Prevalence of dentine hypersensitivity among university students in Turkey

Background and Objective: Dentine hypersensitivity (DH) is a common clinical finding with a wide variation in prevalence values. There is lack of data on the prevalence of dentinal sensitivity in Turkish population. The aim of this study was to establish the prevalence of DH and to examine some associated factors such as initiating stimuli among university students in Kýrýkkale, Turkey.Materials and Methods: A cross-sectional survey was conducted among undergraduates of University of Kýrýkkale, Turkey. An electronic questionnaire was developed and distributed via e-mail to undergraduate students in Kýrýkkale University. Self-administered questionnaire elicited information on demography, self-reported dentinal sensitivity, thetrigger factor, professional treatment taken, and duration time. Test of significance was done with Chi square statistics. P<0.05 was considered as significant.Results: A total of 1463 responses were evaluated in this study. One hundred and twenty-four students were diagnosed as having DH, giving a prevalence figure of 8.4%. The prevalence of DH in females was significantly higher than that in males. The most common initiating factor was cold drinks. Tooth sensitivity was found to be common among hardtoothbrush users. About 46% of patients reported that they had not undergone any treatment for the discomfort and 35% reported having had some sort of treatment. Among the participants with dentinal sensitivity, 58.8% of the respondents reported that they use soft drinks occasionally. Approximately 64.2% of the patients claimed that DH was present for1–6 days and the majority (87%) of the patients with hypersensitive teeth experienced pain occasionally.Conclusion: The prevalence of DH among university students was 8.4%. DH is not a common problem in undergraduate university students

Antifungal and antibacterial effects of some acrocarpic mosses

In this study, the antifungal and antibacterial effect of 6 different  acrocarpous mosses were tested in vitro aganist 8 different  microorganisms. For the extraction, ethyl alcohol, methyl alcohol, acetone and chloroform were used as solvents. While the highest antimicrobial effect was seen in methyl alcohol extracts, extracts of chloroform showed the lowest level of antimicrobial effect. Grimmia anodon Bruch & Schimp. which is one of the acrocarp mosses used in this study, showed the highest activity in termsof the number of microorganism affected. Tortella tortuosa (Hedw.) Limpr. only has effect on Candida albicans ATCC 16231 strain. All the results were compared with standard antibiotic discs, ketoconazole (50 ìg), ampicillin (10 ìg), eritromycin (15 ìg) and vancomycin (30 ìg).Key words: Moss, acrocarpous, antimicrobial effect

Investigation of antimicrobial activity of some Turkish pleurocarpic mosses

In this study, the antimicrobial activities of different extracts from the five pleurocarpic mosses (Platyhypnidium riparioides (Hedw.) Dixon, Leucodon sciuroides (Hedw.) Schwägr., Hypnum cupressiforme Hedw., Homalothecium sericeum (Hedw.) Br.Eur., and Anomodon viticulosus (Hedw.) Hook & Taylor.) were tested aganist eight bacterial and fungal strains. For the extraction, four different solvents (ethyl alcohol, methyl alcohol, chloroform and acetone) were used. While methanolic extracts of P. riparioides showed the highest antibacterial effect against the Gram-negative bacterium Pseudomonas aeroginosa ATCC 27853, acetone extract of A. viticulosus showed the highest antifungal effect against the fungus Saccharomyces cerevisiae ATCC. All the results were compared with standard antibiotic discs: ketoconazole (50 μg), amphicillin (10 μg), eritromycin (15 μg), penicillin (10 μg) and vancomycin (30 μg).Key words: Moss, pleurocarpic, antimicrobial activity

Changes in cash holdings around the S&P 500 additions

We analyze the changes in cash holding policies of S&P 500 firms from before to after their inclusion in the index. One year after inclusion, their mean industry-adjusted cash holdings decline by nearly 32% from the year before inclusion. Several factors explain this decline. The precautionary motive for cash subsides due to these firms becoming more visible, less uncertain, and less constrained to raise cheap external capital. Corporate governance deteriorates after inclusion due to increased managerial entrenchment, which leads to a reduction in cash as suggested by the free cash flow hypothesis. Most index firms face diminishing investment opportunities and decreasing capital expenditures, which implies a lesser need for cash holdings related to the transaction motive. © 2013 Elsevier B.V

Sleep Induction by Mechanosensory Stimulation in Drosophila.

People tend to fall asleep when gently rocked or vibrated. Experimental studies have shown that rocking promotes sleep in humans and mice. However, the mechanisms underlying the phenomenon are not well understood. A habituation model proposes that habituation, a form of non-associative learning, mediates sleep induction by monotonous stimulation. Here, we show that gentle vibration promotes sleep in Drosophila in part through habituation. Vibration-induced sleep (VIS) leads to increased homeostatic sleep credit and reduced arousability, and can be suppressed by heightened arousal or reduced GABA signaling. Multiple mechanosensory organs mediate VIS, and the magnitude of VIS depends on vibration frequency and genetic background. Sleep induction improves over successive blocks of vibration. Furthermore, training with continuous vibration does not generalize to intermittent vibration, demonstrating stimulus specificity, a characteristic of habituation. Our findings suggest that habituation plays a significant role in sleep induction by vibration

Batch and continuous removal of heavy metals from industrial effluents using microbial consortia

Bio-removal of heavy metals, using microbial biomass, increasingly attracting scientific attention due to their significant role in purification of different types of wastewaters making it reusable. Heavy metals were reported to have a significant hazardous effect on human health, and while the conventional methods of removal were found to be insufficient; microbial biosorption was found to be the most suitable alternative. In this work, an immobilized microbial consortium was generated using Statistical Design of Experiment (DOE) as a robust method to screen the efficiency of the microbial isolates in heavy metal removal process. This is the first report of applying Statistical DOE to screen the efficacy of microbial isolates to remove heavy metals instead of screening normal variables. A mixture of bacterial biomass and fungal spores was used both in batch and continuous modes to remove Chromium and Iron ions from industrial effluents. Bakery yeast was applied as a positive control, and all the obtained biosorbent isolates showed more significant efficiency in heavy metal removal. In batch mode, the immobilized biomass was enclosed in a hanged tea bag-like cellulose membrane to facilitate the separation of the biosorbent from the treated solutions, which is one of the main challenges in applying microbial biosorption at large scale. The continuous flow removal was performed using fixed bed mini-bioreactor, and the process was optimized in terms of pH (6) and flow rates (1 ml/min) using Response Surface Methodology. The most potential biosorbent microbes were identified and characterized. The generated microbial consortia and process succeeded in the total removal of Chromium ions and more than half of Iron ions both from standard solutions and industrial effluents

Problematic online behaviors among adolescents and emerging adults: associations between cyberbullying perpetration, problematic social media use, and psychosocial factors

Over the past two decades, young people's engagement in online activities has grown markedly. The aim of the present study was to examine the relationship between two specific online behaviors (i.e., cyberbullying perpetration, problematic social media use) and their relationships with social connectedness, belongingness, depression, and self-esteem among high school and university students. Data were collected from two different study groups via two questionnaires that included the Cyberbullying Offending Scale, Social Media Use Questionnaire, Social Connectedness Scale, General Belongingness Scale, Short Depression-Happiness Scale, and Single Item Self-Esteem Scale. Study 1 comprised 804 high school students (48% female; mean age 16.20 years). Study 2 comprised 760 university students (60% female; mean age 21.48 years). Results indicated that problematic social media use and cyberbullying perpetration (which was stronger among high school students) were directly associated with each other. Belongingness (directly) and social connectedness (indirectly) were both associated with cyberbullying perpetration and problematic social media use. Path analysis demonstrated that while age was a significant direct predictor of problematic social media use and cyberbullying perpetration among university students, it was not significant among high school students. In both samples, depression was a direct predictor of problematic social media use and an indirect predictor of cyberbullying perpetration. However, majority of these associations were relatively weak. The present study significantly adds to the emerging body of literature concerning the associations between problematic social media use and cyberbullying perpetration

Fraction of exhaled nitric oxide is higher in liver transplant recipients than in controls from the general population: a cohort study

BackgroundFraction of exhaled nitric oxide with an expiratory flow of 50 mL/s (FENO50) is a biomarker of eosinophilic airway inflammation. Liver transplant recipients have an increased risk of pulmonary infections, but little is known about the burden of chronic pulmonary diseases in this group. We aimed to assess the prevalence of elevated FENO50 in liver transplant recipients and compare it to controls from the general population.MethodsFENO50 was measured in 271 liver transplant recipients from The Danish Comorbidity in Liver Transplant Recipients (DACOLT) study and 1,018 age- and sex-matched controls from The Copenhagen General Population Study (CGPS). Elevated FENO50 was defined as ≥25 or ≥50 parts per billion (ppb). The analyses were adjusted for known and suspected confounders.ResultsThe median age of the liver transplant recipients was 55 years (interquartile range (IQR) 46–64), and 58% were men. The liver transplant recipients had a higher median FENO50 than the controls [16 ppb (IQR 10–26) vs. 13 ppb (IQR 8–18.), p < 0.001]. Furthermore, the liver transplant recipients had a higher prevalence of elevated FENO50 (for FENO50 ≥25 ppb 27% vs. 11%, p < 0.001 and ≥50 ppb 4% vs. 2%, p = 0.02). The results were similar after adjusting for age, sex, smoking status, use of airway medication, and blood eosinophil counts [the adjusted odds ratio (OR) for FENO50 ≥25 ppb was 3.58 (95% CI: 2.50–5.15, p < 0.0001) and the adjusted OR for FENO50 ≥50 ppb was 3.14 (95% CI: 1.37–7.20, p = 0.007)].ConclusionThe liver transplant recipients had elevated FENO50, implying increased eosinophilic airway inflammation. The clinical impact of this finding needs further investigation