Impact of Menthol Smoking on Nicotine Dependence for Diverse Racial/Ethnic Groups of Daily Smokers

Introduction: The aims of this study were to evaluate whether menthol smoking and race/ethnicity are associated with nicotine dependence in daily smokers. Methods: The study used two subsamples of U.S. daily smokers who responded to the 2010–2011 Tobacco Use Supplement to the Current Population Survey. The larger subsample consisted of 18,849 non-Hispanic White (NHW), non-Hispanic Black (NHB), and Hispanic (HISP) smokers. The smaller subsample consisted of 1112 non-Hispanic American Indian/Alaska Native (AIAN), non-Hispanic Asian (ASIAN), non-Hispanic Hawaiian/Pacific Islander (HPI), and non-Hispanic Multiracial (MULT) smokers. Results: For larger (smaller) groups the rates were 45% (33%) for heavy smoking (16+ cig/day), 59% (51%) for smoking within 30 min of awakening (Sw30), and 14% (14%) for night-smoking. Overall, the highest prevalence of menthol smoking corresponded to NHB and HPI (\u3e65%), followed by MULT and HISP (31%–37%), and then by AIAN, NHW, and ASIAN (22%–27%) smokers. For larger racial/ethnic groups, menthol smoking was negatively associated with heavy smoking, not associated with Sw30, and positively associated with night-smoking. For smaller groups, menthol smoking was not associated with any measure, but the rates of heavy smoking, Sw30, and night-smoking varied across the groups. Conclusions: The diverse associations between menthol smoking and nicotine dependence maybe due to distinction among the nicotine dependence measures, i.e., individually, each measure assesses a specific smoking behavior. Menthol smoking may be associated with promoting smoking behaviors

Parameterized Littlewood-Paley operators with variable kernels on Hardy spaces and weak Hardy spaces

In this paper, by using the atomic decomposition theory of Hardy space and weak Hardy space, we discuss the boundedness of parameterized Littlewood-Paley operator with variable kernel on these spaces.Comment: 15 pages. arXiv admin note: text overlap with arXiv:1711.0961

Simultaneous attenuation of trace organics and change in organic matter composition in the hyporheic zone of urban streams

Trace organic compounds (TrOCs) enter rivers with discharge of treated wastewater. These effluents can contain high loads of dissolved organic matter (DOM). In a 48 h field study, we investigated changes in molecular composition of seven DOM compound classes (FTICR-MS) and attenuation of 17 polar TrOCs in a small urban stream receiving treated wastewater. Correlations between TrOCs and DOM were used to identify simultaneous changes in surface water and the hyporheic zone. Changes in TrOC concentrations in surface water ranged between a decrease of 29.2% for methylbenzotriazole and an increase of 152.2% for the transformation product gabapentin-lactam. In the hyporheic zone, only decreasing TrOC concentrations were observed, ranging from 4.9% for primidone to 93.8% for venlafaxine . TrOC attenuation coincided with a decline of molecular diversity of easily biodegradable DOM compound classes while molecular diversity of poorly biodegradable DOM compound classes increased. This concurrence indicates similar or linked attenuation pathways for biodegradable DOM and TrOCs. Strong correlations between TrOCs and DOM compound classes as well as high attenuation of TrOCs primarily occurred in the hyporheic zone. This suggests high potential for DOM turnover and TrOC mitigation in rivers if hyporheic exchange is sufficient.German Research Foundation (DFG)European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreementBattelle Memorial Institute for the U.S. Department of EnergyPeer Reviewe

Experimental design trade-offs for gene regulatory network inference: an in silico study of the yeast Saccharomyces cerevisiae cell cycle

Time-series of high throughput gene sequencing data intended for gene regulatory network (GRN) inference are often short due to the high costs of sampling cell systems. Moreover, experimentalists lack a set of quantitative guidelines that prescribe the minimal number of samples required to infer a reliable GRN model. We study the temporal resolution of data vs quality of GRN inference in order to ultimately overcome this deficit. The evolution of a Markovian jump process model for the Ras/cAMP/PKA pathway of proteins and metabolites in the G1 phase of the Saccharomyces cerevisiae cell cycle is sampled at a number of different rates. For each time-series we infer a linear regression model of the GRN using the LASSO method. The inferred network topology is evaluated in terms of the area under the precision-recall curve AUPR. By plotting the AUPR against the number of samples, we show that the trade-off has a, roughly speaking, sigmoid shape. An optimal number of samples corresponds to values on the ridge of the sigmoid

Development of a chemistry critical thinking test: initial reliability and validity studies

Background There are a myriad of commercially available tools which test critical thinking. These tests are designed for recruitment purposes and the context of these tests are often generic or abstract. A more accurate representation of student critical thinking may be obtained when students attach significance to the context of the test. Aims The aim of this investigation is to develop an instrument which can evaluate a chemistry student’s critical thinking ability at any stage of their study. This paper describes the development of a pilot test and reliability and validity studies associated with the test. Design and methods A chemistry critical thinking test was developed with thirty multiple choice items designed to assess ‘making assumptions’, ‘assessing arguments’, ‘making hypotheses’, ‘testing hypotheses’ and ‘drawing conclusions’. This test was administered to 1200 first year Monash University undergraduate chemistry students at the beginning of semester 1, 2016. 746 students completed the test which was analysed for internal reliability by using Cronbach’s alpha, t-tests and a correlation matrix of all test items. In conjunction with this, qualitative data has been collected from an academic focus group with respect to the content and construct validity of the test. Results A bell curve distribution of student test scores was obtained. Each sub-section of the test, for example ‘making assumptions’, reflected a similar distribution of scores. The internal reliability studies are still in progress. Students from this cohort have been invited to take part in a test-retest reliability study, a construct validity study against commercially available tools, and provide demographic data. Students will also participate in focus groups to collect qualitative data to further assess the content and construct validity of the test. These finding will be presented as part of this paper. Qualitative data from the academic focus group suggests that the some test items are dependent on chemistry knowledge. However, the focus group agree with how the constructs are assessed, and the relevance of the thought processes required to obtain the appropriate answer. Conclusions A chemistry critical thinking test has been developed and piloted. 746 first year participants obtained a bell curve distribution of scores and internal reliability data is pending. Qualitative data suggests the pilot test is dependent on chemistry knowledge in some areas. However the constructs of critical thinking are in alignment with the intention of the test

An undergraduate chemistry student view of critical thinking

KEYWORDS: critical thinking, qualitative analysis, chemistry, undergraduate, questionnaire BACKGROUND: In the field of chemistry critical thinking is commonly listed as graduate attribute in higher education qualifications. Much research has been conducted into the definition and pedagogy of critical thinking, and methods by which it can be developed in tertiary students of chemistry. AIM: This research sets out to define critical thinking from a student perspective and evaluate the importance students place on developing critical thinking skills in their studies. Furthermore, this study has sought to gain an understanding of which aspects of their chemistry education students perceived to be developing these skills. METHOD: A short open ended questionnaire was administered to a cohort of 800 first year, 300 second year and 90 third year Monash University undergraduate chemistry students at the beginning of semester 1, 2015. In total there were 522 respondents and the data was analysed via Nvivo using a grounded theory approach. RESULTS: Respondents identified critical thinking as an important skill to develop but only after skills such as ‘social skills’, ‘study skills’ and ‘communication’. Themes that emerged from the data with respect to a definition of critical thinking included ‘ability’, ‘analysis’, ‘decision making’, ‘information’, ‘lateral thought’, ‘objectivity’ and ‘problem solving’. Students indicated that they developed their critical thinking most often in a practical setting. Second year students in particular, highlighted inquiry-based activities as an opportunity to develop critical thinking. When asked to describe their confidence in developing their critical thinking, a bell curve distribution from ‘not very confident’ to ‘fairly confident’ was observed and approximately 15% of respondents cited difficulties and/or strategies associated with developing critical thinking, unrequested. These respondents cited a lack of guidance and content knowledge as the source of these difficulties. CONCLUSION: 522 undergraduate chemistry students were administered an open ended questionnaire regarding various aspects of critical thinking. Via qualitative analysis it emerged that students believed critical thinking to be important to develop during their studies but it was not their highest priority. Respondents defined critical thinking using words such as ‘analysis’, ‘objectivity’ and ‘problem solving’. The questionnaire suggests that students develop their critical thinking skill in practical setting and that difficulties arise in development due to poor guidance and limited content knowledge

Perceptions of preparedness for first year chemistry studies

The first-year of university is a challenging time where students are navigating and creating the balance between learning new academic skills and obtaining social and independent living skills. A successful transition into university is highly dependent on students’ academic preparedness. The findings of this research aim to demonstrate the impact perception of preparedness might have on student success in first-year chemistry units. We anticipate the interpretation of this data will be used to inform future teaching methods in Monash University. This presentation will showcase some of the findings from the analysis of pre- and post-semester survey responses and a series of teaching staff interviews and student focus groups. For example, of 846 first-year chemistry student responses to an online questionnaire, 88% had prior chemistry knowledge, but just 34% considered themselves prepared for university chemistry. It was also found that students with prior chemistry knowledge had a more positive perception towards university studies compared to students who have not had prior experience with chemistry. Open-ended responses revealed that difficulties with the mathematical aspects of chemistry was an important theme. The comparison between the online questionnaires and interviews produced some interesting findings juxtaposing perceptions of students and educators

How do you define creativity? A qualitative study of undergraduate chemistry students’ perspectives.

As technology continues to become more sophisticated, human thought in a professional setting will become more dependent on creativity. Employers around Australia identify creativity as a highly sought after attribute of recent graduate. To better understand how universities can develop STEM students’ creativity, an open-ended questionnaire was administered to first, second and third year undergraduate chemistry students at Monash University in semester one of 2019. Over 900 students completed the questionnaire which was processed through via NVivo. When asked to define creativity, students commonly identified themes of “originality and innovation” which aligned with the existing literature. Additional themes uncommon to the literature, such as “expression” and “problem solving” were also expressed. Within their studies, students identified self-directed activities such as the laboratories, assignments, and “teamwork activities” where opinions and thoughts are discussed most developed their creativity. Finally, students most commonly associated creativity with performing or creative arts in their extracurricular activities and suggested that these activities helped develop their problem solving, team work and experimentation within a STEM context. Once this data is triangulated with educators and employer perspectives, we anticipate an undergraduate teaching intervention can be designed to improve STEM students’ learning outcomes in creativity

Interaction Networks Are Driven by Community-Responsive Phenotypes in a Chitin-Degrading Consortium of Soil Microbes

Soil microorganisms provide key ecological functions that often rely on metabolic interactions between individual populations of the soil microbiome. To better understand these interactions and community processes, we used chitin, a major carbon and nitrogen source in soil, as a test substrate to investigate microbial interactions during its decomposition. Chitin was applied to a model soil consortium that we developed, “model soil consortium-2” (MSC-2), consisting of eight members of diverse phyla and including both chitin degraders and nondegraders. A multiomics approach revealed how MSC-2 community-level processes during chitin decomposition differ from monocultures of the constituent species. Emergent properties of both species and the community were found, including changes in the chitin degradation potential of Streptomyces species and organization of all species into distinct roles in the chitin degradation process. The members of MSC-2 were further evaluated via metatranscriptomics and community metabolomics. Intriguingly, the most abundant members of MSC-2 were not those that were able to metabolize chitin itself, but rather those that were able to take full advantage of interspecies interactions to grow on chitin decomposition products. Using a model soil consortium greatly increased our knowledge of how carbon is decomposed and metabolized in a community setting, showing that niche size, rather than species metabolic capacity, can drive success and that certain species become active carbon degraders only in the context of their surrounding community. These conclusions fill important knowledge gaps that are key to our understanding of community interactions that support carbon and nitrogen cycling in soil