687 research outputs found
Automation of current academic performance measurement based on the model of course assessment tools
The article proves the relevance of automating the process of students' current academic progress measurement, and represents a model of course assessment tools that allocates each assessment component to a particular competence acquired by students while studying the course. This model has served as basis for developing software for current academic performance measurement that involves the common database, as well as desktop and mobile applications. The collected data help to monitor the academic process and assess the level of competence acquisition
A more sustainable isothiocyanate synthesis by amine catalyzed sulfurization of isocyanides with elemental sulfur
Isothiocyanates (ITCs) are typically prepared using amines and highly toxic reagents such as thiophosgene, its derivatives, or CS. In this work, an investigation of a multicomponent reaction (MCR) using isocyanides, elemental sulfur and amines revealed that isocyanides can be converted to isothiocyanates using sulfur and catalytic amounts of amine bases, especially DBU (down to 2 mol%). This new catalytic reaction was optimized in terms of sustainability, especially considering benign solvents such as Cyrene™ or γ-butyrolactone (GBL) under moderate heating (40 °C). Purification by column chromatography was further optimized to generate less waste by maintaining high purity of the product. Thus, E-factors as low as 0.989 were achieved and the versatility of this straightforward procedure was shown by converting 20 different isocyanides under catalytic conditions, while obtaining moderate to high yields (34–95%)
Association of smoking and nicotine dependence with pre-diabetes in young and healthy adults.
INTRODUCTION: Several studies have shown an increased risk of type 2 diabetes among smokers. Therefore, the aim of this analysis was to assess the relationship between smoking, cumulative smoking exposure and nicotine dependence with pre-diabetes.
METHODS: We performed a cross-sectional analysis of healthy adults aged 25-41 in the Principality of Liechtenstein. Individuals with known diabetes, Body Mass Index (BMI) >35 kg/m² and prevalent cardiovascular disease were excluded. Smoking behaviour was assessed by self-report. Pre-diabetes was defined as glycosylated haemoglobin between 5.7% and 6.4%. Multivariable logistic regression models were done.
RESULTS: Of the 2142 participants (median age 37 years), 499 (23.3%) had pre-diabetes. There were 1,168 (55%) never smokers, 503 (23%) past smokers and 471 (22%) current smokers, with a prevalence of pre-diabetes of 21.2%, 20.9% and 31.2%, respectively (p <0.0001). In multivariable regression models, current smokers had an odds ratio (OR) of pre-diabetes of 1.82 (95% confidential interval (CI) 1.39; 2.38, p <0.0001). Individuals with a smoking exposure of <5, 5-10 and >10 pack-years had an OR (95% CI) for pre-diabetes of 1.34 (0.90; 2.00), 1.80 (1.07; 3.01) and 2.51 (1.80; 3.59) (p linear trend <0.0001) compared with never smokers. A Fagerström score of 2, 3-5 and >5 among current smokers was associated with an OR (95% CI) for pre-diabetes of 1.27 (0.89; 1.82), 2.15 (1.48; 3.13) and 3.35 (1.73; 6.48) (p linear trend <0.0001).
DISCUSSION: Smoking is strongly associated with pre-diabetes in young adults with a low burden of smoking exposure. Nicotine dependence could be a potential mechanism of this relationship
Early Life Risk Factors for Incident Atrial Fibrillation in the Helsinki Birth Cohort Study
Background-Early life risk factors are associated with cardiometabolic disease, but have not been fully studied in atrial fibrillation (AF). There are discordant results from existing studies of birth weight and AF, and the impact of maternal body size, gestational age, placental size, and birth length is unknown. Methods and Results-The Helsinki Birth Cohort Study includes 13 345 people born as singletons in Helsinki in the years 1934-1944. Follow-up was through national registries, and ended on December 31, 2013, with 907 incident cases. Cox regression analyses stratified on year of birth were constructed for perinatal variables and incident AF, adjusting for offspring sex, gestational age, and socioeconomic status at birth. There was a significant U-shaped association between birth weight and AF (P for quadratic term = 0.01). The lowest risk of AF was found among those with a birth weight of 3.4 kg (3.8 kg for women [85th percentile] and 3.0 kg for men [17th percentile]). High maternal body mass index (>= 30 kg/m(2)) predicted offspring AF; hazard ratio 1.36 (95% CI 1.07-1.74, P = 0.01) compared with normal body mass index ( Conclusions-High maternal body mass index during pregnancy and maternal height are previously undescribed predictors of offspring AF. Efforts to prevent maternal obesity might reduce later AF in offspring. Birth weight has a U-shaped relation to incident AF independent of other perinatal variables.Peer reviewe
Radon: a universal baseline indicator at sites with contrasting physical settings
The primary goal of World Meteorological Organisation Global Atmosphere Watch (WMO‐GAW) baseline stations is systematic global monitoring of chemical composition of the atmosphere, requiring a reliable, consistent and unambiguous approach for the identification of baseline air. Premier stations in the GAW baseline network span a
broad range of physical settings, from remote marine to high‐altitude continental sites, necessitating carefully tailored
site‐specific requirements for baseline sampling, data selection, and analysis. Radon‐222 is a versatile and unambiguous terrestrial tracer, widely‐used in transport and mixing studies. Since the majority of anthropogenic pollution sources also have terrestrial origins, radon has become a popular addition to the ‘baseline selection
toolkit’ at numerous GAW stations as a proxy for ‘pollution potential’. In the past, detector performance and postprocessing
methods necessitated the adoption of a relaxed (e.g. 100 mBq m‐3) radon threshold for minimal terrestrial influence, intended to be used in conjunction with other baseline criteria and analysis procedures, including wind speed, wind direction, particle number, outlier rejection and filtering. However, recent improvements in detector sensitivity, stability and post‐processing procedures have reduced detection limits below 10 mBq m‐3 at Cape Grim and to 25 mBq m‐3 at other baseline stations. Consequently, for suitably sensitive instruments (such as the ANSTO designed and built two‐filter dual‐flow‐loop detectors), radon concentrations alone can be used to unambiguously identify air masses that have been removed from terrestrial sources (at altitude or over ice), or in equilibrium
with the ocean surface, for periods of >2‐3 weeks (radon ≤ 40 mBq m‐3). Potentially, radon observations alone can thus provide a consistent and universal (site independent) means for baseline identification. Furthermore, for continental sites with complex topography and meteorology, where true ‘baseline’ conditions may never
occur, radon can be used to indicate the least terrestrially‐perturbed air masses, and provide a means by which to apply limits to the level of ‘acceptable terrestrial influence’ for a given application. We demonstrate the efficacy of the radon‐based selection at a range of sites in contrasting physical settings, including: Cape Grim (Tasmania), Cape Point (South Africa), Mauna Loa (Hawaii), Jungfraujoch (Switzerland) and Schneefernerhaus (Germany).Bureau of Meteorology and CSIRO Oceans and Atmosphere,Climate Science Centre
Planning and reporting of quality-of-life outcomes in cancer trials
BACKGROUND Information about the impact of cancer treatments on patients' quality of life (QoL) is of paramount importance to patients and treating oncologists. Cancer trials that do not specify QoL as an outcome or fail to report collected QoL data, omit crucial information for decision making. To estimate the magnitude of these problems, we investigated how frequently QoL outcomes were specified in protocols of cancer trials and subsequently reported. DESIGN Retrospective cohort study of RCT protocols approved by six research ethics committees in Switzerland, Germany, and Canada between 2000 and 2003. We compared protocols to corresponding publications, which were identified through literature searches and investigator surveys. RESULTS Of the 173 cancer trials, 90 (52%) specified QoL outcomes in their protocol, 2 (1%) as primary and 88 (51%) as secondary outcome. Of the 173 trials, 35 (20%) reported QoL outcomes in a corresponding publication (4 modified from the protocol), 18 (10%) were published but failed to report QoL outcomes in the primary or a secondary publication, and 37 (21%) were not published at all. Of the 83 (48%) trials that did not specify QoL outcomes in their protocol, none subsequently reported QoL outcomes. Failure to report pre-specified QoL outcomes was not associated with industry sponsorship (versus non-industry), sample size, and multicentre (versus single centre) status but possibly with trial discontinuation. CONCLUSIONS About half of cancer trials specified QoL outcomes in their protocols. However, only 20% reported any QoL data in associated publications. Highly relevant information for decision making is often unavailable to patients, oncologists, and health policymaker
Low-Field Phase Diagram of Layered Superconductors: The Role of Electromagnetic Coupling
We determine the position and shape of the melting line in a layered
superconductor taking the electromagnetic coupling between layers into account.
In the limit of vanishing Josephson coupling we obtain a new generic reentrant
low-field melting line. Finite Josephson coupling pushes the melting line to
higher temperatures and fields and a new line shape is found. We construct the low-field phase diagram including
melting and decoupling lines and discuss various experiments in the light of
our new results.Comment: 12 pages, 1 figure attached as compressed and uuencoded postscrip
Prospective Assessment of Sex-Related Differences in Symptom Status and Health Perception Among Patients With Atrial Fibrillation.
We prospectively assessed sex-specific differences in health perception, overall symptom status, and specific symptoms in a large cohort of patients with atrial fibrillation.
We performed a prospective multicenter observational cohort study of 1553 patients with atrial fibrillation. Patients completed questionnaires about personal characteristics, comorbidities, and symptoms on a yearly basis. Mean age was 70±11 years among women and 67±12 years among men. Health perception on a visual analogue scale ranging from 0 to 100 (with higher scores indicating better health perception) was significantly lower in women than in men (70 [interquartile range: 50-80] versus 75 [interquartile range: 60-85]; javax.xml.bind.JAXBElement@29592a5d <0.0001). More women than men had any symptoms (85.0% versus 68.3%; javax.xml.bind.JAXBElement@7ac0b4e4 <0.0001), palpitations (65.2% versus 44.4%; javax.xml.bind.JAXBElement@41229466 <0.0001), dizziness (25.6% versus 13.5%; javax.xml.bind.JAXBElement@61871784 <0.0001), dyspnea (35.7% versus 21.8%; javax.xml.bind.JAXBElement@16cc22b <0.0001), and fatigue (25.3% versus 19.1%; javax.xml.bind.JAXBElement@7ef43176 =0.006). At 1-year follow-up, symptoms decreased in both sexes but remained more frequent in women (49.1% versus 32.6%, javax.xml.bind.JAXBElement@2b200b6a <0.0001). In multivariable adjusted longitudinal regression models, female sex remained an independent predictor for lower health perception (ß=-4.8; 95% CI, -6.5 to -3.1; javax.xml.bind.JAXBElement@72c212bd <0.0001), any symptoms (odds ratio [OR]: 2.6; 95% CI, 2.1-3.4; javax.xml.bind.JAXBElement@15d8fb54 <0.0001), palpitations (OR: 2.6; 95% CI, 2.1-3.2; javax.xml.bind.JAXBElement@4af80718 <0.0001), dizziness (OR: 2.9; 95% CI, 2.1-3.9; javax.xml.bind.JAXBElement@61282e76 <0.0001), dyspnea (OR: 2.1; 95% CI, 1.6-2.8; javax.xml.bind.JAXBElement@31d9f14 <0.0001), fatigue (OR: 1.6; 95% CI, 1.2-2.2; javax.xml.bind.JAXBElement@51cdd678 =0.0008), and chest pain (OR: 1.8; 95% CI, 1.3-2.6; javax.xml.bind.JAXBElement@5b87db9e =0.001).
Women with atrial fibrillation have a substantially higher symptom burden and lower health perception than men. These relationships persisted after multivariable adjustment and during prospective follow-up
Self-employed in crisis:A study of the experiences of self-employed in Amsterdam during the corona crisis
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