Circulatory systemThe blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek kardia meaning heart, and from Latin vascula meaning vessels). The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit.
Law of demandIn microeconomics, the law of demand is a fundamental principle which states that there is an inverse relationship between price and quantity demanded. In other words, "conditional on all else being equal, as the price of a good increases (↑), quantity demanded will decrease (↓); conversely, as the price of a good decreases (↓), quantity demanded will increase (↑)". Alfred Marshall worded this as: "When we say that a person's demand for anything increases, we mean that he will buy more of it than he would before at the same price, and that he will buy as much of it as before at a higher price".
Beta-glucanBeta-glucans, β-glucans comprise a group of β-D-glucose polysaccharides (glucans) naturally occurring in the cell walls of cereals, bacteria, and fungi, with significantly differing physicochemical properties dependent on source. Typically, β-glucans form a linear backbone with 1–3 β-glycosidic bonds but vary with respect to molecular mass, solubility, viscosity, branching structure, and gelation properties, causing diverse physiological effects in animals.
Enigma machineThe Enigma machine is a cipher device developed and used in the early- to mid-20th century to protect commercial, diplomatic, and military communication. It was employed extensively by Nazi Germany during World War II, in all branches of the German military. The Enigma machine was considered so secure that it was used to encipher the most top-secret messages. The Enigma has an electromechanical rotor mechanism that scrambles the 26 letters of the alphabet.
AnomerIn carbohydrate chemistry, a pair of anomers () is a pair of near-identical stereoisomers or diastereomers that differ at only the anomeric carbon, the carbon that bears the aldehyde or ketone functional group in the sugar's open-chain form. However, in order for anomers to exist, the sugar must be in its cyclic form, since in open-chain form, the anomeric carbon is planar and thus achiral. More formally stated, then, an anomer is an epimer at the hemiacetal/hemiketal carbon in a cyclic saccharide.
Hebern rotor machineThe Hebern Rotor Machine was an electro-mechanical encryption machine built by combining the mechanical parts of a standard typewriter with the electrical parts of an electric typewriter, connecting the two through a scrambler. It is the first example (though just barely) of a class of machines known as rotor machines that would become the primary form of encryption during World War II and for some time after, and which included such famous examples as the German Enigma.
HypovolemiaHypovolemia, also known as volume depletion or volume contraction, is a state of abnormally low extracellular fluid in the body. This may be due to either a loss of both salt and water or a decrease in blood volume. Hypovolemia refers to the loss of extracellular fluid and should not be confused with dehydration. Hypovolemia is caused by a variety of events, but these can be simplified into two categories: those that are associated with kidney function and those that are not.
HoneyHoney is a sweet and viscous substance made by several bees, the best-known of which are honey bees. Honey is made and stored to nourish bee colonies. Bees produce honey by gathering and then refining the sugary secretions of plants (primarily floral nectar) or the secretions of other insects, like the honeydew of aphids. This refinement takes place both within individual bees, through regurgitation and enzymatic activity, and during storage in the hive, through water evaporation that concentrates the honey's sugars until it is thick and viscous.
ImmunosuppressionImmunosuppression is a reduction of the activation or efficacy of the immune system. Some portions of the immune system itself have immunosuppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reaction to treatment of other conditions. In general, deliberately induced immunosuppression is performed to prevent the body from rejecting an organ transplant.
FastingFasting is the abstention from eating and sometimes drinking. From a purely physiological context, "fasting" may refer to the metabolic status of a person who has not eaten overnight (see "Breakfast"), or to the metabolic state achieved after complete digestion and absorption of a meal. Metabolic changes in the fasting state begin after absorption of a meal (typically 3–5 hours after eating). A diagnostic fast refers to prolonged fasting from 1 to 100 hours (depending on age) conducted under observation to facilitate the investigation of a health complication, usually hypoglycemia.