Fruit and vegetable consumption and cardiovascular risk factors in older Chinese: The Guangzhou Biobank Cohort Study

published_or_final_versio

Nut consumption and cardiovascular risk in older Chinese: The Guangzhou Biobank Cohort Study

published_or_final_versio

Childhood secondhand smoke exposure and pregnancy loss in never smokers: The Guangzhou Biobank Cohort Study

published_or_final_versio

Effectiveness of varenicline and counseling for smoking cessation in an observational cohort study in China

published_or_final_versio

Coverage Analysis for Millimeter Wave Cellular Networks with Imperfect Beam Alignment

OAPA Millimeter wave (mmWave) communications is a promising approach to satisfy the increasing high data rate requirement of next generation mobile communications. This paper studies the downlink coverage performance of mmWave cellular networks with imperfect beam alignment. An enhanced antenna model is adopted to model the directional antenna beamforming pattern, in which the mainlobe beamwidth and directivity gain can be expressed as functions of the number of elements in the antenna array. After deriving the probability density function of the distance between mobile station (MS) and its serving base station (BS), the directivity gain with imperfect beam alignment is obtained as a discrete random variable. Then, a computationally tractable expression is obtained for the coverage probability of mmWave cellular networks.This generalized expression can be applied in different blockage regimes, e.g. general blockage regime (GBR), full-blockage regime (FBR) and non-blockage regime (NBR) with or without beam alignment errors. Numerical results show that small beam alignment errors will not deteriorate the coverage performance significantly, and the antenna array with the less number of elements provides higher robustness against the beam alignment errors. Moreover, when the beam alignment error is small enough, the coverage performance can be improved by increasing the BS intensity and the number of elements in the antenna array

Effectiveness of additional follow-up telephone counseling in a smoking cessation clinic in Beijing and predictors of quitting among Chinese male smokers

published_or_final_versio

The association between internet addiction and psychiatric co-morbidity: A meta-analysis

Background: This study evaluates the association between Internal Addiction (IA) and psychiatric co-morbidity in the literature.Methods: Meta-analyses were conducted on cross-sectional, case-control and cohort studies which examined the relationship between IA and psychiatric co-morbidity. Selected studies were extracted from major online databases. The inclusion criteria are as follows: 1) studies conducted on human subjects; 2) IA and psychiatric co-morbidity were assessed by standardised questionnaires; and 3) availability of adequate information to calculate the effect size. Random-effects models were used to calculate the aggregate prevalence and the pooled odds ratios (OR).Results: Eight studies comprising 1641 patients suffering from IA and 11210 controls were included. Our analyses demonstrated a significant and positive association between IA and alcohol abuse (OR = 3.05, 95% CI = 2.14-4.37, z = 6.12, P < 0.001), attention deficit and hyperactivity (OR = 2.85, 95% CI = 2.15-3.77, z = 7.27, P < 0.001), depression (OR = 2.77, 95% CI = 2.04-3.75, z = 6.55, P < 0.001) and anxiety (OR = 2.70, 95% CI = 1.46-4.97, z = 3.18, P = 0.001).Conclusions: IA is significantly associated with alcohol abuse, attention deficit and hyperactivity, depression and anxiety. © 2014 Ho et al.; licensee BioMed Central Ltd

Different definition of sarcopenia and mortality in cancer: A meta-analysis

Objectives: Sarcopenia has been an emerging theme in clinical oncology. Various definitions of sarcopenia have been proposed, but their prognostic performance have yet to be evaluated and compared. The aim of this meta-analysis is to comprehensively evaluate the performance of different cutoff definitions of sarcopenia in cancer mortality prognostication. / Methods: This is a meta-analysis. Cohort studies on lean mass and mortality published before December 20, 2017 were obtained by systematic search on PubMed, Cochrane Library, and Embase. Inclusion criteria were cohort studies reporting binary lean mass categorized according to clearly defined cutoffs, and with all-cause mortality as study outcome. Studies were stratified according to the cutoff(s) used in defining low lean mass. The cutoff-specific hazard ratios (HRs) and 95% confidence intervals (CIs) of low lean mass on cancer mortality were pooled with a random-effects model and compared. / Results: Altogether 81 studies that studied binary lean mass were included. The pooled HRs on cancer mortality using the 3 most used definitions were: 1.74 (95% CI, 1.46–2.07) using the definition proposed by International Consensus of Cancer Cachexia, 1.45 (95% CI, 1.21–1.75) using that by Martin, and 1.58 (95% CI, 1.35–1.84) using that by Prado. The associations between sarcopenia and cancer mortality using other definitions were all statistically significant, despite different estimates were observed. / Conclusions: The association of low lean mass with increased mortality was consistent across different definitions; this provides further evidence on the poorer survival in cancer patients with sarcopenia. However, further studies evaluating the performance of each definition are warranted

Morphology control and optical properties of SiGe nanostructures grown on glass substrate

With the rapid progress of nanotechnology, nanostructures with different morphologies have been realized, which may be very promising to enhance the performance of semiconductor devices. In this study, SiGe nanostructures with several kinds of configurations have been synthesized through a chemical vapor deposition process. By controlling growth conditions, different SiGe nanostructures can be easily tuned. Structures and compositions of the nanostructures were determined by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The optical properties of various SiGe nanostructures revealed some dependence with their morphologies, which may be suitable for solar cell applications. The control of the SiGe morphology on nanoscale provides a convenient route to produce diverse SiGe nanostructures and creates new opportunities to realize the integration of future devices