556 research outputs found

    Effect of lower-limb joint models on subject-specific musculoskeletal models and simulations of daily motor activities

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    Understanding the validity of using musculoskeletal models is critical, making important to assess how model parameters affect predictions. In particular, assumptions on joint models can affect predictions from simulations of movement, and the identification of image-based joints is unavoidably affected by uncertainty that can decrease the benefits of increasing model complexity. We evaluated the effect of different lower-limb joint models on muscle and joint contact forces during four motor tasks, and assessed the sensitivity to the uncertainties in the identification of anatomical four-bar-linkage joints. Three MRI-based musculoskeletal models having different knee and ankle joint models were created and used for the purpose. Model predictions were compared against a baseline model including simpler and widely-adopted joints. In addition, a probabilistic analysis was performed by perturbing four-bar-linkage joint parameters according to their uncertainty. The differences between models depended on the motor task analyzed, and there could be marked differences at peak loading (up to 2.40 BW at the knee and 1.54 BW at the ankle), although they were rather small over the motor task cycles (up to 0.59 BW at the knee and 0.31 BW at the ankle). The model including more degrees of freedom showed more discrepancies in predicted muscle activations compared to measured muscle activity. Further, including image-based four-bar-linkages was robust to simulate walking, chair rise and stair ascent, but not stair descent (peak standard deviation of 2.66 BW), suggesting that joint model complexity should be set according to the imaging dataset available and the intended application, performing sensitivity analyses

    Wine Routes and Sustainable Social Organization within Local Tourist Supply: Case Studies of Two Italian Regions

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    The paper is aimed at investigating wine companies’ perceptions and attitudes towards the role of wine routes as an actual tool to improve their tourist attractiveness and sustainable tourism on a territorial level. Through a comparative approach, some wineries from the Italian regions of Abruzzo and Tuscany have been surveyed and in-depth-interviews to key local stakeholders have been conducted. The aim of the survey is to investigate the companies’ perception about wine tourists’ characteristics and wine route management. Through a multivariate analysis, the reasons behind wineries’ satisfaction/discontent have been analyzed. The findings identify a close relation between the complexity of the services offered, the companies’ involvement in the wine routes management and their satisfaction about the results obtained. The more complex the services are, the more satisfied the companies. The comparative analysis of the strengths and weaknesses pointed out by the wineries’ keepers has allowed some general considerations about the tools to use for the improvement of wine routes management. In a broader sense, the wineries’ direct involvement both in investment and in governance appears to be key in the success of the routes as a model for local tourism development

    Different patterns of cortical excitability in major depression and vascular depression: a transcranial magnetic stimulation study

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    BACKGROUND: Clinical and functional studies consider major depression (MD) and vascular depression (VD) as different neurobiological processes. Hypoexcitability of the left frontal cortex to transcranial magnetic stimulation (TMS) is frequently reported in MD, whereas little is known about the effects of TMS in VD. Thus, we aimed to assess and compare motor cortex excitability in patients with VD and MD. METHODS: Eleven VD patients, 11 recurrent drug-resistant MD patients, and 11 healthy controls underwent clinical, neuropsychological and neuroimaging evaluations in addition to bilateral resting motor threshold, cortical silent period, and paired-pulse TMS curves of intracortical excitability. All patients continued on psychotropic drugs, which were unchanged throughout the study. RESULTS: Scores on one of the tests evaluating frontal lobe abilities (Stroop Color-Word interference test) were worse in patients compared with controls. The resting motor threshold in patients with MD was significantly higher in the left hemisphere compared with the right (p < 0.05), and compared with the VD patients and controls. The cortical silent period was bilaterally prolonged in MD patients compared with VD patients and controls, with a statistically significant difference in the left hemisphere (p < 0.01). No differences were observed in the paired-pulse curves between patients and controls. CONCLUSIONS: This study showed distinctive patterns of motor cortex excitability between late-onset depression with subcortical vascular disease and early-onset recurrent drug resistant MD. The data provide a TMS model of the different processes underlying VD and MD. Additionally, our results support the “Vascular depression hypothesis” at the neurophysiological level, and confirm the inter-hemispheric asymmetry to TMS in patients with MD. We were unable to support previous findings of impaired intracortical inhibitory mechanisms to TMS in patients with MD, although a drug-induced effect on our results cannot be excluded. This study may aid the understanding of the pathogenetic differences underlying the clinical spectrum of depressive disorders

    Stochastic Order in Macromolecular Solutions: a SANS Experiment

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    A SANS experiment has been performed in solutions of /S-lactoglobulin at different concentrations. According to previous results, a definite structure factor can be extracted, besides a careful evaluation of the form factor. The results are discussed within the frame of a phenomenological stochastic model that allows parametrization of the experimental results in terms of preferred lengths. The occurrence of preferred lengths, almost independent from the concentration, suggests the existence of well defined local structures in which both spatial and rotational orders are involved. A suggestion from the numerical values of the implied parameters points to a distance of 120 Å that would characterize the interaction potential

    Non-pegylated liposomal doxorubicin plus ifosfamide in metastatic soft tissue sarcoma: results from a phase-II trial

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    Non-pegylated liposomal doxorubicin (NPLD) has demonstrated antitumour activity equivalent to conventional doxorubicin and a significantly lower risk of cardiotoxicity. This phase II trial was performed to evaluate the activity and the safety of NPLD and ifosfamide combination in patients with metastatic soft tissue sarcoma

    Development and characterization of a gold nanoparticles glassy carbon modified electrode for dithiotreitol (DTT) detection suitable to be applied for determination of atmospheric particulate oxidative potential

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    A gold nanostructured electrochemical sensor based on modified GC electrode for thiols' detection is described and characterized. This sensor is a suitable device for the measurement of the oxidative potential (OP) of the atmospheric particulate matter (PM), considered a global indicator of adverse health effects of PM, as an alternative to the classic spectrophotometric methods. The operating principle is the determination of the OP, through the measurement of the consumption of DTT content. The DTT-based chemical reactivity is indeed a quantitative acellular probe for assessment of the capacity of the atmospheric PM to catalyze reactive oxygen species generation which contributes to the induction of oxidative stress in living organisms and in turn to the outcome of adverse health effects. To make the sensors, glassy carbon electrodes, traditional (GC) and screen printed (SPE) electrodes, have been electrochemically modified with well-shaped rounded gold nanoparticles (AuNPs) by using a deposition method that allows obtaining a stable and efficient modified surface in a very simple and reproducible modality. The chemical and morphological characterization of the nano-hybrid material has been performed by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy coupled with electron dispersive spectroscopy analysis (SEM/EDS). The electrochemical properties have been evaluated by cyclic voltammetry (CV) and chrono-amperometry (CA) in phosphate buffer at neutral pH as requested in DTT assay for OP measurements. The electroanalytical performances of the sensor in DTT detection are strongly encouraging showing low LODs (0.750 ÎŒM and 1.5 ÎŒM), high sensitivity (0.0622 ÎŒA cm−2 ÎŒM−1 and 0.0281 ÎŒA cm−2 ÎŒM−1), wide linear and dynamic ranges extending over 2-4 orders of magnitude and high selectivity. FIA preliminary results obtained on measuring the DTT rate consumption in six PM aqueous extracts samples showed a good correlation with measurements obtained in parallel on the same set of samples by using the classic spectrophotometric method based on the Ellman's reactive use. These results confirm the high selectivity of the method and its suitability for application to be applied in PM oxidative potential measurements
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