bluuebunny/crossref_metadata_2025 huggingface dataset:
Consumo alimentar de crianças em municípios de baixo índice de desenvolvimento humano no Nordeste do Brasil
Authors: Costa Emilia Chagas , Silva Silvia Patrícia de Oliveira , Lucena José Rodolfo Mendonça de , Batista Filho Malaquias , Lira Pedro Israel Cabral de , Ribeiro Marisilda de Almeida , Osório Mônica Maria
Published: September 2011

OBJETIVO: Este trabalho tem como objetivo analisar o consumo alimentar de crianças em Gameleira, na Zona da Mata Meridional de Pernambuco, e em São João do Tigre, no Semi-Árido da Paraíba, municípios do Nordeste do Brasil. MÉTODOS: Trata-se de estudo transversal envolvendo crianças menores de dois anos, das quais 238 em Gameleira, e 207 em São João do Tigre. O consumo alimentar foi registrado utilizando o método recordatório de 24 horas. Os nutrientes foram analisados utilizando as Dietary Referency Intakes. RESULTADOS: O consumo médio de energia e da maioria dos nutrientes esteve acima das ingestões de referência, em todas as faixas etárias e em ambos os municípios. A maioria dos valores de prevalência de risco de inadequação dos nutrientes foram elevados, principalmente de ferro e zinco, nas crianças entre 7 e 11 meses. O município de São João do Tigre apresentou prevalência de risco, com inadequação em todas as faixas etárias e nutrientes analisados, com exceção da proteína e do ferro na faixa etária entre 12 e 23 meses, embora sem diferença estatisticamente significante. CONCLUSÃO: A situação nutricional da população estudada ainda preocupa devido às acentuadas prevalências de risco de inadequação dos nutrientes. Portanto, é necessária a elaboração de estratégias que reforcem e promovam a segurança alimentar e nutricional para essas populações, a fim de evitar o risco de instalação de distúrbios nutricionais.
Aleitamento materno e práticas alimentares de crianças menores de seis meses em Alfenas, Minas Gerais
Authors: Arantes Cássia Irene Spinelli , Oliveira Maísa Muniz , Vieira Thaís Cristina Rodrigues , Beijo Luiz Alberto , Gradim Clícia Valim Côrtes , Goyatá Sueli Leiko Takamatsu
Published: September 2011

OBJETIVO: Determinar a prevalência da amamentação e avaliar o consumo de outros alimentos em crianças menores de seis meses em Alfenas, Estado de Minas Gerais. MÉTODOS: Trata-se de estudo epidemiológico transversal, realizado por meio de inquérito domiciliar com uma amostra de 126 crianças nascidas em 2008. Os dados foram obtidos a partir de formulário com o recordatório de 24 horas da alimentação da criança e outras questões. Na análise dos dados, foi utilizado o Programa Epi Info, versão 6.04. Foi determinada a prevalência das diferentes categorias de amamentação (amamentação exclusiva, amamentação predominante, amamentação complementada e amamentação) segundo faixas etárias. O Teste de Fischer e o Teste qui-quadrado foram calculados na associação de variáveis com o aleitamento materno. RESULTADOS: A prevalência da amamentação exclusiva em crianças menores de seis meses foi de 37,3%. A introdução de alimentos semissólidos ocorreu acentuadamente a partir do quinto mês de vida. No sexto mês, 50,7% das crianças encontravam-se em amamentação complementada. As crianças menores de seis meses não amamentadas, comparadas com as amamentadas, apresentaram prevalências significativamente maiores quanto ao consumo de água, frutas e comida da família. Não foram encontradas diferenças significativas entre a amamentação exclusiva até o sexto mês e as variáveis maternas estudadas. CONCLUSÃO: Apesar de vários resultados deste estudo apresentarem-se superiores aos de outros municípios, a prevalência do aleitamento materno em Alfenas ainda está distante da recomendação de que crianças recebam exclusivamente leite materno até os seis meses de idade.
Qualidade nutricional das refeições servidas em uma unidade de alimentação e nutrição de uma indústria da região metropolitana de São Paulo
Authors: Gorgulho Bartira Mendes , Lipi Marisa , Marchioni Dirce Maria Lobo
Published: September 2011

OBJETIVO: Avaliar a qualidade nutricional das refeições servidas em uma Unidade de Alimentação e Nutrição de uma fábrica da região metropolitana da cidade de São Paulo. MÉTODOS: Dentre os cardápios praticados no período de um ano (242 dias) na unidade mencionada, foram selecionados 30% por sorteio sistemático, e avaliados utilizando-se o Índice de Qualidade da Refeição, com base nas recomendações da Organização Mundial da Saúde e do Ministério da Saúde brasileiro. Esse índice compõe-se de cinco itens que variam entre zero e 20 pontos cada um: adequação na oferta de hortaliças e frutas; oferta de carboidratos; oferta de gordura total; oferta de gordura saturada e variabilidade do cardápio. No período analisado, foram servidas 367 preparações, agrupadas em 30 categorias, segundo composição e forma de preparo. A correlação de Spearman foi utilizada para investigar a correlação do índice com os nutrientes da refeição. As análises foram realizadas no pacote estatístico STATA, considerando-se o nível de significância de 5%. RESULTADOS: O valor médio do Índice de Qualidade da Refeição foi de 64,60 (DP=21,18) pontos, sendo 44% das refeições classificadas como "refeição que necessita de melhora" e apenas 25% como "adequadas". Além do arroz e do feijão, servidos diariamente, as preparações mais frequentes foram: legumes e frutas (30%), massas e cremes (12%), frituras (9%) e sobremesas com creme (8%). Encontrou-se correlação positiva entre o Índice de Qualidade da Refeição e a vitamina C (r=0,32). CONCLUSÃO: Apesar da presença constante de frutas, legumes e verduras, há a necessidade de adequar a oferta das preparações às recomendações para uma alimentação saudável, que efetivamente colaborem na promoção da saúde.
Peso, estatura e comprimento em crianças e adolescentes com síndrome de Down: análise comparativa de indicadores antropométricos de obesidade
Authors: Martin Juan Eduardo Samur-San , Mendes Roberto Teixeira , Hessel Gabriel
Published: September 2011

A obesidade é considerada uma epidemia, que acomete também crianças e adolescentes com síndrome de Down. Contudo, como não há um parâmetro consensual para diagnosticar obesidade nessa população, o objetivo deste trabalho foi realizar uma revisão crítica de artigos que estudam índices antropométricos, para avaliação do estado nutricional de crianças e adolescentes com essa síndrome. O levantamento dos artigos foi realizado nas bases de dados PubMed, MedlLine, Lilacs e SciELO, dando-se importância aos parâmetros antropométricos e sua relação com a obesidade. De 83 artigos iniciais, foram selecionados 11 para análise crítica. Nos Estados Unidos, estabeleceram uma curva de normalidade para peso e estatura de crianças e adolescentes com síndrome de Down e, quando compararam os seus valores com as curvas do National Center for Health Statistics, observaram que houve um padrão menor de crescimento em estatura. Em estudos europeus, observou-se o mesmo fato. No Brasil, Mustacchi desenvolveu índices de peso/idade e estatura/idade e observou deficit importante de estatura, quando comparou estatura/idade com as curvas do National Center for Health Statistics e com as curvas de Cronk et al. Em CONCLUSÃO:, os dados antropométricos disponíveis em curvas pôndero-estaturais são considerados relativos a uma determinada população e revelam suas características específicas, porque expressam a influência dos fatores ambientais e determinantes genéticos. Portanto, há necessidade de se definir curvas de padrão de referência para crianças e adolescentes com síndrome de Down em diferentes faixas etárias, regiões e etnias, para se diagnosticar corretamente seu estado nutricional.
Desempenho de adultos não-letrados em avaliação das habilidades em consciência fonológica
Authors: Mota Helena Bolli , Romero Marta de Vargas , Kaminski Tassiana Isabel , Vidor-Souza Débora , Berticelli Aline
Published: September 2011

OBJETIVO: verificar o desempenho das habilidades em consciência fonológica em adultos não-letrados e compará-lo com o de adultos letrados. MÉTODO: 31 adultos, ambos os sexos, divididos em não-letrados e letrados, submetidos à Prova de Consciência Fonológica. RESULTDOS: o desempenho dos adultos não-letrados foi insatisfatório e inferior ao dos letrados; os dois grupos apresentaram desempenho inferior em tarefas fonêmicas; em apenas dois subtestes não foi encontrada diferença estatisticamente significante entre os grupos. CONCLUSÃO: o desempenho inferior dos adultos não-letrados, especialmente nas tarefas fonêmicas, pode decorrer do fator escolaridade, pois não dominam o código alfabético.
Patient perceptions about anesthesia and anesthesiologists before and after surgical procedures
Authors: Leite Fernanda , Silva Leopoldo Muniz da , Biancolin Sckarlet Ernandes , Dias Adriano , Castiglia Yara Marcondes Machado
Published: September 2011

CONTEXT AND OBJECTIVE: Anesthesiologist-patient relationships are established preoperatively and intraoperatively. These are opportunities for providing correct information about anesthesia/anesthesiologists, thereby improving outcomes. The aim here was to evaluate patients' perceptions about anesthesiologists before anesthesia and to identify whether the anesthetic care would change such perceptions. DESIGN AND SETTING: Prospective cross-sectional study using data obtained in 2007-2008, at a tertiary university hospital. METHODS: 518 patients aged 16 years or over were interviewed before and after anesthesia exposure. A questionnaire was used to determine patient characteristics and perceptions of anesthesia/anesthesiologists. RESULTS: The patients were 16-89 years of age and 59.8% had attended elementary school. 79.1% said that anesthesiologists were specialized physicians. Anesthesiologists' roles were associated with loss of consciousness (35.5% pre-anesthesia; 43.5% post-anesthesia), pain relief (29.7% pre-anesthesia, 31.7% post-anesthesia), vital sign monitoring (17.6% pre-anesthesia, 35% post-anesthesia; P < 0.05); and drug administration (10.8% pre-anesthesia, 43.9% post-anesthesia; P < 0.05). The level of confidence in the physician was rated high (82.2% and 89.8% pre- and post-anesthesia, respectively; P < 0.05) or intermediate (5.8% and 6.6% pre- and post-anesthesia, respectively; P < 0.05). The care provided by anesthesiologists was classified as: elucidating (52.8%), encouraging (52.6%), neutral (10.2%) and careless (0.8%). CONCLUSION: Patients' perceptions of anesthesiologists' roles were fairly good, but improvements in this relationship still need to be pursued, to achieve better outcomes. Anesthetic care was important in providing information, confidence and reassurance among patients, regarding their perceptions. Anesthesiologists should not miss opportunities to provide excellent professional care for patients, thereby improving anesthesia outcomes and their image.
Comparative evaluation of digital mammography and film mammography: systematic review and meta-analysis
Authors: Iared Wagner , Shigueoka David Carlos , Torloni Maria Regina , Velloni Fernanda Garozzo , Ajzen Sérgio Aron , Atallah Álvaro Nagib , Valente Orsine
Published: September 2011

CONTEXT AND OBJECTIVE: Mammography is the best method for breast-cancer screening and is capable of reducing mortality rates. Studies that have assessed the clinical impact of mammography have been carried out using film mammography. Digital mammography has been proposed as a substitute for film mammography given the benefits inherent to digital technology. The aim of this study was to compare the performance of digital and film mammography. DESIGN: Systematic review and meta-analysis. METHOD: The Medline, Scopus, Embase and Lilacs databases were searched looking for paired studies, cohorts and randomized controlled trials published up to 2009 that compared the performance of digital and film mammography, with regard to cancer detection, recall rates and tumor characteristics. The reference lists of included studies were checked for any relevant citations. RESULTS: A total of 11 studies involving 190,322 digital and 638,348 film mammography images were included. The cancer detection rates were significantly higher for digital mammography than for film mammography (risk relative, RR = 1.17; 95% confidence interval, CI = 1.06-1.29; I² = 19%). The advantage of digital mammography seemed greatest among patients between 50 and 60 years of age. There were no significant differences between the two methods regarding patient recall rates or the characteristics of the tumors detected. CONCLUSION: The cancer detection rates using digital mammography are slightly higher than the rates using film mammography. There are no significant differences in recall rates between film and digital mammography. The characteristics of the tumors are similar in patients undergoing the two methods.
Brief motivational interview and educational brochure in emergency room settings for adolescents and young adults with alcohol related problems: a randomized single blind clinical trial
Authors: Segatto Maria Luiza , Andreoni Solange , Souza e Silva Rebeca de , Diehl Alessandra , Pinsky Ilana
Published: September 2011

OBJECTIVE: To evaluate the effectiveness of brief motivational interviewing and an educational brochure when delivered in emergency room to reduce alcohol abuse and related problems among adolescents and young adults. METHOD: a randomized single blind clinical trial with a 3 month follow-up was carried out at three emergency rooms from October 2004 to November 2005; subjects assessed were 16-25 years old treated for alcohol related events up to 6 hours after consumption. Socio-demographic data, quantity, frequency and negative consequences of alcohol consumption, motivation to change habits and future risk preception were evaluated. Statistical analysis was performed on subjects who completed follow up (completers). ANCOVA model was used to analyze the difference between the intervention groups with statistical significance level α = 5% and Confidence Interval (CI) 95%. RESULTS: 186 subjects formed the initial sample, being n = 175 included and randomized to educational brochure group (n = 88) or motivational interviewing group (n = 87). Follow-up assessment was performed in 85.2% sample. No significant difference between groups was observed. However, significant reductions (p < 0.01) in related problems and alcohol abuse were found in both groups. CONCLUSION: In this sample a reduction of alcohol use and related problems was observed. Preliminary data indicates that controlled clinical trials with motivational interviewing, educational brochure and nonintervention should be of future interest among Brazilian adolescent population.
The relationship between perceived social support and severity of body dysmorphic disorder symptoms: the role of gender
Authors: Marques Luana , Weingarden Hilary M. , LeBlanc Nicole J. , Siev Jedidiah , Wilhelm Sabine
Published: September 2011

OBJECTIVE: Whether social support is associated with severity of body dysmorphic symptoms is unknown. To address this gap in the literature, the present study aims to examine the association between three domains of perceived social support (i.e., family, friends, and significant others) and severity of body dysmorphic disorder symptoms. METHOD: Participants (N = 400) with symptoms consistent with diagnosis of body dysmorphic disorder completed measures of symptomatology and social support via the internet. RESULTS: More perceived social support from friends and significant others was associated with less severe body dysmorphic disorder symptoms for males, and more perceived social support from family and friends was associated with less severe body dysmorphic disorder symptoms among females. Additionally, gender moderated the association between perceived social support from significant others and symptom severity, such that perceived social support from a significant other was significantly negatively associated with body dysmorphic symptom severity in males, but not females. CONCLUSION: The present study implicates social support as an important area of future body dysmorphic disorder research.
Instruction in developmental psychiatry: preliminary findings at the undergraduate level in Brazil
Authors: Moraes Erika Neves de Souza , Scivoletto Sandra , Fossaluza Vitor , Vieira Joaquim Edson , Miguel Euripedes Constantino , Alvarenga Pedro Gomes de
Published: September 2011

BACKGROUND: Although knowledge on developmental psychiatry is fundamental for the early recognition, treatment, and prevention of mental disorders, this subject has not been incorporated into the medical curriculum or psychiatric practice in Brazil. OBJECTIVE: To evaluate the effect of a short course on developmental psychiatry for undergraduate students and to expand education policies concerning developmental psychiatry in Brazil. METHODS: Before and after attending an extracurricular 12-hour, 4-day course on the fundamentals of developmental psychiatry, undergraduate health sciences students were tested regarding their knowledge of the subject. The pre-test/post-test included 12 randomly selected multiple-choice questions designed to evaluate knowledge related to developmental psychiatry and was administered together with a questionnaire designed to evaluate students' attitudes. To compare performances between groups, nonparametric analyses of ordinal categorical data were employed. RESULTS: The final sample comprised 43 students. The mean post-test score was significantly higher than the mean pre-test score (65.0% vs 39.9%; p < 0.0001). We found that strongly positive attitudes correlated with better performance. The 3rd and 4th year medical students performed better than the 1st and 2nd year medical students and the non-medical students. Sex differences favoring males were also observed. CONCLUSION: Our findings encourage additional educational policies related to developmental psychiatry which may result in direct clinical implications.
Clean-up of Oil Pollution at Sea
Authors: Morris P. R.
Published: September 2011

The available methods for the clean-up of oil (and certain chemical) spills at sea are considered and recent developments in two fields namely, dispersant application and oil recovery, covered in detail.

The application of dispersants is shown to be restricted by the viscosity of the oil on the water which increases rapidly due to oil in water emulsion formation. Samples of oil emulsion recovered of the water can show poor response to dispersants when the viscosity increases to about 7,500-10,000 cP depending on the dispersant used and the nature of the crude oil. Differences in dispersant performance can be shown by use of a laboratory test.

The development and limitations of recovery systems are considered with reference to the Springsweep system. Mention is made to netting systems for use with oils which are semi solid on the surface of the water.
Medical Operations in the Offshore Theatre
Authors: Dick J. S.
Published: September 2011

This paper presents a review of the work undertaken over the last fifteen years at Great Yarmouth, Norfolk, in providing medical support for offshore personnel. This now includes very comprehensive onshore facilities for full medical examinations, including X-rays, audiograms, vision screening, tests of lung capacity, etc. The seven G.P.s who operate this organisation in conjunction with a 16,000 patient N.H.S. Health Centre are all diving doctors however, and are contracted to give specialised medical cover to divers not only in the North Sea, but in Norwegian, Dutch, Middle Eastern, West African and even Far Eastern waters. This necessitates a very sophisticated telephone, telex, offshore radio and car radio system in order to provide 24-hour cover. Regular inspection trips are also made offshore by helicopter. Specialist residential courses in advanced first aid and diving medicine are also run for divers and offshore sick bay attendants.
An Efficient Fully Implicit Simulator
Authors: Cheshire Ian M. , Appleyard John R. , Banks Derek , Crozier Robert J. , Holmes Jonathan A.
Published: September 2011

This paper describes PORES, an efficient general purpose implicit three-phase three-dimensional black oil reservoir simulator. Efficiency is achieved by solving the coupled equations using a new sequential method which automatically ensures material balance. A new iterative method for the solution of the linear equations is described. This method also conserves material and uses a truncated conjugate gradient technique to accelerate convergence. Simultaneous and direct solution options are also provided. PORES contains an extensive well model which is numerically stable, meets production targets precisely, and apportions flows accurately to individual layers of the reservoir model. Other practical features include a numerical aquifer model, flexible pseudo function facilities, and a two-point upstream option for the control of numerical dispersion. Two examples are presented to illustrate the use of the fully-implicit sequential method.
The Use of Higher Order Finite Difference Methods in Reservoir Simulation
Authors: Young Mark S. , Casinader Prins C. , Wilson David C.
Published: September 2011

A nine point finite difference scheme is proposed which extends previous work and allows for the use of an irregular grid and non-isotropic permeabilities. Comparison of results with that achieved by conventional simulators illustrate the degree of improvement that can be achieved. It is shown, however, that while the higher order scheme considerably reduces grid orientation effects it cannot, on its own, eliminate the problem of numerical dispersion. Various devices are combined with the nine point scheme to control numerical dispersion and a simple technique is demonstrated to be highly effective. It is also demonstrated that use of numerical dispersion control implies the use of vectorised relative permeabilities. The techniques described thus allow the engineer to concentrate on reservoir description as the effects of grid orientation and numerical dispersion on the simulator have been significantly reduced.
The effect of ball milling and wet blending on the creep behaviour of a particle reinforced 2124 Al-alloy
Authors: Requena Guillermo , Bauer Bernd , Degischer Hans Peter , Lieblich Marcela
Published: September 2011

The creep behaviour of an AW2124 Al-alloy unreinforced and reinforced with 25 vol.% of SiC particles of different sizes is investigated. The materials were produced via powder metallurgy using two powder blending techniques: ball milling and wet blending. The SiC particles are fractured during ball milling resulting in 2 – 3 vol.% of sub-μm SiC particles. The SiC particles in the wet blended composites are in the μm-range. The creep behaviour of the matrices and the ball milled composites is characterized by a low-stress and a high-stress region. In the low-stress region the creep deformation is governed by viscous drag of dislocations, while climb of dislocations dominates in the high-stress region. The high creep resistance exhibited by the ball milled composites is mainly due to the presence of oxide dispersoids introduced during blending of the powders.
Fabrication of dielectric thin films by sputtering deposition at different pressures with (Ba0.3Sr0.7)(Zn1/3Nb2/3)O3 ceramic as target
Authors: Shi Feng
Published: September 2011

Dielectric ceramic thin films have been fabricated by radio frequency magnetron sputtering on SiO2 (110) substrates with different sputtering pressures and the as-sputtered samples were subsequently annealed in an O2 atmosphere. The microstructure and morphology of the thin films were investigated, particularly as a function of pressures. The thin films deposited at 0.25 Pa are polycrystalline with high-quality crystals and are made up of dense rod-like structures. The main phases are Ba0.5Sr0.5Nb2O6 and Ba0.27Sr0.75Nb2O5.78, which are different from the target because of the volatilization of ZnO. The results indicate that appropriate sputtering pressure contributes to the improvement of the crystal quality and the grain growth of the dielectric ceramic thin films.
Evolution of transformation plasticity during bainitic transformation
Authors: Lambers Hans-Gerd , Tschumak Sergej , Maier Hans Jürgen , Canadinc Demircan
Published: September 2011

The influences of prior austenitization treatment and the state of applied stresses on the evolution of transformation plasticity strains during isothermal bainitic phase transformation and the resulting microstructures were examined. The key finding is that, upon pre-straining, the amount of transformation plasticity strain under superimposed elastic stresses is dictated by both the prior austenite grain size and the (0.01 % offset) yield strength of the supercooled austenite. Furthermore, the superimposition of internal stresses present due to pre-straining and externally applied stresses results in transformation plasticity strains similar to those obtained when a permanent stress equivalent to the 0.01 % offset yield strength of the supercooled austenite is applied. Another important result is that lower transformation plasticity strains were observed when decreasing the austenite grain size, which is accompanied by an increase in grain boundary area per volume, hindering the growth of preferred variants. Overall, the results clearly lay out the influence of austenite grain size and the particular 0.01 % offset yield strength of the supercooled austenite in limiting the transformation plasticity strains, which has to be incorporated into current models involving bainitic phase transformations.
Phase equilibria in the Fe–Mg–Si system
Authors: Löffler Falk , Sauthoff Gerhard , Palm Martin
Published: September 2011

Phase equilibria in the Fe–Mg–Si system have been determined experimentally at 800 and 1 000 °C using alloys of fixed composition and diffusion couples. Besides the phases that occur in the binary systems no additional phases were observed. However, Fe5Si3, the only phase that shows a marked solid solubility for the third component, is stabilised by the addition of Mg to lower temperatures than in the binary Fe–Si system, thus forming a ternary composition at 800 °C. A complete isothermal section has been set up for 800 °C, while only selected phase equilibria were determined at 1 000 °C.
Analysing SANS data to determine magnetisation reversal processes in composite perpendicular magnetic recording media using TEM images
Authors: Lister S. J. , Kohlbrecher J. , Venkataramana V. , Thomson T. , Takano K. , Lee S. L.
Published: September 2011

Perpendicular magnetic recording media based on CoCrPt – SiOx thin-films have been studied with polarised small angle neutron scattering (SANSPOL) to probe the local (sub-10 nm) granular structure and its magnetisation distribution. SANSPOL is sensitive to the direction of the magnetisation vector in the grains over a size range of 1 – 100 nm. This allows the grain size dependent magnetic reversal process to be probed in the recording layer. SANSPOL data can be analysed both using numerical models and through comparison with the granular structure determined using transmission electron microscopy. In this paper we compare these two methods in detail and demonstrate that both approaches arrive at very similar conclusions.
Materials issues of the SINQ high-power spallation target
Authors: Wagner Werner , Vontobel Peter , Dai Yong
Published: September 2011

The Swiss spallation neutron source SINQ operated at the Paul Scherrer Institut is driven by PSI's 590 MeV proton accelerator at a beam power of 0.8 MW, as such being the most powerful (CW) spallation source worldwide. The core element of such a facility is the neutron production target. Since the commissioning in 1997, PSI has always fostered combined efforts in the development of the spallation target, including dedicated materials research for high dose radiation environments. The overall goal was to achieve optimized neutron production, combined with sufficient robustness, thermo-mechanical stability and radiation resistance to withstand the severe loads of high-dose irradiation and frequent thermal cycling over an acceptable lifetime. The target itself has been improved in several steps by searching for the optimal materials and geometries. In parallel, numerous experiments have been conducted in the targets of SINQ for studying radiation damage effects induced by high energy protons and spallation neutrons.
TEM study of irradiation induced copper precipitation in boron alloyed EUROFER97 steel
Authors: Klimenkov M. , Vladimirov P. , Möslang A. , Materna-Morris E. , Schneider H.-C.
Published: September 2011

Specimens of the European reference 9Cr-WTaV steel EUROFER 97 alloyed with ∼0.1 wt.% 10B and 0.5 wt.% Cu were neutron irradiated up to 16 dpa at 300 and 400 °C to study an interplay between helium generated by nuclear reaction on 10B and copper precipitates on microstructure and mechanical properties. Before irradiation 2 – 3 nm copper clusters often trapped on grain or lath boundaries were observed. It was shown that after irradiation copper segregates either in the bulk material by forming Cu-clusters which are in many cases attached to helium bubbles or it further precipitates at lath and grain boundaries. The size of both copper clusters and helium bubbles increases with radiation temperature.
Coarsening kinetics of Cu-rich precipitates in a concentrated multicomponent Fe–Cu based steel
Authors: Kolli R. Prakash , Seidman David N.
Published: September 2011

The coarsening kinetics of Cu-rich precipitates in a concentrated multicomponent Fe–Cu based steel, containing 1.12 at.% Cu, aged at 550 °C or at 550 °C plus 2 h at 200 °C is investigated. The temporal evolution of the precipitates, heterophase interfaces, and a-Fe matrix compositions and precipitate morphology are presented. Coarsening time exponents are determined for the mean radius, , and number density, Nv(t), and compared to the Lifshitz – Slyzov – Wagner model for coarsening, modified for concentrated multicomponent alloys by Umantsev – Olson. The experimental results indicate that  and Nv(t) are in reasonable agreement with Umantsev – Olson model behavior. Additionally, we compare the results to earlier investigations of similar concentrated multicomponent steels containing 1.82 at.% Cu and 1.17 at.% Cu, aged at 500 °C.
Surface tension and viscosity of NiAl catalytic precursor alloys from microgravity experiments
Authors: Wunderlich Rainer K. , Fecht Hans-Jörg
Published: September 2011

The surface tension and the viscosity of the catalytic precursor alloys Ni-68.5 at.% Al, Ni-75 at.% Al and Ni-75 at.% Al-1.5 at.%. Cr were measured over a temperature range of about 400 K using the oscillating drop technique in an electromagnetic levitation device under reduced gravity conditions. The experiments were performed on board parabolic flights and on a TEXUS sounding rocket flight. At the liquidus temperatures of 1 604 K and 1398 K the viscosities of Ni-68.5 at.% Al and Ni-75 at.% Al were obtained as ν(Tliq) = 4.31 mPa · s and ν(Tliq) = 4.53 mPa · s, respectively. In the investigated temperature range the viscosity exhibited a linear temperature dependence. The surface tension as a function of temperature can be represented as ω(T) = 1.01 N m−1 – 2.8 · 10−4 (T – 1 603 K) N m−1 and ω(T) = 0.92 N m−1 – 1.40 · 10−4 (T – 1 398 K) N m−1 for Ni-68.5 at.% Al and Ni-75 at.% Al, respectively. Comparison of the experimental viscosities with predictions from different semi-empirical models showed that the latter underestimate the experimental values by between 25 and 40%.
Effect of Mechanical Milling on the Thermal Behavior of Polyethylene Reinforced with Nano-sized Alumina
Authors: Tadayyon Gh. , Zebarjad S. M. , Sajjadi S. A.
Published: September 2011

In the current study the dependency of morphology and thermal behavior of medium density polyethylene (MDPE) powder reinforced with 0, 5, 10 and 15 wt.% nano-sized Al2O3 particles on mechanical milling were studied. The effects of milling time on the morphology and the thermal behavior were investigated by Transition Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Differential Scanning Calorimetery (DSC) and Thermo Gravimetric Analyzer (TGA). The TEM micrographs obtained from the nanocomposites proved that mechanical milling could be an adequate method to disperse nano-sized hard particles throughout the polymer. The SEM micrographs of pure MDPE showed that regular shape powder converted to the flake shapes as milling time increased. Also the results illustrated that an increase in milling time caused to decrease the agglomeration of alumina. The DSC profiles of samples elucidated that ball milling had little effect on crystalline temperature and melting point of all materials including MDPE and its nanocomposites. The nanocomposite exhibited more thermal stability than pure polyethylene proved by TGA tests.
Concentration Effects of Organosilane (TESPD) on Mechanical Properties of Silica Filled Silicone Rubber/Natural Rubber Compounds
Authors: Dang T. T. N. , Kim J. K. , Kim K.-J.
Published: September 2011

The concentration effects of the silane coupling agent bis (triethoxysilylpropyl) disulfide (TESPD) on mechanical properties of silica-filled silicone rubber (SR)/natural rubber (NR) compound are investigated upon torque maximum value, tensile strength, tensile modulus and hardness. The compounds are cured with a conventional vulcanization system. The concentration range of the TESPD used is 1 to 17 phr. The optimum concentration of the TESPD is found to be 13 phr in the SR/NR compound. The degree of dispersion of silica in the rubber matrix is also examined by scanning electron microscopy (SEM).
Free Volume from Pressure and Temperature Dependent Viscosity and from PVT Measurements for Homo- and Copolymers
Authors: Halász L. , Huszár A.
Published: September 2011

Pressure and temperature dependency of shear and elongation viscosity and the thermal expansivity and the compressibility determined from PVT data were investigated for propylene homo- and propylene-1-pentene, -1-hexene, 1-heptene and -nonene copolymers and ethylene homopolymer and ethylene-1-butene, 1-pentene and 1-hexene copolymers. The short branching degree dependence of thermal sensitivity and pressure coefficient and the thermal expansivity and the compressibility has been determined. The fractional free volumes were calculated from the viscosity and PVT curves and the thermal expansion coefficient and compressibility factor of fractional free volume were determined. The temperature, pressure and stress dependence of fractional free volume was investigated. The fractional free volume calculated from viscosity data were compared from values comes from PVT measurement. A conversion equation was suggested.
Investigation into the Differences in the Selective Laser Sintering between Amorphous and Semi-crystalline Polymers
Authors: Yan C. , Shi Y. , Hao L.
Published: September 2011

Significant different thermal properties between amorphous and semi-crystalline polymers have a great effect on the selection of proper sintering parameters and the resulting properties of the parts made by selective laser sintering (SLS) process. This paper studied the differences in the part bed temperature (Tb), and relative density, tensile strength and dimensional accuracy of the SLS fabricated parts between semi-crystalline and amorphous polymers, by measuring and comparing the laser sintering properties of polystyrene (PS), a typical amorphous polymer, and nylon-12 (PA12), a typical semi-crystalline polymer. The results show that: the part bed temperatures (Tb) of amorphous polymers and semi-crystalline polymers should be kept close to glass transition temperature (Tg) and initial melting temperature (Tim) respectively, which can be measured by differential scanning calorimetry (DSC), and this rule combined with trial and error experiments can determine Tb of a polymer in the SLS process; the amorphous polymer SLS parts have very low relative densities and much lower tensile strengths than the strengths of their fully dense forms, while the semi-crystalline polymer SLS parts have higher relative densities and their tensile strengths are close to the strengths of their fully dense forms; the dimensional accuracy of the SLS parts of amorphous polymers is higher than that of semi-crystalline polymer SLS parts at the same processing parameters. The obtained results will be helpful for the development of new SLS materials and the setting of processing parameters.
Rheological Modeling and Dynamic Characteristics of Disc Extruders
Authors: Borisov A. A. , Berdyshev B. V. , Hosseini H. , Shirkavand-Hadavand B.
Published: September 2011

Disc extruders have been employed for blending, mixing, dispersing, coloring, homogenizing, degassing, and granulating of polymers. One of the difficulties in the design of disc extruders is the evaluation of dynamic characteristics such as required power, momentum transfer rate, and applied torque, which indeed indicates the capability of the machine and its components. In this paper the required conditions and model for developing of elastic deformation of polymers in the disc extruders are studied. By rheological modeling of disc extruders and related elements, dynamic behavior of this processing system which highly depends on elastic properties of polymeric materials is obtained. These data are necessary for a proper design the system, and more accurate calculation its moving parts.
The Effect of Polymer Additives on Surface Quality of Microcellular Injection Molded Parts
Authors: Lee J. , Turng L.-S. , Peng J. , Dougherty E. , Gorton P.
Published: September 2011

Microcellular injection molding is an emerging process for producing foamed plastic parts with complex geometries. It has many advantages including material, energy, and cost savings as well as greater design freedom and dimensional stability. In spite of these advantages, this technique has been limited to non-aesthetic applications by its propensity to create parts with swirling patterns on the surface, a common characteristic of all foamed parts produced. This paper describes a novel method for achieving microcellular injection molded parts free of surface defects. By controlling the amount of supercritical fluid (SCF) and adding the proper type of polymer additives into the polymer, the onset and rate of cell nucleation were properly controlled so that swirl-free microcellular injection molded parts could be successfully molded. This paper presents the theoretical background and experimental results that demonstrate the effect of polymer additives on the surface quality of microcellular injection molded parts.
Effect of Ionomer on Barrier and Mechanical Properties of PET/Organoclay Nanocomposites Prepared by Melt Compounding
Authors: Xu X. F. , Ghanbari A. , Leelapornpisit W. , Heuzey M. C. , Carreau P.
Published: September 2011

Poly(ethylene terephthalate)/organo-modified-montmorillonite (o-MMT) nanocomposites were prepared via melt compounding. A polyester ionomer was used as a compatibilizer to increase the interaction between the nanoclay and PET. The nominal o-MMT content was 2 wt.% and the ionomer/organoclay (mass ratio) was 3:1. The samples were characterized by WAXD, SEM, TEM, TGA, rheometry, DSC, O2 permeation and tensile testing. It was found that the addition of the ionomer improved the dispersion of the nanoclay particles in the PET matrix, leading to an exfoliated structure for the samples prepared by twin screw extrusion and by an internal mixer (Brabender). This was confirmed by larger complex viscosity and storage modulus at low frequency for molten samples. However, a subsequent processing using single screw extrusion to produce films resulted in thermal degradation of the organo-modifier of the clay and collapse of the gallery spacing. DSC results revealed that the cold crystallization temperature of nanocomposites-based films decreased and the melt crystallization temperature increased with the introduction of the organoclay, due to the strong heterogeneous nucleation effect of the clay particles. The tensile modulus of extruded films increased, while the yield strength remained constant with the incorporation of the organoclay. The oxygen permeability of PET-ionomer nanocomposites decreased as compared with samples containing no ionomer.
UniDA: Uniform Device Access Framework for Human Interaction Environments
Authors: Varela Gervasio , Paz-Lopez Alejandro , Becerra Jose Antonio , Vazquez-Rodriguez Santiago , Duro Richard José
Published: September 2011

Human interaction environments (HIE) must be understood as any place where people carry out their daily life, including their work, family life, leisure and social life, interacting with technology to enhance or facilitate the experience. The integration of technology in these environments has been achieved in a disorderly and incompatible way, with devices operating in isolated islands with artificial edges delimited by the manufacturers. In this paper we are presenting the UniDA framework, an integral solution for the development of systems that require the integration and interoperation of devices and technologies in HIEs. It provides developers and installers with a uniform conceptual framework capable of modelling an HIE, together with a set of libraries, tools and devices to build distributed instrumentation networks with support for transparent integration of other technologies. A series of use case examples and a comparison to many of the existing technologies in the field has been included in order to show the benefits of using UniDA.
Enhancing Medication Adherence by Improving the Clarity of Labels for Prescription Drugs
Authors: Hogan Mary-Ellen
Published: September 2011

Pharmacists maybe contributing to unintentional medication nonadherence in their patients by labelling prescription medications in an unclear way. Many patients have low literacy, and even those with adequate literacy have trouble understanding some prescription label directions. Results of studies determining prevalence of low literacy and low health literacy are reported and studies that demonstrate patient understanding of commonly used label instructions and auxiliary labels are summarized. Strategies that might increase understanding of prescription labels for all literacy levels include using plain language, eliminating unnecessary words and phrases, and managing the way dispensing software translates commonly used abbreviations.
Telbivudine Exerts no Antiviral Activity against HIV-1 In Vitro and in Humans
Authors: van Maarseveen Noortje M , Wensing Annemarie MJ , de Jong Dorien , Beilhartz Greg L , Obikhod Aleksandr , Tao Sijia , Pingen Marieke , Arends Joop E , Hoepelman Andy IM , Schinazi Raymond F , Götte Matthias , Nijhuis Monique
Published: September 2011

Background

HIV–HBV-coinfected individuals who need to be treated only for their HBV infection have limited therapeutic options, since most approved anti-HBV agents have a risk of selecting for drug-resistant HIV mutants. In vivo data are inconclusive as to whether telbivudine (LdT) may exert antiviral effects against HIV. Thus, we investigated in further detail the antiviral activity and the biochemical properties of LdT against HIV-1.

Methods

To investigate the activity of LdT against HIV-1 in humans we analysed viral dynamics and genotypic and phenotypic resistance development in two HIV–HBV-coinfected individuals with no prior antiviral exposure. To investigate the activity of LdT against HIV-1 in vitro, LdT susceptibility for HIV-1 wild-type strains as well as drug-resistant strains was determined. Furthermore, we studied whether the 5′-triphosphate form of LdT (LdT-TP) can act as a substrate for wild-type HIV-1 RT.

Results

In the two patients studied, LdT treatment did not result in a significant decline of HIV-1 RNA load nor in selection of genotypic or phenotypic resistance in HIV-1 RT. In vitro virological analyses demonstrated that LdT had no activity (50% effective concentration >100 μM) against wild type HIV and drug-resistant variants. Biochemical analyses demonstrated that LdT-TP is not incorporated by wild-type HIV-1 RT.

Conclusions

Based on the in vivo and in vitro evidence obtained in this study, we conclude that LdT has no anti-HIV-1 activity and is currently the only selective anti-HBV agent among the five FDA-approved nucleoside/nucleotide analogues for treatment of HBV infections in HIV-infected individuals.
Phenolic profile and antioxidant activity of olive fruits of the Turkish variety “Sarıulak” from different locations
Authors: Arslan D. , Özcan M. M.
Published: September 2011

The phenolic compounds, radical scavenging effect and antioxidant capacity of olive fruits from the “Sarıulak” variety were studied from four different locations: Alanya, Ceyhan, Silifke and Karaman in the Mediterranean region of Turkey. They were collected on three different harvest dates (HDs) and in two consecutive crop years. The levels of most of the phenolic compounds in the fruits of the Alanya location were remarkably high among the values (mg/kg) obtained for all location samples mainly on the first HDs, for instance hydroxytyrosol rose to 3596.4, luteolin rose to 269.5, vanillic acid rose to 159.8 and caffeic acid rose to 62.1. The olive fruits from Alanya, which had the highest average rainfall compared to the other locations, showed the highest phenolic content. The olive fruits from Silifke, which had a dramatic decrease in rainfall between the two crop years, showed a reduction in total phenolic content in the following crop year. The highest oleuropein contents (mg/kg) were detected for the fruit samples grown in Silifke (963.5-2981.8) and for Karaman (835.2-655.6). All of the locations showed similar changes in antioxidant activity pointing to an increase with later HDs. The effect of HD on the phenolic compounds such as 4-hydroxyphenyl acetic acid, caffeic acid, syringic acid and hidroxytyrosol, luteolin, chlorogenic acid and 3,4-dihydroxybenzoic acid were more dependent on the location factor.
Effects of storage and industrial oilseed extraction methods on the quality and stability characteristics of crude sunflower oil (Helianthus annuus L.)
Authors: Tasan M. , Gecgel U. , Demirci M.
Published: September 2011

The influence of industrial oilseed extraction methods on the quality and stability of crude sunflower oil (pre-pressed, solvent-extracted, full-pressed and mixed oils) was studied by means of the determination of free fatty acids, peroxide value, color value, iron, phosphorus, total and individual tocopherol contents, their stability against oxidation (Rancimat induction time) and the fatty acid composition with special emphasis on trans fatty acids. In addition, these crude oils were stored for a period of four months at 40 ± 2°C and analyzed at monthly intervals for free fatty acids, peroxide value, and Rancimat induction time to evaluate their storage stability. The results revealed that the crude sunflower oils obtained by the full-pressed extraction method had worse quality and stability parameters than the crude oils obtained by other extraction methods. Tocopherol content showed a drastic decrease with full-pressed extraction. Also, the crude sunflower oils obtained by the full-pressed extraction presented a higher total trans fatty acid content than the others. On the contrary, the solvent extraction method influenced the phosphorus and iron contents more than the others. The results indicated, however, that pre-pressing the oil appeared to be better than other methods. This study suggests that it is absolutely necessary for the vegetable oil industry to reevaluate the full pressing method as well as the solvent extraction conditions used for sunflowerseeds in order to retain both nutritive value and oxidative stability.