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Clostridioides Difficile (Bacteria)
Clostridioides difficile (syn. Clostridium difficile), also known as C. difficile, or C. diff (/siː dɪf/), is Gram-positive species of spore-forming bacteria. Clostridioides spp. are anaerobic, motile bacteria, ubiquitous in nature and especially prevalent in soil. Its vegetative cells are rod-shaped, pleomorphic, and occur in pairs or short chains. Under the microscope, they appear as long, irregular (often drumstick- or spindle-shaped) cells with a bulge at their terminal ends (forms subterminal spores). Under Gram staining, C. difficile cells are Gram-positive and show optimum growth on blood agar at human body temperatures in the absence of oxygen. C. difficile is catalase- and superoxide dismutase-negative, and produces up to three types of toxins: enterotoxin A, cytotoxin B and Cytolethal distending toxin. Under stress conditions, the bacteria produce spores that are able to tolerate extreme conditions that the active bacteria cannot tolerate. Clostridioides difficile is an important emerging human pathogen; according to the CDC, in 2017 there were 223,900 cases in hospitalized patients and 12,800 deaths in the United States. Although C. difficile is commonly known as a hospital and antibiotic associated pathogen, at most one third of infections can be traced to transmission from an infected person in hospitals, and only a small number of antibiotics are directly associated with an elevated risk of developing a C. difficile infection (CDI), namely clindamycin, fluoroquinolones and cephalosporins. The majority of infections are acquired outside of hospitals, and most antibiotics have similar elevated risk of infection on par with many non-antibiotic risk factors, such as using stool softeners and receiving an enema. Clostridioides difficile can also become established in the human colon without causing disease. Although early estimates indicated that C. difficile was present in 2–5% of the adult population, more recent research indicates colonization is closely associated with a history of unrelated diarrheal illnesses, such as food poisoning or laxative abuse. Individuals with no history of gastrointestinal disturbances appear unlikely to become asymptomatic carriers. These carriers are thought to be a major reservoir of infection.
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  • 24 Oct 2022
Topic Review
Gargoyle
In architecture, a gargoyle (/ˈɡɑːrɡɔɪl/) is a carved or formed grotesque:6–8 with a spout designed to convey water from a roof and away from the side of a building, thereby preventing rainwater from running down masonry walls and eroding the mortar between. Architects often used multiple gargoyles on a building to divide the flow of rainwater off the roof to minimize the potential damage from a rainstorm. A trough is cut in the back of the gargoyle and rainwater typically exits through the open mouth. Gargoyles are usually an elongated fantastical animal because the length of the gargoyle determines how far water is directed from the wall. When Gothic flying buttresses were used, aqueducts were sometimes cut into the buttress to divert water over the aisle walls.
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  • 24 Oct 2022
Topic Review
IBM Microfilm Products
IBM manufactured and sold microfilm products from 1963 till 1969. It is an example of IBM attempting to enter an established market on the basis of a significant technical breakthrough.
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  • 24 Oct 2022
Topic Review
Meat Analogue
A meat analogue is a food industry term for a meat-like substance made from vegetarian ingredients. More common terms are plant-based meat, vegan meat, meat substitute, mock meat, meat alternative, imitation meat, or vegetarian meat, or, sometimes more pejoratively, fake meat or faux meat. Meat analogues typically approximate certain aesthetic qualities (such as texture, flavor, appearance) or chemical characteristics of specific types of meat. Many analogues are soy-based (e.g., tofu, tempeh) or gluten-based but now may also be made from pea protein. Other less common analogues include cottage cheese and mycoprotein. Because of their similarity to meats, they are frequently used in dishes and food practices similar to meat. The target market for meat analogues includes vegetarians, vegans, non-vegetarians seeking to reduce their meat consumption, and people following religious dietary laws in Hinduism, Judaism, Islam, Christian vegetarianism, and Buddhism. Increasingly, the global demand for sustainable diets in response to the outsized role animal products play in global warming and other environmental impacts has seen an increase in industries focused on finding substitutes similar to meat. However, the motivation for seeking out mock meats tends to vary depending on consumer group. The market for meat alternatives is highly dependent on "meat-reducers" — a consumer group who is primarily motivated by health consciousness and weight management. Consumers who identify as vegan, vegetarian or pescetarian are more likely to endorse concerns regarding animal welfare and/or environmentalism as primary motivators. Meat substitution has a long history. Tofu, a popular meat analogue made from soybeans, was known in China during the period of the Western Han dynasty (206 BCE – 9 CE). A document written by Tao Gu (903–970) describes how tofu was called "small mutton" and valued as an imitation meat. Meat analogues such as tofu and wheat gluten are associated with Buddhist cuisine in China and other parts of East Asia. In Medieval Europe, meat analogues were popular during the Christian observance of Lent, when the consumption of meat from warm-blooded animals is forbidden. In the 2010s, owing to concern over global warming, demand for meat from a growing middle class, and major investments by companies such as Beyond Meat and Impossible Foods, there was an increase in awareness and the market size for meat analogues in Western and Westernized markets.
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  • 24 Oct 2022
Topic Review
Osmium-183
Osmium (76Os) has seven naturally occurring isotopes, five of which are stable: 187Os, 188Os, 189Os, 190Os, and (most abundant) 192Os. The other natural isotopes, 184Os, and 186Os, have extremely long half-life (1.12×1013 years and 2×1015 years, respectively) and for practical purposes can be considered to be stable as well. 187Os is the daughter of 187Re (half-life 4.56×1010 years) and is most often measured in an 187Os/188Os ratio. This ratio, as well as the 187Re/188Os ratio, have been used extensively in dating terrestrial as well as meteoric rocks. It has also been used to measure the intensity of continental weathering over geologic time and to fix minimum ages for stabilization of the mantle roots of continental cratons. However, the most notable application of Os in dating has been in conjunction with iridium, to analyze the layer of shocked quartz along the Cretaceous–Paleogene boundary that marks the extinction of the dinosaurs 66 million years ago. There are also 30 artificial radioisotopes, the longest-lived of which is 194Os with a half-life of six years; all others have half-lives under 94 days. There are also nine known nuclear isomers, the longest-lived of which is 191mOs with a half-life of 13.10 hours. All isotopes and nuclear isomers of osmium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.
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Topic Review
Mercedes-Benz OM138 Engine
The Mercedes-Benz OM 138 is a diesel engine manufactured by Daimler-Benz: 5,719 were produced between 1935 and 1940[A 1] It was the first diesel engine especially developed and made for a passenger car. The first vehicle powered by the OM 138 was the Mercedes-Benz W 138. The light Mercedes-Benz trucks L 1100 and L 1500 as well as the bus O 1500[A 2] were also offered with the OM 138 as an alternative to an otto engine.
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  • 24 Oct 2022
Topic Review
USS John Hancock (1850)
USS John Hancock was an armed steam tug in the United States Navy during the 1850s. She and her crew saw action against rioters in Massachusetts , filbusters in Cuba, rebels in China , and Native Americans in the Washington Territory. She took part in a hydrographic surveying expedition to East Asia and the Pacific Ocean. After her U.S. Navy service ended, John Hancock operated under the United States Department of State, served as floating powder magazine, and entered commercial service as a cod-fishing schooner before she was wrecked in 1893.
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Topic Review
Herfindahl–Hirschman Index
The Herfindahl index (also known as Herfindahl–Hirschman Index, HHI, or sometimes HHI-score) is a measure of the size of firms in relation to the industry they are in and an indicator of the amount of competition among them. Named after economists Orris C. Herfindahl and Albert O. Hirschman, it is an economic concept widely applied in competition law, antitrust and also technology management. HHI is calculated by squaring the market share of each competing firm in the industry and then summing the resulting numbers,(sometimes limited to the 50 largest firms), where the market shares are expressed as fractions or points. The result is proportional to the average market share, weighted by market share. As such, it can range from 0 to 1.0, moving from a huge number of very small firms to a single monopolistic producer. Increases in the Herfindahl index generally indicate a decrease in competition and an increase of market power, whereas decreases indicate the opposite. Alternatively, if whole percentages are used, the index ranges from 0 to 10,000 "points". For example, an index of .25 is the same as 2,500 points. The major benefit of the Herfindahl index in relationship to such measures as the concentration ratio is that it gives more weight to larger firms. Other benefits of the Herfindahl index includes its simple calculation method and the small amount of easily obtainable data required for the calculation. The measure is essentially equivalent to the Simpson diversity index, which is a diversity index used in ecology; the inverse participation ratio (IPR) in physics; and the effective number of parties index in politics.
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  • 24 Oct 2022
Topic Review
Locative Media
Locative media or location-based media (LBM) are media of communication functionally bound to a location. The physical implementation of locative media, however, is not bound to the same location to which the content refers. Location-based media delivers multimedia and other content directly to the user of a mobile device dependent upon their location. Location information determined by means such as mobile phone tracking and other emerging real-time locating system technologies like Wi-Fi or RFID can be used to customize media content presented on the device. Locative media are digital media applied to real places and thus triggering real social interactions. While mobile technologies such as the Global Positioning System (GPS), laptop computers and mobile phones enable locative media, they are not the goal for the development of projects in this field.
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  • 24 Oct 2022
Topic Review
Toons Mag
Toons Mag is a cartoon magazine that offers a global online platform for publishing editorial cartoons, comics, caricatures, illustrations, and related news. It is a multilingual publication and organizer of an international cartoon contest and exhibitions. It was founded in 2009 by cartoonist Arifur Rahman, based in Drøbak, Norway.
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  • 24 Oct 2022
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