Sample records for sob material da

  1. Computational Modeling of Dynamic Failure Mechanisms in Armor/Anti-Armor Materials

    DTIC Science & Technology

    1991-02-01

    June 1983. Xavier, Celio; Da Costa, Carlos R.C. Estudo do Comportamento Mecanico de Placas de Alumina Sob Impacto Balistico. (A Study of the Mechanical...0 40 10 0.0 La 2.0 SUMMARY OF RESULTS The emphasis of the project in the first two years was to evaluate the literature and survey private industry...of Materials of Interest for Lightweight Armor," Report LA -3858-MS, Los Alamos Scientific Laboratory, Los Alamos, New Mexico, January 22, 1968

  2. Study of heat and salt transport processes in the Espinheiro Channel (Ria de Aveiro)

    NASA Astrophysics Data System (ADS)

    Vaz, Nuno Alexandre Firmino

    O principal objectivo deste trabalho consistiu no estudo da dinâmica termohalina do Canal do Espinheiro em funcao de dois forcamentos principais: mare e caudal fluvial, usando duas abordagens distintas: trabalho experimental e modelacao numerica. A propagacao da mare e o caudal fluvial do Rio Vouga sao determinantes no estabelecimento da estrutura horizontal da salinidade ao longo do canal. A estrutura termica horizontal ao longo do canal e, em grande parte, determinada pela variacao sazonal da temperatura da agua do Rio Vouga, bem como, pela variacao sazonal das condicoes meteorologicas devido a reduzida profundidade. Foi observada a formacao de fortes gradientes de salinidade (relacionados com a formacao de frentes estuarinas) numa regiao a cerca de 7-8 km da embocadura do canal, observando-se a sua migracao numa regiao de aproximadamente 1 km, dependendo do regime de mare. O balanco entre o transporte de sal de natureza advectiva e difusiva foi calculado, revelando que junto a embocadura os processos fisicos que mais contribuem para o transporte de sal sao a circulacao residual e o aprisionamento da agua em canais secundarios. Junto a foz do Rio Vouga os termos devidos a descarga fluvial e a circulacao gravitacional dominam o transporte de sal. Foi calibrado e validado um modelo numerico (Mohid, em modo 2D e 3D), sendo posteriormente utilizado para estudar a hidrologia do canal. Foi concedida particular atencao ao estudo da hidrologia em condicoes extremas de caudal fluvial e de mare. Os resultados da modelacao numerica permitiram numa primeira fase avaliar o bom desempenho do Mohid na reproducao dos escoamentos barotropicos na Ria de Aveiro, bem como na evolucao temporal das propriedades termohalinas da agua. Sob condicoes de caudal fluvial reduzido, a dinâmica do canal e essencialmente dominada pela mare. Com o aumento do caudal fluvial, a influencia da agua doce estende-se para jusante, estratificando a coluna de agua. As simulacoes 3D do Canal do Espinheiro foram efectuadas para periodos marcadamente diferentes de caudal fluvial e de mare. O modelo reproduziu qualitativamente/quantitativamente as observacoes de alturas de agua, velocidade e distribuicoes longitudinais de salinidade e temperatura sob um regime fraco a medio de caudal fluvial. Sob condicoes de caudal fluvial elevado, os resultados mostram que o modelo subestima a estratificacao. Este estudo contribuiu para o aumento do conhecimento da dinâmica do Canal do Espinheiro, bem como para o desenvolvimento de um sistema numerico capaz de reproduzir e prever os processos de transporte de sal e calor. None

  3. Thin films for gas sensors

    NASA Astrophysics Data System (ADS)

    Pires, Jose Miguel Alves Correia

    Nos ultimos anos tem-se assistido a um aumento dos investimentos na investigacao de novos materiais para aplicacao em sensores. Apesar de ja existir um bom numero de dispositivos explorados comercialmente, muitas vezes, quer devido aos elevados custos de producao, quer devido a uma crescente exigencia do ponto de vista das caracteristicas de funcionamento, continua a ser necessario procurar novos materiais ou novas formas de producao que permitam baixar os custos e melhorar o desempenho dos dispositivos. No campo dos sensores de gases tem-se verificado continuos avancos nos ultimos anos. Continua todavia a ser necessario conhecer melhor, tanto os processos de producao dos materiais, como os mecanismos que regulam a sensibilidade dos dispositivos aos gases, de modo a orientar adequadamente a investigacao dos novos materiais, nomeadamente no que se refere a optimizacao dos parâmetros que nao satisfazem ainda os requisitos do mercado. Um dos materiais que tem mostrado melhores qualidades para aplicacao em sensores de gases de tipo resistivo e o dioxido de estanho. Este material tem sido produzido sob diversas formas e usando diferentes tecnicas, como sejam: sol-gel [1], pulverizacao catodica (sputtering) por magnetrao [2-4], sinterizacao de pos [5, 6], ablacao laser [7] ou RGTO [8]. Os resultados obtidos revelam que as caracteristicas dos dispositivos sao muito dependentes das tecnicas usadas na sua producao. A deposicao usando sputtering reactivo por magnetrao e uma tecnica que permite obter filmes finos de oxido de estanho com diferentes caracteristicas, quer do ponto de vista da estrutura, quer da composicao, e por isso, tambem, com diferentes sensibilidades aos gases. No âmbito deste trabalho, foram produzidos filmes de SnO2 usando sputtering DC reactivo com diferentes condicoes de deposicao. Os substratos usados foram lâminas de vidro e o alvo foi estanho com 99.9% de pureza. Foi estudada a influencia da atmosfera de deposicao, da pressao parcial do O2, da temperatura do substrato e da potencia da descarga na estrutura do material depositado. Durante a deposicao, alem dos parâmetros ja referidos, foram tambem registados a pressao de base antes da entrada dos gases de sputtering, os fluxos de oxigenio e argon durante a deposicao, a distância alvo-substrato, o tempo de deposicao, a corrente e a tensao aplicadas ao magnetrao. Foram feitas algumas experiencias usando uma fonte RF, para comparacao. (Abstract shortened by ProQuest.).

  4. Effectiveness of spinal anesthesia combined with obturator nerve blockade in preventing adductor muscle contraction during transurethral resection of bladder tumor

    PubMed Central

    Alavi, Cyrus Emir; Asgari, Seyed Alaeddin; Falahatkar, Siavash; Rimaz, Siamak; Naghipour, Mohammadreza; Khoshrang, Hossein; Jafari, Mehdi; Herfeh, Nadia

    2017-01-01

    Objective To determine whether spinal anesthesia combined with obturator nerve blockade (SOB) is effective in preventing obturator nerve stimulation, jerking and bladder perforation during transurethral resection of bladder tumor (TURBT). Material and methods In this clinical trial, 30 patients were randomly divided into two groups: spinal anesthesia (SA) and SOB. In SA group, 2.5 cc of 0.5% bupivacaine was injected intrathecally using a 25-gauge spinal needle and in SOB after spinal anesthesia, a classic obturator nerve blockade was performed by using nerve stimulation technique. Results There was a statistically significant difference between jerking in both groups (p=0.006). During the TURBT, surgeon satisfaction was significantly higher in SOB group compared to SA group (p=0.006). There was no significant correlation between sex, patient age and location of bladder tumor between the groups (p>0.05). Conclusion Obturator nerve blockade by using 15 cc lidocaine 1% is effective in preventing adductor muscle spasms during TURBT. PMID:29201516

  5. Learning of Unknown Environments in Goal-Directed Guidance and Navigation Tasks: Autonomous Systems and Humans

    NASA Astrophysics Data System (ADS)

    Vidal, Joao Vasco Silvestres

    Este trabalho expoe um estudo teorico e experimental das propriedades anisotropicas magnetoeletricas (ME) em diferentes compositos contendo monocristais piezoeletricos (PE), maioritariamente sem chumbo na sua composicao, com vista a diversas aplicacoes multifuncionais. Uma descricao linear do efeito ME em termos de campos eletricos, magneticos e elasticos e constantes materiais e apresentada. Um modelo fenomenologico quasi-estatico e usado para ilustrar a relacao entre as constantes materiais, sua anisotropia e os coeficientes MEs transversais de tensao e carga. Subsequentemente, este modelo e empregue para estimar o maximo coeficiente ME direto de tensao expectavel numa serie de compositos tri-camadas de Metglas/Piezocristal/Metglas em funcao da orientacao do cristal PE. Demonstra-se assim como os efeitos MEs sao fortemente dependentes da orientacao cristalina, o que suporta a possibilidade de se gerarem coeficientes MEs de tensao elevados em compositos contendo monocristais PEs sem chumbo como o niobato de litio (LiNbO3; LNO), tantalato de litio (LiTaO3), ortofosfato de galio (GaPO4; GPO), quartzo (SiO2), langatato (La3Ga5.5Ta0.5O14) e langasite (La3Ga5SiO14) atraves da otimizacao da orientacao cristalina. Uma tecnica experimental dinâmica de lock-in para a medicao da impedância e efeito ME direto e exposta. O formalismo descritivo desta tecnica, assim como um arranjo experimental desenvolvido para o efeito sao apresentados. O esquema e caracteristicas deste, assim como diferentes formas de reduzir o ruido e a indesejavel inducao mutua sao exploradas. Um estudo comparativo do efeito ME direto em compositos tri-camadas de Metglas e monocristais de LNO e PMN-PT conectados de forma simples e exposto. Embora o PMN-PT possua piezocoeficientes de carga muito superiores aos do LNO, o coeficiente ME direto de tensao demonstrou-se comparavel entre ambos os compositos devido a uma muito menor permitividade dieletrica do LNO. Calculos teoricos indicam ainda que as propriedades MEs poderao ser significativamente melhoradas (ate 500 V/(cm.Oe)) atraves da otimizacao do ângulo de corte do LNO, espessura relativa entre camadas ferroeletrica/ferromagnetica e uma melhor colagem entre o Metglas e o LNO. Vantagens da utilizacao do material ferroeletrico LNO em compositos MEs sao discutidas. Num estudo subsequente, as propriedades dinâmicas anisotropicas de impedância e MEs em compositos tri-camadas de Metglas e monocristais PEs sem chumbo de LNO e GPO sao exploradas. Medicoes foram realizadas em funcao do corte de cristal, magnitude e orientacao do campo magnetico de polarizacao e frequencia do campo de modulacao. Coeficientes MEs altamente intensos em certos modos de ressonância sao explorados, e a sua relacao com as propriedades materiais dos cristais e geometria dos compositos e investigada. Um coeficiente ME de ate 249 V/(cm.Oe) foi aqui observado num composito com um cristal de LNO com corte 41ºY a 323.1 kHz. Mostramos assim que compositos multicamadas contendo cristais sem chumbo de LNO e GPO podem exibir efeitos MEs anisotropicos relativamente elevados. Demonstramos tambem que o controlo da orientacao dos cristais PEs pode em principio ser usado na obtencao de propriedades MEs anisotropicas desejaveis para qualquer aplicacao. Caracteristicas unicas como elevada estabilidade quimica, piezoeletricidade linear e robusteza termica abrem verdadeiras perspetivas para a utilizacao de compositos baseados no LNO e GPO em diversas aplicacoes. Eventualmente, compositos bi-camadas contendo lâminas PEs com bidominios de LNO com corte 127ºY foram estudados tanto teoricamente como experimentalmente. Estas lâminas de LNO possuem uma estrutura de bidominios com vetores de polarizacao espontânea opostos ao longo da direcao da sua espessura (i.e. uma estrutura de macrodominios ferroeletricos "head-to-head" ou "tail-to-tail") Medicoes de impedância, efeito ME e densidade de ruido magnetico equivalente foram realizadas nos compositos operando sob condicoes quasi-estaticas e de ressonância. Coeficientes MEs de ate 578 V/(cm.Oe) foram obtidos a ca. 30 kHz sob ressonâncias de dobramento usando cristais PEs com 0.5 mm de espessura. Medicoes de densidade de ruido magnetico equivalente demosntraram valores de ate 153 pT/Hz1/2 a 1 kHz (modo quasi-estatico) e 524 fT/Hz1/2 sob condicoes de ressonância. E de esperar que uma otimizacao adicional das tecnicas de fabrico, geometria dos compositos e circuitos de detencao possa permitir reduzir estes valores ate pelo menos 10 pT/Hz1/2 e 250 fT/Hz1/2, respetivamente, e a frequencia de ressonância em pelo menos duas ordens de grandeza. Estes sistemas poderao assim no futuro ser usados em sensores vetoriais de campo magnetico simples e sensiveis, passivos e estaveis e operaveis a elevadas temperaturas. None

  6. Preparation and characterization of novel nanocomposites of inorganic/polysaccharide type =

    NASA Astrophysics Data System (ADS)

    Oliveira, Fabiane Costa

    O uso de polimeros naturais no ambito da preparacao de nanocompositos nao tem sido tao amplamente estudado quando comparado com os polimeros sinteticos. Assim, esta tese tem como objectivo estudar metodologias para a preparacao de novos materiais nanocompositos sob a forma de dispersoes e filmes utilizando polissacarideos como matriz. A tese esta dividida em cinco capitulos sendo o ultimo capitulo dedicado as conclusoes gerais e a sugestoes para trabalhos futuros. Inicialmente e apresentada uma breve revisao bibliografica sobre os principais temas colocando esta tese em contexto. Consideracoes sobre o uso de polimeros naturais e a sua combinacao com a utilizacao de nanoparticulas inorganicas para a fabricacao de novos bionanocomposites sao descritas e os objectivos e outline da tese sao tambem apresentados. No segundo capitulo, a preparacao de particulas de silica puras ou modificadas bem como a sua caracterizacao por FTIR, SEM, TEM, TGA, DLS (tamanho e potencial zeta) e medicoes de angulo de contacto sao discutidas. De modo a melhorar a compatibilidade da silica com os polissacarideos, as particulas SiO2 foram modificados com dois compostos do tipo organosilano: 3- metacril-oxipropil-trimetoxissilano (MPS) e 3-aminopropil-trimetoxissilano (APS). As particulas SiO2 MPS foram posteriormente encapsuladas com de poli(metacrilato de glicidilo) utilizando a tecnica de polimerizacao em emulsao. A utilizacao dos nanocompositos resultantes na preparacao de dispersoes de bionanocompositos nao foi bem sucedida e por esse motivo nao os estudos nao foram prosseguidos. O uso de SiO2 APS na preparacao de dispersoes bionanocomposite foi eficiente. No terceiro capitulo e apresentada uma revisao sobre dispersoes bionanocompositas e respectiva caracterizacao destacando aspectos fundamentais sobre reologia e microestrutura. Em seguida, e discutido o estudo sistematico realizado sobre o comportamento reologico de dispersoes de SiO2 utilizando tres polissacarideos distintos no que concerne a carga e as caracteristicas gelificantes: a goma de alfarroba (nao ionica), o quitosano (cationico) e a goma xantana (anionica) cujas propriedades reologicas sao amplamente conhecidas. Os estudos reologicos realizados sob diferentes condicoes demonstraram que a formacao de geis frageis e/ou bem estruturados depende do tamanho SiO2, da concentracao, do pH e da forca ionica. Estes estudos foram confirmados por analises microestruturais usando a microscopia electronica a baixas temperaturas (Cryo-SEM). No quarto capitulo, sao apresentados os estudos relativos a preparacao e caracterizacao de filmes bionanocompositos utilizando quitosano como matriz. Primeiramente e apresentada uma revisao sobre filmes de bionanocompositos e os aspectos fundamentais das tecnicas de caracterizacao utilizadas. A escolha do plasticizante e da sua concentracao sao discutidas com base nas propriedades de filmes de quitosano preparados. Em seguida, o efeito da concentracao de silica e dos metodos utilizados para a dispersar na matriz de polissacarideo, bem como o efeito da modificacao da superficie da silica e avaliado. As caracteristicas da superficie e as propriedades de barreira, mecanicas e termicas sao discutidas para cada conjunto de filmes preparados antes e apos a sua neutralizacao. Os resultados obtidos mostraram que a dispersao das cargas no plasticizante e posterior adicao a matriz polissacaridica resultaram apenas em pequenas melhorias ja que o problema da agregacao de silica nao foi ultrapassado. Por esse motivo foram preparados filmes com SiO2 APS os quais apresentaram propriedades melhores apesar da agregacao das particulas nao ter sido completamente impedida. Tal pode estar relacionado com o processo de secagem dos filmes. Finalmente, no capitulo 5, sao apresentadas as principais conclusoes obtidas e algumas sugestoes para trabalho futuro.

  7. Use of technologies in intravenous therapy: contributions to a safer practice.

    PubMed

    Moreira, Ana Paula Amorim; Escudeiro, Cristina Lavoyer; Christovam, Bárbara Pompeu; Silvino, Zenith Rosa; Carvalho, Márglory Fraga de; Silva, Roberto Carlos Lyra da

    2017-01-01

    To identify what are the difficulties of the nursing staff in the management of technologies during intravenous therapy (IVT) and discuss the difficulties identified under the perspective of patient's safety. Descriptive study of qualitative approach with data collected by semi-structured interview and analyzed by the Alceste software. The greatest difficulty of cognitive and technical emphasis was the lack of training; and regarding administrative emphasis, the greatest difficulty was the lack of material and human resources. Infusion pumps and their proper use were highlighted as the technological resource that most contributed to patient safety. The lack of training is presented as the greatest difficulty of nursing professionals and permeates safety issues of both patient and professional when using the hard technologies in IVT. Training is essential to the development of techniques, considered nursing tools. Identificar quais são as dificuldades da equipe de Enfermagem no manejo das tecnologias durante a terapia intravenosa (TIV) e discutir as dificuldades identificadas sob a perspectiva da segurança do paciente. abordagem qualitativa, do tipo descritivo com dados coletados por entrevista semiestruturada e analisados pelo programa Alceste. A maior dificuldade de ênfase cognitiva e técnica foi a falta de treinamento; e de ênfase administrativa, foi a falta de recursos materiais e humanos. As bombas de infusão e sua utilização adequada foram destacadas como o recurso tecnológico que mais contribuiu para a segurança do paciente. A falta de treinamento é apresentada como a maior dificuldade dos profissionais de Enfermagem e permeia as questões de segurança do paciente e do profissional ao utilizar as tecnologias duras na TIV. O treinamento é imprescindível para o desenvolvimento das técnicas, consideradas como ferramentas do fazer da Enfermagem.

  8. Influence of maxillary posterior discrepancy on upper molar vertical position and facial vertical dimensions in subjects with or without skeletal open bite

    PubMed Central

    Aliaga-Del Castillo, Aron; Pérez-Vargas, Luis Fernando; Flores-Mir, Carlos

    2016-01-01

    Summary Objectives: To determine the influence of maxillary posterior discrepancy on upper molar vertical position and dentofacial vertical dimensions in individuals with or without skeletal open bite (SOB). Materials and methods: Pre-treatment lateral cephalograms of 139 young adults were examined. The sample was divided into eight groups categorized according to their sagittal and vertical skeletal facial growth pattern and maxillary posterior discrepancy (present or absent). Upper molar vertical position, overbite, lower anterior facial height and facial height ratio were measured. Independent t-test was performed to determine differences between the groups considering maxillary posterior discrepancy. Principal component analysis and MANCOVA test were also used. Results: No statistically significant differences were found comparing the molar vertical position according to maxillary posterior discrepancy for the SOB Class I group or the group with adequate overbite. Significant differences were found in SOB Class II and Class III groups. In addition, an increased molar vertical position was found in the group without posterior discrepancy. Limitations: Some variables closely related with the individual’s intrinsic craniofacial development that could influence the evaluated vertical measurements were not considered. Conclusions and implications: Overall maxillary posterior discrepancy does not appear to have a clear impact on upper molar vertical position or facial vertical dimensions. Only the SOB Class III group without posterior discrepancy had a significant increased upper molar vertical position. PMID:26385786

  9. Mechanical behaviour of AlSiC nano composites produced by ball milling and spark plasma sintering =

    NASA Astrophysics Data System (ADS)

    Buchheim, Claudia Sofia de Andrade Redondo Murilhas

    Neste trabalho foram produzidos nanocompositos de AlSiC misturando aluminio puro com nano particulas de SiC com diâmetro de 45 - 55 nm, usando, de forma sequencial, a tecnica da metalurgia do po e a compactacao por "Spark Plasma Sintering". O composito obtido apresentava graos com 100 nm de diâmetro, encontrandose as particulas de SiC localizadas, principalmente, nas fronteiras de grao. O nanocomposito sob a forma de provetes cilindricos foi submetido a testes de compressao uniaxial e a testes de nanoindentacao para analisar a influencia das nanoparticulas de SiC, da fracao volumica de acido estearico e do tempo de moagem, nas propriedades mecânicas do material. Para efeitos de comparacao, utilizouse o comportamento mecânico do Al puro processado em condicoes similares e da liga de aluminio AA1050O. A tensao limite de elasticidade do nanocomposito com 1% Vol./Vol. de SiC e dez vezes superior a do AA1050. O refinamento de grao a escala nano constitui o principal mecanismo de aumento de resistencia mecânica. Na realidade, o Al nanocristalino sem reforco de particulas de SiC, apresenta uma tensao limite de elasticidade sete vezes superior a da liga AA1050O. A adicao de 0,5 % Vol./Vol. e de 1 % Vol./Vol. de SiC conduzem, respetivamente, ao aumento da tensao limite de elasticidade em 47 % e 50%. O aumento do tempo de moagem e a adicao de acido estearico ao po durante a moagem conduzem apenas a um pequeno aumento da tensao de escoamento. A dureza do material medida atraves de testes de nanoindentacao confirmaram os dados anteriores. A estabilidade das microestruturas do aluminio puro e do nanocomposito AlSiC, foi testada atraves de recozimento de restauracao realizado as temperaturas de 150 °C e 250 °C durante 2 horas. Aparentemente, o tratamento termico nao influenciou as propriedades mecânicas dos materiais, excepto do nanocomposito com 1 % Vol./Vol. de SiC restaurado a temperatura de 250 °C, para o qual se observou uma reducao da tensao limite de elasticidade na ordem dos 13 %. No aluminio nanocristalino, a tensao de escoamento e controlada pelo efeito de HallPetch. As particulas de SiC, sao segregadas pelas fronteiras do grao e nao contribuem para o aumento de resistencia mecânica segundo o mecanismo de Orowan. Alternativamente, as nanoparticulas de SiC constituem um reforco das fronteiras do grao, impedindo o seu escorregamento e estabilizando a nanoestrutura. Deste modo, as propriedades mecânicas do aluminio nanocristalino e do nanocomposito de AlSiC poderao estar relacionadas com a facilidade ou dificuldade do escorregamento das fronteiras de grao, embora nao seja apresentada prova explicita deste mecanismo a temperatura ambiente.

  10. Modeling month-season of birth as a risk factor in mouse models of chronic disease: from multiple sclerosis to autoimmune encephalomyelitis.

    PubMed

    Reynolds, Jacob D; Case, Laure K; Krementsov, Dimitry N; Raza, Abbas; Bartiss, Rose; Teuscher, Cory

    2017-06-01

    Month-season of birth (M-SOB) is a risk factor in multiple chronic diseases, including multiple sclerosis (MS), where the lowest and greatest risk of developing MS coincide with the lowest and highest birth rates, respectively. To determine whether M-SOB effects in such chronic diseases as MS can be experimentally modeled, we examined the effect of M-SOB on susceptibility of C57BL/6J mice to experimental autoimmune encephalomyelitis (EAE). As in MS, mice that were born during the M-SOB with the lowest birth rate were less susceptible to EAE than mice born during the M-SOB with the highest birth rate. We also show that the M-SOB effect on EAE susceptibility is associated with differential production of multiple cytokines/chemokines by neuroantigen-specific T cells that are known to play a role in EAE pathogenesis. Taken together, these results support the existence of an M-SOB effect that may reflect seasonally dependent developmental differences in adaptive immune responses to self-antigens independent of external stimuli, including exposure to sunlight and vitamin D. Moreover, our documentation of an M-SOB effect on EAE susceptibility in mice allows for modeling and detailed analysis of mechanisms that underlie the M-SOB effect in not only MS but in numerous other diseases in which M-SOB impacts susceptibility.-Reynolds, J. D., Case, L. K., Krementsov, D. N., Raza, A., Bartiss, R., Teuscher, C. Modeling month-season of birth as a risk factor in mouse models of chronic disease: from multiple sclerosis to autoimmune encephalomyelitis. © FASEB.

  11. Discos de acresção em sistemas Be-X

    NASA Astrophysics Data System (ADS)

    Lopes de Oliveira, R.; Janot-Pacheco, E.

    2003-08-01

    Alguns fenômenos de outbursts em Be-X sugerem a existência, mesmo que temporária, de um disco de acresção quando da passagem do objeto compacto pelo periastro orbital. Neste trabalho avaliamos a possibilidade de formação do disco de acresção em sistemas Be+estrela de neutrons e Be+anã branca, e a influência da excentricidade orbital na ocorrência deste fenômeno. Utilizamos a expressão analítica para o momento angular específico da matéria constituinte de um meio em expansão lenta, como é o caso do disco circunstelar das estrelas Be, proposta por Wang(1981), sob a condição básica de que o raio de circularização deva ser maior do que o raio de Alfvén. Concluímos que existe um limite para o período orbital do sistema acima do qual não é possível a formação do disco de acresção, e que este valor aumenta para sistemas com excentricidade orbital maior.

  12. Enhanced elementary sulfur recovery in integrated sulfate-reducing, sulfur-producing rector under micro-aerobic condition.

    PubMed

    Xu, Xi-jun; Chen, Chuan; Wang, Ai-jie; Fang, Ning; Yuan, Ye; Ren, Nan-qi; Lee, Duu-jong

    2012-07-01

    Biological treatment of sulfate-laden wastewater consists of two separate reactors to reduce sulfate to sulfide by sulfate-reducing bacteria (SRB) and to oxidize sulfide to sulfur (S(0)) by sulfide oxidation bacteria (SOB). To have SRB+SOB in a single reactor faced difficulty of low S(0) conversion. This study for the first time revealed that dissolved oxygen (DO) level can be used to manipulate SRB+SOB reactions in a single reactor. This work demonstrated successful operation of an integrated SRB+SOB reactor under micro-aerobic condition. At DO = 0.10-0.12 mg l(-1), since the activities of SOB were enhanced by limited oxygen, the removal efficiency for sulfate reached 81.5% and the recovery of S(0) peaked at 71.8%, higher than those reported in literature. At increased DO, chemical oxidation of sulfide with molecular oxygen competed with SOB so conversion of S(0) started to decline. At DO>0.30 mg l(-1) activities of SRB were inhibited, leading to failure of the SRB+SOB reactor. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Season of birth bias in eating disorders--fact or fiction?

    PubMed

    Winje, Eirin; Willoughby, Kate; Lask, Bryan

    2008-09-01

    A season of birth (SoB) bias is said to be present if the SoB pattern for a particular group varies from the pattern within the normal population. Significant biases have been found for several disorders including eating disorders (EDs). This article critically reviews the existing literature on SoB in ED in order to inform future hypothesis-based research. A literature search identified 12 papers investigating SoB in ED. Despite methodological differences, the studies consistently show a SoB bias for anorexia nervosa (AN) in the spring months, in both the northern and southern Hemispheres. This is especially strong for early-onset and restrictive subtype of AN. These findings suggest that SoB is a risk factor for AN. However, none of the studies have been methodologically satisfactory. Future research needs to overcome numerous methodological challenges and to explore specific hypotheses to explain this bias. (c) 2008 by Wiley Periodicals, Inc.

  14. Prediction of individual season of birth using MRI.

    PubMed

    Pantazatos, Spiro P

    2014-03-01

    Previous research suggests statistical associations between season of birth (SOB) with prevalence of neurobehavioral disorders such as schizophrenia and bipolar disorder, personality traits such as novelty and sensation seeking, and suicidal behavior. These effects are thought to be mediated by seasonal differences in perinatal photoperiod, which was recently shown to imprint circadian clock neurons and behavior in rodents. However, it is unknown whether SOB is associated with any measurable differences in the normal human adult brain, and whether individual SOB can be deduced based on phenotype. Here I show that SOB predicts morphological differences in brain structure, and that MRI scans carry spatially distributed information allowing significantly above chance prediction of an individual's SOB. Using an open source database of over 550 structural brain scans, Voxel-Based Morphometry (VBM) analysis showed a significant SOB effect in the left superior temporal gyrus (STG) in males (p=0.009, FWE whole-brain corrected), with greater gray matter volumes in fall and winter births. A cosinor analysis revealed a significant annual periodicity in the left STG gray matter volume (Zero Amplitude Test: p<5×10(-7)), with a peak towards the end of December and a nadir towards the end of June, suggesting that perinatal photoperiod accounts for this SOB effect. Whole-brain VBM maps were used as input features to multivariate machine-learning based analyses to classify SOB. Significantly greater than chance prediction was achieved in females (overall accuracy 35%, p<0.001), but not in males (overall accuracy 26%, p=0.45). Pairwise binary classification in females revealed that the highest discrimination was obtained for winter vs. summer classification (peak area under the ROC curve=0.71, p<0.0005). Discriminating regions included fusiform and middle temporal gyrus, inferior and superior parietal lobe, cerebellum, and dorsolateral and dorsomedial prefrontal cortex. Results indicate that SOB is detectable with MRI, imply that SOB exerts effects on the developing human brain that persist through adulthood, and suggest that neuroimaging may be a valuable intermediate phenotype in bridging the gap between SOB and personality and neurobehavioral disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Self-referencing thermometry in the nanoscale =

    NASA Astrophysics Data System (ADS)

    Brites, Carlos Antonio Delgado Sousa

    Na ultima decada emergiu uma linha de investigacao muito activa em termometros nao invasivos e precisos que possam determinar temperatura a escala nanometrica. Esta investigacao foi fortemente estimulada pelas numerosas solicitacoes da nanotecnologia e da biomedicina, por exemplo. Uma das abordagens mais promissoras propoe o uso de ioes trivalentes de lantanideos que apresenta propriedades fotoluminescentes que dependem da temperatura. Neste trabalho demonstra-se que esta tecnica combina as vantagens de te um limite de deteccao de 0.5 graus com sensibilidade ate 4.5 % K-1. Este termometro molecular pode ser processado em filmes finos ou nanoparticulas, abrindo os campos de aplicacao a diferentes utilizacoes. As nanoparticulas de silica produzidas sao caracterizadas na presenca e na ausencia de ioes lantanideos. Sem o metal, as nanoparticulas de APTES/TEOS demonstram ser luminescentes sob excitacao UV sem necessidade de utilizar qualquer tratamento termico. O rendimento quantico de emissao depende apenas da proporcao dos silanos e pode atingir o valor de 0.15 +/- 0.02. A co-dopagem destas nanoparticulas com Eu3+ e Tb3+ permite obter sondas com resposta raciometrica, com a possibilidade de ajustar a gama de temperaturas de operacao e a sensibilidade, via desenho inteligente da matriz de suporte e dos ligandos de beta-dicetona que estao coordenados ao iao metalico. Quando processados como filmes, este termometro permite o mapeamento de temperaturas com resolucao espacial 1.8 mum. A racionalizacao da dependencia de temperatura e uma ferramenta util para desenvolver termometros que operam em gamas de temperatura especificos (e.g. gama de temperatura fisiologica, 290-340 K) com sensibilidade acima de 0.5 % K-1. A combinacao de esforcos de um grande numero de diversas disciplinas ira previsivelmente permitir o surgimento de termometros moleculares novos e sofisticados, preenchendo os principais requisitos das nanociencias.

  16. Simulações Numéricas de Rotação Nuclear Cometária

    NASA Astrophysics Data System (ADS)

    Voelzke, M. R.; Winter, O. C.

    1999-08-01

    Este trabalho apresenta os resultados iniciais de simulações numéricas da evolução rotacional, de um núcleo cometário não esférico, ao longo de uma passagem periélica, levando-se em conta os torques devido a existência dos jatos de poeira e de gás. Inicialmente os autores apresentam um modelo simples (primeira aproximação), com somente um único jato na extremidade do semi-eixo maior, para compreender a variação positiva ou negativa que estas forças não gravitacionais exercem sobre o período de rotação cometário. Posteriormente incrementa-se o número de jatos, os quais são distribuídos ao longo da superfície cometária, para observar-se a contribuição dos efeitos provenientes dos torques originários da liberação da poeira e gás cometários, que provavelmente violará a suposição da livre precessão. Os estados rotacionais, sob torques induzidos devido à sublimação, dependem fortemente da localização das áreas ativas do núcleo. Os cometas P/Schwassmann-Wachmann 1, P/Tempel 2, P/Forbes e C/Meunier-Dupouy serão observados fotometricamente, pelos autores, no Laboratório Nacional de Astrofísica (LNA) ao longo de algumas noites consecutivas em abril, junho e julho de 1999. Estas observações serão comparadas com as simulações numéricas de rotação cometária.

  17. Experiences in the Family Health Strategy: demands and vulnerabilities in the territory.

    PubMed

    Pinto, Antonio Germane Alves; Jorge, Maria Salete Bessa; Marinho, Mirna Neyara Alexandre de Sá Barreto; Vidal, Emery Ciana Figueirêdo; Aquino, Priscila de Souza; Vidal, Eglídia Carla Figueirêdo

    2017-01-01

    To understand the daily demands of Family Health Strategy in clinical practice of the team and social vulnerabilities of community territory. Research with qualitative approach, in a critical-reflexive perspective, held with two teams of the Family Health Strategy, in the city of Fortaleza, State of Ceará, Brazil. The participants were 22 users and 19 health professionals from the basic health network. Data from the interviews and observation were analyzed under the assumptions of critical hermeneutics. We highlight the unveiling of sufferings and daily clashes, the influence of social determinants on health and psychosocial demands, limits and possibilities of everyday clinical practice. The clinic attention must recognize the perceptions and living conditions by listening and promoting health in the community. Compreender as demandas cotidianas da Estratégia Saúde da Família na prática clínica da equipe e as vulnerabilidades sociais do território comunitário. Pesquisa com abordagem qualitativa, numa perspectiva crítico-reflexiva, realizada com duas equipes da Estratégia Saúde da Família, no município de Fortaleza, Estado do Ceará, Brasil. Os participantes foram 22 usuários e 19 profissionais de saúde da rede básica de saúde. Os dados das entrevistas e observação foram analisados sob os pressupostos da hermenêutica crítica. Evidenciam-se o desvelamento de sofrimentos e enfrentamentos cotidianos, a influência dos determinantes sociais na saúde e as demandas psicossociais, limites e possibilidades da prática clínica cotidiana. Considera-se que a atenção clínica deve reconhecer as percepções e condições de vida pela escuta e ações de promoção de saúde na comunidade.

  18. The essence of care in health vulnerability: a Heideggerian construction.

    PubMed

    Cestari, Virna Ribeiro Feitosa; Moreira, Thereza Maria Magalhães; Pessoa, Vera Lúcia Mendes de Paula; Florêncio, Raquel Sampaio; Silva, Maria Rocineide Ferreira da; Torres, Raimundo Augusto Martins

    2017-01-01

    Reflect on the essence of care in health vulnerability from the phenomenological perspective of Martin Heidegger. Theoretical-reflexive study, anchored in three essential parts: 1) Care in Heidegger; 2) The essence of care in health vulnerability; And 3) Nursing care actions on health vulnerability. Vulnerability must be recognized as an indelible trait of the human condition and has its constituents in the human being, co-presence and care. Caring is an interactive process that reveals itself in the relationship with the other. Respecting the integrity of the Being in vulnerability must be a priority in nursing care, through behaviors that privilege the Being. Understanding ontological care and its relation to vulnerability under Heidegger's phenomenological view allowed us to uncover the facets of care in health vulnerability by adding to the nursing knowledge body a comprehensive and reflective perspective. Refletir sobre a essência do cuidado na vulnerabilidade em saúde sob a perspectiva fenomenológica de Martin Heidegger. Estudo teórico-reflexivo, ancorado em três partes essenciais: 1) O cuidado em Heidegger; 2) A essência do cuidado na vulnerabilidade em saúde; e 3) As ações do cuidar em enfermagem na vulnerabilidade em saúde. A vulnerabilidade deve ser reconhecida como traço indelével da condição humana e tem seus constituintes na pessoa humana, co-presenças e cuidado. O cuidar é um processo interativo que se desvela na relação com o outro. Respeitar a integridade do Ser em vulnerabilidade deve ser prioridade no cuidar em enfermagem, por meio de comportamentos que privilegiem o Ser. Compreender ontologicamente o cuidado e a sua relação com a vulnerabilidade sob o olhar fenomenológico de Heidegger permitiu desvelar as facetas do cuidado na vulnerabilidade em saúde, agregando ao corpo de conhecimento da Enfermagem uma perspectiva compreensiva e reflexiva.

  19. Isolation and characterization of Acidithiobacillus caldus from a sulfur-oxidizing bacterial biosensor and its role in detection of toxic chemicals.

    PubMed

    Hassan, Sedky H A; Van Ginkel, Steven W; Kim, Sung-Min; Yoon, Sung-Hwan; Joo, Jin-Ho; Shin, Beom-Soo; Jeon, Byong-Hun; Bae, Wookeun; Oh, Sang-Eun

    2010-08-01

    A novel toxicity detection methodology based on sulfur-oxidizing bacteria (SOB) has been developed for the rapid and reliable detection of toxic chemicals in water. The methodology exploits the ability of SOB to oxidize sulfur particles in the presence of oxygen to produce sulfuric acid. The reaction results in an increase in electrical conductivity (EC) and a decrease in pH. The assay is based on the inhibition of SOB in the presence of toxic chemicals by measuring changes in EC and pH. We found that SOB biosensor can detect toxic chemicals, such as heavy metals and CN-, in the 5-2000ppb range. One bacterium was isolated from an SOB biosensor and the 16S rRNA gene of the bacterial strain has 99% and 96% sequence similarity to Acidithiobacillus sp. ORCS6 and Acidithiobacillus caldus DSM 8584, respectively. The isolate was identified as A. caldus SMK. The SOB biosensor is ideally suited for monitoring toxic chemicals in water having the advantages of high sensitivity and quick detection.

  20. Eventos de Desconexão no Cometa P/Halley sob a Ótica do Modelo de Reconexão Magnética

    NASA Astrophysics Data System (ADS)

    Voelzke, M. R.; Matsuura, O. T.

    1998-08-01

    531 imagens contidas no The International Halley Watch Atlas of Large-Scale Phenomena (Brandt et al., 1992) cobrindo o período de setembro de 1985 a julho de 1986 foram analisadas visando identificar, caracterizar as propriedades e correlacionar estruturas morfológicas da cauda de plasma do cometa P/Halley. A análise revelou 47 eventos de desconexão (DEs) (Niedner & Brandt, 1979; Jockers, 1985; Celnik et al., 1988; Delva et al., 1991). A análise completa de todas as imagens encontra-se publicada em Voelzke & Matsuura, 1998. A distribuição dos DEs na distância heliocêntrica apresenta um caráter bimodal possivelmente associado com a distribuição espacial das fronteiras de setor magnético do meio interplanetário. Os 47 DEs fotografados em 47 imagens distintas permitiram determinar 19 origens de DEs, ou seja, o instante em que supostamente o cometa cruzou a fronteira entre setores magnéticos do vento solar. Tais dados cometários foram comparados com dados do vento solar provenientes de medidas realizadas in situ pelas sondas IMP-8, ICE e PVO, que mediram a variação da velocidade do vento solar, da densidade e da pressão dinâmica durante o intervalo analisado. Os dados destas sondas espaciais em conjunto com os da sonda Vega 1 foram usados para determinar o tempo das passagens do lençol de corrente. Com base nos dados das sondas foram calculadas as coordenadas heliográficas retroativas do lençol de corrente na "superfície fonte" dos mapas sinóticos do campo magnético de Hoeksema, 1989. O cálculo retroativo é feito através de um modelo simples de expressão do vento solar com velocidade uniforme, sendo considerada a co-rotação da magnetosfera com o Sol. Este trabalho apresenta os resultados desta comparação e a análise cinemática da origem dos DEs, determinada sob a hipótese que o plasma desconectado de um dado DE afasta-se com velocidade constante do núcleo cometário (Voelzke & Matsuura, 1998) e compara esta análise com outras que determinam o tempo de desconexão a partir de um movimento linear constantemente acelerado (Yi et al., 1994). A velocidade de um DE para outro varia enormemente. - Brandt, J.C., Niedner, M.B.Jr. and Rahe, J., (1992) The International Halley Watch Atlas of Large-Scale Phenomena (printed by: Johnson Printing Co., Boulder, CO), University of Colorado-Boulder. - Celnik, W.E., Koczet, P., Schlosser, W., Schulz, R., Svejda, P. and Weissbauer, K., (1988) Astron. Astrophys. Suppl. Ser. 72, 89. - Delva, M., Schwingenschuh, K., Niedner, M.B.Jr. and Gringauz, K.I., (1991) Planet. Space Sci. 39, Number 5, 697. - Hoeksema, J.T., (1989) Adv. Space Res. 9, 141. - Jockers, K., (1985) Astron. Astrophys. Suppl. Ser. 62, 791. - Niedner, M.B.Jr. and Brandt, J.C., (1979) Astrophys. J. 234, 723. - Voelzke, M.R. and Matsuura, O.T., (1988) Planet. Space Sci. 46, 835. - Yi, Y., Caputo, M.F. and Brandt, J.C., (1994) Planet. Space Sci. 42, Number 9, 705.

  1. Multiprofissional electronic protocol in ophtalmology with enfasis in strabismus.

    PubMed

    Ribeiro, Christie Graf; Moreira, Ana Tereza Ramos; Pinto, José Simão DE Paula; Malafaia, Osvaldo

    2016-01-01

    to create and validate an electronic database in ophthalmology focused on strabismus, to computerize this database in the form of a systematic data collection software named Electronic Protocol, and to incorporate this protocol into the Integrated System of Electronic Protocols (SINPE(c)). this is a descriptive study, with the methodology divided into three phases: (1) development of a theoretical ophthalmologic database with emphasis on strabismus; (2) computerization of this theoretical ophthalmologic database using SINPE(c) and (3) interpretation of the information with demonstration of results to validate the protocol. We inputed data from the charts of fifty patients with known strabismus through the Electronic Protocol for testing and validation. the new electronic protocol was able to store information regarding patient history, physical examination, laboratory exams, imaging results, diagnosis and treatment of patients with ophthalmologic diseases, with emphasis on strabismus. We included 2,141 items in this master protocol and created 20 new specific electronic protocols for strabismus, each with its own specifics. Validation was achieved through correlation and corroboration of the symptoms and confirmed diagnoses of the fifty included patients with the diagnostic criteria for the twenty new strabismus protocols. a new, validated electronic database focusing on ophthalmology, with emphasis on strabismus, was successfully created through the standardized collection of information, and computerization of the database using proprietary software. This protocol is ready for deployment to facilitate data collection, sorting and application for practitioners and researchers in numerous specialties. criar uma base eletrônica de dados em oftalmologia com ênfase em estrabismo através da coleta padronizada de informações. Informatizar esta base sob a forma de software para a coleta sistemática de dados chamado "Protocolo Eletrônico" e incorporar este "Protocolo Eletrônico" da Oftalmologia ao Sistema Integrado de Protocolos Eletrônicos (SINPE(c)). este é um estudo descritivo e a metodologia aplicada em seu desenvolvimento está didaticamente dividida em três fases: 1) criação da base teórica de dados clínicos de oftalmologia com ênfase em estrabismo; 2) informatização da base teórica dos dados utilizando o SINPE(c); e 3) interpretação das informações com demonstração dos resultados. A informatização da base de dados foi realizada pela utilização da concessão de uso do SINPE(c). Foram incluídos neste protocolo 50 pacientes com estrabismo para validação do protocolo. o protocolo eletrônico desenvolvido permitiu armazenar informações relacionadas à anamnese, exame físico, exames complementares, diagnóstico e tratamento de pacientes com doenças oftalmológicas, com ênfase em estrabismo. Foram incluídos neste trabalho 2141 itens no protocolo mestre e foram criados 20 protocolos específicos de estrabismo, cada um com suas particularidades. Os 50 pacientes que foram incluídos nos protocolos específicos demonstraram a eficácia do método empregado. foi criada uma base eletrônica de dados em oftalmologia com ênfase em estrabismo através da coleta padronizada de informações. Esta base de dados foi informatizada sob a forma de software onde os futuros usuários poderão utilizar o protocolo eletrônico multiprofissional de doenças oftalmológicas com ênfase em estrabismo para a coleta de seus dados.

  2. Gastric wall changes after intragastric balloon placement: a preliminary experience.

    PubMed

    Périssé, Luís Gustavo Santos; Ecbc-Rj, Paulo Cézar Marques Périssé; Ribeiro, Kelson Ferreira

    2016-01-01

    : to evaluate the thickness of the gastric wall at the time of intra gastric balloon (IGB) placement, at the time of its withdrawal and one month after withdrawal. : fifteen morbidly obese patients underwent the introduction of IGB under general anesthesia. In all patients, there was infusion of 500ml of distilled water in the balloon for the test. Measurements of the thickness of the gastric wall were made in the antrum, body and proximal body, using a radial echoendoscope with a frequency of 12MHz and maximum zoom, and its own balloon inflated with 5ml of distilled water. : the presence of IGB led to increased wall thickness of the gastric body by expanding the muscle layer. These changes were apparently transient, since 30 days after the balloon withdrawal there was a tendency to return of the wall thickness values ​​observed before the balloon insertion. : the use of intragastric balloon for the treatment of obesity determines transient increase in the wall thickness of the gastric body caused by expanded muscle layer. avaliar a espessura da parede gástrica no momento do posicionamento do balão intragástrico (BIG), no momento de sua retirada e um mês após a retirada. quinze pacientes obesos mórbidos foram submetidos à introdução de BIG sob anestesia geral. Em todos os pacientes foi feita infusão de 500 ml de água destilada e o balão foi insuflado com 5ml de água destilada. As medidas da espessura da parede gástrica foram feitas no antro, corpo e corpo alto utilizando-se um ecoendoscópio radial com frequência de 12MHz e zoom máximo. a presença do BIG levou ao aumento da espessura da parede do corpo gástrico pelo aumento de espessura da sua camada muscular. Estas alterações são aparentemente transitórias já que após 30 dias da retirada do balão existiu uma tendência de retorno da espessura da parede aos valores observados antes do seu posicionamento. a utilização do balão intragástrico para tratamento da obesidade determina aumento transitório da espessura da parede do corpo gástrico causado pelo aumento da camada muscular.

  3. Sulfur-oxidizing bacterial populations within cyanobacterial dominated coral disease lesions.

    PubMed

    Bourne, David G; van der Zee, Marc J J; Botté, Emmanuelle S; Sato, Yui

    2013-08-01

    This study investigated the diversity and quantitative shifts of sulfur-oxidizing bacteria (SOB) during the onset of black band disease (BBD) in corals using quantitative PCR (qPCR) and cloning approaches targeting the soxB gene, involved in sulfur oxidation. Four Montipora sp. coral colonies identified with lesions previously termed cyanobacterial patches (CP) (comprising microbial communities different from those of BBD lesions), was monitored in situ as CP developed into BBD. The overall abundance of SOB in both CP and BBD lesions were very low and near the detection limit of the qPCR assay, although consistently indicated that SOB populations decreased as the lesions transitioned from CP to BBD. Phylogenetic assessment of retrieved soxB genes showed that SOB in both CP and BBD lesions were dominated by one sequence type, representing > 70% of all soxB gene sequences and affiliated with members of the Rhodobacteraceae within the α-Proteobacteria. This study represents the first assessment targeting SOB within BBD lesions and clearly shows that SOB are not highly diverse or abundant in this complex microbial mat. The lack of oxidation of reduced sulfur compounds by SOB likely aids the accumulation of high levels of sulfide at the base of the BBD mat, a compound contributing to the pathogenicity of BBD lesions. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

  4. Nursing workload for cancer patients under palliative care.

    PubMed

    Fuly, Patrícia Dos Santos Claro; Pires, Livia Márcia Vidal; Souza, Claudia Quinto Santos de; Oliveira, Beatriz Guitton Renaud Baptista de; Padilha, Katia Grillo

    2016-01-01

    To verify the nursing workload required by cancer patients undergoing palliative care and possible associations between the demographic and clinical characteristics of the patients and the nursing workload. This is a quantitative, cross-sectional, prospective study developed in the Connective Bone Tissue (TOC) clinics of Unit II of the Brazilian National Cancer Institute José Alencar Gomes da Silva with patients undergoing palliative care. Analysis of 197 measures of the Nursing Activities Score (NAS) revealed a mean score of 43.09% and an association between the performance status of patients undergoing palliative care and the mean NAS scores. The results of the study point to the need to resize the team of the unit. The NAS has proven to be a useful tool in oncologic clinical units for patients undergoing palliative care. Verificar a carga de trabalho de enfermagem requerida por pacientes com câncer sob cuidados paliativos e possíveis associações entre as características demográficas e clínicas dos pacientes e a carga de trabalho de enfermagem. Trata-se de um estudo de abordagem quantitativa, transversal, prospectivo, desenvolvido na clínica de Tecido Ósseo Conectivo (TOC) da Unidade II do Instituto Nacional de Câncer José Alencar Gomes da Silva, com pacientes em cuidados paliativos. A análise de 197 medidas do Nursing Activities Score (NAS) revelou um escore médio de 43,09% e uma associação entre a performance status de pacientes em cuidados paliativos com os valores médios do NAS. Os resultados do estudo apontam para a necessidade de redimensionamento da equipe da Unidade. O NAS mostrou-se um instrumento passível de utilização em unidades clínicas oncológicas, com pacientes em cuidados paliativos.

  5. Compositions and Abundances of Sulfate-Reducing and Sulfur-Oxidizing Microorganisms in Water-Flooded Petroleum Reservoirs with Different Temperatures in China

    PubMed Central

    Tian, Huimei; Gao, Peike; Chen, Zhaohui; Li, Yanshu; Li, Yan; Wang, Yansen; Zhou, Jiefang; Li, Guoqiang; Ma, Ting

    2017-01-01

    Sulfate-reducing bacteria (SRB) have been studied extensively in the petroleum industry due to their role in corrosion, but very little is known about sulfur-oxidizing bacteria (SOB), which drive the oxidization of sulfur-compounds produced by the activity of SRB in petroleum reservoirs. Here, we surveyed the community structure, diversity and abundance of SRB and SOB simultaneously based on 16S rRNA, dsrB and soxB gene sequencing, and quantitative PCR analyses, respectively in petroleum reservoirs with different physicochemical properties. Similar to SRB, SOB were found widely inhabiting the analyzed reservoirs with high diversity and different structures. The dominant SRB belonged to the classes Deltaproteobacteria and Clostridia, and included the Desulfotignum, Desulfotomaculum, Desulfovibrio, Desulfobulbus, and Desulfomicrobium genera. The most frequently detected potential SOB were Sulfurimonas, Thiobacillus, Thioclava, Thiohalomonas and Dechloromonas, and belonged to Betaproteobacteria, Alphaproteobacteria, and Epsilonproteobacteria. Among them, Desulfovibrio, Desulfomicrobium, Thioclava, and Sulfurimonas were highly abundant in the low-temperature reservoirs, while Desulfotomaculum, Desulfotignum, Thiobacillus, and Dechloromonas were more often present in high-temperature reservoirs. The relative abundances of SRB and SOB varied and were present at higher proportions in the relatively high-temperature reservoirs. Canonical correspondence analysis also revealed that the SRB and SOB communities in reservoirs displayed high niche specificity and were closely related to reservoir temperature, pH of the formation brine, and sulfate concentration. In conclusion, this study extends our knowledge about the distribution of SRB and SOB communities in petroleum reservoirs. PMID:28210252

  6. Assessment of the stoichiometry and efficiency of CO2 fixation coupled to reduced sulfur oxidation

    PubMed Central

    Klatt, Judith M.; Polerecky, Lubos

    2015-01-01

    Chemolithoautotrophic sulfur oxidizing bacteria (SOB) couple the oxidation of reduced sulfur compounds to the production of biomass. Their role in the cycling of carbon, sulfur, oxygen, and nitrogen is, however, difficult to quantify due to the complexity of sulfur oxidation pathways. We describe a generic theoretical framework for linking the stoichiometry and energy conservation efficiency of autotrophic sulfur oxidation while accounting for the partitioning of the reduced sulfur pool between the energy generating and energy conserving steps as well as between the main possible products (sulfate vs. zero-valent sulfur). Using this framework, we show that the energy conservation efficiency varies widely among SOB with no apparent relationship to their phylogeny. Aerobic SOB equipped with reverse dissimilatory sulfite reductase tend to have higher efficiency than those relying on the complete Sox pathway, whereas for anaerobic SOB the presence of membrane-bound, as opposed to periplasmic, nitrate reductase systems appears to be linked to higher efficiency. We employ the framework to also show how limited rate measurements can be used to estimate the primary productivity of SOB without the knowledge of the sulfate-to-zero-valent-sulfur production ratio. Finally, we discuss how the framework can help researchers gain new insights into the activity of SOB and their niches. PMID:26052315

  7. Season of Birth and Dopamine Receptor Gene Associations with Impulsivity, Sensation Seeking and Reproductive Behaviors

    PubMed Central

    Eisenberg, Dan T. A.; Campbell, Benjamin; MacKillop, James; Lum, J. Koji; Wilson, David S.

    2007-01-01

    Background Season of birth (SOB) has been associated with many physiological and psychological traits including novelty seeking and sensation seeking. Similar traits have been associated with genetic polymorphisms in the dopamine system. SOB and dopamine receptor genetic polymorphisms may independently and interactively influence similar behaviors through their common effects on the dopaminergic system. Methodology/Principal Findings Based on a sample of 195 subjects, we examined whether SOB was associated with impulsivity, sensation seeking and reproductive behaviors. Additionally we examined potential interactions of dopamine receptor genes with SOB for the same set of traits. Phenotypes were evaluated using the Sociosexual Orientation Inventory, the Barratt Impulsivity Scale, the Eysenck Impulsivity Questionnaire, the Sensation Seeking Scale, and the Delay Discounting Task. Subjects were also asked about their age at first sex as well as their desired age at the birth of their first child. The dopamine gene polymorphisms examined were Dopamine Receptor D2 (DRD2) TaqI A and D4 (DRD4) 48 bp VNTR. Primary analyses included factorial gender×SOB ANOVAs or binary logistic regression models for each dependent trait. Secondary analysis extended the factorial models by also including DRD2 and DRD4 genotypes as independent variables. Winter-born males were more sensation seeking than non-winter born males. In factorial models including both genotype and season of birth as variables, two previously unobserved effects were discovered: (1) a SOB×DRD4 interaction effect on venturesomeness and (2) a DRD2×DRD4 interaction effect on sensation seeking. Conclusion These results are consistent with past findings that SOB is related to sensation seeking. Additionally, these results provide tentative support for the hypothesis that SOB modifies the behavioral expression of dopaminergic genetic polymorphism. These findings suggest that SOB should be included in future studies of risky behaviors and behavioral genetic studies of the dopamine system. PMID:18030347

  8. (Un)receptiveness in interactions with professionals: experiences of parents of children with retinopathy of prematurity.

    PubMed

    Facio, Beatriz Castanheira; Marski, Bruna de Souza Lima; Higarashi, Ieda Harumi; Misko, Maira Deguer; Silveira, Aline Oliveira; Wernet, Monika

    2016-01-01

    To analyze the influence of health professionals' receptiveness on parental care of children with retinopathy of prematurity (ROP). A qualitative study developed under the theoretical framework of Symbolic Interactionism and using a narrative research methodology. Six women and three men, being parents of children with retinopathy of prematurity were individually interviewed in depth. From the scope of information, emotions and their rights, the parents experienced receptiveness from some professionals and unreceptiveness from others. The predominance of unreceptive attitudes in the parental narratives originated the following analysis themes: Informational (un)receptiveness, Emotional (un)receptiveness, and (Un)receptiveness of rights. The study supports human and comprehensive healthcare in the context of retinopathy of prematurity by pointing out the interactive process with health professionals as a potential stressor of parental care. The results signal a nuclear of attitudinal changes and reinforce challenges to the child and family-centered approach. Analisar a influência do acolhimento do profissional de saúde no cuidado parental junto ao filho com retinopatia da prematuridade. Estudo qualitativo desenvolvido sob o referencial teórico do Interacionismo Simbólico e metodológico da pesquisa de narrativas. Foram entrevistados em profundidade e individualmente seis mulheres e três homens, pais de crianças com retinopatia da prematuridade. Os pais vivenciam, nos âmbitos informacional, emocional e de direitos, acolhimento com alguns profissionais e destrato com outros. A predominância da postura de desacolhimento nas narrativas parentais deu origem aos temas de análise: (Des)acolhimento informacional, (Des)acolhimento emocional, e (Des)acolhimento de direitos. O estudo oferece subsídios ao cuidado humano e integral em saúde no contexto da retinopatia da prematuridade ao apontar o processo interativo com os profissionais de saúde enquanto potencial estressor do cuidado parental. Os resultados sinalizam núcleos de mudanças atitudinais e reforçam desafios à abordagem centrada na criança e família.

  9. Comparison of the Structure and Expression of Odd-Skipped and Two Related Genes That Encode a New Family of Zinc Finger Proteins in Drosophila

    PubMed Central

    Hart, M. C.; Wang, L.; Coulter, D. E.

    1996-01-01

    The odd-skipped (odd) gene, which was identified on the basis of a pair-rule segmentation phenotype in mutant embryos, is initially expressed in the Drosophila embryo in seven pair-rule stripes, but later exhibits a segment polarity-like pattern for which no phenotypic correlate is apparent. We have molecularly characterized two embryonically expressed odd-cognate genes, sob and bowel (bowl), that encode proteins with highly conserved C(2)H(2) zinc fingers. While the Sob and Bowl proteins each contain five tandem fingers, the Odd protein lacks a fifth (C-terminal) finger and is also less conserved among the four common fingers. Reminiscent of many segmentation gene paralogues, the closely linked odd and sob genes are expressed during embryogenesis in similar striped patterns; in contrast, the less-tightly linked bowl gene is expressed in a distinctly different pattern at the termini of the early embryo. Although our results indicate that odd and sob are more likely than bowl to share overlapping developmental roles, some functional divergence between the Odd and Sob proteins is suggested by the absence of homology outside the zinc fingers, and also by amino acid substitutions in the Odd zinc fingers at positions that appear to be constrained in Sob and Bowl. PMID:8878683

  10. Links between sulphur oxidation and sulphur-oxidising bacteria abundance and diversity in soil microcosms based on soxB functional gene analysis.

    PubMed

    Tourna, Maria; Maclean, Paul; Condron, Leo; O'Callaghan, Maureen; Wakelin, Steven A

    2014-06-01

    Sulphur-oxidising bacteria (SOB) play a key role in the biogeochemical cycling of sulphur in soil ecosystems. However, the ecology of SOB is poorly understood, and there is little knowledge about the taxa capable of sulphur oxidation, their distribution, habitat preferences and ecophysiology. Furthermore, as yet there are no conclusive links between SOB community size or structure and rates of sulphur oxidation. We have developed a molecular approach based on primer design targeting the soxB functional gene of nonfilamentous chemolithotrophic SOB that allows assessment of both abundance and diversity. Cloning and sequencing revealed considerable diversity of known soxB genotypes from agricultural soils and also evidence for previously undescribed taxa. In a microcosm experiment, abundance of soxB genes increased with sulphur oxidation rate in soils amended with elemental sulphur. Addition of elemental sulphur to soil had a significant effect in the soxB gene diversity, with the chemolithotrophic Thiobacillus-like Betaproteobacteria sequences dominating clone libraries 6 days after sulphur application. Using culture-independent methodology, the study provides evidence for links between abundance and diversity of SOB and sulphur oxidation. The methodology provides a new tool for investigation of the ecology and role of SOB in soil sulphur biogeochemistry. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  11. Genomic analysis reveals versatile heterotrophic capacity of a potentially symbiotic sulfur-oxidizing bacterium in sponge.

    PubMed

    Tian, Ren-Mao; Wang, Yong; Bougouffa, Salim; Gao, Zhao-Ming; Cai, Lin; Bajic, Vladimir; Qian, Pei-Yuan

    2014-11-01

    Sulfur-reducing bacteria (SRB) and sulfur-oxidizing bacteria (SOB) play essential roles in marine sponges. However, the detailed characteristics and physiology of the bacteria are largely unknown. Here, we present and analyse the first genome of sponge-associated SOB using a recently developed metagenomic binning strategy. The loss of transposase and virulence-associated genes and the maintenance of the ancient polyphosphate glucokinase gene suggested a stabilized SOB genome that might have coevolved with the ancient host during establishment of their association. Exclusive distribution in sponge, bacterial detoxification for the host (sulfide oxidation) and the enrichment for symbiotic characteristics (genes-encoding ankyrin) in the SOB genome supported the bacterial role as an intercellular symbiont. Despite possessing complete autotrophic sulfur oxidation pathways, the bacterium developed a much more versatile capacity for carbohydrate uptake and metabolism, in comparison with its closest relatives (Thioalkalivibrio) and to other representative autotrophs from the same order (Chromatiales). The ability to perform both autotrophic and heterotrophic metabolism likely results from the unstable supply of reduced sulfur in the sponge and is considered critical for the sponge-SOB consortium. Our study provides insights into SOB of sponge-specific clade with thioautotrophic and versatile heterotrophic metabolism relevant to its roles in the micro-environment of the sponge body. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  12. Major amputation of lower extremity: prognostic value of positive bone biopsy cultures.

    PubMed

    Vaznaisiene, D; Beltrand, E; Laiskonis, A P; Yazdanpanah, Y; Migaud, H; Senneville, E

    2013-02-01

    To assess the correlation between culture results of section's osseous slice biopsy (SOB) and the distal infected site responsible for the amputation performed concomitantly during major amputation of lower extremity. The influence of a positive culture of SOB on the patients' outcome was also evaluated. We conducted a retrospective study of medical charts of patients who underwent SOB during major amputation of lower extremity at our institution from 2000 to 2009. Fifty-seven patients (42 males/15 females, mean age 52.16years) who undergone major limb amputation (47 below knee and ten above knee) were included. The initial medical conditions of the investigated patients were: trauma (n=32), infection (n=13), trophic disorders (n=10) and tumor (n=2). The major cause of amputation was an uncontrolled infection, accouting for 64.9% of the cases (37/57) (foot=5, ankle=8, leg=24), the remaining 20 patients had trophic disorders of lower limb. Twenty-one (36.8%) from 57 biopsies were sterile, 12 (21.1%) doubtful and 24 (42.1%) positive. Thirty-one (54.4%) patients had an antibiotic-free interval before limb amputation. Independently of the bacterial species, 69.6% of the microorganisms identified from SOB were found in the distal infected site. Patients with positive SOB had a significantly longer interval between the decision to amputate the patient and the surgical procedure (200.2 vs. 70.1days; P<0.03) and a shorter total duration of antibiotic therapy before amputation than patients with negative SOB (3.68 vs. 6.08months; P<0.03). The delay for complete healing was significantly higher in patients with a positive SOB compared with those with a negative SOB (3.57 vs. 2.48months; P<0.03). Our results suggest that the infection may extend from the distal site to the level of amputation in a large proportion of cases and that the delay with which the amputation is performed after the decision has been taken may play a role in this event. Study level IV: retrospective observationnal study. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  13. Society Girl, Sob Sister, Journalism Educator: Mary Paxton Keeley, the First Woman Graduate of the School of Journalism at the University of Missouri.

    ERIC Educational Resources Information Center

    Zang, Barbara

    Based on an examination of well-kept primary source material, this paper presents a personal and professional history of Mary Paxton Keeley, the first woman graduate of one of the first journalism schools in the United States, the School of Journalism at the University of Missouri. Starting with her early years, the paper explains that Keeley was…

  14. The efficacy of N-acetylcysteine plus sodium bicarbonate in the prevention of contrast-induced nephropathy after cardiac catheterization and percutaneous coronary intervention: A meta-analysis of randomized controlled trials.

    PubMed

    Zhao, Shi-Jie; Zhong, Zhao-Shuang; Qi, Guo-Xian; Tian, Wen

    2016-10-15

    The efficacy of combining use of N-acetylcysteine (NAC) and sodium bicarbonate (SOB) in the prevention of contrast-induced nephropathy (CIN) after cardiac catheterization and percutaneous coronary intervention (PCI) is unclear. All relevant studies that compared the effect of combining the use of NAC and SOB with individual use on CIN in patients undergoing cardiac catheterization and PCI were identified by searching the databases including Pubmed, Embase, Cochrane Library, and Web of Science without time and language limitation. Only randomized controlled trials (RCTs) with full-text published were considered. Sixteen RCTs involving 4432 cases were included into this meta-analysis. The results showed there were no additional benefit in reduction of CIN in COM group (COM versus NAC: RR 0.85, 95% CI 0.70-1.03, P=0.103; COM versus SOB: RR 0.91, 95% CI 0.71-1.16, P=0.449), even in patients with diabetes mellitus (COM versus NAC: RR 1.11, 95% CI 0.71-1.75, P=0.646; COM versus SOB: RR 1.06, 95% CI 0.45-2.47, P=0.893), undergoing PCI procedure (COM versus NAC: RR0.76, 95% CI 0.39-1.47, P=0.411; COM versus SOB: RR0.96, 95% CI 0.65-1.40, P=0.814), or with baseline renal dysfunction (COM versus NAC: RR 0.89, 95% CI 0.70-1.14, P=0.366; COM versus SOB: RR 0.95, 95% CI 0.67-1.36, P=0.788). The present study demonstrated combining use of NAC and SOB was not significantly superior to individual use method in the prevention of CIN after cardiac catheterization and PCI. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Succession of Sulfur-Oxidizing Bacteria in the Microbial Community on Corroding Concrete in Sewer Systems† ▿

    PubMed Central

    Okabe, Satoshi; Odagiri, Mitsunori; Ito, Tsukasa; Satoh, Hisashi

    2007-01-01

    Microbially induced concrete corrosion (MICC) in sewer systems has been a serious problem for a long time. A better understanding of the succession of microbial community members responsible for the production of sulfuric acid is essential for the efficient control of MICC. In this study, the succession of sulfur-oxidizing bacteria (SOB) in the bacterial community on corroding concrete in a sewer system in situ was investigated over 1 year by culture-independent 16S rRNA gene-based molecular techniques. Results revealed that at least six phylotypes of SOB species were involved in the MICC process, and the predominant SOB species shifted in the following order: Thiothrix sp., Thiobacillus plumbophilus, Thiomonas intermedia, Halothiobacillus neapolitanus, Acidiphilium acidophilum, and Acidithiobacillus thiooxidans. A. thiooxidans, a hyperacidophilic SOB, was the most dominant (accounting for 70% of EUB338-mixed probe-hybridized cells) in the heavily corroded concrete after 1 year. This succession of SOB species could be dependent on the pH of the concrete surface as well as on trophic properties (e.g., autotrophic or mixotrophic) and on the ability of the SOB to utilize different sulfur compounds (e.g., H2S, S0, and S2O32−). In addition, diverse heterotrophic bacterial species (e.g., halo-tolerant, neutrophilic, and acidophilic bacteria) were associated with these SOB. The microbial succession of these microorganisms was involved in the colonization of the concrete and the production of sulfuric acid. Furthermore, the vertical distribution of microbial community members revealed that A. thiooxidans was the most dominant throughout the heavily corroded concrete (gypsum) layer and that A. thiooxidans was most abundant at the highest surface (1.5-mm) layer and decreased logarithmically with depth because of oxygen and H2S transport limitations. This suggested that the production of sulfuric acid by A. thiooxidans occurred mainly on the concrete surface and the sulfuric acid produced penetrated through the corroded concrete layer and reacted with the sound concrete below. PMID:17142362

  16. Microbial community structures and in situ sulfate-reducing and sulfur-oxidizing activities in biofilms developed on mortar specimens in a corroded sewer system.

    PubMed

    Satoh, Hisashi; Odagiri, Mitsunori; Ito, Tsukasa; Okabe, Satoshi

    2009-10-01

    Microbially induced concrete corrosion (MICC) caused by sulfuric acid attack in sewer systems has been a serious problem for a long time. A better understanding of microbial community structures of sulfate-reducing bacteria (SRB) and sulfur-oxidizing bacteria (SOB) and their in situ activities is essential for the efficient control of MICC. In this study, the microbial community structures and the in situ hydrogen sulfide production and consumption rates within biofilms and corroded materials developed on mortar specimens placed in a corroded manhole was investigated by culture-independent 16S rRNA gene-based molecular techniques and microsensors for hydrogen sulfide, oxygen, pH and the oxidation-reduction potential. The dark-gray gel-like biofilm was developed in the bottom (from the bottom to 4 cm) and the middle (4-20 cm from the bottom of the manhole) parts of the mortar specimens. White filamentous biofilms covered the gel-like biofilm in the middle part. The mortar specimens placed in the upper part (30 cm above the bottom of the manhole) were corroded. The 16S rRNA gene-cloning analysis revealed that one clone retrieved from the bottom biofilm sample was related to an SRB, 12 clones and 6 clones retrieved from the middle biofilm and the corroded material samples, respectively, were related to SOB. In situ hybridization results showed that the SRB were detected throughout the bottom biofilm and filamentous SOB cells were mainly detected in the upper oxic layer of the middle biofilm. Microsensor measurements demonstrated that hydrogen sulfide was produced in and diffused out of the bottom biofilms. In contrast, in the middle biofilm the hydrogen sulfide produced in the deeper parts of the biofilm was oxidized in the upper filamentous biofilm. pH was around 3 in the corroded materials developed in the upper part of the mortar specimens. Therefore, it can be concluded that hydrogen sulfide provided from the bottom biofilms and the sludge settling tank was emitted to the sewer atmosphere, then oxidized to corrosive compounds in the upper and middle parts of the manhole, and only the upper part of the mortar specimens were corroded, because in the middle part of the manhole the generated corrosive compounds (e.g., sulfuric acid) was reduced in the deeper parts of the biofilm.

  17. Staging dementia using Clinical Dementia Rating Scale Sum of Boxes scores: a Texas Alzheimer's research consortium study.

    PubMed

    O'Bryant, Sid E; Waring, Stephen C; Cullum, C Munro; Hall, James; Lacritz, Laura; Massman, Paul J; Lupo, Philip J; Reisch, Joan S; Doody, Rachelle

    2008-08-01

    The Clinical Dementia Rating Scale Sum of Boxes (CDR-SOB) score is commonly used, although the utility regarding this score in staging dementia severity is not well established. To investigate the effectiveness of CDR-SOB scores in staging dementia severity compared with the global CDR score. Retrospective study. Texas Alzheimer's Research Consortium minimum data set cohort. A total of 1577 participants (110 controls, 202 patients with mild cognitive impairment, and 1265 patients with probable Alzheimer disease) were available for analysis. Receiver operating characteristic curves were generated from a derivation sample to determine optimal cutoff scores and ranges, which were then applied to the validation sample. Optimal ranges of CDR-SOB scores corresponding to the global CDR scores were 0.5 to 4.0 for a global score of 0.5, 4.5 to 9.0 for a global score of 1.0, 9.5 to 15.5 for a global score of 2.0, and 16.0 to 18.0 for a global score of 3.0. When applied to the validation sample, kappa scores ranged from 0.86 to 0.94 (P < .001 for all), with 93.0% of the participants falling within the new staging categories. The CDR-SOB score compares well with the global CDR score for dementia staging. Owing to the increased range of values, the CDR-SOB score offers several advantages over the global score, including increased utility in tracking changes within and between stages of dementia severity. Interpretive guidelines for CDR-SOB scores are provided.

  18. The association of clinical indication for exercise stress testing with all-cause mortality: the FIT Project

    PubMed Central

    Kim, Joonseok; Al-Mallah, Mouaz; Juraschek, Stephen P.; Brawner, Clinton; Keteyian, Steve J.; Nasir, Khurram; Dardari, Zeina A.; Blumenthal, Roger S.

    2016-01-01

    Introduction We hypothesized that the indication for stress testing provided by the referring physician would be an independent predictor of all-cause mortality. Material and methods We studied 48,914 patients from The Henry Ford Exercise Testing Project (The FIT Project) without known congestive heart failure who were referred for a clinical treadmill stress test and followed for 11 ±4.7 years. The reason for stress test referral was abstracted from the clinical test order, and should be considered the primary concerning symptom or indication as stated by the ordering clinician. Hierarchical multivariable Cox proportional hazards regression was performed, after controlling for potential confounders including demographics, risk factors, and medication use as well as additional adjustment for exercise capacity in the final model. Results A total of 67% of the patients were referred for chest pain, 12% for shortness of breath (SOB), 4% for palpitations, 3% for pre-operative evaluation, 6% for abnormal prior testing, and 7% for risk factors only. There were 6,211 total deaths during follow-up. Compared to chest pain, those referred for palpitations (HR = 0.72, 95% CI: 0.60–0.86) and risk factors only (HR = 0.72, 95% CI: 0.63–0.82) had a lower risk of all-cause mortality, whereas those referred for SOB (HR = 1.15, 95% CI: 1.07–1.23) and pre-operative evaluation (HR = 2.11, 95% CI: 1.94–2.30) had an increased risk. In subgroup analysis, referral for palpitations was protective only in those without coronary artery disease (CAD) (HR = 0.75, 95% CI: 0.62–0.90), while SOB increased mortality risk only in those with established CAD (HR = 1.25, 95% CI: 1.10–1.44). Conclusions The indication for stress testing is an independent predictor of mortality, showing an interaction with CAD status. Importantly, SOB may be associated with higher mortality risk than chest pain, particularly in patients with CAD. PMID:27186173

  19. Evaluation in health: participatory methodology and involvement of municipal managers.

    PubMed

    Almeida, Cristiane Andrea Locatelli de; Tanaka, Oswaldo Yoshimi

    2016-08-04

    To analyze scopes and limits of the use of participatory methodology of evaluation with municipal health managers and administrators. Qualitative research with health policymakers and managers of the Comissão Intergestores Regional (CIR - Regional Interagency Commission) of a health region of the state of Sao Paulo in Brazil. Representatives from seven member cities participated in seven workshops facilitated by the researchers, with the aim of assessing a specific problem of the care line, which would be used as a tracer of the system integrality. The analysis of the collected empirical material was based on the hermeneutic-dialectic methodology and aimed at the evaluation of the applied participatory methodology, according to its capacity of promoting a process of assessment capable to be used as a support for municipal management. With the participatory approach of evaluation, we were able to promote in-depth discussions with the group, especially related to the construction of integral care and to the inclusion of the user's perspective in decision-making, linked to the search for solution to concrete problems of managers. By joint exploration, the possibility of using data from electronic information systems was opened, as well as information coming directly from the users of the services, to enhance discussions and negotiations between partners. The participants were disbelievers of the replication potential of this type of evaluation without the direct monitoring of the academy, given the difficulty of organizing the process in everyday life, already taken by emergency and political issues. Evaluations of programs and services carried out within the Regional Interagency Commission, starting from the local interest and facilitating the involvement of its members by the use of participatory methodologies, can contribute to the construction of integral care. To the extent that the act of evaluating stay invested with greater significance to the local actors, its involvement with the evaluations at the federal level can also be stimulated. Analisar alcances e limites do uso de metodologia participativa de avaliação junto a gestores e gerentes municipais de saúde. Pesquisa qualitativa com gestores e gerentes de saúde da Comissão Intergestores Regional de uma região de saúde do estado de São Paulo. Representantes de sete municípios membros participaram de sete oficinas facilitadas pelos pesquisadores, com o objetivo de avaliar um problema específico da linha de cuidados sob a perspectiva da integralidade. A análise do material empírico coletado baseou-se na metodologia hermenêutica-dialética e visou a avaliação da metodologia participativa aplicada, segundo sua capacidade de promover um processo de avaliação passível de ser utilizado como suporte à gestão municipal. Com a abordagem participativa de avaliação, foi possível promover debates em profundidade com o grupo, principalmente relacionados à construção da integralidade da atenção e à inclusão da perspectiva do usuário na tomada de decisão, de forma vinculada à busca de solução para problemas concretos dos gestores. Mediante a exploração conjunta, foi aberta a possibilidade de utilização de dados advindos dos sistemas eletrônicos de informação, bem como de informações advindas diretamente dos usuários dos serviços, para enriquecer debates e negociações entre parceiros. Os participantes se mostraram descrentes do potencial de replicação deste tipo de avaliação sem o acompanhamento direto da academia, dada a dificuldade de organização do processo no cotidiano, já tomado por questões emergenciais e políticas. Avaliações de programas e serviços realizadas no âmbito da Comissão Intergestores Regional, partindo do interesse local e facilitando o envolvimento de seus membros pelo uso de metodologias participativas, podem contribuir para a construção da integralidade do cuidado. Na medida em que o ato de avaliar fique investido de maior significado para os atores locais, seu envolvimento com as avaliações em nível federal poderá ser também estimulado.

  20. A new role for the Arabidopsis AP2 transcription factor, LEAFY PETIOLE, in gibberellin-induced germination is revealed by the misexpression of a homologous gene, SOB2/DRN-LIKE.

    PubMed

    Ward, Jason M; Smith, Alison M; Shah, Purvi K; Galanti, Sarah E; Yi, Hankuil; Demianski, Agnes J; van der Graaff, Eric; Keller, Beat; Neff, Michael M

    2006-01-01

    Gibberellic acid (GA) promotes germination, stem/hypocotyl elongation, and leaf expansion during seedling development. Using activation-tagging mutagenesis, we identified a mutation, sob2-D (for suppressor of phytochromeB-4 [phyB-4]#2 dominant), which suppresses the long-hypocotyl phenotype of a phyB missense allele, phyB-4. This mutant phenotype is caused by the overexpression of an APETALA2 transcription factor, SOB2, also called DRN-like. SOB2/DRN-like transcript is not detectable in wild-type seedling or adult tissues via RT-PCR analysis, suggesting that SOB2/DRN-like may not be involved in seedling development under normal conditions. Adult sob2-D phyB-4 plants have curled leaves and club-like siliques, resembling plants that overexpress a closely related gene, LEAFY PETIOLE (LEP). Hypocotyls of a LEP-null allele, lep-1, are shorter in the light and dark, suggesting LEP involvement in seedling development. This aberrant hypocotyl phenotype is due at least in part to a delay in germination. In addition, lep-1 is less responsive to GA and more sensitive to the GA biosynthesis inhibitor paclobutrazol, indicating that LEP is a positive regulator of GA-induced germination. RT-PCR shows that LEP transcript accumulates in wild-type seeds during imbibition and germination, and the transcript levels of REPRESSOR OF ga1-3-LIKE2 (RGL2), a negative regulator of GA signaling during germination, is unaffected in lep-1. These results suggest LEP is a positive regulator of GA-induced germination acting independently of RGL2. An alternative model places LEP downstream of RGL2 in the GA-signaling cascade.

  1. Curva de rotação óptica de ESO-LV 5100550

    NASA Astrophysics Data System (ADS)

    Carvalho, D. B.; Soares, D. S. L.

    2003-08-01

    ESO-LV 5100550 é o membro mais fraco do par de galáxias austral SBG 357 (Soares et al. 1995). É classificada no catálogo RC3 como uma espiral ordinária de tipo inicial (early-type); porém, uma análise morfológica sugere que ela tenha uma grande barra. O objetivo do estudo é determinar sua cinemática de tal modo que possamos inferir mais a respeito de sua dinâmica, provavelmente perturbada, já que se espera que esteja sob forte influência da companheira ESO-LV 5100560. Apresentarei resultados parciais determinados a partir de espectros obtidos com o instrumento Double Spectrograph montado no telescópio Hale do Monte Palomar, EUA. As observações foram realizadas por D.S.L. Soares, P.M.V. Veiga e T.E. Nordgren, em 1998. Foram tomados espectros de fenda longa posicionada sobre a linha dos nodos do disco e ao longo da suposta barra. Os dados foram reduzidos com uso do pacote IRAF. Obtivemos o perfil de velocidades radiais na linha de visada ao longo das fendas e calculamos o desvio para o vermelho cosmológico do sistema, com base no espectro central. Determinamos as curvas de rotação deprojetadas, com base em cálculos para os valores teóricos esperados das componentes de velocidades puramente circulares em um disco inclinado. A inclinação do disco, dado fundamental nesta deprojeção, foi estimada através da média das elipticidades das isofotas mais externas.

  2. Effects of plant downtime on the microbial community composition in the highly saline brine of a geothermal plant in the North German Basin.

    PubMed

    Westphal, Anke; Lerm, Stephanie; Miethling-Graff, Rona; Seibt, Andrea; Wolfgramm, Markus; Würdemann, Hilke

    2016-04-01

    The microbial biocenosis in highly saline fluids produced from the cold well of a deep geothermal heat store located in the North German Basin was characterized during regular plant operation and immediately after plant downtime phases. Genetic fingerprinting revealed the dominance of sulfate-reducing bacteria (SRB) and fermentative Halanaerobiaceae during regular plant operation, whereas after shutdown phases, sequences of sulfur-oxidizing bacteria (SOB) were also detected. The detection of SOB indicated oxygen ingress into the well during the downtime phase. High 16S ribosomal RNA (rRNA) and dsrA gene copy numbers at the beginning of the restart process showed an enrichment of bacteria, SRB, and SOB during stagnant conditions consistent with higher concentrations of dissolved organic carbon (DOC), sulfate, and hydrogen sulfide in the produced fluids. The interaction of SRB and SOB during plant downtimes might have enhanced the corrosion processes occurring in the well. It was shown that scale content of fluids was significantly increased after stagnant phases. Moreover, the sulfur isotopic signature of the mineral scales indicated microbial influence on scale formation.

  3. Brain derived neurotrophic factor gene (BDNF) and personality traits: the modifying effect of season of birth and sex.

    PubMed

    Kazantseva, A; Gaysina, D; Kutlumbetova, Yu; Kanzafarova, R; Malykh, S; Lobaskova, M; Khusnutdinova, E

    2015-01-02

    Personality traits are complex phenotypes influenced by interactions of multiple genetic variants of small effect and environmental factors. It has been suggested that the brain derived neurotrophic factor gene (BDNF) is involved in personality traits. Season of birth (SOB) has also been shown to affect personality traits due to its influences on brain development during prenatal and early postnatal periods. The present study aimed to investigate the effects of BDNF on personality traits; and the modifying effects of SOB and sex on associations between BDNF and personality traits. A sample of 1018 young adults (68% women; age range 17-25years) of Caucasian origin from the Russian Federation was assessed on personality traits (Novelty Seeking, Harm Avoidance, Reward Dependence, Persistence, Self-directedness, Cooperativeness, Self-transcendence) with the Temperament and Character Inventory-125 (TCI-125). Associations between personality traits and 12 BDNF SNPs were tested using linear regression models. The present study demonstrated the effect of rs11030102 on Persistence in females only (PFDR=0.043; r(2)=1.3%). There were significant interaction effects between Val66Met (rs6265) and SOB (PFDR=0.048, r(2)=1.4%), and between rs2030323 and SOB (PFDR=0.042, r(2)=1.3%), on Harm Avoidance. Our findings provide evidence for the modifying effect of SOB on the association between BDNF and Harm Avoidance, and for the modifying effect of sex on the association between BDNF and Persistence. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Sobetirome and its Amide Prodrug Sob-AM2 Exert Thyromimetic Actions in Mct8-Deficient Brain.

    PubMed

    Bárez-López, Soledad; Hartley, Meredith D; Grijota-Martínez, Carmen; Scanlan, Thomas S; Guadaño-Ferraz, Ana

    2018-06-29

    Loss of function mutations in the thyroid hormone (TH)-specific cell membrane transporter, the monocarboxylate transporter 8 (MCT8), lead to profound psychomotor retardation and abnormal TH serum levels, with low thyroxine (T4) and high triiodothyronine (T3). Several studies point to impaired TH transport across brain barriers as a crucial pathophysiological mechanism resulting in cerebral hypothyroidism. Treatment options for MCT8-deficient patients are limited and are focused on overcoming the brain barriers. The aim of this study was to evaluate the ability of the TH analog sobetirome and its prodrug Sob-AM2 to access the brain and exert thyromimetic actions in the absence of Mct8. Juvenile wild-type (Wt) mice and mice lacking Mct8 and deiodinase type 2 (Mct8/Dio2KO) were treated systemically with daily injections of vehicle, 1 mg of sobetirome/kg body weight/day, or 0.3 mg of Sob-AM2/kg body weight/day for seven days. Sobetirome content was measured using liquid chromatography-tandem mass spectrometry, and T4 and T3 levels by specific radioimmunoassays. The effect of sobetirome treatment in the expression of T3-dependent genes was measured in the heart, liver, and cerebral cortex by real-time polymerase chain reaction. Sob-AM2 treatment in Mct8/Dio2KO animals led to 1.8-fold more sobetirome content in the brain and 2.5-fold less in plasma in comparison to the treatment with the parent drug sobetirome. Both sobetirome and Sob-AM2 treatments in Mct8/Dio2KO mice greatly decreased plasma T4 and T3 levels. Dio1 and Ucp2 gene expression was altered in the liver of Mct8/Dio2KO mice and was not affected by the treatments. In the heart, Hcn2 but not Atp2a2 expression was increased after treatment with the analogs. Interestingly, both sobetirome and Sob-AM2 treatments increased the expression of several T3-dependent genes in the brain such as Hr, Abcd2, Mme, and Flywch2 in Mct8/Dio2KO mice. Sobetirome and its amide prodrug Sob-AM2 can access the brain in the absence of Mct8 and exert thyromimetic actions modulating the expression of T3-dependent genes. At the peripheral level, the administration of these TH analogs results in the depletion of circulating T4 and T3. Therefore, sobetirome and Sob-AM2 have the potential to address the cerebral hypothyroidism and the peripheral hyperthyroidism characteristic of MCT8 deficiency.

  5. Data of heavy metals biosorption onto Sargassum oligocystum collected from the northern coast of Persian Gulf.

    PubMed

    Delshab, Sedigheh; Kouhgardi, Esmaeil; Ramavandi, Bahman

    2016-09-01

    This data article presents a simple method for providing a biosorbent from Sargassum oligocystum harvested from the northern coast of Persian Gulf, Bushehr, Iran. The characterization data of Sargassum oligocystum biochar (SOB) were analyzed using various instrumental techniques (FTIR and XPS). The kinetics, isotherms, and thermodynamics data of Hg(2+), Cd(2+), and Cu(2+) ions onto SOB were presented. The maximum biosorption capacity of SOB to uptake Hg(2+), Cd(2+), and Cu(2+) ions from aqueous solution was obtained 60.25, 153.85, and 45.25 mg/g, respectively. The experimental data showed that biochar prepared from Sargassum oligocystum is an efficient and promising biosorbent for the treatment of heavy metals-bearing wastewaters.

  6. The Douro estuarine plume: Detection, processes and dynamics =

    NASA Astrophysics Data System (ADS)

    Mendes, Renato Paulo dos Santos

    O Douro e um dos maiores rios da Peninsula Iberica, constituindo a maior descarga de agua doce para o Oceano Atlântico na costa noroeste portuguesa. A sua pluma estuarina tem particular relevância na dinâmica costeira e na modulacao de fenomenos biogeoquimicos. Sao objetivos desta dissertacao contribuir para a compreensao dos processos fisicos associados a geracao e propagacao da pluma estuarina do Rio Douro no oceano, assim como para o conhecimento dos seus padroes de dispersao e da forma como estes alteram a hidrologia e a circulacao costeira, considerando os agentes forcadores tipicos deste fenomeno (caudal fluvial, vento e mare) e indices climaticos relevantes. Para concretizacao destes objetivos foram desenvolvidas e aplicadas metodologias inovadoras de processamento de dados de detecao remota, assim como novas implementacoes estuarinas e costeiras de modelos numericos. Atraves de imagens MODIS, otimizadas para o estudo de fenomenos costeiros, efetuou-se uma detecao rigorosa da pluma. Identificou-se uma relacao entre o sinal turbido nLw555 e o caudal, demonstrando-se este produto como um bom proxy para a observacao da pluma no oceano. As escalas temporais e espaciais da pluma foram caraterizadas atraves destas imagens, combinadas com dados de caudal fluvial, mare, vento e precipitacao, e tambem com indices climaticos relevantes. Para compreender a propagacao da pluma e caracterizar a sua dinâmica e impacto na circulacao costeira, foi desenvolvida uma aplicacao 3D de modelos estuarinos e costeiros com malhas aninhadas de resolucao variavel. Definiramse e analisaram-se diferentes cenarios de vento e descarga fluvial. A interacao da pluma do Rio Douro e do Minho foi ainda analisada atraves dos resultados de simulacoes baseadas num evento de inverno. Os compositos turbidos mostraram que a pluma e facilmente detetada quando o caudal e maior que 500 m3 s??1. A descarga fluvial e o vento sao os principais forcadores da sua propagacao, enquanto a mare e apenas importante na regiao proxima a embocadura do estuario. Observaram-se relacoes a uma escala interanual entre a turbidez da pluma e os indices climaticos East Atlantic e NAO, com uma correlacao maxima identificada com 1 e 3 meses de desfasamento, respetivamente. Com base nos resultados das simulacoes efetuadas, a pluma e classificada como de larga escala e de advecao superficial, apresentando caracteristicas de uma pluma prototipica. Em condicoes de caudal moderado a elevado, a descarga estuarina e suficiente para gerar uma corrente costeira para norte sem acao do vento. Em eventos de ventos leste, a propagacao da pluma e similar ao caso sem vento, com um aumento da velocidade da corrente. Uma corrente costeira para sul e unicamente identificada sob condicoes de forte vento de oeste. Ventos de norte tendem a estender a pluma para o largo, com uma inclinacao na direcao sudoeste, enquanto ventos de sul intensificam a corrente para norte, sendo a mistura das plumas do Douro e do Minho uma consequencia possivel. A analise desta interacao apontou a contribuicao do Douro como importante na estabilizacao da WIBP e nas trocas de agua entre o oceano e as Rias Baixas. A interacao da pluma do Douro com estuarios localizados a sul da sua foz e a confirmacao in situ da recirculacao observada nos resultados numericos afiguram-se como temas relevantes para investigacoes futuras. None

  7. 33 CFR 324.1 - General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Department of the Army (DA) permits to authorize the transportation of dredged material by vessel or other... transportation of dredged material for the purpose of dumping in the ocean waters also require DA permits under... the United States. Applicants for DA permits under this part should also refer to 33 CFR part 322 to...

  8. Estimated costs of advanced lung cancer care in a public reference hospital.

    PubMed

    Knust, Renata Erthal; Portela, Margareth Crisóstomo; Pereira, Claudia Cristina de Aguiar; Fortes, Guilherme Bastos

    2017-08-17

    To estimate the direct medical costs of advanced non-small cell lung cancer care. We assessed a cohort of 277 patients treated in the Brazilian National Cancer Institute in 2011. The costs were estimated from the perspective of the hospital as a service provider of reference for the Brazilian Unified Health System. The materials and procedures used were identified and quantified, per patient, and we assigned to them monetary values, consolidated in phases of the assistance defined. The analyses had a descriptive character with costs in Real (R$). Overall, the cohort represented a cost of R$2,473,559.91, being 71.5% related to outpatient care and 28.5% to hospitalizations. In the outpatient care, costs with radiotherapy (34%) and chemotherapy (22%) predominated. The results pointed to lower costs in the initial phase of treatment (7.2%) and very high costs in the maintenance phase (61.6%). Finally, we identified statistically significant differences of average cost by age groups, education levels, physical performance, and histological type. This study provides a current, useful, and relevant picture of the costs of patients with non-small cell lung cancer treated in a public hospital of reference and it provides information on the magnitude of the problem of cancer in the context of public health. The results confirm the importance of radiation treatment and hospitalizations as the main components of the cost of treatment. Despite some losses of follow-up, we assess that, for approximately 80% of the patients included in the study, the estimates presented herein are satisfactory for the care of the disease, from the perspective of a service provider of reference of the Brazilian Unified Health System, as it provides elements for the management of the service, as well as for studies that result in more rational forms of resource allocation. Estimar os custos médicos diretos da assistência ao câncer de pulmão não pequenas células avançado. Foi avaliada uma coorte de 277 pacientes matriculados no Instituto Nacional do Câncer em 2011. Os custos foram estimados sob a perspectiva do hospital como prestador de serviços de referência para o SUS. Insumos e procedimentos utilizados foram identificados e quantificados, por paciente, sendo a eles atribuídos valores monetários, consolidados por fases da assistência definidas. As análises tiveram caráter descritivo com custos em reais (R$). Em termos globais, a coorte representou um custo de R$2.473.559,91, sendo 71,5% relacionados à atenção ambulatorial e 28,5% as internações. Na atenção ambulatorial, predominaram os custos com radioterapia (34%) e quimioterapia (22%). Os resultados apontaram para custos menores na fase inicial de tratamento (7,2%) e custos muito elevados na fase de manutenção (61,6%). Por fim, identificaram-se diferenças estatisticamente significativas das médias dos custos por faixas etárias, níveis de escolaridade, desempenho físico e tipo histológico. Este estudo fornece um retrato atual, útil e relevante sobre os custos de pacientes com câncer de pulmão não pequenas células assistidos em um hospital público de referência e provê elementos sobre a magnitude do problema do câncer no âmbito da saúde pública. Os resultados ratificam a importância do tratamento radioterápico e das internações como principais componentes de custo do tratamento. Apesar de algumas perdas de seguimento avalia-se que, para cerca de 80% dos pacientes incluídos no estudo, as estimativas aqui apresentadas sejam satisfatoriamente fidedignas ao cuidado da doença, sob a perspectiva de um prestador de referência do SUS, fornecendo elementos para a gestão do serviço, bem como para estudos que redundem em formas mais racionais de alocação de recursos.

  9. Characterization of sulfur oxidizing bacteria related to biogenic sulfuric acid corrosion in sludge digesters.

    PubMed

    Huber, Bettina; Herzog, Bastian; Drewes, Jörg E; Koch, Konrad; Müller, Elisabeth

    2016-07-18

    Biogenic sulfuric acid (BSA) corrosion damages sewerage and wastewater treatment facilities but is not well investigated in sludge digesters. Sulfur/sulfide oxidizing bacteria (SOB) oxidize sulfur compounds to sulfuric acid, inducing BSA corrosion. To obtain more information on BSA corrosion in sludge digesters, microbial communities from six different, BSA-damaged, digesters were analyzed using culture dependent methods and subsequent polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE). BSA production was determined in laboratory scale systems with mixed and pure cultures, and in-situ with concrete specimens from the digester headspace and sludge zones. The SOB Acidithiobacillus thiooxidans, Thiomonas intermedia, and Thiomonas perometabolis were cultivated and compared to PCR-DGGE results, revealing the presence of additional acidophilic and neutrophilic SOB. Sulfate concentrations of 10-87 mmol/L after 6-21 days of incubation (final pH 1.0-2.0) in mixed cultures, and up to 433 mmol/L after 42 days (final pH <1.0) in pure A. thiooxidans cultures showed huge sulfuric acid production potentials. Additionally, elevated sulfate concentrations in the corroded concrete of the digester headspace in contrast to the concrete of the sludge zone indicated biological sulfur/sulfide oxidation. The presence of SOB and confirmation of their sulfuric acid production under laboratory conditions reveal that these organisms might contribute to BSA corrosion within sludge digesters. Elevated sulfate concentrations on the corroded concrete wall in the digester headspace (compared to the sludge zone) further indicate biological sulfur/sulfide oxidation in-situ. For the first time, SOB presence and activity is directly relatable to BSA corrosion in sludge digesters.

  10. Staging Dementia Using Clinical Dementia Rating Scale Sum of Boxes Scores

    PubMed Central

    O'Bryant, Sid E.; Waring, Stephen C.; Cullum, C. Munro; Hall, James; Lacritz, Laura; Massman, Paul J.; Lupo, Philip J.; Reisch, Joan S.; Doody, Rachelle

    2012-01-01

    Background The Clinical Dementia Rating Scale Sum of Boxes (CDR-SOB) score is commonly used, although the utility regarding this score in staging dementia severity is not well established. Obiective To investigate the effectiveness of CDRSOB scores in staging dementia severity compared with the global CDR score. Design Retrospective study. Setting Texas Alzheimer's Research Consortium minimum data set cohort. Participants A total of 1577 participants (110 controls, 202 patients with mild cognitive impairment, and 1265 patients with probable Alzheimer disease) were available for analysis. Main Outcome Measures Receiver operating characteristic curves were generated from a derivation sample to determine optimal cutoff scores and ranges, which were then applied to the validation sample. Results Optimal ranges of CDR-SOB scores corresponding to the global CDR scores were 0.5 to 4.0 for a global score of 0.5, 4.5 to 9.0 for a global score of 1.O, 9.5 to 15.5 for a global score of 2.0, and 16.0 to 18.0 for a global score of 3.0. When applied to the validation sample, κ scores ranged from 0.86 to 0.94 (P <.001 for all), with 93.0% of the participants falling within the new staging categories. Conclusions The CDR-SOB score compares well with the global CDR score for dementia staging. Owing to the increased range of values, the CDR-SOB score offers several advantages over the global score, including increased utility in tracking changes within and between stages of dementia severity. Interpretive guidelines for CDR-SOB scores are provided. PMID:18695059

  11. Hypothalamic-Pituitary-Thyroid Axis Perturbations in Male Mice by CNS-Penetrating Thyromimetics.

    PubMed

    Ferrara, Skylar J; Bourdette, Dennis; Scanlan, Thomas S

    2018-07-01

    Thyromimetics represent a class of experimental drugs that can stimulate tissue-selective thyroid hormone action. As such, thyromimetics should have effects on the hypothalamic-pituitary-thyroid (HPT) axis, but details of this action and the subsequent effects on systemic thyroid hormone levels have not been reported to date. Here, we compare the HPT-axis effects of sobetirome, a well-studied thyromimetic, with Sob-AM2, a newly developed prodrug of sobetirome that targets sobetirome distribution to the central nervous system (CNS). Similar to endogenous thyroid hormone, administration of sobetirome and Sob-AM2 suppress HPT-axis gene transcript levels in a manner that correlates to their specific tissue distribution properties (periphery vs CNS, respectively). Dosing male C57BL/6 mice with sobetirome and Sob-AM2 at concentrations ≥10 μg/kg/d for 29 days induces a state similar to central hypothyroidism characterized by depleted circulating T4 and T3 and normal TSH levels. However, despite the systemic T4 and T3 depletion, the sobetirome- and Sob-AM2-treated mice do not show signs of hypothyroidism, which may result from the presence of the thyromimetic in the thyroid hormone-depleted background.

  12. Characterization of a major 31-kilodalton peptidoglycan-bound protein of Legionella pneumophila

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Butler, C.A.; Hoffman, P.S.

    1990-05-01

    A 31-kilodalton (kDa) protein was solubilized from the peptidoglycan (PG) fraction of Legionella pneumophila after treatment with either N-acetylmuramidase from the fungus Chalaropsis sp. or with mutanolysin from Streptomyces globisporus. The protein exhibited a ladderlike banding pattern by autoradiography when radiolabeled ((35S)cysteine or (35S)methionine) PG material was extensively treated with hen lysozyme. The banding patterns ranging between 31 and 45 kDa and between 55 and 60 kDa resolved as a single 31-kDa protein when the material was subsequently treated with N-acetylmuramidase. Analysis of the purified 31-kDa protein for diaminopimelic acid by gas chromatography revealed 1 mol of diaminopimelic acid permore » mol of protein. When outer membrane PG material containing the major outer membrane porin protein was treated with N-acetylmuramidase or mutanolysin, both the 28.5-kDa major outer membrane protein and the 31-kDa protein were solubilized from the PG material under reducing conditions. In the absence of 2-mercaptoethanol, a high-molecular-mass complex (100 kDa) was resolved. The results of this study indicate that a 31-kDa PG-bound protein is a major component of the cell wall of L. pneumophila whose function may be to anchor the major outer membrane protein to PG. Finally, a survey of other Legionella species and other serogroups of L. pneumophila suggested that PG-bound proteins may be a common feature of this genus.« less

  13. CORRELATION BETWEEN PRE AND POSTOPERATIVE LEVELS OF GLP-1/GLP-2 AND WEIGHT LOSS AFTER ROUX-EN-Y GASTRIC BYPASS: A PROSPECTIVE STUDY.

    PubMed

    Cazzo, Everton; Gestic, Martinho Antonio; Utrini, Murillo Pimentel; Pareja, José Carlos; Chaim, Elinton Adami; Geloneze, Bruno; Barreto, Maria Rita Lazzarini; Magro, Daniéla Oliveira

    2016-01-01

    The role of gut hormones in glucose homeostasis and weight loss achievement and maintenance after bariatric surgery appears to be a key point in the understanding of the beneficial effects observed following these procedures. To determine whether there is a correlation between the pre and postoperative levels of both GLP-1 and GLP-2 and the excess weight loss after Roux-en-Y gastric bypass (RYGB). An exploratory prospective study which enrolled 11 individuals who underwent RYGB and were followed-up for 12 months. GLP-1 and GLP-2 after standard meal tolerance test (MTT) were determined before and after surgery and then correlated with the percentage of excess loss (%EWL). GLP-2 AUC presented a significant postoperative increase (945.3±449.1 vs.1787.9±602.7; p=0.0037); GLP-1 AUC presented a non-significant trend towards increase after RYGB (709.6±320.4 vs. 1026.5±714.3; p=0.3808). Mean %EWL was 66.7±12.2%. There was not any significant correlation between both the pre and postoperative GLP-1 AUCs and GLP-2 AUCs and the %EWL achieved after one year. There was no significant correlation between the pre and postoperative levels of the areas under the GLP-1 and GLP-2 curves with the percentage of weight loss reached after one year. O papel de hormônios gastrointestinais sobre a homeostase glicêmica e a obtenção e manutenção da perda de peso após a cirurgia bariátrica parece ser elemento fundamental na compreensão dos benefícios observados após estes procedimentos. Determinar se há correlação entre os níveis pré e pós-operatórios de GLP-1 e GLP-2 com a perda do excesso de peso após o bypass gástrico em Y-de-Roux. Estudo prospectivo exploratório que envolveu 11 indivíduos submetidos ao bypass gástrico, acompanhados por 12 meses. Os níveis GLP-1 e GLP-2 após um teste de refeição padrão foram determinados antes e 12 meses após a operação e então foram correlacionados com o percentual de perda do excesso de peso. Houve aumento significativo da área sob a curva do GLP-2 após a operação (945,3±449,1 vs. 1787,9±602,7; p=0,0037); a área sob a curva do GLP-1 apresentou tendência não-significativa à elevação após o procedimento (709,6±320,4 vs. 1026,5±714,3; p=0,3808). O percentual médio de perda de peso foi 66,7±12,2%. Não houve nenhuma correlação significativa entre os níveis pré e pós-operatórios das áreas sob as curvas de GLP-1 e GLP-2 com o percentual de perda de peso atingido após um ano.

  14. Coerência espectroscópica de famílias de asteróides

    NASA Astrophysics Data System (ADS)

    Mothé Diniz, T.; Roig, F. V.

    2003-08-01

    As Famílias de asteróides são caracterizadas como agrupamentos de objetos provenientes da quebra por colisão de corpos precursores. Desta forma, seus membros devem preservar relações genéticas que podem ser traduzidas sob a análise de suas características espectrais. Neste trabalho é apresentado o primeiro estudo espectroscópico de todas as famílias de asteróides do cinturão principal. Para tal, a divisão em famílias foi refeita utilizando-se o método HCM com uma base de elementos próprios analíticos (Knezevic e Milani, Jun 2001) e para o estudo espectroscópico foram utilizadas diversas campanhas de observação espectroscópica, tais o S3OS2 e o SMASSII, bem como outros dados disponíveis na literatura. A homogeneidade espectroscópica de cada família foi avaliada através da verificação das classes espectroscópicas presentes, bem como da comparação destes espectros com os de objetos de fundo, localizados na vizinhança da família. Vinte e duas famílias foram analisadas (as que possuíam mais do que 3 membros com espectro) e, dentre as principais conclusões pode-se citar a homogeneidade espectroscópica e, provavelmente mineralógica das famílias de Vesta, Eunomia, Hoffmeister, Dora, Merxia, Agnia, Koronis e Veritas. Esta última em particular, foi tida como uma família não homogênea espectroscopicamente em trabalho anterior (Di Martino et al. 1997). Outro resultado interessante é, por um lado, a aparente falta de homogeneidade dos membros da família de Eos, e por outro sua forte distinção dos objetos de fundo. O oposto ocorre na família de Themis, esta apresentando-se espectroscopicamente compatível com os objetos de fundo, mas com grande homogeneidade taxonômica entre seus membros. Algumas das famílias apresentam asteróides "intrusos" (objetos cujas características físicas não são compatíveis com aquelas dos membros da família) que, de modo geral desaparecem ao se considerarem níveis mais baixos de corte para a divisão da família no HCM, sem prejuízo para o agrupamento dos demais membros.

  15. "Click chemistry" in tailor-made polymethacrylates bearing reactive furfuryl functionality: a new class of self-healing polymeric material.

    PubMed

    Kavitha, A Amalin; Singha, Nikhil K

    2009-07-01

    This investigation reports the effective use of the Diels-Alder (DA) reaction, a "click reaction" in the preparation of thermally amendable and self-healing polymeric materials having reactive furfuryl functionality. In this case, the DA and retro-DA (rDA) reactions were carried out between the tailor-made homo- and copolymer of furfuryl methacrylate prepared by atom-transfer radical polymerization and a bismaleimide (BM). The kinetic studies of DA and rDA reactions were carried out using Fourier transform infrared spectroscopy. The DA polymers were insoluble in toluene at room temperature. When the DA polymers were heated at 100 degrees C in toluene, it was soluble. This is because of the cleavage between furfuryl functionality and BM. The chemical cross-link density was determined by the Flory-Rehner equation. The cross-linked polymer showed much greater adhesive strength at room temperature, but the adhesive strength was quite low at higher temperature. The self-healing capability was studied by using scanning electron microscopy analysis. The thermal and dynamic mechanical properties of the thermally amendable cross-linked materials were investigated by thermogravimetric analysis and dynamic mechanical analysis.

  16. Analysis of Family Clinical, vision of service nurses.

    PubMed

    Raimundi, Daniele Merisio; Ferreira, Francieli Furtado; Lima, Fernanda Cristina Aguiar; Siqueira, Valeria de Carvalho Araújo

    2016-06-01

    to know the practice of the Family Clinic in Cuiaba and its relationship with the precepts of the expanded clinic, from the perspective of the service nurses. qualitative descriptive research, data collection with semi-structured interviews and results analyzed according to the method of thematic content analysis. for nurses working in the service, this assumes a differentiated and innovative proposal, which seeks to correlate with shared management in its three spheres. Although most do not know the Enlarged Clinic term in his speech cited its main principles and its tools. The greatest potential described were related to the Support Center for Health and popular participation, and as challenges, the lack of community health worker, the national health establishment registration and the difficulty of operation due to the profile of the professionals technical level arising from secondary care. The clinic has positive aspects that can contribute to the advancement of the profession, to train health professionals and an innovative primary care model. Therefore, it emphasizes the need for implementation of continuing education in order to realize its proposal, and further studies on site. conhecer a prática da Clínica da Família em Cuiabá e sua relação com os preceitos da clínica ampliada, sob a perspectiva dos enfermeiros do serviço. pesquisa descritiva qualitativa, coleta de dados com entrevista semi-estruturada e resultados analisados segundo o método de análise de conteúdo do tipo temática. para os enfermeiros atuantes no serviço, este assume uma proposta diferenciada e inovadora, no qual busca se correlacionar com a gestão compartilhada em suas três esferas. Apesar de a maioria não conhecer o termo Clínica Ampliada em suas falas citaram seus principais preceitos e suas ferramentas. As maiores potencialidades descritas foram a relação com o Núcleo de Apoio à Saúde da Família e a participação popular, e como desafios, a falta de agente comunitário de saúde, do cadastro nacional de estabelecimento de saúde e a dificuldade de atuação devido ao perfil dos profissionais de nível técnico advindos da atenção secundária. a clínica possui aspectos positivos que podem contribuir para o progresso da profissão, para a formação de profissionais da saúde e para um modelo de assistência de nível primário inovador. Logo, enfatiza-se a necessidade de implantação da educação permanente com o objetivo de concretizar sua proposta, além de estudos posteriores no local.

  17. The deep-sea glass sponge Lophophysema eversa harbours potential symbionts responsible for the nutrient conversions of carbon, nitrogen and sulfur.

    PubMed

    Tian, Ren-Mao; Sun, Jin; Cai, Lin; Zhang, Wei-Peng; Zhou, Guo-Wei; Qiu, Jian-Wen; Qian, Pei-Yuan

    2016-09-01

    Glass sponge (Hexactinellida, Porifera) is a special lineage because of its unique tissue organization and skeleton material. Structure and physiology of glass sponge have been extensively studied. However, our knowledge of the glass sponge-associated microbial community and of the interaction with the host is rather limited. Here, we performed genomic studies on the microbial community in the glass sponge Lophophysema eversa in seamount. The microbial community was dominated by an ammonia-oxidizing archaeum (AOA), a nitrite-oxidizing bacterium (NOB) and a sulfur-oxidizing bacterium (SOB), all of which were autotrophs. Genomic analysis on the AOA, NOB and SOB in the sponge revealed specific functional features of sponge-associated microorganisms in comparison with the closely related free-living relatives, including chemotaxis, phage defence, vitamin biosynthesis and nutrient uptake among others, which are related to ecological functions. The three autotrophs play essential roles in the cycles of carbon, nitrogen and sulfur in the microenvironment inside the sponge body, and they are considered to play symbiotic roles in the host as scavengers of toxic ammonia, nitrite and sulfide. Our study extends knowledge regarding the metabolism and the evolution of chemolithotrophs inside the invertebrate body. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  18. Determination of perfluorinated compounds (PFCs) in various foodstuff packaging materials used in the Greek market.

    PubMed

    Zafeiraki, Effrosyni; Costopoulou, Danae; Vassiliadou, Irene; Bakeas, Evangelos; Leondiadis, Leondios

    2014-01-01

    Perfluorinated compounds (PFCs) are used in food packaging materials as coatings/additives for oil and moisture resistance. In the current study, foodstuff-packaging materials collected from the Greek market, made of paper, paperboard or aluminum foil were analyzed for the determination of PFCs. For the analysis of the samples, pressurized liquid extraction (PLE), liquid chromatography–tandem mass spectrometry (LC–MS/MS) and isotope dilution method were applied to develop a specific and sensitive method of analysis for the quantification of 12 PFCs: perfluorobutanoic acid (PFBA), perfluoropentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoA), perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS) and perfluorooctane sulfonate (PFOS) and the qualitative detection of 5 more: perfluorotridecanoic acid (PFTrDA), perfluorotetradecanoic acid (PFTeDA), perflyohexadecanoic acid (PFHxDA), perfluorooctadecanoic acid (PFODA) and perfluorodecane sulfonate (PFDS). No PFCs were quantified in aluminum foil wrappers, baking paper materials or beverage cups. PFTrDA, PFTeDA and PFHxDA were detected in fast food boxes. In the ice cream cup sample only PFHxA was found. On the other hand, several PFCs were quantified and detected in fast food wrappers, while the highest levels of PFCs were found in the microwave popcorn bag. PFOA and PFOS were not detected in any of the samples. Compared to other studies from different countries, very low concentrations of PFCs were detected in the packaging materials analyzed. Our results suggest that probably no serious danger for consumers’ health can be associated with PFCs contamination of packaging materials used in Greece.

  19. Resultados do desenvolvimento de um propulsor à plasma no Brasil

    NASA Astrophysics Data System (ADS)

    Ferreira, I. S.; Ferreira, J. L.

    2003-08-01

    Uma das partes mais importantes de um satélite é o controle de atitude do mesmo. E se tratando de um satélite científico, a atenção para este sistema deve ser redobrada. Uma possibilidade atraente para executar esta tarefa é a propulsão elétrica. Aqui, mostraremos resultados obtidos pelo propulsor à plasma PHALL-01, desenvolvido na Universidade de Brasília entre 2000 e 2003. Este é derivado do propulsor russo SPT-100 (Stationary Plasma Thruster), mas com o emprego inovador de um arranjo de imãs permanentes como fonte do campo magnético, este último o agente da aceleração do plasma. Esta alteração foi motivada pelo objetivo de que o mesmo operasse com o mínimo de potência elétrica. A partir da formulação teórica do mecanismo de aceleração, tendo como base as equações da magnetohidrodinâmica, pode-se obter vínculos sob os quais o propulsor pudesse ser construído. O mais forte destes é o que dita a topologia do campo magnético. Sendo assim, foram realizadas simulações computacionais, que definiram a geometria do propulsor. Após construído, este foi diagnosticado usando-se sondas de Langmuir e analisadores de energia. Como resultados, obtivemos a distribuição espacial da temperatura, densidade e potencial do plasma, bem como a distribuição angular do feixe produzido pelo mesmo em vários regimes de operação. O espectro de energia do feixe de plasma também foi medido, indicando íons de até 560eV. Combinando estes resultados, calculou-se o empuxo do propulsor: 84mN; e o impulso específico: 1083s. Estes demonstram que o mesmo estará qualificado, num futuro próximo, para o emprego no controle de atitude de satélites científicos, ou até mesmo como parte do conjunto propulsor primário, responsáveis pela transferência de órbitas.

  20. Interaction Effects of Season of Birth and Cytokine Genes on Schizotypal Traits in the General Population

    PubMed Central

    Korovaitseva, Galina I.; Lezheiko, Tatyana V.; Golimbet, Vera E.

    2017-01-01

    Literature suggests that the effect of winter birth on vulnerability to schizophrenia might be mediated by increased expression of proinflammatory cytokines due to prenatal infection and its inadequate regulation by anti-inflammatory factors. As the response of the immune system depends on genotype, this study assessed the interaction effects of cytokine genes and season of birth (SOB) on schizotypy measured with the Schizotypal Personality Questionnaire (SPQ-74). We searched for associations of IL1B rs16944, IL4 rs2243250, and IL-1RN VNTR polymorphisms, SOB, and their interactions with the SPQ-74 total score in a sample of 278 healthy individuals. A significant effect of the IL4 X SOB interaction was found, p = 0.007 and η2 = 0.028. We confirmed this effect using an extended sample of 373 individuals. Homozygotes CC born in winter showed the highest SPQ total score and differed significantly from winter-born T allele carriers, p = 0.049. This difference was demonstrated for cognitive-perceptual and disorganized but not interpersonal dimensions. The findings are consistent with the hypothesis that the cytokine genes by SOB interaction can influence variability of schizotypal traits in the general population. The IL4 T allele appeared to have a protective effect against the development of positive and disorganized schizotypal traits in winter-born individuals. PMID:29464121

  1. Interaction Effects of Season of Birth and Cytokine Genes on Schizotypal Traits in the General Population.

    PubMed

    Alfimova, Margarita V; Korovaitseva, Galina I; Lezheiko, Tatyana V; Golimbet, Vera E

    2017-01-01

    Literature suggests that the effect of winter birth on vulnerability to schizophrenia might be mediated by increased expression of proinflammatory cytokines due to prenatal infection and its inadequate regulation by anti-inflammatory factors. As the response of the immune system depends on genotype, this study assessed the interaction effects of cytokine genes and season of birth (SOB) on schizotypy measured with the Schizotypal Personality Questionnaire (SPQ-74). We searched for associations of IL1B rs16944, IL4 rs2243250, and IL-1RN VNTR polymorphisms, SOB, and their interactions with the SPQ-74 total score in a sample of 278 healthy individuals. A significant effect of the IL4 X SOB interaction was found, p = 0.007 and η 2 = 0.028. We confirmed this effect using an extended sample of 373 individuals. Homozygotes CC born in winter showed the highest SPQ total score and differed significantly from winter-born T allele carriers, p = 0.049. This difference was demonstrated for cognitive-perceptual and disorganized but not interpersonal dimensions. The findings are consistent with the hypothesis that the cytokine genes by SOB interaction can influence variability of schizotypal traits in the general population. The IL4 T allele appeared to have a protective effect against the development of positive and disorganized schizotypal traits in winter-born individuals.

  2. Evaluation of laser therapy and alpha-lipoic acid for the treatment of burning mouth syndrome: a randomized clinical trial.

    PubMed

    Barbosa, Natália Guimarães; Gonzaga, Amanda Katarinny Goes; de Sena Fernandes, Luzia Leiros; da Fonseca, Aldilane Gonçalves; Queiroz, Salomão Israel Monteiro Lourenço; Lemos, Telma Maria Araújo Moura; da Silveira, Éricka Janine Dantas; de Medeiros, Ana Miryam Costa

    2018-03-03

    The aim of this study was to evaluate the efficacy of low-level laser therapy (LLLT) and alpha-lipoic acid (ALA) in the treatment of burning mouth syndrome (BMS) and secondary oral burning (SOB) by unstimulated sialometry, symptom assessment, and measurement of salivary TNF-α levels. Forty-four patients were randomized into four treatment groups: BMS/laser (n = 10), BMS/ALA (n = 5), SOB/laser (n = 15), and SOB/ALA (n = 14). The control group consisted of eight healthy female subjects. Unstimulated salivary flow was measured before and after treatment, and the collected saliva was stored at - 20 °C for the analysis of TNF-α. Symptoms were evaluated before and after treatment using a pain visual analog scale. Most patients were women (81.8%) during menopause (72.2%). LLLT and ALA were efficient in increasing salivary flow only in BMS but provided symptom relief in both conditions. TNF-α levels did not differ between patients with BMS and SOB or between those patients and the control group. No differences were observed in posttreatment TNF-α levels in either condition. The results of this study suggest that LLLT and ALA are efficient therapies in reducing burning mouth symptoms, with LLLT being more efficient than ALA.

  3. The Effects of Season of Birth on the Inflammatory Response to Psychological Stress in Hainan Island, China.

    PubMed

    Yazawa, Aki; Inoue, Yosuke; Stickley, Andrew; Li, Dandan; Du, Jianwei; Watanabe, Chiho

    2015-01-01

    Season of birth (SOB) has been investigated as one of the environmental factors that might epigenetically determine the physiology of individuals. This study investigated the role of SOB in the association between Quality of Life (QOL), a proxy of psychological stress status, and C-reactive protein (CRP) concentration (i.e., inflammatory status) among 1,085 adults (aged 20-57 years old) in Hainan Island, China. High sensitivity CRP concentration was measured in dried blood spot samples, while the abbreviated version of the World Health Organization's QOL questionnaire was used to gather information on six QOL domains. Analysis stratified by three historically distinct age groups revealed a significant association between CRP concentration, SOB, QOL and an interaction between SOB and QOL among the youngest and oldest groups. In the oldest group, those born in the dry season had a higher CRP concentration with worse QOL whereas in the youngest group, there was a higher CRP concentration with better QOL. Annual per capita rice production, a proxy of population nutritional status in the year of birth, was found to predict CRP concentration only among the second oldest group. These findings suggest that the early environment might affect the immune response to psychological stress in adulthood and that its effect may differ by the time period in which people were born.

  4. Thal Amyloid Stages Do Not Significantly Impact the Correlation Between Neuropathological Change and Cognition in the Alzheimer Disease Continuum.

    PubMed

    Serrano-Pozo, Alberto; Qian, Jing; Muzikansky, Alona; Monsell, Sarah E; Montine, Thomas J; Frosch, Matthew P; Betensky, Rebecca A; Hyman, Bradley T

    2016-06-01

    The 2012 neuropathological criteria for the diagnosis of Alzheimer disease (AD) summarize the extent of AD neuropathological change with an ABC score, which is a composite of the Thal stage of amyloid deposition (A), the Braak stage of neurofibrillary tangles (NFTs) (B), and the CERAD neuritic plaque score (C). NFTs and neuritic plaques are well-established contributors to cognitive impairment, but whether the Thal amyloid stage independently predicts antemortem cognition remains unknown. We used the National Alzheimer's Coordinating Center autopsy data set to build adjacent-categories logit regression models with CDR-SOB and Mini-Mental State Examination (MMSE) scores as cognitive outcome variables. Increasing CERAD scores were independently associated with higher CDR-SOB scores, whereas increasing Braak NFT stages predicted both higher CDR-SOB and lower MMSE scores. Increasing Thal amyloid stages were not significantly independently associated with either outcome measure. Increasing ABC scores predicted higher CDR-SOB and lower MMSE scores. These results raise the possibility that Thal amyloid stages do not substantially contribute to predicting antemortem cognition compared to CERAD neuritic plaque scores and Braak NFT stages, and suggest that the diffuse amyloid deposits participating in the assignment of Thal amyloid stages are neutral with respect to clinically detectable cognitive and functional changes. © 2016 American Association of Neuropathologists, Inc. All rights reserved.

  5. Theoretical and methodological approaches in discourse analysis.

    PubMed

    Stevenson, Chris

    2004-01-01

    Discourse analysis (DA) embodies two main approaches: Foucauldian DA and radical social constructionist DA. Both are underpinned by social constructionism to a lesser or greater extent. Social constructionism has contested areas in relation to power, embodiment, and materialism, although Foucauldian DA does focus on the issue of power Embodiment and materialism may be especially relevant for researchers of nursing where the physical body is prominent. However, the contested nature of social constructionism allows a fusion of theoretical and methodological approaches tailored to a specific research interest. In this paper, Chris Stevenson suggests a framework for working out and declaring the DA approach to be taken in relation to a research area, as well as to aid anticipating methodological critique. Method, validity, reliability and scholarship are discussed from within a discourse analytic frame of reference.

  6. Theoretical and methodological approaches in discourse analysis.

    PubMed

    Stevenson, Chris

    2004-10-01

    Discourse analysis (DA) embodies two main approaches: Foucauldian DA and radical social constructionist DA. Both are underpinned by social constructionism to a lesser or greater extent. Social constructionism has contested areas in relation to power, embodiment, and materialism, although Foucauldian DA does focus on the issue of power. Embodiment and materialism may be especially relevant for researchers of nursing where the physical body is prominent. However, the contested nature of social constructionism allows a fusion of theoretical and methodological approaches tailored to a specific research interest. In this paper, Chris Stevenson suggests a frame- work for working out and declaring the DA approach to be taken in relation to a research area, as well as to aid anticipating methodological critique. Method, validity, reliability and scholarship are discussed from within a discourse analytic frame of reference.

  7. Influence of maxillary posterior discrepancy on upper molar vertical position and facial vertical dimensions in subjects with or without skeletal open bite.

    PubMed

    Arriola-Guillén, Luis Ernesto; Aliaga-Del Castillo, Aron; Pérez-Vargas, Luis Fernando; Flores-Mir, Carlos

    2016-06-01

    To determine the influence of maxillary posterior discrepancy on upper molar vertical position and dentofacial vertical dimensions in individuals with or without skeletal open bite (SOB). Pre-treatment lateral cephalograms of 139 young adults were examined. The sample was divided into eight groups categorized according to their sagittal and vertical skeletal facial growth pattern and maxillary posterior discrepancy (present or absent). Upper molar vertical position, overbite, lower anterior facial height and facial height ratio were measured. Independent t-test was performed to determine differences between the groups considering maxillary posterior discrepancy. Principal component analysis and MANCOVA test were also used. No statistically significant differences were found comparing the molar vertical position according to maxillary posterior discrepancy for the SOB Class I group or the group with adequate overbite. Significant differences were found in SOB Class II and Class III groups. In addition, an increased molar vertical position was found in the group without posterior discrepancy. Some variables closely related with the individual's intrinsic craniofacial development that could influence the evaluated vertical measurements were not considered. Overall maxillary posterior discrepancy does not appear to have a clear impact on upper molar vertical position or facial vertical dimensions. Only the SOB Class III group without posterior discrepancy had a significant increased upper molar vertical position. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  8. A study on a dental device for the prevention of mucosal dose enhancement caused by backscatter radiation from dental alloy during external beam radiotherapy.

    PubMed

    Katsura, Kouji; Utsunomiya, Satoru; Abe, Eisuke; Sakai, Hironori; Kushima, Naotaka; Tanabe, Satoshi; Yamada, Takumi; Hayakawa, Takahide; Yamanoi, Yoshihiko; Kimura, Syuhei; Wada, Shinichi; Aoyama, Hidefumi; Hayashi, Takafumi

    2016-11-01

    The changes in dose distribution caused by backscatter radiation from a common commercial dental alloy (Au-Ag-Pd dental alloy; DA) were investigated to identify the optimal material and thicknesses of a dental device (DD) for effective prevention of mucositis. To this end, 1 cm 3 of DA was irradiated with a 6-MV X-ray beam (100 MU) in a field size of 10 × 10 cm 2 using a Novalis TX linear accelerator. Ethylene vinyl acetate copolymer, polyolefin elastomer, and polyethylene terephthalate (PET) were selected as DD materials. The depth dose along the central axis was determined with respect to the presence/absence of DA and DDs at thicknesses of 1-10 mm using a parallel-plate ionization chamber. The dose in the absence of DDs showed the lowest value at a distance of 5 mm from the DA surface and gradually increased with distance between the measurement point and the DA surface for distances of ≥5 mm. Except for PET, no significant difference between the DA dose curves for the presence and absence of DDs was observed. In the dose curve, PET showed a slightly higher dose for DA with DD than for DA without DD for thicknesses of ≥4 mm. The findings herein suggest that the optimal DD material for preventing local dose enhancement of the mucosa caused by DA backscatter radiation should have a relatively low atomic number and physical density and that optimal DD thickness should be chosen considering backscatter radiation and percentage depth dose. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  9. Effects of Chemistry and Processing on the Fracture Related Properties of P/M Alloy CT91.

    DTIC Science & Technology

    1985-08-01

    Paris- Erdogan equation [151]. da/dN = AAk’ (8) where A and m are material constants. Stage II is generally characterized by a continuum mechanism...1. Paris and Erdogan [151] da/dN = CAKm (15) where da/dN = crack growth per cycle C, m = material constants AK = stress intensity parameter range The...extensometer was placed on two strips of masking tape to avoid notching the specimen and was carefully attached by two springs. A plastic bag was placed

  10. In-Vessel Composting of Simulated Long-Term Missions Space-Related Solid Wastes

    NASA Technical Reports Server (NTRS)

    Rodriguez-Carias, Abner A.; Sager, John; Krumins, Valdis; Strayer, Richard; Hummerick, Mary; Roberts, Michael S.

    2002-01-01

    Reduction and stabilization of solid wastes generated during space missions is a major concern for the Advanced Life Support - Resource Recovery program at the NASA, Kennedy Space Center. Solid wastes provide substrates for pathogen proliferation, produce strong odor, and increase storage requirements during space missions. A five periods experiment was conducted to evaluate the Space Operation Bioconverter (SOB), an in vessel composting system, as a biological processing technology to reduce and stabilize simulated long-term missions space related solid-wastes (SRSW). For all periods, SRSW were sorted into components with fast (FBD) and slow (SBD) biodegradability. Uneaten food and plastic were used as a major FBD and SBD components, respectively. Compost temperature (C), CO2 production (%), mass reduction (%), and final pH were utilized as criteria to determine compost quality. In period 1, SOB was loaded with a 55% FBD: 45% SBD mixture and was allowed to compost for 7 days. An eleven day second composting period was conducted loading the SOB with 45% pre-composted SRSW and 55% FBD. Period 3 and 4 evaluated the use of styrofoam as a bulking agent and the substitution of regular by degradable plastic on the composting characteristics of SRSW, respectively. The use of ceramic as a bulking agent and the relationship between initial FBD mass and heat production was investigated in period 5. Composting SRSW resulted in an acidic fermentation with a minor increase in compost temperature, low CO2 production, and slightly mass reduction. Addition of styrofoam as a bulking agent and substitution of regular by biodegradable plastic improved the composting characteristics of SRSW, as evidenced by higher pH, CO2 production, compost temperature and mass reduction. Ceramic as a bulking agent and increase the initial FBD mass (4.4 kg) did not improve the composting process. In summary, the SOB is a potential biological technology for reduction and stabilization of mission space-related solid wastes. However, the success of the composting process may depend of the physical characteristics (particle size, porosity, structure, texture) of the SBD components which would require pre-processing of solid wastes before placing them in the SOB.

  11. Development, health, and international policy: the research and innovation dimension.

    PubMed

    Buss, Paulo Marchiori; Chamas, Claudia; Faid, Miriam; Morel, Carlos

    2016-11-03

    This text main objective is to discuss development and health from the perspective of the influence of global health governance, using as the tracer the dimension of research, development, and innovation policies in health, which relate to both important inputs for the health system, like drugs and medicines, vaccines, diagnostic reagents, and equipment, and innovative concepts and practices for the improvement of health systems and public health. The authors examine the two main macro-processes that influence development and health: the post-2015 Development Agenda and the process under way in the World Health Organization concerning research and development, intellectual property, and access to health inputs. The article concludes, first, that much remains to be done for the Agenda to truly represent a coherent and viable international political pact, and that the two macro-processes related to innovation in health need to be streamlined. But this requires democratization of participation by the main stakeholders - patients and the general population of the poorest countries - since this is the only way to overcome a "zero sum" result in the clash in the current debates among member State representatives. Resumo: O objetivo central deste texto é discutir desenvolvimento e saúde sob a ótica da influência da governança da saúde global, utilizando como traçador a dimensão das políticas de pesquisa, desenvolvimento e inovação em saúde, que se referem, de um lado, a insumos importantes para o sistema de saúde - como fármacos e medicamentos, vacinas, reativos para diagnóstico e equipamentos e, de outro, a conceitos e práticas inovadoras para o aperfeiçoamento dos sistemas de saúde e da saúde pública. Examina os dois principais macroprocessos que influenciam o desenvolvimento e a saúde: a Agenda do Desenvolvimento para o pós-2015 e o processo sobre pesquisa e desenvolvimento, propriedade intelectual e acesso a insumos em saúde em curso na Organização Mundial da Saúde. Conclui que muito há que ser feito para que a referida Agenda possa representar um pacto político internacional coerente e viável, e que os dois macroprocessos relacionados com a inovação em saúde precisam ser agilizados, mas para isto torna-se necessária a democratização da participação dos maiores interessados - os pacientes e, de modo geral, a população dos países mais pobres - pois só desta maneira será superada a "soma zero" em que se encontra o embate entre os representantes de Estados-membros nos debates atuais.

  12. Biaxial seismic behaviour of reinforced concrete columns =

    NASA Astrophysics Data System (ADS)

    Rodrigues, Hugo Filipe Pinheiro

    A analise dos efeitos dos sismos mostra que a investigacao em engenharia sismica deve dar especial atencao a avaliacao da vulnerabilidade das construcoes existentes, frequentemente desprovidas de adequada resistencia sismica tal como acontece em edificios de betao armado (BA) de muitas cidades em paises do sul da Europa, entre os quais Portugal. Sendo os pilares elementos estruturais fundamentais na resistencia sismica dos edificios, deve ser dada especial atencao a sua resposta sob acoes ciclicas. Acresce que o sismo e um tipo de acao cujos efeitos nos edificios exige a consideracao de duas componentes horizontais, o que tem exigencias mais severas nos pilares comparativamente a acao unidirecional. Assim, esta tese centra-se na avaliacao da resposta estrutural de pilares de betao armado sujeitos a acoes ciclicas horizontais biaxiais, em tres linhas principais. Em primeiro lugar desenvolveu-se uma campanha de ensaios para o estudo do comportamento ciclico uniaxial e biaxial de pilares de betao armado com esforco axial constante. Para tal foram construidas quatro series de pilares retangulares de betao armado (24 no total) com diferentes caracteristicas geometricas e quantidades de armadura longitudinal, tendo os pilares sido ensaiados para diferentes historias de carga. Os resultados experimentais obtidos sao analisados e discutidos dando particular atencao a evolucao do dano, a degradacao de rigidez e resistencia com o aumento das exigencias de deformacao, a energia dissipada, ao amortecimento viscoso equivalente; por fim e proposto um indice de dano para pilares solicitados biaxialmente. De seguida foram aplicadas diferentes estrategias de modelacao nao-linear para a representacao do comportamento biaxial dos pilares ensaiados, considerando nao-linearidade distribuida ao longo dos elementos ou concentrada nas extremidades dos mesmos. Os resultados obtidos com as varias estrategias de modelacao demonstraram representar adequadamente a resposta em termos das curvas envolventes forca-deslocamento, mas foram encontradas algumas dificuldades na representacao da degradacao de resistencia e na evolucao da energia dissipada. Por fim, e proposto um modelo global para a representacao do comportamento nao-linear em flexao de elementos de betao armado sujeitos a acoes biaxiais ciclicas. Este modelo tem por base um modelo uniaxial conhecido, combinado com uma funcao de interacao desenvolvida com base no modelo de Bouc- Wen. Esta funcao de interacao foi calibrada com recurso a tecnicas de otimizacao e usando resultados de uma serie de analises numericas com um modelo refinado. E ainda demonstrada a capacidade do modelo simplificado em reproduzir os resultados experimentais de ensaios biaxiais de pilares.

  13. Incorporation of hydrogel as a sensing medium for recycle of sensing material in chemical sensors

    NASA Astrophysics Data System (ADS)

    Hwang, Yunjung; Park, Jeong Yong; Kwon, Oh Seok; Joo, Seokwon; Lee, Chang-Soo; Bae, Joonwon

    2018-01-01

    A hydrogel, produced with agarose extracted from seaweed, was introduced as a reusable medium in ultrasensitive sensors employing conducting polymer nanomaterials and aptamers. A basic dopamine (DA) sensor was constructed by placing a hydrogel, containing a sensing material composed of aptamer-linked carboxylated polypyrrole nanotubes (PPy-COOH NTs), onto a micropatterned gold electrode. The hydrogel provided a benign electrochemical environment, facilitated specific interactions between DA and the PPy-COOH NT sensing material, and simplified the retrieval of PPy-COOH NTs after detection. It was demonstrated that the agarose hydrogel was successfully employed as a sensing medium for detection of DA, providing a benign environment for the electrode type sensor. PPy-COOH NTs were recovered by simply heating the hydrogel in water. The hydrogel also afforded stable signal intensity after repeated use with a limit of detection of 1 nmol and a clear, stable signal up to 100 nmol DA. This work provides relevant information for future research on reusable or recyclable sensors.

  14. The Moon Phases in a Paper Box. (Spanish Title: Las Fases de la Luna en Una Caja de Cartón.) As Fases da Lua Numa Caixa de Papelão

    NASA Astrophysics Data System (ADS)

    de Fátima O. Saraiva, Maria; Amador, Cláudio B.; Kemper, Érico; Goulart, Paulo; Muller, Angela

    2007-12-01

    We present a very simple concrete model to demonstrate the concept of phases of an illuminated body. The main objective of our model is to help the understanding of the Moon phases as viewed from the perspective of an observer on Earth. The material allows the visualization of two important effects: (1st) even though all the time half Moon is illuminated by the Sun, we see different fractions of the illuminated Moon surface, depending on our angle of sight; (2nd) the orientation of the convex part of the Moon in the crescent and waning phases on the sky also depends on our perspective from Earth. The use of a closed box allows one to see the contrast among the different phases with no need of a dark room. We also present a text on the Moon phases, emphasizing the dependence of the aspect of the bright part on the angle of sight. En este trabajo proponemos la construcción de material didáctico de bajo costo para demostración del concepto de fases de un cuerpo iluminado. El principal objetivo de nuestro material es facilitar la comprensión de las fases de la Luna desde la perspectiva de un observador en la Tierra. El material ayuda la visualización de dos efectos importantes: (1º) a pesar de tener siempre la mitad de la Luna (representada por una bolita de espuma plástica o de ping-pong), iluminada por el Sol ( representado por una fuente de luz natural o artificial), vemos diferentes fracciones de su superficie iluminada, dependiendo del ángulo por el cual la vemos; (2º) la orientación del borde convexo de la Luna en las fases Creciente y Menguante también depende de la perspectiva por la cual la miramos desde la Tierra. El uso de una caja cerrada permite observar el contraste entre las diferentes fases sin necesidad de estar en un recinto oscuro. Presentamos también un texto explicativo sobre las fases de la Luna, enfatizando la dependencia de la apariencia de la parte iluminada con el ángulo de visión. Neste trabalho propomos a construção de material didático de baixo custo para demonstração do conceito de fases de um corpo iluminado. O principal objetivo de nosso material é facilitar a compreensão das fases da Lua da perspectiva de um observador na Terra. O material ajuda na visualização de dois efeitos importantes: (1º) mesmo tendo sempre a metade da "Lua" (representada por uma bolinha de isopor ou de ping-pong) iluminada pelo "Sol" (representado por uma fonte de luz natural ou artificial), nós vemos diferentes frações de sua superfície iluminada, dependendo do ângulo pelo qual a olhamos; (2º) a orientação da borda convexa da Lua nas fases Crescente e Minguante também depende da perspectiva pela qual a olhamos da Terra. O uso de uma caixa fechada permite observar o contraste entre as diferentes fases sem necessidade de estar em uma sala escurecida. Apresentamos também um texto explicativo sobre fases da Lua, enfatizando a dependência da aparência da parte iluminada com o ângulo de visada.

  15. The study of the use of a latex biomembrane and conjunctival autograft in rabbit conjunctiva wound healing.

    PubMed

    Pinho, Erika Christina Canarim Martha de; Chahud, Fernando; Lachat, João-José; Coutinho-Netto, Joaquim José; Sousa, Sidney Julio Faria E

    2018-04-01

    RESUMO Objetivo: Estudar o uso da biomembrana de látex e o transplante conjuntival autólogo na cicatrização conjuntival em coelhos. Métodos: Em nove coelhos albinos, neo-zelandeses, machos foram removidas áreas retangulares idênticas, do quadrante supero nasal, adjacente ao limbo, de ambos os olhos. As áreas desnudas da camada esclerótica nos olhos direitos foram recobertas com biomembrana de látex e a dos olhos esquerdos com enxerto conjuntival autólogo. Os animais foram sacrificados em grupos de três, aos 7, 14 e 21 dias após a cirurgia. Os tecidos do local cirúrgico, incluindo a córnea, foram fixados em formaldeído, antes de serem processados em parafina e corados com hematoxilina e eosina. A natureza e a intensidade da resposta inflamatória e o padrão de epitelização da superfície conjuntival foram avaliados sob microscopia óptica, em seções histológicas longitudinais, passando pelo centro dos espécimes anatômicos. Resultados: Até o décimo quarto dia pós-operatório, o grupo que recebeu a biomembrana apresentou reação inflamatória mais intensa do que o grupo com auto enxerto conjuntival. Aos 14 dias, os olhos com biomembrana apresentavam-se menos inflamados e com estroma mais espesso do que aos 7 dias. Aos 21 dias, a reparação conjuntival de ambos os grupos apresentavam características semelhantes. Conclusão: Apesar de apresentar uma cicatrização mais lenta, a biomembrana de látex se mostrou tão eficaz quanto o auto enxerto conjuntival na reconstrução da superfície ocular após três semanas de cicatrização pós-operatória. Devido as suas baixas toxicidade e alergenicidade, este material parece ser uma opção terapêutica promissora na reconstrução da conjuntiva.ABSTRACT Purpose: To study a latex biomembrane and conjunctival autograft with regard to the promotion of conjunctival healing in rabbits. The study included nine male albino rabbits. In these rabbits, a rectangular area of the conjunctiva was surgically removed from the superonasal quadrant adjacent to the limbus in both eyes. The bare area of the sclerotic coat of the right eye was reconstructed with a latex biomembrane, and the corresponding site of the left eye was reconstructed with a conjunctival autograft. The animals were killed in groups of three at 7, 14, and 21 days after surgery. The tissues from the surgical site, including the cornea, were fixed in formaldehyde, and were then processed in paraffin and stained with hematoxylin and eosin. The nature and intensity of the inflammatory response and the epithelial pattern at the conjunctival surface were evaluated under optical microscopy with longitudinal histological sections through the center of the anatomical specimens. Until the 14th postoperative day, the inflammatory reaction was greater in the biomembrane group than in the conjunctival autograft group. In the latex biomembrane group, inflammation was less intense and the stroma was thicker on the 14th postoperative day than on the 7th postoperative day. After three weeks, conjunctival healing in both groups showed similar characteristics. Although healing was slower with a latex biomembrane, tissue reconstitution was almost the same as that with a conjunctival autograft by three weeks. A latex biomembrane is as effective as a conjunctival autograft for the reconstruction of the ocular surface. Owing to the lack of toxicity and allergenicity, a latex biomembrane appears to be a promising therapeutic option for conjunctival reconstruction.

  16. 33 CFR 322.1 - General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the review of applications for Department of the Army (DA) permits to authorize certain structures or... authorities of the DA. These include discharges of dredged or fill material into waters of the United States... Act of 1972, as amended (33 U.S.C. 1413; see 33 CFR part 324). A DA permit will also be required under...

  17. 33 CFR 323.1 - General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the review of applications for DA permits to authorize the discharge of dredged or fill material into... Harbors Act of 1899 (33 U.S.C. 403; see 33 CFR part 322). A DA permit will also be required under these... into waters of the United States. Applicants for DA permits under this part should refer to the other...

  18. Implementation of Microcalorimeter Array Technology for Safeguards of Nuclear Material

    NASA Astrophysics Data System (ADS)

    Kossmann, Shannon; Mateju, Klara; Koehler, Katrina; Croce, Mark

    2018-03-01

    Safeguards of nuclear materials depend on both destructive and nondestructive assay (DA and NDA, respectively). Ultra-high-resolution microcalorimeter gamma spectroscopy has the potential to substantially reduce the performance gap between NDA and DA methods in determination of plutonium isotopic composition. This paper details the setup of a cryostat and microwave readout system for microcalorimeter gamma spectroscopy, the functionality of which has been successfully demonstrated.

  19. Inguinodynia in patients submitted to conventional inguinal hernioplasty.

    PubMed

    Dias, Bruno Garcia; Santos, Marcelo Protásio Dos; Chaves, Ana Barbara DE Jesus; Willis, Mariana; Gomes, Marcio Couto; Andrade, Fernandes Tavares; Melo, Valdinaldo Aragão DE; Santos, Paulo Vicente Dos

    2017-01-01

    to evaluate the incidence of chronic pain and its impact on the quality of life of patients submitted to inguinal hernioplasty using the Lichtenstein technique. this was a descriptive, cross-sectional study of patients operated under spinal anesthesia from February 2013 to February 2015 and who had already completed six postoperative months. We questioned patients about the presence of chronic inguinal pain and, if confirmed, invited them to a consultation in which we assessed the pain and its impact on quality of life. out of 158 patients submitted to the procedure, we identified 7.6% as having inguinodynia. Of these, there was an impact on the quality of life in 25%. the incidence of inguinodynia after hernioplasty with repercussion in quality of life was similar to the one of found in the world literature. avaliar a incidência de dor crônica e o seu impacto na qualidade de vida de pacientes submetidos à hernioplastia inguinal pela técnica de Lichtenstein. trata-se de estudo transversal descritivo, de pacientes operados de hérnia inguinal pela técnica de Lichtenstein sob anestesia raquidiana, no período de fevereiro de 2013 a fevereiro de 2015, e que já haviam completado seis meses de pós-operatório. Os pacientes foram questionados sobre a presença de dor inguinal crônica e, caso confirmada, convidados a uma consulta na qual foi feita análise da qualidade da dor e seu impacto na qualidade de vida. do total de 158 pacientes submetidos ao procedimento, 7,6% foram identificados como portadores de inguinodinia. Destes, houve impacto na qualidade de vida em 25%. observou-se incidência de inguinodinia pós-hernioplastia com repercussão na qualidade de vida semelhante à literatura mundial.

  20. Use of DSC and DMA Techniques to Help Investigate a Material Anomaly for PTFE Used in Processing a Piston Cup for the Urine Processor Assembly (UPA) on International Space Station (ISS)

    NASA Technical Reports Server (NTRS)

    Wingard, Doug

    2010-01-01

    Human urine and flush water are eventually converted into drinking water with the Urine Processor Assembly (UPA) aboard the International Space Station (ISS). This conversion is made possible through the Distillation Assembly (DA) of the UPA. One component of the DA is a molded circular piston cup made of virgin polytetrafluoroethylene (PTFE). The piston cup is assembled to a titanium component using eight fasteners and washers. Molded PTFE produced for spare piston cups in the first quarter of 2010 was different in appearance and texture, and softer than material molded for previous cups. For the suspect newer PTFE material, cup fasteners were tightened to only one-half the required torque value, yet the washers embedded almost halfway into the material. The molded PTFE used in the DA piston cup should be Type II, based on AMS 3667D and ASTM D4894 specifications. The properties of molded PTFE are considerably different between Type I and II materials. Engineers working with the DA thought that if Type I PTFE was molded by mistake instead of Type II material, that could have resulted in the anomalous material properties. Typically, the vendor molds flat sheet PTFE from the same material lot used to mold the piston cups, and tensile testing as part of quality control should verify that the PTFE is Type II material. However, for this discrepant lot of material, such tensile data was not available. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) were two of the testing techniques used at the NASA/Marshall Space Flight Center (MSFC) to investigate the anomaly for the PTFE material. Other techniques used on PTFE specimens were: Shore D hardness testing, tensile testing on dog bone specimens and a qualitative estimation of porosity by optical and scanning electron microscopy.

  1. Preparation of Lanthanide-Polymer Composite Material via Click Chemistry.

    PubMed

    Chen, Bin; Wen, Guian; Wu, Jiajie; Feng, Jiachun

    2015-10-01

    Covalently attaching lanthanide complexes to the polymer backbone can effectively reduce the clustering of lanthanides and thus become an important strategy to fully unleash their potential. In this Communication, a metal-free click reaction is used for the first time to link a lanthanide complex to the polymer matrix. A diene-bearing copolymer with anthracenylmethyl methacrylate as a monomer and a dienophile-bearing lanthanide complex with 5-maleimido-1,10-phenanthroline as the second ligand are synthesized and coupled together through a Diels-Alder cycloaddition (DA). A comparative investigation demonstrates that the composite material prepared by DA click reaction shows the highest quantum yields in the same lanthanide concentration as compared to materials prepared by widely used "directly doping" and "in situ coordinating lanthanide ions with macromolecular ligand" approaches. This work suggests that the "metal-free" DA click reaction can be a promising tool in the synthesis of high efficient lanthanide functionalized polymeric materials. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Transferências orbitais dentro do modelo quase bicircular no sistema Terra-Lua-Sol

    NASA Astrophysics Data System (ADS)

    Corrêa, A. A.; de Almeida Prado, A. F. B.; Stuchi, T. J.; Beaugé, C.

    2003-08-01

    O problema quase bicircular planar consiste na determinação da dinâmica de um corpo, de massa desprezível, que se move sob o campo gravitacional de três corpos. No caso estudado, o quarto corpo é considerado um satélite artificial e os demais são a Terra, a Lua e o Sol, formando o sistema de três corpos. Este modelo permite a construção de uma hamiltoniana similar a do problema restrito de três corpos (PRTC), incluindo termos periódicos não autônomos, provenientes da presença do Sol, portanto pode ser entendido como uma perturbação ao PRTC. Suas órbitas periódicas aparecem isoladas e possuem o mesmo período solar. Os pontos de equilíbrio colineares possuem o mesmo caráter de estabilidade linear dos pontos lagrangianos (L1, L2 e L3) do PRTC, sendo do tipo sela x centro x centro, instável na direção x e estáveis nas direções y e z. As órbitas periódicas tridimensionais ao redor do ponto colinear é chamada órbita Halo. O objetivo deste trabalho é determinar órbitas de transferências de baixo consumo de combustível para um veículo espacial partindo de uma órbita de estacionamento ao redor da Terra em direção a uma órbita Halo do ponto L1, situado entre a Terra e Lua. Esta tarefa pode ser transformada no problema de valor de contorno: dado um ponto inicial na órbita de estacionamento, um ponto final na órbita halo e o tempo de transferência, deseja-se obter a trajetória que liga estes dois pontos e que minimize os incrementos de velocidade do veículo. Essas transferências são realizadas baseadas no método de Lambert e analisadas de modo a fornecer um baixo consumo. Posteriormente, é feita uma comparação de consumo com as órbitas de transferência equivalentes do PRTC.

  3. 2D Hexagonal Boron Nitride (2D-hBN) Explored for the Electrochemical Sensing of Dopamine.

    PubMed

    Khan, Aamar F; Brownson, Dale A C; Randviir, Edward P; Smith, Graham C; Banks, Craig E

    2016-10-04

    Crystalline 2D hexagonal boron nitride (2D-hBN) nanosheets are explored as a potential electrocatalyst toward the electroanalytical sensing of dopamine (DA). The 2D-hBN nanosheets are electrically wired via a drop-casting modification process onto a range of commercially available carbon supporting electrodes, including glassy carbon (GC), boron-doped diamond (BDD), and screen-printed graphitic electrodes (SPEs). 2D-hBN has not previously been explored toward the electrochemical detection/electrochemical sensing of DA. We critically evaluate the potential electrocatalytic performance of 2D-hBN modified electrodes, the effect of supporting carbon electrode platforms, and the effect of "mass coverage" (which is commonly neglected in the 2D material literature) toward the detection of DA. The response of 2D-hBN modified electrodes is found to be largely dependent upon the interaction between 2D-hBN and the underlying supporting electrode material. For example, in the case of SPEs, modification with 2D-hBN (324 ng) improves the electrochemical response, decreasing the electrochemical oxidation potential of DA by ∼90 mV compared to an unmodified SPE. Conversely, modification of a GC electrode with 2D-hBN (324 ng) resulted in an increased oxidation potential of DA by ∼80 mV when compared to the unmodified electrode. We explore the underlying mechanisms of the aforementioned examples and infer that electrode surface interactions and roughness factors are critical considerations. 2D-hBN is utilized toward the sensing of DA in the presence of the common interferents ascorbic acid (AA) and uric acid (UA). 2D-hBN is found to be an effective electrocatalyst in the simultaneous detection of DA and UA at both pH 5.0 and 7.4. The peak separations/resolution between DA and UA increases by ∼70 and 50 mV (at pH 5.0 and 7.4, respectively, when utilizing 108 ng of 2D-hBN) compared to unmodified SPEs, with a particularly favorable response evident in pH 5.0, giving rise to a significant increase in the peak current of DA. The limit of detection (3σ) is found to correspond to 0.65 μM for DA in the presence of UA. However, it is not possible to deconvolute the simultaneous detection of DA and AA. The observed electrocatalytic effect at 2D-hBN has not previously been reported in the literature when supported upon carbon or any other electrode. We provide valuable insights into the modifier-substrate interactions of this material, essential for those designing, fabricating, and consequently performing electrochemical experiments utilizing 2D-hBN and related 2D materials.

  4. dK/da effects on the SCC growth rates of nickel base alloys in high-temperature water

    NASA Astrophysics Data System (ADS)

    Chen, Kai; Wang, Jiamei; Du, Donghai; Andresen, Peter L.; Zhang, Lefu

    2018-05-01

    The effect of dK/da on crack growth behavior of nickel base alloys has been studied by conducting stress corrosion cracking tests under positive and negative dK/da loading conditions on Alloys 690, 600 and X-750 in high temperature water. Results indicate that positive dK/da accelerates the SCC growth rates, and the accelerating effect increases with dK/da and the initial CGR. The FRI model was found to underestimate the dK/da effect by ∼100X, especially for strain hardening materials, and this underscores the need for improved insight and models for crack tip strain rate. The effect of crack tip strain rate and dK/dt in particular can explain the dK/da accelerating effect.

  5. Molecular genetic analysis of activation-tagged transcription factors thought to be involved in photomorphogenesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Neff, Michael M.

    This is a final report for Department of Energy Grant No. DE-FG02-08ER15927 entitled “Molecular Genetic Analysis of Activation-Tagged Transcription Factors Thought to be Involved in Photomorphogenesis”. Based on our preliminary photobiological and genetic analysis of the sob1-D mutant, we hypothesized that OBP3 is a transcription factor involved in both phytochrome and cryptochrome-mediated signal transduction. In addition, we hypothesized that OBP3 is involved in auxin signaling and root development. Based on our preliminary photobiological and genetic analysis of the sob2-D mutant, we also hypothesized that a related gene, LEP, is involved in hormone signaling and seedling development.

  6. A estabilidade dos PAHS em função da energia da radiação interestelar nas faixas UV e raios-X

    NASA Astrophysics Data System (ADS)

    Pinotti, R.; Costa, R. K.; Boechat-Roberty, H. M.; Lago, A.; Souza, G. B.

    2003-08-01

    A nebulosa CRL 618, uma proto-nebulosa planetária cuja nuvem molecular espessa envolve uma estrela B0, contém uma grande quantidade de C2H2 e CH4. Estas moléculas são consideradas os tijolos da criação de grandes moléculas carbonadas como os Hidrocarbonetos Policíclicos Aromáticos (PAHs). Esta nebulosa, por estar exposta a intensos campos de UV e Raios-X, é uma região de fotodissociação molecular que propicia a formação de novas moléculas, confirmada pela presença de C4H2 e C6H6 (Benzeno), que é a unidade básica dos PAHs. Atribui-se a esta família de moléculas orgânicas duas propriedades fundamentais, a resistência para sobreviver ao campo de radiação UV interestelar e a geração das bandas de emissão não identificadas (UIR) observadas no infravermelho. No entanto, alguns autores questionam a resistência dos PAHs ao campo de radiação UV interestelar. Empregando a técnica de Espectrometria de Massas por Tempo de Vôo, no modo de coincidência fotoelétron-fotoíon, estudamos a ionização e fragmentação das seguintes moléculas: Benzeno, Benzeno deuterado, Naftaleno, Antraceno e Fenantreno. Utilizamos uma fonte de Hélio monocromática em 21,21 eV (584,5 Å) e a radiação Síncroton do Laboratório Nacional de Luz Síncroton (LNLS) em diferentes energias nas proximidades da borda do C 1s ( 290 eV). Comprovamos a estabilidade dos PAHs sob ação de UV (21,21 eV), onde eles apresentam um baixo nível de fotodissociação, produzindo fragmentos ionizados com rendimento total na ordem de 5 por cento em relação ao íon molecular pai. Entretanto, em altas energias, na faixa de Raios-X, a quebra destas moléculas torna-se mais intensa, com a produção de muitos fragmentos. Como uma das rotas de fragmentação do Naftaleno é [(C10H8) = > (C6H6+) + (C4H2) + (e-)], e como temos as evidências observacionais da existência do C4H2 e C6H6 na nebulosa CRL 618, sugerimos que este ambiente também possui o Naftaleno.

  7. Anderson localization in metamaterials with compositional disorder

    NASA Astrophysics Data System (ADS)

    Torres-Herrera, E. J.; Izrailev, F. M.; Makarov, N. M.

    2011-11-01

    We consider one-dimensional periodic-on-average bi-layered models with random perturbations in dielectric constants of both basic slabs composing the structure unit-cell. We show that when the thicknesses da and db of basic layers are essentially nonequal, da ≠ db, the localization length Lloc is described by the universal expression for two cases: (a) both layers are made from right-handed materials (the RH-RH model), (b) the a layers are of a right-handed material while the b layers are of a left-handed material (the RH-LH model). For these models the derived expression for Lloc includes all possible correlations between two disorders. However, when da = db the RH-LH model exhibits a highly nontrivial properties originated from inhomogeneous distribution of the phase of propagating wave, even in the case of white-noise disorder. We analytically show that in this case the localization length diverges in the conventional second order in perturbation parameters. Therefore, recently numerically discovered anomalies in Lloc are due to the next order of approximation. On the other hand, for the RH-RH model the general expression for Lloc remains valid for da = db as well.

  8. Airway disease in highway and tunnel construction workers exposed to silica.

    PubMed

    Oliver, L Christine; Miracle-McMahill, Heidi

    2006-12-01

    Construction workers employed in a unique type of tunnel construction known as tunnel jacking were exposed over an 18-month period to respirable crystalline silica at concentrations that exceeded the OSHA permissible exposure limit. The present study examines workplace exposures and occurrence of airway disease in these workers. Medical and occupational histories and chest radiographs were obtained on 343 active construction workers who had worked on the site during the period in question. Chest radiographs were interpreted according to the ILO-1980 system of classification. Standardized questions were used to develop an algorithm to define symptoms consistent with asthma (SCA) and to determine these respiratory outcomes: chronic bronchitis, shortness of breath (SOB), and physician-diagnosed asthma (current vs. not current). Relationships with each of three work activities were examined: slurry wall breakthrough (SWB), chipping caisson overpour, and tunneling/mining. Participants included laborers, carpenters, tunnel workers, ironworkers, operating engineers, and electricians. No cases of silicosis were found on chest X-ray. Overall prevalence of chronic bronchitis, SCA, SOB, and physician-diagnosed asthma was 10.7%, 25%, 29%, and 6.6%, respectively. Odds ratios (OR) for carpenters compared to laborers were significantly elevated for chronic bronchitis, SCA, and SOB. SWB was associated with chronic bronchitis and SCA (OR 4.93, 95% CI = 1.01, 24.17; OR 3.32, 95% CI = 1.25, 8.84, respectively). The interaction between SWB, SCA, and trade was significant for carpenters (OR 6.87, 95% CI = 1.66, 28.39). Inverse trends were observed for months on the site and chronic bronchitis, SCA, and SOB (P = 0.0374, 0.0006, and 0.0307, respectively). Tunnel construction workers exposed to respirable crystalline silica and cement dust are at increased risk for airway disease. Extent of risk varies by trade and work activity. Our data indicate the importance of bystander exposures and suggest that tunnel jacking may be associated with greater risk compared to more traditional methods of tunnel construction. A healthy worker effect is suggested.

  9. Facial skeleton asymmetry and its relationship to mastication in the Early Medieval period (Great Moravian Empire, Mikulčice, 9th-10th century).

    PubMed

    Ibrová, Alexandra; Dupej, Ján; Stránská, Petra; Velemínský, Petr; Poláček, Lumír; Velemínská, Jana

    2017-12-01

    The aim of this study was to analyse the relationship of mastication and directional asymmetry (DA) of upper facial skeleton in Early Medieval sample from the Mikulčice settlement (Czech Republic). The settlement is divided into two burial areas of presumably different socioeconomic status: the castle and the sub-castle. The material consisted of 193 individuals (125 castle, 68 sub-castle). The relationship of facial skeleton DA and mastication was analysed by examining tooth wear and mandibular shape by means of 3D geometric morphometrics. Tooth wear of premolars and molars was evaluated using appropriate scoring systems. 3D coordinates of 35 mandibular landmarks were scanned using MicroScribe G2X digitizing system. The results did not reveal any significant differences in tooth wear DA or mandible DA values between burial areas or sexes. Mandibular shape, however, differed significantly between burial areas and sexes. Directional changes of mandibular landmarks supported a right chewing side preference in the sample. Significant relationship between upper facial skeleton DA and mandible DA was recorded. Differences in subsistence between burial areas and sexes did not translate into differences in mandible DA and dental wear. However, mandibular shape analysis revealed prominence of areas affected by masticatory muscles in individuals from the castle. Higher consumption of tough material, such as meat, has been proposed as possible explanation. The right side was found to be preferential for chewing. The relationship between upper facial skeleton DA and mandible DA was concluded to be the result of the compensatory and adaptive function of mandible. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Analysis of suffering at work in Family Health Support Centers.

    PubMed

    Nascimento, Débora Dupas Gonçalves do; Oliveira, Maria Amélia de Campos

    2016-01-01

    Analyzing the work process in the Family Health Support Center. An exploratory, descriptive case study using a qualitative approach. Focus groups were conducted with 20 workers of a Family Health Support Center, and the empirical material was subjected to content analysis technique and analyzed in light of Work Psychodynamics. The category of suffering is presented herein as arising from the dialectical contradiction between actual work and prescribed work, from resistance to the Family Health Support Center's proposal and a lack of understanding of their role; due to an immediatist and curative culture of the users and the Family Health Strategy; of the profile, overload and identification with work. The dialectical contradiction between expectations from Family Health Strategy teams and the work in the Family Health Support Center compromises its execution and creates suffering for workers. Analisar o processo de trabalho no Núcleo de Apoio à Saúde da Família. Estudo de caso exploratório, descritivo e de abordagem qualitativa. Grupos focais foram realizados com 20 trabalhadores do Núcleo de Apoio à Saúde da Família, o material empírico foi submetido à técnica de análise de conteúdo e analisado à luz da Psicodinâmica do Trabalho. Apresenta-se aqui a categoria sofrimento que neste estudo decorre da contradição dialética entre o trabalho real e o trabalho prescrito, da resistência à proposta do Núcleo de Apoio à Saúde da Família e da falta de compreensão de seu papel; da cultura imediatista e curativa do usuário e da Estratégia Saúde da Família; do perfil, sobrecarga e identificação com o trabalho. A contradição dialética entre expectativas das equipes da Estratégia Saúde da Família e o trabalho no Núcleo de Apoio à Saúde da Família compromete sua efetivação e gera sofrimento aos trabalhadores.

  11. The development of communication skills and the teacher's performance in the nursing student's perspective.

    PubMed

    Oliveira, Karime Rodrigues Emilio de; Braga, Eliana Mara

    2016-06-01

    To understand experiences in the development of communication skills and the teacher's role in this teaching-learning process under the perspective of undergraduate nursing students by considering two types of curriculum organization. Descriptive study with a qualitative approach conducted in two public schools located in São Paulo state, Brazil. Data were collected by means of self-completed forms from 81 students in the second and fourth years of the undergraduate program. Results were analyzed in light of Content Analysis. Results showed that the development of such skills is related to: students' individual characteristics, patients' characteristics, those of the health-disease process, the health-care team's profile and the theoretical knowledge acquired on communication in health-care provision and nursing. The teacher's role was perceived as one that supports and encourages interactions with patients and health-care teams by teaching and providing orientation about interpersonal communication. Students identify and value the importance of their teachers' performance in the development and acquisition of communication skills. Additionally, students who experience active teaching-learning methodologies acknowledge the teacher as essential to provide opportunities for students to express their knowledge and thoughts. Compreender, sob a ótica de graduandos de enfermagem, as experiências no desenvolvimento de habilidades comunicativas e a atuação do professor neste processo de ensino-aprendizagem, considerando dois tipos de organização curricular. Pesquisa descritiva com abordagem qualitativa, realizada em duas instituições de ensino públicas, situadas no interior do estado de São Paulo, Brasil. A coleta dos dados foi realizada pelo autopreenchimento de formulário por 81 alunos de segundo e quartos anos da graduação. Os resultados foram analisados à luz da Análise de Conteúdo. Revelaram que o desenvolvimento desta habilidade está relacionado à: características individuais dos alunos, dos pacientes, do processo saúde-doença, perfil da equipe e dos conhecimentos teóricos sobre comunicação em saúde e em enfermagem. O papel do professor foi percebido apoiando e incentivando as interações com pacientes e equipes de saúde e ensinando e orientando sobre comunicação interpessoal. Os alunos identificam e valorizam a importância da atuação de seus professores no desenvolvimento e aquisição de habilidades comunicativas. Além disso, os estudantes que vivenciaram as metodologias ativas de ensino-aprendizagem reconhecem o docente essencial para oportunizar a expressão de conhecimentos e pensamentos dos alunos.

  12. A targeted drug delivery system based on dopamine functionalized nano graphene oxide

    NASA Astrophysics Data System (ADS)

    Masoudipour, Elham; Kashanian, Soheila; Maleki, Nasim

    2017-01-01

    The cellular targeting property of a biocompatible drug delivery system can widely increase the therapeutic effect against various diseases. Here, we report a dopamine conjugated nano graphene oxide (DA-nGO) carrier for cellular delivery of the anticancer drug, Methotrexate (MTX) into DA receptor positive human breast adenocarcinoma cell line. The material was characterized using scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy and UV-vis spectroscopy. Furthermore, the antineoplastic action of MTX loaded DA-nGO against DA receptor positive and negative cell lines were explored. The results presented in this article demonstrated that the application of DA functionalized GO as a targeting drug carrier can improve the drug delivery efficacy for DA receptor positive cancer cell lines and promise future designing of carrier conjugates based on it.

  13. Opto-Electronic and Interconnects Hierarchical Design Automation System (OE-IDEAS)

    DTIC Science & Technology

    2004-05-01

    NETBOOK WEBSITE............................................................71 8.2 SIMULATION OF CRITICAL PATH FROM THE MAYO “10G” SYSTEM MCM BOARD...Benchmarks from the DaVinci Netbook website In May 2002, CFDRC downloaded all the materials from the DaVinci Netbook website containing the benchmark

  14. Immunoblot patterns of Taenia asiatica taeniasis.

    PubMed

    Jeon, Hyeong-Kyu; Eom, Keeseon S

    2009-03-01

    Differential diagnosis of Taenia asiatica infection from other human taeniases by serology has been tested. An enzyme-linked immunoelectrotransfer blot (EITB) was applied to subjected human sera and tapeworm materials. Thirty-eight proteins reactive to serum IgG were observed between 121 and 10 kDa in adult worms, and more than 22 serum-reactive components between 97 kDa and 21.5 kDa were observed in eggs of T. asiatica. Antigens of adult T. asiatica revealed immunoblot bands between 120 and 21.5 kDa against T. asiatica infected sera. Antigens of adult Taenia saginata revealed 110-100, 66, 58-56, and 46 kDa immunoblot bands against T. asiatica infected sera. Antigens of adult Taenia solium also revealed 99-97, 68-66, and 46 kDa bands against T. asiatica infected sera. The immunoblot band of 21.5 kDa exhibited specificity to T. asiatica.

  15. Immunoblot Patterns of Taenia asiatica Taeniasis

    PubMed Central

    Jeon, Hyeong-Kyu

    2009-01-01

    Differential diagnosis of Taenia asiatica infection from other human taeniases by serology has been tested. An enzyme-linked immunoelectrotransfer blot (EITB) was applied to subjected human sera and tapeworm materials. Thirty-eight proteins reactive to serum IgG were observed between 121 and 10 kDa in adult worms, and more than 22 serum-reactive components between 97 kDa and 21.5 kDa were observed in eggs of T. asiatica. Antigens of adult T. asiatica revealed immunoblot bands between 120 and 21.5 kDa against T. asiatica infected sera. Antigens of adult Taenia saginata revealed 110-100, 66, 58-56, and 46 kDa immunoblot bands against T. asiatica infected sera. Antigens of adult Taenia solium also revealed 99-97, 68-66, and 46 kDa bands against T. asiatica infected sera. The immunoblot band of 21.5 kDa exhibited specificity to T. asiatica. PMID:19290097

  16. Influence of variable selection on partial least squares discriminant analysis models for explosive residue classification

    NASA Astrophysics Data System (ADS)

    De Lucia, Frank C., Jr.; Gottfried, Jennifer L.

    2011-02-01

    Using a series of thirteen organic materials that includes novel high-nitrogen energetic materials, conventional organic military explosives, and benign organic materials, we have demonstrated the importance of variable selection for maximizing residue discrimination with partial least squares discriminant analysis (PLS-DA). We built several PLS-DA models using different variable sets based on laser induced breakdown spectroscopy (LIBS) spectra of the organic residues on an aluminum substrate under an argon atmosphere. The model classification results for each sample are presented and the influence of the variables on these results is discussed. We found that using the whole spectra as the data input for the PLS-DA model gave the best results. However, variables due to the surrounding atmosphere and the substrate contribute to discrimination when the whole spectra are used, indicating this may not be the most robust model. Further iterative testing with additional validation data sets is necessary to determine the most robust model.

  17. Reactivity of long chain alkylamines to lignin moieties: implications on hydrophobicity of lignocellulose materials.

    PubMed

    Kudanga, Tukayi; Prasetyo, Endry Nugroho; Sipilä, Jussi; Guebitz, Georg M; Nyanhongo, Gibson S

    2010-08-20

    Enzymatic processes provide new perspectives for modification of lignocellulose materials. In the current study, laccase catalyzed coupling of long chain alkylamines to lignin model molecules and lignocellulose was investigated. Up to two molecules of dodecylamine (DA) and dihexylamine (DHA) were successfully coupled with lignin monomers (guaiacol, catechol and ferulic acid) while coupling onto complex lignin model compounds (syringylglycerol beta-guaiacyl ether, guaiacylglycerol beta-guaiacyl ether and dibenzodioxocin) yielded 1:1 coupling products. Surface analysis of beech veneers enzymatically grafted with DA showed an increase in nitrogen content of 3.18% compared to 0.71% in laccase only treated controls while the O/C ratio decreased from 0.52 to 0.46. Concomitantly the grafting of DHA or DA onto beech veneers resulted in a 53.8% and 84.2% increase in hydrophobicity, respectively when compared to simple adsorption. Therefore, laccase-mediated grafting of long chain alkylamines onto lignocellulose materials can be potentially exploited for improving their hydrophobicity. Copyright 2010 Elsevier B.V. All rights reserved.

  18. Model-Based Feasibility Assessment of Membrane Biofilm Reactor to Achieve Simultaneous Ammonium, Dissolved Methane, and Sulfide Removal from Anaerobic Digestion Liquor

    PubMed Central

    Chen, Xueming; Liu, Yiwen; Peng, Lai; Yuan, Zhiguo; Ni, Bing-Jie

    2016-01-01

    In this study, the membrane biofilm reactor (MBfR) is proposed to achieve simultaneous removal of ammonium, dissolved methane, and sulfide from main-stream and side-stream anaerobic digestion liquors. To avoid dissolved methane stripping, oxygen is introduced through gas-permeable membranes, which also from the substratum for the growth of a biofilm likely comprising ammonium oxidizing bacteria (AOB), anaerobic ammonium oxidation (Anammox) bacteria, denitrifying anaerobic methane oxidation (DAMO) microorganisms, aerobic methane oxidizing bacteria (MOB), and sulfur oxidizing bacteria (SOB). A mathematical model is developed and applied to assess the feasibility of such a system and the associated microbial community structure under different operational conditions. The simulation studies demonstrate the feasibility of achieving high-level (>97.0%), simultaneous removal of ammonium, dissolved methane, and sulfide in the MBfRs from both main-stream and side-stream anaerobic digestion liquors through adjusting the influent surface loading (or hydraulic retention time (HRT)) and the oxygen surface loading. The optimal HRT was found to be inversely proportional to the corresponding oxygen surface loading. Under the optimal operational conditions, AOB, DAMO bacteria, MOB, and SOB dominate the biofilm of the main-stream MBfR, while AOB, Anammox bacteria, DAMO bacteria, and SOB coexist in the side-stream MBfR to remove ammonium, dissolved methane, and sulfide simultaneously. PMID:27112502

  19. Teaching astronomy mediated by information and communication technologies: a preliminary approach

    NASA Astrophysics Data System (ADS)

    Rosa, R. H. L.; Voelzke, M. R.

    2014-08-01

    O presente trabalho é parte preliminar de um estudo mais amplo em nível de doutorado sobre o ensino de astronomia mediado pelas tecnologias da informação e comunicação, utilizando dispositivos compactos, móveis e pessoais. Este estudo também faz parte do projeto institucional do CEFETMG sobre ambientes diversificados de aprendizagem sob fomento da agência estadual FAPEMIG (Fundação de Amparo à Pesquisa do Estado de Minas Gerais). Esta apresentação aborda o resultado das concepções prévias de estudantes em relação a conhecimentos básicos de astronomia, ligados à percepção e observação direta do céu. Três turmas de estudantes de 1ª série e uma turma de 3ª série do ensino integrado médio técnico da Educação Básica, Técnica e Tecnológica (EBTT) do CEFETMG Campus II - Belo Horizonte/MG foram submetidas a uma avaliação prévia através de questionário estruturado. Este questionário foi elaborado de forma a abordar a percepção dos estudantes em relação aos recursos gráficos (figuras e desenhos) representativos de conhecimentos básicos de astronomia, comuns em livros didáticos. Após a análise dos resultados desta avaliação, organizou-se uma estratégia de intervenção didática em sala de aula sobre o conteúdo de astronomia, utilizando-se de recursos de mediação baseados nas tecnologias da informação e comunicação. Os temas selecionados para esta estratégia didática foram relacionados aos assuntos básicos de astronomia em que ocorreu maior nível de desconhecimento dos estudantes. Os estudantes foram submetidos a avaliação posterior elaborada com os mesmos pressupostos da avaliação prévia. A análise dos resultados foi realizada a partir dos pressupostos da aprendizagem significativa (Ausubel; Novak e Hanesian, 1983). O ensino de astronomia por mediação das tecnologias da informação e comunicação indica uma alternativa preliminar aos trabalhos de campo usuais orientados na prática escolar, tais como, visita a planetários e a observatórios. Os estudantes ficaram muito sensibilizados pela possibilidade de percepção do céu em tempo real e à luz do dia dentro da sala de aula no contexto escolar. Os resultados deste levantamento preliminar indicam que os níveis de ensino fundamental e médio não foram capazes de internalizar conhecimentos básicos de astronomia, a despeito das orientações específicas contidas nos documentos oficiais da educação básica brasileira (Brasil, 1997 e 2000). Os estudantes pesquisados apresentaram conhecimentos e concepções rudimentares sobre o tema astronomia básica, indicando a ausência de abordagem do tema astronomia, tampouco de observação direta do céu em trabalhos de campo escolares na educação básica. Finalmente, esta abordagem didática suscitou nos estudantes grande interesse para futuros trabalhos de observação de campo. D.P. Ausubel; J.D. Novak; H. Hanesian. Psicología Educativa: un punto de vista cognoscitivo. México: Trillas, 1983. BRASIL. Secretaria de Educação Básica. Parâmetros Curriculares Nacionais: Ensino Fundamental (PCN), 1997, e Ensino Médio (PCNEM), 2000. Brasília. MEC/SEB.

  20. Metagenomic analysis of a desulphurisation system used to treat biogas from vinasse methanisation.

    PubMed

    Dias, Marcela França; Colturato, Luis Felipe; de Oliveira, João Paulo; Leite, Laura Rabelo; Oliveira, Guilherme; Chernicharo, Carlos Augusto; de Araújo, Juliana Calabria

    2016-04-01

    We investigated the response of microbial community to changes in H2S loading rate in a microaerated desulphurisation system treating biogas from vinasse methanisation. H2S removal efficiency was high, and both COD and DO seemed to be important parameters to biomass activity. DGGE analysis retrieved sequences of sulphide-oxidising bacteria (SOB), such as Thioalkalimicrobium sp. Deep sequencing analysis revealed that the microbial community was complex and remained constant throughout the experiment. Most sequences belonged to Firmicutes and Proteobacteria, and, to a lesser extent, Bacteroidetes, Chloroflexi, and Synergistetes. Despite the high sulphide removal efficiency, the abundance of the taxa of SOB was low, and was negatively affected by the high sulphide loading rate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. STRESS AND FAILURE ANALYSIS OF RAPIDLY ROTATING ASTEROID (29075) 1950 DA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hirabayashi, Masatoshi; Scheeres, Daniel J., E-mail: masatoshi.hirabayashi@colorado.edu

    Rozitis et al. recently reported that near-Earth asteroid (29075) 1950 DA, whose bulk density ranges from 1.0 g cm{sup –3} to 2.4 g cm{sup –3}, is a rubble pile and requires a cohesive strength of at least 44-76 Pa to keep from failing due to its fast spin period. Since their technique for giving failure conditions required the averaged stress over the whole volume, it discarded information about the asteroid's failure mode and internal stress condition. This paper develops a finite element model and revisits the stress and failure analysis of 1950 DA. For the modeling, we do not consider material hardening andmore » softening. Under the assumption of an associated flow rule and uniform material distribution, we identify the deformation process of 1950 DA when its constant cohesion reaches the lowest value that keeps its current shape. The results show that to avoid structural failure the internal core requires a cohesive strength of at least 75-85 Pa. It suggests that for the failure mode of this body, the internal core first fails structurally, followed by the surface region. This implies that if cohesion is constant over the whole volume, the equatorial ridge of 1950 DA results from a material flow going outward along the equatorial plane in the internal core, but not from a landslide as has been hypothesized. This has additional implications for the likely density of the interior of the body.« less

  2. Characterization and quantification of N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine biocide by NMR, HPLC/MS and titration techniques.

    PubMed

    Mondin, Andrea; Bogialli, Sara; Venzo, Alfonso; Favaro, Gabriella; Badocco, Denis; Pastore, Paolo

    2014-01-01

    The present paper reports the determination of the tri-amine N-(3-aminopropyl)-N-dodecyl-1,3-propanediamine (TA) present in a raw material called LONZABAC used to formulate various, widely used commercial biocides. The active principle, TA, is present in LONZABAC together with other molecules at lower concentration levels. Three independent analytical approaches, namely solution NMR spectroscopy, liquid chromatography coupled to high resolution mass spectrometry (LC/HRMS) and acid-base titration in mixed solvent, were used to overcome the problem of the non-availability of the active principle as high purity standard. NMR analysis of raw material, using a suitable internal standard, evidenced in all analyzed lots the presence of the active principle, the N-dodecyl-1,3-propanediamine (DA) and the n-dodecylamine (MA) and the absence of non-organic, NMR-inactive species. NMR peak integration led to a rough composition of the MA:DA:TA as 1:9:90. The LC/HRMS analysis allowed the accurate determination of DA and MA and confirmed in all samples the presence of the TA, which was estimated by difference: MA=1.4±0.3%, DA=11.1±0.7%, TA=87.5±1.3%. The obtained results were used to setup an easy, rapid and cheap acid-base titration method able to furnish a sufficiently accurate evaluation of the active principle both in the raw material and in diluted commercial products. For the raw material the results were: TA+MA=91.1±0.8% and DA-MA=8.9±0.8%, statistically coherent with LC/MS ones. The LC/MS approach demonstrated also its great potentialities to recognize trace of the biocide components both in environmental samples and in the formulated commercial products. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Simultaneous determination of ascorbic acid, dopamine and uric acid by a novel electrochemical sensor based on N2/Ar RF plasma assisted graphene nanosheets/graphene nanoribbons.

    PubMed

    Jothi, Lavanya; Neogi, Sudarsan; Jaganathan, Saravana Kumar; Nageswaran, Gomathi

    2018-05-15

    A novel nitrogen/argon (N 2 /Ar) radio frequency (RF) plasma functionalized graphene nanosheet/graphene nanoribbon (GS/GNR) hybrid material (N 2 /Ar/GS/GNR) was developed for simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA). Various nitrogen mites introduced into GS/GNR hybrid structure was evidenced by a detailed microscopic, spectroscopic and surface area analysis. Owing to the unique structure and properties originating from the enhanced surface area, nitrogen functional groups and defects introduced on both the basal and edges, N 2 /Ar/GS/GNR/GCE showed high electrocatalytic activity for the electrochemical oxidations of AA, DA, and UA with the respective lowest detection limits of 5.3, 2.5 and 5.7 nM and peak-to-peak separation potential (ΔE P ) (vs Ag/AgCl) in DPV of 220, 152 and 372 mV for AA/DA, DA/UA and AA/UA respectively. Moreover, the selectivity, stability, repeatability and excellent performance in real time application of the fabricated N 2 /Ar/GS/GNR/GCE electrode suggests that it can be considered as a potential electrode material for simultaneous detection of AA, DA, and UA. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. The DaVinci Project: Multimedia in Art and Chemistry.

    ERIC Educational Resources Information Center

    Simonson, Michael; Schlosser, Charles

    1998-01-01

    Provides an overview of the DaVinci Project, a collaboration of students, teachers, and researchers in chemistry and art to develop multimedia materials for grades 3-12 visualizing basic concepts in chemistry and visual art. Topics addressed include standards in art and science; the conceptual framework for the project; and project goals,…

  5. Molecular Grafting of Fluorinated and Nonfluorinated Alkylsiloxanes on Various Ceramic Membrane Surfaces for the Removal of Volatile Organic Compounds Applying Vacuum Membrane Distillation.

    PubMed

    Kujawa, Joanna; Al-Gharabli, Samer; Kujawski, Wojciech; Knozowska, Katarzyna

    2017-02-22

    Four main tasks were presented: (i) ceramic membrane functionalization (TiO 2 5 kDa and 300 kDa), (ii) extended material characterization (physicochemistry and tribology) of pristine and modified ceramic samples, (iii) evaluation of chemical and mechanical stability, and finally (iv) assessment of membrane efficiency in vacuum membrane distillation applied for volatile organic compounds (VOCs) removal from water. Highly efficient molecular grafting with four types of perfluoroalkylsilanes and one nonfluorinated agent was developed. Materials with controllable tribological and physicochemical properties were achieved. The most meaningful finding is associated with the applicability of fluorinated and nonfluorinated grafting agents. The results of contact angle, hysteresis of contact angle, sliding angle, and critical surface tension as well as Young's modulus, nanohardness, and adhesion force for grafting by these two modifiers are comparable. This provides insight into the potential applicability of environmental friendly hydrophobic and superhydrophobic surfaces. The achieved hydrophobic membranes were very effective in the removal of VOCs (butanol, methyl-tert-butyl ether, and ethyl acetate) from binary aqueous solutions in vacuum membrane distillation. The correlation between membrane effectiveness and separated solvent polarity was compared in terms of material properties and resistance to the wetting (kinetics of wetting and in-depth liquid penetration). Material properties were interpreted considering Zisman theory and using Kao diagram. The significant influence of surface chemistry on the membrane performance was noticed (5 kDa, influence of hydrophobic nanolayer and separation controlled by solution-diffusion model; 300 kDa, no impact of surface chemistry and separation controlled by liquid-vapor equilibrium).

  6. Telephone screening for mild cognitive impairment in hispanics using the Alzheimer's questionnaire.

    PubMed

    Salazar, Ricardo; Velez, Carlos E; Royall, Donald R

    2014-01-01

    BACKGROUND/STUDY CONTEXT: There is a need for a simple and reliable screening test to detect individuals with mild cognitive impairment (MCI). The authors analyzed the relationship between performance of the Alzheimer's Questionnaire (AQ), an informant-rated measure of dementia-related behaviors, relative to the Telephone Interview for Cognitive Status-modified (TICS-m), Memory Impairment Scale-telephone version (MIS-t), and the Telephone Executive Assessment (TEXAS) as predictors of MCI. Comparative cross-sectional design, with data collected from participants in the Texas Alzheimer's Research and Care Consortium's (TARCC) San Antonio site. One-hundred percent of our sample was Hispanic. The San Antonio subset of TARCC sample is highly enriched with Mexican Americans (MAs). Fifty-five percent of the interviews were conducted in Spanish. Of the 184 persons enrolled, 124 were normal controls (NCs), and 60 participants had MCI. MCI status and Clinical Dementia Rating Scale Sum of Boxes (CDR-SOB) were determined through clinical consensus and performed blind to telephone assessments. Controlling for age, gender, education, and language of interview, the association between telephone measures and CDR-SOB was evaluated by multivariate regression. AQ scores were not affected by education, gender, and language of interview, but subject's age did show a positive correlation with informant AQ ratings. The AQ predicted CDR-SOB independently of the cognitive measures, adding variance above and beyond demographics. The TICS-m and the TEXAS appear to have additive value in improving the detection of cognitively impaired patients. The MIS-t failed to contribute significantly to CDR-SOB, independent of the other measures. The AQ may have utility as a culture-fair telephone screening for MCI. The AQ was able to modestly distinguish MCI from NCs. The TEXAS adds variance to a model of dementia severity independent of the AQ, suggesting that the latter may weakly assess that cognitive domain (executive control function). On the other hand, the AQ attenuates the MIS-t effect. This suggests a prominent AQ bias in favor of detecting memory impairment. Additional studies are required to determine if the AQ can distinguish between amnestic and dysexecutive MCI subtypes, or between MCI and Alzheimer's disease in Hispanics.

  7. Geriatric care: ways and means of providing comfort.

    PubMed

    Ribeiro, Patricia Cruz Pontifice Sousa Valente; Marques, Rita Margarida Dourado; Ribeiro, Marta Pontifice

    2017-01-01

    To know the ways and means of comfort perceived by the older adults hospitalized in a medical service. Ethnographic study with a qualitative approach. We conducted semi-structured interviews with 22 older adults and participant observation of care situations. The ways and means of providing comfort are centered on strategies for promoting care mobilized by nurses and recognized by patients(clarifying/informing, positive interaction/communication, music therapy, touch, smile, unconditional presence, empathy/proximity relationship, integrating the older adult or the family as partner in the care, relief of discomfort through massage/mobilization/therapy) and on particular moments of comfort (the first contact, the moment of personal hygiene, and the visit of the family), which constitute the foundation of care/comfort. Geriatric care is built on the relationship that is established and complete with meaning, and is based on the meeting/interaction between the actors under the influence of the context in which they are inserted. The different ways and means of providing comfort aim to facilitate/increase care, relieve discomfort and/or invest in potential comfort. Conhecer os modos e formas de confortar percecionadas pelos idosos hospitalizados num serviço de medicina. Estudo etnográfico com abordagem qualitativa. Realizamos entrevistas semiestruturadas com 22 doentes idosos e observação participante nas situações de cuidados. Os modos e formas de confortar centram-se em estratégias promotoras de conforto mobilizadas pelo enfermeiro e reconhecidas pelos doentes (informação/esclarecimento, interação/comunicação positiva, toque, sorriso, presença incondicional, integração do idoso/família nos cuidados e o alívio de desconfortos através da massagem/mobilização/terapêutica) e em momentos particulares de conforto (contato inaugural, visita da família., cuidados de higiene e arranjo pessoal), que se constituem como alicerces do cuidar/cuidado confortador. O cuidado geriátrico edifica-se na relação que se desenvolve, atribuída de sentido, e assenta-se num encontro/interação entre os atores sob influência do contexto em que está inserido. Os diferentes modos e formas de confortar objetivam facilitar/aumentar o conforto, aliviar o desconforto e/ou investir no conforto potencial.

  8. Diferentes Metodologias Aplicadas ao Ensino de Astronomia

    NASA Astrophysics Data System (ADS)

    Albrecht, E.; Voelzke, M. R.

    2007-08-01

    Espera-se que o educando ao final da educação básica, adquira uma compreensão atualizada das hipóteses, modelos e formas de investigação sobre a origem e evolução do Universo em que vive. O presente trabalho tem como principal objetivo compreender dentre três práticas pedagógicas adotadas no Ensino de Astronomia, na terceira série do Ensino Médio, da Escola Estadual Colônia dos Pescadores, qual melhor cumpre o papel de formação e aprendizagem para vida. A pesquisa preliminar foi através de um questionário onde o intuito foi diagnosticar o conhecimento já existente acerca do tema em questão. O questionário é composto de vinte questões dissertativas e objetivas, onde os educandos das três turmas envolvidas o responderam. Este trabalho utiliza as seguintes metodologias: a tradicional, onde o professor é um repassador de informações, fazendo uso exclusivo de lousa e giz; a segunda também de forma tradicional, porém com auxílio de multimídia para desenvolvimento das aulas e aterceira sob forma de seminários, elaborados e apresentados pelos educandos, no qual o educador faz apenas as intervenções necessárias. Ao final do trabalho os alunos responderão novamente o questionário inicial para diagnosticar dentre as três metodologias utilizadas qual apresentou melhor resultado. Os resultados preliminares obtidos, já podem ser observados e, dos 119 alunos entrevistados, as respostas obtidas são as mais diversas e evidenciam que a grande maioria nunca teve em sua vida escolar o tema Astronomia. Ao serem questionados se já haviam estudado Astronomia as respostas foram: turma A: sim 43%; turma B: sim: 21%; turma C: sim: 24%. Porém quando questionados a respeito do significado de Astronomia observou-se que: turma A: 100% de acertos; turma B: 64% acertos; turma C: 84% de acertos, demonstrando claramente a aprendizagem em diferentes esferas, não dependendo unicamente da escola. Até o presente momento, verificou-se que há interesse em estudar o tema Astronom! ia entre os educandos.

  9. 32 CFR 643.22 - Policy-Public safety: Requirement for early identification of lands containing dangerous materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... identification of lands containing dangerous materials. 643.22 Section 643.22 National Defense Department of...—Public safety: Requirement for early identification of lands containing dangerous materials. (a) DA will... lands by explosives, military chemical or other dangerous materials. (c) Procedures with respect to...

  10. 32 CFR 643.22 - Policy-Public safety: Requirement for early identification of lands containing dangerous materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... identification of lands containing dangerous materials. 643.22 Section 643.22 National Defense Department of...—Public safety: Requirement for early identification of lands containing dangerous materials. (a) DA will... lands by explosives, military chemical or other dangerous materials. (c) Procedures with respect to...

  11. 32 CFR 643.22 - Policy-Public safety: Requirement for early identification of lands containing dangerous materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... identification of lands containing dangerous materials. 643.22 Section 643.22 National Defense Department of...—Public safety: Requirement for early identification of lands containing dangerous materials. (a) DA will... lands by explosives, military chemical or other dangerous materials. (c) Procedures with respect to...

  12. Proteomic analysis of seed storage proteins in wild rice species of the Oryza genus.

    PubMed

    Jiang, Chunmiao; Cheng, Zaiquan; Zhang, Cheng; Yu, Tengqiong; Zhong, Qiaofang; Shen, J Qingxi; Huang, Xingqi

    2014-01-01

    The total protein contents of rice seeds are significantly higher in the three wild rice species (Oryza rufipogon Grill., Oryza officinalis Wall. and Oryza meyeriana Baill.) than in the cultivated rice (Oryza sativa L.). However, there is still no report regarding a systematic proteomic analysis of seed proteins in the wild rice species. Also, the relationship between the contents of seed total proteins and rice nutritional quality has not been thoroughly investigated. The total seed protein contents, especially the glutelin contents, of the three wild rice species were higher than those of the two cultivated rice materials. Based on the protein banding patterns of SDS-PAGE, O. rufipogon was similar to the two cultivated rice materials, followed by O. officinalis, while O. meyeriana exhibited notable differences. Interestingly, O. meyeriana had high contents of glutelin and low contents of prolamine, and lacked 26 kDa globulin band and appeared a new 28 kDa protein band. However, for O. officinali a 16 kDa protein band was absent and a row of unique 32 kDa proteins appeared. In addition, we found that 13 kDa prolamine band disappeared while special 14 kDa and 12 kDa protein bands were present in O. officinalis. Two-dimensional gel electrophoresis (2-DE) analysis revealed remarkable differences in protein profiles of the wild rice species and the two cultivated rice materials. Also, the numbers of detected protein spots of the three wild rice species were significantly higher than those of two cultivated rice. A total of 35 differential protein spots were found for glutelin acidic subunits, glutelin precursors and glutelin basic subunits in wild rice species. Among those, 18 protein spots were specific and 17 major spots were elevated. Six differential protein spots for glutelin acidic subunits were identified, including a glutelin type-A 2 precursor and five hypothetical proteins. This was the first report on proteomic analysis of the three wild rice species. Overall results suggest that there were many new types of glutelin subunits and precursor in the three wild rice species. Hence, wild rice species are important genetic resources for improving nutritional quality to rice.

  13. Electrochemical dopamine sensor based on P-doped graphene: Highly active metal-free catalyst and metal catalyst support.

    PubMed

    Chu, Ke; Wang, Fan; Zhao, Xiao-Lin; Wang, Xin-Wei; Tian, Ye

    2017-12-01

    Heteroatom doping is an effective strategy to enhance the catalytic activity of graphene and its hybrid materials. Despite a growing interest of P-doped graphene (P-G) in energy storage/generation applications, P-G has rarely been investigated for electrochemical sensing. Herein, we reported the employment of P-G as both metal-free catalyst and metal catalyst support for electrochemical detection of dopamine (DA). As a metal-free catalyst, P-G exhibited prominent DA sensing performances due to the important role of P doping in improving the electrocatalytic activity of graphene toward DA oxidation. Furthermore, P-G could be an efficient supporting material for loading Au nanoparticles, and resulting Au/P-G hybrid showed a dramatically enhanced electrocatalytic activity and extraordinary sensing performances with a wide linear range of 0.1-180μM and a low detection limit of 0.002μM. All these results demonstrated that P-G might be a very promising electrode material for electrochemical sensor applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Morphology-dependent Electrochemical Enhancements of Porous Carbon as Sensitive Determination Platform for Ascorbic Acid, Dopamine and Uric Acid

    NASA Astrophysics Data System (ADS)

    Cheng, Qin; Ji, Liudi; Wu, Kangbing; Zhang, Weikang

    2016-02-01

    Using starch as the carbon precursor and different-sized ZnO naoparticles as the hard template, a series of porous carbon materials for electrochemical sensing were prepared. Experiments of scanning electron microscopy, transmission electron microscopy and Nitrogen adsorption-desorption isotherms reveal that the particle size of ZnO has big impacts on the porous morphology and surface area of the resulting carbon materials. Through ultrasonic dispersion of porous carbon and subsequent solvent evaporation, different sensing interfaces were constructed on the surface of glassy carbon electrode (GCE). The electrochemical behaviors of ascorbic acid (AA), dopamine (DA) and uric acid (UA) were studied. On the surface of porous carbon materials, the accumulation efficiency and electron transfer ability of AA, DA and UA are improved, and consequently their oxidation signals enhance greatly. Moreover, the interface enhancement effects of porous carbon are also controlled by the particle size of hard template. The constructed porous carbon interface displays strong signal amplification ability and holds great promise in constructing a sensitive platform for the simultaneous determination of AA, DA and UA.

  15. Beyond "born this way?" reconsidering sexual orientation beliefs and attitudes.

    PubMed

    Grzanka, Patrick R; Zeiders, Katharine H; Miles, Joseph R

    2016-01-01

    Previous research on heterosexuals' beliefs about sexual orientation (SO) has been limited in that it has generally examined heterosexuals' beliefs from an essentialist perspective. The recently developed Sexual Orientation Beliefs Scale (SOBS; Arseneau, Grzanka, Miles, & Fassinger, 2013) assesses multifarious "lay beliefs" about SO from essentialist, social constructionist, and constructivist perspectives. This study used the SOBS to explore latent group-based patterns in endorsement of these beliefs in 2 samples of undergraduate students: a mixed-gender sample (n = 379) and an all-women sample (n = 266). While previous research has posited that essentialist beliefs about the innateness of SO predict positive attitudes toward sexual minorities, our research contributes to a growing body of scholarship that suggests that biological essentialism should be considered in the context of other beliefs. Using a person-centered analytic strategy, we found that that college students fell into distinct patterns of SO beliefs that are more different on beliefs about the homogeneity, discreteness, and informativeness of SO categories than on beliefs about the naturalness of SO. Individuals with higher levels of endorsement on all 4 SOBS subscales (a group we named multidimensional essentialism) and those who were highest in discreteness, homogeneity, and informativeness beliefs (i.e., high-DHI) reported higher levels of homonegativity when compared with those who were high only in naturalness beliefs. We discuss the implications of these findings for counseling and psychotherapy about SO, as well educational and social interventions. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  16. Tracking Cognitive Decline in Amnestic Mild Cognitive Impairment and Early-Stage Alzheimer Dementia: Mini-Mental State Examination versus Neuropsychological Battery.

    PubMed

    Kim, Joonho; Na, Han Kyu; Byun, Justin; Shin, Jiwon; Kim, Sungsoo; Lee, Byung Hwa; Na, Duk L

    2017-01-01

    Although the Mini-Mental State Examination (MMSE), Clinical Dementia Rating-Sum of Boxes (CDR-SOB), and neuropsychological batteries are widely used for evaluating cognitive function, it remains elusive which instrument best reflects the longitudinal disease progression in amnestic mild cognitive impairment (aMCI) and probable Alzheimer disease (AD). We investigated whether changes in these three instruments over time correlate with loss of cortical gray matter volume (cGMV). We retrospectively investigated 204 patients (aMCI, n = 114; AD, n = 90) who had undergone MMSE, CDR-SOB, the dementia version of the Seoul Neuropsychological Screening Battery (SNSB-D), and 3-dimensional T1-weighted magnetic resonance images at least twice. We investigated the partial correlation between annual decline in test scores and percent change of cGMV. In aMCI patients, changes in the SNSB-D total score (r = 0.340, p < 0.001) and CDR-SOB (r = 0.222, p = 0.020), but not MMSE, showed a correlation with cGMV loss, with the SNSB-D total score showing the strongest correlation. In AD patients, decline in all three test scores correlated significantly with cGMV loss, with MMSE exhibiting the strongest correlation (r = 0.464, p < 0.001). In aMCI patients, neuropsychological battery, though time-consuming, was the most adequate tool in tracking disease progression. In AD patients, however, MMSE may be the most effective longitudinal monitoring tool when considering cost-effectiveness. © 2017 S. Karger AG, Basel.

  17. Smoking control: challenges and achievements.

    PubMed

    Silva, Luiz Carlos Corrêa da; Araújo, Alberto José de; Queiroz, Ângela Maria Dias de; Sales, Maria da Penha Uchoa; Castellano, Maria Vera Cruz de Oliveira

    2016-01-01

    Smoking is the most preventable and controllable health risk. Therefore, all health care professionals should give their utmost attention to and be more focused on the problem of smoking. Tobacco is a highly profitable product, because of its large-scale production and great number of consumers. Smoking control policies and treatment resources for smoking cessation have advanced in recent years, showing highly satisfactory results, particularly in Brazil. However, there is yet a long way to go before smoking can be considered a controlled disease from a public health standpoint. We can already perceive that the behavior of our society regarding smoking is changing, albeit slowly. Therefore, pulmonologists have a very promising area in which to work with their patients and the general population. We must act with greater impetus in support of health care policies and social living standards that directly contribute to improving health and quality of life. In this respect, pulmonologists can play a greater role as they get more involved in treating smokers, strengthening anti-smoking laws, and demanding health care policies related to lung diseases. RESUMO O tabagismo é o fator de risco mais prevenível e controlável em saúde e, por isso, precisa ter a máxima atenção e ser muito mais enfocado por todos os profissionais da saúde. O tabaco é um produto de alta rentabilidade pela sua grande produção e pelo elevado número de consumidores. As políticas de controle e os recursos terapêuticos para o tabagismo avançaram muito nos últimos anos e têm mostrado resultados altamente satisfatórios, particularmente no Brasil. Entretanto, ainda resta um longo caminho a ser percorrido para que se possa considerar o tabagismo como uma doença controlada sob o ponto de vista da saúde pública. Já se observam modificações do comportamento da sociedade com relação ao tabagismo, mas ainda em escala muito lenta, de modo que os pneumologistas têm nesse setor um campo muito promissor para atuar junto a seus pacientes e a população em geral. É preciso atuar com maior ímpeto em prol das políticas de saúde e das normas de convívio social que contribuem diretamente para melhorar a saúde e a vida. Nesse aspecto, os pneumologistas podem ter um papel de maior destaque na medida em que se envolvam com o tratamento dos fumantes, a aplicação da lei antifumo e as políticas de saúde relacionadas às doenças respiratórias.

  18. Molecular imaging of the dopaminergic system and its association with human cognitive function.

    PubMed

    Cropley, Vanessa L; Fujita, Masahiro; Innis, Robert B; Nathan, Pradeep J

    2006-05-15

    Molecular imaging with positron emission tomography (PET) and single photon emission computed tomography (SPECT) has recently been used to examine dopamine (DA) function and its relationship with cognition in human subjects. This article will review PET and SPECT studies that have explored the relationship between cognitive processes and components of the DA system (pre-, intra-, and postsynaptic) in healthy and patient populations such as Parkinson's disease (PD), schizophrenia, Huntington's disease, and aging. It is demonstrated that DA activity modulates a range of frontal executive-type cognitive processes such as working memory, attentional functioning, and sequential organization, and alterations of DA within the fronto-striato-thalamic circuits might contribute to the cognitive impairments observed in PD, schizophrenia, and normal aging. Although associations between DA and cognitive measures need to be considered within the context of fronto-striato-thalamic circuitry, it is suggested that striatal (especially caudate) DA activity, particularly via D2 receptors, might be important for response inhibition, temporal organization of material, and motor performance, whereas cortical DA transmission via D1 receptors might be important for maintaining and representing on-going behavior.

  19. Amyloid beta precursor protein and ubiquitin epitopes in human and experimental dystrophic axons. Ultrastructural localization.

    PubMed Central

    Bacci, B.; Cochran, E.; Nunzi, M. G.; Izeki, E.; Mizutani, T.; Patton, A.; Hite, S.; Sayre, L. M.; Autilio-Gambetti, L.; Gambetti, P.

    1994-01-01

    Dystrophic axons (DA) represent a major pathological feature of several neurodegenerative disorders, including infantile neuroaxonal dystrophy (INAD) and Alzheimer disease. We have previously presented evidence that amyloid beta precursor protein (BPP) and ubiquitin (Ub) are present in DA of different origin. We have now characterized the immunoreactivity of DA experimentally induced in rat by the administration of parabromophenylacetylurea (BPAU) and examined the subcellular localization of Ub and BPP in BPAU-induced DA and in DA present in subjects affected by INAD. BPAU-induced DA strongly immunoreacted with antisera to Ub and to COOH- and NH2-terminal regions of BPP. Immunoblots of DA-enriched brain regions were consistent with an increase in the amount of Ub and BPP in DA. Moreover, BPAU-induced DA immunoreacted with antibodies to PGP 9.5, a neuronal-specific Ub COOH-terminal hydrolase, and to the inducible heat shock protein 70. Antigenic characterization also indicated that the tubulovesicular membranes within DA derived largely from the smooth endoplasmic reticulum rather than from the Golgi system or the synaptic vesicles. Subcellular immunolocalization of Ub and BPP in both INAD- and BPAU-induced DA revealed that Ub and BPP colocalize in granulovesicular material in both conditions. In INAD DA intense Ub immunoreactivity was also detected in nonmembranous electron dense structures that were present only in these DA, probably because of the chronic course of INAD. Although BPP immunostaining may be related to accumulation of BPP-containing membranes in DA, Ub immunostaining is likely to result from activation of the Ub system by the neuron in the attempt to remove excessive and possibly abnormal proteins. A similar pathogenesis can be postulated for DA of Alzheimer disease. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7512790

  20. The DaNa2.0 Knowledge Base Nanomaterials—An Important Measure Accompanying Nanomaterials Development

    PubMed Central

    Bohmer, Nils; Marquardt, Clarissa; Nau, Katja; Steinbach, Christoph

    2018-01-01

    Nanotechnology is closely related to the tailored manufacturing of nanomaterials for a huge variety of applications. However, such applications with newly developed materials are also a reason for concern. The DaNa2.0 project provides information and support for these issues on the web in condensed and easy-to-understand wording. Thus, a key challenge in the field of advanced materials safety research is access to correct and reliable studies and validated results. For nanomaterials, there is currently a continuously increasing amount of publications on toxicological issues, but criteria to evaluate the quality of these studies are necessary to use them e.g., for regulatory purposes. DaNa2.0 discusses scientific results regarding 26 nanomaterials based on actual literature that has been selected after careful evaluation following a literature criteria checklist. This checklist is publicly available, along with a selection of standardized operating protocols (SOPs) established by different projects. The spectrum of information is rounded off by further articles concerning basics or crosscutting topics in nanosafety research. This article is intended to give an overview on DaNa2.0 activities to support reliable toxicity testing and science communication alike. PMID:29596351

  1. Effects of emissions from sugar cane burning on the trachea and lungs of Wistar rats.

    PubMed

    Matos, Verena Sampaio Barbosa; Gomes, Felipe da Silva; Oliveira, Tarcio Macena; Schulz, Renata da Silva; Ribeiro, Lídia Cristina Villela; Gonzales, Astria Dias Ferrão; Lima, Januário Mourão; Guerreiro, Marcos Lázaro da Silva

    2017-01-01

    To evaluate the effects of exposure to emissions from sugar cane burning on inflammatory mechanisms in tissues of the trachea and lung parenchyma in Wistar rats after different periods of exposure. This was an experimental open randomized study. The animals were divided into four groups: a control group (CG) underwent standard laboratory conditions, and three experimental groups were exposed to emissions from sugar cane burning over different periods of time, in days-1 (EG1), 7 (EG7), and 21 (EG21). After euthanasia with 200 mg/kg of ketamine/xylazine, fragments of trachea and lung were collected and fixed in 10% formalin. Histological analyses were performed with H&E and picrosirius red staining. No inflammatory infiltrates were found in the tissues of CG rats. The histological examination of tissues of the trachea and lung parenchyma revealed that the inflammatory process was significantly more intense in EG7 than in the CG (p < 0.05 and p < 0.01, respectively). In comparison with the CG and EG1, angiogenesis in the lung parenchyma and collagen deposition in tracheal tissues were significantly greater only in EG21 (p < 0.001 and p < 0.01, respectively). In this sample, emissions from sugar cane burning induced acute focal and diffuse inflammation in the lamina propria of tracheal tissues, with no loss of ciliated epithelial tissue. In the lung parenchyma of the animals in the experimental groups, there was interstitial and alveolar edema, together with polymorphonuclear cell infiltrates. Avaliar os efeitos da exposição à fumaça da queima da cana-de-açúcar sobre mecanismos inflamatórios em tecidos de traqueia e de parênquima pulmonar de ratos Wistar após diferentes períodos de exposição. Estudo experimental, randomizado, não cego. Os animais foram divididos em quatro grupos: controle (GC), sob condições padrão de laboratório e os demais expostos à fumaça da queima da cana-de-açúcar por diferentes períodos: em 1 (GE1), 7 (GE7) e 21 (GE21) dias. Após a eutanásia com 200 mg/kg de ketamina/xilazina, foram coletados fragmentos de traqueia e pulmão e fixadas em formol 10%. Análises histológicas foram realizadas com coloração com H&E e picrosírius. Não houve infiltrado inflamatório nos tecidos no GC. O processo inflamatório na análise histológica de tecidos de traqueia e de parênquima pulmonar foi significativamente mais intenso no GE7 quando comparado ao GC (p < 0,05 e p < 0,01, respectivamente). Em comparação com os grupos GC e GE1, apenas no GE21 foi observada angiogênese significativa no parênquima pulmonar e aumento significativo de depósitos de colágeno em tecido de traqueia (p < 0,001 e p < 0,01, respectivamente). Nesta amostra, a fumaça da queima de cana-de-açúcar induziu processo inflamatório focal, difuso e agudo em tecidos de traqueia na lâmina própria, sem perda do tecido epitelial ciliado. Houve presença de edemas intersticiais e alveolares e infiltrados de células polimorfonucleares no parênquima pulmonar nos animais dos grupos experimentais.

  2. Shortness of breath: Patient history not always indicative of the cause.

    PubMed

    Brar, Tony S; Akhavan, Neeka

    2016-01-01

    This is a 78 year old male with a past medical history of coronary artery disease (CAD), chronic obstructive pulmonary disease (COPD), hypertension (HTN), and gastroesophageal reflux disorder (GERD) who presented to the emergency room with worsening shortness of breath (SOB) and low-grade fevers for one week prior to admission. He was originally diagnosed with healthcare associated pneumonia (HCAP) and an acute on chronic COPD exacerbation and treated with prednisone, inhalers, ipratropium/albuterol, and broad-spectrum antibiotics. His symptoms were slow to respond to therapy and he continued to have end-expiratory wheezes with persistent SOB. A CT of his chest was ordered to rule out a possible pulmonary embolus (PE) and instead showed an obstructing mass in the bronchus. Pulmonology was consulted and performed a bronchoscopy, which revealed a foreign body (bean) causing the obstruction, which was removed, and the patient's symptoms improved shortly thereafter.

  3. Effectivity of immunostimulant from Zoothamnium penaei protein membrane for decreasing the mortality rate of white shrimp (Litopenaeus vannamei) in traditional plus pond

    NASA Astrophysics Data System (ADS)

    Mahasri, G.; Kusdarwati, R.; Kismiyati; Rozi; Gustrifandi, H.

    2018-04-01

    The purpose of this research was to analys immunogenic membrane protein as immunostimulant development material to control the mortality of white shrimp in traditional plus pond. This research was designed to use explorative experiment and experimental laboratory methods which used completed random sampling design. Collected data was analyzed with analysis of variance for examination of survival rate (SR), total haemocyte count (THC) and differensial haemocyte Count (DHC). The research divided into 2 part of riset: (1) Identification, cultivation Zoothamnium penaei, analysed of membrane protein by SDS-PAGE, (2) Field test protein membran on Survival Rate level, immune response (THC and/or DHC level) and infestation of Zoothamnium penaei in traditional plus pond. The result showed that there were seven bands membrane protein of Zoothamnium penaei with molecular weight 38 kDa, 48 kDa, 67 kDa, 71 kDa, 77 kDa, 98 kDa dan 104 kDa by using SDS-PAGE. Immunogenicity tested decrease by using ELISA and western blotting there are only found three bands with molecular weight 38 kDa, 48 kDa dan 67 kDa. The membrane protein could increase the immun respons and decrease the mortality, by subsequenly, it could increase the survival rate from 17% until 68% and pressured the parasite infestation of white shrimp.

  4. 32 CFR 643.22 - Policy-Public safety: Requirement for early identification of lands containing dangerous materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Policy-Public safety: Requirement for early identification of lands containing dangerous materials. 643.22 Section 643.22 National Defense Department of...—Public safety: Requirement for early identification of lands containing dangerous materials. (a) DA will...

  5. 32 CFR 643.22 - Policy-Public safety: Requirement for early identification of lands containing dangerous materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Policy-Public safety: Requirement for early identification of lands containing dangerous materials. 643.22 Section 643.22 National Defense Department of...—Public safety: Requirement for early identification of lands containing dangerous materials. (a) DA will...

  6. Significance of ITER IWS Material Selection and Qualification

    NASA Astrophysics Data System (ADS)

    Mehta, Bhoomi K.; Raval, Jigar; Maheshwari, Abha; Laad, Rahul; Singh, Gurlovleen; Pathak, Haresh

    2017-04-01

    In-Wall Shielding (IWS) is one of the important components of ITER Vacuum Vessel (VV) which fills the space between double walls of VV with cooling water. Procurement Arrangement (PA) for IWS has been signed with Indian Domestic Agency (INDA). Procurement of IWS materials, fabrication of IWS blocks and its delivery to respective Domestic Agency (DA) and ITER Organization (IO) are the main scope of this PA. Hence, INDIA is the only country which is contributing to VV IWS among all seven ITER partners. The main functions of the IWS are to provide Neutron Shielding with blanket, VV shells and water during plasma operations and to reduce ripple of the Toroidal Magnetic Field. To meet these functional requirements IWS blocks are made up of special materials (Borated Steels SS304 B4 & SS304 B7, Ferritic Steels SS 430, Austenitic Steel SS 316 L (N)-IG, XM-19 and Inconel-625) which are qualified, reliable and traceable for the design assessment. The choice of these materials has a significant influence on performance, maintainability, licensing, detailed design parameters and waste disposal. The main reasons for the materials selected for IWS are its high mechanical strength at operating temperatures, water chemistry properties, excellent fabrication characteristics and low cost relative to other similar materials. All the materials are qualified with respect to their respective codes (ASTM/EN standards with additional requirements as described in RCC-MR code 2007) and ITER requirements. Agreed Notified Body (ANB) has control conformity of materials certificates with approved material specification and traceability procedure for Safety Important Component (SIC). The procurement strategy for all the IWS materials has been developed in close collaboration with IO, ANB and Industries as per Product Procurement Specification (PPS). The R&D for sample, bulk material production, testing, inspection and handling as required are carried out by IN DA and IO. At present almost all IWS materials (∼2500 Tons) has been procured by IN DA with spares to manufacture ∼9000 IWS blocks. This paper summarizes IWS material selection, qualification and procurement processes in detail.

  7. Structure and function of natural sulphide-oxidizing microbial mats under dynamic input of light and chemical energy

    PubMed Central

    Klatt, Judith M; Meyer, Steffi; Häusler, Stefan; Macalady, Jennifer L; de Beer, Dirk; Polerecky, Lubos

    2016-01-01

    We studied the interaction between phototrophic and chemolithoautotrophic sulphide-oxidizing microorganisms in natural microbial mats forming in sulphidic streams. The structure of these mats varied between two end-members: one characterized by a layer dominated by large sulphur-oxidizing bacteria (SOB; mostly Beggiatoa-like) on top of a cyanobacterial layer (B/C mats) and the other with an inverted structure (C/B mats). C/B mats formed where the availability of oxygen from the water column was limited (<5 μm). Aerobic chemolithotrophic activity of the SOB depended entirely on oxygen produced locally by cyanobacteria during high light conditions. In contrast, B/C mats formed at locations where oxygen in the water column was comparatively abundant (>45 μM) and continuously present. Here SOB were independent of the photosynthetic activity of cyanobacteria and outcompeted the cyanobacteria in the uppermost layer of the mat where energy sources for both functional groups were concentrated. Outcompetition of photosynthetic microbes in the presence of light was facilitated by the decoupling of aerobic chemolithotrophy and oxygenic phototrophy. Remarkably, the B/C mats conserved much less energy than the C/B mats, although similar amounts of light and chemical energy were available. Thus ecosystems do not necessarily develop towards optimal energy usage. Our data suggest that, when two independent sources of energy are available, the structure and activity of microbial communities is primarily determined by the continuous rather than the intermittent energy source, even if the time-integrated energy flux of the intermittent energy source is greater. PMID:26405833

  8. Bioreactor performance and functional gene analysis of microbial community in a limited-oxygen fed bioreactor for co-reduction of sulfate and nitrate with high organic input.

    PubMed

    Xu, Xi-jun; Chen, Chuan; Wang, Ai-jie; Yu, Hao; Zhou, Xu; Guo, Hong-liang; Yuan, Ye; Lee, Duu-jong; Zhou, Jizhong; Ren, Nan-qi

    2014-08-15

    Limited-oxygen mediated synergistic relationships between sulfate-reducing bacteria (SRB), nitrate-reducing bacteria (NRB) and sulfide-oxidizing bacteria (SOB, including nitrate-reducing, sulfide-oxidizing bacteria NR-SOB) were predicted to simultaneously remove contaminants of nitrate, sulfate and high COD, and eliminate sulfide generation. A lab-scale experiment was conducted to examine the impact of limited oxygen on these oxy-anions degradation, sulfide oxidation and associated microbial functional responses. In all scenarios tested, the reduction of both nitrate and sulfate was almost complete. When limited-oxygen was fed into bioreactors, S(0) formation was significantly improved up to ∼ 70%. GeoChip 4.0, a functional gene microarray, was used to determine the microbial gene diversity and functional potential for nitrate and sulfate reduction, and sulfide oxidation. The diversity of the microbial community in bioreactors was increased with the feeding of limited oxygen. Whereas the intensities of the functional genes involved in sulfate reduction did not show a significant difference, the abundance of the detected denitrification genes decreased in limited oxygen samples. More importantly, sulfide-oxidizing bacteria may alter their populations/genes in response to limited oxygen potentially to function more effectively in sulfide oxidation, especially to elemental sulfur. The genes fccA/fccB from nitrate-reducing, sulfide-oxidizing bacteria (NR-SOB), such as Paracoccus denitrificans, Thiobacillus denitrificans, Beggiatoa sp., Thiomicrospira sp., and Thioalkalivibrio sp., were more abundant under limited-oxygen condition. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Clinical-Functional Vulnerability Index-20 (IVCF-20): rapid recognition of frail older adults.

    PubMed

    Moraes, Edgar Nunes de; Carmo, Juliana Alves do; Moraes, Flávia Lanna de; Azevedo, Raquel Souza; Machado, Carla Jorge; Montilla, Dalia Elena Romero

    2016-12-22

    To evaluate the adequacy of the Clinical-Functional Vulnerability Index-20, a rapid triage instrument to test vulnerability in Brazilian older adults, for the use in primary health care. The study included convenience sample of 397 patients aged older than or equal to 60 years attended at Centro de Referência para o Idoso (Reference Center for Older Adults) and of 52 older adults the same age attended at the community. The results of the questionnaire, consisting of 20 questions, were compared with those of the Comprehensive Geriatric Assessment, considered a reference for identifying frail older adults. Spearman's correlation was evaluated in the Clinical-Functional Vulnerability Index-20 with the Comprehensive Geriatric Assessment; the validity was verified by the area under the ROC curve; reliability was estimated by the percentage of agreement among evaluators and by the kappa coefficient, both with quadratic weighted. The cut-off point was obtained based on the higher accuracy criterion. Cronbach's alpha, a measure of internal consistency, was estimated. The Spearman's correlation coefficient was high and positive for both groups (0.792 for older adults attended at the Reference Center and 0.305 for older adults from the community [p < 0.001]). The area under the ROC curve for older adults attended at the Reference Center was substantial (0.903). The cut-off point obtained was six, and older adults with scores in Clinical-Functional Vulnerability Index-20 above that value had strong possibility of being frail. For older adults from the community, the quadratic weighted agreement among evaluators was 99.5%, and the global quadratic weighted kappa coefficient was 0.94. Cronbach's alpha was high for older adults attended at the Reference Center (0.861) and those attended at the community (0.740). The Clinical-Functional Vulnerability Index-20 questionnaire, in the sample examined, turned out to be positively correlated with the Comprehensive Geriatric Assessment, in addition to the results indicating a high degree of validity and reliability. Thus, the Clinical-Functional Vulnerability Index-20 proves to be viable as a triage instrument in the primary health care that identifies frail older adults (older adults at risk of weakening and frail older adults). Avaliar a adequação do Índice de Vulnerabilidade Clínico-Funcional-20 , instrumento de triagem rápida de vulnerabilidade em idosos brasileiros, para utilização pela atenção básica. O estudo incluiu amostra de conveniência de 397 pacientes com idade maior ou igual a 60 anos atendidos em um Centro de Referência para o Idoso e de 52 idosos da mesma idade atendidos na comunidade. Os resultados do questionário, constituído por 20 perguntas, foram comparados com aqueles da Avaliação Geriátrica Ampla, considerada referência para identificação do idoso frágil. Foi avaliada a correlação de Spearman do Índice de Vulnerabilidade Clínico-Funcional-20 com a Avaliação Geriátrica Ampla; a validade foi verificada pela área sob a curva ROC; a confiabilidade foi estimada pelo percentual de concordância entre avaliadores e coeficiente kappa, ambos com ponderação quadrática. Obteve-se ponto de corte com base no critério de maior acurácia. O alfa de Cronbach, medida de consistência interna, foi calculado. O coeficiente de correlação de Spearman foi elevado e positivo em ambos os grupos (0,792 para idosos atendidos no Centro de Referência para o Idoso e 0,305 para idosos da comunidade [p < 0,001]). A área sob a curva ROC para idosos atendidos no Centro de Referência para o Idoso foi substancial (0,903). O ponto de corte obtido foi seis e idosos com pontuação no Índice de Vulnerabilidade Clínico-Funcional-20 acima desse valor tinham forte possibilidade de serem frágeis. Para idosos da comunidade, a concordância ponderada quadrática entre avaliadores foi 99,5% e o coeficiente kappa ponderado quadrático global, 0,94. O alfa de Cronbach foi elevado para idosos atendidos no Centro de Referência para o Idoso (0,861) e da comunidade (0,740). O questionário do Índice de Vulnerabilidade Clínico-Funcional-20, na amostra analisada, mostrou ser positivamente correlacionado com a Avaliação Geriátrica Ampla, além de os resultados indicarem alto grau de validade e confiabilidade. Assim, o Índice de Vulnerabilidade Clínico-Funcional-20 se mostra viável como instrumento de rastreio na atenção básica que identifica o idoso com fragilidade (idoso em risco de fragilização e idoso frágil).

  10. Design of New Bridge-Ring Energetic Compounds Obtained by Diels-Alder Reactions of Tetranitroethylene Dienophile.

    PubMed

    He, Piao; Mei, Hao-Zheng; Wu, Le; Yang, Jun-Qing; Zhang, Jian-Guo; Cohen, Adva; Gozin, Michael

    2018-03-29

    The density functional theory method was employed to calculate three-dimensional structures for a series of novel explosophores. The design of new molecules (DA1-DA12) was based on the bridge-ring structures that could be formed via Diels-Alder (DA) reaction of selected nitrogen-rich dienes and tetranitroethylene dienophile. The feasibility of the proposed DA reactions was predicted on the basis of the molecular orbital theory. The strong interactions between the HOMO of dienes, with electron-donating groups (Diene2, Diene6, and Diene8), and the LUMO of tetranitroethylene dienophile suggested thermodynamically favorable formation of the desired DA reaction products. In addition to molecular structures of the explored DA compounds, their physicochemical and energetic properties were also calculated in detail. Due to compact bridge-ring structures, new energetic molecules have highly positive heats of formation (up to 1124.90 kJ·mol -1 ) and high densities (up to 2.04 g·cm -3 ). Also, as a result of all-right ratios of nitrogen and oxygen, most of the new compounds possess high detonation velocities (8.28-10.02 km·s -1 ) and high detonation pressures (30.87-47.83 GPa). Energetic compounds DA1, DA4, and DA12 exhibit a superior detonation performance over widely used HMX explosive, and DA5, DA7, and DA10 could be comparable to the state-of-the-art CL-20 and ONC explosives. Our proposed designs and synthetic methodology should provide a platform for the development of novel energetic materials with superior performance.

  11. A Photoelastic Study of Load Distributions and Stresses in Multi-Groove Connections of the Same Material under Tension.

    DTIC Science & Technology

    1982-05-01

    CALIBER WEAPON SYSTEMS LABORATORY BENleT WEAPONS LABORATORY WATERVLIET, N. Y. 12189 ANCMS No. 61110191A0011 DA Project No. 1L161101AS& PRON No...Benet Weapons Laboratory, DRDAR-LCB-TL DA Project No. lL16110IA9A Watervliet, NY 12189 PRON No. 1A2231491AIA I. CONTROLLING OFFICE NAME AND ADDRESS 12

  12. Combined Application of UHPLC-QTOF/MS, HPLC-ELSD and 1 H-NMR Spectroscopy for Quality Assessment of DA-9801, A Standardised Dioscorea Extract.

    PubMed

    Kang, Kyo Bin; Ryu, Jayoung; Cho, Youngwoong; Choi, Sang-Zin; Son, Miwon; Sung, Sang Hyun

    2017-05-01

    DA-9801, a standardised 50% aqueous ethanolic extract of a mixture of Dioscorea japonica and D. nipponica, is a botanical drug candidate for the treatment of diabetic neuropathy, which finished its US phase II clinical trials recently. An advanced quality control method is needed for further development of DA-9801, considering its high contents of both primary and secondary metabolites. Development of a quality assessment strategy for DA-9801, based on the combination of UHPLC-QTOF/MS, HPLC-ELSD, and 1 H-NMR spectroscopy. The method was developed and tested with 15 batch products of DA-9801. The steroidal saponins of DA-9801 were tentatively identified by UHPLC-QTOF/MS and were quantified with the validated HPLC-ELSD method. Primary metabolites of DA-9801 were identified and profiled using 1 H-NMR spectrometry. The batch-to-batch equivalence of DA-9801 was tested with the 1 H-NMR spectra using spectral binning, correlation analysis, and principal component analysis. Six major saponins of DA-9801 were tentatively identified by UHPLC-QTOF/MS. Among them, protodioscin and dioscin were quantified by the validated HPLC-ELSD method. Twenty-six metabolites were identified in 1 H-NMR spectra. The similarity between DA-9801 batches could be evaluated with the NMR spectra of DA-9801. The 1 H-NMR method also revealed that two Dioscorea species contributed distinct amino acids to the contents of DA-9801. This study validates the effectiveness of UHPLC-QTOF/MS, HPLC-ELSD, and 1 H NMR-combined method for quality control of DA-9801 and its crude materials. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Fluorinated arene, imide and unsaturated pyrrolidinone based donor acceptor conjugated polymers: Synthesis, structure-property and device studies

    NASA Astrophysics Data System (ADS)

    Liyanage, Arawwawala Don Thilanga

    After the discovery of doped polyacetylene, organic semiconductor materials are widely studied as high impending active components in consumer electronics. They have received substantial consideration due to their potential for structural tailoring, low cost, large area and mechanically flexible alternatives to common inorganic semiconductors. To acquire maximum use of these materials, it is essential to get a strong idea about their chemical and physical nature. Material chemist has an enormous role to play in this novel area, including development of efficient synthetic methodologies and control the molecular self-assembly and (opto)-electronic properties. The body of this thesis mainly focuses on the substituent effects: how different substituents affect the (opto)-electronic properties of the donor-acceptor (D-A) conjugated polymers. The main priority goes to understand, how different alkyl substituent effect to the polymer solubility, crystallinity, thermal properties (e.g.: glass transition temperature) and morphological order. Three classes of D-A systems were extensively studied in this work. The second chapter mainly focuses on the synthesis and structure-property study of fluorinated arene (TFB) base polymers. Here we used commercially available 1,4-dibromo-2,3,5,6-tetrafluorobenzene (TFB) as the acceptor material and prepare several polymers using 3,3'-dialkyl(3,3'-R2T2) or 3,3'-dialkoxy bithiophene (3,3'-RO2T2) units as electron donors. A detail study was done using 3,3'-bithiophene donor units incorporating branched alkoxy-functionalities by systematic variation of branching position and chain length. The study allowed disentangling the branching effects on (i) aggregation tendency, intermolecular arrangement, (iii) solid state optical energy gaps, and (iv) electronic properties in an overall consistent picture, which might guide future polymer synthesis towards optimized materials for opto-electronic applications. The third chapter mainly focused on the structure-property study of imide functionalized D-A polymers. Here we used thiophene-imide (TPD) as the acceptor moiety and prepare several D-A polymers by varying the donor units. When selecting the donor units, more priority goes to the fused ring systems. One main reason to use imide functionality is due to the, open position of the imide nitrogen, which provides an attaching position to alkyl substituent. Through this we can easily manipulate solubility and solid state packing arrangement. Also these imide acceptors have low-lying LUMOs due to their electron deficient nature and this will allow tuning the optical energy gap by careful choice of donor materials with different electron donating ability. The fourth chapter mainly contribute to the synthesis and structure property study of a completely novel electron acceptor moiety consist of a unsaturated pyrrolidinone unit known as Pechmann dye (PD) core. Pechmann dyes are closely related to the Indigo family. This can refer as 3-butenolide dimer connected via an alkene bridge, containing a benzene ring at the 5 and 5' positions of the lactone rings. We have prepared several D-A polymers using this PD system with benzodithiophene (BDT) as the donor unit. Different to common D-A polymers the HOMO and LUMO of the PD acceptor moiety are energetically located within the gap of the BDT, so that the electronic and optical properties (HOMO-LUMO transition) are dictated by the PD properties. The promising electronic properties, band gaps, high absorption coefficients and broad absorption suggest this new D-A polymers as an interesting donor material for organic solar cell (OSC) applications. KEY WORDS: Organic semiconductor materials, Self assembly, (opto)-electronic properties, Donor-Acceptor conjugated polymers, Fluorinated arene, 3,3'-bithiophene donors, Thiophene-imide (TPD), Pechmann dye, benzodithiophene, organic solar cell.

  14. Experimental study and neural network modeling of sugarcane bagasse pretreatment with H2SO4 and O3 for cellulosic material conversion to sugar.

    PubMed

    Gitifar, Vahid; Eslamloueyan, Reza; Sarshar, Mohammad

    2013-11-01

    In this study, pretreatment of sugarcane bagasse and subsequent enzymatic hydrolysis is investigated using two categories of pretreatment methods: dilute acid (DA) pretreatment and combined DA-ozonolysis (DAO) method. Both methods are accomplished at different solid ratios, sulfuric acid concentrations, autoclave residence times, bagasse moisture content, and ozonolysis time. The results show that the DAO pretreatment can significantly increase the production of glucose compared to DA method. Applying k-fold cross validation method, two optimal artificial neural networks (ANNs) are trained for estimations of glucose concentrations for DA and DAO pretreatment methods. Comparing the modeling results with experimental data indicates that the proposed ANNs have good estimation abilities. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Onsite Gaseous Centrifuge Enrichment Plant UF6 Cylinder Destructive Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anheier, Norman C.; Cannon, Bret D.; Qiao, Hong

    2012-07-17

    The IAEA safeguards approach for gaseous centrifuge enrichment plants (GCEPs) includes measurements of gross, partial, and bias defects in a statistical sampling plan. These safeguard methods consist principally of mass and enrichment nondestructive assay (NDA) verification. Destructive assay (DA) samples are collected from a limited number of cylinders for high precision offsite mass spectrometer analysis. DA is typically used to quantify bias defects in the GCEP material balance. Under current safeguards measures, the operator collects a DA sample from a sample tap following homogenization. The sample is collected in a small UF6 sample bottle, then sealed and shipped under IAEAmore » chain of custody to an offsite analytical laboratory. Current practice is expensive and resource intensive. We propose a new and novel approach for performing onsite gaseous UF6 DA analysis that provides rapid and accurate assessment of enrichment bias defects. DA samples are collected using a custom sampling device attached to a conventional sample tap. A few micrograms of gaseous UF6 is chemically adsorbed onto a sampling coupon in a matter of minutes. The collected DA sample is then analyzed onsite using Laser Ablation Absorption Ratio Spectrometry-Destructive Assay (LAARS-DA). DA results are determined in a matter of minutes at sufficient accuracy to support reliable bias defect conclusions, while greatly reducing DA sample volume, analysis time, and cost.« less

  16. Preparation of Cu₂O-Reduced Graphene Nanocomposite Modified Electrodes towards Ultrasensitive Dopamine Detection.

    PubMed

    He, Quanguo; Liu, Jun; Liu, Xiaopeng; Li, Guangli; Deng, Peihong; Liang, Jing

    2018-01-12

    Cu₂O-reduced graphene oxide nanocomposite (Cu₂O-RGO) was used to modify glassy carbon electrodes (GCE), and applied for the determination of dopamine (DA). The microstructure of Cu₂O-RGO nanocomposite material was characterized by scanning electron microscope. Then the electrochemical reduction condition for preparing Cu₂O-RGO/GCE and experimental conditions for determining DA were further optimized. The electrochemical behaviors of DA on the bare electrode, RGO- and Cu₂O-RGO-modified electrodes were also investigated using cyclic voltammetry in phosphate-buffered saline solution (PBS, pH 3.5). The results show that the oxidation peaks of ascorbic acid (AA), dopamine (DA), and uric acid (UA) could be well separated and the peak-to-peak separations are 204 mV (AA-DA) and 144 mV (DA-UA), respectively. Moreover, the linear response ranges for the determination of 1 × 10 -8 mol/L~1 × 10 -6 mol/L and 1 × 10 -6 mol/L~8 × 10 -5 mol/L with the detection limit 6.0 × 10 -9 mol/L (S/N = 3). The proposed Cu₂O-RGO/GCE was further applied to the determination of DA in dopamine hydrochloride injections with satisfactory results.

  17. A clinical evaluation denture adhesives used by patients with xerostomia.

    PubMed

    Bogucki, Zdzislaw A; Napadlek, Piotr; Dabrowa, Tomasz

    2015-02-01

    The purpose of study was to analyze the participants' opinions concerning the effectiveness of 6 denture adhesives (DA). The study group included 60 participants. Criteria for selecting the patients were as follows: reduced retention and stabilization of maxillary complete dentures and xerostomia. These features were evaluated on basis of clinical examination and standard sialometry tests (u-SFR). Retention of maxillary dentures was scored by modified Kapur index before application of DA. All participants were divided randomly into 6 groups regarding the use of the 6 DA during a 6-month period. After this time, participants completed an HRQL questionnaire. DA noticeably improved retention and stabilization of maxillary complete dentures. DA in the glue form had the best retention effectiveness in participants with xerostomia. These materials are difficult to clean from the denture base. The data are presented in tables and figures. The results of the study collected positive influence of adhesives on retention of dentures in xerostomia patients. The cleaning dentures and denture bearing tissues was difficult. DA help in the use of prostheses, but it is also necessary for the treatment of the causes and symptoms of xerostomia.

  18. Tailoring Oxygen Sensitivity with Halide Substitution in Difluoroboron Dibenzoylmethane Polylactide Materials

    PubMed Central

    DeRosa, Christopher A.; Kerr, Caroline; Fan, Ziyi; Kolpaczynska, Milena; Mathew, Alexander S.; Evans, Ruffin E.; Zhang, Guoqing; Fraser, Cassandra L.

    2015-01-01

    The dual-emissive properties of solid-state difluoroboron β-diketonate-poly(lactic acid) (BF2bdkPLA) materials have been utilized for biological oxygen sensing. In this work, BF2dbm(X)PLA materials were synthesized, where X = H, F, Cl, Br, and I. The effects of changing the halide substituent and PLA polymer chain length on the optical properties in dilute CH2Cl2 solutions and solid-state polymer films were studied. These luminescent materials show fluorescence, phosphorescence, and lifetime tunability on the basis of molecular weight, as well as lifetime modulation via the halide substituent. Short BF2dbm(Br)PLA (6.0 kDa) and both short and long BF2dbm(I)PLA polymers (6.0 or 20.3 kDa) have fluorescence and intense phosphorescence ideal for ratiometric oxygen sensing. The lighter halide-dye polymers with hydrogen, fluorine, and chlorine substitution have longer phosphorescence lifetimes and can be utilized as ultrasensitive oxygen sensors. Photostability was also analyzed for the polymer films. PMID:26480236

  19. Interfacial Charge Transfer States in Condensed Phase Systems

    NASA Astrophysics Data System (ADS)

    Vandewal, Koen

    2016-05-01

    Intermolecular charge transfer (CT) states at the interface between electron-donating (D) and electron-accepting (A) materials in organic thin films are characterized by absorption and emission bands within the optical gap of the interfacing materials. CT states efficiently generate charge carriers for some D-A combinations, and others show high fluorescence quantum efficiencies. These properties are exploited in organic solar cells, photodetectors, and light-emitting diodes. This review summarizes experimental and theoretical work on the electronic structure and interfacial energy landscape at condensed matter D-A interfaces. Recent findings on photogeneration and recombination of free charge carriers via CT states are discussed, and relations between CT state properties and optoelectronic device parameters are clarified.

  20. THERMAL FATIGUE OF INCONEL ALLOY DA718

    DTIC Science & Technology

    2016-10-27

    this material meets the required improvement and offers a low cost alternative to powder metallurgy Rene’95. However, its thermal fatigue resistance ...remains to be fully clarified. Its nominal chemical composition is shown in Table B-1. In the fully heat treated condition, DA718 consists of a γ...chromel-alumel thermocouple , spot-welded to the mid-length of the specimen. The thermal strain, induced by the expansion and contraction of the

  1. Regolith grain size and cohesive strength of near-Earth Asteroid (29075) 1950 DA

    NASA Astrophysics Data System (ADS)

    Gundlach, B.; Blum, J.

    2015-09-01

    Due to its fast rotation period of 2.12 h, about half of the surface of near-Earth Asteroid (29075) 1950 DA experiences negative (i.e., outward directed) acceleration levels (Rozitis, B., Maclennan, E., Emery, J.P. [2014]. Nature 512, 174-176). Thus, cohesion of the surface material is mandatory to prevent rotational breakup of the asteroid. Rozitis et al. (Rozitis, B., Maclennan, E., Emery, J.P. [2014]. Nature 512, 174-176) concluded that a grain size of ∼6 cm or lower is needed to explain the required cohesive strength of 64-20+12Pa . Here, we present another approach to determine the grain size of near-Earth Asteroid (29075) 1950 DA by using the thermal inertia value from Rozitis et al. (Rozitis, B., Maclennan, E., Emery, J.P. [2014]. Nature 512, 174-176) and a model of the heat conductivity of the surface regolith (Gundlach, B., Blum, J. [2013]. Icarus 223, 479-492). This method yields a mean particle radius ranging from 32 μm to 117 μm. The derived grain sizes are then used to infer the cohesive strength of the surface material of Asteroid (29075) 1950 DA (ranging from 24 Pa to 88 Pa), by using laboratory measurements of the tensile strength of powders.

  2. Interfering with memory for faces: The cost of doing two things at once.

    PubMed

    Wammes, Jeffrey D; Fernandes, Myra A

    2016-01-01

    We inferred the processes critical for episodic retrieval of faces by measuring susceptibility to memory interference from different distracting tasks. Experiment 1 examined recognition of studied faces under full attention (FA) or each of two divided attention (DA) conditions requiring concurrent decisions to auditorily presented letters. Memory was disrupted in both DA relative to FA conditions, a result contrary to a material-specific account of interference effects. Experiment 2 investigated whether the magnitude of interference depended on competition between concurrent tasks for common processing resources. Studied faces were presented either upright (configurally processed) or inverted (featurally processed). Recognition was completed under FA, or DA with one of two face-based distracting tasks requiring either featural or configural processing. We found an interaction: memory for upright faces was lower under DA when the distracting task required configural than featural processing, while the reverse was true for memory of inverted faces. Across experiments, the magnitude of memory interference was similar (a 19% or 20% decline from FA) regardless of whether the materials in the distracting task overlapped with the to-be-remembered information. Importantly, interference was significantly larger (42%) when the processing demands of the distracting and target retrieval task overlapped, suggesting a processing-specific account of memory interference.

  3. Improved detection of highly energetic materials traces on surfaces by standoff laser-induced thermal emission incorporating neural networks

    NASA Astrophysics Data System (ADS)

    Figueroa-Navedo, Amanda; Galán-Freyle, Nataly Y.; Pacheco-Londoño, Leonardo C.; Hernández-Rivera, Samuel P.

    2013-05-01

    Terrorists conceal highly energetic materials (HEM) as Improvised Explosive Devices (IED) in various types of materials such as PVC, wood, Teflon, aluminum, acrylic, carton and rubber to disguise them from detection equipment used by military and security agency personnel. Infrared emissions (IREs) of substrates, with and without HEM, were measured to generate models for detection and discrimination. Multivariable analysis techniques such as principal component analysis (PCA), soft independent modeling by class analogy (SIMCA), partial least squares-discriminant analysis (PLS-DA), support vector machine (SVM) and neural networks (NN) were employed to generate models, in which the emission of IR light from heated samples was stimulated using a CO2 laser giving rise to laser induced thermal emission (LITE) of HEMs. Traces of a specific target threat chemical explosive: PETN in surface concentrations of 10 to 300 ug/cm2 were studied on the surfaces mentioned. Custom built experimental setup used a CO2 laser as a heating source positioned with a telescope, where a minimal loss in reflective optics was reported, for the Mid-IR at a distance of 4 m and 32 scans at 10 s. SVM-DA resulted in the best statistical technique for a discrimination performance of 97%. PLS-DA accurately predicted over 94% and NN 88%.

  4. Professionals and interfamily violence against children and adolescents: in between legal and conceptual precepts.

    PubMed

    Schek, Gabriele; Silva, Mara Regina Santos da; Lacharité, Carl; Bueno, Maria Emilia Nunes

    2016-01-01

    To identify the conceptions of professionals regarding interfamily violence against children and adolescents. A qualitative study conducted with 15 professionals who had taken children and adolescents under their care as a result of interfamily violence. Data were collected between November, 2013, and March, 2015, through semi-structured interviews. Data were organized and analyzed using the Textual Discourse Analysis technique. The professional discourse highlighted that some legal aspects regarding the handling of interfamily violence against children and adolescents are neglected; an omission supported by the justification of professionals to preserve the family. We highlight the confrontation between the concept of family as a caregiver and the family that commits violence against children, in addition to the positioning of professionals, which does not include the family or the aggressor in the intervention process in facing situations of interfamily violence attended to by the services. Acting against interfamily violence requires professionals to do away with some pre-established concepts in ordee to put the actual needs of victims and families into evidence. Identificar, com base no discurso dos profissionais, suas concepções a respeito da violência intrafamiliar contra crianças e adolescentes. Estudo qualitativo, realizado com 15 profissionais, que tiveram sob seus cuidados crianças e adolescentes atendidas em decorrência da violência intrafamiliar. Os dados foram coletados entre novembro de 2013 e março de 2015, por meio de entrevistas semiestruturadas. Os dados foram organizados e analisados utilizando a técnica de Análise Textual Discursiva. O discurso dos profissionais colocou em evidência que alguns aspectos legais em relação ao manejo da violência intrafamiliar contra crianças e adolescentes são negligenciados, omissão respaldada pela justificativa dos profissionais de preservar a família. Destaca-se o confronto entre a concepção de família como cuidadora e a família que violenta os filhos, além do posicionamento dos profissionais, os quais não incluem a família e o agressor nos processos de intervenção frente às situações de violência intrafamiliar atendidas nos serviços. Atuar frente à violência intrafamiliar requer do profissional romper com algumas concepções preestabelecidas para colocar em evidência as reais necessidades de vítimas e famílias.

  5. On Ensino da Astronomia no Ensino Médio sob Diferentes Abordagens Metodológicas

    NASA Astrophysics Data System (ADS)

    Voelzke, Marcos Rincon; Albrecht, Evonir

    2011-12-01

    O presente trabalho, sobre a intervenção de metodologias de ensino, foi desenvolvido na Escola Estadual Colônia dos Pescadores, na cidade de Caraguatatuba - SP, em três turmas do terceiro ano do Ensino Médio, perfazendo um total de 119 educandos, entre 16 e 19 anos. Antes de iniciar-se a intervenção, um questionário de vinte perguntas objetivas e dissertativas foi desenvolvido, aplicado pelo professor da classe, que ministrou as aulas correspondentes. Este questionário foi o mesmo em todas as três classes com o objetivo de diagnosticar o conhecimento prévio dos alunos sobre Astronomia. Começando a intervenção nas turmas, o professor envolvido usou três diferentes metodologias de ensino: (A) em forma de seminários, elaborados e apresentados pelos alunos, nos quais o professor fazia apenas as intervenções necessárias, (B) na forma tradicional, com a ajuda de multimídia para o desenvolvimento das aulas e a terceira (C) a tradicional, fazendo uso exclusivo de lousa e giz. No final do trabalho os alunos responderam o mesmo questionário novamente, de modo que os três métodos utilizados puderam ser comparados. Os resultados apresentados após a intervenção foram melhores que os resultados iniciais indicando a ocorrência de uma aprendizagem significativa. Quando os estudantes foram inicialmente questionados sobre quantos planetas existem no nosso sistema solar, a classe A obteve 39% de respostas certas, a classe B 48% e a classe C 46%, mas após o desenvolvimento das atividades, as classes obtiveram respectivamente 94%, 97 % e 90% de aproveitamento. No término do bimestre, foi sugerido aos educandos que elaborassem uma história em quadrinhos, a qual serviu para averiguar se os conceitos inicialmente observados foram alterados e se novos foram agregados. A análise das histórias foi dividida em três partes: Criatividade; Temas abordados; Emprego correto dos conceitos estudados. Ao final quatorze histórias foram confeccionadas. O aprendizado foi tão significativo que os alunos produzira m histórias em quadrinhos, com informações muito ricas. Outro dado muito importante é que, apesar da Astronomia ser um tema amplamente recomendado, não é ensinado nem em escolas de ensino fundamental nem no ensino médio.

  6. Influences of donor/acceptor ratio on the optical and electrical properties of the D/A alternating model oligomers: A density functional theory study

    NASA Astrophysics Data System (ADS)

    Zheng, Hao; Zhao, Yang; Song, Ming-Xing; Wang, Jin; Chen, Li-Qiao; Sun, Lei; Bai, Fu-Quan

    2018-06-01

    We adopted an ingenious method that cut out the DA alternating oligomers from the corresponding DA alternating copolymers. From analyzing the orbital compositions of the HOMOs and LUMOs as well as the reorganization energies, we found the level of charge transfer is increased with the increasing of D/A ratio, but ionization potentials and electron affinities show a contrary trend. Moreover, with the greater ratio, the trend in the nearness of two transitions results in broadening the absorption band in the visible range. That is why experimentally improving the ratio is beneficial for the copolymers used as the p-type materials in the BHJ solar cells. This method is impossible to take the real copolymer system, however, it could provide a strategy to avoid the limitation of the theory level and perform reliable result to study the intrinsic properties of DA alternating copolymers, which can provide a guidance to experimental works.

  7. Organic Donor-Acceptor Complexes as Novel Organic Semiconductors.

    PubMed

    Zhang, Jing; Xu, Wei; Sheng, Peng; Zhao, Guangyao; Zhu, Daoben

    2017-07-18

    Organic donor-acceptor (DA) complexes have attracted wide attention in recent decades, resulting in the rapid development of organic binary system electronics. The design and synthesis of organic DA complexes with a variety of component structures have mainly focused on metallicity (or even superconductivity), emission, or ferroelectricity studies. Further efforts have been made in high-performance electronic investigations. The chemical versatility of organic semiconductors provides DA complexes with a great number of possibilities for semiconducting applications. Organic DA complexes extend the semiconductor family and promote charge separation and transport in organic field-effect transistors (OFETs) and organic photovoltaics (OPVs). In OFETs, the organic complex serves as an active layer across extraordinary charge pathways, ensuring the efficient transport of induced charges. Although an increasing number of organic semiconductors have been reported to exhibit good p- or n-type properties (mobilities higher than 1 or even 10 cm 2 V -1 s -1 ), critical scientific challenges remain in utilizing the advantages of existing semiconductor materials for more and wider applications while maintaining less complicated synthetic or device fabrication processes. DA complex materials have revealed new insight: their unique molecular packing and structure-property relationships. The combination of donors and acceptors could offer practical advantages compared with their unimolecular materials. First, growing crystals of DA complexes with densely packed structures will reduce impurities and traps from the self-assembly process. Second, complexes based on the original structural components could form superior mixture stacking, which can facilitate charge transport depending on the driving force in the coassembly process. Third, the effective use of organic semiconductors can lead to tunable band structures, allowing the operation mode (p- or n-type) of the transistor to be systematically controlled by changing the components. Finally, theoretical calculations based on cocrystals with unique stacking could widen our understanding of structure-property relationships and in turn help us design high-performance semiconductors based on DA complexes. In this Account, we focus on discussing organic DA complexes as a new class of semiconducting materials, including their design, growth methods, packing modes, charge-transport properties, and structure-property relationships. We have also fabricated and investigated devices based on these binary crystals. This interdisciplinary work combines techniques from the fields of self-assembly, crystallography, condensed-matter physics, and theoretical chemistry. Researchers have designed new complex systems, including donor and acceptor compounds that self-assemble in feasible ways into highly ordered cocrystals. We demonstrate that using this crystallization method can easily realize ambipolar or unipolar transport. To further improve device performance, we propose several design strategies, such as using new kinds of donors and acceptors, modulating the energy alignment of the donor (ionization potential, IP) and acceptor (electron affinity, EA) components, and extending the π-conjugated backbones. In addition, we have found that when we use molecular "doping" (2:1 cocrystallization), the charge-transport nature of organic semiconductors can be switched from hole-transport-dominated to electron-transport-dominated. We expect that the formation of cocrystals through the complexation of organic donor and acceptor species will serve as a new strategy to develop semiconductors for organic electronics with superior performances over their corresponding individual components.

  8. Sarcopenic obesity or obese sarcopenia: A cross talk between age-associated adipose tissue and skeletal muscle inflammation as a main mechanism of the pathogenesis.

    PubMed

    Kalinkovich, Alexander; Livshits, Gregory

    2017-05-01

    Sarcopenia, an age-associated decline in skeletal muscle mass coupled with functional deterioration, may be exacerbated by obesity leading to higher disability, frailty, morbidity and mortality rates. In the combination of sarcopenia and obesity, the state called sarcopenic obesity (SOB), some key age- and obesity-mediated factors and pathways may aggravate sarcopenia. This review will analyze the mechanisms underlying the pathogenesis of SOB. In obese adipose tissue (AT), adipocytes undergo hypertrophy, hyperplasia and activation resulted in accumulation of pro-inflammatory macrophages and other immune cells as well as dysregulated production of various adipokines that together with senescent cells and the immune cell-released cytokines and chemokines create a local pro-inflammatory status. In addition, obese AT is characterized by excessive production and disturbed capacity to store lipids, which accumulate ectopically in skeletal muscle. These intramuscular lipids and their derivatives induce mitochondrial dysfunction characterized by impaired β-oxidation capacity and increased reactive oxygen species formation providing lipotoxic environment and insulin resistance as well as enhanced secretion of some pro-inflammatory myokines capable of inducing muscle dysfunction by auto/paracrine manner. In turn, by endocrine manner, these myokines may exacerbate AT inflammation and also support chronic low grade systemic inflammation (inflammaging), overall establishing a detrimental vicious circle maintaining AT and skeletal muscle inflammation, thus triggering and supporting SOB development. Under these circumstances, we believe that AT inflammation dominates over skeletal muscle inflammation. Thus, in essence, it redirects the vector of processes from "sarcopenia→obesity" to "obesity→sarcopenia". We therefore propose that this condition be defined as "obese sarcopenia", to reflect the direction of the pathological pathway. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Synergistic effect of high and low molecular weight molecules in the foamability and foam stability of sparkling wines.

    PubMed

    Coelho, Elisabete; Reis, Ana; Domingues, M Rosário M; Rocha, Sílvia M; Coimbra, Manuel A

    2011-04-13

    The foam of sparkling wines is a key parameter of their quality. However, the compounds that are directly involved in foam formation and stabilization are not yet completely established. In this work, seven sparkling wines were produced in Bairrada appellation (Portugal) under different conditions and their foaming properties evaluated using a Mosalux-based device. Fractionation of the sparkling wines into four independent fractions, (1) high molecular weight material, with molecular weight higher than 12 kDa (HMW), (2) hydrophilic material with molecular weigh between 1 and 12 kDa (AqIMW), (3) hydrophobic material with molecular weigh between 1 and 12 kDa (MeIMW), and (4) hydrophobic material with a molecular weight lower than 1 kDa (MeLMW), allowed the observation that the wines presenting the lower foam stability were those that presented lower amounts of the MeLMW fraction. The fraction that presented the best foam stability was HMW. When HMW is combined with MeLMW fraction, the foam stability largely increased. This increase was even larger, approaching the foam stability of the sparkling wine, when HMW was combined with the less hydrophobic subfraction of MeLMW (fraction 3). Electrospray tandem mass spectrometry (ESI-MS/MS) of fraction 3 allowed the assignment of polyethylene glycol oligomers (n = 5-11) and diethylene glycol 8-hydroxytridecanoate glyceryl acetate. To observe if these molecules occur in sparkling wine foam, the MeLMW was recovered directly from the sparkling wine foam and was also analyzed by ESI-MS/MS. The presence of monoacylglycerols of palmitic and stearic acids, as well as four glycerylethylene glycol fatty acid derivatives, was observed. These surface active compounds are preferentially partitioned by the sparkling wine foam rather than the liquid phase, allowing the inference of their role as key components in the promotion and stabilization of sparkling wine foam.

  10. The occurrence of domoic acid linked to a toxic diatom bloom in a new potential vector: the tunicate Pyura chilensis (piure).

    PubMed

    López-Rivera, Américo; Pinto, Maricela; Insinilla, Andrea; Suárez Isla, Benjamín; Uribe, Eduardo; Alvarez, Gonzalo; Lehane, Mary; Furey, Ambrose; James, Kevin J

    2009-11-01

    The tunicate Pyura chilensis (Molina, 1782); Phylum Chordata; Subphylum Urochordata; Class Ascidiacea, common local name "piure" or sea squirt; a filter-feeder (plankton and suspended particles) sessile species; may play an important role in monitoring domoic acid (DA) the principal toxic component of Amnesic Shellfish Poisoning (ASP). Significant DA concentrations have been determined in tunicate samples, collected during a recent ASP outbreak in Bahía Inglesa, an important scallop (Argopecten purpuratus) farming area. Several infaunal species were tested for the presence of DA, in addition to the usual scallop monitoring programme. DA was found at sub-toxic levels in filtering bivalves such as mussels (Mytilus chilensis), large mussels (Aulacomya ater) and clams (Protothaca thaca) (6.4, 5.4 and 4.7 microg DA/g tissue respectively). Of particular interest was the observation of significant accumulations of toxic Pseudo-nitzschia sp. diatoms in the internal siphon and atrium spaces of the tunicate. Toxin distribution within major tunicate organs was heterogeneous with 8.7-15.5 microg DA/g in edible tissues, 14.9-17.9 microg DA/g in the fecal material and 13.6-32.7 microg DA/g in the gut content. DA was determined by HPLC-UV and confirmed by diode-array detection and LC-MS/MS analysis. This is the first report of the presence of DA in a tunicate that is regularly consumed by coastal populations. These results confirm the need to include these organisms in sanitation programs for marine toxins.

  11. Biodynamic Response to Windblast.

    DTIC Science & Technology

    1975-07-01

    750 noeuda. Lea rioultata atatistiquea globaux donnent -47 ijectiona inortellea (18 %), 209 of riusaies (82 %), il: pilate errivant vivant mu aol...On entend par 6jection riummie 1. fait quo ise pilot* arrive vivant au sob K sans tenir compto dos blemauroo 6ventuellos qulil priaents. Dana notre

  12. Forgetting in immediate serial recall: decay, temporal distinctiveness, or interference?

    PubMed

    Oberauer, Klaus; Lewandowsky, Stephan

    2008-07-01

    Three hypotheses of forgetting from immediate memory were tested: time-based decay, decreasing temporal distinctiveness, and interference. The hypotheses were represented by 3 models of serial recall: the primacy model, the SIMPLE (scale-independent memory, perception, and learning) model, and the SOB (serial order in a box) model, respectively. The models were fit to 2 experiments investigating the effect of filled delays between items at encoding or at recall. Short delays between items, filled with articulatory suppression, led to massive impairment of memory relative to a no-delay baseline. Extending the delays had little additional effect, suggesting that the passage of time alone does not cause forgetting. Adding a choice reaction task in the delay periods to block attention-based rehearsal did not change these results. The interference-based SOB fit the data best; the primacy model overpredicted the effect of lengthening delays, and SIMPLE was unable to explain the effect of delays at encoding. The authors conclude that purely temporal views of forgetting are inadequate. Copyright (c) 2008 APA, all rights reserved.

  13. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barrett, Christopher A.; Martinez, Alonzo; McNamara, Bruce K.

    International Atom Energy Agency (IAEA) safeguard verification measures in gaseous centrifuge enrichment plants (GCEPs) rely on environmental sampling, non-destructive assay (NDA), and destructive assay (DA) sampling and analysis to determine uranium enrichment. UF6 bias defect measurements are made by DA sampling and analysis to assure that enrichment is consistent with declarations. DA samples are collected from a limited number of cylinders for high precision, offsite mass spectrometer analysis. Samples are typically drawn from a sampling tap into a UF6 sample bottle, then packaged, sealed, and shipped under IAEA chain of custody to an offsite analytical laboratory. Future DA safeguard measuresmore » may require improvements in efficiency and effectiveness as GCEP capacities increase and UF6 shipping regulations become increasingly more restrictive. The Pacific Northwest National Laboratory (PNNL) DA sampler concept and Laser Ablation Absorption Ratio Spectrometry (LAARS) assay method are under development to potentially provide DA safeguard tools that increase inspection effectiveness and reduce sample shipping constraints. The PNNL DA sampler concept uses a handheld sampler to collect DA samples for either onsite LAARS assay or offsite laboratory analysis. The DA sampler design will use a small sampling planchet that is coated with an adsorptive film to collect controlled quantities of UF6 gas directly from a cylinder or process sampling tap. Development efforts are currently underway at PNNL to enhance LAARS assay performance to allow high-precision onsite bias defect measurements. In this paper, we report on the experimental investigation to develop adsorptive films for the PNNL DA sampler concept. These films are intended to efficiently capture UF6 and then stabilize the collected DA sample prior to onsite LAARS or offsite laboratory analysis. Several porous material composite films were investigated, including a film designed to maximize the chemical adsorption and binding of gaseous UF6 onto the sampling planchet.« less

  14. Development of antibodies against the rat brain somatostatin receptor.

    PubMed

    Theveniau, M; Rens-Domiano, S; Law, S F; Rougon, G; Reisine, T

    1992-05-15

    Somatostatin (SRIF) is a neurotransmitter in the brain involved in the regulation of motor activity and cognition. It induces its physiological actions by interacting with receptors. We have developed antibodies against the receptor to investigate its structural properties. Rabbit polyclonal antibodies were generated against the rat brain SRIF receptor. These antibodies (F4) were able to immunoprecipitate solubilized SRIF receptors from rat brain and the cell line AtT-20. The specificity of the interaction of these antibodies with SRIF receptors was further demonstrated by immunoblotting. F4 detected SRIF receptors of 60 kDa from rat brain and adrenal cortex and the cell lines AtT-20, GH3, and NG-108, which express high densities of SRIF receptors. They did not detect immunoreactive material from rat liver or COS-1, HEPG, or CRL cells, which do not express functional SRIF receptors. In rat brain, 60-kDa immunoreactivity was detected by F4 in the hippocampus, cerebral cortex, and striatum, which have high densities of SRIF receptors. However, F4 did not interact with proteins from cerebellum and brain stem, which express few SRIF receptors. Immunoreactive material cannot be detected in rat pancreas or pituitary, which have been reported to express a 90-kDa SRIF receptor subtype. The selective detection of 60-kDa SRIF receptors by F4 indicates that the 60- and 90-kDa SRIF receptor subtypes are immunologically distinct. The availability of antibodies that selectively detect native and denatured brain SRIF receptors provides us with a feasible approach to clone the brain SRIF receptor gene(s).

  15. Preparation of Cu2O-Reduced Graphene Nanocomposite Modified Electrodes towards Ultrasensitive Dopamine Detection

    PubMed Central

    He, Quanguo; Liu, Jun; Liu, Xiaopeng; Li, Guangli; Deng, Peihong; Liang, Jing

    2018-01-01

    Cu2O-reduced graphene oxide nanocomposite (Cu2O-RGO) was used to modify glassy carbon electrodes (GCE), and applied for the determination of dopamine (DA). The microstructure of Cu2O-RGO nanocomposite material was characterized by scanning electron microscope. Then the electrochemical reduction condition for preparing Cu2O-RGO/GCE and experimental conditions for determining DA were further optimized. The electrochemical behaviors of DA on the bare electrode, RGO- and Cu2O-RGO-modified electrodes were also investigated using cyclic voltammetry in phosphate-buffered saline solution (PBS, pH 3.5). The results show that the oxidation peaks of ascorbic acid (AA), dopamine (DA), and uric acid (UA) could be well separated and the peak-to-peak separations are 204 mV (AA-DA) and 144 mV (DA-UA), respectively. Moreover, the linear response ranges for the determination of 1 × 10−8 mol/L~1 × 10−6 mol/L and 1 × 10−6 mol/L~8 × 10−5 mol/L with the detection limit 6.0 × 10−9 mol/L (S/N = 3). The proposed Cu2O-RGO/GCE was further applied to the determination of DA in dopamine hydrochloride injections with satisfactory results. PMID:29329206

  16. Improving decision making about clinical trial participation - a randomised controlled trial of a decision aid for women considering participation in the IBIS-II breast cancer prevention trial.

    PubMed

    Juraskova, I; Butow, P; Bonner, C; Bell, M L; Smith, A B; Seccombe, M; Boyle, F; Reaby, L; Cuzick, J; Forbes, J F

    2014-07-08

    Decision aids may improve informed consent in clinical trial recruitment, but have not been evaluated in this context. This study investigated whether decision aids (DAs) can reduce decisional difficulties among women considering participation in the International Breast Cancer Intervention Study-II (IBIS-II) trial. The IBIS-II trial investigated breast cancer prevention with anastrazole in two cohorts: women with increased risk (Prevention), and women treated for ductal carcinoma in situ (DCIS). Australia, New Zealand and United Kingdom participants were randomised to receive a DA (DA group) or standard trial consent materials (control group). Questionnaires were completed after deciding about participation in IBIS-II (post decision) and 3 months later (follow-up). Data from 112 Prevention and 34 DCIS participants were analysed post decision (73 DA; 73 control); 95 Prevention and 24 DCIS participants were analysed at follow-up (58 DA; 61 control). There was no effect on the primary outcome of decisional conflict. The DCIS-DA group had higher knowledge post decision, and the Prevention-DA group had lower decisional regret at follow-up. This was the first study to evaluate a DA in the clinical trial setting. The results suggest DAs can potentially increase knowledge and reduce decisional regret about clinical trial participation.

  17. Fabrication of 3D honeycomb-like porous polyurethane-functionalized reduced graphene oxide for detection of dopamine.

    PubMed

    Vilian, A T Ezhil; An, Suyeong; Choe, Sang Rak; Kwak, Cheol Hwan; Huh, Yun Suk; Lee, Jonghwi; Han, Young-Kyu

    2016-12-15

    A three dimensional reduced graphene oxide/polyurethane (RGO-PU) porous material with connected pores was prepared by physical adsorption of RGO onto the surface of porous PU. The porous PU was prepared by directional melt crystallization of a solvent, which produced high pores with controlled orientation. The prepared RGO-PU was characterized by scanning electron microscopy, spectroscopy and electro-chemical methods. The RGO-PU porous material revealed better electrochemical performance, which might be attributed to the robust structure, superior conductivity, large surface area, and good flexibility. Differential pulse voltammetry (DPV) analysis of DA using the RGO-PU exhibited a linear response range over a wide DA concentration of 100-1150pM, with the detection limit of 1pM. This sensor exhibited outstanding anti-interference ability towards co-existing molecules with good stability, sensitivity, and reproducibility. Furthermore, the fabricated sensor was successfully applied for the quantitative analysis of DA in human serum and urine samples with acceptable recovery, which indicates its feasibility for practical application. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. A Clinical Evaluation Denture Adhesives Used by Patients With Xerostomia

    PubMed Central

    Bogucki, Zdzislaw A.; Napadlek, Piotr; Dabrowa, Tomasz

    2015-01-01

    Abstract The purpose of study was to analyze the participants’ opinions concerning the effectiveness of 6 denture adhesives (DA). The study group included 60 participants. Criteria for selecting the patients were as follows: reduced retention and stabilization of maxillary complete dentures and xerostomia. These features were evaluated on basis of clinical examination and standard sialometry tests (u-SFR). Retention of maxillary dentures was scored by modified Kapur index before application of DA. All participants were divided randomly into 6 groups regarding the use of the 6 DA during a 6-month period. After this time, participants completed an HRQL questionnaire. DA noticeably improved retention and stabilization of maxillary complete dentures. DA in the glue form had the best retention effectiveness in participants with xerostomia. These materials are difficult to clean from the denture base. The data are presented in tables and figures. The results of the study collected positive influence of adhesives on retention of dentures in xerostomia patients. The cleaning dentures and denture bearing tissues was difficult. DA help in the use of prostheses, but it is also necessary for the treatment of the causes and symptoms of xerostomia. PMID:25700320

  19. On the Da Vinci size effect in tensile strengths of nanowires: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Zhao, Ziyu; Liu, Jinxing; Soh, Ai Kah

    2018-01-01

    In recent decades, size effects caused by grain size, strain gradient, typical defects etc., have been widely investigated. Nevertheless, the dependence of tensile strength on the specimen length, addressed by Da Vinci around 500 hundred years ago, has received rather limited attention, even though it is one unavoidable question to answer if people attempt to bring materials' amazing nano-scale strengths up to macro-level. Therefore, we make efforts to study tensile behaviors of copper nanowires with a common cross-section and various lengths by employing the molecular dynamics simulations. Surprisingly, a strong size effect of Da Vinci type indeed arises. We have shown the influences of lattice orientation, temperature and prescribed notch on such a Da Vinci size effect. Two different theoretical explanations are briefly proposed for a qualitative understanding. Finally, a simple scaling rule is summarized to cover the tendencies observed.

  20. Continuous gradient scaffolds for rapid screening of cell-material interactions and interfacial tissue regeneration

    PubMed Central

    Bailey, Brennan M.; Nail, Lindsay N.; Grunlan, Melissa A.

    2013-01-01

    In tissue engineering, the physical and chemical properties of the scaffold mediates cell behavior including regeneration. Thus, a strategy that permits rapid screening of cell-scaffold interactions is critical. Herein, we have prepared eight “hybrid” hydrogel scaffolds in the form of continuous gradients such that a single scaffold contains spatially varied properties. These scaffolds are based on combining an inorganic macromer [methacrylated star polydimethylsiloxane, PDMSstar-MA] and organic macromer [poly(ethylene glycol)diacrylate, PEG-DA] as well both aqueous and organic fabrication solvents. Having previously demonstrated its bioactivity and osteoinductivity, PDMSstar-MA is a particularly powerful component to incorporate into instructive gradient scaffolds based on PEG-DA. The following parameters were varied to produce the different gradients or gradual transitions in: (1) the wt% ratio of PDMSstar-MA to PEG-DA macromers, (2) the total wt% macromer concentration, (3) the number average molecular weight (Mn) of PEG-DA and (4) the Mn of PDMSstar-MA. Upon dividing each scaffold into four “zones” perpendicular to the gradient, we were able to demonstrate the spatial variation in morphology, bioactivity, swelling and modulus. Among these gradient scaffolds are those in which swelling and modulus are conveniently decoupled. In addition to rapid screening of cell-material interactions, these scaffolds are well-suited for regeneration of interfacial tissues (e.g. osteochondral tissues) that transition from one tissue type to another. PMID:23707502

  1. Criteria for recognition and taphonomy of coprolites from the Serra da Galga Member, Marília Formation (Upper Cretaceous), Minas Gerais, Brazil

    NASA Astrophysics Data System (ADS)

    de Oliveira, Fábio Antônio; Santucci, Rodrigo Miloni

    2017-10-01

    The Cretaceous sedimentary rocks from Uberaba, Minas Gerais, have provided a rich vertebrate fauna unearthed from rocks of the Serra da Galga Member, Marília Formation, Bauru Group, of Maastrichtian age. Together with these fossils, a large number of coprolites have also been found from two main localities, here called the Peirópolis and Serra da Galga sites. During field trips carried out in the last few years, 340 samples have been collected, prepared, and analyzed in laboratory. By using parameters such as weight, density, mineralogical composition, and content, we identified 199 coprolites and 141 inorganic nodules (pseudocoprolites). The coprolites have been divided into four morphotypes, which suggest their producers varied in feeding strategies and size. The taphonomic study, based on morphological characters such as wear, presence of pebbles or pebble marks, and desiccation cracks, suggests they underwent temporal and spatial-mixing, and that the material from the Peirópolis Site were transported essentially by alluvial processes (alluvial fans), whereas the material from the Serra da Galga Site were reworked mainly by fluvial streams. The same taphonomic processes may well have affected other fossils from these sites, which are highly abundant in the rocks of this area. Because of that, this taphonomic aspect becomes an important parameter to be taken into account in future studies on the biota of the region.

  2. Ultrafast Self-Healing Nanocomposites via Infrared Laser and Their Application in Flexible Electronics.

    PubMed

    Wu, Shuwen; Li, Jinhui; Zhang, Guoping; Yao, Yimin; Li, Gang; Sun, Rong; Wong, Chingping

    2017-01-25

    The continuous evolution toward flexible electronics with mechanical robust property and restoring structure simultaneously places high demand on a set of polymeric material substrate. Herein, we describe a composite material composed of a polyurethane based on Diels-Alder chemistry (PU-DA) covalently linked with functionalized graphene nanosheets (FGNS), which shows mechanical robust and infrared (IR) laser self-healing properties at ambient conditions and is therefore suitable for flexible substrate applications. The mechanical strength can be tuned by varying the amount of FGNS and breaking strength can reach as high as 36 MPa with only 0.5 wt % FGNS loading. On rupture, the initial mechanical properties are restored with more than 96% healing efficiency after 1 min irradiation time by 980 nm IR laser. Especially, this is the highest value of healing efficiency reported in the self-healable materials based on DA chemistry systems until now, and the composite exhibits a high volume resistivity up to 5.6 × 10 11 Ω·cm even the loading of FGNS increased to 1.0 wt %. Moreover, the conductivity of the broken electric circuit which was fabricated by silver paste drop-cast on the healable composite substrate was completely recovered via IR laser irradiating bottom substrate mimicking human skin. These results demonstrate that the FGNS-PU-DA nanocomposite can be used as self-healing flexible substrate for the next generation of intelligent flexible electronics.

  3. Air Force Information Publishing Service 902-S Procurement Program

    DTIC Science & Technology

    1993-03-22

    34- ^ D. 0. Cooks Director 65 This J>age was- left out of original document U» DEPARTMENT OF THE NAVY THE ASSISTAMT SECRETARY Of THC MAW (Wwwth...including Technical and’Management Factor and Sob- Factor personnel, and Cost Factor Evaluation Team; CBD advertising; Bidden Conference; and

  4. Electrochemical layer-by-layer approach to fabricate mechanically stable platinum black microelectrodes using a mussel-inspired polydopamine adhesive.

    PubMed

    Kim, Raeyoung; Nam, Yoonkey

    2015-04-01

    Platinum black (PtBK) has long been used for microelectrode fabrication owing to its high recording performance of neural signals. The porous structure of PtBK enlarges the surface area and lowers the impedance, which results in background noise reduction. However, the brittleness of PtBK has been a problem in practice. In this work, we report mechanically stable PtBK microelectrodes using a bioinspired adhesive film, polydopamine (pDA), while maintaining the low impedance of PtBK. The pDA layer was incorporated into the PtBK structure through electrochemical layer-by-layer deposition. Varying the number of layers and the order of materials, multi-layered pDA-PtBK hybrids were fabricated and the electrical properties, both impedance and charge injection limit, were evaluated. Multilayered pDA-PtBK hybrids had electrical impedances as low as PtBK controls and charge injection limit twice larger than controls. For the 30 min-ultrasonication agitation test, impedance levels rarely changed for some of the pDA-PtBK hybrids indicating that the pDA improved the mechanical property of the PtBK structures. The pDA-PtBK hybrid microelectrodes readily recorded neural signals of cultured hippocampal neurons, where background noise levels and signal-to-noise were 2.43 ∼ 3.23 μVrms and 28.4 ∼ 69.1, respectively. The developed pDA-PtBK hybrid microelectrodes are expected to be applicable to neural sensors for neural prosthetic studies.

  5. Improving decision making about clinical trial participation – a randomised controlled trial of a decision aid for women considering participation in the IBIS-II breast cancer prevention trial

    PubMed Central

    Juraskova, I; Butow, P; Bonner, C; Bell, M L; Smith, A B; Seccombe, M; Boyle, F; Reaby, L; Cuzick, J; Forbes, J F

    2014-01-01

    Background: Decision aids may improve informed consent in clinical trial recruitment, but have not been evaluated in this context. This study investigated whether decision aids (DAs) can reduce decisional difficulties among women considering participation in the International Breast Cancer Intervention Study-II (IBIS-II) trial. Methods: The IBIS-II trial investigated breast cancer prevention with anastrazole in two cohorts: women with increased risk (Prevention), and women treated for ductal carcinoma in situ (DCIS). Australia, New Zealand and United Kingdom participants were randomised to receive a DA (DA group) or standard trial consent materials (control group). Questionnaires were completed after deciding about participation in IBIS-II (post decision) and 3 months later (follow-up). Results: Data from 112 Prevention and 34 DCIS participants were analysed post decision (73 DA; 73 control); 95 Prevention and 24 DCIS participants were analysed at follow-up (58 DA; 61 control). There was no effect on the primary outcome of decisional conflict. The DCIS–DA group had higher knowledge post decision, and the Prevention-DA group had lower decisional regret at follow-up. Conclusions: This was the first study to evaluate a DA in the clinical trial setting. The results suggest DAs can potentially increase knowledge and reduce decisional regret about clinical trial participation. PMID:24892447

  6. Surface Layer Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (SL-MALDI-ToF-MS) Analysis of Polymer Blend Surface Composition

    NASA Astrophysics Data System (ADS)

    Hill, Jacob A.

    The composition of a polymer blend is generally different at the surface than in the bulk and the gradient in composition with depth has important implications for surface properties. The determination of the surface composition presents various challenges which continue to prompt the development of new techniques for quantifying the composition. Here the technique of surface layer matrix-assisted laser desorption ionization time-of-flight mass spectrometry (SL-MALDI-ToF-MS) has been further developed to address four specific questions of polymer blend surface behavior within the general category of surface composition determination. The first question is how chain length disparity affects surface segregation in the case that the disparity is quite small. While such segregation is known for blends containing low molecular weight additives or systems with large polydispersity, it has not been reported for anionically polymerized polymers that are viewed, in practice, as monodisperse. For 6 kDa polystyrene the number average molecular weight (Mn) at the surface is ca. 300 Da (5%) lower than that in the bulk and for 7 kDa polymethyl methacrylate the shift is ca. 500 Da. The second question is how chain-end functionalization effects not the location of chain ends at the surface, but rather the prevalence at the surface of any part of a chain having an end functionalization. A key issue of such an approach is understanding precisely where the functionalities ultimately reside and how this functionalization shifts the balance of forces that determine the distribution of chains with depth. The surface of a blend of 6 kDa polystyrene and 6 kDa polystyrene functionalized with hydroxymethyl ends is not only depleted of the higher energy end groups, but is depleted of any segments belonging to the functionalized chains. This is demonstrated using SL-MALDI-ToF-MS, which detects entire chains that have any repeat unit at the outer surface, and requires no labelling. This study was extended to the surfaces of blends of 6 kDa polystyrene and 6 kDa polystyrene functionalized with hydroxyethyl ends. Blends of all compositions less than 90 wt. % functionalized chains showed depletion. Finally, the challenge of determining lateral variations in the surface composition has been addressed with the development of SL-MALDI-ToF-MS imaging (SL-MALDI-ToF-MSI). Key to developing imaging capability was improving the lateral uniformity of the matrix deposition. This uniformity was achieved using solvent free sublimation of matrix and salt onto the sample's surface. The capabilities of SL-MALDI-ToF-MSI were demonstrated by imaging the absence of material due to masking during material deposition, mechanical scribing or solvent perturbation at the surface of low molecular weight poly(methyl methacrylate) and polystyrene thin films. SL-MALDI-ToF MSI was made possible through the first uniform, solvent free simultaneous sublimation of matrix and salt onto the material's surface.

  7. A new species of Eidmanacris Chopard, 1956, with notes on its distribution in Brazilian caves (Phalangopsidae, Luzarinae).

    PubMed

    Bolfarini, Marcio P

    2016-02-23

    The genus Eidmanacris comprises 19 species distributed through Brazil, Bolivia ad Paraguay. In Brazil, the genus has a broad distribution, but its occurrence in Brazilian caves is poorly known; the only species recorded is E. alboannulata for the cave "Gruta da Toca", Itirapina municipality, São Paulo State. In this study I describe a species, E. lencionii Bolfarini, n. sp., with a discussion on its distribution in Brazilian caves, and its relation with the hypogean environment. The type material is deposited in the Museu de Zoologia da Universidade de São Paulo (MZSP) and the Laboratório de Estudos Subterrâneos da Universidade Federal de São Carlos (LES/UFSCar).

  8. Environmental benefits and concerns on safety: communicating latest results on nanotechnology safety research-the project DaNa2.0.

    PubMed

    Kühnel, D; Marquardt, C; Nau, K; Krug, H F; Paul, F; Steinbach, C

    2017-04-01

    The use of nanotechnology and advanced materials promises to revolutionise many areas of technology and improve our daily life. In that respect, many positive effects on the environment are expected, either directly, by developing new technologies for remediation, filtering techniques or energy generation, or indirectly, by e.g. saving resources due to lower consumption of raw materials, or lower energy and fuel consumption due to reduced weight of vehicles. However, such beneficial effects of new technologies are often confronted by concerns regarding the safety of novel substances or materials. During the past 10 years, great effort has been put into research on potential hazards of nanomaterials towards environmental organisms. As the methodology for reliable assessment of nanomaterials was immature, many studies reporting contradictory results have been published, hindering both risk assessment for nanomaterials, as well as the knowledge communication to all involved stakeholders. Thus, DaNa 2.0 serves as a platform to implement trusted knowledge on nanomaterials for an objective discussion.

  9. Amperometric Detection in Microchip Electrophoresis Devices: Effect of Electrode Material and Alignment on Analytical Performance

    PubMed Central

    Fischer, David J.; Hulvey, Matthew K.; Regel, Anne R.; Lunte, Susan M.

    2012-01-01

    The fabrication and evaluation of different electrode materials and electrode alignments for microchip electrophoresis with electrochemical (EC) detection is described. The influences of electrode material, both metal and carbon-based, on sensitivity and limits of detection (LOD) were examined. In addition, the effects of working electrode alignment on analytical performance (in terms of peak shape, resolution, sensitivity, and LOD) were directly compared. Using dopamine (DA), norepinephrine (NE), and catechol (CAT) as test analytes, it was found that pyrolyzed photoresist electrodes with end-channel alignment yielded the lowest limit of detection (35 nM for DA). In addition to being easier to implement, end-channel alignment also offered better analytical performance than off-channel alignment for the detection of all three analytes. In-channel electrode alignment resulted in a 3.6-fold reduction in peak skew and reduced peak tailing by a factor of 2.1 for catechol in comparison to end-channel alignment. PMID:19802847

  10. Mussel-inspired functionalization of graphene for synthesizing Ag-polydopamine-graphene nanosheets as antibacterial materials

    NASA Astrophysics Data System (ADS)

    Zhang, Zhe; Zhang, Jing; Zhang, Bailin; Tang, Jilin

    2012-12-01

    Mussels have been shown to attach to virtually all types of inorganic and organic surfaces via their adhesive proteins. The adhesive proteins secreted by mussels contain high concentrations of catechol and amine functional groups, which have similar functional groups with polydopamine (PDA). Inspired by mussels, a mild and environmentally friendly method was used to synthesize Ag nanoparticles (Ag NPs) on functionalized PDA-graphene nanosheets (PDA-GNS) with uniform and high dispersion. First, a uniform layer of PDA was coated on graphene oxide (GO) by polymerizing dopamine (DA) at room temperature. During the process GO was reduced by the DA. The PDA layer on the surface of GNS can be used as a nanoscale guide to form uniform Ag NPs on the surface of PDA-GNS. The obtained Ag-PDA-GNS hybrid materials are characterized by atomic force microscopy, transmission electron microscopy, UV-vis spectroscopy, Raman spectroscopy, X-ray photo-electron spectroscopy, X-ray diffraction, and thermal gravimetric analysis. The resultant Ag-PDA-GNS hybrid materials exhibited strong antibacterial properties to both Gram-negative and Gram-positive bacteria due to the synergistic effect of GNS and Ag NPs.Mussels have been shown to attach to virtually all types of inorganic and organic surfaces via their adhesive proteins. The adhesive proteins secreted by mussels contain high concentrations of catechol and amine functional groups, which have similar functional groups with polydopamine (PDA). Inspired by mussels, a mild and environmentally friendly method was used to synthesize Ag nanoparticles (Ag NPs) on functionalized PDA-graphene nanosheets (PDA-GNS) with uniform and high dispersion. First, a uniform layer of PDA was coated on graphene oxide (GO) by polymerizing dopamine (DA) at room temperature. During the process GO was reduced by the DA. The PDA layer on the surface of GNS can be used as a nanoscale guide to form uniform Ag NPs on the surface of PDA-GNS. The obtained Ag-PDA-GNS hybrid materials are characterized by atomic force microscopy, transmission electron microscopy, UV-vis spectroscopy, Raman spectroscopy, X-ray photo-electron spectroscopy, X-ray diffraction, and thermal gravimetric analysis. The resultant Ag-PDA-GNS hybrid materials exhibited strong antibacterial properties to both Gram-negative and Gram-positive bacteria due to the synergistic effect of GNS and Ag NPs. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32092d

  11. Evaluation of the effect of the degree of acetylation on the inflammatory response to 3D porous chitosan scaffolds.

    PubMed

    Barbosa, Judite N; Amaral, Isabel F; Aguas, Artur P; Barbosa, Mário A

    2010-04-01

    The effect of the degree of acetylation (DA) of 3D chitosan (Ch) scaffolds on the inflammatory reaction was investigated. Chitosan porous scaffolds with DAs of 4 and 15% were implanted using a subcutaneous air-pouch model of inflammation. The initial acute inflammatory response was evaluated 24 and 48 h after implantation. To characterize the initial response, the recruitment and adhesion of inflammatory cells to the implant site was studied. The fibrous capsule formation and the infiltration of inflammatory cells within the scaffolds were evaluated for longer implantation times (2 and 4 weeks). Chitosan with DA 15% attracted the highest number of leukocytes to the implant site. High numbers of adherent inflammatory cells were also observed in this material. For longer implantation periods Ch scaffolds with a DA of 15% induced the formation of a thick fibrous capsule and a high infiltration of inflammatory cells within the scaffold. Our results indicate that the biological response to implanted Ch scaffolds was influenced by the DA. Chitosan with a DA of 15% induce a more intense inflammatory response when compared with DA 4% Ch. Because inflammation and healing are interrelated, this result may provide clues for the relative importance of acetyl and amine functional groups in tissue repair and regeneration.

  12. Small-scale solutions. Millennium trailblazers 1: Ashok Khosia.

    PubMed

    Bhatia, R

    1999-01-01

    Development Alternatives (DA) is a nongovernmental organization founded by Ashok Khosla in 1982 that seeks to improve the quality of life for those denied the basics and promote the sustainable use of natural resources in India through the intelligent application of technology. DA focuses on sustainable livelihoods that create several jobs in a village and has by far helped a quarter of a million people. One of its most successful projects can be found in Tikamgarh District where it has trained local villagers to run off-farm enterprises such as paper production. DA is now one of the biggest producers of hand-made paper, producing about 5 tons of paper every month at its plant in Delhi, and 15 tons from its Jhansi plant. DA has also created the most advanced handloom weaving machine called the Flying Shuttle Loom, and a new roofing tile made of microconcrete known as the TARAcrete tile. Aside from creating low cost building materials which has generated immense employment in the housing sector, DA also caters to the larger population through its welfare programs such as the water for life project which ensures water supply in a number of villages. In addition, DA also launched the Delhi Environment Action Network (DEAN) program that is designed to motivate children and others to improve the quality of their neighborhood.

  13. Forgetting in Immediate Serial Recall: Decay, Temporal Distinctiveness, or Interference?

    ERIC Educational Resources Information Center

    Oberauer, Klaus; Lewandowsky, Stephan

    2008-01-01

    Three hypotheses of forgetting from immediate memory were tested: time-based decay, decreasing temporal distinctiveness, and interference. The hypotheses were represented by 3 models of serial recall: the primacy model, the SIMPLE (scale-independent memory, perception, and learning) model, and the SOB (serial order in a box) model, respectively.…

  14. Continuous gradient scaffolds for rapid screening of cell-material interactions and interfacial tissue regeneration.

    PubMed

    Bailey, Brennan M; Nail, Lindsay N; Grunlan, Melissa A

    2013-09-01

    In tissue engineering, the physical and chemical properties of the scaffold mediates cell behavior, including regeneration. Thus a strategy that permits rapid screening of cell-scaffold interactions is critical. Herein, we have prepared eight "hybrid" hydrogel scaffolds in the form of continuous gradients such that a single scaffold contains spatially varied properties. These scaffolds are based on combining an inorganic macromer (methacrylated star polydimethylsiloxane, PDMSstar-MA) and organic macromer (poly(ethylene glycol)diacrylate, PEG-DA) as well as both aqueous and organic fabrication solvents. Having previously demonstrated its bioactivity and osteoinductivity, PDMSstar-MA is a particularly powerful component to incorporate into instructive gradient scaffolds based on PEG-DA. The following parameters were varied to produce the different gradients or gradual transitions in: (1) the wt.% ratio of PDMSstar-MA to PEG-DA macromers, (2) the total wt.% macromer concentration, (3) the number average molecular weight (Mn) of PEG-DA and (4) the Mn of PDMSstar-MA. Upon dividing each scaffold into four "zones" perpendicular to the gradient, we were able to demonstrate the spatial variation in morphology, bioactivity, swelling and modulus. Among these gradient scaffolds are those in which swelling and modulus are conveniently decoupled. In addition to rapid screening of cell-material interactions, these scaffolds are well suited for regeneration of interfacial tissues (e.g. osteochondral tissues) that transition from one tissue type to another. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. Electrochemical layer-by-layer approach to fabricate mechanically stable platinum black microelectrodes using a mussel-inspired polydopamine adhesive

    NASA Astrophysics Data System (ADS)

    Kim, Raeyoung; Nam, Yoonkey

    2015-04-01

    Objective. Platinum black (PtBK) has long been used for microelectrode fabrication owing to its high recording performance of neural signals. The porous structure of PtBK enlarges the surface area and lowers the impedance, which results in background noise reduction. However, the brittleness of PtBK has been a problem in practice. In this work, we report mechanically stable PtBK microelectrodes using a bioinspired adhesive film, polydopamine (pDA), while maintaining the low impedance of PtBK. Approach. The pDA layer was incorporated into the PtBK structure through electrochemical layer-by-layer deposition. Varying the number of layers and the order of materials, multi-layered pDA-PtBK hybrids were fabricated and the electrical properties, both impedance and charge injection limit, were evaluated. Main results. Multilayered pDA-PtBK hybrids had electrical impedances as low as PtBK controls and charge injection limit twice larger than controls. For the 30 min-ultrasonication agitation test, impedance levels rarely changed for some of the pDA-PtBK hybrids indicating that the pDA improved the mechanical property of the PtBK structures. The pDA-PtBK hybrid microelectrodes readily recorded neural signals of cultured hippocampal neurons, where background noise levels and signal-to-noise were 2.43 ∼ 3.23 μVrms and 28.4 ∼ 69.1, respectively. Significance. The developed pDA-PtBK hybrid microelectrodes are expected to be applicable to neural sensors for neural prosthetic studies.

  16. Solid-phase extraction-fluorimetric high performance liquid chromatographic determination of domoic acid in natural seawater mediated by an amorphous titania sorbent.

    PubMed

    Chan, Ivy O M; Tsang, Vic W H; Chu, K K; Leung, S K; Lam, Michael H W; Lau, T C; Lam, Paul K S; Wu, Rudolf S S

    2007-01-30

    The feasibility of using sol-gel amorphous titania (TiO2) as a solid-phase sorbent for the pre-concentration of domoic acid (DA), a potent amnesic shellfish poisoning (ASP) toxin, directly from seawater was explored. The sol-gel titania material is able to adsorb DA from seawater, via the formation of ester-linkage between the carboxylic moieties of DA and the Ti-OH groups on the sorbent surface, at low pH and desorb it at high pH. The chemisorption process is not significantly interfered by the seawater matrix. The optimum pH values for the adsorption and desorption of DA were found to be pH 4 and 11, respectively. The optimal sorbent loading for the batch-type solid-phase extraction of DA was 0.67 mg-TiO2 ng-DA(-1) and adsorption equilibrium was achieved in 2 h at room temperature. The desorbed DA in 500 microL of 0.1 M alkaline borate buffer can be directly derviatized by 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) in aqueous media for fluorimetric HPLC quantification. Analyte recovery, repeatability and detection limit of this titania SPE-fluorimetric HPLC determination are 89%, 6.2% and 120 pg-DA mL(-1) (n=7, P<0.05), respectively, for a sample volume of 30 mL. This titania SPE technique should also be applicable to the pre-concentration of other polar carboxylate- and phosphonate-containing biomolecules and pharmaceuticals in complex and interfering environmental sample matrices.

  17. Surfactant exfoliated 2D hexagonal Boron Nitride (2D-hBN) explored as a potential electrochemical sensor for dopamine: surfactants significantly influence sensor capabilities.

    PubMed

    Khan, Aamar F; Brownson, Dale A C; Foster, Christopher W; Smith, Graham C; Banks, Craig E

    2017-05-21

    Surfactant exfoliated 2D hexagonal Boron Nitride (2D-hBN) nanosheets are explored as a potential electrochemical sensing platform and evaluated towards the electroanalytical sensing of dopamine (DA) in the presence of the common interferents, ascorbic acid (AA) and uric acid (UA). Surfactant exfoliated 2D-hBN nanosheets (2-4 layers) fabricated using sodium cholate in aqueous media are electrically wired via a drop-casting modification process onto disposable screen-printed graphite electrodes (SPEs). We critically evaluate the performance of these 2D-hBN modified SPEs and demonstrate the effect of 'mass coverage' towards the detection of DA, AA and UA. Previous studies utilising surfactant-free (pristine) 2D-hBN modified SPEs have shown a beneficial effect towards the detection of DA, AA and UA when compared to the underlying/unmodified graphite-based electrode. We show that the fabrication route utilised to prepare 2D-hBN is a vital experimental consideration, such that the beneficial effect previously reported is considerably reduced when surfactant exfoliated 2D-hBN is utilised. We demonstrate for the first time, through implementation of control experiments in the form of surfactant modified graphite electrodes, that sodium cholate is a major contributing factor to the aforementioned detrimental behaviour. The significance here is not in the material per se, but the fundamental knowledge of the surfactant and surface coverage changing the electrochemical properties of the material under investigation. Given the wide variety of ionic and non-ionic surfactants that are utilised in the manufacture of novel 2D materials, the control experiments reported herein need to be performed in order to de-convolute the electrochemical response and effectively evaluate the 'underlying surface/surfactant/2D materials' electrocatalytic contribution.

  18. A Single Molecular Diels-Alder Crosslinker for Achieving Recyclable Cross-Linked Polymers.

    PubMed

    Chen, Shengli; Wang, Fenfen; Peng, Yongjin; Chen, Tiehong; Wu, Qiang; Sun, Pingchuan

    2015-09-01

    A triol-functional crosslinker combining the thermoreversible properties of Diels-Alder (DA) adducts in one molecule is designed, synthesized, and used as an ideal substitute of a traditional crosslinker to prepare thermal recyclable cross-linked polyurethanes with excellent mechanical properties and recyclability in a very simple and efficient way. The recycle property of these materials achieved by the DA/retro-DA reaction at a suitable temperature is verified by differential scanning calorimetry and in situ variable temperature solid-state NMR experiments during the cyclic heating and cooling processes. The thermal recyclability and remending ability of the bulk polyurethanes is demonstrated by three polymer processing methods, including hot-press molding, injection molding, and solution casting. It is notable that all the recycled cross-linked polymers display nearly invariable elongation/stress at break compared to the as-synthesized samples. Further end-group functionalization of this single molecular DA crosslinker provides the potential in preparing a wide range of recyclable cross-linked polymers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Thermo-optical and spectroscopic properties of Nd:YAG fine grain ceramics: towards a better performance than the Nd:YAG laser crystals

    NASA Astrophysics Data System (ADS)

    Santos, W. Q.; Benayas, A.; Jaque, D.; García-Solé, J.; Catunda, T.; Jacinto, C.

    2016-02-01

    In this work, we investigated the thermo-optical properties of highly Nd3+ doped YAG ceramics. The normalized lifetime thermal lens method was used to obtain the fluorescence quantum efficiency (η) versus Nd3+ concentration (N t) and to study the energy transfer microparameters C DD and C DA. The N t dependence of η was compared to the results of the previous literature. The C DA found is very similar to those of the previous literature, while the C DD is very different and higher than C DA, although the main dependence of η with N t is assigned to C DA. The figure of merit (η.N t versus N t) indicated a maximum around 3.8 at.% Nd2O3, which in addition to the very low ds/dT value, evidences the YAG ceramic as an excellent material for an ultra-high-power microchip laser system and for devices requiring minimum pump-induced local heating generation.

  20. Poly(ionic liquids) functionalized polypyrrole/graphene oxide nanosheets for electrochemical sensor to detect dopamine in the presence of ascorbic acid.

    PubMed

    Mao, Hui; Liang, Jiachen; Zhang, Haifeng; Pei, Qi; Liu, Daliang; Wu, Shuyao; Zhang, Yu; Song, Xi-Ming

    2015-08-15

    Novel poly(ionic liquids) functionalized polypyrrole/graphene oxide nanosheets (PILs/PPy/GO) were prepared by the polymerization of 1-vinyl-3-ethylimidazole bromide (VEIB) on the surface of N-vinyl imidazolium modified PPy/GO nanosheets. Due to the synergistic effects of GO with well-defined lamellar structures, conductive PPy and biocompatible PILs, PILs/PPy/GO modified glassy carbon electrode (GCE) presented the excellent electrochemical catalytic activity towards dopamine (DA) with good stability, high sensitivity and wide linear range in the present of ascorbic acid (AA) with high concentration. PILs played an essential role for the simultaneous determination of DA and AA in a mixture, whose existence effectively improved the transmission mode of electrons and resulted in the different electrocatalytic performance towards the oxidation of DA and AA. It is indicated that PILs/PPy/GO nanosheets can act as a good steady and sensitive electrode material for the development of improved DA sensors. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Sub-wavelength modulation of χ (2) optical nonlinearity in organic thin films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yan, Yixin; Yuan, Yakun; Wang, Baomin

    Modulating the second-order nonlinear optical susceptibility (χ (2)) of materials at the nanoscale represents an ongoing technological challenge for a variety of integrated frequency conversion and nonlinear nanophotonic applications. Here we exploit the large hyperpolarizability of intermolecular charge transfer states, naturally aligned at an organic semiconductor donor–acceptor (DA) interface, as a means to control the magnitude and sign of χ (2) at the nanoscale. Focusing initially on a single pentacene-C 60 DA interface, we confirm that the charge transfer transition is strongly aligned orthogonal to the heterojunction and find that it is responsible for a large interfacial nonlinearity probed viamore » second harmonic generation that is sufficient to achieve d 33 > 10pm V –1, when incorporated in a non-centrosymmetric DA multilayer stack. Lastly, using grating-shadowed oblique-angle deposition to laterally structure the DA interface distribution in such multilayers subsequently enables the demonstration of a χ (2) grating with 280 nm periodicity, which is the shortest reported to date.« less

  2. Sub-wavelength modulation of χ(2) optical nonlinearity in organic thin films

    NASA Astrophysics Data System (ADS)

    Yan, Yixin; Yuan, Yakun; Wang, Baomin; Gopalan, Venkatraman; Giebink, Noel C.

    2017-01-01

    Modulating the second-order nonlinear optical susceptibility (χ(2)) of materials at the nanoscale represents an ongoing technological challenge for a variety of integrated frequency conversion and nonlinear nanophotonic applications. Here we exploit the large hyperpolarizability of intermolecular charge transfer states, naturally aligned at an organic semiconductor donor-acceptor (DA) interface, as a means to control the magnitude and sign of χ(2) at the nanoscale. Focusing initially on a single pentacene-C60 DA interface, we confirm that the charge transfer transition is strongly aligned orthogonal to the heterojunction and find that it is responsible for a large interfacial nonlinearity probed via second harmonic generation that is sufficient to achieve d33>10 pm V-1, when incorporated in a non-centrosymmetric DA multilayer stack. Using grating-shadowed oblique-angle deposition to laterally structure the DA interface distribution in such multilayers subsequently enables the demonstration of a χ(2) grating with 280 nm periodicity, which is the shortest reported to date.

  3. Sub-wavelength modulation of χ (2) optical nonlinearity in organic thin films

    DOE PAGES

    Yan, Yixin; Yuan, Yakun; Wang, Baomin; ...

    2017-01-27

    Modulating the second-order nonlinear optical susceptibility (χ (2)) of materials at the nanoscale represents an ongoing technological challenge for a variety of integrated frequency conversion and nonlinear nanophotonic applications. Here we exploit the large hyperpolarizability of intermolecular charge transfer states, naturally aligned at an organic semiconductor donor–acceptor (DA) interface, as a means to control the magnitude and sign of χ (2) at the nanoscale. Focusing initially on a single pentacene-C 60 DA interface, we confirm that the charge transfer transition is strongly aligned orthogonal to the heterojunction and find that it is responsible for a large interfacial nonlinearity probed viamore » second harmonic generation that is sufficient to achieve d 33 > 10pm V –1, when incorporated in a non-centrosymmetric DA multilayer stack. Lastly, using grating-shadowed oblique-angle deposition to laterally structure the DA interface distribution in such multilayers subsequently enables the demonstration of a χ (2) grating with 280 nm periodicity, which is the shortest reported to date.« less

  4. Official blame for drivers with very low blood alcohol content: there is no safe combination of drinking and driving.

    PubMed

    Phillips, David P; Sousa, Ana Luiza R; Moshfegh, Rebecca T

    2015-04-01

    Some laboratory studies find that driving is impaired even at blood alcohol content (BAC)=0.01%. However, no real-world traffic studies have investigated whether minimally 'buzzed' drivers (BAC=0.01%) are more likely to be blamed for a crash than are the sober drivers they collide with. To determine whether official blame for a crash increases significantly at BAC=0.01%. We examined the relationship between the driver's BAC and the degree to which he or she was assigned sole official blame (SOB) for the crash. We analysed an official, exhaustive, nationwide US database (Fatality Analysis Reporting System; n=570 731), covering 1994-2011. Even minimally 'buzzed' drivers are 46% (24-72%) more likely to be officially blamed for a crash than are the sober drivers they collide with (χ(2)=20.45; p=0.000006). There is no threshold effect-no sudden transition from blameless to blamed drivers at BAC=0.08% (the US legal limit). Instead, SOB increases smoothly and strongly with BAC (r=0.98 (0.96-0.99) for male drivers, p<0.000001; r=0.99 (0.97-0.99) for female drivers, p<0.000001). This near-linear SOB-to-BAC relationship begins at BAC=0.01% and ends around BAC=0.24%. Our findings persist after controlling for many confounding variables. There appears to be no safe combination of drinking and driving-even minimally 'buzzed' drivers pose increased risk to themselves and to others. Concerns about drunk driving should also be extended to 'buzzed' driving. US legislators should reduce the legal BAC limit, perhaps to 0.05%, as in most European countries. Lowering the legal BAC limit is likely to reduce injuries and save lives. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  5. Does Plan B work? Home range estimations from stored on board and transmitted data sets produced by GPS-telemetry in the Colombian Amazon.

    PubMed

    Cabrera, Jaime A; Molina, Eduardo; González, Tania; Armenteras, Dolors

    2016-12-01

    Telemetry based on Global Positioning Systems (GPS) makes possible to gather large quantities of information in a very fine scale and work with species that were impossible to study in the past. When working with GPS telemetry, the option of storing data on board could be more desirable than the sole satellite transmitted data, due to the increase in the amount of locations available for analysis. Nonetheless, the uncertainty in the retrieving of the collar unit makes satellite-transmitted technologies something to take into account. Therefore, differences between store-on-board (SoB) and satellite-transmitted (IT) data sets need to be considered. Differences between SoB and IT data collected from two lowland tapirs (Tapirus terrestris), were explored by means of the calculation of home range areas by three different methods: the Minimum Convex Polygon (MCP), the Fixed Kernel Density Estimator (KDE) and the Brownian Bridges (BB). Results showed that SoB and IT data sets for the same individual were similar, with fix ranging from 63 % to 85 % respectively, and 16 m to 17 m horizontal errors. Depending on the total number of locations available for each individual, the home ranges estimated showed differences between 2.7 % and 79.3 %, for the 50 % probability contour and between 9.9 % and 61.8 % for the 95 % probability contour. These differences imply variations in the spatial coincidence of the estimated home ranges. We concluded that the use of IT data is not a good option for the estimation of home range areas if the collar settings have not been designed specifically for this use. Nonetheless, geographical representations of the IT based estimators could be of great help to identify areas of use, besides its assistance to locate the collar for its retrieval at the end of the field season and as a proximate backup when collars disappear.

  6. Identification and distribution of sulfate reducing bacteria and sulphur-oxidising bacteria in northern South China Sea

    NASA Astrophysics Data System (ADS)

    Mao, S.; Zhu, X.; Guan, H.; Wu, D.; Wu, N.

    2015-12-01

    Fatty acids are one of the major components in modern marine sediments. It is well known that the saturated short-chain FAs were typically to be from vascular plants, algae, bacteria, and other sources, while the saturated long-chain FAs are the major components found in leaf waxes, suberin, and cutin in terrestrial higher plants. So the lipid biomarkers of fatty acids in Site 4B from Shenhu Area, northern South China Sea were investigated in Recent research supported from the 973 Program (2009CB219506), and the resources of branched fatty acids and monounsaturated fatty acids were mainly discussed. The results reveal that i/a15:0, i/a17:0, 16:1ω5, 18:1ω9 and 10me16:0 are derived from sulfate reducing bacteria (SRB), while 16:1ω7t/c and 18:1ω7 are originated from sulphur-oxidising bacteria (SOB). The biomakers of methanotrophs such as 16:1ω6/8 and 18:1ω6/8 were not detected in the sediments which coincide with more positive carbon isotope values of the fatty acids in the sediments. The stable relationship between SRB and SOB below 97cm in the sediments reflects the relative stable oxidative and reductive depositional environment which may be connected with the sulphur cycle in the sediments, that is carried out as sulfate is reduced to sulfide, and then sulfide is oxidized to sulfate and elemental sulfur, at last elemental sulfur is disproportionated to sulfide and sulfate. The frequently changed relationship of SRB and SOB above 97cm in the sediments indicates intensely changing oxidative and reductive sedimental environment, that may related with diapir structure around Site 4B, which also brings about hydrocarbon seepage leading to increasing biomass at 97cm.

  7. Accident investigation practices in Europe--main responses from a recent study of accidents in industry and transport.

    PubMed

    Roed-Larsen, Sverre; Valvisto, T; Harms-Ringdahl, L; Kirchsteiger, C

    2004-07-26

    Europe has during recent years been shocked by disasters from natural events and technical breakdowns. The consequences have been comprehensive, measured by lost lives, injuries, and material and environmental damage. ESReDA wanted in 2000--by setting up a special expert group on accident investigation--to clarify the state of art of accident investigation practices and to map the use of thoroughly accident investigation in order to learn lessons from past disasters and prevent new ones. The scope was to cover three sectors in the society: transport, production processes and storage of hazardous materials, and energy production. The main method used was a questionnaire, which was sent in 2001 to about 150 organisations. About 50 replies were analysed. The replies showed great variations but also similarities, among others in definition of accident and incident, the objectives of the investigation team, criteria used to start an investigation, the status of the investigation organisation, the flow of information, the composition of the investigation team, and the use of internal or international procedures or rules. Several methods (in total 14 different methods were mentioned) were used for carrying out accident /incident investigations. Most of the respondents were willing to co-operate in one or another way with ESReDA. Although there are important biases in the material, the results from questionnaire are important inputs to the future work of ESReDA Expert group in this field. 3 safety approaches have been identified.

  8. Conceptos básicos sobre el material particulado (PM, por sus siglas en inglés)

    EPA Pesticide Factsheets

    PM significa material particulado. Es una mezcla de partículas sólidas y gotas líquidas que se encuentran en el aire. Estas partículas, como el polvo, la suciedad, el hollín, o el humo, pueden ocasionar daño a la salud y el medioambiente.

  9. Experimental evaluation of new chitin-chitosan graft for duraplasty.

    PubMed

    Pogorielov, M; Kravtsova, A; Reilly, G C; Deineka, V; Tetteh, G; Kalinkevich, O; Pogorielova, O; Moskalenko, R; Tkach, G

    2017-02-01

    Natural materials such as collagen and alginate have promising applications as dural graft substitutes. These materials are able to restore the dural defect and create optimal conditions for the development of connective tissue at the site of injury. A promising material for biomedical applications is chitosan-a linear polysaccharide obtained by the deacetylation of chitin. It has been found to be nontoxic, biodegradable, biofunctional and biocompatible in addition to having antimicrobial characteristics. In this study we designed new chitin-chitosan substitutes for dura mater closure and evaluated their effectiveness and safety. Chitosan films were produced from 3 % of chitosan (molar mass-200, 500 or 700 kDa, deacetylation rate 80-90%) with addition of 20% of chitin. Antimicrobial effictively and cell viability were analysed for the different molar masses of chitosan. The film containing chitosan of molar mass 200 kDa, had the best antimicrobial and biological activity and was successfully used for experimental duraplasty in an in vivo model. In conclusion the chitin-chitosan membrane designed here met the requirements for a dura matter graft exhibiting the ability to support cell growth, inhibit microbial growth and biodegradade at an appropriate rate. Therefore this is a promising material for clinical duroplasty.

  10. Association of Guide RNA Binding Protein gBP21 with Active RNA Editing Complexes in Trypanosoma brucei

    PubMed Central

    Allen, Thomas E.; Heidmann, Stefan; Reed, RoseMary; Myler, Peter J.; Göringer, H. Ulrich; Stuart, Kenneth D.

    1998-01-01

    RNA editing in Trypanosoma brucei mitochondria produces mature mRNAs by a series of enzyme-catalyzed reactions that specifically insert or delete uridylates in association with a macromolecular complex. Using a mitochondrial fraction enriched for in vitro RNA editing activity, we produced several monoclonal antibodies that are specific for a 21-kDa guide RNA (gRNA) binding protein initially identified by UV cross-linking. Immunofluorescence studies localize the protein to the mitochondrion, with a preference for the kinetoplast. The antibodies cause a supershift of previously identified gRNA-specific ribonucleoprotein complexes and immunoprecipitate in vitro RNA editing activities that insert and delete uridylates. The immunoprecipitated material also contains gRNA-specific endoribonuclease, terminal uridylyltransferase, and RNA ligase activities as well as gRNA and both edited and unedited mRNA. The immunoprecipitate contains numerous proteins, of which the 21-kDa protein, a 90-kDa protein, and novel 55- and 16-kDa proteins can be UV cross-linked to gRNA. These studies indicate that the 21-kDa protein associates with the ribonucleoprotein complex (or complexes) that catalyze RNA editing. PMID:9742118

  11. Nuclear Forensic Inferences Using Iterative Multidimensional Statistics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robel, M; Kristo, M J; Heller, M A

    2009-06-09

    Nuclear forensics involves the analysis of interdicted nuclear material for specific material characteristics (referred to as 'signatures') that imply specific geographical locations, production processes, culprit intentions, etc. Predictive signatures rely on expert knowledge of physics, chemistry, and engineering to develop inferences from these material characteristics. Comparative signatures, on the other hand, rely on comparison of the material characteristics of the interdicted sample (the 'questioned sample' in FBI parlance) with those of a set of known samples. In the ideal case, the set of known samples would be a comprehensive nuclear forensics database, a database which does not currently exist. Inmore » fact, our ability to analyze interdicted samples and produce an extensive list of precise materials characteristics far exceeds our ability to interpret the results. Therefore, as we seek to develop the extensive databases necessary for nuclear forensics, we must also develop the methods necessary to produce the necessary inferences from comparison of our analytical results with these large, multidimensional sets of data. In the work reported here, we used a large, multidimensional dataset of results from quality control analyses of uranium ore concentrate (UOC, sometimes called 'yellowcake'). We have found that traditional multidimensional techniques, such as principal components analysis (PCA), are especially useful for understanding such datasets and drawing relevant conclusions. In particular, we have developed an iterative partial least squares-discriminant analysis (PLS-DA) procedure that has proven especially adept at identifying the production location of unknown UOC samples. By removing classes which fell far outside the initial decision boundary, and then rebuilding the PLS-DA model, we have consistently produced better and more definitive attributions than with a single pass classification approach. Performance of the iterative PLS-DA method compared favorably to that of classification and regression tree (CART) and k nearest neighbor (KNN) algorithms, with the best combination of accuracy and robustness, as tested by classifying samples measured independently in our laboratories against the vendor QC based reference set.« less

  12. Investigation on micro-patterned gold-plated polymer substrate for a micro hydraulic actuator

    NASA Astrophysics Data System (ADS)

    Sundaresan, Vishnu Baba; Akle, Barbar; Leo, Donald J.

    2006-03-01

    Plants have the ability to develop large mechanical force from chemical energy available with bio-fuels. The energy released by the cleavage of a terminal phosphate ion during the hydrolysis of a bio-fuel assists the transport of ions and fluids in cellular homeostasis. Materials that develop pressure and hence strain similar to the response of plants to an external stimuli are classified as nastic materials. This new class of actuators use protein transporters as functional units to move species and result in deformation [Leo et al 2005 (Proceedings of IMECE - 06)]. The ion transporters are hydrocarbons which are formed across the cellular membranes. The membranes that house the ion transporters are aggregates of phospholipids rigidized by cytoskeleton. Reconstituting these nano-machines on a harder matrix is quintessential to build a functional device. Artificial phospholipid membranes or Biliayer lipid membranes (BLM) have poor structural integrity and do not adhere to most surfaces. Patterned arrays of pores made on Poly-propylene glycol-diacrylate (PPG-DA) substrate, a photo curable polymer was made available to us for initial design iterations for an actuator. Hydrophobicity of PPG-DA posed initial problems to support a BLM. We modified the surface of micropatterned PPG-DA membrane by gold plating it. The surface of the porous PPG-DA membranes was plated with gold (Au). A 10nm seeding layer of Au was sputtered on the surface of the membrane. Further gold was reduced onto the sputtered gold surface [Supriya et al(Langmuir 2004, 20, 8870-8876)] by suspending the samples in a solution of hydroxylamine and Hydrogen tetrachloroaurate(III) trihydrate [HAuCl4.3H2O]. This reduction process increased the thickness of the gold, enhanced its adhesion to the PPG-DA substrate and improved the shapes of the pores. This surface modification of PPG-DA helped us form stable BLM with 1-Palmitoyl-2-Oleoyl-sn-Glycero-3- [Phospho-L-Serine] (Sodium Salt) (POPS), 1-Palmitoyl-2-Oleoyl-sn-Glycero- 3-Phosphoethanolamine (POPE) lipids. The observed ionic resistance of the BLM remained stable and sustained 4 mm water column for the the four hours observation period. This article describes the procedure we adopted to modify the PPG-DA substrate, form a BLM and the procedure to quantify the stability of the BLM formed with -amine and -thiol head groups in the lipids.

  13. Interference between Maintenance and Processing in Working Memory: The Effect of Item-Distractor Similarity in Complex Span

    ERIC Educational Resources Information Center

    Oberauer, Klaus; Farrell, Simon; Jarrold, Christopher; Pasiecznik, Kazimir; Greaves, Martin

    2012-01-01

    Four experiments examined the effect of phonological similarity between items and distractors on complex span performance. Item-distractor similarity benefited serial recall when distractors followed the items they were similar to, but not when distractors preceded the items they were similar to. These findings are predicted by C-SOB (contextual…

  14. Simultaneous determination of ascorbic acid, dopamine and uric acid based on tryptophan functionalized graphene.

    PubMed

    Lian, Qianwen; He, Zhifang; He, Qian; Luo, Ai; Yan, Kaiwang; Zhang, Dongxia; Lu, Xiaoquan; Zhou, Xibin

    2014-05-01

    A new type of tryptophan-functionalized graphene nanocomposite (Trp-GR) was synthesized by utilizing a facile ultrasonic method via π-π conjugate action between graphene (GR) and tryptophan (Trp) molecule. The material as prepared had well dispersivity in water and better conductivity than pure GR. The surface morphology of Trp-GR was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. The electrochemical behaviors of ascorbic acid (AA), dopamine (DA), and uric acid (UA) were investigated by cyclic voltammetry (CV) on the surface of Trp-GR. The separation of the oxidation peak potentials for AA-DA, DA-UA and UA-AA was about 182 mV, 125 mV and 307 mV, which allowed simultaneously determining AA, DA, and UA. Differential pulse voltammetery (DPV) was used for the determination of AA, DA, and UA in their mixture. Under optimum conditions, the linear response ranges for the determination of AA, DA, and UA were 0.2-12.9 mM, 0.5-110 μM, and 10-1000 μM, with the detection limits (S/N=3) of 10.09 μM, 0.29 μM and 1.24 μM, respectively. Furthermore, the modified electrode was investigated for real sample analysis. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  15. Using human sera to identify a 52-kDa exoantigen of Penicillium chrysogenum and implications of polyphasic taxonomy of anamorphic ascomycetes in the study of antigenic proteins.

    PubMed

    Wilson, Aaron M; Luo, Wen; Miller, J David

    2009-11-01

    We are interested in isolating and identifying antigenic fungal proteins from species that grow on damp building materials. The indoor clade of Penicillium chrysogenum, the so-called Fleming clade, is the most common species of Penicillium on moldy building materials. We have identified a 52-kDa marker protein for the indoor clade of P. chrysogenum not present in a taxonomically diverse selection of fungi. It is found in high concentrations in protein extracted from the fungus grown on paper-faced gypsum wallboard. During this process, we illuminated the variability in response to patient sera and of strains of the fungus collected over a wide geographic area. From a collection of sera from all over the USA, 25 of the 48 patients reacted to the 52-kDa protein from this prescreened collection of sera. Most strain/antibody combinations had proportionate ELISA response associated with the presence of the target. However, approximately 25% of the strain/patient serum combinations included people who responded to many common allergens from the Penicillia. All the P. chrysogenum strains tested produced the target protein. However, there was considerable variability in patient IgG response to 32-, 30-, and 18-kDa antigens and in their production by the various clade 4 strains. The target protein was not found in spores or culture extracts of a wide selection of relevant fungi. It appears that the previous studies have been conducted on strains of the fungus from the three clades not those associated with the built environment.

  16. An electrochemical sensor prepared by sonochemical one-pot synthesis of multi-walled carbon nanotube-supported cobalt nanoparticles for the simultaneous determination of paracetamol and dopamine.

    PubMed

    Kutluay, Aysegul; Aslanoglu, Mehmet

    2014-08-11

    Multi-walled carbon nanotubes (MWCNTs) functionalized by cobalt nanoparticles were obtained using a single step chemical deposition method in an ultrasonic bath. The composite material was characterized using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The electroactivity of the cobalt-functionalized MWCNTs was assessed in respect to the electrooxidation of paracetamol (PAR) and dopamine (DA). It was found that the carbon nanotube supported cobalt nanoparticles have significantly higher catalytic properties. The proposed electrode has been applied for the simultaneous determination of PAR and DA. The modified electrode could resolve the overlapped voltammetric waves of PAR and DA into two well-defined voltammetric peaks with peak to peak separation of about 203 mV. On the other hand, the presence of potential drug interfering compounds AA and UA did not affect the voltammetric responses of PAR and DA. The current of oxidation peaks showed a linear dependent on the concentrations of PAR and DA in the range of 5.2×10(-9)-4.5×10(-7) M (R(2)=0.9987) and 5.0×10(-8)-3.0×10(-6) M (R(2)=0.9999), respectively. The detection limits of 1.0×10(-9) M and 1.5×10(-8) M were obtained for PAR and DA, respectively. The proposed electrode showed good stability (peak current change: 4.9% with and RSD of 2.6% for PAR; 5.5% with and RSD of 3.0% for DA over 3 weeks), reproducibility (RSD 2.3% for PAR and RSD 1.5% for DA), repeatability (RSD 2.25% for PAR and RSD 2.50% for DA) and high recovery (99.7% with an RSD of 1.3% for PAR; 100.8% with an RSD of 1.8% for DA). The proposed method was successfully applied to the determination of PAR and DA in pharmaceuticals. Copyright © 2014. Published by Elsevier B.V.

  17. Super-hydrophobic Silver-Doped TiO2 @ Polycarbonate Coatings Created on Various Material Substrates with Visible-Light Photocatalysis for Self-Cleaning Contaminant Degradation

    PubMed Central

    Li, Zhengjian; Sun, Zongzhao; Duan, Zhiqiang; Li, Rui; Yang, Yanli; Wang, Jingyi; Lv, Xiaoxia; Qi, Wei; Wang, Hua

    2017-01-01

    In the present work, a facile and efficient fabrication method has been developed for creating super-hydrophobic coatings of silver-doped TiO2@polycarbonate (TiO2 (Ag)@PC) on the substrates of different materials with photocatalytic self-cleaning performances simply by the “dipping and drying” process. The substrates were first patterned with glue and then deposited with the dopamine-capped TiO2 (Ag)@PC (DA-TiO2 (Ag)@PC) nanocomposites, followed by the further etching with dimethylbenzene. The so prepared super-hydrophobic E-DA-TiO2(Ag)@PC coatings could present the lotus leaf-like porous architectures, high adhesion stability, and especially the visible-light photocatalysis for organic contaminant degradation, thus promising the wide outdoor and indoor applications like water proofing, metal erosion protection, and surface self-cleaning. PMID:28218285

  18. Super-hydrophobic Silver-Doped TiO2 @ Polycarbonate Coatings Created on Various Material Substrates with Visible-Light Photocatalysis for Self-Cleaning Contaminant Degradation.

    PubMed

    Li, Zhengjian; Sun, Zongzhao; Duan, Zhiqiang; Li, Rui; Yang, Yanli; Wang, Jingyi; Lv, Xiaoxia; Qi, Wei; Wang, Hua

    2017-02-20

    In the present work, a facile and efficient fabrication method has been developed for creating super-hydrophobic coatings of silver-doped TiO 2 @polycarbonate (TiO 2 (Ag)@PC) on the substrates of different materials with photocatalytic self-cleaning performances simply by the "dipping and drying" process. The substrates were first patterned with glue and then deposited with the dopamine-capped TiO 2 (Ag)@PC (DA-TiO 2 (Ag)@PC) nanocomposites, followed by the further etching with dimethylbenzene. The so prepared super-hydrophobic E-DA-TiO 2 (Ag)@PC coatings could present the lotus leaf-like porous architectures, high adhesion stability, and especially the visible-light photocatalysis for organic contaminant degradation, thus promising the wide outdoor and indoor applications like water proofing, metal erosion protection, and surface self-cleaning.

  19. Super-hydrophobic Silver-Doped TiO2 @ Polycarbonate Coatings Created on Various Material Substrates with Visible-Light Photocatalysis for Self-Cleaning Contaminant Degradation

    NASA Astrophysics Data System (ADS)

    Li, Zhengjian; Sun, Zongzhao; Duan, Zhiqiang; Li, Rui; Yang, Yanli; Wang, Jingyi; Lv, Xiaoxia; Qi, Wei; Wang, Hua

    2017-02-01

    In the present work, a facile and efficient fabrication method has been developed for creating super-hydrophobic coatings of silver-doped TiO2@polycarbonate (TiO2 (Ag)@PC) on the substrates of different materials with photocatalytic self-cleaning performances simply by the “dipping and drying” process. The substrates were first patterned with glue and then deposited with the dopamine-capped TiO2 (Ag)@PC (DA-TiO2 (Ag)@PC) nanocomposites, followed by the further etching with dimethylbenzene. The so prepared super-hydrophobic E-DA-TiO2(Ag)@PC coatings could present the lotus leaf-like porous architectures, high adhesion stability, and especially the visible-light photocatalysis for organic contaminant degradation, thus promising the wide outdoor and indoor applications like water proofing, metal erosion protection, and surface self-cleaning.

  20. Comparative study of corn stover pretreated by dilute acid and cellulose solvent-based lignocellulose fractionation: Enzymatic hydrolysis, supramolecular structure, and substrate accessibility.

    PubMed

    Zhu, Zhiguang; Sathitsuksanoh, Noppadon; Vinzant, Todd; Schell, Daniel J; McMillan, James D; Zhang, Y-H Percival

    2009-07-01

    Liberation of fermentable sugars from recalcitrant biomass is among the most costly steps for emerging cellulosic ethanol production. Here we compared two pretreatment methods (dilute acid, DA, and cellulose solvent and organic solvent lignocellulose fractionation, COSLIF) for corn stover. At a high cellulase loading [15 filter paper units (FPUs) or 12.3 mg cellulase per gram of glucan], glucan digestibilities of the corn stover pretreated by DA and COSLIF were 84% at hour 72 and 97% at hour 24, respectively. At a low cellulase loading (5 FPUs per gram of glucan), digestibility remained as high as 93% at hour 24 for the COSLIF-pretreated corn stover but reached only approximately 60% for the DA-pretreated biomass. Quantitative determinations of total substrate accessibility to cellulase (TSAC), cellulose accessibility to cellulase (CAC), and non-cellulose accessibility to cellulase (NCAC) based on adsorption of a non-hydrolytic recombinant protein TGC were measured for the first time. The COSLIF-pretreated corn stover had a CAC of 11.57 m(2)/g, nearly twice that of the DA-pretreated biomass (5.89 m(2)/g). These results, along with scanning electron microscopy images showing dramatic structural differences between the DA- and COSLIF-pretreated samples, suggest that COSLIF treatment disrupts microfibrillar structures within biomass while DA treatment mainly removes hemicellulose. Under the tested conditions COSLIF treatment breaks down lignocellulose structure more extensively than DA treatment, producing a more enzymatically reactive material with a higher CAC accompanied by faster hydrolysis rates and higher enzymatic digestibility. (c) 2009 Wiley Periodicals, Inc.

  1. The role of transparency in da Vinci stereopsis.

    PubMed

    Zannoli, Marina; Mamassian, Pascal

    2011-10-15

    The majority of natural scenes contains zones that are visible to one eye only. Past studies have shown that these monocular regions can be seen at a precise depth even though there are no binocular disparities that uniquely constrain their locations in depth. In the so-called da Vinci stereopsis configuration, the monocular region is a vertical line placed next to a binocular rectangular occluder. The opacity of the occluder has been mentioned to be a necessary condition to obtain da Vinci stereopsis. However, this opacity constraint has never been empirically tested. In the present study, we tested whether da Vinci stereopsis and perceptual transparency can interact using a classical da Vinci configuration in which the opacity of the occluder varied. We used two different monocular objects: a line and a disk. We found no effect of the opacity of the occluder on the perceived depth of the monocular object. A careful analysis of the distribution of perceived depth revealed that the monocular object was perceived at a depth that increased with the distance between the object and the occluder. The analysis of the skewness of the distributions was not consistent with a double fusion explanation, favoring an implication of occlusion geometry in da Vinci stereopsis. A simple model that includes the geometry of the scene could account for the results. In summary, the mechanism responsible to locate monocular regions in depth is not sensitive to the material properties of objects, suggesting that da Vinci stereopsis is solved at relatively early stages of disparity processing. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Lithographic microfabrication of biocompatible polymers for tissue engineering and lab-on-a-chip applications

    NASA Astrophysics Data System (ADS)

    Balciunas, Evaldas; Jonusauskas, Linas; Valuckas, Vytautas; Baltriukiene, Daiva; Bukelskiene, Virginija; Gadonas, Roaldas; Malinauskas, Mangirdas

    2012-06-01

    In this work, a combination of Direct Laser Writing (DLW), PoliDiMethylSiloxane (PDMS) soft lithography and UV lithography was used to create cm- scale microstructured polymer scaolds for cell culture experiments out of dierent biocompatible materials: novel hybrid organic-inorganic SZ2080, PDMS elastomer, biodegradable PEG- DA-258 and SU-8. Rabbit muscle-derived stem cells were seeded on the fabricated dierent periodicity scaolds to evaluate if the relief surface had any eect on cell proliferation. An array of microlenses was fabricated using DLW out of SZ2080 and replicated in PDMS and PEG-DA-258, showing good potential applicability of the used techniques in many other elds like micro- and nano- uidics, photonics, and MicroElectroMechanical Systems (MEMS). The synergetic employment of three dierent fabrication techniques allowed to produce desired objects with low cost, high throughput and precision as well as use materials that are dicult to process by other means (PDMS and PEG-DA-258). DLW is a relatively slow fabrication method, since the object has to be written point-by-point. By applying PDMS soft lithography, we were enabled to replicate laser-fabricated scaolds for stem cell growth and micro-optical elements for lab-on-a-chip applications with high speed, low cost and good reproducible quality.

  3. Evaluation of Delamination Onset and Growth Characterization Methods under Mode I Fatigue Loading

    NASA Technical Reports Server (NTRS)

    Murri, Gretchen B.

    2013-01-01

    Double-cantilevered beam specimens of IM7/8552 graphite/epoxy from two different manufacturers were tested in static and fatigue to compare the material characterization data and to evaluate a proposed ASTM standard for generating Paris Law equations for delamination growth. Static results were used to generate compliance calibration constants for reducing the fatigue data, and a delamination resistance curve, GIR, for each material. Specimens were tested in fatigue at different initial cyclic GImax levels to determine a delamination onset curve and the delamination growth rate. The delamination onset curve equations were similar for the two sources. Delamination growth rate was calculated by plotting da/dN versus GImax on a log-log scale and fitting a Paris Law. Two different data reduction methods were used to calculate da/dN. To determine the effects of fiber-bridging, growth results were normalized by the delamination resistance curves. Paris Law exponents decreased by 31% to 37% after normalizing the data. Visual data records from the fatigue tests were used to calculate individual compliance constants from the fatigue data. The resulting da/dN versus GImax plots showed improved repeatability for each source, compared to using averaged static data. The Paris Law expressions for the two sources showed the closest agreement using the individually fit compliance data.

  4. [Lectins from Sambucus nigra L inflorescences: isolation and investigation of biological activity using procaryotic test-systems].

    PubMed

    Karpova, I S; Korets'ka, N V; Pal'chykovs'ka, L H; Nehruts'ka, V V

    2007-01-01

    Isolation of lectins from extracts of the Sambucus nigra inflorescences and of pollen material have been performed using isoelectric focusing without carrier ampholytes (autofocusing). Fractions active in agglutination tests with different carbohydrate specificity were subjected to SDS-PAGE. The major lectin found in whole inflores-cences was GalNAc specific and is proposed to be a heterotetramer with subunits of about 30 and 33 kDa. It was called SNAflu-I. At least two other lectins were present in the pollen material and supposed to consist of identical subunits. Major positively charged lectin was Glc/Man specific with subunit of 26 kDa and called SNApol-I. Other pollen component (SNApol-II) was Gal specific with subunit of about 20 kDa. In order to elucidate cell targets sensitive for the S. nigra lectin's activity the combined effects of the lectins and transcriptional of phenazine origin on B. subtilis cells growth have been studied. Only SNApol-I demonstrated the antagonistic activity against these inhibitors in vivo. This lectin but not the SNAflu-I can also inhibit transcription in vitro. It is supposed that lectins from the same source may act in different directions on cell metabolism. Particularly one of the common targets may be the DNA-dependent synthesis of RNA.

  5. Die attach dimension and material on thermal conductivity study for high power COB LED

    NASA Astrophysics Data System (ADS)

    Sarukunaselan, K.; Ong, N. R.; Sauli, Z.; Mahmed, N.; Kirtsaeng, S.; Sakuntasathien, S.; Suppiah, S.; Alcain, J. B.; Retnasamy, V.

    2017-09-01

    High power LED began to gain popularity in the semiconductor market due to its efficiency and luminance. Nonetheless, along with the increased in efficiency, there was an increased in the junction temperature too. The alleviating junction temperature is undesirable since the performances and lifetime will be degraded over time. Therefore, it is crucial to solve this thermal problem by maximizing the heat dissipation to the ambience. Improvising the die attach (DA) layer would be the best option because this layer is sandwiched between the chip (heat source) and the substrate (channel to the ambient). In this paper, the impact of thickness and thermal conductivity onto the junction temperature and Von Mises stress is analyzed. Results obtained showed that the junction temperature is directly proportional to the thickness but the stress was inversely proportional to the thickness of the DA. The thermal conductivity of the materials did affect the junction temperature as there was not much changes once the thermal conductivity reached 20W/mK. However, no significant changes were observed on the Von Mises stress caused by the thermal conductivity. Material with the second highest thermal conductivity had the lowest stress, whereas the highest conductivity material had the highest stress value at 20 µm. Overall, silver sinter provided the best thermal dissipation compared to the other materials.

  6. Monoclonal antibody against a serotype antigen of Porphyromonas (Bacteroides) endodontalis and characteristics of the antigen.

    PubMed Central

    Hanazawa, S; Sagiya, T; Amano, S; Nishikawa, H; Kitano, S

    1990-01-01

    Recent studies have demonstrated the presence of three serotypes (O1K1, O1K2, and O1K-) of Porphyromonas (Bacteroides) endodontalis. In the present study, a hybridoma cell line producing monoclonal antibody (BEE11) specific for serotype O1K1 of P. endodontalis was established. The specificity of the antibody was evaluated by enzyme-linked immunosorbent assay and immunoslot blot analysis. BEE11 antibody reacted with strains ATCC 35406, HG 400, and HG 421 of the bacterium. However, it did not react with HG 422 or HG 948. Also, the antibody did not react with any of the black-pigmented Bacteroides strains tested. Although the antibody reacted with total cell envelope and capsule materials, it did not do so with lipopolysaccharide. The antibody reacted with antigen material having a molecular mass of 110 kilodaltons (kDa), as judged from fractionation by Superose 12 prep gel chromatography. When the peak fraction from the Superose 12 column was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) analysis, the reactivity was detected as a single band at an apparent molecular mass of about 52 kDa. The antigen material purified partially by high-performance liquid chromatography was sensitive to trypsin, V8 protease, and heating to 80 degrees C but not to neuraminidase. Therefore, the present study shows that BEE11 antibody recognizes a serotype antigen of P. endodontalis which may be a dimer consisting of monomers having molecular masses of approximately 52 kDa and sensitivity to proteases and heat. Images PMID:2370106

  7. Lessons and Impressions of the Czech Capital Markets

    DTIC Science & Technology

    2012-02-13

    violently broke up a peaceful pro- democracy demonstration and brutally beat many student participants. In the days that followed, political groups ...united to become the Civic Forum, an umbrella group championing bureaucratic reform and civil liberties. Faced with an overwhelming popular...banks. Belgian KBC Bank acquired ČSOB in 1999 and Erste Group , a leading Austrian financial institution, acquired Ceska Sporitelna in 2000

  8. Shortness of breath in clinical practice: A case for left atrial function and exercise stress testing for a comprehensive diastolic heart failure workup

    PubMed Central

    Iyngkaran, Pupalan; Anavekar, Nagesh S; Neil, Christopher; Thomas, Liza; Hare, David L

    2017-01-01

    The symptom cluster of shortness of breath (SOB) contributes significantly to the outpatient workload of cardiology services. The workup of these patients includes blood chemistry and biomarkers, imaging and functional testing of the heart and lungs. A diagnosis of diastolic heart failure is inferred through the exclusion of systolic abnormalities, a normal pulmonary function test and normal hemoglobin, coupled with diastolic abnormalities on echocardiography. Differentiating confounders such as obesity or deconditioning in a patient with diastolic abnormalities is difficult. While the most recent guidelines provide more avenues for diagnosis, such as incorporating the left atrial size, little emphasis is given to understanding left atrial function, which contributes to at least 25% of diastolic left ventricular filling; additionally, exercise stress testing to elicit symptoms and test the dynamics of diastolic parameters, especially when access to the “gold standard” invasive tests is lacking, presents clinical translational gaps. It is thus important in diastolic heart failure work up to understand left atrial mechanics and the role of exercise testing to build a comprehensive argument for the diagnosis of diastolic heart failure in a patient presenting with SOB. PMID:29354484

  9. Working memory still needs verbal rehearsal.

    PubMed

    Lucidi, Annalisa; Langerock, Naomi; Hoareau, Violette; Lemaire, Benoît; Camos, Valérie; Barrouillet, Pierre

    2016-02-01

    The causal role of verbal rehearsal in working memory has recently been called into question. For example, the SOB-CS (Serial Order in a Box-Complex Span) model assumes that there is no maintenance process for the strengthening of items in working memory, but instead a process of removal of distractors that are involuntarily encoded and create interference with memory items. In the present study, we tested the idea that verbal working memory performance can be accounted for without assuming a causal role of the verbal rehearsal process. We demonstrate in two experiments using a complex span task and a Brown-Peterson paradigm that increasing the number of repetitions of the same distractor (the syllable ba that was read aloud at each of its occurrences on screen) has a detrimental effect on the concurrent maintenance of consonants whereas the maintenance of spatial locations remains unaffected. A detailed analysis of the tasks demonstrates that accounting for this effect within the SOB-CS model requires a series of unwarranted assumptions leading to undesirable further predictions contradicted by available experimental evidence. We argue that the hypothesis of a maintenance mechanism based on verbal rehearsal that is impeded by concurrent articulation still provides the simplest and most compelling account of our results.

  10. Elimination of sulphur odours at landfills by bioconversion and the corona discharge plasma technique.

    PubMed

    Xia, Fangfang; Liu, Xin; Kang, Ying; He, Ruo; Wu, Zucheng

    2015-01-01

    Hydrogen sulphide (H2S) contributes a lot to odours at landfills, which is a threat to the environment and the health of the staff therein. To mitigate its emission, the bioconversion within landfill cover soils (LCSs) was introduced. H2S emission and concentration both in the field air above the landfill and in microcosm testing were surveyed. Results indicated that H2S emission and concentration in the landfill varied with landfill seasons and sites. There existed relationship between H2S concentration and fluxes spatially and temporally. To characterize and assess the spatial and temporal diversity of sulphur-oxidizing bacteria (SOB) and sulphate-reducing bacteria (SRB) in the LCSs, the terminal-restriction fragment length polymorphism technique was employed. Using the functional genes of dsrB and soxB, SOB, including Halothiobacillus, Rhodothalassium, Paracocccus, Allochromatium, and Thiobacillus, and SRB, including Desulfovibrio, Syntrophobacter, Desulfomonile and Desulfobacca, were identical and exhibited the dominant role in the LCSs. By employing an alternative available corona reactor, more than 90% removal efficiencies of sulphides were demonstrated, suggesting that the LCSs for eliminating odours in a lower concentration would be feasible.

  11. One-Pot Green Synthesis of Graphene Nanosheets Encapsulated Gold Nanoparticles for Sensitive and Selective Detection of Dopamine

    PubMed Central

    Thirumalraj, Balamurugan; Rajkumar, Chellakannu; Chen, Shen-Ming; Palanisamy, Selvakumar

    2017-01-01

    We report a simple new approach for green preparation of gallic acid supported reduced graphene oxide encapsulated gold nanoparticles (GA-RGO/AuNPs) via one-pot hydrothermal method. The as-prepared composites were successfully characterized by using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray powder diffraction techniques (XRD), scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM) and elemental analysis. The GA-RGO/AuNPs modified electrode behaves as a hybrid electrode material for sensitive and selective detection of dopamine (DA) in presence of ascorbic acid (AA) and uric acid (UA). The GA-RGO/AuNPs modified electrode displays an excellent electrocatalytic activity towards the oxidation of DA and exhibits a wide linear response range over the DA concentrations from 0.01–100.3 μM with a detection limit (LOD) of 2.6 nM based on S/N = 3. In addition, the proposed sensor could be applied for the determination of DA in human serum and urine samples for practical analysis. PMID:28128225

  12. One-Pot Green Synthesis of Graphene Nanosheets Encapsulated Gold Nanoparticles for Sensitive and Selective Detection of Dopamine

    NASA Astrophysics Data System (ADS)

    Thirumalraj, Balamurugan; Rajkumar, Chellakannu; Chen, Shen-Ming; Palanisamy, Selvakumar

    2017-01-01

    We report a simple new approach for green preparation of gallic acid supported reduced graphene oxide encapsulated gold nanoparticles (GA-RGO/AuNPs) via one-pot hydrothermal method. The as-prepared composites were successfully characterized by using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray powder diffraction techniques (XRD), scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM) and elemental analysis. The GA-RGO/AuNPs modified electrode behaves as a hybrid electrode material for sensitive and selective detection of dopamine (DA) in presence of ascorbic acid (AA) and uric acid (UA). The GA-RGO/AuNPs modified electrode displays an excellent electrocatalytic activity towards the oxidation of DA and exhibits a wide linear response range over the DA concentrations from 0.01-100.3 μM with a detection limit (LOD) of 2.6 nM based on S/N = 3. In addition, the proposed sensor could be applied for the determination of DA in human serum and urine samples for practical analysis.

  13. Gel Permeation Chromatography Characterization of the Chain Length Distributions in Thiol-Acrylate Photopolymer Networks

    PubMed Central

    Rydholm, Amber E.; Held, Nicole L.; Bowman, Christopher N.; Anseth, Kristi S.

    2008-01-01

    Crosslinked, degradable networks formed from the photopolymerization of thiol and acrylate monomers are explored as potential biomaterials. The degradation behavior and material properties of these networks are influenced by the molecular weight of the nondegradable thiol-polyacrylate backbone chains that form during photopolymerization. Here, gel permeation chromatography was used to characterize the thiol-polyacrylate backbone chain lengths in degraded thiol-acrylate networks. Increasing thiol functionality from 1 to 4 increased the backbone molecular weight (M̄w = 2.3 ± 0.07 × 104 Da for monothiol and 3.6 ± 0.1 × 104 Da for tetrathiol networks). Decreasing thiol functional group concentration from 30 to 10 mol% also increased the backbone lengths (M̄w = 7.3 ± 1.1 × 104 Da for the networks containing 10 mol% thiol groups as compared to 3.6 ± 0.1 × 104 Da for 30 mol% thiol). Finally, the backbone chain lengths were probed at various stages of degradation and an increase in backbone molecular weight was observed as mass loss progressed from 10 to 70%. PMID:19079733

  14. Characterization of cellulolytic enzymes and bioH2 production from anaerobic thermophilic Clostridium sp. TCW1.

    PubMed

    Lo, Yung-Chung; Huang, Chi-Yu; Cheng, Chieh-Lun; Lin, Chiu-Yue; Chang, Jo-Shu

    2011-09-01

    A thermophilic anaerobic bacterium Clostridium sp. TCW1 was isolated from dairy cow dung and was used to produce hydrogen from cellulosic feedstock. Extracellular cellulolytic enzymes produced from TCW1 strain were identified as endoglucanases (45, 53 and 70 kDa), exoglucanase (70 kDa), xylanases (53 and 60 kDa), and β-glucosidase (45 kDa). The endoglucanase and xylanase were more abundant. The optimal conditions for H2 production and enzyme production of the TCW1 strain were the same (60 °C, initial pH 7, agitation rate of 200 rpm). Ten cellulosic feedstock, including pure or natural cellulosic materials, were used as feedstock for hydrogen production by Clostridium strain TCW1 under optimal culture conditions. Using filter paper at 5.0 g/L resulted in the most effective hydrogen production performance, achieving a H2 production rate and yield of 57.7 ml/h/L and 2.03 mol H2/mol hexose, respectively. Production of cellulolytic enzyme activities was positively correlated with the efficiency of dark-H2 fermentation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Three-Dimensional Dynamic Loading of Sand

    DTIC Science & Technology

    2011-02-01

    strength yield strength of 40 MPa. In addition the inclusion of grain-on-grain stiction (friction) plays a major role in the compaction of sand at low...strains Figure 5 Stress-strain behavior for various grain and strength configurations When compared to experimental stre ss-strain data, both...of Materials, DYMAT 2009 Brussels Belgium, pg 1545–1551 [xi] Crawford, D.A. 2005. Using mesoscale modeling to investigate the role of material

  16. Melanin and Melanin-Related Polymers as Materials with Biomedical and Biotechnological Applications—Cuttlefish Ink and Mussel Foot Proteins as Inspired Biomolecules

    PubMed Central

    2017-01-01

    The huge development of bioengineering during the last years has boosted the search for new bioinspired materials, with tunable chemical, mechanical, and optoelectronic properties for the design of semiconductors, batteries, biosensors, imaging and therapy probes, adhesive hydrogels, tissue restoration, photoprotectors, etc. These new materials should complement or replace metallic or organic polymers that cause cytotoxicity and some adverse health effects. One of the most interesting biomaterials is melanin and synthetic melanin-related molecules. Melanin has a controversial molecular structure, dependent on the conditions of polymerization, and therefore tunable. It is found in animal hair and skin, although one of the common sources is cuttlefish (Sepia officinalis) ink. On the other hand, mussels synthesize adhesive proteins to anchor these marine animals to wet surfaces. Both melanin and mussel foot proteins contain a high number of catecholic residues, and their properties are related to these groups. Dopamine (DA) can easily polymerize to get polydopamine melanin (PDAM), that somehow shares properties with melanin and mussel proteins. Furthermore, PDAM can easily be conjugated with other components. This review accounts for the main aspects of melanin, as well as DA-based melanin-like materials, related to their biomedical and biotechnological applications. PMID:28718807

  17. LIBS data analysis using a predictor-corrector based digital signal processor algorithm

    NASA Astrophysics Data System (ADS)

    Sanders, Alex; Griffin, Steven T.; Robinson, Aaron

    2012-06-01

    There are many accepted sensor technologies for generating spectra for material classification. Once the spectra are generated, communication bandwidth limitations favor local material classification with its attendant reduction in data transfer rates and power consumption. Transferring sensor technologies such as Cavity Ring-Down Spectroscopy (CRDS) and Laser Induced Breakdown Spectroscopy (LIBS) require effective material classifiers. A result of recent efforts has been emphasis on Partial Least Squares - Discriminant Analysis (PLS-DA) and Principle Component Analysis (PCA). Implementation of these via general purpose computers is difficult in small portable sensor configurations. This paper addresses the creation of a low mass, low power, robust hardware spectra classifier for a limited set of predetermined materials in an atmospheric matrix. Crucial to this is the incorporation of PCA or PLS-DA classifiers into a predictor-corrector style implementation. The system configuration guarantees rapid convergence. Software running on multi-core Digital Signal Processor (DSPs) simulates a stream-lined plasma physics model estimator, reducing Analog-to-Digital (ADC) power requirements. This paper presents the results of a predictorcorrector model implemented on a low power multi-core DSP to perform substance classification. This configuration emphasizes the hardware system and software design via a predictor corrector model that simultaneously decreases the sample rate while performing the classification.

  18. Melanin and Melanin-Related Polymers as Materials with Biomedical and Biotechnological Applications-Cuttlefish Ink and Mussel Foot Proteins as Inspired Biomolecules.

    PubMed

    Solano, Francisco

    2017-07-18

    The huge development of bioengineering during the last years has boosted the search for new bioinspired materials, with tunable chemical, mechanical, and optoelectronic properties for the design of semiconductors, batteries, biosensors, imaging and therapy probes, adhesive hydrogels, tissue restoration, photoprotectors, etc. These new materials should complement or replace metallic or organic polymers that cause cytotoxicity and some adverse health effects. One of the most interesting biomaterials is melanin and synthetic melanin-related molecules. Melanin has a controversial molecular structure, dependent on the conditions of polymerization, and therefore tunable. It is found in animal hair and skin, although one of the common sources is cuttlefish (Sepia officinalis) ink. On the other hand, mussels synthesize adhesive proteins to anchor these marine animals to wet surfaces. Both melanin and mussel foot proteins contain a high number of catecholic residues, and their properties are related to these groups. Dopamine (DA) can easily polymerize to get polydopamine melanin (PDAM), that somehow shares properties with melanin and mussel proteins. Furthermore, PDAM can easily be conjugated with other components. This review accounts for the main aspects of melanin, as well as DA-based melanin-like materials, related to their biomedical and biotechnological applications.

  19. The Exploration of Peptide Biomarkers in Malignant Pleural Effusion of Lung Cancer Using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry

    PubMed Central

    Xu, Jing; Xu, Bin; Tang, Chuanhao; Li, Xiaoyan; Qin, Haifeng; Wang, Weixia; Wang, Hong; Wang, Zhongyuan; Li, Liangliang; Li, Zhihua; Gao, Hongjun

    2017-01-01

    Background. Diagnoses of malignant pleural effusion (MPE) are a crucial problem in clinics. In our study, we compared the peptide profiles of MPE and tuberculosis pleural effusion (TPE) to investigate the value of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) in diagnosis of MPE. Material and Methods. The 46 MPE and 32 TPE were randomly assigned to training set and validation set. Peptides were isolated by weak cation exchange magnetic beads and peaks in the m/z range of 800–10000 Da were analyzed. Comparing the peptide profile between 30 MPE and 22 TPE samples in training set by ClinProTools software, we screened the specific biomarkers and established a MALDI-TOF-MS classification of MPE. Finally, the other 16 MPE and 10 TPE were included to verify the model. We additionally determined carcinoembryonic antigen (CEA) in MPE and TPE samples using electrochemiluminescent immunoassay method. Results. Five peptide peaks (917.37 Da, 4469.39 Da, 1466.5 Da, 4585.21 Da, and 3216.87 Da) were selected to separate MPE and TPE by MALDI-TOF-MS. The sensitivity, specificity, and accuracy of the classification were 93.75%, 100%, and 96.15%, respectively, after blinded test. The sensitivity of CEA was significantly lower than MALDI-TOF-MS classification (P = 0.035). Conclusions. The results indicate MALDI-TOF-MS is a potential method for diagnosing MPE. PMID:28386154

  20. The Exploration of Peptide Biomarkers in Malignant Pleural Effusion of Lung Cancer Using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry.

    PubMed

    Xu, Jing; Xu, Bin; Tang, Chuanhao; Li, Xiaoyan; Qin, Haifeng; Wang, Weixia; Wang, Hong; Wang, Zhongyuan; Li, Liangliang; Li, Zhihua; Gao, Hongjun; He, Kun; Liu, Xiaoqing

    2017-01-01

    Background . Diagnoses of malignant pleural effusion (MPE) are a crucial problem in clinics. In our study, we compared the peptide profiles of MPE and tuberculosis pleural effusion (TPE) to investigate the value of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) in diagnosis of MPE. Material and Methods . The 46 MPE and 32 TPE were randomly assigned to training set and validation set. Peptides were isolated by weak cation exchange magnetic beads and peaks in the m / z range of 800-10000 Da were analyzed. Comparing the peptide profile between 30 MPE and 22 TPE samples in training set by ClinProTools software, we screened the specific biomarkers and established a MALDI-TOF-MS classification of MPE. Finally, the other 16 MPE and 10 TPE were included to verify the model. We additionally determined carcinoembryonic antigen (CEA) in MPE and TPE samples using electrochemiluminescent immunoassay method. Results . Five peptide peaks (917.37 Da, 4469.39 Da, 1466.5 Da, 4585.21 Da, and 3216.87 Da) were selected to separate MPE and TPE by MALDI-TOF-MS. The sensitivity, specificity, and accuracy of the classification were 93.75%, 100%, and 96.15%, respectively, after blinded test. The sensitivity of CEA was significantly lower than MALDI-TOF-MS classification ( P = 0.035). Conclusions . The results indicate MALDI-TOF-MS is a potential method for diagnosing MPE.

  1. Three-dimensional graphene-like carbon frameworks as a new electrode material for electrochemical determination of small biomolecules.

    PubMed

    Deng, Wenfang; Yuan, Xiaoyan; Tan, Yueming; Ma, Ming; Xie, Qingji

    2016-11-15

    Three-dimensional (3D) graphene-like carbon frameworks (3DGLCFs) were facilely prepared via copyrolysis of polyaniline and nickel nitrate powder, followed by acid etching. The as-prepared 3DGLCFs possess graphene-like network structure, high specific surface area, and high content nitrogen dopant. Because these features enable large electrochemically active surface area, rapid electron transfer, and fast transport of analytes to electrode surface, the 3DGLCFs modified glassy carbon electrode (GCE) shows current response much higher than commercial graphene (CG) modified GCE towards the oxidation of ascorbic acid (AA), dopamine (DA) and uric acid (UA). The anodic peak separations at 3DGLCFs/GCE are 0.23V between AA and DA, 0.13V between DA and UA, and 0.36V between AA and UA. For the simultaneous electrochemical determination of AA, DA and UA using differential pulse voltammetry, the 3DGLCFs/GCE shows linear response ranges of 1.25×10(-5)-4×10(-4)M for AA, 5×10(-8)-1.0×10(-5)M for DA, and 5×10(-8)-1.5×10(-5)M for UA, with low detection limits of 2×10(-6)M for AA, 1×10(-8)M for DA, and 1×10(-8)M for UA. The 3DGLCFs/GCE was also applied for the measurement of human serum, exhibiting satisfactory recoveries. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Development of Patients' Decision Aid for Older Women With Stage I Breast Cancer Considering Radiotherapy After Lumpectomy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wong, Jennifer; D'Alimonte, Laura; Angus, Jan

    Purpose: To develop a patient decision aid (PtDA) for older women with Stage I, pathologically node negative, estrogen receptor-positive progesterone receptor-positive breast cancer who are considering adjuvant radiotherapy after lumpectomy and to examine its impact on patients' decision making. Methods and Materials: A PtDA was developed and evaluated in three steps according to the Ottawa Decision Support Framework: (1) needs assessment (n = 16); (2) Pilot I to examine PtDA acceptability (n = 12); and (3) Pilot II, a pretest posttest (n = 38) with older women with estrogen receptor-positive progesterone receptor-positive breast cancer after lumpectomy who were receiving adjuvantmore » radiation therapy. Measures included patients' satisfaction with the PtDA, self-reported decisional conflict, level of distress, treatment-related knowledge, and choice predisposition. Results: The PtDA is a booklet that details each adjuvant treatment option's benefits, risks, and side effects tailored to the patient's clinical profile; includes a values clarification exercise; and includes steps to guide patients towards their decision. On the basis of qualitative comments and satisfaction ratings, all women thought that the PtDA was helpful and informative. In comparison with their baseline scores, patients had a statistically significant (p < 0.05) reduction in decisional conflict (adjusted mean difference [AMD], -7.18; 95% confidence interval [CI], -13.50 to 12.59); increased clarity of the benefits and risks (AMD, -10.86; CI, -20.33 to 21.49); and improved general treatment knowledge (AMD, 8.99; CI, 2.88-10.28) after using the PtDA. General trends were also reported in the patients' choice predisposition scores that suggested potential differences in treatment decision after PtDA use. Conclusions: This study provides evidence that this PtDA may be a helpful educational tool for this group of women. The quality of care for older breast cancer patients may be enhanced by the use of a tailored PtDA to help patients be better informed about their treatment options.« less

  3. Prevention of Oxidized Low Density Lipoprotein-Induced Endothelial Cell Injury by DA-PLGA-PEG-cRGD Nanoparticles Combined with Ultrasound

    PubMed Central

    Li, Zhaojun; Huang, Hui; Huang, Lili; Du, Lianfang; Sun, Ying; Duan, Yourong

    2017-01-01

    In general, atherosclerosis is considered to be a form of chronic inflammation. Dexamethasone has anti-inflammatory effects in atherosclerosis, but it was not considered for long-term administration on account of a poor pharmacokinetic profile and adverse side effects. Nanoparticles in which drugs can be dissolved, encapsulated, entrapped or chemically attached to the particle surface have abilities to incorporate dexamethasone and to be used as controlled or targeted drug delivery system. Long circulatory polymeric nanoparticles present as an assisting approach for controlled and targeted release of the encapsulated drug at the atherosclerotic site. Polymeric nanoparticles combined with ultrasound (US) are widely applied in cancer treatment due to their time applications, low cost, simplicity, and safety. However, there are few studies on atherosclerosis treatment using polymeric nanoparticles combined with US. In this study, targeted dexamethasone acetate (DA)-loaded poly (lactide-glycolide)-polyethylene glycol-cRGD (PLGA-PEG-cRGD) nanoparticles (DA-PLGA-PEG-cRGD NPs) were prepared by the emulsion-evaporation method using cRGD modified PLGA-PEG polymeric materials (PLGA-PEG-cRGD) prepared as the carrier. The average particle size of DA-PLGA-PEG-cRGD NPs was 221.6 ± 0.9 nm. Morphology of the nanoparticles was spherical and uniformly dispersed. In addition, the DA released profiles suggested that ultrasound could promote drug release from the nanocarriers and accelerate the rate of release. In vitro, the cellular uptake process of fluorescein isothiocyanate (FITC)@DA-PLGA-PEG-cRGD NPs combined with US into the damaged human umbilical vein endothelial cells (HUVECs) indicated that US promoted rapid intracellular uptake of FITC@DA- PLGA-PEG-cRGD NPs. The cell viability of DA-PLGA-PEG-cRGD NPs combined with US reached 91.9% ± 0.2%, which demonstrated that DA-PLGA-PEG-cRGD NPs combined with US had a positive therapeutic effect on damaged HUVECs. Overall, DA-PLGA-PEG-cRGD NPs in combination with US may provide a promising drug delivery system to enhance the therapeutic effects of these chemotherapeutics at the cellular level. PMID:28406431

  4. Prevention of Oxidized Low Density Lipoprotein-Induced Endothelial Cell Injury by DA-PLGA-PEG-cRGD Nanoparticles Combined with Ultrasound.

    PubMed

    Li, Zhaojun; Huang, Hui; Huang, Lili; Du, Lianfang; Sun, Ying; Duan, Yourong

    2017-04-13

    In general, atherosclerosis is considered to be a form of chronic inflammation. Dexamethasone has anti-inflammatory effects in atherosclerosis, but it was not considered for long-term administration on account of a poor pharmacokinetic profile and adverse side effects. Nanoparticles in which drugs can be dissolved, encapsulated, entrapped or chemically attached to the particle surface have abilities to incorporate dexamethasone and to be used as controlled or targeted drug delivery system. Long circulatory polymeric nanoparticles present as an assisting approach for controlled and targeted release of the encapsulated drug at the atherosclerotic site. Polymeric nanoparticles combined with ultrasound (US) are widely applied in cancer treatment due to their time applications, low cost, simplicity, and safety. However, there are few studies on atherosclerosis treatment using polymeric nanoparticles combined with US. In this study, targeted dexamethasone acetate (DA)-loaded poly (lactide-glycolide)-polyethylene glycol-cRGD (PLGA-PEG-cRGD) nanoparticles (DA-PLGA-PEG-cRGD NPs) were prepared by the emulsion-evaporation method using cRGD modified PLGA-PEG polymeric materials (PLGA-PEG-cRGD) prepared as the carrier. The average particle size of DA-PLGA-PEG-cRGD NPs was 221.6 ± 0.9 nm. Morphology of the nanoparticles was spherical and uniformly dispersed. In addition, the DA released profiles suggested that ultrasound could promote drug release from the nanocarriers and accelerate the rate of release. In vitro, the cellular uptake process of fluorescein isothiocyanate (FITC)@DA-PLGA-PEG-cRGD NPs combined with US into the damaged human umbilical vein endothelial cells (HUVECs) indicated that US promoted rapid intracellular uptake of FITC@DA- PLGA-PEG-cRGD NPs. The cell viability of DA-PLGA-PEG-cRGD NPs combined with US reached 91.9% ± 0.2%, which demonstrated that DA-PLGA-PEG-cRGD NPs combined with US had a positive therapeutic effect on damaged HUVECs. Overall, DA-PLGA-PEG-cRGD NPs in combination with US may provide a promising drug delivery system to enhance the therapeutic effects of these chemotherapeutics at the cellular level.

  5. Uranium Enrichment Safeguards

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Demuth, Scott F.; Trahan, Alexis Chanel

    2017-06-26

    DIV of facility layout, material flows, and other information provided in the DIQ. Material accountancy through an annual PIV and a number of interim inventory verifications, including UF6 cylinder identification and counting, NDA of cylinders, and DA on a sample collection of UF6. Application of C/S technologies utilizing seals and tamper-indicating devices (TIDs) on cylinders, containers, storage rooms, and IAEA instrumentation to provide continuity of knowledge between inspection. Verification of the absence of undeclared material and operations, especially HEU production, through SNRIs, LFUA of cascade halls, and environmental swipe sampling

  6. Effects of a Single Bout of Resistance Exercise in Different Volumes on Endothelium Adaptations in Healthy Animals.

    PubMed

    Mota, Marcelo Mendonça; Silva, Tharciano Luiz Teixeira Braga da; Macedo, Fabricio Nunes; Mesquita, Thássio Ricardo Ribeiro; Quintans, Lucindo José; Santana-Filho, Valter Joviniano de; Lauton-Santos, Sandra; Santos, Márcio Roberto Viana

    2017-05-01

    Resistance exercise (RE) has been recommended for patients with cardiovascular diseases. Recently, a few studies have demonstrated that the intensity of a single bout of RE has an effect on endothelial adaptations to exercise. However, there is no data about the effects of different volumes of RE on endothelium function. The aim of the study was to evaluate the effects of different volumes of RE in a single bout on endothelium-dependent vasodilatation and nitric oxide (NO) synthesis in the mesenteric artery of healthy animals. Male Wistar rats were divided into three groups: Control (Ct); low-volume RE (LV, 5 sets x 10 repetitions) and high-volume RE (HV, 15 sets x 10 repetitions). The established intensity was 70% of the maximal repetition test. After the exercise protocol, rings of mesenteric artery were used for assessment of vascular reactivity, and other mesenteric arteries were prepared for detection of measure NO production by DAF-FM fluorescence. Insulin responsiveness on NO synthesis was evaluated by stimulating the vascular rings with insulin (10 nM). The maximal relaxation response to insulin increased in the HV group only as compared with the Ct group. Moreover, the inhibition of nitric oxide synthesis (L-NAME) completely abolished the insulin-induced vasorelaxation in exercised rats. NO production showed a volume-dependent increase in the endothelial and smooth muscle layer. In endothelial layer, only Ct and LV groups showed a significant increase in NO synthesis when compared to their respective group under basal condition. On the other hand, in smooth muscle layer, NO fluorescence increased in all groups when compared to their respective group under basal condition. Our results suggest that a single bout of RE promotes vascular endothelium changes in a volume-dependent manner. The 15 sets x 10 repetitions exercise plan induced the greatest levels of NO synthesis. O exercício resistido (ER) tem sido recomendado para pacientes com doenças cardiovasculares. Recentemente, alguns estudos demonstraram que a intensidade de uma sessão de ER exerce um efeito sobre a disfunção endotelial. No entanto, não há dados sobre os efeitos de diferentes volumes de ER sobre a função endotelial. O objetivo deste estudo foi avaliar os efeitos de diferentes volumes de ER, realizados em uma única sessão, sobre a vasodilatação dependente do endotélio e síntese de óxido nítrico (NO) em artéria mesentérica de animais saudáveis. Ratos Wistar machos foram divididos em três grupos: Controle (Ct); baixo volume (BV, 5 séries x 10 repetições) e alto volume de ER (AV, 15 séries x 10 repetições). Foi estabelecida a intensidade de 70% do teste de repetição máxima. Após o protocolo de exercício, anéis de artéria mesentérica foram utilizados na avaliação da reatividade vascular, e outras artérias mesentéricas foram preparadas para a detecção da produção de NO por fluorescência com para do DAF-FM. A resposta à insulina pela síntese de NO foi avaliada estimulando-se os anéis vasculares com insulina (10nM). A resposta máxima do relaxamento induzido por insulina foi aumentada somente no grupo AV em comparação ao grupo Ct. Além disso, a inibição da síntese do NO (L-NAME), aboliu completamente o relaxamento vascular induzido por insulina em ratos exercitados. A produção de NO mostrou um aumento dependente do volume no endotélio e no músculo liso. No endotélio, apenas os grupos Ct e BV mostraram aumento significativo na síntese de NO quando comparado aos seus respectivos grupos sob condição basal. No entanto, no músculo liso, a fluorescência foi aumentada em todos os grupos quando comparados aos seus respectivos grupos sob a condição basal. Nossos resultados sugerem que uma única sessão de ER foi capaz de promover adaptações no endotélio vascular. Além disso, nós observamos que este efeito é volume-dependente e o volume de 15 séries x10 repetições induziu o maior aumento na síntese de NO.

  7. Intra-accumbens injections of the adenosine A2A agonist CGS 21680 affect effort-related choice behavior in rats

    PubMed Central

    Font, Laura; Mingote, Susana; Farrar, Andrew M.; Pereira, Mariana; Worden, Lila; Stopper, Colin; Port, Russell G.

    2009-01-01

    Rationale Nucleus accumbens dopamine (DA) participates in the modulation of instrumental behavior, including aspects of behavioral activation and effort-related choice behavior. Rats with impaired accumbens DA transmission reallocate their behavior away from food-reinforced activities that have high response requirements and instead select less-effortful types of food-seeking behavior. Although accumbens DA is considered a critical component of the brain circuitry regulating effort-related processes, emerging evidence also implicates adenosine A2A receptors. Objective The present work was undertaken to test the hypothesis that accumbens A2A receptor stimulation would produce effects similar to those produced by DA depletion or antagonism. Materials and methods Three experiments assessed the effects of the adenosine A2A agonist CGS 21680 on performance of a concurrent choice task (lever pressing for preferred food vs. intake of less preferred chow) that is known to be sensitive to DA antagonists and accumbens DA depletions. Results Systemic injections of CGS 21680 reduced lever pressing but did not increase feeding. In contrast, bilateral infusions of the adenosine A2A receptor agonist CGS 21680 (6.0–24.0 ng) into the nucleus accumbens decreased lever pressing for the preferred food but substantially increased consumption of the less preferred chow. Injections of CGS 21680 into a control site dorsal to the accumbens were ineffective. Conclusions Taken together, these results are consistent with the hypothesis that local stimulation of adenosine A2A receptors in nucleus accumbens produces behavioral effects similar to those induced by accumbens DA depletions. Accumbens adenosine A2A receptors appear to be a component of the brain circuitry regulating effort-related choice behavior. PMID:18491078

  8. The tobacco mosaic virus RNA polymerase complex contains a plant protein related to the RNA-binding subunit of yeast eIF-3.

    PubMed Central

    Osman, T A; Buck, K W

    1997-01-01

    A sucrose density gradient-purified, membrane-bound tobacco mosaic virus (tomato strain L) (TMV-L) RNA polymerase containing endogenous RNA template was efficiently solubilized with sodium taurodeoxycholate. Solubilization resulted in an increase in the synthesis of positive-strand, 6.4-kb genome-length single-stranded RNA (ssRNA) and a decrease in the production of 6.4-kbp double-stranded RNA (dsRNA) to levels close to the limits of detection. The solubilized TMV-L RNA polymerase was purified by chromatography on columns of DEAE-Bio-Gel and High Q. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining showed that purified RNA polymerase preparations consistently contained proteins with molecular masses of 183, 126, 56, 54, and 50 kDa, which were not found in equivalent material from healthy plants. Western blotting showed that the two largest of these proteins are the TMV-L-encoded 183- and 126-kDa replication proteins and that the 56-kDa protein is related to the 54.6-kDa GCD10 protein, the RNA-binding subunit of yeast eIF-3. The 126-, 183-, and 56-kDa proteins were coimmunoaffinity selected by antibodies against the TMV-L 126-kDa protein and by antibodies against the GCD10 protein. Antibody-linked polymerase assays showed that active TMV-L RNA polymerase bound to antibodies against the TMV-L 126-kDa protein and to antibodies against the GCD10 protein. Synthesis of genome-length ssRNA and dsRNA by a template-dependent, membrane-bound RNA polymerase was inhibited by antibodies against the GCD10 protein, and this inhibition was reversed by prior addition of GCD10 protein. PMID:9223501

  9. Development of a self-healing soft pneumatic actuator: a first concept.

    PubMed

    Terryn, Seppe; Mathijssen, Glenn; Brancart, Joost; Lefeber, Dirk; Assche, Guy Van; Vanderborght, Bram

    2015-07-07

    Inspired by the intrinsic softness and the corresponding embodied intelligence principles, soft pneumatic actuators (SPA) have been developed, which ensure safe interaction in unstructured, unknown environments. Due to their intrinsic softness, these actuators have the ability to resist large mechanical impacts. However, the soft materials used in these structures are in general susceptible to damage caused by sharp objects found in the unstructured environments. This paper proposes to integrate a self-healing (SH-) mechanism in SPAs, such that cuts, tears and perforations in the actuator can be self-healed. Diels-Alder (DA-) polymers, covalent polymer network systems based on the thermoreversible DA-reaction, were selected and their mechanical, as well as SH-properties, are described. To evaluate the feasibility of developing an SPA constructed out of SH-material, a single cell prototype, a SH-soft pneumatic cell (SH-SPC), was constructed entirely out of DA-polymers. Exploiting the SH-property of the DA-polymers, a completely new shaping process is presented in this paper, referred to as 'shaping through folding and self-healing'. 3D polygon structures, like the cubic SH-SPC, can be constructed by folding SH-polymer sheet. The sides of the structures can be sealed and made airtight using a SH-procedure at relatively low temperatures (<90 °C). Both the (thermo) mechanical and SH-properties of the SH-SPC prototype were experimentally validated and showed excellent performances. Macroscopic incisions in the prototype were completely healed using a SH-procedure (<70 °C). Starting from this single-cell prototype, it is straight-forward to develop a multi-cell prototype, the first SPA ever built completely out of SH-polymers.

  10. Creep and Fracture Characteristics of Materials and Structures at Elevated Temperatures

    DTIC Science & Technology

    1988-05-01

    evident until the crack velocity and length have grown appreciably. At the larger da/dt values, many of the assumptions required for the application of the...to difficulties in the practical application of the energy balance concept, new approaches had to be found to characterize the material behavior...fracture mechanics (LEFM). Irwin [8] broadened the applicability of LEFM by introducing a modified stress intensity factor KI. At the same time Wells [9

  11. Tribosystems based on multilayered micro/nanocrystalline CVD diamond coatings =

    NASA Astrophysics Data System (ADS)

    Shabani, Mohammadmehdi

    A combinacao das caracteristicas do diamante microcristalino (MCD) e nanocristalino (NCD), tais como elevada adesao do MCD e a baixa rugosidade superficial e baixo coeficiente de atrito do NCD, e ideal para aplicacoes tribologicas exigentes. Deste modo, o presente trabalho centrou-se no desenvolvimento de revestimentos em multicamada MCD/NCD. Filmes com dez camadas foram depositados em amostras de cerâmicos de Si3N4 pela tecnica de deposicao quimica em fase vapor assistida por filamento quente (HFCVD). A microestrutura, qualidade do diamante e adesao foram investigadas usando tecnicas como SEM, AFM, espectroscopia Raman, DRX, indentacao Brale e perfilometria otica 3D. Diversas geometrias para aplicacoes distintas foram revestidas: discos e esferas para testes tribologicos a escala laboratorial, e para testes em servico, aneis de empanques mecânicos e pastilhas de corte para torneamento. Nos ensaios tribologicos esfera-sobre-plano em movimento reciproco, sob 10-90% de humidade relativa (RH), os valores medios dos coeficientes de atrito maximo e em estado estacionario sao de 0,32 e 0,09, respetivamente. Em relacao aos coeficientes de desgaste, observou-se um valor minimo de cerca de 5,2x10-8 mm3N-1m-1 para valores intermedios de 20-25% de RH. A humidade relativa tem um forte efeito sobre o valor da carga critica que triplica a partir de 40 N a 10% RH para 120 N a 90% de RH. No intervalo de temperaturas 50-100 °C, as cargas criticas sao semelhantes as obtidas em condicoes de baixa RH ( 10-25%). A vida util das ferramentas com revestimento de dez camadas alternadas MCD/NCD e 24 mum de espessura total no torneamento de um composito de matriz metalica Al- 15 vol% Al2O3 (Al-MMC) e melhor do que a maioria das ferramentas de diamante CVD encontradas na literatura, e semelhante a maioria das ferramentas de diamante policristalino (PCD). A formacao de cratera ocorre por desgaste sucessivo das varias camadas, atrasando a delaminacao total do revestimento de diamante do substrato, ao contrario do que acontece com os revestimentos monocamada. Os aneis de empanque testados com biodiesel apresentaram coeficientes de desgaste (4,1x10-10 mm3N-1m-1) duas ordens de grandeza menores do que em ensaios esfera-sobre-plano em movimento reciproco (k = 5,0x10-8 mm3N-1m-1), mas nao foi possivel obter vedacao completa devido a sobreaquecimento do fluido. Esta condicao foi obtida com agua sob pressao, para condicoes P.V na gama 0,72-5,3 MPa.ms-1. Um coeficiente de atrito em estado estacionario de 0,04 e um valor de coeficiente de desgaste de 6,0x10-10 mm3N-1m-1, caracteristico de um regime desgaste ultra-suave, revelam o alto desempenho deste tribossistema.

  12. On Healable Polymers and Fiber-Reinforced Composites

    NASA Astrophysics Data System (ADS)

    Nielsen, Christian Eric

    Polymeric materials capable of healing damage would be valuable in structural applications where access for repair is limited. Approaches to creating such materials are reviewed, with the present work focusing on polymers with thermally reversible covalent cross-links. These special cross-links are Diels-Alder (DA) adducts, which can be separated and re-formed, enabling healing of mechanical damage at the molecular level. Several DA-based polymers, including 2MEP4FS, are mechanically and thermally characterized. The polymerization reaction of 2MEP4FS is modeled and the number of established DA adducts is associated with the glass transition temperature of the polymer. The models are applied to concentric cylinder rotational measurements of 2MEP4FS prepolymer at room and elevated temperatures to describe the viscosity as a function of time, temperature, and conversion. Mechanical damage including cracks and scratches are imparted in cured polymer samples and subsequently healed. Damage due to high temperature thermal degradation is observed to not be reversible. The ability to repair damage without flowing polymer chains makes DA-based healable polymers particularly well-suited for crack healing. The double cleavage drilled compression (DCDC) fracture test is investigated as a useful method of creating and incrementally growing cracks in a sample. The effect of sample geometry on the fracture behavior is experimentally and computationally studied. Computational and empirical models are developed to estimate critical stress intensity factors from DCDC results. Glass and carbon fiber-reinforced composites are fabricated with 2MEP4FS as the matrix material. A prepreg process is developed that uses temperature to control the polymerization rate of the monomers and produce homogeneous prepolymer for integration with a layer of unidirectional fiber. Multiple prepreg layers are laminated to form multi-layered cross-ply healable composites, which are characterized in bending using dynamic mechanical analysis (DMA). Simple, theory-based analyses indicate that numerous cracks are present before testing due to thermal expansion mismatches, and during testing, these cracks must be healing. Extending healable composites to include healable fiber-matrix interfaces is discussed as future work and interfacial healing characterization approaches are considered.

  13. Potencial de Seqüestro de Carbono Atmosférico entre Diferentes Cultivares de Milho (Zea mays L.) sob Condiç o de Déficit Hídrico

    USDA-ARS?s Scientific Manuscript database

    There is a question concerning the role of agricultural practices on carbon sequestration enhancement. By producing biomass with agricultural crops and adding this residue to soil, it should act on the mitigation process of the greenhouse effect, especially CO2. The objectives of this study were to ...

  14. Preparation of porous carbons from polymeric precursors modified with acrylated kraft lignin

    NASA Astrophysics Data System (ADS)

    Sobiesiak, M.

    2016-04-01

    The presented studies concern the preparation of porous carbons from a BPA.DA-St polymer containing acrylated kraft lignin as a monomer. The porous polymeric precursor in the form of microspheres was synthesized in suspension polymerization process. Next samples of the polymer were impregnated with acetic acid or aqueous solution of acetates (potassium or ammonia), dried and carbonised in nitrogen atmosphere at 450°C. After carbonization microspherical shape of the materials was remained, that is desired feature for potential application in chromatography or SPE technique. Chemical and textural properties of the porous carbon adsorbents were characterized using infrared spectroscopy (ATR-FTIR), thermogravimetry analyses with mass spectrometry of released gases (TG-MS) and nitrogen sorption experiments. The presented studies revealed the impregnation is useful method for development of porous structure of carbonaceous materials. The highest values of porous structure parameters were obtained when acetic acid and ammonium acetate were used as impregnating substances. On the surface of the materials oxygen functional groups are present that is important for specific interactions during sorption processes. The highest contents of functionalities were observed for carbon BPA.DA-St-LA-C-AcNH4.

  15. Evaluation of powder metallurgy superalloy disk materials

    NASA Technical Reports Server (NTRS)

    Evans, D. J.

    1975-01-01

    A program was conducted to develop nickel-base superalloy disk material using prealloyed powder metallurgy techniques. The program included fabrication of test specimens and subscale turbine disks from four different prealloyed powders (NASA-TRW-VIA, AF2-1DA, Mar-M-432 and MERL 80). Based on evaluation of these specimens and disks, two alloys (AF2-1DA and Mar-M-432) were selected for scale-up evaluation. Using fabricating experience gained in the subscale turbine disk effort, test specimens and full scale turbine disks were formed from the selected alloys. These specimens and disks were then subjected to a rigorous test program to evaluate their physical properties and determine their suitability for use in advanced performance turbine engines. A major objective of the program was to develop processes which would yield alloy properties that would be repeatable in producing jet engine disks from the same powder metallurgy alloys. The feasibility of manufacturing full scale gas turbine engine disks by thermomechanical processing of pre-alloyed metal powders was demonstrated. AF2-1DA was shown to possess tensile and creep-rupture properties in excess of those of Astroloy, one of the highest temperature capability disk alloys now in production. It was determined that metallographic evaluation after post-HIP elevated temperature exposure should be used to verify the effectiveness of consolidation of hot isostatically pressed billets.

  16. Control of the interparticle spacing in superparamagnetic iron oxide nanoparticle clusters by surface ligand engineering

    NASA Astrophysics Data System (ADS)

    Dan, Wang; Bingbing, Lin; Taipeng, Shen; Jun, Wu; Fuhua, Hao; Chunchao, Xia; Qiyong, Gong; Huiru, Tang; Bin, Song; Hua, Ai

    2016-07-01

    Polymer-mediated self-assembly of superparamagnetic iron oxide (SPIO) nanoparticles allows modulation of the structure of SPIO nanocrystal cluster and their magnetic properties. In this study, dopamine-functionalized polyesters (DA-polyester) were used to directly control the magnetic nanoparticle spacing and its effect on magnetic resonance relaxation properties of these clusters was investigated. Monodisperse SPIO nanocrystals with different surface coating materials (poly(ɛ-caprolactone), poly(lactic acid)) of different molecular weights containing dopamine (DA) structure (DA-PCL2k, DA-PCL1k, DA-PLA1k)) were prepared via ligand exchange reaction, and these nanocrystals were encapsulated inside amphiphilic polymer micelles to modulate the SPIO nanocrystal interparticle spacing. Small-angle x-ray scattering (SAXS) was applied to quantify the interparticle spacing of SPIO clusters. The results demonstrated that the tailored magnetic nanoparticle clusters featured controllable interparticle spacing providing directly by the different surface coating of SPIO nanocrystals. Systematic modulation of SPIO nanocrystal interparticle spacing can regulate the saturation magnetization (M s) and T 2 relaxation of the aggregation, and lead to increased magnetic resonance (MR) relaxation properties with decreased interparticle spacing. Project supported by the National Key Basic Research Program of China (Grant No. 2013CB933903), the National Key Technology R&D Program of China (Grant No. 2012BAI23B08), and the National Natural Science Foundation of China (Grant Nos. 20974065, 51173117, and 50830107).

  17. Molecular weight dependence of carrier mobility and recombination rate in neat P3HT films

    DOE PAGES

    Dixon, Alex G.; Visvanathan, Rayshan; Clark, Noel A.; ...

    2017-11-02

    The microstructure dependence of carrier mobility and recombination rates of neat films of poly 3-hexylthyophene (P3HT) were determined for a range of materials of weight-average molecular weights, Mw, ranging from 14 to 331 kDa. This variation has previously been shown to modify the polymer microstructure, with low molecular weights forming a one-phase, paraffinic-like structure comprised of chain-extended crystallites, and higher molecular weights forming a semicrystalline structure with crystalline domains being embedded in an amorphous matrix. Using Charge Extraction by Linearly Increasing Voltage (CELIV), we show here that the carrier mobility in P3HT devices peaks for materials of Mw = 48more » kDa, and that the recombination rate decreases monotonically with increasing molecular weight. This trend is likely due to the development of a semicrystalline, two-phase structure with increasing Mw, which allows for the spatial separation of holes and electrons into the amorphous and crystalline regions, respectively. This separation leads to decreased recombination.« less

  18. Molecular weight dependence of carrier mobility and recombination rate in neat P3HT films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dixon, Alex G.; Visvanathan, Rayshan; Clark, Noel A.

    The microstructure dependence of carrier mobility and recombination rates of neat films of poly 3-hexylthyophene (P3HT) were determined for a range of materials of weight-average molecular weights, Mw, ranging from 14 to 331 kDa. This variation has previously been shown to modify the polymer microstructure, with low molecular weights forming a one-phase, paraffinic-like structure comprised of chain-extended crystallites, and higher molecular weights forming a semicrystalline structure with crystalline domains being embedded in an amorphous matrix. Using Charge Extraction by Linearly Increasing Voltage (CELIV), we show here that the carrier mobility in P3HT devices peaks for materials of Mw = 48more » kDa, and that the recombination rate decreases monotonically with increasing molecular weight. This trend is likely due to the development of a semicrystalline, two-phase structure with increasing Mw, which allows for the spatial separation of holes and electrons into the amorphous and crystalline regions, respectively. This separation leads to decreased recombination.« less

  19. Recognition unit-free and self-cleaning photoelectrochemical sensing platform on TiO2 nanotube photonic crystals for sensitive and selective detection of dopamine release from mouse brain.

    PubMed

    Xin, Yanmei; Li, Zhenzhen; Wu, Wenlong; Fu, Baihe; Wu, Hongjun; Zhang, Zhonghai

    2017-01-15

    For implementing sensitive and selective detection of biological molecules, the biosensors are been designed more and more complicated. The exploration of detection platform in a simple way without loss their sensitivity and selectivity is always a big challenge. Herein, a prototype of recognition biomolecule unit-free photoelectrochemical (PEC) sensing platform with self-cleaning activity is proposed with TiO 2 nanotube photonic crystal (TiO 2 NTPCs) materials as photoelectrode, and dopamine (DA) molecule as both sensitizer and target analyte. The unique adsorption between DA and TiO 2 NTPCs induces the formation of charge transfer complex, which not only expends the optical absorption of TiO 2 into visible light region, thus significantly boosts the PEC performance under illumination of visible light, but also implements the selective detection of DA on TiO 2 photoelectrode. This simple but efficient PEC analysis platform presents a low detection limit of 0.15nm for detection of DA, which allows to realize the sensitive and selective determination of DA release from the mouse brain for its practical application after coupled with a microdialysis probe. The DA functionalized TiO 2 NTPCs PEC sensing platform opens up a new PEC detection model, without using extra-biomolecule auxiliary, just with target molecule naturally adsorbed on the electrode for sensitive and selective detection, and paves a new avenue for biosensors design with minimalism idea. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Evaluation of Parkinson's disease by neuromelanin-sensitive magnetic resonance imaging and 123I-FP-CIT SPECT.

    PubMed

    Kuya, Keita; Ogawa, Toshihide; Shinohara, Yuki; Ishibashi, Mana; Fujii, Shinya; Mukuda, Naoko; Tanabe, Yoshio

    2018-05-01

    Background Both neuromelanin-sensitive magnetic resonance imaging (NmMRI) and 123 I-FP-CIT single photon emission computed tomography (SPECT) (DaTSCAN) assist the diagnosis of Parkinson's disease (PD). However, there have been few studies investigating a correlation between them. Purpose To correlate the utility of NmMRI and DaTSCAN and to evaluate the relationship between both imaging findings and the Unified PD rating scale part III (UPDRS III) score for the diagnosis and management of PD. Material and Methods Seventeen patients with PD who underwent both NmMRI and DaTSCAN were included. We measured the volume of the neuromelanin-positive substantia nigra pars compacta (SNc volume) on NmMRI and measured the specific binding ratio (SBR) on DaTSCAN. The asymmetry index (AI) of the SNc volume and SBR were also calculated. We evaluated the relationship between the UPDRS III score and the SNc volume and SBR, respectively. Results The SNc volume showed a significant correlation with the SBR. The AIs of them also showed a significant correlation. Both the mean of the bilateral SBR and the mean of the bilateral SNc volume showed significant negative correlations with the UPDRS III score. However, the correlation between the SBR and the UPDRS III score was stronger than that between the SNc volume and the UPDRS III score. Conclusion Both NmMRI and DaTSCAN are helpful for PD diagnosis. However, we conclude that DaTSCAN is more suitable for the evaluation of the clinical motor severity and would be more useful for the management of PD patients than NmMRI.

  1. Ensino de gravitação clássica no nível médio: uma proposta de abordagem e resultados preliminares

    NASA Astrophysics Data System (ADS)

    Medeiros, G. C. M.; Jafelice, L. C.

    2003-08-01

    O ensino de gravitação clássica é comumente realizado de maneira formal e descontextualizado da experiência com a força-peso e da história do tema. Fustigados por anos de experiência de ensino no assunto, nem sempre com bons resultados, propomos uma abordagem ancorada nos eixos: a) contextualização histórica; e b) reconhecimento do peso como a força de atração gravitacional. O primeiro eixo integra o tema no desenvolvimento cultural do ser humano, praticando a interdisciplinaridade. O segundo eixo embasa construtivamente a abordagem, levando o aluno a realizar experiências e a vivenciar o reconhecimento de uma força universal. A abordagem foi construída através das etapas: 1) análise crítica do tema em livros didáticos; 2) elaboração de um curso para professores das várias disciplinas do ensino médio, identificando conexões para a prática da interdisciplinaridade; 3) elaboração de material didático; e 4) avaliação da eficácia da abordagem. No trabalho discutimos em detalhe as quatro etapas. Como resultados, adiantamos que: tabulamos a abordagem de gravitação nos livros didáticos, ainda muito tradicional e carecedora de atividades criativas que poderiam melhor explorar esse assunto; mapeamos, junto aos professores, padrões de conceitos espontâneos e erros associados ao tema; e, no curso, adaptamos e testamos a eficiência de materiais instrucionais existentes e criamos outros novos (e.g., para trabalhar excentricidades das órbitas planetárias), além disto elaboramos roteiros e figuras para tratamentos qualitativo e quantitativo da lei da gravitação universal. As avaliações feitas pelos professores foram muito animadoras. O espaço da presente reunião será aproveitado para socializar a proposta e os resultados obtidos e para submeter o projeto à análise crítica. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP)

  2. Hydrolysis of lignocellulosic feedstock by novel cellulases originating from Pseudomonas sp. CL3 for fermentative hydrogen production.

    PubMed

    Cheng, Chieh-Lun; Chang, Jo-Shu

    2011-09-01

    A newly isolated indigenous bacterium Pseudomonas sp. CL3 was able to produce novel cellulases consisting of endo-β-1,4-d-glucanase (80 and 100 kDa), exo-β-1,4-d-glucanase (55 kDa) and β-1,4-d-glucosidase (65 kDa) characterized by enzyme assay and zymography analysis. In addition, the CL3 strain also produced xylanase with a molecular weight of 20 kDa. The optimal temperature for enzyme activity was 50, 45, 45 and 55 °C for endo-β-1,4-d-glucanase, exo-β-1,4-d-glucanase, β-1,4-d-glucosidase and xylanase, respectively. All the enzymes displayed optimal activity at pH 6.0. The cellulases/xylanase could hydrolyze cellulosic materials very effectively and were thus used to hydrolyze natural agricultural waste (i.e., bagasse) for clean energy (H2) production by Clostridium pasteurianum CH4 using separate hydrolysis and fermentation process. The maximum hydrogen production rate and cumulative hydrogen production were 35 ml/L/h and 1420 ml/L, respectively, with a hydrogen yield of around 0.96 mol H2/mol glucose. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. In vitro and in vivo anti-inflammatory activities of high molecular weight sulfated polysaccharide; containing fucose separated from Sargassum horneri: Short communication.

    PubMed

    Sanjeewa, K K Asanka; Fernando, I P S; Kim, Seo-Young; Kim, Hyun-Soo; Ahn, Ginnae; Jee, Youngheun; Jeon, You-Jin

    2018-02-01

    Recent studies on crude and pure compounds from Sargassum horneri have shown promising bioactive properties. However, anti-inflammatory potentials of fucose-rich sulfated polysaccharides from S. horneri have not yet been discovered. In the present study, we evaluated the in vitro and in vivo anti-inflammatory activities of four polysaccharide fractions separated from membrane filters according to their molecular weights (<5kDa (f1), 5-10kDa (f2), 10-30kDa (f3), and >30kDa (f4)). According to the results, F4 fraction inhibited the lipopolysaccharides (LPS)-induced nitric oxide (NO) (IC 50 =87.12μg/mL) and prostaglandin E 2 production as well as pro-inflammatory cytokine production in RAW 264.7 cells through down-regulating nuclear factor-κB signaling cascade. According to the results, f4 has a potential to down-regulate LPS-induced toxicity, cell death and NO production levels in LPS-induced in vivo zebrafish embryo model. These results suggest that f4 fraction has the potential to develop functional materials or drugs to treat inflammatory diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. A Study to Improve the Brazilian Air Force’s Material Management System

    DTIC Science & Technology

    1991-12-01

    of Technology, in June 1990. Permanent Address: Base A6rea de Sio Paulo Instituto de Logistica da Aerongutica 07181 Guarulhos Sio Paulo Brazil 160 Vita...orders instead of more frequent smaller ones, and transportation from vendor to depot, which includes international fees in most cases, would be...optimized by the same reason. The transportation from depots to final users would not be affected, since only changes of depots and changes of material

  5. Impact of the De-Alloying Kinetics and Alloy Microstructure on the Final Morphology of De-Alloyed Meso-Porous Metal Films

    PubMed Central

    Lin, Bao; Kong, Lingxue; Hodgson, Peter D.; Dumée, Ludovic F.

    2014-01-01

    Nano-textured porous metal materials present unique surface properties due to their enhanced surface energy with potential applications in sensing, molecular separation and catalysis. In this paper, commercial alloy foils, including brass (Cu85Zn15 and Cu70Zn30) and white gold (Au50Ag50) foils have been chemically de-alloyed to form nano-porous thin films. The impact of the initial alloy micro-structure and number of phases, as well as chemical de-alloying (DA) parameters, including etchant concentration, time and solution temperature on the final nano-porous thin film morphology and properties were investigated by electron microscopy (EM). Furthermore, the penetration depth of the pores across the alloys were evaluated through the preparation of cross sections by focus ion beam (FIB) milling. It is demonstrated that ordered pores ranging between 100 nm and 600 nm in diameter and 2–5 μm in depth can be successfully formed for the range of materials tested. The microstructure of the foils were obtained by electron back-scattered diffraction (EBSD) and linked to development of pits across the material thickness and surface during DA. The role of selective etching of both noble and sacrificial metal phases of the alloy were discussed in light of the competitive surface etching across the range of microstructures and materials tested. PMID:28344253

  6. Mathematical modeling of simultaneous carbon-nitrogen-sulfur removal from industrial wastewater.

    PubMed

    Xu, Xi-Jun; Chen, Chuan; Wang, Ai-Jie; Ni, Bing-Jie; Guo, Wan-Qian; Yuan, Ye; Huang, Cong; Zhou, Xu; Wu, Dong-Hai; Lee, Duu-Jong; Ren, Nan-Qi

    2017-01-05

    A mathematical model of carbon, nitrogen and sulfur removal (C-N-S) from industrial wastewater was constructed considering the interactions of sulfate-reducing bacteria (SRB), sulfide-oxidizing bacteria (SOB), nitrate-reducing bacteria (NRB), facultative bacteria (FB), and methane producing archaea (MPA). For the kinetic network, the bioconversion of C-N by heterotrophic denitrifiers (NO 3 - →NO 2 - →N 2 ), and that of C-S by SRB (SO 4 2- →S 2- ) and SOB (S 2- →S 0 ) was proposed and calibrated based on batch experimental data. The model closely predicted the profiles of nitrate, nitrite, sulfate, sulfide, lactate, acetate, methane and oxygen under both anaerobic and micro-aerobic conditions. The best-fit kinetic parameters had small 95% confidence regions with mean values approximately at the center. The model was further validated using independent data sets generated under different operating conditions. This work was the first successful mathematical modeling of simultaneous C-N-S removal from industrial wastewater and more importantly, the proposed model was proven feasible to simulate other relevant processes, such as sulfate-reducing, sulfide-oxidizing process (SR-SO) and denitrifying sulfide removal (DSR) process. The model developed is expected to enhance our ability to predict the treatment of carbon-nitrogen-sulfur contaminated industrial wastewater. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Rationale and design of the IMPACT EU-trial: improve management of heart failure with procalcitonin biomarkers in cardiology (BIC)-18.

    PubMed

    Möckel, Martin; Slagman, Anna; Vollert, Jörn Ole; Ebmeyer, Stefan; Wiemer, Jan C; Searle, Julia; Giannitsis, Evangelos; Kellum, John A; Maisel, Alan

    2018-02-01

    To evaluate the effectiveness of procalcitonin (PCT)-guided antibiotic treatment compared to current treatment practice to reduce 90-day all-cause mortality in emergency patients with shortness of breath (SOB) and suspected acute heart failure (AHF). Concomitant AHF and lower respiratory tract (or other bacterial) infection in emergency patients with dyspnea are common and can be difficult to diagnose. Early and adequate initiation of antibiotic therapy (ABX) significantly improves patient outcome, but superfluous prescription of ABX maybe harmful. In a multicentre, prospective, randomized, controlled process trial with an open intervention, adult emergency patients with SOB and increased levels of natriuretic peptides will be randomized to either a standard care group or a PCT-guided group with respect to the initiation of antibiotic treatment. In the PCT-guided group, the initiation of antibiotic therapy is based on the results of acute PCT measurements at admission, using a cut-off of 0.2 ng/ml. A two-stage sample-size adaptive design is used; an interim analysis was done after completion of 50% of patients and the final sample size remained unchanged. Primary endpoint is 90-day all-cause mortality. The current study will provide evidence, whether the routine use of PCT in patients with suspected AHF improves outcome.

  8. Oat raw materials and bakery products - amino acid composition and celiac immunoreactivity.

    PubMed

    Mickowska, Barbara; Litwinek, Dorota; Gambuś, Halina

    2016-01-01

    The aim of this study was to compare the biochemical and immunochemical properties of avenins in some special oat raw materials and additionally the possibility of using them as a raw material for the gluten-free bakery products. The compared oat raw materials were - oat flakes, commercial oat flours (including gluten-free oat flour) and residual oat flour, which is by-product of β-glucan preparation. Biochemical characteristic included amino acid compositions and SDS-PAGE profiles of extracted avenins. The immunochemical reactivity with polyclonal anti-gluten and monoclonal anti-gliadin antibodies was evaluated qualitatively and quantitatively by immunoblotting and ELISA methods. Additionally, experimental bakery products made of examined raw materials were assessed according to their suitability for the celiac patients' diet. The highest protein content was measured in the β-glucan preparation "Betaven" and gluten-free oat flour. Proteins of all materials are rich in glutamic and aspartic acid, leucine and arginine. Proportions of amino acids in avenins extracted from most of oat raw materials are similar, excluding gluten-free oat flour, which has a very low avenin content and proportions of individual amino acids are different. The SDS-PAGE protein pattern consisted of proteins with molecular weight of about 25-35 kDa. Polyclonal anti-gluten anti-body recognized all protein fractions of molecular weight higher than 20 kDa. Quantitative ELISA analysis shows that the majority of samples has a gliadin-like protein content within the range of 80-260 mg/kg, excluding gluten-free flours and corresponding bakery products. Altogether, β-glucan preparation has extremely high level of gliadin-like proteins. In the examined oat raw materials and foods the contents of immunoreactive amino acid sequences exceeded the limit of 20 mg/kg (considered as gluten-free) except for gluten-free flours (oat and  the prepared mixture) and the bakery products based on gluten-free flours. Unfortunately, the rest of oat raw materials and products cannot be considered gluten-free.

  9. Chemical modification of corn fiber with ion-exchanging groups

    USDA-ARS?s Scientific Manuscript database

    Pretreated corn fiber was chemically modified with quaternary ammonium group or/and sulfonated with 3-chloro-2-hydroxypropanesulfonic acid under vacuum or at ambient pressure. The soluble fraction was dialyzed through 1 kDa MWCO dialysis tubing and the material retained inside the tubing was filtere...

  10. A Proposed Activity for a Meaningful Learning about the Moon Phases. (Breton Title: Uma Proposta de Atividade Para a Aprendizagem Significativa sobre as Fases da Lua.) Una Actividad Propuesta Para EL Aprendizaje Significativo Acerca de Las Fases de la Luna

    NASA Astrophysics Data System (ADS)

    Martins, Bruno Andrade; Langhi, Rodolfo

    2012-12-01

    This paper presents one of the concepts of Astronomy and its consequent failure in teaching this topic in high school, even when the official documents point out the necessity of Astronomy teaching at this school level. Among the spontaneous conceptions in Astronomy that high school students carry with them, even after the end of the school, we emphasized in this research the Moon phases. The development of different strategies in relation to traditional methods, aimed to teaching-learning process on this topic was considered in this study. These strategies were devised based on the reference frame of the Meaningful Learning, as elaborated by Ausubel. The proposals presented here include the active participation of students in experimental activities and other didactic activities, for their continuous evaluation during the process. These activities finished with a Comics elaboration about the Moon phases. Therefore, the objective of this paper is to present a proposal for differentiated teaching activity about Moon phases supported by the theoretical principles of Meaningful Learning at Physics classes. Este texto foca um dos conteúdos de Astronomia e a consequente falha no ensino deste tema no ensino médio, apesar de os documentos oficiais apresentarem a necessidade de se trabalhar a Astronomia neste nível de ensino. Dentre as concepções alternativas em Astronomia que os alunos do ensino médio carregam consigo, mesmo após o término dos estudos, destacamos, nesta pesquisa, o fenômeno das fases da Lua. O desenvolvimento de estratégias diferenciadas em relação ao ensino tradicional, visando o processo de ensino-aprendizagem sobre este tema, foi contemplado neste trabalho como um dos resultados obtidos sob a luz dos referenciais da aprendizagem significativa, fundamentados em Ausubel. Segundo a proposta aqui apresentada, a participação ativa dos alunos na execução de uma atividade experimental e outras atividades didáticas, que visam sua contínua avaliação durante o processo, culmina com a elaboração de uma história em quadrinhos envolvendo as fases da Lua. Portanto, o objetivo deste trabalho é apresentar uma proposta de atividade didática diferenciada sustentada pelos princípios teóricos da aprendizagem significativa aplicada ao ensino das fases da Lua durante as aulas de Física no ensino médio. En este trabajo se presenta uno de los contenidos de la Astronomía y el evidente fracaso en la enseñanza del tema en la escuela secundaria, a pesar del hecho que los documentos oficiales apuntan para la necesidad de trabajar contenidos de Astronomía en este nivel. Entre los conceptos alternativos en Astronomía que los alumnos secundarios llevan consigo, aún después de terminados los estudios, destacamos aquí el fenómeno de las fases de la Luna. El desarrollo de diferentes estrategias en relación con los métodos tradicionales, dirigidas al proceso de enseñanza-aprendizaje en este tema fue considerado en este trabajo como uno de los resultados obtenidos a la luz de los referenciales del aprendizaje significativo, tal como fueron fundamentados por Ausubel. Según la propuesta que aquí se presenta, la participación activa de los estudiantes en la ejecución de una actividad experimental y otras actividades educativas destinadas a la evaluación continua durante el proceso culminó en la elaboración de una historieta respecto de las fases de la Luna. Por lo tanto, el objetivo de este trabajo es presentar una propuesta de actividad de enseñanza diferenciada con el apoyo de los principios teóricos del aprendizaje significativo aplicado a la enseñanza de las fases de la luna durante las clases de física del ciclo secundario.

  11. Comparative study of abdominal cavity temporary closure techniques for damage control.

    PubMed

    Ribeiro, Marcelo A F; Barros, Emily Alves; Carvalho, Sabrina Marques DE; Nascimento, Vinicius Pereira; Cruvinel, José; Fonseca, Alexandre Zanchenko

    2016-01-01

    The damage control surgery, with emphasis on laparostomy, usually results in shrinkage of the aponeurosis and loss of the ability to close the abdominal wall, leading to the formation of ventral incisional hernias. Currently, various techniques offer greater chances of closing the abdominal cavity with less tension. Thus, this study aims to evaluate three temporary closure techniques of the abdominal cavity: the Vacuum-Assisted Closure Therapy - VAC, the Bogotá Bag and the Vacuum-pack. We conducted a systematic review of the literature, selecting 28 articles published in the last 20 years. The techniques of the bag Bogotá and Vacuum-pack had the advantage of easy access to the material in most centers and low cost, contrary to VAC, which, besides presenting high cost, is not available in most hospitals. On the other hand, the VAC technique was more effective in reducing stress at the edges of lesions, removing stagnant fluids and waste, in addition to acting at the cellular level by increasing proliferation and cell division rates, and showed the highest rates of primary closure of the abdominal cavity. RESUMO A cirurgia de controle de danos, com ênfase em peritoneostomia, geralmente resulta em retração da aponeurose e perda da capacidade de fechar a parede abdominal, levando à formação de hérnias ventrais incisionais. Atualmente, várias técnicas oferecem maiores chances de fechamento da cavidade abdominal, com menor tensão. Deste modo, este estudo tem por objetivo avaliar três técnicas de fechamento temporário da cavidade abdominal: fechamento a vácuo (Vacuum-Assisted Closure Therapy - VAC), Bolsa de Bogotá e Vacuum-pack. Realizou-se uma revisão sistemática da literatura com seleção de 28 artigos publicados nos últimos 20 anos. As técnicas de Bolsa de Bogotá e Vacuum-pack tiveram como vantagem o acesso fácil ao material, na maioria dos centros, e baixo custo, ao contrário do que se observa na terapia a vácuo, VAC, que além de apresentar alto custo, não está disponível em grande parte dos hospitais. A técnica VAC, por outro lado, foi mais eficaz na redução da tensão nas bordas das lesões, ao remover fluidos estagnados e detritos, além de exercer ação a nível celular, aumentando as taxas de proliferação e divisão celular, e apresentou as maiores taxas de fechamento primário da cavidade abdominal.

  12. Damage Tolerant Design Handbook. A Compilation of Fracture and Crack- Growth Data for High-Strength Alloys. Volume 3

    DTIC Science & Technology

    1983-12-01

    Effects on the Fatigue Crack Growth Rate of Aluminum Alloy 2024 - T351 ", University of Dayton Research Institute, Dayton, OH, Contract No. F33615-80-C-5011...ASSOCIATED WITH FIGURE 7.5.3.9 INDICATING EFFECT OF STRESS RATIO MATERIAL: ALUMINUM 2024 CONDITION: T351 ENVIRONMENT: R.T. LAB AIR DELTA K .DA/DN (10...OF STRESS INTENSITY FACTOR DATA ASSOCIATED WITH FIGURE 7.5.3.10 INDICATING EFFECT OF STRESS RATIO MATERIAL: ALUMINUM 2024

  13. Development of Engineering Data on Advanced Composite Materials

    DTIC Science & Technology

    1977-09-01

    O AFML-TR-77-15 1 ,* • DEVELOPMENT OF ENGINEERING DATA ON ’ ADVANCED COMPOSITE MATERIALS UNIVERSITY OF DAYTON RESEARCH INSTITUTE I - UNIVERSITY OF DA...SUMMARIZED COMPOSITE DATA 47 4.1 SP313 48 4.2 AS/3004 86 4.3 AS/4397 125 4.4 T300/F178 163 4.5 COMPARATIVE ENVIRONMENTAL BEHAVIOR 194 5 CONCLUSIONS 197...AGED INTERLAKINAR SHEAR DATA 452 vi -. -| |b. ~ - LIST OF ILLUSTRATIONS FIGURE PACE 1 Typical Cross Sections of Fabricated Composites 12 2 Heat-Up

  14. Intermetallic Matrix Composites 3 Symposium Held in San Francisco, California on April 4 - 6, 1994. Materials Research Society Symposium Proceedings. Volume 350

    DTIC Science & Technology

    1994-04-06

    Structure. Texture , Properties and Applications. M. Parker. K. Barmak. R. Sinclair. D.A. Smith. J. Floro. 1994. ISBN: 1-55899-243-X Volume 344- Materials...Schematic of the tensile Fractography revealed that the Ni specimen, layer in the Ni-Al composites necked to a knife edge and multiple cracks formed...fibers. Thermochemical and mechanical properties, as well as fractography and microstructure will be presented. INTRODUCTION Polycrystalline silicon

  15. Photocurable poly(ethylene glycol) as a bioink for the inkjet 3D pharming of hydrophobic drugs.

    PubMed

    Acosta-Vélez, Giovanny F; Zhu, Timothy Z; Linsley, Chase S; Wu, Benjamin M

    2018-04-26

    Binder jetting and material extrusion are the two most common additive manufacturing techniques used to create pharmaceutical tablets. However, their versatility is limited since the powder component is present throughout the dosage forms fabricated by binder jet 3D printing and material extrusion 3D printing requires high operating temperatures. Conversely, material jetting allows for compositional control at a voxel level and can dispense material at room temperature. Unfortunately, there are a limited number of materials that are both printable and biocompatible. Therefore, the aim of this study was to engineer photocurable bioinks that are suitable for hydrophobic active pharmaceutical ingredients and have rapid gelation times upon visible light exposure. The resulting bioinks were comprised of poly(ethylene glycol) diacrylate (250 Da) as the crosslinkable monomer, Eosin Y as the photoinitiator, and methoxide-poly(ethylene glycol)-amine as the coinitiator. Additionally, poly(ethylene glycol) (200 Da) was added as a plasticizer to modulate the drug release profiles, and Naproxen was used as the model drug due to its high hydrophobicity. Various bioink formulations were dispensed into the bottom half of blank preform tablets - made via direct compression - using a piezoelectric nozzle, photopolymerized, and capped with the top half of the preform tablet to complete the pharmaceutical dosage form. Results from the release studies showed that drug release can be modulated by both the percent of poly(ethylene glycol) diacrylate in the formulation and the light exposure time used to cure the bioinks. These bioinks have the potential to expand the library of materials available for creating pharmaceutical tablets via inkjet printing with personalized drug dosages. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Designing CBE for Continuing Professional Education.

    ERIC Educational Resources Information Center

    Rees, Keith

    Deakin Australia (DA) CBE (Continuing Business Education) programs are designed for use in conjunction with print and audio materials which are distributed as distance learning packages to business studies graduates working or planning to work as accountants, who are enrolled in the professional licensing program run by the Australian Society of…

  17. Identification and quantitative determination of diphenylarsenic compounds in abandoned toxic smoke canisters.

    PubMed

    Hanaoka, Shigeyuki; Nomura, Koji; Kudo, Shinichi

    2005-09-02

    Knowledge of the exact nature of the constituents of abandoned chemical weapons (ACW) is a prerequisite for their orderly destruction. Here we report the development of analytical procedures to identify diphenylchloroarsine (DA/Clark I), diphenylcyanoarsine (DC/Clark II) and related substances employed in one of the munitions known as "Red canister". Both DA and DC are relatively unstable under conventional analytical procedures without thiol derivatization. Unfortunately however, thiol drivatization affords the same volatile organo-arsenic derivative from several different diphenylarsenic compounds, making it impossible to identify and quantify the original compounds. Further, diminishing the analytical interference caused by the celluloid powder used as a stacking material in the weapons, is also essential for accurate analysis. In this study, extraction and instrumental conditions have been evaluated and an optimal protocol was determined. The analysis of Red canister samples following this protocol showed that most of the DA and DC associated with pumice had degraded to bis(diphenylarsine)oxide (BDPAO), while those associated with celluloid were dominantly degraded to diphenylarsinic acid (DPAA).

  18. Interactions of green coffee bean phenolics with wheat bread matrix in a model of simulated in vitro digestion.

    PubMed

    Świeca, Michał; Gawlik-Dziki, Urszula; Sęczyk, Łukasz; Dziki, Dariusz; Sikora, Małgorzata

    2018-08-30

    Interactions of phenolics from green coffee bean flour (GCS) with the matrix of wheat bread have been studied employing direct (electrophoretic and chromatographic techniques) and indirect tests (nutrient digestibility). According to the chromatograms of digests, the antiradical activity of enriched bread was exhibited by free phenolics. An increase the area of chromatograms and some additional peaks observed for enriched bread may confirm some interactions of proteins with phenolics. The electrophoretic profile of these extracts showed that the band corresponding to a protein with molecular mass of 38 kDA had much higher intensity in enriched bread. Electrophoretic analysis of pellets remaining after digestion revealed GCS dose-dependent differences in bands corresponding to proteins with molecular masses of 52 kDa and 23 kDa. The relative digestibility of both starch and proteins was slightly decreased by addition of GCS; however, these changes did not exceed 10%, which justifies the use of this functional material. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Enhancing the Anti-Solvatochromic Two-Photon Fluorescence for Cirrhosis Imaging by Forming a Hydrogen-Bond Network.

    PubMed

    Ren, Tian-Bing; Xu, Wang; Zhang, Qian-Ling; Zhang, Xing-Xing; Wen, Si-Yu; Yi, Hai-Bo; Yuan, Lin; Zhang, Xiao-Bing

    2018-06-18

    Two-photon imaging is an emerging tool for biomedical research and clinical diagnostics. Electron donor-acceptor (D-A) type molecules are the most widely employed two-photon scaffolds. However, current D-A type fluorophores suffer from solvatochromic quenching in aqueous biological samples. To address this issue, we devised a novel class of D-A type green fluorescent protein (GFP) chromophore analogues that form a hydrogen-bond network in water to improve the two-photon efficiency. Our design results in two-photon chalcone (TPC) dyes with 0.80 quantum yield and large two-photon action cross section (210 GM) in water. This strategy to form hydrogen bonds can be generalized to design two-photon materials with anti-solvatochromic fluorescence. To demonstrate the improved in vivo imaging, we designed a sulfide probe based on TPC dyes and monitored endogenous H 2 S generation and scavenging in the cirrhotic rat liver for the first time. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Fractionation and antioxidant properties of rice bran protein hydrolysates stimulated by in vitro gastrointestinal digestion.

    PubMed

    Phongthai, Suphat; D'Amico, Stefano; Schoenlechner, Regine; Homthawornchoo, Wantida; Rawdkuen, Saroat

    2018-02-01

    Rice bran was used as a starting material to prepare protein concentrate through enzyme-assisted extraction. The hydrolysis of protein concentrate under in vitro gastrointestinal digestion (pepsin-trypsin system) greatly improved the antioxidant properties. Rice bran protein hydrolysate was further fractionated by membrane ultrafiltration (UF, F1: molecular weight (MW) <3kDa, F2: MW 3-5kDa, and F3: MW 5-10kDa). Peptides with smaller MW possessed higher antioxidant activities (P<0.05). UF showed a great efficacy to selectively separate the metal-chelating peptides. Tyrosine and phenylalanine had positive correlations with their DPPH & ABTS radicals scavenging activities and ferric reducing antioxidant power (r>0.831). A major peptide fragment was detected at m/z 1088 by a MALDI-TOF mass spectrometry. There is high potential that antioxidative peptides from rice bran might also be produced in the gastrointestinal tract of the human body. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. A review of stent’s failure on patent ductus arteriosus

    NASA Astrophysics Data System (ADS)

    Lazim, Zulfaqih; Ismail, Al Emran; Taib, Ishkrizat; Atan, Bainun Akmal Mohd

    2017-01-01

    This paper presents a review of stent’s failure on patent ductus arteriosus (PDA). Ductus arteriosus (DA) is an opening for newborn babies and some patient that experienced cynotic congenital heart disease (CCHD) should maintain the duct opening for survival. To date, there are no specific research on mechanical stent failure study at DA. The challenging of the stent implantation on PDA is the PDA morphology. The failure of stent in term of stent fracture have been reported and reviewed in this paper. Furthermore, the failure prediction of stent is important for further stent design development. The morphology of PDA, stent type and material used in PDA and method for accessing the failure of stent is reviewed.

  2. Three-Dimensional Volumetric Assessment of Diastolic Function by Cardiac Magnetic Resonance Imaging: The Multi-Ethnic Study of Atherosclerosis (MESA).

    PubMed

    Nacif, Marcelo S; Almeida, Andre L C; Young, Alistair A; Cowan, Brett R; Armstrong, Anderson C; Yang, Eunice; Sibley, Christopher T; Hundley, W Gregory; Liu, Songtao; Lima, Joao Ac; Bluemke, David A

    2017-01-01

    Cardiac Magnetic Resonance is in need of a simple and robust method for diastolic function assessment that can be done with routine protocol sequences. To develop and validate a three-dimensional (3D) model-based volumetric assessment of diastolic function using cardiac magnetic resonance (CMR) imaging and compare the results obtained with the model with those obtained by echocardiography. The study participants provided written informed consent and were included if having undergone both echocardiography and cine steady-state free precession (SSFP) CMR on the same day. Guide points at the septal and lateral mitral annulus were used to define the early longitudinal relaxation rate (E'), while a time-volume curve from the 3D model was used to assess diastolic filling parameters. We determined the correlation between 3D CMR and echocardiography and the accuracy of CMR in classifying the diastolic function grade. The study included 102 subjects. The E/A ratio by CMR was positively associated with the E/A ratio by echocardiography (r = 0.71, p < 0.0001). The early diastolic relaxation velocity by tissue Doppler and longitudinal relaxation rate for the lateral mitral annulus displacement were positively associated (p = 0.007), as were the ratio between Doppler E/e' and CMR E/E' (p = 0.01). CMR-determined normalized peak E (NE) and deceleration time (DT) were able to predict diastolic dysfunction (areas under the curve [AUCs] = 0.70 and 0.72, respectively). In addition, the lateral E/E' ratio showed good utility in identifying diastolic dysfunction (AUC = 0.80). Overall, echocardiography and CMR interobserver and intraobserver agreements were excellent (intraclass correlation coefficient range 0.72 - 0.97). 3D modeling of standard cine CMR images was able to identify study subjects with reduced diastolic function and showed good reproducibility, suggesting a potential for a routine diastolic function assessment by CMR. A ressonância magnética cardíaca necessita de um método simples e robusto para a avaliação da função diastólica que pode ser feito com sequências protocolares de rotina. Desenvolver e validar a avaliação volumétrica da função diastólica através de um modelo tridimensional (3D) com utilização de imagens de ressonância magnética cardíaca (RMC) e comparar os resultados obtidos com este modelo com os obtidos por ecocardiografia. Os participantes do estudo assinaram um termo de consentimento e foram incluídos se tivessem sido submetidos no mesmo dia tanto à ecocardiografia quanto à cine RMC com precessão livre no estado estacionário (steady-state free precession, SSFP). Pontos-guia foram utilizados no anel mitral septal e lateral para definir a velocidade de estiramento no início da diástole (E'), enquanto curvas de volume-tempo do modelo 3D foram utilizadas para avaliar os parâmetros de enchimento diastólico. Foram determinadas a correlação entre a RMC 3D e a ecocardiografia, além da acurácia da RMC em classificar o grau de função diastólica. Ao todo, 102 sujeitos foram incluídos no estudo. A razão E/A pela RMC esteve positivamente associada com a razão E/A obtida pela ecocardiografia (r = 0,71, p < 0,0001). Estiveram positivamente associadas a velocidade de relaxamento diastólico inicial ao Doppler tecidual e a velocidade de relaxamento longitudinal de deslocamento do anel mitral lateral (p = 0,007), bem como a razão entre E/e' por Doppler e E/E' pela RMC (p = 0,01). A velocidade normalizada de pico de enchimento (EM) determinada pela RMC e o tempo de desaceleração (TD) foram capazes de predizer a disfunção diastólica (áreas sob a curva [AUCs] = 0,70 e 0,72, respectivamente). Além disso, a razão E/E' lateral mostrou boa utilidade para a identificação da disfunção diastólica (AUC = 0,80). No geral, a ecocardiografia e a RMC apresentaram excelente concordância interobservador e intraobservador (coeficiente de correlação intraclasse 0,72 - 0,97). Uma modelagem 3D de imagens padrões de cine RMC foi capaz de identificar os indivíduos do estudo com função diastólica reduzida e mostrou uma boa reprodutibilidade, sugerindo ter potencial na avaliação rotineira da função diastólica por RMC.

  3. Mass Spectrometry and Fourier Transform Infrared Spectroscopy for Analysis of Biological Materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Timothy J.

    Time-of-flight mass spectrometry along with statistical analysis was utilized to study metabolic profiles among rats fed resistant starch (RS) diets. Fischer 344 rats were fed four starch diets consisting of 55% (w/w, dbs) starch. A control starch diet consisting of corn starch was compared against three RS diets. The RS diets were high-amylose corn starch (HA7), HA7 chemically modified with octenyl succinic anhydride, and stearic-acid-complexed HA7 starch. A subgroup received antibiotic treatment to determine if perturbations in the gut microbiome were long lasting. A second subgroup was treated with azoxymethane (AOM), a carcinogen. At the end of the eight weekmore » study, cecal and distal-colon contents samples were collected from the sacrificed rats. Metabolites were extracted from cecal and distal colon samples into acetonitrile. The extracts were then analyzed on an accurate-mass time-of-flight mass spectrometer to obtain their metabolic profile. The data were analyzed using partial least-squares discriminant analysis (PLS-DA). The PLS-DA analysis utilized a training set and verification set to classify samples within diet and treatment groups. PLS-DA could reliably differentiate the diet treatments for both cecal and distal colon samples. The PLS-DA analyses of the antibiotic and no antibiotic treated subgroups were well classified for cecal samples and modestly separated for distal-colon samples. PLS-DA analysis had limited success separating distal colon samples for rats given AOM from those not treated; the cecal samples from AOM had very poor classification. Mass spectrometry profiling coupled with PLS-DA can readily classify metabolite differences among rats given RS diets.« less

  4. Contribution to the scintillation detection optimization in double phase detectors for direct detection of dark matter

    NASA Astrophysics Data System (ADS)

    Balan, Catalin

    Na ultima decada, foram feitos grandes progressos no desenvolvimento dos detetores de detecao direta das particulas que constituem a materia negra. Com estrategias do aumento gradual do volume do alvo e, simultaneamente, de reducao dos niveis de fundo, a experiencia XENON obteve resultados muito bons e perspetivas promissoras para a detecao de materia negra. Tarefas relativas a analise de dados experimentais adquiridos com o detetor de dupla fase em uso, assim como as simulacoes do campo eletrico, desenvolvimento, montagem e testes para o proximo detetor XENON1T, assim como a participacao regular na manutencao geral e monitorizacao do prototipo atual XENON100 no LNGS, constituiram o plano de trabalhos para as atividades de investigacao do presente doutoramento e a minha contribuicao para a otimizacao da detecao de cintilacao nos detetores da experiencia XENON. A necessidade de alcancar niveis elevados de sensibilidade, requer inovacao em todos os aspetos fisicos do detetor, assim como a reducao de todas as fontes de radioatividade que contribuem para o fundo. O modo mais indicado de operacao para os detetores com enchimento a Xe no estado liquido e gasoso envolve a medicao da cintilacao primaria e da secundaria provenientes da interacao das particulas no Xe liquido. A razao entre estes dois sinais permite diferenciar claramente a maior parte dos eventos correspondentes as fundo dos eventos correspondentes a WIMPs. Deste modo, a leitura dos sinais correspondentes a cintilacao e de extrema importancia. A amplitude do sinal de cintilacao antes dos fotossensores e maximizada atraves da otimizacao de varios parametros, tais como a geometria do alvo do detetor, a transparencia das grelhas dos eletrodos, a uniformidade do ganho em cintilacao secundaria e a utilizacao de material reflectivo para cobrir as superficies que nao sao fotossensiveis.

  5. Three-dimensional graphene networks as a new substrate for immobilization of laccase and dopamine and its application in glucose/O2 biofuel cell.

    PubMed

    Zhang, Yijia; Chu, Mi; Yang, Lu; Tan, Yueming; Deng, Wenfang; Ma, Ming; Su, Xiaoli; Xie, Qingji

    2014-08-13

    We report here three-dimensional graphene networks (3D-GNs) as a novel substrate for the immobilization of laccase (Lac) and dopamine (DA) and its application in glucose/O2 biofuel cell. 3D-GNs were synthesized with an Ni(2+)-exchange/KOH activation combination method using a 732-type sulfonic acid ion-exchange resin as the carbon precursor. The 3D-GNs exhibited an interconnected network structure and a high specific surface area. DA was noncovalently functionalized on the surface of 3D-GNs with 3,4,9,10-perylene tetracarboxylic acid (PTCA) as a bridge and used as a novel immobilized mediating system for Lac-based bioelectrocatalytic reduction of oxygen. The 3D-GNs-PTCA-DA nanocomposite modified glassy carbon electrode (GCE) showed stable and well-defined redox current peaks for the catechol/o-quinone redox couple. Due to the mediated electron transfer by the 3D-GNs-PTCA-DA nanocomposite, the Nafion/Lac/3D-GNs-PTCA-DA/GCE exhibited high catalytic activity for oxygen reduction. The 3D-GNs are proven to be a better substrate for Lac and its mediator immobilization than 2D graphene nanosheets (2D-GNs) due to the interconnected network structure and high specific surface area of 3D-GNs. A glucose/O2 fuel cell using Nafion/Lac/3D-GNs-PTCA-DA/GCE as the cathode and Nafion/glucose oxidase/ferrocence/3D-GNs/GCE as the anode can output a maximum power density of 112 μW cm(-2) and a short-circuit current density of 0.96 mA cm(-2). This work may be helpful for exploiting the popular 3D-GNs as an efficient electrode material for many other biotechnology applications.

  6. Effect of charge and molecular weight on the functionality of gelatin carriers for corneal endothelial cell therapy.

    PubMed

    Lai, Jui-Yang; Lu, Pei-Lin; Chen, Ko-Hua; Tabata, Yasuhiko; Hsiue, Ging-Ho

    2006-06-01

    Cell transplantation strategies usually involve the use of supporting carrier materials because of the soft and fragile nature of these grafts. In this work, a cell-adhesive gelatin hydrogel carrier was fabricated to deliver cultivated human corneal endothelial cell (HCEC) sheets, which were harvested from thermo-responsive poly(N-isopropylacrylamide) (PNIPAAm)-grafted culture surfaces. The carrier disks, consisting of gelatins with a different isoelectric point (IEP = 5.0 and 9.0) and a molecular weight (MW) ranging from 3 to 100 kDa, were subjected to 16.6 kGy gamma irradiation for sterilization. The effect of IEP and MW of the raw gelatins (i.e., before irradiation) on the functionality of sterilized disks was studied by determinations of mechanical property, water content, dissolution degree, and cytocompatibility. Irrespective of the IEP of raw gelatin, hydrogel disks prepared with high MW (100 kDa) exhibited a greater tensile strength, lower water content, and slower dissolution rate than those made of low MW gelatin (8 and 3 kDa). From the investigation of cellular responses to the disks, the negatively charged gelatin (IEP = 5.0) groups were more cytocompatible when compared with their positively charged counterparts (IEP = 9.0) at the same MW (100 kDa). Additionally, in the negatively charged gelatin groups, only a slight increase in pro-inflammatory cytokine expression was observed with increasing MW of gelatin from 3 to 100 kDa. It is concluded that the gamma-sterilized hydrogel disks made from raw gelatins (IEP = 5.0, MW = 100 kDa) with appropriate dissolution degree and acceptable cytocompatibility are capable of providing stable mechanical support, making these carriers promising candidates for intraocular delivery of cultivated HCEC sheets.

  7. A multidimensional design of charge transfer interfaces via D-A-D linking fashion for electrophysiological sensing of neurotransmitters.

    PubMed

    Liu, He; Liu, Chaoyi; Gu, Yue; Li, Cong; Yan, Xiaoyi; Zhang, Tingting; Lu, Nannan; Zheng, Bo; Li, Yaru; Zhang, Zhiquan; Yang, Ming

    2018-01-15

    Donor-Acceptor (D-A) structure like host-guest pair serves as an organic charge-transfer (C-T) material with pregnant electrochemical and photochemical properties. Phenothiazine, a conjugated nitrogen-sulfur heterocyclic compound with broad pharmaceutical profile, is a strong electron donating system and applied in the synthesis of various classic antipsychotic drugs. In this proposal, a novel D-A molecule, 2,3-bis(4-(10H-phenothiazin-10-yl)phenyl)fumaronitrile (PTBFN), containig a diphenylfumaronitrile as the electrophilic central core and two phenothiazines as the peripheral electron donor functional groups is first designed and synthesized. Subsequently, the C-T layer based on the PTBFN polymer, poly(PTBFN), is obtained via a straightforward electrochemical method and used as an efficient electrocatalyst for dopamine (DA) detection. The logarithm of oxidation peak currents present an outstanding linear response to that of the DA concentration varying from 0.005 to 350μM with a detection limit down to 0.70nM, wherein the interferences of uric acid (UA) and ascorbic acid (AA) could be eliminated effectively. Moreover, the biosensor displays decent stability, excellent selectivity for different interfering compounds and applicability in real samples analysis. The favorable sensing performance suggests that the nontrivial D-A architecture is one of the promising bioaffinity catalysts for electrocatalysis and expected to provide wider application potential for biosensing construction and medical diagnostics. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anheier, Norman C.; Cannon, Bret D.; Martinez, Alonzo

    The International Atomic Energy Agency’s (IAEA’s) long-term research and development plan calls for more cost-effective and efficient safeguard methods to detect and deter misuse of gaseous centrifuge enrichment plants (GCEPs). The IAEA’s current safeguards approaches at GCEPs are based on a combination of routine and random inspections that include environmental sampling and destructive assay (DA) sample collection from UF6 in-process material and selected cylinders. Samples are then shipped offsite for subsequent laboratory analysis. In this paper, a new DA sample collection and onsite analysis approach that could help to meet challenges in transportation and chain of custody for UF6 DAmore » samples is introduced. This approach uses a handheld sampler concept and a Laser Ablation, Laser Absorbance Spectrometry (LAARS) analysis instrument, both currently under development at the Pacific Northwest National Laboratory. A LAARS analysis instrument could be temporarily or permanently deployed in the IAEA control room of the facility, in the IAEA data acquisition cabinet, for example. The handheld PNNL DA sampler design collects and stabilizes a much smaller DA sample mass compared to current sampling methods. The significantly lower uranium mass reduces the sample radioactivity and the stabilization approach diminishes the risk of uranium and hydrogen fluoride release. These attributes enable safe sample handling needed during onsite LAARS assay and may help ease shipping challenges for samples to be processed at the IAEA’s offsite laboratory. The LAARS and DA sampler implementation concepts will be described and preliminary technical viability results presented.« less

  9. The Indosinian orogeny: A perspective from sedimentary archives of north Vietnam

    NASA Astrophysics Data System (ADS)

    Rossignol, Camille; Bourquin, Sylvie; Hallot, Erwan; Poujol, Marc; Dabard, Marie-Pierre; Martini, Rossana; Villeneuve, Michel; Cornée, Jean-Jacques; Brayard, Arnaud; Roger, Françoise

    2018-06-01

    The Triassic stratigraphic framework for the Song Da and the Sam Nua basins, north Vietnam, suffers important discrepancies regarding both the depositional environments and ages of the main formations they contain. Using sedimentological analyses and dating (foraminifer biostratigraphy and U-Pb dating on detrital zircon), we provide an improved stratigraphic framework for both basins. A striking feature in the Song Da Basin, located on the southern margin of the South China Block, is the diachronous deposition, over a basal unconformity, of terrestrial and marine deposits. The sedimentary succession of the Song Da Basin points to a foreland setting during the late Early to the Middle Triassic, which contrasts with the commonly interpreted rift setting. On the northern margin of the Indochina Block, the Sam Nua basin recorded the activity of a proximal magmatic arc during the late Permian up to the Anisian. This arc resulted from the subduction of a southward dipping oceanic slab that separated the South China block from the Indochina block. During the Middle to the Late Triassic, the Song Da and Sam Nua basins underwent erosion that led to the formation of a major unconformity, resulting from the erosion of the Middle Triassic Indosinian mountain belt, built after an ongoing continental collision between the South China and the Indochina blocks. Later, during the Late Triassic, as syn- to post-orogenic foreland basins in a terrestrial setting, the Song Da and Sam Nua basins experienced the deposition of very coarse detrital material representing products of the mountain belt erosion.

  10. Lipid mobilising factors specifically associated with cancer cachexia.

    PubMed Central

    Beck, S. A.; Tisdale, M. J.

    1991-01-01

    Both urine and plasma from mice and humans with cancer cachexia have been shown to contain higher levels of lipid mobilising activity than normal controls, even after acute starvation. There was no significant increase in the urinary lipid mobilising activity of either mice or humans after acute starvation, suggesting that the material in the cachectic situation was probably not due to an elevation of hormones normally associated with the catabolic state in starvation. Further characterisation of the lipid mobilising activity in the urine of cachectic mice using Sephadex G50 exclusion chromatography showed four distinct peaks of activity of apparent molecular weights of greater than 20, 3, 1.5 and less than 0.7 kDa. No comparable peaks of activity were found in the urine of a non tumour-bearing mouse. The high molecular weight activity was probably formed by aggregation of low molecular weight material, since treatment with 0.5 M NaCl caused dissociation to material with a broad spectrum of molecular weights between 3 and 0.7 kDa. Lipolytic species of similar molecular weights were also found in the urine of cachectic cancer patients, but not in normal urine even after 24 h starvation. The lipid mobilising species may be responsible for catabolism of host adipose tissue in the cachectic state. PMID:2069843

  11. JCoDA: a tool for detecting evolutionary selection.

    PubMed

    Steinway, Steven N; Dannenfelser, Ruth; Laucius, Christopher D; Hayes, James E; Nayak, Sudhir

    2010-05-27

    The incorporation of annotated sequence information from multiple related species in commonly used databases (Ensembl, Flybase, Saccharomyces Genome Database, Wormbase, etc.) has increased dramatically over the last few years. This influx of information has provided a considerable amount of raw material for evaluation of evolutionary relationships. To aid in the process, we have developed JCoDA (Java Codon Delimited Alignment) as a simple-to-use visualization tool for the detection of site specific and regional positive/negative evolutionary selection amongst homologous coding sequences. JCoDA accepts user-inputted unaligned or pre-aligned coding sequences, performs a codon-delimited alignment using ClustalW, and determines the dN/dS calculations using PAML (Phylogenetic Analysis Using Maximum Likelihood, yn00 and codeml) in order to identify regions and sites under evolutionary selection. The JCoDA package includes a graphical interface for Phylip (Phylogeny Inference Package) to generate phylogenetic trees, manages formatting of all required file types, and streamlines passage of information between underlying programs. The raw data are output to user configurable graphs with sliding window options for straightforward visualization of pairwise or gene family comparisons. Additionally, codon-delimited alignments are output in a variety of common formats and all dN/dS calculations can be output in comma-separated value (CSV) format for downstream analysis. To illustrate the types of analyses that are facilitated by JCoDA, we have taken advantage of the well studied sex determination pathway in nematodes as well as the extensive sequence information available to identify genes under positive selection, examples of regional positive selection, and differences in selection based on the role of genes in the sex determination pathway. JCoDA is a configurable, open source, user-friendly visualization tool for performing evolutionary analysis on homologous coding sequences. JCoDA can be used to rapidly screen for genes and regions of genes under selection using PAML. It can be freely downloaded at http://www.tcnj.edu/~nayaklab/jcoda.

  12. JCoDA: a tool for detecting evolutionary selection

    PubMed Central

    2010-01-01

    Background The incorporation of annotated sequence information from multiple related species in commonly used databases (Ensembl, Flybase, Saccharomyces Genome Database, Wormbase, etc.) has increased dramatically over the last few years. This influx of information has provided a considerable amount of raw material for evaluation of evolutionary relationships. To aid in the process, we have developed JCoDA (Java Codon Delimited Alignment) as a simple-to-use visualization tool for the detection of site specific and regional positive/negative evolutionary selection amongst homologous coding sequences. Results JCoDA accepts user-inputted unaligned or pre-aligned coding sequences, performs a codon-delimited alignment using ClustalW, and determines the dN/dS calculations using PAML (Phylogenetic Analysis Using Maximum Likelihood, yn00 and codeml) in order to identify regions and sites under evolutionary selection. The JCoDA package includes a graphical interface for Phylip (Phylogeny Inference Package) to generate phylogenetic trees, manages formatting of all required file types, and streamlines passage of information between underlying programs. The raw data are output to user configurable graphs with sliding window options for straightforward visualization of pairwise or gene family comparisons. Additionally, codon-delimited alignments are output in a variety of common formats and all dN/dS calculations can be output in comma-separated value (CSV) format for downstream analysis. To illustrate the types of analyses that are facilitated by JCoDA, we have taken advantage of the well studied sex determination pathway in nematodes as well as the extensive sequence information available to identify genes under positive selection, examples of regional positive selection, and differences in selection based on the role of genes in the sex determination pathway. Conclusions JCoDA is a configurable, open source, user-friendly visualization tool for performing evolutionary analysis on homologous coding sequences. JCoDA can be used to rapidly screen for genes and regions of genes under selection using PAML. It can be freely downloaded at http://www.tcnj.edu/~nayaklab/jcoda. PMID:20507581

  13. Cell-type-specific profiling of protein-DNA interactions without cell isolation using targeted DamID with next-generation sequencing.

    PubMed

    Marshall, Owen J; Southall, Tony D; Cheetham, Seth W; Brand, Andrea H

    2016-09-01

    This protocol is an extension to: Nat. Protoc. 2, 1467-1478 (2007); doi:10.1038/nprot.2007.148; published online 7 June 2007The ability to profile transcription and chromatin binding in a cell-type-specific manner is a powerful aid to understanding cell-fate specification and cellular function in multicellular organisms. We recently developed targeted DamID (TaDa) to enable genome-wide, cell-type-specific profiling of DNA- and chromatin-binding proteins in vivo without cell isolation. As a protocol extension, this article describes substantial modifications to an existing protocol, and it offers additional applications. TaDa builds upon DamID, a technique for detecting genome-wide DNA-binding profiles of proteins, by coupling it with the GAL4 system in Drosophila to enable both temporal and spatial resolution. TaDa ensures that Dam-fusion proteins are expressed at very low levels, thus avoiding toxicity and potential artifacts from overexpression. The modifications to the core DamID technique presented here also increase the speed of sample processing and throughput, and adapt the method to next-generation sequencing technology. TaDa is robust, reproducible and highly sensitive. Compared with other methods for cell-type-specific profiling, the technique requires no cell-sorting, cross-linking or antisera, and binding profiles can be generated from as few as 10,000 total induced cells. By profiling the genome-wide binding of RNA polymerase II (Pol II), TaDa can also identify transcribed genes in a cell-type-specific manner. Here we describe a detailed protocol for carrying out TaDa experiments and preparing the material for next-generation sequencing. Although we developed TaDa in Drosophila, it should be easily adapted to other organisms with an inducible expression system. Once transgenic animals are obtained, the entire experimental procedure-from collecting tissue samples to generating sequencing libraries-can be accomplished within 5 d.

  14. An ultrasensitive lysozyme chemiluminescence biosensor based on surface molecular imprinting using ionic liquid modified magnetic graphene oxide/β-cyclodextrin as supporting material.

    PubMed

    Duan, Huimin; Wang, Xiaojiao; Wang, Yanhui; Sun, Yuanling; Li, Jianbo; Luo, Chuannan

    2016-04-28

    In this work, ionic liquid modified Fe3O4@dopamine/graphene oxide/β-cyclodextrin (ILs-Fe3O4@DA/GO/β-CD) was used as supporting material to synthesize surface molecularly imprinted polymer (SMIP) which then was introduced into chemiluminescence (CL) to achieve an ultrasensitive and selective biosensor for determination of lysozyme (Lys). ILs and β-CD was applied to provide multiple binding sites to prepare Lys SMIP and Fe3O4@DA was designed to make the product separate easily and prevent the aggregation of GO which could improve absorption capacity for its large specific surface area. The ILs-Fe3O4@DA/GO/β-CD-SMIP showed high adsorption capacity (Q = 101 mg/g) to Lys in the adsorption isotherm assays. The adsorption equilibrium was reached within 10 min for all the concentrations, attributing to the binding sites situated exclusively at the surface, and the adsorption model followed Langmuir isotherm. Under the suitable CL conditions, the proposed biosensor could response Lys linearly in the range of 1.0 × 10(-9)-8.0 × 10(-8) mg/mL with a detection limit of 3.0 × 10(-10) mg/mL. When used in practical samples in determination of Lys, the efficient biosensor exhibited excellent result with the recoveries ranging from 94% to 112%. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Standoff detection of chemical and biological threats using laser-induced breakdown spectroscopy.

    PubMed

    Gottfried, Jennifer L; De Lucia, Frank C; Munson, Chase A; Miziolek, Andrzej W

    2008-04-01

    Laser-induced breakdown spectroscopy (LIBS) is a promising technique for real-time chemical and biological warfare agent detection in the field. We have demonstrated the detection and discrimination of the biological warfare agent surrogates Bacillus subtilis (BG) (2% false negatives, 0% false positives) and ovalbumin (0% false negatives, 1% false positives) at 20 meters using standoff laser-induced breakdown spectroscopy (ST-LIBS) and linear correlation. Unknown interferent samples (not included in the model), samples on different substrates, and mixtures of BG and Arizona road dust have been classified with reasonable success using partial least squares discriminant analysis (PLS-DA). A few of the samples tested such as the soot (not included in the model) and the 25% BG:75% dust mixture resulted in a significant number of false positives or false negatives, respectively. Our preliminary results indicate that while LIBS is able to discriminate biomaterials with similar elemental compositions at standoff distances based on differences in key intensity ratios, further work is needed to reduce the number of false positives/negatives by refining the PLS-DA model to include a sufficient range of material classes and carefully selecting a detection threshold. In addition, we have demonstrated that LIBS can distinguish five different organophosphate nerve agent simulants at 20 meters, despite their similar stoichiometric formulas. Finally, a combined PLS-DA model for chemical, biological, and explosives detection using a single ST-LIBS sensor has been developed in order to demonstrate the potential of standoff LIBS for universal hazardous materials detection.

  16. New denture adhesive containing miconazole nitrate polymeric microparticles: Antifungal, adhesive force and toxicity properties.

    PubMed

    Cartagena, Andrés Felipe; Esmerino, Luís Antonio; Polak-Junior, Rogerio; Olivieri Parreiras, Sibelli; Domingos Michél, Milton; Farago, Paulo Vitor; Campanha, Nara Hellen

    2017-02-01

    The purpose of this study was to develop a new oral drug delivery system by incorporating polymeric miconazole nitrate (MN) microparticles on an experimental antifungal denture adhesive (DA). Spray drying Eudragit L-100 (E) and Gantrez MS-955 (G) MN-microparticles were incorporated in DA. DAE1, DAG1, DAEG1, DAE2, DAG2, DAEG2 groups were obtained from the combination of polymers used in MN-microparticles (E, G and EG) and concentration of MN into DA (1, for 1% and 2, for 2%). DA with 2% pure MN (DAM) and DA without microparticles or drug (DACT) were both control groups. All groups were evaluated to determine microbiological assay, adhesive force and toxicity. Minimum inhibitory concentration (MIC) against Candida albicans was performed by broth micro-dilution and agar dilution methods in extract of DAs and conventional gel form (Daktarin ® ). Adhesive load testing was made between acrylic resin samples on a universal testing machine after immersion in water. The toxicity of several dilutions of DAs was performed with Artemia salina bioassay after 24 and 48h. Data of adhesive force were evaluated with two-way ANOVA and Bonferroni tests (α=0.05). The concentration required to kill 50% (LC50) was determined using the Provit analysis. DA with polymeric microparticles and pure drug presented MIC between 1.25-5μg/mL similar to MIC values of DAM. DAEG2, DAEG1, DAG20 showed the most actives against C. albicans. The best adhesive properties were exhibited by DAEG2, consisting of high initial adhesive force which was maintained for up to 6h. The extracts of all DA presented low or not toxicity at 24 and 48h. DA containing 2% of MN loaded in microparticles made by Gantrez MS-955 alone or combined with Eudragit L-100 produce effective antifungal activity, good adhesive force, and no toxicity effect being a promising therapeutics for removable denture wearers affected by denture stomatitis. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  17. Improved radiocarbon dating for contaminated archaeological bone collagen, silk, wool and hair samples via cross-flow nanofiltrated amino acids.

    PubMed

    Boudin, Mathieu; Boeckx, Pascal; Vandenabeele, Peter; Van Strydonck, Mark

    2013-09-30

    Radiocarbon dating and stable isotope analyses of bone collagen, wool, hair and silk contaminated with extraneous carbon (e.g. humic substances) does not yield reliable results if these materials are pre-treated using conventional methods. A cross-flow nanofiltration method was developed that can be applied to various protein materials like collagen, hair, silk, wool and leather, and should be able to remove low-molecular and high-molecular weight contaminants. To avoid extraneous carbon contamination via the filter a ceramic filter (molecular weight cut-off of 200 Da) was used. The amino acids, released by hot acid hydrolysis of the protein material, were collected in the permeate and contaminants in the retentate (>200 Da). (14)C-dating results for various contaminated archaeological samples were compared for bulk material (pre-treated with the conventional methods) and for cross-flow nanofiltrated amino acids (permeate) originating from the same samples. Contamination and quality control of (14)C dates of bulk and permeate samples were obtained by measuring C:N ratios, fluorescence spectra, and δ(13)C and δ(15)N values of the samples. Cross-flow nanofiltration decreases the C:N ratio which means that contaminants have been removed. Cross-flow nanofiltration clearly improved sample quality and (14)C results. It is a quick and non-labor-intensive technique and can easily be implemented in any (14)C and stable isotope laboratory for routine sample pre-treatment analyses. Copyright © 2013 John Wiley & Sons, Ltd.

  18. A virus capsid-like nanocompartment that stores iron and protects bacteria from oxidative stress.

    PubMed

    McHugh, Colleen A; Fontana, Juan; Nemecek, Daniel; Cheng, Naiqian; Aksyuk, Anastasia A; Heymann, J Bernard; Winkler, Dennis C; Lam, Alan S; Wall, Joseph S; Steven, Alasdair C; Hoiczyk, Egbert

    2014-09-01

    Living cells compartmentalize materials and enzymatic reactions to increase metabolic efficiency. While eukaryotes use membrane-bound organelles, bacteria and archaea rely primarily on protein-bound nanocompartments. Encapsulins constitute a class of nanocompartments widespread in bacteria and archaea whose functions have hitherto been unclear. Here, we characterize the encapsulin nanocompartment from Myxococcus xanthus, which consists of a shell protein (EncA, 32.5 kDa) and three internal proteins (EncB, 17 kDa; EncC, 13 kDa; EncD, 11 kDa). Using cryo-electron microscopy, we determined that EncA self-assembles into an icosahedral shell 32 nm in diameter (26 nm internal diameter), built from 180 subunits with the fold first observed in bacteriophage HK97 capsid. The internal proteins, of which EncB and EncC have ferritin-like domains, attach to its inner surface. Native nanocompartments have dense iron-rich cores. Functionally, they resemble ferritins, cage-like iron storage proteins, but with a massively greater capacity (~30,000 iron atoms versus ~3,000 in ferritin). Physiological data reveal that few nanocompartments are assembled during vegetative growth, but they increase fivefold upon starvation, protecting cells from oxidative stress through iron sequestration. © 2014 The Authors.

  19. Effect of wet oxidation on the fingerprints of polymeric substances from an activated sludge.

    PubMed

    Urrea, José Luis; Collado, Sergio; Oulego, Paula; Díaz, Mario

    2016-11-15

    Thermal pre-treatments of activated sludge involve the release of a high amount of polymeric substances into the bulk medium. The molecular size of these polymers will largely define the subsequent biological treatment of the liquid effluent generated. In this work, the effects of wet oxidation treatment (WO) on the fingerprints of the polymeric substances which compose the activated sludge, were analysed. For a better understanding of these transformations, the sludge was separated into its main fractions: soluble microbial products (SMP), loosely bound extracellular polymeric substances (LB-EPS), tightly bound extracellular polymeric substances (TB-EPS) and naked cells, and then each one was subjected to WO separately (190 °C and 65 bar), determining the fingerprints evolution by size exclusion technique. Results revealed a fast degradation of larger molecules (over 500 kDa) during the first minutes of treatment (40 min). WO also increases the absorptive properties of proteins (especially for 30 kDa), which is possibly due to the hydroxylation of phenylalanine amino acids in their structure. WO of naked cells involved the formation of molecules between 23 and 190 kDa, which are related to the release of cytoplasmic polymers, and more hydrophobic polymers, probably from the cell membrane. The results allowed to establish a relationship between the location of polymeric material and its facility to become oxidised; thus, the more internal the polymeric material in the cell, the easier its oxidation. When working directly with the raw sludge, hydrolysis mechanisms played a key role during the starting period. Once a high degree of solubilisation was reached, the molecules were rapidly oxidised into other compounds with refractory characteristics. The final effluent after WO showed almost 90% of low molecular weight solubilised substances (0-35 kDa). Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. A bone tissue engineering strategy based on starch scaffolds and bone marrow cells cultured in a flow perfusion bioreactor

    NASA Astrophysics Data System (ADS)

    Gomes, Maria Manuela Estima

    A Engenharia de Tecidos e uma area cientifica em continua expansao. Os desenvolvimentos conseguidos por esta area tem contribuido significativamente para diversos avancos no campo da Medicina Regenerativa. Esta ciencia interdisciplinar combina os conhecimentos de diversas outras areas, tao distintas como a Engenharia de Materiais e a Biologia, com o objectivo de desenvolver substitutos sinteticos para tecidos humanos. Para se atingir este objectivo utilizam-se, de uma forma generica, combinacoes especificas de celulas e de um material de suporte tridimensional com propriedades adequadas, gerando um material hibrido cujas caracteristicas podem ainda ser moduladas atraves do sistema de cultura usado. A presente tese e centrada no desenvolvimento de estrategias de engenharia de tecido osseo baseadas na cultura in vitro de celulas previamente "semeadas" num suporte tridimensional ("scaffold"). Esta estrategia permite que as celulas adiram ao suporte, proliferem e segreguem matriz extracelular especifica do tecido osseo, ate se obter um substituto artificial funcional com caracteristicas do tecido original, que pode finalmente ser transplantado para tratar o defeito em causa. Para que uma estrategia deste tipo seja bem sucedida, pelo menos tres componentes fundamentais devem ser cuidadosamente estudados: o material de suporte (scaffold), as celulas a usar e o sistema de cultura in vitro. Dai que os principais objectivos desta tese estejam relacionados com estes tres aspectos, nomeadamente: • Desenvolvimento de scaffolds biodegradaveis a partir de polimeros a base de amido de milho que induzam a adesao e proliferacao celular e que apresentem propriedades adequadas, tais como a porosidade e interconectividade entre poros, de forma a proporcionar um ambiente que favoreca o desenvolvimento in vitro de um material hibrido com caracteristicas similares ao osso humano. • Estudo da utilizacao de celulas da medula ossea como uma potencial fonte de celulas para engenharia do tecido osseo, uma vez que estas celulas podem ser facilmente recolhidas do proprio paciente a tratar por metodos nao-invasivos (bioppsia) e em quantidades suficientes. Alem disso, tratando-se de uma fonte de celulas autologas (obtidas do proprio paciente) permitem evitar os riscos de transmissao de doencas contagiosas e/ou de rejeicao pelo sistema imunologico. • Estudo da influencia das condicoes de cultura in vitro geradas por um bioreactor de perfusao (em comparacao com os metodos tradicionais de cultura em condicoes estaticas) no desenvolvimento dos materiais hibridos, compostos pelas celulas e scaffolds, assim como as interaccoes do ambiente proporcionado por este sistema de cultura com as diferentes estruturas/arquitecturas e porosidades dos scaffolds utilizados. Estes objectivos convergem para o objectivo geral desta tese que consistiu no desenvolvimento de uma terapia de engenharia do tecido osseo alternativa as existentes e com potencial para vir a ser posteriormente utilizada na pratica clinica. Este objectivo foi avaliado atraves do estudo da funcionalidade dos materiais hibridos obtidos em diferentes condicoes de cultura in vitro (e utilizando diferentes scaffolds), partindo do principio que o sistema de perfusao poderia eventualmente superar as limitacoes de difusao tipicas dos sistema de cultura estatica e simultaneamente proporcionar estimulos mecânicos as celulas, semelhantes aos encontrados em condicoes fisiologicas. (Abstract shortened by ProQuest.).

  1. Multipurpose Corrosion Inhibitors for Aerospace Materials in Naval Environments

    DTIC Science & Technology

    1987-06-04

    Figure 1. The (da/dN i vs. AK plot is typica: of tr " curves obtained. The abbreviations MA. CTM and DNBM stand for moist air. dichromate - tellurate ...plastic deformation which occurs by the movement of dislocations to the surface (19) is the precursor of the cracking process in metals. Since

  2. 40 CFR 60.41Da - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., reconstructed, or modified before March 1, 2005, means a 24-hour period during which fossil fuel is combusted in... CFR 52.21 or under 40 CFR 51.18 and 51.24. Fossil fuel means natural gas, petroleum, coal, and any form of solid, liquid, or gaseous fuel derived from such material for the purpose of creating useful...

  3. 40 CFR 60.41Da - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., reconstructed, or modified before March 1, 2005, means a 24-hour period during which fossil fuel is combusted in... permit requirements established under 40 CFR 52.21 or under 40 CFR 51.18 and 51.24. Fossil fuel means natural gas, petroleum, coal, and any form of solid, liquid, or gaseous fuel derived from such material...

  4. 40 CFR 60.41Da - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., reconstructed, or modified before March 1, 2005, means a 24-hour period during which fossil fuel is combusted in... CFR 52.21 or under 40 CFR 51.18 and 51.24. Fossil fuel means natural gas, petroleum, coal, and any form of solid, liquid, or gaseous fuel derived from such material for the purpose of creating useful...

  5. 78 FR 38265 - Wireline Competition Bureau Adds Two New Discussion Topics to Connect America Cost Model Virtual...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-26

    ... information from parties that post material in the virtual workshop will be publicly available for inspection... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 54 [WC Docket No. 10-90; DA 13-1396] Wireline...: Federal Communications Commission. ACTION: Proposed rule. SUMMARY: In this document, the Wireline...

  6. Graphene Quantum Dots-based Photoluminescent Sensor: A Multifunctional Composite for Pesticide Detection.

    PubMed

    Zor, Erhan; Morales-Narváez, Eden; Zamora-Gálvez, Alejandro; Bingol, Haluk; Ersoz, Mustafa; Merkoçi, Arben

    2015-09-16

    Due to their size and difficulty to obtain, cost/effective biological or synthetic receptors (e.g., antibodies or aptamers, respectively), organic toxic compounds (e.g., less than 1 kDa) are generally challenging to detect using simple platforms such as biosensors. This study reports on the synthesis and characterization of a novel multifunctional composite material, magnetic silica beads/graphene quantum dots/molecularly imprinted polypyrrole (mSGP). mSGP is engineered to specifically and effectively capture and signal small molecules due to the synergy among chemical, magnetic, and optical properties combined with molecular imprinting of tributyltin (291 Da), a hazardous compound, selected as a model analyte. Magnetic and selective properties of the mSGP composite can be exploited to capture and preconcentrate the analyte onto its surface, and its photoluminescent graphene quantum dots, which are quenched upon analyte recognition, are used to interrogate the presence of the contaminant. This multifunctional material enables a rapid, simple and sensitive platform for small molecule detection, even in complex mediums such as seawater, without any sample treatment.

  7. Annotated type catalogue of the Bulimulidae (Mollusca, Gastropoda, Orthalicoidea) in the Natural History Museum, London

    PubMed Central

    Breure, Abraham S.H.; Ablett, Jonathan D.

    2014-01-01

    Abstract The type status is described of 404 taxa classified within the family Bulimulidae (superfamily Orthalicoidea) and kept in the London museum. Lectotypes are designated for Bulimus aurifluus Pfeiffer, 1857; Otostomus bartletti H. Adams, 1867; Helix cactorum d’Orbigny, 1835; Bulimus caliginosus Reeve, 1849; Bulimus chemnitzioides Forbes, 1850; Bulimus cinereus Reeve, 1849; Helix cora d’Orbigny, 1835; Bulimus fallax Pfeiffer, 1853; Bulimus felix Pfeiffer, 1862; Bulimus fontainii d’Orbigny, 1838; Bulimus fourmiersi d’Orbigny, 1837; Bulimus (Mesembrinus) gealei H. Adams, 1867; Bulimus gruneri Pfeiffer, 1846; Bulimus humboldtii Reeve, 1849; Helix hygrohylaea d’Orbigny, 1835; Bulimus jussieui Pfeiffer, 1846; Bulimulus (Drymaeus) binominis lascellianus E.A. Smith, 1895; Helix lichnorum d’Orbigny, 1835; Bulimulus (Drymaeus) lucidus da Costa, 1898; Bulimus luridus Pfeiffer, 1863; Bulimus meleagris Pfeiffer, 1853; Bulimus monachus Pfeiffer, 1857; Bulimus montagnei d’Orbigny, 1837; Helix montivaga d’Orbigny, 1835; Bulimus muliebris Reeve, 1849; Bulimus nigrofasciatus Pfeiffer in Philippi 1846; Bulimus nitelinus Reeve, 1849; Helix oreades d’Orbigny, 1835; Helix polymorpha d’Orbigny, 1835; Bulimus praetextus Reeve, 1849; Bulinus proteus Broderip, 1832; Bulimus rusticellus Morelet, 1860; Helix sporadica d’Orbigny, 1835; Bulimus sulphureus Pfeiffer, 1857; Helix thamnoica var. marmorata d’Orbigny, 1835; Bulinus translucens Broderip in Broderip and Sowerby I 1832; Helix trichoda d’Orbigny, 1835; Bulinus ustulatus Sowerby I, 1833; Bulimus voithianus Pfeiffer, 1847; Bulimus yungasensis d’Orbigny, 1837. The type status of the following taxa is changed to lectotype in accordance with Art. 74.6 ICZN: Bulimulus (Drymaeus) caucaensis da Costa, 1898; Drymaeus exoticus da Costa, 1901; Bulimulus (Drymaeus) hidalgoi da Costa, 1898; Bulimulus (Drymaeus) interruptus Preston, 1909; Bulimulus (Drymaeus) inusitatus Fulton, 1900; Bulimulus latecolumellaris Preston, 1909; Bulimus (Otostomus) napo Angas, 1878; Drymaeus notabilis da Costa, 1906; Drymaeus notatus da Costa, 1906; Bulimulus (Drymaeus) nubilus Preston, 1903; Drymaeus obliquistriatus da Costa, 1901; Bulimus (Drymaeus) ochrocheilus E.A. Smith, 1877; Bulimus (Drymaeus) orthostoma E.A. Smith, 1877; Drymaeus expansus perenensis da Costa, 1901; Bulimulus pergracilis Rolle, 1904; Bulimulus (Drymaeus) plicatoliratus da Costa, 1898; Drymaeus prestoni da Costa, 1906; Drymaeus punctatus da Costa, 1907; Bulimus (Leptomerus) sanctaeluciae E.A. Smith, 1889; Bulimulus (Drymaeus) selli Preston, 1909; Drymaeus subventricosus da Costa, 1901; Bulimulus (Drymaeus) tigrinus da Costa, 1898; Drymaeus volsus Fulton, 1907; Drymaeus wintlei Finch, 1929; Bulimus zhorquinensis Angas, 1879; Bulimulus (Drymaeus) ziczac da Costa, 1898. The following junior subjective synonyms are established: Bulimus antioquensis Pfeiffer, 1855 = Bulimus baranguillanus Pfeiffer, 1853; Drymaeus bellus da Costa, 1906 = Drymaeus blandi Pilsbry, 1897; Bulimus hachensis Reeve 1850 = Bulimus gruneri Pfeiffer, 1846 = Bulimus columbianus Lea, 1838; Bulimus (Otostomus) lamas Higgins 1868 = Bulimus trujillensis Philippi, 1867; Bulimulus (Drymaeus) binominis lascellianus E.A. Smith, 1895 = Bulimulus (Drymaeus) binominis E.A. Smith, 1895; Drymaeus multispira da Costa, 1904 = Helix torallyi d’Orbigny, 1835; Bulimulus (Drymaeus) plicatoliratus Da Costa, 1898 = Bulimus convexus Pfeiffer, 1855; Bulimus sugillatus Pfeiffer, 1857 = Bulimus rivasii d’Orbigny, 1837; Bulimus meridionalis Reeve 1848 [June] = Bulimus voithianus Pfeiffer, 1847. New combinations are: Bostryx montagnei (d’Orbigny, 1837); Bostryx obliquiportus (da Costa, 1901); Bulimulus heloicus (d’Orbigny, 1835); Drymaeus (Drymaeus) lusorius (Pfeiffer, 1855); Drymaeus (Drymaeus) trigonostomus (Jonas, 1844); Drymaeus (Drymaeus) wintlei Finch, 1929; Drymaeus (Mesembrinus) conicus da Costa, 1907; Kuschelenia (Kuschelenia) culminea culminea (d’Orbigny, 1835); Kuschelenia (Kuschelenia) culmineus edwardsi (Morelet, 1863); Kuschelenia (K.) gayi (Pfeiffer, 1857); Kuschelenia (Kuschelenia) tupacii (d’Orbigny, 1835); Kuschelenia (Vermiculatus) anthisanensis (Pfeiffer, 1853); Kuschelenia (Vermiculatus) aquilus (Reeve, 1848); Kuschelenia (Vermiculatus) bicolor (Sowerby I, 1835); Kuschelenia (Vermiculatus) caliginosus (Reeve, 1849); Kuschelenia (Vermiculatus) cotopaxiensis (Pfeiffer, 1853); Kuschelenia (Vermiculatus) filaris (Pfeiffer, 1853); Kuschelenia (Vermiculatus) ochracea (Morelet, 1863); Kuschelenia (Vermiculatus) petiti (Pfeiffer, 1846); Kuschelenia (Vermiculatus) purpuratus (Reeve, 1849); Kuschelenia (Vermiculatus) quechuarum (Crawford, 1939); Naesiotus cinereus (Reeve, 1849); Naesiotus dentritis (Morelet, 1863); Naesiotus fontainii (d’Orbigny, 1838); Naesiotus orbignyi (Pfeiffer, 1846); Protoglyptus pilosus (Guppy, 1871); Protoglyptus sanctaeluciae (E.A. Smith, 1889). Type material of the following taxa is figured herein for the first time: Bulimus cinereus Reeve, 1849; Bulimus coriaceus Pfeiffer, 1857; Bulimulus laxostylus Rolle, 1904; Bulimus pliculatus Pfeiffer, 1857; Bulimus simpliculus Pfeiffer, 1855. PMID:24715782

  8. Jabuticaba-Induced Endothelium-Independent Vasodilating Effect on Isolated Arteries.

    PubMed

    Andrade, Daniela Medeiros Lobo de; Borges, Leonardo Luis; Torres, Ieda Maria Sapateiro; Conceição, Edemilson Cardoso da; Rocha, Matheus Lavorenti

    2016-09-01

    Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified. To determine the effects of jabuticaba hydroalcoholic extract (JHE) on vascular smooth muscle (VSM) of isolated arteries. Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed. Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL). Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine) hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM). JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect. Embora a jabuticaba apresente importantes efeitos biológicos, suas ações sobre o sistema cardiovascular ainda não foram esclarecidas. Determinar os efeitos do extrato de jabuticaba (EHJ) sobre o músculo liso vascular (MLV) em artérias isoladas. Aortas (sem endotélio) de ratos foram montadas em banho de órgãos isolados para registro de tensão isométrica. Foram verificados o efeito relaxante, a influência dos canais de K+ e das fontes de Ca2+ intra- e extracelular sob a resposta estimulada pelo EHJ. Artérias pré-contraídas com fenilefrina apresentaram relaxamento concentração-dependente (0,380 a 1,92 mg/mL). O tratamento com bloqueadores de canais de K+ (tetraetilamônio, glibenclamida, 4-aminopiridina) prejudicaram o relaxamento pelo EHJ. A contração estimulada com fenilefrina também foi prejudicada pelo tratamento prévio com EHJ. A inibição da Ca2+ATPase do reticulo sarcoplasmático não alterou o relaxamento pelo EHJ. Além disso, o EHJ inibiu a contração causada pelo influxo de Ca2+ estimulado por fenilefrina e KCl (75 mM). O EHJ induz vasodilatação independente do endotélio. Ativação dos canais de K+ e inibição do influxo de Ca2+ através da membrana estão envolvidas no efeito relaxante do EHJ.

  9. Imagens do céu ontem e hoje - um multimídia interativo de astronomia e uma nova exposição no MAST

    NASA Astrophysics Data System (ADS)

    Caretta, C. A.; Lima, F. P.; Requeijo, F.; Vieira, G. G.; Alves, F.; Valente, M. E. A.; de Almeida, R.; de Garcia, G. C.; Quixadá, A. C.

    2003-08-01

    "Imagens do Céu Ontem e Hoje" é o título de uma nova exposição que está sendo inaugurada no Museu de Astronomia e Ciências Afins (MCT), que inclui experimentos interativos, maquetes, réplicas e 8 terminais de computador com um multimídia interativo sobre Astronomia para consulta dos visitantes. O multimídia apresenta um conteúdo bastante extenso, que engloba quase todos os temas em Astronomia, consistindo numa fonte de divulgação e pesquisa para um público que vai das crianças até estudantes universitários. O conteúdo está distribuído em mais de 500 páginas de texto divididas em 4 módulos: "O Universo", "Espectroscopia", "Telescópios" e "Observando o Céu". Cada módulo é subdividido em 5 seções, em média, cada uma iniciada por uma animação que ilustra os temas a serem abordados na seção. Ao final da animação, uma lista de temas é apresentada sob o título "Saiba Mais". Para exemplificar, o módulo "O Universo" contém as seguintes seções: "O Universo visto pelo homem", "Conhecendo o Sistema Solar", "Indo além do Sistema Solar", "Nossa Galáxia, a Via-Láctea" e "Indo mais além, a imensidão do Universo". A seção "Conhecendo o Sistema Solar", por sua vez, tem os seguintes temas: "A origem do Sistema Solar", "O Sol", "Os planetas", "Satélites, asteróides, cometas e outros bichos..." e "O Sistema Solar em números". Cada texto é repleto de imagens, quadros, desenhos, esquemas, etc, além de passatempos ao final de cada seção, incluindo jogos interativos, quadrinhos e curiosidades, que auxiliam o aprendizado de forma divertida. Apresentamos neste trabalho as idéias gerais que permearam a produção da exposição, e uma viagem pelo multimídia para exemplificar sua estrutura e conteúdo. O multimídia será posteriormente disponibilizado para o público externo pela página eletrônica do MAst e/ou por intermédio de uma publicação comercial.

  10. Theater Mental Health Encounter Data (TMHED): Overview of Design and Methods

    DTIC Science & Technology

    2011-11-01

    Tremblino or shakina 0 Depersonalization 0 Insomnia I Hypersomnia I Steep disturbance 0 Short of breath/smothering 0 Dissociative Amnesia 0...Tremblingshaking ~ -0 De~rsonallzation D PsY.chom D SOB/smothering D Dissociative Amnesia D Fat ue /loss of enerav Nausea/abd distress Re•x eriencln 1...Stress Affective Anxiety Dissociative 3 or more 0 De resslve E lsode 5 or more in 2 wks 0 Panic Attack 4+ s toms within 10 minutes Numbing

  11. Reuse of organobentonites with a carbon dioxide responsive solvent.

    PubMed

    Luan, Ling-Yu; Zhang, Li; Wang, Li-Hong

    2018-05-22

    Synthesized organobentonite (SOB), montmorillonite (MMT), and commercial organobentonite (COB) were used as adsorbents for paraffin oil, a model pollutant in land-based oil spills and oil pipeline rupture. The characterization of clays was carried out with scanning electron microscopy (SEM), thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). After adsorption, oil was separated from adsorbents with a carbon dioxide responsive solvent N,N-dimethylcyclohexylamine (DMCHA), and DMCHA was subsequently separated from paraffin oil upon CO 2 bubbling instead of distillation with high energy cost. The adsorption capacity of oil to SOB, MMT, and COB was 0.686, 1.124, and 1.239 g/g, respectively. It was found that the adsorption capacity and rinsed amount of the adsorbents depended on the d-spacing, which is related to surfactant content. Electrical conductivity and pH measurements suggested that the separation process occurred via two steps. Firstly, during the initial 35 min, carbonate ions coexisted with bicarbonate ions. Then, only bicarbonate ions existed after the introduction of CO 2 gas for 120 min. Thus, organobentonites were feasible for hydrocarbon adsorption and could be simply reused by an amine-based responsive solvent. This work provided a cost-effective and sustainable method of recycling of organobentonites and the responsive solvent, which can be used to deal with leaked oil and oil spills.

  12. Control of information in working memory: Encoding and removal of distractors in the complex-span paradigm.

    PubMed

    Oberauer, Klaus; Lewandowsky, Stephan

    2016-11-01

    The article reports four experiments with complex-span tasks in which encoding of memory items alternates with processing of distractors. The experiments test two assumptions of a computational model of complex span, SOB-CS: (1) distractor processing impairs memory because distractors are encoded into working memory, thereby interfering with memoranda; and (2) free time following distractors is used to remove them from working memory by unbinding their representations from list context. Experiment 1 shows that distractors are erroneously chosen for recall more often than not-presented stimuli, demonstrating that distractors are encoded into memory. Distractor intrusions declined with longer free time, as predicted by distractor removal. Experiment 2 shows these effects even when distractors precede the memory list, ruling out an account based on selective rehearsal of memoranda during free time. Experiments 3 and 4 test the notion that distractors decay over time. Both experiments show that, contrary to the notion of distractor decay, the chance of a distractor intruding at test does not decline with increasing time since encoding of that distractor. Experiment 4 provides additional evidence against the prediction from distractor decay that distractor intrusions decline over an unfilled retention interval. Taken together, the results support SOB-CS and rule out alternative explanations. Data and simulation code are available on Open Science Framework: osf.io/3ewh7. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Amplification of local changes along the timescale processing hierarchy.

    PubMed

    Yeshurun, Yaara; Nguyen, Mai; Hasson, Uri

    2017-08-29

    Small changes in word choice can lead to dramatically different interpretations of narratives. How does the brain accumulate and integrate such local changes to construct unique neural representations for different stories? In this study, we created two distinct narratives by changing only a few words in each sentence (e.g., "he" to "she" or "sobbing" to "laughing") while preserving the grammatical structure across stories. We then measured changes in neural responses between the two stories. We found that differences in neural responses between the two stories gradually increased along the hierarchy of processing timescales. For areas with short integration windows, such as early auditory cortex, the differences in neural responses between the two stories were relatively small. In contrast, in areas with the longest integration windows at the top of the hierarchy, such as the precuneus, temporal parietal junction, and medial frontal cortices, there were large differences in neural responses between stories. Furthermore, this gradual increase in neural differences between the stories was highly correlated with an area's ability to integrate information over time. Amplification of neural differences did not occur when changes in words did not alter the interpretation of the story (e.g., sobbing to "crying"). Our results demonstrate how subtle differences in words are gradually accumulated and amplified along the cortical hierarchy as the brain constructs a narrative over time.

  14. [Deforestation in the state of Mato Grosso in the book Journey around Brazil 1875-1878, by the doctor João Severiano da Fonseca].

    PubMed

    Ferraro, Mário Roberto; Figueirôa, Silvia Fernanda de Mendonça

    2017-01-01

    This presents reflections on scientific production issued by the Commission for the Demarcation of the Empire's Border Limits with Bolivia, with a focus on the environmental destruction of Mato Grosso state, as reported in João Severiano da Fonseca's book, Journey around Brazil 1875-1878. Fonseca reported severe deforestation on the banks of the river Paraguay and advocated for protectionist measures from the state government. He set out a vision for Mato Grosso's development that involved better use of the state's natural resources, raw materials exports, and regional industrialization support. The methodology created an interface between environmental history and history of the sciences.

  15. Synthesis and Verification of Biobased Terephthalic Acid from Furfural

    NASA Astrophysics Data System (ADS)

    Tachibana, Yuya; Kimura, Saori; Kasuya, Ken-Ichi

    2015-02-01

    Exploiting biomass as an alternative to petrochemicals for the production of commodity plastics is vitally important if we are to become a more sustainable society. Here, we report a synthetic route for the production of terephthalic acid (TPA), the monomer of the widely used thermoplastic polymer poly(ethylene terephthalate) (PET), from the biomass-derived starting material furfural. Biobased furfural was oxidised and dehydrated to give maleic anhydride, which was further reacted with biobased furan to give its Diels-Alder (DA) adduct. The dehydration of the DA adduct gave phthalic anhydride, which was converted via phthalic acid and dipotassium phthalate to TPA. The biobased carbon content of the TPA was measured by accelerator mass spectroscopy and the TPA was found to be made of 100% biobased carbon.

  16. Faradaurate nanomolecules: a superstable plasmonic 76.3 kDa cluster.

    PubMed

    Dass, Amala

    2011-12-07

    Information on the emergence of the characteristic plasmonic optical properties of nanoscale noble-metal particles has been limited, due in part to the problem of preparing homogeneous material for ensemble measurements. Here, we report the identification, isolation, and mass spectrometric and optical characterization of a 76.3 kDa thiolate-protected gold nanoparticle. This giant molecule is far larger than any metal-cluster compound, those with direct metal-to-metal bonding, previously known as homogeneous molecular substances, and is the first to exhibit clear plasmonic properties. The observed plasmon emergence phenomena in nanomolecules are of great interest, and the availability of absolutely homogeneous and characterized samples is thus critical to establishing their origin. © 2011 American Chemical Society

  17. [History of genetics in Brazil: a view from the Museu da Genética at the Universidade Federal do Rio Grande do Sul].

    PubMed

    Souza, Vanderlei Sebastiao de; Dornelles, Rodrigo Ciconet; Coimbra Junior, Carlos E A; Santos, Ricardo Ventura

    2013-06-01

    This work addresses the context of the creation, as well as the structure and contents, of the Museum of Genetics (Museu da Genética), created in 2011 and located in the Department of Genetics of the Federal University of Rio Grande do Sul (Universidade Federal do Rio Grande do Sul), in Porto Alegre, Brazil. The materials available at the Museum of Genetics are a rich resource for research on the history of genetics in Brazil (and especially the genetics of human populations) beginning with the second half of the twentieth century. Despite the prominence of the field of genetics in Brazil, little research has been done on this topic.

  18. Peak Stress Intensity Factor Governs Crack Propagation Velocity In Crosslinked UHMWPE

    PubMed Central

    Sirimamilla, P. Abhiram; Furmanski, Jevan; Rimnac, Clare

    2013-01-01

    Ultra high molecular weight polyethylene (UHMWPE) has been successfully used as a bearing material in total joint replacement components. However, these bearing materials can fail as a result of in vivo static and cyclic loads. Crack propagation behavior in this material has been considered using the Paris relationship which relates fatigue crack growth rate, da/dN (mm/cycle) versus the stress intensity factor range, ΔK (Kmax-Kmin, MPa√m). However, recent work suggests that the crack propagation velocity of conventional UHMWPE is driven by the peak stress intensity (Kmax), not ΔK. The hypothesis of this study is that the crack propagation velocity of highly crosslinked and remelted UHMWPE is also driven by the peak stress intensity, Kmax, during cyclic loading, rather than by ΔK. To test this hypothesis, two highly crosslinked (65 kGy and 100 kGy) and remelted UHMWPE materials were examined. Frequency, waveform and R-ratio were varied between test conditions to determine the governing factor for fatigue crack propagation. It was found that the crack propagation velocity in crosslinked UHMWPE is also driven by Kmax and not ΔK, and is dependent on loading waveform and frequency in a predictable quasi-static manner. The current study supports that crack growth in crosslinked UHMWPE materials, even under cyclic loading conditions, can be described by a relationship between the velocity of crack growth, da/dt and the peak stress intensity, Kmax. The findings suggest that stable crack propagation can occur as a result of static loading only and this should be taken into consideration in design of UHMWPE total joint replacement components. PMID:23165898

  19. Proteolytic processing and activation of Clostridium perfringens epsilon toxin by caprine small intestinal contents.

    PubMed

    Freedman, John C; Li, Jihong; Uzal, Francisco A; McClane, Bruce A

    2014-10-21

    Epsilon toxin (ETX), a pore-forming toxin produced by type B and D strains of Clostridium perfringens, mediates severe enterotoxemia in livestock and possibly plays a role in human disease. During enterotoxemia, the nearly inactive ETX prototoxin is produced in the intestines but then must be activated by proteolytic processing. The current study sought to examine ETX prototoxin processing and activation ex vivo using the intestinal contents of a goat, a natural host species for ETX-mediated disease. First, this study showed that the prototoxin has a KEIS N-terminal sequence with a molecular mass of 33,054 Da. When the activation of ETX prototoxin ex vivo by goat small intestinal contents was assessed by SDS-PAGE, the prototoxin was processed in a stepwise fashion into an ~27-kDa band or higher-molecular-mass material that could be toxin oligomers. Purified ETX corresponding to the ~27-kDa band was cytotoxic. When it was biochemically characterized by mass spectrometry, the copresence of three ETX species, each with different C-terminal residues, was identified in the purified ~27-kDa ETX preparation. Cytotoxicity of each of the three ETX species was then demonstrated using recombinant DNA approaches. Serine protease inhibitors blocked the initial proteotoxin processing, while carboxypeptidase inhibitors blocked further processing events. Taken together, this study provides important new insights indicating that, in the intestinal lumen, serine protease (including trypsin and possibly chymotrypsin) initiates the processing of the prototoxin but other proteases, including carboxypeptidases, then process the prototoxin into multiple active and stable species. Importance: Processing and activation by intestinal proteases is a prerequisite for ETX-induced toxicity. Previous studies had characterized the activation of ETX using only arbitrarily chosen amounts of purified trypsin and/or chymotrypsin. Therefore, the current study examined ETX activation ex vivo by natural host intestinal contents. These analyses demonstrated that (i) ETX processing in host intestinal contents occurs in an ordered, stepwise fashion, (ii) processing of prototoxin by host intestinal contents results in higher-molecular-mass material and 3 distinct ~27-kDa ETX species, and (iii) serine proteases, such as trypsin, chymotrypsin, and other proteases, including carboxypeptidases, play a role in the activation of ETX by intestinal contents. These studies provide new insights into the activation and processing of ETX and demonstrate that this process is more complicated than previously appreciated. Copyright © 2014 Freedman et al.

  20. Rapid classification of pharmaceutical ingredients with Raman spectroscopy using compressive detection strategy with PLS-DA multivariate filters.

    PubMed

    Cebeci Maltaş, Derya; Kwok, Kaho; Wang, Ping; Taylor, Lynne S; Ben-Amotz, Dor

    2013-06-01

    Identifying pharmaceutical ingredients is a routine procedure required during industrial manufacturing. Here we show that a recently developed Raman compressive detection strategy can be employed to classify various widely used pharmaceutical materials using a hybrid supervised/unsupervised strategy in which only two ingredients are used for training and yet six other ingredients can also be distinguished. More specifically, our liquid crystal spatial light modulator (LC-SLM) based compressive detection instrument is trained using only the active ingredient, tadalafil, and the excipient, lactose, but is tested using these and various other excipients; microcrystalline cellulose, magnesium stearate, titanium (IV) oxide, talc, sodium lauryl sulfate and hydroxypropyl cellulose. Partial least squares discriminant analysis (PLS-DA) is used to generate the compressive detection filters necessary for fast chemical classification. Although the filters used in this study are trained on only lactose and tadalafil, we show that all the pharmaceutical ingredients mentioned above can be differentiated and classified using PLS-DA compressive detection filters with an accumulation time of 10ms per filter. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. [Repercussions of the Maria da Penha law in tackling gender violence].

    PubMed

    Meneghel, Stela Nazareth; Mueller, Betânia; Collaziol, Marceli Emer; de Quadros, Maíra Meneghel

    2013-03-01

    This paper presents the declarations about the Maria da Penha law made by a sample of women victims and care workers who handle situations of gender violence in the city of Porto Alegre. The data are part of a study that investigated the critical path followed by women who decide to denounce violence. The statements were selected from 45 semi-structured interviews answered by 21 women and 25 professionals from the police, legal, social and health services and nongovernmental institutions. Data were analyzed using NVivo software and one of the categories selected was the Maria da Penha law. Most respondents mentioned the positive and innovatory aspects of the law, though they also pointed out its limitations. The care workers see the legal device as an important tool for tackling violence, aligned with international conventions, bringing innovations and broadening women's access to justice. In terms of weaknesses, both women and care workers stress the inefficiency in the implementation of protective measures, the lack of material resources and manpower, the fragmentation of the health care network and the movement of conservative sectors in society to delegitimize the law.

  2. Translations on Vietnam. Number 1892. Material on the Fourth Vietnam Workers Party Congress (Selected Speeches)

    DTIC Science & Technology

    1977-02-24

    the 17 political struggle against the enemy’s conscription of troops, fight the enemy in their strongholds in Saigon, Hue and Da Nang and...and feudaL cultures. The state-operated cultural and art units and the cinematography sector must be the main force units in the establishment and

  3. The effects of cross-linked thermo-responsive PNIPAAm-based hydrogel injection on retinal function.

    PubMed

    Turturro, Sanja B; Guthrie, Micah J; Appel, Alyssa A; Drapala, Pawel W; Brey, Eric M; Pérez-Luna, Victor H; Mieler, William F; Kang-Mieler, Jennifer J

    2011-05-01

    There is significant interest in biomaterials that provide sustained release of therapeutic molecules to the retina. Poly(N-isopropylacrylamide) (PNIPAAm)-based materials have received significant attention as injectable drug delivery platforms due to PNIPAAm's thermo-responsive properties at approximately 32 °C. While the drug delivery properties of PNIPAAm materials have been studied extensively, there is a need to evaluate the safety effects of hydrogel injection on retinal function. The purpose of this study was to examine the effect of poly(ethylene glycol) diacrylate (PEG-DA) crosslinked PNIPAAm hydrogel injection on retinal function. Utilizing scanning laser ophthalmoscopy (SLO), optical coherent tomography (OCT), and electroretinography (ERG), retinal function was assessed following hydrogel injection. In region near the hydrogel, there was a significant decrease in arterial and venous diameters (∼4%) and an increase in venous blood velocity (∼8%) 1 week post-injection. Retinal thickness decreased (∼6%) at 1 week and the maximum a- and b-wave amplitudes of ERG decreased (∼15%). All data returned to baseline values after week 1. These data suggest that the injection of PEG-DA crosslinked PNIPAAm hydrogel results in a small transient effect on retinal function without any long-term effects. These results further support the potential of PNIPAAm-based materials as an ocular drug delivery platform. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Physicochemical characteristics and biological activities of polysaccharide fractions from Phellinus baumii cultured with different methods.

    PubMed

    Li, Tingting; Yang, Yan; Liu, Yanfang; Zhou, Shuai; Yan, Meng Qiu; Wu, Di; Zhang, Jingsong; Tang, Chuanhong

    2015-11-01

    Nine polysaccharide fractions were obtained from the fruiting bodies, submerged mycelia, and solid state fermented products of Phellinus baumii using different concentrations of ethanol precipitation. The chemical characteristics and in vitro immunological activities of the nine polysaccharide fractions were compared and studied. Results indicated that the fractions precipitated with 50% ethanol had higher yields of polysaccharides and submerged mycelia contributed to high extraction yields of polysaccharides and possessed higher polysaccharide contents. HPSEC-MALLS-RI analysis showed that the molecular weight (Mw) of polysaccharide fractions from these three materials decreased with the increasing of precipitated ethanol concentration. The Mw of fruiting body polysaccharide fractions ranged from 1.98×10(4)Da to 1.89×10(6)Da. Large-molecular-weight polysaccharides (from 2.11×10(6)Da to 2.01×10(7)Da) were found in submerged mycelia. Some lower-molecular-weight polysaccharide components were found in solid fermented products. Different culture methods contributed to significant differences in monosaccharide components and molar ratios. The 50% ethanol precipitated fractions exhibited more complexity on monosaccharide compositions comparing with fractions precipitated with 30% and 70% ethanol. Polysaccharide fractions derived from submerged mycelia exhibited higher macrophages stimulation activities. Submerged culture was found to be a suitable method to prepare active polysaccharides because of its short culture span and reasonable cost. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Microwave-assisted intramolecular dehydrogenative Diels-Alder reactions for the synthesis of functionalized naphthalenes/solvatochromic dyes.

    PubMed

    Kocsis, Laura S; Benedetti, Erica; Brummond, Kay M

    2013-04-01

    Functionalized naphthalenes have applications in a variety of research fields ranging from the synthesis of natural or biologically active molecules to the preparation of new organic dyes. Although numerous strategies have been reported to access naphthalene scaffolds, many procedures still present limitations in terms of incorporating functionality, which in turn narrows the range of available substrates. The development of versatile methods for direct access to substituted naphthalenes is therefore highly desirable. The Diels-Alder (DA) cycloaddition reaction is a powerful and attractive method for the formation of saturated and unsaturated ring systems from readily available starting materials. A new microwave-assisted intramolecular dehydrogenative DA reaction of styrenyl derivatives described herein generates a variety of functionalized cyclopenta[b]naphthalenes that could not be prepared using existing synthetic methods. When compared to conventional heating, microwave irradiation accelerates reaction rates, enhances yields, and limits the formation of undesired byproducts. The utility of this protocol is further demonstrated by the conversion of a DA cycloadduct into a novel solvatochromic fluorescent dye via a Buchwald-Hartwig palladium-catalyzed cross-coupling reaction. Fluorescence spectroscopy, as an informative and sensitive analytical technique, plays a key role in research fields including environmental science, medicine, pharmacology, and cellular biology. Access to a variety of new organic fluorophores provided by the microwave-assisted dehydrogenative DA reaction allows for further advancement in these fields.

  6. Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes

    PubMed Central

    Kocsis, Laura S.; Benedetti, Erica; Brummond, Kay M.

    2013-01-01

    Functionalized naphthalenes have applications in a variety of research fields ranging from the synthesis of natural or biologically active molecules to the preparation of new organic dyes. Although numerous strategies have been reported to access naphthalene scaffolds, many procedures still present limitations in terms of incorporating functionality, which in turn narrows the range of available substrates. The development of versatile methods for direct access to substituted naphthalenes is therefore highly desirable. The Diels-Alder (DA) cycloaddition reaction is a powerful and attractive method for the formation of saturated and unsaturated ring systems from readily available starting materials. A new microwave-assisted intramolecular dehydrogenative DA reaction of styrenyl derivatives described herein generates a variety of functionalized cyclopenta[b]naphthalenes that could not be prepared using existing synthetic methods. When compared to conventional heating, microwave irradiation accelerates reaction rates, enhances yields, and limits the formation of undesired byproducts. The utility of this protocol is further demonstrated by the conversion of a DA cycloadduct into a novel solvatochromic fluorescent dye via a Buchwald-Hartwig palladium-catalyzed cross-coupling reaction. Fluorescence spectroscopy, as an informative and sensitive analytical technique, plays a key role in research fields including environmental science, medicine, pharmacology, and cellular biology. Access to a variety of new organic fluorophores provided by the microwave-assisted dehydrogenative DA reaction allows for further advancement in these fields. PMID:23609566

  7. Studies on magnetocaloric and magnetic coupling effects =

    NASA Astrophysics Data System (ADS)

    Amaral, Joao Cunha de Sequeira

    O presente trabalho apresenta novas metodologias desenvolvidas para a analise das propriedades magneticas e magnetocaloricas de materiais, sustentadas em consideracoes teoricas a partir de modelos, nomeadamente a teoria de transicoes de fase de Landau, o modelo de campo medio molecular e a teoria de fenomeno critico. Sao propostos novos metodos de escala, permitindo a interpretacao de dados de magnetizacao de materiais numa perspectiva de campo medio molecular ou teoria de fenomeno critico. E apresentado um metodo de estimar a magnetizacao espontanea de um material ferromagnetico a partir de relacoes entropia/magnetizacao estabelecidas pelo modelo de campo medio molecular. A termodinamica das transicoes de fase magneticas de primeira ordem e estudada usando a teoria de Landau e de campo medio molecular (modelo de Bean-Rodbell), avaliando os efeitos de fenomenos fora de equilibrio e de condicoes de mistura de fase em estimativas do efeito magnetocalorico a partir de medidas magneticas. Efeitos de desordem, interpretados como uma distribuicao na interaccao magnetica entre ioes, estabelecem os efeitos de distribuicoes quimicas/estruturais nas propriedades magneticas e magnetocaloricas de materiais com transicoes de fase de segunda e de primeira ordem. O uso das metodologias apresentadas na interpretacao das propriedades magneticas de variados materiais ferromagneticos permitiu obter: 1) uma analise quantitativa da variacao de spin por iao Gadolinio devido a transicao estrutural do composto Gd5Si2Ge2, 2) a descricao da configuracao de cluster magnetico de ioes Mn na fase ferromagnetica em manganites da familia La-Sr e La-Ca, 3) a determinacao dos expoentes criticos β e δ do Niquel por metodos de escala, 4) a descricao do efeito da pressao nas propriedades magneticas e magnetocaloricas do composto LaFe11.5Si1.5 atraves do modelo de Bean-Rodbell, 5) uma estimativa da desordem em manganites ferromagneticas com transicoes de segunda e primeira ordem, 6) uma descricao de campo medio das propriedades magneticas da liga Fe23Cu77, 7) o estudo de efeitos de separacao de fase na familia de compostos La0.70-xErxSr0.30MnO3 e 8) a determinacao realista da variacao de entropia magnetica na familia de compostos de efeito magnetocalorico colossal Mn1-x-yFexCryAs.

  8. [Regulation of moxibustion for expression of gastric mucosa cell-related marker protein in rats with acute gastric ulcer].

    PubMed

    Yang, Zong-Bao; Wang, Chen-Guang; Gong, An; Xie, Yu-feng; Liu, Qiong; Yang, Qing

    2013-11-01

    To explore relevant material basis of moxibustion for recovering gastric mucosal lesion. METHODL Forty-five SD rats were randomly divided into a normal goup, a model group, an acupoint group and a control group, 15 rats in the model group and 10 rats in the rest three groups. Except the normal group, binding and cold stress method were used to establish gastric mucosa injury model. The suspended moxibustion was applied in the acupoint group and control group at acupoints of the stomach meridian ("Liangmen" (ST 21) and "Zusanli" (ST36) and control acupoints (Laterally 1cm next to the "Liangmen" (ST 21) and Zusanli" (ST36), once a day, consectutively for 12 days. After 12 days, morphology of gastric mucosal was observed under optical microscope; protein fingerprints of gastric mucosa cell in rats were detected by protein fingerprint technology, weak cation chip and weak anion chip. Also mass to charge ratio of differential proteins in groups were compared and analyzed. Compared with the model group, index of gastric mucosal lesion in the acupoint group was reduced and its morphology was obviously improved (P<0.05). Campared with control group, index and morphology of gastric mucosal lesion were significantly improved in the acupoint group (P<0.05). According to test of weak cation chip, there was four marker proteins that had expression differences, indicating moxibustion at acupoints of stomach meridian could inrease expression of three marker protein whose molecular weight was 1354Da, 5692Da and 8432Da (all P<0.05) while reduce expression of marker protein with molecular weight of 3287Da (_<0.05). According to test of weak anion chip, moxibustion at acupoints of stomach meridian could increase expression of three marker proteins whose molecular weight was 2412 Da, 3026Da and 6475 Da (allP<0.05). Moxibustion at acupoints of the stomach meridian could regulate differential expression of gastric mucosa cell-related marker protein in rats with acute gastric ulcer and recover gastric mucosal lesion, it's effect is better than that of the points of laterally 1 cm next to acupoint.

  9. Microstructure design of titanate-based electroceramics =

    NASA Astrophysics Data System (ADS)

    Amaral, Luis Miguel de Almeida

    Electrocerâmicos sao uma classe de materiais avancados com propriedades electricas valiosas para aplicacoes. Estas propriedades sao geralmente muito dependentes da microestrutura dos materiais. Portanto, o objectivo geral deste trabalho e investigar o desenho da resposta dielectrica de filmes espessos obtidos por Deposicao Electroforetica (EPD) e cerâmicos monoliticos, atraves do controlo da evolucao da microestrutura durante a sinterizacao de electrocerâmicos a base de titanatos. Aplicacoes sem fios na industria microelectronica e de comunicacoes, em rapido crescimento, tornaram-se um importante mercado para os fabricantes de semicondutores. Devido a constante necessidade de miniaturizacao, reducao de custos e maior funcionalidade e integracao, a tecnologia de filmes espessos esta a tornar-se uma abordagem de processamento de materiais funcionais cada vez mais importante. Uma tecnica adequada neste contexto e EPD. Os filmes espessos resultantes necessitam de um passo subsequente de sinterizacao que e afectada pelo substrato subjacente, tendo este um forte efeito sobre a evolucao da microestrutura. Relacionado com a miniaturizacao e a discriminacao do sinal, materiais dielectricos usados como componentes operando a frequencias das microondas em aplicacoes na industria microelectronica de comunicacoes devem apresentar baixas perdas dielectricas e elevadas permitividade dielectrica e estabilidade com a temperatura. Materiais do sistema BaO-Ln2O3- TiO2 (BLnT: Ln = La ou Nd), como BaLa4Ti4O15 (BLT) e Ba4.5Nd9Ti18O54 (BNT), cumprem esses requisitos e sao interessantes para aplicacoes, por exemplo, em estacoes de base para comunicacoes moveis ou em ressonadores para telefones moveis, onde a miniaturizacao dos dispositivos e muito importante. Por sua vez, o titanato de estroncio (SrTiO3, STO) e um ferroelectrico incipiente com constante dielectrica elevada e baixas perdas, que encontra aplicacao em, por exemplo, condensadores de camada interna, tirando partido de fronteiras de grao altamente resistivas. A dependencia da permitividade dielectrica do campo electrico aplicado torna este material muito interessante para aplicacoes em dispositivos de microondas sintonizaveis. Materiais a base de STO sao tambem interessantes para aplicacoes termoelectricas, que podem contribuir para a reducao da actual dependencia de combustiveis fosseis por meio da geracao de energia a partir de calor desaproveitado. No entanto, as mesmas fronteiras de grao resistivas sao um obstaculo relativamente a eficiencia do STO para aplicacoes termoelectricas. (Abstract shortened by ProQuest.).

  10. International Nosocomial Infection Control Consortium Findings of Device-Associated Infections Rate in an Intensive Care Unit of a Lebanese University Hospital

    PubMed Central

    Kanj, SS; Kanafani, ZA; Sidani, N; Alamuddin, L; Zahreddine, N; Rosenthal, VD

    2012-01-01

    Objectives: To determine the rates of device-associated healthcare-associated infections (DA-HAI), microbiological profile, bacterial resistance, length of stay (LOS), excess mortality and hand hygiene compliance in one intensive care unit (ICU) of a hospital member of the International Infection Control Consortium (INICC) in Beirut, Lebanon. Materials and Methods: An open label, prospective cohort, active DA-HAI surveillance study was conducted on adults admitted to a tertiary-care ICU in Lebanon from November 2007 to March 2010. The protocol and methodology implemented were developed by INICC. Data collection was performed in the participating ICUs. Data uploading and analyses were conducted at INICC headquarters on proprietary software. DA-HAI rates were recorded by applying the definitions of the National Healthcare Safety Network (NHSN) at the US Centers for Disease Control and Prevention (CDC). We analyzed the DA-HAI, mechanical ventilator-associated pneumonia (VAP), central line-associated bloodstream infection (CLA-BSI), and catheter-associated urinary tract infection (CAUTI) rates, microorganism profile, excess LOS, excess mortality, and hand hygiene compliance. Results: A total of 666 patients hospitalized for 5,506 days acquired 65 DA-HAIs, an overall rate of 9.8% [(95% confidence interval (CI) 7.6–12.3], and 11.8 (95% CI 9.1–15.0) DA-HAIs per 1000 ICU-days. The CLA-BSI rate was 5.2 (95% CI 2.8–8.7) per 1000 catheter-days; the VAP rate was 8.1 (95% CI 5.5–11.7) per 1000 ventilator-days; and the CAUTI rate was 4.1 (95% CI 2.6–6.2) per 1000 catheter-days. LOS of patients was 7.3 days for those without DA-HAI, 13.8 days for those with CLA-BSI, 18.8 days for those with VAP. Excess mortality was 40.9% [relative risk (RR) 3.14; P 0.004] for CLA-BSI. Mortality of VAP and CAUTI was not significantly different from patients without DA-HAI. Escherichia coli was the most common isolated microorganism. Overall hand hygiene compliance was 84.9% (95% CI 82.3–87.3). Conclusions: DA-HAI rates, bacterial resistance, LOS and mortality were moderately high, below INICC overall data and above CDC-NHSN data. Infection control programs including surveillance and antibiotic policies are essential and continue to be a priority in Lebanon. PMID:22529622

  11. Doping as a means to probe the potential dependence of dopamine adsorption on carbon-based surfaces: A first-principles study

    NASA Astrophysics Data System (ADS)

    Aarva, Anja; Laurila, Tomi; Caro, Miguel A.

    2017-06-01

    In this work, we study the adsorption characteristics of dopamine (DA), ascorbic acid (AA), and dopaminequinone (DAox) on carbonaceous electrodes. Our goal is to obtain a better understanding of the adsorption behavior of these analytes in order to promote the development of new carbon-based electrode materials for sensitive and selective detection of dopamine in vivo. Here we employ density functional theory-based simulations to reach a level of detail that cannot be achieved experimentally. To get a broader understanding of carbonaceous surfaces with different morphological characteristics, we compare three materials: graphene, diamond, and amorphous carbon (a-C). Effects of solvation on adsorption characteristics are taken into account via a continuum solvent model. Potential changes that take place during electrochemical measurements, such as cyclic voltammetry, can also alter the adsorption behavior. In this study, we have utilized doping as an indirect method to simulate these changes by shifting the work function of the electrode material. We demonstrate that sp2- and sp3-rich materials, as well as a-C, respond markedly different to doping. Also the adsorption behavior of the molecules studied here differs depending on the surface material and the change in the surface potential. In all cases, adsorption is spontaneous, but covalent bonding is not detected in vacuum. The aqueous medium has a large effect on the adsorption behavior of DAox, which reaches its highest adsorption energy on diamond when the potential is shifted to more negative values. In all cases, inclusion of the solvent enhances the charge transfer between the slab and DAox. Largest differences in adsorption energy between DA and AA are obtained on graphene. Gaining better understanding of the behavior of the different forms of carbon when used as electrode materials provides a means to rationalize the observed complex phenomena taking place at the electrodes during electrochemical oxidation/reduction of these biomolecules.

  12. The SUPERCOMET 2 Project: Teacher Seminar and Teacher Guide

    NASA Astrophysics Data System (ADS)

    Engstrom, V.; Ireson, G.; Latal, H.; Mathelitsch, L.; Michelini, M.; Peeters, W.; Rath, G.

    2008-05-01

    The Leonardo da Vinci pilot projects SUPERCOMET (2001-2004) and SUPERCOMET 2 (2004-2007) developed and tested teacher training materials for active, minds-on learning of electromagnetism and superconductivity at the level of upper secondary school. New multimedia materials for the pupils supported the teacher materials, including a teacher seminar in 4 half-day modules detailing the scientific contents, teaching methods, using ICT in physics teaching and learning, online collaboration and further resources for exploring the selected topics. The aim of these projects were to improve the quality of physics teaching on a European level, involving a combined total of 45 partners in 16 countries, and conducting trials at 67 schools with approx. 230 teachers, 280 trainee teachers and 2200 pupils. New follow-up projects develop hands-on materials for carrying out the activities described in the teacher guide and seminars and additional teacher materials involving modelling, simulations and data logging.

  13. Synthesis and Verification of Biobased Terephthalic Acid from Furfural

    PubMed Central

    Tachibana, Yuya; Kimura, Saori; Kasuya, Ken-ichi

    2015-01-01

    Exploiting biomass as an alternative to petrochemicals for the production of commodity plastics is vitally important if we are to become a more sustainable society. Here, we report a synthetic route for the production of terephthalic acid (TPA), the monomer of the widely used thermoplastic polymer poly(ethylene terephthalate) (PET), from the biomass-derived starting material furfural. Biobased furfural was oxidised and dehydrated to give maleic anhydride, which was further reacted with biobased furan to give its Diels-Alder (DA) adduct. The dehydration of the DA adduct gave phthalic anhydride, which was converted via phthalic acid and dipotassium phthalate to TPA. The biobased carbon content of the TPA was measured by accelerator mass spectroscopy and the TPA was found to be made of 100% biobased carbon. PMID:25648201

  14. Microbiological Analysis of Surfaces of Leonardo Da Vinci's Atlantic Codex: Biodeterioration Risk.

    PubMed

    Tarsitani, Gianfranco; Moroni, Catia; Cappitelli, Francesca; Pasquariello, Giovanna; Maggi, Oriana

    2014-01-01

    Following the discovery of discoloration on some pages of the Atlantic Codex (AC) of Leonardo da Vinci kept in the Biblioteca Ambrosiana in Milan, some investigations have been carried out to verify the presence of microorganisms, such as bacteria and fungi. To verify the presence of microorganisms a noninvasive method of sampling has been used that was efficient and allowed us to highlight the microbial facies of the material that was examined using conventional microbiological techniques. The microclimatic conditions in the storage room as well as the water content of the volume were also assessed. The combined observations allowed the conclusion that the discoloration of suspected biological origin on some pages of AC is not related to the presence or current attack of microbial agents.

  15. Microbiological Analysis of Surfaces of Leonardo Da Vinci's Atlantic Codex: Biodeterioration Risk

    PubMed Central

    Moroni, Catia; Pasquariello, Giovanna; Maggi, Oriana

    2014-01-01

    Following the discovery of discoloration on some pages of the Atlantic Codex (AC) of Leonardo da Vinci kept in the Biblioteca Ambrosiana in Milan, some investigations have been carried out to verify the presence of microorganisms, such as bacteria and fungi. To verify the presence of microorganisms a noninvasive method of sampling has been used that was efficient and allowed us to highlight the microbial facies of the material that was examined using conventional microbiological techniques. The microclimatic conditions in the storage room as well as the water content of the volume were also assessed. The combined observations allowed the conclusion that the discoloration of suspected biological origin on some pages of AC is not related to the presence or current attack of microbial agents. PMID:25574171

  16. Association between the concentration of fine particles in the atmosphere and acute respiratory diseases in children.

    PubMed

    Nascimento, Antônio Paula; Santos, Jane Meri; Mill, José Geraldo; Souza, Juliana Bottoni de; Reis, Neyval Costa; Reisen, Valdério Anselmo

    2017-01-12

    To analyze the association between fine particulate matter concentration in the atmosphere and hospital care by acute respiratory diseases in children. Ecological study, carried out in the region of Grande Vitória, Espírito Santo, in the winter (June 21 to September 21, 2013) and summer (December 21, 2013 to March 19, 2014). We assessed data of daily count for outpatient care and hospitalization by respiratory diseases (ICD-10) in children from zero to 12 years in three hospitals in the Region of Grande Vitória. For collecting fine particulate matter, we used portable samplers of particles installed in six locations in the studied region. The Generalized Additive Model with Poisson distribution, fitted for the effects of predictor covariates, was used to evaluate the relationship between respiratory outcomes and concentration of fine particulate matter. The increase of 4.2 µg/m3 (interquartile range) in the concentration of fine particulate matter increased in 3.8% and 5.6% the risk of medical care or hospitalization, respectively, on the same day and with six-day lag from the exposure. We identified positive association between outpatient care and hospitalizations of children under 12 years due to acute respiratory diseases and the concentration of fine particulate matter in the atmosphere. Analisar a associação entre a concentração de material particulado fino na atmosfera e atendimento hospitalar por doenças respiratórias agudas em crianças. Estudo ecológico, realizado na Região da Grande Vitória, ES, no inverno (21 de junho a 21 de setembro de 2013) e no verão (21 de dezembro de 2013 a 19 de março de 2014). Foram avaliados dados de contagem diária de atendimentos ambulatoriais e hospitalizações por doenças respiratórias (CID-10) em crianças de zero a 12 anos em três hospitais da Região da Grande Vitoria. Para a coleta de material particulado fino foram utilizados amostradores portáteis de partículas instalados em seis locais na região estudada. O Modelo Aditivo Generalizado com distribuição de Poisson, ajustado para efeitos das covariáveis preditoras, foi utilizado para avaliar a relação entre os desfechos respiratórios e a concentração de material particulado fino. O incremento de 4,2 µg/m3 (intervalo interquartílico) na concentração de material particulado fino aumentou em 3,8% e 5,6% o risco de atendimento ou internação, respectivamente, no mesmo dia e com seis dias de defasagem da exposição. Foi identificada associação positiva entre atendimentos ambulatoriais e hospitalizações de crianças com até 12 anos devido a doenças respiratórias agudas e a concentração de material particulado fino na atmosfera.

  17. PIXE-electrophoresis shows starving collembolan reallocates protein-bound metals.

    PubMed

    Bengtsson, Göran; Pallon, Jan; Nilsson, Christina; Triebskorn, Rita; Köhler, Heinz-R

    2016-01-01

    One of multiple functions of metalloproteins is to provide detoxification to excess metal levels in organisms. Here we address the induction and persistence of a range of low to high molecular weight copper- and zinc binding proteins in the collembolan species Tetrodontophora bielanensis exposed to copper- and zinc-enriched food, followed by a period of recovery from metal exposure, in absence and presence of food. After 10 days of feeding copper and zinc contaminated yeast, specimens were either moved to ample of leaf litter material from their woodland stand of origin or starved (no food offered). The molecular weight distribution of metal binding proteins was determined by native polyacryl gel electrophoresis. One gel was stained with Comassie brilliant blue and a duplicate gel dried and scanned for the amount of copper and zinc by particle-induced X-ray emission. Specimens exposed to copper and recovered from it with ample of food had copper bound to two groups of rather low molecular weight proteins (40-50 kDa) and two of intermediate size (70-80 kDa). Most zinc in specimens from the woodland stand was bound to two large proteins of about 104 and 106 kDa. The same proteins were holding some zinc in metal-exposed specimens, but most zinc was found in proteins <40 kDa in size. Specimens recovered from metal exposure in presence of ample of food had the same distribution pattern of zinc binding proteins, whereas starved specimens had zinc as well as copper mainly bound to two proteins of 8 and 10 kDa in size. Thus, the induction and distribution of copper- and zinc-binding proteins depend on exposure conditions, and the presence of low molecular weight binding proteins, characteristic of metallothioneins, was mainly limited to starving conditions.

  18. Digital radiographic evaluation of mandibular third molar for age estimation in young adults and adolescents of South Indian population using modified Demirjian's method

    PubMed Central

    Mohammed, Rezwana Begum; Koganti, Ravichandra; Kalyan, Siva V.; Tircouveluri, Saritha; Singh, Johar Rajvinder; Srinivasulu, Enganti

    2014-01-01

    In recent years, it has become increasingly important to determine the age of living people for a variety of reasons, including identifying criminal and legal responsibility and for many other social events such as birth certificate, marriage, beginning a job, joining the army and retirement Objectives: The aim of this study was to assess the developmental stages of mandibular third molar for estimation of dental age (DA) in different age groups and to evaluate the possible correlation between DA and chronological age (CA) in South Indian population. Materials and Methods: Digital orthopantomography of 330 subjects (165 males, 165 females) who fit the study and the criteria were obtained. Assessment of mandibular third molar development was performed using Demirjian et al., modified method and DA was assessed using tooth specific stages. Results and Discussion: The present study showed a significant correlation between DA and CA in both males and females. Third molar development commenced around 9 years and root completion takes place around 18.9 years in males and in females 9 years and 18.6 years respectively. Demirjian modified method underestimated the mean age of males by 0.8 years and females by 0.5 years and also showed that females mature earlier than males in selected population. Conclusion: Digital radiographic assessment of mandibular third molar development can be used to generate mean DA using Demirjian modified method and also the estimated age range for an individual of unknown CA. Since the Demirjian method is based on French-Canadian population, to enhance the accuracy of forensic age estimates based on third molar development, the use of population-specific standards is recommended. PMID:25177143

  19. Hyperspectral Imaging and Support Vector Machine: A Powerful Combination to Differentiate Black Cohosh (Actaea racemosa) from Other Cohosh Species.

    PubMed

    Tankeu, Sidonie; Vermaak, Ilze; Chen, Weiyang; Sandasi, Maxleene; Kamatou, Guy; Viljoen, Alvaro

    2018-04-01

    Actaea racemosa (black cohosh) has a history of traditional use in the treatment of general gynecological problems. However, the plant is known to be vulnerable to adulteration with other cohosh species. This study evaluated the use of shortwave infrared hyperspectral imaging (SWIR-HSI) in tandem with chemometric data analysis as a fast alternative method for the discrimination of four cohosh species ( Actaea racemosa, Actaea podocarpa, Actaea pachypoda, Actaea cimicifuga ) and 36 commercial products labelled as black cohosh. The raw material and commercial products were analyzed using SWIR-HSI and ultra-high-performance liquid chromatography coupled to mass spectrometry (UHPLC-MS) followed by chemometric modeling. From SWIR-HSI data (920 - 2514 nm), the range containing the discriminating information of the four species was identified as 1204 - 1480 nm using Matlab software. After reduction of the data set range, partial least squares discriminant analysis (PLS-DA) and support vector machine discriminant analysis (SVM-DA) models with coefficients of determination ( R2 ) of ≥ 0.8 were created. The novel SVM-DA model showed better predictions and was used to predict the commercial product content. Seven out of 36 commercial products were recognized by the SVM-DA model as being true black cohosh while 29 products indicated adulteration. Analysis of the UHPLC-MS data demonstrated that six commercial products could be authentic black cohosh. This was confirmed using the fragmentation patterns of three black cohosh markers (cimiracemoside C; 12- β ,21-dihydroxycimigenol-3- O -L-arabinoside; and 24- O -acetylhydroshengmanol-3- O - β -D-xylopyranoside). SWIR-HSI in conjunction with chemometric tools (SVM-DA) could identify 80% adulteration of commercial products labelled as black cohosh. Georg Thieme Verlag KG Stuttgart · New York.

  20. Modification of linear prepolymers to tailor heterogeneous network formation through photo-initiated Polymerization-Induced Phase Separation

    PubMed Central

    Szczepanski, Caroline R.; Stansbury, Jeffrey W.

    2015-01-01

    Polymerization-induced phase separation (PIPS) was studied in ambient photopolymerizations of triethylene glycol dimethacrylate (TEGDMA) modified by poly(methyl methacrylate) (PMMA). The molecular weight of PMMA and the rate of network formation (through incident UV-irradiation) were varied to influence both the promotion of phase separation through increases in overall free energy, as well as the extent to which phase development occurs during polymerization through diffusion prior to network gelation. The overall free energy of the polymerizing system increases with PMMA molecular weight, such that PIPS is promoted thermodynamically at low loading levels (5 wt%) of a higher molecular weight PMMA (120 kDa), while a higher loading level (20 wt%) is needed to induce PIPS with lower PMMA molecular weight (11 kDa), and phase separation was not promoted at any loading level tested of the lowest molecular weight PMMA (1 kDa). Due to these differences in overall free energy, systems modified by PMMA (11 kDa) underwent phase separation via Nucleation and Growth, and systems modified by PMMA (120 kDa), followed the Spinodal Decomposition mechanism. Despite differences in phase structure, all materials form a continuous phase rich in TEGDMA homopolymer. At high irradiation intensity (Io=20mW/cm2), the rate of network formation prohibited significant phase separation, even when thermodynamically preferred. A staged curing approach, which utilizes low intensity irradiation (Io=300µW/cm2) for the first ~50% of reaction to allow phase separation via diffusion, followed by a high intensity flood-cure to achieve a high degree of conversion, was employed to form phase-separated networks with reduced polymerization stress yet equivalent final conversion and modulus. PMID:26190865

  1. International Workshop on Gravel-Bed Rivers. Dynamics of Gravel-Bed Rivers (3rd), held in Firenze - Poggio a Caiano Italy on September 24-28, 1990

    DTIC Science & Technology

    1990-07-31

    Geol., 22, 97-120. Wymer, J.J. (1968). Lower Palaeolithic Archaeology in Britain, John Baker, London. Wymer, J.J. (1976), The interpretation of... Palaeolithic cultural and faunal material found in Pleistocene sediments, in, Geo-archaeology, Davidson, D.A. and Shackley, M.L. (eds.), Duckworth, London, pp

  2. A Multi-Scale Modeling Framework for Shear Initiated Reactions in Energetic Materials

    DTIC Science & Technology

    2013-07-01

    Laboratory, 2004. 10. Fermen-Coker, M., “Numerical Simulation of Adiabatic Shear Bands in Ti-6Al-4V Alloy Due to Fragment Impact,” ARL-RP-91; U.S...V.G., “Application of the Morse Potential Function to Cubic Metals” Phys. Rev., Vol. 114, pp. 687- 690 , 1959. 15. McQuarrie, D.A., Statistical

  3. Integrating Adaptability into Special Operations Forces Intermediate Level Education

    DTIC Science & Technology

    2010-10-01

    This model is based on the Experiential Learning Theory (ELT), which states that learning occurs by the transfer of experience into knowledge ( Kolb ...Report 529. Arlington, VA. Kolb , D.A., Boyatzis, R.E., & Mainemelis, C. (2000). Experiential Learning Theory : Previous research and new dimensions. In...adaptive thinking materials. Integrating this information will provide some continuity among concepts for instruction. Experiential Learning Model

  4. Culture, Polymerase Chain Reaction and Restriction Fragment Length Polymorphism Studies in Bartonella bacilliformis

    DTIC Science & Technology

    1998-09-22

    within the BA lesions ofHIV-infected patients that appeared similar to the CSD bacillus. ReIman et aI. provided the first infotmation on the genus of the...1993. 31(7): 1730-1734. 21. ReIman DA. Bacillary angiomatosis and Rochalimaea species. Curro CUn. Top. Infect. Dis. pp. 205-219. MElliODS and MATERIALS

  5. JPRS Report, West Europe, Reference Aid, Acronyms and Abbreviations of Portugal

    DTIC Science & Technology

    1988-09-02

    Internacional, Ltd. AML Auto Metralhadora Ligeira AN Assembleia Nacional ANA Aeroportos e Navegacao Aerea ANASD ^ Associacao Nacional dos...de Informacoes ANIC ^ Associacao Nacional dos Industriais de Conservas ANIMEE Associac’ao Nacional dos Industriais de Material Electrico e...Produtos Electricos SIPIP ^ Servico de Informacao Previa ao Investidor Potencial SIRP ^ Sistema de Informac’oes da Repüblica Portuguesa SIS

  6. Simulation of Delamination Under High Cycle Fatigue in Composite Materials Using Cohesive Models

    NASA Technical Reports Server (NTRS)

    Camanho, Pedro P.; Turon, Albert; Costa, Josep; Davila, Carlos G.

    2006-01-01

    A new thermodynamically consistent damage model is proposed for the simulation of high-cycle fatigue crack growth. The basis for the formulation is an interfacial degradation law that links Fracture Mechanics and Damage Mechanics to relate the evolution of the damage variable, d, with the crack growth rate da/dN. The damage state is a function of the loading conditions (R and (Delta)G) as well as the experimentally-determined crack growth rates for the material. The formulation ensures that the experimental results can be reproduced by the analysis without the need of additional adjustment parameters.

  7. Modeling and optimal design of an optical MEMS tactile sensor for use in robotically assisted surgery

    NASA Astrophysics Data System (ADS)

    Ahmadi, Roozbeh; Kalantari, Masoud; Packirisamy, Muthukumaran; Dargahi, Javad

    2010-06-01

    Currently, Minimally Invasive Surgery (MIS) performs through keyhole incisions using commercially available robotic surgery systems. One of the most famous examples of these robotic surgery systems is the da Vinci surgical system. In the current robotic surgery systems like the da Vinci, surgeons are faced with problems such as lack of tactile feedback during the surgery. Therefore, providing a real-time tactile feedback from interaction between surgical instruments and tissue can help the surgeons to perform MIS more reliably. The present paper proposes an optical tactile sensor to measure the contact force between the bio-tissue and the surgical instrument. A model is proposed for simulating the interaction between a flexible membrane and bio-tissue based on the finite element methods. The tissue is considered as a hyperelastic material with the material properties similar to the heart tissue. The flexible membrane is assumed as a thin layer of silicon which can be microfabricated using the technology of Micro Electro Mechanical Systems (MEMS). The simulation results are used to optimize the geometric design parameters of a proposed MEMS tactile sensor for use in robotic surgical systems to perform MIS.

  8. Analysis and toxicity of 59 PAH in petrogenic and pyrogenic environmental samples including dibenzopyrenes, 7H-benzo[c]fluorene, 5-methylchrysene and 1-methylpyrene.

    PubMed

    Richter-Brockmann, Sigrid; Achten, Christine

    2018-06-01

    In this study 59 PAH were analyzed in samples of petrogenic and pyrogenic sources as well as mixed environmental matrices. Among the analytes, PAH of molecular weights from 128 Da to 302 Da in alkylated and in native form were included. Results show that non-EPA PAH make up 69.3–95.1% of the overall toxic equivalents (TEQ) as based on the toxic equivalent factors (TEF) of 24 PAH. Particularly 7H-benzo[c]fluorene, dibenzopyrene isomers and alkylated PAH (in particular 5-methylchrysene and 1-methylpyrene) turned out to have a huge impact on the toxicity and must not be neglected in future risk assessment. In detail, dibenzopyrenes have a high impact on toxicity predominantly in pyrogenic materials (21% to 84%; mean: 59%) whereas 7H-benzo[c]fluorene dominates toxicity of petrogenic materials (up to 80%; mean: 26%). However, in the studied mixed environmental samples the toxic impact of both groups together is as high as about 80%. Many non-EPA PAH are not considered in risk assessment and amongst them there are some very toxic ones. This needs to be carefully evaluated in future studies.

  9. Sulphur-oxidizing and sulphate-reducing communities in Brazilian mangrove sediments.

    PubMed

    Varon-Lopez, Maryeimy; Dias, Armando Cavalcante Franco; Fasanella, Cristiane Cipolla; Durrer, Ademir; Melo, Itamar Soares; Kuramae, Eiko Eurya; Andreote, Fernando Dini

    2014-03-01

    Mangrove soils are anaerobic environments rich in sulphate and organic matter. Although the sulphur cycle is one of the major actors in this ecosystem, little is known regarding the sulphur bacteria communities in mangrove soils. We investigated the abundance, composition and diversity of sulphur-oxidizing (SOB) and sulphate-reducing (SRB) bacteria in sediments from three Brazilian mangrove communities: two contaminated, one with oil (OilMgv) and one with urban waste and sludge (AntMgv), and one pristine (PrsMgv). The community structures were assessed using quantitative real-time polymerase chain reaction (qPCR), polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and clone libraries, using genes for the enzymes adenosine-5'-phosphosulphate reductase (aprA) and sulphite reductase (Dsr) (dsrB). The abundance for qPCR showed the ratio dsrB/aprA to be variable among mangroves and higher according to the gradient observed for oil contamination in the OilMgv. The PCR-DGGE patterns analysed by Nonmetric Multidimensional Scaling revealed differences among the structures of the three mangrove communities. The clone libraries showed that Betaproteobacteria, Gammaproteobacteria and Deltaproteobacteria were the most abundant groups associated with sulphur cycling in mangrove sediments. We conclude that the microbial SOB and SRB communities in mangrove soils are different in each mangrove forest and that such microbial communities could possibly be used as a proxy for contamination in mangrove forests. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

  10. Collection, processing, and reporting of damage tolerant design data for non-aerospace structural materials

    NASA Technical Reports Server (NTRS)

    Huber, P. D.; Gallagher, J. P.

    1994-01-01

    This report describes the organization, format and content of the NASA Johnson damage tolerant database which was created to store damage tolerant property data for non aerospace structural materials. The database is designed to store fracture toughness data (K(sub IC), K(sub c), J(sub IC) and CTOD(sub IC)), resistance curve data (K(sub R) VS. delta a (sub eff) and JR VS. delta a (sub eff)), as well as subcritical crack growth data (a vs. N and da/dN vs. delta K). The database contains complementary material property data for both stainless and alloy steels, as well as for aluminum, nickel, and titanium alloys which were not incorporated into the Damage Tolerant Design Handbook database.

  11. Microbiological evaluation of the steam sterilization of assembled laparoscopic instruments.

    PubMed

    Camargo, Tamara Carolina de; Graziano, Kazuko Uchikawa; Almeida, Alda Graciele Claudio Dos Santos; Suzuki, Karina; Silva, Cely Barreto da; Pinto, Flávia Morais Gomes

    2016-11-21

    assess the safety of steam sterilization of assembled laparoscopic instruments with challenge contamination. a laboratory experimental study, using as test samples trocars and laparoscopic graspers. Geobacillus stearothermophillus ATCC-7953 was used, with a microbial population of 106UFC/Filter paper substrate, removed from the biological indicator. Three of them were introduced into each instrument at the time of assembly, and sterilized at pressurized saturated steam, 134oC for 5 minutes. After sterilization, the instrument was disassembled and each filter paper substrate was inoculated in soybean casein culture and incubated at 56oC for 21 days. In case of absence of growth, they were subjected to heat shock of 80oC, for 20 minutes and re-incubated for 72 hours. Sample size: 185 graspers and 185 trocars, with 95% power. We paired the experiments with comparative negative control groups (5 graspers and 5 trocars with challenge contamination, sterilized disassembled) and positive control (30 filter paper supports, unsterilized), subject to the same incubation procedures. there was no microbial growth in experimental and negative control. The results of the positive control were satisfactory. this study provided strong scientific evidence to support the safety of steam sterilizing of the assembled laparoscopic instrument. avaliar a segurança da esterilização a vapor, do instrumental laparoscópico montado com desafio da contaminação. estudo experimental laboratorial, cujo corpo de prova foram trocarte e pinça laparoscópica. Utilizou-se esporos Geobacillus stearothermophillus ATCC-7953, com população microbiana de 106UFC/suporte de papel filtro, removidos do indicador biológico. Três deles foram introduzidos no interior de cada instrumento, no momento da montagem, sendo esterilizados a vapor saturado sob pressão, 134oC por 5 minutos. Depois da esterilização, o instrumental foi desmontado, e cada suporte de papel filtro foi inoculado em meio de cultura de caseína soja, incubado a 56oC por 21 dias. Não havendo crescimento, foram submetidos a um choque térmico de 80oC, por 20 minutos e reincubados por 72 horas. Tamanho da amostra, 185 pinças e 185 trocartes, com poder de 95%. Os experimentos foram acompanhados dos grupos controle negativo comparativo (5 pinças e 5 trocartes com contaminação desafio, esterilizados desmontados) e positivo (30 suportes de papel filtro, não esterilizados), submetidos aos mesmos procedimentos de incubação. não houve nenhum crescimento microbiano nos grupos experimental e controle negativo. Os resultados do controle positivo foram satisfatórios. este estudo forneceu fortes evidências científicas para sustentar a segurança da prática de esterilização a vapor do instrumental laparoscópico montado. evaluar la seguridad de la esterilización a través de vapor, de instrumental laparoscópico previamente montado con desafío de contaminación. estudio experimental en laboratorio, cuyo cuerpo de prueba fueron trócarte y pinza laparoscópica. Se utilizó esporas Geobacillus stearothermophilus ATCC-7953, con población microbiana de 106UFC/soporte de papel filtro, removidos del indicador biológico. Tres de ellos fueron introducidos en el interior de cada instrumento, en el momento del montaje, los que fueron esterilizados a vapor saturado bajo presión, 134oC por 5 minutos. Después de la esterilización, el instrumental fue desmontado y cada soporte de papel filtro fue inoculado en medio de una cultura de caseína y soya, incubado a 56oC por 21 días. No habiendo crecimiento, fueron sometidos a un choque térmico de 80oC, por 20 minutos y nuevamente incubados por 72 horas. La muestra estuvo constituida por 185 pinzas y 185 trócartes, con poder de 95%. Los experimentos fueron acompañados en los grupos: control negativo comparativo (5 pinzas y 5 trócartes con contaminación desafío, esterilizados desmontados) y positivo (30 soportes de papel filtro, no esterilizados), sometidos a los mismos procedimientos de incubación. no se encontró crecimiento microbiano en los grupos experimental y control negativo. Los resultados del control positivo fueron satisfactorios. este estudio suministra fuertes evidencias científicas para sustentar que la práctica, de esterilización a vapor del instrumental laparoscópico montado, es segura.

  12. Ensino de Astronomia no Ensino Médio

    NASA Astrophysics Data System (ADS)

    Albrecht, E.; Voelzke, M. R.

    2008-09-01

    O presente trabalho de intervenção foi realizado junto a Escola Estadual Colônia dos Pescadores na cidade de Caraguatatuba, com três turmas do terceiro ano do Ensino Médio, envolvendo 119 alunos, 40 na turma A, 40 na turma B e 39 na turma C. A fase inicial foi composta de um questionário de vinte questões dissertativas e objetivas para diagnosticar nos educandos os conceitos prévios sobre Astronomia e, partindo destes realizar uma interferência nas classes envolvidas utilizando metodologias diferentes sendo elas: a tradicional, onde o professor é um repassador de informações, fazendo uso exclusivo de lousa e giz; a segunda também de forma tradicional, porém com auxílio de multimídia para desenvolvimento das aulas e a terceira sob forma de seminários, elaborados e apresentados pelos educandos, no qual o educador faz apenas as intervenções necessárias. Ao final do trabalho as mesmas turmas da fase inicial orientadas pelo mesmo professor responderam novamente ao questionário proposto para diagnosticar dentre as três metodologias utilizadas qual apresentou melhores resultados, sendo os iniciais comparados com os finais. Quando questionados a respeito do significado de Astronomia observou-se inicialmente que os acertos na turma A foram de 100%,turma B: 64%, turma C: 84%, após a intervenção os acertos foram: 100%, 97% e 85% respectivamente, demonstrando claramente uma absorção de conhecimentos. Quando interrogados sobre quantos planetas você acha que existem em nosso Sistema Solar? os acertos foram: turma A: 39%, turma B: 48% e turma C: 46%, após o desenvolvimento do trabalho os acertos foram 94%, 97% e 90% respectivamente.Dentro das respostas obtidas observa-se que a metodologia tradicional com o auxílio de multimeios, aplicada na turma B, demonstrou melhores resultados, foi a mais significativa.

  13. Improved resolution of 3D printed scaffolds by shrinking.

    PubMed

    Chia, Helena N; Wu, Benjamin M

    2015-10-01

    Three-dimensional printing (3DP) uses inkjet printheads to selectively deposit liquid binder to adjoin powder particles in a layer-by-layer fashion to create a computer-modeled 3D object. Two general approaches for 3DP have been described for biomedical applications (direct and indirect 3DP). The two approaches offer competing advantages, and both are limited by print resolution. This study describes a materials processing strategy to enhance 3DP resolution by controlled shrinking net-shape scaffolds. Briefly, porogen preforms are printed and infused with the desired monomer or polymer solution. After solidification or polymerization, the porogen is leached and the polymer is allowed to shrink by controlled drying. Heat treatment is performed to retain the dimensions against swelling forces. The main objective of this study is to determine the effects of polymer content and post-processing on dimension, microstructure, and thermomechanical properties of the scaffold. For polyethylene glycol diacrylate (PEG-DA), reducing polymer content corresponded with greater shrinkage with maximum shrinkage of ∼80 vol% at 20% vol% PEG-DA. The secondary heat treatment retains the microarchitecture and new dimensions of the scaffolds, even when the heat-treated scaffolds are immersed into water. To demonstrate shrinkage predictability, 3D components with interlocking positive and negative features were printed, processed, and fitted. This material processing strategy provides an alternative method to enhance the resolution of 3D scaffolds, for a wide range of polymers, without optimizing the binder-powder interaction physics to print each material combination. © 2014 Wiley Periodicals, Inc.

  14. Fusing Benzo[c][1,2,5]oxadiazole Unit with Thiophene for Constructing Wide-bandgap High-performance IDT-based Polymer Solar Cell Donor Material.

    PubMed

    Song, Xin; Fan, Meijie; Zhang, Kaili; Ding, Dakang; Chen, Weiye; Li, Yonghai; Yu, Liangmin; Sun, Mingliang; Yang, Renqiang

    2018-04-01

    Benzo[c][1,2,5]oxadiazole (BO) moiety is a strong electron-withdrawing unit compared to benzo[c][1,2,5]thiadiazole (BT). It is usually introduced as an acceptor to construct narrow band-gap donor-acceptor (D-A) materials. Herein, the π-extended conjugated moiety dithieno[3',2':3,4″;2,3″:5,6]benzo[1,2-c][1,2,5]oxadiazole (BOT) was adopted as the acceptor moiety to design D-A polymers. Considering the more extended π-conjugated molecular system of BOT compared to the BO unit, a narrower optical band-gap is expected for BOT-based IDT polymer (PIDT-BOT). Unexpectedly, the UV-vis absorption spectra of PIDT-BOT films display a great hypochromatic shift of about 60 nm compared to a BO-based analog (PIDT-BO). The optical band-gaps of the materials are broadened from 1.63 eV (PIDT-BO) to 2.00 eV (PIDT-BOT) accordingly. Although the range of external quantum efficiency (EQE) of PIDT-BOT-based polymer solar cell (PSC) devices is not as wide as for PIDT-BO-based devices, the EQE response intensities of the PIDT-BOT based device are evidently high. As a result, PSC devices based on PIDT-BOT reveal the best power conversion efficiency at 6.08%. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Effect of wastewater colloids on membrane removal of antibiotic resistance genes.

    PubMed

    Breazeal, Maria V Riquelme; Novak, John T; Vikesland, Peter J; Pruden, Amy

    2013-01-01

    Recent studies have demonstrated that wastewater treatment plants (WWTPs) significantly alter the magnitude and distribution of antibiotic resistance genes (ARGs) in receiving environments, indicating that wastewater treatment represents an important node for limiting ARG dissemination. This study examined the potential for membrane treatment of microconstituent ARGs and the effect of native wastewater colloids on the extent of their removal. Plasmids containing vanA (vancomycin) and bla(TEM) (β-lactam) ARGs were spiked into three representative WWTP effluents versus a control buffer and tracked by quantitative polymerase chain reaction through a cascade of microfiltration and ultrafiltration steps ranging from 0.45 μm to 1 kDa. Significant removal of ARGs was achieved by membranes of 100 kDa and smaller, and presence of wastewater colloids resulted in enhanced removal by 10 kDa and 1 kDa membranes. ARG removal was observed to correlate significantly with the corresponding protein, polysaccharide, and total organic carbon colloidal fractions. Alumina membranes removed ARGs to a greater extent than polyvinylidene fluoride membranes of the same pore size (0.1 μm), but only in the presence of wastewater material. Control studies confirmed that membrane treatment was the primary mechanism of ARG removal, versus other potential sources of loss. This study suggests that advanced membrane treatment technology is promising for managing public health risks of ARGs in wastewater effluents and that removal may even be enhanced by colloids in real-world wastewaters. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Simultaneous determination of L-ascorbic acid, dopamine and uric acid with gold nanoparticles-β-cyclodextrin-graphene-modified electrode by square wave voltammetry.

    PubMed

    Tian, Xianqing; Cheng, Changming; Yuan, Hongyan; Du, Juan; Xiao, Dan; Xie, Shunping; Choi, Martin M F

    2012-05-15

    Graphene decorated with gold nanoparticles (AuNPs-β-CD-Gra) has been synthesized by in situ thermal reduction of graphene oxide and HAuCl(4) with β-cyclodextrin (β-CD) under alkaline condition. The AuNPs-β-CD-Gra product was well characterized by infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and selected area electron diffraction. This material was used to fabricate an AuNPs-β-CD-Gra-modified glassy carbon electrode (GCE) which showed excellent electro-oxidation of l-ascorbic acid (AA), dopamine (DA) and uric acid (UA) in 0.10 M NaH(2)PO(4)-HCl buffer solution (pH 2.0) by square wave voltammetry (SWV). Three well-resolved oxidation peaks of AA and DA and UA were obtained. The AuNPs-β-CD-Gra/GCE exhibits linear responses to AA, DA and UA in the ranges 30-2000, 0.5-150 and 0.5-60 μM, respectively. The detection limits (based on S/N=3 and preconcentration time=3.0 min) for AA, DA and UA are 10, 0.15 and 0.21 μM, respectively. The AuNPs-β-CD-Gra/GCE has been successfully applied to determine UA in human urine with satisfactory results. Our work provides a simple, convenient and green route to synthesize AuNPs on Gra which is potentially useful in electroanalysis. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. A Rapid LC-HRMS Method for the Determination of Domoic Acid in Urine Using a Self-Assembly Pipette Tip Solid-Phase Extraction

    PubMed Central

    Zhang, Yiping; Chen, Dawei; Hong, Zhuan

    2015-01-01

    In this study, we developed a self-assembly pipette tip solid-phase extraction (PTSPE) method using a high molecular weight polymer material (PAX) as the adsorbent for the determination of domoic acid (DA) in human urine samples by liquid chromatography high-resolution mass spectrometry (LC-HRMS) analysis. The PTSPE cartridge, assembled by packing 9.1 mg of PAX as sorbent into a 200 μL pipette tip, showed high adsorption capacity for DA owing to the strong cationic properties of PAX. Compared with conventional SPE, the PTSPE is simple and fast, and shows some advantages in the aspects of less solvent consumption, low cost, the absence of the evaporation step, and short time requirement. All the parameters influencing the extraction efficiency such as pH, the amount of sorbent, the number of aspirating/dispensing cycles, and the type and volume of eluent in PTSPE were carefully investigated and optimized. Under the optimized conditions, the limit of detection (LOD) and limit of quantification (LOQ) values of DA were 0.12 μg/L and 0.37 μg/L respectively. The extraction recoveries of DA from the urine samples spiked at four different concentrations were in a range from 88.4% to 102.5%. The intra- and inter-day precisions varied from 2.1% to 7.6% and from 2.6% to 12.7%, respectively. The accuracy ranged from −1.9% to −7.4%. PMID:26729165

  18. Refining a brief decision aid in stable CAD: cognitive interviews.

    PubMed

    Kelly-Blake, Karen; Clark, Stacie; Dontje, Katherine; Olomu, Adesuwa; Henry, Rebecca C; Rovner, David R; Rothert, Marilyn L; Holmes-Rovner, Margaret

    2014-02-13

    We describe the results of cognitive interviews to refine the "Making Choices©" Decision Aid (DA) for shared decision-making (SDM) about stress testing in patients with stable coronary artery disease (CAD). We conducted a systematic development process to design a DA consistent with International Patient Decision Aid Standards (IPDAS) focused on Alpha testing criteria. Cognitive interviews were conducted with ten stable CAD patients using the "think aloud" interview technique to assess the clarity, usefulness, and design of each page of the DA. Participants identified three main messages: 1) patients have multiple options based on stress tests and they should be discussed with a physician, 2) take care of yourself, 3) the stress test is the gold standard for determining the severity of your heart disease. Revisions corrected the inaccurate assumption of item number three. Cognitive interviews proved critical for engaging patients in the development process and highlighted the necessity of clear message development and use of design principles that make decision materials easy to read and easy to use. Cognitive interviews appear to contribute critical information from the patient perspective to the overall systematic development process for designing decision aids.

  19. Holographic lithography for biomedical applications

    NASA Astrophysics Data System (ADS)

    Stankevicius, E.; Balciunas, E.; Malinauskas, M.; Raciukaitis, G.; Baltriukiene, D.; Bukelskiene, V.

    2012-06-01

    Fabrication of scaffolds for cell growth with appropriate mechanical characteristics is top-most important for successful creation of tissue. Due to ability of fast fabrication of periodic structures with a different period, the holographic lithography technique is a suitable tool for scaffolds fabrication. The scaffolds fabricated by holographic lithography can be used in various biomedical investigations such as the cellular adhesion, proliferation and viability. These investigations allow selection of the suitable material and geometry of scaffolds which can be used in creation of tissue. Scaffolds fabricated from di-acrylated poly(ethylene glycol) (PEG-DA-258) over a large area by holographic lithography technique are presented in this paper. The PEG-DA scaffolds fabricated by holographic lithography showed good cytocompatibility for rabbit myogenic stem cells. It was observed that adult rabbit muscle-derived myogenic stem cells grew onto PEG-DA scaffolds. They were attached to the pillars and formed cell-cell interactions. It demonstrates that the fabricated structures have potential to be an interconnection channel network for cell-to-cell interactions, flow transport of nutrients and metabolic waste as well as vascular capillary ingrowth. These results are encouraging for further development of holographic lithography by improving its efficiency for microstructuring three-dimensional scaffolds out of biodegradable hydrogels

  20. Determination of perfluorinated alkylated substances in sediments and sediment core from the Gulf of Gdańsk, Baltic Sea.

    PubMed

    Falandysz, Jerzy; Rostkowski, Paweł; Jarzyńska, Grażyna; Falandysz, Jaromir J; Taniyasu, Sachi; Yamashita, Nobuyoshi

    2012-01-01

    Perfluorinated alkylated substances (PFAS) have been determined in surface sediments and sediment core from Gulf of Gdańsk, Baltic Sea. Perfluorooctanesulphonate (PFOS), perfluorohexanesulphonate (PFHxS), perfluorodecanoate (PFDA), perfluoronanoate (PFNA), perfluorooctanoate (PFOA), perfluoroheptanoate (PFHpA), perfluoroundecanote (PFUnDA), perfluorododecanoate (PFDoDA) and perfluorohexanoate (PFHxA) were quantified after isotopic dilution ((13)C(4) PFOS and (13)C(4) PFOA), liquid-liquid extractions by methanol and acetonitrile, cleanup by Envi-Carb, OasisWAX and Envi-Carb and final measurement by HPLC-MS/MS. PFOS, PFHxS, PFUnDA, PFDA, PFNA and PFOA were found in Baltic Sea sediments in concentrations exceeding the method limit of quantification (LOQ) of 2 pg/g. PFOS was detected in concentration up to 0.896 ng/g dry weight and PFHxS up to 0.326 ng/g dw, which shows on a weak pollution. PFOS (48-74%) or PFHxS (45-56%) dominated in PFAS composition of sediments surveyed. Supplemental materials are available for this article. Go to the publisher's online edition of the Journal of Environmental Science and Health, Part A to view the free supplemental file.

  1. Three Dimensional Parametric Analyses of Stress Concentration Factor and Its Mitigation in Isotropic and Orthotropic Plate with Central Circular Hole Under Axial In-Plane Loading

    NASA Astrophysics Data System (ADS)

    Nagpal, Shubhrata; Jain, Nitin Kumar; Sanyal, Shubhashis

    2016-01-01

    The problem of finding the stress concentration factor of a loaded rectangular plate has offered considerably analytical difficulty. The present work focused on understanding of behavior of isotropic and orthotropic plate subjected to static in-plane loading using finite element method. The complete plate model configuration has been analyzed using finite element method based software ANSYS. In the present work two parameters: thickness to width of plate (T/A) and diameter of hole to width of plate (D/A) have been varied for analysis of stress concentration factor (SCF) and its mitigation. Plates of five different materials have been considered for complete analysis to find out the sensitivity of stress concentration factor. The D/A ratio varied from 0.1 to 0.7 for analysis of SCF and varied from 0.1 to 0.5 for analyzing the mitigation of SCF. 0.01, 0.05 and 0.1 are considered as T/A ratio for all the cases. The results are presented in graphical form and discussed. The mitigation in SCF reported is very encouraging. The SCF is more sensitive to D/A ratio as compared to T/A.

  2. Biscarbamate Cross-Linked Low-Molecular-Weight Polyethylenimine for Delivering Anti-chordin siRNA into Human Mesenchymal Stem Cells for Improving Bone Regeneration.

    PubMed

    Wang, Chuandong; Yuan, Weien; Xiao, Fei; Gan, Yaokai; Zhao, Xiaotian; Zhai, Zhanjing; Zhao, Xiaoying; Zhao, Chen; Cui, Penglei; Jin, Tuo; Chen, Xiaodong; Zhang, Xiaoling

    2017-01-01

    Small-interfering RNA (siRNA) provides a rapid solution for drug design and provides new methods to develop customizable medicines. Polyethyleneimine 25 kDa (PEI25kDa) is an effective transfection agent used in siRNA delivery. However, the lack of degradable linkage causes undesirable toxicity, hindering its clinical application. We designed a low-molecular-weight cross-linked polyethylenimine named PEI-Et (Mn:1220, Mw:2895) by using degradable ethylene biscarbamate linkage with lower cytotoxicity and higher knockdown efficiency than PEI25kDa in delivery Chordin siRNA to human bone mesenchymal stem cells (hBMSCs). Suppression of Chordin by using anti-Chordin siRNA delivered by PEI-Et improved bone regeneration in vitro and in vivo associated with the bone morphogenetic protein-2 (BMP-2) mediated smad1/5/8 signaling pathway. Results of this study suggest that Chordin siRNA can be potentially used to improve osteogenesis associated with the BMP-2-mediated Smad1/5/8 signaling pathway and biodegradable biscarbamate cross-linked low-molecular-weight polyethylenimine (PEI-Et) is a therapeutically feasible carrier material to deliver anti-Chordin siRNA to hBMSCs.

  3. Material Modeling for Terminal Ballistic Simulation

    DTIC Science & Technology

    1992-09-01

    DYNA-3D-a nonlinear, explicit, three-dimensional finite element code for solid and structural mechanics- user manual. Technical Report UCRL -MA...Rep. UCRL -50108, Rev. 1, Lawrence Livermore Laboratory, 1977. [34] S. P. Marsh. LASL Shock Hugoniot Data. University of California Press, Berkeley, CA...Steinberg. Equation of state and strength properties of selected ma- teriaJs. Tech. Rep. UCRL -MA-106439, Lawrence Livermore National Labo- ratory, 1991. [371

  4. Latex allergens in tire dust and airborne particles.

    PubMed Central

    Miguel, A G; Cass, G R; Weiss, J; Glovsky, M M

    1996-01-01

    The prevalence and severity of latex allergy has increased dramatically in the last 15 years due to exposure to natural rubber products. Although historically this health risk has been elevated in hospital personnel and patients, a recent survey has indicated a significant potential risk for the general population. To obtain a wide-spread source for latex exposure, we have considered tire debris. We have searched for the presence of latex allergens in passenger car and truck tire tread, in debris deposited from the atmosphere near a freeway, and in airborne particulate matter samples representative of the entire year 1993 at two sites in the Los Angeles basin (California). After extraction of the samples with phosphate buffered saline, a modified-ELISA inhibition assay was used to measure relative allergen potency and Western blot analyses were used to identify latex allergens. The inhibition studies with the human IgE latex assay revealed inhibition by the tire tread source samples and ambient freeway dust, as well as by control latex sap and latex glove extracts. Levels of extractable latex allergen per unit of protein extracted were about two orders of magnitude lower for tire tread as compared to latex gloves. Western blot analyses using binding of human IgE from latex-sensitive patients showed a band at 34-36 kDa in all tire and ambient samples. Long Beach and Los Angeles, California, air samples showed four additional bands between 50 and 135 kDa. Alternative Western blot analyses using rabbit IgG raised against latex proteins showed a broad band at 30-50 kDa in all samples, with additional bands in the urban air samples similar to the IgE results. A latex cross-reactive material was identified in mountain cedar. In conclusion, the latex allergens or latex cross-reactive material present in sedimented and airborne particulate material, derived from tire debris, and generated by heavy urban vehicle traffic could be important factors in producing latex allergy and asthma symptoms associated with air pollution particles. Images Figure 1. Figure 2. A Figure 2. B Figure 3. Figure 4. PMID:8959407

  5. Biodegradable packing materials from hydrolysates of collagen waste proteins.

    PubMed

    Langmaier, F; Mokrejs, P; Kolomaznik, K; Mladek, M

    2008-01-01

    Enzymatic hydrolysates of waste collagen proteins (H), from current industrial manufacture (leather, edible meat product casings, etc.) of mean molecular mass 20-30 kDa by a reaction with dialdehyde starch (DAS), produces hydrogels applicable as biodegradable (or even edible) packaging materials for food, cosmetic and pharmaceutical products. Thermo-reversibility of prepared hydrogels is given by concentrations of H and DAS in a reaction mixture. At concentrations of H 25-30% (w/w) and that of DAS 15-20% (related to weight of hydrolysate), thermo-reversible hydrogels arise, which can be processed into packaging materials by a technique similar to that of soft gelatin capsules (SGC). Exceeding the limit of 20% DAS leads to hydrogels that are thermo-reversible only in part, a further increase in DAS concentration then leads to thermo-irreversible gels whose processing into biodegradable packaging materials necessitates employment of other procedures.

  6. Abundâncias de oxigênio e enxofre nas estrelas de tipo solar da vizinhança solar

    NASA Astrophysics Data System (ADS)

    Requeijo, F.; Porto de Mello, G. F.

    2003-08-01

    Alguns resultados sugerem que o Sol seja 58% mais abundante em oxigênio que o meio interestelar local. Esta anomalia parece estender-se para o carbono e o criptônio. Entre as possíveis explicações deste fenômeno estão: uma supernova de tipo II que tenha enriquecido a nebulosa protosolar, tornando-a superabundante em oxigênio; um episódio de infall de material pobre em metais sobre o disco Galático, diluindo o meio interestelar local ou uma migração dinâmica do Sol de uma órbita mais interna da Galáxia para sua posição atual. A escolha entre estes cenários exige o conhecimento preciso da abundância solar em relação às anãs G da vizinhança. Neste contexto, o oxigênio e enxofre, são elementos-chave por serem ambos produzidos pelas supernovas de tipo II, devendo portanto possuir o mesmo padrão de abundância. Este projeto visa esclarecer qual a posição do Sol na distribuição local de abundâncias de enxofre e oxigênio para uma amostra de estrelas de tipo solar com idades e metalicidades bem conhecidas. Para tal, analisamos espectros de alta resolução e alta relação sinal-ruído nas regiões espectrais de ll 6300, 7774 (O) e l8695 (S). Para o enxofre encontramos que o Sol parece ser uma estrela típica dentre as da vizinhança, e que este elemento não mostra a sobreabundância para baixas metalicidades, já bem estabelecida para o oxigênio. Discutimos as abundâncias do enxofre no contexto da Evolução Química da Galáxia. Apresentamos resultados preliminares muito precisos para a linha proibida do oxigênio l6300 e comparamos estes com os obtidos para o tripleto em l7774. Quantificamos os efeitos não-ETL presentes no tripleto em função dos parâmetros atmosféricos estelares.

  7. A comparative study on seismic response of two unstable rock slopes within same tectonic setting but different activity level

    NASA Astrophysics Data System (ADS)

    Kleinbrod, Ulrike; Burjánek, Jan; Hugentobler, Marc; Amann, Florian; Fäh, Donat

    2017-12-01

    In this study, the seismic response of two slope instabilities is investigated with seismic ambient vibration analysis. Two similar sites have been chosen: an active deep-seated slope instability at Cuolm da Vi and the geologically, structurally and morphologically similar, but presently not moving Alp Caschlè slope. Both slopes are located at the upper Vorderrheintal (Canton Graubünden, Switzerland). Ambient vibrations were recorded on both slopes and processed by time-frequency polarization and site-to-reference spectral ratio analysis. The data interpretation shows correlations between degree of disintegration of the rock mass and amplification. However, the ambient vibration analysis conducted, does not allow retrieving a resonance frequency that can be related to the total depth of the instability of Cuolm da Vi. Even though seismic waves can be hardly traced in rock instabilities containing open fractures, it was possible to retrieve a dispersion curve and a velocity profile from the array measurement at Cuolm da Vi due to the high level of disintegration of the rock material down to a depth of about 100 m. From the similar amplification pattern at the two sites, we expect a similar structure, indicating that also the slope at Alp Caschlè was active in the past in a similar manner as Cuolm da Vi. However, a smoother increase of amplification with frequency is observed at Alp Caschlè, which might indicate less disintegration of the rock mass in a particular depth range at this site, when comparing to Cuolm da Vi where a high level of disintegration is observed, resulting from the high activity at the slope. From the frequency-dependent amplification, we can distinguish between two parts within both instabilities, one part showing decreasing disintegration of the rock mass with increasing depth, for the other parts less-fractured blocks are observed. Since the block structures are found in the lower part of the instabilities, they might contribute to the stability of the slopes. Using the velocity profiles, it was possible to estimate the depth of the two largest open fractures (i.e. tension cracks) at Cuolm da Vi.

  8. Electrochemical Capacities of Commercially Available Structural Carbon Fibers, Fabrics, and Papers

    DTIC Science & Technology

    2008-09-01

    Hollingsworth & Vose. A liquid electrolyte of ethylene carbonate: ethyl methyl carbonate (3:7 by weight) with 1.0 M lithium hexafluorophosphate (LiPF6) was...fiber pulp COTS commercial off-the-shelf Da dalton FE-SEM Field Emission Scanning Electron Microscope LiPF6 lithium hexafluorophosphate MWNT...material for anodes in modern technologies, particularly in lithium -ion batteries and electrochemical supercapacitors. Graphitic carbon allows for

  9. The Use of Ion Implantation for Materials Processing.

    DTIC Science & Technology

    1986-03-06

    34 ASME, J. Lub. Technology 105, pp. 534-541 (1983). 89. J. M. Lambert, P. A. Treado, D . Trbojevic , R. G. Allas, A. R. Knudson, G. W. Reynolds, and F. R...Singer and R.G. Vardiman D . In Situ Auger Analysis Of Surface Composition During High Fluence Ion Implantation...Niobium Implantation Of Iron Films ..............................................37 B. D . Sartwell and D.A. Baldwin F. Sputtering And Migration During Ta

  10. 2013 Center for Army Leadership Annual Survey of Army Leadership (CASAL): Main Findings

    DTIC Science & Technology

    2014-04-01

    enhances Esprit de Corps. The Center for Army Profession and Ethic (CAPE) has fielded education and training materials (including doctrine, pamphlets ...videos, brochures , and lesson plans available online) to assist Army leaders in executing this program (The FY14 America’s Army-Our Profession...contribution of warrant officer courses for improving leadership capabilities are not unexpected. However, Department of the Army Pamphlet (DA PAM) 600-3

  11. 2013 CENTER FOR ARMY LEADERSHIP ANNUAL SURVEY OF ARMY LEADERSHIP (CASAL): MAIN FINDINGS

    DTIC Science & Technology

    2014-04-30

    The Center for Army Profession and Ethic (CAPE) has fielded education and training materials (including doctrine, pamphlets , videos, brochures , and...Army Pamphlet (DA PAM) 600-3, Commissioned Officer Development and Career Management, states that a goal of warrant officer training and education... Pamphlet 600-25, U.S. Army noncommissioned officer professional development and career management. Washington, D.C.: Headquarters, Department of the Army

  12. Synaptic Spinules in the Olfactory Circuit of Drosophila melanogaster

    PubMed Central

    Gruber, Lydia; Rybak, Jürgen; Hansson, Bill S.; Cantera, Rafael

    2018-01-01

    Here we report on ultrastructural features of brain synapses in the fly Drosophila melanogaster and outline a perspective for the study of their functional significance. Images taken with the aid of focused ion beam-scanning electron microscopy (EM) at 20 nm intervals across olfactory glomerulus DA2 revealed that some synaptic boutons are penetrated by protrusions emanating from other neurons. Similar structures in the brain of mammals are known as synaptic spinules. A survey with transmission EM (TEM) disclosed that these structures are frequent throughout the antennal lobe. Detailed neuronal tracings revealed that spinules are formed by all three major types of neurons innervating glomerulus DA2 but the olfactory sensory neurons (OSNs) receive significantly more spinules than other olfactory neurons. Double-membrane vesicles (DMVs) that appear to represent material that has pinched-off from spinules are also most abundant in presynaptic boutons of OSNs. Inside the host neuron, a close association was observed between spinules, the endoplasmic reticulum (ER) and mitochondria. We propose that by releasing material into the host neuron, through a process triggered by synaptic activity and analogous to axonal pruning, synaptic spinules could function as a mechanism for synapse tagging, synaptic remodeling and neural plasticity. Future directions of experimental work to investigate this theory are proposed. PMID:29636666

  13. Analysis of the polymeric fractions of scrap from mobile phones using laser-induced breakdown spectroscopy: chemometric applications for better data interpretation.

    PubMed

    Aquino, Francisco W B; Pereira-Filho, Edenir R

    2015-03-01

    Because of their short life span and high production and consumption rates, mobile phones are one of the contributors to WEEE (waste electrical and electronic equipment) growth in many countries. If incorrectly managed, the hazardous materials used in the assembly of these devices can pollute the environment and pose dangers for workers involved in the recycling of these materials. In this study, 144 polymer fragments originating from 50 broken or obsolete mobile phones were analyzed via laser-induced breakdown spectroscopy (LIBS) without previous treatment. The coated polymers were mainly characterized by the presence of Ag, whereas the uncoated polymers were related to the presence of Al, K, Na, Si and Ti. Classification models were proposed using black and white polymers separately in order to identify the manufacturer and origin using KNN (K-nearest neighbor), SIMCA (Soft Independent Modeling of Class Analogy) and PLS-DA (Partial Least Squares for Discriminant Analysis). For the black polymers the percentage of correct predictions was, in average, 58% taking into consideration the models for manufacturer and origin identification. In the case of white polymers, the percentage of correct predictions ranged from 72.8% (PLS-DA) to 100% (KNN). Copyright © 2014 Elsevier B.V. All rights reserved.

  14. The Natural Selection of the Chemical Elements (by R. J. P. Williams and J. J. R. Fraústo da Silva)

    NASA Astrophysics Data System (ADS)

    Kauffman, George B.

    1998-12-01

    Clarendon: New York, 1996. xxvi + 646 pp. Figs., tables. 20.5 x 25.6 cm. ISBN 0-19-855843-0. $80.00. R. J. P. Williams, Royal Society Research Professor Emeritus at Wadham College, Oxford University, and J. J. R. Fraústo da Silva, Professor of Analytical Chemistry at the Instituto Superior Técnico, Universidade Técnica de Lisboa, have collaborated on two previous volumes: New Trends in Bio-inorganic Chemistry (1978) and The Biological Chemistry of the Elements (3rd printing, 1994). Their latest collaborative effort is a book whose ambitious objective is "to show the relationship of every kind of material around us, living and nonliving, to the properties of the chemical elements of the periodic table." The "natural selection" of the chemical elements results from a number of factors, all of which are described in detail. Among these are chemical affinity related to the electronic configuration of their atoms, thermodynamic and kinetic stability, and "functional value to an organisation such as a living system". The physicist's approach to material through phase structure and the phase rule is stressed rather than the chemist's approach through bonding theories. The entire book possesses a strong environmental and interdisciplinary emphasis.

  15. Data communication through multiple physical media: applications to munitions

    NASA Astrophysics Data System (ADS)

    Dhadwal, Harbans S.; Rastegar, Jahangir; Feng, Dake; Kwok, Philip

    2015-05-01

    Electronic systems comprising of subassemblies, distributed across different physical media, require seamless communication between processors and sensors embedded in the disparate volumes. For example, smart munitions systems embed sensors and other key control electronics, throughout the structure, in vastly different physical media. In addition to the obvious space constraints, these structures are subjected to high G forces during launch. Thus, communications through wire harnesses becomes cumbersome, make assembly process and testing difficult, and challenging to make survive high G firing. Here we focus on an approach that takes advantage of the partial optical transparency of epoxy material commonly used in potting electronic components in munitions, as well as the wave guiding that is possible through the body of the munitions wall which is made from composite materials. Experimental results show that a wireless optical link, connecting various parts of the distributed system, is possible at near IR frequencies. Data can be rapidly parsed between a processor, sensors and actuators. We present experimental data for a commercial epoxy system, which is used to embed a number of IrDA devices inside the cone of 120 mm mortar shell. IrDA devices using the FIR data rates establish point-to-point communication through various media, representative of the environment inside the 120 mm mortar cone.

  16. Synaptic Spinules in the Olfactory Circuit of Drosophila melanogaster.

    PubMed

    Gruber, Lydia; Rybak, Jürgen; Hansson, Bill S; Cantera, Rafael

    2018-01-01

    Here we report on ultrastructural features of brain synapses in the fly Drosophila melanogaster and outline a perspective for the study of their functional significance. Images taken with the aid of focused ion beam-scanning electron microscopy (EM) at 20 nm intervals across olfactory glomerulus DA2 revealed that some synaptic boutons are penetrated by protrusions emanating from other neurons. Similar structures in the brain of mammals are known as synaptic spinules. A survey with transmission EM (TEM) disclosed that these structures are frequent throughout the antennal lobe. Detailed neuronal tracings revealed that spinules are formed by all three major types of neurons innervating glomerulus DA2 but the olfactory sensory neurons (OSNs) receive significantly more spinules than other olfactory neurons. Double-membrane vesicles (DMVs) that appear to represent material that has pinched-off from spinules are also most abundant in presynaptic boutons of OSNs. Inside the host neuron, a close association was observed between spinules, the endoplasmic reticulum (ER) and mitochondria. We propose that by releasing material into the host neuron, through a process triggered by synaptic activity and analogous to axonal pruning, synaptic spinules could function as a mechanism for synapse tagging, synaptic remodeling and neural plasticity. Future directions of experimental work to investigate this theory are proposed.

  17. Piezoresponse force microscopy of ferroelectric relaxors =

    NASA Astrophysics Data System (ADS)

    Kiselev, Dmitry

    Nesta tese, ferroelectricos relaxor (I dont know uf the order is correct) de base Pb das familias (Pb,La)(Zr,Ti)O3 (PLZT), Pb(Mg1/3,Nb2/3)O3-PbTiO3 (PMN-PT), Pb(Zn1/3,Nb2/3)O3-PbTiO3 (PZN-PT) foram investigados e analisados. As propriedades ferroelectricas e dielectricas das amostras foram estudadas por metodos convencionais de macro e localmente por microscopia de forca piezoelectrica (PFM). Nos cerâmicos PLZT 9.75/65/35 o contraste da PFM a escala nanometrica foi investigado em funcao do tamanho e orientacao dos graos. Apurou-se que a intensidade do sinal piezoelectrico das nanoestruturas diminui com o aumento da temperatura e desaparece a 490 K (La mol. 8%) e 420 K (9,5%). Os ciclos de histerese locais foram obtidos em funcao da temperatura. A evolucao dos parâmetros macroscopicos e locais com a temperatura de superficie sugere um forte efeito de superficie nas transicoes de fase ferroelectricas do material investigado. A rugosidade da parede de dominio e determinada por PFM para a estrutura de dominio natural existente neste ferroelectrico policristalino. Alem disso, os dominios ferroelectricos artificiais foram criados pela aplicacao de pulsos electricos a ponta do condutor PFM e o tamanho de dominio in-plane foi medido em funcao da duracao do pulso. Todas estas experiencias levaram a conclusao de que a parede de dominio em relaxors do tipo PZT e quase uma interface unidimensional. O mecanismo de contraste na superficie de relaxors do tipo PLZT e medido por PFMAs estruturas de dominio versus evolucao da profundidade foram estudadas em cristais PZN-4,5%PT, com diferentes orientacoes atraves da PFM. Padroes de dominio irregulares com tamanhos tipicos de 20-100 nm foram observados nas superficies com orientacao das amostras unpoled?. Pelo contrario, os cortes de cristal exibem dominios regulares de tamanho micron normal, com os limites do dominio orientados ao longo dos planos cristalograficos permitidos. A existencia de nanodominios em cristais com orientacao esta provisoriamente (wrong Word) atribuida a natureza relaxor de PZN-PT, onde pequenos grupos polares podem formar-se em coindicoes de zero-field-cooling (ZFC). Estes nanodominios sao considerados como os nucleos do estado de polarizacao oposta e podem ser responsaveis pelo menor campo coercitivo para este corte de cristal em particular. No entanto, a histerese local piezoeletrica realizada pelo PFM a escala nanometrica indica uma mudanca de comportamento de PZN-PT semelhante para ambas as orientacoes cristalograficas investigadas. A evolucao das estruturas de dominio com polimento abaixo da superficie do cristal foi investigada. O dominio de ramificacoes e os efeitos de polarizacao de triagem apos o polimento e as medicoes de temperatura tem sido estudados pela PFM e pela analise SEM. Alem disso, verificou-se que a intensidade do sinal piezoelectrico a partir das estruturas de nanodominio diminui com o aumento da temperatura, acabando por desaparecer aos 430 K (orientacao ) e 470 K (orientacao ). Esta diferenca de temperatura nas transicoes de fase local em cristais de diferentes orientacoes e explicada pelo forte efeito de superficie na transicao da fase ferroeletrica em relaxors. A comutacao da polarizacao em relaxor ergodico e nas fases ferroelectricas do sistema PMN-PT foram realizadas pela combinacao de tres metodos, Microscopia de Forca Piezoelectrica, medicao de um unico ponto de relaxamento eletromecânico e por ultimo mapeamento de espectroscopia de tensao. A dependencia do comportamento do relaxamento na amplitude e tempo da tensao de pulso foi encontrada para seguir um comportamento logaritmico universal com uma inclinacao quase constante. Este comportamento e indicativo da progressiva populacao dos estados de relaxamento lento, ao contrario de uma relaxacao linear na presenca de uma ampla distribuicao do tempo de relaxamento. O papel do comportamento de relaxamento, da nao-linearidade ferroelectrica e da heterogeneidade espacial do campo na ponta da sonda de AFM sobre o comportamento do ciclo de histerese e analisada em detalhe. Os ciclos de histerese para ergodica PMN- 10%PT sao mostrados como cineticamente limitados, enquanto que no PMN, com maior teor de PT, sao observados verdadeiros ciclos de histerese ferroelectrica com vies de baixa nucleacao.

  18. The Effect of Oxygen Supply on the Dual Growth Kinetics of Acidithiobacillus thiooxidans under Acidic Conditions for Biogas Desulfurization

    PubMed Central

    Namgung, Hyeong-Kyu; Song, JiHyeon

    2015-01-01

    In this study, to simulate a biogas desulfurization process, a modified Monod-Gompertz kinetic model incorporating a dissolved oxygen (DO) effect was proposed for a sulfur-oxidizing bacterial (SOB) strain, Acidithiobacillus thiooxidans, under extremely acidic conditions of pH 2. The kinetic model was calibrated and validated using experimental data obtained from a bubble-column bioreactor. The SOB strain was effective for H2S degradation, but the H2S removal efficiency dropped rapidly at DO concentrations less than 2.0 mg/L. A low H2S loading was effectively treated with oxygen supplied in a range of 2%–6%, but a H2S guideline of 10 ppm could not be met, even with an oxygen supply greater than 6%, when the H2S loading was high at a short gas retention time of 1 min and a H2S inlet concentration of 5000 ppm. The oxygen supply should be increased in the aerobic desulfurization to meet the H2S guideline; however, the excess oxygen above the optimum was not effective because of the decline in oxygen efficiency. The model estimation indicated that the maximum H2S removal rate was approximately 400 ppm/%-O2 at the influent oxygen concentration of 4.9% under the given condition. The kinetic model with a low DO threshold for the interacting substrates was a useful tool to simulate the effect of the oxygen supply on the H2S removal and to determine the optimal oxygen concentration. PMID:25633028

  19. Comparative Analysis of Psychological, Hormonal, and Genetic Factors Between Burning Mouth Syndrome and Secondary Oral Burning.

    PubMed

    das Neves de Araújo Lima, Emeline; Barbosa, Natália Guimarães; Dos Santos, Ana Celly Souza; AraújoMouraLemos, Telma Maria; de Souza, Cleber Machado; Trevilatto, Paula Cristina; da Silveira, Ericka Janine Dantas; de Medeiros, Ana Miryam Costa

    2016-09-01

    The objective of this study was to evaluate the association between psychological, hormonal, and genetic factors with the development of burning mouth syndrome (BMS) and secondary oral burning (SOB) in order to provide a better characterization and classification of these conditions. Cross sectional study. Patients with complaints of mouth burning registered at the Oral Diagnostic Service of the Federal University of Rio Grande do Norte between 2000 and 2013. The sample consisted of 163 subjects divided into a group of patients with BMS (n = 64) and a group of subjects with SOB (n = 99). The following variables were analyzed: passive and stimulated saliva flow, stress levels and phase, depression, anxiety, serum cortisol and dehydroepiandrosterone (DHEA) levels, and the presence of polymorphisms in the interleukin 6 (IL-6) gene. The results showed significant differences in the presence of xerostomia (p = 0.01), hyposalivation at rest (p < 0.001) and symptoms of depression (p = 0.033) between the two groups, which were more prevalent in the BMS group. DHEA levels were lower in the BMS group (p = 0.003) and were sensitive and specific for the diagnosis of this condition. Genetic analysis revealed no significant association between the polymorphisms analyzed and the development of BMS. These results suggest a possible role of depression, as well as of reduced DHEA levels, as associated factors for development of BMS. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Fate of colloids during estuarine mixing in the Arctic

    NASA Astrophysics Data System (ADS)

    Pokrovsky, O. S.; Shirokova, L. S.; Viers, J.; Gordeev, V. V.; Shevchenko, V. P.; Chupakov, A. V.; Vorobieva, T. Y.; Candaudap, F.; Causserand, C.; Lanzanova, A.; Zouiten, C.

    2014-02-01

    The estuarine behavior of organic carbon (OC) and trace elements (TE) was studied for the largest European sub-Arctic river, which is the Severnaya Dvina; this river has a deltaic estuary covered in ice during several hydrological seasons: summer (July 2010, 2012) and winter (March 2009) baseflow, and the November-December 2011 ice-free period. Colloidal forms of OC and TE were assessed for three pore size cutoffs (1, 10, and 50 kDa) using an in situ dialysis procedure. Conventionally dissolved (< 0.22 μm) fractions demonstrated clear conservative behavior for Li, B, Na, Mg, K, Ca, Sr, Mo, Rb, Cs, and U during the mixing of freshwater with the White Sea; a significant (up to a factor of 10) concentration increase occurs with increases in salinity. Si and OC also displayed conservative behavior but with a pronounced decrease in concentration seawards. Rather conservative behavior, but with much smaller changes in concentration (variation within ±30%) over a full range of salinities, was observed for Ti, Ni, Cr, As, Co, Cu, Ga, Y, and heavy REE. Strong non-conservative behavior with coagulation/removal at low salinities (< 5‰) was exhibited by Fe, Al, Zr, Hf, and light REE. Finally, certain divalent metals exhibited non-conservative behavior with a concentration gain at low (~ 2-5‰, Ba, Mn) or intermediate (~ 10-15‰, Ba, Zn, Pb, Cd) salinities, which is most likely linked to TE desorption from suspended matter or sediment outflux. The most important result of this study is the elucidation of the behavior of the "truly" dissolved low molecular weight LMW< 1 kDa fraction containing Fe, OC, and a number of insoluble elements. The concentration of the LMW fraction either remains constant or increases its relative contribution to the overall dissolved (< 0.22 μm) pool as the salinity increases. Similarly, the relative proportion of colloidal (1 kDa-0.22 μm) pool for the OC and insoluble TE bound to ferric colloids systematically decreased seaward, with the largest decrease occurring at low (< 5‰) salinities. Overall, the observed decrease in the colloidal fraction may be related to the coagulation of organo-ferric colloids at the beginning of the mixing zone and therefore the replacement of the HMW1 kDa-0.22 μm portion by the LMW< 1 kDa fraction. These patterns are highly reproducible across different sampling seasons, suggesting significant enrichment of the mixing zone by the most labile (and potentially bioavailable) fraction of the OC, Fe and insoluble TE. The size fractionation of the colloidal material during estuarine mixing reflects a number of inorganic and biological processes, the relative contribution of which to element speciation varies depending on the hydrological stage and time of year. In particular, LMW< 1 kDa ligand production in the surface horizons of the mixing zone may be linked to heterotrophic mineralization of allochthonous DOM and/or photodestruction. Given the relatively low concentration of particulate versus dissolved load of most trace elements, desorption from the river suspended material was less pronounced than in other rivers in the world. As a result, the majority of dissolved components exhibited either conservative (OC and related elements such as divalent metals) or non-conservative, coagulation-controlled (Fe, Al, and insoluble TE associated with organo-ferric colloids) behavior. The climate warming at high latitudes is likely to intensify the production of LMW< 1 kDa organic ligands and the associated TE; therefore, the delivery of potentially bioavailable trace metal micronutrients from the land to the ocean may increase.

  1. Characterization of biomasses, concentrates, and permeates of dried powder of Kombucha fermentation of spinach (Amaranthus sp.) and broccoli (Brassica oleracea) with membrane microfiltration and freeze drying techniques for natural sources of folic acid

    NASA Astrophysics Data System (ADS)

    Nugraha, Tutun; Susilowati, Agustine; Aspiyanto, Lotulung, Puspa Dewi; Maryati, Yati

    2017-11-01

    Fermentation of spinach (Amaranthus sp) and Broccoli (Brassica oleracea) using Kombucha Culture has been shown to produce biomass that has the potential to become natural sources of folic acid. To produce the materials, following the fermentation, the biomass was filtered using membrane microfiltration (0.15 µm) at a pressure of 40 psia, at room temperature, yielding the concentrate and the permeate fractions. Following this step, freeze drying process was done on the biomass feeds, as well as on the concentrate and permeate fractions. For the freeze drying stage, the samples were frozen, and the condenser was kept at -50°C for 40 hours, while the pressure in the chamber was set at 200 Pa. Freeze drying results showed that the final products, have differences in compositions, as well as differences in the dominat monomers of folates. After water content was driven out, freeze drying increased the concentrations of folic acid in the dried products, and was found to be the highest in the concentrate fractions. Freeze drying has been shown to be capable of protecting the folates from heat and oxidative damages that typicaly occur with other types of drying. The final freeze dried concentrates of fermentation of spinach and broccoli were found to contain folic acid at 2531.88 µg/mL and 1626.94 µg/mL, total solids at 87.23% and 88.65 %, total sugar at 22.66 µg/mL and 25.13 µg/mL, total reducing sugar at 34.46 mg/mL and 15.22 mg/mL, as well as disolved protein concentrations at 0.93 mg/mL and 1.45 mg/mL. Liquid Chromatography Mass Spectometry (LC-MS) identification of the folates in the freeze dried concentrates of fermented spinach and broccoli was done using folic acid and glutamic acid standard solutions as the reference materials. The results showed the presence of folic acid and showed that the dominant monomers of molecules of folates with molecular weights of 441.44 Da. and 441.54 Da. for spinach and broccoli respectively. Moreover, the monomers of glutamic acid were also found at molecular weights of 147.21 Da. and 147.35 Da. for spinach and broccoli respectively. Thus, it has been shown that kombucha fermentation of spinach and broccoli, followed by membrane microfiltration and freeze drying process, could produce dried materials with high concentrations of folates that have the potential to be used as naturally derived sources of folic acid.

  2. Single-protein detection in crowded molecular environments in cryo-EM images

    PubMed Central

    Rickgauer, J Peter; Grigorieff, Nikolaus; Denk, Winfried

    2017-01-01

    We present an approach to study macromolecular assemblies by detecting component proteins’ characteristic high-resolution projection patterns, calculated from their known 3D structures, in single electron cryo-micrographs. Our method detects single apoferritin molecules in vitreous ice with high specificity and determines their orientation and location precisely. Simulations show that high spatial-frequency information and—in the presence of protein background—a whitening filter are essential for optimal detection, in particular for images taken far from focus. Experimentally, we could detect small viral RNA polymerase molecules, distributed randomly among binding locations, inside rotavirus particles. Based on the currently attainable image quality, we estimate a threshold for detection that is 150 kDa in ice and 300 kDa in 100 nm thick samples of dense biological material. DOI: http://dx.doi.org/10.7554/eLife.25648.001 PMID:28467302

  3. Harmony search optimization in dimensional accuracy of die sinking EDM process using SS316L stainless steel

    NASA Astrophysics Data System (ADS)

    Deris, A. M.; Zain, A. M.; Sallehuddin, R.; Sharif, S.

    2017-09-01

    Electric discharge machine (EDM) is one of the widely used nonconventional machining processes for hard and difficult to machine materials. Due to the large number of machining parameters in EDM and its complicated structural, the selection of the optimal solution of machining parameters for obtaining minimum machining performance is remain as a challenging task to the researchers. This paper proposed experimental investigation and optimization of machining parameters for EDM process on stainless steel 316L work piece using Harmony Search (HS) algorithm. The mathematical model was developed based on regression approach with four input parameters which are pulse on time, peak current, servo voltage and servo speed to the output response which is dimensional accuracy (DA). The optimal result of HS approach was compared with regression analysis and it was found HS gave better result y giving the most minimum DA value compared with regression approach.

  4. Detection of platinum species in plant material.

    PubMed

    Messerschmidt, J; Alt, F; Tölg, G

    1995-05-01

    Model experiments for the detection of platinum species in extracts from native and platinum-treated grass cultivations are described. The procedural steps are cultivation of the grass samples, extraction and concentration of the platinum species by ultrafiltration and freeze-drying, preparative separation of the species by gel chromatography followed by isotachophoresis, and sequential analytical detection of the separated platinum species by adsorptive voltammetry. After isotachophoresis, sharp peaks of platinum species could be detected. In the native grass extract only one platinum species (160-200 kDa) was found. In the platinum-treated grass extracts several platinum species were observed in the molecular mass range from 1 to > 1000 kDa. By an extremely sensitive platinum determination method (adsorptive voltammetry; detection limit, 2 pg Pt abs.) it was possible to detect platinum even in stained protein bands from horizontal gel electrophoresis of platinum containing fractions obtained after isotachophoresis.

  5. Polymeric efficiency in remove impurities during cottonseed biodiesel production

    NASA Astrophysics Data System (ADS)

    Lin, H. L.; Liang, Y. H.; Yan, J.; Lin, H. D.; Espinosa, A. R.

    2016-07-01

    This paper describes a new process for developing biodiesel by polymer from crude cottonseed oil. The study was conducted to examine the effectiveness of the alkali transesterification-flocculation-sedimentation process on fast glycerol and other impurities in the separation from biodiesel by using quaternary polyamine-based cationic polymers SL2700 and polyacylamide cationic polymer SAL1100. The settling velocity of glycerol and other impurities in biodiesel was investigated through settling test experiments; the quality of the biodiesel was investigated by evaluating the viscosity and density. The results revealed that SL2700, SAL1100 and their combination dramatically improved the settling velocity of glycerol and other impurities materials than traditional method. SL 2700 with molecular weight of 0.2 million Da and charge density of 50% then plus SAL1100 with molecular weight of 11 million Da and charge density of 10% induced observable particle aggregation with the best settling performance.

  6. Propaganda and Philanthropy: The Institute Bento da Rocha Cabral, the Lisbon Site of Biochemistry (1925-1953).

    PubMed

    Carneiro, Ana; Amaral, Isabel

    2015-05-01

    This paper focuses on the internal organization and dynamics of the Institute Bento da Rocha Cabral (IRC) in Lisbon, a privately-funded institution devoted to biomedical research, from the particular vantage point of its laboratory of biochemistry; in particular, the process through which the institution turned from medically-related to chemically-related research in the period spanning from 1925 to 1953. The history of the IRC raises interesting questions regarding the social politics of science as it materialized the desire of leading physicians of the Faculty of Medicine of Lisbon to create proper physical facilities for medically-related scientific research. We argue that the process which led to the creation of the IRC coincided with the gradual professional and political ascendance of physicians in Portuguese society initiated in the late nineteenth century, and is closely associated with Portuguese republicanism and the process of Lisbon becoming the scientific capital.

  7. Biomarkers of Aspergillus spores

    NASA Astrophysics Data System (ADS)

    Sulc, Miroslav; Peslova, Katerina; Zabka, Martin; Hajduch, Marian; Havlicek, Vladimir

    2009-02-01

    We applied both matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometric and 1D sodium dodecylsulfate polyacrylamide gel electrophoretic (1D-PAGE) approaches for direct analysis of intact fungal spores of twenty four Aspergillus species. In parallel, we optimized various protocols for protein extraction from Aspergillus spores using acidic conditions, step organic gradient and variable sonication treatment. The MALDI-TOF mass spectra obtained from optimally prepared samples provided a reproducible fingerprint demonstrating the capability of the MALDI-TOF approach to type and characterize different fungal strains within the Aspergillus genus. Mass spectra of intact fungal spores provided signals mostly below 20 kDa. The minimum material amount represented 0.3 [mu]g (10,000 spores). Proteins with higher molecular weight were detected by 1D-PAGEE Eleven proteins were identified from three selected strains in the range 5-25 kDa by the proteomic approach. Hemolysin and hydrophobin have the highest relevance in host-pathogen interactions.

  8. Evaluation of saffron (Crocus sativus L.) adulteration with plant adulterants by (1)H NMR metabolite fingerprinting.

    PubMed

    Petrakis, Eleftherios A; Cagliani, Laura R; Polissiou, Moschos G; Consonni, Roberto

    2015-04-15

    In the present work, a preliminary study for the detection of adulterated saffron and the identification of the adulterant used by means of (1)H NMR and chemometrics is reported. Authentic Greek saffron and four typical plant-derived materials utilised as bulking agents in saffron, i.e., Crocus sativus stamens, safflower, turmeric, and gardenia were investigated. A two-step approach, relied on the application of both OPLS-DA and O2PLS-DA models to the (1)H NMR data, was adopted to perform authentication and prediction of authentic and adulterated saffron. Taking into account the deficiency of established methodologies to detect saffron adulteration with plant adulterants, the method developed resulted reliable in assessing the type of adulteration and could be viable for dealing with extensive saffron frauds at a minimum level of 20% (w/w). Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. The removal of hydrogen sulfide from biogas in a microaerobic biotrickling filter using polypropylene carrier as packing material.

    PubMed

    Zhou, Qiying; Liang, Hong; Yang, Senlin; Jiang, Xia

    2015-04-01

    Biological removal of hydrogen sulfide in biogas is an increasingly adopted alternative to the conventional physicochemical processes, because of its economic and environmental benefits. In this study, a microaerobic biofiltration system packed with polypropylene carrier was used to investigate the removal of high concentrations of H2S contained in biogas from an anaerobic digester. The results show that H2S in biogas was removed completely under different inlet concentrations of H2S from 2065 ± 234 to 7818 ± 131 ppmv, and the elimination capacity of H2S in the filter achieved about 122 g H2S/m(3)/h. It was observed that the content of CH4 in biogas increased after the biogas biodesulfurization process, which was beneficial for the further utilization of biogas. The elemental sulfur and sulfate were the main sulfur species of H2S degradation, and elemental sulfur was dominant (about 80 %) under high inlet H2S concentration. The results of terminal restriction fragment length polymorphism (T-RFLP) and fluorescence in situ hybridization (FISH) show that the population of sulfide-oxidizing bacteria (SOB) species in the filter changed with different concentrations of H2S. The microaerobic biofiltration system allows the potential use of biogas and the recovery of elemental sulfur resource simultaneously.

  10. ISOLATION, CHARACTERIZATION AND IMMUNOCHEMICAL STUDIES ON FIBROUS PROTEINS FROM COWRY SHELL (CYPRAEA MONETA, LINNAEUS)

    PubMed Central

    Togun, R.A.; Balogun, R. O.; Adeyemi, D.O.; Esan, T.A.; Oyatogun, G.M; Oziegbe, E.O; Okonji, R. E.; Kuku, A.

    2017-01-01

    Background: Biomaterials are non-drug substances used to treat, enhance or replace functions of body tissues or organs. Natural sources of biomaterials have recently become the focus of several research activities. Cowry shell constitutes one of the most promising natural sources of biomaterials because of its chemical stability, biodegradability and biocompatibility in the body. However, its applications may be limited due to immunogenic and toxic responses that may occur following implantation, hence this study. Materials and Methods: Crude fibrous protein extracted with citrate buffer from pulverised cowry shells (Cypraea moneta (L)), was resolved into two components (CSP1 and CSP2) by gel filtration. Immunological studies were performed with antisera obtained from rabbits by double immunodiffusion and immunoelectrophoresis techniques. Mice treated with the proteins were observed for signs of toxicity and their liver, kidney, lungs and spleen were processed histologically. Results: The native molecular weight of CSP1 and CSP2 determined by gel filtration were 91kDa and 33kDa respectively. CSP1 and CSP2 displayed single bands on SDS-PAGE with subunit molecular weight values of 19kDa and 19.5kDa respectively. Antisera obtained from rabbits immunised with the crude citrate buffer extracts precipitated the antigen in double immunodiffusion tests. Histopathological examinations revealed a dose-dependent damaging effect of the shell proteins on liver, kidney, lung and spleen tissues of the treated mice. Conclusion: This study showed that cowry shells contain fibrous proteins which are immunogenic and toxic in mice at relatively high concentrations, causing visible organ damage without concurrent physical manifestations. PMID:28480388

  11. Size distribution effects of cadmium tellurium quantum dots (CdS/CdTe) immunotoxicity on aquatic organisms.

    PubMed

    Bruneau, A; Fortier, M; Gagne, F; Gagnon, C; Turcotte, P; Tayabali, A; Davis, T L; Auffret, M; Fournier, M

    2013-03-01

    The increasing use of products derived from nanotechnology has raised concern about their potential toxicity to aquatic life. This study sought to examine the comparative immunotoxicity of capped cadmium sulphide/cadmium telluride (CdS/CdTe) quantum dots (QDs) and possible impact of particle/aggregate size on two bivalves (Mytilus edulis and Elliptio complanata) and a fish (Oncorhynchus mykiss). The QDs were dispersed in sterile water and fractionated using a series of micro/ultrafiltration membranes of decreasing pore size: 450 nm, 100 nm, 50 nm, 25 nm, 100 kDa (6.8 nm), 30 kDa (4.6 nm), 10 kDa (3.2 nm) and 1 kDa (1.5 nm). The total concentrations of cadmium and tellurium were determined for the filtered material and for that retained on the filters (retentate). The immunotoxicity was determined by measuring cell viability and phagocytosis. Results revealed that nanoparticles retained on the ultrafilters had a higher Cd/Te ratio compared to the permeate fraction (ratio of 5 and 2 respectively) which could indicate that the CdS core was not associated with the permeable fraction of Cd. Our results demonstrate that the toxicity of CdS/CdTe QDs was concentration and size dependent. Large CdS/CdTe QD aggregates (25 nm < size < 100 nm) reduced phagocytosis more than did smaller nanoparticles (<25 nm). Moreover, our results revealed that the different species responded differently to these fractions. Mytilus edulis hemocytes were less sensitive to CdS/CdTe QDs than the Oncorhynchus mykiss macrophage and Elliptio complanata hemocytes.

  12. The Scl1 protein of M6-type group A Streptococcus binds the human complement regulatory protein, factor H, and inhibits the alternative pathway of complement.

    PubMed

    Caswell, Clayton C; Han, Runlin; Hovis, Kelley M; Ciborowski, Pawel; Keene, Douglas R; Marconi, Richard T; Lukomski, Slawomir

    2008-02-01

    Non-specific activation of the complement system is regulated by the plasma glycoprotein factor H (FH). Bacteria can avoid complement-mediated opsonization and phagocytosis through acquiring FH to the cell surface. Here, we characterize an interaction between the streptococcal collagen-like protein Scl1.6 of M6-type group A Streptococcus (GAS) and FH. Using affinity chromatography with immobilized recombinant Scl1.6 protein, we co-eluted human plasma proteins with molecular weight of 155 kDa, 43 kDa and 38 kDa. Mass spectrometry identified the 155 kDa band as FH and two other bands as isoforms of the FH-related protein-1. The identities of all three bands were confirmed by Western immunoblotting with specific antibodies. Structure-function relation studies determined that the globular domain of the Scl1.6 variant specifically binds FH while fused to collagenous tails of various lengths. This binding is not restricted to Scl1.6 as the phylogenetically linked Scl1.55 variant also binds FH. Functional analyses demonstrated the cofactor activity of the rScl1.6-bound FH for factor I-mediated cleavage of C3b. Finally, purified FH bound to the Scl1.6 protein present in the cell wall material obtained from M6-type GAS. In conclusion, we have identified a functional interaction between Scl1 and plasma FH, which may contribute to GAS evasion of complement-mediated opsonization and phagocytosis.

  13. Diffusion of Na(I), Cs(I), Sr(II) and Eu(III) in smectite rich natural clay.

    PubMed

    Kasar, Sharayu; Kumar, Sumit; Bajpai, R K; Tomar, B S

    2016-01-01

    Diffusion of Na(I), Cs(I), Sr(II) and Eu(III) in smectite rich natural clay, proposed as a backfill material in the Indian geological repository, was studied using the out-diffusion method. Radiotracers (22)Na, (137)Cs, (85)Sr and (154)Eu were used; the first three are carrier-free enabling experimental work at sub-micromolar metal ion concentration, and Eu(III) tracer (154)Eu was used at sub millimolar concentration. An out-diffusion methodology, wherein a thin planar source of radioactivity placed between two clay columns diffuses out, was used to obtain the apparent diffusion coefficient (Da) values. This methodology enabled determination of diffusion coefficient even for strongly sorbing (154)Eu. Da values for (22)Na, (137)Cs, (85)Sr and (154)Eu were 2.35 (±0.14) × 10(-11), 2.65 (±0.09) × 10(-12), 3.32 (±0.15) × 10(-11) and 1.23 (±0.15) × 10(-13) m(2) s(-1), respectively. Da values were found to be in fair agreement with literature data reported for similar mineralogical sediments. Sorption of radionuclides on the clay was also determined in the present study and differences in Da values were rationalized on the basis of sorption data. Distribution ratios (Kd) for Cs(I) and Eu(III) were higher than that for Sr(II), which in turn was higher than that for Na(I). Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Simultaneous electrochemical detection of dopamine and uric acid over ceria supported three dimensional gold nanoclusters

    NASA Astrophysics Data System (ADS)

    Palanisamy, Sivakumar

    2014-12-01

    CeO2 is well known for being an active material to support the growth of Au nanoclusters (Au NCs). In this work, three dimensional (3D) Au NCs were deposited on three different shaped CeO2 nanostructures such as nanoparticles (NPs), nanorod arrays (NRAs) and nanoflowers (NFs) modified Ti substrate for electrochemical simultaneous detection of dopamine (DA) and uric acid (UA). The electrodeposition of 3D Au NCs were carried out via cyclic voltammetric (CV) method at over-potential, while CeO2 nanostructures were deposited by galvanostatic constant current method under the optimized conditions. The morphology and elemental composition analysis of 3D Au NCs with CeO2 nanostructures were characterized by SEM, XRD, XPS and EDAX measurements. The electrocatalytic activity of 3D Au NCs on different CeO2 supports were thoroughly investigated by using voltammetric and amperometric techniques. According to the obtained results, CeO2 NPs supported 3D Au NCs (3D Au NCs@CeO2 NPs) displayed strong signal for DA as compared to that of CeO2 NRAs (3D Au NCs@CeO2 NRAs) and CeO2 NFs supported 3D Au NCs (3D Au NCs@CeO2 NFs). In addition, the 3D Au NCs@CeO2 NPs electrode resulted in more sensitive and simultaneous detection of DA in the presence of excess UA. Thus, the 3D Au NCs@CeO2 NPs electrode can practically be applied for the detection of DA using biological samples.

  15. Novel Diels-Alder based self-healing epoxies for aerospace composites

    NASA Astrophysics Data System (ADS)

    Coope, T. S.; Turkenburg, D. H.; Fischer, H. R.; Luterbacher, R.; van Bracht, H.; Bond, I. P.

    2016-08-01

    Epoxy resins containing Diels-Alder (DA) furan and maleimide moieties are presented with the capability to self-heal after exposure to an external heat source. A conventional epoxy amine system has been combined with furfuryl and maleimide functional groups in a two-step process, to avoid major side-reactions, and the concentration of a thermo-reversibly binding cross-linker was considered to balance thermoset and thermoplastic behaviours, and the subsequent self-healing performance. In the context of self-repair technologies an inbuilt ‘intrinsic’ self-healing system is deemed favourable as the healing agent can be placed in known ‘hot spot’ regions (i.e. skin-stringer run outs, ply drops and around drilled holes) where operational damage predominately occurs in load bearing aerospace structures. In this study, the mechanical and self-healing performance of furan functionalised epoxy resins containing varying amounts (10, 20, 30 or 40 pph) of bismaleimide were investigated using a bulk epoxy polymer tapered double cantilever beam test specimen geometry. Two forms, a thin film and a bulk material, were evaluated to account for future integration methods into fibre reinforced polymer (FRP) composites. The highest healing efficiency, with respect to the obtained initial load value, was observed from the 20 pph bulk material derivative. The polymers were successful in achieving consistent multiple (three) healing cycles when heated at 150 °C for 5 min. This novel investigated DA material exhibits favourable processing characteristics for FRP composites as preliminary studies have shown successful coextrution with reinforcing fibres to form free standing films and dry fibre impregnation.

  16. Porphyry-Style Petropavlovskoe Gold Deposit, the Polar Urals: Geological Position, Mineralogy, and Formation Conditions

    NASA Astrophysics Data System (ADS)

    Vikentyev, I. V.; Mansurov, R. Kh.; Ivanova, Yu. N.; Tyukova, E. E.; Sobolev, I. D.; Abramova, V. D.; Vykhristenko, R. I.; Trofimov, A. P.; Khubanov, V. B.; Groznova, E. O.; Dvurechenskaya, S. S.; Kryazhev, S. G.

    2017-11-01

    Geological and structural conditions of localization, hydrothermal metasomatic alteration, and mineralization of the Petropavlovskoe gold deposit (Novogodnenskoe ore field) situated in the northern part of the Lesser Ural volcanic-plutonic belt, which is a constituent of the Middle Paleozoic island-arc system of the Polar Urals, are discussed. The porphyritic diorite bodies pertaining to the late phase of the intrusive Sob Complex play an ore-controlling role. The large-volume orebodies are related to the upper parts of these intrusions. Two types of stringer-disseminated ores have been revealed: (1) predominant gold-sulfide and (2) superimposed low-sulfide-gold-quartz ore markedly enriched in Au. Taken together, they make up complicated flattened isometric orebodies transitory to linear stockworks. The gold potential of the deposit is controlled by pyrite-(chlorite)-albite metasomatic rock of the main productive stage, which mainly develops in a volcanic-sedimentary sequence especially close to the contacts with porphyritic diorite. The relationships between intrusive and subvolcanic bodies and dating of individual zircon crystals corroborate a multistage evolution of the ore field, which predetermines its complex hydrothermal history. Magmatic activity of mature island-arc plagiogranite of the Sob Complex and monzonite of the Kongor Complex initiated development of skarn and beresite alterations accompanied by crystallization of hydrothermal sulfides. In the Early Devonian, due to emplacement of the Sob Complex at a depth of approximately 2 km, skarn magnetite ore with subordinate sulfides was formed. At the onset of the Middle Devonian, the large-volume gold porphyry Au-Ag-Te-W ± Mo,Cu stockworks related to quartz diorite porphyry—the final phase of the Sob Complex— were formed. In the Late Devonian, a part of sulfide mineralization was redistributed with the formation of linear low-sulfide quartz vein zones. Isotopic geochemical study has shown that the ore is deposited from reduced, substantially magmatic fluid, which is characterized by close to mantle values δ34S = 0 ± 1‰, δ13C =-6 to-7‰, and δ18O = +5‰ as the temperature decreases from 420-300°C (gold-sulfide ore) to 250-130°C (gold-(sulfide)-quartz ore) and pressure decreases from 0.8 to 0.3 kbar. According to the data of microanalysis (EPMA and LA-ICP-MS), the main trace elements in pyrite of gold orebodies are represented by Co (up to 2.52 wt %), As (up to 0.70 wt %), and Ni (up to 0.38 wt %); Te, Se, Ag, Au, Bi, Sb, and Sn also occur. Pyrite of the early assemblages is characterized by high Co, Te, Au, and Bi contents, whereas the late pyrite is distinguished by elevated concentrations of As (up to 0.7 wt %), Ni (up to 0.38 wt %), Se (223 ppm), Ag (up to 111 ppm), and Sn (4.4 ppm). The minimal Au content in pyrite of the late quartz-carbonate assemblage is up to 1.7 ppm and geometric average is 0.3 ppm. The significant correlation between Au and As (furthermore, negative-0.6) in pyrite from ore of the Petropavlovskoe deposit is recorded only for the gold-sulfide assemblage, whereas it is not established for other assemblages. Pyrite with higher As concentration (up to 0.7 wt %) is distinguished only for the Au-Te mineral assemblage. Taking into account structural-morphological and mineralogical-geochemical features, the ore-magmatic system of the Petropavlovskoe deposit is referred to as gold porphyry style. Among the main criteria of such typification are the spatial association of orebodies with bodies of subvolcanic porphyry-like intrusive phases at the roof of large multiphase pluton; the stockwork-like morphology of gold orebodies; 3D character of ore-alteration zoning and distribution of ore components; geochemical association of gold with Ag, W, Mo, Cu, As, Te, and Bi; and predominant finely dispersed submicroscopic gold in ore.

  17. Mass balance of arsenic fluxes in rivers impacted by gold mining activities in Paracatu (Minas Gerais State, Brazil).

    PubMed

    Bidone, Edison; Cesar, Ricardo; Santos, Maria Carla; Sierpe, Ricardo; Silva-Filho, Emmanuel Vieira; Kutter, Vinicius; Dias da Silva, Lílian I; Castilhos, Zuleica

    2018-03-01

    Arsenic (As) is a dangerous and carcinogenic element and drinking water is its main pathway of human exposure. Gold mines are widely recognized as important sources of As pollution. This work proposes the assessment of As distribution along watersheds surrounding "Morro do Ouro" gold mine (Paracatu, southeastern Brazil). A balance approach between filtered As fluxes (As < 0.45 μm) and suspended particulate material (AsSPM) in different river segments was applied. Ultrafiltration procedure was used to categorize As into the following classes: particulate > 0.1 μm, colloidal < 0.1 μm to > 10 kDa, dissolved < 10 kDa to > 1 kDa, and truly dissolved < 1 kDa. By applying this approach, arsenic contributions from mining facilities were quantified in order to identify critical fluvial segments and support decision makers in actions of remediation. The mass balance indicated the occurrence of a decreasing gradient from upstream to downstream: (i) of the As concentrations higher than the limit established by Brazilian law (10 μg L -1 ); (ii) of the ratio between specific fluxes (g As km -2  day -1 ) and those determined using an uncontaminated watershed (a proxy for estimating the anthropic contribution), from 103 to 101; (iii) of the specific fluxes As < 0.45 μm and AsSPM from 102 to 100; and (iv) of the negative balance output minus input for each river segment that suggests As accumulation in sediments along the rivers in both urban and rural areas, mainly due to SPM sedimentation and sorption by Fe oxyhydroxides. Ultrafiltration shattering showed concentrations of decreasing As with particle size; the SPM load (> 0.1 μm) was almost one order higher to dissolved load (< 1 kDa).

  18. Purification and structure of human liver aspartylglucosaminidase.

    PubMed Central

    Rip, J W; Coulter-Mackie, M B; Rupar, C A; Gordon, B A

    1992-01-01

    We have recently diagnosed aspartylglucosaminuria (AGU) in four members of a Canadian family. AGU is a lysosomal storage disease in which asparagine-linked glycopeptides accumulate to particularly high concentrations in liver, spleen and thyroid of affected individuals. A lesser accumulation of these glycopeptides is seen in the kidney and brain, and they are also excreted in the urine. The altered metabolism in AGU results from a deficiency of the enzyme aspartylglucosaminidase (1-aspartamido-beta-N-acetylglucosamine amidohydrolase), which hydrolyses the asparagine to N-acetylglucosamine linkages of glycoproteins and glycopeptides. We have used human liver as a source of material for the purification of aspartylglucosaminidase. The enzyme has been purified to homogeneity by using heat treatment, (NH4)2SO4 fractionation, and chromatography on concanavalin A-Sepharose, DEAE-Sepharose, sulphopropyl-Sephadex, hydroxyapatite, DEAE-cellulose and Sephadex G-100. Enzyme activity was followed by measuring colorimetrically the N-acetylglucosamine released from aspartylglucosamine at 56 degrees C. The purified enzyme protein ran at a 'native' molecular mass of 56 kDa in SDS/12.5%-PAGE gels, and the enzyme activity could be quantitatively recovered at this molecular mass by using gel slices as enzyme source in the assay. After denaturation by boiling in SDS the 56 kDa protein was lost with the corresponding appearance of polypeptides alpha,beta and beta 1, lacking enzyme activity, at 24.6, 18.4 and 17.4 kDa respectively. Treatment of heat-denatured enzyme with N-glycosidase F resulted in the following decreases in molecular mass; 24.6 to 23 kDa and 18.4 and 17.4 to 15.8 kDa. These studies indicate that human liver aspartylglucosaminidase is composed of two non-identical polypeptides, each of which is glycosylated. The N-termini of alpha,beta and beta 1 were directly accessible for sequencing, and the first 21, 26 and 22 amino acids respectively were identified. Images Fig. 4. Fig. 7. Fig. 8. PMID:1281977

  19. The adenosine A2A antagonist MSX-3 reverses the effort-related effects of dopamine blockade: differential interaction with D1 and D2 family antagonists

    PubMed Central

    Worden, Lila T.; Shahriari, Mona; Farrar, Andrew M.; Sink, Kelly S.; Hockemeyer, Jörg; Müller, Christa E.

    2010-01-01

    Rationale Brain dopamine (DA) participates in the modulation of instrumental behavior, including aspects of behavioral activation and effort-related choice behavior. Rats with impaired DA transmission reallocate their behavior away from food-seeking behaviors that have high response requirements, and instead select less effortful alternatives. Although accumbens DA is considered a critical component of the brain circuitry regulating effort-related choice behavior, emerging evidence demonstrates a role for adenosine A2A receptors. Objective Adenosine A2A receptor antagonism has been shown to reverse the effects of DA antagonism. The present experiments were conducted to determine if this effect was dependent upon the subtype of DA receptor that was antagonized to produce the changes in effort-related choice. Materials and methods The adenosine A2A receptor antagonist MSX-3 (0.5–2.0 mg/kg IP) was assessed for its ability to reverse the effects of the D1 family antagonist SCH39166 (ecopipam; 0.2 mg/kg IP) and the D2 family antagonist eticlopride (0.08 mg/kg IP), using a concurrent lever pressing/chow feeding procedure. Results MSX-3 produced a substantial dose-related reversal of the effects of eticlopride on lever pressing and chow intake. At the highest dose of MSX-3, there was a complete reversal of the effects of eticlopride on lever pressing. In contrast, MSX-3 produced only a minimal attenuation of the effects of SCH39166, as measured by regression and effect size analyses. Conclusions The greater ability of MSX-3 to reverse the effects of D2 vs. D1 blockade may be related to the colocalization of D2 and adenosine A2A receptors on the same population of striatal neurons. PMID:19048234

  20. On the surface chemistry of molybdena-alumina catalysts prepared from Mo(CO) sub 6

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goldwasser, J.; Fang, S.M.; Houalla, M.

    1989-01-01

    Catalysts were prepared by subliming Mo(CO){sub 6} onto partially dehydroxylated (PDA) and exhaustively dehydroxylated (DA) alumina made from the same parent preparation (American Cyanamid Aero 100PHF). The chemisorption of NO and Co on these materials was studied using volumetric, chromatographic, and spectroscopic techniques. ESCA data indicated that metallic Mo crystals formed on Mo(CO){sub 6}/DA whereas on PDA both Mo{sup 4+} and some lower valence state, Mo{sup 2+} or Mo{sup 0}, were present. NO chemisorbed on both preparations at 195 K without releasing either N{sub 2}O or N{sub 2}. The chemisorption on the PDA preparations was over tenfold higher than thatmore » on the DA-supported catalysts under these conditions, but at 300 K the difference was reduced to a factor of 2. Moreover, redox chemistry occurred at this higher temperature as evidenced by the release of N{sub 2}O and N{sub 2}. The amounts of NO actually chemisorbed correlated well with the integrated IR band intensities. These data suggest that lower valence states are oxidized to Mo{sup 4+} at 300 K and that the observed IR bands stem from Mo{sup 4+}(NO){sub 2}, irrespective of the initial catalyst. Infrared spectra from residual CO remaining on decomposition of Mo(CO){sub 6} on DA and PDA showed bands which could be attributed to residual Mo(CO){sub 6} and/or to subcarbonyl species formed during decomposition. By 573 K, no residual bands could be observed. On adding-back CO at 300 K to the PDA preparation, bands at 1989 and 2170 cm{sup {minus}1} appeared, suggesting the presence of Mo{sup 4+} and residual Mo{sup 0}. Spectra from similar experiments with the DA preparation demonstrated that chemisorbed Mo(CO){sub 6} was reforming and possibly some subcarbonyl species.« less

  1. Gas Separation Properties of Polyimide Thin Films on Ceramic Supports for High Temperature Applications

    PubMed Central

    Escorihuela, Sara; Brinkmann, Torsten

    2018-01-01

    Novel selective ceramic-supported thin polyimide films produced in a single dip coating step are proposed for membrane applications at elevated temperatures. Layers of the polyimides P84®, Matrimid 5218®, and 6FDA-6FpDA were successfully deposited onto porous alumina supports. In order to tackle the poor compatibility between ceramic support and polymer, and to get defect-free thin films, the effect of the viscosity of the polymer solution was studied, giving the entanglement concentration (C*) for each polymer. The C* values were 3.09 wt. % for the 6FDA-6FpDA, 3.52 wt. % for Matrimid®, and 4.30 wt. % for P84®. A minimum polymer solution concentration necessary for defect-free film formation was found for each polymer, with the inverse order to the intrinsic viscosities (P84® ≥ Matrimid® >> 6FDA-6FpDA). The effect of the temperature on the permeance of prepared membranes was studied for H2, CH4, N2, O2, and CO2. As expected, activation energy of permeance for hydrogen was higher than for CO2, resulting in H2/CO2 selectivity increase with temperature. More densely packed polymers lead to materials that are more selective at elevated temperatures. PMID:29518942

  2. Effect of rotary cutting instruments on the resin-tooth interfacial ultra structure: An in vivo study

    PubMed Central

    Sherawat, Sudhir; Tewari, Sanjay; Duhan, Jigyasa; Singla, Rakesh

    2014-01-01

    Objectives: To evaluate the effect of cutting teeth with different types of burs at various speeds on surface topography of tooth surface and interfacial gap formation at resin-tooth interface. Material and Methods: The human molars were divided into seven groups: Diamond bur in airrotor (DA) & micromotor (DM), crosscut carbide bur in airrotor (CCA) & micromotor (CCM), plain carbide bur in airrotor (CA) & micromotor (CM) and #600-grit silicon carbide paper (SiC). In five samples from each group Class II box-only cavities were restored. The occlusal surface of four teeth per group was flattened. Two out of four teeth were acid etched. Teeth were subjected for scanning electron microscopy (SEM). Results: Interfacial gap was observed in all groups with no significant difference. SEM observations revealed CA, CCA & DA were coarser than CM, CCM, DM and SiC. SEM of etched tooth surfaces revealed complete removal of amorphous smear layer in CA & CM, partial removal in CCA, CCM, DA & DM and no removal in SiC. Conclusions: Selecting an appropriate bur and its speed may not play an important role in bonding in terms of interfacial gap formation. Variable changes were observed in surface topography with different burs before and after acid etching. Key words:Surface topography, resin-tooth interface, interfacial gap, bonding. PMID:25674310

  3. Effect of Pre-Ozonation and UF Membrane Modification with CNT on Fouling Control

    NASA Astrophysics Data System (ADS)

    Wang, Kailun; Guan, Yuqi; Zhu, Xuedong; Dong, Dan; Guo, Jin

    2018-01-01

    The effect of carbon nanotubes (CNT) modification on ultrafiltration membrane fouling control was explored. Three kinds of base membrane were chosen in the study: 20 kDa polysulfone (PS) membrane, 20 kDa and 100 kDa polyethersulfone (PES) membrane. Besides, the effect of pre-ozonation on the three CNT modified membranes for fouling alleviation was further studied. CNT modification presented antifouling properties at the beginning of filtration, while the recoverability of the CNT modified membranes are relatively lower as for the blocking of CNT layer by foulants. Pre-ozonation with a lower ozone concentration (0.25 mgO3/mgDOC) did not efficiently alleviate the fouling of CNT modified membranes. With the ozone concentration increased to 0.81 mgO3/mgDOC, the CNT modified membranes exhibited their higher antifouling properties. Water quality analysis results showed that CNT modification presented a higher capture ability for the humic-like and protein-like substances. After pre-ozonation, more organic materials could be retained in the interior of CNT layer, which decreased the fouling of base membranes and increased the permeate quality as well. Base membrane with large molecular size cut-off is more helpful for the synergistic effect of pre-ozonation and CNT modification.

  4. Characterizing Novel Thermophilic Amylase Producing Bacteria From Taptapani Hot Spring, Odisha, India

    PubMed Central

    Sen, Sudip Kumar; Raut, Sangeeta; Satpathy, Soumya; Rout, Prangya Ranjan; Bandyopadhyay, Bidyut; Das Mohapatra, Pradeep Kumar

    2014-01-01

    Background: Amylases play a vital role in biotechnological studies and rank an important position in the world enzyme market (25% to 33%). Bioprocess method of amylase production is more effective than the other sources, since the technique is easy, cost effective, fast, and the enzymes of required properties can be procured. Objectives: The current study aimed to report the characteristics of novel amylase producing bacterial strains isolated from Taptapani hot spring, Odisha, India. Materials and Methods: Bacterial strains were isolated by dilution plating method from the water samples collected from Taptapani Hot Spring, Odisha and screened for amylase production through starch hydrolysis. The bacterial isolates were identified morphologically, biochemically, and finally by 16S rDNA profiling. Results: Based on the morphological, physiological, biochemical characteristics and the molecular characterization, the isolates SS1, SS2, and SS3 were identified as Bacillus barbaricus, Aeromonas veroni, and Stenotrophomonas maltophilia, respectively. The approximate molecular weight of enzymes from SS1, SS2, and SS3 strains were 19 kDa, 56 kDa and 49 kDa, respectively. Conclusions: The current report isolates, characterizes, and demonstrates the novel heat-adapted amylase-producing bacteria SS1, SS2 and SS3 from Taptapani hot spring, indicating its potentiality and stability under acidic conditions. PMID:25741425

  5. Robot-Assisted Laparoendoscopic Single-Site Partial Nephrectomy With the Novel Da Vinci Single-Site Platform: Initial Experience

    PubMed Central

    Komninos, Christos; Tuliao, Patrick; Kim, Dae Keun; Choi, Young Deuk; Chung, Byung Ha

    2014-01-01

    Purpose To report our initial clinical cases of robotic laparoendoscopic single-site (R-LESS) partial nephrectomy (PN) performed with the use of the novel Da Vinci R-LESS platform. Materials and Methods Three patients underwent R-LESS PN from November 2013 through February 2014. Perioperative and postoperative outcomes were collected and intraoperative difficulties were noted. Results Operative time and estimated blood loss volume ranged between 100 and 110 minutes and between 50 and 500 mL, respectively. None of the patients was transfused. All cases were completed with the off-clamp technique, whereas one case required conversion to the conventional (multiport) approach because of difficulty in creating the appropriate scope for safe tumor resection. No major postoperative complications occurred, and all tumors were resected in safe margins. Length of hospital stay ranged between 3 and 7 days. The lack of EndoWrist movements, the external collisions, and the bed assistant's limited working space were noticed to be the main drawbacks of this surgical method. Conclusions Our initial experience with R-LESS PN with the novel Da Vinci platform shows that even though the procedure is feasible, it should be applied in only appropriately selected patients. However, further improvement is needed to overcome the existing limitations. PMID:24955221

  6. High loading of uniformly dispersed Pt nanoparticles on polydopamine coated carbon nanotubes and its application in simultaneous determination of dopamine and uric acid

    NASA Astrophysics Data System (ADS)

    Lin, Mouhong; Huang, Haoliang; Liu, Yingju; Liang, Canjian; Fei, Shidong; Chen, Xiaofen; Ni, Chunlin

    2013-02-01

    Multiwalled carbon nanotubes (MWCNT) were homogeneously covered with a bio-functional polydopamine (PDOP) by a simple dip-coating approach in mild basic solution. Then, uniformly dispersed and highly loaded platinum nanoparticles (PtNPs) were deposited on MWCNT@PDOP by a mild reductant, and were characterized by transmission electron microscopy and x-ray photoelectron spectroscopy. Afterwards, this nanocomposite was modified on the glass carbon electrode and applied to simultaneously determine dopamine (DA) and uric acid (UA) by differential pulse voltammetry (DPV). Results showed that a linear electro-oxidation response was found for DA and UA in the range of 0.25-20 μM and 0.3-13 μM with the detection limit (S/N = 3) of 0.08 μM and 0.12 μM, respectively. In addition, the detection sensitivities for DA and UA by DPV were 1.03 μA μM-1 and 2.09 μA μM-1, respectively, which were much higher than those from a cyclic voltammogram. Finally, the reproducibility and stability of the nanocomposite were also evaluated, demonstrating that such MWCNT@PDOP@PtNPs can be a promising candidate for advanced electrode material in electrochemical sensing and other electrocatalytic applications.

  7. Comparison and extension of free dendritic growth models through application to silver-15 mass percent copper alloy

    NASA Astrophysics Data System (ADS)

    Onel, Selis

    Modeling free dendritic growth in supercooled alloys is a critical requirement in controlling the microstructure of materials during rapid solidification processing of materials. Recent models developed to predict the growth of a dendrite in a highly supercooled melt adopt modifications that account for the interface kinetics and thermodynamics at high interface velocities, but the assumptions necessary to simplify the mathematical problem impose inherent restrictions. The assumption of straight phase boundaries adopted in early models often loses validity at high supercoolings, where phase boundaries are often curved. The use of equations with Henrian restrictions, such as the Baker-Cahn equation for the interfacial driving force and the Aziz equation for solute trapping confine these models to dilute solutions. Turnbull's collision-limited linear kinetic equation for interface growth may not apply to large interfacial driving forces. Therefore, a useful application and modification of free dendritic growth models require a thorough understanding of their limitations in producing consistent results. One of the objectives of this research is to numerically compare the free dendritic growth models derived from the earlier LGK model developed by Lipton et al. The subsequent LKT model by Lipton et al., the TLK model by Trivedi et al., and the BCT model by Boettinger et al., together with a modification of the TLK model, and the DA model by DiVenuti and Ando are compared through application to an Ag-15 mass % Cu alloy. In addition, a new model to extend the DA model is developed by incorporating a thermodynamic solution model for the calculation of the interfacial driving force, thereby eliminating the Baker-Cahn equation that limits the use of the correct BCT and DA models to dilute solutions. Direct computation of the interfacial driving force by calculating a metastable phase diagram for the Ag-Cu system using a temperature dependent subregular solution model is carried out. Comparison of the results of the new model with the DA model confirms that the Baker-Cahn equation is applicable at low solute concentrations. As a future research direction, the new model can be extended to apply to higher concentration alloys by using a new solute trapping equation to further eliminate the dilute solution limitations.

  8. Non-Catalytic Reforming with Applications to Portable Power

    DTIC Science & Technology

    2013-10-01

    and J.J. Beaman, Jr., “Freeform Fabrication of Non-Metallic Objects by Selective Laser Sintering and Infiltration”, Materials Science Forum, 561-565...for syngas production from jet fuel using various methods including catalysts [4, 47-54] and plasmas [55]. Investigations of noncatalytic reforming...Combustion of n-butanol in a spark -ignition IC engine. Fuel. 89(7): p. 1573-1582. 32. Behrens, D.A., I.C. Lee, and C.M. Waits, Catalytic combustion of

  9. Modification of the supramolecular structure of collagen with nanodisperse hydroxyapatite

    NASA Astrophysics Data System (ADS)

    Voloskova, E. V.; Berdnikova, L. K.; Poluboyarov, V. A.; Gur'yanova, T. I.

    2015-02-01

    The influence of nanodisperse particles of hydroxyapatite on the structure of films based on collagen with a molecular mass of 360 kDa was studied. When coatings formed, the collagen macromolecules aggregated into spherulites; modification led to structural changes related to the decomposition of the spherulite structure and the formation of a grain structure. The variation of the physicomechanical properties of film materials directly depends on the size of the structural units.

  10. Center of Cardiac Surgery Robotic Computerized Telemanipulation as Part of a Comprehensive Approach to Advanced Heart Care

    DTIC Science & Technology

    2011-10-01

    performance metrics; and development of Robotic OR Team training including crisis management. Q3: During the third quarter of this project, the...literature review for robot-assisted surgical skill training/performance metrics; development of Robotic OR Team training materials including crisis ... crisis management situations. Q2: Contract negotiations for the purchase of the da Vinci Skills Simulator are completed and we anticipate the

  11. Safety and Immunogenicity Testing of a Pilot Polysaccharide Vaccine Preparation to Pseudomonas aeruginosa.

    DTIC Science & Technology

    1981-09-01

    8217-NAL." BUR-._,AL)- ’..O,.-,.S.AN--DA. .-D-S.... . . . .A AD___________ Safety and Immunogenicity Testing of a Pilot Polysaccharide Vaccine Preparation...COVERED Safety and Immunogenicity Testing of a Pilot Annual Report Polysaccharide Vaccine Preparation to (16 Aug. 80 - 1 Aug. 81) Pseudomonas...immunogenic or biologically active component of the vaccine. The vaccine is a high molecu- lar weight polysaccharide (PS) material isolated from the outer

  12. Photoaffinity labelling of cyclic GMP-inhibited phosphodiesterase (PDE III) in human and rat platelets and rat tissues: effects of phosphodiesterase inhibitors.

    PubMed

    Tang, K M; Jang, E K; Haslam, R J

    1994-06-15

    Ultraviolet irradiation of human platelet cytosol in the presence of 32P-labelled cyclic GMP (cGMP) can specifically label 110, 80, 55, 49 and 38 kDa proteins; the 110 kDa species is the subunit of cGMP-inhibited phosphodiesterase (PDE III) and the 80 kDa species that of cGMP-dependent protein kinase (Tang et al., 1993, Biochem. J. 294, 329). We have now shown that although photolabelling of platelet PDE III was inhibited by unlabelled cGMP, 8-bromo-cGMP and cyclic AMP (cAMP), it was not affected by phosphorothioate analogues of these cyclic nucleotides. Specific concentration-dependent inhibitions of the photolabelling of PDE III were observed with the following PDE inhibitors: trequinsin (IC50 = 13 +/- 2 nM), lixazinone (IC50 = 22 +/- 4 nM), milrinone (IC50 = 56 +/- 12 nM), cilostamide (IC50 = 70 +/- 9 nM), siguazodan (IC50 = 117 +/- 29 nM) and 3-isobutyl 1-methylxanthine (IBMX) (IC50 = 3950 +/- 22 nM). Thus, measurements of the inhibitory effects of compounds on the photolabelling of platelet PDE III provide a simple quantitative means of investigating their actions at a molecular level that avoids the need to purify the enzyme. Photolabelling of rat platelet lysate or rat heart homogenate by [32P]cGMP showed that the 110 kDa PDE III present in human material was replaced by a 115 kDa protein, labelling of which was also blocked by PDE III inhibitors. Heart and other rat tissues contained much less of this putative 115 kDa PDE III than rat platelets. In contrast, the 80 kDa protein was labelled much less in platelets than in many other rat tissue homogenates (e.g., heart, aorta, uterus and lung). Thus, comparison of the relative amounts of specific photolabelled proteins in different cells may provide an indication of different patterns of cyclic nucleotide action. We compared the abilities of phosphodiesterase inhibitors to block the photolabelling of PDE III in human platelet cytosol and to increase the iloprost-stimulated accumulation of cAMP in intact platelets. Whereas trequinsin (EC50 = 19 +/- 3 nM), lixazinone (EC50 = 122 +/- 8 nM), milrinone (EC50 = 5320 +/- 970 nM) and siguazodan (EC50 = 18880 +/- 3110 nM) all increased platelet cAMP to the same maximum extent, cilostamide and IBMX increased cAMP further, indicating that they inhibited a PDE isozyme in addition to PDE III.

  13. [Amanitine determination as an example of peptide analysis in the biological samples with HPLC-MS technique].

    PubMed

    Janus, Tomasz; Jasionowicz, Ewa; Potocka-Banaś, Barbara; Borowiak, Krzysztof

    Routine toxicological analysis is mostly focused on the identification of non-organic and organic, chemically different compounds, but generally with low mass, usually not greater than 500–600 Da. Peptide compounds with atomic mass higher than 900 Da are a specific analytical group. Several dozen of them are highly-toxic substances well known in toxicological practice, for example mushroom toxin and animal venoms. In the paper the authors present an example of alpha-amanitin to explain the analytical problems and different original solutions in identifying peptides in urine samples with the use of the universal LC MS/MS procedure. The analyzed material was urine samples collected from patients with potential mushroom intoxication, routinely diagnosed for amanitin determination. Ultra filtration with centrifuge filter tubes (limited mass cutoff 3 kDa) was used. Filtrate fluid was directly injected on the chromatographic column and analyzed with a mass detector (MS/MS). The separation of peptides as organic, amphoteric compounds from biological material with the use of the SPE technique is well known but requires dedicated, specific columns. The presented paper proved that with the fast and simple ultra filtration technique amanitin can be effectively isolated from urine, and the procedure offers satisfactory sensitivity of detection and eliminates the influence of the biological matrix on analytical results. Another problem which had to be solved was the non-characteristic fragmentation of peptides in the MS/MS procedure providing non-selective chromatograms. It is possible to use higher collision energies in the analytical procedure, which results in more characteristic mass spectres, although it offers lower sensitivity. The ultra filtration technique as a procedure of sample preparation is effective for the isolation of amanitin from the biological matrix. The monitoring of selected mass corresponding to transition with the loss of water molecule offers satisfactory sensitivity of determination.

  14. Social Networking Family of Caregivers during Hospitalization of Children.

    PubMed

    Menezes, Marina; Moré, Carmen Leontina Ojeda Ocampo; Barros, Luísa

    2016-06-01

    To identify and analyze the significant networks of family, social and hospital support described by the family caregivers of hospitalized children 5-12 years during the hospital stay. Descriptive study, exploratory and qualitative study conducted with 20 caregivers of children hospitalized in a hospital in a city in southern Brazil, through semi-structured interviews and significant social networks maps, tailored to the hospital setting. Data analysis showed that the most active social network was comprised of families through emotional support, material aid and services. Relations with hospital health care team and the hospital context were cited as providing support to the caregivers of the hospitalized child. The identification of social networks in the child's hospitalization course enables equip professionals working in the institution aiming at better targeting of actions and care for the family and hospitalized children. Identificar e analisar as redes significativas de suporte familiar, social e hospitalar descritas pelos familiares acompanhantes de crianças hospitalizadas de 5 a 12 anos, durante o período de internação. Estudo descritivo, exploratório e de cunho qualitativo realizado com 20 acompanhantes de crianças hospitalizadas em uma unidade hospitalar em uma cidade do Sul do Brasil, por meio de entrevistas semiestruturadas e dos Mapas de Redes sociais significativas, adaptado para o contexto hospitalar. A análise dos dados demonstrou que a rede social mais atuante foi composta por familiares, através de apoio emocional, ajuda material e de serviços. As relações com a equipe de saúde do hospital e com o contexto hospitalar foram citadas como capazes de fornecer apoio ao acompanhante da criança internada. a identificação das redes sociais no curso da hospitalização da criança possibilita instrumentalizar os profissionais que atuam na instituição objetivando um melhor direcionamento de ações e cuidados destinados à família e a criança hospitalizada.

  15. Cocrystals Strategy towards Materials for Near-Infrared Photothermal Conversion and Imaging.

    PubMed

    Wang, Yu; Zhu, Weigang; Du, Wenna; Liu, Xinfeng; Zhang, Xiaotao; Dong, Huanli; Hu, Wenping

    2018-04-03

    A cocrystal strategy with a simple preparation process is developed to prepare novel materials for near-infrared photothermal (PT) conversion and imaging. DBTTF and TCNB are selected as electron donor (D) and electron acceptor (A) to self-assemble into new cocrystals through non-covalent interactions. The strong D-A interaction leads to a narrow band gap with NIR absorption and that both the ground state and lowest-lying excited state are charge transfer states. Under the NIR laser illumination, the temperature of the cocrystal sharply increases in a short time with high PT conversion efficiency (η=18.8 %), which is due to the active non-radiative pathways and inhibition of radiative transition process, as revealed by femtosecond transient absorption spectroscopy. This is the first PT conversion cocrystal, which not only provides insights for the development of novel PT materials, but also paves the way of designing functional materials with appealing applications. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Molecular Engineering Strategy for High Efficiency Fullerene-Free Organic Solar Cells Using Conjugated 1,8-Naphthalimide and Fluorenone Building Blocks.

    PubMed

    Do, Thu Trang; Pham, Hong Duc; Manzhos, Sergei; Bell, John M; Sonar, Prashant

    2017-05-24

    We designed, synthesized, and characterized a series of novel electron deficient small molecule nonfullerene acceptors based on 1,8-naphthalimide (NAI) and 9-fluorenone (FN) with different branched alkyl chains using various techniques. These molecules are based on an acceptor-donor-acceptor-donor-acceptor (A1-D-A2-D-A1) molecular design configuration with NAI as the end-capping acceptor (A1), FN as electron-withdrawing central (A2) group, and thiophene ring as a donor (D) unit. These materials are named as NAI-FN-NAI (BO) and NAI-FN-NAI (HD) where BO and HD represent butyloctyl and hexyldecyl alkyl groups, respectively. To further modify energy levels of these materials, we converted the weak electron withdrawing ketonic group (C═O) attached to the FN moiety of NAI-FN-NAI (BO) to a stronger electron withdrawing cyano group (C≡N) to obtain the compound NAI-FCN-NAI (BO) by keeping the same alkyl chain. The optical, electrochemical, and thermal properties of the new acceptors were studied. The materials exhibited higher to medium band gaps, low lowest unoccupied molecular orbital (LUMO) energy levels, and highly thermally stable properties. Organic solar cell devices employing conventional poly(3-hexylthiophene) (P3HT) a donor polymer and the newly designed small molecules as the acceptor were investigated. Among all new materials, organic solar cell devices based on NAI-FN-NAI (BO) as an acceptor exhibit the highest performance with an open circuit voltage (V OC ) of 0.88 V, a short-circuit current density (J SC ) of 9.1 mAcm -2 , a fill factor (FF) of 45%, and an overall power conversion efficiency (PCE) of 3.6%. This is the first report of 9-fluorenone based nonfullerene acceptor with P3HT donor in organic solar cell devices with such a promising performance.

  17. Fatigue and Creep Crack Propagation behaviour of Alloy 617 in the Annealed and Aged Conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Julian K. Benz; Richard N. Wright

    2013-10-01

    The crack propagation behaviour of Alloy 617 was studied under various conditions. Elevated temperature fatigue and creep-fatigue crack growth experiments were conducted at 650 and 800 degrees C under constant stress intensity (triangle K) conditions and triangular or trapezoidal waveforms at various frequencies on as-received, aged, and carburized material. Environmental conditions included both laboratory air and characteristic VHTR impure helium. As-received Alloy 617 displayed an increase in the crack growth rate (da/dN) as the frequency was decreased in air which indicated a time-dependent contribution component in fatigue crack propagation. Material aged at 650°C did not display any influence on themore » fatigue crack growth rates nor the increasing trend of crack growth rate with decreasing frequency even though significant microstructural evolution, including y’ (Ni3Al) after short times, occurred during aging. In contrast, carburized Alloy 617 showed an increase in crack growth rates at all frequencies tested compared to the material in the standard annealed condition. Crack growth studies under quasi-constant K (i.e. creep) conditions were also completed at 650 degrees C and a stress intensity of K = 40 MPa9 (square root)m. The results indicate that crack growth is primarily intergranular and increased creep crack growth rates exist in the impure helium environment when compared to the results in laboratory air. Furthermore, the propagation rates (da/dt) continually increased for the duration of the creep crack growth either due to material aging or evolution of a crack tip creep zone. Finally, fatigue crack propagation tests at 800 degrees C on annealed Alloy 617 indicated that crack propagation rates were higher in air than impure helium at the largest frequencies and lowest stress intensities. The rates in helium, however, eventually surpass the rates in air as the frequency is reduced and the stress intensity is decreased which was not observed at 650 degrees C.« less

  18. A cosmologia no ensino da geografia

    NASA Astrophysics Data System (ADS)

    Santos, S. C.; Chiaradia, A. P. M.

    2003-08-01

    O principal objetivo deste trabalho é auxiliar o professor de Geografia em sala de aula no ensino de tópicos relacionados com a Cosmologia. A idéia deste trabalho surgiu quando foi constatado que o professor de Geografia tem dificuldades de ensinar este tópico. Esta constatação foi feita por uma das autoras ao lecionar este tópico no ensino fundamental e em discussões com outros professores de Geografia. Da mesma maneira que ocorria desde os tempos mais antigos, os alunos têm muito interesse em conhecer os fenômenos que ocorrem no Cosmo, porém os livros didáticos de Geografia utilizados em sala de aula não são ricos em informações sobre este assunto. Assim, o professor de Geografia tem poucas informações para discutir este assunto em sala de aula e não dá a devida importância para este tópico. Então, foi desenvolvido um material de apoio para professores de Geografia sobre a origem do Universo, sua evolução e seu possível futuro evolutivo segundo as mais recentes teorias, com base em perguntas feitas pelos alunos de ensino fundamental e as informações trazidas nos livros didáticos Não cabe a este material inovar e tão pouco trazer uma metodologia de ensino de Cosmologia. Neste material o professor de Geografia pode encontrará um banco de informações, que constitui no estabelecimento de conceitos, teorias e hipóteses, sobre a Cosmologia, em linguagem simples e de fácil entendimento. Para desenvolvê-lo, foram feitas pesquisas não exaustivas em livros e revistas científicas, compilação e discussão em forma cronológica das teorias aceitas sobre modelos cosmológicos. Portanto, este material será apresentado neste trabalho.

  19. Cryogenic Fracture Toughness Evaluation of an Investment Cast Al-Be Alloy for Structural Applications

    NASA Technical Reports Server (NTRS)

    Gamwell, W. R.; McGill, P. B.

    2006-01-01

    Aluminum-Beryllium metal matrix composite materials are useful due to their desirable performance characteristics for aerospace applications. Desirable characteristics of this material includes light-weight, dimensional stability, stiffness, good vibration damping characteristics, low coefficient of thermal expansion, and workability, This material is 3.5 times stiffer and 22% lighter than conventional aluminum alloys. electro-optical systems, advanced sensor and guidance components for flight and satellite systems, components for light-weight high-performance aircraft engines, and structural components for helicopters. Aluminum-beryllium materials are now available in the form of near net shape investment castings. In this materials properties characterization study, the cryogenic tensile and fracture properties of an investment casting alloy, Beralcast 363, were determined. Tensile testing was performed at 21 C (70 F), -73.3 C (-100 F), -195.5 C (-320 F) and -252.8 C (-423 F), and fracture (K(sub lc) and da/dN) testing was performed at -73.3 C (-100 F), -195.5 C (-320 F) and -252.8 C (-423 F). Their use is attractive for weight critical structural applications such as advanced

  20. Triazatruxene: A Rigid Central Donor Unit for a D-A3 Thermally Activated Delayed Fluorescence Material Exhibiting Sub-Microsecond Reverse Intersystem Crossing and Unity Quantum Yield via Multiple Singlet-Triplet State Pairs.

    PubMed

    Dos Santos, Paloma L; Ward, Jonathan S; Congrave, Daniel G; Batsanov, Andrei S; Eng, Julien; Stacey, Jessica E; Penfold, Thomas J; Monkman, Andrew P; Bryce, Martin R

    2018-06-01

    By inverting the common structural motif of thermally activated delayed fluorescence materials to a rigid donor core and multiple peripheral acceptors, reverse intersystem crossing (rISC) rates are demonstrated in an organic material that enables utilization of triplet excited states at faster rates than Ir-based phosphorescent materials. A combination of the inverted structure and multiple donor-acceptor interactions yields up to 30 vibronically coupled singlet and triplet states within 0.2 eV that are involved in rISC. This gives a significant enhancement to the rISC rate, leading to delayed fluorescence decay times as low as 103.9 ns. This new material also has an emission quantum yield ≈1 and a very small singlet-triplet gap. This work shows that it is possible to achieve both high photoluminescence quantum yield and fast rISC in the same molecule. Green organic light-emitting diode devices with external quantum efficiency >30% are demonstrated at 76 cd m -2 .

  1. Development of a material processing plant for lunar soil

    NASA Technical Reports Server (NTRS)

    Goettsch, Ulix; Ousterhout, Karl

    1992-01-01

    Currently there is considerable interest in developing in-situ materials processing plants for both the Moon and Mars. Two of the most important aspects of developing such a materials processing plant is the overall system design and the integration of the different technologies into a reliable, lightweight, and cost-effective unit. The concept of an autonomous materials processing plant that is capable of producing useful substances from lunar regolith was developed. In order for such a materials processing plant to be considered as a viable option, it must be totally self-contained, able to operate autonomously, cost effective, light weight, and fault tolerant. In order to assess the impact of different technologies on the overall systems design and integration, a one-half scale model was constructed that is capable of scooping up (or digging) lunar soil, transferring the soil to a solar furnace, heating the soil in the furnace to liberate the gasses, and transferring the spent soil to a 'tile' processing center. All aspects of the control system are handled by a 386 class PC via D/A, A/D, and DSP (Digital Signal Processor) control cards.

  2. Aspects regarding the correlation between the physical-mechanical and tribological characteristics of composites materials reinforced with carbon fibers

    NASA Astrophysics Data System (ADS)

    Caliman, R.

    2017-08-01

    The purpose of this paper is to highlight a number of factors that influence the physical-mechanical and tribological characteristics of sintered composite materials. Such factors are grouped generally in two categories: technological parameters (pressure compacting, sintering temperature, sintering duration, heat treatment) and the receipt of sintered composite materials. In this paper is presented a program of experiments developed both in composite materials sintered polymer matrix (non-metallic) and in the metal matrix (eg., Al) which was prepared in advance a methodology original production and research for this particular type of materials. The experiments have focused development and testing of a number of 14 polymer composite and 5 composite sintered Al base, in both situations armed with carbon fiber in various forms. Tribological tests followed the establishment of the coefficient of friction and wear rate of the sliding speed at the constant values (v = 7.2 mm/s) and the normal load (N = 8 daN) and for different orientations of the fibers to the direction of sliding: normal (N type), parallel (P) and antiparallel-perpendicular (AP type).

  3. Effects of education on the progression of early- versus late-stage mild cognitive impairment.

    PubMed

    Ye, Byoung Seok; Seo, Sang Won; Cho, Hanna; Kim, Seong Yoon; Lee, Jung-Sun; Kim, Eun-Joo; Lee, Yunhwan; Back, Joung Hwan; Hong, Chang Hyung; Choi, Seong Hye; Park, Kyung Won; Ku, Bon D; Moon, So Young; Kim, Sangyun; Han, Seol-Heui; Lee, Jae-Hong; Cheong, Hae-Kwan; Na, Duk L

    2013-04-01

    Highly educated participants with normal cognition show lower incidence of Alzheimer's disease (AD) than poorly educated participants, whereas longitudinal studies involving AD have reported that higher education is associated with more rapid cognitive decline. We aimed to evaluate whether highly educated amnestic mild cognitive impairment (aMCI) participants show more rapid cognitive decline than those with lower levels of education. A total of 249 aMCI patients enrolled from 31 memory clinics using the standard assessment and diagnostic processes were followed with neuropsychological evaluation (duration 17.2 ± 8.8 months). According to baseline performances on memory tests, participants were divided into early-stage aMCI (-1.5 to -1.0 standard deviation (SD)) and late-stage aMCI (below -1.5 SD) groups. Risk of AD conversion and changes in neuropsychological performances according to the level of education were evaluated. Sixty-two patients converted to AD over a mean follow-up of 1.43 years. The risk of AD conversion was higher in late-stage aMCI than early-stage aMCI. Cox proportional hazard models showed that aMCI participants, and late-stage aMCI participants in particular, with higher levels of education had a higher risk of AD conversion than those with lower levels of education. Late-stage aMCI participants with higher education showed faster cognitive decline in language, memory, and Clinical Dementia Rating Sum of Boxes (CDR-SOB) scores. On the contrary, early-stage aMCI participants with higher education showed slower cognitive decline in MMSE and CDR-SOB scores. Our findings suggest that the protective effects of education against cognitive decline remain in early-stage aMCI and disappear in late-stage aMCI.

  4. Targeting Persons With or At High Risk for Chronic Obstructive Pulmonary Disease by State-based Surveillance

    PubMed Central

    Pleasants, Roy A.; Heidari, Khosrow; Wheaton, Anne G.; Ohar, Jill A.; Strange, Charlie; Croft, Janet B.; Liao, Winston; Mannino, David M.; Kraft, Monica

    2015-01-01

    The Behavioral Risk Factor Surveillance System (BRFSS) survey is used to estimate chronic obstructive pulmonary disease (COPD) prevalence and could be expanded to describe respiratory symptoms in the general population and to characterize persons with or at high risk for the disease. Tobacco duration and respiratory symptom questions were added to the 2012 South Carolina BRFSS. Data concerning sociodemographics, chronic illnesses, health behaviors, and respiratory symptoms were collected in 9438 adults ≥ 35 years-old. Respondents were categorized as having COPD, high risk, or low risk for the disease. High risk was defined as no self-reported COPD, ≥ 10 years’ tobacco use, and ≥ 1 respiratory symptom (frequent productive cough or shortness of breath (SOB), or breathing problems affecting activities). Prevalence of self-reported and high-risk COPD were 9.1% and 8.0%, respectively. Overall, 17.3%, 10.6%, and 5.2% of all respondents reported activities limited by breathing problems, frequent productive cough, and frequent SOB, respectively. The high-risk group was more likely than the COPD group to report a productive cough and breathing problems limiting activities as well as being current smokers, male, and African-American. Health impairment was more severe in the COPD than the high-risk group, and both were worse than the low-risk group. Conclusions Persons at high risk for COPD share many, but not all, of the characteristics of persons diagnosed with the disease. Additional questions addressing smoking duration and respiratory symptoms in the BRFSS identifies groups at high risk for having or developing COPD who may benefit from smoking cessation and case-finding interventions. PMID:26367193

  5. Changes in Expression of Dopamine, Its Receptor, and Transporter in Nucleus Accumbens of Heroin-Addicted Rats with Brain-Derived Neurotrophic Factor (BDNF) Overexpression.

    PubMed

    Li, Yixin; Xia, Baijuan; Li, Rongrong; Yin, Dan; Liang, Wenmei

    2017-06-09

    BACKGROUND The aim of this study was to explore how changes in the expression of BDNF in MLDS change the effect of BDNF on dopamine (DA) neurons, which may have therapeutic implications for heroin addiction. MATERIAL AND METHODS We established a rat model of heroin addiction and observed changes in the expression of BDNF, DA, dopamine receptor (DRD), dopamine transporter (DAT), and other relevant pathways in NAc. We also assessed the effect of BDNF overexpression in the NAc, behavioral changes of heroin-conditioned place preference (CPP), and naloxone withdrawal in rats with high levels of BDNF. We established 5 adult male rat groups: heroin addiction, lentivirus transfection, blank virus, sham operation, and control. The PCR gene chip was used to study gene expression changes. BDNF lentivirus transfection was used for BDNF overexpression. A heroin CPP model and a naloxone withdrawal model of rats were established. RESULTS Expression changes were found in 20 of the 84 DA-associated genes in the NAc of heroin-addicted rats. Weight loss and withdrawal symptoms in the lentivirus group for naloxone withdrawal was less than in the blank virus and the sham operation group. These 2 latter groups also showed significant behavioral changes, but such changes were not observed in the BDNF lentivirus group before or after training. DRD3 and DAT increased in the NAc of the lentivirus group. CONCLUSIONS BDNF and DA in the NAc are involved in heroin addiction. BDNF overexpression in NAc reduces withdrawal symptoms and craving behavior for medicine induced by environmental cues for heroin-addicted rats. BDNF participates in the regulation of the dopamine system by acting on DRD3 and DAT.

  6. Optimization of Alkaline and Dilute Acid Pretreatment of Agave Bagasse by Response Surface Methodology.

    PubMed

    Ávila-Lara, Abimael I; Camberos-Flores, Jesus N; Mendoza-Pérez, Jorge A; Messina-Fernández, Sarah R; Saldaña-Duran, Claudia E; Jimenez-Ruiz, Edgar I; Sánchez-Herrera, Leticia M; Pérez-Pimienta, Jose A

    2015-01-01

    Utilization of lignocellulosic materials for the production of value-added chemicals or biofuels generally requires a pretreatment process to overcome the recalcitrance of the plant biomass for further enzymatic hydrolysis and fermentation stages. Two of the most employed pretreatment processes are the ones that used dilute acid (DA) and alkaline (AL) catalyst providing specific effects on the physicochemical structure of the biomass, such as high xylan and lignin removal for DA and AL, respectively. Another important effect that need to be studied is the use of a high solids pretreatment (≥15%) since offers many advantaged over lower solids loadings, including increased sugar and ethanol concentrations (in combination with a high solids saccharification), which will be reflected in lower capital costs; however, this data is currently limited. In this study, several variables, such as catalyst loading, retention time, and solids loading, were studied using response surface methodology (RSM) based on a factorial central composite design of DA and AL pretreatment on agave bagasse using a range of solids from 3 to 30% (w/w) to obtain optimal process conditions for each pretreatment. Subsequently enzymatic hydrolysis was performed using Novozymes Cellic CTec2 and HTec2 presented as total reducing sugar (TRS) yield. Pretreated biomass was characterized by wet-chemistry techniques and selected samples were analyzed by calorimetric techniques, and scanning electron/confocal fluorescent microscopy. RSM was also used to optimize the pretreatment conditions for maximum TRS yield. The optimum conditions were determined for AL pretreatment: 1.87% NaOH concentration, 50.3 min and 13.1% solids loading, whereas DA pretreatment: 2.1% acid concentration, 33.8 min and 8.5% solids loading.

  7. Evaluation of a newly designed sandwich enzyme linked immunosorbent assay for the detection of hydatid antigen in serum, urine and cyst fluid for diagnosis of cystic echinococcosis

    PubMed Central

    Chaya, DR; Parija, Subhash Chandra

    2013-01-01

    Introduction: Cystic echinococcosis (CE) is a zoonotic disease of humans with variable clinical manifestations. Imaging and immunological methods are currently the mainstay of diagnosis of this disease. Although the immunological tests for detection of anti-echinococcal antibodies have several disadvantages, they are widely being used. Antigen is far more superior than antibody detection test as they can provide a specific parasitic diagnosis. Materials and Methods: A sandwich enzyme linked immunosorbent assay (ELISA) was designed using antibodies to 24 kDa urinary hydatid antigen for the detection of hydatid antigens in urine, serum and cyst fluid specimens. The performance of this novel test was compared with that of other hydatid antibody detection ELISA and enzyme immune transfer blot (EITB) using radiological and surgical confirmation as the gold standard. Results: The antigen detection ELISA showed 100% sensitivity and specificity when tested with cyst fluid. On testing urine and serum, the antigen detection ELISA was found to be more specific than antibody detection ELISA. EITB was found to be the most sensitive and specific test. Conclusions: ELISA using polyclonal antibodies against 24 kDa urinary hydatid protein was moderately sensitive to detect hydatid antigen in serum and urine. Hence polyclonal antibodies to 24 kDa urinary hydatid antigen can be used as an alternative source of antibody to detect hydatid antigen in serum, urine and cyst fluid. In the present study, EITB was found to be highly specific test for detection of hydatid antibodiesin serum. 24 kDa protein was found to be specific and of diagnostic value in CE. PMID:24470996

  8. Optimization of Alkaline and Dilute Acid Pretreatment of Agave Bagasse by Response Surface Methodology

    PubMed Central

    Ávila-Lara, Abimael I.; Camberos-Flores, Jesus N.; Mendoza-Pérez, Jorge A.; Messina-Fernández, Sarah R.; Saldaña-Duran, Claudia E.; Jimenez-Ruiz, Edgar I.; Sánchez-Herrera, Leticia M.; Pérez-Pimienta, Jose A.

    2015-01-01

    Utilization of lignocellulosic materials for the production of value-added chemicals or biofuels generally requires a pretreatment process to overcome the recalcitrance of the plant biomass for further enzymatic hydrolysis and fermentation stages. Two of the most employed pretreatment processes are the ones that used dilute acid (DA) and alkaline (AL) catalyst providing specific effects on the physicochemical structure of the biomass, such as high xylan and lignin removal for DA and AL, respectively. Another important effect that need to be studied is the use of a high solids pretreatment (≥15%) since offers many advantaged over lower solids loadings, including increased sugar and ethanol concentrations (in combination with a high solids saccharification), which will be reflected in lower capital costs; however, this data is currently limited. In this study, several variables, such as catalyst loading, retention time, and solids loading, were studied using response surface methodology (RSM) based on a factorial central composite design of DA and AL pretreatment on agave bagasse using a range of solids from 3 to 30% (w/w) to obtain optimal process conditions for each pretreatment. Subsequently enzymatic hydrolysis was performed using Novozymes Cellic CTec2 and HTec2 presented as total reducing sugar (TRS) yield. Pretreated biomass was characterized by wet-chemistry techniques and selected samples were analyzed by calorimetric techniques, and scanning electron/confocal fluorescent microscopy. RSM was also used to optimize the pretreatment conditions for maximum TRS yield. The optimum conditions were determined for AL pretreatment: 1.87% NaOH concentration, 50.3 min and 13.1% solids loading, whereas DA pretreatment: 2.1% acid concentration, 33.8 min and 8.5% solids loading. PMID:26442260

  9. Dopamine, 6-hydroxydopamine, iron, and dioxygen--their mutual interactions and possible implication in the development of Parkinson's disease.

    PubMed

    Linert, W; Herlinger, E; Jameson, R F; Kienzl, E; Jellinger, K; Youdim, M B

    1996-08-23

    The reactions of dopamine (1-amino-2-(3,4-dihydroxyphenyl)-ethane, DA), 5-hydroxydopamine (5-OHDA), and 6-hydroxydopamine (6-OHDA), with molecular oxygen-with and without the addition of catalytic amounts of iron(III) and other metal ions-have been studied and the implication of these results with respect to the chemistry involved in the progress of Parkinson's disease is discussed. In the presence of O2 DA reacts spontaneously without the necessity of metal-ion catalysis under the production of stoichiometric amounts of H2O2, to form initially pink dopaminochrome, which is not stable and reacts further (without the consumption of dioxygen) to form the insoluble polymeric material known as 'melanine'. DA reacts with iron(III) yielding an intermediate 1:1 complex, which decomposes releasing Fe(II) and the semiquinone, which reacts further under involvement of both Fe(III) and dioxygen. 6-OHDA reacts without showing the necessity of such an intermediate, and it is shown to be able to release iron as Fe(II) from ferritine. On the other hand, it is shown (in vitro) that Fe(II) reacts in a Fenton type reaction with DA and the present H2O2 producing 5-OHDA and especially 6-OHDA. Based on these mutual interacting reactions a mechanism for the initiation and progress of Parkinson's disease is suggested. The catalytic effects of some other transition-metal ions are presented and an explanation for the peculiarly toxic effects of manganese(II) is put forward. Finally, a possible reason for the effect that nicotine has in the mitigation of Parkinson's disease is discussed.

  10. Fluorescence fingerprints and Cu2+-complexing ability of individual molecular size fractions in soil- and waste-borne DOM.

    PubMed

    Knoth de Zarruk, K; Scholer, G; Dudal, Y

    2007-09-01

    Land spreading of organic materials introduces large amounts of dissolved organic matter (DOM) into the soil. DOM has the ability to form stable complexes with heavy metals and can facilitate their transport towards the groundwater. The effects on soil processes are difficult to assess, because different DOM components might react differently towards metal ions. The objective of this study was to investigate the fluorescence signature and the Cu2+-binding capacity of individual molecular size fractions of DOM from various sources. DOM extracted from leaf compost, chicken manure, sugar cane vinasse and a fulvic hypercalcaric cambisol was fractionated by the means of dialysis into four molecular size classes: MW<500, 50012000-14000 Da. Vinasse and leaf compost contained around 80% and 70%, respectively, of the total organic carbon in the fractions with low molecular weight (MW<3500 Da); in chicken manure and soil these fractions accounted for 40% and 50% only. Fluorescence was highest in the fraction MW>12000 Da for leaf compost, chicken manure and soil. The opposite result was obtained for vinasse, where the fractions with low molecular weight showed highest fluorescence intensities, distinguishing it from all other samples. Vinasse showed the greatest ability to bind Cu2+ with a resulting complex concentration of 6.31mgl(-1) while in contact with an excess of Cu2+. Leaf compost, soil and chicken manure followed with 2.69, 1.12, and 0.85mgl(-1), respectively. Within vinasse, the fraction MW<500 Da was able to form the most DOM-Cu complexes, indicating the importance of low molecular weight fractions in metal binding.

  11. Effectiveness of a nursing intervention in decreasing the anxiety levels of family members of patients undergoing cardiac surgery: a randomized clinical trial.

    PubMed

    Hamester, Letícia; Souza, Emiliane Nogueira de; Cielo, Cibele; Moraes, Maria Antonieta; Pellanda, Lúcia Campos

    2016-08-15

    to verify the effectiveness of nursing orientation provided to families of patients in the immediate post-operative following cardiac surgery before the first visit to the post-anesthesia care unit, in decreasing anxiety levels, compared to the unit's routine orientation. open randomized clinical trial addressing family members in the waiting room before the first visit in the immediate post-operative period. The family members assigned to the intervention group received audiovisual orientation concerning the patients' conditions at the time and the control group received the unit's routine orientation. Outcome anxiety was assessed using the STAI-State. 210 individuals were included, 105 in each group, aged 46.4 years old on average (±14.5); 69% were female and 41% were the patients' children. The mean score obtained on the anxiety assessment in the intervention group was 41.3±8.6, while the control group scored 50.6±9.4 (p<0.001). a nursing intervention focused on providing guidance to families before their first visit to patients in the immediate post-operative period of cardiac surgery helps to decrease the levels of anxiety of companions, making them feel better prepared for the moment. ReBEC (Brazilian Clinical Trials Registry) and The Universal Trial Number (UTN), No. U1111-1145-6172. verificar a efetividade das orientações de enfermagem a familiares de pacientes em pós-operatório imediato de cirurgia cardíaca, antes da primeira visita na sala de recuperação pós-anestésica, nos níveis de ansiedade, comparados com a orientação de rotina da unidade. ensaio clínico randomizado, realizado com familiares abordados na sala de espera, antes da primeira visita no pós-operatório imediato. Familiares alocados no grupo intervenção receberam orientações audiovisuais sobre as condições em que o paciente se encontrava naquele momento, e o grupo controle recebeu as orientações de rotina da unidade. O desfecho ansiedade foi avaliado pelo inventário IDATE. foram incluídos 210 sujeitos, 105 em cada grupo, com idade média de 46,4±14,5 anos, sendo 69% do sexo feminino e 41% filhos dos pacientes. Na avaliação da ansiedade, o escore médio para o grupo intervenção foi de 41,3±8,6 pontos e, para o grupo controle, 50,6±9,4 pontos (p<0,001). a intervenção de enfermagem voltada à orientação de familiares, no momento que antecede a primeira visita no pós-operatório imediato de cirurgia cardíaca, contribui para possível redução da ansiedade dos acompanhantes, contribuindo para que se sintam mais preparados para esse momento. Registro Brasileiro de Ensaios Clínicos (ReBEC) e The Universal Trial Number (UTN), sob o número U1111-1145-6172. verificar la efectividad de las orientaciones de enfermería - dadas a familiares de pacientes en el posoperatorio inmediato de cirugía cardíaca, antes de la primera visita, en la sala de recuperación postanestésica - en los niveles de ansiedad, comparados con la orientación de rutina de la unidad. ensayo clínico aleatorio, realizado con familiares abordados en la sala de espera, antes de la primera visita en el posoperatorio inmediato. Familiares designados para el grupo intervención recibieron orientaciones audiovisuales sobre las condiciones en que el paciente se encontraba en aquel momento, y el grupo control recibió las orientaciones de rutina de la unidad. El resultado ansiedad fue evaluado por el inventario IDATE. fueron incluidos 210 sujetos, 105 en cada grupo, con edad promedio de 46,4±14,5 años, siendo 69% del sexo femenino y 41% eran hijos de los pacientes. En la evaluación de la ansiedad, el puntaje promedio para el grupo intervención fue de 41,3±8,6 puntos y, para el grupo control, 50,6±9,4 puntos (p<0,001). la intervención de enfermería dirigida a orientar a familiares, en el momento que antecede a la primera visita en el posoperatorio inmediato de cirugía cardíaca, induce una posible reducción de la ansiedad de los acompañantes, contribuyendo para que se sientan más preparados para ese momento. Registro Brasileño de Ensayos Clínicos (ReBEC) y The Universal Trial Number (UTN), bajo el no U1111-1145-6172.

  12. Numerical Simulation of Detonation in Condensed Phase Explosives

    DTIC Science & Technology

    1998-08-01

    34Numerical modelling of shocks in solids with elastic-plastic conditions", Shock Waves, 3: 55-66. 22. Jones, D.A., Oran, E.S. and Guirguis , R. (1990). "A...China Lake, CA 93555-6001, preprint. 55. P.J. Miller , P.J. and G.T. Sutherland, G.T. (1996) Reaction Rate Modelling of PBXN- 110, Shock Compression...report describes the development of a two-dimensional multi-material Eulerian hydrocode to model the effects of detonating condensed phase explosives on

  13. The Effect of Defects on the Fatigue Initiation Process in Two P/M Superalloys.

    DTIC Science & Technology

    1980-09-01

    determine the effect of Sdfect size, shape, and population on the fatigue initiation process in two high strength P/M superalloys, AF-l5 and AF2-lDA. The...to systematically determine the effects of defect size, shape, and population on fatigue. It is true that certain trends have been established...to determine the relative effects of defect size, shape, and population on the crack initiation life of a representative engineering material

  14. Information Management: Publishing and Printing: Army Publishing: Action Officers Guide

    DTIC Science & Technology

    2002-04-30

    types of lists: ordered (such as numerical, alphabetical, or sequential ), bulleted, or dashed. (4) Extracted material in an appendix must be identified...provide supporting, expanded, or sequential doctrinal manuals within a functional field (this number group must not exceed 3 digits). Table 13–2...rubup, opaquing, lineup , and register, and so forth 1,2 190 DA PAM 25–40 • 30 April 2002 Table J–5 Camera, platemaking, and related equipment—Continued

  15. Organization of the Optical Society of America Photonic Science Topical Meeting Series. Volume 3. The Microphysics of Surfaces: Beam-Induced Processes Held in Santa Fe, New Mexico on 11-13 February 1991

    DTIC Science & Technology

    1992-05-22

    as semiconductor material. Impor- tant applications are thin film solar cells, thin film transistors for liquid crystal displays, photoreceptors for...171, 1989. 307-311 3 T.MINAMI, H.NANTO and S.TAKATA, Thin Solid Films, Vol.124, 1985. 43-47 4 D.Z.DA, F.R.ZHU and H.S.TANG, Acta Energiae Solaris

  16. No Evidence for Multiple Stellar Populations in the Low-mass Galactic Globular Cluster E 3

    NASA Astrophysics Data System (ADS)

    Salinas, Ricardo; Strader, Jay

    2015-08-01

    Multiple stellar populations are a widespread phenomenon among Galactic globular clusters. Even though the origin of the enriched material from which new generations of stars are produced remains unclear, it is likely that self-enrichment will be feasible only in clusters massive enough to retain this enriched material. We searched for multiple populations in the low mass (M˜ 1.4× {10}4 {M}⊙ ) globular cluster E3, analyzing SOAR/Goodman multi-object spectroscopy centered on the blue cyanogen (CN) absorption features of 23 red giant branch stars. We find that the CN abundance does not present the typical bimodal behavior seen in clusters hosting multistellar populations, but rather a unimodal distribution that indicates the presence of a genuine single stellar population, or a level of enrichment much lower than in clusters that show evidence for two populations from high-resolution spectroscopy. E3 would be the first bona fide Galactic old globular cluster where no sign of self-enrichment is found. Based on observations obtained at the Southern Astrophysical Research (SOAR) Telescope, which is a joint project of the Ministério da Ciência, Tecnologia, e Inovação (MCTI) da República Federativa do Brasil, the US National Optical Astronomy Observatory (NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU).

  17. Facile synthesis of p-type Zn-doped α-Fe2O3 films for solar water splitting

    NASA Astrophysics Data System (ADS)

    Kuo, Chun-Lin; Hsu, Yu-Kuei; Lin, Yan-Gu

    2014-10-01

    A facile and simple fabrication of Zn-doped α-Fe2O3 thin films as a photocathode for solar hydrogen generation was proposed in this report. Transparent Zn-doped α-Fe2O3 films were prepared by a deposition-annealing (DA) process using nontoxic iron(III) chloride as the Fe precursor and zinc chloride as a acceptor dopant, followed by annealing at 550 °C in air. In terms of the structural examination of as-grown samples, X-ray diffraction analysis demonstrated an increase in the lattice parameters of Zn incorporated in Fe2O3 by substituting Fe in the host lattice. No second phase was determined, indicating no phase separation in the ternary materials. Energy dispersive spectroscopy results demonstrated that Zn, Fe, and O elements existed in the deposits. Furthermore, impedance measurements show that the Zn-dopant serves as an hole acceptor and increases the acceptor concentration by increasing concentration of zinc precursor. Significantly, the photoelectrochemical measurements exhibited remarkable cathodic current, corresponding to the reduction reaction of hydrogen. Finally, the optimum photocurrent can be achieved by controlled variation of the Fe and Zni precursor concentration, annealing conditions, and the number of DA cycles. According to our investigation, the understandings of morphology effect on PEC activity give the blueprint for materials design in the application of solar hydrogen.

  18. Amid the possible causes of a very famous foxing: molecular and microscopic insight into Leonardo da Vinci's self-portrait.

    PubMed

    Piñar, Guadalupe; Tafer, Hakim; Sterflinger, Katja; Pinzari, Flavia

    2015-12-01

    Leonardo da Vinci's self-portrait is affected by foxing spots. The portrait has no fungal or bacterial infections in place, but is contaminated with airborne spores and fungal material that could play a role in its disfigurement. The knowledge of the nature of the stains is of great concern because future conservation treatments should be derived from scientific investigations. The lack of reliable scientific data, due to the non-culturability of the microorganisms inhabiting the portrait, prompted the investigation of the drawing using non-invasive and micro-invasive sampling, in combination with scanning electron microscope (SEM) imaging and molecular techniques. The fungus Eurotium halophilicum was found in foxing spots using SEM analyses. Oxalates of fungal origin were also documented. Both findings are consistent with the hypothesis that tonophilic fungi germinate on paper metabolizing organic acids, oligosaccharides and proteic compounds, which react chemically with the material at a low water activity, forming brown products and oxidative reactions resulting in foxing spots. Additionally, molecular techniques enabled a screening of the fungi inhabiting the portrait and showed differences when different sampling techniques were employed. Swabs samples showed a high abundance of lichenized Ascomycota, while the membrane filters showed a dominance of Acremonium sp. colonizing the drawing. © 2015 The Authors. Environmental Microbiology Reports published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  19. Interdisciplinary paleovegetation study in the Fernando de Noronha Island (Pernambuco State), northeastern Brazil.

    PubMed

    Pessenda, Luiz C R; Gouveia, Susy E M; Ledru, Marie-Pierre; Aravena, Ramon; Ricardi-Branco, Fresia S; Bendassolli, José A; Ribeiro, Adauto de S; Saia, Soraya E M G; Sifeddine, Abdelfettah; Menor, Eldemar de A; Oliveira, Sônia M B de; Cordeiro, Renato C; Freitas, Angela M de M; Boulet, René; Filizola, Heloisa F

    2008-12-01

    The aim of this research was to reconstruct vegetation changes (with climate inferences) that occurred during the Holocene in the Fernando de Noronha Island, Pernambuco State, northeastern Brazil. The research approach included the use of geochemical (mineralogy, elemental), carbon isotopes (delta13C, 14C) and pollen analyses in soil organic matter (SOM) and sediments collected in Lagoa da Viração and Manguezal do Sueste. The carbon isotopes data of SOM indicated that there was no significant vegetation changes during the last 7400 BP, suggesting that the climate was not the determinant factor for the vegetation dynamics. The pollen analysis of the sediment of a core collected in the Lagoa da Viração showed the absence of Quaternary material in the period between 720 BP and 90 BP. The mineralogical analysis of deeper layer showed the presence of diopside indicating this material was developed "in situ". Only in the shallow part of the core were found pollen of similar plant species of the modern vegetation. The geochemistry and isotope results, in association with the sediment type and pollen analyses of sediment samples of Manguezal do Sueste, indicated variations in the vegetation and in its location since the middle Holocene. Such variations can be associated with climatic events and sea level oscillations and also with anthropogenic events considering the last five hundred years.

  20. Soft Robotic Manipulator for Improving Dexterity in Minimally Invasive Surgery.

    PubMed

    Diodato, Alessandro; Brancadoro, Margherita; De Rossi, Giacomo; Abidi, Haider; Dall'Alba, Diego; Muradore, Riccardo; Ciuti, Gastone; Fiorini, Paolo; Menciassi, Arianna; Cianchetti, Matteo

    2018-02-01

    Combining the strengths of surgical robotics and minimally invasive surgery (MIS) holds the potential to revolutionize surgical interventions. The MIS advantages for the patients are obvious, but the use of instrumentation suitable for MIS often translates in limiting the surgeon capabilities (eg, reduction of dexterity and maneuverability and demanding navigation around organs). To overcome these shortcomings, the application of soft robotics technologies and approaches can be beneficial. The use of devices based on soft materials is already demonstrating several advantages in all the exploitation areas where dexterity and safe interaction are needed. In this article, the authors demonstrate that soft robotics can be synergistically used with traditional rigid tools to improve the robotic system capabilities and without affecting the usability of the robotic platform. A bioinspired soft manipulator equipped with a miniaturized camera has been integrated with the Endoscopic Camera Manipulator arm of the da Vinci Research Kit both from hardware and software viewpoints. Usability of the integrated system has been evaluated with nonexpert users through a standard protocol to highlight difficulties in controlling the soft manipulator. This is the first time that an endoscopic tool based on soft materials has been integrated into a surgical robot. The soft endoscopic camera can be easily operated through the da Vinci Research Kit master console, thus increasing the workspace and the dexterity, and without limiting intuitive and friendly use.

  1. Abundância química de simbióticas na direção do bojo galáctico

    NASA Astrophysics Data System (ADS)

    Luna, G. J. M.; Costa, R. D. D.

    2003-08-01

    O estudo da distribuição de metalicidades de gigantes K no Bojo indica um largo intervalo com valores entre 0.1 a 10 vezes o valor solar. As razões elementais Ca/Fe, Si/Fe, Mg/Fe são típicas de estrelas do halo, apontando para um processo rápido de enriquecimento, via estrelas masssivas (SN's tipo II). No entanto, este cenário não combina com os resultados derivados de nebulosas planetárias do bojo tais como os de Ratag et al. (1992, A&A,255,270), Cuisinier et al.(2000, A&A,353, 543), Escudero e Costa (2001, A&A,380, 300),que obtêm abundâncias análogas às do disco. Neste cenário, o estudo de estrelas simbióticas possibilita uma abordagem particularmente apropriada para o problema das abundâncias químicas de estrelas de massa intermediária em estágios avançados da evoluçao estelar. Apresentamos aqui os resultados da determinacão das abundâncias do grupo do CNO numa extensa amostra de simbióticas do bojo. Aliás, com a disponibilidade de espectros no visível determinamos também abundâncias de Ar, Ne, S e He, fundamentais para analisar os processos de enriquecimento químico ocorridos ao longo da evolução estelar, bem como a evolução química do meio interestelar. Com os espectros UV do satelite IUE obtivemos abundâncias de C, necessárias no estudo da evolução dos sistemas. As relaçoes C/N-O/N mostram que o material nebular é produto do vento da componente gigante e não dos eventos de nova que às vezes acontecem nestes sistemas, como foi mostrado por Nussbaumer et al (1988,A&A,198,179). As abundâncias de Ar, S, Ne e O são compativeis com resultados de fontes no disco e bojo, seguindo o gradiente proposto por muitos autores na literatura a partir de diferentes objetos como cefeidas, nebulosas planetárias e anãs G. (CAPES,FAPESP,CNPq)

  2. Recent advances in polymer supporting layered double hydroxides nanocomposite for electrochemical biosensors

    NASA Astrophysics Data System (ADS)

    Dhanasekaran, T.; Padmanaban, A.; Gnanamoorthy, G.; Manigandan, R.; Praveen Kumar, S.; Stephen, A.; Narayanan, V.

    2018-01-01

    In recent years, layered double hydroxides (LDHs) materials having emerging due to their ability of intercalate a variety of anions, either organic or inorganic molecules. The most significance of the LDHs has been found potential applications in catalysis, wastewater treatment, and electrochemical sensors. The Mg-Al LDHs (MAL) and Poly-o-phenylenediamine @ Mg-Al LDHs (P-MAL) was prepared via simple one step hydrothermal method. As prepared material was characterized using many techniques such as, the structural and crystal phase was determined from XRD and Raman analyses. The functional groups were depicted using FT-IR spectroscopy. The optical propertied studied using diffuse reflectance spectroscopy UV-vis spectroscopy and the emission property were analyzed from Photoluminescence spectroscopy. The surface morphology and average particle size was analyzed using FESEM microscopy. The prepared polymer composite material P-MAL was further used for highly sensitive electrochemical detection towards dopamine (DA).

  3. Bioactive Hydrogels Made from Step-Growth Derived PEG-Peptide Macromers

    PubMed Central

    Miller, Jordan S.; Shen, Colette J.; Legant, Wesley R.; Baranski, Jan D.; Blakely, Brandon L.; Chen, Christopher S.

    2010-01-01

    Synthetic hydrogels based on poly(ethylene glycol) (PEG) have been used as biomaterials for cell biology and tissue engineering investigations. Bioactive PEG-based gels have largely relied on heterobifunctional or multi-arm PEG precursors that can be difficult to synthesize and characterize or expensive to obtain. Here, we report an alternative strategy, which instead uses inexpensive and readily available PEG precursors to simplify reactant sourcing. This new approach provides a robust system in which to probe cellular interactions with the microenvironment. We used the step-growth polymerization of PEG diacrylate (PEGDA, 3400 Da) with bis-cysteine matrix metalloproteinase (MMP)-sensitive peptides via Michael-type addition to form biodegradable photoactive macromers of the form acrylate-PEG-(peptide-PEG)m-acrylate. The molecular weight (MW) of these macromers is controlled by the stoichiometry of the reaction, with a high proportion of resultant macromer species greater than 500 kDa. In addition, the polydispersity of these materials was nearly identical for three different MMP-sensitive peptide sequences subjected to the same reaction conditions. When photopolymerized into hydrogels, these high MW materials exhibit increased swelling and sensitivity to collagenase-mediated degradation as compared to previously published PEG hydrogel systems. Cell-adhesive acrylate-PEG-CGRGDS was synthesized similarly and its immobilization and stability in solid hydrogels was characterized with a modified Lowry assay. To illustrate the functional utility of this approach in a biological setting, we applied this system to develop materials that promote angiogenesis in an ex vivo aortic arch explant assay. We demonstrate the formation and invasion of new sprouts mediated by endothelial cells into the hydrogels from embedded embryonic chick aortic arches. Furthermore, we show that this capillary sprouting and three-dimensional migration of endothelial cells can be tuned by engineering the MMP-susceptibility of the hydrogels and the presence of functional immobilized adhesive ligands (CGRGDS vs. CGRGES peptide). The facile chemistry described and significant cellular responses observed suggest the usefulness of these materials in a variety of in vitro and ex vivo biologic investigations, and may aid in the design or refinement of material systems for a range of tissue engineering approaches. PMID:20138664

  4. Altered enzymatic activity and allele frequency of OMI/HTRA2 in Alzheimer's disease

    PubMed Central

    Westerlund, Marie; Behbahani, Homira; Gellhaar, Sandra; Forsell, Charlotte; Belin, Andrea Carmine; Anvret, Anna; Zettergren, Anna; Nissbrandt, Hans; Lind, Charlotta; Sydow, Olof; Graff, Caroline; Olson, Lars; Ankarcrona, Maria; Galter, Dagmar

    2011-01-01

    The serine-protease OMI/HTRA2, required for several cellular processes, including mitochondrial function, autophagy, chaperone activity, and apoptosis, has been implicated in the pathogenesis of both Alzheimer's disease (AD) and Parkinson's disease (PD). Western blot quantification of OMI/HTRA2 in frontal cortex of patients with AD (n=10) and control subjects (n=10) in two separate materials indicated reduced processed (active, 35 kDa) OMI/HTRA2 levels, whereas unprocessed (50 kDa) enzyme levels were not significantly different between the groups. Interestingly, the specific protease activity of OMI/HTRA2 was found to be significantly increased in patients with AD (n=10) compared to matched control subjects (n=10) in frontal cortex in two separate materials. Comparison of OMI/HTRA2 mRNA levels in frontal cortex and hippocampus, two brain areas particularly affected by AD, indicated similar levels in patients with AD (n=10) and matched control subjects (n=10). In addition, we analyzed the occurrence of the OMI/HTRA2 variants A141S and G399S in Swedish case-control materials for AD and PD and found a weak association of A141S with AD, but not with PD. In conclusion, our genetic, histological, and biochemical findings give further support to an involvement of OMI/HTRA2 in the pathology of AD; however, further studies are needed to clarify the role of this gene in neurodegeneration.—Westerlund, M., Behbahani, H., Gellhaar, S., Forsell, C., Carmine Belin, A., Anvret, A., Zettergren, A., Nissbrandt, H., Lind, C., Sydow, O., Graff, C., Olson, L., Ankarcrona, M., Galter, D. Altered enzymatic activity and allele frequency of OMI/HTRA2 in Alzheimer's disease. PMID:21163861

  5. 76 FR 12627 - Airworthiness Directives; Diamond Aircraft Industries GmbH Models DA 42, DA 42 NG, and DA 42 M-NG...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-08

    ... Industries GmbH Models DA 42, DA 42 NG, and DA 42 M-NG Airplanes AGENCY: Federal Aviation Administration (FAA... on Diamond aeroplanes, the majority of which were DA 40. In additional, at least 18 doors have been... conditions) while the aeroplane was parked. All DA 40 and DA 42 aeroplanes have a system installed that...

  6. Wear Calculation for Sliding Friction Pairs

    NASA Astrophysics Data System (ADS)

    Springis, G.; Rudzitis, J.; Avisane, A.; Leitans, A.

    2014-04-01

    One of the principal objectives of modern production process is the improvement of quality level; this means also guaranteeing the required service life of different products and increase in their wear resistance. To perform this task, prediction of service life of fitted components is of crucial value, since with the development of production technologies and measuring devices it is possible to determine with ever increasing precision the data to be used also in analytical calculations. Having studied the prediction theories of wear process that have been developed in the course of time and can be classified into definite groups one can state that each of them has shortcomings that might strongly impair the results thus making unnecessary theoretical calculations. The proposed model for wear calculation is based on the application of theories from several branches of science to the description of 3D surface micro-topography, assessing the material's physical and mechanical characteristics, substantiating the regularities in creation of the material particles separated during the wear process and taking into consideration definite service conditions of fittings. ums Mūsdienu ražošanas procesa viens no pamatmērķiem ir produkcijas kvalitātes līmeņa paaugstināšana, tas nozīmē arī dažādu izstrādājumu nepieciešamā kalpošanas laika nodrošināšanu un nodilumizturības palielināšanu. Svarīga loma šī uzdevuma sasniegšanā ir salāgojamo detaļu kalpošanas laika prognozēšanai, kas ir ļoti aktuāls jautājums, jo attīstoties dažādām ražošanas, kā arī mēriekārtu tehnoloģijām, kļūst iespējams arvien precīzāk noteikt nepieciešamos datus, kuri vēlāk tiek izmantoti arī analītiskajos aprēķinos. Apskatot laika gaitā izstrādātās dilšanas procesa prognozēšanas teorijas, kuras var klasificēt, apkopojot tās noteiktās grupās, ņemot par pamatu līdzīgas teorētiskās pieejas, jāsaka, ka katrai no tām piemīt dažādi trūkumi, kuri var ietekmēt rezultātu precizitāti, neievērtējot svarīgus pamatparametrus, kā arī radīt nepieciešamību pēc nelietderīgiem papildus praktiskajiem eksperimentiem, kā rezultātā zūd nepieciešamība pēc teorētiskā aprēķina. Piedāvātais dilšanas procesa aprēķinu modelis ir balstīts uz vairāku zinātnes nozaru teoriju pielietošanu, piemērojot šīs teorijas 3D virsmas mikrotopogrāfijas aprakstā, ievērtējot materiāla fizikāli-mehāniskos raksturlielumus, pamatojot dilšanas procesā radušos atdalīto materiāla daļiņu rašanās likumsakarības un ņemot vērā konkrētus salāgojuma ekspluatācijas apstākļus.

  7. Molecular modeling and cytotoxicity of diffractaic acid: HP-β-CD inclusion complex encapsulated in microspheres.

    PubMed

    Silva, Camilla V N S; Barbosa, Jéssica A P; Ferraz, Milena S; Silva, Nicácio H; Honda, Neli K; Rabello, Marcelo M; Hernandes, Marcelo Z; Bezerra, Beatriz P; Cavalcanti, Isabella M F; Ayala, Alejandro P; Santos, Noemia P S; Santos-Magalhães, Nereide S

    2016-11-01

    In this pioneer study, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) was used to improve the solubility of the diffractaic acid (DA) via inclusion complex (DA:HP-β-CD). Subsequently, DA:HP-β-CD was incorporated into poly-ε-caprolactone (PCL) microspheres (DA:HP-β-CD-MS). Microspheres containing DA (DA-MS) or DA:HP-β-CD (DA:HP-β-CD-MS) were prepared using the multiple W/O/W emulsion-solvent evaporation technique. The phase-solubility diagram of DA in HP-β-CD (10-50mM) showed an A L type curve with a stability constant K 1:1 =821M -1 . 1 H NMR, FTIR, X-ray diffraction and thermal analysis showed changes in the molecular environment of DA in DA:HP-β-CD. The molecular modeling approach suggests a guest-host complex formation between the carboxylic moiety of both DA and the host (HP-β-CD). The mean particle size of the microspheres were ∅ DA-MS =5.23±1.65μm and ∅ DA:HP-β-CD-MS =4.11±1.39μm, respectively. The zeta potential values of the microspheres were ζ DA-MS =-7.85±0.32mV and ζ DA:HP-β-CD-MS =-6.93±0.46mV. Moreover, the encapsulation of DA:HP-β-CD into microspheres resulted in a more slower release (k 2 =0.042±0.001; r 2 =0.996) when compared with DA-MS (k 2 =0.183±0.005; r 2 =0.996). The encapsulation of DA or DA:HP-β-CD into microspheres reduced the cytotoxicity of DA (IC 50 =43.29μM) against Vero cells (IC 50 of DA-MS=108.48μM and IC 50 of DA:HP-β-CD-MS=142.63μM). Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Methamphetamine-induced neurotoxicity disrupts pharmacologically evoked dopamine transients in the dorsomedial and dorsolateral striatum.

    PubMed

    Robinson, John D; Howard, Christopher D; Pastuzyn, Elissa D; Byers, Diane L; Keefe, Kristen A; Garris, Paul A

    2014-08-01

    Phasic dopamine (DA) signaling, during which burst firing by DA neurons generates short-lived elevations in extracellular DA in terminal fields called DA transients, is implicated in reinforcement learning. Disrupted phasic DA signaling is proposed to link DA depletions and cognitive-behavioral impairment in methamphetamine (METH)-induced neurotoxicity. Here, we further investigated this disruption by assessing effects of METH pretreatment on DA transients elicited by a drug cocktail of raclopride, a D2 DA receptor antagonist, and nomifensine, an inhibitor of the dopamine transporter (DAT). One advantage of this approach is that pharmacological activation provides a large, high-quality data set of transients elicited by endogenous burst firing of DA neurons for analysis of regional differences and neurotoxicity. These pharmacologically evoked DA transients were measured in the dorsomedial (DM) and dorsolateral (DL) striatum of urethane-anesthetized rats by fast-scan cyclic voltammetry. Electrically evoked DA levels were also recorded to quantify DA release and uptake, and DAT binding was determined by means of autoradiography to index DA denervation. Pharmacologically evoked DA transients in intact animals exhibited a greater amplitude and frequency and shorter duration in the DM compared to the DL striatum, despite similar pre- and post-drug assessments of DA release and uptake in both sub-regions as determined from the electrically evoked DA signals. METH pretreatment reduced transient activity. The most prominent effect of METH pretreatment on transients across striatal sub-region was decreased amplitude, which mirrored decreased DAT binding and was accompanied by decreased DA release. Overall, these results identify marked intrastriatal differences in the activity of DA transients that appear independent of presynaptic mechanisms for DA release and uptake and further support disrupted phasic DA signaling mediated by decreased DA release in rats with METH-induced neurotoxicity.

  9. Microbiological characterization of Serra da Estrela cheese throughout its Appellation d'Origine Protégée region.

    PubMed

    Tavaria, F K; Malcata, F X

    1998-05-01

    The purpose of this study was to assess the typical microbiological quality of the most famous Portuguese traditional cheese, Serra da Estrela, and to assess its ripening time and geographical dependence. Ninety-six experimental cheeses manufactured from sixteen batches of milk on eight dairy farms scattered over the Appellation d' Origine Protégée (AOP) region were qualitatively and quantitatively evaluated microbiologically at various ripening times. Viable counts were performed after inoculation on appropriate selective media for aerobic mesophiles and proteolytic and lipolytic microflora, as well as lactococci, lactobacilli, species of Enterobacteriaceae, lactic streptococci, staphylococci, and yeasts. Members of the Enterobacteriaceae and lactic acid bacteria were the predominant microbial groups on all dairy farms throughout maturation; the latter are probably the microbial group responsible for most proteolytic and lipolytic breakdown in Serra da Estrela cheese. The microbial groups whose numbers were most affected by dairy-to-dairy variation were species of Enterobacteriaceae staphylococci, and enterococci, which are the most critical groups in terms of health hazards. It is therefore suggested that tighter control should be implemented at the level of choice of raw materials, in milk-handling practices, and in general throughout the manufacturing process in attempts to standardize production and consistently reduce microbiological risks (even though the distinctiveness of a few final organoleptic characteristics may somehow be reduced.

  10. Striatal dopamine neurotransmission: regulation of release and uptake

    PubMed Central

    Sulzer, David; Cragg, Stephanie J.; Rice, Margaret E.

    2016-01-01

    Dopamine (DA) transmission is governed by processes that regulate release from axonal boutons in the forebrain and the somatodendritic compartment in midbrain, and by clearance by the DA transporter, diffusion, and extracellular metabolism. We review how axonal DA release is regulated by neuronal activity and by autoreceptors and heteroreceptors, and address how quantal release events are regulated in size and frequency. In brain regions densely innervated by DA axons, DA clearance is due predominantly to uptake by the DA transporter, whereas in cortex, midbrain, and other regions with relatively sparse DA inputs, the norepinephrine transporter and diffusion are involved. We discuss the role of DA uptake in restricting the sphere of influence of DA and in temporal accumulation of extracellular DA levels upon successive action potentials. The tonic discharge activity of DA neurons may be translated into a tonic extracellular DA level, whereas their bursting activity can generate discrete extracellular DA transients. PMID:27141430

  11. Polyethyleneimine Capped Silver Nanoclusters as Efficient Antibacterial Agents.

    PubMed

    Xu, Dong; Wang, Qingyun; Yang, Tao; Cao, Jianzhong; Lin, Qinlu; Yuan, Zhiqin; Li, Le

    2016-03-18

    Development of efficient antibacterial agents is critical for human health. In the present study, we investigated the antibacterial activity of polyethyleneimine (PEI)-capped silver nanoclusters (PEI-AgNCs), based on the fact that nanoclusters normally have higher surface-to-volume ratios than traditional nanomaterials and PEI itself has a strong antimicrobial capacity. We synthesized stable silver nanoclusters by altering PEI molecular weight from 0.6 kDa to 25 kDa and characterized them by UV-Vis absorption and fluorescence spectroscopy and high resolution transmission electron microscopy. The sizes of AgNCs were around 2 nm in diameter and were little influenced by the molecular weight of PEIs. The antibacterial abilities of the four PEI-AgNCs were explored on agar plate and in liquid systems. Our results revealed that the antibacterial activity of PEI-AgNCs is excellent and the reduction of PEI molecular weight could result in the increased antibacterial capacity of PEI-AgNCs. Such proposed new materials might be useful as efficient antibacterial agents in practical clinical applications.

  12. Simultaneous/Selective Detection of Dopamine and Ascorbic Acid at Synthetic Zeolite-Modified/Graphite-Epoxy Composite Macro/Quasi-Microelectrodes

    PubMed Central

    Ilinoiu, Elida Cristina; Manea, Florica; Serra, Pier Andrea; Pode, Rodica

    2013-01-01

    The present paper aims to miniaturize a graphite-epoxy and synthetic zeolite-modified graphite-epoxy composite macroelectrode as a quasi-microelectrode aiming in vitro and also, envisaging in vivo simultaneous electrochemical detection of dopamine (DA) and ascorbic acid (AA) neurotransmitters, or DA detection in the presence of AA. The electrochemical behavior and the response of the designed materials to the presence of dopamine and ascorbic acid without any protective membranes were studied by cyclic voltammetry and constant-potential amperometry techniques. The catalytic effect towards dopamine detection was proved for the synthetic zeolite-modified graphite-epoxy composite quasi-microelectrode, allowing increasing the sensitivity and selectivity for this analyte detection, besides a possible electrostatic attraction between dopamine cation and the negative surface of the synthetic zeolite and electrostatic repulsion with ascorbic acid anion. Also, the synthetic zeolite-modified graphite-epoxy composite quasi-microelectrode gave the best electroanalytical parameters for dopamine detection using constant-potential amperometry, the most useful technique for practical applications. PMID:23736851

  13. Two new β-glucosidases from ethanol-fermenting fungus Mucor circinelloides NBRC 4572: enzyme purification, functional characterization, and molecular cloning of the gene.

    PubMed

    Kato, Yasuo; Nomura, Taiji; Ogita, Shinjiro; Takano, Maki; Hoshino, Kazuhiro

    2013-12-01

    Two β-glucosidases (BGLs 1 and 2) were purified to homogeneity from the extracellular enzyme preparations of the ethanol-fermenting Mucor circinelloides NBRC 4572 statically grown on rice straw. BGLs 1 and 2 are monomeric glycoproteins whose apparent molecular masses (Ms) are around 78 kDa, which decreased by approximately 10 kDa upon enzymatic deglycosylation. Both BGLs showed similar enzyme characteristics in optimal temperature and pH, stability, and inhibitors. They were active against a wide range of aryl-β-glucosides and β-linked glucose oligosaccharides. Their amino acid sequences shared 81% identity and exhibited less than 60% identity with the known family-3 BGLs. Considering properties such as reduced inhibition by ethanol, glucose, and cellobiose, low transglucosylation activity, wider substrate range, less binding affinity to lignocellulosic materials, and abundant expression, BGL1 is likely to be more suitable for bioethanol production than BGL2 via simultaneous saccharification and fermentation of rice straw with M. circinelloides.

  14. Rapid identif ication and comparative analysis of chemical constituents in herbal medicine Fufang decoction by ultra-high-pressure liquid chromatography coupled with a hybrid linear ion trap-high-resolution mass spectrometry.

    PubMed

    Cao, Gang; Chen, Xiaocheng; Wu, Xin; Li, Qinglin; Zhang, Hongyan

    2015-05-01

    This study was conducted to reveal the relation between herbal medicine Fufang decoction and a single drug in terms of material base. Da-Cheng-Qi decoction (DCQD) was used as a model. Ultrahigh-pressure liquid chromatography coupled with a hybrid linear ion trap-high-resolution mass spectrometry (UHPLC-LTQ-Orbitrap) was applied to detect and identify the main chemical compounds. This technique was also employed to determine the different chemical components. Under optimized liquid chromatography and mass spectrometry conditions, 64 components, including iridoids, flavonoids, anthraquinones and coumarins, were separated and tentatively characterized in Da-Cheng-Qi decoction. After decoction, the contents of 18 compounds were markedly changed, and two components were no longer detected in Fufang decoction compared with single-medicine decoction. The established method provided a good example for the rapid identification of complicated polar constituents in herbal medicine prescriptions. Copyright © 2014 John Wiley & Sons, Ltd.

  15. Studies of charge transport in DNA films using the time-of-flight (TOF) technique

    NASA Astrophysics Data System (ADS)

    Yaney, Perry P.; Gorman, Timothy; Ouchen, Fahima; Grote, James G.

    2011-09-01

    Measurements were carried out on salmon DNA-based films, including as-received DNA (molecular weight, MW>2000 kDa) without and with hexacetyltrimethl-ammonium chloride (CTMA) surfactant, and sonicated DNA of MW~200 kDa with CTMA. The test specimens were spin-coated or drop-cast films on ITO-coated quartz slides with a gold charge-collecting electrode. To protect the films from atmospheric influences, the TOF devices were coated with a 200-400 nm polyurethane passivation layer. A quadrupled 20 ns, pulsed Nd:YAG laser with output at 266 nm was used for charge injection. The room temperature photoconductive transients were dispersive to varying degrees with hole mobilities in DNA materials films ranging between 2E-5 to 6E-3 cm2/Vs for fields ranging from 8 to 58 kV/cm. Only hole response was observed in DNA. The dispersive data were analyzed using a simple, quasi-empirical equation for the photocurrent transient data.

  16. Bathroom greywater recycling using polyelectrolyte-complex bilayer membrane: Advanced study of membrane structure and treatment efficiency.

    PubMed

    Oh, K S; Poh, P E; Chong, M N; Chan, E S; Lau, E V; Saint, C P

    2016-09-05

    Polyelectrolyte-complex bilayer membrane (PCBM) was fabricated using biodegradable chitosan and alginate polymers for subsequent application in the treatment of bathroom greywater. In this study, the properties of PCBMs were studied and it was found that the formation of polyelectrolyte network reduced the molecular weight cut-off (MWCO) from 242kDa in chitosan membrane to 2.71kDa in PCBM. The decrease in MWCO of PCBM results in better greywater treatment efficiency, subsequently demonstrated in a greywater filtration study where treated greywater effluent met the household reclaimed water standard of <2 NTU turbidity and <30ppm total suspended solids (TSS). In addition, a further 20% improvement in chemical oxygen demand (COD) removal was achieved as compared to a single layer chitosan membrane. Results from this study show that the biodegradable PCBM is a potential membrane material in producing clean treated greywater for non-potable applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Simultaneous/selective detection of dopamine and ascorbic acid at synthetic zeolite-modified/graphite-epoxy composite macro/quasi-microelectrodes.

    PubMed

    Ilinoiu, Elida Cristina; Manea, Florica; Serra, Pier Andrea; Pode, Rodica

    2013-06-03

    The present paper aims to miniaturize a graphite-epoxy and synthetic zeolite-modified graphite-epoxy composite macroelectrode as a quasi-microelectrode aiming in vitro and also, envisaging in vivo simultaneous electrochemical detection of dopamine (DA) and ascorbic acid (AA) neurotransmitters, or DA detection in the presence of AA. The electrochemical behavior and the response of the designed materials to the presence of dopamine and ascorbic acid without any protective membranes were studied by cyclic voltammetry and constant-potential amperometry techniques. The catalytic effect towards dopamine detection was proved for the synthetic zeolite-modified graphite-epoxy composite quasi-microelectrode, allowing increasing the sensitivity and selectivity for this analyte detection, besides a possible electrostatic attraction between dopamine cation and the negative surface of the synthetic zeolite and electrostatic repulsion with ascorbic acid anion. Also, the synthetic zeolite-modified graphite-epoxy composite quasi-microelectrode gave the best electroanalytical parameters for dopamine detection using constant-potential amperometry, the most useful technique for practical applications.

  18. Microscale diffusion measurements and simulation of a scaffold with a permeable strut.

    PubMed

    Lee, Seung Youl; Lee, Byung Ryong; Lee, Jongwan; Kim, Seongjun; Kim, Jung Kyung; Jeong, Young Hun; Jin, Songwan

    2013-10-10

    Electrospun nanofibrous structures provide good performance to scaffolds in tissue engineering. We measured the local diffusion coefficients of 3-kDa FITC-dextran in line patterns of electrospun nanofibrous structures fabricated by the direct-write electrospinning (DWES) technique using the fluorescence recovery after photobleaching (FRAP) method. No significant differences were detected between DWES line patterns fabricated with polymer supplied at flow rates of 0.1 and 0.5 mL/h. The oxygen diffusion coefficients of samples were estimated to be ~92%-94% of the oxygen diffusion coefficient in water based on the measured diffusion coefficient of 3-kDa FITC-dextran. We also simulated cell growth and distribution within spatially patterned scaffolds with struts consisting of either oxygen-permeable or non-permeable material. The permeable strut scaffolds exhibited enhanced cell growth. Saturated depths at which cells could grow to confluence were 15% deeper for the permeable strut scaffolds than for the non-permeable strut scaffold.

  19. Design of donor-acceptor copolymers for organic photovoltaic materials: a computational study.

    PubMed

    Turan, Haydar Taylan; Kucur, Oğuzhan; Kahraman, Birce; Salman, Seyhan; Aviyente, Viktorya

    2018-01-31

    80 different push-pull type organic chromophores which possess Donor-Acceptor (D-A) and Donor-Thiophene-Acceptor-Thiophene (D-T-A-T) structures have been systematically investigated by means of density functional theory (DFT) and time-dependent DFT (TD-DFT) at the B3LYP/6-311G* level. The introduction of thiophene (T) in the chain has allowed us to monitor the effect of π-spacers. Benchmark studies on the methodology have been carried out to predict the HOMO and LUMO energies and optical band gaps of the D-A systems accurately. The HOMO and LUMO energies and transition dipoles are seen to converge for tetrameric oligomers, and the latter have been used as optimal chain length to evaluate various geometrical and optoelectronic properties such as bond length alternations, distortion energies, frontier molecular orbital energies, reorganization energies and excited-state vertical transition of the oligomers. Careful analysis of our findings has allowed us to propose potential donor-acceptor couples to be used in organic photovoltaic cells.

  20. Correlation between the Open-Circuit Voltage and Charge Transfer State Energy in Organic Photovoltaic Cells.

    PubMed

    Zou, Yunlong; Holmes, Russell J

    2015-08-26

    In order to further improve the performance of organic photovoltaic cells (OPVs), it is essential to better understand the factors that limit the open-circuit voltage (VOC). Previous work has sought to correlate the value of VOC in donor-acceptor (D-A) OPVs to the interface energy level offset (EDA). In this work, measurements of electroluminescence are used to extract the charge transfer (CT) state energy for multiple small molecule D-A pairings. The CT state as measured from electroluminescence is found to show better correlation to the maximum VOC than EDA. The difference between EDA and the CT state energy is attributed to the Coulombic binding energy of the CT state. This correlation is demonstrated explicitly by inserting an insulating spacer layer between the donor and acceptor materials, reducing the binding energy of the CT state and increasing the measured VOC. These results demonstrate a direct correlation between maximum VOC and CT state energy.

  1. Evidence that a synthetic amyloid-ß oligomer-binding peptide (ABP) targets amyloid-ß deposits in transgenic mouse brain and human Alzheimer's disease brain.

    PubMed

    Chakravarthy, Balu; Ito, Shingo; Atkinson, Trevor; Gaudet, Chantal; Ménard, Michel; Brown, Leslie; Whitfield, James

    2014-03-14

    The synthetic ~5 kDa ABP (amyloid-ß binding peptide) consists of a region of the 228 kDa human pericentrioloar material-1 (PCM-1) protein that selectively and avidly binds in vitro Aβ1-42 oligomers, believed to be key co-drivers of Alzheimer's disease (AD), but not monomers (Chakravarthy et al., (2013) [3]). ABP also prevents Aß1-42 from triggering the apoptotic death of cultured human SHSY5Y neuroblasts, likely by sequestering Aß oligomers, suggesting that it might be a potential AD therapeutic. Here we support this possibility by showing that ABP also recognizes and binds Aβ1-42 aggregates in sections of cortices and hippocampi from brains of AD transgenic mice and human AD patients. More importantly, ABP targets Aβ1-42 aggregates when microinjected into the hippocampi of the brains of live AD transgenic mice. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

  2. Polydisulfide Manganese(II) Complexes as Non-Gadolinium Biodegradable Macromolecular MRI Contrast Agents

    PubMed Central

    Ye, Zhen; Jeong, Eun-Kee; Wu, Xueming; Tan, Mingqian; Yin, Shouyu; Lu, Zheng-Rong

    2011-01-01

    Purpose To develop safe and effective manganese(II) based biodegradable macromolecular MRI contrast agents. Materials and Methods In this study, we synthesized and characterized two polydisulfide manganese(II) complexes, Mn-DTPA cystamine copolymers and Mn-EDTA cystamine copolymers, as new biodegradable macromolecular MRI contrast agents. The contrast enhancement of the two manganese based contrast agents were evaluated in mice bearing MDA-MB-231 human breast carcinoma xenografts, in comparison with MnCl2. Results The T1 and T2 relaxivities were 4.74 and 10.38 mM−1s−1 per manganese at 3T for Mn-DTPA cystamine copolymers (Mn=30.50 kDa) and 6.41 and 9.72 mM−1s−1 for Mn-EDTA cystamine copolymers (Mn= 61.80 kDa). Both polydisulfide Mn(II) complexes showed significant liver, myocardium and tumor enhancement. Conclusion The manganese based polydisulfide contrast agents have a potential to be developed as alternative non-gadolinium contrast agents for MR cancer and myocardium imaging. PMID:22031457

  3. 75 FR 52292 - Airworthiness Directives; Diamond Aircraft Industries GmbH Models DA 40 and DA 40F Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-25

    ... Industries GmbH Models DA 40 and DA 40F Airplanes AGENCY: Federal Aviation Administration (FAA), Department... new airworthiness directive (AD) for all Diamond Aircraft Industries GmbH Models DA 40 and DA 40F... received information from Diamond Aircraft Industries GmbH that the Models DA 40 and DA 40F airplanes have...

  4. 77 FR 54800 - Airworthiness Directives; Diamond Aircraft Industries GmbH Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-06

    ... airworthiness directive (AD) for certain Diamond Aircraft Industries GmbH Models DA 42, DA 42 NG, and DA 42 M-NG... products. The MCAI states: During conversion of a DA 42 to a DA 42 NG, voids were detected in the adhesive... the following Diamond Aircraft Industries GmbH Models DA 42, DA 42 NG, and DA 42 M-NG airplanes...

  5. METHAMPHETAMINE-INDUCED NEUROTOXICITY DISRUPTS PHARMACOLOGICALLY EVOKED DOPAMINE TRANSIENTS IN THE DORSOMEDIAL AND DORSOLATERAL STRIATUM

    PubMed Central

    Robinson, John D.; Howard, Christopher D.; Pastuzyn, Elissa D.; Byers, Diane L.; Keefe, Kristen A.; Garris, Paul A.

    2014-01-01

    Phasic dopamine (DA) signaling, during which burst firing by dopamine neurons generates short-lived elevations in extracellular DA in terminal fields called DA transients, is implicated in reinforcement learning. Disrupted phasic DA signaling is proposed to link DA depletions and cognitive-behavioral impairment in methamphetamine (METH)-induced neurotoxicity. Here we further investigated this disruption by assessing effects of METH pretreatment on DA transients elicited by a drug cocktail of raclopride, a D2 DA receptor antagonist, and nomifensine, an inhibitor of the dopamine transporter (DAT). One advantage of this approach is that pharmacological activation provides a large, high-quality data set of transients elicited by endogenous burst firing of DA neurons for analysis of regional differences and neurotoxicity. These pharmacologically evoked DA transients were measured in the dorsomedial (DM) and dorsolateral (DL) striatum of urethane-anesthetized rats by fast-scan cyclic voltammetry. Electrically evoked DA levels were also recorded to quantify DA release and uptake, and DAT binding was determined by autoradiography to index DA denervation. Pharmacologically evoked DA transients in intact animals exhibited a greater amplitude and frequency and shorter duration in the DM compared to the DL striatum, despite similar pre- and post-drug assessments of DA release and uptake in both sub-regions as determined from the electrically evoked DA signals. METH pretreatment reduced transient activity. The most prominent effect of METH pretreatment on transients across striatal sub-region was decreased amplitude, which mirrored decreased DAT binding and was accompanied by decreased DA release. Overall, these results identify marked intrastriatal differences in the activity of DA transients that appear independent of presynaptic mechanisms for DA release and uptake and further support disrupted phasic DA signaling mediated by decreased DA release in rats with METH-induced neurotoxicity. PMID:24562969

  6. Thermal History Using Microparticle Trap Luminescence

    DTIC Science & Technology

    2012-06-01

    measurements were ~erformed using a Rise TL/ OSL -DA-15 reader. Irradiations were carried out using the integrated 0Sr/~0Y beta source delivering a...was obtained using LiF:Mg,Ti dosimeters of dimensions 3 mm x 3 mm x 0.9 mm. A 4-mm thick Kopp 5850 filter and a 3-mm thick HA3 filter were used in...C is one of the most sensitive TL and OSL material available with relatively well-known TL properties (McKeever et al., 1995). Furthermore, its

  7. Observations of ’Economical’ Fixed Prosthodontic Alloys,

    DTIC Science & Technology

    1982-01-01

    Office) 15. SECURITY CLASS. (of this ,.portj Ia. OS7RI~fl3 ~TATM~T1of5sA. DECLASSIFICATION/OO44GRAUTIV S Unlimited 17. 0137 PI3UT10ON STATEMENT (of the...however, the silver-palladium and silver-indium materials require ~DA~3 47 EOfl4O tO’/SfOBOLTE UNCLASSIFIED 8 2’ 02 R -/ SECURITY CLASSIFICATION OF...ous grain boundary netowrk , whereas those of Salivan revealed large grains, discontinuous grain boundaries and prominent subgrains. Microstructures

  8. Age-Related Decrements in the Muscarinic Enhancement of K(+)-Evoked Release of Endogenous Striatal Dopamine: An Indicator of Altered Cholinergic-Dopaminergic Reciprocal Inhibitory Control in Senescence

    DTIC Science & Technology

    1988-01-01

    oxotremorine , pilocarpine, carbachol or bethanecol) or nicotinic (nicotine) agonistt In some experiments DA autoreceptor function was assessed...muscarinic (e.g. oxotremorine , carbachol, be- studies using the ligand, [3H](-)-quinuclidinyl benzi- thanecol) or nicotinic (e.g. nicotine) agonists can... oxotremorine MATERIALS AND METHODS r or carbachol in striatal broken cell preparations pre- pared from young rats (6 months), these agents were Procedure

  9. Analysis of protein profiles in diabetic rat blood plasma that induced by alloxan

    NASA Astrophysics Data System (ADS)

    Hidayati, Dewi; Abdulgani, Nurlita; Setiyawan, Hengki; Trisnawati, Indah; Ashuri, Nova Maulidina; Sa'adah, Noor Nailis

    2017-06-01

    Proteomics is the study to identify the proteins involved in physiological metabolic pathway. The protein profiles of blood plasma from alloxan-induced diabetic rats has investigated using Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Data were analyzed descriptively based on variations of the type and intensity of the protein. There were identified the similarity of protein variant between diabetic and control rats included ankyrin (200kDa), IgG (150kDa), nephrin (136 kDa), IDE (112 kDA), albumin (66 kDa), prealbumin (55 kDA), CICP (43 kDa), ApoA-V (39 kDa), GAPDH (35 kDa), C-RP (27,1 kDa), leptin (16 kDa) and apelin (13 kDa). However, the apelin profile at diabetic rats shows the higher intensity than control.

  10. The sea urchin egg jelly coat consists of globular glycoproteins bound to a fibrous fucan superstructure.

    PubMed

    Bonnell, B S; Keller, S H; Vacquier, V D; Chandler, D E

    1994-03-01

    Intact egg jelly (EJ) coats surrounding eggs of the sea urchin Strongylocentrotus purpuratus were visualized in stereo images of platinum replicas produced by the quick-freeze, deep-etch, rotary-shadowing technique. The hydrated EJ coat forms an extensive fibrous network that makes contact with the vitelline layer at the egg surface. Fibers are decorated along their length with particles, particle density being highest in the interior regions of the coat. The macromolecular components making up the EJ network were visualized by rotary-shadowing of mica-adsorbed EJ samples. Whole EJ coats solubilized in pH 5 sea-water and spread on the mica surface consist of complex networks of branching fibers decorated with large patches of amorphous material. As we have previously shown (Keller and Vacquier, 1994), EJ boiled in a dissolution buffer containing SDS and beta-mercaptoethanol and applied to a Sephacryl-500 gel filtration column can be separated into three fractions: a 380-kDa fucose sulfate polymer (FSP), which elutes in the void volume, and two column-included fractions consisting of intermediate (300 kDa) and low-molecular-weight (30- to 138-kDa) glycoproteins. Rotary-shadowing of the FSP fraction reveals branched fibrous components similar in appearance to that of solubilized whole EJ but devoid of any particulate decoration. In contrast, intermediate- and low-molecular-weight EJ components are strictly globular in appearance but are distinguishable on the basis of size. Ion-exchange purification of whole EJ yields two glycoproteins, of 82 and 138 kDa, having AR-inducing activity (Keller and Vacquier, 1994). Platinum replication shows these active components to be small spherical molecules about 8 nm in diameter. The above fractionation scheme requires harsh dissociation conditions. Indeed, if EJ is not boiled in SDS buffer before fractionation, the 300-kDa fraction and the FSP appear together in the void volume. Rotary-shadowing of this complex reveals a multistranded polymer, decorated with glycoproteins at specific kink points. Taken together, our data suggest that the EJ network is composed of a fucose sulfate polymer superstructure to which glycoproteins are bound.

  11. Molluscan mega-hemocyanin: an ancient oxygen carrier tuned by a ~550 kDa polypeptide

    PubMed Central

    2010-01-01

    Background The allosteric respiratory protein hemocyanin occurs in gastropods as tubular di-, tri- and multimers of a 35 × 18 nm, ring-like decamer with a collar complex at one opening. The decamer comprises five subunit dimers. The subunit, a 400 kDa polypeptide, is a concatenation of eight paralogous functional units. Their exact topology within the quaternary structure has recently been solved by 3D electron microscopy, providing a molecular model of an entire didecamer (two conjoined decamers). Here we study keyhole limpet hemocyanin (KLH2) tridecamers to unravel the exact association mode of the third decamer. Moreover, we introduce and describe a more complex type of hemocyanin tridecamer discovered in fresh/brackish-water cerithioid snails (Leptoxis, Melanoides, Terebralia). Results The "typical" KLH2 tridecamer is partially hollow, whereas the cerithioid tridecamer is almost completely filled with material; it was therefore termed "mega-hemocyanin". In both types, the staggering angle between adjoining decamers is 36°. The cerithioid tridecamer comprises two typical decamers based on the canonical 400 kDa subunit, flanking a central "mega-decamer" composed of ten unique ~550 kDa subunits. The additional ~150 kDa per subunit substantially enlarge the internal collar complex. Preliminary oxygen binding measurements indicate a moderate hemocyanin oxygen affinity in Leptoxis (p50 ~9 mmHg), and a very high affinity in Melanoides (~3 mmHg) and Terebralia (~2 mmHg). Species-specific and individual variation in the proportions of the two subunit types was also observed, leading to differences in the oligomeric states found in the hemolymph. Conclusions In cerithioid hemocyanin tridecamers ("mega-hemocyanin") the collar complex of the central decamer is substantially enlarged and modified. The preliminary O2 binding curves indicate that there are species-specific functional differences in the cerithioid mega-hemocyanins which might reflect different physiological tolerances of these gill-breathing animals. The observed differential expression of the two subunit types of mega-hemocyanin might allow individual respiratory acclimatization. We hypothesize that mega-hemocyanin is a key character supporting the adaptive radiation and invasive capacity of cerithioid snails. PMID:20465844

  12. Analysis of the mechanisms by which amphetamine releases dopamine from striatal dopaminergic neurons

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parker, E.M.

    1987-01-01

    The goals of the studies were (1) to determine the intraneuronal transmitter pools that contribute to the efflux of dopamine (DA) elicited by amphetamine (AMPH) and (2) to determine the biochemical mechanism by which AMPH increases DA efflux from dopaminergic neurons. AMPH increased the efflux of endogenous DA and decreased the electrically-evoked overflow of (/sup 3/H) acetylcholine (ACh) from superfused rabbit striatal slices. These effects were most pronounced when both vesicular DA stores and DA synthesis were intact. Therefore, extravesicular, newly synthesized DA and vesicular stores of DA contribute to AMPH-induced DA efflux. Simultaneous inhibition of monoamine oxidase (MAO) andmore » neuronal DA uptake did not increase the efflux of endogenous DA or inhibit the electrically-evoked overflow of (/sup 3/H)ACh to the same extent as AMPH. Hence, inhibition of MAO and neuronal DA uptake are probably not the major mechanisms by which AMPH increases DA efflux. The AMPH-induced efflux of endogenous or (/sup 3/H)DA was blocked by inhibitors of neuronal DA uptake.« less

  13. The major histocompatibility complex genes impact pain response in DA and DA.1U rats.

    PubMed

    Guo, Yuan; Yao, Fan-Rong; Cao, Dong-Yuan; Li, Li; Wang, Hui-Sheng; Xie, Wen; Zhao, Yan

    2015-08-01

    Our recent studies have shown that the difference in basal pain sensitivity to mechanical and thermal stimulation between Dark-Agouti (DA) rats and a novel congenic DA.1U rats is major histocompatibility complex (MHC) genes dependent. In the present study, we further used DA and DA.1U rats to investigate the role of MHC genes in formalin-induced pain model by behavioral, electrophysiological and immunohistochemical methods. Behavioral results showed biphasic nociceptive behaviors increased significantly following the intraplantar injection of formalin in the hindpaw of DA and DA.1U rats. The main nociceptive behaviors were lifting and licking, especially in DA rats (P<0.001 and P<0.01). The composite pain scores (CPS) in DA rats were significantly higher than those in DA.1U rats in both phases of the formalin test (P<0.01). Electrophysiological results also showed the biphasic increase in discharge rates of C and Aδ fibers of L5 dorsal root in the two strains, and the net change of the discharge rate of DA rats was significantly higher than that of DA.1U rats (P<0.05). The mechanical thresholds decreased after formalin injection in both strains (P<0.01), and the net change in the mechanical threshold in DA was greater than that in DA.1U rats (P<0.05). The expression of RT1-B, representation of MHC class II molecule, in laminae I-II of L4/5 spinal cord in DA rats was significantly higher than that in DA.1U rats in the respective experimental group (P<0.05). These results suggested that both DA and DA.1U rats exhibited nociceptive responses in formalin-induced pain model and DA rats were more sensitive to noxious chemical stimulus than DA.1U rats, indicating that MHC genes might contribute to the difference in pain sensitivity. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. The local effect of octreotide on mechanical pain sensitivity is more sensitive in DA rats than DA.1U rats.

    PubMed

    Yao, Fan-Rong; Wang, Hui-Sheng; Guo, Yuan; Zhao, Yan

    2016-02-01

    A recent study by the authors indicated that major histocompatibility complex (MHC) genes are associated with the differences in basal pain sensitivity and in formalin model between Dark-Agouti (DA) and novel congenic DA.1U rats, which have the same genetic background as DA rats except for the u alleles of MHC. The objective of the present study is to investigate whether there is a difference in the pristane-induced arthritis (PIA) model and local analgesic effect of octreotide (OCT) between DA and DA.1U rats. The hindpaw mechanical withdrawal threshold (MWT) and heat withdrawal latency (HWL) were observed. The C unit firings of the tibial nerve evoked by non-noxious and noxious toe movements were recorded by electrophysiological methods in normal and PIA models in DA and DA.1U rats before and after local OCT administration. The expression of somatostatin receptor 2A (SSTR2A) was observed by immunohistochemistry. The results demonstrate that DA rats have a higher mechanical sensitivity than DA.1U rats after PIA. Local OCT administration significantly elevated MWT in DA rats under normal and PIA sate, but not in DA.1U rats. The electrophysiological experiments showed OCT significantly attenuated the firings of C units evoked by non-noxious and noxious stimulation in DA rats more than those in DA.1U rats both in normal and PIA states. In addition, the expression of SSTR2A in the dorsal horn of the spinal cord was significantly higher in DA than in DA.1U rats. All of the findings suggest a higher local analgesic effect of OCT in DA rats than DA.1U rats, which might be associated with the MHC genes. © 2016 John Wiley & Sons Australia, Ltd.

  15. METHAMPHETAMINE-INDUCED NEUROTOXICITY DISRUPTS NATURALLY OCCURRING PHASIC DOPAMINE SIGNALING

    PubMed Central

    Howard, Christopher D.; Daberkow, David P.; Ramsson, Eric S.; Keefe, Kristen A.; Garris, Paul A.

    2013-01-01

    Methamphetamine (METH) is a highly addictive drug that is also neurotoxic to central dopamine (DA) systems. Although striatal DA depletions induced by METH are associated with behavioral and cognitive impairments, the link between these phenomena remains poorly understood. Previous work in both METH-pretreated animals and the 6-hydroxydopamine model of Parkinson’s disease suggests that a disruption of phasic DA signaling, which is important for learning and goal-directed behavior, may be such a link. However, prior studies used electrical stimulation to elicit phasic-like DA responses and were also performed under anesthesia, which alters DA neuron activity and presynaptic function. Here we investigated the consequences of METH-induced DA terminal loss on both electrically evoked phasic-like DA signals and so-called “spontaneous” phasic DA transients measured by voltammetry in awake rats. Not ostensibly attributable to discrete stimuli, these sub-second DA changes may play a role in enhancing reward-cue associations. METH-pretreatment reduced tissue DA content in the dorsomedial striatum and nucleus accumbens by ~55%. Analysis of phasic-like DA responses elicited by reinforcing stimulation revealed that METH pretreatment decreased their amplitude and underlying mechanisms for release and uptake to a similar degree as DA content in both striatal subregions. Most importantly, characteristics of DA transients were altered by METH-induced DA terminal loss, with amplitude and frequency decreased and duration increased. These results demonstrate for the first time that denervation of DA neurons alters naturally occurring DA transients and are consistent with diminished phasic DA signaling as a plausible mechanism linking METH-induced striatal DA depletions and cognitive deficits. PMID:23574406

  16. Transformation of organic carbon, trace element, and organo-mineral colloids in the mixing zone of the largest European Arctic river

    NASA Astrophysics Data System (ADS)

    Pokrovsky, O. S.; Shirokova, L. S.; Viers, J.; Gordeev, V. V.; Shevchenko, V. P.; Chupakov, A. V.; Vorobieva, T. Y.; Candaudap, F.; Casseraund, C.; Lanzanova, A.; Zouiten, C.

    2013-10-01

    The estuarine behavior of organic carbon (OC) and trace elements (TE) was studied for the largest European sub-Arctic river, which is the Severnaya Dvina; this river is a deltaic estuary covered in ice during several hydrological seasons: summer (July 2010, 2012) and winter (March 2009) baseflow, and the November-December 2011 ice-free period. Colloidal forms of OC and TE were assessed using three pore size cutoff (1, 10, and 50 kDa) using an in-situ dialysis procedure. Conventionally dissolved (< 0.22 μm) fractions demonstrated clear conservative behavior for Li, B, Na, Mg, K, Ca, Sr, Mo, Rb, Cs, and U during the mixing of freshwater with the White Sea; a significant (up to a factor of 10) concentration increase occurs with increases in salinity. Si and OC also displayed conservative behavior but with a pronounced decrease of concentration seawards. Rather conservative behavior, but with much smaller changes in concentration (variation within ±30%) over a full range of salinities, was observed for Ti, Ni, Cr, As, Co, Cu, Ga, Y, and heavy REE. Strong non-conservative behavior with coagulation/removal at low salinities (< 5‰) was exhibited by Fe, Al, Zr, Hf, and light REE. Finally, certain divalent metals exhibited non-conservative behavior with a concentration gain at low (~2-5‰, Ba, Mn) or intermediate (~10-15‰, Ba, Zn, Pb, Cd) salinities, which is most likely linked to TE desorption from suspended matter or sediment outflux. The most important result of this study is the elucidation of the behavior of the "truly" dissolved low molecular weight LMW< 1 kDa fraction containing Fe, OC, and a number of insoluble elements. The concentration of the LMW fraction either remains constant or increases its relative contribution to the overall dissolved (< 0.22 μm) pool as the salinity increases. Similarly, the relative proportion of colloidal (1 kDa-0.22 μm) pool for the OC and insoluble TE bound to ferric colloids systematically decreased seaward, with the largest decrease occurring at low (< 5‰) salinities. Overall, the observed decrease of the colloidal fraction may be related to the coagulation of organo-ferric colloids at the beginning of the mixing zone and therefore the replacement of the HMW1 kDa-0.22 μm portion by the LMW< 1 kDa fraction. These patterns are highly reproducible across different sampling seasons, suggesting significant enrichment of the mixing zone by the most labile (and potentially bioavailable) fraction of the OC, Fe and insoluble TE. The size fractionation of the colloidal material during estuarine mixing reflects a number of inorganic and biological processes, the relative contribution of which to element speciation varies depending on the hydrological stage and time of year. In particular, LMW< 1 kDa ligand production in the surface horizons of the mixing zone may be linked to heterotrophic mineralization of allochthonous DOM and/or photodestruction. Given the relatively low concentration of particulate vs. dissolved load of most trace elements, desorption from the river suspended material was less pronounced than in other rivers in the world. As a result, the majority of dissolved components exhibited either a conservative (OC and related elements such as divalent metals) or non-conservative, coagulation-controlled (Fe, Al, and insoluble TE associated with organo-ferric colloids) behavior. The climate warming in high latitudes is likely to intensify the production of LMW< 1 kDa organic ligands and the associated TE; therefore, the delivery of potentially bioavailable trace metal micronutrients from the land to the ocean may increase.

  17. Somatodendritic dopamine release: recent mechanistic insights

    PubMed Central

    Rice, Margaret E.; Patel, Jyoti C.

    2015-01-01

    Dopamine (DA) is a key transmitter in motor, reward and cogitative pathways, with DA dysfunction implicated in disorders including Parkinson's disease and addiction. Located in midbrain, DA neurons of the substantia nigra pars compacta project via the medial forebrain bundle to the dorsal striatum (caudate putamen), and DA neurons in the adjacent ventral tegmental area project to the ventral striatum (nucleus accumbens) and prefrontal cortex. In addition to classical vesicular release from axons, midbrain DA neurons exhibit DA release from their cell bodies and dendrites. Somatodendritic DA release leads to activation of D2 DA autoreceptors on DA neurons that inhibit their firing via G-protein-coupled inwardly rectifying K+ channels. This helps determine patterns of DA signalling at distant axonal release sites. Somatodendritically released DA also acts via volume transmission to extrasynaptic receptors that modulate local transmitter release and neuronal activity in the midbrain. Thus, somatodendritic release is a pivotal intrinsic feature of DA neurons that must be well defined in order to fully understand the physiology and pathophysiology of DA pathways. Here, we review recent mechanistic aspects of somatodendritic DA release, with particular emphasis on the Ca2+ dependence of release and the potential role of exocytotic proteins. PMID:26009764

  18. Nicotine- and methamphetamine-induced dopamine release evaluated with in-vivo binding of radiolabelled raclopride to dopamine D2 receptors: comparison with in-vivo microdialysis data.

    PubMed

    Kim, Sang Eun; Han, Seung-Moo

    2009-07-01

    The effect of substances which alter extracellular dopamine (DA) concentration has been studied by measuring changes in the binding of radiolabelled raclopride, a DA D2 receptor ligand that is sensitive to endogenous DA. To better characterize the relationship between extracellular DA concentration and DA D2 receptor binding of raclopride, we compared the changes of extracellular DA concentration (measured using in-vivo microdialysis) and in-vivo [3H]raclopride binding induced by different doses of methamphetamine (Meth) and nicotine, drugs that enhance DA release with and without blocking DA transporters (DATs), respectively, in rat striatum. Nicotine elicited a modest increase of striatal extrasynaptic extracellular DA, while Meth produced a marked increase of striatal extrasynaptic DA in a dose-dependent manner. There was a close correlation between the decrease in [3H]raclopride in-vivo binding and the increase in extrasynaptic DA concentration induced by both nicotine (r2=0.95, p<0.001) and Meth (r2=0.98, p=0.001), supporting the usefulness of the radiolabelled raclopride-binding measurement for the non-invasive assessment of DA release following interventions in the living brain. However, the linear regression analysis revealed that the ratio of percent DA increase to percent [3H]raclopride binding reduction was 25-fold higher for Meth (34.8:1) than for nicotine (1.4:1). The apparent discrepancy in the extrasynaptic DA-[3H]raclopride binding relationship between the DA-enhancing drugs with and without DAT-blocking property indicates that the competition between endogenous DA and radiolabelled raclopride takes place at the intrasynaptic rather than extrasynaptic DA D2 receptors and reflects synaptic concentration of DA.

  19. Effective tobacco control measures: agreement among medical students.

    PubMed

    Martins, Stella Regina; Paceli, Renato Batista; Bussacos, Marco Antônio; Fernandes, Frederico Leon Arrabal; Prado, Gustavo Faibischew; Lombardi, Elisa Maria Siqueira; Terra-Filho, Mário; Santos, Ubiratan Paula

    2017-01-01

    To determine the level of agreement with effective tobacco control measures recommended by the World Health Organization and to assess the attitudes toward, knowledge of, and beliefs regarding smoking among third-year medical students at University of São Paulo School of Medicine, located in the city of São Paulo, Brazil. Between 2008 and 2012, all third-year medical students were invited to complete a self-administered questionnaire based on the Global Health Professionals Student Survey and its additional modules. The study sample comprised 556 students. The level of agreement with the World Health Organization recommendations was high, except for the components "received smoking cessation training" and "raising taxes is effective to reduce the prevalence of smoking". Most of the students reported that they agree with banning tobacco product sales to minors (95%), believe that physicians are role models to their patients (84%), and believe that they should advise their patients to quit cigarette smoking (96%) and using other tobacco products (94%). Regarding smoking cessation methods, most of the students were found to know more about nicotine replacement therapy than about non-nicotine therapies (93% vs. 53%). Only 37% of the respondents were aware of the importance of educational antismoking materials, and only 31% reported that they believe in the effectiveness of encouraging their patients, during medical visits. In our sample, the prevalence of current cigarette smoking was 5.23%; however, 43.82% of the respondents reported having experimented with water-pipe tobacco smoking. Our results revealed the need to emphasize to third-year medical students the importance of raising the prices of and taxes on tobacco products. We also need to make students aware of the dangers of experimenting with tobacco products other than cigarettes, particularly water-pipe tobacco smoking. Determinar o grau de concordância com medidas eficazes de controle do tabaco recomendadas pela Organização Mundial da Saúde e avaliar as atitudes, o conhecimento e as crenças a respeito do tabagismo em alunos do terceiro ano de medicina da Faculdade de Medicina da Universidade de São Paulo, em São Paulo (SP). Entre 2008 e 2012, todos os alunos do terceiro ano de medicina foram convidados a preencher um questionário autoaplicável baseado na Global Health Professions Student Survey e em seus módulos adicionais. A amostra consistiu em 556 estudantes. O grau de concordância com as recomendações da Organização Mundial da Saúde foi alto, à exceção de "receberam treinamento a respeito de cessação do tabagismo" e "aumentar os impostos é uma medida eficaz para reduzir a prevalência do tabagismo". A maioria dos estudantes relatou que concorda com a proibição da venda de produtos do tabaco a menores de idade (95%), acredita que os médicos são modelos de comportamento para seus pacientes (84%) e acredita que deveriam aconselhar seus pacientes a parar de fumar cigarros (96%) e de usar outros produtos do tabaco (94%). No tocante aos métodos de cessação do tabagismo, observamos que a maioria dos estudantes sabe mais sobre terapia de reposição da nicotina do que sobre terapias não nicotínicas (93% vs. 53%). Apenas 37% dos participantes estavam cientes da importância de material educacional antitabagismo, e apenas 31% relataram que acreditam na eficácia de incentivar seus pacientes, durante as consultas médicas, a parar de fumar. Em nossa amostra, a prevalência de tabagismo atual foi de 5,23%; entretanto, 43,82% dos participantes relataram ter experimentado fumar tabaco com um narguilé. Nossos resultados revelaram a necessidade de deixar claro para os alunos do terceiro ano de medicina o quão importante é aumentar os preços e impostos dos produtos do tabaco. É também preciso conscientizar os alunos dos perigos de experimentar outros produtos do tabaco que não os cigarros, particularmente o narguilé.

  20. Microbial conversion of low-rank coal: characterization of biodegraded product

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilson, B.W.; Bean, R.M.; Franz, J.A.

    The authors have characterized products obtained from the action of the fungus Polyporus versicolor on oxidized North Dakota (ND) lignite. These analyses showed that, compared to feed coal, the bioconverted materials had higher hydrogen:carbon and oxygen:carbon ratios, but were proportionately lower in aliphatic hydrogen, as determined by infrared (IR) spectroscopy. The acid-precipitated extract was dissolved in dilute base and analyzed by /sup 13/C nuclear magnetic resonance (NMR) spectroscopy. Of the 60% of the carbon accounted for, approximately 51% of the carbon atoms were aromatic, 20% were assigned to carboxylic acid groups, and the remainder were aliphatic carbon. Proton NMR spectramore » of the acid-precipitated material revealed approximately equal proportions of aromatic and aliphatic hydrogen. The bioconverted materials were highly polar and exhibited a wide range in apparent molecular weight; most material was over 10,000 Da at acidic pH, as determined by ultrafiltration experiments. Freeze-dried product material was soluble in water but was essentially insoluble in other organic solvents. Calorimetric measurements on samples of the freeze-dried extract showed that, on a per-weight basis, it retained 94-97% of the heating value of the feed coal. 12 references, 5 figures, 2 tables.« less

  1. Role of high molecular mass organics in colour formation during biological treatment of pulp and paper wastewater.

    PubMed

    Milestone, C B; Stuthridge, T R; Fulthorpe, R R

    2007-01-01

    This paper forms part of series of biological treatment colour behaviour studies. Surveys across a range of mills have observed colour increases in aerated stabilisation basins of 20-45%. Much of the colour formation has been demonstrated to occur in high molecular mass effluent organic constituents (HMM) present in bleach plant effluents. Removing material greater than 3000 Da essentially eliminated the colour forming ability in both E and D stage wastewaters. We have also shown that pulp and paper sludges contain anaerobic bacteria capable of reducing humic like materials. Colour formation was correlated to the anoxic conditions and the availability of readily biodegradable organic constituents during the wastewater treatment process. Overall, these studies suggest that colour formation in pulp and paper biological treatment systems may be caused by anaerobic bacteria using HMM material from the bleaching effluents as an electron acceptor for growth. This leads to the reduction of the material, which in turn leads to non-reversible internal changes, such as intra-molecular polymerisation or formation of chromophoric functional groups.

  2. Identification of organic hydroperoxides and peroxy acids using atmospheric pressure chemical ionization-tandem mass spectrometry (APCI-MS/MS): application to secondary organic aerosol

    NASA Astrophysics Data System (ADS)

    Zhou, Shouming; Rivera-Rios, Jean C.; Keutsch, Frank N.; Abbatt, Jonathan P. D.

    2018-05-01

    Molecules with hydroperoxide functional groups are of extreme importance to both the atmospheric and biological chemistry fields. In this work, an analytical method is presented for the identification of organic hydroperoxides and peroxy acids (ROOH) by direct infusion of liquid samples into a positive-ion atmospheric pressure chemical ionization-tandem mass spectrometer ((+)-APCI-MS/MS). Under collisional dissociation conditions, a characteristic neutral loss of 51 Da (arising from loss of H2O2+NH3) from ammonium adducts of the molecular ions ([M + NH4]+) is observed for ROOH standards (i.e. cumene hydroperoxide, isoprene-4-hydroxy-3-hydroperoxide (ISOPOOH), tert-butyl hydroperoxide, 2-butanone peroxide and peracetic acid), as well as the ROOH formed from the reactions of H2O2 with aldehydes (i.e. acetaldehyde, hexanal, glyoxal and methylglyoxal). This new ROOH detection method was applied to methanol extracts of secondary organic aerosol (SOA) material generated from ozonolysis of α-pinene, indicating a number of ROOH molecules in the SOA material. While the full-scan mass spectrum of SOA demonstrates the presence of monomers (m/z = 80-250), dimers (m/z = 250-450) and trimers (m/z = 450-600), the neutral loss scan shows that the ROOH products all have masses less than 300 Da, indicating that ROOH molecules may not contribute significantly to the SOA oligomeric content. We anticipate this method could also be applied to biological systems with considerable value.

  3. Age-related changes in dopamine signaling in Nurr1 deficient mice as a model of Parkinson’s disease

    PubMed Central

    Zhang, Lifen; Le, Weidong; Xie, Wenjie; Dani, John A.

    2011-01-01

    The nuclear receptor related 1 (Nurr1) transcription factor contributes to the development and maintenance of dopamine (DA) neurons in the brain. We found that heterozygous Nurr1 knock-out (Nurr1 +/−) influenced the age-dependent decline in the number of DA neurons and influenced DA signaling. We examined the DA marker, tyrosine hydroxylase, using immunohistochemistry, and we measured DA signaling using fast-scan cyclic voltammetry in 3 age groups of wild-type (Nurr1 +/+) and mutant (Nurr1 +/−) mice: 3–6, 9–12, and 15–23 months old. Prior to significant loss of DA neurons and to the onset of parkinsonian symptoms, young Nurr1 +/− mice (3–6 months) exhibited a decrease in peak evoked DA release that was partially countered by a decrease in the rate of DA reuptake. As peak evoked DA release declined with age for both the wild-type and Nurr1 +/− mice, both genotypes manifested decreased DA reuptake. As the DA release fell further with age, decreased DA reuptake eventually could not adequately compensate the Nurr1 +/− mice. The results indicated that Nurr1 deficiency led to impaired DA release even before significant DA neuron loss. PMID:21531044

  4. Bromine- and chlorine-containing aeruginosins from Microcystis aeruginosa bloom material collected in Kibbutz Geva, Israel.

    PubMed

    Elkobi-Peer, Shira; Faigenbaum, Raya; Carmeli, Shmuel

    2012-12-28

    Five new natural products, aeruginosins GE686 (1), GE766 (2), GE730 (3), GE810 (4), and GE642 (5), were isolated along with four known aeruginosins, 98C, 101, KY642, and DA688, from bloom material of the cyanobacterium Microcystis aeruginosa collected from a fish pond in Kibbutz Geva, Israel, in August 2007. Their structures were elucidated by a combination of various spectroscopic techniques, primarily NMR and MS, while the absolute configurations of the stereogenic centers were determined by Marfey's and chiral-phase HPLC methods. Two of the new aeruginosins, aeruginosins GE686 (1) and GE766 (2), contain the unprecedented d-m-Br-m'-Cl-p-hydroxyphenyllactic acid derivative. The structures and biological activities of the five new metabolites are described.

  5. Giant first hyperpolarizabilities of donor-acceptor substituted graphyne: An ab initio study.

    PubMed

    Chakraborti, Himadri

    2016-01-15

    Graphyne (Gy), a theoretically proposed material, has been utilized, for the first time, in a phenomenal donor-Gy-acceptor (D-Gy-A) structure to plan a superior nonlinear optical material. Owing to the extraordinary character of graphyne, this conjugate framework shows strikingly extensive static first hyperpolarizability (β(tot)) up to 128×10(-30) esu which is an enormous improvement than that of the bare graphyne. The donor-acceptor separation plays a key role in the change of β(tot) value. The π-conjugation of graphyne backbone has spread throughout some of the D-A attached molecules and leads to a low band gap state. Finally, two level model clarifies that the molecule having low transition energy should have high first hyperpolarizability. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Soft Polymers for Building up Small and Smallest Blood Supplying Systems by Stereolithography

    PubMed Central

    Meyer, Wolfdietrich; Engelhardt, Sascha; Novosel, Esther; Elling, Burkhard; Wegener, Michael; Krüger, Hartmut

    2012-01-01

    Synthesis of a homologous series of photo-polymerizable α,ω-polytetrahydrofuranether-diacrylate (PTHF-DA) resins is described with characterization by NMR, GPC, DSC, soaking and rheometrical measurements. The curing speeds of the resins are determined under UV light exposure. Young’s modulus and tensile strength of fully cured resins show flexible to soft material attributes dependent on the molar mass of the used linear PTHF-diacrylates. Structuring the materials by stereo lithography (SL) and multiphoton polymerization (MPP) leads to tubes and bifurcated tube systems with a diameter smaller than 2 mm aimed at small to smallest supplying systems with capillary dimensions. WST-1 biocompatibility tests ofm polymer extracts show nontoxic characteristics of the adapted polymers after a washing process. Some polymers show shape memory effect (SME). PMID:24955530

  7. Autocorrelation descriptor improvements for QSAR: 2DA_Sign and 3DA_Sign

    NASA Astrophysics Data System (ADS)

    Sliwoski, Gregory; Mendenhall, Jeffrey; Meiler, Jens

    2016-03-01

    Quantitative structure-activity relationship (QSAR) is a branch of computer aided drug discovery that relates chemical structures to biological activity. Two well established and related QSAR descriptors are two- and three-dimensional autocorrelation (2DA and 3DA). These descriptors encode the relative position of atoms or atom properties by calculating the separation between atom pairs in terms of number of bonds (2DA) or Euclidean distance (3DA). The sums of all values computed for a given small molecule are collected in a histogram. Atom properties can be added with a coefficient that is the product of atom properties for each pair. This procedure can lead to information loss when signed atom properties are considered such as partial charge. For example, the product of two positive charges is indistinguishable from the product of two equivalent negative charges. In this paper, we present variations of 2DA and 3DA called 2DA_Sign and 3DA_Sign that avoid information loss by splitting unique sign pairs into individual histograms. We evaluate these variations with models trained on nine datasets spanning a range of drug target classes. Both 2DA_Sign and 3DA_Sign significantly increase model performance across all datasets when compared with traditional 2DA and 3DA. Lastly, we find that limiting 3DA_Sign to maximum atom pair distances of 6 Å instead of 12 Å further increases model performance, suggesting that conformational flexibility may hinder performance with longer 3DA descriptors. Consistent with this finding, limiting the number of bonds in 2DA_Sign from 11 to 5 fails to improve performance.

  8. Data Administration at a Regional University: A Case Study.

    ERIC Educational Resources Information Center

    Gose, Frank J.

    Data administration (DA) is a position that has emerged with the growth of information technologies. A review of DA literature confirms that, although DA is widely associated with database management systems (DBMS), there is no standard DA job description, DA staffing and location within the organization vary, and DA functions range in description…

  9. From sanddabs to blue whales: the pervasiveness of domoic acid.

    PubMed

    Lefebvre, Kathi A; Bargu, Sibel; Kieckhefer, Tom; Silver, Mary W

    2002-07-01

    Domoic acid (DA) is a potent food web transferred algal toxin that has caused dramatic mortality events involving sea birds and sea lions. Although no confirmed DA toxicity events have been reported in whales, here we present data demonstrating that humpback and blue whales are exposed to the toxin and consume DA contaminated prey. Whale fecal samples were found to contain DA at levels ranging from 10 to 207microg DA g(-1) feces via HPLC-UV methods. SEM analysis of whale feces containing DA, collected from krill-feeding whales, revealed the presence of diatom frustules identified as Pseudo-nitzschia australis, a known DA producer. Humpback whales were observed feeding on anchovies and sardines that contained DA at levels ranging from 75 to 444microg DA g(-1) viscera. DA contamination of whale feces and fish occurred only during blooms of toxic Pseudo-nitzschia. Additionally, several novel fish species collected during a toxic diatom bloom were tested for DA. Fish as diverse as benthic sanddabs and pelagic albacore were found to contain the neurotoxin, suggesting that DA permeates benthic as well as pelagic communities.

  10. Two forms of Vibrio cholerae O1 El Tor hemolysin derived from identical precursor protein.

    PubMed

    Ikigai, H; Ono, T; Nakae, T; Otsuru, H; Shimamura, T

    1999-01-08

    Vibrio cholerae O1 grown in heart infusion broth produces two forms of El Tor hemolysin (ETH) monomers of 65 and 50 kDa. These monomers form several different sizes of mixed oligomers ranging from 180 to 280 kDa in the liposomal membranes. We found that the N-terminal amino acid sequences, NH2-Trp-Pro-Ala-Pro-Ala-Asn-Ser-Glu, of both the 65- and 50-kDa toxins were identical. We assumed, therefore, that the 65- and 50-kDa toxins were derivatives of the identical precursor protein and the 50-kDa protein was a truncated derivative of 65-kDa ETH. To substantiate this assumption, we treated the 260-kDa oligomer with trypsin and obtained a 190-kDa oligomer. This 190-kDa oligomer consisted of only the 50-kDa subunits. Both 260- and 190-kDa oligomers formed ion channels indistinguishable from each other in planar lipid bilayers. These results suggest that the essential part of the ETH in forming the membrane-damaging aggregate is a 50-kDa protein.

  11. Evaluation of the Efficacy and Safety of DA-9601 versus Its New Formulation, DA-5204, in Patients with Gastritis: Phase III, Randomized, Double-Blind, Non-Inferiority Study.

    PubMed

    Choi, Yoon Jin; Lee, Dong Ho; Choi, Myung Gyu; Lee, Sung Joon; Kim, Sung Kook; Song, Geun Am; Rhee, Poong Lyul; Jung, Hwoon Yong; Kang, Dae Hwan; Lee, Yong Chan; Lee, Si Hyung; Choi, Suck Chei; Shim, Ki Nam; Seol, Sang Yong; Moon, Jeong Seop; Shin, Yong Woon; Kim, Hyun Soo; Lee, Soo Teik; Cho, Jin Woong; Choi, Eun Kwang; Lee, Oh Young; Jang, Jin Seok

    2017-11-01

    This study compared the efficacy of DA-9601 (Dong-A ST Co., Seoul, Korea) and its new formulation, DA-5204 (Dong-A ST Co.), for treating erosive gastritis. This phase III, randomized, multicenter, double-blind, non-inferiority trial randomly assigned 434 patients with endoscopically proven gastric mucosal erosions into two groups: DA-9601 3 times daily or DA-5,204 twice daily for 2 weeks. The final analysis included 421 patients (DA-5204, 209; DA-9601, 212). The primary endpoint (rate of effective gastric erosion healing) and secondary endpoints (cure rate of endoscopic erosion and gastrointestinal [GI] symptom relief) were assessed using endoscopy after the treatment. Drug-related adverse events (AEs), including GI symptoms, were also compared. At week 2, gastric healing rates with DA-5204 and DA-9601 were 42.1% (88/209) and 42.5% (90/212), respectively. The difference between the groups was -0.4% (95% confidence interval, -9.8% to 9.1%), which was above the non-inferiority margin of -14%. The cure rate of gastric erosion in both groups was 37.3%. The improvement rates of GI symptoms with DA-5204 and DA-9601 were 40.4% and 40.8%, respectively. There were no statistically significant differences between the two groups in both secondary endpoints. AEs were reported in 18 (8.4%) patients in the DA-5204 group and 19 (8.8%) in the DA-9601 group. Rates of AE were not different between the two groups. No serious AE or adverse drug reaction (ADR) occurred. These results demonstrate the non-inferiority of DA-5204 compared to DA-9601. DA-5204 is as effective as DA-9601 in the treatment of erosive gastritis. Registered randomized clinical trial at ClinicalTrials.gov (NCT02282670). © 2017 The Korean Academy of Medical Sciences.

  12. Platelets contribute to postnatal occlusion of the ductus arteriosus.

    PubMed

    Echtler, Katrin; Stark, Konstantin; Lorenz, Michael; Kerstan, Sandra; Walch, Axel; Jennen, Luise; Rudelius, Martina; Seidl, Stefan; Kremmer, Elisabeth; Emambokus, Nikla R; von Bruehl, Marie-Luise; Frampton, Jon; Isermann, Berend; Genzel-Boroviczény, Orsolya; Schreiber, Christian; Mehilli, Julinda; Kastrati, Adnan; Schwaiger, Markus; Shivdasani, Ramesh A; Massberg, Steffen

    2010-01-01

    The ductus arteriosus (DA) is a fetal shunt vessel between the pulmonary artery and the aorta that closes promptly after birth. Failure of postnatal DA closure is a major cause of morbidity and mortality particularly in preterm neonates. The events leading to DA closure are incompletely understood. Here we show that platelets have an essential role in DA closure. Using intravital microscopy of neonatal mice, we observed that platelets are recruited to the luminal aspect of the DA during closure. DA closure is impaired in neonates with malfunctioning platelet adhesion or aggregation or with defective platelet biogenesis. Defective DA closure resulted in a left-to-right shunt with increased pulmonary perfusion, pulmonary vascular remodeling and right ventricular hypertrophy. Our findings indicate that platelets are crucial for DA closure by promoting thrombotic sealing of the constricted DA and by supporting luminal remodeling. A retrospective clinical study revealed that thrombocytopenia is an independent predictor for failure of DA closure in preterm human newborns, indicating that platelets are likely to contribute to DA closure in humans.

  13. Tools to discover anionic and nonionic polyfluorinated alkyl surfactants by liquid chromatography electrospray ionisation mass spectrometry.

    PubMed

    Trier, Xenia; Granby, Kit; Christensen, Jan H

    2011-10-07

    A tiered approach is proposed for the discovery of unknown anionic and nonionic polyfluorinated alkyl surfactants (PFASs) by reversed phase ultra high performance liquid chromatography (UHPLC)--negative electrospray ionisation--quadrupole time of flight mass spectrometry (UHPLC-ESI(-)-QTOF-MS). The chromatographic separation, ionisation and detection of PFASs mixtures, was achieved at high pH (pH=9.7) with NH(4)OH as additive. To distinguish PFASs from other chemicals we used the characteristic negative mass defects of PFASs, their specific losses of 20 Da (HF) and the presence of series of chromatographic peaks, belonging to homologues series with m/z of n×50 Da (CF(2)) or n×100 Da (CF(2)CF(2)). The elemental composition of the precursor ions were deducted from the accurate m/z values of the deprotonated molecules [M-H](-). In case of in-source fragmentation, the presence of dimers, e.g. [M(2)-H](-) and adduct ions such as [M-H+solvent](-) and [(M-H)(M-H+Na)(n)](-) were used to confirm the identity of the precursor ions. In relation to quantification of PFASs, we discuss how their surfactancy influence the ESI processes, challenge their handling in solution and choices of precursor-to-product ions for MSMS of e.g., structural PFAS isomers. The method has been used to discover PFASs in industrial blends and in extracts from food contact materials. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Multicenter Evaluation of Cystatin C Measurement after Assay Standardization.

    PubMed

    Bargnoux, Anne-Sophie; Piéroni, Laurence; Cristol, Jean-Paul; Kuster, Nils; Delanaye, Pierre; Carlier, Marie-Christine; Fellahi, Soraya; Boutten, Anne; Lombard, Christine; González-Antuña, Ana; Delatour, Vincent; Cavalier, Etienne

    2017-04-01

    Since 2010, a certified reference material ERM-DA471/IFCC has been available for cystatin C (CysC). This study aimed to assess the sources of uncertainty in results for clinical samples measured using standardized assays. This evaluation was performed in 2015 and involved 7 clinical laboratories located in France and Belgium. CysC was measured in a panel of 4 serum pools using 8 automated assays and a candidate isotope dilution mass spectrometry reference measurement procedure. Sources of uncertainty (imprecision and bias) were evaluated to calculate the relative expanded combined uncertainty for each CysC assay. Uncertainty was judged against the performance specifications derived from the biological variation model. Only Siemens reagents on the Siemens systems and, to a lesser extent, DiaSys reagents on the Cobas system, provided results that met the minimum performance criterion calculated according to the intraindividual and interindividual biological variations. Although the imprecision was acceptable for almost all assays, an increase in the bias with concentration was observed for Gentian reagents, and unacceptably high biases were observed for Abbott and Roche reagents on their own systems. This comprehensive picture of the market situation since the release of ERM-DA471/IFCC shows that bias remains the major component of the combined uncertainty because of possible problems associated with the implementation of traceability. Although some manufacturers have clearly improved their calibration protocols relative to ERM-DA471, most of them failed to meet the criteria for acceptable CysC measurements. © 2016 American Association for Clinical Chemistry.

  15. Differentiation of Crataegus spp. guided by nuclear magnetic resonance spectrometry with chemometric analyses.

    PubMed

    Lund, Jensen A; Brown, Paula N; Shipley, Paul R

    2017-09-01

    For compliance with US Current Good Manufacturing Practice regulations for dietary supplements, manufacturers must provide identity of source plant material. Despite the popularity of hawthorn as a dietary supplement, relatively little is known about the comparative phytochemistry of different hawthorn species, and in particular North American hawthorns. The combination of NMR spectrometry with chemometric analyses offers an innovative approach to differentiating hawthorn species and exploring the phytochemistry. Two European and two North American species, harvested from a farm trial in late summer 2008, were analyzed by standard 1D 1 H and J-resolved (JRES) experiments. The data were preprocessed and modelled by principal component analysis (PCA). A supervised model was then generated by partial least squares-discriminant analysis (PLS-DA) for classification and evaluated by cross validation. Supervised random forests models were constructed from the dataset to explore the potential of machine learning for identification of unique patterns across species. 1D 1 H NMR data yielded increased differentiation over the JRES data. The random forests results correlated with PLS-DA results and outperformed PLS-DA in classification accuracy. In all of these analyses differentiation of the Crataegus spp. was best achieved by focusing on the NMR spectral region that contains signals unique to plant phenolic compounds. Identification of potentially significant metabolites for differentiation between species was approached using univariate techniques including significance analysis of microarrays and Kruskall-Wallis tests. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Sorption Modeling of Strontium, Plutonium, Uranium and Neptunium Adsorption on Monosodium Titanate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fondeur, F.F.

    2003-10-30

    We examined the ability of various equilibrium isotherms to replicate the available data for the adsorption of strontium (Sr), plutonium (Pu), uranium (U) and neptunium (Np) on monosodium titanate (MST) during the treatment of simulated and actual Savannah River Site high-level waste. The analysis considered 29 isotherm models from the literature. As part of this study, we developed a general method for selecting the best isotherm models. The selection criteria for rating the isotherms considered the relative error in predicting the experimental data, the complexity of the mathematical expressions, the thermodynamic validity of the expressions, and statistical significance for themore » expressions. The Fowler Guggenheim-Jovanovic Freundlich (FG-JF), the Fowler Guggenheim-Langmuir Freundlich (FG-LF) and the Dubinin-Astashov (DA) models each reliably predicted the actinide and strontium adsorption on MST. The first two models describe the adsorption process by single layer formation and later al interactions between adsorbed sorbates while the Dubinin-Astashov model assumes volume filling of micropores (by osmotic pressure difference). These two mechanisms include mutually exclusive assumptions. However, we can not determine which model best represents the various adsorption mechanisms on MST. Based on our analysis, the DA model predicted the data well. The DA model assumes that an initial sorption layer forms after which networking begins in the pore spaces, filling the volume by a second mechanism. If this mechanism occurs in MST, as the experimental data suggests, then we expect all the empty and closed spaces of MST to contain actinides and strontium when saturated. Prior microstructure analyses determined that the MST surface is best described as heterogeneous (i.e., a semi-crystalline outer layer on an amorphous core) or composite material for adsorption. Therefore, we expect the empty spaces (of nanometer size) between the crystalline units in the fibrous material to provide sorption area for the actinides and strontium. Since each of the three models work reliably, we recommend use of the computationally simplest model as the primary tool until future work can differentiate between the two mechanisms. The Dubinin-Astashov model possesses a simpler mathematical form with fewer parameters and operations.« less

  17. An integrative theory of the phasic and tonic modes of dopamine modulation in the prefrontal cortex.

    PubMed

    Dreher, Jean-Claude; Burnod, Yves

    2002-01-01

    This paper presents a model of both tonic and phasic dopamine (DA) effects on maintenance of working memory representations in the prefrontal cortex (PFC). The central hypothesis is that DA modulates the efficacy of inputs to prefrontal pyramidal neurons to prevent interferences for active maintenance. Phasic DA release, due to DA neurons discharges, acts at a short time-scale (a few seconds), while the tonic mode of DA release, independent of DA neurons firing, acts at a long time-scale (a few minutes). The overall effect of DA modulation is modeled as a threshold restricting incoming inputs arriving on PFC neurons. Phasic DA release temporary increases this threshold while tonic DA release progressively increases the basal level of this threshold. Thus, unlike the previous gating theory of phasic DA release, proposing that it facilitates incoming inputs at the time of their arrival, the effect of phasic DA release is supposed to restrict incoming inputs during a period of time after DA neuron discharges. The model links the cellular and behavioral levels during performance of a working memory task. It allows us to understand why a critical range of DA D1 receptors stimulation is required for optimal working memory performance and how D1 receptor agonists (respectively antagonists) increase perseverations (respectively distractability). Finally, the model leads to several testable predictions, including that the PFC regulates DA neurons firing rate to adapt to the delay of the task and that increase in tonic DA release may either improve or decrease performance, depending on the level of DA receptors stimulation at the beginning of the task.

  18. Neurobiological model of stimulated dopamine neurotransmission to interpret fast-scan cyclic voltammetry data.

    PubMed

    Harun, Rashed; Grassi, Christine M; Munoz, Miranda J; Torres, Gonzalo E; Wagner, Amy K

    2015-03-02

    Fast-scan cyclic voltammetry (FSCV) is an electrochemical method that can assess real-time in vivo dopamine (DA) concentration changes to study the kinetics of DA neurotransmission. Electrical stimulation of dopaminergic (DAergic) pathways can elicit FSCV DA responses that largely reflect a balance of DA release and reuptake. Interpretation of these evoked DA responses requires a framework to discern the contribution of DA release and reuptake. The current, widely implemented interpretive framework for doing so is the Michaelis-Menten (M-M) model, which is grounded on two assumptions- (1) DA release rate is constant during stimulation, and (2) DA reuptake occurs through dopamine transporters (DAT) in a manner consistent with M-M enzyme kinetics. Though the M-M model can simulate evoked DA responses that rise convexly, response types that predominate in the ventral striatum, the M-M model cannot simulate dorsal striatal responses that rise concavely. Based on current neurotransmission principles and experimental FSCV data, we developed a novel, quantitative, neurobiological framework to interpret DA responses that assumes DA release decreases exponentially during stimulation and continues post-stimulation at a diminishing rate. Our model also incorporates dynamic M-M kinetics to describe DA reuptake as a process of decreasing reuptake efficiency. We demonstrate that this quantitative, neurobiological model is an extension of the traditional M-M model that can simulate heterogeneous regional DA responses following manipulation of stimulation duration, frequency, and DA pharmacology. The proposed model can advance our interpretive framework for future in vivo FSCV studies examining regional DA kinetics and their alteration by disease and DA pharmacology. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Optogenetic versus electrical stimulation of dopamine terminals in the nucleus accumbens reveals local modulation of presynaptic release

    PubMed Central

    Melchior, James R.; Ferris, Mark J.; Stuber, Garret D.; Riddle, David R.; Jones, Sara R.

    2015-01-01

    The nucleus accumbens is highly heterogeneous, integrating regionally distinct afferent projections and accumbal interneurons, resulting in diverse local microenvironments. Dopamine (DA) neuron terminals similarly express a heterogeneous collection of terminal receptors that modulate DA signaling. Cyclic voltammetry is often used to probe DA terminal dynamics in brain slice preparations; however, this method traditionally requires electrical stimulation to induce DA release. Electrical stimulation excites all of the neuronal processes in the stimulation field, potentially introducing simultaneous, multi-synaptic modulation of DA terminal release. We used optogenetics to selectively stimulate DA terminals and used voltammetry to compare DA responses from electrical and optical stimulation of the same area of tissue around a recording electrode. We found that with multiple pulse stimulation trains, optically stimulated DA release increasingly exceeded that of electrical stimulation. Furthermore, electrical stimulation produced inhibition of DA release across longer duration stimulations. The GABAB antagonist, CGP 55845, increased electrically stimulated DA release significantly more than light stimulated release. The nicotinic acetylcholine receptor antagonist, dihydro-β-erythroidine hydrobromide, inhibited single pulse electrically stimulated DA release while having no effect on optically stimulated DA release. Our results demonstrate that electrical stimulation introduces local multi-synaptic modulation of DA release that is absent with optogenetically targeted stimulation. PMID:26011081

  20. Structure of a designed protein cage that self-assembles into a highly porous cube

    DOE PAGES

    Lai, Yen-Ting; Reading, Eamonn; Hura, Greg L.; ...

    2014-11-10

    Natural proteins can be versatile building blocks for multimeric, self-assembling structures. Yet, creating protein-based assemblies with specific geometries and chemical properties remains challenging. Highly porous materials represent particularly interesting targets for designed assembly. Here we utilize a strategy of fusing two natural protein oligomers using a continuous alpha-helical linker to design a novel protein that self assembles into a 750 kDa, 225 Å diameter, cube-shaped cage with large openings into a 130 Å diameter inner cavity. A crystal structure of the cage showed atomic level agreement with the designed model, while electron microscopy, native mass spectrometry, and small angle x-raymore » scattering revealed alternate assembly forms in solution. These studies show that accurate design of large porous assemblies with specific shapes is feasible, while further specificity improvements will likely require limiting flexibility to select against alternative forms. Finally, these results provide a foundation for the design of advanced materials with applications in bionanotechnology, nanomedicine and material sciences.« less

  1. The Ubiquitin Receptor DA1 Interacts with the E3 Ubiquitin Ligase DA2 to Regulate Seed and Organ Size in Arabidopsis[C][W

    PubMed Central

    Xia, Tian; Li, Na; Dumenil, Jack; Li, Jie; Kamenski, Andrei; Bevan, Michael W.; Gao, Fan; Li, Yunhai

    2013-01-01

    Seed size in higher plants is determined by the coordinated growth of the embryo, endosperm, and maternal tissue. Several factors that act maternally to regulate seed size have been identified, such as AUXIN RESPONSE FACTOR2, APETALA2, KLUH, and DA1, but the genetic and molecular mechanisms of these factors in seed size control are almost totally unknown. We previously demonstrated that the ubiquitin receptor DA1 acts synergistically with the E3 ubiquitin ligase ENHANCER1 OF DA1 (EOD1)/BIG BROTHER to regulate the final size of seeds in Arabidopsis thaliana. Here, we describe another RING-type protein with E3 ubiquitin ligase activity, encoded by DA2, which regulates seed size by restricting cell proliferation in the maternal integuments of developing seeds. The da2-1 mutant forms large seeds, while overexpression of DA2 decreases seed size of wild-type plants. Overexpression of rice (Oryza sativa) GRAIN WIDTH AND WEIGHT2, a homolog of DA2, restricts seed growth in Arabidopsis. Genetic analyses show that DA2 functions synergistically with DA1 to regulate seed size, but does so independently of EOD1. Further results reveal that DA2 interacts physically with DA1 in vitro and in vivo. Therefore, our findings define the genetic and molecular mechanisms of three ubiquitin-related proteins DA1, DA2, and EOD1 in seed size control and indicate that they are promising targets for crop improvement. PMID:24045020

  2. Identification by GeLC-MS/MS of trypsin inhibitor in sarcoplasmic proteins of three tropical fish and characterization of their inhibitory properties.

    PubMed

    Siriangkanakun, Siriphon; Li-Chan, Eunice C Y; Yongsawadigul, Jirawat

    2014-07-01

    Sarcoplasmic proteins from 3 fish species were fractionated by 50% to 70% ammonium sulfate precipitation. Lyophilized fractionated sarcoplasmic proteins of threadfin bream (TB-SP), bigeye snapper (BS-SP), and yellow croaker (YC-SP) showed 80% to 92% trypsin inhibitory activity. Trypsin inhibitory activity staining gel electrophoresis revealed bands at 32, 33, 37, 45, 48, and 50 kDa for the 3 species, and a band at 95 kDa was observed for TB-SP and YC-SP. Alpha-1-antitrypsin with molecular mass of 45 to 50 kDa was identified in YC-SP by gel-based liquid chromatography-tandem mass spectrometry (GeLC-MS/MS). Other major protein bands appeared on trypsin activity staining included phosphorylase, glyceraldehyde-3-phosphate dehydrogenase, and creatine kinase with molecular mass of 95 and 35 to 40 kDa, respectively. But, these 3 proteins did not show true trypsin inhibitory activity. Trypsin inhibitory activity of fractionated sarcoplasmic proteins showed good stability, with >80% activity retained at 60 °C and up to 0.6 M NaCl. TB-SP showed the highest inhibitory activity against autolysis of washed threadfin bream mince at 65 °C. Addition of 0.5% or 1% TB-SP improved textural properties of threadfin bream surimi gels preincubated at 37 or 65 °C followed by heating at 90 °C. Therefore, TB-SP could be a promising protein ingredient for enhancing surimi gel texture. Threadfin bream, bigeye snapper, and yellow croaker are the main species used as raw material for tropical surimi production. Sarcoplasmic proteins from 3 species contain trypsin inhibitor(s) that can minimize proteolytic activity and improve gel texture of proteinase-laden fish muscle. Therefore, sarcoplasmic proteins that are byproducts from surimi processing of these species could be recovered, fractionated, and utilized as a functional protein ingredient. © 2014 Institute of Food Technologists®

  3. Nanostructured Polyaniline Coating on ITO Glass Promotes the Neurite Outgrowth of PC 12 Cells by Electrical Stimulation.

    PubMed

    Wang, Liping; Huang, Qianwei; Wang, Jin-Ye

    2015-11-10

    A conducting polymer polyaniline (PANI) with nanostructure was synthesized on indium tin oxide (ITO) glass. The effect of electrical stimulation on the proliferation and the length of neurites of PC 12 cells was investigated. The dynamic protein adsorption on PANI and ITO surfaces in a cell culture medium was also compared with and without electrical stimulation. The adsorbed proteins were characterized using SDS-PAGE. A PANI coating on ITO surface was shown with 30-50 nm spherical nanostructure. The number of PC 12 cells was significantly greater on the PANI/ITO surface than on ITO and plate surfaces after cell seeding for 24 and 36 h. This result confirmed that the PANI coating is nontoxic to PC 12 cells. The electrical stimulation for 1, 2, and 4 h significantly enhanced the cell numbers for both PANI and ITO conducting surfaces. Moreover, the application of electrical stimulation also improved the neurite outgrowth of PC 12 cells, and the number of PC 12 cells with longer neurite lengths increased obviously under electrical stimulation for the PANI surface. From the mechanism, the adsorption of DMEM proteins was found to be enhanced by electrical stimulation for both PANI/ITO and ITO surfaces. A new band 2 (around 37 kDa) was observed from the collected adsorbed proteins when PC 12 cells were cultured on these surfaces, and culturing PC 12 cells also seemed to increase the amount of band 1 (around 90 kDa). When immersing PANI/ITO and ITO surfaces in a DMEM medium without a cell culture, the number of band 3 (around 70 kDa) and band 4 (around 45 kDa) proteins decreased compared to that of PC 12 cell cultured surfaces. These results are valuable for the design and improvement of the material performance for neural regeneration.

  4. How Implementation of TQM and the Development of a Process Improvement Model, Within a Forward Support Battalion, Can Improve Preparation of the Material Condition Status Report (DA Form 2406)

    DTIC Science & Technology

    1990-12-01

    studies for the continuing education of managers new to the TQM approach , for informing vendors of their responsibilities under a changed process, and...Department of Defense (DoD) is adopting a management approach known as Total Quality Management (TQM) in an effort to improve quality and productivity...individuals selected be highly knowledgeable about the operations in their shop or unit. The main function of PATs is to collect and summarize process data for

  5. OPERATION CROSSROADS. Test of Target Airplane, Model TBM-3E, Serial Number 69169

    DTIC Science & Technology

    1950-04-25

    Water Absorption. XIX Plastic Test Results - Specific Gravity . XX Port Tire Tent Results. XXI Inner Tube Test Results. XXI Self-Sealing Fuel Cell...prev4ously run on non-radioactive meterials . (b) Tht report describes the daTge suffered by c3rtain materials, and the points of failure and the non...conlucted on 1I tEin’. 1j and b in accnrd:ýtnce thith ~i~ethcd 70,31 of S&ecificuitir~n Li-Ga (14) Sjeiific Gravity - Tests were conducted on Yeter~l,,ls

  6. Limb replantation with two robots: a feasibility study in a pig model.

    PubMed

    Taleb, Chihab; Nectoux, Eric; Liverneaux, Philippe

    2009-01-01

    The aim of this study is to assess the feasibility of limb replantations and transplantations by telesurgery. The material consisted in a large white pig and two surgical robots (DaVinciS telemanipulators). The procedure consisted in a trans-humeral cross-section of the left thoracic limb, which was secondarily replanted. Results showed good vascular permeability, while the operator's physiological tremor was suppressed. Our results seem to demonstrate that telesurgery could improve limb replantation and transplantation management, especially regarding operating gesture precision. (c) 2009 Wiley-Liss, Inc.

  7. Proceedings of US-Latin American Workshop on Molecular and Materials Sciences: Theoretical and Computational Aspects Held in Gainesville, Florida on 10-12 March 1993

    DTIC Science & Technology

    1994-08-09

    City Josd Rdamier and R. Iterative Bogoliubov Transformations and Applications Jauregui Inst. de Fisica , Cuernavaca, Meiico Peter J. Reynolds Quantum...University, Provo, UT 84602 J. R•camier Instituto de Fisica , UNAM, Cuernavaca, Mor., MWxico Gamow states are solutions to the Schr6dinger equation with a...Coutinho Departamento de FAsica do UFPE 50732-910 Recife, PE, Brazil and Jnstituto de Fisica da USP, Czp 20516 01498-970 Sdo Paulo, SP, Brasil The

  8. Effects of omeprazole or cola beverage on the pharmacokinetics of oral DA-8159, a new erectogenic, in rats.

    PubMed

    Lee, Joo H; Bae, Soo K; Kwon, Jong W; Kim, Won B; Lee, Myung G

    2005-12-01

    The changes in pharmacokinetics of DA-8159 by omeprazole with respect to inhibition of CYP3A1/2 in rats were evaluated. After oral administration of DA-8159 at dose of 30 mg/kg to rats pretreated with oral omeprazole at 30 mg/kg for 1 week, the total area under the plasma concentration-time curve from time zero to time infinity (AUC) of DA-8159 was significantly greater (37.5% increase) than that in control rats. This could be due to inhibition of metabolism of DA-8159 by inhibition of CYP3A1/2 by omeprazole. The AUC(DA-8164 (a metabolite of DA-8159))/AUC(DA-8159) ratio was also smaller (32.4% decrease) with omeprazole. After oral administration of DA-8159 at a dose of 30 mg/kg to rats without or with cola beverage, the pharmacokinetic parameters of DA-8159 and DA-8164 were not significantly different between two groups of rats. This suggested that cola beverage did not have any considerable effects on CYP3A1/2 in rats.

  9. 75 FR 75868 - Airworthiness Directives; Diamond Aircraft Industries GmbH Models DA 40 and DA 40F Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... Airworthiness Directives; Diamond Aircraft Industries GmbH Models DA 40 and DA 40F Airplanes AGENCY: Federal... of the Thielert Engine Owners Group commented that the Model DA 42 has the same door design and the same unsafe condition. He recommended that the AD also apply to the Model DA 42. The FAA has discussed...

  10. Characterization of low molecular weight fragments from gamma irradiated κ-carrageenan used as plant growth promoter

    NASA Astrophysics Data System (ADS)

    Abad, Lucille V.; Aurigue, Fernando B.; Relleve, Lorna S.; Montefalcon, Djowel Recto V.; Lopez, Girlie Eunice P.

    2016-01-01

    Radiation degraded κ-carrageenan (1% solution at absorbed doses of 20 kGy and 30 kGy) were tested for its plant growth promoter (PGP) effect on pechay plants under hydroponics condition. Results revealed that higher PGP effects were found in κ-carrageenan irradiated at an absorbed dose of 30 kGy. Mw of irradiated κ-carrageenan as measured by GPC were determined to be 7362 Da and 6762 Da for 20 kGy and 30 kGy, respectively. Fractionation of the irradiated κ-carrageenan (30 kGy) was done to separate different Mw fractions using Mw cut-off filters of 1 kDa, 3 kDa, and 5 kDa. The PGP effect of the different retentates showed that biological activity in plants followed the order of 5 kDa>3 kDa>1 kDa using hydroponics condition but the reverse was observed in the order of 1 kDa>3 kDa>5 kDa when absorbed in plants by foliar spraying. GPC chromatogram indicated at least three (3) low molecular weight (LMW) fragments from radiation modified κ-carrageenan solution with an Mw<2000 Da. A fragment has also been identified with an Mw of as low as 160 Da which was produced under acidic (un-neutralized) condition. This may be attributed to the formation of 5-hydroxymethylfurfural (5-HMF).

  11. The role of N-methyl-D-aspartate receptors and nitric oxide in cochlear dopamine release.

    PubMed

    Halmos, G; Horváth, T; Polony, G; Fekete, A; Kittel, A; Vizi, E S; van der Laan, B F A M; Zelles, T; Lendvai, B

    2008-06-23

    Dopamine (DA) released from lateral olivocochlear (LOC) terminals may have a neuroprotective effect in the cochlea. To explore the role of N-methyl-d-aspartate (NMDA) receptors and nitric oxide (NO) in the modulation of a cochlear DA release, we measured the release of [3H]DA from isolated mouse cochlea in response to the application of NMDA. NMDA at 100 muM significantly increased the electrical-field stimulation-evoked and resting release of DA from the cochlea. The NO donor sodium nitroprusside enhanced the basal outflow of DA but failed to influence the evoked release. The administration of the nitric oxide synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) alone was ineffective, but it significantly inhibited the initial phase of the NMDA-induced elevation of DA outflow, which suggested the role of NO in the NMDA-induced DA release. The DA uptake inhibitor nomifensine increased the electrically evoked release of DA. Nomifensine failed to change the effect of NMDA on the resting or electrically-evoked DA release, which suggested that the uptake mechanism does not play a role in NMDA-evoked and NO-mediated DA release. In summary, we provide evidence that NO can modulate the release of DA from the cochlea following NMDA receptor activation, but does not affect the uptake of DA.

  12. Molecular bulk heterojunctions: an emerging approach to organic solar cells.

    PubMed

    Roncali, Jean

    2009-11-17

    The predicted exhaustion of fossil energy resources and the pressure of environmental constraints are stimulating an intensification of research on renewable energy sources, in particular, on the photovoltaic conversion of solar energy. In this context, organic solar cells are attracting increasing interest that is motivated by the possibility of fabricating large-area, lightweight, and flexible devices using simple techniques with low environmental impact. Organic solar cells are based on a heterojunction resulting from the contact of a donor (D) and an acceptor (A) material. Absorption of solar photons creates excitons, Coulombically bound electron-hole pairs, which diffuse to the D/A interface, where they are dissociated into free holes and electrons by the electric field. D/A heterojunctions can be created with two types of architectures, namely, bilayer heterojunction and bulk heterojunction (BHJ) solar cells. BHJ cells combine the advantages of easier fabrication and higher conversion efficiency due to the considerably extended D/A interface. Until now, the development of BHJ solar cells has been essentially based on the use of soluble pi-conjugated polymers as donor material. Intensive interdisciplinary research carried out in the past 10 years has led to an increase in the conversion efficiency of BHJ cells from 0.10 to more than 5.0%. These investigations have progressively established regioregular poly(3-hexylthiophene) (P3HT) as the standard donor material for BHJ solar cells, owing to a useful combination of optical and charge-transport properties. However, besides the limit imposed to the maximum conversion efficiency by its intrinsic electronic properties, P3HT and more generally polymers pose several problems related to the control of their structure, molecular weight, polydispersity, and purification. In this context, recent years have seen the emergence of an alternative approach based on the replacement of polydisperse polymers by soluble, conjugated single molecules as donor materials in BHJ cells. In fact, molecular donors present specific advantages in terms of structural definition, synthesis, and purification. In this Account, we present a brief survey of recent work in this nascent field of new single-molecule donors in organic solar cells. Various series of three-dimensional donors built by the attachment of different kinds of conjugated branches on a central node, including silicon, twisted bithiophene, triphenylamine, and borondipyrromethene (BODIPY), are discussed in relation to the performances of the resulting solar cells. Furthermore, it is shown that the concept of a molecular donor with internal charge transfer leads at the same time to improved light-harvesting properties, red-shifted photoresponse, and a higher open-circuit voltage, resulting in a considerable increase of conversion efficiency, up to values now approaching 3%. These results show that soluble molecular donors can lead to BHJ cells that combine high conversion efficiency with the distinct advantages of working with single molecules, including structural definition, synthesis, purification, and reproducibility.

  13. Metaproteomics of Microbiota in Naturally Fermented Soybean Paste, Da-jiang.

    PubMed

    Zhang, Ping; Zhang, Pengfei; Xie, Mengxi; An, Feiyu; Qiu, Boshu; Wu, Rina

    2018-05-01

    Da-jiang is a typical traditional fermented soybean product in China. At present, the proteins in da-jiang are needed to be explored. The composition and species of microbial proteins in traditional fermented da-jiang were analyzed by metaproteomics based on sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE) and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). The results showed that the number and variety of microbial proteins in the traditional fermented da-jiang from different regions were different. The production site influences the fermentation in da-jiang. Then we analyzed the functions of the microbial proteins identified in da-jiang, and found that they were mainly involved in the process of protein synthesis, glycometabolism and nucleic acid synthesis. In addtion, we compared the proteins composition in different da-jiang. There are 51 common proteins of naturally fermented da-jiang, and 25 common microbial sources. The main commonly microbial sources of fungal proteins are Saccharomyces cerevisiae and Schizosaccharomyces; the main commonly microbial sources of bacterial proteins are Enterococcus faecalis, Leuconostoc mesenteroides, Acinetobacter baumannii, and Bacillus subtilis. These common microbes play the predominant role in da-jiang fermentation. The present results help us to understand the fermentation of da-jiang and improve the quality and safety of final products in the future. The study illustrated metaproteome of microbiota in traditional fermented soybean paste, da-jiang, by sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE) and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). A method of extracting metaproteome from microbiota in da-jiang was attempted. The findings help to understand the fermentation of da-jiang and improve the quality and safety of da-jiang in fermented industry. © 2018 Institute of Food Technologists®.

  14. Identification of proteinaceous material in the bone of the dinosaur Iguanodon.

    PubMed

    Embery, Graham; Milner, Angela C; Waddington, Rachel J; Hall, Rachel C; Langley, Martin S; Milan, Anna M

    2003-01-01

    This study has directed attention at the search for bone-related proteins in an extract of demineralized rib bone of the 120 mya Iguanodon. The inner compact bone was demineralized and the GuCl extract resolved into 11 fractions using anion exchange chromatography, which all contained silver-reactive proteins with various amino acid profiles. Two specific fractions, iv and xi, revealed characteristics typical of contemporary phosphoproteins and proteoglycans, respectively. Fraction iv, 43-57 kDa, contained a high ratio of aspartate and serine, although no phosphate was discernable. Fraction xi contained a band of 41-47 kDa and was rich in chondroitin sulphate and hyaluronan. In addition an early eluting fraction was immunoreactive with an antibody against osteocalcin. A cancellous bone fraction from the same bone sample was also analyzed using N-terminal sequencing and revealed potential similarities with cystatin. While we do not claim to have identified the presence of intact proteins, this study has value in demonstrating that extruded extracellular matrix is protected by its capacity to induce mineralization, which subsequently is important in conserving detectable protein products in ancient skeletal tissues.

  15. Dry entrapment of enzymes by epoxy or polyester resins hardened on different solid supports.

    PubMed

    Barig, Susann; Funke, Andreas; Merseburg, Andrea; Schnitzlein, Klaus; Stahmann, K-Peter

    2014-06-10

    Embedding of enzymes was performed with epoxy or polyester resin by mixing in a dried enzyme preparation before polymerization was started. This fast and low-cost immobilization method produced enzymatically active layers on different solid supports. As model enzymes the well-characterized Thermomyces lanuginosus lipase and a new threonine aldolase from Ashbya gossypii were used. It was shown that T. lanuginosus lipase recombinantly expressed in Aspergillus oryzae is a monomeric enzyme with a molecular mass of 34kDa, while A. gossypii threonine aldolase expressed in Escherichia coli is a pyridoxal-5'-phosphate binding homotetramer with a mass of 180kDa. The enzymes were used freeze dried, in four different preparations: freely diffusing, adsorbed on octyl sepharose, as well as cross-linked enzyme aggregates or as suspensions in organic solvent. They were mixed with standard two-component resins and prepared as layers on solid supports made of different materials e.g. metal, glass, polyester. Polymerization led to encapsulated enzyme preparations showing activities comparable to literature values. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Layer-by-layer composite film of nickel phthalocyanine and montmorillonite clay for synergistic effect on electrochemical detection of dopamine

    NASA Astrophysics Data System (ADS)

    de Lucena, Nathalia C.; Miyazaki, Celina M.; Shimizu, Flávio M.; Constantino, Carlos J. L.; Ferreira, Marystela

    2018-04-01

    Dopamine (DA) abnormal levels are related to diseases which makes important the development of fast, reliable, low-cost and sensitive devices for diagnosis and pharmaceutical controls. Nanostructured film composite of sodium montmorillonite clay (Na+MMT) and nickel phthalocyanine (NiTsPc) was self-assembled by layer-by-layer (LbL) technique and applied as electrochemical sensor for DA in the presence of common natural interferents as ascorbic acid (AA) and uric acid (UA). Three different LbL architecture films were investigated: LbL films of clay (PEI/Na+MMT) and phthalocyanine (PEI/NiTsPc) in a bilayer structure with a conventional polyelectrolyte (PEI) and a composite film formed by both materials to verify the synergistic effect in the LbL film in a quadri-layer assembly (PEI/Na+MMT/PEI/NiTsPc). Structural characterization indicated molecular level interactions between the layers forming the LbL films. The ITO/(PEI/Na+MMT/PEI/NiTsPc)10 electrode exhibited a LOD of 1.0 μmol L-1 and linear range 5-150 μmol L-1.

  17. Lignin preparation from oil palm empty fruit bunches by sequential acid/alkaline treatment--A biorefinery approach.

    PubMed

    Medina, Jesus David Coral; Woiciechowski, Adenise; Zandona Filho, Arion; Noseda, Miguel D; Kaur, Brar Satinder; Soccol, Carlos Ricardo

    2015-10-01

    Lignin is an important raw material for the sustainable biorefineries and also the forerunner of high-value added products, such as biocomposite for chemical, pharmaceutical and cement industries. Oil palm empty fruit bunches (OPEFB) were used for lignin preparation by successive treatment with 1% (w/w) H2SO4 at 121°C for 60 min and 2.5% NaOH at 121°C for 80 min resulting in the high lignin yield of 28.89%, corresponding to 68.82% of the original lignin. The lignin obtained was characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The results indicated a lignin with molecular masses ramping from 4500 kDa to 12,580 kDa. FTIR and NMR of these lignins showed more syringyl and p-hydroxyphenyl than guaiacyl units. Moderate acid/alkaline treatment provided lignin with high industrial potential and acid hydrolyzates rich in fermentable sugars and highly porous cellulosic fibers. Copyright © 2015. Published by Elsevier Ltd.

  18. Assessment of the discrimination of animal fat by FT-Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Abbas, O.; Fernández Pierna, J. A.; Codony, R.; von Holst, C.; Baeten, V.

    2009-04-01

    In recent years, there has been an increased attention towards the composition of feeding fats. In the aftermath of the BSE crisis all animal by-products utilised in animal nutrition have been subjected to close scrutiny. Regulation requires that the material belongs to the category of animal by-products fit for human consumption. This implies the use of reliable techniques in order to insure the safety of products. The feasibility of using rapid and non-destructive methods, to control the composition of feedstuffs on animal fats has been studied. Fourier Transform Raman spectroscopy has been chosen for its advantage to give detailed structural information. Data were treated using chemometric methods as PCA and PLS-DA which have permitted to separate well the different classes of animal fats. The same methodology was applied on fats from various types of feedstock and production technology processes. PLS-DA model for the discrimination of animal fats from the other categories presents a sensitivity and a specificity of 0.958 and 0.914, respectively. These results encourage the use of FT-Raman spectroscopy to discriminate animal fats.

  19. The Pharmacokinetics and Biodistribution of a 64 kDa PolyPEG Star Polymer After Subcutaneous and Pulmonary Administration to Rats.

    PubMed

    Khor, Song Yang; Hu, Jinming; McLeod, Victoria M; Quinn, John F; Porter, Christopher J H; Whittaker, Michael R; Kaminskas, Lisa M; Davis, Thomas P

    2016-01-01

    PolyPEG star polymers have potential utility as cost-effective polymeric drug delivery vehicles, and as such, it is important to develop an understanding of their biopharmaceutical behavior. Moreover, although a number of studies have evaluated the utility of PolyPEG stars in vitro, investigation of these novel materials in vivo has been limited. Herein, we evaluated the pharmacokinetics of a 64 kDa tritiated PEG-based star polymer after subcutaneous and pulmonary administration in rats. After subcutaneous administration, the star polymer showed near complete bioavailability (∼80%) and a similar organ biodistribution profile to the polymer after intravenous administration. After intratracheal instillation to the lungs, the star polymer showed limited bioavailability (∼3%), and most of the administered radiolabel was recovered in lung tissue and feces after 6 d. The data reported here suggest that star polymers display similar pharmaceutical behavior to PEGylated dendrimers after subcutaneous and inhaled delivery and may therefore be used as similar, but more cost-effective drug delivery vehicles. Copyright © 2016. Published by Elsevier Inc.

  20. Energy transfer mechanism and optoelectronic properties of (PFO/TiO2)/Fluorol 7GA nanocomposite thin films

    NASA Astrophysics Data System (ADS)

    Al-Asbahi, Bandar Ali

    2017-10-01

    Energy transfer between poly (9,9'-di-n-octylfluorenyl-2,7-diyl) (PFO) as a donor in presence of TiO2 nanoparticles (NPs) and Fluorol 7GA as an acceptor with different weight ratios has been investigated by steady-state emission measurements. Based on the absorption and fluorescence measurements, the energy transfer properties, such as quenching rate constant (kSV), energy transfer rate constant (kET), quantum yield (ϕDA), and lifetime (τDA), of the donor in the presence of the acceptor, energy transfer probability (PDA), energy transfer efficiency (η), energy transfer time (τET), and critical distance of the energy transfer (Ro) were calculated. Förster-type energy transfer between the excited donor and ground-state acceptor molecules was the dominant mechanism responsible for the energy transfer as evidenced by large values of kSV, kET, and Ro. Moreover, these composite materials were employed as an emissive layer in organic light-emitting diodes (OLEDs). Additionally, the optoelectronic properties of OLEDs were investigated in terms of current density-voltage characteristics and electroluminescence spectra.

Some links on this page may take you to non-federal websites. Their policies may differ from this site.
Top