92 research outputs found

    Techno-economic analysis of a sCO2 power plant for waste heat recovery in steel industry

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    Abstract Industrial facilities release a large amount of heat as a by-product of their processes. To improve environmental performance and increase process profitability, a portion of the waste heat can be recovered and employed for power generation by recovery systems. Supercritical carbon dioxide (sCO2) plants are emerging as potential alternatives to the well-established technologies for waste heat recovery (WHR) power generation in heavy industry. This paper offers a preliminary techno-economic analysis of a waste heat-to-power system based on a sCO2 closed-loop for a heavy-industrial process. By conducting a parametric investigation on the WHR sCO2 system's key design parameters, a number of preferable configurations from a thermodynamic perspective were initially identified; they were subsequently analyzed from the economic point of view in terms of net present value (NPV) and pay-back period (PBP). The privileged WHR system configuration achieved an overall efficiency of 30.4% and a power output of 21.6 kWe, providing an NPV of almost US k$ 376 with a PBP of approximately 4.5 years

    CYP1A1 Variability In Human Populations

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    The human cytochrome P4501A1 (CYP1A1) enzyme plays an important role in the metabolism of xenobiotics and endogenous substrates. Because polymorphisms within the CYP1A1 gene have been shown to be associated with various cancer risks and with the predicting clinical efficacy of some chemotherapies in different populations, most studies focus on their clinical significance. We, however, were interested in evaluating whether the polymorphisms could be used to distinguish human populations. Four single nucleotide CYP1A1 polymorphisms (rs4646903/ g.75011641; rs1048943/g.75012985; g.75012235; and rs1799814/ g.75012987) were analysed via PCR-RFLP assay in 1,195 individuals of various human groups from all over the world. In order to gain a more complete view of the genetic variability of the CYP1A1 gene, different statistical analyses were performed upon the populations of the present study and upon the limited data gleaned from previously studied populations. The allele and haplotype frequencies vary among populations: the rs4646903 (C) and rs1048943 (G) have been found to be nearly always linked and were found at the highest frequencies in Native Americans, while the variant associated to the position g.75012235 was only detected in certain African populations. Our work clearly indicates that the CYP1A1 polymorphisms differ among populations and that the prediction of genotypes constitutes an important aspect of precision medicine since some variants were associated with certain cancers and rs1048943 show strong association with optimized chemotherapy. Moreover, the CYP1A1 gene plays an important role in the metabolism of xenobiotics and it is likely that its frequencies could be strongly influenced by environmental factors

    Long-term exposure of pancreatic β-cells to palmitate results in SREBP-1C-dependent decreases in GLP-1 receptor signaling via CREB and AKT and insulin secretory response

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    The effects of prolonged exposure of pancreatic β-cells to high saturated fatty acids on glucagonlike peptide-1 (GLP-1) action were investigated. Murine islets, human pancreatic 1.1B4 cells, and rat INS-1E cells were exposed to palmitate for 24 hours. mRNA and protein expression/phosphorylation were measured by real-time RT-PCR and immunoblotting, respectively. Specific short interfering RNAs were used to knockdown expression of the GLP-1 receptor (Glp1r) and Srebf1. Insulin release was assessed with a specific ELISA. Exposure of murine islets, as well as of human and INS-1E β-cells, to palmitate reduced the ability of exendin-4 to augment insulin mRNA levels, protein content, and release. In addition, palmitate blocked exendin-4-stimulated cAMP-response element-binding protein and v-akt murine thymoma viral oncogene homolog phosphorylation, whereas phosphorylation of MAPK-ERK kinase-1/2 and ERK-1/2 was not altered. Similarly, RNA interference-mediated suppression of Glp1r expression prevented exendin-4-induced cAMP-response element-binding protein and v-akt murine thymoma viral oncogene homolog phosphorylation, but did not impair exendin-4 stimulation of MAPK-ERK kinase-1/2 and ERK-1/2. Both islets from mice fed a high fat diet and human and INS-1E β-cells exposed to palmitate showed reduced GLP-1 receptor and pancreatic duodenal homeobox-1 (PDX-1) and increased sterol regulatory element-binding protein (SREBP-1C) mRNA and protein levels. Furthermore, suppression of SREBP-1C protein expression prevented the reduction of PDX-1 and GLP-1 receptor levels and restored exendin-4 signaling and action. Finally, treatment of INS-1E cells with metformin for 24 h resulted in inhibition of SREBP-1C expression, increased PDX-1 and GLP-1 receptor levels, consequently, enhancement of exendin-4-induced insulin release. Palmitate impairs exendin-4 effects on β-cells by reducing PDX-1 and GLP-1 receptor expression and signaling inaSREBP-1C-dependent manner. Metformin counteracts the impairment of GLP-1 receptor signaling induced by palmitate

    The effects of psychoeducational family intervention on coping strategies of relatives of patients with bipolar i disorder: Results from a controlled, real-world, multicentric study

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    Background: Psychoeducational family intervention (PFI) has been proven to be effective in improving the levels of family burden and patients\u2019 personal functioning in schizophrenia and bipolar disorders (BDs). Less is known about the impact of PFI on relatives\u2019 coping strategies in BD. Methods: A multicenter, controlled, outpatient trial funded by the Italian Ministry of Health and coordinated by the Department of Psychiatry of the University of Campania \u201cLuigi Vanvitelli\u201d has been conducted in patients with bipolar I disorder (BD-I) and their key relatives consecutively recruited in 11 randomly selected Italian community mental health centers. We aim to test the hypothesis that PFI improves problem-oriented coping strategies in relatives of BD-I patients compared to the Treatment As Usual (TAU) group. Results: The final sample was constituted of 123 patients and 139 relatives. At baseline assessment (T0), the vast majority of relatives already adopted problem-oriented coping strategies more frequently than the emotion-focused ones. At the end of the intervention, relatives receiving PFI reported a higher endorsement of adaptive coping strategies, such as \u201cmaintenance of social interests\u201d (odds ratio [OR]=0.309, CI=0.04\u20130.57; p=0.023), \u201cpositive communication with the patient\u201d (OR=0.295, CI=0.13\u20130.46; p=0.001), and \u201csearching for information\u201d (OR=0.443, CI=0.12\u20130.76; p=0.007), compared to TAU relatives, after controlling for several confounders. As regards the emotion-focused coping strategies, relatives receiving the experimental intervention less frequently reported to adopt \u201cresignation\u201d (OR=-0.380, CI=-0.68 to -0.08; p=0.014) and \u201ccoercion\u201d (OR=-0.268, CI=-0.46 to -0.08; p=0.006) strategies, compared to TAU relatives. Conclusion: PFI is effective in improving the adaptive coping strategies of relatives of BD-I patients, but further studies are needed for evaluating the long-term benefits of this intervention

    The DICA Endoscopic Classification for Diverticular Disease of the Colon Shows a Significant Interobserver Agreement among Community Endoscopists: an International Study

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    Background & Aims: The Diverticular Inflammation and Complication Assessment (DICA) endoscopic classification of diverticulosis and diverticular disease (DD) is currently available. It scores severity of the disease as DICA 1, DICA 2 and DICA 3. Our aim was to assess the agreement on this classification in an international endoscopists community setting. Methods: A total of 96 doctors (82.9% endoscopists) independently scored a set of DD endoscopic videos. The percentages of overall agreement on DICA score and a free-marginal multirater kappa (kappa) coefficient were reported as statistical measures of interrater agreement. Results: Overall agreement in using DICA was 91.8% with a free-marginal kappa of 88% (95% CI 80-95). The overall agreement levels were: DICA 1, 85.2%; DICA 2, 96.5%; DICA 3, 99.5%. The free marginal. was: DICA 1 = 0.753, DICA 2 = 0.958, DICA 3 = 0.919. The agreement about the main endoscopic items was 83.4% (k 67%) for diverticular extension, 62.6% (k 65%) for number of diverticula for each district, 86.8% (k 82%) for presence of inflammation, and 98.5 (k 98%) for presence of complications. Conclusions: The overall interrater agreement in this study ranges from good to very good. DICA score is a simple and reproducible endoscopic scoring system for diverticulosis and DD

    FOOT: a new experiment to measure nuclear fragmentation at intermediate energies

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    Summary: Charged particle therapy exploits proton or 12C beams to treat deep-seated solid tumors. Due to the advantageous characteristics of charged particles energy deposition in matter, the maximum of the dose is released to the tumor at the end of the beam range, in the Bragg peak region. However, the beam nuclear interactions with the patient tissues induces fragmentation both of projectile and target nuclei and needs to be carefully taken into account. In proton treatments, target fragmentation produces low energy, short range fragments along all the beam range, which deposit a non negligible dose in the entry channel. In 12C treatments the main concern is represented by long range fragments due to beam fragmentation that release their dose in the healthy tissues beyond the tumor. The FOOT experiment (FragmentatiOn Of Target) of INFN is designed to study these processes, in order to improve the nuclear fragmentation description in next generation Treatment Planning Systems and the treatment plans quality. Target (16O and 12C nuclei) fragmentation induced by –proton beams at therapeutic energies will be studied via an inverse kinematic approach, where 16O and 12C therapeutic beams impinge on graphite and hydrocarbon targets to provide the nuclear fragmentation cross section on hydrogen. Projectile fragmentation of 16O and 12C beams will be explored as well. The FOOT detector includes a magnetic spectrometer for the fragments momentum measurement, a plastic scintillator for ΔE and time of flight measurements and a crystal calorimeter to measure the fragments kinetic energy. These measurements will be combined in order to make an accurate fragment charge and isotopic identification. Keywords: Hadrontherapy, Nuclear fragmentation cross sections, Tracking detectors, Scintillating detector

    Mitochondrial Haplogroup H1 in North Africa: An Early Holocene Arrival from Iberia

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    The Tuareg of the Fezzan region (Libya) are characterized by an extremely high frequency (61%) of haplogroup H1, a mitochondrial DNA (mtDNA) haplogroup that is common in all Western European populations. To define how and when H1 spread from Europe to North Africa up to the Central Sahara, in Fezzan, we investigated the complete mitochondrial genomes of eleven Libyan Tuareg belonging to H1. Coalescence time estimates suggest an arrival of the European H1 mtDNAs at about 8,000–9,000 years ago, while phylogenetic analyses reveal three novel H1 branches, termed H1v, H1w and H1x, which appear to be specific for North African populations, but whose frequencies can be extremely different even in relatively close Tuareg villages. Overall, these findings support the scenario of an arrival of haplogroup H1 in North Africa from Iberia at the beginning of the Holocene, as a consequence of the improvement in climate conditions after the Younger Dryas cold snap, followed by in situ formation of local H1 sub-haplogroups. This process of autochthonous differentiation continues in the Libyan Tuareg who, probably due to isolation and recent founder events, are characterized by village-specific maternal mtDNA lineages
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