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The Landég Factors for the 6S_(1/2)and 5D_(3/2,5/2)States of Ba^(+)Ions
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作者 Bing-Bing Li Jun Jiang +2 位作者 Lei Wu Deng-Hong Zhang Chen-Zhong Dong 《Chinese Physics Letters》 2025年第6期52-57,共6页
The Landé g factors of Ba+are very important in high-precision measurement physics.The wave functions,energy levels,and Landég factors for the 6s ^(2)S_(1/2) and 5d 2D_(3/2,5/2) states of Ba+ions were calcul... The Landé g factors of Ba+are very important in high-precision measurement physics.The wave functions,energy levels,and Landég factors for the 6s ^(2)S_(1/2) and 5d 2D_(3/2,5/2) states of Ba+ions were calculated using the multi-configuration Dirac-Hartree-Fock method and the model-quantum electrodynamics(QED)method.The contributions of the electron correlation effects and QED effects were discussed in detail.The transition energies are in excellent agreement with the experimental results,with differences of approximately 5 cm^(−1).The presently calculated g factor of 2.0024905(16)for the 6S1/2 agrees very well with the available experimental and theoretical results,with a difference at a level of 10^(−6).For the 5D_(3/2,5/2) states,the present results of 0.7993961(126)and 1.2003942(190)agree with the experimental results of 0.7993278(3)[Phys.Rev.A 541199(1996)]and 1.20036739(14)[Phys.Rev.Lett.124193001(2020)]very well,with differences at the level of 10−5. 展开更多
关键词 transition energies multi configuration dirac hartree fock method model quantum electrodynamics land g factors electron correlation effects qed effects wave functionsenergy
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Energy Spectra,g Factors and Their Pressure—Induced and /or Thermal Shifts of SrTiO3:Cr^3+ and SrTiO3:Mn^4+ I:energy Spectra and g Factors at Normal Pressure 被引量:1
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作者 ZHANGJi-Ping MADong-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第4期491-496,共6页
With the strong-field scheme and cubic bases, the complete d<SUP>3</SUP> energy matrix in a tetragonally distorted cubic-field has been constructed. By diagonalizing this matrix, the energy spectra of SrTi... With the strong-field scheme and cubic bases, the complete d<SUP>3</SUP> energy matrix in a tetragonally distorted cubic-field has been constructed. By diagonalizing this matrix, the energy spectra of SrTiO<SUB>3</SUB>:Cr<SUP>3+</SUP> and SrTiO<SUB>3</SUB>:Mn<SUP>4+</SUP> at normal pressure and various temperatures have been calculated. Correspondingly, the FORTRAN program calculating the g factor of the ground state has been worked out. By using the program and the wavefunction obtained from diagonalizing the complete energy matrix, the g factors of the ground state of SrTiO<SUB>3</SUB>:Cr<SUP>3+</SUP> and SrTiO<SUB>3</SUB>:Mn<SUP>4+</SUP> at normal pressure and room temperature have been evaluated. The calculated results are in good agreement with the optical-spectral and EPR experimental data. The comparison and analysis of the results of two crystals have been made. It is demonstrated that the covalency of the bonding between Mn<SUP>4+</SUP> and ligands (O<SUP>2-</SUP>) in SrTiO<SUB>3</SUB>:Mn<SUP>4+</SUP> is stronger than the one of the bonding between Cr<SUP>3+</SUP> and ligands (O<SUP>2-</SUP>) in SrTiO<SUB>3</SUB>:Cr<SUP>3+</SUP>. It is shown that the obtained wavefunctions and values of parameters are reasonable. 展开更多
关键词 crystal fields energy spectrum optical properties g factors COVALENCY
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Mobilization of Peripheral Blood Stem Cells Using Regimen Combining Docetaxel with Granulocyte Colony-stimulating Factor in Breast Cancer Patients 被引量:4
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作者 Jing Yu Jun Ren +8 位作者 Li-jun Di Guo-hong Song Yu-lin Zhu Jie Zhang Xu Liang Li Che Han-fang Jiang Jun Jia Chun-rong Zhang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2011年第1期49-53,共5页
Objective:To evaluate the effectiveness and safety of the mobilization of peripheral blood hematopoietic stem cells by combining docetaxel with granulocyte colony-stimulating factor(G-CSF) in breast cancer patients... Objective:To evaluate the effectiveness and safety of the mobilization of peripheral blood hematopoietic stem cells by combining docetaxel with granulocyte colony-stimulating factor(G-CSF) in breast cancer patients.Methods:A total of 57 breast cancer patients were treated with docetaxel 120 mg/m2.When the white blood cell(WBC) count decreased to 1.0×109/L,patients were given G-CSF 5-g/kg daily by subcutaneous injection until the end of apheresis.Peripheral blood mononuclear cells(MNC) were isolated by Cobe Spectra Apheresis System.The percentage of CD34+ cell was assayed by flow cytometry.Results:At a median 6 of days(range 3-8) after the administration of docetaxel,the median WBC count decreased to 1.08×109/L(range 0.20-2.31).The median duration of G-CSF mobilization was 3 days(range 2-7).The MNC collection was conducted 8-12 days(median 10 days) after docetaxel treatment.The median MNC was 5.35×108/kg(range 0.59-14.07),the median CD34+ cell count was 2.43×106/kg(range 0.16-16.69).The CD34+ cell count was higher than 1.00×106/kg in 47 of 57 cases(82.46%) and higher than 2.00×106/kg in 36 cases(63.16%).The CD34+ cell count was higher than 2.00×106/kg in 27 collections(23.68%).The MNC count and the CD34+ cell count were correlated with the bottom of WBC after docetaxel chemotherapy(r=0.364,0.502,P=0.005,0.000).The CD34+ cell count was correlated with the MNC count(r=0.597,P=0.000).The mobilization and apheresis were well tolerated in all patients.Mild perioral numbness and numbness of hand or feet were observed in 3 cases.No serious adverse events were reported.Conclusion:Mobilization of peripheral blood hematopoietic stem cell by combining docetaxel with G-CSF was effective and safety in breast cancer patients. 展开更多
关键词 DOCETAXEL granulocyte colony-stimulating factorg-CSF) MOBILIZATION Stem cell
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Determining the sign of g factor via time-resolved Kerr rotation spectroscopy with a rotatable magnetic field
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作者 谷晓芳 钱轩 +2 位作者 姬扬 陈林 赵建华 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期415-418,共4页
Time-resolved Kerr rotation spectroscopy is used to determine the sign of the g factor of carriers in a semiconductor material, with the help of a rotatable magnetic field in the plane of the sample. The spin precessi... Time-resolved Kerr rotation spectroscopy is used to determine the sign of the g factor of carriers in a semiconductor material, with the help of a rotatable magnetic field in the plane of the sample. The spin precession signal of carriers at a fixed time delay is measured as a function of the orientation of the magnetic field with a fixed strength B. The signal has a sine-like form and its phase determines the sign of the g factor of carriers. As a natural extension of previous methods to measure the (time-resolved) photoluminescence or time-resolved Kerr rotation signal as a function of the magnetic field strength with a fixed orientation, such a method gives the correct sign of the g factor of electrons in GaAs. Furthermore, the sign of carriers in a (Ga, Mn)As magnetic semiconductor is also found to be negative. 展开更多
关键词 g factor time-resolved Kerr rotation gallium arsenide rotatable magnetic field
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Energy Spectrum, g Factors, Strain-Induced Level-Splittings and R-Line Thermal Shift of MgO:V^(2+)
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作者 ZHANG Zheng-Jie MA Dong-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期511-516,共6页
Traditional ligand-field theory has to be improved by taking into account both pure electronic contribution and electron-phonon interaction one (including lattice-vibrational relaxation energy). By means of improved... Traditional ligand-field theory has to be improved by taking into account both pure electronic contribution and electron-phonon interaction one (including lattice-vibrational relaxation energy). By means of improved ligand-field theory, the R line, t^322T1 and t^322T2 lines, t^22(^3T1)e^4T2, t^22(^3T1)e^4T1 and t2e^2(^4A2)4T1 bands, g factors of t^32 ^4A2 and t32E, four strain-induced level-splittings and R-line thermal shift of MgO:V^2+ have been calculated. The results are in very good agreement with the experimental data. It is found that for MgO:V^2+, the contributions due to electronphonon interaction (EPI) come from the first-order term; the contributions from the second-order and higher terms are insignificant. In thermal shift of R line of MgO:V^2+, the temperature-dependent contribution due to EPI is dominant. The results obtained in this work may be used in theoretical calculations of other effects of EPI. 展开更多
关键词 improved ligand-field theory electron-phonon interaction energy spectrum strain-induced split-ting thermal shift g factor
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Theoretical Studies of Energy Spectra and g Factors of Cr3+-Doped YAl3(BO3)4
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作者 ZHANG Ji-Ping CHEN Gang ZHOU Hua-Bin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1121-1125,共5页
With the strong-field scheme and trigonal bases, by diagonalizing the complete d^3 energy matrix in a trigonally distorted cubic-field, the energy spectra and wavefunctions of YAl3(BO3)4:Cr^3+ have been calculated... With the strong-field scheme and trigonal bases, by diagonalizing the complete d^3 energy matrix in a trigonally distorted cubic-field, the energy spectra and wavefunctions of YAl3(BO3)4:Cr^3+ have been calculated. The rates of change of levels with respect to various parameters and the contributions to levels from various parameters are calculated, and the physical origins of various levels or splittings have been clearly and quantitatively shown. By using the wavefunctions obtained from diagonalizing the complete energy matrix, the g factors of the ground state of YAl3 (BO3 )4;Cr^3+ have been evaluated. The calculated results are in good agreement with the optical-spectral and EPR experimental data. It is demonstrated that the bonding between Cr^3+ and ligands (O^2-) is ionic. 展开更多
关键词 crystal fields energy spectrum g factor electronic paramagnetic resonance
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The Influence of Mesoscopic Characteristics of Mineral Powders Fillers on the Rutting Factor(G^(*)/sinδ)of Asphalt Mortar
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作者 LIAO Jun DENG Tao +6 位作者 GONG Hongwei LI Zhen TANG Yongtao CHEN Kai SHI Lei QIAN Xiaolong DONG Qian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1118-1125,共8页
This study aims to investigate the efiect of the mesoscopic characteristics of mineral powder fillers on the rutting resistance of asphalt mortar.Extraction and sieving tests were used to obtain the buton rock asphalt... This study aims to investigate the efiect of the mesoscopic characteristics of mineral powder fillers on the rutting resistance of asphalt mortar.Extraction and sieving tests were used to obtain the buton rock asphalt(BRA)ash with particle size smaller than 0.075 mm,which is consistent with that of the conventional mineral powder.The mesoscopic characteristics of BRA ash and conventional mineral powder were measured by SEM image analysis and the osmotic free pressure water method.Mesoscopic structure models of structural and free asphalts in mortar were obtained.The 70#matrix asphalt was used to prepare two kinds of asphalt mortar with BRA ash and conventional mineral powders fillers.The rutting factor of the two asphalt mortars was tested by dynamic shear test(DSR).Test results show that the ash extracted from BRA has a similar mesoscopic classification with the conventional mineral powder.Still,its fractal dimensions are larger,indicating the particles in BRA ash have more complex shapes and rougher surfaces,which is beneficial for forming structural asphalt and subsequently increasing the rutting factor(G*/sinδ),i e,improving the rutting resistance of the asphalt mortar. 展开更多
关键词 asphalt mortar mineral powder fllers mesoscopic characteristic rutting factor(g*/sinδ)
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Mononuclear cells from the cord blood and granulocytecolony stimulating factor-mobilized peripheral blood:is there a potential for treatment of cerebral palsy? 被引量:4
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作者 Hani Koh Kyoujung Hwang +2 位作者 Hae-Young Lim Yong-Joo Kim Young-Ho Lee 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第12期2018-2024,共7页
To investigate a possible therapeutic mechanism of cell therapy in the field of cerebral palsy using granulocyte-colony stimulating factor(G-CSF)-mobilized peripheral blood mononuclear cells(m PBMCs),we compared t... To investigate a possible therapeutic mechanism of cell therapy in the field of cerebral palsy using granulocyte-colony stimulating factor(G-CSF)-mobilized peripheral blood mononuclear cells(m PBMCs),we compared the expression of inflammatory cytokines and neurotrophic factors in PBMCs and m PBMCs from children with cerebral palsy to those from healthy adult donors and to cord blood mononuclear cells donated from healthy newborns.No significant differences in expression of neurotrophic factors were found between PBMCs and m PBMCs.However,in cerebral palsy children,the expression of interleukin-6 was significantly increased in m PBMCs as compared to PBMCs,and the expression of interleukin-3 was significantly decreased in m PBMCs as compared to PBMCs.In healthy adults,the expression levels of both interleukin-1βand interleukin-6 were significantly increased in m PBMCs as compared to PBMCs.The expression of brain-derived neurotrophic factors in m PBMC from cerebral palsy children was significantly higher than that in the cord blood or m PBMCs from healthy adults.The expression of G-CSF in m PBMCs from cerebral palsy children was comparable to that in the cord blood but significantly higher than that in m PBMCs from healthy adults.Lower expression of pro-inflammatory cytokines(interleukin-1β,interleukin-3,and-6)and higher expression of anti-inflammatory cytokines(interleukin-8 and interleukin-9)were observed from the cord blood and m PBMCs from cerebral palsy children rather than from healthy adults.These findings indicate that m PBMCs from cerebral palsy and cord blood mononuclear cells from healthy newborns have the potential to become seed cells for treatment of cerebral palsy. 展开更多
关键词 neurotrophic factors inflammatory cytokines cord blood g-CSF mobilized peripheralblood mononuclear cell cerebral palsy CHILDREN neural regeneration
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Granulocyte Colony-Stimulating Factor Enhances the Anticancer Effects of Cisplatin against Lung Cancer by Promoting Angiogenesis
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作者 Yun-Mo Li Yasushi Ohno +9 位作者 Norihiko Funaguchi Takenobu Gomyo Yuka Sasaki Sayaka Toyoshi Daizo Kaito Komei Yanase Junki Endo Fumitaka Ito Masanori Kawasaki Shinya Minatoguchi 《Advances in Lung Cancer》 2017年第1期1-11,共11页
The G-CSF is used as a therapeutic drug of the febrile neutropenia in lung cancer chemotherapy, however, there were few reports that showed the effects of combination effects of G-CSF and anticancer drugs against lung... The G-CSF is used as a therapeutic drug of the febrile neutropenia in lung cancer chemotherapy, however, there were few reports that showed the effects of combination effects of G-CSF and anticancer drugs against lung cancer. In the present study, we investigated the effects of G-CSF and the combination effects of G-CSF and cisplatin on lung cancer growth. We investigated the effect of G-CSF against the LL-2 and KLN-205 cells by MTT assay and tried to detect the G-CSF receptor by RT-PCR. Next, to analyze the G-CSF effects in vivo, we transplanted the LL-2 into C57BL/6 mice, intraperitoneally administered G-CSF (30 micro/kg/day) with or without cisplatin (5 mg/kg), measured the tumor size and analyzed pathologically by HE and immunostaining. In vitro analyses, G-CSF showed no effects in LL-2 and KLN-205 cells, and RT-PCR revealed no G-CSF receptor mRNA. In vivo analyses, G-CSF alone did not significantly suppress tumor growth. However, concurrent G-CSF administration with cisplatin significantly enhanced the tumor suppressing effect of cisplatin in early stage of tumor growth. The analysis data of vWF immunostaining indicated that the neovascularization in the peripheral region of the tumors was more enhanced in G-CSF treatment mice. ELISA assay revealed that G-CSF did not influence the serum concentration of TNF-alpha and IL-12 in tumor-bearing mice. This study suggests that concurrent (combination) administration of cisplatin with G-CSF is a safe and effective method for enhancing anticancer effects and reducing chemotherapeutic agent-induced myelosuppression. 展开更多
关键词 gRANULOCYTE Colony-Stimulating factor Lung Cancer g-CSF Receptor ANgIOgENESIS ANTICANCER Agent CISPLATIN TNF-ALPHA IL-12
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Curcumol ameliorates diabetic retinopathy via modulating fat mass and obesity-associated protein-demethylated MAF transcription factor G antisense RNA 1
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作者 Han Rong Yu Hu Wei Wei 《World Journal of Diabetes》 2025年第4期220-235,共16页
BACKGROUND Diabetic retinopathy(DR)is a major microvascular complication of diabetes mellitus,leading to significant visual impairment and blindness among adults.Current treatment options are limited,making it essenti... BACKGROUND Diabetic retinopathy(DR)is a major microvascular complication of diabetes mellitus,leading to significant visual impairment and blindness among adults.Current treatment options are limited,making it essential to explore novel therapeutic strategies.Curcumol,a sesquiterpenoid derived from traditional Chinese medicine,has shown anti-inflammatory and anti-cancer properties,but its potential role in DR remains unclear.AIM To investigate the therapeutic effects of curcumol on the progression of DR and to elucidate the underlying molecular mechanisms,particularly its impact on the fat mass and obesity-associated(FTO)protein and the long non-coding RNA(lncRNA)MAF transcription factor G antisense RNA 1(MAFG-AS1).METHODS A streptozotocin-induced mouse model of DR was established,followed by treatment with curcumol.Retinal damage and inflammation were evaluated through histological analysis and molecular assays.Human retinal vascular endothelial cells were exposed to high glucose conditions to simulate diabetic environments in vitro.Cell proliferation,migration,and inflammation markers were assessed in curcumoltreated cells.LncRNA microarray analysis identified key molecules regulated by curcumol,and further experiments were conducted to confirm the involvement of FTO and MAFG-AS1 in the progression of DR.RESULTS Curcumol treatment significantly reduced blood glucose levels and alleviated retinal damage in streptozotocininduced DR mouse models.In high-glucose-treated human retinal vascular endothelial cells,curcumol inhibited cell proliferation,migration,and inflammatory responses.LncRNA microarray analysis identified MAFG-AS1 as the most upregulated lncRNA following curcumol treatment.Mechanistically,FTO demethylated MAFG-AS1,stabilizing its expression.Rescue experiments demonstrated that the protective effects of curcumol against DR were mediated through the FTO/MAFG-AS1 signaling pathway.CONCLUSION Curcumol ameliorates the progression of DR by modulating the FTO/MAFG-AS1 axis,providing a novel therapeutic pathway for the treatment of DR.These findings suggest that curcumol-based therapies could offer a promising alternative for managing this debilitating complication of diabetes. 展开更多
关键词 Diabetic retinopathy CURCUMOL MAF transcription factor g antisense RNA 1 Fat mass and obesity-associated protein Diabetes mellitus
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G蛋白抑制性α亚单位1和3介导神经生长因子通路在阿尔茨海默病小鼠术后学习记忆中的作用
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作者 拾翠翠 张玉凤 +4 位作者 张浩 崔恩惠 晏明 孙岳 孙剑 《中华老年心脑血管病杂志》 北大核心 2025年第11期1562-1566,共5页
目的探讨异氟醚麻醉对阿尔茨海默病(Alzheimer’s disease,AD)小鼠认知功能、海马神经生长因子(nerve growth factor,NGF)及其受体酪氨酸激酶A(tyrosine receptor kinase A,TrkA)信号通路的影响,并验证G蛋白抑制性α亚单位1/3(G protein... 目的探讨异氟醚麻醉对阿尔茨海默病(Alzheimer’s disease,AD)小鼠认知功能、海马神经生长因子(nerve growth factor,NGF)及其受体酪氨酸激酶A(tyrosine receptor kinase A,TrkA)信号通路的影响,并验证G蛋白抑制性α亚单位1/3(G protein inhibitoryαsubunit,Gαi1/3)在该通路中的作用。方法选择12只野生雄性小鼠为对照组,另选48只雄性APP/PSI转基因小鼠,制备AD小鼠术后认知功能障碍(post operative cognitive dysfunction,POCD)模型,将其分为AD组、AD+POCD组、腺病毒空载组、Gαi1/3过表达组,每组12只。通过Morris水迷宫和新物体识别实验评估各组学习记忆功能;采用Western blot法检测海马组织β淀粉样蛋白1-42(amyloidβ-protein 1-42,Aβ1-42)、白细胞介素6(interleukin-6,IL-6)、肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)、突触结合蛋白1(synaptotagmin-1,Syt1)、突触素1(synapsin-1,SYN1)及NGF、磷酸化TrkA(phosphorylation-TrkA,p-TrkA)、Gαi1/3、磷酸化接头蛋白Gab1(phosphorylation-Gab1,p-Gab1)表达情况。结果与对照组及AD组比较,AD+POCD组第2~4天逃避潜伏期显著延长(P<0.05),Aβ1-42、IL-6、TNF-α表达显著增加(P<0.05),Syt1、SYN1、NGF、p-TrkA、Gαi1/3、p-Gab1表达显著降低,差异有统计学意义(P<0.05);与AD+POCD组及腺病毒空载组比较,Gαi1/3过表达组第2~4天逃避潜伏期显著缩短(P<0.05),Syt1、SYN1、Gαi1/3、p-Gab1表达显著增加(P<0.05)。Gαi1/3过表达组Aβ1-42(2.00±0.39 vs 3.38±0.38)、IL-6(1.65±0.37 vs 3.36±0.39)、TNF-α(1.58±0.30 vs 2.90±0.31)表达显著低于腺病毒空载组(P<0.05)。结论异氟醚麻醉可加重AD小鼠POCD,过表达Gαi1/3可通过激活Gab1磷酸化改善认知功能。 展开更多
关键词 阿尔茨海默病 术后认知并发症 g蛋白抑制性α亚单位1/3 神经生长因子
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Electron G-Factor Anomaly and the Charge Thickness
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作者 Arlen Young 《Journal of Modern Physics》 2024年第4期435-447,共13页
The electron g-factor relates the magnetic moment to the spin angular momentum. It was originally theoretically calculated to have a value of exactly 2. Experiments yielded a value of 2 plus a very small fraction, ref... The electron g-factor relates the magnetic moment to the spin angular momentum. It was originally theoretically calculated to have a value of exactly 2. Experiments yielded a value of 2 plus a very small fraction, referred to as the g-factor anomaly. This anomaly has been calculated theoretically as a power series of the fine structure constant. This document shows that the anomaly is the result of the electron charge thickness. If the thickness were to be zero, g = 2 exactly, and there would be no anomaly. As the thickness increases, the anomaly increases. An equation relating the g-factor and the surface charge thickness is presented. The thickness is calculated to be 0.23% of the electron radius. The cause of the anomaly is very clear, but why is the charge thickness greater than zero? Using the model of the interior structure of the electron previously proposed by the author, it is shown that the non-zero thickness, and thus the g-factor anomaly, are due to the proposed positive charge at the electron center and compressibility of the electron material. The author’s previous publication proposes a theory for splitting the electron into three equal charges when subjected to a strong external magnetic field. That theory is revised in this document, and the result is an error reduced to 0.4% in the polar angle where the splits occur and a reduced magnetic field required to cause the splits. 展开更多
关键词 Electron g-factor Anomaly Electron Charge Thickness Electron Positive Charge Electron Mass Thickness Electron Fractionalization Splitting the Electron Electron Compressibility factor
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G-四链体招募转录因子调控基因转录
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作者 齐鸣 王文梦 李当当 《中国生物化学与分子生物学报》 北大核心 2025年第4期494-504,共11页
在基因转录的经典模型中,转录因子通过与含有其“共有基序”的双链DNA(double-stranded DNA,dsDNA)结合来调控靶基因转录。与dsDNA不同,G-四链体是一种非典型的核酸二级结构,由富含鸟嘌呤的序列形成,参与调节基因转录等多种生物学过程,... 在基因转录的经典模型中,转录因子通过与含有其“共有基序”的双链DNA(double-stranded DNA,dsDNA)结合来调控靶基因转录。与dsDNA不同,G-四链体是一种非典型的核酸二级结构,由富含鸟嘌呤的序列形成,参与调节基因转录等多种生物学过程,是目前分子生物学领域研究热点。近期,多个研究组发现,与dsDNA相比,G-四链体结构更高效地招募转录因子结合到启动子上,从而激活靶基因表达。然而,目前对这种非经典的基因转录调控模型缺乏全面的总结和探讨。本文介绍了G-四链体结构特点及检测该结构的技术。G-四链体包括分子内和分子间类型,其中分子内G-四链体又分为平行、反平行和杂交类型;该结构可通过圆二色谱、核磁共振光谱和凝胶迁移等技术进行鉴定。进而讨论了G-四链体在基因转录中的调节功能。G-四链体主要在基因启动子区高度富集;早期研究揭示,G-四链体可抑制基因转录,而近期的大量研究证明,该结构具备招募转录因子激活基因转录的新功能。最后,总结了具有G-四链体结合活性的转录因子的分类,包括C 2H 2锌指、叉状头/翼状螺旋、以及p53结构域的转录因子,且DNA结合结构域决定转录因子与G-四链体结合;并对该领域的后续研究方向进行了展望。总之,本文为理解“G-四链体作为转录激活的顺式作用元件”的观点提供重要指导。 展开更多
关键词 g-四链体 转录因子 启动子 基因转录
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血清HLA-G、PLGF、IL-35对夫精宫腔内人工授精妊娠结局的预测价值 被引量:1
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作者 欧阳杰 凡永 刘萍 《生殖医学杂志》 2025年第2期164-170,共7页
目的分析血清人类白细胞抗原-G(HLA-G)、胎盘生长因子(PLGF)、白介素-35(IL-35)水平对夫精宫腔内人工授精(IUI)患者妊娠结局的预测价值。方法回顾性分析2021年3月至2023年10月在海南西部中心医院行IUI患者的临床资料,共358个周期。根据... 目的分析血清人类白细胞抗原-G(HLA-G)、胎盘生长因子(PLGF)、白介素-35(IL-35)水平对夫精宫腔内人工授精(IUI)患者妊娠结局的预测价值。方法回顾性分析2021年3月至2023年10月在海南西部中心医院行IUI患者的临床资料,共358个周期。根据妊娠结局分为妊娠组(n=62)和未妊娠组(n=296)。采用ELISA法检测患者血清HLA-G、PLGF、IL-35水平,比较各组间的一般资料、各血清因子水平;采用多因素Logistic回归分析IUI患者妊娠结局的影响因素,绘制受试者工作特征(ROC)曲线分析HLA-G、PLGF、IL-35水平对IUI患者妊娠结局的预测价值,采用Spearman及Pearson法分析HLA-G、PLGF、IL-35水平与年龄、卵巢功能指标的相关性。结果与妊娠组相比,未妊娠组的年龄、不孕年限显著升高(P<0.05),HCG日优势卵泡数>1的比例、抗苗勒管激素(AMH)水平显著降低(P<0.05),血清HLA-G、PLGF、IL-35水平显著降低(P<0.05)。Logistic回归分析显示,年龄[OR=1.405,95%CI(1.031,1.915),P=0.031]是患者妊娠结局的危险因素,血清HLA-G[OR=0.785,95%CI(0.618,0.997),P=0.047]、PLGF[OR=0.733,95%CI(0.559,0.961),P=0.024]、IL-35[OR=0.786,95%CI(0.624,0.991),P=0.041]均为妊娠结局的保护因素。ROC曲线分析表明,HLA-G、PLGF、IL-35水平、年龄以及联合预测患者妊娠结局的曲线下面积(AUC)分别为0.819、0.819、0.773、0.645、0.938,联合预测的灵敏度为83.11%,特异度为96.77%,联合预测显著优于HLA-G(Z=3.912,P=0.001)、PLGF(Z=4.111,P<0.001)、IL-35(Z=4.831,P<0.001)水平及年龄(Z=7.116,P<0.001)单独预测。相关性分析结果显示,HLA-G、IL-35水平与AMH水平呈正相关(P<0.05),PLGF水平与年龄呈负相关(P<0.05)、与AMH水平呈正相关(P<0.05)。结论经夫精IUI后未妊娠患者血清HLA-G、PLGF、IL-35水平降低,三者与年龄联合分析对妊娠结局具有一定辅助预测价值。 展开更多
关键词 夫精宫腔内人工授精 人类白细胞抗原-g 胎盘生长因子 白介素-35 妊娠结局 预测价值
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GPSM1在肺腺癌中的表达及其对肺腺癌细胞糖酵解的调控与潜在机制
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作者 程金凤 江万里 《武汉大学学报(医学版)》 2025年第6期729-737,共9页
目的:探讨G蛋白信号调节受体1(GPSM1)在肺腺癌组织和细胞中的表达及其对肺腺癌细胞侵袭和迁移的影响与可能的机制。方法:通过生物信息学方法分析TCGA数据库,探索GPSM1在肺腺癌组织与正常肺组织中的表达差异,并使用Western Blot法和qPCR... 目的:探讨G蛋白信号调节受体1(GPSM1)在肺腺癌组织和细胞中的表达及其对肺腺癌细胞侵袭和迁移的影响与可能的机制。方法:通过生物信息学方法分析TCGA数据库,探索GPSM1在肺腺癌组织与正常肺组织中的表达差异,并使用Western Blot法和qPCR法检测人正常肺支气管肺泡上皮细胞BEAS-2B和人肺腺癌细胞A549、H1299、H460中GPSM1的表达水平,并选取GPSM1表达水平更低的H1299和H460细胞进行后续实验。构建GPSM1过表达质粒转染肺腺癌细胞,通过Transwell实验和细胞划痕实验分别检测过表达和敲低GPSM1对肺腺癌细胞侵袭和迁移的影响。使用LinkedOmics工具在线分析肺腺癌中GPSM1共表达基因并进行富集分析。通过检测糖酵解关键酶mRNA表达水平及细胞能量代谢分析明确GPSM1对肺腺癌细胞糖酵解的影响,并使用HIF-1α激动剂探索GPSM1/HIF-1α轴对肺腺癌细胞侵袭和迁移能力的影响。结果:GPSM1在肺腺癌组织和细胞中均呈低表达。过表达GPSM1后,肺腺癌细胞侵袭和迁移能力显著降低;肺腺癌内GPSM1表达参与多种生物学过程;过表达GPSM1后,肺腺癌细胞糖酵解能力下降,且糖酵解本身不影响GPSM1表达水平;GPSM1过表达伴随肺腺癌细胞内HIF-1α表达下调,且激活HIF-1α后肺腺癌细胞迁移和侵袭能力得到恢复。结论:GPSM1在肺腺癌组织和细胞中均呈低表达,其表达水平下调可能通过激活HIF-1α/糖酵解通路促进肺腺癌细胞侵袭和迁移。 展开更多
关键词 肺腺癌 g蛋白信号调节受体1 侵袭 迁移 糖酵解 缺氧诱导因子1Α
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定位格架G因子光学测量方法及可靠性评定
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作者 郑家国 《机电产品开发与创新》 2025年第6期133-135,共3页
定位格架G因子与核电站燃料棒破损直接相关。建立可靠的G因子的测量方法,是核燃料元件制造厂必备的测量技术。本方法在国内首次利用光学方法实现了G因子的测量。通过可靠性评定试验,验证了该测量方法的测量准确度为0.0131 mm,重复性为0.... 定位格架G因子与核电站燃料棒破损直接相关。建立可靠的G因子的测量方法,是核燃料元件制造厂必备的测量技术。本方法在国内首次利用光学方法实现了G因子的测量。通过可靠性评定试验,验证了该测量方法的测量准确度为0.0131 mm,重复性为0.000063mm、复现性为0.000136mm,测量不确定度(扩展不确定度)为0.032 mm,满足G因子测量不确定度U≤0.05 mm的技术指标。本光学测量方法已完成16.9万余件定位格架G因子检测。该方法运行稳定可靠,0故障,0漏检率,0误检率,确保G因子工艺能力指数Cpk持续保持>1.9的优秀质量控制水平。 展开更多
关键词 核燃料组件 定位格架g因子 光学测量方法 可靠性评定
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Ag_(3)PO_(4)/P-g-C_(3)N_(4)复合材料光催化降解双酚S:影响因素及机理研究 被引量:3
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作者 王国庆 陈苗 +2 位作者 徐敏强 孙善伟 张恒 《环境科学学报》 北大核心 2025年第3期156-169,共14页
P掺杂g-C_(3)N_(4)(P-g-C_(3)N_(4))具有比g-C_(3)N_(4)更窄的带隙,能提高其对可见光的利用率并提高光催化性能.采用热聚合和原位沉积法制备了Ag_(3)PO_(4)/P-g-C_(3)N_(4)(A/CN)复合材料,并对其结构、形貌特征、光学性质及元素组成进... P掺杂g-C_(3)N_(4)(P-g-C_(3)N_(4))具有比g-C_(3)N_(4)更窄的带隙,能提高其对可见光的利用率并提高光催化性能.采用热聚合和原位沉积法制备了Ag_(3)PO_(4)/P-g-C_(3)N_(4)(A/CN)复合材料,并对其结构、形貌特征、光学性质及元素组成进行了分析,探究了A/CN在可见光下降解双酚S(BPS)的性能,考察了溶液初始pH、溶解性有机质(DOM)及无机盐离子(HCO_(3)^(-)、NO_(3)^(-))对BPS降解的影响,并探讨了A/CN降解BPS的机理.结果表明:A/CN具有比Ag_(3)PO_(4)或P-g-C_(3)N_(4)更优异的光催化性能,能在120 min内降解95.02%的BPS(10 mg·L^(-1));酸性或碱性条件均会抑制BPS的降解,HCO_(3)^(-)和DOM投加均对BPS的降解表现出低浓度促进和高浓度抑制的双重作用,NO_(3)^(-)的添加抑制了BPS的降解;空穴(h^(+))和·O_(2)^(-)是A/CN光催化降解BPS体系的主要活性物种,A/CN的复合结构及Ag纳米颗粒的形成显著抑制了复合材料中光生电子与h^(+)的复合,从而显著提高了其光催化性能.A/CN对实际水环境中的BPS也表现出较好的去除效果,说明其具有良好的实际应用前景,为光催化降解BPS提供了新的思路和理论基础. 展开更多
关键词 Ag_(3)PO_(4)/P-g-C_(3)N_(4) 光催化 双酚S 影响因素 降解机理
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MOGAD患者并发癫痫发作的临床特点及危险因素分析
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作者 丰志鹏 朱颖杰 +1 位作者 李慧珍 宋志秀 《海南医学》 2025年第9期1247-1250,共4页
目的探讨髓鞘少突胶质细胞糖蛋白免疫球蛋白G抗体相关疾病(MOGAD)患者并发癫痫发作的临床特点及危险因素。方法前瞻性选择2022年1月至2024年1月新乡医学院第一附属医院接诊的100例MOGAD患者进行研究,将未发生癫痫的70例作为不伴癫痫发作... 目的探讨髓鞘少突胶质细胞糖蛋白免疫球蛋白G抗体相关疾病(MOGAD)患者并发癫痫发作的临床特点及危险因素。方法前瞻性选择2022年1月至2024年1月新乡医学院第一附属医院接诊的100例MOGAD患者进行研究,将未发生癫痫的70例作为不伴癫痫发作组,将发生癫痫的30例患者作为伴癫痫发作组。记录伴癫痫发作组患者发热、脑病、视神经受累、恶心及呕吐的发生情况。比较两组患者的年龄、性别、血脑屏障损伤、头颅MRI皮质受累、前驱症状、合并风湿免疫抗体、合并其他自身免疫抗体、肌酸激酶。采用Logistic回归分析影响MOGAD患者并发癫痫发作的危险因素。结果30例MOGAD并发癫痫发作患者中发热14例,占46.67%,脑病17例,占65.67%,视神经受累8例,占26.67%,恶心及呕吐12例,占40.00%;两组患者的年龄、性别、合并风湿免疫抗体、合并其他自身免疫抗体比较差异均无统计学意义(P>0.05);伴癫痫发作组中血脑屏障损伤、头颅MRI皮质受累、前驱症状的占比及肌酸激酶水平分别为63.33%、73.33%、40.00%、(57.50±4.38)U/L,明显高于不伴癫痫发作组的34.29%、44.29%、14.29%、(45.64±2.52)U/L,差异均有统计学意义(P<0.05);Logistic回归分析结果显示,血脑屏障损伤、头颅MRI皮质受累、前驱症状、肌酸激酶均是影响MOGAD并发癫痫发作的危险因素(P<0.05)。结论MOGAD患者并发癫痫发作的临床特点以发热、脑病、恶心呕吐为主,血脑屏障损伤、头颅MRI皮质受累、前驱症状、肌酸激酶均是影响MOGAD并发癫痫发作的危险因素,临床应针对这些危险因素采取预防措施,降低癫痫的发生率。 展开更多
关键词 髓鞘少突胶质细胞糖蛋白免疫球蛋白g抗体相关疾病 癫痫 临床特点 危险因素
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g factors of nuclear low-lying states:A covariant description 被引量:5
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作者 YAO JiangMing PENG Jing +1 位作者 MENG Jie RING Peter 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第2期198-203,共6页
The g factors and spectroscopic quadrupole moments of low-lying excited states 2+1,…,81+ in 24Mg are studied in a covariant density functional theory.The wave functions are constructed by configuration mixing of axia... The g factors and spectroscopic quadrupole moments of low-lying excited states 2+1,…,81+ in 24Mg are studied in a covariant density functional theory.The wave functions are constructed by configuration mixing of axially deformed mean-field states projected on good angular momentum.The mean-field states are obtained from the constraint relativistic point-coupling model plus BCS calculations using the PC-F1 parametrization for the particle-hole channel and a density-independent delta-force for the particle-particle channel.The available experimental g factor and spectroscopic quadrupole moment of 21+ state are reproduced quite well.The angular momentum dependence of g factors and spectroscopic quadrupole moments,as well as the effects of pairing correlations are investigated. 展开更多
关键词 covariant density functional theory magnetic moment g factor spectroscopic quadrupole moment
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肥胖症患者GPR120表达的影响因素及与糖脂代谢功能的相关性分析
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作者 李纪红 郭静华 《淮海医药》 2025年第1期1-4,共4页
目的:分析肥胖症患者G蛋白偶联受体120(GPR120)表达的影响因素及与糖脂代谢功能的关联。方法:回顾性分析某院2021年5月—2023年5月收治的126例肥胖患者的临床资料,根据入院时GPR120 mRNA表达水平不同,将GPR120 mRNA≥0.5的60例患者列为... 目的:分析肥胖症患者G蛋白偶联受体120(GPR120)表达的影响因素及与糖脂代谢功能的关联。方法:回顾性分析某院2021年5月—2023年5月收治的126例肥胖患者的临床资料,根据入院时GPR120 mRNA表达水平不同,将GPR120 mRNA≥0.5的60例患者列为高表达组,GPR120 mRNA<0.5的66例患者列为低表达组。采用单因素、多因素Logistic回归方程分析肥胖患者GPR120 mRNA表达的影响因素,Spearman相关性系数分析GPR120 mRNA表达与糖脂代谢功能的相关性。结果:单因素分析显示,高表达组BMI、腰臀比(WHR)及瘦素(LP)>12.60μg/L、脂联素(ADP)<4.0 ng/L、空腹血糖(FBG)>6.0 mmol/L、空腹胰岛素(FINS)>25 pmol/mL、胰岛素抵抗指数(HOMA-IR)>2.69、总胆固醇(TC)>5.20 mmol/L、甘油三酯(TG)>1.70 mmol/L、血清甲状腺素(TT4)<155 nmol/L、脂肪游离酸(FFA)>0.9 mmol/L患者占比均高于低表达组,差异有统计学意义(P<0.05)。多因素Logistic回归分析显示,LP>12.60μg/L、ADP<4.0 ng/L、FBG>6.0 mmol/L、FINS>25 pmol/mL、HOMA-IR>2.69、TC>5.20 mmol/L、TG>1.70 mmol/L、TT4<155 nmol/L、FFA>0.9 mmol/L为肥胖患者GPR120 mRNA表达增高的危险因素。Spearman相关分析显示,GPR120 mRNA表达与LP、FBG、FINS、HOMA-IR、TC、TG、FFA水平呈正相关(r=0.253、0.254、0.255、0.261、0.255、0.254、0.257,P值均<0.05),与ADP、TT4水平呈负相关(r=-0.156、-0.158,P值均<0.05)。结论:LP、ADP、FBG、FINS、HOMA-IR、TC、TG、TT4、FFA为肥胖患者GPR120 mRNA表达增高的影响因素,GPR120 mRNA表达与LP、FBG、FINS、HOMA-IR、TC、TG、FFA水平呈正相关,与ADP、TT4水平呈负相关。 展开更多
关键词 肥胖症 g蛋白偶联受体120 糖脂代谢 影响因素 相关性分析
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