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Topic Review
WDFW Toxics in Biota Fish Monitoring
Fish are an important component of the Washington Department of Fish and Wildlife's (WDFW) Toxics in Biota Program, part of the Puget Sound Ecosystem Monitoring Program (PSEMP, recently renamed from PSAMP). Since 1989 fish indicator species have been used to monitor contamination of Puget Sound by chemicals such as poly-chlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), pesticides, and metals. English Sole, the first species studied for the Toxics in Biota Program, have been used for monitoring by WDFW since 1989. As of 2015 the program also monitors copper rockfish, quillback rockfish, brown rockfish, coho salmon, chinook salmon, Pacific herring, and Pacific staghorn sculpin. Exposure and effects of each contaminant are monitored for each species, and more in-depth studies of specific regions are performed if monitoring indicates a contamination problem. Geographical characteristics making Puget Sound especially susceptible to contaminants include funneling of fish through narrow inlets, restricted exchange of water, shallow sea floor sills, and freshwater inputs from urban sources. One of the largest sources of contaminants is stormwater runoff. During heavy rain events metals, persistent organic pollutants (POPs), and pesticides flow untreated into local waterways, streams, and lakes. Impervious surfaces such as roads provide a route for deposition of metals and POPs by cars and industrial emissions, before subsequent discharge into nearby water bodies. The highly urbanized coastline of southern Puget Sound results in stormwater runoff containing high concentrations of contaminants.
  • 183
  • 17 Oct 2022
Topic Review
Water Ionizer
A water ionizer (also known as an alkaline ionizer) is a home appliance which claims to raise the pH of drinking water by using electrolysis to separate the incoming water stream into acidic and alkaline components. The alkaline stream of the treated water is called alkaline water. Proponents claim that consumption of alkaline water results in a variety of health benefits, making it similar to the alternative health practice of alkaline diets. Such claims violate basic principles of chemistry and physiology. There is no medical evidence for any health benefits of alkaline water. Extensive scientific evidence has completely debunked these claims. The machines originally became popular in Japan and other East Asian countries before becoming available in the United States and Europe.
  • 1.1K
  • 07 Nov 2022
Topic Review
Vinyl Ether
Vinyl ether is the organic compound with the formula O(CH=CH2)2. Other names include divinyl ether, divinyl oxide, ethenoxyethene. It is a colorless, volatile liquid. Under the tradename vinethene, vinyl ether was once used as an inhalation anesthetic. The analytical techniques used to study its pharmacology laid the groundwork for the testing of new anesthetic agents. Many divinyl ether derivatives of fatty acids exist in nature.
  • 588
  • 28 Oct 2022
Topic Review
Vienna Philharmonic (Coin)
The Vienna Philharmonic (German: Wiener Philharmoniker), often shortened to Philharmonic, is a bullion coin of gold, silver, or platinum produced by the Austrian Mint (Münze Österreich). The coin is named for the Vienna Philharmonic orchestra, which inspired the design of both sides. It was introduced in 1989 as a one-troy ounce (ozt), gold coin with a face value of 2,000 Austrian schillings. It is generally one of the world's best selling bullion coins. In 2002, with the adoption of the euro currency, the nominal value of the one-ounce coin was changed to 100 euros. In 2008, the Mint introduced a one-ounce silver version of the coin with a nominal value of 1.50 euros. The silver coin is also one of the top selling bullion coins, ranked third in 2013. In 2016, the mint introduced a one ounce platinum coin with a face value of 100 euros. Like any bullion coin, the value is based primarily on the metal content and the spot price of that metal on the commodities markets. The gold Philharmonic has a fineness of 999.9 (often written 0.9999, also known as 24 carat or 99.99% pure). In most countries in Europe, the gold Philharmonic is traded VAT-free while the Silver Philharmonic is partly subject to a reduced VAT rate. The coins are minted according to demand and production varies from year to year accordingly. The design on the coin remains the same each year; only the year of issue changes. From the outset, the obverse of the coin depicts the pipe organ in the Vienna Musikverein's Golden Hall. The reverse of the coin shows instruments of the Vienna Philharmonic, including Vienna horn, bassoon, harp, and four violins centered on a cello. Both designs were produced by the chief engraver of the Austrian Mint, Thomas Pesendorfer.
  • 500
  • 01 Nov 2022
Topic Review
Valence
In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules.
  • 1.3K
  • 02 Nov 2022
Topic Review
Unsaturated Fat
An unsaturated fat is a fat or fatty acid in which there is at least one double bond within the fatty acid chain. A fatty acid chain is monounsaturated if it contains one double bond, and polyunsaturated if it contains more than one double bond. Where double bonds are formed, hydrogen atoms are subtracted from the carbon chain. Thus, a saturated fat has no double bonds, has the maximum number of hydrogens bonded to the carbons, and therefore is "saturated" with hydrogen atoms. In cellular metabolism, unsaturated fat molecules contain somewhat less energy (i.e., fewer calories) than an equivalent amount of saturated fat. The greater the degree of unsaturation in a fatty acid (i.e., the more double bonds in the fatty acid) the more vulnerable it is to lipid peroxidation (rancidity). Antioxidants can protect unsaturated fat from lipid peroxidation.
  • 1.2K
  • 28 Sep 2022
Topic Review
Uncompetitive Inhibitor
Uncompetitive inhibition, also known as anti-competitive inhibition, takes place when an enzyme inhibitor binds only to the complex formed between the enzyme and the substrate (the E-S complex). Uncompetitive inhibition typically occurs in reactions with two or more substrates or products. While uncompetitive inhibition requires that an enzyme-substrate complex must be formed, non-competitive inhibition can occur with or without the substrate present. Uncompetitive inhibition is distinguished from competitive inhibition by two observations: first uncompetitive inhibition cannot be reversed by increasing [S] and second, as shown, the Lineweaver–Burk plot yields parallel rather than intersecting lines. This behavior is found in the inhibition of acetylcholinesterase by tertiary amines (R3N). Such compounds bind to the enzyme in its various forms, but the acyl-intermediate-amine complex cannot break down into enzyme plus product.
  • 16.5K
  • 16 Nov 2022
Topic Review
Unbiunium
Check temperatures Ubu: no input for C, K, F. Check temperatures Ubu: no input for C, K, F. Unbiunium, also known as eka-actinium or simply element 121, is the hypothetical chemical element with symbol Ubu and atomic number 121. Unbiunium and Ubu are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to be the first of the superactinides, and the third element in the eighth period: analogously to lanthanum and actinium, it could be considered the fifth member of group 3 and the first member of the fifth-row transition metals. It has attracted attention because of some predictions that it may be in the island of stability, although newer calculations expect the island to actually occur at a slightly lower atomic number, closer to copernicium and flerovium. Unbiunium has not yet been synthesized. Nevertheless, because it is only three elements away from the heaviest known element, oganesson (element 118), its synthesis may come in the near future; it is expected to be one of the last few reachable elements with current technology, and the limit may be anywhere between element 120 and 124. It will also likely be far more difficult to synthesize than the elements known so far up to 118, and still more difficult than elements 119 and 120. The team at RIKEN in Japan has plans to attempt the synthesis of element 121 in the future after its attempts on elements 119 and 120. The position of unbiunium in the periodic table suggests that it would have similar properties to its lighter congeners, scandium, yttrium, lanthanum, and actinium; however, relativistic effects may cause some of its properties to differ from those expected from a straight application of periodic trends. For example, unbiunium is expected to have a s2p valence electron configuration instead of the s2d of its lighter congeners in group 3, but this is not expected to significantly affect its chemistry, which is predicted to be that of a normal group 3 element; it would on the other hand significantly lower its first ionisation energy beyond what would be expected from periodic trends.
  • 4.4K
  • 25 Oct 2022
Topic Review
Unbibium
Unbibium /uːnˈbɪbiəm/, also known as eka-thorium or simply element 122, is the currently hypothetical chemical element in the periodic table with the placeholder symbol of Ubb and atomic number 122. Unbibium and Ubb are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to follow unbiunium as the second element of the superactinides, or the g-block and the fourth element of the 8th period. It has attracted recent attention, for similarly to unbiunium, it is expected to fall within the range of the island of stability. Despite many attempts, unbibium has not yet been synthesized, and therefore no natural isotopes have been found to exist. It is currently predicted that it has a g-orbital, the second element of which to have such besides unbiunium, which also has yet to be synthesized. It will most likely require nuclear fission to be produced artificially. In 2008, it was claimed to have been discovered in natural thorium samples but that claim has now been dismissed by recent repetitions of the experiment using more accurate techniques.
  • 2.6K
  • 29 Nov 2022
Topic Review
Tyrocidine
Tyrocidine is a mixture of cyclic decapeptides produced by the bacteria Bacillus brevis found in soil. It can be composed of 4 different amino acid sequences, giving tyrocidine A–D. Tyrocidine is the major constituent of tyrothricin, which also contains gramicidin. Tyrocidine was the first commercially available antibiotic, but has been found to be toxic toward human blood and reproductive cells. The function of tyrocidine within its host B. brevis is thought to be regulation of sporulation. Tyrocidines A, B, and C are cyclic decapeptides. The biosynthesis of tyrocidine involves three enzymes. Parts of its sequence are identical to gramicidin S.
  • 510
  • 15 Nov 2022
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