Evaporation of the soil water in response to the amount of straw and evaporative demand.

Título em português: Evaporação da água do solo em resposta à quantidade de palha e à demanda evaporativa

Volatile fingerprinting of ripened cheese for authentication and characterisation of different dairy systems

Authentication of dairy systems is of growing interest for the dairy industry and we investigated the potentiality of using volatile fingerprinting of ripened cheeses by proton transfer reaction time-of-flight mass spectrometry. A total of 1,075 individual model cheeses made from milk of individual Brown Swiss cows of 72 farms were analysed. Using a linear discriminant analysis, cows and herds were assigned to 3 or 5 dairy systems differing in management, available facilities, and diets. We obtained variable discrimination abilities (up to 77% of correct classification of cheeses and 70% of farms with cross-validation). We found m/z 61,028 (acetic acid), 109,070 (pyrazine), and m/z 137,132 (terpene) characterising model cheeses from traditional dairy systems and m/z 71,086 (3-methyl-butan-1-ol, 3-methyl-3-buten-1-ol, pentan-1-ol), m/z 101,097 (hexan-2-one, hexanal), m/z 123,117 (nonenal), m/z 129,127 (octan-1-one, octanal), and two unidentified peaks m/z 83,071 and m/z 93,090 characterising model cheeses from the modern farms. In conclusion, it seems possible to discriminate between a range of dairy systems using fast volatile fingerprinting of ripened cheeses but a proper validation of results obtained is needed.Highlights Mass spectrometry technique (PTR-ToF-MS) was able to discriminate between dairy systems. We found m/z 61,028 (acetic acid), 109,070 (pyrazine), and m/z 137,132 (terpene) characterising model cheeses from traditional dairy systems. We found m/z 71,086 (3-methyl-butan-1-ol, 3-methyl-3-buten-1-ol, pentan-1-ol), m/z 101,097 (hexan-2-one, hexanal), m/z 123,117 (nonenal), m/z 129,127 (octan-1-one, octanal), and two unidentified peaks m/z 83,071 and m/z 93,090 characterising model cheeses from the modern farms

A multi-layer edge-on single photon counting silicon microstrip detector for innovative techniques in diagnostic radiology

A three-layer detector prototype, obtained by stacking three edge-on single photon counting silicon microstrip detectors, has been developed and widely tested. This was done in the framework of the Synchrotron Radiation for Medical Physics/Frontier Radiology (SYRMEP/FRONTRAD) collaboration activities, whose aim is to improve the quality of mammographic examinations operating both on the source and on the detector side. The active surface of the device has been fully characterized making use of an edge-scanning technique and of a well-collimated laminar synchrotron radiation beam. The obtained data (interlayer distances, channel correspondence, etc.) have then been used to combine information coming from each detector layer, without causing any loss in spatial and contrast resolution of the device. Contrast and spatial resolution have also been separately evaluated for each detector layer. Moreover, imaging techniques (phase contrast, refraction, and scatter imaging), resulting in an increased visibility of low absorbing details, have been implemented, and their effectiveness has been tested on a biological sample. Finally, the possibility of simultaneously acquiring different kind of images with the different detector layers is discussed. This would result in maximizing the information extracted from the sample, while at the same time the high absorption efficiency of the detector device would allow a low dose delivery

Taking the pulse of snowmelt: in situ sensors reveal seasonal, event and diurnal patterns of nitrate and dissolved organic matter variability in an upland forest stream

Highly resolved time series data are useful to accurately identify the timing, rate, and magnitude of solute transport in streams during hydrologically dynamic periods such as snowmelt. We used in situ optical sensors for nitrate (NO3 −) and chromophoric dissolved organic matter fluorescence (FDOM) to measure surface water concentrations at 30 min intervals over the snowmelt period (March 21–May 13, 2009) at a 40.5 hectare forested watershed at Sleepers River, Vermont. We also collected discrete samples for laboratory absorbance and fluorescence as well as δ18O–NO3 − isotopes to help interpret the drivers of variable NO3 − and FDOM concentrations measured in situ. In situ data revealed seasonal, event and diurnal patterns associated with hydrological and biogeochemical processes regulating stream NO3 − and FDOM concentrations. An observed decrease in NO3 − concentrations after peak snowmelt runoff and muted response to spring rainfall was consistent with the flushing of a limited supply of NO3 − (mainly from nitrification) from source areas in surficial soils. Stream FDOM concentrations were coupled with flow throughout the study period, suggesting a strong hydrologic control on DOM concentrations in the stream. However, higher FDOM concentrations per unit streamflow after snowmelt likely reflected a greater hydraulic connectivity of the stream to leachable DOM sources in upland soils. We also observed diurnal NO3 − variability of 1–2 μmol l−1 after snowpack ablation, presumably due to in-stream uptake prior to leafout. A comparison of NO3 − and dissolved organic carbon yields (DOC, measured by FDOM proxy) calculated from weekly discrete samples and in situ data sub-sampled daily resulted in small to moderate differences over the entire study period (−4 to 1% for NO3 − and −3 to −14% for DOC), but resulted in much larger differences for daily yields (−66 to +27% for NO3 − and −88 to +47% for DOC, respectively). Despite challenges inherent in in situ sensor deployments in harsh seasonal conditions, these data provide important insights into processes controlling NO3 − and FDOM in streams, and will be critical for evaluating the effects of climate change on snowmelt delivery to downstream ecosystems

Manipulation of ovarian and uterine function to increase conception rates in cattle.

In cattle, embryonic and fetal losses are the major causes of reproductive failureo Losses associated with failure in the process of maternal recognition of pregnancy can amount to as much as 30%0 Successful establishment of pregnancy depends on a delicate balance between luteolytic mechanisms inherent to the endometrium at the end of diestrus and antiluteolytic mechanisms, orchestrated by the conceptus to change endometrial function and, ultimately, block luteolysis. Antiluteolytic strategies are pharmacological, mechanical, nutritional and management manipulations of the process of maternal recognition of pregnancy that aim to increase the probability of successful gestations. Objective of the present paper is to review the recent literature on antiluteolytic strategies in cattle. Specifically, we focused on strategies to stimulate production of progesterone, strategies to reduce production of estradiol and other sttategies. Future directions for research in this area are proposedo

Estratégias para reduzir a mortalidade embrionária em bovinos: I. Alternativas farmacológicas para otimizar a função luteínica de vacas de corte.

A mortalidade embrionária precoce é a maior causa de perdas reprodutivas em bovinos europeus criados no hemisfério norte. Uma vez que a eficiência reprodutiva do gado de corte nacional é baixa, conjetura-se que tais perdas também ocorram com bovinos de corte zebu criados no Brasil. Para aprofundar os conhecimentos sobre esse tema e propor possíveis estratégias que minimizem as perdas de prenhez, foi desenvolvido na Embrapa Pecuária Sudeste o projeto ?Mortalidade embrionária em bovinos e estratégias para a sua redução? que, além de ter como objetivo principal a determinação das taxas e da cronologia das perdas reprodutivas em vacas nelore inseminadas artificialmente, estabeleceu como meta o desenvolvimento de uma alternativa farmacológica de otimização da função luteínica de vacas de corte. Para tanto, avaliou-se o efeito de diferentes protocolos de suporte hormonal sobre as funções luteínicas e foliculares de vacas das raças Nelore e Red Angus. O alcance dessa meta, ou seja, o desenvolvimento de um protocolo de otimização da função luteínica de vacas de corte disponibiliza uma prática pecuária inovadora, a qual está descrita detalhadamente no presente Boletim de Pesquisa e Desenvolvimento.bitstream/item/43525/1/Boletim26.pd

A massively parallel exponential integrator for advection-diffusion models

This work considers the Real Leja Points Method (ReLPM) for the exponential integration of large-scale sparse systems of ODEs, generated by Finite Element or Finite Difference discretizations of 3-D advection-diffusion models. We present an efficient parallel implementation of ReLPM for polynomial interpolation of the matrix exponential propagators. A scalability analysis of the most important computational kernel inside the code, the parallel sparse matrix\u2013vector product, has been performed, as well as an experimental study of the communication overhead. As a result of this study an optimized parallel sparse matrix\u2013vector product routine has been implemented. The resulting code shows good scaling behavior even when using more than one thousand processors. The numerical results presented on a number of very large test cases gives experimental evidence that ReLPM is a reliable and efficient tool for the simulation of complex hydrodynamic processes on parallel architectures