59 resultados para OFA
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A função social da empresa e, a finalidade do instituto da falência, são analisadas perante os reais interesses da coletividade na preservação dos empreendimentos que, embora bons irradiadores de beneficios sociais e econômicos à comunidade, enfrentam dificuldades financeiras. Diversas formas de como conduzir a gestão administrativa da empresa, enquanto beneficiária da proteção legal, são contempladas e, sugerida a adoção de uma gestão reconstrutiva, focada na recuperação da empresa enquanto beneficio ao conjunto da coletividade.
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The reduction of standard weekly working hours from the curreilt leveI of 44 hours to 40 hours has recently been proposed by the main central unions as a way to create jobs and reduce unemployment in Brazil. The idea, known as work-sharing, is that the reduction in average hours per worker allows the same tasks to be performed bymore employees. However, the notion ofwork-sharing has been challenged by the theoretical and the empirical literature. Theory says that, in general, a reduction in the duration ofthe workweek tends to decrease employment. Work-sharing is even less likely in the case of no wage restraint, when monthly wages are not proportionally reduced. Recent cautious econometric evidence also conflict with the notion of work -sharing (Hunt, 1999, and Crépon and Kramarz, 2000). The objective ofthis paper is to study the effects ofthe workweek length reduction from 48 to 44 hours, prescribed by the 1988 Constitutional change, on the Brazilian labor market. We find that: i) the reduction of standard working hours was followed by a significant decrease in actual working hours: 60,7% ofthe employees that worked between 45 and 48 weekly hours in 1988 (the affected group) and that remained employed in 1989 switched to a 40-44 hours workweek; ii) belonging to the affected group in 1988 had no statistical effect on the probability ofbecoming unemployed, exiting the labor market, or switching to an informal job in 1989; iii) the reduction in working hours implied a 8,8% increase in hourly real wages with respect to those that remained employed at 40-44 hours a week. In sum, the reduction of standard working hours in 1988 reduced actual working hours, did not affect the probability ofa typical worker to lose hisjob in 1989, and implied a relative increase in hourly real wages.
Efeitos da utilização de diferentes covariáveis na avaliação do ganho de peso médio diário em suínos
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The sun mushroom is the popular name for the Agaricus blazei Murill fungus, a mushroom native to south-eastern Brazil, which has been frequently used in popular medicine mainly in the form of tea to treat various ailments (stress, diabetes, etc.). In the present study, the genotoxic and/or anti-genotoxic effects ofA. blazei on mammalian cells in culture was assessed by checking the increase or reduction of micronucleus (MN) frequency and comets. The sun mushroom (lineage 99/26) was used as aqueous extracts prepared (2.5%) at three different temperatures (60, 25 and 4°C). The in vitro micronucleus (MN) test in binucleated cells and comet assay were used in V79 cells cultivated in HAM-F10+DMEM medium (1:1), supplemented with 10% of fetal bovine serum. The experiments were divided into four treatment types: 1. Negative control; 2. Positive control with MMS; 3. Treatments with the three forms of extracts (60, 25 and 4°C); and 4. Treatments with the extracts in different associations (simultaneous, pre-treatment, post-treatment and simultaneous after pre-incubation for 1 h) with MMS. None of the A. blazei extracts show genotoxic activity. In the comet assay no protecting effect was found. The results obtained in the MN test showed that the three forms of extracts used had protective activity, suggesting that the compound or active ingredients of A. blazei are always present in these extracts. The greater protective efficiency of the simultaneous treatment and simultaneous treatment with pre-incubation mixture with MMS suggests that the extracts have an antimutagenic action of the desmutagenic type. © 2002 Elsevier Science Ltd. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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This PhD thesis describes the application of some instrumental analytical techniques suitable to the study of fundamental food products for the human diet, such as: extra virgin olive oil and dairy products. These products, widely spread in the market and with high nutritional values, are increasingly recognized healthy properties although their lipid fraction might contain some unfavorable components to the human health. The research activity has been structured in the following investigations: “Comparison of different techniques for trans fatty acids analysis” “Fatty acids analysis of outcrop milk cream samples, with particular emphasis on the content of Conjugated Linoleic Acid (CLA) and trans Fatty Acids (TFA), by using 100m high-polarity capillary column” “Evaluation of the oxidited fatty acids (OFA) content during the Parmigiano-Reggiano cheese seasoning” “Direct analysis of 4-desmethyl sterols and two dihydroxy triterpenes in saponified vegetal oils (olive oil and others) using liquid chromatography-mass spectrometry” “Quantitation of long chain poly-unsatured fatty acids (LC-PUFA) in base infant formulas by Gas Chromatography, and evaluation of the blending phases accuracy during their preparation” “Fatty acids composition of Parmigiano Reggiano cheese samples, with emphasis on trans isomers (TFA)”
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In den letzten fünf Jahren hat sich mit dem Begriff desspektralen Tripels eine Möglichkeit zur Beschreibungdes an Spinoren gekoppelten Gravitationsfeldes auf(euklidischen) nichtkommutativen Räumen etabliert. Die Dynamik dieses Gravitationsfeldes ist dabei durch diesogenannte spektrale Wirkung, dieSpur einer geeigneten Funktion des Dirac-Operators,bestimmt. Erstaunlicherweise kann man die vollständige Lagrange-Dichtedes (an das Gravitationsfeld gekoppelten) Standardmodellsder Elementarteilchenphysik, also insbesondere auch denmassegebenden Higgs-Sektor, als spektrale Wirkungeines entsprechenden spektralen Tripels ableiten. Diesesspektrale Tripel ist als Produkt des spektralenTripels der (kommutativen) Raumzeit mit einem speziellendiskreten spektralen Tripel gegeben. In der Arbeitwerden solche diskreten spektralen Tripel, die bis vorKurzem neben dem nichtkommutativen Torus die einzigen,bekannten nichtkommutativen Beispiele waren, klassifiziert. Damit kannnun auch untersucht werden, inwiefern sich dasStandardmodell durch diese Eigenschaft gegenüber anderenYang-Mills-Higgs-Theorien auszeichnet. Es zeigt sichallerdings, dasses - trotz mancher Einschränkung - eine sehr große Zahl vonModellen gibt, die mit Hilfe von spektralen Tripelnabgeleitet werden können. Es wäre aber auch denkbar, dass sich das spektrale Tripeldes Standardmodells durch zusätzliche Strukturen,zum Beispiel durch eine darauf ``isometrisch'' wirkendeHopf-Algebra, auszeichnet. In der Arbeit werden, um dieseFrage untersuchen zu können, sogenannte H-symmetrischespektrale Tripel, welche solche Hopf-Isometrien aufweisen,definiert.Dabei ergibt sich auch eine Möglichkeit, neue(H-symmetrische) spektrale Tripel mit Hilfe ihrerzusätzlichen Symmetrienzu konstruieren. Dieser Algorithmus wird an den Beispielender kommutativen Sphäre, deren Spin-Geometrie hier zumersten Mal vollständig in der globalen, algebraischen Sprache der NichtkommutativenGeometrie beschrieben wird, sowie dem nichtkommutativenTorus illustriert.Als Anwendung werden einige neue Beipiele konstruiert. Eswird gezeigt, dass sich für Yang-Mills Higgs-Theorien, diemit Hilfe von H-symmetrischen spektralen Tripeln abgeleitetwerden, aus den zusätzlichen Isometrien Einschränkungen andiefermionischen Massenmatrizen ergeben. Im letzten Abschnitt der Arbeit wird kurz auf dieQuantisierung der spektralen Wirkung für diskrete spektraleTripel eingegangen.Außerdem wird mit dem Begriff des spektralen Quadrupels einKonzept für die nichtkommutative Verallgemeinerungvon lorentzschen Spin-Mannigfaltigkeiten vorgestellt.
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Mit Hilfe von Molekulardynamik-Computersimulationen werdenin dieser Arbeit die Struktur und Dynamik von Gläsern undSchmelzen der Systeme 'NSx'=(Na2O)(xSiO2), mit x=2,3,5, und'AS2'=(Al2O3)(2SiO2) untersucht. Zur Beschreibung dermikroskopischen Wechselwirkungen dient ein Modellpotenzial,das auf einem effektiven Paarpotenzial aus der Literaturaufbaut. Simuliert wurden Teilchentrajektorien über mehrereNanosekunden im Bereich 6100 K >= T >= 2100 K sowie dieGlasstruktur bei 100 K (NSx) bzw. 300 K (AS2). Das Aufbrechen der tetraedrischen Netzwerkstruktur durch denNetzwerkmodifikator Na2O führt zur Ausbildung einerzusätzlichen Struktur auf intermediären Längenskalen, diebei allen Systemen NSx etwa dem Abstand übernächster Na-bzw. Si-Nachbarn eines Na-Atoms entspricht. Die diffusiveDynamik ist in allen Systeme NSx bis zu drei Größenordnungenschneller als in SiO2 . Sie nimmt mit wachsenderNa-Konzentration zu. Die Na-Diffusion zeigtArrhenius-Verhalten; hierbei vollführen die Na-Atome einaktiviertes Hüpfen durch eine erstarrte Si-O-Matrix. DieZustandsdichten werden bis ca. 20 THz durch dominanteNa-Moden bestimmt. Bei hohen Frequenzen weichen die für SiO2 typischen intratetraedrischen Si-O-Schwingungsmodenauf.Im Gegensatz zu Na2O wird Al2O3 in die tetraedrischeNetzwerkstruktur eingebunden. AS2 zeigt eine überwiegend ausAlO4- und SiO4-Tetraedern verknüpfte Polyederstruktur, beider sich die AlO4-Tetraeder lokal anders anordnen als dieSiO4-Tetraeder, um Ladungsausgleich zu gewährleisten. Esbilden sich typische 3(Si,Al)O4-Bausteine ('3-Cluster'). Sie führen auf intermediären Längenskalen zur Ausbildungeines Al-reichen perkolierenden Netzwerks, das dieSiO4-Struktur durchdringt. Im Vergleich zu SiO2 erhöht sichdie diffusive Dynamik aller Komponenten in AS2 um ca. zweiGrößenordnungen. Die intratetraedrischenAl-O-Steckschwingungsmoden sind wesentlich weicher als die typischen intratetraedrischen Si-O-Moden des SiO2.
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The aim of this study was to test the hypothesis that ear oximetry immediately after the release of a sustained Valsalva maneuver accurately detects patent foramen ovale (PFO). One hundred sixty-five scuba divers underwent transesophageal echocardiography (TEE; reference method) for PFO assessment. Ear oximetry of the right earlobe was performed in a different room within a time frame of 2 hours before or after TEE. The subject and the oximetry operator were unaware of the results of TEE. Oxygen saturation (SO(2)) measurements were obtained at baseline and during the release phase of 4 Valsalva maneuvers within 10 minutes, and the average SO(2) change (SO(2) at baseline minus SO(2) at Valsalva release) was determined as the primary study end point. One hundred seventeen divers had no PFO, and 48 (29%) had PFO by TEE (mean age 39 ± 8 years). The average SO(2) change was 0.79 ± 1.13% (i.e., a slight absolute SO(2) decrease in response to the Valsalva maneuver) in the group without PFO and 1.67 ± 1.19% in the PFO group (p <0.0001). Using receiver-operating characteristic curve analysis, a PFO as defined by TEE could be detected at a threshold of a Valsalva-induced decrease in SO(2) of ≥0.825 percentage points in comparison to baseline (sensitivity 0.756, specificity 0.706, area under the receiver-operating characteristic curve 0.763, p <0.0001, negative predictive value 0.882). In conclusion, the entirely noninvasive method of ear oximetry in response to repetitive Valsalva maneuvers is accurate and useful as a screening method for the detection of a PFO, as shown in this study of divers.
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PURPOSE To extend the capabilities of the Cone Location and Magnitude Index algorithm to include a combination of topographic information from the anterior and posterior corneal surfaces and corneal thickness measurements to further improve our ability to correctly identify keratoconus using this new index: ConeLocationMagnitudeIndex_X. DESIGN Retrospective case-control study. METHODS Three independent data sets were analyzed: 1 development and 2 validation. The AnteriorCornealPower index was calculated to stratify the keratoconus data from mild to severe. The ConeLocationMagnitudeIndex algorithm was applied to all tomography data collected using a dual Scheimpflug-Placido-based tomographer. The ConeLocationMagnitudeIndex_X formula, resulting from analysis of the Development set, was used to determine the logistic regression model that best separates keratoconus from normal and was applied to all data sets to calculate PercentProbabilityKeratoconus_X. The sensitivity/specificity of PercentProbabilityKeratoconus_X was compared with the original PercentProbabilityKeratoconus, which only uses anterior axial data. RESULTS The AnteriorCornealPower severity distribution for the combined data sets are 136 mild, 12 moderate, and 7 severe. The logistic regression model generated for ConeLocationMagnitudeIndex_X produces complete separation for the Development set. Validation Set 1 has 1 false-negative and Validation Set 2 has 1 false-positive. The overall sensitivity/specificity results for the logistic model produced using the ConeLocationMagnitudeIndex_X algorithm are 99.4% and 99.6%, respectively. The overall sensitivity/specificity results for using the original ConeLocationMagnitudeIndex algorithm are 89.2% and 98.8%, respectively. CONCLUSIONS ConeLocationMagnitudeIndex_X provides a robust index that can detect the presence or absence of a keratoconic pattern in corneal tomography maps with improved sensitivity/specificity from the original anterior surface-only ConeLocationMagnitudeIndex algorithm.
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This study aims at assessing the skill of several climate field reconstruction techniques (CFR) to reconstruct past precipitation over continental Europe and the Mediterranean at seasonal time scales over the last two millennia from proxy records. A number of pseudoproxy experiments are performed within the virtual reality ofa regional paleoclimate simulation at 45 km resolution to analyse different aspects of reconstruction skill. Canonical Correlation Analysis (CCA), two versions of an Analog Method (AM) and Bayesian hierarchical modeling (BHM) are applied to reconstruct precipitation from a synthetic network of pseudoproxies that are contaminated with various types of noise. The skill of the derived reconstructions is assessed through comparison with precipitation simulated by the regional climate model. Unlike BHM, CCA systematically underestimates the variance. The AM can be adjusted to overcome this shortcoming, presenting an intermediate behaviour between the two aforementioned techniques. However, a trade-off between reconstruction-target correlations and reconstructed variance is the drawback of all CFR techniques. CCA (BHM) presents the largest (lowest) skill in preserving the temporal evolution, whereas the AM can be tuned to reproduce better correlation at the expense of losing variance. While BHM has been shown to perform well for temperatures, it relies heavily on prescribed spatial correlation lengths. While this assumption is valid for temperature, it is hardly warranted for precipitation. In general, none of the methods outperforms the other. All experiments agree that a dense and regularly distributed proxy network is required to reconstruct precipitation accurately, reflecting its high spatial and temporal variability. This is especially true in summer, when a specifically short de-correlation distance from the proxy location is caused by localised summertime convective precipitation events.
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En las últimas décadas, el mundo del trabajo se ha modificado drásticamente. Considerando que dichos cambios no sólo modificaron las estrategias materiales de vida de los trabajadores, sino también sus valoraciones y percepciones con respecto al trabajo y a sí mismos, en este estudio pretendemos indagar sobre la forma en que los sujetos enfrentaron tales fenómenos y las consecuencias que los mismos produjeron en sus subjetividades. Presentamos aquí un estudio de caso que se propone describir y analizar las trayectorias laborales, a lo largo de los últimos quince años, de los ex trabajadores de la empresa O.F.A., una mediana fábrica metalúrgica del Gran La Plata que cerró por quiebra en el año 1993. Dados los objetivos de investigación, hemos adoptado una perspectiva metodológica cualitativa utilizando el concepto de trayectoria laboral, que intenta poner de manifiesto la relación dinámica que se establece entre las condiciones estructurales y las estrategias que ponen en juego los sujetos. En primer lugar, planteamos la descripción de las trayectorias laborales analizadas, dando cuenta del trabajo en la empresa, las búsquedas laborales emprendidas y las inserciones laborales actuales. En segundo lugar, nos centramos en el análisis de las valoraciones y percepciones que tienen los trabajadores con respecto al trabajo pasado, al actual y a las transformaciones ocurridas a lo largo de sus trayectorias. Finalmente señalamos los principales resultados, concluyendo que a pesar de producirse el quiebre de las trayectorias, el trabajo sigue siendo un eje identitario estructurante en la vida de los trabajadores estudiados
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En las últimas décadas, el mundo del trabajo se ha modificado drásticamente. Considerando que dichos cambios no sólo modificaron las estrategias materiales de vida de los trabajadores, sino también sus valoraciones y percepciones con respecto al trabajo y a sí mismos, en este estudio pretendemos indagar sobre la forma en que los sujetos enfrentaron tales fenómenos y las consecuencias que los mismos produjeron en sus subjetividades. Presentamos aquí un estudio de caso que se propone describir y analizar las trayectorias laborales, a lo largo de los últimos quince años, de los ex trabajadores de la empresa O.F.A., una mediana fábrica metalúrgica del Gran La Plata que cerró por quiebra en el año 1993. Dados los objetivos de investigación, hemos adoptado una perspectiva metodológica cualitativa utilizando el concepto de trayectoria laboral, que intenta poner de manifiesto la relación dinámica que se establece entre las condiciones estructurales y las estrategias que ponen en juego los sujetos. En primer lugar, planteamos la descripción de las trayectorias laborales analizadas, dando cuenta del trabajo en la empresa, las búsquedas laborales emprendidas y las inserciones laborales actuales. En segundo lugar, nos centramos en el análisis de las valoraciones y percepciones que tienen los trabajadores con respecto al trabajo pasado, al actual y a las transformaciones ocurridas a lo largo de sus trayectorias. Finalmente señalamos los principales resultados, concluyendo que a pesar de producirse el quiebre de las trayectorias, el trabajo sigue siendo un eje identitario estructurante en la vida de los trabajadores estudiados
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En las últimas décadas, el mundo del trabajo se ha modificado drásticamente. Considerando que dichos cambios no sólo modificaron las estrategias materiales de vida de los trabajadores, sino también sus valoraciones y percepciones con respecto al trabajo y a sí mismos, en este estudio pretendemos indagar sobre la forma en que los sujetos enfrentaron tales fenómenos y las consecuencias que los mismos produjeron en sus subjetividades. Presentamos aquí un estudio de caso que se propone describir y analizar las trayectorias laborales, a lo largo de los últimos quince años, de los ex trabajadores de la empresa O.F.A., una mediana fábrica metalúrgica del Gran La Plata que cerró por quiebra en el año 1993. Dados los objetivos de investigación, hemos adoptado una perspectiva metodológica cualitativa utilizando el concepto de trayectoria laboral, que intenta poner de manifiesto la relación dinámica que se establece entre las condiciones estructurales y las estrategias que ponen en juego los sujetos. En primer lugar, planteamos la descripción de las trayectorias laborales analizadas, dando cuenta del trabajo en la empresa, las búsquedas laborales emprendidas y las inserciones laborales actuales. En segundo lugar, nos centramos en el análisis de las valoraciones y percepciones que tienen los trabajadores con respecto al trabajo pasado, al actual y a las transformaciones ocurridas a lo largo de sus trayectorias. Finalmente señalamos los principales resultados, concluyendo que a pesar de producirse el quiebre de las trayectorias, el trabajo sigue siendo un eje identitario estructurante en la vida de los trabajadores estudiados
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The ability to reproduce reduced gravity conditions for long periods is one of the reasons why the orbiting laboratory is so attractive. In this paper several fluid dynamics problem areas are reviewed in which zero-gravity conditions are of great importance. Although emphasis is placed on space processing, there are some older problems also in which gravity masks the phenomcna, impeding a reasonably simple approach to the solution. Three problems are considered: Thermal convection under reduced gravity. The dumping effect ofsurface gravity waves at the outset of convection induced by surface tractions is discussed in particular. The existence of convection is of concern for some satellite thermal control techniques presently used, and for most of the proposed manufacturing processes. Whereas convection should be normally avoided, problems related to the containerless stirring ofa melt constitute an exception. Secondly, gravity and chemical reactions. Although chemical reactions are independent of gravity because of the small mass of the molecules and atoms involved, in many cases the reaction rate dcpends on the arrival of the species to the reaction zone. When the arrival process is buoyancy-controlled, the net specd of the reaction will be affected by the gravity. Thirdly, two-phase flows under reduced gravity provkle interesting problems from boiling heat transfer to degasslng of melts. This part of the paper deals only with the measurement of sound veiocity in a liquid containing bubbles. It is suggested that such measurements should be mude under reduced gravity to provide reliable residís.