155 research outputs found

    Corporate governance and performance: An analysis of Italian listed companies

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    In recent years, both corporate governance and performance management have been subjected to considerable changes. In this dynamic context, it is interesting to study the evolution of the relationship between performance and governance. Does governance still affect performance? The purpose of this paper is to verify the presence and intensity (extent) of the relationship between corporate governance and performance in Italian listed companies by using both accounting and nonaccounting performance measures. The purpose of this paper is to investigate the effects of prior firm performance on board composition and governance structure of some companies listed on the Italian stock exchange, analysing how a governance approach influences the performance of sample companies. For the research the methodology used is quantitative and we used regression analysis on a sample of 23 Italian listed companies: mechanical companies and public utilities to find that the company's performance was positively related to the size of the board. The empirical analysis conducted allowed us to verify the hypothesis according to which the increase in Corporate Governance Best Practices influences company performance. However, the results we have received do not allow us to arrive at completely unequivocal interpretations. The results showed we have received do not allow us to arrive at completely unequivocal interpretations; the main limit is the sample size used in this study was relatively small

    A Janus Molecule for Screen-Printable Conductive Carbon Ink for Composites with Superior Stretchability

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    Inspired by decades of research in the compatibilization of fillers into elastomeric composites for high-performance materials, a novel polyurethane-based stretchable carbon ink is created by taking advantage of a Janus molecule, 2-(2,5-dimethyl-1H-pyrrol-1-yl)propane-1,3-diol (serinol pyrrole, SP). SP is used to functionalize the carbon and comonomer in the polymer phase. The use of SPs in both the organic and inorganic phases results in an improved interaction between the two phases. When printed, the functionalized material has a factor 1.5 lower resistance-strain dependence when compared to its unfunctionalized analogue. This behavior is superior to commercially available carbon inks. To demonstrate the suitability of ink in an industrial application, an all-printed, elastomer-based force sensor is fabricated. This “pyrrole methodology” is scalable and broadly applicable, laying the foundation for the realization of printed functionalities with improved electromechanical performance.</p

    repair of congenital mitral valve dysplasia in infants and children is it always possible

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    Objectives: Surgical management of congenital malformation of the mitral valve (MV) in the pediatric age group remains a therapeutic challenge for the wide spectrum of the morphological abnormalities and the high incidence of associated cardiac anomalies. We reviewed our experience so as to assess whether MV conservative surgery is always advisable and its results are superior to MV replacement. Methods: Thirty-four consecutive children (20 male and 14 female) with a mean age of 5.9 years (range 45 days‐18 years) treated surgically for congenital MV disease between January 1987 and June 1999. Four patients (11.7%) were under 12 months of age, while 21 patients (62%) were younger than 5 years. Twenty-two patients presented with MV incompetence (or prevalent incompetence), while 12 presented with stenosis (or prevalent stenosis). Associated cardiac lesions were present in 22 patients (62.8%). Results: Mitral valve reconstruction was possible in all. There were no operative deaths. Three patients required reoperation for MV restenosis (a re-repair in one and MV replacement with mechanical prosthesis in two) 4 months, 27 months and 5.6 years after repair with no operative deaths. There was only one late death for prosthetic valve thrombosis. Follow-up data reveal that the 33 surviving patients are asymptomatic and well 4 months‐12 years (mean 72 months) after surgery. At 12 years, actuarial survival and freedom from reoperation are 96.8 and 85.9%, respectively. Echocardiography performed in all of them shows no or mild incompetence or stenosis in 26 (78%), while residual moderate MV incompetence persists in six. Conclusions: Our experience indicates that MV reconstructive procedures in infants and children with congenital MV dysplasia may be effective and reliable with low mortality and low incidence of reoperation rate. Mitral valve repair should always be attempted, especially in infants, despite the frequent severity of MV dysplasia, to avoid the drawbacks of the currently available prostheses. q 2000 Elsevier Science B.V. All rights reserved

    Minimally invasive implantation of continuous flow left ventricular assist devices: the evolution of surgical techniques in a single centre experience

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    To evaluate the evolution of our surgical experience with the implantation of a continuous flow left ventricular assist device (LVAD), from the original full sternotomy approach to less invasive surgical strategies including mini-sternotomy and/or mini-thoracotomies

    Functionalization of graphene related materials with biosourced C-3 and C-6 building blocks. From synthesis to applications

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    The functionalization of sp2 carbon allotropes is one of the hot research topics in advanced research on materials. Nowadays, carbon nanotubes and graphene related materials are extensively studied due to their exceptional mechanical and electrical properties. They are capable of substantially improving the properties of polymeric materials. Their functionalization is a crucial step, for allowing an even dispersion in the matrix. In this research, the functionalization of graphene related materials was performed with biosourced C-3 and C-6 molecules. They were glycerol and galactaric acid derivatives: pyrrole compounds (PyC) and 2-pyrones. The reactions for their synthesis and for the carbon allotrope functionalization were green and characterized by high atom efficiency, with a yield up to 96%. Indeed, the reactions were carried out in the absence of solvents and catalysts and adducts were obtained by simply mixing, with the help of either thermal or mechanical energy. The developed functionalization methods were successful for: carbon black, carbon nanotubes, few layers graphene. The bulk structure of the carbon substrate was left substantially unaltered: functionalization occurred in peripheral positions, at the edges of the graphene layers. Functional groups of defined chemical structure were covalently bound to the carbon material and stable adducts, up to very high temperature, were formed. Reliable hypotheses for the functionalization mechanisms were elaborated. In Figure 1b the supposed domino reaction based on the pyrrole compound, with the Diels Alder cycloaddition as the last step is represented. Such functionalization technique was developed as a pervasive technology, which allowed to pursue a variety of applications: (i) decoration with metals to obtain catalysts for the selective deuteration of pharmaceutical molecules as well as antibacterial ingredients (ii) rubber compounds for dynamic-mechanical applications (tires) (iii) conductive inks

    Bariatric-metabolic surgery versus lifestyle intervention plus best medical care in non-alcoholic steatohepatitis (BRAVES). a multicentre, open-label, randomised trial

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    Background: Observational studies suggest that bariatric-metabolic surgery might greatly improve non-alcoholic steatohepatitis (NASH). However, the efficacy of surgery on NASH has not yet been compared with the effects of lifestyle interventions and medical therapy in a randomised trial. Methods: We did a multicentre, open-label, randomised trial at three major hospitals in Rome, Italy. We included participants aged 25-70 years with obesity (BMI 30-55 kg/m2), with or without type 2 diabetes, with histologically confirmed NASH. We randomly assigned (1:1:1) participants to lifestyle modification plus best medical care, Roux-en-Y gastric bypass, or sleeve gastrectomy. The primary endpoint of the study was histological resolution of NASH without worsening of fibrosis at 1-year follow-up. This study is registered at ClinicalTrials.gov, NCT03524365. Findings: Between April 15, 2019, and June 21, 2021, we biopsy screened 431 participants; of these, 103 (24%) did not have histological NASH and 40 (9%) declined to participate. We randomly assigned 288 (67%) participants with biopsy-proven NASH to lifestyle modification plus best medical care (n=96 [33%]), Roux-en-Y gastric bypass (n=96 [33%]), or sleeve gastrectomy (n=96 [33%]). In the intention-to-treat analysis, the percentage of participants who met the primary endpoint was significantly higher in the Roux-en-Y gastric bypass group (54 [56%]) and sleeve gastrectomy group (55 [57%]) compared with lifestyle modification (15 [16%]; p&lt;0·0001). The calculated probability of NASH resolution was 3·60 times greater (95% CI 2·19-5·92; p&lt;0·0001) in the Roux-en-Y gastric bypass group and 3·67 times greater (2·23-6·02; p&lt;0·0001) in the sleeve gastrectomy group compared with in the lifestyle modification group. In the per protocol analysis (236 [82%] participants who completed the trial), the primary endpoint was met in 54 (70%) of 77 participants in the Roux-en-Y gastric bypass group and 55 (70%) of 79 participants in the sleeve gastrectomy group, compared with 15 (19%) of 80 in the lifestyle modification group (p&lt;0·0001). No deaths or life-threatening complications were reported in this study. Severe adverse events occurred in ten (6%) participants who had bariatric-metabolic surgery, but these participants did not require re-operations and severe adverse events were resolved with medical or endoscopic management. Interpretation: Bariatric-metabolic surgery is more effective than lifestyle interventions and optimised medical therapy in the treatment of NASH. Funding: Fondazione Policlinico Universitario A Gemelli, Policlinico Universitario Umberto I and S Camillo Hospital, Rome, Italy
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