3,907 research outputs found
Reputation, Academic Experience, and Collaboration Returns from International Co-authorships
In recent years, the phenomenon of international co-authorships from emerging economies, especially Chinese scholars' academic collaborations, has become the focus of academic attention. Based on resource-based theory, taking the native scholars from mainland China with international co-authorships in 39 leading management journals as the sample, the article investigates the influence of individual scholars’ reputation and academic experience on their international collaboration returns. The empirical results show that, (1) Chinese native scholars could receive positive collaboration returns from international co-authorships; (2)the impact of academic experience of native scholars on collaboration returns depends on the measurement of “experience”. Early publishing experience in international journals positively influence collaboration returns, while the number of articles published in international journal does not have significant impact on collaboration returns. Keywords: Chinese native scholars, Collaboration returns from international co-authorships, Resources-based theory, Reputation, Academic experienc
Prior treated tuberculosis and mortality risk in lung cancer
BackgroundLung cancer is one of the leading causes of cancer death worldwide, and tuberculosis (TB) is a common pre-existing disease. However, there is scarce literature studying the mortality risk in patients with prior TB and subsequent lung cancer.MethodsWe recruited lung cancer patients from the Taiwan Cancer Registry from 2011 to 2015 and classified them into two groups according to presence or absence of prior TB. We then matched them in a ratio of 1:4 using the exact matching approach. The mortality risk within 3 years after diagnosis of lung cancer was analyzed and compared between these two groups.ResultsDuring the study period, 43,472 patients with lung cancer were recruited, and of these, 1,211 (2.79%) patients had prior TB. After matching, this cohort included 5,935 patients with lung cancer in two groups: patients with prior TB before lung cancer (n = 1,187) and those without (n = 4,748). After controlling for demographic factors and comorbidities, the patients with prior TB had increased adjusted hazard ratios of 1.13 (95% CI: 1.04–1.23) and 1.11 (1.02–1.21) for all-cause and cancer-specific 3-year mortality, respectively, compared to the lung cancer patients without prior TB. Duration between TB and lung cancer (<1 year vs. 1–3 years vs. >3 years) had no differences for mortality risk.ConclusionIn the present study, 2.79% patients with lung cancer had prior TB, which was associated with higher 3-year mortality after they developed lung cancer. The mortality risk with prior TB did not decrease even if >3 years passed before diagnosis of lung cancer
Oxygen Vacancy Induced Ferromagnetism in VO
{\it Ab initio} calculations within density functional theory with
generalized gradient approximation have been performed to study the effects of
oxygen vacancies on the electronic structure and magnetism in undoped
VO (). It is found that the introduction of oxygen
vacancies would induce ferromagnetism in VO with the magnetization
being proportional to the O vacancy concentration . The calculated
electronic structure reveals that the valence electrons released by the
introduction of oxygen vacancies would occupy mainly the neighboring V
-dominant band which then becomes spin-polarized due to intra-atomic
exchange interaction, thereby giving rise to the half-metallic ferromagnetism.Comment: To be published as a Letter in J. Phys. Soc. Japa
Genetic Variants in WNT2B and BTRC Predict Melanoma Survival
Cutaneous melanoma (CM) is the most lethal skin cancer. The Wnt pathway has an impact on development, invasion and metastasis of CM, thus likely affecting CM prognosis. Using data from a published genome-wide association study (GWAS) from The University of Texas M.D. Anderson Cancer Center, we assessed the associations of 19,830 common single-nucleotide polymorphisms (SNPs) in 151 Wnt pathway autosomal genes with CM-specific survival (CMSS) and then validated significant SNPs in another GWAS from Harvard University. In the single-locus analysis, 1,855 SNPs were significantly associated with CMSS at P T and BTRC rs61873997 G>A) that showed a predictive role in CMSS, with an effect-allele-attributed hazards ratio [adjHR of 1.99 (95% confidence interval (CI) = 1.41-2.81, P = 8.10E-05) and 0.61 (0.46-0.80, 3.12E-04), respectively]. Collectively, these variants in the Wnt pathway genes may be biomarkers for outcomes of CM patients, if validated by larger studies
Nocturnal CPAP improves walking capacity in COPD patients with obstructive sleep apnoea
BACKGROUND: Exercise limitation is an important issue in patients with chronic obstructive pulmonary disease (COPD), and it often co-exists with obstructive sleep apnoea (overlap syndrome). This study examined the effects of nocturnal continuous positive airway pressure (CPAP) treatment on walking capacity in COPD patients with or without obstructive sleep apnoea. METHODS: Forty-four stable moderate-to-severe COPD patients were recruited and completed this study. They all underwent polysomnography, CPAP titration, accommodation, and treatment with adequate pressure. The incremental shuttle walking test was used to measure walking capacity at baseline and after two nights of CPAP treatment. Urinary catecholamine and heart rate variability were measured before and after CPAP treatment. RESULTS: After two nights of CPAP treatment, the apnoea-hypopnoea index and oxygen desaturation index significantly improved in both overlap syndrome and COPD patients, however these changes were significantly greater in the overlap syndrome than in the COPD group. Sleep architecture and autonomic dysfunction significantly improved in the overlap syndrome group but not in the COPD group. CPAP treatment was associated with an increased walking capacity from baseline from 226.4 ± 95.3 m to 288.6 ± 94.6 m (P < 0.05), and decreased urinary catecholamine levels, pre-exercise heart rate, oxygenation, and Borg scale in the overlap syndrome group. An improvement in the apnoea-hypopnoea index was an independent factor associated with the increase in walking distance (r = 0.564). CONCLUSION: Nocturnal CPAP may improve walking capacity in COPD patients with overlap syndrome. TRIAL REGISTRATION: NCT0091426
Strong and broadly tunable plasmon resonances in thick films of aligned carbon nanotubes
Low-dimensional plasmonic materials can function as high quality terahertz
and infrared antennas at deep subwavelength scales. Despite these antennas'
strong coupling to electromagnetic fields, there is a pressing need to further
strengthen their absorption. We address this problem by fabricating thick films
of aligned, uniformly sized carbon nanotubes and showing that their plasmon
resonances are strong, narrow, and broadly tunable. With thicknesses ranging
from 25 to 250 nm, our films exhibit peak attenuation reaching 70%, quality
factors reaching 9, and electrostatically tunable peak frequencies by a factor
of 2.3x. Excellent nanotube alignment leads to the attenuation being 99%
linearly polarized along the nanotube axis. Increasing the film thickness
blueshifts the plasmon resonators down to peak wavelengths as low as 1.4
micrometers, promoting them to a new near-infrared regime in which they can
both overlap the S11 nanotube exciton energy and access the technologically
important infrared telecom band.Comment: 19 pages, 5 figures, main text followed by supporting informatio
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