10,181 research outputs found

    MEDATA - A new concept in medical records management

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    Computer program for medical records managemen

    Subsurface Flow Barriers to Reduce Nitrate Leaching

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    Groundwater is a very important natural resource which directly affects many human lives. In the United States, groundwater is the source of about 22 percent of the freshwater used. About 53 percent of the total population and 97 percent of the rural population use groundwater supplies for their drinking water (Moody, 1990). Although contamination of groundwater can occur naturally, agriculture is considered to be one of the most widespread nonprofit sources of groundwater contamination. Among agricultural chemicals, nitrogen-fertilizer has been used most extensively, especially by com producers. About one million tons of nitrogen-fertilizer are used annually in Iowa. In some studies, more than 50 percent of the applied fertilizer nitrogen is not removed by the crop or stored in the soil, and leaching as a form of nitrate is thought to be a major reason for the losses (Blackmer, 1987). Leached nitrate may enter groundwater supplies. Nitrate-nitrogen concentrations found in unsaturated soil below the rootzone of agricultural fields are in the range of 5 to 100 mg!L (Bouwer, 1990). Nitrate-nitrogen concentrations in tile drainage below row crops often exceed 10 mg/L, the U.S.A. drinking water standard (Gast et al., 1978; Baker and Johnson, 1981; Timmons and Dylla, 1981; Baker et al., 1985)

    Sensible Heat Observations Reveal Soil-Water Evaporation Dynamics

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    Soil-water evaporation is important at scales ranging from microbial ecology to large-scale climate. Yet routine measurements are unable to capture rapidly shifting near-surface soil heat and water processes involved in soil-water evaporation. The objective of this study was to determine the depth and location of the evaporation zone within soil. Three-needle heat-pulse sensors were used to monitor soil heat capacity, thermal conductivity, and temperature below a bare soil surface in central Iowa during natural wetting/drying cycles. Soil heat flux and changes in heat storage were calculated from these data to obtain a balance of sensible heat components. The residual from this balance, attributed to latent heat from water vaporization, provides an estimate of in situ soil-water evaporation. As the soil dried following rainfall, results show divergence in the soil sensible heat flux with depth. Divergence in the heat flux indicates the location of a heat sink associated with soil-water evaporation. Evaporation estimates from the sensible heat balance provide depth and time patterns consistent with observed soil-water depletion patterns. Immediately after rainfall, evaporation occurred near the soil surface. Within 6 days after rainfall, the evaporation zone proceeded \u3e 13 mm into the soil profile. Evaporation rates at the 3-mm depth reached peak values \u3e 0.25 mm h−1. Evaporation occurred simultaneously at multiple measured depth increments, but with time lag between peak evaporation rates for depths deeper below the soil surface. Implementation of finescale measurement techniques for the soil sensible heat balance provides a new opportunity to improve understanding of soil-water evaporation

    Evaluation of a new, perforated heat flux plate design

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    Accurate measurement of heat flux is essential to optimize structural and process design and to improve understanding of energy transfer in natural systems. Laboratory and field experiments evaluated the performance of a new, perforated heat flux plate designed to reduce flow distortion for environmental applications. Laboratory tests involving dry and saturated sand showed that performance of the new CAPTEC plate is comparable to a solid, standard REBS plate. Very low thermal gradients may have however led to poor performance of the CAPTEC plate in saturated sand. Water infiltration and redistribution experiments using clayey and sandy soils showed an apparent reduced disruption of liquid water and vapour in the soil surrounding the CAPTEC plate as compared to solid Hukseflux and standard REBS plates. Surface area of REBS plate, though smaller than that of CAPTEC, did not lead to any significantly improved evaporation, due to perforations on CAPTEC plate. Field tests in a loam soil indicated that the CAPTEC plates were durable and produced daily total flux values within ~ 0.15 MJ m− 2 of independent estimates

    A Near-Deterministic Mutational Hotspot in Pseudomonas fluorescens Is Constructed by Multiple Interacting Genomic Features

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    Mutation—whilst stochastic—is frequently biased toward certain loci. When combined with selection, this results in highly repeatable and predictable evolutionary outcomes. Immotile variants of the bacterium Pseudomonas fluorescens (SBW25) possess a “mutational hotspot” that facilitates repeated occurrences of an identical de novo single nucleotide polymorphism when re-evolving motility, where ≥95% independent lines fix the mutation ntrB A289C. Identifying hotspots of similar potency in other genes and genomic backgrounds would prove valuable for predictive evolutionary models but to do so we must understand the genomic features that enable such a hotspot to form. Here, we reveal that genomic location, local nucleotide sequence, gene strandedness, and presence of mismatch repair proteins operate in combination to facilitate the formation of this mutational hotspot. Our study therefore provides a framework for utilizing genomic features to predict and identify hotspot positions capable of enforcing near-deterministic evolution

    Avaliação de ganho de peso e peso a desmama em bezerros pantaneiros e pantaneiro X nelore, criados a pasto.

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    O bovino Pantaneiro é uma raça local brasileira que possui entre outras características, grande adaptabilidade às condições ambientais extremas aos quais são submetidos esses animais, no seu habitat natural, o Pantanal. Devido ao sério risco de extinção, a Embrapa Pantanal e parceiros têm dedicado suas pesquisas a conservação e uso desse patrimônio genético, divulgando suas potencialidades como forma de estimular a criação dessa raça em diferentes sistemas produtivos. Com o objetivo de avaliar o ganho de peso diário (GPD) e peso a desmama (PD) de animais da raça Pantaneiro e mestiços Pantaneiro X Nelore, foram coletados pesos de machos e fêmeas ao nascimento e próximo a idade de desmama. Não houve diferença de GPD entre os grupamentos raciais para ambos os sexos. A média de GPD de bezerras Pantaneiras e mestiças foi 0,575 kg/dia e 0,654 kg/dia, respectivamente. Para bezerros Pantaneiros e mestiços, os valores encontrados foram 0,643 kg/dia e 0,692 kg/dia, respectivamente. Não houve diferença de médias comparadas para o peso a desmama entre os grupamentos raciais para ambos os sexos. A média de PD, ajustado para 205 dias, de bezerras Pantaneiras e mestiças foi 148,3 kg e 161,6 kg, respectivamente. Para bezerros Pantaneiros e mestiços, os valores encontrados foram 161,7 kg e 172,3 kg, respectivamente. Os resultados encontrados foram semelhantes aos descritos na literatura para raça Nelore, principal raça bovina criada em sistema extensivo a pasto, em áreas de Cerrado. Sendo assim, considera-se que a inclusão de bovinos Pantaneiros pode ser uma alternativa viável do uso desse patrimônio genético em sistemas produtivos de cria

    Immunocytochemical demonstration of PTHrP protein in neoplastic tissue of HTLV-1 positive human adult T cell leukaemia/lymphoma: implications for the mechanism of hypercalcaemia.

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    The infiltrated tissues from seven West Indian patients with HTLV-1 positive adult T cell lymphoma/leukaemia (ATLL) have been analysed by immunocytochemical techniques for the presence of immunoreactive parathyroid hormone-related protein (PTHrP), a hormonal mediator of humoral hypercalcaemia of malignancy. Six of the seven were hypercalcaemic at some stage of the course of their disease. Four of the six evaluable patients showed evidence of specific cellular and extracellular expression of PTHrP protein in neoplastic tissues. This finding suggests that PTHrP may be involved in the production of hypercalcaemia in at least some cases of T cell lymphoma - proof of a causal relationship however must await the demonstration of tissue release of PTHrP resulting in raised circulating hormone levels

    Innovation to assess the biodiversity of indigenous potatoes: The case of the Andean Potato/INCOPA in Peru.

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