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21.
In a Prisoner's Dilemma type game, Ss (male and female students) were asked to make repeated choice between 2 alternatives, R and B, where R is presumably the cooperative and B the competitive choice. While believing that they were playing persons of the same sex, Ss actually played a simulated partner who, for ? of the group, chose 83% random R and, for the other ?, 83% random B for 30 trials. Thereafter for 60 trials, the simulated partner chose according to a strategy of 83% matching, 17% mismatching the choices of S. The purpose of this procedure was to determine the effects of initial level of simulated cooperation on S's own level of cooperation. The results failed to demonstrate that the level of simulated cooperation employed functioned to determine choice by S. Ss had been stratified according to a test of character which failed to predict choice. However, a 2nd scoring formula employed on this test did significantly distinguish the amount of R choice emitted by S and deserves further examination. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
The ability of rats to select a warm environment was studied as a function of postnatal age (birth to 13 days), using 100 Long-Evans hooded rats as Ss. Ss younger than 5 days demonstrated no choice response (movement to a warm compartment, 36-37 .C); however, they did demonstrate movement within the start compartment (23 .C). Increasing the motor capabilities of the pups, by injection of levodopa (50 mg/kg), elicited a choice response in 4-5 day-old Ss. Younger Ss demonstrated no choice of a warm environment even though they moved considerably. Also there was no difference between levodopa-treated and control Ss in the magnitude of temperature change in pups isolated from their mother for 1 hr. The evidence suggests development of behavioral thermoregulatory mechanisms prior to abilities for internal regulation. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
Disorders of iron metabolism affect over a billion people worldwide. The circulating peptide hormone hepcidin, the central regulator of iron distribution in mammals, holds great diagnostic potential for an array of iron-associated disorders, including iron loading (β-thalassemia), iron overload (hereditary hemochromatosis), and iron deficiency diseases. We describe a novel high-throughput matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry assay for quantification of hepcidin in human plasma. This assay involves enrichment using a functionalized MALDI chip, a novel solvent-detergent precipitation buffer, and quantification using a stable isotope labeled internal standard. The linear range of hepcidin in plasma was 1-120 nM, with a low limit of quantification (LOQ) (1 nM), high accuracy (<15% relative error (RE)), and high precision (intraday average 5.52-18.48% coefficient of variation (CV) and interday 9.32-14.83% CV). The assay showed strong correlation with an established hepcidin immunoassay (Spearman; R(2) = 0.839 n = 93 ethylenediaminetetraacetic acid (EDTA) plasma). A collection of normal healthy pediatric samples (range 3.8-32.5 ng/mL; mean 12.9 ng/mL; n = 119) showed significant differences from an adult collection (range 1.8-48.7 ng/mL; mean 16.1 ng/mL; n = 95; P = 0.0096). We discuss these preliminary reference ranges and correlations with additional parameters in light of the utility and limitations of hepcidin measurements as a stand-alone diagnostic and as a tool for therapeutic intervention.  相似文献   
24.
A review of 1,000 consecutive coronary angiograms, most of them performed for evaluation of angina pectoris, yielded 9 examples of congenital anomalies of the coronary arteries. In 2 cases the angina may have been due to malposition of the left coronary artery or one of its branches. There were 2 cases of aberrant origin of the circumflex artery from the right coronary artery, 2 cases of aberrant left anterior descending artery, 3 cases in which all three major coronary branches arose from the right aortic sinus, and 2 cases of coronary artery fistulas. Malposition of the coronary artery should be considered as a possible cause of angina.  相似文献   
25.
Pyrolytic carbon was used as fuel in a solid oxide fuel cell (SOFC) with a yttria-stabilized zirconia (YSZ) electrolyte and a bi-layer anode composed of nickel oxide gadolinia-doped ceria (NiO-GDC) and NiO-YSZ. The common problems of bulk shrinkage and emergent porosity in the YSZ layer adjacent to the GDC/YSZ interface were avoided by using an interlayer of porous NiO-YSZ as a buffer anode layer between the electrolyte and the NiO-GDC primary anode. Cells were fabricated from commercially available component powders so that unconventional production methods suggested in the literature were avoided, that is, the necessity of glycine-nitrate combustion synthesis, specialty multicomponent oxide powders, sputtering, or chemical vapor deposition. The easily-fabricated cell was successfully utilized with hydrogen and propane fuels as well as carbon deposited on the anode during the cyclic operation with the propane. A cell of similar construction could be used in the exhaust stream of a diesel engine to capture and utilize soot for secondary power generation and decreased particulate pollution without the need for filter regeneration.  相似文献   
26.
The soil saprophytic fungus Myrothecium verrucaria was cultivated from glucose, starch, or xylan as the carbon source, and the biomass was compared with three selected feedstuffs. Fungal biomass was analyzed for nitrogen, protein, lipid, water soluble fraction, hemicellulose, cellulose, lignin, and residual ash, and the in vitro dry matter disappearance was determined. The chemical composition of M. verrucaria varied with substrate. In nitrogen content, the fungal biomass was more similar to alfalfa hay than to milo stalks or wheat straw. Content of water soluble fraction of fungal biomass was between those of alfalfa hay and milo stalks; content of hemicellulose was between those of milo stalks and wheat straw. The fungal fractions identified as cellulose and lignin varied widely with substrate. The fungal biomass was less digestible than alfalfa hay but more digestible than milo stalks or wheat straw. There may be potential uses of this organism in upgrading nutritive value of low-quality forages.  相似文献   
27.
False memories were investigated for aurally and visually presented lists of semantically associated words. In Experiment 1, false written recall of critical intrusions was reliably lower following visual presentation compared with aural presentation. This presentation modality effect was attributed to the use of orthographic features during written recall to edit critical intrusions from visually presented lists. As predicted by this hypothesis, the modality effect was eliminated when the mode of recall was spoken rather than written. In Experiment 2, the modality effect in written recall was again replicated and then eliminated with an orienting task that ensured orthographic encoding even of aurally presented words. Thus, the modality effect appears to depend on using orthographic information to distinguish true from false verbal memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
The physical form of an urban settlement is a product of the reciprocal relationship between the humans and the ecological systems in the area which act together to create an urban landscape that changes through time. While many of the interactions between the natural world and the built environment occur at the regional level, the quality of life experienced by residents is in large part a function of environmental conditions in the neighborhood. This article explores the benefits to neighborhood planning from incorporating urban environmental history. It reviews the conceptual territory of urban environmental history and presents a framework for its application to neighborhood planning. An environmental history completed for a neighborhood is highlighted to illustrate the technique.  相似文献   
29.
This study examines the temperamental characteristics of children who were identified at age two as being slow in expressive language development, and those of peers with normal language history. When the children were in first grade (approximately age six), parents and clinicians rated subjects' temperamental characteristics, using a standardized temperament assessment instrument. Subjects with a history of slow expressive language development were rated significantly lower on Approach/Withdrawal--indicating shyness, aloofness, or reduced outgoingness--than peers with normal language history. Approach/Withdrawal scores were significantly correlated with average sentence length in spontaneous speech, and this measure also predicted Approach/Withdrawal scores in regression analyses. The clinical and theoretical implications of these findings for early language delay are discussed.  相似文献   
30.
The equilibrium partial pressure of sulfur vapor over Ni?S melts has been determined by equilibrating the melts with H2-H2S gas mixtures at temperatures from 1100°C through 1600°C and for melt compositions ranging from nickel saturation up to about 27 wt pct sulfur. An optical interferometer was employed to monitor the system’s approach to equilibrium and to analyze the composition of the equilibrium gas phase. A mathematical model was employed to correlate these data with those of Nagamori and Ingraham2 for temperatures from 800°C through 1100°C. The model was somewhat complicated but it described the Ni?S melts very well over unusually wide ranges of composition and temperature;e. g. σ (logP S2 1/2 )=0.029.  相似文献   
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