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21.
The selection of a facile, eco-friendly, and effective methodology is the need of the hour for efficient curing of the COVID-19 virus in air, water, and many food products. Recently, semiconductor-based photocatalytic methodologies have provided promising, green, and sustainable approaches to battle against viral activation via the oxidative capabilities of various photocatalysts with excellent performance under moderate conditions and negligible by-products generation as well. Considering this, recent advances in photocatalysis for combating the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are inclusively highlighted. Starting from the origin to the introduction of the coronavirus, the significant potential of photocatalysis against viral prevention and -disinfection is discussed thoroughly. Various photocatalytic material-based systems including metal-oxides, metal-free and advanced 2D materials (MXenes, MOFs and COFs) are systematically examined to understand the mechanistic insights of virus-disinfection in the human body to fight against COVID-19 disease. Also, a roadmap toward sustainable solutions for ongoing COVID-19 contagion is also presented. Finally, the challenges in this field and future perspectives are comprehensively discussed involving the bottlenecks of current photocatalytic systems along with potential recommendations to deal with upcoming pandemic situations in the future.

Photocatalysts are green, eco-friendly, clean and sustainable and could be a solution to combat COVID-19 because of potential features of various types of metal oxides against viral inactivation via the generation of reactive oxidative species.  相似文献   
22.
Aluminum waste-can management in Malaysia has recently become a serious environmental and public health issue, particularly in metropolitan areas. This has prompted the need to valorize these waste-cans into value-added products using the most economical and environmentally friendly techniques. In this study, the sol–gel technique was used to synthesize high-quality alumina from the aluminum waste-cans collected. From this method, the observed peaks of the synthesized alumina were identified as diaspore (α-AlO(OH)), boehmite (γ-AlO(OH)), aluminum oxide, or gamma-alumina (γ-Al2O3) crystalline structure and corundum. The morphological configuration, microstructure, and functional group properties of the synthesized alumina were evaluated. All the synthesized alumina exhibited a non-spherical shape and appeared to have hexagonal-like shape particles. Moreover, the XRD patterns of the synthesized alumina AL-6-30 and AL-12-30 exhibited a small angle (1–10°) with no XRD peak, which indicated a mesoporous pore structure with no long-range order. The overall results of γ-alumina synthesized from the aluminum waste-cans showed an optimal condition in producing a highly structured γ-alumina with excellent surface-area characteristics. The synthesized alumina exhibited stronger and highly crystalline functional characteristics almost comparable with the commercially available brands on the market.  相似文献   
23.
Sarcopenia is the loss of skeletal muscle mass, and is most common in older people. The present multi-center cross-sectional study aimed to determine the prevalence of sarcopenia and possible risk factors among Arab elderly females. A total of 131 ambulatory Saudi elderly females aged 60–85 years (mean age 65.9 ± 5.5 years) were recruited to participate. A general questionnaire with questions related to sociodemographic factors, medical history, diet, physical activity, and lifestyle was administered. Anthropometrics and muscle assessments were done. Fasting blood glucose and lipids were measured routinely. Circulating 25(OH)D and irisin levels were measured using commercially available assays. Sarcopenia was assessed using the criteria of the Asian Working Group for Sarcopenia (AWGS). Over-all prevalence of sarcopenia was 19.8% (26 out of 131 participants). Novel measures such as abdominal volume index (AVI), dietary fiber, and irisin were found to be significantly lower in the sarcopenia group than those without sarcopenia, independent of age. No associations were found with physical activity or dietary and lifestyle habits. In conclusion, sarcopenia is relatively common among Arab elderly females. Longitudinal studies are needed to determine whether lifestyle modifications can decrease the incidence of sarcopenia in this population. Irisin maybe a promising biomarker for sarcopenia but needs to be confirmed using larger sample sizes.  相似文献   
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PURPOSE: To characterize and compare hepatocellular carcinoma and liver metastases of colorectal metastatic cancer (CMC) by means of quantitative liver perfusion MRI. MATERIALS AND METHODS: Liver perfusion was assessed in 26 HCC and CMC patients (50 nodules) by means of contrast-enhanced MRI. Six perfusion parameters-hepatic perfusion index (HPI), mean transit time (MTT), distribution volume (DV), total blood flow (F(T)), arterial blood flow (F(A)), and portal blood flow (F(P))-were calculated in tumor nodules and the adjacent hepatic parenchyma. RESULTS: The values of F(T), F(A), F(P), and DV were significantly higher in the HCC than in the CMC group, whereas MTT was significantly higher in the CMC group. There was no significant difference in HPI. Arterial blood flow was higher than portal blood flow in the CMC group, while portal blood flow was slightly higher than arterial blood flow in the HCC group. CONCLUSION: The present work describes the use of dynamic MRI to quantitatively assess liver perfusion, which in the future may help studying liver cancers on the basis of their microvascular characteristics.  相似文献   
28.
Objectives:To elucidate the risk factors for hospital admission among COVID-19 patients with type 2 diabetes mellitus (T2DM).Methods:This retrospective study was conducted at the Prince Sultan Military Medical City, Riyadh, Saudi Arabia between May 2020 and July 2020. Out of 7,260 COVID-19 patients, 920 were identified as T2DM. After the exclusion process, 806 patients with T2DM were included in this analysis. Patients’ data were extracted from electronic medical records. A logistic regression model was performed to estimate the risk factors of hospital admission.Results:Of the total of 806 COVID-19 patients with T2DM, 48% were admitted in the hospital, 52% were placed under home isolation. Older age between 70-79 years (OR [odd ratio] 2.56; p=0.017), ≥80 years (OR 6.48; p=0.001) were significantly more likely to be hospitalized compared to <40 years. Similarly, patients with higher HbA1c level of ≥9% compared to <7%; (OR 1.58; p=0.047); patients with comorbidities such as, hypertension (OR 1.43; p=0.048), cardiovascular disease (OR 1.56; p=0.033), cerebrovascular disease (OR 2.38; p=0.016), chronic pulmonary disease (OR 1.51; p=0.018), malignancy (OR 2.45; p=0.025), chronic kidney disease (CKD) IIIa, IIIb, IV (OR 2.37; p=0.008), CKD V (OR 5.07; p=0.007) were significantly more likely to be hospitalized. Likewise, insulin-treated (OR 1.46; p=0.03) were more likely to require hospital admission compared to non-insulin treated patients.Conclusion:Among COVID-19 patients with diabetes, higher age, high HbA1c level, and presence of other comorbidities were found to be significant risk factors for the hospital admission.  相似文献   
29.
Objectives:To assess the public knowledge and perception about generic medications in Saudi Arabia, and their willingness to use generic medications.Methods:This cross-sectional, online-questionnaire-based study was conducted between May and July 2019, including participants who can read and complete an Arabic online survey. Chi-square test and contingency coefficient were used to investigate differences in different segments of participants and assess the association between knowledge and perception.Results:A total of 397 participants have completed the survey. One-half of them were female, the majority were of young age (<35 years), and 40% of them were buying their medications independently. Only 40.5% of participants had adequate knowledge and 60% of them had positive perception on generics. Participants with higher level of education were more likely to have adequate knowledge (p=0.002) and positive perception (p=0.006). The study found a moderate relationship between knowledge and perception about generics (standardized C=0.35, p<0.001). The country of origin for medications was a significant indicator of quality for two-thirds of participants, and one-half of them believed that local generics can compete with imported ones. About one-half of participants used generics and the majority of them were satisfied with their experience.Conclusion:There is a general lack of knowledge, while having a positive perception on generic medications among the general public in Saudi Arabia. Future studies should focus on strategies to improve it and assess its cost-savings consequences while maintaining quality of care.  相似文献   
30.
Purpose. To compare clinical advantages and hemodynamic and respiratory changes during one lung-collapsed ventilation (OLCV) using a double-lumen tube (DLT) or a single-lumen tube (SLT) with intrathoracic CO2 insufflation, in patients undergoing thoracic sympathectomy (TS) under general anesthesia. Methods. One hundred and twenty-five patients (94 men and 31 women) undergoing TS for the treatment of palmar hyperhidrosis (PH) were randomly allocated to two groups: group A (68 patients; age, 29 ± 6 years) in whom DLT was used, and group B (57 patients; age, 32 ± 3 years) in whom SLT with intrathoracic CO2 insufflation at a rate of 0.5–1 l·min−1 and sustained intrathoracic pressure at 6 mmHg insufflation were used. Anesthesia was maintained with 1 minimum alveolar concentration (MAC) isoflurane in 50% nitrous oxide in oxygen with incremental doses of sufentanil and atracurium when required. Arterial blood gases were measured in 10 patients in group B. Hemodynamic and respiratory parameters were obtained perioperatively. Results. There were no significant differences in hemodynamic and respiratory parameters between the two groups during the study phases, except for the arterial oxygen saturation (SpO2). The times required for anesthesia and surgery were significantly shorter in the SLT group than in the DLT group. SpO2 during OLCV was 95 ± 1% with DLT and 98 ± 1% with SLT, with a significant difference. Three patients had an SpO2 of less than 90% in the recovery room, where the chest tube position was readjusted, with no further sequelae. Conclusion. General anesthesia with SLT and intrathoracic CO2 insufflation provides optimal operating conditions, adequate oxygenation, and perfect hemodynamic stability during TS. Received: November 28, 2000 / Accepted: August 8, 2001  相似文献   
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