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Derivation of moment Equations for the Theoretical Description of Electrons in Nonthermal Plasmas

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Advances in Pure mathematics 2013年第3期3卷 343-352页

作者： markus m. becker Detlef Loffhagen Leibniz Institute for Plasma Science and Technology Greifswald Germany

The derivation of moment equations for the theoretical description of electrons is of interest for modelling of gas discharge plasmas and semiconductor devices. Usually, certain artificial closure assumptions are applied in order to derive a closed system of moment equations from the electron Boltzmann equation. Here, a novel four-moment model for the description of electrons in nonthermal plasmas is derived by an expansion of the electron velocity distribution function in Legendre polynomials. The proposed system of partial differential equations is consistently closed by definition of transport coefficients that are determined by solving the electron Boltzmann equation and are then used in the fluid calculations as function of the mean electron energy. It is shown that the four-moment model can be simplified to a new drift-diffusion approximation for electrons without loss of accuracy, if the characteristic frequency of the electric field alteration in the discharge is small in comparison with the momentum dissipation frequency of the electrons. Results obtained by the proposed fluid models are compared to those of a conventional drift-diffusion approximation as well as to kinetic results using the example of low pressure argon plasmas. It is shown that the results provided by the new approaches are in good agreement with kinetic results and strongly improve the accuracy of fluid descriptions of gas discharges.

关键词： moment Equations Plasma modelling Electron Transport

Cryopreservation for delayed circulating tumor cell isolation is a valid strategy for prognostic association of circulating tumor cells in gastroesophageal cancer

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World Journal of Gastroenterology 2018年第7期24卷 810-818页

作者： Daniel Brungs David Lynch Alison WS Luk Elahe minaei marie Ranson morteza Aghmesheh Kara L Vine martin Carolan mouhannad Jaber Paul de Souza Therese m becker Illawarra Health and medical Research Institute University of WollongongWollongong 2500Australia School of Biological Sciences University of WollongongWollongong 2500Australia Illawarra Cancer Centre Wollongong HospitalWollongong 2500Australia CONCERT-Translational Cancer Research Centre New South Wales 2000Australia Centre for Circulating Tumor Cell Diagnostics and Research Ingham Institute for Applied Medical ResearchLiverpool HospitalSydney 2170Australia School of medicine University of Western SydneySydney 2170Australia South Western medical School University of New South WalesSydney 2170Australia

AIm To demonstrate the feasibility of cryopreservation of peripheral blood mononuclear cells(PBmCs) for prognostic circulating tumor cell(CTC) detection in gastroesophageal *** Using 7.5 m L blood samples collected in EDTA tubes from patients with gastroesopheagal adenocarcinoma, CTCs were isolated by epithelial cell adhesion molecule based immunomagnetic capture using the Iso Flux platform. Paired specimens taken during the same blood draw(n = 15) were used to compare number of CTCs isolated from fresh and cryopreserved PBmCs. Blood samples were processed within 24 h to recover the PBmC fraction, with PBmCs used for fresh analysis immediately processed for CTC isolation. Cryopreservation of PBmCs lasted from 2 wk to 25.2 mo(median 14.6 mo). CTCs isolated from pre-treatment cryopreserved PBmCs(n = 43) were examined for associations with clinicopathological variables and survival *** While there was a significant trend to a decrease in CTC numbers associated with cryopreserved specimens(mean number of CTCs 34.4 vs 51.5, P = 0.04), this was predominately in samples with a total CTC count of > 50, with low CTC count samples less affected(P = 0.06). There was no significant association between the duration of cryopreservation and number of CTCs. In cryopreserved PBmCs from patient samples prior to treatment, a high CTC count(> 17) was associated with poorer overall survival(OS)(n = 43, HR = 4.4, 95%CI: 1.7-11.7, P = 0.0013). In multivariate analysis, after controlling for sex, age, stage, ECOG performance status, and primary tumor location, a high CTC count remained significantly associated with a poorer OS(HR = 3.7, 95%CI: 1.2-12.4, P = 0.03). CONCLUSION PBmC cryopreservation for delayed CTC isolation is a valid strategy to assist with sample collection, transporting and processing.

关键词： Cryopreservation Circulating tumor cells Liquid biopsy Gastroesophageal cancer Gastric cancer

A Guide to Biomolecular Simulations 1

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Superior biocompatibility and comparable osteoinductive properties: Sodium-reduced fluoride-containing bioactive glass belonging to the CaO–mgO–SiO2 system as a promising alternative to 45S5 bioactive glass

丛书名： Focus on Structural Biology

2006年

作者： Oren m. becker martin Karplus (auth.)

来源：畅想之星图书光盘版（南... 评论

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Bioactive materials 2020年第1期5卷 55-65页

作者： S.I.Schmitz B.Widholz C.Essers m.becker D.U.Tulyaganov A.moghaddam I.Gonzalo de Juan F.Westhauser Center of Orthopedics Traumatology and Spinal Cord InjuryHeidelberg University HospitalSchlierbacher Landstraße 200a69118HeidelbergGermany Disperse Solid materials Technical University DarmstadtOtto-Berndt-Straße 364287DarmstadtGermany Department of Natural-mathematical Sciences Turin Polytechnic University in Tashkent17 Small Ring Street100095TashkentUzbekistan ATORG-Aschaffenburg Trauma and Orthopedic Research Group Center for Trauma SurgeryOrthopedicsand Sports MedicineKlinikum Aschaffenburg-AlzenauAm Hasenkopf 163739AschaffenburgGermany

Bioactive glasses(BGs)are promising bone substitute ***,under certain circumstances BGs such as the well-known 45S5 Bioglass®(composition in wt%:45.0 SiO2,24.5 Na2O,24.5 CaO,6.0 P2O5)act cytotoxic due to a strong increase in pH caused by a burst release of sodium ions.A potential alternative is a sodiumreduced fluoride-containing BG belonging to the CaO–mgO–SiO2 system,namely BG1d-BG(composition in wt%:46.1 SiO2,28.7 CaO,8.8 mgO,6.2 P2O5,5.7 CaF2,4.5 Na2O),that has already been evaluated in-vitro,in-vivo and in preliminary clinical *** further application,however,BG1d-BG should be compared to the benchmark amongst BGs,the 45S5 Bioglass®composition,to classify its effect on cell viability,proliferation and osteogenic differentiation of human mesenchymal stem cells(mSCs).Therefore,in this study,the biocompatibility and osteogenic potential of both BGs were investigated in an indirect and direct culture setting to assess the effect of the ionic dissolution products and the BGs’physical presence on the *** results indicated an advantage of BG1d-BG over 45S5 Bioglass®regarding cell viability and *** BGs induced an earlier onset of osteogenic differentiation and accelerated the expression of late osteoblast marker genes compared to the control *** conclusion,BG1d-BG is an attractive candidate for further experimental *** basic mechanisms behind the different impact on cell behavior should be assessed in further detail,*** further alteration of the BG compositions.

关键词： 45S5 Bioglass® Sodium-reduced bioactive glass Fluoride-containing bioactive glass Bone tissue engineering Human mesenchymal stromal cells

Sexual assaults in therapeutic relationships: prevalence, risk factors and consequences

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Health 2010年第9期2卷 1018-1026页

作者： C. Eichenberg m. becker-Fischer G. Fischer 不详

A law has been passed in Germany (paragraph 174c StGB), which prohibits therapists from having sexual contact with their patients. This provides the background for a follow-up survey to the previous study completed by becker- Fischer and Fischer in 1995. The results of this survey are discussed here on the basis of the current status of research concerning preva- lence and risk factors of sexual assaults in therapeutic relationships. The focus of the re- search lies in determining the specific condi- tions of sexual assaults in psychotherapy and psychiatry, risk variables of the therapists and patients, the effects it has on the patients as well as the legal consequences it results in. To en- sure the comparability of the data, an online version of the Questionnaire about Sexual Con- tacts in Psychotherapy and Psychiatry (SKPP;becker-Fischer, Fischer & Jerouschek) was cre- ated and a survey of N = 77 affected patients was conducted. The majority of the participants in the study reported a serious decline in their overall well being following the incident. How- ever only very few undertook legal steps - only in three cases did it come to a legal procedure. The assumption that sexual contacts in psy- chotherapy result in extremely damaging con- sequences to patients, was affirmed. Despite the changed legal situation, therapists in Ger- many are still not held legally responsible more often than they were 10 years ago. Based on these results a more intensive education of the patients concerning their legal rights is recom- mended.

关键词： Sexual Assaults Psychotherapy Patient Abuse Professionale misconduct

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ET型潮汐重力仪的改进

测绘学报 1990年第3期19卷 229-235页

作者： m.becker E.Groten 陶国祥许厚泽联邦德国达姆施达特大学物理大地测量研究所中国科学院测量与地球物理研究所

从1983年Harrison和Sato应用电子反馈系统到Lacoste-Romberg D型和G型重力仪以来，世界上几个国家都在改造G型、D型和ET型重力仪。中国科学院测量与地球物理研究所ET型重力仪属于老式机械反馈式重力仪，记录只能采用模拟记录，资料处理... 详细信息

从1983年Harrison和Sato应用电子反馈系统到Lacoste-Romberg D型和G型重力仪以来，世界上几个国家都在改造G型、D型和ET型重力仪。中国科学院测量与地球物理研究所ET型重力仪属于老式机械反馈式重力仪，记录只能采用模拟记录，资料处理结果精度不高，为了进一步提高仪器的性能，今年初，中国科学院测量与地球物理研究所与西德Darmstadt大学物理大地测量研究所共同采用西德的SRW方法将ET-20重力仪改为静电反馈型重力仪。静电反馈型的主要优点是，反馈灵敏度与倾斜无关，消除了弹簧的迟滞影响，使传递函数变得简单，重力仪的附件体积大大减小，现在已采用了数字记录系统，取得了较好的初步结果。

关键词：潮汐重力仪 ET型

利用高精度重力测量监测地壳运动的方法和经验

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地震地质译丛 1995年第5期17卷 55-60页

作者： E.Groten m.becker 沈

1.引言监测现代地壳运动的大地测量技术,自从板块构造中的大规模构造现象,可以用精确的大地测量方法,如极长基线干涉测量(VLBI)、地理定位系统(GPS)、局部大地测量法等,变得越来越明显时,就在'零频率地震学'中得到越来越多的重视。尽管... 详细信息

1.引言监测现代地壳运动的大地测量技术,自从板块构造中的大规模构造现象,可以用精确的大地测量方法,如极长基线干涉测量(VLBI)、地理定位系统(GPS)、局部大地测量法等,变得越来越明显时,就在'零频率地震学'中得到越来越多的重视。尽管如此,重力测量技术以及探索多震区的地形法,已在半个世纪前就开始利用了。利用高精度大地重力测量,比地形特征更细小的现象,如布格异常等,都可以利用。因此,与地震有关的水位变化,及现代地壳运动事件,可以通过重复观测和连续监测而测定出。如果我们考虑干涉合成口径雷达(SAR)卫星技术,即利用地球资源卫星(ERS-1)揭示空间分辨率为±2.8cm。

关键词：地壳运动重力测量监测法

中国和英国子宫内膜异位症患者的发病相关因素分析

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南方医科大学学报 2022年第1期42卷 137-142页

作者：聂伟哲李舒婷 Krina T.Zondervan Christian m.becker 郭逸男宗利丽广州中医药大学第一临床医学院广东广州510405 广州中医药大学第一附属医院国家区域(华南区)中医妇科诊疗中心广东广州510405 Oxford Endometriosis CaRe Centre Nuffield Department of Women's and Reproductive HealthUniversity of OxfordOxford UK OX39DU Wellcome Centre for Human Genetics University of OxfordOxford UK OX39DU 西安市中医院妇科陕西西安710021

目的研究子宫内膜异位症发病的相关因素及其在中国和英国患者之间可能的差异。方法采用病例对照研究方法,选取英国牛津John Radcliffe Hospital收治的子宫内膜异位症患者387例和非子宫内膜异位症患者199例、广州中医药大学第一附属医院... 详细信息

目的研究子宫内膜异位症发病的相关因素及其在中国和英国患者之间可能的差异。方法采用病例对照研究方法,选取英国牛津John Radcliffe Hospital收治的子宫内膜异位症患者387例和非子宫内膜异位症患者199例、广州中医药大学第一附属医院收治的子宫内膜异位症患者101例和非子宫内膜异位症患者50例分别为病例组和对照组。通过标准化的WERF EPHect调查问卷,收集4组人群的身高、体质量、体质量指数、婚姻状况、工作状况、月经情况、生育情况、手术原因等临床资料并进行统计分析。结果多因素Logistic回归分析结果显示,英国患者中体质量指数、因痛经进行手术、怀孕史、既往子宫内膜异位症手术次数、工作情况等均与子宫内膜异位症的发生相关(P<0.05),而中国患者中痛经史与子宫内膜异位症的发生相关(P<0.05)。结论痛经可能是中国和英国子宫内膜异位症患者最主要的相关因素;同时,子宫内膜异位症发生的相关因素在中国和英国患者之间可能存在差异。

关键词：子宫内膜异位症中国人群英国人群相关因素差异性

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人造冠的外形、边缘位置及桥体形式的新学说

国际口腔医学杂志 1982年第3期 41-43页

作者： Curtis m becker ,闻玉平

修复治疗的基本目的之一为建立一个生理性的牙周环境,以及便于维持牙周健康。人造冠的外形、边缘位置及桥体的形式均能影响牙周的健康。本文复习了有关这三方面的最新学说。冠的外形:全冠及部份冠的外形对建立一个较理想的牙周环境是起... 详细信息

修复治疗的基本目的之一为建立一个生理性的牙周环境,以及便于维持牙周健康。人造冠的外形、边缘位置及桥体的形式均能影响牙周的健康。本文复习了有关这三方面的最新学说。冠的外形:全冠及部份冠的外形对建立一个较理想的牙周环境是起主要作用的。冠外形的三个主要学说为:1.牙龈保护学说;2.肌肉作用学说;3.便于口腔清洁学说。牙龈保护学说:主张修复体设计的形态要具有保护牙龈免遭机械性刺激的作用。本观点虽缺乏科学依据,但在牙医学领域内持续很久,这主要是凭借经验而论的。Wheeler氏认为“由于牙龈缺乏保护而有根尖退缩的倾向,嗣后将产生有害的影响”。一些牙科医师及技术室人员认为既然轻微刺激对

关键词：桥体学说人造冠菌斑楔状隙邻面食物嵌塞修复体边缘位置