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91.
Matthew?W.?MitchellEmail author Marcia?L.?Gumpertz 《Journal of Agricultural, Biological & Environmental Statistics》2003,8(3):310-327
The Japanese RiceFACE (Free-Air CO2 Enrichment) project was a three-year investigation into the effect of elevated CO2 on rice. Four rings were built to emit elevated levels of CO2. The aim of the FACE system is to provide a level of CO2 enrichment 200 ppm above tmbient throughout the plot, without changing any other aspect of the microclimate within the plot.
However, there can be substantial spatial variation in the CO2 level from the center to the edges of the plots. One of our main objectives was to predict the seasonal mean levels of CO2 for multiple subregions within the plots. However, the dataset was very large and followed a nonnormal distribution. Furthermore,
the mean and variance were nonstationary. To overcome these difficulties daily means were used rather than individual measurements,
the mean was modeled with multiple covariates that varied over both time and space, and the variance was modeled as an increasing
function of the square of the distance from the center of the plot. A separable space-time covariance structure was used,
and estimation was performed using nonlinear methods, REML, and EGLS. Finally, cross-validation was used to assess the validity
of the model. 相似文献
92.
Kempf S Srama R Postberg F Burton M Green SF Helfert S Hillier JK McBride N McDonnell JA Moragas-Klostermeyer G Roy M Grün E 《Science (New York, N.Y.)》2005,307(5713):1274-1276
During Cassini's approach to Saturn, the Cosmic Dust Analyser (CDA) discovered streams of tiny (less than 20 nanometers) high-velocity (approximately 100 kilometers per second) dust particles escaping from the saturnian system. A fraction of these impactors originated from the outskirts of Saturn's dense A ring. The CDA time-of-flight mass spectrometer recorded 584 mass spectra from the stream particles. The particles consist predominantly of oxygen, silicon, and iron, with some evidence of water ice, ammonium, and perhaps carbon. The stream particles primarily consist of silicate materials, and this implies that the particles are impurities from the icy ring material rather than the ice particles themselves. 相似文献
93.
Rafael V. A. Zafalon Larissa W. Risolia Vivian Pedrinelli Thiago H. A. Vendramini Roberta B. A. Rodrigues Andressa R. Amaral Marcia M. Kogika Marcio A. Brunetto 《Journal of animal physiology and animal nutrition》2020,104(1):322-342
Due to the presence of receptors in the cells of numerous body tissues, vitamin D is associated with several physiological functions that go beyond calcium and phosphorus homoeostasis and control of bone metabolism in the body. In humans, several studies have associated lower vitamin D concentrations with numerous diseases, such as cancer, heart disease, autoimmune diseases and infectious diseases, and also with an increase in the total mortality rate of the population. Recently, this nutrient started to gain importance in veterinary medicine, and several articles have shown a correlation between low vitamin D status and diseases unrelated to bone metabolism. The present review aims to highlight the recent publications that investigated this relationship, bringing the evidence that exists so far in dogs and cats. 相似文献
94.
Kunde VG Flasar FM Jennings DE Bézard B Strobel DF Conrath BJ Nixon CA Bjoraker GL Romani PN Achterberg RK Simon-Miller AA Irwin P Brasunas JC Pearl JC Smith MD Orton GS Gierasch PJ Spilker LJ Carlson RC Mamoutkine AA Calcutt SB Read PL Taylor FW Fouchet T Parrish P Barucci A Courtin R Coustenis A Gautier D Lellouch E Marten A Prangé R Biraud Y Ferrari C Owen TC Abbas MM Samuelson RE Raulin F Ade P Césarsky CJ Grossman KU Coradini A 《Science (New York, N.Y.)》2004,305(5690):1582-1586
The Composite Infrared Spectrometer observed Jupiter in the thermal infrared during the swing-by of the Cassini spacecraft. Results include the detection of two new stratospheric species, the methyl radical and diacetylene, gaseous species present in the north and south auroral infrared hot spots; determination of the variations with latitude of acetylene and ethane, the latter a tracer of atmospheric motion; observations of unexpected spatial distributions of carbon dioxide and hydrogen cyanide, both considered to be products of comet Shoemaker-Levy 9 impacts; characterization of the morphology of the auroral infrared hot spot acetylene emission; and a new evaluation of the energetics of the northern auroral infrared hot spot. 相似文献
95.
Adapting family life cycle theory to include pets provides veterinarians with a framework for understanding and reinforcing the human-animal bond. The family genogram with pets is a practice tool that identifies all people and pets in the family, enhancing the practice of One Health at the community level. 相似文献
96.
Grazziotin AL Santos AP Guimaraes AM Mohamed A Cubas ZS de Oliveira MJ dos Santos LC de Moraes W Vieira RF Donatti L de Barros Filho IR Biondo AW Messick JB 《Veterinary microbiology》2011,152(3-4):415-419
Hemotrophic mycoplasmas (hemoplasmas) are bacteria that attach to red blood cells of mammals, leading to acute and/or subclinical disease in infected animals. It has been suggested that Mycoplasma ovis, a hemoplasma that infects sheep and goats worldwide, may also infect deer. The aim of this study was to evaluate whether South American deer are infected with M. ovis. EDTA-anticoagulated blood samples from a herd of 32 captive South American deer were collected. DNA extraction of blood samples was performed followed by PCR amplification of the 16S and 23S rRNA genes, and sequencing of products. Using M. ovis PCR, 27/31 (87%) were positive, including 21/22 Mazama nana; 2/3 Mazama americana and 4/6 Blastocerus dichotomus. Sequencing of the nearly entire 16S rRNA gene of 26/27 positive samples showed 98.2-98.8% identity to M. ovis of sheep (GenBank, AF338268) and 98.6-99.4% identity to M. ovis-like of a fawn (FJ824847); the 23S rRNA gene from one of these isolates and the fawn's had 97.6% identity. The remaining isolate had just 94.9% identity to the 16S rRNA gene of M. ovis and only 89.4% identity to the 23S rRNA gene of the fawn's M. ovis. This is the first report of M. ovis in captive South American deer, revealing a high prevalence of hemoplasma infection in these animals. 相似文献
97.
98.
99.
Gilbert NC Bartlett SG Waight MT Neau DB Boeglin WE Brash AR Newcomer ME 《Science (New York, N.Y.)》2011,331(6014):217-219
The synthesis of both proinflammatory leukotrienes and anti-inflammatory lipoxins requires the enzyme 5-lipoxygenase (5-LOX). 5-LOX activity is short-lived, apparently in part because of an intrinsic instability of the enzyme. We identified a 5-LOX-specific destabilizing sequence that is involved in orienting the carboxyl terminus, which binds the catalytic iron. Here, we report the crystal structure at 2.4 angstrom resolution of human 5-LOX stabilized by replacement of this sequence. 相似文献
100.
The effects of Al3+ [supplied as Al2(SO4)3·18H2O] addition to culture media (pH 4.0) on growth, morphogenesis (in leaf explants), and oxidative stress reactions in in vitro cultures of ‘BA 29’ quince were investigated. Aluminium (Al 0.5 mM) strongly inhibited shoot growth in the proliferation and rooting phases (Al 2.2 mM), reduced shoot proliferation (Al 1.1 mM), and induced tissue browning. Superoxide dismutase (SOD) activity was increased in shoot cultures supplemented with 2 mM Al. Malondialdehyde (MDA) content of shoots was strongly increased by Al during proliferation (starting from Al 1.7 mM) and rooting (already at Al 1.1 mM), thus serving as a good ‘marker’ for Al toxicity. Even a low concentration of Al (0.5 mM) in the shoot induction medium was found to inhibit shoot regeneration. When standard (Al 0) shoot induction medium was used, leaf explant growth was only reduced by 2.2 mM Al in the subsequent growth phases. Following a preliminary selection for their growth on Al-enriched media, 82 potentially Al-tolerant quince somaclones were selected for further trials. 相似文献