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Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： hassan Saad Bachar El Baba Ali Tfaily firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian mustroph David Gimbel Jonathan Grossberg Daniel L.Barrow matthew f.Gary Ali m.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

EffECT Of GAmmA RAYS IN THE PREPARATION Of POLYmER AND HYDROGEL fROm ACRYLAmIDE mONOmER

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Chinese Journal of Polymer Science 2003年第4期21卷 437-442页

作者： m.m.Alam m.f.mina f.Akhtar NRCD INST AERE GPO Box-3787 Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka Bangladesh

The formation of polymer and hydrogel from aqueous solutions having 20, 30 and 40% concentrations ofacrylamide monomer by γ-ray irradiation processing in the dose range 0.06-30 kGy using a Co-60 source and theircharacterization have been observed. Polymer conversion and gel fraction are found to depend on radiation doses. Polymerconversion increases with the increase of dose, depending on the solution concentration, where maximum conversion isachieved at 0.18, 0.16 and 0.10 kGy for 20%, 30% and 40% concentrations, respectively. On the other hand, gel fractionincreases with dose from the gel point (0.12 kGy) for all concentrations, where 100% conversion of gel occurs at doses≥5 kGy. Tensile strength, viscosity and molecular weight (m_w) of polymer samples increase with both the dose and theconcentration, showing a high value of m_w up to≈10~8. Swelling of hydrogels under water with respect to time varies due tothe variation of cross-linking density formed in the gels and the maximum swelling mainly occurs within 24 h. A remarkable change of surface morphology reveals characteristic features of monomer, polymer and hydrogel films.

关键词： Polymer Hydrogel γ-Radiation Cross-linking Swelling

SWELLING BEhaVIOR Of ACRYLAmIDE HYDROGEL IN DIffERENT SOLVENTS AND pHs

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Chinese Journal of Polymer Science 2005年第3期23卷 269-274页

作者： m.f.mina m.m.Alam Institute of Nuclear Science and Technology Atomic Energy Research EstablishmentGPO Box-3787Dhaka-1000BangladeshInstitute of Nuclear Science and TechnologyAtomic Energy Research EstablishmentGPO Box-3787Dhaka-1000Bangladesh

Swelling property of acrylamide hydrogels,prepared from aqueous solutions of acrylamide monomer havingconcentrations in the range of 10-60 wt% by ray irradiation method using a Co-60 gamma radiation source at dosesranging 1-30.0 kGy,has been investigated under various swelling *** swelling media were basically solvents(solutions),produced by dissolving methanol,ethanol,glucose,sucrose,sodium chloride and sodium persulfate individuallywith distilled water,and solutions prepared with pHs=3,7 and *** investigation was performed in order to observe theeffect of these solvents and pHs as well as the influence of monomer concentrations,radiation doses and times on swellingbehavior of *** values were found higher for hydrogels prepared with lower monomer concentrations(ca.20 wt%)and radiation doses(ca.5 kGy)and showed a leveling off tendency within 24 *** glucose solvent and the buffersolution of pH=10 revealed significant increase of swelling of hydrogels as compared to other *** areexplained based on crosslinking density in hydrogel,polymer-solvent/polymer-polymer interactions in solutions,permeability of molecules in solutions and ionization capacity of hydrogel in pH.

关键词： Acrylamide Hydrogel Co-60 gamma radiation source Swelling.

Effect of substitution group on dielectric properties of 4H-pyrano [3,2-c] quinoline derivatives thin films

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Chinese Physics B 2016年第7期25卷 440-449页

作者： H m Zeyada f m El-Taweel m m El-Nahass m m El-Shabaan Department of Physics Faculty of Science Damietta University Department of Chemistry Faculty of Science Damietta University Department of Physics Faculty of Education Ain Shams University

The AC electrical conductivity and dielectrical properties of 2-amino-6-ethyl-5-oxo-4-（3-phenoxyphenyl）-5,6-dihydro-4H-pyrano[3, 2-c]quinoline-3-carbonitrile（Ph-HPQ） and 2-amino-4-（2-chlorophenyl）-6-ethyl-5-oxo-5,6-dihydro-4H-pyrano [3, 2-c] quinoline-3-carbonitrile（Ch-HPQ） thin films were determined in the frequency range of 0.5 k Hz–5 mHz and the temperature range of 290–443 K. The AC electrical conduction of both compounds in thin film form is governed by the correlated barrier hopping（CBH） mechanism. Some parameters such as the barrier height, the maximum barrier height, the density of charges, and the hopping distance were determined as functions of temperature and frequency. The phenoxyphenyl group has a greater influence on those parameters than the chlorophenyl group. The AC activation energies were determined at different frequencies and temperatures. The dielectric behaviors of Ph-HPQ and Ch-HPQ were investigated using the impedance spectroscopy technique. The impedance data are presented in Nyquist diagrams for different temperatures. The Ch-HPQ films have higher impedance than the Ph-HPQ films. The real dielectric constant and dielectric loss show a remarkable dependence on the frequency and temperature. The Ph-HPQ has higher dielectric constants than the Ch-HPQ.

关键词： thin films quinoline derivatives dielectrical properties correlated barrier hopping

OPTImIZATION Of THE SYNTHESIS Of ACRYLAmIDE HYDROGEL BY γ-RAY IRRADIATION

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Chinese Journal of Polymer Science 2004年第3期22卷 253-258页

作者： m.A. Chowdhury m.m. Alam m.f. mina f. Akhtar S.E. Kabir Department of Chemistry Faculty of Science Jahangir Nagar University Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh Department of Chemistry Faculty of Science Jahangir Nagar University Dhaka Bangladesh

Hydrogels have been synthesized from 10%, 20%, 30%, 40%, 50% and 60% aqueous solutions of acrylamide monomer by gamma radiation employing doses in the range of 0.2-30 kGy from a Co-60 source. The effect of solution concentration, γ-ray dose, pH and time was studied in order to observe the optimizing conditions in the characterization of hydrogels. Gel fraction increases with dose for all concentrations indicating hundred-percentage conversion of gel at doses 5 kGy for homogenous solutions in the range of 20%-50% concentration. On the other hand, 10% solution provides conversion less than 86% even at 30 kGy, whereas 60% monomer makes an inhomogeneous solution which stile gives about 100% gel fraction. Swelling of hydrogels under water with respect to time varies with both the doses and concentrations due to the change of crosslinking density in the gels. The maximum volume change of hydrogels during swelling and water desorption mainly occurs within 24 h. Swelling is also enhanced with the rise of pH due to change of ionic content of the solvent. Considering the amount of gel fraction and the properties of hydrogel, the samples prepared from 20% solution at 5 kGy show better results. moreover, the effect of bacteria on hydrogel was found to be nil, suggesting a prohibition of growth of microorganism in it.

关键词： Hydrogel Acrylamide γ-radiation Swelling microorganism

Photometric Investigation of Contact Binary DY Cet Based on TESS Data

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Research in Astronomy and Astrophysics 2022年第5期22卷 121-128页

作者： m.f.Yildirim Canakkale Onsekiz mart University Astrophysics Research Center and Ulupinar Observatory17020CanakkaleTurkey Canakkale Onsekiz mart University Department of Electricity and EnergyCan Vocational School17400CanakkaleTurkey

We present a photometric analysis of the Transiting Exoplanet Survey Satellite(TESS)light curve of contact binary system DY Cet and the behavior of its orbital period *** light curve and published radial velocity data analysis was performed using the Wilson-Devinney *** a result of simultaneous analysis of the light curve with radial velocity data,the masses and radii of the system’s components were determined as m_(1)=1.55±0.02 m_(⊙),m_(2)=0.55±0.01 m_(⊙) and R_(1)=1.51±0.02 R_(⊙),R_(2)=0.95±0.02 R_(⊙),*** degree of contact(f)and mass ratio(q)of the system were determined as 23%and 0.355±0.012,*** period analysis of DY Cet was conducted for the first time in this *** was observed that the orbital period has a sinusoidal change with decreasing *** explain the orbital period change,mass transfer between components is proposed with the assumption of conservative mass,and the transfer rate was calculated to be dm/dt=1.1×10^(-7) m_(⊙)yr^(-1).A possible third component is suggested for explaining the sinusoidal change,and the mass of the unseen component was determined as 0.13 m_(⊙).The age of the DY Cet system was estimated as 3.77 Gyr.

关键词： stars eclipsing binary stars-stars fundamental parameters of stars- stars individual (DY Cet)

Impact of wastewater reuse on cobalt status in Egyptian environment

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Journal of Environmental Sciences 2003年第3期15卷 388-395页

作者： m.f. Abdel-Sabour Soil and Water Research Department Nuclear Research Center Atomic Energy Authority

Cobalt is used in the manufacture of alloys, catalysts in the petroleum industry, catalytic converters, and paint pigments. Thus the potential for Co releases into the environment is highly increased. Use of waste sludges and sewage effluent to fertilize and irrigate soils has also increased soil Co concentrations. Total cobalt contents of alluvial delta soil of Egypt show considerable variation ranging from 13.1 to 64.7 ppm. The impact of either wastewater irrigation or industrial activities on soil total Co was obvious due to accumulation of organic matter and solid waste in the surface soil samples. food crops and vegetables should not be grown on soil highly contaminated by Co. It is noteworthy that the delayed neutron activation analysis(DNAA) technique could be used successfully for total Co determination due to its high sensitivity. It is quit clearly that dust samples of Cairo City contains higher Co level, as compared to Suez Canal Region(Ismailia, Port Said and El-Suez cities). The high values in Cairo City may be due to the existence of industries around the city and the intensive traffic. To minimize Co environmental hazards, waste effluents should be treated on site. Thus, levels of potentially toxic Co needs to be continuously monitored and should be removed during several treatment processes before the disposal of these wastes.

关键词： cobalt environment Egypt

Compton profiles of NiO and TiO_2 obtained from first principles GWA spectral function

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Chinese Physics B 2016年第6期25卷 407-415页

作者： S m Khidzir m.f.m.ha.id W A T Wan Abdullah Department of Physics Universiti of Malaya

In this work,we first use momentum density studies to understand strongly correlated electron behavior,which is typically seen in transition metal *** observe that correlated electron behavior as seen in bulk NiO is due to the fermi break located in the middle of overlapping spectral functions obtained from a GW（G is Green’s function and W is the screened Coulomb interaction） approximation（GWA） calculation while in the case of TiO2 we can see that the origin of the constant momentum distribution in lower momenta is due to a pile up of spectra before the fermi *** observations are then used to compare our calculated Compton profiles with previous experimental studies of fukamachi and *** calculations for NiO are observed to follow the same trend as the experimental profile but it is seen to have a wide difference in the case of TiO2 before the fermi *** ground state momentum densities differ significantly from the quasiparticle momentum density,thus stressing the importance of the quasiparticle wave function as the input for the study of charge density and the electron localization *** we perform a calculation of the quasiparticle renormalization function,giving a quantitative description of the discontinuity of the GWA momentum density.

关键词： elastic and Compton scattering density functional theory local density approximation gradient and other corrections elements oxides nitrides borides carbides chalcogenides

Surface morphology and impurity distribution of electron beam recrystallized silicon films on low cost substrates for solar cell absorber

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Rare metals 2006年第z1期25卷 195-200页

作者： GROmBALL f müLLER J Department of mikrosystemtechnik Technische Universitt Hamburg-Harburg Hamburg 21073 Germany

A line shaped electron beam recrystallised polycrystalline silicon film on the low cost substrate was investigated for the use of the solar cell absorber. The applied EB energy density strongly influences the surface morphology of the film system. Lower EB energy density results in droplet morphology and the rougher SiO2 capping layer due to the low fluidity. With the energy increasing, the capping layer becomes smooth and continuous and less and small pinholes form in the silicon film. Tungstendisilicide (WSi2) is formed at the interface tungsten/silicon but also at the grain boundaries of the silicon. Because of the fast melting and cooling of the silicon film, the eutectic of silicon and tungstendisilicide mainly forms at the grain boundary of the primary silicon dendrites. The SEm-EDX analysis shows that there are no chlorine and hydrogen in the area surrounding a pinhole after recrystallization because of outgassing during the solidification.

关键词： polycrystalline silicon film solar cell recrystallization energy surface morphology outgassing