International Journal of Environmental Research and Public Health
The world is still in need of an effective therapy to treat coronavirus disease-19 (COVID-19). Th... more The world is still in need of an effective therapy to treat coronavirus disease-19 (COVID-19). This cross-sectional study was conducted on COVID-19 survivors in Saudi Arabia to investigate the influence of a healthy diet on the recovery time from COVID-19. A questionnaire was developed to assess participants’ dietary habits, based on the 2015 Dutch food-based dietary guidelines. A total of 738 COVID-19 survivors participated in the study, of whom 237 (32.1%) were hospitalized for COVID-19 treatment while 501 (76.9%) were not hospitalized, and 320 (43.4%) were females and 418 (56.6%) were males. Overall, no significant difference was noted in healthy diet score between males and females; however, this score was significantly lower for Saudis compared to non-Saudis. Among the non-hospitalized patients, eating a more healthy diet was associated with a shorter duration of recovery (p < 0.05) and was significantly affected by gender (15.8 ± 9.3 male vs. 12.1 ± 8.9 female; p < 0.001...
ISTFA 2021: Conference Proceedings from the 47th International Symposium for Testing and Failure Analysis
Semiconductor manufacturing has been outsourced to un-trusted regions due to globalization. The c... more Semiconductor manufacturing has been outsourced to un-trusted regions due to globalization. The complex multistep fabrication of micro-scale integrated circuits (ICs) and the tedious assembly of macro-scale Printed Circuit Boards (PCBs) are vulnerable to malicious attacks from design to final delivery. PCBs provide the functional connections of Integrated Circuits (ICs), sensors, power supplies, etc. of many critical electronic systems for consumers, corporations, and governments. The feature sizes of PCB signal traces in 2D and vias in 3D are an order of magnitude larger than IC devices, and are thereby more vulnerable to non-destructive attacks such as X-ray or probing. Active and passive countermeasures have been successfully developed for IC devices, however PCBs devices are difficult to wholly secure from all attacks. Passive countermeasures for X-ray attacks using high-z materials to block and scatter X-rays are effective, but there is a lack of active and passive countermeasu...
Black seeds (Nigella sativa) owe an important place due to its more demand as a food as well as m... more Black seeds (Nigella sativa) owe an important place due to its more demand as a food as well as medicine. A lack of information does exist regarding the quality and safety for market-available food-grade samples of black seed (BS). The aim of this study is to investigate the quality and standardize the BS samples according to world health organization (WHO) guidelines of instrumental analysis and pharmacological activities. Instrumental analysis was performed with the help of ASE (accelerated solvent extraction), IR (infrared spectroscopy), UHPLC (ultra-high-performance liquid chromatography) and NMR (nuclear magnetic resonance spectroscopy) whereas ash values and chemical tests were applied for physicochemical analysis. DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and cytotoxicity assay were performed as well. A high extract yield (g) with recovery of 4.4 ± 7.7 (22%) for Pakistani, 3.3 ± 4.7 (16.5%) for Indian and 3.02 ± 10...
Journal of the Pediatric Infectious Diseases Society
We describe the presentation and treatment of a patient who developed ongoing fever and diagnosed... more We describe the presentation and treatment of a patient who developed ongoing fever and diagnosed with disseminated toxoplasmosis post-hematopoietic stem cell transplantation. He was initially treated with trimethoprim-sulfamethoxazole (TMP-SMX) and there was dramatic improvement in his fever curve. He successfully completed a modified course of therapy.
In this study, we analyze the properties of boron isotope (B)-rich powders from three different s... more In this study, we analyze the properties of boron isotope (B)-rich powders from three different sources, that is, American, Cambridge, and Pavezyum, to fabricate the bulk MgB superconductors and evaluate their superconducting properties. While B-rich powder is an essential precursor to fabricate MgB superconductors for fusion magnet applications, the properties of the B powder turned out to be critical to determine the quality of the final superconducting product. Therefore, appropriate control of processing conditions is needed to comply with the requirements of the nuclear fusion application. Analysis of the B isotope ratio by accelerator mass spectroscopy and neutron transmission revealed that all three types of powder are enriched with B to better than 99 at % quality. In addition, Pavezyum's B shows the lowest crystallinity and smallest crystalline domain size as evidenced by the high-resolution X-ray diffractometer and scanning electron microscopy. The chemical states of the boron isotope investigated with near edge X-ray absorption fine structure spectroscopy and X-ray photoemission spectroscopy also reveals that Pavezyum boron has amorphous structure. MgB bulks and multi-filamentary (12-filament) wires have been manufactured, sintered at different temperatures and characterized via the transport critical current density. The wire with Pavezyum B shows three times higher current carrying capacity at a particular magnetic field compared to the wire using Cambridge B and hence, Pavezyum B boron has the potential for manufacturing fusion grade MgB based magnets. The results of this study demonstrated that Boron powders with higher purity, smaller grain size and lower crystallinity are critical for improving the superconducting and electronic properties of MgB samples fabricated from the powder. Thus, the low-neutron-activation MgB is possibly an affordable and technically viable candidate to replace NbTi superconductors in the low field poloidal field and correction coils for the next-generation fusion reactors.
Abstract Nickel oxide has tremendous applications in the field of biomedicine. In this study, NiO... more Abstract Nickel oxide has tremendous applications in the field of biomedicine. In this study, NiO nanoparticles were synthesized with different Bi contents (NiO@Bi; 0.0–7.5 wt%), and multifunctional usages were investigated. Structural confirmation was conducted through XRD and Raman studies, which revealed a monophasic cubic system. With increasing Bi content, broadening of the XRD and Raman peaks were observed, indicating a reduction in particle size. The crystallite size was found to be in the range of 10–26 nm. The decrease in particle size was confirmed through dynamic light scattering measurement. The homogeneous distribution of all elements and the presence of Bi were detected by an EDX/SEM e-mapping study. Field emission electron microscopy confirmed the formation of spherical shape nanoparticles. The grain size was reduced from 30 nm to 10 nm with Bi content, in accordance with XRD and Raman results. The Kubelka-Munk method was employed to determine the effect of Bi content on the optical band gap of NiO. The energy gap was reduced with Bi content in the range of 3.32–3.50 eV. Antimicrobial and in vitro cytotoxic characteristics of the prepared NPs were also studied. The results revealed that all NiO@Bi NPs had negligible antimicrobial activity and no cytotoxic effects on both normal and activated splenic cells. The in vivo acute cytotoxicity study indicated no cytotoxic effects on liver and kidney functions. The prepared NiO@Bi NPs were implanted in living organisms without hepatic/renal toxicity, demonstrating excellent biocompatibility, cell viability, and superior quality of nanocrystals, suggesting that the prepared NPs are ideal candidates for antibacterial and biomedical applications.
A mobile ad hoc network (MANET) may be a self-configured, infrastructure-less network of mobile n... more A mobile ad hoc network (MANET) may be a self-configured, infrastructure-less network of mobile nodes that move independently. Owing to this movement, links can change often and can require special routing techniques to handle this. Every node acts as an intermediate router to receive and transmit packets. in this paper, the impact of varying transmission range on different propagation model and queue model on 3 routing protocols specifically AODV, DSR and DYMO is analyzed. The simulations were done on Qualnet. The significant metrics used for comparative analysis are- throughput, end-to-end delay and average jitter. The nodes of designed scenario communicate all the way through constant bit rate (CBR) application traffic. It is found that AODV is best performer under CBR traffic for MANET nodes operated through Okumura Propagation Model with queue technique as well as DYMO performs well in free space propagation model using queuing technique. This paper also summarize as the node d...
Introduction: Knowledge and attitudes towards proper antibiotic usage among students in medical a... more Introduction: Knowledge and attitudes towards proper antibiotic usage among students in medical and other health allied fields play a vital role in limiting the pandemic of antibiotic resistance. This study aimed to assess knowledge and attitudes toward antibiotic usage among pre-professional students at King Saud bin Abdulaziz University for Health Sciences on Jeddah Campus, Saudi Arabia. Methods: A self-administered cross-sectional survey of 347 first year students was conducted at the College of Science and Health Professions, King Saud bin Abdulaziz University for Health Sciences using a validated questionnaire. Results: Nearly 63% of the students had a moderate level of knowledge. Two third of the students (69.7%) correctly knew that antibiotics are indicated for the treatment of bacterial infections. However, about 36% of the students incorrectly thought that antibiotics are also used to treat viral infections, while 28.5% were not sure. Only 38.8% of the students were aware o...
Colloids and Surfaces A: Physicochemical and Engineering Aspects
Abstract Zinc oxide is well-known material and used in several applications. We have synthesized ... more Abstract Zinc oxide is well-known material and used in several applications. We have synthesized the good quality ZnO nanoparticles with different concentrations of Strontium (Sr) doping for photocatalytic applications. The elemental composition and homogeneous distribution of Sr doping in ZnO was investigated through EDX/SEM mapping. The morphology of synthesize products was studied through FE-SEM and grain size was estimated. X-ray diffraction (XRD) and FT-Raman spectroscopy analyses approves the single phase and purity of synthesized Sr:ZnO NPs as no additional peak in XRD and Raman was seen. The size of crystallites was estimated using Scherrer equation and noticed to be reduced from 24 to 16 nm with rising the Sr concentration. The energy gap was estimated using Kubelka-Munk function and noticed in range from 3.25–3.27 eV with Sr concentration. The photoluminescence spectra were recorded for all Sr:ZnO NPs at λexc =350 nm. The photocatalytic activity of Sr:ZnO NPs samples was investigation by decolourization of methylene blue (MB) dye under irradiation of black-light in an aqueous solution at ambient conditions. A remarkable improvement in photocatalytic activity was obtained for the entire prepared Sr:ZnO samples compared to that of neat ZnO. Such improvement in photocatalytic activity can be attributed to the effective photogenerated charges separating, in addition to the good adsorption of MB dye molecules over Sr:ZnO NPs surface.
Silicon carbide (SiC), owing to its extraordinary chemical stability and refractory properties, i... more Silicon carbide (SiC), owing to its extraordinary chemical stability and refractory properties, is widely used in the manufacturing industry. Despite the semiconducting nature and morphology-tuned band gap, its efficacy as photocatalysts has not been thoroughly investigated. The current study reports the synthesis, characterization and the evaluation of the capability of silicon carbide for hydrogen generation from water splitting. The optical characterization of the as-synthesized powder exposed the formation of multi-wavelength absorbing entities in synthetic process. The structural analysis by XRD and the fine microstructure analysis by HRTEM revealed the cubic 3C-SiC (β-SiC) and hexagonal α-polymorphs (2H-SiC and 6H-SiC) as major and minor phases, respectively. The Mott–Schottky analysis verified the n-type nature of the material with the flat band potential of − 0.7 V. In the electrochemical evaluation, the sharp increase in the peak currents in various potential ranges, under illumination, revealed the plausible potential of the material for the oxidation of water and generation of hydrogen. The generation of hydrogen and oxygen, as a consequence of water splitting in the actual photocatalytic experiments, was observed and measured. A significant increase in the yield of hydrogen was noticed in the presence of methanol as h+ scavenger, whereas a retarding effect was offered by the Fe3+ entities that served as e− scavengers. The combined effect of both methanol and Fe3+ ions in the photocatalytic process was also investigated. Besides hydrogen gas, the other evolved gasses such as methane and carbon monoxide were also measured to estimate the mechanism of the process.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Tb-doped Y2O3 microspheres (MSs) were prepared via a homogeneous thermal degradation process at a... more Tb-doped Y2O3 microspheres (MSs) were prepared via a homogeneous thermal degradation process at a low temperature and then coated with a nanosilica shell (Y2O3:Tb@SiO2) using a sol-gel process. The core MSs were highly crystalline and spherical with a porous surface, single cubic phase, and particle size of 100-250 nm. Transmission electron microscopy (TEM) images clearly showed the spherical shape of the as-prepared core MSs, which were fully covered with a thick and mesoporous nanosilica shell. Fourier transform infrared (FTIR) spectra displayed the well-resolved infrared absorption peaks of silica (SiO, SiOSi, etc.), confirming the presence of the silica surface coating. The core MSs retained their spherical shape even after heat treatment and subsequent silica surface coating. It was observed that the core/shell MSs are easily dispersible in aqueous media and form a semi-transparent colloidal solution. Ultraviolet/visible and zeta potential studies were tested to prove the changes in the surface chemistry of the as-designed core/shell MSs and compare with their core counterpart. The growth of the amorphous silica shell not only increased the particle size but also enhanced remarkably the solubility and colloidal stability of the MSs in aqueous media. The strongest emission lines originating from the characteristic intra-shell 4f-4f electronic transitions of Tb ions were quenched after silica layer deposition, but the MSs still showed strong green (5D4 → 7F5 at 530-560 nm as most dominant) emission efficiency, which indicates great potential in fluorescent bio-probes. The emission intensity is discussed in relation to the quenching mechanism induced by surface silanol (Si-OH) groups, particle size, and surface charge.
International urology and nephrology, Jan 22, 2018
The formation of urinary stone, urolithiasis, is one the oldest known disease affecting human thr... more The formation of urinary stone, urolithiasis, is one the oldest known disease affecting human throughout different civilizations and times. The exact pathophysiological mechanism of urolithiasis is not yet clear, as these calculi are of various types and too complex for simple understanding. A single theory cannot explain its formation; therefore, different theories are presented in various times for its explanation like free particle, fixed particle, Randall's plaque theory. In addition, various factors and components are identified that play an important role in the formation of these urinary calculi. In this review, composition of kidney stones, its prevalence/incidence, explanation of pathophysiological mechanisms and role of various factors; urinary pH, uric acid, parathyroid hormone, citrate, oxalate, calcium and macromolecules; osteopontin, matrix Gla protein, kidney injury molecules, urinary prothrombin fragment-1, Tamm-Horsfall protein, inter-α-inhibitors, have been dis...
Preclinical animal research has greatly contributed and will continue to contribute in our unders... more Preclinical animal research has greatly contributed and will continue to contribute in our understanding of various disease states and provided methods for more understanding of disease states and designs to test novel pharmaco-therapeutic interventions against these diseases. For urolithiasis, scientists have developed numerous in vitro and in vivo models that attempt to replicate human urolithiasis. In this review, I have explained in vitro and in vivo models that are more common, affordable, and easy to replicate. In the in vitro models, I have focused on the CaOx crystallization models and in the in vivo models, hyperoxaluric rat model has been explained along with other available option such as Knockout (KO) mice and fly models. Each model has been explained stepwise along with its pros and cons.
Salivary gland inflammation is a hallmark of Sjögren's syndrome (SS), a common autoimmune dis... more Salivary gland inflammation is a hallmark of Sjögren's syndrome (SS), a common autoimmune disease characterized by lymphocytic infiltration of the salivary gland and loss of saliva secretion, predominantly in women. The P2X7 receptor (P2X7R) is an ATP-gated nonselective cation channel that induces inflammatory responses in cells and tissues, including salivary gland epithelium. In immune cells, P2X7R activation induces the production of proinflammatory cytokines, including IL-1β and IL-18, by inducing the oligomerization of the multiprotein complex NLRP3-type inflammasome. Here, our results show that in primary mouse submandibular gland (SMG) epithelial cells, P2X7R activation also induces the assembly of the NLRP3 inflammasome and the maturation and release of IL-1β, a response that is absent in SMG cells isolated from mice deficient in P2X7Rs (P2X7R(-/-)). P2X7R-mediated IL-1β release in SMG epithelial cells is dependent on transmembrane Na(+) and/or K(+) flux and the activati...
International Journal of Environmental Research and Public Health
The world is still in need of an effective therapy to treat coronavirus disease-19 (COVID-19). Th... more The world is still in need of an effective therapy to treat coronavirus disease-19 (COVID-19). This cross-sectional study was conducted on COVID-19 survivors in Saudi Arabia to investigate the influence of a healthy diet on the recovery time from COVID-19. A questionnaire was developed to assess participants’ dietary habits, based on the 2015 Dutch food-based dietary guidelines. A total of 738 COVID-19 survivors participated in the study, of whom 237 (32.1%) were hospitalized for COVID-19 treatment while 501 (76.9%) were not hospitalized, and 320 (43.4%) were females and 418 (56.6%) were males. Overall, no significant difference was noted in healthy diet score between males and females; however, this score was significantly lower for Saudis compared to non-Saudis. Among the non-hospitalized patients, eating a more healthy diet was associated with a shorter duration of recovery (p < 0.05) and was significantly affected by gender (15.8 ± 9.3 male vs. 12.1 ± 8.9 female; p < 0.001...
ISTFA 2021: Conference Proceedings from the 47th International Symposium for Testing and Failure Analysis
Semiconductor manufacturing has been outsourced to un-trusted regions due to globalization. The c... more Semiconductor manufacturing has been outsourced to un-trusted regions due to globalization. The complex multistep fabrication of micro-scale integrated circuits (ICs) and the tedious assembly of macro-scale Printed Circuit Boards (PCBs) are vulnerable to malicious attacks from design to final delivery. PCBs provide the functional connections of Integrated Circuits (ICs), sensors, power supplies, etc. of many critical electronic systems for consumers, corporations, and governments. The feature sizes of PCB signal traces in 2D and vias in 3D are an order of magnitude larger than IC devices, and are thereby more vulnerable to non-destructive attacks such as X-ray or probing. Active and passive countermeasures have been successfully developed for IC devices, however PCBs devices are difficult to wholly secure from all attacks. Passive countermeasures for X-ray attacks using high-z materials to block and scatter X-rays are effective, but there is a lack of active and passive countermeasu...
Black seeds (Nigella sativa) owe an important place due to its more demand as a food as well as m... more Black seeds (Nigella sativa) owe an important place due to its more demand as a food as well as medicine. A lack of information does exist regarding the quality and safety for market-available food-grade samples of black seed (BS). The aim of this study is to investigate the quality and standardize the BS samples according to world health organization (WHO) guidelines of instrumental analysis and pharmacological activities. Instrumental analysis was performed with the help of ASE (accelerated solvent extraction), IR (infrared spectroscopy), UHPLC (ultra-high-performance liquid chromatography) and NMR (nuclear magnetic resonance spectroscopy) whereas ash values and chemical tests were applied for physicochemical analysis. DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and cytotoxicity assay were performed as well. A high extract yield (g) with recovery of 4.4 ± 7.7 (22%) for Pakistani, 3.3 ± 4.7 (16.5%) for Indian and 3.02 ± 10...
Journal of the Pediatric Infectious Diseases Society
We describe the presentation and treatment of a patient who developed ongoing fever and diagnosed... more We describe the presentation and treatment of a patient who developed ongoing fever and diagnosed with disseminated toxoplasmosis post-hematopoietic stem cell transplantation. He was initially treated with trimethoprim-sulfamethoxazole (TMP-SMX) and there was dramatic improvement in his fever curve. He successfully completed a modified course of therapy.
In this study, we analyze the properties of boron isotope (B)-rich powders from three different s... more In this study, we analyze the properties of boron isotope (B)-rich powders from three different sources, that is, American, Cambridge, and Pavezyum, to fabricate the bulk MgB superconductors and evaluate their superconducting properties. While B-rich powder is an essential precursor to fabricate MgB superconductors for fusion magnet applications, the properties of the B powder turned out to be critical to determine the quality of the final superconducting product. Therefore, appropriate control of processing conditions is needed to comply with the requirements of the nuclear fusion application. Analysis of the B isotope ratio by accelerator mass spectroscopy and neutron transmission revealed that all three types of powder are enriched with B to better than 99 at % quality. In addition, Pavezyum's B shows the lowest crystallinity and smallest crystalline domain size as evidenced by the high-resolution X-ray diffractometer and scanning electron microscopy. The chemical states of the boron isotope investigated with near edge X-ray absorption fine structure spectroscopy and X-ray photoemission spectroscopy also reveals that Pavezyum boron has amorphous structure. MgB bulks and multi-filamentary (12-filament) wires have been manufactured, sintered at different temperatures and characterized via the transport critical current density. The wire with Pavezyum B shows three times higher current carrying capacity at a particular magnetic field compared to the wire using Cambridge B and hence, Pavezyum B boron has the potential for manufacturing fusion grade MgB based magnets. The results of this study demonstrated that Boron powders with higher purity, smaller grain size and lower crystallinity are critical for improving the superconducting and electronic properties of MgB samples fabricated from the powder. Thus, the low-neutron-activation MgB is possibly an affordable and technically viable candidate to replace NbTi superconductors in the low field poloidal field and correction coils for the next-generation fusion reactors.
Abstract Nickel oxide has tremendous applications in the field of biomedicine. In this study, NiO... more Abstract Nickel oxide has tremendous applications in the field of biomedicine. In this study, NiO nanoparticles were synthesized with different Bi contents (NiO@Bi; 0.0–7.5 wt%), and multifunctional usages were investigated. Structural confirmation was conducted through XRD and Raman studies, which revealed a monophasic cubic system. With increasing Bi content, broadening of the XRD and Raman peaks were observed, indicating a reduction in particle size. The crystallite size was found to be in the range of 10–26 nm. The decrease in particle size was confirmed through dynamic light scattering measurement. The homogeneous distribution of all elements and the presence of Bi were detected by an EDX/SEM e-mapping study. Field emission electron microscopy confirmed the formation of spherical shape nanoparticles. The grain size was reduced from 30 nm to 10 nm with Bi content, in accordance with XRD and Raman results. The Kubelka-Munk method was employed to determine the effect of Bi content on the optical band gap of NiO. The energy gap was reduced with Bi content in the range of 3.32–3.50 eV. Antimicrobial and in vitro cytotoxic characteristics of the prepared NPs were also studied. The results revealed that all NiO@Bi NPs had negligible antimicrobial activity and no cytotoxic effects on both normal and activated splenic cells. The in vivo acute cytotoxicity study indicated no cytotoxic effects on liver and kidney functions. The prepared NiO@Bi NPs were implanted in living organisms without hepatic/renal toxicity, demonstrating excellent biocompatibility, cell viability, and superior quality of nanocrystals, suggesting that the prepared NPs are ideal candidates for antibacterial and biomedical applications.
A mobile ad hoc network (MANET) may be a self-configured, infrastructure-less network of mobile n... more A mobile ad hoc network (MANET) may be a self-configured, infrastructure-less network of mobile nodes that move independently. Owing to this movement, links can change often and can require special routing techniques to handle this. Every node acts as an intermediate router to receive and transmit packets. in this paper, the impact of varying transmission range on different propagation model and queue model on 3 routing protocols specifically AODV, DSR and DYMO is analyzed. The simulations were done on Qualnet. The significant metrics used for comparative analysis are- throughput, end-to-end delay and average jitter. The nodes of designed scenario communicate all the way through constant bit rate (CBR) application traffic. It is found that AODV is best performer under CBR traffic for MANET nodes operated through Okumura Propagation Model with queue technique as well as DYMO performs well in free space propagation model using queuing technique. This paper also summarize as the node d...
Introduction: Knowledge and attitudes towards proper antibiotic usage among students in medical a... more Introduction: Knowledge and attitudes towards proper antibiotic usage among students in medical and other health allied fields play a vital role in limiting the pandemic of antibiotic resistance. This study aimed to assess knowledge and attitudes toward antibiotic usage among pre-professional students at King Saud bin Abdulaziz University for Health Sciences on Jeddah Campus, Saudi Arabia. Methods: A self-administered cross-sectional survey of 347 first year students was conducted at the College of Science and Health Professions, King Saud bin Abdulaziz University for Health Sciences using a validated questionnaire. Results: Nearly 63% of the students had a moderate level of knowledge. Two third of the students (69.7%) correctly knew that antibiotics are indicated for the treatment of bacterial infections. However, about 36% of the students incorrectly thought that antibiotics are also used to treat viral infections, while 28.5% were not sure. Only 38.8% of the students were aware o...
Colloids and Surfaces A: Physicochemical and Engineering Aspects
Abstract Zinc oxide is well-known material and used in several applications. We have synthesized ... more Abstract Zinc oxide is well-known material and used in several applications. We have synthesized the good quality ZnO nanoparticles with different concentrations of Strontium (Sr) doping for photocatalytic applications. The elemental composition and homogeneous distribution of Sr doping in ZnO was investigated through EDX/SEM mapping. The morphology of synthesize products was studied through FE-SEM and grain size was estimated. X-ray diffraction (XRD) and FT-Raman spectroscopy analyses approves the single phase and purity of synthesized Sr:ZnO NPs as no additional peak in XRD and Raman was seen. The size of crystallites was estimated using Scherrer equation and noticed to be reduced from 24 to 16 nm with rising the Sr concentration. The energy gap was estimated using Kubelka-Munk function and noticed in range from 3.25–3.27 eV with Sr concentration. The photoluminescence spectra were recorded for all Sr:ZnO NPs at λexc =350 nm. The photocatalytic activity of Sr:ZnO NPs samples was investigation by decolourization of methylene blue (MB) dye under irradiation of black-light in an aqueous solution at ambient conditions. A remarkable improvement in photocatalytic activity was obtained for the entire prepared Sr:ZnO samples compared to that of neat ZnO. Such improvement in photocatalytic activity can be attributed to the effective photogenerated charges separating, in addition to the good adsorption of MB dye molecules over Sr:ZnO NPs surface.
Silicon carbide (SiC), owing to its extraordinary chemical stability and refractory properties, i... more Silicon carbide (SiC), owing to its extraordinary chemical stability and refractory properties, is widely used in the manufacturing industry. Despite the semiconducting nature and morphology-tuned band gap, its efficacy as photocatalysts has not been thoroughly investigated. The current study reports the synthesis, characterization and the evaluation of the capability of silicon carbide for hydrogen generation from water splitting. The optical characterization of the as-synthesized powder exposed the formation of multi-wavelength absorbing entities in synthetic process. The structural analysis by XRD and the fine microstructure analysis by HRTEM revealed the cubic 3C-SiC (β-SiC) and hexagonal α-polymorphs (2H-SiC and 6H-SiC) as major and minor phases, respectively. The Mott–Schottky analysis verified the n-type nature of the material with the flat band potential of − 0.7 V. In the electrochemical evaluation, the sharp increase in the peak currents in various potential ranges, under illumination, revealed the plausible potential of the material for the oxidation of water and generation of hydrogen. The generation of hydrogen and oxygen, as a consequence of water splitting in the actual photocatalytic experiments, was observed and measured. A significant increase in the yield of hydrogen was noticed in the presence of methanol as h+ scavenger, whereas a retarding effect was offered by the Fe3+ entities that served as e− scavengers. The combined effect of both methanol and Fe3+ ions in the photocatalytic process was also investigated. Besides hydrogen gas, the other evolved gasses such as methane and carbon monoxide were also measured to estimate the mechanism of the process.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Tb-doped Y2O3 microspheres (MSs) were prepared via a homogeneous thermal degradation process at a... more Tb-doped Y2O3 microspheres (MSs) were prepared via a homogeneous thermal degradation process at a low temperature and then coated with a nanosilica shell (Y2O3:Tb@SiO2) using a sol-gel process. The core MSs were highly crystalline and spherical with a porous surface, single cubic phase, and particle size of 100-250 nm. Transmission electron microscopy (TEM) images clearly showed the spherical shape of the as-prepared core MSs, which were fully covered with a thick and mesoporous nanosilica shell. Fourier transform infrared (FTIR) spectra displayed the well-resolved infrared absorption peaks of silica (SiO, SiOSi, etc.), confirming the presence of the silica surface coating. The core MSs retained their spherical shape even after heat treatment and subsequent silica surface coating. It was observed that the core/shell MSs are easily dispersible in aqueous media and form a semi-transparent colloidal solution. Ultraviolet/visible and zeta potential studies were tested to prove the changes in the surface chemistry of the as-designed core/shell MSs and compare with their core counterpart. The growth of the amorphous silica shell not only increased the particle size but also enhanced remarkably the solubility and colloidal stability of the MSs in aqueous media. The strongest emission lines originating from the characteristic intra-shell 4f-4f electronic transitions of Tb ions were quenched after silica layer deposition, but the MSs still showed strong green (5D4 → 7F5 at 530-560 nm as most dominant) emission efficiency, which indicates great potential in fluorescent bio-probes. The emission intensity is discussed in relation to the quenching mechanism induced by surface silanol (Si-OH) groups, particle size, and surface charge.
International urology and nephrology, Jan 22, 2018
The formation of urinary stone, urolithiasis, is one the oldest known disease affecting human thr... more The formation of urinary stone, urolithiasis, is one the oldest known disease affecting human throughout different civilizations and times. The exact pathophysiological mechanism of urolithiasis is not yet clear, as these calculi are of various types and too complex for simple understanding. A single theory cannot explain its formation; therefore, different theories are presented in various times for its explanation like free particle, fixed particle, Randall's plaque theory. In addition, various factors and components are identified that play an important role in the formation of these urinary calculi. In this review, composition of kidney stones, its prevalence/incidence, explanation of pathophysiological mechanisms and role of various factors; urinary pH, uric acid, parathyroid hormone, citrate, oxalate, calcium and macromolecules; osteopontin, matrix Gla protein, kidney injury molecules, urinary prothrombin fragment-1, Tamm-Horsfall protein, inter-α-inhibitors, have been dis...
Preclinical animal research has greatly contributed and will continue to contribute in our unders... more Preclinical animal research has greatly contributed and will continue to contribute in our understanding of various disease states and provided methods for more understanding of disease states and designs to test novel pharmaco-therapeutic interventions against these diseases. For urolithiasis, scientists have developed numerous in vitro and in vivo models that attempt to replicate human urolithiasis. In this review, I have explained in vitro and in vivo models that are more common, affordable, and easy to replicate. In the in vitro models, I have focused on the CaOx crystallization models and in the in vivo models, hyperoxaluric rat model has been explained along with other available option such as Knockout (KO) mice and fly models. Each model has been explained stepwise along with its pros and cons.
Salivary gland inflammation is a hallmark of Sjögren's syndrome (SS), a common autoimmune dis... more Salivary gland inflammation is a hallmark of Sjögren's syndrome (SS), a common autoimmune disease characterized by lymphocytic infiltration of the salivary gland and loss of saliva secretion, predominantly in women. The P2X7 receptor (P2X7R) is an ATP-gated nonselective cation channel that induces inflammatory responses in cells and tissues, including salivary gland epithelium. In immune cells, P2X7R activation induces the production of proinflammatory cytokines, including IL-1β and IL-18, by inducing the oligomerization of the multiprotein complex NLRP3-type inflammasome. Here, our results show that in primary mouse submandibular gland (SMG) epithelial cells, P2X7R activation also induces the assembly of the NLRP3 inflammasome and the maturation and release of IL-1β, a response that is absent in SMG cells isolated from mice deficient in P2X7Rs (P2X7R(-/-)). P2X7R-mediated IL-1β release in SMG epithelial cells is dependent on transmembrane Na(+) and/or K(+) flux and the activati...
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