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1.
Front Sociol ; 9: 1230567, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38799208

RESUMO

Migrant integration trajectories have become more complex, open, uncertain, and continuously changing, over time. For young migrants, their integration endeavour intersects with their process of transition to adulthood, a double transition that poses additional challenges. Recent theoretical perspectives such as "liquid integration" aim at focusing on the dynamic, processual, and temporal nature of migrant integration. The present article focuses on the dynamic interplay of obstacles and enablers that, over time, interact to construct complex, often non-linear, and open-ended integration and coming of age trajectories of young migrants (aged from 18 to 30 years) coming from outside the European Union (EU) to EU countries. Empirical results from the H2020 MIMY (Empowerment through liquid Integration of Migrant Youth in vulnerable conditions) research project in Luxembourg will be presented. In order to address the goal of the research, qualitative data were gathered by means of N = 38 interviews with young migrants with different migratory paths, characteristics and experiences, and specifically included: young migrants from non-EU Portuguese-speaking countries (N = 16), refugees living in reception centres (N = 15), migrants who since arriving in Luxembourg have become publicly visible (N = 7). Content analysis of the interviews allowed a twofold purpose: (1) capturing the unfolding of intersectional integration obstacles that over time play a decisive role in the building of conditions of vulnerability of the double transition under analysis; (2) capturing the multidimensional resources that interactively build up to give rise to resilient and empowering integration and coming of age experiences. The identification of decisive multidimensional obstacles and resources present in the integration endeavour during the process of coming of age allowed us to capture differentiated routes of vulnerability, on the one hand, and resilience/ empowerment on the other. Key ingredients of both vulnerable and more resilient and empowering integration and coming of age trajectories are identified as well as their relational dynamics, enabling to address key challenges for the resilience and empowerment of young migrants in the process of negotiating their transition to adulthood amidst their integration challenges in the Luxembourgish society.

2.
Perspect Psychol Sci ; : 17456916231208367, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350096

RESUMO

Psychological science tends to treat subjective well-being and happiness synonymously. We start from the assumption that subjective well-being is more than being happy to ask the fundamental question: What is the ideal level of happiness? From a cross-cultural perspective, we propose that the idealization of attaining maximum levels of happiness may be especially characteristic of Western, educated, industrial, rich, and democratic (WEIRD) societies but less so for others. Searching for an explanation for why "happiness maximization" might have emerged in these societies, we turn to studies linking cultures to their eco-environmental habitat. We discuss the premise that WEIRD cultures emerged in an exceptionally benign ecological habitat (i.e., faced relatively light existential pressures compared with other regions). We review the influence of the Gulf Stream on the Northwestern European climate as a source of these comparatively benign geographical conditions. We propose that the ecological conditions in which WEIRD societies emerged afforded them a basis to endorse happiness as a value and to idealize attaining its maximum level. To provide a nomological network for happiness maximization, we also studied some of its potential side effects, namely alcohol and drug consumption and abuse and the prevalence of mania. To evaluate our hypothesis, we reanalyze data from two large-scale studies on ideal levels of personal life satisfaction-the most common operationalization of happiness in psychology-involving respondents from 61 countries. We conclude that societies whose members seek to maximize happiness tend to be characterized as WEIRD, and generalizing this across societies can prove problematic if adopted at the ideological and policy level.

3.
Risk Anal ; 33(5): 877-92, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22967223

RESUMO

The Monte Carlo (MC) simulation approach is traditionally used in food safety risk assessment to study quantitative microbial risk assessment (QMRA) models. When experimental data are available, performing Bayesian inference is a good alternative approach that allows backward calculation in a stochastic QMRA model to update the experts' knowledge about the microbial dynamics of a given food-borne pathogen. In this article, we propose a complex example where Bayesian inference is applied to a high-dimensional second-order QMRA model. The case study is a farm-to-fork QMRA model considering genetic diversity of Bacillus cereus in a cooked, pasteurized, and chilled courgette purée. Experimental data are Bacillus cereus concentrations measured in packages of courgette purées stored at different time-temperature profiles after pasteurization. To perform a Bayesian inference, we first built an augmented Bayesian network by linking a second-order QMRA model to the available contamination data. We then ran a Markov chain Monte Carlo (MCMC) algorithm to update all the unknown concentrations and unknown quantities of the augmented model. About 25% of the prior beliefs are strongly updated, leading to a reduction in uncertainty. Some updates interestingly question the QMRA model.


Assuntos
Bacillus cereus/crescimento & desenvolvimento , Teorema de Bayes , Microbiologia de Alimentos , Medição de Risco , Algoritmos , Bacillus cereus/genética , Modelos Teóricos , Método de Monte Carlo
4.
Integr Psychol Behav Sci ; 57(2): 518-546, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36085348

RESUMO

The sense of belonging can be defined as a highly subjective and dynamic feeling of acceptance, inclusion, and connectedness to a specific contextual entity. Perceiving belongingness to others is positively related to psychological well-being, happiness, or higher self-esteem. The present contribution examined how the sense of belonging to spatial, social, and cultural entities evolves over the migration process of Portuguese first-generation migrants and their second-generation offspring residing in Luxembourg. The current study drew on the qualitative content analysis of ten semi-structured interviews, carried out with ten Portuguese migrant family dyads (one parent and one adult child per dyad). The results affirmed that the sense of belonging showed to be a complex and multi-faceted concept and highly shaped by specific contexts. The initially unfamiliar Luxembourgish context became a familiar setting and even a "home" over time. While the older generation presented noticeable belongingness to Luxembourg as a homeland, their affiliation to the Luxembourgish community and culture remained rather low. Simultaneously, they preserved a high connectedness to the Portuguese culture as well as to fellow Portuguese migrants living in the Grand Duchy. The younger generation expressed a much more pronounced attachment to Luxembourg, since they perceived belongingness to the Luxembourgish spatial, social, and (multi)cultural milieu. In addition to this, a certain affiliation to the Portuguese culture and language could be discerned. Although some factors, which might have contributed to this evolution, could be identified in the present study, one can assume that there are significantly more that have not been addressed yet.


Assuntos
Migrantes , Adulto , Humanos , Luxemburgo , Portugal , Pais , Idioma
5.
Risk Anal ; 32(3): 395-415, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22043854

RESUMO

Assessing within-batch and between-batch variability is of major interest for risk assessors and risk managers in the context of microbiological contamination of food. For example, the ratio between the within-batch variability and the between-batch variability has a large impact on the results of a sampling plan. Here, we designed hierarchical Bayesian models to represent such variability. Compatible priors were built mathematically to obtain sound model comparisons. A numeric criterion is proposed to assess the contamination structure comparing the ability of the models to replicate grouped data at the batch level using a posterior predictive loss approach. Models were applied to two case studies: contamination by Listeria monocytogenes of pork breast used to produce diced bacon and contamination by the same microorganism on cold smoked salmon at the end of the process. In the first case study, a contamination structure clearly exists and is located at the batch level, that is, between batches variability is relatively strong, whereas in the second a structure also exists but is less marked.


Assuntos
Microbiologia de Alimentos , Medição de Risco/estatística & dados numéricos , Análise de Variância , Animais , Teorema de Bayes , Manipulação de Alimentos , Humanos , Listeria monocytogenes/isolamento & purificação , Listeria monocytogenes/patogenicidade , Produtos da Carne/microbiologia , Modelos Estatísticos , Salmão/microbiologia , Sus scrofa
6.
Integr Psychol Behav Sci ; 56(1): 1-16, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35106707

RESUMO

This Special Issue aims to shed light on the undetermined nature of intergenerational trajectories. Indeterminacy has been suggested to the author as an avenue to tackle the dynamic aspect -which entails looking at tensions in an unfolding process- of intergenerationality. We present the paper in this Special Issue by insisting on their main contributions, we identify HOW they define the concept of generation, particularly in reference to indeterminacy.

7.
PLoS One ; 17(9): e0274293, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36174067

RESUMO

During the Covid-19 pandemic, older people have been in the spotlight of the public debate. Given their higher risk of severe outcomes of the disease, they have been described as especially vulnerable and as a burden to others and society. We thus wanted to investigate how older people's perception of their own age, that is their subjective age, as well as their Covid-19 related risks and worries were related during the pandemic and whether these relationships varied according to participants' subjective health. We used data from the longitudinal CRISIS study which was conducted in the Grand-Duchy of Luxembourg in June and October 2020. Participants were aged 60-98 and responded on questionnaires regarding their subjective age, worry of falling ill with Covid-19, perceived risk of contracting the virus, perceived risk of falling seriously ill if they contracted Covid-19, as well as their subjective health and covariates. Three cross-lagged panel models were constructed to explore the longitudinal, bidirectional relationships between the variables. Cross-sectionally, a higher subjective age was related to more perceived risk of a serious course of disease. Longitudinally, subjective age and worry did not show any significant association over time, and neither did subjective age and perceived risk of contracting the virus. However, subjective health significantly moderated the relationship of worry and subjective age, showing different trajectories in the relationship depending on whether subjective health was good or bad. Higher perceived risk of falling seriously ill increased subjective age over time. Again, subjective health moderated this relationship: the perceived risk of falling seriously ill affected subjective age only for those with better subjective health. Our findings show the interactive relationship between subjective age and Covid-19 related cognitions and emotions and provide guidance for identifying older people that are most susceptible for negative age-related communication during the pandemic.


Assuntos
COVID-19 , Pandemias , Idoso , COVID-19/epidemiologia , Cognição , Autoavaliação Diagnóstica , Emoções , Humanos
8.
Food Chem ; 374: 131623, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34872793

RESUMO

In a risk assessment perspective, this work aims to assess the bioaccessibility of PCBs in meat. A standardised in vitro static digestion protocol was set up and coupled with extraction, clean-up and GC × GC-ToF/MS multianalyte method to monitor the fate of PCBs in meat during digestion. Starting with spiked meat, PCB bioaccessibility in 11% fat medium-cooked meat varied in adults from 20.6% to 30.5% according to congeners. PCB bioaccessibility increased to 44.2-50.1% in 5% fat meat and decreased to 6.2-9.1% and to 14.6-19.4% in digestion conditions mimicking infants and elderly, respectively. Intense cooking also decreased PCB bioaccessibility to 18.0-26.7%. Bioaccessibility data obtained with spiked meat were validated with measurements carried out in incurred meat samples. Finally, mean uptake distributions are obtained from a modular Bayesian approach. These distributions feature a lower mode when the fat content is higher, the meat is well-done cooked, and the consumers are older.


Assuntos
Bifenilos Policlorados , Idoso , Teorema de Bayes , Transporte Biológico , Culinária , Humanos , Carne/análise , Bifenilos Policlorados/análise
9.
Risk Anal ; 31(7): 1141-55, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21231950

RESUMO

Stakeholders making decisions in public health and world trade need improved estimations of the burden-of-illness of foodborne infectious diseases. In this article, we propose a Bayesian meta-analysis or more precisely a Bayesian evidence synthesis to assess the burden-of-illness of campylobacteriosis in France. Using this case study, we investigate campylobacteriosis prevalence, as well as the probabilities of different events that guide the disease pathway, by (i) employing a Bayesian approach on French and foreign human studies (from active surveillance systems, laboratory surveys, physician surveys, epidemiological surveys, and so on) through the chain of events that occur during an episode of illness and (ii) including expert knowledge about this chain of events. We split the target population using an exhaustive and exclusive partition based on health status and the level of disease investigation. We assume an approximate multinomial model over this population partition. Thereby, each observed data set related to the partition brings information on the parameters of the multinomial model, improving burden-of-illness parameter estimates that can be deduced from the parameters of the basic multinomial model. This multinomial model serves as a core model to perform a Bayesian evidence synthesis. Expert knowledge is introduced by way of pseudo-data. The result is a global estimation of the burden-of-illness parameters with their accompanying uncertainty.


Assuntos
Infecções por Campylobacter/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Medição de Risco/métodos , Algoritmos , Teorema de Bayes , Prova Pericial , Humanos , Modelos Estatísticos , Método de Monte Carlo , Prevalência , Probabilidade
10.
Eur J Ageing ; 18(3): 299-310, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34483795

RESUMO

The risk of loneliness for migrants, particularly in older age, has been documented across multiple studies. Migration is a life-changing transition. While often retaining links to their country of origin, an important developmental task for migrants is the establishment of bonds in the receiving country. Drawing on recent studies, I will explore the role of cultural and intergenerational belonging in order to identify both protective and risk factors regarding loneliness in middle and older age in a sample of first-generation immigrants from Portugal living in Luxembourg. The sample comprises N = 131 participants (51.9% female) between the ages of 41 and 80 (M = 56.08; SD = 7.80) who have on average spent M = 31.71 years (SD = 8.81) in Luxembourg and raised children in Luxembourg. They took part in the IRMA project ('Intergenerational Relations in the Light of Migration and Ageing') which was funded by the Fonds National de la Recherche Luxembourg. A standardised questionnaire assessed socio-demographic data, aspects of cultural belonging (i.e. cultural attachment to both countries, bicultural identity orientation, acculturative stress), intergenerational belonging (i.e. family cohesion, family conflict, perceived intergenerational value consensus) and perceived loneliness. Results showed that while cultural and intergenerational belonging were protective factors, the strongest predictors for participants' perceived loneliness were cultural identity conflict and, even more so, intergenerational conflict. Our findings suggest that establishing roots and bonds in the host country is a protective factor against loneliness, whereas the feeling of not fitting in is a strong risk factor.

11.
Front Public Health ; 9: 679711, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34327186

RESUMO

Ageism in media and society has increased sharply during the Covid-19-crisis, with expected negative consequences for the health and well-being of older adults. The current study investigates whether perceived ageism during the crisis longitudinally affects how people perceive their own aging. In June 2020, N = 611 older adults from Luxembourg [aged 60-98 years, Mage (SD) = 69.92(6.97)] participated in a survey on their perception of the crisis. In October 2020, N = 523 participated in a second measurement occasion. Participants reported on perceived ageism during the crisis in different domains, their self-perceptions of aging and subjective age. In latent longitudinal regression models, we predicted views on aging at T2 with perceived ageism at T1, while controlling for baseline views on aging and covariates. Perceived ageism at T1 increased self-perceptions of aging as social loss and yielded a trend for physical decline, while there were no effects on subjective age and self-perceptions of aging as continued growth. Views on aging are powerful predictors of well-being and health outcomes in later life. Our data suggest that being the target of ageism during the crisis negatively affects older adults' self-perceptions of aging and this impact may be felt beyond the current crisis.


Assuntos
Etarismo , COVID-19 , Idoso , Envelhecimento , Humanos , Luxemburgo , Percepção , SARS-CoV-2
12.
Eur J Ageing ; 18(2): 173-184, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33948107

RESUMO

In the Covid-19 pandemic, being older means being in a special focus: Probabilities for severe infections and mortality rise with increasing age and protective measures for this population group have been increased. This was accompanied by public discourse that portrayed older adults stereotypically as vulnerable and frail but also highlighted the hardships younger people have to endure to protect them. Given the possibly detrimental effects of ageism on individuals and societies, we were interested in older adults' perception of ageism in the Corona-crisis and its relation to their health and well-being. Furthermore, we were interested in subjective aging variables as moderators in the ageism-health relationship. In June 2020, N = 611 independently living people aged 60 + from the Grand Duchy of Luxembourg were recruited via a survey research institute and interviewed online or by phone. They reported on perceived ageism in different contexts, their life satisfaction, subjective health, subjective age and self-perceptions of aging. Depending on context, ageism was perceived by around 20% of participants, and overall negatively related to subjective health and life satisfaction after the onset of the pandemic. Moderated hierarchical regressions showed that a younger subjective age buffered the negative effect of ageism on subjective health, while perceiving aging as social loss increased its effect on life satisfaction. We discuss the importance of addressing and reducing ageism (not only) in times of crisis and the consequences for individuals and societies.

13.
Regul Toxicol Pharmacol ; 58(3): 482-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20804806

RESUMO

Methylmercury (MeHg) is a bioaccumulative environmental toxin that exerts its effect on fetal and infant neurodevelopment. Mercury concentration in hair is a good biomarker of MeHg accumulation in the body, with seafood being the main source of MeHg in humans. Therefore, modeling the link between food intake and mercury concentration in hair is a key step in assessing the risk of MeHg exposure. Using repeated measurements of diet and mercury concentration in hair, we studied 125 French pregnant women who consumed seafood (e.g., fish, mollusks and crustaceans) and compared their individual estimated dietary MeHg intakes with their hair mercury concentrations. We used a one-compartment toxicokinetic model for these comparisons. We integrated and estimated the between-person variability in MeHg half-life into the model. In a second model, we took into account an intra-individual MeHg intake variability to improve the performance of the toxicokinetic model.


Assuntos
Dieta , Contaminação de Alimentos , Cabelo/química , Cabelo/efeitos dos fármacos , Mercúrio/análise , Compostos de Metilmercúrio/análise , Compostos de Metilmercúrio/toxicidade , Adulto , Animais , Biomarcadores , Simulação por Computador , Exposição Ambiental , Feminino , Peixes , Cabelo/fisiologia , Meia-Vida , Humanos , Compostos de Metilmercúrio/administração & dosagem , Compostos de Metilmercúrio/metabolismo , Modelos Estatísticos , Nível de Efeito Adverso não Observado , Gravidez , Medição de Risco , Alimentos Marinhos , Adulto Jovem
14.
Integr Psychol Behav Sci ; 54(1): 72-103, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31342315

RESUMO

The present investigation focused on cultural identity and the dealing with the belonging to different cultural frames as a migrant in a highly culturally diverse context by comparing two generations of Portuguese families living in Luxembourg. Quantitative standardized questionnaires complemented by in-depth qualitative interviews with parent-child dyads were used in order to assess possible (dis)similarities between first generation Portuguese immigrant parents and their adult children (i.e. second generation) concerning their cultural identities. Generational differences were found regarding the dealing with several cultural frames, language competences and attachment to both discussed cultures. Adult children were more prone to find themselves in a "compatible" identity orientation, compared to the parental generation. Yet, when focussing specifically on the second generation, qualitative data highlighted some issues regarding the perceived views of others on one's own cultural belonging and the perception of a certain sense of cultural identity denial from others. Our findings contribute to the existing theoretical literature on cultural identity by elucidating some major differences between immigrant parents and their adult children on how they enact the sense of belonging and the dealing with multiple cultural frames on a daily-life basis.


Assuntos
Diversidade Cultural , Cultura , Emigrantes e Imigrantes , Identificação Social , Adulto , Filhos Adultos , Idoso , Feminino , Humanos , Luxemburgo , Masculino , Pessoa de Meia-Idade , Pais , Portugal , Pesquisa Qualitativa
15.
Integr Psychol Behav Sci ; 54(2): 269-285, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32367374

RESUMO

This paper aims at overcoming the following limits of gerontagogy -particularly with regard to Lemieux's model: referencing chronological age; delimitating elders' learning in reference to traits (styles, needs, behaviors, etc.) in contrast to children's learning; overlooking the aging aspect. To do so, we propose to integrate aging and intergenerationality into gerontagogy from a sociocultural, dialogical and historical approach. This establishes the basis for an intergenerational and dialogical approach to elders' learning.


Assuntos
Envelhecimento , Aprendizagem , Idoso , Criança , Humanos
16.
Res Synth Methods ; 10(3): 343-359, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30353974

RESUMO

The mixed treatment comparison (MTC) method has been proposed to combine results across trials comparing several treatments. MTC allows coherent judgments on which of the treatments is the most effective. It produces estimates of the relative effects of each treatment compared with every other treatment by pooling direct and indirect evidence. In this article, we explore how this methodological framework can be used to rank a large number of agricultural crop species from yield data collected in field experiments. Our approach is illustrated in a meta-analysis of yield data obtained in 67 field studies for 36 different bioenergy crop species. The considered dataset defines a network of comparisons of crop species. We introduce several Bayesian MTC models based on baseline treatment contrasts and evaluate the practical advantages of these models to produce yield ratio estimates. We explore the consistency of some estimates by node-splitting and compare our results to those obtained with a classical two-way linear mixed model. Results reveal that the model showing the lowest deviance information criterion (DIC) includes both study random effects and study-specific residual variances. But all the tested models including study random effects lead to similar yield ratio estimates. The proposed Bayesian framework allows an in-depth analysis of the uncertainty in the species ranking.


Assuntos
Agricultura/métodos , Produtos Agrícolas , Projetos de Pesquisa , Algoritmos , Teorema de Bayes , Biocombustíveis , Simulação por Computador , Cruzamentos Genéticos , Bases de Dados Factuais , Europa (Continente) , Modelos Lineares , Cadeias de Markov , Método de Monte Carlo , Estados Unidos
17.
Risk Anal ; 28(2): 557-71, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18419669

RESUMO

A novel approach to the quantitative assessment of food-borne risks is proposed. The basic idea is to use Bayesian techniques in two distinct steps: first by constructing a stochastic core model via a Bayesian network based on expert knowledge, and second, using the data available to improve this knowledge. Unlike the Monte Carlo simulation approach as commonly used in quantitative assessment of food-borne risks where data sets are used independently in each module, our consistent procedure incorporates information conveyed by data throughout the chain. It allows "back-calculation" in the food chain model, together with the use of data obtained "downstream" in the food chain. Moreover, the expert knowledge is introduced more simply and consistently than with classical statistical methods. Other advantages of this approach include the clear framework of an iterative learning process, considerable flexibility enabling the use of heterogeneous data, and a justified method to explore the effects of variability and uncertainty. As an illustration, we present an estimation of the probability of contracting a campylobacteriosis as a result of broiler contamination, from the standpoint of quantitative risk assessment. Although the model thus constructed is oversimplified, it clarifies the principles and properties of the method proposed, which demonstrates its ability to deal with quite complex situations and provides a useful basis for further discussions with different experts in the food chain.


Assuntos
Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Animais , Teorema de Bayes , Campylobacter/patogenicidade , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/transmissão , Simulação por Computador , Qualidade de Produtos para o Consumidor , Contaminação de Alimentos/análise , França/epidemiologia , Incidência , Modelos Biológicos , Aves Domésticas/microbiologia , Medição de Risco , Software
18.
Integr Psychol Behav Sci ; 51(2): 205-222, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28190147

RESUMO

Intergenerational family relations are embedded in family cultures which influence how families regulate their relations over the whole life span with regard to key issues, such as autonomy and relatedness, or support exchange and reciprocity, and which may vary inter- and intraculturally. Migrant families undoubtedly face a special situation as values and expectations from the culture of origin and from the host cultural context might differ. Not much is known yet about how migrant families adapt their family cultures to the host cultural context. The present article will focus on aspects of intergenerational family regulation by taking into account family cultures of migrant compared to non-migrant families in a life span perspective. We will illustrate our theoretical outline by presenting first results from the IRMA-study comparing Luxembourgish and Portuguese immigrant families living in Luxembourg. We focus on issues of family cohesion, enmeshment and normative expectations regarding adult children's support for their ageing parents, by drawing both on quantitative questionnaire as well as qualitative interview data. Implications for the experience of ambivalence and conflicts as well as well-being of family members from both generations will be discussed.


Assuntos
Envelhecimento/psicologia , Cultura , Emigração e Imigração , Família/psicologia , Relação entre Gerações , Adulto , Criança , Feminino , Humanos , Luxemburgo , Masculino , Modelos Psicológicos , Portugal , Pesquisa Qualitativa , Valores Sociais , Inquéritos e Questionários
19.
Food Chem Toxicol ; 110: 251-261, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29061317

RESUMO

In this paper, exposure to Polychlorinated biphenyls (PCBs) related to bovine meat consumption is assessed based on multiples sources of data, namely data collected within the national research project "SoMeat" that objectively assesses the potential risks and benefits of organic and conventional food production systems in terms of contaminants respective contents. The work focuses on dioxin like PCBs in bovine meat in France. A modular Bayesian approach is proposed including measures after production, effect of cooking, levels and frequency of consumption and effect of digestion. In each module, a model is built and prior information can be integrated through previously acquired data commonly used in food risk assessment or vague priors. The output of the global model is the exposure including both production modes (organic and conventional) for three different cooking intensities (rare, medium, and well-done), before digestion and after digestion. The main results show that organic meat is more contaminated than conventional meat in mean after production stage and after cooking although cooking reduces the contamination level. This work is a first step of refined risk assessment integrating different steps such as cooking and digestion in the context of chemical risk assessment similarly to current microbiological risk assessments.


Assuntos
Criação de Animais Domésticos/métodos , Contaminação de Alimentos/análise , Carne/análise , Bifenilos Policlorados/análise , Animais , Bovinos , Culinária , Digestão , França , Humanos , Bifenilos Policlorados/metabolismo
20.
Int J Food Microbiol ; 192: 124-41, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25440556

RESUMO

Aseptic-Ultra-High-Temperature (UHT) products are manufactured to be free of microorganisms capable of growing in the food at normal non-refrigerated conditions at which the food is likely to be held during manufacture, distribution and storage. Two important phases within the process are widely recognised as critical in controlling microbial contamination: the sterilisation steps and the following aseptic steps. Of the microbial hazards, the pathogen spore formers Clostridium botulinum and Bacillus cereus are deemed the most pertinent to be controlled. In addition, due to a relatively high thermal resistance, Geobacillus stearothermophilus spores are considered a concern for spoilage of low acid aseptic-UHT products. A probabilistic exposure assessment model has been developed in order to assess the aseptic-UHT product failure rate associated with these three bacteria. It was a Modular Process Risk Model, based on nine modules. They described: i) the microbial contamination introduced by the raw materials, either from the product (i.e. milk, cocoa and dextrose powders and water) or the packaging (i.e. bottle and sealing component), ii) the sterilisation processes, of either the product or the packaging material, iii) the possible recontamination during subsequent processing of both product and packaging. The Sterility Failure Rate (SFR) was defined as the sum of bottles contaminated for each batch, divided by the total number of bottles produced per process line run (10(6) batches simulated per process line). The SFR associated with the three bacteria was estimated at the last step of the process (i.e. after Module 9) but also after each module, allowing for the identification of modules, and responsible contamination pathways, with higher or lower intermediate SFR. The model contained 42 controlled settings associated with factory environment, process line or product formulation, and more than 55 probabilistic inputs corresponding to inputs with variability conditional to a mean uncertainty. It was developed in @Risk and run through Monte Carlo simulations. Overall, the highest SFR was associated with G. stearothermophilus (380000 bottles contaminated in 10(11) bottles produced) and the lowest to C. botulinum (3 bottles contaminated in 10(11) bottles produced). Unsurprisingly, SFR due to G. stearothermophilus was due to its ability to survive the UHT treatment. More interestingly, it was identified that SFR due to B. cereus (17000 bottles contaminated in 10(11) bottles produced) was due to an airborne recontamination of the aseptic tank (49%) and a post-sterilisation packaging contamination (33%). A deeper analysis (sensitivity and scenario analyses) was done to investigate how the SFR due to B. cereus could be reduced by changing the process settings related to potential air recontamination source.


Assuntos
Fenômenos Fisiológicos Bacterianos , Microbiologia de Alimentos , Embalagem de Alimentos/normas , Modelos Teóricos , Animais , Bacillus cereus/fisiologia , Clostridium botulinum/fisiologia , Geobacillus stearothermophilus/fisiologia , Leite/microbiologia , Esterilização/normas
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