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Enhancements to modified Chebyshev-Picard Iteration Efficiency for Perturbed Orbit Propagation

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Computer modeling in Engineering & Sciences 2016年第1期111卷 29-64页

作者： B.macomber A.B.Probe R.Woollands j.Read j.L.junkins Texas A&m University College StationTXUSA.

modified Chebyshev Picard Iteration is an iterative numerical method for solving linear or non-linear ordinary differential *** a serial computational environment the method has been shown to compete with,or outperform,current state of practice numerical *** paper presents several improvements to the basic method,designed to further increase the computational efficiency of solving the equations of perturbed orbit propagation.

关键词： Astrodynamics Orbit Propagation Cheybshev Polynomials Picard Iteration.

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冠状动脉疾病彩色图谱

2001年

作者：（英）m.j.戴维斯（m.j.Davies）徐晓雷等译

本书分为四大部分：冠状动脉解剖、动脉粥样硬化的演变过程、急性缺血性综合征及冠心病、稳定型心绞痛。全书共收集了161幅彩色图像，直观地展示了尸检中所看到的冠状动脉的宏观表现及各种重要疾病。

ISBN: (纸本)7543311941

关键词：冠心病

来源：汇雅图书（南通市图书馆... 评论

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计算机辅助三维勘探设计

国外油气勘探 1995年第4期7卷 487-494页

作者： j.m.Galbraith 田文辉石油物探局地质调查二处

三维采集要求认真的设计。接收线和炮线的布设必须根据所要求的地质目标而定。到目前为止,已经出现了多种设计软件,它们可以协助地球物理工作者完成这项工作。本文将讨论三维勘探设计的基本要点,并以实例说明一些具体方法。

关键词：三维勘探 CAD 油气勘探地球物理勘探

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锰—1988年回顾与展望

中国锰业 1989年第1期 60-63页

作者： m·j·Carmichael 周日新

粗钢所消耗的锰占整个开采量的90％以上,因而锰工业兴旺与否主要取决于全世界粗钢的市场状况。1987年第一季度,国际钢铁学会报道各国租钢产量下降6。5％,因而在那段期间,锰的销售额实际上没有增加。西欧受影响最为严重。这种现象给三、四月

关键词：锰矿石南非厂家布罗肯希尔黑色金属矿石非洲冶金工业钢铁工业矿石生产重有色金属合金锰合金高品位矿石

CYP24A1 inhibition facilitates the anti-tumor effect of vitamin D3 on colorectal cancer cells

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World journal of Gastroenterology 2013年第17期19卷 2621-2628页

作者： jános P Kósa Péter Horváth jános Wlfling Dóra Kovács Bernadett Balla Péter mátyus Evelin Horváth Gábor Speer István Takács Zsolt Nagy Henrik Horváth Péter Lakatos 1 st Department of Internal medicine Semmelweis University Department of Organic Chemistry University of Szeged Department of Organic Chemistry Semmelweis University

AIm:The effects of vitamin D3 have been investigated on various tumors, including colorectal cancer (CRC). 25-hydroxyvitamin-D3-24-hydroxylase (CYP24A1), the enzyme that inactivates the active vitamin D3 metabolite 1,25-dihydroxyvitamin D3 (1,25-D3), is considered to be the main enzyme determining the biological halflife of 1,25-D3. During colorectal carcinogenesis, the expression and concentration of CYP24A1 increases significantly, suggesting that this phenomenon could be responsible for the proposed efficacy of 1,25-D3 in the treatment of CRC. The aim of this study was to investigate the anti-tumor effects of vitamin D3 on the human CRC cell line Caco-2 after inhibition of the cytochrome P450 component of CYP24A1 activity. mETHODS:We examined the expression of CYP24A1 mRNA and the effects of 1,25-D3 on the cell line Caco-2 after inhibition of CYP24A1. Cell viability and proliferation were determined by means of sulforhodamine-B staining and bromodeoxyuridine incorporation, respectively, while cytotoxicity was estimated via the lactate dehydrogenase content of the cell culture supernatant. CYP24A1 expression was measured by realtime reverse transcription polymerase chain reaction. A number of tetralone compounds were synthesized to investigate their CP24A1 inhibitory activity. RESULTS:In response to 1,25-D3, CYP24A1 mRNA expression was enhanced significantly, in a time- and dose-dependent manner. Caco-2 cell viability and proliferation were not influenced by the administration of 1,25-D3 alone, but were markedly reduced by coadministration of 1,25-D3 and KD-35, a CYP24A1-inhibiting tetralone. Our data suggest that the mechanism of action of co-administered KD-35 and 1,25-D3 does not involve a direct cytotoxic effect, but rather the inhibition of cell proliferation. CONCLUSION:These findings demonstrate that the selective inhibition of CYP24A1 by compounds such as KD-35 may be a new approach for enhancement of the anti-tumor effect of 1,25-D3 on CRC.

关键词： Colorectal cancer CYP24A1 inhibition Vitamin D3 Tetralone derivatives Caco-2 cell culture

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牛骨移植及牙种植体植入的实验研究

中华口腔医学杂志 1998年第2期33卷 76-78页

作者：赵怡芳 j.m.Symington R.D.Listrom 湖北医科大学口腔医学院加拿大多伦多大学牙科系口腔颌面外科

目的探讨牛骨块在牙种植领域应用的可能性。方法将２０块牛骨外置移植于兔胫骨干骺端，同时植入牙种植体固定骨块。术后按计划给动物注射三种荧光素，并通过组织学和组织测量学方法评价新骨形成。结果荧光素标记的新骨逐渐替代移植骨的... 详细信息

目的探讨牛骨块在牙种植领域应用的可能性。方法将２０块牛骨外置移植于兔胫骨干骺端，同时植入牙种植体固定骨块。术后按计划给动物注射三种荧光素，并通过组织学和组织测量学方法评价新骨形成。结果荧光素标记的新骨逐渐替代移植骨的松质骨和部分皮质骨，实验结束时新骨已达牙种植体肩台平面。实验８４天，４个上位螺纹平面的骨面积明显高于２１天的骨面积。平均矿物沉积率为１．９０μｍ／ｄ～２．７５μｍ／ｄ。结论牛骨外置移植结合螺钉型牙种植体植入可增加受区骨量。

关键词：种植体牙植人体异种移植牛骨

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电气化高速铁路接触网微风振动特性

西南交通大学学报 2015年第1期50卷 1-6页

作者：刘志刚宋洋刘煜铖西南交通大学电气工程学院四川成都610031

为评估接触线微风振动现象对接触网运营的的影响,计算不同风速下的接触线风振幅值,基于模态分解法推导了电气化高速铁路接触网垂直方向上的微风振动方程.首先求解出接触网的固有频率与振型,然后推导作用在接触线上的微风激振力,最后计... 详细信息

为评估接触线微风振动现象对接触网运营的的影响,计算不同风速下的接触线风振幅值,基于模态分解法推导了电气化高速铁路接触网垂直方向上的微风振动方程.首先求解出接触网的固有频率与振型,然后推导作用在接触线上的微风激振力,最后计算接触网在发生微风振动时,不同风速作用下各频率对应的振幅.分析风速、频率与振幅的对应关系.结果表明,接触线微风振动的最大幅值一般在1 mm以内,不会产生输电线微风振动时类似的振动幅值;文中算例接触线微风振动最大幅值出现在风速为1.44 m/s时,仅有0.96 mm,不会对电气化铁路的实际运营造成显著影响.

关键词：电气化铁路接触网微风振动固有频率

Distinct transcriptomic landscapes of cutaneous basal cell carcinomas and squamous cell carcinomas

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Genes & Diseases 2021年第2期8卷 181-192页

作者： jun Wan Hongji Dai Xiaoli Zhang Sheng liu Yuan Lin Ally-Khan Somani jingwu Xie jiali Han Department of medical and molecular Genetics Indiana University School of MedicineIndianapolisIN46202USA Center for Computational Biology and Bioinformatics Indiana University School of MedicineIndianapolisIN46202USA School of Informatics and Computing Indiana University e Purdue University at IndianapolisIndianapolisIN46202USA Department of Epidemiology and Biostatistics Key Laboratory of Cancer Prevention and TherapyNational Clinical Research Center of CancerTianjin Medical University Cancer Institute and HospitalTianjin300000PR China Wells Center for Pediatric Research Department of PediatricsIndiana University School of MedicineIndianapolisIN46202USA melvin and Bren Simon Cancer Center Indiana University School of MedicineIndianapolisIN46202USA Department of Epidemiology Richard M.Fairbanks School of Public HealthIndiana UniversityIndianapolisIN46202USA Dermatologic Surgery&Cutaneous Oncology Division Department of DermatologyIndiana University School of MedicineIndianapolisIN46202USA

The majority of non-melanoma skin cancer(NmSC)is cutaneous basal cell carcinoma(BCC)or squamous cell carcinoma(SCC),which are also called keratinocyte carcinomas,as both of them originate from *** incidence of keratinocyte carcinomas is over 5 million per year in the US,three-fold higher than the total incidence of all other types of cancer *** there are several reports on gene expression profiling of BCC and SCC,there are significant variations in the reported gene expression changes in different *** reason is that tumor-adjacent normal skin specimens were not included in many studies as matched ***,while numerous studies of skin stem cells in mouse models have been reported,their relevance to human skin cancer remains *** this report,we analyzed gene expression profiles of paired specimens of keratinocyte carcinomas with their matched normal skin tissues as the *** several novel findings,we discovered a significant number of zinc finger encoding genes up-regulated in human *** BCC,a novel link was found between hedgehog signaling,Wnt signaling,and the *** the SCC cancerstem-cell gene signature is shared between human and mouse SCCs,the hair follicle stem-cell signature of mice was not highly represented in human *** gene expression(DEG)in human BCC shares gene signature with both bulge and epidermal stem *** have also determined that human BCCs and SCCs have distinct gene expression patterns,and some of them are not fully reflected in current mouse models.

关键词： Basal cell carcinoma Gli1 Hedgehog signaling PTCH1 Squamous cell carcinoma

Spatiotemporal analysis of elastic and inelastic deformations in roof-rocks from seismological observations

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International journal of mining Science and Technology 2021年第2期31卷 241-251页

作者： maciej jmendecki RafałPakosz Łukasz Wojtecki Wacław mZuberek Faculty of Environmental Sciences the University of Silesia in Katowice41-200 SosnowiecPoland Polish mining Group 40-039 KatowicePoland Central mining Institute 40-166 KatowicePoland

The spatiotemporal analysis of seismic zones characterised by the scattering and accumulation of strain energy in the roof-rocks of the excavated longwall panel where inelastic or elastic deformations occurred during hard coal seam mining is *** studied longwall panel was designed to utilize the effect of partial stress relaxation caused by the earlier extraction of the coal seams located above.A full seismic moment tensor and spectral source parameter analyses were used to obtain information about the degree of inelastic and elastic coseismic *** study also showed that these deformation changes correspond to variation in the Benioff strain release ***,analyses of deformation zones were compared with the relationship between radiated energy and the excavated volume of rocks per *** concept of balanced seismic energy release assumed the exponential increase of released seismic energy with the increase in the volume of excavated *** between the observed and predicted radiated energies indicated that strain energy in selected zones in the rock mass was either scattered if the prediction was overestimated,or accumulated if ***,the study showed that elastic deformation in one zone can lead to inelastic deformation in the same zone.

关键词： mining seismicity Seismic source volume Apparent volume Hard coal mine Longwall mining Benioff strain