40 research outputs found

    Evaluating by LCA the environmental impact savings related to the use of waste incineration bottom ash in porcelain tiles manufacturing: The role of metals recovery

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    The implementation of circular economy concepts in industrial manufacturing is being promoted in many Countries, in particular by the EU. The evaluation of the economic and environmental savings related to the decrease of the amounts of waste sent to final disposal and also of the impacts of the extraction of raw materials, are of particular relevance to companies. In particular, Life Cycle Assessment (LCA) and footprint analysis are being increasingly applied with the aim of attaining Environmental Product Declarations (EPDs) to prove to potential customers how “greener” the products achieved employing circular routes are compared to those attained via traditional linear processes. It should be noted however, that the environmental advantages that can be achieved can vary significantly according to the specific characteristics of the system in question, such as the current strategies applied for managing the waste, the types and amounts of raw materials that are replaced and the distance of supply of each type of material (both for the waste and raw materials). A type of waste material that is currently being increasingly used outside of landfills is waste incineration bottom ash. This material is employed as aggregates or sand substitutes in concrete or asphalt mixtures, as aggregates in unbound applications, or as raw material in cement or recently also ceramics manufacturing. In any case, the bottom ash is first treated to recover ferrous and non-ferrous metals and may undergo different treatments such as particle size separation, crushing, washing, natural weathering and/or binder addition, in view of the intended application. In this study, we focused on the relevance of some of the input parameters and assumptions on the environmental impacts resulting for a cradle to gate LCA case study concerning a manufacturing process employing waste incineration bottom ash. Specifically, data from a company in Central Italy that has started a production line of porcelain stoneware tiles using waste incineration bottom ash in partial replacement of feldspar sands was employed to evaluate the environmental impacts related to the manufacturing of the new product, comparing them to those of the same type of tiles produced using only quarried material. From the comparison of the environmental performances related to the production of the two types of products (stoneware tiles with and without bottom ash) assessed employing the EPD 2018 method and Simapro 9.1.1 software, the production of the tile containing the bottom ash compared to that obtained by the traditional process would in particular involve a significant decrease of the following impacts: mineral consumption and eutrophication (70%), photochemical smog and acidification (40-45%) and climate change (25%). In particular, the results showed that the reduction of the impacts is not so much linked to the impacts avoided for the extraction and transport of feldspar replaced by bottom ash, as to the recovery of ferrous and non-ferrous metals from the bottom ash implemented in the tiles manufacturing plant. It is evident hence that the results are strongly dependent on the assumptions made regarding the amounts of iron and aluminum that can be recovered and the processes assumed for their recovery. In particular, the substitution of primary steel and aluminum production were considered, although the impacts related to secondary steel and aluminum production were accounted for and substitution ratios lower than 1 were considered. It should be highlighted that for the analyzed case study it was considered that the bottom ash would be treated for metal recovery at the plant and would be diverted from landfills. If instead pre-treated bottom ash intended for reuse as aggregates were employed in the tile production process, the potential environmental benefits that could be achieved would be significantly lower. At the Conference the results of the study, and in particular the effects of the assumptions made on ferrous and non-ferrous metals recovery, with regard to amounts, quality and utilization/substitution scenarios, as well as of the management options for the bottom ash and transport distances, will be assessed in terms of their overall effect on the environmental impact savings of the examined circular economy process

    Development of an experimental test rig for cogeneration based on a Stirling engine and a biofuel burner

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    A system consisting of a last-generation Stirling engine (SE) and a fuel burner for distributed power generation has been developed and experimentally investigated. The heat generated by the combustion of two liquid fuels, a standard Diesel fuel and a rapeseed oil, is used as a heat source for the SE, that converts part of the thermal energy into mechanical and then electric energy. The hot head of the SE is kept in direct contact with the flame generated by the burner. The burner operating parameters, designed for Diesel fuel, were changed to make it possible to burn vegetable oils, not suitable for internal combustion engines. The possibility of adopting different configurations of the combustion chamber was taken into account to increase the system efficiency. The preliminary configurations adopted allowed to operate this integrated system, obtaining an electric power up to 4.4 kW(el)with a net efficiency of 11.6%

    One-loop effective potential for SO(10) GUT theories in de Sitter space

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    Zeta-function regularization is applied to evaluate the one-loop effective potential for SO(10) grand-unified theories in de Sitter cosmologies. When the Higgs scalar field belongs to the 210-dimensional irreducible representation of SO(10), attention is focused on the mass matrix relevant for the SU(3)xSU(2)xU(1) symmetry-breaking direction, to agree with low-energy phenomenology of the particle-physics standard model. The analysis is restricted to those values of the tree-level-potential parameters for which the absolute minima of the classical potential have been evaluated. As shown in the recent literature, such minima turn out to be SO(6)xSO(4)- or SU(3)xSU(2)xSU(2)xU(1)-invariant. Electroweak phenomenology is more naturally derived, however, from the former minima. Hence the values of the parameters leading to the alternative set of minima have been discarded. Within this framework, flat-space limit and general form of the one-loop effective potential are studied in detail by using analytic and numerical methods. It turns out that, as far as the absolute-minimum direction is concerned, the flat-space limit of the one-loop calculation about a de Sitter background does not change the results previously obtained in the literature, where the tree-level potential in flat space-time was studied. Moreover, when curvature effects are no longer negligible in the one-loop potential, it is found that the early universe remains bound to reach only the SO(6)xSO(4) absolute minimum.Comment: 25 pages, plain Tex, plus Latex file of the tables appended at the end. Published in Classical and Quantum Gravity, Vol. 11, pp. 2031-2044, August 199

    Generation and Characterization of a Tumor Stromal Microenvironment and Analysis of Its Interplay with Breast Cancer Cells: An In Vitro Model to Study Breast Cancer-Associated Fibroblast Inactivation

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    Breast cancer-associated fibroblasts (BCAFs), the most abundant non-cancer stromal cells of the breast tumor microenvironment (TME), dramatically sustain breast cancer (BC) progression by interacting with BC cells. BCAFs, as well as myofibroblasts, display an up regulation of activation and inflammation markers represented by α-smooth muscle actin (α-SMA) and cyclooxygenase 2 (COX-2). BCAF aggregates have been identified in the peripheral blood of metastatic BC patients. We generated an in vitro stromal model consisting of human primary BCAFs grown as monolayers or 3D cell aggregates, namely spheroids and reverted BCAFs, obtained from BCAF spheroids reverted to 2D cell adhesion growth after 216 h of 3D culture. We firstly evaluated the state of activation and inflammation and the mesenchymal status of the BCAF monolayers, BCAF spheroids and reverted BCAFs. Then, we analyzed the MCF-7 cell viability and migration following treatment with conditioned media from the different BCAF cultures. After 216 h of 3D culture, the BCAFs acquired an inactivated phenotype, associated with a significant reduction in α-SMA and COX-2 protein expression. The deactivation of the BCAF spheroids at 216 h was further confirmed by the cytostatic effect exerted by their conditioned medium on MCF-7 cells. Interestingly, the reverted BCAFs also retained a less activated phenotype as indicated by α-SMA protein expression reduction. Furthermore, the reverted BCAFs exhibited a reduced pro-tumor phenotype as indicated by the anti-migratory effect exerted by their conditioned medium on MCF-7 cells. The deactivation of BCAFs without drug treatment is possible and leads to a reduced capability of BCAFs to sustain BC progression in vitro. Consequently, this study could be a starting point to develop new therapeutic strategies targeting BCAFs and their interactions with cancer cells

    Post-operative acute urinary retention after greenlight laser. Analysis of risk factors from a multicentric database

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    Purpose: Greenlight laser is a mini-invasive technique used to treat Benign Prostatic Obstruction (BPO). Some of the advantages of GreenLight photoselective vaporization (PVP) are shorter catheterization time and hospital stay compared to TURP. Post-operative acute urinary retention (pAUR) leads to patients' discomfort, prolonged hospital stay and increased health care costs. We analyzed risk factors for urinary retention after GreenLight laser PVP. Materials and methods: In a multicenter experience, we retrospectively analyzed the onset of early and late post-operative acute urinary retention in patients undergoing standard or anatomical PVP. The pre-, intra- and post-operative characteristics were compared betweene patients who started to void and the patients who developed post-operative urinary retention. Results: The study included 434 patients suitable for the study. Post-operative acute urinary retention occurred in 39 (9%). Patients with a lower prostate volume (P < .001), an adenoma volume lower than 40 mL (P < .001), and lower lasing time (P = .013) had a higher probability to develop pAUR at the univariate analysis. The multivariate logistic regression confirmed that lower lasing time (95% CI: 0.86-0.99, OR = 0.93, P = .046) and adenoma volume (95% CI: 0.89-0.98, OR = 0.94, P = .006) are correlated to pAUR. Furthermore IPSS ≥ 19 (95% CI: 1.19- 10.75, OR = 2.27, P = .023) and treatment with 5-ARI (95% CI: 1.05-15.03, OR = 3.98, P = .042) are risk factors for pAUR. Conclusion: In our series, post-operative acute urinary retention was related to low adenoma volume and lasing time, pre-operative IPSS ≥ 19 and 5-ARI intake. These data should be considered in deciding the best timing for urethral catheters removal

    The SURPRISE demonstrator: a super-resolved compressive instrument in the visible and medium infrared for Earth Observation

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    While Earth Observation (EO) data has become ever more vital to understanding the planet and addressing societal challenges, applications are still limited by revisit time and spatial resolution. Though low Earth orbit missions can achieve resolutions better than 100 m, their revisit time typically stands at several days, limiting capacity to monitor dynamic events. Geostationary (GEO) missions instead typically provide data on an hour-basis but with spatial resolution limited to 1 km, which is insufficient to understand local phenomena. In this paper, we present the SURPRISE project - recently funded in the frame of the H2020 programme – that gathers the expertise from eight partners across Europe to implement a demonstrator of a super-spectral EO payload - working in the visible (VIS) - Near Infrared (NIR) and in the Medium InfraRed (MIR) and conceived to operate from GEO platform -with enhanced performance in terms of at-ground spatial resolution, and featuring innovative on-board data processing and encryption functionalities. This goal will be achieved by using Compressive Sensing (CS) technology implemented via Spatial Light Modulators (SLM). SLM-based CS technology will be used to devise a super-resolution configuration that will be exploited to increase the at-ground spatial resolution of the payload, without increasing the number of detector’s sensing elements at the image plane. The CS approach will offer further advantages for handling large amounts of data, as is the case of superspectral payloads with wide spectral and spatial coverage. It will enable fast on-board processing of acquired data for information extraction, as well as native data encryption on top of native compression. SURPRISE develops two disruptive technologies: Compressive Sensing (CS) and Spatial Light Modulator (SLM). CS optimises data acquisition (e.g. reduced storage and transmission bandwidth requirements) and enables novel onboard processing and encryption functionalities. SLM here implements the CS paradigm and achieves a super-resolution architecture. SLM technology, at the core of the CS architecture, is addressed by: reworking and testing off-the-shelf parts in relevant environment; developing roadmap for a European SLM, micromirror array-type, with electronics suitable for space qualification. By introducing for the first time the concept of a payload with medium spatial resolution (few hundreds of meters) and near continuous revisit (hourly), SURPRISE can lead to a EO major breakthrough and complement existing operational services. CS will address the challenge of large data collection, whilst onboard processing will improve timeliness, shortening time needed to extract information from images and possibly generate alarms. Impact is relevant to industrial competitiveness, with potential for market penetration of the demonstrator and its components

    Associations between depressive symptoms and disease progression in older patients with chronic kidney disease: results of the EQUAL study

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    Background Depressive symptoms are associated with adverse clinical outcomes in patients with end-stage kidney disease; however, few small studies have examined this association in patients with earlier phases of chronic kidney disease (CKD). We studied associations between baseline depressive symptoms and clinical outcomes in older patients with advanced CKD and examined whether these associations differed depending on sex. Methods CKD patients (>= 65 years; estimated glomerular filtration rate <= 20 mL/min/1.73 m(2)) were included from a European multicentre prospective cohort between 2012 and 2019. Depressive symptoms were measured by the five-item Mental Health Inventory (cut-off <= 70; 0-100 scale). Cox proportional hazard analysis was used to study associations between depressive symptoms and time to dialysis initiation, all-cause mortality and these outcomes combined. A joint model was used to study the association between depressive symptoms and kidney function over time. Analyses were adjusted for potential baseline confounders. Results Overall kidney function decline in 1326 patients was -0.12 mL/min/1.73 m(2)/month. A total of 515 patients showed depressive symptoms. No significant association was found between depressive symptoms and kidney function over time (P = 0.08). Unlike women, men with depressive symptoms had an increased mortality rate compared with those without symptoms [adjusted hazard ratio 1.41 (95% confidence interval 1.03-1.93)]. Depressive symptoms were not significantly associated with a higher hazard of dialysis initiation, or with the combined outcome (i.e. dialysis initiation and all-cause mortality). Conclusions There was no significant association between depressive symptoms at baseline and decline in kidney function over time in older patients with advanced CKD. Depressive symptoms at baseline were associated with a higher mortality rate in men

    Understanding Factors Associated With Psychomotor Subtypes of Delirium in Older Inpatients With Dementia

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    Numerical evaluation of finite length tubes effects in Stirling engines heaters

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    The performance of Stirling engines is directly related to the amount of energy that, in the form of heat, participates in the thermodynamic cycle. A peculiar characteristic of this type of engine is the closed circuit of the working fluid, implying a periodic admission and extraction, ideally involving the whole working fluid, of the heat exchanged during the cycle without any exchange of material with the external environment. Several correlations have been proposed in the literature to predict the heat exchange in the hot side heat exchangers, but most of them are based on nondimensional numbers, usually expressed in terms of an oscillatory Reynolds number and a non-dimensional length, that even if they take into account the amplitude and frequency of the oscillating flow inside the tube with respect to its diameter, do not include any dependency upon the length of the tube. Nevertheless, the length of the tube can have a great impact on the performance of a Stirling engine. The heater forms a significant part of the dead volume of the engine, making the optimization of the volume to surface ratio necessary. The friction losses increase by increasing the length of the tubes, determining a negative impact while the exchange surface increases. Even the Nusselt number in the inner side of the tubes changes along the length, achieving the largest values alternatively in the first portions of the tube lengths because of entrance effects (Graetz problem). The picture is made even more complex because of the special velocity profiles that develop in oscillating flows in tubes. One of the effects less investigated in previous studies, which we could call a “breathing effect”, regards the amount of working fluid that, in a real engine, can effectively travel from the hot side to the cold side, thus reaching the conditions of nominal heat exchange with the thermal source and sink of the cycle. An idealized configuration has been devised to investigate, using CFD simulations, these effects. Results reporting how the friction coefficient and the Nusselt number depend on the finite length of the tube will be illustrated
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