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1.
Geophys Res Lett ; 49(3): e2021GL096069, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35859568

RESUMO

Water storage plays an important role in mitigating heat and flooding in urban areas. Assessment of the water storage capacity of cities remains challenging due to the inherent heterogeneity of the urban surface. Traditionally, effective storage has been estimated from runoff. Here, we present a novel approach to estimate effective water storage capacity from recession rates of observed evaporation during precipitation-free periods. We test this approach for cities at neighborhood scale with eddy-covariance based latent heat flux observations from 14 contrasting sites with different local climate zones, vegetation cover and characteristics, and climates. Based on analysis of 583 drydowns, we find storage capacities to vary between 1.3 and 28.4 mm, corresponding to e-folding timescales of 1.8-20.1 days. This makes the urban storage capacity at least five times smaller than all the observed values for natural ecosystems, reflecting an evaporation regime characterized by extreme water limitation.

2.
Sci Total Environ ; 573: 1010-1020, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27607904

RESUMO

Agricultural use of plant protection products can result in exposure of bystanders, residents, operators and workers. Within the European Union (EU) FP7 project BROWSE, a tool based on a set of models and scenarios has been developed, aiming to assess the risk of exposure of humans to these products. In the present version of the tool only a first conservative tier is available for outdoor vapour exposure assessment. In the vapour exposure evaluation, the target concentrations in air at 10m distance from the edge of a treated field are calculated for specific scenarios for each EU regulatory zone. These scenarios have been selected to represent reasonable worst case volatilisation conditions. The exposure assessment is based on a series of weekly applications in a five year period to cover a wide range of meteorological conditions. The volatilisation from the crop is calculated using the PEARL model and this PEARL output provides the emission strength used as input for the short term version of the atmospheric transport model OPS. The combined PEARL-OPS model is tested against measurements from a field experiment. First results of this test show that the mean concentration level was predicted fairly well. However, sometimes the differences between observations and simulations were found to be substantial. Improvements are suggested for the vapour exposure scenarios as well as for further model development. In the current version of the BROWSE tool a simplified procedure is used to assess single and multiple applications. The actual period of application and the time of application during the day are fixed, and the growth stage of the crop cannot be taken into account. Moreover, competing processes such as penetration of the substance into the plant tissue are not considered. The effect of these factors on the target exposure concentrations is discussed.


Assuntos
Agroquímicos/análise , Poluentes Atmosféricos/análise , Exposição por Inalação/análise , Modelos Teóricos , Exposição Ocupacional/análise , Produtos Agrícolas/crescimento & desenvolvimento , União Europeia , Humanos , Características de Residência , Volatilização , Tempo (Meteorologia)
3.
Poult Sci ; 90(5): 958-64, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21489939

RESUMO

Chicks were used to determine whether dietary corn distillers dried grains with solubles (DDGS) may prevent or ameliorate Eimeria acervulina (EA) infection. The experiment had a completely randomized design with a factorial arrangement of 3 diets (inclusion of 0, 10, or 20% DDGS) × 2 challenge treatments: inoculation with distilled water or with 10(6) sporulated EA oocysts. Each treatment was replicated with 8 pens of 5 chicks each. Experimental diets were fed from 7 to 21 d of age. Inoculation occurred on d 10 of age, considered postinoculation (PI) d 0. Feed intake and BW were measured on PI d 0, 7, and 14. Excreta samples were collected on PI d 0, 5 to 10, 12, and 14 to detect oocysts. On PI d 14, mucosal samples were collected for the analysis of bacterial populations by denaturing gradient gel electrophoresis, using the V3 region of bacterial 16S ribosome. The EA challenge reduced (P < 0.001) ADG by 17%, ADFI by 12%, and G:F by 6% from PI d 0 to 7, and by smaller percentages from PI d 7 to 14. Diet and challenge treatments did not interact in the chick performance, so dietary DDGS did not alleviate EA infection. Oocysts in excreta were detected PI only in EA chicks and no dietary effects were found. Cecal bacterial population was changed (P < 0.05) by effect of dietary DDGS and EA infection. The cecal bacterial diversity among chicks within treatments and homogeneity among chicks within treatments were reduced by EA infection (P = 0.02 to 0.001) and increased by feeding 10% DDGS (diet quadratic, P < 0.001). In summary, feeding up to 20% DDGS to young chicks did not prevent or ameliorate EA infection. Changes in cecal microbiota of chicks fed 10% DDGS can be interpreted as beneficial for intestinal health.


Assuntos
Ração Animal/análise , Galinhas , Coccidiose/veterinária , Intestinos/microbiologia , Doenças das Aves Domésticas/parasitologia , Zea mays , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Eimeria , Masculino
4.
Poult Sci ; 89(12): 2634-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21076101

RESUMO

An experiment using 336 Hy-Line W-36 Single Comb White Leghorn hens was conducted to evaluate transgenic soybeans containing the gm-fad2-1 gene fragment and the gm-hra gene. Transcription of the gm-fad2-1 gene fragment results in an increased level of oleic acid (18:1) in the seed, and expression of the soybean acetolactate synthase protein (GM-HRA) encoded by the modified gm-hra gene, is used as a selectable marker during transformation. Pullets (20 wk of age) were placed in cage lots (7 hens/cage, 2 cages/lot) and were randomly assigned to 1 of 4 corn-soybean meal dietary treatments (6 lots/treatment) formulated with the following soybean meals: nontransgenic near-isoline control (control), nontransgenic commercial reference soybean meal A (92M72), nontransgenic commercial reference soybean meal B (93B15), or transgenic soybean meal produced from soybeans containing event DP-3Ø5423-1 (305423). Weeks 20 to 24 were a preconditioning period, and the 4 experimental diets were then fed from 25 to 36 wk of age. Differences between the 305423 and control group means were evaluated, with statistical significance at P < 0.05. Body weight, hen-day egg production, egg mass, feed consumption, and feed efficiency for hens fed the 305423 soybean meal were not significantly different from the respective values for hens fed diets formulated with the near-isoline soybean meal. Likewise, egg component weights, Haugh unit measures, and egg weights were similar regardless of the soybean meal source. This research indicates that performance of hens fed diets containing 305423 soybean meal, as measured by egg production and egg quality, was similar to that of hens fed diets formulated with the near-isoline control and commercial soybean meals.


Assuntos
Ração Animal , Galinhas/fisiologia , Ovos/normas , Glycine max/genética , Avaliação Nutricional , Animais , Peso Corporal , Ingestão de Energia , Feminino , Oviposição , Plantas Geneticamente Modificadas , Aumento de Peso
5.
Poult Sci ; 89(3): 539-44, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20181871

RESUMO

Three experiments were conducted to evaluate the effects of corn particle size on growth performance, ME(n), apparent total tract amino acid digestibility, and cecal microbial populations when young chicks were fed a corn-soybean meal-based diet. In all experiments, 1-d-old chicks were randomly assigned to 1 of 4 dietary treatments containing corn particle geometric mean diameters of 557, 858, 1,210, or 1,387 microm. Chicks were fed the experimental diets from 0 to 21 d posthatch and ME(n) and apparent total tract amino acid digestibility were determined at 7 and 21 d of age. When compared with the smallest geometric mean diameters of 557 microm, feeding the larger particle sizes had no effect on growth performance from 0 to 21 d in all experiments. Feeding larger corn particle sizes resulted in increases in relative gizzard weights in all experiments, with the greatest increase occurring with the 1,387-microm corn particle size. Gizzard pH was unaffected by corn particle size in all experiments. The ME(n) values and digestibility coefficients for most amino acids were higher (P < 0.05) at 21 d than at 7 d for all dietary treatments. In experiment 2, the ME(n) values showed a significant linear decrease (P < 0.007) as corn particle size increased at 7 d. The digestibility of most amino acids was unaffected by corn particle size at 7 or 21 d. Cecal lactobacilli populations were increased (P < 0.05) when the largest particle size was included in the diet. The results of these studies indicated that feeding larger particle size corn increased gizzard weight significantly but had no consistent effect on overall growth performance, ME(n), or amino acid digestibility.


Assuntos
Ração Animal/análise , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Zea mays , Envelhecimento , Fenômenos Fisiológicos da Nutrição Animal , Animais , Digestão , Feminino , Manipulação de Alimentos , Conteúdo Gastrointestinal/química , Masculino , Tamanho da Partícula
6.
Poult Sci ; 88(11): 2360-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19834087

RESUMO

Two experiments were conducted with New Hampshire x Columbian chicks fed a corn-soybean meal diet to examine the efficacy of varying levels and combinations of Grobiotic P (GB), a prebiotic-type product that contains dairy and yeast fractions and dried fermentation extracts, gluconic acid, and yeast cell wall (YCW) on growth performance, nutrient digestibility, and cecal microbial populations. In experiment 1, chicks were allowed ad libitum access to a corn-soybean meal basal diet or the basal diet supplemented with 2 or 4% GB, 1.5 or 3% gluconic acid, 0.2% YCW, or various 2-way combinations of the supplements in place of dextrose and arenaceous flour. In experiment 2, the same supplement combinations were used as in experiment 1; however, the 3% gluconic acid supplement was eliminated. In both experiments, supplementing GB, YCW, or 1.5% gluconic acid to the diet had no consistent effect on growth performance except that the weight gain was depressed (P < 0.05) when the chicks were fed a diet containing 3% gluconic acid. Chicks fed diets containing 2 or 4% GB combinations showed a significant increase (P < 0.05) in ME(n) at 21 d when compared with chicks fed the basal diet. For amino acid (AA) digestibility, 2% GB combined with 0.2% YCW or 1.5% gluconic acid resulted in a reduction (P < 0.05) in AA digestibility at 7 d; however, at 21 d, these combinations increased (P < 0.05) digestibility of all AA. There was no consistent effect of dietary treatment on cecal bifidobacteria, lactobacilli, Escherichia coli, or Clostridium perfringens populations or cecal pH. These experiments indicated that diets containing GB generally increased ME(n) and AA digestibility at 21 d and that the prebiotic combinations had no consistent effects on cecal microbial populations.


Assuntos
Ceco/microbiologia , Parede Celular , Galinhas/crescimento & desenvolvimento , Digestão/fisiologia , Gluconatos/farmacologia , Probióticos/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Saccharomyces cerevisiae , Aumento de Peso
7.
Poult Sci ; 87(3): 475-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18281573

RESUMO

An experiment using 216 Hy-Line W-36 pullets was conducted to evaluate transgenic maize grain containing the cry34Ab1 and cry35Ab1 genes from a Bacillus thuringiensis (Bt) strain and the phosphinothricin ace-tyltransferase (pat) gene from Streptomyces viridochromogenes. Expression of the cry34Ab1 and cry35Ab1 genes confers resistance to corn rootworms, and the pat gene confers tolerance to herbicides containing glufosinate-ammonium. Pullets (20 wk of age) were placed in cage lots (3 hens/cage, 2 cages/lot) and were randomly assigned to 1 of 3 corn-soybean meal dietary treatments (12 lots/treatment) formulated with the following maize grains: near-isogenic control (control), conventional maize, and transgenic test corn line 59122 containing event DAS-59122-7. Differences between 59122 and control group means were evaluated with statistical significance at P < 0.05. Body weight and gain, egg production, egg mass, and feed efficiency for hens fed the 59122 corn were not significantly different from the respective values for hens fed diets formulated with control maize grain. Egg component weights, Haugh unit measures, and egg weight class distribution were similar regardless of the corn source. This research indicates that performance of hens fed diets containing 59122 maize grain, as measured by egg production and egg quality, was similar to that of hens fed diets formulated with near-isogenic corn grain.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Galinhas/crescimento & desenvolvimento , Oviposição/fisiologia , Plantas Geneticamente Modificadas , Zea mays/genética , Ração Animal , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias , Toxinas Bacterianas , Composição Corporal , Ovos/normas , Endotoxinas , Feminino , Proteínas Hemolisinas , Controle Biológico de Vetores , Distribuição Aleatória , Aumento de Peso
8.
Environ Pollut ; 146(3): 726-35, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16766104

RESUMO

A multiplicative and a semi-mechanistic, BWB-type [Ball, J.T., Woodrow, I.E., Berry, J.A., 1987. A model predicting stomatal conductance and its contribution to the control of photosynthesis under different environmental conditions. In: Biggens, J. (Ed.), Progress in Photosynthesis Research, vol. IV. Martinus Nijhoff, Dordrecht, pp. 221-224.] algorithm for calculating stomatal conductance (g(s)) at the leaf level have been parameterised for two crop and two tree species to test their use in regional scale ozone deposition modelling. The algorithms were tested against measured, site-specific data for durum wheat, grapevine, beech and birch of different European provenances. A direct comparison of both algorithms showed a similar performance in predicting hourly means and daily time-courses of g(s), whereas the multiplicative algorithm outperformed the BWB-type algorithm in modelling seasonal time-courses due to the inclusion of a phenology function. The re-parameterisation of the algorithms for local conditions in order to validate ozone deposition modelling on a European scale reveals the higher input requirements of the BWB-type algorithm as compared to the multiplicative algorithm because of the need of the former to model net photosynthesis (A(n)).


Assuntos
Algoritmos , Oxidantes Fotoquímicos/toxicidade , Ozônio/toxicidade , Folhas de Planta/fisiologia , Betula/efeitos dos fármacos , Betula/fisiologia , Ritmo Circadiano , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/fisiologia , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Fagus/efeitos dos fármacos , Fagus/fisiologia , Modelos Biológicos , Folhas de Planta/efeitos dos fármacos , Estações do Ano , Triticum/efeitos dos fármacos , Triticum/fisiologia , Vitis/efeitos dos fármacos , Vitis/fisiologia
12.
Healthc Financ Manage ; 51(7): 41-2, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10168436

RESUMO

Managing patient and physician demand for resources is crucial to the cost-effective delivery of high-quality patient care. This task is complicated by the expectations for better medical care that patients and physicians developed before prospective payment systems were instituted. The use of clinical decision support tools, which may combine appropriateness criteria with practice guidelines, can help manage demand rationally, control costs, and minimize concerns about overutilization and underutilization of healthcare services.


Assuntos
Técnicas de Apoio para a Decisão , Necessidades e Demandas de Serviços de Saúde/organização & administração , Programas de Assistência Gerenciada/estatística & dados numéricos , Análise Custo-Benefício , Programas de Assistência Gerenciada/organização & administração , Avaliação de Resultados em Cuidados de Saúde , Guias de Prática Clínica como Assunto , Qualidade da Assistência à Saúde , Encaminhamento e Consulta , Estados Unidos , Revisão da Utilização de Recursos de Saúde
13.
Med Interface ; 10(6): 70-2, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10169011

RESUMO

Gatekeepers are currently being asked to do more, including managing referrals to specialists. When a physician appropriately continues care at the primary level in order to pursue a more conservative course of treatment, prescription drugs often play an important role. According to the author, physicians can easily turn to utilization management, not disease management programs, for clinical guidance. Adding a pharmaceutical component with clear indications for drug use to the clinical decision support criteria or guidelines used by physicians helps them to decide when a trial of first-line pharmaceutical management is warranted and at what point to switch to an alternative drug therapy or to refer.


Assuntos
Técnicas de Apoio para a Decisão , Tratamento Farmacológico/normas , Programas de Assistência Gerenciada/normas , Guias de Prática Clínica como Assunto , Revisão da Utilização de Recursos de Saúde , Controle de Custos , Análise Custo-Benefício , Gerenciamento Clínico , Prescrições de Medicamentos , Tratamento Farmacológico/estatística & dados numéricos , Medicina de Família e Comunidade , Humanos , Encaminhamento e Consulta/normas , Encaminhamento e Consulta/estatística & dados numéricos , Estados Unidos
16.
Arch Biochem Biophys ; 316(1): 523-8, 1995 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-7840661

RESUMO

A novel series of nonpeptidic compounds that contain a biphenyl carboxylic acid group have been shown to inhibit HIV-1 protease. The active compounds, most of which are highly soluble, have IC50 values in the range of 3.4-74 microM. The structure-inhibitory activity relationship demonstrates the necessity of the biphenyl carboxylic acid group for inhibition, which is enhanced by the presence of a sulfone group and by halogenation of an adjacent phenyl group. A double reciprocal plot of inhibition data on two of the compounds clearly shows that the inhibition occurs in a competitive manner, with Ki values of 1.1 and 3.4 microM. Inhibition by several of the compounds was found to be reversible and fast-binding, while one of the biphenyl carboxylic acids inhibits in a reversible slow-binding manner. Time-dependent inhibition studies were conducted on this compound, and it was determined to have the kinetic values of kon = 0.18 microM-1min-1, koff = 9.7 x 10(-2)min-1, and Ki = 0.14 microM. Thus, the slow-binding inhibitor is the most potent in the series. Molecular modeling has provided information on a possible binding mode for two different biphenyl carboxylic acid inhibitors of HIV-1 protease.


Assuntos
Compostos de Bifenilo/farmacologia , Ácidos Carboxílicos/farmacologia , Inibidores da Protease de HIV/farmacologia , HIV-1/enzimologia , Sequência de Aminoácidos , Sítios de Ligação , Compostos de Bifenilo/química , Ácidos Carboxílicos/química , Simulação por Computador , Desenho de Fármacos , Inibidores da Protease de HIV/química , Inibidores da Protease de HIV/classificação , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Recombinantes/efeitos dos fármacos , Solubilidade
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