Search

Purpose: Olfactory dysfunction is increasingly common among COVID-19 patients, impacting their well-being. Reports have demonstrated decreased levels of cyclic adenosine monophosphate and cyclic guanosine monophosphate among patients with chronic olfactory dysfunction. A prospective randomized clinical trial was developed to demonstrate the efficacy of an oral forskolin regimen treatment, an adenylyl cyclase activator that raises intracellular levels of cyclic adenosine monophosphate, for the treatment of olfactory dysfunction following COVID-19, compared to placebo regimen. Methods: The study enrolled 285 participants with persistent olfactory dysfunction post COVID-19 infection, randomly assigning them to receive either placebo capsules (n = 120) or oral forskolin capsules (n = 165). Follow-up was conducted to track progress, with 18 participants from the placebo group and 12 from the forskolin group lost during this period. Olfactory function was assessed using the "Sniffin' Sticks" test, measuring threshold, discrimination and identification scores before and after treatment. Results: Subjects administered forskolin capsules demonstrated a significant enhancement in their composite TDI (threshold, discrimination and identification) score, suggesting a notable amelioration in olfactory functionality. Moreover, the discrimination and identification scores notably improved within the forskolin group. Conversely, no significant alterations were observed in the threshold scores. Conclusion: This study suggests that forskolin can contribute potentially to improve chronic olfactory dysfunction post COVID-19. Trial registration: DFM-IRB00012367-23-10-001. [ABSTRACT FROM AUTHOR]

Background: Effective medication management, disposal, and donation are vital for public health and environmental sustainability. Improper handling of medications can lead to drug misuse, accidental poisoning, and environmental damage. This study examines current practices and challenges in Saudi Arabia, identifying opportunities for improvement. Method: A cross-sectional survey conducted in October and November 2023 targeted the general population in Saudi Arabia. This study employed convenience sampling to explore medication usage, storage, disposal practices, and awareness of donation procedures. Data were analyzed through both descriptive and inferential statistical methods. Results: This study involved 430 respondents. Of these, 73.0% held a university degree, yet 66.3% were unaware of drug donation programs, and 84.2% lacked knowledge about proper medication disposal. Despite this, 71.4% believed that drug donation programs positively impact healthcare, and 87.9% saw them as reducing drug waste and environmental pollution. However, 48.1% expressed concerns about the potential misuse of donated medicines. Awareness and knowledge were significantly higher among participants aged 30 and above. Conclusions: The findings highlight the need for enhanced public awareness, clear medication disposal guidelines, and ethically governed donation practices in Saudi Arabia. These measures can improve healthcare outcomes, protect the environment, and support global health and sustainability goals. [ABSTRACT FROM AUTHOR]

Introduction: Professional certification programs play a crucial role in helping pharmacists develop specialized skills and establish their expertise in the field. This study explores how pharmacists in Saudi Arabia engage with these programs by examining their levels of awareness, attitudes, and participation. It also identifies the key barriers and motivators that influence their decision to pursue certification. Methods: An online survey was conducted among pharmacists in Saudi Arabia to assess participants' knowledge of certification programs, their perceived benefits, the actual participation rates, and their preferences regarding certification areas and assessment methods. Results: Out of 394 participating pharmacists, around 47% had never participated in a professional certification program, and about 27% of our sample were unaware of such programs in Saudi Arabia. Financial constraints and a lack of awareness were noted as the primary barriers to participation. Almost 55% showed an interest in Clinical Pharmacy Specialties certification, while 54% were inclined toward Pharmacy Management and Leadership certifications. A preference for practical assessments in certification programs was suggested by 55% of participants. Conclusions: This study highlights a significant need for increased awareness and accessibility to professional certification programs among pharmacists in Saudi Arabia. Addressing participation barriers is vital to foster professional development and meet the healthcare sector's evolving demands in Saudi Arabia. [ABSTRACT FROM AUTHOR]

ZnO nanostructured materials have been widely utilized in several environmental depollution applications. In the current work, ZnO nanorods were grown using the electrodeposition method with different precursor concentrations. A variation in the dimensions of the nanorods grown with the different precursor concentrations was noticed, as expected. The ability of the fabricated nanorods to remove water pollutants under UV irradiation and their photocatalytic performance stability was also evaluated over a prolonged period of time. Interestingly, the samples grown in different conditions exhibited different capabilities to maintain their morphology and their photocatalytic performance after they were kept in contaminated water for a long time. Moreover, some samples also were found to remain photocatalytically active for approximately 47% longer than other samples. These findings indicate that the performance stability of ZnO nanorods for pollutants removal and their robustness can be greatly improved by controlling their growth parameters, which will favorably impact the use of ZnO nanorods for water-treatment applications and their economic aspects. [ABSTRACT FROM AUTHOR]

Nanocomposite materials have demonstrated excellent performance in many application fields. Metal nanoparticle/graphene oxide composites are among the most promising composite materials for catalytic applications. In this study, nanocomposites of Au-Pd bimetallic particles/graphene oxide were prepared from an aqueous bath and used as catalysts in the oxidation reactions of some chemical compounds. The oxidation and exfoliation of graphite were controlled by varying the acid treatment time. The effects of the treatment time on the properties and performance of the prepared bimetallic-nanoparticle-supported graphene oxide catalysts were very obvious. Depending on the treatment time, a significant improvement in the conversion efficiency ranging from 65% to about 480%, along with a high oxidation selectivity, were achieved. The obtained findings show that the catalytic performance of metal/graphene oxide nanocomposites can be easily maximized by controlling the oxidation and exfoliation of graphene sheets. [ABSTRACT FROM AUTHOR]

Graphene derivatives have demonstrated high potential for various applications, including environmental ones. In this work, graphene oxide nano-sheets were obtained by utilizing a simple chemical method and were tested for water treatment applications. The pollutant adsorption ability of the produced GO was adjusted through a proper oxidation treatment of the graphene nano-sheets. The GO treatment time was systematically varied to control the oxidation level of the graphene nano-sheets and was found to considerably affect the GO's properties and performance in removing methylene blue. The microscopic studies showed well-exfoliated, few-layer GO nano-sheets. EDS and FTIR techniques were used to probe the presence of oxygen functional groups on the GO surface. The XRD investigations revealed various crystallinity levels of the prepared GO nano-sheets depending on the treatment time. The MB degradation efficiency was maximized by optimizing the GO treatment time. The results showed that the oxidation treatment parameters of GO play a major role in adjusting its properties and can be effectively utilized to boost its performance for water purification applications. [ABSTRACT FROM AUTHOR]

In this study, we assess healthcare providers' adherence to therapeutic drug monitoring (TDM) guidelines for gentamicin in neonates. Conducted at the Maternity and Children's Hospital in Makkah, Saudi Arabia, from July 2020 to July 2022, it retrospectively analyzed the compliance of healthcare workers in managing neonates treated with gentamicin. Covering 410 neonates, primarily diagnosed with respiratory distress (56%) and sepsis (32%), the study revealed that while a majority of trough and peak levels conformed to guidelines, substantial deviations were noted in cases of respiratory distress. This underlines the necessity for targeted TDM strategies, particularly in managing respiratory distress in neonates, to ensure optimal treatment efficacy and safety. The findings urge stringent compliance with TDM guidelines, emphasizing personalized approaches in neonatal gentamicin therapy for improved healthcare outcomes. [ABSTRACT FROM AUTHOR]

Background: Coagulation disorders are frequently encountered among patients infected with coronavirus disease 2019 (COVID-19), especially among admitted patients with more severe symptoms. This study aims to determine the mortality rate and incidence and risk factors for venous thromboembolism (VTE) in hospitalized patients with COVID-19. Methods: This retrospective observational cohort study was conducted from March to July 2020 using a hospital database. All adult patients (>18 years old) with laboratory-confirmed COVID-19 were included. Laboratory data and the real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) for SARS-CoV-2 were obtained from medical records. The mortality rate and the incidence of VTE were established as study results. A multivariate logistic regression analysis was performed to identify predictors of thrombotic events. Results: rA total of 1024 confirmed COVID-19 patients were treated, of whom 110 (10.7%) were deceased and 58 patients (5.7%) developed VTE. Death occurred more frequently in patients older than 50 years and those admitted to the intensive care unit (ICU, 95%) and who received mechanical ventilation (62.7%). Multivariate analysis revealed that cancer patients were two times more likely to have VTE (adjusted odds ratio = 2.614; 95% CI = (1.048–6.519); p = 0.039). Other chronic diseases, such as diabetes, hypertension, and chronic kidney disease, were not associated with an increased risk of VTE. Conclusions: One-tenth of hospitalized COVID-19 patients were deceased, and VTE was prevalent among patients with chronic conditions, such as cancer, despite anticoagulation therapy. Healthcare professionals should closely monitor individuals with a high risk of developing VTE to prevent unwanted complications. [ABSTRACT FROM AUTHOR]

Copyright of Saudi Medical Journal is the property of Saudi Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

The main goal of the present paper is to fabricate ZnO nanorods (NRs) as well as to investigate their structural, optical and photocatalysis properties. The proposed study could help in the development of these materials to be used in optoelectronic and water treatment applications. The ZnO NRs were synthesized on gold (Au)-coated glass substrates by electrochemical deposition technique. The SEM images demonstrated the uniform and dense development of ZnO NRs. The NRs' average diameter and length increased from 87 to 368 and from 357 to1600 nm, respectively, by increasing the growth time from 30 to 180 min. The ZnO NRs have hexagonal crystalline structure and grow in the direction of the (200) plane. The optical absorption analysis showed a decrement of the band gap of ZnO NRs from 3.17 to 2.69 eV by the variation of time from 60 to 180 min. The refractive index, dissipative factor and electron loss functions were affected also by the deposition time. The photocatalytic activity of ZnO NRs was improved by an increase in both irradiation and deposition time. [ABSTRACT FROM AUTHOR]

Gold nanoparticles have gained popularity as an effective drug delivery vehicle due to their unique features. In fact, antibiotics transported via gold nanoparticles have significantly enhanced their potency in the recent past. The present study used an approach to synthesize gold nanoparticles in one step with the help of cefoxitin antibiotic as a reducing and stabilizing agent. Cefoxitin is a second-generation cephalosporin that loses its potential due to modification in the porins (ompK35 and ompK36) of Gram-negative pathogens. Thus, the present study has developed an idea to revive the potential of cefoxitin against clinical Gram-negative pathogens, i.e., Escherichia coli and Klebsiella pneumoniae, via applying gold nanoparticles as a delivery tool. Prior to antibacterial activity, characterization of cefoxitin–gold nanoparticles was performed via UV–visible spectrophotometry, dynamic light scattering, and electron microscopy. A characteristic UV–visible scan peak for gold nanoparticles was observed at 518 nm, ζ potential was estimated as −23.6 ± 1.6, and TEM estimated the size in the range of 2–12 nm. Moreover, cefoxitin loading efficiency on gold nanoparticles was calculated to be 71.92%. The antibacterial assay revealed that cefoxitin, after loading onto the gold nanoparticles, become potent against cefoxitin-resistant E. coli and K. pneumoniae, and their MIC50 values were estimated as 1.5 μg/mL and 2.5 μg/mL, respectively. Here, gold nanoparticles effectively deliver cefoxitin to the resistant pathogens, and convert it from unresponsive to a potent antibiotic. However, to obtain some convincing conclusions on the human relevance, their fate and toxicity need to be evaluated. [ABSTRACT FROM AUTHOR]

Social differences are evident in both developed and developing countries. During adolescence, there are limited differences in morbidity and mortality, but differences do appear in terms of health behaviours. This study aims to examine the relationship(s) between social differences and students' health behaviours. A cross-sectional study was conducted in 2020 with a sample of high school students (N = 2741, aged 13–18 years) in Jordan. Besides descriptive statistics, bivariate logistic regression analysis was used to detect the odds risk for each social difference indicator. Females were engaged in more healthy dietary and hygienic behaviours and less engaged in smoking. Males were more physically active. Adolescents with a higher parental education level were more engaged in healthy behaviours; however, they drank carbonated soft drinks and ate fast food more often. Higher SES (socioeconomic status) self-evaluation was positively associated with eating breakfast and fruit and vegetables, being physically active, drinking carbonated soft drinks, eating fast food, and smoking. Our findings suggest that socioeconomic differences are important to understanding Jordanian adolescents' health behaviours. While females tend to engage in more healthy behaviours, the role of parental education and perceived family affluence is not always beneficial in terms of adolescents' dietary habits, hygienic behaviour, or smoking. [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]

Social support from family, friends, and others enhances the quality of life and acts as an important protective mechanism against mental health problems. The purpose of this study is to investigate how social support is related to mental health outcomes among Jordanian adolescents. Data were collected in 2020 from public and private schools in Irbid governorate, Jordan. Multistage cluster sampling was used to recruit students from 8th – 12th grades (N = 2741; ages 13–18 years). The study finds social support is related to higher levels of life satisfaction and self-esteem. The negative association between social support and depressive symptoms is also significant. Our findings underscore the importance of the role of social support, especially support from family. This support is important to adolescents' mental health and underscores the importance of policymakers giving greater attention to the family dynamic and its impact on student well-being. [ABSTRACT FROM AUTHOR]

The Arabian Shield of Saudi Arabia represents part of the Arabian–Nubian Shield and forms an exposure of juvenile continental crust on the eastern side of the Red Sea rift. Gabbroic intrusions in Saudi Arabia constitute a significant part of the mafic magmatism in the Neoproterozoic Arabian Shield. This study records the first detailed geological, mineralogical and geochemical data for gabbroic intrusions located in the Gabal Samra and Gabal Abd areas of the Hail region in the Arabian Shield of Saudi Arabia. Geological field relations and investigations, supported by mineralogical and geochemical data, indicate that the gabbroic intrusions are generally unmetamorphosed and undeformed, and argue for their post-collisional emplacement. Their mineralogical and geochemical features reveal crystallization from hydrous, mainly tholeiitic, mafic magmas with arc-like signatures, which were probably inherited from the previous subduction event in the Arabian–Nubian Shield. The gabbroic rocks exhibit sub-chondritic Nb/U, Nb/Ta and Zr/Hf ratios, revealing depletion of their mantle source. Moreover, the high ratios of (Gd/Yb)N and (Dy/Yb)N indicate that their parental mafic melts were derived from a garnet-peridotite source with a garnet signature in the mantle residue. This implication suggests that the melting region was at a depth exceeding ∼70–80 km at the garnet stability field. They have geochemical characteristics similar to other post-collisional gabbros of the Arabian–Nubian Shield. Their origin could be explained by adiabatic decompression melting of depleted asthenosphere that interacted during ascent with metasomatized lithospheric mantle in an extensional regime, likely related to the activity of the Najd Fault System, at the end of the Pan-African Orogeny. [ABSTRACT FROM AUTHOR]

This work reports the fabrication of Er@CdS films with 0, 1, 3, 5 wt% Er contents incorporated in CdS via spray pyrolysis route. The films were developed successfully with hexagonal structure and preferred growth orientation along (002) plane and crystallites sizes were found in the range 8–13 nm. Raman spectra showed the 1LO and 2LO vibrational bands centered at 300 cm−1 and 600 cm−1; respectively which confirms the synthesis of pure CdS. The optical band gaps of the films were found in range of 2.38–2.41 eV. A clear reduction in the band gap values is observed as with the incorporation of Er in the CdS matrix. In addition, Er@CdS thin films were utilized to construct a high performance photodetector (PD). The fabricated device shows enhanced visible light photodetection in comparison with the pure CdS films based device. The rise and decay time were detected in the range of 0.079–0.32 s and 0.099–0.32 s, respectively. Noticeable enhancements in responsivity (R) and the external quantum efficiency (EQE) were recorded, reaching maximum values as high as 4.95 A/W and 1150% for 3 wt% Er-doped films. This improvement in the PD performance may be due to the reduction in the defects and sulfur vacancies as a result of Er incorporation in the CdS matrix. [ABSTRACT FROM AUTHOR]

This paper presents experimental and density functional theory (DFT) investigations of Zn doping role in the Zn@CdO ternary system. Zn doped CdO nanostructures thin films with different Zn concentrations were successfully casted on glass substrates by sol–gel spin coating method. Cubic Zn@CdO structured ternary alloyed nanostructures thin films with 0.0, 1.0, 2.0 and 3.0 wt.% Zn concentrations were obtained. An enhancement in the lateral growth of CdO cauliflower-like nanostructures was observed after Zn addition which leads to a growth of nanostructured films with improved continuity. The effect of Zn doping on the linear optical parameters such as the optical band gap, the absorption index and the refractive index were also investigated. A remarkable blue shift in the band edge was observed as Zn is incorporated into the CdO matrix. In addition, the third order nonlinear optical parameters χ(3) and n2 were calculated and found to be about 2.89 × 10–12–4.33 × 10–14 esu and 2.89 × 10–12–4.33 × 10–14 esu; respectively. A DFT based Wien2k package was utilized to theoretically investigate the lattice parameters, the electronic structure, the absorption index and the refractive index of the Zn@CdO ternary nanoalloys. The role of Zn doping on the aforesaid properties was theoretically investigated for 3.125%, 6.25%, 12.5% and 25% Zn doping concentrations and was compared with the experimentally determined parameters. The combined theoretical and experimental investigations presented herein along with the detailed discussion of the obtained findings would provide a deep understanding of the opto-electronic behavior of the Zn doped CdO nanostructured films as well as their suitability for devices applications. [ABSTRACT FROM AUTHOR]

The current work presents the optical, photoluminescence and ferromagnetic properties of Zn1−xNixO samples with (0.00 ≤ x ≤ 0.20). The samples are well crystallizing in hexagonal wurtzite structure without a significant change in their lattice constants, while the crystallite size, grain size and number of unit cells in ZnO particle are increased. The residual stress is negative (compressive) and almost increases as Ni increases up to 0.10, but it is changed from negative to positive (tensile) at Ni = 0.20. The absorption and reflectance of UV spectra are increased as Ni increases up to 0.20. An absorption band centered at a wavelength of 552 nm is also observed and is gradually shifted by Ni towards longer wavelengths. Interestingly, two direct electronic transitions are found for all samples and two induced bandgaps which are decreased by Ni. While the other optical constants such as linear χ1 and non-linear third-order susceptibilities χ3, dispersion parameters (Ed, Eo), refractive indexes (no, n2), lattice dielectric constant εL, N/m*, optical and electrical conductivities (σopt, σele) are increased by Ni, the dissipation factor (tanδ) is decreased. Although some of the continuous peaks of lower PL intensities are recorded at UV band edges and slightly shifted to longer wave lengths (red shift) as Ni increases, strong UV emission peaks at about 390, 420 and 440 nm are recorded. Finally, the signature of a clear weak ferromagnetism ordering at room temperature, with evaluated magnetic parameters such as magnetization Ms, magnetic moments μ and magneto-crystalline anisotropy factor γ, is recorded for Ni ≥ 0.05 doped samples. [ABSTRACT FROM AUTHOR]

Cd–ZnO–Na alloy nanostructured thin films were synthesized via sol–gel spin coating method on glass substrates and the effect of Na (1, 2 and 3 wt%) doping variation on linear, nonlinear optical, opto-dielectric, and emission properties of the films was investigated. The variations in physical properties with different Na doping concentrations were analyzed using X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscope (SEM), FT-Raman, UV–Vis, and photoluminescence spectroscopy. From XRD patterns, it was observed that the growth of the films occurs along (002) plane with hexagonal wurtzite structure. High percentage of transmittance (viz. 85 to 90%) was recorded for all as grown films. However, the estimated bandgap energy of the films was found to decrease from 3.37 to 3.30 eV with increasing Na doping concentration from 1 to 3 wt%. Emission spectra of the films show an intense and sharp peak near band emission (NBE) at 389 nm whereas a low intense peak was observed at 475 nm. The intensity of NBE peak specifies the significant enhancement in photoluminescence properties of the grown films with increasing Na doping concentrations. Nonlinear optical parameters of the Cd–ZnO–Na films such as χ3 and n2 showed substantial improvements, which were deduced and obtained in the range 1.11 × 10–14–1.91 × 10–12 esu and 5.20 × 10–13–3.19 × 10–11 esu, respectively. The achieved improvement in the grown ZnO films via co-doping with Cd and Na makes them highly suitable candidates for optoelectronics devices applications. [ABSTRACT FROM AUTHOR]

Cadmium sulphide (CdS) thin films are widely used for various devices applications. Here, we report on the development of nanostructured CdS and Na-CdS thin films with enhanced optical and emission properties using an inexpensive deposition method. High quality Na-CdS nanocrystalline films were fabricated using spin coating method on glass substrates with different doping concentration (1–4 wt%). X-ray diffraction studies of the prepared films reveal a cubic zinc blende structure. The crystallites sizes of the films were found to be about ~ 5–11 nm and significantly increase with increasing Na doping concentrations. Morphological imaging of the grown films shows spherical nano-size grains in the range of 9–27 nm. The nanocrystalline films show high transmittance (~ 85%) in the visible region and was found to increase with increasing Na doping content. Room temperature photoluminescence (RTPL) spectra of the films reveal a direct band to band transition with enormous amount of enhancement in near band emission (NBE) up to 400% for the films doped with 1 and 2 wt% Na concentrations which is about ten times higher as compared with pure CdS films. A good improvement was also observed with Na doping in the linear and third order nonlinear optical properties of the films. The reported results in the current study show the high potential of Na-doped CdS films as candidates for low cost high performance optoelectronic devices. [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]

Pure and Ag doped CdS nanocrystalline films with different Ag doping concentrations were successfully grown on glass substrates by a sol-gel spin coating method. Ag doping was performed using silver acetate aqueous solution with 0.01, 0.02 and 0.03 M concentrations via ion exchange. The influences of Ag doping on structural, vibrational, morphological, linear and third order nonlinear optical properties of CdS nanocrystalline films were studied. The x-ray diffraction patterns of the films exhibited a broad peak centered at an angle 2θ = 26.5° along the (111) plane, which confirms the cubic structure and formation of nanocrystalline films. Raman spectra of films demonstrate a shift in longitudinal optical phonon vibrations as compared to the bulk counterpart. Pure CdS film shows high transmittance (83%) in the visible and near infrared (NIR) regions. With Ag doping, a significant red shift in the band edge and reduction in the transmittance of the films in visible and NIR regions were observed. However, the films doped with Ag showed appreciable transmittance in visible region for window layer applications. A significant effect on optical parameters such as absorption index, refractive index, and optical dielectric constant was observed after Ag doping. The nonlinear optical properties of films were enhanced with incorporation of Ag atoms into the CdS binary system. The values of nonlinear optical susceptibility χ(3) and refractive index n2 were found to increase with increasing Ag concentration and were estimated to be in the range of 2.92 × 10−10 − 1×10−7esu and 1.00 × 10−9 − 2.00 × 10−7esu, respectively. These values suggest that these films can be potential candidates for nonlinear optical device applications. [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]

The size and density of nanopits, generated at the surface of their top layer, strongly affect the electrical and optical properties of AlGaN-based structures. Therefore, the control of the layer quality evolution as a function of the nanopits size/density is a crucial issue to enhance the device performance. In this paper, the effects of the nanopits diameter observed at the surface of AlGaN on carrier dynamics are systematically investigated. The variation of nanopits diam-eter is achieved through thermal annealing of a set of AlGaN/GaN heterostructures at different temperatures. The samples are characterized using the scanning electron microscope (SEM), energy-dispersive x-ray, high-resolution x-ray diffraction, photoluminescence (PL), and time-resolved PL spectroscopies. SEM images have revealed an increase in the nanopits diameter with increasing annealing temperature. In addition, we observed a linear development in the yellow luminescence intensity, accompanied by a deterioration in the PL decay times due to an increase in the density of point-defect complexes that act as nonradiative recombination centers. We also performed temperature-dependent PL measurements to study the impact of the nanopits diameter on electron–phonon scattering processes. Both electron-acoustic- and electron-longitudinal optical phonon interactions enhance with increasing nanopits diameter. [ABSTRACT FROM AUTHOR]

The long-term stability of multiwall carbon nanotubes (MWCNTs) mixed with the hole-transport polymer Poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) has been examined. These surfactant stabilized solutions, used as transport layers in organic light-emitting diodes (OLEDs), are shown to be stable for periods of up to 15 months and show no signs of degrading soon after this time. In comparison, nonstabilized aqueous MWCNT solutions have been shown to aggregate within 30 min of production, and, although these aggregates can be redispersed, the solution displays an increase in smaller aggregates over time which cannot subsequently be redispersed by manual agitation. The stable MWCNT/PEDOT:PSS solutions have been used in ink-jet printing and as composite MWCNT/PEDOT:PSS films suitable as charge transport layers in spin-coated OLEDs. [ABSTRACT FROM PUBLISHER]

The improvement of the surface properties of ferrous metallic materials has become a crucial criterion for advanced engineering applications. The interfacial microstructure and corrosion behaviour of mild steel coated with alumina nanoparticles doped in tin composite using the direct tinning technique were investigated. A coating layer of tin composite containing different loads of Al2O3 nanoparticles (0.25 wt.%, 0.50 wt.%, 1.00 wt.% and 1.5 wt.%) was prepared and directly deposited on a mild steel substrate. This type of a direct tinning process is considered to be a simple and low-cost route for protecting metallic materials from corrosion. It was found that the thickness of both the composite layer and Fe-Sn intermetallic layer at the coated interfaces was highly affected by the presence of alumina nanoparticles that effectively inhibit the diffusion of Sn atoms into the Fe substrate. For the samples coated with lower content of alumina nanoparticles (0.25 wt.% and 0.50 wt.%), the thickness of the Fe-Sn intermetallic coating (IMC) layer is decreased due to Fe-Sn IMC suppression. Otherwise, for the addition of more alumina nanoparticles (1.00 wt.% and 1.50 wt.%), the thickness of the Fe-Sn IMC layer is slightly increased because of nanoparticle's agglomeration and flotation. It can be reported that the presence of alumina nanoparticles in the coating layer improves, to a great extent, the corrosion resistance of Sn-composites surface on mild steel substrates. Although the tin composite coating layer with a high quantity of alumina nanoparticles (1.0 wt.%) exhibited better corrosion resistance than the other tested samples, such nanoparticle additions have become increasingly difficult to obtain. It was observed that the Al2O3 nanoparticles agglomeration and flotation that were detected in the coating surface may be related to high fraction nanoparticles loading and to the difference in the gravity for Sn and Al2O3 nanoparticles. However, based on our investigation, a coating layer that contains 0.50 wt.% alumina nanoparticles is highly recommended for achieving long lasting and high-performance corrosion resistance for coated mild steel with minimal coating layer defects. [ABSTRACT FROM AUTHOR]

The proper assessment of trace element concentrations in the north Nile Delta of Egypt is needed in order to reduce the high levels of toxic elements in contaminated soils. The objectives of this study were to assess the risks of contamination for four trace elements (nickel (Ni), cobalt (Co), chromium (Cr), and boron (B)) in three different layers of the soil using the geoaccumulation index (I-geo) and pollution load index (PLI) supported by GIS, as well as to evaluate the performance of partial least-square regression (PLSR) and multiple linear regression (MLR) in estimating the PLI based on data for the four trace elements in the three different soil layers. The results show a widespread contamination of I-geo Ni, Co, Cr, and B in the three different layers of the soil. The I-geo values varied from 0 to 4.74 for Ni, 0 to 6.56 for Co, 0 to 4.11 for Cr, and 0 to 4.57 for B. According to I-geo classification, the status of Ni, Cr, and B ranged from uncontaminated/moderately contaminated to strongly/extremely contaminated. Co ranged from uncontaminated/moderately contaminated to extremely contaminated. There were no significant differences in the values of I-geo for Ni, Co, Cr, and B in the three different layers of the soil. According to the PLI classification, the majority of the samples were very highly polluted. For example, 4.76% and 95.24% of the samples were unpolluted and very highly polluted, respectively, in the surface layer of the soil profiles. Additionally, 14.29% and 85.71% of the samples were unpolluted and very highly polluted, respectively, in the subsurface layer of the soil profiles. Both calibration (Cal.) and validation (Val.) models of the PLSR and MLR showed the highest performance in predicting the PLI based on data for the four studied trace elements, as an alternative method. The validation (Val.) models performed the best in predicting the PLI, with R2 = 0.89–0.93 in the surface layer, 0.91–0.96 in the subsurface layer, 0.89–0.94 in the lowest layers, and 0.92–0.94 across the three different layers. In conclusion, the integration of the I-geo, PLI, GIS technique, and multivariate models is a valuable and applicable approach for the assessment of the risk of contamination for trace elements, and the PLSR and MLR models could be used through applying chemometric techniques to evaluate the PLI in different layers of the soil. [ABSTRACT FROM AUTHOR]

The present study focuses on the risk assessment of heavy metal contamination in aquatic ecosystems by evaluating the current situation of heavy metals in seven locations (North Amer El Bahry, Amer, Bakr, Ras Gharib, July Water Floud, Ras Shokeir, and El Marageen) along the Suez Gulf coast that are well-known representative sites for petroleum activities in Egypt. One hundred and forty-six samples of surface sediments were carefully collected from twenty-seven profiles in the intertidal and surf zone. The hydrochemical parameters, such as pH and salinity (S‰), were measured during sample collection. The mineralogy study was carried out by an X-ray diffractometer (XRD), and the concentrations of Al, Mn, Fe, Cr, Cu, Co, Zn, Cd, and Pb were determined using inductively coupled plasma mass spectra (ICP-MS). The ecological risks of heavy metals were assessed by applying the contamination factor (CF), enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLI), and potential ecological risk index (RI). The mineralogical composition mainly comprised quartz, dolomites, calcite, and feldspars. The average concentrations of the detected heavy metals, in descending order, were Al > Fe > Mn > Cr > Pb > Cu > Zn > Ni > Co > Cd. A non-significant or negative relationship between the heavy metal concentration in the samples and their textural grain size characteristics was observed. The coastal surface sediment samples of the Suez Gulf contained lower concentrations of heavy metals than those published for other regions in the world with petroleum activities, except for Al, Mn, and Cr. The results for the CF, EF, and Igeo showed that Cd and Pb have severe enrichment in surface sediment and are derived from anthropogenic sources, while Al, Mn, Fe, Cr, Co, Ni, Cu, and Zn originate from natural sources. By comparison, the PLI and RI results indicate that the North Amer El Bahry and July Water Floud are considered polluted areas due to their petroleum activities. The continuous monitoring and assessment of pollutants in the Suez Gulf will aid in the protection of the environment and the sustainability of resources. [ABSTRACT FROM AUTHOR]

Although supported bimetallic nanoparticles (Au-Pd NPs) demonstrate outstanding efficiency, challenges appear for carbon supported small and stable bimetallic nanoparticles used in liquid-phase reactions. In this work, Au-Pd NPs were supported on two types of carbon nanotubes: CNTs decorated covalently with carboxylic acid groups (O-CNTs) and non-covalently with the conductive poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) polymer (P-CNTs). The Au-Pd NPs were prepared using the sol immobilization approach on the functionalized CNTs, and the effect of the utilized functionalization method on the properties of the immobilized metallic nanoparticles and the performance of the nanocomposite catalysts was investigated. The fabricated nanocomposites were characterized using Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, High-resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM). The catalytic performance of Au-Pd/O-CNTs and Au-Pd/P-CNTs was exploited for the oxidation of both cyclooctene and benzyl alcohol. Oxidation and polymer decoration directly led to an enhancement in the performance of CNTs catalysts. The nanocomposite catalyst with oxidized CNTs (Au-Pd/O-CNTs) was also found to be much more efficient and robust than that with polymer decorated CNTs (Au-Pd/P-CNTs). The enhancement in the oxidation of both cyclooctene and benzyl alcohol on Au-Pd/O-CNTs is attributed to the well-dispersed and smaller Au-Pd NPs as active sites on the surface of O-CNTs as compared to the P-CNTs surface. [ABSTRACT FROM AUTHOR]

Assessing surface water quality for drinking use in developing countries is important since water quality is a fundamental aspect of surface water management. This study aims to improve surface water quality assessments and their controlling mechanisms using the drinking water quality index (DWQI) and four pollution indices (PIs), which are supported by multivariate statistical analyses, such as principal component analysis, partial least squares regression (PLSR), and stepwise multiple linear regression (SMLR). Twenty-two physicochemical parameters were analyzed using standard analytical methods for 55 surface water sites in the northern Nile Delta, Egypt. The DWQI results indicated that 33% of the tested samples represented good water, and 67% of samples indicated poor to unsuitable water for drinking use. The PI results revealed that surface water samples were strongly affected by Pb and Mn and were slightly affected by Fe and Cr. The SMLR models of the DWQI and PIs, which were based on all major ions and heavy metals, provided the best estimations with R2 = 1 for the DWQI and PIs. In conclusion, integration between the DWQI and PIs is a valuable and applicable approach for the assessment of surface water quality, and the PLSR and SMLR models can be used through applications of chemometric techniques to evaluate the DWQI and PIs. [ABSTRACT FROM AUTHOR]

We report the investigation of structure, morphology, photocatalytic degradation of methyl blue using ZnO nanorods (NRs). The ZnO NRs samples were fabricated using electrochemical deposition from aqueous solution of zinc nitrate and hexamethylenetetramine on ITO substrates. The effect of the growth time on the structure, morphology and photocatalytic properties of ZnO NRs was investigated in details.XRD analysis showed that the fabricated NRs have hexagonal wurtzite structure and growth direction along the (002) plane. The morphology of the prepared samples investigated by SEM showed that growth rate of the NRs depends on the time of the growth. The surface area and cross-sectional area of the fabricated ZnO NRs increased with increasing the growth time and led to improvements in the NRs aspect ratios. It was also found that the photocatalytic activity of the grown nanorods enhances by increasing the deposition time. The present results are discussed in terms of the observed structural morphology of the investigated ZnO NRs and correlated with the photocatalytic performance of the grown NRs. [ABSTRACT FROM AUTHOR]