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Employment of Jacobian elliptic functions for solving problems in nonlinear dynamics of microtubules

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Chinese Physics B 2014年第2期23卷 178-182页

作者： Slobodan Zekovi Annamalai Muniyappan Slobodan Zdravkovi louis Kavitha Institut za nuklearne nauke Vina Laboratorija za atomsku fiziku 040Univerzitet u Beogradu Department of Physics Periyar University Center for Nanoscience and Nanotechnology Periyar University

We show how Jacobian elliptic functions （JEFs） can be used to solve ordinary differential equations （ODEs） describing the nonlinear dynamics of microtubules （MTs）. We demonstrate that only one of the JEFs can be used while the remaining two do not represent the solutions of the crucial differential equation. We show that a kinkbtype soliton moves along MTs. Besides this solution, we also discuss a few more solutions that may or may not have physical meanings. Finally, we show what kind of ODE can be solved by using JEFs.

关键词： Jacobian elliptic functions ordinary differential equations microtubules kink soliton

H2/CO/air premixed and partially premixed flame structure at different pressures based on reaction limit analysis

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Science Bulletin 2018年第19期63卷 1260-1266页

作者： Zaigang Liu Wenjun Kong Jean-louis Consalvi Wenhu Han Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China School of Engineering Sciences. university of Chinese Academy of Sciences Beijing 100049 China IuSTI uMR 7343 Aix-Marseille Universite CNRS Marseille 13453 France

Premixed and partially premixed flames (PPFs) of H2/CO/air syngas are studied numerically to investigate the effect of pressure on syngas PPF structure. Chemical characteristics of the syngas flame at different pressures are investigated based on reaction limit analysis using a one-dimensional configuration. The results show that CO affects the syngas reaction limits through both physical effects that consist mainly in dilution and chemical effects that are related to both R23 (CO+OH=CO2+H) and HCO pathway. In particular, the HCO pathway weakens the flame at low pressures due to the chain-terminating effect of R25 (HCO+O2=CO+HO2) and R26 (HCO+H=CO+H2), and enhances the flame at high pressures because of the contribution of R25 to the HO2chain-branching process. These CO chemical characteristics are also observed in the premixed zone of 50%H2+50%CO syngas PPFs whereas only R23 is important in the non-premixed zone.

关键词： Syngas Partially premixed flame Pressure effect Reaction limit Flame structure

Herbivory of sympatric elk and cattle on Lincoln National Forest,south-central New Mexico

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Forest Ecosystems 2015年第4期2卷 314-326页

作者： Heather H.Halbritter louis C.Bender Extension Animal Sciences and Natural Resources New Mexico State University

Background： Wildlife and livestock grazing are important products of forest ecosystems, but can be controversial. Herbivory by North American elk and domestic cattle is a contentious management issue throughout western North America, often driving management proposals to decrease cattle and elk numbers based on perceived overutilization of forages. Such observations are often site level rather than landscape, and may confuse ecological sustainability with desired conditions. Methods： We used line transects to document vegetation composition, structure, and grazing and browsing utilization for 4 key habitat types： mountain meadows, aspen, thinned conifer, and burned conifer on Lincoln National Forest, New Mexico, uSA. We documented relative habitat use of these types by elk, mule deer, and cattle and modeled relative use on residual grass biomass of mountain meadows and browse utilization of forested types. We determined diets and diet quality of elk and cattle to assess degree of competition. Results： use of grasses in meadows was below management thresholds, and combined elk, cattle, and deer relative habitat use accounted for 〈 14 % of the variance in residual stubble height of Poa protensis, the most abundant grass. Palatable browse was limited in habitat types （〈 107 ***^-1）, use was generally high, and elk presence was correlated with the majority of browsing. Elk and cattle diets did not significantly overlap （Schoener＇s index 0.54-0.57）; elk fed primarily on deciduous shrubs （34 %-55 % of annual diets） and cattle on grass （72 %-77 %）. Digestibility and crude protein levels of cattle diets and body condition of elk indicated high quality diets for cattle and marginal-good quality diets for elk. Conclusions： At observed stocking levels and densities, cattle and elk were not competing for forage based on diet similarity, nor were key habitat types being used beyond sustainable levels. Low browse availability indicates that opportunity exists to increase for

关键词： Browsing Cattle Carrying capacity Elk Grazing Herbivory Nutrition

The effect of total carbon on microscopic soil properties and implications for crop production

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Journal of Arid Land 2012年第3期4卷 251-259页

作者： Inma LEBRON Milton Earl MCGIFFEN Jr Donald louis SuAREZ Centre for Ecology and Hydrology Bangor Gwynedd LL57 2UW UK Department of Botany and Plant Science University of California Riverside CA 92521-0334 USA u.S. Salinity Laboratory Riverside CA 92521-0334 USA

Soil structure is a dynamic property affected by physical, chemical, and microbiological processes. Addition of organic matter to soils and the use of different management practices have been reported to impact soil structure and crop production. Moderation in soil temperature and increases in microbial activity and soil water retention are often suggested as reasons for the rise in crop yield when organic matter is added to the soil. Less is known about the direct effect of changes in soil structure on crop production. A field experiment was conducted to study the effect of summer cover crop and in-season management system on soil structure. The experiment was a nested design with summer cover crop as the main plot and management system as the subplot. Summer cover crop treatments included cowpea （Vigna unguiculata L. Walp.） incorporated into the soil in the fall （CI）, cowpea used as mulch in the fall （CM）, sudangrass （Sorghum vulgare） incorporated into the soil in the fall （S）, and dry fallow or bare ground （B）. Management systems were organic （ORG） and conventional （CNV） systems. Lettuce （Lactuca sativa L.） and cantaloupes （Cucumis melo L.） were cultivated in rotation in the plots for three consecutive years using the same cover crops and management systems for each plot. Disturbed and undisturbed soil cores were collected at the end of the third year and used for laboratory experiments to measure physical, chemical, and hy- draulic properties. Image analysis was used to quantify soil structure properties using a scanning electron micro- scope on thin sections prepared from the undisturbed soil cores. We found that total soil carbon was correlated with porosity, saturation percentage, and pore roughness. Pore roughness was correlated with crop production in gen- eral and with marketable production in particular. We found that the higher the complexity of the pore space, the more water retained in the soil, which may increase soil water residence and reduce plant

关键词： summer cover crop management systems soil structure properties total carbon

GLOBAL WELL-POSEDNESS AND BLOW-uP FOR THE HARTREE EQuATION

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Acta Mathematica Scientia 2017年第4期37卷 941-948页

作者：杨凌燕李晓光吴永洪 louis CACCETTA Sichuan Normal university Chengdu610066China Wuhan Institute of Physics and Machematics Chinese Academy of Science Wuhan 430071China Department of Mathematics and Statistics Curtin University of TechnologyPerthWA 6845Australia

For 2 〈 y 〈 min{4, n}, we consider the focusing Hartree equation iut ＋ Au ＋（｜x｜^-γ ＊｜u｜2）u = O, x∈ R^n Let M[u] and E[u] denote the mass and energy, respectively, of a solution u, and Q be the ground state of - △ ＋ Q = （｜x｜^-γ ＊｜Q｜^2）Q. Guo and Wang [Z. Angew. Math. Phy.,2014] established a dichotomy for scattering versus blow-up for the Cauchy problem of （0,1） if M[u]^l-ScE[u]^Sc 〈 M[Q] ^1-sc E[Q] ^（sc= r-2/2）. In this paper, we consider the complementary case M[u]^1-ScE[u]^sc 〉_ M[Q]^1-sc and obtain a criteria on blow-up and global existence for the Hartree equation （0.1）.

关键词： Hartree equation Threshold criteria blow-up solution

Tumor organoids to study gastroesophageal cancer: a primer

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Journal of Molecular Cell Biology 2020年第8期12卷 593-606页

作者： Ramon u.Jin Jason C.Mills Division of Oncology Department of Internal MedicineWashington University School of MedicineSt.LouisMO 63130USA Division of Gastroenterology Department of Internal MedicineWashington University School of MedicineSt.LouisMO 63130USA Department of Developmental Biology Washington University School of MedicineSt.LouisMO 63130USA Department of Pathology and Immunology Washington University School of MedicineSt.LouisMO 63130USA

Gastroesophageal cancers are leading causes of cancer *** attempts at adopting molecularly based treatment approaches have been slow and ineffective even though we begin to identify specific targetable gene mutations and *** is dear that we should no longer treat all gastroesophageal cancers as a homogeneous disease,which is what we do when we use nonspecific ***,we currently cannot monitor successful gene/pathway targeting,nor understand how/when tumors develop resistance,nor predict which patients will derive maximal *** improve outcomes,we must precisely detail the heterogeneity of these tumors to then individualize cancer therapy as well as develop novel avenues to study and predict treatment effects in individual *** this end,patient-derived organoids,in which tumor cells from individual patients are grown in a Petri dish,are a new versatile system that allows for timely expandability,detailed molecular characterization,and genetic manipulation with the promise of enabling predictive assessment of treatment *** this review,we will explore the development and basic techniques for organoid generation,and discuss the current and potential future applications of this exciting technology to study the basic science of carcinogenesis and to predict/guide cancer patient care in the clinics.

关键词： targeted therapy precision oncology cancer model tumor heterogeneity cancer evolution personalized medicine

Traits uncover quasi-neutral community assembly in a coastal heath vegetation

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Journal of Plant Ecology 2019年第4期12卷 703-712页

作者： JoséLuiz Alves Silva Alexandre Fadigas Souza louis Stephen Santiago Programa de Pós-Graduação em Ecologia Departamento de EcologiaUniversidade Federal do Rio Grande do NorteNatal 59078-970Brazil Departamento de Ecologia Universidade Federal do Rio Grande do NorteNatal 59078-970Brazil Department of Botany and Plant Sciences University of California2150 Batchelor HallRiversideCA 92521USA Smithsonian Tropical Research Institute BalboaAncónPanamáRepublic of Panamá

Aims Trait-based approaches are increasingly being used in ecology due to their potential to explain and predict community structure and dynamic regardless of species ***,we asked whether coastal heath vegetation established in stressful habitats could be assembled by quasi-neutral mechanisms based on functional trait *** are organized through quasi-neutral dynamics if abiotic gradients and/or species interactions impose sorting on functional traits and species performances,but not on species phylogenetic relatedness and *** The study was conducted in a coastal area containing tall dunes near the sea,and relatively flat areas punctuated by short palaeodunes further inland,Northeastern South *** evaluated 10 traits of the 21 most abundant species,as well as eight abiotic variables in 70 plots(25 m^(2))established in dune tops,valleys,flat and steep *** effect of environmental filter was tested by linear mixed models(LMM)between each community-weighted mean(CWM)trait and the abiotic variables,and by two indices of environmental filtering based on intra-and interspecific-trait vari-ability relative to null *** evaluate the effect of species inter-actions,we used an index of niche overlap relative to null models,and LMMs between this index and the species richness of *** Findings The environmental filtering index did not deviate from null expect-ations for any *** that included individual variability per-formed similarly to models that used species mean ***,the explicit consideration of environmental gradients by CWM ana-lyses revealed functional patterns that would remain undetected if trait distribution was analyzed *** addition,intraspecific vari-ation in the stem length was an important driver of species diversity as suggested by the relationship between species richness and the niche overlap *** on the occurrence and phylogenetic re-latedness o

关键词： Restinga heath vegetation harsh environment stress-tolerant species response traits

Differences in Pandemic-Related Factors Associated with Alcohol and Substance use among Korean Adolescents:Nationwide Representative Study

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Biomedical and Environmental Sciences 2023年第6期36卷 542-548页

作者： Hyunju Yon Sangil Park Jung u Shin Ai Koyanagi louis Jacob Lee Smith Chanyang Min Jinseok Lee Rosie Kwon Guillaume Fond Laurent Boyer Sunyoung Kim Namwoo Kim Sang Youl Rhee Jae Il Shin Dong Keon Yon Ho Geol Woo Department of Medicine Kyung Hee University College of MedicineSeoulRepublic of Korea Department of Neurology Kyung Hee University Medical CenterSeoulRepublic of Korea Department of Dermatology CHA Bundang Medical CenterCHA University School of MedicineSeongnamRepublic of Korea Research and Development unit Parc Sanitari Sant Joan de DeuCIBERSAMISCIIIBarcelonaSpain Catalan Institution for Research and Advanced Studies(ICREA) Pg.Lluis CompanysBarcelonaSpain Department of Physical Medicine and Rehabilitation Lariboisière-Fernand Widal HospitalAP-HPUniversity Paris CitéParisFrance Centre for Health Performance and WellbeingAnglia Ruskin UniversityCambridgeUK Center for Digital Health Medical Science Research InstituteKyung Hee University Medical CenterKyung Hee University College of MedicineSeoulRepublic of Korea Department of Biomedical Engineering Kyung Hee UniversityYonginRepublic of Korea Assistance Publique-Hôpitaux de Marseille(AP-HM) Aix-Marseille UniversityCEReSSHealth Service Research and Quality of Life CenterMarseilleFrance FondaMental Foundation CreteilFrance Department of Family Medicine Kyung Hee University College of MedicineSeoulRepublic of Korea Department of Psychiatry Seoul St.Mary's HospitalThe Catholic University of KoreaCollege of MedicineSeoulRepublic of Korea Department of Endocrinology and Metabolism Kyung Hee University School of MedicineSeoulRepublic of Korea Department of Pediatrics Yonsei University College of MedicineSeoulRepublic of Korea Department of Pediatrics Kyung Hee University College of MedicineSeoulRepublic of Korea

The coronavirus disease 2019(COVID-19)pandemic has raised concerns about the mental health and social well-being of youth,including its potential to increase or exacerbate substance use behaviors[1].Among adolescents,the COVID-19pandemic has resulted in limited face-to-face school contact and thus missed milestones in preventing alcohol and substance use.

关键词： Alcohol raised alcohol

PREDICTING HuMAN DRuG SAFETY FROM ANIMAL STuDIES: CuRRENT ISSuES

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中国临床药理学杂志 1987年第3期 144-155页

作者： louis Lasagna Center for the Study of Drug Development and Sackler School of Graduate Biomedical Sciences Tufts university Boston.u.S.A. M.D.

There is no disagreement about the desirability of minimizing hazards to human health deriving from chemicals,be they pharmaceutical,industrial,or agricultural *** the exception of some

关键词： CuRRENT ISSuES PREDICTING HuMAN DRuG SAFETY FROM ANIMAL STuDIES