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41.
Muhammad Rabeel Sofia Javed Ramsha Khan Muhammad Aftab Akram Shania Rehman Deok-kee Kim Muhammad Farooq Khan 《Materials》2022,15(9)
Herein, we synthesized the zinc oxide (ZnO) thin films (TFs) deposited on glass substrates via spray pyrolysis (SP) to prepare self-cleaning glass. Various process parameters were used to optimize photocatalytic performance. Substrates were coated at room temperature (RT) and 250 °C with a 1 mL or 2 mL ZnO solution while maintaining a distance from the spray gun to the substrate of 20 cm or 30 cm. Several characterization techniques, i.e., XRD, SEM, AFM, and UV–Vis were used to determine the structural, morphological, and optical characteristics of the prepared samples. The wettability of the samples was evaluated using contact angle measurements. As ZnO is hydrophilic in nature, the RT deposited samples showed a hydrophilic character, whereas the ZnO TFs deposited at 250 °C demonstrated a hydrophobic character. The XRD results showed a higher degree of crystallinity for samples deposited on heated substrates. Because of this higher crystallinity, the surface energy decreased, and the contact angle increased. Moreover, by using 2 mL solution, better surface coverage and roughness were obtained for the ZnO TFs. However, by exploiting the distance of the spray to the samples size distribution and surface coverage can be controlled, the samples deposited at 30 mL showed a uniform particle size distribution from 30–40 nm. In addition, the photoactivity of the samples was tested by the degradation of rhodamine B dye. Substrates prepared with a 2 mL solution sprayed at 20 cm showed higher dye degradation than other samples, which can play a vital role in self-cleaning. Hence, by changing the said parameters, the ZnO thin film properties on glass substrates were optimized for self-cleaning diversity. 相似文献
42.
Izaz Ahmad Mudasir Iqbal Asim Abbas Yasir Irfan Badrashi Arshad Jamal Shahid Ullah Ahmed M. Yosri Moustafa Hamad 《Materials》2022,15(9)
Steel fibers are widely extracted from scrap tyres, causing environmental concerns. This paper presents the use of steel fibers in variable proportions extracted from scrap tyres. The enhancement of the confinement was envisaged through the addition of steel fibers obtained from scrap tyres. The study included an experimental program for the development of constitutive material models for ordinary Portland cement (OPC) concrete and concrete with added steel fibers. A mix design was carried out for OPC, targeting a compressive strength of 3000 psi. Steel fibers were added to OPC in ratios of 1.0% to 3.0%, with an increment of 0.5%. Concrete columns, with cross-sectional dimensions of 6 × 6 inches and a length of 30 inches, were cast with both OPC and fiber-reinforced concrete. The column confinement was evaluated with a different spacing of ties (3- and 4-inch center-to-center). Compression tests on the concrete columns indicate that the addition of steel fibers to a concrete matrix results in an appreciable increase in strength and ductility. Overall, increasing the percentage of steel fibers increased the compression strength and the ductility of concrete. The maximum strain in the concrete containing 2.5% steel fibers increased by 285% as compared to the concrete containing 1% of steel fibers. An optimum percentage of 2.5% steel fibers added to the concrete resulted in a 39% increase in compressive strength, accompanied by a significant improvement in ductility. The optimum content of steel fibers, when used in confined columns, showed that confined compression strength increased with the addition of steel fibers. However, it is recommended that additional columns on the basis of the optimum steel fiber content shall be tested to evaluate their effectiveness in reducing the stirrup spacing. 相似文献
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44.
G Patil MI Khan DK Patel S Sultana R Prasad I Ahmad 《Environmental toxicology and pharmacology》2012,34(2):436-445
Dolomite is a natural mineral of great industrial importance and used worldwide, thus millions of workers are at risk of occupational exposure. Its toxicity is however, meagerly documented. In the present investigation, a dolomite powder obtained from its milling unit was analyzed by some standard methods namely, optical microscopy, transmission electron microscopy and dynamic light scattering. Results showed that dolomite powder contained particles of different shapes and size both microparticles (MPs) and nanoparticles (NPs), suggesting potential occupational exposure of these particles. An attempt was therefore, made to investigate dolomite toxicity in a particle size-dependent manner in human lung epithelial cells A(549). The comparative toxicity evaluation of MPs and NPs was carried out by assessing their effects on cell viability, membrane damage, glutathione, reactive oxygen species (ROS), lipid peroxidation (LPO), micronucleus (MN) and proinflammatory cytokines, namely tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). These markers of cytotoxicity, genotoxicity and inflammation were assayed in cells exposed to MPs and NPs in a dose-and time-dependent manner. Invariably, their toxic effects were dose-and time-dependent while NPs in general were significantly more toxic. Notably, NPs caused oxidative stress, genotoxicity and inflammatory responses, as seen by significant induction of ROS, LPO, MN, TNF-α, IL-1β and IL-6. Thus, the study tends to suggest that separate health safety standards would be required for micrometer and nanometer scale particles of dolomite. 相似文献
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47.
M.S. Iqbal G. Vashisht R. McMenemin P. Atherton F. McDonald T. Simmons A. Bradshaw J. Kovarik H. Turnbull L. Dodd P. Mulvenna A. Greystoke 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(2):e1-e10
Aims
Concomitant chemoradiation is the standard of care in patients with inoperable non-small cell lung cancer. The purpose of this study was to analyse the survival outcome and toxicity data of using hypofractionated chemoradiation.Materials and methods
One hundred patients were treated from June 2011 to November 2016. Treatment consisted of 55 Gy in 20 daily fractions concurrently with split-dose cisplatin vinorelbine chemotherapy over 4 weeks followed by two cycles of cisplatin vinorelbine only. Survival was estimated using Kaplan–Meier and Cox regression was carried out for known prognostic factors. A systematic search of literature was conducted using Medline, Embase and Cochrane databases and relevant references included.Results
In total, 97% of patients completed radiotherapy and 73% of patients completed all four cycles of chemotherapy. One patient died of a cardiac event during consolidative chemotherapy. There were two cases of grade 4 toxicities (one sepsis, one renal impairment). Grade 3 toxicities included nausea/vomiting (17%), oesophagitis (15%), infection with neutropenia (12%) and pneumonitis (4%). Clinical benefit was seen in 86%. Two-year progression-free survival and overall survival rates were 49% and 58%, respectively. The median progression-free survival and overall survival were 23.4 and 43.4 months, respectively. The only significant prognostic factor was the number of chemotherapy cycles received (P = 0.02). The systematic review identified 13 relevant studies; a variety of regimens were assessed with variable reporting of outcomes and toxicity but with overall an improvement in survival over time.Conclusion
Our experience compared with the original phase II trial showed improved treatment completion rates and survival with acceptable morbidity. With appropriate patient selection this regimen is an effective treatment option for locally advanced non-small cell lung cancer. This study helps to benchmark efficacy and toxicity rates while considering the addition of new agents to hypofractionated concurrent chemoradiotherapy. The agreement of a standard regimen for assessment in future trials would be beneficial. 相似文献48.
Nicholas Murphy Nithya Ramakrishnan Bylinda Vo-Le Brittany Vo-Le Mark A. Smith Tabish Iqbal Alan C. Swann Sanjay J. Mathew Marijn Lijffijt 《Neuropsychopharmacology》2021,46(4):820
The kynurenine pathway (KP) is a strategic metabolic system that combines regulation of neuronal excitability via glutamate receptor function and neuroinflammation via other KP metabolites. This pathway has great promise in treatment of depression and suicidality. The KP modulator AV-101 (4-chlorokynurenine, 4-Cl-KYN), an oral prodrug of 7-chlorokynurenic acid (7-Cl-KYNA), an N-methyl-d-aspartate receptor (NMDAR) glycine site antagonist, and of 4-chloro-3-hydroxyanthranilic acid (4-Cl-3-HAA), a suppressor of NMDAR agonist quinolinic acid (QUIN), is a promising potential antidepressant that targets glutamate functioning via the KP. However, a recent placebo-controlled clinical trial of AV-101 in depression found negative results. This raises the question of whether AV-101 can penetrate the brain and engage the NMDAR and KP effectively. To address this problem, ten healthy US military veterans (mean age = 32.6 years ± 6.11; 1 female) completed a phase-1 randomized, double-blind, placebo-controlled, crossover study to examine dose-related effects of AV-101 (720 and 1440 mg) on NMDAR engagement measured by γ-frequency band auditory steady-state response (40 Hz ASSR) and resting EEG. Linear mixed models revealed that 1440 mg AV-101, but not 720 mg, increased 40 Hz ASSR and 40 Hz ASSR γ-inter-trial phase coherence relative to placebo. AV-101 also increased 4-Cl-KYN, 7-Cl-KYNA, 4-Cl-3-HAA, 3-HAA, and KYNA in a dose-dependent manner, without affecting KYN and QUIN. AV-101 was safe and well tolerated. These results corroborate brain target engagement of 1440 mg AV-101 in humans, consistent with blockade of interneuronal NMDAR blockade. Future studies should test higher doses of AV-101 in depression. Suicidal behavior, which has been associated with high QUIN and low KYNA, is also a potential target for AV-101.Subject terms: Biomarkers, Neurophysiology, Neuroscience 相似文献
49.
Fleischmann RM Stern RL Iqbal I 《Modern rheumatology / the Japan Rheumatism Association》2005,15(3):153-162
Recent advances in the understanding of the pathophysiology, aggressive treatment, and early detection of rheumatoid arthritis (RA) have changed the clinical, pathologic, and functional outcomes in patients with RA. Early aggressive treatment of RA has now become the norm in clinical practice rather than the use of the traditional pyramid approach of the last half of the twentieth century. Early treatment with monotherapy of traditional disease-modifying antirheumatic drugs (DMARDs) or biologics, combination traditional DMARD therapy and, especially, combination of biologic therapy and methotrexate, have revolutionized the treatment of RA, producing significant improvement in clinical, radiographic, and functional outcomes not seen previously. For the individual patient, we still cannot determine which medication or combination of medications will give the most complete response. There have been a number of recent, well-designed clinical trials that have tried to answer this question. Herein we review the evidence-based medicine that addresses these issues. 相似文献
50.
Hira PR Assad RM Okasha G Al-Ali FM Iqbal J Mutawali KE Disney RH Hall MJ 《The American journal of tropical medicine and hygiene》2004,70(4):386-389
Myiasis, the invasion of live human tissue by larvae of Diptera, is reported in the nasopharynx and a leg wound in two patients who were hospitalized for more than 72 hours in Mubarak Al-Kabeer Teaching Hospital in Kuwait City, Kuwait. On the fourth and fifth days after a 10-year-old Kuwaiti boy was admitted to the hospital intensive care unit in a bloodied and comatose state following a traffic accident, 'worms' that came out of his nostrils were fixed, cleared, and identified as second and third instar of Lucilia sericata (Diptera: Calliphoridae). After 14 days, 'worms' were seen in the original dressing of a 35-year-old Iranian man admitted to the Orthopedic Unit of the hospital with multiple lacerations and fractures. The larvae, in various stages of development, were identified as those of Megaselia scalaris (Diptera: Phoridae). Since the presence of larvae in both patients was recorded after a stay of at least 3-4 days in the hospital, by definition, these infestations are considered nosocomial. 相似文献