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The objective of this study was to compare the effects of ground corn or liquid molasses fed as the sole supplemental nonstructural carbohydrate (NSC) source on production performance, milk fatty acid (FA) profile, grazing behavior, and N metabolism in grazing dairy cows. A strip-grazing management system was used, with cows offered a new strip of fresh herbage after each milking, resulting in approximately 16 h of access to pasture daily. Animals were fed a diet formulated to yield an 86:14 forage-to-concentrate ratio consisting [dry matter (DM) basis] of 74% mixed grass-legume herbage, 12% mixed-mostly legume baleage, 12% NSC source, and 2% mineral-vitamin premix. Twenty Jersey cows averaging (mean ± standard deviation) 121 ± 73 d in milk in the beginning of the study were randomly assigned to 1 of 2 herbage supplementation treatments: (1) baleage plus ground corn (B+GC) or (2) baleage + liquid molasses (B+LM). Both NSC sources were fed at a flat rate of 1.6 kg of DM/cow daily. The study lasted from June to September for a total of 15 wk with data and sample collection conducted in wk 3, 7, 12, and 15. Milk samples for FA analysis were collected in wk 2, 4, 6, 8, 9, 11, and 13. Data were analyzed using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC) for a randomized complete block design with repeated measures over time. Treatment × week interactions were observed for supplement DM intake, milk urea N, bite rate, urinary excretion of uric acid, and milk FA (e.g., 17:0, 18:0, cis-9,trans-11 18:2). Supplement DM intake was greatest in cows fed B+LM in wk 7, 12, and 15. Compared with cows fed B+GC, those fed B+LM had lower concentrations of milk urea N in wk 7 and 15. Milk yield, concentrations and yields of milk components, and plasma concentrations of essential AA, except Met, which was lowest with feeding B+LM, were not affected by supplementation. The plasma concentration of urea N was lowest with feeding B+LM. Cows fed B+GC spent more time grazing than those fed B+LM. Feeding B+GC increased cis-9 18:1 FA and most trans-18:1 FA in milk, whereas B+LM increased Σ odd-chain FA, Σ n-3 FA, and the trans-11 18:1 to trans-10 18:1 ratio, and decreased the n-6 to n-3 ratio. Based on current results, B+LM can entirely replace B+GC without negatively affecting milk yield or yields and concentrations of milk fat and true protein, while decreasing milk urea N, plasma urea N, and the milk trans-11 18:1 to trans-10 18:1 ratio, and increasing Σ n-3 FA.  相似文献   
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Recent and emerging technology permits psychologists today to recruit and test participants in more ways than ever before. But to what extent can behavioral scientists trust these varied methods to yield reasonably equivalent results? Here, we took a behavioral, face-to-face task and converted it to an online test. We compared the online responses of participants recruited via Amazon’s Mechanical Turk (MTurk) and via social media postings on Twitter, Facebook, and Reddit. We also recruited a standard sample of students on a college campus and tested them in person, not via computer interface. The demographics of the three samples differed, with MTurk participants being significantly more socio-economically and ethnically diverse, yet the test results across the three samples were almost indistinguishable. We conclude that for some behavioral tests, online recruitment and testing can be a valid—and sometimes even superior—partner to in-person data collection.  相似文献   
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Casler JG  Cook JR 《Ergonomics》2003,46(1-3):141-152
The purpose of the present research was to investigate the nature of potential manufacturing tasks humans may execute in a space environment. The success of space-based manufacturing (SBM) is suggested to be a precursor to permanent human presence in space. A working hypothesis for this study was that human work in the SBM environment would be substantially different from terrestrial manufacturing work. To investigate this hypothesis, a case analysis approach was developed that employed a function allocation and task analysis of a representative SBM process: the production of tailored industrial crystals. This research approach was chosen as the current state of engineering design for SBM is in the conceptual and early flow sheeting phases of a system life cycle. Results of the task analysis and function allocation process suggest response to corrective maintenance functions and to abnormal system conditions should be allocated to humans as opposed to automation. These results are discussed in relation to human factors engineering challenges associated with long-duration human presence in an SBM environment.  相似文献   
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Calculated product-moment correlations between Stanford-Binet Intelligence Scale IQs of 151 women and the Gesell Developmental Schedules Developmental Quotients of their illegitimate children (69 females and 82 males) on 5 occasions at 6-mo intervals. The correlations for Test 1, when the children were approximately 2 mo old and were residing in an institution, ranged from .14 to .30 and were statistically significant. Subsequent testing sessions, after the children had been adopted, yielded lower correlations at first, followed by increases in the final tests of the series. The generally modest correlations are interpreted in terms of homogeneity of the maternal sample, limitations of the Gesell scale, and early environmental input. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Children sometimes make scale errors, attempting to interact with tiny object replicas as though they were full size. Here, we demonstrate that instrumental tools provide special insight into the origins of scale errors and, moreover, into the broader nature of children's purpose-guided reasoning and behavior with objects. In Study 1, 1.5- to 3.5-year-olds made frequent scale errors with tools in a free-play session. Study 2 utilized a novel forced-choice method, representing a stronger test by handing 2-year-olds a feasible alternative for goal achievement, but children continued to make scale errors. Study 3 confirmed that errors were not based in perceptual immaturity. Results are explained using a framework of teleofunctional (purpose-based) reasoning as a powerful and early developing influence on children's actions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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