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Primary prevention of colorectal cancer:myth or reality?

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World Journal of Gastroenterology 2014年第41期20卷 15060-15069页

作者： marcela crosara Teixeira maria Ignez Braghiroli Jorge Sabbaga Paulo m hoff division of medical Oncology Instituto do Cancer do Estado de S?o PauloHospital Sírio Libanês

colorectal cancer incidence has been rising strongly in parallel with economic *** the past few decades,much has been learned about the lifestyle,dietary and medication risk factors for this *** respect to lifestyle,compelling evidence indicates that prevention of weight gain and maintenance of a reasonable level of physical activity can positively influence in lowering the *** there is controversy about the role of specific nutritional factors,consideration of dietary pattern as a whole appears useful for formulating *** quite often recommended,the role for many supplements,including omega-3,vitamin d,folate,and vitamin B6,remains *** calcium and vitamin d supplementation appear to add a modest benefit,particularly in those with a low daily *** regard to chemoprevention,medications such as aspirin and nonsteroidal antiinflammatory drugs,and postmenopausal hormonal replacement for women might be associated with substantial reductions in colorectal cancer risk,though their utility is affected by their side effect ***,the role of agents such as statins,bisphosphonates and antioxidants have yet to be ***,primary prevention strategies focusing on modifying environmental,lifestyle risk factors,and chemopreventive drugs are options that have already been tested,and may impact on colon cancer incidence.

关键词： Primary prevention colorectal cancer Physical activity diet chemoprevention

Photometric and Spectroscopic Study of Ten Low mass Ratio contact Binary Systems:Orbital Stability,O'connell Effect and Infrared calcium Line Filling

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Research in Astronomy and Astrophysics 2024年第8期24卷 212-222页

作者： Surjit S.Wadhwa Adam Popowicz Raúl michel Petar Kostić Oliver Vince Nick F.H.Tothill Ain Y.de Horta miroslav d.Filipović School of Science Western Sydney UniversityLocked Bag 1797PenrithNSW 2751Australia department of Electronics Electrical Engineering and MicroelectronicsSilesian University of TechnologyAkademicka 1644120 GliwicePoland Instituto de Astronomía UNAM.A.P.87722800 EnsenadaBCMéxico Astronomical Observatory Volgina 711060 BelgradeSerbia

Low mass ratio contact binary systems are more likely to have unstable orbits and potentially *** addition,such systems exhibit characteristics such as starspots and high energy emissions(UV)suggestive of chromospheric and magnetic *** curve modeling of ten contact binary systems is *** were found to be of extreme low mass ratio ranging from 0.122 to 0.24 and three were found to be potentially unstable and possible merger *** of the infrared calcium absorption lines is a marker of increased chromospheric *** use the available Large Sky Area multi-Object Fiber Spectroscopic Telescope spectra along with matched standard spectra(broadened for rotation)to measure the excess filling of the central core depression flux of the two main infrared calcium absorption linesλ8542 andλ*** find that all reported contact binaries have excess filling of the core flux in the infrared calcium *** of the systems reported were also observed by the Galaxy Evolution Explorer mission and we find that all three have features of excess ultraviolet emissions further adding evidence for increased chromospheric activity in low mass ratio contact *** of both orbital stability and absorption line filling is dependent on the determination of geometric and absolute parameters from light curve *** an insignificant number of contact binary light curves exhibit the O’connell effect,usually attributed to *** discuss the inclusion of starspots in light curve solutions and how they influence the geometric and absolute parameters.

关键词： (stars)binaries eclipsing-techniques photometric-stars chromospheres

RBc aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 53-65页

作者： m.K.maksimov P.B.Ermolinskiy O.N.Scheglovitova N.N.Sklyankina A.V.muravyov A.E.Lugovtsov A.V.Priezzhev Faculty of Physics M.V.Lomonosov Moscow State University bld.1subbuilding.2Leninskie goryMoscow 11991Russia N.F.Gamaleya National Research center for Epidemiology and microbiology 18 Gamaleya StreetMoscow 123098Russia K.d.Ushinsky Yaroslavl State Pedagogical University 108/1 Respublikanskaya StreetYaroslavl 150000Russia

Red blood cells(RBcs)are the most abundant human blood *** aggregation and deformation strongly determine blood viscosity which impacts hemorheology and *** turn,RBc properties depend on di®erent endogenous and exogenous *** such factor is nitric oxide(NO),which is mainly produced by endothelial cells(ec)from L-arginine amino acid in the circulatory *** the mechanisms of the RBc-endothelium interplay are not clear up to date and considering its possible clinical importance,the aims of this study are to investigate in vitro:(1)The e®ect of L-arginine induced NO on RBc aggregation and adhesion to endothelium;(2)the NO e®ect on RBc aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the *** RBc aggregation and adhesion to a monolayer of ec were studied using optical tweezers(OT).The RBc deformability and aggregation without endothelium in the samples were studied using the°ow chamber method and myrenne *** con¯rmed that NO increases deformability and decreases aggregation of *** showed that the soluble guanylate cyclase pathway appears to be the only NO signaling pathway *** the samples with the endothelium,the\bell-shaped"dependence of RBc aggregation force on L-arginine concentration was observed,which improves our knowledge about the process of NO production by ***,data related to L-arginine accumulation by endothelium were obtained:Necessity of the presence of extracellular L-arginine stated by other authors was put under *** our study,NO decreased the RBc-endothelium adhesion,however,the tendency appeared to be weak and was not con¯rmed in another set of *** our knowledge,this is the¯rst attempt to measure the forces of RBc adhesion to endothelium monolayer with OT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers myrenne flow chamber

Source apportionment of atmospheric particulate carbon in Las Vegas,Nevada,USA

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Particuology 2013年第1期11卷 110-118页

作者： mark c.Green Judith c.chow m.-c.Oliver chang L.-W.Antony chen Hampden d.Kuhns Vicken R.Etyemezian John G.Watson division of Atmospheric Sciences Desert Research Institute2215 Raggio ParkwayRenoNV 89512USA division of Atmospheric Sciences Desert Research Institute.2215 Raggio ParkwayRenoNV 89512USA State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'anChina california Air Resources Board 9528 Telstar Ave.El MonteCA 91731USA

A study was conducted to quantify wintertime contributions of source types to carbonaceous Pm2.5 at four urban sites in the Las Vegas Valley, one of the most rapidly growing urban areas in the southwestern United States. Twenty-four hour average ambient samples were collected for mass, ions, elements, organic carbon （Oc）, elemental carbon （ec）, and trace organic markers analysis. Additional measurements were made to determine diurnal patterns in light-absorbing black carbon （Bc） as a marker for combustion sources. carbonaceous Pm sources of on-road gasoline vehicles, on-road diesel vehicles, and off-road diesel engines were characterized with their chemical profiles, as well as fuel-based emission factors, using an In-Plume Sampling System. The Effective Variance chemical mass Balance （EV-cmB） source apportionment model was applied to the ambient samples collected, using source profiles developed in this study as well as profiles from other relevant studies. Four main sources contributed to Pm2.5 carbon within the Las Vegas Valley：（1） paved road dust, （2） on-road gasoline vehicles, （3） residential wood combustion, and （4） on-road diesel vehicles. cmB estimated that on-road mixed fleet gasoline vehicles are the largest source for Oc and ec at all the sites. The contribution of paved road dust to both Oc and ec was 5-10% at the four sites. On-road diesel vehicles contribute 22% of the Oc and 34% of the ec at a site near the city center, which is located immediately downwind of a major freeway. Residential wood combustion is a more important source than on-road diesel vehicles for two residential neighborhood sites, These results are consistent with our conceptual model, and the research methodology may be applied to studying other urban areas.

关键词： Source characterization mobile sources Elemental carbon Source apportionment Organic marker

Optical broadband monitoring of thin film growth

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光学精密工程 2005年第4期13卷 403-412页

作者： H. Ehlers T. Groβ m. Lappschies d. Ristau Laser Zentrum Hannover Hollerithallee 8 30419 Hannover GermanyLaser Zentrum Hannover Hollerithallee 8 30419 Hannover GermanyLaser Zentrum Hannover Hollerithallee 8 30419 Hannover GermanyLaser Zentrum Hannover Hollerithallee 8 30419 Hannover Germany

This contribution is focused on applications of spectroscopic methods for the precise control of deposition processes. In this context, the present study gives a review on selected combinations of conventional and ion deposition techniques with different broadband online spectrophotometric systems. Besides two systems operating in the VIS- and NIR-spectral range in combination with ion processes, also a monochromator system developed for conventional deposition processes in the dUV/VUV-spectral range will be discussed. The considerations will be concluded by a comparison of the major advantages of the specific combinations of processes with online monitoring concepts and by a brief outlook concerning future challenges.

关键词：宽带光学涂覆技术薄膜分光镜

Broadband Vibrational cooling of cold cesium molecules： Theory and Experiments

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chinese Journal of chemical Physics 2009年第2期22卷 149-156页

作者： d. Sofikitis A. Fioretti S. Weber m. Viteau A. chotia R. Horchani m. Allegrini B. chatel d. comparat P. Pillet Laboratoire Aimé cotton CNRS Université Paris-Sud Bat. 505 91405 Orsay France Laboratoire collisions Agrégats Réactivité (UMR 5589 CNRS-Université Paul Sabatier Toulouse 3) IRSAMC Toulouse France cNISm Dipartimento di Fisica Universita di Pisa Largo Pontecorvo 356127 PISA Italy

The use of a broadband, frequency shaped femtosecond laser on translationally cold cesium molecules has recently demonstrated to be a very efficient method of cooling also the vibrational degree of freedom. A sample of cold molecules, initially distributed over several vibrational levels, has thus been transfered into a single selected vibrational level of the singlet X^1∑g ground electronic state. Our method is based on repeated optical pumping by laser light with a spectrum broad enough to excite all populated vibrational levels but limited in its frequency bandwidth with a spatial light modulator. In such a way we are able to eliminate transitions from the selected level, in which molecules accumulate. In this paper we briefly report the main experimental results and then address, in a detailed way by computer simulations, the perspectives for a ＂complete＂ cooling of the molecules, including also the rotational degree of freedom. Since the pumping process strongly depends on the relative shape of the ground and excited potential curves, ro-vibrational cooling through different excited states is theoretically compared.

关键词： cold molecule Optical pumping Pulse .shaping Ultrashort pulse Laser cooling

Towards standardizing retinal optical coherence tomography angiography:a review

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Light(Science & Applications) 2022年第4期11卷 520-541页

作者： danuta m.Sampson Adam m.dubis Fred K.chen Robert J.Zawadzki david d.Sampson Surrey Biophotonics Centre for VisionSpeech and Signal Processing and School of Biosciences and MedicineThe University of SurreyGuildford GU27XHUK NIHR Biomedical Research centre at moorflelds Eye Hospital NHS Trust and UcL Institute of Ophthalmology London EC1V 2PDUK. centre for Ophthalmology and Visual Science(incorporating Lions Eye Institute) The University of Western AustraliaNedlandsWestern Australia 6009Australia. department of Ophthalmology Royal Perth HospitalPerthWestern Australia 6000Australia. Ophthalmology Department of SurgeryUniversity of MelbourneMelbourneVictoria 3002Australia. department of Ophthalmology&Vision Science University of California DavisSacramentoCA 95817USA. Surrey Biophotonics Advanced Technology InstituteSchool of Physics and School of Biosciences and MedicineUniversity of SurreyGuildfordSurrey GU27XHUK

The visualization and assessment of retinal microvasculature are important in the study,diagnosis,monitoring,and guidance of treatment of ocular and systemic *** the introduction of optical coherence tomography angiography(OcTA),it has become possible to visualize the retinal microvasculature volumetrically and without a contrast *** lab-based and commercial clinical instruments,imaging protocols and data analysis methods and metrics,have been applied,often inconsistently,resulting in a confusing picture that represents a major barrier to progress in applying OcTA to reduce the burden of *** data and software sharing,and cross-comparison and pooling of data from different studies are *** inabilities have impeded building the large databases of annotated OcTA images of healthy and diseased retinas that are necessary to study and define characteristics of specific *** paper addresses the steps needed to standardize OcTA imaging of the human retina to address these *** review of the OcTA literature,we identify issues and inconsistencies and propose minimum standards for imaging protocols,data analysis methods,metrics,reporting of findings,and clinical practice and,where this is not possible,we identify areas that require further *** hope that this paper will encourage the unification of imaging protocols in OcTA,promote transparency in the process of data collection,analysis,and reporting,and facilitate increasing the impact of OcTA on retinal healthcare delivery and life science investigations.

关键词： transparency steps inconsistent

Optimized high performance liquid chromatography–ultraviolet detection method using core-shell particles for the therapeutic monitoring of methotrexate

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Journal of Pharmaceutical Analysis 2016年第2期6卷 103-111页

作者： milagros montemurro maría m.de zan juan c.robles Laboratorio de control de calidad de medicamentos Facultad de Bioqufmica y Ciendas Biologicas Universidad Nacional del Litoral Santa Fe Argentina

methotrexate （mTX） is an antineoplastic drug, and due to its high toxicity, the therapeutic drug mon- itoring is strictly conducted in the clinical practice. The chemometric optimization and validation of a high performance liquid chromatography （HPLc） method using core-shell particles is presented for the determination of mTX in plasma during therapeutic monitoring. Experimental design and response surface methodology （RSm） were applied for the optimization of the chromatographic system and the analyte extraction step. A Poroshel1120 ec-c18 （3.0 mm × 75 mm, 2.7 μm） column was used to obtain a fast and efficient separation in a complete run time of 4 min. The optimum conditions for the chroma- tographic system resulted in a mobile phase consisting of acetic acid/sodium acetate buffer solution （85.0 mm, pH =4.00） and 11.2% of acetonitrile at a flow rate of 0.4 mL/min. Selectivity, linearity, accuracy and precision were demonstrated in a range of 0.10-6.0 μm of mTX. The application of the optimized method required only 150μL of patient plasma and a low consumption of solvent to provide rapid re- sults.

关键词： HPLc core-shell particles methotrexate drug monitoring

6 - 10 RFQ design of AdS Project at ImP

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ImP & HIRFL Annual Report 2012年第1期 250-251页

作者： Zhang Zhouli He Yuan Shi Aimin du Xiaonan Liu Yong Li chao Wang Jing Pan Gang Sun Liepeng Zhao Hongwei d. Li S. Virostek m. hoff A. Lambert J. Staples c. Zhang