bluuebunny/crossref_metadata_2025 huggingface dataset:
WldS and PGC-1α Regulate Mitochondrial Transport and Oxidation State after Axonal Injury
Authors: O'Donnell Kelley C. , Vargas Mauricio E. , Sagasti Alvaro
Published: September 2013

Mitochondria carry out many of the processes implicated in maintaining axon health or causing axon degeneration, including ATP and reactive oxygen species (ROS) generation, as well as calcium buffering and protease activation. Defects in mitochondrial function and transport are common in axon degeneration, but how changes in specific mitochondrial properties relate to degeneration is not well understood. Using cutaneous sensory neurons of living larval zebrafish as a model, we examined the role of mitochondria in axon degeneration by monitoring mitochondrial morphology, transport, and redox state before and after laser axotomy. Mitochondrial transport terminated locally after injury in wild-type axons, an effect that was moderately attenuated by expressing the axon-protective fusion protein Wallerian degeneration slow (WldS). However, mitochondrial transport arrest eventually occurred in WldS-protected axons, indicating that later in the lag phase, mitochondrial transport is not required for axon protection. By contrast, the redox-sensitive biosensor roGFP2 was rapidly oxidized in the mitochondrial matrix after injury, and WldS expression prevented this effect, suggesting that stabilization of ROS production may mediate axon protection. Overexpression of PGC-1α, a transcriptional coactivator with roles in both mitochondrial biogenesis and ROS detoxification, dramatically increased mitochondrial density, attenuated roGFP2 oxidation, and delayed Wallerian degeneration. Collectively, these results indicate that mitochondrial oxidation state is a more reliable indicator of axon vulnerability to degeneration than mitochondrial motility.
P2X Receptor Intermediate Activation States Have Altered Nucleotide Selectivity
Authors: Browne Liam E. , North R. Alan
Published: September 2013

Purinergic P2X receptors are widely distributed in the nervous system and are known to play roles in primary afferent transmission and central respiratory regulation. They are trimeric membrane proteins, with the extracellular domain that provides three intersubunit ATP binding sites. We expressed the rat P2X7 receptor in human embryonic kidney cells and measured membrane currents before and after photo-affinity labeling with the agonist 2′(3′)-O-(4-benzoylbenzoyl)-ATP (BzATP). After tethering BzATP with ultraviolet light, a persistent current remained after washing out the agonist. Additional current could now be elicited by other nucleotides (CTP and ADP) that are not normally effective as P2X receptor agonists. Similar results were obtained at P2X2 receptors even without previous agonist tethering: exposure to low concentrations of ATP caused the receptor to become sensitive to activation by CTP and ADP. The results show that ATP binding to the first of the three binding sites causes a conformational change to an intermediate closed state that shows increased effectiveness of pyrimidine and diphosphate nucleotide analogs.
Effects of Cathodal Trans-Spinal Direct Current Stimulation on Mouse Spinal Network and Complex Multijoint Movements
Authors: Ahmed Zaghloul
Published: September 2013

Cathodal trans-spinal direct current (c-tsDC) stimulation is a powerful technique to modulate spinal excitability. However, the manner in which c-tsDC stimulation modulates cortically evoked simple single-joint and complex multijoint movements is unknown. To address this issue, anesthetized mice were suspended with the hindlimb allowed to move freely in space. Simple and complex multijoint movements were elicited with short and prolonged trains of electrical stimulation, respectively, delivered to the area of primary motor cortex representing the hindlimb. In addition, spinal cord burst generators are known to be involved in a variety of motor activities, including locomotion, postural control, and voluntary movements. Therefore, to shed light into the mechanisms underlying movements modulated by c-tsDC stimulation, spinal circuit activity was induced using GABA and glycine receptor blockers, which produced three rates of spinal bursting activity: fast, intermediate, and slow. Characteristics of bursting activity were assessed during c-tsDC stimulation. During c-tsDC stimulation, significant increases were observed in (1) ankle dorsiflexion amplitude and speed; (2) ankle plantarflexion amplitude, speed, and duration; and (3) complex multijoint movement amplitude, speed, and duration. However, complex multijoint movement tracing showed that c-tsDC did not change the form of movements. In addition, spinal bursting activity was significantly modulated during c-tsDC stimulation: (1) fast bursting activity showed increased rate, amplitude, and duration; (2) intermediate bursting activity showed increased rate and duration, but decreased amplitude; and (3) slow bursting activity showed increased rate, but decreased duration and amplitude. These results suggest that c-tsDC stimulation amplifies cortically evoked movements through spinal mechanisms.
Villain and Visionary
Authors: Bachrach Eve
Published: September 2013

This article is about the legacy of William Mulholland, engineer of the Los Angeles Aqueduct who was instrumental in building public support for funding and building the project. Supporters hail him as a masterful campaigner and visionary without whom Los Angeles could not have developed into a major city; detractors accuse him of swindling farmers in the Owens Valley out of money and water rights and a puppet of powerful real estate interests in Los Angeles who lied to the public to get voters to support the aqueduct.
Parameters of glycemic control in type 2 diabetic patients on hemodialysis or peritoneal dialysis: implications for clinical practice
Authors: Pavan Maria Valeria , Rodrigues Cibele Isaac Saad , D'Ávila Ronaldo , Guerra Enio Marcio Maia , Cadaval Ricardo Augusto de Miranda , Almeida Fernando Antonio de
Published: September 2013

OBJECTIVE: To better explore the relationship between parameters of glycemic control of T2DM in RRT, we studied 23 patients on hemodialysis (HD), 22 on peritoneal dialysis (PD), and compared them with 24 T2DM patients with normal renal function (NRF). MATERIALS AND METHODS: We performed, on four consecutive days, 10 assessments of capillary blood glucose [4 fasting, 2 pre- and 4 postprandial (post-G) and average (AG)], random glycemia, and HbA1c in all patients. RESULTS: Preprandial blood glucose was greater in patients on RRT compared with NRF. Correlations between AG and HbA1c were 0.76 for HD, 0.66 for PD, and 0.82 for NRF. The regression lines between AG and HbA1c were similar for patients on HD and with NFR, but they were displaced upward for PD. CONCLUSION: Similar HbA1c values in PD patients may correspond to greater levels of AG than in HD or NRF patients.
Estabelecimento de um plano de manutenção baseado em análises quantitativas no contexto da MCC em um cenário de produção JIT
Authors: Mendes Angélica Alebrant , Ribeiro José Luis Duarte
Published: September 2013

Este artigo apresenta um método para desenvolver análises quantitativas que orientem a revisão ou elaboração de um plano de manutenção de equipamentos em um cenário de produção just in time. O método proposto contempla: i) Identificar os conjuntos que influenciam a confiabilidade; ii) Levantar taxas de falhas; iii) Classificar os conjuntos quanto ao efeito de suas falhas; iv) Levantar parâmetros de demanda da linha; v) Identificar as distribuições de probabilidade da demanda da linha e dos tempos de bom funcionamento e tempos de reparo dos conjuntos; vi) Simular a produção/manutenção utilizando o método de Monte Carlo; vii) Realizar uma análise de sensibilidade a eventuais variações na demanda, MTBF e MTTR; e viii) Estabelecer a estratégia de manutenção e intervalos entre manutenções preventivas. A aplicação do método é ilustrada através de um estudo real realizado em uma linha de rotulagem e enchimento de galões de uma empresa do setor de tintas e corantes. A aplicação do método permitiu identificar com clareza os conjuntos e subconjuntos críticos frente ao cenário produtivo em questão.
Desenvolvimento e validação de uma escala de afetos positivos e negativos
Authors: Zanon Cristian , Bastianello Micheline Roat , Pacico Juliana Cerentini , Hutz Claudio Simon
Published: September 2013

O objetivo deste estudo foi construir e buscar evidências de validade para uma escala de afetos positivos e negativos (EA). Participaram 853 universitários do sul do Brasil (57% mulheres) com idade média de 21 anos (DP=3). Os resultados da análise de eixos principais mostraram uma solução bifatorial. O primeiro fator apresentou eigenvalue de 5,1, explicando 25,6% da variância total, e o segundo fator, com eigenvalue de 2,6, explicou 12,8% da variância total. A consistência interna da escala foi de 0,83 para afetos positivos (AP) e 0,77 para os negativos (AN). Foram realizadas correlações entre AP e AN para verificar evidências de validade convergente da EA com a PANAS. Observaram-se altas correlações de AP (r=0,73) e AN (r=0,74). AP apresentou correlações positivas com satisfação de vida, esperança, otimismo e autoestima, enquanto AN apresentou correlações negativas com essas variáveis. Conclui-se que a EA apresentou evidências de validade de construto e propriedades psicométricas adequadas.
Contribuições da Análise Fatorial Confirmatória Multigrupo (AFCMG) na avaliação de invariância de instrumentos psicométricos
Authors: Damásio Bruno Figueiredo
Published: September 2013

A Análise Fatorial Confirmatória Multigrupo (AFCMG) é uma técnica da modelagem de equações estruturais que avalia em que medida a configuração e os parâmetros de determinado instrumento psicométrico são invariantes (equivalentes) para diferentes grupos. Tal técnica tem se apresentado como um importante recurso no desenvolvimento, no uso, na avaliação e no refinamento de instrumentos psicométricos. Entretanto, no Brasil há enorme escassez de publicações sobre o tema. Assim, o presente estudo discute a AFCMG, apresentando suas potencialidades. Ao longo do artigo três grandes tópicos são abordados: os diferentes modelos a serem testados, a invariância completa versus a invariância parcial, e os métodos de avaliação de invariância dos modelos. Espera-se que esta leitura auxilie pesquisadores na compreensão, na interpretação e no uso da AFCMG.
Marcas no corpo, cansaço e experiência: nuances do envelhecer como professor de Educação Física
Authors: Lüdorf Sílvia Maria Agatti , Ortega Francisco Javier Guerrero
Published: September 2013

Este trabalho objetivou compreender e interpretar os significados que os professores de Educação Física atribuem ao corpo e envelhecimento, e investigar como tais representações influenciariam sua prática profissional. Participaram da investigação, de natureza qualitativa, 43 professores de escolas e academias de ginástica com cerca de trinta anos de formação. Os dados foram tratados mediante análise de conteúdo. O envelhecimento do professor propicia maturidade, experiência e confiança no trabalho, mas o corpo físico parece desprender-se do sujeito, repercutindo em sentimentos contraditórios relacionados ao envelhecimento. Nas academias, há certo ajuste ao contexto da visibilidade, pois são valorizadas as potencialidades e as marcas de saúde impressas no corpo. Já o desgaste e o cansaço são particularmente sentidos pelos professores atuantes em escola.
O silêncio dos inocentes: por um estudo narrativo da prática médica
Authors: Carelli Fabiana Buitor , Pompilio Carlos Eduardo
Published: September 2013

Embora absolutamente pertinente, a relação entre texto e medicina ainda é pouco pesquisada no meio acadêmico brasileiro. Não obstante, é fato que toda prática médica é permeada de narrativas, quer sejam as dos pacientes, que contam aos médicos as histórias de suas doenças, quer as dos médicos, que recontam essas histórias de acordo com modelos científicos aprendidos e com sua experiência clínica. Inspirado na Narrative-Based Medicine, campo teórico já consolidado no meio anglófono, e em algumas teorias provenientes dos Estudos Literários e das Ciências Sociais, este artigo busca discutir, introdutoriamente, algumas possibilidades para a consolidação de um estudo interdisciplinar das narrativas relacionadas à área médica no âmbito acadêmico brasileiro.
O impacto da pobreza no Ideb: um estudo multinível
Authors: Duarte Natalia de Souza ,   Secretaria de Educação do Distrito Federal,  Brazil,   Centro Universitário do Distrito Federal,  Brazil
Published: September 2013

Objetiva investigar, por meio de análise de regressão multinível, o impacto da pobreza no Índice de Desenvolvimento da Educação Básica (Ideb) das escolas. Para tanto, foi considerado o percentual de beneficiários do Programa Bolsa Família nas instituições de ensino com Ideb 2009. Na composição do modelo matemático, foi utilizada a metodologia multinível e inseridas variáveis do nível da escola e do município. Depois de considerar o efeito das variáveis dos diferentes níveis, verificou-se um impacto de -0,42 no modelo 1 e -0,29 no modelo 2. Isso significa que a presença de alunos em situação de pobreza tem efeito negativo bastante considerável no Ideb da escola; custo-aluno, população e região também interferem nessa relação. Espera-se que os resultados deste estudo apoiem o enfrentamento da meritocracia e a defesa de mais recursos para a educação.
O desempenho de estudantes no Enem 2010 em diferentes regiões brasileiras
Authors: Viggiano Esdras ,   Universidade de São Paulo, Mattos Cristiano ,   Universidade Federal do Triângulo Mineiro, Brazil,   Universidade de São Paulo, Brazil
Published: September 2013

Ao resgatar o caráter diagnóstico do Exame Nacional do Ensino Médio (Enem), investiga e compara o desempenho dos estudantes de cada uma das regiões geográficas do Brasil no exame realizado em 2010 para cada uma das áreas do conhecimento que o integram: Redação; Ciências da Natureza; Linguagens e Códigos; Ciências Humanas; e Matemática. Para a investigação, utilizamos os microdados disponibilizados pelo Ministério da Educação os quais foram analisados por meio da estatística descritiva. Os resultados apontam três grupos de desempenho: superior (Sul e Sudeste); médio (Centro-Oeste); e inferior (Norte e Nordeste). Todas as áreas apresentaram baixo desempenho - inferiores a 58% -, entretanto, na prova de Redação verificou-se o oposto em relação à de Linguagens quando comparadas as regiões.
Remuneração inicial dos professores das redes municipais do Paraná no contexto municipal
Authors: Subirá Juliana Aparecida Alves ,   Universidade Federal do Paraná,  Brazil
Published: September 2013

Nas últimas décadas, a questão da remuneração dos professores tem perpassado as políticas educacionais como expressão da valorização docente, constituindo, este artigo, o resultado do cotejamento das políticas educacionais nacionais, inclusive as municipais, pertinentes à remuneração dos professores. O período proposto para a investigação abrange os anos de 1996 a 2010. Por meio dos dados coletados, construiu-se um panorama da configuração da remuneração inicial dos professores do magistério público no Paraná, no contexto socioeconômico dos municípios selecionados, constatando-se discrepâncias na remuneração inicial praticada entre diversos municípios e semelhanças entre os municípios mais ricos, que possuem as maiores remunerações iniciais.
Formação continuada para professores da educação básica nos anos iniciais: ações voltadas para municípios com baixo Ideb
Authors: Costa-Hübes Terezinha da Conceição ,   Universidade Estadual do Oeste do Paraná,  Brazil,   Instituto Nacional de Estudos e Pesquisas Educacionais Anísio Teixeira,  Brazil
Published: September 2013

Apresenta resultados parciais de uma pesquisa vinculada à Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes), ao Instituto Nacional de Estudos e Pesquisas Educacionais Anísio Teixeira (Inep) e ao programa Observatório da Educação. Nosso objetivo é discorrer sobre atividades desenvolvidas do ano de 2011 até meados de 2012, na área de Língua Portuguesa, voltadas para os eixos leitura e produção escrita de texto, refletindo sobre as ações de formação continuada. Trata-se, portanto, de uma pesquisa calcada nos pressupostos teóricos da Linguística Aplicada, por voltar-se para o estudo da língua em sua ação efetiva. Os resultados parciais, confirmados pelo Índice de Desenvolvimento da Educação Básica (Ideb) de 2011, já apontam para avanços significativos na qualidade do ensino nos municípios envolvidos, principalmente no que diz respeito à disciplina de Língua Portuguesa.
Projeto pedagógico do curso de licenciatura em Ciências da UFPR Litoral: desafios e possibilidades para uma formação emancipatória
Authors: Silva Lenir Maristela ,   Universidade Federal do Paraná,  Brazil, Brizolla Francéli , Silva Luiz Everson da ,   Universidade Federal do Pampa,  Brazil,   Universidade Federal do Paraná,  Brazil
Published: September 2013

A crítica aos currículos fragmentados em disciplinas tem sido recorrente em inúmeras publicações nacionais. A dificuldade para a implantação de currículos não disciplinares nos cursos de ensino superior em universidades estabelecidas há décadas esbarra, principalmente, nas relações de poder dentro das universidades. O setor Litoral da Universidade Federal do Paraná (UFPR) faz parte do plano de expansão das instituições brasileiras de ensino superior e, assim, marcou seu início com o desafio de fazer diferente, ou seja, atuar com currículos não disciplinares. Nesse sentido, apresentamos detalhadamente o projeto pedagógico do curso de licenciatura em Ciências construído ao longo dos quatro anos de sua existência.
Os Ambientes de Aprendizagem possibilitando transformações no ensinar e no aprender
Authors: Gautério Vanda Leci Bueno ,   Universidade Federal do Rio Grande, Rodrigues Sheyla Costa ,   Coordenação de Aperfeiçoamento de Pessoal de Nível Superior,  Brazil,   Universidade Federal do Rio Grande,  Brazil
Published: September 2013

Estudo sobre como se ensina e se aprende, a partir do olhar dos estudantes dos anos finais do ensino fundamental, em uma escola da rede pública que articula seu fazer pedagógico em Ambientes de Aprendizagem. Relatos escritos foram coletados no decorrer das atividades e analisados utilizando-se o Discurso do Sujeito Coletivo (DSC) como metodologia. Os discursos evidenciam mudanças no ensinar e no aprender, em decorrência da transformação das salas de aula convencionais em Ambientes de Aprendizagem, mostram ainda que os estudantes percebem as aulas mais dinâmicas, pois agora têm liberdade para levantar, dialogar com os colegas e usar o material didático disponível, e destacam que a ação docente está mais acolhedora e que os alunos acreditam em uma grande mudança na educação.
Reflexões a respeito do uso da modelagem matemática em aulas nos anos iniciais do ensino fundamental
Authors: Tortola Emerson ,   Universidade Estadual de Londrina,  Brazil, Almeida Lourdes Maria Werle de ,   Universidade Estadual de Londrina,  Brazil
Published: September 2013

As discussões sobre o uso da modelagem matemática têm revelado que atividades desse tipo podem atender a interesses e necessidades da formação matemática dos estudantes na contemporaneidade - no que diz respeito à avaliação da aprendizagem dos alunos mediante essas atividades, entretanto, ainda há inquietações. Compartilhando destas, apresentamos resultados decorrentes de uma pesquisa em que alunos que participaram do desenvolvimento de atividades de modelagem matemática foram submetidos, um ano após esse desenvolvimento, à resolução de questões em que os conteúdos que emergiram daquelas atividades estavam envolvidos. A pesquisa está associada ao Programa Observatório da Educação e apresenta reflexões acerca do desempenho de estudantes do 5º ano do ensino fundamental ao realizarem questões vinculadas à Prova Brasil, instrumento utilizado pelo Instituto Nacional de Estudos e Pesquisas Educacionais Anísio Teixeira (Inep) como base de cálculo para obtenção do Índice de Desenvolvimento da Educação Básica (Ideb). Os resultados apontam para o potencial da modelagem matemática em abordar conteúdos curriculares, propostos pelos Parâmetros Curriculares Nacionais (PCN), e sinalizam a aprendizagem dos estudantes, em particular, nos anos iniciais do ensino fundamental.
Mitigating impacts of water shortage on Egyptian agriculture: a catchment scale analysis
Authors: Gohar Abdelaziz A. , Ward Frank A.
Published: September 2013

The impacts of water shortages on Egypt's agriculture continues to receive widespread attention. Several mitigation schemes have been proposed to reduce the potential economic impact of supply reductions of the Nile's waters into Egypt. This paper examines the economic consequences for the Egyptian agricultural economy of application of limited water markets to mitigate the impacts of potential water supply shortages. We address this aim by assembling detailed data on farm budgets, hydrology, institutions and culture in order to develop an integrated catchment framework for analyzing Egypt's use of the Nile. The results of our policy analysis illustrate that a limited form of water trading is one institutionally flexible measure that can mitigate the impacts of water shortages. When water supplies flowing into Egypt are reduced by 10 and 20% per year, adopting limited water trading reduces national farm income losses by 32 and 33% per year, respectively, compared to income losses borne without trading. So water trading grows in importance as a measure to sustain farm income in the face of more severe water shortages. Our findings provide insight for Egyptian policymakers to enable examination of options to mitigate the economic impacts of water supply shortages resulting from drought, climate change, or renegotiated arrangements for sharing the Nile's waters.
Learning and Developing as a University Teacher: Narratives of Early Career Academics in Estonia
Authors: Remmik Marvi , Karm Mari , Lepp Liina
Published: September 2013

In recent years the higher education context in Estonia, as in most European countries, has changed a lot. All changes have an impact on university teachers' practice and their work organisation, and are presenting new challenges. The current research aims at developing an understanding of Estonian early career academics' professional identity by using their teaching narratives. The research is based on the consideration that narratives have previously yielded good results in investigating professional identity and related underlying concepts. This article is based on semi-structured interviews with 41 early career academics specialising in various disciplinary fields in higher education. On the basis of the analysis, the authors found that academics constructed their life as a whole while retelling their stories and made links between their previous life and being an academic. The findings from the research reveal that early career academics' experiences of teaching and their professional identity as teachers differ depending on individual agency, prior learning, work experience, context, and informal relations. The research also showed that narratives helped the interviewees to view and reflect upon their experiences and professional identity as university teachers and plan their future perspectives in the university.
Autoethnographic Journeys in Learning and Teaching in Higher Education
Authors: Trahar Sheila
Published: September 2013

In this article, the author describes how the methodological approach of autoethnography enabled her to interrogate the philosophical underpinnings of the learning and teaching practices that she espoused as a university academic. This critical questioning was provoked through her interactions with postgraduate students from a range of contexts and academic traditions in a School of Education in a university in the United Kingdom. Through personal reflections and conversations with her ‘selves' on her teaching and on her supervisory relationships with doctoral researchers, the author strives to show how she reduced her reliance on familiar ideas and changed the shape of her teaching through questioning her ‘selves’, beliefs and values. The value of autoethnography in enabling this critical exploration when working in an international European higher education context is highlighted. An aim is to encourage greater use of this methodological approach in European higher education research to enable greater sensitivity to our diverse constituencies.
Integrated Education in Conflicted Societies: Is There a Need for New Theoretical Language?
Authors: Zembylas Michalinos , Bekerman Zvi
Published: September 2013

This article takes on the issue of ‘integrated education’ in conflicted societies and engages in a deeper analysis of its dominant theoretical concepts, approaches, and implications. This analysis suggests that the theoretical language that drives current approaches of integrated education may unintentionally be complicit to the project of hegemony and status quo, thus preventing social transformation towards shared and just societies. As the article discusses, present research on integrated education in conflicted societies — not only in the European context, but also around the world — suggests that the main theoretical traditions which seem to justify integration in the education sphere are those of social cohesion, contact hypothesis, and acculturation theory. The article analyses these traditions theoretically and looks at some of their empirical results in conflicted societies, highlighting the problematic implications of the language that essentialises group identities. In the process to find an alternative theoretical language, the ideas of Judith Butler and Julia Kristeva are used to reconsider integrated education along the lines of a renewed theorisation of the notion of ‘critical multiculturalism’.
Observations on the Herpetofauna of the Builavânturariţa Massif (Southern Carpathians, Romania )
Authors: Iftime Alexandru , Iftime Oana
Published: September 2013

The results of herpetological investigations in the Buila-Vânturariţa massif (Southern Carpathians, Romania) and its surrounding areas are reported here. 19 amphibian and reptile species were identified (Salamandra salamandra, Triturus cristatus, Ichthyosaura alpestris, Lissotriton vulgaris, Bombina variegata, Bufo bufo, B. viridis, Hyla arborea, Rana temporaria, R. dalmatina, Pelophylax ridibundus, P. lessonae, Emys orbicularis, Lacerta agilis, L. viridis, Podarcis muralis, Zootoca vivipara, Zamenis longissimus, Natrix natrix) and are presented together with distribution and ecological data.
Nano hydroxyapatite–polysulfone coating on Ti-6Al-4V substrate by electrospinning
Authors: Santhosh S. , Prabu S. Balasivanandha
Published: September 2013

Titanium alloys that are used as implant materials generally fail due to the occurrence of significant localized corrosion by interactions with corrosive body fluid. Implants also undergo loosening and detachment from the bone due to its poor biocompatibility. In this study, nano hydroxyapatite synthesized via a wet chemical method, using calcium oxide obtained from sea shells, was used to prepare a composite coating with polysulfone and was electrospun on to Ti-6Al-4V alloy. The controlling parameters of electrospinning were varied to study the characteristics of the coating followed by bioactivity studies, to ensure the biocompatibility of the coated material.
Microstructures and corrosion resistance of three typical superlight Mg–Li alloys
Authors: Qu Zhikun , Wu Ruizhi , Zhang Jinghuai , Zhang Milin
Published: September 2013

Three typical superlight Mg–Li alloys (Mg-5Li-3Al-2Zn, Mg-8Li-3Al-2Zn and Mg-14Li-3Al-2Zn) with the matrixes of alfa(Mg), alfa(Mg) + beta(Li) and beta(Li), respectively, are prepared. The microstructures of the alloys are characterized using optical microscopy and X-ray diffraction. The corrosion resistant properties of the alloys are characterized by means of hydrogen evolution, weight loss and potentiodynamic polarization. The alloys are also oxidized at elevated temperature. The microstructure and corrosion resistant property of the alloys after oxidation are also characterized.
Oral Health Status of Pregnant Women attended the Mothers and Children Welfare Center (MCWC) in Bangladesh
Authors: Rahman Md Mahafuzur , Hassan Md Riasat , Islam Md Ziaul , Ahmad Mohammad Sayeed , Alam Md Monirul , Islam KM Mohidul
Published: September 2013

Aim: Oral health problem is one of the major health problems during pregnancy in both developing and developed countries. This cross-sectional study was carried out to assess the oral health status of the pregnant women attended some selected mothers and children welfare centers (MCWCs) in Bangladesh. Methods: Data was collected by face-to-face interview and clinical examination with the help of a structured questionnaire and check list. Results: Half (50.0%) of the pregnant women was of 15 to 20 years old and their mean age was 22.28±4.22 years. Thirty eight percent (38.2%) of the women had primary education and 78.4% did not visit any dentist. Majority (93.1%) used tooth brush before breakfast and most (84.4%) of them had no information about oral hygiene care. Regarding oral health status, 87.3% had caries affected teeth and 94.1% had gingivitis. Presence of gingivitis and calculus were higher among the elder women (21-35 years) than the younger group (15-20 years) which was 92.2% among the housewives. Gingivitis was significantly higher among the women in low income group (95.7%) than the other income groups (X2 = 5.80, p<0.05). Conclusion: The study findings recommended for provision of essential dental health services to the pregnant women for prevention and control of various dental health problems during pregnancy. DOI: http://dx.doi.org/10.3329/cdcj.v10i2.16312 City Dent. Coll. J Volume-10, Number-2, July-2013
Reduction of Masticatory Neurons in the Tooth-extracted Mice: A Year-long Study
Authors: Rashid Mohammed Enamur , Akhter Khaleda , Maeda Norihiko
Published: September 2013

Background: It has been reported that the number of masticatory motor and sensory neurons were seriously diminished and the masseter muscles were severely atrophied in the genetically mutant osteopetrotic (op/op) mouse with no eruption of teeth and less-developed periodontal ligaments. The present study was designed to observe whether the sensory input from the periodontal mechanoreceptive afferents be involved in the development and maintenance of the masticatory system. Methods: A case-control study was carried out with 2 groups of male ICR mice. Unilateral extraction of upper and lower molars was carried out in the case group on day 20 after birth. For assessing effects of tooth loss on the masticatory neurons, both mice groups were sacrificed on days 30, 60, 90, 120, 180 and 360 after birth and the trigeminal mesencephalic neurons (Me5) and trigeminal ganglion (TG) were traced and counted on both sides of the central nervous System (CNS). Results: In case group, severe degeneration of the ipsilateral inferior alveolar nerve (IAN) was observed on as early as day 40 after birth and there was significant decrease in the number of labeled Me5 and TG neurons between 60th and 360th postnatal days on the tooth-extracted side. Labeled primary afferent terminals were also severely diminished in the trigeminal sensory nuclear complex (TSNC) on the tooth-extracted side. Conclusion: Present study suggests that the decrease in the sensory input due to the tooth loss causes the disorder of the development and maintenance of the masticatory system even in the normal animal. DOI: http://dx.doi.org/10.3329/cdcj.v10i2.16315 City Dent. Coll. J Volume-10, Number-2, July-2013
Antimicrobial Efficacy of Endomethasone and Sealapex Sealers against Specific Endodontic Pathogens
Authors: Chowdhury Rownakara , Alam Md Shamsul , Rubby Md Golam , Rabbi Golam , Azad SM Salahuddin Al , Khatun Mst Amina , Islam Tania , Sultana Nihar
Published: September 2013

Background: Antimicrobial efficacy is one of the desired properties of root canal sealer to eliminate the residual microorganisms from complex root canal system unaffected by chemomechanical preparation and intracanal medication. The aim of the study is to compare the antimicrobial effects of two different sealers, i.e. zinc oxide based Endomethasone and calcium hydroxide based Sealapex against E. faecalis, S. aureus and C. albicans which are considered most resistant microorganisms in the oral cavity. Methods: Agar diffusion method was used in this study. The sealers were prepared according to manufacturers instruction and placed in prepared wells 36 agar plates inoculated with E. faecalis, S. aureus and C. albicans. All plates were incubated for 5 days at 370C. The zone of inhibition of each sealer was measured after 24 hours, 48 hours and 5 days interval in order to evaluate the antimicrobial efficacy in different time duration. Statistical analysis was performed by ANOVA, independent sample t test and paired t test as applicable. P value <0.05 was considered as statistically significant. Results: Endomethasone produced largest zone of inhibition at all-time interval than that of Sealapex against all tested microorganisms. However, the zone of inhibition of Endomethasone reduced significantly after 48 hours. The antimicrobial efficacy of Sealapex gradually increased at all times interval. Conclusion: The antimicrobial efficacy of Endomethasone against E. faecalis, S. aureus and C. albicans is higher than that of Sealapex. DOI: http://dx.doi.org/10.3329/cdcj.v10i2.16317 City Dent. Coll. J Volume-10, Number-2, July-2013
Attitude on Oral Hygiene among the School going Children in Selected Schools at Dhaka city
Authors: Ahmed Shamim , Solaiman Faisal , Islam Md Rakibul , Akhter Syeda Mahmuda , Nizami Mohammed Zahedul Islam , Khatun Mst Amina
Published: September 2013

Aims: The study was carried out among 1200 students of selected schools at Dhaka city to observe their attitude on oral hygiene through a pre-tested semi-structured questionnaire. Methods: The descriptive type of cross-sectional study was carried out among 1200 students of class IV-IX (aged 10-15 years) in the selected schools of Dhaka city from December 2011 to March 2012 to observe their attitude on oral hygiene through a pre-tested semi-structured questionnaire. Results: This study revealed that 92.5% of respondents understood the importance of taking care of oral cavity. Seventy seven percent (76.7%) of respondents agreed that regular brushing would prevent tooth decay. Of all, 69.2% respondents brushed their teeth regularly where, 69.2% brushed once a day, 27.5% brushed twice and only 3.3% brushed more than twice in a day. Ninety three percent (92.5%) used toothbrush and 83.3% used tooth paste for brushing their teeth. Among the respondents, 67.5% knew that sweet food caused harm to teeth and 50.0% thought that soft drinks would have the same effects on teeth. Sixty nine (69.2%) percent of respondents reported that they went to dentist on requirement basis and only 8.3% of respondents regularly went to dentist for checkup. An association was found between mothers occupation and regular brushing prevents tooth decay (p=0.04). Conclusion: The study suggested that the students would be the appropriate target group to receive the first organized intervention leading towards improving the oral health status and reducing prevalence of oral diseases through increasing their attitude. DOI: http://dx.doi.org/10.3329/cdcj.v10i2.16346 City Dent. Coll. J Voume-10, Number-2, July-2013
Rheumatoid Arthritis: Pattern and Prevalence of Extra-Articular Manifestations - A Prospective Study
Authors: Haidar MS , Razzak MA , Yasin MM
Published: September 2013

DOI: http://dx.doi.org/10.3329/jafmc.v8i2.16353 JAFMC Vol.8(2) 2012 pp.39-46
Prevalence of Metabolic Syndrome in Army Personnel Residing in Bogra Cantonment
Authors: Kabir MA , Hossain MR , Haque MF , Fakir MAH , Rahimgir M , Momtaz S
Published: September 2013

DOI: http://dx.doi.org/10.3329/jafmc.v8i2.16354 JAFMC Vol.8(2) 2012 pp.47-51
Atherosclerotic Changes in Coronary Arteries in the Deceased Soldiers Died of Non Cardiac Causes
Authors: Islam DMJ , Alam SMM , Hossain MS , Ahmad M , Islam MH
Published: September 2013

DOI: http://dx.doi.org/10.3329/jafmc.v8i2.16355 JAFMC Vol.8(2) 2012 pp.52-57
Total Proctocolectomy with Ileoanal Endorectal Pullthrough in Familial Adenomatous Polyposis
Authors: Khan SUD Elias , Sarkar BK , Rahman S , Jafran SS
Published: September 2013

DOI: http://dx.doi.org/10.3329/jafmc.v8i2.16361 JAFMC Vol.8(2) 2012 pp.87-90
Polymorphisms in Fatty Acid Desaturase (FADS) Gene Cluster: Effects on Glycemic Controls Following an Omega-3 Polyunsaturated Fatty Acids (PUFA) Supplementation
Authors: Cormier Hubert , Rudkowska Iwona , Thifault Elisabeth , Lemieux Simone , Couture Patrick , Vohl Marie-Claude
Published: September 2013

Changes in desaturase activity are associated with insulin sensitivity and may be associated with type 2 diabetes mellitus (T2DM). Polymorphisms (SNPs) in the fatty acid desaturase (FADS) gene cluster have been associated with the homeostasis model assessment of insulin sensitivity (HOMA-IS) and serum fatty acid composition. Objective: To investigate whether common genetic variations in the FADS gene cluster influence fasting glucose (FG) and fasting insulin (FI) responses following a 6-week n-3 polyunsaturated fatty acids (PUFA) supplementation. Methods: 210 subjects completed a 2-week run-in period followed by a 6-week supplementation with 5 g/d of fish oil (providing 1.9 g–2.2 g of EPA + 1.1 g of DHA). Genotyping of 18 SNPs of the FADS gene cluster covering 90% of all common genetic variations (minor allele frequency ≥ 0.03) was performed. Results: Carriers of the minor allele for rs482548 (FADS2) had increased plasma FG levels after the n-3 PUFA supplementation in a model adjusted for FG levels at baseline, age, sex, and BMI. A significant genotype*supplementation interaction effect on FG levels was observed for rs482548 (p = 0.008). For FI levels, a genotype effect was observed with one SNP (rs174456). For HOMA-IS, several genotype*supplementation interaction effects were observed for rs7394871, rs174602, rs174570, rs7482316 and rs482548 (p = 0.03, p = 0.01, p = 0.03, p = 0.05 and p = 0.07; respectively). Conclusion: Results suggest that SNPs in the FADS gene cluster may modulate plasma FG, FI and HOMA-IS levels in response to n-3 PUFA supplementation.
High-Level Overproduction of Thermobifida Enzyme in Streptomyces lividans Using a Novel Expression Vector
Authors: Li Jun-Xia , Zhao Long-Mei , Wu Ru-Juan , Zheng Zhao-Jun , Zhang Ri-Jun
Published: September 2013

In this study, we constructed a novel Streptomyces-E.coli shuttle vector pZRJ362 combining the xylose isomerase promoter and amylase terminator. A gene encoding the endoglucanase Cel6A in Thermobifida fusca was amplified by PCR, cloned into Streptomyces lividans host strain using the novel expression vector and Pichia pastoris GS115 host strain using the vector pPICZα-C, respectively. Afterwards, the expression pattern and the maximum expression level were comparatively studied in both expression systems. The maximum enzyme activity of Cel6A-(His)6 secreted in S. lividans supernatant after 84-h of cultivation amounted to 5.56 U/mL, which was dramatically higher than that secreted in P. pastoris about 1.4 U/mL after 96-h of cultivation. The maximum expression level of Cel6A-(His)6 in S. lividans supernatant reached up to 173 mg/L after 84-h of cultivation. The endoglucanase activity staining SDS-PAGE showed that there were some minor proteins in S. lividans supernatant which may be the Cel6A derivant by proteolytic degradation, while there was no proteolytic product detected in supernatant of P. pastoris.
Linking Land Cover Data and Crop Yields for Mapping and Assessment of Pollination Services in Europe
Authors: Zulian Grazia , Maes Joachim , Paracchini Maria
Published: September 2013

Pollination is a key ecosystem service as many crops but in particular, fruits and vegetables are partially dependent on pollinating insects to produce food for human consumption. Here we assessed how pollination services are delivered at the European scale. We used this assessment to estimate the relative contribution of wild pollinators to crop production. We developed an index of relative pollination potential, which is defined as the relative potential or relative capacity of ecosystems to support crop pollination. The model for relative pollination potential is based on the assumption that different habitats, but in particular forest edges, grasslands rich in flowers and riparian areas, offer suitable sites for wild pollinator insects. Using data of the foraging range of wild bees with short flight distances, we linked relative pollination potential to regional statistics of crop production. At aggregated EU level, the absence of insect pollination would result in a reduction of between 25% and 32% of the total production of crops which are partially dependent on insect pollination, depending on the data source used for the assessment. This production deficit decreases to 2.5% if only the relative pollination potential of a single guild of pollinators is considered. A strength of our approach is the spatially-explicit link between land cover based relative pollination potential and crop yield which enables a general assessment of the benefits that are derived from pollination services in Europe while providing insight where pollination gaps in the landscape occur.
Diterpenylquinone Hybrids: Synthesis and Assessment of Gastroprotective Mechanisms of Action in Human Cells
Authors: Theoduloz Cristina , Bravo Ivanna , Pertino Mariano , Schmeda-Hirschmann Guillermo
Published: September 2013

A modern approach in the search for new bioactive molecules is the synthesis of novel chemical entities combining molecules of different biosynthetic origin presenting biological effects as single compounds. Gastroprotective compounds from South American medicinal plants, namely quinones and diterpenes, were used as building blocks to obtain hybrid diterpenylquinones. Starting from the labdane diterpene junicedric acid and two isomers, as well as from three quinones, including lapachol, 18 hybrid molecules were synthesized. Six of them are described for the first time. The potential gastroprotective mechanisms of action of the compounds were assessed in dose-response experiments using human gastric epithelial cells (AGS) and human lung fibroblasts (MRC-5). The following studies were carried out: stimulation of cell proliferation, cytoprotection against sodium taurocholate (NaT)-induced damage, synthesis of PGE2 and total reduced sulfhydryl (GSH) content. The antioxidant capacity of the compounds was determined on the inhibition of the lipoperoxidation in human erythrocyte membranes. Hybrid compounds presented activities different from those shown by the starting compounds, supporting the potential of this approach in the search for new bioactive molecules. The effects might be modulated by selective modification in the terpene or quinone moieties of the new molecules. Structure-activity relationships are discussed.
Ultraviolet Fluorescence LiDAR (UFL) as a Measurement Tool for Water Quality Parameters in Turbid Lake Conditions
Authors: Palmer Stephanie , Pelevin Vadim , Goncharenko Igor , Kovács Attila , Zlinszky András , Présing Mátyás , Horváth Hajnalka , Nicolás-Perea Virginia , Balzter Heiko , Tóth Viktor
Published: September 2013

Despite longstanding contributions to oceanography, similar use of fluorescence light detection and ranging (LiDAR) in lake settings is not routine. The potential for ship-mounted, multispectral Ultraviolet Fluorescence LiDAR (UFL) to provide rapid, high-resolution data in variably turbid and productive lake conditions are investigated here through a series of laboratory tank and field measurements carried out on Lake Balaton, Hungary. UFL data, calibrated empirically to a set of coinciding conventionally-analyzed samples, provide simultaneous estimates of three important parameters-chlorophyll a(chla), total suspended matter (TSM) and colored dissolved organic matter (CDOM). Successful UFL retrievals from both laboratory and field measurements were achieved for chla (0.01–378 mg∙m−3; R = 0.83–0.92), TSM (0.1–130 g∙m−3; R = 0.90–0.96) and CDOM (0.003–0.125 aCDOM(440); R = 0.80–0.97). Fluorescence emission at 685 nm is shown through tank measurements to display robust but distinct relationships with chla concentration for the two cultured algae species investigated (cyanobacteria, Cylindrospermopsis raciborskii, and chlorophyta, Scenedesmus armatus). The ratio between fluorescence emissions measured at 650 nm, related to the phycocyanin fluorescence maximum, to that at 685 nm is demonstrated to effectively distinguish these two species. Validation through both laboratory measurements and field measurements confirmed that site specific calibration is necessary. This study presents the first known assessment and application of ship-mounted fluorescence LiDAR in freshwater lake conditions and demonstrates the use of UFL in measuring important water quality parameters despite the more complicated hydro-optic conditions of inland waters.
Strontium-Doped Hematite as a Possible Humidity Sensing Material for Soil Water Content Determination
Authors: Tulliani Jean-Marc , Baroni Chiara , Zavattaro Laura , Grignani Carlo
Published: September 2013

The aim of this work is to study the sensing behavior of Sr-doped hematite for soil water content measurement. The material was prepared by solid state reaction from commercial hematite and strontium carbonate heat treated at 900 °C. X-Ray diffraction, scanning electron microscopy and mercury intrusion porosimetry were used for microstructural characterization of the synthesized powder. Sensors were then prepared by uniaxially pressing and by screen-printing, on an alumina substrate, the prepared powder and subsequent firing in the 800–1,000 °C range. These sensors were first tested in a laboratory apparatus under humid air and then in an homogenized soil and finally in field. The results evidenced that the screen printed film was able to give a response for a soil matric potential from about 570 kPa, that is to say well below the wilting point in the used soil.
Exploring individual, social and organisational effects on Web 2.0-based workplace learning: a research agenda for a systematic approach
Authors: Zhao Fang , Kemp Linzi
Published: September 2013

Web 2.0-based workplace learning is defined in this article as informal learning that takes place in the workplace through connections and collaborations mediated by Web 2.0 technology. Web 2.0-based workplace learning has the potential to enhance organisational learning and development. However, little systematic research has been published that explores how individual, social and organisational factors may influence Web 2.0-based workplace learning. This study aims to address this knowledge gap. Drawing on a selective review of the theories and research on social exchange, social capital, communities of practice and organisational support, we have developed a testable theoretical model for further empirical study.Keywords: Web 2.0; workplace learning; social exchange; social capital; communities of practice; organisational learning and development(Published: 11 September 2013)Citation: Research in Learning Technology 2013, 21: 19089 - http://dx.doi.org/10.3402/rlt.v21i0.19089