Characterization of antimicrobial effect of organotin-based catalysts on diesel-biodiesel deteriogenic microorganisms.

Organotin compounds are applied in several industrial reactions and can present antifungal and antibacterial activities. Incorrect handling and storage practices of biodiesel and diesel-biodiesel blends can lead to microbial development, impacting its final quality. Concerning this problem, this work investigated the antimicrobial action of two organotin catalysts used in biodiesel production with four isolated microroorganisms (Bacillus pumilus, Pseudomonas aeruginosa, Pseudallescheria boydii, and Aureobasidium pullulans) and a pool of microorganisms (ASTM E1259 standard practice). Samples of soybean biodiesel with different concentrations of dibutyl tin dilaurate (catalyst 1) and di-n-butyl-oxo-stannane (catalyst 2) were prepared and added of mineral medium. The pool of microorganisms was inoculated and incubated at 30 °C and final biomass was weighted after 14 days. Thereafter, soybean biodiesel with catalyst 2 was used. Fungal biomass was weighted, and plate count was used to assess bacterial growth. Results show that catalysts 1 and 2 presented no inhibitory activity on the pool of microorganisms evaluated. A slight inhibitory activity was observed for B. pumilus and A. pullulans growth, but not for P. boydii, P. aeruginosa, or the pool of microorganisms. All experiment exhibited acidification higher than sterile control. Infrared analysis show less microbiological degradation products in the tin-protected fuel with ASTM inoculum. These results suggest that these tin-based catalysts show no toxic effect on native microbial population and a slight effect on some isolated microbial population in laboratory scale and for the first time shows that these organotin compounds can be employed safely as biodiesel catalyst. Graphical abstract.

Nitrogen source and pH interact and modulate lipase secretion in a non-clinical strain of Candida parapsilosis

Lipases (E.C. 3.1.1.3) are serine-hydrolases, and act on long chain fatty acid ester bonds. They exhibit specific and enantioselective activities, which are desirable for many industrial applications. This study aimed at screening and optimizing the production of lipases by wild yeast strains from a variety of substrates, as well as characterizing the enzyme. An initial selection was made in oxygenated oil-supplemented minimum medium, and the enzymatic activity of the supernatant was tested over p-nitrophenyl palmitate. One-hundred and twenty-four yeast strains from different substrates were tested, and twenty-three showed significantly higher lipolytic activity (p<0.01). One yeast in particular, QU110, showed best lipase production and therefore was selected for the optimization and characterization processes. This yeast exhibits enzyme secretion in initial pH 6.0, with olive oil and tryptone as carbon and nitrogen sources, respectively. There was a strong interaction between nitrogen source and initial pH, and pH 9.0seems to inhibit enzyme secretion. The crude enzyme (cell-free supernatant) shows stability in surfactants and n-hexane, but not in ethanol or methanol. A Response Surface Model was created and optimal enzyme activity conditions were observed at 36°C and pH 8.0. The lipase is appropriate for transesterification reactions, as the enzyme is more stable in strong apolar solvents than moderately apolar ones. Also, secretion by pH was not reported elsewhere, which should be further investigated and contribute for other yeast bioprocesses as well.

Positive and negative affect schedule: psychometric properties for the Brazilian Portuguese version.

This study is about the validity and item analysis for the Positive and Negative Affect Schedule (PANAS), respectively through the Exploratory Factor Analysis (principal components method) and the Partial Credit Model (PCM). The scale has been largely used in areas ranging from clinical to social psychology since its release in 1988 by Watson, Clark, and Tellegen. In order to assess validity and item properties (Item Response Theory paradigm), this is study administered PANAS to 354 respondents, 115 male and 239 female subjects, with an average age of 29.5 (SD = 10,18). The results show PANAS's excellent psychometric properties, with consistent dimensions and reliable item functioning, considering the Rasch measurement paradigm expressed in the PCM as an Item Response Theory model for polytomous data. The study considers important cultural issues and the results support more cautious translations for scales as well as further studies concerned with cross-cultural differences on the perception of affect states.

Dimensions of familial allocentrism in Brazilian mothers from state capitals and small cities.

This study focuses on 606 Brazilian women's cultural models regarding their relation with their family, as evaluated by the Family Allocentrism Idiocentrism Scale (FAS). The scale was translated into Portuguese, submitted to back-translation and adapted. Analyses of the scale's structure indicated that the best fit model involves two independent factors. Univariate GLM (General Linear Model) analyses showed that the place where mothers were raised presented a significant effect on their scores on factor 1 (normative familial allocentrism). Mothers raised on rural areas have higher scores on this factor, than the ones raised on urban areas. The opposite occurred with factor 2 (relational familial allocentrism). The set of evidences indicate that the FAS may be a bi-dimensional measure. One dimension would be part of a more stable and basic model of relation to family, constructed during development. The second dimension would be related to more recent experiences and would be more readily affected by socio-cultural context changes, including in acculturation processes.

Funcionamento Diferencial de Itens (DIF) e experiência de afeto: questões de gênero / Differential Item Functioning and affect: gender issues

O presente estudo teve por objetivo contemplar o critério de justiça dos itens da Escala de Afeto Positivo e Afeto Negativo (PANAS), considerando contribuições das últimas décadas sobre a evidência de diferenças de gênero na manifestação dos traços em questão. Com esse objetivo, a PANAS foi aplicada em 354 participantes, de ambos os sexos. Os dados foram avaliados sob o paradigma da TRI, segundo o modelo para itens politômicos sugerido por Andrich (1988), e o critério de justiça de acordo com o Funcionamento Diferencial de Itens, conforme os parâmetros sugeridos por Linacre (2011), comparando amostras com sujeitos do sexo feminino e masculino. As evidências do presente estudo apontam para itens que favorecem determinadas características dos grupos em questão(AU)

This article is an investigation into the justice criterion for the items of the Positive Affect and Negative Affect Schedule (PANAS) considering contributions from the last decades on gender differences as to emotion and affect experience. For this purpose, the PANAS was administered to 354 participants of both genders. Data was evaluated under the paradigm of IRT, according to the model of polytomous responses suggested by Andrich (1988), and the criterion of justice in accordance with the Differential Item Functioning on the parameters suggested by Linacre (2011) comparing male and female samples. Evidence indicates differential item functioning for specific items, favoring groups according to their characteristics(AU)

Funcionamento Diferencial de Itens (DIF) e experiência de afeto: questões de gênero / Differential Item Functioning and affect: gender issues

O presente estudo teve por objetivo contemplar o critério de justiça dos itens da Escala de Afeto Positivo e Afeto Negativo (PANAS), considerando contribuições das últimas décadas sobre a evidência de diferenças de gênero na manifestação dos traços em questão. Com esse objetivo, a PANAS foi aplicada em 354 participantes, de ambos os sexos. Os dados foram avaliados sob o paradigma da TRI, segundo o modelo para itens politômicos sugerido por Andrich (1988), e o critério de justiça de acordo com o Funcionamento Diferencial de Itens, conforme os parâmetros sugeridos por Linacre (2011), comparando amostras com sujeitos do sexo feminino e masculino. As evidências do presente estudo apontam para itens que favorecem determinadas características dos grupos em questão.

This article is an investigation into the justice criterion for the items of the Positive Affect and Negative Affect Schedule (PANAS) considering contributions from the last decades on gender differences as to emotion and affect experience. For this purpose, the PANAS was administered to 354 participants of both genders. Data was evaluated under the paradigm of IRT, according to the model of polytomous responses suggested by Andrich (1988), and the criterion of justice in accordance with the Differential Item Functioning on the parameters suggested by Linacre (2011) comparing male and female samples. Evidence indicates differential item functioning for specific items, favoring groups according to their characteristics.

Positive and negative affect schedule: psychometric properties for the Brazilian Portuguese version

This study is about the validity and item analysis for the Positive and Negative Affect Schedule (PANAS), respectively through the Exploratory Factor Analysis (principal components method) and the Partial Credit Model (PCM). The scale has been largely used in areas ranging from clinical to social psychology since its release in 1988 by Watson, Clark, and Tellegen. In order to assess validity and item properties (Item Response Theory paradigm), this is study administered PANAS to 354 respondents, 115 male and 239 female subjects, with an average age of 29.5 (SD = 10,18). The results show PANAS’s excellent psychometric properties, with consistent dimensions and reliable item functioning, considering the Rasch measurement paradigm expressed in the PCM as an Item Response Theory model for polytomous data. The study considers important cultural issues and the results support more cautious translations for scales as well as further studies concerned with cross-cultural differences on the perception of affect states (AU)

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Decomposição, liberação e volatilização de nitrogênio em resíduos culturais de mucuna-cinza (Mucuna cinerea) / Decomposition, release and volatilization of nitrogen from velvet bean (Mucuna cinerea) residues

As leguminosas possibilitam a incorporação biológica de nitrogênio aos sistemas de produção. Contudo, existe pouco conhecimento sobre a decomposição, liberação e volatilização de nitrogênioassociados à diferentes doses de seus resíduos. Objetivouse, neste trabalho avaliar a decomposição, a liberação e a volatilização de nitrogênio de diferentes doses de mucuna-cinza (Mucuna cinerea Piper & Tracy). O experimento constou de tratamentos com 12 (C12) ou 25 (C25) Mg ha-1 de composto orgânico: C12AV0 (sem leguminosa); C12AV4 (4 Mg ha-1 de resíduo); C12AV8 (8 Mg ha-1); C12AV12 (12 Mg ha-1); C25; AV12 (12 Mg ha-1) e testemunha absoluta. Adotou-se o delineamento de blocos casualizados e cinco repetições. Foram determinadas as taxas de decomposição do adubo verde e liberação de N, o teor de N-mineral no solo e a volatilização de N-NH3. A liberação de N (t½=28 dias) foi mais rápida que a decomposição do resíduo (t½=38 dias). Essa liberação de N eleva rapidamente os teores de N-mineral do solo e resulta também em maior elevação da volatilização de N-NH3. O incremento das doses de 8 para 12 Mg ha-1 de mucuna resultou em aumento mais que proporcional da volatilização acumulada de N-NH3, atingindo 30 kg ha-1 após 30 dias.

The use of leguminous species allows the biological incorporation of nitrogen into cropping systems. Nevertheless, there is little knowledge about the decomposition, release and volatilization of nitrogen associated with the decomposition of different quantities of residues. The objective of this study was to evaluate the decomposition of the biomass, the release and volatilization of nitrogen from different doses of velvet bean (Mucuna cinerea Piper & Tracy) residues. The treatments were established either with 12 (C12) or 25 (C25) Mg ha-1 of organic compost: C12AV0 (without residue); C12AV4 (4 Mg ha-1 of residue); C12AV8 (8 Mg ha-1); C12AV12 (12 Mg ha-1); C25; AV12 (12 Mg ha-1) and a control. The randomized block design was adopted with five repetitions. Mass dry matter decomposition and N release rate, the soil N-mineral content and N-NH3 volatilization were determined. N mineralization (t ½= 28 days) was faster than the decomposition of dry matter (t ½=38 days). This mineralization rapidly increased the soil mineral-N content and resulted in higher N-NH3 volatilization. However, the increase from 8 to 12 Mg ha-1 of velvet bean mass resulted in an overproportional increase of N-NH3 volatilization, which reached 30 kg ha-1 after 30 days.

Brazilian mothers' knowledge about home dangers and safety precautions: an initial evaluation.

Worldwide, unintentional injuries are a major cause of emergency department visits, hospitalization, permanent disability, and death among children. Today, unintentional injuries are the leading cause of death in children aged 1-14 years in South American countries, including Brazil and Argentina. The majority of unintentional injuries happen in or near the home, and researchers have pointed out that prevention efforts should include the active involvement of parents and caregivers. The ability to identify dangerous situations, products, and behaviors, and to provide suitable precautions, is important if parents are to provide a safe environment for their children as well as for themselves. Despite the overwhelming evidence concerning the relevance of the topic, few studies have focused on parenting knowledge about home safety. This is especially true in developing countries. The present work had three objectives. First, we evaluated the cultural adequacy of the illustrated version of the Home Inventory for Dangers and Safety Precautions (HIDSP-4) in a Brazilian context. Second, we evaluated Brazilian mothers' knowledge about home dangers and safety precautions (based on a convenience sample of 96 mothers resident in Rio de Janeiro). Finally, we analyzed associations between scores in the HIDSP-4 and sociodemographic variables (e.g., educational attainment, socioeconomic status (SES)). It was verified that the inventory suitably covers home dangers identified by Brazilian epidemiological studies on unintentional injuries, and presented satisfactory psychometric properties and cultural adequacy for Brazilian contexts. Brazilian mothers identified 62% of the dangers presented in the illustrations and provided suitable precautions for 26% of the dangers. These results indicate that mothers had some difficulty in identifying home dangers and even more difficulty providing suitable precautions for prevention or remediation of those dangers. Our correlation and regression analyses revealed that most of the variation of knowledge concerning dangers and safety precautions is not explained by variation in the educational attainment and SES of the mothers. Future directions are explored.