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251.
J Sunyer JM Antó J Sabrià J Roca F Morell R Rodríguez-Roisin MJ Rodrigo 《Canadian Metallurgical Quarterly》1995,95(3):699-706
BACKGROUND: General population studies have shown a relationship between total serum IgE levels and airway responsiveness, but this association has not been documented in patients with asthma. OBJECTIVE: The study assesses the cross-sectional relationship between IgE levels and airway responsiveness in 208 subjects who had had emergency department treatment for asthma at least 2 years earlier. METHODS: All participants completed a standardized respiratory questionnaire and underwent spirometry, allergy skin testing, and a dose-response methacholine challenge test. RESULTS: After adjusting for age and gender, the percentage of patients with asthma and airway responsiveness (provocative concentration causing a 20% fall in forced expiratory volume in 1 second [PC20] < or = 8 mg/ml) increased from 52% in the lower quintile of IgE to 72% in the upper quintile (p < 0.01). After adjusting for age, gender, baseline percent predicted forced expiratory volume in 1 second, and smoking, the association between IgE (both in quintiles and continuous) and PC20 appeared consistent and statistically significant (p < 0.01). This association was stronger in patients who were not given inhaled steroid (odds ratio for twice the concentration of IgE, 1.42; 95% confidence interval, 1.09 and 1.84), than in patients treated with inhaled steroid (odds ratio, 1.10; 95% confidence interval, 0.82 and 1.50). Eosinophilia and skin reactivity were associated with PC20 although to a lesser extent. CONCLUSION: These findings strengthen the role played by IgE in facilitating the development of bronchial responsiveness in patients with asthma. 相似文献
252.
The objectives of the work reported here is to review the performance of Jeddah Desalination plant during a period of 8 years of operation to provide insight into actual plant experience. Data have been extracted from plant monthly reports and maintenance orders. The analysis provided here is based on objective evaluations of operations data and experience and is directed towards assessment of problems that can be mitigated in new designs of MSF plants and recommendations for improvement or modifications of existing designs or procedures. 相似文献
253.
Mohammed A. H. Farouq Karina Kubiak-Ossowska Mohammed M. Al Qaraghuli Valerie A. Ferro Paul A. Mulheran 《International journal of molecular sciences》2022,23(9)
Staphylococcus protein A (SpA) is found in the cell wall of Staphylococcus aureus bacteria. Its ability to bind to the constant Fc regions of antibodies means it is useful for antibody extraction, and further integration with inorganic materials can lead to the development of diagnostics and therapeutics. We have investigated the adsorption of SpA on inorganic surface models such as experimentally relevant negatively charged silica, as well as positively charged and neutral surfaces, by use of fully atomistic molecular dynamics simulations. We have found that SpA, which is itself negatively charged at pH7, is able to adsorb on all our surface models. However, adsorption on charged surfaces is more specific in terms of protein orientation compared to a neutral Au (111) surface, while the protein structure is generally well maintained in all cases. The results indicate that SpA adsorption is optimal on the siloxide-rich silica surface, which is negative at pH7 since this keeps the Fc binding regions free to interact with other species in solution. Due to the dominant role of electrostatics, the results are transferable to other inorganic materials and pave the way for new diagnostic and therapeutic designs where SpA might be used to conjugate antibodies to nanoparticles. 相似文献
254.
Core–shell PVA/gelatin nanofibrous scaffolds using co‐solvent,aqueous electrospinning: Toward a green approach
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Mustafa Sengor Alp Ozgun Gulcan Corapcioglu Mehmet Ipekoglu Bora Garipcan Nuri Ersoy Sabri Altintas 《应用聚合物科学杂志》2018,135(32)
Electrospinning (ES) of gelatin often requires cytotoxic organic solvents or acidic environments, which deteriorate cell recognition sites. In this study, aqueous, non‐toxic, co‐solvent ES was performed to obtain core–shell poly(vinyl alcohol) (PVA)/gelatin nanofiber scaffolds. Effects of the core/shell feed rate ratio (FRR) were investigated on a morphological and mechanical basis. PVA:gelatin ratio of 1:4 was the limiting ratio for specific voltage and electrode distance parameters to obtain uniform fibers. Core–shell bead‐free structures were obtained at 8% PVA and gelatin aqueous solutions. A mean diameter of 280 nm was obtained for 1:1 FRR at 15 kV and 15 cm of electrode distance. Crosslinking resulted in slight improvement in tensile strengths and severe decrease in ductility. Fourier transform infrared spectra revealed retention and improvement of stable secondary structures of gelatin after ES. The scaffolds almost degraded more than 60% in 14 days. Based on the results, present scaffolds hold great promise as suitable candidates for biomedical applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46582. 相似文献
255.
Thermal,optical, and electrical characterization of thin film coated RTV 655 bilayer system
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Adhesion of thin films to hydrophobic elastomeric substrates is of particular interest in the area of flexible electronics and nano‐sensor technology. Here, nanometer‐thick Au films were deposited directly onto hydrophobic RTV 655 substrates by means of sputtering, thermal evaporation, and electroless techniques without an adhesion‐promoting layer. The bilayer system was exposed to repeat thermal cycling and changes to the surface morphology of the thin film were monitored electrically and optically. Buckle formation in the as‐deposited film was attributed to stress in the film and substrate stiffness rather than thermal coefficient mismatch between films. The Au‐RTV 655 interface was water tight and maintained a strong adhesion despite repeated thermal cycles. Sputtered and thermally evaporated carbon‐coated RTV 655 substrates were also studied in parallel for comparison. Periodic arrays of buckles formed in pre‐strained RTV 655 samples showed reproducibility in their optical properties demonstrating good adhesion between the two layers without an interfacial layer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41396. 相似文献
256.
Ling Wang Yuming Song Reena Gyanda Rajeev Sakhuja Nabin K. Meher Sureyya Hanci Kapil Gyanda Sindhu Mathai Firouzeh Sabri David A. Ciaramitaro Clifford D. Bedford Alan R. Katritzky Randolph S. Duran 《应用聚合物科学杂志》2010,117(5):2612-2621
Thirteen triazole polymers were prepared as potential rocket propellant binders by the reactions of various diacetylenes and diazides. The reaction of E300 dipropiolate ( 1 ) with diazide ( 2 ) obtained from tetraethylene glycol was selected to study the effects of concentration of the tetraacetylene functionalized crosslinker ( 3 ) on the mechanical properties of resulting triazole polymers. The modulus of the polymers increased, whereas the strain (% elongation at failure) decreased with increasing percentage of crosslinker. The resulting triazole polymers also showed that the desired mechanical properties could be obtained by adjusting the crosslinker concentration during the polymerization. Addition of 43 wt % aluminum filler did not significantly affect the strain. The modulus of these triazole polymers was comparable with typical polyurethane elastomeric matrices for rocket propellants. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
257.
Emad Ali Mohamed K. Hadj-Kali Sarwono Mulyono Inas Alnashef Anis Fakeeha Farouq Mjalli Adeeb Hayyan 《Chemical Engineering Research and Design》2014
Carbon dioxide capture and sequestration is drawing increasing attention as a potential method for controlling greenhouse gas emissions. Low cost ionic liquid analogues, namely, deep eutectic solvents (DESs), have attracted more attention for use in a diversity of applications. DESs exhibit many favourable properties, such as availability, non-toxicity, biodegradability, recyclability, non-flammability, and low price. 相似文献
258.
Mustafa Ismael Salman Ali Mohammed Mansoor Hamid Abdulla Jalab Aznul Qalid Md. Sabri Rodina Ahmed 《Wireless Personal Communications》2018,98(1):189-211
A green cellular technology is proposed to optimize the energy and spectrum resources. Such optimization will require perfect channel state information at the transmitting base station. However, reporting the channel status of the entire bandwidth requires huge undesirable feedback overhead. Therefore, the aim of this paper is to optimize the energy and bandwidth resources while maintaining quality-of-service at the downlink when a partial feedback is considered. In this paper, a modified downlink scheduler based on a Packet Prediction Mechanism (PPM) is conducted at the eNodeB to optimize the energy and spectrum resources. On the user equipment side, a partial channel feedback scheme based on an adaptive feedback threshold is developed. A primary concern of this feedback scheme is to reduce the uplink signaling overhead without a substantial loss in downlink performances. Finally, the downlink packet scheduling and the partial feedback are jointly evaluated to further enhance the system performance. Based on a system-level simulation results, the proposed energy-efficient scheduling with partial feedback has achieved an improvement in EE of up to 79% compared to the PPM scheduler. Besides, it minimizes the degradation caused by the partial channel quality indicator feedback. Thus, the proposed two-sided algorithm gives the best tradeoff between uplink and downlink performances. 相似文献