| D012044 |
Regression Analysis |
Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable. |
Regression Diagnostics,Statistical Regression,Analysis, Regression,Analyses, Regression,Diagnostics, Regression,Regression Analyses,Regression, Statistical,Regressions, Statistical,Statistical Regressions |
|
| D002118 |
Calcium |
A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. |
Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation |
|
| D004784 |
Environmental Monitoring |
The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment. |
Monitoring, Environmental,Environmental Surveillance,Surveillance, Environmental |
|
| D005290 |
Ferric Compounds |
Inorganic or organic compounds containing trivalent iron. |
Compounds, Ferric |
|
| D005618 |
Fresh Water |
Water containing no significant amounts of salts, such as water from RIVERS and LAKES. |
Freshwater,Fresh Waters,Freshwaters,Water, Fresh,Waters, Fresh |
|
| D000644 |
Quaternary Ammonium Compounds |
Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN |
Quaternary Ammonium Compound,Ammonium Compound, Quaternary,Ammonium Compounds, Quaternary,Compound, Quaternary Ammonium |
|
| D001151 |
Arsenic |
A shiny gray element with atomic symbol As, atomic number 33, and atomic weight 75. It occurs throughout the universe, mostly in the form of metallic arsenides. Most forms are toxic. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), arsenic and certain arsenic compounds have been listed as known carcinogens. (From Merck Index, 11th ed) |
Arsenic-75,Arsenic 75 |
|
| D001464 |
Barium |
An element of the alkaline earth group of metals. It has an atomic symbol Ba, atomic number 56, and atomic weight 138. All of its acid-soluble salts are poisonous. |
|
|
| D014874 |
Water Pollutants, Chemical |
Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water. |
Chemical Water Pollutants,Landfill Leachate,Leachate, Landfill,Pollutants, Chemical Water |
|
| D019015 |
Geologic Sediments |
A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689) |
Marine Oil Snow,Sediments, Geologic,Sediments, Marine,Geologic Sediment,Marine Snow,Sediment, Geologic,Marine Oil Snows,Marine Sediment,Marine Sediments,Oil Snow, Marine,Sediment, Marine,Snow, Marine Oil |
|