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Oxidative Stress in Collegiate Cross Country Skiers in Mid- and Post-Seasons

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j.urnal of Biosciences and Medicines 2024年第5期12卷 99-110页

作者： Scott P. j.rome Kriya L. Dunlap Ava M. Parrish Matthew L. Lowman Emily M. Shipman lawrence K. Duffy Arleigh j. Reynolds Department of Chemistry & Biochemistry University of Alaska Fairbanks Fairbanks AK USA Institute of Arctic Biology University of Alaska Fairbanks Fairbanks AK USA Department of Biology & Wildlife University of Alaska Fairbanks Fairbanks AK USA Department of Veterinary Medicine University of Alaska Fairbanks Fairbanks AK USA

Purpose: The oxidative stress (OS) hypothesis of overtraining syndrome argues that increased production of free radicals through exercise cause muscle fatigue and damage resulting in lower athletic performance. Several studies have investigated OS immediately before and after exercise bouts in a training macrocycle. Our study aimed to compare OS of endurance athletes between a competition macrocycle and the immediate post-season recovery macrocycle. In addition, we aimed to identify athletes who experienced an unexplainable drop in athletic performance during the competition season in order to compare their OS to those who experienced no drop in performance. Methods: Fifteen members of the University of Alaska Fairbanks cross country ski team volunteered for this study. Blood samples were taken in early February (“mid-season”) and late April (“post-season”). Participants completed questionnaires regarding physical activity and athletic performance at the time of the blood draws. Plasma was analyzed for 4-hydroxynonenal (HNE), nitrotyrosine, nitric oxide (NOX), and superoxide dismutase (SOD). Significance was determined by Wilcoxon and Mann-Whitney tests. Results: Participants displayed significantly higher (p Conclusion: Signs of oxidative stress and mitigation during the post-season recovery macrocycle were higher in athletes who reported experiencing a drop in athletic performance during the competition season macrocycle.

关键词： Oxidative Stress 4-Hydroxynonenal Superoxide Dismutase Athletic Performance Training Macrocycle

The pollen tube clear zone: Clues to the mechanism of polarized growth

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j.urnal of Integrative Plant Biology 2015年第1期57卷 79-92页

作者： Peter K.Hepler lawrence j.winship Biology Department University of Massachusetts School of Natural Science Hampshire College

Pollen tubes usually exhibit a prominent region at their apex called the ＂clear zone＂ because it lacks light refracting amyloplasts. A robust, long clear zone often associates with fast growing pollen tubes, and thus serves as an indicator of pollen tube health. Nevertheless we do not understand how it arises or how it is maintained. Here we review the structure of the clear zone, and attempt to explain the factors that contribute to its formation. While amyloplasts and vacuolar elements are excluded from the clear zone, virtually all other organelles are present including secretory vesicles, mitochondria, Golgi dictyosomes, and the endoplas-mic reticulum （ER）. Secretory vesicles aggregate into an inverted cone appressed against the apical plasma membrane. ER elements move nearly to the extreme apex, whereas mitochondria and Golgi dictyosomes move less far forward. The cortical actin fringe assumes a central position in the control of clear zone formation and maintenance, given its role in generating cytoplasmic streaming. Other likely factors include the tip-focused calcium gradient, the apical pH gradient, the influx of water, and a host of signaling factors （small G-proteins）. We think that the clear zone is an emergent property that depends on the interaction of several factors crucial for polarized growth.

关键词： Actin endoplasmic reticulum myosin polarized growth pollen tube

Calcium at the Cell Wall-Cytoplast Interface

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j.urnal of Integrative Plant Biology 2010年第2期52卷 147-160页

作者： Peter K.Hepler lawrence j.winship Department of Biology University of MassachusettsAmherstMA 01003USA School of Natural Science Hampshire CollegeAmherstMA 01002USA

Attention is given to the role of Ca^2＋ at the interface between the cell wall and the cytoplast, especially as seen in pollen tubes. While the cytoplasm directs the synthesis and deposition of the wall, it is less well appreciated that the wall exerts considerable self control and influences activities of the cytoplasm. Ca^2＋ participates as a crucial factor in this two way communication. In the cytoplasm, a [Ca^2＋] above 0.1 μM, regulates myriad processes, including secretion of cell wall components. In the cell wall Ca^2＋ , at 10μM to 10 mM, binds negative charges on pectins and imparts structural rigidity to the wall. The plasma membrane occupies a pivotal position between these two compartments, where selective channels regulate influx of Ca^2＋ , and specific carriers pump the ion back into the wall. In addition we draw attention to different factors, which either respond to the wall or are present in the wall, and usually generate elevated[Ca^2＋ ] in the cytoplasm. These factors include：（i） stretch activated channels; （ii） calmodulin; （iii） annexins; （iv） wall associated kinases; （v） oligogalacturonides; and （vi） extracellular adenosine 5＇-triphosphate. Together they provide evidence for a rich and multifaceted system of communication between the cytoplast and cell wall, with Ca^2＋ as a carrier of information.

关键词： Calcium at the Cell Wall-Cytoplast Interface CNGC

Associations of self-reported and device-assessed physical activity with fatigue,quality of life,and sleep quality in adults living with and beyond cancer

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j.urnal of Sport and Health Science 2023年第6期12卷 664-673,F0003页

作者： Phillippa Lally Natalie Ella Miller Claire lawrence Rebecca j.Beeken Abigail Fisher Department of Behavioural Science and Health University College LondonLondon WC1E 6BTUK Department of Psychology University of SurreyGuildford GU27XHUK Leeds Institute of Health Sciences Leeds LS29NLUK

Background Greater physical activity is associated with improved outcomes in people living with and beyond ***,most studies in exercise oncology use self-reported measures of physical *** have explored agreement between self-reported and device-based measures of physical activity in people living with and beyond *** study aimed to describe physical activity in adults affected by cancer across self-reported and device-assessed activity,to explore levels of agreement between these measures in terms of their utility for categorizing participants as meeting/not meeting physical activity guidelines,and to explore whether meeting guidelines is associated with fatigue,quality of life,and sleep *** A total of 1348 adults living with and beyond cancer from the Advancing Survivorship Cancer Outcomes Trial completed a survey assessing fatigue,quality of life,sleep quality,and physical *** Godin-Shephard Leisure-Time Physical Activity Questionnaire was used to calculate a Leisure Score Index(LSI)and an estimate of moderate-to-vigorous physical activity(MVPA).Average daily steps and weekly aerobic steps were derived from pedometers worn by *** The percentage of individuals meeting physical activity guidelines was 44.3%using LSI,49.5%using MVPA,10.8%using average daily steps,and 28.5%using weekly aerobic ***(Cohen'sκ)between self-reported and pedometer measures ranged from 0.13(LSI *** daily steps)to 0.60(LSI ***).After adj.sting for sociodemographic and health-related covariates,meeting activity guidelines using all measures was associated with not experiencing severe fatigue(odds ratios(ORs):1.43–1.97).Meeting guidelines using MVPA was associated with no quality-of-life issues(OR=1.53).Meeting guidelines using both self-reported measures were associated with good sleep quality(ORs:1.33–1.40).Conclusion Less than half of all adults affected by cancer are meeting physical activity guidelines,

关键词： Cancer survivorship Fatigue Physical activity Quality of life SleepTagedAPTARAEnd

Improved prediction of clay soil expansion using machine learning algorithms and meta-heuristic dichotomous ensemble classifiers

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Geoscience Frontiers 2022年第1期13卷 268-284页

作者： E.U.Eyo S.j.Abbey T.T.lawrence F.K.Tetteh Department of Geography and Environmental Management University of the West of EnglandBristolUnited Kingdom Research Centre for Fluid and Complex Systems Coventry UniversityCoventryUnited Kingdom Department of Civil Engineering University of BirminghamBirminghamUnited Kingdom

Soil swelling-related disaster is considered as one of the most devastating geo-hazards in modern ***,proper determination of a soil’s ability to expand is very vital for achieving a secure and safe ground for ***,this study has provided a novel and intelligent approach that enables an improved estimation of swelling by using kernelised machines(Bayesian linear regression(BLR)&bayes point machine(BPM)support vector machine(SVM)and deep-support vector machine(D-SVM));(multiple linear regressor(REG),logistic regressor(LR)and artificial neural network(ANN)),tree-based algorithms such as decision forest(RDF)&boosted trees(BDT).Also,and for the first time,meta-heuristic classifiers incorporating the techniques of voting(VE)and stacking(SE)were *** independent scenarios of explanatory features’combination that influence soil behaviour in swelling were *** results indicated BLR as possessing the highest amount of deviation from the predictor variable(the actual swell-strain).REG and BLR performed slightly better than ANN while the meta-heuristic learners(VE and SE)produced the best overall performance(greatest R2 value of 0.94 and RMSE of 0.06%exhibited by VE).CEC,plasticity index and moisture content were the features considered to have the highest level of *** binary classifiers(SVM,D-SVM and BPM)gave better accuracy(average accuracy and recall rate of 0.93 and 0.60)compared to ANN,LR and ***-driven diagnostic test indicated that the meta-heuristic models’best performance occurred when ML training was conducted using k-fold validation ***,it is recommended that the concepts developed herein be deployed during the preliminary phases of a geotechnical or geological site characterisation by using the best performing meta-heuristic models via their background coding resource.

关键词： Artificial neural networks Machine learning Clays Algorithm Soil swelling Soil plasticity

Simulated Microbe Removal around Finger Rings Using Different Hand Sanitation Methods

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International j.urnal of Oral Science 2009年第3期1卷 136-142页

作者： Archana A. Alur Madhavi j. Rane j.mes P. Scheetz Douglas j. Lorenz lawrence Gettleman Ballard High School Louisville Kentucky USA School of Medicine University of Louisville Louisville Kentucky USA School of Dentistry University of Louisville Louisville Kentucky USA School of Public Health & Information Sciences University of Louisville Louisville Kentucky USA

Aim It is our opinion that the CDC and the WHO have underestimated cross-contamination under examination gloves in dental clinics while wearing j.welry, such as finger rings. These agencies only ＂recommend＂ removing j.welry, and only washing hands for 15 seconds with soap and warm water before donning gloves. This study examined several washing procedures and finger rings using simulated microbes. Methodology A gloved robber hand manikin was made and fitted with a flesh disposable vinyl glove. Four fingers were fitted with rings or no ring, dusted with simulated microbes, and washed with a scrub brush for 5, 15, and 25 seconds under 20℃ and 40℃ water alone, or with liquid hand soap. Light levels （in lux） of fluorescent powder before and after washing were measured and delta scores calculated for changes in light levels, equivalent to effectiveness of hand washing procedures. A full-factorial, 3-factor analysis of variance （ANOVA） was used to test for differences among levels of the three study factors-time, temperature, and soap use. Tukey＇s post hoc honestly significant difference （HSD） test was applied to significant factors to examine pair-wise differences between factor levels. Results It was found that the longer the hands with rings were washed with a scrub brush under flowing water, the more simulated microbes were removed. By 25 seconds, all methods were essentially the same. Simulated microbes were more difficult to remove from the palm compared to the back of the hand. The liquid hand soap used in this study was more effective with warm water than cold. When given a choice of washing with cold water up to 15 seconds, it would be preferable not to use soap to remove simulated microbes. Qualitatively, the outer surface of finger rings were more effectively cleaned than the crevice below the ring, and the ring with a stone setting appeared to accumulate and retain simulated microbes more than other rings. Conclusion The most effective treatment was washing wi

关键词： dental exam gloves finger ring j.welry crosscontamination hand hygiene microbes fluorescent powder dental health care workers

Performance and calibration of quark/gluon-j.t taggers using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAS detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling N.j. Abicht S.H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B.S. Acharya C. Adam Bourdarios L. Adamczyk S.V. Addepalli M.j. Addison j. Adelman A. Adiguzel T. Adye A.A. Affolder Y. Afik M.N. Agaras j. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad F. Ahmadov W.S. Ahmed S. Ahuj. X. Ai G. Aielli A. Aikot M. Ait Tamlihat B. Aitbenchikh I. Aizenberg M. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar K. Al Khoury G.L. Alberghi j. Albert P. Albicocco G.L. Albouy S. Alderweireldt M. Aleksa I.N. Aleksandrov C. Alexa T. Alexopoulos F. Alfonsi M. Algren M. Alhroob B. Ali H.M.j. Ali S. Ali S.W. Alibocus M. Aliev G. Alimonti W. Alkakhi C. Allaire B.M.M. Allbrooke j.F. Allen C.A. Allendes Flores P.P. Allport A. Aloisio F. Alonso C. Alpigiani M. Alvarez Estevez A. Alvarez Fernandez M. Alves Cardoso M.G. Alviggi M. Aly Y. Amaral Coutinho A. Ambler C. Amelung M. Amerl C.G. Ames D. Amidei S.P. Amor Dos Santos K.R. Amos V. Ananiev C. Anastopoulos T. Andeen j.K. Anders S.Y. Andrean A. Andreazza S. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel M.T. Anthony E. Antipov M. Antonelli F. Anulli M. Aoki T. Aoki j.A. Aparisi Pozo M.A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal S.j. Arbiol Val C. Arcangeletti A.T.H. Arce E. Arena j.F. Arguin S. Argyropoulos j.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai S. Asai N.A. Asbah j. Assahsah K. Assamagan R. Astalos S. Atashi R.j. Atkin M. Atkinson H. Atmani P.A. Atmasiddha K. Augsten S. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia M. Bahmani A.j. Bailey V.R. Bailey j.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E.M. Baldin P. Balek E. Ballabene F. Balli L.M. Baltes W.K. Balunas j. Balz E. Banas M. Bandieramonte A. Bandyopadhyay S. Bansal L. Barak M. Barakat E.L. Barberio D. Barberis M. Barbero M.Z. Barel K.N. Barends T. Barillari M-S. Barisits T. Barklow P. Baron D.A. Baron Mo The ATLAS Collaboration

The identification of j.ts originating from quarks and gluons,often referred to as quark/gluon tagging,plays an important role in various analyses performed at the Large Hadron Collider,as Standard Model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced *** paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAS Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb^(-1) collected by the ATLAS *** taggers with high performances in rej.cting j.ts from gluon over j.ts from quarks are studied:one tagger is based on requirements on the number of inner-detector tracks associated with the j.t,and the other combines several j.t substructure observables using a boosted decision tree.A method is established to determine the quark/gluon fraction in data,by using quark/gluon-enriched subsamples defined by the j.t *** in tagging efficiency between data and simulation are provided for j.ts with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

关键词： ATLAS j.T QUARK GLUON TAGGING

Design　Issues　for　Use　of　Solid　State　Transmitter　Radars　in　the　Terminal　Airspace

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j.urnal of Systems Engineering and Electronics 1995年第1期6卷 57-64页

作者： E. Lee Cole & lawrence j. Friz(Westinghouse Electric Corporation, Baltimore, MD, USA) Westinghouse Electric Corporation Baltimore MD USA

This paper focuses on the issues of introducing a SSTx ASR into the terminal environment. The primary concern is the waveform and the sidelobe resolution issues that result. The key waveform requirements were derived and presented along with the identification of the design parameters that impact the new Westinghouse radar's design. Performance of the FAA's premier terminal radar, the Westinghouse ASR-9, was used as the requirements bench mark. A properly designed SSTx ASR will provide the same aircraft and weather detection capabilities, and provide the false target rej.ction performance that presently exists within the ASR-9. The paper concludes with a brief view of the Modular ASR (MODASR), SSTx ASR presently in development at Westinghouse. Converting the Klystron tube ASR-9 into an equivalent SSTx radar involves maj.r changes to almost every subassembly to satisfactorily address critical issues presented within this paper.

关键词： Design Use Issues Airspace

principles of Managerial Finance 10th ed.

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