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排序方式: 共有3334条查询结果,搜索用时 19 毫秒
991.
Peter T. Cummings Clare McCabe Christopher R. Iacovella Akos Ledeczi Eric Jankowski Arthi Jayaraman Jeremy C. Palmer Edward J. Maginn Sharon C. Glotzer Joshua A. Anderson J. Ilja Siepmann Jeffrey Potoff Ray A. Matsumoto Justin B. Gilmer Ryan S. DeFever Ramanish Singh Brad Crawford 《American Institute of Chemical Engineers》2021,67(3):e17206
992.
Eugenio Revilla Jorge F. López José-María Ryan 《European Food Research and Technology》2005,220(5-6):592-596
The anthocyanin fingerprint of Tempranillo wines made with grapes from two different vineyards of Rioja Alta has been studied by high-performance liquid chroatography during their ageing in oak barrels and their storage in stainless-steel tanks. The data were submitted to multifactorial analysis of variance, taking into account several factors: vineyard, age of wines, type of wine (free run wine and a coupage of free run wine and press wine), and type of container (oak barrels or stainless-steel tanks). The results indicate that both the length of ageing or storage and the vineyard where the grapes were grown affect the anthocyanin fingerprint of wines. The effect of the other two factors (type of wine and type of container) on the anthocyanin fingerprint of wines was quite low, despite the differences observed in several spectrophotometric parameters related to colour and phenolics. 相似文献
993.
Use of membrane inlet mass spectrometers (MIMS) for quantitative measurements of dissolved gases and volatile organics over a wide range of ocean depths requires characterization of the influence of hydrostatic pressure on the permeability of MIMS inlet systems. To simulate measurement conditions in the field, a laboratory apparatus was constructed for control of sample flow rate, temperature, pressure, and the concentrations of a variety of dissolved gases and volatile organic compounds. MIMS data generated with this apparatus demonstrated thatthe permeability of polydimethylsiloxane (PDMS) membranes is strongly dependent on hydrostatic pressure. For the range of pressures encountered between the surface and 2000 m ocean depths, the pressure dependent behavior of PDMS membranes could not be satisfactorily described using previously published theoretical models of membrane behavior. The observed influence of hydrostatic pressure on signal intensity could, nonetheless, be quantitatively modeled using a relatively simple semiempirical relationship between permeability and hydrostatic pressure. The semiempirical MIMS calibration developed in this study was applied to in situ underwater mass spectrometer (UMS) data to generate high-resolution, vertical profiles of dissolved gases in the Gulf of Mexico. These measurements constitute the first quantitative observations of dissolved gas profiles in the oceans obtained by in situ membrane inlet mass spectrometry. Alternative techniques used to produce dissolved gas profiles were in good accord with UMS measurements. 相似文献
994.
Marine oil-based finishing diets have been used to restore fillet FA profile in several “medium-fat” fleshed aquaculture species,
and a simple dilution model describing FA turnover has been established to predict and tailor final fillet composition. We
evaluated finishing diet efficacy and suitability of the dilution model to describe patterns of FA change in a lean-fleshed
model, sunshine bass. Two practical diet (45% crude protein, 15% crude lipid) were formulated, respectively containing corn
oil (CO) or menhaden oil (MO) as the primary lipid sources. Sunshine bass (age 1 [⊃ 14 mo], 347 ±8.6 g, mean individual weight
±SEM) were stocked in a recirculating system and fed the diets according to different feeding regimens during the final 28
wk of the production cycle. Control groups were fed the CO or the MO feeds exclusively; whereas, the remaining treatment groups
were transitioned from the CO diet to the MO diet at 4−, 8−, or 12-wk intervals. Upon completion of the feeding trial, fish
were harvested, and production performance and fillet composition were assessed. Replacing MO with CO as the primary lipid
source in sunshine bass diets yielded fillets with distinctly different FA profiles; however, finishing with a MO-based diet
offered significant compensation for CO-associated reductions in fillet long-chain highly unsaturated FA (LC-HUFA). Although
complete restoration was not observed, we achieved significant augmentation of endogenous n−3 FA within 4 wk of feeding the
MO diet, and observed a significant increase in LC-HUFA and a beneficial shift in n−3∶n−6 FA ratio after 8 weeks. Simple dilution
accurately predicted tissue composition for most FA; however, deviations from the model were noted, suggesting selective retention
of n−3, PUFA, and LC-HUFA and preferential catabolism of saturates. We conclude marine oil-based finishing diets can rapidly
augment beneficial FA levels in sunshine bass fillets; however, simple dilution models do not fully describe selective FA
metabolism observed for this lean-fleshed fish.
Presented at Aquaculture America 2006, February 13–16, 2006 Las Vegas, nevada and Aqua 2006, May 9–13, 2006 Florence, Italy 相似文献
995.
David W. Macdonald Ryan S. Squires Shaela A. Avery Jason Adams Melissa Baker Christopher R. Cunningham Nicholas B. Heimann David L. Kooyman Robert E. Seegmiller 《International journal of molecular sciences》2013,14(8):16515-16531
Heterozgyous spondyloepiphyseal dysplasia congenita (sedc/+) mice expressing a missense mutation in col2a1 exhibit a normal skeletal morphology but early-onset osteoarthritis (OA). We have recently examined knee articular cartilage obtained from homozygous (sedc/sedc) mice, which express a Stickler-like phenotype including dwarfism. We examined sedc/sedc mice at various levels to better understand the mechanistic process resulting in OA. Mutant sedc/sedc, and control (+/+) cartilages were compared at two, six and nine months of age. Tissues were fixed, decalcified, processed to paraffin sections, and stained with hematoxylin/eosin and safranin O/fast green. Samples were analyzed under the light microscope and the modified Mankin and OARSI scoring system was used to quantify the OA-like changes. Knees were stained with 1C10 antibody to detect the presence and distribution of type II collagen. Electron microscopy was used to study chondrocyte morphology and collagen fibril diameter. Compared with controls, mutant articular cartilage displayed decreased fibril diameter concomitant with increases in size of the pericellular space, Mankin and OARSI scores, cartilage thickness, chondrocyte clustering, proteoglycan staining and horizontal fissuring. In conclusion, homozygous sedc mice are subject to early-onset knee OA. We conclude that collagen in the mutant’s articular cartilage (both heterozygote and homozygote) fails to provide the normal meshwork required for matrix integrity and overall cartilage stability. 相似文献
996.
The wear of tool blades for cost-effective scrap tire shredding is investigated. Rotary disk cutters are widely used for cutting scrap tires into small pieces. The hard, wear-resistant tool blades mounted on the periphery of disk cutters maintain a narrow gap between blades and generate the cutting action. The kinematics of the relative motion of two adjacent disk cutters is derived to model the overlap region on blades during cutting. The model predictions match well with the actual shapes of the worn regions on used tool blades. The wear of tool blades made of AISI D2 and CRU-WEAR (CW) tool steels for scrap tire shredding is evaluated. A coordinate measurement machine was used to measure the tool wear. The wear on the blade surface is not uniform. Regions with high wear rate are explained using the kinematics analysis. The CW blades show a lower wear rate, about half of that of D2 blades, and a potential choice for cost savings. 相似文献
997.
998.
This study examines issues of online identity and language use among male and female teenagers who created and maintained weblogs, personal journals made publicly accessible on the World Wide Web. Online identity and language use were examined in terms of the disclosure of personal information, sexual identity, emotive features, and semantic themes. Male and female teenagers presented themselves similarly in their blogs, often revealing personal information such as their real names, ages, and locations. Males more so than females used emoticons, employed an active and resolute style of language, and were more likely to present themselves as gay. The results suggest that teenagers stay closer to reality in their online expressions of self than has previously been suggested, and that these explorations involve issues, such as learning about their sexuality, that commonly occur during the adolescent years. 相似文献
999.
Danielle Hutchings Robert Simpson Ryan Stauffer Douglas Wahl 《Canadian Metallurgical Quarterly》2007,13(1):1-8
The Golden Gate Bridge is an iconic landmark, which has long held the distinction of being the most popular structure in the world to commit suicide. A general process is presented for policy makers’ use to generate conversation and clarify their values in making decisions about public works improvements. This applies particularly well where issues of aesthetics and cost are emotionally and politically charged. The Golden Gate Bridge serves as a case study of how this process can be used. Three design solutions were generated on the basis of architectural concerns and developed in the context of evaluation criteria. A value-based decision analysis approach was taken to determine the preference structure of decision makers involved and to provide a rational framework for further development. Results indicate that existing preferences among decision makers may not be consistent with their public decisions and could be clarified given a more rigorous framework. The do-nothing option is likely to be less preferred to other options given a thorough definition of the acceptance criteria. 相似文献
1000.
Neuroanatomical and pharmacological experiments support the existence of a homologue of the mammalian substantia nigra-basal ganglia circuit in the amphibian brain. Demarcation of borders between the striatum and pallidum in frogs, however, has been contentious, and direct evidence of functional coupling between the putative nigral and striatal homologues is lacking. To clarify basal ganglia function in anurans, the authors used expression of immediate-early gene egr-1 as a marker of neural activation in the basal ganglia of túngara frogs (Physalaemus pustulosus). Regional variation in egr-1 mRNA levels distinguished striatal and pallidal portions of the basal ganglia and supported the grouping of the striatopallidal transition zone with the dorsal pallidum. As further evidence for a functional coupling between the dopaminergic cells in the posterior tuberculum (the putative substantia nigra homologue) and the basal ganglia, a positive relationship was demonstrated between the size of the dopaminergic cell population and the neural activation levels within the dorsal pallidum. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献