Bounds on topological Abelian string-vortex and string-cigar from information-entropic measure

In this work we obtain bounds on the topological Abelian string-vortex and on the string-cigar, by using a new measure of configurational complexity, known as configurational entropy. In this way, the information-theoretical measure of six-dimensional braneworlds scenarios are capable to probe situations where the parameters responsible for the brane thickness are arbitrary. The so-called configurational entropy (CE) selects the best value of the parameter in the model. This is accomplished by minimizing the CE, namely, by selecting the most appropriate parameters in the model that correspond to the most organized system, based upon the Shannon information theory. This information-theoretical measure of complexity provides a complementary perspective to situations where strictly energy-based arguments are inconclusive. We show that the higher the energy the higher the CE, what shows an important correlation between the energy of the a localized field configuration and its associated entropic measure.Comment: 6 pages, 7 figures, final version to appear in Phys. Lett.

Ab initio study of electron transport in dry poly(G)-poly(C) A-DNA strands

The bias-dependent transport properties of short poly(G)-poly(C) A-DNA strands attached to Au electrodes are investigated with first principles electronic transport methods. By using the non- equilibrium Green's function approach combined with self-interaction corrected density functional theory, we calculate the fully self-consistent coherent I-V curve of various double-strand polymeric DNA fragments. We show that electronic wave-function localization, induced either by the native electrical dipole and/or by the electrostatic disorder originating from the first few water solvation layers, drastically suppresses the magnitude of the elastic conductance of A-DNA oligonucleotides. We then argue that electron transport through DNA is the result of sequence-specific short-range tunneling across a few bases combined with general diffusive/inelastic processes.Comment: 15 pages, 13 figures, 1 tabl

Effectiveness of unsupervised physical activity interventions in people with COPD: a systematic review and meta-analysis

No abstract available.publishe

Unsupervised physical activity interventions for people with COPD: a systematic review and meta-analysis

Introduction and objectives Unsupervised PA interventions might have a role in the management of chronic obstructive pulmonary disease (COPD) but their effectiveness is largely unknown. Thus, we aimed to identify and synthesise data on the effects of unsupervised PA interventions in people with COPD. Material and methods Databases were systematically searched in April 2020, with weekly updates until September 2021. Randomised controlled trials and quasi-experimental studies comparing unsupervised PA with usual care, were included. Primary outcomes were dyspnoea, exercise capacity and physical activity. The effect direction plot was performed to synthesise results. Meta-analysis with forest plots were conducted for the Chronic Respiratory Disease questionnaire – dyspnoea domain (CRQ-D), 6-minute walk distance (6MWD) and incremental shuttle walk distance (ISWD). Results Eleven studies with 900 participants with COPD (68±10 years; 58.8% male, FEV1 63.7±15.8% predicted) were included. All interventions were conducted at home, most with daily sessions, for 8-12 weeks. Walking was the most common component. The effect direction plot showed that unsupervised PA interventions improved emotional function, fatigue, health-related quality of life, muscle strength and symptoms of anxiety and depression. Meta-analysis showed statistical, but not clinical, significant improvements in dyspnoea (CRQ-D, MD=0.12, 95% CI 0.09-0.15) and exercise capacity, measured with 6MWD (MD=13.70, 95% CI 3.58-23.83). Statistical and clinical significant improvements were observed in exercise capacity, measured with ISWD (MD=58.59, 95% CI 5.79-111.39). None to minor adverse events and a high adherence rate were found. Conclusions Unsupervised PA interventions benefits dyspnoea and exercise capacity of people with COPD, are safe and present a high adherence rate. Unsupervised PA interventions should be considered for people with COPD who cannot or do not want to engage in supervised PA interventions or as a maintenance strategy of PA levels.publishe

Studies of CMB structure at Dec=40. II: Analysis and cosmological interpretation

We present a detailed analysis of the cosmic microwave background structure in the Tenerife Dec=+40 degrees data. The effect of local atmospheric contributions on the derived fluctuation amplitude is considered, resulting in an improved separation of the intrinsic CMB signal from noise. Our analysis demonstrates the existence of common structure in independent data scans at 15 and 33 GHz. For the case of fluctuations described by a Gaussian auto-correlation function, a likelihood analysis of our combined results at 15 and 33 GHz implies an intrinsic rms fluctuation level of 48^{+21}_{-15} uK on a coherence scale of 4 degrees; the equivalent analysis for a Harrison-Zel'dovitch model gives a power spectrum normalisation of Q_{rms-ps} = 22^{+10}_{-6} uK. The fluctuation amplitude is seen to be consistent at the 68% confidence level with that reported for the COBE two-year data for primordial fluctuations described by a power law model with a spectral index in the range 1.0 \le n \le 1.6. This limit favours the large scale CMB anisotropy being dominated by scalar fluctuations rather than tensor modes from a gravitational wave background. The large scale Tenerife and COBE results are considered in conjunction with observational results from medium scale experiments in order to place improved limits on the fluctuation spectral index; we find n=1.10 +/- 0.10 assuming standard CDM with H_{0}=50 kms^{-1}Mpc^{-1}.Comment: 10 pages LaTeX, including 8 PostScript figures. Accepted for publication in MNRA

Edge phonons in black phosphorus

Exfoliated black phosphorus has recently emerged as a new two-dimensional crystal that, due to its peculiar and anisotropic crystalline and electronic band structures, may have potentially important applications in electronics, optoelectronics and photonics. Despite the fact that the edges of layered crystals host a range of singular properties whose characterization and exploitation are of utmost importance for device development, the edges of black phosphorus remain poorly characterized. In this work, the atomic structure and the behavior of phonons near different black phosphorus edges are experimentally and theoretically studied using Raman spectroscopy and density functional theory calculations. Polarized Raman results show the appearance of new modes at the edges of the sample, and their spectra depend on the atomic structure of the edges (zigzag or armchair). Theoretical simulations confirm that the new modes are due to edge phonon states that are forbidden in the bulk, and originated from the lattice termination rearrangements.Comment: 15 pages, 4 figure

Unsupervised physical activity interventions for people with COPD: a systematic review

Effects of supervised physical activity (PA) are well-established in COPD however, the evidence about the effectiveness of unsupervised PA interventions in this population is still scarce. Thus, we aimed to identify and synthesise the effects of unsupervised PA interventions in people with COPD. A systematic search was conducted on Cochrane Library, PubMed, Scopus, Web of science and EBSCOhost databases, in April 2020. Randomised controlled trials and quasi-experimental studies comparing unsupervised PA with daily life, were included. Two independent reviewers selected the studies, extracted data and assessed the quality of evidence using the Quality Assessment Tool for Quantitative Studies. Effect sizes were calculated via Cohen’s d. 7 studies were included, 3 of moderate and 4 of weak quality. Most studies were conducted in a homebased setting (6/7), with the interventions lasting between 8-12 weeks (5/7). Frequencies of the interventions ranged from daily-2x/week (7/7). The components of interventions were: mobility (2/7), aerobic (2/7), strength (2/7), endurance (1/7) and lifestyle PA (2/7). Very small to huge effects [0.14 to 5.26] were found for exercise capacity (4/7) and health-related quality of life (HRQoL) [-2.25 to 0.19] (2/7). Very small to small effects were found for symptoms [-0.03 to 0.28] (2/7). Unsupervised PA interventions seem to be effective in increasing exercise capacity and HRQoL in people with COPD. Nevertheless, its application is still limited and highly heterogeneous thus, further studies, with robust methodologies, are needed to confirm our results and establish recommendations.publishe