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Myocardial contraction maps using tissue Doppler acceleration imaging

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Chinese Medical Journal 2000年第8期113卷 91-96页

作者：尹立雪 Marek belohlavek Douglas L.Packer james F.Greenleaf james b.Seward Division of Cardiovascular Diseases and Internal Medicine Mayo Clinic Mayo Foundation Rochester Minnesota USA. yinlixue@***

ObjectiveTo evaluate the tissue Doppler acceleration imaging(TDAI)data which can be used to determine the intramural site of origin of myocardial contraction in response to electrical stimulation.MethodsSix open-chest pigs with left ventricle(LV)pacing were evaluated with TDAI. An epicardial surface scanning method was used to collect short-axis views of the left ventricle. The electrode was implanted from the epicardium through the anterior free wall to an intramural position.ResultsDuring pacing, the intramural onset of myocardial acceleration occurred within 33 ms after electrical stimulation and always surrounded the embedded subendocardial end of the pacing needle. The observed short-axis diameter of the area of initial myocardial acceleration ranged from 2.9 mm to 5.0 mm(4.2±0.9 mm, n = 6). The onset of myocardial acceleration allowed appreciation of the initial intramural myocardial contraction. The spatial size and acceleration magnitude of the initial myocardial acceleration distribution were irregular.ConclusionTwo-dimensional myocardial acceleration mapping can show the intramural site of origin of myocardial contraction in response to paced electrical stimulation. The location of myocardial acceleration conformed to the site of initial electrical stimulation. The delay to the earliest regional myocardial contraction, 33 ms after paced electrical stimulation, was related to the frame rate of image acquisition. Chin Med J 2000; 113(8): 763-768

关键词： electrical pacing myocardial contraction tissue Doppler acceleration imaging

Sporophytic nondisjunction of the maize b chromosome at high copy numbers

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Journal of Genetics and Genomics 2010年第1期37卷 79-84页

作者： Rick E.Masonbrink james A.birchler Division of biological Sciences University of Missouri

It has been known for decades that the maize b chromosome undergoes nondisjunction at the second pollen *** in-situ hybridization （FISH） was used to undertake a quantitative study of maize plants with differing numbers of b chromosomes to observe if instability increases by increasing b dosage in root tip tissue.b chromosome nondisjunction was basically absent at low copy number,but increased at higher b ***,b nondisjunction rates are dependent on the dosage of b＇s in the *** in nondisjunction were also documented between odd and even doses of the *** plants that have inherited odd numbered doses of the b chromosome,b loss is nearly twice as likely as b gain in a somatic *** comparing plants with even doses of b＇s to plants with odd doses of b＇s,plants with even numbers had a significantly higher chance to increase in ***,the b＇s nondisjunctive capacity,previously thought to be primarily restricted to the gametophyte,is present in sporophytic cells.

关键词： maize Zea mays b chromosome nondisjunction odd-even effect

The Einstein-Scalar Field Constraints on Asymptotically Euclidean Manifolds

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Chinese Annals of Mathematics,Series b 2006年第1期27卷 31-52页

作者： Yvonne CHOQUET-bRUHAT james ISENbERG Daniel POLLACK Dedicated to the memory of Shiing-Shen Chern

by using the conformal method, solutions of the Einstein-scalar ficld gravitational constraint equations are obtained. Handling scalar fields is a bit more challenging than handling matter fields such as fluids, Maxwell fields or Yang-Mills fields, because the scalar field introduces three extra terms into the Lichnerowicz equation, rather than just one. The proofs are constructive and allow for arbitrary dimension （〉 2） as well as low regularity initial data.

关键词： Einstein-scalar field Constraints Asymptotically Euclidian

Convergence to a Single Wave in the Fisher-KPP Equation(Dedicated to Haim brezis,with admiration and respect)

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Chinese Annals of Mathematics,Series b 2017年第2期38卷 629-646页

作者： james NOLEN Jean-Michel ROQUEJOFFRE Lenya RYZHIK Department of Mathematics Duke UniversityDurhamNC 27708USA Institut de Mathématiques(UMR CNRS 5219) Université Paul Sabatier118 route de Narbonne31062 Toulouse cedexFraxlce Department of Mathematics Stanford UniversityStanford CA94305USA.

The authors study the large time asymptotics of a solution of the Fisher-KPP reaction-diffusion equation, with an initial condition that is a compact perturbation of a step function. A well-known result of bramson states that, in the reference frame moving as 2t-(3/2 )log t+x∞, the solution of the equation converges as t → +∞ to a translate of the traveling wave corresponding to the minimal speed c_* = 2. The constant x∞ depends on the initial condition u(0, x). The proof is elaborate, and based on probabilistic *** purpose of this paper is to provide a simple proof based on PDE arguments.

关键词： Traveling waves, KPP, Front propagation, Asymptotic analysis,Reaction-diffusion

Molecular behavior of the aptamer HJ24 self-assembled on highly oriented pyrolytic graphite(HOPG)

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Science China Chemistry 2015年第12期58卷 1858-1865页

作者： Xueqin Zhao Yishun Huang Chaoyong james Yang bingwei Mao College of Life Sciences Zhejiang Sci-Tech University State Key Laboratory of Physical Chemistry of the Solid Surfaces

Nucleic acid sensing analysis has been widely applied to the fields of food quality control, environmental monitoring, and medical diagnosis. A key step in developing effective DNA-based electrochemical biosensors is to obtain a biorecognition layer on the biosensor, which can be influenced by many factors. Hence, we constructed a series of HJ24 layers on highly oriented pyrolytic graphite to investigate the relation between the configuration of the adsorbed probe HJ24 and the redox property using atomic force microscopy and voltammetry. We used HJ24 for its diagnostic value as it specifically recognizes the SH2 domain-containing phosphatase, a critical contributor in many important signaling pathways. The results demonstrated that increasing K ions induced G-quartet oxidation peak occurrence/increase([K+]?400 mmol/L), and also resulted in the formation of more compact single strand sheets([K+]?300 mmol/L). Moreover, transitions of molecule configurations and redox currents of G-quartets were observed at low concentration [K+]=12 mmol/L, which may indicate the appearance of new configurations under this condition. besides, by analyzing atomic force microscopy(AFM) images, it was found that the different adsorbed configurations are correlated with the HJ24 concentration, the basal configuration, and the linker group on the HJ24 sequence. This information may be useful for understanding the adsorption process of HJ24 as well as for the further development of practical applications for HJ24 films on DNA electrochemical sensors, and may ultimately help improve the diagnosis and treatment of patients with SHP2-related diseases.

关键词： self-assembly G-quadruplex DNA SHP2 Atomic force microscopy HOPG

Projecting the global impact of fossil fuel production from the Former Soviet Union

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International Journal of Coal Science & Technology 2021年第6期8卷 1208-1226页

作者： Steve Mohr Jianliang Wang james Ward Damien Giurco The University of Newcastle University DriveCallaghanNSW 2308Australia School of business Administration China University of PetroleumBeijingChina Engineering and the Environment University of South AustraliaMawson Lakes CampusMawson Lakes BoulevardMawson LakesSA 5095Australia Institute for Sustainable Futures University of Technology SydneyUTS Building 10235 Jones St.UltimoNSW 2007Australia

Detailed projections of the Former Soviet Union(FSU)fossil fuel production has been *** production has been modelled at the region(oblast)level where *** projections were made using the Geologic Resource Supply-Demand Model(GeRS-DeMo).Low,best Guess and High scenarios were *** fossil fuels are projected to peak between 2027 and 2087 with the range due to spread of Ultimately Recoverable Resources(URR)values *** best Guess(bG)scenario anticipates FSU will peak in 2087 with production over 170 EJ per *** FSU projections were combined with rest of the world projections(Mohr et al.2015b),the emissions from the High scenario for the world are similar to the IPCC A1 AIM scenario.

关键词： Former Soviet Union Fossil Fuel Production Fossil Fuel Projection

Skeletal Muscle Fiber Type and Morphology in a Middle-Aged Elite Male Powerlifter Using Anabolic Steroids

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Journal of Science in Sport and Exercise 2021年第4期3卷 404-411页

作者： Steven b.Machek Kent A.Lorenz Marialice Kern Andrew J.Galpin james R.bagley Muscle Physiology Laboratory Department of KinesiologyCollege of Health and Social SciencesSan Francisco State University1600 Holloway AvenueGym 101San FranciscoCA 94132USA Exercise and biochemical Nutrition Laboratory Department of HealthHuman Performanceand RecreationRobbins College of Health and Human SciencesBaylor UniversityWacoTXUSA biochemistry and Molecular Exercise Physiology Laboratory Center for Sport PerformanceCalifornia State UniversityFullertonUSA

Powerlifting regularly exposes athletes to extreme stimuli such as chronic heavy resistance training(HRT),and many powerlifters choose to augment their performance with anabolic-androgenic steroids(AAS).However,little is known about the myocellular adaptations that occur from long-term HRT and AAS use,especially into middle *** were presented with the unique opportunity to study muscle cells from an elite-level powerlifter(EPL;age 40 years)with≥30 years of HRT experience and≥15 years of AAS *** purpose of this case study was to identify myocellular characteristics[myosin heavy chain(MHC)fiber type,fiber size,and myonuclear content]in EPL,as well as compare these data to existing *** participant underwent a resting vastus lateralis muscle biopsy and single fibers were analyzed for MHC content via SDS-PAGE.A subset of fibers underwent MHC-specific imaging analysis via confocal microscopy to identify cell size(cross-sectional area,CSA)and myonuclear domain(MND)*** fiber type distribution was 9% I,12% I/IIa,79% IIa,and 0% other *** pure MHC IIa(fast-twitch)fiber content was amongst the highest reported in the *** analysis of MHC IIa fibers revealed a mean CSA of 4218±933μm^(2) and MND of 12,548±3181μm^(3).While the fast-twitch fiber CSA was comparable to values in previous literature,mean MND was smaller than has been reported in untrained men,implying greater capacity for growth and *** findings showcase the unique muscle cell structure of an elite powerlifter,extending the known physiological limits of human muscle size and strength.

关键词： Resistance training Myonuclear domain Myonuclei Myosin heavy chain Confocal microscopy Muscle biopsy

Seasonal Variability of biofouling Community Structure in the Gulf of Mannar,Southeast Coast of India:A Multivariate Approach

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Journal of Ocean University of China 2023年第3期22卷 766-776页

作者： MARIMUTHU Nithyanandam WILSON james Jerald KUMARAGURU Arumugam Kuppuswamy Department of Marine and Coastal Studies School of EnergyEnvironment and Natural ResourcesMadurai Kamaraj UniversityMadurai 625021India Zoological Survey of India Fire-Proof Spirit BuildingIndian Museum ComplexKolkata 700016West BengalIndia Noorul Islam Center for Higher Education KumaracoilThuckalayKanyakumari District 629180Tamil NaduIndia

In this research,an Underwater biofouling Panel(UWbFP)system was erected for the qualitative and quantitative estimation of macro fouling organisms in the Gulf of ***-four biofoulers were identified from four types of selected test *** these biofoulers,Amphibalanus amphitrite(Darwin,1854)was the dominant *** concrete panel encouraged the highest barnacle density compared to the other *** series of test panels were used to assess the seasonal density of biofouling *** overall variation in barnacle count in the seaward and shoreward sides of all these three series were *** were found to be significantly different from each *** greater variations in the barnacle density observed in this study in A-series of test panels could be due to the lack of or absence of other foulers to compete within the *** Shannon-Wiener species diversity index showed the highest diversity in wood substratum among the three series with greater accumulation of different types of fouling *** analyses were also performed to understand the seasonal variation as well as the settlement pattern on the different directions of test panels based on validated *** showed a strong variability(PC1 between 70.8%and 98.6%variance)between the directions of the panels in connection with barnacle *** shade plot and CAP analysis segregated the short-term A-series test panels from the long-term(b-and C-series)test ***,the output was helpful in understanding the recruitment status of various faunal resources involved in the biofouling processes.

关键词： biofouling barnacle hard fouler multivariate analysis fouling biomass Gulf of Mannar

RASSF1A IS A TUMOR SUPPRESSOR GENE IN MELANOMA THROUGH MEDIATING APOPTOSIS,CELL CYCLE PROGRESSION AND INHIbITION OF AKT/P70S6K/EIF4E SIGNAL PATHWAY

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RASSF1A IS A TUMOR SUPPRESSOR GENE IN MELANOMA THROUGH MEDIA...