RESUMO
The oxidative stability of biodiesel is defined by its relative resistance to the action of oxygen at room temperature. Its determination is an essential reference to the quality of biofuel and a significant parameter to be determined. This parameter concerns the quality of the biodiesel to be supplied to the consumer, and its determination is fundamental to maintaining the engine's proper functioning. Raman spectroscopy allows the rapid obtaining of structural information regarding biodiesel quality and, when aided by multivariate analysis methods, allows a quantitative determination of specific properties. This work uses Raman spectroscopy, Multivariate Curve Resolution with Alternative Least Squares (MCR-ALS) method, and Evolving Factor Analysis (EFA) to study biodiesel's oxidation kinetics. Also, the vibrational modes C = C, CH2, and CH3 were identified as the main structural groups involved in this process, corroborating previous studies. The MCR-ALS & EFA combination allowed modeling of the degradation kinetics following an A â B â C mechanism, where A corresponds to the biodiesel (starting material), B is related to the hydroperoxide mixture, and C is the final product. The results also suggested that this process follows a first-order reaction, with kinetic constant values of k1 = 0.0056 min-1 and k2 = 0.0031 min-1.
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BACKGROUND: One of the most significant human qualities is the ability to develop, implement, and flexibly maintain planned behaviour in order to achieve one's goals. Self-regulation has become a relatively well-researched area in the field of psychology and pedagogy. However, empirically valid and reliable instrument is still missing across European context. The primary goal of this research was to analyze the psychometric properties of the Czech version of the Self-Regulation Questionnaire (SRQ-CZ) among adult learners from Poland, Serbia, Slovakia, and the Czech Republic. OBJECTIVE: The aim of the present study was to examine the factor structure and psychometric properties of the SRQ-CZ validated in the Czech educational context in a multi-cultural sample. METHODS: A total of 1711 adult learners from European countries including Poland, Serbia, Slovakia, and the Czech Republic completed the SRQ-CZ. The first step to reviewing the validity of the SRQ-CZ included testing face validity. Furthermore, exploratory factor analysis (EFA) was performed on half the sample and confirmatory factor analysis (CFA) on the other half. Measurement invariance was conducted across gender, age, and country followed by the evaluation of the reliability of the final instrument. RESULTS: EFA showed that a three-factor structure best fit the data. The originally proposed Impulse Control and Self-Direction are merged into one distinct factor, while Decision Making and Goal Orientation comprise the other two. Goodness-of-fit statistics yielded from CFA showed a good fit for the model, introducing a reliable and measurement invariant instrument. CONCLUSION: The present study used a diverse multi-cultural sample to explore the factorial structure and psychometric properties of the SRQ-CZ. A three-factor model was obtained as the result of the exploratory and confirmatory factor analyses. Further analysis aiming at measurement invariance, comparing the sample according to gender, age, and country, led to satisfactory results. The only exception was a lack of model fit in the case of Serbia. Although further psychometric evaluation of the SRQ-CZ is still needed, the presented results constitute significant findings, confirming instrument validity and utility as a measure of generalized self-regulation capacity across adult learners in European educational context.
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Common Agricultural Policy (CAP) reform in the European Union introduced a new element: greening. The aim of greening is to support the environment and create non-productive value in agriculture. The main element of greening is the Ecological Focus Area (EFA) meaning that a portion of farmland area has to be designed for environmental purposes. This article consists of an evaluatation of greening and its elements in the first year CAP reform has come into force. Surveys were used as a tool to gather information about farm characteristics, ways to meet greening requirements as well as the opinions of farmers as to changes in direct subsidies and greening obligations. The research was conducted in 2015 directly interviewing 290 farmers from the whole of Poland. The farmers interviewed lived in different parts of the country and had different size farms. Data was prepared with the use of spreadsheets and were analysed using the R statistical program and the gmodel and vcd statistical packages were used during the calculations. Polish farmers are against greening. Greening does not significantly change the way farmers run their farms. They choose the cheapest options of EFA which are usually not the best for the environment. Furthermore, farmers have to bear the cost of introducing the new elements themselves. Despite a high number of environmental and agricultural advantages offered by new farming methods, crop rotation and after-crop sowing duty, CAP reform is assessed in a negative light. As a result of negative opinions held by farmers due to the lack of subsidies, farmers may not continue greening practices in the future.
Assuntos
Humanos , Agricultura Sustentável/economia , Desenvolvimento Ecológico , Gestão e Planejamento de Terrenos/políticas , Polônia , População Rural/estatística & dados numéricos , Fazendeiros/estatística & dados numéricos , Gestão dos Recursos NaturaisRESUMO
Common Agricultural Policy (CAP) reform in the European Union introduced a new element: greening. The aim of greening is to support the environment and create non-productive value in agriculture. The main element of greening is the Ecological Focus Area (EFA) meaning that a portion of farmland area has to be designed for environmental purposes. This article consists of an evaluatation of greening and its elements in the first year CAP reform has come into force. Surveys were used as a tool to gather information about farm characteristics, ways to meet greening requirements as well as the opinions of farmers as to changes in direct subsidies and greening obligations. The research was conducted in 2015 directly interviewing 290 farmers from the whole of Poland. The farmers interviewed lived in different parts of the country and had different size farms. Data was prepared with the use of spreadsheets and were analysed using the R statistical program and the gmodel and vcd statistical packages were used during the calculations. Polish farmers are against greening. Greening does not significantly change the way farmers run their farms. They choose the cheapest options of EFA which are usually not the best for the environment. Furthermore, farmers have to bear the cost of introducing the new elements themselves. Despite a high number of environmental and agricultural advantages offered by new farming methods, crop rotation and after-crop sowing duty, CAP reform is assessed in a negative light. As a result of negative opinions held by farmers due to the lack of subsidies, farmers may not continue greening practices in the future.(AU)
Assuntos
Humanos , Agricultura Sustentável/economia , Desenvolvimento Ecológico , Gestão e Planejamento de Terrenos/políticas , População Rural/estatística & dados numéricos , Polônia , Gestão dos Recursos Naturais , /tendências , Fazendeiros/estatística & dados numéricosRESUMO
Tem sido dada uma importância muito maior à participação dos trabalhadores e retenção desde que a Índia está enfrentando a maior taxa de atrito globalmente Economic Times, 2015¹. Assim, considerando os fatores de Pessoa - job apto a interpretar o impacto no compromisso de trabalho é muito bem essencial, especialmente no Compromisso scenario.Work atual é um elemento vital de qualquer constituição que tem um impacto notável na produtividade e funcionamento . Mas, quando os funcionários vão sentir o compromisso de trabalho é o futuro pergunta. Existe uma forte relação entre ajuste pessoa - trabalho e compromisso de trabalho . ajuste pessoa - trabalho é a compatibilidade entre competência e habilidades da pessoa e as exigências do trabalho Zheng et al.². Se existe uma incompatibilidade entre o ajuste pessoa - trabalho, então as consequências podem resultar em compromisso de trabalho pobre, baixa satisfação no trabalho e extremamente menor envolvimento no trabalho. OBJETIVO: Este estudo analisou os principais fatores que contribuem para a pessoa- a compatibilidade de trabalho entre TI trabalhadores e também analisou a relação e o impacto da compatibilidade de trabalho Person- no compromisso de trabalho. MÉTODO: Exploratory Factor de Analysis (EFA) foi usado para filtrar os fatores-chave inicialmente, seguido por uma técnica de regressão linear para determinar o impacto da pessoa- fatores de compatibilidade emprego no compromisso de trabalho em uma amostra de 300 empregados. EFA utilizada análise de componentes principais para a extração e Promax para rotação . Finalmente a análise de regressão foi realizada para prever o compromisso de trabalho por meio de variáveis estatisticamente significativas de compatibilidade pessoa - trabalho. RESULTADOS: Os resultados revelaram os principais fatores que determinam o nível de compromisso de trabalho são condições de RH, remuneração e benefícios e relacionamento entre os colegas de trabalho. CONCLUSÃO: Os principais fatores que são responsáveis pela criação de compromisso de trabalho entre empregados são Relacionamento, Políticas e estratégias de RH, remuneração e benefícios, o trabalho autonomia e crescimento do empregado. Os regride mais contribuem que representa a criação de compromisso de trabalho são as políticas de RH, remuneração e benefícios, o crescimento do empregado e trabalhar autonomia. O impacto da compatibilidade pessoa-trabalho no compromisso de trabalho foi estudada através de análise de regressão e isso implica que para cada aumento de uma unidade na política de RH, a 0,52 (coeficientes unstandardised) aumento no compromisso de trabalho está previsto e foi acabou como uma variável de maior impacto para prever compromisso de trabalho. Os coeficientes para Relacionamento (B = 0,330, sig = 0,000), Políticas de Recursos Humanos (B = 0,519, sig = 0,000), remuneração e benefícios (B = 0,386, sig = 0,000) e Crescimento Empregado (B = 0,290, sig = 0,001) foram significativamente diferente de 0, desde o seu valor de p era 0,000 que é menor do que 0,05. Os coeficientes para o Trabalho Autonomia (B = 0,154, SOG = 0,081) não foi estatisticamente diferente de zero, porque o seu valor-p é 0,081, que é maior do que 0,05. A implicação desta pesquisa vai ajudar os gestores a criar um ambiente de trabalho bem compatível concentrando-se em importantes construções de compatibilidade trabalho pessoa- que têm um possível efeito positivo no compromisso de trabalho e reduzindo, assim, a intenção de rotatividade dos empregados. Ainda mais aumentou compromisso de trabalho resultará em resultados do trabalho positivos, tais como a satisfação no trabalho e comprometimento organizacional
There have been given a much higher importance to employee commitment and retention since India is experiencing the highest attrition rate globally Economic Times, 2015¹. Hence, considering the factors of Person-job fit to interpret the impact towards work commitment is very well essential, especially in the current scenario. Work Commitment is a vital element in any organization which has outstanding impact on productivity and functioning and hence it is very much vital to have a committed workforce which is necessary in this competitive environment and tight labour market. In the same way, there is considerable amount of evidence that if P-J fit is high then it will have a direct impact on organization commitment also. Person-job fit is the compatibility between person's competency and abilities and the requirements of the job Zheng et al.². If there exists a mismatch between person-job fit then the consequences might result in poor work commitment, low job satisfaction and extremely lower involvement in the job. OBJECTIVE: This study analyzed the key factors that contribute to Person- job compatibility among IT workers and also analyzed the relationship and impact of Person- job compatibility towards work commitment. METHODS: Exploratory Factor Analysis (EFA) was used to filter the key factors initially, followed by a linear regression technique to determine the impact of Person- job compatibility factors in work commitment on a sample of 300 employees. EFA used Principal Component analysis for extraction and Promax for rotation. Finally regression analysis was carried out to predict the work commitment through statistically significant person-job compatibility variables. RESULTS: The impact of person-job compatibility on work commitment was studied through regression analysis and it imply that for every unit increase in HR Policy, a 0.52(unstandardised coefficients) increase in work commitment is predicted and it has been turned out as a most impacting variable to predict work commitment. The coefficients for Relationship (B =.330, sig =.000), HR Policies (B =.519, sig =.000), Pay and Benefits (B =.386, sig =.000) and Employee Growth (B =.290, sig =.001) were statistically significant, since its p-value is .000 which is smaller than .05. The coefficients for Work Autonomy (B =.154, sig = .081) was not statistically significant, since its p-value is 0.081 which is greater than.05. CONCLUSION: The major factors responsible for creating work commitment among IT employees are Relationship, HR Policies and strategies, Pay and benefits, Work autonomy and Employee growth. The most contributing regressors which accounts for creating work commitment are HR policies, Pay and benefits, Employee growth and work autonomy
Assuntos
Humanos , Masculino , Feminino , Recursos Humanos , Autonomia Profissional , Trabalho , Condições de Trabalho , Condições de Trabalho , Análise Fatorial , Satisfação no Emprego , Modelos Lineares , Estratégias de SaúdeRESUMO
Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is the predominant causative agent of hemorrhagic colitis in humans and is the cause of haemolytic uraemic syndrome and other illnesses. Cattle have been implicated as the main reservoir of this organism. Here, we evaluated the immunogenicity and protective efficacy of a DNA vaccine encoding conserved sequences of truncated EHEC factor for adherence-1 (efa-1') in a mouse model. Intranasal administration of plasmid DNA carrying the efa-1' gene (pVAXefa-1') into C57BL/6 mice elicited both humoral and cellular immune responses. In animals immunized with pVAXefa-1', EHEC-secreted protein-specific IgM and IgG antibodies were detected in sera at day 45. Anti-EHEC-secreted protein sIgA was also detected in nasal and bronchoalveolar lavages. In addition, antigen-specific T-cell-proliferation, IL-10, and IFN-γ were observed upon re-stimulation with either heat-killed bacteria or EHEC-secreted proteins. Vaccinated animals were also protected against challenge with E. coli O157:H7 strain EDL933. These results suggest that DNA vaccine encoding efa-1' have therapeutic potential in interventions against EHEC infections. This approach could lead to a new strategy in the production of vaccines that prevent infections in cattle.
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Toxinas Bacterianas/imunologia , Infecções por Escherichia coli/prevenção & controle , Escherichia coli O157/imunologia , Proteínas de Escherichia coli/imunologia , Vacinas contra Escherichia coli/imunologia , Vacinas de DNA/imunologia , Administração Intranasal , Animais , Anticorpos Antibacterianos/sangue , Carga Bacteriana , Toxinas Bacterianas/genética , Líquido da Lavagem Broncoalveolar/química , Proliferação de Células , Modelos Animais de Doenças , Infecções por Escherichia coli/imunologia , Escherichia coli O157/genética , Proteínas de Escherichia coli/genética , Vacinas contra Escherichia coli/administração & dosagem , Vacinas contra Escherichia coli/genética , Humanos , Imunoglobulina A Secretora/análise , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Interferon gama/metabolismo , Interleucina-10/metabolismo , Intestinos/microbiologia , Camundongos Endogâmicos C57BL , Cavidade Nasal/química , Plasmídeos , Linfócitos T/imunologia , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genéticaRESUMO
The influence of dietary fatty acids (FA) on mania-like behavior and brain oxidative damage were evaluated in rats. First generation of rats born and maintained under supplementation with soybean-oil (SO), fish-oil (FO) or hydrogenated-vegetable-fat (HVF), which are rich in n-6, n-3 and trans (TFA) FA, respectively, until adulthood, were exposed to an amphetamine (AMPH)-induced mania animal model to behavioral and biochemical evaluations. While AMPH caused hyperlocomotion in HVF and, to a less extent, in SO- and FO-groups, a better memory performance was observed in FO group. Among vehicle-groups, HVF increased reactive species (RS) generation and protein-carbonyl (PC) levels in cortex; FO reduced RS generation in hippocampus and decreased PC levels in hippocampus and striatum. Among AMPH-treated animals, HVF exacerbated RS generation in all evaluated brain areas and increased PC levels in cortex and striatum; FO reduced RS generation in hippocampus and decreased PC levels in hippocampus and striatum. FO was related to higher percentage of polyunsaturated fatty acids (PUFA) and docosahexaenoic acid (DHA) in cortex and striatum, while HVF was associated to higher incorporation of TFA in cortex, hippocampus and striatum, besides increased n-6/n-3 FA ratio in striatum. While a continuous exposure to TFA may intensify oxidative events in brain, a prolonged FO consumption may prevent mania-like-behavior; enhance memory besides decreasing brain oxidative markers. A substantial inclusion of processed foods, instead of foods rich in omega-3, in the long term is able to influence the functionality of brain structures related to behavioral disturbances and weaker neuroprotection, whose impact should be considered by food safety authorities and psychiatry experts.
Assuntos
Encéfalo/efeitos dos fármacos , Gorduras na Dieta/farmacologia , Comportamento Exploratório/efeitos dos fármacos , Ácidos Graxos/metabolismo , Atividade Motora/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Reconhecimento Psicológico/efeitos dos fármacos , Anfetamina , Animais , Transtorno Bipolar/induzido quimicamente , Transtorno Bipolar/dietoterapia , Transtorno Bipolar/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Gorduras na Dieta/uso terapêutico , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Gravidez , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
The current Western diet often provides considerable amounts of saturated and trans fatty acids (TFA), whose incorporation into neuronal membranes has been implicated in changes of brain neurochemical functions. Such influence has caused concerns due to precipitation of neuropsychiatric disorders, whose data are still unclear. Here we evaluated the influence of different fats on preference parameters for amphetamine (AMPH): adolescent rats were orally supplemented with soybean oil (SO, rich in n-6 FA, which was considered an isocaloric control group), fish oil (FO, rich in n-3 FA) and hydrogenated vegetable fat (HVF, rich in saturated and trans FA) from weaning, which were born of dams supplemented with the same fat from pregnancy and lactation. AMPH preference, anxiety-like symptoms and locomotor index were evaluated in conditioned place preference (CPP), elevated plus maze (EPM) and open-field (OF), respectively, while brain oxidative status was determined in cortex, striatum and hippocampus. HVF increased AMPH-CPP and was associated with withdrawal signs, as observed by increased anxiety-like symptoms. Moreover, SO and FO were not associated with AMPH preference, but only FO-supplemented rats did not show any anxiety-like symptoms or increased locomotion. FO supplementation was related to lower oxidative damages to proteins and increased CAT activity in striatum and hippocampus, as well as increased GSH levels in blood, while HVF was related to increased oxidative status. In conclusion, our study showed the harmful influence of TFA on AMPH-CPP and drug craving symptoms, which can be related to dopaminergic neurotransmission.
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Anfetamina/farmacologia , Comportamento Animal/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos trans/farmacologia , Animais , Condicionamento Clássico , Feminino , Ratos , Ratos WistarRESUMO
Because consumption of processed foods has increased in the last decades and so far its potential influence on emotionality and susceptibility to stress is unknown, we studied the influence of different fatty acids (FA) on behavioral and biochemical parameters after acute restrain stress (AS) exposure. Two sequential generations of female rats were supplemented with soybean oil (control group; C-SO), fish oil (FO) and hydrogenated vegetable fat (HVF) from pregnancy and during lactation. At 41days of age, half the animals of each supplemented group were exposed to AS and observed in open field and elevated plus maze task, followed by euthanasia for biochemical assessments. The HVF-supplemented group showed higher anxiety-like symptoms per se, while the C-SO and FO groups did not show these behaviors. Among groups exposed to AS, HVF showed locomotor restlessness in the open field, while both C-SO and HVF groups showed anxiety-like symptoms in the elevated plus maze, but this was not observed in the FO group. Biochemical evaluations showed higher lipoperoxidation levels and lower cell viability in cortex in the HVF group. In addition, HVF-treated rats showed reduced catalase activity in striatum and hippocampus, as well as increased generation of reactive species in striatum, while FO was associated with increased cell viability in the hippocampus. Among groups exposed to AS, HVF increased reactive species generation in the brain, decreased cell viability in the cortex and striatum, and decreased catalase activity in the striatum and hippocampus. Taken together, our findings show that the type of FA provided during development and growth over two generations is able to modify the brain oxidative status, which was particularly adversely affected by trans fat. In addition, the harmful influence of chronic consumption of trans fats as observed in this study can enhance emotionality and anxiety parameters resulting from stressful situations of everyday life, which can trigger more severe neuropsychiatric conditions.