DEMOGRAPHIC AND PSYCHOSOIAL CORRELATES OF WATERPIPE USE AMONG COLLEGE STUDENTS

The primary goal of this study was to characterize the role of demographic and psychosocial factors that influence waterpipe use among college students. Data were gathered in two stages that incorporated mixed methods. A series of 59 in-depth interviews were conducted with college students who were established waterpipe smokers. Participants identified socializing as the main reason to smoke waterpipe. Other reasons included social acceptance of waterpipes compared to cigarettes, peer influence, relaxation, perception of looking "cool" and physiological effects commonly referred to as "buzz." Perceptions that smoking waterpipe was safer and less addictive than smoking cigarettes were fairly common. The second stage involved a cross sectional survey (n=378), conducted among college students. The goal of the survey was to examine the association between demographic factors, background variables (involvement in Greek organizations, participation in athletics, and living arrangements), and psychosocial factors (perceived risks, resistance self efficacy, peer influence) in relation to waterpipe use among college students. Ever use of waterpipe smoking was reported by 59%. Students who had ever smoked cigarettes or cigars and had a best friend who smoked waterpipes were more likely to ever smoke waterpipe. Also, college students with high levels of resistance self-efficacy were less likely to ever smoke waterpipe. The secondary aim of the study was to develop an instrument that measured the social contexts of smoking waterpipe among college students. A pool of 50 items was administered to a purposive sample of college students (n=274), who were regular waterpipe users. Three factors emerged that accounted for a cumulative variance of 47% and possessed adequate reliability. These factors were labeled "social facilitation", "family/cultural influence", and "alternatives to cigarettes." The summed scores for the three social context subscales were examined across frequencies of waterpipe use. Those who reported smoking waterpipe at least on weekly basis reported significantly higher scores on social facilitation than the other two groups. Similar effects were observed for family/cultural influence; weekly smokers used waterpipe more frequently in a context of family/cultural influence than occasional smokers. Understanding patterns of correlates of waterpipe use among college students is critical in developing interventions

COVID-19 severity is associated with population-level gut microbiome variations

The human gut microbiome interacts with many diseases, with recent small studies suggesting a link with COVID-19 severity. Exploring this association at the population-level may provide novel insights and help to explain differences in COVID-19 severity between countries. We explore whether there is an association between the gut microbiome of people within different countries and the severity of COVID-19, measured as hospitalisation rate. We use data from the large (n = 3,055) open-access gut microbiome repository curatedMetagenomicData, as well as demographic and country-level metadata. Twelve countries were placed into two groups (high/low) according to COVID-19 hospitalisation rate before December 2020 (ourworldindata.com). We use an unsupervised machine learning method, Topological Data Analysis (TDA). This method analyses both the local geometry and global topology of a high-dimensional dataset, making it particularly suitable for population-level microbiome data. We report an association of distinct baseline population-level gut microbiome signatures with COVID-19 severity. This was found both with a PERMANOVA, as well as with TDA. Specifically, it suggests an association of anti-inflammatory bacteria, including Bifidobacteria species and Eubacterium rectale, with lower severity, and pro-inflammatory bacteria such as Prevotella copri with higher severity. This study also reports a significant impact of country-level confounders, specifically of the proportion of over 70-year-olds in the population, GDP, and human development index. Further interventional studies should examine whether these relationships are causal, as well as considering the contribution of other variables such as genetics, lifestyle, policy, and healthcare system. The results of this study support the value of a population-level association design in microbiome research in general and for the microbiome-COVID-19 relationship, in particular. Finally, this research underscores the potential of TDA for microbiome studies, and in identifying novel associations

Assessment of Nicotine Dependence and its Demographic Correlates among African American Smokers

Despite scientific evidence that smoking is highly addictive, little information is available on the prevalence of nicotine dependence among African American smokers. The primary objective of this study was to examine the associations between demographic variables, socioeconomic status, self reported smoking history and the level of nicotine dependence among African American smokers. This study was a cross-sectional secondary analysis of data collected during a randomized clinical trial from African American participants (n=206). The results showed that age of smokers, number of years of regular smoking, low education level and negative perception of ability to quit smoking were associated with high nicotine dependence. The multivariate analysis showed that those with negative perception of their ability to quit smoking had greater odds of having high nicotine dependence. The findings suggested that tailored interventions should include components that increase self efficacy among African American smokers depending on the level of nicotine dependence

A RAN Resource Slicing Mechanism for Multiplexing of eMBB and URLLC Services in OFDMA based 5G Wireless Networks

Enhanced mobile broadband (eMBB) and ultra-reliable and low-latency communications (URLLC) are the two main expected services in the next generation of wireless networks. Accommodation of these two services on the same wireless infrastructure leads to a challenging resource allocation problem due to their heterogeneous specifications. To address this problem, slicing has emerged as an architecture that enables a logical network with specific radio access functionality to each of the supported services on the same network infrastructure. The allocation of radio resources to each slice according to their requirements is a fundamental part of the network slicing that is usually executed at the radio access network (RAN). In this work, we formulate the RAN resource allocation problem as a sum-rate maximization problem subject to the orthogonality constraint (i.e., service isolation), latency-related constraint and minimum rate constraint while maintaining the reliability constraint with the incorporation of adaptive modulation and coding (AMC). However, the formulated problem is not mathematically tractable due to the presence of a step-wise function associated with the AMC and a binary assignment variable. Therefore, to solve the proposed optimization problem, first, we relax the mathematical intractability of AMC by using an approximation of the non-linear AMC achievable throughput, and next, the binary constraint is relaxed to a box constraint by using the penalized reformulation of the problem. The result of the above two-step procedure provides a close-to-optimal solution to the original optimization problem. Furthermore, to ease the complexity of the optimization-based scheduling algorithm, a low-complexity heuristic scheduling scheme is proposed for the efficient multiplexing of URLLC and eMBB services. Finally, the effectiveness of the proposed optimization and heuristic schemes is illustrated through extensive numerical simulations

Sources of Food Affect Dietary Adequacy of Inuit Women of Childbearing Age in Arctic Canada

Dietary transition in the Arctic is associated with decreased quality of diet, which is of particular concern for women of childbearing age due to the potential impact of maternal nutrition status on the next generation. The study assessed dietary intake and adequacy among Inuit women of childbearing age living in three communities in Nunavut, Canada. A culturally-appropriate quantitative food-frequency questionnaire was administered to 106 Inuit women aged 19-44 years. Sources of key foods, energy and nutrient intakes were determined; dietary adequacy was determined by comparing nutrient intakes with recommendations. The prevalence of overweight/obesity was >70%, and many consumed inadequate dietary fibre, folate, calcium, potassium, magnesium, and vitamin A, D, E, and K. Non-nutrient-dense foods were primary sources of fat, carbohydrate and sugar intakes and contributed >30% of energy. Traditional foods accounted for 21% of energy and >50% of protein and iron intakes. Strategies to improve weight status and nutrient intake are needed among Inuit women in this important life stage

Broadening the substrate scope of strictosidine synthases by site-directed mutagenesis

The condensation of ß-arylethylamines with carbonyl compounds (Pictet-Spengler reaction) is employed in the synthesis of tetrahydro-β-carboline and isoquinoline scaffolds which are common motifs in many naturally occurring alkaloids. These compounds exhibit a range of biological activities and are thus interesting targets for organic synthesis and medicinal chemistry. Nature’s equivalent to the Pictet-Spengler reaction is catalyzed by the so called Pictet-Spenglerases. Within this class of enzymes, strictosidine synthases (STRs, EC 4.3.3.2) have attracted attention [1-4]. These enzymes catalyse the formation of the 1,2,3,4-tetrahydro-β-carboline (S)-strictosidine, a key intermediate in the monoterpenoid indole alkaloid biosynthetic pathway in higher plants. Please click Additional Files below to see the full abstract

Memex Metadata (M2) for Reflective Learning

This paper reports on metadata research and development supporting memory and reflective learning that is being conducted as part of the Memex Metadata (M2) for Student Portfolios project, University of North Carolina at Chapel Hill. The paper reviews learning, memory, and reflective learning strategies; introduces the M2 project; presents a reflective learning scenario for a plant biology class; and reviews two metadata developments underlying the M2 project: 1) A context awareness framework (CAF), and 2) An extended metadata framework. The paper concludes with a brief discussion of future research activities.We would like to acknowledge Microsoft Research and UNC’s Information Technology Services for their support and sponsorship of this research