Sample records for laser emitindo em
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Energy Technology Data Exchange (ETDEWEB)
Rezende, Sandra Bastos
2001-07-01
In this research, it was analyzed the acceleration of the healing process of cutaneous lesions in mice, using a diode laser emitting in 830 nm. The 64 selected animals in this study were randomically divided into four groups of 16 animals each (G1, G2, G3 and G4). Biometric and histological comparisons were accomplished in the following periods: 3, 7 and 14 days after the surgery and laser application. Three laser irradiation configurations were used: a punctual contact (G2) and two non-contact and uniform (G3 and G4). For group G2, the laser intensity was 428 mW/cm{sup 2} , and for groups G3 and G4 it was 53 mW/cm{sup 2}. The total doses were D = 3 J/cm{sup 2} for groups G2 and G4, and D = 1,3 J/cm{sup 2} for G3. The first group, G1, was considered control and thus not submitted to any treatment after the surgery. All irradiated lesions presented acceleration of the healing process with regard to the control group. However, our results clearly indicate that the smaller laser intensity (uniform irradiation) leaded to the best results. On the other hand, the smaller used dose also leaded to the more significant and expressive results. The combination of the intensity value of 53 mW/cm{sup 2} and the dose of 1,3 J/cm{sup 2} leaded to optimal results, regarding the Biometric and histological analysis, presenting faster lesion contraction, quicker neoformation of epithelial and conjunctive tissue (with more collagen fibers ). (author)
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Uso do laser infravermelho em episiotomia: ensaio clínico aleatorizado
Marina Barreto Alvarenga
2012-01-01
Introdução: A episiotomia é uma ampliação cirúrgica do períneo amplamente utilizada na assistência ao parto, embora seu emprego rotineiro não seja justificado pelas evidências científicas. Está associada à dor e ao desconforto no período pós-parto. O Laser em Baixa Intensidade (LBI) vem se destacando na literatura como uma tecnologia promissora em relação ao tratamento de feridas. Apresenta efeitos de redução da dor, inflamação e estímulo à cicatrização. Objetivo: Avaliar os efeitos do laser ...
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Directory of Open Access Journals (Sweden)
Suziellen Cristina Tenani
2010-06-01
Full Text Available Utilizaram-se 30 corações de capivara (Hydrochoerus hydrochoeris, entre machos fêmeas de diferentes faixas etárias, cedidos pela Empresa Pró-Fauna, cidade de Iguape, estado de São Paulo, registrado no IBAMA sob nº 235930848-0 e no SIF sob nº 3381. As artérias coronárias direita e esquerda foram canuladas e injetadas com substância látex corada com pigmento específico. Em 96,9%s dos corações estudados, encontrou-se as artérias coronária direita e esquerda que possuem origem a partir da aorta ascendente. Em 3,3% dos casos não há artéria coronária esquerda, mas sim os ramos interventricular paraconal e circunflexo. Quanto ao ramo intermédio, este pode apresentar origem a partir do ramo interventricular paraconal em 40% dos casos, ou pode apresentar sua origem diretamente da aorta ascendente em 3,3% dos casos; e, ainda, pode ter origem a partir do ramo circunflexo em 56,6% dos casos. Quanto à artéria coronária direita, esta possui menor calibre que a artéria coronária esquerda em 100% dos casos. Apresenta-se percorrendo o sulco coronário emitindo ramos para a margem ventricular direita. Na face atrial, a referida artéria coronária apresenta ramo anastomótico, em todos os casos, como descrito anteriormente.
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Kelly Cristina Borges Tacon
2011-10-01
Full Text Available PURPOSE: To evaluate the effect the healing activity of diode laser Indium Gallium Aluminum Phosphorus (InGaAlP ë660nm on healing of surgical wounds in rats. METHODS: Fifty-four female Wistar rats were used, divided into three groups (n=18 and subdivided into three subgroups (n=6 to be studied in 5, 10 and 15th days after surgical procedures. The wound was induced in the dorsal-cervical using punch. The lesions were irradiated on alternate days with InGaAlP laser, the energy densities of 3J/cm² (L3 or 6J/cm² (L6. The control group received no irradiation. At 5, 10 and 15th days after surgery the animals were euthanized and the repair area was removed and histological sections were stained with hematoxylin-eosin and picrossírius. We evaluated macroscopic and histological lesions in the times cited, as well as morphometric analysis of angiogenesis and collagen content. RESULTS: The wound healing activity InGaAlP laser was evidenced by increased angiogenesis group L3 and L6 in relation to control group (CG at the 5th day (p=0.0001 and decreased polymorphonuclear infiltrate and hemorrhage (p=0.045 and p=0.07 respectively in the groups L3 and L6 in relation to control group (GC. On the 10 and 15th days was also observed in groups treated with laser L3 and L6 stimulation was pronounced fibroplasia (p=0.0003 and p=0.034 respectively when compared with the control group (CG. CONCLUSION: The InGaAlP laser acted positively on the healing of skin wounds in rats.OBJETIVO: Avaliar a atividade cicatrizante do laser diodo Alumínio Gálio Índio Fósforo (AlGaInP, ë660nm em feridas cutâneas induzida em ratos. MÉTODOS: Foram utilizados 54 ratos Wistar, fêmeas, divididos em três grupos (n=18 e subdivididos em três subgrupos (n=6 animais para serem estudados no 5, 10 e 15º dias após o procedimento cirúrgico. A ferida foi induzida em região dorso-cervical utilizando punch. As lesões foram irradiadas em dias alternados com laser AlGaInP, nas
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Diego Rodrigues Pessoa
2017-12-01
Full Text Available Tendinopatia é o termo utilizado para descrever lesões que afetam os tendões (tendinites e tendinoses, caracterizada pela presença de inflamação e degeneração tecidual, associada à sobrecarga mecânica e a movimentos repetitivos. Diversas modalidades terapêuticas têm sido estudadas no tratamento das tendinopatias, entre elas, destaca-se a terapia a laser de baixa intensidade (TLBI que visa acelerar o processo regenerativo, diminuir a inflamação e reduzir a dor. Diante do exposto, este trabalho teve como objetivo realizar revisão de literatura, de artigos científicos com foco nos efeitos da terapia a laser de baixa intensidade (TLBI, em modelo experimental de tendinopatia em ratos. O estudo baseou-se na investigação de publicações entre janeiro de 2011 a outubro de 2016, em bases de dados eletrônicas com o emprego dos descritores “tendinopatia”, “laserterapia”, “ratos”, “tendão” e “terapia a laser de baixa intensidade”, combinados aos descritores booleanos. Foram selecionados sete artigos que apontam que a TLBI possibilitou a redução de importantes marcadores pró-inflamatórios, tais como IL-6 e TNF-α, bem como a proliferação aumentada de tenócitos, independentemente da dosagem aplicada. Os estudos científicos selecionados nesta revisão sistemática sinalizaram efeitos positivos da TLBI, principalmente na modulação da resposta inflamatória aguda ou crônica após a indução da tendinopatia.
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Tecnologia da informação e comunicação na formação docente em Saúde: relato de experiência
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Silvia Itzcovici Abensur
Full Text Available Com o objetivo de desenvolver diversos olhares e possibilidades sobre ensino e aprendizagem na formação de pós-graduandos para a docência na Faculdade de Medicina da Universidade de São Paulo, em 2001 foi introduzida uma atividade de tecnologia de informação e comunicação. Esta atividade constitui uma oportunidade para os pós-graduandos aplicarem alguns recursos de informática e conhecerem o benefício da multidisciplinaridade, além de demonstrarem suas habilidades de criatividade e planejamento ao desenvolverem uma aula virtual. Ao final, os pós-graduandos avaliam a atividade com relação às características mais importantes e às dificuldades encontradas, emitindo comentários e sugestões. O objetivo deste trabalho é avaliar e relatar a experiência no período de 2006 a 2009, considerando-se as avaliações discentes (167 e os trabalhos desenvolvidos (193.
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DEFF Research Database (Denmark)
Johansen, Tom Keinicke; Krozer, Viktor; Kazmierski, C.
2009-01-01
An improved electromagnetic simulation (EM) based approach has been developed for optimization of the electrical to optical (E/O) transmission properties of integrated electro-absorption modulated lasers (EMLs) aiming at 100 Gbit/s Ethernet applications. Our approach allows for an accurate analysis...... of the EML performance in a hybrid microstrip assembly. The established EM-based approach provides a design methodology for the future hybrid integration of the EML with its driving electronics....
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Rodrigo Paschoal Prado
2006-08-01
Full Text Available PURPOSE: To develop an experimental model to be used in the study of low level Laser therapy on viability of random skin flap in rats. METHODS: The sample was 24 Wistar-EPM rats. The random skin flap measured 10 x 4 cm and a plastic sheet was interposed between the flap and donor site. Group 1 (control underwent sham irradiation with diode laser (830 nm. Group 2 was submitted to laser irradiation with diode laser (830 nm. The animals were submitted to Laser therapy with 36 J/cm² energy density (72 seconds immediately after the surgery and on the four subsequent days. The probe was usually held in contact with the skin flap surface on a point at 2.5 cm cranial from the flap base. On the seventh postoperative day, the percentage of necrotic area was measured and calculated. RESULTS: Group 1 reached an average necrotic area of 48.86%, Group 2 - 23.14%. After the statistic analysis, compared with the control group, Group 2 showed a statistically significant increase in survival area (pOBJETIVO: Propor o desenvolvimento de um modelo experimental para verificar o efeito da laserterapia de baixa intensidade na viabilidade do retalho cutâneo randômico em ratos. MÉTODOS: A amostra constituiu-se de 24 ratos, da linhagem Wistar-EPM. O retalho cutâneo randômico foi realizado com dimensões de 10x4 cm e uma barreira plástica foi interposta entre o mesmo e o leito doador. O Grupo 1 (controle, foi submetido a uma simulação de tratamento com a irradiação laser de diodo (830 nm. O Grupo 2 foi submetido à irradiação laser de diodo (830 nm. Os animais foram submetidos a terapia a laser com densidade de energia de 36 J/cm2 (72 segundos imediatamente após a operação e nos outros quatros dias subseqüentes. A caneta do laser foi posicionada a 90 graus em contato com o retalho cutâneo em um ponto a 2,5 cm da base cranial do retalho. No sétimo dia pós-operatório foram calculadas as porcentagens da área de necrose. RESULTADOS: O Grupo 1 apresentou
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Fernanda de Oliveira Busarello
2011-12-01
Full Text Available O comprometimento do sistema imune, que pode ser apresentado por indivíduos com doenças crônicas, leva à baixa resposta imunológica. Um dos tratamentos utilizados para lesões agudas em tendões é o laser de baixa potência, contudo há uma lacuna em relação ao seu uso em imunodepressão. O objetivo do presente estudo foi analisar se o laser de baixa potência é eficaz para o tratamento da dor em ratos imunodeprimidos submetidos a trauma tendíneo. Foram utilizados 23 ratos, machos, da linhagem Wistar, divididos aleatoriamente em três grupos: grupo controle, placebo e laser. Os animais foram imunodeprimidos (por administração de Ciclosporina A e submetidos à lesão no tendão calcâneo direito, com impacto de cerca de 0,40 J. Para o tratamento, utilizou-se laser de baixa potência, 670 nm, 30 mW e dose de 2 J/cm², durante 3 dias. A avaliação da dor foi realizada pelo teste de incapacidade funcional e por filamento de Von Frey digital. Os resultados apresentaram valores significativos para o grupo laser, com diminuição de dor funcional e da dor à pressão na superfície plantar e no local lesionado (tendão calcâneo direito. Portanto, concluiu-se que o laser de baixa potência é eficaz para reduzir a dor em ratos imunodeprimidos submetidos a trauma tendíneo.The commitment of immune system, which may be presented by individuals with chronic diseases, leading to a low immune response. One of the treatments used for acute injuries in tendons is the low-power laser, however there is a gap in relation to its use in immunosuppression. The objective of this study was to analyze if low-level laser therapy is effective for the treatment of pain in immunosuppressed rats subjected to trauma tendon. We used 23 male rats of Wistar strain, divided randomly in three groups: control group, placebo and laser. The animals were immunosuppressed (by administration of Cyclosporin A and underwent right Achilles tendon injury, with impact of about
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Morfometria do encéfalo e formação do circuito arterioso em coelhos Nova Zelândia
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Janaina de Oliveira Portugal
2014-01-01
Full Text Available http://dx.doi.org/10.5007/2175-7925.2014v27n2p147 O objetivo deste artigo é descrever as principais ramificações da artéria basilar, a formação do circuito arterioso, e a morfometria do encéfalo em coelhos adultos de ambos os sexos. Foi realizada canulação da aorta torácica através de incisão lateral, fixação com solução de formaldeído a 10% e preenchimento do sistema arterial com solução de látex corado. Procedeu-se à craniotomia, remoção e morfometria do encéfalo, além de dissecção para a observação das ramificações principais da artéria basilar e da formação do circuito arterioso. A média e erro padrão do comprimento da artéria basilar foram de 1,293 cm ± 0,024 nas fêmeas e 1,227 cm ± 0,025 nos machos. Em todos os coelhos dissecados, a artéria basilar se originou da anastomose das artérias vertebrais, direita e esquerda, emitindo a artéria cerebelar caudal, ramos variados para bulbo e ponte, ramos terminais e artérias cerebelares rostrais. As artérias da base do encéfalo estiveram na dependência dos sistemas carótico e vértebro-basilar. O circuito arterioso do cérebro estava fechado rostralmente em 10 machos e 12 fêmeas e fechado caudalmente em todos os animais dissecados.
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Fotocoagulação a laser em pacientes portadores de descolamento de retina regmatogênico periférico
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Paulo Escarião
2013-08-01
Full Text Available OBJETIVO: Relatar uma série de casos de descolamento de retina sem envolvimento macular tratados com fotocoagulação a laser. MÉTODOS: Estudo tipo série de casos envolvendo 14 olhos de 12 pacientes com descolamento de retina regmatogênico sem envolvimento macular, retrospectivo, de intervenção. Olhos com procedimentos cirúrgicos prévios foram excluídos. A fotocoagulação a laser foi aplicada com três fileiras confluentes de spot de 300μm, posterior ao descolamento de retina, se extendendo até a ora serrata. A melhor acuidade visual corrigida pré e pós-operatória e a progressão do descolamento de retina foram registrados durante o estudo. RESULTADOS: Treze olhos necessitaram de apenas uma sessão de laser para conter o descolamento de retina. Apenas um olho necessitou de intervenção adicional por causa da evolução do descolamento de retina. Miopia foi encontrada em 7 olhos. Todos os pacientes mantiveram acuidade visual corrigida igual ou melhor que 20/30. CONCLUSÃO:Em casos bem selecionados, a fotocoagulação a laser pode ser considerada para o tratamento de descolamento de retina regmatogênico.
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Rosana Marques Silva
2004-02-01
Full Text Available Utilizaram-se 24 gatas gestantes, sem raça definida, doadas para o estudo da vascularização arterial dos cornos uterinos. Em 20 animais, com o intervalo gestacional entre 7 e 9 semanas, a aorta abdominal foi injetada com Látex-Neoprene 650 corado, associado ao Sulfato de Bário 1004. Os animais foram então radiografados, fixados em solução aquosa de formol 10% e dissecados para estudo da distribuição dos vasos arteriais destinados às regiões paraplacentárias e de cintas placentárias. Em 4 animais realizou-se o exame por Ecografia Power Doppler, onde se observou que nas regiões das cintas placentárias o índice de resistência dos vasos apresenta-se menor do que o encontrado ao longo da artéria uterina. Em todas as observações, a artéria uterina é o principal vaso a irrigar os cornos uterinos, emitindo de 2 a 17 ramos, com maior freqüência de 5 a 12 ramos, os quais se distribuem nas regiões paraplacentárias e/ou das cintas placentárias, formando arcadas anastomósticas. Não houve diferenças estatísticas significativas do número de ramos para cada região individualmente, porém a análise das radiografias contrastadas demonstrou haver uma concentração maior de contraste nas regiões das cintas placentárias. A artéria ovárica participa da vascularização arterial da extremidade cranial dos cornos uterinos, onde se anastomosa com ramos da artéria uterina.
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Jonathas Henrique Pereira
2016-03-01
Full Text Available Resumo Distorções em componentes soldados são alterações permanente de forma e dimensões resultantes das deformações plásticas que ocorrem devido as tensões térmicas desenvolvidas durante o processo de soldagem. Em função dos elevados custos para corrigir essas distorções de soldagem, existe grande interesse das indústrias em prever, monitorar e controlar estas distorções. Este trabalho compara as distorções ocorridas durante a soldagem de modelos de anel segmentado em escala reduzida com dois tipos de juntas (“X” e “V” utilizando a metodologia de monitoramento contínuo da evolução das distorções de soldagem com sensores a laser. Para o monitoramento contínuo são utilizados sensores a laser que são apoiados sobre a peça e os feixes foram projetados em um anteparo translúcido colocado em frente ao mesmo. Com a progressão da distorção durante a soldagem os feixes luminosos se movimentam pelo anteparo proporcionalmente a deformações ocorridas na peça. Os deslocamentos dos pontos luminosos refletidos no anteparo são filmados pelo lado oposto do anteparo. A discretização da filmagem permite analisar as deformações ao longo do processo soldagem e determinar a evolução das distorções em função do tempo. Foi confirmado que as soldagens realizadas em juntas em “X” apresentam menores valores de distorções que as juntas em “V”. Os resultados demostram que para os corpos de prova utilizados neste experimento pelo menos 60% da distorção ocorreu após a extinção do arco. Pelos testes experimentais foi possível afirmar que a técnica de monitoramento com sensores a laser é viável para utilizar na indústria e laboratórios de soldagem, porém faz-se necessário otimizar o processamento dos dados obtidos pela filmagem, permitindo um monitoramento instantâneo. A informação sobre a evolução das distorções durante a soldagem será útil para definir e monitorar de forma mais eficiente o
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Lizarelli Rosane de Fátima Zanirato
2002-01-01
Full Text Available A eficiência da ablação com laser através de um regime de picossegundos minimiza a destruição do material adjacente devido à formação de plasma e ataque. Isso previne a geração excessiva de ondas de choque e promove uma considerável diminuição nos efeitos mecânicos. Nesse estudo foi utilizado um laser de Nd:YAG em picossegundo "Q-switched" e "mode-locked" (Antares 76-s, Coherent, Palo Alto, CA, três molares humanos recém-extraídos e foram realizados 15 microcavidades em esmalte e 9 em dentina. Os parâmetros para irradiar o esmalte seguiram uma freqüência fixa de 100 Hz e potência média de 1,3 W; enquanto que para a dentina, a freqüência foi fixa em 15 Hz enquanto que a potência média variou em 800, 700 e 600 mW. O esmalte demonstrou ser mais capaz de dissipar as ondas de choque do que a dentina, uma vez que as trincas originadas nas microcavidades foram mais freqüentes em tecido dentinário, diferentemente do esmalte. Em conclusão, parece que para manter os aspectos de definição de bordas é importante escolher tempos de irradiação mais curtos, quando as potências médias forem mantidas mais altas, ou seja, energia total entregue mais baixa e bem localizada.
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Vera Christina Waller de Lima
2003-08-01
Full Text Available OBJETIVO: Relatar experiência de longo prazo com ciclofotocoagulação com laser diodo em glaucomas refratários. MÉTODOS: Foram selecionados casos de glaucomas refratários com indicação de ciclofotocoagulação com laser diodo acoplado a uma sonda G (Iris Medical. Todos os procedimentos foram realizados pelo mesmo cirurgião que realizou 20 aplicações (em média com 2000 mW de potência em 270 graus de extensão, com a sonda colocada a 1,5 mm do limbo, por 2,0 a 2,5 s. Foram incluídos somente casos com pelo menos 6 meses de seguimento. Considerou-se sucesso cirúrgico Po final PURPOSE: To report long-term experience with cyclophotocoagulation using diode laser in refractory glaucomas. METHODS: We selected cases of refractory glaucoma with indication for cyclophotocoagulation (CPC with diode laser using a G probe (Iris Medical. All procedures were performed by the same surgeon: twenty applications of 2000 mW power at 270- degree extension. The probe placed set at 1.5 mm from the limbus during 2.0 a 2.5 s. Only cases with at least 6 months of follow-up were included. The procedure was considered successful when IOP was < 24 mmHg or decrease was larger or equal to 30% of the initial IOP with remission of symptoms. Only 25 patients (18.75% concluded the study (36 months. RESULTS: One hundred and thirty cases had a mean follow-up of 18,1 ± 9,6 months with 116 (87.2% successful cases and 17 (12,7% insuccess ful cases. Initial and final IOP were, 48.20 ± 12.11mmHg and 19.93 ± 11,93mmHg respectively (p < 0.0001. Main complications were: "Phthisis bulbi" in 7 (5.2% cases and long-term hypotony in 6 (4.5% cases. CONCLUSIONS: Considering the severity of our cases, we conclude that the long-term results of cyclophotocoagulation with diode laser for refractory glaucomas were satisfactory, with an acceptable incidence of complications.
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Shadia Muhammad Ihlaseh
2007-02-01
Full Text Available INTRODUÇÃO: Microdissecção e captura a laser (MCL é uma técnica de desenvolvimento recente que permite a coleta de células individuais ou pequeno conjunto de células para análise molecular. Atualmente, no Brasil, há raros microscópios para MCL, de modo que a divulgação dos procedimentos inerentes a essa técnica é oportuna para destacar seu amplo potencial para diagnóstico e investigação. OBJETIVO: Este trabalho descreve a padronização dos procedimentos de MCL e de extração de DNA de material fixado em formalina e incluído em parafina. MATERIAL E MÉTODOS: Foram estudados o éxon 8 do gene TP53 e o gene da ciclofilina em amostras de tecido normal e de neoplasias de fígado e rim provenientes de modelo de carcinogênese química induzida em rato. A extração do DNA foi comprovada por reação em cadeia da polimerase (nested-PCR. RESULTADOS: Foram padronizados os procedimentos de preparo dos cortes histológicos, de microdissecção e captura a laser e de obtenção de seqüências gênicas pela reação de nested-PCR para tecidos incluídos em parafina. Obtivemos amplificação de 48,3% das amostras para o éxon 8 do gene TP53 e 51,7% para o gene da ciclofilina. Considerando pelo menos um dos dois segmentos gênicos, foram amplificadas 79,3% das amostras. DISCUSSÃO E CONCLUSÃO: A extração de DNA de tecidos fixados em formalina e incluídos em parafina e a técnica de nested-PCR foram adequadamente padronizadas para produtos gênicos de interesse, obtidos de material coletado por MCL. Esses procedimentos podem ser úteis para a obtenção de seqüências de DNA de arquivos para análise molecular.BACKGORUND: Laser-capture micro-dissection (LCM is a recently developed procedure that provides single cells or specific cell groups for molecular analysis. Currently, there are few LCM systems in Brazil, in such a way that it is necessary to disseminate the technical procedures inherent to the methodology, and also to
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Experimental verification of subthreshold laser therapy using conventional pattern scan laser.
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Tomoyasu Shiraya
Full Text Available Leading-edge therapeutic laser technologies are not available at every medical facility; therefore, alternative approaches incorporating novel advances in digital and laser technology into more readily available conventional methods have generated significant research interest. Using a rabbit model, this study investigated whether the algorithm used in the Endpoint Management (EM software system of the latest devices could enable subthreshold laser treatment in conventional retinal tissue laser therapy systems.Two types of devices were used, the PASCAL Streamline 577 and the MC 500-Vixi™, and the laser method was classified into three categories: EM; single-shot using PASCAL with arbitrary energy settings (PSS-SDM; and MC500-VixiTM (VX-SDM, which were performed in eight eyes from four Dutch-Belted rabbits. In EM, 100 mW (100% was set as a landmark, and the laser energy parameters were gradually decreased to 80%, 60%, 50%, 40%, 30%, 20%, and 10%, using a 2 × 3 square pattern. In PSS-SDM and VX-SDM, as control, the laser energy was gradually decreased to 100, 80, 60, 50, 40, 30, 20, and 10 mW. The laser settings were fixed at 200 μm, 20 ms, and a wavelength of 577 μm. To identify and compare the extent of tissue damage at each spot size, optical coherence tomography (OCT and histological findings were used to construct a three-dimensional histopathology image using a confocal laser scanning fluorescence microscope.The spot size at 50% setting on EM was 7183 μm2; PSS-SDM required 50 mW (5503 μm2 to 60 mW (10279 μm2 and VX-SDM required 50 mW (7423 μm2 to create the approximate spot size. Furthermore, at 50 mW of PSS-SDM and VX-SDM, the extent of tissue damage in all three methods was generally in accord with the outer nuclear layer by OCT and inner nuclear layer by histopathological imaging.These findings suggest that it may be possible to perform subthreshold laser therapy using approximations from the EM algorithm.
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Origem e distribuição anatômica do nervo isquiático de mão-pelada (Procyon cancrivorus
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Kleber F Pereira
2011-12-01
Full Text Available O nervo isquiático é considerado o maior nervo do corpo, pertence tanto ao plexo sacral quanto ao lombossacral em carnívoros, continuando até a extremidade distal do membro pélvico, recebe fiibras dos ramos ventrais do sexto e sétimo nervos lombares e do primeiro nervo sacral. O objetivo do presente estudo é descrever a distribuição do nervo isquiático em mão-pelada (Procyon cancrivorus e comparar com dados literários de animais domésticos e silvestres. Os animais são procedentes de coleta em rodovias, entre as cidades de Goiânia e Jataí, principalmente na BR 364 ou BR 060. (mortos por acidente e fiixados em solução aquosa, a 10% de formaldeído. Doados ao Museu de Anatomia Humana e Comparada da UFG (Universidade Federal de Goiás, Campus de Jataí, Proc.CAJ-287/2008. As dissecações e documentação fotográfiica permitiram observar a distribuição do nervo isquiático. O nervo isquiático de mão-pelada inerva o membro pélvico passando entre os músculos glúteo médio e profundo, emitindo ramos para a musculatura da região glútea e da coxa, respectivamente, para os músculos glúteo médio, glúteo bíceps, semimembranáceo, semitendíneo, bíceps femoral, gêmeos, quadrado femoral e adutor magno, emitindo nervo cutâneo lateral e caudal da sura para suprir a pele na superfiície lateral e caudal da perna, respectivamente. Próximo ao meio da coxa bifurca-se em nervo tibial e nervo fiibular comum. O conhecimento anatômico da origem e distribuição do nervo is quiático em mão pelada quando comparado com animais domésticos, silvestres e de fazenda, mostram um padrão de inervação semelhante entre os espécimes.
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A EFICÁCIA DO LASER NA CICATRIZAÇÃO DE ÚLCERA DE DECÚBITO EM PACIENTE DIABÉTICO: ESTUDO DE CASO
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Luiz Armando Vidal Ramos
2014-08-01
Full Text Available A úlcera de decúbito tornou-se um dos principais problemas de saúde pública devido o maior tempo de internação em hospitais, alcançando índices preocupantes e mortes evitáveis. Desta forma, o estudo tem como objetivo verificar os efeitos da laserterapia de baixa potência como coadjuvante no tratamento de paciente diabético com úlcera de decúbito. Foi investigada e acompanhada uma paciente diabética do Tipo II portadora de úlcera de decúbito, sendo esta idosa, do gênero feminino, idade 83 anos. Essa paciente foi submetida à aplicação de laser tipo Hélio Neônio (Hene, com comprimento de onda de 670 nm, modo pulsado, método pontual, densidade de energia de 6 J/cm2, com duração de 5 minutos em cada ponto, a qual o procedimento ocorreu durante 5 vezes por semana, no período de 6 semanas. A paciente foi avaliada por meio de registros fotográficos e por mensuração da ferida com uma régua milimétrica, em que delimitou a área da úlcera em cm². Observou-se melhora e redução da úlcera de decúbito a partir da terceira sessão. Com base nos resultados deste estudo o laser tipo Hene foi eficaz no tratamento da úlcera de decúbito em paciente diabético no aspecto cicatrização. Palavras-chave: Laser; Úlcera de Decúbito; Diabetes Mellitus; Cicatrização. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v4n2p74-79
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Rogério Gubert Benvindo
2008-01-01
Full Text Available O laser de baixa potência vem sendo usado para acelerar a cicatrização em úlceras de pressão devido a seus efeitos cicatrizante, antiinflamatório, antiedematoso e analgésico. No entanto, não há consenso quanto a seu efeito em úlceras infectadas. O objetivo deste estudo foi verificar o efeito bactericida da laserterapia e da terapia fotodinâmica (TFD com laser de baixa potência, InGaP, 670 nm, em doses de 2, 4 e 6 J/cm², em bactérias gram-positivas e gram-negativas in vitro. Foram preparadas 32 placas de Petri com bactérias, 16 com Pseudomonas aeruginosa e 16 com Staphilococcus aureus. Aleatoriamente dividiu-se cada grupo em oito subgrupos (duas placas cada: três subgrupos tratados só com laserterapia, em doses de 2 J/cm², 4 J/cm² e 6 J/cm²; três subgrupos tratados com TFD, em doses de 2 J/cm², 4 J/cm² e 6 J/cm²; um tratado apenas com fotossensibilizante (azul de metileno a 0,1 µg/ml; e um subgrupo não tratado (controle. Os subgrupos laser e TFD foram irradiados uma única vez e incubados por 24 horas. Os outros dois subgrupos não receberam irradiação. As culturas foram analisadas visualmente para verificação ou não do halo de inibição. Em todos os subgrupos, de ambas as bactérias, não foi observado qualquer halo de inibição nem de crescimento. Conclui-se que a terapia a laser e a fotodinâmica de baixa potência (InGaP, 670 nm não produziram efeitos bactericidas e/ou bacteriostáticos, tampouco tendo havido efeito bioestimulante sobre as bactérias.Low-level laser therapy has been used to speed up healing process of pressure ulcers due to its antiinflammatory, analgesic, anti-edematous, and scarring effects. However there is no consensus on its effect on infected ulcers. The aim of this study was to verify the bactericidal effect of low-level laser therapy (InGaP, 670 nm and photodynamic therapy (PDT at 2, 4 and 6 J/cm² doses, onto gram-negative and gram-positive bacteria in vitro. Thirty two Petri plates
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Poluição luminosa e educação ambiental: um estudo de caso em Camarate, Lisboa
Nunes, Inês de Oliveira; Dourado, Luís Gonzaga Pereira
2017-01-01
A poluição luminosa resulta de candeeiros e projetores exteriores mal concebidos ou mal direcionados, emitindo luz para além do seu alvo. Além do aspeto económico e energético, a poluição luminosa interfere nos processos naturais da fauna e da flora, na qualidade de vida do Homem e na observação do céu noturno. Considerando a problemática local da poluição luminosa de Camarate, desenvolveu-se um projeto interdisciplinar de Educação Ambiental. Realizaram-se auditorias aos equipamentos de ilumi...
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Construção e caracterização de um amplificador em fibra para pulsos ultracurtos em ʎ = 1.5 um
ARIAS, Luis Alfredo Giraldo
2014-01-01
Lasers de pulsos ultracurtos baseados em fibras ópticas como meio de ganho constituem fortes candidatos para substituir lasers de estado sólido mais tradicionais, tais como o laser de Ti:safira. Uma das razões é o custo direto e outra é a possibilidade de compactação de sistemas que ocupam muito espaço e consomem quantidades significativas de energia. Um dos problemas de lasers baseados em fibras ópticas é que a potência óptica média disponível é relativamente baixa, da ordem d...
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Jorge Alfredo Léo
2012-04-01
Full Text Available OBJETIVO: Analisar os efeitos do laser de baixa potência, AsGa - 904 ηm, no reparo ósseo de fraturas de tíbias em ratos. MÉTODOS: 40 ratos divididos em quatro grupos de 10 animais: grupo controle, sem fratura (GC; grupo com fratura, sem tratamento (GE II; grupo com fratura tratado com laser a 10J/cm² (GE III e grupo com fratura tratado com laser a 15J/cm² (GE IV. A fratura foi realizada cirurgicamente e o tratamento teve duração de 45 dias, realizado em dias alternados. Finalizado o tratamento, os ratos foram submetidos à eutanásia e as tíbias tratadas foram radiografadas e submetidas a ensaios mecânicos de flexão em três pontos para avaliar a força máxima (N para ruptura. RESULTADOS: Os valores observados de força máxima (N foram: grupo controle (GC de 51,5N ± 7,9N; GE II de 17,2N ± 7,8N; GE III de 16,6N ± 12,1N e GE IV de 30,3N ± 7,8N. Foram observadas diferenças estatisticamente significantes entre o grupo controle e os grupos experimentais e também entre o grupo experimental IV e os grupos experimentais II e III. Em relação às radiografias, foi observada a formação de calo ósseo em todos os grupos fraturados, indicando que passaram pelo processo normal de reparo tecidual. CONCLUSÃO: O grupo GE IV, submetido à terapia laser com dosagem de 15J/cm² obteve o maior valor para força máxima (N entre os grupos experimentais, indicando a influência da maior dosagem do laser no reparo ósseo.OBJECTIVE: To analyze the effects of low-level laser therapy (GaAs, 904 nm for bone repair on tibial fractures in rats. METHODS: Forty rats were divided into four groups of 10 animals: control group without fracture (CG; fracture group without treatment (EG II; fracture group treated with laser at 10 J/cm² (EG III; and fracture group treated with laser at 15 J/cm² (EG IV. The fracture was produced surgically and the treatment lasted 45 days, done on alternate days. After treatment completion, the rats were sacrificed. The
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Tatiana Bernardon Peixoto Silva
2001-01-01
Resumo: A proposta deste trabalho foi avaliar o desadaptação marginal de infra-estruturas de próteses fixas implanto-suportadas fundidas em monobloco e submetidas à soldagem laser, antes e após a eletroerosão através da análise do assentaIÍlento passivo. Vinte infta-estruturas foram confeccionadas a partir de um modelo mestre metálico com cinco implantes fixados na região inter-forâmes paralelos entre si, e fundidas em titânio comercialmente puro - Ti c. p. (Rematitan - Dentaurum - Pforzhein ...
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Paulo de Tarso Camillo de Carvalho
2010-02-01
Full Text Available PURPOSE: To determine the influence of low-power laser (660 nm on the collagen percentage and macrophages in skin wounds in diabetic rats. METHODS: 30 male Wistar rats were used, distributed in two groups: laser treated diabetic (n= 15; untreated diabetic (n = 15. The diabetes was induced by intravenous injection of alloxan into the dorsal vein of the penis, at a rate of 0.1 ml of solution per 100 g of body weight. A wound was made on the back of all the animals. Groups 2 were treated with Aluminium Gallium Indium Phosphide - InGaAlP type diode laser (Photon Laser III DMC® with a continuous output power of 100 mW and wavelength (? of 660 nm (4 J/cm² for 24 s. five animal from each group was sacrificed on the 3rd, 7th and 14th days after wounding. Samples were taken, embedded in paraffin, stained with hematoxylin-eosin, Masson's trichrome, and immunohistochemical macrophage. morphometrically analyzed using the Image Pro Plus 4.5 software. The percentages of collagen fibers and macrophages were determined from the samples from the euthanasia animals. RESULTS: The data were treated statistically using analysis of variance (ANOVA and the Post-hocTukey test. The significance level was set at 0.05 or 5%. CONCLUSION: The low-power laser (660 nm was shown to be capable of influencing the collagen percentage in skin wounds by increasing the mean quantity of collagen fibers and macrophages.OBJETIVO: Determinar a influência do diodo laser InGaAlP (660 nm sobre o percentual de colágeno e macrófagos em feridas cutâneas de ratos diabéticos. MÉTODOS: Para tanto 30 ratos machos Wistar foram distribuídos em dois grupos: diabético tratado com laser (n=15, diabético não tratado (n = 15. O diabetes foi induzido por injeção intravenosa de aloxana na veia dorsal do pênis, a uma taxa de 0,1 ml de solução por 100 g de peso corporal. A lesão foi confeccionada no dorso de todos os animais utilizando um punch de 8mm. 2 grupos foram tratados com o diodo
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Nathali Cordeiro Pinto
2009-03-01
Full Text Available Deiscência é uma complicação temida em cirurgias de grande porte. Paciente submetida a revascularização miocárdica evoluiu com deiscência de safenectomia em membro inferior, edema e dor no 15º dia pós-operatório (PO, tendo sido realizado inicialmente o tratamento convencional no ambulatório sem melhora clínica. No 30º PO, aplicou-se somente Laser de Baixa Intensidade (LBI ao redor da borda da ferida, pontualmente. A lesão respondeu com tecido de granulação, diminuição do processo inflamatório e analgesia desde a primeira aplicação. Neste estudo piloto, a laserterapia mostrou ter um papel importante como agente facilitador de cicatrização, por meio de uma terapia nãoinvasiva, eficaz e segura.Dehiscence is a feared complication after major surgeries. Patient who had undergone coronary artery bypass grafting developed saphenectomy's dehiscence on lower limb with edema and pain on the 15th postoperative day. Conventional treatment had been initially performed without clinical improvement. On the 30th postoperative day only Low Level Laser Therapy (LLLT was applied punctually around surgical wounds edge. The results revealed granulated tissue, reduction of inflammatory process and analgesic effect since the first application. In this pilot study, LLLT has shown a considerable role as a wound healing agent, through a new proposal for efficient, safe and noninvasive therapy.
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Vicente A. Ventrella
2010-12-01
Full Text Available A soldagem laser vem sendo utilizada como um importante processo de manufatura. Ela pode ser utilizada tanto no modo contínuo quanto no modo pulsado. No processo onde se utiliza laser pulsado é possível realizar soldas de costura em lâminas finas, através da sobreposição dos pulsos. Nesse caso a velocidade de soldagem é definida pela taxa de sobreposição, taxa de repetição e diâmetro do pulso. A soldagem de sobreposição de lâminas finas apresenta problemas típicos como distorção excessiva da junta soldada, falta de contato entre as lâminas a serem soldadas (presença de um gap de ar, perfuração da junta e presença de altos níveis de tensões residuais. O processo de laser pulsado é preferido em relação ao processo por laser contínuo, pois ele possibilita um melhor controle da energia de soldagem. O presente trabalho estudou a influência da energia do pulso, no caso processo de soldagem laser Nd:YAG, na soldagem de lâminas finas ( 100µm de aço inoxidável austenítico AISI 316L, utilizado no revestimento de sensores (que trabalham em ambiente corrosivo da indústria sucroalcooleira. Utilizou-se energia de pulso de 1,0 a 2,25 Joules, com incremento de 0,25 Joules e largura temporal de 4 ms. As soldas foram realizadas com proteção gasosa de argônio. Foram realizadas análises macrográficas das juntas soldadas, através de secções transversais das mesmas e, ensaios de microdureza Vickers e ensaios de tração. Os resultados obtidos mostraram que o controle da energia do pulso, em processo de soldagem por laser de lâminas finas é de fundamental importância para a geração de juntas soldadas com boas propriedades mecânicas e livres de descontinuidades. O limite de resistência da junta soldada aumentou no início e depois sofreu um pequeno decréscimo em função do aumento da energia do pulso. O processo mostrou-se muito sensível à presença de gap entre as lâminas.Laser beam welding has been used widely
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Eliana Barbosa de Souza
2006-09-01
Full Text Available Apical sealing is essential for the success of paraendodontic surgery, so any procedure that may favor an adequate sealing of the apical remainder should be performed. The purpose of this study was to evaluate the influence of diode laser irradiation on the apical sealing of root-end cavities with MTA retrofillings. Root canals in twenty extracted human teeth were shaped with K-files and filled with gutta-percha. The apexes were cut off and root-end preparations were performed. The roots were divided randomly in 2 groups. Group 1 (ten specimens was retrofilled with MTA. Group 2 was irradiated with diode laser, with 1 W for 20 seconds, on the apical surface and root end cavity before retrofilling with MTA. The specimens had their external surfaces impermeabilized with cyanoacrylate, except for the apical surface, and were then immersed in 1% rhodamine B dye for 72 h and placed in plaster stone. After that, the specimens were submitted to longitudinal abrasion until half of the root remained. The linear dye leakage was observed in these mid-roots between the root canal wall and retrofilling. The linear dye leakage was measured with Image Lab software, and the results were statistically analyzed with Student's t test. There were no statistically significant differences between the two groups (p > 0.05. The diode laser irradiation did not improve the apical sealing of MTA retrofillings under the conditions of this in vitro study.O selamento apical é fundamental para o sucesso da cirurgia parendodôntica. Assim, procedimentos que melhorem o selamento do remanescente apical devem ser utilizados. O objetivo deste estudo foi verificar se a irradiação de laser de diodo poderia aumentar o selamento apical em cavidades retrógradas obturadas com MTA. Foram utilizadas 20 raízes de dentes humanos extraídos que, após preparo com lima tipo K, tiveram seus canais obturados com guta-percha. Os ápices foram cortados e sofreram preparo de cavidades retr
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TY Fukuda
2008-02-01
Full Text Available CONTEXTUALIZAÇÃO: A laserterapia de baixa potência vem sendo cada vez mais utilizada, e o crescente interesse por seus efeitos relaciona-se com a grande quantidade de publicações científicas. Muitos terapeutas e pesquisadores têm-se baseado na definição da dose do laser pela densidade energética (deltaE; porém, a grande variedade de equipamentos de laser pode levar a diferença nos resultados terapêuticos encontrados, por fornecerem parâmetros que variam de acordo com o fabricante. OBJETIVO: Analisar a energia final transmitida ao tecido ao aplicar-se a mesma deltaE em equipamentos de diferentes marcas nacionais. MATERIAIS E MÉTODOS: Foram avaliados sete equipamentos nacionais, com potência média (Pm diferentes, e foram realizadas simulações aplicando deltaE de 1J/cm² em cada aparelho, para avaliar possíveis diferenças na energia final. RESULTADOS: A mesmadeltaE aplicada em diferentes aparelhos nacionais forneceu energia final que variou entre 10 e 90mJ. Esta variação na energia deveu-se principalmente a diferenças na Pm, sendo encontrados valores entre 5,4 e 75mW. CONCLUSÃO: Esta variabilidade na energia final, que é transmitida ao tecido, indica que a deltaE parece não ser o parâmetro que melhor descreve a dose a ser utilizada. É preciso mencionar não só a deltaE, mas também a energia final, para que se possa estabelecer a dose para obtenção do melhor resultado terapêutico.INTRODUCTION: Low-level laser therapy is becoming more popular and there is a growing interest in its effects, as reflected in the increased number of articles published about the subject. Many therapists and researchers have used a laser dose definition based on energy density (deltaE. However, the variety of laser equipments may lead to differences in the therapeutic results found, since the parameters supplied by these equipments vary according to the manufacturer. OBJECTIVE: To analyze the final energy transmitted to the tissue when
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Walter NICCOLI-FILHO
2001-06-01
Full Text Available O laser de dióxido de carbono (CO2, pelas suas propriedades intrínsecas, tem se tornado um instrumento cirúrgico importante; entre estas podemos citar: hemostasia, redução do edema e da dor pós-operatória e esterilização do campo cirúrgico. Seu uso em tecido ósseo para realização de osteotomias ainda é questionável, principalmente devido à possibilidade de iatrogenias causadas pelo aumento da temperatura tecidual, bem como destes efeitos na área paraincisional. O propósito deste estudo foi proporcionar a confecção de um plano piloto visando analisar macroscopicamente os efeitos da radiação laser de CO2 em tíbia de rato a fim de estabelecerem-se parâmetros de segurança quanto a potência. Foram utilizados 12 ratos. Após anestesia, os ossos foram submetidos a radiação com potência de 1, 3 e 5 watts. Os animais foram sacrificados nos tempos imediatamente após, 3, 7 e 14 dias após a irradiação, visando à remoção do osso tratado. Os espécimes obtidos foram observados através de lupa estereoscópica com aumentos de 14, 25 e 40 vezes e fotografados para posterior análise. Os resultados permitiram concluir que a potência de 1 watt proporciona uma melhor qualidade de resposta à reparação e que as potências de 3 e 5 watts provocaram o atraso na cronologia de reparo.The use of CO2 laser in osseous tissue to execute osteotomies is still questionable, mainly due to the increase of temperature in the site of irradiation. The purpose of this research was to carry out a pilot study in order to analyze macroscopically the effect of CO2 laser irradiation on rat tibia and to establish security parameters regarding power. Twelve rats were submitted to irradiation with 1, 3 and 5 watts of power and were examined immediately, 3, 7 and 14 days after irradiation. The results showed better healing when irradiation was carried out with the power of 1 watt; the 3- and 5-watt powers caused delay in the chronology of healing.
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Arlei Cerqueira
2007-04-01
Full Text Available PURPOSE: To analyze the microscopic characteristics of the effect of Gallium-Aluminum Arsenid diode laser (GaAlAs - 830etam applied during the activation and consolidation period to ovine mandibles submitted to distraction osteogenesis. METHODS: Eighteen sheep underwent surgery in order to have bone distractors implanted in the left side of the jaw area. They were divided into three groups: 1 - Control; 2 - Laser irradiation during the activation period; 3 - Laser irradiation during the fixation period. The irradiation was carried out in five sessions, on every other day, with 4,0J/cm² doses applied to four pre-established areas, totaling 16J per session. After four days of latency under post-operative care, ten days of distractor activation (at 1mm/day and twenty-one days of fixation the animals were sacrificed and the devices removed for microscopic analysis. RESULTS: The groups that received laser irradiation (GaAlAs presented a greater amount of mineralized bone trabeculae when compared to the Control Group. Despite that, cartilaginous tissues were also found in Group 2. CONCLUSION: The laser has been more favorable when used in the consolidation period, after bone elongation.OBJETIVO: Avaliar as características microscópicas do efeito do laser diodo de Arsenieto de Gálio-Alumínio (AsGaAl - 830etam, aplicado no período de ativação e consolidação de mandíbulas de ovelhas submetidas a distração osteogênica. MÉTODOS: Dezoito ovinos foram submetidos a procedimento cirúrgico para colocação de distrator ósseo em região de mandíbula do lado esquerdo, sendo divididos em três grupos: 1 - Controle; 2 - Irradiação de laser no período de ativação; 3 - Irradiação de laser no período de contenção. As irradiações foram feitas em cinco seções em dias alternados, com doses de 4,0J/cm² em quatro pontos pré-determinados, somando 16J por seção. Após quatro dias de latência no pós-operatório, 10 dias de ativação do
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Adriana Pertille
2012-12-01
ável para a regeneração muscular. OBJETIVO: Avaliar o efeito do tratamento com laser de baixa intensidade sobre a regeneração muscular de modelos experimentais idosos após contusão. MÉTODO: Foram utilizados 25 ratos machos, com 18 meses de idade, divididos em três grupos: grupo controle (CT, sem intervenção; grupo lesão (LE, com contusão muscular e sem tratamento e grupo laser (LA, com contusão muscular e tratado com laser de baixa intensidade, 830 nm, 30 mW e 4 J/cm². A contusão foi realizada no músculo tibial anterior, e as amostras coletadas após sete e 21 sessões de tratamento. O músculo foi designado às técnicas de Microscopia de Luz e Immunoblotting. RESULTADOS: Após 21 dias de tratamento, houve redução significativa na área de inflamação/regeneração no grupo LA 21 comparado ao grupo LE 21. Na área de secção transversal das fibras em processo de regeneração, não houve diferença estatística entre os grupos LA e LE. A análise molecular evidenciou que o conteúdo de MyoD apresentou redução significativa no grupo LE 21 em relação ao CT. O conteúdo de Miogenina exibiu aumento no LE 21 comparado ao CT e, por fim, o conteúdo de TGF-β1 do grupo LE 21 aumentou em relação ao grupo CT. CONCLUSÃO: Para os parâmetros utilizados, o laser demonstrou eficácia na regeneração muscular em animais idosos somente por meio do seu efeito anti-inflamatório.
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Fernando C. C. Santos
2003-12-01
Full Text Available Dentre os vários tipos de laser usados em Medicina, o laser de CO2 é o mais usado na Otorrinolaringologia e Cirurgia de Cabeça e Pescoço. As vantagens de seu uso são a diminuição do sangramento, a diminuição do edema no pós-operatório e a facilidade de acesso ao campo operatório, entre outras. Desde os trabalhos de Jako e Strong em 1972(1,2, quando o laser de CO2 passou a ser usado no tratamento de papilomatose laríngea e de lesões malignas glóticas iniciais, suas indicações têm aumetado, principalmente em lesões benignas, a partir da alta tecnologia desenvolvida dos últimos anos como, por exemplo, a diminuição do microspot e o uso do superpulso, reduzindo conseqüentemente seu efeito térmico sobre os tecidos. MÉTODOS: Neste trabalho foram realizadas incisões com instrumental a frio e com laser de CO2 1 watt de modo contínuo e superpulso, em pregas vocais caninas e observado, através de cortes histológicos corados pelo método de Sirius Red, a quantidade de colágeno depositada sobre as mesmas. RESULTADOS: A quantidade de colágeno das pregas vocais foi maior do que no grupo controle, e estatisticamente maior no grupo de animais submetidos a procedimentos com instrumental a frio do que com laser de CO2. Não houve diferença estatística entre o grupo controle e o grupo submetido a incisões com instrumentos a frio. CONCLUSÃO: A microcirurgia de laringe com o laser de CO2, quando este é usado em baixa potência, com pequeno "microspot" e com superpulso, é um método seguro em relação à deposição de colágeno, quando comparado com instrumentos com lâmina a frio, obedecendo os princípios da fonomicrocirurgia.Among the several types of lasers employed in medicine today, the CO2 is the most widely used in otorhinolaryngology and head and neck surgeries. The advantages of its use are: the reduction in bleeding, reduction in post-operative edema and the easy access to the operation site, among others. Ever since
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Paulo Roberto da Silva Lima
2011-06-01
Full Text Available CONTEXTO: Por ser o laser um método novo no tratamento das varizes, há muitos mitos e dúvidas com relação à sua eficácia; assim, surgiu a necessidade de compará-lo a substância esclerosante mais utilizada em nosso meio (glicose hipertônica. OBJETIVO: Comparar a eficiência do laser diodo 980 nm à glicose 75% na oclusão de veias em orelha de coelho. MÉTODOS: Ensaio aleatório em animais de laboratório por 21 dias. A amostra consistiu de orelhas de coelhos machos adultos. Grupo L (laser: 15 orelhas tratadas com laser; grupo G (glicose 75%: 15 orelhas tratadas com glicose a 75%. Variáveis primárias: veias esclerosadas e/ou ocluídas. Variáveis complementares: volume da substância administrada, complicações e peso. O tamanho da amostra foi estimado em 30 orelhas. Foi realizado o teste exato de Fisher associado ao Risco Relativo (RR, calculando-se o intervalo de confiança (IC de 95% para as variáveis acima. RESULTADOS: A incidência de esclerose ou oclusão venosa no grupo G foi de 53% (8/15; IC95%: 27-79 e no grupo L, 20% (3/15; IC95%: 4-49. O p bicaudal foi de 0,1281, o RR usando a aproximação de Katz foi de 2,66; IC95%: 0,87-8,15. CONCLUSÃO: A eficiência do laser diodo 980 nm em comparação à da glicose 75% na oclusão de veias para o modelo experimental estudado foi equivalente.BACKGROUND: The laser is a new treatment to varicose veins and there is several myths and doubts in relation to its efficacy; then, there is the need to compare it with the most commonly sclerosing solution (hypertonic glucose used in our specialty. OBJECTIVE: To compare the efficiency of the diode laser 980nm to the glucose 75% in the occlusion of veins from the ear of rabbits. METHODS: Aleatory trial in laboratory animals during 21 days. The sample consisted of ears from male adult rabbits. Group L (laser: 15 ears treated with laser; group G (glucose 75%: 15 ears treated with glucose 75%. Primary variables: sclerotic and/or occluded veins
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Fausto Fernandes de Almeida Sousa
2009-01-01
Full Text Available OBJETIVO: Verificar a influência do laser de baixa intensidade de AsGaAl na lesão por esmagamento do nervo peroneiro de ratos através da avaliação funcional da marcha nos diferentes locais de irradiação. MÉTODOS: Foram utilizados 53 ratos, divididos em seis grupos: normal, lesado não tratado, lesado e tratado placebo, lesado e tratado na medula, lesado e tratado no nervo, lesado e tratado em ambos (nervo e medula. O esmagamento do nervo peroneiro foi realizado por meio de uma pinça e subsequente tratado com laser por 28 dias consecutivos. Na avaliação funcional foram analisadas as impressões das pegadas, registradas pela câmera de vídeo em uma passarela de acrílico, no pré-operatório e aos 14º, 21º e 28º dias de pós-operatório, e avaliadas na fórmula PFI por meio do software. RESULTADOS: Na avaliação funcional da marcha foram encontradas diferenças significantes somente no 14º dia de pós-operatório. CONCLUSÃO: A irradiação do laser AsGaAl de baixa intensidade foi capaz de acelerar e potencializar o processo de regeneração nervosa periférica de ratos no 14º dia de pós-operatório, de acordo com a avaliação funcional da marcha, tanto para o grupo tratado na medula quanto para o grupo tratado no nervo.OBJECTIVE: This study seeks to determine, through functional gait assessment in different irradiation sites, the influence of a low-intensity GaAsAl laser beam on an injury caused by crushing the peroneal nerve in rats. METHODS: 53 rats were used, which were divided into six groups: normal, injured and untreated, injured and treated using placebo, injured and treated in the bone marrow, injured and treated in the nerve, and injured and treated in both (nerve and bone marrow. The peroneal nerve was crushed using a pair of tweezers, and subsequently treated with laser for 28 consecutive days. The functional gait evaluation analyzed the footprints, which were recorded with a video camera on an acrylic bridge in the
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Sisti, Karin Ellen
2011-01-01
Objetivo: Estudar a topografia a osseointegração de implantes de titânio sob ação do LASER de alta intensidade com e sem deposição química de hidroxiapatita, em coelhos. Método: Foram utilizados 30 coelhos albinos que receberam em suas tíbias 3 tipos de superfície de implantes: grupo controle(GI) implantes usinados, grupo(GII) irradiado LASER(Yb), e grupo irradiado e depositado hidroxiapatita pelo método biomimético(GIII). Após os períodos de avaliações (30 e 60 dias) os implantes foram subme...
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Cristiano Schiavinato Baldan
2012-02-01
Full Text Available PURPOSE: To investigate the effects of different low-level laser therapy (LLLT doses on random skin flap rats. METHODS: Forty Wistar rats were randomly divided in four groups. The control group (CG was not irradiated. The experimental groups were irradiated with a diode laser 670 nm with different energies per point: group 2 (G2 with 0.06 J; group 3 (G3 0.15 J and group 4 (G4 0.57 J. The three groups were irradiated in 12 equally distributed points in the cranial skin flap portion. They were submitted to the irradiation during the immediate, first and second postoperative days. The necrosis area was evaluated in the seventh postoperative day. RESULTS: The CG shows 49.35% of necrosis area in the skin flap; G2, 39.14%; G3, 47.01% and G4, 29.17% respectively. There was a significantly difference when G4 was compared with CG`s skin flap necrosis area. CONCLUSION: The low-level laser therapy diode 670 nm with 0.57 J energy per point increases the survival in randomic skin flap rats.OBJETIVO: Investigar os efeitos de diferentes doses de laserterapia de baixa intensidade na viabilidade de retalhos cutâneos randômicos em ratos. MÉTODOS: Quarenta ratos Wistar foram randomizadamente distribuídos em quatro grupos. O grupo controle (GC não foi irradiado. Os animais dos grupos experimentais foram irradiados por laser de diodo (670 nm com as seguintes energias ofertadas por ponto: grupo 2 (G2 0,06J; grupo 3 (G3 0,15 J e grupo 4 (G4 0,57 J. Os três grupos foram irradiados em 12 pontos igualmente distribuídos na porção cranial do retalho cutâneo. Todos os animais dos grupos 2, 3 e 4 foram submetidos ao protocolo de irradiação por três dias consecutivos, iniciando no pós-operatório imediato. A área necrótica foi avaliada no sétimo dia pós-operatório. RESULTADOS: A porcentagem de área necrótica apresentou-se da seguinte forma, nos diferentes grupos: GC= 49,35%, G2= 39,14%, G3= 47,01 e G4= 29,17%. Foi encontrada diferença estatisticamente
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Multiplatform Mobile Laser Scanning: Usability and Performance
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Yuwei Chen
2012-08-01
Full Text Available Mobile laser scanning is an emerging technology capable of capturing three-dimensional data from surrounding objects. With state-of-the-art sensors, the achieved point clouds capture object details with good accuracy and precision. Many of the applications involve civil engineering in urban areas, as well as traffic and other urban planning, all of which serve to make 3D city modeling probably the fastest growing market segment in this field. This article outlines multiplatform mobile laser scanning solutions such as vehicle- and trolley-operated urban area data acquisition, and boat-mounted equipment for fluvial environments. Moreover, we introduce a novel backpack version of mobile laser scanning equipment for surveying applications in the field of natural sciences where the requirements include precision and mobility in variable terrain conditions. In addition to presenting a technical description of the systems, we discuss the performance of the solutions in the light of various applications in the fields of urban mapping and modeling, fluvial geomorphology, snow-cover characterization, precision agriculture, and in monitoring the effects of climate change on permafrost landforms. The data performance of the mobile laser scanning approach is described by the results of an evaluation of the ROAMER on a permanent MLS test field. Furthermore, an <em>in> <em>situ> accuracy assessment using a field of spherical 3D targets for the newly-introduced Akhka backpack system is conducted and reported on.
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Clarissa Tôrres Leal
2012-09-01
Full Text Available O objetivo desta revisão sistemática foi analisar o efeito do laser de HeNe na cicatrização de feridas em ratos. Foram selecionados estudos experimentais que adotaram o laser HeNe para o tratamento de feridas agudas em ratos adultos saudáveis, com lesões induzidas por bisturi, nas bases de dados PubMed/MEDLINE, LILACS e SciELO. Foram utilizados os seguintes descritores: cicatrização de feridas e colágeno, de acordo com o MeSH e o DeCS, além dos unitermos laser HeNe e reparação da pele e seus equivalentes em inglês e espanhol. Três estudos foram incluídos na revisão sistemática, não sendo possível a realização de metanálise, devido à impossibilidade de comparação entre as metodologias dos estudos selecionados. Todos os estudos realizaram análise por meio de cortes histológicos das cicatrizes. A presença de falhas metodológicas nos três artigos dificultou a interpretação fidedigna dos dados encontrados. Os estudos destacaram uma redução na intensidade da resposta inflamatória e uma melhor organização das fibras colágenas no grupo irradiado. A terapia com laser HeNe mostrou boa resposta no reparo tecidual. No entanto, tais resultados devem ser analisados de modo criterioso, uma vez que há presença de heterogeneidade, principalmente em relação aos parâmetros adotados.The aim of this systematic review was to analyze the effect of HeNe laser on wound healing in rats. Experimental studies that adopted HeNe laser as a treatment of acute lesions in healthy adult rats were selected, with scalpel-induced lesions, at PubMed/MEDLINE, LILACS, and SciELO databases. The following keywords were used: wound healing and collagen, according to MeSH and DeCS, besides the terms HeNe laser and skin repair, and their equivalent in Portuguese and Spanish. Three studies were included in this systematic review, but it was not possible to perform a metanalysis, due to impossibility to compare methods of the selected studies. All
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Mariana Kuhl Cidade
2016-12-01
Full Text Available Esta pesquisa trata da geração de referência de padronização na utilização da tecnologia de corte a laser CO2 em borracha EPDM, através do desenvolvimento de joias contemporâneas. Foram conduzidos diversos testes de aplicação de velocidades e número de passadas de feixe laser a fim de determinar a configuração ideal para utilização deste processo no material. Imagens analisadas via MEV auxiliaram a compreensão dos efeitos do feixe laser no elastômero, como a zona de abrangência térmica e a efetividade do corte. Com a melhor definição de corte para um traço uniforme, essa caracterização objetiva auxiliar estudantes, profissionais e indústrias na execução de seus projetos.
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Deep learning and model predictive control for self-tuning mode-locked lasers
Baumeister, Thomas; Brunton, Steven L.; Nathan Kutz, J.
2018-03-01
Self-tuning optical systems are of growing importance in technological applications such as mode-locked fiber lasers. Such self-tuning paradigms require {\\em intelligent} algorithms capable of inferring approximate models of the underlying physics and discovering appropriate control laws in order to maintain robust performance for a given objective. In this work, we demonstrate the first integration of a {\\em deep learning} (DL) architecture with {\\em model predictive control} (MPC) in order to self-tune a mode-locked fiber laser. Not only can our DL-MPC algorithmic architecture approximate the unknown fiber birefringence, it also builds a dynamical model of the laser and appropriate control law for maintaining robust, high-energy pulses despite a stochastically drifting birefringence. We demonstrate the effectiveness of this method on a fiber laser which is mode-locked by nonlinear polarization rotation. The method advocated can be broadly applied to a variety of optical systems that require robust controllers.
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Lúcia de Noronha
2001-01-01
Full Text Available O presente estudo tem como objetivo analisar, do ponto de vista anatomopatológico, os efeitos térmicos encontrados na pele de ratos wistar após a aplicação do laser de CO2 e do laser erbium. Utilizaram-se oito ratos submetidos a tricotomia em toda a região toracodorsal. Selecionaram-se duas áreas separadas, as quais receberam a aplicação do laser. Na primeira foram realizadas duas passadas do laser de CO2 e na segunda, duas passadas do laser erbium. A área-controle correspondeu àquela imediatamente adjacente à área submetida ao laser. A análise microscópica da lesão causada pelo laser de CO2 revela lesão em forma de U, com ablação completa da epiderme em toda a sua extensão. A derme superficial apresenta degeneração do colágeno, correspondendo ao dano térmico residual, e a transição deste para a derme normal é bem demarcada. Na pele lesada com laser erbium observa-se também extensa área de pele lesada em forma de platô, com algumas pequenas áreas de pele não-lesada. Pode-se observar, ainda, dano do colágeno na derme superficial, porém mais discreto que aquele causado pelo CO2.The aim of this paper is to analyses the histopathology of the termal effects on the skin of Wistar rats after the application of CO2 and erbium laser. Eight rats had their flanks shaved and two areas were selected for the use of the laser. The first area received two applications of CO2 laser, and the second area two applications of the erbium laser. The skin adjacent to the laser application site was used as a control area. The microscopic analysis of the injury caused by CO2 laser revealed a complete ablation of epidermis and an injury that looked like an "U" in shape. The superficial dermis presented a degeneration of the collagen that corresponded to the residual thermal injury, to normal dermis was sharply demarcated. The injury caused by erbium laser was observed as a plateau injured area with a few small normal areas. The collagen
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Firoozmand, Leily Macedo
2007-01-01
Full Text Available O objetivo desta pesquisa foi o de avaliar o comportamento clínico do laser Nd: YAG em comparação ao de um selante com carga, durante o período de 12 meses, observando; a pigmentação do sulco, incidência de cárie e fratura ou perda do selante. Foram selecionados 62 primeiros e segundos premolares hígidos de pacientes na faixa etária de 12 a 15 anos, de uma escola da rede pública de São José dos Campos. Nos 31 primeiros premolares foi aplicado o laser Nd: YAG, Pulse Máster 600 IQ em toda a extensão do sulco oclusal por 30 segundos utilizando 60 mJ, 10 HZ, 0,6W. Nos 31 segundos premolares foi realizado o selamento dos sulcos oclusais com o selante Fluorshield. Após 6 meses observou-se que dos casos selados com Fluorshield 19,35% apresentaram perda e/ou fratura do selante e em 16,66% os sulcos apresentaram cárie incipiente. Já nos casos em que foi aplicado o laser Nd: YAG 6,45% apresentaram início de lesão de cárie. Com 12 meses de avaliação tanto com selante Fluorshield como com o laser Nd: YAG observou-se o aparecimento de sulcos pigmentados em 12, 90% dos casos e uma incidência de 9,67% de lesões incipientes de cárie. Utilizando-se o selante Fluorshield houve queda do material em 25,80% e fratura em 3,22% dos casos. Concluímos que após 12 meses de avaliação o laser Nd: YAG e o selante Fluorshield apresentaram comportamento clínico semelhante, diante das mesmas condições bucais, sendo que a porcentagem de aparecimento de lesão inicial de cárie foi igual para os dois métodos de prevenção utilizados
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LASERTERAPIA EM AFECÇÕES LOCOMOTORAS: REVISÃO SISTEMÁTICA DE ESTUDOS EXPERIMENTAIS
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Maria Verônica de Souza
2016-02-01
Full Text Available RESUMO Introdução: Ao longo dos anos a fisioterapia tem contribuído para o tratamento das lesões musculotendíneas e osteoarticulares pela utilização de diversos recursos eletrotermofototerapêuticos como, por exemplo, o laser de baixa potência. Objetivo: A finalidade desse estudo foi identificar mediante revisão sistemática, o efeito da laserterapia de baixa potência em afecções do sistema locomotor de ratos, com destaque para a dose de energia e o comprimento de onda utilizado, assim como para a resposta ao tratamento. Métodos: Foram consultadas as bases de dados Medline, Lilacs, PEDro e SciELO, entre janeiro de 2005 a maio de 2013, utilizando os termos "tendinopathy", "laser therapy", "rats", "tendon", "muscle", "bone", "low-level laser therapy", assim como "tendinopatia", "laserterapia", "ratos", "tendão", "músculo", "osso" e "laser de baixa potência". Apenas foram incluídos estudos experimentais publicados nos idiomas português e inglês, que induziram lesão em tendões, músculos, ossos e/ou articulação, tratada com laserterapia, associada ou não a outros tratamentos. Resultados: Foi encontrado um total de 30 estudos experimentais nas bases de dados consultadas, dos quais 15 (50% foram realizados em tendão, 10 (33,33% em músculo e cinco (16,66% em osso e/ou articulação. As doses de energia mais comumente utilizadas foram de 3 J (26,66% e 1 J (16,66%. Já os comprimentos de onda foram de 904 nm (21,21% e 830 nm (21,21%. Conclusão: A informação mais expressiva obtida com a terapia foi a diminuição da resposta inflamatória (36,66% em lesões ortopédicas agudas.
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Enfermeiros e clientela com bulimia e anorexia: estudo de caso
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Claudia Regina Carvalho Martins
2012-06-01
Full Text Available Investigação que objetivou identificar a interação de enfermeiros e clientes portadores de bulimia e anorexia. Utilizamos o estudo de caso como recurso, para o qual coletamos dados de prontuários e fizemos entrevistas com oito de quatorze enfermeiros, que foram nossos sujeitos-objeto. De acordo com os enfermeiros, os clientes se isolavam do mundo, vivendo num mundo sem fome e de espelhos que refletiam um corpo sempre acima do "peso ideal"; eram pessoas solitárias, que perderam o brilho pessoal, emitindo sinais de que podiam extinguir a vida deles a qualquer momento. Com o estudo, foi possível identificar a maneira pela qual os enfermeiros interagiam e percebiam os clientes e, em decorrência disso, explicitamos uma prática de cuidar peculiar na enfermagem.
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Lúcia de Noronha
2001-06-01
Full Text Available Lasers de CO2 tem sido apresentados com a finalidade de rejuvenecer a face através do resurfacing. Embora cada sistema de laser tenha o mesmo princípio básico, há significativa diferença entre os lasers que pode resultar em variações no efeito tecidual clínico e histológico. O laser Erbium:YAG que tem como característica o comprimento de onda com 10 vezes mais afinidade pela água que o laser de CO2. O propósito deste estudo experimental foi comparar as alterações morfométricas encontradas em 2 e 4 passadas com laser Erbium:YAG com sobreposição de 0% dos spots. Foi avaliada a homogeneidade da ablaçãoem comprimento e usou-se a pele do dorso de 3 ratos in vivo. Foi selecionada uma área de pele controle de cada rato. Finalmente, num período máximo de 3 horas, a pele foi ressecada e encaminhada à histopatologia para as avaliações propostas. Como resultados com 4 passadas houve mais homogeneidade da extensão da ablação do que em 2 passadas. Conclui-se que a extensão e homogeneidade de ablação foi maior com 4 passadas. A utilização de 0% de sobreposição dos spots não garante homogeneidade de ablação.CO2 lasers has been presented with the purpose of rejuvenating the face by means of resurfacing. Though each laser systems has the same base principle, there is a significant difference among lasers which could result in variations in the clinical and histological effects of the tissue. The Erbium:YAG laser has the characteristic of having the wavelength with 10 times more affinity for water than the CO2 laser. The purpose of this experimental study was to compare the morphometric alterations found in 2 and 4 Erbium:YAG laser passes with 0% overlap of spots. It was evaluated the homogeneity of ablation in length and was used the dorsal skin of 3 living mice. It was selected a control area in each mouse. Finally, in the maximum period of three hours, the skin was resected and sent to histopathology for evaluations
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2015-01-01
analytical Beer - Lambert absorption profile to model laser heating of pure energetic crystals without considering any EM wave propagation effects...temperature. These aggregates were studied using both an analytical distribution for laser heating following Beer - Lambert absorption and the full EM finite...surface (ysurface - y) and material absorption coefficient, α, following a Beer - Lambert absorption relation given by , = !()
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Lucia Noronha
2005-10-01
Full Text Available INTRODUÇÃO: Diferente do lifting, cuja tração mecânica é a responsável pelo efeito clínico de rejuvenescimento sobre rugas profundas, a fibroplasia (ou neocolagenização é a responsável direta pelo resultado final da ação do laser sobre a pele com rugas superficiais, conferindo-lhe aparência mais jovem. O uso combinado dessas duas técnicas pode ser vantajoso, pois permite um resultado estético melhor com um único procedimento anestésico e cirúrgico em um curto período de recuperação. OBJETIVOS: O presente estudo morfométrico se propõe a avaliar se ocorre alguma alteração na espessura da fibroplasia induzida pelo resurfacing a laser erbium:YAG quando este se associa ao lifting cutâneo. MÉTODO: Foram utilizados 50 ratos da linhagem Wistar, divididos em dois grupos de 25, sendo que o primeiro grupo foi submetido à aplicação exclusiva de laser erbium:YAG no dorso de cada animal e o outro sofreu a aplicação de laser Erbium: YAG combinada ao lifting, o qual foi representado, no animal de experimentação, por retalho cutâneo dorsal pediculado. A fibroplasia foi avaliada nos dois grupos com medidas morfométricas lineares realizadas após o sacrifício dos animais nos dias 14, 28, 56, 84 e 112 do pós-operatório. RESULTADO: Foi observado aumento da fibroplasia em ambos os grupos estudados, porém o crescimento do colágeno foi superior no grupo submetido à terapia isolada com laser Erbium: YAG. CONCLUSÃO: A espessura da fibroplasia induzida pelo resurfacing a laser Erbium: YAG foi influenciada pela associação de um segundo procedimento cirúrgico no mesmo tempo operatório, neste caso, o lifting cutâneo.INTRODUCTION: The fibroplasia is the responsible for the final aesthetic results induced by laser resurfacing upon skin with superficial wrinkles. On the other hand, the lifting is responsible for the deeper wrinkles removal, produced by mechanic results. The use of the combination of these two rejuvenation
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Terapia pulpar em dentes decíduos: possibilidades terapêuticas baseadas em evidências
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Natalino Lourenço Neto
Full Text Available INTRODUÇÃO: A pulpotomia em dentes decíduos é uma técnica conservadora de terapia pulpar amplamente utilizada em Odontopediatria, sendo de fundamental importância para evitar a perda prematura desses dentes, quer seja por alterações provocadas pela cárie dentária ou traumatismo dentário. Apesar de ser uma técnica estudada há muitos anos, causa muitas controvérsias e discussões, principalmente em termos de biocompatibilidade dos medicamentos empregados e pelas dificuldades e falhas no diagnóstico da condição pulpar. OBJETIVO: Por meio de uma revisão sistemática da literatura, no período compreendido entre 2000 e 2011, e com enfoque em estudos clínicos randomizados, revisões sistemáticas e meta-análises, este trabalho teve como objetivo discutir, com base em evidências científicas, alternativas para o tratamento de pulpotomia em dentes decíduos humanos. CONCLUSÃO: As evidências científicas fidedignas com o uso de materiais capeadores pulpares e as técnicas de Eletrocirurgia e Laser de Baixa Potência foram escassas. Desta forma, sugere-se a realização de estudos complementares bem delineados estatisticamente para maiores esclarecimentos. As informações geradas em tais experimentos poderão contribuir para um melhor entendimento dos mecanismos da terapia pulpar, podendo gerar o desenvolvimento de protocolos com novas formas terapêuticas, que visam a melhorar a terapia pulpar em dentes decíduos.
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Cláudia Barros dos Santos
2011-01-01
Neste trabalho, fez-se a inserção de duas grades de difração matriciais com guias de onda, ou AWGs (Arrayed Waveguide Gratings) em uma cavidade laser de fibra dopada com Érbio, onde um único meio de ganho em temperatura ambiente pode gerar ação laser em múltiplos comprimentos de onda, com emissões simultâneas e controladas individualmente. A configuração utilizada permitiu o teste com diferentes regimes de operação simultâneos dentro da cavidade. Mostramos a possibilidade de emissão laser em ...
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Lucio Almeida Castagno
2006-12-01
Full Text Available Otite média secretora (OMS e otite média aguda recorrente (OMAR podem necessitar tratamento cirúrgico para adequada ventilação da orelha média. A abertura clássica do tímpano (timpanocentese requer incisão por microlanceta sob controle de microscópio cirúrgico e mantém-se patente por alguns dias. Estudos recentes sugerem que a timpanocentese feita por diferentes lasers pode permanecer permeável por maior tempo, o que possibilitaria a normalização da otite média. MATERIAL E MÉTODOS: Neste estudo experimental 34 ratos linhagem Wistar, albinos, machos adultos pesando cerca de 300g, foram anestesiados com cetamina 27 mg/kg e xilazina 2,7 mg/kg. A seguir, foram submetidos à timpanocentese incisional com microlanceta no ouvido direito (ML-OD, e à timpanocentese mediada por laser de argônio no ouvido esquerdo (LA-OE. RESULTADOS: Não houve diferença significativa no tempo de cicatrização das timpanocenteses feitas com laser de argônio ou microlanceta. Todas as timpanocenteses cicatrizaram em 10 dias. CONCLUSÃO: A timpanocentese com laser de argônio apresentou patência e cicatrização semelhantes à técnica clássica com microlanceta realizada em ratos Wistar sem enfermidades de orelha média.Secretory otitis media (SOM and recurrent acute otitis media (RAOM may require surgical treatment to proper ventilate the middle ear. Incisional myringotomy is usually done under microscopy with a micro-knife , but it remains patent for just a few days. Recent research indicates that laser assisted myringotomies remain open much longer, allowing middle ear ventilation and healing. MATERIAL AND METHODS: In this experimental study 34 white, male, adult, Wistar rats, without middle ear disease were submited to anesthesia with ketamine 27 mg/kg and xylazine 2,7 mg/kg. Incisional myringotomy was done on the right ear, while laser myringotomy was done on the left. Myringotomies were evaluated periodically until healing. RESULTS: The healing
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Núbia Broetto Cunha
2008-04-01
Full Text Available A ciatalgia deve-se a compressão do nervo isquiático em algum ponto de seu trajeto, e seu tratamento consiste em solucionar a causa da compressão nervosa, seja por tratamento cirúrgico ou conservador. Alguns recursos fisioterapêuticos atuam basicamente na redução dos sintomas ocasionados por este distúrbio. O objetivo deste estudo foi verificar a eficácia do laser 670 nm, em duas diferentes densidades de energia, na redução do quadro álgico, em ratos submetidos a modelo experimental de ciatalgia. Foram utilizados 18 ratos, divididos em 3 grupos: G1 (n=6 submetidos à ciatalgia e simulado o tratamento (grupo placebo, G2 (n=6 submetido à ciatalgia e tratados com laser 2 J/cm², G3 (n=6 submetidos à ciatalgia e irradiados com laser 4 J/cm². O nervo isquiático do membro posterior direito dos animais foi exposto e compressão com fio catgut em 4 pontos ao redor do nervo foi realizada. No 3° dia pós-operatório, iniciou-se o tratamento com laser na região do procedimento cirúrgico do membro posterior direito durante 10 dias consecutivos. Verificou-se por meio da marcha, o tempo em que o membro permanecia no ar nos períodos: anterior à ciatalgia, pré e pós-tratamento. Os resultados demonstraram que o laser não foi eficaz na redução do quadro álgico, porém com 4 J/cm² houve efeito positivo, sem restabelecimento completo da funcionalidade.Sciatica is caused by the sciatic nerve compression in some point of its course, and its treatment consists of solving the nervous compression cause, either by surgical or conservative treatment. Some physiotherapeutic resources act basically in the reduction of the symptoms caused by this disturbance. The aim of this study was to verify the effectiveness of the laser 670 nm, in two different energy densities, in the pain reduction, in rats submitted to a sciatica experimental model. Eighteen rats, divided in 3 groups were used: G1 (n=6 submitted to sciatica and simulated treatment (placebo
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Mehrdad Shoroghi
2011-08-01
Full Text Available PURPOSE: To investigate and compare the efficacy of oral midazolam with two different dosages in orange juice on perioperative hemodynamics and behavioral changes in children who underwent skin laser treatment in an academic educational Hospital. METHODS: Ninety children, candidates for skin laser treatment were randomly assigned to 1 of 3 groups of 30 each: the placebo group received 0.1 ml/kg orange flavored juice, group 2 and 3 receiving 0.5 and 1 mg/kg of injectable midazolam mixed with an equal volume of orange juice, respectively. The main outcome measures included the mask acceptance, patients' behavioral scales and postoperative events. RESULTS: There were no significant differences in heart rate, respiratory rate, and systolic blood pressure among the three groups. However, arterial oxygen saturation was significantly reduced in those given 1 mg.kg-1 midazolam. The median scores of anxiety, separation from parent, preparing an intravenous line, acceptance of the oxygen mask, good sedation, crying reduction and consciousness level were better in midazolam group. Postoperative agitation and re-crying were also more frequent in placebo receivers. Those given 1 mg.kg-1 midazolam were significantly more optimal for sedation, crying, consciousness, preparing an intravenous line, and postoperative re-crying compared with 0.5 mg.kg-1 midazolam receivers. CONCLUSION: As a preanaesthetic medication, the 1 mg.kg-1 dose of orally given midazolam especially in a volume of orange juice and can optimize the children's behavior during skin laser treatment with no serious adverse effects, enhancing their parents' satisfactions about the sedative protocol.OBJETIVO:Investigar e comparar a eficácia do uso oral de midazolam com duas diferentes doses de suco de laranja na hemodinâmica peropeatória e mudanças de desempenho em crianças submetidas tratamento de pele por laser em Hospital educacional e acadêmico. MÉTODOS:Noventa crianças candidatas a
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Christiane Rolim de Moura
2003-12-01
Full Text Available PURPOSE: To compare the results of scanning laser polarimetry of the retinal nerve fiber layer obtained by using the GDx Scanning Laser System® in primary open angle glaucoma (POAG and nonglaucomatous Brazilian subjects over 40 years, also analyzing the differences between the data obtained from right and left eyes. METHODS: Forty-six POAG patients and 44 normal subjects were enrolled in this study. Retardation data were assessed by the GDx Scanning Laser System®. The medians of the parameters printed in the result were compared in these two groups, separately in the right and left eyes, using Mann-Whitney's test. Also the frequencies of outside normal parameters and quadrants of deviation from normal graph were compared in these two groups, using chi-square or Fisher's exact test. RESULTS: All parameters obtained by GDx differed in a statistically significant way between the two groups, except symmetry for left eyes. The frequency of inferior quadrant with pOBJETIVOS: Comparar os resultados da polarimetria de varredura a laser da camada de fibras nervosas obtidas por meio do GDx Scanning Laser System® em brasileiros portadores de glaucoma primário de ângulo aberto e indivíduos não glaucomatosos acima de 40 anos, analisando também as diferenças obtidas entre olhos direitos e esquerdos. MÉTODOS: Foram incluídos neste estudo 46 pacientes portadores de glaucoma primário de ângulo aberto e 44 pacientes normais. Os dados de retardo polarimétrico foram obtidos por meio do GDx Scanning Laser System®. As medianas dos parâmetros impressos no resultado foram comparadas nesses dois grupos, separadamente para olhos direitos e esquerdos, usando o teste de Mann-Whitney. A freqüência de parâmetros impressa como fora da normalidade e quadrantes estatisticamente alterados do gráfico "deviation from normal" foram comparados nesses dois grupos usando chi-quadrado e o teste exato de Fischer. RESULTADOS: Todos os parâmetros obtidos pelo GDx
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EFICÁCIA CLÍNICA DO LASER ACUPUNTURAL NO TRATAMENTO DA DESORDEM TEMPOROMANDIBULAR
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Diego Rodrigues Pessoa
2016-12-01
Full Text Available A disfunção temporomandibular (DTM é a condição mais frequente de dor orofacial crônica. A DTM é caracterizada pela a presença de sinais e sintomas na região orofacial. A acupuntura e Terapia a laser de baixa intensidade (TLBI vêm sendo empregadas no tratamento da DTM. A acupuntura consiste na inserção de agulhas em acupontos específicos do corpo para promover efeitos terapêuticos. A TLBI é uma modalidade de tratamento não invasiva, que vem sendo utilizada com frequência na prática clínica para o tratamento das DTM. Diante do exposto, o objetivo deste estudo foi realizar revisão de literatura, acerca da eficácia clinica do laser acupuntural em pacientes com a DTM. O emprego do laseracupuntural no tratamento das DTM favorece o controle antálgico, miorrelaxante e anti-inflamatório, no entanto, são necessárias novas pesquisas acerca do tema para determinar a eficácia do laser acupuntural em longo prazo para o tratamento de desordens temporomandibulares.
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Xuefeng Zhang
2012-05-01
Full Text Available Fluorescence<em> em>
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Chad H. Stahl
2012-05-01
Full Text Available Satellite cell activity is necessary for postnatal skeletal muscle growth. Severe phosphate (PO4 deficiency can alter satellite cell activity, however the role of neonatal PO4 nutrition on satellite cell biology remains obscure. Twenty-one piglets (1 day of age, 1.8 ± 0.2 kg BW were pair-fed liquid diets that were either PO4 adequate (0.9% total P, supra-adequate (1.2% total P in PO4 requirement or deficient (0.7% total P in PO4 content for 12 days. Body weight was recorded daily and blood samples collected every 6 days. At day 12, pigs were orally dosed with BrdU and 12 h later, satellite cells were isolated. Satellite cells were also cultured <em>in vitroem> for 7 days to determine if PO4 nutrition alters their ability to proceed through their myogenic lineage. Dietary PO4 deficiency resulted in reduced (<em>P> < 0.05 sera PO4 and parathyroid hormone (PTH concentrations, while supra-adequate dietary PO4 improved (<em>P> < 0.05 feed conversion efficiency as compared to the PO4 adequate group. <em>In vivoem> satellite cell proliferation was reduced (<em>P> < 0.05 among the PO4 deficient pigs, and these cells had altered <em>in vitroem> expression of markers of myogenic progression. Further work to better understand early nutritional programming of satellite cells and the potential benefits of emphasizing early PO4 nutrition for future lean growth potential is warranted.
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LASER hemorrhoidal dearterialization
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Paulo Boarini
2017-01-01
.O objetivo deste trabalho é descrever os resultados de 55 pacientes com doença hemorroidária tratados pela técnica HeLP. Método: Sem a necessidade de anestesia, as arteríolas terminais da artéria retal superior são identificadas através de um transdutor doppler (20mhz probe de 3 mm locado em um proctoscópio especialmente desenhado. Após a identificação, promove-se a eletrofulguração arteriolar através de uma fibra de 980 nm de diiodo LASER, ocasionando interrupção do hiperfluxo hemorroidário. Este procedimento é repetido circunferencialmente, seguindo-se as posições das horas de um relógio. Resultados: Entre 2011 e 2014, 55 pacientes foram submetidos a técnica HeLP para doença hemorroidária de graus I, II e III. Nenhum paciente utilizou anestesia e apenas dois necessitaram sedação para a realização do procedimento. O índice de satisfação global atingiu 89%, houve resolução dos sintomas em 84% e diminuição de ao menos um grau, na doença hemorroidária, em 80% dos casos. Conclusão: HeLP é uma técnica ambulatorial e indolor, que não utiliza qualquer anestesia, é segura e fácil de ser realizada. Eficiente para reduzir sintomas e complicações da doença hemorroidária graus I e II, com índice de satisfação elevada. Keywords: Hemorrhoids, Hemorrhoidal LASER Procedure, Hemorrhoidal dearterialization, Palavras-chave: Hemorroidas, Hemorrhoidal LASER Procedure, Desarterialização hemorroidária
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Emerson Borato
2008-10-01
Full Text Available O laser de baixa potência induz a bioestimulação celular, podendo acelerar a cicatrização de feridas, promover a regeneração do músculo esquelético, diminuir a resposta inflamatória, estimular a neoformação de vasos sanguíneos e diminuir a dor. O objetivo deste estudo foi analisar os efeitos de três doses de laser de baixa intensidade (808nm, na dor e edema imediatos, em ratos submetidos a lesão experimental do músculo gastrocnêmio lateral. Foram utilizados 24 ratos Wistar, distribuídos aleatoriamente em quatro grupos, sendo: GC - animais lesionados e tratados com aparelho desligado (simulacro; G20 - animais lesionados e irradiados com dose de 20J/cm²; G50 - animais lesionados e irradiados com 50J/cm; e G100 - animais lesionados e irradiados com 100J/cm². Para a produção da lesão experimental, introduziu-se 0,1mL de formalina a 5% no ventre do músculo gastrocnêmio lateral direito. A avaliação da dor ocorreu através do tempo de elevação da pata (TEP e o edema foi avaliado com auxílio de paquímetro metálico; ambas as avaliações ocorreram pré-lesão, pós-lesão, pós-tratamento, duas, oito e 24 horas pós-lesão. Os resultados mostraram aumento significativo do TEP e da avaliação com paquímetro, após a indução da lesão. Conclui-se que laser nos parâmetros utilizados não produziu diminuição na dor e edema, em animais submetidos a lesão muscular com injeção de formalina a 5%.Low-level laser therapy induces to cellular bioestimulation and can accelerate wound healing, promote skeletal muscle regeneration, decrease inflammatory response, stimulate neovascularization and decrease pain. The aim of this study was to analyze the effects of three doses of low-level laser therapy (808 nm, in the immediate pain and edema, in rats submitted to experimental injury of the lateral gastrocnemius muscle. Twenty four Wistar rats, randomly distributed in the following four groups were used: CG - injured and treated
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Photoactive dye enhanced tissue ablation for endoscopic laser prostatectomy
Ahn, Minwoo; Nguyen, Trung Hau; Nguyen, Van Phuc; Oh, Junghwan; Kang, Hyun Wook
2015-02-01
Laser light has been widely used as a surgical tool to treat benign prostate hyperplasia with high laser power. The purpose of this study was to validate the feasibility of photoactive dye injection to enhance light absorption and eventually to facilitate tissue ablation with low laser power. The experiment was implemented on chicken breast due to minimal optical absorption Amaranth (AR), black dye (BD), hemoglobin powder (HP), and endoscopic marker (EM), were selected and tested in vitro with a customized 532-nm laser system with radiant exposure ranging from 0.9 to 3.9 J/cm2. Light absorbance and ablation threshold were measured with UV-VIS spectrometer and Probit analysis, respectively, and compared to feature the function of the injected dyes. Ablation performance with dye-injection was evaluated in light of radiant exposure, dye concentration, and number of injection. Higher light absorption by injected dyes led to lower ablation threshold as well as more efficient tissue removal in the order of AR, BD, HP, and EM. Regardless of the injected dyes, ablation efficiency principally increased with input parameter. Among the dyes, AR created the highest ablation rate of 44.2+/-0.2 μm/pulse due to higher absorbance and lower ablation threshold. Preliminary tests on canine prostate with a hydraulic injection system demonstrated that 80 W with dye injection yielded comparable ablation efficiency to 120 W with no injection, indicating 33 % reduced laser power with almost equivalent performance. In-depth comprehension on photoactive dye-enhanced tissue ablation can help accomplish efficient and safe laser treatment for BPH with low power application.
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X-ray laser related experiments and theory at Princeton
International Nuclear Information System (INIS)
Suckewer, S.
1989-04-01
This paper describes a new system for the development of an x-ray laser in the wavelength region from 5 nm to 1 nm utilizing a Powerful Sub-Picosecond Laser (PP-Laser) of expected peak power up to 0.5 TW in a 300 fs pulse. Soft x-ray spectra generated by the interaction of the PP-Laser beam with different targets are presented and compared to the spectra generated by a much less intense laser beam (20--30 GW). A theoretical model for the interaction of atoms with such a strong laser EM field is also briefly discussed. The development of additional amplifiers for the recombining soft x-ray laser and the design of a cavity are presented from the point of view of applications for x-ray microscopy and microlithography. This overview concludes with the presentation of recent results on the quenching of spontaneous emission radiation and its possible effect on the absolute intensity calibration of soft x-ray spectrometers. 26 refs., 18 figs
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Alberto Diniz Filho
2008-10-01
Full Text Available The term plateau iris was first coined in 1958 to describe the iris configuration of a patient. Two years later the concept of plateau iris was published. In 1977, the plateau iris configuration was classically defined as presurgical changes of an eye with a relative normal central anterior chamber depth, flat iris by conventional biomicroscopy, but displaying an extremely narrow or closed angle on gonioscopic examination. On the other hand, the plateau iris syndrome was defined as an acute glaucoma crisis in one eye with a relative normal central anterior chamber depth and patent iridotomy on direct examination, presenting angle closure confirmed by gonioscopic examination after mydriasis. In 1992, the anatomic aspects of plateau iris were studied using ultrasound biomicroscopy. Finally, plateau iris has been considered an anatomic variant of iris structure in which the iris periphery angulates sharply forward from its insertion point and then again angulates sharply and centrally backward, along with an anterior positioning of the ciliary processes seen on ultrasound biomicroscopy. The clinical treatment of plateau iris syndrome is carried out with topical use of pilocarpine. However, the definitive treatment should be fulfilled by performing an argon laser peripheral iridoplasty.O termo íris em platô foi primeiramente inventado em 1958 para descrever a configuração da íris de um paciente. Dois anos depois o conceito de íris em platô foi publicado. Em 1977, a configuração de íris em platô foi classicamente definida como alterações pré-cirúrgicas de um olho com uma profundidade de câmara anterior relativamente normal, íris plana pela biomicroscopia convencional, mas mostrando um ângulo extremamente estreito ou fechado pela gonioscopia. Por outro lado, a síndrome de íris em platô foi definida como uma crise de glaucoma agudo em um olho com uma profundidade de câmara anterior relativamente normal e uma iridectomia patente ao
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Christel Lingnau
2008-09-01
Full Text Available O presente estudo tem como principal objetivo a obtenção de variáveis dendrométricas de árvores em um povoamento de Pinus sp a partir de dados laser scanner terrestre. O povoamento de pinus possui quarenta anos de idade, já sofreu desbastes, e apresenta uma densidade de cerca de 890 arv./ha. A metodologia iniciou-se com a coleta de dados de forma tradicional e com o equipamento ILRIS-3D (OPTECH. Com o auxilio de GPS geodésico e estação total determinou-se coordenadas de alvos na fl oresta que serviram de base para georreferenciamento do scanner. A varredura foi realizada em um giro de 360 graus com resoluções de 10 mm e 50 mm a 50 metros em dois pontos distintos do povoamento. Os dados da varredura foram processados com o intuito de isolar efiltrar uma árvore. Como resultado, chegou-se a um bom isolamento de árvores e fi ltragem de pontos, obteve-se ainda a altura total de 31,93 metros e alturas parciais em intervalos de 1 metro relativas a uma árvore do povoamento. A tecnologia laser scanner terrestre apresenta potencial promissor para área florestal abrangendo a aplicação em inventáriosflorestais, planejamento de manejo, produção e colheita florestal.
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Maria Helena Chaves de Vasconcelos Catão
2013-12-01
Full Text Available OBEJTIVO: avaliar a eficácia do laser de baixa intensidade no tratamento da dor em pacientes com desordens temporomandibulares. MÉTODO:consistiu de um ensaio clínico randomizado divididos em dois grupos: Grupo 1: laser AsGaAl, Grupo 2: laser InGaAlP, do qual participaram 20 pacientes entre 19 e 35 anos de idade, com diagnóstico de sinais e sintomas de DTM. Os pacientes tinham a amplitude de movimento para abertura máxima da boca e lateralidade registados no início e no final do tratamento a laser. O Laser foi aplicado em quatro pontos pré-auriculares, totalizando 12 sessões três vezes por semana, durante um mês. Dor dos pacientes foi registrado com base na utilização da escala analógica visual (EAV e também por exame físico dos pontos álgicos. RESULTADOS: observou-se redução significante (p<0,028 do nível de dor em ambos os grupos, porém no G1 a significância foi maior. A evolução do limiar de sensibilidade muscular evidenciou diferença estatisticamente significante (p<0,05 para G1 e G2. A laserterapia no Grupo 1 melhorou a abertura bucal em média de 4,643 mm, enquanto no Grupo 2, a média foi de 3,71 mm por paciente. CONCLUSÃO: houve eficácia em ambos os lasers no controle da dor e abertura bucal dos pacientes.
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Energy Technology Data Exchange (ETDEWEB)
Cordon, Rosely
2003-07-01
The low intensity laser therapy (LILT) has been extensively used in medicine and dentistry presenting positive effects. However, the laser radiation can also cause adverse effects. Due to the ocular focalization property, in the wavelength from 400 to 1400 nm, the retina is more susceptible to damage by radiation than any other part of the human body. Then, the ocular protection is frequently emphasized. This protection must attenuate the radiation to a safe level. The International Electrotechnical Commission (IEC) standard IEC 60825-1 suggests safety requirements for medical laser equipment, including the ocular protection, based on maximum permissible exposure levels. The Brazilian legislation adopts a corresponding IEC standard, the NBR IEC 601.2.22, for safety requirements. The aim of this study was to analyze the adequacy of the ocular protectors furnished by four laser equipment manufacturers, commercially available in Brazil, commonly used for LILT. For this purpose, the laser equipment and the respective ocular protectors were characterized. The adequacy was verified according to the IEC standards. It was found, among other results, ocular protectors attenuating to safe levels the radiation emitted by the respective laser equipment, however, presenting inadequate visual transmission. Inefficient protection and protection indicated in cases where they were not necessary were also observed. (author)
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Reference Gene Selection in the Desert Plant <em>Eremosparton songoricuem>m>
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Dao-Yuan Zhang
2012-06-01
Full Text Available <em>Eremosparton songoricum em>(Litv. Vass. (<em>E. songoricumem> is a rare and extremely drought-tolerant desert plant that holds promise as a model organism for the identification of genes associated with water deficit stress. Here, we cloned and evaluated the expression of eight candidate reference genes using quantitative real-time reverse transcriptase polymerase chain reactions. The expression of these candidate reference genes was analyzed in a diverse set of 20 samples including various <em>E. songoricumem> plant tissues exposed to multiple environmental stresses. GeNorm analysis indicated that expression stability varied between the reference genes in the different experimental conditions, but the two most stable reference genes were sufficient for normalization in most conditions.<em> EsEFem> and <em>Esα-TUB> were sufficient for various stress conditions, <em>EsEF> and <em>EsACT> were suitable for samples of differing germination stages, and <em>EsGAPDH>and <em>Es
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Lais Mara Siqueira das Neves
2011-01-01
Full Text Available OBJETIVO: Investigar os possíveis efeitos da laserterapia com laser diodo 830nm ao se contrapor a ação da nicotina na viabilidade do retalho cutâneo em ratos. MÉTODOS: Foram utilizados 16 ratos Wistar, distribuídos em 2 grupos de 8: Grupo 1- submetido à técnica cirúrgica, para obtenção dos retalhos cutâneos randômicos de base cranial, com injeção subcutânea de nicotina em uma dose de 2mg/Kg/dia, uma semana antes e uma semana após o procedimento cirúrgico e simulação da radiação laser; Grupo 2- similar ao grupo 1, cujos retalhos cutâneos randômicos de base cranial foram submetidos à irradiação do laser imediatamente após a cirurgia e nos 4 dias subsequentes. Após a eutanásia, as áreas de necrose e de tecido viável foram examinadas através do método de pesagem do Gabarito de Papel e pelo método semi-automático de análise de imagens (Mini-Mop®. RESULTADOS: Os resultados foram analisados estatisticamente através do teste ANOVA. Os valores de porcentagem de área de necrose através do método de análise mostraram uma diminuição da área de necrose no grupo 2 onde foi aplicado laser. CONCLUSÃO: O laser 830nm foi eficaz na melhora da viabilidade do retalho cutâneo em ratos submetido à ação da nicotina. Nível de evidência II: Estudos terapêuticos - Investigação dos resultados do tratamento.OBJECTIVE: To investigate the possible effects of laser diode 830nm counter to the action of nicotine on the viability of the skin flap in rats. METHODS: 24 Wistar-albino rats were used, divided into 3 groups of 8: Group 1 - subject to the surgical technique to obtain the random skin flap in cranial base, subcutaneous injection of nicotine of 2mg/Kg/dia a week before and one week after surgery and simulation of laser. Group 2 - similar to group 1, the random skin flap in the cranial base were subjected to laser irradiation immediately after surgery and on thesubsequent 4 days. After euthanasia, areas of necrosis and
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André Peres e Serra
2010-06-01
Full Text Available JUSTIFICATIVA E OBJETIVOS: A fototerapia com laser (LPT é um método analgésico promissor, embora seu mecanismo de ação não seja totalmente conhecido. O objetivo deste estudo foi avaliar se a ação da LPT é dependente da ativação de receptores opioides ou serotoninérgicos periféricos. MÉTODO: Foram utilizados ratos Wistar machos. A dor produzida foi de caráter inflamatório, através da injeção de carragenina na pata posterior esquerda dos ratos. O laser utilizado foi o Photon Lase III em meio ativo InGaAIP (660 nm, fluência de 2,5 J.cm-2. Analisou-se a hiperalgesia mecânica utilizando filamentos de von Frey. Os animais foram separados em cinco grupos: Carragenina; Laser (LPT; Luz não coerente; LPT + Naloxona e LPT + Metisergida. RESULTADOS: A fototerapia com laser em baixa intensidade mostrou-se um método analgésico eficaz, enquanto o emprego de fonte de luz não coerente não mostrou ter efeito analgésico. O uso de naloxona bloqueou o efeito analgésico do LPT; já o uso de metisergida não afetou a analgesia do LPT. CONCLUSÕES: A LPT nos parâmetros utilizados apresentou efeito analgésico. A analgesia da LPT é mediada por receptores opioides periféricos. A LPT parece não interagir com receptores serotoninérgicos periféricos.JUSTIFICATIVA Y OBJETIVOS: La fototerapia con láser (LPT es un método analgésico promisorio, aunque su mecanismo de acción no se conozca en su totalidad. El objetivo de este estudio fue evaluar si la acción de la LPT es dependiente de la activación de receptores opioides o serotoninérgicos periféricos. MÉTODO: Se usaron ratones Wistar machos. El dolor generado fue de carácter inflamatorio, a través de la inyección de carragenina en la pata posterior izquierda de los ratones. El láser utilizado fue el GaIAsAl (660 nm, fluencia de 2,5 J.cm-2. Se analizó la hiperalgesia mecánica utilizando filamentos de von Frey. Los animales se dividieron en cinco grupos: Carragenina; Láser (LPT
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Energy Technology Data Exchange (ETDEWEB)
Kar, S., E-mail: s.kar@qub.ac.uk; Ahmed, H.; Nersisyan, G.; Hanton, F.; Naughton, K.; Lewis, C. L. S.; Borghesi, M. [Centre for Plasma Physics, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom); Brauckmann, S.; Giesecke, A. L.; Willi, O. [Institut für Laser-und Plasmaphysik, Heinrich-Heine-Universität, Düsseldorf (Germany)
2016-05-15
As part of the ultrafast charge dynamics initiated by high intensity laser irradiations of solid targets, high amplitude EM pulses propagate away from the interaction point and are transported along any stalks and wires attached to the target. The propagation of these high amplitude pulses along a thin wire connected to a laser irradiated target was diagnosed via the proton radiography technique, measuring a pulse duration of ∼20 ps and a pulse velocity close to the speed of light. The strong electric field associated with the EM pulse can be exploited for controlling dynamically the proton beams produced from a laser-driven source. Chromatic divergence control of broadband laser driven protons (upto 75% reduction in divergence of >5 MeV protons) was obtained by winding the supporting wire around the proton beam axis to create a helical coil structure. In addition to providing focussing and energy selection, the technique has the potential to post-accelerate the transiting protons by the longitudinal component of the curved electric field lines produced by the helical coil lens.
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Energy Technology Data Exchange (ETDEWEB)
Mueller, Karin Praia
2004-07-01
The purpose of this study was to investigate the effects of low intensity laser therapy, associated or not to an acidulated phosphate fluoride, on the prevention of dental caries induced in rats. It was used 40 wistar rats, female, weaned with 18 days, fed with a cariogenic diet during 48 days and inoculated orally with Streptococcus mutans by three consecutive days starting from the second day of the diet. On the fifth day of experiment the animals were divided into five groups: G{sub c} (control) the animas were no submitted to any treatment; G{sub L} (laser) irradiation with low power laser (GaAlAs, {lambda}=660 nm, P=30 mW, {delta}t=5 sec, 5 J/cm{sup 2}); G{sub F} (fluoride) topical application of acidulated phosphate fluoride (APF 1,23%) for four minutes; G{sub LF} (laser + fluoride) irradiation with low power laser followed by topical application of acidulated phosphate fluoride; G{sub FL} (fluoride + laser) topical application of acidulated phosphate fluoride followed by low power laser. The animals were sacrificed after 48 days; the molars were extracted and prepared to determine the dental caries lesions area by optical microscopy, enamel microhardness and analysis of the calcium and phosphorus ratio (Ca/P) by energy dispersive spectroscopy. The results were statistically analyzed by ANOVA (p
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Directory of Open Access Journals (Sweden)
Giovanni Ferrara
1992-07-01
Full Text Available Abstract In a lot of Barn Owl's pellets from the Murge plateau a specimen of <em>Sorex> sp. was detected. Thank to some morphological and morphometrical features, the cranial bones can be tentatively attributed to <em>Sorex samniticusem> Altobello, 1926. The genus <em>Sorex> was not yet included in the Apulia's fauna southwards of the Gargano district; the origin and significance of the above record is briefly discussed, the actual presence of a natural population of <em>Sorex> in the Murge being not yet proved. Riassunto Viene segnalato il rinvenimento di un esemplare di <em>Sorex> cfr. <em>samniticus> da borre di <em>Tyto albaem> delle Murge. Poiché il genere non era stato ancora segnalato nella Puglia a sud del Gargano, viene discusso il significato faunistico del reperto.
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Directory of Open Access Journals (Sweden)
Lizarazo H. Karol
2008-12-01
Full Text Available
El gusano cogollero <em>Spodoptera frugiperdaem> es una de las plagas que más afectan los cultivos en la región de Sumapaz (Cundinamarca, Colombia. En la actualidad se controla principalmente aplicando productos de síntesis química, sin embargo la aplicación de extractos vegetales surge como una alternativa de menor impacto sobre el ambiente. Este control se emplea debido a que las plantas contienen metabolitos secundarios que pueden inhibir el desarrollo de los insectos. Por tal motivo, la presente investigación evaluó el efecto insecticida y antialimentario de extractos vegetales de barbasco <em>Polygonum hydropiperoidesem> (Polygonaceae, carbonero <em>Calliandra pittieriem> (Mimosaceae y hierba mora <em>Solanum nigrumem> (Solanaceae sobre larvas de <em>S. frugiperdaem> biotipo maíz. Se estableció una cría masiva del insecto en el laboratorio utilizando una dieta natural con hojas de maíz. Posteriormente se obtuvieron extractos vegetales utilizando solventes de alta polaridad (agua y etanol y media polaridad (diclorometano los cuales se aplicaron sobre las larvas de segundo instar. Los resultados más destacados se presentaron con extractos de <em>P. hydropiperoidesem>, obtenidos con diclorometano en sus diferentes dosis, con los cuales se alcanzó una mortalidad de 100% 12 días después de la aplicación y un efecto antialimentario representado por un consumo de follaje de maíz inferior al 4%, efectos similares a los del testigo comercial (Clorpiriphos.
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Vanessa Ovanessian Fukuda
2011-10-01
Full Text Available OBJETIVO: Este estudo foi designado para avaliar a eficácia a curto prazo da laserterapia de baixa intensidade (LBI na melhora da dor e função em pacientes portadores de osteoartrite (OA do joelho. MÉTODOS: Participaram deste ensaio clínico aleatório, duplo-cego e controlado 47 pacientes (79 joelhos de ambos os sexos portadores de OA do joelho, que foram distribuídos aleatoriamente em dois grupos; grupo laser com 25 pacientes (41 joelhos e grupo placebo com 22 pacientes (38 joelhos. A LBI foi realizada três vezes por semana totalizando nove sessões, com uso do laser AsGa de 904nm, 60mW de potência média e 0,5cm² de área do feixe, sendo irradiados nove pontos no joelho com energia de 3,0J por ponto. O grupo placebo foi tratado com o mesmo aparelho de laser, porém com uma caneta selada. As avaliações Lequesne, escala visual numérica (EVN, Timed Up and Go (TUG, goniometria e dinamometria foram realizadas antes do início do tratamento e após as nove sessões da LBI. RESULTADOS: Foi encontrada melhora significante da dor e função para todas as avaliações aplicadas no grupo laser. Quando comparado o grupo laser ao grupo placebo encontrou-se diferença significante para as avaliações EVN-Repouso e Lequesne. CONCLUSÃO: O tratamento com a LBI melhora a dor e função a curto prazo de pacientes portadores de OA do joelho.OBJECTIVE: This study was designed to evaluate the short-term efficacy of low-level laser therapy (LLLT for improving pain and function in patients with knee osteoarthritis. METHODS: Forty-seven patients with knee osteoarthritis (79 knees, of both genders, participated in this randomized controlled double-blind clinical trial. They were randomly allocated to two groups: laser group with 25 patients (41 knees and placebo group with 22 patients (38 knees. LLLT was performed three times a week, totaling nine sessions, using a AsGa 904 nm laser with mean power of 60 mW and beam area of 0.5 cm². Nine points were
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Carolina de Lourdes Julião Vieira Rocha
2012-09-01
Full Text Available CONTEXTO: A terapia a laser de baixa intensidade (LLLT tem sido relatada como importante moduladora da cicatrização de feridas cutâneas aumentando a proliferação fibroblástica associada ao aumento da expressão da citocina fator transformador de crescimento- β2 (TGF-βB2. OBJETIVO: No presente estudo foram avaliados os efeitos da LLLT sobre a expressão da enzima ciclooxigenase 2 (COX2 no sítio do reparo tecidual utilizando o modelo experimental com camundongos diabéticos não obesos (NOD para estudar a cicatrização de feridas cutâneas. MÉTODOS: Foram utilizados 30 camundongos NOD, destes 14 ficaram diabéticos e foram divididos em dois grupos: o grupo I (n=7 foi submetido a um procedimento cirúrgico de feridas cutâneas e o grupo II (n=7 foi submetido a um procedimento cirúrgico de feridas cutâneas e tratados com LLLT. O grupo II foi submetido à LLLT nos seguintes parâmetros: 15 mW de potência, dose de 3,8 J/cm² e tempo de aplicação de 20 segundos. Após sete dias do ato cirúrgico e após aplicação do laser, os animais foram eutanasiados com sobredose de anestesia e amostras das feridas foram colhidas para posterior análise histopatológica, histomorfométrica e imuno-histoquímica. RESULTADOS: A LLLT promoveu a inibição da expressão da COX2 em feridas cutâneas de camundongos diabéticos. CONCLUSÃO: Em conjunto, os resultados sugeriram que a LLLT é capaz de modular negativamente a expressão da enzima COX2 contribuindo para o controle da resposta inflamatória em feridas cutâneas de camundongos NOD.BACKGROUND: Low-level laser therapy (LLLT has been reported to modulate the healing of wounds by inducing an increase in fibroblast number associated with increased expression of the cytokine transforming growth factor-β2 (TGF-β2. OBJECTIVE: In the present study, the effect of LLLT on expression of COX2 at the site of tissue repair was evaluated, using an experimental model with non obese diabetic mice (NOD to study
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Jung-Ha Kang
2012-06-01
Full Text Available The mottled skate, <em>Raja pulchraem>, is an economically valuable fish. However, due to a severe population decline, it is listed as a vulnerable species by the International Union for Conservation of Nature. To analyze its genetic structure and diversity, microsatellite markers were developed using 454 pyrosequencing. A total of 17,033 reads containing dinucleotide microsatellite repeat units (mean, 487 base pairs were identified from 453,549 reads. Among 32 loci containing more than nine repeat units, 20 primer sets (62% produced strong PCR products, of which 14 were polymorphic. In an analysis of 60 individuals from two <em>R. pulchra em>populations, the number of alleles per locus ranged from 1–10, and the mean allelic richness was 4.7. No linkage disequilibrium was found between any pair of loci, indicating that the markers were independent. The Hardy–Weinberg equilibrium test showed significant deviation in two of the 28 single-loci after sequential Bonferroni’s correction. Using 11 primer sets, cross-species amplification was demonstrated in nine related species from four families within two classes. Among the 11 loci amplified from three other <em>Rajidae> family species; three loci were polymorphic. A monomorphic locus was amplified in all three <em>Rajidae> family species and the <em>Dasyatidae> family. Two <em>Rajidae> polymorphic loci amplified monomorphic target DNAs in four species belonging to the Carcharhiniformes class, and another was polymorphic in two Carcharhiniformes species.
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Viviane L. Busnardo
2010-02-01
Full Text Available OBJETIVO: Avaliar os efeitos do laser de baixa potência hélio e neônio (HeNe na cicatrização de feridas cutâneas de ratos. MÉTODOS: Sessenta ratos Wistar foram divididos em grupos controle e experimento. Utilizou-se ferida incisional, longitudinal, dorso-mediana, suturada com pontos separados simples. No grupo experimento, as feridas foram irradiadas diariamente com aparelho de laser de HeNe com potência contínua máxima de 5mW, comprimento de onda de 632,8 nm, visível com densidade de energia de 4J/cm², área de raio do laser de 0,015cm², durante 36 segundos, em três pontos da lesão. As feridas foram avaliadas no 3º, no 7º e no 14º dia de pós-operatório. Cortes histológicos foram corados com hematoxilina-eosina (H&E e avaliados segundo protocolo de Vizzotto et al. (2003* para identificar o tipo de reação inflamatória e com Picrosirius para identificar os colágenos I e III e o índice de maturidade da cicatriz (IMaC. Utilizou-se imunoistoquímica com anti-CD45-LCA para o reconhecimento das células inflamatórias. RESULTADOS: Ambos os grupos mostraram o mesmo padrão inflamatório. No grupo experimento, observaram-se menos células inflamatórias nos três tempos estudados (pOBJECTIVE: To evaluate the effects of low-level helium-neon (HeNe laser on cutaneous wound healing in rats. METHODS: Sixty Wistar rats were divided into control group and experimental group. A sutured longitudinal, dorsal-medial incision was made, with simple separate stitches. The experimental group was irradiated daily in three areas of the wound with HeNe laser (5mW maximum continuous power, 632.8 nm wavelength, 4 J/cm² energy density and 0.015 cm² laser beam area for 36 seconds. The areas were evaluated on the third, seventh and fourteenth days postoperative. Histological sections were stained with hematoxylin-eosin to determine the type of inflammatory reaction according to the protocol by Vizzotto et al. (2003* and with Picrosirius to identify
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A New Natural Lactone from <em>Dimocarpus> <em>longan> Lour. Seeds
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Zhongjun Li
2012-08-01
Full Text Available A new natural product named longanlactone was isolated from <em>Dimocarpus> <em>longan> Lour. seeds. Its structure was determined as 3-(2-acetyl-1<em>H>-pyrrol-1-yl-5-(prop-2-yn-1-yldihydrofuran-2(3H-one by spectroscopic methods and HRESIMS.
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Lucio Hirokuni Kanashiro
2005-01-01
Este estudo avaliou a precisão de duas técnicas de união, a brasagem e a soldagem a laser, em estruturas metálicas de uma prótese clássica de Brånemark. Dez estruturas fundidas em NiCr foram segmentadas em 4 partes e analisadas no MEV em pontos pré-estabelecidos, vestibular e proximal, totalizando 8 pontos de análise para cada estrutura. Na primeira fase, foi mensurada a fenda marginal existente entre o análogo do implante e o abutment UCLA antes da união destes segmentos através da brasagem ...
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Yijun Fan
2012-07-01
Full Text Available A water-soluble polysaccharide (BEBP was extracted from <em>Boletus edulis em>Bull using hot water extraction followed by ethanol precipitation. The polysaccharide BEBP was further purified by chromatography on a DEAE-cellulose column, giving three major polysaccharide fractions termed BEBP-1, BEBP-2 and BEBP-3. In the next experiment, the average molecular weight (Mw, IR and monosaccharide compositional analysis of the three polysaccharide fractions were determined. The evaluation of antioxidant activities both <em>in vitroem> and <em>in vivo em>suggested that BEBP-3 had good potential antioxidant activity, and should be explored as a novel potential antioxidant.
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Ricardo Belfort
2008-02-01
Full Text Available OBJETIVO: Avaliar a qualidade de vida e de visão e o estresse de pacientes portadores de ametropias submetidos a procedimentos cirúrgicos. MÉTODOS: Estudo longitudinal observacional em que foram estudados 100 pacientes; 54 usuários de óculos, 21 usuários de lentes de contato interessados no procedimento cirúrgico e 25 controles usuários de óculos ou lentes de contato, mas que não desejavam ser operados no período de um ano. Os questionários aplicados foram o National Eye Institute Visual Function Questionnaire (NEI-VFQ-25 de qualidade de vida e o Self Reporting Questionnaire - SRQ-20 para avaliação da saúde mental. Os pacientes que se submeteram à cirurgia responderam aos questionários aplicados por uma observadora antes da mesma, três, seis e doze meses após a intervenção. O grupo controle respondeu de forma auto-aplicada no início do estudo, seis e doze meses após a primeira avaliação. RESULTADOS: No grupo da cirugia dos 54 pacientes que usavam óculos 39 fizeram cirurgia de ceratectomia fotorrefrativa por excimer laser(PRK e 15 fizeram ceratomileuse assistida por excimer laserin situ (LASIK e dos 21 que usavam lentes de contato 12 fizeram cirurgia de ceratectomia fotorrefrativa e nove fizeram ceratomileuse assistida por excimer laser in situ (LASIK. O grupo controle esteve estável durante os 12 meses em relação aos instrumentos aplicados. Três meses após a cirurgia o grupo da cirurgia apresentou melhora significante da qualidade de vida e de visão em relação ao pré-operatório independentemente do tipo de cirurgia realizada. Um ano após a cirurgia os índices de qualidade de vida e de saúde mental, foram semelhantes aos do grupo controle. O Self Reporting Questionnaire - SRQ 20 mostrou diminuição significante do índice de sintomas a partir dos três meses de pós-operatório. CONCLUSÃO: A qualidade de visão e de vida dos pacientes submetidos à cirurgia de correção de ametropia mudou
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Marta Magi
2010-06-01
Full Text Available Abstract During 2004-2005 and 2007-2008, 189 foxes (<em>Vulpes vulpesem> and 6 badgers (<em>Meles melesem> were collected in different areas of Central Northern Italy (Piedmont, Liguria and Tuscany and examined for <em>Angiostrongylus vasorumem> infection. The prevalence of the infection was significantly different in the areas considered, with the highest values in the district of Imperia (80%, Liguria and in Montezemolo (70%, southern Piedmont; the prevalence in Tuscany was 7%. One badger collected in the area of Imperia turned out to be infected, representing the first report of the parasite in this species in Italy. Further studies are needed to evaluate the role played by fox populations as reservoirs of infection and the probability of its spreading to domestic dogs.
Riassunto <em>Angiostrongylus vasorumem> nella volpe (<em>Vulpes vulpesem> e nel tasso (<em>Meles melesem> in Italia centro-settentrionale. Nel 2004-2005 e 2007-2008, 189 volpi (<em>Vulpes vulpesem> e 6 tassi (<em>Meles melesem> provenienti da differenti aree dell'Italia settentrionale e centrale (Piemonte, Liguria Toscana, sono stati esaminati per la ricerca di <em>Angiostrongylus vasorumem>. La prevalenza del nematode è risultata significativamente diversa nelle varie zone, con valori elevati nelle zone di Imperia (80% e di Montezemolo (70%, provincia di Cuneo; la prevalenza in Toscana è risultata del 7%. Un tasso proveniente dall'area di Imperia è risultato positivo per A. vasorum; questa è la prima segnalazione del parassita in tale specie in Italia. Ulteriori studi sono necessari per valutare il potenziale della volpe come serbatoio e la possibilità di diffusione della parassitosi ai cani domestici.
doi:10.4404/hystrix-20.2-4442 -
NATO Advanced Study Institute on Laser Interactions with Atoms, Solids,and Plasmas
1994-01-01
The aim of this NATO Advanced Study Institute was to bring together scientists and students working in the field of laser matter interactions in order to review and stimulate developmentoffundamental science with ultra-short pulse lasers. New techniques of pulse compression and colliding-pulse mode-locking have made possible the construction of lasers with pulse lengths in the femtosecond range. Such lasers are now in operation at several research laboratories in Europe and the United States. These laser facilities present a new and exciting research direction with both pure and applied science components. In this ASI the emphasis is on fundamental processes occurring in the interaction of short laser pulses with atoms, molecules, solids, and plasmas. In the case of laser-atom (molecule) interactions, high power lasers provide the first access to extreme high-intensity conditions above 10'8 Watts/em', a new frontier for nonlinear interaction of photons with atoms and molecules. New phenomena observed include ...
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Mohammad Anis
2012-05-01
Full Text Available An efficient method was developed for plant regeneration and establishment from alginate encapsulated synthetic seeds of <em>Rauvolfia serpentinaem>. Synthetic seeds were produced using <em>in vitroem> proliferated microshoots upon complexation of 3% sodium alginate prepared in Llyod and McCown woody plant medium (WPM and 100 mM calcium chloride. Re-growth ability of encapsulated nodal segments was evaluated after storage at 4 °C for 0, 1, 2, 4, 6 and 8 weeks and compared with non-encapsulated buds. Effects of different media <em>viz>; Murashige and Skoog medium; Lloyd and McCown woody Plant medium, Gamborg’s B5 medium and Schenk and Hildebrandt medium was also investigated for conversion into plantlets. The maximum frequency of conversion into plantlets from encapsulated nodal segments stored at 4 °C for 4 weeks was achieved on woody plant medium supplement with 5.0 μM BA and 1.0 μM NAA. Rooting in plantlets was achieved in half-strength Murashige and Skoog liquid medium containing 0.5 μM indole-3-acetic acid (IAA on filter paper bridges. Plantlets obtained from stored synseeds were hardened, established successfully <em>ex vitroem> and were morphologically similar to each other as well as their mother plant. The genetic fidelity of <em>Rauvolfia em>clones raised from synthetic seeds following four weeks of storage at 4 °C were assessed by using random amplified polymorphic<em> em>DNA (RAPD and inter-simple sequence repeat<em> em>(ISSR markers. All the RAPD and ISSR profiles from generated plantlets were monomorphic and comparable<em> em>to the mother plant, which confirms the genetic<em> em>stability among the clones. This synseed protocol could be useful for establishing a particular system for conservation, short-term storage and production of genetically identical and stable plants before it is released for commercial purposes.
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A.M. Paci
2003-10-01
Full Text Available Lo scopo del contributo è di fornire un aggiornamento sulla presenza del Toporagno del Vallese <em>Sorex antinoriiem>, del Toporagno acquatico di Miller <em>Neomys anomalusem> e della Talpa cieca <em>Talpa caecaem> in Umbria, dove le specie risultano accertate ormai da qualche anno. A tal fine sono stati rivisitati i reperti collezionati e la bibliografia conosciuta. Toporagno del Vallese: elevato di recente a livello di specie da Brünner et al. (2002, altrimenti considerato sottospecie del Toporagno comune (<em>S. araneus antinoriiem>. È conservato uno di tre crani incompleti (mancano mandibole ed incisivi superiori al momento prudenzialmente riferiti a <em>Sorex> cfr. <em>antinorii>, provenienti dall?Appennino umbro-marchigiano settentrionale (dintorni di Scalocchio - PG, 590 m. s.l.m. e determinati sulla base della pigmentazione rossa degli ipoconi del M1 e M2; Toporagno acquatico di Miller: tre crani (Breda in Paci e Romano op. cit. e un esemplare intero (Paci, ined. sono stati trovati a pochi chilometri di distanza gli uni dall?altro tra i comuni di Assisi e Valfabbrica, in ambienti mediocollinari limitrofi al Parco Regionale del M.te Subasio (Perugia. In provincia di Terni la specie viene segnalata da Isotti (op. cit. per i dintorni di Orvieto. Talpa cieca: sono noti una femmina e un maschio raccolti nel comune di Pietralunga (PG, rispettivamente in una conifereta a <em>Pinus nigraem> (m. 630 s.l.m. e nelle vicinanze di un bosco misto collinare a prevalenza di <em>Quercus cerrisem> (m. 640 s.l.m.. Recentemente un terzo individuo è stato rinvenuto nel comune di Sigillo (PG, all?interno del Parco Regionale di M.te Cucco, sul margine di una faggeta a 1100 m s.l.m. In entrambi i casi l?areale della specie è risultato parapatrico con quello di <em>Talpa europaeaem>.
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Xuemei Liu
2012-09-01
Full Text Available Cellulose synthase (CESA, which is an essential catalyst for the generation of plant cell wall biomass, is mainly encoded by the <em>CesA> gene family that contains ten or more members. In this study; four full-length cDNAs encoding CESA were isolated from<em> Betula platyphyllaem> Suk., which is an important timber species, using RT-PCR combined with the RACE method and were named as <em>BplCesA3em>, <em>−4em>,
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José Gabriel Segarra-Moragues
2012-09-01
Full Text Available Polymorphic microsatellite markers were developed for the Ibero-North African, strict gypsophyte <em>Lepidium subulatumem> to unravel the effects of habitat fragmentation in levels of genetic diversity, genetic structure and gene flow among its populations. Using 454 pyrosequencing 12 microsatellite loci including di- and tri-nucleotide repeats were characterized in <em>L. subulatumem>. They amplified a total of 80 alleles (2–12 alleles per locus in a sample of 35 individuals of <em>L. subulatumem>, showing relatively high levels of genetic diversity, <em>H>O = 0.645, <em>H>E = 0.627. Cross-species transferability of all 12 loci was successful for the Iberian endemics <em>Lepidium cardaminesem>, <em>Lepidium stylatumem>, and the widespread, <em>Lepidium graminifoliumem> and one species each of two related genera, <em>Cardaria drabaem> and <em>Coronopus didymusem>. These microsatellite primers will be useful to investigate genetic diversity, population structure and to address conservation genetics in species of <em>Lepidium>.
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Constituents from <em>Vigna em>vexillata> and Their Anti-Inflammatory Activity
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Guo-Feng Chen
2012-08-01
Full Text Available The seeds of <em>Vigna em>genus are important food resources and there have already been many reports regarding their bioactivities. In our preliminary bioassay, the chloroform layer of methanol extracts of<em> V. vexillata em>demonstrated significant anti-inflammatory bioactivity. Therefore, the present research is aimed to purify and identify the anti-inflammatory principles of <em>V. vexillataem>. One new sterol (1 and two new isoflavones (2,3 were reported from the natural sources for the first time and their chemical structures were determined by the spectroscopic and mass spectrometric analyses. In addition, 37 known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature. Among the isolates, daidzein (23, abscisic acid (25, and quercetin (40 displayed the most significant inhibition of superoxide anion generation and elastase release.
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Xishi Tai
2012-09-01
Full Text Available A new trinuclear Cd (II complex [Cd3(L6(2,2-bipyridine3] [L =<em> Nem>-phenylsulfonyl-L>-leucinato] has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction analysis. The results show that the complex belongs to the orthorhombic, space group<em> Pem>212121 with<em> aem> = 16.877(3 Å, <em>b
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Song Yang
2012-08-01
Full Text Available A series of <em>N>-substituted 5-chloro-6-phenylpyridazin-3(2<em>H>-one derivatives were synthesized based on our previous work; all compounds were characterized by spectral data and tested for <em>in vitroem> insecticidal activity against <em>Plutella xylostellaem>. The results showed that the synthesized pyridazin-3(2<em>H>-one compounds possessed good insecticidal activities, especially the compounds 4b, 4d, and 4h which showed > 90% activity at 100 mg/L. The structure-activity relationships (SAR for these compounds were also discussed.
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Laser welding of tailored blanks
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Peças, P.
1998-04-01
Full Text Available Laser welding has an incrising role in the automotive industry, namely on the sub-assemblies manufacturing. Several sheet-shape parts are laser welded, on a dissimilar combination of thicknesses and materials, and are afterwards formed (stamped being transformed in a vehicle body component. In this paper low carbon CO2 laser welding, on the thicknesses of 1,25 and 0,75 mm, formability investigation is described. There will be a description of how the laser welded blanks behave in different forming tests, and the influence of misalignment and undercut on the formibility. The quality is evaluated by measuring the limit strain and limit effective strain for the laser welded sheets and the base material, which will be presented in a forming limit diagram.
A soldadura laser assume um papel cada vez mais importante na indústria automóvel, principalmente para a fabricação de sub-conjuntos constituídos por varias partes de chapa de diferentes espessuras (e diferentes materiais, que depois de estampados constituem um componente para integrar num veículo. Descreve-se neste artigo o trabalho de investigação de enformabilidade de chapa de ac.o de baixo carbono soldada por laser de CO2, nas espessuras de 1,25 e 0,75 mm. Apresenta-se uma descrição do comportamento das chapas soldadas por laser em diferentes testes de enformação, e a influência dos defeitos das soldaduras (desalinhamento e queda do banho-undercut no comportamento à enformação. A qualidade é avaliada pela medição da extensão limite e da extensão limite efectiva no material base e no material soldado, que serão representadas num diagrama de limite de enformabilidade. -
Produção de PCB recorrendo a tecnologia Laser
Soares, Rodolfo da Silva
2011-01-01
O elevado nível de integração e miniaturização dos componentes existente nos dias de hoje, criam novos desafios na concepção de circuitos impressos. Neste trabalho são apresentados métodos para interligação entre componentes, em circuitos impressos com elevado número de ligações, recorrendo a tecnologia laser. Foi desenvolvida uma máquina CNC de três eixos, para posicionamento de um laser, mantendo o suporte para as operações tradicionais com ferramentas. O sistema foi concebid...
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Edélcio Vieira
2004-12-01
Full Text Available OBJETIVO: Descrever a técnica da retirada de sutura em córnea clara, evitando-se o contato da parte externa do fio com o meio intra-ocular e avaliar se esse procedimento evitaria infecções. MÉTODOS: Foi realizado estudo retrospectivo de 1.233 casos de retirada de sutura de mononylon 10.0 em córnea clara, utilizando-se laser de argônio para cortar o fio, no qual se avaliou a incidência de infecções. RESULTADOS: Em 1.071 olhos, um tiro foi suficiente para cortar o ponto. Em 162 olhos, o tiro do laser atingiu a parte epitelial da sutura, sendo necessários disparos extras para cortar a parte intra-estromal e, assim, retirá-la sem que a parte externa do fio passasse pelo interior da córnea. Não ocorreram complicações após a retirada da sutura. CONCLUSÕES: A técnica utilizada mostrou-se eficaz na remoção das suturas e possivelmente apresenta risco menor de infecção, uma vez que a parte do fio sobrejacente ao epitélio não entra em contato com as camadas mais internas da córnea, nem com a câmara anterior, não tendo sido observado nenhum caso de infecção nesta pesquisa.PURPOSE: To describe the technique of clear-cornea suture removal, that avoids the contact of the external part of the thread with the intraocular medium, and to evaluate whether this procedure would prevent infections. METHODS: A retrospective study of 1.233 cases of clear-cornea mononylon 10.0 suture removal, by the use of an argon laser to cut the thread, was performed. Incidence of infection was then assessed. RESULTS: In 1.071 eyes, one shot was enough to cut the stitch. In 162 eyes, the laser shot hit the epithelial part of the suture, making new shots necessary to cut the intrastromal part, and thus to remove it assuring that the outer part of the stitch would not come in to contact with the interior of the cornea. There were no complications after suture removal. CONCLUSIONS: The technique has shown to be effective in suture removal. And, possibly
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Guy Hamelin
2011-09-01
Full Text Available Na sua obra, Pedro Abelardo (1079-1142 destaca duas noções metafísicas que fundamentam sua teoria lógica: o <em style="mso-bidi-font-style: normal;">statusem> e o <em style="mso-bidi-font-style: normal;">dictum propositionisem>, ao causar, respectivamente, a imposição (<em style="mso-bidi-font-style: normal;">impositioem> dos termos universais e o valor de verdade das proposições. Trata-se de expressões que se referem a naturezas ontológicas peculiares, na medida em que não são consideradas coisas (<em style="mso-bidi-font-style: normal;">resem>, mesmo que constituem causas. Todavia, também não são nada. Abelardo as chama de ‘quase coisas’ (<em style="mso-bidi-font-style: normal;">quasi resem>. No presente artigo, explicamos, primeiro, essas duas noções essenciais da lógica abelardiana, antes de tentar, em seguida, encontrar a fonte dessa metafísica particular. Em oposição a comentadores importantes da lógica de Abelardo, que estimam que haja uma forte influência platônica sobre essa concepção específica, defendemos antes, com apoio de textos significativos e de acordo com o nominalismo abelardiano, que a maior ascendência sobre a metafísica do nosso autor é a do estoicismo, sobretudo, antigo.In his work, Peter Abelard (1079-1142 highlights two metaphysical notions, which sustain his logical theory: the <em>status> and the <em>dictum propositionisem>, causing respectively both the imposition (<em>impositio> of universal terms and the thuth-value of propositions. Both expressions refer to peculiar ontological natures, in so far as they are not considered things (<em>res>, even if they constitute causes. Nevertheless, neither are they ‘nothing’. Abelard calls them ‘quasi-things’ (<em>quasi resem>. In the present article, we expound first these two essential notions of Abelardian logic before then trying to find the source of this particular metaphysics. Contrary to some important
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Lúcia de Noronha
2004-06-01
Full Text Available O uso do laser neodymium-yttrium-aluminium-garnet (Nd-YAG como instrumento auxiliar para o rejuvenescimento propiciou um refinamento da técnica tradicional. Tal procedimento mostra resultados satisfatórios com relação ao aprimoramento técnico e à recuperação pós-operatória. OBJETIVO: Evidenciar as alterações histológicas e morfométricas encontradas na pálpebra de humanos após aplicação do laser Nd-YAG e comparar com a pele normal. MATERIAL E MÉTODO: Nove pacientes do sexo feminino foram submetidas à aplicação do laser Nd-YAG em região palpebral direita. A pálpebra esquerda correspondeu à área controle, livre de qualquer tipo de procedimento. Foram realizadas várias aplicações do laser Nd-YAG, sendo que, no último dia, foi realizada biópsia palpebral bilateralmente. Os critérios morfométricos avaliados foram: medida da espessura da epiderme, da área subepidérmica livre de lesão, da zona de degeneração do colágeno e da espessura total da derme. RESULTADOS: Nas áreas submetidas à aplicação do laser Nd-YAG, a espessura média da epiderme foi de 33,53 micrômetros (µm e a da pele normal foi de 29,61µm (p = 0,1099. A média da medida da área subepidérmica livre de lesão, no lado direito, foi de 40,93µm, e de 36,27µm (p = 0,1373 no esquerdo. A espessura da região de degeneração do colágeno na pálpebra que recebeu tratamento com laser teve média de 293,54µm, enquanto que na pálpebra normal ela foi de 292,22µm (p = 0,4835. No lado onde se aplicou o laser Nd-YAG, a espessura total da derme teve uma média de 681,48µm e, no lado livre de procedimento, 664,14µm (p = 0,3492. DISCUSSÃO E CONCLUSÕES: Apesar da diferença clínica observada após tratamento de lesões de envelhecimento em pálpebra de humanos com o uso do laser Nd-YAG, nota-se que não houve diferença histológica ou morfométrica após tal procedimento.The use of laser Neodymium-Yttrium-Aluminium-Garnet (Nd-YAG as an auxiliary
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Lênio Souza Alvarenga
1999-12-01
Full Text Available Objetivo: Estudar a influência do equivalente esférico nos valores obtidos pelo GDX TM Scanning Laser System®. Métodos: Foram avaliados 41 olhos de 41 voluntários sem doenças oculares e com campo visual sem alterações. Foi realizada a polarimetria de varredura a laser com o GDX TM Scanning Laser System® de acordo com as instruções contidas no manual do aparelho. Foram comparados os valores obtidos nesse exame em um grupo de pacientes com equivalente esférico positivo e em um outro com este valor nulo ou negativo, pelo teste de Mann-Whitney. Resultados: Não se verificou diferença estatística entre os valores obtidos nos olhos de pacientes do grupo I e os do grupo II. Não foi encontrada correlação entre o equivalente esférico e os valores obtidos com o GDX TM Scanning Laser System®. Conclusões: Na amostra estudada não houve diferença estatística entre os valores obtidos em um grupo de olhos com equivalente esférico positivo e outro com este valor negativo ou nulo, usando-se o GDX TM Scanning Laser System®.Purpose: To evaluate the effect of spherical equivalent on the acquisition of nerve fiber layer (NFL thickness with GDX TM Scanning Laser System®. Methods: Forty-one eyes of 41 volunteers were enrolled in this study. All of them presented with no ocular disease and no visual field defect. The NFL thickness was measured with GDX TM Scanning Laser System® as described in its manual. The values obtained in a group of volunteers with negative spherical equivalent (group I were compared to those from a group with a positive spherical equivalent (group II by the Mann-Whitney test. Results: There was no statistical difference between mea-surements in eyes of group I and those in group II. The NFL thickness measurements were not correlated with the sphe-rical equivalent. Conclusions: In the studied group there was no statistical difference in the GDX TM Scanning Laser System® parameters related to spherical equivalent.
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JC Frare
2008-02-01
Full Text Available INTRODUÇÃO: Nos últimos anos, tem sido notado grande interesse no estudo de novas modalidades para o tratamento das disfunções temporomandibulares (DTM. A dor descrita como dor facial, cefaléia ou dor de ouvido, comumente exacerbada pela função da mandíbula, é, em geral, a principal queixa do paciente. A fotobiomodulação laser vem sendo utilizada no tratamento da dor em DTM. OBJETIVO: O objetivo deste estudo foi verificar o nível de dor de pacientes com DTM tratados com fotobiomodulação laser. MATERIAIS E MÉTODOS: Foram estudados 18 pacientes do sexo feminino, com idade média de 27 anos (± 7, com diagnóstico de DTM, os quais foram separados aleatoriamente em dois grupos: Placebo (Controle e Tratado. O Grupo Tratado (n= 10 recebeu atendimento duas vezes por semana, por quatro semanas consecutivas (totalizando oito aplicações. Utilizou-se o laser de GaAs (904 nm, 6 J/cm², 0,38 mW/cm², área do feixe de 0,039 cm², com modo de emissão contínua. Realizou-se a aplicação do laser em quatro pontos pré-auriculares e um em meato acústico externo. O Grupo Placebo (n= 8 foi manipulado como o tratado, porém com o laser desligado. Para análise do nível de dor dos pacientes, empregou-se a Escala Visual Analógica (EVA de dor, antes e após a terapia. Para a análise dos dados, empregou-se o teste t de Student, com nível de significância de 5% (pINTRODUCTION: Over the last few years, there has been great interest in studying new methods for treating temporomandibular joint dysfunction (TMD. Pain, described as facial pain, headache or earache, usually exacerbated by jaw use, is generally the patients' main complaint. Laser photobiomodulation has been used for treating pain in cases of TMD. OBJECTIVE: The aim of this study was to investigate the pain levels in TMD patients treated with laser photobiomodulation. MATERIAL AND METHODS: Eighteen female patients of mean age was 27 years (± 7, with a diagnosis of TMD, were studied
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Conxita Avila
2012-08-01
Full Text Available Ascidians have developed multiple defensive strategies mostly related to physical, nutritional or chemical properties of the tunic. One of such is chemical defense based on secondary metabolites. We analyzed a series of colonial Antarctic ascidians from deep-water collections belonging to the genera <em>Aplidium> and <em>Synoicum> to evaluate the incidence of organic deterrents and their variability. The ether fractions from 15 samples including specimens of the species <em>A.> <em>falklandicum>, <em>A.> <em>fuegiense>, <em>A.> <em>meridianum>, <em>A.> <em>millari> and <em>S.> <em>adareanum> were subjected to feeding assays towards two relevant sympatric predators: the starfish <em>Odontaster> <em>validus>, and the amphipod <em>Cheirimedon> <em>femoratus>. All samples revealed repellency. Nonetheless, some colonies concentrated defensive chemicals in internal body-regions rather than in the tunic. Four ascidian-derived meroterpenoids, rossinones B and the three derivatives 2,3-epoxy-rossinone B, 3-epi-rossinone B, 5,6-epoxy-rossinone B, and the indole alkaloids meridianins A–G, along with other minoritary meridianin compounds were isolated from several samples. Some purified metabolites were tested in feeding assays exhibiting potent unpalatabilities, thus revealing their role in predation avoidance. Ascidian extracts and purified compound-fractions were further assessed in antibacterial tests against a marine Antarctic bacterium. Only the meridianins showed inhibition activity, demonstrating a multifunctional defensive role. According to their occurrence in nature and within our colonial specimens, the possible origin of both types of metabolites is discussed.
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Luisa Quintino
2012-09-01
Full Text Available The demand of emerging joining techniques for shape memory alloys (SMA has become of great importance, as their functional properties namely shape memory effect (SME and superelasticity (SE present unique solutions for state-of-the-art applications. Welding of SMAs is a challenge due to the risk of reduced mechanical performance after laser processing. The wider application of these alloys in various sectors as aerospace, medical or electronic industry is hindered by the limitations in its processing. The need to weld SMAs to other materials is pressing for applications in the above referred sectors. In dissimilar joints the need to understand materials behavior is even more challenging since base materials have different physical properties leading to different heat flow, convection processes and residual stress distribution. The chemical composition across the weld pool varies and intermetallic compounds are formed. Research detailing the effects of laser processing on NiTi is essential to overcome many of these challenges. The objectives of the current study are to analyze the effects of laser welding in the weld shape of both similar and dissimilar joints of NiTi to stainless steel and titanium alloys.A procura de técnicas de ligação para ligas de memória de forma tem-se revetido de importância crescente, devido ao desenvolvimento de aplicações deste material com particulares propriedades de memória de forma e superelasticidade. A soldadura de ligas de memória de forma é um desafio devido ao risco de emporbrecimento das propriedades mecânicas depois do processamento laser. A aplicação alargarda destas ligas em vários sectores como o aeroespacial, medico ou electrónico é prejudicado pelas limitações de processamento. A necessidade de soldar ligas de memória de forma a outros materiais é premente para estes sectores. Em juntas dissimilares, o entendimento do comportamento dos materaias é um desafio ainda maior uma vez que
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Multifunctional Material Structures Based on Laser-Etched Carbon Nanotube Arrays
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Aline Emplit
2014-09-01
Full Text Available High-power electronics in the transportation and aerospace sectors need size and weight reduction. Multifunctional and multistructured materials are currently being developed to couple electromagnetic (EM and thermal properties, i.e., shielding against electromagnetic impulsions, and thermal management across the thermal interface material (TIM. In this work, we investigate laser-machined patterned carbon nanotube (CNT micro-brushes as an alternative to metallic structures for driving simultaneously EM and heat propagation. The thermal and electromagnetic response of the CNT array is expected to be sensitive to the micro-structured pattern etched in the CNT brush.
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Il-Kwon Park
2012-09-01
Full Text Available Commercial plant essential oils obtained from 11 Myrtaceae plant species were tested for their fumigant antifungal activity against <em>Aspergillus ochraceusem>, <em>A. flavusem>, and <em>A. nigerem>. Essential oils extracted from<em> em>Leptospermum> <em>petersonii> at air concentrations of 56 × 10−3 mg/mL and 28 × 10−3 mg/mL completely inhibited the growth of the three <em>Aspergillus> species. However, at an air concentration of 14 × 10−3 mg/mL, inhibition rates of <em>L. petersoniiem> essential oils were reduced to 20.2% and 18.8% in the case of <em>A. flavusem> and <em>A. nigerem>, respectively. The other Myrtaceae essential oils (56 × 10−3 mg/mL only weakly inhibited the fungi or had no detectable affect. Gas chromatography-mass spectrometry analysis identified 16 compounds in <em>L. petersoniiem>
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Adilvania Ferreira da Costa
2012-08-01
Full Text Available The objective of the present study was to perform an in vitro evaluation of the bactericidal action of a low-power arsenium-gallium (AsGa laser at a wavelength of 904nm and energy density of 6 J/cm². Ten petri dishes were seeded with Pseudomonas aeruginosa and another ten with Staphylococcus aureus. The dishes were then randomly divided into four groups with five plates in each group. Two groups were treated with AsGa laser once a day for 5 days, while the other two groups received no treatment. No halo of growth inhibition was found in any of the groups. It was therefore concluded that laser treatment (AsGa, 904nm, 6J/cm² had no bactericidal effect.Verificar, in vitro, o efeito bactericida do laser de baixa potência, AsGa, 904nm, na dose 6 J/cm2. Foram semeadas 10 placas de Petri com a bactéria Pseudomonas aeruginosa e 10 placas de Petri com Staphylococcus aureus. Aleatoriamente, foram divididas em quatro grupos (5 placas cada: dois grupos foram tratados com o laser AsGa a cada 24 horas, durante cinco dias, e dois grupos não receberam tratamento. Em todos os grupos, não foi observado qualquer halo de inibição do crescimento. Assim, concluiuse que a terapia a laser (AsGa, 904nm, 6 J/cm² não produziu efeito bactericida.
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Günther K. Bonn
2012-07-01
Full Text Available This study was designed to investigate the DNA-methylation status of <em>E>-cadherin (<em>CDH1em> and <em>H>-cadherin (<em>CDH13em> in serum samples of cervical cancer patients and control patients with no malignant diseases and to evaluate the clinical utility of these markers. DNA-methylation status of <em>CDH1em> and <em>CDH13em> was analyzed by means of MethyLight-technology in serum samples from 49 cervical cancer patients and 40 patients with diseases other than cancer. To compare this methylation analysis with another technique, we analyzed the samples with a denaturing high performance liquid chromatography (DHPLC PCR-method. The specificity and sensitivity of <em>CDH1em> DNA-methylation measured by MethyLight was 75% and 55%, and for <em>CDH13em> DNA-methylation 95% and 10%. We identified a specificity of 92.5% and a sensitivity of only 27% for the <em>CDH1em> DHPLC-PCR analysis. Multivariate analysis showed that serum <em>CDH1em> methylation-positive patients had a 7.8-fold risk for death (95% CI: 2.2–27.7; <em>p> = 0.001 and a 92.8-fold risk for relapse (95% CI: 3.9–2207.1; <em>p> = 0.005. We concluded that the serological detection of <em>CDH1em> and <em>CDH13em> DNA-hypermethylation is not an ideal diagnostic tool due to low diagnostic specificity and sensitivity. However, it was validated that <em>CDH1em> methylation analysis in serum samples may be of potential use as a prognostic marker for cervical cancer patients.
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Conz, Roberto [UNESP
2004-01-01
O objetivo deste trabalho foi substituir um bloco de grandes dimensões em aço forjado, por chapas finas de aço, laminadas a quente, soldadas pelo processo LASER CO2, destinadas à fabricação de rotores para máquinas elétricas com até 40 MW de potência, para tanto foram utilizadas chapas com 3 mm de espessura, empilhadas, compactadas e fixadas por tirantes. Considerando que a largura das bobinas e blanks disponíveis no mercado nacional não atendem às necessidades dimensionais do produto fez-se ...
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Generalização de modelos digitais de terreno com base em transformada wavelet
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Clovis Gaboardi
Full Text Available Os sistemas de laser scanner permitem a obtenção de modelos digitais de terreno de alta resolução e exatidão. Porém, quando se necessita trabalhar em aplicações com uma resolução menor que a originalmente gerada, a grande quantidade de dados acarreta a necessidade de generalização. Este trabalho tem por objetivo verificar o comportamento da transformada wavelet na generalização de modelos digitais do terreno sob a forma de grades regulares, obtidas a partir de dados do laser scanner. As transformadas wavelets foram implementadas em programas na linguagem Matlab. Foram utilizadas as wavelets de Haar, Daubechies e Symlet. A generalização por krigagem foi utilizada para a comparação dos resultados. Os resultados obtidos nos experimentos realizados permitem afirmar que a transformada wavelet pode ser utilizada como alternativa para a generalização de MDT em razão da facilidade de programação, baixo custo computacional, alta velocidade de processamento e exatidão compatível com a resolução obtida no MDT generalizado, além de ser um método natural de análise multirresolução.
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Yuangang Zu
2012-07-01
Full Text Available An ultrasound and microwave assisted alternant extraction method (UMAE was applied for extracting dihydroquercetin (DHQ from <em>Larix gmeliniem>i> wood. This investigation was conducted using 60% ethanol as solvent, 1:12 solid to liquid ratio, and 3 h soaking time. The optimum treatment time was ultrasound 40 min, microwave 20 min, respectively, and the extraction was performed once. Under the optimized conditions, satisfactory extraction yield of the target analyte was obtained. Relative to ultrasound-assisted or microwave-assisted method, the proposed approach provides higher extraction yield. The effect of DHQ of different concentrations and synthetic antioxidants on oxidative stability in soy bean oil stored for 20 days at different temperatures (25 °C and 60 °C was compared. DHQ was more effective in restraining soy bean oil oxidation, and a dose-response relationship was observed. The antioxidant activity of DHQ was a little stronger than that of BHA and BHT. Soy bean oil supplemented with 0.08 mg/g DHQ exhibited favorable antioxidant effects and is preferable for effectively avoiding oxidation. The <em>L. gmeliniiem> wood samples before and after extraction were characterized by scanning electron microscopy. The results showed that the UMAE method is a simple and efficient technique for sample preparation.
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Eduardo Alonso Garcia
2009-08-01
Full Text Available OBJETIVO: Analisar as complicações da aplicação do laser de diodo para o tratamento da obstrução nasolacrimal adquirida. MÉTODOS: Foram realizados 44 procedimentos (dacriocistorrinostomia transcanalicular com laser de diodo com intubação bicanalicular de silicone sob anestesia local entre fevereiro de 2002 a novembro de 2007 em 41 pacientes (3 bilateralmente, sendo 32 mulheres e 9 homens. RESULTADOS: As complicações mais frequentes no intraoperatório foram: dificuldade de passar a sonda de Crawford (13,6% e passagem da fibra óptica dificultada (11,3%. No pós-operatório, a epífora foi a ocorrência mais frequente (15,9%, seguida pela retirada acidental do silastic (11,3%. CONCLUSÃO: Os índices de complicações intra e pós-operatórias se equivalem aos artigos publicados com a mesma técnica cirúrgica (e mesmo tipo de laser.PURPOSE: To evaluate the complications of the use of diode laser in the treatment of acquired nasolacrimal obstruction. METHODS: Forty four procedures (transcanalicular dacryocystorhinostomy with diode laser with bicanalicular silicone tube intubation and local anesthesia where performed from February 2002 to November 2007 in 41 patients (3 bilaterally, 32 women and 9 men. RESULTS: The most common intraoperative complications were disability to pass the Crawford probe (13.6% and the laser probe (11.3%. Regarding postoperative complications, epiphora was the event of higher frequency (15.9% followed by the non-intentional silastic extrusion by the patient (11.3%. CONCLUSION: Intraoperative and postoperative complications rate were similar of others articles that demonstrated the same surgical technique (with same laser.
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Katherine A. Aronstein
2012-06-01
Full Text Available We investigated the effect of the parasitic mite <em>Varroa destructorem> on the immunological and nutritional condition of honey bees, <em>Apis melliferaem>, from the perspective of the individual bee and the colony. Pupae, newly-emerged adults and foraging adults were sampled from honey bee colonies at one site in S. Texas, USA. <em>Varroa>‑infested bees displayed elevated titer of Deformed Wing Virus (DWV, suggestive of depressed capacity to limit viral replication. Expression of genes coding three anti-microbial peptides (<em>defensin1, abaecin, hymenoptaecinem> was either not significantly different between <em>Varroa>-infested and uninfested bees or was significantly elevated in <em>Varroa>-infested bees, varying with sampling date and bee developmental age. The effect of <em>Varroa> on nutritional indices of the bees was complex, with protein, triglyceride, glycogen and sugar levels strongly influenced by life-stage of the bee and individual colony. Protein content was depressed and free amino acid content elevated in <em>Varroa>-infested pupae, suggesting that protein synthesis, and consequently growth, may be limited in these insects. No simple relationship between the values of nutritional and immune-related indices was observed, and colony-scale effects were indicated by the reduced weight of pupae in colonies with high <em>Varroa> abundance, irrespective of whether the individual pupa bore <em>Varroa>.
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Gladson Ricardo Flor Bertolini
2009-08-01
Full Text Available Durante o processo inflamatório, alguns tipos de células predominam e estão envolvidos com a produção de dor. O laser de baixa potência mostra-se útil no controle de mediadores inflamatórios, mas a ampla divergência nos parâmetros dosimétricos, conduz a variações nos resultados positivos. O objetivo deste estudo foi analisar o uso do laser 808nm, na dor articular crônica e edema de ratos Wistar submetidos a sinovite. Foram utilizados 10 ratos Wistar, divididos em dois grupos: GC - indução de sinovite em joelho direito e tratamento placebo; GT - indução de sinovite e irradiado com laser 10J/cm². Para a produção de sinovite foram injetados 100µl de formalina a 5%, no espaço articular tibiofemoral direito. A avaliação da dor ocorreu pelo tempo de elevação da pata (TEP. No 10º dia após a indução de sinovite, iniciou-se o tratamento com laser sobre a face articular medial do joelho, procedimento mantido no decorrer de 10 dias. Os resultados mostraram que o laser apresentou efeitos analgésicos, visto que, para o grupo tratado, houve redução significativa nos valores de TEP, indicando redução da dor, quando comparados os valores pós-tratamento com os pré-tratamento, o que não ocorreu para o grupo que recebeu tratamento placebo; para o edema, o laser também mostrou redução significativa do mesmo. Concluiu-se que o laser 808nm, com 10J/cm², é eficaz na redução da dor articular crônica e edema, em animais submetidos a sinovite experimental.During the inflammatory process some kinds of cells are predominant and are involved with pain production. Low power laser seems to be useful in the control of inflammatory mediators, but wide divergence in the dosemetric parameters leads to variations in its positive results. The aim of this study was to assess the use of the 808nm laser in the chronic joint pain and edema of Wistar rats submitted to synovitis. Sample was composed of 10 Wistar rats divided in two groups
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Lidke, D.S.; Nagy, P.; Barisas, B.G.; Heintzmann, R.; Post, Janine Nicole; Lidke, K.A.; Clayton, A.H.A.; Arndt-jovin, D.J.; Jovin, T.M.
2003-01-01
We report the implementation and exploitation of fluorescence polarization measurements, in the form of anisotropy fluorescence lifetime imaging microscopy (rFLIM) and energy migration Förster resonance energy transfer (emFRET) modalities, for wide-field, confocal laser-scanning microscopy and flow
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Longino Contoli
1986-12-01
Full Text Available Abstract In small Mammals biogeography, available data are up to now by far too scanty for elucidate the distribution of a lot of taxa, especially with regard to the absence from a given area. In this respect, standardized quantitative sampling techniques, like Owl pellets analysis can enable not only to enhance faunistic knowledges, but also to estimate the actual absence probability of a given taxon "m", lacking from the diet of an individual raptor. For the last purpose, the relevant frequencies of "m" in the other ecologically similar sites of the same raptor species diets are averaged ($f_m$ : the relevant standard error (multiplicated by a coefficient, according to the desired degree of accuracy, in relation of the integral of probabilities subtracted ($overline{F}_m - a E$: then, the probability that a single specimen is not pertaining to "m" is obtained ($P_0 = 1 - F_m + a E$; lastly, the desiderate accuracy probability ($P_d$ is chosen. Now, "$N_d$" (the number of individuals of all prey species in a single site needed for obtain, with the desired probability, a specimen at least of "m" is obtained through $$N = frac{ln P_d}{ln P_0}$$ Obviously, every site-diet with more than "N" preyed individuals and without any "i" specimen is considered to be lacking of such taxon. A "usefulness index" for the above purposes is outlined and checked about three raptors. Some exanples about usefulness of the Owl pellet analysis method in biogeography are given, concerning <em>Tyto albaem> diets in peninsular Italy about: - <em>Sorex minutusem>, lacking in some quite insulated areas; - <em>Sorex araneusem> (sensu stricto, after GRAF et al., 1979, present also in lowland areas in Emilia-Romagna; - <em>Crocidura suaveolensem> and - <em>Suncus etruscusem>, present also in the southermost part of Calabria (Reggio province; - <em>Talpa caecaem>, present also in the Antiapennines of Latium (Cimini mounts; - <em>Talpa romanaem
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Análise metalográfica do titânio puro submetido à soldagem laser Nd: YAG e TIG
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Ana Cláudia Gabrielli Piveta
Full Text Available INTRODUÇÃO: Os métodos de soldagem mais utilizados em Odontologia não podem ser aplicados ao titânio puro e às suas ligas em função da alta reatividade do titânio com elementos atmosféricos; dessa forma, o mesmo não deve ser soldado por processo comum. OBJETIVO: O objetivo deste trabalho foi avaliar a característica metalúrgica do titânio comercialmente puro sem solda e submetido aos processos de soldagem a laser e TIG. MATERIAL E MÉTODO: Foram confeccionados 15 corpos de prova em titânio comercialmente puro, cinco para cada condição, na forma de hastes cilíndricas, obtidas por fundição odontológica, sob atmosfera de gás argônio e vácuo, com calor produzido por um arco voltaico, com a injeção do titânio sob vácuo-pressão. Três grupos foram formados I: soldagem a laser; II: soldagem TIG, e III: sem solda. Os corpos de prova do grupo I e II foram seccionados ao meio e soldados por TIG e por laser, respectivamente; o grupo III foi mantido sem corte e sem solda, como controle. A análise metalográfica foi realizada sob aumentos de 50×, 100× e 200×, em microscópio. RESULTADO: Pelos resultados obtidos nas micrografias, o titânio comercialmente puro apresentou uma morfologia de grãos equiaxiais da fase α, o cordão de solda a laser apresentou estrutura martensítica e, na TIG, microestrutura Widmanstätten. CONCLUSÃO: A microestrutura martensítica é condizente com a alta taxa de resfriamento proveniente do processo de soldagem a laser. As estruturas martensítica e Widmansttäten são mais refinadas quando comparadas à microestrutura do metal base.
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Energy Technology Data Exchange (ETDEWEB)
Ahmed, H. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Kar, S., E-mail: s.kar@qub.ac.uk [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Cantono, G. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Department of Physics “E. Fermi”, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica, Research Unit Adriano Gozzini, via G. Moruzzi 1, Pisa 56124 (Italy); Nersisyan, G. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Brauckmann, S. [Institut für Laser-und Plasmaphysik, Heinrich-Heine-Universität, Düsseldorf (Germany); Doria, D.; Gwynne, D. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Macchi, A. [Department of Physics “E. Fermi”, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica, Research Unit Adriano Gozzini, via G. Moruzzi 1, Pisa 56124 (Italy); Naughton, K. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Willi, O. [Institut für Laser-und Plasmaphysik, Heinrich-Heine-Universität, Düsseldorf (Germany); Lewis, C.L.S.; Borghesi, M. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom)
2016-09-01
The divergent and broadband proton beams produced by the target normal sheath acceleration mechanism provide the unique opportunity to probe, in a point-projection imaging scheme, the dynamics of the transient electric and magnetic fields produced during laser-plasma interactions. Commonly such experimental setup entails two intense laser beams, where the interaction produced by one beam is probed with the protons produced by the second. We present here experimental studies of the ultra-fast charge dynamics along a wire connected to laser irradiated target carried out by employing a ‘self’ proton probing arrangement – i.e. by connecting the wire to the target generating the probe protons. The experimental data shows that an electromagnetic pulse carrying a significant amount of charge is launched along the wire, which travels as a unified pulse of 10s of ps duration with a velocity close to speed of light. The experimental capabilities and the analysis procedure of this specific type of proton probing technique are discussed. - Highlights: • Prompt charging of laser irradiated target generates ultra-short EM pulses. • Its ultrafast propagation along a wire was studied by self-proton probing technique. • Self-proton probing technique is the proton probing with one laser pulse. • Pulse temporal profile and speed along the wire were measured with high resolution.
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Directory of Open Access Journals (Sweden)
Moisés P. Silva
2011-02-01
Full Text Available BACKGROND: Low level laser therapy (LLLT has been used clinically in order to treat inflammation, where tissue and plasma prekallikrein have crucial importance. Plasma prekallikrein (PPK is synthesized by the hepatocytes and secreted into the bloodstream, where it participates in the surface-dependent activation of blood coagulation, fibrinolysis, kinin generation and inflammation. Tissue prekallikrein is associated with important disease states (including cancer, inflammation, and neurodegeneration and has been utilized or proposed as clinically important biomarker or therapeutic target of interest. OBJECTIVE: To evaluate if LLLT modulates tissue and plasma prekallikreins mRNA expression in the carrageenan-induced rat paw edema. METHODS: Experimental groups were assigned as followed: A1 (Control-saline, A2 (Carrageenan-only, A3 (laser 660nm only and A4 (Carrageenan + laser 660nm. Edema was measured by a plethysmometer. Subplantar tissue was collected for the quantification of prekallikreins mRNA by Real time-Polymerase Chain Reaction. RESULTS: A significantly decrease in the edema was observed after laser irradiation. Expression of prekallikreins increased after carrageenan injection. Tissue and plasma prekallikrein mRNA expression significantly decreased after LLLT's 660nm wavelength. CONCLUSION: These results suggest that expression of tissue and plasma prekallikreins is modulated by LLLT, which can be used in clinical practice due to its anti-inflammatory effects.CONTEXTUALIZAÇÃO: A laserterapia de baixa potência tem sido usada para o tratamento de processos inflamatórios diversos em que a calicreína tecidual e a plasmática possuem participação ativa. A pré-calicreína plasmática (PPK é sintetizada pelos hepatócitos e secretada na corrente sanguínea, onde participa da ativação da coagulação, fibrinólise, geração de cininas e inflamação. A pré-calicreína tecidual está associada com importantes doenças (incluindo c
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O uso do laser na reabilitação das desordens temporomandibulares
Directory of Open Access Journals (Sweden)
Thiago de Oliveira Assis
Full Text Available INTRODUÇÃO: Entende-se disfunção temporomandibular comoum termo coletivo que envolve um grande número de problemas clínicos que afetam os músculos mastigatórios, a articulação temporomandibular (ATM e estruturas associadas. Dentre os principais sinais e sintomas, incluem-se dores nos músculos da mastigação ou na ATM, ruídos articulares, limitação de abertura, retração gengival, oclusão inadequada, distúrbios auditivos, cefaleias, sensibilidade em toda a musculatura do sistema estomatognático e cervical. OBJETIVOS: Estudar a influência da laserterapia de baixa intensidade (diodo no tratamento das desordens temporomandibulares. MATERIAIS E MÉTODOS: Trata-se de uma revisão sistemática. Foram consultadas as seguintes bases de dados: BIREME, MEDLINE, PubMed, Science Direct e LILACS. Os termos de busca utilizados foram "temporomandibular laser therapy" e "ATM laser treatment", em inglês e português. Não foram estabelecidos limites de busca. Após a busca independente de dois revisores, foram encontrados 1.344 artigos e, após a aplicação dos critérios de exclusão, 12 artigos foram selecionados para a análise. RESULTADOS: Dos 12 artigos selecionados, apenas em 1 (um deles não foi verificada qualquer melhora do quadro doloroso na ATM em virtude dos diversos tipos de DTM. CONCLUSÃO: Apesar dos resultados satisfatórios do uso do laser na redução sintomática da dor nos DTM, ainda é controversa a utilização dos seus parâmetros para cada caso. Por isso, sugerimos a realização de outros estudos para que essas lacunas sejam preenchidas com o objetivo maior de promover uma melhor qualidade de vida para as pessoas que sofrem quaisquer transtornos na região da ATM.
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Directory of Open Access Journals (Sweden)
Maznah Ismail
2012-09-01
Full Text Available This study presents the proximate and mineral composition of <em>Peperomia> <em>pellucida> L., an underexploited weed plant in Malaysia. Proximate analysis was performed using standard AOAC methods and mineral contents were determined using atomic absorption spectrometry. The results indicated <em>Peperomia> <em>pellucida> to be rich in crude protein, carbohydrate and total ash contents. The high amount of total ash (31.22% suggests a high-value mineral composition comprising potassium, calcium and iron as the main elements. The present study inferred that <em>Peperomia> <em>pellucida> would serve as a good source of protein and energy as well as micronutrients in the form of a leafy vegetable for human consumption.
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Directory of Open Access Journals (Sweden)
Yuangang Zu
2012-05-01
Full Text Available The aim of this study was to investigate the antioxidant and free-radical scavenging activity of extract and fractions from various parts of <em>Elsholtzia ciliataem>. The inflorescences, leaves, stems and roots of <em>E. ciliataem> were extracted separately and two phenolic component enrichment methods: ethyl acetate-water liquid-liquid extraction and macroporous resin adsorption-desorption, were adopted in this study. The antioxidant activities of water extracts and fractions of <em>E. ciliataem> were examined using different assay model systems <em>in vitroem>. The fraction root E (purified by HPD300 macroporous resin exhibited the highest total phenolics content (497.2 ± 24.9 mg GAE/g, accompanied with the highest antioxidant activity against various antioxidant systems <em>in vitroem> compared to other fractions. On the basis of the results obtained, <em>E. ciliataem> extracts can be used potentially as a ready accessible and valuable bioactive source of natural antioxidants.
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Directory of Open Access Journals (Sweden)
Giovanni Amori
1986-12-01
Full Text Available Abstract In Italy there are two species of <em>Apodemus> (<em>Sylvaemus>: <em>Apodemus sylvaticusem> on the mainland and the main island, and <em>Apodemus flavicollisem> only on the mainland. The trend of some morphometric characters of the skull (incisive foramen length - FI; interorbital breadth = IO; length of palatal bridge = PP; upper alveolar length = $M^1M^3$ was analized and some theoretical models verified for <em>A. sylvaticusem>. If one considers the sympatric population of <em>A. sylvaticusem> and <em>A. flavicollisem> simultaneously the characters PP, IO and $M^1M^3$ appear significantly isometric being directly correlated ($P leq O.O1$, while FI character results allometric with respect to the previous ones, as expected. If one considers the sympatric populations of each of the species separately, the scenario is different. For <em>A. sylvaticusem> only PP and $M^1M^3$ are isometric ($P leq 0.05$. For <em>A. flavicollisem> only $M^1M^3$ and FI appear to be correlated, although not as significantly as for <em>A. sylvaticusem> ($P le 0.05$; one tail. The insular populations of <em>A. sylvaticusem> do not show significant correlations, except for FI and $M^1M^3$ ($P le 0.05$. On the contrary, considering all populations, sympatric and allopatric, of <em>A. sylvaticusem> at the same time are significant correlations ($P le 0.05$ in all combinations of characters, except for those involving the IO. We suggest that the isometric relations in sympatric assemblages are confined within a morphological range available to the genus <em>Apodemus>. In such a space, the two species are split in two different and innerly homogeneous distributions. We found no evidence to confirm the niche variation hypothesis. On the contrary, the variability expressed as SO or CV's appears higher in the sympatric populations than in the allopatric ones, for three of the four characters, confirming previous results
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Directory of Open Access Journals (Sweden)
Min Huang
2012-05-01
Full Text Available An apoptosis correlated molecule—protein Latcripin-1 of <em>Lentinula
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Photoactive dye-enhanced tissue ablation for endoscopic laser prostatectomy.
Ahn, Minwoo; Hau, Nguyen Trung; Van Phuc, Nguyen; Oh, Junghwan; Kang, Hyun Wook
2014-11-01
Laser light has been widely used as a surgical tool to treat benign prostate hyperplasia (BPH) over 20 years. Recently, application of high laser power up to 200 W was often reported to swiftly remove a large amount of prostatic tissue. The purpose of this study was to validate the feasibility of photoactive dye injection to enhance light absorption and eventually to facilitate tissue vaporization with low laser power. Chicken breast tissue was selected as a target tissue due to minimal optical absorption at the visible wavelength. Four biocompatible photoactive dyes, including amaranth (AR), black dye (BD), hemoglobin powder (HP), and endoscopic marker (EM), were selected and tested in vitro with a customized 532 nm laser system with radiant exposure ranging from 0.9 to 3.9 J/cm(2) . Light absorbance and ablation threshold were measured with UV-Vis spectrometer and Probit analysis, respectively, and compared to feature the function of the injected dyes. Ablation performance with dye-injection was evaluated in light of radiant exposure, dye concentration, and number of injection. Higher light absorption by injected dyes led to lower ablation threshold as well as more efficient tissue removal in the order of AR, BD, HP, and EM. Regardless of the injected dyes, ablation efficiency principally increased with radiant exposure, dye concentration, and number of injection. Among the dyes, AR created the highest ablation rate of 44.2 ± 0.2 µm/pulse due to higher absorbance and lower ablation threshold. High aspect ratios up to 7.1 ± 0.4 entailed saturation behavior in the tissue ablation injected with AR and BD, possibly resulting from plume shielding and increased scattering due to coagulation. Preliminary tests on canine prostate with a hydraulic injection system demonstrated that 80 W with dye injection yielded comparable ablation efficiency to 120 W with no injection, indicating 33% reduced laser power with almost equivalent performance. Due to
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3D Laser Imprint Using a Smoother Ray-Traced Power Deposition Method
Schmitt, Andrew J.
2017-10-01
Imprinting of laser nonuniformities in directly-driven icf targets is a challenging problem to accurately simulate with large radiation-hydro codes. One of the most challenging aspects is the proper construction of the complex and rapidly changing laser interference structure driving the imprint using the reduced laser propagation models (usually ray-tracing) found in these codes. We have upgraded the modelling capability in our massively-parallel fastrad3d code by adding a more realistic EM-wave interference structure. This interference model adds an axial laser speckle to the previous transverse-only laser structure, and can be impressed on our improved smoothed 3D raytrace package. This latter package, which connects rays to form bundles and performs power deposition calculations on the bundles, is intended to decrease ray-trace noise (which can mask or add to imprint) while using fewer rays. We apply this improved model to 3D simulations of recent imprint experiments performed on the Omega-EP laser and the Nike laser that examined the reduction of imprinting due to very thin high-Z target coatings. We report on the conditions in which this new model makes a significant impact on the development of laser imprint. Supported by US DoE/NNSA.
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DEFF Research Database (Denmark)
Sonne, Si Brask; Dalgaard, Marlene D; Nielsen, John Erik
2009-01-01
Microarray and RT-PCR based methods are important tools for analysis of gene expression; however, in tissues containing many different cells types, such as the testis, characterization of gene expression in specific cell types can be severely hampered by noise from other cells. The laser microdis......Microarray and RT-PCR based methods are important tools for analysis of gene expression; however, in tissues containing many different cells types, such as the testis, characterization of gene expression in specific cell types can be severely hampered by noise from other cells. The laser...... protocols, and present two staining protocols for frozen sections, one for fast and specific staining of fetal germ cells, testicular carcinoma in situ cells, and other cells with embryonic stem cell-like properties that express the alkaline phosphatase, and one for specific staining of lipid droplet...
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Momentos em freios e em embraiagens
Mimoso, Rui Miguel Pereira
2011-01-01
Dissertação para obtenção do Grau de Mestre em Mestrado Integrado em Engenharia Mecânica Nesta dissertação reúnem-se os modelos de cálculo utilizados na determinação dos momentos em freios e em embraiagens. Neste trabalho consideram-se os casos de freios e embraiagens de atrito seco e atrito viscoso. Nos freios de atrito viscoso são considerados casos em que as características dos fluidos não são induzidas, e outros em que são induzidas modificações a essas mesmas características. São a...
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Directory of Open Access Journals (Sweden)
Vittorio Guberti
1991-07-01
Full Text Available Abstract A parasitological survey on 153 foxes was carried out in the northern Apennines, during the period 1984-1987. The following parasites were identified: <em>Toxocara canisem> (46.4%, <em>Taenia> sp. (17%, <em>Uncinaria stenocephalaem> (11.8%, <em>Mesocestoides lineatusem> (11.1%, <em>Ancylostoma caninumem> (3.9%, <em>Taenia hydatigenaem> (3.3%, <em>Trichuris vulpisem> (3.3%, <em>Dipylidium caninumem> (2.6%, <em>Taenia crassicepsem> (2%. All foxes were negative for <em>Trichinella> sp. A statistical analysis was performed to evaluate differences in the parasitic fauna according to the sex and age classes of the hosts. The role that the fox could have as a reservoir of helminthic zoonoses is discussed. The results are compared with those of similar studies carried out in Italy. Riassunto Nel periodo 1984-1987 è stata condotta un'indagine parassitologica su 153 volpi abbattute nell'Appennino romagnolo. Sono stati reperiti i seguenti parassiti: <em>Toxocara canisem> (46,4%, <em>Taenia> sp. (17%, <em>Uncinaria stenocephalaem> (11,8%, <em>Mesocestoides lineatusem> (11,1%, <em>Ancylostoma caninumem> (3,9%, <em>Taenia hydatigenaem> (3,3%, <em>Trichuris vulpisem> (3,3%, <em>Dipylidium caninumem> (2,6%, <em>Taenia crassicepsem> (2%. Tutte le volpi esaminate sono risultate negative per <em>Trichinella> sp. È stata effettuata l'analisi statistica dei dati per evidenziare eventuali differenze della fauna parassitaria in relazione al sesso e all'età delle volpi. Sulla base dei dati ottenuti viene discussa l'importanza che la Volpe può assumere come serbatoio di zoonosi elmintiche. I risultati acquisiti sono inoltre comparati con quelli ottenuti in analoghe ricerche condotte in Italia.
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<em>In Vivoem> Histamine Optical Nanosensors
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Heather A. Clark
2012-08-01
Full Text Available In this communication we discuss the development of ionophore based nanosensors for the detection and monitoring of histamine levels <em>in vivoem>. This approach is based on the use of an amine-reactive, broad spectrum ionophore which is capable of recognizing and binding to histamine. We pair this ionophore with our already established nanosensor platform, and demonstrate <em>in vitroem> and <em>in vivoem> monitoring of histamine levels. This approach enables capturing rapid kinetics of histamine after injection, which are more difficult to measure with standard approaches such as blood sampling, especially on small research models. The coupling together of <em>in vivoem> nanosensors with ionophores such as nonactin provide a way to generate nanosensors for novel targets without the difficult process of designing and synthesizing novel ionophores.
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Directory of Open Access Journals (Sweden)
Dino Scaravelli
2003-10-01
Full Text Available I due <em>Neomys> italiani sono ancora da chiarire dal punto di vista della loro caratterizzazione morfologica e ecologica. Il lavoro prende in considerazione un campione di entrambe le specie proveniente da habitat forestali dell?Appennino settentrionale per i quali sono stati identificati i principali parametri ambientali. Vengono quindi descritte la variabilità dei tratti morfologici delle due specie in aree localizzate nel Parco Nazionale Foreste Casentinesi, Monte Falterona e Campigna nell?Appennino tosco-romagnolo. Risultano di sicuro effetto discriminatorio la maschera facciale, il rapporto piede posteriore/coda e i caratteri cranici. Sulla base dei criteri identificativi si sono realizzate rilevazioni di misure corporee per le due specie e una comparazione degli habitat utilizzati. <em>N. fodiensem> appare unica specie nelle faggete-abetine e dominante nei castagneti, mentre nell?Ontaneta e nelle zone aperte e termofile si registra la sola presenza di <em>N. anomalusem>. Mancano entrambi nei prati cespugliati, nella pecceta e nella cerreta. I gradienti presenti sono quindi illustrati. Non appare una differenza altitudinale nel campione esaminato, posto in stazioni tra i 400 e i 1300 m, ma per entrambe vi sono maggiori riscontri nella fascia tra 700 e 850 m. Nell?analisi multivariata rispetto alle altre specie e alle variabili ambientali si riscontra sempre una discreta correlazione con la presenza di acqua di una certa ampiezza, che comunque è significativa solo per <em>N. fodiensem>, mentre risulta di interesse la positiva correlazione di <em>N. anomalusem> con <em>Apodemus sylvaticusem>.
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Directory of Open Access Journals (Sweden)
Egoitz Salsamendi
2006-03-01
Full Text Available Abstract <em>Rhinolophus euryaleem> and <em>R. mehelyiem> are morphologically very similar species and their distributions overlap extensively in the Mediterranean basin. We modelled their foraging behaviour using echolocation calls and wing morphology and, assuming niche segregation occurs between the two species, we explored how it is shaped by these factors. Resting frequency of echolocation calls was recorded and weight, forearm length, wing loading, aspect ratio and wing tip shape index were measured. <em>R. mehelyiem> showed a significantly higher resting frequency than <em>R. euryaleem>, but differences are deemed insufficient for dietary niche segregation. Weight and forearm length were significantly larger in <em>R. mehelyiem>. The higher values of aspect ratio and wing loading and a lower value of wing tip shape index in <em>R. melehyiem> restrict its flight manoeuvrability and agility. Therefore, the flight ability of <em>R. mehelyiem> may decrease as habitat complexity increases. Thus, the principal mechanism for resource partitioning seems to be based on differing habitat use arising from differences in wing morphology. Riassunto Ecolocalizzazione e morfologia nei rinolofi di Mehely (<em>Rhinolophus mehelyiem> e euriale (<em>R. euryaleem>: implicazioni nella segregazione delle risorse trofiche. <em>Rhinolophus euryaleem> e <em>R. mehelyiem> sono specie morfologicamente molto simili, la cui distribuzione risulta largamente coincidente in area mediterranea. Il comportamento di foraggiamento delle due specie è stato analizzato in funzione delle caratteristiche dei segnali di ecolocalizzazione e della morfologia alare, ed è stata valutata l’incidenza di questi fattori nell’ipotesi di una segregazione delle nicchie. È stata rilevata la frequenza a riposo dei segnali ultrasonori, così come il peso, la lunghezza dell’avambraccio, il carico alare, e due
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Directory of Open Access Journals (Sweden)
Jeanne F. Millogo
2012-06-01
Full Text Available This paper describes a preliminary assessment of the nutraceutical value of <em>Amaranthus cruentus (A. cruentusem> and <em>Amaranthus hybridus (A. hybridusem>, two food plant species found in Burkina Faso. Hydroacetonic (HAE, methanolic (ME, and aqueous extracts (AE from the aerial parts were screened for <em>in vitroem> antioxidant and xanthine oxidase inhibitory activities. Phytochemical analyses revealed the presence of polyphenols, tannins, flavonoids, steroids, terpenoids, saponins and betalains. Hydroacetonic extracts have shown the most diversity for secondary metabolites. The TLC analyses of flavonoids from HAE extracts showed the presence of rutin and other unidentified compounds. The phenolic compound contents of the HAE, ME and AE extracts were determined using the Folin–Ciocalteu method and ranged from 7.55 to 10.18 mg Gallic acid equivalent GAE/100 mg. Tannins, flavonoids, and flavonols ranged from 2.83 to 10.17 mg tannic acid equivalent (TAE/100 mg, 0.37 to 7.06 mg quercetin equivalent (QE /100 mg, and 0.09 to 1.31 mg QE/100 mg, respectively. The betacyanin contents were 40.42 and 6.35 mg Amaranthin Equivalent/100 g aerial parts (dry weight in <em>A. cruentusem> and <em>A. hybridusem>, respectively. Free-radical scavenging activity expressed as IC50 (DPPH method and iron reducing power (FRAP method ranged from 56 to 423 µg/mL and from 2.26 to 2.56 mmol AAE/g, respectively. Xanthine oxidase inhibitory activities of extracts of <em>A. cruentus em>and <em>A. hybridusem> were 3.18% and 38.22%, respectively.<em> em>The
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Dermatoses em renais cronicos em terapia dialitica
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Luis Alberto Batista Peres
2014-03-01
Full Text Available Objetivo: As desordens cutâneas e das mucosas são comuns em pacientes em hemodiálise a longo prazo. A diálise prolonga a expectativa de vida, dando tempo para a manifestação destas anormalidades. Os objetivos deste estudo foram avaliar a prevalência de problemas dermatológicos em pacientes com doença renal crônica (DRC em hemodiálise. Métodos: Cento e quarenta e cinco pacientes com doença renal crônica em hemodiálise foram estudados. Todos os pacientes foram completamente analisados para as alterações cutâneas, de cabelos, mucosas e unhas por um único examinador e foram coletados dados de exames laboratoriais. Os dados foram armazenados em um banco de dados do Microsolft Excel e analisados por estatística descritiva. As variáveis contínuas foram comparadas pelo teste t de Student e as variáveis categóricas utilizando o teste do qui-quadrado ou o teste Exato de Fischer, conforme adequado. Resultados: O estudo incluiu 145 pacientes, com idade média de 53,6 ± 14,7 anos, predominantemente do sexo masculino (64,1% e caucasianos (90,0%. O tempo médio de diálise foi de 43,3 ± 42,3 meses. As principais doenças subjacentes foram: hipertensão arterial em 33,8%, diabetes mellitus em 29,6% e glomerulonefrite crônica em 13,1%. As principais manifestações dermatológicas observadas foram: xerose em 109 (75,2%, equimose em 87 (60,0%, prurido em 78 (53,8% e lentigo em 33 (22,8% pacientes. Conclusão: O nosso estudo mostrou a presença de mais do que uma dermatose por paciente. As alterações cutâneas são frequentes em pacientes em diálise. Mais estudos são necessários para melhor caracterização e manejo destas dermatoses.
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Yasuhiro Ozeki
2012-04-01
Full Text Available A divalent cation-independent lectin—HOL-18, with cytotoxic activity against leukemia cells, was purified from a demosponge, <em>Halichondria okadaiem>. HOL-18 is a 72 kDa tetrameric lectin that consists of four non-covalently bonded 18 kDa subunits. Hemagglutination activity of the lectin was strongly inhibited by chitotriose (GlcNAcβ1-4GlcNAcβ1-4GlcNAc, fetuin and mucins from porcine stomach and bovine submaxillary gland. Lectin activity was stable at pH 4–12 and temperatures lower than 60 °C. Frontal affinity chromatography with 16 types of pyridylaminated oligosaccharides indicated that the lectin had an affinity for <em>N>-linked complex-type and sphingolipid-type oligosaccharides with <em>N>-acetylated hexosamines and neuramic acid at the non-reducing termini. The lectin killed Jurkat leukemia T cells and K562 erythroleukemia cells in a dose- and carbohydrate-dependent manner.
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Carlos E. Bueso-Ramos
2012-08-01
Full Text Available Environmental exposure to benzene occurs through cigarette smoke, unleaded gasoline and certain types of plastic. Benzene is converted to hematotoxic metabolites by the hepatic phase-I enzyme CYP2E1, and these metabolites are detoxified by the phase-II enzyme NQO1. The genes encoding these enzymes are highly polymorphic and studies of these polymorphisms have shown different pathogenic and prognostic features in various hematological malignancies. The potential role of different cytochrome p450 metabolizing enzymes in the pathogenesis of acute myeloid leukemia (AML in an area of active interest. In this study, we demonstrate aberrant CYP2E1 mRNA over-expression by quantitative real-time polymerase chain reaction in 11 cases of <em>de novoem> AML with inv(16; CBFβ-MYH11. CYP2E1 mRNA levels correlated with <em>CBFβ
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Interaction of Intense Lasers with Plasmas
Shvets, Gennady
1995-01-01
This thesis addresses two important topics in nonlinear laser plasma physics: the interaction of intense lasers with a non thermal homogeneous plasma, the excitation of laser wakefields in hollow plasma channels, and the stability of channel guided propagation of laser pulses. In the first half of this thesis a new theoretical approach to the nonlinear interaction of intense laser pulses with underdense plasmas is developed. Unlike previous treatments, this theory is three-dimensional, relativistically covariant, and does not assume that astudied. An experimental check of this calculation is suggested, based on the predicted non-linear polarization rotation (the second harmonic is emitted polarized perpendicularly to polarization of the incident signal). The concept of renormalization is applied to the plasma and electromagnetic radiation (photons and plasmons). To the lowest order, this corresponds to relativistically correcting the electron mass for its oscillation in an intense EM field and to replacing the vacuum dispersion relation by the usual relativistic plasma dispersion relation. This renormalization procedure is then carried to higher order in epsilon=omega_sp{p} {2}a^2/[(1+a^2/2)^ {3/2}omega^2]. This yields the nonlinear modification of the index of refraction of a strong electromagnetic wave and the dispersion of a weak probe in the presence of the wave. In the second part of this thesis the stability of short laser pulses propagating through parabolic channels and the wake excitation of hollow plasma channels are studied. The stability of a channel guided short laser pulse propagation is analyzed for the first time. Perturbations to the laser pulse are shown to modify the ponderomotive pressure, which distorts the dielectric properties of the plasma channel. The channel perturbation then further distorts the laser pulse. A set of coupled mode equations is derived, and a matrix dispersion relation is obtained analytically. The ponderomotive excitation
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Lívia Souza Pugliese
2003-12-01
Full Text Available The study of low-level laser therapy upon extracellular matrix elements is important to understand the wound healing process under this agent. However, little is known about the interference of laser light in relation to collagen and elastic fibers. Cutaneous wounds were performed on the back of 72 Wistar rats and a Ga-Al-As low-level laser was punctually applied with different energy densities. The animals were killed after 24, 48, 72 hours and 5, 7 and 14 days. Tissues were stained with hematoxilin-eosin, sirius red fast green and orcein and then analyzed. It was observed that the treated group exhibited larger reduction of edema and inflammatory infiltrate. The treated animals presented a larger expression of collagen and elastic fibers, although without statistical significance (p > 0.05. Treatment with a dosage of 4 J/cm² exhibited more expressive results than that with 8 J/cm². In this study, the authors concluded that low-level laser therapy contributed to a larger expression of collagen and elastic fibers during the early phases of the wound healing process.O estudo da terapia a laser de baixa densidade de energia sobre os diversos constituintes da matriz extracelular é crucial para o entendimento do processo cicatricial sob esse agente. Todavia, pouco se sabe sobre a interferência do laser em relação às fibras colágenas e elásticas. Realizaram-se ferimentos cutâneos padronizados no dorso de setenta e dois ratos Wistar e, em seguida, aplicação pontual do raio laser de baixa potência do tipo Arseneto de Gálio-Alumínio (Ga-Al-As com diferentes densidades de energia. Os animais foram sacrificados com 24, 48 e 72 horas e aos 5, 7 e 14 dias. Procedeu-se à análise das secções teciduais coradas por hematoxilina-eosina, sírius vermelho e orceína. Observou-se, que nos grupos submetidos à terapia a laser, houve maior redução do edema e infiltrado inflamatório. Os animais tratados apresentaram uma maior expressão de fibras
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Directory of Open Access Journals (Sweden)
E. Antonelli
2009-03-01
Full Text Available São apresentados os resultados de sinterização de filmes espessos de BaTi0,85Zr0,15O3 (BTZ15, depositados pela técnica de eletroforese, utilizando como fonte de calor um laser de CO2. A montagem experimental foi otimizada de modo a permitir a sinterização de filmes com dimensões de até 70 mm de comprimento por 10mm de largura e espessuras variáveis. Os processos térmicos envolvidos durante a varredura contínua a laser atuaram de modo similar à sinterização em duas etapas. Os tempos de patamares em cada etapa foram dependentes da velocidade e do número de varreduras. A temperatura máxima que se pode atingir no filme espesso, durante cada varredura e para uma potência nominal do laser fixa, foi correlacionada com a densidade relativa. Após sinterizados, os filmes apresentaram homogeneidade microestrutural e uma porosidade aparente de ~7%.The results for sintering of BaTi0.85Zr0.15O3 (BTZ15 thick films, deposited by electrophoresis, using as heat source a CO2 laser are presented. The characteristics of the experimental apparatus were optimized in such a way as to allow the sintering of thick films whose dimensions were up to 70 mm in length, 10 mm in width and variable thicknesses. The related thermal process during the continuous laser scanning acted in a similar way as a two-step sintering. The step times in each stage were dependent on the speed and scan number. The maximum temperature that can be achieved in the thick film, during each scanning, and for a fixed rated laser power, was correlated with the relative density. After sintering the films presented a microstructural homogeneity and an apparent porosity of ~7%.
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Alexandre Novicki
2011-01-01
Nesse trabalho, apresentamos o desenvolvimento de uma proposta para o ensino da disciplina de Biofísica para o Curso de Fisioterapia, tendo como instrumento motivador os aparelhos operados em Eletrotermofototerapia, como o Laser e o Ultrassom, por exemplo, e como base, os princípios físicos que permitem o uso e operação destes aparelhos. A proposta de se rever o processo ensino/aprendizagem da disciplina de Biofísica foi motivada pela constatação de que nossos alunos, em geral, não demonstram...
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Melanosomes are a primary target of Q-switched ruby laser irradiation in guinea pig skin
Energy Technology Data Exchange (ETDEWEB)
Polla, L.L.; Margolis, R.J.; Dover, J.S.; Whitaker, D.; Murphy, G.F.; Jacques, S.L.; Anderson, R.R.
1987-09-01
The specific targeting of melanosomes may allow for laser therapy of pigmented cutaneous lesions. The mechanism of selective destruction of pigmented cells by various lasers, however, has not been fully clarified. Black, brown, and albino guinea pigs were exposed to optical pulses at various radiant exposure doses from a Q-switched, 40 nsec, 694 nm ruby laser. Biopsies were analyzed by light and electron microscopy (EM). Albino animals failed to develop clinical or microscopic evidence of cutaneous injury after irradiation. In both black and brown animals, the clinical threshold for gross change was 0.4 J/cm2, which produced an ash-white spot. By light microscopy, alterations appeared at 0.3 J/cm2 and included separation at the dermoepidermal junction, and the formation of vacuolated epidermal cells with a peripheral cytoplasmic condensation of pigment. By EM, enlarged melanosomes with a central lucent zone were observed within affected epidermal cells at 0.3 J/cm2. At 0.8 and 1.2 J/cm2, individual melanosomes were more intensely damaged and disruption of melanosomes deep in the hair papillae was observed. Dermal-epidermal blisters were formed precisely at the lamina lucida, leaving basal cell membranes and hemidesmosomes intact. Possible mechanisms for melanosomal injury are discussed. These observations show that the effects of the Q-switched ruby laser are melanin-specific and melanin-dependent, and may be useful in the selective destruction of pigmented as well as superficial cutaneous lesions.
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João Carlos de Miranda Gonçalves
2004-02-01
Full Text Available PURPOSE: Transscleral diode retinal photocoagulation (diopexy is becoming an accepted technique in the treatment of selected retinal diseases. The objective of this study is to evaluate diopexy technique in the production of adhesive chorioretinal lesions during the surgical treatment of the rhegmatogenous retinal detachment. METHODS: 25 patients with rhegmatogenous retinal detachment were enrolled in a prospective clinical-surgical study to evaluate the technique of transscleral diode laser photocoagulation to obtain adhesive chorioretinal lesions during retinal reattachment surgery. The surgery consisted of the placement of an exoplant silicon to produce a buckle effect combined with a drainage of subretinal fluid in most cases. RESULTS: By a mean follow-up of 10 months, 21 of 25 eyes had their retinas reattached after only one surgery with diopexy used in all cases. CONCLUSION: Transscleral diode laser photocoagulation was a technically easy, controlled, effective, reproducible and safe means of obtaining chorioretinal adhesion in retinal reattachment surgery.OBJETIVO: Fotocoagulação transescleral com laser de diodo (diopexia está se tornando técnica utilizada no tratamento de algumas doenças retinianas. O objetivo deste estudo é avaliar a técnica de diopexia na produção de lesões coriorretinianas aderentes durante o tratamento cirúrgico do descolamento de retina regmatogênico. MÉTODOS: Vinte e cinco pacientes com descolamento de retina regmatogênico participaram deste estudo clínico-cirúrgico prospectivo para avaliar a técnica de fotocoagulação com laser de diodo transescleral para obter lesões coriorretinianas aderentes durante a cirurgia de descolamento de retina. A cirurgia consistiu de colocação de explante de silicone para produzir efeito de introflexão escleral combinado com drenagem do líquido subretiniano na maioria dos casos. RESULTADOS: Após um período médio de seguimento de 10 meses, em 21 dos 25 olhos
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The effect of soft-laser (diodes radiation on wound healing in cats
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Julia Maria Matera
1994-03-01
Full Text Available Verificou-se o valor do emprego do laser diodo Ga-As-SHLD para auxiliar o processo de cicatrizarão cutânea em felinos. Utilizaram-se 21 animais que foram submetidos à ovariohisterectomia, 9 pertencendo ao grupo controle e 12 submetidos à laserterapia. Os exames anatomopatológicos foram realizados nos dias 2, 4 e 8 de pós-operatório, juntamente com avaliação macroscópica. Concluiu-se que a aplicação do laser diodo Ga-As-SHLD auxiliou o processo cicatricial da ferida cirúrgica por aumento de resistência à tensão.
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Fernando Coutinho
2007-08-01
Full Text Available OBJETIVO: Avaliar, por meio de estudo bacteriológico in vitro, o efeito de dois tipos de laser de baixa energia (LBE sobre diferentes populações bacterianas habitualmente presentes em feridas pós-traumáticas. MÉTODOS: Foram colhidos swabs diretamente do sítio de infecção de pacientes internados com osteomielite pós-traumática crônica. As bactérias isoladas foram Acinetobacter baumanii complex, Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonela sp, Serratia sp e Staphylococcus aureus. O material coletado foi semeado em meio ágar-sangue, através de alça estéril, utilizando-se 30 placas de Petri para cada germe. Foram utilizados dois aparelhos de LBE: Ibramed Laser Pulse #01189, com 15W/904nm por 200 segundos, e Phisiolux dual Bioset #9909001, com 20W/904nm por 230 segundos. Nos grupos I (n = 10 e II (n = 10, as bactérias sofreram irradiação pelo laser. O grupo III (n = 10 serviu de controle, não sendo irradiado. As bactérias dos grupos I e II foram irradiadas em câmara de fluxo laminar, previamente esterilizada por raio ultravioleta. O laser foi administrado de forma direta, central e perpendicularmente à superfície de cultivo das bactérias, com distância-padrão de 1cm, através de orifício confeccionado na tampa das placas. O crescimento bacteriano foi analisado após 12 e 24 horas da irradiação. Os resultados foram processados estatisticamente, utilizando-se o teste não-paramétrico de Kruskall-Wallis, com nível de significância p OBJECTIVE: To perform an in vitro bacteriologic study to evaluate the effect of two types of low level laser (LLL on different bacterial populations usually present in post-traumatic wounds. METHODS: Swabs were prepared directly at the infection site of patients hospitalized with chronic post-traumatic osteomyelitis. Isolated bacteria were Acinetobacter baumanii complex, Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae
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Thermal Studies of Zn(II, Cd(II and Hg(II Complexes of Some <em>N-Alkyl-N>-Phenyl-Dithiocarbamates
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Peter A. Ajibade
2012-07-01
Full Text Available The thermal decomposition of Zn(II, Cd(II and Hg(II complexes of <em>N-ethyl-N>-phenyl and <em>N-butyl-N>-phenyl dithiocarbamates have been studied using thermogravimetric analysis (TGA and differential scanning calorimetry (DSC. The products of the decomposition, at two different temperatures, were further characterized by scanning electron microscopy (SEM and energy-dispersive X-ray spectroscopy (EDX. The results show that while the zinc and cadmium complexes undergo decomposition to form metal sulphides, and further undergo oxidation forming metal oxides as final products, the mercury complexes gave unstable volatiles as the final product.
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Impact of pulse duration on Ho:YAG laser lithotripsy: fragmentation and dusting performance.
Bader, Markus J; Pongratz, Thomas; Khoder, Wael; Stief, Christian G; Herrmann, Thomas; Nagele, Udo; Sroka, Ronald
2015-04-01
In vitro investigations of Ho:YAG laser-induced stone fragmentation were performed to identify potential impacts of different pulse durations on stone fragmentation characteristics. A Ho:YAG laser system (Swiss LaserClast, EMS S.A., Nyon, Switzerland) with selectable long or short pulse mode was tested with regard to its fragmentation and laser hardware compatibility properties. The pulse duration is depending on the specific laser parameters. Fragmentation tests (hand-held, hands-free, single-pulse-induced crater) on artificial BEGO stones were performed under reproducible experimental conditions (fibre sizes: 365 and 200 µm; laser settings: 10 W through combinations of 0.5, 1, 2 J/pulse and 20, 10, 5 Hz, respectively). Differences in fragmentation rates between the two pulse duration regimes were detected with statistical significance for defined settings. Hand-held and motivated Ho:YAG laser-assisted fragmentation of BEGO stones showed no significant difference between short pulse mode and long pulse mode, neither in fragmentation rates nor in number of fragments and fragment sizes. Similarly, the results of the hands-free fragmentation tests (with and without anti-repulsion device) showed no statistical differences between long pulse and short pulse modes. The study showed that fragmentation rates for long and short pulse durations at identical power settings remain at a comparable level. Longer holmium laser pulse duration reduces stone pushback. Therefore, longer laser pulses may result in better clinical outcome of laser lithotripsy and more convenient handling during clinical use without compromising fragmentation effectiveness.
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Roberto Ferreira Meirelles Jr.
2003-01-01
Full Text Available PURPOSE: The pancreatic capillary blood flow (PCBF was studied to determine its alterations during caerulein-induced pancreatitis in rats. METHODS: Twenty rats were divided in groups: control and caerulein. A laser-Doppler flowmeter to measure PCBF continuously was used. Blood pressure (BP and heart rate (HR were monitored. Serum biochemistry analyses were determined. Histopathological study was performed. RESULTS: The PCBF measured a mean of 109.08 ± 14.54% and 68.24 ± 10.47% in control group and caerulein group, respectively. Caerulein group had a mean decrease of 31.75 ± 16.79%. The serum amylase was 1323.70 ± 239.10U.I-1 and 2184.60 ± 700.46U.I-1 in control and caerulein groups, respectively. There was a significant difference in the PCBF (pOBJETIVO: O fluxo capilar pancreático (FCP foi estudado para determinar suas alterações durante a pancreatite aguda induzida por ceruleína, em ratos. MÉTODOS: Vinte ratos foram divididos em grupo controle e grupo ceruleína. Um laser-Doppler fluxímetro foi empregado para determinar, continuamente, o FCP durante 120 minutos. A pressão arterial média (PAM e a freqüência cardíaca (FC foram determinadas, durante o experimento. Análise bioquímica sérica e estudo histopatológico, por microscopia ótica, do tecido pancreático foram realizados, ao final do experimento. RESULTADOS: O FCP foi em média 109,08 ± 2,17% e 68,24 ± 16,79% nos grupos controle e ceruleína , respectivamente. No grupo ceruleína, houve uma diminuição média de 31,75 ± 16,79%. Os níveis de amilase sérica foram de 1323,70 ± 239,10U.I-1 e 2184,60 ± 700,46U.I-1 nos grupos controle e ceruleína, respectivamente. Houve diferença significante (p<0,05 no FCP e na amilasemia, quando comparado o grupo controle com o grupo ceruleína. Embora micro e macrovacuolização estivessem presentes no grupo ceruleína, não houve diferença histológica entre os grupos. CONCLUSÃO: A diminuição do FCP parece um evento precoce
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Conservazione e gestione della Lepre italica (<em>Lepus corsicanusem>
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Francesco Riga
2003-10-01
Full Text Available Il recente riconoscimento dello <em>status> specifico della Lepre italica (<em>Lepus corsicanusem> e l?accertamento dell?areale distributivo rappresentano le azioni più importanti per la conservazione di un <em>taxon endemicoem> che si era creduto estinto. Nella penisola la specie presenta un areale discontinuo, il cui limite settentrionale è dato dal comune di Manciano (GR, sul versante tirrenico e da una linea che dalla provincia de L'Aquila arriva al Gargano. In Sicilia la distribuzione è relativamente continua anche in aree non protette. Dati genetici hanno permesso di confermare la presenza in Corsica. Al contrario, nell?Isola d'Elba, a seguito di estese ricerche, sono stati identificati solo esemplari di <em>L. europaeusem>. Nell?Italia peninsulare <em>L. corsicanusem> è spesso presente in simpatria con popolazioni di <em>L. europaeusem>, mentre in Sicilia la lepre europea non ha originato popolazioni stabili, nonostante l?immissione di molte migliaia di individui. La distribuzione ecologica di <em>L. corsicanusem> ed analisi ambientali specifiche, suggeriscono l?adattamento prevalente agli ambienti a clima mediterraneo, benché essa sia presente anche a quote elevate (> 1.500 m s.l.m.. Dati preliminari di abbondanza relativa hanno evidenziato una situazione diversificata tra la penisola e la Sicilia e tra aree a diverso regime di gestione; un confronto tra le aree protette ha evidenziato rispettivamente valori di 5,54 e 11,73 ind./km². La riduzione quali-quantitativa e la frammentazione dell?<em>habitat> delle lepri è un fenomeno potenzialmente pericoloso per la sopravvivenza delle popolazioni, determinando fenomeni di estinzione locale dovuti alle basse densità di popolazione, inducendo fenomeni di erosione della variabilità genetica e di riduzione della <em>fitness> degli individui. L?introduzione di <em>L. europaeusem> può costituire un importante fattore limitante sia per la possibile competizione
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Methyl 2-Benzamido-2-(1<em>H>-benzimidazol-1-ylmethoxyacetate
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Alami Anouar
2012-09-01
Full Text Available The heterocyclic carboxylic α-aminoester methyl 2-benzamido-2-(1<em>H>-benzimidazol-1-ylmethoxyacetate is obtained by <em>O>-alkylation of methyl α-azido glycinate <em>N>-benzoylated with 1<em>H>-benzimidazol-1-ylmethanol.
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Wei Lu
2012-06-01
Full Text Available Single nucleotide polymorphisms (SNPs are currently the marker of choice in a variety of genetic studies. Using the high resolution melting (HRM genotyping approach, 101 gene-based SNP markers were developed for <em>Apostichopus japonicusem>, a sea cucumber species with economic significance for the aquaculture industry in East Asian countries. HRM analysis revealed that all the loci showed polymorphisms when evaluated using 40 <em>A. japonicusem> individuals collected from a natural population. The minor allele frequency ranged from 0.035 to 0.489. The observed and expected heterozygosities ranged from 0.050 to 0.833 and 0.073 to 0.907, respectively. Thirteen loci were found to depart significantly from Hardy–Weinberg equilibrium (HWE after Bonferroni corrections. Significant linkage disequilibrium (LD was detected in one pair of markers. These SNP markers are expected to be useful for future quantitative trait loci (QTL analysis, and to facilitate marker-assisted selection (MAS in <em>A. japonicusem>.
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Activity-Guided Isolation of Antioxidant Compounds from <em>Rhizophora apiculataem>
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Hongbin Xiao
2012-09-01
Full Text Available <em>Rhizophora apiculataem> (<em>R. apiculataem> contains an abundance of biologically active compounds due its special salt-tolerant living surroundings. In this study, the total phenolic content and antioxidant activities of various extract and fractions of stem of <em>R. apiculataem> were investigated. Results indicated that butanol fraction possesses the highest total phenolic content (181.84 mg/g GAE/g dry extract with strongest antioxidant abilities. Following <em>in vitroem> antioxidant activity-guided phytochemical separation procedures, lyoniresinol-3α-<em>O>-β-arabinopyranoside (1, lyoniresinol-3α-<em>O>-β-rhamnoside (2, and afzelechin-3-<em>O>-L-rhamno-pyranoside (3 were separated from the butanol fraction. These compounds showed more noticeable antioxidant activity than a BHT standard in the DPPH, ABTS and hydroxyl radical scavenging assays. HPLC analysis results showed that among different plant parts, the highest content of 1–3 was located in the bark (0.068%, 0.066% and 0.011%, respectively. The results imply that the <em>R. apiculataem> might be a potential source of natural antioxidants and 1–3 are antioxidant ingredients in <em>R. apiculataem>.
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Isauremi Vieira de Assunção Pinheiro
2004-09-01
Full Text Available This systematic review was conducted to assess the accuracy of laser fluorescence (DIAGNOdentTM for diagnosis of occlusal caries in permanent teeth, using any sort of gold standard. The MEDLINE, LILACS, BBO and Cochrane library databases accessed by BIREME were searched for English, Spanish and Portuguese-language papers published between 1982 and 2003. Four works in English were selected. DIAGNOdentTM was found to be an accurate method for diagnosis of occlusal caries, mainly if employed simultaneously with visual inspection.Esta revisão sistemática foi realizada para avaliar a precisão da fluorescência a laser (DIAGNOdentTM para o diagnóstico da cárie oclusal em dentes permanentes, utilizando qualquer tipo de gold standard. As bases de dados MEDLINE, LILACS, BBO e Cochrane Library, acessadas via BIREME, foram utilizadas para a busca de artigos em idioma inglês, espanhol e português, publicados de 1982 a 2003. Foram selecionados quatro trabalhos em inglês. Foi observado que o DIAGNOdentTM é um método preciso para o diagnóstico da cárie oclusal, principalmente se associado à inspeção visual.
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Flávia Fonseca Moreira
2011-03-01
Full Text Available A laserterapia é um procedimento utilizado em larga escala nas lesões musculoesqueléticas, devido as suas diversas propriedades, antiinflamatórias, cicatrizantes entre outras. Além disso, há tipos distintos de aparelhos de laser. Mesmo com os diversos modelos experimentais existentes na literatura, não há um consenso sobre a faixa de utilização, bem como o tipo de laser que promove melhor reparo no tecido muscular. Este estudo visa analisar os efeitos da laserterapia de baixa intensidade na expressão de colágeno após lesão muscular. Camundongos Swiss albinos (n=18 foram submetidos à lesão muscular cirúrgica e divididos em dois grupos, controle (C e teste (T. Os animais foram submetidos a uma irradiação diária de 5 J/cm² pelos lasers AsGaAl 830 nm e AsGa 904 nm e, em diferentes tempos de sacrifício (7 e 14 dias. Os resultados não demonstraram diferença estatística significativa na expressão de colágeno em ambos os grupos analisados. Contudo, os dados apontam que a dose de 5 J/cm² do laser AsGa 904 nm promoveu maior deposição de fibras colágenas após 14 dias de tratamento, sugerindo que a terapia seja efetiva na síntese de colágeno. Outros estudos experimentais, em humanos, devem ser propostos para maiores inferências sobre os resultados do laser no tratamento da lesão muscular.The laser therapy is a procedure utilized at long scale in the musculoskeletal injuries, due its anti-inflammatory and reparatory proprieties and others. Besides, there are differents types of laser equipments. Despites with the many experimental models at literature, there is no consensus about the range of application as well as the type of laser that promove of the best repair in muscular tissue. The aim of this study is to analyze the effects of the low level laser therapy in the expression of collagen after muscular injury. Mice Swiss albinos (n=18 were subjected to the muscular surgical injury and separated in two groups, control (C
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Synthesis and Spectroscopic Analysis of Novel 1<em>H-Benzo[d>]imidazoles Phenyl Sulfonylpiperazines
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Amjad M. Qandil
2012-05-01
Full Text Available A group of benzimidazole analogs of sildenafil, 3-benzimidazolyl-4-methoxy-phenylsulfonylpiperazines 2–4 and 3-benzimidazolyl-4-methoxy-<em>N,N>-dimethyl- benzenesulfonamide (5, were efficiently synthesized. Compounds 2–5 were characterized by NMR and MS and contrary to the reported mass spectra of sildenafil, the spectra of the piperazine-containing compounds 2–4 showed a novel fragmentation pattern leading to an <em>m/z> = 316. A mechanism for the formation of this fragment was proposed.
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Gianna Dondini
2004-06-01
Full Text Available Abstract Captivity observation on body weight cycle and digestive efficiency in <em>Pipistrellus kuhliiem> and <em>Hypsugo saviiem> (Chiroptera: Vespertilionidae Many bat species of cold-temperate climate are subject to seasonal variation of temperature and food availability. Fat reserve during summer-autumn is therefore a physiological adaptation to spend the winter months by hibernating or to sustain migration. During a research on bats in urban areas, two juveniles of Kuhl's bat (<em>Pipistrellus kuhliiem>, 2 females and two juveniles of Savi's bat (<em>Hypsugo saviiem>, 1 male and 1 female were collected in 1997 in the urban area of Florence (central Italy. Bats were kept in a cage of 50x40x30 cm with a temperature between 17° and 22° C. Every day they were weighted with an electronic balance before eating mealworms (<em>Tenebrio molitorem>. Digestive efficiency, calculated on dry material, was about 90% for both species. In about six months <em>P. kuhliiem> and <em>H. saviiem> increased on the average of 450% and 280% in weight respectively. Deposition of fat reserve seemed to be faster in <em>P. kuhliiem> than in <em>H. saviiem>. Both species showed a circannual cycle in the variation of weight. Riassunto Molte specie di pipistrelli dei climi temperato-freddi sono soggette a marcate variazioni stagionali di temperatura e disponibilità di cibo. L'accumulo di grasso in tarda estate-autunno è quindi un adattamento fisiologico per trascorrere in ibernazione i mesi invernali o per intraprendere la migrazione. Nell'ambito di una ricerca pluriennale sui pipistrelli in ambienti urbani, 4 esemplari giovani, di cui 2 di Pipistrello albolimbato (<em>Pipistrellus kuhliiem>, 2 femmine e due di Pipistrello di Savi (<em>Hypsugo saviiem>, 1 maschio e 1 femmina, sono stati raccolti nella pianura di Firenze durante l'estate del 1997 e mantenuti in un contenitore di 50x40x30 cm ad
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Study of innervation and vascularization of the thoracic limb of Columba livia
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Raphaela da Cunha Franceschi
2009-12-01
Full Text Available No estudo referente aos territórios vásculo-nervosos em membro torácico de Pombos (Columba livia foram utilizados 10 animais. Após a retirada de penas e pele, procedeu-se à identificação dos nervos no membro torácico direito, iniciando-se pela aplicação de compressas de ácido acético glacial 3% e dissecação de cada ramo do plexo braquial e seus músculos de inervação. Para a identificação dos territórios vasculares realizou-se a abertura da cavidade toracoabdominal, canulação do coração seguida de injeção de látex sintético via ventrículo esquerdo, dissecação dos vasos, medição e confecção de esquemas dos resultados. O plexo braquial é composto pelos nervos axilar, radial, peitoral e medianoulnar, em que os dois primeiros são responsáveis pela inervação da musculatura extensora, enquanto os dois últimos responsabilizam-se pela motricidade da musculatura flexora. Ainda pode ser observado um plexo acessório. O tronco braquiocefálico surge da Aorta ascendente, sendo encontrado um tronco direito e um esquerdo, emitindo as artérias carótida comum e subclávia como troncos principais. Destes surgem vasos que irrigam a cabeça, a região cervical e os membros torácicos. Em todas as aves observou-se uma constância na irrigação e inervação da musculatura, articulações e ossos do membro torácico, onde se pode presumir que existe uma constante na delimitação dos territórios vásculo-nervosos.
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Thin-sheet zinc-coated and carbon steels laser welding
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Peças, P.
1998-04-01
Full Text Available This paper describes the results of a research on CO2 laser welding of thin-sheet carbon steels (zinccoated and uncoated, at several thicknesses combinations. Laser welding has an high potential to be applied on sub-assemblies welding before forming to the automotive industry-tailored blanks. The welding process is studied through the analysis of parameters optimization, metallurgical quality and induced distortions by the welding process. The clamping system and the gas protection system developed are fully described. These systems allow the minimization of common thin-sheet laser welding defects like misalignement, and zinc-coated laser welding defects like porous and zinc volatilization. The laser welding quality is accessed by DIN 8563 standard, and by tensile, microhardness and corrosion tests.
Este artigo descreve os resultados da investigação da soldadura laser de CO2 de chapa fina de acó carbono (simples e galvanizado, em diferentes combinações de espessura. A soldadura laser é um processo de elevado potencial no fabrico de tailored-blanks (sub-conjuntos para posterior enformação, constituidos por varias partes de diferentes materiais e espessuras para a indústria automóvel. São analisados os aspectos de optimização paramétrica, de qualidade metalúrgica da junta soldada e das deformações resultantes da soldadura. São descritos os mecanismos desenvolvidos de fixação das chapas e protecção gasosa, por forma a minimizar os defeitos típicos na soldadura laser de chapa fina como o desalinhamento e da soldadura laser de chapa galvanizada como os poros e a volatilização do zinco. Por fim apresentam-se resultados da avaliação da qualidade da soldadura do ponto de vista qualitativo através da norma DIN 8563, e do pontos de vista quantitativo através de ensaios de tracção, dureza e corrosão. -
Energy Technology Data Exchange (ETDEWEB)
Amaro, Renato; Lomba, Rosana Fatima Teixieira [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil); Perez, Maria Angelica Acosta; Valente, Luiz Carlos Guedes; Braga, Arthur Martins Barbosa [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil)
2012-07-01
One of the biggest challenges in the drilling of the carbonate rocks of the Pre-salt is to overcome the low penetration rates that have been obtained in the drilling of the reservoir rock in the vertical and directional wells. To overcome this challenge, a great effort is being developed in several lines of research, both in developing new concepts in drill bits and in the selection of a drilling system that together with appropriate type of bit provide an expected improvement in performance. To achieve these results, procedures are being prioritized and drilling systems with lower vibration levels are being used, since this phenomenon of vibration reduces the performance of penetration rate also affecting the lifetime of the equipment and consequently causes a reduction in reliability of all system and raises the cost per meter of drilling. Thus, new drill bit technology and new drilling systems are under development and, among these technologies we can distinguish those that promote improvements in conventional technologies and innovative technologies frankly which uses new mechanisms to cut or weaken the rock. This paper presents an overview of the conventional technology of drilling systems and drill bits, and provides information about the researches that have been developed with the use of innovative technologies which is presented as highly promising, among these innovative technologies, laser drilling and the drilling itself assisted by laser. In this process the laser beam has the main function to weaken the rock improving the rate of penetration. This paper presents a summary of studies and analyzes which are underway to investigate the potential of laser technology, also presents some results of laboratory tests already carried out. The drilling fluid in which the laser will have to pass through in the future applications is analyzed on the approach of their physicochemical properties. Thus, a better understanding of the interaction with the drilling
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New solid laser: Ceramic laser. From ultra stable laser to ultra high output laser
International Nuclear Information System (INIS)
Ueda, Kenichi
2006-01-01
An epoch-making solid laser is developed. It is ceramic laser, polycrystal, which is produced as same as glass and shows ultra high output. Ti 3+ :Al 2 O 3 laser crystal and the CPA (chirped pulse amplification) technique realized new ultra high output lasers. Japan has developed various kinds of ceramic lasers, from 10 -2 to 67 x 10 3 w average output, since 1995. These ceramic lasers were studied by gravitational radiation astronomy. The scattering coefficient of ceramic laser is smaller than single crystals. The new fast ignition method is proposed by Institute of Laser Engineering of Osaka University, Japan. Ultra-intense short pulse laser can inject the required energy to the high-density imploded core plasma within the core disassembling time. Ti 3+ :Al 2 O 3 crystal for laser, ceramic YAG of large caliber for 100 kW, transparent laser ceramic from nano-crystals, crystal grain and boundary layer between grains, the scattering coefficient of single crystal and ceramic, and the derived release cross section of Yb:YAG ceramic are described. (S.Y.)
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LASERTERAPIA NA INFLAMAÇÃO PULMONAR EXPERIMENTAL EM RATTUS NORVEGICUS OCASIONADO PELA PAPAÍNA
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Diego Rodrigues Pessoa
2017-01-01
Full Text Available Resumo: A Doença Pulmonar Obstrutiva Crônica (DPOC é caracterizada pela limitação do fluxo aéreo decorrente da dilatação dos espaços aéreos distais aos bronquíolos terminais. Analisar os efeitos da laserterapia quanto ao processo cicatricial na lesão pulmonar experimental em Rattus Novergicus. Utilizaram-se trinta animais agrupados em três grupos de dez animais: grupo controle (GC (não recebeu nada, grupo DPOC (GD (foi pulverizado 3 doses de papaína 3mg/kg e grupo DPOC + Laser (GDL (após 7 dias da indução da lesão com papaína foi tratado com laser de 660 nm durante 15 dias.Para analise dos resultados foi realizado o lavado broncoalveolar. Quanto ao Lavado: GC (número de células normais, GD (aumento de células inflamatórias e GDL (diminuição de células inflamatórias. A laserterapia diminui o numero de células inflamatórias, entretanto, não possui efeito reconstrutor do parênquima pulmonar apenas estabiliza a lesão comprovando sua ação anti-inflamatória.
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Glycosylation of Vanillin and 8-Nordihydrocapsaicin by Cultured <em>Eucalyptus perrinianaem> Cells
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Naoji Kubota
2012-05-01
Full Text Available Glycosylation of vanilloids such as vanillin and 8-nordihydrocapsaicin by cultured plant cells of <em>Eucalyptus perrinianaem> was studied. Vanillin was converted into vanillin 4-<em>O>-b-D-glucopyranoside, vanillyl alcohol, and 4-<em>O>-b-D-glucopyranosylvanillyl alcohol by <em>E. perriniana em>cells. Incubation of cultured <em>E. perrinianaem> cells with 8-nor- dihydrocapsaicin gave 8-nordihydrocapsaicin 4-<em>O>-b-D-glucopyranoside and 8-nordihydro- capsaicin 4-<em>O>-b-D-gentiobioside.
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Preferencia alimenticia del ácaro depredador <em>Balaustium> sp. en condiciones controladas
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Muñoz Karen
2009-04-01
Full Text Available
Se evaluó la preferencia de presas de <em>Balaustium> sp., enemigo natural de diferentes artrópodos plaga, y el cual es nativo de la Sabana de Bogotá. En unidades experimentales construidas con foliolos de plantas de rosa se colocaron independientemente individuos de <em>Balaustium> sp. y se registró el número de presas consumidas. De esta manera se determinó la preferencia de los tres estados móviles del ácaro depredador <em>Balaustium> sp. por diferentes edades de tres presas. Las especies y edades de las presas estudiadas fueron: huevos, ninfas y adultos de <em>Trialeurodes vaporariorumem>, huevos, ninfas y adultos de <em>Tetranychus urticaeem>, y larvas de primer y segundo instar y adultos de <em>Frankliniella occidentalisem>. Los estados menos desarrollados fueron preferidos, aunque se observó que los adultos del depredador tienen gran habilidad para consumir adultos de <em>T. vaporariorumem>. La presa preferida por las larvas de <em>Balaustium> sp. fue los huevos de <em>T. urticaeem> con una proporción de consumo de 0,54 de los huevos que se ofrecieron de esta presa; las deutoninfas del depredador eligieron huevos de <em>T. vaporariorumem> (0,537 o de <em>T. urticaeem> (0,497 y los adultos de <em>Balaustium> sp. prefrieron los huevos de <em>T. vaporariorumem> (0,588.
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Directory of Open Access Journals (Sweden)
Chunjian Zhao
2012-09-01
Full Text Available Ionic liquid based, ultrasound-assisted extraction was successfully applied to the extraction of phenolcarboxylic acids, carnosic acid and rosmarinic acid, from <em>Rosmarinus officinalisem>. Eight ionic liquids, with different cations and anions, were investigated in this work and [C8mim]Br was selected as the optimal solvent. Ultrasound extraction parameters, including soaking time, solid–liquid ratio, ultrasound power and time, and the number of extraction cycles, were discussed by single factor experiments and the main influence factors were optimized by response surface methodology. The proposed approach was demonstrated as having higher efficiency, shorter extraction time and as a new alternative for the extraction of carnosic acid and rosmarinic acid from <em>R. officinalisem>
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Antioxidant Profile of <em>Trifolium pratenseem> L.
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Heidy Schwartsova
2012-09-01
Full Text Available In order to examine the antioxidant properties of five different extracts of <em>Trifolium pratenseem> L. (Leguminosae leaves, various assays which measure free radical scavenging ability were carried out: 1,1-diphenyl-2-picrylhydrazyl, hydroxyl, superoxide anion and nitric oxide radical scavenger capacity tests and lipid peroxidation assay. In all of the tests, only the H2O and (to some extent the EtOAc extracts showed a potent antioxidant effect compared with BHT and BHA, well-known synthetic antioxidants. In addition, <em>in vivo em>experiments were conducted with antioxidant systems (activities of GSHPx, GSHR, Px, CAT, XOD, GSH content and intensity of LPx in liver homogenate and blood of mice after their treatment with extracts of <em>T. pratenseem> leaves, or in combination with CCl4. Besides, in the extracts examined the total phenolic and flavonoid amounts were also determined, together with presence of the selected flavonoids: quercetin, luteolin, apigenin, naringenin and kaempferol, which were studied using a HPLC-DAD technique. HPLC-DAD analysis showed a noticeable content of natural products according to which the examined <em>Trifolium pratenseem> species could well be regarded as a promising new source of bioactive natural compounds, which can be used both as a food supplement and a remedy.
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Directory of Open Access Journals (Sweden)
Elisângela Barboza da Silva
2013-02-01
Full Text Available OBJETIVO: observar se a laserterapia de baixa intensidade acelera o processo inflamatório, a cicatrização e epitelização de enxertos cutâneos por semeadura. MÉTODOS: vinte ratos foram submetidos a esta técnica de enxertia e divididos em dois grupos iguais, um tratado com laser e outro controle. RESULTADOS: houve menor tempo de reação inflamatória, maior velocidade de cicatrização, epitelização e queratinização nos animais tratados com laser em relação aos não tratados. CONCLUSÃO: a laserterapia de baixa intensidade é efetiva no auxílio ao tratamento de enxertos por semeadura.OBJECTIVE: To observe the effects of low intensity laser therapy in inflammation, wound healing and epithelialization of island skin grafts. METHODS: Twenty rats were subjected to this grafting technique and divided subsequently into two equal groups, one treated with laser and the other control. RESULTS: there was less inflammation, faster healing, epithelialization and keratinization in the laser-treated animals when compared to the untreated. CONCLUSION: Low intensity laser therapy is helpful to island skin grafting.
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Bioassay-Guided Antidiabetic Study of <em>Phaleria macrocarpaem> Fruit Extract
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Mohd Z. Asmawi
2012-04-01
Full Text Available An earlier anti-hyperglycemic study with serial crude extracts of <em>Phaleria macrocarpaem> (PM fruit indicated methanol extract (ME as the most effective. In the present investigation, the methanol extract was further fractionated to obtain chloroform (CF, ethyl acetate (EAF, <em>n>-butanol (NBF and aqueous (AF fractions, which were tested for antidiabetic activity. The NBF reduced blood glucose (<em>p> < 0.05 15 min after administration, in an intraperitoneal glucose tolerance test (IPGTT similar to metformin. Moreover, it lowered blood glucose in diabetic rats by 66.67% (<em>p
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Directory of Open Access Journals (Sweden)
Martha M. Motomo Chojniak
2001-04-01
Full Text Available Objetivo: Vários métodos vem sendo utilizados para o tratamento dos melanomas da coróide. A proposta deste trabalho preliminar é avaliar a eficácia da termoterapia transpupilar (TTT como tratamento primário de melanomas da coróide pequenos. Métodos: Foi realizado um trabalho prospectivo e não-randomizado para avaliar os aspectos clínicos, resposta do tumor, complicações e resultados visuais de pacientes portadores de melanomas da coróide pequenos (até 4,0 mm de espessura e 12 mm de diâmetro basal tratados por termoterapia transpupilar utilizando-se sucessivas aplicações de laser diodo contínuo de 810 nm. Resultados: Foram tratados 11 pacientes portadores de melanomas da coróide pequenos. O tumor era único e pigmentado em 100% dos casos. Crescimento documentado esteve presente em 5 pacientes (45,45% previamente ao tratamento e fatores de risco para crescimento ou metástase estavam presentes em todos os pacientes. O tempo de seguimento destes pacientes a partir do tratamento foi em média de 5,72 meses (3 - 8 meses. Foram utilizadas 3 sessões de laser em 5 pacientes (45,45% e 4 sessões em 6 pacientes (64,64%. As lesões apresentavam, por ocasião do diagnóstico, uma espessura média de 2,65 mm (1,85-3,86 mm, com maior diâmetro basal médio de 7,98 mm (4,2-11,33 mm. Após o tratamento, a espessura média foi de 1,83 mm (0,98-2,93 mm e o maior diâmetro basal médio foi de 6,59 mm (3,81 mm -10,67 mm. Das lesões tratadas, 100% apresentaram diminuição da altura e do máximo diâmetro basal, tendo sido a diminuição média da espessura de 0,89 mm e do máximo diâmetro basal de 1,39 mm. A acuidade visual manteve-se inalterada em 5 casos (45,45% e piorou após o tratamento em 6 casos (54,54%. Ocorreram complicações em 9 casos, tendo sido considerada complicação grave 1 caso de descolamento parcial da retina (9,09%; as outras complicações foram consideradas leves: pequenas hemorragias intra-retinianas em 7 pacientes (63
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Energy Technology Data Exchange (ETDEWEB)
Sousa, Gerdal Roberto de
2001-07-01
The purpose of this study was to evaluate the influence of low intensity laser on the bone repair over periapical lesions of dental elements. Fifteen patients with a total of eighteen periapical lesions were selected and divided into two groups. Lesions of the control group were submitted to endodontic treatment and/or periapical surgery and the lesions of the experimental laser group, were submitted to the same procedures of the first group but also irradiated by low intensity laser. It was used a 904 nm wavelength laser GaAs, employing 11 mW of power delivered by a fiber optic system, irradiation continuos and contact mode, using a fluency of 9 J/cm{sup 2}. The mentioned treatment was repeated for 10 sessions with intervals of 72 hours between each session. Bone repair was evaluated through lesion measurements, which were accessed from the X ray pictures using a time and then, were also statistically analyzed. Results showed a significant difference between lased and control groups (p<0,10), emphasizing that for the laser group presented a significant reduction of the lesions area, confirmed by X ray. (author)
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Alimentazione di <em>Marmota marmotaem> in praterie altimontane delle dolomiti bellunesi
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Alessandro Rudatis
2006-03-01
Full Text Available Abstract The diet of <em>Marmota marmotaem> in the mountain prairie of south-eastern Italian Alps. Diet composition of two family groups of alpine marmots was investigated in two areas of the Agordino’s Dolomites (Italian Alps in June-September 2001, by means of microscopic analysis of faeces and of direct observation of feeding activity. During the whole period of activity, a high consume of Angiosperms was confirmed, especially plants in flower; among them the “graminoids” seemed to play an important role only during the initial part of the active period. Generally vegetative parts predominated over flowers. The ingestion of animal preys was not confirmed by the analysis of droppings. Comparing diet composition of the two groups, Graminaceae (<em>Poa>, <em>Phleum>, Compositae (<em>Achillea>, Cyperaceae/Juncaceae, Leguminosae (<em>Anthyllis>, Rosaceae, and Labiatae (<em>Prunella>, <em>Stachys> formed the bulk of marmot diet in the study areas. Diet showed low diversity considering the abundance of plant species in the surrounding environment. Food resources were probably used in relation to their easy digestibility, with a high content in proteins, sugar and water. The knowledge of vegetation features in relation to marmot trophic habits can represent a useful tool for the management of this species. Riassunto Il regime alimentare di due gruppi di Marmotta alpina è stato studiato in giugno-settembre 2001 in due aree delle Dolomiti agordine (SE Italia, attraverso l’analisi microscopica delle feci e l’osservazione diretta dell’attività alimentare. Durante tutto il periodo di attività si è notato un forte consumo di Angiosperme, specialmente piante a fiore, mentre le ”graminoidi” sembra giochino un ruolo importante all’inizio della stagione. In generale le parti vegetali predominano sui fiori. L’ingestione di prede animali non è stata
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Directory of Open Access Journals (Sweden)
Mariana Marquezan
2013-02-01
Full Text Available INTRODUCTION: Different low-level laser (LLL irradiation protocols have been tested to accelerate orthodontic tooth movement (OTM. Nevertheless, divergent results have been obtained. It was suggested that the stimulatory action of low level laser irradiation occurs during the proliferation and differentiation stages of bone cellular precursors, but not during later stages. OBJECTIVE: The purpose of this study was to determine the effect of two protocols of LLL irradiation on experimental tooth movement: One with daily irradiations and another with irradiations during the early stages. METHODS: Thirty-six rats were divided into control groups (CG1, CG2, CG3 and irradiated groups (IrG1, IrG2, IrG3 according to the presence of: experimental tooth movement, laser irradiation, type of laser irradiation protocol and date of euthanasia (3th or 8th day of experiment. At the end of experimental periods, a quantitative evaluation of the amount of OTM was made and the reactions of the periodontium were analyzed by describing cellular and tissue reactions and by counting blood vessels. RESULTS: The amount of OTM revealed no significant differences between groups in the same experimental period (p INTRODUÇÃO: diferentes protocolos de irradiação por laser de baixa potência (LBP têm sido testados para potencializar o movimento ortodôntico; entretanto, há resultados divergentes. Foi sugerido que seu efeito bioestimulador ocorre nas fases de proliferação e diferenciação celular, não agindo em estágios tardios. OBJETIVO: avaliar o efeito de dois protocolos de irradiação do LBP na movimentação ortodôntica: um com irradiações diárias e outro em que irradiações foram realizadas apenas nos períodos iniciais. MÉTODOS: trinta e seis ratos Wistar foram divididos em grupos controles (GC1, GC2 e GC3 e irradiados (GIr1, GIr2 e GIr3, de acordo com a presença de dispositivo ortodôntico, a presença de irradiação, o tipo de protocolo de irradia
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Directory of Open Access Journals (Sweden)
Tatiana C. Santos
2009-04-01
Full Text Available A distribuição intraparenquimal das veias porta-hepáticas foi estudada em 30 gansos domésticos. Latex Neoprene corado foi injetado pela veia isquiática e os animais forma fixados por imersão e injeção intramuscular com formol a 10% e dissecados. O fígado esteve composto por um grande lobo hepático direito e por um lobo hepático esquerdo menor, os quais estiveram conectados por uma ponte de parênquima. O lobo direito do fígado teve exclusivamente vasos do sistema porta-hepático formados pela distribuição intraparenquimal da veia porta-hepática direita, enquanto que no lobo esquerdo estes originaram-se da veia porta-hepática direita e de pequenas veias porta-hepáticas esquerdas. A veia porta-hepática direita emitiu o ramo caudal direito, que emitiu um pequeno ramo caudolateral direito e um grande ramo caudomedial direito. Cranialmente esta veia emitiu os ramos craniais direito e ramos lateral direito. A porção transversa da veia porta-hepática direita cruzou para o lobo hepático esquerdo, emitindo de 1 a 6 pequenos ramos craniais e caudais para a região média do fígado. No lobo esquerdo, o ramo esquerdo da veia porta-hepática direita emitiu o ramo cranial esquerdo, o ramo lateral esquerdo e o ramo medial. De 1 a 6 veias porta-hepáticas esquerdas foram identificadas desembocando ou no ramo esquerdo da veia porta-hepática direita ou em sua porção transversa, oriundos do ventrículo gástrico e do pró-ventrículo. Em 40% dos gansos uma veia porta-hepática própria oriunda da confluência de vasos venosos da face esquerda do ventrículo distribuiu-se na extremidade caudal do lobo esquerdo isoladamente.The intraparenchymal distribution of the hepatic portal veins in 30 domestic geese were studied. Stained Neoprene latex was injected into the isquiatic vessels, and the animals were fixed in 10% formaldehyde by immersion and intramuscular injection. The liver of geese was composed of a large right and a smaller left
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<em>Ipomoea aquaticaem> Extract Shows Protective Action Against Thioacetamide-Induced Hepatotoxicity
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A. Hamid A. Hadi
2012-05-01
Full Text Available In the Indian system of traditional medicine (Ayurveda it is recommended to consume <em>Ipomoea em>aquatica> to mitigate disorders like jaundice. In this study, the protective effects of ethanol extract of <em>I. aquaticaem> against liver damage were evaluated in thioacetamide (TAA-induced chronic hepatotoxicity in rats. There was no sign of toxicity in the acute toxicity study, in which Sprague-Dawley (SD rats were orally fed with <em>I. aquaticaem> (250 and 500 mg/kg for two months along with administration of TAA (i.p injection 200 mg/kg three times a week for two months. The results showed that the treatment of <em>I. aquaticaem> significantly lowered the TAA-induced serum levels of hepatic enzyme markers (ALP, ALT, AST, protein, albumin, bilirubin and prothrombin time. The hepatic content of activities and expressions SOD and CAT that were reduced by TAA were brought back to control levels by the plant extract supplement. Meanwhile, the rise in MDA level in the TAA receiving groups also were significantly reduced by <em>I. aquaticaem> treatment. Histopathology of hepatic tissues by H&E and Masson trichrome stains displayed that <em>I. aquaticaem> has reduced the incidence of liver lesions, including hepatic cells cloudy swelling, infiltration, hepatic necrosis, and fibrous connective tissue proliferation induced by TAA in rats. Therefore, the results of this study show that the protective effect of <em>I. aquaticaem> in TAA-induced liver damage might be contributed to its modulation on detoxification enzymes and its antioxidant and free radical scavenger effects. Moreover, it confirms a scientific basis for the traditional use of <em>I. aquaticaem> for the treatment of liver disorders.
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Classe social: conceitos e esquemas operacionais em pesquisa em saude
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Rita Barradas Barata
2013-08-01
Full Text Available Discute-se a utilização do conceito de classe em pesquisas em saúde, as diferentes abordagens sociológicas de estratificação social e de estrutura de classes, o potencial explicativo do conceito em estudos de determinação social e desigualdades em saúde, os modelos de operacionalização elaborados para uso em pesquisas sociológicas, demográficas ou de saúde e os limites e possibilidades desses modelos. Foram destacados quatro modelos de operacionalização: de Singer para estudo da distribuição de renda no Brasil, adaptado por Barros para uso em pesquisas epidemiológicas; de Bronfman & Tuirán para o censo demográfico mexicano, adaptado por Lombardi et al para pesquisas epidemiológicas; de Goldthorpe para estudos socioeconômicos ingleses, adaptado pela Sociedade Espanhola de Epidemiologia; e o modelo de Wright para pesquisa em sociologia e ciência política, também usado em inquéritos populacionais em saúde. Em conclusão, conceitualmente cada um dos modelos apresentados é coerente com a concepção teórica que os embasam, mas não há como optar por qualquer deles, descartando os demais.
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UM NOVO MÉTODO PARA CARACTERIZAÇÃO DE PROPRIEDADES MECÂNICAS EM MATERIAIS CERÂMICOS
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Eduardo A. de Carvalho
2010-05-01
Full Text Available As dificuldades de propriedades mecânicas em materiais cerâmicos, seja pela fragilidade intrínseca do material, seja pelo desalinhamento de barras de tração nos métodos tradicionais utilizados para metais, levou à proposição de um novo método de trabalho. O método proposto não se utiliza de contatos mecânicos para a aplicação de carregamento, porém de radiação de uma emissão laser. Aqui é apresentado um caso estudado onde o método determina, com sucesso, a Tenacidade, a Fratura de um corpo de prova em forma de disco feito de nitreto e silício.
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Experimental investigation of linear mode conversion in laser-produced plasmas
International Nuclear Information System (INIS)
Maaswinkel, A.G.M.
1980-12-01
In this work absorption mechanisms are investigated in hot dense plasmas produced by intense laser irradiation of planar targets. Central in this investigation stands the absorption by linear mode conversion; this process occurs in inhomogeneous plasmas if the electric field vector of the incident EM-wave has a component parallel to the density gradient; this causes electrostatic oscillations at the critical density (where ωsub(p)sub(e) = ω). In addition, absorption of the laser light by inverse bremsstrahlung is investigated. The absorption is determined by the reflection of the laser light from the plasma. To this aim optical diagnostics are used. The reflection into 4π sr is measured with an Ulbricht sphere, also the reflection in specular (geometric) direction is recorded. The absorption mechanisms have been isolated by variation of the polarization of the beam and the angle of incidence to the target. An essential part of the work has been the frequency up-conversion of the laser beam by nonlinear crystals; in this way the wavelength-dependence of the absorption in the plasma has been investigated at wavelengths 1.06 μm, 0.53 μm and 0.26 μm; the pulse duration in the experiments was 30 ps, the maximum irradiation on target was 10 14 W/cm 2 . (orig./HT)
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Vaporização a laser do cervix para tratamento da neoplasia intraepitelial cervical
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Euridice Maria de Almeida Figueiredo
Full Text Available O câncer cérvico-uterino é muito comum em vários países da América Latina. As estatísticas de mortalidade e as taxas de incidência demonstram a sua real importância. O cânver cérvico-uterino freqüentemente é uma doença progressiva iniciada com mudanças intra-epiteliais, que podem se transformar em um processo invasivo, sendo o nosso objetivo tratar precocemente estas lesões quando ainda é possível a cura de 100%. Em nosso estudo prospectivo foram selecionadas 21 pacientes com neoplasia cervical intra-epitelial reatreadas pela citplogia e diagnosticadas pela histopatologia após biópsia dirigida pela colposcopia. O método terapêutico empregado foi a vaporização a laser com o CO2. Tiveram como pré-requisito os seguintes critérios: informação segura pela colposcopia da zona de transformação e afastar a presença de câncer invasivo; a neoplasia epitelial cervical deve ocupar a ectocervix sem nenhuma extensão para o canal cervical e correlação positiva entre a citologia, colposcopia e histologia. O uso de laser CO2 com microscópio permitiu precisão na aplicação e com vantagens de ser um procedimento ambulatorial diminuindo estresse cirúrgico das pacientes. Foi realizado sem anestesia e com duração média de 15 minutos. A cicatrização completou-se em torno de três semanas e com cuidados operatórios mínimos. Somente dois casos tiveram sangramento vaginal discreto no quinto e décimo dia de pós-operatório, resolvido com tamponamento vaginal por 24 horas. A colposcopia, cirurgia e o seguimento foram feitos pelo autor, tendo uma paciente sido submetida a uma segunda vaporização no quinto mês de controle. Somente uma paciente teve recidiva no 26° mês de seguimento e complementará o tratamento. As vinte outras restantes estão em controle sem recidiva de doença. Em vista dos resultados obtivemos um percentual de cura de 95%, que coincide com a literatura. O uso de laser CO2 no tratamento das neoplasias
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Laser-diode pumped Nd:YAG lasers; Laser diode reiki Nd:YAG lasear
Energy Technology Data Exchange (ETDEWEB)
Yuasa, H.; Akiyama, Y.; Nakayama, M. [Toshiba Corp., Tokyo (Japan)
2000-04-01
Laser-diode pumped Nd:YAG lasers are expected to be applied to laser processing fields such as welding, cutting, drilling, and marking due to their potential for high efficiency and compactness. We are designing and developing laser-diode pumped Nd:YAG lasers using numerical analysis simulation techniques such as ray tracing and thermal analysis. We have succeeded in achieving a laser power of more than 3 kW with 20% efficiency, which is the best ever obtained. In addition, we have developed a laser-diode pumped green laser by second harmonic generation, for precision machining on silicon wafers. (author)
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Directory of Open Access Journals (Sweden)
Marco Cantini
1991-07-01
Full Text Available Abstract The diet of the fox was investigated by analysis of 273 scats, collected along standard trails from April to November 1987 and 1988. Food habits of foxes were described for three altitudinal ranges. Mammals, mainly <em>Clethrionomys glareolusem> and <em>Microtus multiplexem>, were the staple food (percentage of frequency 42.8%, followed by fruits and other vegetables (26.7% and 37.3% respectively. Birds, Invertebrates (mainly Insects and garbage were little eaten. The game species (ungulates, hares, pheasants occurred with a low frequency (8.4% in the diet. The trophic niche breadth varied little through the altitudinal ranges and the seasons. The trophic niche overlap between the fox and the genus <em>Martes> (190 scats of <em>M. martesem> and <em>M. foinaem> were examined is relatively wide (O=0.868. Riassunto La dieta della Volpe (<em>Vulpes vulpesem> in aree boscate delle Alpi Orobie (Val Lesina è stata indagata nel periodo aprile-novembre 1987 e 1988 mediante l'analisi di 273 feci, raccolte lungo percorsi-campione ricadenti in tre piani vegetazionali. I Mammiferi, in particolare <em>Clethrionomys glareolusem> e <em>Microtus multiplexem>, sono la componente principale della dieta (frequenza percentuale 42,8%. Rilevante è anche il consumo di frutti (soprattutto in estate e autunno e di altri vegetali (26,7% e 37,3% rispettivamente, mentre poco frequente è quello di Uccelli, Invertebrati e rifiuti. Complessivamente ridotta è l'azione predatoria della Volpe nei confronti delle specie di interesse venatorio (Ungulati, lepri, Galliformi. L'ampiezza della nicchia trofica mostra modeste variazioni stagionali e altitudinali. I1 grado di sovrapposizione tra la nicchia trofica della Volpe e quella del genere <em>Martes>, quest'ultima ricavata dall'analisi di 190 feci di Martora (<em>M. martesem> e Faina (<em>M. foinaem>, è elevato (O=0,868. Tuttavia, poiché in condizioni di
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Directory of Open Access Journals (Sweden)
Gianna Dondini
2003-10-01
Full Text Available Molte specie di pipistrelli delle fasce climatiche temperato-fredde sono soggette a marcate variazioni stagionali di temperatura e disponibilità di cibo. L'accumulo di grasso in autunno è quindi un adattamento per trascorrere, in uno stato di profondo torpore definibile ibernazione, i mesi invernali, aumentando così la probabilità di sopravvivenza durante tale periodo. Nell?ambito di una attività pluriennale relativa alla raccolta, studio e, quando possibile, riabilitazione di pipistrelli in ambienti urbani, due esemplari di <em>Pipistrellus kuhliiem> (2 femmine e due di <em>Hypsugo saviiem> (1 maschio e 1 femmina, in entrambi casi giovani che ancora non avevano acquisito una sufficiente capacità nel volo e quindi non liberabili, sono stati raccolti nella pianura di Firenze durante l?estate del 1998 e mantenuti in condizioni di temperatura ambientale oscillante tra i 17 e i 22°C, in un contenitore di 150x40x30 cm. Ogni sera sono stati pesati, prima della somministrazione di cibo e acqua, con una bilancia elettronica con precisione di 0.1 g (modello Tanita 1479. L'alimentazione è stata a base di vermi della farina (<em>Tenebrio molitorem>. L?efficienza digestiva è calcolata nel seguente modo, su materiale disidratato: (quantità ingerita ? quantità escrementi/quantità ingerita*100. Per il calcolo di tale indice gli esemplari delle due specie sono stati separati e mantenuti per 24 ore a partire dalla successiva sera dell?ultima somministrazione, favorendo così lo svuotamento dell?intestino. Successivamente, per due giorni è stato fornito del cibo <em>ad libitumem>, pesando i singoli esemplari una volta terminata la fase di alimentazione, per determinare la quantità ingerita. Al termine abbiamo mantenuto gli esemplari a digiuno per 24 ore successive all?ultima somministrazione per permettere lo svuotamento dell?intestino. Gli escrementi raccolti sono stati posti in forno elettrico a 90 °C per 24 ore e successivamente pesati
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Directory of Open Access Journals (Sweden)
Xiangzheng Deng
2012-06-01
Full Text Available Bioenergy is currently regarded as a renewable energy source with a high growth potential. Forest-based biodiesel, with the significant advantage of not competing with grain production on cultivated land, has been considered as a promising substitute for diesel fuel by many countries, including China. Consequently, extracting biodiesel from <em>Jatropha
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Directory of Open Access Journals (Sweden)
Bradley M. Freeman
2011-12-01
Full Text Available
Despite almost a hundred years of separation, both Cecil B. DeMille’s film <em>The Cheatem> (1915 and John Updike’s novel <em>Terrorist> (2006 deploy a clear-cut territorial divide between Western and Eastern spaces in order to envision a unified American space. These narratives superimpose a “natural” division on these historically opposed spaces and thereby suggest that any contact between these spaces will have dangerous consequences. These consequences include the potential dissolution and eventual destruction of American productivity, surveillance, and territorial integrity. DeMille’s film and Updike’s novel represent America as a nation-state that must be protected from the East. In 1915, <em>The Cheatem> warned against an interracial America and the upsurge in immigration that characterized the turn of the century. Nearly a century later, <em>Terrorist> presupposes an interracial America but still constructs an East that threatens the security of America. While registering the particular concerns of two distinct historical moments, these narratives represent a larger attempt in American aesthetics to imagine an East that jeopardizes the utopian possibilities of an overly idealized American space.
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<em>In Vitro em>Phytotoxicity and Antioxidant Activity of Selected Flavonoids
Directory of Open Access Journals (Sweden)
Rita Patrizia Aquino
2012-05-01
Full Text Available The knowledge of flavonoids involved in plant-plant interactions and their mechanisms of action are poor and, moreover, the structural characteristics required for these biological activities are scarcely known. The objective of this work was to study the possible <em>in vitro em>phytotoxic effects of 27 flavonoids on the germination and early radical growth of <em>Raphanus sativus em>L.> and <em>Lepidium sativumem> L., with the aim to evaluate the possible structure/activity relationship. Moreover, the antioxidant activity of the same compounds was also evaluated. Generally, in response to various tested flavonoids, germination was only slightly affected, whereas significant differences were observed in the activity of the various tested flavonoids against radical elongation. DPPH test confirms the antioxidant activity of luteolin, quercetin, catechol, morin, and catechin. The biological activity recorded is discussed in relation to the structure of compounds and their capability to interact with cell structures and physiology. No correlation was found between phytotoxic and antioxidant activities.
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Energy Technology Data Exchange (ETDEWEB)
Camargo, Fabiola de Almeida
2006-07-01
Within the existing variety of laser cavity geometries and gain materials there is one combination that is particularly interesting because of its reduced complexity and high efficiency: the edge-pumped slab-laser using grazing-incidence geometry and a gain media with a very high pump absorption cross-section. In this work we studied a diode side-pumped Nd:YVO{sub 4} cw laser. We describe a single and a multiple bounce laser configurations. We demonstrate 22 W of multimode output power for 35 watts of pump power with a single pass through the gain media. A high optical-to-optical conversion efficiency of 63% and a slope efficiency of 74% with a very compact and simple Nd:YVO{sub 4} cavity that uses joint stability zones was achieved. The beam quality was M{sup 2} = 26 x 11 in the horizontal and vertical direction, respectively. With a double pass configuration we achieved 17 watts with a better beam quality of M{sup 2} = 3,4 x 3,7, in the horizontal and vertical direction, respectively. (author)
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Energy Technology Data Exchange (ETDEWEB)
Amorim, Jose Claudio Faria
2001-07-01
For the present study seven patients presenting periodontal disease were selected in a way that they required the performance of gingivectomy procedure in the region of premolars in both sides, being this in the upper or lower region. After the surgical procedure one side was submitted to low intensity laser radiation, wavelength 685 nm, power 50 mW and fluency of 4J/cm{sup 2}, contact mode. The other side was used as a control, not receiving any laser irradiation. Healing process for both sides, was clinically and biometrically evaluated and compared using photographs for the periods: pre-operative, immediate post-operative, 3, 7,14,21, 28 and 35 days. The analysis was performed by 3 specialists in Periodontology considering aspects of healing. Results were submitted to statistical analysis. Biometrical evaluation showed improvement of healing for the period of 21 and 28 days in the lased group. Clinical evaluation showed better reparation mainly after the third day for the active group. Laser group was considered to present an improved healing when compared to the control group. (author)
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Energy Technology Data Exchange (ETDEWEB)
Nogueira, Alessandro Francelino
2015-07-01
The texturing laser micromachining is an important alternative to improve the bonding adhesion between composites and titanium, which are applied to structural components in the aerospace industry. The texturing running on titanium plates is due to the fact that the preferred joining technique for many composite materials is the adhesive bonding. In this work, titanium plates were texturized using laser ultrashort pulses temporal widths of femtoseconds. This process resulted in minimal heat transfer to the material, avoiding deformation of the titanium plate surface as well as the formation of resolidified material in the ablated region. These drawbacks have occurred with the use of nanoseconds pulses. Were performed three types of texturing using laser with femtosecond pulses, with variations in the distances between the machined lines. The analysis of the obtained surfaces found that the wettability increases when there is the increased distance between the texturing lines. Advancing in the analysis by optical profilometry of textured surfaces was observed that there is substantial increase in the volume available for penetration of structural adhesive when the distances between the textured lines are diminished. In tensile tests conducted it was observed that there is an increase in shear strength of the adhesive joint by reducing the distance between the textured lines. (author)
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International Nuclear Information System (INIS)
Harris, D.G.; Shay, T.M.
1990-01-01
This book covers the following topics: XUV, X-Ray and Gamma-Ray Lasers, excimer lasers, chemical lasers, nuclear pumped lasers, high power gas lasers, solid state lasers, laser spectroscopy. The paper presented include: Development of KrF lasers for fusion and Nuclear driven solid-state lasers
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Busca de estruturas em grandes escalas em altos redshifts
Boris, N. V.; Sodré, L., Jr.; Cypriano, E.
2003-08-01
A busca por estruturas em grandes escalas (aglomerados de galáxias, por exemplo) é um ativo tópico de pesquisas hoje em dia, pois a detecção de um único aglomerado em altos redshifts pode por vínculos fortes sobre os modelos cosmológicos. Neste projeto estamos fazendo uma busca de estruturas distantes em campos contendo pares de quasares próximos entre si em z Â3 0.9. Os pares de quasares foram extraídos do catálogo de Véron-Cetty & Véron (2001) e estão sendo observados com os telescópios: 2,2m da University of Hawaii (UH), 2,5m do Observatório de Las Campanas e com o GEMINI. Apresentamos aqui a análise preliminar de um par de quasares observado nos filtros i'(7800 Å) e z'(9500 Å) com o GEMINI. A cor (i'-z') mostrou-se útil para detectar objetos "early-type" em redshifts menores que 1.1. No estudo do par 131046+0006/J131055+0008, com redshift ~ 0.9, o uso deste método possibilitou a detecção de sete objetos candidatos a galáxias "early-type". Num mapa da distribuição projetada dos objetos para 22 escala. Um outro argumento em favor dessa hipótese é que eles obedecem uma relação do tipo Kormendy (raio equivalente X brilho superficial dentro desse raio), como a apresentada pelas galáxias elípticas em z = 0.
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Directory of Open Access Journals (Sweden)
Johan O. Westman
2012-09-01
Full Text Available The ability of macroencapsulated <em>Saccharomyces cerevisiae em>CBS8066<em> em>to withstand readily and not readily <em>in situem> convertible lignocellulose-derived inhibitors was investigated in anaerobic batch cultivations. It was shown that encapsulation increased the tolerance against readily convertible furan aldehyde inhibitors and to dilute acid spruce hydrolysate, but not to organic acid inhibitors that cannot be metabolized anaerobically. Gene expression analysis showed that the protective effect arising from the encapsulation is evident also on the transcriptome level, as the expression of the stress-related genes <em>YAP1em>, <em>ATR1em> and <em>FLR1em> was induced upon encapsulation. The transcript levels were increased due to encapsulation already in the medium without added inhibitors, indicating that the cells sensed low stress level arising from the encapsulation itself. We present a model, where the stress response is induced by nutrient limitation, that this helps the cells to cope with the increased stress added by a toxic medium, and that superficial cells in the capsules degrade convertible inhibitors, alleviating the inhibition for the cells deeper in the capsule.
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Laser safety at high profile laser facilities
International Nuclear Information System (INIS)
Barat, K.
2010-01-01
Complete text of publication follows. Laser safety has been an active concern of laser users since the invention of the laser. Formal standards were developed in the early 1970's and still continue to be developed and refined. The goal of these standards is to give users guidance on the use of laser and consistent safety guidance and requirements for laser manufacturers. Laser safety in the typical research setting (government laboratory or university) is the greatest challenge to the laser user and laser safety officer. This is due to two factors. First, the very nature of research can put the user at risk; consider active manipulation of laser optics and beam paths, and user work with energized systems. Second, a laser safety culture that seems to accept laser injuries as part of the graduate student educational process. The fact is, laser safety at research settings, laboratories and universities still has long way to go. Major laser facilities have taken a more rigid and serious view of laser safety, its controls and procedures. Part of the rationale for this is that these facilities draw users from all around the world presenting the facility with a work force of users coming from a wide mix of laser safety cultures. Another factor is funding sources do not like bad publicity which can come from laser accidents and a poor safety record. The fact is that injuries, equipment damage and lost staff time slow down progress. Hence high profile/large laser projects need to adapt a higher safety regimen both from an engineering and administrative point of view. This presentation will discuss all these points and present examples. Acknowledgement. This work has been supported by the University of California, Director, Office of Science.
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Directory of Open Access Journals (Sweden)
Igor Pavlinić
2008-07-01
Full Text Available Abstract After the discovery of two different phonic types within the common pipistrelle (<em>Pipistrellus pipistrellusem>, mtDNA analysis confirmed the existence of two separate species named as common pipistrelle (<em>P. pipistrellusem> and soprano pipistrelle (<em>P. pygmaeusem>. The discrimination of these two cryptic species using external characters and measures has proved to be somewhat problematic. We examined two colonies of soprano pipistrelle from Donji Miholjac, Croatia. As a result, only two characters proved to be of help for field identification: wing venation (89% of cases and penis morphology and colour for males. The difference in length between the 2nd and 3rd phalanxes of the 3rd finger should be discarded as diagnostic trait between <em>P. pipistrellusem> and <em>P. pygmaeusem> in Croatia. Riassunto Identificazione su basi morfologiche del pipistrello pigmeo (<em>Pipistrellus pygmeausem>, Leach, 1825 in Croazia. A seguito della descrizione di due differenti "tipi fonici" nel pipistrello nano (<em>Pipistrellus pipistrellusem> e della successiva conferma su basi genetiche dell'esistenza di due specie distinte, designate come pipistrello nano (<em>P. pipistrellusem> e pipistrello pigmeo (<em>P. pygmaeusem>, la distinzione delle due specie in base a caratteristiche morfologiche esterne si è dimostrata un problema di difficile soluzione. Sulla base delle caratteristiche distintive e delle differenze biometriche proposte da altri Autori, sono state esaminate due colonie di pipistrello pigmeo a Donji Miholjac, in Croazia. I risultati ottenuti evidenziano che, tra tutti i potenziali caratteri sinora proposti, solo due risultano utili per un'identificazione diretta sul campo: la venatura delle ali, risultata utile alla discriminazione nell'89% degli esemplari analizzati, e la colorazione e morfologia del pene nei maschi. La
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Directory of Open Access Journals (Sweden)
Krzysztof Piksa
2006-03-01
Full Text Available Riassunto Distribuzione altitudinale di Orecchione bruno (<em>Plecotus auritusem> e Orecchione meridionale (<em>Plecotus austriacusem> nei Monti Tatra (Polonia meridionale. Vengono riportati nuovi dati relativi alla distribuzione altitudinale nei Monti Tatra (Polonia meridionale di <em>Plecotus auritusem> e <em>P. austriacusem>. Tali segnalazioni incrementano le conoscenze relative alla presenza di questi chirotteri a quote elevate, in particolare per la Polonia. In inverno <em>P. auritusem> è stato rinvenuto a 1921 m s.l.m. mentre in estate è stato rinvenuto a 2250 m s.l.m.; in aggiunta, sono stati ritrovati resti ossei a 1929 m s.l.m. <em>P. austriacusem> è stato segnalato in ibernazione a 1294 m s.l.m.
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Directory of Open Access Journals (Sweden)
Yanli Wang
2012-06-01
Full Text Available The antibacterial activity and mechanism of two kinds of chitosan were investigated against twelve <em>Xanthomonas> strains recovered from <em>Euphorbia pulcherrimaem>. Results indicated that both chitosans markedly inhibited bacterial growth based on OD loss. Furthermore, the release of DNA and RNA from three selected strains was increased by both chitosans. However, the release of intracellular proteins was inhibited by both chitosans at different concentration and incubation times, except chitosan A at 0.1 mg/mL for 0.5 h incubation and 0.2 mg/mL for 2.0 h incubation increased the release of proteins, indicating the complexity of the interaction and cell membranes, which was affected by incubation time, bacterial species, chitosan type and concentration. Transmission electron microscopic observations revealed that chitosan caused changes in protoplast concentration and surface morphology. In some cells, the membranes and walls were badly distorted and disrupted, while other cells were enveloped by a thick and compact ribbon-like layer. The contrary influence on cell morphology may explain the differential effect in the release of material. In addition, scanning electron microscope and biofilm formation test revealed that both chitosans removed biofilm biomass. Overall, this study showed that membrane and biofilm play an important role in the antibacterial mechanism of chitosan.
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Directory of Open Access Journals (Sweden)
Nawal M. Al-Musayeib
2012-09-01
Full Text Available The present study investigated the <em>in vitroem> antiprotozoal activity of sixteen selected medicinal plants. Plant materials were extracted with methanol and screened <em>in vitroem> against erythrocytic schizonts of <em>Plasmodium falciparumem>, intracellular amastigotes of <em>Leishmania infantum em>and <em>Trypanosoma cruzi em>and free trypomastigotes of<em> T. bruceiem>. Cytotoxic activity was determined against MRC-5 cells to assess selectivity<em>. em>The criterion for activity was an IC50 < 10 µg/mL (4. Antiplasmodial activity was found in the<em> em>extracts of<em> em>
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Directory of Open Access Journals (Sweden)
Patricia Ramos Lloret
2004-09-01
Full Text Available The use of argon laser (488 nm has been suggested as a new alternative for polymerizing adhesive materials. This study aimed to evaluate the tensile bond strength of a microfilled composite (A110, 3M inserted by incremental technique (3 increments of 1 mm and by single increment (3 mm polymerized by argon laser for 10, 20 and 30 seconds and halogen light for 40 seconds. Eighty (8 groups of 10 teeth freshly extracted bovine teeth were stored in a freezer in distilled water for one week. The crowns were cross-sectioned from the roots. Pulpectomy was performed and the pulp chambers were sealed with wax. The buccal surfaces of the teeth were ground with wet sandpaper (grains: 120, 400, and 600 to expose the surface dentin, and the teeth were then included in acrylic resin. A metal device was used to fix each sample and a black propylene matrix25 (3 mm high with an internal millimetric delimitation was used to insert the material according to the groups studied. The polymerization intervals were of 10, 20 and 30 seconds for the laser polymerization and 40 seconds for the conventional polymerization. Tensile tests were performed by a Universal Testing Machine 4442 (Instron at a speed of 0.5 mm/min and 500 N load. According to the methodology used, the incremental technique increased bond strength values. There was no difference between the studied polymerization techniques when resin was filled in 3 increments.O uso do laser de argônio (488 nm tem sido sugerido como uma nova alternativa para polimerização de materiais adesivos. Este estudo tem o objetivo de avaliar a resistência adesiva de uma resina composta microparticulada (A110, 3M inserida pela técnica incremental (3 incrementos de 1 mm e de incremento único (3 mm polimerizada com laser de argônio por 10, 20 e 30 segundos e com luz halógena por 40 segundos. Oitenta (8 grupos com 10 dentes dentes bovinos recém-extraídos foram armazenados em geladeira, em água destilada, por uma semana
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Directory of Open Access Journals (Sweden)
Cubillos-Hinojosa Juan
2009-04-01
Full Text Available
Se realizó un experimento en condiciones de laboratorio e invernadero, con el propósito de evaluar el efecto de la cepa nativa TCN-014 y la cepa comercial TCC-005 de <em>Trichoderma harzianumem> sobre la germinación y el crecimiento temprano del maracuyá. Se adecuaron inóculos de 104, 106 y 108 conidias/mL para cada cepa y se aplicaron a semillas de maracuyá; se evaluó el número de semillas germinadas durante 15 días; se calculó el porcentaje de germinación, el índice de velocidad de germinación y el tiempo medio de germinación. Posteriormente las semillas germinadas se llevaron a condiciones de invernadero y transcurridos dos meses se midió la altura de las plántulas, el grosor del tallo, el número de hojas, la longitud de la raíz y el peso seco total. Todos los tratamientos estimularon la germinación de las semillas y el desarrollo de las plántulas; sin embargo la cepa nativa en concentraciones 106 y 108 conidias/mL mostró resultados superiores frente a la cepa comercial. Los resultados sugieren una acción efectiva de <em>T. harzianumem> como promotor de crecimiento vegetal, mostrando que tiene potencial para la elaboración de un bioproducto útil para el manejo ecológico del cultivo de maracuyá.
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EFEITO AGUDO DO LASER DE BAIXA POTÊNCIA NA FADIGA DO BÍCEPS BRAQUIAL DE ATLETAS DE VOLEIBOL
Directory of Open Access Journals (Sweden)
Juliana Lôbo Froio
Full Text Available RESUMO Introdução: A laserterapia de baixa potência tem entre seus propósitos auxiliar a recuperação de tecidos biológicos, atenuando os efeitos da fadiga muscular e contribuindo com a melhora do desempenho em atletas. Aspectos metodológicos ainda limitam as conclusões do efeito agudo da laserterapia sobre o desempenho muscular. Objetivo: Verificar o efeito agudo do laser terapêutico de baixa potência na fadiga induzida do bíceps braquial de atletas de voleibol. Métodos: Este foi um estudo randomizado e duplo-cego, aprovado pelo Comitê de Ética da UNESP de Marília. Participaram do estudo 19 atletas de voleibol de ambos os sexos. Realizou-se coleta de dados eletromiográficos do músculo bíceps braquial no exercício isométrico de flexão de cotovelo antes e após a aplicação do laser terapêutico. Um haltere com 75% do pico de força, obtido por uma célula de carga, foi utilizado para o protocolo de fadiga. Em seguida, os voluntários foram submetidos à aplicação do laser (ativo ou placebo em seis pontos do músculo bíceps braquial. Os dados eletromiográficos foram analisados no domínio da frequência, utilizando-se o software Myosystem®. Verificou-se a distribuição de normalidade dos dados pelo teste de Shapiro-Wilk, e utilizou-se Anova (split plot de medidas repetidas a fim de testar a interação entre tempo e grupo. Resultados: Para nenhuma das variáveis analisadas foi observada interação significativa entre grupo e tempo, indicando que o grupo irradiado não apresentou vantagens com relação ao grupo placebo. Conclusão: Após o protocolo de fadiga proposto, uma única aplicação de laser de baixa potência não foi suficiente para produzir efeitos positivos no desempenho de força e no sinal eletromiográfico do músculo bíceps braquial de atletas de voleibol.
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Experimental and theoretical study of the electron cascade induced in a gas by laser light
International Nuclear Information System (INIS)
Louis-Jacquet, Michel.
1978-10-01
In a laser gas interaction experiment, first electrons created by multiphoton ionization of atoms gain sufficient energy in the laser E.M. wave to promote collisional ionization of other atoms. An experimental and theoretical study of the electron-neutral atom inverse bremsstrahlung process and the consecutive electron cascade is presented. The main basic idea is to create an initial electron population and to study its evolution versus the photon density. A Boltzman equation including several collision terms can describe such a plasma. The resolution by a general eigen values method shows that the electron density growth rate is inversely proportionnal to both neutral atom density and laser light illumination. Experimental conditions were defined in order to insure negligible secondary mechanisms (multiphoton ionization, diffusion, recombination, ...). Using a macroscopic description of the interaction, the growth rate can be deduced from the experimental results. Values are in a rather good agreement with the theoretical ones. Moreover evidence is given of influence of the excited atoms on the multiplication process [fr
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Laser in urology. Laser i urologien
Energy Technology Data Exchange (ETDEWEB)
Breisland, H.O. (Aker Sykehus, Oslo (Norway))
1991-09-01
The neodymium YAG laser is particularly suited for endoscopic urologic surgery because the YAG laser light can be conducted in flexible fibers. Superficial bladder tumours can be treated under local anaesthesia in the outpatient department. The frequency of local recurrences is low, significantly lower than after electrosection or electrocoagulation. Selected cases of T2-muscle invasive bladder tumours can be cured with laser coagulation applied subsequently to transurethral resection. Combined treatment with electrosection and laser coagulation of localized prostatic cancer is a promising method which compares favourably with results obtained by other treatment modalities. Tumours in the upper urinary tract can be laser-treated through ureteroscopes or nephroscopes, but the treatment should be limited to low stage, low grade tumours. Laser is the treatment of choice for intraurethral condylomatas. Laser treatment of penil carcinoma gives excellent cosmetic and functional results and few local recurrences. Laser lithotripsy is a new technique for treatment of ureteric stones and photodynamic laser therapy is a promising tecnique for treatment of carcinoma in situ in the bladder empithelium. However, neither of these techniques are available for clinical use in Norway as yet. 17 refs., 3 figs., 1 tabs.
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Directory of Open Access Journals (Sweden)
Alexandre Marcio Marcolino
2010-01-01
Full Text Available OBJETIVO: Avaliar o efeito do laser de baixa intensidade na melhora funcional da marcha de ratos após esmagamento do nervo ciático. MÉTODOS: Foram utilizados 18 ratos divididos alea-to-riamente em dois grupos: controle (sham e irradiado com densidade de energia de 40J/cm², em 21 dias consecutivos, utilizando o laser 830nm (AsGaAl. Os animais foram submetidos ao esmagamento do nervo ciático direito com o dispositivo portátil de peso morto e avaliados pelo "Índice Funcional do Ciático" (IFC. As pegadas foram coletadas no pré-operatório, 7º, 14º e 21º dias pós-operatório. RESULTADOS: Os resultados do IFC foram significantes quando comparados os grupos no 7º e 14º dia pós-operatório (pOBJECTIVE: This study aimed to evaluate the effect of low-intensity laser on functional improvement of the walking of rats after sciatic nerve axonotmesis. METHODS: We used 18 rats divided randomly in two groups: control (Sham and irradiated with an energy density of 40J/cm² for 21 consecutive days, using 830nm laser (AsGaAl. The animals were subjected to right sciatic nerve crushing by a portable device and assessed by the "Sciatic Functional Index" (SFI at an acrylic platform through video recorded by a digital camera. The footprints were collected preoperatively, and on the 7th, 14th and 21st postoperative days. RESULTS: The results of the SFI were significant when comparing the groups on the 7th and 14th postoperative day (p<0.05. On the 21st postoperative day there was no difference between groups. There were intra-group differences detected in each evaluated week (p<0.01. The irradiated animals showed improvement in motion pattern, shown by the SFI values in the initial periods, but after 3 weeks, there was a similar recovery. CONCLUSION: The low-intensity laser has shown to be effective in accelerating regeneration of the sciatic nerve of rats after crushing.
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Directory of Open Access Journals (Sweden)
Adriene Mara Souza Lopes-Silva
2003-09-01
Full Text Available The purpose of this study was to evaluate in vitro the dentin permeability of the deciduous pulp chamber floor after employing 2-octyl cyanoacrylate and Er:YAG laser. Twenty four deciduous molars were used, divided into four groups. After chemical-surgical preparation each group received a different treatment: Group 1 - control, without treatment; Group 2 - the floor of the pulp chamber was covered with a fine layer of 2-octyl cyanoacrylate; Group 3 - the floor of the pulp chamber was irradiated with Er:YAG laser (250 mJ, 10 Hz for 30 seconds, 80 J of energy and 320 pulses, and covered with a fine layer of 2-octyl cyanoacrylate; and Group 4 - the floor of the pulp chamber was irradiated with Er:YAG laser set at the parameters already described. After that the specimens received application of 0.5% methylene blue, for 15 minutes. The teeth were cut, photographed, and the digitalized images were analyzed using the ImageLab program. The results obtained were submitted to statistical analysis. Group 4 (Er:YAG presented the largest averages in percentage of dye penetration area (19.5%, followed by Group 1 (11.1%, Group 3 (1.4% and Group 2 (0.2%. The experimental model allowed to conclude that the specimens conditioned with 2-octyl cyanoacrylate (Group 2 and Er:YAG laser associated to 2-octyl cyanoacrylate (Group 3 presented a decrease in permeability, and the specimens treated with Er:YAG laser (Group 4 presented an increase in permeability of the analyzed area.A proposta do presente experimento foi avaliar in vitro a permeabilidade da dentina no assoalho da câmara pulpar de dentes decíduos com o emprego do 2-octil cianoacrilato e laser de Er:YAG. Foram empregados 24 molares decíduos, divididos em quatro grupos. Após preparo químico-cirúrgico, cada grupo recebeu um tratamento diferente: Grupo 1 - controle, sem tratamento; Grupo 2 - o assoalho da câmara pulpar foi coberto com uma fina camada de 2-octil cianoacrilato; Grupo 3 - o assoalho da c
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Directory of Open Access Journals (Sweden)
Ting Feng
2012-07-01
Full Text Available In traditional Chinese medicine, shikonin and its derivatives, has been used in East Asia for several years for the prevention and treatment of several diseases, including cancer. We previously identified that β,β-dimethylacrylshikonin (DA could inhibit hepatocellular carcinoma growth. In the present study, we investigated the inhibitory effects of DA on human colorectal cancer (CRC cell line HCT-116 <em>in vitroem> and <em>in vivoem>. A viability assay showed that DA could inhibit tumor cell growth in a time- and dose-dependent manner. Flow cytometry showed that DA blocks the cell cycle at G0/G1 phase. Western blotting results demonstrated that the induction of apoptosis by DA correlated with the induction of pro-apoptotic proteins Bax, and Bid, and a decrease in the expression of anti-apoptotic proteins Bcl-2 and Bcl-xl. Furthermore, treatment of HCT-116 bearing nude mice with DA significantly retarded the growth of xenografts. Consistent with the results <em>in vitroem>, the DA-mediated suppression of HCT-116 xenografts correlated with Bax and Bcl-2. Taken together, these results suggest that DA could be a novel and promising approach to the treatment of CRC.
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Yuangang Zu
2012-07-01
Full Text Available In order to screen a suitable resin for the preparative simultaneous separation and purification of syringin, eleutheroside E and isofraxidin from <em>Acanthopanax> <em>senticosus>, the adsorption and desorption properties of 17 widely used commercial macroporous resins were evaluated. According to our results, HPD100C, which adsorbs by the molecular tiers model, was the best macroporous resin, offering higher adsorption and desorption capacities and higher adsorption speed for syringin, eleutheroside E and isofraxidin than other resins. Dynamic adsorption and desorption tests were carried out to optimize the process parameters. The optimal conditions were as follows: for adsorption, processing volume: 24 BV, flow rate: 2 BV/h; for desorption, ethanol–water solution: 60:40 (v/v, eluent volume: 4 BV, flow rate: 3 BV/h. Under the above conditions, the contents of syringin, eleutheroside E and isofraxidin increased 174-fold, 20-fold and 5-fold and their recoveries were 80.93%, 93.97% and 93.79%, respectively.
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Training for Defense? From Stochastic Traits to Synchrony in Giant Honey Bees (<em>Apis dorsataem>
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Gerald Kastberger
2012-08-01
Full Text Available In Giant Honey Bees, abdomen flipping happens in a variety of contexts. It can be either synchronous or cascaded, such as in the collective defense traits of shimmering and rearing-up, or it can happen as single-agent behavior. Abdomen flipping is also involved in flickering behavior, which occurs regularly under quiescent colony state displaying singular or collective traits, with stochastic, and (semi- synchronized properties. It presumably acts via visual, mechanoceptive, and pheromonal pathways and its goals are still unknown. This study questions whether flickering is preliminary to shimmering which is subject of the <em>fs em>(flickering-shimmering-transition> hypothesis? We tested the respective prediction that trigger sites (<em>ts> at the nest surface (where shimmering waves had been generated show higher flickering activity than the alternative non-trigger sites (<em>nts>. We measured the flickering activity of <em>ts>- and <em>nts>-surface bees from two experimental nests, before and after the colony had been aroused by a dummy wasp. Arousal increased rate and intensity of the flickering activity of both <em>ts>- and <em>nts> cohorts (P < 0.05, whereby the flickering intensity of <em>ts>-bees were higher than that of <em>nts>-bees (P < 0.05. Under arousal, the colonies also increased the number of flickering-active <em>ts>- and <em>nts>-cohorts (P < 0.05. This provides evidence that cohorts which are specialist at launching shimmering waves are found across the quiescent nest zone. It also proves that arousal may reinforce the responsiveness of quiescent curtain bees for participating in shimmering, practically by recruiting additional trigger site bees for expanding repetition of rate and intensity of shimmering waves. This finding confirms the <em>fs-transition> hypothesis and constitutes evidence that flickering is part of a basal colony-intrinsic information system
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Gladson Ricardo Flor Bertolini
2008-08-01
Full Text Available A dor e o edema são sinais, entre outros, que ocorrem durante a fase inflamatória no processo de cura de tendões lesados. A terapia antiinflamatória farmacológica recebe algumas críticas, com relação a seus efeitos deletérios para o reparo. Dessa forma, ganha corpo o uso de recursos físicos para o controle do processo. O objetivo do presente estudo foi avaliar o uso do laser de baixa potência sobre a dor e edema em tendão calcâneo de ratos submetidos a trauma experimental. Foram utilizados 28 ratos Wistar, divididos em quatro grupos: GC - submetido à lesão traumática e ao tratamento placebo; G2 - submetido à lesão e irradiado com laser 2J/cm²; G4 - submetido à lesão e irradiado com 4J/cm²; G8 - submetido à lesão e irradiado com 8J/cm². A lesão foi realizada com a queda de um peso sobre a face lateral do tendão calcâneo direito de cada animal, com energia de aproximadamente 0,40J. A dor foi avaliada pelo tempo de elevação da pata (TEP do animal caminhando durante um minuto, sobre um cilindro metálico com 30cm de diâmetro em 3rpm; a avaliação do edema ocorreu através de paquimetria; os momentos de avaliação foram: pré-lesão, pós-lesão, pós-tratamento, duas horas, oito horas, 24 horas e 5º dia de lesão. O tratamento com laser 670nm ocorreu de forma pontual e diária. Os resultados mostraram aumentos do TEP e formação de edema em todos os grupos após a lesão; para os grupos tratados houve redução da dor e do edema, fato observado no grupo controle apenas com relação à diminuição de edema no 5º dia de placebo. Conclui-se que o tratamento com laser de baixa potência diminuiu dor e edema nos animais com trauma tendíneo, de forma dose-dependente.During the injured tendons healing process there is the inflammatory phase, which occurs in the presence, among other signs, of pain and edema. The antiinflammatory drug therapy receives some criticism, with respect to its deleterious effects for the
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Complete BWR--EM LOCA analysis using the WRAP--EM system
International Nuclear Information System (INIS)
Beckmeyer, R.R.; Gregory, M.V.; Buckner, M.R.
1979-01-01
The Water Reactor Analysis Package, Evaluation Model (WRAP--EM), provides a complete analysis of postulated loss-of-coolant accidents (LOCA's) in light--water nuclear power reactors. The system is being developed at the Savannah River Laboratory (SRL) for use by the Nuclear Regulatory Commission (NRC) to interpret and evaluate reactor vendor, evaluation model (EM) analyses. The initial version of the WRAP--EM system for analysis of boiling water reactors (BWR's) is operational. To demonstrate the complete capability of the WRAP--BWR--EM system, a LOCA analysis has been performed for the Hope Creek Plant
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Lúcia de Noronha
2004-02-01
Full Text Available Este trabalho analisa o efeito da reparação cutânea do laser erbium:yttrium aluminunn garnet (YAG (Er:YAG em pele de ratos através de estudo histológico e morfométrico. Tatuaram-se duas figuras no dorso de cada animal (n = 35, denominadas controle e experimento. Na figura experimento, aplicaram-se três passadas de laser Er:YAG com parâmetros padronizados. Cinco animais foram eutanasiados nos dias 0, 7, 14, 28, 56, 84 e 112 de pós-operatório. O estudo histológico demonstrou no dia 0 dano de ablação médio de 215,24 micrômetros (mm, sendo homogêneo com vaporização da epiderme e porções superficiais da derme. O dano térmico residual foi pequeno (média de 41,45mm, observando-se áreas onde estava praticamente ausente. A fibroplasia cicatricial já estava presente no dia 7 (média de 55,58mm, aumentando rapidamente até o dia 28 (média de 209,49mm, quando atingiu um platô e se manteve até o dia 112. Não houve sinais de processo inflamatório agudo no dia 7 e a reepitelização já estava completa. Concluiu-se que a aplicação de laser na pele de ratos induz reparação cutânea ao longo de 112 dias nas condições do experimento.This study analyses the skin contracture effect of the erbium:YAG (Er:YAG laser on the skin of rats by light microscopic histological and morphometrical evaluations. Two squares of back skin were precision tattooed on each of the animals (n = 35, that were termed control and experimental skin. The experimental skin was treated with three passes of the Er:YAG laser with standardized parameters. Five animals were killed and skin specimens were analyzed at 00, 07, 14, 28, 56, 84 and 112 days. Histologic examination demonstrated a mean of 215.24 micrometers ablative damage that was homogeneous with complete vaporization of the epidermis and superficial dermis. The residual thermal damage was small (mean of 41.45 micrometers observing areas where it was absent. The cicatritial fibroplasy was present at
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Directory of Open Access Journals (Sweden)
Carlos M. Silva
2012-06-01
Full Text Available Eucalyptus bark contains significant amounts of triterpenoids with demonstrated bioactivity, namely triterpenic acids and their acetyl derivatives (ursolic, betulinic, oleanolic, betulonic, 3-acetylursolic, and 3-acetyloleanolic acids. In this work, the supercritical fluid extraction (SFE of <em>Eucalyptus> <em>globulus> deciduous bark was carried out with pure and modified carbon dioxide to recover this fraction, and the results were compared with those obtained by Soxhlet extraction with dichloromethane. The effects of pressure (100–200 bar, co-solvent (ethanol content (0, 5 and 8% wt, and multistep operation were studied in order to evaluate the applicability of SFE for their selective and efficient production. The individual extraction curves of the main families of compounds were measured, and the extracts analyzed by GC-MS. Results pointed out the influence of pressure and the important role played by the co-solvent. Ethanol can be used with advantage, since its effect is more important than increasing pressure by several tens of bar. At 160 bar and 40 °C, the introduction of 8% (wt of ethanol greatly improves the yield of triterpenoids more than threefold.
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Directory of Open Access Journals (Sweden)
Hsueh-Fen Juan
2012-08-01
Full Text Available <em>Helicobacter pyloriem> (<em>H. pyloriem>, the human stomach pathogen, lives on the inner surface of the stomach and causes chronic gastritis, peptic ulcer, and gastric cancer. Plasma membrane repair response is a matter of life and death for human cells against physical and biological damage. We here test the hypothesis that <em>H. pyloriem> also causes plasma membrane disruption injury, and that not only a membrane repair response but also a cell proliferation response are thereby activated. Vacuolating cytotoxin A (VacA and cytotoxin-associated gene A (CagA have been considered to be major <em>H. pyloriem> virulence factors. Gastric cancer cells were infected with <em>H. pyloriem> wild type (vacA+/cagA+, single mutant (ΔvacA or ΔcagA or double mutant (ΔvacA/ΔcagA strains and plasma membrane disruption events and consequent activation of membrane repair components monitored. <em>H. pyloriem> disrupts the host cell plasma membrane, allowing localized dye and extracellular Ca2+ influx. Ca2+-triggered members of the annexin family, A1 and A4, translocate, in response to injury, to the plasma membrane, and cell surface expression of an exocytotic maker of repair, LAMP-2, increases. Additional forms of plasma membrane disruption, unrelated to <em>H.
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NATURE AND LAW IN THE <em>INSTITUTAS> OF GAIO NATUREZA E DIREITO NAS <em>INSTITUTAS> DE GAIO
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Alfredo Carlos Storck
2011-09-01
Full Text Available
In a very famous passage of his <em>Institutes>, the ancient jurist Gaius had divided the Roman Private Law in two parts: the Civil Law and the Law of People. The former is the Law created by the Roman people, whereas the latter is the Law followed by every nation.
Despite its classical origin, there is some disagreement among specialists about the right way to interpret this distinction. By the beginning of the 20th century, historians like Michel Villey had seen in this distinction the influence of Greek philosophy (Stoic but even Aristotelian among the Roman jurists. But Levy and more recently Kelly have challenged this view and proposed that, in the roman period, philosophers and jurists had completely distinct notions of nature and natural law. The aim of this paper is not to prove the exact influence of Greek philosophy among jurists, but only to suggest that it is not possible to give an interpretation of the classical texts without ascribing to them a theoretical notion of the natural law.Em uma famosa passagem de suas <em>Institutas>, o jurista romano Gaio dividiu o direito privado em duas partes: o direito civil e o direito dos povos. O primeiro é o direito criado pelo povo romano enquanto o segundo é o direito seguido por todas as nações. A despeito de sua origem clássica, os especialistas discordam acerca do modo de interpretar essa tese. No início do século XX, historiadores como Michel Villey viram na distinção sinais da influência da filosofia grega (estóica e mesmo aristotélica entre os juristas romanos. Posteriormente Levy e mais recentemente Kelly contestaram essa afirmação e defenderam que filósofos e juristas possuíam, no período clássico, noções de natureza e direito natural completamente distintas. O objetivo desse artigo não está em provar a exata influência da filosofia grega entre os juristas, mas apenas em sugerir que não é possível fornecer uma interpretação dos
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Laser system using ultra-short laser pulses
Dantus, Marcos [Okemos, MI; Lozovoy, Vadim V [Okemos, MI; Comstock, Matthew [Milford, MI
2009-10-27
A laser system using ultrashort laser pulses is provided. In another aspect of the present invention, the system includes a laser, pulse shaper and detection device. A further aspect of the present invention employs a femtosecond laser and binary pulse shaping (BPS). Still another aspect of the present invention uses a laser beam pulse, a pulse shaper and a SHG crystal.
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Application of Various Lasers to Laser Trimming Resistance System
Institute of Scientific and Technical Information of China (English)
SUN Ji-feng
2007-01-01
Though the laser trimming resistance has been an old laser machining industry for over 30 years, the development of technology brings new alternative lasers which can be used for the traditional machining. The paper describes application of various lasers to laser trimming resistance system including early traditional krypton arc lamp pumped Nd:YAG to laser, modern popular diode pumped solid state laser and the present advanced harmonic diode pumped solid state laser. Using the new alternative lasers in the laser trimming resistance system can dramatically improve the yields and equipment performance.
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Directory of Open Access Journals (Sweden)
Alessandro Balestrieri
2006-03-01
Full Text Available Abstract To appreciate the influence of the introduction of the Eastern cottontail (<em>Sylvilagus floridanusem> on the food habits of the red fox (Vulpes vulpes, between June 1998 and February 2000 fox diet was investigated by means of scat analysis (N=115 in a 250 ha wide Natural Reserve of NW Italy, and compared with data collected in the same area prior to cottontail colonization (1988-1989. Comparison included also the diet of badgers (<em>Meles melesem>, considered as potential competitors for food resources. Alien lagomorphs (mean percent volume, Vm% = 68% represented by far the most exploited resource, only three other food items reaching values of mean percent volume barely higher than 5%. Cottontails frequency of occurrence did not vary according either to season or to their reproductive cycle (II-IX vs. X-I, whilst diet niche breadth varied inversely proportional to the use of this key-resource. Overall fox trophic niche breadth varied from 0.64 in 1988-89 to 0.31 in 1998-00 (B, Levin’s index. These findings led us to consider the feeding habits of the fox in the study area as a result of local specialization of a typical generalist carnivore, according to the predictions of optimal foraging theory. No variation occurred in the badger niche breadth since cottontail introduction, whilst niche overlap between foxes and badgers decreased from 0.59 to 0.13 (O, Pianka’s index, possibly reducing competition for food in summer. Riassunto Specializzazione alimentare a livello locale della Volpe <em>Vulpes vulpesem> in risposta all’introduzione del Silvilago <em>Sylvilagus floridanusem> (Italia nord occidentale. Per valutare gli effetti dell’introduzione del Silvilago (<em>Sylvilagus floridanusem> sul comportamento alimentare della volpe (<em>Vulpes vulpesem>, nel periodo giugno 1998-febbraio 2000, la dieta del carnivoro è stata definita tramite l’analisi di 115
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TOPOGRAFIA DE TÚNEIS COM LASER SCANNER TERRESTRE: ESTUDO DE CASO
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Jorge Pimentel Cintra
Full Text Available Apresenta-se a aplicação da tecnologia Laser Scanner 3D terrestre ao levantamento do túnel de adutora, escavado em rocha. Depois de apresentar o local, é descrito o problema, que consiste no levantamento preciso do túnel para identificar e coletar dados para quantificar alterações na sua secção transversal com relação à secção prevista em projeto, para a posterior correção desses defeitos. São resumidos os principais métodos possíveis de levantamento, listando prós e contras de cada um. A seguir mostram-se os fundamentos dessa tecnologia de levantamento bem como a metodologia dos trabalhos de campo e de escritório, incluindo o cálculo das coordenadas dos pontos do túnel. Finaliza-se com o controle de qualidade e uma avaliação do método, indicando seus pontos fortes comparado com outras metodologias.
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Metabolic Profiling of <em>Lactococcus lactisem> Under Different Culture Conditions
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Normah Mohd Noor
2012-07-01
Full Text Available Gas chromatography mass spectrometry (GC-MS and headspace gas chromatography mass spectrometry (HS/GC-MS were used to study metabolites produced by <em>Lactococcus lactisem> subsp. <em>cremoris> MG1363 grown at a temperature of 30 °C with and without agitation at 150 rpm, and at 37 °C without agitation. It was observed that <em>L. lactisem> produced more organic acids under agitation. Primary alcohols, aldehydes, ketones and polyols were identified as the corresponding trimethylsilyl (TMS derivatives, whereas amino acids and organic acids, including fatty acids, were detected through methyl chloroformate derivatization. HS analysis indicated that branched-chain methyl aldehydes, including 2-methylbutanal, 3-methylbutanal, and 2-methylpropanal are degdradation products of isoleucine, leucine or valine. Multivariate analysis (MVA using partial least squares discriminant analysis (PLS-DA revealed the major differences between treatments were due to changes of amino acids and fermentation products.
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Matérias estranhas em canela em pó e páprica em pó, comercializadas no estado de São Paulo
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CORREIA Marlene
2000-01-01
Full Text Available Com objetivos de padronizar metodologias para matérias estranhas em canela em pó e páprica em pó e de avaliar as condições higiênicas desses condimentos, foram adquiridas, no período de agosto a novembro de 1998, 78 amostras de canela em pó e 56 de páprica em pó, em estabelecimentos comerciais de seis cidades do Estado de São Paulo. Foram utilizados métodos da Association of Official Analytical Chemists International (AOAC - 1995, 16.14.12/968.38b para canela em pó e 16.14.22/977.25B para páprica em pó. Os métodos mostraram-se adequados, sem resíduos interferentes no papel de filtro que dificultasse o diagnóstico da análise e viáveis de serem utilizados nos laboratórios de Microscopia de Alimentos. Os resultados obtidos indicaram 100% das amostras contendo fragmentos de insetos; pêlos de roedor foram isolados em 73,1% de amostras de canela em pó e 34,0% de páprica em pó, enquanto ácaros mortos apareceram, respectivamente, em 37,2% e 12,5% de amostras. É necessário revisão da legislação de alimentos em vigor, com o estabelecimento de níveis de tolerância para fragmentos de insetos.
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Laser optically pumped by laser-produced plasma
International Nuclear Information System (INIS)
Silfvast, W.T.; Wood, O.R. II.
1975-01-01
Laser solids, liquids and gases are pumped by a new technique in which the output from an efficient molecular laser, such as a CO 2 laser, ionizes a medium, such as xenon, into a generally cylindrical plasma volume, in proximity to the pumped laser body. Breakdown yields a visible and ultraviolet-radiation-emitting plasma in that volume to pump the laser body. The spectral radiance of the plasma is significantly higher than that produced by a dc-discharge-heated plasma at nearly all wavelengths in the plasma spectrum. The risetime of radiation from the laser-produced plasma can also be significantly shorter than that of a dc heated plasma. A further advantage resides in the fact that in some applications the attenuating walls needed by flashlamps may be eliminated with the result that laser threshold is more readily reached. Traveling wave excitation may be provided by oblique incidence of the pumping laser beam through the ionizable medium to create sequential ionization of portions of that medium along the length of the pumped laser body. (auth)
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Diode laser-pumped Ho:YLF laser
International Nuclear Information System (INIS)
Hemmati, H.
1987-01-01
The author reports laser action in Ho:YLF at 2.06 μm following optical pumping with a cw diode laser array. Diode laser-pumped Nd-YAG and Ho:YAG have been reported recently. Lasers with a wavelength of 2 μm have medical and optical communication applications. The diode laser light is focused with a 60-mm focal length lens onto the YLF crystal. A high-reflectivity mirror with 100-mm radius of curvature was used as the output coupler. The lasing threshold was at 5 mWof incident power. This is higher than expected considering that a high reflector was used as the output coupler. However, a more uniform cooling of the crystal is expected to lower the lasing threshold. With 100 mW of pump power coupled into the crystal, --20 mW of 2-μm radiation was observed from this unoptimized setup. The 2-μm laser output is highly sensitive to output coupler alignment, YLF crystal temperature, and pump laser wavelength. The 20% optical conversion efficiency achieved in his preliminary measurements is expected to be improved by better crystal cooling, proper matching of laser wavelength to crystal absorption, variations in the concentration of Ho and sensitizers and use of a proper output coupler. A study of the parameters mentioned above and the effect of crystal temperature on the laser output is under way
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Lasers for the SILVA laser isotope separation process
International Nuclear Information System (INIS)
Lapierre, Y.
1997-01-01
The main principles of the laser isotope separation process for the production of enriched uranium at lower cost, are reviewed and the corresponding optimal laser characteristics are described. The development of the SILVA laser isotope separation process involved researches in the various domains of pump lasers, dye lasers, laser and optics systems and two test facilities for the feasibility studies which are expected for 1997
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Development of frequency tunable Ti:sapphire laser and dye laser pumped by a pulsed Nd:YAG laser
International Nuclear Information System (INIS)
Yi, Jong Hoon; Horn, Roland; Wendt, K.
2001-01-01
We investigated lasing characteristics of two kinds of tunable laser, liquid dye laser and solid Ti:sapphire crystal laser, pumped by high pulse repetition rate Nd:YAG laser. Dye laser showed drastically reduced pulsewidth compared with that of pump laser and it also contained large amount of amplified spontaneous emission. Ti:sapphire laser showed also reduced pulsewidth. But, the laser conversion pump laser and Ti:sapphire laser pulse, we used a Brewster-cut Pockel's cell for Q-switching. The laser was frequency doubled by a type I BBO crystal outside of the cavity.
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Energy Technology Data Exchange (ETDEWEB)
Bertella, Claudio
2001-07-01
The purpose of this study was to evaluate (in vivo) the effects of low-intensity Arsenide Gallium Aluminium laser application post-cavity preparation class 1. Six patients with bilateral pre-molars and molars indicated to extraction for orthodontics aim were selected. Four samples of these teeth underwent cavity preparation with deep from medium to high and two samples underwent cavity preparation from high to pulp expositions. The samples were constituted of two teeth of the same patient and received different treatments. One of the teeth underwent laser exposition and the other one was maintained as control, before restorative procedure with polycarboxylate cement. A diode laser ({lambda}=650 nm), output power 30 mW and fluencies of 1,8 J/cm{sup 2} and 2,7 J/cm{sup 2} in pre-molars and molars, respectively, was used for irradiation with repetition rate of 18 Hz in interrupted continuous wave mode. After seven days, the teeth were extracted and processed histologically with HE to verify morphological changes in the pulpy tissue. The four samples, which cavity preparation and restorative material were not in contact with the pulp, did not show histological differences between irradiated and non-irradiated teeth. Both of them presented the same characteristics of normality. The two samples with exposed pulpy tissue showed different results. The irradiated teeth presented no or slight inflammatory signs when compared to the control samples, which showed abscess in the coronary pulp interior and intense inflammatory infiltrated. These results suggest that the laser irradiation can be used as a therapeutic modality in clinical trials, in the conditions employed in this study. (author)
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Directory of Open Access Journals (Sweden)
Martínez Erika P.
2009-08-01
Full Text Available
In Colombia, citrus, tree tomato and mango crops are likely to suffer considerable losses from anthracnose caused by several <em>Colletotrichum> species, which were identified by the present study on infected organs of the three fruit crops, sampled in different regions of the country. Identification was based on their morphological and molecular characteristics, as well as on fungicide (benomyl and copper hydroxide sensitivity and pathogenicity tests. The latter assessed infectivity on both the original hosting crop and the other two crops (crossed infection, by putting the fungi in contact with organs taken from the three fruit crops. Molecular identification of the <em>Colletotrichum> species was carried out through amplification of rDNA ITS regions by means of <em>C. gloeosporioidesem> (CgInt and <em>C. acutatumem> (CaInt2 specific primer PCR combining the use of ITS4 universal primer. The results indicate that <em>C. acutatumem> is the infectious agent in Tahiti lime and tree tomato, and so is <em>C. gloeosporioidesem> in mango. Although <em>C. acutatumem> is the infectious agent in two diferent fruit species, the strains proved to be specific of their original hosts.
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Saghafi, S.; Penjweini, R.; Becker, K.; Kratky, K. W.; Dodt, H.-U.
2010-09-01
When moulds are illuminated by visible electromagnetic-EM radiations, several effects on nucleus materials and nucleotides can be detected. These effects have a significant influence on mould generation or destruction. This paper presents the effects and implications of a red diode laser beam (660 nm), a second-harmonics of a Nd:YAG laser emitting green beam (532 nm), or the combination of both, on the eradication of Pistachio mould fungus. Incident doses (ID) of both beams are kept identical throughout the experiment. The absorption spectrums of irradiated mouldy samples and the bright-greenish-yellow-fluorescence (BGYF) of fungus occurring in mould texture due to electronic excitation are investigated. We found that a combination of a green and a red laser beam with an ID of 0.5 J/cm2 provides the optimal effects on Pistachio mould fungus eradication.
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Directory of Open Access Journals (Sweden)
Fabiano Inácio de Souza
2013-04-01
Full Text Available OBJETIVOS: Avaliar os efeitos de monossialogangliosídeos (GM1 administrados com laser por via transdérmica na recuperação da lesão da medula espinal de ratos. MÉTODOS: Quarenta ratos Wistar machos foram submetidos a contusão da medula espinal usando NYU Impactor. No Grupo 1, os ratos receberam 0,2 ml de solução salina diária por via intraperitoneal; no Grupo 2, GM1 foi administrada intraperitonealmente em concentração de 30 mg/kg por dia; no Grupo 3, os ratos foram tratados diariamente com o laser a baixa temperatura sobre a pele, e no Grupo 4, a sessão de laser diária também continha GM1. Todos os grupos foram tratados durante 42 dias. Os animais foram avaliados pela escala funcional de Basso, Baettie e Bresnahan (BBB nos dias 7, 14, 21, 28, 35 e 42 após a lesão, e por histopatologia e potencial motor evocado 42 dias depois da lesão. RESULTADOS: Os animais do Grupo 4 apresentaram escores BBB mais elevados em comparação com os outros grupos. Não houve diferenças entre os grupos ou nas comparações ao longo do tempo. A avaliação histológica não mostrou diferenças, e tampouco foram encontradas diferenças significativas no potencial evocado. CONCLUSÃO: A GM1 associada ao uso de laser a baixa temperatura não mostra resultados superiores no tratamento de lesões da medula espinal de ratos. Nível de Evidência I, Experimental, Estudo Controlado de Animais.OBJECTIVES: to evaluate the effects of monosialoganglioside (gm1 administered transdermally with laser in the recovery of spinal cord injury in rats. METHODS: forty male wistar rats underwent spinal cord contusion using the nyu impactor. in group 1, the rats received 0,2 ml of saline intraperitoneally daily; in group 2, gm1 was administered intraperitoneally at a concentration of 30 mg/kg per day; in group 3, rats were treated daily with laser at low temperature on the skin, and in group 4, the daily laser session also contained gm1. all the groups were treated for 42
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Isolamento de micobactérias em Felis concolor em cativeiro
Directory of Open Access Journals (Sweden)
María Julia Traversa
2009-02-01
Full Text Available Este trabalho foi realizado em uma reserva natural da Argentina com antecedentes de tuberculose em uma suçuarana adulta. O objetivo foi identificar por meio de técnicas bacteriológicas e de biologia molecular as espécies isoladas da orofaringe de cinco suçuaranas que apresentavam sinais clínicos inespecíficos. As amostras foram colhidas das suçuaranas após sedação. Posteriormente foram processadas para obtenção do isolamento e identificação por meio de provas bioquímicas do gênero Mycobacterium pela técnica de PCR. Investigou-se a presença das seqüências de inserção IS6110 e IS1081 e hsp65. Obtiveram-se resultados positivos à coloração de Ziehl-Neelsen de quatro amostras, isolando cinco cepas de crescimento lento. As cepas foram classificadas como M. gordonae em dois casos e M. simiae, M scrofulaceum e M. avium/intracellulare em um. Por PRA, identificou-se o padrão de M. gordonae em três cepas e M. avium III ou M. simiae em dois.
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Leães, Sabrina Durgante
2008-01-01
Dissertação de mestrado em Design e Marketing O actual estado do Marketing em Moda é uma das questões ainda complexa com que se debate a sociedade global. As questões do Marketing em Moda percorrem alguns aspectos fundamentais tais como as constantes mutações do meio envolvente, a forma de como é percebida e comunicada a identidade das marcas de moda, em busca da melhor forma de segmentar o mercado e definir o seu posicionamento, bem como a reacção ao produto de moda do consumidor final. ...
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Directory of Open Access Journals (Sweden)
Wen Gu
2012-04-01
Full Text Available A series of new <em>N>-acylhydrazone derivatives were synthesized in good yields through the reactions of dehydroabietic acid hydrazide with a variety of substituted arylaldehydes. The structures of the synthesized compounds were confirmed by IR, 1H- and 13C-NMR, ESI-MS, elemental analysis and single crystal X-ray diffraction. From the crystal structure of compound 4l, the C=N double bonds of these <em>N>-acylhydrazones showed (<em>E>-configuration, while the NMR data of compounds 4a–q indicated the existence of two rotamers for each compound in solution. The target compounds were evaluated for their antibacterial activities against four microbial strains. The result suggested that several compounds exhibited pronounced antibacterial activities. Particularly, compound 4p exhibited good antibacterial activity against <em>Staphylococcus aureusem> and <em>Bacillus subtilisem> comparable to positive control. The possible antibacterial metabolism and the strategy for further optimization of this compound were also discussed.
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Photonic bandgap fiber lasers and multicore fiber lasers for next generation high power lasers
DEFF Research Database (Denmark)
Shirakawa, A.; Chen, M.; Suzuki, Y.
2014-01-01
Photonic bandgap fiber lasers are realizing new laser spectra and nonlinearity mitigation that a conventional fiber laser cannot. Multicore fiber lasers are a promising tool for power scaling by coherent beam combination. © 2014 OSA....
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Laser power sources and laser technology for accelerators
International Nuclear Information System (INIS)
Lowenthal, D.
1986-01-01
The requirements on laser power sources for advanced accelerator concepts are formidable. These requirements are driven by the need to deliver 5 TeV particles at luminosities of 10/sup 33/ - 10/sup 34/ cm/sup -2/ sec/sup -1/. Given that optical power can be transferred efficiently to the particles these accelerator parameters translate into single pulse laser output energies of several kilojoules and rep rates of 1-10 kHz. The average laser output power is then 10-20 MW. Larger average powers will be needed if efficient transfer proves not to be possible. A laser plant of this magnitude underscores the importance of high wall plug efficiency and reasonable cost in $/Watt. The interface between the laser output pulse format and the accelerator structure is another area that drives the laser requirements. Laser accelerators break up into two general architectures depending on the strength of the laser coupling. For strong coupling mechanisms, the architecture requires many ''small'' lasers powering the accelerator in a staged arrangement. For the weak coupling mechanisms, the architecture must feature a single large laser system whose power must be transported along the entire accelerator length. Both of these arrangements have demanding optical constraints in terms of phase matching sequential stages, beam combining arrays of laser outputs and optimizing coupling of laser power in a single accelerating stage
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Directory of Open Access Journals (Sweden)
Anna Rita Di Cerbo
2003-10-01
Full Text Available <em>Vulpes vulpesem> (Linnaeus, 1758 is one of the most common carnivore in Italy and its spread includes almost the whole national territory. The species shows an high ecological plasticity and a variable diet composition connected in part to human sources. This high adaptability permits the red foxes to colonize different habitats like the suburbs of large cities as well as the small villages located in mountain areas. On the other hand, the tourism pressure seems to assume a great importance in the Alps, also in those areas where the foxes live. So, indirect interactions could take place between these animals and the humans. The role of <em>V. vulpesem> in the zoonoses has not to be understated since this carnivore could transmit parasitic diseases that are able to cause serious pathologies in humans. This study aims just to investigate on intestinal communities of helmiths of <em>V. vulpesem> in order to make progress in current knowledge on epidemiological situation in Italian Alps. During 1998-2003, we have examined 450 foxes from Trentino Alto Adige, Veneto, Lombardia and Valle d'Aosta. The specimens collected were found dead or have been hunted (according to national law n. 157/92 in localities situated between 170 and 2200 m a.s.l. The carcasses were carried to the provincial sections of Zooprofilattici Institutes, where the intestine was drawn by each sample and all the material was sent to the Faculty of Veterinary Medicine of Milan. Parasitological examination of the small intestines was performed by the analysis of the whole sediment and counting technique (SCT. Parasites were preserved in alcohol 70° before to be clarified or stained and identified by microscope (Zeiss Axioscop. Mean abundance, mean intensity and prevalence were calculated for each taxon of helminth. Dates of sampling were grouped within the four seasons. Statistic tests were performed with software package SPSS rel. 11.5 and spatial analysis with the
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Laser pumped lasers for isotope separation
International Nuclear Information System (INIS)
Fry, S.M.
1976-01-01
A study of the isotope separation laser requirements reveals that high pressure polyatomic molecular gas laser pumped lasers can attain the necessary characteristics including tunability, energy output, pulse width, and repetition rate. The results of a search, made for molecules meeting the appropriate requirements for one of several pump schemes utilizing a CO 2 laser and with output in the 12 μm or 16μm wavelength range, are presented. Several methods of pumping are reviewed and two novel pump schemes are presented. A laser pumped laser device design is given, and operation of this device and associated diagnostic equipment is confirmed by repeating experiments in OCS and NH 3 . The results of OCS laser experiments show that an improvement in pump rate and output per unit length is obtained with the device, using a wedged transverse pumping scheme. A new multi-line laser system in NH 3 pumped by a TEA CO 2 laser is reported. More than forty transitions spanning the wavelength range of 9.2 to 13.8 μm are observed and identified. A strong output at 12.08 μm is one of the closest lines yet found to the required laser isotope separation wavelength. Far infrared emission near 65 μm is observed and is responsible for populating levels which lase in pure ammonia near 12.3 μm. Buffer gas (e.g., N 2 or He) pressures of approximately 40--800 torr cause energy transfer by collision-induced rotationaltransitions from the pumped antisymmetric to the lasing symmetric levels in the nu 2 = 1 band of ammonia. Most of the observed lines are aP(J,K) transitions which originate from the nu 2 /sup s/ band. Measurements of the pressure dependence of the laser output shows that some lines lase at pressures greater than one atmosphere. Transient behavior of the 12.08 μm line is calculated from a simplified analytic model and these calculations are compared to the experimental results
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Enzymatic Properties and Mutational Studies of Chalcone Synthase from <em>Physcomitrella patensem>
Directory of Open Access Journals (Sweden)
Mahiran Basri
2012-08-01
Full Text Available <em>Pp>CHS is a member of the type III polyketide synthase family and catalyses the synthesis of the flavonoid precursor naringenin chalcone from <em>p>-coumaroyl-CoA. Recent research reports the production of pyrone derivatives using either hexanoyl-CoA or butyryl-CoA as starter molecule. The Cys-His-Asn catalytic triad found in other plant chalcone synthase predicted polypeptides is conserved in <em>Pp>CHS. Site directed mutagenesis involving these amino acids residing in the active-site cavity revealed that the cavity volume of the active-site plays a significant role in the selection of starter molecules as well as product formation. Substitutions of Cys 170 with Arg and Ser amino acids decreased the ability of the <em>Pp>CHS to utilize hexanoyl-CoA as a starter molecule, which directly effected the production of pyrone derivatives (products. These substitutions are believed to have a restricted number of elongations of the growing polypeptide chain due to the smaller cavity volume of the mutant’s active site.
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Directory of Open Access Journals (Sweden)
Tatiana Azevedo Arraes
2008-02-01
Full Text Available OBJETIVO: Avaliar se a opacificação de cápsula posterior (OCP influenciaria na análise da camada de fibras nervosas pela polarimetria "scanning laser" (GDx. MÉTODOS: Trinta e sete pacientes pseudofácicos não glaucomatosos foram submetidos a análise da camada de fibras nervosas pelo GDx antes e após a realização de capsulotomia com Nd:YAG laser. RESULTADOS: Em cinco olhos, o GDx não conseguiu imagens aceitáveis pelos parâmetros de aquisição do aparelho. Em todos os outros, não foi observada diferença significante entre os valores médios das variáveis antes e após a realização da capsulotomia posterior. CONCLUSÃO: A presença de OCP em graus moderados e/ou quando há imagens aceitáveis em pacientes pseudofácicos não influencia o resultado da análise das imagens das fibras do nervo óptico pelo GDx. Apenas intensos graus de OCP que impeçam a obtenção de imagem analisável pelo aparelho inviabilizam o exame.PURPOSE: To evaluate if posterior capsule opacification (PCO would alter the analysis of nerve fiber layer using the scanning laser polarimetry (GDx. METHODS: Pseudophakic non-glaucomatosous eyes (37 patients underwent nerve fiber layer analysis using GDx before and after posterior capsulotomy with Nd:YAG Laser. RESULTS: In five eyes, GDx did not obtain acceptable images using the device's parameters of acquisition. In the others, mean variable values did not reach significant difference before and after posterior capsulotomy. CONCLUSION: Moderate degrees of PCO and/or acceptable images in pseudophakic patients do not alter the analysis of nerve fiber layer by GDx. Only intense degrees of PCO that hinder analyzable images make the examination impracticable.
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Future prospects of laser diodes and fiber lasers
International Nuclear Information System (INIS)
Ueda, Ken-ichi
2000-01-01
For the next century we should develop new concepts for coherent control of light generation and propagation. Owing to the recent development of ultra fine structures in semiconductor lasers, fiber lasers, and various kinds of waveguide structure, we can make optical devices which control the light propagation artificially. But, the phase locking and phase control of multiple laser oscillators are one of the most important directions of laser science and technology. The coherent summation has been a dream of laser since 1960. Is it possible to solve this old and quite challenging problem for laser science? This is also a very basic concept because the laser action based on the stimulated emission is the process of coherent summation of huge number of photons emitted from individual atoms. In this paper, I discuss the fundamental direction of laser research in the next ten or twenty years. The active optics and laser technology should be combined intrinsically in near future. (author)
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Directory of Open Access Journals (Sweden)
Markus Hollaus
2012-10-01
Full Text Available This paper presents a methodology for the derivation of structural parameters and stem volume in forests based on Airborne Laser Scanning (ALS data. We describe three different measures of horizontal and vertical canopy structure: (1 tree crown segmentation, (2 compactness of vegetation patches, and (3 vertical layering of vegetation patches and canopy cover. An empirical regression model for the derivation of stem volume from the ALS and forest inventory sample plot data is described and its results are validated with extensive reference data. Different study areas in Austria were used to illustrate the workflows. The presented study demonstrates the applicability of the proposed methods on study sites and ALS data of differing characteristics, as well as it points out the suitability of ALS as a tool for reliable wide area assessment of structural parameters and stem volume for forested areas.ResumoEsse artigo apresenta uma metodologia para derivação de parâmetros estruturais e de volume de madeira em florestas baseado em dados de Laser Scanner Aerotransportado (ALS. Nós descrevemos três diferentes medidas da estrutura horizontal e vertical da copa: (1 segmentação da copa da árvore, (2 compacidade das manchas de vegetação, (3 estratificação vertical das manchas de vegetação e cobertura do dossel. Um modelo empírico de regressão para derivar o volume de madeira fazendo uso de dados ALS e dados amostrais obtidos em inventário florestal é descrito e seus resultados são validados com extensivos dados de referência. Diferentes áreas na Áustria foram utilizadas para ilustrar o fluxo de trabalho. O estudo apresentado demonstra a aplicabilidade dos métodos propostos nas áreas de estudo e dos dados ALS de diferentes características, bem como aponta a adequação do ALS como ferramenta confiável para avaliação de parâmetros de estrutura e de volume de madeira de amplas áreas florestais.
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International Nuclear Information System (INIS)
Richardson, Martin; Hammons, Dennis; Eichenholz, Jason; Chai, Bruce; Ye, Qing; Jang, Won; Shah, Lawrence
1999-01-01
We review new developments with a new laser host material, YCa 4 O(BO 3 ) 3 or YCOB. Lasers based on this host material will open new opportunities for the development of compact, high-power, frequency-agile visible and near IR laser sources, as well as sources for ultrashort pulses. Efficient diode-pumped laser action with both Nd-doped and Yb-doped YCOB has already been demonstrated. Moreover, since these materials are biaxial, and have high nonlinear optical coefficients, they have become the first laser materials available as efficient self-frequency-doubled lasers, capable of providing tunable laser emission in several regions of the visible spectrum. Self-frequency doubling eliminates the need for inclusion of a nonlinear optical element within or external to the laser resonator. These laser materials possess excellent thermal and optical properties, have high laser-damage thresholds, and can be grown to large sizes. In addition they are non-hygroscopic. They therefore possess all the characteristics necessary for laser materials required in rugged, compact systems. Here we summarize the rapid progress made in the development of this new class of lasers, and review their potential for a number of applications. (author)
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Artérias mesentéricas cranial e caudal da paca (Cuniculus paca, L. 1766
Directory of Open Access Journals (Sweden)
Isabela Cristina de Souza Marques
2012-10-01
Full Text Available http://dx.doi.org/10.5007/2175-7925.2013v26n1p165 A paca (Cuniculus paca, Linnaeus, 1766 é um roedor de porte médio, que embora pertença à fauna brasileira, poucas são as informações sobre sua morfologia na literatura especializada. Nesse sentido, objetivou-se descrever a origem e as ramificações de suas artérias mesentéricas cranial e caudal no intuito de contribuir com estudos de anatomia comparativa. Foram utilizados dez animais, entre machos e fêmeas, que após o óbito, tiveram sua parede torácica rebatida entre a quarta e a sexta costelas, para a exposição da aorta torácica, a qual foi canulada no sentido caudal e procedeu-se a injeção de solução de neoprene do tipo látex, corado convenientemente, para o preenchimento de todo o sistema arterial. Estas preparações foram fixadas em solução aquosa de formol a 10% por período superior à 72h; em seguida, as peças foram dissecadas e as artérias mesentéricas cranial e caudal identificadas. A artéria mesentérica cranial se originava da aorta abdominal, caudalmente à artéria celíaca, emitindo os seguintes ramos arteriais: pancreaticoduodenal caudal, pancreáticos, jejunais, íleocólicos e cecais. A origem da artéria mesentérica caudal ocorria próximo ao final da aorta abdominal, e este vaso emitia a artéria cólica esquerda e a artéria retal cranial, da qual partiam as artérias sigmóideas. Constatou-se que houve pouca variação no padrão de ramificação das artérias em relação aos referidos roedores e mamíferos domésticos.
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Meesters, Arne A; Nieboer, Marilin J; Kezic, Sanja; de Rie, Menno A; Wolkerstorfer, Albert
2018-05-07
Efficacy of topical anesthetics can be enhanced by pretreatment of the skin with ablative fractional lasers. However, little is known about the role of parameters such as laser modality and laser density settings in this technique. Aims of this study were to compare the efficacy of pretreatment with two different ablative fractional laser modalities, a CO 2 laser and an Er:YAG laser, and to assess the role of laser density in ablative fractional laser assisted topical anesthesia. In each of 15 healthy subjects, four 10 × 10 mm test regions on the back were randomized to pretreatment (70-75 μm ablation depth) with CO 2 laser at 5% density, CO 2 laser at 15% density, Er:YAG laser at 5% density or Er:YAG laser at 15% density. Articaine hydrochloride 40 mg/ml + epinephrine 10 μg/ml solution was applied under occlusion to all four test regions. After 15 minutes, a pass with the CO 2 laser (1,500 μm ablation depth) was administered as pain stimulus to each test region. A reference pain stimulus was given on unanesthetized skin. The main outcome parameter, pain, was scored on a 0-10 visual analogue scale (VAS) after each pain stimulus. Median VAS scores were 1.50 [CO 2 5%], 0.50 [CO 2 15%], 1.50 [Er:YAG 5%], 0.43 [Er:YAG 15%], and 4.50 [unanesthetized reference]. VAS scores for all pretreated test regions were significantly lower compared to the untreated reference region (P laser pretreated regions. However, VAS scores were significantly lower at 15% density compared to 5% density for both for the CO 2 laser (P laser (P laser was considered slightly more painful than pretreatment with Er:YAG laser by the subjects. Fractional laser assisted topical anesthesia is effective even with very low energy settings and an occlusion time of only 15 minutes. Both the CO 2 laser and the Er:YAG laser can be used to assist topical anesthesia although the CO 2 laser pretreatment is experienced as more painful. In our study settings, using articaine
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Laser beam cutting method. Laser ko ni yoru kaitai koho
Energy Technology Data Exchange (ETDEWEB)
Kutsumizu, A. (Obayashi Corp., Osaka (Japan))
1991-07-01
In this special issue paper concerning the demolition of concrete structures, was introduced a demolition of concrete structures using laser, of which practical application is expected due to the remarkable progress of generating power and efficiency of laser radiator. The characteristics of laser beam which can give a temperature of one million centigrade at the irradiated spot, the laser radiator consisting of laser medium, laser resonator and pumping apparatus, and the laser kinds for working, such as CO{sub 2} laser, YAG laser and CO laser, were described. The basic constitution of laser cutting equipment consisting of large generating power radiator, beam transmitter, beam condenser, and nozzle for working was also illustrated. Furthermore, strong and weak points in the laser cutting for concrete and reinforcement were enumerated. Applications of laser to cutting of reinforced and unreinforced concrete constructions were shown, and the concept and safety measure for application of laser to practical demolition was discussed. 5 refs., 8 figs.
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Efetividade da fluorescência a laser no diagnóstico de lesões de cárie. Estudos in vitro e in vivo
Diniz, Michele Baffi [UNESP
2006-01-01
O objetivo do presente estudo foi avaliar a efetividade da fluorescência a laser (KaVo DIAGNOdent) para a determinação da severidade de lesões de cárie oclusal em dentes permanentes in vivo e para determinação da remineralização in vitro de lesões de cárie induzidas artificialmente em esmalte de dentes bovinos. No estudo in vitro, 78 blocos de esmalte com lesões de cárie artificial (mancha branca) com valores de dureza Vickers de 38,48 l 0,85 foram submetidos ao tratamento com dentifrício flu...
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Directory of Open Access Journals (Sweden)
Poliani de Oliveira
2012-02-01
Full Text Available OBJETIVO: Verificar os efeitos da associação do Biosilicato® com o US e com o LLLT no processo de consolidação óssea em ratos, a partir da análise biomecânica e histológica. MÉTODOS: Foram utilizados 40 ratos machos distribuídos em quatro grupos (n = 10: grupo controle fratura sem tratamento (GCF; grupo tratado com Biosilicato® (GB; grupo tratado com Biosilicato® + laser (GBL; grupo tratado com Biosilicato® + US (GBUS. RESULTADOS: A análise biomecânica não apresentou diferença estatisticamente significativa nos grupos após o período experimental de 14 dias. Na análise morfométrica, o grupo controle apresentou presença moderada de tecido ósseo neoformado no interior dos defeitos e o grupo tratado com Biosilicato® apresentou resultados semelhantes. No entanto, foi observado o potencial osteogênico do biomaterial, uma vez que houve grande presença de células e tecido ósseo ao redor das partículas. Interessantemente, os grupos Biosilicato® associado ao laser terapêutico e ao US demonstraram quantidades menores de deposição de tecido ósseo quando comparados aos grupos controle fratura e Biosilicato®. CONCLUSÃO: A partir dos dados deste estudo podemos concluir que o Biosilicato® foi capaz de acelerar e potencializar a recuperação óssea, através da modulação do processo inflamatório e da estimulação da formação de tecido ósseo novo. No entanto, quando a LLLT ou o US foram associados, não foram encontrados resultados positivos.OBJECTIVE: Verify the effects of the association between Biosilicate® and ultrasound and, Biosilicate® and laser in bone consolidation process of rats, through the biomechanical and histological analysis. METHODS: Forthy male rats were used. The animals were randomized into four groups (n=10: control group fracture no treated (CGF; group treated with Biosilicate® (BG; group treated with Biosilicate® and laser (BLG; group treated with Biosilicate® and ultrasound (BUG. RESULTS
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Ultrashort pulse laser technology laser sources and applications
Schrempel, Frank; Dausinger, Friedrich
2016-01-01
Ultrashort laser pulses with durations in the femtosecond range up to a few picoseconds provide a unique method for precise materials processing or medical applications. Paired with the recent developments in ultrashort pulse lasers, this technology is finding its way into various application fields. The book gives a comprehensive overview of the principles and applications of ultrashort pulse lasers, especially applied to medicine and production technology. Recent advances in laser technology are discussed in detail. This covers the development of reliable and cheap low power laser sources as well as high average power ultrashort pulse lasers for large scale manufacturing. The fundamentals of laser-matter-interaction as well as processing strategies and the required system technology are discussed for these laser sources with respect to precise materials processing. Finally, different applications within medicine, measurement technology or materials processing are highlighted.
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Directory of Open Access Journals (Sweden)
Rosalba Alonso-Rodriguez
2012-05-01
Full Text Available The dinoflagellate <em>Gymnodinium catenatumem> produces paralyzing shellfish poisons that are consumed and accumulated by bivalves. We performed short-term feeding experiments to examine ingestion, accumulation, biotransformation, histopathology, and paralysis in the juvenile Pacific calico scallop <em>Argopecten ventricosusem> that consume this dinoflagellate. Depletion of algal cells was measured in closed systems. Histopathological preparations were microscopically analyzed. Paralysis was observed and the time of recovery recorded. Accumulation and possible biotransformation of toxins were measured by HPLC analysis. Feeding activity in treated scallops showed that scallops produced pseudofeces, ingestion rates decreased at 8 h; approximately 60% of the scallops were paralyzed and melanin production and hemocyte aggregation were observed in several tissues at 15 h. HPLC analysis showed that the only toxins present in the dinoflagellates and scallops were the <em>N>-sulfo-carbamoyl toxins (C1, C2; after hydrolysis, the carbamate toxins (epimers GTX2/3 were present. C1 and C2 toxins were most common in the mantle, followed by the digestive gland and stomach-complex, adductor muscle, kidney and rectum group, and finally, gills. Toxin profiles in scallop tissue were similar to the dinoflagellate; biotransformations were not present in the scallops in this short-term feeding experiment.
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Directory of Open Access Journals (Sweden)
Maria Elisabetta Guerzoni
2012-06-01
Full Text Available Chemical constituents of liverwort (<em>Porella cordaeanaem> extracts have been identified using solid-phase microextraction-gas chromatography mass spectrometry (SPME-GC/MS. The methanol, ethanol and ethyl acetate extracts were rich in terpenoids such as sesquiterpene hydrocarbons (53.12%, 51.68%, 23.16%, and monoterpene hydrocarbons (22.83%, 18.90%, 23.36%, respectively. The dominant compounds in the extracts were β-phellandrene (15.54%, 13.66%, 12.10% and β-caryophyllene (10.72%, 8.29%, 7.79%, respectively. The antimicrobial activity of the extracts was evaluated against eleven food microorganisms using the microdilution and disc diffusion methods. The minimum inhibitory concentration (MIC varied from 0.50 to 2.00 mg/mL for yeast strains (<em>Saccharomyces cerevisiae 635em>, <em>Zygosacharomyces bailii 45em>, <em>Aerobasidium pullulans L6Fem>, <em>Pichia membranaefaciens OC 71em>, <em>Pichia membranaefaciens OC 70em>, <em>Pichia anomalaem> <em>CBS 5759em>, <em>Pichia anomala DBVPG 3003em> and<em> em>
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Energy Technology Data Exchange (ETDEWEB)
1993-07-01
It is the intent of EM International to describe the Office of Environmental Restoration and Waste Management`s (EM`s) various roles and responsibilities within the international community. Cooperative agreements and programs, descriptions of projects and technologies, and synopses of visits to international sites are all highlighted in this semiannual journal. Focus on EM programs in this issue is on international collaboration in vitrification projects. Technology highlights covers: in situ sealing for contaminated sites; and remote sensors for toxic pollutants. Section on profiles of countries includes: Arctic contamination by the former Soviet Union, and EM activities with Germany--cooperative arrangements.
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Laser beam diagnostics for kilowatt power pulsed YAG laser
International Nuclear Information System (INIS)
Liu, Yi; Leong, Keng H.
1992-01-01
There is a growing need for high power YAG laser beam diagnostics with the recent introduction of such lasers in laser material processing. In this paper, we will describe the use of a commercially available laser beam analyzer (Prometec) to profile the laser beam from a 1600 W pulsed Nd:YAG laser that has a 1 mm fiber optic beam delivery system. The selection of laser pulse frequency and pulse width for the measurement is discussed. Laser beam propagation parameters by various optical components such as fibers and lenses can be determined from measurements using this device. The importance of such measurements will be discussed
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Laser materials processing with diode lasers
Li, Lin; Lawrence, Jonathan; Spencer, Julian T.
1996-01-01
Laser materials processing is currently dominated by CO2, Nd-YAG and Excimer lasers. Continuous advances in semiconductor laser technology over the last decade have increased the average power output of the devices annualy by two fold, resulting in the commercial availability of the diode lasers today with delivery output powers in excess of 60W in CW mode and 5kW in qasi-CW mode. The advantages of compactness, high reliability, high efficiency and potential low cost, due to the mass producti...
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Transurethral vaporesection of prostate: diode laser or thulium laser?
Tan, Xinji; Zhang, Xiaobo; Li, Dongjie; Chen, Xiong; Dai, Yuanqing; Gu, Jie; Chen, Mingquan; Hu, Sheng; Bai, Yao; Ning, Yu
2018-05-01
This study compared the safety and effectiveness of the diode laser and thulium laser during prostate transurethral vaporesection for treating benign prostate hyperplasia (BPH). We retrospectively analyzed 205 patients with BPH who underwent a diode laser or thulium laser technique for prostate transurethral vaporesection from June 2016 to June 2017 and who were followed up for 3 months. Baseline characteristics of the patients, perioperative data, postoperative outcomes, and complications were compared. We also assessed the International Prostate Symptom Score (IPSS), quality of life (QoL), maximum flow rate (Q max ), average flow rate (AFR), and postvoid residual volume (PVR) at 1 and 3 months postoperatively to evaluate the functional improvement of each group. There were no significant differences between the diode laser and thulium laser groups related to age, prostate volume, operative time, postoperative hospital stays, hospitalization costs, or perioperative data. The catheterization time was 3.5 ± 0.8 days for the diode laser group and 4.7 ± 1.8 days for the thulium laser group (p diode laser and thulium laser contributes to safe, effective transurethral vaporesection in patients with symptomatic BPH. Diode laser, however, is better than thulium laser for prostate transurethral vaporesection because of its shorter catheterization time. The choice of surgical approach is more important than the choice of laser types during clinical decision making for transurethral laser prostatectomy.
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Directory of Open Access Journals (Sweden)
Cíntia Helena Santuzzi
2011-04-01
Full Text Available FUNDAMENTOS: A laserterapia de baixa potência e os inibidores seletivos da ciclooxigenase-2 (ICOX2 vem sendo muito utilizados para modular a resposta inflamatória, entretanto, os seus efeitos na reepitelização de feridas não são bem compreendidos. OBJETIVO: Avaliar os efeitos isolados e combinados da laserterapia de baixa potência e da ICOX2 na reepitelização de ferida incisional na pele de camundongos. MÉTODO: Foi induzida uma ferida de 1 cm no dorso de cada camundongo, que foram divididos em quatro grupos (N=20: Controle, Laserterapia, Tratados com celecoxib e Terapia conjugada. Os animais dos grupos celecoxib e Terapia conjugada foram tratados com celecoxib por 10 dias antes da incisão cutânea. As feridas experimentais foram irradiadas com laserterapia de baixa potência He-Ne (632nm, dose: 4J/cm2 em varredura, por 12 segundos durante três dias consecutivos nos grupos Laserterapia e Terapia conjugada. Os animais foram sacrificados no 3º dia de pós-operatório. Amostras das feridas foram coletadas e coradas (Tricromio de Masson para análise histomorfométrica. RESULTADOS: Tanto o grupo Laserterapia, quanto o grupo celecoxib, mostrou aumento da reepitelização cutânea em relação ao grupo Controle, entretanto, o grupo Terapia conjugada não apresentou diferenças. Quanto à queratinização o grupo Laserterapia e Terapia conjugada apresentaram redução dos queratinócitos, comparados com o grupo Controle. CONCLUSÕES: Os resultados mostram que o uso da laserterapia de baixa potência e da ICOX2 isoladamente aumentam as células epiteliais, mas somente a laserterapia de baixa potência reduziu os queratinócitos cutâneos. O tratamento conjugado restabelece a reepitelização inata e dimunui a queratinização, embora ocorra uma acelerada contração da ferida com melhora na organização da ferida na pele de camundongos.BACKGROUND: Low level laser therapy and cyclooxygenase-2 (ICOX2 selective inhibitors have been widely used
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Home range dynamics of mountain hare (<em>Lepus timidusem> in the Swiss Alps
Directory of Open Access Journals (Sweden)
Anne-Sophie Genini-Gamboni
2009-02-01
Full Text Available Abstract Little is known on the ecology and behaviour of alpine mountain hare (<em>Lepus timidusem>. Between 1996 and 1997 we analysed by radiotracking the pattern of space use of 8 mountain hares from the Swiss Alps. We estimated home range size using both the kernel density estimator and the minimum convex polygon. We found smaller ranges (38 ha compared to those reported for the species in boreal or arctic habitats, but similar to ranges in Scotland. Hares did not use a centre of major activity (core area and showed high home range overlap, confirming their non-territorial behaviour. Smaller ranges were used during winter compared to the other seasons, whilst no difference in size was found between sexes. Riassunto Dinamica dell'uso dello spazio della lepre bianca (<em>Lepus timidusem> nelle Alpi Svizzere Le informazioni relative all'ecologia e al comportamento della lepre alpina (<em>Lepus timidusem> sono ad oggi scarse. In questo studio abbiamo analizzato l'utilizzo dello spazio di una popolazione di lepre bianca sulle Alpi Svizzere. Tra il 1996 e il 1997 sono stati marcati con redio collare 8 individui di lepre alpina. L'<em>home rangeem> è stato calcolato utilizzando lo stimatore di densità kernel (KDE ed il metodo del minimo poligono convesso (MCP. L'ampiezza degli <em>home rangeem> (38 ha è risultata inferiore a quella riportata per la specie in habitat boreali ed artici. ma simile a quella riscontrata in Scozia. All'interno dell <em>home rangeem> non è stato rilevato alcun centro di maggiore attività (<em>core areaem> ed è stata evidenziata una notevole sovrapposizione tra gli stessi, confermando la non territorialità della specie. Le aree frequentate in inverno sono risultate più piccole rispetto alle altre stagioni e non sono state riscontrate differenze tra i sessi.
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Bismuth silicate glass: A new choice for 2 μm fiber lasers
Ding, Jia; Zhao, Guoying; Tian, Ying; Chen, Wei; Hu, Lili
2012-11-01
We report on a new Yb3+/Tm3+/Ho3+ co-doped bismuth silicate glass: SiO2-Bi2O3-R2O (R = Li, Na, K) for 2 μm fiber lasers. Bi2O3 was introduced into alkali silicate glass to optimize 2 μm emission properties. Physical, chemical and spectroscopic properties of Yb3+/Tm3+/Ho3+ co-doped SiO2-Bi2O3-R2O (SBR) glass were presented. The Yb3+/Tm3+/Ho3+ co-doped SBR glass shows excellent thermal stability (ΔT = 162 °C), an intense 2.0 μm emission pumped by 980 nm LD with a lifetime of 1.33 ms and width of 168 nm, large maximum emission cross section of Ho3+ (5.3 × 10-21 cm2), thus large σemτ product (7.049 × 10-24 cm2 s), which suggest its application in 2 μm fiber lasers.
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Directory of Open Access Journals (Sweden)
Christopher J. Tuohy
2012-08-01
Full Text Available <em>Botulinum Neurotoxinem> A (BoNT-A injections have been used for the treatment of muscle contractures and spasticity. This study assessed the influence of (BoNT-A injections on passive biomechanical properties of the muscle-tendon unit. Mouse gastrocnemius muscle (GC was injected with BoNT-A (<em>n> = 18 or normal saline (<em>n> = 18 and passive, non-destructive, <em>in vivoem> load relaxation experimentation was performed to examine how the muscle-tendon unit behaves after chemical denervation with BoNT-A. Injection of BoNT-A impaired passive muscle recovery (15% <em>vs.> 35% recovery to pre-stretching baseline, <em>p> < 0.05 and decreased GC stiffness (0.531 ± 0.061 N/mm <em>vs.> 0.780 ± 0.037 N/mm, <em>p> < 0.05 compared to saline controls. The successful use of BoNT-A injections as an adjunct to physical therapy may be in part attributed to the disruption of the stretch reflex; thereby modulating <em>in vivoem> passive muscle properties. However, it is also possible that BoNT-A injection may alter the structure of skeletal muscle; thus modulating the <em>in vivoem> passive biomechanical properties of the muscle-tendon unit.
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Directory of Open Access Journals (Sweden)
Anna Brangi
1995-12-01
Full Text Available Abstract Between 1989 and 1991, 284 scats of stone marten (<em>Martes foinaem> and 642 scats of red fox (<em>Vulpes vulpesem> were collected in a 280 km² mountainous area in the northern Apennines. The scats were analyzed to identify differences between the two species' diets. The prey were grouped in 6 food categories: Fruits, Other Vegetables, Small Mammals, Other Vertebrates, Invertebrates and Garbage. Annual trophic niche was wider in the Red fox (0.62 than in the stone marten (0.53. We also found a large overlap between the two species with some small differences: Other Vertebrates, Small Mammals and Other Vegetables were more used by the Red fox, while Fruits were more used by the stone marten. Riassunto Variazioni stagionali della sovrapposizione di nicchia trofica della faina (<em>Martes foinaem> e della volpe (<em>Vulpes vulpesem> in un'area montana degli Appennini settentrionali - Tra il 1989 e il 1991 sono state raccolte 284 feci di faina (<em>Martes foinaem> e 642 feci di volpe (<em>Vulpes vulpesem> in un'area montuosa di 280 km² situata nell'Appennino settentrionale. Le feci sono state analizzate per evidenziare le eventuali differenze nella dieta delle due specie. Le singole prede sono state raggruppate in 6 categorie alimentari: Frutta, Altri Vegetali, Micromammiferi, Altri Vertebrati, Invertebrati, Rifiuti. L'ampiezza annuale della dieta è risultata maggiore nella Volpe (0,62 che non nella Faina (0,53. È stata trovata inoltre una larga sovrapposizione tra le due specie con alcune differenze nell'uso degli Altri Vertebrati, dei Micromammiferi e degli Altri Vegetali che è maggiore nella Volpe e della Frutta, maggiore nella Faina.
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Directory of Open Access Journals (Sweden)
Bajonero Johanna
2008-12-01
Full Text Available
<em>Apanteles gelechiidivorisem> es un parasitoide de larvas de <em>Tuta absolutaem> (Lepidoptera: Gelechiidae, una plaga importante de cultivos como el tomate y la papa. El uso de este insecto para el control biológico no se ha implementado eficientemente debido a la falta de conocimiento de la biología, específicamente del ciclo de vida y el efecto de factores externos, como la temperatura, en su capacidad parasítica. Se evaluó el desarrollo y la capacidad reproductiva de <em>A. gelechiidivorisem> en cuatro condiciones térmicas: 14, 20, 26 y 32 °C. En la evaluación del desarrollo se realizó una descripción del ciclo, se determinó la duración total de este, se estimaron los umbrales térmicos para cada estadio utilizando el modelo de Lactin y se hallaron los grados día. En la evaluación de la capacidad reproductiva se variaron las densidades del hospedero ofrecidas a una pareja recién emergida de la avispa de 5 hasta 160 y se contó el número de adultos emergidos con los cuales se evaluó longevidad y fecundidad. Adicionalmente se ajustó un modelo de respuesta funcional. La duración del ciclo de vida para las temperaturas evaluadas fue de 39 días en 14 °C, 34 en 20 °C, 19 en 26 °C y 17 en 32 °C. La longevidad fue de 7,5 (14 °C, 7 (20 °C, 5 (26 °C y 2,4 (32 °C días. La temperatura a la cual se pueden optimizar los parámetros reproductivos de esta avispa se encuentra entre 20 y 26 °C.
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Feeding habits of the genet <em>Genetta genettaem> in an Iberian continental wetland
Directory of Open Access Journals (Sweden)
Maite Sánchez
2009-02-01
Full Text Available Abstract This study quantified the diet of the genet <em>Genetta genettaem> in an Iberian continental wetland, the Galachos Nature Reserve, northern Spain, based on the frequency with which items appeared in five monthly-surveyed latrines during 2004-2005. Prey types were identified <em>de visuem> using identification keys and expert advice. the genet was confirmed as an opportunistic and generalist predator, its diet including mammals (95.0%, plants (68.3% and arthropods (60.0% as main prey. With the exception of a newly available prey species, the alien crayfish <em>Procambarus clarkiiem>, the genet probably consumed arthropods because of chance encounters rather than active search. The consumption of fruits and small mammals varied seasonally. Riassunto Alimentazione della genetta <em>Genetta genettaem> in un'area umida continentale della penisola iberica La dieta della genetta è stata investigata in un'area umida interna della Spagna settentrionale, la riserva Naturale dei Galachos. La frequenza di ciascuna categoria alimentare è stata espressa come numero di occorrenze mansili in cinque latrine monitorate per il periodo 2004-2005. Le categorie sono state identificate <em>de visuem> tramite chiavi per il riconoscimento o l'intervento di singoli esperti. I risultati confermano il comportamento alimentare generalista e opportunista della genetta. La dieta ha incluso principalmente mammiferi (95%, vegetali (68.3% e artropodi (60%. Questi ultimi, con l'eccezione del gambero <em>Procambarus clarkiiem>, introdotto e di recente presenza, sono probabilmente utilizzati in modo opportunistico, piuttosto che in seguito a ricerca attiva. L'uso dei frutti e dei micromammiferi varia stagionalmente.
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Directory of Open Access Journals (Sweden)
FA Reis
2008-06-01
Full Text Available CONTEXTUALIZAÇÃO: As lesões nervosas periféricas podem comprometer atividades diárias de um indivíduo e resultam em perda da sensibilidade e motricidade do território inervado. OBJETIVO: Com o intuito de acelerar os processos regenerativos, objetivou-se analisar a influência da aplicação do laser de arsenieto de gálio e alumínio (AsGaAl, 660Nm sobre a recuperação funcional do nervo ciático de ratos. MATERIAIS E MÉTODOS: O nervo ciático de 12 ratos Wistar foi submetido à lesão por neurotmese e anastomose epineural e divididos em dois grupos: controle e laserterapia. Após a lesão, utilizou-se o laser de GaAlAs, 660Nm, 4J/cm², 26,3mW, feixe de 0,63cm², em três pontos eqüidistantes sobre a lesão, por 20 dias. As impressões das pegadas dos animais foram obtidas antes e após (sete, 14 e 21 dias pós-operatórios o procedimento cirúrgico e calculou-se o índice funcional do ciático (IFC. RESULTADOS: A comparação do IFC não resultou em diferença significante (p>0,05 entre os grupos. CONCLUSÕES: Conclui-se que os parâmetros e métodos empregados na laserterapia demonstram resultados nulos sobre o IFC no período avaliado.CONTEXT: Peripheral nerve injuries result in sensory and motor losses in the innervated area and can hinder individuals’ daily activities. Objective: The objective was to analyze the influence of applying gallium-aluminum-arsenide (GaAlAs laser (660Nm on the functional recovery of the sciatic nerve in rats. METHODS: The sciatic nerve of 12 Wistar rats was subjected to injury consisting of neurotmesis and epineural anastomosis. The rats were divided into two groups: control and laser therapy. After the injury, a GaAlAs laser was used (660Nm, 4J/cm², 26.3mW and 0.63cm² beam at three equidistant points on the injury, for 20 days. Footprint impressions were obtained from the animals before and seven, 14 and 21 days after the surgical procedure and the sciatic functional index (SFI was calculated
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Directory of Open Access Journals (Sweden)
Danilo Russo
2003-10-01
Full Text Available The barbastelle bat, <em>Barbastella barbastellusem> (Schreber, 1774 is a medium-sized, tree-dwelling vespertilionid classified as ?Endangered? in Italy; in western Europe it may be one of the rarest bat species. <em>B. barbastellusem> shows roosting preferences that should be regarded as a key point in conservation protocols. We examined roost selection in a breeding population of <em>B. barbastellusem> from the Abruzzo Lazio and Molise National Park (central Italy at three levels: woodland structure and management type; tree characteristics; and cavity characteristics. In 2001-2002, we fitted 31 adult <em>B. barbastellusem> (29 lactating females, one pregnant female and one male with 0.48g radio-tags and tracked them to their roost-trees. The bats were tracked for 4.5 ± 3.7 days (range: 0-12 days. We located 33 roosts used by 25 subjects (1.8±1.2 roosts/bat, range 1-5. The bats switched roosts frequently: 13 bats used more than one tree over the study period. A chi-square analysis showed that the roosts were not distributed at random across woodland categories: unmanaged woodland was positively selected, whereas shelterwood-harvested woodland was used in proportion to its availability, and ?pastures+scattered trees? was avoided. Twenty out of 33 roost trees were dead <em>Fagus sylvaticaem> trees; conversely, living <em>F. sylvaticaem> dominated in a tree sample obtained at random; dead trees were used more than expected (Χ² test, <em>P> <0.001. Overall, roost trees were significantly taller and had a larger diameter at breast?s height and more cavities than random trees; they also had a lower percent canopy closure than random trees. To highlight which variables were actually associated with selection, we devised a logistic regression model. The full model was significant (<em>P> <0.001; removal of tree type and tree height affected the model significantly, but the other variables did not produce detectable effects. The
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Synthesis and Sensory Evaluation of <em>ent>-Kaurane Diterpene Glycosides
Directory of Open Access Journals (Sweden)
Venkata Sai Prakash Chaturvedula
2012-07-01
Full Text Available Catalytic hydrogenation of the three <em>ent>-kaurane diterpene glycosides isolated from <em>Stevia rebaudianaem>, namely rubusoside, stevioside, and rebaudioside-A has been carried out using Pd(OH2 and their corresponding dihydro derivatives have been isolated as the products. Synthesis of reduced steviol glycosides was performed using straightforward chemistry and their structures were characterized on the basis of 1D and 2D NMR spectral data and chemical studies. Also, we report herewith the sensory evaluation of all the reduced compounds against their corresponding original steviol glycosides and sucrose for the sweetness property of these molecules.
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Coulomb explosion of H2 induced by a sub-10 fs intense laser pulse
International Nuclear Information System (INIS)
Saugout, S.
2006-12-01
This work presents an experimental and theoretical study of the interaction of H2 with an intense sub-10 fs-laser pulse. The ejection of the two electrons of the molecule by the laser pulse leads to the fragmentation of the physical sys em in two protons. This process is called Coulomb Explosion. The electronic and nuclear dynamics can be analyzed by measuring the kinetic energy spectra as a function of different laser parameters. This dynamics is also analyzed through a non-perturbative, double active electron theoretical model, based on the resolution of the time dependent Schroedinger equation. In this model, the internuclear distance is treated as a quantum variable. The experimental and theoretical results enlight the translation of the kinetic energy spectra towards a higher energy when the pulse duration decreases. Experimentally, laser pulses from 40 to 10 fs were used and down to 1 fs using theoretical simulations. This study shows that, for laser pulses shorter than 4 fs, the carrier envelope phase becomes a crucial parameter. Furthermore, the molecular dynamics of H2 in intense laser field is sensitive to the peak intensity of the pulse. The experimental and theoretical results show that, as the intensity increases, the kinetic energy spectra are centered around a higher energy. In addition, the presence of two double ionization regimes is theoretically demonstrated for a pulse duration of 4 fs. The H 2 molecule is also sensitive to the temporal shape of the laser pulse. This sensitivity allows for the detection of pre- or post-pulses by measuring the experimental kinetic energy spectra. Finally, the different double ionization processes are studied. The results show that the electron rescattering influences the femtosecond nuclear dynamics. (author)
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Reverse spontaneous laser line sweeping in ytterbium fiber laser
Czech Academy of Sciences Publication Activity Database
Navrátil, Petr; Peterka, Pavel; Honzátko, Pavel; Kubeček, V.
2017-01-01
Roč. 14, č. 3 (2017), č. článku 035102. ISSN 1612-2011 R&D Projects: GA ČR(CZ) GA16-13306S Institutional support: RVO:67985882 ; RVO:68378271 Keywords : laser line sweeping * ytterbium * fiber lasers Subject RIV: BH - Optics, Masers, Lasers; BH - Optics, Masers, Lasers (FZU-D) OBOR OECD: Optics (including laser optics and quantum optics); Optics (including laser optics and quantum optics) (FZU-D) Impact factor: 2.537, year: 2016
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FILTRAGEM DE NUVEM LASER PARA GERAÇÃO DE MDT POR KRIGAGEM
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Vanessa Jordão Marcato Fernandes
Full Text Available Esse artigo apresenta um método de filtragem de nuvem de pontos LASER para obtenção de um Modelo Digital de Terreno (MDT. O processo de filtragem é realizado com base em uma superfície aproximada gerada a partir de pontos amostrados sobre vias urbanas. Esses pontos são determinados por meio de linhas detectadas na imagem de intensidade do pulso laser via detector de Steger. A principal suposição do método é que o terreno tem um comportamento suave no interior das quadras e, dessa forma, os pontos amostrados ao longo das vias permitem, utilizando o método de interpolação por krigagem, uma representação adequada do terreno no interior das quadras, ou seja, relativamente próxima dos pontos LASER de terreno dessas regiões. Assim, a filtragem é realizada pela verificação da proximidade dos pontos da nuvem LASER original com a superfície aproximada gerada. Por fim, um MDT é obtido da nova amostra pelo método de interpolação por krigagem, melhorando a descrição da superfície. A partir dos experimentos realizados foi possível verificar a viabilidade do método proposto, com resultados de boa coerência visual e indicadores numéricos satisfatórios
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Ploidia de DNA em astrocitomas: estudo em 66 pacientes brasileiros
Directory of Open Access Journals (Sweden)
KRUTMAN-ZVEIBIL DEBORAH
1999-01-01
Full Text Available A determinação do conteúdo de DNA nuclear (fração de fase S e ploidia de DNA foi realizada por meio de análise de imagem em 66 astrocitomas, a partir de material fixado em formalina e seccionado em cortes de 5 micrômetros corados pela técnica de Feulgen. Nossos resultados mostraram forte relação entre a idade do paciente, grau histológico e sobrevida , com a ploidia de DNA e o percentual de células em fase de síntese. A análise da atividade proliferativa de astrocitomas intracranianos é a nosso ver muito útil no entendimento do comportamento biológico , do prognóstico e para o planejamento terapêutico dessas lesões.
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Monitores de diagnóstico em Mamografia : (Os 5MP em Portugal)
Timóteo, Maria Teresa
2012-01-01
O carcinoma da mama é o mais comum nas mulheres, em Portugal morrem cerca de 1500 mulheres por ano devido a esta patologia. Serviu o presente estudo para investigar se os Hospitais da Região de Lisboa e Vale do Tejo estão equipados, com monitores de diagnóstico em mamografia, que correspondam com as guidelines europeias. O serviço de Mamografia, em Portugal rege-se por estas guidelines, em que é referenciado que para um correcto diagnóstico, com toda a sensibilidade e especific...
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High-energy molecular lasers self-controlled volume-discharge lasers and applications
Apollonov, V V
2016-01-01
This book displays the physics and design of high-power molecular lasers. The lasers described are self-controlled volume-discharge lasers. The book explains self-sustained discharge lasers, self-initiated discharge lasers and technical approaches to laser design. Important topics discussed are laser efficiency, laser beam quality and electric field homogeneity. The book contains many new innovative applications.
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Are EM's communication tools effective? Evaluation research of two EM publications
International Nuclear Information System (INIS)
Wight, Evelyn; Gardner, Gene; Harvey, Tony
1992-01-01
As a reflection of its growing culture of openness, and in response to the public's need for accurate information about its activities, the U.S. Department of Energy (DOE) Office of the Assistant Secretary for Environmental Restoration and Waste Management (EM) has increased the amount of information available to the public through communication tools such as brochures, fact sheets, and a travelling exhibit with an interactive computer display. Our involvement with this effort has been to design, develop, and critique booklets, brochures, fact sheets and other communication tools for EM. This paper presents an evaluation of the effectiveness of two communication tools we developed: the EM Booklet and the EM Fact Sheets. We measured effectiveness using non-parametric testing. This paper describes DOE's culture change, EM's communication tools and their context within DOE'S new open culture, our research, test methods and results, the significance of our research, and our plans for future research. (author)
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Laser safety considerations for a mobile laser program
Flor, Mary
1997-05-01
An increased demand for advanced laser technology, especially in the area of cutaneous and cosmetic procedures has prompted physicians to use mobile laser services. Utilization of a mobile laser service allows physicians to provide the latest treatments for their patients while minimizing overhead costs. The high capital expense of laser systems is often beyond the financial means of individual clinicians, group practices, free-standing clinics and smaller community hospitals. Historically rapid technology turnover with laser technology places additional risk which is unacceptable to many institutions. In addition, health care reform is mandating consolidation of equipment within health care groups to keep costs at a minimum. In 1994, Abbott Northwestern Hospital organized an in-house mobile laser technology service which employs a group of experienced laser specialists to deliver and support laser treatments for hospital outreach and other regional physicians and health care facilities. Many of the hospital's internal safety standards and policies are applicable to the mobile environment. A significant challenge is client compliance because of the delicate balance of managing risk while avoiding being viewed as a regulator. The clinics and hospitals are assessed prior to service to assure minimum laser safety standards for both the patient and the staff. A major component in assessing new sites is to inform them of applicable regulatory standards and their obligations to assure optimum laser safety. In service training is provided and hospital and procedures are freely shared to assist the client in establishing a safe laser environment. Physician and nursing preceptor programs are also made available.
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Dermatological laser treatment
International Nuclear Information System (INIS)
Moerk, N.J.; Austad, J.; Helland, S.; Thune, P.; Volden, G.; Falk, E.
1991-01-01
The article reviews the different lasers used in dermatology. Special emphasis is placed on the treatment of naevus flammeus (''portwine stain'') where lasers are the treatment of choice. Argon laser and pulsed dye laser are the main lasers used in vascular skin diseases, and the article focuses on these two types. Copper-vapour laser, neodymium-YAG laser and CO 2 laser are also presented. Information is provided about the availability of laser technology in the different health regions in Norway. 5 refs., 2 figs
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Laser Ablation of Biological Tissue Using Pulsed CO2 Laser
International Nuclear Information System (INIS)
Hashishin, Yuichi; Sano, Shu; Nakayama, Takeyoshi
2010-01-01
Laser scalpels are currently used as a form of laser treatment. However, their ablation mechanism has not been clarified because laser excision of biological tissue occurs over a short time scale. Biological tissue ablation generates sound (laser-induced sound). This study seeks to clarify the ablation mechanism. The state of the gelatin ablation was determined using a high-speed video camera and the power reduction of a He-Ne laser beam. The aim of this study was to clarify the laser ablation mechanism by observing laser excision using the high-speed video camera and monitoring the power reduction of the He-Ne laser beam. We simulated laser excision of a biological tissue by irradiating gelatin (10 wt%) with radiation from a pulsed CO 2 laser (wavelength: 10.6 μm; pulse width: 80 ns). In addition, a microphone was used to measure the laser-induced sound. The first pulse caused ablation particles to be emitted in all directions; these particles were subsequently damped so that they formed a mushroom cloud. Furthermore, water was initially evaporated by laser irradiation and then tissue was ejected.
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Laser applications in nanotechnology: nanofabrication using laser ablation and laser nanolithography
International Nuclear Information System (INIS)
Makarov, G N
2013-01-01
The fact that nanoparticles and nanomaterials have fundamental properties different both from their constituent atoms or molecules and from their bulk counterparts has stimulated great interest, both theoretical and practical, in nanoparticles and nanoparticle-based assemblies (functional materials), with the result that these structures have become the subject of explosive research over the last twenty years or so. A great deal of progress in this field has relied on the use of lasers. In this paper, the directions followed and results obtained in laser nanotechnology research are reviewed. The parameters, properties, and applications of nanoparticles are discussed, along with the physical and chemical methods for their fabrication and investigation. Nanofabrication applications of and fundamental physical principles behind laser ablation and laser nanolithography are discussed in detail. The applications of laser radiation are shown to range from fabricating, melting, and evaporating nanoparticles to changing their shape, structure, size, and size distribution, through studying their dynamics and forming them into periodic arrays and various structures and assemblies. The historical development of research on nanoparticles and nanomaterials and the application of laser nanotechnology in various fields are briefly reviewed. (reviews of topical problems)
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Directory of Open Access Journals (Sweden)
Glaucio Serra Guimarães
2011-04-01
Full Text Available INTRODUÇÃO: as principais utilizações do laser argônio na Ortodontia são a redução do tempo de polimerização durante a colagem ortodôntica e o aumento da resistência à cárie do esmalte dentário. OBJETIVO: o objetivo deste trabalho foi avaliar as alterações químicas e morfológicas do esmalte dentário humano tratado com laser argônio nos parâmetros da colagem ortodôntica. MÉTODOS: quinze primeiros pré-molares hígidos, extraídos por indicação ortodôntica, foram selecionados e seccionados no sentido do longo eixo em dois segmentos iguais. Uma metade de cada elemento dentário foi tratada e a outra permaneceu sem tratamento. Um total de 30 amostras foi analisado, criando o grupo laser (n = 15 e o grupo controle (n = 15. O tratamento foi feito com laser argônio com 250mW de potência por 5 segundos, com densidade de energia de 8J/cm². RESULTADOS: a análise de difração de raios X demonstrou duas fases em ambos os grupos, as fases apatita e monetita. A redução da fase monetita foi significativa após o tratamento com laser, sugerindo maior cristalinidade. A análise de Espectroscopia de Energia Dispersiva (EDS indicou aumento na razão cálcio-fósforo no grupo laser, compatível com a diminuição da fase monetita. A morfologia superficial do esmalte dentário apresentou-se mais lisa após o tratamento com laser argônio. CONCLUSÕES: o aumento de cristalinidade e a lisura superficial do esmalte no grupo laser são fatores sugestivos de aumento de resistência à cárie no esmalte dentário.INTRODUCTION: The main utilities of the argon laser in orthodontics are the high speed curing process in orthodontic bonding and the caries resistance promotion of the tooth enamel. OBJECTIVE: The objective of this study was to evaluate the chemical and morphological changes in the tooth enamel treated with the argon laser in the orthodontic bonding parameters. METHODS: Fifteen sound human first premolars, removed for orthodontic
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Laser spectroscopy and laser isotope separation of atomic gadolinium
International Nuclear Information System (INIS)
Chen, Y. W.; Yamanaka, C.; Nomaru, K.; Kou, K.; Niki, H.; Izawa, Y.; Nakai, S.
1994-01-01
Atomic vapor laser isotope separation (AVLIS) is a process which uses intense pulsed lasers to selectively photoionize one isotopic species of a chemical element, after which these ions are extracted electromagnetically. The AVLIS has several advantages over the traditional methods based on the mass difference, such as high selectivity, low energy consumption, short starting time and versatility to any atoms. The efforts for atomic vapor laser isotope separation at ILT and ILE, Osaka University have been concentrated into the following items: 1) studies on laser spectroscopy and laser isotope separation of atomic gadolinium, 2) studies on interaction processes including coherent dynamics, propagation effects and atom-ion collision in AVLIS system, 3) development of laser systems for AVLIS. In this paper, we present experimental results on the laser spectroscopy and laser isotope separation of atomic gadolinium.
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International Nuclear Information System (INIS)
Lee, Baek Yeon
2007-01-01
This book mentions laser processing with laser principle, laser history, laser beam property, laser kinds, foundation of laser processing such as laser oscillation, characteristic of laser processing, laser for processing and its characteristic, processing of laser hole including conception of processing of laser hole and each material, and hole processing of metal material, cut of laser, reality of cut, laser welding, laser surface hardening, application case of special processing and safety measurement of laser.
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Alves, Ana Paula de Faria; Santos, Janine V.; Neves, Laudelina B.; Sereia, Maria Josiane
2008-01-01
Foi realizada avaliação comparativa da retenção da vitamina C (ácido Ascórbico – AA) em suco fresco de laranjas íntegras, suco de laranja estocada sob refrigeração e em bolo contendo suco de laranja após a cocção em forno culinário convencional. O teor de AA em suco de laranjas armazenadas sob refrigeração por oito semanas variou entre 74,94 e 51,55 mg% com taxa de redução de 0,92% ao dia. Em suco fresco de laranja armazenado sob refrigeração durante sete dias, o teor médio de AA foi de 49,62...
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Directory of Open Access Journals (Sweden)
Lei Zhang
2012-09-01
Full Text Available By introducing long carbon-chain alkyl groups at the C-13 position of berberine and palmatine, 13-<em>n>-hexyl/13-<em>n>-octyl berberine and palmatine chloride analogues 4a–d were synthesized and examined by MTT assays for cytotoxic activity in seven human cancer cell lines (7701QGY, SMMC7721, HepG2, CEM, CEM/VCR, KIII, Lewis, yielding IC50 values of 0.02 ± 0.01–13.58 ± 2.84 μM. 13-<em>n>-Octyl palmatine (compound 4d gave the most potent inhibitor activity, with an IC50 of 0.02 ± 0.01 μM for SMMC7721. In all cases, the 13-<em>n>-alkyl berberine and palmatine analogues 4a–d were more cytotoxic than berberine and palmatine. In addition, compounds 4a–d also exhibited more potent cytotoxicity than berberine and palmatine in mice with S180 sarcoma xenografted<em> in vivoem>. The primary screening results indicated that the 13-<em>n>-hexyl/13-<em>n>-octyl berberine and palmatine analogues might be valuable source for new potent anticancer drug candidates.
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Directory of Open Access Journals (Sweden)
Gen-Chun Wang
2012-07-01
Full Text Available Through bioassay-guided fractionation of the extracts from the aerial parts of the Chinese herb <em>Hypericum japonicumem> Thunb. Murray, Isojacareubin (ISJ was characterized as a potent antibacterial compound against the clinical methicillin-resistant S<em>taphylococcus aureusem> (MRSA. The broth microdilution assay was used to determine the minimal inhibitory concentrations (MICs and minimal bactericidal concentrations (MBCs of ISJ alone. The results showed that its MICs/MBCs ranged from 4/16 to 16/64 μg/mL, with the concentrations required to inhibit or kill 50% of the strains (MIC50/MBC50 at 8/16 μg/mL. Synergistic evaluations of this compound with four conventional antibacterial agents representing different types were performed by the chequerboard and time-kill tests. The chequerboard method showed significant synergy effects when ISJ was combined with Ceftazidime (CAZ, Levofloxacin (LEV and Ampicillin (AMP, with the values of 50% of the fractional inhibitory concentration indices (FICI50 at 0.25, 0.37 and 0.37, respectively. Combined bactericidal activities were also observed in the time-kill dynamic assay. The results showed the ability of ISJ to reduce MRSA viable counts by log10CFU/mL at 24 h of incubation at a concentration of 1 × MIC were 1.5 (LEV, additivity, 0.92 (CAZ, indifference and 0.82 (AMP, indifference, respectively. These <em>in vitroem> anti-MRSA activities of ISJ alone and its synergy with conventional antibacterial agents demonstrated that ISJ enhanced their efficacy, which is of potential use for single and combinatory therapy of patients infected with MRSA.
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Directory of Open Access Journals (Sweden)
Andrea Schmitt
2013-01-01
Full Text Available Esquizofrenia é uma severa doença neurobiológica com fatores genéticos e ambientais desempenhando um papel na fisiopatologia. Diversas regiões cerebrais têm sido implicadas no processo da doença e estão conectadas em complexos circuitos neuronais. Nos níveis molecular e celular, a conectividade afetada entre essas regiões, envolvendo mielinização disfuncional dos axônios neuronais, bem como as alterações no nível sináptico e metabolismo energético levando a distúrbios na plasticidade sináptica, são os maiores achados em estudos post-mortem. Estudos de microarranjos investigando a expressão gênica contribuíram para os achados de alterações em vias complexas em regiões cerebrais relevantes na esquizofrenia. Além disso, estudos utilizando microdissecção e captura a laser permitiram a investigação da expressão gênica em grupos específicos de neurônios. Entretanto, deve ser mantido em mente que em estudos post-mortem, confusos efeitos de medicação, qualidade de RNAm, bem como capacidade de mecanismos regenerativos neuroplásticos do cérebro em indivíduos com história de vida de esquizofrenia, podem influenciar o complexo padrão de alterações no nível molecular. Apesar dessas limitações, estudos transcriptômicos livres de hipóteses em tecido cerebral de pacientes esquizofrênicos oferecem uma possibilidade única para aprender mais sobre os mecanismos subjacentes, levando a novas ópticas da fisiopatologia da doença.Schizophrenia is a severe neurobiological disease with genetic and environmental factors playing a role in the pathophysiology. Several brain regions have been implicated in the disease process and are connected in complex neuronal circuits. On the cellular and molecular level, affected connectivity between these regions, involving dysfunctional myelination of neuronal axons, as well as alterations on the synaptic level and energy metabolism of neurons leading to disturbances in synaptic
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Directory of Open Access Journals (Sweden)
Andrea Schmitt
2012-01-01
Full Text Available Esquizofrenia é uma severa doença neurobiológica com fatores genéticos e ambientais desempenhando um papel na fisiopatologia. Diversas regiões cerebrais têm sido implicadas no processo da doença e estão conectadas em complexos circuitos neuronais. Nos níveis molecular e celular, a conectividade afetada entre essas regiões, envolvendo mielinização disfuncional dos axônios neuronais, bem como as alterações no nível sináptico e metabolismo energético levando a distúrbios na plasticidade sináptica, são os maiores achados em estudos post-mortem. Estudos de microarranjos investigando a expressão gênica contribuíram para os achados de alterações em vias complexas em regiões cerebrais relevantes na esquizofrenia. Além disso, estudos utilizando microdissecção e captura a laser permitiram a investigação da expressão gênica em grupos específicos de neurônios. Entretanto, deve ser mantido em mente que em estudos post-mortem, confusos efeitos de medicação, qualidade de RNAm, bem como capacidade de mecanismos regenerativos neuroplásticos do cérebro em indivíduos com história de vida de esquizofrenia, podem influenciar o complexo padrão de alterações no nível molecular. Apesar dessas limitações, estudos transcriptômicos livres de hipóteses em tecido cerebral de pacientes esquizofrênicos oferecem uma possibilidade única para aprender mais sobre os mecanismos subjacentes, levando a novas ópticas da fisiopatologia da doença.Schizophrenia is a severe neurobiological disease with genetic and environmental factors playing a role in the pathophysiology. Several brain regions have been implicated in the disease process and are connected in complex neuronal circuits. On the cellular and molecular level, affected connectivity between these regions, involving dysfunctional myelination of neuronal axons, as well as alterations on the synaptic level and energy metabolism of neurons leading to disturbances in synaptic
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Electrodeless excimer laser; Laser a eccimeri senza elettrodi
Energy Technology Data Exchange (ETDEWEB)
Lisi, N. [ENEA, Divisione Nuovi Materiali, Centro Ricerche Casaccia, Rome (Italy)
2001-07-01
In this paper it is proposed how to build an excimer laser based on an electrodeless discharge (or Dielectric Barrier Discharge). Such laser could operate with a low energy per pulse (<100 mJ) and a high repetition rate (<100 kHz). The most relevant advantage an electrodeless DBD laser is the much longer gas mixture lifetime. This feature could allow the operation of a sealed laser emitting higher average power with respect to commercially available excimer lasers. Such discharge scheme could be advantageous in order to excite the F{sub 2} excimer molecule, whose emission wavelength in the VUV range (157 nm) at high reprate is particularly interesting in the micro-lithography field. [Italian] In questo documento viene proposto come costruire un laser a eccimeri basato su una scarica priva di elettrodi, o Dielectric Barrier Discharge. Tale laser puo' funzionare con una bassa energia per impulso (<100 mJ) ad alta frequenza di ripetizione (<100 kHz). Il vantaggio fondamentale di un laser a DBD e quindi privo di elettrodi e' la vita media della miscela gassosa molto piu' alta che potrebbe permettere alla camera laser di operare sigillata ad una potenza media superiore a quella dei laser a eccimeri attuali. Tale schema di pompaggio potrebbe essere particolarmente vantaggioso per eccitare la molecola eccimero F{sub 2} la cui lunghezza di emissione nel VUV (157 nm) ad elevata frequenza di ripetizione presenta un notevole interesse nel campo della produzione di microcircuiti.
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Prevalência e fatores associados à obesidade abdominal em pacientes em hemodiálise em Goiânia - GO
Directory of Open Access Journals (Sweden)
Ana Tereza Vaz de Souza Freitas
2013-12-01
Full Text Available INTRODUÇÃO: A presença de excesso de peso, especialmente obesidade visceral, contribui para o maior risco de complicações metabólicas e cardiovasculares em pacientes com doença renal crônica. OBJETIVO: Determinar a prevalência e os fatores associados à obesidade abdominal em pacientes em hemodiálise (HD. MÉTODOS: Estudo transversal com 344 pacientes maiores de 18 anos. A obesidade abdominal foi definida pela circunferência da cintura > 94 cm nos homens e > 80 cm nas mulheres. As variáveis independentes envolveram aspectos socioeconômicos, demográficos, hábitos de vida, tempo em HD, consumo alimentar e índice de massa corporal (IMC. A análise dos fatores associados foi realizada por regressão de Poisson múltipla, permanecendo no modelo final as variáveis com p 25 kg/m². Nos homens, a classe econômica D/E também permaneceu associada à obesidade abdominal, p < 0,05. CONCLUSÃO: Observou-se alta prevalência de obesidade abdominal em pacientes em hemodiálise. Idade superior a 40 anos, classes econômicas mais baixas, ingestão proteica inferior ao recomendado e excesso de peso foram associados à obesidade abdominal.
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Laser technologies for laser accelerators. Annual report
International Nuclear Information System (INIS)
1985-01-01
The primary result of the work reported is the determination of laser system architectures that satsify the requirements of high luminosity, high energy (about 1 TeV), electron accelerators. It has been found that high laser efficiency is a very hard driver for these accelerators as the total average laser output optical power is likely to fall above 10 MW. The luminosity requires rep rates in the kHz range, and individual pulse lengths in the 1-10 psec range are required to satisfy acceleration gradient goals. CO 2 and KrF lasers were chosen for study because of their potential to simultaneously satisfy the given requirements. Accelerator luminosity is reviewed, and requirements on laser system average power and rep rate are determined as a function of electron beam bunch parameters. Laser technologies are reviewed, including CO 2 , excimers, solid state, and free electron lasers. The proposed accelerator mechanisms are summarized briefly. Work on optical transport geometries for near and far field accelerators are presented. Possible exploitation of the CO 2 and DrF laser technology to generate the required pulse lengths, rep rates, and projected efficiencies is illustrated and needed development work is suggested. Initial efforts at developing a 50 GeV benchmark conceptual design and a 100 MeV demonstration experiment conceptual design are presented
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Directory of Open Access Journals (Sweden)
Letícia Helena Theodoro
2002-12-01
Full Text Available The purpose of this study was to morphologically evaluate, by means of scanning electron microscopy, the effects of Er:YAG laser on the treatment of root surfaces submitted to scaling and root planing with conventional periodontal instruments. Eighteen root surfaces (n = 18, which had been previously scaled and planed, were assigned to 3 groups (n = 6. The control Group (G1 received no further treatment; Group 2 (G2 was irradiated with Er:YAG laser (2.94 mum, with 47 mJ/10 Hz, in a focused mode with air/water spray during 15 s and with 0.57 J/cm² of fluency per pulse; Group 3 (G 3 was irradiated with Er:YAG laser (2.94 mum, with 83 mJ/10 Hz, in a focused mode with air/water spray during 15 s and with 1.03 J/cm² of fluency per pulse. We concluded that the parameters adopted for Group 3 removed the smear layer from the root surface, exposing the dentinal tubules. Although no fissures, cracks or carbonized areas were observed, an irregular surface was produced by Er:YAG laser irradiation. Thus, the biocompatibility of the irradiated root surface, within the periodontal healing process, must be assessed.O objetivo do presente estudo foi analisar morfologicamente, através de microscopia eletrônica de varredura, os efeitos do laser de Er:YAG no tratamento de superfícies radiculares submetidas à raspagem e aplainamento radicular com instrumentos manuais. Foram utilizados 18 espécimes (n = 18 de superfícies radiculares que após ser submetidos à raspagem e aplainamento radicular foram divididos em 3 grupos (n = 6. O grupo controle (G1 não sofreu nenhum tratamento; Grupo 2 (G2 foi irradiado com laser de Er:YAG (2,94 mim 47 mJ/10 Hz, focalizado,com refrigeração à água durante 15 s e fluência de pulso de 0,57 J/cm²; Grupo 3 (G3 foi irradiado com laser de Er:YAG (2,94 mim, 83 mJ/10 Hz, focalizado, com refrigeração à agua durante 15 s e fluência de pulso de 1,03 J/cm². Através da análise dos resultados podemos concluir que o laser de
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Energy Technology Data Exchange (ETDEWEB)
Bykovskij, Yu
1979-02-01
The characteristics a laser source of multiply-ionized ions are described with regard to the interaction of laser radiation and matter, ion energy spectrum, angular ion distribution. The amount of multiple-ionization ions is evaluated. Out of laser source applications a laser injector of multiple-ionization ions and nuclei, laser mass spectrometry, laser X-ray microradiography, and a laser neutron generators are described.
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Energy Technology Data Exchange (ETDEWEB)
Blay, Alberto
2001-07-01
The purpose of this study is to determine whether the process of bone integration of implants placed in rabbit tibia is changed in any way if the region is radiated with laser, as compared to the time required for the bone integration process without radiation. Thirty adult male white New Zealand rabbits were submitted to implant surgery, for subsequent evaluation of the removal torque and resonance frequency. Each animal received two implants of pure titanium, one in each proximal metaphysics of the tibia, which were inserted with a 40 Ncm torque, and their initial stability was also monitored by means of a resonance frequency analyzer. The rabbits were then divided into 3 groups: one control group and two laser groups. The groups were evaluated in regard to removal torque and resonance frequency of the implants, after 3 and 6 weeks. One of the laser groups was radiated with a laser beam of a wavelength in the infrared range (830 nm) and the other group was radiated with a laser beam emitted in the visible range (680 nm). Ten radiation sessions were performed, 48 hours apart, the first of them during the immediate post-operation period. Radiation energy density was 4 J/cm{sup 2} per point, and there were two points at each side of the tibia. Results of the statistical analysis of the resonance frequency indicated that for both laser groups there was a significant difference between frequency values at the time of implant and the values obtained after 3 and 6 weeks. Furthermore, the results obtained for the removal torque of the three groups showed a statistically significant difference after a period of 6 weeks; removal torque values for the laser groups were, in the average, much greater than those of the control group. From these results it is possible to conclude that implants in rabbit tibia, that were exposed to laser radiation with wavelengths of 680 nm and 830 nm, had a better degree of bone integration than the control group.(author)
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Variabilità microsatellitare in popolazioni italiane di martora, <em>Martes martesem>
Directory of Open Access Journals (Sweden)
Licia Colli
2003-10-01
Full Text Available La martora, <em>Martes martesem>, è un mustelide storicamente presente su gran parte del territorio italiano, soprattutto dove siano presenti foreste mature altamente strutturate e ricche di risorse. Nel corso dei decenni passati, cause quali la deforestazione con conseguente frammentazione dell'habitat, la caccia e la persecuzione da parte dell'uomo hanno portato ad un sensibile declino sia nel numero d'individui sia di popolazioni in tutta l'Europa. Frammentazione degli areali e diminuzione del numero di soggetti costituiscono le cause principali di un limitato flusso genico con conseguente formazione di popolazioni isolate di martora e perdita di variabilità genetica (Kyle <em>et al.em>, 2003. Per queste ragioni la martora risulta attualmente tutelata secondo quanto previsto dalla Convenzione di Berna (appendice III e dalla Direttiva europea 92/43/CEE "Habitats & Species". Di fronte a prospettive di tipo conservazionistico, diventa necessario disporre di metodologie per la valutazione della variabilità residua nella specie a livello d'individui e di popolazioni. Secondo numerosi Autori, i microsatelliti costituiscono marcatori molto efficaci nella descrizione della struttura genetica e della storia demografica di specie (Beaumont & Bruford, 1999; Linares, 1999. Il presente lavoro propone i risultati ottenuti attraverso il confronto di due campioni costituiti da individui di <em>Martes martesem> provenienti dalla Sardegna (25 esemplari e dal territorio italiano (6 esemplari. L'analisi è stata condotta a livello di 7 loci microsatellitari dinucleotidici polimorfici. Il valore di FST calcolato dal confronto dei due gruppi è risultato pari a 0,102 e ricade nel <em>range> di variazione identificato di recente in popolazioni nord-europee di martora (Kyle <em>et al.em>, 2003. L'analisi della varianza molecolare (AMOVA, condotta a due livelli gerarchici, ha permesso in particolare di ripartire la varianza del campione
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Laser Physics and Physics with Lasers - Recent Advances
International Nuclear Information System (INIS)
Marowsky, G.
2008-01-01
This contribution reviews the development as well as recent technological advances in the field of optics with lasers and laser-related applications. Topics ranging from 'attoscience' to 'zero-modes' shall be dealt with in this presentation. Further reading in the following references is suggested: Springer Handbook of Lasers and Optics (F. Trager, ed.), 2007, ISBN-13: 978-0-387-95579-7; Chapter 11.7, Part C: Ultraviolet Lasers: Excimers, Fluorine (F2), Nitrogen (N2), pp. 764-776; Excimer Laser Technology (D. Basting, G. Marowsky, eds.) 2005, Springer, ISBN-13 978-3-540-20056-7
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LASER PROCESSING ON SINGLE CRYSTALS BY UV PULSE LASER
龍見, 雅美; 佐々木, 徹; 高山, 恭宜
2009-01-01
Laser processing by using UV pulsed laser was carried out on single crystal such as sapphire and diamond in order to understand the fundamental laser processing on single crystal. The absorption edges of diamond and sapphire are longer and shorter than the wave length of UV laser, respectively. The processed regions by laser with near threshold power of processing show quite different state in each crystal.
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Directory of Open Access Journals (Sweden)
Luiz Carlos Oliveira Junior
Full Text Available resumo O artigo aborda aspectos da relação do cinema com a arte do retrato. Buscamos, em primeiro lugar, uma definição estética do que seria um retrato cinematográfico, sempre em tensão com os critérios formais e padrões estilísticos que historicamente constituíram o retrato pictórico. Em seguida, relacionamos essa questão com a importância que se deu à representação do close-up de rosto nas primeiras décadas do cinema, quando foi atribuído aos filmes um papel inédito no estudo da fisionomia e da expressão facial. Por fim, apresentamos exemplos de autorretratos na pintura e no cinema para expor a forma como a autorrepresentação põe em crise as noções de subjetividade e identidade em que a definição clássica do retrato se apoiava.
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Directory of Open Access Journals (Sweden)
Paolo Debernardi
1991-07-01
Full Text Available Abstract The diet of the Fox <em>Vulpes vulpesem> was studied by the analysis of 157 gastric contents coming from hilly areas of the Province of Cuneo. Samples were gathered during January-March of the years '86 (N. 41, '87 (N. 72 and '88 (N. 44. The mean percentage of frequency was determined for the following feeding categories: Fruits (26.1%, Other vegetable components (19.7%, Insects (2.5%, Wild birds (11.5%, Insectivores and Rodents (42.7%, <em>Lepus capensisem> (13.4%, Indeterminate Lagomorphs (17.2%, Domestic animals (59.2% and Other (2.5%. The diet is analysed in relation to some available trophic resources (dumps, restoking of hares and of pheasants. Riassunto Vengono presentati i dati dell'analisi di 157 contenuti gastrici di <em>Vulpes vulpesem>, provenienti da aree collinari della provincia di Cuneo; i campioni si riferiscono ai primi tre mesi delle annate '86 (N. 41, '87 (N. 72 e '88 (N. 44. Sono state determinate le frequenze percentuali delle seguenti categorie alimentari: Frutti (26,1%, Altre componenti vegetali (19,7%, Insetti (2,5%, Uccelli selvatici (11,5%, Insettivori e Roditori (42,7%, <em>Lepus capensisem> (13,4%, Lagomorfi indeterminati (17,2%, Animali domestici (59,2% e Altro (2,5%. La dieta viene esaminata in relazione ad alcuni aspetti legati alle disponibilità trofiche del territorio (presenza di discariche, ripopolamenti di selvaggina.
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Design windows of laser fusion power plants and conceptual design of laser-diode pumped slab laser
International Nuclear Information System (INIS)
Kozaki, Y.; Eguchi, T.; Izawa, Y.
1999-01-01
An analysis of the design space available to laser fusion power plants has been carried out, in terms of design key parameters such as target gain, laser energy and laser repetition rate, the number of fusion react ion chambers, and plant size. The design windows of economically attractive laser fusion plants is identified with the constraints of key design parameters and the cost conditions. Especially, for achieving high repetition rate lasers, we have proposed and designed a diode-pumped solid-state laser driver which consists of water-cooled zig-zag path slab amplifiers. (author)
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Milonni, Peter W
1988-01-01
A comprehensive introduction to the operating principles and applications of lasers. Explains basic principles, including the necessary elements of classical and quantum physics. Provides concise discussions of various laser types including gas, solid state, semiconductor, and free electron lasers, as well as of laser resonators, diffraction, optical coherence, and many applications including holography, phase conjugation, wave mixing, and nonlinear optics. Incorporates many intuitive explanations and practical examples. Discussions are self-contained in a consistent notation and in a style that should appeal to physicists, chemists, optical scientists and engineers.
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Development of laser materials processing and laser metrology techniques
International Nuclear Information System (INIS)
Kim, Cheol Jung; Chung, Chin Man; Kim, Jeong Mook; Kim, Min Suk; Kim, Kwang Suk; Baik, Sung Hoon; Kim, Seong Ouk; Park, Seung Kyu
1997-09-01
The applications of remote laser materials processing and metrology have been investigated in nuclear industry from the beginning of laser invention because they can reduce the risks of workers in the hostile environment by remote operation. The objective of this project is the development of laser material processing and metrology techniques for repairing and inspection to improve the safety of nuclear power plants. As to repairing, we developed our own laser sleeve welding head and innovative optical laser weld monitoring techniques to control the sleeve welding process. Furthermore, we designed and fabricated a 800 W Nd:YAG and a 150 W Excimer laser systems for high power laser materials processing in nuclear industry such as cladding and decontamination. As to inspection, we developed an ESPI and a laser triangulation 3-D profile measurement system for defect detection which can complement ECT and UT inspections. We also developed a scanning laser vibrometer for remote vibration measurement of large structures and tested its performance. (author). 58 refs., 16 tabs., 137 figs
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Development of short pulse laser pumped x-ray lasers
International Nuclear Information System (INIS)
Dunn, J; Osterheld, A L; Hunter, J R; Shlyaptsev, V N
2000-01-01
X-ray lasers have been extensively studied around the world since the first laboratory demonstration on the Novette laser at LLNL in 1984 [l]. The characteristic properties of short wavelength, high monochromaticity, collimation and coherence make x-ray lasers useful for various applications. These include demonstrations of biological imaging within the water window, interferometry of laser plasmas and radiography of laser-heated surfaces. One of the critical issues has been the high power pump required to produce the inversion. The power scaling as a function of x-ray laser wavelength follows a -k4 to law. The shortest x-ray laser wavelength of ∼ 35 (angstrom) demonstrated for Ni-like All was at the limit of Nova laser capabilities. By requiring large, high power lasers such as Nova, the shot rate and total number of shots available have limited the rapid development of x-ray lasers and applications. In fact over the last fifteen years the main thrust has been to develop more efficient, higher repetition rate x-ray lasers that can be readily scaled to shorter wavelengths. The recent state of progress in the field can be found in references. The objective of the project was to develop a soft x-ray laser (XRL) pumped by a short pulse laser of a few joules. In effect to demonstrate a robust, worlung tabletop x-ray laser at LLNL for the first time. The transient collisional scheme as proposed by Shlyaptsev et al [8, 9] was the candidate x-ray laser for study. The successful endeavour of any scientific investigation is often based upon prudent early decisions and the choice of this scheme was both sound and fruitful. It had been demonstrated very recently for Ne-like Ti at 326 A using a small tabletop laser [10] but had not yet reached its full potential. We chose this scheme for several reasons: (a) it was a collisional-type x-ray laser which has been historically the most robust; (b) it had the promise of high efficiency and low energy threshold for lasing; (c) the
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Directory of Open Access Journals (Sweden)
Tatiana Sacks
2004-12-01
Full Text Available Os autores apresentam dois casos de reações alérgicas relacionadas a tatuagens, em que o laser e a luz pulsada de alta energia tiveram papel fundamental na indução e no tratamento dessas reações. No primeiro, houve surgimento de lesão eczematosa no local do pigmento vermelho utilizado na tatuagem. Após várias tentativas terapêuticas, a luz pulsada de alta energia foi utilizada com sucesso na remoção do pigmento e desaparecimento dos sintomas. No segundo, os autores demonstram um caso de reação anafilática induzida pelo laser Nd:YAG de pulso longo.The authors describe two cases of allergic reactions related to tattoos, in which laser and intense pulsed light had an important role in inducing and treating these allergic reactions. In the first case, the patient developed eczematous lesions at the site of the red pigment used in tattooing. After several unsuccessful therapeutic attempts, intense pulsed light was used. It successfully removed the red pigment and treated the allergy symptoms. In the second case, the authors describe a case of anaphylactic reaction precipitated by the long pulse Nd:YAD laser.
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Energy Technology Data Exchange (ETDEWEB)
Radaelli, Claudia Amaral Rabello de Mello
2002-07-01
High success rates are achieved in conventional endodontic treatment of vital pulp teeth. However, in cases of non-vital pulp, a decrease in the rate of success occurs due to difficulties in achieving a complete disinfection of the root canals system. Some bacteria, such as Enterococcus faecalis, are frequently found in cases of endodontic treatment failure due to their high resistance to the conventional endodontic treatment. The aim of this study was to evaluate the efficiency of a high power diode laser irradiation in bacterial reduction of contaminated canals associated with dressing compose by calcium hydroxide paste propylene glycol and camphorated paramonochlorophenol. Eighty-two root canals were infected in vitro with Enterococcus faecalis in a concentration of 1x10{sup 8} CFU/ml. Specimens were high intensity irradiated with a diode laser model Opus 10, at a wavelength of 830 nm. Two different parameters were employed in continuous mode: 3 W and 2,5 W with a 360 {mu}m optical fiber at an angle of approximately 5 degrees respect to the dentine surface during 5 seconds, in 4 applications, with 20 seconds intervals among them. After these proceedings specimens were vortexed in peptone water and dilutions performed. Aliquots of the dilution were plated on m-Enterococcus agar, incubated, and the Colonies Forming Units (CFU) of ali groups was counted. The results showed a significant reduction of bacteria on ali groups after laser irradiation. A high reduction rate was achieved: 98.5% immediately after the laser irradiation; 48 hours after, the reduction was of 96,73% and, finally, a 100% reduction was achieved through the combination of laser irradiation and a long lasting dressing of calcium hydroxide paste, propylene glycol and camphorated paramonochlorophenol. High rates of bacteria reduction were achieved using the parameter of 3 W in continuous mode with the power of 2,9473 KW/cm{sup 2}. The temperature was monitored with a K-pipe thermocouple placed at
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Directory of Open Access Journals (Sweden)
Denise Araújo Lapa Pedreira
2005-12-01
ície placentária. Aqueles vasos identificados como responsáveis pela transfusão foram coagulados através do laser. O procedimento combina a ultra-sonografia e a fetoscopia, no que se denomina uma abordagem sono-endoscópica (FETENDO. RESULTADOS: Dentre as oito gestações avaliadas, o procedimento foi realizado em cinco casos (10 fetos. Todos os fetos sobreviveram por um período mínimo de cinco semanas após a cirurgia. Na evolução, oito fetos nasceram vivos e cinco sobreviveram ao período neonatal. No seguimento pós-natal de 18 meses, todos os cinco estão vivos e bem, tendo atualmente uma idade média de 10,6 meses. A sobrevida geral foi de 50%, sendo que em três gestações, pelo menos um feto sobreviveu. CONCLUSÕES: A fetoscopia com laser é atualmente considerada "gold-standard" no tratamento da STT. No entanto, a técnica é sofisticada e depende de treinamento adequado. Nosso serviço é o primeiro do país a oferecer esta técnica cirúrgica e nossos índices de sucesso se comparam aos índices mundiais.
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Directory of Open Access Journals (Sweden)
M.F. Caliendo
2003-10-01
Full Text Available In Italia il Cinghiale ha subito varie oscillazioni numeriche per immissioni d?esemplari provenienti soprattutto dall'est europeo o da paesi vicini (Massei & Toso, 1993 e incrocio con esemplari di maiale domestico, allevato allo stato brado o semi brado in molte zone d'Italia (Apollonio <em>et al.em>, 1988. Questi fattori sono stati responsabili anche di un impoverimento genetico della forma autoctona italiana <em>Sus scrofa meridionalisem> e <em>majori> che sembrano persistere solo in Sardegna e Maremma (Apollonio <em>et al.em>, 1988. Tra le riserve in cui si ritiene possano trovarsi popolazioni ancora integre, figura la tenuta presidenziale di Castelporziano (Roma. Prendendo spunto da questo lavoro, con il nostro contributo riportiamo i risultati, a livello genetico, della ibridazione con il maiale da parte di cinghiali della Campania, basato sul DNA microsatellite di 4 loci polimorfi. Sono state studiate 9 popolazioni (allevate e libere, usando per riferimenti maiali allo stato brado e cinghiali di Castelporziano. Dall?analisi delle frequenze alleliche è stato eseguito il <em>test di assignmentem> (implementato in una sub routine del software Arlequin 2.0 che individua la possibile origine di un individuo, rispetto ad una rosa di probabili popolazioni di riferimento (Paetkau <em>et al.em>, 1998. Con i risultati del test di assignment si è costruito il grafico <em>log-log genotypeem>, rappresentato da un piano individuato dalle due variabili di riferimento (cinghiale e maiale brado. Le popolazioni esaminate evidenziano una generalizzata distribuzione a cavallo tra i due riferimenti con individui geneticamente simili al cinghiale ed altri al maiale. Questa ripartizione simmetrica è molto evidente nel caso dei cinghiali catturati a Punta Licosa e in quelli dell?allevamento di Polla. La distribuzione dei genotipi sul piano è spesso dispersa, ad eccezione dei cinghiali della Valle del Vento e quelli di Monteverde (individui
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Laser-supported detonation waves and pulsed laser propulsion
International Nuclear Information System (INIS)
Kare, J.
1990-01-01
A laser thermal rocket uses the energy of a large remote laser, possibly ground-based, to heat an inert propellant and generate thrust. Use of a pulsed laser allows the design of extremely simple thrusters with very high performance compared to chemical rockets. The temperatures, pressures, and fluxes involved in such thrusters (10 4 K, 10 2 atmospheres, 10 7 w/cm 2 ) typically result in the creation of laser-supported detonation (LSD) waves. The thrust cycle thus involves a complex set of transient shock phenomena, including laser-surface interactions in the ignition of the LSD wave, laser-plasma interactions in the LSD wave itself, and high-temperature nonequilibrium chemistry behind the LSD wave. The SDIO Laser Propulsion Program is investigating these phenomena as part of an overall effort to develop the technology for a low-cost Earth-to-orbit laser launch system. We will summarize the Program's approach to developing a high performance thruster, the double-pulse planar thruster, and present an overview of some results obtained to date, along with a discussion of the many research question still outstanding in this area
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ND:GLASS LASER DESIGN FOR LASER ICF FISSION ENERGY (LIFE)
International Nuclear Information System (INIS)
Caird, J.A.; Agrawal, V.; Bayramian, A.; Beach, R.; Britten, J.; Chen, D.; Cross, R.; Ebbers, C.; Erlandson, A.; Feit, M.; Freitas, B.; Ghosh, C.; Haefner, C.; Homoelle, D.; Ladran, T.; Latkowski, J.; Molander, W.; Murray, J.; Rubenchik, S.; Schaffers, K.; Siders, C.W.; Stappaerts, E.; Sutton, S.; Telford, S.; Trenholme, J.; Barty, C.J.
2008-01-01
We have developed preliminary conceptual laser system designs for the Laser ICF (Inertial Confinement Fusion) Fission Energy (LIFE) application. Our approach leverages experience in high-energy Nd:glass laser technology developed for the National Ignition Facility (NIF), along with high-energy-class diode-pumped solid-state laser (HEC-DPSSL) technology developed for the DOE's High Average Power Laser (HAPL) Program and embodied in LLNL's Mercury laser system. We present laser system designs suitable for both indirect-drive, hot spot ignition and indirect-drive, fast ignition targets. Main amplifiers for both systems use laser-diode-pumped Nd:glass slabs oriented at Brewster's angle, as in NIF, but the slabs are much thinner to allow for cooling by high-velocity helium gas as in the Mercury laser system. We also describe a plan to mass-produce pump-diode lasers to bring diode costs down to the order of $0.01 per Watt of peak output power, as needed to make the LIFE application economically attractive
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Pré-resfriamento em água de lichia 'B3' mantida em armazenamento refrigerado
del Aguila,Juan Saavedra; Hofman,Peter; Campbell,Terrence; Marques,José Roberto; Heiffig-del Aguila,Lília Sichmann; Kluge,Ricardo Alfredo
2009-01-01
Este experimento visou a estudar o efeito de diferentes temperaturas e tempos de pré-resfriamento em água sobre a qualidade de lichias 'B3', após a frigoconservação. Os tratamentos foram: T1 = controle (sem pré-resfriamento); T2 = imersão por cinco minutos em água a 2,5°C; T3 = imersão por 10 minutos em água a 2,5°C; T4 = imersão por 20 minutos em água a 2,5°C; T5 = imersão por sete minutos em água a 6°C; T6 = imersão por 20 minutos em água a 8°C e T7 = imersão por 10 minu...
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International Nuclear Information System (INIS)
Eliezer, S.
1982-02-01
In this paper, the physics of laser fusion is described on an elementary level. The irradiated matter consists of a dense inner core surrounded by a less dense plasma corona. The laser radiation is mainly absorbed in the outer periphery of the plasma. The absorbed energy is transported inward to the ablation surface where plasma flow is created. Due to this plasma flow, a sequence of inward going shock waves and heat waves are created, resulting in the compression and heating of the core to high density and temperature. The interaction physics between laser and matter leading to thermonuclear burn is summarized by the following sequence of events: Laser absorption → Energy transport → Compression → Nuclear Fusion. This scenario is shown in particular for a Nd:laser with a wavelength of 1 μm. The wavelength scaling of the physical processes is also discussed. In addition to the laser-plasma physics, the Nd high power pulsed laser is described. We give a very brief description of the oscillator, the amplifiers, the spatial filters, the isolators and the diagnostics involved. Last, but not least, the concept of reactors for laser fusion and the necessary laser system are discussed. (author)
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Directory of Open Access Journals (Sweden)
Li-Ling Chang
2012-05-01
Full Text Available The purpose of the study was to investigate the antioxidant characteristics of <em>Anisomeles indicaem> methanol extract and the inhibitory effect of ovatodiolide on melanogenesis. In the study, the antioxidant capacities of <em>A. indicaem> methanol extract such as DPPH assay, ABTS radical scavenging assay, reducing capacity and metal ion chelating capacity as well as total phenolic content of the extract were investigated. In addition, the inhibitory effects of ovatodiolide on mushroom tyrosinase, B16F10 intracellular tyrosinase and melanin content were determined spectrophotometrically. Our results revealed that the antioxidant capacities of <em>A. indicaem> methanol extract increased in a dose-dependent pattern. The purified ovatodiolide inhibited mushroom tyrosinase activity (IC50 = 0.253 mM, the compound also effectively suppressed intracellular tyrosinase activity (IC50 = 0.469 mM and decreased the amount of melanin (IC50 = 0.435 mM in a dose-dependent manner in B16F10 cells. Our results concluded that <em>A. indicaem> methanol extract displays antioxidant capacities and ovatodiolide purified from the extract inhibited melanogenesis in B16F10 cells. Hence, <em>A. indicaem> methanol extract and ovatodiolide could be applied as a type of dermatological whitening agent in skin care products.
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International Nuclear Information System (INIS)
Yamanaka, Masanobu; Daido, Hiroyuki; Imasaki, Kazuo.
1989-01-01
As the new power lasers which are expected to exert large extending effect to the fields of advanced science and technology including precision engineering as well as laser nuclear fusion, LD-excited solid laser, X-ray laser and free electron laser are taken up and outlined. Recently, the solid laser using high power output, high efficiency semiconductor laser as the exciting beam source has been developed. This is called laser diode (LD)-excited solid laser, and the heightening of power output and efficiency and the extension of life are planned. Its present status and application to medical use, laser machining, laser soldering and so on are described. In 1960, the laser in visible region appeared, however in 1985, the result of observing induced emission beam by electron collision exciting method was reported in USA. In the wavelength range of 200 A, holography and contact X-ray microscope applications were verified. The various types of soft X-ray laser and the perspective hereafter are shown. The principle of free electron laser is explained. In the free electron laser, wavelength can be changed by varying electron beam energy, the period of wiggler magnetic field and the intensity of magnetic field. Further, high efficiency and large power output are possible. Its present status, application and the perspective hereafter are reported. (K.I.)
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DEFF Research Database (Denmark)
Langhelle, Audun; Lossius, Hans Morten; Silfvast, Tom
2004-01-01
exist, however, especially within the ground and air ambulance service, and the EMS systems face several challenges. Main problems and challenges emphasized by the authors are: (1) Denmark: the dispatch centres are presently not under medical control and are without a national criteria based system......Emergency medicine service (EMS) systems in the five Nordic countries have more similarities than differences. One similarity is the involvement of anaesthesiologists as pre-hospital physicians and their strong participation for all critically ill and injured patients in-hospital. Discrepancies do....... Access to on-line medical advice of a physician is not available; (2) Finland: the autonomy of the individual municipalities and their responsibility to cover for primary and specialised health care, as well as the EMS, and the lack of supporting or demanding legislation regarding the EMS; (3) Iceland...
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An application of the theory of laser to nitrogen laser pumped dye laser
International Nuclear Information System (INIS)
Osman, Fatima Ahmed
1998-03-01
In this thesis we gave a general discussion on lasers, reviewing some of their properties, types and application. We also conducted an experiment where we obtained a dye laser pumped by nitrogen laser with a wave length of 337.1 nm and a power of 5 Mw.It was noticed that the produced radiation possesses characteristics different from those of other types of laser. This characteristics determine the tunability i.e the possibility of choosing the appropriately required wave-length of radiation for various applications.(Author)
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Laser propulsion for orbit transfer - Laser technology issues
Horvath, J. C.; Frisbee, R. H.
1985-01-01
Using reasonable near-term mission traffic models (1991-2000 being the assumed operational time of the system) and the most current unclassified laser and laser thruster information available, it was found that space-based laser propulsion orbit transfer vehicles (OTVs) can outperform the aerobraked chemical OTV over a 10-year life-cycle. The conservative traffic models used resulted in an optimum laser power of about 1 MW per laser. This is significantly lower than the power levels considered in other studies. Trip time was taken into account only to the extent that the system was sized to accomplish the mission schedule.
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Efficiencies of laser dyes for atomic vapor laser isotope separation
International Nuclear Information System (INIS)
Maeda, Mitsuo; Oki, Yuji; Uchiumi, Michihiro; Takao, Takayuki; Igarashi, Kaoru; Shimamoto, Kojiro.
1995-01-01
Efficiencies of 30 laser dyes for the atomic vapor laser isotope separation (AVLIS) are experimentally evaluated with a dye laser pumped by a frequency-doubled Nd:YAG laser. On the other hand, a simulation code is developed to describe the laser action of Rhodamine 6G, and the dependence of the laser efficiency on the pump wavelength is calculated. Following conclusions are obtained by these considerations:space: 1) Pyrromethene 567 showed 16% higher laser efficiency than Rhodamine 6G by 532 nm pumping, and Pyrromethene 556 has an ability to provide better efficiency by green light pumping with a Cu vapor laser; 2) Kiton red 620 and Rhodamine 640, whose efficiencies were almost the same as Rhodamine 6G by 532 nm pumping, will show better efficiencies by two-wavelength pumping with a Cu vapor laser. (author)
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Locas al Rescate: The Transnational Hauntings of Queer <em>Cubanidad>
Directory of Open Access Journals (Sweden)
Lázaro Lima
2011-12-01
Full Text Available
“Locas al Rescate: The Transnational Hauntings of Queer <em>Cubanidad>” (originally published in <em>Cuba Transnationalem> offers a significant contribution both to transnational American Studies and to gender studies. In telling the insider story of the alternative identity formation, practices, and forms of “rescue” initiated by the affective activism of the Cuban American society in drag in 1990s Miami/South Beach, Lima resuscitates the liberatory gestures of a subculture defined by its pursuit of its own acceptance, value, and freedom. With their aesthetic and political life on a raft, the gay micro-communities inside Cuban America asserted their own islandic space, Lima observes, performing “takeovers” in and of parks and bars and beaches—creating a post-Habermasian sphere of public activism focused on private parts, saving themselves from AIDS, from the disaffection and disaffiliation of the right-wing Cuban immigrant community, and from the failure of their own yearning to belong, to be wanted, to be embodied as the figure of their compelling <em>Cubanidad>. Against the hegemony of the invented collective politics of the sacrificing immigrants whose recognition of the queer side of being (of a being constituted by identity loss is yet to come, Lima suggests a spectral return—a personal and transnational reckoning of those whose lives the dream of freedom drowned.
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Laser frequency modulator for modulating a laser cavity
Erbert, Gaylen V.
1992-01-01
The present invention relates to a laser frequency modulator for modulating a laser cavity. It is known in the prior art to utilize a PZT (piezoelectric transducer) element in combination with a mirror to change the cavity length of a laser cavity (which changes the laser frequency). Using a PZT element to drive the mirror directly is adequate at frequencies below 10 kHz. However, in high frequency applications (100 kHz and higher) PZT elements alone do not provide a sufficient change in the cavity length. The present invention utilizes an ultrasonic concentrator with a PZT element and mirror to provide modulation of the laser cavity. With an ultrasonic concentrator, the mirror element at the end of a laser cavity can move at larger amplitudes and higher frequencies.
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Directory of Open Access Journals (Sweden)
Caiguo Huang
2012-06-01
Full Text Available A compound named SD118-xanthocillin X (1 (C18H12N2O2, isolated from <em>Penicillium> <em>commune> in a deep-sea sediment sample, has been shown to inhibit the growth of several cancer cell lines <em>in vitroem>. In the present study, we employed a growth inhibition assay and apoptotic analysis to identify the biological effect and detailed mechanism of SD118-xanthocillin X (1 in human hepatocellular carcinoma (HepG2 cells. SD118-xanthocillin X (1 demonstrated a concentration-dependent inhibitory effect on the growth of HepG2 cells and caused slight cellular apoptosis and significantly induced autophagy. Autophagy was detected as early as 12 h by the conversion of microtubule-associated protein 1 light chain 3 (LC3-I to LC3-II, following cleavage and lipid addition to LC3-I. The pharmacological autophagy inhibitor 3-methyladenine largely attenuates the growth inhibition and autophagic effect of SD118-xanthocillin X (1 in HepG2 cells. Our data also indicated that the autophagic effect of SD118-xanthocillin X (1 occurs via the down-regulation of the MEK/ERK signaling pathway and the up-regulated class III PI3K/Beclin 1 signaling pathway.
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Gauger, Robert
1993-01-01
Describes lasers and indicates that learning about laser technology and creating laser technology activities are among the teacher enhancement processes needed to strengthen technology education. (JOW)
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Sorteio de domicílios em favelas em inquéritos por amostragem
Directory of Open Access Journals (Sweden)
Maria Cecilia Goi Porto Alves
2011-12-01
Full Text Available OBJETIVO: Identificar vantagens e desvantagens do uso de segmentos em relação ao sorteio feito a partir da lista completa de endereços, para o sorteio de domicílios em amostragem por conglomerados em múltiplos estágios em favelas. PROCEDIMENTOS METODOLÓGICOS: Estudo qualitativo realizado em quatro favelas sorteadas no Inquérito de Saúde do Município de São Paulo, SP, 2008, nas quais foram aplicadas as duas técnicas. Foram realizados grupos focais com pesquisadores de campo - "arroladores" e entrevistadores do inquérito. Os conteúdos das conversações foram analisados, agrupados em categorias e organizados em núcleos temáticos. ANÁLISE DOS RESULTADOS: A utilização de segmentos de domicílios foi associada a numerosas vantagens e poucas desvantagens. Entre as vantagens, constaram a rapidez e facilidade na elaboração do cadastro de endereços e na localização e identificação de domicílios na etapa de realização das entrevistas, maior segurança dos entrevistadores e da população, maior acesso aos entrevistados, maior estabilidade e maior cobertura do cadastro produzido, e menor ocorrência de erros na identificação dos domicílios sorteados. CONCLUSÕES: A construção de cadastro de domicílios por meio da criação de segmentos é vantajosa em relação à listagem completa de endereços, quando feita em favelas. Por ter se mostrado uma opção econômica e fácil de ser aplicada, constitui alternativa para a simplificação do processo de amostragem em áreas com as suas características de desorganização e adensamento de domicílios.
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ND:GLASS LASER DESIGN FOR LASER ICF FISSION ENERGY (LIFE)
Energy Technology Data Exchange (ETDEWEB)
Caird, J A; Agrawal, V; Bayramian, A; Beach, R; Britten, J; Chen, D; Cross, R; Ebbers, C; Erlandson, A; Feit, M; Freitas, B; Ghosh, C; Haefner, C; Homoelle, D; Ladran, T; Latkowski, J; Molander, W; Murray, J; Rubenchik, S; Schaffers, K; Siders, C W; Stappaerts, E; Sutton, S; Telford, S; Trenholme, J; Barty, C J
2008-10-28
We have developed preliminary conceptual laser system designs for the Laser ICF (Inertial Confinement Fusion) Fission Energy (LIFE) application. Our approach leverages experience in high-energy Nd:glass laser technology developed for the National Ignition Facility (NIF), along with high-energy-class diode-pumped solid-state laser (HEC-DPSSL) technology developed for the DOE's High Average Power Laser (HAPL) Program and embodied in LLNL's Mercury laser system. We present laser system designs suitable for both indirect-drive, hot spot ignition and indirect-drive, fast ignition targets. Main amplifiers for both systems use laser-diode-pumped Nd:glass slabs oriented at Brewster's angle, as in NIF, but the slabs are much thinner to allow for cooling by high-velocity helium gas as in the Mercury laser system. We also describe a plan to mass-produce pump-diode lasers to bring diode costs down to the order of $0.01 per Watt of peak output power, as needed to make the LIFE application economically attractive.
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Directory of Open Access Journals (Sweden)
Yih Yih Kok
2012-04-01
Full Text Available Girinimbine, a carbazole alkaloid isolated from the stem bark of <em>Murraya koenigii em>was tested for the<em> in vitroem> anti-tumour promoting and antioxidant activities. Anti-tumour promoting activity was determined by assaying the capability of this compound to inhibit the expression of early antigen of Epstein-Barr virus (EA-EBV in Raji cells that was induced by the tumour promoter, phorbol 12-myristate 13-acetate. The concentration of this compound that gave an inhibition rate at fifty percent was 6.0 µg/mL and was not cytotoxic to the cells. Immunoblotting analysis of the expression of EA-EBV showed that girinimbine was able to suppress restricted early antigen (EA-R. However, diffused early antigen (EA-D was partially suppressed when used at 32.0 µg/mL. Girinimbine exhibited a very strong antioxidant activity as compared to a-tocopherol and was able to inhibit superoxide generation in the 12-<em>O>-tetradecanoylphorbol-13-acetate (TPA-induced differentiated premyelocytic HL-60 cells more than 95%, when treated with the compound at 5.3 and 26.3 µg/mL, respectively. However girinimbine failed to scavenge the stable diphenyl picryl hydrazyl (DPPH-free radical.
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Directory of Open Access Journals (Sweden)
Yunhuang Yang
2012-06-01
Full Text Available CV_2116 is a small hypothetical protein of 82 amino acids from the Gram-negative coccobacillus <em>Chromobacterium violaceumem>. A PSI-BLAST search using the CV_2116 sequence as a query identified only one hit (E = 2e−07 corresponding to a hypothetical protein OR16_04617 from <em>Cupriavidus basilensisem> OR16, which failed to provide insight into the function of CV_2116. The <em>CV_2116em> gene was cloned into the p15TvLic expression plasmid, transformed into <em>E. coliem>, and 13C- and 15N-labeled NMR samples of CV_2116 were overexpressed in <em>E. coliem> and purified for structure determination using NMR spectroscopy. The resulting high-quality solution NMR structure of CV_2116 revealed a novel α + β fold containing two anti-parallel β -sheets in the <em>N>-terminal two-thirds of the protein and one α-helix in the <em>C>-terminal third of the protein. CV_2116 does not belong to any known protein sequence family and a Dali search indicated that no similar structures exist in the protein data bank. Although no function of CV_2116 could be derived from either sequence or structural similarity searches, the neighboring genes of <em>CV_2116em> encode various proteins annotated as similar to bacteriophage tail assembly proteins. Interestingly, <em>C. violaceumem> exhibits an extensive network of bacteriophage tail-like structures that likely result from lateral gene transfer by incorporation of viral DNA into its genome (prophages due to bacteriophage infection. Indeed, <em>C. violaceumem> has been shown to contain four prophage elements and <em>CV_2116em> resides in the fourth of these elements. Analysis of the putative operon in which CV_2116 resides indicates that CV_2116 might be a component of the bacteriophage tail-like assembly that occurs in <em>C. violaceumem>.
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International Nuclear Information System (INIS)
Lindner, Helmut; Loper, Kristofer H.; Hahn, David W.; Niemax, Kay
2011-01-01
Particles produced by previous laser shots may have significant influence on the analytical signal in laser-induced breakdown spectroscopy (LIBS) and laser ablation inductively coupled plasma (LA-ICP) spectrometry if they remain close to the position of laser sampling. The effects of these particles on the laser-induced breakdown event are demonstrated in several ways. LIBS-experiments were conducted in an ablation cell at atmospheric conditions in argon or air applying a dual-pulse arrangement with orthogonal pre-pulse, i.e., plasma breakdown in a gas generated by a focussed laser beam parallel and close to the sample surface followed by a delayed crossing laser pulse in orthogonal direction which actually ablates material from the sample and produces the LIBS plasma. The optical emission of the LIBS plasma as well as the absorption of the pre-pulse laser was measured. In the presence of particles in the focus of the pre-pulse laser, the plasma breakdown is affected and more energy of the pre-pulse laser is absorbed than without particles. As a result, the analyte line emission from the LIBS plasma of the second laser is enhanced. It is assumed that the enhancement is not only due to an increase of mass ablated by the second laser but also to better atomization and excitation conditions favored by a reduced gas density in the pre-pulse plasma. Higher laser pulse frequencies increase the probability of particle-laser interaction and, therefore, reduce the shot-to-shot line intensity variation as compared to lower particle loadings in the cell. Additional experiments using an aerosol chamber were performed to further quantify the laser absorption by the plasma in dependence on time both with and without the presence of particles. The overall implication of laser-particle interactions for LIBS and LA-ICP-MS/OES are discussed.
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Lindner, Helmut; Loper, Kristofer H.; Hahn, David W.; Niemax, Kay
2011-02-01
Particles produced by previous laser shots may have significant influence on the analytical signal in laser-induced breakdown spectroscopy (LIBS) and laser ablation inductively coupled plasma (LA-ICP) spectrometry if they remain close to the position of laser sampling. The effects of these particles on the laser-induced breakdown event are demonstrated in several ways. LIBS-experiments were conducted in an ablation cell at atmospheric conditions in argon or air applying a dual-pulse arrangement with orthogonal pre-pulse, i.e., plasma breakdown in a gas generated by a focussed laser beam parallel and close to the sample surface followed by a delayed crossing laser pulse in orthogonal direction which actually ablates material from the sample and produces the LIBS plasma. The optical emission of the LIBS plasma as well as the absorption of the pre-pulse laser was measured. In the presence of particles in the focus of the pre-pulse laser, the plasma breakdown is affected and more energy of the pre-pulse laser is absorbed than without particles. As a result, the analyte line emission from the LIBS plasma of the second laser is enhanced. It is assumed that the enhancement is not only due to an increase of mass ablated by the second laser but also to better atomization and excitation conditions favored by a reduced gas density in the pre-pulse plasma. Higher laser pulse frequencies increase the probability of particle-laser interaction and, therefore, reduce the shot-to-shot line intensity variation as compared to lower particle loadings in the cell. Additional experiments using an aerosol chamber were performed to further quantify the laser absorption by the plasma in dependence on time both with and without the presence of particles. The overall implication of laser-particle interactions for LIBS and LA-ICP-MS/OES are discussed.
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Basting, Dirk
2005-01-01
This comprehensive survey on Excimer Lasers investigates the current range of the technology, applications and devices of this commonly used laser source, as well as the future of new technologies, such as F2 laser technology. Additional chapters on optics, devices and laser systems complete this compact handbook. A must read for laser technology students, process application researchers, engineers or anyone interested in excimer laser technology. An effective and understandable introduction to the current and future status of excimer laser technology.
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Laser systems for on-line laser ion sources
International Nuclear Information System (INIS)
Geppert, Christopher
2008-01-01
Since its initiation in the middle of the 1980s, the resonant ionization laser ion source has been established as a reliable and efficient on-line ion source for radioactive ion beams. In comparison to other on-line ion sources it comprises the advantages of high versatility for the elements to be ionized and of high selectivity and purity for the ion beam generated by resonant laser radiation. Dye laser systems have been the predominant and pioneering working horses for laser ion source applications up to recently, but the development of all-solid-state titanium:sapphire laser systems has nowadays initiated a significant evolution within this field. In this paper an overview of the ongoing developments will be given, which have contributed to the establishment of a number of new laser ion source facilities worldwide during the last five years.
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Directory of Open Access Journals (Sweden)
Minying Sun
2012-04-01
Full Text Available Exposure to endogenous sex hormones has been reported as a risk factor for breast cancer. The <em>CYP11A1em> gene encodes the key enzyme that catalyzes the initial and rate-limiting step in steroid hormone synthesis. In this study, the associations between single nucleotide polymorphisms (SNPs in <em>CYP11A1em> and breast cancer susceptibility were examined. Six SNPs in <em>CYP11A1 em>were genotyped using the MassARRAY IPLEX platform in 530 breast cancer patients and 546 healthy controls. Association analyses based on a χ2 test and binary logistic regression were performed to determine the odds ratio (<em>OR> and 95% confidence interval (95% <em>CI> for each SNP. Two loci (rs2959008 and rs2279357 showed evidence of associations with breast cancer risk. The variant genotype C/T-C/C of rs2959008 was significantly associated with a decreased risk (age-adjusted<em> ORem>, 0.75; 95% <em>CI>, 0.58–0.96; <em>P em>= 0.023 compared with the wild-type TT. However, the homozygous TT variant of rs2279357 exhibited increased susceptibility to breast cancer (age-adjusted<em> ORem>, 1.44; 95% <em>CI>, 1.05–1.98; <em>P em>= 0.022. The locus rs2959003 also showed an appreciable effect, but no associations were observed for three other SNPs. Our results suggest that polymorphisms of <em>CYP11A1em> are related to breast cancer susceptibility in Han Chinese women of South China.
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Histologic evaluation of laser lipolysis: pulsed 1064-nm Nd:YAG laser versus cw 980-nm diode laser.
Mordon, Serge; Eymard-Maurin, Anne Françoise; Wassmer, Benjamin; Ringot, Jean
2007-01-01
The use of the laser as an auxiliary tool has refined the traditional technique for lipoplasty. During laser lipolysis, the interaction between the laser and the fat produced direct cellular destruction before the suction, reduced bleeding, and promoted skin tightening. This study sought to perform a comparative histologic evaluation of laser lipolysis with the pulsed 1064-nm Nd:YAG laser versus a continuous 980-nm diode laser. A pulsed 1064-nm Nd:YAG (Smart-Lipo; Deka, Italy) and a CW 980-nm diode laser (Pharaon, Osyris, France) were evaluated at different energy settings for lipolysis on the thighs of a fresh cadaver. The lasers were coupled to a 600-microm optical fiber inserted in a 1-mm diameter cannula. Biopsy specimens were taken on irradiated and non-irradiated areas. Hematoxylin-erythrosin-safran staining and immunostaining (anti-PS100 polyclonal antibody) were performed to identify fat tissue damage. In the absence of laser exposures (control specimens), cavities created by cannulation were seen; adipocytes were round in appearance and not deflated. At low energy settings, tumescent adipocytes were observed. At higher energy settings, cytoplasmic retraction, disruption of membranes, and heat-coagulated collagen fibers were noted; coagulated blood cells were also present. For the highest energy settings, carbonization of fat tissue involving fibers and membranes was clearly seen. For equivalent energy settings, 1064-nm and 980-nm wavelengths gave similar histologic results. Laser lipolysis is a relatively new technique that is still under development. Our histologic findings suggest several positive benefits of the laser, including skin retraction and a reduction in intraoperative bleeding. The interaction of the laser with the tissue is similar at 980 nm and 1064 nm with the same energy settings. Because higher volumes of fat are removed with higher total energy, a high-power 980-nm diode laser could offer an interesting alternative to the 1064-nm Nd
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Tapered diode laser pumped 946 nm Nd:YAG laser
DEFF Research Database (Denmark)
Cheng, Haynes Pak Hay; Jensen, Ole Bjarlin; Petersen, Paul Michael
2009-01-01
We successfully implemented a 946 nm Nd:YAG laser based on a 808 nm tapered diode pump laser. The tapered diode is developed at the Ferdinand-Braun-Institute fur Hochstfrequenztechnik in Germany. Figure 2 shows the experimental setup and results of each pump source coupled into a 1.5 mm crystal...... laser, we show that tapered diode laser pumping potentially increase the power of 946 nm lasers by a factor of two and reduce the threshold by a factor of three....
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Directory of Open Access Journals (Sweden)
Josef Jampilek
2012-08-01
Full Text Available A series of twenty-five novel salicylanilide <em>N>-alkylcarbamates were investigated as potential acetylcholinesterase inhibitors. The compounds were tested for their ability to inhibit acetylcholinesterase (AChE from electric eel (<em>Electrophorus electricusem> L.. Experimental lipophilicity was determined, and the structure-activity relationships are discussed. The mode of binding in the active site of AChE was investigated by molecular docking. All the discussed compounds expressed significantly higher AChE inhibitory activity than rivastigmine and slightly lower than galanthamine. Disubstitution by chlorine in C'(3,4 of the aniline ring and the optimal length of hexyl-undecyl alkyl chains in the carbamate moiety provided the most active AChE inhibitors. Monochlorination in C'(4 exhibited slightly more effective AChE inhibitors than in C'(3. Generally it can be stated that compounds with higher lipophilicity showed higher inhibition, and the activity of the compounds is strongly dependent on the length of the <em>N>-alkyl chain.
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Directory of Open Access Journals (Sweden)
Tomomi Morimoto
2012-06-01
Full Text Available Chronic bee paralysis virus (CBPV infection causes chronic paralysis and loss of workers in honey bee colonies around the world. Although CBPV shows a worldwide distribution, it had not been molecularly detected in Japan. Our investigation of <em>Apis melliferaem> and <em>Apis cerana japonicaem> colonies with RT-PCR has revealed CBPV infection in <em>A. melliferaem> but not <em>A. c. japonicaem> colonies in Japan. The prevalence of CBPV is low compared with that of other viruses: deformed wing virus (DWV, black queen cell virus (BQCV, Israel acute paralysis virus (IAPV, and sac brood virus (SBV, previously reported in Japan. Because of its low prevalence (5.6% in <em>A. melliferaem> colonies, the incidence of colony losses by CBPV infection must be sporadic in Japan. The presence of the (− strand RNA in dying workers suggests that CBPV infection and replication may contribute to their symptoms. Phylogenetic analysis demonstrates a geographic separation of Japanese isolates from European, Uruguayan, and mainland US isolates. The lack of major exchange of honey bees between Europe/mainland US and Japan for the recent 26 years (1985–2010 may have resulted in the geographic separation of Japanese CBPV isolates.
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Emergency Medical Service (EMS) Stations
Kansas Data Access and Support Center — EMS Locations in Kansas The EMS stations dataset consists of any location where emergency medical services (EMS) personnel are stationed or based out of, or where...
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Chatwin, Chris; Young, Rupert; Birch, Philip
2015-01-01
Some laser history;\\ud Airborne Laser Testbed & Chemical Oxygen Iodine Laser (COIL);\\ud Laser modes and beam propagation;\\ud Fibre lasers and applications;\\ud US Navy Laser system – NRL 33kW fibre laser;\\ud Lockheed Martin 30kW fibre laser;\\ud Conclusions
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Spectroscopic and imaging diagnostics of pulsed laser deposition laser plasmas
International Nuclear Information System (INIS)
Thareja, Raj K.
2002-01-01
An overview of laser spectroscopic techniques used in the diagnostics of laser ablated plumes used for thin film deposition is given. An emerging laser spectroscopic imaging technique for the laser ablation material processing is discussed. (author)
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Laser-diode pumped 40-W Yb:YAG ceramic laser.
Hao, Qiang; Li, Wenxue; Pan, Haifeng; Zhang, Xiaoyi; Jiang, Benxue; Pan, Yubai; Zeng, Heping
2009-09-28
We demonstrated a high-power continuous-wave (CW) polycrystalline Yb:YAG ceramic laser pumped by fiber-pigtailed laser diode at 968 nm with 400 mum fiber core. The Yb:YAG ceramic laser performance was compared for different Yb(3+) ion concentrations in the ceramics by using a conventional end-pump laser cavity consisting of two flat mirrors with output couplers of different transmissions. A CW laser output of 40 W average power with M(2) factor of 5.8 was obtained with 5 mol% Yb concentration under 120 W incident pump power. This is to the best of our knowledge the highest output power in end-pumped bulk Yb:YAG ceramic laser.
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Directory of Open Access Journals (Sweden)
Guillermo Villalobos
2012-02-01
Full Text Available Ceramic laser materials have come a long way since the first demonstration of lasing in 1964. Improvements in powder synthesis and ceramic sintering as well as novel ideas have led to notable achievements. These include the first Nd:yttrium aluminum garnet (YAG ceramic laser in 1995, breaking the 1 KW mark in 2002 and then the remarkable demonstration of more than 100 KW output power from a YAG ceramic laser system in 2009. Additional developments have included highly doped microchip lasers, ultrashort pulse lasers, novel materials such as sesquioxides, fluoride ceramic lasers, selenide ceramic lasers in the 2 to 3 μm region, composite ceramic lasers for better thermal management, and single crystal lasers derived from polycrystalline ceramics. This paper highlights some of these notable achievements.
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International Nuclear Information System (INIS)
Cantrell, C.D.; Carbone, R.J.
1977-01-01
An infrared laser system and method for isotope separation may comprise a molecular gas laser oscillator to produce a laser beam at a first wavelength, Raman spin flip means for shifting the laser to a second wavelength, a molecular gas laser amplifier to amplify said second wavelength laser beam to high power, and optical means for directing the second wavelength, high power laser beam against a desired isotope for selective excitation thereof in a mixture with other isotopes. The optical means may include a medium which shifts the second wavelength high power laser beam to a third wavelength, high power laser beam at a wavelength coincidental with a corresponding vibrational state of said isotope and which is different from vibrational states of other isotopes in the gas mixture
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Sanghera, Jasbinder; Kim, Woohong; Villalobos, Guillermo; Shaw, Brandon; Baker, Colin; Frantz, Jesse; Sadowski, Bryan; Aggarwal, Ishwar
2012-01-01
Ceramic laser materials have come a long way since the first demonstration of lasing in 1964. Improvements in powder synthesis and ceramic sintering as well as novel ideas have led to notable achievements. These include the first Nd:yttrium aluminum garnet (YAG) ceramic laser in 1995, breaking the 1 KW mark in 2002 and then the remarkable demonstration of more than 100 KW output power from a YAG ceramic laser system in 2009. Additional developments have included highly doped microchip lasers, ultrashort pulse lasers, novel materials such as sesquioxides, fluoride ceramic lasers, selenide ceramic lasers in the 2 to 3 μm region, composite ceramic lasers for better thermal management, and single crystal lasers derived from polycrystalline ceramics. This paper highlights some of these notable achievements. PMID:28817044
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Directory of Open Access Journals (Sweden)
Waldo Lino Júnior
2005-01-01
Full Text Available Os autores estudaram os efeitos do laser Hólmio:Ítrio-Alumínio-Granada (Ho: YAG sobre as dimensões do tendão (comprimento e largura proximal e distal e sobre a celularidade e arranjo das fibras de colágeno em 20 ratos adultos, machos, brancos (Ratus Novergicus da varidade Wistar. Os animais foram divididos em dois grupos de acordo com o tempo de seguimento (12 e 24 semanas e de acordo com a forma de aplicação do laser (contínua e em dois pontos. Utilizou-se aparelho de laser de Hólmio (pulsátil, estado sólido, com ondas de 2,1 microns, com potência de 40 watts, ponteira OmniTip de 30º . Após o sacrifício, foram comparadas por meio de testes não paramétricos (considerando p = 0,05 as medidas de comprimento e da largura (proximal e distal dos tendões do lado operado e do lado não operado. A medida do comprimento do lado operado foi significativamente maior nos dois grupos de seguimento, quando comparado com o lado não operado, porém, não houve diferença significativa dessas medidas em função do tipo de aplicação do laser. Do mesmo modo, a medida da largura, tanto na região proximal quanto distal, foram significativamente maiores no lado operado nos dois grupos de seguimento, sem apresentar diferença significativa em função do tipo de aplicação. Quando se compararam as medidas nos dois grupos de seguimento, o comprimento e a largura distal tenderam a ser maiores após 24 semanas, enquanto que a largura, na região proximal, foi significativamente maior nesse grupo. Quanto à avaliação microscópica subjetiva, tanto nos cortes longitudinais como transversais, pôde-se verificar aumento do número de fibroblastos, principalmente no grupo de 12 semanas. A concentração média de fibroblastos nos tendões com 24 semanas de seguimento foi considerada como intermediário entre o grupo de 12 semanas e os tendões não operados. Na região entre os fascículos, o tecido conjuntivo era exuberante no grupo com 12 semanas
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Laser cutting: industrial relevance, process optimization, and laser safety
Haferkamp, Heinz; Goede, Martin; von Busse, Alexander; Thuerk, Oliver
1998-09-01
Compared to other technological relevant laser machining processes, up to now laser cutting is the application most frequently used. With respect to the large amount of possible fields of application and the variety of different materials that can be machined, this technology has reached a stable position within the world market of material processing. Reachable machining quality for laser beam cutting is influenced by various laser and process parameters. Process integrated quality techniques have to be applied to ensure high-quality products and a cost effective use of the laser manufacturing plant. Therefore, rugged and versatile online process monitoring techniques at an affordable price would be desirable. Methods for the characterization of single plant components (e.g. laser source and optical path) have to be substituted by an omnivalent control system, capable of process data acquisition and analysis as well as the automatic adaptation of machining and laser parameters to changes in process and ambient conditions. At the Laser Zentrum Hannover eV, locally highly resolved thermographic measurements of the temperature distribution within the processing zone using cost effective measuring devices are performed. Characteristic values for cutting quality and plunge control as well as for the optimization of the surface roughness at the cutting edges can be deducted from the spatial distribution of the temperature field and the measured temperature gradients. Main influencing parameters on the temperature characteristic within the cutting zone are the laser beam intensity and pulse duration in pulse operation mode. For continuous operation mode, the temperature distribution is mainly determined by the laser output power related to the cutting velocity. With higher cutting velocities temperatures at the cutting front increase, reaching their maximum at the optimum cutting velocity. Here absorption of the incident laser radiation is drastically increased due to
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Consumo de energia em escalonadores de transações em sistemas de memória transacional em software
Marques Junior, Ademir [UNESP
2016-01-01
O conceito de Memória Transacional foi criado para simplificar a sincronização de dados em memória, necessária para evitar a computação de dados inconsistentes por processadores multinúcleos, que se tornaram padrão devido às limitações encontradas em processadores de um núcleo. Em evolução constante pela busca de desempenho, os escalonadores de transação foram criados como alternativa aos gerenciadores de contenção presentes nos Sistemas de Memória Transacional. O consumo de energia é preocup...
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Laser wakefield acceleration with high-power, few-cycle mid-IR lasers
Papp, Daniel; Wood, Jonathan C.; Gruson, Vincent; Bionta, Mina; Gruse, Jan-Niclas; Cormier, Eric; Najmudin, Zulfikar; Légaré, François; Kamperidis, Christos
2018-01-01
The study of laser wakefield electron acceleration (LWFA) using mid-IR laser drivers is a promising path for future laser driven electronaccelerators, when compared to traditional near-IR laser drivers uperating at 0.8-1 {\\mu}m central wavelength ({\\lambda}laser), as the necessary vector potential a_0 for electron injection can be achieved with smaller laser powers due to the linear dependence on {\\lambda}laser. In this work, we perform 2D PIC simulations on LWFA using few-cycle high power (5...
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Laser requirements for a laser fusion energy power plant
Institute of Scientific and Technical Information of China (English)
Stephen; E.Bodner; Andrew; J.Schmitt; John; D.Sethian
2013-01-01
We will review some of the requirements for a laser that would be used with a laser fusion energy power plant, including frequency, spatial beam smoothing, bandwidth, temporal pulse shaping, efficiency, repetition rate, and reliability. The lowest risk and optimum approach uses a krypton fluoride gas laser. A diode-pumped solid-state laser is a possible contender.
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Energy Technology Data Exchange (ETDEWEB)
Dr. Alan Chodos; Elizabeth A. Rogan
2011-08-25
LaserFest was the yearlong celebration, during 2010, of the 50th anniversary of the demonstration of the first working laser. The goals of LaserFest were: to highlight the impact of the laser in its manifold commercial, industrial and medical applications, and as a tool for ongoing scientific research; to use the laser as one example that illustrates, more generally, the route from scientific innovation to technological application; to use the laser as a vehicle for outreach, to stimulate interest among students and the public in aspects of physical science; to recognize and honor the pioneers who developed the laser and its many applications; to increase awareness among policymakers of the importance of R&D funding as evidenced by such technology as lasers. One way in which LaserFest sought to meet its goals was to encourage relevant activities at a local level all across the country -- and also abroad -- that would be identified with the larger purposes of the celebration and would carry the LaserFest name. Organizers were encouraged to record and advertise these events through a continually updated web-based calendar. Four projects were explicitly detailed in the proposals: 1) LaserFest on the Road; 2) Videos; 3) Educational material; and 4) Laser Days.
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Development of high-power CO2 lasers and laser material processing
Nath, Ashish K.; Choudhary, Praveen; Kumar, Manoj; Kaul, R.
2000-02-01
Scaling laws to determine the physical dimensions of the active medium and optical resonator parameters for designing convective cooled CO2 lasers have been established. High power CW CO2 lasers upto 5 kW output power and a high repetition rate TEA CO2 laser of 500 Hz and 500 W average power incorporated with a novel scheme for uniform UV pre- ionization have been developed for material processing applications. Technical viability of laser processing of several engineering components, for example laser surface hardening of fine teeth of files, laser welding of martensitic steel shroud and titanium alloy under-strap of turbine, laser cladding of Ni super-alloy with stellite for refurbishing turbine blades were established using these lasers. Laser alloying of pre-placed SiC coating on different types of aluminum alloy, commercially pure titanium and Ti-6Al-4V alloy, and laser curing of thermosetting powder coating have been also studied. Development of these lasers and results of some of the processing studies are briefly presented here.
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Estratégia e estrutura: em busca do alinhamento organizacional em um clube social esportivo
Cruz Junior,Augusto de Toledo; Carvalho,Marly Monteiro de; Laurindo,Fernando José Barbin
2005-01-01
A literatura descreve tipologias de formas organizações, que podem ser divididas em organização baseada em trabalho e organização baseada em conhecimento. A forma de representação mais utilizada é o organograma. Contudo, esta forma de representação não consegue ilustrar adequadamente a dinâmica de funcionamento da organização, sobretudo em organizações em que o conhecimento e a experiência são os ativos-chave. Com o objetivo de investigar o processo de alinhamento entre estratégia e estrutura...
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Laser plasma instability experiments with KrF lasers
International Nuclear Information System (INIS)
Weaver, J. L.; Karasik, M.; Serlin, V.; Obenschain, S.; Chan, L-Y.; Kehne, D.; Schmitt, A. J.; Colombant, D.; Velikovich, A.; Oh, J.; Lehmberg, R. H.; Afeyan, B.; Phillips, L.; Seely, J.; Brown, C.; Feldman, U.; Aglitskiy, Y.; Mostovych, A. N.; Holland, G.
2007-01-01
Deleterious effects of laser-plasma instability (LPI) may limit the maximum laser irradiation that can be used for inertial confinement fusion. The short wavelength (248 nm), large bandwidth, and very uniform illumination available with krypton-fluoride (KrF) lasers should increase the maximum usable intensity by suppressing LPI. The concomitant increase in ablation pressure would allow implosion of low-aspect-ratio pellets to ignition with substantial gain (>20) at much reduced laser energy. The proposed KrF-laser-based Fusion Test Facility (FTF) would exploit this strategy to achieve significant fusion power (150 MW) with a rep-rate system that has a per pulse laser energy well below 1 MJ. Measurements of LPI using the Nike KrF laser are presented at and above intensities needed for the FTF (I∼2x10 15 W/cm 2 ). The results to date indicate that LPI is indeed suppressed. With overlapped beam intensity above the planar, single beam intensity threshold for the two-plasmon decay instability, no evidence of instability was observed via measurements of (3/2)ω o and (1/2)ω o harmonic emissions
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DEFF Research Database (Denmark)
Johansen, Tom Keinicke; Kazmierski, Christophe; Jany, Christophe
2007-01-01
In this paper three options for very-high bit rate integrated electro-absorption modulated laser (EML) structures are investigated using electromagnetic simulation. A physics based distributed equivalent circuit model taking the slowwave propagation characteristics of the modulation signal...... into account is proposed for the electro-absorption modulator (EAM)electrode arrangement. This model makes it possible to apply an EM/circuit co-simulation approach to estimate the electrical to optical transmission bandwidth for the integrated EML. It is shown that a transmission bandwidth of 70 GHz seems...
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Physics of laser fusion. Volume III. High-power pulsed lasers
International Nuclear Information System (INIS)
Holzrichter, J.F.; Eimerl, D.; George, E.V.; Trenholme, J.B.; Simmons, W.W.; Hunt, J.T.
1982-09-01
High-power pulsed lasers can deliver sufficient energy on inertial-confinement fusion (ICF) time scales (0.1 to 10 ns) to heat and compress deuterium-tritium fuel to fusion-reaction conditions. Several laser systems have been examined, including Nd:glass, CO 2 , KrF, and I 2 , for their ICF applicability. A great deal of developmental effort has been applied to the Nd:glass laser and the CO 2 gas laser systems; these systems now deliver > 10 4 J and 20 x 10 12 W to ICF targets. We are constructing the Nova Nd:glass laser at LLNL to provide > 100 kJ and > 100 x 10 12 W of 1-μm radiation for fusion experimentation in the mid-1980s. For ICF target gain > 100 times the laser input, we expect that the laser driver must deliver approx. 3 to 5 MJ of energy on a time scale of 10 to 20 ns. In this paper we review the technological status of fusion-laser systems and outline approaches to constructing high-power pulsed laser drivers
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Directory of Open Access Journals (Sweden)
Yu-Zhou Du
2012-08-01
Full Text Available The complete 15,413-bp mitochondrial genome (mitogenome of <em>Sesamia inferensem> (Walker (Lepidoptera: Noctuidae was sequenced and compared with those of four other noctuid moths. All of the mitogenomes analyzed displayed similar characteristics with respect to gene content, genome organization, nucleotide comparison, and codon usages. Twelve-one protein-coding genes (PCGs utilized the standard ATN, but the <em>cox1 em>gene used CGA as the initiation codon; <em>cox1em>, <em>cox2em>, and <em>nad4em> genes had the truncated termination codon T in the <em>S. inferens em>mitogenome. All of the tRNA genes had typical cloverleaf secondary structures except for <em>trnS1(AGNem>, in which the dihydrouridine (DHU arm did not form a stable stem-loop structure. Both the secondary structures of <em>rrnL> and <em>rrnS> genes inferred from the <em>S. inferens em>mitogenome closely resembled those of other noctuid moths. In the A+T-rich region, the conserved motif “ATAGA” followed by a long T-stretch was observed in all noctuid moths, but other specific tandem-repeat elements were more variable. Additionally, the <em>S. inferens em>mitogenome contained a potential stem-loop structure, a duplicated 17-bp repeat element, a decuplicated segment, and a microsatellite “(AT7”, without a poly-A element upstream of the<em> trnM em>in the A+T-rich region. Finally, the phylogenetic relationships were reconstructed based on amino acid sequences of mitochondrial 13 PCGs, which support the traditional morphologically based view of relationships within the Noctuidae.
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Energy Technology Data Exchange (ETDEWEB)
Strefezza, Claudia
2001-07-01
Previous in vitro studies have demonstrated that Ho:YLF laser is capable of inducing physical and chemical changes on dental surfaces treated for caries prevention. The temperature in the pulp chamber was in vitro evaluated to as a function of the power and frequency of the laser irradiation. The purpose of this work is to verify the occurrence of pulp inflammation after Ho:YLF laser irradiation using different parameters in rabbits' teeth. The premolars and molars of ten rabbits (NZB) were divided in two groups according to the irradiation energy values of a Ho:YLF laser prototype operating at 2.065{mu}m wave length, frequency of O,5Hz and pulse length of 250{mu}s. An group A teeth were irradiated with using ten pulses of 334mJ/pulse of a Ho:YLF laser prototype operating at O.5Hz, and group B, with 512mJ/pulse. Animals were killed by transcardiac perfusion and the samples were prepared for histopathological analysis. The in vitro temperature monitoring revealed an increase of 1 deg C for the 334mJ/pulse energy and 4.5 deg C for the 512mJ/pulse energy. SEM observations showed the occurrence of melting and resolidification in dental surface. From the in vivo analysis it can be concluded that both employed laser parameters did not induce to any inflammatory response from the pulp. (author)
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Energy Technology Data Exchange (ETDEWEB)
Strefezza, Claudia
2001-07-01
Previous in vitro studies have demonstrated that Ho:YLF laser is capable of inducing physical and chemical changes on dental surfaces treated for caries prevention. The temperature in the pulp chamber was in vitro evaluated to as a function of the power and frequency of the laser irradiation. The purpose of this work is to verify the occurrence of pulp inflammation after Ho:YLF laser irradiation using different parameters in rabbits' teeth. The premolars and molars of ten rabbits (NZB) were divided in two groups according to the irradiation energy values of a Ho:YLF laser prototype operating at 2.065{mu}m wave length, frequency of O,5Hz and pulse length of 250{mu}s. An group A teeth were irradiated with using ten pulses of 334mJ/pulse of a Ho:YLF laser prototype operating at O.5Hz, and group B, with 512mJ/pulse. Animals were killed by transcardiac perfusion and the samples were prepared for histopathological analysis. The in vitro temperature monitoring revealed an increase of 1 deg C for the 334mJ/pulse energy and 4.5 deg C for the 512mJ/pulse energy. SEM observations showed the occurrence of melting and resolidification in dental surface. From the in vivo analysis it can be concluded that both employed laser parameters did not induce to any inflammatory response from the pulp. (author)
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Directory of Open Access Journals (Sweden)
Giles E. Budge
2012-08-01
Full Text Available The Small hive beetle, <em>Aethina tumidaem>, is an invasive pest of honey bees. Indigenous to sub-Saharan Africa, it has now become established in North America and Australia. It represents a serious threat to European honey bees. Commercially available entomopathogenic agents were screened for their potential to control beetle larvae. Entomopathogenic fungi investigated had minimal impact. The nematodes <em>Steinernema
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2017-01-01
This book serves as a comprehensive, up-to-date reference about this cutting-edge laser technology and its many new and interesting developments. Various aspects and trends of Raman fiber lasers are described in detail by experts in their fields. Raman fiber lasers have progressed quickly in the past decade, and have emerged as a versatile laser technology for generating high power light sources covering a spectral range from visible to mid-infrared. The technology is already being applied in the fields of telecommunication, astronomy, cold atom physics, laser spectroscopy, environmental sensing, and laser medicine. This book covers various topics relating to Raman fiber laser research, including power scaling, cladding and diode pumping, cascade Raman shifting, single frequency operation and power amplification, mid-infrared laser generation, specialty optical fibers, and random distributed feedback Raman fiber lasers. The book will appeal to scientists, students, and technicians seeking to understand the re...
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Effect of laser spot size on energy balance in laser induced plasmas
International Nuclear Information System (INIS)
Pant, H.C.; Sharma, S.; Bhawalkar, D.D.
1980-01-01
The effect of the laser spot size on laser light absorption in laser induced plasmas from solid targets was studied. It was found that at a constant laser intensity on the target, reduction in the laser spot size enhances the net laser energy absorption. It was also observed that the laser light reflection from the target becomes more diffused when the focal spot size is reduced
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Co-Autoria em Ensino e Pesquisa em Administração e Contabilidade no Brasil: Uma Década em Análise
Directory of Open Access Journals (Sweden)
Lélis Balestrin Espartel
2011-12-01
Full Text Available Uma das principais tendências verificadas nos últimos anos é o aumento da colaboração científica, caracterizada pela co-autoria. Muitos autores destacam a importância do tema e indicam o crescimento da co-autoria na produção acadêmica. Entretanto, em âmbito nacional, nenhum trabalho considerou a análise de co-autoria no campo da Administração. Com base nisso, este estudo, de caráter bibliométrico, analisou os artigos publicados em co-autoria nos anais dos congressos promovidos pela ANPAD no período entre 2001 e 2010, perfazendo 12 eventos: 10 Encontros da ANPAD (EnANPAD e 2 Encontros de Ensino e Pesquisa em Administração e Contabilidade (EnEPQ. Ao total foram investigados 778 trabalhos. De uma forma geral, nota-se que grande parte dos trabalhos conduzidos em Administração no Brasil, na última década, utiliza a co-autoria. Quanto ao formato dos artigos, observa-se que a co-autoria prevalece nos estudos empíricos, enquanto os estudos teóricos são desenvolvidos, em sua maioria, por um único autor. No caso dos trabalhos teóricos, elaborados em co-autoria, nota-se, em média, um número menor de autores do que em trabalhos empíricos. Dentre os empíricos realizados em co-autoria, também há diferenças significativas, sendo que os trabalhos quantitativos apresentaram uma média de autores superior a dos artigos qualitativos. Também foi realizada uma análise da rede formada pelas 197 IES identificadas, fazendo considerações sobre a sua densidade, distância geodésica média, centralização e proximidade entre os elos. Acrescido a estas análises, discussões e considerações a respeito da co-autoria em Administração também são apresentadas no artigo. Sugestões de pesquisas futuras são propostas.
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Influence of laser parameters on laser ultrasonic efficiency
CSIR Research Space (South Africa)
Forbes, A
2007-01-01
Full Text Available , TEA CO2 lasers, laser chemistry, short pulses 1. INTRODUCTION Polymer-matrix composites are increasingly used in the aerospace industry, particularly in the manufacture of modern fighter planes1-3. The number and complexity of such composites... efficiency can be improved by utilising short pulses in the 3–4 µm and 10 µm spectral regions1. Short pulse 10 µm radiation can be produced by transversely excited, atmospheric CO2 (TEA CO2) lasers. Due to the technological maturity of these lasers...
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Directory of Open Access Journals (Sweden)
Farid Shokry Ataya
2012-08-01
Full Text Available Acid lipase belongs to a family of enzymes that is mainly present in lysosomes of different organs and the stomach. It is characterized by its capacity to withstand acidic conditions while maintaining high lipolytic activity. We cloned for the first time the full coding sequence of camel’s lysosomal acid lipase, <em>cLIPA em>using RT-PCR technique (Genbank accession numbers JF803951 and AEG75815, for the nucleotide and aminoacid sequences respectively. The cDNA sequencing revealed an open reading frame of 1,197 nucleotides that encodes a protein of 399 aminoacids which was similar to that from<em> em>other related mammalian species. Bioinformatic analysis was used to determine the aminoacid sequence, 3D structure and phylogeny of cLIPA. Bioinformatics analysis suggested the molecular weight of the translated protein to be 45.57 kDa, which could be decreased to 43.16 kDa after the removal of a signal peptide comprising the first 21 aminoacids. The deduced <em>cLIPA em>sequences exhibited high identity with <em>Equus caballus em>(86%, <em>Numascus leucogenysem> (85%, <em>Homo sapiensem> (84%,<em> Sus scrofaem> (84%, <em>Bos taurus em>(82% and <em>Ovis aries em>(81%. cLIPA shows high aminoacid sequence identity with human and dog-gastric lipases (58%, and 59% respectively which makes it relevant to build a 3D structure model for cLIPA. The comparison confirms the presence of the catalytic triad and the oxyanion hole in cLIPA. Phylogenetic analysis revealed that camel <em>cLIPA em>is grouped with monkey, human, pig, cow and goat. The level of expression of <em>cLIPA em>in five camel tissues was examined using Real Time-PCR. The highest level of <em>cLIPA em>transcript was found in the camel testis (162%, followed by spleen (129%, liver (100%, kidney (20.5% and lung (17.4%.
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Energy Technology Data Exchange (ETDEWEB)
Tavares, Henrique Dutra Simoes
2001-07-01
Microleakage at the interface between the teeth and the restorative materials remains a problem with composite resin restorations. Microleakage at the gingival margins of class V cavities restorations still challenge as they are usually placed in dentin and/or cementum. Previous studies have shown that the cavity preparation with Er:YAG laser is possible. It has been reported that Er:YAG laser has ability to create irregular surface providing micromechanical retention for adhesive dental restorative materials and to improve marginal sealing. The purpose of this in vitro study was to evaluate the marginal microleakage on class V cavities prepared with Er:YAG laser and etched with acid or with Er:YAG laser and acid, in compared to those prepared and etched conventionally. Thirty human molars were divided into three groups, namely: group I - prepared with Er:YAG laser (KaVo KEY Laser II - Germany) and etched with 37% phosphoric acid; group II - prepared with Er:YAG laser and etched with Er:YAG laser and 37% phosphoric acid; group III (control group) - prepared with high speed drill and etched with 37% phosphoric acid. All cavities were treated with same adhesive system (Single Bond - 3M) and restored with the composite resin (Z100 - 3M), according to the manufacturer's instructions. The specimens were stored at 37 deg C in water for 24 hours, polished with Sof-Lex discs (3M), thermally stressed, sealed with a nail polish coating except for the area of the restoration and 1 mm around it, and immersed in a 50% aqueous solution of silver nitrate for 24 hours. After that, the specimens were rinsed in water, soaked in a photodeveloping solution and exposed to a fluorescent light for 8 hours. The teeth were embedded in an autopolymerizing resin and sectioned longitudinally using a diamond saw microtome under running water. The sections were photographed. The microleakage at the occlusal cavity and at the gingival margins of each specimen was evaluated with scores (0-3) by
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Energy Technology Data Exchange (ETDEWEB)
Tavares, Henrique Dutra Simoes
2001-07-01
Microleakage at the interface between the teeth and the restorative materials remains a problem with composite resin restorations. Microleakage at the gingival margins of class V cavities restorations still challenge as they are usually placed in dentin and/or cementum. Previous studies have shown that the cavity preparation with Er:YAG laser is possible. It has been reported that Er:YAG laser has ability to create irregular surface providing micromechanical retention for adhesive dental restorative materials and to improve marginal sealing. The purpose of this in vitro study was to evaluate the marginal microleakage on class V cavities prepared with Er:YAG laser and etched with acid or with Er:YAG laser and acid, in compared to those prepared and etched conventionally. Thirty human molars were divided into three groups, namely: group I - prepared with Er:YAG laser (KaVo KEY Laser II - Germany) and etched with 37% phosphoric acid; group II - prepared with Er:YAG laser and etched with Er:YAG laser and 37% phosphoric acid; group III (control group) - prepared with high speed drill and etched with 37% phosphoric acid. All cavities were treated with same adhesive system (Single Bond - 3M) and restored with the composite resin (Z100 - 3M), according to the manufacturer's instructions. The specimens were stored at 37 deg C in water for 24 hours, polished with Sof-Lex discs (3M), thermally stressed, sealed with a nail polish coating except for the area of the restoration and 1 mm around it, and immersed in a 50% aqueous solution of silver nitrate for 24 hours. After that, the specimens were rinsed in water, soaked in a photodeveloping solution and exposed to a fluorescent light for 8 hours. The teeth were embedded in an autopolymerizing resin and sectioned longitudinally using a diamond saw microtome under running water. The sections were photographed. The microleakage at the occlusal cavity and at the gingival margins of each specimen was evaluated with scores (0
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Improving the laser brightness of a commercial laser system
Naidoo, Darryl; Litvin, Igor; Forbes, Andrew
2016-02-01
We investigate the selection of a flat-top beam and a Gaussian beam inside a laser cavity on opposing mirrors. The concept is tested external to the laser cavity in a single pass and double pass regime where the latter mimics a single round trip in the laser. We implement this intra-cavity selection through the use of two 16 level diffractive optical elements. We consider a solid-state diode side-pumped laser resonator in a typical commercial laser configuration that consists of two planar mirrors where the DOEs are positioned at the mirrors. We out couple the Gaussian and flat-top distributions and we show that we improve the brightness of the laser with active mode control. We also demonstrate that the quality of the beam transformations determine the brightness improvement.
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Paracoccidioidomicose em crianças em Belém do Pará
Directory of Open Access Journals (Sweden)
Fonseca Eliane R.S.
1999-01-01
Full Text Available No período janeiro de 1985 e julho de 1996 foram observados 102 casos de paracoccidioidomicose em hospital de Belém, PA. Treze pacientes eram crianças entre 3 e 13 anos de idade, com predomínio do sexo feminino (8:5. Todos apresentavam a forma disseminada subaguda da micose. É comentada a alta prevalência da micose em crianças em áreas endêmicas da Região Amazônica.
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Kulikov, Alexei N; Maltsev, Dmitrii S; Boiko, Ernest V
2016-01-01
Purpose . To compare three 360°-laser retinopexy (LRP) approaches (using navigated pattern laser system, single-spot slit-lamp (SL) laser delivery, and single-spot indirect ophthalmoscope (IO) laser delivery) in regard to procedure duration, procedural pain score, technical difficulties, and the ability to achieve surgical goals. Material and Methods . Eighty-six rhegmatogenous retinal detachment patients (86 eyes) were included in this prospective randomized study. The mean procedural time, procedural pain score (using 4-point Verbal Rating Scale), number of laser burns, and achievement of the surgical goals were compared between three groups (pattern LRP (Navilas® laser system), 36 patients; SL-LRP, 28 patients; and IO-LRP, 22 patients). Results . In the pattern LRP group, the amount of time needed for LRP and pain level were statistically significantly lower, whereas the number of applied laser burns was higher compared to those in the SL-LRP group and in the IO-LRP group. In the pattern LRP, SL-LRP, and IO-LRP groups, surgical goals were fully achieved in 28 (77.8%), 17 (60.7%), and 13 patients (59.1%), respectively ( p > 0.05). Conclusion . The navigated pattern approach allows improving the treatment time and pain in postoperative 360° LRP. Moreover, 360° pattern LRP is at least as effective in achieving the surgical goal as the conventional (slit-lamp or indirect ophthalmoscope) approaches with a single-spot laser.
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International Nuclear Information System (INIS)
Winburn, D.C.
1985-01-01
This book includes discussions of the following topics: characteristics of lasers; eye components; skin damage thresholds; classification of lasers by ANSI Z136.1; selecting laser-protective eyewear; hazards associated with lasers; and, an index
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International Nuclear Information System (INIS)
2014-01-01
The Laser Technology Program of IPEN is developed by the Center for Lasers and Applications (CLA) and is committed to the development of new lasers based on the research of new optical materials and new resonator technologies. Laser applications and research occur within several areas such as Nuclear, Medicine, Dentistry, Industry, Environment and Advanced Research. Additional goals of the Program are human resource development and innovation, in association with Brazilian Universities and commercial partners
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LASERS: A cryogenic slab CO laser
Ionin, Andrei A.; Kozlov, A. Yu; Seleznev, L. V.; Sinitsyn, D. V.
2009-03-01
A compact capacitive transverse RF-discharge-pumped slab CO laser with cryogenically cooled electrodes, which operates both in the cw and repetitively pulsed regimes, is fabricated. The laser operation is studied in the free running multifrequency regime at the vibrational - rotational transitions of the fundamental (V + 1 → V) vibrational bands of the CO molecule in the spectral region from 5.1 to 5.4 μm. Optimal operation conditions (gas mixture composition and pressure, RF pump parameters) are determined. It is shown that only gas mixtures with a high content of oxygen (up to 20% with respect to the concentration of CO molecules) can be used as an active medium of this laser. It is demonstrated that repetitively pulsed pumping is more efficient compared to cw pumping. In this case, quasi-cw lasing regime can be obtained. The maximum average output power of ~12 W was obtained for this laser operating on fundamental bands and its efficiency achieved ~14 %. The frequency-selective operation regime of the slab RF-discharge-pumped CO laser was realised at ~ 100 laser lines in the spectral region from 5.0 to 6.5 μm with the average output power of up to several tens of milliwatts in each line. Lasing at the transitions of the first vibrational overtone (V + 2 → V) of the CO molecule is obtained in the spectral region from 2.5 to 3.9 μm. The average output power of the overtone laser achieved 0.3 W. All the results were obtained without the forced gas mixture exchange in the discharge chamber. Under fixed experimental conditions, repetitively pulsed lasing (with fluctuations of the output characteristics no more than ±10 %) was stable for more than an hour.
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Energy Technology Data Exchange (ETDEWEB)
Guimaraes Filho, Arlindo Lopes
2004-07-01
Periodontal disease is caused by dental plaque and dental calculus on roots surfaces, specially on cervical areas. As dental plaque is the main cause and dental calculus a secondary one, it is practically impossible to separate one factor to the other one. In order to get periodontal tissue health it is necessary to eliminate dental plaque and calculus from root surfaces. In this sense, Er:YAG laser comes in as an excellent way to control periodontal disease, not only, by removing calculus and dental plaque but also for its bacteria reduction. The aim of this study is to compare, by S.E.M., root surfaces changing when they are treated with curettes and ultrasonic scaling or Er:YAG laser irradiation with two different energy levels of 60 mJ/pulse and 100 mJ/pulse and repetition tax of 10 Hz (in the display). It is also objective of this study to check a possible thermic damage to pulp tissue when the roots surfaces are irradiated with Er:YAG laser. We used for this study, five human dental roots, each one of them were cut into four samples, giving us a total of twenty samples, which were divided in five groups of four samples each one. The control group, we did not indicated any kind of treatment. The first group, the roots samples were scaled and planned with Gracey curettes 5/6 and 7/8. The second group, the roots samples were treated with ultrasonic instruments. The third group was irradiated with Er:YAG laser using 60 mJ/pulse , 10 Hz and energy density of 4 J/cm{sup 2} (approximated). The fourth group was irradiated with Er:YAG laser using 100 mJ/pulse, 10 Hz and energy density of 7 J/cm{sup 2} (approximated). The results analysis showed that roots scaling either with Gracey curettes or with ultrasonic instruments created smear layer covering roots surfaces; roots surfaces irradiated with Er:YAG laser showed few roughness in the third group; roots surfaces irradiated with Er:YAG laser showed no smear layer and the Er:YAG laser irradiation did not bring any
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Directory of Open Access Journals (Sweden)
Hye Suck An
2012-08-01
Full Text Available <em>Mytilus coruscusem> (family Mytilidae is one of the most important marine shellfish species in Korea. During the past few decades, this species has become endangered due to the loss of habitats and overfishing. Despite this species’ importance, information on its genetic background is scarce. In this study, we developed microsatellite markers for <em>M.
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Energy Technology Data Exchange (ETDEWEB)
Mello, Fabiano Augusto Sfier de
2000-07-01
The Er:YAG laser has been studied as a periodontal therapies, used to remove subgingival calculus and its bactericidal effects. The proposal of this study is to evaluate the effectiveness of the Er:YAG laser in root planing in comparison to the traditional method, not surgical. Six recently extracted due to the disease periodontal, were cut longitudinally, tends like this two half of the root. These half were separate in four groups. The first group is the natural tooth (group controls negative), the second group (group controls) was accomplished to root planing with Gracey curette. And in the third to Er:YAG laser with a contact tip, using a 45 deg angle in relation to the root; in the fourth group was scraped and planned with Er:YAG laser and complemented root planing with Gracey curette. The used energy was of 100 mJ (out put) and the frequency of 10 Hz accomplished with irrigation. The obtained results were similar in the groups 2 and 3 in comparison to the amount of smear-layer. In group 4 however, better result was obtained, because the image (SEM) was much more regular and with less amount of smear-layer. The conclusion of the work is that with the association of the laser technique and Gracey curette the results are superior to the conventional treatment. (author)
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Laser Stabilization with Laser Cooled Strontium
DEFF Research Database (Denmark)
Christensen, Bjarke Takashi Røjle
The frequency stability of current state-of-the-art stabilized clock lasers are limited by thermal fluctuations of the ultra-stable optical reference cavities used for their frequency stabilization. In this work, we study the possibilities for surpassing this thermal limit by exploiting the nonli......The frequency stability of current state-of-the-art stabilized clock lasers are limited by thermal fluctuations of the ultra-stable optical reference cavities used for their frequency stabilization. In this work, we study the possibilities for surpassing this thermal limit by exploiting...... the nonlinear effects from coupling of an optical cavity to laser cooled atoms having a narrow transition linewidth. Here, we have realized such a system where a thermal sample of laser cooled strontium-88 atoms are coupled to an optical cavity. The strontium-88 atoms were probed on the narrow 1S0-3P1 inter......-combination line at 689 nm in a strongly saturated regime. The dynamics of the atomic induced phase shift and absorption of the probe light were experimentally studied in details with the purpose of applications to laser stabilization. The atomic sample temperature was in the mK range which brought this system out...
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Measurements of laser parameters for the Shiva laser fusion facility
International Nuclear Information System (INIS)
Ozarski, R.G.
1979-01-01
Large laser systems require numerous laser diagnostics to provide configuration, performance and maintenance data to permit efficient operation. The following diagnostics for a large laser system named Shiva are discussed: (1) description of Shiva laser system, (2) what measurements are desired and or required and why, (3) what measurement techniques and packages are employed and a brief description of the operating principles of the sensors employed, and (4) the laser diagnostic data acquisition and display system
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Directory of Open Access Journals (Sweden)
Yi Zhao
2012-08-01
Full Text Available High permittivity (<em>k> gate dielectric films are widely studied to substitute SiO2 as gate oxides to suppress the unacceptable gate leakage current when the traditional SiO2 gate oxide becomes ultrathin. For high-<em>k> gate oxides, several material properties are dominantly important. The first one, undoubtedly, is permittivity. It has been well studied by many groups in terms of how to obtain a higher permittivity for popular high-<em>k> oxides, like HfO2 and La2O3. The second one is crystallization behavior. Although it’s still under the debate whether an amorphous film is definitely better than ploy-crystallized oxide film as a gate oxide upon considering the crystal boundaries induced leakage current, the crystallization behavior should be well understood for a high-<em>k> gate oxide because it could also, to some degree, determine the permittivity of the high-<em>k> oxide. Finally, some high-<em>k> gate oxides, especially rare earth oxides (like La2O3, are not stable in air and very hygroscopic, forming hydroxide. This topic has been well investigated in over the years and significant progresses have been achieved. In this paper, I will intensively review the most recent progresses of the experimental and theoretical studies for preparing higher-<em>k> and more stable, in terms of hygroscopic tolerance and crystallization behavior, Hf- and La-based ternary high-<em>k> gate oxides.
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Directory of Open Access Journals (Sweden)
Richele P. Severino
2012-07-01
Full Text Available The lipase B from <em>Candida antarcticaem> (Novozym 435®, CALB efficiently catalyzed the kinetic resolution of some aliphatic secondary alcohols: (±-4-methylpentan-2-ol (1, (±-5-methylhexan-2-ol (3, (±-octan-2-ol (4, (±-heptan-3-ol (5 and (±-oct-1-en-3-ol (6. The lipase showed excellent enantioselectivities in the transesterifications of racemic aliphatic secondary alcohols producing the enantiopure alcohols (>99% <em>ee> and acetates (>99% <em>ee> with good yields. Kinetic resolution of <em>rac>-alcohols was successfully achieved with CALB lipase using simple conditions, vinyl acetate as acylating agent, and hexane as non-polar solvent.
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Directory of Open Access Journals (Sweden)
Hélio A. Oliveira
1994-06-01
Full Text Available Os autores apresentam estudo retrospectivo da poliomielite em Sergipe. Dividem o estudo em três períodos levando em consideração a taxa de notificação de casos positivos e enfatizam o período que vai de 1979 a 1989, pelo estudo de 159 casos consecutivos. As seguintes informações foram levantadas para cada caso: sexo, idade, procedência, estado vacinai anterior e evolução clínica. São também avaliadas a incidência anual, relação incidência/cobertura vacinai e distribuição geográfica. Tecem comentários sobre os surtos epidêmicos ocorridos em 1984 e 1986, sobre as alterações na circulação do poliovírus selvagem (P1 para P3 e sobre problemas relacionados à não aquisição de imunidade em crianças com esquema vacinal completo. Consideram a poliomielite controlada no Estado, mas enfatizam a necessidade de manutenção de Vigilância epidemiológica efetiva para todos os casos de paralisia aguda e flácida em menores de 14 anos de idade.
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Laser beam-plasma plume interaction during laser welding
Hoffman, Jacek; Moscicki, Tomasz; Szymanski, Zygmunt
2003-10-01
Laser welding process is unstable because the keyhole wall performs oscillations which results in the oscillations of plasma plume over the keyhole mouth. The characteristic frequencies are equal to 0.5-4 kHz. Since plasma plume absorbs and refracts laser radiation, plasma oscillations modulate the laser beam before it reaches the workpiece. In this work temporary electron densities and temperatures are determined in the peaks of plasma bursts during welding with a continuous wave CO2 laser. It has been found that during strong bursts the plasma plume over the keyhole consists of metal vapour only, being not diluted by the shielding gas. As expected the values of electron density are about two times higher in peaks than their time-averaged values. Since the plasma absorption coefficient scales as ~N2e/T3/2 (for CO2 laser radiation) the results show that the power of the laser beam reaching the metal surface is modulated by the plasma plume oscillations. The attenuation factor equals 4-6% of the laser power but it is expected that it is doubled by the refraction effect. The results, together with the analysis of the colour pictures from streak camera, allow also interpretation of the dynamics of the plasma plume.
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Para-hydrogen raman laser and its application to laser induced chemistry
International Nuclear Information System (INIS)
Tashiro, Hideo
1988-01-01
The report outlines the mechanism of the para-hydrogen Raman laser as a infrared light source, and its application to laser induced chemistry. The Stoke's wave number after a Raman shift is equal to the difference between the wave number of the CO 2 laser used for excitation and the rotation Raman wave number of the hydrogen molecule. A Raman laser can serve as an infrared source. CO 2 laser oscillation beam in the range of 9∼11 micrometers is selected and the frequency of infrared beam is varied by changing the wave number of the CO 2 laser beam. A problem with the Raman laser is that the Raman scatterring gain is small due to a large wavelength. In developing equipment, a special mechanism is required to solve this problem. A Raman laser comprises a CO 2 laser for excitation and multi-pulse Raman cells. The combination of a TEA oscillator and amplifiers gives CO 2 pulses with a peak power of about several tens of MW. Many heavy metal compounds including fluorides, carbonyl compounds and other organic compounds, absorb light with wavelengths in the same range as those of the Raman laser. Such compounds can be dissociated directly by applying Raman laser beams. The laser will be helpful for separation of isotopes, etc. (Nogami, K.)
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Steen, William
2010-01-01
This text moves from the basics of laser physics to detailed treatments of all major materials processing techniques for which lasers are now essential. New chapters cover laser physics, drilling, micro- and nanomanufacturing and biomedical laser processing.
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ANÁLISE DA PERMEAÇÃO DE NANOLIPÍDEOS EM CABELO HUMANO
Directory of Open Access Journals (Sweden)
Ivana Matos Buck Gomes
2017-03-01
Full Text Available Para eficácia da hidratação do cabelo, por meio de produtos com nanopartículas é necessário a permeação nas camadas da fibra capilar. Diante disso, o objetivo deste trabalho foi detectar e analisar espectros correspondentes à permeação de nanolipídeos no fio de cabelo humano, através do uso da Espectroscopia Raman Confocal (ERC. Foram adquiridas amostras comerciais de cabelos de cor loiro descolorido. As amostras foram divididas em dois grupos; Grupo A “controle”, o qual não foi tratado, e Grupo B tratado com um shampoo com alto poder de hidratação com presença de nanolipídeos. Procederam-se as análises com um sistema de Espectroscopia Raman Confocal da Rivers diagnostics (model 3510 skin composition analyzer com laser de 785 nm (400 - 1800 cm-1. Foi observado a permeação dos nanolipídeos na fibra capilar até a profundidade de 16 micrometros. Assim, conclui-se que a ERC é uma ferramenta com grande eficácia para análises de permeações de cosméticos em cabelos.
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Michaelis, M. M.; Forbes, A.; Bingham, R.; Kellett, B. J.; Mathye, A.
2008-05-01
A variety of laser applications in space, past, present, future and far future are reviewed together with the contributions of some of the scientists and engineers involved, especially those that happen to have South African connections. Historically, two of the earliest laser applications in space, were atmospheric LIDAR and lunar ranging. These applications involved atmospheric physicists, several astronauts and many of the staff recruited into the Soviet and North American lunar exploration programmes. There is a strong interest in South Africa in both LIDAR and lunar ranging. Shortly after the birth of the laser (and even just prior) theoretical work on photonic propulsion and space propulsion by laser ablation was initiated by Georgii Marx, Arthur Kantrowitz and Eugen Saenger. Present or near future experimental programs are developing in the following fields: laser ablation propulsion, possibly coupled with rail gun or gas gun propulsion; interplanetary laser transmission; laser altimetry; gravity wave detection by space based Michelson interferometry; the de-orbiting of space debris by high power lasers; atom laser interferometry in space. Far future applications of laser-photonic space-propulsion were also pioneered by Carl Sagan and Robert Forward. They envisaged means of putting Saenger's ideas into practice. Forward also invented a laser based method for manufacturing solid antimatter or SANTIM, well before the ongoing experiments at CERN with anti-hydrogen production and laser-trapping. SANTIM would be an ideal propellant for interstellar missions if it could be manufactured in sufficient quantities. It would be equally useful as a power source for the transmission of information over light year distances. We briefly mention military lasers. Last but not least, we address naturally occurring lasers in space and pose the question: "did the Big Bang lase?"
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Determinação de hemogregarina em Boa constrictor constrictor mantidos em cativeiro
Directory of Open Access Journals (Sweden)
Monique A. Luz
2012-08-01
Full Text Available O presente estudo teve como objetivo determinar a presença de hemogregarina em boídeos mantidos em cativeiro no Estado do Pará, bem como, relacionar a hemoparasitose com pre-disposição sexual, alterações clínicas e hematológicas e a presença de ectoparasitos. Esta pesquisa teve autorização do Sistema de Autorização e Informação em Biodiversidade do Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis para ser realizado. Utilizaram-se 19 serpentes da família Boidae mantidas em cativeiro, pertencentes ao "Museu Paraense Emilio Goeldi" (Belém/PA e "Sítio Xerimbabo" (Santo Antônio do Tauá/PA. A pesquisa de hemogregarina foi realizada em esfregaços sanguíneos examinados no aumento de 400x, enquanto que a parasitemia foi determinada contando- se 550 hemácias em aumento de 1000x. Do total de animais estudados (n=19, nove encontraram-se parasitados (47,36%, não havendo correlação entre presença de hemogregarina, pré-disposição sexual, alterações clínicas e hematológicas nas serpentes hospedeiras. A correlação da hemoparasitose foi detectada apenas quanto à presença de ectoparasitas nas serpentes, no entanto, estudos adicionais são necessários para verificar a prevalência de hemogregarinas em animais mantidos em cativeiro no Estado do Pará, visto que, existe grande lacuna de dados na literatura veterinária especializada no que diz respeito à fauna da região amazônica.
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RENDENÇÃO E CONFORMISMO EM UMA LINDA MULHER Redenção e conformismo em Uma Linda Mulher
Directory of Open Access Journals (Sweden)
Alexander Martins Vianna
2011-07-01
Full Text Available
Este artigo pretende demonstrar a forma como os temas da rendenção individual e do conformismo social são acionados no desenvolvimento da trama nostálgica e na caracterização dos personagens principais do filme “<em style="mso-bidi-font-style: normal;">Uma Linda Mulherem>”, assim como, visa a demonstrar o quanto que tais temas estão referidos a um <em style="mso-bidi-font-style: normal;">habitusem> <em style="mso-bidi-font-style: normal;">culturalem> que determina escolhas conjunturais de estereótipos raciais/morais e de formas estéticas que configuram um tipo de emoção para o enredo que leva à aceitação da <em style="mso-bidi-font-style: normal;">solução caridosa burguesa em>‘
Este artigo pretende demonstrar a forma como os temas da rendenção individual e do conformismo social são acionados no desenvolvimento da trama nostálgica e na caracterização dos personagens principais do filme “<em style="mso-bidi-font-style: normal;">Uma Linda Mulherem>”, assim como, visa a demonstrar o quanto que tais temas estão referidos a um <em style="mso-bidi-font-style: normal;">habitusem> <em style="mso-bidi-font-style: normal;">culturalem> que determina escolhas conjunturais de estereótipos raciais/morais e de formas estéticas que configuram um tipo de emoção para o enredo que leva à aceitação da <em style -
Frequency-doubled diode laser for direct pumping of Ti:sapphire lasers
DEFF Research Database (Denmark)
Müller, André; Jensen, Ole Bjarlin; Unterhuber, Angelika
2012-01-01
. However, the superior electro-optical efficiency of the diode laser improves the overall efficiency of the Ti:sapphire laser by a factor > 2. The optical spectrum emitted by the Ti:sapphire laser shows a spectral width of 112 nm (FWHM). Based on autocorrelation measurements, pulse widths of less than 20...... fs are measured. These results open the opportunity of establishing diode laser pumped Ti:sapphire lasers for e.g. biophotonic applications like retinal optical coherence tomography or pumping of photonic crystal fibers for CARS microscopy.......A single-pass frequency doubled high-power tapered diode laser emitting nearly 1.3 W of green light suitable for direct pumping of Ti:sapphire lasers generating ultrashort pulses is demonstrated. The pump efficiencies reached 75 % of the values achieved with a commercial solid-state pump laser...
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Directory of Open Access Journals (Sweden)
Yu-Chung Chiang
2012-05-01
Full Text Available The landrace strains of <em>Momordica charantia em>are widely cultivated vegetables throughout the tropics and subtropics, but not in Taiwan, a continental island in Southeast Asia, until a few hundred years ago. In contrast, the related wild populations with smaller fruit sizes are native to Taiwan. Because of the introduction of cultivars for agricultural purposes, these two accessions currently exhibit a sympatric or parapatric distribution in Taiwan. In this study, the cultivars<em> em>and wild samples from Taiwan, India, and Korea<em> em>were collected for testing of their hybridization and evolutionary patterns. The cpDNA marker showed a clear distinction between accessions of cultivars and wild populations of Taiwan and a long divergence time. In contrast, an analysis of eight selectively neutral nuclear microsatellite loci did not reveal a difference between the genetic structures of these two accessions. A relatively short divergence time and frequent but asymmetric gene flows were estimated based on the isolation-with-migration model. Historical and current introgression from cultivars to wild populations of Taiwan was also inferred using MIGRATE-n and BayesAss analyses. Our results showed that these two accessions shared abundant common ancestral polymorphisms, and the timing of the divergence and colonization of the Taiwanese wild populations is consistent with the geohistory of the Taiwan Strait land bridge of the Last Glacial Maximum (LGM. Long-term and recurrent introgression between accessions indicated the asymmetric capacity to receive foreign genes from other accessions. The modern introduction of cultivars of <em>M>. <em>charantia> during the colonization of Taiwan by the Han Chinese ethnic group enhanced the rate of gene replacement in the native populations and resulted in the loss of native genes.
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International Nuclear Information System (INIS)
Fantoni, R.
1988-01-01
This lecture deals with laser induced material photoprocessing, especially concerning those processes which are initiated by u.v. lasers (mostly excimer laser). Advantages of using the u.v. radiation emitted by excimer lasers, both in photophysical and photochemical processes of different materials, are discussed in detail. Applications concerning microelectronics are stressed with respect to other applications in different fields (organic chemistry, medicine). As further applications of excimer lasers, main spectroscopic techniques for ''on line'' diagnostics which employ excimer pumped dye lasers, emitting tunable radiation in the visible and near u.v. are reviewed
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Technological laser application
International Nuclear Information System (INIS)
Shia, D.O.; Kollen, R.; Rods, U.
1980-01-01
Problems of the technological applications of lasers are stated in the popular form. Main requirements to a technological laser as well as problems arising in designing any system using lasers have been considered. Areas of the laser applications are described generally: laser treatment of materials, thermal treatment, welding, broach and drilling of holes, scribing, microtreatment and adjustment of resistors, material cutting, investigations into controlled thermonuclear fussion
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Directory of Open Access Journals (Sweden)
Ligang Zhou
2012-05-01
Full Text Available Water-extracted mycelial polysaccharide (WPS from the endophytic fungus <em>Fusarium oxysporumem> Dzf17 isolated from <em>Dioscorea zingiberensisem> was found to be an efficient elicitor to enhance diosgenin accumulation in<em> D. zingigerensisem> cultures, and also demonstrated antioxidant activity. In this study, response surface methodology (RSM was employed to optimize the extraction process of WPS from <em>F
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Effects of laser fluence on silicon modification by four-beam laser interference
International Nuclear Information System (INIS)
Zhao, Le; Li, Dayou; Wang, Zuobin; Yue, Yong; Zhang, Jinjin; Yu, Miao; Li, Siwei
2015-01-01
This paper discusses the effects of laser fluence on silicon modification by four-beam laser interference. In this work, four-beam laser interference was used to pattern single crystal silicon wafers for the fabrication of surface structures, and the number of laser pulses was applied to the process in air. By controlling the parameters of laser irradiation, different shapes of silicon structures were fabricated. The results were obtained with the single laser fluence of 354 mJ/cm 2 , 495 mJ/cm 2 , and 637 mJ/cm 2 , the pulse repetition rate of 10 Hz, the laser exposure pulses of 30, 100, and 300, the laser wavelength of 1064 nm, and the pulse duration of 7–9 ns. The effects of the heat transfer and the radiation of laser interference plasma on silicon wafer surfaces were investigated. The equations of heat flow and radiation effects of laser plasma of interfering patterns in a four-beam laser interference distribution were proposed to describe their impacts on silicon wafer surfaces. The experimental results have shown that the laser fluence has to be properly selected for the fabrication of well-defined surface structures in a four-beam laser interference process. Laser interference patterns can directly fabricate different shape structures for their corresponding applications
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A bricolage na pesquisa em educação em enfermagem: Relato de experiência
Directory of Open Access Journals (Sweden)
Leonara Raddai Gunther de Campos
2016-01-01
Full Text Available RESUMO Introdução: Este artigo apresenta um relato de experiência sobre a utilização da bricolage em uma pesquisa educacional em enfermagem. Objetivo: Relatar a experiência do uso da bricolage. Métodos: Primeiramente, foi realizado um levantamento bibliográfico sobre o termo e sua utilização em meio científico, em seguida, as autoras apresentam a experiência da aplicação do método em uma pesquisa de Mestrado em Enfermagem. A bricolage possibilitou a combinação de estratégias para a construção dos dados, como a observação participante, entrevista semiestruturada, análise documental e gravação em áudio das sessões tutoriais. A análise dos dados foi uma etapa bem peculiar e criativa, onde as autoras, amparadas pela bricolage criaram seu próprio processo de análise. Conclusões: Dentre os principais resultados são ressaltados as vantagens proporcionadas pela utilização da bricolage, como a captação dos aspectos multilógicos dos fenômenos e desafios. Implicações para a prática: Este relato contribui com novas opções metodológicas para estudos em enfermagem.
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Directory of Open Access Journals (Sweden)
Lucia Caloi
1986-12-01
Full Text Available Abstract Biometric data from the examination of skulls of <em>Hippopotamus pentlandiem> Von Meyer (Canninita cave, Palermo, Sicily are compared with the data relative to the skulls of two fossil hippos of european Pleistocene and of the living species <em>Hippopotamus amphibiusem> Linnaeus. Even taking into account the inhomogeneity of the fossil specimens and the deformation suffered by the skulls of <em>H. pentlandiem> from Cannita cave, the examination confirms on one hand the stronger affinity of the sicilian species with the living <em>H. amphibiusem> and from the other hand the peculiarities that characterize this form with respect to the european continental ones. A comparative examination of the biometric characters of the skull of these latter species confirms the greater distance of <em>H. antiquusem> Desmarest from the living species. It is stressed how the relations between the less bulky Pleistocene species (<em>Hippopotamus incognitusem> Faure with <em>H. antiquusem> and with the living <em>H. amphibiusem> have not yet been completely clarified, owing both to the scantiness of the documentation and to the strong variability observed in the biometric characters of the few known skulls. It is noted how, in any case, this fossil form appears more similar to the living <em>H. amphibiusem>. For the moment its distinction at a specific level is accepted, even if with reservation, taking into account also the distinctive elements recognized in the post-cranial skeleton (FAURE, 1985, not examined here. Riassunto Vengono analizzati e posti a confronto i dati biometrici ricavati dall'analisi dei crani di <em>Hippopotamus pentlandiem> Von Heyer della Grotta della Cannita (Palermo, Sicilia, degli ippopotami fossili del Pleistocene continentale europeo e della specie vivente <em>Hippopotamus amphibiusem> Linnaeus. Vengono da un lato confermate le maggiori affinità tra <em>H. pentlandiem
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Energy Technology Data Exchange (ETDEWEB)
Youssef, Fernanda de Almeida
2004-07-01
The aim of this in vitro study was to evaluate the degree of marginal microleakage in occlusal sealing by invasive techniques, after preparation with Er:YAG laser followed or not by Er:YAG laser etching and compared to the conventional technique. Thirty human premolars were divided into three groups: A (control group) - cavities were prepared with high speed and etched with 37% orthophosphoric acid; group B - cavities were prepared with Er:YAG (350 mJ, 4 Hz and 112 J /cm{sup 2}) and etched with 37% orthophosphoric acid; group C - cavities were prepared with Er:YAG laser (350 mJ, 4 Hz and 112 J/cm{sup 2}), and etched with Er:YAG laser (80 mJ, 4 Hz and 25 m/cm{sup 2}). All cavities were treated with the same adhesive system and restored with flow composite according to manufacturer instructions. Teeth were submitted to thermal cycling procedures and immersed in 50% Silver Nitrate Solutions for 8 hours in total darkness. Teeth were sectioned longitudinally in the bucco-lingual direction, in slices of 1 mm thick. Each slice was immersed into photo developing solution under 16 hours of fluorescent light. Slices were photographed and microleakage was scored from 0 to 7 J by three standard examiners. Results showed statistically significant differences for group C (Er:YAG laser preparation and etching). We concluded that Er:YAG laser can be used for cavity preparation of occlusal sealing, like the conventional high speed method. However, this laser, used as enamel etching agent, could not promote an adequate surface for adhesive procedures. (author)
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Laser innovated manufacturing technology; Laser ga seisan gijutsu wo kakushinshita
Energy Technology Data Exchange (ETDEWEB)
Maruyama, I. [Honda Motor Co. Ltd., Tokyo (Japan)
1996-11-01
This paper looks back the history of applications of laser processing in the automobile industry, and introduces contents of some particularly unique applications from among them. The CO2 laser and YAG laser that are used mainly have increased their outputs with the times, and 50-kW CO2 laser and 4-kW YAG laser have now become available commercially. The laser processing has become used widely for cutting purpose in Japan, which is in contrast with their high application to welding in Europe and America. Cutting thick plates has been developed recently, which is applicable to plates as thick as about 25 mm. A flexible system in which YAG laser is combined with an optical fiber/articulated robot is operating for three-dimensional shape processing. Automobile makers are adopting laser processing for welding in place of the electron beam welding that has been used conventionally. The process is used also for a number of other applications including surface reformation, such as surface quenching for cylinder liner, and valve seat padding. 8 refs., 8 figs.
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Enfermagem em cardiologia baseada em evidência
Directory of Open Access Journals (Sweden)
Eneida Rejane Rabelo da Silva
2007-10-01
Full Text Available Neste artigo apresentamos, dentro do cenário cardiovascular, estudos recentes do nosso grupo. Buscando melhores evidências de enfermagem investigamos por meio de ensaios clínicos randomizados (ECR estratégias de educação e acompanhamento destes pacientes (pctes. O primeiro ECR avaliou o impacto da educação individual e da orientação em grupo no conhecimento sobre doença e autocuidado em pctes com insuficiência cardíaca (IC. No grupo intervenção, houve uma melhora do conhecimento dos cuidados essenciais (controle de sal e da ingesta hídrica, peso diário, realização de atividade física P=0,008, demonstrando que o atendimento em grupo é semelhante ao individual. No ambiente hospitalar, segundo ECR, comparamos o efeito da educação de enfermagem e seguimento telefônico após alta versus educação sem a monitorização por telefone. Demonstramos que intervenção educativa durante a internação melhora o conhecimento da doença, autocuidado e qualidade de vida (P
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A new karyotype of <em>Calomyscus> from the Khorasan Province, Iran
Directory of Open Access Journals (Sweden)
Esmaeeli Somayeh
2008-07-01
Full Text Available Abstract We report a new karyotype of <em>Calomyscus> from two localities of the Khorasan Province (Aghdarband, 36° 11’ 3”N, 60° 44’ 6” E and Khajemorad, 36° 8’ 5” N, 59° 41’ 58” E. Chromosomes were examined by conventional staining and C-banding techniques. The diploid chromosome number (2n and the fundamental autosomal arm number (FNa were 44 and 60 respectively. The autosomal set consisted of 12 pairs of telocentrics, 5 pairs of acrocentrics and 4 pairs of sub-metacentrics. Both heterosomes were small telocentrics. Riassunto Un nuovo cariotipo del genere <em>Calomyscus> dalla provincia di Khorasan, Iran. Si descrive un nuovo cariotipo appartenente al genere <em>Calomyscus>, scoperto in due località della provincia di Khorasan (Aghdarband, 36° 11’ 3”N, 60° 44’ 6” E e Khajemorad, 36° 8’ 5” N, 59° 41’ 58” E. I cromosomi sono stati analizzati con le tecniche standard di colorazione e bandeggio. Il numero diploide di cromosomi (2n e il numero fondamentale di bracci autosomici sono risultati pari a 44 e 60 rispettivamente. Il set di cromosomi autosomici è composto da 12 paia di telocentrici, 5 di acrocentrici e 4 di sub-metacentrici. Entrambi i cromosomi sessuali si presentano come piccoli telocentrici.
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DEFF Research Database (Denmark)
Khoryushin, Alexey V.; Mozhaev, Peter B.; Mozhaeva, Julia E.
2013-01-01
The effects of excess yttria on the structural and electrical properties of the YBa2Cu3Ox (YBCO) thin films are studied. The films were deposited on (LaAlO3)0.3–(Sr2AlTaO8)0.7 substrates by pulsed laser ablation from targets with different elemental composition. An increase of yttrium content of ...
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Directory of Open Access Journals (Sweden)
Olorunnisola Sinbad Olorunnisola
2012-05-01
Full Text Available The present study examines the effect of methanolic extract of <em>T. violaceaem> rhizomes on high cholesterol (2% diet fed rats (HCD. At the end of 4 weeks, serum total protein, albumin, reduced glutathione (GSH, and markers of oxidative stress viz., catalase (CAT, superoxide dismutase (SOD, thiobarbituric acid reactive substances (TBARS—a marker of lipid peroxidation, glutathione-S-transferase (GST and glutathione peroxidase (GPx in the serum, aorta, liver and heart of HCD and normal rats were assessed and compared. A significant (<em>p> < 0.05 elevation in TBARS, and a reduction (<em>p> < 0.05 in serum total protein, albumin, GSH and antioxidant enzyme activities was observed in tissues of HCD fed rats compared with the normal group. Co-administration of crude extracts of <em>T. violaceaem> rhizomes protected the liver, heart, serum and aorta against HCD-induced lipid peroxidation in a dose dependant manner. The activities of the extract (500 mg/kg compared favorably with gemfibrozil. The extracts also protected against HCD-induced reduction in serum total protein, GSH and restored the activities of antioxidant tissues (liver, heart and aorta enzymes to near normal values. This result suggested that consumption of <em>T. violaceaem> rhizome may help to protect against hypercholesterolemia- induced oxidative stress diseases in the heart and liver.
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Energy Technology Data Exchange (ETDEWEB)
Ferrreira, Marcus Vinicius Lucas
2000-07-01
The aim of this study was to evaluate the effects of pulsed Nd:YAG (1064 nm) laser irradiation on hydroxyapatite and enamel powder fusion. This laser beam is not well absorbed by this two compounds for this reason they were mixed with vegetal coal to increase the absorption of the laser beam. Fifteen enamel flat surfaces and six occlusal enamel surfaces were prepared with three different substances: hydroxyapatite mixed with vegetal coal (3:1 in weigh); enamel powder mixed with vegetal coal (3:1 in weigh); vegetal coal. The occlusal surfaces were utilized to determine if the compounds could seal pits and fissures. Flat surfaces were utilized to determine fusion of hydroxyapatite and enamel powder. All samples were irradiated with Nd:YAG laser with the parameters: 80 mJ, 15 Hz, 1,2 W, 100 {mu}s pulse-width, 131,1 J/cm{sup 2}. Laser beam was delivered to the samples with a 300 {mu}m diameter fiber optic. Morphology of the irradiated surfaces were examined by scanning electron microscopy (SEM). The compounds with hydroxyapatite and enamel powder were fused to enamel surfaces. Only partial pits and fissures sealing could be observed. (author)
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Directory of Open Access Journals (Sweden)
Ernesto Cesar Pinto Leal Junior
2010-12-01
Full Text Available A fadiga muscular é uma nova área de pesquisa em laserterapia, com poucos estudos conduzidos. Embora a laserterapia de baixa potência (LBP previamente ao exercício tenha apresentado resultados positivos no retardo da fadiga musculoesquelética, ainda não foi estudada utilizando-se a dinamometria isocinética para mensurar desempenho e fadiga muscular. Este estudo tem o objetivo de avaliar os efeitos da LBP (655 nm, 50 mW, 2,4 J por ponto e 12 J de energia total sobre o desempenho e fadiga muscular do músculo tibial anterior, utilizando dinamometria isocinética (30 repetições de contração concêntrica em 14 indivíduos saudáveis sedentários do sexo masculino. Os voluntários foram avaliados ao efetuar 30 repetições isocinéticas de dorsiflexão de tornozelo à velocidade angular de 240°.seg-1. Os resultados mostram que, quando os voluntários foram tratados com LBP antes do exercício, os valores do pico de torque (30,91±5,86 N.m foram significativamente superiores, comparados a três medições anteriores sem a aplicação de LBP (24,92±7,45 N.m, pSkeletal muscle fatigue is a novel research area in laser therapy, there being few studies carried out. Though low-level laser therapy (LLLT applied prior to exercise has showed positive results in delaying skeletal muscle fatigue, no studies could be found that measured muscle performance and fatigue by means of isokinetic dynamometry. This clinical trial aims at assessing the effects of LLLT (655 nm, 50 mW and 12 J total energy delivered on anterior tibialis muscle performance and fatigue by means of isokinetic dynamometry (30 concentric-mode repetitions at 240º.sec-1 angular speed in 14 healthy male subjects. Results show that, when volunteers had been treated with LLLT prior to exercise, torque peak values (30.91±5.86 N.m were significantly higher than those of three previous measurements with no LLLT (24.92±7.45 N.m, p<0.001; 26.83±7.74 N.m, p<0.01; and 26.00±7.88 N.m, p<0
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The Mercury Laser Advances Laser Technology for Power Generation
Energy Technology Data Exchange (ETDEWEB)
Ebbers, C A; Caird, J; Moses, E
2009-01-21
The National Ignition Facility (NIF) at Lawrence Livermore Laboratory is on target to demonstrate 'breakeven' - creating as much fusion-energy output as laser-energy input. NIF will compress a tiny sphere of hydrogen isotopes with 1.8 MJ of laser light in a 20-ns pulse, packing the isotopes so tightly that they fuse together, producing helium nuclei and releasing energy in the form of energetic particles. The achievement of breakeven will culminate an enormous effort by thousands of scientists and engineers, not only at Livermore but around the world, during the past several decades. But what about the day after NIF achieves breakeven? NIF is a world-class engineering research facility, but if laser fusion is ever to generate power for civilian consumption, the laser will have to deliver pulses nearly 100,000 times faster than NIF - a rate of perhaps 10 shots per second as opposed to NIF's several shots a day. The Mercury laser (named after the Roman messenger god) is intended to lead the way to a 10-shots-per-second, electrically-efficient, driver laser for commercial laser fusion. While the Mercury laser will generate only a small fraction of the peak power of NIF (1/30,000), Mercury operates at higher average power. The design of Mercury takes full advantage of the technology advances manifest in its behemoth cousin (Table 1). One significant difference is that, unlike the flashlamp-pumped NIF, Mercury is pumped by highly efficient laser diodes. Mercury is a prototype laser capable of scaling in aperture and energy to a NIF-like beamline, with greater electrical efficiency, while still running at a repetition rate 100,000 times greater.
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Directory of Open Access Journals (Sweden)
Daqing Shi
2012-07-01
Full Text Available A series of 3'-aminospiro[indoline-3,1'-pyrazolo[1,2-<em>b>]phthalazine]-2,5',10'-trione derivatives have been synthesized by a one-pot three-component reaction of isatin, malononitrile or ethyl cyanoacetate and phthalhydrazide catalyzed by piperidine under ultrasound irradiation. For comparison the reactions were carried out under both conventional and ultrasonic conditions. In general, improvement in rates and yields were observed when the reactions were carried out under sonication compared with classical conditions.
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International Nuclear Information System (INIS)
Storm, E.; Coleman, L.W.
1985-01-01
The objectives of the Lawrence Livermore National Laboratory Laser Fusion program are to understand and develop the science and technology of inertial confinement fusion (ICF), and to utilize ICF in short- and long-term military applications, and, in the long-term, as a candidate for central-station civilian power generation. In 1984, using the Novette laser system, the authors completed experiments showing the very favorable scaling of laser-plama interactions with short-wavelength laser light. Their Novette experiments have unequivocally shown that short laser wavelength, i.e., less than 1 μm, is required to provide the drive necessary for efficient compression, ignition, and burn of DT fusion fuel. In other experiments with Novette, the authors made the first unambiguous observation of amplified spontaneous emission in the soft x-ray regime. The authors also conducted military applications and weapons physics experiments, which they discuss in detail in the classified volume of our Laser Program Annual Report. In the second thrust, advanced laser studies, they develop and test the concepts, components, and materials for present and future laser systems. Over the years, this has meant providing the technology base and scientific advances necessary to construct and operate a succession of six evermore-powerful laser systems. The latest of these, Nova, a 100-TW/100-kJ-class laser system, was completed in 1984. The Nd:glass laser continues to be the most effective and versatile tool for ICF and weapons physics because of its scalability in energy, the ability to efficiently convert its 1=μm output to shorter wavelengths, its ability to provide flexible, controlled pulse shaping, and its capability to adapt to a variety of irradiation and focusing geometries. For these reasons, many of our advanced laser studies are in areas appropriate to solid state laser technologies
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Energy Technology Data Exchange (ETDEWEB)
Tannous, Jose Trancoso
2001-07-01
This is a morphological analysis study through SEM of the differences of the laser tissue interaction as a function of the laser beam irradiation angle, under different parameters of energy. Fourteen freshly extracted molars stored in a 0,9% sodium chloride solution were divided in seven pairs and were irradiated with 100, 200, 300, 400, 500, 600 and 700 mJ per pulse, respectively. Each sample received three enamel irradiations and three cement irradiations, either in the punctual or in the contact mode, one near to the other, with respectively 30, 45 and 90 inclinations degrees of dental surface-laser-beam incidence. Four Er:YAG pulses (2,94 {mu}m, 7-20 Hz, 0,1-1 J energy/pulse - Opus 20 - Opus Dent) with water cooling system (0,4 ml/s) were applied. After the laser irradiation the specimens were analysed through scanning electron microscope (SEM). The results were analysed by SEM micrographs showing a great difference on the laser tissue interaction characteristics as a function of the irradiation angle of the laser beam. All the observations led to conclude that, considering the laser parameters used, the incidence angle variation is a very important parameter regarding the desired morphological effects. This represents an extremely relevant detail on the technical description of the Er:YAG laser irradiation protocols on dental tissues. (author)
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Power balancing of multibeam laser fusion lasers
International Nuclear Information System (INIS)
Seka, W.; Morse, S.; Letzring, S.; Kremens, R.; Kessler, T.J.; Jaanimagi, P.; Keck, R.; Verdon, C.; Brown, D.
1989-01-01
The success of laser fusion depends to a good degree on the ability to compress the target to very high densities of ≥1000 times liquid DT. To achieve such compressions require that the irradiation nonuniformity must not exceed ∼1% rms over the whole time of the compression, particularly during the early phases of irradiation. The stringent requirements for the irradiation uniformity for laser fusion have been known for quite some time but until recently the energy balance was mistakenly equated to power balance. The authors describe their effort on energy balance and irradiation patterns on the target. They significantly improved the laser performance with respect to overall intensity distributions on target including the implementation of distributed (random) phase plates in each high power beam. However, the slightly varying performance of the third harmonic conversion crystals in the twenty-four beams of their laser system was generally compensated for by appropriately adjusted 1.054μm input laser energy. Computational analysis of the results of the recent high density campaign are shown
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Energy Technology Data Exchange (ETDEWEB)
Gourley, P.L.; Gourley, M.F.
2000-10-05
Laser technology has advanced dramatically and is an integral part of today's healthcare delivery system. Lasers are used in the laboratory analysis of human blood samples and serve as surgical tools that kill, burn or cut tissue. Recent semiconductor microtechnology has reduced the size o f a laser to the size of a biological cell or even a virus particle. By integrating these ultra small lasers with biological systems, it is possible to create micro-electrical mechanical systems that may revolutionize health care delivery.
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An overview of the laser ranging method of space laser altimeter
Zhou, Hui; Chen, Yuwei; Hyyppä, Juha; Li, Song
2017-11-01
Space laser altimeter is an active remote sensing instrument to measure topographic map of Earth, Moon and planetary. The space laser altimeter determines the range between the instrument and laser footprint by measuring round trip time of laser pulse. The return pulse reflected from ground surface is gathered by the receiver of space laser altimeter, the pulsewidth and amplitude of which are changeable with the variability of the ground relief. Meantime, several kinds of noise overlapped on the return pulse signal affect its signal-to-noise ratio. To eliminate the influence of these factors that cause range walk and range uncertainty, the reliable laser ranging methods need to be implemented to obtain high-precision range results. Based on typical space laser altimeters in the past few decades, various ranging methods are expounded in detail according to the operational principle of instruments and timing method. By illustrating the concrete procedure of determining time of flight of laser pulse, this overview provides the comparison of the employed technologies in previous and undergoing research programs and prospect innovative technology for space laser altimeters in future.
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Novel laterally pumped by prism laser configuration for compact solid-state lasers
International Nuclear Information System (INIS)
Dascalu, T; Salamu, G; Sandu, O; Voicu, F; Pavel, N
2013-01-01
We propose a new laser configuration in which the pump radiation is coupled into the laser crystal through a prism. The laser medium is square shaped and the prism is attached on one of its lateral sides, near one of the crystal extremities. The diode-laser fiber end is placed close to the prism hypotenuse, the pump radiation is coupled into the laser crystal through the opposite surface of the prism and propagates into the crystal through total internal reflections. This laser geometry is simple to align and permits the realization of compact diode-pumped laser systems, as well as power scaling. A diode-pumped Nd:YAG laser yielding pulses of 2.1 mJ energy under a pump with pulses of 9.9 mJ is demonstrated. The laser slope efficiency is 0.22. Furthermore, this geometry enables one to obtain passively Q-switched lasers with the saturable absorber crystal placed between the resonator high-reflectivity mirror and the laser crystal. A Nd:YAG laser, passively Q-switched by a Cr 4+ :YAG crystal with initial transmission T 0 = 0.90, delivering laser output with a pulsed energy of 93 μJ, a duration of 26 ns and a pump threshold of 1.9 mJ, is realized in order to prove the concept. (letter)
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A Laser Technology Test Facility for Laser Inertial Fusion Energy (LIFE)
International Nuclear Information System (INIS)
Bayramian, A.J.; Campbell, R.W.; Ebbers, C.A.; Freitas, B.L.; Latkowski, J.; Molander, W.A.; Sutton, S.B.; Telford, S.; Caird, J.A.
2010-01-01
A LIFE laser driver needs to be designed and operated which meets the rigorous requirements of the NIF laser system while operating at high average power, and operate for a lifetime of >30 years. Ignition on NIF will serve to demonstrate laser driver functionality, operation of the Mercury laser system at LLNL demonstrates the ability of a diode-pumped solid-state laser to run at high average power, but the operational lifetime >30 yrs remains to be proven. A Laser Technology test Facility (LTF) has been designed to specifically address this issue. The LTF is a 100-Hz diode-pumped solid-state laser system intended for accelerated testing of the diodes, gain media, optics, frequency converters and final optics, providing system statistics for billion shot class tests. These statistics will be utilized for material and technology development as well as economic and reliability models for LIFE laser drivers.
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Directory of Open Access Journals (Sweden)
Qinqin Cui
2012-06-01
Full Text Available <em>Litsea cubebaem> (Lour. Pers. is a promising industrial crop with fruits rich in essential oils. The chemical composition of essential oils of <em>L. cubebaem> (EOLC were determined for fruits harvested from eight regions in China. The overall essential oil content, obtained by hydrodistillation and analyzed by gas chromatography–mass spectrometry (GC-MS, ranged from 3.04% to 4.56%. In total, 59 compounds were identified, the dominant components being monoterpenes (94.4–98.4%, represented mainly by neral and geranial (78.7–87.4%. D-Limonene was unexpectedly a lesser constituent (0.7–5.3% in fruits, which differed from previous reports (6.0–14.6%. Several components were only detected in certain regions and compounds such as <em>o>-cymene and eremophilene have never before been reported in EOLC. These results demonstrate significant regional variation in the chemical composition of EOLC. This investigation provides important information with regard to the bioactivity, breeding work and industrial applications of <em>L. cubebaem>.
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International Nuclear Information System (INIS)
Akeel, H.A.
1987-01-01
A robot-laser system is described for providing a laser beam at a desired location, the system comprising: a laser beam source; a robot including a plurality of movable parts including a hollow robot arm having a central axis along which the laser source directs the laser beam; at least one mirror for reflecting the laser beam from the source to the desired location, the mirror being mounted within the robot arm to move therewith and relative thereto to about a transverse axis that extends angularly to the central axis of the robot arm; and an automatic programmable control system for automatically moving the mirror about the transverse axis relative to and in synchronization with movement of the robot arm to thereby direct the laser beam to the desired location as the arm is moved
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Energy Technology Data Exchange (ETDEWEB)
Li, Shuo; Chen, Rongzhang; Nelsen, Bryan; Chen, Kevin, E-mail: pec9@pitt.edu [Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Liu, Lei; Huang, Xi; Lu, Yongfeng [Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 (United States)
2016-03-15
This paper reports the development of a compact and portable actively Q-switched Nd:YAG laser and its applications in laser-induced breakdown spectroscopy (LIBS). The laser was end-pumped by a vertical-cavity surface-emitting laser (VCSEL). The cavity lases at a wavelength of 1064 nm and produced pulses of 16 ns with a maximum pulse energy of 12.9 mJ. The laser exhibits a reliable performance in terms of pulse-to-pulse stability and timing jitter. The LIBS experiments were carried out using this laser on NIST standard alloy samples. Shot-to-shot LIBS signal stability, crater profile, time evolution of emission spectra, plasma electron density and temperature, and limits of detection were studied and reported in this paper. The test results demonstrate that the VCSEL-pumped solid-state laser is an effective and compact laser tool for laser remote sensing applications.
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International Nuclear Information System (INIS)
Breisland, H.O.
1991-01-01
The neodymium YAG laser is particularly suited for endoscopic urologic surgery because the YAG laser light can be conducted in flexible fibers. Superficial bladder tumours can be treated under local anaesthesia in the outpatient department. The frequency of local recurrences is low, significantly lower than after electrosection or electrocoagulation. Selected cases of T2-muscle invasive bladder tumours can be cured with laser coagulation applied subsequently to transurethral resection. Combined treatment with electrosection and laser coagulation of localized prostatic cancer is a promising method which compares favourably with results obtained by other treatment modalities. Tumours in the upper urinary tract can be laser-treated through ureteroscopes or nephroscopes, but the treatment should be limited to low stage, low grade tumours. Laser is the treatment of choice for intraurethral condylomatas. Laser treatment of penil carcinoma gives excellent cosmetic and functional results and few local recurrences. Laser lithotripsy is a new technique for treatment of ureteric stones and photodynamic laser therapy is a promising tecnique for treatment of carcinoma in situ in the bladder empithelium. However, neither of these techniques are available for clinical use in Norway as yet. 17 refs., 3 figs., 1 tabs
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International Nuclear Information System (INIS)
Green, W.R.
1979-01-01
This dissertation discusses some of the new ways that lasers can be used to control the energy flow in a medium. Experimental and theoretical considerations of the laser-induced collision are discussed. The laser-induced collision is a process in which a laser is used to selectively transfer energy from a state in one atomic or molecular species to another state in a different species. The first experimental demonstration of this process is described, along with later experiments in which lasers were used to create collisional cross sections as large as 10 - 13 cm 2 . Laser-induced collisions utilizing both a dipole-dipole interaction and dipole-quadrupole interaction have been experimentally demonstrated. The theoretical aspects of other related processes such as laser-induced spin-exchange, collision induced Raman emission, and laser-induced charge transfer are discussed. Experimental systems that could be used to demonstrate these various processes are presented. An experiment which produced an inversion of the resonance line of an ion by optical pumping of the neutral atom is described. This type of scheme has been proposed as a possible method for constructing VUV and x-ray lasers
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Directory of Open Access Journals (Sweden)
Leen van Ofwegen
2012-06-01
Full Text Available Nine new compounds, namely sinularones A–I (1–9, characterized as cyclopentenone and butenolide-type analogues, were isolated from a soft coral <em>Sinularia> sp., together with a known butenolide (10. Their structures were elucidated by means of spectroscopic (IR, MS, 1D and 2D NMR, CD analysis. The absolute configurations were determined on the basis of CD and specific rotation data in association with the computed electronic circular dichroism (ECD by time dependent density functional theory (TD DFT at 6-31+G(<em>d,p>//DFT B3LYP/6-31+G(<em>d,p> level. Compounds 1–2 and 7–10 showed potent antifouling activities against the barnacle <em>Balanus amphitriteem>.
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Directory of Open Access Journals (Sweden)
Thiago Y. Fukuda
2010-08-01
Full Text Available CONTEXTUALIZAÇÃO: A laserterapia de baixa intensidade (LBI vem sendo cada vez mais utilizada, porém ainda não há consenso na literatura quanto ao tempo em que os equipamentos devem ser submetidos à aferição ou calibragem. OBJETIVO: Analisar a potência média real (PmR dos equipamentos de LBI na região da Grande São Paulo. MÉTODOS: Para análise dos equipamentos, utilizou-se um potenciômetro (Lasercheck, próprio para aferição de equipamentos contínuos, o qual foi programado com dados referentes ao comprimento de onda do laser a ser avaliado, obtendo-se assim a PmR emitida. Os equipamentos foram analisados de duas formas: uma, com o LBI desaquecido, e outra, após 10 minutos de uso (aquecido, sendo que três análises foram feitas para cada condição. A caneta emissora foi acoplada ao potenciômetro, o qual fornecia a PmR emitida pelo LBI. Todos os dados e informações referentes à aplicação do laser foram coletados por um questionário respondido pelos responsáveis. RESULTADOS: Os 60 equipamentos avaliados mostraram déficit na PmR com os equipamentos desaquecidos e aquecidos. A análise estatística (ANOVA mostrou diminuição significativa (PBACKGROUND: Despite the increase in the use of low-level laser therapy (LLLT, there is still a lack of consensus in the literature regarding how often the equipment must be calibrated. OBJECTIVE: To evaluate the real average power of LLLT devices in the Greater São Paulo area. METHODS: For the evaluation, a LaserCheck power meter designed to calibrate continuous equipment was used. The power meter was programmed with data related to the laser's wavelength to gauge the real average power being emitted. The LLLT devices were evaluated in two ways: first with the device cooled down and then with the device warmed up for 10 minutes. For each condition, three tests were performed. The laser probe was aligned with the power meter, which provided the real average power being emitted by the
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Directory of Open Access Journals (Sweden)
Streck Nereu Augusto
2005-01-01
Full Text Available O meloeiro (Cucumis melo L. é uma hortaliça de alto valor econômico. A emissão de nós é um componente importante em modelos matemáticos de simulação do crescimento e desenvolvimento de culturas de hábito de crescimento decumbente como o meloeiro e outras cucurbitáceas. A emissão de nós pode ser calculada utilizando-se o conceito do plastocrono, que é o intervalo de tempo entre o aparecimento de nós sucessivos em uma haste de dicotiledôneas. Quando a soma térmica é usada como medida de tempo fisiológico em plantas, o plastocrono tem como unidades degreesC dia nó-1. Estudos anteriores mostraram que o plastocrono em meloeiro varia com o genótipo e a época de cultivo. Este trabalho teve por objetivo estimar o plastocrono em meloeiro transplantado em diferentes épocas de cultivo no interior de estufa plástica. Foram realizadas 12 épocas de semeadura e transplante no interior de uma estufa plástica de 10m X 25m, coberta com polietileno transparente de baixa densidade, localizada no Campo Experimental do Departamento de Fitotecnia da Universidade Federal de Santa Maria, RS. O híbrido utilizado foi o HY-MARK (grupo Cantaloupe. Em 12 plantas etiquetadas por época de transplante, contou-se o número de nós visíveis (NN na haste principal da planta duas vezes por semana. A soma térmica diária (STd, degreesC dia foi calculada levando-se em conta as temperaturas cardinais de aparecimento de nós em meloeiro (10, 34 e 45degreesC. A soma térmica acumulada (STa, degreesC dia, a partir da data de transplante das plântulas, foi calculada somando-se a STd. O plastocrono foi calculado como sendo o inverso do coeficiente angular da regressão linear entre NN e STa para cada época. O plastocrono calculado variou entre as épocas de cultivo de 13,4 a 21,8degreesC dia nó-1, com um valor médio de 18,6 (?2,3degreesC dia nó-1. Esta diferença de plastocrono entre as épocas de cultivo pode representar vários dias do calendário civil
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Multimegajoule laser project: new compact multipass laser design
International Nuclear Information System (INIS)
Holzrichter, J.F.
1985-01-01
A simple laser design that has the fewest laser components of all fusion systems that the authors have studied and that packs closely, thus minimizing space requirements is shown. The Advanced Laser Program objectives are determined by the requirements of the subsystems. The requirements consists of the following elements: high damage thresholds on reflectors; AR layers and dichroic coatings; high-efficiency amplifiers; low-cost production of laser glass, pulse power, and optical elements; and special optical elements, such as an effective phase conjugator and isolator. The combination of a compact architecture and lower-cost, higher-performance components can lead to significant reduction in overall system cost
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International Nuclear Information System (INIS)
Bohn, Willy L.
2008-01-01
First, an introductory overview of the different types of laser propulsion techniques will be given and illustrated by some historical examples. Second, laser devices available for basic experiments will be reviewed ranging from low power lasers sources to inertial confinement laser facilities. Subsequently, a status of work will show the impasse in which the laser propulsion community is currently engaged. Revisiting the basic relations leads to new avenues in ablative and direct laser propulsion for ground based and space based applications. Hereby, special attention will be devoted to the impact of emerging ultra-short pulse lasers on the coupling coefficient and specific impulse. In particular, laser sources and laser propulsion techniques will be tested in microgravity environment. A novel approach to debris removal will be discussed with respect to the Satellite Laser Ranging (SRL) facilities. Finally, some non technical issues will be raised aimed at the future prospects of laser propulsion in the international community
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Directory of Open Access Journals (Sweden)
Cibele Nazaré da Silva Câmara
2011-02-01
Full Text Available Purpose: Analyze the influence of low-intensity laser therapy in the sciatic nerve regeneration of rats submitted to controlled crush through histological analysis. Methods: Were used 20 Wistar rats, to analyze the influence of low-intensity laser therapy in the sciatic nerve regeneration, where the injury of the type axonotmesis was induced by a haemostatic clamp Crile (2nd level of the rack. The animals were randomly distributed in 2 groups. Control group (CG n = 10 and Laser group (LG n = 10. These were subdivided in 2 subgroups each, according to the euthanasia period: (CG14 _ n = 5 and CG21 _ n = 5 and (LG14 _ n = 5 and LG21 _ n = 5. At the end of treatment, the samples were removed and prepared for histological analysis, where were analyzed and quantified the following findings: Schwann cells, myelinic axons with large diameter and neurons. Results: In the groups submitted to low-intensity laser therapy, were observed an increase in the number of all analyzed aspects with significance level. Conclusion: The irradiation with low intensity laser (904nm influenced positively the regeneration of the sciatic nerve in Wistar rats after being injured by crush (axonotmesis, becoming the nerve recovery more rapid and efficient.Objetivo: Verificar a influência da terapia com laser de baixa potência na regeneração histológica do nervo ciático de ratos submetidos à neuropraxia controlada. Métodos: Foi utilizada a amostra de 20 ratos da linhagem Wistar, para verificar a influência da terapia com laser de baixa intensidade na regeneração nervosa periférica, onde a lesão do tipo axoniotmese foi induzida por meio de preensão com pinça hemostática de Crile. Os animais foram distribuídos randomicamente dois grupos. Grupo controle (CG n = 10, e Grupo laser (LG n = 10. Cada um destes grupos foi subdividido em dois subgrupos dependendo do período da eutanásia: (CG14 - n = 5 e CG21 - n = 5 e (LG14 - n = 5 e LG21 - n = 5. Ao final do
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Distributed feedback dye laser pumped with copper-vapor laser emission
Energy Technology Data Exchange (ETDEWEB)
Mirza, S Yu; Soldatov, A N; Sukhanov, V B
1983-10-01
The power-spectrum characteristics of the emission of a distributed feedback dye laser pumped with a copper vapor laser have been studied. Laser action has been observed in five dyes over a tuning range of 530-723 nm with an efficiency of 12.4%. The specfic features of the distributed feedback dye laser operating at pulse repetition rates of 4 kHz are discussed.
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Energy Technology Data Exchange (ETDEWEB)
Carvalho, Wendell Lima de
2003-07-01
Microleakage is one of the most important reasons to restorations failure, it is the responsible for marginal colors changing, new caries, hipersensibility and pulpar diseases. Several techniques and materials have been studied to eliminate or, at least, to decrease microleakage. The cavities preparation with Er:YAG laser and autoconditioning adhesive are some of these techniques and materials. This research has the objective to compare, in vitro, microleakage in class V cavities, prepared with high rotation (conventional treatment), Er:YAG laser (Enamel-400 mj/2 Hz/128,38 J/Cm{sup 2}, Dentin 250 mJ/ 2 Hz/ 80,24 J/Cm{sup 2}) and the treatment made at dentin with autoconditioning adhesive (Clerafil SE Bond) using Er:YAG laser (with water or not water) or not using Er:YAG laser. It was used 48 bovines teeth with cavities prepared in vestibular face and gingival wall on cement enamel junction and oclusal wall on enamel. The materials used were autoconditioning adhesive (Clerafil SE Bond) and composite resin Z250. Teeth were divided into four groups of twelve samples each one, according to dentin treatment. Group 1 - Conventional cavity and autoconditioning adhesive. Group 2- Cavity prepared with Er: YAG laser and autoconditioning adhesive. Group 3 - Cavity prepared with Er:YAG laser and dentin conditioning with Er:YAG laser associated to water and autoconditioning adhesive. Group 4 - Cavity prepared with Er:YAG laser and dentin conditioning with Er: YAG laser without water and associated to autoconditioning adhesive. Teeth were restored and stocked at 37 deg C, thermocycled and placed into a 50% silver nitrate solution. Right after, teeth were sliced and evaluated on a stereo microscopic magnifying glass in order to see microleakage degree trying to follow a score from 0 to 3. The findings were submitted to Fisher, Anderson-Darling tests and to the not parametric Sen and Puri test. The results indicated that in gingival edge, the Group 2 showed less microleakage than
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Directory of Open Access Journals (Sweden)
Telma Pereira
2001-11-01
Full Text Available Objetivo: Analisar a incidência, tipo, tratamento e evolução das complicações em LASIK. Métodos: Estudo retrospectivo de 1000 olhos submetidos a LASIK usando os microceratótomos Hansatome® ou Automated Corneal Shaper® e os aparelhos de Excimer Laser VISX 20/20B ou Chiron Technolas 217C. Complicações peroperatórias e pós-operatórias precoces e tardias foram analisadas. Resultados: A média do equivalente esférico pré-operatório foi de -4,29 ± 3,20D. A média do seguimento foi de 6,05 ± 6,69 meses. No período peroperatório foram encontradas cinco (0,5% complicações do disco relacionadas ao microceratótomo (3 discos finos, 1 disco com perfuração central e 1 disco pequeno. As complicações mais freqüentes no período pós-operatório precoce foram as dobras de disco (6,4%, seguidas de debris na interface (4,1%, ceratite não específica da interface (1,1%, "haze" (0,4%, crescimento epitelial da interface (0,4% e deslocamento de disco (0,3%. A maioria destes eventos foi prontamente tratada, alcançando-se bons resultados. Para as complicações tardias, relacionadas à refração, foram analisados 655 olhos que apresentavam seguimento mínimo de 3 meses. No último exame, a média do equivalente esférico neste grupo foi de -0,26±0,76D. Oito por cento dos olhos encontravam-se com hipocorreção superior a 1,00D; e 1,67% com hipercorreção > 1,00D. Retratamento foi necessário em 28 olhos (4,27%. Cinco casos (0,76% perderam de 2 ou mais linhas da melhor acuidade visual corrigida. Não foram observadas outras complicações visualmente importantes. Conclusão: LASIK é um procedimento refrativo seguro e com poucas complicações.Purpose: To analyze the incidence, type, management and evolution of complications in laser in situ keratomileusis (LASIK. Methods: Retrospective non-comparative case series. LASIK was performed in 1000 eyes using the Hansatome® or the Automated Corneal Shaper® microkeratomes, and the VISX 20/20B
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Influence of the laser pulse duration on laser-produced plasma properties
International Nuclear Information System (INIS)
Drogoff, B Le; Margot, J; Vidal, F; Laville, S; Chaker, M; Sabsabi, M; Johnston, T W; Barthelemy, O
2004-01-01
In the framework of laser-induced plasma spectroscopy (LIPS) applications, time-resolved characteristics of laser-produced aluminium plasmas in air at atmospheric pressure are investigated for laser pulse durations ranging from 100 fs to 270 ps. Measurements show that for delays after the laser pulse longer than ∼100 ns, the plasma temperature increases slightly with the laser pulse duration, while the electron density is independent of it. In addition, as the pulse duration increases, the plasma radiation emission lasts longer and the spectral lines arise later from the continuum emission. The time dependence of the continuum emission appears to be similar whatever the duration of the laser pulse is, while the temporal evolution of the line emission seems to be affected mainly by the plasma temperature. Finally, as far as spectrochemical applications (such as LIPS) of laser-produced plasmas are concerned, this study highlights the importance of the choice of appropriate temporal gating parameters for each laser pulse duration
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Antibacterial Secondary Metabolites from the Cave Sponge <em>Xestospongia em>sp.
Directory of Open Access Journals (Sweden)
Sridevi Ankisetty
2012-05-01
Full Text Available Chemical investigation of the cave sponge <em>Xestospongia em>sp. resulted in the isolation of three new polyacetylenic long chain compounds along with two known metabolites. The structures of the new metabolites were established by NMR and MS analyses. The antibacterial activity of the new metabolites was also evaluated.
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Laser cleaning of pulsed laser deposited rhodium films for fusion diagnostic mirrors
International Nuclear Information System (INIS)
Uccello, A.; Maffini, A.; Dellasega, D.; Passoni, M.
2013-01-01
Highlights: ► Pulsed laser deposition is exploited to produce Rh films for first mirrors. ► Pulsed laser deposition is exploited to produce tokamak-like C contaminants. ► Rh laser damage threshold has been evaluated for infrared pulses. ► Laser cleaning of C contaminated Rh films gives promising results. -- Abstract: In this paper an experimental investigation on the laser cleaning process of rhodium films, potentially candidates to be used as tokamak first mirrors (FMs), from redeposited carbon contaminants is presented. A relevant issue that lowers mirror's performance during tokamak operations is the redeposition of sputtered material from the first wall on their surface. Among all the possible techniques, laser cleaning, in which a train of laser pulses is launched to the surface that has to be treated, is a method to potentially mitigate this problem. The same laser system (Q-switched Nd:YAG laser with a fundamental wavelength of 1064-nm and 7-ns pulses) has been employed with three aims: (i) production by pulsed laser deposition (PLD) of Rh film mirrors, (ii) production by PLD of C deposits with controlled morphology, and (iii) investigation of the laser cleaning method onto C contaminated Rh samples. The evaluation of Rh films laser damage threshold, as a function of fluence and number of pulses, is discussed. Then, the C/Rh films have been cleaned by the laser beam. The exposed zones have been characterized by visual inspection and scanning electron microscopy (SEM), showing promising results
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International Nuclear Information System (INIS)
Liu Jichang; Li Lijun; Zhang Yuanzhong; Xie Xiaozhu
2005-01-01
The power of a focused laser beam with a Gaussian intensity profile attenuated by powder in coaxial laser cladding is investigated experimentally and theoretically, and its resolution model is developed. With some assumptions, it is concluded that the attenuation of laser power is an exponential function and is determined by the powder feed rate, particle moving speed, spraying angles and waist positions and diameters of the laser beam and powder flow, grain diameter and run of the laser beam through the powder flow. The attenuation of laser power increases with powder feed rate or run of laser beam through the powder flow. In the experiment presented, 300 W laser power from a focused Gaussian beam is attenuated by a coaxial powder flow. The experimental results agree well with the values calculated with the developed model
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Directory of Open Access Journals (Sweden)
Tássio Dresch Rech
2006-09-01
Full Text Available A intensidade de dormência e o requerimento em frio do vimeiro (Salix x rubens Shrank foram avaliados pelo método de estacas de gema isolada. As observações foram realizadas em ramos coletados em Lages, SC, a intervalos regulares de 21 dias, de 29/03/2004 a 2/08/2004. A brotação de gemas dos segmentos basal, mediano e distal de ramos do ano foi avaliada na ausência ou após suplementação de frio (500 ou de 1000 horas a 5 3ºC. A brotação de gemas foi avaliada nos estádios: a gemas inchadas; b início da abertura das gemas; c broto alongado e; d broto alongado com folha aberta. A intensidade de dormência das gemas foi crescente da base para a ponta dos ramos e foi máxima em 10 de maio, para todas as regiões do ramo. O tratamento com 500 horas de frio foi efetivo em reduzir o tempo para a brotação, em todas as épocas e posições das gemas no ramo. A avaliação até o aparecimento de folhas abertas foi importante para identificar a real capacidade de brotação das gemas.
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Duarte, FJ
2008-01-01
Introduction F. J. Duarte Spectroscopic Applications of Tunable Optical Parametric Oscillators B. J. Orr, R. T. White, and Y. He Solid-State Dye Lasers Costela, I. García-Moreno, and R. Sastre Tunable Lasers Based on Dye-Doped Polymer Gain Media Incorporating Homogeneous Distributions of Functional Nanoparticles F. J. Duarte and R. O. James Broadly Tunable External-Cavity Semiconductor Lasers F. J. Duarte Tunable Fiber Lasers T. M. Shay and F. J. Duarte Fiber Laser Overview and Medical Applications
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Laser Scanner Terrestre: teoria, aplicações e prática
Directory of Open Access Journals (Sweden)
Rodrigo da Silva Ferraz
2016-06-01
Full Text Available A utilização de um Sistema de Varredura Laser Terrestre (SVLT possui inúmeras aplicações nas diversas áreas envolvidas em levantamentos tridimensionais. Possui ampla utilização na mineração para cálculos de volumes, registro de monumentos históricos, geração de modelos digitais de superfície (MDS, modelos digitais de terreno (MDT e aplicações na arquitetura. O produto principal gerado por um SVLT é uma nuvem de pontos com coordenadas tridimensionais referenciadas ao centro de fase do sensor, que, após processos matemáticos denominado de registro, gera uma nuvem de pontos georreferenciada. Além das coordenadas tridimensionais o SVLT fornece também a intensidade de retorno do sinal, que é a energia captada pelo sensor em função da resposta espectral emitida pelo alvo. Dependendo das características do sistema, à nuvem de pontos pode-se adicionar cores a partir de fotografias das cenas que são obtidas durante as varreduras. As nuvens de pontos modelam diferentes tipos de feições existentes no terreno como vegetação, edificações, rochas, estruturas, etc. Assim, o objetivo desse trabalho é realizar uma abordagem dos principais conceitos envolvidos em relação a um SVLT, classificação de dados oriundos das nuvens de pontos e suas aplicações na geração de MDT.
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Directory of Open Access Journals (Sweden)
Rodrigo Pegado de Abreu Freitas
2013-03-01
Full Text Available Este estudo teve o objetivo de investigar se há diferenças entre as terapias associadas e isoladas do laser e microcorrentes no reparo de lesão por queimadura em ratos. Um total de 40 animais foi dividido aleatoriamente em quatro grupos: grupo controle (GC; grupo microcorrente (GM, grupo laser (GL e grupo laser/microcorrente (GLM, tratados com laser associado a microcorrentes. Após lesões térmicas induzidas no dorso do animal, foi realizado um total de dez dias de tratamento. Amostras do tecido foram coletadas para estudo histopatológico semiquantitativo com Hematoxilina Eosina e Tricrômico de Masson. Foram utilizados os testes de Kruskal-Wallis e post-hoc de Dunn. Houve diferença significativa entre os grupos para a produção de fibroblastos (p=0,0003, colágeno (p=0,0153, neoangiogênese (p=0,0031 e anexos cutâneos (p=0,0004. Na análise histológica semiquantitativa, o GLM apresentou valores menores nos parâmetros histológicos de presença de colágeno, número de fibroblastos e anexos cutâneos (pEste estudio tiene el objetivo de investigar si hay diferencias entre las terapias asociadas y aisladas del láser y microcorrientes en la reparación de lesión por quemadura en ratas. Un total de 40 animales fueron divididos aleatoriamente en cuatro grupos: grupo control (GC, grupo microcorriente (GM, grupo láser (GL y grupo láser/microcorriente (GLM, tratados con láser asociado a microcorrientes. Después de inducidas las lesiones térmicas en el dorso del animal, fueron realizados en total diez días de tratamiento. Las muestras de tejido fueron recolectadas para el estudio histopatológico semicuantitativo usando Hematoxilina Eosina y Tricómico de Masson. Fueron utilizados los tests de Kruskal-Wallis y post-hoc de Dunn's. Hubo diferencia significativa entre los grupos para la producción de fibroblastos (p=0,0003, colágeno (p=0,0153, neoangiogénesis (p=0,0031 y anexos cutáneos (p=0,0004. En el análisis histol
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Directory of Open Access Journals (Sweden)
R. Latini
2003-10-01
Full Text Available Nel Parco Nazionale d'Abruzzo è stata studiata la selezione dell'habitat invernale di cervo e capriolo da aprile a maggio del 2000 e del 2002, in un'area caratterizzata da boschi di faggio, rimboschimenti a pino nero e pascoli. È stata utilizzata la tecnica del <em>pellet group countem>, su transetti lineari larghi 2 metri, individuati ogni 100 m di quota, lungo le isoipse da 1350 a 1950 m s.l.m. Sono stati percorsi 61 km ed è stata campionata un'area di 12 ha. Per ogni gruppo di escrementi (1583 per il cervo e 946 per il capriolo sono state rilevate l'altitudine, la pendenza, l'esposizione e il tipo di vegetazione. È stato assunto che tutti gli habitat fossero ugualmente disponibili ed accessibili e che le disponibilita fossero conosciute (Alldredge <em>et al.em>, 1998. I dati raccolti sono stati elaborati applicando il test del Χ², la statistica di Bonferroni (Neu <em>et al.em>, 1974 e l'indice Jacobs (Jacobs, 1974. Il cervo ha selezionato aree comprese tra 1300 e 1500 m s.l.m. (p<0.01, un range altimetrico più ristretto rispetto al capriolo che seleziona anche le quote piu elevate, comprese cioè tra 1300 e 1700 m s.l.m. (p<0.01. Entrambi i cervidi selezionano le zone più scoscese (21°-60° (p<0.01: Il cervo seleziona le classi d'esposizione comprese tra sud-est ed ovest (p<0.01, mentre il capriolo i versanti sud-ovest e ovest (p<0.01. Entrambe le specie preferiscono ambienti di transizione ed evitano le zone di bosco maturo ed i pascoli d'alta quota (p<0.01. Utilizzando il tasso di defecazione è stata calcolata la densità delle due specie (Mayle, 1999 che è risultata di 2.7 cervi/100 ha e 1.0 caprioli/100 ha. Le due specie selezionano le stesse risorse, suggerendo, così come riscontrato da altri autori (Welch, 1989, una convergenza per quanto riguarda l'uso invernale dell'habitat. La scelta d'aree poste a quote medio-basse, di zone scoscese e di versanti meridionali potrebbe essere legata alla minore altezza e persistenza
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Greco Laser-matter interaction
International Nuclear Information System (INIS)
1986-01-01
Research program in 1985 at GRECO ILM (Group of Coordinated Research: Interaction Laser Matter) continued with its principal direction in fundamental physics of laser inertial confinement; also researches on X-ray lasers hare been undergone and new high power laser application fields with particle acceleration, material processing and X-ray sources. A six beam laser was operated. Wavelength effects were studied. Atomic physics was deeply stressed as dense medium diagnostics from multicharged ions. Research development in ultra-dense medium was also important X-ray laser research gave outstanding results. New research fields were developed this year: laser acceleration of particles by wave beating or Raman instability; dense laser produced plasma use as X-ray source; material processing by laser shocks [fr
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Entrevistas devolutivas em pesquisa em avaliação Psicológica
Nunes, Maiana Farias Oliveira; Noronha, Ana Paula Porto; Ambiel, Rodolfo Augusto Matteo
2012-01-01
Apesar de ser um direito dos participantes, não é comum se observar ações de devolução dos resultados de pesquisas em Psicologia com seres humanos. O presente trabalho consiste em um relato de experiência que tem como objetivo apresentar um processo de devolutiva de dados coletados para um projeto de doutorado, com foco na construção de um instrumento para uso em orientação profissional. Os participantes da pesquisa foram 747 estudantes dos ensinos médio e técnico, de escolas públicas e parti...
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Laser applications in materials processing
International Nuclear Information System (INIS)
Ready, J.F.
1980-01-01
The seminar focused on laser annealing of semiconductors, laser processing of semiconductor devices and formation of coatings and powders, surface modification with lasers, and specialized laser processing methods. Papers were presented on the theoretical analysis of thermal and mass transport during laser annealing, applications of scanning continuous-wave and pulsed lasers in silicon technology, laser techniques in photovoltaic applications, and the synthesis of ceramic powders from laser-heated gas-phase reactants. Other papers included: reflectance changes of metals during laser irradiation, surface-alloying using high-power continuous lasers, laser growth of silicon ribbon, and commercial laser-shock processes
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International Nuclear Information System (INIS)
Suzuki, Kazuya; Iwasaki, Matae
1977-01-01
A review is made of the research and development of HF chemical laser and its related work. Many gaseous compounds are used as laser media successfully; reaction kinetics and technological problems are described. The hybrid chemical laser of HF-CO 2 system and the topics related to the isotope separation are also included. (auth.)
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Conjuntivite em animais de companhia
Gonçalves, Mariana Inês Pereira Coelho
2015-01-01
Dissertação de Mestrado Integrado em Medicina Veterinária, Ciências Veterinárias A conjuntivite é a doença ocular mais frequentemente diagnosticada em Medicina Veterinária, tanto em cães como em gatos. O facto de a conjuntiva ser uma membrana mucosa tão exposta a agentes externos faz com que esteja bastante suscetível a sofrer lesões, com consequente inflamação. Nesta dissertação abordam-se os diferentes tipos de conjuntivite, que são classificados de acordo com a sua etiologia. No Hospita...
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BEING AND DISCOURSE IN PLATO’S PARMENIDES SER E DISCURSO NO <em>PARMÊNIDES> DE PLATÃO
Directory of Open Access Journals (Sweden)
Eliane Christina Souza
2011-03-01
Full Text Available The <em>Parmenides> is known as the dialogue in which Plato makes a criticism of his theory of forms. Through paradoxes, the character Parmenides criticizes the theory of forms presented by Socrates in the dialogue, targeting the relation they have with sensibles and with each other, call for participation, and the discoursive consequences of this relation. I present a reading of the Parmenides that suggests that the self-criticism points out inconsistencies in the Platonic theory of participation as it is presented in the Parmenides, and that will be corrected later in the Sophist.O <em>Parmênides> é conhecido como o diálogo em que Platão faz uma crítica de sua teoria das formas. Através de paradoxos, a personagem Parmênides critica a teoria das formas apresentada por Sócrates no diálogo, tendo como alvo a relação que as formas mantêm com os sensíveis e entre si, chamada de participação, e as consequências discursivas dessa relação. Eu apresento uma leitura do <em>Parmênides> que sugere que a autocrítica platônica aponta inconsistências na teoria da participação tal como ela é apresentada no <em>Parmênides> e que serão corrigidas posteriormente no <em>Sofista>.
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Directory of Open Access Journals (Sweden)
S. Taylor
2012-06-01
Full Text Available In capacitance-voltage (C-V measurements, frequency dispersion in high-<em>k> dielectrics is often observed. The frequency dependence of the dielectric constant (<em>k>-value, that is the intrinsic frequency dispersion, could not be assessed before suppressing the effects of extrinsic frequency dispersion, such as the effects of the lossy interfacial layer (between the high-<em>k> thin film and silicon substrate and the parasitic effects. The effect of the lossy interfacial layer on frequency dispersion was investigated and modeled based on a dual frequency technique. The significance of parasitic effects (including series resistance and the back metal contact of the metal-oxide-semiconductor (MOS capacitor on frequency dispersion was also studied. The effect of surface roughness on frequency dispersion is also discussed. After taking extrinsic frequency dispersion into account, the relaxation behavior can be modeled using the Curie-von Schweidler (CS law, the Kohlrausch-Williams-Watts (KWW relationship and the Havriliak-Negami (HN relationship. Dielectric relaxation mechanisms are also discussed.
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Directory of Open Access Journals (Sweden)
Carlos Henrique A. de Rezende
1997-12-01
Full Text Available Procedeu-se ao controle das enteroparasitoses em manipuladores de alimentos de escolas públicas de primeiro grau de Uberlândia, Minas Gerais, a partir de estudo prospectivo baseado em inquérito parasitológico. Foram acompanhados 264 indivíduos de 57 escolas, com três coletas de fezes (C, sendo C1 em setembro de 1989, C2 em abril de 1990 e C3 em setembro de 1990. Entre os participantes 259 eram do sexo feminino e cinco do sexo masculino, com idades entre 20 e 66 anos. As 792 amostras de fezes foram conservadas em formol a 10% e analisadas pelo método de Hoffman, Pons e Janer. A ocorrência de parasitas intestinais foi de 17, 10 e 10% para C1, C2, e C3, respectivamente. Em C1 detectou-se: Giardia lamblia (8%, ancilostomídeos (6%, Ascaris lumbricoides (3%, Entamoeba histolytica, (2%, Strongyloides stercoralis, Hymenolepis nana, Taenia sp. e Trichuris trichiura (menos de 1% cada um deles. Em C2 detectou-se: ancilostomídeos (5%, G. lamblia (2%, A. lumbricoides (1%, S. stercoralis, H. nana, Taenia sp., Enterobius vermicularis (menos de 1% cada um deles. Em C3 observou-se: ancilostomídeos (5%, G. lamblia (3%, A. lumbricoides (2%, S. stercoralis e E. vermicularis (menos de 1% cada um deles. Os indivíduos infectados receberam tratamento específico após o diagnóstico em cada coleta. Recomendamos a implantação de vigilância epidemiológica através do exame parasitológico periódico, tratamento específico e treinamento sobre manejo higiênico de alimentos e higiene pessoal para todos os manipuladores de alimentos.
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DEFF Research Database (Denmark)
Olsen, Flemming Ove
The appearance of the high power high brilliance fibre laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating cutting laser, the CO2-laser. However, quality problems in fibre......-laser cutting have until now limited its application in metal cutting. In this paper the first results of proof-of-principle studies applying a new approach (patent pending) for laser cutting with high brightness short wavelength lasers will be presented. In the approach, multi beam patterns are applied...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from 2 single mode fibre lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W of single...
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DEFF Research Database (Denmark)
Olsen, Flemming Ove; Hansen, Klaus Schütt; Nielsen, Jakob Skov
2009-01-01
The appearance of the high power high brilliance fiber laser has opened for new possibilities in laser materials processing. In laser cutting this laser has demonstrated high cutting performance compared to the dominating Cutting laser, the CO2 laser. However, quality problems in fiber......-laser cutting have until now limited its application to metal cutting. In this paper the first results of proof-of-principle Studies applying a new approach (patent pending) for laser cutting with high brightness and short wavelength lasers will be presented. In the approach, multibeam patterns are applied...... to control the melt flow out of the cut kerf resulting in improved cut quality in metal cutting. The beam patterns in this study are created by splitting up beams from two single mode fiber lasers and combining these beams into a pattern in the cut kerf. The results are obtained with a total of 550 W...
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Elavarasu, Sugumari; Naveen, Devisree; Thangavelu, Arthiie
2012-08-01
Laser is one of the most captivating technologies in dental practice since Theodore Maiman in 1960 invented the ruby laser. Lasers in dentistry have revolutionized several areas of treatment in the last three and a half decades of the 20(th) century. Introduced as an alternative to mechanical cutting device, laser has now become an instrument of choice in many dental applications. Evidence suggests its use in initial periodontal therapy, surgery, and more recently, its utility in salvaging implant opens up a wide range of applications. More research with better designs are a necessity before lasers can become a part of dental armamentarium. This paper gives an insight to laser in periodontics.
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Laser-driven ion acceleration with hollow laser beams
International Nuclear Information System (INIS)
Brabetz, C.; Kester, O.; Busold, S.; Bagnoud, V.; Cowan, T.; Deppert, O.; Jahn, D.; Roth, M.; Schumacher, D.
2015-01-01
The laser-driven acceleration of protons from thin foils irradiated by hollow high-intensity laser beams in the regime of target normal sheath acceleration (TNSA) is reported for the first time. The use of hollow beams aims at reducing the initial emission solid angle of the TNSA source, due to a flattening of the electron sheath at the target rear side. The experiments were conducted at the PHELIX laser facility at the GSI Helmholtzzentrum für Schwerionenforschung GmbH with laser intensities in the range from 10 18 W cm −2 to 10 20 W cm −2 . We observed an average reduction of the half opening angle by (3.07±0.42)° or (13.2±2.0)% when the targets have a thickness between 12 μm and 14 μm. In addition, the highest proton energies were achieved with the hollow laser beam in comparison to the typical Gaussian focal spot
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Laser-driven ion acceleration with hollow laser beams
Energy Technology Data Exchange (ETDEWEB)
Brabetz, C., E-mail: c.brabetz@gsi.de; Kester, O. [Goethe-Universität Frankfurt am Main, 60323 Frankfurt (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Busold, S.; Bagnoud, V. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Helmholtz-Institut Jena, 07743 Jena (Germany); Cowan, T. [Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden (Germany); Technische Universität Dresden, 01069 Dresden (Germany); Deppert, O.; Jahn, D.; Roth, M. [Technische Universität Darmstadt, 64277 Darmstadt (Germany); Schumacher, D. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany)
2015-01-15
The laser-driven acceleration of protons from thin foils irradiated by hollow high-intensity laser beams in the regime of target normal sheath acceleration (TNSA) is reported for the first time. The use of hollow beams aims at reducing the initial emission solid angle of the TNSA source, due to a flattening of the electron sheath at the target rear side. The experiments were conducted at the PHELIX laser facility at the GSI Helmholtzzentrum für Schwerionenforschung GmbH with laser intensities in the range from 10{sup 18} W cm{sup −2} to 10{sup 20} W cm{sup −2}. We observed an average reduction of the half opening angle by (3.07±0.42)° or (13.2±2.0)% when the targets have a thickness between 12 μm and 14 μm. In addition, the highest proton energies were achieved with the hollow laser beam in comparison to the typical Gaussian focal spot.
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International Nuclear Information System (INIS)
Holzrichter, J.F.
1980-01-01
The ideas that led to the successful construction and operation of large multibeam fusion lasers at the Lawrence Livermore Laboratory are reviewed. These lasers are based on the use of Nd:glass laser materials. However, most of the concepts are applicable to any laser being designed for fusion experimentation. This report is a summary of lectures given by the author at the 20th Scottish University Summer School in Physics, on Laser Plasma Interaction. This report includes basic concepts of the laser plasma system, a discussion of lasers that are useful for short-pulse, high-power operation, laser design constraints, optical diagnostics, and system organization
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Directory of Open Access Journals (Sweden)
Luciana Chucre Gentile
2004-12-01
TODOS: Foram selecionados 32 pacientes, 22 do sexo feminino e 10 do sexo masculino, com idades entre 20-52 anos. Os 32 pacientes foram distribuídos de maneira aleatória em dois grupos, um tratado e outro controle, um total de 68 dentes compôs a amostra, sendo que 35 compuseram o grupo tratado, e 33 o grupo controle. O grupo tratado foi submetido a seis sessões sucessivas de irradiações em intervalos de 48 a 72 horas, o grupo controle recebeu como placebo aplicações de luz do fotopolimerizador. RESULTADOS: observou-se redução significativa na sensação dolorosa entre a fase inicial e após as seis sessões de tratamento com laser, porém tal redução, também pode ser observada para o grupo controle, submetido ao placebo. CONCLUSÃO: a terapia com laser de baixa potência de AsGaAl induz redução estatisticamente significante da sensação dolorosa, após cada uma das aplicações, e entre o início e o final do tratamento, embora não tenha havido, diferença estaticamente significante, ao final do tratamento e após a avaliação mediata dos resultados (após 6 semanas entre o grupo tratado (laser e o grupo controle (placebo; dificultando a mensuração real da efetividade do laser e do efeito placebo.
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International Nuclear Information System (INIS)
De Marco, M.; Krása, J.; Margarone, D.; Giuffrida, L.; Vrana, R.; Velyhan, A.; Korn, G.; Weber, S.; Cikhardt, J.; Pfeifer, M.; Krouský, E.; Ullschmied, J.; Ahmed, H.; Borghesi, M.; Kar, S.; Limpouch, J.; Velardi, L.; Side, D. Delle; Nassisi, V.
2016-01-01
A target irradiated with a high power laser pulse, blows off a large amount of charge and as a consequence the target itself becomes a generator of electromagnetic pulses (EMP) owing to high return current flowing to the ground through the target holder. The first measurement of the magnetic field induced by the neutralizing current reaching a value of a few kA was performed with the use of an inductive target probe at the PALS Laser Facility (Cikhardt et al. Rev. Sci. Instrum. 85 (2014) 103507). A full description of EMP generation should contain information on the spatial distribution and temporal variation of the electromagnetic field inside and outside of the interaction chamber. For this reason, we consider the interaction chamber as a resonant cavity in which different modes of EMP oscillate for hundreds of nanoseconds, until the EMP is transmitted outside through the glass windows and EM waves are attenuated. Since the experimental determination of the electromagnetic field distribution is limited by the number of employed antennas, a mapping of the electromagnetic field has to be integrated with numerical simulations. Thus, this work reports on a detailed numerical mapping of the electromagnetic field inside the interaction chamber at the PALS Laser Facility (covering a frequency spectrum from 100 MHz to 3 GHz) using the commercial code COMSOL Multiphysics 5.2. Moreover we carried out a comparison of the EMP generated in the parallelepiped-like interaction chamber used in the Vulcan Petawatt Laser Facility at the Rutherford Appleton Laboratory, against that produced in the spherical interaction chamber of PALS.
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International Nuclear Information System (INIS)
Krupke, W.F.; George, E.V.; Haas, R.A.
1979-01-01
Laser drive systems' performance requirements for fusion reactors are developed following a review of the principles of inertial confinement fusion and of the technical status of fusion research lasers (Nd:glass; CO 2 , iodine). These requirements are analyzed in the context of energy-storing laser media with respect to laser systems design issues: optical damage and breakdown, medium excitation, parasitics and superfluorescence depumping, energy extraction physics, medium optical quality, and gas flow. Three types of energy-storing laser media of potential utility are identified and singled out for detailed review: (1) Group VI atomic lasers, (2) rare earth solid state hybrid lasers, and (3) rare earth molecular vapor lasers. The use of highly-radiative laser media, particularly the rare-gas monohalide excimers, are discussed in the context of short pulse fusion applications. The concept of backward wave Raman pulse compression is considered as an attractive technique for this purpose. The basic physics and device parameters of these four laser systems are reviewed and conceptual designs for high energy laser systems are presented. Preliminary estimates for systems efficiencies are given. (Auth.)
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<em>In Situem> Fabrication of AlN Coating by Reactive Plasma Spraying of Al/AlN Powder
Directory of Open Access Journals (Sweden)
Mohammed Shahien
2011-10-01
Full Text Available Reactive plasma spraying is a promising technology for the <em>in situem> formation of aluminum nitride (AlN coatings. Recently, it became possible to fabricate cubic-AlN-(<em>c>-AlN based coatings through reactive plasma spraying of Al powder in an ambient atmosphere. However, it was difficult to fabricate a coating with high AlN content and suitable thickness due to the coalescence of the Al particles. In this study, the influence of using AlN additive (<em>h>-AlN to increase the AlN content of the coating and improve the reaction process was investigated. The simple mixing of Al and AlN powders was not suitable for fabricating AlN coatings through reactive plasma spraying. However, it was possible to prepare a homogenously mixed, agglomerated and dispersed Al/AlN mixture (which enabled in-flight interaction between the powder and the surrounding plasma by wet-mixing in a planetary mill. Increasing the AlN content in the mixture prevented coalescence and increased the nitride content gradually. Using 30 to 40 wt% AlN was sufficient to fabricate a thick (more than 200 µm AlN coating with high hardness (approximately 1000 Hv. The AlN additive prevented the coalescence of Al metal and enhanced post-deposition nitriding through N2 plasma irradiation by allowing the nitriding species in the plasma to impinge on a larger Al surface area. Using AlN as a feedstock additive was found to be a suitable method for fabricating AlN coatings by reactive plasma spraying. Moreover, the fabricated coatings consist of hexagonal (<em>h>-AlN, <em>c>-AlN (rock-salt and zinc-blend phases and certain oxides: aluminum oxynitride (Al5O6N, cubic sphalerite Al23O27N5 (ALON and Al2O3. The zinc-blend <em>c>-AlN and ALON phases were attributed to the transformation of the <em>h>-AlN feedstock during the reactive plasma spraying. Thus, the zinc-blend<em> cem
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Directory of Open Access Journals (Sweden)
RENATO REZENDE YOUNG BLOOD
2015-06-01
Full Text Available O objetivo deste trabalho foi avaliar a incidência em várias partes da planta e o desenvolvimento da antracnose do caquizeiro causada por Colletotrichum horiinas cultivares Fuyu e Kakimel produzidas sob os sistemas orgânico e convencional, respectivamente, nas safras de 2010/2011 e 2011/2012, em Campina Grande do Sul, Paraná, Brasil. Em cada pomar, 10 plantas foram selecionadas aleatoriamente, e 10 ramos do ano por planta, distribuídos ao redor dacopa, foram marcados para as avaliações de incidência de antracnose em ramos e folhas, a cada 15 dias. A quantificação de frutos caídos com ou sem sintomas da doença foi a cada 15 dias, durante o período de crescimento de frutos até a colheita, relacionada com a produção total. C. horii em flores foi avaliada em campo e também após incubação no laboratório. Infecção latente foi observada em frutos verdes coletados aos 90; 120 e 150 dias após a floração. Em ambas as safras, observou-se a queda de frutos com sintomas de antracnose entre os meses de janeiro e abril. C. horii é capaz de infectar flores, permanecer latente e provocar sintomas de antracnose em frutos imaturos. Frutos colhidos sadios apresentaram sintomas em pós-colheita após a incubação.
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Only lasers can be used for low level laser therapy.
Moskvin, Sergey Vladimirovich
2017-12-01
The question of lasers' exclusivity, as well as the degree of influence of special properties of low-intensity laser illumination (LILI), such as coherence, polarity and monochromaticity, on the effectiveness of low level laser therapy (LLLT) continues to cause arguments. The study analyzes publications from 1973 to 2016, in which laser and conventional light sources are compared, and the following conclusions are drawn. First, there are a lot of publications with incorrect comparison or unfounded statements. Secondly, other sources of light are often meant by LILI without any justification. Thirdly, all studies, in which the comparison is carried out correctly and close parameters of the impact and the model are used, have a firm conclusion that laser light is much more effective. Fourthly, it is uniquely identified that the most important parameter that determines the efficiency of lasers is monochromaticity, i.e., a much narrower spectral width than for all other light sources. Only laser light sources can be used for LLLT! © Author(s) 2017. This article is published with open access by China Medical University.
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EMS applications integration in a SCADA; Integracion de aplicaciones EMS en un SCADA
Energy Technology Data Exchange (ETDEWEB)
Roses, Rodolfo; Colome, D.G.; Orduna, E.; Vega, C. de la; Camisay, G. [Universidad Nacional de San Juan (Argentina). Inst. de Energia Electrica]. E-mail: roses@iee.unsj.edu.ar
2001-07-01
This paper presents the methodology to integrate EMS (Energy Management System) functions in a SCADA system (System Control and Data Acquisition). The implementation methodology of the EMS applications has included the design and database implementation, EMS-SCADA communication, results presentation, logics definition of execution and processing ways. The applications portability characteristics allow integration with different SCADA system with some adaptations on the data communication interface. Thus, a open system has been obtained and implemented successfully in the control center of an Argentine 132 kV network.
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Federal Laboratory Consortium — The Laser Research lab is thecenter for the development of new laser sources, nonlinear optical materials, frequency conversion processes and laser-based sensors for...
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Laser Cutting of Thick Diamond Films Using Low-Power Laser
Energy Technology Data Exchange (ETDEWEB)
Park, Y.J.; Baik, Y.J. [Korea Institute of Science and Technology, Seoul (Korea)
2000-02-01
Laser cutting of thick diamond films is studied rising a low-power(10 W) copper vapor laser. Due to the existence of the saturation depth in laser cutting, thick diamond films are not easily cut by low-power lasers. In this study, we have adopted a low thermal- conductivity underlayer of alumina and a heating stage (up to 500 deg. C in air) to prevent the laser energy from consuming-out and, in turn, enhance the cutting efficiency. Aspect ratio increases twice from 3.5 to 7 when the alumina underlayer used. Adopting a heating stage also increases aspect ratio and more than 10 is obtained at higher temperatures than 400 deg. C. These results show that thick diamond films can be cut, with low-power lasers, simply by modifying the thermal property of underlayer. (author). 13 refs., 5 figs.
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Effect of Calcium and Potassium on Antioxidant System of <em>Vicia fabaem> L. Under Cadmium Stress
Directory of Open Access Journals (Sweden)
Hayssam M. Ali
2012-05-01
Full Text Available Cadmium (Cd in soil poses a major threat to plant growth and productivity. In the present experiment, we studied the effect of calcium (Ca2+ and/or potassium (K+ on the antioxidant system, accumulation of proline (Pro, malondialdehyde (MDA, and content of photosynthetic pigments, cadmium (Cd and nutrients, <em>i.e.>, Ca2+ and K+ in leaf of <em>Vicia faba em>L. (cv. TARA under Cd stress. Plants grown in the presence of Cd exhibited reduced growth traits [root length (RL plant−1, shoot length (SL plant−1, root fresh weight (RFW plant−1, shoot fresh weight (SFW plant−1, root dry weight (RDW plant−1 and shoot dry weight (SDW plant−1] and concentration of Ca2+, K+, Chlorophyll (Chl <em>a> and Chl <em>b em>content, except content of MDA, Cd and (Pro. The antioxidant enzymes [peroxidase (POD and superoxide dismutase (SOD] slightly increased as compared to control under Cd stress. However, a significant improvement was observed in all growth traits and content of Ca2+, K+, Chl <em>a>, Chl <em>b em>,Pro and activity of antioxidant enzymes catalase (CAT, POD and SOD in plants subjected to Ca2+ and/or K+. The maximum alleviating effect was recorded in the plants grown in medium containing Ca2+ and K+ together. This study indicates that the application of Ca2+ and/or K+ had a significant and synergistic effect on plant growth. Also, application of Ca2+ and/or K+ was highly effective against the toxicity of Cd by improving activity of antioxidant enzymes and solute that led to the enhanced plant growth of faba bean plants.
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Laser solenoid: an alternate use of lasers in fusion power
International Nuclear Information System (INIS)
Rose, P.H.
1977-01-01
A unique laser assisted fusion approach is under development at Mathematical Sciences Northwest, Inc. (MSNW). This approach captures one of the most developed aspects of high energy laser technology, the efficient, large, scalable, pulsed electron beam initiated, electric discharge, CO 2 infrared laser. This advanced technology is then combined with the simple geometry of a linear magnetic confinement system. The laser solenoid concept will be described, current work and experimental progress will be discussed, and the technological problems of building such a system will be assessed. Finally a comparison will be made of the technology and economics for the laser solenoid and alternative fusion approaches
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Uso de digital em idosos admitidos em unidade de geriatria de um hospital geral
Directory of Open Access Journals (Sweden)
Cunha Ulisses Gabriel de Vasconcelos
1998-01-01
Full Text Available OBJETVO: Detectar a freqüência da prescrição do digital, assim como as suas indicações, em idosos admitidos em unidade de geriatria de um hospital geral. MÉTODOS: Foram investigados, consecutivamente, 130 pacientes não selecionados, de ambos os sexos (100 mulheres e 30 homens, com idades > ou = 65 (média 80±9 anos. Os pacientes foram avaliados através de exame clínico completo, rotina básica de sangue, radiografia simples de tórax, eletrocardiograma e ecocardiograma Doppler. Baseados na avaliação clínica e exames complementares, o uso do digital foi considerado adequado, questionável ou inadequado. RESULTADOS: Estavam em uso de digital 27,6% dos pacientes. A indicação foi considerada adequada em 36,1%, questionável em 11,1% e inadequada em 52,7%. CONCLUSÃO: Uma alta prevalência de prescrição do digital foi detectada nos idosos admitidos, sendo que a maior parte a adotava por razões consideradas inadequadas ou questionáveis. Devido ao risco aumentado de intoxicação digitálica nessa faixa etária, a droga deveria ser prescrita sob indicações mais criteriosas.
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Estratégias de marketing no fitness: estudo de caso da Vivafit em Portugal e em Singapura
Silva, Sara Durão da
2012-01-01
Mestrado em Gestão do Desporto - Organizações Desportivas Este estudo pretende aferir as diferenças na elaboração das estratégias de marketing de uma empresa da área do fitness, actuante em diferentes países (nomeadamente em países emergentes) ao nível dos Quatro Pilares do Marketing (4 P.): a) produto, b) promoção, c) local, d) preço. Esta pesquisa é num estudo de caso de uma empresa nacional: a Vivafit, comparandose as estratégias utilizadas em Portugal e em Singapura. For...
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Forget, Sébastien
2013-01-01
Organic lasers are broadly tunable coherent sources, potentially compact, convenient and manufactured at low-costs. Appeared in the mid 60’s as solid-state alternatives for liquid dye lasers, they recently gained a new dimension after the demonstration of organic semiconductor lasers in the 90's. More recently, new perspectives appeared at the nanoscale, with organic polariton and surface plasmon lasers. After a brief reminder to laser physics, a first chapter exposes what makes organic solid-state organic lasers specific. The laser architectures used in organic lasers are then reviewed, with a state-of-the-art review of the performances of devices with regard to output power, threshold, lifetime, beam quality etc. A survey of the recent trends in the field is given, highlighting the latest developments with a special focus on the challenges remaining for achieving direct electrical pumping of organic semiconductor lasers. A last chapter covers the applications of organic solid-state lasers.
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Zory, Jr, Peter S; Kelley, Paul
1993-01-01
This book provides the information necessary for the reader to achieve a thorough understanding of all aspects of QW lasers - from the basic mechanism of optical gain, through the current technolgoical state of the art, to the future technologies of quantum wires and quantum dots. In view of the growing importance of QW lasers, this book should be read by all those with an active interest in laser science and technology, from the advanced student to the experienced laser scientist.* The first comprehensive book-length treatment of quantum well lasers* Provides a detailed treatment
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CSIR Research Space (South Africa)
Michaelis, MM
2008-04-01
Full Text Available cube, laser beam reflectors, placed on the Moon half a century ago. These early achievements will soon be followed by a plethora of experiments involving lasers in low earth orbit (LEO) or at Lagrange points. And not much later, laser communications... will stretch out as far as Mars and beyond. One important low Earth orbit (LEO) application is the removal of space debris by Earth based or LEO relayed lasers as promoted by Phipps et al.3. Another is military communication. The prominent L1 laser space...
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Bleaching Dengan Teknologi Laser
Eliwaty
2008-01-01
Penulisan tentang bleaching dengan laser dimaksudkan untuk menambah wawasan serta pengetahuan dari pembaca di bidang kedokteran gigi. Macam-macam laser yang dipergunakan dalam bleaching yaitu argon, CO2 serta dioda laser. Contoh merek produk laser yaitu Blulaze, Dentcure untuk argonlaser, Novapulse untuk C02 serta Opus 5 untuk dioda laser. Laser bleaching hasilnya dapat dicapai dalam satu kunjungan saja, cepat, efisien namun biayanya relatif mahal, dapat menimbulkan burn, sensitivitas se...
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Energy Technology Data Exchange (ETDEWEB)
Kuwabara, M.; Bando, N. (Asahi Glass Co. Ltd., Tokyo (Japan))
1991-12-25
A semiconductor laser (LD) excited solid state laser using an LD as an excited light source is under discussion for its practical applications to measurements, processing, communications, office automation, and medical areas. This paper describes the discussions given on the short pulse transmission using AOQ switching elements in the LD excited solid state laser with a long wave length band (1.3{mu}m), which is expected of its application in the communications and measurements area. Based on a possibility of raising a measurements resolution by making the pluses in the LD excited solid state laser, and experiments were performed using Nd:YLF as a laser host. as a results, it was found that the smaller the effective mode volume V {sub eff},the smaller the pulse width, and that the ratio of number of initial inversion distribution (N{sub i}/N{sub t}), an important parameter to determine pulse widths, can be obtained from the ratio of the LD exciting light to the input power (P{sub in}/P{sub t}). 7 refs., 14 figs., 2 tabs.
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Wavelength sweepable laser source
DEFF Research Database (Denmark)
2014-01-01
Wavelength sweepable laser source is disclosed, wherein the laser source is a semiconductor laser source adapted for generating laser light at a lasing wavelength. The laser source comprises a substrate, a first reflector, and a second reflector. The first and second reflector together defines...... and having a rest position, the second reflector and suspension together defining a microelectromechanical MEMS oscillator. The MEMS oscillator has a resonance frequency and is adapted for oscillating the second reflector on either side of the rest position.; The laser source further comprises electrical...... connections adapted for applying an electric field to the MEMS oscillator. Furthermore, a laser source system and a method of use of the laser source are disclosed....
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Mathematical modeling of a photovoltaic-laser energy converter for iodine laser radiation
Walker, Gilbert H.; Heinbockel, John H.
1987-01-01
Space-based laser power systems will require converters to change laser radiation into electricity. Vertical junction photovoltaic converters are promising devices for this use. A promising laser for the laser power station is the t-C4F9I laser which emits radiation at a wavelength of 1.315 microns. This paper describes the results of mathematical modeling of a photovoltaic-laser energy converter for use with this laser. The material for this photovoltaic converter is Ga(53)In(47)As which has a bandgap energy of 0.94 eV, slightly below the energy of the laser photons (0.943 eV). Results of a study optimizing the converter parameters are presented. Calculated efficiency for a 1000 vertical junction converter is 42.5 percent at a power density of 1 x 10 to the 3d power w/sq cm.
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Laser Materials and Laser Spectroscopy - A Satellite Meeting of IQEC '88
Wang, Zhijiang; Zhang, Zhiming
1989-03-01
The Table of Contents for the book is as follows: * Laser Materials * Laser Site Spectroscopy of Transition Metal Ions in Glass * Spectroscopy of Chromium Doped Tunable Laser Materials * Spectroscopic Properties of Nd3+ Ions in LaMgAl11O19 Crystal * Spectral Study and 2.938 μm Laser Emission of Er3+ in the Y3Al5O12 Crystal * Raman-infrared Spectra and Radiationless Relaxation of Laser Crystal NdAl3(BO3)4 * A Study on HB and FLN in BaFCl0.5Br0.5:Sm2+ at 77K * Pair-pumped Upconversion Solid State Lasers * CW Upconversion Laser Action in Neodymium and Erbium doped Solids * Ultra-high Sensitive Upconversion Fluorescence of YbF3 Doped with Trace Tm3+ and Er3+ * The Growth and Properties of NYAB and EYAB Multifunctional Crystal * Study on Fluorescence and Laser Light of Er3+ in Glass * Growth and Properties of Single Crystal Fibers for Laser Materials * A Study on the Quality of Sapphire, Ruby and Ti3+ Doped Sapphire Grown by Temperature Gradient Technique (TGT) and Czochralski Technique (CZ) * The Measurement of Output Property of Ti3+ Al2O3 Laser Crystal * An Xα Study of the Laser Crystal MgF2 : V2+ * Q-switched NAB Laser * Miniature YAG Lasers * Study of High Efficiency {LiF}:{F}^-_2 Color Center Crystals * Study on the Formation Conditions and Optical Properties of (F2+)H Color Center in NaCl:OH- Crystals * Novel Spectroscopic Properties of {LiF}:{F}^+_3 - {F}_2 Mixed Color Centers Laser Crystals * Terraced Substrate Visible GaAlAs Semiconductor Lasers with a Large Optical Cavity * The Temperature Dependence of Gain Spectra, Threshold Current and Auger Recombination in InGaAsP-InP Double Heterojunction Laser diode * Time-resolved Photoluminescence and Energy Transfer of Bound Excitons in GaP:N Crystals * Optical Limiting with Semiconductors * A Critical Review of High-efficiency Crystals for Tunable Lasers * Parametric Scattering in β - BaB2O4 Crystal Induced by Picosecond Pulses * Generation of Picosecond Pulses at 193 nm by Frequency Mixing in β - BaB2O4
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Ultraviolet laser transverse profile shaping for improving x-ray free electron laser performance
International Nuclear Information System (INIS)
Li, S.; Alverson, S.; Bohler, D.; Egger, A.; Fry, A.
2017-01-01
The photocathode rf gun is one of the most critical components in x-ray free electron lasers. The drive laser strikes the photocathode surface, which emits electrons with properties that depend on the shape of the drive laser. Most free electron lasers use photocathodes with work function in the ultraviolet, a wavelength where direct laser manipulation becomes challenging. In this paper, we present a novel application of a digital micromirror device (DMD) for the 253 nm drive laser at the Linear Coherent Light Source. Laser profile shaping is accomplished through an iterative algorithm that takes into account shaping error and efficiency. Next, we use laser shaping to control the X-ray laser output via an online optimizer, which shows improvement in FEL pulse energy. Lastly, as a preparation for electron beam shaping, we use the DMD to measure the photocathode quantum efficiency across cathode surface with an averaged laser rms spot size of 59 μm. In conclusion, our experiments demonstrate promising outlook of using DMD to shape ultraviolet lasers for photocathode rf guns with various applications.
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Ultraviolet laser transverse profile shaping for improving x-ray free electron laser performance
Li, S.; Alverson, S.; Bohler, D.; Egger, A.; Fry, A.; Gilevich, S.; Huang, Z.; Miahnahri, A.; Ratner, D.; Robinson, J.; Zhou, F.
2017-08-01
The photocathode rf gun is one of the most critical components in x-ray free electron lasers. The drive laser strikes the photocathode surface, which emits electrons with properties that depend on the shape of the drive laser. Most free electron lasers use photocathodes with work function in the ultraviolet, a wavelength where direct laser manipulation becomes challenging. In this paper, we present a novel application of a digital micromirror device (DMD) for the 253 nm drive laser at the Linear Coherent Light Source. Laser profile shaping is accomplished through an iterative algorithm that takes into account shaping error and efficiency. Next, we use laser shaping to control the X-ray laser output via an online optimizer, which shows improvement in FEL pulse energy. Lastly, as a preparation for electron beam shaping, we use the DMD to measure the photocathode quantum efficiency across cathode surface with an averaged laser rms spot size of 59 μ m . Our experiments demonstrate promising outlook of using DMD to shape ultraviolet lasers for photocathode rf guns with various applications.
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Directory of Open Access Journals (Sweden)
Hawa Z.E. Jaafar
2012-05-01
Full Text Available A split plot 3 × 3 experiment was designed to examine the impact of three concentrations of CO2 (400, 800 and 1,200 µmol·mol−1 on the phenolic and flavonoid compound profiles, phenylalanine ammonia lyase (PAL and antioxidant activity in three varieties of <em>Labisia pumilaem> Benth. (var. <em>alata,
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International Nuclear Information System (INIS)
Gorbatenko, A A; Revina, E I
2015-01-01
The review is devoted to the major advances in laser sampling. The advantages and drawbacks of the technique are considered. Specific features of combinations of laser sampling with various instrumental analytical methods, primarily inductively coupled plasma mass spectrometry, are discussed. Examples of practical implementation of hybrid methods involving laser sampling as well as corresponding analytical characteristics are presented. The bibliography includes 78 references
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Studies on corrosion protection of laser hybrid welded AISI 316 by laser remelting
DEFF Research Database (Denmark)
Olsen, Flemming Ove; Ambat, Rajan; Rasmussen, A.J.
2005-01-01
laser surface melting on microstructure and corrosion behaviour of AISI 316L welds. Welding and laser treatment parameters were varied. General corrosion behaviour of the weld and laser treated surface was characterised using a gel visualization test. The local electrochemistry of the weld and laser......Unlike in autogenous laser welding, hybrid laser welding of stainless steel could introduce grain boundary carbides due to low cooling rates. Formation of grain boundary carbides leads to reduced corrosion properties. Studies have initially been carried out on hybrid laser welding and subsequent...... treated surface was investigated using a novel micro electrochemical technique with a tip resolution of ~1 mm. Results show that hybrid laser welding of 316L has increased corrosion susceptibility probably as a result of grain boundary carbide formation. However a suitable post laser treatment could...
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Sentis, Marc L.; Delaporte, Philippe C.; Marine, Wladimir; Uteza, Olivier P.
2000-04-01
The application of excimer laser ablation process to the decontamination of radioactive surfaces is discussed. This technology is very attractive because it allows to efficiently remove the contaminated particles without secondary waste production. To demonstrate the capability of such technology to efficiently decontaminate large area, we studied and developed a prototype which include a XeCl laser, an optical fiber delivery system and an ablated particles collection cell. The main physical processes taking place during UV laser ablation will be explained. The influence of laser wavelength, pulse duration and absorption coefficient of material will be discussed. Special studies have been performed to understand the processes which limit the transmission of high average power excimer laser through optical fiber, and to determine the laser conditions to optimize the value of this transmission. An in-situ spectroscopic analysis of laser ablation plasma allows the real time control of the decontamination. The results obtained for painting or metallic oxides removal from stainless steel surfaces will be presented.
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Efficient Ho:YLF laser pumped by a Tm:fiber laser
CSIR Research Space (South Africa)
Koen, W
2013-10-01
Full Text Available A thulium fiber laser pumped Ho:YLF laser delivering 45.1 W in a near diffraction limited beam when pumped with 84.7 W is demonstrated. The optical-to-optical efficiency of 53 % compares favorably with similar Ho:YAG lasers....
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Laser Safety Evaluation of the MILES and Mini MILES Laser Emitting Components; TOPICAL
International Nuclear Information System (INIS)
AUGUSTONI, ARNOLD L.
2002-01-01
Laser safety evaluation and output emission measurements were performed (during October and November 2001) on SNL MILES and Mini MILES laser emitting components. The purpose, to verify that these components, not only meet the Class 1 (eye safe) laser hazard criteria of the CDRH Compliance Guide for Laser Products and 21 CFR 1040 Laser Product Performance Standard; but also meet the more stringent ANSI Std. z136.1-2000 Safe Use of Lasers conditions for Class 1 lasers that govern SNL laser operations. The results of these measurements confirmed that all of the Small Arms Laser Transmitters, as currently set (''as is''), meet the Class 1 criteria. Several of the Mini MILES Small Arms Transmitters did not. These were modified and re-tested and now meet the Class 1 laser hazard criteria. All but one System Controllers (hand held and rifle stock) met class 1 criteria for single trigger pulls and all presented Class 3a laser hazard levels if the trigger is held (continuous emission) for more than 5 seconds on a single point target. All units were Class 3a for ''aided'' viewing. These units were modified and re-tested and now meet the Class 1 hazard criteria for both ''aided'' as well as ''unaided'' viewing. All the Claymore Mine laser emitters tested are laser hazard Class 1 for both ''aided'' as well as ''unaided'' viewing
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International Nuclear Information System (INIS)
Sun, Wenbo; Hu, Yongxiang; Weimer, Carl; Ayers, Kirk; Baize, Rosemary R.; Lee, Tsengdar
2017-01-01
Electromagnetic (EM) beams with orbital angular momentum (OAM) may have great potential applications in communication technology and in remote sensing of the Earth-atmosphere system and outer planets. Study of their interaction with optical lenses and dielectric or metallic objects, or scattering of them by particles in the Earth-atmosphere system, is a necessary step to explore the advantage of the OAM EM beams. In this study, the 3-dimensional (3D) scattered-field (SF) finite-difference time domain (FDTD) technique with the convolutional perfectly matched layer (CPML) absorbing boundary conditions (ABC) is applied to calculate the scattering of the purely azimuthal (the radial mode number is assumed to be zero) Laguerre–Gaussian (LG) beams with the OAM by dielectric particles. We found that for OAM beam's interaction with dielectric particles, the forward-scattering peak in the conventional phase function (P11) disappears, and light scattering peak occurs at a scattering angle of ~15° to 45°. The disappearance of forward-scattering peak means that, in laser communications most of the particle-scattered noise cannot enter the receiver, thus the received light is optimally the original OAM-encoded signal. This feature of the OAM beam also implies that in lidar remote sensing of the atmospheric particulates, most of the multiple-scattering energy will be off lidar sensors, and this may result in an accurate profiling of particle layers in the atmosphere or in the oceans by lidar, or even in the ground when a ground penetration radar (GPR) with the OAM is applied. This far-field characteristics of the scattered OAM light also imply that the optical theorem, which is derived from plane-parallel wave scattering case and relates the forward scattering amplitude to the total cross section of the scatterer, is invalid for the scattering of OAM beams by dielectric particles. - Highlights: • Scattering of orbital angular momentum (OAM) laser beam by dielectric
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Estudo sobre variações em métodos de análise de compostos fibrosos em alimentos
Gomes, Daiany Iris
2012-01-01
A presente tese foi elaborada com base quatro artigos científicos. No primeiro artigo objetivou-se avaliar os teores de fibra insolúvel em detergente neutro (FDN) e de fibra insolúvel em detergente ácido (FDA) em alimentos volumosos e concentrados e em fezes bovinas utilizando-se sacos filtrantes sob dois diferentes ambientes físicos de extração: pressurizado e não pressurizado. Vinte amostras de cada material foram utilizadas. Os conteúdos obtidos em diferentes ambientes foram comparados po...
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Laser ablation principles and applications
1994-01-01
Laser Ablation provides a broad picture of the current understanding of laser ablation and its many applications, from the views of key contributors to the field. Discussed are in detail the electronic processes in laser ablation of semiconductors and insulators, the post-ionization of laser-desorbed biomolecules, Fourier-transform mass spectroscopy, the interaction of laser radiation with organic polymers, laser ablation and optical surface damage, laser desorption/ablation with laser detection, and laser ablation of superconducting thin films.
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International Nuclear Information System (INIS)
Stark, E.E. Jr.
1978-01-01
The basic concept of laser fusion is described, with a set of requirements on the laser system. Systems and applications concepts are presented and discussed. The CO 2 laser's characteristics and advantages for laser fusion are described. Finally, technological issues in the development of CO 2 laser systems for fusion applications are discussed
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Laser dynamics of asynchronous rational harmonic mode-locked fiber soliton lasers
International Nuclear Information System (INIS)
Jyu, Siao-Shan; Jiang, Guo-Hao; Lai, Yinchieh
2013-01-01
Laser dynamics of asynchronous rational harmonic mode-locked (ARHM) fiber soliton lasers are investigated in detail. In particular, based on the unique laser dynamics of asynchronous mode-locking, we have developed a new method for determining the effective active modulation strength in situ for ARHM lasers. By measuring the magnitudes of the slowly oscillating pulse timing position and central frequency, the effective phase modulation strength at the multiplication frequency of rational harmonic mode-locking can be accurately inferred. The method can be a very useful tool for developing ARHM fiber lasers. (paper)
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Fatores de risco cardiovascular em alcoolistas em tratamento
Directory of Open Access Journals (Sweden)
Mayla Cardoso Fernandes Toffolo
2013-06-01
Full Text Available OBJETIVO: Avaliar a presença de fatores de risco cardiovascular, com ênfase na hipertensão e na adiposidade corporal, em alcoolistas abstinentes ou não abstinentes em tratamento. MÉTODO: Trata-se de um estudo transversal com 65 pacientes alcoolistas em tratamento no CAP-Sad. O grau de dependência do álcool foi avaliado pelo SADD (Short Alcohol Dependence Data e o uso de outras drogas, pelo ASSIST (Alcohol Smoking and Substance Involvement Screening Test. Foram avaliados o perfil bioquímico e o antropométrico dos usuários. RESULTADOS: Participaram do estudo 42 homens e 23 mulheres. A maioria dos participantes (67,74% apresentou dependência alcoólica grave, com uso de álcool associado principalmente a cigarro (66,15%. A média da circunferência da cintura (CC foi significativamente maior entre os abstinentes, em comparação aos não abstinentes (AB: 88,15 ± 15,95 x NA: 81,04 ± 9,86; p = 0,03. Pacientes abstinentes há mais tempo tiveram maior sobrepeso/obesidade e adiposidade abdominal (CC do que os não abstinentes e abstinentes recentes, com razão de chances de 5,25. Os abstinentes apresentaram razão de chances de 3,38 para %GC acima da média, independente do tempo de abstinência. CONCLUSÃO: Pacientes alcoolistas abstinentes apresentam mais sobrepeso/ obesidade, adiposidade corporal (%GC e abdominal (CC do que os não abstinentes. É importante o acompanhamento multiprofissional no tratamento de alcoolistas com abordagem para fatores de risco cardiovasculares, principalmente evitando o ganho de peso.
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Directory of Open Access Journals (Sweden)
Francesco Maria Angelici
1992-07-01
Full Text Available Abstract Two sightings of Common dolphin <em>Delphinus delphisem> in the Channel of Otranto are reported, and the status of this species in the Mediterranean Sea is briefly discussed. Riassunto Sono riportati due avvistamenti di Delfino comune <em>Delphinus delphisem> nel Canale d'Otranto, lungo la costa greca e quella italiana. Viene inoltre brevemente commentata la frequenza degli avvistamenti e degli spiaggiamenti di tale specie nel Mar Mediterraneo.
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Radiological protection against lasers
Energy Technology Data Exchange (ETDEWEB)
Ballereau, P
1974-04-01
A brief description of the biological effects of laser beams is followed by a review of the factors involved in eye and skin damage (factors linked with the nature of lasers and those linked with the organ affected) and a discussion of the problems involved in the determination of threshold exposure levels. Preventive measures are recommended, according to the type of laser (high-energy pulse laser, continuous laser, gas laser). No legislation on the subject exists in France or in Europe. Types of lasers marketed, threshold exposure levels for eye and skin, variations of admissible exposure levels according to wavelength, etc. are presented in tabular form. Nomogram for determination of safe distance for direct vision of a laser is included.
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Laser-tissue interaction in tattoo removal by q-switched lasers.
Barua, Shyamanta
2015-01-01
Q-switched (QS) lasers are widely considered the gold standard for tattoo removal, with excellent clinical results, impressive predictability, and a good safety profile. The generation of giant pulses by the method of Q-switching is responsible for the unique laser-tissue interaction that is seen in tattoo removal by QS lasers. The QS lasers work by impaction and dissolution of the tattoo pigments. Mechanical fragmentation of the tattoo pigments encased in intracellular lamellated organelles followed by their phagocytosis by macrophages is thought to be the major event in the clearance of pigments by QS lasers. A few novel techniques have been tried in recent times to hasten the clearance of tattoo pigments.
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Sher, Mark H.; Macklin, John J.; Harris, Stephen E.
1989-09-26
A traveling-wave, laser-produced-plasma, energy source used to obtain single-pass gain saturation of a photoionization pumped laser. A cylindrical lens is used to focus a pump laser beam to a long line on a target. Grooves are cut in the target to present a surface near normal to the incident beam and to reduce the area, and hence increase the intensity and efficiency, of plasma formation.
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Associativismo negro em terras sulinas: das irmandades aos clubes para negros em Pelotas (1820-1943
Directory of Open Access Journals (Sweden)
Fernanda Oliveira da Silva
2011-12-01
Full Text Available O artigo analisa as associações negras pelotenses que permitiram a constituição de uma identidade negra positiva percebida em relação direta com o contexto relacional vivenciado em âmbito nacional e internacional. Destacamos ainda a busca por um entrelaçamento entre diferentes associações tendo como ponto em comum a identificação racial mediada pela busca por uma posição social diferenciada. Diretamente vinculado ao período do pós-Abolição almejava-se a cidadania em uma sociedade ainda muito preconceituosa racialmente. A delimitação espacial focaliza o estudo na cidade de Pelotas, localizada no extremo sul do Rio Grande do Sul, entre os anos de 1820 a 1943. Tem inicio com a criação da primeira irmandade negra em 1820. Dentre as associações destacamos o surgimento dos clubes sociais negros (1917-1931 e suas atividades em conjunto, com ênfase para o surgimento da Frente Negra Pelotense (1933 e a busca por uma identidade racial que fosse comungada por todo o grupo negro local.
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Vitamina A em dieta de juvenis de pacu cultivados em tanques-rede
Directory of Open Access Journals (Sweden)
Arcangelo Augusto Signor
2013-08-01
Full Text Available O objetivo deste trabalho foi avaliar o efeito da suplementação de vitamina A na alimentação de juvenis de pacu cultivados em tanques-rede. Foram utilizados 2.000 peixes, com peso inicial médio de 66,93±15,03 g, distribuídos em delineamento inteiramente casualizado, em 20 tanques-rede de 5,0 m³, com cinco tratamentos e quatro repetições. As rações foram formuladas com 0, 3.000, 6.000, 9.000 e 12.000 UI de vitamina A por quilograma de dieta, por meio da suplementação com acetato de retinol. O arraçoamento foi realizado às 8:30, 13:30 e 17:30 h, até a saciedade aparente dos animais. Não foram observadas diferenças quanto aos parâmetros de desempenho produtivo, rendimento e composição química da carcaça, e aos parâmetros hematológicos e lipídios no fígado dos peixes que foram alimentados com diferentes níveis de vitamina A. A suplementação de vitamina A em dietas para juvenis de pacu criados em tanques-rede não influencia o desempenho produtivo dos peixes.
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5W intracavity frequency-doubled green laser for laser projection
Yan, Boxia; Bi, Yong; Li, Shu; Wang, Dongdong; Wang, Dongzhou; Qi, Yan; Fang, Tao
2014-11-01
High power green laser has many applications such as high brightness laser projection and large screen laser theater. A compact and high power green-light source has been developed in diode-pumped solid-state laser based on MgO doped periodically poled LiNbO3 (MgO:PPLN). 5W fiber coupled green laser is achieved by dual path Nd:YVO4/MgO:PPLN intra-cacity frequency-doubled. Single green laser maximum power 2.8W at 532nm is obtained by a 5.5W LD pumped, MgO:PPLN dimensions is 5mm(width)×1mm(thickness)×2mm(length), and the optical to optical conversion efficiency is 51%. The second LD series connected with the one LD, the second path green laser is obtained using the same method. Then the second path light overlap with the first path by the reflection mirrors, then couple into the fiber with a focus mirror. Dual of LD, Nd:YVO4, MgO:PPLN are placed on the same heat sink using a TEC cooling, the operating temperature bandwidth is about 12°C and the stablity is 5% in 96h. A 50×50×17mm3 laser module which generated continuous-wave 5 W green light with high efficiency and width temperature range is demonstrated.
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International Nuclear Information System (INIS)
Zidan, M. D.; Al-Awad, F.; Alsous, M. B.
2005-01-01
In this work, we describe the design of the Raman laser pumped by Frequency doubled Nd-YAG laser (λ=532 nm) to generate new laser wavelengths by shifting the frequency of the Nd-YAG laser to Stokes region (λ 1 =683 nm, λ 2 =953.6 nm, λ 3 =1579.5 nm) and Antistokes region (λ ' 1 =435 nm, λ ' 2 =369.9 nm, λ ' 3=319.8 nm). Laser resonator has been designed to increase the laser gain. It consists of two mirrors, the back mirror transmits the pump laser beam (λ=532 nm) through the Raman tube and reflects all other generated Raman laser lines. Four special front mirrors were made to be used for the four laser lines λ 1 =683 nm, λ 2 =953.6 nm and λ ' 1 = 435 nm, λ ' 2 =369.9 nm. The output energy for the lines υ 1 s, υ 2 s, υ 1 as,υ 2 as was measured. The output energy of the Raman laser was characterized for different H 2 pressure inside the tube. (Author)
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Directory of Open Access Journals (Sweden)
Roger I. Vargas
2012-08-01
Full Text Available <em>Bactrocera> fruit fly species are economically important throughout the Pacific. The USDA, ARS U.S. Pacific Basin Agricultural Research Center has been a world leader in promoting biological control of <em>Bactrocera> spp. that includes classical, augmentative, conservation and IPM approaches. In Hawaii, establishment of <em>Bactrocera> <em>cucurbitae> (Coquillett in 1895 resulted in the introduction of the most successful parasitoid, <em>Psyttalia> <em>fletcheri> (Silvestri; similarly, establishment of <em>Bactrocera> <em>dorsalis> (Hendel in 1945 resulted in the introduction of 32 natural enemies of which <em>Fopius> <em>arisanus> (Sonan, <em>Diachasmimorpha> <em>longicaudata> (Ashmead and <em>Fopius> <em>vandenboschi> (Fullaway were most successful. Hawaii has also been a source of parasitoids for fruit fly control throughout the Pacific region including Australia, Pacific Island Nations, Central and South America, not only for <em>Bactrocera> spp. but also for <em>Ceratitis> and <em>Anastrepha> spp. Most recently, in 2002, <em>F.> <em>arisanus> was introduced into French Polynesia where <em>B.> <em>dorsalis> had invaded in 1996. Establishment of <em>D.> <em>longicaudata> into the new world has been important to augmentative biological control releases against <em>Anastrepha> spp. With the rapid expansion of airline travel and global trade there has been an alarming spread of <em>Bactrocera> spp. into new areas of the world (<em>i.e.>, South America and Africa. Results of studies in Hawaii and French Polynesia, support parasitoid introductions into South America and Africa, where <em>B.> <em>carambolae> and <em>B.> <em>invadens>, respectively, have become established. In addition, <em>P.> <em>fletcheri> is a candidate for biological control of <em>B.> <em>cucurbitae> in Africa. We review past and more
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Mulheres em idade fértil: causas de internação em Unidade de Terapia Intensiva e resultados
Cátia Millene Dell Agnolo; Angela Andréia França Gravena; Tiara Cristina Romeiro-Lopes; Sheila Cristina Rocha-Brischiliari; Maria Dalva de Barros Carvalho; Sandra Marisa Pelloso
2014-01-01
Introdução: Pacientes obstétricas representam uma fração significativa das admissões em unidades de cuidado intensivo e consistem em um desafio para a equipe. Objetivo: Analisar as principais causas de internação e morte materna de mulheres em idade fértil ocorridas em unidades de terapia intensiva de hospitais de um município do Noroeste do Paraná, Sul do Brasil. Métodos: Estudo exploratório, descritivo, retrospectivo, realizado com mulheres em idade fértil (10 a 49 anos) internadas em três ...
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Directory of Open Access Journals (Sweden)
Roberto Toffoli
2006-09-01
Full Text Available Riassunto Ritrovamento del Vespertilio di Brandt <em>Myotis brandtiiem> (Eversmann, 1845 in Piemonte (Chiroptera, Vespertilionidae Viene riportata la cattura con mist-net di 5 maschi adulti di Vespertilio di Brandt <em>Myotis brandtiiem>, nell’agosto 2005, nei pressi dell’abitato di Devero (Baceno, VB, a 1827 metri d’altitudine, nel Parco Naturale Alpe Veglia e Alpe Devero. Tale dato rappresenta la prima segnalazione certa della specie in Piemonte. L’identificazione è stata effettuata sulla base delle caratteristiche dentarie e del pene. Sono fornite indicazioni sulle caratteristiche dei segnali di ecolocalizzazione ottenuti dopo il rilascio degli individui.
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Development of Cr,Nd:GSGG laser as a pumping source of Ti:sapphire laser
International Nuclear Information System (INIS)
Tamura, Koji; Arisawa, Takashi
1999-08-01
Since efficiency of Cr,Nd doped gadolinium scandium gallium garnet (GSGG) laser is in principle higher than that of Nd:YAG laser, it can be a highly efficient pumping source for Ti:sapphire laser. We have made GSGG laser, and measured its oscillation properties. It was two times more efficient than Nd:YAG laser at free running mode operation. At Q-switched mode operation, fundamental output of 50 mJ and second harmonics output of 8 mJ were obtained. The developed laser had appropriate spatial profile, temporal duration, long time stability for solid laser pumping. Ti:sapphire laser oscillation was achieved by the second harmonics of GSGG laser. (author)
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International Nuclear Information System (INIS)
Matthews, D.L.; Rosen, M.D.
1988-01-01
One of the elusive dreams of laser physicists has been the development of an x-ray laser. After 25 years of waiting, the x-ray laser has at last entered the scientific scene, although those now in operation are still laboratory prototypes. They produce soft x rays down to about five nanometers. X-ray lasers retain the usual characteristics of their optical counterparts: a very tight beam, spatial and temporal coherence, and extreme brightness. Present x-ray lasers are nearly 100 times brighter that the next most powerful x-ray source in the world: the electron synchrotron. Although Lawrence Livermore National Laboratory (LLNL) is widely known for its hard-x-ray laser program which has potential applications in the Strategic Defense Initiative, the soft x-ray lasers have no direct military applications. These lasers, and the scientific tools that result from their development, may one day have a place in the design and diagnosis of both laser fusion and hard x-ray lasers. The soft x-ray lasers now in operation at the LLNL have shown great promise but are still in the primitive state. Once x-ray lasers become reliable, efficient, and economical, they will have several important applications. Chief among them might be the creation of holograms of microscopic biological structures too small to be investigated with visible light. 5 figs
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Directory of Open Access Journals (Sweden)
Cristina Mansur
2004-04-01
Full Text Available Os autores apresentam três casos de transplante de cabelo em que foram feitas incisões receptoras mistas: orifício com vaporização com laser de CO2 nos quais se adicionou uma incisão lateral a frio. Essa incisão lateral facilita a introdução dos microenxertos por permitir a saída do ar e melhora sua fixação por conferir elasticidade ao orifício. Os pacientes foram previamente betabloqueados para evitar o efeito beta da adrenalina.The authors present three hair transplantation cases in which the receptor incisions were made in a variety of ways: CO2 laser vaporization orifices, in addition to which a lateral cold incision was performed. This lateral incision makes it easier to introduce micrografts by allowing air to be released and improves the fixation of the grafts by giving some elasticity to the orifice. The patients were previously beta blocked to prevent the beta-adrenergic action of epinefrin.
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Doenca renal policistica autossomica dominante em pacientes em hemodialise no sul do Brasil
Directory of Open Access Journals (Sweden)
Everton Fernando Alves
2014-03-01
Full Text Available Introdução: A doença renal policística autossômica dominante é a enfermidade renal hereditária mais comum em seres humanos. Objetivo: Analisar a prevalência, características clínicas e laboratoriais de pacientes com rins policísticos e relacionar as manifestações da doença por gênero. Métodos: Trata-se de um estudo observacional e retrospectivo. Foram revisados todos os prontuários médicos de pacientes com rins policísticos admitidos para hemodiálise entre 1995 e 2012, em quatro centros que atendem a área de abrangência da 15ª regional de saúde do Paraná, Brasil. Resultados: Fizeram parte do estudo 48 pacientes com rins policísticos, causa primária da doença renal crônica (DRC estágio 5. A prevalência da doença foi de um em 10.912 habitantes. A média de idade de ingresso na hemodiálise (50,7 anos e o tempo de seguimento em hemodiálise até o transplante (36,5 meses foi menor nos homens. A hipertensão arterial foi o diagnóstico mais frequente em 73% dos pacientes, com predominância em mulheres (51,4%. O cisto hepático foi a manifestação extrarrenal mais frequente nos homens (60,0%. Foram a óbito 10,4% dos pacientes que faziam uso de hemodiálise, sendo 60% de homens. A classe de droga anti-hipertensiva mais utilizada foi a que atua no sistema renina-angiotensina, com maior frequência de uso nas mulheres (53,3%. A ureia pós-diálise foi significativamente maior em homens. Conclusão: A prevalência da doença é baixa entre pacientes em hemodiálise no sul do Brasil. As diferenças observadas entre os gêneros, com exceção da ureia pós, não foram significantes. Os dados encontrados são diferentes dos reportados na América do Norte e Europa.
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Directory of Open Access Journals (Sweden)
Ana Lúcia Rezende de Souza
2010-03-01
Full Text Available Em seis animais adultos Myrmecophaga tridactyla estudou-se o modelo de suprimento sanguíneo do intestino grosso, que é dependente das artérias mesentérica cranial (AMCr e caudal (AMC. Os espécimes coletados conforme as normas do IBAMA (Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis foram perfundidos com água (40 C, injetados com látex corado, fixados em formol e conservados em solução alcoólica (50%. O mesocólon está disposto na linha sagital mediana e fixa o intestino grosso à parede dorsal do abdome. Derivaram da AMC: a artéria retal cranial, sete a 14 artérias cólicas e uma ou duas artérias ileocólicas, que apresentaram anastomoses de irrigação com a AMCr. A AMC finaliza-se na borda mesocólica das alças intestinais, emitindo ramos cólicos retos a partir das arcadas justacólicas, que penetram na intimidade da musculatura longitudinal. Ao longo do trajeto da AMC foram observadas ilhas arteriais, e a região ileocólica apresentou maior densidade vascular.This research aimed to study the model of large intestine blood supply, which is dependent on the cranial mesenteric artery (AMCr and caudal mesenteric artery (AMC, in six adults of Myrmecophaga tridactyla. The specimens were collected in accordance with the IBAMA standards (Brazilian Institute of the Environment and were perfused with water (40 C, injected with colored latex, fixed in formaldehyde and preserved in alcohol solution (50%. The mesocolon is positioned in the median sagittal line and fixes the large intestine to the dorsal wall of the abdomen. The following is derived from the AMC: the cranial rectal artery, from 7 to 14 colic arteries and one or two ileocolic arteries, which present irrigation anastomosis with AMCr. The AMC finishes at the mesocolic edge of the bowel loop, generating straight colic branches from juxtacolic arcades, which penetrate the intimacy of longitudinal muscles. Arterial islands were observed along the AMC
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History and principle of lasers
International Nuclear Information System (INIS)
Townes, Ch.H.; Schwob, C.; Julien, J.; Forget, S.; Robert-Philip, I.; Balcou, Ph.
2010-01-01
In the first article C.H. Townes, the inventor of the maser, describes the work and ideas that led to the invention of the laser. The second article explains how a laser operate and the third article reviews the main different types of laser: solid lasers, gas lasers, diode lasers and dye lasers
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Carlos Roberto Padovani; Claudio Luiz Bock
2000-01-01
Este trabalho apresenta uma revisão bibliográfica sobre a reprodução artificial, incubação e alevinagem de pacu em viveiros de terra. As técnicas de propagação artificial possibilitam o suprimento de ovos para uma grande variedade de peixes destinados à criação em viveiros e outros corpos de água confinados, bem como para sistemas superintensivos. Essas técnicas tornaram igualmente possível introduzir várias espécies importantes de peixes em áreas geográficas separadas. Além disso, permitem a...
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Laser Safety and Hazard Analysis for the Trailer (B70) Based AURA Laser System
International Nuclear Information System (INIS)
AUGUSTONI, ARNOLD L.
2003-01-01
A laser safety and hazard analysis was performed for the AURA laser system based on the 2000 version of the American National Standards Institute's (ANSI) Standard Z136.1, for ''Safe Use of Lasers'' and the 2000 version of the ANSI Standard Z136.6, for ''Safe Use of Lasers Outdoors''. The trailer based AURA laser system is a mobile platform, which is used to perform laser interaction experiments and tests at various national test sites. The trailer (B70) based AURA laser system is generally operated on the United State Air Force Starfire Optical Range (SOR) at Kirtland Air Force Base (KAFB), New Mexico. The laser is used to perform laser interaction testing inside the laser trailer as well as outside the trailer at target sites located at various distances from the exit telescope. In order to protect personnel, who work inside the Nominal Hazard Zone (NHZ), from hazardous laser emission exposures it was necessary to determine the Maximum Permissible Exposure (MPE) for each laser wavelength (wavelength bands) and calculate the appropriate minimum Optical Density (OD min ) of the laser safety eyewear used by authorized personnel and the Nominal Ocular Hazard Distance (NOHD) to protect unauthorized personnel who may have violated the boundaries of the control area and enter into the laser's NHZ
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On-Chip Laser-Power Delivery System for Dielectric Laser Accelerators
Hughes, Tyler W.; Tan, Si; Zhao, Zhexin; Sapra, Neil V.; Leedle, Kenneth J.; Deng, Huiyang; Miao, Yu; Black, Dylan S.; Solgaard, Olav; Harris, James S.; Vuckovic, Jelena; Byer, Robert L.; Fan, Shanhui; England, R. Joel; Lee, Yun Jo; Qi, Minghao
2018-05-01
We propose an on-chip optical-power delivery system for dielectric laser accelerators based on a fractal "tree-network" dielectric waveguide geometry. This system replaces experimentally demanding free-space manipulations of the driving laser beam with chip-integrated techniques based on precise nanofabrication, enabling access to orders-of-magnitude increases in the interaction length and total energy gain for these miniature accelerators. Based on computational modeling, in the relativistic regime, our laser delivery system is estimated to provide 21 keV of energy gain over an acceleration length of 192 μ m with a single laser input, corresponding to a 108-MV/m acceleration gradient. The system may achieve 1 MeV of energy gain over a distance of less than 1 cm by sequentially illuminating 49 identical structures. These findings are verified by detailed numerical simulation and modeling of the subcomponents, and we provide a discussion of the main constraints, challenges, and relevant parameters with regard to on-chip laser coupling for dielectric laser accelerators.
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... this page: //medlineplus.gov/ency/patientinstructions/000905.htm Laser therapy for cancer To use the sharing features ... Lasers are also used on the skin. How Laser Therapy is Used Laser therapy can be used ...
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... the advantages of laser therapy? What are the disadvantages of laser therapy? What does the future hold ... therapy is appropriate for them. What are the disadvantages of laser therapy? Laser therapy also has several ...
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A laser is used for many medical purposes. Because the laser beam is so small and precise, it enables ... without injuring surrounding tissue. Some uses of the laser are retinal surgery, excision of lesions, and cauterization ...
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Duarte, FJ
2015-01-01
This Second Edition of a bestselling book describes the optics and optical principles needed to build lasers. It also highlights the optics instrumentation necessary to characterize laser emissions and focuses on laser-based optical instrumentation. The book emphasizes practical and utilitarian aspects of relevant optics including the essential theory. This revised, expanded, and improved edition contains new material on tunable lasers and discusses relevant topics in quantum optics.
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Dougherty, Thomas J
2015-03-03
A workpiece cutting apparatus includes a laser source, a first suction system, and a first finger configured to guide a workpiece as it moves past the laser source. The first finger includes a first end provided adjacent a point where a laser from the laser source cuts the workpiece, and the first end of the first finger includes an aperture in fluid communication with the first suction system.
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Křemíkový laser - poslední chybějící článek pro křemíkovou fotonku
Czech Academy of Sciences Publication Activity Database
Luterová, Kateřina; Pelant, Ivan
2004-01-01
Roč. 54, - (2004), s. 320-330 ISSN 0009-0700 R&D Projects: GA ČR GA202/98/0669; GA ČR GP202/01/D030; GA ČR GA202/03/0789; GA AV ČR IAA1010528; GA AV ČR IAA1010809; GA AV ČR IAA1010316; GA MŠk ME 304; GA MŠk ME 486 Institutional research plan: CEZ:AV0Z1010914 Keywords : silicon laser * optical gain * silicon nanocrystal Subject RIV: BM - Solid Matter Physics ; Magnetism
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PROCESSOS HIDRO-EROSIVOS EM SOLOS DEGRADADOS EM RELEVO DE BAIXA DECLIVIDADE
Directory of Open Access Journals (Sweden)
Leonardo dos Santos Pereira
2016-06-01
Full Text Available Muitas pesquisas conferem maior peso na alta declividade do terreno como fator decisivo no processo hidro-erosivo. Porém, foi avaliado que baixas declividades (~4º já são suficientes para se iniciar o escoamento superficial. A pesquisa teve como objetivo fazer uma caracterização físico-química de solo degradado, monitorar o seu potencial matricial e o processo de formação de escoamento em uma sub-bacia do rio Maranduba - Ubatuba/SP, em encosta com baixa declividade. O trabalho se baseou na instalação de parcelas de erosão em solo sem cobertura vegetal para analisar as perdas de solo e água, bem como as propriedades físicas e químicas do solo (Porosidade, textura, densidade, pH e matéria orgânica. As parcelas se localizam na parte intermediária de um morrote com encosta retilínea, esse sofreu alteração em sua morfologia original por meio de um corte de encosta (UTM: 0474211/7395934. O solo do local é um Latossolo que apresenta o horizonte B exposto. Cerca de 6,9 t/ha de solo foram perdidos durante o monitoramento (01 agosto 2013-20 dezembro 2014 e mais de 5.354,7 m3 de água foram escoados superficialmente. Salienta-se a fragilidade dos ambientes degradados de baixa declividade frente às altas taxas de perdas de solo e água, que, no período de 17 meses de monitoramento e com chuvas dentro da normalidade para o município, totalizaram 63 dias com ocorrências de escoamento, em solos que tendem à saturação por períodos prolongados. Portanto, o transporte das partículas de solo superficialmente está atrelado à baixa drenagem do terreno e à perda da resistência do solo, corroborando em períodos longos de umidade antecedente, sendo este um dos fatores decisivos para se iniciar o escoamento superficial.
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Petrushkin, S V
2009-01-01
Laser cooling is an important emerging technology in such areas as the cooling of semiconductors. The book examines and suggests solutions for a range of problems in the development of miniature solid-state laser refrigerators, self-cooling solid-state lasers and optical echo-processors. It begins by looking at the basic theory of laser cooling before considering such topics as self-cooling of active elements of solid-state lasers, laser cooling of solid-state information media of optical echo-processors, and problems of cooling solid-state quantum processors. Laser Cooling of Solids is an important contribution to the development of compact laser-powered cryogenic refrigerators, both for the academic community and those in the microelectronics and other industries. Provides a timely review of this promising field of research and discusses the fundamentals and theory of laser cooling Particular attention is given to the physics of cooling processes and the mathematical description of these processes Reviews p...
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A Intervenção em Psicologia em uma Universidade na Amazônia Sul Ocidental
Directory of Open Access Journals (Sweden)
Madge Porto
Full Text Available Resumo: O objetivo desse relato é descrever uma experiência profissional em Psicologia vivenciada em uma universidade pública, destacando questões como o alcance e a qualidade da intervenção em Psicologia nas políticas públicas de educação superior. Diante da demanda de realizar o trabalho em Psicologia com atendimentos individuais de tratamento, a estratégia foi apresentar um projeto de trabalho no qual a ação principal seria a promoção à saúde, ao mesmo tempo que os relatórios das atividades desenvolvidas eram entregues sistematicamente, demonstrando, a partir de resultados como: níveis baixos de procura e níveis altos de evasão e de custo, que a proposta da gestão não seria a melhor estratégia. As atividades de promoção e prevenção em saúde, com trabalhos em grupo substancialmente, precisariam ser objetivo principal da intervenção em Psicologia em uma universidade. Uma política pública que quer intervir apenas nos sintomas e não nas causas destes, apresenta-se como apoio ao desmonte das universidades públicas. As ações propostas para cuidar da saúde dos servidores e servidoras e estudantes se tornam uma intervenção sem impacto significativo na instituição e que não contribui para a afirmação da universidade gratuita, de qualidade, laica e socialmente referenciada, estando, assim, corroborando para o seu desmonte e, em curto prazo, possibilitar a privatização no lugar de efetivamente contribuir para a construção de uma educação de qualidade.
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Energy Technology Data Exchange (ETDEWEB)
Bachmann, Luciano
2000-07-01
The beam delivery systems, whether using fibers or articulated arms, are very important for the expansion of laser applications into life sciences. This work aims to couple an optical fiber to a home-made Er:Tm:Ho:LiYF{sub 4} laser. For this purpose the beam profile was studied using the beam quality factor M{sup 2} to achieve an homogeneous beam. To determine the M{sup 2} factor, the knife-edge technique was used, relating the laser energy eclipsed by the knife with its transversal position. The resonant cavity was made suitable in order to obtain a stable and homogeneous transversal beam profile, for the optical fiber coupling. It was used a 365 {mu}m diameter core low OH{sup -} content fused silica optical fiber, with a proximal SMA-905 connection and a flat distal end. M{sup 2} factors for the Ho:YLF were between 3 and 8, with a non astigmatic beam, although it was observed a divergence asymmetry in the transversal sections. The coupling efficiency was 96%, and in a repeated operation without any adjustment, the new coupling were 82% and 81%. Lasers have being recently used as an adjunct to conventional endodontic preparation to reduce intracanal microbial, preventing reinfection. The knowledge of thermal profile in endodontic procedures is important to determine laser irradiation conditions avoiding periodontal damages. In this sense, the second scope of this work was to use the Ho:YLF system to register the thermal profile in vitro and to compare the results with those obtained with Nd:YAG and Er:YAG commercial lasers. The temperature was recorded in real time through a thermocouple probe at the root apex , resulting in maximum increase of 7 deg C. (author)
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Directory of Open Access Journals (Sweden)
Clélia Maria Erwenne
2003-12-01
Full Text Available OBJETIVO: Relatar os índices de conservação do globo ocular após tratamento com carboplatina e laser associados ou não a outras formas de tratamento local e radioterapia quando necessário. MÉTODO: Os olhos, virgens de qualquer tratamento, foram inicialmente estadiados, por oftalmoscopia indireta sob narcose ambulatorial, segundo Reese & Ellsworth e os pacientes submetidos à avaliação clínica por pediatra oncologista. Iniciou-se a administração do primeiro ciclo de quimioterapia com carboplatina 200 mg/m², vincristina 1,5 mg/m² e etoposida 150 mg/m² por via endovenosa em 3 dias. Seguiram-se outros ciclos sendo o intervalo entre eles de 21 a 28 dias. De 7 a 15 dias do término do ciclo de quimioterapia, nova oftalmoscopia indireta sob narcose ambulatorial era realizada com descrição dos achados e aplicação de hipertermia por laser Diodo 810 nm, pulso contínuo, e "large spot". O procedimento (quimioterapia e laser foi repetido até completa cicatrização total das lesões ou até que se observasse necessidade de outra modalidade terapêutica como a radioterapia ou a enucleação. Controles periódicos bimensais no primeiro ano e trimestrais nos seguintes foram realizados para reavaliação e tratamento de novas lesões ou recidivas. Acompanhamento clínico por oncologista pediatra foi realizado durante todo o tratamento e seguimento. RESULTADOS: Foram tratados 62 pacientes portadores de RB (32M/30F, 15 unilaterais e 47 bilaterais (total de 107 olhos. A média de idade foi 16,9 meses (2,6 a 71,4. Em 5 pacientes administrou-se 4 ciclos de quimioterapia, nos demais foram necessários mais que 4 e até 8 ciclos. Em 34 olhos não se pode evitar o uso de radioterapia. O tempo médio de seguimento foi de 26,8 meses (5 a 60. Entre os bilaterais os índices de conservação, segundo os estádios de Reese & Ellsworth foram: I 10/11 (90,9%; II 8/9 (88,8%; III 10/10 (100,0%; IV 3/8 (37,5%; V 14/54 (25,9%. Considerando-se o total de
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AVALIAÇÃO DO INCREMENTO EM DIÂMETRO DO MOGNO (Swietenia macrophylla EM UM SAF - RURÓPOLIS-PARÁ
Directory of Open Access Journals (Sweden)
Itabira Jaguaraçú Ricardo Sanches
2016-11-01
Full Text Available Esse trabalho tem como objetivo avaliar o incremento em diâmetro da espécie Swietenia machophylla em um sistema Agroflorestal. Em uma área de 1 ha foram alocadas 5 parcelas de 12 x 24 m. As medições foram realizadas em três ocasiões, sendo: Janeiro de 2014, Janeiro de 2015 e Julho de 2015. Para construção dos histogramas de frequência foram testados os métodos de Sturges e “empírico”. Em um segundo plano histogramas de crescimento foram elaborados tendo em vista a visualização dos diâmetros de cada indivíduo para análise do incremento em diâmetro. O melhor resultado para construção dos histogramas foi o método “empírico”, pois apresentou menor erro. O incremento no DAP médio foi de 0,58 cm entre as três medições, no primeiro período o incremento em diâmetro foi de 11,32, no segundo 11,76 cm e no último 11,90 cm.
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A próclise em sentenças infinitivas preposicionadas em PB
Directory of Open Access Journals (Sweden)
Marco Antonio Martins
2016-12-01
Full Text Available http://dx.doi.org/10.5007/1984-8420.2016v17n1p43 Apresentamos, neste artigo, uma análise formal para a colocação de clíticos em sentenças infinitivas preposicionadas no português brasileiro (PB. A análise se baseia no trabalho desenvolvido por Sena Pereira (2015 que aborda a colocação de clíticos nesse contexto na escrita brasileira dos séculos XIX e XX. Nossa proposta é que preposições que ocupam o núcleo de CP motivam mudanças nos valores atribuídos aos traços-phi e aos traços-V fortes nas categorias funcionais COMP, Tempo e Pessoa no PB. Defendemos que em tal configuração a próclise em PB é derivada do movimento do verbo para a categoria funcional Tempo em que há a associação de traços [+V] e traços [+AGR].
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Laser physics and a review of laser applications in dentistry for children.
Martens, L C
2011-04-01
The aim of this introduction to this special laser issue is to describe some basic laser physics and to delineate the potential of laser-assisted dentistry in children. A brief review of the available laser literature was performed within the scope of paediatric dentistry. Attention was paid to soft tissue surgery, caries prevention and diagnosis, cavity preparation, comfort of the patient, effect on bacteria, long term pulpal vitality, endodontics in primary teeth, dental traumatology and low level laser therapy. Although there is a lack of sufficient evidence taking into account the highest standards for evidence-based dentistry, it is clear that laser application in a number of different aetiologies for soft tissue surgery in children has proven to be successful. Lasers provide a refined diagnosis of caries combined with the appropriate preventive adhesive dentistry after cavity preparation. This will further lead to a new wave of micro-dentistry based on 'filling without drilling'. It has become clear from a review of the literature that specific laser applications in paediatric dentistry have gained increasing importance. It can be concluded that children should be considered as amongst the first patients for receiving laser-assisted dentistry.
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Prevalência de transtornos mentais comuns em trabalhadores de enfermagem em um hospital da Bahia
Directory of Open Access Journals (Sweden)
Eder Pereira Rodrigues
2014-04-01
Full Text Available Neste estudo, objetivou-se descrever a prevalência de "suspeitos" de transtornos mentais comuns (TMC em trabalhadores de enfermagem em um hospital geral, no estado da Bahia. Realizou-se um estudo epidemiológico, de corte transversal, com 309 profissionais de enfermagem, que trabalhavam em atividades assistenciais em um hospital de grande porte. Os profissionais de enfermagem referiram sobrecarga de trabalho e baixa remuneração. As queixas de saúde mais frequentes estavam relacionadas à postura corporal e a saúde mental. A prevalência geral de "suspeitos" de TMC foi de 35,0%. Em relação aos aspectos psicossociais do trabalho, relataram uma alta demanda psicológica e baixo controle sobre as atividades laborais. Os resultados obtidos apontam que as condições de trabalho e saúde observadas, não são adequadas para a efetiva realização do trabalho de enfermagem no hospital estudado.
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Directory of Open Access Journals (Sweden)
Patricia Chaves de Oliveira
2010-06-01
Full Text Available A conservação de espécies prestadoras de serviços ecológicos em paisagens amazônicas como os agros-ecossistemas locais do Baixo Amazonas é de extrema importância no input de minerais através da serrapilheira produzida por estas espécies. Os cecropiais nativos, formados pela espécie Cecropia palmata, dentre outras, a qual é acumuladora de fósforo (P em tecidos foliares e cascas podem prestar um serviço ecológico em paisagens amazônicas com deficiência por fósforo. Os objetivos desta pesquisa foram a observação da translocação do fósforo em folhas ontogeneticamentes diferentes de Cecropia palmata; bem como, a análise da dinâmica do fósforo em solos sob conglomerados de Cecropia palmata. Os teores de fósforo (P em tecidos foliares de Cecropia palmata demonstraram valores elevados, em torno de 8.4 mg/kg em folhas novas e 5,6mg/kg em folhas com maturação fisiológica, sugerindo serrapilheira de alta qualidade para o ambiente. Além disso, os solos sob influência da rizosfera desta espécie apresentaram importantes hot spots de fósforo.
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Femtosecond laser inscribed cladding waveguide lasers in Nd:LiYF4 crystals
Li, Shi-Ling; Huang, Ze-Ping; Ye, Yong-Kai; Wang, Hai-Long
2018-06-01
Depressed circular cladding, buried waveguides were fabricated in Nd:LiYF4 crystals with an ultrafast Yb-doped fiber master-oscillator power amplifier laser. Waveguides were optimized by varying the laser writing conditions, such as pulse energy, focus depth, femtosecond laser polarization and scanning velocity. Under optical pump at 799 nm, cladding waveguides showed continuous-wave laser oscillation at 1047 nm. Single- and multi-transverse modes waveguide laser were realized by varying the waveguide diameter. The maximum output power in the 40 μm waveguide is ∼195 mW with a slope efficiency of 34.3%. The waveguide lasers with hexagonal and cubic cladding geometry were also realized.