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121.
The effect of iodine deficiency (ID) on thyroid function in African women during pregnancy and postnatal period was examined, for which very limited information is available. Serum T4, T3, TSH, TBG, thyroxine binding capacity (TBK), free thyroxine index (FT4I=T4/TBK) and T4/TBG were determined by ELISA technique in 32 pregnant women (resident of Plateau state, Nigeria- an ID zone) through pregnancy upto term delivery, and in 5 women up to 6 weeks post delivery. Urinary iodide level was measured at delivery to determine the degree of iodine deficiency. Results were matched with a non pregnant control comprising 44 subjects. 5555 birth weights (BW) of term babies in the region were analysed to determine the prevalence of ‘small for dates’ (SFD) babies in the population. Results show that the level of serum FT4I was elevated very significantly at late gestation (P<.001) but the women were not hyperthyroid, suggesting a marked disturbance in binding of T4 with TBG during pregnancy. Five women with SFD babies were found in ‘compensated hypothyroid state’ and showed a significant depression (p<.01) in serum T4/TBG, T4, FT4I and T3 levels to a low normal range, with a concurrent significant rise (p.<.001) in TSH level (above normal range) throughout pregnancy. Incidence of SFD babies was higher (p.<.001) in ID zone (Bassa 15.2%) compared to control zone (Jos 9.8%). It is concluded that a state of maternal ‘subclinical (compensated) hypothyroidism’ during pregnancy possibly plays an important role in the aetiopathogenesis of SFD babies in Africans. A normal reference range for thyroid parameters at various stages of pregnancy in healthy African women is established for the first time.  相似文献   
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Conclusions The findings of this study revealed that the science and education faculties of are more apt to use audiovisual media than the other faculty members. Transparencies, 16 mm films, and video programs are the most frequently used media. In general, the faculty believed that audiovisual media made significant contributions in the teaching/learning process. They also indicated some obstacles to the utilization of audiovisual media such as: lack of time to select and preview materials; the language of materials; and insufficient variety of materials to correlate with the curriculum. The majority of faculty members indicated that educational technology services are very adequate, while one third of the faculty did have problems particularly in the production of audiovisual materials. Almost half of the faculty members cannot operate one or more categories of audiovisual equipment.  相似文献   
124.

The field of adaptive e-learning is continuously developing. More research is being conducted in this area as adaptive e-learning aims to provide learners with adaptive learning paths and content, according to their individual characteristics and needs, which makes e-learning more efficient and effective. The learner model, which is a representation of different learner’s characteristics, plays a key role in this adaptation. This paper presents a systematic literature review about learner modelling during the last 5 years, describing the different modelled characteristics and the adopted modelling techniques and modeling types: automatic modeling and collaborative modeling. 107 publications were selected and analyzed, and six categories of the modelled characteristics were identified. This literature review contributes to the identification of the learners’ individual traits and presents the most used modelling techniques for each of them. It also identifies the latest research trends of Learner Modeling and generates future research directions in this field.

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125.
This one-year collaborative study examined the role of narrative in promoting new forms of culturally responsive literacy learning in two contrasting international preschool contexts. The qualitative project was carried out by a U.S.-based teacher educator and a Palestinian-based teacher educator who examined the benefits of culturally responsive children's literature, child-centred and open-ended questions, narrative-based dictation and art activities, and co-constructed stories between parents and children. The findings indicate that small-scale changes in the use of narrative in literacy pedagogy can strengthen the classroom as a literacy community, foster culturally valued modes of thinking that deepen children's connections to stories, and strengthen children's engagement with a culturally responsive sense of aesthetic representation. The study's implications emphasise the power of narrative to deepen young children's engagement with literacy in contrasting international settings, and the productive role of cross-cultural collaborative research to diversify current definitions of high-quality early literacy education at the global level.  相似文献   
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We report data on Portuguese understandings of interpersonal arguing, based on a survey conducted in Portugal (N?=?252). Employing concepts and methods developed for studying interpersonal arguing, we report on the levels of argumentativeness, verbal aggressiveness, personalization of conflict, and argument frames. After comparing Portuguese men and women, we compare Portuguese respondents with two groups of US respondents. In contrast to US respondents, Portuguese report to argue more prosocially, cooperatively and civilly, and are more sophisticated in their reflections about arguing. We discuss these results in the context of the Portuguese notion of argumentation (argumentação) and Portuguese culture more broadly.  相似文献   
128.
High quality summary is the target and challenge for any automatic text summarization. In this paper, we introduce a different hybrid model for automatic text summarization problem. We exploit strengths of different techniques in building our model: we use diversity-based method to filter similar sentences and select the most diverse ones, differentiate between the more important and less important features using the swarm-based method and use fuzzy logic to make the risks, uncertainty, ambiguity and imprecise values of the text features weights flexibly tolerated. The diversity-based method focuses to reduce redundancy problems and the other two techniques concentrate on the scoring mechanism of the sentences. We presented the proposed model in two forms. In the first form of the model, diversity measures dominate the behavior of the model. In the second form, the diversity constraint is no longer imposed on the model behavior. That means the diversity-based method works same as fuzzy swarm-based method. The results showed that the proposed model in the second form performs better than the first form, the swarm model, the fuzzy swarm method and the benchmark methods. Over results show that combination of diversity measures, swarm techniques and fuzzy logic can generate good summary containing the most important parts in the document.  相似文献   
129.
1 Introduction Thesuccessfulcommericalapplicationsofwirelesstechnologydemandappropriateantennas.Typically,adualpolarizationoperationsuchassimultaneousvertialandhorizontalpolarizationantennawithlowprofile,smallsize,andlightweightisrequiredforwidespre…  相似文献   
130.
The present study was undertaken to evaluate antidiabetic and antioxidant activities of Cayratia trifolia root extract against streptozotocin induced diabetes in experimental rats to scientifically validate its use against diabetes in some parts of India. Ethanolic extract, showing the highest activity in in vitro experiments, was prepared in saline and administered orally to streptozotocin induced albino Wistar diabetic rats for 21 days. Biochemical parameters liver and muscles glycogen and in vivo antioxidant activity in normal, diabetic control, standard (metformin) and treated animals were determined and compared. Attempt was made to isolate, purify and characterize one of the major secondary metabolites in extract by range of chromatographic and spectroscopic techniques. Treatment of streptozotocin induced diabetic rats with ethanolic root extract (500 mg/kg) caused significant (P < 0.01) reduction in blood glucose (312–178 mg/dL), increase in body weight (181–219 g) and serum insulin (1.28–2.26 IU/dL). It also maintained lipid profile and tests of liver and kidney functions within normal range as compared to diabetic control rats and almost at par with standard drug metformin. The oxidative stress induced decline in glutathione and catalase in liver and kidney tissues showed recovery nearly to normal level as a function of treatment. The GC–MS profile of the extract showed relatively high concentration of β-sitosterol which was characterized by different spectroscopic and chromatographic techniques. The result scientifically and comprehensively validate the reported use of roots of this indigenous plant against diabetes. A strong antioxidant activity of the ethanolic root extract suitably compliments the antidiabetic effect.  相似文献   
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