636 research outputs found

    Characterizing Brazilian climate zones for up-scaling the simulated crop yield potential.

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    ABSTRACT: Crop models are written as sets of different equations which are solved numerically. They require time series of local environmental drivers like weather conditions and constant parameters that determine sensitivity of processes to both crop state and environment. There is a hamper on the model upscaling from point to region, and the quantification of model output uncertainity at the regional scale. This paper aimed to perform a conceptual analysis of the Brazilian climate zones based on long-term uniform weather data series (air temperature, soil water deficit, rainfall and global solar radiation), were each climatic variable were spatially organized and the maps for each one were generated by a kriging interpolation. The proposed zonation seems coherent with the agroecologycal conditions observed around Brazil, and based on the biomes, there is an agreement with the main Brazilian potential vegetation types and even with the cropping systems spatial distributions. The final map might be used for ?bottom-up? upscaling approach in order to extrapolate the location specific data to a broader scale. Further work should focus in the inclusion of soil data to reach a robust zone map to support crop model outputs up-scaling, as well as in the zones validation.CBA 2013, RLAA 2013

    Additive noise properties of active matrix flatâ panel imagers

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134764/1/mp6721.pd

    Cenários futuros para cana-de-açúcar no Estado de São Paulo baseados em projeções regionalizadas de mudanças climáticas.

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    Após a divulgação das projeções de mudanças climáticas globais pelo IPCC, a avaliação de impacto das mudanças climáticas sobre a agricultura para tornouse uma necessidade para a quantificação da vulnerabilidade dos sistemas agrícolas. Este trabalho teve como objetivo simular cenários futuros para a cana-de-açúcar no Estado de São Paulo em função de cenários regionalizados de projeções climáticas, utilizando um banco de dados de 78 estações meteorológicas com séries de, pelo menos, nove anos. Para cada estação meteorológica foi associado um determinado perfil do solo e todas as séries foram expandidas para 30 anos utilizando geradores de dados. As simulações foram feitas para a variedade RB72454, considerando dois cenários futuros de mudanças climáticas para 2040. Os resultados mostraram elevação na produtividade média do Estado, com ganho de até 6% de produção total no cenário pessimista para 2040. Para o cenário otimista, o efeito sobre a produção de cana-de-açúcar seria pequeno, com perspectivas de ganhos no rendimento áreas cultivadas com solos argilosos, além de uma tendência de migração para a região Sul do Estado.CBA 2009

    Avaliação do modelo CANEGRO/DSSAT para quatro cultivares de cana-de-açúcar.

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    A parametrização do modelo DSSAT/CANEGRO para a realidade brasileira é de grande importância para a obtenção de uma ferramenta para o monitoramento de safras agrícolas e para a elaboração de cenários agrícolas futuros. O presente trabalho enfocou as cultivares R570, NCo376, RB72-454 e SP83-2847 nas condições de Piracicaba/SP. Os dados biométricos foram coletados no Centro de Tecnologia Canavieira, comparando-se os valores observados com as simulações para as seguintes variáveis: perfilhamento, altura de colmo, IAF, número de folhas verdes; e a fitomassa da parte aérea. O modelo apresentou resultados satisfatórios para todas as cultivares testadas, com exceção da NCo376, para a qual houve subestimativa da massa seca da parte aérea (-32%) e índice de área foliar (-13%).CBA 2009

    Magnetic and structural properties of the iron silicide superconductor LaFeSiH

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    The magnetic and structural properties of the recently discovered pnictogen/chalcogen-free superconductor LaFeSiH (Tc10T_c\simeq10~K) have been investigated by 57^{57}Fe synchrotron M{\"o}ssbauer source (SMS) spectroscopy, x-ray and neutron powder diffraction and 29^{29}Si nuclear magnetic resonance spectroscopy (NMR). No sign of long range magnetic order or local moments has been detected in any of the measurements and LaFeSiH remains tetragonal down to 2 K. The activated temperature dependence of both the NMR Knight shift and the relaxation rate 1/T11/T_1 is analogous to that observed in strongly overdoped Fe-based superconductors. These results, together with the temperature-independent NMR linewidth, show that LaFeSiH is an homogeneous metal, far from any magnetic or nematic instability, and with similar Fermi surface properties as strongly overdoped iron pnictides. This raises the prospect of enhancing the TcT_c of LaFeSiH by reducing its carrier concentration through appropriate chemical substitutions. Additional SMS spectroscopy measurements under hydrostatic pressure up to 18.8~GPa found no measurable hyperfine field

    Defining an International Standard Set of Outcome Measures for Patients With Hip or Knee Osteoarthritis: Consensus of the International Consortium for Health Outcomes Measurement Hip and Knee Osteoarthritis Working Group

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    Objective: To define a minimum Standard Set of outcome measures and case-mix factors for monitoring, comparing, and improving health care for patients with clinically diagnosed hip or knee osteoarthritis (OA), with a focus on defining the outcomes that matter most to patients. Methods: An international working group of patients, arthroplasty register experts, orthopedic surgeons, primary care physicians, rheumatologists, and physiotherapists representing 10 countries was assembled to review existing literature and practices for assessing outcomes of pharmacologic and nonpharmacologic OA therapies, including surgery. A series of 8 teleconferences, incorporating a modified Delphi process, were held to reach consensus. Results: The working group reached consensus on a concise set of outcome measures to evaluate patients’ joint pain, physical functioning, health-related quality of life, work status, mortality, reoperations, readmissions, and overall satisfaction with treatment result. To support analysis of these outcome measures, pertinent baseline characteristics and risk factor metrics were defined. Annual outcome measurement is recommended for all patients. Conclusion: We have defined a Standard Set of outcome measures for monitoring the care of people with clinically diagnosed hip or knee OA that is appropriate for use across all treatment and care settings. We believe this Standard Set provides meaningful, comparable, and easy to interpret measures ready to implement in clinics and/or registries globally. We view this set as an initial step that, when combined with cost data, will facilitate value-based health care improvements in the treatment of hip and knee OA

    Single-shot two-dimensional full-range optical coherence tomography achieved by dispersion control

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    We present a full-range Fourier-domain optical coherence tomography (OCT) system that is capable of acquiring two-dimensional images of living tissue in a single shot. By using line illumination of the sample in combination with a two-dimensional imaging spectrometer, 1040 depth scans are performed simultaneously on a sub-millisecond timescale. Furthermore, we demonstrate an easy and flexible real-time single-shot technique for full-range (complex-conjugate cancelled) OCT imaging that is compatible with both two-dimensional as well as ultrahighresolution OCT. By implementing a dispersion imbalance between reference and sample arms of the interferometer, we eliminate the complex-conjugate signal through numerical dispersion compensation, effectively increasing the useful depth range by a factor of two. The system allows us to record 6.7 × 3.2 mm images at 5 μm depth resolution in 0.2 ms. Data postprocessing requires only 4 s. We demonstrate the capability of our system by imaging the anterior chamber of a mouse eye in vitro, as well as human skin in vivo. © 2009 Optical Society of America

    Harvesting Candidate Genes Responsible for Serious Adverse Drug Reactions from a Chemical-Protein Interactome

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    Identifying genetic factors responsible for serious adverse drug reaction (SADR) is of critical importance to personalized medicine. However, genome-wide association studies are hampered due to the lack of case-control samples, and the selection of candidate genes is limited by the lack of understanding of the underlying mechanisms of SADRs. We hypothesize that drugs causing the same type of SADR might share a common mechanism by targeting unexpectedly the same SADR-mediating protein. Hence we propose an approach of identifying the common SADR-targets through constructing and mining an in silico chemical-protein interactome (CPI), a matrix of binding strengths among 162 drug molecules known to cause at least one type of SADR and 845 proteins. Drugs sharing the same SADR outcome were also found to possess similarities in their CPI profiles towards this 845 protein set. This methodology identified the candidate gene of sulfonamide-induced toxic epidermal necrolysis (TEN): all nine sulfonamides that cause TEN were found to bind strongly to MHC I (Cw*4), whereas none of the 17 control drugs that do not cause TEN were found to bind to it. Through an insight into the CPI, we found the Y116S substitution of MHC I (B*5703) enhances the unexpected binding of abacavir to its antigen presentation groove, which explains why B*5701, not B*5703, is the risk allele of abacavir-induced hypersensitivity. In conclusion, SADR targets and the patient-specific off-targets could be identified through a systematic investigation of the CPI, generating important hypotheses for prospective experimental validation of the candidate genes
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