Psychological Well-Being in Obese Inpatients with Ischemic Heart Disease at Entry and at Discharge from a Four-Week Cardiac Rehabilitation Program

The purposes of this observational pre-post study were twofold: 1- to evaluate psychological health in obese patients with ischemic heart disease at admission to cardiac rehabilitation (CR) and 2 – to examine the effectiveness of a 4-week CR residential program in improving obese patients’ psychological well-being at discharge from CR. A sample of 177 obese patients completed the Psychological General Well-Being Inventory (PGWBI) at admission to the CR program and at discharge. The equivalence testing method with normative comparisons was used to determine the clinical significance of improvements after having established that baseline mean scores on the PGWBI scales were significantly lower than normal means. Results show that patients scored equally or better than norms on many PGWBI dimensions at admission to CR but scored significantly worse on Global Score, Vitality and Self-control. At discharge, mean scores that were impaired at baseline returned to normal levels at the more conservative equivalence interval. A 4-week CR program was thus effective in improving obese patients’ psychological well-being. The equivalence testing method allowed to establish the clinical significance of such improvement

Enhancing Light Harvesting by Hierarchical Functionally Graded Transparent Conducting Al-doped ZnO Nano- and Mesoarchitectures

A functionally graded Al-doped ZnO structure is presented which combines conductivity, visible transparency and light scattering with mechanical flexibility. The nano and meso-architecture, constituted by a hierarchical, large surface area, mesoporous tree-like structure evolving in a compact layer, is synthesized at room temperature and is fully compatible with plastic substrates. Light trapping capability is demonstrated by showing up to 100% improvement of light absorption of a low bandgap polymer employed as the active layer.Comment: 21 pages, 6 figures, submitted to Solar Energy Materials and Solar Cell

Morphology-driven electrical and optical properties in graded hierarchical transparent conducting Al:ZnO

Graded Al-doped ZnO layers, constituted by a mesoporous forest like system evolving into a compact transparent conductor, were synthesized by Pulsed Laser Deposition with different morphology to study the correlation with functional properties. Morphology was monitored by measuring the resulting surface roughness and its effects on electrical conductivity (especially carrier mobility, which significantly decreases with increasing roughness) allow to discuss the limitations in conduction mechanisms. Significant changes in light scattering capability due to variations in morphology are also investigated and discussed to study the correlation between morphology and functional properties.Comment: 11 pages, 4 figure

Skeletal muscle characteristics and motor performance after 2-year growth hormone treatment in adults with prader-willi syndrome.

Context:In adults with Prader-Willi syndrome (PWS), abnormal body composition with decreased lean body mass and skeletal muscle (SM) volume has been related to altered GH secretion and may possibly contribute to greatly reduced motor capacity.Objective:The scope of the study was to test the hypothesis that GH treatment has favorable effects on SM characteristics and motor performance in adults with PWS.Design, Setting, and Participants:Fifteen obese PWS subjects (nine males and six females; age range, 19–35 y; body mass index, 37.7–59.9 kg/m2) were investigated before and after 12 (GH12) and 24 (GH24) months of GH treatment.Main Outcome Measures:SM cross-sectional area and SM attenuation were determined with computed tomography at the lumbar and midthigh levels. Maximal isometric handgrip strength and isokinetic knee extension peak torque were measured. Motor performance was evaluated with different indoor walking tests, whereas exercise endurance was assessed with a treadmill incremental test to exhaustion.Results:A condition of severe GH deficiency was found in six patients (40%). GH treatment significantly increased lean body mass (GH12, P < .05; GH24, P < .05), reduced percentage of body fat (GH12, P < .05; GH24, P < .05), and augmented SM cross-sectional area and SM attenuation of both lumbar (GH12, P < .01; GH24, P < .001) and thigh muscles (GH24, P < .05). Handgrip strength increased by 7% at GH12 (P < .05) and by 13% at GH24 (P < .001). Peak torque of knee extension extrapolated at zero angular velocity was significantly higher at GH24 (P < .01), and exercise endurance rose by 13% (P < .05) and 17% (P < .05) before exhaustion at GH12 and GH24, respectively, whereas no change was detected with walking tests. No significant difference in the response to GH treatment was detected between patients with and without GH deficiency.Conclusion:Long-term GH treatment in adult PWS patients improves body composition and muscle size and quality and increases muscle strength and exercise tolerance independently from the GH secretory status

Structure-dependent optical and electrical transport properties of nanostructured Al-doped ZnO

The structure-property relation of nanostructured Al-doped ZnO thin films has been investigated in detail through a systematic variation of structure and morphology, with particular emphasis on how they affect optical and electrical properties. A variety of structures, ranging from compact polycristalline films to mesoporous, hierarchically organized cluster assemblies, are grown by Pulsed Laser Deposition at room temperature at different oxygen pressures. We investigate the dependence of functional properties on structure and morphology and show how the correlation between electrical and optical properties can be studied to evaluate energy gap, conduction band effective mass and transport mechanisms. Understanding these properties opens the way for specific applications in photovoltaic devices, where optimized combinations of conductivity, transparency and light scattering are required.Comment: 8 pages, 9 figure

Multi-wavelength Raman scattering of nanostructured Al-doped zinc oxide

In this work we present a detailed Raman scattering investigation of zinc oxide and aluminum-doped zinc oxide (AZO) films characterized by a variety of nanoscale structure and morphology and synthesized by pulsed laser deposition (PLD) under different oxygen pressure conditions. The comparison of Raman data for pure ZnO and AZO films with similar morphology at the nano/mesoscale allows to investigate the relation between Raman features (peak or band positions, width, relative intensity) and material properties such as local structural order, stoichiometry and doping. Moreover Raman measurements with three different excitation lines (532, 457 and 325 nm) point out a strong correlation between vibrational and electronic properties. This observation confirms the relevance of a multi-wavelength Raman investigation to obtain a complete structural characterization of advanced doped oxide materials.Comment: 27 pages, 7 figures, submitted to the Journal of Applied Physic

Tuning electrical properties of hierarchically assembled Al-doped ZnO nanoforests by room temperature Pulsed Laser Deposition

Large surface area, 3D structured transparent electrodes with effective light management capability may represent a key component in the development of new generation optoelectronic and energy harvesting devices. We present an approach to obtain forest-like nanoporous/hierarchical Al-doped ZnO conducting layers with tunable transparency and light scattering properties, by means of room temperature Pulsed Laser Deposition in a mixed Ar:O2 atmosphere. The composition of the background atmosphere during deposition can be varied to modify stoichiometry-related defects, and therefore achieve control of electrical and optical properties, while the total background pressure controls the material morphology at the nano- and mesoscale and thus the light scattering properties. This approach allows to tune electrical resistivity over a very wide range (10^-1 - 10^6 Ohm*cm), both in the in-plane and cross-plane directions. Optical transparency and haze can also be tuned by varying the stoichiometry and thickness of the nano-forests

Tuning of Electrical and Optical Properties of Highly Conducting and Transparent Ta-Doped TiO2 Polycrystalline Films

We present a detailed study on polycrystalline transparent conducting Ta-doped TiO2 films, obtained by room temperature pulsed laser deposition followed by an annealing treatment at 550°C in vacuum. The effect of Ta as a dopant element and of different synthesis conditions are explored in order to assess the relationship between material structure and functional properties, i.e. electrical conductivity and optical transparency. We show that for the doped samples it is possible to achieve low resistivity (of the order of 5×10-4 Ωcm) coupled with transmittance values exceeding 80% in the visible range, showing the potential of polycrystalline Ta:TiO2 for application as a transparent electrode in novel photovoltaic devices. The presence of trends in the structural (crystalline domain size, anatase cell parameters), electrical (resistivity, charge carrier density and mobility) and optical (transmittance, optical band gap, effective mass) properties as a function of the oxygen background pressures and laser fluence used during the deposition process and of the annealing atmosphere is discussed, and points towards a complex defect chemistry ruling the material behavior. The large mobility values obtained in this work for Ta:TiO2 polycrystalline films (up to 13 cm2V-1s-1) could represent a definitive advantage with respect to the more studied Nb-doped TiO2

Integrating MOOCs in physics preliminary undergraduate education: beyond large size lectures

In this paper, the authors discuss the effectiveness of MOOCs as part of a pedagogical strategy aimed at supporting Physics’ preliminary undergraduate students in large-size lectures. Our study is based on an experimental activity based on a blended course, which integrated a parallel MOOC delivered through the POK (PoliMi Open Knowledge, http://www.pok.polimi.it), the Politecnico di Milano’s MOOC portal. The blended model also delivered face-to-face activities that included intensive technology enhanced learning, like feedback based on clickers. Specifically, we introduce the several elements of the approach (the tutors’ pedagogy, the adoption of clickers, the diversity amongst learning groups) and its process of implementation. The findings in this study highlight that the integrated model is effective in terms’ of students’ learning both for small and large size lectures. More importantly, it was found that the students in large size lectures demonstrated similar or even better performance than students in a small size group. Moreover, the students in all sizes lectures showed higher satisfaction with the MOOCs’ against other factors adopted within the learning design