823 resultados para Pure Magnesium
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Objectives: The purpose of this study was to evaluate the surfaces of commercially pure titanium (cp Ti) implants modified by laser beam (LS), without and with hydroxyapatite deposition by the biomimetic method (HAB), without (HAB) and with thermal treatment (HABT), and compare them with implants with surfaces modified by acid treatment (AS) and with machined surfaces (MS), employing topographical and biomechanics analysis. Methods: Forty-five rabbits received 75 implants. After 30, 60, and 90 days, the implants were removed by reverse torque and the surfaces were topographically analyzed. Results: At 30 days, statistically significant difference (P < 0.05) was observed among all the surfaces and the MS, between HAB/HABT and AS and between HAB and LS. At 60 days, the reverse torque of LS, HAB, HABT, and AS differed significantly from MS. At 90 days, difference was observed between HAB and MS. The microtopographic analysis revealed statistical difference between the roughness of LS, HAB, and HABT when compared with AS and MS. Conclusions: It was concluded that the implants LS, HAB, and HABT presented physicochemical and topographical properties superior to those of AS and MS and favored the osseointegration process in the shorter periods. In addition, HAB showed the best results when compared with other surfaces. © 2012 John Wiley & Sons A/S.
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The semiotics of C S. Peirce presents fundamental concepts to discover aspects of the indexing process, including representation and classes of signs. However, we still know little of its theoretical potential for subject indexing. We believe that the main difficulty in the proposals to understand the process of subject indexing based on Peircean semiotics stems from an incomplete interpretation of his semiotic system. This paper attempts to describe the contributions of Peircean semiotics to subject indexing. First, we analyze some of the concepts of the branches of semiotics, after which, we discuss strategies for conceptual approximation. Secondly, and aiming to raise the level of interlocution between the areas, we intend to argue that subject indexing is an inferential process, as explained by the second branch of semiotics. Thus, we seek to go beyond the level of speculative grammar, the first branch of semiotics, to forge a closer link with pure or critical logic, the second branch. We conclude that the indexer's work does not produce a mere reflection of what already exists in documents, but involves an instigating action to discover, through the inferential matrix, the meaning of a text in order to find the subject and the most appropriate subject added entry to the information system.
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In this work, a particular BRST-exact class of deformations of the b ghost in the non-minimal pure spinor formalism is investigated and the impact of this construction in the N= 2 ĉ = 3 topological string algebra is analysed. As an example, a subclass of deformations is explicitly shown, where the U (1) current appears in a conventional form, involving only the ghost number currents. Furthermore, a c ghost like composite field is introduced, but with an unusual construction. © 2013 SISSA, Trieste, Italy.
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Biodiesel fuel is gradually replacing petroleum-based diesel oil use. Despite the biodiesel being considered friendlier to the environment, little is known about its effects in aquatic organisms. In this work we evaluated whether biodiesel exposure can affect oxidative stress parameters and biotransformation enzymes in armored catfish (Pterygoplichthys anisitsi, Loricariidae), a South American endemic species. Thus, fish were exposed for 2 and 7d to 0.01mLL-1 and 0.1mLL-1 of pure diesel, pure biodiesel (B100) and blends of diesel with 5% (B5) and 20% (B20) biodiesel. Lipid peroxidation (malondialdehyde) levels and the activities of the enzymes glutathione S-transferase, superoxide dismutase, catalase and glutathione peroxidase were measured in liver and gills. Also, DNA damage (8-oxo-7, 8-dihydro-2'-deoxyguanosine) levels in gills and 7-ethoxyresorufin-O-deethylase activity in liver were assessed. Pure diesel, B5 and B20 blends changed most of the enzymes tested and in some cases, B5 and B20 induced a higher enzyme activity than pure diesel. Antioxidant system activation in P. anisitsi was effective to counteract reactive oxygen species effects, since DNA damage and lipid peroxidation levels were maintained at basal levels after all treatments. However, fish gills exposed to B20 and B100 presented increased lipid peroxidation. Despite biodiesel being more biodegradable fuel that emits less greenhouse gases, the increased lipid peroxidation showed that biofuel and its blends also represent hazards to aquatic biota. © 2013 Elsevier Ltd.
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The orbit is an irregular conical cavity formed from 7 bones including the frontal, sphenoid, zygomatic, maxillary, ethmoid, lacrimal, and palatine bones. Fractures of the internal orbit can cause a number of problems, including diplopia, ocular muscle entrapment, and enophthalmos. Although muscle entrapment is relatively rare, diplopia and enophthalmos are relatively common sequelae of internal orbital fractures. Medial orbital wall fracture is relatively uncommon and represents a challenge for its anatomical reconstruction. In this context, autogenous bone graft has been the criterion standard to provide framework for facial skeleton and orbital walls. Therefore, it is possible to harvest grafts of varying size and contour, and the operation is performed through the bicoronal incision, which is the usual approach to major orbital reconstruction. Thus, this article aimed to describe a patient with a pure medial orbital wall fracture, and it was causing diplopia and enophthalmos. The orbital fracture was treated using autogenous bone graft from calvarial bone. The authors show a follow-up of 12 months, with facial symmetry and without diplopia and enophthalmos. In addition, a computed tomography scan shows excellent bone healing at the anterior and posterior parts of the medial orbital wall reconstruction. Copyright © 2013 by Mutaz B. Habal, MD.
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Objective Psychiatric comorbidity is the rule in obsessive-compulsive disorder (OCD); however, very few studies have evaluated the clinical characteristics of patients with no co-occurring disorders (non-comorbid or pure OCD). The aim of this study was to estimate the prevalence of pure cases in a large multicenter sample of OCD patients and compare the sociodemographic and clinical characteristics of individuals with and without any lifetime axis I comorbidity. Method A cross-sectional study with 955 adult patients of the Brazilian Research Consortium on Obsessive-Compulsive Spectrum Disorders (C-TOC). Assessment instruments included the Yale-Brown Obsessive-Compulsive Scale, the Dimensional Yale-Brown Obsessive-Compulsive Scale, The USP-Sensory Phenomena Scale and the Brown Assessment of Beliefs Scale. Comorbidities were evaluated using the Structured Clinical Interview for DSM-IV Axis I Disorders. Bivariate analyses were followed by logistic regression. Results Only 74 patients (7.7%) presented pure OCD. Compared with those presenting at least one lifetime comorbidity (881, 92.3%), non-comorbid patients were more likely to be female and to be working, reported less traumatic experiences and presented lower scores in the Y-BOCS obsession subscale and in total DY-BOCS scores. All symptom dimensions except contamination-cleaning and hoarding were less severe in non-comorbid patients. They also presented less severe depression and anxiety, lower suicidality and less previous treatments. In the logistic regression, the following variables predicted pure OCD: sex, severity of depressive and anxious symptoms, previous suicidal thoughts and psychotherapy. Conclusions Pure OCD patients were the minority in this large sample and were characterized by female sex, less severe depressive and anxious symptoms, less suicidal thoughts and less use of psychotherapy as a treatment modality. The implications of these findings for clinical practice are discussed. © 2013 Elsevier Inc. All rights reserved.
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BACKGROUND There is little information on the interaction between magnesium sulphate (MgSO4) and rocuronium in elderly patients. With a growing number of older patients who need surgical procedures, it is increasingly important to study this age group. OBJECTIVE To evaluate the effects of MgSO4 administration on the pharmacodynamics of rocuronium in patients aged 60 years or older. DESIGN A randomised controlled trial. SETTING A tertiary care hospital. PATIENTS Sixty-four patients, aged 60 years or older, American Society of Anesthesiologists (ASA) physical status classes I to III, scheduled for elective oncological head and neck surgery. Exclusion criteria were severe renal insufficiency (calculated creatinine clearance <30 ml min-1), preoperatorive serum magnesium concentration of more than 1.25 mmol l1 and patients receiving drugs known to affect neuromuscular function. INTERVENTIONS Patients were randomly allocated to one of two groups: in the magnesium group, patients received MgSO4 30mgkg1 intravenously, for 10 min, and then a continuous intravenous infusion at a rate of 1 g h-1. The control group received the same volume of physiological saline. Neuromuscular function was evaluated continuously in both groups. MAIN OUTCOME MEASURES Total recovery time was the primary outcome. Onset time, clinical duration, recovery index and recovery time were considered as secondary endpoints. Values are given as mean [SD]. RESULTS Total recovery time from neuromuscular block (NMB) was 113 [36] min in the magnesium group and 101 [39] min in the control group. Clinical duration was 69 [23] min in the magnesium group and 59 [28] min in the control group. Recovery index was 19 [36] min in the magnesium group and 17 [6] min in the control group. Recovery timewas 44 [22] min in the magnesium group and 42 [18] min in the control group. There were no statistically significant differences between the groups in any of the recovery indices. In the magnesium group, the mean onset time was 144 [58] s, significantly shorter than the onset time in the group that received physiological saline, which was 187 [90] s (P-0.03). Group variances were compared using an F test: onset time varied significantly less in the magnesium group (P-0.02). CONCLUSION In oncology patients of 60 or more years of age, preadministration of MgSO4, with the doses used in this study, significantly reduced the onset time of NMB induced by rocuronium. © 2013 European Society of Anaesthesiology.
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Pós-graduação em Medicina Veterinária - FMVZ
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Agronomia (Energia na Agricultura) - FCA
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Neste trabalho, cristais de sulfato níquel dopados com íons de manganês (NSH: Mn) e cristais de sulfato níquel dopados com de íon de magnésio (NMgSH) foram crescidos e posteriormente caracterizados pelas técnicas de difração de raios X e de espectroscopia Raman. Os resultados obtidos mostraram que os cristais dopados possuem estrutura muito semelhante a do cristal de sulfato de níquel puro (NSH), com uma deformação anisotrópica nas dimensões da célula unitária em relação ao cristal puro. O objetivo do presente estudo foi crescer dois novos monocristais de boa qualidade óptica para serem usados como filtros ópticos de banda passante. Os cristais de sulfato de níquel hexa-hidratado (NHS) são conhecidos por possuírem espectros de transmissão óptica, que tem atraído muita atenção, pois apresentam duas regiões com alta eficiência de transmissão, aproximadamente 80%, sendo a primeira região entre 200 e 350 nm e a segunda entre 400 e 600 nm, e uma alta eficiência de absorção em outras regiões do espectro UV-VIS. Um espectro de transmissão de luz com estas características é semelhante a um filtro óptico. Analises Termogravimetric (TGA) foram realizadas para cristais puros e dopados. A temperatura de decomposição obtida para o NSH foi de 73 ° C, enquanto que os cristais de NSH:Mn e NMgSH apresentam valores de 82 ° C e 86 º C, respectivamente. Como pode ser facilmente percebido, a estabilidade térmica de cristais com o íons de Mn ou Mg em suas estruturas é significativamente maior. A banda de transmissão entre 200 e 350 nm no espectro óptico de NSH foi observada com redução significativa em sua largura nos espectros de transmissão dos cristais dopados restringindo assim a região do espectro conhecida como UVA.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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O mapeamento geológico realizado na área de Nova Canadá, porção sul do Domínio Carajás, Província Carajás, possibilitou a individualização de duas unidades de caráter máfico e intrusivas nos granitoides do Complexo Xingu e, mais restritamente, na sequência greenstone belt do Grupo Sapucaia. São representadas por diques de diabásio isotrópicos e por extensos corpos de anfibolito, com os últimos descrevendo texturas nematoblástica e granoblástica, de ocorrência restrita à porção SW da área. Ambos apresentam assinatura de basaltos subalcalinos de afinidade toleítica, sendo que os diques de diabásio são constituídos por três variedades petrográficas: hornblenda gabronorito, gabronorito e norito, sendo essas diferenças restritas apenas quanto à proporção modal de anfibólio, orto- e clinopiroxênio, já que texturalmente, as mesmas não apresentam diferenças significativas. São formados por plagioclásio, piroxênio (orto- e clinopiroxênio), anfibólio, minerais óxidos de Fe-Ti e olivina, apresentam um padrão ETR moderadamente fracionado, discreta anomalia negativa de Eu, ambiente geotectônico correspondente a intraplaca continental, e assinaturas dos tipos OIB e E-MORB. Já os anfibolitos são constituídos por plagioclásio, anfibólio, minerais opacos, titanita e biotita, mostram um padrão ETR horizontalizado, com anomalia de Eu ausente, sendo classificados como toleítos de arco de ilha e com assinatura semelhante aos N-MORB. Os dados de química mineral obtidos nessas unidades mostram que, nos diques de diabásio, o plagioclásio não apresenta variações composicionais significativas entre núcleo e borda, sendo classificados como labradorita, com raras andesina e bytownita; o anfibólio mostra uma gradação composicional de Fe-hornblenda para actinolita, com o aumento de sílica. Nos anfibolitos, o plagioclásio mostra uma grande variação composicional, de oligoclásio à bytownita nas rochas foliadas, sendo que nas menos deformadas, sua classificação é restrita à andesina sódica. O piroxênio, presente apenas nos diabásios, exibe considerável variação em sua composição, revelando um aumento no teor de magnésio nos núcleos, e de ferro e cálcio, nas bordas, permitindo classificá-los em augita, pigeonita (clinopiroxênio) e enstatita (ortopiroxênio). Os diabásios apresentam titanomagnetita, magnetita e ilmenita como os principais óxidos de Fe-Ti, permitindo reconhecer cinco formas distintas de ilmenita nessas rochas: ilmenita treliça, ilmenita sanduíche, ilmenita composta interna/externa, ilmenita em manchas e ilmenita individual. Feições texturais e composicionais sugerem que a titanomagnetita e os cristais de ilmenita composta externa e individual foram originados durante o estágio precoce de cristalização. Durante o estágio subsolidus, a titanomagnetita foi afetada pelo processo de oxi-exsolução, dando origem a intercrescimentos de magnetita pobre em titânio com ilmenita (ilmenitas treliça, em mancha, sanduíche e composta interna). Os anfibolitos possuem a ilmenita como único mineral óxido de Fe e Ti ocorrendo, portanto, sob a forma de ilmenita individual, onde encontra-se sempre associada ao anfibólio e à titanita. Os valores mais elevados de suscetibilidade magnética (SM) estão relacionados aos gabronoritos e noritos, os quais exibem maiores conteúdos modais de minerais opacos e apresentam titanomagnetita magmática em sua paragênese. A variedade hornblenda gabronorito define as amostras com valores intermediários de SM. Os menores valores de SM são atribuídos aos anfibolitos, que são desprovidos de magnetita. A correlação negativa entre valores de SM com os conteúdos modais de minerais ferromagnesianos indica que os minerais paramagnéticos (anfibólio e piroxênio) não possuem influência significativa no comportamento magnético dos diabásios, enquanto nos anfibolitos a tendência de correlação positiva entre estas variáveis pode sugerir que estas fases são as principais responsáveis pelos seus valores de SM. Dados geotermobarométricos obtidos a partir do par titanomagnetita-ilmenita nos diabásios indicam que estes se formaram em condições de temperatura (1112°C) e Fo2 (-8,85) próximas daquelas do tampão NNO.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)