16,646 research outputs found
Land use Effects on Ground Water Quality in Carbonate Rock Terrain
A control site with a natural setting and an experimental site with significant agriculture land use were studied in the Ozark Region of Arkansas in order to determine the effect of land use on water quality in a carbonate rock terrain. The vast majority of the two sites have the Boone Limestone exposed which combined with the underlying St. Joe is the major aquifer for drinking water in the area. The sites also are similar in terms of lineament patterns (number, length and orientation), soil, slope and vegetation. Ground water samples were collected primarily from springs during three seasons (late summer-early fall, winter and spring). All three seasonal collections exhibited statistically higher NO3 (2.31 versus 0.81 mg/L) and Cl (9.9 versus 2.7 mg/L) concentrations in the experimental site. During the winter and spring collections, the experimental site also exhibited statistically higher concentrations (0.5 to 3x) of PO4, SO4, Na, K and Ca. Heavy metals were analyzed in the winter samples; however, the differences between the two sites were small because the absolute values for the two sites were low. For example, the largest difference for a heavy metal was 19 μg/L for Mn (12 versus 31 μg/L). Bacteria determined from the spring season samples showed that the experimental site had significantly higher counts of fecal coliform (86 versus 0.4 col - onies/100 mL) and fecal Streptococcus (39 versus 3 colonies/100 mL) types than the control site. Three springs were also sampled periodically following a rain event of 10 cm. Whereas, levels of specific conductance, NO3, Ca and Na decreased in all three springs, PO4, K, SO4 and fecal coliform increased significantly, primarily in the two experimental springs. The increase of these parameters indicates that they are more available in the experimental area. Based on these results and elemental correlations, it appears that cattle manure, the spreading of chicken manure and commercial fertilizers, and septic tank effluent, individually or in combination, are affecting the water quality of the experimental site. However, most of the ground water samples meet EPA drinking water standards with the possible exception of bacteria
Gamma Ray Bursts in the Era of Rapid Followup
We present a status report on the study of gamma-ray bursts (GRB) in the era
of rapid follow-up using the world's largest robotic optical telescopes - the
2-m Liverpool and Faulkes telescopes. Within the context of key unsolved issues
in GRB physics, we describe (1) our innovative software that allows real-time
automatic analysis and interpretation of GRB light curves, (2) the novel
instrumentation that allows unique types of observations (in particular, early
time polarisation measurements) and (3) the key science questions and
discoveries to which robotic observations are ideally suited, concluding with a
summary of current understanding of GRB physics provided by combining rapid
optical observations with simultaneous observations at other wavelengths.Comment: 20 pages, 12 figures; Review article accepted for publication in
Advances in Astronomy, special issue 'Robotic Astronomy (Hindawi Publishing
Corporation)
Addendum no. 1 to final development report
Pseudo-linearity concept impact on linear filters designed to ease pulse crowding effects at high bit densitie
Use of programme budgeting and marginal analysis to set priorities for local NHS dental services: learning from the north east of England
Background - Priority setting is necessary where competing demands exceed the finite resources available. The aim of the study was to develop and test a prioritization framework based upon programme budgeting and marginal analysis (PBMA) as a tool to assist National Health Service (NHS) commissioners in their management of resources for local NHS dental services.
Methods - Twenty-seven stakeholders (5 dentists, 8 commissioners and 14 patients) participated in a case-study based in a former NHS commissioning organization in the north of England. Stakeholders modified local decision-making criteria and applied them to a number of different scenarios.
Results - The majority of financial resources for NHS dental services in the commissioning organization studied were allocated to primary care dental practitioners’ contracts in perpetuity, potentially constraining commissioners’ abilities to shift resources. Compiling the programme budget was successful, but organizational flux and difficulties engaging local NHS commissioners significantly impacted upon the marginal analysis phase.
Conclusions - NHS dental practitioners’ contracts resemble budget-silos which do not facilitate local resource reallocation. ‘Context-specific’ factors significantly challenged the successful implementation and impact of PBMA. A local PBMA champion embedded within commissioning organizations should be considered. Participants found visual depiction of the cost-value ratio helpful during their initial priority setting deliberations
Structural and lithologic study of northern California Coast Range and Sacramento Valley, California
The author has identified the following significant results. Photgeologic examination of repetitive multispectral ERTS-1 imagery of Northern California has disclosed several systems of linear features which may be important for the interpretation of the structural history of California. They are separated from an orthogonal system of linears in the Klamath Mts. by a set of discontinuous southeast-trending linear features (the Mendocino system) which is traceable from the Pacific Coast, at Cape Mendocino, into the eastern foothills of the Sierra Nevada. Within the Sierra Nevada, the Mendocino system separates the north-trending Sierran system from a set of linears characteristic of the Modoc Plateau. With minor exception, little overlap exists among the systems which suggests a decipherable chronology and evolutionary history for the region. The San Andres system of linears appears to truncate or co-exist with most of the other systems in the northern Coast Ranges. The Mendocino system truncates the Klamath, Sierran, and Modoc systems. The Sierran system may represent fundamental and long-persisting pre-late Paleozoic zones of crustal weakness which have been reactivated from time to time. The Mendocino system was possibly developed in early Mesozoic and is important to the structural framework of Northern California
A computer simulation of digital recording Final development progress report, 29 Dec. 1966 - 29 Dec. 1967
Fourier series digital computer simulation of tape recording process - signal detection in prescence of white Gaussian nois
Land use change detection with LANDSAT-2 data for monitoring and predicting regional water quality degradation
There are no author-identified significant results in this report
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