129 research outputs found

    Isothermal calorimetry protocols to monitor the shelf life and aftermarket follow-up of fresh cut vegetables

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    Protocols and guidelines were assessed in order to apply isothermal calorimetry as a complementary/alternative method to monitoring, during the shelf life and the microbial growth/metabolism in commercial fresh cut vegetables with random initial microbial population. Moreover, the endogenous microbial population was used as a biosensor to check the modifications occurred during long storage for aftermarket characterization in the frame of vegetable waste treatments. Validation was obtained following ready-to-use carrots highlighting the effects of the different exposed surfaces (cylinders, sticks and a`-la-julienne cut) on the overall spoiling process during shelf life and green salad stored up to 14 days with regard to the aftermarket characterization

    Diurnal tracking of anthropogenic CO_2 emissions in the Los Angeles basin megacity during spring 2010

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    Attributing observed CO_2 variations to human or natural cause is critical to deducing and tracking emissions from observations. We have used in situ CO_2, CO, and planetary boundary layer height (PBLH) measurements recorded during the CalNex-LA (CARB et al., 2008) ground campaign of 15 May–15 June 2010, in Pasadena, CA, to deduce the diurnally varying anthropogenic component of observed CO_2 in the megacity of Los Angeles (LA). This affordable and simple technique, validated by carbon isotope observations and WRF-STILT (Weather Research and Forecasting model – Stochastic Time-Inverted Lagrangian Transport model) predictions, is shown to robustly attribute observed CO_2 variation to anthropogenic or biogenic origin over the entire diurnal cycle. During CalNex-LA, local fossil fuel combustion contributed up to ~50% of the observed CO_2 enhancement overnight, and ~100% of the enhancement near midday. This suggests that sufficiently accurate total column CO_2 observations recorded near midday, such as those from the GOSAT or OCO-2 satellites, can potentially be used to track anthropogenic emissions from the LA megacity

    Comparison of mixed layer heights from airborne high spectral resolution lidar, ground-based measurements, and the WRF-Chem model during CalNex and CARES

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    The California Research at the Nexus of Air Quality and Climate Change (CalNex) and Carbonaceous Aerosol and Radiative Effects Study (CARES) field campaigns during May and June 2010 provided a data set appropriate for studying the structure of the atmospheric boundary layer (BL). The NASA Langley Research Center (LaRC) airborne high spectral resolution lidar (HSRL) was deployed to California onboard the NASA LaRC B-200 aircraft to aid in characterizing aerosol properties during these two field campaigns. Measurements of aerosol extinction (532 nm), backscatter (532 and 1064 nm), and depolarization (532 and 1064 nm) profiles during 31 flights, many in coordination with other research aircraft and ground sites, constitute a diverse data set for use in characterizing the spatial and temporal distribution of aerosols, as well as the depth and variability of the daytime mixed layer (ML) height. The paper describes the modified Haar wavelet covariance transform method used to derive the ML heights from HSRL backscatter profiles. HSRL ML heights are validated using ML heights derived from two radiosonde profile sites during CARES. Comparisons between ML heights from HSRL and a Vaisala ceilometer operated during CalNex were used to evaluate the representativeness of a fixed measurement over a larger region. In the Los Angeles basin, comparisons of ML heights derived from HSRL measurements and ML heights derived from the ceilometer result in a very good agreement (mean bias difference of 10 m and correlation coefficient of 0.89) up to 30 km away from the ceilometer site, but are essentially uncorrelated for larger distances, indicating that the spatial variability of the ML height is significant over these distances and not necessarily well captured by limited ground stations. The HSRL ML heights are also used to evaluate the performance in simulating the temporal and spatial variability of ML heights from the Weather Research and Forecasting Chemistry (WRF-Chem) community model. When compared to aerosol ML heights from HSRL, thermodynamic ML heights from WRF-Chem were underpredicted in the CalNex and CARES regions, shown by a bias difference value of −157 m and −29 m, respectively. Better agreement over the Central Valley than in mountainous regions suggests that some variability in the ML height is not well captured at the 4 km grid resolution of the model. A small but significant number of cases have poor agreement when WRF-Chem consistently overestimates the ML height in the late afternoon. Additional comparisons with WRF-Chem aerosol mixed layer heights show no significant improvement over thermodynamic ML heights, confirming that any differences between measurement and model are not due to the methodology of ML height determination

    Association Between Affective-Cognitive Symptoms of Depression and Exacerbation of Crohn’s Disease

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    The prevalence of depression is high in patients with Crohn’s Disease (CD). We examined the influence of affective-cognitive symptoms of depression on the risk of exacerbation of CD

    Learning to live together: a challenge for schools located in contexts of social vulnerability

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    Currently, there are many educational centres that demonstrate the need to promote initiatives to improve coexistence at school at the international level, especially in those located in contexts of social vulnerability. A socio-educational programme has been developed, applied and evaluated at a Singular Education Action Centre (Centro de AcciĂłn Educativa Singular - C.A.E.S) in the city of Valencia (Spain). To ascertain the programme's impact and possible generalization to other contexts, a quasi-experimental pretest-posttest design with a control group was used. Information was collected from 297 students and 54 teachers based on questionnaires assessing coexistence at school. The results obtained demonstrate the satisfactory functioning of the programme. The faculty and students from the experimental group affirm the importance of continuing to work in this direction to invest in creating a democratic school that firmly believes in coexistence and participation. Areas for improvement include the need to incorporate actions to increase family participation and develop strategies to facilitate the implementation of a more comprehensive programme

    Diurnal tracking of anthropogenic CO<sub>2</sub> emissions in the Los Angeles basin megacity during spring 2010

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    Attributing observed CO2 variations to human or natural cause is critical to deducing and tracking emissions from observations. We have used in situ CO2, CO, and planetary boundary layer height (PBLH) measurements recorded during the CalNex-LA (CARB et al., 2008) ground campaign of 15 May–15 June 2010, in Pasadena, CA, to deduce the diurnally varying anthropogenic component of observed CO2 in the megacity of Los Angeles (LA). This affordable and simple technique, validated by carbon isotope observations and WRF-STILT (Weather Research and Forecasting model – Stochastic Time-Inverted Lagrangian Transport model) predictions, is shown to robustly attribute observed CO2 variation to anthropogenic or biogenic origin over the entire diurnal cycle. During CalNex-LA, local fossil fuel combustion contributed up to ~50% of the observed CO2 enhancement overnight, and ~100% of the enhancement near midday. This suggests that sufficiently accurate total column CO2 observations recorded near midday, such as those from the GOSAT or OCO-2 satellites, can potentially be used to track anthropogenic emissions from the LA megacity

    COVID-19 first lockdown as a window into language acquisition: Associations between caregiver-child activities and vocabulary gains

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    The COVID-19 pandemic, and the resulting closure of daycare centers worldwide, led to unprecedented changes in children’s learning environments. This period of increased time at home with caregivers, with limited access to external sources (e.g., daycares) provides a unique opportunity to examine the associations between the caregiver-child activities and children’s language development. The vocabularies of 1742 children aged8-36 months across 13 countries and 12 languages were evaluated at the beginning and end of the first lockdown period in their respective countries(from March to September 2020). Children who had less passive screen exposure and whose caregivers read more to them showed larger gains in vocabulary development during lockdown, after controlling for SES and other caregiver-child activities. Children also gained more words than expected (based on normative data) during lockdown; either caregivers were more aware of their child’s development or vocabulary development benefited from intense caregiver-child interaction during lockdown
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