162 research outputs found

    Statistical analysis of particulate matter data in Doha, Qatar

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    Pollution in Doha is measured using passive, active and automatic sampling. In this paper we consider data automatically sampled in which various pollutants were continually collected and analysed every hour. At each station the sample is analysed on-line and in real time and the data is stored within the analyser, or a separate logger so it can be downloaded remotely by a modem. The accuracy produced enables pollution episodes to be analysed in detail and related to traffic flows, meteorology and other variables. Data has been collected hourly over more than 6 years at 3 different locations, with measurements available for various pollutants – for example, ozone, nitrogen oxides, sulphur dioxide, carbon monoxide, THC, methane and particulate matter (PM1.0, PM2.5 and PM10), as well as meteorological data such as humidity, temperature, and wind speed and direction. Despite much care in the data collection process, the resultant data has long stretches of missing values, when the equipment has malfunctioned – often as a result of more extreme conditions. Our analysis is twofold. Firstly, we consider ways to “clean” the data, by imputing missing values, including identified outliers. The second aspect specifically considers prediction of each particulate (PM1.0, PM2.5 and PM10) 24 hours ahead, using current (and previous) pollution and meteorological data. In this case, we use vector autoregressive models, compare with decision trees and propose variable selection criteria which explicitly adapt to missing data. Our results show that the regression tree models, with no variable transformations, perform the best, and that attempts to impute missing values are hampered by non-random missingness

    Re-thinking flexibility in higher education: A shared responsibility of students and educators

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    In recent years, there has been a growing recognition of the importance of flexibility in higher education as a key factor that can contribute to enhancing student learning and accessibility. However, flexibility has previously been investigated through an institutional lens that fails to consider those directly involved—students and educators. Moreover, the majority of current research regarding flexibility is based on anecdotal evidence and theoretical frameworks; therefore, evidence-based research is lacking. This plenary session is presented from a student perspective, who found that often, the parts of her identity that she took pride in—middle eastern background, gender, and hearing loss—were also the cause of her struggles. In conversations with other students, it was revealed that their diversity or life circumstances hindered their ability to pursue education. Flexibility was identified as key to enhancing their academic experience. Thus, the presenter decided to focus her fourth year thesis on a project that investigated students’ and educators’ experiences surrounding flexibility to inform future policies about effective flexible practices that accurately represent both groups. This session will highlight similarities and differences between students’ and educators’ experiences, barriers educators face when implementing flexibility, and a current misalignment in perceptions of flexibility between students and educators. Engaging in transparent and reciprocal open conversations can enhance the student-educator bond and solidify both groups’ sense of belonging. This study was approved by Western’s Non-Medical Research Ethics Board

    Respons Pemberian Coumarin Terhadap Produksi Mikro Tuber Planlet Kentang (Solanum Tuberosum L.) Varietas Granola

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    The objective of this experiment is to determine the response adding to the coumarin in to microtuber production of potato plantlets (Solanum tuberosum L.) varieties of granola. The research wasconducted at Tissue Culture Laboratory Experiment Berastagi where the surface level is atapproximately at ± 1340 m above sea level. The experiment was started on October 2013 untilFebruary 2014 using a completely randomized factorial design with two factors. The concentrations ofcoumarin was (0,000; 0,025; 0,050; and 0,075 gram/l) and the volume of coumarin was (30, 60, 90,120 ml). Parameters observed were the percentage of plantlets which produces micro tubers, thepercentage of plantlets were dead, the number of tubers on each micro planlet, the weight of tuberson each micro planlet, weight of each micro tuber, and diametres of tuber in each planlet. Theresults showed that adding of coumarin concentration into micro-tuber production of potatoplantlets was significantly affected the percentage of plantlets which produces micro tubers (1 BSAand 2 BSA) and the diameter of micro tubers of each plantlet. Adding of coumarin volume intomicro-tuber production of potato plantlets significantly affect on the percentage of plantlets whichproduces micro tubers (1 BSA and 2 BSA), the number of tubers on each micro planlet, the weightof tubers on each micro planlet, weight of each micro tuber, and diametres of tuber in each planlet

    Association of CHA2DS2-VASc score with successful recanalization in acute ischemic stroke patients undergoing endovascular thrombectomy

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    Introduction: The CHA2DS2-VASc (congestive heart failure, hypertension, age, diabetes mellitus, stroke, vascular disease and sex) score is a simple risk stratification algorithm to estimate stroke/thromboembolic risk in patients with non-valvular atrial fibrillation (AF). Higher pre-stroke CHA2DS2-VASc score is known to be associated with greater stroke severity and poorer outcomes. AF patients generally have higher CHA2DS2-VASc scores than non-AF patients. The Modified Thrombolysis in Cerebral Infarction (mTICI) score is the most widely used grading system to assess the result of recanalizing therapies in acute ischemic stroke (AIS). mTICI 2c and mTICI 3 are conventionally accepted as successful recanalization. Aim: We investigated whether pre-stroke CHA2DS2-VASc score is associated with mTICI recanalization score in AIS patients with and without AF undergoing percutaneous thrombectomy. Material and methods: One hundred fifty-nine patients with the diagnosis of AIS who were admitted within 6 h from symptom onset were included in the study (mean age: 65.7 ±12.9). All subjects underwent endovascular treatment. CHA2DS2-VASc scores of the participants were calculated. Subjects were grouped according to mTICI scores achieved after endovascular treatment. mTICI 2c and mTICI 3 were accepted as successful recanalization. Results: Successful reperfusion was observed in 130 (81.8%) of all patients who underwent endovascular treatment (mTICI flow ≄ 2c) and first-pass reperfusion was observed in 107 (67.3%) patients. When the patients with successful (mTICI flow ≄ 2c) and unsuccessful (mTICI flow ≀ 2b) reperfusion were divided into groups, no significant difference was observed between the patients in terms of comorbidities such as AF, hypertension, hyperlipidemia, coronary artery disease and cerebrovascular accident history. Patients with unsuccessful reperfusion were older than patients with successful reperfusion (71.4 ±11.2 vs. 64.5 ±13.01, p = 0.006), with a higher CHA2DS2-VASc score (4.1 ±1.5 vs. 3.04 ±1.6, p = 0.002). In addition, the duration of the procedure was longer in the unsuccessful reperfusion group (92.4 ±27.2 min vs. 65.0 ±25.1 min, p < 0.001). CHA2DS2-VASc score significantly correlated with successful recanalization (correlation coefficient; 0.243, p = 0.002). Multivariate logistic regression analysis revealed that only CHA2DS2-VASc score (OR = 1.43, 95% CI: 1.09-1.87, p = 0.006) and procedure time (OR = 1.03, 95% CI: 1.01-1.05, p < 0.001) were independent predictors of successful reperfusion. The receiver-operating characteristic (ROC) curve was used to determine the cut-off value for the CHA2DS2-VASc score that best predicts successful reperfusion. The optimal threshold was 3.5, with a sensitivity of 58.6% and specificity of 59.2% (area under the curve (AUC): 0.669, p = 0.005). Conclusions: For the first time in the literature, we investigated and demonstrated that pre-stroke CHA2DS2-VASc score was associated with success of recanalization as assessed with mTICI 2c and mTICI 3 in a cohort of AIS patients regardless of AF presence who underwent endovascular treatment. Our findings deserve to be tested with large scale long term studies

    Migraine headaches among university students using id migraine test as a screening tool

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    <p>Abstract</p> <p>Background</p> <p>Migraine is a significant health problem, especially for the young people, due to its frequency and accompanying morbidity, causing disability and loss of performance. In this study, our aim was to determine the prevalence of migraine headaches among university students in Edirne, a Turkish city.</p> <p>Methods</p> <p>In this cross-sectional and descriptive study, study population was composed of students registered to Trakya University in the academic year of 2008-2009. Out of these, 3694 of them accepted to participate. Participants who had two or more headaches in the last 3 months formed the headache group. Afterwards, two preliminary questions were applied to the headache group and participants with at least one affirmative response were asked to perform the validated ID-Migraineℱ test.</p> <p>Results</p> <p>The mean age of 3694 students participated in the study was 19.23 ± 1.84 (17-39 years), with adolescents:adult ratio being 2.5:1. 1613 students (43.7%) did have at least two headaches in the last three months. Migraine-type headache was detected in 266 subjects (7.2%) based on the ID-Migraineℱ test. Of the migraine group, 72 were male (27.1%) and 194 were female (72.9%). There was no significant difference in migraine prevalence between adolescent and adult age groups.</p> <p>Conclusions</p> <p>With a prevalence similar to adults, primary care physicians should be aware of the probability of migraine headaches in university students in order to maintain a successful school performance.</p

    Sexually Selected Infanticide in a Polygynous Bat

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    Background: Adult individuals of many species kill unrelated conspecific infants for several adaptive reasons ranging from predation or resource competition to the prevention of misdirected parental care. Moreover, infanticide can increase the reproductive success of the aggressor by killing the offspring of competitors and thereafter mating with the victimized females. This sexually selected infanticide predominantly occurs in polygynous species, with convincing evidence for primates, carnivores, equids, and rodents. Evidence for bats was predicted but lacking. Methodology/Principal Findings: Here we report the first case, to our knowledge, of sexually selected infanticide in a bat, the polygynous white-throated round-eared bat, Lophostoma silvicolum. Behavioral studies in a free-living population revealed that an adult male repeatedly attacked and injured the pups of two females belonging to his harem, ultimately causing the death of one pup. The infanticidal male subsequently mated with the mother of the victimized pup and this copulation occurred earlier than any other in his harem. Conclusions/Significance: Our findings indicate that sexually selected infanticide is more widespread than previously thought, adding bats as a new taxon performing this strategy. Future work on other bats, especially polygynous species in the tropics, has great potential to investigate the selective pressures influencing the evolution of sexually selecte

    A Worldwide Test of the Predictive Validity of Ideal Partner Preference-Matching

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    ©American Psychological Association, [2024]. This paper is not the copy of record and may not exactly replicate the authoritative document published in the APA journal. The final article is available, upon publication, at: [ARTICLE DOI]”Ideal partner preferences (i.e., ratings of the desirability of attributes like attractiveness or intelligence) are the source of numerous foundational findings in the interdisciplinary literature on human mating. Recently, research on the predictive validity of ideal partner preference-matching (i.e., do people positively evaluate partners who match versus mismatch their ideals?) has become mired in several problems. First, articles exhibit discrepant analytic and reporting practices. Second, different findings emerge across laboratories worldwide, perhaps because they sample different relationship contexts and/or populations. This registered report—partnered with the Psychological Science Accelerator—uses a highly powered design (N=10,358) across 43 countries and 22 languages to estimate preference-matching effect sizes. The most rigorous tests revealed significant preference-matching effects in the whole sample and for partnered and single participants separately. The “corrected pattern metric” that collapses across 35 traits revealed a zero-order effect of ÎČ=.19 and an effect of ÎČ=.11 when included alongside a normative preference-matching metric. Specific traits in the “level metric” (interaction) tests revealed very small (average ÎČ=.04) effects. Effect sizes were similar for partnered participants who reported ideals before entering a relationship, and there was no consistent evidence that individual differences moderated any effects. Comparisons between stated and revealed preferences shed light on gender differences and similarities: For attractiveness, men’s and (especially) women’s stated preferences underestimated revealed preferences (i.e., they thought attractiveness was less important than it actually was). For earning potential, men’s stated preferences underestimated—and women’s stated preferences overestimated—revealed preferences. Implications for the literature on human mating are discussed.Unfunde
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