43 resultados para OPEN-ANGLE GLAUCOMA


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What is the importance of open habitat in a predominantly closed forest to the dung beetle assemblage? The Atlantic Forest in Brazil is one of the most highly disturbed ecosystems and is mainly represented by fragmented areas. However, in places where human disturbances have ceased, certain areas are showing a natural regeneration pattern. The aim of the present study was to determine how the dung beetle assemblage responds to distinct habitat structures in a fragment of Atlantic Forest. For such, open and closed forest areas were sampled in a fragment of the Atlantic Forest in the northeastern region of Brazil. Pitfall traps baited with excrement and carrion were used to collect the beetles. A total of 7,267 individuals belonging to 35 species were captured. Canthon chalybaeus and C. mutabilis were restricted to open areas. Nearly 90% of the individuals of C. aff. simulans and Deltochilum aff. irroratum were identified in these areas. A higher percentage (> 50%) of Canthon staigi, Dichotomius aff. depressicolis and D. aff. sericeus occurred in closed areas. Abundance differed between areas, with higher values in closed areas. Richness was not influenced by the habitat structure. NMDS ordination exhibited the segregation of areas and ANOSIM confirmed that this variable explained the assemblage of dung beetle species. The findings of the present study validate that open areas are associated to more restrictive conditions, limiting a higher abundance of dung beetle. Although situated near preserved fragments, the studied open areas increase the heterogeneity of the general landscape.

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The quantification of ammonia (NH3) losses from sugarcane straw fertilized with urea can be performed with collectors that recover the NH3 in acid-treated absorbers. Thus, the use of an open NH3 collector with a polytetrafluoroethylene (PTFE)-wrapped absorber is an interesting option since its cost is low, handling easy and microclimatic conditions irrelevant. The aim of this study was to evaluate the efficiency of an open collector for quantifying NH3-N volatilized from urea applied over the sugarcane straw. The experiment was carried out in a sugarcane field located near Piracicaba, São Paulo, Brazil. The NH3-N losses were estimated using a semi-open static collector calibrated with 15N (reference method) and an open collector with an absorber wrapped in PTFE film. Urea was applied to the soil surface in treatments corresponding to rates of 50, 100, 150 and 200 kg ha-1 N. Applying urea-N fertilizer on sugarcane straw resulted in losses NH3-N up to 24 % of the applied rate. The amount of volatile NH3-N measured in the open and the semi-open static collector did not differ. The effectiveness of the collection system varied non-linearly, with an average value of 58.4 % for the range of 100 to 200 kg ha-1 of urea-N. The open collector showed significant potential for use; however, further research is needed to verify the suitability of the proposed method.

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A comunicação científica ampliou seus horizontes de troca de dados, informações e conhecimentos com o aparecimento dos open archives, arquivos que congregam e-prints das diversas áreas do saber e que são abertos à consulta pública, bem como à publicação automatizada dos trabalhos por parte dos pesquisadores. A experiência americana em áreas da física, matemática e ciência da computação, entre outras, demonstra a viabilidade e utilidade dos arquivos abertos como ponto de convergência para comunidades de pesquisadores que se vêem sem fronteiras geográficas ou institucionais para o intercâmbio de seus resultados de pesquisas.

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The author reviews past work with Ibict and the global progress made by the Open Access Movement. He postulates a theory of open access being an example of a complex adaptive system created by Internet-based scholarly publishing. Open access could be the cause of a cascade of increasing complexity and opportunities that will reshape this system. He has chosen the pervasive and global "Connectedness" created by the internet and the content spaces it provides for open access collections as a "simple disruptive agent". He discusses how connectedness influences infinite variety, creativity, work, change, knowledge, and the information economy. Case studies from the University of New Mexico Libraries are used where appropriate.

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Worldwide initiatives toward digital library (DL) support for electronic theses and dissertations (ETDs), facilitated by the work of the Networked Digital Library of Theses and Dissertations (NDLTD), are a key part of the move toward open access. When all graduate students learn to use openly available ETDs, and have experience with authoring and submission in connection with their own research results, it will be easy for them to continue these efforts through other contributions to open access. When all universities support ETD activities, they will be key participants in institutional repositories and open access, and will have engaged in discussion and infrastructure development supportive of further open access activities. Understanding of open access also can be facilitated through modeling of all of these efforts using the 5S framework, considering the key aspects of DL development: Societies, Scenarios, Spaces, Structures, and Streams.

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This paper describes a project led by the Instituto Brasileiro de Informações em Ciência e Tecnologia (Ibict), a government institution, to build a national digital library for electronic theses and dissertations - Bibliteca Digital de Teses e Dissertações (BDTD). The project has been a collaborative effort among Ibict, universities and other research centers in Brazil. The developers adopted a system architecture based on the Open Archives Initiative (OAI) in which universities and research centers act as data providers and Ibict as a service provider. A Brazilian metadata standard for electronic theses and dissertations was developed for the digital library. A toolkit including open source package was also developed by Ibict to be distributed to potential data providers. BDTD has been integrated with the international initiative: the Networked Digital Library of Thesis and Dissertation (NDLTD). Discussions in the paper address various issues related to project design, development and management as well as the role played by Ibict. Conclusions highlight some important lessons learned to date and challenges for the future in expanding the BDTD project.

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The objetive of this work was to evaluate the influence of intergenotypic competition in open-pollinated families of Eucalyptus and its effects on early selection efficiency. Two experiments were carried out, in which the timber volume was evaluated at three ages, in a randomized complete block design. Data from the three years of evaluation (experiment 1, at 2, 4, and 7 years; and experiment 2, at 2, 5, and 7 years) were analyzed using mixed models. The following were estimated: variance components, genetic parameters, selection gains, effective number, early selection efficiency, selection gain per unit time, and coincidence of selection with and without the use of competition covariates. Competition effect was nonsignificant for ages under three years, and adjustment using competition covariates was unnecessary. Early selection for families is effective; families that have a late growth spurt are more vulnerable to competition, which markedly impairs ranking at the end of the cycle. Early selection is efficient according to all adopted criteria, and the age of around three years is the most recommended, given the high efficiency and accuracy rate in the indication of trees and families. The addition of competition covariates at the end of the cycle improves early selection efficiency for almost all studied criteria.

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The application of one-dimensional proton high-resolution magic angle spinning (¹H HR-MAS) NMR combined with a typical advantages of solid and liquid-state NMR techniques was used as input variables for the multivariate statistical analysis. In this paper, different cultivars of beans (Phaseolus vulgaris) developed and in development by Embrapa - Arroz e Feijão were analyzed by ¹H HR-MAS, which have been demonstrated to be a valuable tool in its differentiation according chemical composition and avoid the manipulation of the samples as used in other techniques.

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QSAR modeling is a novel computer program developed to generate and validate QSAR or QSPR (quantitative structure- activity or property relationships) models. With QSAR modeling, users can build partial least squares (PLS) regression models, perform variable selection with the ordered predictors selection (OPS) algorithm, and validate models by using y-randomization and leave-N-out cross validation. An additional new feature is outlier detection carried out by simultaneous comparison of sample leverage with the respective Studentized residuals. The program was developed using Java version 6, and runs on any operating system that supports Java Runtime Environment version 6. The use of the program is illustrated. This program is available for download at lqta.iqm.unicamp.br.

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The need for automated analyzers for industrial and environmental samples has triggered the research for new and cost-effective strategies of automation and control of analytical systems. The widespread availability of open-source hardware together with novel analytical methods based on pulsed flows have opened the possibility of implementing standalone automated analytical systems at low cost. Among the areas that can benefit from this approach are the analysis of industrial products and effluents and environmental analysis. In this work, a multi-pumping flow system is proposed for the determination of phosphorus in effluents and polluted water samples. The system employs photometric detection based on the formation of molybdovanadophosphoric acid, and the fluidic circuit is built using three solenoid micropumps. The detection is implemented with a low cost LED-photodiode photometric detection system and the whole system is controlled by an open-source Arduino Uno microcontroller board. The optimization of the timing to ensure the color development and the pumping cycle is discussed for the proposed implementation. Experimental results to evaluate the system behavior are presented verifying a linear relationship between the relative absorbance and the phosphorus concentrations for levels as high as 50 mg L-1.

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Photoacoustic spectroscopy provides information about both amplitude and phase of the response of a system to an optical excitation process. This paper presents the studies of the phase in the electron transfer process between octaethylporphyn (OEP) and quinone molecules dispersed in a polymeric matrix. It was observed a tendency in the phase behavior to small values only in the spectral region near to 620 nm, while for shorter wavelength did not show any tendency. These measurements suggested that the electron transfer to acceptor occurred with the participation of octaethylporphyn singlet excited state.

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ABSTRACTFour stands of 28-year-old radiata pine (Pinus radiata D. Don) grown in the eighth region (Biobio) of Chile were sampled to determine the effect of tree spacing on the microfibril angle. The samples were taken at two different stem levels of the tree, 2.5 m and 7.5 m, with increment strip taken in the Nothern direction. The four experimental stands were characterized by the following spacing 2x2, 2x3, 3x4 and 4x4. The microfibril angle was measured by X-ray diffraction with the SilviScan technology at the FP-Innovation-Paprican Division in Vancouver, Canada. The results showed a significant effect of tree spacing on the microfibril angle in both juvenile wood and mature wood as well as at the two stem levels considered. The minimum (9.42º) was reached in 2x2 stand at 7.5 m in mature wood, while maximum microfibril angle (24.54º) was obtained in 2x3 stand at 2.5 m in juvenile wood. Regarding the effect of tree spacing, 4x4 stand had the lowest microfibril angle,except in mature wood at 7.5 m where 4x4 had the highest microfibril angle (11°) of the four stands.

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ABSTRACTScarlet Morning Glory is considered to be an infesting weed that affects several crops and causes serious damage. The application of chemical herbicides, which is the primary control method, requires a broad knowledge of the various characteristics of the solution and application technology for a more efficient phytosanitary treatment. Therefore this study aimed to characterize the effect of rainfall incidence on the control of Ipomoea hederifolia, considering droplet size, surface tension, contact angle of droplets formed by herbicides liquid on vegetal and artificial surfaces, associated to adjuvants and the volumetric distribution profile of the spray jet. The addition of the adjuvants to the herbicide spraying liquid improved the application quality, as it influenced the angle formed by the spray by broadening the deposition band of the spray nozzle and thus the possible distance between the nozzles on spray boom and due the changes at droplet size, which contribute to a safety application. The rainfall occurrence affected negatively the weed control with the different spraying liquids and also the dry matter weight, suggesting that the phytosanitary product applied was washed off.

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OBJECTIVE: to evaluate the outcome of abdominal wall integrity of both techniques. METHODS: a retrospective study was carried out at the Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, identifying the patients undergoing temporary abdominal closure (TAC) from January 2005 to December 2011. Data were collected through the review of clinical charts. Inclusion criteria were indication of TAC and survival to definitive abdominal closure. In the post-operative period only a group of three surgeons followed all patients and performed the reoperations. RESULTS: Twenty eightpatients were included. The difference in primary closure rates and mean time for fascial closure did not reach statistical significance (p=0.98 and p=0.23, respectively). CONCLUSION: VAC and Bogota Bag do not differ significantly regarding the outcome of abdominal wall integrity, due to the monitoring of a specific team and the adoption of progressive closure

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Objective: to analyze the differences in mortality rates, length of hospital stay, time of surgery and the conversion rate between elective open cholecystectomies (OC) and laparoscopic ones (LC) in elderly patients. Methods : we evaluated medical records of patients 65 years of age or older undergoing open or laparoscopic cholecystectomy at the Hospital Regional de Mato Grosso do Sul between January 2008 and December 2011. We excluded individuals operated in non-elective scenarios or who underwent intraoperative cholangiography. Results : we studied 113 patients, of whom 38.1% were submitted to the OC and 61.9%, to LC. Women accounted for 69% of patients and men, for 31%. The conversion rate was 2.9%. The mean age and duration of the procudure was 70.1 and 84 minutes, respectively, with no significant difference between OC and LC. Patients undergoing LC had shorter hospital stays (2.01 versus 2.95 days, p=0.0001). We identified operative complications in sixpatients (14%) after OC and in nine (12%) after LC, with no statistical difference. Conclusion : there was no difference in morbidity and mortality when comparing OC with LC. The laparoscopic approach led to shorter hospital stay. Operative time did not differ between the two access routes. The conversion rate was similar to other studies.