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91.
M. M. Shehata S. I. Radwan S. Abdel Samad M. Al-Abyad H. El-Khabeary 《Materialwissenschaft und Werkstofftechnik》2023,54(10):1196-1212
Gelatin was doped with 1 %, 3 %, 5 % and 10 % cadmium sulfide nanoparticles in weight concentrations forming the gelatin-cadmium sulfide nanocomposites and irradiated by various electron beam doses equals 50 kGy, 75 kGy, 100 kGy, and 150 kGy using 3 MeV – 3 mA electron accelerator. The applied alternating current electrical field frequency ranging from 70 Hz to 5 MHz is what caused the fluctuation in dielectric properties and alternating current electrical conductivity of these nanocomposites. The results showed that the films of 1 %, 3 %, 5 %, and 10 % for blank (nanocomposite film without electron beam irradiation) nanocomposites had the highest dielectric parameters (έ, ϵ′′, tan δ) at 0.5 kHz with values of (0.696, 0.0233, 0.034), (0.533, 0.0114, 0.0215), (0.402, 0.001196, 0.003), and (0.459, 0.00418, 0.0091), respectively. However, the lowest dielectric parameters were (0.645, 0.00618, 0.0066), (0.523, 0.00165, 0.0215), (0.417, 0.00035, 0.0008), and (0.455, 0.00066, 0.0015) at 5 MHz, respectively. The highest conductivity values for blank nanocomposites of 1 %, 3 %, 5 %, and 10 % were 1.79×10−4 S/m, 1.45×10−4 S/m, 1.16×10−4 S/m, 1.27×10−4 S/m at 5 MHz, and the lowest values were 1.92×10−8 S/m, 1.49×10−8 S/m, 1.13×10−8 S/m, 1.26×10−8 S/m at 0.5 kHz, respectively. For irradiated nanocomposites at 5 MHz, the dielectric constant order for 1 % was 100 kGy, 150 kGy, 50 kGy, and 75 kGy with values 0.63, 0.537, 0.532, and 0.523, respectively. For 10 % weight concentration, the order was 50 kGy, 100 kGy, 150 kGy, and 75 kGy with values 0.515, 0.477, 0.47, and 0.437, respectively. Otherwise the dielectric constant order for 3 % and 5 % was 100 kGy, 75 kGy, 150 kGy, and 50 kGy. The highest dielectric properties and conductivity values for blank and irradiated nanocomposites were observed at 100 kGy for 1 %, 3 %, and 5 %. 相似文献
92.
Milena Jankovic Ivana Novakovic Phepy Gamil Anwar Dawod Ayman Gamil Anwar Dawod Aleksandra Drinic Fayda I. Abdel Motaleb Sinisa Ducic Dejan Nikolic 《International journal of molecular sciences》2021,22(18)
Amyotrophic Lateral Sclerosis (ALS), neurodegenerative motor neuron disorder is characterized as multisystem disease with important contribution of genetic factors. The etiopahogenesis of ALS is not fully elucidate, but the dominant theory at present relates to RNA processing, as well as protein aggregation and miss-folding, oxidative stress, glutamate excitotoxicity, inflammation and epigenetic dysregulation. Additionally, as mitochondria plays a leading role in cellular homeostasis maintenance, a rising amount of evidence indicates mitochondrial dysfunction as a substantial contributor to disease onset and progression. The aim of this review is to summarize most relevant findings that link genetic factors in ALS pathogenesis with different mechanisms with mitochondrial involvement (respiratory chain, OXPHOS control, calcium buffering, axonal transport, inflammation, mitophagy, etc.). We highlight the importance of a widening perspective for better understanding overlapping pathophysiological pathways in ALS and neurodegeneration in general. Finally, current and potentially novel therapies, especially gene specific therapies, targeting mitochondrial dysfunction are discussed briefly. 相似文献
93.
Immune and Anticancer Responses Elicited by Fully Synthetic Aberrantly Glycosylated MUC1 Tripartite Vaccines Modified by a TLR2 or TLR9 Agonist
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Dr. Abu‐Baker M. Abdel‐Aal Dr. Vani Lakshminarayanan Dr. Pamela Thompson Nitin Supekar Judy M. Bradley Dr. Margreet A. Wolfert Prof. Dr. Peter A. Cohen Prof. Dr. Sandra J. Gendler Prof. Dr. Geert‐Jan Boons 《Chembiochem : a European journal of chemical biology》2014,15(10):1508-1513
The mucin MUC1 is overexpressed and aberrantly glycosylated by many epithelial cancer cells manifested by truncated O‐linked saccharides. Although tumor‐associated MUC1 has generated considerable attention because of its potential for the development of a therapeutic cancer vaccine, it has been difficult to design constructs that consistently induce cytotoxic T‐lymphocytes (CTLs) and ADCC‐mediating antibodies specific for the tumor form of MUC1. We have designed, chemically synthesized, and immunologically examined vaccine candidates each composed of a glycopeptide derived from MUC1, a promiscuous Thelper peptide, and a TLR2 (Pam3CysSK4) or TLR9 (CpG‐ODN 1826) agonist. It was found that the Pam3CysSK4‐containing compound elicits more potent antigenic and cellular immune responses, resulting in a therapeutic effect in a mouse model of mammary cancer. It is thus shown, for the first time, that the nature of an inbuilt adjuvant of a tripartite vaccine can significantly impact the quality of immune responses elicited against a tumor‐associated glycopeptide. The unique adjuvant properties of Pam3CysSK4, which can reduce the suppressive function of regulatory T cells and enhance the cytotoxicity of tumor‐specific CTLs, are likely responsible for the superior properties of the vaccine candidate 1 . 相似文献
94.
AM Abu el-Asrar AK al-Momen S al-Amro AG Abdel Gader KF Tabbara 《Canadian Metallurgical Quarterly》1996,20(4):197-204
BACKGROUND: The etiology of retinal venous occlusion in young patients is not well understood although thrombosis does occur histologically. A search for the risk factors that may lead to thrombosis is highly desirable may contribute to our understanding of the pathogenesis of this complication and may improve our therapeutic strategies. METHODS: We studied 17 patients with retinal venous occlusion. All patients were under 45 years of age (mean 37.8 +/- 7.1). Antiphospholipid antibodies (APAs) and certain hemostatic factors were determined. The results obtained in these patients were compared to those of normal controls. RESULTS: We found APAs in 8 out of 17 patients compared to 5 out of 60 controls (p = 0.0002). In patients with major trunk occlusion, there was a trend for the presence of APAs in those with poor visual acuity at presentation. Deficiencies of the coagulation inhibitor proteins C and S and antithrombin III activities were detected in 6 patients, and reduced levels of Factor XII were found in 4 patients. Levels of hematocrit, erythrocyte sedimentation rate. Fibrinogen, alpha 1-globulin, and alpha 2-globulin were significantly higher in patients compared to the controls (p = 0.019; 0.014; 0.0001; 0.011; 0.047), indicating increased blood viscosity in patients with retinal venous occlusion. CONCLUSION: Prothrombotic changes in the form of APAs and/or deficiencies of coagulation inhibitors and Factor XII may contribute to the etiology of retinal venous occlusion in young adults. Young patients with retinal venous occlusion should be evaluated for these prothrombotic states. 相似文献
95.
Influence of galanin and serotonin on the endocrine response to Hexarelin, a synthetic peptidyl GH-secretagogue, in normal women 总被引:1,自引:0,他引:1
E Arvat B Maccagno J Ramunni F Broglio F Lanfranco R Giordano A Benso R Deghenghi E Ghigo 《Canadian Metallurgical Quarterly》1998,21(10):673-679
BACKGROUND: Lack of information about the effect of insurance coverage on the demand for and use of smoking-cessation services has prevented widescale adoption of coverage for such services. METHODS: In a longitudinal, natural experiment, we compared the use and cost effectiveness of three forms of coverage with those of a standard form of coverage for smoking-cessation services that included a behavioral program and nicotine-replacement therapy. The study involved seven employers and a total of 90,005 adult enrollees. The standard plan offered 50 percent coverage of the behavioral program and full coverage of nicotine-replacement therapy. The other plans offered 50 percent coverage of both the behavioral program and nicotine-replacement therapy (reduced coverage), full coverage of the behavioral program and 50 percent coverage of nicotine-replacement therapy (flipped coverage), or full coverage of both the behavioral program and nicotine-replacement therapy. RESULTS: Estimated annual rates of use of smoking-cessation services ranged from 2.4 percent (among smokers with reduced coverage) to 10 percent (among those with full coverage). Smoking-cessation rates ranged from 28 percent (among users with full coverage) to 38 percent (among those with standard coverage). The estimated percentage of all smokers who would quit smoking per year as a result of using the services ranged from 0.7 percent (with reduced coverage) to 2.8 percent (with full coverage). The average cost to the health plan per user who quit smoking ranged from $797 (with standard coverage) to $1,171 (with full coverage). The annual cost per smoker ranged from $6 (with reduced coverage) to $33 (with full coverage). The annual cost per enrollee ranged from $0.89 (with reduced coverage) to $4.92 (with full coverage). CONCLUSIONS: Use of smoking-cessation services varies according to the extent of coverage, with the highest rates of use among smokers with full coverage. Although the rate of smoking cessation among the benefit users with full coverage was lower than the rates among users with plans requiring copayments, the effect on the overall prevalence of smoking was greater with full coverage than with the cost-sharing plans. 相似文献
96.
MW Abdel Raouf 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(1):22-29
In the present study, the removal and immobilization of 137Cs from aqueous waste solutions and a simulated waste was investigated. Two inorganic ion‐exchange complexes: di‐potassium hexacyanocobalt(II)‐ferrate(II), K2CoFe(CN)6·xH2O (KCFC), and ammonium‐12‐molybdophosphate [(NH4)3PMo12O40·aq] (AMP), were charged separately into porous nylon bags (sorption bags) of 5 µm pore diameter. The first complex (KCFC) was prepared in our laboratory. The second (AMP) was used for comparison. Easy handling and increased potential for reuse characterize the sorption bag technique. The KCFC complex was investigated by thermal gravimetric analysis (TGA) and differential thermal analysis (DTA), porosity, infra‐red (IR) and X‐ray powder diffraction (XRD). The chemical and structural investigations revealed that the KCFC complex has adequate ion‐exchange capacity and high affinity for 137Cs. The sorption bag technique showed promising results for the removal of 137Cs from aqueous waste solutions. The KCFC bags showed the highest 137Cs removal (~0.91 g g?1), at pH 8.5; AMP bags gave the highest 137Cs removal (~0.97 g g?1) in 0.1 N HNO3 and 1.5 N HNO3, both with a waste: sorbent ratio of 80 cm3 g?1. Sorption data for both KCFC and AMP revealed a good fit to the Freundlich sorption isotherm. To assess the potential of sorption bags, the used bags were regenerated in different leachants and reused in further sorption investigations. 137Cs recovery from the used sorbents was ~0.46 g g?1 using 6 N HCl as leachant for AMP, compared with ~0.253 g g?1 for KCFC using 6 N NaCl. These results indicated stronger cesium immobilization in the KCFC complex. Copyright © 2003 Society of Chemical Industry 相似文献
97.
G. Ghigo R. Gerbaldo L. Gozzelino E. Mezzetti B. Minetti A. Wisniewski 《Journal of Superconductivity and Novel Magnetism》1997,10(5):541-548
YBCO melt textured samples were studied after Au ion irradiation of two opposite surface layers of the samples and after proton
irradiation. The scaling behavior of the pinning force was studied in order to get information about mechanisms responsible
for pinning in the studied samples. Correlated disorder introduced bysurface ion irradiation is effective at high reduced temperatures and leads to the occurrence of a kink in the irreversibility line
and to the shift of this line toward higher fields and temperatures. Enhancement of critical current density,increasing with temperature and field, was observed. Random disorder due to proton irradiation does not change the irreversibility line
and only provides critical current enhancementdecreasing with temperature and field. 相似文献
98.
An investigation is described in which Nubian goats were given daily oral doses of Piper abyssinica seeds at 0.25; 1 and 5 g/kg body weight. The results of liver and kidney function tests were correlated with the clinical and pathological changes. In goats receiving the plant seed at 5 g/kg body weight/day, death occurred within 5-14 days and the main signs were bloated rumen, diarrhoea, dysponoea and ataxia. Enterohepatonephropathy was accompanied by increases in the activity of serum ALP and GGT, in the concentration of cholesterol, globulin, total lipids and urea and decreases in the level of albumin. Piper seed was toxic but not lethal to goats at doses of 0.25 and 1 g/kg body weight. 相似文献
99.
A microprocessor-based real time video analysis system has been built and used in conjunction with an oculometer to perform some aspects of eye motion analysis. An outstanding feature of this system is its ability to process data in real time so that information concerning instantaneous eye point of regard is readily available for direct observation. 相似文献
100.
M.Es.Abdel Moneim 《Wear》1981,66(1):65-75
Constant-feed-rate drilling tests under conditions of dry cutting were performed on three non-ferrous materials, namely free machining brass, aluminium and lead. The tests covered a wide range of cutting speeds. Both thrust forces and torques were affected by the drill diameter and by speed variations. Empirical relationships between the thrust force, the torque and the cutting parameters were derived for the materials used. 相似文献