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In this research, innovative green and sustainable solid polymer electrolytes (SPEs) based on plasticized methylcellulose/polyvinyl pyrrolidone/potassium carbonate (MC/PVP/K 2 CO 3 ) were examined. The MC/PVP/K 2 CO 3 SPE system with five distinct ethylene carbonate (EC) concentrations as a plasticizer was successfully designed. Frequency-dependent conductivity plots were used to investigate the conduction mechanism of the SPEs. Electrochemical potential window stability and the cation transfer number of the SPEs were studied via linear sweep voltammetry (LSV) and transference number measurement (TNM), respectively. Additionally, the structural behavior of the SPEs was analyzed using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), X-ray diffractometry (XRD), and differential scanning calorimetry (DSC) techniques. The SPE film complexed with 15 wt.% EC measured a maximum conductivity of 3.88 × 10 -4 Scm -1 . According to the results of the transference number examination, cations that record a transference number of 0.949 are the primary charge carriers. An EDLC was fabricated based on the highest conducting sample that recorded a specific capacitance of 54.936 Fg -1 at 5 mVs -1 .

The fabrication of Nano-based shielding materials is an advancing research area in material sciences and nanotechnology. Although bulky lead-based products remain the primary choice for radiation protection, environmental disadvantages and high toxicity limit their potentials, necessitating less costly, compatible, eco-friendly, and light-weight alternatives. The theme of the presented investigation is to compare the ionization radiation shielding potentialities of the lead acetate (LA), lead nitrate (LN), and bismuth nitrate (BN)-doped zinc oxide nanorods-based thin films (ZONRs-TFs) produced via the chemical bath deposition (CBD) technique. The impact of the selected materials' doping content on morphological and structural properties of ZONRs-TF was investigated. The X-ray diffractometer (XRD) analyses of both undoped and doped TFs revealed the existence of hexagonal quartzite crystal structures. The composition analysis by energy dispersive (EDX) detected the corrected elemental compositions of the deposited films. Field emission scanning electronic microscope (FESEM) images of the TFs showed highly porous and irregular surface morphologies of the randomly aligned NRs with cracks and voids. The undoped and 2 wt.% BN-doped TFs showed the smallest and largest grain size of 10.44 nm and 38.98 nm, respectively. The linear attenuation coefficient (µ) values of all the optimally doped ZONRs-TFs measured against the X-ray photon irradiation disclosed their excrement shielding potency. The measured µ values of the ZONRs-TFs displayed the trend of 1 wt.% LA-doped TF > 1 wt.% LN-doped TF > 3 wt.% BN-doped TF > undoped TFs). The values of μ of the ZONRs-TFs can be customized by adjusting the doping contents, which in turn controls the thickness and morphology of the TFs. In short, the proposed new types of the LA-, LN- and BN-doped ZONRs-TFs may contribute towards the development of the prospective ionization radiation shielding materials.

Background: The integration of patient encounters into the first year of the medical school curriculum is known to be of vital importance in the development of critical thinking and communication skills. We investigated whether exposure of first year medical students to patient encounters during a first year medical school neuroscience course result in a high level of motivation associated with the clinical encounter, and whether this high level of motivation translates to higher academic performance as measured by their performance on formative and summative examinations., Methods: First year medical students interacted with patients presenting with different neurological disorders in a small group informal session. Following the small group interactions with patients, students participated in a large group debriefing session involving discussions with peers, biomedical sciences faculty, and clinicians. Students then completed a survey designed to assess their motivation in correspondence with the Attention, Relevance, Confidence, and Satisfaction (ARCS) model of motivation. These results were then correlated with students' performance in the neuroscience examinations., Results: The total mean score was high for all categories of the ARCS model of motivation (4.26/5) and was highest for Relevance (4.46/5). When these motivation scores were correlated with students' performance on the formative and summative examinations, a significant positive correlation was found between motivation and performance on both the formative ( r = 0.85) and summative ( r = 0.95) neuroscience examinations., Conclusion: Encounters with patients presenting with neurological disorders during a first year medical neuroscience course result in a high level of motivation associated with the clinical encounter, and this was positively correlated with their academic performance., Competing Interests: Conflict of InterestThe authors declare that they have no conflict of interest., (© International Association of Medical Science Educators 2020.)

Purpose: Many countries and institutions have a fixed passing score of 60%. For example, this is a national policy in all Saudi universities where students at all levels must score 60% or higher to pass courses. The purpose of this study is to broaden the scope of standard-setting applications, using data from five major dental courses (Endodontics, Operative, Removable and Fixed Prosthodontics, and Pedodontics) in the 5th dental academic year for two consecutive years to determine the cut-off scores., Methodology: Four expert raters conducted Angoff's method on final examinations of five dental courses to determine the cut-off scores for the two academic years (2015, and 2016). Cohort size of 2015 was 120 students, whilst that of 2016 was 142 students. The study was conducted at the faculty of Dentistry, at King Abdulaziz University (KAU) from December 2017 to June 2018., Results: All five dental courses yielded different cut-off scores than the fixed 60%. The cut-off scores for 2015 and 2016 examinations were 59.15%, 63.75% for Removable Prosthodontics, 51.86%, 53.75% for Fixed Prosthodontics, 47.42%, 50.5% for Pedodontics, 74.22%, 74.31% for Endodontics and 58%, 55.55% for Operative Dentistry., Conclusion: Angoff method yielded different cut-off scores than the fixed 60% passing score currently used by the dental school, yielding a difference in pass-fail rates by as much as a staggering 41%. This finding provides support to use evidence-based standard-setting methods to determine the cut-off score for the courses in Dentistry programme., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

A new series of N'-substituted benzylidene-2-(4-oxo-2-phenyl-1,4-dihydroquinazolin-3(2H)-yl)acetohydrazide ( 5a-5h ) has been synthesized, characterized by FT-IR, NMR spectroscopy and mass spectrometry and tested against human monoamine oxidase (MAO) A and B. Only (4-hydroxy-3-methoxybenzylidene) substituted compounds gave submicromolar inhibition of MAO-A and MAO-B. Changing the phenyl substituent to methyl on the unsaturated quinazoline ring ( 12a-12d ) decreased inhibition, but a less flexible linker ( 14a-14d ) resulted in selective micromolar inhibition of hMAO-B providing insight for ongoing design., Competing Interests: There are no conflicts to declare., (© 2020 The Authors.)

Objectives: In this study, eye lens dose measurements were performed using two anthropomorphic phantoms simulating the cardiologist and patient during interventional procedures., Background: Interventional procedures known as areas with high potential risk and the cardiologists can receive relatively high doses to their eyes., Methods: This study was comprised of both phantom and computer simulations. Thermoluminescent dosimeters (TLDs) and mEyeDose_X tool were used to measure and calculate eye lens doses for the cardiologist. 144 TLDs measurements were performed using cardiac protocol for three angiographic projections: anterior-posterior (AP), left anterior oblique 90° (LAO90) and left anterior oblique 45° with cranial 30° (spider) angulations. All cine and fluoroscopy modes including the projections used in this study performed with and without protection tools., Results: The annual equivalent doses with protective tools using mEyeDose_X were found to be 1.831 and 1.424 mSv/year, whereas the values using phantom were found to be 2.204 and 1.802 mSv/year for the lens of lift and right eye respectively., Conclusion: The annual doses reported in this study are almost comparable to other studies performed on interventional cardiology (IC) procedures. The highest dose rate in the lens was 20.21 ± 0.015 mSv/h without protective tools in cine mode for spider projection. Cardiologists may therefore easily exceed the lens dose limit if protective tools are not used., Competing Interests: Declaration of competing interest None., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Implementing educational activities, such as a wet lab with cadaveric brain dissection, is known to have a direct impact on medical students' motivation. These activities demonstrate the clinical relevance of concepts taught in the classroom setting. The correlation between motivation and academic performance is not clear. First year medical students participated in wet lab activities. The wet lab included cadaveric dissection of the surface and internal anatomy of the brain, as well as discussions facilitated by the neuroscience faculty and clinicians. Discussions were centered around the clinical relevance of the neuroanatomical features dissected during the wet laboratory activities. Following completion of the laboratory activities, students completed a survey, which was used to assess the students' motivation for learning neuroanatomy based on the Attention, Relevance, Confidence, Satisfaction (ARCS) model of motivation. These results were then correlated with performance on a laboratory examination that tested three-dimensional and cross-sectional knowledge of neuroanatomy and practical skills including the use of imaging techniques. The total mean score of motivation was generally high for all categories of ARCS model of motivation (4.26/5) and was highest for Relevance (4.46/5). When these results were correlated with students' performance on the lab examination, a positive correlation between students' motivation and lab examination scores was found (R 2 = 0.877). Implementation of the neuroanatomy cadaveric dissection lab led to increased student motivation, which was positively correlated with students' academic performance. Clin. Anat. 32:128-135, 2019. © 2019 Wiley Periodicals, Inc., (© 2019 Wiley Periodicals, Inc.)

Objectives: The objectives of this study were to investigate the occurrence of oxidative stress, status of protective antioxidants enzymes, inflammatory biomarkers, and some metabolic health variables in the blood and to compare the results between those of the normal controls and obese patients submitted to sleeve gastrectomy-induced weight loss over a 1-year follow-up period., Materials and Methods: A prospective study was conducted in Aseer Central Hospital and Abha Private Hospital in the Kingdom of Saudi Arabia from January 2012 to January 2013 on 50 normal (BMI = 22-25 kg/m 2 ) control subjects and 50 obese (BMI = 45-50 kg/m 2 ) patients. A subset of 20 men and 80 women patients, aged 20-45 years, was included. The systemic blood cell counts were determined by Beckman Coulter UniCel analyzer. The occurrence of oxidative stress, the status of antioxidant enzyme system in the blood, levels of serum hepatic enzymes, cardiovascular risk factors, and serum sodium, potassium, copper, and zinc levels were determined by spectrophotometric procedures. The concentration of TSH and T 4 were analyzed by Siemens Immunoassay System., Results: Group 1 (Obese: preoperative) This group compared with the normal controls exhibited significant (p < 0.05) increase in inflammatory biomarkers, a significant (p < 0.05) rise in hepatic enzymes, a significant (p < 0.05) decrease in serum total bilirubin. Concentration of serum total cholesterol (TC), triacylglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and fasting blood glucose(FBG) were significantly (p < 0.05) increased, but HDL cholesterol (HDL-C) was significantly depleted (p < 0.05). Serum urea and creatinine contents were significantly (p < 0.05) decreased. Serum copper and zinc levels were significantly (p < 0.05) increased. Group 2: Sleeve Gastrectomy Surgery (Obese: postoperative) This group compared with the obese group, preoperatively, demonstrated a profound reduction in body weight (-32%) as well as in BMI (-29%). Serum malondialdehyde, a stress index, was significantly (p < 0.001) inhibited and conversely, activities of antioxidant enzymes: superoxide dismutase(Cu-Zn SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PDH), and vitamin C, were remarkably (p < 0.001) increased. Furthermore, remarkable improvements in deranged metabolic variables approaching normality were discernible. Inflammatory biomarkers in the blood and hepatic enzymes in serum were significantly (p < 0.001) decreased. Levels of TC, TG, LDL-C, FBG, and HDL-C in serum exhibited significant (p < 0.05) reductions, a reversal toward normality. Serum albumin and total bilirubin concentrations were significantly increased (p < 0.001). Serum sodium, potassium, copper, zinc, and TSH levels were significantly (p < 0.001) decreased., Conclusions: Obesity is a chronic disease of multifactorial origin and resulted in perturbations of whole body metabolism in this study. It is thus likely that this imbalance was associated with an inhibition in protective antioxidants and occurrence of oxidative stress. The staging concept of sleeve gastrectomy is a safe and effective approach with remarkable efficacy in sustaining weight loss and bringing back normal metabolism of variables in tissues over a 1-year follow-up period.

Understanding how culture may influence biodiversity is fundamental to ensure effective conservation, especially when the practice is local but the implications are global. Despite that, little effort has been devoted to documenting cases of culturally-related biodiversity loss. Here, we investigate the cultural domestication of the European goldfinch (Carduelis carduelis) in western Maghreb (Morocco, Algeria and Tunisia) and the effects of long-term poaching of wild populations (1990-2016) on range distribution, socio-economic value, international trading and potential collateral damage on Afro-Palearctic migratory birds. On average, we found that the European goldfinch lost 56.7% of its distribution range in the region which led to the increase of its economic value and establishment of international trading network in western Maghreb. One goldfinch is currently worth nearly a third of the average monthly income in the region. There has been a major change in poaching method around 2010, where poachers started to use mist nets to capture the species. Nearly a third of the 16 bird species captured as by-catch of the European goldfinch poaching are migratory, of which one became regularly sold as cage-bird. These results suggest that Afro-Palearctic migratory birds could be under serious by-catch threat.

Background: IGF-1 plays a role in the growth of multiple tumor types, including pancreatic cancer. IGF-1 also serves as a growth factor for muscle. The impact of therapeutic targeting of IGF-1 on muscle mass is unknown., Methods: We evaluated muscle mass at L3 in patients enrolled in a randomized phase II study of MK-0646 (M), a monoclonal antibody directed against the IGF-1 protein, in patients with metastatic pancreatic cancer (MPC). Two different doses of M were tested, 5 and 10 mg/kg. We used the Slice-o-matic (ver 4.3) software to segregate CT images into muscle and fat components and measured muscle area (cm(2)) at baseline and after 2 and 4 months of treatment. Patients received either gemcitabine with erlotinib (G + E), G + E + M, or G + M. Differences between the groups were compared using t tests., Results: Fifty-three patients had both baseline and 2-month imaging available for analysis. Of these, 42 received M with their chemo, and 11 had G + E only. After 2 months of treatment, both groups demonstrated decrease in muscle mass. G + E patients lost 5.6 % of muscle mass; M patients lost 9.1 and 8.6 % after treatment with 5 and 10 mg/kg, respectively (p = 0.53). Patients demonstrating a response lost less muscle (median 4.6 %) than those with stable disease (9.6 %) and progressive disease (8.9 %, p = 0.14). Muscle retention from baseline to 2-month imaging, defined as loss of <6 cm(2) of muscle, correlated with better survival than those patients demonstrating a muscle loss (HR 0.51, p = 0.03)., Conclusions: MPC patients can be expected to lose muscle mass even while having clinical benefit (PR or SD) from chemotherapy. Muscle loss correlated with a risk of study drop-out and death. There was a non-significant trend toward greater muscle mass loss in patients on anti-IGF-1R therapy. However, it is unclear if this loss translates into functional differences between patients.