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The differential relations of children's emotion-related regulation (i.e., effortful control and impulsivity) to their personality resiliency, adult-rated popularity, and social competence were examined in children who were 4.5-7.9 years old and who were remeasured 2 years later. Parents and teachers reported on all constructs, and children's attentional persistence was observed. Structural equation modeling was used to test the mediating role of resiliency on the relations between regulation/control and popularity using two-wave longitudinal data. The results provide some evidence of the mediating role of resiliency in the relations between effortful control and popularity, provide some evidence of bidirectional effects, and also buttress the view that emotional regulation should be differentiated into effortful and reactive forms of control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Report of one case of pure yolk sack testicular tumour in an adult patient. This was a stage I case which had been under observation for 3 years without further evidence of disease. Several aspects related with this type of germinal, non-seminomatous tumour of the testicle are commented upon.  相似文献   
4.
A three-dimensional derivative variable-angle synchronous scanning (DVASS) and a synchronous scanning (SS) heavy-atom room-temperature phosphorimetry (HAI-RTP) method are reported, for the first time, to identify and quantify the spectral overlapping phosphorescent pesticides thiabendazole (TBZ) and carbaryl (CBL). These pesticides are widely used in agriculture. The phosphorescence emission of the two compounds was obtained using sodium sulfite as the O2 scavenger and an external heavy atom salt. A careful selection of these experimental variables has been carried out. The increase of selectivity afforded by the DVASS and the SS methodology permitted the demonstration of its applicability to the simultaneous determination of phosphorescent signals of these two pesticides with overlapping spectral profiles. Limits of detection ranged between 1.4 ng/mL for TBZ and 1.7 ng/mL for CBL. The proposed method has been satisfactorily applied to the analysis of both pesticides in different types of water samples.  相似文献   
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INTRODUCTION: Global amnesia (AG) is a dysfunction of memory, in which there is a sudden incapacity to remember recent events and assimilate new information. The aetiology is currently under discussion. The main hypotheses under consideration are an ischemic mechanism and an epileptic mechanism. OBJECTIVE: To study the cerebral blood flow in patients with temporary global amnesia (AGT) or permanent global amnesia (AGP) using functional neuroimaging techniques. MATERIAL AND METHODS: Four patients were studied. Two had severe alterations of fixation memory which had been present for months. The other two had a sudden loss of recent memory, although space-person orientation and immediate memory remained normal. In all cases the cerebral blood flow (FSC), was assessed by single photon emission tomography (SPECT), using Tc-HMPAO as the radio tracer. RESULTS: We describe 4 patients, 2 men and 2 women aged between 42 and 64.2 with AGT and the others with AGP. On SPECT there was temporal hypoperfusion in all 4 patients. In 2 cases there was associated parietal hypoperfusion and in 1 case there was frontal hypoperfusion. CONCLUSIONS: These findings suggest that AGT and AGP are of vascular origin and that SPECT is a useful diagnostic technique in patients with AG.  相似文献   
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The purpose of this study was to evaluate a set of teaching materials on food, nutrition and agriculture, adapted at the Institute of Nutrition and Food Technology (INTA), University of Chile, within the scope of a project with AID and the School of Agronomy of the Chilean Catholic University (U. C.) aimed at incorporating the teaching of human nutrition into the curriculum of Latin American agronomists. A one semester course (54 hours) was given to 22 students of the 7th semester of Agronomy and two Ecuatorian agronomists (with AID scholarships). A set of knowledge evaluation instruments was applied at the beginning and at the end of the course. A total of 83.3% of the students passed the final examination (with more than 75% of correct answers). The difference between the initial and final performance was highly significant (p less than 0.001). According to the students' and teachers' opinions, the general textbook and the teachers book contributed effectively to meet the learning objectives whereas the students handbook needed some modifications. In conclusion, the program is an important contribution to the education of agronomists in a new conception of their role in regard to improvement of the nutritional status and quality of life of the rural population. With a few minor modifications, a final version to be used in the countries of the Region, shall soon become available.  相似文献   
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The extraction of nitric acid and phosphoric acid by tributyl phosphate (TBP), from solutions containing acid mixture and in the presence of nitrate salts, has been studied. The effect of the temperature on acid extraction has been also investigated. It is found that TBP extracts nitric acid preferentially to phosphoric acid, especially in the presence of nitrate salts. The coextraction of nitric acid suppresses the extraction of phosphoric acid. These results were interpreted in terms of common ion effect and variation of the activity coefficients variation in both phases. The simultaneous effects of the salts and acids on the extraction of both acids is also studied

Some tests were carried out, using process solution, to evaluate the extraction of acids. Both batch experiments and continuous tests (using mixer settler) were performed. Some flowsheets were tested in order to improve the extractivity and the selectivity of phosphoric acid. The results show the limitation of TBP for the extraction of phosphoric acid. TBP can be used to selectively extract nitric acid.  相似文献   
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ABSTRACT

This paper reviews the results obtained by studying the dual-temperature ion-exchange fractionation (DTIXF) technique. The DTIXF is based on the use of different affinity at different temperatures of ion exchangers towards ions to be separated. This technique allows to design absolutely reagentless and, as a result, wasteless fractionation technology. The review considers the temperature dependencies of selectivity of commercially available ion-exchange (LX) resins towards components of ionic mixtures of different complexity starting from binary model systems up to naturally existing nonacomponent effluents. A novel approach for predicting the temperature sensitivity of a given LX system is presented and discussed. The same approach has been shown to be applicable for the design of IX resins with temperature-dependent selectivity. The paper also reports the results obtained in the practical application of DTIXF technique for concentration of magnesium from seawater and copper from acidic mine waters. The flowsheets of DTLXF processes are proposed and discussed.  相似文献   
9.
Abstract

The rate of extraction of copper(II) from aqueous chloride solutions by tri-n-laurylammonium chloride (TLAHC1) dissolved in toluene has been investigated. The extraction rate was evaluated as function of the chemical composition of the system. The experiments were performed by using a stirred cell with constant inter-facial area. The experiments were performed at a stirring rate of the two phases where the influence of film diffusion is minimized. The data have been interpreted by a mechanism which assumes interfacial chemical reactions between the bulk species containing copper(II) and the molecules of TLAHC1 absorbed at the interface as rate determining.  相似文献   
10.
This work examines the design method of Eurocode 3 against brittle failure with regard to its application to a high strength structural steel S460N EN 10113 type. The fracture behaviour of the steel is experimentally determined by means of fracture tests, considering also the effects of temperature and plate thickness. A direct verification of the method of Eurocode 3 is made by contrasting the assumptions on which it is based with the actual behaviour of the steel. The failure criterion and the mechanical properties characterizing the resistance to brittle and ductile fracture are the basis of the comparison.
Résumé La méthode de calcul de l’Eurocode 3 en vue de se garantir du risque de rupture fragile est examinée dans cet article, par rapport à l’application à un acier à haute résistance pour construction métallique (l’acier S460N de la norme EN 10113). Les caractéristiques mécaniques de la rupture de l’acier, en particulier l’influence de la température et de l’épaisseur de laminage, ont été déterminées par des essais de rupture sur éprouvettes préfissurées. La méthod de l’Eurocode 3 a été vérifiée de manière directe en comparant les fondements des règles de calcul au comportement mesuré de l’acier. La comparaison est basée sur le critère de rupture mixte (fragile/ductile) adopté par l’Eurocode et sur les valeurs de tenacité établies à partir des valeurs de la résilience.


Editorial Note Prof. M. Elices is a Senior Member and a member of the Board of Advisors. He is a member of RILEM TC 147-FMB: Fracture mechanics applications to anchorage and bond, TC 148-SSC: Test methods for the strain softening response of concrete and TC QFS: Size effect and scaling of quasibrittle fracture.  相似文献   
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