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HPLC separation of higher fullerenes in the synthetical "graphite smokes" soot

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Chinese Journal Of Geochemistry 2012年第3期31卷 303-308页

作者： ZHANG Jun Luann becker LIANGHandong LUO Yang XU Wei WANG Hongcui Water Environmental Monitoring Center Haihe River Water Conservancy CommissionMinistry of Water ResourcesTianjin 300170China Department of Physics and Astronomy Johns Hopkins UniversityBaltimoreMD 21218USA State Key Laboratory of Coal Resources and Safety Mining China University of Mining and TechnologyBeijing 100083China

Higher fullerenes(C84,C90,C92,C94 and C96) were successfully isolated from the Soxhlet extract of the synthetical "Graphote Smokes" soot(GS sample) by using a big Cosmosil Buckysep(Phenomenex) column(250 mm × 10 mm) with a large *** fractions isolated have been determined by high performance liquid chro-matography(HPLC) and laser desorption mass spectrometry(LDMS).It is found that there are different fullerenes molecules in different fractions with retention *** result indicates that fullerenes do exist in GS ***,it excludes the suspicion to some extent that fullerene molecules might be generated by the laser desorption process in the *** addition,it also provides the experimental basis for the study of natural higher fullerenes and might be helpful to figure out the question if higher fullerenes do exist in the natural samples.

关键词：富勒烯分子 HPLC 分离高效液相色谱仪煤烟吸烟石墨大容量注射剂

Extracellular matrices, artificial neural scaffolds and the promise of neural regeneration

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Neural Regeneration Research 2014年第17期9卷 1573-1577页

作者： Christian B.Ricks Samuel S.Shin Christopher becker Ramesh Grandhi Department of Neurological Surgery University of Pittsburgh Medical CenterPittsburghPAUSA University of Pittsburgh School of Medicine PittsburghPAUSA

Over last 20 years, extracellular matrices have been shown to be useful in promoting tissue regeneration. Recently, they have been used and have had success in achieving neurogenesis. Recent developments in extracellular matrix design have allowed their successful in vivo incorporation to engender an environment favorable for neural regeneration in animal models. Promising treatments under investigation include manipulation of the intrinsic extracellular matrix and incorporation of engineered naometer-sized scaffolds through which inhibition of molecules serving as barriers to neuroregeneration and delivery of neurotrophic factors and/or cells for successful tissue regeneration can be achieved. Further understanding of the changes incurred within the extracellular matrix following central nervous system injury will undoubtedly help design a clinically efficacious extracellular matrix scaffold that can mitigate or reverse neural degeneration in the clinical setting.

关键词： extraceUular matrix neurogenesis scaffolds neural stem cells

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西欧晚泥盆世法门期早期石燕贝类腕足动物

古生物学报 2023年第3期62卷 350-375页

作者：王艺凝马学平 Volker Ebbighausen R.Thomas becker 北京大学地球与空间科学学院造山带与地壳演化教育部重点实验室北京100871 Geologisch-Palaontologisches Institut und Museum Westfalische Wilhelms-Universitat MunsterD-48149 MunsterGermany

比利时新基尔里斯(Senzeilles)地区是西欧晚泥盆世地层研究的一个经典地区,也是法门期石燕贝类腕足动物的重要比产区。然而针对本区弓石燕类的现代研究却较为匮乏,此外,早期的分类工作已难以满足现代专题性的课题资料要求(即层位清楚、... 详细信息

比利时新基尔里斯(Senzeilles)地区是西欧晚泥盆世地层研究的一个经典地区,也是法门期石燕贝类腕足动物的重要比产区。然而针对本区弓石燕类的现代研究却较为匮乏,此外,早期的分类工作已难以满足现代专题性的课题资料要求(即层位清楚、鉴定准确的系统分类工作),因此对比利时地区法门期的“弓石燕属”足动物进行系统古生物学研究及对比具有重要意义。当前研究在华南现有成果的基础上,通过对壳面特征(贝体大小、基面特征、微细纹饰特征、中槽壳褶发生方式)及内部构造(齿板特征、内窗板特征等)的系统研究及对比,拓展了Plicapustula属的定义,即:褶上和褶间均发育微瘤纹饰。欧洲的Plicapustula属分子褶间均发育放射状细瘤微细纹饰,而华南的该属分子褶间均缺失微瘤纹饰。由于该特征存在明显的地域性,因此当前研究以此为依据建立了Paraplicapustula亚属,并将欧洲的标本归入该亚属。此外,本文还首次识别并描述了欧洲的Sinospirifer属。大部分西欧Sinospirifer属和Plicapustula属与华南地区相比,在种级组成上存在明显的差异,包括标本大小、齿板是否增厚、壳褶数目及分枝情况、微细纹饰类型等。本文共描述了上述2属的5种,包括1新亚属、3新种[Plicapustula(Paraplicapustula) eleganta subgen. et sp. nov. Ma and Wang, Plicapustula(Paraplicapustula) magna subgen. et ***. Ma and Wang, Sinospirifer transversus sp. nov. Ma and Wang, Plicapustula(Paraplicapustula) sp.及Sinospirifer subextensus(Martelli, 1902)]。

关键词：中国石燕褶瘤石燕副褶瘤石燕华南西欧晚泥盆世腕足动物

Special Topic:Propulsion Systems with Low Emission and Low Noise

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Chinese Journal of Aeronautics 2023年第5期36卷 I0001-I0001页

作者： Dan ZHAO Sid becker Master Engineering Studies in the Faculty of Engineering at the University of Canterbury the Faculty of Engineering at the University of Canterbury

With the emergence of global warming and various extreme climates,governance has become one of the focus of attention in the current development process of the international *** reducing the emission of carbon dioxide,nitrogen oxides and particles,we can save energy,reduce the damage to the environment,and simultaneously create a more comfortable human living *** the past decades,much more advanced thermodynamics,heat transfer and clean combustion technologies have been developed,such as chemical looping combustion,alkaline combustion technology,porous medium combustion and collaborative control based on fuel characteristics(Oxy-fuel,Ammonia/Hydrogen)and combustion conditions(high pressure or high Mach number).

关键词： thermodynamics dioxide extreme

Pancreatic ductal adenocarcinoma: Risk factors, screening, and early detection

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World Journal of Gastroenterology 2014年第32期20卷 11182-11198页

作者： Andrew E becker Yasmin G Hernandez Harold Frucht Aimee L Lucas Henry D. Janowitz Division of Gastroenterology Icahn School of Medicine at Mount Sinai New York NY 10029 United States Division of Digestive and Liver Diseases Columbia University College New York NY 10032 United States

Pancreatic cancer is the fourth most common cause of cancer-related deaths in the United States, with over 38000 deaths in 2013. The opportunity to detect pancreatic cancer while it is still curable is dependent on our ability to identify and screen high-risk populations before their symptoms arise. Risk factors for developing pancreatic cancer include multiple genetic syndromes as well as modifiable risk factors. Genetic conditions include hereditary breast and ovarian cancer syndrome, Lynch Syndrome, familial adenomatous polyposis, Peutz-Jeghers Syndrome, familial atypical multiple mole melanoma syndrome, hereditary pancreatitis, cystic fibrosis, and ataxia-telangiectasia; having a genetic predisposition can raise the risk of developing pancreatic cancer up to 132-fold over the general population. Modifiable risk factors, which include tobacco exposure, alcohol use, chronic pancreatitis, diet, obesity, diabetes mellitus, as well as certain abdominal surgeries and infections, have also been shown to increase the risk of pancreatic cancer development. Several largevolume centers have initiated such screening protocols, and consensus-based guidelines for screening high-riskgroups have recently been published. The focus of this review will be both the genetic and modifiable risk factors implicated in pancreatic cancer, as well as a review of screening strategies and their diagnostic yields.

关键词： Pancreatic neoplasms Pancreas cancer screening Genetic predisposition to disease Hereditary breast and ovarian cancer syndrome Lynch syndrome Peutz-Jeghers BRCA PALB2 p16 Pancreatitis

H_(∞)control in the frequency domain for a semi-active floor isolation system

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Frontiers of Structural and Civil Engineering 2013年第3期7卷 264-275页

作者： Yundong SHI Tracy C becker Masahiro KURATA Masayoshi NAKASHIMA Graduate School of Engineering Kyoto UniversityKyoto 611-0011Japan Disaster Prevention Research Institute Kyoto UniversityKyoto 611-0011Japan

A floor isolation system installed in a single floor or room in a fixed base structure is designed to protect *** this configuration,the input motions to the floor isolation from the ground motions are filtered by the structure,leaving the majority of the frequency content of the input motion lower than the predominant frequency of the *** floor isolation system should minimize the acceleration to protect equipment;however,displacement must also be limited to save floor space,especially with long period ***-active control with an H_(∞)control was adopted for the floor isolation system and a new input shaping filter was developed to account for the input motion characteristics and enhance the effectiveness of the H_(∞)control.A series of shake table tests for a semi-active floor isolation system using rolling pendulum isolators and a magnetic-rheological damper were performed to validate the H_(∞)*** control using an oil damper was also tested for *** test results show that the H_(∞)control effectively reduced acceleration for short period motions with frequencies close to the predominant frequency of the structure,as well as effectively reduced displacement for long period motions with frequencies close to the natural frequency of the floor isolation *** H_(∞)control algorithm proved to be more advantageous than passive control because of its capacity to adjust control strategies according to the different motion frequency characteristics.

关键词： semi-active floor isolation H1 control MR damper shaping filter shaking table test

Predictive value of Ki67 and p53 in locally advanced rectal cancer:Correlation with thymidylate synthase and histopathological tumor regression after neoadjuvant 5-FU-based chemoradiotherapy

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World Journal of Gastroenterology 2008年第7期14卷 1060-1066页

作者： Christiane Jakob Torsten Liersch Wolfdietrich Meyer Heinz becker Gustavo B Baretton Daniela E Aust Institute for Pathology University of TechnologyFetscherstr. 74D-01307 DresdenGermany Department of General Visceral and Transplantation SurgeryUniversity Medical Center of GttingenRobert-Koch-Str. 40D-37075 GttingenGermany

AIM: To investigate the predictive value of Ki67 and p53 and their correlation with thymidylate synthase (TS) gene expression in a rectal cancer patient cohort treated according to a standardized recommended neoadjuvant treatment ***: Formalin fixed, paraffin embedded pre-therapeutical tumor biopsies (n = 22) and post-therapeutical resection specimens (n = 40) from patients with rectal adenocarcinoma (clinical UICC stage Ⅱ/Ⅲ) receiving standardized neoadjuvant 5-fluorouracil (5-FU) based chemoradiotherapy were studied for Ki67 and p53 expression by immunohistochemistry and correlated with TS mRNA expression by quantitative TaqMan real-time PCR after laser microdissection. The results were compared with histopathological tumor regression according to a standardized semiquantitative score grading ***: Responders (patients with high tumor regression) showed a significantly lower Ki67 expression than non-responders in the pre-therapeutical tumor biopsies (81.2% vs 16.7%; P < 0.05) as well as in the post-therapeutical resection specimens (75.8% vs 14.3%; P < 0.01). High TS mRNA expression was significantly correlated with a high Ki67 index and low TS mRNA expression was significantly correlated with a low Ki67 index in the pre-therapeutical tumor biopsies (corr. coef. = 0.46; P < 0.01) as well as in the post-therapeutical resection specimens (corr. coef. = 0.40; P < 0.05). No significant association was found between p53 and TS mRNA expression or tumor ***: Ki67 has, like TS, predictive value in rectal cancer patients after neoadjuvant 5-FU based chemoradiotherapy. The close correlation between Ki67 and TS indicates that TS is involved in active cell cycle processes.

关键词： p53 Ki67 Neoadjuvant treatment Rectal cancer Thymidylate synthase

Human papilloma virus and esophageal carcinoma in a Latin-American region

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World Journal of Gastroenterology 2009年第25期15卷 3142-3147页

作者： Roberto Herrera-Goepfert Marcela Lizano Suminori Akiba Adela Carrillo-García Mauricio becker-D'Acosta Department of Pathology National Cancer Institute Unit of Biomedical Research in Cancer National Cancer Institute and Biomedical Research InstituteNational Autonomous University of Mexico Department of Epidemiology and Preventive Medicine Kagoshima University Graduate School of Medical and Dental Sciences

AIM:To investigate the presence of high-risk human papilloma virus (HPV) in esophageal squamous cell carcinomas (ESCCs) in a non-selected Mexican ***: Cases with a pathological diagnosis of squamous cell carcinoma of the esophagus were obtained from Department of Pathology files, at the National Cancer Institute in Mexico City during the period between 2000 and 2008. Slides from each case were reviewed and cases with sufficient neoplastic tissue were selected for molecular analysis. DNA was extracted from paraffin-embedded tissue samples for polymerase chain reaction analysis to detect HPV DNA sequences. Demographic and clinical data of each patient were retrieved from corresponding clinical ***: HPV was detected in 15 (25%) of ESCCs. HPV-16 was the most frequently observed genotype, followed by HPV-18; HPV-59 was also detected in one case. Unfortunately, HPV genotype could not be established in three cases due to lack of material for direct sequencing, although universal primers detected the presence of HPV generic sequences. No low-risk HPV genotypes were found nor was HPV-16/18 co-infection. HPV presence in ESCC was not significantly associated with gender, age, alcohol consumption, smoking, anatomic location, or histologic grade. All patients belonged to low and very low socioeconomic strata, and were diagnosed at advanced disease stage. Male patients were most commonly affected and the male:female ratio in HPV-positive ESCC increased two- fold in comparison with HPV-negative cases (6.5:1 vs 3.1:1).CONCLUSION: High prevalence of high-risk HPV in ESCC in Mexico does not support the hypothesis that HPV-associated ESCC is more common in areas with higher ESCC incidence rates.

关键词： Esophagus Squamous cell carcinoma virusHuman papilloma virus High-risk human papilloma virus

Ephrin-B reverse signaling induces expression of wound healing associated genes in IEC-6 intestinal epithelial cells

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World Journal of Gastroenterology 2005年第29期11卷 4511-4518页

作者： Christian Hafner Stefanie Meyer Ilja Hagen Bernd becker Alexander Roesch Michael Landthaler Thomas Vogt Department of Dermatology University Hospital of Regensburg Regensburg D-93042 Germany

AIM： Eph receptors and ephrin ligands play a pivotal role in development and tissue maintenance. Since previous data have indicated an involvement of ephrin-B2 in epithelial healing, we investigated the gene expression and downstream signaling pathways induced by ephrin-B mediated cell-cell signaling in intestinal epithelial cells. METHODS： Upon stimulation of ephrin-B pathways in IEC-6 cells with recombinant rat EphB1-Fc, gene expression was analyzed by Affymetrix rat genome 230 high density arrays at different time points. Differentially expressed genes were confirmed by real-time RT-PCR. In addition, MAP kinase pathways and focal adhesion kinase （FAK） activation downstream of ephrin-B were investigated by immunoblotting and fluorescence microscopy. RESULTS： Stimulation of the ephrin-B reverse signaling pathway in IEC-6 cells induces predominant expression of genes known to be involved into wound healing/cell migration, antiapoptotic pathways, host defense and inflammation. Cox-2, c-Fos, Egr-1, Egr-2, and MCP-1 were found among the most significantly regulated genes. Furthermore, we show that the expression of repair- related genes is also accompanied by activation of the ERKI/2 MAP kinase pathway and FAK, two key regulators of epithelial restitution. CONCLUSION： Stimulation of the ephrin-B reverse signaling pathway induces a phenotype characterized by upregulation of repair-related genes, which may partially be mediated by ERK1/2 pathways.

关键词： Ephrin-B IEC-6 Wound healing Gene expression c-Fos Egr-1/2 COX-2