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Chinese Physics Letters 2013年第1期30卷 165-168页

作者： Ahmet Kaya Şemsettin altındal YaseminŞafak Asar Zekayi sönmez Department of Physics Faculty of SciencesGazi University06500AnkaraTurkey

An Al/siO_(2)/p-si(MOs)capacitor with a thick(826Å)interfacial oxide layer(siO_(2))which is formed by using the thermal oxidation method is fabricated to investigate both frequency and applied bias voltage dependences of real and imaginary parts of dielectric constant(ϵ'andϵ")and electric modulus(M'and M"),loss tangent(tanδ)and ac electrical conductivity(σ_(ac))in a wide frequency range from 1 kHz to 1 MHz at room *** dielectric properties of the MOs capacitor are obtained using the forward and reverse bias capacitance-voltage(C–V)and conductance-voltage(G/ω–V)measurements in the applied bias voltage range 1.4–5.6 *** values ofϵ',ϵ",tanδ,M',M"and σ_(ac) are found to be strong functions of frequency and applied bias voltage in the depletion region due to excess capacitance Cex and conductance G_(ex)/ω especially at low *** experimental results show that the interfacial polarization can occur at low frequencies more easily,consequently contributing to the dispersion inϵ',ϵ",tanδ,M',M"and σ_(ac) values of the MOs *** other reason for dispersion in the dielectric properties may be attributed to a particular density distribution of interface states(Nss)localized at the si/siO_(2) interface,as well as space charge carriers and inhomogeneity of interfacial oxide *** increase in conductivity with increasing frequency can be attributed to the hopping type conduction *** can be concluded that theϵ',ϵ",tanδ,M',M"and σ_(ac) values of the Al/siO_(2)/p-si(MOs)capacitor are strongly dependent on both the frequency and applied bias voltage especially in the depletion region.

关键词： polarization dielectric interfacial

synthesis and characterization of monosize magnetic poly(glycidyl methacrylate) beads

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China Particuology 2007年第1期5卷 174-179页

作者： Evrim Banu alt■ntas■ Lokman Uzun Adil Denizli Department of Chemistry Biochemistry Division Hacettepe University Ankara Turkey

Monosize, 1.6 μm, magnetic beads of poly（glycidyl methacrylate） [M-poly（GMA）], were prepared by dispersion polymerization in the presence of Fe3O4 nano-powder. Monosize M-poly（GMA） beads were characterized by swelling tests, density measurements, electron spin resonance （EsR）, vibrating sample magnetometer （VsM） and scanning electron microscopy （sEM）. The characteristic functional groups of M-poly（GMA） beads were analyzed by Fourier transform infrared spectrometer （FTIR）. The M-poly（GMA） beads are highly uniform in size and have a spherical shape and non-porous structure. Polydispersity index （PDI） of M-poly（GMA） beads was calculated to be around 1.008. The hydrated density of the M-poly（GMA） beads measured at 25 ℃ was 1.14 g/cm^3. The content of oxirane groups on the surface of the M-poly（GMA） sample was found to be 3.46 mmol/g by using perchloric acid titration. The specific surface area of the M-poly（GMA） beads was determined to be 3.2 m^2/g. The equilibrium swelling ratio was 52%. The volume fraction of magnetite nanopowder in the M-poly（GMA） beads was found to be 4.5%. The g factor, that can be considered as a quantity characteristic of the molecules in which the unpaired electrons are located, was found to be 2.28 for M-poly（GMA）. The external magnetic field at resonance was calculated to be 2055 Gs which was found sufficient to excite all of the dipole moments present in 1.0 g of M-poly（GMA） sample.

关键词： Polyglycidyl methacrylate Monosize beads Magnetic materials

Revisiting cerebral endothelial cells in Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged froms transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant

Dielectric properties,electrical modulus and current transport mechanisms of Au/ZnO/n-si structures

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Progress in Natural science:Materials International 2018年第3期28卷 325-331页

作者： Yosef Badali ?emsettin alt?ndal ?brahim Uslu Department of Advanced Technologies Institute of Science and TechnologyGazi University Department of Physics Faculty of ScienceGazi University Department of Chemistry Education Faculty of EducationGazi University

Au/Zn O/n-si（MIs）structures were fabricated by using the RF sputtering method and their complex dielectric constant（ε*=ε’-jε’’）,electric modulus（M*=M′+j M’’）and electrical conductivity(σ=σdc+σac)values were investigated as a function of frequency（0.7 k Hz-1 MHz）and voltage(-6–（+6 V）)by capacitance-voltage（C-V）and conductance-voltage（G/ω-V）measurements to get more information on the conduction mechanisms and formation of barrier height between Au and *** lnσ-Lnf plots have two different regions corresponding to low-intermediate and high *** behavior of lnσ-lnf plots shows that the existence of two different conduction mechanisms（CMs）at low-intermediate and high ***,the reverse bias saturation current（I_o）,ideality factor（n）,barrier height(ΦBo)were determined from the forward bias I-V data and they were found as a strong function of *** value of n especially at low temperature is considerably higher than *** values ofΦB0and standard deviation（σs）were found from the intercept and slope ofΦBo-q/2k T plots as 0.551 e V and 0.075 V for the region I（80–220 K）and 1.126 e V and 0.053 V for the region II（220–400 K）,*** values ofΦBoand effective Richardson constant（A*）were found from slope and intercept of activation energy plots as 0.564 e V and 101.084 Acm-2K-2for the region I and 1.136 e V and41.87 Acm-2K-2for the region II,*** results confirm that the current-voltage-temperature（I-V-T）characteristics of the fabricated Au/Zn O/n-si sBDs can satisfactorily be explained on the basis of TE theory with double GD of the BHs.

关键词： Au/ZnO/n-si Dielectric properties Electrical modulus Current-transport mechanism Double-Gaussian distribution Barrier height

Deciphering the mechanobiology of microglia in traumatic brain injury with advanced microsystems

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Neural Regeneration Research 2025年第8期20卷 2304-2306页

作者： Anthony Procès sylvain Gabriele Univ.Grenoble Alpes InsermU1216Grenoble Institut des NeurosciencesGrenobleFrance Mechanobiology&Biomaterials Group CIRMAPResearch Institute for BiosciencesUniversity of MonsMonsBelgium

Advanced microsystems in traumatic brain injury research:Traumatic brain injury(TBI)results from a mechanical insult to the brain,leading to neuronal and axonal damage and subsequently causing a secondary *** minutes ... 详细信息

关键词： traumatic injury damage

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Improved guided bone regeneration by combined application of unmodified, fresh autologous adipose derived regenerative cells and plasma rich in growth factors:A first-in-human case report and literature review

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World Journal of stem Cells 2019年第2期11卷 124-146页

作者： ?nder solakoglu Werner G?tz Maren C Kiessling Christopher alt Christoph schmitz Eckhard U alt Dental Department of the University Medical Center Hamburg-Eppendorf Clinic for Periodontology and Implantology Department of Orthodontics Center of Dento-Maxillo-Facial MedicineUniversity of Bonn Institute of Anatomy Faculty of MedicineLMU Munich InGeneron GmbH InGeneron Inc. Isar Klinikum Munich

BACKGROUND Novel strategies are needed for improving guided bone regeneration(GBR) in oral surgery prior to implant placement, particularly in maxillary sinus augmentation(GBR-MsA) and in lateral alveolar ridge augmentation(LRA). This study tested the hypothesis that the combination of freshly isolated, unmodified autologous adipose-derived regenerative cells(UA-ADRCs), fraction 2 of plasma rich in growth factors(PRGF-2) and an osteoinductive scaffold(OIs)(UAADRC/PRGF-2/OIs) is superior to the combination of PRGF-2 and the same OIs alone(PRGF-2/OIs) in GBR-MsA/*** sUMMARY A 79-year-old patient was treated with a bilateral external sinus lift procedure as well as a bilateral lateral alveolar ridge augmentation. GBR-MsA/LRA was performed with UA-ADRC/PRGF-2/OIs on the right side, and with PRGF-2/OIs on the left side. Biopsies were collected at 6 wk and 34 wk after GBRMsA/LRA. At the latter time point implants were placed. Radiographs(32 mo follow-up time) demonstrated excellent bone healing. No radiological or histological signs of inflammation were observed. Detailed histologic,histomorphometric, and immunohistochemical analysis of the biopsies evidenced that UA-ADRC/PRGF-2/OIs resulted in better and faster bone regeneration than PRGF-2/*** GBR-MsA with UA-ADRCs, PRGF-2, and an OIs shows effectiveness without adverse effects.

关键词： Case report Cell-based therapy Guided bone regeneration Maxillary sinus augmentation Lateral alveolar ridge augmentation Unmodified autologous adipose-derived regenerative cells stem cells

First immunohistochemical evidence of human tendon repair following stem cell injection: A case report and review of literature

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World Journal of stem Cells 2021年第7期13卷 944-970页

作者： Eckhard alt Ralf Rothoerl Matthias Hoppert Hans-Georg Frank Tobias Wuerfel Christopher alt Christoph schmitz Chairman of the Board Isarklinikum MunichMunich 80331Germany Department of spine surgery Isarklinikum MunichMunich 80331Germany Department for Orthopedics and Trauma surgery Isarklinikum MunichMunich 80331Germany Chair of Neuroanatomy Institute of AnatomyFaculty of MedicineLMU MunichMunich 80336Germany Director of science and Research InGeneron GmbHMunich 80331Germany

BACKGROUND Current clinical treatment options for symptomatic,partial-thickness rotator cuff tear(sPTRCT)offer only limited potential for true tissue healing and improvement of clinical *** animal models,injections of adult stem cells isolated from adipose tissue into tendon injuries evidenced histological regeneration of tendon ***,it is unclear whether such beneficial effects could also be observed in a human tendon treated with fresh,uncultured,autologous,adipose derived regenerative cells(UA-ADRCs).A specific challenge in this regard is that UA-ADRCs cannot be labeled and,thus,not unequivocally identified in the host ***,histological regeneration of injured human tendons after injection of UA-ADRCs must be assessed using comprehensive,immunohistochemical and microscopic analysis of biopsies taken from the treated tendon a few weeks after injection of *** sUMMARY A 66-year-old patient suffered from sPTRCT affecting the right supraspinatus and infraspinatus tendon,caused by a bicycle *** day 18 post injury[day 16 post magnetic resonance imaging(MRI)examination]approximately 100 g of abdominal adipose tissue was harvested by liposuction,from which approximately 75×10^(6) UA-ADRCs were isolated within 2 ***,UA-ADRCs were injected(controlled by biplanar X-ray imaging)adjacent to the injured supraspinatus tendon immediately after *** fast clinical recovery,a follow-up MRI examination 2.5 mo post treatment indicated the need for open revision of the injured infraspinatus tendon,which had not been treated with *** this operation,a biopsy was taken from the supraspinatus tendon at the position of the injury.A comprehensive,immunohistochemical and microscopic analysis of the biopsy(comprising 13 antibodies)was indicative of newly formed tendon *** Injection of UA-ADRCs can result in regeneration of injured human tendons by formation of new tendon tissue.

关键词： stem cells Partial-thickness rotator cuff tear Tendon regeneration Adipose derived regenerative cells Cell-based therapy at point of care Case report

Complementary roles of glial cells in generating region-specific neuroinflammatory responses and phagocytosis in Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2917-2918页

作者： Leyre Ayerra Maria s.Aymerich Universidad de Navarra Facultad de CienciasDepartamento de Bioquímica y GenéticaPamplonaSpain CIMA-Universidad de Navarra PamplonaSpain IdisNA Instituto de Investigación Sanitaria de NavarraPamplonaSpain

Neuroinflammation is associated with Parkinson’s disease:Reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss of dopaminergic *** has long been considered a mere consequence of neuronal loss,but whether it promotes PD or is a key player in disease progression remains to be *** leukocyte antigen.

关键词： inflammation leukocyte generating