22,675 results on '"Majid M"'
Search Results
2. Hyperthermia and biological investigation of a novel magnetic nanobiocomposite based on acacia gum-silk fibroin hydrogel embedded with poly vinyl alcohol
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Zeinab Pajoum, Hooman Aghamirza Moghim Aliabadi, Adibeh Mohammadi, Zahra Sadat, Amir Kashtiaray, Milad Salimi Bani, Mohammadali Shahiri, Mohammad Mahdavi, Reza Eivazzadeh-Keihan, Ali Maleki, and Majid M. Heravi
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Acacia hydrogel ,Silk fibroin ,Biological activity ,Hyperthermia ,Poly vinyl alcohol ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
The design and synthesis of biocompatible nanostructures for biomedical applications are considered vital challenges. Herein, a nanobiocomposite based on acacia hydrogel, natural silk fibroin protein, and synthetic protein fibers of polyvinyl alcohol was fabricated and magnetized with iron oxide nanoparticles (Fe3O4 MNPs). The structural properties of the hybrid nanobiocomposite were investigated by essential analyses such as Fourier Transform Infrared Spectrometer (FTIR), Field emission scanning electron microscopy (FE-SEM), and X-ray powder diffraction)XRD(analyses, Thermogravimetric and Differential thermogravimetric analysis (TGA-DTG), Vibrating-sample magnetometry (VSM), and Energy Dispersive X-Ray Analysis (EDX). The biological activities and functional properties of the prepared magnetic nanobiocomposite were studied. Results proved that this nanobiocomposite is non-toxic to the healthy HEK293T cell line. In addition, the synthesized nanobiocomposite showed an approximately 22 % reduction in cell viability of BT549 cells after 72 h. All results confirmed the anti-cancer properties of nanobiocomposite against breast cancer cell lines. Therefore, the prepared nanobiocomposite is an excellent material that can use for in-vivo application. Finally, the hyperthermia application was evaluated for this nanobiocomposite. The SAR was measured 93.08 (W/g) at 100 kHz.
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- 2024
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3. Facile Cu–MOF-derived Co3O4 mesoporous-structure as a cooperative catalyst for the reduction nitroarenes and dyes
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Masoume Malmir, Majid M. Heravi, and Elham Shafiei Toran Poshti
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Medicine ,Science - Abstract
Abstract The present study describes the environmentally friendly and cost-effective synthesis of magnetic, mesoporous structure-Co3O4 nanoparticles (m-Co3O4) utilizing almond peel as a biotemplate. This straightforward method yields a material with high surface area, as confirmed by various characterization techniques. Subsequently, the utilization of m-Co3O4, graphene oxide (GO), Cu(II)acetate (Cu), and asparagine enabled the successful synthesis of a novel magnetic MOF, namely GO–Cu–ASP–m-Co3O4 MOF. This catalyst revealed remarkable stability that could be easily recovered using a magnet for consecutive use without any significant decline in activity for eight cycles in nitro compound reduction and organic dye degradation reactions. Consequently, GO–Cu–ASP-m-Co3O4 MOF holds immense potential as a catalyst for reduction reactions, particularly in the production of valuable amines with high industrial value, as well as for the elimination of toxic-water pollutants such as organic dyes.
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- 2024
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4. Sulfonic acid-functionalized chitosan–metal–organic framework composite for efficient and rapid conversion of fructose to 5-hydroxymethylfurfural
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Sima Darvishi, Samahe Sadjadi, and Majid M. Heravi
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Medicine ,Science - Abstract
Abstract In pursuit of designing a bio-based catalyst for the dehydration of biomass (i.e., fructose) to 5-hydroxymethylfurfural, a novel catalytic composite was prepared by in-situ formation of an Al-based metal–organic framework in the presence of chitosan. To enhance the acidity of the as-prepared catalyst, it was sulfonated with chlorosulfonic acid. Various characterization techniques, including XRD, XPS, FTIR, SEM/EDX, TGA, and elemental mapping analysis were applied to validate the formation of the acidic composite. Fructose dehydration conditions were also optimized using Response Surface Method (RSM) and it was found that reaction in the presence of catalyst (23 wt%) in DMSO, at 110 °C for 40 min led to the formation of HMF in 97.1%. Noteworthy, the catalyst was recyclable and stable up to five runs with a minor reduction in its activity.
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- 2024
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5. Clinical characteristics and outcomes of COVID-19 cases admitted to adult intensive care units during the pandemic: A single center experience
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Majid M. Alshamrani, Aiman El-Saed, Abdulrahman Alalmai, Mohammed Abdulrahman Almanna, Saad Mohammed Dhafer Alqahtani, Mohammed Saad Asiri, Sulaiman Saleh Almasoud, and Fatmah Othman
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COVID-19 ,Intensive care ,Outcome ,Risk factors ,Mortality ,Ventilation ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Background: COVID-19 is the largest recorded pandemic in history. It causes several complications such as shock, pneumonia, acute respiratory distress syndrome, and organ failure. The objective was to determine COVID-19 outcomes and risk factors in the intensive care (ICU) setting. Methods: A retrospective review of prospectively collected data was conducted. Adult patients with a positive RT-PCR test for COVID-19 admitted to ICUs of a tertiary care hospital between 2020 and 2022 were included. Patients who had severe complex trauma were excluded. The outcomes examined included ventilation use and duration, length of stay (LOS), and mortality. Results: A total of 964 patients were included. The mean ( ± standard deviation, SD) age was 63.7 ± 16.9 years. The majority of the patients were males (59.0 %) and Saudi (75.7 %). Ventilation use was documented in 443 (57.1 %) patients, with a mean ( ± SD) ventilation duration of 9.7 ± 8.4 days. Death occurred in 361 (37.4 %) patients after a mean ( ± SD) of 33.3 ± 44.5 days from infection. The mean ( ± SD) LOS was 30.6 ± 54.1 days in hospital and 5.2 ± 5.4 days in ICU. Ventilation use was associated with older age, males, longer ICU LOS, mortality, and admission to medical-surgical ICU. Crude mortality use was associated with older age, longer ICU LOS, use of ventilator, shorter ventilation duration, and admission to medical-surgical or respiratory ICUs. Conclusions: COVID-19 patients admitted to adult ICUs are at high risk of death and mechanical ventilation. The crude risks of both outcomes are higher in older age and longer ICU LOS and are very variable by ICU type.
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- 2024
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6. Clay-supported bio-based Lewis acid ionic liquid as a potent catalyst for the dehydration of fructose to 5-hydroxymthylfurfural
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Soheila Yaghoubi, Samahe Sadjadi, Xuemin Zhong, Peng Yuan, and Majid M. Heravi
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Medicine ,Science - Abstract
Abstract Caffeine and halloysite nanoclay mineral that are bio-based compounds were utilized to synthesize a novel Lewis acid heterogeneous catalyst. To this aim, halloysite was functionalized with 2,4,6-trichloro-1,3,5-triazine and reacted with caffeine, which was then converted to ionic liquid via a reaction with ZnCl2. The catalyst was applied for promoting the dehydration of fructose to 5-hydroxymethylfurfural. To investigate the effects of the reaction variables, response surface methodology was used. The product was achieved in 98.5% in 100 min using a catalyst loading of 30 wt% at 100 °C. Moreover, the catalyst was recyclable up to six runs with slight zinc leaching. Comparison of the catalytic activity of the catalyst with that of halloysite and a control catalyst with one caffeine-based Lewis acid ionic liquid confirmed the superior activity of the former and the important role of 2,4,6-trichloro-1,3,5-triazine for increasing the number of the grafted caffeine and thus the acidic sites of the catalyst. A plausible reaction mechanism was proposed, and the activity of the catalyst for other carbohydrates was also studied. According to the results, this catalyst catalyzed the reaction of other substrates to furnish 5-hydroxymethylfurfural in low to moderate yields. According to the kinetic studies, the activation energy was estimated to be 22.85 kJ/mol.
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- 2024
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7. Influence of Fire-Flame Temperature and Duration on the Behavior of Reinforced Concrete Beams with Construction Joints
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Ahmed A. Abbood and Majid M. Kharnoob
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Construction joint ,Finite element method ,Elevated temperature ,Fire duration ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Structural members' durability and strength depend on the member’s fire resistance. This study simulates the structural response of a reinforced concrete beam with a construction joint exposed to fire. The commercial finite element software ABAQUS was used to validate the laboratory findings. The testing program tested five reinforced concrete beams with the dimensions of (200x300x2700 mm), having identical reinforcing details and a concrete compressive strength (fc'=35 MPa). These beams had a 45° angled connection at the center. Four beams were exposed to fire flames at two temperature levels (600 °C and 800 °C) and for 1.0 and 2.0 hr. periods, respectively. The fifth beam is the control beam that was not exposed to fire. Laboratory results show that the worst exposure on the beam’s construction joint was at 800 °C with an exposure period of 2 hrs. This exposure reduces the bond between the joint’s two surfaces, creating a slipping effect in which disconnection occurs after loading. After 1 and 2 hours of exposure to fire at 600 °C, the residual flexural strength was 85% and 72% of that of the control beam, respectively. Whereas, beams exposed to fire for 1 and 2 hours at 800 °C showed flexural strengths lower than the control beam at 41% and 28%, respectively. Regarding the modulus of elasticity and compressive strength, they both showed residual values of (63.5, 59.2, 50.9, and 47%), and (28, 25, 19, and 16%), respectively.
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- 2024
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8. Novel preventive bundle for multidrug-resistant organisms in intensive care setting; tertiary care experience
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Majid M. Alshamrani, Aiman El-Saed, Mohammed Al Zunitan, Mohammed Abalkhail, Doris Abagguey, and Fayssal M. Farahat
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Bundle ,Multidrug-resistant organisms ,Antimicrobial use ,Environmental cleaning ,Contact isolation ,Hand hygiene ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Background: A widely-accepted standardized preventive bundle targeting multidrug-resistant organisms (MDROs) is lacking. The objective was to describe the components, implementation, compliance, and impact of a novel MDROs bundle in intensive care units (ICUs). Methods: Cohort study of surveillance activities on the components of MDROs bundle (July 2019 to June 2022) and the incidence of MDROs (April 2016 to June 2022). The implementation of MDROs bundle were preceded by ICPs-led education of the staff working in target ICUs about the importance and components of the MDROs bundle. These included the overall use of antimicrobials, appropriate environmental cleaning, appropriate contact precautions, and hand hygiene compliance. Results: During implementation, the overall use of antimicrobials was 57.8 days of therapy per 100 patient-days (44,492/76,933). It was higher in adult compared with pediatric/neonatal ICUs (p
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- 2024
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9. Symptomatic MERS-CoV infection reduces the risk of future COVID-19 disease; a retrospective cohort study
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Aiman El-Saed, Fatmah Othman, Henry Baffoe-Bonnie, Rawabi Almulhem, Muayed Matalqah, Latifah Alshammari, and Majid M. Alshamrani
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MERS-CoV ,COVID-19 ,Cross-immunity ,Cross-protection ,Saudi Arabia ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background The general human immune responses similarity against different coronaviruses may reflect some degree of cross-immunity, whereby exposure to one coronavirus may confer partial immunity to another. The aim was to determine whether previous MERS-CoV infection was associated with a lower risk of subsequent COVID-19 disease and its related outcomes. Methods We conducted a retrospective cohort study among all patients screened for MERS-CoV at a tertiary care hospital in Saudi Arabia between 2012 and early 2020. Both MERS-CoV positive and negative patients were followed up from early 2020 to September 2021 for developing COVID-19 infection confirmed by RT-PCR testing. Results A total of 397 participants followed for an average 15 months during COVID-19 pandemic (4.9 years from MERS-CoV infection). Of the 397 participants, 93 (23.4%) were positive for MERS-CoV at baseline; 61 (65.6%) of the positive cases were symptomatic. Out of 397, 48 (12.1%) participants developed COVID-19 by the end of the follow-up period. Cox regression analysis adjusted for age, gender, and major comorbidity showed a marginally significant lower risk of COVID-19 disease (hazard ratio = 0.533, p = 0.085) and hospital admission (hazard ratio = 0.411, p = 0.061) in patients with positive MERS-CoV. Additionally, the risk of COVID-19 disease was further reduced and became significant in patients with symptomatic MERS-CoV infection (hazard ratio = 0.324, p = 0.034) and hospital admission (hazard ratio = 0.317, p = 0.042). Conclusions The current findings may indicate a partial cross-immunity, where patients with symptomatic MERS-CoV have a lower risk of future COVID-19 infection and related hospitalization. The present results may need further examination nationally using immunity markers.
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- 2023
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10. Ionothermal synthesis of magnetic N-doped porous carbon to immobilize Pd nanoparticles as an efficient nanocatalyst for the reduction of nitroaromatic compounds
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Sahar Taheri, Majid M. Heravi, and Asma Saljooqi
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Medicine ,Science - Abstract
Abstract Carbon materials play important roles as catalysts or catalyst supports for reduction reactions owing to their high porosity, large specific surface area, great electron conductivity, and excellent chemical stability. In this paper, a mesoporous N-doped carbon substrate (exhibited as N–C) has been synthesized by ionothermal carbonization of glucose in the presence of histidine. The N–C substrate was modified by Fe3O4 nanoparticles (N–C/Fe3O4), and then Pd nanoparticles were stabilized on the magnetic substrate to synthesize an eco-friendly Pd catalyst with high efficiency, magnetic, reusability, recoverability, and great stability. To characterize the Pd/Fe3O4–N–C nanocatalyst, different microscopic and spectroscopic methods such as FT-IR, XRD, SEM/EDX, and TEM were applied. Moreover, Pd/Fe3O4–N–C showed high catalytic activity in reducing nitroaromatic compounds in water at ambient temperatures when NaBH4 was used as a reducing agent. The provided nanocatalyst's great catalytic durability and power can be attributed to the synergetic interaction among well-dispersed Pd nanoparticles and N-doped carbonaceous support.
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- 2023
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11. Preparation of magnetic biochar functionalized by polyvinyl imidazole and palladium nanoparticles for the catalysis of nitroarenes hydrogenation and Sonogashira reaction
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Pourya Mohammadi, Majid M. Heravi, Leila Mohammadi, and Asma Saljooqi
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Medicine ,Science - Abstract
Abstract Catalysts are essential materials in biotechnology, medicine, industry, and chemistry. On the other hand, recycling and using waste materials is important in economic efficiency and green chemistry. Thus, biochar was prepared from the stem and roots of the Spear Thistle to recover waste. After magnetizing the biochar, its surface was modified with polyvinyl imidazole. Finally, this modified biochar was decorated with Pd nanoparticles and used as a selective and recyclable nanocatalyst in the hydrogenation of nitroarenes and the Sonogashira reaction. The structure of this organic–inorganic nanocatalyst has been characterized by FESEM-EDS, XRD, FT-IR, TEM, and VSM techniques. In the hydrogenation reaction with the amount of 30 mg of nanocatalyst, the temperature of 50 °C in the water solvent, the reaction efficiency reached 99% for 30 min. In addition, under optimal conditions for the Sonogashira reaction: 1.0 mmol iodobenzene, 1.2 mmol phenylacetylene, 20 mg MBC-PVIm/Pd, 2 mmol K2CO3 in H2O at 50 C for 15 min, the reaction efficiency reached 95%. The recyclability of magnetic nanocatalysts was investigated and recognized this nanocatalyst can be used several times without notable loss of its activity.
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- 2023
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12. Efficient oxidation of sulfides to sulfoxides catalyzed by heterogeneous Zr-containing polyoxometalate grafted on graphene oxide
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Zahra Yekke-Ghasemi, Majid M. Heravi, Masoume Malmir, and Masoud Mirzaei
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Medicine ,Science - Abstract
Abstract In this study, a tri-component composite named Zr/SiW 12 /GO was meticulously prepared through an ultrasonic-assisted method. This composite incorporates zirconium nanoparticles (Lewis acid), a negatively charged Keggin type polyoxometalate, and graphene oxide, and serves as a remarkable heterogeneous catalyst. The Keggin component plays multiple roles as reducing, encapsulating, and bridging agents, resulting in a cooperative effect among the three components that significantly enhances the catalytic activity. The catalytic performance of Zr/SiW 12 /GO was thoroughly investigated in the oxidation of sulfides to sulfoxides under mild conditions, employing H2O2 as the oxidant. Remarkably, this composite exhibited exceptional stability and could be effortlessly recovered and reused up to four times without any noticeable loss in its catalytic activity.
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- 2023
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13. Effect of feeding ratio on the growth of common carp cultivated in earthen ponds
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Majid M. Taher, Sadiq J. Muhammed, Osamah A. Salih, Adel Y. Al-Dubakel, and Ahmed M. Mojer
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Feeding rate ,final weight ,daily growth rate ,feed conversion rate ,Agriculture (General) ,S1-972 ,Animal culture ,SF1-1100 ,Aquaculture. Fisheries. Angling ,SH1-691 - Abstract
The current experiment was conducted in earthen ponds at the Agricultural Research Station belonging to the Aquaculture Unit- Agriculture College at Basrah University, Al-Hartha District about 16 km northern-east of Basrah Governorate (30o39`20.264"N, 47o 44`51.533"E) from 25th July to 23rd October 2021. The feeding experiment begin after ten days of fish acclimation. Six small earthen ponds (600 m2) were used for the current experiment to investigate the differences in growth criteria for 200 individuals of common carp fed (2 T1, 3 T2 and 4 T3) % of total fish weight. Fishes were fed daily on commercial pellets manufactured by Agricultural Consultant Office belonging to Agriculture College. The total length and weight of fish were measured at the beginning and the end of the experiment, while subsamples of fish were weighed periodically and daily food changed after each weighing. Initial fish weights were 530.0± 132.7, 513.4±118.3 and 477.3±122.5 for T1, T2 and T3 respectively. Daily feed was divided into three meals, the first given early in the morning, the second at mid-day and the third given in the afternoon. Results of current experiments showed a high growth rate (FW= 1341.4 g, WI= 873.0 g, DGR=9.59 g/day and SGR=1.16 %/day) for fish fed on 4% feeding ratio compared with the two feeding ratios. Feed conversion rates were 2.46, 4.01 and 3.28 for T1, T2 and T3 respectively. Statistical analysis showed that there were no significant differences (P>0.05) between values of b with value 3 (Isometric pattern of growth) of common carp before and after the experiment. Statistical analysis of three models for condition factor proved that there were significant differences (P≤0.05) between the values before the experiment with values after the experiment, while there were no significant differences (P>0.05) after the experiment between different condition factors for common carp reared on different feeding ratio.
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- 2023
14. Awareness of health care workers with appropriate infection control practices related to multi-patient use of Close Loop Medication Administration device
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Kassem Abou Yassine, Aiman El-Saed, Fatmah Othman, Sarr Ramou, Bassam H. Al Alwan, Kholoud Ameer, Mustafa Hawthan, Mohammed Al Zunitan, and Majid M. Alshamrani
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Infection control ,Healthcare workers ,Infection ,Portable computerized devices ,Awareness ,Saudi Arabia ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Summary: Background: Portable computerized devices represent a potential source of healthcare infections. The objective was to assess the knowledge, attitudes, and practices (KAP) of healthcare workers (HCWs) toward infection control practices used with Close Loop Medication Administration (CLMA) devices. Additionally, to quantify the impact of education and training on the bacterial burden on CLMA devices. Methods: The study design consisted of two steps: a cross-sectional study was conducted among HCWs working in a tertiary care center in Riyadh, Saudi Arabia. A 32-item questionnaire was used to assess KAP information. The second step was environmental samples collected from the surfaces of CLMA devices before and after implementing a multifaceted intervention. Result: A total of 325 HCWs were included in the study. The mean age was 32.6±7.4 years. The majority were females (92%) and nurses (91.3%). The overall KAP score was 74.8%, 74.2% adequate knowledge, 79.3% positive attitude, and 71.3% appropriate practices. KAP score was better (≥ median KAP score) among HCWs working in laboratory and organ transplant units (P
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- 2023
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15. Tuning the acidity of halloysite by polyionic liquid to develop an efficient catalyst for the conversion of fructose to 5-hydroxymethylfurfural
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Samahe Sadjadi, Soheila Yaghoubi, Xuemin Zhong, Peng Yuan, and Majid M. Heravi
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Medicine ,Science - Abstract
Abstract In an attempt to prepare a low-cost and efficient acidic heterogeneous catalyst for the conversion of fructose to 5-hydroxymethylfurfural under mild reaction conditions, the acidity of halloysite was improved by covalent grafting of an acidic polyionic liquid. More precisely, halloysite was first vinyl functionalized and then polymerized with vinyl imidazole and 2-acrylamido-2-methylpropanesulfonic acid. The tangling imidazole rings were further converted to acidic ionic liquids by treating them with chlorosulfuric acid. UV–Vis spectroscopy and Hammett equation confirmed that conjugation of acid polyionic liquid resulted in the increase of the acidity of halloysite. Investigation of the efficiency of the catalyst for the synthesis of 5-hydroxymethylfurfural and optimization of reaction variables showed that 5-hydroxymethylfurfural was yielded in 97.8% after 30 min under the optimum conditions, i.e. catalyst loading of 20 wt% at 70 °C. Notably, the catalyst was highly reusable and it could be reused for at least seven reaction runs with insignificant loss of its activity. Furthermore, this catalyst could also promote the conversion of sucrose and maltose to give moderate yields of 5-hydroxymethylfurfural.
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- 2023
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16. Elasto-plastic analysis and optimal design of composite integral abutment bridge extended with limited residual plastic deformation
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Majid M. Rad, Ferenc Papp, Sarah K. Ibrahim, János Szép, Dániel Gosztola, and Dániel Harrach
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Medicine ,Science - Abstract
Abstract Due to the growing significance of structural theories concerning the composite structure analysed and designed plastically, this paper introduces a new optimisation method for controlling the plastic behaviour of a full-scale composite integral abutment bridge by employing complementary strain energy of residual forces that existed within the reinforcing rebars. Composite bridges are structures made of components such as steel and concrete, which are frequent and cost-effective building methods. Thus, various objective functions were used in this work when applying optimum elasto-plastic analysing and designing the composite integrated bridge structure that was tested experimentally in the laboratory. In contrast, the plastic deformations were constrained by restricting the complementary strain energy of the residual internal forces aiming to find the maximum applied load and the minimum number of steel bars used to reinforce the concrete column part of the structure. The numerical model employed in this paper was validated and calibrated using experimental results, which were considered inside ABAQUS to produce the validated numerical model, using concrete damage plasticity (CDP) constitutive model and concrete data from laboratory testing to solve the nonlinear programming code provided by the authors. This paper presents a novel optimization method using complementary strain energy to control the plastic behaviour of a full-scale composite integral abutment bridge, with the original contribution being the incorporation of residual forces within reinforcing rebars to limit plastic deformations. Following that, a parametric investigation of the various optimisation problems revealed how models performed variously under different complementary strain energy values, which influenced the general behaviour of the structure as it transitioned from elastic to elasto-plastic to plastic; also results showed how the complementary strain energy value is connected with the amount of damaged accrued in both concrete and steel.
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- 2023
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17. Distribution and the trend of airborne particles and bio-aerosol concentration in pediatric intensive care units with different ventilation setting at two hospitals in Riyadh, Saudi Arabia
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Waleed Alghamdi, Abdullatif A. Neamatallah, Majid M. Alshamrani, Fahad Al Mehmadi, and Aiman El-Saed
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Bacterial ,Fungal ,Fine particles ,Coarse particles ,High efficiency particular air ,Protective environment ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Objective: To examine the distribution and the trend of airborne particles and bio-aerosol concentration in pediatric intensive care units (PICUs) in two tertiary care hospitals with different ventilation setting. Methods: Hospitals A but not B is provided with a central HEPA filter. PICUs in both hospitals were categorized into protective environment (PE) with room HEPA filter, semi-protective environment (SPE) with portable air-purifier, and non-protective environment (NPE) with neither system. Fine particles (≤ 2.5 µm) and coarse particles (≤ 10.0 µm) were obtained using optical particle counter (Lighthouse Handheld 3016) and total bacterial (TBC) and fungal (TFC) counts were obtained using Andersen air sampler. Results: Hospital B had significantly higher levels of fine and coarse particles (in all room), TBC (in PE), but not TFC compared with matched rooms in hospital A. In hospital B, the levels of fine particles, coarse particles, and TBC were lowest in SPE (p
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- 2023
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18. Call for emergency action to restore dietary diversity and protect global food systems in times of COVID-19 and beyond: Results from a cross-sectional study in 38 countries
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Maha Hoteit, Reem Hoteit, Ayoub Aljawaldeh, Kathleen Van Royen, Sara Pabian, Paulien Decorte, Isabelle Cuykx, Lauranna Teunissen, Charlotte De Backer, Ina Bergheim, Raphaela Staltner, Amanda Devine, Ros Sambell, Ruth Wallace, Sabika Salem Allehdan, Tariq Abdulkarim Alalwan, Mariam Ahamad Al-Mannai, Gaëlle Ouvrein, Karolien Poels, Heidi Vandebosch, Katrien Maldoy, Christophe Matthys, Tim Smits, Jules Vrinten, Ann DeSmet, Nelleke Teughels, Maggie Geuens, Iris Vermeir, Viktor Proesmans, Liselot Hudders, Marcia Dutra De Barcellos, Cristina Ostermann, Ana Luiza Brock, Cynthia Favieiro, Rafaela Trizotto, Isadora Stangherlin, Anthonieta Looman Mafra, Marco Antônio Correa Varella, Jaroslava Varella Valentova, Maryanne L. Fisher, Melanie MacEacheron, Katherine White, Rishad Habib, David S. Dobson, Berta Schnettler, Ligia Orellana, Edgardo Miranda-Zapata, Angela Wen-Yu Chang, Wen Jiao, Matthew Tingchi Liu, Klaus G. Grunert, Rikke Nyland Christensen, Lucia Reisch, Meike Janssen, Victoria Abril-Ulloa, Lorena Encalada, Iman Kamel, Annukka Vainio, Mari Niva, Laura Salmivaara, Johanna Mäkelä, Kaisa Torkkeli, Robert Mai, Pamela Kerschke Risch, Efthymios Altsitsiadis, Angelos Stamos, Andreas Antronikidis, Maeve Henchion, Sinead McCarthy, Mary McCarthy, Alessandra Micalizzi, Peter J. Schulz, Manuela Farinosi, Hidenori Komatsu, Nobuyuki Tanaka, Hiromi Kubota, Reema Tayyem, Narmeen J. Al-Awwad, Nahla Al-Bayyari, Mohammed O. Ibrahim, Fadwa Hammouh, Somaia Dashti, Basma Dashti, Dhuha Alkharaif, Amani Alshatti, Maryam Al Mazedi, Rania Mansour, Elissa Naim, Hussein Mortada, Yareni Yunuen Gutierrez Gomez, Kelly Geyskens, Caroline Goukens, Rajshri Roy, Victoria Egli, Lisa Te Morenga, Mostafa Waly, Radwan Qasrawi, Motasem Hamdan, Rania Abu Sier, Diala Abu Al Halawa, Hazem Agha, María Reyna Liria Domínguez, Lita Palomares, Grazyna Wasowicz, Hiba Bawadi, Manal Othman, Jaafar Pakari, Allam Abu Farha, Rasha Abu-El-Ruz, Dacinia Crina Petrescu, Ruxandra Malina Petrescu Mag, Felix Arion, Stefan Cristian Vesa, Majid M. Alkhalaf, Khlood Bookari, Jamila Arrish, Zackaria Rahim, Roy Kheng, Yandisa Ngqangashe, Zandile June-Rose Mchiza, Marcela Gonzalez-Gross, Lisset Pantoja-Arévalo, Eva Gesteiro, Yolanda Ríos, Peter Yiga, Patrick Ogwok, Denis Ocen, Michael Bamuwamye, Haleama Al Sabbah, Zainab Taha, Leila Cheikh Ismail, Ayesha Aldhaheri, Elisa Pineda, Marisa Miraldo, Dawn Liu Holford, and Hilde Van den Bulck
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COVID-19 ,Pandemics ,Food consumption pattern ,Dietary diversity ,Food consumption score ,Food-related behaviors ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Background: The COVID-19 pandemic has revealed the fragility of the global food system, sending shockwaves across countries' societies and economy. This has presented formidable challenges to sustaining a healthy and resilient lifestyle. The objective of this study is to examine the food consumption patterns and assess diet diversity indicators, primarily focusing on the food consumption score (FCS), among households in 38 countries both before and during the first wave of the COVID-19 pandemic. Methods: A cross-sectional study with 37 207 participants (mean age: 36.70 ± 14.79, with 77 % women) was conducted in 38 countries through an online survey administered between April and June 2020. The study utilized a pre-tested food frequency questionnaire to explore food consumption patterns both before and during the COVID-19 periods. Additionally, the study computed Food Consumption Score (FCS) as a proxy indicator for assessing the dietary diversity of households. Findings: This quantification of global, regional and national dietary diversity across 38 countries showed an increment in the consumption of all food groups but a drop in the intake of vegetables and in the dietary diversity. The household's food consumption scores indicating dietary diversity varied across regions. It decreased in the Middle East and North Africa (MENA) countries, including Lebanon (p
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- 2023
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19. Performance of Lightning Potential Index, Lightning Threat Index, and the Product of CAPE and Precipitation in the WRF Model
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Narges Saleh, Maryam Gharaylou, Majid M. Farahani, and Omid Alizadeh
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lightning prediction ,lightning potential index (LPI) ,lightning threat index (LTI) ,product of CAPE and precipitation ,world wide lightning location network (WWLLN) ,WRF model ,Astronomy ,QB1-991 ,Geology ,QE1-996.5 - Abstract
Abstract Lightning is a naturally occurring phenomenon with significant socioeconomic and environmental impacts, underlining the need for the application of advanced methods to predict it. This study aims to evaluate the performance of the Weather Research and Forecasting (WRF) model in the prediction of the lightning potential index (LPI), the lightning threat index (LTI), and the product of convective available potential energy (CAPE) and precipitation (CAPE × P). Based on the intensity of convection and the number of lightning flashes, we simulated seven thundercloud events that occurred in Tehran between 2008 and 2013. The simulated LPI, LTI, and CAPE × P values are compared both qualitatively and quantitatively against ground‐based lighting data obtained from the world wide lightning location network (WWLLN). LPI, LTI, and CAPE × P predict the location of lightning with relatively good accuracy, although LPI outperforms LTI and CAPE × P. We also compared the simulated area‐averaged LPI, LTI, and CAPE × P against the number of lightning flashes from the WWLLN data, based on which LPI shows a better performance. Overall, LPI can be used as an effective index for the prediction of lightning. As LPI is based on cloud microphysics and LTI and CAPE × P are thermodynamic‐based methods, a better performance of LPI implies that a method based on the microphysical approach can better predict lightning. The performance of LPI, LTI, and CAPE × P is also sensitive to the horizontal resolution of model simulations, with a considerable improvement in simulations with higher horizontal resolutions.
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- 2023
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20. Chitosan bead containing metal–organic framework encapsulated heteropolyacid as an efficient catalyst for cascade condensation reaction
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Samahe Sadjadi, Neda Abedian-Dehaghani, Abolfazl Heydari, and Majid M. Heravi
- Subjects
Medicine ,Science - Abstract
Abstract Using cyclodextrin and chitosan that are bio-based compounds, a novel bi-functional catalytic composite is designed, in which metal–organic framework encapsulated phosphomolybdic acid was incorporated in a dual chitosan-cyclodextrin nanosponge bead. The composite was characterized via XRD, TGA, ICP, BET, NH3-TPD, FTIR, FE-SEM/EDS, elemental mapping analysis and its catalytic activity was examined in alcohol oxidation and cascade alcohol oxidation–Knoevenagel condensation reaction. It was found that the designed catalyst that possess both acidic feature and redox potential could promote both reactions in aqueous media at 55 °C and various substrates with different electronic features could tolerate the aforementioned reactions to furnish the products in 75–95% yield. Furthermore, the catalyst could be readily recovered and recycled for five runs with slight loss of the catalytic activity. Notably, in this composite the synergism between the components led to high catalytic activity, which was superior to each component. In fact, the amino groups on the chitosan served as catalysts, while cyclodextrin nanosponge mainly acted as a phase transfer agent. Moreover, measurement of phosphomolybdic acid leaching showed that its incorporation in metal–organic framework and bead structure could suppress its leaching, which is considered a drawback for this compound. Other merits of this bi-functional catalyst were its simplicity, use of bio-based compounds and true catalysis, which was proved via hot filtration.
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- 2023
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21. Ionic liquid-loaded triazine-based magnetic nanoparticles for promoting multicomponent reaction
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Kosar Kafshdarzadeh, Masoume Malmir, Zahra Amiri, and Majid M. Heravi
- Subjects
Medicine ,Science - Abstract
Abstract A novel hybrid magnetic ionic-liquid as a heterogeneous catalyst was synthesized by hybridization of imidazolium based-ionic liquid onto the nitrogen rich magnetic nanocomposite. The resulting catalyst (n-Fe3O4@SiO2-TA-SO3H IL) has two advantages besides recyclability: (i) high capacity of functional-SO3H group with imidazolium-IL cation for promoting symmetric and asymmetric Hantzsch reaction and (ii) easy recovery. Caused by the polymeric and magnetic nature of the n-Fe3O4@SiO2-TA-SO3H IL, large quantities of acidic groups were bound to the n-Fe3O4@SiO2-TA surface, which reduced the catalyst mass applied to the catalytic reaction. Moreover, superior catalytic performance and outstanding recyclability of n-Fe3O4@SiO2-TA-SO3H IL in mild condition make this method a green pathway for manufacture of satisfactory chemicals.
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- 2022
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22. The preparation of polyvinyl imidazole-functionalized magnetic biochar decorated by silver nanoparticles as an efficient catalyst for the synthesis of spiro-2-Amino-4H-pyran compounds
- Author
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Leila Mohammadi, Majid M. Heravi, Asma Saljooqi, and Pourya Mohammadi
- Subjects
Medicine ,Science - Abstract
Abstract The silver nanoparticle was synthesized by developing poly (1-vinylimidazole) on the surface of magnetized biochar (the stem and roots of Spear Thistle) (biochar/Fe3O4/PVIm/Ag). This nanocomposite was characterized by Fourier-transformed infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM–EDS), and transmission electron microscopy (TEM). The SEM and TEM images of the nanocatalyst, biochar/Fe3O4/PVIm/Ag-NPs, confirmed the observation of microscopic sheets of biochar. The catalytic activity of these Ag NPs was tested via multicomponent reaction plus reusing to successful formation of 2-amino-4H-pyran and functionalized spirochromen derivatives. The prepared nanocatalyst was easily separated by an external magnet and reused in repeating coupling reaction cycles four times without remarkable activity loss. The catalyst showed great efficiency and reusability, thus making it an ideal candidate for catalytic purposes in several organic transformations.
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- 2022
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23. Direction of theoretical and experimental investigation into the mechanism of n-HA/Si-PA-SC@Ag as a bio-based heterogeneous catalyst in the reduction reactions
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Zohreh Nouripour Sisakhti, Masoume Malmir, Masoumeh Bagheri Bisafar, Majid M. Heravi, and Tayebeh Hosseinnejad
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Medicine ,Science - Abstract
Abstract In the present study, a natural-based heterogeneous catalyst is synthesized. For this purpose, nano-hydroxyapatite (n-HA) is prepared, silica-modified and functionalized with phthalimide. Finally, Ag2+ was immobilized onto n-HA/Si-PA-SC and reduced to Ag nanoparticles by Bellis perennis flowers extract. n-HA/Si-PA-SC@Ag characterized by TGA, FTIR, SEM/EDX, XRD, TEM, BET and ICP-AES techniques. Moreover, metal–ligand interactions in n-HA/Si-PA-SC@Ag complex models were assessed to make a quantitative representation for the immobilization behavior of Ag NPs on the surface of n-HA/Si-PA-SC through quantum chemistry computations. Furthermore, the performance of n-HA/Si-PA-SC@Ag was studied in the nitroarene, methylene blue and congo red reductions. Finally, the recyclability study as well as Ag-leaching verified that, n-HA/Si-PA-SC@Ag was stable and reused-up to four times without losing its activity.
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- 2022
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24. Heteroployacid on the composite of boehmite and polyionic liquid as a catalyst for alcohol oxidation and tandem alcohol oxidation Knoevenagel condensation reactions
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Neda Abedian-Dehaghani, Samahe Sadjadi, and Majid M. Heravi
- Subjects
Medicine ,Science - Abstract
Abstract Using boehmite as an available and low-cost natural compound, a bi-functional catalytic composite is prepared through vinyl-functionalization of boehmite, followed by polymerization with the as-prepared bis-vinylimidazolium bromide ionic liquid and supporting of phosphotungstic acid. The catalyst was characterized via ICP, XRD, TGA, FTIR, SEM/EDS and elemental mapping analysis and applied for promoting alcohol oxidation reaction and one-pot tandem alcohol oxidation/Knoevenagel condensation reaction in aqueous media under mild reaction condition. The results indicated high catalytic activity of the catalyst for both reactions. This protocol showed high generality and aliphatic, aromatic and heterocyclic alcohols could be applied as substrates to furnish the corresponding products in high to excellent yields. Furthermore, hot filtration test confirmed true heterogeneous nature of the catalysis. The catalyst could also be recovered readily and reused for at least five runs of the reaction with low loss of the activity and phosphotungstic acid leaching upon each run.
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- 2022
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25. Pd on cyclotriphosphazen-hexa imine decorated boehmite as an efficient catalyst for hydrogenation of nitro arenes under mild reaction condition
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Samahe Sadjadi, Neda Abedian-Dehaghani, and Majid M. Heravi
- Subjects
Medicine ,Science - Abstract
Abstract Cyclotriphosphazen-hexa imine ligand was prepared through successive reactions of phosphonitrilchloride trimer with 4-hydroxybenzaldehyde and (3-aminopropyl) triethoxy silane. The as-prepared ligand was then covalently grafted on boehmite to furnish an efficient support for the immobilization of Pd nanoparticles and synthesis of a novel heterogeneous catalyst for hydrogenation of nitro arenes. The catalytic tests revealed that the catalyst had excellent catalytic activity for hydrogenation of various nitro arenes with different steric and electronic features under mild reaction condition in aqueous media. Noteworthy, the catalyst was highly selective and in the substrates with ketone or aldehyde functionalities, reduction of nitro group was only observed. The catalyst was also recyclable and only slight loss of activity was detected after each recycling run. Hot filtration test also approved true heterogeneous nature of catalysis.
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- 2022
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26. Synthesis of Ag nanoparticles by Celery leaves extract supported on magnetic biochar substrate, as a catalyst for the reduction reactions
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Sahar Taheri, Majid M. Heravi, and Pourya Mohammadi
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Medicine ,Science - Abstract
Abstract Green synthesis of a noble metal such as Ag nanoparticles is an enormously developed research area. In this study, a biochar/Fe3O4–Ag magnetic nanocatalyst was produced via a green path by using Celery stalk as a carbon-based substrate and Celery leaf extract as reducing and stabilizing agents to construct Ag nanoparticles. The synthesized nanocatalyst was determined using various techniques, such as UV–Vis spectroscopy, FT-IR spectroscopy, XRD (X-ray diffraction), SEM/EDX spectroscopy (scanning electron microscopy/energy-dispersive X-ray), TEM (transmission electron microscopy), and VSM (vibrating sample magnetometer). To survey the catalytic action of the biochar/Fe3O4–Ag nanocatalyst, it was used in the reduction reaction of disparate nitroaromatics, aldehydes, and ketones. This catalyst has demonstrated good characteristics in terms of the amount, reusability, recoverability, activity, and structural integrity of the catalyst during the reaction. In addition, biochar/Fe3O4–Ag could be detached magnetically and recycled multiple times without significantly reducing its catalytic performance.
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- 2022
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27. Incorporating heterogeneous lacunary Keggin anions as efficient catalysts for solvent-free cyanosilylation of aldehydes and ketones
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Masoume Malmir, Majid M. Heravi, Zahra Yekke-Ghasemi, and Masoud Mirzaei
- Subjects
Medicine ,Science - Abstract
Abstract Polyoxometalates (POMs) as efficient catalysts can be used a wide range of chemical transformations due to their tunable Brønsted/Lewis-acidity and redox properties. Herein, we reported two hybrid and heterogeneous lacunary Keggin catalysts: (TBA)7[PW11O39] (TBA-PW 11 ) and (TBA)8[SiW11O39]·4H2O (TBA-SiW 11 ) (TBA+: tetrabutylammonium) in which [XW11O39]n− anions were coated by TBA+ cations. In this form, TBA+ can easily trap reactants on the surface of the catalysts and increase the catalytic reaction. Therefore, the catalytic performance of both POMs was tested in cyanosilylation of numerous compounds bearing-carbonyl group and trimethylsilyl cyanide under solvent-free conditions. TBA-PW 11 is more effective than TBA-SiW 11 , conceivably due to the higher Lewis acidity of the P than the Si center and to the higher accessibility of the metal centers in the framework structure. Noteworthy, the recyclability and heterogeneity of both POMs catalysts were also examined, and the results confirmed that they remain active at least after three recycling procedures.
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- 2022
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28. Lanthanoid-containing polyoxometalate nanocatalysts in the synthesis of bioactive isatin-based compounds
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Mansoureh Daraie, Masoud Mirzaei, Maryam Bazargan, Vadjiheh Sadat Amiri, Bita Abdolahi Sanati, and Majid M. Heravi
- Subjects
Medicine ,Science - Abstract
Abstract Lanthanoid-containing polyoxometalates (Ln-POMs) have been developed as effective and robust catalysts due to their Lewis acid–base active sites including the oxygen-enriched surfaces of POM and the unique 4f. electron configuration of Ln. As an extension of our interest in Ln-POMs, a series of as-synthesized nanocatalysts K15[Ln(BW11O39)2] (Ln-B 2 W 22 , Ln = La, Ce, Nd, Sm, Gd, and Er) synthesized and fully characterized using different techniques. The Ln3+ ion with a big ionic radius was chosen as the Lewis acid center which is sandwiched by two mono-lacunary Keggin [BW11O39]9− units to form Ln-containing sandwiched type cluster. Consequently, the catalytic activity of nanocatalysts with different Ln was examined in the synthesis of bioactive isatin derivatives and compared under the same optimized reaction conditions in terms of yields of obtained products, indicating the superiority of the nano-Gd-B 2 W 22 in the aforementioned simple one-pot reaction. The effects of different dosages of nanocatalyst, type of solvent, reaction time, and reaction temperature in this catalytic system were investigated and the best results were obtained in the presence of 10 mol% of nano-Gd-B 2 W 22 in water for 12 min at the reflux condition.
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- 2022
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29. Perspectives and practices of dietitians with regards to social/mass media use during the transitions from face-to-face to telenutrition in the time of COVID-19: A cross-sectional survey in 10 Arab countries
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Khlood Bookari, Jamila Arrish, Majid M. Alkhalaf, Mudi H. Alharbi, Sara Zaher, Hawazin M. Alotaibi, Reema Tayyem, Narmeen Al-Awwad, Radwan Qasrawi, Sabika Allehdan, Haleama Al Sabbah, Sana AlMajed, Eiman Al Hinai, Iman Kamel, Jalila El Ati, Ziad Harb, The Arabic Dietitians practices (ADP) survey Group, and Maha Hoteit
- Subjects
COVID-19 ,dietitians ,social media ,mass media ,telenutrition ,barriers ,Public aspects of medicine ,RA1-1270 - Abstract
During the COVID-19 pandemic, most healthcare professionals switched from face-to-face clinical encounters to telehealth. This study sought to investigate the dietitians’ perceptions and practices toward the use of social/mass media platforms amid the transition from face-to-face to telenutrition in the time of COVID-19. This cross-sectional study involving a convenient sample of 2,542 dietitians (mean age = 31.7 ± 9.5; females: 88.2%) was launched in 10 Arab countries between November 2020 and January 2021. Data were collected using an online self-administrated questionnaire. Study findings showed that dietitians’ reliance on telenutrition increased by 11% during the pandemic, p = 0.001. Furthermore, 63.0% of them reported adopting telenutrition to cover consultation activities. Instagram was the platform that was most frequently used by 51.7% of dietitians. Dietitians shouldered new difficulties in dispelling nutrition myths during the pandemic (58.2% reported doing so vs. 51.4% pre-pandemic, p
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- 2023
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30. Pd on thermo-responsive composite of silica-coated carbon nanotube and 1-vinyl-3-butylimidazolium-based ionic liquid copolymers as an efficient catalyst for hydrogenation of nitro compounds
- Author
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Samahe Sadjadi, Neda Abedian-Dehaghani, and Majid M. Heravi
- Subjects
Medicine ,Science - Abstract
Abstract In this work, an ionic liquid-containing thermo-responsive heterogeneous catalyst with utility for promoting hydrogenation of nitro-compounds in aqueous media is developed. To prepare the catalyst, silica-coated carbon nanotubes were synthesized and vinyl-functionalized. The resulted compound was then polymerized with 1-viny-3-butylimidazolium bromide and N-isopropylacrylamide. The obtained ionic liquid-containing thermo-responsive composite was palladated via wet-impregnation method to give the final catalyst. Study of the performance of the catalyst confirmed high catalytic activity of the catalyst at temperature above the lower critical solution temperature. Furthermore, the catalyst was highly recyclable and showed negligible Pd leaching upon recycling. Broad substrate scope and selectivity of the catalyst towards reduction of nitro functionality were also confirmed. Furthermore, hot filtration test implied the heterogeneous nature of the catalysis. The comparison of the activity of Pd/CNT-P with some control catalysts approved the importance of hybridization of P and CNT and the presence of ionic liquid for the catalytic activity.
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- 2022
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31. A novel composite of ionic liquid-containing polymer and metal–organic framework as an efficient catalyst for ultrasonic-assisted Knoevenagel condensation
- Author
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Samahe Sadjadi, Fatemeh Koohestani, and Majid M. Heravi
- Subjects
Medicine ,Science - Abstract
Abstract 1-Butyl-3-vinylimidazolium chloride was synthesized and polymerized with acrylamide to furnish an ionic liquid-containing polymer, which was then used for the formation of a composite with iron-based metal–organic framework. The resultant composite was characterized with XRD, TGA, FE-SEM, FTIR, EDS and elemental mapping analyses and its catalytic activity was appraised for ultrasonic-assisted Knoevenagel condensation. The results confirmed that the prepared composite could promote the reaction efficiently to furnish the corresponding products in high yields in very short reaction times. Moreover, the composite exhibited high recyclability up to six runs. It was also established that the activity of the composite was higher compared to pristine metal–organic framework or polymer.
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- 2022
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32. Design and Optimization of Enhanced Magnitude and Phase Response IIR Full-Band Digital Differentiator and Integrator Using the Cuckoo Search Algorithm
- Author
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Jehad I. Ababneh and Majid M. Khodier
- Subjects
Digital differentiator ,digital integrator ,linear phase ,cuckoo search algorithm ,optimization ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Design of full-band infinite impulse response (IIR) digital differentiator (DD) and digital integrator (DI) based on the Lk-norm and the min-max optimality criteria have been demonstrated in literature. However, the designed IIR DDs and DIs using these criteria do not have linear phase or have unsatisfactory magnitude response. In this paper, a novel approach to design, optimize and improve the magnitude response and the linearity of the phase response of IIR DD and DI using the cuckoo search (CS) optimization algorithm is proposed. The proposed approach is based on a varied Lk-norm where $k$ linearly increases with the number of the frequency samples between the values 1 and 2. The design and optimization of DDs and DIs are carried out using the CS optimization method due to its simplicity, efficiency, and robustness in solving general multidimensional optimization problems. The performance of the designed DDs and DIs using the proposed approach is compared with designs based on different criteria and algorithms available in literature. The comparison shows that the designed DDs and DIs based on the proposed approach have better phase responses and better or at least comparable magnitude responses compared to those of DDs and DIs designed using other methods in the literature.
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- 2022
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33. Investigation of halloysite nanotubes and Schiff base combination with deposited copper iodide nanoparticles as a novel heterogeneous catalytic system
- Author
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Mansoureh Daraie, Donya Bagheri, Masoume Malmir, and Majid M. Heravi
- Subjects
Medicine ,Science - Abstract
Abstract The design, preparation and characterization of a novel composite based on functionalization of halloysite nanoclay with Schiff base followed by immobilization of copper iodide as nanoparticles is revealed. This novel nano composite was fully characterized by utilization of FTIR, SEM/EDX, TGA, XRD and BET techniques. This Cu(I) NPs immobilized onto halloysite was successfully examined as a heterogeneous, thus easily recoverable and reusable catalyst in one of classist organic name reaction so-called “Click Reaction”. That comprised a three component reaction of phenylacetylene, α-haloketone or alkyl halide and sodium azide in aqueous media to furnish 1,2,3‐triazoles in short reaction time and high yields. Remarkably, the examination of the reusability of the catalyst confirmed that the catalyst could be reused at least six reaction runs without appreciable loss of its catalytic activity.
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- 2021
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34. Cage Culture in Iraq, Current Status & Potential: A Review
- Author
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Nader A. Salman, Khalil I. Saleh, and Majid M. Taher
- Subjects
Carp fish ,Culturists problems ,Feed ,Floating cages ,Agriculture (General) ,S1-972 - Abstract
The present investigation aimed at discussing the present status of cage culture in Iraq and its future potential. Iraqi water resources can provide the basic requirements for successful fish culture in cages. Environmental conditions may maintain sustainable growth rate for 10 months at least. This has encouraged the investors and fish culturists to adopt such technique and make use of its advantages. Development of cage culture in Iraq has been reviewed from the early seventies till now. Fish production from cage culture was analyzed focusing upon recent developments in terms of fish consumption criteria and the per capita in Iraq. The floating cages culture system is considered now as the main culture system, because environmental conditions are suitable for cage culture more than the earthen ponds and recirculating systems. Cage culture industry relies on row materials that are locally available. They includes, frames, bridges, passage ways, nets, floating materials, feeders and wave breakers. Most of the cage units are locally manufactured from steel or wooden frame in square or rectangular shapes. Some circular and octahedral units are used in Kurdistan and Mosul. Researches on cage culture continued to optimize parameters such as stocking density, feeding and stocking sizes, stocking density of fish in the cages was fixed at 60-70 fish per m3 or 1500-2000 fish per cage of 1.5 x 4 x 4m using fish of 100 g in weight. Problems facing cage culture in Iraq are summarized by high prices of feeds, viral infection and other fish diseases, deterioration of water quality, the policy of importing fish from neighboring countries and lack of skills among farmers. Solutions for the above problems and recommendations for future development are discussed at the end of the article.
- Published
- 2022
35. Managing critical care during COVID-19 pandemic: The experience of an ICU of a tertiary care hospital
- Author
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Hasan M. Al-Dorzi, Abdulaziz S. Aldawood, Amal Almatrood, Victoria Burrows, Brintha Naidu, John D. Alchin, Haifaa Alhumedi, Nabeeha Tashkandi, Hamdan Al-Jahdali, Arif Hussain, Mohammed K. Al Harbi, Muayed Al Zaibag, Salih Bin Salih, Majid M. Al Shamrani, Abdulmohsen Alsaawi, and Yaseen M. Arabi
- Subjects
Severe acute respiratory infection ,COVID-19 ,Saudi Arabia ,Critical care ,Disease outbreak ,Disaster planning ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Background: The COVID-19 pandemic has strained ICUs worldwide. To learn from our experience, we described the critical care response to the outbreak. Methods: This is a case study of the response of the Intensive Care Department (75-bed capacity) at a tertiary-care hospital to COVID-19 pandemic, which resulted in a high number of critically ill patients. Results: Between March 1 and July 31, 2020, 822 patients were admitted to the adult non-cardiac ICUs with suspected (72%)/confirmed (38%) COVID-19. At the peak of the surge, 125 critically ill patients with COVID-19 were managed on single day. To accommodate these numbers, the bed capacity of 4 ICUs was increased internally from 58 to 71 beds (+40%) by cohorting 2 patients/room in selected rooms; forty additional ICUs beds were created in 2 general wards; one cardiac ICU was converted to managed non-COVID-19 general ICU patients and one ward was used as a stepdown for COVID-19 patients. To manage respiratory failure, 53 new ICU ventilators, 90 helmets for non-invasive ventilation and 47 high-flow nasal cannula machines were added to the existing capacity. Dedicated medical teams cared for the COVID-19 patients to prevent cross-contamination. The nurse-to-patient and RT-to-patient ratio remained mostly 1:1 and 1:6, respectively. One-hundred-ten ward nurses were up-skilled to care for COVID-19 and other ICU patients using tiered staffing model. Daily executive rounds were conducted to identify patients for transfer and at least 10 beds were made available for new COVID-19 admissions/day. The consumption of PPE increased multiple fold compared with the period preceding the pandemic. Regular family visits were not allowed and families were updated daily by videoconferencing and phone calls. Conclusions: Our ICU response to the COVID-19 pandemic required almost doubling ICU bed capacity and changing multiple aspects of ICU workflow to be able to care for high numbers of affected patients.
- Published
- 2021
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36. Magnetic composite of γ-Fe2O3 hollow sphere and palladium doped nitrogen-rich mesoporous carbon as a recoverable catalyst for C–C coupling reactions
- Author
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Masoume Malmir, Majid M. Heravi, Zahra Amiri, and Kosar Kafshdarzadeh
- Subjects
Medicine ,Science - Abstract
Abstract In this article, palladated-magnetic nitrogen doped porous carbon was prepared from nano magnetic γ-Fe2O3 hollow sphere (h-Fe2O3) with high specific surface area and pore volume. To the purpose, initially h-Fe2O3 was prepared and covered with glucose via hydrothermal treatment with subsequent polymerization of organic shell. The polymerization of melamine-resorcinol–formaldehyde (MRF) was achieved in the presence of Cl-functionalized glucose coated h-Fe2O3 (h-Fe2O3@glu-MRF). Next, the prepared magnetic core–shell hollow sphere was palladated followed by carbonization to yield Pd@h-Fe2O3@C introducing more pores in its structure. The resulted compound, Pd@h-Fe2O3@C, was fully characterized, showing that carbonization process expressively increased the specific surface area. The resulted Pd@h-Fe2O3@C was successfully used for promoting C–C coupling reactions under mild reaction conditions as a heterogeneous catalyst and its activity was compared with some prepared control catalysts. This novel catalyst was magnetically separated simply by a magnet bar and recycled and reused at least in five consecutive runs, without considerable loss of its activity. It is note mentioning that, high recyclability with low Pd leaching are another gains of this protocol.
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- 2021
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37. Nursing strategic pillars to enhance nursing preparedness and response to COVID-19 pandemic at a tertiary care hospital in Saudi Arabia
- Author
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Nabeeha Tashkandi, Maha Aljuaid, Theolinda McKerry, John Alchin, Laura Taylor, Elmer J. Catangui, Rana Mulla, Suwarnnah Sinnappan, Georges Nammour, Aiman El-Saed, and Majid M. Alshamrani
- Subjects
COVID-19 ,Preparedness ,Nursing strategies ,Pandemic ,Saudi Arabia ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Background: COVID-19 pandemic caused enormous implications on the frontline staff. The objective was to share our nursing experience in responding to COVID-19 pandemic at a large hospital and its impact on nursing safety and healthcare services. Methods: Six nursing strategic pillars were implemented. Pillar 1: establishing corona command centre. Pillar 2: limiting exposure by virtual care model, strict infection control measures, altered patient flow, active surveillance, and contact tracing. Pillar 3: maintaining sufficient supplies of personal protective equipment. Pillar 4: creating surge capacity by establishing dedicated COVID-19 units and increasing critical care beds. Pillar 5: training and redeployment of nurses and implementing alternate staffing models. Pillar 6: monitoring staff wellbeing, establishing mental health support hotline and clinic, providing hotel self-quarantine, and financial incentives. Results: Out of 5483 nurses, 543 (10%) were trained for redeployment, mainly at acute and intensive care units. After serving 11,623 infected patient including 1646 hospitalizations during the first 9 months of the pandemic, only 385 (7.0%) nurses were infected with COVID-19. Out of them, only 10 (2.6%) required hospitalization, one (0.3%) required ICU admission, and none died. Although the number of patients hospitalized at our hospital during the current pandemic was 17 folds higher than the 2015 outbreak of middle East respiratory syndrome coronavirus, the hospital administration did not have to close the hospital as they did in 2015. Conclusions: Proactive nursing leadership and implementation of multiple nursing pillars enabled the facility to maintain the safety of nursing workforce while serving large influx of COVID-19 patients.
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- 2021
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38. The role of nanoparticles in plant biochemical, physiological, and molecular responses under drought stress: A review
- Author
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Adnan Rasheed, Huijie Li, Majid M. Tahir, Athar Mahmood, Muhammad Nawaz, Adnan Noor Shah, Muhammad Talha Aslam, Sally Negm, Mahmoud Moustafa, Muhammad Umair Hassan, and Ziming Wu
- Subjects
antioxidant ,drought stress ,genes expression ,nanoparticles ,photosynthesis ,Plant culture ,SB1-1110 - Abstract
Drought stress (DS) is a serious challenge for sustaining global crop production and food security. Nanoparticles (NPs) have emerged as an excellent tool to enhance crop production under current rapid climate change and increasing drought intensity. DS negatively affects plant growth, physiological and metabolic processes, and disturbs cellular membranes, nutrient and water uptake, photosynthetic apparatus, and antioxidant activities. The application of NPs protects the membranes, maintains water relationship, and enhances nutrient and water uptake, leading to an appreciable increase in plant growth under DS. NPs protect the photosynthetic apparatus and improve photosynthetic efficiency, accumulation of osmolytes, hormones, and phenolics, antioxidant activities, and gene expression, thus providing better resistance to plants against DS. In this review, we discuss the role of different metal-based NPs to mitigate DS in plants. We also highlighted various research gaps that should be filled in future research studies. This detailed review will be an excellent source of information for future researchers to adopt nanotechnology as an eco-friendly technique to improve drought tolerance.
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- 2022
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39. Monosubstituted Keggin as heterogeneous catalysts for solvent-free cyanosilylation of aldehydes and ketones
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Zahra Yekke-Ghasemi, Majid M. Heravi, Masoume Malmir, and Masoud Mirzaei
- Subjects
Zirconium substituted Keggin ,Heterogeneous catalyst ,Solvent-free ,Cyanosilylation ,TMSCN ,Chemistry ,QD1-999 - Abstract
Any successful catalyst should have a dedicated synthesizing route considering their high yields, time-efficient, and do not require any highly toxic chemicals. In this regard, two nano-sized monosubstituted polyoxometalates (POMs) with the well-known Keggin structure were synthesized and characterized: (TBA)4[Zr(OH)PW11O39]·22H2O (TBA-ZrPW11) and (TBA)5[Zr(OH)SiW11O39]·17H2O (TBA-ZrSiW11) (TBA+: tetrabutylammonium). Thus, the catalytic activities of both catalysts were tested in the cyanosilylation reaction without any solvents of various aldehydes and ketones with trimethylsilyl cyanide (TMSCN) over two heterogeneous catalysts. Finally, the recyclability and heterogeneity of these POM-based catalysts were also checked, showing that they remain active at least after three recycling procedures.
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- 2022
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40. Lactation alters the relationship between liver lipid synthesis and hepatic fat stores in the postpartum period
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Maria A. Ramos-Roman, Majid M. Syed-Abdul, Brian M. Casey, Jeffry R. Alger, Yu-Lun Liu, and Elizabeth J. Parks
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hormones ,lipogenesis ,liver metabolism ,mammary gland ,nonesterified fatty acids ,pregnancy ,Biochemistry ,QD415-436 - Abstract
In mothers who are nursing their infants, increased clearance of plasma metabolites into the mammary gland may reduce ectopic lipid in the liver. No study to date has investigated the role of lactation on liver lipid synthesis in humans, and we hypothesized that lactation would modify fatty acid and glucose handling to support liver metabolism in a manner synchronized with the demands of milk production. Lactating (n = 18) and formula-feeding women (n = 10) underwent metabolic testing at 6-week postpartum to determine whether lactation modified intrahepatic triacylglycerols (IHTGs), measured by proton magnetic resonance spectroscopy. Subjects ingested oral deuterated water to measure fractional de novo lipogenesis (DNL) in VLDL-TG during fasting and during an isotope-labeled clamp at an insulin infusion rate of 10 mU/m2/min. Compared with formula-feeding women, we found that lactating women exhibited lower plasma VLDL-TG concentrations, similar IHTG content and similar contribution of DNL to total VLDL-TG production. These findings suggest that lactation lowers plasma VLDL-TG concentrations for reasons that are unrelated to IHTG and DNL. Surprisingly, we determined that the rate of appearance of nonesterified fatty acids was not related to IHTG in either group, and the expected positive association between DNL and IHTG was only significant in formula-feeding women. Further, in lactating women only, the higher the prolactin concentration, the lower the IHTG, while greater DNL strongly associated with elevations in VLDL-TG. In conclusion, we suggest that future studies should investigate the role of lactation and prolactin in liver lipid secretion and metabolism.
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- 2022
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41. Risk of COVID-19 morbidity and mortality among healthcare workers working in a Large Tertiary Care Hospital
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Majid M. Alshamrani, MD, Aiman El-Saed, MD, PhD, Mohammed Al Zunitan, MD, Rawabi Almulhem, RN, PHN, and Saad Almohrij, MD
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Coronavirus disease (COVID-19) ,pandemic ,hospital ,healthcare ,Saudi Arabia ,Infectious and parasitic diseases ,RC109-216 - Abstract
ABSTRACT: OBJECTIVES: To estimate COVID-19 infection and outcomes among healthcare workers (HCWs) compared with non-HCWs. METHODS: A prospective surveillance study was conducted among HCWs and non-HCWs eligible for treatment at a large tertiary care facility in Riyadh between March 1st to November 30th, 2020. RESULTS: A total 13,219 cases with confirmed COVID-19 have been detected during the study; 1596 (12.1%) HCW patients (HCWPs) and 11623 (87.9%) non-HCWPs. Infection per 100 population was almost ten-fold higher in HCWs compared with non-HCWs (9.78 versus 1.01, p
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- 2021
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42. Clinical characteristics and outcomes of community-acquired pneumonia in western Saudi Arabia: A four-year retrospective analysis of medical records
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Fayssal M. Farahat, Omar K. Bukhari, Ibrahim A. Basfar, Ammar M. Alammari, Ahmed Z. Zaatari, Asim A. Alsaedi, and Majid M. Alshamrani
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Community acquired pneumonia ,Epidemiology ,Diagnosis ,Antimicrobial use ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Background: Community-acquired pneumonia (CAP) is a significant cause of morbidity and mortality, especially for the elderly and people who suffer from chronic conditions. This study was conducted to assess the clinical and microbiological characteristics and disease outcomes associated with the occurrence of CAP. Methods: This retrospective chart review was conducted at King Abdulaziz Medical City, Jeddah, Saudi Arabia. Cases with documented clinical diagnosis of CAP during the period from 2016 to 2019 were included. Data were collected on demographic, clinical, and microbiological characteristics, used antimicrobials and patients’ outcomes, including length of hospital stay, intensive care unit admission, and mortality. Multivariate regression analysis was performed to identify risk factors for increased length of hospital stay. Results: A total of two hundred and eighteen CAP episodes were identified. Patients had a median age of 64.5 years, and 54.1% were males. Microbiological diagnosis was established in 33 patients (15.1%). Admission to ICU and diagnosis of a neurological disease were significantly associated with longer hospital stay (>7 days). An average of 2.7 antimicrobials were used per patient, and the most common antibiotics used were Piperacillin/Tazobactam (46.3%), Doxycycline (44%), then Ceftriaxone (42.7%). Four patients (1.8%) died during hospital stay. Conclusions: This retrospective analysis of CAP cases identified a lack of microbiological diagnosis and increased burden associated with disease severity and the need for hospitalization. The ability to identify CAP at an earlier stage will be a cornerstone to mitigate its impact on the healthcare system and ICU units.
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- 2021
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43. Silver incorporated into g-C3N4/Alginate as an efficient and heterogeneous catalyst for promoting click and A3 and KA2 coupling reaction
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Mansoureh Daraie, Majid M. Heravi, Pourya Mohammadi, and Ali Daraie
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Medicine ,Science - Abstract
Abstract Fe3O4/g-C3N4/Alginate-Ag nanocomposite as a novel and effective nanocatalyst was successfully prepared. This nanocomposite was fully characterized using several techniques such as X‐ray diffraction (XRD), field emission scanning electron microscopy with energy dispersive spectroscopy (FESEM-EDS), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR). In addition, the catalytic activity of this novel and characterized nanocatalyst was investigated in the regioselective synthesis of 1,4-disubstituted 1,2,3-triazoles via click reaction and A3 and KA2 coupling reaction in aqueous media. The prepared nanocatalyst was simply recovered by using an external magnet and reused for several times with a slight loss of catalytic activity.
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- 2021
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44. In situ decoration of Au NPs over polydopamine encapsulated GO/Fe3O4 nanoparticles as a recyclable nanocatalyst for the reduction of nitroarenes
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Saba Hemmati, Majid M. Heravi, Bikash Karmakar, and Hojat Veisi
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Medicine ,Science - Abstract
Abstract A new and efficient catalyst has been designed and prepared via in situ immobilization of Au NPs fabricated polydopamine (PDA)-shelled Fe3O4 nanoparticle anchored over graphene oxide (GO) (GO/Fe3O4@PDA/Au). This novel, architecturally interesting magnetic nanocomposite was fully characterized using different analytical techniques such as Field Emission Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, elemental mapping, Transmission Electron Microscopy, Fourier Transformed Infrared Spectroscopy, X-ray Diffraction and Inductively Coupled Plasma-Atomic Electron Spectroscopy. Catalytic activity of this material was successfully explored in the reduction of nitroarenes to their corresponding substituted anilines, using NaBH4 as reducing agent at ambient conditions. The most significant merits for this protocol were smooth and clean catalysis at room temperature with excellent productivity, sustainable conditions, ease of separation of catalyst from the reaction mixture by using a magnetic bar and most importantly reusability of the catalyst at least 8 times without any pre-activation, minimum loss of activity and considerable leaching.
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- 2021
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45. Post-vaccination SARS-CoV-2 infection among healthcare workers in tertiary care hospitals in Saudi Arabia: A case series
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Majid M. Alshamrani, Fayssal M Farahat, Aiman El-Saed, Mohammed Alzunitan, Asim Alsaedi, Ayman El Gammal, Wafaa Al Nasser, Syed Nazeer, and Saad A. Almohrij
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Coronavirus disease (COVID-19) ,Pandemic ,Hospital ,Healthcare ,Saudi Arabia ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Healthcare workers have been categorized among the priority groups for COVID-19 vaccination. However, post-vaccination infections have been identified. This study was conducted to investigate SARS-CoV-2 infection among healthcare workers (HCWs) who received the COVID-19 vaccine. A case series in a multicenter healthcare system in Saudi Arabia was created from HCWs who had (PCR-RT) confirmed SARS-CoV-2 infection after at least one dose of Pfizer-BioNTech vaccination. A total of 20 healthcare workers (HCWs) have been included. The majority (70.0%) were males and the average age was 39.4 ± 10.1 years. They included physicians (55.0%), nurses (25.0%) and other HCWs (20.0%). Eighteen (90%) HCWs had infection after the first dose; 47.1% within the first week, 41.2% within the second week, and 11.8% within the third week. Only two HCWs (10.0%) had infection one week after the second dose. The majority (63.2%) had mild (52.6%) or moderate (10.3%) disease with no severe disease or hospitalization. The majority of post-vaccination COVID-19 infections among HCWs occurred before the full protection of the vaccine is gained. Suspicion of COVID-19 infection should be considered even with a history of COVID-19 vaccination. Recently vaccinated HCWs should be advised to fully comply with all recommended precautions to prevent COVID-19 transmission.
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- 2022
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46. Pd NPs supported on halloysite functionalized with Schiff base as an efficient catalyst for Sonogashira reaction
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Mansoureh Daraie, Majid M. Heravi, Yalda Rangraz, and Zahra Besharati
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Medicine ,Science - Abstract
Abstract A hybrid system was designed and synthesized through reacting modified halloysite (Hal-Cl) with Schiff base (DAB-PC) and applied as catalytic support for anchoring Pd NPs to afford Pd@Hal-DAB-PC catalyst. The resultant material was well identified by various analyses including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction patterns (XRD), thermogravimetric analysis (TGA), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and inductively coupled plasma-optical emission spectrometry (ICP-OES) and revealed outstanding catalytic activity in the Sonogashira reaction in aqueous media. Also, This nanocatalyst was simply collected and recycled up to six runs with a slight drop in efficiency, indicating the durability of Pd@Hal-DAB-PC.
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- 2021
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47. High Burden of Resistant Gram Negative Pathogens Causing Device-associated Healthcare Infections in a Tertiary Care Setting in Saudi Arabia, 2008-2016
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Hanan H. Balkhy, Aiman El-Saed, Majid M. Alshamrani, Asim Alsaedi, Wafa Al Nasser, Ayman El Gammal, Sameera M. Aljohany, Yassen Arabi, Saad Alqahtani, Henry Baffoe Bonnie, Adel Alothman, and Saad A. Almohrij
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Antimicrobial resistance ,Multidrug resistance ,Device-Associated infections ,Healthcare-Associated infections ,Surveillance ,Saudi Arabia ,Microbiology ,QR1-502 - Abstract
Objectives: There is local and regional deficiency in the data examining the contribution of resistant pathogens to device-associated healthcare-associated infections (DA-HAIs). The objective was to examine such data in a multi-hospital system in Saudi Arabia in comparison with the US National Health Surveillance Network (NHSN). Methods: Surveillance of DA-HAIs was prospectively conducted between 2008 and 2016 in four hospitals of Ministry of National Guard Health Affairs. Consecutive NHSN reports were used for comparisons. Definitions and methodology of DA-HAIs and bacterial resistance were based on NHSN. Results: A total 1260 pathogens causing 1141 DA-HAI events were included. Gram negative pathogens (GNPs) were responsible for 62.5% of DA-HAIs, with a significantly higher Klebsiella, Pseudomonas, Acinetobacter, and Enterobacter than NHSN hospitals. Approximately 28.3% of GNPs and 23.5% of gram positive pathogens (GPPs) had some type of resistance. Nearly 34.3% of Klebsiella were resistant to third/fourth generation cephalosporins, 4.8% of Enterobacteriaceae were carbapenem-resistant (CRE), 24.4% of Staphylococcus aureus were methicillin-resistant (MRSA), and 21.9% of Enterococci were vancomycin-resistant (VRE). Multidrug resistance (MDR) was 65.0% in Acinetobacter, 26.4% in Escherichia coli, 23.0% in Klebsiella, and 14.9% in Pseudomonas. Resistant GNPs including cephalosporin-resistant Klebsiella, MDR Klebsiella, and MDR Escherichia coli were significantly more frequent while resistant GPPs including MRSA and VRE were significantly less frequent than NHSN hospitals. Conclusion: The current findings showed heavier and more resistant contribution of GNPs to DA-HAIs in Saudi hospitals compared with American hospitals. The higher resistance rates in Klebsiella and Escherichia coli are alarming and call for effective antimicrobial stewardship programs.
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- 2020
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48. The Effect of Some Food Additives on Growth Parameters of Grass Carp Ctenopharyngodon idella Fingerlings
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Majid M. Taher, Sadiq J. Muhammed, Ahmed M. Mojer, and Adel Y. Al-Dubakel
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GCE ,Thepax ,Endo Vit. C ,Grass carp ,Agriculture (General) ,S1-972 - Abstract
A laboratory experiment was carried out to investigate the effect of Thepax and Endo Vit. C as feed additives in the formulated diet on the growth performance of grass carp Ctenopharyngodon idella. The feed (30.11% crude protein) manufactured in the laboratory using raw local materials diet. Young grass carp (Average weight 3.36± 0.95 g) obtained from Aquaculture Unit ponds in Al-Hartha Station for Agricultural Researches, North Basrah. The fish were stocked in nine glass aquarium, three replicates for each treatment, of dimensions 60×40×30 cm provided with pumping aeration. The experimental diets included a control T1 (0% additives), T2 (1g Thepax/kg diet) and T3 (1g Endo Vit. C /kg diet) were used in feeding trail of current experiment. The experiment lasted for 57 days (from 29 Nov. to 24 Jan.) and fishes were fed six days a week using 5% of fish weight as feeding ratio. Results of current study reveals that grass carp fed on formulated feed supplemented with Endo vit. C having high growth performance (WG, DGR, RGR and SGR). The lowest Feed conversion ratio (2.511) was recorded in T3 this value was statistically significant (P≤0.05) with T2 while the highest value (2.767) was observed on the control. Protein efficiency ratio, feed intake and gross conversion efficiency were also recorded high values in T3, but control displayed superior values compared with Thepax treatment, which showed higher value of Relative feed intake compared to other two treatments.
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- 2022
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49. The prevalence of comorbidities among adult people diagnosed with HIV infection in a tertiary care hospital in western Saudi Arabia
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Fayssal M. Farahat, Yousef S. Alghamdi, Amr F. Farahat, Anhar A. Alqurashi, Abdullah K. Alburayk, Abdullah A. Alabbasi, Asim A. Alsaedi, and Majid M. Alshamrani
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HIV ,Comorbidities ,Antiretroviral therapy (ART) ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Background: The life expectancy of people living with HIV is markedly increasing with the introduction of effective antiretroviral medications. However, these patients face an increased risk of developing multi-morbidities-especially with advanced age. This study was conducted to assess the prevalence of and risk factors associated with the occurrence of chronic comorbidities among patients diagnosed with HIV infection. Methods: A retrospective chart review was conducted on the medical records of patients with HIV diagnoses from 2000 to 2018. Data were collected on age, sex, date of diagnosis, associated co-morbidities, antiretroviral medications (ART) and status at time of data collection (alive or deceased). Only adult patients 18 years or above were studied. Results: A total of 130 confirmed HIV cases were included. Patient ages ranged from 23 to 86 years old (mean ± SD 50.1 ± 12.6). Almost half of the patients (48.5%) had at least one associated comorbidity. The most common chronic comorbidity was diabetes mellitus (15.4%), followed by dyslipidemia (10.8%), hypertension (10.8%) and lymphoma (10.0%). Comorbidity proportions increased with advanced patient age (p = 0.047). Three or more comorbidities were reported in 40.7% of patients aged 60 years old or above. Using logistic regression analysis, only patients aged 50 years old or above were more likely to have at least one comorbidity (OR = 7.59, 95%CI = 2.25, 25.61). Conclusions: The burden of chronic comorbidities among people diagnosed with HIV is high, especially among older age individuals, with an increasing number of comorbidities per patient. Proper counseling for HIV patients is highly recommended-not only for prevention of other infectious diseases (e.g., vaccination) but also for lifestyle modification and self-management for those with chronic conditions.
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- 2020
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50. Pd on poly(1-vinylimidazole) decorated magnetic S-doped grafitic carbon nitride: an efficient catalyst for catalytic reduction of organic dyes
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Masoumeh Dorraj, Samahe Sadjadi, and Majid M. Heravi
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Medicine ,Science - Abstract
Abstract A novel magnetic catalyst, (SGCN/Fe3O4/PVIs/Pd) was synthesized by growing of poly(1-vinylimidazole) on the surface of ionic liquid decorated magnetic S-doped graphitic carbon nitride, followed by stabilization of palladium nanoparticles. Catalytic activity of the prepared heterogeneous catalyst was explored for the catalytic reduction of hazardous dyes, methyl orange and Rhodamine B, in the presence of NaBH4. Besides, the effects of the reaction variables on the catalytic activity were investigated in detail. The kinetics study established that dye reduction was the first order reaction and the apparent activation energy was calculated to be 72.63 kJ/mol and 68.35 kJ/mol1 for methyl orange and Rhodamine B dyes, respectively. Moreover, ΔS# and ΔH# values for methyl orange were found to be − 33.67 J/mol K and 68.39 kJ/mol respectively. These values for Rhodamine B were − 45.62 J/mol K and 65.92 kJ/mol. The recycling test verified that the catalyst possessed good stability and reusability, thereby making it a good candidate for the catalytic purposes. Furthermore, a possible catalytic mechanism for dye catalytic reduction over SGCN/Fe3O4/PVIs/Pd was proposed.
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- 2020
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