293 research outputs found

    How Wood Fuels\u2019 Quality Relates to the Standards: A Class-Modelling Approach

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    The quality requirements of wood biofuels are regulated by a series of harmonized international standards. These standards define the technical parameter limits that influence the quality of solid biomass as a fuel. In 2014 the European reference standard for solid biofuel was replaced by the International ISO standard. In the case of wood chips, the main difference between the European and International standards is the definition of particle size distribution classes. In this context, this study analyses the quality of wood chips and its variation over the years according to the \u201cformer\u201d (EN 14691-4) and \u201cin force\u201d (ISO 17225-4) standards. A Soft Independent Modelling of Class Analogy (SIMCA) model was built to predict the best quality of wood chips and to clarify the relationship between quality and standard parameters, time and changes in the standard regulations. The results show that, compared to the EN standards, classification with the ISO standards increases the samples belonging to the best quality classes and decreases the not classified samples. Furthermore, all the SIMCA models have a high sensitivity (>90%), reflect the differences introduced to the quality standards and are therefore suitable for monitoring the quality of wood chips and their changes

    The Global Warming Potential of Building Materials: An Application of Life Cycle Analysis in Nepal

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    open6siThis paper analyzes the global-warming potential of materials used to construct the walls of 3 building types—traditional, semimodern, and modern—in Sagarmatha National Park and Buffer Zone in Nepal, using the life-cycle assessment approach. Traditional buildings use local materials, mainly wood and stone, while semimodern and modern buildings use different amounts of commercial materials, such as cement and glass wool. A comparison of the greenhouse gas emissions associated with the 3 building types, using as the functional unit 1 m2 of wall, found that traditional buildings release about one-fourth of the greenhouse gas emissions released by semimodern buildings and less than one-fifth of the emissions of modern buildings. However, the use of thermal insulation in the modern building walls helps to reduce the energy consumption for space heating and consequently to reduce the global warming potential. In 25 years, the total global warming potential of a traditional building will be 20% higher than that of a modern building. If local materials, such as wood, are used in building construction, the emissions from production and transportation could be dramatically reduced.openBhochhibhoya, Silu; Zanetti, Michela; Pierobon, Francesca; Gatto, Paola; Maskey, R. K.; Cavalli, RaffaeleBhochhibhoya, Silu; Zanetti, Michela; Pierobon, Francesca; Gatto, Paola; Maskey, R. K.; Cavalli, Raffael

    Snake and spider toxins induce a rapid recovery of function of botulinum neurotoxin paralysed neuromuscular junction

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    Botulinum neurotoxins (BoNTs) and some animal neurotoxins (-Bungarotoxin, -Btx, from elapid snakes and -Latrotoxin, -Ltx, from black widow spiders) are pre-synaptic neurotoxins that paralyse motor axon terminals with similar clinical outcomes in patients. However, their mechanism of action is different, leading to a largely-different duration of neuromuscular junction (NMJ) blockade. BoNTs induce a long-lasting paralysis without nerve terminal degeneration acting via proteolytic cleavage of SNARE proteins, whereas animal neurotoxins cause an acute and complete degeneration of motor axon terminals, followed by a rapid recovery. In this study, the injection of animal neurotoxins in mice muscles previously paralyzed by BoNT/A or /B accelerates the recovery of neurotransmission, as assessed by electrophysiology and morphological analysis. This result provides a proof of principle that, by causing the complete degeneration, reabsorption, and regeneration of a paralysed nerve terminal, one could favour the recovery of function of a biochemically- or genetically-altered motor axon terminal. These observations might be relevant to dying-back neuropathies, where pathological changes first occur at the neuromuscular junction and then progress proximally toward the cell body

    Black esophagus

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    Black esophagus is an uncommon clinical entity and its pathogenesis remains unknown. Clinical presentation is usually characterized by the combination of hematemesis and circumferential darkness of the mucosa in the distal esophagus. This case illustrates an atypical presentation of the disease. Despite its rarity, black esophagus should be considered in the differential diagnosis of acute upper gastrointestinal bleeding, especially in patients with predisposing factors. \ua9 2015 Taiwan Society of Emergency Medicine

    Development of Quebracho (Schinopsis balansae) Tannin-Based Thermoset Resins

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    One of the major challenges currently in the field of material science is finding natural alternatives to the high-performing plastics developed in the last century. Consumers trust synthetic products for their excellent properties, but they are becoming aware of their impact on the planet. One of the most attractive precursors for natural polymers is tannin extracts and in particular condensed tannins. Quebracho (Schinopsis balansae) extract is one of the few industrially available flavonoids and can be exploited as a building block for thermoset resins due to its phenol-like reactivity. The aim of this study was to systematically investigate different hardeners and evaluate the water resistance, thermal behavior, and chemical structure of the quebracho tannin-based polymers in order to understand their suitability as adhesives. It was observed that around 80% of the extract is resistant to leaching when 5% of formaldehyde or hexamine or 10% of glyoxal or furfural are added. Additionally, furfuryl alcohol guarantees high leaching resistance, but only at higher proportions (20%). The quebracho-based formulations showed specific thermal behavior during hardening and higher degradation resistance than the extract. Finally, these polymers undergo similar chemistry to those of mimosa, with exclusive reactivity of the A-ring of the flavonoid

    Lack of Fibronectin Extra Domain A Alternative Splicing Exacerbates Endothelial Dysfunction in Diabetes

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    Glucose-induced changes of artery anatomy and function account for diabetic vascular complications, which heavily impact disease morbidity and mortality. Since fibronectin containing extra domain A (EDA\u2009+\u2009FN) is increased in diabetic vessels and participates to vascular remodeling, we wanted to elucidate whether and how EDA\u2009+\u2009FN is implicated in diabetes-induced endothelial dysfunction using isometric-tension recording in a murine model of diabetes. In thoracic aortas of EDA(-/-), EDA(+/+) (constitutively lacking and expressing EDA\u2009+\u2009FN respectively), and of wild-type mice (EDA(wt/wt)), streptozotocin (STZ)-induced diabetes impaired endothelial vasodilation to acetylcholine, irrespective of genotype. However STZ\u2009+\u2009EDA(-/-) mice exhibited increased endothelial dysfunction compared with STZ\u2009+\u2009EDA(+/+) and with STZ\u2009+\u2009EDA(wt/wt). Analysis of the underlying mechanisms revealed that STZ\u2009+\u2009EDA(-/-) mice show increased oxidative stress as demonstrated by enhanced aortic superoxide anion, nitrotyrosine levels and expression of NADPH oxidase NOX4 and TGF-\u3b21, the last two being reverted by treatment with the antioxidant n-acetylcysteine. In contrast, NOX1 expression and antioxidant potential were similar in aortas from the three genotypes. Interestingly, reduced eNOS expression in STZ\u2009+\u2009EDA(+/+) vessels is counteracted by increased eNOS coupling and function. Although EDA\u2009+\u2009FN participates to vascular remodelling, these findings show that it plays a crucial role in limiting diabetic endothelial dysfunction by preventing vascular oxidative stress

    Epidemic of tuberculosis in a high school in Northern Sardinia

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    Abstract The aim of this study was to investigate the Mycobacterium tuberculosis transmission among high school student and teacher populations in a high school in Northern Sardinia. Tuberculin skin-test screening, chest-X-rays, QuantiFERON-TB Gold, microbiological examination, spoligotyping and variable numbers of tandem repeats (VNTR) analysis of M. tuberculosis isolates were performed. This study indicates the effectiveness of the epidemiological investigation

    Surface finishes by mechanically induced wood surface fusion

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    Mechanically induced vibration wood fusion welding techniques can also be used to obtain wood surface finishes of increased surface hardness and performance in presence of polymerizing unsaturated oils such as sunflower oil, or other polymerizing finishes. Wood surface hardness values more than double than those for the untreated control timber can be obtained by this method. This result is obtained due to two effects induced by the sharp increase in temperature induced by the mechanical welding vibration (i) the polymerization to a hardened network of the unsaturated oil and (ii) the densification proven to occur in the surface layer of the timber during mechanically-induced vibration-welding. The first of these effects predominates at shorter welding times while at slightly longer welding times both effects occur with the second one progressively becoming the bigger contributor. In the latter case the some μm thin densified surface is a surface composite formed by the networked unsaturated oil permeating the wood fibre/fused lignin composite. © Springer-Verlag 2005

    Identifying reliable predictors of protein-energy malnutrition in hospitalized frail older adults. A prospective longitudinal study

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    BACKGROUND: Decreased food intake is a risk factor for relevant complications (e.g. infections, pressure ulcers), longer hospital stays, higher readmission rates, greater health care costs and increased patient mortality, particularly in frail hospitalized older adults who are malnourished or at risk of malnutrition. Nurses are called to improve this criticality, starting from accurately identify patients for malnutrition at hospital admission and effectively monitoring their food intake. OBJECTIVES: The primary aim was to identify reliable predictive indicators of reduced food intake at hospital admission. The secondary aims were to assess the adequacy of daily energy and protein intake and the impact of nutrient intake on patient outcomes. DESIGN: Prospective observational longitudinal study. SETTING: Internal Medicine Ward of an Academic Teaching University Hospital. PARTICIPANTS: Acute older adults who were malnourished or at risk of malnutrition (Nutritional Risk Score-2002\u202f 65\u202f3, middle-upper arm circumference\u2009<23.5\u202fcm or impaired self-feeding ability) at admission. METHODS: The effective energy and protein intake was monitored during the first 5\u202fdays of hospital stay by a photographic method and compared to the daily energy and protein requirement calculated by specific equations. Data on anthropometry, inflammation/malnutrition laboratory data and body composition (phase\u202fangle calculated using bioelectrical impedance analysis) were collected. RESULTS: Eighty-one subjects (age 81.5\u202f\ub1\u202f11.5\u202fyears) were enrolled. Mean energy intake was 669.0\u202f\ub1\u202f573.9\u202fkcal/day, and mean protein intake was 30.7\u202f\ub1\u202f25.8\u202fg/day. Over 60% of patients ingested\u2009 6450% of their calculated energy and protein requirements: these patients were older (p\u202f=\u202f0.026), had a lower middle-upper arm circumference (p\u202f=\u202f0.022) and total arm area (p\u202f=\u202f0.038), a higher C-reactive protein/albumin ratio and Instant Nutritional Assessment score (p\u202f<\u202f0.01), and experienced longer hospital stays (p\u202f 64\u202f0.04) and higher in-hospital and 30-day post-discharge mortality (p\u202f<\u202f0.001). In the multivariate analysis, lower middle-upper arm circumference, higher C-reactive protein/albumin ratio, and impaired self-feeding at admission were independently associated with critically reduced energy and protein intake. CONCLUSIONS: Middle-upper arm circumference, C-reactive protein/albumin ratio, and impaired self-feeding are easily obtainable indicators of impaired energy and protein intake and poor clinical outcomes. Such parameters should be adopted as screening criteria to assess the risk for critically reduced energy/protein intake in hospitalized older adults. These findings are relevant to improve clinical practice through the implementation of multidisciplinary strategies, given the adverse clinical outcomes related to hospital malnutrition
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