Phase Angle, Frailty and Mortality in Older Adults. BACKGROUNDFrailty is a multidimensional phenotype that describes declining physical function and a vulnerability to adverse outcomes in the setting of physical stress such as illness or hospitalization. Phase angle is a composite measure of tissue resistance and reactance measured via bioelectrical impedance analysis (BIA). Whether phase angle is associated with frailty and mortality in the general population is unknown. Since introduction of the pedicle screw-rod system, short-segment pedicle screw fixation has been widely adopted for thoracolumbar burst fractures (TLBF). Welcome to the EPSG Geodetic Parameter Dataset; The EPSG Geodetic Parameter Dataset is a structured dataset of Coordinate Reference Systems and Coordinate. 5 Monitoring of patients with ocular hypertension, chronic open angle glaucoma and suspected chronic open angle glaucoma. See full prescribing. Magnetic Resonance Angiography (MRA) Magnetic Resonance Angiography involves the use of magnetic resonance imaging to examine blood vessels in key areas of the body. Geometry is all about shapes and their properties. If you like playing with objects, or like drawing, then geometry is for you! Geometry can be divided into. OBJECTIVETo evaluate associations among phase angle, frailty and mortality. DESIGNPopulation- based survey. ![]() SETTINGThird National Health and Nutritional Examination Survey (1. PARTICIPANTSIn all, 4,6. MEASUREMENTSFrailty was defined according to a set of criteria derived from a definition previously described and validated. RESULTSNarrow phase angle (the lowest quintile) was associated with a four- fold higher odds of frailty among women and a three- fold higher odds of frailty among men, adjusted for age, sex, race- ethnicity and comorbidity. Over a 1. 2- year follow- up period, the adjusted relative hazard for mortality associated with narrow phase angle was 2. Accelerometers have been widely.Narrow phase angle was significantly associated with mortality even among participants with little or no comorbidity. LIMITATIONSAnalyses of BIA and frailty were cross- sectional; BIA was not measured serially and incident frailty during follow- up was not assessed. Participants examined at home were excluded from analysis because they did not undergo BIA. CONCLUSIONSNarrow phase angle is associated with frailty and mortality independent of age and comorbidity. Physical measurement . Time, distance, mass, temperature, force, power, and all other physical quantities (or parameters or variables), as well as the properties of matter, materials, and devices, must be described and measured in terms which have the same meaning for everyone. The measuring device or instrument is calibrated (that is, the functional relationship between its indication and the magnitude of the measured quantity is determined) by direct or indirect comparison with a standard which embodies, possesses, or generates a fixed or reproducible magnitude of the physical quantity which is taken as the unit or some multiple or fraction of the unit. Any measured quantity may thus be expressed by a number (the magnitude ratio) and the name of the unit, for example, a length of 1. The general area of scientific activity relating to standards and units and the accuracy of measurement is called metrology. See. Units of measurement. Metric system. The basic unit of length in the decimal metric system was defined as one ten- millionth of the Earth's polar quadrant (as determined from latitude surveys), and is termed the meter. The basic unit for mass was defined as the mass of a cubic decimeter of water, to be called the kilogram. The United States has adopted the Metric Conversion Act, declaring that “the policy of the U. S. Metric Board “to coordinate the voluntary conversion to the metric system.” However, English units have become almost universal in some worldwide industries—for example, dimensions of oil- drilling equipment, or altitude measurement in aviation. Thus it is likely that there will always be exceptions to uniformity, requiring special knowledge of special units for at least some people even as the whole world “goes metric” in principle. International System of Units (SI)At present the International System of Units (abbreviated SI, from the French Syst. Units for all other quantities are derived from these seven units. In Table 2 are listed 2. SI derived units with special names. These units are derived from the base units in a coherent manner, which means they are expressed as products and quotients of the seven base units without numerical factors. All other SI derived units are similarly derived in a coherent manner from the 2. SI units. For use with the SI units, there is a set of 2. Table 3) to form multiples and submultiples of these units. For mass, the prefixes are to be applied to the gram instead of to the SI unit, the kilogram. See. Dimensional analysis. SI base units. Quantity*Unit name. Symbol. Lengthmeter m. Masskilogram kg. Timesecond s. Electric currentampere AThermodynamic temperaturekelvin KAmount of substancemole mol. Luminous intensitycandela cd *Quantity here and in Table 2 means a measurable attribute. The SI units together with the SI prefixes provide a logical and interconnected framework for measurements in science, industry, and commerce. In some cases, quantities are commonly expressed in terms of fundamental constants of nature, and use of these constants or “natural units” is acceptable. See. Fundamental constants. SI derived units with special names. Expressionin terms of. Expression in terms of. Quantity. Unit name. Symbolother units. SI base units. Plane angleradian radm . The units that are accepted for continued use with the International System are listed in Table 4. It is likewise necessary to recognize, outside the International System, the following units which are used in specialized fields: Logarithmic measures such as p. H, d. B (decibel), and Np (neper) are acceptable. See. Atomic mass unit, Decibel, Electronvolt. Units in use with the International System. Name. Symbol. Value in SI unit. Minute min. 1 min = 6. Hour h. 1 h = 6. 0 min = 3. Day d. 1 d = 2. 4 h = 8. Degree . Natural logarithms are used to obtain the numerical values of quantities expressed in nepers. The neper is coherent with the SI, but is not yet adopted as an SI unit. Logarithms to base ten are used to obtain the numerical values of quantities expressed in bels. The internationally accepted definitions for the seven base units follow: Mass. The kilogram (kg) is equal to the mass of the International Prototype Kilogram. The International Prototype is a platinum- iridium cylinder preserved at the International Bureau of Weights and Measures at S. No basic property of matter involving mass can be measured with more precision than is possible in comparing kilogram masses by weighing, about 1 part in 1. See. Mass. Length. The meter is defined in terms of time and the speed of light: “The meter is the length of the path traveled by light in a vacuum during a time interval of 1/2. This definition defines the speed of light to be exactly 2. See. Light. The most accurate method of realizing the meter is by means of an interferometrically measured distance by fringe counting in which each vacuum fringe is a half wavelength from the next one. This wavelength, . To this end, major standards laboratories have measured the frequencies of several lasers stabilized to narrow molecular absorptions in the visible and near- infrared spectral regions. These stabilized lasers now serve as standards of length. See. Interferometry, Wavelength standards. Time interval. The second (s) is the duration of 9 1. In the best equipments the stability and accuracy of the cesium frequency generator correspond to an uncertainty of a few parts in 1. The second was long defined, for physical measurements as well as for civil affairs, as 1/8. Earth on its axis with respect to the Sun. Because of the slight slowing of the Earth's rotation rate, now averaging about 1 second per year (that is, 3 parts in 1. A time scale called Coordinated Universal Time (UTC) recommended by the General Conference of Weights and Measures (CGPM) in 1. TAI) by an exact whole number of seconds. This difference is adjusted occasionally by the use of a positive or negative leap second at the end of certain months to keep UTC in agreement with the time defined by the rotation of the Earth with an approximation better than 9/1. See. Atomic clock, Frequency measurement, Time. Temperature. The kelvin (K), the unit of thermodynamic temperature, is the fraction 1/2. The unit kelvin and its symbol K should also be used to express an interval or differences of temp- erature. To provide convenient and adequately accurate means for practical realization and measurement of temperature, the International Temperature Scale is used, based on the assigned values of the temperatures of a number of reproducible equilibrium states (defining fixed points), on standard instruments calibrated at those temperatures, and on vapor- pressure temperature relationships. Interpolation between the fixed- point temperatures is provided by formulas used to establish the relation between indications of the standard instruments and values of International Temperature. An extensive revision, which came into effect in 1. ITS- 9. 0. See. Temperature, Temperature measurement. Electric current. The ampere (A) is that constant current which, if maintained in two straight parallel conductors of infinite length and of negligible circular sections, and placed 1 meter apart in a vacuum, would produce between these conductors a force equal to 2 . See. Electrical units and standards. Luminous intensity. The CGPM, in 1. 97. SI unit candela as the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 5. See. Light, Luminous efficacy, Luminous efficiency, Luminous intensity, Photometry, Radiometry. Amount of substance. The mole is the amount of substance of a system which contains as many elementary entities as there are atoms in 0. When the mole is used, the elementary entities must be specified, and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.
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