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北京师范学院学报(自然科学版) 1988年第1期 55-61页

作者：郝依群李天锡曹绛雯杨善禄康克强北京师范学院生物系

本文用统计方法对北京地区301例不同胎龄的胎儿进行了形态解剖测量研究,找出了体重与各器官发育的相互关系。

关键词：胚胎形态胎重回归分析

A storm-time ring current model(STRIM)

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Science China Technological Sciences 2024年第12期67卷 3890-3908页

作者： YU yiqun MA LongXing WEI ZiMing AN DePeng WU HaiJun LU HaoYu cao JinBin School of Space and Earth Sciences Beihang University Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information Technology

The ring current, one of the most important current systems around the Earth, intensifies during geomagnetic storms and is believed to be the main reason for large-scale magnetic field perturbations in the geospace environment. Understanding how the ring current builds up and evolves during geomagnetic storms is of great importance not only for advancing the knowledge of the Sun-Earth system but also for improving the modeling capability of predicting hazardous space weather events. Focusing on the national strategic needs in the space weather prediction, in this study, we establish a ring current model named storm time ring current model(STRIM). The STRIM comprehensively embraces key physical processes in association with ring current dynamics,including plasma source injections from the nightside plasmasheet and transport around the Earth, charge-exchange with neutral hydrogens, Coulomb collisions with thermal plasma, wave-particle interactions, field line curvature scattering, and precipitation loss down to the upper atmosphere. The electric fields needed for particle motion can be optionally taken from empirical models or self-consistently calculated, while the magnetic field configuration is obtained from Tsyganenko 2005 model. Simulation results are verified against the published literature and validated with in-situ satellite or ground-based observations and are found to have the same high-level capability and fidelity as other well-known published models. We also discuss future tasks of fostering the model's performance and potential applications.

关键词： kinetic ring current models bounce-averaged Fokker-Planck equation Earth inner magnetosphere ring current dynamics magnetic storms

Effects of polarization-reversed electromagnetic ion cyclotron waves on the ring current dynamics

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Earth and Planetary Physics 2022年第4期6卷 329-338页

作者： MingHui Zhu yiqun Yu Xing cao BinBin Ni XingBin Tian JinBin cao Vania K.Jordanova School of Space and Environment Beihang UniversityBeijing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100191China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Space Science and Application Los Alamos National LaboratoryLos Alamos87545New MexicoUSA

Electromagnetic ion cyclotron(EMIC)waves are widely believed to play an important role in influencing the radiation belt and ring current *** studies have investigated the effects or characteristics of EMIC waves by assuming their left-handed ***,recent studies have found that the reversal of polarization,which occurs at higher latitudes along the wave propagation path,can change the wave-induced pitch angle diffusion *** such a polarization reversal can influence the global ring current dynamics remains *** this study,we investigate the ring current dynamics and proton precipitation loss in association with polarization-reversed EMIC waves by using the ring current-atmosphere interactions model(RAM).The results indicate that the polarization reversal of H-band EMIC waves can truly decrease the scattering rates of protons of 10 to 50 keV or>100 keV in comparison with the scenario in which the EMIC waves are considered purely left-handed ***,the global ring current intensity and proton precipitation may be slightly affected by the polarization reversal,especially during prestorm time and the recovery phase,but the effects are not large during the main *** is probably because the H-band EMIC waves contribute to the proton scattering loss primarily at E<10 keV,an energy range that is not strongly affected by the polarization reversal.

关键词： electromagnetic ion cyclotron waves polarization reversal ring current

STN-DBS对纹状体细胞外液牛磺酸含量的影响

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中华神经外科疾病研究杂志 2010年第3期9卷 232-235页

作者：曹依群周晓平刘汉华赵旭东姜秀峰第二军医大学长海医院神经外科上海200433

目的探讨丘脑底核脑深部电刺激对猴帕金森病模型纹状体区细胞外液中牛磺酸含量的影响。方法猴偏侧帕金森病模型,在患侧丘脑底核植入人用脑深部刺激电极,同期猴背部皮下植入脉冲发生器和皮下导线,通过测试后给予有效高频电刺激,利用微透... 详细信息

目的探讨丘脑底核脑深部电刺激对猴帕金森病模型纹状体区细胞外液中牛磺酸含量的影响。方法猴偏侧帕金森病模型,在患侧丘脑底核植入人用脑深部刺激电极,同期猴背部皮下植入脉冲发生器和皮下导线,通过测试后给予有效高频电刺激,利用微透析技术分别在打开脉冲发生器前和开机后的不同时间点在双侧壳核、尾状核头部细胞外液进行取样。对取样标本应用高效液相色谱荧光法检测其中牛磺酸的含量变化。结果电极侧壳核和尾状核的牛磺酸含量在开机后较开机前明显增加(P<0.05)。结论丘脑底核脑深部刺激后可引起纹状体区细胞外液中牛磺酸的含量明显升高,这可能是丘脑底核脑深部电刺激的作用机制之一。

关键词：丘脑底核脑深部电刺激微透析牛磺酸

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经蝶窦手术治疗巨大垂体腺瘤

中华神经外科疾病研究杂志 2010年第3期9卷 200-202页

作者：岳志健曹依群王来兴刘建民洪波方亦斌邹宇辉第二军医大学长海医院神经外科上海2004331

目的探讨经蝶窦手术治疗巨大垂体腺瘤的临床效果。方法从2005年3月至2008年12月，采用经蝶窦分次手术治疗直径大于4cm的巨大垂体腺瘤46例，其中无功能腺瘤24例，泌乳素腺瘤9例，生长激素瘤10例，促肾上腺皮质激素腺瘤1例，混合性腺瘤2... 详细信息

目的探讨经蝶窦手术治疗巨大垂体腺瘤的临床效果。方法从2005年3月至2008年12月，采用经蝶窦分次手术治疗直径大于4cm的巨大垂体腺瘤46例，其中无功能腺瘤24例，泌乳素腺瘤9例，生长激素瘤10例，促肾上腺皮质激素腺瘤1例，混合性腺瘤2例。结果本组患者1次手术31例，2次手术12例，3次手术3例。分次手术间隔为6～8W。全切除26例，次全切除20例。术后并发垂体功能低下2例，脑脊液漏2例，术后肢体偏瘫1例。无死亡病例。l例在手术后2年肿瘤复发。结论经蝶窦手术能有效治疗巨大垂体腺瘤。分次经蝶窦手术能有效提高手术全切除率并减少术后并发症。

关键词：垂体腺瘤巨大经蝶窦手术

Effects of a dipole-like crustal field on solar wind interaction with Mars

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Earth and Planetary Physics 2020年第1期4卷 23-31页

作者： ShiBang Li HaoYu Lu Jun Cui yiqun Yu Christian Mazelle Yun Li JinBin cao School of Space and Environment Beihang UniversityBeijing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100191China School of Atmospheric Sciences Sun Yat-Sen UniversityZhuhai Guangdong 519082China CNRS Institute de Recherche en Astrophysique et PlanétologieToulouseFrance

A three-dimensional four species multi-fluid magnetohydrodynamic (MHD) model was constructed to simulate the solar wind global interaction with Mars. The model was augmented to consider production and loss of the significant ion species in the Martian ionosphere, i.e., H^+, O2^+, O^+, CO^+2, associated with chemical reactions among all species. An ideal dipole-like local crustal field model was used to simplify the empirically measured Martian crustal field. Results of this simulation suggest that the magnetic pile-up region (MPR) and the velocity profile in the meridian plane are asymmetric, which is due to the nature of the multi-fluid model to decouple individual ion velocity resulting in occurrence of plume flow in the northern Martian magnetotail. In the presence of dipole magnetic field model, boundary layers, such as bow shock (BS) and magnetic pile-up boundary (MPB), become protuberant. Moreover, the crustal field has an inhibiting effect on the flux of ions escaping from Mars, an effect that occurs primarily in the region between the terminator (SZA 90°) and the Sun Mars line of the magnetotail (SZA 180°), partially around the terminator region. In contrast, near the tailward central line the crustal field has no significant impact on the escaping flux.

关键词： solar wind interaction with Mars global MHD simulation crustal field escape flux

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体外人脑胶质瘤电阻抗特性及等效电路

北京生物医学工程 2014年第4期33卷 387-392,438页

作者：金定毅钱晋武沈林勇张煜辉毛光金曹依群上海大学机电工程与自动化学院上海200072 第二军医大学第一附属医院神经外科上海200433

目的研究人脑胶质瘤的电阻抗特性并建立其等效电路,可为进一步区分人脑胶质瘤和正常脑组织的阻抗特性差异提供依据。方法利用英国Solartron公司的阻抗分析仪(1260),采用四端法,在10Hz^10 MHz范围内,对4例体外人胶质瘤组织进行电阻抗测... 详细信息

目的研究人脑胶质瘤的电阻抗特性并建立其等效电路,可为进一步区分人脑胶质瘤和正常脑组织的阻抗特性差异提供依据。方法利用英国Solartron公司的阻抗分析仪(1260),采用四端法,在10Hz^10 MHz范围内,对4例体外人胶质瘤组织进行电阻抗测量。通过分析其频率特性并结合已有的人脑组织的等效电路,建立了体外胶质瘤的等效电路,利用阻抗分析软件Z-VIEW对其进行仿真。结果体外人脑胶质瘤的阻抗模值在10 Hz^10 MHz范围内随频率的增大而下降,相位角在该范围内随频率的增大而增大。体外人脑胶质瘤组织在10 kHz^10 MHz范围内电阻抗实部比较稳定,其中在10Hz^10 kHz范围内,实部随频率的增大而减小。电阻抗虚部在20 kHz^10 MHz范围内较稳定,而在10Hz^20 kHz范围内,虚部随频率增大而增大。样本的等效电路仿真曲线与实际曲线相比较,等效电路模型能较好地反映体外人脑胶质瘤的电阻抗特性。结论体外人脑胶质瘤与已知的正常脑组织的电阻抗特性及等效电路差别明显,这为探索生物电阻抗技术应用于区别胶质瘤与正常脑组织的临床应用提供了研究基础。

关键词：人脑胶质瘤电阻抗等效电路

Top-down评估黄曲霉毒素B1测量不确定度

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农产品加工 2020年第2期 51-52页

作者：曹轶群黎杰蒙韦玲蒋才斌缪璐陀雄信干宁军广西壮族自治区产品质量检验研究院

采用自上而下(top-down)对食用花生油中黄曲霉毒素B1(AFB_1)的不确定度进行评定,数据主要来源于实验室平时检测数据。不确定度通过期间精密度不确定度分量和偏倚不确定度分量进行合成,获得实验室黄曲霉毒素B_1(AFB1)的扩展不确定度值为6... 详细信息

采用自上而下(top-down)对食用花生油中黄曲霉毒素B1(AFB_1)的不确定度进行评定,数据主要来源于实验室平时检测数据。不确定度通过期间精密度不确定度分量和偏倚不确定度分量进行合成,获得实验室黄曲霉毒素B_1(AFB1)的扩展不确定度值为6.5%(k=2)。该方法避免了复杂的分量查找计算,简化了不确定度的评定。

关键词：黄曲霉毒素B_1(AFB_1) 测量不确定度自上而下(top-down)

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食用花生油品质状况检测

农产品加工 2020年第3期 60-61,64页

作者：曹轶群蒋才斌周寿勇陆莉莉黎杰蒙韦玲广西壮族自治区产品质量检验研究院

食用花生油是日常生活中量大面广的消费食品,为评估食用花生油品质,对3项主要指标酸价、过氧化值及黄曲霉毒素B1(AFB1)进行了检测。结果表明,440批次样品的不合格率为32%,主要不合格项目为AFB1,不合格样品主要来源为小油坊。食用花生油... 详细信息

食用花生油是日常生活中量大面广的消费食品,为评估食用花生油品质,对3项主要指标酸价、过氧化值及黄曲霉毒素B1(AFB1)进行了检测。结果表明,440批次样品的不合格率为32%,主要不合格项目为AFB1,不合格样品主要来源为小油坊。食用花生油仍存在食品安全隐患,为安全起见,建议消费者最好购买品牌产品。

关键词：食用花生油黄曲霉毒素B1(AFB1) 酸价过氧化值

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假瘤样脱髓鞘病变—脊髓手术的误区

中华神经外科疾病研究杂志 2014年第1期13卷 51-54页

作者：李亚楠曹依群戴冬伟韩国胜张煜辉王来兴岳志健第二军医大学长海医院神经外科上海200433

目的脊髓的假瘤样脱髓鞘病变(TDLs)与肿瘤之间的鉴别非常困难。由于两种疾病的治疗方法不同,对于脊髓TDLs的误诊往往导致了严重的后果。方法对5例收治的脊髓TDLs的患者进行了总结,从临床资料、影像学表现、治疗方法及预后进行归纳分析... 详细信息

目的脊髓的假瘤样脱髓鞘病变(TDLs)与肿瘤之间的鉴别非常困难。由于两种疾病的治疗方法不同,对于脊髓TDLs的误诊往往导致了严重的后果。方法对5例收治的脊髓TDLs的患者进行了总结,从临床资料、影像学表现、治疗方法及预后进行归纳分析。结果患者的平均年龄为50.4岁;主要临床表现包括:肢体肌力下降、疼痛及麻木等;脊柱所有节段均可能受累及;影像学表现包括:占位效应、病灶周边水肿、不规则环形强化等;1例接受病灶活检,另外4例接受病灶手术切除;术中冰冻病理无法正确判断病理类型;在病理结果证实为TDLs后,所有患者均接受了激素治疗;所有患者对激素治疗反应良好,随访中未见病灶复发及症状加重。结论由于不同的诊断会直接导致不同的治疗手段,因此对于脊髓内占位性病变的诊断及治疗需要谨慎处理:术前应尽量完善各种辅助检查;术中以保留正常脊髓功能为主,不追求病灶全切除,并可进行活检;在病理分析遇到困难时应寻求神经病理学帮助;对于术前高度怀疑为脊髓TDLs的患者可考虑给予诊断性激素治疗,但需从临床及影像学方面密切动态观察。

关键词：瘤样脱髓鞘病变脊髓活检激素治疗肿瘤