13 research outputs found

    iCollections – Digitising the British and Irish Butterflies in the Natural History Museum, London

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    This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article.NHM Repositor

    Continuum-based models and concepts for the transport of nanoparticles in saturated porous media: A state-of-the-science review

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    Environmental applications of nanoparticles (NP) increasingly result in widespread NP distribution within porous media where they are subject to various concurrent transport mechanisms including irreversible deposition, attachment/detachment (equilibrium or kinetic), agglomeration, physical straining, site-blocking, ripening, and size exclusion. Fundamental research in NP transport is typically conducted at small scale, and theoretical mechanistic modeling of particle transport in porous media faces challenges when considering the simultaneous effects of transport mechanisms. Continuum modeling approaches, in contrast, are scalable across various scales ranging from column experiments to aquifer. They have also been able to successfully describe the simultaneous occurrence of various transport mechanisms of NP in porous media such as blocking/straining or agglomeration/deposition/detachment. However, the diversity of model equations developed by different authors and the lack of effective approaches for their validation present obstacles to the successful robust application of these models for describing or predicting NP transport phenomena. This review aims to describe consistently all the important NP transport mechanisms along with their representative mathematical continuum models as found in the current scientific literature. Detailed characterizations of each transport phenomenon in regards to their manifestation in the column experiment outcomes, i.e., breakthrough curve (BTC) and residual concentration profile (RCP), are presented to facilitate future interpretations of BTCs and RCPs. The review highlights two NP transport mechanisms, agglomeration and size exclusion, which are potentially of great importance in controlling the fate and transport of NP in the subsurface media yet have been widely neglected in many existing modeling studies. A critical limitation of the continuum modeling approach is the number of parameters used upon application to larger scales and when a series of transport mechanisms are involved. We investigate the use of simplifying assumptions, such as the equilibrium assumption, in modeling the attachment/detachment mechanisms within a continuum modelling framework. While acknowledging criticisms about the use of this assumption for NP deposition on a mechanistic (process) basis, we found that its use as a description of dynamic deposition behavior in a continuum model yields broadly similar results to those arising from a kinetic model. Furthermore, we show that in two dimensional (2-D) continuum models the modeling efficiency based on the Akaike information criterion (AIC) is enhanced for equilibrium vs kinetic with no significant reduction in model performance. This is because fewer parameters are needed for the equilibrium model compared to the kinetic model. Two major transport regimes are identified in the transport of NP within porous media. The first regime is characterized by higher particle-surface attachment affinity than particle-particle attachment affinity, and operative transport mechanisms of physicochemical filtration, blocking, and physical retention. The second regime is characterized by the domination of particle-particle attachment tendency over particle-surface affinity. In this regime although physicochemical filtration as well as straining may still be operative, ripening is predominant together with agglomeration and further subsequent retention. In both regimes careful assessment of NP fate and transport is necessary since certain combinations of concurrent transport phenomena leading to large migration distances are possible in either case

    Fatores de risco para perda ponderal de crianças frequentadoras de berçários em creches do município de São Paulo Risk factors for ponderal loss of children attending the nurseries of day care centers in São Paulo, Brazil

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    OBJETIVO: Identificar e quantificar os fatores de risco relacionados ao agravamento da condição nutricional entre o nascimento e a realização deste estudo. MÉTODOS: Estudo transversal com 270 crianças frequentadoras dos berçários de oito creches públicas e filantrópicas do município de São Paulo. Considerou-se com perda ponderal as crianças que apresentaram diferença negativa do escore Z para a relação peso para idade entre o nascimento e a ocasião da realização desse inquérito. No estudo das associações, utilizou-se o teste do qui-quadrado e consideraram-se as variáveis com nível de significância p<0,05. Foi ajustado modelo multivariado de regressão logística com estimativas de razões de chance (Odds Ratio, OR) para o controle de covariáveis ou variáveis de confundimento. RESULTADOS: A análise antropométrica revelou prevalência de desnutrição (P/I <-2 escore Z) de 7,1% no nascimento e de 4,4% na ocasião da medida e evidenciou evolução ponderal em escore Z desfavorável para 50,7% das crianças (n=137). Nas análises bivariadas, as variáveis "peso de nascimento suficiente" (OR=5,35; p<0,001), "anemia" (OR=1,81; p=0,019) e "idade menor que 19 meses" (OR=1,67; p=0,036) alcançaram significância estatística. CONCLUSÕES: A perda ponderal em escore Z ao longo dos primeiros meses de vida é um indicador ainda pouco utilizado em estudos epidemiológicos, mas a realização de outras pesquisas poderá identificá-la como um indicador de risco de vulnerabilidade sociobiológica. Sugere-se a execução de programas de Saúde voltados ao controle da perda ponderal e que enfoquem a população infantil de menor idade e/ou com anemia, de modo a reduzir a prevalência dos agravos nutricionais.<br>OBJECTIVE: To identify and quantify risk factors related to the aggravation of nutritional condition from birth until the date of the study. METHODS: Cross-sectional study with 270 children attending nurseries of eight public and non-for-profit daycare centers in the city of São Paulo, Brazil. Ponderal loss was considered when children presented negative difference of Z score for weight-for-age (W/A) from birth until the date of the present inquiry. Chi-square was used to test associations and considered significant if p<0.05. Multivariate logistic regression model adjusted Odds Ratio estimates for confounding variables and/or covariables. RESULTS: Anthropometric analysis showed 7.1% prevalence of malnutrition (W/A<-2 Z score) at birth and 4.4% by the time of measurement. Ponderal evolution with unfavorable Z score was present in 50.7% of studied children (n=137). In the bivariate analyses, the variables: birth weight (OR=5.35; p<0.001), anemia (OR=1.81; p=0.019) and age less than 19 months (OR=1.67; p=0.036) were statistically significant. CONCLUSIONS: Ponderal loss in Z score during the first months of life has not been often used in epidemiological studies. However, future researches might identify weight loss as an indicator of risk for sociobiological vulnerability. Development of health programs in order to reduce the prevalence of nutritional aggravation targeting the younger population with anemia is strongly recommended

    Marat-Sade - La persecuzione e l'assassinio di Jean Paul Marat rappresentati dai ricoverati del manicomio di Charenton sotto la guida del marchese di Sade, di Peter Weiss. Con l'esecuzione dal vivo de "Il cimento dell'armonia e dell'inventione. Opera VIII - Le quattro stagioni" di Antonio Vivaldi eseguita dall'Ensemble Europa Galante diretto da Fabio Biondi.

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    Incidental music Marat-Sade, nell\u2019unica traduzione italiana di Ippolito Pizzetti, con musica dal vivo. In questo progetto-evento, Walter Le Moli ha innestato uno dei capolavori della drammaturgia del Novecento sulla immortale partitura vivaldiana, dando cos\uec una funzione di primaria importanza drammatica non solo alla musica, ma alla presenza dell\u2019Orchestra in palcoscenico. Un cast di oltre quaranta attori e musicisti d\ue0 vita ad una asettica ma folgorante rappresentazione di una realt\ue0 che, come cita lo stesso autore in una nota al testo, vuole gettare una luce sul \u201cconfronto tra Marat e Sade come conflitto dell\u2019individualismo portato alle estreme conseguenze e idea della rivoluzione politica e sociale\u201d. La produzione nasce sotto l\u2019egida della collaborazione tra il Teatro di Roma, il Teatro Stabile di Torino e la Fondazione Teatro Due di Parma. Prima nazionale al Teatro Argentina di Roma l'11 gennaio 2005 - in anteprima al Teatro Due di Parma il 4 e 5 gennaio - e riproposto a Torino, Ex Fonderie Limone, nel luglio del 2005
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