977 resultados para Variable Neighborhood Search
Resumo:
There has been increased recognition of the importance of developing diabetes self-management education (DSME) interventions that are effective with under-served and minority populations. Despite several recent studies in this area, there is to our knowledge no systematic review or synthesis of what has been learned from this research. An electronic literature search identified five formative evaluations and ten controlled DSME intervention trials focused on under-served (low-income, minority or aged) populations. The RE-AIM (Reach, Efficacy, Adoption, Implementation, Maintenance) evaluation framework was used to evaluate the controlled studies on the dimensions of reach, efficacy, adoption, implementation, and maintenance. Fifty percent of the studies identified reported on the percentage of patients who participated, and the percentages were highly variable. The methodological quality of the articles was generally good and the short-term results were encouraging, especially on behavioral outcomes. Data on adoption (representativeness of settings and clinicians who participate) and implementation were almost never reported. Studies of modalities in addition to group meetings are needed to increase the reach of DSME with under-served populations. The promising formative evaluation work that has been conducted needs to be extended for more systematic study of the process of intervention implementation and adaptation with special populations. Studies that explicitly address the community context and that address multiple issues related to public health impact of DSME interventions are recommended to enhance long-term results. Copyright (C) 2002 John Wiley Sons, Ltd.
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Two families, originally diagnosed as having nonsyndromic X-linked mental retardation (NSXLMR), were reviewed when it was shown that they had a 24-bp duplication (428-45 1dup(24bp)) in the ARX gene [Stromme et al., 2002: Nat Genet 30:441-445]. This same duplication had also been found in three other families: one with X-linked infantile spasms and hypsarrhythmia (X-linked West syndrome, MIM 308350) and two with XLMR and dystonic movements of the hands (Partington syndrome, MIM 309510). On review, manifestations of both West and Partington syndromes were found in some individuals from both families. In addition, it was found that one individual had autism and two had autistic behavior, one of whom had epilepsy. The degree of mental retardation ranged from mild to severe. A GCG trinucleotide expansion (GCG)10+7 and a deletion of 1,517 by in the ARX gene have also been found in association with the West syndrome, and a missense mutation (1058C >T) in a family with a newly recognized form of myoclonic epilepsy, severe mental retardation, and spastic paraplegia [Scheffer et al., 2002: Neurology, in press]. Evidently all these disorders are expressions of mutations in the same gene. It remains to be seen what proportions of patients with infantile spasms, focal dystonia, autism, epilepsy, and nonsyndromic mental retardation are accounted for by mutations in the ARX gene. (C) 2002 Wiley-Liss, Inc.
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This paper analyzes the geography of regional competitiveness in manufacturing in Brazil. The authors estimate stochastic frontiers to calculate regional efficiency of representative firms in 137 regions in the period 2000-2006, in four sectors defined by technological intensity. The efficiency results are analyzed using Markov Spatial Transition Matrices to provide insights into the transition of regions between efficiency levels, considering their local spatial context. The results indicate that geography plays an important role in manufacturing competitiveness. In particular, regions with more competitive neighbors are more likely to improve their relative efficiency (pull effect) over time, and regions with less competitive neighbors are more likely to lose relative efficiency (drag effect). The authors find that the pull effect is stronger than the drag effect.
Resumo:
Managing a variable demand scenario is particularly challenging on services organizations because services companies usually have a major part of fixed costs. The article studies how a services organization manages its demand variability and its relation with the organization`s profitability. Moreover, the study searched for alternatives used to reduce the demand variability`s impact on the profitability of the company. The research was based on a case study with a Brazilian services provider on information technology business. The study suggests that alternatives like using outsourced employees to cover demand peaks may bring benefits only on short term, reducing the profitability of the company on long term: Some options are revealed, like the internationalization of employees and the investment on developing its own workforce.
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Background: Familial partial epilepsy with variable foci (FPEVF) is an autosomal dominant syndrome characterized by partial seizures originating from different brain regions in different family members in the absence of detectable structural abnormalities. A gene for FPEVF was mapped to chromosome 22q12 in two distantly related French-Canadian families. Methods: We describe the clinical features and performed a linkage analysis in a Spanish kindred and in a third French-Canadian family distantly related to the original pedigrees. Results: Onset of seizures was typically in middle childhood, and attacks were usually easy to control. Seizure semiology varied among family members but was constant for each individual. In some, a pattern of nocturnal frontal lobe seizures led to consideration of the diagnosis of autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE). The Spanish family was mapped to chromosome 22q (multipoint lod score, 3.4), and the new French-Canadian family had a multipoint lod score of 2.97 and shared the haplotype of the original French-Canadian families. Conclusions: Identification of the various forms of familial partial epilepsy is challenging, particularly in small families, in which insufficient individuals exist to identify a specific pattern. We provide clinical guidelines for this task, which will eventually be supplanted by specific molecular diagnosis. We confirmed linkage of FPEVF to chromosome 22q 12 and redefined the region to a 5.2-Mb segment of DNA.
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Larval quality may be capable of explaining much of the variation in the recruitment and subsequent population dynamics of benthic marine invertebrates. Whilst the effects of larval nutritional condition on adult performance have received the most attention, recent work has shown that larval size may also be an important and ubiquitous source of variation in larval quality. We examined the effects of variation in larval size on the post-metamorphic survival and growth of Watersipora subtorquata in 2 very different habitats - experimental substrata and pier pilings. We found strong effects of larval size on colony performance, although these varied among experiments. For colonies on experimental substrata, larval size positively affected adult survival and, initially, growth. However, after 3 wk in the field, there was no relationship between larval size and colony size, possibly because colonies were completely surrounded by newly settled organisms. Larval size also positively affected post-metamorphic growth of colonies on pier pilings, but, surprisingly, colonies that came from larger larvae had lower survival than colonies from smaller larvae. Overall, variation in larval size will strongly affect the recruitment and subsequent performance of adults in this species, although this may vary among different habitats. This study highlights the importance of examining the effects of larval quality on adult performance in as realistic conditions as possible, because of the strong interaction between larval size effects and the environment.
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Ohman and colleagues provided evidence for preferential processing of pictures depicting fear-relevant animals by showing that pictures of snakes and spiders are found faster among pictures of fiowers and mushrooms than vice versa and that the speed of detecting fear-relevant animals was not affected by set size whereas the speed of detecting fiowers/mushrooms was. Experiment 1 replicated this finding. Experiment 2, however, found similar search advantages when pictures of cats and horses or of wolves and big cats were to be found among pictures of flowers and mushrooms. Moreover, Experiment 3, in a within subject comparison, failed to find faster identification of snakes and spiders than of cats and horses among flowers and mushrooms. The present findings seem to indicate that previous reports of preferential processing of pictures of snakes and spiders in a visual search task may reflect a processing advantage for animal pictures in general rather than fear-relevance.
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The image reconstruction using the EIT (Electrical Impedance Tomography) technique is a nonlinear and ill-posed inverse problem which demands a powerful direct or iterative method. A typical approach for solving the problem is to minimize an error functional using an iterative method. In this case, an initial solution close enough to the global minimum is mandatory to ensure the convergence to the correct minimum in an appropriate time interval. The aim of this paper is to present a new, simple and low cost technique (quadrant-searching) to reduce the search space and consequently to obtain an initial solution of the inverse problem of EIT. This technique calculates the error functional for four different contrast distributions placing a large prospective inclusion in the four quadrants of the domain. Comparing the four values of the error functional it is possible to get conclusions about the internal electric contrast. For this purpose, initially we performed tests to assess the accuracy of the BEM (Boundary Element Method) when applied to the direct problem of the EIT and to verify the behavior of error functional surface in the search space. Finally, numerical tests have been performed to verify the new technique.
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The main focus of this essay is the first American round-the-world scientific voyage, the U. S Exploring Expedition, which took place between 1838 and 1841 and was lead by Lieutenant Charles Wilkes. Here, I discuss the purposes of this expedition in the context of the voyages of circumnavigation accomplished by the various European powers during the same period.
Resumo:
Chronic beryllium disease (CBD) is clinically similar to other granulomatous diseases such as sarcoidosis. It is often misdiagnosed if a thorough occupational history is not taken. When appropriate, a beryllium lymphocyte proliferation tests (BeLPT) need to be performed. We aimed to search for CBD among currently diagnosed pulmonary sarcoidosis patients and to identify the occupations and exposures in Ontario leading to CBD. Questionnaire items included work history and details of possible exposure to beryllium. Participants who provided a history of previous work with metals underwent BeLPTs and an ELISPOT on the basis of having a higher pretest probability of CBD. Among 121 sarcoid patients enrolled, 87 (72%) reported no known previous metal dust or fume exposure, while 34 (28%) had metal exposure, including 17 (14%) with beryllium exposure at work or home. However, none of these 34 who underwent testing had positive test results. Self-reported exposure to beryllium or metals was relatively common in these patients with clinical sarcoidosis, but CBD was not confirmed using blood assays in this population.
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PHWAT is a new model that couples a geochemical reaction model (PHREEQC-2) with a density-dependent groundwater flow and solute transport model (SEAWAT) using the split-operator approach. PHWAT was developed to simulate multi-component reactive transport in variable density groundwater flow. Fluid density in PHWAT depends not on only the concentration of a single species as in SEAWAT, but also the concentrations of other dissolved chemicals that can be subject to reactive processes. Simulation results of PHWAT and PHREEQC-2 were compared in their predictions of effluent concentration from a column experiment. Both models produced identical results, showing that PHWAT has correctly coupled the sub-packages. PHWAT was then applied to the simulation of a tank experiment in which seawater intrusion was accompanied by cation exchange. The density dependence of the intrusion and the snow-plough effect in the breakthrough curves were reflected in the model simulations, which were in good agreement with the measured breakthrough data. Comparison simulations that, in turn, excluded density effects and reactions allowed us to quantify the marked effect of ignoring these processes. Next, we explored numerical issues involved in the practical application of PHWAT using the example of a dense plume flowing into a tank containing fresh water. It was shown that PHWAT could model physically unstable flow and that numerical instabilities were suppressed. Physical instability developed in the model in accordance with the increase of the modified Rayleigh number for density-dependent flow, in agreement with previous research. (c) 2004 Elsevier Ltd. All rights reserved.
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P>Background: Many patients with common variable immunodeficiency (CVID) have a clinical history suggestive of allergic respiratory disease. However, in such individuals, the prevalence of asthma and the role of atopy have not been well established. The objective of this study was to evaluate pulmonary function and identify asthma in patients with CVID. We also investigated the role of IgE as a trigger of asthma in these patients. Methods: Sixty-two patients diagnosed with CVID underwent spirometry, as well as skin prick testing and in vitro determination of serum-specific IgE levels for aeroallergens, together with bronchial provocation with histamine and allergen. Results: The most common alteration identified through spirometry was obstructive lung disease, which was observed in 29 (47.5%) of the 62 patients evaluated. Eighteen (29.0%) of the 62 patients had a clinical history suggestive of allergic asthma. By the end of the study, asthma had been diagnosed in nine (14.5%) patients and atopy had been identified in six (9.7%). In addition, allergic asthma had been diagnosed in four patients (6.5% of the sample as a whole; 22.2% of the 18 patients with a clinical history suggestive of the diagnosis). Conclusion: In this study, CVID patients testing negative for specific IgE antibodies and suspected of having allergic asthma presented a positive response to bronchial provocation tests with allergens. To our knowledge, this is the first such study. When CVID patients with a history suggestive of allergic asthma test negative on traditional tests, additional tests designed to identify allergic asthma might be conducted.
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H-1 NMR spectra of the thyroid hormone thyroxine recorded at low temperature and high field show splitting into two peaks of the resonance due to the H2,6 protons of the inner (tyrosyl) ring. A single resonance is observed in 600 MHz spectra at temperatures above 185 K. An analysis of the line shape as a function of temperature shows that the coalescence phenomenon is due to an exchange process with a barrier of 37 kJ mol(-1). This is identical to the barrier for coalescence of the H2',6' protons of the outer (phenolic) ring reported previously for the thyroid hormones and their analogues. It is proposed that the separate peaks at low temperature are due to resonances for H2,6 in cisoid and transoid conformers which are populated in approximately equal populations. These two peaks are averaged resonances for the individual H2 and H6 protons. Conversion of cisoid to transoid forms can occur via rotation of either the alanyl side chain or the outer ring, from one face of the inner ring to the other. It is proposed that the latter process is the one responsible for the observed coalescence phenomenon. The barrier to rotation of the alanyl side chain is greater than or equal to 37 kJ mol(-1), which is significantly larger than has previously been reported for Csp(2)-Csp(3) bonds in other Ph-CH2-X systems. The recent crystal structure of a hormone agonist bound to the ligand-binding domain of the rat thyroid hormone receptor (Wagner et al. Nature 1995, 378, 690-697) shows the transoid form to be the bound conformation. The significant energy barrier to cisoid/transoid interconversion determined in the current study combined with the tight fit of the hormone to its receptor suggests that interconversion between the forms cannot occur at the receptor site but that selection for the preferred bound form occurs from the 50% population of the transoid form in solution.