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51.
52.
K. Hussain Reddy 《Resonance》2011,16(12):1273-1283
Vitamin B12 is an important coordination compound in biology. It is an interesting biomolecule in the sense that no other vitamin contains a metal ion. This is the only naturally occurring organometallic compound found in biology. An intriguing aspect of vitamin B12 is the great stability of the metal-carbon bond. A great deal of new and interesting inorganic chemistry has been uncovered while studying systems pertinent to B12. In this article some salient features of this unique molecule (B12) and its model compounds are presented.  相似文献   
53.
Both classroom instruction and lexical database development stand to benefit from applied research on sign language, which takes into consideration American Sign Language rules, pedagogical issues, and teacher characteristics. In this study of technical science signs, teachers' experience with signing and, especially, knowledge of content, were found to be essential for the identification of signs appropriate for instruction. The results of this study also indicate a need for a systematic approach to examine both sign selection and its impact on learning by deaf students. Recommendations are made for the development of lexical databases and areas of research for optimizing the use of sign language in instruction.  相似文献   
54.
The present study was designed to understand the cigarette smoking-induced alterations in hormones and the resulting changes in platelet serotonin (5-hydroxytryptamine, 5-HT) and monoamine oxidase (MAO-B) activity in chronic smokers. Human male volunteers aged 35 ± 8 years, were divided into two groups, namely controls and smokers (12 ± 2 cigarettes per day for 7–10 years). Results showed that cigarette smoking significantly (p < 0.05) elevated plasma triiodothyronine (T3), cortisol and testosterone levels with significant (p < 0.05) reduction in plasma tryptophan and thyroxin (T4). Moreover, smokers showed reduced platelet 5-HT levels and MAO-B activity. In smokers, plasma cortisol was negatively correlated with tryptophan (r = −0.386), platelet MAO-B (r = −0.264), and 5-HT (r = −0.671), and positively correlated with testosterone (r = 0.428). However, testosterone was negatively correlated with platelet MAO-B (r = −0.315), and 5-HT (r = −.419) in smokers. Further, smokers plasma T3 levels were negatively correlated with platelet MAO-B (r = −0.398), and 5-HT (r = −0.541), whereas T4 levels were positively correlated with platelet MAO-B (r = 0.369), and 5-HT (r = 0.454). In conclusion, our study showed that altered testosterone and cortisol levels may aggravate behavior, mood disturbances and symptoms of depression by decreasing platelet 5-HT and MAO-B activity in smokers.  相似文献   
55.
Type 2 diabetes mellitus (DM) is a multifactorial disease where both genetic and environmental factors contribute to its pathogenesis. Estrogen plays an important role in type 2 DM pathogenesis. A number of polymorphisms have been reported in the estrogen receptor (ESR1), including the XbaI and PvuII restriction enzyme polymorphisms of ESR1,which may be involved in disease pathogenesis. Metallothioneins (MT) act as potent antioxidants against various oxidative damages. Very few studies have indicated the association between Estrogen Receptor-α, MT1 gene polymorphisms with type2 DM. A total of 100 type 2 diabetic women and 100 age, sex matched controls were recruited. Using the PCR based RFLP method, the PvuII and XbaI polymorphisms of ESR1 and in MT1A (rs8052394 and rs11076161) gene polymorphisms were analysed. The genotype distribution and frequency of mutated allele showed no significant differences between diabetic and non-diabetic groups in PvuII (χ2 = 2.443; P = 0.1181) or XbaI (χ2 = 1.789; P = 0.1812) and rs8052394 (χ2 = 1.154; P = 0.2840) or rs11076161 (χ2 = 0.4141; P = 0.5199), polymorphisms. This is the first Indian study to conclude that ESR1 and MT1 gene polymorphisms are not associated with increased susceptibility to type 2 diabetes in Indian women.  相似文献   
56.
We examine the impact of teacher professional development on a key aspect of teacher quality—teacher knowledge. Specifically we use English Language Arts teacher content and pedagogy assessments to determine whether the California Professional Development Institutes significantly improve teacher content knowledge and whether teachers retain that knowledge six months after the institutes are completed. The results indicate that teachers vary significantly in pre-institute knowledge on the four assessed domains, that they demonstrate significant knowledge growth between the pre- and post-assessments, but that practical classroom experience hinders knowledge retention as measured six months later. Further, pre-exiting knowledge gaps are not systematically reduced thereby not alleviating the uneven distribution of teacher quality among California elementary schools.  相似文献   
57.
The health benefits of playing football and the importance of exercise and social contact for healthy ageing are well established, but few older adults in the UK take enough exercise. Football is popular, flexible in format and draws players into engrossing, effortful and social exercise, but the physical demands of play at full speed may make it unsustainable for some older adults. Restricted to walking pace, will play still be engaging? Will health benefits be retained? Will physical demands remain manageable? This pilot study aims to investigate: (1) the experience of older adults playing walking football every week, is it sustainable and rewarding, (2) the intensity and locomotor pattern of walking football, (3) the scale and nature of walking football health benefits and (4) possible cognitive benefits of playing walking football through measures of processing speed, selective and divided attention and updating and inhibition components of executive function. ‘Walking football’ and ‘waiting list’ groups were compared before and after 12 weeks of one-hour per week football. Walking football was found to be engaging, sustainable for older adults and moderately intensive; however, selective health and cognitive benefits were not found from this brief intervention.

Highlights

  • Walking football is a lower impact but authentic form of football that enables older players to extend their active participation.

  • Walking football is enjoyable and moderately demanding and may be a sustainable form of exercise for older adults.

  • Health and cognitive benefits to playing walking football were not found.

  相似文献   
58.
Lymphatic filariasis is a major public health problem in India with 412 million people living in bancroftian endemic areas and is a major cause of clinical morbidity. Twenty million people are reported to suffer from chronic disease manifestations such as lymphoedema, hydrocele or elephantiasis. At least twice the number have been shown to suffer from acute and occult filarial infections in an endemic area without diagnosis. Due to non-availability of suitable diagnostic test for confirming filaria aetiology other than parasitological examination, no significant study on filariasis in children has been reported earlier. Studies in our laboratory for more than a decade showed usefulness of microfilarial excretory-secretory antigen in confirming filarial aetiology in acute and occult infections in adults as well as in children. This study reports acute and atypical manifestations such as lymphadenopathy, asthmatic bronchitis, pulmonary eosinophilia, mono-arthritis, recurrent URI, pneumonia, nutritional anemia, pain in abdomen etc. in children living in filaria endemic area having no microfilaraemia but showing filaria aetiology by immunomonitoring for the presence of antibody or antigen and responding to optimal DEC therapy.  相似文献   
59.
The United States is in an era of high-stakes evaluation of educators (i.e., teachers and principals), the results of which are used to inform human capital decision making (i.e., recruitment, hiring, retention, and dismissal), which in turn impacts school capacity and student learning. The present article describes the School System Improvement (SSI) Project, a school-wide educator evaluation initiative that includes 22 high-poverty schools. The primary goal is to present the Year 1 planning for implementation of educator evaluation, highlighting the use of system consultation for planning. The SSI Project team includes researchers in school psychology and special education, school administrators, and teachers. The project aims to implement a multimethod educator evaluation system that generates scores for informing targeted, evidence-based professional development. Project goals are to increase educator competencies that lead to improved student achievement. Finally, directions for training and recommendations for future school reform are presented.  相似文献   
60.
In many countries, governments are keen to persuade teachers at all levels to seek to enhance the learning of their students by incorporating information and communication technologies within their classrooms. This paper reports on the development of collaborative approaches to supporting use of the Internet by Post Graduate Certificate of Education (PGCE) science students on initial teacher education (ITE) courses in England, drawing on data from five higher education institution (HEI)–school partnerships across four years. A mixed-method approach was used, involving questionnaires, structured interviews, lesson observations and case studies. The outcomes of the first three years identified barriers to practice and suggested the need to develop more collaborative approaches to development. The focus of this paper is on examining ways in which university faculty tutors and mentors or cooperating teachers can work together with students on PGCE courses in developing practice. The lessons from this focus on the Internet, no longer a new technology, have enabled us to identify implications for HEI partnerships in ITE and suggest a need for further collaborative structures in order to support and develop practices, including those involving the innovative use of new technologies in the post-industrial society.  相似文献   
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