146 research outputs found

    Off-the-shelf solvers for mixed-integer conic programming: insights from a computational study on congested capacitated facility location instances

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    This paper analyzes the performance of five well-known off-the-shelf optimization solvers on a set of mixed-integer conic programs proposed for the congested capacitated facility location problem. We aim to compare the computational efficiency of the solvers and examine the solution strategies they adopt when solving instances with different sizes and complexity. The solvers we compare are Gurobi, Cplex, Mosek, Xpress, and Scip. We run extensive numerical tests on a testbed of 30 instances from the literature. Our results show that Mosek and Gurobi are the most competitive solvers, as they achieve better time and gap performance, solving most instances within the time limit. Mosek outperforms Gurobi in large-size problems and provides more accurate solutions in terms of feasibility. Xpress solves to optimality about half of the instances tested within the time limit, and in this half, it achieves performance similar to that of Gurobi and Mosek. Cplex and Scip emerge as the least competitive solvers. The results provide guidelines on how each solver behaves on this class of problems and highlight the importance of choosing a solver suited to the problem type

    Chapter Il disegno delle gemme sfaccettate. Fonti iconografiche e trattatistica, analisi geometrica, rilevamento, modellazione parametrica

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    The 43rd UID conference, held in Genova, takes up the theme of ‘Dialogues’ as practice and debate on many fundamental topics in our social life, especially in these complex and not yet resolved times. The city of Genova offers the opportunity to ponder on the value of comparison and on the possibilities for the community, naturally focused on the aspects that concern us, as professors, researchers, disseminators of knowledge, or on all the possibile meanings of the discipline of representation and its dialogue with ‘others’, which we have broadly catalogued in three macro areas: History, Semiotics, Science / Technology. Therefore, “dialogue” as a profitable exchange based on a common language, without which it is impossible to comprehend and understand one another; and the graphic sign that connotes the conference is the precise transcription of this concept: the title ‘translated’ into signs, derived from the visual alphabet designed for the visual identity of the UID since 2017. There are many topics which refer to three macro sessions: - Witnessing (signs and history) - Communicating (signs and semiotics) - Experimenting (signs and sciences) Thanks to the different points of view, an exceptional resource of our disciplinary area, we want to try to outline the prevailing theoretical-operational synergies, the collaborative lines of an instrumental nature, the recent updates of the repertoires of images that attest and nourish the relations among representation, history, semiotics, sciences

    Power Reduction in FM Networks by Mixed-Integer Programming. A Case Study

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    The climate change emergency calls for a reduction in energy consumption in all human activities and production processes. The radio broadcasting industry is no exception. However, reducing energy requirements by uniformly cutting the radiated power at every transmitter can potentially impair the quality of service. A careful evaluation and optimization study are in order. In this paper, by analyzing the Italian frequency modulation analog broadcasting service, we show that it is indeed possible to significantly reduce the energy consumption of the broadcasters without sacrificing the quality of the service, rather, even getting improvements

    Significance of serum Myostatin in hemodialysis patients

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    Background: Malnutrition and muscle wasting are common in haemodialysis (HD) patients. Their pathogenesis is complex and involves many molecules including Myostatin (Mstn), which acts as a negative regulator of skeletal muscle. The characterisation of Mstn as a biomarker of malnutrition could be useful in the prevention and management of this condition. Previous studies have reported no conclusive results on the actual relationship between serum Mstn and wasting and malnutrition. So, in this study, we evaluated Mstn profile in a cohort of regular HD patients. Methods: We performed a cross-sectional study, enrolling 37 patients undergoing bicarbonate-HD (BHD) or haemodiafiltration (HDF) at least for six months. 20 sex-matched healthy subjects comprised the control group. Mstn serum levels were evaluated by ELISA before and after HD. We collected clinical and biochemical data, evaluated insulin resistance, body composition, malnutrition [by Malnutrition Inflammation Score (MIS)] and tested muscle function (by hand-grip strength, six-minute walking test and a questionnaire on fatigue). Results: Mstn levels were not significantly different between HD patients and controls (4.7 \ub1 2.8 vs 4.5 \ub1 1.3 ng/ml). In addition, while a decrease in Mstn was observed after HD treatment, there were no differences between BHD and HDF. In whole group of HD patients Mstn was positively correlated with muscle mass (r = 0.82, p < 0.001) and inversely correlated with age (r = - 0.63, p < 0.01) and MIS (r = - 0.39, p = 0.01). No correlations were found between Mstn and insulin resistance, such as between Mstn levels and parameters of muscle strength and fatigue. In multivariate analysis, Mstn resulted inversely correlated with fat body content (\u3b2 = - 1.055, p = 0.002). Conclusions: Circulating Mstn is related to muscle mass and nutritional status in HD patients, suggesting that it may have a role in the regulation of skeletal muscle and metabolic processes. However, also considering the lack of difference of serum Mstn between healthy controls and HD patients and the absence of correlations with muscle function tests, our findings do not support the use of circulating Mstn as a biomarker of muscle wasting and malnutrition in HD

    Evidence from Family Studies for Autoimmunity in Arrhythmogenic Right Ventricular Cardiomyopathy: Associations of Circulating Anti-Heart and Anti-Intercalated Disk Autoantibodies with Disease Severity and Family History

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    Background: Serum anti-heart autoantibodies (AHA) and anti-intercalated disk autoantibodies (AIDA) are autoimmune markers in myocarditis. In arrhythmogenic right ventricular cardiomyopathy (ARVC) myocarditis has been reported. To provide evidence for autoimmunity, we searched for AHA and AIDA in ARVC. Methods: We studied: 42 ARVC probands, 23 male, aged 42, interquartile range (IQR) 33;49, 20 from familial and 22 non-familial pedigrees; 37 clinically affected relatives (AR), 24 male aged 35, IQR 18;46; 96 healthy relatives (HR), 49 male, aged 27, IQR 17;45. Serum AHA and AIDA were tested by indirect immunofluorescence on human myocardium and skeletal muscle in 171 of the 175 ARVC individuals and in controls with: non-inflammatory cardiac disease (NICD) (n=160), ischemic heart failure (IHF) (n=141), normal blood donors (NBD) (n=270). Screening of five desmosomal genes was performed in probands; when a sequence variant was identified, cascade family screening followed, blind to immunological results. Results: AHA frequency was higher (36.8%) in probands, AR (37.8%) and HR (25%) than in NICD (1%), IHF (1%) or NBD (2.5%) (p=0.0001). AIDA frequency was higher in probands (8%, p=0.006), in AR (21.6%, p=0.00001) and in HR (14.6% p=0.00001) than in NICD (3.75%), IHF (2%) or NBD (0.3%). AHA positive status was associated with higher frequency of palpitation (p=0.004), ICD implantation (p=0.021), lower left ventricular ejection fraction (LVEF) (p=0.004), AIDA positive status with both lower RV and LVEF (p=0.027 and p=0.027 respectively). AHA and/or AIDA positive status in the proband and/or at least one of the respective relatives was more common in familial (17/20, 85%) than in sporadic (10/22, 45%) pedigrees (p=0.007). Conclusions: Presence of AHA and AIDA provides evidence of autoimmunity in the majority of familial and in almost half of sporadic ARVC. In probands and in AR these antibodies were associated with disease severity features; longitudinal studies are needed to clarify whether they may predict ARVC development in HR or if they be a result of manifest ARVC

    The role of superior hemorrhoidal vein ectasia in the preoperative staging of rectal cancer

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    ObjectiveThe prognosis of colorectal cancer has continuously improved in recent years thanks to continuous progress in both the therapeutic and diagnostic fields. The specific objective of this study is to contribute to the diagnostic field through the evaluation of the correlation between superior hemorrhoidal vein (SHV) ectasia detected on computed tomography (CT) and Tumor (T), Node (N), and distant metastasis (M) examination and mesorectal fascia (MRF) invasion in the preoperative staging of rectal cancer.MethodsBetween January 2018 and April 2022, 46 patients with histopathological diagnosis of rectal cancer were retrospectively enrolled, and the diameter of the SHV was evaluated by CT examination. The cutoff value for SHV diameter used is 3.7 mm. The diameter was measured at the level of S2 during portal venous phase after 4× image zoom to reduce the interobserver variability. The parameters evaluated were tumor location, detection of MRF infiltration (defined as the distance < 1 mm between the tumor margins and the fascia), SHV diameter, detection of mesorectal perilesional lymph nodes, and detection of metastasis.ResultsA total of 67.39% (31/46) of patients had SHV ectasia. All patients with MRF infiltration (4/46, 7.14%) presented SHV ectasia (average diameter of 4.4 mm), and SHV was significantly related with the development of liver metastases at the moment of primary staging and during follow-up.ConclusionSHV ectasia may be related to metastasis and MRF involvement; therefore, it could become a tool for preoperative staging of rectal cancer

    Bi-allelic genetic variants in the translational GTPases GTPBP1 and GTPBP2 cause a distinct identical neurodevelopmental syndrome

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    : The homologous genes GTPBP1 and GTPBP2 encode GTP-binding proteins 1 and 2, which are involved in ribosomal homeostasis. Pathogenic variants in GTPBP2 were recently shown to be an ultra-rare cause of neurodegenerative or neurodevelopmental disorders (NDDs). Until now, no human phenotype has been linked to GTPBP1. Here, we describe individuals carrying bi-allelic GTPBP1 variants that display an identical phenotype with GTPBP2 and characterize the overall spectrum of GTP-binding protein (1/2)-related disorders. In this study, 20 individuals from 16 families with distinct NDDs and syndromic facial features were investigated by whole-exome (WES) or whole-genome (WGS) sequencing. To assess the functional impact of the identified genetic variants, semi-quantitative PCR, western blot, and ribosome profiling assays were performed in fibroblasts from affected individuals. We also investigated the effect of reducing expression of CG2017, an ortholog of human GTPBP1/2, in the fruit fly Drosophila melanogaster. Individuals with bi-allelic GTPBP1 or GTPBP2 variants presented with microcephaly, profound neurodevelopmental impairment, pathognomonic craniofacial features, and ectodermal defects. Abnormal vision and/or hearing, progressive spasticity, choreoathetoid movements, refractory epilepsy, and brain atrophy were part of the core phenotype of this syndrome. Cell line studies identified a loss-of-function (LoF) impact of the disease-associated variants but no significant abnormalities on ribosome profiling. Reduced expression of CG2017 isoforms was associated with locomotor impairment in Drosophila. In conclusion, bi-allelic GTPBP1 and GTPBP2 LoF variants cause an identical, distinct neurodevelopmental syndrome. Mutant CG2017 knockout flies display motor impairment, highlighting the conserved role for GTP-binding proteins in CNS development across species
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