208 research outputs found

    Verification of Planetary Protection Requirements with Symplectic Methods and Monte Carlo Line Sampling

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    Verification of the compliance to planetary protection requirements is an important task of interplanetary mission design, aiming to reduce the risk of biological contamination of scientifically interesting celestial bodies. This kind of analysis requires efficient and reliable numerical tools to propagate uncertainties over times up to 100 years with high precision. This paper presents a plan to improve the techniques used for planetary protection analysis in the SNAPPshot numerical tool developed at the University of Southampton for an ESA study. The Line Sampling method is presented as an alternative Monte Carlo approach to sample more efficiently the initial uncertainties, reducing the computational effort to estimate the probability of impact between uncontrolled objects and a celestial body. Symplectic integration methods are introduced as a strategy to obtain a more accurate propagation of the spacecraft trajectory starting from the initial conditions, thanks to their formulation that includes the conservation of total energy. Preliminary results are included to show the advantages and the current limitations of the proposed approaches

    Impact probability computation of Near-Earth Objects using Monte Carlo Line Sampling and Subset Simulation

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    This work introduces two Monte Carlo (MC)-based sampling methods, known as line sampling and subset simulation, to improve the performance of standard MC analyses in the context of asteroid impact risk assessment. Both techniques sample the initial uncertainty region in different ways, with the result of either providing a more accurate estimate of the impact probability or reducing the number of required samples during the simulation with respect to standard MC techniques. The two methods are first described and then applied to some test cases, providing evidence of the increased accuracy or the reduced computational burden with respect to a standard MC simulation. Finally, a sensitivity analysis is carried out to show how parameter setting affects the accuracy of the results and the numerical efficiency of the two methods

    AttualitĂ  ed opportunitĂ  delle alternative al carcere fra diffidenze e risorse del territorio

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    In a period in which the only answer at crime and insecurity of citiziens is prison we wanted to follow historic steps that have carried at the building of prisons (from Middle Ages to XX century) asking us about their actuality and efficiency. In particulary the Authors have examinated an aspect of penal execution that is often forgotten or negletted but, in our opinion, it must be made stronger: alternative measures to prison. We have made a legislative analysis from the Law 354/1975 to the Law Gozzini to understand, with words of its Author, the spirit which carried to the introduction of an alternative street to prison. “Fathers” of this law have understood that if a person is part of the society also when he/she committed a crime – instead of staying in prison doing nothing – there are few possibilities that he/she will break the law again. Even if statistic numbers about alternative measures are positive, people are strongly disinformed about theirs effects. At all levels: from lawer to housewife, from policemen to teacher. And can we allow that with the apology of a low information prison becomes the only possibility to fight crime? As we can see from questionnaires we have handed out, also the distortion of reality on this topic is a known point, but not for this reason must be unchangeable too!In un momento storico in cui l'unica risposta possibile al reato e alla sensazione di insicurezza dei cittadini sembra essere il carcere, gli Autori hanno voluto ripercorrere le fasi storiche che hanno portato alla affermazione degli istituti di pena (dal Medioevo ad oggi), interrogandosi sulla attualità ed (in)efficacia degli stessi. In particolare essi hanno analizzato un aspetto dell'esecuzione penale spesso tralasciato e che, invece, dovrebbe a parer loro essere potenziato: le misure alternative alla detenzione. Un'analisi legislativa per capire lo spirito che generò ed informò l'introduzione di una soluzione alternativa al carcere. La risposta è che non si trattò di uno slancio “buonista”. I “padri” di questa legge avevano compreso che se una persona non viene estromessa dal contesto sociale cui appartiene anche quando ha commesso un reato –anziché essere segregata passivamente in carcere - le possibilità che infranga nuovamente la legge sono quantomeno ridotte. Inoltre, nonostante dati statistici sulla positività delle misure alternative, nella popolazione a tutti i livelli è forte ed allarmante la disinformazione sugli effetti delle stesse: dall'avvocato alla casalinga, dal poliziotto all'insegnante, dallo studente di Giurisprudenza al carabiniere. Come risulta dai questionari che gli Autori hanno somministrato, anche la distorsione della realtà su questo tema è un dato certo. Una corretta azione informativa si impone pertanto quale utile strumento per contribuire allo sviluppo di una adeguata ed opportuna cultura della pena

    Importance of perforating vessels in nipple-sparing mastectomy. an anatomical description

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    BACKGROUND: Nipple-sparing mastectomy (NSM), understood as an oncologically valid procedure, is relatively new, and is an evolution of traditional mastectomy, particularly in relation to breast-conserving surgery. The anterior perforating branches are responsible for the cutaneous vascularization of the breast skin, and their preservation is a fundamental step to avoid possible postoperative necrosis. Therefore, evaluating the potential complications of cancer-related reconstructive surgical procedures such as NSM, both the distance of the tumoral lesion from the skin and the surgical incision site should be carefully considered. The preferred site of incision corresponds to the inframammary fold or possibly the periareolar area. METHODS: We retrospectively reviewed 113 patients who underwent NSM from January 2005 to October 2012 to evaluate skin complications. The anatomical study was performed by magnetic resonance imaging of the breast. RESULTS: Only one of the 113 women who had undergone a NSM procedure had total necrosis (0.9%) and six patients had partial necrosis (5.8%) of the nipple-areola complex

    Techno-economic study of chimneyless electric arc furnace plants for the coproduction of steel and of electricity, hydrogen, or methanol

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    Electric arc furnace (EAF) is the most common technology for steel production from steel scrap. Although the input energy is mostly constituted by electricity, significant amounts of carbon dioxide are emitted with the exhaust gases, most of which are classifiable as process-related. The main goal of this study is to perform a techno-economic analysis of chimneyless electric arc furnace plants, fed by either scrap or direct reduced iron (DRI), and able to coproduce steel as well as electricity, hydrogen, or methanol. Several plant configurations are investigated, featuring different combinations of oxy-postcombustion, carbon capture, carbon monoxide-rich gas recovery, hydrogen or syngas production by high-temperature electrolysis or coelectrolysis, and methanol synthesis. These configurations are also characterized by decreased false air leakage and by heat recovery for steam production. Results show that all cases allow achieving a substantial reduction of direct carbon dioxide emissions, close to 99% compared to the unabated conditions. From an economic perspective, in a long-term scenario, the internal rate of return is always above 8%, and up to 73% for the DRI-fed case. However, in a short-term scenario, only cases with sole power production are economically viable. Hydrogen and methanol are competitive with market prices only for low electricity costs. In a higher electricity cost scenario, the case of carbon capture and storage is more competitive than the case of carbon capture and utilization. With an electricity cost of 100 €/MWh, a steel premium of 10-40 €/t allows to reach economic feasibility if methanol or hydrogen selling prices are in line with current market conditions. In general, the configurations with DRI-fed furnaces obtain more favorable economic performance than scrap-fed ones. The competitiveness of sole electricity, hydrogen or methanol production configurations depends on the case study and on the future market prices

    Lipopolysaccharide and lipotheicoic acid differentially modulate epididymal cytokine and chemokine profiles and sperm parameters in experimental acute epididymitis

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    Bacterial infections are the most prevalent etiological factors of epididymitis, a commonly diagnosed inflammatory disease in the investigation of male infertility factors. The influence of early pathogenic mechanisms at play during bacterial epididymitis on reproductive outcomes is little understood. We report here that experimental epididymitis induced in rats by Gram-negative (LPS) and Gram-positive (LTA) bacterial products resulted in differential patterns of acute inflammation in the cauda epididymis. LPS elicited a strong inflammatory reaction, as reflected by upregulation of levels of mRNA for seven inflammatory mediators (Il1b, Tnf, Il6, Ifng, Il10, Nos2 and Nfkbia), and tissue concentration of six cytokines/chemokines (IL1A, IL1B, IL6, IL10, CXCL2 and CCL2) within the first 24 h post-treatment. Conversely, LTA induced downregulation of one (Nfkbia) and upregulation of six (Il1b, Il6, Nos2, Il4 Il10 and Ptgs1) inflammatory gene transcripts, whereas increased the tissue concentration of three cytokines/chemokines (IL10, CXCL2 and CCL2). The stronger acute inflammatory response induced by LPS correlated with a reduction of epididymal sperm count and transit time that occurred at 1, 7, and 15 days post-treatment. Our study provides evidence that early epididymal inflammatory signaling events to bacterial activators of innate immunity may contribute to the detrimental effects of epididymitis upon male fertility.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)CNPqSao Paulo Research Foundation (FAPESP)Pro-Reitoria de Pesquisa/UNESPUniv Fed Sao Paulo, Escola Paulista Med, Sect Expt Endocrinol, Dept Pharmacol, BR-04044020 Sao Paulo, SP, BrazilUniv Estadual Paulista, Dept Pharmacol, Inst Biosci Botucatu, Botucatu, SP, BrazilSci & Innovat Ctr Androl, Androsci, BR-03178200 Sao Paulo, SP, BrazilUniv Sao Paulo, Med Sch, Hosp Clin, Reprod Toxicol Unity,Dept Pathol, BR-01246903 Sao Paulo, SP, BrazilUniv Sao Paulo, Med Sch, Hosp Clin, Div Urol, BR-01246903 Sao Paulo, SP, BrazilState Univ Centro Oeste, Dept Pharm, BR-85040080 Guarapuava, PR, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Sect Expt Endocrinol, Dept Pharmacol, BR-04044020 Sao Paulo, SP, Brazil(CNPq)/CSF/BJT: 401718/2012-3CNPq: 479546/2013-4, 455450/2014-5, 308349/2010-5FAPESP: 2010/52711-0, 2015/08227-0Pro-Reitoria de Pesquisa/UNESP: 557Web of Scienc

    An aqueous olive leaf extract (OLE) ameliorates parameters of oxidative stress associated with lipid accumulation and induces lipophagy in human hepatic cells

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    Fatty liver is a disease characterized by a buildup of lipids in the liver, often resulting from excessive consumption of high-fat-containing foods. Fatty liver can degenerate, over time, into more severe forms of liver diseases, especially when oxidative stress occurs. Olive leaf extract (OLE) is a reliable source of polyphenols with antioxidant and hypolipidemic properties that have been successfully used in medicine, cosmetics, and pharmaceutical products. Using "green" solvents with minimal impact on the environment and human health, which simultaneously preserves the extract's beneficial properties, represents one of the major challenges of biomedical research. In the present study, we assayed the potential antioxidant and lipid-lowering effect of a "green" OLE obtained by a water ultrasound-assisted extraction procedure, on the human hepatic HuH7 cell line, treated with a high concentration of free fatty acids (FFA). We found that high FFA concentration induced lipid accumulation and oxidative stress, as measured by increased hydrogen peroxide levels. Moreover, the activity of antioxidant enzymes, catalase, superoxide dismutase, and glutathione peroxidase, was reduced upon FFA treatment. Coincubation of high FFA with OLE reduced lipid and H2O2 accumulation and increased the activity of peroxide-detoxifying enzymes. OLE ameliorated mitochondrial membrane potential, and hepatic parameters by restoring the expression of enzymes involved in insulin signaling and lipid metabolism. Electron microscopy revealed an increased autophagosome formation in both FFA- and FFA + OLE-treated cells. The study of the autophagic pathway indicated OLE's probable role in activating lipophagy

    Correlations between cortical gyrification and schizophrenia symptoms with and without comorbid hostility symptoms

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    Introduction: Interest in identifying the clinical implications of the neuropathophysiological background of schizophrenia is rising, including changes in cortical gyrification that may be due to neurodevelopmental abnormalities. Inpatients with schizophrenia can show abnormal gyrification of cortical regions correlated with the symptom severity. Methods: Our study included 36 patients that suffered an acute episode of schizophrenia and have undergone structural magnetic resonance imaging (MRI) to calculate the local gyrification index (LGI). Results: In the whole sample, the severity of symptoms significantly correlated with higher LGI in different cortical areas, including bilateral frontal, cingulate, parietal, temporal cortices, and right occipital cortex. Among these areas, patients with low hostility symptoms (LHS) compared to patients with high hostility symptoms (HHS) showed significantly lower LGI related to the severity of symptoms in bilateral frontal and temporal lobes. Discussion: The severity of psychopathology correlated with higher LGI in large portions of the cerebral cortex, possibly expressing abnormal neural development in schizophrenia. These findings could pave the way for further studies and future tailored diagnostic and therapeutic strategies
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