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81.
82.
Lee LP  Szema R 《Science (New York, N.Y.)》2005,310(5751):1148-1150
Observing systems in nature has inspired humans to create technological tools that allow us to better understand and imitate biology. Biomimetics, in particular, owes much of its current development to advances in materials science and creative optical system designs. New investigational tools, such as those for microscopic imaging and chemical analyses, have added to our understanding of biological optics. Biologically inspired optical science has become the emerging topic among researchers and scientists. This is in part due to the availability of polymers with customizable optical properties and the ability to rapidly fabricate complex designs using soft lithography and three-dimensional microscale processing techniques.  相似文献   
83.
Prefoldins (PFDs) are members of a recently identified, small-molecular weight protein family able to assemble into molecular chaperone complexes. Here we describe an unusually large member of this family, termed URI, that forms complexes with other small-molecular weight PFDs and with RPB5, a shared subunit of all three RNA polymerases. Functional analysis of the yeast and human orthologs of URI revealed that both are targets of nutrient signaling and participate in gene expression controlled by the TOR kinase. Thus, URI is a component of a signaling pathway that coordinates nutrient availability with gene expression.  相似文献   
84.
To extend the analytical capabilities of the pyrolysis-gas chromatograph-mass spectrometry system that has been successfully utilized in the past as an integrated reaction, separation, and identification system to study label incorporation patterns in Maillard reaction products, a novel methodology was developed to analyze the composition of nonvolatile residues of the initial reaction products. This was achieved through a postpyrolytic in-situ derivatization technique using trimethylsilyldiethylamine. Application of this technique to the investigation of the nonvolatile products formed during pyrolysis of glucose alone and in the presence of glycine has indicated the formation of several redox-active hydroxylated benzene derivatives such as 1,2,3-trihydroxybenzene (pyrogallol), 1,4-dihydroxybenzene (hydroquinone), 1,2-dihydroxybenzene (catechol), and 2,5-dihydroxypyrazine. Labeling studies have indicated that the intact glucose carbon backbone was involved in the construction of the benzene ring of the hydroxylated benzene derivatives and that dimerization of glycine alone can lead to the formation of 2,5-dihydroxypyrazine.  相似文献   
85.
Sleep  Bethany  Mason  Sean  Janik  Les  Mosley  Luke 《Precision Agriculture》2022,23(1):194-218
Precision Agriculture - Soil acidification is a major and growing concern in many cropping regions globally. Whilst spatial variability in acidification is a common consideration in the management...  相似文献   
86.
Species responses to climate change are often measured at broad spatiotemporal scales, which can miss the fine-scale changes that are most relevant to conservation and fisheries management. We develop a scaleable geostatistical approach to assess how juvenile and adult fish distributions have been shaped by changes in bottom temperature and dissolved oxygen over a recent decade of warming in the northeast Pacific. Across 38 demersal fishes, biomass trends were associated negatively with warming and positively with dissolved oxygen, but when trends in both biomass and climate were converted to velocities—the speed and direction a population would have to move to maintain consistent conditions—the effect of temperature change differed depending on local conditions. In the warmest locations, warming velocities were associated with negative biotic velocities for 19 of 69 species-maturity combinations, and yet were almost always associated with stable or positive biotic velocities in the coolest locations (64 of 69). These spatially consistent biomass declines (negative biotic velocities) in the warmest locations and increases in cooler locations suggest a redistribution of species with the potential for new ecological and fisheries interactions. After controlling for temperature, the more spatially consistent effects of dissolved oxygen were often negative, suggesting a mechanism other than hypoxia avoidance—potentially changes in primary production. Our approach identifies the species and locations that are most sensitive to observed changes in the environment at any scale, thus facilitating future vulnerability assessments.  相似文献   
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Hazard Analysis and Critical Control Points (HACCP) systems are a risk based preventive approach developed to increase levels of food safety assurance. This is part 1 of a pilot study on the development, implementation and evaluation of a HACCP-based approach for the control of good udder health in dairy cows. The paper describes the use of a novel approach based on a deconstruction of the infectious process in mastitis to identify Critical Control Points (CCPs) and develop a HACCP-based system to prevent and control mastitis in dairy herds. The approach involved the creation of an Infectious Process Flow Diagram, which was then cross-referenced to two production process flow diagrams of the milking process and cow management cycle. The HACCP plan developed, may be suitable for customisation and implementation on dairy farms. This is a logical, systematic approach to the development of a mastitis control programme that could be used as a template for the development of control programmes for other infectious diseases in the dairy herd.  相似文献   
89.
There is little information in veterinary literature regarding the diagnostic accuracy of aspirate cytology for the diagnosis of canine osteosarcoma (OSA). The authors compared the diagnostic accuracy of a novel method of cytologic collection, termed core aspirate cytology (CA), with fine needle aspiration (FNA) and histopathology in 27 dogs with lytic and/or proliferative bone lesions. Alkaline phosphatase (ALP) staining was performed to confirm the diagnosis of OSA cytologically. OSA was accurately diagnosed in 85% and 95% of FNA and CA, respectively. ALP staining was 100% sensitive for the diagnosis of OSA. CA using a bone marrow biopsy needle allowed for penetration of cortical bone and aspirate cytology with a larger bore needle than FNA; however, there was no significant difference in diagnostic accuracy between techniques. Aspirate cytology with ALP staining was a safe, accurate, and minimally invasive diagnostic test for the evaluation of suspected OSA lesions in dogs.  相似文献   
90.
Movement analysis techniques allow objective and quantitative assessment of kinematic gait analysis. Consistent repeatability of the kinematic data is essential for such assessments. This study investigated whether the repeatability of a standardized Equinalysis Elite gait analysis system is sufficient to allow its use in clinical evaluation of equine lameness with reliable documentation of individual locomotion patterns. The extent to which examinations on different days affected the results when a standardized protocol was used was investigated. The repeatability of distal limb kinematics in nine sound horses over three successive days at one location was investigated. Measurements were performed at the examination area, for three motion cycles at the walk and trot, in each direction per day. Skin markers were placed on the lateral aspect of the coffin joint, forelimb fetlock joint, hindlimb fetlock joint, carpus, tarsus, elbow, and stifle, at clipped sites marked with a permanent marker. The inter-day repeatability of angular measurements of the carpus, tarsus, forelimb fetlock, and hindlimb fetlock joints was determined. A low degree of inter-day repeatability was found with statistically significant (P ≤ .05) differences between findings on different days, observed in the time-angle diagrams of left and right carpus, tarsus, forelimb fetlock, and hindlimb fetlock joints of all horses, at both walk and trot. The standardized Equinalysis Elite system for gait analysis of distal limb kinematics in the horse did not provide highly repeatable data in this setting.  相似文献   
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