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Micro-ESR:微型电子自旋共振光谱仪

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生命科学仪器 2011年第3期9卷 23-26页

作者： christopher J.WHItE Colin t.elliott James R.WHItE Active Spectrum Inc.

电子自旋共振光谱(ESR),又称顺磁共振光谱(EPR),是直接检测自由基、引起石油氧化降解含有未成对电子的活性分子以及食物的唯一方法,也在生物化学研究疾病方面起着一定的作用。本文所描述的微型、高灵敏度的ESR光谱仪通过显著降低光谱技... 详细信息

电子自旋共振光谱(ESR),又称顺磁共振光谱(EPR),是直接检测自由基、引起石油氧化降解含有未成对电子的活性分子以及食物的唯一方法,也在生物化学研究疾病方面起着一定的作用。本文所描述的微型、高灵敏度的ESR光谱仪通过显著降低光谱技术的成本,能够为工业和科学研究者扩大ESR光谱学的实用范围。

关键词：电子自旋共振光谱光谱仪微型科学研究者顺磁共振直接检测活性分子氧化降解

Role of the histone methyltransferases Ezh2 and Suv4-20h1/Suv4-20h2 in neurogenesis

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Neural Regeneration Research 2023年第3期18卷 469-473页

作者： christopher t.Rhodes Chin-Hsing Annie Lin Eunice Kennedy Shriver National Institute of Child Health and Human Development(NICHD) National Institutes of Health(NIH)BethesdaMDUSA Department of Integrative Biology University of Texas at San AntonioSan AntonioTXUSA University of texas at San Antonio Neurosciences Institute San AntonioTXUSA

Mechanisms regulating neurogenesis involve broad and complex processes that represent intriguing therapeutic targets in the field of regenerative *** influential factor guiding neural stem cell proliferation and cellular differentiation during neurogenesis are epigenetic *** present an overview of epigenetic mechanisms including chromatin structure and histone modifications;and discuss novel roles of two histone modifiers,Ezh2 and Suv4-20h1/Suv4-20h2(collectively referred to as Suv4-20h),in neurodevelopment and *** review will focus on broadly reviewing epigenetic regulatory components,the roles of epigenetic components during neurogenesis,and potential applications in regenerative medicine.

关键词： adult neurogenesis epigenetic Ezh2 histone co-regulation histone modification neurodevelopment neurogenesis regenerative medicine Suv4-20h

Molecular anatomy and pathogenic actions of Helicobacter pylori CagA that underpin gastric carcinogenesis

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Cellular & Molecular Immunology 2020年第1期17卷 50-63页

作者： Atsushi takahashi-Kanemitsu christopher t.Knight Masanori Hatakeyama Department of Microbiology Graduate School of MedicineThe University of TokyoTokyoJapan

Chronic infection with Helicobacter pylori cagA-positive strains is the strongest risk factor for gastric *** cagA gene product,CagA,is delivered into gastric epithelial cells via the bacterial type IV secretion *** CagA then undergoes tyrosine phosphorylation at the Glu-Pro-Ile-tyr-Ala(EPIYA)motifs in its C-terminal region and acts as an oncogenic scaffold protein that physically interacts with multiple host signaling proteins in both tyrosine phosphorylation-dependent and-independent *** of CagA using in vitro cultured gastric epithelial cells has indicated that the nonphysiological scaffolding actions of CagA cell-autonomously promote the malignant transformation of the cells by endowing the cells with multiple phenotypic cancer hallmarks:sustained proliferation,evasion of growth suppressors,invasiveness,resistance to cell death,and genomic *** expression of CagA in mice leads to in vivo oncogenic action of CagA without any overt *** in vivo oncogenic activity of CagA is further potentiated in the presence of chronic *** Helicobacter pylori infection triggers a proinflammatory response in host cells,a feedforward stimulation loop that augments the oncogenic actions of CagA and inflammation is created in CagA-injected gastric *** that Helicobacter pylori is no longer colonized in established gastric cancer lesions,the multistep nature of gastric cancer development should include a“hit-and-run”process of CagA ***,acquisition of genetic and epigenetic alterations that compensate for CagA-directed cancer hallmarks may be required for completion of the“hit-and-run”process of gastric carcinogenesis.

关键词： cagA/CagA Helicobacter pylori SHP2 PAR1 inflammation “hit-and-run”carcinogenesis

Introduction to social sensing and big data computing for disaster management

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International Journal of Digital Earth 2019年第11期12卷 1198-1204页

作者： Zhenlong Li Qunying Huang christopher t.Emrich Geoinformation and Big Data Research Laboratory Department of GeographyUniversity of South CarolinaColumbiaSCUSA Department of Geography University of Wisconsin-MadisonMadisonWIUSA School of Public Administration and National Center for Integrated Coastal Research University of Central FloridaOrlandoFLUSA

traditional data collection methods such as remote sensing and field surveying often fail to offer timely information during or immediately following disaster *** sensing enables all citizens to become part of a large sensor network,which is low cost,more comprehensive,and always broadcasting situational awareness ***,data collected with social sensing is often massive,heterogeneous,noisy,unreliable from some aspects,comes in continuous streams,and often lacks geospatial reference ***,these issues represent a grand challenge toward fully leveraging social sensing for emergency management decision making under extreme ***,big data computing methods and technologies such as high-performance computing,deep learning,and multi-source data fusion become critical components of using social sensing to understand the impact of and response to the disaster events in a timely *** special issue captures recent advancements in leveraging social sensing and big data computing for supporting disaster *** analyzed within these papers are some of the promises and pitfalls of social sensing data for disaster relevant information extraction,impact area assessment,population mapping,occurrence patterns,geographical disparities in social media use,and inclusion in larger decision support systems.

关键词： Social media VGI big data natural hazards spatial computing

Modelling of the behavior of marine oil spills: applications based on random walk techniques

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Journal of Environmental Sciences 2000年第1期12卷 3-8页

作者： Li, Zhi-Wei Mead, christopher t. Zhang, Shu-Shen Dept. of Environ. Sci. and technol. Dalian University of Technology Dalian 116012 China HR Wallingford Howbery Park Wallingford Oxon OX10 8BA United Kingdom

A numerical model has been developed to simulate the transport and fate of oil spilled at sea. the model combines the transport and fate processes of spilled oil with the random walk technique. Oil movement under the influence of tidal currents, wind driven currents, and turbulent eddies is simulated by the PLUME RW dispersion model developed by HR Wallingford. the weathering processes in the model represent physical and chemical changes of soil slicks with time, and comprise mechanical spreading, dispersion, evaporation and emulsification. Shoreline stranding is determined approximately using a capacity method for different shoreline types. this paper presents details of the model, and describe the results of various sensitivity tests. the model is suitable for oil spill contingency planning.

关键词： oil spill modelling random walk technique CLC number: tQ021 4 Document code: A

A population study of fasting time and serum prostate-specific antigen （PSA） level

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Asian Journal of Andrology 2014年第5期16卷 740-744,I0009,I0010页

作者： Cheryl K Lau Maggie Guo Jeannine A Viczko christopher t Naugler Calgary Laboratory Services Calgary Department of Family Medicine University of Calgary Calgary Canada Department of Pathology and Laboratory Medicine Department of Family Medicine University of Calgary Calgary Canada

Prostate cancer is one of the most common cancers in men. traditional screening and diagnostic methods include digital rectal examinations （DREs）, biopsies and serum prostate-specific antigen （PSA） tests, with the latter being the more popular. PSA is a biomarker for prostate cancer; however, it is highly sensitive to external factors as well as other prostate diseases. As such, the reliability of of the serum PSA level as a sole screening and diagnostic tool for prostate cancer is controversial. Recently, it has been shown that fasting extremes can affect concentrations of serum chemistry analytes, thus raising the question of whether or not fasting has an effect on the highly sensitive PSA biomarker. Patients testing for serum PSA levels are often concomitantly submitting to other tests that require fasting, subjecting certain patients to a fasting PSA level while others not. the objective of this study was to investigate whether this discrepancy in fasting state translates into an effect on serum PSA levels. Serum PSA levels and fasting time records for 157 276 men who underwent testing at Calgary Laboratory Services （CLS; Calgary, Alberta, Canada） between 01 January 2010 and 31 March 2013 were accessed. Linear regression models of mean PSA levels and fasting times revealed a statistically important relationship at certain fasting times. Applying a dynamic mathematical model to explore the clinical effect of fasting suggests minimal impact on serum PSA result interpretation. thus, patients can be tested for serum PSA levels regardless of their fasting state.

关键词： diagnostic test fasting prostate-specific antigen (PSA)

Protecting miners from coal bursts during development above historic mine workings in Harlan County,KY

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International Journal of Mining Science and technology 2021年第1期31卷 111-116页

作者： christopher Mark Mine Safety and Health Administration PittsburghPA 15236USA

In order to reach a large,untapped reserve of high-quality coal,D8 Cloverlick Mine proposed to mine a corridor nearly 600 m deep beneath the Benham Spur of Black Mountain,Kentucky’s highest peak.D8 Cloverlick Mine was extracting the Owl seam,but the corridor’s route lay approximately 20 m above century-old mine workings in the C–(Darby)*** to the concern,three serious coal bursts had recently occurred in nearby Owl seam *** of the old workings seemed to indicate that the underlying C–seam had been fully ***,two of the coal bursts had occurred above areas where the C–Seam was also shown as mined *** Safety and Health Administration(MSHA)technical Support therefore investigated the records of past mining to better understand the old mine *** conditions observed in current Owl seam workings were also compared with the maps of the old C–seam *** study concluded that the presence of hazardous underlying remnants could not be ruled *** mitigate the burst risk,D8 Cloverlick Mine adopted a strategy of stress probe drilling.A self-propelled coal drill was used to auger 11.5-m-long,small diameter holes in advance of *** each hole was drilled,the cuttings were measured to detect the presence of highly stressed *** the crossing was successfully completed without incident.

关键词： Coal bursts Underground mining Room-and-pillar Destressing

Application of multiphoton microscopy in dermatological studies: A mini-review

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Journal of Innovative Optical Health Sciences 2014年第5期7卷 39-63页

作者： Eljah Yew christopher R.owlands Peter t.C.So Singapore-MIt Alliance for Researchand technology(SMARt) 1 CREATE WayCREATE TowerSingapore 138602 Department of Biological Engineering Massachusetts Institute of technology 77 Massachusetts Ave Cambridge MA 02139USA Department of Mechanical Engineering Massachusetts In.stitute of technology 77 Massachusetts Ave Cambridge MA 02139USA SGR Harrison Spectroscopy Laboratory 77 Massachusetts Ave Cambridge MA 02139USA

this review summarizes the historical and more recent developments of multiphoton microscopy,as applied to *** microscopy offers several advantages over competingmicroscopy techniques:there is an inherent axial sectioning,penetration depths that competewll with confocal microscopy on account of the use of near-infrared light,and many t wo-pho ton contrast mechanisms,such as second-harmonic generation,have no analogue in *** the penetration depths of photons into tissue are typically limited on the orderof hundreds of microns,this is of les concern in dermatology,as the skin is thin and *** a result,multiphoton microscopy in dermatology has generated a great deal ofmterest,much of which is summarized *** review covers the interaction of light and tissue,as well as the various considerations that must be made when designing an *** stateof multiphoton microscopy in imaging skin cancer and various other diseases is also discussed,along with the investigation of aging and regeneration phenomena,and finally,the use of mul-tiphoton microscopy to analyze the transdermal transport of drugs,cosmetics and other agents *** review concludes with a look at potential future research directions,especiallythose that are necessary to push these techniques into widespread clinical acceptance.

关键词： Multiphoton microscopy skin cancer,aging and regeneration.

Design to reduce electromagnetic vibration in integral-slot SPM machine considering force modulation effect

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Science China(technological Sciences) 2022年第8期65卷 1867-1877页

作者： ZHU ShengDao ZHAO WenXiang JI JingHua LIU GuoHai LEE christopher H.t. School of Electrical and Information Engineering Jiangsu UniversityZhenjiang 212013China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

In this paper, two different designs, with dummy slots and bread-loaf magnets techniques, are presented to reduce the electromagnetic vibration in integral-slot surface-mounted permanent-magnet(SPM) machines. Firstly, the stator slotting effect on the magnetic field modulation and radial force modulation is investigated. It reveals the amplitude of the modulated magnetic field and modulated radial force is greatly affected by the slot opening effect, while the spatial order is closely associated with the slot numbers. Subsequently, the dummy slots and bread-loaf magnets design are developed for a 36-slot/12-pole integral-slot SPM machine to reduce the electromagnetic vibration. Finally, two SPM machines, with conventional and bread-loaf magnets,are manufactured. Experimental tests are carried out to validate the theoretical analyses.

关键词： surface-mounted permanent-magnet machine slot opening width dummy slots bread-loaf magnets vibration reduction

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