919 resultados para Gradient terms
Resumo:
The National Health Planning and Resources Development Act of 1974 (Public Law 93-641) requires that health systems agencies (HSAs) plan for their health service areas by the use of existing data to the maximum extent practicable. Health planning is based on the identificaton of health needs; however, HSAs are, at present, identifying health needs in their service areas in some approximate terms. This lack of specificity has greatly reduced the effectiveness of health planning. The intent of this study is, therefore, to explore the feasibility of predicting community levels of hospitalized morbidity by diagnosis by the use of existing data so as to allow health planners to plan for the services associated with specific diagnoses.^ The specific objectives of this study are (a) to obtain by means of multiple regression analysis a prediction equation for hospital admission by diagnosis, i.e., select the variables that are related to demand for hospital admissions; (b) to examine how pertinent the variables selected are; and (c) to see if each equation obtained predicts well for health service areas.^ The existing data on hospital admissions by diagnosis are those collected from the National Hospital Discharge Surveys, and are available in a form aggregated to the nine census divisions. When the equations established with such data are applied to local health service areas for prediction, the application is subject to the criticism of the theory of ecological fallacy. Since HSAs have to rely on the availability of existing data, it is imperative to examine whether or not the theory of ecological fallacy holds true in this case.^ The results of the study show that the equations established are highly significant and the independent variables in the equations explain the variation in the demand for hospital admission well. The predictability of these equations is good when they are applied to areas at the same ecological level but become poor, predominantly due to ecological fallacy, when they are applied to health service areas.^ It is concluded that HSAs can not predict hospital admissions by diagnosis without primary data collection as discouraged by Public Law 93-641. ^
Resumo:
Composition and distribution of megabenthic communities around Svalbard were investigated in June/July 1991 with 20 Agassiz trawl and 5 bottom trawl hauls in depths between 100 and 2100 m. About 370 species, ranging from sponges to fish, were identified in the catches. Species numbers per station ranged from 21 to 86. Brittle stars, such as Ophiacantha bidentata, Ophiura sarsi and Ophiocten sericeum, were most important in terms of constancy and relative abundance in the catches. Other prominent faunal elements were eunephthyid alcyonarians, bivalves, shrimps, sea stars and fish (Gadidae, Zoarcidae, Cottidae). Multivariate analyses of the species and environmental data sets showed that the spatial distribution of the megabenthos was characterized by a pronounced depth zonation: abyssal, bathyal, off-shore shelf and fjordic communities were discriminated. However, a gradient in sediment properties, especially the organic carbon content, seemed to superimpose on the bathymetric pattern. Both main factors are interpreted as proxies of the average food availability, which is, hence, suggested to have the strongest influence in structuring megabenthic communities off Svalbard.
Resumo:
A portable Fourier transform spectrometer (FTS), model EM27/SUN, was deployed onboard the research vessel Polarstern to measure the column-average dry air mole fractions of carbon dioxide (XCO2) and methane (XCH4) by means of direct sunlight absorption spectrometry. We report on technical developments as well as data calibration and reduction measures required to achieve the targeted accuracy of fractions of a percent in retrieved XCO2 and XCH4 while operating the instrument under field conditions onboard the moving platform during a 6-week cruise on the Atlantic from Cape Town (South Africa, 34° S, 18° E; 5 March 2014) to Bremerhaven (Germany, 54° N, 19° E; 14 April 2014). We demonstrate that our solar tracker typically achieved a tracking precision of better than 0.05° toward the center of the sun throughout the ship cruise which facilitates accurate XCO2 and XCH4 retrievals even under harsh ambient wind conditions. We define several quality filters that screen spectra, e.g., when the field of view was partially obstructed by ship structures or when the lines-of-sight crossed the ship exhaust plume. The measurements in clean oceanic air, can be used to characterize a spurious air-mass dependency. After the campaign, deployment of the spectrometer alongside the TCCON (Total Carbon Column Observing Network) instrument at Karlsruhe, Germany, allowed for determining a calibration factor that makes the entire campaign record traceable to World Meteorological Organization (WMO) standards. Comparisons to observations of the GOSAT satellite and concentration fields modeled by the European Centre for Medium-Range Weather Forecasts (ECMWF) Copernicus Atmosphere Monitoring Service (CAMS) demonstrate that the observational setup is well suited to provide validation opportunities above the ocean and along interhemispheric transects.
Resumo:
A quantitative study of late Cenozoic silicoflagellates from the northwestern Pacific sites of Deep Sea Drilling Project Leg 86 shows a relative paleotemperature (Ts) gradient with lowest values (Ts = 30) in the north. Some new ecostratigraphic relations for the region are indicated, such as the last common occurrence of Dictyocha brevispina at 2.6 - 3.0 m.y. ago during a cool interval. Elements of North Pacific and low-latitude biostratigraphic zonations can be identified, but the mixing of cool- and warm-indicator taxa prompted the definition of the new Miocene Mesocena hexalitha Subzone and Pliocene Distephanus jimlingii Subzone. Scanning-electron microscope study of Leg 86 silicoflagellates was done to determine whether various types of skeletal surface texture are temperature dependent. To conduct the study we organized a new surface-texture descriptive code, which characterizes the apical structure/basal ring/spine sequence using new definitions of the terms crenulate (C), linear (L), nodular (N), reticulate (R), and smooth (S). One new silicoflagellate genus, Caryocha Bukry et Monechi, n. gen., is described and several new combinations are made.