903 research outputs found

    Geopolymers reinforced with natural fibers: A comparison among different sources

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    The performance of different natural fibers (hemp, kenaf and bamboo) used to formulate composites with an alkali-activated matrix based on metakaolin is evaluated. Short fibers were randomly dispersed up to about 3% of the binder weight, and the fresh and cured properties of the derived composites were determined. Up to the investigated fraction, it is still possible to obtain adequate workability without the supply of additional water or additives. Upon modification with fibers, the mechanical behavior changes from completely brittle to pseudoplastic with increased toughness. The flexural strength increases by up to 80% at the highest bamboo amount and up to 20% for kenaf. Hemp fibers have a negligible effect on flexural strength but strongly improve the materials’ toughness. Moreover, the addition of fibers does not change the manner in which the material interacts with moisture. Indeed, the water uptake of the modified samples was comparable to that of the unmodified samples, and the composites showed a decreased rate of water diffusion as the amount of fiber increased

    A New Geographic Information System (GIS) Tool for Hydrogen Value Chain Planning Optimization: Application to Italian Highways

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    Optimizing the hydrogen value chain is essential to ensure hydrogen market uptake in replacing traditional fossil fuel energy and to achieve energy system decarbonization in the next years. The design of new plants and infrastructures will be the first step. However, wrong decisions would result in temporal, economic losses and, in the worst case, failures. Because huge investments are expected, decision makers have to be assisted for its success. Because no tools are available for the optimum design and geographical location of power to gas (P2G) and power to hydrogen (P2H) plants, the geographic information system (GIS) and mathematical optimization approaches were combined into a new tool developed by CNR-ITAE and the University of Bologna in the SuperP2G project, aiming to support the interested stakeholders in the investigation and selection of the optimum size, location, and operations of P2H and P2G industrial plants while minimizing the levelized cost of hydrogen (LCOH). In the present study, the tool has been applied to hydrogen mobility, specifically to investigate the conversion of the existing refuelling stations on Italian highways to hydrogen refuelling stations (HRSs). Middle-term (2030) and long-term (2050) scenarios were investigated. In 2030, a potential demand of between 7000 and 10,000 tons/year was estimated in Italy, increasing to between 32,600 and 72,500 tons/year in 2050. The optimum P2H plant configuration to supply the HRS was calculated in different scenarios. Despite the optimization, even if the levelized cost of hydrogen (LCOH) reduces from 7.0-7.5 euro/kg in 2030 to 5.6-6.2 euro/kg in 2050, the results demonstrate that the replacement of the traditional fuels, i.e., gasoline, diesel, and liquefied petroleum gases (LPGs), will be disadvantaged without incentives or any other economic supporting schemes

    From food waste to eco-friendly functionalized polymer composites: Investigation of orange peels as active filler

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    : The development of eco-friendly polymer composites with multifunctional properties aligns with the goals of the circular economy agenda, which aims to minimize waste and promote the sustainable use of resources by closing the loop of product life cycles. Eco-friendly polymer composites play a crucial role in achieving these objectives. The present work focuses on the preparation of fully biobased blends obtained by melt mixing a bio-polyester, poly(butylene succinate-co-adipate) (PBSA), with orange peels up to 20 wt%, to yield active polymer composites. Orange peels, employed here as natural filler, are largely available from food wastes, they are rich in phenolic compounds and possess antioxidant activity as shown by the experimental tests carried out. The thermal stability of the formulated composites is almost unchanged by the filler addition, showing only a slight decrease of the crystallization temperatures and crystalline fraction within the composites. The mechanical properties of the compounds evidence an increase in the elastic modulus together with a decrease in the tensile strength, while the elongation at break remains almost constant. The incorporation of the natural filler enabled the integration of antioxidant and antibacterial properties, which were absent in the original pristine polymer

    Deparaffination time: a crucial point in histochemical detection of tissue copper

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    The search for a sensitive histochemical method for revealing tissue copper has been the object of many workers in the past. In spite of multiple methods available, the occurrence in clinical practice of negative histochemical stains, even in cases with high copper levels demonstrated by quantitative methods is very high. This study was aimed at verifying the role of technical variations in the sensitivity of the Timm method and, in particular, the role of the dewaxing time of paraffin sections. To this end, 15 liver specimens, 10 from patients affected by Wilson's disease and 5 newborn livers were fixed in 10% formalin, paraffin embedded and routinaly processed. Four 4-micron sections from each case were rinsed in xylene for 10, 20, 60 min, and for 24 hrs. All sections were stained with Timm's method. In 13 out of the 15 liver biopsies utilized in this study, the sensitivity of Timm's method in revealing copper deposits in liver cells appeared to be dependent on the dewaxing time. In two other cases, reactivity of copper granules to Timm solution did not change significantly with the different deparaffination times. The best results were obtained by rinsing sections in xylene for 24 hrs, the worst in sections treated with xylen for 10 minutes. In particular, in five cases of Wilson's disease, Timm stain applied to sections following ten minutes of xylene were completely negative, while copper granules were clearly evidenced in the same section following an overnight bath in xylene. Our data show that an overnight bath of paraffin sections in xylene may completely change the sensitivity of Timm stain in revealing copper deposits in the liver, relaunching copper histochemistry in the diagnosis of copper-related liver diseases

    Midwives autonomy in discharge women after physiological childbirth

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    BACKGROUND: International literature identifies the midwife as the professional figure deals with women and newborns in the context of childbirth; it is however found to be still difficult to ensure this continuity of care. In Italy both the national laws and the indications of Emilia Romagna region promote this practice, ensuring the midwives management of the low risk women immediately after childbirth. The aim of the study is to investigate and describe the midwives autonomy as regards the post-partum discharge. METHODS: The computerised medical records were consulted to identify the mothers after childbirth who can be discharged independently by the obstetrician following the guidelines of the Emilia-Romagna region. RESULT S: A retrospective analysis of 1371 medical records related to the period January-June 2017 showed that 41% of discharges were managed handled by the midwives, while the remaining 59% by obstetricians. Fifty-seven percent of the women followed by the family counselling service were discharged by the obstetricians and 43% independently by the midwives. Considering the women followed by a private physician 62% were discharged by the obstetricians and 38% by the midwives. CONCLUSIONS: The study shows that, in a short time from the beginning of the project, the results as regards midwives autonomy were excellent. Indeed the midwives discharges does not differed significantly from the medical ones, and care continuity between the hospital and territory is strengthened. Further studies must include questionnaires concerning satisfaction of the mother not administered in this sample of women

    Triassic MORB magmatism in the Southern Mirdita zone (Albania)

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    In southern Albania the Mirdita Ophiolitic nappe is characterized by subophiolitic complexes in which remnants of volcanic ophiolite sequences of Triassic age have been identified, either as rare blocks of variable dimension in the Rubik Complex, or as a thin tectonic unit (the Porava Unit), sited immediately under the main ophiolitic masses of the Eastern Ophiolite Belt. In this paper the results of petrological investigations on basalts and biostratigraphical studies on associated radiolarian cherts included in these subophiolitic complexes units are presented. Biostratigraphical investigations indicate that cherts have ages ranging from Middle to Late Triassic. The associated basalts are represented by both high-Ti mid-ocean ridge basalts (MORB) and alkaline ocean island basalts (OIB). MORB rocks mainly consist of basalts and ferrobasalts with a mild enrichment in low field strength elements and flat rare earth element patterns and, subordinately, by basalts strongly depleted in incompatible elements and light rare earth elements. The chemistry of slightly enriched MORB is consistent with a generation in a mid-ocean ridge setting, from somewhat enriched sub-oceanic mantle source(s), whereas depleted MORB generated from a primitive MOR-type mantle source. The OIB rocks imply a generation in a within-plate oceanic setting from a mantle source enriched by plume chemical components. Basalts and associated cherts from southern Albania subophiolitic mélanges represent remnants of a Triassic oceanic lithosphere, which testify for the existence, from northern Albania to southern Greece, of a Middle to Late Triassic oceanic basin located between the Adria and Eurasia plates. The occurrence in the Rubik Complex and Porava Unit of MOR basalts generated from differently enriched sources, as well as of alkaline OIBs, suggests that the early stage of oceanic spreading was variably associated with a plume activity

    The prevention of doping and the improper use of drugs and food supplements in sports and physical activities: a survey on the activity of the prevention departments of Italian local health authorities

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    Doping is an important public health problem widespread not only among elite athletes, but also among amateur and recreational athletes and the general population. In Italy the introduction of doping prevention within the Essential Levels of Care (LEA) with the DPCM 12/1/2017 represents a crucial step towards the implementation of education and health promotion interventions. In this context, the Departments of Prevention (DP) of the Local Health Authorities (LHA) have to play a fundamental role, becoming the cultural and operational reference on this issue. As part of the "Doping prevention: development of a permanent educational tool coordinated by the National Health Service Prevention Departments" project, funded by the Italian Ministry of Health, a survey was conducted on the activities carried out by the DP regarding doping prevention and improper use and abuse of drugs and food supplements in sports and physical activities, as a basis for the harmonization of organizational structures and prevention programs and the creation of a collaboration network at a regional and national level
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