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排序方式: 共有308条查询结果,搜索用时 296 毫秒
61.
This study examined the contributions of physical and sensorimotor development to manipulation in capuchins (Cebus apella) from birth to 2 years. Between months 1–6 and 7–12, manipulation increased significantly in frequency, in the proportion that was vigorous or required fine motor control, and in the proportion directed at portable objects. Fine motor control, moving objects in relation to the body, and stamina are largely in place by 12 months, after which little changed. All elements of the manipulative repertoire have appeared, and vigorous and dexterous activities have peaked before fully independent foraging. Emergence of permanent dentition and achievement of approximately half of adult body size accompany the attainment of fully independent foraging at 15 months. Thereafter, increasing strength and specific knowledge probably contribute more to changing foraging competence in young capuchins than do stamina and sensorimotor development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Rmi Loire Herv Pigay Jean‐Ren Malavoi Leah Beche Quentin Dumoutier Julie Mosseri Caroline Kerjean 《河流研究与利用》2019,35(8):1107-1118
Large‐scale flow release experiments are becoming common for improving aquatic habitat quality downstream of dams. Because of the naturally high fine sediment load in the Durance River, France due to inputs from torrential tributaries draining badlands, unpredictable high flow events with dam overspill are not always sufficient to prevent clogging, which can lead to habitat degradation (especially spawning habitats) in bypassed reaches. Therefore, large‐scale flow experiments were conducted on four reaches to test the efficacy of clear‐water releases to improve aquatic habitat conditions. Continuous measurements of water depth, suspended sediment concentrations, and turbidity were conducted during twelve releases and compared on nine. Before and after each release, superficial clogging was measured. The study shows that there is a link between the volume of suspended sediments carried by water releases and the initial clogging. The volumes carried were low compared with the river's annual transport. The effect on clogging can vary significantly from one release to another. In particular, the hydrological context surrounding the releases has a significant influence on clogging. Comparisons of monitoring showed that releases are more effective on reaches that are more severely regulated (high hydrological control) than on those that are less well‐controlled. The areas with the highest initial clogging tend to unclog more than those with lower initial clogging; however, the latter zones are most impacted by ineffective releases. Performing a release on environments with low initial clogging can therefore be environmentally damaging. To ensure that releases are successful and that intervention is warranted, initial clogging should be measured in the field and releases should only be performed if the clogging is judged to be unfavourable. 相似文献
63.
Ensuring that service-oriented systems can adapt quickly and effectively to changes in service quality, business needs and their runtime environment is an increasingly important research problem. However, while considerable research has focused on developing runtime adaptation frameworks for service-oriented systems, there has been little work on assessing how effective the adaptations are. Effective adaptation ensures the system remains relevant in a changing environment and is an accurate reflection of user expectations. One way to address the problem is through validation. Validation allows us to assess how well a recommended adaptation addresses the concerns for which the system is reconfigured and provides us with insights into the nature of problems for which different adaptations are suited. However, the dynamic nature of runtime adaptation and the changeable contexts in which service-oriented systems operate make it difficult to specify appropriate validation mechanisms in advance. This paper describes a novel consumer-centered approach that uses machine learning to continuously validate and refine runtime adaptation in service-oriented systems, through model-based clustering and deep learning. 相似文献
64.
We revisit the classic problem of preemptive scheduling on m uniformly related machines. In this problem, jobs can be arbitrarily split into parts, under the constraint that every job is processed completely, and that the parts of a job are not assigned to run in parallel on different machines. We study a new objective which is motivated by fairness, where the goal is to minimize the sum of the two maximal job completion times. We design a polynomial time algorithm for computing an optimal solution. The algorithm can act on any set of machine speeds and any set of input jobs. The algorithm has several cases, many of which are very different from algorithms for makespan minimization (algorithms that minimize the maximum completion time of any job), and from algorithms that minimize the total completion time of all jobs. 相似文献
65.
Leah Castillon Berardi Vernon L. Frampton 《Journal of the American Oil Chemists' Society》1957,34(8):399-401
- The crude oils studied contained from 0.00 to 0.04% gossypol.
- Much of the gossypol added to crude cottonseed oils disappeared in one hour.
- The disappearance of gossypol from refined, bleached, and deodorized cottonseed oil, from highly purified tripelargonin, and from ethyl acetate is demonstrable after the lapse of one hour.
- It is suggested that the initial reaction of gossypol in the oils is an ester exchange reaction.
- It is further suggested that secondary reactions result in the production of a red coloration product that is not removable from the oil by the standard refining and bleaching methods.
66.
Walter A. Pons Jr. Mildred D. Murray Marion F. H. LeBlanc Jr. Leah E. Castillon 《Journal of the American Oil Chemists' Society》1953,30(3):128-132
Summary The processing of cottonseed by five commercial mills has been systematically examined with reference to free gossypol reduction,
nitrogen solubility, thiamine reduction, material balances of total gossypol, and the distribution of gossypol in processing.
One hydraulic mill reduced the free gossypol in the meal to a low level, approximating the level obtained in screw pressing.
For a given mill the free gossypol contents of the meals were found to be fairly uniform.
Low free gossypol content of hydraulic-pressed meals depends on the thoroughness with which the gossypol is bound in the cooking.
Gossypol is bound in both the cooking and pressing in the production of screw-pressed meals.
A relatively small amount of total gossypol is lost or destroyed in processing cottonseed by either hydraulic- or screw-pressing
methods. This small loss occurs while the meats are being prepared for pressing. No significant loss was found which could
be attributed to the pressing operations.
Serew-pressed oils appear to contain several times as much gossypol as hydraulic-pressed oils, with the amount dependent on
the extent of the binding of gossypol in the cooking and mechanical preparation of the meats for pressing.
The high temperatures developed in screw pressing contributed to a higher reduction in thiamine and nitrogen solubility than
was observed for hydraulic pressing.
One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S.
Department of Agriculture. 相似文献
67.
Jacobs K Foley G Punnett L Hall V Gore R Brownson E Ansong E Markowitz J McKinnon M Steinberg S Ing A Wuest E Dibiccari L 《Ergonomics》2011,54(2):206-219
The objective of this pilot study was to identify if notebook accessories (ergonomic chair, desktop monitor and notebook riser) combined with a wireless keyboard, mouse and participatory ergonomics training would have the greatest impact on reducing self-reported upper extremity musculoskeletal discomfort in university students. In addition to pre-post computing and health surveys, the Ecological Momentary Assessment was used to capture change in discomfort over time using a personal digital assistant (PDA) as the e-diary. The PDA was programmed with a survey containing 45 questions. Four groups of university students were randomised to either intervention (three external computer accessories) or to control. Participants reported less discomfort with the ergonomic chair and notebook riser based on the pre-post survey data and the e-diary/PDA ANOVA analysis. However, the PDA data, adjusted for the effect of hours per day of computer use, showed no benefit of the chair and limited benefit from the riser. Statement of Relevance:University students' use of notebook computers has increased. This study found evidence of a positive effect of an adjustable chair or notebook riser when combined with ergonomic training on reducing discomfort. Daily notebook computer use of 4?h was confirmed as a risk factor. Without some form of ergonomic intervention, these students are likely to enter the workforce with poor computing habits, which places them on the road to future injuries as technology continues to play a dominant role in their lives. 相似文献
68.
Craig D. Zamuda Thomas Wall Leah Guzowski Joshua Bergerson Janet Ford Lawrence Paul Lewis Robert Jeffers Sean DeRosa 《The Electricity Journal》2019,32(9):106642
This paper describes management practices of a model resilient electric utility that can serve as a framework for advancing planning and preparation for extreme weather and climate hazards. The framework focuses on practices grouped into eight domains progressing through five levels of maturity. For each domain, a discussion of resilience management practices is provided along with examples. By assessing its maturity level and taking steps to increase it, a utility can realize increased resilience benefits. 相似文献
69.
Quality characteristics of angel food cake and muffin using lentil protein as egg/milk replacer
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Marcela Jarpa‐Parra Leah Wong Wendy Wismer Feral Temelli Jay Han Weijuan Huang Ewelina Eckhart Zhigang Tian Kaiyong Shi Tianwei Sun L. Chen 《International Journal of Food Science & Technology》2017,52(7):1604-1613
Replacement of animal proteins could be interesting for the food industry because it allows long‐term cost savings, among other reasons. Replacing egg/milk protein (50–100 wt%) by lentil protein (LP) was evaluated on angel cake/muffin quality. The replacement did not significantly affect final product volume, neither the muffins nor the angel food cakes. LP did not affect dough formation and contributed to hold crumb structure building an entangled network in both cake products. In addition, angel cakes and muffins containing LP had significantly lower baking loss than the control. Inferior quality for angel cakes and muffins containing LP was observed regarding hardness and chewiness that increased upon storage, compared to the control. For sensory evaluation in angel cakes, appearance of LP formulations showed lower scores than the control, likely due to the change of crumb colour. Other attributes were not significantly impacted by LP presence. For muffins, M‐100‐LPC formulation showed significant differences with the control for most of the attributes, except appearance and flavour. Indeed, consumers preferred muffins with 100% egg/milk protein replacement, which received higher acceptability scores than control. They also appreciated the ‘nutty’ flavour and moisture of angel cake with 50% egg protein replacement. This research suggests that lentil protein can totally or partially substitute egg/milk protein as foam and emulsion stabiliser in cakes, producing products with satisfactory quality. 相似文献
70.
John S. Maninang Leah Raquel C. Lopido-SeseMa. Concepcion C. Lizada Hiroshi Gemma 《Food chemistry》2012,131(2):705-712
The adverse reaction to 1.25 g/kg ethanol was monitored in male Fischer rats given durian or cabbage (2.4 g FW/100 g BW/day), administered intragastrically. During the first ethanol challenge, a reduced rate of blood acetaldehyde clearance and hypothermia, which is associated with the disulfiram-ethanol reaction, was observed in rats given durian or cabbage. Blood ethanol levels and rate of acetaldehyde elimination were lowest 30 min after the first ethanol challenge in rats given cabbage, while a similar but more exacerbated trend was observed at 60 min in rats given durian. When subjected to conditioned taste aversion using saccharine solution (0.2% v/v) paired with ethanol administration, the rats given durian or cabbage exhibited aversion, with the former showing the earliest and most pronounced response, persisting through to the last ethanol challenge. Rats given cabbage exhibited delayed aversion, which progressively increased to the same level as that observed in rats given durian. 相似文献