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Upwelling processes bring nutrient-rich waters from the deep ocean to the surface. Areas of upwelling are often associated with high productivity, offering great economic value in terms of fisheries. The sensitivity of spring/summer-time coastal upwelling systems to climate change has recently received a lot of attention. Several studies have suggested that their intensity may increase in the future while other authors have shown decreasing intensity in their equatorward portions. Yet, recent observations do not show robust evidence of this intensification. The Senegalo-Mauritanian upwelling system (SMUS) located at the southern edge of the north Atlantic system (12°N–20°N) and most active in winter/spring has been largely excluded from these studies. Here, the seasonal cycle of the SMUS and its response to climate change is investigated in the database of the Coupled Models Inter comparison Project Phase 5 (CMIP5). Upwelling magnitude and surface signature are characterized by several sea surface temperature and wind stress indices. We highlight the ability of the climate models to reproduce the system, as well as their biases. The simulations suggest that the intensity of the SMUS winter/spring upwelling will moderately decrease in the future, primarily because of a reduction of the wind forcing linked to a northward shift of Azores anticyclone and a more regional modulation of the low pressures found over Northwest Africa. The implications of such an upwelling reduction on the ecosystems and local communities exploiting them remains very uncertain.

Effective access control techniques are in demand, as electronically assisted healthcare services require the patient’s sensitive health records. In emergency situations, where the patient’s well-being is jeopardized, different healthcare actors associated with emergency cases should be granted permission to access Electronic Health Records (EHRs) of patients. The research objective of our study is to develop machine learning techniques based on patients’ time sequential health metrics and integrate them with an Attribute Based Access Control (ABAC) mechanism. We propose an ABAC mechanism that can yield access to sensitive EHRs systems by applying prognostic context handlers where contextual information, is used to identify emergency conditions and permit access to medical records. Specifically, we use patients’ recent health history to predict the health metrics for the next two hours by leveraging Long Short Term Memory (LSTM) Neural Networks (NNs). These predicted health metrics values are evaluated by our personalized fuzzy context handlers, to predict the criticality of patients’ status. The developed access control method provides secure access for emergency clinicians to sensitive information and simultaneously safeguards the patient’s well-being. Integrating this predictive mechanism with personalized context handlers proved to be a robust tool to enhance the performance of the access control mechanism to modern EHRs System.

Hydraulic fracturing drilling technology can cause a high risk of surface spill accidents and thus water contamination. Climate change together with the high water demand and rapid increase in industrial and agricultural activities are valued reasons why we should all care about the availability of water resources and protect them from contamination. Hence, the purpose of this study is to estimate the risk associated with a site contaminated with benzene from oil spillage and its potential impact on groundwater. This study focused on investigating the impact of soil variability and water table depth on groundwater contamination. Temperature-dependent parameters, such as soil water content and the diffusion of pollutants, were considered as key input factors for the HYDRUS 1D numerical model to simulate benzene migration through three types of soil (loamy, sandy clay loam, and silt loam) and evaluate its concentration in the water aquifer. The results indicated that an anticipated increase in earth’s average surface temperature by 4 °C due to climate change could lead to a rise in the level of groundwater pollution in the study area by 0.017 mg/L in loamy soil, 0.00046 mg/L in sandy clay loam soil, and 0.00023 mg/L in silt loam soil. It was found that climate change can reduce the amount of benzene absorbed from 10 to 0.07% in loamy soil, 14 to 0.07% in sandy clay loam soil, and 60 to 53% in silt loam soil. The results showed that the soil properties and solute characteristics that depend on the temperature have a major and important role in determining the level of groundwater pollutants.

Abstract For Solid Oxide Fuel Cells (SOFCs) to become an economically attractive energy conversion technology, suitable materials and structures which enable operation at lower temperatures, while retaining high cell performance, must be developed. Recently, the perovskite-type La 0.6 Ca 0.4 Fe 0.8 Ni 0.2 O 3 oxide has shown potential as an intermediate temperature SOFC cathode. An equivalent circuit describing the cathode polarization resistances was constructed from analyzing impedance spectra recorded at different temperatures in oxygen. A competitive electrode polarization resistance is reported for this oxygen electrode using a Ce 0.8 Gd 0.2 O 1.9 electrolyte, determined by impedance spectroscopy studies of symmetrical cells sintered at 800 °C and 1000 °C. Scanning electron microscopy (SEM) studies of the symmetrical cells revealed the absence of any reaction layer between cathode and electrolyte, and a porous electrode microstructure even when sintered at a temperature of only 800 °C. The performance of this cathode shows favorable oxygen reduction reaction (ORR) properties potentially making it an excellent choice for IT-SOFC application.

Biomass pre-treatment is a key step in achieving the economic competitiveness of biomass conversion. In the present work, an imidazole pre-treatment process was performed and evaluated using wheat straw and eucalyptus residues as model feedstocks for agriculture and forest-origin biomasses, respectively. Results showed that imidazole is an efficient pre-treatment agent; however, better results were obtained for wheat straw due to the recalcitrant behavior of eucalyptus residues. The temperature had a stronger effect than time on wheat straw pre-treatment but at 160 °C and 4 h, similar results were obtained for cellulose and hemicellulose content from both biomasses (ca. 54% and 24%, respectively). Lignin content in the pre-treated solid was higher for eucalyptus residues (16% vs. 4%), as expected. Enzymatic hydrolysis, applied to both biomasses after different pre-treatments, revealed that results improved with increasing temperature/time for wheat straw. However, these conditions had no influence on the results for eucalyptus residues, with very low glucan to glucose enzymatic hydrolysis yield (93% for wheat straw vs. 40% for eucalyptus residues). Imidazole can therefore be considered as a suitable solvent for herbaceous biomass pre-treatment.

Diesel engine exhausts from a common rail 3.0 L F1C diesel engine were analyzed at two different load conditions of the WLTC testing cycle downstream of both the diesel particulate filter (DPF) and selective catalytic reactor (SCR) to verify their effect on the characteristics of carbon particulate matter. An array of chemical, physical and spectroscopic techniques (gas chromatography coupled with mass spectrometry (GC-MS), mobility analyzer, UV-Visible absorption and fluorescence spectroscopy) was applied for characterizing polycyclic aromatic hydrocarbons (PAH), heavy aromatic compounds and soot, constituting the particulate matter (PM) sampled from the exhaust. The engine was operated in half load (HL) (188 Nm, representing the more common condition for engine in urban traffic) and full load (FL) (452 Nm, representing the best performance of the engine operation) conditions, at the same engine speed (2000 rpm). Soot formation was enhanced in HL condition, with respect to FL, but, just because of the much lower soot amount, the after-treatment systems in this last condition resulted to be less efficient in the soot abatement. Indeed, the abatement through DPF was about 40% lower in the FL condition with respect to HL condition, and any significant further concentration decrease was found after SCR, in both conditions. By contrast, PAH concentration after DPF abatement was found to be higher in the HL with respect to FL condition. A further PAH concentration decrease of about 30% was found after the SCR in the HL condition whereas in FL the reduction was only about 5-6%. Also the heavy aromatic compounds having molecular weight above the GC-MS detection limit (300 u), were mitigated by SCR. Therefore, SCR did not cause a further soot reduction, whereas it was effective in largely reducing PAH and heavy aromatics emissions, especially in the lower temperature condition featuring the half-load condition, when combustion efficiency is worse. Moreover, SCR system reduced the emission of small particles probably due to an enhanced agglomeration of particles, with beneficial effect on the harmfulness to human health.

Abstract The development of cleaner and renewable energy sources are needed in order to reduce fossil fuel dependence and mitigate global warming by reducing greenhouse gas emissions. Solar dryers are considered as clean technologies and optimal use of these can minimize the use of non-renewable energy, and can play an important role in the world's future. Drying for forest products is one of the most attractive and cost effective application of solar energy because it may be possible to improve forest residues in profitable biomass as biofuel. In this study, a solar greenhouse dryer was used in drying experiments of wood chips of Pinus pinaster in the south of Spain. The environmental conditions were under autumn season with an average daily solar radiation of 13.74 MJ/(m 2 d) during the 15 days of the experiment. The experiment analyzed the drying process under indoor conditions of several piles of wood chips which was compared to the same shaped piles under open sun drying. The results were mathematically modelled to show the advantages of the Solar Greenhouse Dryer for both, to reach the 10% of relative humidity and fewer days were dedicated for this. Thus, these analyses reveal that the Solar Greenhouse Dryer is a useful and vital technology for the improvement of wood chips as biofuel, it reduces moisture, and it can be applied in many countries because of the fact that it only uses solar energy; it is a renewable energy resource which is both free and clean.

A medida que las ciudades de África Oriental sigan creciendo, también lo hará la demanda de carbón vegetal, el combustible urbano preferido de la región, lo que ejercerá una presión cada vez mayor sobre los paisajes rurales donde se produce. ¿Cómo se puede hacer sostenible la producción y el suministro de carbón vegetal? ¿Cuáles son las implicaciones de las políticas y prácticas sostenibles de carbón vegetal para lograr una vía baja en carbono y proteger el medio ambiente? Este documento presenta una investigación de estudio de caso centrada en el condado de Kitui, una de las principales zonas de producción de carbón vegetal en Kenia. El riesgo y la incertidumbre de las políticas sostenibles de carbón vegetal en Kitui se evaluaron utilizando métodos complementarios de talleres con las partes interesadas, entrevistas con informantes y modelos basados en agentes. Este enfoque interdisciplinario combinó la investigación de políticas y el modelado de simulación, donde las perspectivas y los datos locales se incluyeron directamente en el modelado. Estos métodos facilitaron la crítica del comportamiento relacionado con la agencia y la corrupción. Las partes interesadas valoraron la capacidad de acceder a información detallada sobre microinteracciones y considerar el desempeño de las políticas con respecto tanto a los flujos financieros como a la extracción de biomasa. Alors que les villes d'Afrique de l'Est continuent de croître, la demande de charbon de bois – le carburant urbain préféré de la région – exercera une pression croissante sur les paysages ruraux où il est produit. Comment rendre la production et l'approvisionnement en charbon durables ? Quelles sont les implications des politiques et des pratiques de charbon de bois durable pour parvenir à une voie à faible émission de carbone et protéger l'environnement ? Cet article présente des études de cas axées sur le comté de Kitui, l'une des principales zones de production de charbon de bois au Kenya. Les risques et l'incertitude des politiques de charbon de bois durable à Kitui ont été évalués à l'aide de méthodes complémentaires d'ateliers avec les parties prenantes, d'entretiens avec les informateurs et de modélisation basée sur les agents. Cette approche interdisciplinaire combinait la recherche sur les politiques et la modélisation par simulation, où les perspectives et les données locales étaient directement incluses dans la modélisation. Ces méthodes ont facilité la critique des comportements concernant l'agence et la corruption. Les parties prenantes ont apprécié la possibilité d'accéder à des informations détaillées sur les micro-interactions et d'examiner les performances des politiques en matière de flux financiers et d'extraction de la biomasse. As cities in East Africa keep growing, so too will demand for charcoal – the region's preferred urban fuel – placing increasing pressure on rural landscapes where it is produced. How can charcoal production and supply be made sustainable? What are the implications of sustainable charcoal policies and practices for achieving a low-carbon pathway and protecting the environment? This paper presents case study research focusing on Kitui County, one of the main charcoal production areas in Kenya. Risk and uncertainty of sustainable charcoal policies in Kitui were assessed using complementary methods of stakeholder workshops, informant interviews and agent-based modelling. This interdisciplinary approach combined policy research and simulation modelling, where local perspectives and data were included directly in the modelling. These methods facilitated critique of behaviour concerning agency and corruption. Stakeholders valued the ability to access detailed information on micro-interactions and consider policy performance regarding both financial flows and biomass extraction. ومع استمرار نمو المدن في شرق أفريقيا، فإن الطلب على الفحم – الوقود الحضري المفضل في المنطقة – سيزيد من الضغط على المناظر الطبيعية الريفية حيث يتم إنتاجه. كيف يمكن جعل إنتاج الفحم وتوريده مستدامين ؟ ما هي الآثار المترتبة على سياسات وممارسات الفحم المستدامة لتحقيق مسار منخفض الكربون وحماية البيئة ؟ تقدم هذه الورقة بحث دراسة حالة يركز على مقاطعة كيتوي، واحدة من مناطق إنتاج الفحم الرئيسية في كينيا. تم تقييم المخاطر وعدم اليقين في سياسات الفحم المستدامة في كيتوي باستخدام طرق تكميلية لورش عمل أصحاب المصلحة ومقابلات المخبرين والنمذجة القائمة على الوكيل. جمع هذا النهج متعدد التخصصات بين أبحاث السياسات ونمذجة المحاكاة، حيث تم تضمين وجهات النظر والبيانات المحلية مباشرة في النمذجة. سهلت هذه الأساليب نقد السلوك المتعلق بالوكالة والفساد. وقدر أصحاب المصلحة القدرة على الوصول إلى معلومات مفصلة عن التفاعلات الصغيرة والنظر في أداء السياسات فيما يتعلق بكل من التدفقات المالية واستخراج الكتلة الحيوية.