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ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the - scattered - experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes.
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OBJECTIVE: To assess the effectiveness of facility-based care for children with severe acute malnutrition (SAM) in Nutrition Rehabilitation Centers (NRC). DESIGN: Review of data. SETTING: 12 NRCs in Uttar Pradesh, India. PARTICIPANTS: Children admitted to NRCs (Jan 1, 2010 - Dec 31, 2011). INTERVENTION: Detection and treatment of SAM with locally-adapted protocols. OUTCOMES: Survival, default, discharge, and recovery rates. RESULTS: 54.6% of the total 1,229 children admitted were boys, 81.6% were in the age group 6-23 months old, 86% belonged to scheduled tribes, scheduled castes, or other backward castes, and 42% had edema or medical complications. Of the 1,181 program exits, 14 (1.2%) children died, 657 (47.2%) children defaulted, and 610 (51.7%) children were discharged The average (SD) weight gain was 12.1 (7.3)g/kg body weight/day and the average (SD) length of stay was 13.2 (5.6) days. 206 (46.8%) children were discharged after recovery (weight gain >15%) while 324 (53.2%) were discharged, non-recovered (weight gain <15%). CONCLUSIONS: NRCs provide life-saving care for children with SAM; however, the protocols and therapeutic foods currently used need to be improved to ensure the full recovery of all children admitted.
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Desnutrição Proteico-Calórica/terapia , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Masculino , Aumento de PesoRESUMO
CdO in the rocksalt structure is an indirect band gap semiconductor. Thus, in order to determine its band gap one needs to calculate the complete band structure. However, in practice, the exact evaluation of the quasiparticle band structure for the large number of k-points which constitute the different symmetry lines in the Brillouin zone can be an extremely demanding task compared to the standard density functional theory (DFT) calculation. In this paper we report the full quasiparticle band structure of CdO using a plane-wave pseudopotential approach. In order to reduce the computational effort and time, we make use of maximally localized Wannier functions (MLWFs). The MLWFs offer a highly accurate method for interpolation of the DFT or GW band structure from a coarse k-point mesh in the irreducible Brillouin zone, resulting in a much reduced computational effort. The present paper discusses the technical details of the scheme along with the results obtained for the quasiparticle band gap and the electron effective mass.
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Compostos de Cádmio/química , Simulação por Computador , Modelos Químicos , Óxidos/química , Teoria Quântica , Eletroquímica , Tamanho da PartículaRESUMO
We present electronic band structures of transparent oxides calculated using the Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. We studied the basic n-type conducting binary oxides In(2)O(3), ZnO, CdO and SnO(2) along with the p-type conducting ternary oxides delafossite CuXO(2) (X=Al, Ga, In) and spinel ZnX(2)O(4) (X=Co, Rh, Ir). The results are presented for calculated band gaps and effective electron masses. We discuss the improvements in the band gap determination using TB-mBJ compared to the standard generalized gradient approximation (GGA) in density functional theory (DFT) and also compare the electronic band structure with available results from the quasiparticle GW method. It is shown that the calculated band gaps compare well with the experimental and GW results, although the electron effective mass is generally overestimated.
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We present the quasiparticle band structure of ZnO in its zincblende (ZB) and rocksalt (RS) phases at the Γ point, calculated within the GW approximation. The effect of the p-d hybridization on the quasiparticle corrections to the band gap is discussed. We compare three systems, ZB-ZnO which shows strong p-d hybridization and has a direct band gap, RS-ZnO which is also hybridized but includes inversion symmetry and therefore has an indirect band gap, and ZB-ZnS which shows a weaker hybridization due to a change of the chemical species from oxygen to sulfur. The quasiparticle corrections are calculated with different numbers of valence electrons in the Zn pseudopotential. We find that the Zn(20+) pseudopotential is essential for the adequate treatment of the exchange interaction in the self-energy. The calculated GW band gaps are 2.47 eV and 4.27 eV respectively, for the ZB and RS phases. The ZB-ZnO band gap is underestimated compared to the experimental value of 3.27 by â¼ 0.8 eV. The RS-ZnO band gap compares well with the experimental value of 4.5 eV. The underestimation for ZB-ZnO is correlated with the strong p-d hybridization. The GW band gap for ZnS is 3.57 eV, compared to the experimental value of 3.8 eV.
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The first institution for training health workers started 75 years ago. Further development of teaching/learning institutions, mainly governmental started from the middle of the 20th Century. It was however with the setting up of the Institute of Medicine (IoM) under TU that training programmes for different grades of health manpower were started. The last two decades has seen an explosion of institutions involved in the training of health personnel. This is possibly because of the huge demand of human resources of health (HRH) not only in Nepal, but worldwide. Various grades of HRH are going out of the country and seeking their livelihood elsewhere.
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Educação Médica/história , Educação Médica/métodos , Educação Médica/organização & administração , Mão de Obra em Saúde/história , Mão de Obra em Saúde/organização & administração , História do Século XX , Humanos , Nepal , Aprendizagem Baseada em ProblemasRESUMO
BACKGROUND: A revolution in health care is occurring as a result of changes in the practice of medicine and in society. Medical education, if it is to keep up with the times, needs to adapt to society's changing attitudes. Presently medical education has been criticised for its orientation and insensitivity to people's need. The MBBS curriculum of medical institutions of Nepal has been focusing on community-based approaches and is still guided by the same notion. The question put forward is whether it has been appropriate to nurture the present health needs and aspiration of people. OBJECTIVE: The objective of the present study is to review the existing community based medical education in health institutions of Nepal to strengthen the components of community care. MATERIALS AND METHODS: Qualitative study was done by reviewing the curricula and existing community medicine courses/activities in MBBS curriculum of Institute of Medicine (IoM)/Tribhuvan University, BP Koirala Institute of Health Sciences (BPKHIS) and Kathmandu University School of Medical Sciences (KUSMS). FINDINGS AND DISCUSSION: The curriculum of all the health institutions have addressed significantly on community medicine practice. As per Institute of Medicine, the community medicine practice is achieved through community based learning experiences like community diagnosis, concurrent field with families of sick members and district health system management practice. In BP Koirala Institute of Health Sciences, community medicine practice is undertaken through exposure to community diagnosis program, health care delivery system, family health exercise, applied epidemiology and educational research methodology, management skills for health services and Community Oriented Compulsory Residential Rotatory Internship Program (COCRRIP). In KUSMS, community medicine module is carried out as- community diagnosis program, community health intervention project, school health project, occupational health project, health delivery system functioning, family health care activities and Compulsory Residential Rotatory Internship Program in outreach clinics. In the practice the practical aspects are largely unstructured that waste too much time in non-educational activities and rely on learning and doing. Meanwhile, expectation of the community is increasing and the challenge of nurturing their demands has come in forefront. Community has perceived that the medical schools are concentrating on fulfilling the demand of their curriculum rather directing on their health care need. CONCLUSION: Health institutions need to be accountable to take the responsibility of strengthening the health status of the community of their catchments areas. The practice of community medicine need to be done in an innovative way and these schools should execute continual intervention activities and complement other institutions working in their areas.
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Medicina Comunitária/educação , Currículo , Educação Médica/organização & administração , Faculdades de Medicina/organização & administração , Serviços de Saúde Comunitária/organização & administração , Atenção à Saúde/organização & administração , Países em Desenvolvimento , Feminino , Reforma dos Serviços de Saúde , Humanos , Masculino , Nepal , Padrões de Prática Médica/organização & administração , Atenção Primária à Saúde/organização & administração , Desenvolvimento de Programas , Avaliação de Programas e Projetos de SaúdeRESUMO
BACKGROUND: Medical schools and medical education look different as we advance into the 21st century. Nepal has seen a dramatic increase in the number of medical schools/colleges in the last decade. Most schools practice traditional teaching method while others are implementing problem based learning (PBL). It is important to explore the current advances and practices in medical education to meet the needs of the health services of the country. OBJECTIVE: The objective of the present study is to explore the students' perception regarding present status of medical education in Nepal and provide recommendations to address future needs. MATERIAL AND METHODS: The study design of the present research was descriptive and exploratory type. Structured Questionnaire was used to assess the students' perception relating to different aspects of medical education. A total of 24 students studying in the final year of MBBS from six medical colleges were selected randomly. RESULTS: The traditional teaching/learning methodologies have been prevailing in the medical schools of the country. PBL suits many objectives of self directed learning (SDL) because students learn to reason and deduce facts and figures rather than rote learning. For the success of PBL and SDL students require learning resources and as per our findings although 71% of the students were satisfied with library facilities 54% were dissatisfied with computer resources. Community based approaches have been focused in the curriculum of all the medical schools of Nepal. About public health and community medicine teaching 86% of the students reported to be appropriate, of which 18% actually thought it was excessive. About the teaching of evidence based medicine (EBM), 50% students felt it was adequate and other half thought it was inadequate. Majority of the students i.e. 62% of the students also felt that the care of ambulatory patients was as well covered as the care of hospitalized patients. The areas of clinical practice which the students felt were inadequate included: nutrition (71%), geriatrics (70%), end of life care (71%), palliative care (67%), long term health care (70%), continuity of care (70%), ethical decision making (56%) and patient follow up (50%). In spite of completing their training, 25% felt they were not confident that they had acquired the clinical skills required to begin the residency program. As much as 60% felt they did not receive information about specialties and alternative medical careers. About 75% of the students had the feeling that medical profession will not be financially rewarding; 80% felt it would not be as respectable; 99% felt it would be more scientifically challenging. CONCLUSION: The medical education of Nepal is still guided by the notion of the traditional approaches. The teaching methods should come up as per the advancement in contemporary medical education. The training needs to be more structured and focused in practical reality than only feeding students with theoretical knowledge.
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Atitude do Pessoal de Saúde , Educação de Graduação em Medicina , Estudantes de Medicina , Competência Clínica , Estudos Transversais , Feminino , Humanos , Masculino , Nepal , Avaliação de Programas e Projetos de SaúdeRESUMO
OBJECTIVE: To analyse the impact of the medical colleges that have been set up within the last two decades by production of the doctors and the effect on the health of the people. MATERIALS AND METHODS: SWOT (strength, weakness, opportunities and threats) analysis of medical education in Nepal has been done by reviewing medical manpower produced by the different institutions in the undergraduate and postgraduate (PG) categories, their registration with the Nepal Medical Council in terms of the existing health scenario of the country. RESULTS: Shows severe shortage of basic sciences teachers. In the clinical areas ophthalmic manpower and services provided are exemplary. There are shortages and shortcomings in all areas if standard health care is to be provided to the Nepalese. There is a long way to go to provide the expected educational and medical services to foreigners prepared to pay more to avail of this in Nepal.
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Educação Médica/organização & administração , Educação Médica/estatística & dados numéricos , Currículo , Mão de Obra em Saúde/estatística & dados numéricos , Humanos , Medicina/estatística & dados numéricos , Modelos Organizacionais , Nepal , Faculdades de Medicina/organização & administração , Faculdades de Medicina/estatística & dados numéricos , Estudantes de Medicina/estatística & dados numéricosRESUMO
OBJECTIVE: To determine the prevalence of anemia and iron status as assessed by biochemical markers and to explore the associations between markers of iron status and iron intake. STUDY AREA AND POPULATION: Five hundred healthy women of reproductive age from the Bhaktapur district of Nepal were included in the study. METHODS: A cluster sampling procedure was applied for this cross-sectional study. Women without any ongoing infection aged 13-35 years were selected randomly from the population. We measured the plasma concentration of hemoglobin (Hb), ferritin and transferrin receptors. Dietary information was obtained by a food frequency questionnaire and two 24-h dietary recalls. RESULTS: The prevalence of anemia (Hb concentration <12 g/dl) was 12% (n=58). The prevalence of depleted iron stores (plasma ferritin <15 microg/l) was 20% (n=98) whereas the prevalence of iron deficiency anemia (anemia, depleted iron stores with elevated transferrin receptor i.e. >1.54 mg/l) was 6% (n=30). Seven percent (n=35) of women were having iron-deficient erythropoiesis (depleted iron stores and elevated transferrin receptor but normal Hb). Out of the 58 anemic women, 41 (71%) and 31 (53%) were also having elevated plasma transferrin receptor and depleted iron stores, respectively. Fifty-four percent of the women ate less than the recommended average intake of iron. The main foods contributing to dietary iron were rice, wheat flour and green and dry vegetables. CONCLUSIONS: The prevalence of anemia in our study was substantially lower than the national figure for non-pregnant women. Only about half of the women with anemia were also having depleted iron stores, suggesting that other causes of anemia may be prevalent in this population. SPONSORSHIP: Norwegian Universities Committee for Development, Research and Education (NUFU).
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Anemia Ferropriva/epidemiologia , Anemia/epidemiologia , Dieta , Ferro , Adolescente , Adulto , Anemia/sangue , Anemia/etiologia , Anemia Ferropriva/sangue , Anemia Ferropriva/etiologia , Análise por Conglomerados , Estudos Transversais , Feminino , Ferritinas/sangue , Hemoglobinas/análise , Humanos , Ferro/administração & dosagem , Ferro/sangue , Deficiências de Ferro , Rememoração Mental , Nepal/epidemiologia , Prevalência , Receptores da Transferrina/sangue , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Elevation of FSH is frequently a consequence of impaired ovarian follicle growth. Down-regulation of the FSH levels by inhibins is mediated through its receptor betaglycan in the gonadotrophs. Understanding of germline status of the betaglycan gene (TGFBR3) is essential for ovarian failure pathophysiology. METHODS: Sequence analysis was performed for the coding region of TGFBR3 gene in a cohort of 196 ovarian failure cases that include 133 premature ovarian failure (POF) cases, 63 primary amenorrhoea (PA) cases compared with 200 controls. RESULTS: Forty-six variants including six novel exonic variants and 16 novel intronic variants were revealed. Two variants were missense: (i) p.Iso184Val in a control and (ii) p.Pro775Ser in a POF case. Genotypic distribution of three variants (c.382-81C>T, c.382-77T>C and c.1200G>A) was significantly different in the patients as compared with the controls. Five variants c.382-81C>T, c.382-77T>C, c.566-216G>A, c.1200G>A and c.2022T>C were chosen for haplotyping. The CCAAT haplotype was significantly higher in the patient population as compared with the controls (P = 0.00007). CONCLUSION: This study establishes the first mutational report of the TGFBR3 gene in correlation with ovarian failure. Significant diversity of genotype distribution and haplotype analysis suggested susceptibility of the TGFBR3 gene for ovarian failure aetiology.
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Predisposição Genética para Doença/genética , Insuficiência Ovariana Primária/genética , Proteoglicanas/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Adulto , Amenorreia/genética , Análise Mutacional de DNA , Feminino , Genótipo , Haplótipos , Humanos , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
BACKGROUND: Clinically, premature ovarian failure (POF) is defined as unexplained amenorrhoea (> 6 months) with a high FSH level (> 40 IU) before the age of 40 years. POF is a heterogeneous genetic disease with unknown aetiology. Inhibin and activin regulate the FSH level by their opposing actions and thus have been considered as strong candidate genes in the aetiology of POF. METHODS: We have screened inhibin genes in patients with POF (n = 80), primary amenorrhoea (n = 33) and secondary amenorrhoea (n = 4). RESULTS: INHbetaB and INHbetaA genes do not show any association with ovarian failure. We found the Ala257Thr missense mutation in INHalpha gene with high statistical significance in POF (nine out of 80, 11.2%) (Fisher's exact test, P = 0.0005), primary amenorrhoea (three out of 33, 9.1%) (Fisher's exact test, P = 0.014) and secondary amenorrhoea (two out of four, 50%) (Fisher's exact test, P = 0.001) with complete absence of this mutation in controls (none out of 100). CONCLUSION: The INHalpha gene is a strong candidate gene for ovarian failure. Mutations in INHbetaB and INHbetaA genes are not associated with ovarian failure.
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Subunidades beta de Inibinas/genética , Inibinas/genética , Insuficiência Ovariana Primária/genética , Adolescente , Adulto , Sequência de Aminoácidos , Análise Mutacional de DNA , Feminino , Humanos , Índia , Dados de Sequência Molecular , Mutação Puntual , Polimorfismo de Fragmento de RestriçãoRESUMO
INTRODUCTION: With the growing awareness of the importance of teaching and learning in Universities, the need to improve professional qualities in teachers has been identified. AIM AND OBJECTIVES: This paper describes the outcome of the impact of teacher training workshops on faculty- teaching performance. METHODOLOGY: A total of 30 faculties who had undergone teacher training in the one-year period were included in the study. Survey questionnaire were distributed and all the forms were returned. RESULTS: All (100%) respondents found the teacher training to be very useful/useful for improvement of teaching skills. A total of 76.66% said that the skills learnt in the workshop were very applicable, 80% perceived changes in students classroom behaviour and found their lecture to be more participatory and interactive. As for their own change in behaviour, 66.66% respondents experienced better interaction with the students in classroom. DISCUSSION: The overall impression of the training was very positive. Future studies should include student feed back and classroom teaching observation for faculty teaching evaluation. We also need to utilise the feed back information obtained in this article, to further improve the strength of the future teacher training workshops. The future workshops should include sessions in problem-based learning and follow up refresher courses.
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Docentes de Medicina , Ensino/métodos , Atitude do Pessoal de Saúde , Coleta de Dados , NepalRESUMO
It is accepted that selecting students for the MBBS course is fairly difficult and not totally effective. This article documents the process undertaken at Kathmandu Medical College (KMC) with reference to previous attempts and suggestions for the future.
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Critérios de Admissão Escolar , Faculdades de Medicina , Feminino , Humanos , Masculino , NepalRESUMO
Though Health Sciences education started in the country as far back as 1934, it was only in 1978 that the MBBS course was started. The first postgraduate (PG) course, which was started, was the MD in general practice, which was started in 1982. It is over the course of the last 22 years, and more specifically after 1993, that there has been a spurt in postgraduate (PG) education. The rapid increase of medical schools/colleges within the country during the last decade, has been the main reason for fulfilling the demand of doctors with postgraduate degrees required for different faculty positions at the newly established medical colleges, This article also looks at the role of foreign qualifications vis-à-vis the local degree for the development of PG programmes within the country.
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Educação de Pós-Graduação em Medicina/organização & administração , Educação de Graduação em Medicina/organização & administração , Avaliação Educacional , Humanos , Nepal , Ensino , Universidades/organização & administraçãoRESUMO
This is an account regarding the intake of the 7th batch of MBBS students at Kathmandu Medical College (KMC) for the academic session 2003-2004. A total of 257 admission forms had been issued to Nepali students. Of these, 252 admission forms were filled up and were submitted to KMC together with the completed questionnaire by the Nepali students. Seven students (approximately 2.7%) did not attend interview. After the interview, out of the 245 interviewed students, the names of only 50 were brought out in the 1st list for admission. The paper presents the system for admission of MBBS students and has made recommendations for future action.