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Abstract: Marine protected areas (MPAs) are increasingly envisaged as a tool to manage coastal ecosystems and fisheries. Assessment of their performance with respect to management objectives is therefore important. A number of MPAs provided conservation benefits for fished species. Observed benefits do not apply to all species at all times, and responses to protection are also highly variable among fish taxa. Among the many empirical studies on marine reserves, only a few designs considered ‘before and after data’ and spatial variation. In this paper, we are interested in assessing the effect of a no-take reserve on the reef fish assemblage in a northwestern Mediterranean example. Data were obtained from a three-year survey using underwater visual censuses (UVC), before and after MPA establishment. Permutational multivariate analysis of variance (PERMANOVA) and multivariate regression trees (MRT) were used to evaluate the effects of reserve protection on the reef fish assemblage, while accounting for habitat. Modelled biological responses were abundances and diversity indices calculated at different levels of the assemblage. Significant effects were found for many of these metrics. In addition to PERMANOVA, univariate models provided more insight into the magnitude and direction of effects. The most sensitive metrics were related to large species and species targeted by fishing. These results may be used to choose the metrics that are more suitable as community-based indicators of MPA impact in the perspective of monitoring programs. [Copyright &y& Elsevier]

OBJECTIVE: To determine the effectiveness of using citizen politics as a framework for empowering citizens to build a community food security agenda. DESIGN: A critical perspective, case study design, and multiple qualitative methods were used. Participants/Setting: Forty-four participants were purposefully recruited to participate in a community-based planning process called a search conference (SC). Seven additional disenfranchised stakeholders who did not attend the SC were also recruited to participate. Phenomenon of Interest: To assess how power influenced agenda setting and to determine the extent to which disenfranchised stakeholders' most salient interests were incorporated into the final SC action agendas. ANALYSIS: The constant comparison method, content analysis, and consensus were used to produce the final analysis. RESULTS: Power influenced agenda setting by managing knowledge, problem framing, trust, and consent. Two of seven of disenfranchised stakeholders' most salient interests, including need for adequate food preparation skills and increased availability of locally produced foods, were incorporated into the final SC action agendas. CONCLUSIONS AND IMPLICATIONS: Citizen politics can be used to build a community food security agenda on issues that are not at odds with stakeholders in positions of power. To bring about change on issues in which power differences between groups are substantial, additional theoretical frameworks and public policy-making models are needed. [ABSTRACT FROM AUTHOR]

An accurate measurement of the transverse relaxation time T2, and the histogram of T2 in the brain parenchyma can be accomplished in vivo using a multi-echo magnetic resonance imaging sequence. An estimate of the error in the T2 measurement is derived using copper sulfate doped water phantoms. Correction factors are calculated and applied to the signal intensity of each voxel prior to the in vivo T2 evaluation. These corrected T2 are in good agreement with the theoretical values calculated from copper sulfate concentrations. This technique is then applied to calculate T2 histograms of the brain. The population studied was composed of normal volunteers and multiple sclerosis patients. The corrected T2 histogram method discriminates the normal control population from the MS population, and also discriminates between relapsing-remitting patients and primary progressive or secondary progressive patients. Moreover using this approach we are able to detect in MS patients a global shift of the T2 of the white mater toward higher values. The results of this study showed that the method is easy to implement and may be used to characterize MS pathology. [Copyright &y& Elsevier]

To determine if metabolite ratios as measured by 3-dimensional echo planar spectroscopy imaging (3D-EPSI) from central brain regions of interest (ROI) centered at the corpus callosum reflect imaging metrics of large volumes of supratentorial brain (STB) from patients with multiple sclerosis. Methods: 48 MS patients with relapsing-remitting, secondary progressive, and primary progressive disease underwent a 3D-EPSI sequence covering large volumes of STB. Metabolite ratios were first estimated from all voxels within a STB mask using a linear regression of N-acetylaspartate (NAA) over Creatine (Cr), NAA over choline (Cho) and Cho over Cr. Secondly, spectroscopic voxels from a central brain (CB) ROI centered at the corpus callosum were selected within the STB. Ratios were compared using Bland-Altman regression analysis and Spearman’s correlation coefficients between STB versus central brain. Ratios from studied ROIs were correlated with the EDSS and compared to normal controls. Results: Very strong correlations ranging from 0.884 and 0.938 (p < 0.0001) were found for all metabolite ratios between STB versus central brain. NAA/Cr ratios were similarly and negatively correlated with the EDSS across all ROIs, trends ranging from −0.257 to −0.314 (p < 0.1). NAA/Cr from all MS patients was similarly decreased compared to controls across all ROIs (p < 0.01). Conclusion: Metabolite ratios from a central brain ROI were statistically equivalent and highly correlated with ratios from the STB. The study of NAA/Cr using 1HMRS from a central brain ROI centered at the corpus callosum seems to be representative of brainwide axonal changes in patients with MS. [Copyright &y& Elsevier]

This paper presents adaptive finite element computations of laminar jet impingement heat transfer. Variable fluid properties and compressibility effects are considered. A unified formulation of the equations is used to treat the simultaneous presence of three flow regimes: incompressible (ρ=constant), compressible (ρ=ρ(p,T)), and anelastic (ρ=ρ(T)). The error estimator uses a local least squares projection method and accounts for errors in velocity, pressure and temperature. The performance of the methodology is verified by solving a problem possessing a closed form solution. Several applications are then considered. We study two different gases (air and CO2), different conditions (heated, cooled or constant properties), compressibility and inlet velocity profile effects. Heat transfer is a key element of the study. Results indicate that the methodology can produce grid independent solutions even for derived quantities and in thin boundary layers. [Copyright &y& Elsevier]

The relationship of anemia as a risk factor for maternal mortality was analyzed by using cross-sectional, longitudinal and case-control studies because randomized trials were not available for analysis. The following six methods of estimation of mortality risk were adopted: 1) the correlation of maternal mortality rates with maternal anemia prevalence derived from national statistics; 2) the proportion of maternal deaths attributable to anemia; 3) the proportion of anemic women who die; 4) population-attributable risk of maternal mortality due to anemia; 5) adolescence as a risk factor for anemia-related mortality; and 6) causes of anemia associated with maternal mortality. The average estimates for all-cause anemia attributable mortality (both direct and indirect) were 6.37, 7.26 and 3.0% for Africa, Asia and Latin America, respectively. Case fatality rates, mainly for hospital studies, varied from <1% to >50%. The relative risk of mortality associated with moderate anemia (hemoglobin 40-80 g/L) was 1.35 [95% confidence interval (CI): 0.92-2.00] and for severe anemia (<47 g/L) was 3.51 (95% CI: 2.05-6.00). Population-attributable risk estimates can be defended on the basis of the strong association between severe anemia and maternal mortality but not for mild or moderate anemia. In holoendemic malarious areas with a 5% severe anemia prevalence (hemoglobin <70 g/L), it was estimated that in primigravidae, there would be 9 severe-malaria anemia-related deaths and 41 nonmalarial anemia-related deaths (mostly nutritional) per 100,000 live births. The iron deficiency component of these is unknown. [ABSTRACT FROM AUTHOR]

The prevention of child mortality is a commonly stated health goal in developing countries and the target of much international assistance in the health sector. Over the past decade the primary strategy for accelerating the reduction in child mortality has been the dissemination of simple, low-cost technologies, such as immunization, oral rehydration therapy and antibiotics, that target specific diseases (Huffmann and Steel 1994). This is done despite the knowledge that malnutrition and. disease have a synergistic relationship (Scrimshaw et al. 1968) and that the optimal strategy may involve a combination of health and nutrition interventions. In the 1970s, for instance, it was estimated that malnutrition (notably protein-energy malnutrition—PEM) was the underlying or contributing cause of death for roughly half of all deaths to children aged 1–4 years in several Latin American countries (Puffer and Serrano 1973). Apart from this early study, however, there has been little effort to quantify the contribution of malnutrition to child mortality in other regions of the in ways which are meaningful to policy. This paper reviews the results of 28 community-based, prospective studies, in 12 Asian and Sub-Saharan African countries, which examined the relationship between anthropometric indicators of malnutrition and child mortality. One purpose is to estimate the contribution of malnutrition to child mortality—distinguishing the effects of severe malnutrition from mild-to-moderate malnutrition— and to examine a number of related issues relevant to policy, programs and research in this are. The accumulated results are consistent in showing that the risk of mortality is inversely related to anthropometric indicators of nutritional status and that there is elevated risk even in the mild-to-moderate range of malnutrition. This latter result contradicts the findings from an earlier, landmark study which suggested that mild-to-moderate malnutrition was not associated with an increased risk of mortality (Chen et al. 1980). The present results indicate that somewhere between 20% and 75% of child deaths are statistically attributable to anthropometric deficits, with most estimates falling in the range 25–50%. When taking account of the relative proportions of severe versus mild-to-moderate malnutrition in the population, the results show further than 16–80% of all nutrition-related deaths are associated with mild-to-moderate malnutrition rather than severe malnutrition. In most studies 46–80% of all nutrition-related deaths are in the mild-to-moderate category. This represents the proportion of nutrition-related deaths that would be missed by policies and programs focusing primarily or exclusively on the severely malnourished, a bias that does exist in many public health programs in practice if not by design. Another important result is the confirmation that malnutrition has a potentiating (multiplicative) effect on mortality within populations, as predicted from the theory of synergism. This means that malnutrition has its biggest impacts in populations with already high mortality levels and that morbidity has its biggest impacts in the most malnourished populations. This finding has far-reaching implications for child survival policy and programs, suggesting that greater attention should be paid to nutritional improvement than at present. A potential limitation of the above conclusion is the possibility that the relationship between mortality and malnutrition may be confounded by behavioral and socioeconomic factors (e.g., caretaker knowledge and practices and access to health care).… [ABSTRACT FROM AUTHOR]

As shown in a review of 28 studies, anthropometric measurements of preschool-aged children are consistently related to the risk of subsequent mortality in community-based studies from Asia and Africa (Pelletier 1994). Although the results are consistent at this general level, a number of important questions remain concerning the relationship. The purpose of this study is to address two of these questions using data from a similar study conducted in rural northern Malawi. 1) In relation to screening, are the anthropometry-mortality relationships affected by the child's age and the interval between measurement and death (‘length of follow-up’) and 2) In relation to policy implications, is the anthropometry-mortality relationship due to confounding by socioeconomic factors, especially when considering mild-to-moderate malnutrition. The results reveal that mortality prediction is significantly affected by child's age and length of follow-up, but the strength and direction of this effect modification varies across the four commonly used anthropometric indicators [weight-for-age (WA), height-for-age (HA), weight-for-height (WH) and arm circumference-for-age (ACA)]. An important result for public health practice is that there are no statistically significant differences in prediction across these four indicators when applied to young children (6–23 mo) and employing a 1-y follow-up period. As regards confounding, the results indicate that the anthropometry-mortality relationship is not due to confounding by socioeconomic factors when all grades of malnutrition are considered. When only mild-to-moderate malnutrition is considered, statistically controlling for confounders reduces most of the anthropometric predictors to nonsignificance (probability values to >0.20), but the strength of the association (odds ratio) remains of the same order of magnitude. However, when effect modification by child's age and length of follow-up is taken into account, the effect of mild-to-moderate malnutrition (WA and WH) remains statistically significant for young children dying within 1 y of follow-up. [ABSTRACT FROM AUTHOR]

There are five broad categories of food-related public health problems in the U.S. for which survey data on food consumption are needed. These relate to reproduction, growth and development, chronic disease, food safety, food insecurity and problems specific to the elderly. The collection and analysis of food consumption data has become increasingly difficult for three major reasons. First, broad societal trends (e.g., ethnicity and use of food away from home) and changes in the food production, processing and marketing sectors have complicated the task. Second, the traditional concerns of monitoring (tracking population means and prevalences) are no longer the only objectives; there is a growing demand for data on habitual intake of individuals and variability in habitual intakes (e.g., to estimate the frequency of acute exposures). Third, data are required at several levels of aggregation (e.g., nutrients, food categories, commodities and name-brand foods) and a high frequency of non-consumption at lower levels of aggregation places high demands on sample size. It is suggested that the current large national surveys be supplemented with special purpose surveys that meet individual agency needs, and that principles and methods of state and local monitoring be further developed and implemented. [ABSTRACT FROM AUTHOR]

The objective of the present paper is to study the ability of an order of magnitude analysis (Garandet et al., 2012) [1] to give a realistic picture of segregation patterns in vertical Bridgman configurations, on the basis of hydrodynamic simulations. The scaling analysis leads to an analytical formulation of the solute boundary layer, involving the wall-shear stress at the solid/liquid interface. In order to test this analytical model, transient simulations of solute segregation in a 2D lid driven cavity configuration have been performed. The developed analytical model, which involves a quasi-steady approximation, is in good agreement with the numerical time-dependent results. The key results of this work are the correlation of segregation patterns in the solid with flow patterns in the liquid and the ability of the analytical model to describe lateral segregations and to capture unsteadiness in the limit of slow variations associated with Bridgman configurations. [ABSTRACT FROM AUTHOR]

Abstract: The effect of lid driven convective flows on lateral solute segregation in the vicinity of a crucible wall is studied in an idealized 2D melt crystal growth configuration. An order of magnitude analysis of the transport equation is performed, with the objective of identifying scaling laws between the relevant physical parameters of the problem. Numerical simulations are also carried out using the commercial software Fluent. Control variables, apart from the species molecular diffusion coefficient, are the lid and solidification velocities. The simulation results are in fair agreement with the predictions of the theoretical approach. Overall, the data show that very strong convective levels are necessary to keep lateral segregation within reasonable limits. [Copyright &y& Elsevier]

Abstract: This paper presents manufactured solutions (MS) for verification of a fluid-structure interactions code. MS provide benchmark solutions for direct evaluation of the solution errors. The method of manufactured solutions (MMS) is a straight forward and general procedure for generating exact analytical solutions with a sufficiently rich structure to ensure that all terms of the differential equations are exercised in the simulations. When used with systematic grid refinement studies, the MMS provides strong code verification with a theorem-like quality. Manufactured solutions for fluid-structure interaction (FSI) problems with large displacements are presented with sample results from grid convergence studies. [Copyright &y& Elsevier]

Changes in biodiversity may disrupt the ecological functions performed by species assemblages. Hence, we urgently need to examine the implications of biodiversity loss not only in terms of species conservation but also in terms of sustainability of ecosystem services. The ability of protected areas to maintain local species richness has been clearly demonstrated. However, preserving goods and services provided by ecosystems requires not only the conservation of species richness but also the conservation of the most ‘original’ species, i.e. the ones with the highest average rarity of their attributes which are likely to perform some unique functions in ecosystems. We proposed a new conservation of biological originality (CBO) index as well as associated randomization tests to quantify the ability of protected areas to maintain viable populations for the most original species. As an application, we used long-term fisheries data collected in the Bonifacio Strait Natural Reserve (BSNR) to determine the species which benefited from the protection reinforcement in 1999. We also estimated a set of 14 ecomorphological functional traits on the 37 fish species caught in the BSNR and we obtained a functional originality value for each species. As a result, we found that functional originality was significantly protected in the fish assemblage of the BSNR: species with the most original functional trait combinations became more abundant after 1999. Our finding suggests that protecting most original species is an insurance against functional diversity erosion in the BSNR. More generally, our new index can be used to test whether protected areas may protect preferentially the most original species and whether restorative management promotes the reestablishment of the most original species with particular habitat requirements. [Copyright &y& Elsevier]

Abstract: This paper presents a continuous sensitivity equation method (SEM) for incompressible turbulent heat transfer. The k–ɛ model of turbulence with wall functions is used to model turbulence. Heat transfer is handled using an eddy conductivity. The SEM formulation accounts for complex parameter dependence and is suitable for a wide range of problems. It is applied to turbulent flow over a heated backward facing step and to turbulent flow over a heated flat plate. Several uses of the SEM are demonstrated: fast computation of nearby flows, identification of key parameters controlling the flow, and uncertainty analysis. Sensitivities are used to cascade input data uncertainties through the CFD code to yield uncertainty estimates of the skin friction and Stanton number. The SEM also provides detailed information about the contribution of each parameter to the global uncertainty. [Copyright &y& Elsevier]

Various upgrades of the Czochralski (Cz) growth process are currently being investigated in order to increase throughput and reduce production cost of high efficiency silicon-based solar cells. However, as-grown thermal donors (TD) in Cz silicon can significantly reduce the conversion efficiency of such solar cells. An accurate simulation tool is therefore required to investigate and optimize TD formation during crystal growth. A numerical method combining thermo-hydraulic simulations and a kinetic TD formation model was improved by the implementation of a more appropriate TD formation model, identified through a benchmark of the different models available in the literature. Three different Cz growth processes were investigated both numerically and experimentally. Numerical results are in remarkable agreement with TD concentrations measured along the three ingots by the OxyMap technique developed at CEA. The simulations were then used to detect when TD were formed during Cz processes. The reliability of the method was also assessed through sensitivity analyses, highlighting the critical importance of the input interstitial oxygen concentration. These results show that accurate estimates of axial TD concentration profiles can be obtained and so for very different Cz processes, supporting the robustness of the developed method and its relevance to process optimization and furnace design to reduce TD concentrations. • A numerical method for thermal donors (TD) formation during Cz growth was improved. • Four thermal donors formation models proposed in the literature were benchmarked. • Three Cz processes were investigated both numerically and experimentally. • Simulations were used to detect when TD were formed (ingot growth or cooling). • The method is highly sensitive to the interstitial oxygen concentration input value. [ABSTRACT FROM AUTHOR]

The present paper focuses on directional solidification processes for photovoltaic silicon purification. The use of a mechanical stirrer in the melt to enhance impurity segregation is investigated through numerical simulations. The 3D forced convection flow is resolved in a transient regime thanks to a sliding mesh approach. The hydrodynamic model is coupled to a solute transport simulation in a quasi-steady approximation (i.e. with constant liquid height). Velocity measurements are performed by Particle Image Velocimetry on a water model in order to validate hydrodynamic simulations. Numerical results show that an efficient segregation can be achieved, even for high solidification rates, thanks to mechanical stirring. The numerical model provides meaningful insights for process optimization as it correlates the impurity repartition on the solidification front to the stirring parameters. Finally, the numerical segregation results are compared to an analytical model of the solute boundary layer. It is found that the analytical model provides a good estimate of the mean segregation regime from an hydrodynamic simulation of the forced convection flow, which makes it a useful tool for process design. [ABSTRACT FROM AUTHOR]

Abstract: This study focuses on the parameterization of a model describing the dynamics of an exploited population and aims at improving management practices by simulating various measures. The study species is white seabream, an important resource exploited by the mixed fisheries of the French Catalan coast, where the Cerbère-Banyuls marine reserve was created more than 30 years ago. We used the ISIS-Fish fishery simulation model to evaluate the population''s sustainability under the current fishing regime. This simulator combines three sub-models within a single working environment: population dynamics, multi-fleet exploitation and management measures. Knowledge of the white seabream and related fishing activities was compiled from both literature and analyses of existing fisheries data, and is used to parameterize and calibrate the model. Simulation results highlighted that: (i) under current management, the white seabream population biomass has declined to 88% of initial biomass over 20 years; (ii) with various scenarios of recruitment, the population dynamics tends to stabilize over the long term. In a second article (), we undertook an analysis of the sensitivity of the model to uncertain parameters and explored scenarios aiming at evaluating the impact of fishing activities and the effects of protection effects on white seabream dynamics. [Copyright &y& Elsevier]

Abstract: In this paper, the ISIS-fish model was used to assess the impact of spatial and seasonal management measures on the dynamics of the white seabream population (Diplodus sargus sargus) in the French Catalan fishery (north-western Mediterranean). This work is the second part of a paper () which describes the parameterization of the model. Here we carry out a sensitivity analysis to identify the most significant model parameters. The simulation results show that the model is particularly sensitive to some parameters such as natural mortality, stage length, fecundity, number of inactive days per strategy and gear standardisation factors. Second, the impact of several management measures was evaluated (e.g. marine protected areas (MPAs) in the nursery and spawning zones, changes in gillnet mesh size and fishing effort reduction). Management scenarios were then assessed and compared using a simulation design. The results indicate that the permanent closures in the white seabream juvenile habitat for all gears, a change in gillnet mesh size and fishing effort reduction would result in an important increase in the population biomass and catch. The closures of the spawning zones appear inefficient in restoring D. sargus biomass. [Copyright &y& Elsevier]

Abstract: The use of scuba-based photo/video methods for characterizing coral reef habitats has gained increased popularity within the last decade, but few work examined the potentiality of surface photography to provide accurate, reliable habitat profiles in contrasted habitats. Photo transects were thus conducted by snorkeling in contrasted reef biotopes (reef flat, reef crest, sandy bottom) from the south-west lagoon of New Caledonia, to develop and test a “quick and clean” approach suitable for addressing monitoring as well as research-oriented programs. Pictures were taken by a snorkeler from the surface over twelve (20×1 m) reef crest/reef flat/soft bottoms transects using a standard 8 Mpixel digital-camera with underwater housing. Habitats were characterized from percent covers for 15 categories of local habitat variables related to sediment type and substrate coverage. Exhaustive area analyses using computer-assisted manual digitalizing were used to provide reliable habitat profiles from the digital pictures. Results were subsequently compared with surface estimates derived from random stratified point count techniques, for numbers of points comprised between 1 and 99 per m2. Sampling-based randomization techniques allowed us to provide robust, reliable statistical estimates of accuracy and precision over 1000 randomized bootstrap replicates per transect. Results emphasized high accuracy and precision at transect scale whatever the reef biotopes considered, with maximum deviations from reference values of ∼1 percent cover in almost all cases and associated variances <0.001. From a practical point of view, using a 9 points/m2 ratio clearly provided reliable, quantitative descriptions of our reef transects (maximal errors <1.5 percent cover with 95% confidence level). Cost-effectiveness is high, with 15-30 minutes/transect from field data collection (<10 min) to computation of final percent covers (10-20 min). The method outlined in this paper thus combines high statistical efficiency and logistical ease, and could be used to address more functional perspectives. [Copyright &y& Elsevier]

Student teaching, the most important stage of a teacher candidate's preparation, was profoundly affected by the COVID-19 pandemic. For world language (WL) student teachers, the effects were even more pronounced, as language learning and teaching were given an even lower priority than usual. In this study we use collaborative, co-constructed autoethnographic narratives to explore how five participant researchers experienced the sudden shift to emergency remote learning during the beginning stages of the pandemic. Findings indicate an overall feeling of disconnect from classroom practices and district communication, followed by disparate student teaching experiences depending upon the districts' socioeconomic makeup. Other findings corroborate previous research demonstrating decreased student engagement and diminished attention to world language as a content area by both districts and families. However, we also believe that our experiences during the pandemic allowed us to acquire important skills in online teaching and caring for students, which we plan to utilize in our future careers. Within the context of these findings, we offer suggestions for future emergency remote teaching situations in the context of WL teacher education. [ABSTRACT FROM AUTHOR]

Abstract: Overexploitation of marine resources remains a problem worldwide. Many works advocate for the use of marine reserves as a central element of future stock management in a sustainable perspective. In the present paper, we address the influence of protected areas upon fisheries sustainability within an eco-systemic framework through a dynamic bio-economic model integrating a trophic web, catches and environmental uncertainties. The model is spatially implicit. The evaluation of the ecosystem is designed through the respect along time of constraints of both conservation and guaranteed captures. Using the mathematical concept of invariance kernel in a stochastic context, we define different MPA effects according to biodiversity, catches or mixed points of view. Numerical simulations inspired from data of Aboré coral reef reserve in New Caledonia illustrate the main concepts. In this case, it is pointed out how MPA conservation effect is not necessarily conflicting with MPA catches effect. It is shown that such a co-viability requires medium exploitation rate. Moreover, the climatic changes represented by rise in cyclonic events seem to reinforce these assertions. [Copyright &y& Elsevier]