369 research outputs found
Unimpaired Neuropsychological Performance and Enhanced Memory Recall in Patients with Sbma: A Large Sample Comparative Study.
Peculiar cognitive profile of patients with SBMA has been described by fragmented literature. Our retrospective study reports the neuropsychological evaluations of a large cohort of patients in order to contribute towards the understanding of this field. We consider 64 neuropsychological evaluations assessing mnesic, linguistic and executive functions collected from 2013 to 2015 in patients attending at Motor Neuron Disease Centre of University of Padova. The battery consisted in: Digit Span forwards and backwards, Prose Memory test, Phonemic Verbal fluency and Trail making tests. ANCOVA statistics were employed to compare tests scores results with those obtained from a sample of healthy control subjects. Multiple linear regressions were used to study the effect on cognitive performance of CAG-repeat expansion, the degree of androgen insensitivity and their interaction to cognitive performance. Statistical analyses did not reveal altered scores in any neuropsychological tests among those adopted. Interestingly, patients performed significantly better in the Prose Memory test's score. No relevant associations were found with genetic, hormonal or clinical patients' profile. Results inconsistent with previous studies have been interpreted according to the phenomenon of somatic mosaicism. We suggest a testosterone-related and the mood state-dependant perspectives as two possible interpretations of the enhanced performances in the Prose Memory test. Further studies employing more datailed tests batteries are encouraged
Design of a Stationary Energy Recovery System in Rail Transport
Although rail is one of the most sustainable transport systems, there is still room to reduce its energy demand. In particular, during the braking of DC powered trains, a significant amount of energy is wasted. The recent developments in energy storage system technologies, combined with the widely used technique of regenerative braking, can considerably increase energy saving. This paper explores this theme, quantifying the amount of braking energy that can be potentially recovered in a real case study, starting from the experimental data measured on-board train. A simplified numerical model of the recovery process has been implemented. Adopting it, the energy that can be saved, with one or two energy storage systems, has been quantified for each possible position along the track. The procedure allows to determine the optimal position. Further findings about the impact of voltage level on the efficiency of the recovery process have been reported. The optimal level of voltage has been determined, also considering the additional losses in the catenary, both during the traction and braking phase of the train. Moreover, it allows dimensioning of stationary storage systems considering two different energy management strategies and their impact on the peak of stored energy. The proposed approach will be presented with reference to the concrete case of a specific route on the Italian rail network, analyzing a train in normal commuter service and the obtained results will be discussed. In the best situation, about the 73% of the braking energy can be recovered
Measuring the impact of reversible substations on energy efficiency in rail transport
open6Nowadays great interest is placed on the environmental issue. Greenhouse gas emissions are more than 50% higher than in 1990. European energy policy has been supporting efficient energy management in order to reduce the railway transport emissions by 50% within 2030. The railway stakeholders are encouraged to adopt technological solutions to foster energy efficiency. The electrodynamic braking combined with the adoption of reversible substations is one of the most promising solutions. In order to evaluate the impact of this innovative technology, a measurement campaign has been conducted on Metro de Madrid where a reversible substation was installed. In this paper, a preliminary analysis on the data acquired is presented. Traceable and accurate on-board train measurements of the energy flows and the losses are fundamental to quantify the impact of these new technologies and to carry out a survey on the efficiencies of the different vehicle components and on the strategies to reduce the energy consumption in the various operation modes. © IMEKO TC-4 2020.openCascetta F., Cipolletta G., Delle Femine A., Gallo D., Giordano D., Signorino D.Cascetta, F.; Cipolletta, G.; Delle Femine, A.; Gallo, D.; Giordano, D.; Signorino, D
Effects of Orthogonal Rotating Electric Fields on Electrospinning Process
Electrospinning is a nanotechnology process whereby an external electric
field is used to accelerate and stretch a charged polymer jet, so as to produce
fibers with nanoscale diameters. In quest of a further reduction in the cross
section of electrified jets hence of a better control on the morphology of the
resulting electrospun fibers, we explore the effects of an external rotating
electric field orthogonal to the jet direction. Through extensive particle
simulations, it is shown that by a proper tuning of the electric field
amplitude and frequency, a reduction of up to a in the aforementioned
radius can be obtained, thereby opening new perspectives in the design of
future ultra-thin electrospun fibres. Applications can be envisaged in the
fields of nanophotonic components as well as for designing new and improved
filtration materials.Comment: 22 pages, 8 figure
Enhanced GRK2 expression and desensitization of betaAR vasodilatation in hypertensive patients.
Increased levels of G protein coupled receptor kinase GRK2 appear to participate in hypertension presumably through the desensitization of beta adrenergic receptors (betaARs) that mediate vasodilatation. There are contrasting data on the occurrence of betaAR desensitization in the vasculature, we therefore investigated betaAR vasodilatation and desensitization in normotensives and in hypertensive humans. In blood lymphocytes, we assessed betaAR signaling and GRK2 expression and found betaAR signaling alterations and, consistent with desensitization, ncreased GRK2 levels in hypertensives. We studied in vivo vasodilatation to the betaAR agonist isoproterenol (ISO) injected in the brachia artery in control conditions and during the concomitant infusion of heparin, a known in vitro nonspecific GRK inhibitor. ISO induced a dose-dependent vasorelaxation that was attenuated in hypertensives indicating a loss of betaAR signaling. Intra-arterial infusion of heparin nhibited lymphocyte GRK2 activity and prevented desensitization of betaAR vasodilatation in normotensives. In hypertensives, heparin restored vasodilatation to ISO, to levels observed in normotensives. Our results suggest that betaAR desensitization does indeed occur at the vascular levels in vivo, and that heparin by acting as a GRK inhibitor prevents this in normotensives and restores impaired betaAR vasodilation in hypertensives. We conclude that desensitization participates to impaired betaAR vasodilation in hypertension
Interventional Ultrasound in Dermatology: A Pictorial Overview Focusing on Cutaneous Melanoma Patients
Cutaneous melanoma incidence is increasing worldwide, representing an aggressive tumor when evolving to the metastatic phase. High-resolution ultrasound (US) is playing a growing role in the assessment of newly diagnosed melanoma cases, in the locoregional staging prior to the sentinel lymph-node biopsy procedure, and in the melanoma patient follow-up. Additionally, US may guide a number of percutaneous procedures in the melanoma patients, encompassing diagnostic and therapeutic modalities. These include fine needle cytology, core biopsy, placement of presurgical guidewires, aspiration of lymphoceles and seromas, and electrochemotherapy
A focus group study for the design of a web-based tool for improving problem-solving in older adults
The development of easily accessible and usable social and cognitive enhancement trainings is becoming a priority to reduce the impact of aging on quality of life. Since most activities of daily living (e.g., making a meal) require problem-solving skills, problem-solving interventions could be used to improve and/or maintain functional abilities in aging to prolong independence. To design an effective problem-solving training and increase older adults' adherence to the training, this study examined older adults' perceptions of their challenges in activities of daily living, their skills and difficulties in using information technology (IT), and their motivations and expectations for participating in a web-based problem-solving training activity. Four focus groups (two in Italy and two in the Netherlands) were conducted with older adults aged between 65 and 84 years, a total of 27 participants. The data were analyzed using the Atlas.ti 8 software for the thematic analysis. The analysis identified five thematic areas: interests and activities, difficulties and concerns, experiences and motivations for training, expertise and resources, suggestions for the design of the new training. The results were used to develop a first prototype of a Shared, Web-based, Intelligent Flexible Thinking Training (SWIFT), adapted to future user needs. The participation of older adults in this design phase was critical to understanding their needs, motivations, and expectations regarding the implementation and use of a cognitive enhancement training.</p
Ameliorating the Courant-Friedrichs-Lewy condition in spherical coordinates: A double FFT filter method for general relativistic MHD in dynamical spacetimes
Numerical simulations of merging compact objects and their remnants form the
theoretical foundation for gravitational wave and multi-messenger astronomy.
While Cartesian-coordinate-based adaptive mesh refinement is commonly used for
simulations, spherical-like coordinates are more suitable for nearly spherical
remnants and azimuthal flows due to lower numerical dissipation in the
evolution of fluid angular momentum, as well as requiring fewer numbers of
computational cells. However, the use of spherical coordinates to numerically
solve hyperbolic partial differential equations can result in severe
Courant-Friedrichs-Lewy (CFL) stability condition timestep limitations, which
can make simulations prohibitively expensive. This paper addresses this issue
for the numerical solution of coupled spacetime and general relativistic
magnetohydrodynamics evolutions by introducing a double FFT filter and
implementing it within the fully MPI-parallelized SphericalNR framework in the
Einstein Toolkit. We demonstrate the effectiveness and robustness of the
filtering algorithm by applying it to a number of challenging code tests, and
show that it passes these tests effectively, demonstrating convergence while
also increasing the
timestep significantly compared to unfiltered simulations.Comment: 15 pages, 13 figures, revtex4-
Collapse of spherical charged anisotropic fluid spacetimes
A class of spherical collapsing exact solutions with electromagnetic charge
is derived. This class of solutions -- in general anisotropic -- contains
however as a particular case the charged dust model already known in
literature. Under some regularity assumptions that in the uncharged case give
rise to naked singularities, it is shown that the process of shell focusing
singularities avoidance -- already known for the dust collapse -- also takes
place here, determing shell crossing effects or a completely regular solution.Comment: 13 pages, 2 figures. Version to appear on Class Quantum Gra
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