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81.
82.
Tropical corn silage was compared with sorghum silage as a basal forage in the diets of high producing dairy cows. Sorghum and tropical corn silages were each included in place of ground corn at incremental concentrations in the experimental diets. Eight separate diets were fed, four diets containing each silage ranging in forage neutral detergent fiber (NDF) from approximately 25 to 31% and ranging in total NDF from approximately 41 to 45%. Diets were arranged in a 2 x 4 factorial design and were fed to lactating cows (n = 24; pretrial mean milk production = 39 kg/d; body weight = 656 kg; and days in milk = 81). As concentrations of dietary NDF increased, intake and milk production decreased linearly. The impact of dietary NDF on intake was greater for diets based on tropical corn silage than for diets based on sorghum silage. Energy intake and milk production were reduced, but cows consumed more fiber when challenged with higher dietary concentrations of fiber. The in vitro rate and extent of digestion of dietary samples were correlated with intake response. The rate of in vitro fiber digestion was slower for samples that contained tropical corn silage than for samples that contained sorghum silage. In vivo digestibility measurements were influenced by intake and dietary composition. Results of this trial indicated that sorghum silage can have equal or slightly greater nutritional value than tropical corn silage when these forages are fed at equal concentrations of dietary fiber. 相似文献
83.
van Gelderen Amos; Schoonen Rob; de Glopper Kees; Hulstijn Jan; Simis Annegien; Snellings Patrick; Stevenson Marie 《Canadian Metallurgical Quarterly》2004,96(1):19
The authors report results of a study into the role of components of first-language (L1; Dutch) and second-language (L2; English) reading comprehension. Differences in the contributions of components of L1 and L2 reading comprehension are analyzed, in particular processing speed in L1 and L2. Findings indicate that regression weights of the L1 and L2 components are different. Although correlations between most processing speed components and reading comprehension are substantial, there are no unique contributions to the explanation of either L1 or L2 reading comprehension when linguistic and metacognitive knowledge are accounted for. In addition, L1 reading comprehension is shown to have a large contribution to L2 reading comprehension, supporting theories of L1-L2 transfer of reading skills. Results are discussed from a developmental perspective. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Two experiments tested the notion that people select actions that are diagnostic of favorable outcomes even though the actions do not cause those outcomes. In Exp I, 38 undergraduates immersed their forearm into a chest of circulating cold water before and after physical exercise. Depending on condition, Ss learned that a long life expectancy was associated with either increases or decreases in tolerance to cold water after the exercise. As predicted, Ss showed changes in tolerance on the 2nd trial in the direction correlated with a long, healthy life. In Exp II, 315 undergraduates encountered 1 of 2 theories about the sort of voters who determine the margin of victory in an election. Only one of the theories would enable voting Ss to imagine that they could induce other like-minded persons to vote. As predicted, more Ss indicated that they would vote given that theory than given a theory in which the S's vote would not be diagnostic of the electoral outcome, although the causal impact of the S's vote was the same under both theories. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Choices, values, and frames. 总被引:8,自引:0,他引:8
Discusses the cognitive and the psychophysical determinants of choice in risky and riskless contexts. The psychophysics of value induce risk aversion in the domain of gains and risk seeking in the domain of losses. The psychophysics of chance induce overweighting of sure things and of improbable events, relative to events of moderate probability. Decision problems can be described or framed in multiple ways that give rise to different preferences, contrary to the invariance criterion of rational choice. The process of mental accounting, in which people organize the outcomes of transactions, explains some anomalies of consumer behavior. In particular, the acceptability of an option can depend on whether a negative outcome is evaluated as a cost or as an uncompensated loss. The relationships between decision values and experience values and between hedonic experience and objective states are discussed. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
To assess the clinical usefulness of serum pro-gastrin-releasing peptide (Pro-GRP) as a tumor marker for small cell lung carcinoma (SCLC), we measured serum levels of Pro-GRP with a newly developed ELISA and measured serum levels of neuron-specific enolase (NSE) in 44 patients with untreated SCLC and 77 patients with untreated non-SCLC. We prospectively measured serum levels of Pro-GRP and NSE in SCLC patients after initial treatment until relapse. The sensitivity (70%) and specificity (91%) of Pro-GRP were similar to those of NSE (70 and 86%). Thirty-nine % of patients who had a partial response still had elevated serum levels of Pro-GRP at the time of restaging after initial treatment. In follow-up study, 94% of patients had elevated serum levels of Pro-GRP again at the time of relapse, whereas 37% of patients showed elevated levels of NSE. Levels of Pro-GRP increased a median of 35 (-95 to 151) days before clinical evidence of relapse was detected with successive physical examinations and imaging studies, whereas levels of NSE increased 20 (-85 to 124) days after relapse was detected (P < 0.05). Pro-GRP was helpful as a diagnostic aid and a marker for therapeutic effect and relapse in patients with SCLC, supplemented to serum NSE. 相似文献
87.
Effective properties of cemented granular materials 总被引:7,自引:0,他引:7
Jack Dvorkin Amos Nur Hezhu Yin 《Mechanics of materials : an international journal》1994,18(4):351-366
An analytical model is developed to describe the effective elastic properties of a cemented granular material that is modeled as a random packing of identical spheres. The elastic moduli of grains may differ from those of cement. The effective bulk and shear moduli of the packing are calculated from geometrical parameters (the average number of contacts per sphere and porosity), and from the normal and tangential stiffnesses of a two-grain combination. The latter are found by solving the problems of normal and tangential deformation of two elastic spherical grains cemented at their contact. A thin cement layer is approximated by an elastic foundation, and the grain-cement interaction problems are reduced to linear integral equations. The solution reveals a peculiar distribution pattern of normal and shear stresses at the cemented grain contacts: the stresses are maximum at the center of the contact region when the cement is soft relative to the grain, and are maximum at the periphery of the contact region when the cement is stiff. Stress distribution shape gradually varies between these two extremes as the cement's stiffness increases. The solution shows that it is mainly the amount of cement that influences the effective elastic properties of cemented granular materials. The radius of the cement layer affects the stiffness of a granular assembly much more strongly than the stiffness of the cement does. This theoretical model is supported by experimental results. 相似文献
88.
A mathematical model is developed to describe fluid flow and tracer dispersion in shallow tundishes. Two tundish designs are considered, namely one with a point inlet and a point outlet, and another with a point inlet and a slot outlet. Each of these designs is investigated, both in the absence and presence of flow control devices, the latter consisting of either conventional use of dams and weirs, or a magnetic field imposed perpendicularly to the main flow direction. 相似文献
89.
Greene Paul G.; Zeichner Amos; Roberts Nicolene L.; Callahan Edward J.; Granados Juan L. 《Canadian Metallurgical Quarterly》1989,57(4):484
We evaluated the effects of sensory information about cesarean delivery on prenatal maternal anxiety and on recovery subsequent to delivery by cesarean section. The 42 participants were recruited from a population of obstetric patients. Patients were assigned to either treatment or control groups and identified as sensitizers or repressors. Treatment groups viewed a slide/tape program presenting procedures involved in cesarean delivery. Control groups viewed a program presenting neutral information. Prepared patients classified as sensitizers showed less physiologic arousal during surgery and enhanced postsurgical recovery. Physiologic and self-report measures of anxiety indicated that the intervention itself was not a stressful event. The relations among arousal, subjective anxiety, coping styles, and treatment outcome are discussed and recommendations are made for further investigation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
33 women (aged 18–32 yrs) were randomly assigned to either a high-intensity exercise group, a low-intensity exercise group, or a waiting-list control group. All Ss recorded food intake during specified weeks before, during, and following the 7-wk exercise program. Results suggest that exercisers do not compensate for energy expenditure by increasing caloric intake and that choosing between low- and high-intensity exercise does not differentially alter caloric intake. Nevertheless, maximization of negative energy balance or weight loss may be best achieved by exercise programs of high frequency and intensity. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献