Direct and Heterodyne Detection of Microwaves in a Metallic Single Wall Carbon Nanotube

This letter reports measurements of microwave (up to 4.5 GHz) detection in metallic single-walled carbon nanotubes. The measured voltage responsivity was found to be 114 V/W at 77K. We also demonstrated heterodyne detection at 1 GHz. The detection mechanism can be explained based on standard microwave detector theory and the nonlinearity of the DC IV-curve. We discuss the possible causes of this nonlinearity. While the frequency response is limited by circuit parasitics in this measurement, we discuss evidence that indicates that the effect is much faster and that applications of carbon nanotubes as terahertz detectors are feasible

Exploring the Use of Numerical Relativity Waveforms in Burst Analysis of Precessing Black Hole Mergers

Recent years have witnessed tremendous progress in numerical relativity and an ever improving performance of ground-based interferometric gravitational wave detectors. In preparation for Advanced LIGO and a new era in gravitational wave astronomy, the numerical relativity and gravitational wave data analysis communities are collaborating to ascertain the most useful role for numerical relativity waveforms in the detection and characterization of binary black hole coalescences. In this paper, we explore the detectability of equal mass, merging black hole binaries with precessing spins and total mass M_T in [80,350]Msol, using numerical relativity waveforms and template-less search algorithms designed for gravitational wave bursts. In particular, we present a systematic study using waveforms produced by the MAYAKRANC code that are added to colored, Gaussian noise and analyzed with the Omega burst search algorithm. Detection efficiency is weighed against the orientation of one of the black-hole's spin axes. We find a strong correlation between the detection efficiency and the radiated energy and angular momentum, and that the inclusion of the l=2, m=+/-1,0 modes, at a minimum, is necessary to account for the full dynamics of precessing systems.Comment: 9 pages, 15 figure

Generalized phonon-assisted Zener tunneling in indirect semiconductors with non-uniform electric fields : a rigorous approach

A general framework to calculate the Zener current in an indirect semiconductor with an externally applied potential is provided. Assuming a parabolic valence and conduction band dispersion, the semiconductor is in equilibrium in the presence of the external field as long as the electronphonon interaction is absent. The linear response to the electron-phonon interaction results in a non-equilibrium system. The Zener tunneling current is calculated from the number of electrons making the transition from valence to conduction band per unit time. A convenient expression based on the single particle spectral functions is provided, enabling the numerical calculation of the Zener current under any three-dimensional potential profile. For a one dimensional potential profile an analytical expression is obtained for the current in a bulk semiconductor, a semiconductor under uniform field and a semiconductor under a non-uniform field using the WKB (Wentzel-Kramers-Brillouin) approximation. The obtained results agree with the Kane result in the low field limit. A numerical example for abrupt p - n diodes with different doping concentrations is given, from which it can be seen that the uniform field model is a better approximation than the WKB model but a direct numerical treatment is required for low bias conditions.Comment: 29 pages, 7 figure

The Influence of Physical Education on Self-Efficacy in Overweight Schoolgirls: A 12-Week Training Program

The purpose of this randomized controlled study was to investigate the impact of a 12- week physical education (PE) program on the self-efficacy of overweight schoolgirls. We randomly assigned 60 overweight schoolgirls (15–17 years) to either an experimental moderate to vigorous aerobic exercise (∼90 min, three times a week) group (n = 30) or a control group (CG) (n = 30) that received non-specific regular PE lessons with activities chosen by the curricular teacher mainly focused on team games and sports skills that aimed to achieve general psycho-physical wellness (∼90 min, three times a week). To assess the starting level of students and significant changes reached, at baseline and after training, a battery of standardized assessment motor tests and a psychometric scale (generalized self-efficacy scale, GES) were administered. At the end of the intervention, the experimental group reported a considerable decrease in body mass index (BMI) and a large improvement in self-efficacy (p < 0.001). No significant changes were found in the CG. The results suggested that the 12-week moderate to a vigorous aerobic exercise program is an effective weight loss intervention and a vehicle to promote a range of outcomes important to the qualitative growth of adolescents. In fact, it could provide a positive and significant impact on the self-efficacy of overweight schoolgirls

Branching on multi-aggregated variables

open5siopenGamrath, Gerald; Melchiori, Anna; Berthold, Timo; Gleixner, Ambros M.; Salvagnin, DomenicoGamrath, Gerald; Melchiori, Anna; Berthold, Timo; Gleixner, Ambros M.; Salvagnin, Domenic

The importance of lipidomic approach for mapping and exploring the molecular networks underlying physical exercise: A systematic review

Maintaining appropriate levels of physical exercise is an optimal way for keeping a good state of health. At the same time, optimal exercise performance necessitates an integrated organ system response. In this respect, physical exercise has numerous repercussions on metabolism and function of different organs and tissues by enhancing whole‐body metabolic homeostasis in response to different exercise‐related adaptations. Specifically, both prolonged and intensive physical exercise produce vast changes in multiple and different lipid‐related metabolites. Lipidomic technologies allow these changes and adaptations to be clarified, by using a biological system approach they provide scientific understanding of the effect of physical exercise on lipid trajectories. Therefore, this systematic review aims to indicate and clarify the identifying biology of the individual response to different exercise workloads, as well as provide direction for future studies focused on the body’s metabolome exercise‐related adaptations. It was performed using five databases (Medline (PubMed), Google Scholar, Embase, Web of Science, and Cochrane Library). Two author teams reviewed 105 abstracts for inclusion and at the end of the screening process 50 full texts were analyzed. Lastly, 14 research articles specifically focusing on metabolic responses to exercise in healthy subjects were included. The Oxford quality scoring system scale was used as a quality measure of the reviews. Information was extracted using the participants, intervention, comparison, outcomes (PICOS) format. Despite that fact that it is well‐known that lipids are involved in different sport‐related changes, it is unclear what types of lipids are involved. Therefore, we analyzed the characteristic lipid species in blood and skeletal muscle, as well as their alterations in response to chronic and acute exercise. Lipidomics analyses of the studies examined revealed medium‐ and long‐chain fatty acids, fatty acid oxidation products, and phospholipids qualitative changes. The main cumulative evidence indicates that both chronic and acute bouts of exercise determine significant changes in lipidomic profiles, but they manifested in very different ways depending on the type of tissue examined. Therefore, this systematic review may offer the possibility to fully understand the individual lipidomics exercise‐related response and could be especially important to improve athletic performance and human health

Effects of Nordic Walking Training on Anthropometric, Body Composition and Functional Parameters in the Middle-Aged Population

Nordic walking (NW) is an easy physical exercise that is usually proposed for clinical populations and for the elderly. The aim of the present study was to examine the effects of a period of NW training in a non-clinical middle-aged population on anthropometric, body composition and functional parameters. A pre-test/post-test study design was conducted on 77 participants: 56 women (72.7%, age 55.53 ± 9.73 years) and 21 men (27.3%, age 60.51 ± 8.15 years). The measurements were carried out with physical tests at the baseline and at the follow up. Participants did two weekly NW training sessions of about 60 min each. A questionnaire was administered to evaluate their feelings after the training period. Paired Students’ test was carried out to evaluate the pre–post differences, and the analysis of variance was performed to evaluate the questionnaire. Participants had significantly less stress and anxiety after the NW training. Body fat parameters showed a significant decrease, especially for women. Phase angle and strength of lower body presented a significant increase in both sexes after the training period. In conclusion, NW shows many potential benefits also for the nonclinical population and could be an important exercise to remain active and to maintain a good health condition

The graceful exit from the anomaly-induced inflation: Supersymmetry as a key

The stable version of the anomaly-induced inflation does not need a fine tuning and leads to sufficient expansion of the Universe. The non-stable version (Starobinsky model) provides the graceful exit to the FRW phase. We indicate the possibility of the inflation which is stable at the beginning and unstable at the end. The effect is due to the soft supersymmetry breaking and the decoupling of the massive sparticles at low energy.Comment: 10 pages, 2 figures using axodraw. Modified version. Discussion concerning the gravitational scale modified, the effect of massive particles in the last stage of inflation taken into accoun

The role of parental involvement in youth sport experience: perceived and desired behavior by male soccer players

Parents play a key role in the youth sports educational experience. They are responsible for the introduction of their children to physical or sporting education and their involvement has been associated with sport participation in early stages. The aims of this cross-sectional study were, first, to assess the perceived and desired parental involvement by children and, secondly, to exam-ine their satisfaction or dissatisfaction with any specific behavior. 80 male soccer players filled the Parental Involvement in Sport Questionnaire (PISQ) before or after a training session in presence of a coach. PISQ results revealed excessive active involvement and pressure, insufficient praise and understanding and satisfactory directive behavior from children’s parents. Our findings suggest that excessive parental involvement can cause pressure on children who would prefer parental participation characterized by praise and understanding. A balance between a supporting involvement without putting too much pressure is needed by the parents. To prevent burnout and dropout and to facilitate future practice, parents should be counseled (possibly by a sport educator) on how to positively support their children concerning their sport experience

Plantar pain is not always fasciitis

The case is described of a patient with chronic plantar pain, diagnosed as fasciitis, which was not improved by conventional treatment. Magnetic resonance imaging revealed flexor hallucis longus tenosynovitis, which improved after local glucocorticoid injection