Fabrication of rGO-bridged TiO2/g-C3N4 Z-scheme Nanocomposites via Pulsed Laser Ablation for Efficient Photocatalytic CO2 Reduction.

Highly efficient photocatalysts can be fabricated using favorable charge transfer nanocomposite channel structures. This study adopted pulsed laser ablation in liquid (PLAL) to obtain rGO-bridged TiO2/g-C3N4 (rGO-TiO2/g-C3N4) photocatalytic Z-scheme without the need for noble metals. In addition to evaluating the resulting nanocomposite's (comprising rGO nanosheets, TiO2 nanotubes, and g-C3N4 nanosheets) CO2 reduction effectiveness, its chemical, morphological, structural, and optical characteristics were examined using various analytical techniques. The findings revealed a synergistic interaction between g-C3N4 and TiO2, suggesting the presence of unique interfacial bonding, as well as enhanced visible light absorption. Notably, the ternary rGO-TiO2/g-C3N4 Z-scheme exhibits an excellent photocatalytic performance by photocatalytically converting CO2 into CO and CH4, with 81% selectivity towards the CO and 1.91% apparent quantum efficiency at 420 nm. Thus, the findings can pave the way for various Z-scheme systems in wide photocatalytic applications.

Prevalence of Gastroesophageal Reflux Disease and Its Impact on the Quality of Life Among Obese Individuals in Al-Baha Region, Saudi Arabia.

Background Gastroesophageal reflux disease (GERD) is a global gastrointestinal disorder, and obesity is a particular risk factor. Symptoms of GERD, such as heartburn and acid reflux, are caused by abnormal relaxation in the lower esophagus, causing gastric acid reflux. Persistent symptoms can affect the patient's quality of life (QOL) and can cause complications, such as esophageal adenocarcinoma. Management of GERD includes lifestyle changes, antacids, and anti-reflux surgery. Even though GERD is a common disease, few research has been carried out on it in Saudi Arabia. Aim This study aimed to estimate the prevalence of GERD and its associated risk factors among obese individuals in the Al-Baha region population and the effect of GERD on their QOL. Methods A cross-sectional study included 314 obese participants from the Al-Baha region. A questionnaire was filled out to measure the prevalence of GERD, risk factors, and effects on the QOL of the participants. Data were analyzed by the IBM SPSS Statistics for Windows, version 26.0 (released 2019, IBM Corp., Armonk, NY). Descriptive statistics and the chi-squared test were applied. Logistic regression analysis was used to determine the factors associated with the incidence of GERD. A p-value of <0.05 was considered statistically significant. Results A total of 314 patients who met our inclusion criteria completed the survey; 42% of them were women, the mean age of all patients was 35.3 ± 12.9 years, and 38.2% of the patients were diagnosed with GERD. Epigastric pain and burning sensation were the most common symptoms (44.9%). Five out of six domains in the QOL questionnaire showed more effects among GERD participants than non-GERD participants, and the results were statistically significant (p = 0.001). Logistic regression analysis showed that men are 1.8 times more likely than women to be diagnosed with GERD, and smokers have 2.6 times the risk of being diagnosed with GERD than non-smokers. Conclusion The present study showed a high prevalence of GERD among obese patients in the Al-Baha region, negatively affecting their QOL. Major risk factors included gender, smoking, dyslipidemia, and hypertension. Public health programs to raise awareness of these risk factors and lifestyle habits are necessary to improve QOL and prevent complications.

The development of a grey relational analysis-based composite index for environmental sustainability assessment: Towards a net-zero emissions strategy in Saudi Arabia.

Climate change and environmental sustainability assessment are essential in city planning, design, and smart city advancement. Despite Saudi Arabia's high global greenhouse gas (GHG) emissions ranking, a comprehensive review of extant studies revealed insufficient tools enhancing the policymaking and comprehension of climate change and environmental performance. This paper developed a hybrid green city index (GCI) and grey relational analysis (GRA) composite index for appraising national environmental sustainability via a robust, efficient, effective, and replicable grading process. The index is designed based on two primary considerations. The first is the selection of quality underlying indicators/categories, while the second is the adoption of GRA for conducting the normalization, weighting and aggregation process. These two considerations influenced the proposed composite index, which was later applied to Saudi Arabia as a study area. The results revealed that the environmental sustainability of Saudi Arabia is not significant, with the most outstanding of 0.3127 for 2010. At the category level, the favourable environmental sustainability ranking is between the 2010 and 2012 assessment period, with a gradual decline till 2018. This study's findings are unique as no studies within the context of Saudi Arabia and the Gulf region have utilized this study's research approach. Although not all indicators of the proposed index were used in the study area, this study's methodology and outcomes have the beneficial impact of assisting Saudi Arabia's decision-makers across the cities in monitoring the status and progress of implementing its net zero carbon emissions by 2060.

Tuning PVDF Membrane Porosity and Wettability Resistance via Varying Substrate Morphology for the Desalination of Highly Saline Water.

Here, we report the fabrication of a series of highly efficient polyvinylidene fluoride (PVDF) membranes via substrate morphology variations. A wide range of sandpaper grit sizes (150-1200) were utilized as casting substrates. The effect of the penetration of abrasive particles present on the sandpapers on the casted polymer solution was tuned, and the impact of these particles on porosity, surface wettability, liquid entry pressure and morphology were investigated. The membrane distillation performance of the developed membrane on sandpapers was evaluated for the desalination of highly saline water (70,000 ppm). Interestingly, the utilization of cheap and widely available sandpapers as a substrate for casting can not only help in tuning the MD performance, but also in producing highly efficient membranes with stable salt rejection (up to 100%) and a 210% increase in the permeate flux over 24 h. The findings in this study will help in delineating the role of substrate nature in controlling the produced membrane characteristics and performance.

Regulating the Electron Depletion Layer of Au/V2O5/Ag Thin Film Sensor for Breath Acetone as Potential Volatile Biomarker.

Human exhaled breath has been utilized to identify biomarkers for diseases such as diabetes and cancer. The existence of these illnesses is indicated by a rise in the level of acetone in the breath. The development of sensing devices capable of identifying the onset of lung cancer or diabetes is critical for the successful monitoring and treatment of these diseases. The goal of this research is to prepare a novel breath acetone sensor made of Ag NPs/V2O5 thin film/Au NPs by combining DC/RF sputtering and post-annealing as synthesis methods. The produced material was characterized using X-ray diffraction (XRD), UV-Vis, Raman, and atomic force microscopy (AFM). The results revealed that the sensitivity to 50 ppm acetone of the Ag NPs/V2O5 thin film/Au NPs sensor was 96%, which is nearly twice and four times greater than the sensitivity of Ag NPs/V2O5 and pristine V2O5, respectively. This increase in sensitivity can be attributed to the engineering of the depletion layer of V2O5 through the double activation of the V2O5 thin films with uniform distribution of Au and Ag NPs that have different work function values.

Low Overpotential Electrochemical Reduction of CO2 to Ethanol Enabled by Cu/CuxO Nanoparticles Embedded in Nitrogen-Doped Carbon Cuboids.

The electrochemical conversion of CO2 into value-added chemicals is a promising approach for addressing environmental and energy supply problems. In this study, electrochemical CO2 catalysis to ethanol is achieved using incorporated Cu/CuxO nanoparticles into nitrogenous porous carbon cuboids. Pyrolysis of the coordinated Cu cations with nitrogen heterocycles allowed Cu nanoparticles to detach from the coordination complex but remain dispersed throughout the porous carbon cuboids. The heterogeneous composite Cu/CuxO-PCC-0h electrocatalyst reduced CO2 to ethanol at low overpotential in 0.5 M KHCO3, exhibiting maximum ethanol faradaic efficiency of 50% at -0.5 V vs. reversible hydrogen electrode. Such electrochemical performance can be ascribed to the synergy between pyridinic nitrogen species, Cu/CuxO nanoparticles, and porous carbon morphology, together providing efficient CO2 diffusion, activation, and intermediates stabilization. This was supported by the notably high electrochemically active surface area, rich porosity, and efficient charge transfer properties.

L-Cysteine Modified Chitosan Nanoparticles and Carbon-Based Nanostructures for the Intranasal Delivery of Galantamine.

The present study evaluates the use of thiolized chitosan conjugates (CS) in combination with two fundamental carbon nanoforms (carbon dots (CDs) and Hierarchical Porous Carbons (HPC)) for the preparation of intranasally (IN) administrated galantamine (GAL) nanoparticles (NPs). Initially, the modification of CS with L-cysteine (Cys) was performed, and the successful formation of a Cys-CS conjugates was verified via 1H-NMR, FTIR, and pXRD. The new Cys-CS conjugate showed a significant solubility enhancement in neutral and alkaline pH, improving CS's utility as a matrix-carrier for IN drug administration. In a further step, drug-loaded NPs were prepared via solid-oil-water double emulsification, and thoroughly analyzed by SEM, DLS, FTIR and pXRD. The results showed the formation of spherical NPs with a smooth surface, while the drug was amorphously dispersed within most of the prepared NPs, with the exemption of those systems contianing the CDs. Finally, in vitro dissolution release studies revealed that the prepared NPs could prolong GAL's release for up to 12 days. In sum, regarding the most promising system, the results of the present study clearly suggest that the preparation of NPs using both Cys-CS and CDs results in a more thermodynamically stable drug dispersion, while a zero-order release profile was achieved, which is essential to attain a stable in vivo pharmacokinetic behavior.

Prevalence of COVID-19 Infection among Patients with Diabetes and Their Vaccination Coverage Status in Saudi Arabia: A Cross-Sectional Analysis from a Hospital-Based Diabetes Registry.

Patients with diabetes have a higher risk of severe infection and mortality due to COVID-19. Considering the current limited effective pharmacological treatments, vaccination remains one of the most effective means to control the pandemic. The current study aimed to determine the prevalence of COVID-19 infection and the rate of COVID-19 vaccination coverage among patients with type 2 diabetes mellitus. The patients were identified from a diabetes hospital registry at Prince Sultan Military Medical City, Riyadh, Saudi Arabia in July 2021. The history of COVID-19 infection and the vaccination status were retrieved from the National Health Electronic Surveillance Network (HESN) program and the Seha platform, respectively. A total of 11,573 patients were included in this study (representing 99.5% of all patients in the registry). A total of 1981 patients (17.1%) had a history of confirmed COVID-19 infection. The rate of vaccination with a 1st dose was 84.8% (n = 9811), while the rate of full vaccination with the 2nd dose was 55.5% (n = 6422). The analysis showed that a higher proportion of male patients were fully vaccinated than female patients (61.0% versus 51.2%, p < 0.001). There were statistically significant differences among the age groups, with the full vaccination rate ranging from 59.0% for the 61-70-year-old age group to 49.0% for the > 80-year-old age group (p < 0.001). The patients with no previous history of COVID-19 infection were more likely to get fully vaccinated than those with a previous history of the infection (63.9% versus 14.6%, respectively, p < 0.001). The factors associated with a higher likelihood of unvaccinated status included the female gender (adjusted odds ratio (aOR) = 1.705 (95% confidence interval (CI): 1.528-1.902)), elderly patients in the age group of 61-70 (aOR (95% CI) = 1.390 (1.102-1.753)), the age group of 71-80 (aOR (95% CI) = 1.924 (1.499-2.470)) and the age group of >80 (aOR (95% CI) = 3.081 (2.252-4.214), and prior history of COVID-19 infection (aOR (95% CI) = 2.501 (2.223-2.813)). In conclusion, a considerable proportion of patients with type 2 diabetes had confirmed COVID-19 infection. Continued targeted efforts are needed to accelerate vaccination coverage rates among patients with diabetes in general and the particular subgroups identified in this study.

Selective CO2 Electrochemical Reduction Enabled by a Tricomponent Copolymer Modifier on a Copper Surface.

Electrochemical CO2 reduction over Cu could provide value-added multicarbon hydrocarbons and alcohols. Despite recent breakthroughs, it remains a significant challenge to design a catalytic system with high product selectivity. Here we demonstrate that a high selectivity of ethylene (55%) and C2+ products (77%) could be achieved by a highly modular tricomponent copolymer modified Cu electrode, rivaling the best performance using other modified polycrystalline Cu foil catalysts. Such a copolymer can be conveniently prepared by a ring-opening metathesis polymerization, thereby offering a new degree of freedom for tuning the selectivity. Control experiments indicate all three components are essential for the selectivity enhancement. A surface characterization showed that the incorporation of a phenylpyridinium component increased the film robustness against delamination. It was also shown that its superior performance is not due to a morphology change of the Cu underneath. Molecular dynamics (MD) simulations indicate that a combination of increased local CO2 concentration, increased porosity for gas diffusion, and the local electric field effect together contribute to the increased ethylene and C2+ product selectivity.

Hierarchical Porous Carbon-PLLA and PLGA Hybrid Nanoparticles for Intranasal Delivery of Galantamine for Alzheimer's Disease Therapy.

In the present study, poly(l-lactic acid) (PLLA) and poly(lactide-co-glycolide) (PLGA) hybrid nanoparticles were developed for intranasal delivery of galantamine, a drug used in severe to moderate cases of Alzheimer's disease. Galantamine (GAL) was adsorbed first in hierarchical porous carbon (HPC). Formulations were characterized by FT-IR, which showed hydrogen bond formation between GAL and HPC. Furthermore, GAL became amorphous after adsorption, as confirmed by XRD and differential scanning calorimetry (DSC) studies. GAL was quantified to be 21.5% w/w by TGA study. Adsorbed GAL was nanoencapsulated in PLLA and PLGA, and prepared nanoparticles were characterized by several techniques. Their sizes varied between 182 and 394 nm, with an exception that was observed in nanoparticles that were prepared by PLLA and adsorbed GAL that was found to be 1302 nm in size. DSC thermographs showed that GAL was present in its crystalline state in nanoparticles before its adsorption to HPC, while it remained in its amorphous phase after its adsorption in the prepared nanoparticles. It was found that the polymers controlled the release of GAL both when it was encapsulated alone and when it was adsorbed on HPC. Lastly, PLGA hybrid nanoparticles were intranasally-administered in healthy, adult, male Wistar rats. Administration led to successful delivery to the hippocampus, the brain area that is primarily and severely harmed in Alzheimer's disease, just a few hours after a single dose.

Stretchable Hydrophobic Surfaces and Self-Cleaning Applications.

Hydrophobizing of stretchable elastomer surfaces is considered and the reversible behavior of the resulting surface wetting state is examined after stretching and relaxing the hydrophobized samples. The environmental dust are analyzed in terms of elemental constitutes and size, and the dust pinning on the hydrophobized surface is measured. The dust removal mechanisms, by the water droplets on the hydrophobized surface, are investigated. We demonstrated that deposition of functionalized nano-size silica units on the elastomer surface gives rise to hydrophobicity with 135° ± 3° contact angle and low hysteresis of 3° ± 1°. Stretching hydrophobized elastomer surface by 50% (length) reduces the contact angle to 122° ± 3° and enhances the hysteresis to 6° ± 1°. However, relaxing the stretched sample causes exchanging surface wetting state reversibly. Water droplet rolling and sliding can clean the dusty hydrophobized surface almost 95% (mass ratio of the dust particles removed). Droplet puddling causes striations like structures along the droplet path and close examination of the few residues of the dust reveals that the droplet takes away considerably large amount of dust from surface.

Prevalence of primary headache among medical students at King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.

BACKGROUND: Headache is among the commonest complaints in medical students; it could be due to many physical or psychological stressors. It has two main types: primary (including tension-type, migraine, and cluster) and secondary. The aim of this study is to assess the prevalence of headache among male and female medical students. MATERIALS AND METHODS: This study was conducted at KSAU-HS, COM, in January 2018. Third- and fourth-year medical students from both genders who have experienced headache throughout their life or are experiencing it for the past 3 months were included in this study. All medical students completed filling the questionnaire, which consisted of demographical data, headache characteristics and triggers, and associated symptoms. RESULTS: A total of 264 [150 (56.81%) males and 114 (43.19%) females] students were evaluated. The prevalence of headache was 53.78%, and the prevalence of tension-type headache was 41.66%. The prevalence of migraine headache was 7.1%. Only one case of cluster headache was detected. Those who did not fit the criteria for the primary types were categorized as unspecified headache. The prevalence of unspecified headache was 3.78%. CONCLUSION: We can conclude from the study that tension-type headache is commonly reported in medical students. It is imperative to provide a stress-free study environment where students can perform more effectively, and sessions on how to reduce stress and alleviate fatigue are highly recommended.

Fragile X syndrome: a clinico-genetic study of mentally retarded patients in Kuwait.

In a prospective study in Kuwait, 182 mentally retarded male patients who fulfilled 5 or more clinical criteria of fragile X syndrome were screened using polymerase chain reaction (PCR) testing. Twenty patients (11%) were highly suspected of having fragile X syndrome due to mutation at the FRAXA locus; none had mutation at the FRAXE locus. Of these, 11 (55%) were confirmed fragile-X-positive by both cytogenetic and PCR techniques. The most frequent clinical features were: prominent forehead, high arched palate, hyperextensible joints, long ears, prominent jaw, height > 10th centile and attention-deficit hyperactivity. Less common were avoidance of eye contact (45%), autism (45%) and seizures (30%). Large testes were found in 55% of cases. Pre-pubertal and post-pubertal clinical criteria were different.

Staining of inclusion bodies and reticulocytes: a modified procedure.

A simple and rapid method is described for staining inclusion bodies and reticulocytes, using new methylene blue in combination with isopropyl alcohol. The morphological definition of preparations is improved, and equal to preparations stained by previous methods.