931 resultados para Non line of sight (NLOS)
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The non-eruption of teeth due to highly keratinized gingival mucosa is a frequent event in the pediatric dentistry, which harms the oral aesthetics and function. A surgical excision of the involved area is indicated, exposing the non-erupted tooth. This procedure involves anesthesia and cutting instruments that may increase the fear and anxiety in young patients. The use of new technologies has avoided these instruments and has promoted more comfort to the patients. This study presents clinical cases in which gingivectomy was performed using the innovative method with an ultrasound-activated CVD tip. It was concluded that this method presented effectiveness, promoted more comfort, and less fear to the patients, making its use a viable alternative to pediatric surgery.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The greatest challenge of undergraduate engineering courses is to encourage creativity, cooperation with other students, teamwork, and motivation in the first years of their courses. While students have little or no contact with advanced disciplines, it is very difficult to attract their interests and encourage them to develop the skills in their undergraduate courses. This work aims to achieve these objectives through a mini-factory project involving the construction of a production line of ceramic tiles on a laboratory scale, from the ceramic processing using raw materials to the shipping of the final product. Having been given an established monthly demand for ceramic tiles, the students determined the construction requirements of the mini-factory, as they have created the layout, including the processing equipment, the dimensioning of equipment, and its operational structure. This article intends to describe the successful creation of the ceramic tile mini-factory, including the objectives, benefits, and inherent difficulties of the process and the receptivity of the exercise by the students involved.
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The goal of this study is to present and test a conceptual framework that describes the technical aspects (TA), human/organizational aspects (HOA) of the adoption of green product development (GPD) practices and the effect of these practices on firms'environmental (EP), operational (OP) and market performance (MP). To this end, after reviewing the literature on these themes, a conceptual framework with 5 hypotheses is proposed. These hypotheses were tested on 62 Brazilian companies through structural equation modeling using SmartPLS 2.0M3. The main results of this study are as follows: (a) in general, the proposed framework obtained adequate goodness of fit statistics (GoF); (b) technological factors are shown to have an influence on the adoption of GPD practices, and those practices are related to company EP, OP and MP, thus confirming 4 hypotheses of the study; and (c) one of the study's hypotheses is not validated, indicating that the relationship of human/organizational aspects to GPD must be further analyzed. This work extends the literature because: (a) the conceptual framework tested in this study establishes several concepts that have been only partially tested in the previous literature; (b) this work presents evidence about Brazil, where the themes addressed herein have not been yet been thoroughly investigated; and (c) the non-validation of the hypothesis regarding the relationship between human/ organizational aspects with respect to the adoption of product-related environmental practices requires attention. (C) 2014 Elsevier Ltd. All rights reserved.
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OBJECTIVE: To assess the presence of microorganism contamination in the preservation solution for transplant organs (kidney/pancreas). Method: Between August 2007 and March 2008, 136 samples of preservation solution were studied prior to graft implantation. Variables related to the donor and to the presence of microorganisms in the preservation solution of organs were evaluated, after which the contamination was evaluated in relation to the recipient culture variable. Univariate and multivariate statistical analyses were performed. RESULTS: The contamination rate of the preservation solution was 27.9%. Coagulase-negative Staphylococcus was the most frequently isolated microorganism. However, highly virulent agents, such as fungi and enterobacteria, were also isolated. In univariate analysis, the variable donor antibiotic use was significantly associated to the contamination of the preservation solution. on the other hand, multivariate analysis found statistical significance in donor antibiotic use and donor's infectious complications variables. CONCLUSIONS: In this study, 27.9% of the preservation solutions of transplant organs were contaminated. Infectious diseases and non-use of antibiotics by the donor were significantly related to the presence of microorganisms in organ preservation solutions. Contamination in organ preservation solutions was not associated with infection in the recipient.
Uncommon crown-root fracture treated with adhesive tooth fragment reattachment: 7 years of follow-up
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Crown-root fractures account for 5% of all fractures in permanent teeth and can involve enamel, dentin, and cementum. Depending on whether there is pulpal involvement, these problems may be classified as complicated (which are more common) or noncomplicated. The treatment depends on the level of the fracture line, root length and/or morphology, and esthetic needs. Several treatment strategies are available for esthetic and functional rehabilitation in crown-root fractures. Adhesive tooth fragment reattachment is the most conservative restorative option when the tooth fragment is available and the biological width has no or minimal violation. This article reports a case of an uncomplicated crown-root fracture in the permanent maxillary right central incisor of a young patient who received treatment with adhesive tooth fragment reattachment, preserving the anatomic characteristics of the fractured tooth after periodontal intervention. The fracture line of the fragment had an unusual shape, starting on the palatal side and extending to the buccal side subgingivally. After 7 years, the attached coronal fragment remained in position with good esthetics, as well as clinical and radiographic signs of pulpal vitality, periodontal health, and root integrity, thus indicating success.
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Results of photoluminescence measurements for natural and synthetic alexandrite (BeAl2O4:Cr3+) are presented, where the samples are excited by the 488 nm line of an Ar+ laser, at different temperatures. The main issue is the analysis of the Cr3+ transition in the chrysoberyl matrix (BeAl2O4), with major technological application as active media for laser action. Results indicate anomalous behavior of Cr3+ transition depending on the measurement temperature. A simple model to explain the phenomena is suggested.
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Natural frequencies were analyzed (axial, torsional and flexural) and frequency response of a vertical rotor with a hard disk at the edge through the classical and complex modal analysis. The mathematical modeling was based on the theory of Euler-Bernoulli beam. The equation that rules the movement was obtained through the Lagrangian formulation. The model considered the effects of bending, torsion and axial deformation of the shaft, besides the gravitational and gyroscopic effects. The finite element method was used to discretize the structure into hollow cylindrical elements with 12 degrees of freedom. Mass, stiffness and gyroscopic matrices were explained consistently. This type of tool, based on the use of complex coordinates to describe the dynamic behavior of rotating shaft, allows the decomposition of the system in two submodes, backward and forward. Thus, it is possible to clearly visualize that the orbit and direction of the precessional motion around the line of the rotating shaft is not deformed. A finite element program was developed using Matlab ®, and numerical simulations were performed to validate this model.
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The objective of this paper is to analyse and to discuss the ethical issues in the field of research known as neuromarketing, a tool used to improve innovation in companies. It uses techniques available to neuroscientists, both newer and more sophisticated ones along with traditional ones, but now for new purposes. From the beginning, this new area has evoked discussions about ethical aspects related to the results presented. Despite the unrestricted controversy surrounding the theme, few studies have discussed ethical issues involved in this line of research in a pragmatic manner. In this sense, this paper seeks to analyse and discuss ethical issues in neuromarketing research through a literature review and the proposal for a framework of ethical mapping. This framework revealed the ethical implications that would be most prominent in certain research situations: the purpose of utilising neuromarketing techniques, organisational type, and industrial sector, among others.
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We reviewed the subspecies listed by Rice (1998) and those described since (a total of 49, in 19 species), assessing them against the criteria recommended by the recent Workshop on Shortcomings of Cetacean Taxonomy in Relation to Needs of Conservation and Management (Reeves et al., 2004). The workshop suggested that the subspecies concept can be construed to cover two types of entities: a) lineages diverging but not quite far along the continuum of divergence (still having significant gene flow with another lineage or lineages) to be judged as species, and b) lineages that may well be species but for which not enough evidence is yet available to justify their designation as such. As a criterion for support of a subspecies, the workshop suggested as a guideline that there be at least one good line of either morphological or appropriate genetic evidence. "Appropriate" was not defined; the recommendation was that that be left up to the taxonomist authors of subspecies and to their professional peers. A further recommendation was that evidence on distribution, behavior and ecology should be considered not as primary but as supporting evidence, as there was not agreement at the workshop that such characters are necessarily stable (in the case of distribution) or inherent (behavior and ecology).
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As with many organisms across the globe, Cicindela nevadica lincolniana is threatened with extinction. Understanding ecological factors that contribute to extinction vulnerability and what methods aid in the recovery of those species is essential in developing successful conservation programs. Here we examine behavioral mechanisms for niche partitioning along with improving techniques for captive rearing protocol and increasing public awareness about the conservation of this local insect. Ovipositional selectivity was examined for Cicindela nevadica lincolniana, Cicindela circumpicta, Cicindela togata, Cicindela punctulata, and Cicindela fulgida. Models reflect that these species of co-occurring tiger beetles select different ranges of salinity in which to oviposit thereby reducing the potential for interspecific competition. In a second study, thermoregulatory niche partitioning was examined for the same complex of tiger beetle species. Time spent in the sun, on different substrates, and engaging in various behaviors associated with thermoregulation were significantly different during different parts of the day and between species. I continued along a previous line of study to develop a viable captive rearing program. So far fourteen adult Cicindela nevadica lincolniana have been successfully reared in captivity. Overwintering mortality has been determined as a key factor in the mortality of this species in captivity. Finally, I examined the potential for using the visual arts to promote the conservation of Cicindela nevadica lincolniana and associated saline wetlands. The results from surveys conducted at the exhibit suggest that art exhibits can have a strong positive impact on members of the community.
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We address the investigation of the solvation properties of the minimal orientational model for water originally proposed by [Bell and Lavis, J. Phys. A 3, 568 (1970)]. The model presents two liquid phases separated by a critical line. The difference between the two phases is the presence of structure in the liquid of lower density, described through the orientational order of particles. We have considered the effect of a small concentration of inert solute on the solvent thermodynamic phases. Solute stabilizes the structure of solvent by the organization of solvent particles around solute particles at low temperatures. Thus, even at very high densities, the solution presents clusters of structured water particles surrounding solute inert particles, in a region in which pure solvent would be free of structure. Solute intercalates with solvent, a feature which has been suggested by experimental and atomistic simulation data. Examination of solute solubility has yielded a minimum in that property, which may be associated with the minimum found for noble gases. We have obtained a line of minimum solubility (TmS) across the phase diagram, accompanying the line of maximum density. This coincidence is easily explained for noninteracting solute and it is in agreement with earlier results in the literature. We give a simple argument which suggests that interacting solute would dislocate TmS to higher temperatures.
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In this study we address the problem of the response of a (electro)chemical oscillator towards chemical perturbations of different magnitudes. The chemical perturbation was achieved by addition of distinct amounts of trifluoromethanesulfonate (TFMSA), a rather stable and non-specifically adsorbing anion, and the system under investigation was the methanol electro-oxidation reaction under both stationary and oscillatory regimes. Increasing the anion concentration resulted in a decrease in the reaction rates of methanol oxidation and a general decrease in the parameter window where oscillations occurred. Furthermore, the addition of TFMSA was found to decrease the induction period and the total duration of oscillations. The mechanism underlying these observations was derived mathematically and revealed that inhibition in the methanol oxidation through blockage of active sites was found to further accelerate the intrinsic non-stationarity of the unperturbed system. Altogether, the presented results are among the few concerning the experimental assessment of the sensitiveness of an oscillator towards chemical perturbations. The universal nature of the complex chemical oscillator investigated here might be used for reference when studying the dynamics of other less accessible perturbed networks of (bio)chemical reactions.
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This article analyzes the construction of the African perspective in the General History of Africa project (GHA), focusing on the period between 1965 and 1979. With the participation of over two hundred international experts under the auspices of Unesco, this was one of the greatest intellectual projects of the twentieth century. Based on primary sources, this analysis emphasizes the internal conflicts involved in the construction of the African perspective as a hegemonic line of thought in the GHA. Two critical moments of the project were found in the investigation: the controversial years (1972-78), and the pragmatic years (1978-82). As a result of these disputes, theoretical and methodological parameters were constructed, in addition to eight volumes of material published in the 1980s, and recently republished in Brazil.
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PURPOSE: To indicate orthographic changes to be used as a basic reference for professionals, researchers, doctors, teachers, students and users, which are directly linked and performing activities in health services in general, aimed at implementing the correct orthography in recovery and production of their scientific studies. METHODS: For data collection, were shown some examples of terminology DeCS (Descriptors in Health Science) analyzed according to the current spelling and compared with the Orthographic Vocabulary of Portuguese Language (VOLP). RESULTS: It was select and listed examples of key words and/or terms related to Health Sciences, which was compared to the respective rules of the Orthographic Agreement of Portuguese Language, and divided into three items: graphical accentuation, the non use of dieresis and exceptions and, the use of hyphen. CONCLUSION: This study show some guidelines for the orthographic alterations of the terms used by scientific community, according the new orthographic rules, contributing for the efficiency in the description of the documents and consequently in their recovery.