845 resultados para Developmental job experiences of fit and pressure
Resumo:
This paper investigates the determinants of job satisfaction of university graduates in Spain. We base our analysis on Locke"s discrepancy theory [Locke (1969)] and decompose subjective evaluation of job characteristics into surplus and deficit levels. We also study the importance of overeducation and over-skilling on job satisfaction. We use REFLEX data, a survey of university graduates. We conclude that job satisfaction is mostly determined by the subjective evaluation of intrinsic job characteristics, with an asymmetric impact of surpluses and deficits. Over-skilling is much more important than over-education in explaining the job satisfaction of university graduates, although the latter is also significant.
Resumo:
This is the first TEM examination of vitellogenesis in the cestode Aporhynchus menezesi, a parasite of the velvet belly lanternshark Etmopterus spinax and a member of a little-studied trypanorhynch family, the Aporhynchidae. The synthetic activity of vitellocytes plays two important functions in the developmental biology of cestodes: (1) their shell-globules serve in eggshell formation; and (2) their accumulated reserves of glycogen and lipids represent a food source for the developing embryo. In A. menezesi, vitelline follicles consist of cells at various stages of development, from peripheral, immature cells of the gonial type to mature cells towards the centre of the follicle. These stages are: (I) immature; (II) early differentiation; (III) advanced maturation; and (IV) mature. Gradual changes involved in this process occur within each stage. Vitellogenesis involves: (1) an increase in cell volume; (2) the development of a smooth endoplasmic reticulum and an accelerated formation and accumulation of both unsaturated and saturated lipid droplets, along with their continuous enlargement and fusion; (3) the formation of individual β-glycogen particles and their accumulation in the form of glycogen islands scattered among lipid droplets in the cytoplasm of maturing and mature vitellocytes; (4) the rapid accumulation of large, moderately saturated lipid droplets accompanied by dense accumulations of β-glycogen along with proteinaceous shell-globules or shell-globule clusters in the peripheral layer during the advanced stage of maturation; (5) the development of cisternae of granular endoplasmic reticulum that produce dense, proteinaceous shell-globules; (6) the development of Golgi complexes engaged in the packaging of this material; and (7) the progressive and continuous enlargement of shell-globules into very large clusters in the peripheral layer during the advanced stage of maturation. Vitellogenesis in A. menezesi, only to some extent, resembles that previously described for four other trypanorhynchs. It differs in: (i) the reversed order of secretory activities in the differentiating vitellocytes, namely the accumulation of large lipid droplets accompanied by glycogenesis or β-glycogen formation during early differentiation (stage II), i.e. before the secretory activity, which is predominantly protein synthesis for shell-globule formation (stage III); (ii) the very heavy accumulation of large lipid droplets during the final stage of cytodifferentiation (stage IV); and (iii) the small number of β-glycogen particles present in mature vitellocytes. Ultracytochemical staining with PA-TCH-SP for glycogen proved positive for a small number of β-glycogen particles in differentiating and mature vitellocytes. Hypotheses, concerning the interrelationships of patterns of vitellogenesis, possible modes of egg formation, embryonic development and life-cycles, are commented upon.
Resumo:
In the past four decades, women have made major inroads into occupations previously dominated by men. This paper examines whether occupational feminization is accompanied by a decline in wages: Do workers suffer a wage penalty if they remain in, or move into, feminizing occupations? We analyze this question over the 1990s and 2000s in Britain, Germany, and Switzerland, using longitudinal panel data to estimate individual fixed effects for men and women. Moving from an entirely male to an entirely female occupation entails a loss in individual earnings of 13 percent in Britain, 7 percent in Switzerland, and 3 percent in Germany. The impact of occupational feminization on wages is not linear, but sets apart occupations holding more than 60 percent of women. Moving into such female occupations incurs a wage penalty. Contrary to the prevailing idea in economics, differences in productivity-human capital, job-specific skills, and time investment-do not fully explain the wage gap between male and female occupations. The wage penalty associated with working in a female occupation is also much larger where employer discretion is greater-in the private sector-than where wagesetting is guided by formal rules-the public sector. These findings suggest that wage disparities across male and female occupations are due to gender devaluation.
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To-date, there has been no effective chiral capillary electrophoresis-mass spectrometry (CE-MS) method reported for the simultaneous enantioseparation of the antidepressant drug, venlafaxine (VX) and its structurally-similar major metabolite, O-desmethylvenlafaxine (O-DVX). This is mainly due to the difficulty of identifying MS compatible chiral selector, which could provide both high enantioselectivity and sensitive MS detection. In this work, poly-sodium N-undecenoyl-L,L-leucylalaninate (poly-L,L-SULA) was employed as a chiral selector after screening several dipeptide polymeric chiral surfactants. Baseline separation of both O-DVX and VX enantiomers was achieved in 15min after optimizing the buffer pH, poly-L,L-SULA concentration, nebulizer pressure and separation voltage. Calibration curves in spiked plasma (recoveries higher than 80%) were linear over the concentration range 150-5000ng/mL for both VX and O-DVX. The limit of detection (LOD) was found to be as low as 30ng/mL and 21ng/mL for O-DVX and VX, respectively. This method was successfully applied to measure the plasma concentrations of human volunteers receiving VX or O-DVX orally when co-administered without and with indinivar therapy. The results suggest that micellar electrokinetic chromatography electrospray ionization-tandem mass spectrometry (MEKC-ESI-MS/MS) is an effective low cost alternative technique for the pharmacokinetics and pharmacodynamics studies of both O-DVX and VX enantiomers. The technique has potential to identify drug-drug interaction involving VX and O-DVX enantiomers while administering indinivar therapy.
Resumo:
This is the first TEM examination of vitellogenesis in the cestode Aporhynchus menezesi, a parasite of the velvet belly lanternshark Etmopterus spinax and a member of a little-studied trypanorhynch family, the Aporhynchidae. The synthetic activity of vitellocytes plays two important functions in the developmental biology of cestodes: (1) their shell-globules serve in eggshell formation; and (2) their accumulated reserves of glycogen and lipids represent a food source for the developing embryo. In A. menezesi, vitelline follicles consist of cells at various stages of development, from peripheral, immature cells of the gonial type to mature cells towards the centre of the follicle. These stages are: (I) immature; (II) early differentiation; (III) advanced maturation; and (IV) mature. Gradual changes involved in this process occur within each stage. Vitellogenesis involves: (1) an increase in cell volume; (2) the development of a smooth endoplasmic reticulum and an accelerated formation and accumulation of both unsaturated and saturated lipid droplets, along with their continuous enlargement and fusion; (3) the formation of individual β-glycogen particles and their accumulation in the form of glycogen islands scattered among lipid droplets in the cytoplasm of maturing and mature vitellocytes; (4) the rapid accumulation of large, moderately saturated lipid droplets accompanied by dense accumulations of β-glycogen along with proteinaceous shell-globules or shell-globule clusters in the peripheral layer during the advanced stage of maturation; (5) the development of cisternae of granular endoplasmic reticulum that produce dense, proteinaceous shell-globules; (6) the development of Golgi complexes engaged in the packaging of this material; and (7) the progressive and continuous enlargement of shell-globules into very large clusters in the peripheral layer during the advanced stage of maturation. Vitellogenesis in A. menezesi, only to some extent, resembles that previously described for four other trypanorhynchs. It differs in: (i) the reversed order of secretory activities in the differentiating vitellocytes, namely the accumulation of large lipid droplets accompanied by glycogenesis or β-glycogen formation during early differentiation (stage II), i.e. before the secretory activity, which is predominantly protein synthesis for shell-globule formation (stage III); (ii) the very heavy accumulation of large lipid droplets during the final stage of cytodifferentiation (stage IV); and (iii) the small number of β-glycogen particles present in mature vitellocytes. Ultracytochemical staining with PA-TCH-SP for glycogen proved positive for a small number of β-glycogen particles in differentiating and mature vitellocytes. Hypotheses, concerning the interrelationships of patterns of vitellogenesis, possible modes of egg formation, embryonic development and life-cycles, are commented upon.
Resumo:
In this research we are examining what is the status of logistics and operations management in Finnish and Swedish companies. Empirical data is based on the web based questionnaire, which was completed in the end of 2007 and early 2008. Our examination consists of roughly 30 answers from largest manufacturing (highest representation in our sample), trade and logistics/distribution companies. Generally it could be argued that these companies operate in complex environment, where number of products, raw materials/components and suppliers is high. However, usually companies rely on small amount of suppliers per raw material/component (highest frequency is 2), and this was especially the case among Swedish companies, and among those companies, which favoured overseas sourcing. Sample consisted of companies which mostly are operating in an international environment, and are quite often multinationals. Our survey findings reveal that companies in general have taken logistics and information technology as part of their strategy process; utilization of performance measures as well as system implementations have followed the strategy decisions. In the transportation mode side we identify that road transports dominate all transport flow classes (inbound, internal and outbound), followed by sea and air. Surprisingly small amount of companies use railways, but in general we could argue that Swedish companies prefer this mode over Finnish counterparts. With respect of operations outsourcing, we found that more traditional areas of logistics outsourcing are driving factors in company's performance measurement priority. In contrary to previous research, our results indicate that the scope of outsourcing is not that wide in logistics/operations management area, and companies are not planning to outsource more in the near future. Some support is found for more international operations and increased outsourcing activity. From the increased time pressure of companies, we find evidence that local as well as overseas customers expect deliveries within days or weeks, but suppliers usually supply within weeks or months. So, basically this leads into considerable inventory holding. Interestingly local and overseas sourcing strategy does not have that great influence on lead time performance of these particular sourcing areas - local strategy is anyway considerably better in responding on market changes due to shorter supply lead times. In the end of our research work we have completed correlation analysis concerning items asked with Likert scale. Our analysis shows that seeing logistics more like a process rather than function, applying time based management, favouring partnerships and measuring logistics within different performance dimensions results on preferred features and performance found in logistics literature.
Resumo:
The connection between road traffic safety and criminal behavior has recently become a topic of interest in the literature, although little emphasis placed on the relationship with road accidents. Evidence worldwide shows that people who commit other offences characteristic of antisocial attitudes, are more prone to suffer road traffic accidents and infringe traffic laws. Here we examine the records of the 28 current member states of the European Union over the period 1999 - 2010. Our aim is to test the hypothesis that crime rates (and specifically, motor vehicle-related crimes) may be considered as predictors of fatal road traffic accidents. If they may, this could justify, at least prima facie, the tendency in several countries to consider traffic offences as crimes in their penal codes and to toughen the punishment imposed on those who commit them. We also analyze the effect of the severity of the legal system applied to traffic offences. Our results reveal that road traffic fatality rates are higher in countries whose inhabitants have more aggressive behavior, while the rates are lower in countries with more severe penal systems.
Resumo:
The connection between road traffic safety and criminal behavior has recently become a topic of interest in the literature, although little emphasis placed on the relationship with road accidents. Evidence worldwide shows that people who commit other offences characteristic of antisocial attitudes, are more prone to suffer road traffic accidents and infringe traffic laws. Here we examine the records of the 28 current member states of the European Union over the period 1999 - 2010. Our aim is to test the hypothesis that crime rates (and specifically, motor vehicle-related crimes) may be considered as predictors of fatal road traffic accidents. If they may, this could justify, at least prima facie, the tendency in several countries to consider traffic offences as crimes in their penal codes and to toughen the punishment imposed on those who commit them. We also analyze the effect of the severity of the legal system applied to traffic offences. Our results reveal that road traffic fatality rates are higher in countries whose inhabitants have more aggressive behavior, while the rates are lower in countries with more severe penal systems.
Resumo:
Ultrafiltration (UF) is widely applied in different separation processes in the pulp and paper industry. The growing need to protect the environment, a lack of pure water and an interest in producing high-value chemicals from compounds present in process waters will probably lead to an increase in the use of UF in the pulp and paper industry. The efficiency and cost-effectiveness of a UF process depends on the applied membrane. The membrane should have a high and stable filtration capacity, a particular selectivity and a long operational lifetime. To meet these requirements a membrane should have a low fouling tendency. In addition, it should withstand the prevailing operational and chemical conditions. This thesis evaluates the performance and applicability of the regenerated cellulose (RC) membranes 00030T and C2 in the treatment of pulp and paper mill process waters based on the requirements above. The results demonstrated that both the tested RC membranes fulfilled well the requirement of high filtration capacity. In addition, in the filtration of a paper mill clear filtrate (CF) the RC membranes were not as greatly affected by variations in the CF quality as a polysulphone membrane. Furthermore, due to their extreme hydrophilicity and weak charge the fouling tendency of the membranes can be expected to be low in pulp and paper mill filtration applications. It is, however, known that fouling cannot be totally avoided even when the membrane is chosen very carefully. This study indicated that carbohydrates influenced negatively on permeability and caused fouling in the filtration of groundwood mill circulation water. Thus, a pre-treatment effectively reducing the amount of carbohydrates might help to maintain a stable capacity. However, the results of the thesis also showed that the removal of some of the possible foulants might just increase the harmful effect of others. Multivariate examination was useful in the understanding of the complicated factors causing the unstable capacity. The thesis also revealed that the 00030T and C2 membranes can be used at high pressure (max. tested pressure 12 bar). The C2 membrane, having a sponge-like substructure, was more pressure resistant, and its performance was more stable at high pressure compared to the UCO30T membrane containing macrovoids in its substructure. Both tested membranes can, according to the results, also be used at temperatures as high as 70°C in acidic, neutral and alkaline conditions. However, the use at extreme conditions might cause faster ageing of the membranes compared to ageing in neutral conditions. The thesis proved that both the tested RC membranes are very suitable for pulp and paper mill applications and that the membranes can be utilised in processes operating in challenging conditions. Thus, they could be used in more demanding applications than supposed earlier.
Resumo:
This paper focuses on the study of the factorial structure of an inventory to estimate the subjective perception of insecurity and fear of crime. Made from the review of the literature on the subject and the results obtained in previous works, this factor structure shows that this attitude towards insecurity and fear of crime is identified through a number of latent factors which are schematically summarized in (a) personal safety, (b) the perception of personal and social control, (c) the presence of threatening people or situations, (d) the processes of identity and space appropriation, (e) satisfaction with the environment, and (f) the environmental and the use of space. Such factors are relevant dimensions to analyze the phenomenon. Method: A sample of 571 participants in a neighborhood of Barcelona was evaluated with the proposed inventory, which yielded data from the distributions of all the items provided. The administration was conducted by researchers specially trained for it and the results were analyzed by using standard procedures in the confirmatory factor analysis (CFA) from the hypothesized theoretical structure. The analysis was performed by decatypes according to the different response scales prepared in the inventory and their ordinal nature, and by estimating the polychoric correlation coefficients. The results show an acceptable fit of the proposed model, an appropriate behavior of the residuals and statistically significant estimates of the factor loadings. This would indicate the goodness of the proposed factor structure.
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Successful generation of high producing cell lines requires the generation of cell clones expressing the recombinant protein at high levels and the characterization of the clones' ability to maintain stable expression levels. The use of cis-acting epigenetic regulatory elements that improve this otherwise long and uncertain process has revolutionized recombinant protein production. Here we review and discuss new insights into the molecular mode of action of the matrix attachment regions (MARs) and ubiquitously-acting chromatin opening elements (UCOEs), i.e. cis-acting elements, and how these elements are being used to improve recombinant protein production. These elements can help maintain the chromatin environment of the transgene genomic integration locus in a transcriptionally favorable state, which increases the numbers of positive clones and the transgene expression levels. Moreover, the high producing clones tend to be more stable in long-term cultures even in the absence of selection pressure. Therefore, by increasing the probability of isolating a high producing clone, as well as by increasing transcription efficiency and stability, these elements can significantly reduce the time and cost required for producing large quantities of recombinant proteins.
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The profound crisis that has affected the Spanish economy since mid - 2008 has been characterized by significant job losses and a marked rise in the country´s unemployment rate. However, unemployment has had a differential impact on different population groups. Compared to native, immigrant workers have experienced higher rates of job loss. Against this backdrop, this paper examines the differences between immigrants and natives (distinguished by gender) in terms of their probability of suffering job loss in the downturn of late 2008 and 2009. Our results indicate that the higher rate of job loss among female immigrant workers can be fully explained by their lower endowment of human capital. By contrast, human capital endowment and over-representation in certain occupations, sectors and regions in which the crisis had greatest impact do not appear to be the only reason for the penalty suffered by immigrant males in terms of their chances of losing their job in the downturn.
Resumo:
Neuropeptide Y (NPY) is an abundant neurotransmitter in the brain and sympathetic nervous system (SNS). Hypothalamic NPY is known to be a key player in food intake and energy expenditure. NPY’s role in cardiovascular regulation has also been shown. In humans, a Leucine 7 to Proline 7 single nucleotide polymorphism (p.L7P) in the signal peptide of the NPY gene has been associated with traits of metabolic syndrome. The p.L7P subjects also show increased stress-related release of NPY, which suggests that more NPY is produced and released from SNS. The main objective of this study was to create a novel mouse model with noradrenergic cell-targeted overexpression of NPY, and to characterize the metabolic and vascular phenotype of this model. The mouse model was named OE-NPYDBH mouse. Overexpression of NPY in SNS and brain noradrenergic neurons led to increased adiposity without significant weight gain or increased food intake. The mice showed lipid accumulation in the liver at young age, which together with adiposity led to impaired glucose tolerance and hyperinsulinemia with age. The mice displayed stress-related increased mean arterial blood pressure, increased plasma levels of catecholamines and enhanced SNS activity measured by GDP binding activity to brown adipose tissue mitochondria. Sexual dimorphism in NPY secretion pattern in response to stress was also seen. In an experimental model of vascular injury, the OE-NPYDBH mice developed more pronounced neointima formation compared with wildtype controls. These results together with the clinical data indicate that NPY in noradrenergic cells plays an important role in the pathogenesis of metabolic syndrome and related diseases. Furthermore, new insights on the role of the extrahypothalamic NPY in the process have been obtained. The OE-NPYDBH model provides an important tool for further stress and metabolic syndrome-related studies.
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The purpose of this comparative study is to profile second language learners by exploring the factors which have an impact on their learning. The subjects come from two different countries: one group comes from Milwaukee, US, and the other from Turku, Finland. The subjects have attended bilingual classes from elementary school to senior high school in their respective countries. In the United States, the subjects (N = 57) started in one elementary school from where they moved on to two high schools in the district. The Finnish subjects (N = 39) attended the same school from elementary to high school. The longitudinal study was conducted during 1994-2004 and combines both qualitative and quantitative research methods. A Pilot Study carried out in 1990-1991 preceded the two subsequent studies that form the core material of this research. The theoretical part of the study focuses first on language policies in the United States and Finland: special emphasis is given to the history, development and current state of bilingual education, and the factors that have affected policy-making in the provision of language instruction. Current language learning theories and models form the theoretical foundation of the research, and underpin the empirical studies. Cognitively-labeled theories are at the forefront, but sociocultural theory and the ecological approach are also accounted for. The research methods consist of questionnaires, compositions and interviews. A combination of statistical methods as well as content analysis were used in the analysis. The attitude of the bilingual learners toward L1 and L2 was generally positive: the subjects enjoyed learning through two languages and were motivated to learn both. The knowledge of L1 and parental support, along with early literacy in L1, facilitated the learning of L2. This was particularly evident in the American subject group. The American subjects’ L2 learning was affected by the attitudes of the learners to the L1 culture and its speakers. Furthermore, the negative attitudes taken by L1 speakers toward L2 speakers and the lack of opportunities to engage in activities in the L1 culture affected the American subjects’ learning of L2, English. The research showed that many American L2 learners were isolated from the L1 culture and were even afraid to use English in everyday communication situations. In light of the research results, a politically neutral linguistic environment, which the Finnish subjects inhabited, was seen to be more favorable for learning. The Finnish subjects were learning L2, English, in a neutral zone where their own attitudes and motivation dictated their learning. The role of L2 as a means of international communication in Finland, as opposed to a means of exercising linguistic power, provided a neutral atmosphere for learning English. In both the American and Finnish groups, the learning of other languages was facilitated when the learner had a good foundation in their L1, and the learning of L1 and L2 were in balance. Learning was also fostered when the learners drew positive experiences from their surroundings and were provided with opportunities to engage in activities where L2 was used.
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Fuzzy subsets and fuzzy subgroups are basic concepts in fuzzy mathematics. We shall concentrate on fuzzy subgroups dealing with some of their algebraic, topological and complex analytical properties. Explorations are theoretical belonging to pure mathematics. One of our ideas is to show how widely fuzzy subgroups can be used in mathematics, which brings out the wealth of this concept. In complex analysis we focus on Möbius transformations, combining them with fuzzy subgroups in the algebraic and topological sense. We also survey MV spaces with or without a link to fuzzy subgroups. Spectral space is known in MV algebra. We are interested in its topological properties in MV-semilinear space. Later on, we shall study MV algebras in connection with Riemann surfaces. In fact, the Riemann surface as a concept belongs to complex analysis. On the other hand, Möbius transformations form a part of the theory of Riemann surfaces. In general, this work gives a good understanding how it is possible to fit together different fields of mathematics.