An analytical technique to find approximate solutions of nonlinear damped oscillatory systems

Combining Krylov-Bogoliubov-Mitropolskii (KBM) and harmonic balance methods, an analytical technique is presented to determine approximate solutions of nonlinear oscillatory systems with damping. The first approximate perturbation solutions in which the unperturbed solutions contain two harmonic terms agree with numerical solutions nicely even if the damping force is significant. With suitable examples it has been shown that the combination of classical KBM and harmonic balance methods sometimes fails to measure satisfactory results; but the combination of extended KBM method (by Popov) and harmonic balance method always give the desired results. The method is illustrated by several examples and the solutions are compared to some existing solutions.     

Use of on-line databases by faculty members and research scholars of Jawaharlal Nehru University (JNU) and Jamia Millia Islamia (JMI), New Delhi (India): A survey

The study is focused on finding out the level of use of on-line databases by faculty members and research scholars of the Jawaharlal Nehru University (JNU) and Jamia Millia Islamia (JMI), Delhi (India). Both are Central Universities and are funded by the University Grants Commission (UGC). A well-structured questionnaire was administered to faculty members and research scholars of the JNU and JMI to collect data regarding the use of on-line database. The survey reveals that all of the faculty members and research scholars are aware of the availability of on-line databases and largely use them for reference purposes in their research work and studies. The degree of usefulness and utilization of on-line databases is high among the universities' faculty members and research scholars. The survey further reveals that the respondents from both universities are aware of the search options for accessing on-line databases. It is also found that a large number of respondents of JNU and JMI are using field searching and Boolean operators to access information from on-line databases.     

Status of Serum Calcium,Vitamin D and Parathyroid Hormone and Hematological Indices Among Lead Exposed Jewelry Workers in Dhaka,Bangladesh

Jewelry utilizes lead either directly or as a base metal. Costume jewelry requires lead before molding and plating the product with valuable metals. Therefore, such ornaments have a great potential to release heavy metals having health hazards. Also, jewelry makers engaged in preparing German silver, an alloy, apply lead in smelting, alloying, rolling and milling silver wires and pieces. The metal is taken up by blood, soft tissues and bone. The biological effects of lead are dependent upon the level and duration of exposure. Lead inhibits three enzymes of heme biosynthesis- δ-amino-levulinic-acid dehydratase (ALAD), coproporphyrin oxidase, and ferrochelatase, impairing heme synthesis and depressing serum level of erythropoietin resulting in decreased hemoglobin synthesis. Lead exposure also affects calcium metabolism and impair the synthesis of Calcitriol. In the present study, jewelry makers from Dhaka, Bangladesh, were shown to have significantly high levels of lead, protein, albumin, and parathormone in their blood, and significantly high amount of zinc-protoporphyrin and δ-amino-levulinic-acid in their urine. The control group, on the other hand showed significantly higher amounts of calcium (both total and ionized form) Vitamin D₃ and non-activated erythrocyte ALAD in their blood, along with hemoglobin. It might be due to inhibition of 1-α-hydroxylase enzyme in renal tubules. Lead causes nephro-toxicity and inhibits 1-α- hydroxylase enzyme leading to decreased calcitriol synthesis resulting in impaired calcium absorption across gastro-intestinal tract and renal tubules. Low Vitamin D₃ and significantly increased Parathyroid hormone (PTH) in study group has been found.     

Association of Vitamin D Receptor (FokI and BsmI) Gene Polymorphism with Bone Mineral Density and Their Effect on 25-Hydroxyvitamin D Level in North Indian Postmenopausal Women with Osteoporosis

Osteoporosis is a systemic disease with a strong genetic component. Vitamin D receptor (VDR) has been suggested as a candidate gene for osteoporosis. Therefore the present study was aimed to investigate the pattern of allelic variants of VDR gene polymorphism (FokI and BsmI), its influence on vitamin D levels and bone mineral density (BMD) in North Indian postmenopausal women with osteoporosis for possible genetic association. 254 postmenopausal osteoporotic women and 254 postmenopausal non osteoporotic women were included in the study. VDR FokI and BsmI gene polymorphism gene were assessed by the PCR-RFLP method. Serum 25-hydroxyvitamin D was measured by the ELISA. BMD at the L₁–L₄ lumbar spine, hip, forearm and femoral neck was assessed by dual energy X-ray absorptiometry. The average BMD at spine and hip in postmenopausal women with bb and spine, hip, femoral neck and forearm with ff genotype had significantly low BMD. The frequency of ff genotype and f allele was significantly higher in postmenopausal osteoporotic women when compared with postmenopausal non osteoporotic women. However, no significant association was found between the genotypes and vitamin D levels. Our study reveals that VDR gene FokI and BsmI polymorphism is significantly associated with low bone mineral density. Therefore the ff genotype and f allele of VDR FokI gene may be used as an important risk factor for osteoporosis.     

The Effects of Socio-scientific Instruction on Pre-Service Teachers’ Sense of Efficacy for Learning and Teaching Controversial Family Health Issues

This research investigates the effects of socioscientific instruction on pre-service teachers’ sense of efficacy in the teaching and learning of controversial family health issues. For this purpose, a total of 251 students from two teacher training colleges participated in the study and were randomly assigned as experimental and control groups. The experimental group was taught the contents of the controversial family health issues using socioscientific instruction approach and the control group was taught the same content using a more traditional approach. Quantitative data were obtained from both groups after responding to the ‘Teacher sense of Efficacy Scale’ as instrument used for data collection before and after the treatments. Analysis of covariance was used in data analysis of which the pre-treatment scores were used as covariates. Qualitative interviews were conducted with ten participants randomly selected from the experimental group before and after the treatment to deepen and elaborate the quantitative data. The quantitative and qualitative findings indicate that the integration of the socioscientific instruction have significantly affected the pre-service teachers’ sense of efficacy in favour of the experimental group that shows a more stronger sense of efficacy. It was concluded that the socioscientific instruction is significantly effective in changing the pre-service teachers’ weaker sense of efficacy to a stronger one in the controversial family health issues.     

Framing controversy over language policy in Malaysia: the coverage of PPSMI reversal (teaching of mathematics and science in English) by Malaysian newspapers

In 2003, the Malaysian Government announced the policy of Teaching of Mathematics and Science in English [ETeMS or better known by its Malay acronym, Pengajaran dan Pembelajaran Sains dan Matematik dalam Bahasa Inggeris (PPSMI)]. The policy has, however, caused a furore, with both Malay nationalists and Chinese educationists treating the decision as an attack on their identity. Later in July 2009, the Malaysian Government announced to reverse the PPSMI policy starting from 2012. Researchers have long understood news as an artefact of a socially constructed reality. In making news, journalists shape a reality that reflects the political economic and ideological boundaries within which they work. By employing framing as the theoretical framework and content analysis as the research method, this study examined what pictures newspapers have created for citizens' understanding of the reversal of PPSMI policy. It was found that the mainstream newspapers framed the issue in similar ways, which was to explain and justify the reversal. Meanwhile, the alternative newspaper reflected what was mostly left outwhile the alternative newspaper reflected what was mostly left out and provided a counter-hegemonic discourse.     

Review:On dendritic cell-based therapy for cancers

Dendritic cells(DCs),the most prevalent antigen-presenting cell in vivo,had been widely characterized in the lastthree decades.DCs are present in almost all tissues of the body and play cardinal roles in recognition of microbial agents,autoantigens,allergens and alloantigen.DCs process the microbial agents or their antigens and migrate to lymphoid tissues topresent the antigenic peptide to lymphocytes.This leads to activation of antigen-specific lymphocytes.Initially,it was assumedthat DCs are principally involved in the induction and maintenance of adaptive immune responses,but now it is evident that DCsalso have important roles in innate immunity.These features make DCs very good candidates for therapy against variouspathological conditions including malignancies.Initially,DC-based therapy was used in animal models of cancers.Data fromthese studies inspired considerable optimism and DC-based therapies was started in human cancers 8 years ago.In general,DC-based therapy has been found to be safe in pati