439 research outputs found

    Organic Solar Cells: Problems and Perspectives

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    For photovoltaic cells to convert solar into electric energy is probably the most interesting research challenge nowadays. A good efficiency of these devices has been obtained by using inorganic semiconductor materials. On the other hand, manufacture processes are very expensive in terms of both materials and techniques. For this reason organic-based photovoltaic (OPV) cells are attracting the general attention because of the possible realization of more economical devices. Organic materials are abundant and easily handling. Unfortunately OPV cells efficiency is significantly lower than that of inorganic-based devices, representing a big point of weakness at the present. This is mainly due to the fact that organic semiconductors have a much higher band gap with respect to inorganic semiconductors. In addition, OPV cells are very susceptible to oxygen and water. In this paper we will describe some of the different approaches to the understanding and improving of organic photovoltaic devices

    Targeting oxidative stress for improving cardiovascular performance in the elderly

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    Oxidative stress is implicated in the pathophysiology of several cardiovascular diseases, as evidenced by correlation between oxidative stress markers and Heart Failure (HF) and by direct molecular evidence for an etiological role of reactive oxygen species (ROS). ROS play an important role in signalling processes, but their overproduction generates oxidative stress. Previous studies demonstrated that HF was associated with antioxidant deficit as well as increased oxidative stress. Furthermore, these changes correlated with the hemodynamic function, suggesting their role in the pathogenesis of cardiac dysfunction. An important mechanism involved in cellular cardiovascular response is represented by sirtuins. SIRT1 inhibition determines suppression of genes ac tivated by exposure to heat shock, on the contrary, SIRT1 activation enhances the heat shock response. Then the ability of SIRT1 to modulate stress resistance is multifaceted and not only linked to oxidative stress, but also to other stressful stimuli. Recently several studies have demonstrated the capability of physical activity to induce SIRT1 activity and, in turn, the ability of this enzyme to mediate the favourable antioxidant effects of the exercise training. Other agents able to induce SIRT1 activity have demonstrated some effects on cardiac function. Resveratrol supplementation has been shown to decrease cardiovascular risk factors, and the positive effect of resveratrol on training response and aerobic capacity in rats to be mediated via SIRT1. The future research should be addressed to better clarify the possible role of the antioxidants therapy in clinical studies, in particular defining a standardization of procedures, doses and duration of treatment

    Exercise training in aging and diseases.

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    Sedentary lifestyle along with high blood pressure, abnormal values for blood lipids, smoking, and obesity are recognized risk factors for cardiovascular diseases and for many other chronic diseases, such as diabetes, osteoporosis, breast and colon cancer. Several studies conducted on large cohort of individuals have documented the protective effects of physical activity for both vascular and nonvascular syndromes. Exercise training is an integral part of cardiac rehabilitation, a complex therapeutic approach, effective both in young and elderly patients. Despite the number of evidences underling the benefits associated with physical fitness, the cardiac rehabilitation is still an underused medical resource. The molecular mechanism behind physical activity protective effect is presently unresolved, and further studies are also needed to establish the best protocol in terms of specificity, volume and duration of the training

    Antioxidant Supplementation in the Treatment of Aging-Associated Diseases

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    Oxidative stress is generally considered as the consequence of an imbalance between pro- and antioxidants species, which often results into indiscriminate and global damage at the organismal level. Elderly people are more susceptible to oxidative stress and this depends, almost in part, from a decreased performance of their endogenous antioxidant system. As many studies reported an inverse correlation between systemic levels of antioxidants and several diseases, primarily cardiovascular diseases, but also diabetes and neurological disorders, antioxidant supplementation has been foreseen as an effective preventive and therapeutic intervention for aging-associated pathologies. However, the expectations of this therapeutic approach have often been partially disappointed by clinical trials. The interplay of both endogenous and exogenous antioxidants with the systemic redox system is very complex and represents an issue that is still under debate. In this review a selection of recent clinical studies concerning antioxidants supplementation and the evaluation of their influence in aging-related diseases is analyzed. The controversial outcomes of antioxidants supplementation therapies, which might partially depend from an underestimation of the patient specific metabolic demand and genetic background, are presented

    Hydropinotherapy with sulphurous mineral water as complementary treatment to improve glucose metabolism, oxidative status, and quality of life

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    Hydropinotherapy is a salus per aquam (Spa) treatment suitable as a complementary approach to treat several diseases, which strongly affect the quality of life (QoL). Hydropinotherapy with sulphurous mineral water exerts benefits thanks to components, such as hydrogen sulphide, which is considered mainly responsible for antioxidant and hypoglycaemic effects. Such properties, linked from each other, could favour an improvement in patients’ QoL. However, data on humans are scarce. This study aimed to investigate whether a cycle of sulphurous hydropinotherapy was able to modify plasma levels of glucose and reactive oxygen metabolites (ROMs) and improve QoL in patients suffering from several chronic disorders. A prospective, observational study involved patients with gastrointestinal diseases who received a prescription of a cycle of sulphurous hy-dropinotherapy (S-HT). Age-and sex-matched control group was enrolled (No S-HT). Glycaemia and plasma concentration of ROMs were measured in all subjects. The impact of spa treatment on the QoL was assessed using the Short Form 36 Health Status Survey questionnaire (SF-36). All parameters were measured at baseline and at the end of a 2-week treatment. Between the groups, no differences were found in glycaemia and ROMs at baseline. In the S-HT group, a reduction in glycaemia and ROMs, both in respect to baseline (p = 0.005 and p = 0.031, respectively) and to control group, as shown by the delta value calculated, as the difference between the values at 2 weeks and baseline (p = 0.0009 and p = 0.0001, respectively). In the S-HT, delta ROMs was the best predictor of delta glycaemia with a direct linear correlation (beta = 0.559, 95% CI 0.471 to 0.647, p < 0.0001). In the S-HT, the SF-36 total score was improved both when compared with baseline (p = 0.002) and with No S-HT (p = 0.001). Sulphurous hydropinotherapy induces a decrease in glycaemia and ROM levels, also ameliorating the patients’ QoL. Therefore, it could be considered a useful complementary therapeutic approach

    The influence of open innovation on firm performance

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    Innovation is crucial for growth and business development, and represents a reliable way through which to gain competitiveness within the marketplace. Open innovation is expressed through three different processes: the acquisition of external technology (inbound innovation); the external exploitation of technology (outbound innovation); and coupled innovation. Based on a comprehensive and systematic review of the literature best able to detect the main thematic areas of the research topic, the aim of this paper is to investigate how the paradigm of open innovation influences firm performance and to provide suggestions for future research avenues

    Ocular Refraction at Birth and Its Development During the First Year of Life in a Large Cohort of Babies in a Single Center in Northern Italy

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    The purpose of this study was to investigate refraction at birth and during the first year of life in a large cohort of babies born in a single center in Northern Italy. We also aimed to analyze refractive errors in relation to the gestational age at birth. An observational ophthalmological assessment was performed within 24 h of birth on 12,427 newborns. Refraction was examined using streak retinoscopy after the administration of tropicamide (1%). Values in the range of between +0.50 ≤ D ≤ +4.00 were defined as physiological refraction at birth. Newborns with refraction values outside of the physiological range were followed up during the first year of life. Comparative analyses were conducted in a subgroup of babies with known gestational ages. The following distribution of refraction at birth was recorded: 88.03% of the babies had physiological refraction, 5.03% had moderate hyperopia, 2.14% had severe hyperopia, 3.4%, had emmetropia, 0.45%, had myopia, 0.94% had astigmatism, and 0.01% had anisometropia. By the end of the first year of life, we observed reductions in hyperopia and astigmatism, and stabilization of myopia. Preterm babies had a four-fold higher risk of congenital myopia and a three-fold higher risk of congenital emmetropia as compared to term babies. Refraction profiles obtained at birth changed during the first year of life, leading to a normalization of the refraction values. Gestational age at birth affected the incidence of refractive errors and amblyopia
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