id int64 39 79M | url stringlengths 31 227 | text stringlengths 6 334k | source stringlengths 1 150 ⌀ | categories listlengths 1 6 | token_count int64 3 71.8k | subcategories listlengths 0 30 |
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60,861,181 | https://en.wikipedia.org/wiki/Redmi%20K20 | Redmi K20 Pro and Redmi K20 (Xiaomi Mi 9T Pro and Xiaomi Mi 9T globally) are smartphones introduced by the Xiaomi sub-brand Redmi in an event held in China. A Premium variant for the Pro was later revealed, with the Snapdragon 855+, a new 512 GB/12 GB RAM model, a refined cooling system, and an exclusive finish.
Specifications
Design
Redmi K20 Pro comes with a newer kind of gradient design. It resembles firmness, flame, power and mystery at the first look from our artistic point of view.
The Redmi K20 Pro and Redmi K20 ( Xiaomi Mi 9T globally ) are available in four colors: Glacier Blue, Flame Red, Carbon Black and Pearl White. The Redmi K20 Pro and Redmi K20 both have 6.39" full-screen FHD+ Horizon AMOLED displays,103%NTSC, DCI-P3 and a glass/metal construction.
Hardware
The Redmi K20 Pro comes with the Qualcomm Snapdragon 855 paired with 6 GB of RAM with 64 or 128 GB internal storage and 8 GB of RAM with 128 GB or 256 GB of non-expandable internal storage. The Redmi K20 is powered by the mid-range Qualcomm Snapdragon 730 and has the same RAM and storage options as the Redmi K20 Pro. The Redmi K20 Pro has 27W fast charging while the Redmi K20 has 18W fast charging; both have 7th generation in-display fingerprint sensors and 4000 mAh batteries.
Camera
Both smartphones have three rear-facing cameras but K20 Pro has the 48-megapixel Sony Exmor IMX586 as the primary sensor While the K20 has the Sony IMX582, a 13-megapixel ultrawide sensor, and an 8 MP telephoto lens, both with a motorized pop-up 20-megapixel front camera.
The main speciality of the triple 48+8+13 MP back camera is that it comes with a wide, ultrawide and a telephoto lens. It allows you to capture scenes from many different perspectives. 2x optical zoom keeps great details when the photo is zoomed in or cropped.
Software
Both smartphones come with MIUI 10 on top of Android Pie. The Redmi K20 Pro Premium Edition ships with MIUI 11 on top of Android 10.
References
K20
Mobile phones introduced in 2019
Mobile phones with multiple rear cameras
Mobile phones with 4K video recording
Discontinued smartphones | Redmi K20 | [
"Technology"
] | 535 | [
"Mobile technology stubs",
"Mobile phone stubs"
] |
60,866,579 | https://en.wikipedia.org/wiki/Trisporic%20acid | Trisporic acids (TSAs) are C-18 terpenoid compounds synthesized via β-carotene and retinol pathways in the zygomycetes. They are pheromone compound responsible for sexual differentiation in those fungal species. TSAs and related compounds make up the trisporoid group of chemicals.
History
Trisporic acid was discovered in 1964 as a metabolite that caused enhanced carotene production in Blakeslea trispora. It was later shown to be the hormone that brought about zygophore production in Mucor mucedo. The American mycologist and geneticist Albert Francis Blakeslee, discovered that some species of Mucorales were self-sterile (heterothallic), in which interactions of two strains, designated (+) and (-), being necessary for the initiation of sexual activity. This interaction was found by Hans Burgeff of the University of Goettingen to be due to the exchange of low molecular weight substances that diffused through the substratum and atmosphere. This work constituted the first demonstration of sex hormone activity in any fungus. The elucidation of the hormonal control of sexual interaction in the Mucorales extends over 60 years and involved mycologists and biochemists from Germany, Italy, the Netherlands, UK and the USA.
Functions in Mucorales
Recognition of compatible sexual partners in zygomycota is based on a cooperative biosynthesis pathway of trisporic acid. Early trisporoid derivatives and trisporic acid induce swelling of two potential hyphae, hence called zygophores, and a chemical gradient of these inducer molecules results in a growth towards each other. These progametangia come in contact with each other and build a strong connection. In the next stage, septae are established to limit the developing zygospore from the vegetative mycelium and in this way the zygophores become suspensor hyphae and gametangia are formed. After dissolving of the fusion wall, cytoplasm and a high number of nuclei from both gametangia are mixed. A selectional process (unstudied) results in a reduction of nuclei and meiosis takes place (also unstudied until today). Several cell wall modifications, as well as incorporation of sporopollenin (dark colour of spores) take place resulting in a mature zygospore.
Triporic acid, as the endpoint of this recognition pathway, can solely be produced in presence of both compatible partners, which enzymatically produce trisporoid precursors to be further utilized by the potential sexual partner. Species specificity of these reactions is among others obtained by spatial segregation, physicochemical features of derivatives (volatility and light sensitivity), chemical modifications of trisporoids and transcriptional/posttranscriptional regulation.
Biosynthesis
Parasexualism
Trisporoids are also used in the mediation of the recognition between parasite and host. An example is the host-parasite interaction of a parasexual nature observed between Parasitella parasitica, a facultative mycoparasite of zygomycetes, and Absidia glauca. This interaction is an example for biotrophic fusion parasitism, because genetic information is transferred into the host. Many morphological similarities in comparison to zygospore formation are seen, but the mature spore is called a sikyospore and is parasitic. During this process, gall-like structures are produced by the host Absidia glauca. This coupled with further evidence has led to the assumption that trisporiods are not strictly species specific and that trisporiods represent the general principle of mating recognition in Mucorales.
References
Carotenoids
Carboxylic acids | Trisporic acid | [
"Chemistry",
"Biology"
] | 803 | [
"Biomarkers",
"Carboxylic acids",
"Functional groups",
"Carotenoids"
] |
60,869,621 | https://en.wikipedia.org/wiki/Bowing%20in%20Japan | is the act of lowering one's head or the upper part of the torso, commonly used as a sign of salutation, reverence, apology or gratitude in social or religious situations.
Historically, ojigi was closely affiliated with the samurai. The rise of the warrior class in the Kamakura period (1185–1333) led to the formations of many well-disciplined manuals on warrior etiquette, which contained instructions on proper ways to bow for the samurai. The Japanese word (ojigi) was derived from the homophone , which originally meant "the opportune timing to do something". It did not start to denote specifically the act of bowing in the contemporary sense until late Edo period (1603–1868), when samurai bowing etiquette had spread to the common populace. Nowadays, the ojigi customs based on the doctrines of the Ogasawara School of warrior etiquette—which was founded some 800 years ago— are the most prevalent in society.
In modern-day Japan, bowing is a fundamental part of social etiquette which is both derivative and representative of Japanese culture, emphasizing respect and social ranks. From everyday greetings to business meetings to funerals, ojigi is ubiquitous in Japanese society and the ability to bow correctly and elegantly is widely considered to be one of the defining qualities of adulthood. Therefore, even though most Japanese people start bowing at a very young age, many companies in Japan will take the extra effort to specially train their employees on how to bow in business meetings.
Generally speaking, ojigi in Japan can be coarsely divided into two categories: zarei (), bowing while kneeling, and ritsurei (), bowing while standing. In either case, it is considered essential to bend one's body only at the waist and keep one's back completely straight during the bowing gesture. Failure to do so is often thought of as an indication of lethargy, insincerity and even disrespect. Different sub-categories of ojigi vary mainly in the angles of inclination of one's body and the positions of one's hands, which are determined both by the status of the person one is bowing to and the scenario or context of gesture.
History
While there are few official records on how the etiquette of bowing originated in Japan, it is widely believed that it traces its roots back to the propagation of Buddhism to Japan from the kingdoms of ancient China between the 5th and 8th centuries. In Buddhist teachings, bowing is an important gesture of piety and respect. Worshipers bow to Buddha statues in devotion, and disciples bow to their masters in admiration. Such religious etiquette was often believed to be the foundation of ojigi in Japan.
In the Kamakura period (1185–1333), with the appearance of the first feudal military government, the warrior class, or samurai, started playing a more prominent role in Japanese history. The principles and concepts of the warrior class began to shape the cultural standards of the society. Ojigi, along with other forms of samurai etiquette, under the influence of Zen Buddhism, became much more disciplined and widely practiced among the warrior class.
In the subsequent Muromachi period (1336–1573), systematically written manuals on different sects of samurai etiquette, such as the and , were developed to strengthen and promote the cultural identity of the warrior class. These were often considered the first blueprints on proper ways to dress and behave for the samurai. The art of bowing, consequently, also became increasingly complicated and well-established. Different variations of ojigi were to be used for different scenarios, from indoor meetings, to archery matches, to praying at sacred temples. However, the advancement of warrior etiquette came to a halt in the later years of the Muromachi period, which was characterized by social turmoil and unrelenting warfare, popularly known as the Sengoku Era (Age of Warring States; 1467–1600). Formal etiquette was largely abandoned in the times of chaos and cruelty, and customs of ojigi faded in the course of history for over a century.
The establishment of the third and final feudal military government in the Edo period (1603–1868) brought peace and prosperity back to the islands, resulting in the second blooming of samurai etiquette in Japan. Classic customs of the Ogasawara School were revitalized and new schools of disciplines, such as the , mushroomed. In the meantime, stability and burgeoning urban sectors provided common Japanese people with the opportunity for recreation and education. Since the warrior class was put at the top of the social ladder in the new social ranking system under the governance of the Tokugawa Shogunate, warrior etiquette like ojigi became ever more popular and gradually spread to the common people. As a by-product of the strict , the showcasing of social status also became progressively important in ojigi, a trait that is still observable in Japan to this day. Moreover, proliferation in arts gave birth to many cultural treasures, such as the tea ceremony, which gradually became a byword for refinement in the Edo period. Schools for tea ceremony then acted as another important source for promoting social etiquette to the commoners in Japan, such as zarei (bowing while kneeling).
In the business world
Customs and manners in Japanese business are reputed to be some of the most complicated and daunting in the world, especially to a foreign person who is not familiar with the Japanese ideology of ranks and traditions. Failure to perform the right type of ojigi for the other person's status is considered a workplace faux pas or even an offense. Especially more traditional and conservative Japanese people view ojigi as a representation of the Japanese identity and find beauty in the performance of a perfect ojigi with the correct posture. Therefore, many industries in Japan will offer new recruits extensive training on correct ways to perform ojigi and other important business etiquette.
Eshaku, keirei and saikeirei are the three typical categories of ojigi practiced in the business world in Japan. No matter which type is chosen, it is important to pay constant attention to one's muscles and posture. In particular, one's back should be kept straight and the body below the waist should stay still and vertical throughout the bowing gesture. Slouching backs and protruding hips are both considered ugly and unprofessional behaviors. Another important technique for ojigi is the synchronization of one's movements with one's breathing, commonly referred to as in Japanese. To elaborate, the lowering movement of one's upper body should take as long as the inhalation of one's natural breath. Next, one should stay completely still at the bowing position when exhaling, before returning to one's original stance during the inhalation of the second breath. Rei-sansoku ensures the harmonic balance between one's movements so that the ojigi feels neither rushed nor protracted.
Eshaku
is generally performed with a slight inclination of about 15° of one's upper torso. At the bowing position, one's eyes should glance at the floor roughly three meters in front of one's feet. It is a very casual form of greeting in business, usually performed between colleagues with the same status, or when more formal gestures are deemed unnecessary, like when one casually bumps into someone on the street.
Keirei
The second type, , is the most commonly used variation of ojigi in Japanese business. It gives a more formal and respectful impression than eshaku, but less than saikeirei, the final type of ojigi. Conventionally, keirei is performed with an inclination of about 30° of the upper body. At the bowing position, one's gaze should rest on the floor approximately 1 meter in front of his feet. Possible scenarios for its usage include greeting clients, entering a meeting and thanking superiors at work.
Saikeirei
Finally, , which literally means "the most respectful gesture", is, as the name suggests, the ojigi that shows the uttermost respect towards the other party. It is mostly used when greeting very important personnel, apologizing or asking for big favors. Saikeirei is characterized by an even deeper inclination of one's upper body than keirei, typically somewhere from 45° to 70°. Additionally, as saikeirei is used only in grave situations, one is expected to stay still at the bowing position for a relatively long time to show one's respect and sincerity.
In terms of hand positions, men should keep them naturally at both sides of their legs, whereas women often place one hand on top of the other in the center somewhere below their abdomen.
Zarei
Zarei is a bowing etiquette unique to East Asia, which involves bending one's upper body at kneeling, or seiza, position on traditional Japanese style tatami floors. With the Westernization of indoor decoration and lifestyles, zarei is becoming less and less commonly practiced in the daily lives of Japanese people. Some Japanese people even find zarei an excruciating ordeal to their knees and waists. Nevertheless, zarei remains an important part of Japanese culture, especially in more traditional activities such as the tea ceremony, kendo, and .
As with standing bows, zarei, as well as many other domains of Japanese culture like ikebana and garden design, can be classified into three main styles based on the doctrines of Japanese calligraphy: , the most formal style, the intermediate style, and , the most casual style.
Saikeirei (zarei version)
Saikeirei (the shin style) is the most formal and reverent of the three types. Starting from seiza position, the person is expected to lower his upper body all the way until his chest presses against his lap. In the process, his hands should slide forward along his thighs until they are on the floor roughly 7 cm away from his knees. In the final position, his face should be about 5 cm away from the floor. His palms should lie flat on the floor, forming a triangle directly under his face with the tips of the index fingers lightly touching one another. For saikeirei, like the standing version, it is important to allow an adequate amount of time in the bowing position before returning to the original seiza posture, in order to show the uttermost sincerity and respect. The entire procedure should take roughly 10 seconds to complete.
Futsūrei
is the most commonly used variation of zarei in formal situations and most traditional activities. To perform a futsūrei, one should lower one's upper body until one's face is roughly 30 cm away from the floor. In the meantime, one's hands should move in a similar fashion as saikeirei, again forming a triangle directly under one's face in the final bowing position.
Senrei
is the most casual type of zarei in everyday life, used mainly as greetings in informal situations. It is characterized by a relatively slight inclination (roughly 30°) of the upper torso. During the lowering movement, one's hands should slide naturally along one's thighs to the knees. In the bowing position, unlike the other two types, only one's fingertips should touch the floor. Men generally keep their hands in front of each knee, while women place their hands together in the center.
In various activities
Kendo
Kendo, like many other forms of martial arts in Japan, takes great pride in its samurai traditions. The kendo saying helps to illustrate the importance of civility and sportsmanship in its practice. Ojigi is especially an essential cog in its etiquette system, such that a kendo practitioner can bow as many as eighty times during a tournament or practice.
First of all, kendo practitioners bow to the dojo whenever they enter and leave the building, as it is considered a sacred space in martial arts practice. Upon arrival, the disciples will bow to their teachers and seniors as greetings, starting with the highest-ranking member. At the beginning and end of a match, opponents will bow to each other as a sign of mutual respect and humility. Before each training session, a player will bow first to the , then bow to his teachers and finally to his practice partner. In a tournament, the players of the first and last match usually bow to the referees before bowing to each other. Conventionally, a formal ojigi such as keirei or saikeirei is necessary when addressing people of higher positions, while a more casual bow of about 15° is typical between the opponents. When zarei is required, the players have to first . In kendo practice, it is customary for the players to kneel down by bending their left legs first and getting up with their right legs first, commonly known as in Japanese. It is said to serve the purpose from former times of making sure one can always draw the katana out as quickly as possible in case of emergencies, since the katana is usually carried on the left side of the body. For a similar reason, the right hand should lag slightly behind the left hand in reaching their final positions on the floor.
Shinto shrine visits
Like the religion itself, the etiquette of praying in Shintoism has gone through dramatic changes over the centuries. In modern-day Japan, worshipers at a Shinto shrine generally follow the so-called (二礼二拍手一礼).
First of all, upon arrival at the shrine, it is proper for worshipers to perform a slight eshaku towards the main temple building as they cross the torii, which is believed to be the sacred gateway between the mundane world and the realm of the gods. The same procedure applies when they are leaving the temple complex.
When they approach the main temple building, it is considered respectful to perform another eshaku towards the altar as an introduction. Next, most worshipers will throw some Japanese coins into the and ring the bell above the entrance for blessings. In the main praying process, worshipers should first perform two deep bows of up to 90° to pay tribute to the Shinto kami, followed by loudly clapping twice in front of the chest. Same as the noise made by the coins and the bell, the loud claps are believed to have the effect of exorcising negative energy or evil spirits. Finally, after making wishes to the kami with both palms held together in the clapping position, the worshiper should put the hands down and perform another deep bow to finish the praying ceremony.
Funerals
In a traditional Buddhist funeral in Japan, it is customary for the guests to mourn the deceased by , once during the and later again during the . Although different variations of the ritual exist, the version involving ritsurei (standing bows) is the most prevalent in modern society.
First of all, immediate relatives of the deceased will perform a formal bow to the Buddhist monks, who are hired to chant the religious sutra, and all the other guests to thank them for their attendance. Then, they will one by one walk up to the near the coffin to pay respect and bid farewell to the deceased. Ordinary guests will either follow them or, in other cases, line up to visit a separate incense burning station slightly further away. All mourners should perform a deep bow to the portrait of the deceased with their palms held together in the Buddhist fashion. Next, they should pinch some from the container with their right hands, raise it up to their foreheads and humbly drop it into the incense burners. Such process can be repeated up to three times depending on the religious customs of the region. Last but not least, it is also essential that the ordinary guests bow to the mourning family before and after the incense burning procedure to show their condolences.
The tea ceremony
The is a traditional art form in Japan featuring the ritualistic preparation and consumption of powdered green tea along with matching Japanese desserts. Every single element of the experience, from the calligraphy on the walls to the decorations of the utensils, is carefully tailored according to the aesthetic concepts of the host to match the season and theme of the gathering. Therefore, it is important for the guests to show their gratitude for the host's hard work by behaving in a humble and respectful manner.
When to bow
A regular tea ceremony usually consists of less than five guests, whose ranks, sitting positions and duties during the ceremony will be decided beforehand. A will be chosen, who will always be the first one served and engage in most of the ceremonial conversations with the .
Before going into the tea room, each guest should individually perform a formal bow to the space itself in respect to its profound spirituality. Upon entering, prior to the official start of the ceremony, the guests can take their time to admire the ornaments in the tokonoma and the utensils of the , which are all carefully selected to match the theme of the event. It is utterly important for the guests to show their appreciation of the host's effort by bowing to each piece of artwork before and after the admiration process. Then, formal bows will be performed by everyone in the room including the host to mark the beginning of the ceremony and later again at the start of the tea preparation procedure. When each course of dessert or tea is served, the host will bow to the guest of honor to indicate that it is ready for the guests to consume, and the guest of honor will bow in response as a form of gratitude. Moreover, it is customary for each guest to bow to the person behind as apology for consuming first. At the end of the ceremony, another round of bows will be exchanged between the guests and hosts to thank each other for the experience. The guest of honor will also bow to all the other guests to thank them for letting him sit in the most honorable position, while the other guests will return the bow to thank the guest of honor for the delivery of the interesting conversation with the host.
How to bow
Ojigi in Japanese tea ceremony is mainly done in the zarei fashion, which can be similarly classified into three types based on the degree of formality of the gesture: shin, gyō, and sō (). Although largely derivative from the samurai etiquette of the Edo period, contemporary zarei in tea ceremony is somewhat different from the aforementioned samurai version. In modern society, it is equally likely to see an ordinary Japanese person perform the zarei etiquette in either of these two variations.
The formal shin-style zarei is characterized by a 45° inclination of the upper body. In the bowing position, both hands should be fully rested on the floor in a triangle pattern with the tips of the index fingers touching each other. The semi-formal gyō-style zarei involves a 30° inclination of the upper body. Unlike the samurai version, just the parts of the fingers beyond the second knuckles should touch the floor in the bowing position. Finally, the casual sō-style zarei features a shallow 15° inclination of the upper body with only the fingertips contacting the floor. Details of the etiquette may vary depending on which school of tea ceremony one subscribes to, so it is always a good idea to check the manners of the host and the guest of honor for guidelines of proper decorum.
Additionally, in a tea ceremony, guests often bring with them a , which they will place horizontally on the floor in front of them before performing the formal and semi-formal zarei gestures.
See also
Etiquette in Japan
Prostration (Buddhism)
References
Bibliography
De Mente, B. L. (2017). Japan: A Guide to Traditions, Customs and Etiquette. Hong Kong: Tuttle Publishing. pp. 52–54, 65–69. .
Stalker, N. K. (2018). Japan: History of Culture from Classic to Cool. Oakland: University of California Press. pp. 79–179. LCCN 2017058048.
External links
Etiquette at Japan-Guide
Culture of Japan
Bowing
Gestures
Gestures of respect
fr:Politesse dans la culture japonaise#Les salutations | Bowing in Japan | [
"Biology"
] | 4,166 | [
"Behavior",
"Gestures",
"Human behavior"
] |
51,598,692 | https://en.wikipedia.org/wiki/Infantile%20apnea | Infantile apnea is a rare disease that is characterized by cessation of breathing in an infant for at least 20 seconds or a shorter respiratory pause that is associated with a slow heart rate, bluish discolouration of the skin, extreme paleness, gagging, choking and/or decreased muscle tone. Infantile apnea occurs in children under the age of one and it is more common in premature infants. Symptoms of infantile apnea occur most frequently during the rapid eye movement (REM) stage of sleep. The nature and severity of breathing problems in patients can be detected in a sleep study called a polysomnography which measures the brain waves, heartbeat, body movements and breathing of a patient overnight. Infantile apnea can be caused by developmental problems that result in an immature brainstem or it can be caused other medical conditions. As children grow and develop, infantile apnea usually does not persist. Infantile apnea may be related to some cases of sudden infant death syndrome (SIDS) however, the relationship between infantile apnea and SIDS is not known.
Cause
√ having a family history of sleep apnea.
√ being overweight or obese.
✓ having certain medical conditions (cerebral palsy, Down syndrome, sickle cell disease, abnormalities in the skull or face)
✓ being born with a low birth weight.
✓ having a large tongue.
Diagnosis
Classification
There are three major categories of apnea known as central, obstructive, and mixed apnea.
Central Apnea
Central apnea is characterized by insufficient responsiveness from respiratory centers such as the medulla, which results in poor coordination of the body systems that are necessary for breathing. Respiratory muscles and nerves to lose the ability to effectively receive and process signals from the brain causing respiratory efforts to cease. Central apnea is quite common and can be found in healthy, full-term infants for short periods of time before breathing patterns in the infant stabilize. In premature infants, central apnea is attributed to an underdeveloped respiratory system which results in decreased response to higher carbon dioxide levels and difficulty breathing. Head trauma may also cause central apnea as it interferes with normal signalling of the central respiratory system, this might be present in infants who suffer from abuse so investigating patient background is an important consideration.
Obstructive Apnea
Obstructive apnea occurs when the airway passages are obstructed and little to no air exchange occurs, resulting in impaired breathing. In some cases, it occurs when patients are born with a small airway opening. Patients with obstructive apnea often have vigorous inspiratory effort but the efforts are still ineffective. Normally, the muscles at the level of the throat relax and dilate while asleep in order to open up airway however, patients with obstructive apnea may have decreased neuromuscular tone of the muscles responsible for dilating the pharynx during sleep. The inability of the vocal cords to move and the presence of a foreign body may also cause obstructive apnea. Cases of obstructive apnea are rarely found in infants that are healthy.
Mixed Apnea
Mixed apnea is a combination of both central and obstructive factors. The majority of premature infants with sleep apnea have mixed apnea.
Epidemiology
When infants have a lower birth weight or younger gestational age, there is a greater risk of infantile apnea. With the advancement of neonatal intensive care units and the greater technology available, there are more successful premature births compared to the past. With the greater number of premature infants being born, there is also a greater number of children with infantile apnea. Approximately 85 percent of infants born with a weight less than experience infantile apnea within the first month after birth. This risk decreases to 25 percent for infants weighing less than . Studies have found that almost 2% of the pediatric population experience obstructive sleep apnea.
References
Breathing abnormalities
Sleep disorders
Pediatrics | Infantile apnea | [
"Biology"
] | 813 | [
"Behavior",
"Sleep",
"Sleep disorders"
] |
51,599,932 | https://en.wikipedia.org/wiki/Norclostebol%20acetate | Norclostebol acetate (brand name Anabol 4-19), or norchlorotestosterone acetate (NClTA), also known as 4-chloro-19-nortestosterone 17β-acetate or as 4-chloroestr-4-en-17β-ol-3-one, is a synthetic, injectable anabolic-androgenic steroid (AAS) and derivative of 19-nortestosterone (nandrolone). It is an androgen ester – specifically, the C17β acetate ester of norclostebol (4-chloro-19-nortestosterone).
See also
Clostebol
Clostebol acetate
Clostebol caproate
Clostebol propionate
Oxabolone
Oxabolone cipionate
References
Acetate esters
Androgen esters
Anabolic–androgenic steroids
Estranes
Organochlorides
Prodrugs | Norclostebol acetate | [
"Chemistry"
] | 214 | [
"Chemicals in medicine",
"Prodrugs"
] |
51,600,173 | https://en.wikipedia.org/wiki/Ofeq-11 | Ofeq-11, also known as Ofek 11 (Horizon in Hebrew), is part of the Ofeq family of reconnaissance satellites designed and built by Israel Aerospace Industries (IAI) for the Israeli Ministry of Defense.
Launch
Ofek-11 was launched on 13 September 2016, at 14:38 UTC from the Palmachim Airbase in Israel, two years after the launch of Ofeq-10. It was delivered using IAI's Shavit 2 launcher. Compared to its predecessor, the new satellite features an improved version of El-Op's "Jupiter High-Resolution Imaging System", with resolution increased to 0.5 meter, and uses a new satellite bus - OPSAT-3000 - which is a derivative of the satellite bus used in TecSAR-1.
Mission
According to reports, the launch initially looked like a success, but about 90 minutes later, engineers realized that while the satellite had entered orbit, not all systems were functioning or responding to instructions. However, after several days of remote repairs, the satellite was operational and taking high-quality pictures. It has been reported that South Korea is considering utilizing the satellite to obtain reconnaissance on North Korean activities.
References
Reconnaissance satellites of Israel
2016 in Israel
Israel Aerospace Industries satellites
Spacecraft launched in 2016
Spacecraft launched by Shavit rockets | Ofeq-11 | [
"Astronomy"
] | 268 | [
"Astronomy stubs",
"Spacecraft stubs"
] |
51,600,966 | https://en.wikipedia.org/wiki/Dynamical%20energy%20analysis | Dynamical energy analysis (DEA) is a method for numerically modelling structure borne sound and vibration in complex structures. It is applicable in the mid-to-high frequency range and is in this regime computational more efficient than traditional deterministic approaches (such as finite element and boundary element methods). In comparison to conventional statistical approaches such as statistical energy analysis (SEA), DEA provides more structural details and is less problematic with respect to subsystem division. The DEA method predicts the flow of vibrational wave energy across complex structures in terms of (linear) transport equations. These equations are then discretized and solved on meshes.
Key point summary of DEA
High frequency method in numerical acoustics.
The flow of energy is tracked across a mesh. Can be thought of as ray tracing using density of rays instead of individual rays.
Can use existing FEM meshes. No remodelling necessary.
Computational time is independent of frequency.
The necessary mesh resolution does not depend on frequency and can be chosen coarser than in FEM. It only should resolve the geometry.
Fine structural details can be resolved, in contrast to SEA which gives only one number per subsystem.
Greater flexibility for the models usable by DEA. No implicit assumptions (equilibrium in weakly coupled subsystems) as in SEA.
Introduction
Simulations of the vibro-acoustic properties of complex structures (such as cars, ships, airplanes,...) are routinely carried out in various design stages. For low frequencies, the established method of choice is the finite element method (FEM). But high frequency analysis using FEM requires very fine meshes of the body structure to capture the shorter wavelengths and therefore is computational extremely costly. Furthermore the structural response at high frequencies is very sensitive to small variations in material properties, geometry and boundary conditions. This makes the output of a single FEM calculation less reliable and makes ensemble averages necessary furthermore enhancing computational cost. Therefore at high frequencies other numerical methods with better computational efficiency are preferable.
The statistical energy analysis (SEA) has been developed to deal with high frequency problems and leads to relatively small and simple models. However, SEA is based on a set of often hard to verify assumptions, which effectively require diffuse wave fields and quasi-equilibrium of wave energy within weakly coupled (and weakly damped) sub-systems.
One alternative to SEA is to instead consider the original vibrational wave problem in the high frequency limit, leading to a ray tracing model of the structural vibrations. The tracking of individual rays across multiple reflection is not computational feasible because of the proliferation of trajectories. Instead, a better approach is tracking densities of rays propagated by a transfer operator. This forms the basis of the Dynamical Energy Analysis (DEA) method introduced in reference. DEA can be seen as an improvement over SEA where one lifts the diffusive field and the well separated subsystem assumption. One uses an energy density which depends both on position and momentum. DEA can work with relatively fine meshes where energy can flow freely between neighboring mesh cells. This allows far greater flexibility for the models used by DEA in comparison to the restriction imposed by SEA. No remodeling as for SEA is necessary as DEA can use meshes created for a FE analysis. As a result, finer structural details than SEA can be resolved by DEA.
Method
The implementation of DEA on meshes is called Discrete Flow Mapping (DFM). We will here briefly describe the idea behind DFM, for details see the references below. Using DFM it is possible to compute vibro-acoustic energy densities in complex structures at high frequencies, including multi-modal propagation and curved surfaces. DFM is a mesh based technique where a transfer operator is used to describe the flow of energy through boundaries of subsystems of the structure; the energy flow is represented in terms of a density of rays , that is, the energy flux through a given surface is given through the density of rays passing through the surface at point with direction . Here, parametrises the surface and is the direction component tangential to the surface. In what follows, the surfaces is represented by the union of all boundaries of the mesh cells of the FE mesh describing the car floor. The density , with phase space coordinate , is transported from one boundary to the adjacent boundary intersection via the boundary integral operator
where is the map determining where a ray starting on a boundary segment at point with direction passes through another boundary segment, and is a factor containing damping and reflection/transmission coefficients (akin to the coupling loss factors in SEA). It also governs the mode conversion probabilities in the case of both in-plane and flexural waves, which are derived from wave scattering theory. This allows DEA to take curvature and varying material parameters into account. Equation () is a way to write ray tracing across one single mesh cell in terms of an integral equation transferring an energy density from one surface to an adjacent surface.
In a next step, the transfer operator () is discretised using a set of basis functions of the phase space. Once the matrix has been constructed, the final energy density on the boundary phase-space of each element is given in terms of the initial density by the solution of a linear system of the form
The initial density models some source distribution for vibrational excitations, for example the engine in ship. Once the final density (describing the energy density
on all cell boundaries) has been computed, the energy density at any location inside the structure may be computed as a post-processing step.
Concerning the terminology, there is some ambiguity concerning the terms "Discrete Flow Mapping(DFM)" and "Dynamical Energy Analysis". To some extent, one can use one term in place of the other. For example, consider a plate. In DFM, one would subdivide the plate into many small triangles and propagate the flow of energy from triangle to (neighbouring) triangle. In DEA, one would not subdivide the plate, but use some high order basis functions (both in position and momentum) on the boundary of the plate. But in principle it would be admissible to describe both procedures as either DFM or DEA.
Examples
As an example application, a simulation of a car floor panel is shown here. A point excitation at 2500 Hz with 0.04 hysteretic damping was applied. The results from a frequency averaged FEM simulation are compared with a DEA simulation (for DEA, no frequency averaging is necessary). The results also show a good quantitative agreement. In particular, we see the directional dependence of the energy flow, which is predominantly in the horizontal direction as plotted. This is caused by several horizontally extended out-of-plane bulges. It is only in the lower right part of the panel, with negligible energy content, that deviations between the FEM and DFM predictions are visible. The total kinetic energy given by the DFM prediction is within 12% of the FEM prediction.
As a more applied example, the result of a DEA simulation on a Yanmar tractor model (body in blue: chassis/cabin steel frame and windows) is shown here to the left. The numerical DEA results are compared with experimental measurements at frequencies between 400 Hz and 4000 Hz for an excitation on the back of the gear casing. Both results agree favorably. The DEA simulation can be extended to predict the sound pressure level at driver's ear.
Notes
References
External links
University of Nottingham Wave Modelling Research Group . One of the foci of this research group is on DEA.
Mechanical vibrations
Acoustics | Dynamical energy analysis | [
"Physics",
"Engineering"
] | 1,547 | [
"Structural engineering",
"Classical mechanics",
"Acoustics",
"Mechanics",
"Mechanical vibrations"
] |
51,601,254 | https://en.wikipedia.org/wiki/Clomestrone | Clomestrone (brand names Arterolo, Atheran, Colesterel, Iposclerone, Liprotene, Persclerol, others; former developmental code name SC-8246), also known as 16α-chloroestrone 3-methyl ether, is a synthetic, steroidal, weak estrogen derived from estrone and used as an anticholesterolemic agent in the treatment of atherosclerosis. It is said to have beneficial effects on serum lipid profiles while producing minimal feminization, though some estrogenic side effects, including breast tenderness, loss of libido, and fatigue or avolition, were observed in most patients in clinical studies. The drug is a close analogue of mytatrienediol, and the two estrogens have similar drug profiles. Clomestrone was described in the literature in 1958 and introduced for medical use shortly thereafter.
See also
List of estrogens § Ethers of steroidal estrogens
Triparanol
References
Abandoned drugs
Estranes
Estrogen ethers
Hypolipidemic agents
Ketones
Organochlorides
Synthetic estrogens | Clomestrone | [
"Chemistry"
] | 242 | [
"Ketones",
"Functional groups",
"Drug safety",
"Abandoned drugs"
] |
51,601,592 | https://en.wikipedia.org/wiki/Floral%20scent | Floral scent, or flower scent, is composed of all the volatile organic compounds (VOCs), or aroma compounds, emitted by floral tissue (e.g. flower petals). Other names for floral scent include, aroma, fragrance, floral odour or perfume. Flower scent of most flowering plant species encompasses a diversity of VOCs, sometimes up to several hundred different compounds. The primary functions of floral scent are to deter herbivores and especially folivorous insects (see Plant defense against herbivory), and to attract pollinators. Floral scent is one of the most important communication channels mediating plant-pollinator interactions, along with visual cues (flower color, shape, etc.).
Biotic interactions
Perception by flower visitors
Flower visitors such as insects and bats detect floral scents thanks to chemoreceptors of variable specificity to a specific VOC. The fixation of a VOC on a chemoreceptor triggers the activation of an antennal glomerulus, further projecting on an olfactory receptor neuron and finally triggering a behavioral response after processing the information (see also Olfaction, Insect olfaction). The simultaneous perception of various VOCs may cause the activation of several glomeruli, but the output signal may not be additive due to synergistic or antagonistic mechanisms linked with inter-neuronal activity. Therefore, the perception of a VOC within a floral blend may trigger a different behavioral response than when perceived isolated. Similarly, the output signal is not proportional to the amount of VOCs, with some VOCs in low amounts in the floral blend having major effects on pollinator behavior. A good characterization of floral scent, both qualitative and quantitative, is necessary to understand and potentially predict flower visitors' behavior.
Flower visitors use floral scents to detect, recognize and locate their host species and even discriminate among flowers of the same plant. This is made possible by the high specificity of floral scent, where both diversity of VOCs and their relative amount may characterize the flowering species, an individual plant, a flower of the plant, and the distance of the plume from the source.
To make the best use of this specific information, flower visitors rely on long-term and short-term memory that allows them to efficiently choose their flowers. They learn to associate the floral scent of a plant with a reward such as nectar and pollen, and have different behavioral responses to known scents versus unknown ones. They are also able to react similarly to slightly different odor blends.
Mediated biotic interactions
A primary function of floral scent is to attract pollinators and ensure the reproduction of animal-pollinated plants.
Some families of VOCs presented in floral scents have likely evolved as herbivore repellents. However, these plant defenses are also used by herbivores themselves to locate a plant resource, similar to pollinators attracted by the floral scent. Therefore, flower traits can be subject to antagonistic selection pressures (positive selection by pollinators and negative selection by herbivores).
Plant-plant communications
Plants have an array of volatile compounds they can release to signal other plants. By unleashing these cues, plants learn more about their environment and sufficiently respond. However, there are still many factors about plant scents scientists are still trying to understand. Scientists have studied how many of the volatile compounds released by plants are from a floral source. A study concluded that floral cues are as important as other volatile compounds and are pertinent for plant-to-plant communication. Further research found that plants which receive the floral volatiles have higher fitness than other volatile cues because floral cues are the only compounds released by plants that indicate their kind of mating environment. Plants are able to respond to these mating cues and change adjustable floral phenotypes that can affect plant pollination and mating. Floral volatiles can ward off or attract pollinators/mates all at once. Depending on the number of floral signals released by a plant can control the level of attracting/repelling the plant wants. The composition of floral compounds and the rate of their release are the potential factors that control attraction/repellence. These two elements can be in response to ecological cues like high plant density and temperature. For instance, in sexually deceptive orchids, floral scents emitted after pollination reduce the flower's attractiveness to pollinators. This mechanism acts as a signal to pollinators to visit unpollinated flowers.
Environmental conditions can affect plant communication and signaling. Signal factors include temperature and plant density. Environmentally high temperatures increase the rate of releasing floral compounds, which can increase the amount of signal released and thus its ability to reach more plants. When plant density increases, plant communication increases as well, since plants would be near each other and have signals reach many neighboring plants. This can also increase the signal's reliability and lowering the chance the signal will degrade before it can reach other plants.
Biosynthesis of floral VOCs
Most floral VOCs belong to three main chemical classes. VOCs in the same chemical class are synthesized from a shared precursor, but the biochemical pathway is specific for each VOC and often varies from one plant species to another.
Terpenoids (or isoprenoids) are derived from isoprene and synthesized via the mevalonate pathway or the erythritol phosphate pathway. They represent the majority of floral VOCs and are often the most abundant compounds in floral scent blends.
The second chemical class is composed of the fatty acid derivatives synthesized from acetyl-CoA, most of which are known as green leaf volatiles, because they are also emitted by vegetative parts (i.e.: leaves and stems) of plants, and sometimes higher in abundance than from floral tissue.
The third chemical class is composed of benzenoids/phenylpropanoids, also known as aromatic compounds; they are synthesized from phenylalanine.
Regulation of emissions
Floral scent emissions of most flowering plants vary predictably throughout the day, following a circadian rhythm. This variation is controlled by light intensity. Maximal emissions coincide with peaks of the highest activity of visiting pollinators. For instance, snapdragon flowers, mostly pollinated by bees, have the highest emissions at noon, whereas nocturnally-visited tobacco plants have the highest emissions at night.
Floral scent emissions also vary along with floral development, with the highest emissions at anthesis, i.e. when the flower is fecund (highly fertile), and reduced emissions after pollination, probably due to mechanisms linked with fecundation. In tropical orchids, floral scent emission is terminated immediately following pollination, reducing the expenditure of energy on fragrance production. In petunia flowers, ethylene is released to stop the synthesis of benzenoid floral volatiles after successful pollination.
Abiotic factors, such as temperature, atmospheric concentration, hydric stress, and soil nutrient status also impact the regulation of floral scent. For instance, increased temperatures in the environment can increase the emission of VOCs in flowers, potentially altering communication between plants and pollinators.
Finally, biotic interactions may also affect the floral scent. Plant leaves attacked by herbivores emit new VOCs in response to the attack, the so-called herbivore-induced plant volatiles (HIPVs). Similarly, damaged flowers have a modified floral scent compared to undamaged ones. Micro-organisms present in nectar may alter floral scent emissions as well.
Measurement
Measuring floral scent both qualitatively (identification of VOCs) and quantitatively (absolute and/or relative emission of VOCs) requires the use of analytical chemistry techniques. It requires collecting floral VOCs, and then analyzing them.
VOCs sampling
The most popular methods rely on adsorbing floral VOCs on an adsorbent material such as SPME fibers or cartridges by pumping air sampled around inflorescences through the adsorbent material.
It is also possible to extract chemicals stocked in petals by immersing them in a solvent and then analyze the liquid residue. This is more adapted to the study of heavier organic compounds, and/or VOCs that are stored in floral tissue before being emitted into air.
Sample analysis
Desorption
Thermal desorption: the adsorbent material is flash-heated so that all adsorbed VOCs are carried away from the adsorbent and injected into the separation system. This is how work injectors in gas chromatography machines, which literally volatilize introduced samples. For VOCs adsorbed on bigger amount of adsorbent material such as cartridges, thermal desorption may require the use of a specific machine, a thermal desorber, connected to the separation system.
Desorption by solvent: VOCs adsorbed on the adsorbent material are carried away by a small quantity of solvent which is volatilized and injected in the separation system. Most commonly used solvents are very volatile molecules, such as methanol, to avoid co-elution with slightly heavier VOCs
Separation
Gas chromatography (GC) is ideal to separate volatilized VOCs due to their low molecular weight. VOCs are carried by a gas vector (helium) through a chromatographic column (the solid phase) on which they have different affinities, which allows to separate them.
Liquid chromatography may be used for liquid extractions of floral tissue.
Detection and identification
Separation systems are coupled with a detector, that allows the detection and identification of VOCs based on their molecular weight and chemical properties. The most used system for the analysis of floral scent samples is GC-MS (gas chromatography coupled with mass spectrometry).
Quantification
Quantification of VOCs is based on the peak area measured on the chromatogram and compared to the peak area of a chemical standard:
Internal calibration: a known quantity of a specific chemical standard is injected together with the VOCs, the measured area on the chromatogram is proportional to the injected quantity. Because the chemical properties of VOCs alter their affinity to the solid phase (the chromatographic column) and subsequently the peak area on the chromatogram, it is best to use several standards that reflect the best chemical diversity of the floral scent sample. This method allows a more robust comparison among samples.
External calibration: calibration curves (quantity vs. peak area) are established independently by the injection of a range of quantities of chemical standard. This method is best when the relative and absolute amount of VOCs in floral scent samples varies from sample to sample and from VOC to VOC and when the chemical diversity of VOCs in the sample is high. However, it is more time-consuming and may be a source of errors (e.g. matrix effects due to solvent or very abundant VOCs compared to trace VOCs).
Specificity of floral scent analysis
Floral scent is often composed of hundreds of VOCs, in very variable proportions. The method used is a tradeoff between accurately detecting quantifying minor compounds and avoiding detector saturation by major compounds. For most analysis methods routinely used, the detection threshold of many VOCs is still higher than the perception threshold of insects, which reduces our capacity to understand plant-insect interactions mediated by floral scent.
Further, the chemical diversity in floral scent samples is challenging. The time of analysis is proportional to the range in molecular weight of VOCs present in the sample, hence a high diversity will increase analysis time. Floral scent may also be composed of very similar molecules, such as isomers and especially enantiomers, which tend to co-elute and then to be very hardly separated. Unambiguously detecting and quantifying them is of importance though, as enantiomers may trigger very different responses in pollinators.
References
Chemical ecology
Flowers
Pollination | Floral scent | [
"Chemistry",
"Biology"
] | 2,440 | [
"Biochemistry",
"Chemical ecology"
] |
51,602,751 | https://en.wikipedia.org/wiki/Escovopsis%20aspergilloides | Escovopsis aspergilloides is a species of fungus that was rediscovered in 1995 by mycologists Keith A. Seifert, Robert A. Samson and Ignacio Chapela. Escovopsis aspergilloides co-exist in a symbiotic relationship with attini ants - fungus-growing ants. The highly evolved, ancient ant-fungus mutualism has become a model system in the study of symbiosis. In spite of this, the genus Escovopsis was not proposed until 1990 and the first two species were not formally described until the 1990s: E. weberi by Muchovej and Della Lucia in 1990 E. aspergilloides by Seifert, Samson and Chapela in 1995.
Discovery
E. aspergilloides was first discovered in 1893 by Alfred Moeller (Möller) in Blumenau on the island of Santa Catharina, Brazil - home of the German expatriate and naturalist, Fritz Müller - whose biography Moeller wrote. Alfred Moeller was undertaking a detailed study of local fungi for the Berlin Academy. His two-year field work in 1890 and 1891 resulted in his elaborate publication about attine ants and fungus entitled "The mushroom garden of some South American ants" about several fungus species in ant gardens.
Ant-fungus mutualism
There are 257 species of ants that constitute the tribe Attini. These leaf-cutting ants and fungus survive in an ant–fungus mutualism - an obligate symbiosis - in which neither can exist without the other. Ants grow the fungus - the basidiomycete cultivar - propagating it, nurturing and defending it - the fungus becomes almost their sole source of food.
Rediscovery and taxonomy
In 1995 Seifert, Samson and Chapela isolated Escovopsis aspergilloides from nests of the Trachymyrmex ruthae - an ant species originally from Trinidad. E. aspergilloides differs from other species in Escovopsis weberi by its "globose vesicles and narrow, ellipsoidal conidia."
American entomologist and myrmecologist Neal A. Weber began publishing his research on ants in 1934 continued to investigate the relationship between ants and fungus gardens for 35 years. Little had been published in the twentieth century about the species Escovopsis and ant gardens prior to his 1966 article "Fungus-growing ants" in the journal Science. Weber pioneered culture methods needed to distinguish the different species of fungus harboured by ants. In 1972 H. Z. Kreisel recognized one of Moeller's unnamed anamorphic fungi in his own research on the leaf-cutting ant Atta insularis and described it as a new genus and species – Phialocladus zsoltii but did not formally describe the genus and the species. In 1990 Muchovej and Della Lucia rediscovered the same fungus and – noting Kreisel's omission – renamed the genus Escovopsis and the species E. weberi in honour of Weber's work.
Three more species of Escovopsis were isolated from ant nests in Brazil by 2015, including Escovopsis moelleri, Escovopsis microspora and Escovopsis lentecrescens.
See also
Aspergillosis
References
Fungi described in 1995
Enigmatic Hypocreales taxa
Fungus species | Escovopsis aspergilloides | [
"Biology"
] | 700 | [
"Fungi",
"Fungus species"
] |
51,603,270 | https://en.wikipedia.org/wiki/Scoot-Mobile | The Scoot-Mobile prototype was built mostly from aircraft parts, manufactured by the Norman Anderson Co in Corunna, Michigan in 1946. The Scoot-Mobile was a 3-wheeler with automatic gear change, 3 wheel brakes, and could reach a top speed of 40 mph.
References
Defunct motor vehicle manufacturers of the United States
Motor vehicle manufacturers based in Michigan
Defunct manufacturing companies based in Michigan | Scoot-Mobile | [
"Physics"
] | 80 | [
"Physical systems",
"Transport",
"Transport stubs"
] |
51,606,548 | https://en.wikipedia.org/wiki/NGC%20212 | NGC 212 is a lenticular galaxy located approximately 369 million light-years from the Solar System in the constellation Phoenix. It was discovered on October 28, 1834 by John Herschel.
See also
Lenticular galaxy
List of NGC objects (1–1000)
Phoenix (constellation)
References
External links
SEDS
0212
2417
Lenticular galaxies
Phoenix (constellation) | NGC 212 | [
"Astronomy"
] | 73 | [
"Phoenix (constellation)",
"Constellations"
] |
51,606,849 | https://en.wikipedia.org/wiki/NGC%20213 | NGC 213 is a barred spiral galaxy located in the constellation Pisces. It was discovered on October 14, 1784, by William Herschel.
According to the SIMBAD database, NGC 213 is an Active Galaxy Nucleus Candidate, i.e. it has a compact region at the center of a galaxy that emits a significant amount of energy across the electromagnetic spectrum, with characteristics indicating that this luminosity is not produced by the stars.
One supernova has been observed in NGC 213: SN2020bqm (typeIa, mag. 18.4).
See also
List of NGC objects (1–1000)
References
0213
00436
Barred spiral galaxies
Pisces (constellation)
002469
17841114
Discoveries by William Herschel
+03-02-023
F00384+1611 | NGC 213 | [
"Astronomy"
] | 169 | [
"Pisces (constellation)",
"Constellations"
] |
51,609,856 | https://en.wikipedia.org/wiki/Mass-assignment%20protection | In the computing world, where software frameworks make life of developer easier, there are problems associated with it which the developer does not intend. Software frameworks use object-relational mapping (ORM) tool or active record pattern for converting data of different types and if the software framework does not have a strong mechanism to protect the fields of a class (the types of data), then it becomes easily exploitable by the attackers. These frameworks allow developers to bind parameters with HTTP and manipulate the data externally. The HTTP request that is generated carries the parameters that is used to create or manipulate objects in the application program.
The phrase mass assignment or overposting refers to assigning values to multiple attributes in a single go. It is a feature available in frameworks like Ruby on Rails that allows the modifications of multiple object attributes at once using modified URL. For example, @person = Person.new(params[:person]) #params contains multiple fields like name, email, isAdmin and contactThis Mass Assignment saves substantial amount of work for developers as they need not set each value individually.
Threats
In Mass Assignment, a malicious agent can attack and manipulate the data in various ways. It can send the tags which can make him assign various permissions which would otherwise be forbidden. For example, a database schema has a table "users" having field "admin" which specifies if corresponding user is admin or not. Malicious agent can easily send the value for this field to the server through HTTP request and mark himself as an admin. This is called Mass assignment vulnerability. It explores the security breaches that can be done using mass assignment.
GitHub got hacked in 2012 by exploiting mass assignment feature. Homakov who attacked the GitHub gained private access to Rails by replacing his SSH with SSH key of one of the members of Rails GitHub.
Protection
ASP.NET Core
In ASP.NET Core use the Bind attribute.
[HttpPost]
public IActionResult OnPost(
[Bind("LastName,FirstMidName,HireDate")] Instructor instructor)
Ruby
We can perform some changes in the active record models to ensure the protection of our data.
To use attr_protected: We specify the attributes which need to be protected. If the user tries mass assignment, then the user will get an error page which says Mass Assignment Security error and the attribute value will not be changed. This is also called blacklisting In this method, sometimes keeping track of all the attributes we want to protect is difficult. For example, in the code below, assign_project attribute is protected.Class Person < ActiveRecord::Base
has_many :projects
attr_protected :assign_project
endThis method optionally takes a role option using :as which enables to define multiple mass-assignment groupings. These attributes will have the :default role in case no role role is assigned. Here is an example which illustrates that assign_project will only be visible to admin. attr_protected :assign_project, :as => :admin
To use attr_accessible: We add attributes that are accessible to everyone and need not be protected. This is easier to manage as the attributes that can be mass-assigned can be explicitly selected. All others are considered as protected. This is sometimes referred to as whitelisting. attr_accessible :name, :email, :contact
To use Sanitize method: Another configuration which we can do to avoid mass assignment problems is called mass assignment sanitizer. This is a method called sanitize. This method filters the incoming requests and takes care that there should be no malicious tags. It only allows those tags that are whitelisted by the user. If the config config.active_record.mass_assignment_sanitizer is set to strict, it will raise ActiveModel::MassAssignmentSecurity::Error when mass assignment is not as intended.
To use Require and Permit: These methods are used in Rails 4. These provide functionalities that check the incoming requests and parameters. Require method checks whether all the required parameters are present. If not, it throws error. Permit method checks whether a particular parameter is permitted to be passed in mass assignment. It returns the list of the permitted parameters. This is also referred to as strong parameters.
Sometimes developer might forget adding attributes as accessible. So as to avoid this, recent versions of Rail has config setting config.active_record.whitelist_attributes = true" which creates blank white list of attributes and protects from Mass Assignment Vulnerability. Models still need to explicitly whitelist or blacklist accessible parameters.
References
Software development | Mass-assignment protection | [
"Technology",
"Engineering"
] | 971 | [
"Software engineering",
"Computer occupations",
"Software development"
] |
57,763,250 | https://en.wikipedia.org/wiki/Uncobasidium%20luteolum | Uncobasidium luteolum is a species of crust fungus in the family Meruliaceae, and the type species of genus Uncobasidium. The holotype was collected in Øvre Dividal National Park, in Målselv Municipality (Norway), where it was growing on Salix. The fungus has a monomitic hyphal system, with individual hyphae measuring 2.5–4 μm and having a clamp connection and oily refractive contents. The basidia are four-sterigmate, measure 30–50 by 8 μm, and feature a hook-shaped protuberance. Its spores are ellipsoid to obovate in shape, measuring 9 by 6 μm. Uncobasidium roseocremeum, found in South America, differs microscopically from U. luteolum in its larger, spherical spores, and the presence of encrusted hyphidia.
References
Meruliaceae
Fungi described in 1978
Fungi of Europe
Taxa named by Leif Ryvarden
Fungus species | Uncobasidium luteolum | [
"Biology"
] | 221 | [
"Fungi",
"Fungus species"
] |
57,763,698 | https://en.wikipedia.org/wiki/EC508 | EC508, also known as estradiol 17β-(1-(4-(aminosulfonyl)benzoyl)--proline), is an estrogen which is under development by Evestra for use in menopausal hormone therapy and as a hormonal contraceptive for the prevention of pregnancy in women. It is an orally active estrogen ester – specifically, a C17β sulfonamide–proline ester of the natural and bioidentical estrogen estradiol – and acts as a prodrug of estradiol in the body. However, unlike oral estradiol and conventional oral estradiol esters such as estradiol valerate, EC508 undergoes little or no first-pass metabolism, has high oral bioavailability, and does not have disproportionate estrogenic effects in the liver. As such, it has a variety of desirable advantages over oral estradiol, similarly to parenteral estradiol, but with the convenience of oral administration. EC508 is a candidate with the potential to replace not only oral estradiol in clinical practice, but also ethinylestradiol in oral contraceptives. Evestra intends to seek Investigational New Drug status for EC508 in the second quarter of 2018.
Pharmacokinetics
Relative to parenteral routes of estradiol like vaginal, transdermal, and injection, oral estradiol is characterized by low bioavailability and disproportionate effects on liver protein synthesis. Due to extensive metabolism during the first-pass into estrone and estrogen conjugates like estrone sulfate, the oral bioavailability of estradiol and conventional estradiol esters like estradiol valerate is only about 5%, and there is high interindividual variability in estradiol levels achieved. Moreover, because of the first-pass, estradiol levels in the liver are 4 or 5 times higher with oral estradiol than those in the circulation. As a result, oral estradiol has disproportionate estrogenic effects on the hepatic production of lipids, hemostatic factors, growth hormone/insulin-like growth factor 1 axis proteins, angiotensinogen, and other proteins. This is unfavorable and may result in an increased risk of venous thromboembolism, cardiovascular events, and other adverse effects.
The pharmacokinetics of EC508 were assessed in rats; its bioavailability was found to be complete (100%), its clearance in blood was low, and its biological half-life was prolonged at about 5 hours. A single oral dose of 5.0 mg/kg EC508 in rats resulted in peak levels of estradiol of 6,104 ng/mL (6,104,000 pg/mL). EC508 itself showed poor activity as an agonist of the estrogen receptor, with an value of 432 nM relative to 2.3 nM for estradiol (a 188-fold difference), indicating that the estrogenic activity of the compound is solely due to hydrolysis into estradiol. EC508 showed very high oral estrogenic potency, around 100 times that of estradiol and 10 times that of ethinylestradiol in rats. This was determined by uterotrophic effect in ovariectomized rats; an oral dosage of 10 μg/day resulted in uterine weight doubling with EC508, while no effect was observed with estradiol and only a small effect on uterine weight was measured with ethinylestradiol. Conversely, across the dosages assessed, oral estradiol and ethinylestradiol showed marked effects on cholesterol and angiotensinogen levels, while oral EC508 and parenteral estradiol showed no effect at all on these hepatic proteins. These findings are in accordance with the notion that oral EC508, unlike oral estradiol and ethinylestradiol but similarly to parenteral estradiol, bypasses first-pass metabolism and the liver.
The absence of first-pass metabolism and lack of disproportionate liver exposure with EC508 is thought to be due to reversible binding of the sulfonamide moiety of EC508 to an enzyme called carbonic anhydrase II (CAII). EC508 shows moderate affinity for human CAII, with an for binding inhibition of 110 nM. CAII is highly concentrated in erythrocytes (red blood cells), which are present in large quantity in the blood of the hepatic portal vein. It is believed that following its absorption in the intestines and its entrance into the hepatic portal vein, EC508 is taken up by and massively accumulated in erythrocytes, which prevents it from entering the liver and results in it being transported by erythrocytes straight into the circulation. From circulating erythrocytes, EC508 is thought to be slowly released and then hydrolyzed into estradiol. However, one sulfonamide ester of estradiol related to EC508 known as EC518 showed similar properties with very low or absent binding to CAII and hence probably lacking erythrocyte binding, which raises questions about the necessity of CAII binding for such properties and the mechanism by which they occur.
History
Estradiol sulfamate (E2MATE) is a C3 sulfamate ester of estradiol which was developed in the 1990s and was a predecessor of EC508. It binds to CAII, is taken up into and stored within erythrocytes, and shows similar properties to EC508. As a result, E2MATE was under development for potential clinical use as an oral estrogen. However, it showed no increase in estradiol levels and no estrogenic effects in human clinical trials. It appears that there are species differences with E2MATE between rats and primates and that the lack of activity in humans is because E2MATE additionally acts as a highly potent inhibitor of steroid sulfatase. This enzyme is responsible for the hydrolysis of sulfur-based estradiol esters like E2MATE and EC508 into estradiol. By inhibiting steroid sulfatase, E2MATE prevents its own activation into estradiol, which effectively abolishes its estrogenic activity. In addition, it was found that E2MATE was substantially transformed into estrone sulfamate (EMATE) in erythrocytes, which may have further impeded its capacity to be activated into estradiol. In contrast to E2MATE, EC508 is not thought to be a steroid sulfatase inhibitor and cannot be transformed into the corresponding estrone equivalent.
A C17β sulfonamide–proline testosterone ester known as EC586, which has similar properties to those of EC508, is also under development by Evestra, specifically as an androgen and potent oral testosterone prodrug for use in androgen replacement therapy in men.
Clinical trials for EC586 and EC508 are undergoing as of 2023.
See also
List of estrogen esters § Estradiol esters
List of investigational sex-hormonal agents § Estrogenics
References
External links
R&D Research / Research Pipeline - Evestra, Inc.
Amino acids
Carboxylic acids
Diols
Estradiol esters
Estranes
Experimental sex-hormone agents
Pyrrolidines
Sulfonamides
Synthetic estrogens | EC508 | [
"Chemistry"
] | 1,596 | [
"Amino acids",
"Biomolecules by chemical classification",
"Carboxylic acids",
"Functional groups"
] |
57,763,866 | https://en.wikipedia.org/wiki/DriveOhio | DriveOhio is an initiative within the Ohio Department of Transportation that aims to organize and accelerate smart vehicle and connected vehicle projects in the state of Ohio. It offers to be the single point of contact for policy makers, agencies, researchers, and private companies to collaborate with one another on smart transportation efforts around the state.
Mission
DriveOhio's mission is to serve as Ohio's central hub for "smart mobility", which it defines as the use of technology to move people and goods from one place to another as effectively as possible. In principle this includes all modes of transportation, including autonomous vehicles, drones, and ride sharing services. However, the initial focus of DriveOhio is to enable cars to connect with and communicate with highway infrastructure, through a fiber optic road network. Specific mission items for the center are established in Ohio Executive Order 2018-01K, which refers to DriveOhio as "the statewide center for smart mobility":
Establish communication between the agencies building Ohio's infrastructure and the organizations which are developing mobility technology.
Serve as the point of contact for mobility technology organizations that want to innovate in Ohio.
Help Ohio's government to plan for the future of transportation technology. This includes the development of policies, goals, recommendations, and operating standards.
Help to locate financing for new technology.
Work with other state agencies to help Ohio workers transition toward future transportation jobs.
History
DriveOhio was formed through an executive order by Ohio Governor John Kasich on January 18, 2018. The desire to attract investments and jobs in Ohio was a motivator for creating the program. Jim Barna, formerly the Chief Engineer for ODOT, was made executive director of the new organization.
Besides establishing DriveOhio, the executive order also mandates that all state vehicles be equipped with on-board communication devices by 2023.
Less than a month after formation, on February 8, 2018, DriveOhio held its first Smart Mobility Summit as a public/private exchange of ideas.
On May 9, 2018, Executive Order 2018-04K was signed, which authorizes autonomous vehicles to begin testing in Ohio. Participating companies and municipalities are required to coordinate through DriveOhio.
On July 9, 2018, the Transportation Research Center, an automotive proving ground near East Liberty, broke ground on a new facility for testing autonomous and connected vehicles called the SMARTCenter. This center will offer a variety of test scenarios for evaluating autonomous vehicles, and will be equipped with the wireless sensors used by connected vehicles.
Structure
The executive director is appointed by and reports to the current Director of ODOT, and may staff the organization as necessary. There are also two all-volunteer boards, the DriveOhio Government Advisory Board and the DriveOhio Expert Advisory Board. The Government Board represents local government, and the Expert Board represents particular industries. The chairs of both boards are selected by the ODOT Director, and all other members are chosen by the Governor, with no set limit on the size of each board.
DriveOhio also absorbed ODOT's UAS Center division, formerly the Ohio/Indiana UAS Center. The DriveOhio UAS Center is headed by Director Fred Judson, and is headquartered at the Springfield–Beckley Municipal Airport in Springfield, Ohio. Its mission is to safely study and apply unmanned aerial systems (UAS) technology in the State of Ohio.
Projects
The agencies which participate in DriveOhio oversee a variety of transportation-related projects.
U.S. 33 Smart Mobility Corridor. A 35-mile section of U.S. 33 will be furnished with fiber-optic cable and dedicated short-range communication (DSRC) units, placed every 600 meters.
Connected Marysville. The City of Marysville and ODOT will be equipping some of their vehicles, along with the vehicles of volunteers, with onboard units to communicate with the highway DSRCs. Honda, which operates the Marysville Auto Plant, will also be providing onboard units for the vehicles of local employees. These joint efforts are expected to result in 10% of all Marysville traffic being able to actively communicate with the highway infrastructure. The vehicle data will initially be used in conjunction with smart traffic signals to try to improve traffic flow and safety. It is also claimed to eventually provide guidance to snow and ice cleanup crews.
I-670 SmartLane. A nine-mile section of I-670 will be turned into the state's first "smart lane", in which the highway shoulder can be enabled as an extra lane on demand. Construction began on June 27, 2018.
Smart Columbus. The City of Columbus received $50 million in grants to build a smart transportation system. The initiative has many ongoing projects and is seeking additional funding. The city offers a "Smart Columbus Experience Center" to the public.
Other projects
I-90 Lake Effect Corridor. A 60-mile section of Interstate 90, located in the far northeast "Snow Belt" corner of the state, will have DSRC units installed along its length. Wireless units will also be installed on public service vehicles to test the communication system. This area was chosen as a pilot because of its dangerous lake-effect snow conditions. I-90 is part of the "Smart Belt Coalition" between Ohio, Michigan, and Pennsylvania.
Ohio Turnpike. Similar to the I-90 project, the Ohio Turnpike will also receive DSRC units, along with units in a set of test vehicles.
Ground-Based Detect and Avoid Drone Pilot. The UAS Center is partnering with the Air Force Research Laboratory in a test program to fly UAS aircraft in the National Airspace System (NAS) beyond visual line of sight. This requires the development of an unmanned traffic management (UTM) system to track commercial flights, drones, and low-altitude passenger craft. Another facet of the project is provided air-based traffic monitoring on the 33 Smart Mobility Corridor.
Possible future projects include an I-75 smart corridor that extends up into Michigan.
References
Transportation in Ohio
Intelligent transportation systems
Traffic management
Unmanned ground vehicles | DriveOhio | [
"Technology",
"Engineering"
] | 1,214 | [
"Systems engineering",
"Transport systems",
"Traffic management",
"Information systems",
"Warning systems",
"Intelligent transportation systems"
] |
57,765,418 | https://en.wikipedia.org/wiki/EC586 | EC586, also known as testosterone 17β-(1-((5-(aminosulfonyl)-2-pyridinyl)carbonyl)--proline), is an androgen and anabolic steroid which is under development by Evestra for use in androgen replacement therapy in men. It is an orally active androgen ester – specifically, a C17β sulfonamide–proline ester of the natural and bioidentical androgen testosterone – and acts as a prodrug of testosterone in the body. However, unlike oral testosterone and conventional oral testosterone esters such as testosterone undecanoate, EC586 has high oral potency, may undergo little or no first-pass metabolism, and may not have disproportionate androgenic effects in the liver. As such, it may have a variety of desirable advantages over oral testosterone, similarly to parenteral testosterone, but with the convenience of oral administration. Evestra intends to seek Investigational New Drug status for EC586 in the fourth quarter of 2018.
The pharmacokinetics of oral EC586 have been briefly assessed in rats in a small pilot study. Oral EC586 showed area-under-the-curve (AUC) levels that were more than 100-fold greater than those of oral testosterone propionate, the C17β propionate ester of testosterone (AUC0-3h = 330 ng/mL and 2.5 ng/mL, respectively, for doses of 3.0 mg/rat each). As such, EC586 would appear to possess strongly increased oral bioavailability, potency, and systemic exposure relative to testosterone propionate. Additional research and details on the pharmacokinetics and properties of EC586 are to be published "soon".
The mechanism for the absence of first-pass metabolism and lack of disproportionate liver exposure with oral administration has been elucidated for a closely related sulfonamide–proline estradiol ester known as EC508, which shows the same properties as EC586.
Clinical trials for EC586 and EC508 are undergoing as of 2023.
See also
List of androgen esters § Testosterone esters
List of investigational sex-hormonal agents § Androgenics
References
External links
R&D Research / Research Pipeline - Evestra, Inc.
Amino acids
Anabolic–androgenic steroids
Androstanes
Experimental sex-hormone agents
Enones
Pyridines
Androgen esters
Sulfonamides
Testosterone
Testosterone esters | EC586 | [
"Chemistry"
] | 546 | [
"Amino acids",
"Biomolecules by chemical classification"
] |
57,766,017 | https://en.wikipedia.org/wiki/DTaP-IPV%20vaccine | DTaP-IPV vaccine is a combination vaccine whose full generic name is diphtheria and tetanus toxoids and acellular pertussis adsorbed and inactivated poliovirus vaccine (IPV).
It is also known as DTaP/IPV, dTaP/IPV, DTPa-IPV, or DPT-IPV. It protects against the infectious diseases diphtheria, tetanus, pertussis, and poliomyelitis.
Branded formulations marketed in the USA are Kinrix from GlaxoSmithKline and Quadracel from Sanofi Pasteur.
Repevax is available in the UK.
In Japan, the formulation is called 四種混合(shishukongou - "mixture of 4").
Astellas markets it under the クアトロバック ('Quattro-back') formulation, while another is available from Mitsubishi Tanabe Pharma named テトラビック ('Tetrabic').
A previous product by Takeda Pharmaceutical Company has been withdrawn by the company.
References
Combination vaccines
Diphtheria
Whooping cough
Tetanus
Polio
Vaccines | DTaP-IPV vaccine | [
"Biology"
] | 249 | [
"Vaccination",
"Vaccines"
] |
57,766,524 | https://en.wikipedia.org/wiki/DTaP-IPV/Hib%20vaccine | DTaP-IPV/Hib vaccine is a 5-in-1 combination vaccine that protects against diphtheria, tetanus, whooping cough, polio, and Haemophilus influenzae type B.
Its generic name is "diphtheria and tetanus toxoids and acellular pertussis adsorbed, inactivated poliovirus and haemophilus B conjugate vaccine", and it is also known as DTaP-IPV-Hib.
Uses
DTaP-IPV/Hib vaccine is administered to young children to immunise against diphtheria, tetanus, pertussis, poliomyelitis, and diseases caused by Haemophilus influenzae type B.
Formulations
A branded formulation marketed in the United States is Pentacel, manufactured by Sanofi Pasteur.
Pentacel is known in the UK and Canada as Pediacel.
An equivalent vaccine marketed in the UK and Canada by GlaxoSmithKline is Infanrix IPV + Hib. This is a two-part vaccine. The DTaP-IPV component is supplied as a sterile liquid, which is used to reconstitute lyophilized (freeze-dried) Hib vaccine.
Pentaxim is a liquid formulation marketed by Sanofi Pasteur.
Availability
It is only licensed for young children. The United States Food and Drug Administration has approved the vaccine for children from age 6 weeks up to age 5 years. It was used in the UK until 2017, following which a 6-in-1 vaccine became available containing the additional protection against Hepatitis B.
References
Combination vaccines
Diphtheria
Haemophilus
Whooping cough
Polio
Tetanus
Vaccines | DTaP-IPV/Hib vaccine | [
"Biology"
] | 367 | [
"Vaccination",
"Vaccines"
] |
57,766,600 | https://en.wikipedia.org/wiki/DTaP-IPV-HepB%20vaccine | DTaP-IPV-HepB vaccine is a combination vaccine whose generic name is diphtheria and tetanus toxoids and acellular pertussis adsorbed, hepatitis B (recombinant) and inactivated polio vaccine or DTaP-IPV-Hep B. It protects against the infectious diseases diphtheria, tetanus, pertussis, poliomyelitis, and hepatitis B.
A branded formulation is marketed in the U.S. as Pediarix by GlaxoSmithKline.
DTaP
The DTaP portion of the vaccine protects against three bacterial infections: diphtheria, tetanus, and pertussis (whooping cough). Diphtheria is a bacterium that causes problems with breathing, heart failure, paralysis, and in some cases death. It is spread via human to human interaction. Tetanus is spread via open cuts or wounds in the body. It can lead to stiffening of the muscles, which can result in difficulties breathing. Pertussis, also known as whooping cough, is the is "aP" portion of the DTaP vaccine. Like diphtheria, it is spread via human to human interaction. With the vaccine, children can build up a supply of antibodies that prevent infection. In general, the DTaP vaccine is only administered to children ages 7 and younger.
IPV
The IPV portion of the DTaP-IPV-HepB vaccine protects against poliomyelitis, otherwise known as polio. IPV stands for inactivated poliovirus vaccine, which means that it does not use a live strand of the polio virus and cannot result in polio. Polio is a life-threatening disease that can cause paralysis, poor muscle function that weakens the ability to breath, and brain problems. Since 2016, the United States requires all polio vaccines administered to be IPV and not OPV to eliminate the use of live polio virus.
HepB
The HepB portion of the vaccine protects against hepatitis B. Hepatitis B is a virus that can be spread via mother to child if the mother is infected with hepatitis B, so most doctors recommend that infants be vaccinated. In most individuals infected with hepatitis B, they are asymptomatic. However, symptoms of hepatitis B include flu-like symptoms, diarrhea, and jaundice. Hepatitis B can either be acute or chronic and can ultimately lead to damage of the liver.
Uses
The main reason for the use of combination vaccines is because they require fewer shots. Instead of having a child receive separate shots for each virus they need protection from, scientists were able to create vaccines, like MMR and DTap-IPV-HepB, that protect against several viruses at a time. Another reason is that with the IPV (inactivated poliovirus vaccine) portion of the DTap-IPV-HeB vaccine, children no longer have to take the oral vaccine (OPV) that was administered starting in the 1950s. Although the oral vaccine helped eliminate polio in several countries and is still used in countries today, OPV contains live polio virus and can still result in individuals getting polio. Combination vaccines are also more cost effective and make it more likely for children to receive vaccinations. With the DTaP vaccine on its own, it is to be administered in five doses. However, when the DTaP vaccine is administered through the DTaP-IPV-HepB combination vaccine like Pediarix, it only has to be administered in three doses.
Formulations
In general, the DTaP-IPV-HepB vaccine is recommended to be administered in three doses around 8, 12, and 16 weeks old. Talk to your doctor about the vaccine schedule that is best for your child. There are several common DTaP combinations vaccines: Pediarix, Kinrix, and Pentacel. Pediarix combines DTap-IPV-Hep B and Pentacel combines DTaP-IPV-Hib (Haemophilus influenza type b); however, Kinrix only combines DTaP-IPV, which leaves out Hep B and Hib. Therefore, Pediarix and Pentacel are more commonly used because they protect from five rather than four viruses in each dose. For protecting against DTaP viruses, polio, and hepatitis B, Pediarix is the recommended formulation.
Pediarix
Pediarix is vaccine that is protective against diphtheria, tetanus, pertussis, hepatitis B, and polio. This vaccine is FDA approved to be administered to infants in three doses between ages six weeks and six years. Pediarix should not be injected into any child seven years old or older. However, it is recommended that the immunizations be done at months two, four, and six. The wide age gap between six weeks and six years allows for children who fall behind in their vaccinations to still have the opportunity to be vaccinated. From the moment of birth, babies can become infected with these life-threatening diseases, which is why this vaccine is recommended to be given so early on. With these three doses, the Pediarix vaccine has been given to over 8,088 infants. Each does is 0.5mL and is given via intramuscular. For children ages one and younger, the vaccine is injected into the thigh. While for children older than one, it is injected into the deltoid muscle of the arm. Because the Pediarix vaccine has HepB, is it important to note the mother's HBsAg status. Pediarix is recommended for mothers who are HBsAg-negative; however, in 2003 it was approved that children whose mothers are HBsAg-positive can also receive the Pediarix immunization. Looking at overall completed vaccine records, Pediarix completes the amount of HepB doses that an individual needs to be protected. However, boosters are still needed for DTaP and IPV vaccines after the three doses of Pediarix.
DTaP-IPV-HepB virus activity
As of 2021, there were 1,609 cases of pertussis in the United States. The majority of cases were found amongst 6-11 month old children.
References
Combination vaccines
Drugs developed by GSK plc
Diphtheria
Hepatitis B
Whooping cough
Polio
Tetanus
Vaccines | DTaP-IPV-HepB vaccine | [
"Biology"
] | 1,327 | [
"Vaccination",
"Vaccines"
] |
57,766,861 | https://en.wikipedia.org/wiki/Progesterone%20carboxymethyloxime | Progesterone carboxymethyloxime, or progesterone 3-(O-carboxymethyl)oxime (P4-3-CMO), is a progestin which was never marketed. It is an oral prodrug of progesterone with improved pharmacokinetic properties. The compound was developed in an attempt to address the poor oral pharmacokinetics of progesterone, including its very low bioavailability and short biological half-life. These properties of progesterone are thought to be caused by its low water solubility and high metabolic clearance rate due to rapid degradation in the intestines and liver. Drugs with low aqueous solubility are not absorbed well in the intestines because their dissolution in water is limited.
P4-3-CMO (as the potassium salt) showed water solubility that was increased by more than four orders of magnitude relative to progesterone (solubility = 9.44 mol/L and 0.0006 mol/L, respectively). In addition, it showed an in vitro terminal half-life in rat liver microsomes that was 363-fold longer than that of progesterone (half-life = 795.5 minutes and 2.2 minutes, respectively). As such, P4-3-CMO could have both improved absorption and increased metabolic stability relative to progesterone. However, the compound has not been further assessed nor studied in humans.
See also
List of neurosteroids § Inhibitory > Synthetic > Pregnanes
List of progestogen esters § Oximes of progesterone derivatives
References
Abandoned drugs
Alkene derivatives
Diketones
Neurosteroids
Ketoximes
Pregnanes
Sex hormone esters and conjugates
Progestogens
Steroid oximes | Progesterone carboxymethyloxime | [
"Chemistry"
] | 398 | [
"Drug safety",
"Abandoned drugs"
] |
57,766,938 | https://en.wikipedia.org/wiki/DPT-Hib%20vaccine | DPT-Hib vaccine is a combination vaccine whose generic name is diphtheria and tetanus toxoids and whole-cell pertussis vaccine adsorbed with Hib conjugate vaccine, sometimes abbreviated to DPT-Hib. It protects against the infectious diseases diphtheria, tetanus, pertussis, and Haemophilus influenzae type B.
A branded formulation was marketed in the US as Tetramune by Lederle Praxis Biologicals (subsequently acquired by Wyeth). Tetramune has since been discontinued.
References
Vaccines
Combination vaccines
Diphtheria
Tetanus
Whooping cough
Haemophilus | DPT-Hib vaccine | [
"Biology"
] | 144 | [
"Vaccination",
"Vaccines"
] |
57,767,854 | https://en.wikipedia.org/wiki/AN/ALR-20 | AN/ALR-20(A) is an airborne wideband tuned radio frequency receiver providing a panoramic display of Radio Frequency (RF) spectrum on US Air Force B-52 Stratofortress aircraft. As a stand-alone system, it is used by the Electronics Warfare Officer (EWO) to evaluate and determine various classifications of threats to the aircraft, identifying various signals including search, acquisition, and tracking radars as well as communications. Because it allows a broad view of the RF spectrum, its situational awareness also provides for analysis of the efficacy of jamming techniques employed by the EWO using other systems. First manufactured in the late 1960s, the system is a passive Electronic Support Measures (ESM) tuned radio frequency receiver. It is the primary tool used by the EWO to evaluate threats.
History
First developed in the early 1960s, the ALR-20 began appearing on B-52D bombers (before 1967) and B-52Gs in 1967-1969. In accordance with the Joint Electronics Type Designation System (JETDS), the "AN/ALR-20" designation represents the 20th design of an Army-Navy electronic device for passive countermeasures signal receiver. The JETDS system also now is used to name Air Force systems.
The ALR-20 did not undergo any significant upgrades or design changes until the 1980s when solid-state components were added to the system's tuners upgrading older tube-based technology. At the beginning of the 1990s, the outdated panoramic display (using old cathode ray tube technology) needed replacement due to the existing display becoming unsupportable. Until the late 1990s, the ALR-20's panoramic receiver display utilized Cathode-Ray Tube (CRT) technology. This replacement was delivered in the late 1990s. At that time, tuners and the power supply were determined to also need replacement for the same reasons. Today, deployed on B-52H bombers, the system still provides the EWO a display of six different RF bands, allowing for detection and identification of threat signals.
Into the early 2000s, it was determined the system was "becoming unsupportable due to vanishing vendors and obsolete technology". Under the B-52 Situational Awareness Defensive Improvement (SADI) program, the ALR-20 is expected to be replaced with a defensive system upgrade. The upgrade is expected to create up to thirty-fold improvements in reliability. Efforts to replace the ALR-20 continued into the mid-2000s, while some work was done to continue maintaining line replaceable units (LRUs). In 1999, ninety-one LRU-1s, fifty-four LRU-3s, thirty-six LRU-8s, eighty-three LRU-9s were repaired at a total cost of over $315,000. According to the Air Force's Fiscal Year (FY) 2004/2005 budget estimates, SADI would cost just over $70.9 million.
Electronic Warfare Officers undergo extensive training concerning the ALR-20 panoramic system.
Technical description
Features
The ALR-20's panoramic display is the EWO's primary source for analysis of potential threats through a very wide part of the electromagnetic spectrum. The early cathode-ray tube for the display (seen in the image to the right) had an orange tint displaying six different horizontal lines that represented a part of the spectrum. The signals displayed on those lines may be quickly analyzed allowing the EWO to bring the proper countermeasures for multiple different threats at once.
Components
Receiving Set Controller - LRU-1
Panoramic Display
Power Supply - LRU-3
Radio Frequency Tuner - LRU-8
Radio Frequency Tuner - LRU-9
Variants
AN/ALR-20
AN/ALR-20A
See also
List of military electronics of the United States
References
External links
AF.mil - B-52H Stratofortress Fact Sheet
Electronic warfare equipment
Military electronics of the United States
Equipment of the United States Air Force
Electronic countermeasures
Electronic warfare
Military equipment introduced in the 1960s
Radar warning receivers
Radiofrequency receivers | AN/ALR-20 | [
"Technology"
] | 857 | [
"Warning systems",
"Radar warning receivers"
] |
57,769,133 | https://en.wikipedia.org/wiki/Close%20Coupled%20Cooling | Close Coupled Cooling is a last generation cooling system particularly used in data centers. The goal of close coupled cooling is to bring heat transfer closest to its source: the equipment rack. By moving the air conditioner closer to the equipment rack a more precise delivery of inlet air and a more immediate capture of exhaust air is ensured.
Air Conditioner Types
Commercially available close coupled solutions can be divided into two categories: Open-Loop and Closed-Loop.
Open-Loop Configuration
Open-Loop configurations are not totally independent from the room they are installed, and air flows interact with the ambient room environment.
In-Row Air Conditioners
Row-Based Air Conditioning units are installed inside the rack rows. Air flows generally follow short and linear paths, reducing, in this way, the necessary power needed to start up the fans and increasing the energy efficiency.
A Row-Based cooling solution offers one advantage with respect to the Room-Based solution, since the former one can be better adapted to the needs of cooling for specific rows; it is anyway appropriate not to locate the conditioning units at the beginning or at the end of the rows to maximise their performance.
Rear Door Heat Exchangers
This type of solution is based on the substitution of the rear door of an existing rack.
These heat exchangers leverage the front-to-back air dissipation of most of the IT equipments: the servers dissipate warm air, which passes the heat exchanger coil and is returned to the room at an agreeable temperature.
The cooling units of this category do not occupy additional space, so they are particularly indicated either to cool all the spaces originally designed as data centers, or to integrate an already existing cooling system.
Overhead Heat Exchangers
Generally, a heat exchanger of this type discharges air from the ceiling into the cold aisle whereas the exhaust air rises into the vents in the ceiling; in Close Coupled system cases, the units are positioned directly above the servers, making the cold air delivery and hot air return much more precise.
A system of this type, being positioned vertically, does not need further floor space in the room.
Closed-Loop Configuration
The Closed-Loop cooling typologies act independently from the room they are installed; the rack and the heat exchanger work exclusively with one another, creating an internal microclimate.
In Rack Cooling
The cooling system is adjoint to the server rack and both of them are completely sealed; the solid doors on the enclosure and In-Row Air Conditioners contain the air flow, directing cold air to the server inlet and exhaust air, by using fans, through the cooling coil.
The Close-Loop design allows a very focused cooling at rack level and it is possible to install very dense equipment disregarding the ambient environment, giving flexibility to use unconventional spaces to install the IT equipment.
Efficiency
In the traditional layout, the fans must move air from the perimeter of the room, under the raised floor, and through a perforated floor tile into servers intake. This process requires energy, that varies depending on the typology of the structure. Often, under the raised floor, holdbacks (large cable bundles, conduits) exist, requiring additional fan energy to move the required cold air volume.
Being that in Close Coupled solutions the cooling system and the equipment rack are close to one another, the energy needed is reduced. With an In-Row typology the cooling unit is incorporated in the row of racks and, providing air directly to the row, there are not impediments to consider under the floor. It is estimated, that when integrated, a Close Coupled system can guarantee up to 95% of annual energy reduction compared to a traditional CRAC system of equal cooling capacity.
Some cooling typologies can be associated to fans with variable velocity that adapt in better ways to the workload, so also to the internal temperature of the rack. Having fans that work at the minimum velocity satisfying the requirements of the Data Center is very important for energy consumption.
It is verified that the percentage of energy saved, hence the total energy cost decreases in a more than proportional way with respect to the decrease of air flow (for example, by reducing the fan velocity by 10% we save 27% of energy).
Efficiency is also represented by modularity. With a Close Coupled solution in is indeed possible adding new conditioners in forecast of an increase of the Data Centre capacity.
Despite the fact that some past studies have speculated a very elevated growth of sales of Close Coupled solutions, more recent studies have instead shown a more contained growth. The reason seems to be due to the fact that the In-Row solutions offer significant energy savings as the rack densities are close to the 8-10 kW threshold; today's average densities for medium-sized data centers are instead about 5 kW and energy savings do not fully justify the higher cost of investment for the cooling system.
Refrigerated Water Temperatures
In traditional systems, the refrigerated water supply temperatures typically vary between 6 and 7 °C and cold water is in fact necessary to generate cold air that compensates for the rise that occurs on the floor of the data center, since the cold inlet air and the hot exhaust air interact. However, it is necessary to ensure that the inlet temperature is between 18 and 26.5 °C as established by the ASHRAE.
Some types of Close Coupled systems allow warmer water inlet temperatures due to the proximity of the refrigeration system and the design of the cooling coil while remaining within the guidelines of the ASHRAE.
Since the refrigerators represent 30-40% of the energy consumption of a data center and that this is largely due to mechanical refrigeration, a higher water inlet temperature allows increase the hours in which free cooling is possible and therefore increase the efficiency of the refrigerator.
Close Coupled system of Google Data Centers
For several years now, Google, according to the statements of the vice president of Data Centers, Joseph Kava, restructures the cooling system of its Data Centers every 12 – 18 months, also focusing on Close Coupled type systems.
In 2012 Google published a photo gallery that shows the design of its cooling system, followed by an explanation of Data Center Vice President Joseph Kava, of how it works.
In the data center shown the rooms serve as cold corridors, there is a raised floor but there are no perforated tiles. Cooling occurs in closed corridors with rows of racks on both sides while cooling coils using cold water serve as the ceiling of these warm corridors, which also house the pipes that carry the water to and from the cooling towers housed in another part of the building.
The temperature of the air is generally maintained around 26.5 °C, getting warmer more and more due to the contact with various components, up to about 49 °C. When air is directed by fans in the warm closed corridor where, reaching the top of the room passes through the cooling coil and is cooled to room temperature. The flexible piping connects to the cooling coil at the top of the hot aisle and descends through an opening in the floor and flows under the raised floor.
From the statements of Kava "If we had leaks in the conduits, the water would sink down into our raised floor. We have a lot of experience with this design, and it has never happened a large water loss" , the presence of an emergency system for any water leaks is confirmed. It is also confirmed that the proximity of liquids to the servers is not considered problematic.
Kava also stated, referring to other types of cooling systems with installations on the ceiling to return the hot exhaust air to the air conditioners of the computer room (CRAC) located along the perimeter of the raised floor area, that The whole system is inefficient because the hot air is moved over a long distance while traveling towards the "CRAC", while a Close Coupled system is significantly more efficient.
Bibliography
Bean, J., & Dunlap, K. (2008), Energy Efficient Data Centers: A Close-coupled Row Solution, ASHRAE Journal , 34-40.
EPA. (2007, Agosto 2), EPA Report to Congress on Server and Data Center Energy Efficiency, da Energy Star.
EYP Mission Critical Facilities. (2006, Luglio 26). Energy Intensive Buildings Trends and Solutions: Data Centers , da Critical Facilities Roundtable.
Fontecchio, M. (2009, Gennaio 21), Data Center Air Conditioning Fans Blow Savings Your Way, da Search Data Center.
Sun Microsystems (2008), Energy Efficient Data Centers: The Role of Modularity in Data Center Design, Sun Microsystems.
Notes
DataCenterKnowledge
Cabling install
Close coupled cooling market
External links
How google cools its armada of servers
Metrics and efficiency the future of data centers
Close coupled cooling market
Close-coupled cooling
Data centers | Close Coupled Cooling | [
"Technology"
] | 1,786 | [
"Data centers",
"Computers"
] |
57,769,929 | https://en.wikipedia.org/wiki/Articulated%20soft%20robotics | The term “soft robots” designs a broad class of robotic systems whose architecture includes soft elements, with much higher elasticity than traditional rigid robots. Articulated Soft Robots are robots with both soft and rigid parts, inspired to the muscloloskeletal system of vertebrate animals – from reptiles to birds to mammalians to humans. Compliance is typically concentrated in actuators, transmission and joints (corresponding to muscles, tendons and articulations) while structural stability is provided by rigid or semi-rigid links (corresponding to bones in vertebrates).
The other subgroup in the broad family of soft robots includes continuum soft robots, i.e. robots whose body is a deformable continuum, including its structural, actuating and sensing elements, and take inspiration from invertebrate animals such as octopuses or slugs, or parts of animals, such as an elephant trunk.
Soft robots are often designed to exhibit natural behaviours, robustness and adaptivity, and sometimes mimick the mechanical characteristics of biological systems.
Characteristics and Design
Articulated Soft Robots are built taking inspiration from the intrinsic properties of muscle-skeletal system of vertebrates, whose compliant nature enables humans and animals to effectively and safely perform a large variety of tasks, ranging from walking on uneven terrains, running, and climbing, to grasping and manipulating. It also makes them resilient to highly dynamic, unexpected events such as impacts with the environment. The interplay of the physical properties of vertebrates with the neural sensory-motor control makes motion very energy–efficient, safe and effective.
Robots able to co-exist and co-operate with people and reach or even surpass their performance require a technology of actuators, responsible for moving and controlling the robot, which can reach the functional performance of the biological muscle and its neuro-mechanical control.
The most promising class of actuators for soft robots is the class of Variable Impedance Actuators (VIA) and the subclass of Variable Stiffness Actuators (VSA), complex mechatronic devices that are developed to build passively compliant, robust, and dexterous robots. VSAs can vary their impedance directly at the physical level, thus without the need of an active control capable to simulate different stiffness values. The idea of varying the mechanical impedance of actuation comes directly from natural musculo-skeletal systems, which often exhibit this feature.
A class of Variable Stiffness Actuators achieve simultaneous control of the robot by using two motors antagonistically to manipulate a non-linear spring which acts as an elastic transmission between each of the motors and the moving part, so as to control both the equilibrium point of the robot, and its rigidity or compliance.
Such control model is very similar in philosophy to Equilibrium-Point hypothesis of human motor control. This similitude makes soft robotics an interesting field of research capable to exchange ideas and insights with the research community in motor neuroscience.
Variable Impedance Actuators increase the performance of the soft robotics systems in comparison with the traditional rigid robots in three key aspects: Safety, Resilience and Energy-Efficiency.
Safety in physical human-robot interaction
One of the most revolutionary and challenging features of the class of articulated soft robots is Physical Human-Robot Interaction. Soft robots designed to physically interact with people are designed to coexist and cooperate with humans in applications such as assisted industrial manipulation, collaborative assembly, domestic work, entertainment, rehabilitation or medical applications.
Clearly, such robots must fulfill different requirements from those typically met in conventional industrial applications: while it might be possible to relax requirements on velocity of execution and absolute accuracy, concerns such as safety and dependability become of great importance when robots have to interact with humans.
Safety can be increased in different ways. The classical methods include control and sensorization, e.g. proximity-sensitive skins, or the addition of external soft elements (soft and compliant coverings or airbags placed around the arm for increasing the energy-absorbing properties of protective layers).
Advanced sensing and control can realize a “soft” behavior via software. Articulated Soft Robotics realizes a different approach at increasing the safety level of robots interacting with humans by introducing mechanical compliance and damping directly at the mechanical design level.,“By this approach, researchers tend to replace the sensor-based computation of a behavior and its error-prone realization using active actuator control, by its direct physical embodiment, as in the natural example. Having compliance and damping in the robot structure is by no means sufficient to ensure its safety, as it might indeed be even couterproductive for the elastic energy potentially stored: just like a human arm, a soft robot arm will need intelligent control to make it behave softly as when caressing a baby, or strongly as when punching”.
Resilience
Physical interaction of a robot with its environment can also be dangerous to the robot itself. Indeed, the number of times a robot is damaged because of impacts or force overexertion is rather large.
Resilience to shocks is not only instrumental to achieve viable applications of robots in everyday life, but would also be very useful in industrial environments, substantially enlarging the scope of applicability of robot technology.
Soft robotics technologies can provide solutions that are effective in absorbing shocks and reducing accelerations: soft materials can be used as coverings or even as structural elements in robot limbs, but the main technological challenge remains with soft actuators and transmissions.
Performance and Energy Efficiency
The dynamic behavior of the actuators with controllable compliance guarantees high-performance, lifelike motion and higher energy efficiency than rigid robots.
The natural dynamics of the robot can adapt to the environment, and thus the intrinsic physical behavior of the resulting system is close to the desired motion. In these circumstances, actuators would only have to inject and extract energy into and out of the system for small corrective actions, thus reducing energy consumption.
The idea of embodying desirable dynamics in the physical properties of soft robots finds its natural application in humanoid robots, having to resemble the movements of humans, or in robotic systems realized for prosthetic uses, e.g. anthropomorphic artificial hands. A relevant example of use is in and walking/running robots: indeed, the fact that natural systems change the compliance of their muscular system depending on the gait and environmental conditions, and even during the different phases of the gait, seem to indicate the potential usefulness of Variable Impedance Actuators (VIA) for locomotion. An emerging trend of use of VIA technologies is connected to the growing of a novel category of industrial robots connected to Industry4.0, the Co-Bots.
Exploration of soft robots’ full potential is leading to more and more applications in which the robots overcome conventional- robot performance, and it is widely believed that more applications are yet to come
Related European Projects and Initiatives
SOMA (Soft Manipulation)
SOFTPRO (Synergy-based Open-source Foundations and Technologies for Prosthetics and Rehabilitation)
SOFTHANDS
Natural Natural Machine Motion Initiative (NMMI)
SAPHARI (Safe and Autonomous Physical Human-Aware Robot Interaction)
VIACTORS (Variable Impedance Actuation systems embodying advanced interaction behaviors)
ROBLOG (Cognitive Robot for Automation of Logistic Processes)
THE (The Hand Embodied)
PHRIENDS (Physical Human-Robot Interaction, dependability and safety)
STIFF (Enhancing biomorphic agility through variable stiffness)
See also
Continuum soft robotics
Collaborative Robotics
Human-Robot Interaction
Humanoid robots
Autonomous robots
Personal robot
References
Robots | Articulated soft robotics | [
"Physics",
"Technology"
] | 1,530 | [
"Physical systems",
"Machines",
"Robots"
] |
57,770,802 | https://en.wikipedia.org/wiki/DTaP-Hib%20vaccine | DTaP-Hib vaccine is a combination vaccine whose generic name is diphtheria and tetanus toxoids and acellular pertussis adsorbed with Haemophilus B conjugate vaccine, sometimes abbreviated to DTaP-Hib. It protects against the infectious diseases diphtheria, tetanus, pertussis, and Haemophilus influenzae type B.
A branded formulation was marketed in the US as TriHIBit by Sanofi Pasteur, and administered by using the Sanofi DTaP vaccine Tripedia to reconstitute the Sanofi Hib vaccine ActHIB. TriHIBit and Tripedia were discontinued in 2011.
See also
DPT vaccine
References
Combination vaccines
Diphtheria
Haemophilus
Whooping cough
Tetanus
Vaccines | DTaP-Hib vaccine | [
"Biology"
] | 173 | [
"Vaccination",
"Vaccines"
] |
57,772,997 | https://en.wikipedia.org/wiki/KH%2015D | KH 15D (V582 Monocerotis), described as a winking star because of its unusual dips in brightness, is a binary T Tauri star system embedded in a circumbinary disk. It is a member of the young open cluster NGC 2264, located about from the Sun in the constellation of Monoceros.
Discovery
The unique brightness variations of KH 15D were discovered at Wesleyan University's Van Vleck Observatory in 1995 by Dr. William Herbst and his then-master's student Kristin Kearns. The star was found to alternate, on a 48.37-day period between a brighter "on" state and a fainter "off" state that was less than 4% of the bright state (or up to 96% dimmed). As the years went by, the star spent more and more time "off", such that by 2010 it was always in the faint state, although still periodically variable. In 2012 it unexpectedly began to "wink" on and off again and has now entered a phase where its "on" state is almost twice as bright as it was in the mid-1990s (see light curve).
Hypotheses
A consensus model of this puzzling behavior has emerged, which attributes the winking to the rising and setting of one star relative to the edge of a circumbinary ring that occults part of the orbit. Precession of the ring has caused the gradual evolution of the winking behavior as shown in the diagrams below. Radial velocity measurements confirmed the system as a spectroscopic binary composed of two weak-lined T Tauri stars.
The orbit of the binary system is nearly edge-on to our line of sight and the circumbinary disk is tilted with respect to that orbit, resulting in nodal precession. At the time of the 1996 observation only one star (designated star A) was visible while the occulting ring fully blocked the light from star B. The winking observed was caused by star A rising and setting from behind the ring. By 2010, the ring covered both stars and the system was permanently in the "off" state, being seen only by scattered light off the ring. By 2018, star B was fully uncovered and star A fully occulted. Star B has turned out to be somewhat brighter, hotter and more massive than star A, but the labels have not been changed since this might cause confusion in the literature.
The importance of KH 15D derives from the unique opportunity it provides to study the terrestrial planet formation zone of a protoplanetary disk. From its rate of precession it is known that the occulting ring is located about 3 AU from the stars, which would put it at the asteroid belt in the Solar System. The age of KH 15D is around 3 Myr and its total mass is around 1.5 solar masses, so the system may provide some guidance on when and how planetesimals – the precursors of planets such as the Earth – form. The regular occultations also provide opportunities to study the magnetospheres and photospheres of T Tauri stars in unprecedented detail.
The Disk
Composition
Though the composition of the disk is not known for sure, there has been evidence of methane and water ice features with grain sizes of 1-50 μm.
Bipolar outflows
It has also been observed that there are bipolar outflow jets inclined by 84% coming from the disk itself. Both hydrogen and carbon dioxide outflows have been observed extending from the north and south sides of the disk. These observations have led to an upper mass limit of 3.2266e27 kg for the disk.
Gallery
See also
Disrupted planet
List of stars that have unusual dimming periods
References
T Tauri stars
Monoceros
Spectroscopic binaries
Monocerotis, V582
K-type stars | KH 15D | [
"Astronomy"
] | 791 | [
"Monoceros",
"Constellations"
] |
57,773,393 | https://en.wikipedia.org/wiki/Magic%20string%20%28therapeutic%20aid%29 | Magic string is a psychological therapeutic aid used to make radiotherapy treatment for children less stressful. Without its use, many children need to have general anaesthetic in order to receive their treatment.
Background
Patients receiving radiotherapy have to be alone inside a lead-lined room, since only they can be exposed to the radiation, and also have to stay still during the treatment, with the necessary immobility being achieved through the use of a radiotherapy mask that covers the face and shoulders and is fastened to the treatment bed. Adult patients often find this claustrophobic and it can be particularly distressing for young children. Consequently, many young patients have required sedation with a general anaesthetic in order to meet the requirements of their radiotherapy.
Implementation
The use of magic string, simply a multi-coloured ball of twine, was learned about in 2007 by Lobke Marsden, a play specialist at the Bexley Wing oncology unit of St James's University Hospital in Leeds, as a low-cost solution to the problem of children's difficulties with radiotherapy. One end of the string is held by the patient and the other end by the parent. In 2017, Marsden told Ellen Wallwork of The Huffington Post, "String is perfect for children that really need that connection with their parents. They often give it a little tug, and the parents tug it back from the other room to let the child know they are right there with them", adding that, "It has proven to be the cheapest and one of the best pieces of 'equipment' we own".
Writing in The Guardian in June 2018, Rachel Clarke said, "Cheap as chips and priceless, magic string was created not for profit or personal gain – but simply because someone cared".
References
Play (activity) | Magic string (therapeutic aid) | [
"Biology"
] | 365 | [
"Play (activity)",
"Behavior",
"Human behavior"
] |
57,773,527 | https://en.wikipedia.org/wiki/C25H35N3O | {{DISPLAYTITLE:C25H35N3O}}
The molecular formula C25H35N3O (molar mass: 393.575 g/mol, exact mass: 393.2780 u) may refer to:
Amesergide (LY-237733)
Undecylprodigiosin | C25H35N3O | [
"Chemistry"
] | 75 | [
"Isomerism",
"Set index articles on molecular formulas"
] |
57,774,517 | https://en.wikipedia.org/wiki/Progesterone%20dioxime | Progesterone dioxime, or progesterone 3,20-dioxime (P4-3,20-DO), also known as 3,20-di(hydroxyimino)pregn-4-en-3-one, is a progesterone derivative which was never marketed. It is a progestogen oxime – specifically, the C3 and C20 dioxime of the progestogen progesterone. Progesterone C3 and C20 oxime conjugates have been found to be water-soluble prodrugs of progesterone and pregnane neurosteroids.
See also
List of progestogen esters § Oximes of progesterone derivatives
References
Abandoned drugs
Ketones
Pregnanes
Progestogens
Steroid oximes | Progesterone dioxime | [
"Chemistry"
] | 180 | [
"Ketones",
"Functional groups",
"Drug safety",
"Abandoned drugs"
] |
57,774,849 | https://en.wikipedia.org/wiki/Haemophilus%20B%20and%20hepatitis%20B%20vaccine | Haemophilus B and hepatitis B vaccine is a combination vaccine whose generic name is Haemophilus b conjugate and hepatitis B recombinant vaccine. It protects against the infectious diseases Haemophilus influenzae type B and hepatitis B.
A branded formulation, Comvax, was marketed in the US by Merck. It was discontinued in 2014.
References
Vaccines
Combination vaccines
Haemophilus
Hepatitis B
Withdrawn drugs | Haemophilus B and hepatitis B vaccine | [
"Chemistry",
"Biology"
] | 93 | [
"Vaccines",
"Vaccination",
"Drug safety",
"Withdrawn drugs"
] |
57,775,754 | https://en.wikipedia.org/wiki/Comparison%20of%20Android%20Go%20products |
Android Go products were first showcased at MWC 2018 with six products: Nokia 1, ZTE Tempo Go, Alcatel 1X, General Mobile GM8 Go, Lava Z50, and Micromax Bharat Go. The Blu Vivo Go became the first Android Go device with Android Pie Go edition.
Smartphones
Smartphones.
Tablet computers
A list of tablet computers.
References
Android (operating system) devices
Computing comparisons
Google lists
Lists of mobile phones | Comparison of Android Go products | [
"Technology"
] | 91 | [
"Computing-related lists",
"Computing comparisons",
"Google lists"
] |
57,776,148 | https://en.wikipedia.org/wiki/Ilyobacter%20insuetus | Ilyobacter insuetus is a mesophilic and anaerobic bacterium from the genus of Ilyobacter which has been isolated from marine anoxic sediments from Venice in Italy.
References
Fusobacteriota
Bacteria described in 2002 | Ilyobacter insuetus | [
"Biology"
] | 54 | [
"Bacteria stubs",
"Bacteria"
] |
57,776,199 | https://en.wikipedia.org/wiki/Leptotrichia%20trevisanii | Leptotrichia trevisanii is an aerotolerant, filamentous and non-motile bacterium from the genus of Leptotrichia which has been isolated from human blood.
References
Fusobacteriota
Bacteria described in 2002 | Leptotrichia trevisanii | [
"Biology"
] | 56 | [
"Bacteria stubs",
"Bacteria"
] |
57,776,997 | https://en.wikipedia.org/wiki/5%CE%B1-Dihydroethisterone | 5α-Dihydroethisterone (5α-DHET; developmental code name HE-3562) is an active metabolite of the formerly clinically used but now-discontinued progestin ethisterone and the experimental and never-marketed hormonal antineoplastic agent ethynylandrostanediol (HE-3235). Its formation from its parent drugs is catalyzed by 5α-reductase in tissues that express the enzyme in high amounts like the liver, skin, hair follicles, and prostate gland. 5α-DHET has significant affinity for steroid hormone receptors and may contribute importantly to the activities of its parent drugs.
Pharmacology
Pharmacodynamics
The affinity of 5α-DHET for the androgen receptor (AR) is relatively high, in the range of 38 to 100% of that of dihydrotestosterone (DHT). A study found that, similarly to norethisterone and its 5α-reduced metabolite 5α-dihydronorethisterone, 5α-DHET showed increased affinity for the AR but decreased androgenic potency relative to ethisterone (Ki = 16.1 nM for 5α-DHET and 101.1 nM for ethisterone, a 6-fold difference in affinity). The decreased androgenic activity of 5α-DHET in spite of increased affinity for the AR relative to ethisterone suggests that it has comparatively reduced efficacy as an agonist of the receptor, analogously to selective androgen receptor modulators (AR partial agonists) and antiandrogens (AR antagonists). 5α-DHET has relatively low affinity for the progesterone receptor, only about 12% of that of the progestogen progesterone. This is significantly less than that of ethisterone, which has been found to bind to the receptor with an affinity of 35% of that of progesterone. Conversely, it has relatively high affinity for the glucocorticoid receptor, about 120% of that of the corticosteroid dexamethasone. In regards to the estrogen receptors, 5α-DHET has weak affinity for the ERα of about 3.5% of that of estradiol, and does not bind to the ERβ (Ki > 10 μM).
In addition to steroid hormone receptors, 5α-DHET has very high affinity for sex hormone-binding globulin (Kd = 0.18 nM), an androgen and estrogen binding and transport protein that has the effect of intermittently inactivating steroid hormones (but also prolonging their half-life in the body). Its affinity for this protein is among the highest of any known compound and has been found to be roughly equal to that of DHT and mesterolone (1α-methyl-DHT). This property may contribute to the androgenic activity of 5α-DHET's parent drug ethisterone by displacing endogenous androgens like testosterone and DHT from SHBG.
Pharmacokinetics
Metabolism studies of ethynylandrostanediol revealed that 5α-DHET can be metabolized via C7β and C16α hydroxylation.
Chemistry
5α-DHET, also known as 5α-dihydro-17α-ethynyltestosterone (17α-ethynyl-DHT) as well as 17α-ethynyl-5α-androstan-17β-ol-3-one or 5α,17α-pregn-20-yn-17β-ol-3-one, is a synthetic androstane steroid and a derivative of testosterone. It is specifically the combined derivative of 5α-dihydrotestosterone (DHT) and ethisterone (17α-ethynyltestosterone). The steroid is also closely related to ethynylandrostanediol (17α-ethynyl-5α-androstane-3α,17β-diol).
Analogues
Some closely related synthetic 5α-reduced steroid metabolites include 5α-dihydronandrolone, 5α-dihydronormethandrone, 5α-dihydronorethandrolone, 5α-dihydronorethisterone, and 5α-dihydrolevonorgestrel, as well as 19-norandrosterone and 19-noretiocholanolone.
Derivatives
The steroidal antiandrogen zanoterone (WIN-49596), which was investigated in the 1990s for the treatment of benign prostatic hyperplasia but was never marketed, was derived from 5α-DHET. In terms of chemical structure, it is 5α-DHET with a pyrazole ring-containing moiety fused at the C2 and C3 positions.
Synthesis
A partial synthesis of 5α-DHET from androstenedione has been published.
References
5α-Reduced steroid metabolites
Ethynyl compounds
Anabolic–androgenic steroids
Androstanes
Glucocorticoids
Human drug metabolites
Ketones
Progestogens
Synthetic estrogens | 5α-Dihydroethisterone | [
"Chemistry"
] | 1,139 | [
"Ketones",
"Chemicals in medicine",
"Functional groups",
"Human drug metabolites"
] |
57,777,800 | https://en.wikipedia.org/wiki/Ministry%20of%20Energy%20%28Tanzania%29 | The Ministry of Energy is the government ministry of Tanzania which is responsible for facilitating the development of the energy sectors.
History
The Ministry was formed in 2017 after the preceding ministry, the Ministry of Energy and Minerals, was split by President John Magufuli to improve supervision.
Recent
As of September 1 2023, the ministry has been headed by Hon. Dkt Doto Mashaka Biteko, who is the Deputy Prime Minister and Minister of Energy, Hon. Judith Salvio Kapinga as the Deputy Minister for Energy and Engl. Felschemi Jossen Mramba as the Permanent Secretary.
References
External links
E
Tanzania
Energy in Tanzania | Ministry of Energy (Tanzania) | [
"Engineering"
] | 132 | [
"Energy organizations",
"Energy ministries"
] |
57,777,952 | https://en.wikipedia.org/wiki/Ricinine | Ricinine is a toxic alkaloid found in the castor plant. It can serve as a biomarker of ricin poisoning. It was first isolated from the castor seeds by Tuson in 1864.
Ricinine has insecticidal effects.
It sublimes between 170 and 180 °C at 20 mmHg. It does not form salts, and is precipitated in iodine or mercuric chloride solutions, but not in Mayer's reagent.
It can be hydrolyzed to methanol and ricininic acid by alkali.
See also
Ricin
References
Alkaloids
2-Pyridones
Nitriles
Ethers
Ricin
Plant toxins
Castor oil plant | Ricinine | [
"Chemistry"
] | 147 | [
"Biomolecules by chemical classification",
"Chemical ecology",
"Natural products",
"Functional groups",
"Plant toxins",
"Organic compounds",
"Ethers",
"Nitriles",
"Alkaloids"
] |
57,778,006 | https://en.wikipedia.org/wiki/Progesterone%203-oxime | Progesterone 3-oxime (P4-3-O), also known as 3-(hydroxyimino)pregn-4-en-3-one, is a progesterone derivative which was never marketed. It is a progestogen oxime – specifically, the C3 oxime of the progestogen progesterone. Progesterone C3 and C20 oxime conjugates, like progesterone 3-(O-carboxymethyl)oxime, have been found to be water-soluble prodrugs of progesterone and pregnane neurosteroids.
See also
List of progestogen esters § Oximes of progesterone derivatives
References
Abandoned drugs
Ketones
Pregnanes
Progestogens
Steroid oximes
Ketoximes | Progesterone 3-oxime | [
"Chemistry"
] | 183 | [
"Ketones",
"Functional groups",
"Drug safety",
"Abandoned drugs"
] |
57,778,150 | https://en.wikipedia.org/wiki/Cole%20equation%20of%20state | An equation of state introduced by R. H. Cole
where is a reference density, is the adiabatic index, and is a parameter with pressure units.
References
External links
Cole equation of state article at sklogwiki
Equations of state | Cole equation of state | [
"Physics",
"Chemistry"
] | 50 | [
"Physical chemistry stubs",
"Statistical mechanics",
"Equations of state",
"Equations of physics"
] |
70,189,737 | https://en.wikipedia.org/wiki/Blank%20value | A blank value in analytical chemistry is a measurement of a blank. The reading does not originate from a sample, but the matrix effects, reagents and other residues. These contribute to the sample value in the analytical measurement and therefore have to be subtracted.
The limit of blank is defined by the Clinical And Laboratory Standards Institute as the highest apparent analyte concentration expected to be found when replicates of a sample containing no analyte are tested.
See also
Blank (solution)
References
Analytical chemistry | Blank value | [
"Chemistry"
] | 100 | [
"nan",
"Analytical chemistry stubs"
] |
70,190,096 | https://en.wikipedia.org/wiki/Price-Jones%20curve | A Price-Jones curve is a graph showing the distribution of diameters of red blood cells. Higher diameter may be seen in pernicious anaemia, while lower diameter may be seen after haemorrhage.
Medical uses
A Price-Jones curve can be used in the diagnosis of anaemia. Price-Jones curves usually vary both by average red blood cell size, and the distribution of sizes.
Interpretation of results
Higher red blood cell diameter and wider variation in size are often seen in pernicious anaemia. Lower diameter with normal variation in size are often seen after haemorrhage. A higher variation in size is known as anisocytosis.
Procedure
A blood smear can be used to view individual red blood cells. The diameter of each red blood cell can be measured, which is usually analogous to volume. This is usually performed automatically by particle counters. Data is then converted into a histogram. This can be used to assess red blood cell distribution width (RDW).
History
Cecil Price-Jones first proposed using the Price-Jones curve in a 1922 paper. It has been used for assessing red blood cells since then.
References
Blood tests
Statistical charts and diagrams
Estimation of densities
Frequency distribution
Nonparametric statistics | Price-Jones curve | [
"Chemistry",
"Mathematics"
] | 251 | [
"Blood tests",
"Functions and mappings",
"Mathematical objects",
"Mathematical relations",
"Frequency distribution",
"Chemical pathology"
] |
70,190,130 | https://en.wikipedia.org/wiki/Diffusion%20tube | A diffusion tube is a scientific device that passively samples the concentration of one or more gases in the air, commonly used to monitor average air pollution levels over a period ranging from days to about a month. Diffusion tubes are widely used by local authorities for monitoring air quality in urban areas, in citizen science pollution-monitoring projects carried out by community groups and schools, and in indoor environments such as mines and museums.
Construction and operation
A diffusion tube consists of a small, hollow, usually transparent, acrylic or polypropylene plastic tube, roughly 70mm long, with a cap at each end. One of the caps (coloured white) is either completely removed to activate the tube (in the case of nitrogen dioxide sampling) or contains a filter allowing in just the gas being studied. The other cap (a different colour) contains metal mesh discs coated with a chemical reagent that absorbs the gas being studied as it enters the tube. Tubes that work this way are also known as Palmes tubes after their inventor, American chemist Edward Palmes, who described using such a tube as a personal air quality sensor in 1976.
During operation, the tube is opened and vertically fastened with cable ties to something like a lamp-post or road sign, with the open end facing down, and the closed, coloured cap at the top. The gas being monitored, which is at a higher concentration in the atmosphere, diffuses into the bottom of the tube and is quickly absorbed by the chemical cap. As it is absorbed, the process of diffusion continues. After a fixed period of time (typically from two weeks to a month), the tube is sealed up and sent away to a laboratory for analysis. The atmospheric concentration of the gas being studied can be calculated using the amount captured and Fick's laws of diffusion.
Diffusion tubes can be used to sample various different gases, including oxides of nitrogen (nitrogen dioxide and nitric oxide), sulphur dioxide, ammonia, and ozone. Although tubes sampling these gases all work through the same process of molecular diffusion, there are important differences. Nitrogen dioxide tubes use triethanolamine, TEA, as the absorbing (reagent) chemical, for example, while hydrogen sulphide tubes are opaque (rather than transparent) to prevent ultraviolet light from degrading the chemicals inside. Some types of tube can sample multiple gases at the same time.
Advantages and disadvantages
Diffusion tubes are reasonably accurate, relatively cheap, easy to use, extremely compact, passive (they need no power source), and have a fairly long shelf life; with careful positioning, they can be deployed more or less anywhere, indoors or outdoors. They give a reasonable indication of the long-term, average concentration of a pollutant gas, such as nitrogen dioxide, and they make it easy to compare average pollution levels in different places or at different times. Often, a series of tubes are mounted in exactly the same place for consecutive months of the year to enable longer-term comparisons of pollution levels. It's also common for local authorities to mount a number of tubes in different places over the same time period so pollution hotspots in towns and cities can be identified.
Since diffusion tubes are designed to be left in place for days or weeks at a time, they don't indicate shorter-term fluctuations of the pollutant being studied, such as the rising and falling levels of gas during the day, the difference between one day and the next or between weekdays and weekends, or the number of times guideline pollution levels are exceeded while they're in place. They're also much less accurate than the highly sensitive, automated monitoring equipment used in roadside pollution monitoring cabins. Sources of inaccuracy include air turbulence (caused by things like wind movements or air conditioners), pollution from building ventilation systems, ultraviolet light (theoretically absorbed by the plastic tube), and other pollutants.
References
Air pollution
Atmospheric chemistry
Measuring instruments | Diffusion tube | [
"Chemistry",
"Technology",
"Engineering"
] | 800 | [
"nan",
"Measuring instruments"
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70,192,699 | https://en.wikipedia.org/wiki/ScGET-seq | Single-cell genome and epigenome by transposases sequencing (scGET-seq) is a DNA sequencing method for profiling open and closed chromatin. In contrast to single-cell assay for transposase-accessible chromatin with sequencing (scATAC-seq), which only targets active euchromatin, scGET-seq is also capable of probing inactive heterochromatin.
This is achieved through the use of TnH, which is created by linking the chromodomain (CD) of heterochromatin protein-1-alpha (HP-1) to the Tn5 transposase. TnH is then able to target histone 3 lysine 9 trimethylation (H3K9me3), a marker for heterochromatin.
Akin to RNA velocity, which uses the ratio of spliced to unspliced RNA to infer the kinetics of changes in gene expression over the course of cellular development, the ratio of TnH to Tn5 signals obtained from scGET-seq can be used to calculate chromatin velocity, which measures the dynamics of chromatin accessibility over the course of cellular developmental pathways.
History
Transcriptional regulation is tightly linked to chromatin states. Chromatin that is open, or permissive to transcription, make up only 2-3% of the genome, but encompass 94.4% of transcription factor binding sites. Conversely, more tightly packed DNA, or heterochromatin, is responsible for genome organization and stability. Chromatin density also changes over the course of cellular differentiation processes, but there is a lack of high-throughput sequencing methods for directly assaying heterochromatin.
Many genomic-related diseases such as cancer are highly linked to changes in their epigenome. Cancers in particular are characterized by single-cell heterogeneity, which can drive metastasis and treatment resistance. The mechanisms that underlie these processes are still largely unknown, although the advent of single-cell technologies, including single-cell epigenomics, has contributed greatly to their elucidation.
In 2015, ATAC-seq, which uses the Tn5 transposase to fragment and tag accessible chromatin, or euchromatin, for sequencing, became feasible at the single-cell resolution. scGET-seq builds upon this technology by also providing information on heterochromatin, providing a more comprehensive look at chromatin structure and dynamics within each cell.
Methods
Sample preparation
Sample preparation for scGET-seq starts with obtaining a suspension of nuclei from cells using a method appropriate for the starting material.
The next step is to produce the TnH transposase. Tn5 is a transposase that cuts and ligates adapters to genomic regions unbound by nucleosomes (open chromatin). HP-1a is a member of the HP1 family and is able to recognize and specifically bind to H3K9me3. Its chromodomain uses an induced-fit mechanism for recognizing this chromatin modification. Linking the first 112 amino acids of HP-1a containing the chromodomain to Tn5 using a three poly-tyrosine-glycine-serine (TGS) linker leads to the creation of the TnH transposase, which is capable of targeting heterochromatin marked by H3K9me3.
Library preparation is done using a modified protocol for single-cell ATAC-seq, where the nuclei suspension is sequentially incubated with the Tn5 transposase first, and then TnH.
Data analysis
The goals of the data analysis are:
To identify and characterize distinct cell populations using clustering
To profile chromatin accessibility across the genome
To predict copy-number variants and single-nucleotide variants
Pre-processing
Post-sequencing, reads need to be demultiplexed and mapped to the appropriate reference genome. Duplicated reads are identified and removed.
"Peaks", or regions in the DNA enriched in the number of reads mapped, are identified.
Quality control is performed, and cells with low numbers of reads or few detected features are filtered out.
Four count matrices (matrices where each column is a cell and each row is a feature) are generated: Tn5-dhs, Tn5-complement, TnH-dhs and TnH-complement, representing signal from accessible and compacted chromatin.
Analysis
Dimension reduction, visualization and clustering
Each of the matrices are filtered of shared regions and then normalized and log2 transformed. Linear dimension reduction is done using principal component analysis (PCA). Groups of cells are identified using a k-NN algorithm and Leiden algorithm. Finally, the four matrices are combined using matrix factorization and UMAP reduction.
Cell identification annotation
There are two approaches to cell identity annotation: Annotation based on feature annotation of ATAC peaks, and annotation based on integration with reference scRNA-seq data.
Applications
Current
By using the ratio of Tn5 to TnH signals, quantitative values describing how quickly and in what direction chromatin remodelling is taking place can be calculated (chromatin velocity). By isolating regions that are most dynamic and identifying which transcription factors bind there, chromatin velocity can be used to infer the dynamic epigenetic processes happening within a given cell and the contributions of various transcription factors to those processes.
Future
Chromatin remodelling precedes changes in gene expression and enhances the understanding of trajectories and mechanisms of cellular changes. Thus, platforms and tools for integration of multimodal data are areas of active research Incorporating temporal and directionality elements through integration of chromatin velocity with RNA velocity has been proposed to reveal even more information about differentiation pathways.
Limitations
scGET-seq has some of the same limitations as scATAC-seq. Both processes require nuclei samples from viable cells, and high cellular viability. Low cellular viability leads to high background DNA contamination that do not accurately represent authentic biological signals. Additionally, the sparsity and noisy nature of scATAC-seq and scGET-seq data makes analysis challenging, and there is no consensus yet on how to best manage this data
Another limitation is that scGET-seq still needs the validation of SNVs results by bulk genome sequencing. Even though there is a high correlation of mutations between bulk exome sequencing and scGET-seq results, scGET-seq fails to capture all exome SNVs.
References
Molecular biology techniques | ScGET-seq | [
"Chemistry",
"Biology"
] | 1,383 | [
"Molecular biology techniques",
"Molecular biology"
] |
70,193,166 | https://en.wikipedia.org/wiki/Michner%20Plating%20site | The Michner Plating Co.–Mechanic Street Site, as dubbed by the EPA, is a 140,000 square foot industrial complex that sits upstream to the Grand River in Jackson, Michigan. on the corner of N. Mechanic Street and W. Trail Street.
Architecture
The first portion of the main structure was completed between 1907 and 1910, three stories, and made out of reinforced concrete. During the site's main expansion in 1920, a new brick-wall, steel-framed, wood-floored building was annexed onto this. A new basement with access doors was added along with that initial expansion movement.
Following this, two new similarly structured buildings were constructed. These extensions, utilizing large attic spaces to trap heat in winter, and shingles to absorb heat in summer. Architecture modernized the plant for agriculture, allowing seeds on the third floor to stay warm in winter during packaging, in which produce was exposed. New boilers were added, and placed in the northern basement.
After being converted to a plating-facility, the open floor plan was used for machinery, mostly the ceiling-mounted conveyor line which wrapped around the first and second floors. New fiberglass was installed over windows on the building, this originally would prevent metal degradation from UV light.
Isbell's Seeds
The very first industrial buildings on this site were constructed in the late 19th and early 20th century; these companies were Weeks Drug & Chemical, Lewis Blessings Cigar & Paper Box, and Novelty Manufacturing.
By 1920 Lewis Blessings and Weeks Drug & Chemicals' property on Mechanic Street had been acquired by S.M. Isbell Seed Co.
Isbell Seed, was Michigan's biggest supplier of agricultural produce, specifically beans at the time. After the acquisition of the buildings, the S.M. Isbell Company preceded in demolition of multiple structures on site, excluding Weeks's three-story storage building. Isbell Seed expanded the Weeks storage building until 1930, when Isbell evidently fell victim to the Great depression.
When looking over that site today viewers are able to observe the original Isbell signs that'd been painted on the building's facade, standing the test of time.
Michner acquisition
In 1935 the three-story complex was purchased by Joseph Michner, in which he would found Michner Plating Corp. The company manufactured and plated automobile parts, particularly seat belts and other small parts. Engraving, heat treating, chrome, and electroplating also made up the bulk of manufacturing that occurred at Michner Plating Co.
The Michner Plating Corporation renovated the Isbell buildings for plating, repainting them with the Michner name, and continue the expansion of the buildings. The company also bought the former Novelty Mfg., site allowing them to expand on the north end of the site.
Michner Adjusts Properties for Reuse:
1936: New chrome line building with conveyor access to the former Isbell structures
1940s: Northern loading area restructured with more coverage and access
1962: Two floor office building and loading room, under new management of Walter Michner
1963: Former Isbell Complex sold to SalCo Engineering & Manufacturing
1965: Nickel & zinc plating lines expansion, heat treatment machine installed
Later years
After the 1963 site split Michner Plating Co. began receiving numerous OSHA violation notices for their Mechanic St. site, under handling of chemicals and chemical disposal. In 2007 Michner ceased operations at the Mechanic St. site because of a high operation cost with small outcome, during continuous increase in demand for plating. This resulted in the relocation to their Angling Rd. property, where Jason Michner would take over company operations. The building's vacancy allowed for Michner to salvage metals by cutting pipes, which sparked a small fire in the unused, wood-beam building. Michner Plating Co. later entered foreclosure in 2013 due to $1.6 million unpaid back-taxes.
SalCo relocated services to Micor Drive in 2015 following the EPA's investigation into the site; the investigation concluded with the discovery of over '1,100 drums, vats, totes, and other containers potentially containing cyanide, zinc cyanide, nickel chloride, chromic acid, hydrogen peroxide, sulfuric acid, ignitable wastes, reactive wastes and other chemicals'. Groundwater soil tests were also performed across the site for PFAS, outsourcing from a flooded basement used to store industrial materials, a hazard due to its proximity to the Grand River and private wells, achieving a Hazardous Ranking System score of 39.12.
In 2016 the US Nuclear Regulatory Commission inquired about former-tenant Novelty Manufacturing's business in radium isotopes, used in their foot-warmer contraption, which could potentially harm the fragile environment around the facility. In 2018, after performing a radiological survey, the NRC informed the EPA that no such radium isotope contamination had been found during the survey.
Current status
During the late 2010s the abandoned buildings became a popular spot to vandalize and explore. Due to Jackson's graffiti ordinance none of the graffiti, has been repainted since being obtained by Jackson County. The complex seems to be very popular among local underground photographers; some intruders have brought grills into the buildings.
In 2021 a portion of tar concrete roof in the north building collapsed due to severe weathering, and previous neglect. The southern portion that was previously occupied by SalCo took on flooding, asbestos-insulated piping was damaged, and bricks fell. The entire Michner Plating Site is still too unsafe for industrial use, but has been considered for partial redevelopments in its strategic location.
The EPA resumed cleanup in 2021, and designated Michner Plating as a Superfund Site; citing numerous barrels containing industrial contaminants, buried within the building's foundation. Jackson County is developing a plan to demolish the building for site reuse by December 2022. All entry points in both buildings have been sealed for the cleanup process to prevent interruption.
References
Brick buildings and structures in the United States
Buildings and structures completed in 1965
Buildings and structures in Jackson County, Michigan
Mill architecture
Superfund sites in Michigan
Unused buildings in Michigan | Michner Plating site | [
"Engineering"
] | 1,254 | [
"Mill architecture",
"Architecture"
] |
70,193,217 | https://en.wikipedia.org/wiki/BullSequana | BullSequana is the brand name of a range of high performance computer systems produced by Atos.
The range includes
BullSequana S series - a modular compute platform optimised for AI and GPU-intensive tasks.
BullSequana X series - supercomputers which are claimed to operate at exascale
References
Computer systems | BullSequana | [
"Technology",
"Engineering"
] | 73 | [
"Computer engineering",
"Computer hardware stubs",
"Computer systems",
"Computer science",
"Computing stubs",
"Computers"
] |
70,193,952 | https://en.wikipedia.org/wiki/Lattice%20confinement%20fusion | Lattice confinement fusion (LCF) is a type of nuclear fusion in which deuteron-saturated metals are exposed to gamma radiation or ion beams, such as in an IEC fusor, avoiding the confined high-temperature plasmas used in other methods of fusion.
History
In 2020, a team of NASA researchers seeking a new energy source for deep-space exploration missions published the first paper describing a method for triggering nuclear fusion in the space between the atoms of a metal solid, an example of screened fusion. The experiments did not produce self-sustaining reactions, and the electron source itself was energetically expensive.
Technique
The reaction is fueled with deuterium, a widely available non-radioactive hydrogen isotope composed of one proton, one neutron, and one electron. The deuterium is confined in the space between the atoms of a metal solid such as erbium or titanium. Erbium can indefinitely maintain 1023 cm−3 deuterium atoms (deuterons) at room temperature. The deuteron-saturated metal forms an overall neutral plasma. The electron density of the metal reduces the likelihood that two deuterium nuclei will repel each other as they get closer together.
A dynamitron electron-beam accelerator generates an electron beam that hits a tantalum target and produces gamma rays, irradiating titanium deuteride or erbium deuteride. A gamma ray of about 2.2 megaelectron volts (MeV) strikes a deuteron and splits it into proton and neutron. The neutron collides with another deuteron. This second, energetic deuteron can experience screened fusion or a stripping reaction.
Although the lattice is notionally at room temperature, LCF creates an energetic environment inside the lattice where individual atoms achieve fusion-level energies. Heated regions are created at the micrometer scale.
Screened fusion
The energetic deuteron fuses with another deuteron, yielding either a 3helium nucleus and a neutron or a 3hydrogen nucleus and a proton. These fusion products may fuse with other deuterons, creating an alpha particle, or with another 3helium or 3hydrogen nucleus. Each releases energy, continuing the process.
Stripping reaction
In a stripping reaction, the metal strips a neutron from accelerated deuteron and fuses it with the metal, yielding a different isotope of the metal. If the produced metal isotope is radioactive, it may decay into another element, releasing energy in the form of ionizing radiation in the process.
Palladium-silver
A related technique pumps deuterium gas through the wall of a palladium-silver alloy tubing. The palladium is electrolytically loaded with deuterium. In some experiments this produces fast neutrons that trigger further reactions. Other experimenters (Fralick et al.) also made claims of anomalous heat produced by this system.
Comparison to other fusion techniques
Pyroelectric fusion has previously been observed in erbium hydrides. A high-energy beam of deuterium ions generated by pyroelectric crystals was directed at a stationary, room-temperature or target, and fusion was observed.
In previous fusion research, such as inertial confinement fusion (ICF), fuel such as the rarer tritium is subjected to high pressure for a nano-second interval, triggering fusion. In magnetic confinement fusion (MCF), the fuel is heated in a plasma to temperatures much higher than those at the center of the Sun. In LCF, conditions sufficient for fusion are created in a metal lattice that is held at ambient temperature during exposure to high-energy photons. ICF devices momentarily reach densities of 1026 cc−1, while MCF devices momentarily achieve 1014.
Lattice confinement fusion requires energetic deuterons and is therefore not cold fusion.
See also
Inertial confinement fusion
Magnetized target fusion
Pyroelectric fusion
References
Nuclear fusion
Nuclear fusion reactions
NASA research centers
Space exploration | Lattice confinement fusion | [
"Physics",
"Chemistry",
"Astronomy"
] | 809 | [
"Outer space",
"Space exploration",
"Nuclear fusion reactions",
"Nuclear physics",
"Nuclear fusion"
] |
70,194,962 | https://en.wikipedia.org/wiki/Ribonucleoprotein%20Networks%20Analyzed%20by%20Mutational%20Profiling | Ribonucleoprotein Networks Analyzed by Mutational Profiling (RNP-MaP) is a strategy for probing RNA-protein networks and protein binding sites at a nucleotide resolution. Information about RNP assembly and function can facilitate a better understanding of biological mechanisms. RNP-MaP uses NHS-diazirine (SDA), a hetero-bifunctional crosslinker, to freeze RNA-bound proteins in place. Once the RNA-protein crosslinks are formed, MaP reverse transcription is then conducted to reversely transcribe the protein-bound RNAs as well as introduce mutations at the site of RNA-protein crosslinks. Sequencing results of the cDNAs reveal information about both protein-RNA interaction networks and protein binding sites.
Strategy
Components
RNA-MaP involves three major components:
Ribonucleoproteins (RNPs): complexes made up of RNAs and RNA-binding proteins (RBPs)
NHS-diazirine (SDA): a cell permeable crosslinking reagent. SDA contains two reactive groups - a diazirine and a succinimidyl ester. The reaction between succinimidyl esters and amine groups (e.g. lysine side chains) results in peptide bonds (or amide bonds). When exposed to UV light with a wavelength of 365 nm, an intermediate broadly reactive toward nucleotide riboses and bases is formed. As a result, proteins are crosslinked with RNA by the SDA linker.
Mutational profiling (MaP): a method using reverse transcriptase with relaxed fidelity to incorporate modified residues at protein-RNA binding sites.
Workflow
Long-wavelength UV and SDA reagents are first supplied to living cells to crosslink protein residues with RNA by forming amide bonds between amine groups of lysine (or arginine) residues and succinimidyl esters. Next, cells containing crosslinked RNPs are lysed and the RNA-bound proteins are digested into peptide adducts. MaP reverse transcription is then performed to label the protein-RNA binding sites through peptide adduct-induced mutations. Sequencing of the mutation-containing cDNA product will reveal the mutation sites (or RNP-MaP sites) and the correlations between the RNP-MaP sites are computationally determined using 3-nucleotide windows.
Analysis
RNP-MaP site identification
RNP-MaP sites are defined as protein bound nucleotides. SDA and UV treated and UV only treated sample sequence reads are aligned and mutations are counted using ShapeMapper2 software. The SDA or RNP-MaP reactivity for a nucleotide is the ratio of the crosslinked (SDA and UV treated) mutational frequency to the un-crosslinked (UV only) mutation frequency. Using differential mutational signatures, RNP-MaP sites are identified based on universal normalization factors and thresholds on each RNA nucleotide (U, A, C, and G) derived from analysis of ribonucleoproteins of known structure.
A nucleotide is identified as a RNP-MaP site if it passes three filters:
The number of mutation events in the SDA + UV-treated sample is at least 50 greater than the UV-treated sample.
Site reactivities must exceed the nucleotide-dependent thresholds () that are empirically defined as:
, where
is the nucleotide U, A, C, or G
is the background threshold defined by the 90% reactivity values of nucleotides in a >10Å group
is the median of all reactivities for all nucleotides
is the standard deviation of reactivities for all nucleotides
The calculated Z-factor is greater than zero
The calculated Z-factor is defined as
, where
is the mutation rate of a nucleotide treated with SDA and UV and is the mutation rate of a nucleotide treated with UV only
, where is treatment (SDA + UV or UV only)
Protein-RNA interaction network identification
Protein-RNA interactions networks are identified using RNP-MaP correlations since multiple crosslink sites can be detected for a single RNA molecule. RNP-MaP correlations provide a complementary measure of protein binding to RNA independent of RNP-MaP sites. They are identified using a G-test framework known as RingMapper.
RNP-MaP correlations require a single RNA molecule to form at least two crosslinks and arise from any of three scenarios:
A single protein binds to two locations of one RNA
Two proteins that interact and bind to two locations on one RNA
Two proteins are deposited on two locations on one RNA by a coordinated assembly process
Using RNP-MaP correlations, a network of protein-RNA interaction sites is found and can then be used for functional analysis.
Related methods
Cross-linking immunoprecipitation (CLIP)
CLIP analyzes protein interactions with RNA by combining UV cross-linking and immunoprecipitation. CLIP-based techniques are able to map RNA binding protein binding sites of interest on a genome-wide scale.
There are many CLIP-based methods including:
HITS-CLIP (High-throughput sequencing of RNA isolated by crosslinking immunoprecipitation or CLIP-seq)
PAR-CLIP (Photoactivatable ribonucleoside-enhanced cross-linking and immunoprecipitation)
iCLIP (Individual nucleotide-resolution cross-linking and immunoprecipitation)
eCLIP (Enhanced cross-linking and immunoprecipitation followed by high-throughput sequencing)
sCLIP (Simple cross-linking and immunoprecipitation)
Mass spectrometry
Quantitative mass spectrometry (MS) (or quantitative proteomics) can be used to discover RNA-binding proteins (RBPs) bound to RNA. Labeling MS methods involve the differential use of stable isotope labels or chemical tagging of proteins in samples and controls. This is used to obtain enrichment scores and true binding partners through the ratio of labeled peptides. Label-free MS methods are able to identify proteins in samples and controls. In order to distinguish true binding partners for nonspecific proteins, analytical tools used alongside spectral count data from non-quantitative MS are used to score the probability of a true RBP-RNA interaction
Advantages and Limitations
Advantages
RNP-MaP can help reveal functionally important RNA-protein binding networks through binding site density and interconnectivity independent of previous knowledge of interacting proteins. Because of the unbiased nature of the analysis, RNP-MaP is able to detect conserved RNA-protein interactions between species.
RNP-MaP is also able to facilitate the characterization of functionally critical elements in large non-coding RNAs or even viral RNAs.
Limitations
As a standalone technique, RNP-MaP cannot be used to determine protein-RNA binding mechanisms or protein identities. In order to do so, RNP-MaP must be used in conjunction with other techniques such as CLIP and mass spectrometry.
RNP-MaP requires extremely high read-depths for analysis. To identify RNP-MaP sites, 1000x sequencing coverage is required, while RNP-MaP correlation sites require 10,000x sequencing coverage.
There are severe limitations on the ability to characterize RNP-MaP correlations between distant (>500 nucleotides) RNP-MaP sites. This is due to limitations of MaP reverse transcription processivity (500-600 nucleotides) and sequencing instrument clustering (<1,000 nucleotides).
References
Genetics techniques
RNA | Ribonucleoprotein Networks Analyzed by Mutational Profiling | [
"Engineering",
"Biology"
] | 1,587 | [
"Genetics techniques",
"Genetic engineering"
] |
70,195,045 | https://en.wikipedia.org/wiki/Phaeotremella | Phaeotremella is a genus of fungi in the family Phaeotremellaceae. All Phaeotremella species are parasites of other fungi and produce anamorphic yeast states. Basidiocarps (fruit bodies), when produced, are gelatinous and are colloquially classed among the "jelly fungi". Fifteen or so species of Phaeotremella are currently recognized worldwide. Tremella sanguinea, shown to be a Phaeotremella species by DNA sequencing, is cultivated in China as an ingredient in traditional Chinese medicine.
Taxonomy
History
The genus Phaeotremella was originally created by British mycologist Carleton Rea to accommodate Phaeotremella pseudofoliacea, a fungus that resembled a Tremella species but had brown rather than white basidiospores. Later authors considered this to be a mistaken observation and placed Phaeotremella in synonymy with Tremella and its type species in synonymy with Tremella foliacea.
Molecular research, based on cladistic analysis of DNA sequences, has however shown that Tremella is paraphyletic (and hence artificial). A different generic name was therefore required for a group of species not closely related to Tremella mesenterica (the type species of Tremella) and Phaeotremella was selected as the earliest such name available. As a result, the current definition of Phaeotremella is not the same as Rea's original concept. The type species, P. pseudofoliacea, has been placed in synonymy with Phaeotremella frondosa.
Description
Fruit bodies (when present) are gelatinous. In some species they are small (under 5 mm across) and pustular to pulvinate (cushion-shaped). In others they are much larger (up to 150 mm across) and may be variously lobed or foliose (with leaf-like or seaweed-like fronds). Several Phaeotremella species are, however, only known from their yeast states.
Microscopic characters
Phaeotremella species produce hyphae that are typically (but not always) clamped and have haustorial cells from which hyphal filaments seek out and penetrate the hyphae of the host. The basidia are "tremelloid" (globose to ellipsoid and vertically or diagonally septate), giving rise to long, sinuous sterigmata or epibasidia on which the basidiospores are produced. These spores are smooth, globose to ellipsoid, and germinate by hyphal tube or by yeast cells. Conidiophores are often present, producing conidiospores that are similar to yeast cells.
Habitat and distribution
Most species are parasitic on members of the corticioid fungi, specifically species of Aleurodiscus and Stereum, with one species on the ascomycetous genus Lophodermium. Those on Aleurodiscus, including Phaeotremella mycophaga, parasitize the fruit bodies of their hosts; those on Stereum, such as Phaeotremella foliacea, P. frondosa, and P. fimbriata, parasitize the host mycelium within the wood.
As a group, Phaeotremella species occur worldwide, though individual species may have a more restricted distribution.
Species and hosts
Only species producing basidiocarps (fruit bodies) are listed. Not all hosts are known.
References
Tremellomycetes
Basidiomycota genera
Taxa described in 1912
Yeasts | Phaeotremella | [
"Biology"
] | 767 | [
"Yeasts",
"Fungi"
] |
70,195,064 | https://en.wikipedia.org/wiki/Phaeotremella%20frondosa | Phaeotremella frondosa (synonym Tremella frondosa) is a species of fungus in the family Phaeotremellaceae producing brownish, frondose, gelatinous basidiocarps (fruit bodies). It is widespread in north temperate regions, and is parasitic on other species of fungi (Stereum spp.) that grow on dead attached and recently fallen branches of broadleaf trees.
Taxonomy
Tremella frondosa was first published in 1822 by Swedish mycologist Elias Magnus Fries. The species was not clearly distinguished from Tremella foliacea until molecular research, based on cladistic analysis of DNA sequences, showed that the name Tremella foliacea covered several similar but distinct species. Phaeotremella frondosa is the name adopted for the widespread species growing on broadleaf trees, whilst Phaeotremella foliacea is restricted to conifers.
Phaeotremella pseudofoliacea, first described from England and the type species of the genus Phaeotremella, is considered a synonym of Phaeotremella frondosa. Tremella vasifera, described from Germany, is also considered a synonym.
The epithet "frondosa" means "leafy", with reference to the shape of the fruit bodies.
Description
Fruit bodies are gelatinous, pale to dark brown, up to 7 cm (3 in) across, and seaweed-like (with branched, undulating fronds). Microscopically, the hyphae are clamped and occur in a dense gelatinous matrix. Haustorial cells arise on the hyphae, producing filaments that attach to and penetrate the hyphae of the host. The basidia are tremelloid (globose to ellipsoid, with oblique to vertical septa), 13 to 18 by 12 to 16 μm, usually unstalked. The basidiospores are subglobose to broadly ellipsoid, smooth, 6.5 to 10.5 by 5 to 9 μm, and germinate by hyphal tube or by yeast cells.
Similar species
Phaeotremella foliacea parasitizes Stereum sanguinolentum on conifers. Phaeotremella fimbriata is a European species parasitizing Stereum rugosum on broadleaf trees. Its fruitbodies are comparatively small and dark brown to black. Phaeotremella eugeniae is its temperate Asian counterpart.
Exidia crenata is somewhat similar.
Habitat and distribution
Phaeotremella frondosa is a parasite of Stereum species, including S. hirsutum and S. rugosum, growing on the host's hyphae in the wood rather than on the host's fruit bodies. Following its hosts, fruit bodies of P. frondosa are typically found on dead, attached or recently fallen branches of broadleaf trees.
The species is known from North America, Europe, and northern Asia.
References
External links
Mushroom Expert – photos and description
Tremellomycetes
Fungi described in 1822
Taxa named by Elias Magnus Fries
Fungi of Asia
Fungi of Europe
Fungi of North America
Fungus species | Phaeotremella frondosa | [
"Biology"
] | 675 | [
"Fungi",
"Fungus species"
] |
70,195,077 | https://en.wikipedia.org/wiki/Phaeotremella%20foliacea | Phaeotremella foliacea (synonym Tremella foliacea) is a species of fungus in the family Phaeotremellaceae. It produces brownish, frondose, gelatinous basidiocarps (fruit bodies) and is parasitic on the mycelium of Stereum sanguinolentum, a fungus that grows on dead attached and recently fallen branches of conifers. It is widespread in north temperate regions. In the UK it has the recommended English name leafy brain and has also been called jelly leaf and brown witch's butter. Prior to 2017, the name Tremella foliacea was also applied to similar-looking species on broadleaf trees, now distinguished as Phaeotremella frondosa and Phaeotremella fimbriata.
Taxonomy
Tremella foliacea was first published in 1800 by South African-born mycologist Christiaan Hendrik Persoon. The name remained in use until molecular research, based on cladistic analysis of DNA sequences, showed that Tremella foliacea was not closely related to the type species of Tremella but belonged in a separate genus, Phaeotremella. Further research revealed that the name Tremella foliacea covered several similar but distinct species, the name Phaeotremella foliacea being restricted to the fungus growing on conifers.
The epithet "foliacea" means "leafy", with reference to the shape of the fruit bodies.
Herman Phaff and L. do Carmo Sousa described the yeast Cryptococcus skinneri in 1962 from the frass of the beetle Scolytus tsugae feeding on Western Hemlock (Tsuga heterophylla). DNA sequencing has shown that this is the yeast state of Phaeotremella foliacea.
Description
Fruit bodies are gelatinous, brown to dark brown, up to 5 cm (2 in) across, and seaweed-like (with branched, undulating fronds). Microscopically, the hyphae are clamped and occur in a dense gelatinous matrix. Haustorial cells arise on the hyphae, producing filaments that attach to and penetrate the hyphae of the host. The basidia are tremelloid (globose to ellipsoid, with oblique to vertical septa), 12 to 18 by 10 to 14 μm, usually unstalked. The basidiospores are mostly ellipsoid, smooth, 5.5 to 9.5 by 4.5 to 8.5 μm, and germinate by hyphal tube or by yeast cells.
Similar species
Phaeotremella frondosa is a common and widespread species parasitizing Stereum species on broadleaf trees. It often produces larger and paler fruit bodies than Phaeotremella foliacea. Phaeotremella fimbriata is a European species parasitizing Stereum rugosum on broadleaf trees. Its fruitbodies are comparatively small and dark brown to black. Phaeotremella eugeniae is its temperate Asian counterpart.
Habitat and distribution
Phaeotremella foliacea is a parasite of Stereum sanguinolentum, growing on the host's hyphae in the wood rather than on the host's fruit bodies. Following its hosts, fruit bodies of P. foliacea are typically found on dead, attached or recently fallen branches of conifers.
The species is known from North America, Europe, and northern Asia.
References
External links
Tremellomycetes
Fungi described in 1800
Fungi of Asia
Fungi of Europe
Fungi of North America
Taxa named by Christiaan Hendrik Persoon
Yeasts | Phaeotremella foliacea | [
"Biology"
] | 789 | [
"Yeasts",
"Fungi"
] |
70,195,136 | https://en.wikipedia.org/wiki/Ectopic%20hormone | An ectopic hormone is a hormone produced by tumors derived from tissue that is not typically associated with its production.
On the other hand, the term entopic is used to refer to hormones produced by tissue in tumors that are normally engaged in the production of that hormone.
The excess hormone secretion is considered detrimental to the normal body homeostasis. This hormone production typically results in a set of signs and symptoms that are called a paraneoplastic syndrome.
Some clinical syndromes caused by ectopic hormone production include:
References
Physiology
Endocrinology
Cell signaling | Ectopic hormone | [
"Biology"
] | 116 | [
"Physiology"
] |
70,195,237 | https://en.wikipedia.org/wiki/Cystofilobasidium | Cystofilobasidium is a genus of fungi in the family Cystofilobasidiaceae. Species occur as yeasts, but produce filamentous sexual states that form dikaryote teliospores, from which the unicellular basidia (if present) are formed. The hyphae usually have dolipore septa without a parenthesome, and their cell walls contain xylose. The genus currently contains nine species worldwide.
References
Tremellomycetes
Taxa named by Franz Oberwinkler
Taxa described in 1983
Basidiomycota genera
Yeasts | Cystofilobasidium | [
"Biology"
] | 125 | [
"Yeasts",
"Fungi"
] |
70,195,327 | https://en.wikipedia.org/wiki/Naematelia%20aurantia | Naematelia aurantia (synonym Tremella aurantia) is a species of fungus producing yellow, frondose, gelatinous basidiocarps (fruit bodies). It is widespread in north temperate regions and is parasitic on another species of fungus (Stereum hirsutum) that grows on dead attached and recently fallen branches of broadleaf trees. It is commonly called golden ear in North America.
Taxonomy
Tremella aurantia was first published in 1822 by German-American mycologist Lewis David de Schweinitz, based on collections from North Carolina. In 1921, the species was transferred to Naematelia by Edward Angus Burt, but remained better known as Tremella aurantia until
molecular research, based on cladistic analysis of DNA sequences, showed that Naematelia was a distinct genus.
The epithet aurantia means "golden".
Description
Fruit bodies are gelatinous, bright yellow, up to 15 cm (6 in) across, and lobed to frondose (like seaweed). Microscopically, the hyphae are clamped and occur within a dense gelatinous matrix. Haustorial cells arise on the hyphae, producing filaments that attach to and penetrate the unclamped hyphae of the host. The basidia are tremelloid (spherical to ellipsoid, with oblique to vertical septa), 13–14 by 9–13 μm, sometimes stalked. The basidiospores are subglobose to ellipsoid, smooth, 5.5–9.5 by 4.5–7.5 μm, and germinate by hyphal tube or by yeast cells.
Similar species
Naematelia aurantialba is a very similar species cultivated for food and medicine in China. It was only described in 1990 and differs largely in microscopic details. Tremella mesenterica is a widespread, north temperate fungus that also has bright yellow, gelatinous fruit bodies, but parasitizes the mycelium of Peniophora species, often on dead attached twigs. It too can be distinguished by microscopy, with N. aurantia having smaller spores and basidia.
Macroscopically, Dacrymyces chrysospermus is nearly identical to N. aurantia, but belongs to the class Dacrymycetes and can be distinguished by its growth on conifer and its differently shaped spores and basidia.
Habitat and distribution
Naematelia aurantia is a parasite of Stereum hirsutum, growing on and often completely enveloping host basidiocarps. Following its host, fruit bodies are typically found on dead, attached or recently fallen branches of broadleaf trees.
The species has a mainly north temperate distribution and is known throughout North and South America, Europe, and northern Asia.
References
Tremellomycetes
Fungi of Asia
Fungi of Europe
Fungi of North America
Fungi of South America
Fungi described in 1822
Taxa named by Lewis David de Schweinitz
Fungus species | Naematelia aurantia | [
"Biology"
] | 634 | [
"Fungi",
"Fungus species"
] |
70,195,352 | https://en.wikipedia.org/wiki/Naematelia%20encephala | Naematelia encephala (synonym Tremella encephala) is a species of fungus producing pink, brain-like, gelatinous basidiocarps (fruit bodies). It is widespread in north temperate regions and is parasitic on another species of fungus (Stereum sanguinolentum) that grows on dead attached and recently fallen branches of conifers. In the UK, its recommended English name is conifer brain.
Taxonomy
Tremella encephala was first published in 1801 by Dutch mycologist Christiaan Hendrik Persoon, based on an earlier description by Carl Ludwig Willdenow who had described the species from Germany as Tremella encephaliformis. In 1818, it was selected by Elias Magnus Fries as the type species of Naematelia, a new genus proposed by Fries to accommodate fungi having gelatinous basidiocarps with a hard or compact core. It was not until 1961 that this central core was shown by American mycologist Robert Bandoni to be the remains of the host fungus, Stereum sanguinolentum.
The epithet encephala means "brain", with reference to the shape and colour of the basidiocarps.
Description
Fruit bodies are gelatinous, dull pale pink to yellowish pink, up to 3 cm (1 in) across, and brain-like (compact and densely folded) with a hard, whitish core when cut. Microscopically, the hyphae are clamped and occur within a dense gelatinous matrix. Haustorial cells arise on the hyphae, producing filaments that attach to and penetrate the unclamped hyphae of the host (abundant in the central core). The basidia are tremelloid (spherical to ellipsoid, with oblique to vertical septa), 13–20 by 12–17 μm, usually unstalked. The basidiospores are mostly subglobose, smooth, 6–11 by 5.5–9 μm, and germinate by hyphal tube or by yeast cells.
Habitat and distribution
Naematelia encephala is a parasite of Stereum sanguinolentum, growing on and often completely enveloping host basidiocarps. Following its host, fruit bodies are typically found on dead, attached or recently fallen branches of conifers.
The species has a north temperate distribution and is known throughout North America, and Northern Eurasia. It has also been recorded from Australia.
References
Tremellomycetes
Fungi described in 1801
Taxa named by Christiaan Hendrik Persoon
Fungi of Asia
Fungi of Australia
Fungi of Europe
Fungi of North America
Fungus species | Naematelia encephala | [
"Biology"
] | 566 | [
"Fungi",
"Fungus species"
] |
70,195,362 | https://en.wikipedia.org/wiki/Naematelia%20aurantialba | Naematelia aurantialba (synonym Tremella aurantialba) is a species of fungus producing yellow, frondose, gelatinous basidiocarps (fruit bodies) parasitic on fruit bodies of another fungus, Stereum hirsutum, on broadleaf trees. In China, where it is called jīn'ěr (金耳; literally "golden ear"), it is cultivated for both food and medical purposes.
References
External links
Tremella aurantialba page (Chinese)
Tremella aurantialba page (Chinese)
Tremella aurantialba page (Chinese)
Tremellomycetes
Fungi of Asia
Chinese edible mushrooms
Fungi in cultivation
Fungi described in 1990
Fungus species
Taxa named by Mu Zang | Naematelia aurantialba | [
"Biology"
] | 153 | [
"Fungi",
"Fungus species"
] |
70,196,516 | https://en.wikipedia.org/wiki/Fertility%20fraud | Fertility fraud is the failure on the part of a fertility doctor to obtain consent from a patient before inseminating her with his own sperm. This normally occurs in the context of people using assisted reproductive technology (ART) to address fertility issues.
The term is also used in cases where donor eggs are used without consent and more broadly, in instances where doctors and other medical professionals exploit opportunities that arise when people use assisted reproductive technology to address fertility issues. This may give rise to a number of different types of fraud involving insurance, unnecessary procedures, theft of eggs, and other issues related to fertility treatment.
Types
The main sense of fertility fraud is non-consensual insemination of a patient by her doctor, but there are other types as well.
Egg theft
The first "test tube baby" was facilitated by Robert Edwards in 1978, and he allegedly used eggs without the consent of the women involved.
One of the earliest cases involving egg theft occurred in 1987 in Garden Grove, California, in a clinic run by doctor Ricardo Asch, and his partners doctors Sergio Stone and Jose Balmaceda. Asch took eggs from women undergoing diagnostic procedures and used them in fertility procedures in other women.
Asch and his two partners were accused of taking eggs and embryos from patients without their consent, using them to cause pregnancies in other women, and defrauding insurance companies. The eggs of at least 20 women were used, and at least fifteen live births resulted. Thirty-five patients filed legal actions against Asch. An estimated 67 women were victims of egg or embryo theft. Asch and Balmaceda left the country and avoided trial. Stone faced trial in the case and was sentenced to three years probation for mail fraud. He was fined $50,000 by the judge in the case, required to repay more than $14,000 in restitution to insurance companies, and had to wear an electronic monitoring device.
In the "Egg Affair" in Israel in 2000, police investigated two doctors who were accused of intentionally creating extra eggs in patients needing fertility procedures, and then without their patients' knowledge harvesting and selling the eggs to other fertility patients.
In Italy in 2016, famed Italian gynecologist Severino Antinori, known as the "grandmothers' obstetrician" because of his reputation for helping women over 60 to bear children, was arrested on suspicion of stealing eggs by removing them from a patient's ovaries without her consent under the guise of performing a procedure on her to remove an ovarian cyst. Antinori had recently hired a Spanish nurse at his clinic, and then diagnosed her with an ovarian cyst for the sole purpose of harvesting her eggs without her knowledge. Antinori was arrested at a Rome airport, charged with aggravated robbery and causing personal injury, and placed under house arrest.
Insemination fraud
There have been numerous cases of a healthcare provider fraudulently substituting their own sperm for donor sperm, resulting in pregnancy and birth.
Quincy Fortier, a fertility specialist in Las Vegas, Nevada, in the early 1960s, impregnated female patients with his own sperm leading to 26 children during his 40-year practice. He died in 2006, aged 94 and the story was uncovered only in 2018 when a woman used a home DNA test to celebrate her retirement. The HBO documentary Baby God aired in 2020 was based on the story of Fortier and his decades-long fertility fraud scheme.
Cecil Jacobson, a fertility doctor in the 1980s in Virginia, was originally found to be the biological father of at least seven of his patients' children, including one patient who was supposed to have been inseminated with sperm provided by her husband. DNA tests have since linked Jacobson to at least 15 such children, and it has been suspected that he fathered as many as 75 children by impregnating patients with his own sperm.
In 2018, a woman in Washington State filed suit in U.S. District Court in Idaho against Gerald Mortimer, who was her mother's fertility doctor when her parents resided in Idaho Falls. After having difficulty becoming pregnant, her mother sought help from Mortimer and eventually became pregnant in 1980. The connection to Mortimer was hidden for 37 years until it was finally revealed when the now adult daughter used a DNA kit which returned the connection to Mortimer as her biological father, who had used his own sperm rather than an anonymous donor as agreed.
Donald Cline used his own sperm in his fertility practice in Indianapolis between 1974 and 1987 to covertly father at least 94 offspring. This came to light in 2014, when home DNA test kits were proliferating, and led to the discovery of Cline having used his own sperm to fertilize his patients' eggs. Because there was no law concerning the practice in Indiana, he was charged with obstruction of justice, false advertising, and immoral conduct, and lost his license to practice medicine. Cline pleaded guilty to two Level 6 felony counts of obstruction of justice and received a one-year suspended sentence. The first law in the United States came into effect in 2019 in the state of Indiana as a result of this case. As of May 2022, Cline has paid over $1.35 million to settle three lawsuits, with three more pending. Similar cases were found in other states.
John Boyd Coates III, a Vermont fertility doctor, has had two lawsuits filed against him and has been charged with using his own sperm in cases going back 40 years. His license has since been revoked and a $5.25 million judgment in damages was awarded to the first plaintiff.
Jos Beek, a gynecologist in the Netherlands, conceived 21 children and potentially dozens more using his own sperm after prospective parents turned to him for fertility treatment, an investigation has discovered. He worked at Elisabeth hospital in Leiderdorp, now part of Alrijne hospital, between 1973 and 1998. He died in 2019.
In September 2020, a San Diego woman sued Dr. Phillip M. Milgram for having used his own sperm to inseminate her three decades earlier, instead of anonymous donor sperm. The deception was discovered when her adult son found that Milgram was his biological father after using a home DNA test kit from 23andMe.
In November 2020, a northern California woman sued her former fertility doctor Michael Kiken for having falsely inseminated her with his own sperm forty years prior. She bore two children, but only learned in 2019 from a DNA test kit that her daughter had received as a gift showed that her former fertility doctor is her children's biological father. In addition, her children may have inherited a genetic disease passed on by Kiken.
Jan Karbaat, a fertility doctor in the Netherlands, fathered 90 confirmed children and may have as many as 200 children. He died in 2017.
In 2021, Norman Barwin, an Ottawa fertility doctor, paid out a settlement of $13.375 million to his seventeen children conceived in his clinic in Canada in the 1980s. A total of 244 former patients and their children, including the seventeen conceived using his own sperm, are among the claimants.
In April 2022, a Colorado jury awarded $8.75 million to the families of a dozen women who became pregnant while being treated for infertility using artificial insemination techniques by doctor Paul Brennan Jones of Grand Junction who used his own sperm while the women were his patients in the 1980s. The jury found Jones liable for negligence, fraud, and other claims.
Fertility doctor Burton Caldwell created at least 22 children using his own sperm. Two of his offspring, both the result of insemination fraud, dated in high school, which is the first verified case of accidental half-siblings incest occurring as a consequence of insemination fraud. It has long been theorized that a large number of people with unrecognized very close genetic relationships living in the same community could result in accidental incest.
Other
There are many other types of fertility fraud, and they may take place at various stages of the process:
Competing for patients via misleading information about success rates, either in advertising or during personal interviews
Performing an assisted reproductive technology procedure not covered by insurance, and then billing for a different procedure
Performing unnecessary or futile procedures on patients who are misinformed or poorly informed
False claims of pregnancy, followed by assertions of fetal death
Misuse of sperm, eggs, and embryos, in particular, a health care person substituting their own sperm for donor sperm
Inadequate screening of donors
Embezzlement from sperm banks, theft of human eggs ("egg-snatching") or embryos, or use of eggs without consent
Legal status
Hundreds of children have been fathered by non-consensual insemination worldwide by their physicians, including in the United States, Canada, and the Netherlands, but without specific laws outlawing it, the legal consequences are unclear. Sometimes other laws related to fertility fraud are used against the physician, such as mail, travel, or wire fraud, while others face civil suits. Some physicians have faced ethics charges by the governing bodies of their profession and lost their license to practice medicine.
United States
In the United States, medical students in the 1960s and 1970s donated sperm, and later while trying to develop their practice as a physician, may have gone on to use their own sperm in order to establish a track record of success. There were no laws on the books at the time prohibiting such activity.
Activists have pushed for legislation that would make fertility fraud a crime, and as of February 2022, seven U.S. states have passed laws, and seven others were considering it.
Scope
In the United States, over fifty fertility doctors have been accused of fraud in connection with donating sperm according to a February 2022 news report.
Media adaptations
In 2020, Somethin' Else and Sony Music Entertainment released a podcast telling the story of Jan Karbaat and his children called "The Immaculate Deception".
In 2020, HBO released the documentary Baby God chronicling the life of Quincy Fortier.
In 2021, The Dutch three-part miniseries Seeds of Deceit tells the story of Dutch fertility doctor Jan Karbaat, who inseminated his patients with his own sperm.
In 2022, Netflix released the documentary Our Father by Jason Blum in the true crime genre about the Donald Cline case in the 1970s and 1980s, to mixed reviews.
See also
References
Works cited
Further reading
External links
Centers for Disease Control and Prevention (CDC), Assisted Reproductive Technology
Assisted reproductive technology
Applied genetics
Biotechnology
Bioethics
Fertility medicine
Genetic engineering
Human reproduction
Medical crime
Medical ethics
Obstetrical procedures
Reproductive rights
Health fraud | Fertility fraud | [
"Chemistry",
"Technology",
"Engineering",
"Biology"
] | 2,157 | [
"Bioethics",
"Biological engineering",
"Genetic engineering",
"Biotechnology",
"nan",
"Ethics of science and technology",
"Medical technology",
"Assisted reproductive technology",
"Molecular biology"
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70,196,876 | https://en.wikipedia.org/wiki/Gromia%20dubia | Gromia dubia is a species of testate rhizarian animal in the family Gromiidae. It is known from a single specimen discovered in 1884 by Gruber, and no other specimens have been found. Gruber did not actually make a proper description of the species itself.
See also
Gromia
Testate amoeba
References
Amoeboids
Rhizaria species
Protists described in 1884 | Gromia dubia | [
"Biology"
] | 87 | [
"Individual organisms",
"Species known from a single specimen"
] |
70,197,321 | https://en.wikipedia.org/wiki/NcRNA%20therapy | A majority of the human genome is made up of non-protein coding DNA. It infers that such sequences are not commonly employed to encode for a protein. However, even though these regions do not code for protein, they have other functions and carry necessary regulatory information.They can be classified based on the size of the ncRNA. Small noncoding RNA is usually categorized as being under 200 bp in length, whereas long noncoding RNA is greater than 200bp. In addition, they can be categorized by their function within the cell; Infrastructural and Regulatory ncRNAs. Infrastructural ncRNAs seem to have a housekeeping role in translation and splicing and include species such as rRNA, tRNA, snRNA.Regulatory ncRNAs are involved in the modification of other RNAs.
RNA Classification
Long non-coding RNA
Long non-coding RNA (LncRNA) are a type of RNA which is usually defined as transcripts which are greater than 200 base-pairs in length and not translated into proteins. This limitation distinguishes lncRNA from small non-coding RNAs which encompasses microRNAs (miRNAs), small interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), and other short RNAs. Long non-coding RNAs include lincRNAs, intronic ncRNAs, circular and linear ncRNA.
Long intergenic Non-coding RNA
Long intergenic Non-coding RNA (LincRNA) is defined as RNA transcripts that are longer than 200 nucleotides. These RNAs must not have open reading frames that encode proteins. The term “intergenic” refers to the identification of these transcripts from regions of the genome that do not contain protein-encoding genes. LncRNAs also contain promoter - or enhancer-associated RNAs that are gene proximal and can be either in the sense or antisense orientation.
Circular RNA
Circular RNA (CircRNA) are a novel class of endogenous noncoding RNAs and are characterized by their covalently closed loop structures. This class of ncRNA does not have a 5’ cap or 3’ Poly A tail. It has been hypothesized that cirRNAs may function as potential molecular markers for disease diagnosis and treatment and play an important role in the initiation and progression of human diseases.
Small non-coding RNA
Small non-coding RNA (sncRNA) are a type of RNA. which is usually defined as transcripts which are lesser than 200 base-pairs in length and not translated into proteins. This limitation distinguishes sncRNA from lncRNA. This class includes but is not limited to microRNAs (miRNAs), small interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), and other short RNAs.
microRNA
microRNA (miRNA) plays an important role in regulating gene expression. Majority of miRNAs are transcribed from DNA sequences into primary miRNAs. These primary miRNAs are further processed into precursor miRNAs, and finally into mature miRNAs. The miRNAs in most cases interact with the 3’ UTR region of target to induce mRNA degradation and translational repression. Interactions of miRNAs with other regions, including the 5’ UTR, coding sequence, and gene promoters have also been reported. Under certain conditions, miRNAs are also able to activate translation or regulate transcription, but this is dependent on factors such as location of the effect. This process of interaction is very dynamic and dependent on multiple factors.
Ribosomal RNA
Ribosomal RNA (rRNA) includes non-coding RNAs that play essential roles in rRNA regulation. Ribosomal RNA (rRNA) takes part in protein synthesis. Occasional RNA molecules act catalytically, as RNA enzymes (ribozymes) or take part in protein export. The most important ribozyme is the major rRNA of the large subunit of the ribosome (28s rRNA in eukaryotes). It is now accepted that 28S rRNA catalyzes the critical step in polypeptide synthesis in addition to playing a major structural role.
Small nuclear RNA and small nucleolar RNA
Small nuclear RNA (snRNA) and small nucleolar RNA (snoRNA) are widely known to guide the nucleotide modifications and processing of rRNA. Both snRNA and snoRNA are categorized into a class of small RNA molecules that are present in the nucleus. However, they vary a lot by function. snRNA are 80-350nucletides long while snoRNA are 80-1000 nucleotides long in yeast. snRNA plays a critical role in regulating the pre-mRNA silencing. On the other hand, snoRNAs are involved in mRNA editing, modification of the rRNA and tRNA, and genome imprinting. Major function of snoRNA includes the maturation of rRNA during ribosomal formation. Small nuclear and small nucleolar RNAs are critical components of snRNPs and snoRNPs and play an essential role in the maturation of, respectively, mRNAs and rRNAs within the nucleus of eukaryotic cells. Both snRNA and snoRNA are involved in modifying RNA just after transcription. snRNA can be found in splicing speckles and Cajal bodies of the nucleus of the cell.snRNA and snoRNA requires a phosphorylated adaptor for nuclear export (PHAX) to get transported to the site of action within the nucleus.
Transfer RNA
Transfer RNA (tRNA) helps decode a messenger RNA sequence into a protein. They function at specific sites within the ribosome during translation (the process going from code to protein). Within the mRNA molecule we have three nucleotides in length codons. These codons all have a unique universal code which represents a particular amino acid. tRNAs can be classified as an adaptor molecule, being typically 76 to 90 nucleotides in length.
History
Non-coding RNA
DNA purification in 1869 by Dr. Friedrich Miescher’s, from salmon sperm and pus cells guided the scientists towards the presence of additional molecules in the cell except for proteins. Miescher identified the presence of a highly acidic molecule that he isolated from the pus cells and labeled it “nuclein”. The term was coined as the DNA isolated by Miescher was not protein and was derived from the nucleus of the cell. It wasn’t until 1944, when Oswald Avery proposed the DNA as a genetic carrier of information that the Miescher discovery was brought back to light.
Following the X-ray crystallography, by Rosalind Franklin and the determination of DNA double helix by Watson and Crick in 1953, further enhanced the understanding of DNA structure and allowed for the establishment of central dogma of molecular biology. However, one of the flaws with central dogma was the postulation that information flow proceeds from DNA to RNA to protein, which hinders the understanding of different regulatory mechanisms.
In 1955, George Palade identified the first ncRNA as a part of the large ribonucleoprotein complex (RNP). The second class of ncRNA to be discovered was transfer RNA (tRNA) in 1957. However, the first regulatory ncRNA was a microRNA discovered in 1988 from E.coli and was labeled as micF. On other hand, the first eukaryotic microRNA was discovered in C.elegans in 1993. It was derived from gene lin-4 and was identified as a small RNA molecule (as compared to longer mRNA molecules) forming stem-loop structures. This structure gets further modified to generate a shorter RNA that is complementary to the 3’UTR region of lin-14 transcript. This pathway allowed for a better understanding of different post translational gene silencing pathways. Since then, many other miRNAs have been discovered.
Detailed understanding of the mechanism behind this post translational silencing pathway was established in 2001 by Thomas Tuschl. It was discovered that the double stranded RNA gets processed into a shorter 25 nucleotides long fragment which is then modified into a short hairpin like structure by Drosha complex. The molecule is then diced by dicer enzymes into a functional double stranded RNA (dsRNA). These are then loaded onto the RISC complex which then finds and cleaves the targeted mRNA of interest in the cytoplasm.
It wasn’t until 1989 that the imprinting genes were discovered and the genome imprinting was established. The first two genomic imprinting genes were paternally expressed Igf2r and H19. These were both discovered independently in mice and were localized to chromosome 7. H19 is peculiar as it functions as a lncRNA but undergoes modifications similar to that of pre-mRNA processing such as splicing, 3’ polyadenylation and is transcribed by RNA polymerase II. This lncRNA plays a significant role in mice embryonic development and can be lethal if expressed during prenatal stages. More lncRNAs have been discovered in eukaryotes overtime. One such discovery that allowed for better understanding between H19 functions was a lncRNA called XIST (X inactive-specific transcript).
ncRNA drugs and therapy
The first ncRNA therapeutic drug approved by food and drug administration (FDA) (1998) and the European medicine agency (EMA) (1999) is called Fomivirsen or Vitravene. The target organ is the eye and works against the cytomegalovirus (CMV) retinitis in immunocompromised patients. The drug functions as an antisense oligonucleotide and binds to the complementary sequence of the mRNA that inhibits the replication of human cytomegalovirus. This therapy can also be categorized as Antisense oligonucleotide (ASO) therapy.
There have been many ASO RNA therapeutics that have been approved by FDA and/or EMA over the years, but it wasn’t until 2018 that the EMA approved the drug called Patisiran/Onpattro. The drug uses ds-siRNA as a mechanism of action and is deemed effective against hereditary transthyretin amyloidosis. The mechanism specifically targets the Transthyretin (TTR) mRNA.
RNA therapeutic targets are not limited to mature mRNA but have been used to target mRNA at different stages of maturation. One such example is Nusinersen (Spinaraza), it functions as an ASO and targets pre-mRNA before splicing that corresponds to Survival of motor neuron 2 gene (SMN 2). This drug therapy was approved by FDA and EMA in 2016 and 2017 respectively.
There are some drugs that have been approved by FDA and not by EMA. This can be seen in the case of an ASO type therapeutics called Eteplirsen (Exondys51) which has been approved by FDA in 2016 but not by EMA. It targets pre-mRNA corresponding to Dystrophin (DMD) and works against Duchenne muscular dystrophy.
There are many additional therapeutics that have been developed and are either in phase I or II of the clinical trials. Current RNA therapeutics in clinical trials range from a variety of target organs and diseases ranging from skin (potential treatment for disease such as keloid) to tumors (squamous cell lung cancer).
To date, for both the FDA and the EMA, ncRNAs are considered as "simple" medical products because of their production by chemical synthesis. When some of them, produced biologically (known as bioengineered ncRNA agents: BERAs), will be put on the market, the status of biological medical products will be applied, which could lead to inconsistencies in the legislation.
Applications
Antisense oligonucleotides
Antisense oligonucleotides (ASOs) are single-stranded DNA molecules with full complementarity to one select target mRNA and may act by blocking protein translation (via steric hindrance), causing mRNA degradation (via RNase H-cleavage) or changing pre-mRNA splicing. These short oligonucleotides have already been approved by the FDA for ten genetic disorders and many are currently in the pipeline to be approved/tested. Using oligonucleotide technology, we are now able to control protein expression via RNA interference, and are able to affect previously defined “undruggable” proteins. Even though this therapy has a lot of promise and potential, it comes with many limitations.
Compared to siRNA and microRNA, ASOs are more versatile in reducing protein expression, they have the ability to also enhance target translation. ASOs can also be customized with ease and accuracy, allowing for the targeting of virtually any mutated gene. This allows for a greater level of application in the field of precision and personalized medicine.
The main challenge of ASO therapies to specific tissues and cellular uptake is what poses a great challenge and limitation. Liposomal delivery is one such way to overcome such issues. Liposomal delivery system comes with its own share of limitations. Serum proteins in the bloodstream destabilize the lipoprotein. This destabilization leads to the depletion of protein and exposing cargo to the unstable environment. This hindrance can be overcome by using PEGs (poly(ethylene glycol) . However, PEGs are not biodegradable causing them to accumulate within the body leading to adverse effects and causing hypersensitivity. In addition, multiple rounds of therapy with PEGs can lead to the formation of PEG antibodies, which can lead to lack of efficiency in preventing the rupture of the liposome that it is attached to.
Using immunoliposomes it has been shown that targeting can be more specific as by using antibody’s specific to the protein of expression in that area, it results in the ASO drug directly impact the target site and nowhere else. Moreover, immunoliposomes are slow to dissociate leading to precise release of the ASO drug which they encapsulate.
LncRNA as a therapeutic approach
Long noncoding RNAs (lncRNAs) are large transcripts (more than 200 nucleotides long) that have similar mechanism of synthesis as that of mRNAs but unlike mRNAs, lncRNAs are not translated to a protein. lncRNA contains interactor elements and structural elements. Interactor elements directly interact with other nucleic acids or proteins while the structural elements indicate the ability of some lncRNAs to form secondary and/or tertiary structures. This ability of the lncRNAs to interact with nucleic acids using its interactor elements and its ability to interact with protein using its secondary structures allows it to function in a more diverse manner than other ncRNAs such as miRNA (microRNA). LncRNA has been established to play a role in gene regulation by influencing the ability of specific regions of the gene to bind to transcriptional elements and different epigenetic modifications. One such example can be seen in the case X inactive specific transcript (XIST). In humans, 46,XX females carry an extra X chromosome (155Mb of DNA) compared to 46,XY males. To overcome this dosage imbalance, one X chromosome is randomly inactivated in human females at around the 2-8 cell stage of embryo development. This inactivation is very stable across cell divisions due to epigenetic contributions both during the initial silencing and the subsequent maintenance of the inactive X chromosome (Xi). This inactivation is carried by the lncRNA, XIST. XIST is produced in cis and inactivates the X-chromosome that it has been generated from. The inactive X chromosome can be observed as a condensed heterochromatin structure called “Barr Body”.
A study in 2013 utilized this ability of XIST as a potential therapeutic approach for treatment of trisomy 21. Trisomy 21 is commonly known as down syndrome and is caused due to presence of an additional copy of chromosome 21. The study was one of its kind as no other studies have been able to incorporate the XIST gene into a chromosome due to its large size. The study incorporated the XIST into one of the chromosomes 21 in the cells gathered from patients with down syndrome. The study was able to observe the inactivation of one of chromosome 21 in the form of a condensed heterochromatin and labeled it as a chromosome 21 barr body. Such experiments have shown to work in cells in the lab setting although no lncRNA based therapeutics are in clinical trials. The implications of such work can bring trisomy 21 and other chromosomal disorders in the realm of consideration for future gene therapy research.
Challenges
One of the major issues that hinders the ncRNA therapy is the stability of the single stranded RNA molecule. RNA is typically single stranded therefore slightly unstable as compared to dsDNA molecules. This however can be overcome by fabricating the single stranded RNA to double stranded RNA(dsRNA). This is quite effective as the dsRNA is more stable at room temperature and has a longer shelf life.
Second major issue is the cell/tissue/organ specific targeting of the RNA molecules. Generally, this is overcome by containing the dsRNA in a lipid nanoparticle and using that as a ligand to bind to a receptor on the surface of the target cell. The lipid particles are taken into the liver cells through their specific receptors and this mechanism seems to be effective at targeting the liver cells/cancer.
Another organ with a relatively easy delivery mechanism is the eye. This requires an invasive technique of directly injecting the ncRNA of interest directly into the eye. These techniques are not only invasive but also don’t ensure if all the cells in the target organ are being targeted by the ncRNA of interest.
Additional issues arise once the RNA molecule enters the cell. One of the issues being the immune system. Our immune system can recognize RNA using the intracellular pathogen associated molecular pattern (PAMP) receptors and extracellular toll-like receptors (TLR). Activation of the receptors leads to a cytokine (IFNy-Interferon gamma) mediated immune response. Common applications to overcome the immune response include second generation chemical modifications. This process includes the introduction of small one at a time chemical modifications to avoid the immune response. However, there are some reports of adverse immune responses in clinical trials employing such modified reagents. There’s no fixed answer to issues with immunogenicity and ncRNA therapy.
Modified adenovirus vectors have been used extensively in many clinical trials as a ncRNA delivery mechanism. In particular, adenovirus vector is considered an efficient delivery system due to its stability within live cells and non-pathogenicity. Even though viral transfections have achieved significant results in basic research, one of the issues is the non-specificity leading to off target transfections. Further research needs to be done to improve the accuracy of viral transfections for future tests and clinical trials.
ASO Guidelines
In December 2021, the FDA came up with a draft guidance for the use of ASO drug products. This draft guidance was directed towards sponsor-investigators who are developing individualized investigational antisense oligonucleotides (ASO) drug products for severely debilitating or life threatening diseases. Severely debilitating corresponds to a disease or condition that causes major irreversible morbidity. However, life-threatening is defined as the disease or condition has a likelihood of death unless the course of treatment leads to an endpoint of survival. Usually individuals that have a severely debilitating life threatening disease don't have any alternative treatment options, and their diseases will be rapidly progressing, leading to an early death and/or devastating or irreversible morbidity within a short time frame without treatment.
Drug development is usually targeted for a large number of individuals, in this case that is not possible because of the specificity of the mechanism of action of the ASO combined with the rarity of the treatment-amenable patient population. Under FDA regulations, a protocol under which an individual ASO product is administered to a human subject must be reviewed and approved by an institutional review board (IRB) before it can be administered to human subjects. When the individual is a child, additional safeguards need to be identified in order to prevent any developmental issues from occurring that may affect the life of the individual. The sponsor-investigator needs to get informed consent from the individual or from the person who is responsible for the individual. The consent needs to include a description of reasonably foreseeable risks or discomforts as part of the use of the ASO drug. The sponsor also needs to get individuals clinical and genetic diagnosis to confirm that the ASO will be beneficial. The analysis may be through gene sequencing, enzymatic analysis, biochemical testing, imaging evaluations. All results need to be included in the application. Also the sponsor needs to include evidence that establishes the role of the gene variant targeted by the ASO drug. The sponsor/investigator need to also provide evidence that the identified gene variant or variants are unique to the individual.
The guidance suggests that the starting dose should be based on available non-clinical data that has been collected from model organisms or in vitro studies and should be in correlation with other ASO drug product dosing information that is available. At the starting dose, pharmacological effects are expected. Furthermore, It is advised that a dosing escalation method be utilized. This includes the step of escalating the dodge from its initial dose based on pharmacodynamic effects and/or trial participants' response to the ASO.
In addition, protocols submitted to the FDA need to have a clear dosing plan and justification for selecting the starting dose, dosing interval, and plan for dose escalation or dose reduction based on clinical pharmacodynamic effects of the drug on the individual. Also all anticipated outcomes should be included in the drug plan when submitted to the FDA. It is extremely important for the investigators to monitor the patient closely during dose escalation. During the escalation period, adequate time should be provided in order to see therapeutic results. It is advised that the investigator not make concurrent changes to the dosing interval along with the dose without justification. The submitted plan should include a de-escalation/discontinuation plan if toxicity is observed. All drug administration needs to take place in an inpatient setting just to get a grasp of the adverse effects the drug may have. Once drug toxicity, beneficiancy and adverse effects are identified, the drug can be administered in an outpatient manner as long as the same concentration of drug is administered.
See also
RNA therapeutics
Messenger RNA
RNA editing
References
RNA
Gene expression
Protein biosynthesis
Molecular genetics
Spliceosome
RNA splicing
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70,197,345 | https://en.wikipedia.org/wiki/Christoph%20Weder | Christoph Weder is the former director of the Adolphe Merkle Institute (AMI) at the University of Fribourg, Switzerland, and a professor of polymer chemistry and materials. He is best known for his work on stimuli-responsive polymers, polymeric materials that change one or more of their properties when exposed to external cues. His research is focused on the development, investigation, and application of functional materials, in particular stimuli-responsive and bio-inspired polymers.
Education and career
Christoph Weder was born on July 30, 1966. He began elementary school in Mülheim a. Main, Germany, in 1972 before moving to Thalwil, Switzerland, in 1974, where he completed elementary and secondary school. He then attended the high school Kantonsschule Enge in Zurich, from which he graduated in 1985. Following in the footsteps of his father, who was also a polymer chemist, Weder studied chemistry at the Swiss Federal Institute of Technology (ETH Zurich) in Zurich, where he received his diploma in chemistry in 1990. He then joined the research group of Professor Ulrich W. Suter as a doctoral student and in 1994 was awarded the degree of Doctor of Natural Sciences for his dissertation “New Polyamides with Stable Nonlinear Optical Properties.” While at ETH, Weder was also trained as a chemistry teacher and received his teaching certification in 1992. With a fellowship from the Swiss National Science Foundation, Weder then spent one year as a postdoctoral research fellow in the Department of Chemistry at the Massachusetts Institute of Technology, where he worked under the guidance of then-provost Mark S. Wrighton.
Weder returned to the Department of Materials of ETH Zurich in 1995, where he joined the group of Professor Paul Smith and continued to work on photofunctional polymers. Based on his habilitation thesis entitled “Polarizing Light with Polymers,” Weder received his habilitation and, bestowed with the venia legendi, became an independent lecturer in 1999. In 2001, Weder left ETH and joined Case Western Reserve University in Cleveland, Ohio, as an associate professor in the Department of Macromolecular Science and Engineering. He was promoted to professor in 2007, and in 2008 was named the F. Alex Nason Professor.
In 2009, Weder returned to Switzerland and joined the Adolphe Merkle Institute (AMI) as Professor of Polymer Chemistry and Materials. AMI, which was founded in 2008 thanks to a gift from Adolphe Merkle, is an interdisciplinary research center that focuses on fundamental and application-oriented research in soft nano- and materials sciences. In January 2010, Weder was appointed as the institute’s director, serving until April 2022.
Weder led a team that was awarded a grant from the Swiss National Science Foundation (SNSF) to establish the National Competence Center in Research (NCCR) Bio-Inspired Materials. He served as the center’s director from its launch in 2014 until 2020. The NCCRs are a research instrument of the Swiss National Science Foundation (SNSF) that aim to strengthen research in areas of strategic importance for the future of Swiss science, business and society.
Weder remains an adjunct professor at CWRU and has served as a visiting professor at Chulalongkorn University in Bangkok, Thailand since 2003. He serves as an Associate Editor of ACS Macro Letters and was a co-editor of the RSC Book Series Polymer Chemistry from 202-2021.
Weder has co-authored more than 300 peer-reviewed articles in scientific journals and over twenty book chapters. He also edited two books. As of March 2022, Weder has an h-index of 87 and his works have been cited more than 27,000 times.
Weder is a co-inventor of more than twenty patent families that protect technologies such as light-polarizing security features, mechanochromic materials, sea-cucumber inspired dynamic mechanical polymer nanocomposites, stimuli-responsive supramolecular polymers, materials for optical upconversion, shape memory polymers, and optical data storage systems. He was a co-founding board member of the ETH-spinoff company Omlidon Technologies, LLC (1999–2002), and served on the board of directors of Gel Instrumente AG (1994–2006).
Weder is the recipient of a 3M Non-Tenured Faculty Award, a DuPont Young Professor Award, an NSF Special Creativity Award, and the Case School of Engineering Award. He was awarded a prestigious European Research Council (ERC) Advanced Grant, and is a Fellow of the American Chemical Society’s Division of Polymer Chemistry. In 2017, he was nominated as a member of the Swiss Academy of Technical Sciences "in recognition of his pioneering work in the development of nanomaterials through combination of fundamental research and practical applications as well as his contribution to the successful establishment of the Adolphe Merkle Institute".
Weder is married and has three children.
Research
Weder’s early research activities in the 1990s focused on polymers with special optical properties. This involved the development of nonlinear optical polymers and investigations of the structure-property relationships of photoluminescent poly(p-phenylene ethynylene)s. He demonstrated the usefulness of these semiconducting polymers as the active layer in polymer-based light-emitting diodes. His group also exploited the possibility to orient such rod-like molecules to create fluorescent materials that display linearly polarized absorption and emission. Such materials formed the basis of security features that Weder’s group developed, which were used as an anti-counterfeiting element in security paper. His team also discovered a light-polarizing energy transfer effect that can be used to produce highly efficient fluorescent polarizers. Such elements are useful in display and other applications.
Weder’s research focus turned to stimuli-responsive polymers shortly after he moved to CWRU in 2001. In 2002, Weder’s research lab developed a novel method to create polymeric materials that change their fluorescence color upon deformation. Recognizing the potential for practical applications this effect had, Weder established a research program to develop polymers that translate mechanical forces into optical signals, which is still active today, and shortly thereafter, mechanochromic polymers began to attract widespread interest. Most of the mechanochrochromic materials reported by Weder’s group in the following two decades operate on the basis of the same general transduction principle, which involves changing the interactions among optically active motifs in response to mechanical deformation. Recent discoveries include the development of new mechanically responsive motifs or “mechanophores” based on rotaxanes and loop-forming dye pairs.
Controlling the interactions between molecular or nanoscale building blocks through an external stimulus has become one of Weder’s main design tools for the creation of stimuli-responsive polymers. In 2008, in collaboration with his colleague Stuart Rowan, Weder introduced stimuli-responsive mechanically adaptive polymer nanocomposites whose architecture and function was inspired by sea cucumbers. The mechanical properties of these materials, which were made by incorporating nanocellulose crystals as a reinforcing filler into polymer matrices, depend on the interactions among the cellulose nanocrystals (CNCs), and can be regulated by an external stimulus. The approach was initially used to create mechanically morphing implant materials, which soften upon exposure to physiological conditions. This work led to sustained research efforts in Weder’s group on bio-inspired mechanically morphing polymers, the development of protocols for the processing of CNC/polymer nanocomposites, and the development of new cellulose-based nanocomposites. Adaptive polymers that show such mechanical morphing upon exposure to physiological conditions were reported to increase the functionality of cortical implants.
The possibility to heal defects in polymeric materials can increase the reliability and durability of polymer products. In 2011, also in collaboration with Rowan, Weder demonstrated that the UV-light induced temporary disassembly of metallosupramolecular polymers can be used to heal defects in these materials. Expanding on this concept, Weder’s team introduced light healable nanocomposites, and modified the structure to include different binding motifs and architectures, for example glassy hydrogen-bonded supramolecular polymer networks. His group also used this approach to develop adhesives with the capability to bond or debond on demand. Weder’s group sought to push the mechanical properties of supramolecular polymers towards those of conventional thermoplastics. In 2019, his team demonstrated that it is possible to toughen stiff but brittle glassy supramolecular polymer networks by forming blends with a rubbery component. More recent versions of such materials were shown to be healable and to display property combinations that are comparable to some conventional plastics.
References
1966 births
Living people
21st-century Swiss chemists
Massachusetts Institute of Technology alumni
20th-century Swiss chemists
Polymer chemistry
Polymer scientists and engineers
ETH Zurich alumni
Christoph Weder | Christoph Weder | [
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70,198,518 | https://en.wikipedia.org/wiki/Reflexive%20control | Reflexive control is control someone has over their opponent's decisions by imposing on them assumptions that change the way they act.
Methods of reflexive control are widely used in a variety of fields: advertising, public relations, military art, etc. An example of such a strategy could be a card shark deliberately losing the first hands in the game, systematic diversionary attacks on an unimportant area of combat, etc..
Introduction
As defined by Soviet scholar Vladimir Lefebvre reflexive control is a process in which one adversary hands over to the other the basis for decision-making. In other words, there is a substitution of motivation factors of the enemy in order to encourage him to take disadvantageous decisions.
Professor G. Smolyan believes that the key point of reflexive control is implicitly forcing a subject to choose a desired result. As an aphoristic example of reflexive manipulation we can recall an episode from "Uncle Remus's Tales" in which Brother Rabbit eludes Brother Fox by asking:
The oldest of those literary villains who specialized in reflexive control is considered to be the biblical serpent who provoked Eve to taste the forbidden fruit. The category of typical provocateurs can also include one of the famous characters of the Swedish writer Astrid Lindgren, who terrorized the housewife Freken Bock with a simple question:
Individual techniques of reflexive control called "stratagems" have occupied an important place in the history of military art since ancient times. For example, Sun Tzu put in the title of the first chapter of one of his treatises the statement "War is the way of deception," thus defining the craft of warfare as the art of deception.
The preconditions for the actual emergence of the theory of reflexive control can be found in the Soviet military literature of the mid-20th century; four main stages are distinguished in the process of its improvement:
from the early 1960s to the late 1970s: research,
late 1970s to early 1990s: practice-oriented,
from the beginning to the middle of the 1990s: psychological and pedagogical,
since the late 1990s: psychosocial.
Among the most authoritative scientists who dealt with the tasks of reflexive control, in addition to V. Lefebvre, the works of D. Pospelov, V. Burkov, V. Lepsky, G. Shchedrovitsky and others are noted. In addition to them, the artistic aspects of the subject of reflexive control were reflected in the works of some major writers, for example, V. Pelevin.
Military application
General provisions
A formally approved terminology of reflexive control did not exist in the military art in the past; nevertheless, its tools were intuitively recognized and were actively used in attempts to calculate the actions of an adversary or to create an erroneous impression of him/herself.
According to some Russian military experts, applied aspects of reflexive control, having geopolitical significance, are an effective tool for conducting information warfare and can have significant advantages over traditional methods of using military means. Exploiting moral stereotypes of behavior, psychological factors, personal information about the command personnel (biographical data, habits, etc.) reflexive control makes it possible to increase the chances of achieving victory, but it is noted that this tactic requires information about the enemy with a high degree of detail and quality.
Among the tools of reflexive control are also listed camouflage (at all levels), disinformation, provocation, blackmail, compromising, etc., whose vector of action is aimed more at the hard to grasp and subjectively perceived elements of "military art" than at the more objective concepts of "military science". Modern computerization can make it difficult to use reflexive control methods because their application is easily revealed by mathematical modeling. Nevertheless, one cannot dismiss the existence of a broad class of exceptions where machine intelligence may lack an intuitive understanding of real reality.
In reviewing Russian research on the use of the arsenal of reflexive control for military purposes, American scholar T. L. Thomas singled out the work of Colonel S. A. Komov as the most productive military theorist in this area. In his publications, Komov made extensive use of developments from the field of reflexive management under the name of "intellectual methods of information warfare," highlighting the following main elements.:
Distraction through a real or perceived threat to one of the enemy's key positions (on the flanks, in the rear, etc.) during preparations for military action,
overloading through supplying the enemy with large volumes of self-contradictory information,
paralysis, creating the illusion of pinpointed threats to vital interests or the most vulnerable locations,
exhaustion, forcing the adversary to expend resources to perform unproductive activities,
deception, provoking the enemy to redeploy forces to the threatened area in preparation for military action,
splitting, forcing the enemy to act against the interests of his allies,
appeasement, by lowering vigilance and creating the illusion that routine training, rather than preparations for offensive actions, are taking place,
intimidation, by creating the appearance of invincible superiority,
provocation, through the imposition of an unfavorable scenario of action,
suggestion, through the presentation of information material that influences legally, morally, ideologically or in other spheres,
pressure, through the presentation of information material that discredits the government in the eyes of the population.
Another domestic researcher who attracted interest abroad was Professor F. Chausov, who formulated the following principles of reflexive management:
principle of purposefulness — the process should be goal-oriented, involving the full range of necessary measures of reflexive management,
principle of actualization - there should be an "updating" of planning, providing a fairly complete picture of the intellectual potential of the command and staff, especially in situations related to the global information space,
principle of conformity - mutual consistency of goals, place, time and methods of reflexive management must be observed,
simulation principle — one should not forget about forecasting and modeling the actions and states of the opposing side during the execution of reflexive control procedures,
principle of anticipation - current events must be anticipated and anticipated.
In addition, when using reflexive management, Chausov gave an assessment of risk, the essence of which boils down to the danger of making a mistake if you misjudge the consequences. With this approach, the maximum risk would be if the adversary unravels the plan himself.
One well-known example of the effective use of the theory of reflexive control was the disinformation work of the Soviet secret services to create an exaggerated impression on the American side of the shock potential of Soviet nuclear weapons. To this end, fake models of intercontinental ballistic missiles were developed for participation in Red Square parades, and their appearance was immediately reflected in the reports of foreign attachés to their superiors. The next stage was to provide indirect evidence of the real existence of these missile systems, which would then divert the resources of foreign developers to unsuccessful attempts to reproduce the allegedly "new" technology.
Similarly, British intelligence conducted disinformation support for the Allied landings in Sicily, codenamed Operation Mincemeat. For this purpose, a dead body dressed as a British serviceman was planted in the sight of the Reich's special services with a set of skilfully fabricated documents describing an alleged British landing operation in the Peloponnese and Sardinia. Judging by these plans, the informational screen for this landing was to be demonstrative preparations for a fake attack on Sicily. The German leadership carried out a set of works to strengthen the Greek coast, redeployed there a tank division, but quite unexpectedly for them the main blow was struck in Sicily.
Many Russian writers believe that another textbook example of reflexive control is the American Strategic Defense Initiative program, which forced the Soviet Union to spend significant resources to develop a similar space system.
According to a number of non-Russian researchers, manipulative methods from the field of reflexive control form the basis of Russia's new concept of military action in the 21st century, which in the West has been called the ".». At the same time, some publications have been critical of the applied aspects of this theory, and it has even been called pseudoscientific.
References
Bibliography
Денисов А. А., Денисова Е. В. Краткий очерк основ теории управляемой конфронтации (рус.) // Информационные войны : журнал. — 2014. — Т. 29, No. 1. — С. 24–33. —
Лепский В. Е. Технологии управления в информационных войнах (от классики к постнеклассике). — Москва: Когито-Центр, 2016. — С. 160. —
Нургалеева Л. В. Проблема рефлексивного управления как аспект современной коммуникативной культуры (рус.) // Вестник Томского государственного университета : журнал. — 2013. — Т. 10, No. 2.
Раскин А. В., Тарасов И. В. Рефлексивное управление как технология информационного воздействия (рус.) // Информационные войны : журнал. — 2014. — Т. 29, No. 2. — С. 15–17. —
Чепиницкая П. Р. Технологии социальной регуляции в рефлексивном управлении российской зарубежной диаспорой (рус.) // Теория и практика общественного развития : журнал. — 2011. — No. 3.
Jainter M., Kantola H. Reflexive Control in Cyber Space (англ.) // Academic Conferences International Limited. — 2016. — Июль. — С. 155–162.
Kasapoglu C. Russia's Renewed Military Thinking: Non-Linear Warfare and Reflexive Control (англ.) // Research Division, NATO Defence College : Research Paper. — 2015. — Ноябрь (No. 121). — С. 1–12. —
Thomas T. Psycho Viruses and Reflexive Control: Russian Theories of Information-Psychological War // Information at War: From China's Three Warfares to NATO's Narratives. — London: Legatum Institute, 2015. — Vol. September. — P. 16–21. — (Beyond Propaganda). —
Mind control
Public relations
Information operations and warfare
Sociology
Control theory
Pages with unreviewed translations | Reflexive control | [
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70,198,588 | https://en.wikipedia.org/wiki/Pneumatode | In botany, pneumatodes are air-containing structures in plant roots. Their function is to allow gaseous exchange in root tissues. This can be beneficial to semi-aquatic plants, such as neo-tropical palms. Plants with photosynthetic roots, such as epiphytic orchids like Dendrophylax lindenii also possess these structures. They play a role in fungal interactions.
Etymology
The name of the structure is derived from the Greek word πνεῦμα (pneûma), meaning breath and ὁδός (hodós), meaning pathway.
Fungal interactions
Fungal infections of plants may begin through penetration of the roots through pneumatodes.
Functional analogy to stomata
Pneumatodes are considered as a special type of cyclocytic stomata. The entire structure may rise above the adjacent epidermis. The pneumatodes may function as double structures for gas exchange and liquid water elimination (guttation). Leafless orchids with photosynthetic roots rely on the gas exchange through pneumatodes for photosynthesis.
Taxonomic importance
These structures are characteristic for different species and can be used to differentiate between them. These features can be used to distinguish between palm species. They can also be used in the field of paleobotany, as the structures may be preserved in fossilized roots.
References
Plant anatomy
Plant physiology
Plant roots | Pneumatode | [
"Biology"
] | 290 | [
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70,199,765 | https://en.wikipedia.org/wiki/Bohemian%20matrices | A Bohemian matrix family is a set of matrices whose entries are members of a fixed, finite, and discrete set, referred to as the "population". The term "Bohemian" was first used to refer to matrices with entries consisting of integers of bounded height, hence the name, derived from the acronym BOunded HEight Matrix of Integers (BOHEMI). The majority of published research on these matrix families studies populations of integers, although this is not strictly true of all possible Bohemian matrices. There is no single family of Bohemian matrices. Instead, a matrix can be said to be Bohemian with respect to a set from which its entries are drawn. Bohemian matrices may possess additional structure. For example, they may be Toeplitz matrices or upper Hessenberg matrices.
Applications
Software testing
Bohemian matrices are used in software testing, particularly in linear algebra applications. They are often distinctly represented on computers and are identifiable for extreme behavior through exhaustive search (for small dimensions), random sampling, or optimization techniques. Steven E. Thornton utilized these concepts to develop a tool that solved over two trillion eigenvalue problems, revealing instances of convergence failure in some popular software systems.
The anymatrix toolbox is an extensible MATLAB matrix tool that provides a set of sorted Bohemian matrices and utilities for property-based queries of the set.
Improved bounds
In a presentation at the 2018 Bohemian Matrices and Applications Workshop, Nick Higham (co-author of the anymatrix toolbox) discussed how he used genetic algorithms on Bohemian matrices with population to refine lower bounds on the maximal growth factor for rook pivoting.
Connections to other fields
Random matrices
Bohemian matrices can be studied through random sampling, a process that intersects with the field of random matrices. However, the study of random matrices has predominantly focused on real symmetric or Hermitian matrices, or matrices with entries drawn from a continuous distribution, such as Gaussian ensembles. Notable exceptions to this focus include the work of Terence Tao and Van Vu.
Bernoulli and Hadamard matrices
The term Bernoulli matrices is sometimes used to describe matrices with entries constrained to , classifying them as Bohemian matrices. A Hadamard matrix is a Bernoulli matrix that satisfies an additional property, namely that its determinant is maximal. Hadamard matrices (and Bernoulli matrices) have been studied for far longer than the term "Bohemian matrix" has existed. The questions posed about Hadamard matrices, such as those concerning maximal determinants, can also be applied to other Bohemian matrices. One generalization of Hadamard matrices includes Butson-type Hadamard matrices, whose entries are th roots of unity for , and can also be considered prototypical Bohemian matrices.
Graph theory
Matrices with discrete entries, particularly incidence matrices, play a crucial role in understanding graph theory. The results from graph theory research can elucidate phenomena observed in Bohemian matrix experiments. Conversely, experiments conducted using Bohemian matrices can provide valuable insights into graph-related problems.
Combinatorics
Several open problems listed in the Encyclopedia of Integer Sequences concerning Bohemian matrices are combinatoric in nature. For instance, A306782 lists a table of the number of distinct minimal polynomials for Bernoulli matrices (Bohemian matrices with entries ) up to dimension 5. The numbers for higher dimensions remain unknown. The number of valid Bernoulli matrices of dimension 6 is ; while this set could be exhaustively searched (it is delightfully parallel), the greater-than-exponential growth of the number of matrices quickly grows beyond the limits of numerical analysis. There are symmetries that might be taken advantage of, as is done for zero-one matrices, but these require sophisticated combinatorics knowledge.
Number theory
Many number theorists have studied polynomials with restricted coefficients. For instance, Littlewood polynomials have coefficients in the monomial basis. Researchers such as Kurt Mahler, Andrew Odlyzko, Bjorn Poonen and Peter Borwein have contributed to this field. By using companion matrices, these polynomial problems with restricted coefficients can be framed as Bohemian matrix problems. However, the characteristic polynomial of a Bohemian matrix may have coefficients that are exponentially large in the matrix dimension, so the reverse transformation is not always applicable.
Connections to Magic Squares are explored in Kathleen Ollerenshaw's book with D. Brée. Furthermore, Bohemian matrices are explicitly connected to quadratic forms in certain papers.
Solution of polynomial equations
To find the roots of a polynomial, one can construct a corresponding companion matrix and solve for its eigenvalues. These eigenvalues correspond to the roots of the original polynomial. This method is commonly used in NumPy's polynomial package and is generally numerically stable, though it may occasionally struggle with polynomials that have large coefficients or are ill-conditioned.
Improving this situation involves finding a minimal height companion matrix for the polynomial within a Bohemian matrix family. However, no efficient general-purpose techniques are currently known for this approach.
History
The term "Bohemian matrices" and the concept of categorizing problems in this manner first appeared in a publication by ISSAC in 2016.<ref
name=thornton></ref> The name originated from the mnemonic BOunded HEight Matrix of Integers (BOHEMI), although the classification has since been expanded to include other discrete populations, such as Gaussian integers. The utility and scope of this categorization are becoming increasingly recognized, with the first significant journal publication following smaller earlier publications. As of March 2022, several publications explicitly use the term "Bohemian matrices," in addition to those already cited in this article.
The inaugural workshop on Bohemian matrices was held in 2018 at the University of Manchester, titled "Bohemian Matrices and Applications." The concept is akin to the specialization suggested by George Pólya, titled "Bohemian Matrices and Applications." The concept is akin to the specialization suggested by Littlewood polynomial.
This concept shares similarities with sign pattern matrices, where two matrices with real entries are deemed equivalent if corresponding entries have the same sign. A Bohemian matrix with the population is an example of a sign pattern matrix and adheres to the defined properties but may also exhibit unique characteristics specific to its Bohemian nature.
References
Matrices | Bohemian matrices | [
"Mathematics"
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"Mathematical objects"
] |
70,200,177 | https://en.wikipedia.org/wiki/Badreddine%20Assouar | Badreddine Assouar (born May 5, 1974) is a physicist, currently director of research at CNRS and the University of Lorraine in France. His research focuses on metamaterials, metasurfaces, phononic crystals and SAW devices.
He is an associate editor of Physical Review Applied.
Career
Badreddine Assouar received his master's degree in 1998, his PhD in 2001 and his Habilitation to Supervise Research in 2007 from the University of Lorraine in France.
After a postdoctoral fellowship, he entered to the French National Center of Scientific Research (CNRS) in 2002.
From 2010 to 2012, he joined the Georgia Institute of Technology in Atlanta as a visiting professor in the international research unit (CNRS – Georgia Tech). In 2020, he became Director of Research at CNRS. He is the founder and the head of the “Metamaterials and Phononics” group at the Institut Jean Lamour (CNRS-University of Lorraine).
Honors and awards
In 2009, he received the first research prize from the Lorraine region.
In 2013, he won the Award of Scientific Excellence from CNRS.
In 2024, he has been elected a Fellow of the European Academy of Sciences (EurASc).
References
1974 births
Living people
University of Lorraine alumni
Academic staff of the University of Lorraine
Research directors of the French National Centre for Scientific Research
Metamaterials scientists
21st-century French physicists | Badreddine Assouar | [
"Materials_science"
] | 295 | [
"Metamaterials scientists",
"Metamaterials"
] |
70,200,873 | https://en.wikipedia.org/wiki/National%20Federation%20of%20Chemicals | The National Federation of Chemicals () was a trade union representing workers in various manufacturing industries in Spain.
The union was founded in 1977, and affiliated to the Workers' Commissions. In 1981, workers in the glass and ceramics industries transferred over from the National Federation of Construction. By the end of the year, it had 19,913 members, and by 1993, its membership had grown to 30,254. That year, it merged with the National Federation of Textiles and Leather, to form the Federation of Textile, Leather, Chemical and Allied Industries.
References
Chemical industry trade unions
Trade unions established in 1977
Trade unions disestablished in 1994
Trade unions in Spain | National Federation of Chemicals | [
"Chemistry"
] | 133 | [
"Chemical industry trade unions"
] |
70,201,270 | https://en.wikipedia.org/wiki/BAT99-7 | BAT99-7 is a WN-type Wolf-Rayet star located in the Large Magellanic Cloud, in the constellation of Dorado, about 160,000 light years away. The star has a spectrum containing extremely broad emission lines, and is the prototype for the "round line" stars, Wolf-Rayet stars whose spectra are characterized by strong and broad emission lines with round line profiles. The broad emission lines hint at an extremely high temperature of nearly , which would make it the hottest of all WN stars with known temperatures, as well as an extraordinarily large mass loss rate for a Wolf-Rayet star in the LMC, at /yr, which means that every 30,200 years, the star loses 1 solar mass worth of mass.
References
Stars in the Large Magellanic Cloud
Wolf–Rayet stars
Dorado
J04553134-6730028
032109 | BAT99-7 | [
"Astronomy"
] | 192 | [
"Dorado",
"Constellations"
] |
70,201,328 | https://en.wikipedia.org/wiki/Maja%20Vukovi%C4%87 | Maja Vuković is a computer scientist, doing research in Artificial intelligence, Blockchain and Cloud Software among others.
She has been appointed an IBM Fellow in 2021 and in IBM she was responsible for technical and research strategy for AI driven Application Modernization.
Education and career
She received her Bachelor of Science with a double major in Computer Science and Mathematics from the University of Auckland, New Zealand, a degree in Computer Science from the International University in Germany in 2000, and a PhD in Computer Science from the University of Cambridge in 2006, for her work on context-aware service composition using AI Planning.
Research interests
Her research interests span different areas, including: AI for Application Modernization; Cloud Transformation, Infrastructure Discovery, Cloud Automation; AI Planning, Machine Learning; Enterprise Crowdsourcing; and Social Web for Disaster Management among others.
Maja is a member of IBM Academy of Technology and an IBM Master Inventor, with over 180 patents granted, including the "Coffee Delivery Drone" patent.
She is a Senior Member of IEEE and a Senior Editor at the ACM Ubiquity journal.
She is a frequent podcaster
and has been interviewed at major conferences.
She is currently involved in an open source community for app modernization.
Awards and honors
Maja was awarded the Women in Services Computing Award by IEEE in 2018.
References
External links
Living people
Artificial intelligence researchers
Computer scientists
Women computer scientists
IBM Women
Alumni of the University of Cambridge
Year of birth missing (living people) | Maja Vuković | [
"Technology"
] | 291 | [
"Computer science",
"Computer scientists"
] |
70,201,444 | https://en.wikipedia.org/wiki/Glass%20instrument | This family of musical instruments (also called crystallophones) includes those whose primary material is glass. They may be played using percussive techniques, such as striking the glass to produce a sound, or by utilizing friction to generate a resonant sound (a playing technique used for friction idiophones). Many glass instruments produce an ethereal, otherworldly timbre. A well-known glass instrument is Ben Franklin's glass harmonica.
History
First glass instruments
Historical records suggest that early versions of glass and porcelain instruments were first developed around the 14th century in China, Japan, and Persia. An encyclopedia of Chinese instruments in 1300 A.D. mentions an instrument consisting of "nine cups, struck with a stick". Similar musical bowls were recorded in Japan, taking the form of a porcelain gong, and in Persia as a set of earthenware water-filled cups which were tapped to produce notes. These percussive instruments spread to Europe in the following centuries, but they may also have developed independently. Records published at Milan in 1492 contain a woodcut depicting playing glasses as part of an experiment, and an inventory of the in Vienna compiled in 1596 includes descriptions of a glasswork instrument with various octaves and semitones. Publications in 1677 describe using a wet finger to create resonant sounds by stroking the rim of eight glasses with various quantities of wine or other liquids, described as "making cheerful wine music". The music produced by different liquids of the glasses was thought to correspond to emotions relating to the four "humours" of the body, and even was attributed to curing various medical conditions such as "thickness of the blood". These descriptions resemble what is now known as the glass harp, an instrument consisting of various wine glasses filled with water to varying amounts and played by running a wet finger along the rim.
Popularization in the 18th century
The earliest instance of a glass instrument being used in concert music was noted in 1732, with records stating that a series of partially-filled wine glasses were tapped with a muffled stick to perform concertos with supporting instrumentation from bass and violins. Instructions on how to construct a glass harp, referred in a text by the French name Verrillon, were included in a 1738 text published from Germany.
The invention of the glass harp is often attributed to Richard Pockrich, an Irish inventor who popularized the instrument in 1741. His invention, which he referred to as an "angelic organ," consisted of large glass bells which he would strike with a muffled stick and may have later played by running a moist finger along their rims. He popularized the instrument by going on tour in England and Ireland and performing famous pieces such as Handel's Water Music. In 1759, both Pockrich and his angelic organ were destroyed in a fire while staying in London. Performances using the glass harp grew in popularity in the following decades, accompanied by publications on instruction, maintenance, and repertoire.
In 1763, Benjamin Franklin applied the principles behind the glass harp to invent his own glass instrument, the glass harmonica. This instrument places the glass bowls horizontally along a rotating axis. The glasses were originally kept wet by a sponge, but later improvements to the invention by other inventors redesigned the instrument so that the bowls rested in a trough of water, ensuring that their surface is always moist and improving tonal quality and ease of play. The player may rotate the bowls using a treadle operated by their foot, and rest their hands along the bowls to produce a ringing sound. Popularized by its ethereal sound, over 100 composers wrote works to feature this instrument.
The glass harmonica grew very popular in Germany, and is attributed to supporting the romanticism movement in the late 18th century. By 1830, however, the popularity of the glass harmonica declined. The glass harp continued to have widespread popularity in England, in part due to its ease of accessibility compared to the glass harmonica.
The glass dulcimer was also performed during this time. Accounts of this instrument, similar in design to a glass harmonica but struck with soft mallets instead of rubbing with ones hands, appear in books and plays around the 1770s. It is possible this is the same instrument as the glasschord, an instrument consisting of glass bars struck by padded hammers which would be activated by a keyboard, similar to a celesta.
The glass flute (or crystal flute) was patented in 1806 in France by Claude Laurent. These crystal flutes grew in popularity and were owned by emperors, kings, and heads of state, including James Madison. Only 185 of Laurent's glass flutes have survived to the modern day.
Post 18th century and modern
While records of glass instruments persist into the 20th century, evidence indicates that their general popularity and performances declined past the 1850s. Nowadays, glass instruments are used in compositions looking to capture an ethereal atmosphere. Some famous examples include using the glass harmonica in the 1982 film Star Trek II: The Wrath of Khan, as well as Marco Beltrami's film scores for The Minus Man (1999) and The Faculty (1998).
The Library of Congress invited the singer Lizzo to play a crystal flute from their collection in September 2022.
Various modern glassblowers, instrumentalists, and performers have invented and utilized contemporary glass instruments. Some examples include:
Glass marimba, utilized by the Brazilian percussion ensemble, Uakti
Verrophone, invented in 1983 by Sascha Reckert
Cristal Baschet, invented in 1952 by the brothers Bernard and François Baschet
Acoustics and functionality
Glass instruments are typically played as either percussion instruments or friction idiophones, with a few exceptions such as the crystal flute and glass violin.
Percussion
When played using percussive techniques, the exposed glass would be struck with a mallet, finger, or hammer to produce a sound. Due to the fragility of glass as a material, the hammers or mallets used are often dampened with cloth or other material to mitigate the risk of fracturing the instruments. The glass may also be rubbed with the mallet to produce sound.
Friction idiophones
Friction idiophones produce sound by being rubbed or scraped with a non-sounding object. In the case of glass instruments, the glass is often rubbed with a moistened finger to gradually draw out a note. In the example of the glass harp, "as the player's finger moves around the rim of the glass, the nodes and antinodes move with it, resulting in a pulsating sound."
List of glass instruments
References
Glass
Crystallophones | Glass instrument | [
"Physics",
"Chemistry"
] | 1,326 | [
"Homogeneous chemical mixtures",
"Amorphous solids",
"Unsolved problems in physics",
"Glass"
] |
70,201,451 | https://en.wikipedia.org/wiki/Durr%20Al%20Najaf | Durr Al Najaf () is a glossy and clear gemstone from the quartz family. The name means "pearl of Najaf" as it can only be sourced from Wadi-al-Salaam () in Najaf, Iraq. The gemstone is found along the west of Najaf close by the Najaf Sea. It stands out among other stones for its unique translucency. The gemstones are collected at very specific times, especially on sunny days after rain which washes the stones and allows the sun to increase their glitter, making them easier for the collectors to find. The collecting locals know the best times to collect the stone as it holds religious value especially among the Shia Muslims.
Upon preparation of the stones to be worn as rings or necklaces, names of religious figures such as the names of Muhammad and his family, or an Āyah from the Quran are usually engraved on the stones by tradition.
Durr Al Najaf can be found in four forms:
White Glossy Durr: also known as Star Durr
Petrol Durr: known as such as it leans towards a bright black color
Hussainy Durr: ranging from translucent to darker red
Abu Shaara Durr: known for thin lines like hair hence its name
While Durr Al Najaf is not commonly imported or exported, it does have a market where collectors sell finished Durr Al Najaf stones to visitors to Islamic religious sites including Najaf, Karbala, and Kadhimiya.
Religious and cultural significance
Durr Al Najaf is a precious gemstone, one of many which hold special significance in Islamic culture. It is considered a sunnah to wear gemstone rings on specific fingers and ways. There are different interpretations relating to the way such rings are to be worn, one Hadith about Muhammad wearing a silver ring on his right hand which he used to put with the stone facing towards his palm. There is another Hadith stating that Muhammad wore his ring "on his small finger on his left hand" as mentioned in Sahih Muslim, a book containing many Hadith referenced often by Muslim scholars. While there are disagreements on which hand such rings are to be worn, there are a few things the interpretation of Hadith states for certain. One is that such rings are to be worn with the stone facing the palm of the hand. Another is not to wear rings on the middle and index fingers, also as mentioned in Sahih Muslim.
Some believe gemstones have mental and physical healing powers and that one should wear different precious gemstones for different purposes such as peace of mind and prevention of illness. However, there is no support for such beliefs in any Hadith.
References
General references
Al-Tibrīzī Ḵaṭīb. Mishkat Al-Masabih. Sh. Muhammad Ashraf, 1981.
Eaton, Charles Le Gai, et al. The Book of Hadith. Book Foundation, 2008.
gemstones | Durr Al Najaf | [
"Physics"
] | 601 | [
"Materials",
"Gemstones",
"Matter"
] |
70,202,612 | https://en.wikipedia.org/wiki/Naganishia%20vishniacii | Naganishia vishniacii is an extremophile fungus originally isolated as a yeast from soil samples in the dry valleys of Antarctica. The species grows at 4 degrees Celsius and below but not at 26 degrees Celsius and above. Visually it is characterized as a cream mass in culture. It is nonfermentative and assimilates glucose, maltose, melezitose, trehalose, and xylose. Molecular research, based on cladistic analysis of DNA sequences, shows that the species does not belong in the Cryptococcaceae.
References
External links
Tremellomycetes
Fungi of Antarctica
Fungus species | Naganishia vishniacii | [
"Biology"
] | 132 | [
"Fungi",
"Fungus species"
] |
70,202,614 | https://en.wikipedia.org/wiki/Rufina%20Alamo | Rufina G. Álamo Matesanz (born 1954) is a Spanish-American polymer scientist known particularly for her research on polyethylene and polypropylene and on sustainable polymers such as polyoxymethylene made from biomass. She is Simon Ostrach Professor of Engineering and distinguished research professor of chemical and biomedical engineering in the Florida A&M University – Florida State University College of Engineering.
Education and career
Alamo was born in 1954 in Segovia. She earned a bachelor's degree in chemistry from the University of Valladolid in 1977, and a master's in 1978, at the same time earning a postgraduate diploma from the Rubber and Plastics Institute of the Spanish National Research Council. She completed her Ph.D. in chemistry in 1981, at the Complutense University of Madrid.
After postdoctoral research with the Spanish National Research Council and then at Florida State University, she began working in industry as a researcher for the Dow Chemical Company in Spain in 1985. In 1988 she returned to Florida State University as a researcher, and in 1995 she obtained a faculty position as associate professor in the FAMU–FSU College of Engineering. She was promoted to full professor in 2003 and named the Simon Ostrach Professor of Engineering and distinguished research professor in 2013.
Recognition
Alamo was named a Fellow of the American Physical Society (APS) in 2012, after a nomination from the APS Division of Polymer Science, "for her use of well-characterized materials and performance of carefully designed experiments to address structure-property relationships in polyolefins".
Selected publications
Alamo's research publications include:
References
External links
Home page
1954 births
Living people
People from Segovia
Spanish chemists
Spanish women chemists
American chemists
American women chemists
Polymer scientists and engineers
University of Valladolid alumni
Complutense University of Madrid alumni
Florida State University faculty
Florida A&M University faculty
Fellows of the American Physical Society | Rufina Alamo | [
"Chemistry",
"Materials_science"
] | 396 | [
"Polymer scientists and engineers",
"Physical chemists",
"Polymer chemistry"
] |
70,202,731 | https://en.wikipedia.org/wiki/Naganishia%20antarctica | Naganishia antarctica is a yeast species that has been isolated from soil in Antarctica.
This species grows best between and , and some strains have been observed to grow above . This temperature range is one of the only things that can distinguish it from N. albida on the DNA level, however, it can be phenotypically differentiated through its ability to utilize different minerals and its overall appearance. When plated the colonies have a slightly mucosoid appearance, with a white to cream coloration. Naganishia antarctica is able to assimilate nitrogen and glucoronate, and some strains can turn a dirty yellow when doing so. When being cultured in liquid media, constant agitation is required. On a microscopic level this yeast is ovoid. Naganishia antarctica has not been seen to sexually reproduce, but when it reproduces asexually it does so through budding. Mature cells that have not recently budded typically are 4.0 μm by 7.5 μm, and they do not appear to produce pseudomycelium. Naganishia antarctica is not able to ferment, but all of its strains use cellobiose, 2-ketogluconate in hemicalcium salt, gluconate at pH 5.8, glucuronate at pH 5.5, maltose, mannitol, melezitose, soluble starch and succinate at pH 5.5 as sole carbon sources. Only certain strains of N. anarctica can use citrate at pH 6.0, D-glucitol, L-arabinose, raffinose and xylose as sole carbon sources. This species does not require vitamins for optimal growth. Naganishia antarctica is able to produce amylose. This species is also able to assimilate L-lysine, nitrate and cadaverine as nitrogen sources.
References
Tremellomycetes
Fungi of Antarctica
Fungi described in 1992
Fungus species | Naganishia antarctica | [
"Biology"
] | 409 | [
"Fungi",
"Fungus species"
] |
70,202,879 | https://en.wikipedia.org/wiki/Gitee | Gitee () is a proprietary online forge that allows software version control using Git and is intended primarily for the hosting of open source software. It is a fork of Gitea and uses a compatible API. It was launched by Shenzhen-based OSChina in 2013. Gitee claims to have more than 10 million repositories and 5 million users.
Gitee was chosen by the Ministry of Industry and Information Technology of the Chinese government to make an "independent, open-source code hosting platform for China."
Censorship
On May 18, 2022, Gitee announced all code will be manually reviewed before public availability. Gitee did not specify a reason for the change, though there was widespread speculation it was ordered by the Chinese government amid increasing online censorship in China.
See also
GitHub
GitLab
Bitbucket
References
External links
2013 software
Git (software)
Version control
Bug and issue tracking software
Computing websites
Collaborative projects
Project hosting websites
Project management software
Free and open-source software | Gitee | [
"Technology",
"Engineering"
] | 202 | [
"Software engineering",
"Software engineering stubs",
"Computing websites",
"Version control"
] |
70,204,750 | https://en.wikipedia.org/wiki/Austin%20D-Series%20engine | The Austin D and K series engines are a straight-six engine made by the British Austin Motor Company between 1939 and 1968. It was developed for the lorry market, but used in a number of automobiles in its later life. It was an overhead valve non-crossflow cylinder head design. Both block and head were made out of cast iron. All engines had a forged four main bearing crankshaft.
The engine was developed under the close watch of Austin chief Leonard Lord. The design was inspired by the Chevrolet Stovebolt engine, which was an inline six-cylinder used by General Motors' British subsidiary Bedford Vehicles. In the late 1930s, Austin decided to get into the 2-3 ton payload lorry market and in a crash development programme based the design on the basic architecture of the Chevrolet engine. Austin's improvements over the Chevrolet design included detachable-shell main and connecting rod bearings and pressurized lubrication. The initial design had an engine displacement of 3460 cc. During the Second World War, Austin increased the bore and stroke to enlarge it to 3995 cc; it produced . The larger engine was put in military trucks beginning in 1940. Both engine sizes were in production after the war. When the carburettor was changed from Zenith to Stromberg, it produced .
Truck engines had K designations and car engines had D designations.
Applications
The engine was first used in the Austin K30 light truck and Austin K2/Y military ambulance 1939. After the war, it continued to power the later Austin Loadstar 1-ton truck and the 4x4 variant K9.
Post war, it went on to power a number of cars such as the Austin Sheerline and Princess luxury vehicles, Jensen Interceptor and Jensen 541. The last car to have it was the 1968 DM4 Vanden Plas Princess Limousine.
There were also four-cylinder engines based on the D-Series six cylinder engine in various capacities using common parts from 2199-2660cc petrol to 2178-2520cc diesel known initially as the 2.2-litre Austin BS1 OHV. They powered cars such as the Austin 16 hp, A70 Hampshire and Hereford, A90 Atlantic, the Austin-Healey 100-4 and the Austin Gipsy, a generation of commercial vans beginning with the Austin K8, as well as some models of the iconic London black taxi such as the Austin FX3 and Austin FX4.
At some point during Michael Edwardes' restructuring of British Leyland, the plant producing the engine was sold off to Standard Motor Products of India where it was used to power a locally-built Standard Atlas based commercial van known as the Standard Twenty and also the Standard 2000 (a rebadged Rover SD1). During the 1980s, this engine was re-imported from India to be used in the refurbished Carbodies version of the Austin FX4 known as the FX4Q.
See also
BMC A-series engine
BMC B-series engine
BMC C-Series engine
References
External links
D-series Engine rebuild story
D-Series engine
Automobile engines
BMC engines | Austin D-Series engine | [
"Technology"
] | 632 | [
"Engines",
"Automobile engines"
] |
53,157,205 | https://en.wikipedia.org/wiki/Materially%20engineered%20artificial%20pollinators | Materially engineered artificial pollinators are experimental radiowave-controlled micro-drones that use ionic liquid gels for artificial pollination without living insects.
The researchers who are developing this technology published their findings in the 9 February issue of the journal Chem and hope that their research will help counter the problems caused by declining honeybee populations, meeting the modern agricultural demands of colonies and benefit farmers.
Early history
In 2007 Eijiro Miyako, chemist at the National Institute of Advanced Industrial Science and Technology (AIST) Nanomaterial Research Institute, worked to make liquids that could be used as electrical conductors. One of his attempts generated a sticky gel, which was at the time considered a failure. After 8 years this gel was found during a lab cleanup. The researchers were astonished that it had not degraded, retaining its viscosity. Svetlana Chechetka, colleague of Miyako, notes that "conventional gels are mainly made of water and can't be used for a long time, so we decided to use this material for research". Inspired by concerns over honeybees and news reports on robotic insects, Miyako decided to investigate whether the gel could be used to pick up pollen. Miyako collected ants from near his institute, placed a droplet of the gel on some of them and let them wander around for a while in a box of tulips. The ants with the gel on them had more pollen than those without. Separate feet experiments with houseflies discovered a different phenomenon: the gel produces a camouflage effect, changing colour in response to various light sources, which could be used to help artificial pollinators avoid predators.
Drone tests
After these early insect successes, Miyako wanted to move on to drones. He settled on a smaller model that could fly around through flower fields the way a bee does, and simulated the bee's hairy skin by using horse hair coated with the gel. The team flew the 4 × 4 cm sized mechanical bees over pink-leaved Japanese lilies (Lilium japonicum), letting them absorb the pollen. The drones were then flown to a second flower, where grains were deposited to artificially pollinate the plants, causing them to begin the process of generating seeds. This did not occur with control drones (without the gel and hair).
Miyako states that "the findings, which will have applications for agriculture and robotics, among others, could lead to the development of artificial pollinators and help counter the problems caused by declining honeybee populations", that they "believe that robotic pollinators could be trained to learn pollination paths using global positioning systems and artificial intelligence" and that the concept demonstrated "should be expandable to other research areas, including chemical composites, agriculture, biomimetic science, and robotics".
See also
RoboBee
Pollinator decline
Technological fix
References
External links
2017 robots
Flying robots
Micro robots
Pollination | Materially engineered artificial pollinators | [
"Materials_science"
] | 594 | [
"Micro robots",
"Microtechnology"
] |
53,157,387 | https://en.wikipedia.org/wiki/Puccinia%20libanotidis | Puccinia libanotidis, common name moon carrot rust, is a species of rust that infects the moon carrot, Seseli libanotis. It is restricted to the same range as its host plant across Eurasia.
Description and life cycle
Puccinia libanotidis can be identified by three of its five spore types, which leave, respectively, rust-brown, cinnamon-like, and black scab-like sori along the plant. The first spore stage, the uredinioid aecial stage, is the most noticeable, and comprises clusters of brown spores that burst through the plant and form an orange-brown sorus. This sorus may stretch across the petiole and undersides of the leaf veins of the host plant, leading to a gall formation. The aeciospores are spiny and usually are 25–35 × 20–25 μm in size. The second stage involves yellowish pycniospores that form structures around the aeciaspores. These are 3.5 × 2.5 μm in size and produce a resin known as "pycnial nectar". By the end of May, the third (and second conspicuous) stage, that of urediniospores, emerges. These spores are cinnamon-tinted and in diameter with relatively thick – 6.5 μm – wall. When examined under a microscope, they closely resemble the aeciaspores.
During August, the lower leaves of an infected plant will turn yellow. The urediniospores spread out, lightly scattered, across the upper surfaces of the leaves and petioles, and teliospores (comprising the third conspicuous stage) appear. The teliospores are dark brown, almost black, and measure 30–50 × 15–25 μm. They are atypically rounded, with a smooth wall, and slightly constricted at the cross wall that divides them into two cells. These spores overwinter and germinate into basidiospores, which will infect new leaves the following year.
Ecology
Puccinia libanotidis usually only infects S. libanotis, though it has been observed on S. campestre as well. Its range is thus limited to that of the host plant, which is widespread across Eurasia. In 2003, appearance of the rust was reported for the first time in Iran. In Great Britain, S. libanotis is confined to two chalky regions in south-east England, and the rust in turn is quite rare. It had been observed twice, once in 1910 and again in 1946, and was then thought extinct, being unofficially Red Listed as extirpated from Britain in 2006. However, three years later, A. Martyn Ainsworth from Kew Gardens re-discovered the rust. The uredinium of P. libanotidis can in turn be parasitised by the fungus Eudarluca caricis.
References
External links
P. libanotidis at the Catalogue of Life
libanotidis
Fungal plant pathogens and diseases
Fungi described in 1901
Fungus species | Puccinia libanotidis | [
"Biology"
] | 655 | [
"Fungi",
"Fungus species"
] |
53,159,659 | https://en.wikipedia.org/wiki/GG%20Tauri | GG Tauri, often abbreviated as GG Tau, is a quintuple star system in the constellation Taurus. At a distance of about 450 light years (140 parsecs) away, it is located within the Taurus-Auriga Star Forming Region. The system comprises three stars orbiting each other in a hierarchical triple system, known as GG Tauri A, and another binary star system more distant from the central system, known as GG Tauri B.
The system is unusual because it contains two distinct circumstellar disks: one surrounding the entirety of GG Tauri A, and another surrounding the brightest star of GG Tauri A. Its large size and close distance make it ideal to study how exoplanets form within multiple star systems.
Properties
GG Tauri consists of five stars, which are T Tauri stars – a class of variable stars that show irregular changes in brightness. These stars are extremely young and more luminous than their main sequence counterparts, because they have not condensed into the normal size yet. The four components of GG Tauri stars are relatively cool K-type or M-type stars, with these spectral types: K7 for GG Tauri Aa, M0.5 for GG Tauri Ab, M5 for GG Tauri Ba, and M7 for GG Tauri Bb; the age of the system is estimated to be 1.5 million years.
A dynamical study of the system found the masses of the four components to be: for GG Tauri Aa, for GG Tauri Ab, for GG Tauri Ba, and for GG Tauri Bb. At , GG Tauri Bb has a substellar mass and is a brown dwarf. Orbital motion has been detected in the central system (Aa and Ab), but not in the outer pair Ba and Bb (as its orbital period is too long).
A preliminary orbit for GG Tauri Aa and Ab has been calculated, but is not very well constrained. The orbit is moderately eccentric; Some studies have determined that their orbit has a semimajor axis of about 34 au and is misaligned to the circumbinary disk by about 25 degrees. However, other studies have found the orbit to be coplanar to the circumbinary disk, with a larger semimajor axis of about 60 au.
Interferometric techniques have been used to observe GG Tauri Ab, the lower-mass component of the central system. GG Tauri Ab was found to be a binary star system comprising two red dwarfs (Ab1 = M2V, Ab2 = M3V), with a separation of about 4.5 AU. Its orbital period is currently estimated to be around 16 years. This would explain why the GG Tauri Ab's spectrum suggests an unusually low-mass star instead of the higher mass that was measured.
Because of interactions with GG Tauri A, the outer pair GG Tauri Ba and Bb are not very stable. The internal orbit of GG Tauri Ba and Bb must be retrograde relative to its whole orbit around GG Tauri A, in order to be stable.
Circumstellar disks
T Tauri stars are usually surrounded by circumstellar disks of gas and dust. These disks coalesce into protoplanets and then into planets.
The subsystem GG Tauri A has a large, circumbinary (technically circumtrinary) disk. Within the disk, GG Tauri Aa also has a disk, and furthermore, at least one of the Ab stars must have a disk as well. The latter is inferred from the presence of a "gap" in the largest disk, detected at the three-o'clock position, at a position angle of about 268°. First seen in 2002, it is interpreted as a shadow because it does not rotate with the disk. Interstellar material blocks the light from part of the disk, causing this shadow. The Aa and Ab rings are coplanar to each other.
The disk around GG Tauri Aa has a mass of about , or about the mass of Jupiter, at a temperature of about 20 to 30 K. GG Tauri Aa appears to have a jet coming out from the poles, as evidenced by forbidden Fe II lines.
Mass is currently accreting from the inner disks into the stars themselves. Because the disks have not been consumed yet, the larger, circumbinary disk must be supplying mass into the smaller disks. Several lines of evidence point to this. Firstly, a search for diatomic hydrogen gas (H2) could be found up to 100 AU away from the center of the system, but significant emission was also detected 30 au away. This emission was detected where a previous survey found gas streaming from the outer disk to the inner disk, so it was assumed that the emission resulted from mass falling from the inner disk to the outer disk. Observations taken in 2014 showed similar results. Secondly, near-infrared polarimetry of the area showed the same structure connecting the inner and outer disks. The stars of GG Tauri A are closer to the ring on the northern side (where the streamer is) than the southern side. Finally, although there is not much gas falling into the inner disks, the accretion rate of gas has been measured to be ~ yr−1 which is at least the rate of accretion from the inner disks to the stars themselves. Therefore, the outer disk provides enough mass to replenish the inner disks.
Possible protoplanets
At the edge of the outer disk, there is a "hot spot" with additional gas, and at a higher temperature of about 40 K. There are also spiral-shaped formations within the disk. At the center of this "hot spot" may be a protoplanet termed GG Tauri Ac, which is still accreting mass. This would explain the higher gas density and temperature, as well as the spiral formations. If it exists, it would likely be about the mass of Neptune or smaller, given that it has not cleared out a gap at its location. Other planets could explain other spiral features within the disk.
Chemistry
The chemistry of circumstellar disks is important for understanding planetary formation. The inner disk, like other protoplanetary disks, is rich in simple molecules containing elements such as carbon and sulfur. In 2018, hydrogen sulfide () was reported, and in 2021, thioxoethenylidene (CCS) was reported to exist within the disk. Both are the first instances of those species known in a protoplanetary disk. The chemical mechanisms related to their formation are not very well understood.
See also
HL Tauri, a T Tauri star with a protoplanetary disk
BD−22 5866, a quadruple star system with relatively low mass
Taurus (Chinese astronomy)
References
Tauri, GG
Taurus (constellation)
T Tauri stars
K-type main-sequence stars
M-type main-sequence stars
Circumstellar disks
5 | GG Tauri | [
"Astronomy"
] | 1,466 | [
"Taurus (constellation)",
"Constellations"
] |
53,160,070 | https://en.wikipedia.org/wiki/Bini%20the%20Bunny | Bini the Bunny is a rabbit, known for a series of videos posted on the internet. Bini refers to two bunnies: Bini the Bunny Senior and his younger brother, Bini Junior. Bini Junior, who is 2 years old as of 2023, has learned various tricks from his older sibling, including how to play basketball. Both brothers are known for their unique and entertaining skills.
Bini Sr. referred to by the media and fans as the only rabbit in the world who can paint, play basketball, play the guitar/piano and comb and style hair.
As of 2017, Bini and his owner, Shai (Asor) Lighter are Guinness Book of World Record holders for the most slam dunks by a rabbit in one minute.
Bini's most popular video with over 20 million views was created in 2016, titled "When Your Bunny is Addicted to Arcade Games". Bini's social pages have more than 1 million followers. Bini was featured in various TV shows including The Tonight Show with Jimmy Fallon, two Netflix originals, and participated in America's Got Talent.
Background
Bini has starred in more than 60 videos where his talents and intelligence are exemplified. He first became recognizable through his 2013 YouTube video "Funny bunny plays basketball -Bini the bunny". In 2016, Bini and his owner Shai moved from Israel to Los Angeles, California.
Bini the Bunny's tricks include playing basketball, painting with acrylic paints on canvas, combing and brushing humans' hair, jumping, dancing and spinning on command. In April 2020, Bini the Bunny learned to play the guitar and shared it in his first ever guitar-playing video, in which he plays Señorita by Shawn Mendes and Camila Cabello.
Media appearances
His tricks have been documented on video on various media outlets, and he has been featured in articles by Huffington Post, AOL, USA Today, Fox News, and Sky News, among others. In 2016, Bini the Bunny was featured on LittleThings.com by Jessica Rothhaar and on German TV Network RTL Germany on the variety show Best Of .
In July 2017, Bini the Bunny and Shai Lighter were featured on the UK Channel E4 Rude Tube show, Season 11, Episode 9
In July 2017, Bini was on US Weekly magazine
In September 2017, Bini was featured on the cover of Guinness World Records: Amazing Animals
Bini the Bunny and Shai Lighter appeared on The Gong Show on ABC on July 26, 2018. The Gong Show starring Mike Myers, and featured celebrity judges: Will Arnett, Alyson Hannigan, and Lil Rel Howery
In 2018, Bini was invited to the Red Carpet Premiere for the Peter Rabbit movie as a "celebrity rabbit".
On September 27, 2018, Bini the Bunny's first short-feature film was released to the world, titled Rabbit Home Alone which features Shai Lighter, and an array of actors as well as Bini. The movie is a parody of 1990 feature film Home Alone.
In 2019, Bini was featured in National Geographic's book - Weird But True! USA.
In June 2019, Bini the Bunny and his owner Shai Lighter were interviewed on Australia's The Morning Show on Channel 7.
In June 2020, Bini was featured in a new National Geographic's book - Pet Records. The book describes Bini's slam-dunks record.
In April 2021, Bini was featured in the Netflix reality show, Pet Stars (Season 1, episodes 3 and 5).
In June 2021, Bini was featured on The Tonight Show with Jimmy Fallon and showed Jimmy his basketball skill.
In July 2021, Bini the Bunny was featured in the book Little Bunny Dreamer.
In July 2021, Bini the Bunny auditioned and passed the first round in America's Got Talent, he performed in front of the celebrity judges- Simon Cowell, Sofía Vergara, Heidi Klum and Howie Mandel (season 16, episode 8).
In November 2021, Bini the Bunny competed and was featured in World Pet Games on Fox - interspecies competitions.
In January 2022, Bini was featured in a documentary show about intelligent animals - The Secret Life Of Our Pets - Episode 2 on ITV channel .
In February 2022, Bini and Shai Asor Lighter were featured in the PEOPLE magazine and TV Show - (FEB 14, 2022 EDITION).
In June 2022, Bini and Shai were featured and interviewed in the Netflix documentary show, The Hidden Lives of Pets (a documentary about extraordinary pets).
Little Bunny Dreamer
In July 2021, Shai Lighter released his kid's book Little Bunny Dreamer, based on the real Bini the Bunny and his talents.
Hoppy Brush
In February 2020, Shai Lighter released a mobile game based on Bini the Bunny's life.
The game is called Hoppy Brush, where players match colors to create paintings. In the game, Bini sells these paintings to help him rescue his mother.
All profits from the game go to the real-life Bini and Shai Lighter.
Awards
In October 2016, Bini the Bunny was recognized and awarded a record by Guinness World Records for most slam dunks by a rabbit in 60 seconds.
In 2017, the Facebook page for Bini the Bunny was recognized as "official" by Facebook. Bini has more than 200,000 Facebook fans.
In 2018, YouTube awarded Bini and Shai the Silver Creator Award for reaching and passing 100,000 subscribers.
In 2021. Bini became the first Rabbit to compete in America's Got Talent and pass the Judges Auditions level.
In 2021, Bini competed on World Pet Games on Fox - interspecies competitions - Bini's category was Dunk-Off, he won the bronze medal and broke his own record.
References
Further reading
Individual rabbits
2012 animal births
Animals on the Internet
Male mammals
Visual arts by animals
Animal world record holders | Bini the Bunny | [
"Biology"
] | 1,222 | [
"Ethology",
"Behavior",
"Animals",
"Visual arts by animals"
] |
53,160,480 | https://en.wikipedia.org/wiki/Magic%20polygon | A magic polygon is a polygonal magic graph with integers on its vertices.
Perimeter magic polygon
A magic polygon, also called a perimeter magic polygon, is a polygon with an integers on its sides that all add up to a magic constant. It is where positive integers (from 1 to N) on a k-sided polygon add up to a constant. Magic polygons are a generalization of other magic shapes such as magic triangles.
Magic polygon with a center point
Victoria Jakicic and Rachelle Bouchat defined magic polygons as n-sided regular polygons with 2n+1 nodes such that the sum of the three nodes are equal. In their definition, a 3 × 3 magic square can be viewed as a magic 4-gon. There are no magic odd-gons with this definition.
Magic polygons and degenerated magic polygons
Danniel Dias Augusto and Josimar da Silva defined the magic polygon P(n,k) as a set of vertices of concentric n-gon and a center point. In this definition, magic polygons of Victoria Jakicic and Rachelle Bouchat can be viewed as P(n,2) magic polygons. They also defined degenerated magic polygons.
See also
Magic square
References
External links
https://udayton.edu/artssciences/academics/mathematics/images_and_files/umd_proceedings_files/2018/Jakicic-journal.pdf
Magic figures | Magic polygon | [
"Mathematics"
] | 322 | [
"Recreational mathematics",
"Combinatorics stubs",
"Magic figures",
"Combinatorics"
] |
53,160,624 | https://en.wikipedia.org/wiki/Banu%20Subramaniam | Banu Subramaniam is a professor of women, gender and sexuality studies at the University of Massachusetts, Amherst. Originally trained as a plant evolutionary biologist, she writes about social and cultural aspects of science as they relate to experimental biology. She advocates for activist science that creates knowledge about the natural world while being aware of its embeddedness in society and culture. She co-edited Making Threats: Biofears and Environmental Anxieties (2005) and Feminist Science Studies: A New Generation (2001). Her book Ghost Stories for Darwin: The Science of Variation and the Politics of Diversity (2014) was chosen as a Choice Outstanding Academic Title in 2015 and won the Society for Social Studies of Science Ludwik Fleck Prize for science and technology studies in 2016. Her most recent book, Holy Science: The Biopolitics of Hindu Nationalism (2019), won the Michelle Kendrick Prize for the best book from the Society for Literature, Science, and the Arts in 2020.
Early life and education
Subramaniam grew up in India and received a baccalaureate degree from Stella Maris College at the University of Madras. She then attended Duke University, where she studied evolutionary plant biology, receiving a Ph.D. in evolutionary genetics. Her Ph.D. thesis was Maintenance of the Flower Color Polymorphism at the W Locus in the Common Morning Glory, Ipomoea purpurea (1994). While completing her Ph.D., she also earned a graduate certificate in women's studies.
Career
Subramaniam has held academic appointments at Harvard University, Northeastern University, the University of Arizona, the University of California, Irvine, and the University of North Carolina at Chapel Hill, where she directed the Women in Science program. In 1995, she was awarded a National Science Foundation grant for a faculty-student action project for graduate women in science and mathematics. In 2000, she received a National Science Foundation grant to study soil communities and their effects on invasive plant species. In 2001, she joined the department of women's studies at the University of Massachusetts, Amherst as an assistant professor. While at the University of Massachusetts, she was named a Distinguished Faculty Lecturer and awarded the Chancellor's Medal, which is the highest faculty honor for service to the university.
She has co-edited the books Making Threats: Biofears and Environmental Anxieties (2005) and Feminist Science Studies: A New Generation (2001). Her book Ghost Stories for Darwin: The Science of Variation and the Politics of Diversity (2014) is a "radically interdisciplinary feminist treatment" that examines the experimental practices of science through the histories of eugenics and genetics, and the ways in which historical ideas have informed our thinking about difference. Ghost Stories for Darwin explores the ghosts of racism and sexism that work to place limitations on who can be a knower, how one can come to know, and what can be known. She writes at the intersection of the social and the scientific to question how we understand variation and diversity, and her work encourages disruption of binary disciplinary thinking. Her most recent book is Holy Science: The Biopolitics of Hindu Nationalism (2019), which explores the interactions of religious nationalism and science in India. Holy Science includes case studies that consider the interconnections of science and religion, how they are shaped by their social contexts and structures of power, and how their aims can converge. Her current work in feminist science studies is focused on decolonizing botany by looking at post-colonial studies and biology.
Awards
Subramaniam received the 2016 Society for Social Studies of Science Ludwik Fleck Prize for science and technology studies for Ghost Stories for Darwin: The Science of Variation and the Politics of Diversity (2014). Ghost Stories for Darwin was also selected by Choice as an Outstanding Academic Title in 2015. Holy Science: The Biopolitics of Hindu Nationalism (2019) was awarded the Michelle Kendrick Prize for the best book from the Society for Literature, Science, and the Arts in 2020.
References
1966 births
Living people
Historians of science
Women science writers | Banu Subramaniam | [
"Technology"
] | 820 | [
"Women science writers",
"Women in science and technology"
] |
53,160,632 | https://en.wikipedia.org/wiki/Matthew%20Sigman | Matthew S. Sigman is an American chemist, focusing in Organic Synthesis & Asymmetric Catalysis. He is the Peter J. Christine S. Stang Presidential Endowed Chair and Distinguished Honors Professor at University of Utah and a Fellow of the American Association for the Advancement of Science.
References
Year of birth missing (living people)
Living people
University of Utah faculty
21st-century American chemists
American organic chemists
Sonoma State University alumni
Washington State University alumni
Fellows of the American Association for the Advancement of Science | Matthew Sigman | [
"Chemistry"
] | 103 | [
"Organic chemists",
"American organic chemists"
] |
53,162,555 | https://en.wikipedia.org/wiki/Walter%20Leal | Walter Soares Leal (born February 2, 1954) is a Brazilian biochemist and entomologist who is known for identifying pheromones and mosquito attractants, and elucidating a mechanism of action of the insect repellent DEET.
Leal was the first non-Japanese to earn tenure at the Ministry of Agriculture, Forestry, and Fisheries of Japan. In 2000, he accepted a position as associate professor at the University of California, Davis. Leal is a Distinguished Professor in the Department of Molecular and Cellular Biology. He served as chair of the entomology department at UC Davis (now Department of Entomology & Nematology).
Education and early life
Leal attended the Federal University of Pernambuco, from which he graduated in 1982 with a B.Eng degree in chemical engineering. In 1987, he got his MS in agricultural chemistry from Mie University in Tsu-Mie, Japan. While still residing in Japan, Leal attended the University of Tsukuba, division of Applied Biochemistry, graduating with a Ph.D. three years later. While in high school, Leal worked as a sports reporter to pay tuition and fees and later as a high school teacher – a career he started while a freshman in college, under the supervision of his favorite teacher, .
Research
Leal has identified complex pheromones from many insect species, including scarab beetles, true bugs, long-horned beetles, and moths. Intrigued by chiral discrimination by scarab beetles, he became interested in the molecular basis of insect olfaction. His laboratory discovered a pH-dependent conformational change in pheromone-binding proteins (PBPs) from moths before their 3D structures were known. In collaboration with Jon Clardy and Nobel Laureate Kurt Wuthrich, they determine the first 3D structures of PBPs. Subsequently, his laboratory studied the kinetics of pheromone binding and release by PBPs. Leal laboratory fully identified the first odorant-degrading enzymes from moths and scarab beetles. In 2005, Leal coined the term “reverse chemical ecology” for employing olfactory proteins to identify semiochemicals of potential practical applications. Using this approach, he identified oviposition attractants for mosquitoes. His laboratory identified olfactory receptor neurons (ORNs) highly sensitive to nonanal, which might play a crucial role in Culex mosquitoes shifting from birds to humans, implicated in West Nile virus transmission. Leal and his collaborators identified mosquito ORNs sensitive to DEET and subsequently identified an odorant receptor, CquiOR136, sensitive to DEET and other commercially available insect repellents. Leal and collaborators discovered a receptor, CquiOR32, with dual inhibitory/excitatory properties manifested in the Xenopus oocyte recording system, in flies and mosquito behavior. Leal laboratory demonstrated for the first time that mosquitoes respond to carbon dioxide with a heterodimer formed by GR2 and GR3, not as GR1/GR3 as previously hypothesized. They also demonstrated that per se, not bicarbonate, activates these receptors.
Leal is the author and co-author of more than 220 scientific articles.
Major services to the scientific community
Leal served as Councilor and President of the International Society of Chemical Ecology. Along with Alvin Simmons, Leal served as co-chair of the 2016 International Congress of Entomology. At the beginning of the COVID pandemic, Leal organized a series of COVID symposia, which drew thousands of attendees. In 2021, he organized a symposium, "Insect Olfaction and Taste in 24 Hours Around the Globe", to provide a platform for young scholars to highlight their recent work and interact with other well-established scholars in the field.
Awards
Member of the National Academy of Sciences (2024)
Honorary Member, Entomological Society of America
Academic Senate's 2022 Distinguished Scholarly Public Service Award
Distinguished Teaching Award for Undergraduate Teaching, UC Davis Academic Senate (2020)
Award for Excellence in Teaching, Pacific Branch of the Entomological Society of America (2020)
Founders’ Memorial Award, Entomological Society of America (2019)
Fellow of the National Academy of Inventors (2019)
Fellow of the California Academy of Sciences (2015)
Honorary Fellow of the Royal Entomological Society (2015),
Corresponding Member, Brazilian Academy of Sciences (2012)
Silver Medal, International Society of Chemical Ecology (2012)
Nan-Yao Su Award for Innovation and Creativity in Entomology (2011)
Fellow of the Entomological Society of America (2008)
Fellow of the American Association for the Advancement of Science (2005)
Gakkai-show (Fellow-like award), Japanese Society of Applied Entomology and Zoology (1998)
Entomological Society of Brazil Award, Medal of Achievement (1995)
Gijitsusho (Technology Prize), Japan Society for Bioscience, Biotechnology & Agrochemistry (1994)
References
External links
1954 births
Living people
American entomologists
Federal University of Pernambuco alumni
University of Tsukuba alumni
University of California, Davis faculty
Fellows of the American Association for the Advancement of Science
Fellows of the Entomological Society of America
Fellows of the Royal Entomological Society
Members of the Brazilian Academy of Sciences
Chemical ecologists | Walter Leal | [
"Chemistry"
] | 1,094 | [
"Chemical ecologists",
"Chemical ecology"
] |
53,162,915 | https://en.wikipedia.org/wiki/Yangon%20Planetarium | Yangon Planetarium is a planetarium located in Myanmar's largest city, Yangon. It presents a half-hour star show illuminated against the planetarium's domes ceiling. The building was donated by the government of Japan in 1987. On the grounds, there is also a 70s-era Myanma Airways plane exhibited a walk-thru exhibit.
References
Museums in Yangon
Museums in Myanmar
Planetaria | Yangon Planetarium | [
"Astronomy"
] | 84 | [
"Astronomy education",
"Astronomy organizations",
"Planetaria"
] |
53,163,128 | https://en.wikipedia.org/wiki/Space-based%20measurements%20of%20carbon%20dioxide | Space-based measurements of carbon dioxide () are used to help answer questions about Earth's carbon cycle. There are a variety of active and planned instruments for measuring carbon dioxide in Earth's atmosphere from space. The first satellite mission designed to measure was the Interferometric Monitor for Greenhouse Gases (IMG) on board the ADEOS I satellite in 1996. This mission lasted less than a year. Since then, additional space-based measurements have begun, including those from two high-precision (better than 0.3% or 1 ppm) satellites (GOSAT and OCO-2). Different instrument designs may reflect different primary missions.
Purposes and highlights of findings
There are outstanding questions in carbon cycle science that satellite observations can help answer. The Earth system absorbs about half of all anthropogenic emissions. However, it is unclear exactly how this uptake is partitioned to different regions across the globe. It is also uncertain how different regions will behave in terms of flux under a different climate. For example, a forest may increase uptake due to the fertilization or β-effect, or it could release due to increased metabolism by microbes at higher temperatures. These questions are difficult to answer with historically spatially and temporally limited data sets.
Even though satellite observations of are somewhat recent, they have been used for a number of different purposes, some of which are highlighted here:
Megacity enhancements were observed with the GOSAT satellite and minimum observable space-based changes in emissions were estimated.
Satellite observations have been used for visualizing how is distributed globally, including studies that have focused on anthropogenic emissions.
Flux estimates were made of into and out of different regions.
Correlations were observed between anomalous temperatures and measurements in boreal regions.
Zonal asymmetric patterns of were used to observe fossil fuel signatures.
Emission ratios with methane were measured from forest fires.
emission ratios with carbon monoxide (a marker of incomplete combustion) measured by the MOPITT instrument were analyzed over major urban regions across the globe to measure developing/developed status.
OCO-2 observations were used to estimate emissions from wildfires in Indonesia in 2015.
OCO-2 observations were also used to estimate the excess land-ocean flux due to the 2014–16 El Niño event.
GOSAT observations were used to attribute 2010-2011 El Niño Modoki on the Brazilian carbon balance.
OCO-2 observations were used to quantify emissions from individual power plants, demonstrating the potential for future space-based emission monitoring.
Challenges
Remote sensing of trace gases has several challenges. Most techniques rely on observing infrared light reflected off Earth's surface. Because these instruments use spectroscopy, at each sounding footprint a spectrum is recorded—this means there is a significantly (about 1000×) more data to transfer than what would be required of just an RGB pixel. Changes in surface albedo and viewing angles may affect measurements, and satellites may employ different viewing modes over different locations; these may be accounted for in the algorithms used to convert raw into final measurements. As with other space-based instruments, space debris must be avoided to prevent damage.
Water vapor can dilute other gases in air and thus change the amount of in a column above the surface of the Earth, so often column-average dry-air mole fractions (X) are reported instead. To calculate this, instruments may also measure O, which is diluted similarly to other gases, or the algorithms may account for water and surface pressure from other measurements. Clouds may interfere with accurate measurements so platforms may include instruments to measure clouds. Because of measurement imperfections and errors in fitting signals to obtain X, space-based observations may also be compared with ground-based observations such as those from the TCCON.
List of instruments
Partial column measurements
In addition to the total column measurements of down to the ground, there have been several limb sounders that have measured through the edge of Earth's upper atmosphere, and thermal instruments that measure the upper atmosphere during the day and night.
Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) onboard TIMED launched 7 December 2001 makes measurements in the mesosphere and lower thermosphere in thermal bands.
ACE-FTS (Atmospheric Chemistry Experiment-Fourier Transform Spectrometer) onboard SCISAT-1 launched 13 August 2003 measures solar spectra, from which profiles of can be calculated.
SOFIE (Solar Occultation for Ice Experiment) is a limb sounder on board the AIM satellite launched 25 April 2007.
Conceptual Missions
There have been other conceptual missions which have undergone initial evaluations but have not been chosen to become a part of space-based observing systems. These include:
Active Sensing of Emissions over Nights, Days, and Seasons (ASCENDS) is a lidar-based mission
Geostationary Fourier Transform Spectrometer (GeoFTS)
Atmospheric Imaging Mission for Northern regions (AIM-North) would involve a constellation of two satellites in elliptical orbits to focus on northern regions. The concept is undergoing a Phase 0 study in 2019–2020.
Carbon Monitoring Satellite (CarbonSat) was a concept for an imaging satellite with global coverage approximately every 6 days. This mission never proceeded beyond the concept phase.
References
Satellite meteorology
Atmosphere of Earth
Carbon dioxide
Satellites monitoring GHG emissions | Space-based measurements of carbon dioxide | [
"Chemistry"
] | 1,066 | [
"Greenhouse gases",
"Carbon dioxide"
] |
53,163,163 | https://en.wikipedia.org/wiki/NGC%20417 | NGC 417 is a lenticular galaxy of type SAB0− located in the constellation Cetus. It was discovered in 1886 by Francis Leavenworth. It was described by Dreyer as "extremely faint, extremely small, round."
References
External links
0417
Astronomical objects discovered in 1886
Cetus
Lenticular galaxies
004237 | NGC 417 | [
"Astronomy"
] | 68 | [
"Cetus",
"Constellations"
] |
53,163,190 | https://en.wikipedia.org/wiki/NGC%20418 | NGC 418 is a barred spiral galaxy of type SB(s)c located in the constellation Sculptor. It was discovered on September 28, 1834 by John Herschel. It was described by Dreyer as "faint, pretty large, round, very gradually a little brighter middle, western of 2.", the other being NGC 423.
References
External links
0418
18340928
Sculptor (constellation)
Barred spiral galaxies
004189 | NGC 418 | [
"Astronomy"
] | 91 | [
"Constellations",
"Sculptor (constellation)"
] |
53,163,575 | https://en.wikipedia.org/wiki/Avinash%20Kumar%20Agarwal | Avinash Kumar Agarwal (born 22 August 1972) is director of Indian Institute of Technology, Jodhpur. He is an Indian mechanical engineer, tribologist and a professor at the Department of Mechanical Engineering of the Indian Institute of Technology, Kanpur. He is known for his studies on internal combustion engines, Emissions, alternate fuels and CNG engines and is an elected fellow of the American Society of Mechanical Engineering (2013), Society of Automotive Engineers, US (2012), National Academy of Science, Allahabad (2018), Royal Society of Chemistry, UK (2018), International Society for Energy, Environment and Sustainability (2016), and Indian National Academy of Engineering (2015). The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards for his contributions to Engineering Sciences in 2016. Agarwal has been bestowed upon Prestigious J C Bose Fellowship of Science and Engineering Research Board. Government of India (August 2019). Agarwal is among the top ten highly cited researchers (HCR) of 2018 from India, as per Clarivate Analytics, an arm of Web of Science.
Biography
Avinash Kumar Agarwal, born on 22 August 1972 at Karauli, in the Indian state of Rajasthan, earned his graduate degree in mechanical engineering (BE) from Malaviya Regional Engineering College (MREC) Jaipur (present-day Malaviya National Institute of Technology, Jaipur) of the University of Rajasthan in 1994 and did his master's degree at the Centre for Energy Studies of the Indian Institute of Technology, Delhi from where he obtained an MTech in energy studies in 1996. immediately after this, he pursued his PhD at IIT Delhi, in Center for energy studies, under the guidance of L. M. Das, which he successfully defended in 1999 for his thesis, Performance evaluation and tribological studies on a biodiesel-fuelled compression ignition engine. Thereafter he moved to the US for his postdoctoral work which he completed at the Engine Research Center of the University of Wisconsin-Madison between 1999 and 2001. On his return to India in March 2001, he joined the Indian Institute of Technology, Kanpur as an assistant professor. He was promoted as an associate professor in 2007 and has been serving the institute since 2012 as a professor at the Department of Mechanical Engineering. He had seven short stints abroad as visiting professor during this period, first at Wolfson School of Mechanical and Manufacturing Engineering of the University of Loughborough in 2002 second and third, at Photonics Institute of Technical University of Vienna in 2004 and 2013, and the fourth, fifth and sixth at Hanyang University, South Korea in 2013, 2014 and 2015 and the last stint at Korea Advanced Institute of Science and Technology (KAIST) in 2016. On 19 April 2024, he was appointed as the director of IIT Jodhpur.
Agarwal is married to Dr. Rashmi A. Agarwal and the couple has two children, Aditya (b. 2003) and Rithwik (b. 2006). The family lives in Kanpur in Uttar Pradesh.
Legacy
Agrawal's researches has covered the fields of engine combustion, alternate fuels, emission and particulate control, optical diagnosis, Methanol Engine Development, fuel spray optimization and tribology and his work has assisted in the development of low-cost diesel oxidation catalysts and homogeneous charge compression ignition engines. His studies of laser ignition of methane-air hydrogen-air mixtures and biodiesel based on Indian feedstocks have widened the understanding of the subjects; he carried out a project on biodiesels during 2010–13 for the Department of Science and Technology of India. He has documented his researches by way of over 280 articles; Google Scholar and ResearchGate, online repositories of scientific articles, have listed many of them. Besides, he has edited forty books, most of which are published by Springer, including, Combustion for Power Generation and Transportation, and Novel Combustion Concepts for Sustainable Energy Development and has contributed forty two chapters to many books. He is also a co-editor of a five-volume reference text, Handbook of Combustion, published by Wiley-VCH in 2010.
Agarwal is the Associate Principle Editor of Journal "Fuel", Editor-in-chief of Journal of Energy and Environmental Sustainability (JEES) and is Associate Editor of two other journals, "ASME Journal of Energy Resources Technology", and "Journal of the Institution of Engineers (India): Series C". He is a member of the editorial board of several prestigious journals such as "International Journal of Engine Research, published by SAE International and IMechE, London, UK", Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering and Recent Patents on Mechanical Engineering of Bentham Science. He is also a former associate editor of the International Journal of Vehicle Systems Modelling and Testing of Inderscience Publishers, "International Journal of Oil, Gas and Coal Technology" (IJOGCT), Published by Inderscience Publishers and guest-edited a special issue of the Journal of Automobile Engineering on Alternative Fuels in 2007. He is a member of the Methanol Task Force of the Department of Science and Technology since 2017, former member of Technology Systems Group of the Department of Science and Technology and a former member of the Experts Group on Biofuels and Retrofitting of Engines of the Government of India. He is a member of the board of associates of the Internal Combustion Engines Division of American Society of Mechanical Engineering and is associated with SAE International, sitting in many of their review committees.
He was the session organizer for 2005, 2006, 2007, 2008 and 2009 editions of SAE World Congress and chaired the 2004, 2005 and 2006 sessions on alternative fuel and internal combustion engines.
Awards and honors
Agarwal received the Young Scientist Award of the Department of Science and Technology in 2002, followed by the Career Award for Young Teachers of the All India Council of Technical Education (AICTE) in 2004. The Young Engineer Award of the Indian National Academy of Engineering reached him in 2005 and the Young Scientists Medal of the Indian National Science Academy came his way in 2007. He received the Alkyl Amine Young Scientist Award of the Institute of Chemical Technology the same year and a year later, SAE International selected him for the 2008 Ralph R. Teetor Educational Award. He received the C. V. Raman Young Teachers Award of the IES Group in 2011 and NASI-Reliance Industries Platinum Jubilee Award of the National Academy of Sciences, India in 2012. The Indian National Academy of Engineering honored him again in 2012 with the Silver Jubilee Young Engineer Award, which was followed by "Rajib Goyal Prize" in Physical Sciences-2015 from Kurukshetra University and then Council of Scientific and Industrial Research awarded him the Shanti Swarup Bhatnagar Prize, one of the highest Indian science awards in 2016. Afterwards, he was conferred "Er. M P Baya National Award-2017" in Mechanical Engineering by Institution of Engineers, Udaipur and Clarivate Analytics India Research Excellence - Citation Award-2017, which was 6th Edition prize for high citations and high impact work from India, given by Clarivate Analytics.
Agarwal, who held the BOYSCAST Fellowship of Department of Science and Technology in 2002 and Devendra Shukla Research Fellowship of IIT Kanpur in 2009, was elected as a fellow by the Indian National Academy of Engineering in 2015. He is also a fellow of the American Society of Mechanical Engineers and SAE International, Royal Society of Chemistry, Indian National Academy of Engineering, National Academy of Sciences and International Society for Energy, Environment and Sustainability He was listed in several editions of Marquis Who's Who in Science and Engineering, Who's Who (Emerging Leaders) and Who's Who in the World. Agarwal was Poonam and Prabhu Goyal Chair Professor at IIT Kanpur from 2012 to 2016. He is currently SBI Endowed chair Professor in the same institution (2018-2021).
Selected bibliography
Books
Environmental Contaminants, 431 pages, Published by Springer, Singapore (2018), (Eds.) Tarun Gupta, Avinash K Agarwal, Rashmi A Agarwal, Nitin K Labhsetwar () DOI: 10.1007/978-981-10-7332-8.
Air Pollution and Control, 260 pages, Published by Springer, Singapore (2018), (Eds.) Nikhil Sharma, Avinash K Agarwal, Peter Eastwood, Tarun Gupta, Akhilendra P Singh () DOI: 10.1007/978-981-10-7185-0.
Coal and Biomass Gasification, 521 pages, Published by Springer, Singapore (2018), (Eds.) Santanu De, Avinash K Agarwal, V S Moholkar, Thallada Bhaskar () DOI: 10.1007/978-981-10-7335-9.
Droplets and Sprays, 430 pages, Published by Springer, Singapore (2018), (Eds.) Saptarshi Basu, Avinash K Agarwal, Achintya Mukhopadhyay, Chetan Patel () DOI: 10.1007/978-981-10-7449-3.
Advances in Internal Combustion Engine Research, 345 pages, Published by Springer, Singapore (2018), (Eds.) Dhananjay K Srivastava, Avinash K Agarwal, Amitava Datta, Rakesh K Maurya () DOI: 10.1007/978-981-10-7575-9.
Modeling and Simulations of Turbulent Combustion, 661 pages, Published by Springer, Singapore (2018), (Eds.) Santanu De, Avinash K Agarwal, Swetoprovo Chaudhuri, Swarnendu Sen () DOI: 10.1007/978-981-10-7410-3.
Prospects of Alternative Transportation Fuels, 405 pages, Published by Springer, Singapore (2018), (Eds.) Akhilendra P Singh, Avinash K Agarwal, Rashmi A Agarwal, Atul Dhar, Mritunjay Kumar Shukla () DOI: 10.1007/978-981-10-7518-6.
Environmental, Chemical and Medical Sensors, 409 pages, Published by Springer, Singapore (2018), (Eds.) Shantanu Bhattacharya, Avinash K Agarwal, Nripen Chanda, Ashok Pandey, Ashis Kumar Sen () DOI: 10.1007/978-981-10-7751-7.
Applications of Solar Energy, 364 pages, Published by Springer, Singapore (2018), (Eds.) Himanshu Tyagi, Avinash K Agarwal, Prodyut R Chakraborty, Satvasheel Powar () DOI: 10.1007/978-981-10-7206-2.
Bioremediation: Applications for Environmental Protection and Management, 411 pages, Published by Springer, Singapore (2018), (Eds.) Sunita J Varjani, Avinash K Agarwal, Edgard Ghansounou, Baskar Gurunathan () DOI: 10.1007/978-981-10-7485-1.
Applications Paradigms of Droplet and Spray Transport: Paradigms and Applications, 379 pages, Published by Springer, Singapore (2018), (Eds.) Saptarshi Basu, Avinash K Agarwal, Achintya Mukhopadhyay, Chetan Patel () DOI: 10.1007/978-981-10-7233-8.
Combustion for Power Generation and Transportation: Technology, Challenges and Prospects, 451 pages, Published by Springer, Singapore (2017), (Eds.) Avinash Kumar Agarwal, Santanu De, Ashok Pandey, Akhilendra Pratap Singh (). DOI: 10.1007/978-981-10-3785-6.
Locomotives and Rail Road Transportation: Technology, Challenges and Prospects, 247 pages, Published by Springer, Singapore (2017), (Eds.) Avinash Kumar Agarwal, Atul Dhar, Anirudh Gautam, Ashok Pandey (). DOI: 10.1007/978-981-10-3788-7.
Biofuels: Technology, Challenges and Prospects, 245 pages, Published by Springer, Singapore (2017), (Eds.) Avinash Kumar Agarwal, Rashmi Avinash Agarwal, Tarun Gupta, Bhola Ram Gurjar. DOI: 10-1007/978-981-10-3791-7 (). DOI: 10.1007/978-981-10-3791-7.
Technology Vision 2015: Technology Roadmap Transportation, 237 pages, (Eds.) Avinash Kumar Agarwal, S S Thipse, Akhilendra P Singh, Gautam Goswami, Mukti Prasad, Published by TIFAC, New Delhi, December 2016.
Energy, Combustion and Propulsion: New Perspectives, 609 pages, Published by Athena Academic, London, UK (2016), (Eds.) Avinash K Agarwal, Suresh K. Aggarwal, Ashwani K. Gupta, Abhijit Kushari, Ashok Pandey ()
Novel Combustion Concepts for Sustainable Energy Development, 562 pages, Published by Springer, Singapore (2014), (Eds.) Avinash K. Agarwal, Ashok Pandey, Ashwani K. Gupta, Suresh K. Aggarwal, Abhijit Kushari. (). DOI: 10.1007/978-81-322-2211-8-18.
Handbook of Combustion, 5 Volumes, 3168 pages, Hardcover, April 2010, Published by Wiley VCH, (Eds.) Maximilian Lackner, Franz Winter, Avinash K. Agarwal ().
CI Engine Performance for Use with Alternative Fuels, 2009(SP-2237), 185 pages, Published by SAE International, US, 2009, (Eds.) Amiyo K Basu, Avinash Kumar Agarwal, Paul Richards, G. J. Thompson, Scott A Miers, Sundar Rajan Krishnan ().
Combustion Science and Technology: Recent Trends Published by Narosa Publishing House, New Delhi, 2009 (Eds.) A. K. Agarwal, A. Kushari, S. K. Aggarwal, A. K. Runchal, 300 Pages ().
CI Engine Performance for use with Alternative Fuels (SP-2176), Published by SAE International, US, 2008, (Eds.) Avinash K. Agarwal, G. J. Thompson, Scott A. Miers, Sundar R. Krishnan ().
Alternative Fuels and CI Engine Performance (SP-2067), 160 Pages, Published by SAE International, US, 2007, (Eds.) Avinash K. Agarwal, G. J. Thompson ().
New Diesel Engines and Components and CI Engine performance for Use with Alternative Fuels (SP-2014), 171 Pages, Published by SAE International, US, 2006, (Eds.) A. Jain, J. E. Mossberg, Avinash K. Agarwal, G. J. Thompson ().
CI Engine performance for Use with Alternative Fuels, and New Diesel Engines and Components (SP-1978), 196 Pages, Published by SAE International, US, 2005, (Eds.) J. E. Mossberg, A. Jain, G. J. Thompson, Avinash K. Agarwal ().
Articles
Avinash K Agarwal*, Bushra Ateeq, Tarun Gupta, Akhilendra P. Singh, Swaroop K Pandey, Nikhil Sharma, Rashmi A Agarwal, Neeraj K. Gupta, Hemant Sharma, Ayush Jain, Pravesh C Shukla, "Toxicity and mutagenicity of exhaust from compressed natural gas: Could this be a clean solution for megacities with mixed-traffic conditions?”, Environmental Pollution. 239, 499–511, 2018.doi: 10.1016/j.envpol.2018.04.028
See also
Diesel fuel
Vegetable oil
References
Further reading
Recipients of the Shanti Swarup Bhatnagar Award in Engineering Science
1972 births
Indian technology writers
People from Rajasthan
Indian mechanical engineers
Tribologists
University of Rajasthan alumni
IIT Delhi alumni
Academic staff of IIT Delhi
Academic staff of IIT Kanpur
Academics of Loughborough University
Living people
Fellows of the Indian National Academy of Engineering
University of Wisconsin–Madison fellows | Avinash Kumar Agarwal | [
"Materials_science"
] | 3,545 | [
"Tribology",
"Tribologists"
] |
53,165,511 | https://en.wikipedia.org/wiki/Characterization%20of%20probability%20distributions | In mathematics in general, a characterization theorem says that a particular object – a function, a space, etc. – is the only one that possesses properties specified in the theorem. A characterization of a probability distribution accordingly states that it is the only probability distribution that satisfies specified conditions. More precisely, the model of characterization of
probability distribution was described by in such manner. On the probability space we define the space of random variables with values in measurable metric space and the space of random variables with values in measurable metric space . By characterizations of probability distributions we understand general problems of description of some set in the space by extracting the sets and which describe the properties of random variables and their images , obtained by means of a specially chosen mapping .
The description of the properties of the random variables and of their images is equivalent to the indication of the set from which must be taken and of the set into which its image must fall. So, the set which interests us appears therefore in the following form:
where denotes the complete inverse image of in . This is the general model of characterization of probability distribution. Some examples of characterization theorems:
The assumption that two linear (or non-linear) statistics are identically distributed (or independent, or have a constancy regression and so on) can be used to characterize various populations. For example, according to George Pólya's characterization theorem, if and are independent identically distributed random variables with finite variance, then the statistics and are identically distributed if and only if and have a normal distribution with zero mean. In this case
,
is a set of random two-dimensional column-vectors with independent identically distributed components, is a set of random two-dimensional column-vectors with identically distributed components and is a set of two-dimensional column-vectors with independent identically distributed normal components.
According to generalized George Pólya's characterization theorem (without condition on finiteness of variance ) if are non-degenerate independent identically distributed random variables, statistics and are identically distributed and , then is normal random variable for any . In this case
,
is a set of random n-dimensional column-vectors with independent identically distributed components, is a set of random two-dimensional column-vectors with identically distributed components and is a set of n-dimensional column-vectors with independent identically distributed normal components.
All probability distributions on the half-line that are memoryless are exponential distributions. "Memoryless" means that if is a random variable with such a distribution, then for any numbers ,
.
Verification of conditions of characterization theorems in practice is possible only with some error , i.e., only to a certain degree of accuracy. Such a situation is observed, for instance, in the cases where a sample of finite size is considered. That is why there arises the following natural question. Suppose that the conditions of the characterization theorem are fulfilled not exactly but only approximately. May we assert that the conclusion of the theorem is also fulfilled approximately? The theorems in which the problems of this kind are considered are called stability characterizations of probability distributions.
See also
Characterization (mathematics)
References
Probability theorems
Theorems in statistics | Characterization of probability distributions | [
"Mathematics"
] | 643 | [
"Mathematical problems",
"Theorems in probability theory",
"Mathematical theorems",
"Theorems in statistics"
] |
53,165,654 | https://en.wikipedia.org/wiki/Descriptor%20%28chemistry%29 | In chemical nomenclature, a descriptor is a notational prefix placed before the systematic substance name, which describes the configuration or the stereochemistry of the molecule. Some of the listed descriptors should not be used in publications, as they no longer accurately correspond with the recommendations of the IUPAC. Stereodescriptors are often used in combination with locants to clearly identify a chemical structure unambiguously.
The descriptors, usually placed at the beginning of the systematic name, are not taken into account in the alphabetical sorting.
Configuration descriptors
cis, trans
See: cis–trans isomerism
The descriptors cis (Latin, on this side of) and trans (Latin, over, beyond) are used in various contexts for the description of chemical configurations:
In organic structural chemistry, the configuration of a double bond can be described with cis and trans, in case it has a simple substitution pattern with only two residues. The position of two residues relative to one another at different points in a ring system or a larger molecule can also be described with cis and trans if the structure's configuration is rigid and does not allow simple inversion.
In inorganic complex chemistry, the descriptors cis and trans are used to characterize the positional isomers in octahedral complexes with A2B4X configuration or square planar complexes with A2B2X configuration.
The typographic presentation of cis and trans is italicised and in lower case letters.
The cis/trans nomenclature is not unambiguous for more highly substituted double bonds and is nowadays largely replaced by the (E)/(Z) nomenclature.
(E), (Z)
See: E-Z notation
The descriptors (E) (from German entgegen, 'opposite') and (Z) (from German zusammen, 'together') are used to provide a distinct description of the substitution pattern for alkenes, cumulenes or other double bond systems such as oximes.
For the attribution of (E) or (Z) is based on the relative position of the two substituents of highest priority are on each side of the double bond, while the priority is based on the CIP nomenclature. The (E)/(Z) nomenclature can be applied to any double bond systems (including heteroatoms), but not to substituted ring systems. The descriptors (E) and (Z) are always capitalized, set italic, and surrounded by parentheses that are set as normal just like additional locants or commas.
o-, m-, p-
See: Arene substitution pattern
The abbreviation o- (short for ortho, from Greek orthós for upright, straight), m- (meta, Greek (roughly) for between) and p- (para, from Greek pará for adjoining, to the side) describe the three possible positional isomers of two substituents on a benzene ring. These are usually two independent single substituents, but in case of fused ring systems, ortho-fusing is also mentioned unless the substitution pattern is regarded in the name like in [2.2]paracyclophane. In the current systematic nomenclature, o-, m- and p- are often replaced by using locants (1,2-dimethylbenzene instead of o-xylene).
o-, m- and p- (written out ortho-, meta- and para-) are written in lowercase letters and italic.
exo, endo
See: Endo-exo isomerism
exo (from Greek = outside) or endo (from Greek endon = inside) denotes the relative configuration of bridged bicyclic compounds. The position of a substituent in the main ring relative to the shortest bridge is decisive for the assignment of exo or endo (according to IUPAC: the bridge with the highest locant digits in the bridged ring system). The substituent to be classified is attributed with the exo descriptor when facing the bridge. It is endo configured when facing away from the bridge. If two different substituents are located on the same C atom, the exo/endo assignment is based on the substituent with higher priority according to the CIP rules.
syn, anti
If a bridged bicyclic system carries a substituent at the shortest bridge, the exo or endo descriptor can not be used for its assignment. Such isomers are classified by the syn/anti notation. If the substituent to be assigned points towards the ring with the highest number of segments it is syn configured (from Greek syn = together). Otherwise it is attributed with the anti descriptor (Greek anti = against). If both rings possess an equal number of segments the ring with the most significant substituent according to the CIP rules is chosen.
The use of syn and anti to indicate the configuration of double bonds is nowadays obsolete, especially in case of aldoximes and hydrazones derived from aldehydes. Here, the compounds were designated as syn configured when the aldehyde H and the O (of the oxime) or the N (of the hydrazone) were cis aligned. These compounds are now described by the (E)/(Z) nomenclature. Aldoximes and hydrazones classified as syn are therefore by now described as (E) configurated.
When talking of diastereomers, syn and anti are used to describe groups on the same or opposite sites in zigzag prijection, see Diastereomer#Syn / anti
syn and anti are always written small and italic, locants (if used) are placed in front of the word and separated by hyphens.
fac, mer
The terms fac (from Latin facies, 'external face') and mer (from 'meridional') can specify the arrangement of three identical ligands around the central atom in octahedral complexes. Today, this nomenclature is considered obsolete, but is still permissible. The prefix fac describes the situation when the three identical ligands occupy the three vertices of an octahedron triangular surface. In mer configuration the three ligands span a plane in which the central atom is located.
fac and mer are prefixed in small and italic to the complex name.
n, iso, neo, cyclo
The prefixes n (normal), iso (from Greek ísos = equal), neo (Greek néos = young, new) and cyclo (Greek kyklos = circle) are primarily used to describe the arrangement of atoms, usually of carbon atoms in carbon skeleton. n, iso and neo are no longer used in the systematic nomenclature, but still frequently in trivial names and in laboratory jargon.
The prefix n describes a straight-chain carbon skeleton without branches, whereas iso describes a branched skeleton, without specifying any further details. More generally, iso is a compound which is isomeric to the n compound (a compound in which individual atoms or atomic groups are rearranged)
neo is a non-specific term for "new", usually synthetically produced substances or isomers of long-known n compounds or natural substances (for example neomenthol derived from menthol or neoabietic acid from abietic acid). According to IUPAC neo is only recommended in neopentane or the neopentyl residue.
cyclo is a frequently used prefix for all cyclic and heterocyclic compounds. In many proper names of chemical substances cyclo is not used as a prefix but directly part of the name, for example in cyclohexane or cyclooctatetraene.
While n, iso and neo are written in small and italic letters, for cyclo this is only the case in inorganic compounds. In organic compounds, "cyclo" is frequently used as a name component, not separated by a hyphen and also considered in alphabetical sorting.
sec-, tert-
The prefixes sec and tert are used to indicate the substituent environment in a molecule. Thus, not the exact position of the substituent is described but only the substitution pattern of the adjacent atom (usually a carbon atom). In n-butanol, the OH group is attached to a primary carbon atom, in sec-butanol to a secondary carbon and in tert-butanol to a tertiary carbon atom.
The terms sec and tert are considered obsolete and should only be used for unsubstituted sec-butoxy, sec-butyl or tert-butyl groups. There are various spellings such as "sec-butyl", "s-butyl", "sBu" or "bus" which are also considered obsolete.
spiro
The prefix "spiro" followed by a Von-Baeyer descriptor describes in the nomenclature of organic compounds ring systems linked by only one common atom, the spiro atom. If several spiro atoms are present in the molecule, the prefix "spiro" is provided with a prefix ("dispiro", "trispiro", etc.) corresponding to the number of spiro atoms. Typically "spiro" is set as normal.
catena
The term catena (Latin: "chain") is used in the inorganic nomenclature to describe linear, chain-like polymers from identical polyatomic units. One example is are catenatriphosphazenes. Related compounds in organic chemistry are the catenanes.
sn
The notation sn stands for stereospecific numbering, and indicates a particular way of numbering the carbon atoms in a molecule based on glycerol.
Stereodescriptors of absolute configurations
(R), (S)
See: Cahn–Ingold–Prelog priority rules
The stereochemical descriptors (R) (from Latin rectus = right) and (S) (from lat. sinister = left) are used to describe the absolute configuration of a stereocenter (usually a chiral carbon atom). For this purpose, all substituents at the stereocentre are prioritized according to the CIP rules and the substituent with the lowest priority ("D") is pointed backwards (away from the viewing direction). The stereocenter is (S) configured if the remaining substituents describe a circle descending in priority ("A" → "B" → "C") to the left. The (R) configuration is assigned to the stereocenter if the direction of rotation is directed to the right.
If one molecule contains several stereocenters, a locant must be placed before the descriptor (for example, in (1R, 2S)-2-amino-1-phenylpropan-1-ol, the systematic designation of norephedrine). If all stereocenters are configured the same, the naming of the locants can be omitted in favor of an "all-R" or "(all-S)" spelling.
Typographically, (R) and (S) are placed in uppercase and italic; the frequently preceding locants, the enclosing round brackets and the commas, on the other hand, as normal.
(r), (s)
The descriptors (r) and (s) are used to describe the absolute configuration of pseudoasymmetric centers. Pseudoasymmetry occurs when four different substituents are attached to one carbon atom, two of which differ only by their absolute stereochemical configuration. Examples of such are meso compounds such the tropane alkaloids; the parent compound is tropine, whose systematic name is (1R, 3r, 5S)-8-methyl-8-azabicyclo[3.2.1]octane-3-ol. In this structure, the C3 atom—the carbon to which the hydroxyl group is attached—is pseudo-asymmetric; therefore, the stereochemical descriptor in the systematic name is written in lower-case italics rather than upper-case italics as for regular chiral atoms.
D-, L-
See: Fischer projection
The stereoscriptors D- (from Latin dexter, right) and L- (Latin laevus, left) are used to describe the configuration of α-amino acids and sugars. First, the three-dimensional molecule must be transformed in a defined notation as a two-dimensional image ("Fischer projection"). For this, the C atom with the highest priority according to the normal nomenclature rules is arranged on top and the further carbon chain is arranged vertically underneath. The chiral C-atom most remote from the group with the highest priority is used for the assignment of D- or L-. If the residue located on this carbon atom (usually an OH group) points to the left, the molecule originates from the L-series. If the residue points to the right, the descriptor D- is used.
The descriptors D- and L- are written as small capitals and separated by a hyphen from the rest of the name.
d-, l-
Sometimes the small capital D- and L- stereodescriptors mentioned above are mistakenly confused with the obsolete italic d- and l- stereodescriptors, which are equivalent with dextrorotatory and levorotatory optical rotation, i.e. (+)- and (−)- stereodescriptors, respectively.
References
Chemical nomenclature | Descriptor (chemistry) | [
"Chemistry"
] | 2,856 | [
"nan"
] |
53,165,774 | https://en.wikipedia.org/wiki/Nuclear%20sexing | Nuclear sexing is a technique for genetic sex determination in those species where XX chromosome pair is present. Nuclear sexing can be done by identifying Barr body, a drumstick like appendage located in the rim of the nucleus in somatic cells. Barr body is the inactive X chromosome which lies condensed in the nucleus of somatic cells. A typical human (or other XY-based organism) female has only one Barr body per somatic cell, while a typical human male has none. Though a Barr body can be sought in any human nucleated cell, circulating mononuclear cells are commonly used for this purpose. These cells are cultured, and treated with chemicals such as colcemid to arrest mitosis in metaphase.
A minimum of 30 percent of sex chromatin indicates genetic female sex.
See also
Sex-determination system
References
Sex-determination systems
Genetics | Nuclear sexing | [
"Biology"
] | 181 | [
"Sex-determination systems",
"Sex"
] |
53,166,591 | https://en.wikipedia.org/wiki/Breast%20physics | In video games, breast physics or jiggle physics are a feature that makes a female character's breasts bounce when she moves, sometimes in an exaggerated or unnatural manner.
History
The first video game in which breast physics were a notable feature was the fighting game Fatal Fury 2 (1992), which featured the fighter Mai Shiranui, who had noticeably jiggly breasts. Pronounced breast physics have since remained a staple feature of many fighting games, perhaps in part because these games contain fewer character models than other games and can therefore afford to animate their characters in more detail. The Dead or Alive series (1996–), in particular, has become identified with the "outlandish" physics of both its fighting moves and its female characters' breasts; its developer Team Ninja created the term "breast physics".
On occasion, this aspect of fighting games has caused particular attention, such as when the 2016 game Street Fighter V had the fighter Chun-Li's breasts move like large water balloons when she was chosen as the second player's character in the selection screen. Although this behavior was noticed by media even before the game's release, it remained present in the released version of the game. The game's publisher Capcom attributed it to a bug and later removed it by a patch.
In reaction to the prevalence of big, bouncy breasts in video games, games writer Jenn Frank initiated a "boob jam" in 2013. The purpose of the initiative was to create games that deal "with an aspect of female breasts other than the fact that they're sexy and fun to look at".
Technology
Breast physics is an application of soft-body dynamics, the field of computer graphics that focuses on physical simulations of the motion and properties of deformable objects. In a game with 3D graphics, character models are composed of a skeleton of "bones" connected with joints and covered by a "skin" of textured polygons. These virtual bones do not necessarily correspond to the bones in real humans, but are required to make anything move. To make breasts or other body parts move, video game animators make the bones' joints move according to the physical rules of the game's engine.
To effect breast movement in most 3D games, the breast's bones are equipped with "springs" that make the breasts bounce when the rest of the skeleton moves. The setup and strength of these springs determines the strength of the breast bounce. Alternatively, the motion of the breasts may be governed by custom-written software, but this is more time-consuming and therefore rarer than using springs, which are a built-in feature in many game engines.
Unnatural breast physics
Some video games feature breast movements that appear unnatural or exaggerated. This may result from limitations of the "springs" system, which is better suited to animating rigid bodies rather than soft objects like breasts. In some games, however, exaggerated breast physics are intentional. This may be caused by increasing the bounce effect in order to make it noticeable even when a character is standing still and talking, which may result in wildly exaggerated bounces when she actually moves.
Ultimately, however, according to game developer Tim Dawson, if a video game features unnatural breast movements, "it's because somebody wanted them to look that way". Not only female bodies but also male bodies are often intentionally exaggerated or unrealistically portrayed in video games.
Breast physics in individual games
Games noted for exaggerated breast physics
Games noted by video game publications for their exaggerated breast physics include the following:
Fatal Fury 2, fighting game (1992)
Mortal Kombat, fighting game series (1992–)
The King of Fighters, fighting game series (1994–)
Soulcalibur, fighting game series (1995–)
Dead or Alive, fighting game series (1996–). The bouncing was reduced in Dead or Alive 6, which uses a "natural" body physics engine.
Ready 2 Rumble Boxing, sports game (1999)
Conker's Bad Fur Day, platformer (2001), in which breasts are used as springboards
Lula 3D, adult adventure game (2005), which used motion capture and advertised "Bouncin' Boobs Technology" on its boxart.
Resident Evil, action game (2002/2015)
Ninja Gaiden Sigma 2, action game (2009), where the breasts' wobble can be separately controlled by the player
Skullgirls, fighting game (2012)
Lightning Returns: Final Fantasy XIII, role-playing game (2013)
Metal Gear Solid V: The Phantom Pain, action game (2015)
Games otherwise noted for their breast physics
Policenauts (PlayStation version in 1996): Hideo Kojima "will never forget arguing over the 'breast jiggle issue' with Shuhei Yoshida".
Fortnite Battle Royale (2017) used breast physics in a character model released in September 2018, which attracted controversy. The developer Epic Games later removed it as an "embarrassing and unintended" mistake.
Conan Exiles (2017) allows players to customize a female character's breast size or a male character's penis size. The size affects how much either piece of anatomy jiggles.
See also
Gender representation in video games
Sexism and video games
References
Further reading
Rogers, Ryan & Liebler, Carol. "Jubblies, mammaries and boobs: Discourses of breast physics in video games." Journal of Gaming & Virtual Worlds, Volume 9, Issue 3, September 2017, pp. 257-278. DOI: https://doi.org/10.1386/jgvw.9.3.257_1
Animation terminology
Breast
Video game terminology
Women and video games | Breast physics | [
"Technology"
] | 1,153 | [
"Computing terminology",
"Video game terminology"
] |
53,168,929 | https://en.wikipedia.org/wiki/Mike%20Payne%20%28physicist%29 | Michael Christopher Payne is a British theoretical physicist, working in the field of computational physics and theoretical condensed matter physics at the University of Cambridge.
He is the creator of first principles total energy pseudopotential code CASTEP and has been involved in the development of the linear scaling code ONETEP.
He was the 23rd most highly cited physical scientist in the UK between 1990 and 1999, and has published more than 250 papers which have had over 22,000 citations.
He studied at Pembroke College, Cambridge as an undergraduate and PhD student. He then spent a year in John Joannopoulos's group in the Massachusetts Institute of Technology before returning to Pembroke College as a research fellow, and to the Theory of Condensed Matter (TCM) group in the Cavendish Laboratory where he had earlier completed his PhD. He became a university lecturer in 1994, a reader in 1998 and a professor in 2000. In 2019 he became the first holder of the Ray Dolby Fellowship in Physics at Pembroke College.
He was awarded the 1996 Maxwell Medal and Prize by the Institute of Physics and gave the 1998 Mott Lecture. He was elected Fellow of the Royal Society in 2008 and awarded the Swan Medal and Prize by the Institute of Physics in 2014. In 2011 he was made an honorary fellow of the Institute of Physics.
He succeeded Peter Littlewood as head of the TCM group in the Cavendish Laboratory, a post he held until 2013 when he was succeeded by Benjamin Simons.
References
External links
Mike Payne, TCM, Cavendish Laboratory, University of Cambridge.
British theoretical physicists
Fellows of the Royal Society
Fellows of Pembroke College, Cambridge
Maxwell Medal and Prize recipients
Year of birth missing (living people)
Living people
Computational physicists | Mike Payne (physicist) | [
"Physics"
] | 339 | [
"Computational physicists",
"Computational physics"
] |
53,170,054 | https://en.wikipedia.org/wiki/The%20Second%20Forty%20Years | The Second Forty Years is a 1946 nonfiction self-help book about aging, by Edward Stieglitz.
Stieglitz graduated from Rush Medical College in 1921 and was on the faculty of the University of Chicago from 1923 to 1938. In 1940 a grant was given to support a gerontologist at the United States Public Health Service, and Stieglitz was given the post. His research was also supported by the National Institute of Health. Stieglitz left the post after a year, for personal reasons.
The Second Forty Years provides Stieglitz's professional advice for the layman. It describes what can be expected during the aging process and what can be done about it, discussing chronic progressive disorders which require preventative care, sex, the importance of leisure and rest, and so forth. According to Stieglitz, mere longevity is not goal enough, but rather constructive health practices should be undertaken to enhance the quality of life. Regarding menopause, Stieglitz characterized it as a "truly normal phase of living" and decried the "distorted descriptions" of old wives' tales.
Newspaper advertisements for The Second Forty Years are probably the source for the popular quotation "It's not the years in your life that count, it's the life in your years", which is commonly misattributed to Abraham Lincoln.
References
Further reading
1946 non-fiction books
Self-help books
Gerontology | The Second Forty Years | [
"Biology"
] | 289 | [
"Gerontology"
] |
53,170,829 | https://en.wikipedia.org/wiki/Stable%20isotope%20standards%20and%20capture%20by%20anti-peptide%20antibodies | Stable isotope standards and capture by anti-peptide antibodies (SISCAPA) is a mass spectrometry method for measuring the amount of a protein in a biological sample.
History
Introduced in 2004, the method has been used in a variety of studies in the field of proteomics, as well as in clinical blood tests in reference laboratories, and combines the advantageous features of mass spectrometry with those of conventional immunoassays. SISCAPA is used for measurement of specific pre-selected proteins and peptides (i.e., directed assays) rather than for broad exploration of sample contents (the typical objective of proteomics discovery or survey experiments).
Method
SISCAPA is an extension of the well-known gold-standard methods of stable-isotope dilution for quantitation of small molecules by mass spectrometry (MS). Rather than measure an intact protein directly by mass spectrometry, SISCAPA makes use of proteolytic digestion (e.g., with the enzyme trypsin) to cleave sample proteins into smaller peptides ideally suited to quantitation by mass spectrometry. By selecting a target peptide whose sequence occurs only in the selected target protein (a so-called “proteotypic” peptide), the target peptide can serve as a direct quantitative surrogate for the target protein (assuming the digestion process is complete, or at least reproducible). A synthetic version of the target peptide containing a stable isotope label is added in a known amount to the digested sample to serve as an internal standard (SIS). Since the target peptide and SIS are chemically indistinguishable throughout the workflow, but can be measured separately by a mass spectrometer due to the mass difference of the stable isotope label, their ratio provides the desired quantitative estimate of the target peptide amount.
The SISCAPA workflow adds a specific enrichment step to the isotope dilution method in which a selected target peptide, together with its associated SIS internal standard, is captured by a sequence-specific anti-peptide antibody. The antibody, together with the captured target peptide, is then separated from the complex sample digest, after which the highly purified peptide is eluted from the antibody and delivered to a mass spectrometer for measurement. The capture step has been implemented using antibodies bound to magnetic beads as well as antibodies immobilized on flow-through columns. Addition of this specific capture step provides two primary advantages in comparison with a conventional workflow analyzing an unfractionated sample digest: sensitivity and throughput.
The antibody can be used to capture the target peptide (and SIS) from a much larger mass of sample than could be analyzed directly by MS, thus allowing lower concentrations to be measured. In practice, assay sensitivity can be improved by 1,000-10,000-fold by this approach.
By removing the unbound (non-target) peptides present in the sample digest, the sample presented to the mass spectrometer is drastically simplified, thus reducing the need for peptide separation by liquid chromatography prior to MS analysis. In some cases liquid chromatography has been eliminated entirely, resulting in MS cycle times of 7-20 sec rather than 5–40 minutes required in typical unfractionated digest protocols involving extensive chromatographic separation.
By virtue of the extreme specificity of mass spectrometric detection, SISCAPA assays can be combined into multiplex panels without cross-assay interference. Panels combining 22, 50, and 150 assays into a single operation have been demonstrated.
SISCAPA’s use of proteolytic digestion as a first step eliminates the protein:protein complexes (including complexes of a target protein with auto-antibodies) that cause “interferences” in protein capture assays, including conventional immunoassays (e.g., ELISA assays). Elimination of such autoantibody interferences drove the adoption of SISCAPA as an alternative to immunoassays for clinical measurement of thyroglobulin as a marker of thyroid cancer recurrence in patients who exhibit anti-thyroglobulin autoantibodies.
A limitation of the specific peptide capture approach is the requirement for a specially-developed antibody against the selected peptide. To date several hundred anti-peptide antibody reagents have been developed for enrichment of tryptic peptides from sample digests, mainly for established clinical biomarkers (,) and cancer research targets, but these do not yet cover a majority of protein targets of interest in non-cancer research or clinical contexts.
A variety of MS instrument types have been used for quantitation of the enriched peptides, including most frequently triple quadrupole mass spectrometers implementing the “multiple reaction monitoring” (MRM) method (a format sometimes referred to as “immuno-MRM”), and MALDI-ToF (a format sometimes referred to as iMALDI).
Related methods
Alternative specific enrichment methods include MSIA (“mass spectrometric immunoassay”,) in which antibodies are used to enrich target proteins, which are analyzed intact by MS; and hybrid methods in which antibodies are used to enrich target proteins, which are then digested prior to peptide detection by MS.
References
Protein methods | Stable isotope standards and capture by anti-peptide antibodies | [
"Chemistry",
"Biology"
] | 1,101 | [
"Biochemistry methods",
"Protein methods",
"Protein biochemistry"
] |
42,985,529 | https://en.wikipedia.org/wiki/Paenibacterin | Paenibacterin is a mixture of antimicrobial lipopeptides isolated from Paenibacillus thiaminolyticus. It contains three isomeric compounds which differ by the fatty acid side chain.
References
Antimicrobial peptides
Lipopeptides
Paenibacillaceae | Paenibacterin | [
"Chemistry",
"Biology"
] | 64 | [
"Biotechnology stubs",
"Biochemistry stubs",
"Organic compounds",
"Biochemistry",
"Organic compound stubs",
"Organic chemistry stubs"
] |
42,985,608 | https://en.wikipedia.org/wiki/Cognitive%20biology | Cognitive biology is an emerging science that regards natural cognition as a biological function. It is based on the theoretical assumption that every organism—whether a single cell or multicellular—is continually engaged in systematic acts of cognition coupled with intentional behaviors, i.e., a sensory-motor coupling. That is to say, if an organism can sense stimuli in its environment and respond accordingly, it is cognitive. Any explanation of how natural cognition may manifest in an organism is constrained by the biological conditions in which its genes survive from one generation to the next. And since by Darwinian theory the species of every organism is evolving from a common root, three further elements of cognitive biology are required: (i) the study of cognition in one species of organism is useful, through contrast and comparison, to the study of another species' cognitive abilities; (ii) it is useful to proceed from organisms with simpler to those with more complex cognitive systems, and (iii) the greater the number and variety of species studied in this regard, the more we understand the nature of cognition.
Overview
While cognitive science endeavors to explain human thought and the conscious mind, the work of cognitive biology is focused on the most fundamental process of cognition for any organism. In the past several decades, biologists have investigated cognition in organisms large and small, both plant and animal. “Mounting evidence suggests that even bacteria grapple with problems long familiar to cognitive scientists, including: integrating information from multiple sensory channels to marshal an effective response to fluctuating conditions; making decisions under conditions of uncertainty; communicating with conspecifics and others (honestly and deceptively); and coordinating collective behaviour to increase the chances of survival.” Without thinking or perceiving as humans would have it, an act of basic cognition is arguably a simple step-by-step process through which an organism senses a stimulus, then finds an appropriate response in its repertoire and enacts the response. However, the biological details of such basic cognition have neither been delineated for a great many species nor sufficiently generalized to stimulate further investigation. This lack of detail is due to the lack of a science dedicated to the task of elucidating the cognitive ability common to all biological organisms. That is to say, a science of cognitive biology has yet to be established. A prolegomena for such science was presented in 2007 and several authors have published their thoughts on the subject since the late 1970s. Yet, as the examples in the next section suggest, there is neither consensus on the theory nor widespread application in practice.
Although the two terms are sometimes used synonymously, cognitive biology should not be confused with the biology of cognition in the sense that it is used by adherents to the Chilean School of Biology of Cognition. Also known as the Santiago School, the biology of cognition is based on the work of Francisco Varela and Humberto Maturana, who crafted the doctrine of autopoiesis. Their work began in 1970 while the first mention of cognitive biology by Brian Goodwin (discussed below) was in 1977 from a different perspective.
History
'Cognitive biology' first appeared in the literature as a paper with that title by Brian C. Goodwin in 1977. There and in several related publications Goodwin explained the advantage of cognitive biology in the context of his work on morphogenesis. He subsequently moved on to other issues of structure, form, and complexity with little further mention of cognitive biology. Without an advocate, Goodwin's concept of cognitive biology has yet to gain widespread acceptance.
Aside from an essay regarding Goodwin's conception by Margaret Boden in 1980, the next appearance of 'cognitive biology' as a phrase in the literature came in 1986 from a professor of biochemistry, Ladislav Kováč. His conception, based on natural principles grounded in bioenergetics and molecular biology, is briefly discussed below. Kováč's continued advocacy has had a greater influence in his homeland, Slovakia, than elsewhere partly because several of his most important papers were written and published only in Slovakian.
By the 1990s, breakthroughs in molecular, cell, evolutionary, and developmental biology generated a cornucopia of data-based theory relevant to cognition. Yet aside from the theorists already mentioned, no one was addressing cognitive biology except for Kováč.
Kováč's cognitive biology
Ladislav Kováč's “Introduction to cognitive biology” (Kováč, 1986a) lists ten 'Principles of Cognitive Biology.' A closely related thirty page paper was published the following year: “Overview: Bioenergetics between chemistry, genetics and physics.” (Kováč, 1987). Over the following decades, Kováč elaborated, updated, and expanded these themes in frequent publications, including "Fundamental principles of cognitive biology" (Kováč, 2000), “Life, chemistry, and cognition” (Kováč, 2006a), "Information and Knowledge in Biology: Time for Reappraisal” (Kováč, 2007) and "Bioenergetics: A key to brain and mind" (Kováč, 2008).
Academic usage
University seminar
The concept of cognitive biology is exemplified by this seminar description:
University workgroup
The University of Adelaide has established a "Cognitive Biology" workgroup using this operating concept:
Members of the group study the biological literature on simple organisms (e.g., nematode) in regard to cognitive process and look for homologues in more complex organisms (e.g., crow) already well studied. This comparative approach is expected to yield simple cognitive concepts common to all organisms. “It is hoped a theoretically well-grounded toolkit of basic cognitive concepts will facilitate the use and discussion of research carried out in different fields to increase understanding of two foundational issues: what cognition is and what cognition does in the biological context.” (Bold letters from original text.)
The group's choice of name, as they explain on a separate webpage, might have been 'embodied cognition' or 'biological cognitive science.' But the group chose 'cognitive biology' for the sake of (i) emphasis and (ii) method. For the sake of emphasis, (i) “We want to keep the focus on biology because for too long cognition was considered a function that could be almost entirely divorced from its physical instantiation, to the extent that whatever could be said of cognition almost by definition had to be applicable to both organisms and machines.” (ii) The method is to “assume (if only for the sake of enquiry) that cognition is a biological function similar to other biological functions—such as respiration, nutrient circulation, waste elimination, and so on.”
The method supposes that the genesis of cognition is biological, i.e., the method is biogenic. The host of the group's website has said elsewhere that cognitive biology requires a biogenic approach, having identified ten principles of biogenesis in an earlier work. The first four biogenic principles are quoted here to illustrate the depth at which the foundations have been set at the Adelaide school of cognitive biology:
“Complex cognitive capacities have evolved from simpler forms of cognition. There is a continuous line of meaningful descent.”
“Cognition directly or indirectly modulates the physico-chemical-electrical processes that constitute an organism .”
“Cognition enables the establishment of reciprocal causal relations with an environment, leading to exchanges of matter and energy that are essential to the organism's continued persistence, well-being or replication.”
“Cognition relates to the (more or less) continuous assessment of system needs relative to prevailing circumstances, the potential for interaction, and whether the current interaction is working or not.”
Other universities
As another example, the Department für Kognitionsbiologie at the University of Vienna declares in its mission statement a strong commitment “to experimental evaluation of multiple, testable hypotheses” regarding cognition in terms of evolutionary and developmental history as well as adaptive function and mechanism, whether the mechanism is cognitive, neural, and/or hormonal. “The approach is strongly comparative: multiple species are studied, and compared within a rigorous phylogenetic framework, to understand the evolutionary history and adaptive function of cognitive mechanisms ('cognitive phylogenetics').” Their website offers a sample of their work: “Social Cognition and the Evolution of Language: Constructing Cognitive Phylogenies.”
A more restricted example can be found with the Cognitive Biology Group, Institute of Biology, Faculty of Science, Otto-von-Guericke University (OVGU) in Magdeburg, Germany. The group offers courses titled “Neurobiology of Consciousness” and “Cognitive Neurobiology.” Its website lists the papers generated from its lab work, focusing on the neural correlates of perceptual consequences and visual attention. The group's current work is aimed at detailing a dynamic known as 'multistable perception.' The phenomenon, described in a sentence: “Certain visual displays are not perceived in a stable way but, from time to time and seemingly spontaneously, their appearance wavers and settles in a distinctly different form.”
A final example of university commitment to cognitive biology can be found at Comenius University in Bratislava, Slovakia. There in the Faculty of Natural Sciences, the Bratislava Biocenter is presented as a consortium of research teams working in biomedical sciences. Their website lists the Center for Cognitive Biology in the Department of Biochemistry at the top of the page, followed by five lab groups, each at a separate department of bioscience. The webpage for the Center for Cognitive Biology offers a link to "Foundations of Cognitive Biology," a page that simply contains a quotation from a paper authored by Ladislav Kováč, the site's founder. His perspective is briefly discussed below.
Cognitive biology as a category
The words 'cognitive' and 'biology' are also used together as the name of a category. The category of cognitive biology has no fixed content but, rather, the content varies with the user. If the content can only be recruited from cognitive science, then cognitive biology would seem limited to a selection of items in the main set of sciences included by the interdisciplinary concept—cognitive psychology, artificial intelligence, linguistics, philosophy, neuroscience, and cognitive anthropology. These six separate sciences were allied “to bridge the gap between brain and mind” with an interdisciplinary approach in the mid-1970s. Participating scientists were concerned only with human cognition. As it gained momentum, the growth of cognitive science in subsequent decades seemed to offer a big tent to a variety of researchers. Some, for example, considered evolutionary epistemology a fellow-traveler. Others appropriated the keyword, as for example Donald Griffin in 1978, when he advocated the establishment of cognitive ethology.
Meanwhile, breakthroughs in molecular, cell, evolutionary, and developmental biology generated a cornucopia of data-based theory relevant to cognition. Categorical assignments were problematic. For example, the decision to append cognitive to a body of biological research on neurons, e.g. the cognitive biology of neuroscience, is separate from the decision to put such body of research in a category named cognitive sciences. No less difficult a decision needs be made—between the computational and constructivist approach to cognition, and the concomitant issue of simulated v. embodied cognitive models—before appending biology to a body of cognitive research, e.g. the cognitive science of artificial life.
One solution is to consider cognitive biology only as a subset of cognitive science. For example, a major publisher's website displays links to material in a dozen domains of major scientific endeavor. One of which is described thus: “Cognitive science is the study of how the mind works, addressing cognitive functions such as perception and action, memory and learning, reasoning and problem solving, decision-making and consciousness.” Upon its selection from the display, the Cognitive Science page offers in nearly alphabetical order these topics: Cognitive Biology, Computer Science, Economics, Linguistics, Psychology, Philosophy, and Neuroscience. Linked through that list of topics, upon its selection the Cognitive Biology page offers a selection of reviews and articles with biological content ranging from cognitive ethology through evolutionary epistemology; cognition and art; evo-devo and cognitive science; animal learning; genes and cognition; cognition and animal welfare; etc.
A different application of the cognitive biology category is manifest in the 2009 publication of papers presented at a three-day interdisciplinary workshop on “The New Cognitive Sciences” held at the Konrad Lorenz Institute for Evolution and Cognition Research in 2006. The papers were listed under four headings, each representing a different domain of requisite cognitive ability: (i) space, (ii) qualities and objects, (iii) numbers and probabilities, and (iv) social entities. The workshop papers examined topics ranging from “Animals as Natural Geometers” and “Color Generalization by Birds” through “Evolutionary Biology of Limited Attention” and “A comparative Perspective on the Origin of Numerical Thinking” as well as “Neuroethology of Attention in Primates” and ten more with less colorful titles. “[O]n the last day of the workshop the participants agreed [that] the title 'Cognitive Biology' sounded like a potential candidate to capture the merging of the cognitive and the life sciences that the workshop aimed at representing.” Thus the publication of Tommasi, et al. (2009), Cognitive Biology: Evolutionary and Developmental Perspectives on Mind, Brain and Behavior.
A final example of categorical use comes from an author's introduction to his 2011 publication on the subject, Cognitive Biology: Dealing with Information from Bacteria to Minds. After discussing the differences between the cognitive and biological sciences, as well as the value of one to the other, the author concludes: “Thus, the object of this book should be considered as an attempt at building a new discipline, that of cognitive biology, which endeavors to bridge these two domains.” There follows a detailed methodology illustrated by examples in biology anchored by concepts from cybernetics (e.g., self-regulatory systems) and quantum information theory (regarding probabilistic changes of state) with an invitation "to consider system theory together with information theory as the formal tools that may ground biology and cognition as traditional mathematics grounds physics.”
See also
Biosemiotics
Cognitive anthropology
Cognitive science of religion
Cognitive neuropsychology
Cognitive neuroscience
Cognitive psychology
Cognitive science
Embodied cognitive science
Embodied cognition
Evolutionary epistemology
Naturalized epistemology
Neuroepistemology
Spatial cognition
References & notes
Bibliography
Auletta, Gennaro (2011). Cognitive biology: dealing with information from bacteria to minds. Oxford University Press.
Baluška, František and Stefano Mancuso (2009). Deep evolutionary origins of neurobiology: Turning the essence of 'neural' upside-down. Commun Integr Biol. Jan-Feb; 2(1): 60–65.
Bechtel, William (2013). Seminar description for "Cognitive Biology" in the "Cognitive Science 200" series for "Fall, 2013" at University of California, San Diego, <http://mechanism.ucsd.edu/teaching/f13/cs200/>. See also http://mechanism.ucsd.edu/teaching/f13/cs200/bacterialinformationprocessing.pdf.
Ben Jacob, Eshel, Yoash Shapira, and Alfred I. Tauber (2006). "Seeking the foundations of cognition in bacteria: From Schrödinger's negative entropy to latent information." Physica A: Statistical Mechanics and its Applications 359: 495-524.
Bird, Angela (2010). Review - Cognitive Biology: Evolutionary and Developmental Perspectives on Mind, Brain, and Behavior
by Luca, Tommasi, Mary A. Peterson and Lynn Nadel (Editors, MIT Press, 2009). Metapsychology Online Reviews, Volume 14, Issue 3.
Boden, Margaret A (2006). Mind as machine: A history of cognitive science. Vol. 1. Oxford University Press.
Boden, Margaret and Susan K Zaw (1980). “The case for a cognitive biology.” Proceedings of the Aristotelian Society, 54: 25–71.
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Calvo, Paco, and Fred Keijzer (2009). "Cognition in plants." Plant-environment interactions: Signaling & communication in plants: 247-266.
Chomsky, N. (1972). Problems of Knowledge and Freedom. London: Fontana.
Denton, Michael J., Craig J. Marshall, and Michael Legge (2002). "The protein folds as platonic forms: new support for the pre-Darwinian conception of evolution by natural law." Journal of Theoretical Biology 219.3: 325-342.
Emmeche, Claus. "Life as an abstract phenomenon: Is artificial life possible?" (1992). Pages 466-474 in Francisco J. Varela and Paul Bourgine (eds.):Toward a Practice of Autonomous Systems. Proceedings of the First European Conference on Artificial Life. The MIT Press.
Frankish, Keith, and William Ramsey, editors (2012). The Cambridge Handbook of Cognitive Science. Cambridge University Press.
Goodwin, Brian C (1976a). Analytical Physiology of Cells and Developing Organisms. London: Academic Press.
Goodwin, Brian C (1976b). "On some relationships between embryogenesis and cognition." Theoria to Theory 10: 33-44.
Goodwin, Brian C (1977). "Cognitive biology." Communication & Cognition. Vol 10(2), 87-91. This paper also appeared the same year in deMey, M, R. Pinxten, M. Poriau & F. Vandamme (Eds.), CC77 International Workshop on the Cognitive Viewpoint, University of Ghent Press, London, pp. 396–400.
Goodwin, Brian C (1978). “A cognitive view of biological process.” J Soc Biol Structures 1:117-125
Griffin, Donald R. "Prospects for a cognitive ethology." Behavioral and Brain Sciences 1.04 (1978): 527-538.
Huber, Ludwig and Anna Wilkinson. "Evolution of cognition: A comparative approach." Chapter 8 in Sensory Perception. Springer Vienna, 2012. 135-152.
Kamil, Alan C. (1998). "On the proper definition of cognitive ethology." Animal cognition in nature. Academic Press, San Diego 1-28.
Kováč, Ladislav (1986a). “Úvod do kognitívnej biológie.” (Published in Slovak with an abstract in English, the title translates as an “Introduction to cognitive biology.”) Biol. listy 51: 172- 190. {Since old copies of Biologické listy are hard to find, see Kováč (2004a) for the republished version which is also in Slovak. Google translates it into English well enough, with some help from the reader using the Google translation tool.}
Kováč, Ladislav (1986b). The future of bioenergetics. EBEC Reports 4: 26 - 27.
Kováč, Ladislav (1987). “Overview: Bioenergetics between chemistry, genetics and physics.” Curr. Topics Bioenerg. 15: 331- 372.
Kováč, Ladislav (2000). "Fundamental principles of cognitive biology." Evolution and cognition 6.1: 51-69. Evolution and Cognition was published by the Konrad Lorenz Institute for Evolution and Cognition Research (KLI) from 1995-2004. That journal was succeeded by a journal titled Biological Theory: Integrating Development, Evolution and Cognition. The paper is archived at this URL < http://www.biocenter.sk/lkpublics_files/C-7.pdf >.
Kováč, Ladislav (2006a). “Life, chemistry, and cognition.” EMBO Reports 7, 562- 566
Kováč, Ladislav (2006b) “Princípy molekulárnej kognície.” Kognice an umělý život VI : 215-222. Translation: “Principles of Molecular Cognition.” Cognition and Artificial Life VI: pp. 215–222
Kovác, Ladislav (2007). "Information and Knowledge in Biology: Time for Reappraisal.” Plant Signaling & Behavior 2:2, 65-73
Kovác, Ladislav (2008). "Bioenergetics: A key to brain and mind." Communicative & integrative biology 1.1: 114-122.
Lyon, Pamela (2006), 'The biogenic approach to cognition', Cognitive Processing 7(1), 11–29.
Lyon, Pamela (2013a). Foundations for a Cognitive Biology. Published on the homepage of the Cognitive Biology Project at the University of Adelaide. https://web.archive.org/web/20141018181532/http://www.hss.adelaide.edu.au/philosophy/cogbio/
Lyon, Pamela (2013b). Why Cognitive Biology? Published on an HTML page linked to Lyon (2013a). https://web.archive.org/web/20140714230036/http://www.hss.adelaide.edu.au/philosophy/cogbio/why/
Lyon, Pamela C and Jonathan P Opie (2007). “Prolegomena for a cognitive biology.” A conference paper presented at the Proceedings of the 2007 Meeting of International Society for the History, Philosophy and Social Studies of Biology, University of Exeter. Abstract at http://hdl.handle.net/2440/46578.
Lyon, Pamela, and Fred Keijzer (2007). "The human stain." Pages 132-165 in Wallace, Brendan editor. The mind, the body, and the world: psychology after cognitivism?. Imprint Academic, 2007
Mandler, George (2002). "Origins of the cognitive (r)evolution". Journal of the History of the Behavioral Sciences 38 (4): 339–353. doi:10.1002/jhbs.10066..
Margolis, Eric, Richard Samuels, and Stephen P. Stich, editors (2012). The Oxford Handbook of Philosophy of Cognitive Science. Oxford University Press.
Maturana, Humberto R. (1970). “Biology of Cognition.” Biological Computer Laboratory Research Report BCL 9.0. Urbana IL: University of Illinois. Reprinted in: Autopoiesis and Cognition: The Realization of the Living. Dordecht: D. Reidel Publishing Co., 1980, pp. 5–58.
Miller, George A. "The cognitive revolution: a historical perspective." Trends in cognitive sciences 7.3 (2003): 141-144.
Prigogine, Ilya (1980). From Being to Becoming. Freeman, San Francisco.
Shapiro, J.A. (2007). “Bacteria are small but not stupid: cognition, natural genetic engineering and socio-bacteriology.” Stud. Hist. Phil. Biol. & Biomed. Sci., Vol. 38: 807–819.
Shapiro, J.A. (2011). Evolution: A View from the 21st Century, FT Press Science, NJ, USA.
Spetch, Marcia L., and Alinda Friedman (2006). "Comparative cognition of object recognition." Comparative Cognition & Behavior Reviews 1: 12-35.
Spitzer, Jan, and Bert Poolman (2009). "The role of biomacromolecular crowding, ionic strength, and physicochemical gradients in the complexities of life's emergence." Microbiology and Molecular Biology Reviews 73.2: 371-388.
Stahlberg, Rainer (2006) “Historical Overview on Plant Neurobiology.” Plant Signaling & Behavior 1:1, 6-8.
Stotz, Karola, and Colin Allen. "From cell-surface receptors to higher learning: A whole world of experience." In Philosophy of behavioral
biology, pp. 85–123. Springer Netherlands, 2012.
Tommasi, Luca, Mary A. Peterson, and Lynn Nadel, eds. (2009). Cognitive Biology: Evolutionary and Developmental Perspectives on Mind, Brain and Behavior. The MIT Press.
Tinbergen, N. (1963). On aims and methods in ethology. Zeitschrift für Tierpsychologie, 20, 410-433.
Van Duijn, Marc, Fred Keijzer, and Daan Franken. "Principles of minimal cognition: Casting cognition as sensorimotor coordination." Adaptive Behavior14.2 (2006): 157-170.
Von Eckardt, Barbara. What is cognitive science?. MIT press, 1995.
Wasserman, Edward A. (1993). "Comparative cognition: Beginning the second century of the study of animal intelligence." Psychological Bulletin 113.2: 211
Webster, Gerry, and Brian C. Goodwin (1982). "The origin of species: a structuralist approach." Journal of Social and Biological Structures 5.1: 15-47.
Webster, Gerry, and Brian Goodwin (1996). Form and transformation: generative and relational principles in biology. Cambridge University Press.
Whitehead, Alfred North. (1929). Process and Reality. Cambridge University Press.
WIRES (Wiley Interdisciplinary Reviews) http://wires.wiley.com/WileyCDA/ (2013). Wiley Online Library. John Wiley & Sons, Inc.
Zentall, Thomas R., Edward A. Wasserman, Olga F. Lazareva, Roger KR Thompson, and Mary Jo Rattermann (2008). "Concept learning in animals." Comp Cogn Behav Rev 3: 13-45.
External links
European Network for the Advancement of Artificial Cognitive Systems, Interaction and Robotics
Comparative Cognition and Behavior Reviews
Ladislav Kováč's Publications
Cognition
Branches of biology
Branches of cognitive science
Cognitive psychology
Plant intelligence | Cognitive biology | [
"Biology"
] | 5,453 | [
"Behavior",
"Plants",
"Plant intelligence",
"Behavioural sciences",
"nan",
"Cognitive psychology"
] |
42,987,364 | https://en.wikipedia.org/wiki/Bott%E2%80%93Samelson%20resolution | In algebraic geometry, the Bott–Samelson resolution of a Schubert variety is a resolution of singularities. It was introduced by in the context of compact Lie groups. The algebraic formulation is independently due to and .
Definition
Let G be a connected reductive complex algebraic group, B a Borel subgroup and T a maximal torus contained in B.
Let Any such w can be written as a product of reflections by simple roots. Fix minimal such an expression:
so that . (ℓ is the length of w.) Let be the subgroup generated by B and a representative of . Let be the quotient:
with respect to the action of by
It is a smooth projective variety. Writing for the Schubert variety for w, the multiplication map
is a resolution of singularities called the Bott–Samelson resolution. has the property: and In other words, has rational singularities.
There are also some other constructions; see, for example, .
Notes
References
.
.
.
.
.
.
Algebraic geometry
Singularity theory | Bott–Samelson resolution | [
"Mathematics"
] | 206 | [
"Fields of abstract algebra",
"Algebraic geometry"
] |
42,989,113 | https://en.wikipedia.org/wiki/Austroboletus%20eburneus | Austroboletus eburneus is a species of bolete fungus found in Australia. It was described as new to science in 1986. The species name eburneus is the Latin adjective "ivory-white".
References
External links
eburneus
Fungi described in 1986
Fungi native to Australia
Taxa named by Roy Watling
Fungus species | Austroboletus eburneus | [
"Biology"
] | 68 | [
"Fungi",
"Fungus species"
] |
42,989,297 | https://en.wikipedia.org/wiki/Carina%20OB1 | Carina OB1 is a giant OB association in the Carina Nebula, which is home to some of the most massive and luminous stars in the Milky Way Galaxy. It includes the young star clusters Collinder 228, NGC 3293, NGC 3324, IC 2581, Trumpler 14, Trumpler 15 and Trumpler 16, the last being the home of Eta Carinae. It also includes another massive and luminous star, HD 93129A. It is approximately from Earth.
It is one of the largest known stellar associations, along with Sagittarius OB5 and Cygnus OB2. It is much easier to see than that of the other associations since Carina OB1 has relatively little dust extinction in its region. Together with Carina OB2, they compromise the most massive stellar grouping known in the galaxy.
Carina OB1 is about across, and is the most massive stellar association in the Milky Way Galaxy since it lies within an active emission nebula. It contains many hot luminous stars which share common characteristics.
References
Carina Nebula
Stellar associations
Carina (constellation) | Carina OB1 | [
"Astronomy"
] | 221 | [
"Carina (constellation)",
"Constellations"
] |
42,989,614 | https://en.wikipedia.org/wiki/Laplace%20equation%20for%20irrotational%20flow | Irrotational flow occurs where the curl of the velocity of the fluid is zero everywhere. That is when
Similarly, if it is assumed that the fluid is incompressible:
Then, starting with the continuity equation:
The condition of incompressibility means that the time derivative of the density is 0, and that the density can be pulled out of the divergence, and divided out, thus leaving the continuity equation for an incompressible system:
Now, the Helmholtz decomposition can be used to write the velocity as the sum of the gradient of a scalar potential and as the curl of a vector potential. That is:
Note that imposing the condition that implies that
The curl of the gradient is always 0. Note that the curl of the curl of a function is only uniformly 0 for the vector potential being 0 itself. So, by the condition of irrotational flow:
And then using the continuity equation , the scalar potential can be substituted back in to find Laplace's Equation for irrotational flow:
Note that the Laplace equation is a well-studied linear partial differential equation. Its solutions are infinite; however, most solutions can be discarded when considering physical systems, as boundary conditions completely determine the velocity potential.
Examples of common boundary conditions include the velocity of the fluid, determined by , being 0 on the boundaries of the system.
There is a great amount of overlap with electromagnetism when solving this equation in general, as the Laplace equation also models the electrostatic potential in a vacuum.
There are many reasons to study irrotational flow, among them;
Many real-world problems contain large regions of irrotational flow.
It can be studied analytically.
It shows us the importance of boundary layers and viscous forces.
It provides us tools for studying concepts of lift and drag.
See also
Irrotational vector fields
Irrotational vortices
Potential flow around a circular cylinder
Potential flow around an airfoil section
References
Fluid dynamics | Laplace equation for irrotational flow | [
"Chemistry",
"Engineering"
] | 406 | [
"Piping",
"Chemical engineering",
"Fluid dynamics"
] |
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