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11.
Editorial     
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12.
In a series of 10-day pair feeding experiments it was found that the nutritional value of diets containing beans was essentially the same for rats aged between 30 and 123 days. Thus net protein utilisation (NPU) values of 25–39 on diets containing Processor bean (35 g protein kg?1) + egg albumin (65g protein kg?1) were obtained. As food intakes were considerably reduced when rats were fed diets containing more than 35g protein kg?1 of Processor bean, the measurement of protein utilisation became increasingly more difficult. The severe disruption of the brush borders of duodenal and jejunal enterocytes, originally observed when bean-containing diets were fed to young (30-day-old) rats was also found with rats up to the age of 120 days on similar diets. Similarly, the development of circulating anti-lectin antibodies in the animals showed no age dependence within the age limits investigated. It was also shown that oral immunisation did not protect the rats from the effects of toxicity and that the immune response was a result of continuous absorption of lectin throughout the feeding period. Thus the extent and the mechanism of toxicity of Phaseolus vulgaris bean lectins were found not to be dependent on the age or maturity of the animal.  相似文献   
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Inductive social skills training (ISST), skill assembly social skills training (SASST), and cognitive relaxation coping skills (CRCS) training were compared with a no-treatment control condition for general anger reduction. At 4-wk follow-up, compared with the control group, all treatment groups showed equivalent reductions of the amount of anger experienced in a wide range of situations. ISST and CRCS Ss reported less anger in their worst ongoing provocation than did control Ss, whereas SASST Ss did not differ from Ss of other groups. Treatment groups enhanced anger control equally relative to the control group, but only the CRCS group significantly lowered outward, negative expression of anger, and only the ISST group reduced anger suppression, although active treatment groups did not differ from one another on these measures. The ISST group lowered day-to-day anger more than other groups. No treatment effects were found for nontargeted trait anxiety and assertiveness. Results are discussed in terms of prior findings and the efficacy and flexibility of ISST. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
15.
Rotaviruses are the leading cause and coronaviruses are the major contributors of acute gastroenteritis in the young of various mammalian and avian species. Despite numerous trials and decades of research, vaccines have limited efficacy particularly for calves. As an alternative method of controlling infection, we have investigated broad spectrum antiviral agents that are not discriminatory among various viruses. This report involves testing a variety of adsorbent agents including charcoal, clay, and clay minerals to adsorb rotavirus and coronavirus in vitro. Results revealed that all the adsorbent agents had good to excellent capability of adsorbing rotavirus and excellent capability of adsorbing coronavirus. Percent adsorptions ranged from 78.74% to 99.89% for rotavirus and 99.99% for coronavirus; while sand (negative control) was < 0.01%. A high affinity binding was present as determined by a low percent desorption (0.06-3.09%). However, the adsorbent bound virus complex retained, and may have actually enhanced, infectivity.  相似文献   
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A series of fatigue-crack growth rate (FCGR) tests was carried out on 8090 Al-Li plate to examine the effects of specimen orientation on fatigue-crack growth. The directionality of fatigue fracture behavior is found to be related to the strong {110}〈112〉 texture in this alloy. Based on a previously developed transgranular FCGR model using restricted slip reversibility (RSR) concepts, [1] a mechanistic model is developed for transgranular fatigue-crack growth in highly textured materials. The model takes the form of the Paris relationship with a power law exponent of 3, and the material texture is shown to strongly influence the proportional factor. The effect of texture on FCGR is related through a geometric factor cos2 ϕ, where ϕ defines the angle between the load axis and the normal of the favorable slip plane. The effect of specimen orientation on FCGR in 8090 Al-Li alloy is shown to be related to a combination of its anisotropic mechanical properties and the variation of angleϕ with specimen orientation. The model further predicts that fatigue-crack growth rates will be slower in many textured materials than texturefree materials becauseϕ > 0 and cos2 ϕ < 1.  相似文献   
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This paper presents an overview and personnal perspective on recent developments and current practice in computer process model. The basic concepts behind conventional process control are reviewed to provide a starting point for the non-control specialist and process engineer. The ensuing sections on Internal Model Control (IMC), Model Predictive Control (MPC) and adaptive control illustrate the evolution of control technology from the traditional multiloop strategies to the modern, multivariable, model-based, computer control systems now being used in industry. The paper does not provide a complete, critical review of process control. However, the discussion and the recommended references should provide a good starting point for anyone wanting to become familiar with current practice and some of the new directions of process control.  相似文献   
18.
The first observation is reported of ultrafast all-optical switching in an integrated asymmetric Mach-Zehnder interferometer, using the nonresonant nonlinearity in Ga/sub 0.82/Al/sub 0.18/As below half the bandgap. A relative switching fraction of more than 80% has been achieved using 330 fs pulses at around 1.55 mu m from a coupled-cavity mode-locked colour centre laser.<>  相似文献   
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The relationship of depressed mood to cognitive disturbance in HIV infection was examined in a sample of 139 homosexual men. Ss were grouped according to the classification of the Centers for Disease Control: 39 were in Group IV, 62 were in Group II or Group III, and 38 were HIV-negative. Ss completed the Profile of Mood States and 10 neuropsychological tests. Analysis employing a classification approach indicated that, although symptoms of depression and neuropsychological impairment were more common in Ss who were HIV-positive, particularly those classified as Group IV, there were no systematic relationships between depression and neuropsychological impairment. Depressed mood and cognitive disturbance each seem to have unique associations to HIV illness status. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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