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EA Ismail IS Shabani M Badawi H Sanaa S Madi A Al-Tawari H Nadi M Zaki Q Al-saleh 《Canadian Metallurgical Quarterly》1998,13(10):488-492
We studied Guillain-Barré syndrome, affecting children 12 years old or less, throughout Kuwait, in the period between January 1, 1992, and March 31, 1997. Nineteen children had the diagnostic criteria of Guillain-Barré syndrome, with an overall annual incidence rate of 0.95/100,000 population at risk. Female patients outnumbered male patients with a sex ratio of 1.4:1. There was a clustering of cases in winter and spring and in the year 1996. The disease symptoms were relatively severe in our patients because only 16% (3 of 19) of them were able to walk at the height of their illness, whereas the rest were bed or chair bound or needed assisted ventilation. Two patients had the electrodiagnostic features of axonal neuropathy and both had residual deficits on follow-up, whereas the rest recovered fully. All the patients received intravenous immunoglobulin. The mean time to walk unaided was 23.5 days (range, 2-84 days) after intravenous immunoglobulin and excluding the two patients with axonal neuropathy, and full recovery was achieved in a mean time of 103 days (range, 30-300 days). Contrary to previous studies, we found no correlation between oral polio vaccine administration and Guillain-Barré syndrome in 2 successive years (1995 and 1996) during a nationwide campaign targeting children less than 5 years old. 相似文献
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Mahdiar Ghadiry Asrulnizam Bin Abd Manaf Mahdieh Nadi Meisam Rahmani M.T. Ahmadi 《Microelectronics Reliability》2012,52(7):1396-1400
A semi-analytical model for impact ionization coefficient of graphene nanoribbon (GNR) is presented. The model is derived by calculating probability of electrons reaching ionization threshold energy Et and the distance travelled by electron gaining Et. In addition, ionization threshold energy is semi-analytically modelled for GNR. During modelling, we justify our assumptions using analytical modelling and comparison with simulation. Furthermore, it is shown that conventional silicon models are not valid for calculation of ionization coefficient of GNR. Finally, the profile of ionization is presented using the proposed models and the results are compared with that of silicon. 相似文献
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Guusje van Schaick Nadi el Hajjouti Simone Nicolardi Joost den Hartog Romana Jansen Rob van der Hoeven Wim Bijleveld Nicolas Abello Manfred Wuhrer Maurien M. A. Olsthoorn Elena Domínguez-Vega 《International journal of molecular sciences》2022,23(3)
Xylanases are of great value in various industries, including paper, food, and biorefinery. Due to their biotechnological production, these enzymes can contain a variety of post-translational modifications, which may have a profound effect on protein function. Understanding the structure–function relationship can guide the development of products with optimal performance. We have developed a workflow for the structural and functional characterization of an endo-1,4-β-xylanase (ENDO-I) produced by Aspergillus niger with and without applying thermal stress. This workflow relies on orthogonal native separation techniques to resolve proteoforms. Mass spectrometry and activity assays of separated proteoforms permitted the establishment of structure–function relationships. The separation conditions were focus on balancing efficient separation and protein functionality. We employed size exclusion chromatography (SEC) to separate ENDO-I from other co-expressed proteins. Charge variants were investigated with ion exchange chromatography (IEX) and revealed the presence of low abundant glycated variants in the temperature-stressed material. To obtain better insights into the effect on glycation on function, we enriched for these species using boronate affinity chromatography (BAC). The activity measurements showed lower activity of glycated species compared to the non-modified enzyme. Altogether, this workflow allowed in-depth structural and functional characterization of ENDO-I proteoforms. 相似文献
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Mahdieh Namvar-Mahboub Ahsani Fatemeh Ansari Soudabeh 《Theoretical Foundations of Chemical Engineering》2020,54(5):940-948
Theoretical Foundations of Chemical Engineering - Effect of activating procedure on the physic-chemical properties and adsorption performance of activated carbon was investigated. For this,... 相似文献
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The development of technical textiles allows the introduction of new, interesting and original multi-functionalities in textiles through development of the architecture of fibres, yarns and fabrics, their morphology and surface functionalization without altering their physico-chemical proprieties. This issue of Textile Progress reports different techniques used to impart new functionalities to the surfaces of textiles during the last decade. Following a short, context-setting historical introduction, the preparatory processes which need to be applied to textile matrices to make them clean and ready for functionalization are examined prior to a comprehensive review of techniques and research related to the development of functional textiles ranging from the more-traditional techniques through to more-recent developments. The challenge now is to bring new performance features to bear whilst maintaining environmental sustainability, chemical toxicological acceptability, high performance and cost effectiveness. In this context, the review reports on developments in the use of polymerization, nanotechnologies, plasma treatment, electrospinning, microencapsulation and sol gel techniques to impart novel properties to a textile surface such as water-repellent, flame-retardant and antibacterial properties. 相似文献
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The oxidation of alcohols with tert-butylhydroperoxide (TBHP), in the presence of Mn2+ complexes immobilized in the pore channels of mesoporous hexagonal molecular sieves (HMS), were investigated. It was found that immobilized [Mn(bpy)2]2+/HMS is an efficient catalyst for the oxidation of alcohols such as benzyl alcohol, n-hexanol and cyclohexanol. The effects of reaction time, amount of Mn2+ in the catalyst, type of substrates and oxidants in this catalysis system were investigated. At optimum conditions, TBHP is more efficient oxidant with respect to H2O2. Following order has been observed for the percentage of conversions of alcohols: benzylic >1° >2°. 相似文献
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We present new chemical, crystallographic and electrical conductivity data concerning the title compounds. It is found that the
axis repeat distances of the bi-intercalation compounds (GBC) are almost identical to the sum of the interplanar distances of the associated binary compounds. The basal plane resistivity ρa decreases upon intercalation of the second halide into the stage two, binary host: ρa 5 ± 1 μΩ cm at 295 K and
for the GaCl3− and AlCl3-containing GBC. The
axis resistivity possesses a positive temperature coefficient for all compounds examined except the 4th stage FeCl3 GIC. The room temperature anisotropy is 106 for 1st and 4th stage GaCl3 GIC as for low stage AsF5 materials. Chemically determined values of the charge transfer are about twice as great as those evaluated from analysis of the C-C bond distances. 相似文献
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Mehdi Tarkhani Seyyed Abbas Mousavi Mahdieh Asadollahi Dariush Bastani Fatemeh Pourasad 《Polymer Engineering and Science》2023,63(3):986-1000
This study aims to investigate polysulfone (PSF) mixed matrix membranes (MMMs) properties containing zirconium-based and titanium-based metal–organic frameworks (MOFs). for hemodialysis application. The nanoparticles were synthesized, and the membranes were produced by the phase inversion method. Membrane characterization conducted by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), field emission Scanning electron microscope (FE-SEM), energy-dispersive x-ray analysis (EDX), transmission electron microscopy (TEM), x-ray diffraction (XRD), and atomic force microscopy (AFM) confirmed the presence of MOF nanoparticles. Also, the evaluation of the specific surface area of nanoparticles was done by BET. The water contact angle reduced from 64.4° to 51.2°, indicating the hydrophilicity improvement, enhancing the pure water flux from 46.8 L/m2h for the pristine membrane to 76.7 L/m2h for the pristine membrane M4. The total fouling resistance decreased from 30% to 21%, and the bovine serum albumin (BSA) adsorption of modified membranes was lower than that of the pristine membrane. Urea and creatinine were cleared significantly for modified ones, up to 82.6% and 72.1%, respectively, and all membranes showed BSA retention of more than 93%. A comparison between MMMs that contained UIO-66-NH2 and MIL-125-NH2 showed that the former had a better effect on the performance. M4 had better results, indicating high water flux, the lowest fouling resistance, high porosity, lower BSA adsorption, proper clearance for urea and creatinine, and 94.2% BSA retention. 相似文献