concentration

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concentration

 [kon″sen-tra´shun]
1. increase in strength by evaporation.
2. the ratio of the mass or volume of a solute to the mass or volume of the solution or solvent.
3. intense mental focus.
hydrogen ion concentration see hydrogen ion concentration.
mass concentration the mass of a constituent substance divided by the volume of the mixture, as milligrams per liter (mg/l).
mean corpuscular hemoglobin concentration (MCHC) the average hemoglobin concentration in erythrocytes, conventionally expressed in “per cent,” meaning grams per deciliter of red blood cells, obtained by dividing the blood hemoglobin concentration (in g/dl) by the hematocrit (in l/l): MCHC = Hb/Hct.
minimal alveolar concentration (MAC) the concentration of anesthetic that at a pressure of 1 atmosphere produces immobility in 50 per cent of subjects exposed to a noxious stimulus.
minimal bactericidal concentration (MBC) the lowest concentration of a given antibiotic required to kill a specific organism.
minimal inhibitory concentration (MIC) the lowest concentration of a given antibiotic that inhibits the growth of a specific organism.
molar concentration the concentration of a substance expressed in terms of molarity.
concentration test a test of renal function based on the patient's ability to concentrate urine; see also fishberg concentration test.

con·cen·tra·tion (c),

(kon'sen-trā'shŭn),
1. A preparation made by extracting a crude drug, precipitating it from the solution, and drying.
2. Increasing the amount of solute in a given volume of solution by evaporation of the solvent.
3. The quantity of a substance per unit volume or weight. In renal physiology, symbol U for urinary concentration, P for plasma concentration; in respiratory physiology, symbol C for amount per unit volume in blood, F for fractional concentration (mole fraction or volume per volume) in dried gas; subscripts indicate location and chemical species.
[L. con-, together, + centrum, center]

concentration

/con·cen·tra·tion/ (kon″sen-tra´shun)
1. increase in strength by evaporation.
2. the ratio of the mass or volume of a solute to the mass or volume of the solution or solvent.

hydrogen ion concentration  the degree of concentration of hydrogen ions in a solution; related inversely to the pH of the solution by the equation [H+]= 10−pH.
mass concentration  the mass of a constituent substance divided by the volume of the mixture, as milligrams per liter (mg/L), etc.
mean corpuscular hemoglobin concentration  (MCHC) the average hemoglobin concentration in erythrocytes.
molar concentration  the concentration of a substance expressed in terms of molarity; symbol c.

concentration1

[kon′səntrā′shən]
Etymology: L, concentratio
1 increase in strength by evaporation.
2 the ratio of the mass or volume of a solute to the mass or volume of the solution or solvent. See also molality, molarity.
3 to focus or direct one's thoughts or attention.
4 a means of expressing the amount of herb and solvent used in formulating an herbal preparation. For example, a tincture with a 1:5 concentration contains 1 part of the herb in grams to 5 parts of the solvent in milliliters. Concentration is not the same thing as potency.

concentration2

a nursing outcome from the Nursing Outcomes Classification (NOC) defined as ability to focus on a specific stimulus. See also Nursing Outcomes Classification.
Chemistry The ratio of a mass or volume of a solute to the mass or volume of a solvent
Epidemiology The density of a population in a particular demographic region
Lab medicine The proportion of one molecule or substance to its diluent
Neurology The degree of mental focus required to carry out a task
Respiratory medicine The amount of a particular gas—CO2, O2—in a sampling of air from a patient

concentration

Epidemiology The density of a population in a particular demographic region Lab medicine The proportion of one molecule or substance to its diluent. See Blood alcohol concentration, Critical concentration, Critical dissolved oxygen concentration, Derived air concentration, Minimum bactericidal concentration, Minimum effective concentration, Minimum inhibitory concentration, Passive concentration, Peak serum concentration, Potentially toxic concentration, Serum concentration, Steady-state serum concentration, Total drug concentration, Trough serum concentration Neurology A general term for the degree of mental focus required to carry out a task Toxicology The ratio of a mass or volume of a solute to the mass or volume of a solvent. See Lethal concentration, Median lethal concentration, Minimum detectable concentration.

con·cen·tra·tion

(c) (kon'sĕn-trā'shŭn)
1. A preparation made by extracting a crude drug, precipitating from the solution, and drying.
2. Increasing the amount of solute in a given volume of solution by evaporation of the solvent.
3. The quantity of a substance per unit volume or weight.
4. physiology Symbol U for urinary concentration, P for plasma concentration.
5. respiratory physiology Symbol C for amount per unit volume in blood, F for fractional concentration (mole fraction or volume per volume) in dried gas.
[L. con-, together, + centrum, center]

Concentration

Refers to the amount of solute present in a solution, compared to the total amount of solvent.
Mentioned in: Diabetes Insipidus

concentration,

n the amount of a solute (substance) dissolved in a specific amount of solvent. This number may be represented as a percentage (%), grams per liter, or as a mole fraction.

con·cen·tra·tion

(kon'sĕn-trā'shŭn)
A preparation made by extracting a crude drug, precipitating it from the solution, and drying it.
[L. con-, together, + centrum, center]

concentration

1. increase in strength by evaporation.
2. the ratio of the mass or volume of a solute to the mass or volume of the solution or solvent.

hydrogen ion concentration
an expression of the degree of acidity or alkalinity (pH) of a solution. See also acid-base balance.
mass concentration
the mass of a constituent substance divided by the volume of the mixture, as milligrams per liter (mg/l).
minimum effective concentration
the threshold level of a drug in plasma below which the efficiency of the drug as a treatment drops off sharply.
molar concentration
the amount of a constituent in moles (millimoles or micromoles) divided by the volume of the mixture, as millimoles per liter (mmol/l).
concentration test
a test of renal function based on the patient's ability to concentrate urine. See water deprivation test.

Patient discussion about concentration

Q. Where to concentrate on while losing weight and how? a strongest muscle and largest muscle reduction will help me in losing weight. Where to concentrate on while losing weight and how?

A. why not do a sport that activates more muscles then just one..? running or swimming? those actions work on groups of big muscles and on your heart and lungs system that is very important in order to get in shape.

Q. Does anyone have ideas for ways to overcome concentration problems without depending on medications? I'm reallllllly trying hard to study for my final exams and my ADD seems to bother me every time I touch the desk. Sometimes my thoughts fly out when I only think of how much I still have to study today!!! please- help if you can... I really don't want to start with meds...

A. Omega-3 fatty acids, phosphatidylserine, zinc and magnesium may have benefits with regard to ADD symptoms. i take omega-3 fatty acids every day for the past year and it helped me go threw a ruff year of studying.

More discussions about concentration
References in periodicals archive ?
The serum concentrations of S100B and P53 were measured using chemiluminescence- immunometric assay (CIA) and enzyme-linked immunosorbent assay (ELISA), respectively.
The nitrogen (ppm) that precipitates as aluminum nitride is given by the difference between the concentrations of nitrogen at 2,100F and 2,552F for any given level of aluminum.
We have graphed model results for a case with 50 mg/L oxalate concentration and calcium concentrations varying from 50 to 150 mg/L.
2 of the online mathematical model), which is considerably higher than the concentrations in Figure 3.
Acquisitions of multiline targets may provide unrecognized value creation potential due to the possibility of subsequently divesting certain of the acquiree's business lines in order to increase the overall concentration level of the acquirer.
4 points as lifetime average blood lead concentrations increased from 1-10 [micro]g per deciliter.
The researchers state that increasing dietary protein intake from 12% to 220/o of total energy, with a corresponding increase in methionine intake, does not increase plasma homocysteine concentrations.
Although this study was conducted with the assistance of only one subject, we tested our system with both low and high concentrations of nasal NO, and in every situation, the off-line measurement proved to be reliable.
Although there are many other important factors to be considered in obtaining good adhesion that are beyond the scope of this article, it is reasonable to believe that these other factors all help maintain the proper concentrations of moisture, sulfur and copper at the rubber brass interface.
The measured fluorescence intensities corresponding to the various standard solutions and the corresponding fluorophore concentrations can be displayed on a graph with the fluorescence intensity signal measured by the user along the vertical axis and the fluorophore concentrations of the standards along the horizontal axis [16].
When the concentrations are uneven, water flows through the membrane to balance things out.