635 research outputs found

    TRANSFORMAÇÃO ECONÔMICA E HETEROGENEIDADE SOCIAL NA AMÉRICA LATINA

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    This comparative study develop a theoretical-methodological discussionon the concrete conditions for social change, specifically for change in the capital/work relationship. Priorizing a regional perspective which analyses internalas well as external hegemonies and peripheries, the author examines the relationshipbetween the State and industry, defining the State as a new product ofclass relations and, at the same time, a producer of change. The synthesis ofchange in Latin America would be found in the establishment of bases for amass society and the extraordinary expansion and bureaucratization of Stateapparatus, accompanied by emerging social natiional structures.Cette étude comparative développe une discussion théorique-méthodologiquesur les conditions concrètes du changement social, spécifiquement duchangement dans les rapports capital/travail. Choisissant une perspective régionalequi analyse les hégémonies et périphéries tant internes qu’externes, lesauteurs examinent les rapports entre Etat et entreprise, et définissent I’Etatcomme nouveau produit des rapports de classes et en même temps producteurde changements. La synthèse du changement en Amérique Latine se trouveraitdans 1’établissement de bases pour une société de masse et dans I'extraordinaireexpansion et bureaucratization de I'appareil d'Etat, accompagnés de structuressociales nationales émergentes.Este estudo comparativo desenvolve uma discussão teórico-metodológica sobre as condições concretas da mudança social, especificamente da mudança nas relações capital/trabalho. Privilegiando uma vertente regional que analisa hegemonias e periferias tanto internas quanto externas, examina a relação entre Estado e empresa, definindo o Estado como novo produto das relações de classes e ao mesmo tempo produtor de mudança. A síntese das mudanças na América Latina estaria no estabelecimento de bases para uma sociedade de massas e na extraordinária ampliação e burocratízação do aparelho estatal, acompanhados de estruturas sociais nacionais emergentes

    On the use of the gompertz model to predict microbial thermal inactivation under isothermal and non-isothermal conditions

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    Food processes should be designed to provide an adequate margin of safety against microbiological risk of food poisoning and food spoilage throughout shelf life. In this field, the use of mathematical models that describe the microorganisms’ kinetics in such conditions is an important tool for convenient design, control and optimization of efficient processes. If those models are accurate and precise, one can extract the best aiming at predictive purposes. The Gompertz equation is commonly applied to describe sigmoidal kinetics. Besides the proven adequacy of the model in those kinetics descriptions, most of the reported works do not use Gompertz equation in the most convenient form, and insightful information could be obtained with re-parameterized forms. This work aims at reviewing the use of the Gompertz model to describe inactivation, as well as re-parameterized forms that include parameters related to the survival curve features. Microbial survival often presents a shoulder prior to inactivation, followed by a linear phase (corresponding to a maximum inactivation rate) and a tail residual population. The versatility of the Gompertz model in describing kinetics with different shapes, varying from a log-linear tendency till a complete sigmoidal shape, makes it attractive for predictive purposes, both under static and dynamic temperature conditions. Drawbacks and critical features of the model, when it is applied to microbial responses, will be overview.info:eu-repo/semantics/acceptedVersio

    Predictions of microbial thermal inactivation in solid foods: isothermal and non-isothermal conditions

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    This work focuses on the use of the Gompertz-inspired model to predict the thermal inactivation behaviour of microorganisms obtained in solid food products, validated for isothermal and non-isothermal conditions. Experiments were carried out in parsley, artificially inoculated with Listeria innocua. For the isothermal conditions tested, the predictive ability of the model was confined. The higher the temperature, the higher deviations observed (i.e. the model underestimates the inactivation behaviour). However, for the non-isothermal condition tested, the model predicted the microbial response accurately

    Sigmoidal thermal inactivation kinetics of listeria innocua in broth: Influence of strain and growth phase

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    Listeria innocua inactivation was studied within the temperature range 52.5–65.0 ºC, comparing two different strains (10528 and 2030c) and two growth phases (exponential and stationary). Survival curves may present a sigmoidal behaviour, with an initial shoulder (L), followed by a maximum inactivation rate (kmax) period and a final tailing tendency. A Gompertz-inspired model was used to fit experimental data, and kinetic parameters (L, kmax and tail) were estimated by non-linear regression analysis. The influence of temperature, growth phase and strain on kinetic parameters was studied using a 23 factorial experimental design. Results showed that temperature and growth phase were the most significant variables affecting the kinetic parameters. Listeria thermal inactivation varied from a log-linear tendency till a pronounced sigmoidal behaviour, depending on the studied factors

    Influence of pH, type of acid and recovery media on the thermal inactivation of listeria innocua

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    Acidification of foods with organic acids, either by fermentation or by intentional addition, is an important and common mechanism for controlling foodborne pathogens in a diversity of food products. The objective of this work was to study thermal inactivation of Listeria innocua, an acid tolerant microorganism, at 52.5, 60.0 and 65.0 °C, at different pH values (4.5, 6.0 and 7.5), using three types of acid (lactic, acetic and hydrochloric) and three different plating media (Tryptic Soy Agar with 0.6% yeast extract—TSAYE; TSAYE plus 5% NaCl—TSAYE+5%NaCl; and Palcam Agar with selective supplement—Palcam Agar), according to a 34 factorial experimental design. Survival data experimentally obtained were fitted with a Gompertz-inspired model and kinetic parameters (shoulder, maximum inactivation rate—kmax, and tail) were estimated for all conditions considered. The influence of temperature, pH, type of acid and enumeration media on kinetic parameters was assessed. Results showed that, with the exception of the type of acid, all the remaining factors and their combinations significantly affected the shoulder period and kmax. In relation to tail, temperature and recovery media were the affectable factors. It was concluded that the survival of this bacteria is higher when combining low temperature with neutral pH, and when TSAYE is the enumeration medium. Bigelow-inspired models were successfully developed and describe accurately the temperature and pH effects on the kinetic parameters

    The renal and hepatic distribution of Bence Jones proteins depends on glycosylation: A scintigraphic study in rats

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    The aim of the present study was to evaluate renal and liver distribution of two monoclonal immunoglobulin light chains. the chains were purified individually from the urine of patients with multiple myeloma and characterized as lambda light chains with a molecular mass of 28 kDa. They were named BJg (high amount of galactose residues exposed) and BJs (sialic acid residues exposed) on the basis of carbohydrate content. A scintigraphic study was performed on male Wistar rats weighing 250 g for 60 min after iv administration of 1 mg of each protein (7.4 MBq), as the intact proteins and also after carbohydrate oxidation. Images were obtained with a Siemens gamma camera with a high-resolution collimator and processed with a MicroDelta system. Hepatic and renal distribution were established and are reported as percent of injected dose. Liver uptake of BJg was significantly higher than liver uptake of BJs (94.3 vs 81.4%) (P<0.05). This contributed to its greater removal from the intravascular compartment, and consequently lower kidney accumulation of BJg in comparison to BJs (5.7 vs 18.6%) (P<0.05). After carbohydrate oxidation, there was a decrease in hepatic accumulation of both proteins and consequently a higher renal overload. the tissue distribution of periodate-treated BJg was similar to that of native BJs: 82.7 vs 81.4% in the liver and 17.3 vs 18.6% in the kidneys. These observations indicate the important role of sugar residues of Bence Jones proteins for their recognition by specific membrane receptors, which leads to differential tissue accumulation and possible toxicity.UNIV São Paulo,FAC MED,LAB FISIOPATOL RENAL,BR-01246903 São Paulo,SP,BRAZILUNIV São Paulo,CTR MED NUCL,BR-05403010 São Paulo,SP,BRAZILUNIV São Paulo,HOSP CLIN,SERV RADISISOTOPOS,BR-05403000 São Paulo,SP,BRAZILUniversidade Federal de São Paulo,MOL BIOL LAB,BR-04024900 São Paulo,SP,BRAZILUniversidade Federal de São Paulo,MOL BIOL LAB,BR-04024900 São Paulo,SP,BRAZILWeb of Scienc

    Heat inactivation of Listeria innocua in broth and food products under non-isothermal conditions

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    The objective of this work was to study the effect of three linear temperature profiles (heating rates of 1.5, 1.8 and 2.6 °C/min, from 20 to 65 °C) on Listeria innocua inactivation in liquid medium. The inactivation was also analyzed in artificially contaminated parsley (heating rate of 1.8 °C/min) and throughout a frying process, using a pre-cooked frozen food as case study. Inactivation showed a sigmoidal behaviour and all data was fitted with a Gompertz-inspired model. Results demonstrated that, in liquid media, Listeria inactivation is influenced by the temperature profile used. As heating rate increases, the shoulder decreases and the tail effect disappears. If Listeria was in parsley, its heat resistance increased (for identical experimental conditions in broth). Besides model adequacy was proven in all studied situations, the heating rate affected parameters’ precision.info:eu-repo/semantics/acceptedVersio

    Anuloplastia mitral com tira de pericárdio bovino resultados de 18 anos

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    PURPOSE: Prosthetic annuloplasty rings are currently used in mitral reconstruction. Posterior annuloplasty with a bovine pericardial strip is a technique largely used in the Heart Institute of University of São Paulo Medical School. The purpose of the study was to analyze the late results of mitral valve repair with posterior annuloplasty using a bovine pericardial strip. METHODS: Between January 1984 and December 2002, 273 patients underwent mitral valve repair with posterior pericardial annuloplasty in the Heart Institute of University of São Paulo Medical School. One hundred and forty four (52.7%) were women and ages ranged between 1 and 76 years (38.3 ± 21.1). Rheumatic fever was present in 52.0% of the patients. Associated techniques were employed in 26.0% of the patients, and the most frequent was chordal shortening (9.2%). RESULTS: Hospital mortality was 3.3% (9 patients), with the major cause being low cardiac output (6 patients). Actuarial survival was 55.1% ± 16.8% in 18 years. During the 18-year follow-up: patients were free from the following: reoperation (59.1% ±± 13.9%, (percent +/- Standard Error), thromboembolism (97.4% ± 2.3%), hemolysis (99.2% ± 0.2%), and endocarditis (99.6% ± 1.0%). In the late follow-up period, 83.9% were classified as New York Heart Association functional class I. CONCLUSIONS: Late results with mitral valve repair with posterior annuloplasty using a bovine pericardial strip were satisfactory. The technique is feasible, reproducible, and cost effective.OBJETIVO: Anéis protéticos para anuloplastia são usados nas plásticas da valva mitral de forma rotineira. A anuloplastia posterior com tira de pericárdio bovino é uma técnica largamente utilizada no Instituto do Coração - HC - FMUSP. O objetivo deste estudo foi analisar os resultados tardios da plástica da valva mitral com a utilização desta técnica na nossa instituição. MÉTODOS: Entre janeiro de 1984 e dezembro de 2002, 273 pacientes foram submetidos a plástica da valva mitral com anuloplastia posterior no Instituto do Coração. Foram excluídos os pacientes submetidos a outros procedimentos no anel posterior. Cento e quarenta e quatro (52,7%) eram do sexo feminino e a idade variou entre 1 e 76 anos (média: 38,3 ± 21,1 anos). Em 52% dos pacientes, havia história de febre reumática. Técnicas associadas para reconstrução valvar foram empregadas em 26% dos casos, sendo a mais utilizada, o encurtamento de cordas (9,2%). RESULTADOS: A mortalidade hospitalar foi de 3,3% (9 casos). A principal causa de óbito foi baixo débito cardíaco (6 pacientes). A sobrevida actuarial foi de 55,1 ± 16,8% (percent +/- Standard Error) em 18 anos, sobrevida livre de reoperação, tromboembolismo, hemólise e endocardite foram respectivamente de 59,1 ± 13,9%, 97,4 ± 2,3%, 99,2 ± 0,2%, 99,6 ± 1,0% em 18 anos. No seguimento tardio, 83,9% dos pacientes se encontravam em classe funcional I (NYHA). CONCLUSÕES: Concluímos que os resultados tardios foram satisfatórios. A técnica é fácil, reprodutível e de baixo custo

    3D microsimulation of milkruns and pickers in warehouses using SIMIO

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    To help the Bosch Car Multimedia Portugal in Ferreiros, Braga to reduce its costs (both in time and space) with its warehouse, a micro simulation model is being developed in Simio. Particularly, the tool needs to be able to model pickers riding milkruns to collect containers of products, from a warehouse, to satisfy the needs of the production lines. In this sense, the storage strategy used on the warehouse, the quantity of requests a picker gets per shift, the time between shifts, the number of types of products, the arrival rate of requests, and the number of milkruns and pickers needs to be adjustable. Additionally, to design the corridors of the warehouse in a configurable way, an Add-in in C#, using the API of Simio, is being developed. Thus, this paper intends to document the first part of the simulation model developed, which consists on the pickers receiving requests and riding their milkruns to collect the respective containers from the warehouse. Five different Simio models compose the main simulation model. Conclusions and future work are discussed.This work has been co-supported by SI I&DT project in joint-promotion nº 36265/2013 (HMIEXCEL - 2013-2015 Project) and by FCT – Fundação para a Ciência e Tecnologia in the scope of the project: PEst-OE/EEI/UI0319/2014

    Spatial and temporal patterns of occurrence of lutzomyia sand fly species in an endemic area for cutaneous leishmaniasis in the Atlantic forest region of northeast Brazil

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    Sand fly populations of different ecological niches in the Amaraji endemic American Cutaneous Leishmaniasis (ACL) focus of the Pernambuco Atlantic Forest region of northeastern Brazil were monitored spatiotemporally. Lutzomyia whitmani was dominant in all niches but occurred in smaller numbers in forested locations. L. whitmani was significantly less seasonal than the other species, being present throughout the year while other species were more abundant between February and April. These results suggest that L. whitmani may potentially be the principal vector of ACL in the region, even though the sand fly fauna was diverse: 88% were L.whitmani and 12% belonged to 11 other species. Two other species, L. complexa (1.3%) and L. migonei (0.8%), considered to be ACL vectors in other regions, were also present. This detailed picture of the sand fly population's abundance and spatiotemporal distribution provides a basis for future modeling studies of forecasting sand fly activity patterns and ACL occurence361Sand fly research and controlS71S76CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ410481/2006-
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