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121.
122.
In order to examine factors that may deter girls' interest in science, five seventh-grade life science textbooks were analyzed for sexism in language, images, and curricular content, and for features of activities that have been found to be useful for motivating girls. Although overt sexism was not apparent, subtle forms of sexism in the selection of language, images, and curricular content were found. Activities had some features useful to girls, but other features were seldom included. Teachers may wish to use differences that were found among texts as one basis for text selection.  相似文献   
123.
With the currently dwindling traditional applicant pool, retention is higher education's holy grail of the nineties. Western Psychological Services is marketing its new Student Adaptation to College Questionnaire (SACQ) as providing early evidence of poor adjustment and potential attrition. While the SACQ closely parallels Tinto's model of institutional departure, no previously published research addresses its ability to differentiate persisters from nonpersisters. Using discriminant analysis, the present study examined (1) the extent to which the SACQ accurately predicts student departure for a private, comprehensive university; (2) SACQ items distinguishing nonpersisters; (3) use with an incoming class; and (4) evidence linking the SACQ with intervention strategies. The paper will appeal to a wide audience, especially those concerned with enrollment management and assessment.Presented at the Thirty-first Annual Forum of the Association for Institutional Research, San Francisco, May 26–29, 1991.  相似文献   
124.
The goal of our study was to compare the working conditions, salary size, and professional outcomes of teachers at schools that switched to the competitive performance-based (so-called ‘effective’) contract in comparison with teachers at schools that did not switch to this employment framework. The study focused on teachers at 83 vocational secondary schools (VSS) that are subordinate to the Ministry of Education of Moscow Region. We conducted an opinion poll to obtain direct information from teachers. We sent questionnaires consisting of 31 questions to 253 teachers. Of the respondents, 105 were included in the experimental group and 148 were placed in the control group. The results of our study show that teachers who work in organizations that have switched to the effective contract model have a higher subjective assessment of their own financial situation, greater expectations regarding their future income, greater confidence about the compensation plan, and a better opinion of the prestige of the teaching profession than teachers at schools that have not adopted an effective contract. The only parameter that cannot be interpreted as an unambiguously positive result is an increase in the frequency of teacher performance assessments at schools that have adopted an effective contract. It was also possible to establish the existence of a moderate relationship between the individual nature of the employment contract and the level of trust that teachers have in their compensation plan. In addition, we established another moderate relationship between informedness and the level of trust that teachers place in their compensation plan. Thus, we can recommend implementing the performance-based contract model at all VSS in the Moscow Region, because it has a positive impact on the immaterial motivation and financial position of teachers. By conducting additional measures to increase teachers’ informedness about effective contracts, we can increase their level of trust in them.  相似文献   
125.
This article addresses the need for changes in current views on adolescent development. It presents observations of adolescent behavior in the online game Dragon Nest that were conducted by specialists from the Crossroads Center for Social and Psychological Adaptation and Adolescent Development, Moscow State University of Psychology and Education, in 2013. These observations helped form theories about age-specific tasks arising in adolescence. The restorative approach was selected as the theoretical basis for this work. This approach represents the practical application of the cultural-historical theory and the activity theory to the provision of social and psychological assistance to adolescents. An analysis of adolescent activity in a game, the structure of communication, and observations of adolescent relationships in online gaming space make it possible to form theories on the role of communication among peers in today’s society in terms of adolescent individuation and development.  相似文献   
126.
In this paper a method for the realization of RC transfer immittance functions with an unsymmetrical lattice is presented. The method yields minimal capacitor realizations for Z12(s) with no pole at s = 0 and ?y12(s) having no pole at s = ∞. The number of resistors needed are only two more than the minimum needed.  相似文献   
127.
Ovarian cancer is the leading cause of death from gynecological malignancies in women. The primary challenge is the detection of the cancer at an early stage, since this drastically increases the survival rate. In this study we investigated the dielectrophoretic responses of progressive stages of mouse ovarian surface epithelial (MOSE) cells, as well as mouse fibroblast and macrophage cell lines, utilizing contactless dielectrophoresis (cDEP). cDEP is a relatively new cell manipulation technique that has addressed some of the challenges of conventional dielectrophoretic methods. To evaluate our microfluidic device performance, we computationally studied the effects of altering various geometrical parameters, such as the size and arrangement of insulating structures, on dielectrophoretic and drag forces. We found that the trapping voltage of MOSE cells increases as the cells progress from a non-tumorigenic, benign cell to a tumorigenic, malignant phenotype. Additionally, all MOSE cells display unique behavior compared to fibroblasts and macrophages, representing normal and inflammatory cells found in the peritoneal fluid. Based on these findings, we predict that cDEP can be utilized for isolation of ovarian cancer cells from peritoneal fluid as an early cancer detection tool.  相似文献   
128.
Television     
This paper gives an outline of a new television system developed in the laboratories of RCA Victor Company, in Camden, N. J.The system is truly electrical and employs only electronic devices, without a single mechanically moving part.The translation of the visual image is accomplished by means of a vacuum tube called the iconoscope. This tube is a virtual electric eye and consists of a photo-sensitive mosaic corresponding to the retina of the human eye, and a moving electron beam representing the nerve of the eye. The image is projected optically on the mosaic and transformed within the tube into a train of electrical impulses, representing the illumination of individual points of the image.The reproduction of the image is accomplished by means of another vacuum tube, the kinescope, which transforms the electrical impulses back into the variation of light intensity through the bombardment of a fluorescent screen by the moving electron beam.The movement of the electron beams in both tubes, which is responsible for both transformations, is linear and divides the picture into a series of parallel lines. The movements are synchronized so that the instantaneous position of the beams with respect to a point in the picture is always identical. The synchronization is transmitted together with the picture signals, and operation of the receiver is completely automatic.The sensitivity of the iconoscope, at the present time, is approximately equal to that of a photographic film operating at the speed of a motion picture camera, permitting the transmission of outdoor scenes. The resolution is high, much higher than necessary for television images of the highest quality.The paper describes the theory of the system, its characteristics, mode of operation, and includes photographs of images obtained on the fluorescent screen of the receiver.  相似文献   
129.
Oxidative stress was studied by estimating plasma levels of malondialdehyde (MDA), beta carotene, vitamin E and erythrocytic superoxide dismutase(E-SOD) activity in 50 cases of carcinoma of upper digestive tract which included carcinoma of oral cavity, pharynx and oesophagus. While plasma MDA level was found to be increased (3.5±1.0 nmole/ml), a significant decrease in beta carotene (81.2±14.5mg%), vitamin E (8.5±1.1 mg/L) level and E-SOD activity (657.0±80.6 U/G Hb) were observed in carcinoma of upper digestive tract. Patients were treated with radiotherapy which itself was toxic enough and produced its deleterious effects by generation of reactive oxygen species (ROS). As antioxdiants can detoxify ROS, beneficial effect if any, of antioxidant administration during radiotherapy was studied in two groups of patients, group A (n=5, supplemented with antioxidants) and group B (n=5, without antioxidant supplementation). Plasma MDA level was found to be elevated in both the groups but the increase in group B was significant, compared to pretreatment level. Further, body weight was found to be significantly decreased in group B patients, which was maintained in group A patients. Moreover, group A patients showed significant elevation in beta carotene concentration, thus showing beneficial effect of administration of antioxidants during radiotherapy without disturbing the desirable therapeutic effect of radiotherapy.  相似文献   
130.
The present study comprised 100 patients of essential hypertension who were screened for fasting hyperinsulinemia, which was detected in 77% cases. Twenty such hyperinsulinemic cases were subjected to 4 weeks of dietary control phase followed by 6 weeks of omega-3 fatty acids substitution [either 0.6 g/d (group 1) or 1.2 g/d (group 2)]. The mean basal fasting plasma insulin levels were significantly higher (p<0.001) in patients of hypertension when compared to normal controls (126.51±80.36 and 19.35±12.61 μU/ml respectively). At the end of 4 weeks of diet control only, no significant change was observed in any parameter. After substitution of omega-3 fatty acid, a significant reduction of fasting plasma insulin levels in both group 1 (29%) and group 2 (22.8%) was observed (p<0.001). Significant reduction of systolic and diastolic blood pressure (16.4% and 25% respectively), serum cholesterol, triglycerides and low density lipoprotein was also noted in both groups (p<0.001), while high density lipoprotein increased by ∼8 mg% in both groups. Thus omega-3 fatty acid substituion in low dose along-with curtailment of dietary omega-6 fatty acid may be used as an adjunctive measure in the management of essential hypertension.  相似文献   
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