) whose function is required to ensure the safe operation or safe shutdown of a nuclear facility.
Organization of QME-1
The 2017 edition of QME-1 is organized by the following major sections:
Section QR: General Requirements
Section QDR: Qualification of Dynamic Restraints
Section QP: Qualification of Active Pump Assemblies
Section QV: Qualification Requirements for Active Valve Assemblies for Nuclear Facilities
Standards Committee on Qualification of Mechanical Equipment Used in Nuclear Facilities (QME)
ASME QME-1 is maintained and revised by QME and its associated sub-tier groups using the ASME standards development process. Work activities are delegated to specific subcommittees, as per their established charters.
QME Subcommittee on General Requirements
QME Subcommittee on Qualification of Active Dynamic Restraints
QME Subcommittee on Qualification of Pump Assemblies
QME Subcommittee on Qualification of Valve Assemblies
References
External links
QME Subcommittee on General Requirements
QME Subcommittee on Qualification of Active Dynamic Restraints
QME Subcommittee on Qualification of Pump Assemblies
QME Subcommittee on Qualification of Valve Assemblies
Mechanical standards
ASME standards | ASME QME-1 | [
"Engineering"
] | 241 | [
"Mechanical standards",
"Mechanical engineering"
] |
61,245,736 | https://en.wikipedia.org/wiki/NGC%206778 | NGC 6778 is a planetary nebula (PN) located about 10,300 light years away from the Sun in the equatorial constellation of Aquila. It is positioned 5° to the SSW of the prominent star Delta Aquilae. This nebula was discovered by German astronomer Albert Marth during the period 1863–1865. English astronomer John Herschel may have mistakenly catalogued it as NGC 6785, as nothing can be found now at the coordinates he gave for it. In the New General Catalogue it was described as a "small, elongated, ill-defined disc".
This planetary nebula displays a disrupted morphology, with a roughly S-shaped feature projecting out of an irregular shell, along with linear jet-like forms. The inner part contains a highly distorted elliptical ring oriented along an east-west direction. The nebula and ring have an angular size of and they are about 4,400 years old, while the jets are around 1,700 years old.
At the center of the nebula is a close binary star system with an orbital period of just 3.68 hours, one of the shortest known among the binary central stars that form a planetary nebulae. Their proximity to each other provides strong evidence that they have passed through a common-envelope (CE) phase earlier in their evolution. The pair may now consist of a primary star with , a red dwarf secondary companion having , and a semimajor axis of only .
The surrounding nebula is inclined about 85° to the line of sight from the Earth. The torus of this nebula is notable for its high expansion velocity, measured at up to 60–70 km/s. It displays collimated outflows, possibly as a result of the CE behavior of the central stars or else a short-lived accretion disk. The pair of jets are located along a position angle of 15°, showing fast outflow with radial velocities of around 100 km/s. The nebula is notable for the rich amount of filamentary "low-ionization structures", or LIS, resembling the wispy structures of nova explosions. These too may be the result of the CE interaction.
In addition to a higher than normal helium abundance, the nebula displays unusually strong optical recombination lines from heavier elements; one of the highest known among PNe. These may be the result of a very late thermal pulse, or "final flash", following the initial ejection of the stellar envelope that formed the nebula. The pulse would have ejected chemically-enriched material into the old nebula, changing its abundances.
References
External links
Planetary nebulae
Binary stars
Aquila (constellation)
6778 | NGC 6778 | [
"Astronomy"
] | 546 | [
"Aquila (constellation)",
"Constellations"
] |
61,246,073 | https://en.wikipedia.org/wiki/Charles%20Matcham | Charles Arthur Matcham (15 January 1862 – 22 September 1911) was an English civil engineer and businessman who spent most of his life in America. He founded numerous businesses, mostly within the cement-making industry, in areas including Phillipsburg, in New Jersey, and Allentown, and Portland in Pennsylvania. He was the younger brother of the English theatre architect Frank Matcham.
Life and career
Charles Matcham was born on 15 January 1862 in Torquay, Devonshire. He was the third son of Charles Matcham (1826–1888), a brewer, and his wife, Elizabeth Lancaster (1830–1905). Charles Jr. was educated at schools in Hambledon in Hampshire, and then Brighton, East Sussex.
Matcham entered the engineering industry in 1875 in London where he received an honours mention for his mechanical drawing and designs at the National Art Training School in South Kensington. From 1877–80 he worked as a mechanical draftsman in London. In 1879 he joined the newly-formed American Bell Telephone Company and built telephone exchanges in Europe, including Antwerp, Brussels, and Charleroi. He also worked in St. Petersburg and Riga, where he introduced the newly-invented telephone and installed the Alexander II of Russia's system, personally.
In 1881 Matcham travelled to Chicago, America, where he started work with the Chicago Telephone Company for whom he built exchanges. Three years later he joined the Pennsylvania Telephone Company and became the Chief Engineer and Superintendent. In 1890, along with his brother-in-law, he founded a cement plant in Phillipsburg, New Jersey, called the Whittaker Cement Company. He stayed with the business until its sale in 1897 to the Alpha Portland Cement Company, of which he was manager. That year he established the Lehigh Portland Cement Company where he stayed for 10 years before joining the Allentown Cement Company as general manager. He was a member of the American Society of Civil Engineers, American Institute of Mining Engineers, American Society for Testing Materials, and the National Geographic Society. Through his work within the civil engineering industry, he invented a cement stone pulveriser, for which he owned the patent.
Illness and death
Matcham retired in 1910 after failing health. He died of a chest infection on 22 September 1911 at the age of 49.
Personal life
Matcham married Margaret Ormrod in 1888 and they had three children; a son, Charles, and daughters Dorothy and Catherine. He was the younger brother of the theatre architect Frank Matcham, and Sydney, who was noted for founding the first travel agency in Allentown, called the Matcham Travel Bureau.
Notes and references
Notes
References
Sources
1862 births
1911 deaths
Civil engineers
People from Torquay
Businesspeople from Devon
Engineers from Devon
English emigrants to the United States | Charles Matcham | [
"Engineering"
] | 555 | [
"Civil engineering",
"Civil engineers"
] |
61,247,053 | https://en.wikipedia.org/wiki/Warsaw%20recommendation%20on%20recovery%20and%20reconstruction%20of%20cultural%20heritage | Warsaw recommendation on recovery and reconstruction of cultural heritage is a document from 2018 constituting a comprehensive set of principles concerning the process of urban reconstruction and reconstruction of historic buildings or complexes of buildings destroyed as a result of armed conflicts or natural disasters.
This act of soft law is the result of the international conference, "The challenges of World Heritage recovery", which took place at the Royal Castle in Warsaw on May 8, 2018. During the conference representatives of UNESCO, ICOMOS, ICCROM, World Bank and Global Alliance for Urban Crises met for the first time to discuss problems related to the reconstruction of world heritage sites. Over 200 participants representing all regions of the world attended the meeting.
The provisions of the Warsaw recommendation were subsequently approved in the decision of the UNESCO World Heritage Committee at its 42nd session in Manama, Bahrain (42 COM 7).
The Warsaw recommendation refers to the example and experiences of the reconstruction of Warsaw after World War II. The history of Warsaw and its unique inscription on the UNESCO World Heritage List in 1980 in recognition of the heroism and dedication of the Polish society which has rebuilt the capital city, has become an example for other cities affected by the tragedy of wars and natural disasters.
References
External links
Architectural conservation
Architectural history
Cultural heritage
Conservation and restoration of cultural heritage | Warsaw recommendation on recovery and reconstruction of cultural heritage | [
"Engineering"
] | 256 | [
"Architectural history",
"Architecture"
] |
61,247,455 | https://en.wikipedia.org/wiki/C11H26NO2PS | {{DISPLAYTITLE:C11H26NO2PS}}
The molecular formula C11H26NO2PS (molar mass: 267.37 g/mol, exact mass: 267.1422 u) may refer to:
Chinese VX (CVX)
QL sulfide
VR (nerve agent)
VX (nerve agent) | C11H26NO2PS | [
"Chemistry"
] | 75 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
61,247,823 | https://en.wikipedia.org/wiki/Tandem%20Reconnection%20and%20Cusp%20Electrodynamics%20Reconnaissance%20Satellites | Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) is a planned orbiter mission tasked to study the origins of the solar wind and how it affects Earth. TRACERS was proposed by Craig A. Kletzing at the University of Iowa who served as Principal Investigator until his death in 2023. David M. Miles at the University of Iowa was named as Principal Investigator in his stead. The TRACERS mission received US$115 million in funding from NASA.
Overview
TRACERS is a future mission by NASA that aims to answer long-standing questions critical to understanding the Sun-Earth System. TRACERS is a pair of identically instrumented spinning spacecraft that will study how the Sun's solar wind interacts with the Earth's magnetosphere. TRACERS was initially planned to be launched as a secondary mission to another orbiter named Polarimeter to Unify the Corona and Heliosphere (PUNCH). PUNCH will study the solar wind, a stream of charged particles emanating from the Sun, while TRACERS will study Earth's response.
TRACERS will observe solar particles interacting with Earth's magnetic field at the northern magnetic cusp region. Here, the field lines guide particles from the boundary between Earth's magnetic field down into the atmosphere. In a process known as magnetic reconnection, the field lines violently reconfigure, sending particles out at speeds that can approach the speed of light. Some of these particles will be guided by the Earth's field into the region where TRACERS can observe them. TRACERS will study a longstanding question about where reconnection happens at the magnetopause and how the solar wind affects the place and timing, helping NASA better forecast the influx of energetic particles into Earth's magnetic field that has the potential to disrupt the power grid and satellite communications. TRACERS and PUNCH will work well together with the other existing heliophysics spacecraft.
On 20 June 2019, NASA announced that PUNCH and TRACERS were the winning candidates to become the next missions in the agency's Small Explorer program. On 29 September 2023 NASA Launch Services Program selected SpaceX's Falcon 9 rocket to provide the launch service for TRACERS launch through the Venture-Class Acquisition of Dedicated and Rideshare (VADR) program.
As of October 2023, TRACERS has a target launch readiness date of 13 April 2025.
Instruments
DC Magnetometer (MAG) a fluxgate magnetometer that provides measurements of the background magnetic field up to 5 Hz will be provided by University of California, Los Angeles.
A Search coil magnetometer (MSC) three-axis magnetic search coil to measure AC magnetic field from 2 Hz up to 1 kHz will be provided by University of Iowa.
An Electric Field Instrument (EFI) a two axis electric field experiment to measure electric fields from 1 Hz to 1 kHz.will be provided by University of California, Berkeley.
Analyzer for Cusp Electrons (ACE) an electrostatic analyzer to measure cusp electrons from 40 eV to 10 keV will be provided by University of Iowa.
Analyzer for Cusp Ions (ACI) is an electrostatic analyzer to measure cusp ions from 50 eV to 10 keV.
A technology demonstration, Magnetometers for Innovation and Capability (MAGIC), was added in 2020 with the goal to test prototype magnetic-field instruments.
See also
Heliophysics
Magnetospheric Multiscale Mission
Solar storm
References
External links
Solar space observatories
Proposed space probes
NASA space probes
Explorers Program
2025 in spaceflight
Geomagnetic satellites | Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites | [
"Astronomy"
] | 728 | [
"Space telescopes",
"Solar space observatories"
] |
61,248,076 | https://en.wikipedia.org/wiki/C55H70MgN4O6 | {{DISPLAYTITLE:C55H70MgN4O6}}
The molecular formula C55H70MgN4O6 (molar mass: 907.49 g/mol, exact mass: 906.5146 u) may refer to:
Chlorophyll_b
Chlorophyll_f
Molecular formulas | C55H70MgN4O6 | [
"Physics",
"Chemistry"
] | 75 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,248,231 | https://en.wikipedia.org/wiki/C16H19ClN2 | {{DISPLAYTITLE:C16H19ClN2}}
The molecular formula C16H19ClN2 (molar mass: 274.79 g/mol, exact mass: 274.1237 u) may refer to:
Chlorphenamine, or chlorpheniramine
Dexchlorpheniramine
Molecular formulas | C16H19ClN2 | [
"Physics",
"Chemistry"
] | 75 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
61,248,302 | https://en.wikipedia.org/wiki/C18H12CrN3O6 | {{DISPLAYTITLE:C18H12CrN3O6}}
The molecular formula C18H12CrN3O6 (molar mass: 418.300 g/mol) may refer to:
Chromium(III) nicotinate
Chromium(III) picolinate
Molecular formulas | C18H12CrN3O6 | [
"Physics",
"Chemistry"
] | 69 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
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