Thermal characteristics of oriental beech wood treated with some leaching resistant borates

It was aimed to investigate thermogravimetric analysis (TGA), differential-thermogravimetric (DTG), and differential-thermal analysis (DTA) of Oriental beech (Fagus orientalis L.) wood treated with some leaching resistant borates such as sodium tetraphenylborate (STPB) and phenylboronic acid (PBA). In this study; 0.25, 1.00, and 4.70 % aqueous solutions of borates were prepared. Results of the study indicated that pyrolysis occurred in three stages for STPB and PBA treated Oriental beech wood. Generally, while concentrations of the STPB and PBA increased, Ti and Tmax values of STPB and PBA treated wood specimens decreased. Residual char contents of STPB and PBA treated wood specimens for all concentrations were higher than untreated control specimen

Development of the Scale on Coping with Cyber Bullying towards AdolescentsErgenlere Yönelik Siber Zorbalıkla Başa Çıkma Ölçeği'nin geliştirilmesi

The purpose of this study was to develop a valid and reliable tool to measure high school students' coping behaviors which they exhibit when they are subjected to cyber bullying. The sample of the study was composed of 318 students studying at high schools in the province of Erzurum in the 2014-2015 educational years. The validity of the scale was analyzed via the construct validity and the criterion-related validity. For the construct validity, the exploratory and confirmatory factor analyses were made. As a result of the exploratory factor analysis, it was observed that the scale on coping with cyber bullying was composed of 17 items and 4 factors accounting for 61.36% of the total variance. Moreover, the construct validity of the scale on coping with cyber bullying was tested by the confirmatory factor analysis as well. As a result of the confirmatory factor analysis, the models of the scale were determined to be appropriate theoretically and statistically. In the criterion-related validity study, it was observed that there was a positive relationship between the scale on strategies to cope with bullying (SSCB) and the scale on coping with cyber bullying (SCCB). The reliability of the scales was calculated via the methods of internal consistency, split-half reliability and test-retest. Cronbach Alpha reliability coefficients for the sub-dimensions of the instrument ranged from .70 to .86. Split-half correlation coefficient for the sub-dimensions of the instrument ranged between .66 and .86. Moreover, the test-retest reliability for the SCCB varied between .68 and .83 These obtained values indicated the fact that the SCCB was a valid and reliable measurement tool. ÖzetBu araştırmanın amacı, ortaöğretim öğrencilerinin siber zorbalığa uğradıklarında gösterdikleri başa çıkma davranışlarını ölçmeye yönelik geçerli ve güvenilir bir ölçme aracı geliştirmektir. Araştırmanın örneklemini 2014-2015 öğretim yılında Erzurum ilinde ortaöğretim kurumlarında öğrenim gören 318 öğrenci oluşturmaktadır. Ölçeğin geçerliği, yapı geçerliği ve ölçüt bağıntılı geçerlikle incelenmiştir. Yapı geçerliği için açımlayıcı ve doğrulayıcı faktör analizi yapılmıştır. Açımlayıcı faktör analizi sonucunda siber zorbalıkla başa çıkma ölçeğinin toplam varyansın %61.36’sını açıklayan 17 madde ve 4 faktörden oluştuğu görülmüştür. Siber zorbalıkla başa çıkma ölçeğinin yapı geçerliği ayrıca doğrulayıcı faktör analizi ile test edilmiştir. Yapılan doğrulayıcı faktör analizi sonucunda ölçeğin modellerinin kuramsal ve istatistiksel olarak uygun olduğu belirlenmiştir. Ölçüt bağıntılı geçerlik çalışmasında zorbalıkla başa çıkma stratejileri ölçeği ile siber zorbalıkla başa çıkma ölçeği arasında anlamlı bir ilişkinin olduğu ortaya çıkmıştır. Ölçeklerin güvenirliği; iç tutarlık, iki yarı güvenirlik ve test-tekrar test yöntemleriyle hesaplanmıştır. Cronbach Alpha iç tutarlık katsayılarının ölçeğin alt boyutları için  .70-.86 arasında değiştiği görülmüştür. İki yarı test güvenirliği katsayılarının ölçeğin alt boyutları için .66-.86 arasında bulunduğu gözlenmiştir.  Ölçeğin test tekrar test güvenirlik katsayıları ölçek alt boyutları için .68-.83 arasında bulunmuştur. Bulunan bu değerler siber zorbalıkla başa çıkma ölçeğinin geçerli ve güvenilir bir ölçme aracı olduğunu göstermektedir

Mechanical properties of impregnated and heat treated oriental beech wood

The main purpose of this study was to investigate mechanical properties such as the modulus of rupture (MOR) and compression strength parallel to grain (CSPG) of impregnated and heat-treated Oriental beech (Fagus orientalis L.) wood. Some copper and boron containing impregnation chemicals such as Wolmanit CX-8 (WCX-8) and Celcure AC-500 (CAC500) were used. Wood specimens were impregnated 2% aqueous solution of the chemicals according to ASTM D1413-07e1 standard. The wood specimens were heated at 150 and 175 °C for 4 and 8 h, respectively. Results showed that both impregnation and heat treatment decreased the MOR and CSPG of Oriental beech wood. The MOR losses of Oriental beech after both treatments were higher than CSPG losses. The largest reduction of MOR and CSPG were observed with 51.5% and 15.5% for CAC-500 impregnated and heated at 175 °C for 8 h. Except for WCX-8 impregnation and heat treatment at 150 °C for 4 and 8 h, the MOR values of impregnated and heat-treated Oriental beech wood were lower than only heat-treated Oriental beech wood. It was also found that the CSPG values of impregnated and heat-treated Oriental beech wood were higher than only heat-treated Oriental beech wood, except for impregnation and heat treatment at 175 °C for 8 h

Effect of Continuous Positive Airway Pressure on Lipid Profiles in Obstructive Sleep Apnea: A Meta-Analysis

Background: Obstructive sleep apnea (OSA) is associated with dyslipidemia. However, the effects of continuous positive airway pressure (CPAP) treatment on lipid profiles are unclear. Methods: PubMed/Medline, Embase and Cochrane were searched up to July 2021. Randomized controlled trials (RCTs) of CPAP versus controls with >= 4 weeks treatment and reported pre- and post-intervention lipid profiles were included. Weighted mean difference (WMD) was used to assess the effect size. Meta-regression was used to explore the potential moderators of post-CPAP treatment changes in lipid profiles. Results: A total of 14 RCTs with 1792 subjects were included. CPAP treatment was associated with a significant decrease in total cholesterol compared to controls (WMD = -0.098 mmol/L, 95% CI = -0.169 to -0.027, p = 0.007, I-2 = 0.0%). No significant changes in triglyceride, high-density lipoprotein nor low-density lipoprotein were observed after CPAP treatment (all p > 0.2). Furthermore, meta-regression models showed that age, gender, body mass index, daytime sleepiness, OSA severity, follow-up study duration, CPAP compliance nor patients with cardiometabolic disease did not moderate the effects of CPAP treatment on lipid profiles (all p > 0.05). Conclusions: CPAP treatment decreases total cholesterol at a small magnitude but has no effect on other markers of dyslipidemia in OSA patients. Future studies of CPAP therapy should target combined treatment strategies with lifestyle modifications and/or anti-hyperlipidemic medications in the primary as well as secondary cardiovascular prevention models

New CagL amino acid polymorphism patterns of helicobacter pylori in peptic ulcer and non-ulcer dyspepsia

Background and Objectives: Helicobacter pylori infection is associated with chronic gastritis, ulcers, and gastric cancer. The H. pylori Type 4 secretion system (T4SS) translocates the CagA protein into host cells and plays an essential role in initiating gastric carcinogenesis. The CagL protein is a component of the T4SS. CagL amino acid polymorphisms are correlated with clinical outcomes. We aimed to study the association between CagL amino acid polymorphisms and peptic ulcer disease (PUD) and non-ulcer dyspepsia (NUD). Materials and Methods: A total of 99 patients (PUD, 46; NUD, 53) were enrolled and screened for H. pylori by qPCR from antrum biopsy samples. The amino acid polymorphisms of CagL were analyzed using DNA sequencing, followed by the MAFFT sequence alignment program to match the amino acid sequences. Results: Antrum biopsy samples from 70 out of 99 (70.7%) patients were found to be H. pylori DNA-positive. A positive band for cagL was detected in 42 out of 70 samples (PUD, 23; NUD, 19), and following this, these 42 samples were sequenced. In total, 27 different polymorphisms were determined. We determined three CagL amino acid polymorphism combinations, which were determined to be associated with PUD and NUD. Pattern 1 (K35/N122/V134/T175/R194/E210) was only detected in PUD patient samples and was related to a 1.35-fold risk (p = 0.02). Patterns 2 (V41/I134) and 3 (V41/K122/A171/I174) were found only in NUD patient samples and were linked to a 1.26-fold increased risk (p = 0.03). Conclusions: We observed three new patterns associated with PUD and NUD. Pattern 1 is related to PUD, and the other two patterns (Patterns 2 and 3) are related to NUD. The patterns that we identified include the remote polymorphisms of the CagL protein, which is a new approach. These patterns may help to understand the course of H. pylori infection.Istanbul Aydin University Scientific Research Projects Uni

Obstructive sleep apnea and its malajemente in patients with atrial fibrillation: An International Collaboration of Sleep Apnea Cardiovascular Trialists (INCOSACT) global survey of practicing cardiologists

Background: Among international cardiologists it is unclear whether equipoise exists regarding the benefit of diagnosing and managing obstructive sleep apnea (OSA) to improve atrial fibrillation (AF) outcomes and whether clinical practice and equipoise are linked. Methods: Between January 2019 and June 2020 we distributed a web-based 12-question survey regarding OSA and AF management to practicing cardiologists in 16 countries. Results: The United States, Japan, Sweden, and Turkey accounted for two-thirds of responses. 863 cardiologists responded; half were general cardiologists, a quarter electrophysiologists. Responses regarding treating OSA with CPAP to improve AF endpoints were mixed. 33% of respondents referred AF patients for OSA screening. OSA was diagnosed in 48% of referred patients and continuous positive airway pressure (CPAP) was prescribed for 59% of them. Nearly 70% of respondents believed randomized controlled trials (RCTs) of OSA treatment in AF patients were necessary and indicated willingness to contribute to such trials. Conclusions: There was no clinical equipoise among surveyed cardiologists; a majority expressed certainty that combined OSA and AF treatment is superior to AF treatment alone for improving AF outcomes. However, a minority of surveyed cardiologists referred AF patients for OSA testing, and while half of screened AF patients had OSA, CPAP was prescribed in little more than half of them, reflecting the view that better clinical trial evidence is needed to support this practice. Our results underscore the need for larger, multi-national prospective studies of OSA treatment and AF outcomes to inform more uniform society guideline recommendations

At-risk student teachers’ attitudes and aspirations as learners and teachers of mathematics

This study explored foundation phase first year student teachers’ perceptions about mathematics. The focus on their attitudes towards mathematics in two roles – (1) as learners of mathematics, based on their prior experiences at school and (2) as aspirant teachers of mathematics for children in the early grades. Data sources were students’ drawings/collages as well as written interpretations and elaborations of the drawings/collages. The findings indicated that participants had generally negative attitudes towards the learning of mathematics. Factors such as the transition from primary to high school, teacher qualities and mathematics-related anxiety contributed to the shaping of their attitudes. It was encouraging to note that over half the participants expressed positive attitudes in their roles as future teachers, with all expressing the desire to provide better mathematics experiences to their future learners.IBS