1,263 research outputs found
Factors affecting the patterns of total amount and proportions of leukocytes in Bovine milk
Differential leukocyte count (DSCC) in milk is considered important to improve knowledge of udder immune response. The investigations on milk DSCC were limited by the techniques available until recently, when a high-throughput tool to perform DSCC opened the way to explore these factors in rapid and economically sustainable ways. We hypothesized that DSCC alone does not fully describe the pattern of these cells, since the total amount is also influenced by milk yield and SCC. Therefore, this study was designed to describe DSCC and total amount of different leukocytes in milk during the course of lactation in cows differing in parity and in levels of SCC. This study considered 17,939 individual milk tests from 12 dairy herds in Lombardy Region, where DCC testing was applied in the period of February 2018\u2013December 2019 (23 months). The samples were divided into two subsets\u2014\u201chealthy\u201d (HS) with SCC 64200,000 cells/mL and \u201cinflamed\u201d (IS) with SCC >200,000 cells/mL. Cow in HS have a P + LT average between 5.0
7 108 and 3.0
7 109 cells. In IS cows, the values were 1.6
7 1010 and 2.5
7 1010. Therefore, the presence of a well-defined inflammatory process increased the overall amount of polymorphonuclear neutrophils (PMN) and lymphocytes (LYM) of 1 log, from 1
7 109 to 1
7 1010. The assessment of the total amount of PMN and LYM, to our knowledge, have never been reported in scientific literature; the values observed may be proposed as benchmarks for studies on udder immune response. When data were analyzed by days in milk (DIM),they showed that cows in first and second lactation have a significantly lower amount of PMN + LYM, when compared to cows in third and higher lactation. However, these differences are numerically not very large (7%), and suggest that, in healthy animals, the number of immune cells is kept as constant as possible. In IS, the analysis of trends based on DIM showed that both DSCC and P + LT have a significant negative trend. These data suggest that only in this group, the presence of high SCC as lactation proceeds is associated with a progressive increase in the number of macrophages. To the best of our knowledge, this is the first study describing the pattern of DSCC and the total amount of PMN + LYM in relation to parity, days in milk, and SCC, and it may be considered as the first contribution in the investigation on mammary gland immune response by the means of differential cell counts in milk
A diversificação das receitas bancárias: seu impacto sobre o risco e o retorno dos bancos brasileiros
O objetivo deste estudo é determinar o impacto da diversificação das receitas bancárias sobre o risco e o retorno dos bancos brasileiros. Essa estratégia foi adotada por bancos em diversos países, inclusive no Brasil. Em 2003, as receitas noninterest (não decorrentes de juros) representavam 17,80% da receita operacional dos bancos analisados e, em 2014, essa participação havia aumentado para 27,40%. Embora muitos estudos tenham abordado a questão para bancos americanos, europeus e asiáticos, este tema ainda não foi abordado para uma amostra de bancos brasileiros. Como o setor bancário é uma variável crucial à estabilidade do sistema financeiro, é importante estudar os fatores que afetam o risco e o retorno dos bancos. Analisamos a amostra para o período entre 2003 e 2014, utilizando dados em painel dinâmico através do Método Generalizado dos Momentos para abordar questões de endogeneidade, heterocedasticidade e autocorrelação. Nossos principais resultados mostram que as receitas noninterest possuem um papel importante no desempenho dos bancos estudados; nossa análise das atividades de intermediação financeira mostrou que as operações de crédito produziram melhores resultados do que as atividades de negociação de títulos. Além disso, confirmando as hipóteses propostas, as receitas noninterest apresentaram, de maneira geral, um impacto positivo sobre o retorno e o retorno ajustado ao risco nos bancos estudados. Entretanto, ao contrário do que esperávamos, as receitas noninterest mostraram uma relação positiva com o risco desses bancos (embora estatisticamente não significativa). É importante destacar as variáveis de controle, ou seja, a taxa de juros real, o PIB e o crescimento bancário, as quais foram relevantes para a determinação do desempenho dos bancos.The present study aims to determine the impact of bank revenue diversification on Brazilian banks’ risk and return. This strategy has been adopted by banks in several countries, including Brazil. In 2003, noninterest income accounted for 17.80% of the operating revenue of the banks analyzed, and in 2014, this share increased to 27.40%. While many studies have addressed the subject in American, European and Asian banks, it still has not been approached in a sample of Brazilian banks. Since the banking industry is a key variable for the financial system’s stability, it is important to study the factors that affect banks’ risk and return. We analyzed the sample for the period from 2003 to 2014, using dynamic panel data GMM (Generalized Method of Moments) to address endogeneity, heteroscedasticity and autocorrelation problems. Our main results show that noninterest income has a major role in the performance of the banks studied; our analysis of financial intermediation activities showed that loan operations produced better results than trading. Moreover, confirming the hypotheses proposed, noninterest income showed a generally positive impact on return and risk adjusted return for the banks studied. However, against our expectation, noninterest income showed a positive relationship with the risk of these banks (although not statistically significant). It is worth highlighting the control variables, i.e., real interest rate, GDP and bank growth, which were relevant in determining bank performance
Neutron sources based on medical Linac
The paper proposes the study of a novel photo-neutron source based on a medical high-energy electron Linac. Previous studies by the authors already demonstrated the possibility to obtain with this technique a thermal neutron flux of the order of 107 cm−2 s−1. This paper shows possible Linac’s setup and a new photo-converter design to reach a thermal neutron flux around 6 × 107 cm−2 s−1,
keeping a reasonable high quality of the beam with respect to fast neutron and gamma contaminations
Possible Approach to Esophageal Lung with Long Tracheobronchial Gap
Esophageal lung is a rare bronchopulmonary foregut malformation characterized by an anomalous origin of one of the main bronchi which arises from the esophagus. Less than 30 cases are reported in the literature. Therefore, there are no standardized guidelines for the treatment of this condition. We report a case of right esophageal lung diagnosed in a neonate. The patient was treated with thoracoscopic closure of the ectopic main bronchus in the neonatal period, followed by delayed pneumonectomy at 5 months of age. No prosthetic substitute was implanted in the ipsilateral hemithorax after pneumonectomy. The patient is now 4 years old and doing well, postpneumonectomy syndrome was never observed. Our strategy and the possible alternatives are discussed here
Differential Somatic Cell Count as a Marker for Changes of Milk Composition in Cows with Very Low Somatic Cell Count
The recent availability of a high-throughput milk analyzer performing a partial differential somatic cell count (DSCC) opened new opportunities in investigations on bovine udder health. This analyzer has a potential limitation on the accuracy of measurements when the somatic cell count (SCC) is below 50,000 cells/mL, values characterizing a good proportion of lactating cows in many herds. We obtained data for cows below this threshold, assessed the repeatability of these measurements and investigated the relationship between DSCC and udder health, milk composition and yield. Overall, 3022 cow milk test records performed on a Fossomatic™ 7/DC (Foss A/S, Hillerød, Denmark) were considered; 901 of them had an SCC ≤ 50,000 cells/mL. These latter samples were analyzed by qPCR to identify the presence of bacteria. Overall, 20.75% of the samples (187) were positive. However, the health status did not have any significant association with DSCC. The analysis of the association of DSCC on milk fat, protein and casein showed a significant decrease in their proportions as the DSCC increased, whereas it was not observed for milk yield and lactose. Therefore, DSCC in very low SCC cows may be suggested as a marker to identify early changes in milk composition
Herbicides in the Soil Environment: Linkage between Bioavailability and Microbial Ecology
Modern agriculture relies heavily on herbicides for the control of weeds in crops and pastures to maximize yields and economical benefits to sustain an increasing world population. The introduction of herbicide-resistant traits in several crops, such as glyphosate-resistant soybean, maize and canola, has further increased herbicide consumption worldwide. The environmental fate of herbicides is a matter of recent concern given that only a small fraction of the chemicals reaches the target organisms. While most herbicides are not intentionally applied onto soil, they can enter the soil environment from direct interception of spray by the soil surface during early season or post-harvest applications, from runoff or leaching of the herbicide from vegetation and/or from dead plant material. This chapter will present aspects of the behavior of herbicides in soils, focusing on soil retention and microbial degradation as main factors controlling persistence. The potential impact of herbicides on non-target soil microbes, on their processes and interactions, will be also discussed. The enormous variety of herbicides commercially available today makes it impossible to review all of them. Thus, this work will focus on some of the herbicides most used in the (semiarid) Pampa region of Argentina and worldwide (i.e., glyphosate, 2,4-dichlorophenoxyacetic acid, atrazine, metsulfuron-methyl), based on our own research data. Adsorption to soil is of critical importance for the regulation of herbicide persistence and mobility throughout the environment because sorption processes control the amount of herbicide present in the soil solution. These processes are dependent on several factors related to soil characteristics such as mineral composition, organic matter content, soil solution chemistry and to chemical characteristics of the herbicide. Soil-bound herbicide or residues are temporarily inactivated, which prevents harmful effects on soil biota but also makes them less bio-available for microbial degradation because most microbial species are not able to utilize herbicides in the sorbed state. Herbicide degradation will be discussed both in terms of their use as carbon and nutrient sources. Most isolated herbicide-degrading microorganisms belong to bacterial species, but fungi are also well-known for their capacity to degrade complex substrates, and may be more important than present isolation approaches have suggested. Differential toxicity of herbicides to soil microorganisms may alter community structure, including potential increases in plant or animal pathogens. Herbicides may also cause changes in microbial community function and concomitant impacts on soil health and ecosystem processes.Fil: Zabaloy, Maria Celina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Zanini, Graciela Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Bianchinotti, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Gomez, Marisa Anahi. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Garland, Jay L.. Dynamac Corporation; Estados Unido
Cross-sectional study on the prevalence of contagious pathogens in bulk tank milk and their effects on somatic cell counts and milk yield
Data on the prevalence of major contagious pathogens in bulk tank milk (BTM) in Italy are generally not available. The availability of Real-Time PCR procedures (qPCR) to perform BTM analysis by represents an important step to define herd health status. Therefore, a cross-sectional epidemiological study was designed to assess the prevalence of contagious pathogens and Prototheca spp in BTM samples. The study was performed on 581 herds from four districts in the west Lombardy region of Italy. Additionally, the relationship between pathogens in BTM and SCC or milk yield; the presence of an association between four risk factors (district, herd size, average milk yield and SCC) with pathogens in BTM were assessed. The overall data showed that S. aureus was recovered in 42% of the herds, Str. agalactiae in 10%, Prototheca spp in 11% and M. bovis in 1.5% of the herds. The GLM model applied showed a significant influence of BTM results, district, herd size and their interactions on SCC and on milk yield variance. Particularly, S. aureus or Str. agalactiae have a significant effect on milk yield variability and, in a lesser extent, on SCC. The very high prevalence of contagious pathogens significantly affects milk characteristics and yield, thus affecting economic sustainability of the herds, and suggests the need to implement control programmes to decrease the prevalence of contagious pathogens, This will also allow to decrease the use of antimicrobials and to improve cow welfare
Radioprotection calculations for the TRADE experiment
The TRADE project is based on the coupling of, in a sub-critical configuration, of a 115 MeV, 2 mA proton cyclotron with a TRIGA research reactor at the ENEA Casaccia centre (Rome). Detailed radioprotection calculations using the FLUKA and EA-MC Monte Carlo codes were performed during the feasibility study. The study concentrated on dose rates due to beam losses in normal operating conditions and in the calculation of activation in the most sensitive components of the experiment. Results show that a shielding of 1.4 m of barytes concrete around the beam line will be sufficient to maintain the effective doses below the level of 10 Mu Sv/h, provided that the beam losses are at the level of 10 nA/m. The activation level around the beam line and in the water will be negligible, while the spallation target will reach an activation level comparable to the one of a fuel element at maximum burnup
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