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Polymeric films composed of polyvinyl alcohol (PVA) with different percents of CeO2 and Cu2O were prepared using casting method to form PVA/(x) Cu2O (15-x) CeO2 composite at doping concentrations of (0, 1, 5, 7.5, 10, and 15 wt%). The addition of CeO2 and Cu2O affect the structural, morphological, vibrational, and optical properties of PVA film. The lattice parameters of the films were measured. PCC7 film with 15% Cu2O and 0% CeO2 in PVA polymer-matrix, is a suitable candidate to be utilized in UV-shielding for solar cell applications, because of its capability of blocking UV between 190 and 230 nm. The optical energy gap of films varies between 4.77 and 3.32 eV for the indirect transitions and between 4.84 and 3.83 eV for the direct transitions, hence the PCC5 with 7.5% Cu2O and 7.5% CeO2 has the lowest values of direct and indirect energy gaps, which attributed to the enhancement of electronic transitions correlated to the equal ratio of p type Cu2O and n type CeO2 doping. The average value of the refractive index nav was measured according to different approaches. Also, the nonlinear refractive index n2 was measured, it was found that PCC5 has the largest value of nav and n2. [ABSTRACT FROM AUTHOR]

The purpose of this cross-sectional observational study is to show how the perception of returnees' L2 can be changed in the digital era and how the massive spread of technology, among other factors, has eased an Arab (Saudi) returnee child's maintenance of English as an L2. The study discusses how technology allowed the returnee to continue to receive abundant L2 input, use the L2 daily, and interact with native speakers. The child was 9 months old when his family moved to the United States and was 6.2 years old when returned to Saudi Arabia. The study took place 5.4 years after their return when his age was 11.6 years old. A free conversation with the child, observation of online gaming, and an interview with parents were conducted to observe the child's L2 maintenance. The child demonstrated an intermediate level of fluency and produced non-verbal communication in free conversation and online gaming. The parents held positive attitudes toward bilingualism and English which was believed to have a great influence on the child's L2 maintenance. The study concludes that technology, parental attitudes, and personality and motivation have all contributed to the child's successful L2 maintenance. [ABSTRACT FROM AUTHOR]

Aim/Purpose The purpose of this study is to determine the impact of pre-listening activities on Arabic-speaking EFL learners' comprehension of spoken texts. Background This study aims to contribute to the current research and to increase our understanding about the effectiveness of pre-listening activities. Specifically, this study seeks to clarify some of the research in this area that seems to be incongruent. Methodology The study investigates two widely implemented activities in second language (L2) classrooms: vocabulary preteaching and content previewing. Ninety-three native-Arabic speaking EFL learners, whose proficiently levels were beginner, intermediate, or advanced, were randomly assigned to a control group or one of three experimental groups: the vocabulary-only (VO) group, content-only (CO) group, or vocabulary + content (VC) group. Each of the experimental groups received one of the treatments to determine which pre-listening activity was more effective and whether additional pre-listening activities yield additional comprehension. Listening comprehension of the aural text was measured by a test comprising 13 multiple-choice and true-false questions. Contribution The present study provided additional explanations regarding the long-standing contradicting results about vocabulary preteaching and content previewing. Findings The results showed that pre-listening activities had a positive impact on Arabicspeaking EFL learners' listening comprehension, with the VO group significantly increasing their scores on the posttest compared to those of the control or other groups. Vocabulary preteaching was particularly beneficial for more advanced learners. With regard to which pre-listening activity contributed the most to better listening comprehension, vocabulary preteaching was the most effective. Content previewing did not increase comprehension for the CO group and had no additional benefit for the VC group. Recommendations for Practitioners The results of this study suggest that providing L2 students with instruction on single words, multi-words, and idioms in the upcoming aural input has a positive impact on listening comprehension. The study provides positive evidence that vocabulary knowledge and word recognition play a major role in understanding L2 aural texts. It also provides support for the practice of vocabulary teaching in L2 listening classes. Recommendations for Researchers This paper recommends that researchers explore new pre-listening activities that have never studied. Future research should be extended to include other nations and contextual situations to extend our knowledge about the effect of pre-listening activities. As far as listening comprehension can only be achieved when listeners are attentive and engaged, the listening text should be interesting and the lexical coverage of the listening text should be appropriate for all participants. Future Research The results are to be interpreted carefully because they are limited by the students' L2 proficiency, demographic, and cultural backgrounds (i.e., first language (L1) proficiency, age, gender, Middle Eastern culture). Results might be quite different if the study was conducted with different populations who have different life and language learning experiences (Vandergrift & Baker, 2015). Therefore, the results of this study indicate there is much room for improvement and a need for further research. [ABSTRACT FROM AUTHOR]

Background: Migraine attacks can last for hours to days with severe pain which can affect the daily activities. Literature on quality of life of migraineurs is Saudi Arabia is scarce. This study aimed to assess the quality of life and its predictors among patients with migraine in Qassim region, Saudi Arabia. Methods: A cross-sectional study was conducted among patients with migraines in Qassim, Saudi Arabia. A self-administered questionnaire was distributed online among migraine patients that included; socio-demographic characteristics and an Arabic version of validated migraine-specific quality of life questionnaire (MSQ), version 2.1. Data analyses were performed in SPSS version 26. Results: A total of 320 patients with migraines participated in the study. The most common age group was 18–25 years (36.6%) with females were dominant (60.9%). According to the results of MSQ version 2.1, the mean ± SD scores of Role Restrictive (RR), Role Preventive (RP), and Emotion Function (EF) were 67.7 ± 19.7, 68.5 ± 20.6, and 70.6 ± 22.1, respectively. Statistical tests revealed that patients who reported less frequent migraine attacks, had better scores in RR, RP, and EF, while the use of paracetamol and painkillers for the treatment of headache were associated with lower scores in RR, RP, and EF. Conclusions: The quality of life among patients with migraines was generally moderate. Males demonstrated better QOL than females. Furthermore, patients who had less frequent migraine attacks exhibited better QOL than the others but working patients were likely to demonstrate poor QOL. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the most effective mode of input for L2 vocabulary learning by investigating three types of input: audiovisual input, audio input, and written input. Using a pretest-posttestdelayed posttest design, this study recruited 95 university EFL students who were randomly assigned to four groups. The same TV documentary was presented to each group in four different modes: viewing the documentary, listening to the documentary, reading the printed transcript, and a control condition in which no treatment was given. Vocabulary learning, which was operationalized as the receptive knowledge of the form-meaning connection of the target words was measured by checklist and multiple-choice tests. Two variables were considered in the investigation: prior vocabulary knowledge and the word frequency of occurrence. The findings suggest that participants learned vocabulary incidentally through viewing, listening, and reading. They also successfully retained gained vocabulary through the three modes of input. The study found no significant differences in vocabulary gains between viewing and reading on the posttests suggesting that vocabulary gain and retention are similar through these types of input modes. The study found a significant impact of prior vocabulary knowledge and frequency of occurrence on vocabulary learning. As the results suggest that viewing is as effective as reading, this study provides further support for the use of television in L2 learning. [ABSTRACT FROM AUTHOR]

COVID-19 has been associated with coagulation disorders which add further to the morbidity and mortality caused by the disease itself. Ischemic colitis can result from hypercoagulable states. In this report we present a rare case of ischemic colitis induced by COVID-19 in 27-year-old male. Patient presented with severe generalized abdominal pain. CT abdomen showed filling defects, absent enhancement indicating venous bowel ischemia. CT-angiograph revealed complete thrombosis of portal, splenic, superior and inferior mesenteric veins. Patient was shifted to intensive care unit and kept nothing per orum. He was given Heparin, tramadol and paracetamol intravenously. COVID-19 Reverse transcription-polymerase chain reaction (RT-PCR) was positive. He was then given Favipiravir through nasogastric (NG) tube. On 4th day NG was removed and patient was subsequently discharged on 9th day. COVID-19 may lead to hypercoagulable states and gastrointestinal complications. COVID-19 patients with gastrointestinal symptoms should be evaluated carefully for possible ischemia. [ABSTRACT FROM AUTHOR]

The purpose of this study is to examine the perceptions of EFL learners and teachers toward vlogs as a source of aural input for L2 listening practice inside and outside of classroom. A total of 389 EFL university students drawn from 29 listening/speaking classes and their teachers participated in this study. After four weeks of exploiting vlogs in the classroom, perceptions from students and teachers were collected through questionnaires, focus group-based discussion, and interviews. The findings of this study indicate that students found vlogs engaging, interesting, up-to-date while simultaneously being a source that will ensure learning. Teachers also had positive perceptions toward the use of vlogs in their classes to improve students' listening skill and vocabulary learning, as well as other aspects of the L2. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (DM) is a public health concern worldwide and an important cause of morbidity and mortality. Type 2 DM is associated with microvascular and macrovascular complications. Diabetic nephropathy (DN), which is characterized by proteinuria, is one of the most serious long-term microvascular complications of DM. The proportion of DN is increasing worldwide. DN is the leading cause of chronic kidney diseases and end-stage renal disease, which constitutes the major workload of dialysis centers worldwide. Microalbuminuria (MA) is the earliest sign of DN, so the early detection of MA and early control of diabetes retards the progression of DN. [ABSTRACT FROM AUTHOR]

Introduction: Risky behaviors are those that potentially expose people to harm, or significant risk of harm, which prevent them from reaching their potential in life and which can cause significant morbidity or mortality. Objectives: The objectives of the study were to determine the overall prevalence of risky behaviors among university students; to determine the prevalence of smoking, drifting, fast driving and physical inactivity among university students; and to determine the associations between such behavior and demographic characteristics. Materials and Methods: An observational cross-sectional study conducted in three colleges. The data were randomly collected from 340 students aged 18-30 years from February to March 2015 using a self-administered questionnaire in Arabic. The data were entered using SPSS v 22.0. Mean and standard deviation were calculated for quantitative variables, and frequency and percentages were computed for categorical variables. Chi-square or Fisher's Exact test, as appropriate, were used to test for statistical significance. Results: The overall prevalence of risky behaviors (smoking, drifting, fast driving, and physical inactivity) among students was 47.35%. Overall, 28% of the students were smokers, 25.2% were involved in drifting, 60.9% reported driving fast, and 66.4% were physically inactive. The age between 18-20 years was significantly associated with higher rates of drifting, fast driving, and physical inactivity. Conclusion: The prevalence of risky behaviors among university students was high. Physical inactivity and fast driving were the most common identified risky behaviors. Increasing awareness of these risks in the youth may significantly decrease related morbidities, complications, and even mortalities. [ABSTRACT FROM AUTHOR]

In order to identify the performance limitations of InGaAs/AlAs(Sb) quantum cascade lasers, experimental investigations of the temperature and pressure dependencies of the threshold current ( Ith) were undertaken. Using the theoretical optical phonon current ( Iph) and carrier leakage ( Ileak) to fit the measured threshold current at various pressures, we show that the electron scattering from the top lasing level to the upper L-minima gives rise to the increase in Ith with pressure and temperature. It was found that this carrier leakage path accounts for approximately 3% of Ith at RT and is negligible at 100 K. [ABSTRACT FROM AUTHOR]

Mid-infrared light emitting diodes based on the pentanary alloy GaInAsSbP have been engineered to provide a favourable band structure for the suppression of non-radiative Auger recombination which is dominant in narrow band gap III-V materials. Hydrostatic pressure measurements at room temperature and at 100 K were used to tune the band gap towards resonance with the spin-orbit band gap. Analysis of the resulting electroluminescence confirms that the non-radiative Auger recombination process involving the spin-orbit-split-off-band is suppressed under ambient conditions. [ABSTRACT FROM AUTHOR]