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In the current study, a comparison between the different Mn3O4/ZnO, CuO/ZnO and Fe2O3/ZnO nanocomposites with respect to their structural, morphological, optical and photocatalytic properties is presented. The nanostructure nature of the investigated composites was confirmed by the XRD and SEM analysis. The nanocrystalline ZnO, M3O4, CuO and Fe2O3 phases were observed with different crystalline structure, including hexagonal, tetragonal, monoclinic and rhombohedral, respectively. The morphology of ZnO based nanocomposites was found to be dependent on the type of the metal oxide added to ZnO nanostructure. In addition, the studied nanocomposites showed different optical properties. The highest and lowest band gap of 3.14 and 2.00 eV were obtained for ZnO nanoparticles and Fe2O3/ZnO nanocomposite. Concerning the photocatalytic properties, the ZnO nanoparticles, Mn3O4/ZnO, CuO/ZnO and Fe2O3/ZnO nanocomposites showed an efficiency of 49.63, 29.8, 11.61 and 95.34%, respectively, for the photodegradation of methylene blue. The Fe2O3/ZnO nanocomposites exhibited the highest activity for water purification compared to the other nanocomposites. [ABSTRACT FROM AUTHOR]

We report the structural and nonlinear behavior of Sn1−x−yZnxMyOz varistors with x = 0.00, 0.50, y = 0.00, 0.25 and M = Fe, Co, Ni and Mn. The crystallite and grain sizes and porosity of SnO2 are decreased by Zn doping, followed by a further decrease by (Zn + M) co-substitution. The breakdown field (EB), nonlinear coefficient (α), leakage current (IK) and residual voltage (Kr) of SnO2 are respectively 333.35 V/cm, 5.6, 900 μA/cm2 and 5.32. When SnO2 was substituted by Zn, IK and Kr are decreased to 816 μA/cm2 and 3.62, whereas EB and α are increased to 666.67 and 11.48. The EB and α values are increased by co-substitution in the SnZnMn sample, whereas IK and Kr are decreased. Rather than containing many elements and compounds, the current varistors are based on only two well-known ions co-substituted into SnO2. These findings are discussed in terms of the oxygen vacancies. [ABSTRACT FROM AUTHOR]

We report here the structural, FTIR, optical, mechanical, and magnetic properties of Zn1−xFexO with various Fe nanopowder additions (0.00 ≤ x ≤ 0.30). The wurtzite structure and compressive stress are clearly conformed in all samples. Further, the lattice constants, crystallite size, porosity, strains, grain size, Debye temperature, and elastic modulus are increased as x increases to 0.05, followed by a decrease at x = 0.30, but they are higher than those of ZnO. Interestingly, two electronic transitions were observed for all samples corresponding to two values of energy gaps, Eg1 and Eg2. They were decreased from 3.25 and 3.72 eV to 3.00 and 3.60 eV, respectively. In contrast, an enhancement of the lattice constant ϵL, the density of charge carriers (N/m*), and the optical and electrical conductivities as x increases was obtained. For example, ϵL and charge carriers density (N/m*) for x = 0.30 doped sample are, respectively, 10 and 15 times more than those of ZnO. The refractive index (n) increases as x is increased, and a good correlation between n and Eg was obtained. Other parameters, such as the dissipation factor, surface and bulk loss functions, were also controlled by the variation of x. The non-linear optical parameters were also increased by increasing x, indicating not only the interesting optical properties of these materials but also the possibility of their optoelectronic applications. The Vickers hardness Hv is increased by increasing x to 0.30 and applying load to 9.8 N. In contrast, the surface energy γ, elastic indentation de, and resistance pressure decrease as x increases to 0.10, followed by an increase at x = 0.30. A noticeable ferromagnetic behavior with evaluated magnetization parameters is clearly obtained for the x = 0.10 sample. The saturation magnetization Ms is about 250 times greater than that of ZnO, which supports the room temperature ferromagnetic (RTFM) for the Fe-doped sample. These findings indicate that the addition of Fe as nanopowder to ZnO is promising for altering plastic flow region, optoelectronic, high-power operating and spintronic devices, which highlights the present investigation. [ABSTRACT FROM AUTHOR]

Background: Socioeconomic inequalities play an important role in health. Although studies report less inequalities in adolescent health compared to other age groups, there may be differences in their health behavior and mental health. Objective(s): This cross-sectional pilot study aimed to analyze these associations. Methods: Using a sample of students (n = 112, aged 13 - 18 years) data were collected from public and private schools in Irbid governorate, Jordan, November, 2018. Measurements included socioeconomic status indicators (education and income of the parents, assessed by the adolescent), the Global School-based Student Health Survey, health behaviors (tobacco use, personal hygiene, dietary behavior), Satisfaction with Life Scale, Center for Epidemiological Studies Depression Scale for Children. Results: The results indicated that there was a significant association between the family affluence and both paternal (p= 0.003) and maternal educational levels (p= 0.008). There was a relationship between paternal education and not having enough food at home (p= 0.006), adolescents' eating fruit per week (p= 0.037), and washing their hands before eating (p= 0.004). Maternal education level was related to the students' eating vegetables (p= 0.011) and fruits (p = 0.030) per week. The association of family affluence with eating fast food was significant (p= 0.05). The relationship of depression and family affluence was linear. Conclusion: Our findings suggest that adolescents' health behavior may dominantly be related to paternal education, while their mental health may be related to family affluence. The data of this study will help in establishing effective and efficient counseling and support intervention programs. [ABSTRACT FROM AUTHOR]

The next generation of electronic devices will require low cost materials and processing techniques that are fully compatible with flexible substrates and large area applications. Silver nanowires are promising candidates for many applications and can be processed by various solution-based large area deposition techniques. In this work, high aspect ratio silver nanowires were synthesized via a polyol reduction of silver nitrate in the presence of a metal-salt and a capping agent. The grown nanowires were spray coated and simply planarized with inkjet printed PEDOT:PSS to produce smooth and high performance nanocomposite electrodes suitable for industrial applications. The nanocomposite electrodes exhibit figure of merit values ( σDC/ σOP) of about 60, higher than the values required for industrial use (>35). High conductivity with high optical transparency was achieved by controlling the aspect ratio of the nanowires and their concentration in the films. The highly conductive and transparent electrodes were utilized to fabricate organic light emitting diodes, which exhibited high luminance (∼ 7 × 103 cd m−2) and performance comparable to a 'benchmark' ITO electrode. The results show that the combination of the nanocomposite materials, together with the solution based techniques could pave the way towards flexible, solution processable, low cost, and large area device applications. ITO-free OLEDs fabricated using solution processed Ag NW/PEDOT:PSS nanocomposites as transparent conductive electrode. Improving the aspect ratio of the grown nanowires along with controlling their density in the films allow for highly conductive and transparent nanocomposite electrodes. These nanocomposite samples are utilized as a direct replacement for ITO in OLEDs. [ABSTRACT FROM AUTHOR]

In this work, we report a theoretical investigation of the structural, electronic and optical properties of Cd 1 − x Ag x S alloys with a wurtzite structure. The calculations were performed using the density functional theory (DFT). The full potential linearized augmented plane wave (FPLAPW) scheme, implemented in Wien2k package, was employed. The modified Becke–Johnson potential with generalized gradient approximation (mBJGGA), which combines the Becke–Johnson exchange potential with the generalized gradient approximation correlation potential, was used to evaluate the alloys band structure. The study was carried out for the composition of silver x = 0 , 0.027, and 0.055. The obtained band structures and the density of states of these alloys revel that by increasing the silver composition in CdS matrix, the Fermi level cross the E(k) curves in the majority-spin states showing a metallic behavior. While the minority-spin state is semiconducting. A band gap channel was observed between the spin up and spin down level giving rise to a half metallic behavior. The origin of this bandgap is attributed to the silver d-band hybridization. The optical properties were also investigated and were found to be deeply affected by the silver composition. The optical absorption is gradually shifted to the lower energy and the compound becomes more absorbent in the infrared region. The structural and optoelectronic proprieties of the half metal Ag-doped CdS materials, were investigated and are presented in the current study and discussed in details. The findings of the study show that Cd 1 − x Ag x S alloys with their spin-based properties could pave the way for many novel optoelectronic devices in addition to spintronics applications. [Display omitted] • A decrease in the lattice parameters occurs after the substitution of Cd with Ag atoms in the CdAgS supercell. • The density of states shows a strong hybridization of the d states of Ag and the p orbitals of S near the Fermi level. • A transition from semi-metal to metal character of CdAgS occurs by increasing the silver composition. • The peaks of the dielectric function imaginary part in the lower energy region move to the infrared spectrum with the silver composition. • The Ag-doped CdS alloys clearly show novel electronic properties for optoelectronic applications. [ABSTRACT FROM AUTHOR]

In the current study, we investigated the partial decomposition of GaN layers grown on SiN-treated sapphire substrate in an atmospheric pressure metal organic vapor phase epitaxy (AP-MOVPE) vertical reactor under N 2 ambient at 1200 °C. Under these experimental conditions, we studied the decomposition of different coalescence degrees GaN layers and the early thermal decomposition stages of GaN films. By the help of the scanning electron microscope (SEM), the surface morphology of the decomposed GaN epilayers was examined. We demonstrated that the thermal decomposition leads to an irregular etching process, which was carried out step by step. The optical properties of the decomposed films were then studied by using the photoreflectance (PR) technique at room temperature and at 11 K. We determined a logarithmic relation between the built-in electric field in the surface of GaN layers and the stress value. A model is also proposed to extract the stress value from PR spectra. It should be noted also that by using the thermal decomposition process, the stress inside GaN layers can be reduced by a factor of 6. [ABSTRACT FROM AUTHOR]

Degenerative disc disease and low back pain are common challenges that persist even after a discectomy. However, characterizations and quantifications of these illnesses from the patients' perspective are insufficient. We aimed to perform a systematic review of the literature and meta-analysis to determine the frequency of chronic pain after spinal surgery. We searched MEDLINE (PubMed), Google Scholar, and the Saudi Digital Library to retrieve research articles describing the frequency of persistent back pain, reoccurring disc herniation, and undergoing another operation following primary lumbar discectomy. We excluded articles that did not disclose the proportion of patients who experienced ongoing back or leg pain for over six months after the operation. We included 16 studies evaluating 85,643 patients. The pooled prevalence of persistent pain was 14.97% (95% confidence interval: 12.38-17.76). With all advancements in technology and operation techniques, many patients (14.97%) still have failed back surgery syndrome. Appropriate preoperative communication and multidisciplinary and coordinated treatment strategies yielded the best results., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Alshammari et al.)

Background: School climate is one of several important factors influencing adolescent well-being and life satisfaction. Although a growing number of studies investigate the role of school climate, they often apply a global scale and only a few of them measure any specific elements. Likewise, most studies are focused on well-being and not life satisfaction., Aim: The purpose of this study is to investigate how different elements of school climate (teacher responsiveness, disruptive behavior, positive mutual bonds, classroom atmosphere, growth) are related to life satisfaction among a sample of Jordanian high school students., Methods: Using a self-administered and online questionnaire, the sample consists of adolescents from public schools located in northern Jordan (N = 2141, aged 13-18 years)., Results: Jordanian high school students' levels of life satisfaction were higher for girls [ t (2139) = -8.2, p < .001]. Disruptive behavior correlated negatively with classroom atmosphere ( r = -0.50; p < .001 among girls and r = -0.45; p < .001 for boys); teacher responsiveness was positively correlated with growth ( r = 0.49; p < .001 for girls and r = 0.61; p < .001 for boys). However, the role of disruptive behavior was different for girls (negative) compared to boys (positive), although these correlations were weak. In multiple regression analyses, teacher responsiveness ( β = 0.22; p < .001) and positive mutual bonds ( β = 0.19; p < .001) were largest contributors to life satisfaction beyond self-assessed socioeconomic status ( β = 0.27; p < .001). Age ( β = -0.08; p < .01) and growth ( β = 0.27; p < .001) were significant only for boys., Conclusions: These results demonstrate the importance of examining different elements of school climate in an effort to better understand adolescents' life satisfaction. Certain gender differences may highlight differences in social needs across different classroom settings which require further investigation., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)