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Research efforts on electromagnetic interference (EMI) shielding materials have begun to converge on green and sustainable biomass materials. These materials offer numerous advantages such as being lightweight, porous, and hierarchical. Due to their porous nature, interfacial compatibility, and electrical conductivity, biomass materials hold significant potential as EMI shielding materials. Despite concerted efforts on the EMI shielding of biomass materials have been reported, this research area is still relatively new compared to traditional EMI shielding materials. In particular, a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment, preparation process, and micro-control would be valuable. The preparation methods and characteristics of wood, bamboo, cellulose and lignin in EMI shielding field are critically discussed in this paper, and similar biomass EMI materials are summarized and analyzed. The composite methods and fillers of various biomass materials were reviewed. this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.
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A condensation reaction of salicylic acid with formaldehyde in the presence of sulfuric acid led to the synthesization of the bis(2-hydroxy-3-carboxyphenyl)methane (BHCM) ligand, which was subsequently allowed to bind with nickel (II) ions. In light of the information obtained from the elemental analyses (C, H, and M), spectral (IR, MS, 1H-NMR, and UV-Vis) and thermal and magnetic measurements, the most likely structures of the ligand and complex have been identified. It has been suggested that the BHCM coordinates in a tetradentate manner with two Ni(II) ions to produce an octahedral binuclear complex. The SEM and TEM morphology of the compounds showed spherical shapes. An X-ray diffraction analysis indicated a considerable difference in the diffraction patterns between BHCM (crystalline) and Ni-BHCM (amorphous), and the Scherrer equation was used to calculate the crystallite size. Some optical characteristics were estimated from UV-Vis spectra. The ligand and its nickel(II) complex underlie the range of semiconductors. It was verified that for human lung (A-549) cancer, the BHCM compound displayed a significant barrier to the proliferation test in noncancerous cells (human lung fibroblasts, WI-38), which was also undertaken. To demonstrate the binding affinities of the chosen compounds (BHCM and Ni-BHCM) in the receptor protein's active site [PDB ID: 5CAO], a molecular docking (MD) study was carried out.
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Background: Healthcare work is a major risk for having musculoskeletal disorders (MSDs), including low back pain (LBP). This study aimed to estimate the prevalence of LBP and define its associated risk factors among resident physicians. Material and Methods: A descriptive cross-sectional survey was conducted among all resident physicians of all specialties in Abha city during the period from July 2020 to September 2020. Data were collected using an online pre-structured data collection tool. The Nordic Musculoskeletal Questionnaire (NMQ) (back pain section) was applied to assess the effect of LBP on the residents' ability to perform job duties effectively. Results: A total of 312 resident physicians responded. Their age ranged between 25 and 41 years. Males represented 57.7% of them. The prevalence of LBP was 64.7%. The most common reported aggravating factors for LBP were working in uncomfortable posture (73.3%), standing for long periods (64.4%), and long sitting sessions (51.5%). Regarding the pain-relieving factors, sleeping ranked first (60.4%), followed by taking analgesics (48.5%) and maintaining a good posture (35.6%). Multivariate logistic regression analysis revealed that obese subjects were at higher risk than underweight subjects to develop LBP (adjusted odds ratio (AOR) =6.18, 95% confidence interval (CI): 1.26-30.34, P = 0.025). Compared to resident physicians without family history of back pain, those with such history were at almost 4-fold higher risk of developing LBP (AOR = 3.90, 95% CI: 2.33-6.52, P < 0.001). Conclusion: LBP is a very prevalent problem among resident physicians, particularly obese subjects and those with family history of back pain. LBP adversely impacts the work performance of the affected physicians.
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BACKGROUND: Herbs are used worldwide as a treatment for plenty of diseases, and some herbs are used as the origin of modern medications. Although the therapeutic benefit was reported mostly from China, over time the world seemed to realize its importance. The use of herbs as medicine is also very common in the Arab region and Saudi Arabia. OBJECTIVES: This study was conducted to assess the pattern of use of herbs as medications in Saudi Arabia and factors associated with its use. METHODS: A convenience sample of adult patients in a tertiary care hospital in Jeddah, western Saudi Arabia was used. A questionnaire consisted of two sections, i.e., demographic characteristics and the knowledge, attitudes, and practices on the use of herbs. The data collection was conducted during December 2019. RESULTS: Three hundred and eighty patients were included, of which 53.3% were female. Almost half (49.7%) were college graduates. More than half of patients (55.6%) used herbs themselves, and (59%) reported members of the family used herbs for the past 12 months. Most patients (62.6%) use herbs without medical consultation. Patients used herbs following information received from family members (57.8%), social media (22.5%), doctors (8.1%), books (6.6%), or TV (5%). The most-reported herb was Anise followed by cumin and cinnamon. CONCLUSION: The use of herbs is common in Saudi Arabia. Herbs are mostly used for a variety of medical conditions following family members' experience and social media recommendations. Detailed information on the type of herbs used, doses, and effects are worth further study with a focus on variation based on different regions.