1,463 research outputs found

    Food Security Status and Barriers to Fruit and Vegetable Consumption in Two Economically Deprived Communities of Oakland, California, 2013-2014.

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    IntroductionFood security status may moderate how people perceive barriers to fruit and vegetable consumption. This study aimed to 1) describe the association between fruit and vegetable consumption and microbarriers and mezzobarriers to consumption, and 2) test whether these associations differ by food security status.MethodsWe surveyed adults (n = 531) living in 2 economically deprived communities in Oakland, California, in 2013 and 2014. Multivariate linear regression assessed associations between microbarriers (taste, cost, busyness) and mezzobarriers (produce selection, quality, and purchase ease) and fruit and vegetable consumption, derived from a 26-item dietary screener. Interactions were tested by food security status.ResultsRespondents consumed a mean 2.4 (standard deviation, 1.5) servings of fruits and vegetables daily; 39% of the sample was food insecure. Being too busy to prepare healthy foods was associated with reduced fruit and vegetable consumption (ÎČ(busyness) = -0.40; 95% confidence interval [CI], -0.52 to -0.28) among all respondents. Food security moderated the relationship between fruit and vegetable consumption and taste, cost, and perceived ease of purchase of healthy foods. Among the food secure, disliking healthy food taste (ÎČ(taste) = -0.38; 95% CI, -0.60 to -0.15) and cost (ÎČ(cost) = -0.29; 95% CI, -0.44 to -0.15) concerns were associated with lower consumptions of fruits and vegetables. Mezzobarriers were not significantly associated with consumption in either group.ConclusionPerceived time constraints influenced fruit and vegetable consumption. Taste and cost influenced fruit and vegetable consumption among the food secure and may need to be considered when interpreting analyses that describe dietary intake and designing diet-related interventions

    A study of the hydrographic conditions in the Adriatic Sea from numerical modelling and direct observations (2000–2008)

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    The inter-annual variability of Adriatic Sea hydrographic characteristics is investigated by means of numerical simulation and direct observation. The period under investigation runs from the beginning of 2000 to the end of 2008. The model used to carry out the simulation is derived from the primitive equation component of the Adriatic Forecasting System (AFS). The model is based on the Princeton Ocean Model (POM) adapted in order to reproduce the features of the Adriatic. Both numerical findings and observations agree in depicting a strong inter-annual variability in the entire Adriatic Sea and its sub-basins. Nevertheless, two model deficiencies are identified: an excessive vertical/horizontal mixing and an inaccurate representation of the thermohaline properties of the entering Mediterranean Waters. The dense water formation process has been found to be intermittent. In addition to inter-annual variability, a long-scale signal has been observed in the salinity content of the basin as a consequence of a prolonged period of reduced Po river runoff and high evaporation rates. As a result, the temperature and salinity of the northern Adriatic dense water vary considerably between the beginning and the end of the period investigated

    Long-term physical evolution of an elastomeric ultrasound contrast microbubble

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    Hypothesis: One of the main assets of crosslinked polymer-shelled microbubbles (MBs) as ultrasound-active theranostic agents is the robustness of the shells, combined with the chemical versatility in modifying the surface with ligands and/or drugs. Despite the long shelf-life, subtle modifications occur in the MB shells involving shifts in acoustic, mechanical and structural properties. Experiments: We carried out a long-term morphological and acoustic evolution analysis on elastomeric polyvinyl-alcohol (PVA)-shelled MBs, a novel platform accomplishing good acoustic and surface performances in one agent. Confocal laser scanning microscopy, acoustic spectroscopy and AFM nanomechanics were integrated to understand the mechanism of PVA MBs ageing. The changes in the MB acoustic properties were framed in terms of shell thickness and viscoelasticity using a linearised oscillation theory, and compared to MB morphology and to nanomechanical analysis. Findings: We enlightened a novel, intriguing ageing time evolution of the PVA MBs with double behaviour with respect to a crossover time of ∌50 days. Before, significant changes occur in MB stiffness and shell thickness, mainly due to a massive release of entangled PVA chains. Then, the MB resonance frequency increases together with shell thickening and softening. Our benchmark study is of general interest for emerging viscoelastomeric bubbles towards personalised medicine

    Physio-morphological traits and drought stress responses in three wild Mediterranean taxa of Brassicaceae

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    Crop wild relatives (CWRs) have extremely relevant roles in biodiversity conservation, in investigating phylogeny and improving abiotic stress tolerance of crop plants. We screened the variability in leaf functional traits of three CWRs of kale crops (Brassica oleracea) from Sicily, Italy, grown in pots under well-watered and drought conditions. Our aim was to highlight traits in the different genotypes of endemic Sicilian threatened taxa. We measured several structural/anatomical traits (stomatal size, density and stomatal pore index—SPI, leaf mass per area—LMA) and leaf functional traits (stomatal conductance—gs, leaf water potential—ιL, leaf temperature (TL), leaf relative water content—RWC) at pre-dawn and midday of leaves of three wild taxa: B. macrocarpa, B. rupestris subsp. rupestris and B. villosa subsp. bivoniana. Pressure–volume curves were constructed to obtain leaf water potential at turgor loss point (Κtlp), osmotic potential at full rehydration (Κπ100), relative water content at turgor loss point (RWCtlp), elastic bulk modulus (Δmax) and leaf area specific capacitance at full turgor (Cft*). Several significant differences were found among the taxa: under water deficit, B. macrocarpa had the less negative Κtlp and showed the smallest ΔιL between pre-dawn and midday. B. villosa subsp. bivoniana showed the highest SPI and had significantly higher gs under water availability, while under drought it had the most negative ΚL. Each of the taxa investigated possessed traits that confer particular stress tolerance, offer competitive advantage in their natural environment and may be exploited for crop improvement

    sensitivity of the mediterranean sea level to atmospheric pressure and free surface elevation numerical formulation in nemo

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    Abstract. The sensitivity of the dynamics of the Mediterranean Sea to atmospheric pressure and free surface elevation formulation using NEMO (Nucleus for European Modelling of the Ocean) was evaluated. Four different experiments were carried out in the Mediterranean Sea using filtered or explicit free surface numerical schemes and accounting for the effect of atmospheric pressure in addition to wind and buoyancy fluxes. Model results were evaluated by coherency and power spectrum analysis with tide gauge data. We found that atmospheric pressure plays an important role for periods shorter than 100 days. The free surface formulation is important to obtain the correct ocean response for periods shorter than 30 days. At frequencies higher than 15 days−1 the Mediterranean basin's response to atmospheric pressure was not coherent and the performance of the model strongly depended on the specific area considered. A large-amplitude seasonal oscillation observed in the experiments using a filtered free surface was not evident in the corresponding explicit free surface formulation case, which was due to a phase shift between mass fluxes in the Gibraltar Strait and at the surface. The configuration with time splitting and atmospheric pressure always performed best; the differences were enhanced at very high frequencies

    Numerical simulation and decomposition of kinetic energy in the Central Mediterranean: insight on mesoscale circulation and energy conversion

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    The spatial and temporal variability of eddy and mean kinetic energy of the Central Mediterranean region has been investigated, from January 2008 to December 2010, by mean of a numerical simulation mainly to quantify the mesoscale dynamics and their relationships with physical forcing. In order to understand the energy redistribution processes, the baroclinic energy conversion has been analysed, suggesting hypotheses about the drivers of the mesoscale activity in this area. The ocean model used is based on the Princeton Ocean Model implemented at 1/32° horizontal resolution. Surface momentum and buoyancy fluxes are interactively computed by mean of standard bulk formulae using predicted model Sea Surface Temperature and atmospheric variables provided by the European Centre for Medium Range Weather Forecast operational analyses. At its lateral boundaries the model is one-way nested within the Mediterranean Forecasting System operational products. <br><br> The model domain has been subdivided in four sub-regions: Sardinia channel and southern Tyrrhenian Sea, Sicily channel, eastern Tunisian shelf and Libyan Sea. Temporal evolution of eddy and mean kinetic energy has been analysed, on each of the four sub-regions, showing different behaviours. On annual scales and within the first 5 m depth, the eddy kinetic energy represents approximately the 60 % of the total kinetic energy over the whole domain, confirming the strong mesoscale nature of the surface current flows in this area. The analyses show that the model well reproduces the path and the temporal behaviour of the main known sub-basin circulation features. New mesoscale structures have been also identified, from numerical results and direct observations, for the first time as the Pantelleria Vortex and the Medina Gyre. <br><br> The classical kinetic energy decomposition (eddy and mean) allowed to depict and to quantify the permanent and fluctuating parts of the circulation in the region, and to differentiate the four sub-regions as function of relative and absolute strength of the mesoscale activity. Furthermore the Baroclinic Energy Conversion term shows that in the Sardinia Channel the mesoscale activity, due to baroclinic instabilities, is significantly larger than in the other sub-regions, while a negative sign of the energy conversion, meaning a transfer of energy from the Eddy Kinetic Energy to the Eddy Available Potential Energy, has been recorded only for the surface layers of the Sicily Channel during summer

    Considerations for an Ac Dipole for the LHC

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    Following successful experience at the BNL AGS, FNAL Tevatron, and CERN SPS, an AC Dipole will be adopted at the LHC for rapid measurements of ring optics. This paper describes some of the parameters of the AC dipole for the LHC, scaling from performance of the FNAL and BNL devices.Comment: proceedings of the 2007 Particle Accelerator Conferenc

    A Neural network based observation operator for coupled ocean acoustic variational data assimilation

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    Variational data assimilation requires implementing the tangent-linear and adjoint (TA/AD) version of any operator. This intrinsically hampers the use of complicated observations.Here, we assess a new data-driven approach to assimilate acoustic underwater propagation measurements [transmission loss (TL)] into a regional ocean forecasting system. TL measurements depend on the underlying sound speed fields, mostly temperature, and their inversion would require heavy coding of the TA/AD of an acoustic underwater propagation model. In this study, the nonlinear version of the acoustic model is applied to an ensemble of perturbed oceanic conditions. TL outputs are used to formulate both a statistical linear operator based on canonical correlation analysis (CCA), and a neural network based (NN) operator. For the latter, two linearization strategies are compared, the best-performing one relying on reverse-mode automatic differentiation. The new observation operator is applied in data assimilation experiments over the Ligurian Sea (Mediterranean Sea), using the observing system simulation experiments (OSSE) methodology to assess the impact of TL observations onto oceanic fields. TL observations are extracted from a nature run with perturbed surface boundary conditions and stochastic ocean physics. Sensitivity analyses indicate that theNNreconstruction of TL is significantly better than CCA. BothCCAandNNare able to improve the upper-ocean skill scores in forecast experiments, with NN outperforming CCA on the average. The use of the NN observation operator is computationally affordable, and its general formulation appears promising for the adjoint-free assimilation of any remote sensing observing network. SIGNIFICANCE STATEMENT: Deep learning algorithms are now widely spread in a diverse range of fields to help with solving automatic classification and regression problems. Here, we present and assess a strategy aimed at introducing an observation operator based on neural networks in data assimilation. Linearization of such an operator, required by variational schemes, is also discussed and implemented. The methodology is applied to the coupled oceanic acoustic data assimilation problem, and provides promising results. Our approach may be extended in the future to assimilate any remotely sensed type of observations

    Syntaxe des proverbes binaires: coordinations et parataxes

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    Les travaux sur la binaritĂ© des proverbes n’ont cessĂ© d’apporter de nouvelles pistes de rĂ©flexion aux parĂ©miologues soucieux de dĂ©finir l’énoncĂ© sentencieux dans ses dimensions syntaxique et sĂ©mantique. Le postulat d’un schĂ©ma sĂ©mantique de fonctionnement fondĂ© sur l’implication des termes de l’énoncĂ© dĂ©veloppĂ© par Riegel puis par Anscombre et Kleiber (dĂšs 1994) permet de mieux saisir l’énoncĂ© proverbial, dont les manifestations multiples sont parfois dĂ©routantes sur le plan linguistique, notamment en raison de la complexitĂ© des liens qui unissent les diffĂ©rents Ă©lĂ©ments qui s’agencent dans tout proverbe. Le “pivot implicatif”, qui met en relation les deux membres d’un proverbe binaire est en effet prĂ©sent dans une trĂšs grande majoritĂ© d’énoncĂ©s sentencieux. Dans ce cas, l’enchaĂźnement syntaxique des membres de l’énoncĂ© peut ĂȘtre dĂ©crit grĂące Ă  l’implication sur le plan sĂ©mantique et grĂące Ă  la parataxe ou Ă  l’asyndĂšte sur le plan syntaxique, nul Ă©lĂ©ment formel ne venant prĂ©ciser le type de relation qui s’instaure entre les deux parties. En marge de ce systĂšme, pourtant, un certain nombre de proverbes remettent en question la validitĂ© de cette propriĂ©tĂ© pour l’ensemble des Ă©noncĂ©s sentencieux. L’objectif de la prĂ©sente Ă©tude est d’analyser la prĂ©sence d’autres modĂšles de fonctionnement, notamment les cas de coordination copulative et adversative, dont la structure syntaxique de surface peut avoir une incidence dans le domaine sĂ©mantique en ce sens que la relation existant entre les deux membres du proverbe peut y ĂȘtre sensiblement diffĂ©rente.Works on binary proverbs have constantly brought new thoughts to the involved researchers in order to define the sentencious postulate in its syntactic and semantic dimensions. The assumption of a semantic pattern of operation based on the involvement of the terms of the postulate developed first by Riegel, and then by Anscombre and Kleiber (as of 1994) establishes proverbial postulate. The implication, which connects the two parties of a binary proverb is certainly present in the vast majority of proverbs. In this case, the syntactical parties of the statement can be described through the semantic involvement and through parataxis or asyndeton syntactically because no formal element exists to specify the type of relationship established between both parties. In comparison to this system, however, some proverbs question the validity of this property for the overall majority of the proverbs. The objective of this research is to analyze the presence of other models (including case and copulative adversative coordination) because the syntactic structure can affect the semantic domain in the sense that the relationship between parties of the proverb may be significantly different

    Assessing the Impact of Different Ocean Analysis Schemes on Oceanic and Underwater Acoustic Predictions

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    Assimilating oceanic observations into prediction systems is an advantageous approach for real-time ocean environment characterization. However, its benefits to underwater acoustic predictions are not trivial due to the nonlinearity and sensitivity of underwater acoustic propagation to small-scale oceanic features. In order to assess the potential of oceanic data assimilation, integrated ocean-acoustic Observing System Simulation Experiments are conducted. Synthetic altimetry and in situ data were assimilated through a variational oceanographic data assimilation system. The predicted sound speed fields are then ingested in a range-dependent acoustic model for transmission loss (TL) predictions. The predicted TLs are analyzed for the purpose of (i) evaluating the contributions of different sources to the uncertainties of oceanic and acoustic forecasts and (ii) comparing the impact of different oceanic analysis schemes on the TL prediction accuracy. Using ensemble member clustering techniques, the contributions of boundary conditions, ocean parameterizations, and geoacoustic characterization to acoustic prediction uncertainties are addressed. Subsequently, the impact of three-dimensional variational (3DVAR), 4DVAR, and hybrid ensemble-3DVAR data assimilation on acoustic TL prediction at two signal frequencies (75 and 2,500 Hz) and different ranges (30 and 60 km) are compared. 3DVAR significantly improves the predicted TL accuracy compared to the control run. Promisingly, 4DVAR and hybrid data assimilation further improve the TL forecasts, the hybrid scheme achieving the highest skill scores for all cases, while being the most computationally intensive scheme. The optimal scheme choice thus depends on requirements on the accuracy and computational constraints. These findings foster developments of coupled data assimilation for operational underwater acoustic propagation
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