72 resultados para ANALYTIC ULTRACENTRIFUGATION


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This study examines the relationship between management accounting and planning profiles in Brazilian companies. The main goal is to understand the consequences of not including a fully structured management accounting scheme in the planning process. The authors conducted a field research among medium and large-sized companies, using a probabilistic sample from a population of 2281 companies. Using analytic hierarchy process (AHP) and statistical cluster analysis, the authors grouped the entities` strategic budget planning processes into five profiles, after which the authors applied statistical tests to assess the five clusters. The study concludes that poor or fully implemented strategic and budget-planning processes relate to the management accounting profiles of the Brazilian organizations studied. (C) 2009 Elsevier Inc. All rights reserved.

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We study the existence of asymptotically almost periodic classical solutions for a class of abstract neutral integro-differential equation with unbounded delay. A concrete application to partial neutral integro-differential equations which arise in the study of heat conduction in fading memory material is considered. (C) 2011 Elsevier Inc. All rights reserved.

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Bothropstoxin-I (BthTx-I), a Lys49-PLA(2) from Bothrops jararacussu venom, permeabilizes membranes by a non-hydrolytic Ca(2+)-independent mechanism. The BthTx-I showed activity against liposomes including 10% and 50% negatively charged lipids at pH 7.0, but not at pH 5.0. Nevertheless, ultracentrifugation and FRET demonstrated that at pH 5.0 the BthTx-I is bound to 50% negatively charged membranes. ANS binding identified a non-native monomeric conformation at pH 5.0, suggesting that tertiary structure alterations result in activity loss of the BthTx-I at low pH. (C) 2009 Elsevier Ltd. All rights reserved.

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We discuss the existence of mild, classical and strict solutions for a class of abstract differential equations with nonlocal conditions. Our technical approach allows the study of partial differential equations with nonlocal conditions involving partial derivatives or nonlinear expressions of the solution. Some concrete applications to partial differential equations are considered. (C) 2010 Elsevier Ltd. All rights reserved.

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In this paper we discuss the existence of alpha-Holder classical solutions for non-autonomous abstract partial neutral functional differential equations. An application is considered.

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Objective-To evaluate the presence of a dominance rank in a group of cats and the relation between agonistic behavior and the use of resources, including environmental enrichment, in these cats. Design-Observational analytic study. Animals-27 neutered cats in a shelter in Sao Paulo, Brazil. Procedures-The cats were video recorded for 4 consecutive days to obtain baseline data. Subsequently, a puzzle feeder was added as an enrichment device every other day over 8 days, for a total of 4 days with enrichment. Cats were also video recorded on these days. All pretreatment and posttreatment agonistic behaviors and interactions with the puzzle feeder were recorded by reviewing the videotapes. Results-143 agonistic encounters were recorded, of which 44 were related to resources and 99 were not. There were insufficient agonistic interactions to determine a dominance rank. Presence or absence of the puzzle feeder did not affect the rate of aggression. There was no significant effect of weight, sex, or coat color on the rate of aggression, and aggressive behavior did not correlate with time spent with the puzzle feeder. Twenty-three of the 27 cats interacted with the puzzle feeder. Conclusions and Clinical Relevance-In a stable group of communally housed cats, environmental enrichment did not cause increased aggression as a result of competition for the source of enrichment. Because environmental enrichment increases the opportunity to perform exploratory behaviors, it may improve the welfare of groups of cats maintained long-term in shelters, sanctuaries, or multicat households. (J Am Vet Med Assoc 2011239:796-802)

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Little attention has been given to the contextual politics of service delivery reforms. By focusing on cases of reform in the healthcare sector and, to a lesser extent, in the main policies in the social service sector in India, Mexico and Brazil, this article explores two dimensions of analysis which have enormous relevance in understanding the reach and effectiveness of service delivery reforms: (1) the historical timing of reforms and sectorial baselines, and (2) the degree and institutional locus of local discretion in policy. Findings show that depending on both dimensions, there is an extraordinary variation as to the degree, interests involved and meaning of changes which, in theory, correspond to these countries` commitment to the service delivery reforms, However, consideration of the contextual politics is relevant not for the sake of diversity but for the similarities that this diversity reveals, pointing to underlying analytic dimensions that receive attention in this article.

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Introduction: A variety of subjective experiences have been reported to be associated with the symptom expression of obsessive-compulsive disorder (OCD) and Tourette syndrome (TS). First described in TS patients, these subjective experiences have been defined in different ways. There is no consensus in the literature on how to best define subjective experiences. This lack of consensus may hinder the understanding of study results and prevents the possibility of including them in the search for etiological factors associated with OCD and TS. Methods: The objective of this article was to review the descriptions of subjective experiences in the English-language literature from 1980-2007. This meta-analytic review was carried out using the English-language literature from 1980-2007 available on MEDLINE, PsycINFO, and the Cochrane Library databases using the following search terms: premonitory urges, sensory tics, ""just-right"" perceptions, sensory phenomena, sensory experiences, incompleteness, ""not just-right"" phenomena, obsessive-compulsive disorder and TS, including OCD and/or TS, in all combination searches. We also searched for the references cited in each article previously found that referred to the aforementioned terms. Thirty-one articles were included in the study. Results: Subjective experiences, in particular, the sensory phenomena, were important phenotypic variables in the characterization of the tic-related OCD subtype and were more frequent in the early-onset OCD subtype. There is a paucity of studies using structured interviews to assess sensory phenomena, their epidemiology and the etiological mechanisms associated with sensory phenomena. Conclusion: The current review provides some evidence that sensory phenomena can be useful to identify more homogenous subgroups of OCD and TS patients and should be included as important phenotypic variables in future clinical, genetic, neuroimaging, and treatment-response studies.

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Conventional karyotyping detects anomalies in 3-15% of patients with multiple congenital anomalies and mental retardation (MCA/MR). Whole-genome array screening (WGAS) has been consistently suggested as the first choice diagnostic test for this group of patients, but it is very costly for large-scale use in developing countries. We evaluated the use of a combination of Multiplex Ligation-dependent Probe Amplification (MLPA) kits to increase the detection rate of chromosomal abnormalities in MCA/MR patients. We screened 261 MCA/MR patients with two subtelomeric and one microdeletion kits. This would theoretically detect up to 70% of all submicroscopic abnormalities. Additionally we scored the de Vries score for 209 patients in an effort to find a suitable cut-off for MLPA screening. Our results reveal that chromosomal abnormalities were present in 87 (33.3%) patients, but only 57 (21.8%) were considered causative. Karyotyping detected 15 abnormalities (6.9%), while MLPA identified 54 (20.7%). Our combined MLPA screening raised the total detection number of pathogenic imbalances more than three times when compared to conventional karyotyping. We also show that using the de Vries score as a cutoff for this screening would only be suitable under financial restrictions. A decision analytic model was constructed with three possible strategies: karyotype, karyotype + MLPA and karyotype + WGAS. Karyotype + MLPA strategy detected anomalies in 19.8% of cases which account for 76.45% of the expected yield for karyotype + WGAS. Incremental Cost Effectiveness Ratio (ICER) of MLPA is three times lower than that of WGAS, which means that, for the same costs, we have three additional diagnoses with MLPA but only one with WGAS. We list all causative alterations found, including rare findings, such as reciprocal duplications of regions deleted in Sotos and Williams-Beuren syndromes. We also describe imbalances that were considered polymorphisms or rare variants, such as the new SNP that confounded the analysis of the 22q13.3 deletion syndrome. (C) 2011 Elsevier Masson SAS. All rights reserved.

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PURPOSE: To propose an analytic framework for ocular fundus alterations in late-stage Vogt,Koyanagi-Harada (VKH) disease, to describe the characteristics of overall retinal function as measured with full field electroretinography (ERG), and to correlate the intensity of the fundus changes with full-field ERG alterations and to stratify patients accordingly. DESIGN: Cross-sectional case series. METHODS: Forty-seven eyes of 26 patients with late, stage VKH disease (> 6 months past disease onset) followed-up at the University of Sao Paulo School of Medicine underwent fundus photography within 2 months of a full,field ERG examination, both according to pre-defined protocols. Fundus pictures were evaluated by two observers regarding diffuse fundus depigmentation, nummular lesions, pigment clumps, and subretinal fibrosis, and an overall analysis classified the fundus changes as mild, moderate, or severe. Full field ERG results were analyzed according to fundus-based stratification and also were stratified into 3 groups solely on the basis of decreasing amplitudes (ERG based or cluster stratification). The concordance between fundus-based and full-field ERG-based stratification strategies was estimated. RESULTS: Overall fundus grading showed substantial interobserver concordance (kappa = 0.78). Comparison of full field ERG parameters of the three fundus based stratified groups showed diffusely diminished amplitudes with preservation of implicit times (P < .05). Fundus-based and full-field ERG-based stratification strategies also showed substantial concordance (kappa = 0.68). CONCLUSIONS: The analytic framework for fundus findings proposed in this study seems reproducible and useful, because the severity categories do correlate with retinal function as measured by full-field ERG. This system may allow more precise exchange of information between practitioners as well as researchers with regard to identifying patients with greater retinal compromise rapidly as well as in comparison of outcomes of different treatment regimens. (Am J Ophthalmol 2009;148: 939-945. (C) 2009 by Elsevier Inc. All rights reserved.)

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Background/Objectives: Vitamin A deficiency (VAD) is a world public health problem contributing to the increase in childhood morbidity and mortality in developing countries and severe deficiency of vitamin A may lead to xerophthalmia and blindness. The objective of this study was to determine the prevalence of VAD among Brazilian school-aged children attended at a primary health unit and to verify if some considered risk factor was associated with VAD in this group. Subjects/Methods: A descriptive prospective transverse study was conducted on 103 randomly selected children. A total of 54 boys and 49 girls aged 5.5-11 years had the relative dose-response (RDR) test performed on. Possible ocular alterations related to vitamin A and the status of anemia, serum zinc, some acute-phase proteins, and anthropometric situation were determinate by an analytic design. Results: No child presented xerophthalmia. Serum retinol values lower than 1.05 and 0.7 mu moll(-1), respectively were found in 26.2 and 5.8% of the children. The prevalence of hypovitaminosis detected by RDR test was 20.4%. The following variables and their relationship with VAD were evaluated: sex (P = 0.33; 95% confidence interval 0.61-4.34), weight and height (P >= 0.5), hemoglobin (P = 0.15), C-reactive protein (P = 0.56; 95% confidence interval 0.75-18.26), alpha-1-acid-glycoprotein (P = 0.56; 95% confidence interval 0.15-15.42) and serum zinc (P = 0.31). None of these variables was related to VAD. Conclusions: In this population, the prevalence of VAD detected could be considered a public health problem. School-aged children can be considered at risk for VAD mainly of a subclinical level, even without some associated risk factors.

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Background: Oxidative modification of low-density lipoprotein (LDL) plays a key role in the pathogenesis of atherosclerosis. LDL(-) is present in blood plasma of healthy subjects and at higher concentrations in diseases with high cardiovascular risk, such as familial hypercholesterolemia or diabetes. Methods: We developed and validated a sandwich ELISA for LDL(-) in human plasma using two monoclonal antibodies against LDL(-) that do not bind to native LDL, extensively copper-oxidized LDL or malondialdehyde-modified LDL. The characteristics of assay performance, such as limits of detection and quantification, accuracy, inter- and intra-assay precision were evaluated. The linearity, interferences and stability tests were also performed. Results: The calibration range of the assay is 0.625-20.0 mU/L at 1: 2000 sample dilution. ELISA validation showed intra- and inter- assay precision and recovery within the required limits for immunoassays. The limits of detection and quantification were 0.423 mU/L and 0.517 mU/L LDL(-), respectively. The intra- and inter- assay coefficient of variation ranged from 9.5% to 11.5% and from 11.3% to 18.9%, respectively. Recovery of LDL(-) ranged from 92.8% to 105.1%. Conclusions: This ELISA represents a very practical tool for measuring LDL(-) in human blood for widespread research and clinical sample use. Clin Chem Lab Med 2008; 46: 1769-75.

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We discuss the basic hydrodynamics that determines the density structure of the disks around hot stars. Observational evidence supports the idea that these disks are Keplerian (rotationally supported) gaseous disks. A popular scenario in the literature, which naturally leads to the formation of Keplerian disks, is the viscous decretion model. According to this scenario, the disks are hydrostatically supported in the vertical direction, while the radial structure is governed by the viscous transport. This suggests that the temperature is one primary factor that governs the disk density structure. In a previous study we demonstrated, using three-dimensional non-LTE Monte Carlo simulations, that viscous Keplerian disks can be highly nonisothermal. In this paper we build on our previous work and solve the full problem of the steady state nonisothermal viscous diffusion and vertical hydrostatic equilibrium. We find that the self-consistent solution departs significantly from the analytic isothermal density, with potentially large effects on the emergent spectrum. This implies that nonisothermal disk models must be used for a detailed modeling of Be star disks.

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The theory of diffusion in many-dimensional Hamiltonian system is applied to asteroidal dynamics. The general formulation developed by Chirikov is applied to the NesvornA1/2-Morbidelli analytic model of three-body (three-orbit) mean-motion resonances (Jupiter-Saturn-asteroid). In particular, we investigate the diffusion along and across the separatrices of the (5, -2, -2) resonance of the (490) Veritas asteroidal family and their relationship to diffusion in semi-major axis and eccentricity. The estimations of diffusion were obtained using the Melnikov integral, a Hadjidemetriou-type sympletic map and numerical integrations for times up to 10(8) years.

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We investigate the impact of the existence of a primordial magnetic field on the filter mass, characterizing the minimum baryonic mass that can form in dark matter (DM) haloes. For masses below the filter mass, the baryon content of DM haloes are severely depressed. The filter mass is the mass when the baryon to DM mass ratio in a halo is equal to half the baryon to DM ratio of the Universe. The filter mass has previously been used in semi-analytic calculations of galaxy formation, without taking into account the possible existence of a primordial magnetic field. We examine here its effect on the filter mass. For homogeneous comoving primordial magnetic fields of B(0) similar to 1 or 2 nG and a re-ionization epoch that starts at a redshift z(s) = 11 and is completed at z(r) = 8, the filter mass is increased at redshift 8, for example, by factors of 4.1 and 19.8, respectively. The dependence of the filter mass on the parameters describing the re-ionization epoch is investigated. Our results are particularly important for the formation of low-mass galaxies in the presence of a homogeneous primordial magnetic field. For example, for B(0) similar to 1 nG and a re-ionization epoch of z(s) similar to 11 and z(r) similar to 7, our results indicate that galaxies of total mass M similar to 5 x 108 M(circle dot) need to form at redshifts z(F) greater than or similar to 2.0, and galaxies of total mass M similar to 108 M(circle dot) at redshifts z(F) greater than or similar to 7.7.