145 research outputs found

    An efficient composite membrane to improve the performance of PEM reversible fuel cells

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    The aim of this study is to develop composite Nafion/GO membranes, varying GO loading, to be used in a Unitized reversible fuel cell comparing its performance with the baseline Nafion. Water uptake, ion exchange capacity (IEC), tensile strength, and SEM (scanning electron microscope) analysis are discussed. The SEM analysis revealed how the GO is homogeneously disposed into the Nafion matrix. The addition of GO improves the membrane tensile strength while reducing the elongation ratio. Water uptake, IEC enhance with the increasing of GO content. Regarding fuel cell mode, the performance is analysed using a polarization curve on a MEA with an effective area of 9 cm2. The composite membrane demonstrated higher mechanical strength, enhanced water uptake so higher performance in fuel cell mode. Despite the power absorbed from the electrolysis is higher when using a composite membrane, the beneficial effect in FC mode resulted in a slightly higher round trip efficiency. The GO-Nafion membrane was not able to maintain its performance with increasing the operating time, so potentially leading to a lower lifetime than the Nafion bare

    Effects of 2012 Earthquake on the behavior of Ghirlandina tower in Modena

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    Collapse events, that occurred in the past (such as the Venice Bell Tower in 1902 and the Civic Tower in Pavia in 1989) claimed for the need to assess the long-term behavior of such monuments. A significant effort has been therefore devoted to clarify the reasons for these collapses after many centuries from the construction date. In addition, recent earthquakes in Italy have once again put into evidence the seismic vulnerability of the cultural heritage. To assess this aspect, in many cases the soil-structure interaction cannot be neglected. In this context, a simple but consistent framework for soil-structure interaction analysis is here presented with reference to a case history. It is discussed how the difference in the fundamental frequency observed during seismic events can be associated to non-linearity in soil response, leading to a rotational stiffness of the soil-foundation system consistent with the shear strain level derived from the seismic ground response analysis. Thereafter, the validated soil-structure interaction model has been used to define an equivalent SDOF model of the structure that explains the differential settlements suffered by the Ghirlandina tower in Modena during the 2012 seismic events as well as its behavior since those events

    Ovarian Strumal Carcinoid: Case Report, Systematic Literature Review and Pooled Analysis

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    Background: Ovarian strumal carcinoid is a rare tumor in which thyroid (struma) and carcinoid components coexist. The disease is generally considered to be a borderline malignancy, however, cases with metastatic disease have been described. No data in the literature are available to guide diagnosis and therapy. Methods: We performed a pooled analysis and a systematic review of histopathological-confirmed strumal carcinoid cases published in the literature using the following keywords: “strumal carcinoid of the ovary”, “strumal carcinoid case report”. A case of strumal carcinoid tumor diagnosed and followed-up at the Medical Oncology Unit of Spedali Civili (Brescia, Italy) was also described and included. Results: Sixty-six eligible publications were identified, providing data from one hundred and seventeen patients, plus a case diagnosed at our institution. At presentation, among the eighty-eight patients with symptomatic disease, 37% of patients suffered from abdominal distention and 49% from pain due to a growing abdominal tumor mass, 37% from constipation (peptide YY was analyzed in only nine of them, resulting above the physiologic range). Surgery was the primary therapy in 99% of the patients. Three patients had metastatic disease at diagnosis and five patients underwent recurrence after radical surgery. Histology at disease recurrence concerned the thyroid component in two patients, the carcinoid component in two patients, both histologies in one patient. Median disease-free survival and overall survival in this series were not attained. Conclusion: Strumal carcinoid of the ovary generally presents a benign behavior and surgery is curative in most cases. However, a small group of patients with this disease can undergo disease recurrence due to both the thyroid and the neuroendocrine (carcinoid) components. A follow-up in radically operated patients is therefore needed, particularly in those with a voluminous disease at diagnosis

    Clinical Prognostic Factors in Patients With Metastatic Adrenocortical Carcinoma Treated With Second Line Gemcitabine Plus Capecitabine Chemotherapy

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    Gemcitabine plus Capecitabine (Gem/Cape) is a frequently adopted second line chemotherapy for metastatic adrenocortical carcinoma (ACC), but only a minority of patients is destined to obtain a clinical benefit. The identification of baseline predictive factors of efficacy is relevant. We retrospectively analyzed clinical data from 50 consecutive patients with metastatic progressing ACC treated between 2011 and 2019. Patients received intravenous Gemcitabine and oral Capecitabine on a metronomic schedule. Previous mitotane therapy was maintained. Clinical benefit (partial response + stable disease) at 4 months was 30%, median progression-free survival (PFS) and disease-specific survival (DSS) from Gem/Cape start were 3 and 8 months, respectively. Among clinical variables evaluated before the start of Gem/Cape, presence of ECOG performance status ≥1 [HR 6.93 95% confidence interval (CI) 0.03–0.54, p.004] and neutrophil-to-lymphocyte ratio (NLR) ≥5 [HR 3.88, 95% (CI) 0.81–0.90, p.003] were independent indicators of poor PFS at multivariate analysis. Conversely, surgery of primary tumor, the presence of lung or lymph-node metastases, blood mitotane level, anemia, and the Advanced Lung cancer Inflammation index (ALI) failed to be independently associated. This study confirms that the Gem/Cape schedule is modestly active in heavily pretreated ACC patients (28% received at least two previous chemotherapy lines). NLR and performance status (PS) are easily available clinical parameters that are helpful to identify patients not likely to derive significant advantage from Gem/Cape chemotherapy

    Immune-related adverse events as potential surrogates of immune checkpoint inhibitors’ efficacy: a systematic review and meta-analysis of randomized studies

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    Background: Immune-related adverse events (irAEs) are frequently reported during immune checkpoint inhibitor (ICI) therapy and are associated with long-term outcomes. It is unknown if the irAE occurrence is a valid surrogate of ICIs’ efficacy. Methods: We identified articles reporting the results of randomized trials of experimental ICI therapy in solid tumors with a systematic search. The control arms could be placebo, cytotoxic/targeted therapy, or ICI therapy. We extracted the hazard ratios for overall survival (OS) with the number of OS events per arm and the number and percentages of overall and specific irAEs of grade 1-2 and grade 3-4 per arm. We estimated the treatment effect on the potential surrogate outcome with the odds ratio of the irAE rate between the experimental and the control arm. The statistical analysis consisted of weighted linear regression on a logarithmic scale between treatment effects on irAE rate and treatment effects on OS. Results: Sixty-two randomized trials were included for a total of 79 contrasts and 42 247 patients. The analyses found no significant association between the treatment effects for overall grade 1-2 or grade 3-4 irAE rates or specific (skin, gastrointestinal, endocrine) irAE rates. In the non-small-cell lung cancer (NSCLC) trial subset, we observed a negative association between treatment effects on overall grade 1-2 irAEs and treatment effects on OS in studies with patients selected for programmed death-ligand 1 expression (R2 = 0.55; 95% confidence interval 0.20-0.95; R = −0.69). In the melanoma trial subset, a negative association was shown between treatment effects on gastrointestinal grade 3-4 irAEs and treatment effects on OS in trials without an ICI-based control arm (R2 = 0.77; 95% confidence interval 0.24-0.99; R = −0.89). Conclusions: We found low-strength correlations between the ICI therapy effects on overall or specific irAE rates and the treatment effects on OS in several cancer types

    Sacituzumab govitecan and radiotherapy in metastatic, triple-negative, and BRCA-mutant breast cancer patient with active brain metastases: A case report

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    Background: Triple-negative breast cancer (TNBC) is an aggressive cancer subtype, owing to its high metastatic potential: Patients who develop brain metastases (BMs) have a poor prognosis due to the lack of effective systemic treatments. Surgery and radiation therapy are valid options, while pharmacotherapy still relies on systemic chemotherapy, which has limited efficacy. Among the new treatment strategies available, the antibody-drug conjugate (ADC) sacituzumab govitecan has shown an encouraging activity in metastatic TNBC, even in the presence of BMs. Case presentation: A 59-year-old woman was diagnosed with early TNBC and underwent surgery and subsequent adjuvant chemotherapy. A germline pathogenic variant in BReast CAncer gene 2 (BRCA2) was revealed after genetic testing. After 11 months from the completion of adjuvant treatment, she had pulmonary and hilar nodal relapse and began first-line chemotherapy with carboplatin and paclitaxel. However, after only 3 months from starting the treatment, she experienced relevant disease progression, due to the appearance of numerous and symptomatic BMs. Sacituzumab govitecan (10 mg/kg) was started as second-line treatment as part of the Expanded Access Program (EAP). She reported symptomatic relief after the first cycle and received whole-brain radiotherapy (WBRT) concomitantly to sacituzumab govitecan treatment. The subsequent CT scan showed an extracranial partial response and a near-to-complete intracranial response; no grade 3 adverse events were reported, even if sacituzumab govitecan was reduced to 7.5 mg/kg due to persistent G2 asthenia. After 10 months from starting sacituzumab govitecan, a systemic disease progression was documented, while intracranial response was maintained. Conclusions: This case report supports the potential efficacy and safety of sacituzumab govitecan in the treatment of early recurrent and BRCA-mutant TNBC. Despite the presence of active BMs, our patient had a progression-free survival (PFS) of 10 months in the second-line setting and sacituzumab govitecan was safe when administered together with radiation therapy. Further real-world data are warranted to confirm sacituzumab govitecan efficacy in this patient population

    Limits on Phase Separation for Two-Dimensional Strongly Correlated Electrons

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    From calculations of the high temperature series for the free energy of the two-dimensional t-J model we construct series for ratios of the free energy per hole. The ratios can be extrapolated very accurately to low temperatures and used to investigate phase separation. Our results confirm that phase separation occurs only for J/t greater than 1.2. Also, the phase transition into the phase separated state has Tc of approximately 0.25J for large J/t.Comment: 4 pages, 6 figure

    3D Engineering Geological Modeling to Investigate a Liquefaction Site: An Example in Alluvial Holocene Sediments in the Po Plain, Italy

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    Liquefaction-induced surface manifestations are the result of a complex geological–geotechnical phenomenon, driven by several controlling factors. We propose a multidisciplinary methodological approach, involving engineering geologists, geomorphologists, sedimentologists, and geotechnical engineers, to build a 3D engineering geological model for liquefaction assessment studies. The study area is Cavezzo (Po Plain, Italy), which is a municipality hit by superficial liquefaction manifestations during the Emilia seismic crisis of May–June 2012. The site is characterized by a Holocene alluvial sequence of the floodplain, fluvial channel, and crevasse splay deposits prone to liquefaction. The integration of different geotechnical investigations, such as boreholes, CPTm, CPTu, and laboratory tests, allowed us to recognize potentially liquefiable lithological units, crucial for hazard assessment studies. The resulting 3D engineering geological model reveals a strict correlation of co-seismic surface manifestations with buried silty sands and sandy silts within the shallow 10 m in fluvial channel setting, which is capped and laterally confined by clayey and silty deposits
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