1,311 research outputs found

    Production of gaseous and liquid bio-fuels from the upgrading of lignocellulosic bio-oil in sub- and supercritical water: effect of operating conditions on the process

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    This work analyses the influence of the temperature (310–450 C), pressure (200–260 bar), catalyst/biooil mass ratio (0–0.25 g catalyst/g bio-oil), and reaction time (0–60 min) on the reforming in sub- and supercritical water of bio-oil obtained from the fast pyrolysis of pinewood. The upgrading experiments were carried out in a batch micro-bomb reactor employing a co-precipitated Ni–Co/Al–Mg catalyst. This reforming process turned out to be highly customisable for the valorisation of bio-oil for the production of either gaseous or liquid bio-fuels. Depending on the operating conditions and water regime (sub/supercritical), the yields to upgraded bio-oil (liquid), gas and solid varied as follows: 5–90%, 7–91% and 3–31%, respectively. The gas phase, having a LHV ranging from 2 to 17 MJ/m3 STP, was made up of a mixture of H2 (9–31 vol.%), CO2 (41–84 vol.%), CO (1–22 vol.%) and CH4 (1–45 vol.%). The greatest H2 production from bio-oil (76% gas yield with a relative amount of H2 of 30 vol.%) was achieved under supercritical conditions at a temperature of 339 C, 200 bar of pressure and using a catalyst/bio-oil ratio of 0.2 g/g for 60 min. The amount of C, H and O (wt.%) in the upgraded bio-oil varied from 48 to 74, 4 to 9 and 13 to 48, respectively. This represents an increase of up to 37% and 171% in the proportions of C and H, respectively, as well as a decrease of up to 69% in the proportion of O. The HHV of the treated bio-oil shifted from 20 to 35 MJ/kg, which corresponds to an increase of up to 89% with respect to the HHV of the original bio-oil. With a temperature of around 344 C, a pressure of 233 bar, a catalyst/bio-oil ratio of 0.16 g/g and a reaction time of 9 min a compromise was reached between the yield and the quality of the upgraded liquid, enabling the transformation of 62% of the bio-oil into liquid with a HHV (29 MJ/kg) about twice as high as that of the original feedstock (17 MJ/kg)

    Predictors of unintentional childhood injuries seen at the Accident and Emergency Units of three tertiary health care centres in Jos

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    Background: Unintentional childhood injuries pose a major health challenge especially in developing countries.Aim: This study sought to determine the predictors of unintentional childhood injuries in the three tertiary health centres studied.Methods: The study was a cross- sectional study. Sociodemographic data, history and physical examination, type of injury and the outcomes were obtained using structured questionnaire. Results: A total of 174 children were enrolled, 108 (62.1%) were males and 66 (37.9%) were females; 63 (36.2%) were < 5years while 65 (37.4%) were>10 years. Of the injuries observed; 99 (56.9%) were by vehicular objects, 15 (8.6%) were burns, 41 (23.6%) were from falls and 19 (10.9%) poisoning. Those who were treated as outpatients were 141 (81.0%) and 25 (14.4%) were admitted for inpatient care. About ninety four percent (94.3%) of the children had no significant effect or disability, 3.4% had short-term disability while 2.3% had long term disabilities or died post-injury. There was no statistically significant relationship between the age of the subjects, gender, duration of the injury prior to presentation and the educational status of their care givers with the pattern of the injury.Conclusion: This study showed that 81% (141) of the children studied were treated as outpatients, 56.9% were by vehicular objects, 62.1% were in males and the pattern of injuries were not related to age, gender, educational status of care givers, place or time of injuries. There is need to incorporate these findings in the provision of preventive messages in school health services and in the interventions targeting the safety of children against injuries. Further studies to identify risk factors and plan necessary interventions will also be necessary.Keywords: Predictors, unintentional, childhood injuries, emergency departments, out-patient, tertiary health centre

    ValoraciĂłn eco-pastoral de los pastos del Monte Lakora (Navarra, Pirineo occidental)

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    7 páginasSe aplica el método del índice eco-pastoral, desarrollado en trabajos previos, a los pastos del monte Lakora (Navarra) situado en el Pirineo occidental. Se ha utilizado un mapa de vegetación digitalizado (escala 1/5.000). Las comunidades de Primulion intricatae, Nardion strictae, brezales subalpinos de Vaccinium uliginosum y pastos de Festuca eskia son los que tienen un mayor valor ecológico. Las comunidades de Bromion erecti y Primulion intricatae son las que tienen un mayor valor pastoral potencial. El monte Lakora presenta un valor ecológico mayor que el pastoral, por lo que se justifica su inclusión dentro del Lugar de Importancia Comunitaria (LIC) “ES2200001 Larra-Aztaparreta” así como la priorización de su conservación mediante el adecuado manejo ganadero.Peer reviewe

    SEOM-GECP-GETTHI Clinical Guidelines for the treatment of patients with thymic epithelial tumours (2021)

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    Chemotherapy; Lenvatinib; Thymic epithelial tumoursQuimioterapia; lenvatinib; Tumores epiteliales tĂ­micosQuimioterĂ pia; Lenvatinib; Tumors epitelials tĂ­micsThymic epithelial tumours (TET) represent a heterogeneous group of rare malignancies that include thymomas and thymic carcinoma. Treatment of TET is based on the resectability of the tumour. If this is considered achievable upfront, surgical resection is the cornerstone of treatment. Platinum-based chemotherapy is the standard regimen for advanced TET. Due to the rarity of this disease, treatment decisions should be discussed in specific multidisciplinary tumour boards, and there are few prospective clinical studies with new strategies. However, several pathways involved in TET have been explored as potential targets for new therapies in previously treated patients, such as multi-tyrosine kinase inhibitors with antiangiogenic properties and immune checkpoint inhibitors (ICI). One third of patient with thymoma present an autoimmune disorders, increasing the risk of immune-related adverse events and autoimmune flares under ICIs. In these guidelines, we summarize the current evidence for the therapeutic approach in patients with TET and define levels of evidence for these decisions

    Sélection du régime alimentaire chez la Marmotte des Alpes (Marmota m. marmota L.) dans les Pyrénées

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    We studied the diet composition and selection of plants in the Alpine marmot Marmota m. marmota of two family groups in the Western Pyrenees from May to September. The food consumed was determined by faecal analysis, and the plant selection was determined comparing the plant composition in faeces and plant availability in the area surrounding the marmot burrows, which was measured by the point-intercept method. Most of the available plants belonged to a few families whose abundance did not change remarkably through the studied months, although the plants’ phenological stage changed considerably. The Alpine marmots primarily ate plants, consisting of a wide variety of leaves, flowers, and fruits of grasses and forbs, although the leaves of dicotyledonous herbs clearly dominated in the overall diet. Leguminosae, Compositae, Liliaceae, Plantaginaceae, and Umbelliferae were positively selected, and Labiatae and Rubiaceae were avoided. Flowers were actively chosen on the basis of relative abundance and phenology. The ingestion of animal prey (Arthropoda) was confirmed at the beginning of the active seasonNous avons étudié de mai à septembre dans les Pyrénées occidentales la composition du régime alimentaire et la sélection des plantes dans deux groupes familiaux de Marmotte des Alpes Marmota m. marmota. La nourriture consommée a été déterminée par analyse des fèces et la sélection des plantes en comparant la composition des fèces au cortège de plantes disponibles dans la zone entourant les terriers des marmottes. La plupart des plantes disponibles n'appartenaient qu'à quelques familles dont l'abondance ne changea pas de manière remarquable durant les mois d'étude contrairement aux stades phénologiques des plantes. Les marmottes ont surtout consommé des végétaux consistant en une grande variété de feuilles, de fleurs et de graines de graminées et autres herbes, les feuilles de dicotylédones dominant nettement dans le régime. Les Légumineuses, Composées, Liliacées, Plantaginacées et Ombellifères étaient positivement sélectionnées ; les Labiées et les Rubiacées étaient évitées. Les fleurs étaient activement choisies sur la base de leur abondance relative et de leur phénologie. L'ingestion de proies animales (Arthropodes) a été confirmée au début de la saison d'activité

    Volumetric multiple optical traps produced by Devil's lenses

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    We propose the use of a new diffractive optical element coined Devil's Vortex-Lens (DVL) to produce optical tweezers. In its more general form it results as the combination of a Devil’s lens and a helical vortex phase mask. It is shown that under monochromatic illumination a DVL generates a focal volume with several concatenated doughnut modes that are axially distributed according to the self-similarity of the lens. The orbital angular momentum associated to each link in the chain is investigated
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