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Mechanical constraints in tumor guide emergent spatial patterns of glioblastoma cancer stem cells

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Mechanobiology in Medicine 2024年第1期2卷 67-76页

作者： Ngoc Luu Shuhao Zhang raymond H.W.Lam Weiqiang Chen Department of Biomedical Engineering New York UniversityBrooklynNYUSA Department of Mechanical and Aerospace Engineering New York UniversityBrooklynNYUSA Department of Biomedical Engineering City University of Hong KongHong Kong SARChina Centre for Biosystems Neuroscienceand NanotechnologyCity University of Hong KongHong Kong SARChina City University of Hong Kong Shenzhen Research Institute ShenzhenChina Laura and Isaac Perlmutter Cancer Center NYU Langone HealthNew YorkUSA

The mechanical constraints in the overcrowding glioblastoma(GBM)microenvironment have been implicated in the regulation of tumor heterogeneity and disease ***,such mechanical cues can alter cellular DNA transcription and give rise to a subpopulation of tumor cells called cancer stem cells(CSCs).These CSCs with stem-like properties are critical drivers of tumorigenesis,metastasis,and treatment ***,the biophysical and molecular machinery underlying the emergence of CSCs in tumor remained *** work employed a two-dimensional micropatterned multicellular model to examine the impact of mechanical constraints arisen from geometric confinement on the emergence and spatial patterning of CSCs in GBM *** study identified distinct spatial distributions of GBM CSCs in different geometric patterns,where CSCs mostly emerged in the peripheral *** spatial pattern of CSCs was found to correspond to the gradients of mechanical stresses resulted from the interplay between the cell-ECM and cell–cell interactions within the confined *** mechanistic study highlighted a Piezo1-RhoA-focal adhesion signaling axis in regulating GBM cell mechanosensing and the subsequent CSC phenotypic *** findings provide new insights into the biophysical origin of the unique spatial pattern of CSCs in GBM tumor and offer potential avenues for targeted therapeutic interventions.

关键词： Glioblastoma Cancer stem cell Mechanotransduction Traction force Piezo1

Improving the performance of LOX/kerosene upper stage rocket engines

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Propulsion and Power Research 2017年第3期6卷 157-176页

作者： Igor N.Nikischenko raymond D.Wright Roman A.Marchan Firefly Europe B.V. Blaricum 1261 GAThe Netherlands Spacefleet Ltd DevizesWiltshireSN103APUnited Kingdom

Improved liquid rocket engine cycles were proposed and analyzed via comparison with existing staged combustion and gas-generator *** key features of the proposed cycles are regenerative cooling of thrust chamber by oxygen and subsequent use of this oxygen for driving one or two oxygen *** fuel pump(s)are driven in a conventional manner,for example,using a fuel-rich gas-generator *** with staged combustion cycle based on oxygen-rich pre-burner showed that one of the proposed semi-expander cycles has a specific impulse only on 0.4%lower while providing much lower oxygen temperature,more efficient tank pressurizing system and built-in roll *** semi-expander cycle can be considered as a more reliable and cost-effective alternative of staged combustion *** semi-expander cycle can be considered as an improvement of gas-generator *** proposed semi-expander cycles were developed as a derivative of thrust chamber regenerative cooling performed by *** of existing oxygen/kerosene engines showed that replacing of kerosene regenerative cooling with oxygen allows a significant increase of achievable specific impulse,via optimization of mixture *** is especially the case for upper stage *** increasing of propellants average density can be considered as an additional benefit of mixture ratio *** was demonstrated that oxygen regenerative cooling of thrust chamber is a feasible and the most promising option for oxygen/kerosene *** of oxygen regenerative cooling and semi-expander cycles potentially allows creating the oxygen/kerosene propulsion systems with minimum specific impulse *** is important that such propulsion systems can be fully based on inherited and well-proven technical solutions.A hypothetic upper stage engine with thrust 19.6 kN was chosen as a prospective candidate for theoretical analysis of the proposed semi-expander *** newly-developed software RECS

关键词： Oxygen Kerosene Liquid rocket engine Upper stage

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驱动基因作为肺癌预防和治疗的靶标(英文)

化学进展 2013年第9期25卷 1517-1525页

作者：熊东海 raymond U.Osarogiagbon 王嫣尤明 Medical College of Wisconsin Cancer Center Medical College of Wisconsin Multidisciplinary Thoracic Oncology Program Baptist Cancer Center 80 Humphries Center Drive Department of Surgery and The Alvin j.Siteman Cancer Center Washington University School of Medicine

下一代测序(next generation sequencing,NGS)已经被广泛用于鉴定导致肺癌最重要的驱动基因。与Sanger测序等传统测序策略相比,NGS具有若干突出优势,包括能测定全基因组、全外显子组或转录组中几乎所有基因的序列,能同时检测如碱基替换... 详细信息

下一代测序(next generation sequencing,NGS)已经被广泛用于鉴定导致肺癌最重要的驱动基因。与Sanger测序等传统测序策略相比,NGS具有若干突出优势,包括能测定全基因组、全外显子组或转录组中几乎所有基因的序列,能同时检测如碱基替换(突变)、插入、缺失、拷贝数变种、结构变种、基因融合等等。近几年来,科学家们成功地对肺腺癌、鳞癌和小细胞癌等三种肺癌进行了若干综合性的NGS研究,一方面验证了此前已发现的肺癌驱动基因的重要性,另一方面揭示了一些此前在肺癌中未被深入研究的重要驱动基因。在所研究的大多数肺癌样本中存在这些基因的功能性体细胞基因变异,导致了对肺癌发展具有直接影响的关键信号通路的异常。可以预期,不断被发现了解的新肺癌驱动基因将为发现肺癌预防和治疗最佳靶标提供前所未有的机遇。

关键词：下一代测序(NGS) 驱动基因肺癌预防

TMAS:A transaction misbehavior analysis scheme for blockchain

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Blockchain(Research and Applications) 2024年第3期5卷 42-52页

作者： Shiyong Huang Xiaohan Hao Yani Sun Chenhuang Wu Huimin Li Wei Ren Kim-Kwang raymond Choo School of Computer Science China University of GeosciencesWuhan430074China Artificial Intelligence Thrust Information HubHong Kong University of Science and TechnologyGuangzhou511400China Yunnan Key Laboratory of Blockchain Application Technology Yunnan Innovation Institute of Beihang UniversityKunming650233China Fuj.an Key Laboratory of Financial Information Processing Putian UniversityPutian351100China Department of Information Systems and Cyber Security University of Texas at San AntonioSan AntonioTX 78249-0631USA

Blockchain-based cryptocurrencies,such as Bitcoins,are increasingly ***,the decentralized and anonymous nature of these currencies can also be(ab)used for nefarious activities such as money laundering,thus reinforcing the importance of designing tools to effectively detect malicious transaction *** this paper,we propose TMAS,a transaction misbehavior analysis scheme for blockchain-based ***,the proposed system includes ten features in the transaction graph,two heuristic money laundering models,and an analysis method for account linkage,which identifies accounts that are distinct but controlled by an identical *** evaluate the effectiveness of our proposed indicators and models,we analyze 100 million transactions and compute transaction features,and are able to identify a number of suspicious ***,the proposed methods can be applied to other cryptocurrencies,such as token-based cryptocurrencies(e.g.,Bitcoins)and account-based cryptocurrencies(e.g.,Ethereum).

关键词： Blockchain Anti-money laundering Bitcoin Cyptocurrency

Advances in Underground Construction Help Provide Quality of Life for Modern Societies

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Engineering 2017年第6期3卷 780-781页

作者： raymond L. Sterling Professor Emeritus Louisiana Tech University USA

In a technological world that is increasingly being changed by advances at the tiniest of scales-in chemical engineering, bioengineer- ing, computing, mechanical engineering, and other fields-it is worth examining the changes that are being made by large-scale engineering endeavors that impact the quality of life of billions of people around the world.

关键词：地下空间

Geodynamic evolution of the Tethyan lithosphere as recorded in the Spontang Ophiolite,South Ladakh ophiolites(NW Himalaya,India)

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Geoscience Frontiers 2022年第1期13卷 326-349页

作者： Mallika K.j.nnalagadda Mathieu Benoit Shivani Harshe Romain Tilhac raymond A.Duraiswami Michel Grégoire Nitin R.Karmalkar Interdisciplinary School of Science Savitribai Phule Pune UniversityPune 411007India Department of Geology Savitribai Phule Pune UniversityPune 411007India Géosciences Environnement Toulouse CNRS-CNES-IRD-UniversitéPaul SabatierObservatoire Midi Pyrénées31400 ToulouseFrance Instituto Andaluz de Ciencias de la Tierra(IACT) CSIC–Universidad de Granada18100 ArmillaGranadaSpain Vice-Chancellor’s Office Savitribai Phule Pune UniversityPune 411007India

The Spontang Ophiolite complex represents the most complete ophiolite sequence amongst the South Ladakh ophiolites and comprises mantle rocks(depleted harzburgites,dunites and minor lherzolites)as well as crustal rocks(basalt,isotropic gabbros,layered gabbros etc.).In the present study,detailed geochemistry(whole rock as well as mineral chemistry)and Sr-Nd isotopic analyses of thirty-six ultramaficmafic samples have been attempted to constraint the evolution and petrogenetic history of the Tethyan oceanic ***,trace-element and REE patterns of the peridotites and their minerals indicate that the lherzolites experienced lower degrees of partial melting resembling abyssal peridotites(at higher temperatures,TREE=$1216℃)than the harzburgites(6%–8%versus 15%–17%).Elevated eNd(t)and variable^(87) Sr/^(86) Sr(t)ratios along with REE patterns suggest that the Spontang mafic rocks display N-MORB affinity with negligible participation of oceanic sediments in their genesis are originated from a depleted upper mantle with little contribution from subduction-related ***-type Neotethyan oceanic crust is associated with the earliest phase of subduction(of older j.rassic age)through which a younger intra-oceanic island arc(Spong arc)subsequently *** REE display typical U-shaped patterns,suggesting that these rocks have been metasomatized by LREE-enriched *** the other side,mafic rocks are characterized by heterogeneous(Nb/La)PMand(Hf/Sm)PMand relatively homogeneous eNd(t),indicating interaction of subduction-related melts with the upper mantle during the initiation of subduction,in Early Cretaceous times.

关键词： Peridotites Mafic rocks Partial melting Metasomatism Ladakh

Effect of the sintering technique on the ferroelectric and d33 piezoelectric coefficients of Bi0.5(Na0.84K0.16)0.5TiO3 ceramic

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j.urnal of Advanced Ceramics 2019年第2期8卷 278-288页

作者： G.HERNANDEZ-CUEVAS j.R.LEYVA MENDOZA P.E.GARCíA-CASILLAS C.A.RODRíGUEZ GONZáLEZ j.F.HERNANDEZ-PAZ G.HERRERA-PéREZ L.FUENTES-COBAS S.DíAZ DE LA TORRE O.raymond-HERRERA H.CAMACHO-MONTES Instituto de Ingeniería y Tecnología Universidad Autónoma de Ciudad JuárezAv.Del Charro 450 Norte Cd.JuárezChihuahua32310México Centro de Investigación en Materiales Avanzados Miguel de Cervantes 120Chihuahua 31109ChihuahuaMéxico Centro de Investigación e Innovación Tecnológica Instituto Politécnico NacionalCerrada de Cecati s/nAzcapotzalcoSanta Catarina02250Ciudad de MéxicoMéxico Centro de Nanociencias y Nanotecnología Universidad Nacional Autónoma de MéxicoKm.107 Carretera Tijuana-EnsenadaAP.14Ensenada 22860Baja CaliforniaMéxico

In the search of lead-free piezoelectric materials,ceramic processing techniques offer potential tools to increase the piezoelectric and ferroelectric properties in addition to new chemical *** of pure BNKT16(Bi0.5(Na0.84K0.16)0.5TiO3)phase were synthesized by sol–gel method with a low crystallization temperature(750℃).Ceramic samples were sintered by pressureless sintering(PLS),sinter-forging(SF),and spark plasma sintering(SPS)***,morphological,and chemical characterizations were performed by XRD,Raman,EDS,and *** samples by PLS and SF exhibit rod-like grains associated to bismuth *** highest remanent polarization(11.05μC/cm2),coercive field(26.2 kV/mm),and piezoelectric coefficient(165 pC/N)were obtained for SF *** piezoresponse force microscopy(PFM)analysis shows that the crystallites at the nanoscale exhibit piezoelectric phenomenon and the highest piezoelectric response is reported for PLS *** presence of the rhombohedral phase,the increase in grain and crystallite size,and the oriented rod-like inclusions favoring the crystallographic texture are facts that enhance the piezoelectric coefficient for BNKT16 piezoceramics.

关键词： lead-free piezoelectrics sol–gel pressureless sintering (PLS) sinter-forging (SF) spark plasma sintering(SPS) piezoresponse

Spatial heterogeneity and population risk analysis of cotton bollworm, Helicoverpa armigera, in ChinaKey words spatial characteristics, spatial pattern, semivariance, population management, geostatistics, Helicoverpa armigera, population regulation

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Insect Science 2005年第4期12卷 255-262页

作者： SHAO-KUI GE raymond I. CARRUTHERS ZU-FEI MA GUANG XUEZHANG DIAN-MO LI State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of SciencesBeijing China USDA-ARS Exotic & Invasive Weeds Research Unit Albany California US

In this study, semivariance was used to quantitatively measure the spatial heterogeneity for the egg population of cotton bollworm during a growing season. The typical characteristic parameters of theoretical semivariance models against lag distances were applied to measure components of spatial heterogeneity： trend, range, spatial dependence, and the strength of spatial dependence. Then, kriging interpolation was used to evaluate the population risk of cotton bollworm exceeding economic thresholds. From early j.ne through early September, the population densities were sampled 10 times in the study field. Results showed that the spatial patterns were related to population density. For its low-density population, the spatially heterogeneous trends were usually of spherical shapes; but for highdensity ones, the trends shifted to Gaussian shapes. The spatial dependence appeared at varied distances ranging from 52 meters to 936 meters, and the spatial dependence was in the range of 0.39-288.60, which changed with population densities. While having high heterogeneity, the strength of spatial dependence became much stronger. Results of population risk analysis showed that there was a high risk during its early stages, especially in mid-j.ne. In August, population risk was so low that it did not need to be controlled.

关键词： spatial characteristics spatial pattern semivariance population management geostausucs Helicoverpa armigera population regulation

Expression of O<sup>6</sup>-Methylguanine-DNA Methyltransferase Examined by Alkyl-Transfer Assays, Methylation-Specific PCR and Western Blots in Tumors and Matched Normal Tissue

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j.urnal of Cancer Therapy 2013年第4期4卷 919-931页

作者： Kimiko Ishiguro Krishnamurthy Shyam Philip G. Penketh raymond P. Baumann Alan C. Sartorelli Thomas j. Rutherford Elena S. Ratner Department of Pharmacology and Developmental Therapeutics Program Cancer Center Yale University School of Medicine New Haven USA Division of Gynecologic Oncology Department of Obstetrics and Gynecology Yale University School of Medicine New Haven USA

The tumor selectivity of alkylating agents that produce guanine O6-chloroethyl (laromustine and carmustine) and O6-methyl (temozolomide) lesions depends upon O6-methylguanine-DNA methyltransferase (MGMT) activity being lower in tumor than in host tissue. Despite the established role of MGMT as a tumor resistance factor, consensus on how to assess MGMT expression in clinical samples is unsettled. The aim of this study is to examine the relationship between the values derived from distinctive MGMT measurements in 13, 12, 6 and 2 pairs of human tumors and matched normal adj.cent tissue from the colon, kidney, lung and liver, respectively, and in human cell lines. The MGMT measurements included 1) alkyl-transfer assays using [benzene-3H]O6-benzylguanine as a substrate to assess functional MGMT activity, 2) methylation-specific PCR (MSP) to probe MGMT gene promoter CpG methylations as a measure of gene silencing, and 3) western immunoblots to analyze the MGMT protein. In human cell lines, a strict negative correlation existed between MGMT activity and the extent of promoter methylation. In tissue specimens, by contrast, the correlation between these two variables was low. Moreover, alkyl-transfer assays identified 3 pairs of tumors and normal tissue with tumor-selective reduction in MGMT activity in the absence of promoter methylation. Cell line MGMT migrated as a single band in western analyses, whereas tissue MGMT was heterogeneous around its molecular size and at much higher molecular masses, indicative of multi-layered post-translational modifications. Malignancy is occasionally associated with a mobility shift in MGMT. Contrary to the prevalent expectation that MGMT expression is governed at the level of gene silencing, these data suggest that other mechanisms that can lead to tumorselective reduction in MGMT activity exist in human tissue.

关键词： O6-Methylguanine-DNA Methyltransferase (MGMT O6-Alkylguanine-DNA Alkyltransferase AGT) [Benzene-3H]O6-Benzylguanine Methylation-Specific PCR (MSP) Laromustine (Onrigin Cloretazine VNP40101M 101M) Temozolomide