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Rodrigues
Rodrigues (French: Île Rodrigues [il ʁɔdʁiɡ]; Creole: Rodrig) is a 108 km2 (42 sq mi) autonomous outer island of the Republic of Mauritius in the Indian Ocean, about 560 km (350 mi) east of Mauritius. It is part of the Mascarene Islands, which include Mauritius and Réunion. Rodrigues is of volcanic origin and is surrounded by coral reef, and some tiny uninhabited islands lie just off its coast. The island used to be the tenth District of Mauritius; it gained autonomous status on 10 December 2002, and it is governed by the Rodrigues Regional Assembly. The capital of the island is Port Mathurin. Its inhabitants are Mauritian citizens. (As of 2014), the island's population was about 41,669, according to Statistics Mauritius. Most of the inhabitants are of African descent. Its economy is based mainly on fishing, farming, handicraft and a developing tourism sector. The island (together with Agaléga and Saint Brandon) forms part of the larger territory of the Republic of Mauritius with the President as head of state and the Chief Commissioner as head of government.
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  • 11 Nov 2022
Topic Review
List of Meteor Air Bursts
Many explosions recorded in Earth's atmosphere are likely to be caused by the air bursts that result from meteors exploding as they hit the thicker part of the atmosphere. These types of meteors are also known as fireballs or bolides with the brightest known as superbolides. Before entering Earth's atmosphere, these larger meteors were originally asteroids and comets of a few to several tens of metres in diameter, contrasting with the much smaller and much more common "shooting stars". The most powerful recorded air burst is the 1908 Tunguska event. Extremely bright fireballs traveling across the sky are often witnessed from a distance, such as the 1947 Sikhote-Alin meteor and the 2013 Chelyabinsk meteor, both in Russia. If the bolide is large enough, fragments may survive such as the Chelyabinsk meteorite. Modern developments in infrasound detection by the Comprehensive Nuclear-Test-Ban Treaty Organization and infrared Defense Support Program satellite technology have increased the likelihood of detecting airbursts.
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  • 11 Nov 2022
Topic Review
Copernicus Programme
Copernicus is the European Union's Earth observation programme coordinated and managed by the European Commission in partnership with the European Space Agency (ESA), the EU Member States and EU Agencies. It aims at achieving a global, continuous, autonomous, high quality, wide range Earth observation capacity. Providing accurate, timely and easily accessible information to, among other things, improve the management of the environment, understand and mitigate the effects of climate change, and ensure civil security. The objective is to use vast amount of global data from satellites and from ground-based, airborne and seaborne measurement systems to produce timely and quality information, services and knowledge, and to provide autonomous and independent access to information in the domains of environment and security on a global level in order to help service providers, public authorities and other international organizations improve the quality of life for the citizens of Europe. In other words, it pulls together all the information obtained by the Copernicus environmental satellites, air and ground stations and sensors to provide a comprehensive picture of the "health" of Earth. One of the benefits of the Copernicus Programme is that the data and information produced in the framework of Copernicus are made available free-of-charge to all its users and the public, thus allowing downstream services to be developed. The services offered by Copernicus cover six main interacting themes: atmosphere, marine, land, climate, emergency and security. Copernicus builds upon three components: Its cost during 1998 to 2020 are estimated at 6.7 billion euros with around €4.3bn spent in the period 2014 to 2020 and shared between the EU (66%) and ESA (33%) with benefits of the data to the EU economy estimated at roughly 30 billion euros through 2030. ESA as a main partner has performed much of the design and oversees and co-funds the development of Sentinel missions 1, 2, 3, 4, 5 and 6 with each Sentinel mission consisting of at least 2 satellites and some, such as Sentinel 1, consisting of 4 satellites. They will also provide the instruments for Meteosat Third Generation and MetOp-SG weather satellites of EUMETSAT where ESA and EUMETSAT will also coordinate the delivery of data from upwards of 30 satellites that form the contributing satellite missions to Copernicus.
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Topic Review
Universal Priesthood
The universal priesthood or the priesthood of all believers is a principle in some branches of Christianity which abrogates the doctrine of holy orders found in some other branches, including the Roman Catholic and Eastern Orthodox. Derived from the Bible and elaborated in the theology of Martin Luther and John Calvin, the principle became prominent as a tenet of Protestant Christian doctrine, though the exact meaning of the belief and its implications vary widely among denominations.
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Topic Review
Photometry
Photometry, from Greek photo- ("light") and -metry ("measure"), is a technique used in astronomy that is concerned with measuring the flux or intensity of light radiated by astronomical objects. This light is measured through a telescope using a photometer, often made using electronic devices such as a CCD photometer or a photoelectric photometer that converts light into an electric current by the photoelectric effect. When calibrated against standard stars (or other light sources) of known intensity and colour, photometers can measure the brightness or apparent magnitude of celestial objects. The methods used to perform photometry depend on the wavelength region under study. At its most basic, photometry is conducted by gathering light and passing it through specialized photometric optical bandpass filters, and then capturing and recording the light energy with a photosensitive instrument. Standard sets of passbands (called a photometric system) are defined to allow accurate comparison of observations. A more advanced technique is spectrophotometry that is measured with a spectrophotometer and observes both the amount of radiation and its detailed spectral distribution. Photometry is also used in the observation of variable stars, by various techniques such as, differential photometry that simultaneously measures the brightness of a target object and nearby stars in the starfield or relative photometry by comparing the brightness of the target object to stars with known fixed magnitudes. Using multiple bandpass filters with relative photometry is termed absolute photometry. A plot of magnitude against time produces a light curve, yielding considerable information about the physical process causing the brightness changes. Precision photoelectric photometers can measure starlight around 0.001 magnitude. The technique of surface photometry can also be used with extended objects like planets, comets, nebulae or galaxies that measures the apparent magnitude in terms of magnitudes per square arcsecond. Knowing the area of the object and the average intensity of light across the astronomical object determines the surface brightness in terms of magnitudes per square arcsecond, while integrating the total light of the extended object can then calculate brightness in terms of its total magnitude, energy output or luminosity per unit surface area.
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Topic Review
Smallpox Vaccine
The smallpox vaccine is the first vaccine to be developed against a contagious disease. In 1796, the British doctor Edward Jenner demonstrated that an infection with the relatively mild cowpox virus conferred immunity against the deadly smallpox virus. Cowpox served as a natural vaccine until the modern smallpox vaccine emerged in the 20th century. From 1958 to 1977, the World Health Organization (WHO) conducted a global vaccination campaign that eradicated smallpox, making it the only human disease to be eradicated. Although routine smallpox vaccination is no longer performed on the general public, the vaccine is still being produced to guard against bioterrorism, biological warfare, and monkeypox. The term vaccine derives from the Latin word for cow, reflecting the origins of smallpox vaccination. Edward Jenner referred to cowpox as variolae vaccinae (smallpox of the cow). The origins of the smallpox vaccine became murky over time, especially after Louis Pasteur developed laboratory techniques for creating vaccines in the 19th century. Allan Watt Downie demonstrated in 1939 that the modern smallpox vaccine was serologically distinct from cowpox, and vaccinia was subsequently recognized as a separate viral species. Whole-genome sequencing has revealed that vaccinia is most closely related to horsepox, and the cowpox strains found in Great Britain are the least closely related to vaccinia.
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  • 14 Apr 2023
Topic Review
Hematopoietic Stem Cell Transplant
Hematopoietic stem cell transplantation (HSCT) or Bone marrow transplantation is a medical procedure in the field of hematology and oncology that involves transplantation of hematopoietic stem cells (HSC). It is most often performed for people with diseases of the blood or bone marrow, or certain types of cancer. Bone marrow transplantation was pioneered at the Fred Hutchinson Cancer Research Center from the 1950s through the 1970s by E. Donnall Thomas, whose work was later recognized with a Nobel Prize in Physiology and Medicine. Dr. Thomas' work showed that bone marrow cells infused intravenously could repopulate the bone marrow and produce new blood cells. His work also reduced the likelihood of developing a life-threatening complication called Graft-versus-host disease. Since the early 1990s and the availability of the stem cell growth factors GM-CSF and G-CSF, most hematopoeitic stem cell transplantation procedures have been performed with stem cells collected from the peripheral blood. Collecting stem cells provides a bigger graft, and does not require that the donor be subjected to general anesthesia to collect the graft. Hematopoeitic stem cell transplantation remains a risky procedure and has always been reserved for patients with life threatening diseases.
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Topic Review
Unemployment Benefits
Unemployment benefits (depending on the jurisdiction also called unemployment insurance or unemployment compensation) are payments made by back authorized bodies to unemployed people. In the United States, benefits are funded by a compulsory governmental insurance system, not taxes on individual citizens. Depending on the jurisdiction and the status of the person, those sums may be small, covering only basic needs, or may compensate the lost time proportionally to the previous earned salary. Unemployment benefits are generally given only to those registering as unemployed, and often on conditions ensuring that they seek work and do not currently have a job, and are validated as being laid off and not fired for cause in most states.
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  • 11 Nov 2022
Topic Review
Pseudohermaphroditism
Pseudohermaphroditism (also spelled pseudo-hermaphroditism) is an old clinical term for an organism that is born with primary sex characteristics of one sex but develops the secondary sex characteristics that are different from what would be expected on the basis of the gonadal tissue (ovary or testis). It can be contrasted with the term true hermaphroditism, which described a condition where testicular and ovarian tissue were present in the same individual. This language has fallen out of favor due to misconceptions and pejorative connotations associated with the terms, and also a shift to nomenclature based on genetics. The term male pseudo-hermaphrodite was used when a testis is present, and the term female pseudo-hermaphrodite was used when an ovary is present. In some cases, external sex organs associated with pseudohermaphroditism look intermediate between a typical clitoris and penis. In other cases, the external sex organs have an appearance that would be expected to be seen with the "opposite" gonadal tissue. Because of this, pseudohermaphroditism is sometimes not identified until puberty or adulthood. Associated conditions include 5-α-reductase deficiency and androgen insensitivity syndrome.
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  • 16 Nov 2022
Topic Review
Novichok Agent
A Novichok agent (Russian: Новичо́к, "newcomer", "novice", "newbie") is a group of nerve agents, some of which are binary chemical weapons. The agents were developed at the GosNIIOKhT state chemical research institute by the Soviet Union and Russia between 1971 and 1993.[lower-alpha 1] Some Novichok agents at STP are solids while others are liquids. It is thought that dispersal for the solids is possible by ultrafine powder. Russian scientists who developed the nerve agents claim they are the deadliest ever made, with some variants possibly five to eight times more potent than VX, and others up to ten times more potent than soman. As well as Russia, Novichok agents have been known to be produced in Iran. In the 21st century, Novichok agents came to public attention after they were used to poison opponents of the Russian government, including the Skripals and two others in Amesbury, UK (2018) and Alexei Navalny (2020), but civil poisonings with this substance have been known since at least 1995. In November 2019, the Organisation for the Prohibition of Chemical Weapons (OPCW), which is the executive body for the Chemical Weapons Convention (CWC), added the Novichok agents to "list of controlled substances" of the CWC "in one of the first major changes to the treaty since it was agreed in the 1990s" in response to the 2018 poisonings in the UK.
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