3,635 research outputs found

    Gelation of n3p3[nh(ch2)3si(oet)3]6-n [x]n x = nh(ch2)3si(oet)3, nch3(ch2)3cn and oc6h4(ch2)cn, n = 0 or 3 at the liquid/air/interface

    Get PDF
    Indexación: ScieloThe compounds N3P3[NH(CH2)3Si(OEt)3]6 (1), N3P3[NH(CH2)3Si(OEt)3]3[NCH3(CH2)3CN]3 (2) and N3P3[NH(CH2)3Si(OEt)3]3 [HOC6H4(CH2)CN]3 (3) undergo slow gelation at the interface oil/air at low temperatures to give perfect gels G1, G2 and G3 respective ly. TEM analysis reveals nanoparticles of silica with mean size of about 10 nm. Pyrolysis under air at 800 °C of these gels affords a mixture of mainly Si5(PO4)6O, SiP2O7 and SiO2. Gelation and pyrolysis products were characterized by IR, solid-state NMR, TEM, SEM-EDAX microscopy and X-ray diffraction. The sol-gel process in the interface liquid /air is discussed in comparison with the usual sol-gel solution process.http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072010000300031&nrm=is

    Sol-gel incorporation of organometallic compounds into silica: useful precursors to metallic nanostructured materials

    Get PDF
    Indexación: Web of Science; ScieloLa inclusión del MLN organometálica = HOC 6 H 4 CH 2 CN • Mo (CO) 5 (6) en sílice amorfa con los precursores TEOS gelificante y N 3 P 3 {NH [CH 2 ] 3 Si [OEt] 3 } 6 permitirse los geles (MLN) ( SiO 2 ) n . Los nanocompuestos híbridos inorgánicos-orgánicos se piroliza bajo aire a 800 º C para dar óxidos nanoestructurados metálicos y / o pirofosfatos de metal (fosfatos) incluidos en las matrices de sílice. La morfología de los nanocompuestos monolíticas exhiben una fuerte dependencia con el precursor del gel utilizado es principalmente laminar para aquellos preparados utilizando N 3 P 3 {NH [CH 2 ] 3 Si [OEt] 3 } como gelificante. Las imágenes de TEM muestran la forma y tamaño diferentes, tales como nanopartículas circulares, nanocables y aglomerados en algunos casos con tamaños de 20 nm para las nanoestructuras circulares y de diámetro aproximadamente 25 nm para los nanocables.Inclusion of the organometallic MLn = [HOC5H4N•Cp2TiCl][PF6] (1), HOC5H4N-W(CO)5 (2), HOC5H4N•Mo(CO)5 (3), [HOC6H4CH2CN•Cp2TiCl][PF6] (4), HOC6H4CH2CN•W(CO)5 (5) and HOC6H4CH2CN•Mo(CO)5 (6) into amorphous silica using the gelator precursor TEOS and N3P3{NH[CH2]3Si[OEt]3}6 afford the gels (MLn)(SiO2)n. The inorganic-organic hybrid nanocomposites were pyrolyzed under air at 800°C to give nanostructured metal oxides and/or metal pyrophosphates (phosphates) included in the silica matrices. The morphology of the monolithic nanocomposites exhibited a strong dependence on the gel precursor used being mainly laminar for those prepared using N3P3{NH[CH2]3Si[OEt]3} as gelator. TEM images show different shape and size such as circular nanoparticles, nanocables and agglomerates in some cases with sizes of 20 nm for the circular nanostructures, and diameter about 25 nm for the nanocables.http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072012000200021&nrm=is

    Microgravity’s effect on the skeletal muscle: muscular adaptations and therapeutic intervention

    Get PDF
    Introdução – O incremento do tempo de exposição à microgravidade origina um descondicionamento músculo-esquelético que precisa de ser prevenido através do treino. Objetivos – Identificar os padrões destas alterações e descrever os programas de treino em microgravidade e estratégias pós-exposição. Método – A pesquisa da revisão da literatura foi conduzida através da MEDLINE/PubMed e PEDro com as seguintes palavras--chave: “spaceflight rehabilitation”, “spaceflight muscle”, “microgravity muscle” e “bed rest muscle”, seguida de uma seleção dos artigos. Resultados – Os estudos encontrados apresentam uma resposta músculo-tendinosa diferencial sendo que o treino protege total ou parcialmente estas estruturas. Conclusão – O treino de resistance de intensidade elevada e baixas repetições associado a exercícios específicos é o mais adequado para responder ao descondicionamento. - ABSTRACT - Introduction – The increased microgravity exposition time raised the need for training programs to avoid muscle and tendinous deconditioning. Objectives – To identify the deconditioning patterns and to identify and describe the training programs used for its prevention during and after microgravity exposure. Methods – This literature review is based on a search conducted via MEDLINE/PubMed and PEDro using the following search words: “spaceflight rehabilitation”, “spaceflight muscle”, “microgravity muscle” and “bed rest muscle”. The search was followed by an article selection. Results – The studies reveal a differential exposure phenomenon for which the training programs reviewed are partly effective. Conclusion – According to the literature the high intensity low volume resistance programs with specific exercises are more appropriate to address the deconditioning problem

    Physiotherapy intervention in Angola: what physicians think?

    Get PDF
    Background: Physical therapy is an essential part of health systems. Physiotherapists can practice independent of other health professionals and also in the context of programs and interdisciplinary projects of habilitation/rehabilitation with the aim of giving function and quality of life in individuals with loss movement. There are guidelines for physiotherapists based on international standards issued by the World Confederation of Physical Therapy. (WCPT), what must be followed by physiotherapists globally. There are several health problems in Angola such as Malaria, stroke and traffic accidents that require physical therapy intervention in their rehabilitation process. Since doctors are professionals first contact in Angola responsible for referral of patients for physical therapy, it is pertinent to understand their awareness of the importance of the intervention of physiotherapists. Purpose: This study sought to investigate the perception of medical professionals in orthopedics, neurology and general practitioner of some hospital institutions in Luanda, Porto Amboim, Sumbe in Angola on the intervention of physiotherapists. Methods: The method used was quantitative descriptive and exploratory. The evaluation was conducted through a questionnaire response you close to 19 items, and the first part of the characterization of the sample (5 Items) and the second part consisting for items the advice of the doctors on the intervention of the physiotherapist in Angola (14 Items). The sample consisted of 38 doctors from orthopedists, neurologists and general practitioner in Luanda, Porto Amboim and Sumbe in Angola. For the analysis of the data was used IBM software Statistical Package for Social Sciences (SPSS statistics 20.0for Windows®). Results: The 38 individuals in the study 22 were male and 16 were female, Luanda is the city with the highest frequency of individuals who participated in the study, most are a general practitioner and worked in private clinics. Most believe that physiotherapists have a specific body of knowledge and can support their interventions. Most participants said that doctors have little knowledge of the professional physiotherapist role and not always refer their patients to physical therapy. The results of the study showed that neurologists and orthopedists have a perception of the greater importance of physiotherapy intervention. Conclusion(s): The doctors think it is important the intervention of the physiotherapist, and the three specialties orthopedics was considered as the one that needs more of the physiotherapist performance. Implications: This work can serve as an indicator of the view that doctors in Angola have of physiotherapists, can also serve to raise awareness of policies related to the integration of the physiotherapist in the multidisciplinary team in Angola.info:eu-repo/semantics/publishedVersio

    Gene expression rearrangements denoting changes in the biological state

    Full text link
    In many situations, the gene expression signature is a unique marker of the biological state. We study the modification of the gene expression distribution function when the biological state of a system experiences a change. This change may be the result of a selective pressure, as in the Long Term Evolution Experiment with E. Coli populations, or the progression to Alzheimer disease in aged brains, or the progression from a normal tissue to the cancer state. The first two cases seem to belong to a class of transitions, where the initial and final states are relatively close to each other, and the distribution function for the differential expressions is short ranged, with a tail of only a few dozens of strongly varying genes. In the latter case, cancer, the initial and final states are far apart and separated by a low-fitness barrier. The distribution function shows a very heavy tail, with thousands of silenced and over-expressed genes. We characterize the biological states by means of their principal component representations, and the expression distribution functions by their maximal and minimal differential expression values and the exponents of the Pareto laws describing the tails

    Psychometric characteristics of the instruments used to assess quality of life in multiple sclerosis: a literature review

    Get PDF
    A esclerose múltipla (EM) é a doença crónica neurológica que mais afeta adultos jovens; em 80% dos casos, a doença progride para situações de níveis variados de incapacidade, o que torna necessário avaliar a qualidade de vida (QV) desses indivíduos. O objetivo desta revisão foi localizar estudos que avaliam a QV em indivíduos com EM, identificando os instrumentos utilizados e suas características psicométricas. Foram consultadas as bases Psycinfo, Psycarticles, Psycbooks, Psychology & Behavioral Science Collection, EJS E-Journal, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Medline, e Academic Search Complete, utilizando os descritores 'multiple sclerosis' e 'quality of life', para localizar artigos publicados no período 1997-2007. Foram selecionados 1.376 artigos e, após a leitura dos resumos, excluídos os referentes a instrumentos que não tinham boas características psicométricas e/ou eram pouco referenciados. Foram encontrados 461 artigos, dos quais 267 usaram instrumentos genéricos e 194 específicos para a EM. Dos 7 instrumentos (2 genéricos, 5 específicos) com boas características psicométricas utilizados pelos estudos consultados, o mais usado é o SF-36 (em 237 estudos). Todos os instrumentos têm validade verificada e apresentam grau elevado de confiabilidade, podendo ser utilizados para avaliação da qualidade de vida de pacientes com EM tanto em pesquisa quanto na clínica. ABSTRACT - Multiple sclerosis (MS) is the chronic neurological disease that most affects young adults; 80% of patients experience a transition towards persistent disability, hence the need to assess their quality of life (QoL). The aim of the study was to review studies that assess QoL in patients with multiple sclerosis, inquiring on the instruments used and their psychometric features. Articles published from 1997 through 2007 were searched for by means of key words 'multiple sclerosis' and 'quality of life' in databases Psycinfo, Psycarticles, Psycbooks, Psychology & Behavioral Science Collection, EJS E-Journal, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Medline, and Academic Search Complete. From the 1,376 studies found, after abstract reading those that reported on instruments with poor psychometric properties and/or were little referred were excluded. A total of 461 articles were selected, of which 267 reported using generic instruments and 194, MS-specific ones. Among the 7 instruments reported by the studies as having good psychometric characteristics (2 generic, five MS-specific), the most used is the SF-36 (by 237 studies). All instruments have shown adequate psychometric properties and a high degree of reliability, hence may be used to assess QoL in subjects with multiple sclerosis both in clinic and research

    Relationship between optimism and functional autonomy in individuals with multiple sclerosis

    Get PDF
    Objetivo: O presente estudo tem como objetivo verificar a relação existente entre autonomia funcional e otimismo. Método: Os participantes são 280 indivíduos portadores de esclerose múltipla (EM) diagnosticada há mais de um ano em que a maioria são mulheres, com nível elevado de escolaridade, maioritariamente casados, e a trabalhar em regime de tempo integral. A funcionalidade foi avaliada com a Escala de Impacto de Participação e Autonomia – IPA, e o otimismo com o Life Orientation Test – Revised (LOT-R). A recolha de dados realizou-se em unidades de saúde de Lisboa e cumpriu as regras conforme a Declaração de Helsínquia. Conclusão: Os resultados mostram que existem valores de correlação estatisticamente significativos, mas moderados entre as dimensões da LOT-R e IPA, sugerindo que o otimismo é um fator importante para a autonomia funcional dos indivíduos portadores de EM. ABSTRACT - Aim: The present study aims at identifying the relationship between optimism and functional autonomy in individuals with Multiple Sclerosis (MS). Method: The participants are 280 individuals diagnosed with MS for more than one year; the majority are women, with high levels of education, mostly married and employed on full time. To access functionality we used the Impact on Participation and Autonomy Scale – IPA, and to assess optimism the Life Orientation Test - Revised (LOT-R). Data was collected in Lisbon health settings. Data collection follows the rules of the Helsinki Declaration. Conclusion: Results show that correlations between the two main variables are statistically significant, but moderate, suggesting that the perception of optimism is an important factor for functional autonomy in individuals with MS

    Análise psicométrica da escala de impacto na autonomia e participação, em pessoas com esclerose múltipla

    Get PDF
    A avaliação da Autonomia e funcionalidade das pessoas com esclerose múltipla é fundamental para a compreensão das limitações e necessidades destas pessoas. O presente estudo tem como objectivo estudar as propriedades psicométricas da Escala de Impacto Autonomia e Participação em doentes com esclerose múltipla. Participaram neste estudo 280 indivíduos com diagnóstico de esclerose múltipla, 71,4% mulheres com idade média de 39,23 anos. Procedeu-se à análise factorial exploratória, consistência interna, teste-reteste, validade convergente e discriminante. Os resultados demonstram valores psicométricos apropriados para a versão de língua portuguesa semelhantes às versões de língua alemã e de língua inglesa. Concluímos que esta escala tem boas condições psicométricas para avaliar a autonomia funcional em indivíduos com esclerose múltipla. ABSTRACT: Assessment of Autonomy and participation of patients with multiple sclerosis is essential to understand the limitations and necessities of these patients. The present study aims to examine the psychometric proprieties of the Impact on Participation and Autonomy Questionnaire (IPA) in patient with multiple sclerosis. Participants are 280 patients with a diagnostic of multiple sclerosis, 71.4% females, mean age of 39.23 years. We inspect metric properties namely, validity, construt validity and convergent and discriminant validity, and reliability, internal consistency and test-retest. The results show that IPA is a reliable and valid instrument for assessment autonomy and participation in Portuguese language, with similar sensibility than the Germany and English version. In conclusion these instruments have psychometric conditions for assessment the functional autonomy of people with multiple sclerosis
    • …
    corecore