Multi-band Superconductivity in the Chevrel Phases SnMo6S8 and PbMo6S8

Sub-Kelvin scanning tunnelling spectroscopy in the Chevrel Phases SnMo6S8 and PbMo6S8 reveals two distinct superconducting gaps with Delta_1 = 3 meV, Delta_2 ~ 1.0 meV and Delta_1 = 3.1 meV, Delta_2 ~ 1.4 meV respectively. The gap distribution is strongly anisotropic, with Delta_2 predominantly seen when scanning across unit-cell steps on the (001) sample surface. The spectra are well-fitted by an anisotropic two-band BCS s-wave gap function. Our spectroscopic data are confirmed by electronic heat capacity measurements which also provide evidence for a twin-gap scenario.Comment: 5 pages, 4 figure

Phonon Mode Spectroscopy, Electron-Phonon Coupling and the Metal-Insulator Transition in Quasi-One-Dimensional M2Mo6Se6

We present electronic structure calculations, electrical resistivity data and the first specific heat measurements in the normal and superconducting states of quasi-one-dimensional M2Mo6Se6 (M = Tl, In, Rb). Rb2Mo6Se6 undergoes a metal-insulator transition at ~170K: electronic structure calculations indicate that this is likely to be driven by the formation of a dynamical charge density wave. However, Tl2Mo6Se6 and In2Mo6Se6 remain metallic down to low temperature, with superconducting transitions at Tc = 4.2K and 2.85K respectively. The absence of any metal-insulator transition in these materials is due to a larger in-plane bandwidth, leading to increased inter-chain hopping which suppresses the density wave instability. Electronic heat capacity data for the superconducting compounds reveal an exceptionally low density of states DEF = 0.055 states eV^-1 atom^-1, with BCS fits showing 2Delta/kBTc >= 5 for Tl2Mo6Se6 and 3.5 for In2Mo6Se6. Modelling the lattice specific heat with a set of Einstein modes, we obtain the approximate phonon density of states F(w). Deconvolving the resistivity for the two superconductors then yields their electron-phonon transport coupling function a^2F(w). In Tl2Mo6Se6 and In2Mo6Se6, F(w) is dominated by an optical "guest ion" mode at ~5meV and a set of acoustic modes from ~10-30meV. Rb2Mo6Se6 exhibits a similar spectrum; however, the optical phonon has a lower intensity and is shifted to ~8meV. Electrons in Tl2Mo6Se6 couple strongly to both sets of modes, whereas In2Mo6Se6 only displays significant coupling in the 10-18meV range. Although pairing is clearly not mediated by the guest ion phonon, we believe it has a beneficial effect on superconductivity in Tl2Mo6Se6, given its extraordinarily large coupling strength and higher Tc compared to In2Mo6Se6.Comment: 16 pages, 13 figure

Waterpipe Tobacco Smoking and Susceptibility to Cigarette Smoking Among Young Adults in the United States, 2012?2013

Introduction Waterpipe tobacco smoking, also known as hookah and shisha, has surged in popularity among young people in the United States. Waterpipe is also increasingly becoming the first tobacco product that young people try. Given the limited access to and limited portability of waterpipes, waterpipe smokers who become more nicotine dependent over time may be more likely to turn to cigarettes. This study examined the relationship between waterpipe tobacco smoking and susceptibility to cigarette smoking among young adults in the United States. Methods Using data from the 2012?2013 National Adult Tobacco Survey, a nationally representative sample of US adults, we reported rates of current waterpipe smoking and susceptibility to cigarette smoking by demographic characteristics and by use of other tobacco products among survey participants aged 18 to 24 years. Multivariable logistic regression was used to examine the relationship between current waterpipe smoking and susceptibility to cigarette smoking, defined as the lack of a firm intention not to smoke soon or within the next year. Results Of 2,528 young adults who had never established cigarette smoking, 15.7% (n = 398) reported being waterpipe smokers (every day or some days [n = 97; 3.8%] or rarely [n = 301; 11.9%]); 44.2% (176/398) of waterpipe smokers reported being susceptible to cigarette smoking. Those who smoked waterpipe rarely were 2.3 times as susceptible to cigarette smoking as those who were not current waterpipe smokers (OR = 2.3; 95% CI, 1.6?3.4). Conclusion Current waterpipe smoking is associated with susceptibility to cigarette smoking among young adults in the United States. Longitudinal studies are needed to demonstrate causality between waterpipe smoking and initiation of cigarette smoking

Guideline-discordant androgen deprivation therapy in localized prostate cancer: patterns of use in the medicare population and cost implications

Androgen deprivation therapy (ADT) in localized prostate cancer improves overall survival and is recommended by National Comprehensive Cancer Network guidelines in certain situations. However, ADT is without benefit in other situations and can actually cause harm. This study examines recent trends in the ADT use and quantifies the cost of guideline-discordant ADT

Addition of vardenafil into storage solution protects the endothelium in a hypoxia-reoxygenation model

OBJECTIVE: Based upon the well known protective effect of intracellular cyclic guanosine monophosphate (cGMP) accumulation, we tested the hypothesis that storage solution enriched with optimal concentration of the phosphodiestherase-5 inhibitor vardenafil could provide better protection of vascular grafts against reperfusion injury after long-term cold ischaemic storage. METHODS: Isolated thoracic aorta obtained from rats underwent 24-h cold ischaemic preservation in physiological saline or vardenafil (10(-11) M)-supplemented saline solution. Reperfusion injury was simulated by hypochlorite (200 muM) exposure for 30 minutes. Endothelium-dependent vasorelaxation was assessed, and histopathological and molecular-biological examination of the aortic tissue were performed. RESULTS: Compared with the control group, the saline group showed significantly attenuated endothelium-dependent maximal relaxation (Rmax) to acetylcholine after hypoxia-reoxygenation, which was significantly improved by vardenafil supplementation (Rmax control: 98 +/- 1%; saline: 48 +/- 6%; vardenafil: 75 +/- 4%; p < .05). Vardenafil treatment significantly reduced DNA strand breaks (control: 10.6 +/- 6.2%; saline: 72.5 +/- 4.0%; vardenafil: 14.2 +/- 5.2%; p < .05) and increased cGMP score in the aortic wall (control: 8.2 +/- 0.6; saline: 4.5 +/- 0.3; vardenafil: 6.7 +/- 0.6; p < .05). CONCLUSIONS: Our results support the view that impairment of intracellular cGMP signalling plays a role in the pathogenesis of the endothelial dysfunction induced by cold storage warm reperfusion, which can be effectively reversed by pharmacological phosphodiesterase-5 inhibition

SMEs’ innovativeness and technology adoption as downsizing strategies during COVID-19: the moderating role of financial sustainability in the tourism industry using structural equation modelling

This study aims to identify why firms, specifically SMEs in the hospitality and tourism industry, downsized during the recent global economic distress caused by COVID-19. This study applied a quantitative methodology by distributing online questionnaires to SME owners and managers who operate in the tourism industry of the UAE. We analysed the collected data using structural equation modelling. A total of 320 questionnaires were analysed using the PLS-SEM analytic tool. Our findings revealed that the investigated constructs, namely financial sustainability, SMEs’ innovativeness, and technology adoption predict the implementation of downsizing strategies during economic distress. However, financial sustainability failed to expedite SMEs’ innovativeness and technology adoption during this period. Therefore, the findings of this study show the impacts of financial strength, technology adoption, and innovativeness on implementing downsizing strategies, and provide suggested recommendations in light of the observed results

Gender differences in waterpipe tobacco smoking among university students in four eastern mediterranean countries

© 2020 Hamadeh R.R. et al. INTRODUCTION Males have a higher prevalence of waterpipe tobacco smoking (WTS) than females in most Eastern Mediterranean Region (EMR) countries, with a smaller gender gap than that of cigarette smoking. The objective of this study was to determine gender differences among university students with respect to WTS initiation, smoking behavior, tobacco flavors, and expenditure on WTS, in four EMR countries. METHODS A cross-sectional online survey was conducted based on convenient samples of ever waterpipe smokers among university students in four EMR countries (Egypt, Jordan, Occupied Palestinian Territories, and the United Arab Emirates) in 2016. The total samples included 2470 participants. Study participants were invited through flyers, university portals, emails and Facebook, followed by emails with links to the internet survey. RESULTS Females (80.4%) were more likely than males (66.4%, p\u3c0.001) to be in the younger age group (18–22 years) and they were less likely to be current waterpipe smokers (females, 60.0%; males 69.5%, p\u3c0.001). Two-thirds of students across both genders smoked their first waterpipe at the age of 15–19 years, with more females starting with family members. Over one-third of males and 14.9% of the females usually smoked ≥10 heads (p\u3c0.001). About half (46.6%) of females smoked for less than half an hour compared to 30.5% of males (p\u3c0.001). Only 1% of females smoked non-flavored tobacco compared to 11% of males (p\u3c0.001). There was a significant (p=0.05) positive correlation (r=0.808) with respect to tobacco flavor usually smoked between males and females with apple/double apple being the most popular. CONCLUSIONS There were gender differences in WTS in several aspects. The study has implications for educational establishments, tobacco control and women civil society groups, as well as policymakers

Harm perceptions of waterpipe tobacco smoking among university students in five Eastern Mediterranean Region countries: A cross-sectional study

© 2018 Abu-Rmeileh N. INTRODUCTION Waterpipe tobacco smoking (WTS) continues to be very common in the Eastern Mediterranean Region (EMR), partially because of cultural acceptance but also because of misconceptions of its harm. This paper aimed to describe the beliefs towards waterpipe harm of university students who smoked waterpipe in five EMR countries. METHODS This study was conducted in 2016 across five EMR countries: Egypt, Jordan, Occupied Palestinian Territories, Oman and United Arab Emirates (UAE). Participants were recruited from among university students in each country. Students’ characteristics, smoking behavior, flavor preference and knowledge of WTS harm were collected using an internet-based survey. Participants were included if they were ever waterpipe tobacco smokers and between 18 and 29 years of age. Bivariate analyses assessed variations in student-perceived WTS harm across the countries. Linear regression analysis was used to assess WTS perceived harm differences between students in the different countries. RESULTS A total of 2 544 university students participated from the five countries. Among ever smoking students, 66% reported WTS in the past 30 days, with the highest proportions (40%) from Occupied Palestinian Territories (OPT) and (41%) Jordan. Dual smoking of waterpipe and cigarettes was highest among students from Egypt. Most participants from the five countries had high level of perceived harm related to WTS during pregnancy. Less than 50% of the students believed that WTS could lead to the death of the smoker, can be harmful for non-smokers and have an addictive effect. Female students, those older than 22 years, and those who didn’t smoke waterpipe in the last 30 days significantly had a higher level of WTS perceived harm. Participating students believed that cigarettes are more addictive and contain more nicotine compared to waterpipe. CONCLUSIONS Misperceptions of waterpipe harm are common among university students in the five EMR countries. Immediate public health action is needed, including enforcement of waterpipe tobacco control regulations along with awareness campaigns

Significant CD4, CD8, and CD19 Lymphopenia in Peripheral Blood of Sarcoidosis Patients Correlates with Severe Disease Manifestations

BACKGROUND: Sarcoidosis is a poorly understood chronic inflammatory condition. Infiltration of affected organs by lymphocytes is characteristic of sarcoidosis, however previous reports suggest that circulating lymphocyte counts are low in some patients with the disease. The goal of this study was to evaluate lymphocyte subsets in peripheral blood in a cohort of sarcoidosis patients to determine the prevalence, severity, and clinical features associated with lymphopenia in major lymphocyte subsets. METHODOLOGY/PRINCIPAL FINDINGS: Lymphocyte subsets in 28 sarcoid patients were analyzed using flow cytometry to determine the percentage of CD4, CD8, and CD19 positive cells. Greater than 50% of patients had abnormally low CD4, CD8, or CD19 counts (p<4x10(-10)). Lymphopenia was profound in some cases, and five of the patients had absolute CD4 counts below 200. CD4, CD8, and CD19 lymphocyte subset counts were significantly correlated (Spearman's rho 0.57, p = 0.0017), and 10 patients had low counts in all three subsets. Patients with severe organ system involvement including neurologic, cardiac, ocular, and advanced pulmonary disease had lower lymphocyte subset counts as a group than those patients with less severe manifestations (CD4 p = 0.0043, CD8 p = 0.026, CD19 p = 0.033). No significant relationships were observed between various medical therapies and lymphocyte counts, and lymphopenia was present in patients who were not receiving any medical therapy. CONCLUSIONS/SIGNIFICANCE: Significant lymphopenia involving CD4, CD8, and CD19 positive cells was common in sarcoidosis patients and correlated with disease severity. Our findings suggest that lymphopenia relates more to disease pathology than medical treatment

U.S. Preventive Services Task Force Recommendations and Cancer Screening Among Female Medicare Beneficiaries

Background: Medicare covers several cancer screening tests not currently recommended by the U.S. Preventive Services Task Force (Task Force). In September 2002, the Task Force relaxed the upper age limit of 70 years for breast cancer screening recommendations, and in March 2003 an upper age limit of 65 years was introduced for cervical cancer screening recommendations. We assessed whether mammogram and Pap test utilization among women with Medicare coverage is influenced by changes in the Task Force's recommendations for screening