Correlation of in Vivo Relative Bioavailability to in Vitro Bioaccessibility for Arsenic in Household Dust from China and Its Implication for Human Exposure Assessment

Incidental ingestion of household dust is an important arsenic (As) exposure pathway for children. However, compared to soils, assessment of As relative bioavailability (RBA) in household dust is limited. In this study, As-RBA in 12 household dust samples (7–38 mg kg^–1) was measured using an in vivo mouse model and compared to As bioaccessibility determined using 4 assays [Solubility Bioaccessibility Research Consortium method (SBRC), in vitro gastrointestinal method (IVG), Deutsches Institut für Normunge.V. method (DIN), and physiologically based extraction test (PBET)]. Arsenic RBA ranged from 21.8 ± 1.6 to 85.6 ± 7.2% with samples containing low Fe and high total organic carbon content having higher As-RBA. Strong in vivo–in vitro correlations (IVIVC) were found between As-RBA and As bioaccessibility for SBRC and DIN (<i>r</i>² = 0.63–0.85), but weaker ones were obtained for IVG and PBET (<i>r</i>² = 0.29–0.55). The developed IVIVC for SBRC and DIN were used to calculate As-RBA based on As bioaccessibility for an additional 12 household dust samples. Although As bioaccessibility differed significantly (up to 7.7-fold) based on in vitro methods, predicted As-RBA was less variable (up to 3.0-fold) when calculated using As bioaccessibility data and the corresponding IVIVC. Our data suggested that both SBRC and DIN had potential to assess As bioavailability in household dust samples; however, additional research is needed

A estratégia organizacional subjacente à gestão de incentivos em empresas do setor secundário: estudo de caso

Dissertação de mestrado em Gestão de Recursos HumanosCom o presente estudo objetiva-se analisar as percepções e resultados estratégicos consequentes da aplicação da prática de Remuneração Variável através do Prêmio por Objetivo, segundo a percepção dos trabalhadores que são elegíveis ao recebimento do prêmio financeiro, nomeadamente, pessoas com cargo técnico, operadores, líderes de equipes, supervisor e a percepção estratégica de um Chefe de Divisão de Recursos Humanos. É intenção deste estudo, compreender quais os resultados estratégicos no que tange à produtividade, inovação, satisfação, desempenho e Melhoria do Clima Organizacional que a adoção da prática poderá trazer de impacto para o negócio, a sua praticabiliadade e a complementaridade trazida por outras práticas de Gestão de Recursos Humanos. Desta feita, para a análise do mesmo, assume-se uma postura epistemológica interpretativa e qualitativa dos fatos, sendo que o objetivo é obter respostas através de como cada trabalhador percepciona a realidade no dia a dia da organização diante dos objetivos estratégicos determinados. Através dos discursos, é possível obter, de forma mais próxima, dados relevantes para a conclusão deste estudo. O estudo realizou-se numa organização de caráter privado, de origem Alemã, nomeadamente Volkswagen Autoeuropa, situada no concelho de Palmela em Portugal, onde foi possível realizar 10 entrevistas á trabalhadores dos cargos acima mencionados. É importante ressaltar a complexidade deste sistema, que teve os resultados demonstrados em um ambiente com uma forte cultura organizacional e que junto com outras práticas de Recursos Humanos, principalmente a avaliação de desempenho, fazem parte de um sistema de alta performance orientados os objetivos estratégicos organizacionais. Foi possível constatar o impacto positivo da prática da Remuneração Variável através do prêmio por objetivo nos índices de produtividade, no desempenho na melhoria do clima organizacional e na cooperação entre pares. Porém para a inovação e satisfação não foi possível perceber o impacto da ferramenta.The aim of this study is to analyze the perceptions and strategic outputs resulting from the application of the Variable Remuneration practice through the Profit Sharing, according to the perception of the workers who are eligible to receive the financial award, namely, people with technical positions, Team leaders, supervisor and the strategic insight of a Head of Human Resources Division. It is the intention of this study to understand the strategic results regarding productivity, innovation, satisfaction, performance and Organizational Climate Improvement that the adoption of the practice may bring as impact to the business, its practicability and the complementarity by other Human Resources Management practices. In order to analyze it, an interpretative and qualitative epistemological posture of the facts is assumed. The objective is to obtain answers through how each worker perceives the reality in the day to day of the organization in front of the determined strategic objectives. Through the speeches, it is possible to obtain, more closely, relevant data for the conclusion of this study. The study was carried out in a private organization of German origin, namely Volkswagen Autoeuropa, located in the municipality of Palmela in Portugal, where it was possible to carry out 10 interviews with workers of the aforementioned positions. It is important to emphasize the complexity of this system, which had the results demonstrated in an environment with a strong organizational culture and that along with other Human Resources practices, mainly evaluation performance system, are part of a high performance system oriented to organizational strategic objectives. It was possible to verify the positive impact of the practice of Variable Remuneration through the Profit Sahring in productivity indices, performance in improving the organizational climate and in peer cooperation. However for innovation and satisfaction it was not possible to have the impact of the tool perceived

Optimal number of reference genes for normalization in <i>Frankliniella occidentalis.</i>

<p>The pairwise variation (Vn/Vn+1) was analyzed between normalization factors NFn and NFn+1 by geNorm program to determine the optimal number of reference genes. Values <0.15 indicate that additional genes are not required for the normalization of gene expression.</p

<i>In vitro</i> US experiments.

<p>Images of SonoVue® and Fe₃O₄-MBs under the mode of CnTI™ and Flash: (A) In the first half of the tube, in CnTI® mode, SonoVue® showed high echo; in the second half, in Flash mode, the SonoVue® microbubbles broke and the enhanced signal generated by the microbubbles changed to anecho (white arrow). (B) Under the same imaging strategy change, the signal of Fe₃O₄-MBs tube had little change (white arrow).</p

SNR time courses of MRI from SonoVue® and Fe₃O₄-MBs.

<p>Figure A shows the SNR time course in ROI during SonoVue® injection and Figure B shows the SNR time course when using Fe₃O₄-MBs.</p

<i>In vitro</i> MRI experiments.

<p>The <i>in vitro</i> MR images of different volume fraction of SonoVue® and Fe₃O₄-MBs: (A). 1: sodium chloride solution (0.9% w/v), 2–4: SonoVue® with different volume fraction (1.75%, 3.5%, 7.0%). 5–7: Fe₃O₄-MBs with different volume fraction (1.75%, 3.5%, 7.0%). (B) an approximately linear relationship was observed in SonoVue® (r = −0.982, P<0.05) between SNR and microbubble volume fraction. (C) an approximately linear relationship was observed in Fe₃O₄-MBs (r = −0.929, P<0.05) between SNR and microbubble volume fraction.</p

SNR time courses of the same mouse tumor in US by using SonoVue® and Fe₃O₄-MBs.

<p>Figure A shows the SNR time course in ROI during SonoVue® injection and Figure B shows the SNR time course when using Fe₃O₄-MBs injection.</p

Correlation between the US and MRI.

<p>Figure A shows the signal strength correlation between US and MRI in 600 seconds of enhancement when using SonoVue® (r = −0.733, P<0.05). Figure B shows the signal strength correlation between US and MRI in 600 seconds of enhancement when using Fe₃O₄-MBs (r = −0.903, P<0.05).</p

Primer sequences and amplicon characteristics of the candidate reference genes.

a<p>Length of the amplicon; ^bmelt temperature; ^cReal-time qPCR efficiency (calculated from the standard curve); ^dRegression coefficient.</p><p>Primer sequences and amplicon characteristics of the candidate reference genes.</p

Expression stability of the candidate reference genes as calculated by the Geomean method of RefFinder.

<p>A lower Geomean ranking indicates more stable expression. Expression stability of reference genes in the following samples: A) different developmental stages of <i>Frankliniella occidentalis</i>; B) <i>F. occidentalis</i> exposed to high temperatures; C) <i>F. occidentalis</i> exposed to low temperatures.</p