973 research outputs found

    Drug user dynamics: a compartmental model of drug users for scenario analyses

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    A six-typology compartment model of trends in the use of illicit drugs in Italy is developed to evaluate policies and interventions through scenario analyses. Inside the big compartments of just-cannabis users and multiple drug users, three subpopulations are taken into account: the occasional, regular and intensive user. Moreover, compartments for health care, assisted persons together with a constant source (susceptible) are added; removed people (i.e. those who leave drugs for any reason) are put in a compartment which does not participate in the dynamics. Flows from the susceptible reservoir among the drug-user compartments and to the removed or the health care compartments are studied in a deterministic linear ODE framework, where parameters are estimated using Italian data. This system shows an evolution towards a steady state, the speed of convergence being dependent on parameters in a fairly visible way. This model represents a theoretical development in drug policy analysis, as it shows the relevance of flux parameters, which are in principle subject to modifications due to institutional efforts, together with a quantitative evaluation of their role in the evolution of the whole system

    Measuring gait speed to better identify prodromal dementia

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    Abstract Slow gait speed has been shown to predict incident dementia and cognitive decline in older individuals. We aimed to summarize the evidence concerning the association of slow gait speed with cognitive decline and dementia, and discuss the possible shared pathways leading to cognitive and motor impairments, under the unifying hypothesis that body and mind are intimately connected. This is a scoping review supported by a systematic search of the literature, performed on PubMed and Web of Science. Longitudinal studies providing information on the role of gait speed in the prediction of cognitive decline and dementia in cognitively intact people and in those with initial cognitive impairment were eligible. Of 39 studies selected, including overall 57,456 participants, 33 reported a significant association between gait speed and cognitive outcomes, including dementia. Neurodegenerative pathology and cerebrovascular burden may damage cerebral areas involved in both cognitive functions and motor control. At the same time, systemic conditions, characterized by higher cardiorespiratory, and metabolic and inflammatory burden, can affect a number of organs and systems involved in motor functions, including the brain, having ultimately an impact on cognition. The interplay of body and mind seems relevant during the development of cognitive decline and dementia. The measurement of gait speed may improve the detection of prodromal dementia and cognitive impairment in individuals with and without initial cognitive deficits. The potential applicability of such a measure in both clinical and research settings points at the importance of expanding our knowledge about the common underlying mechanisms of cognitive and motor decline

    Evaluation of electrospun spinel-type high-entropy (Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)3O4, (Cr0.2Mn0.2Fe0.2Co0.2Zn0.2)3O4 and (Cr0.2Mn0.2Fe0.2Ni0.2Zn0.2)3O4 oxide nanofibers as electrocatalysts for oxygen evolution in alkaline medium

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    Electrochemical water splitting is a promising sustainable-energy technology, but the slow kinetics of the oxygen evolution reaction represents a limitation for its broad market penetration. Spinel-structured transition metal (TM) oxides have shown great potential as a sustainable alternative to precious metal-based electrocatalysts. High-entropy oxides (HEOs) with multiple TM-cation sites lend themselves to engineering of the octahedral redox-active centres to enhance the catalyst reactivity. This work focuses on the preparation of electrospun spinel-type HEO nanofibers (NFs), based on equimolar (Cr,Mn,Fe,Co,Ni), (Cr,Mn,Fe,Co,Zn) and (Cr,Mn,Fe,Ni,Zn) combinations, and their evaluation as electrocatalysts in alkaline medium together with (Cr,Mn,Fe,Co,Ni) HEO nanoparticles (NPs) prepared via the sol-gel method. (Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)3O4 NFs and NPs (Tafel slopes: 49.1 and 51.3 mV dec−1, respectively) outperform both (Cr0.2Mn0.2Fe0.2Co0.2Zn0.2)3O4 and (Cr0.2Mn0.2Fe0.2Ni0.2Zn0.2)3O4 NFs (62.5 and 59.6 mV dec−1, respectively) and IrO2 reference electrocatalyst (52.9 mV dec−1). The higher concentration of oxygen vacancies on their surface and the higher occupation of octahedral sites by redox-active Co2+ and Ni2+ centres are responsible for their behaviour. The present electrospun HEO NFs have great potential as ink-jet printable electrocatalysts

    New Insight on Medieval Painting in Sicily: The Virgin Hodegetria Panel in Monreale Cathedral (Palermo, Italy)

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    : The Virgin Hodegetria, located in the Cathedral of Santa Maria Nuova in Monreale, near Palermo (Italy), probably dating the first half of the 13th century, is one of the earliest examples of medieval panel painting in Sicily. A diagnostic campaign was carried out on the panel aiming to identify the constituting materials and the executive technique, as well as to assess the state of conservation for supporting the methodological choice of the restoration intervention. Both non invasive (X-ray radiography, digital microscope, multispectral imaging, ED-X-ray fluorescence) and micro-invasive (polarised light microscopy, ESEM-EDX, ATR-FTIR spectroscopy and micro-Raman spectroscopy) analyses were performed. According to the results, the executive technique followed the 13th–14th-century Italian painting tradition. A complex structure was applied on the wooden support, consisting of a double layer of canvas and several ground layers of gypsum and glue based binder. The underdrawing was made by a brush using carbonaceous black pigment. The original palette includes red ochre, red lead, azurite, carbon black and bone black. During the several restorations, mercury-based red, indigo, smalt blue, orpiment and synthetic mars were used. The original silver leaf of the frame was covered with red tin-based lake and subsequently regilded with gold leaf. Proteinaceous and oil binders were also detecte

    Pathological implications of Th1/Th2 cytokine genetic variants in Beh\ue7et's disease: Data from a pilot study in a Sicilian population

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    Cytokines act as pleiotropic polypeptides able to regulate inflammatory/immune responses and to provide important signals in physiological and pathological processes. Several cytokines (Th1, Th2, and Th17) seem to be involved in the pathophysiology of Beh\ue7et's disease, a chronic immune-mediated disease characterized by oral and genital lesions and ocular inflammation. Its individual susceptibility seems to be modulated by genetic variants in genes codifying these cytokines. Th1 and Th17 seem to be involved in the disease's active phases, and Th2 seems to affect the development or severity of the disease; however, contrasting data are reported. In this study, some genetic variants of the Th1/Th2 cytokine genes were investigated in Sicilian patients and age- and gender-matched controls. Three very significant associations with Beh\ue7et's disease were detected, and combined genotypes associated with increased disease risk were identified. Results obtained point to the key role of Th1/Th2 cytokine genetic variants in disease susceptibility

    social engagement in late life may attenuate the burden of depressive symptoms due to financial strain in childhood

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    Abstract Background : It remains poorly understood if childhood financial strain is associated with old-age depression and if active social life may mitigate this relationship. Aims : To investigate the association between childhood financial strain and depressive symptoms during aging; to examine whether late-life social engagement modifies this association. Method : 2884 dementia-free individuals (aged 60+) from the Swedish National study of Aging and Care-Kungsholmen were clinically examined over a 15-year follow-up. Presence of childhood financial strain was ascertained at baseline. Depressive symptoms were repeatedly assessed with the Montgomery–Asberg Depression Rating Scale. Social engagement comprised information on baseline social network and leisure activities. Linear, logistic and mixed-effect models estimated baseline and longitudinal associations accounting for sociodemographic, clinical, and lifestyle factors. Results : Childhood financial strain was independently associated with a higher baseline level of depressive symptoms (β = 0.37, 95%CI 0.10-0.65), but not with symptom change over time. Relative to those without financial strain and with active social engagement, depressive burden was increased in those without financial strain but with inactive social engagement (β = 0.43, 95%CI: 0.15-0.71), and in those with both financial strain and inactive engagement (β = 0.99; 95%CI: 0.59-1.40). Individuals with financial strain and active social engagement exhibited similar depressive burden as those without financial strain and with active social engagement. Limitations : Recall bias and reverse causality may affect study results, although sensitivity analyses suggest their limited effect. Conclusions : Early-life financial strain may be of lasting importance for old-age depressive symptoms. Active social engagement in late-life may mitigate this association

    Behçet’s disease and celiac disease: a rare association or a possible link?

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    Modified Newton-Raphson Method to Tune Feedback Gains of Control System for Standing by Functional Neuromuscular Stimulation Following Spinal Cord Injury

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    Background: Functional neuromuscular stimulation (FNS) can restore standing capabilities following spinal cord injury. Feedback control of these systems can optimize performance by reducing the required upper extremity support. However, tuning these control systems can be intensive and clinically inconvenient
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