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Chinese Journal of Oceanology and Limnology 2011年第4期29卷 724-738页

作者： Patricia m. GLIBERT JoAnn m. BURKHOLDER University of maryland Center for Environmental Science Horn Point Laboratory PO Box 775 Cambridge MD 21613 USA Center for Applied Aquatic Ecology North Carolina State University Raleigh NC 27606 USA

While many harmful algal blooms have been associated with increasing eutrophication, not all species respond similarly and the increasing challenge, especially for resource managers, is to determine which blooms are related to eutrophication and to understand why particular species proliferate under specific nutrient conditions. The overall goal of this brief review is to describe why nutrient loads are not changing in stoichiometric proportion to the "Redfield ratio", and why this has important consequences for algal growth. many types of harmful algae appear to be able to thrive, and/or increase their production of toxins, when nutrient loads are not in proportion classically identified as Redfield ratios. Here we also describe some of the physiological mechanisms of different species to take up nutrients and to thrive under conditions of nutrient imbalance.

关键词： HABs mixotrophy nitrogen nutrient loading nutrient ratios nutrient stoichiometry organicnutrients phosphorus

Dynamics of a Rational Difference Equation

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Chinese Annals of mathematics,Series B 2009年第2期30卷 187-198页

作者： Elmetwally m. ELABBASY Elsayed m. ELSAYED Department of mathematics Faculty of Science Mansoura University

The authors investigate the global behavior of the solutions of the difference equation xn＋1=axn-1xn-k/bxn-p＋cxn-q,n=0,1,…where the initial conditions x-r, x-r＋1, x-r＋2,… , x0 are arbitrary positive real numbers, r = max{l, k,p, q） is a nonnegative integer and a, b, c are positive constants. some special cases of this equation are also studied in this paper.

关键词： Stability Periodic solutions Difference equations

Quantum phase distribution and the number-phase Wigner function of the generalized squeezed vacuum states associated with solvable quantum systems

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Chinese Physics B 2012年第5期21卷 265-273页

作者： G.R.Honarasa m.K.Tavassoly m.Hatami Department of Physics Faculty of ScienceShiraz University of Technology Atomic and molecular Group Faculty of PhysicsYazd University

The quantum phase properties of the generalized squeezed vacuum states associated with solvable quantum systems are studied by using the Pegg-Barnett ***,two nonclassical features,i.e.,squeezing in the number and phase operators,as well as the number-phase Wigner function of the generalized squeezed states are *** to some actual physical situations,the present approach is applied to two classes of generalized squeezed states：solvable quantum systems with discrete spectra and nonlinear squeezed states with particular nonlinear ***,the time evolution of the nonclassical properties of the considered systems has been numerically investigated.

关键词： squeezed vacuum states solvable quantum systems phase distribution number phaseWigner function

New exotic charmonium states

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Chinese Physics C 2010年第9期34卷 1157-1162页

作者： m.Nielsen Instituto de Física Universidade de So Paulo

In the last years many states in the charmonium mass region were discovery by BABAR,Belle and CDF collaborations.I discuss some of these discoveries,and how the QCD Sum Rule approach can be used to understand the stru... 详细信息

关键词： non-perturbative methods heavy mesons spectroscopy exotic mesons

Biomarker and animal models for assessment of retinoid efficacy in cancer chemoprevention

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Acta Pharmacologica Sinica 2007年第9期28卷 1383-1391页

作者： Richard m NILES Department of Biochemistry and microbiology Joan C Edwards School of MedicineMarshall UniversityHuntingtonWV 25701USA

Vitamin A is essential for normal growth and *** andlaboratory studies suggest that decreased vitamin A levels and defective metabo-lism/action may contribute to the genesis of certain *** on thisinformation,natural and synthetic derivatives of vitamin A (retinoids) have beenused for chemoprevention of *** have had some success in thechemoprevention of leukoplakia and in the decreased incidence of second prima-ries in head and neck *** is little information on biomarkers that can beused to assess the efficacy of the chemopreventive activity of *** of retinoids to induce RARb has been consistently shown to correlate withthe response of cells and tissues to retinoic acid,but few other biomarkers havebeen certified as indicators of retinoid *** light of the failure of the ATBCand CARET clinical intervention trials for chemoprevention of lung cancer,greateruse of animal models for chemoprevention studies is *** potentialcombination of phytochemicals that inhibit DNA methyltransferase activity withretinoids holds promise for more effective chemoprevention of retinoid-unrespon-sive premalignant lesions.

关键词： vitamin A retinoic acid chemoprevention biomarkers animal models transgenic animals

Bright, periodic, compacton and bell-shape soliton solutions of the extended QZK and (3+1)-dimensional ZK equations

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Communications in Theoretical Physics 2021年第10期73卷 23-35页

作者： m Ali Akbar md Abdul Kayum m S Osman Department of Applied mathematics University of RajshahiBangladesh Department of Computer Science&Engineering North Bengal International UniversityRajshahiBangladesh Department of mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt

The(3+1)-dimensional Zakharov–Kuznetsov(ZK) and the new extended quantum ZK equations are functional to decipher the dense quantum plasma, ion-acoustic waves, electron thermal energy,ion plasma, quantum acoustic waves, and quantum Langmuir waves. The enhanced modified simple equation(EmSE) method is a substantial approach to determine competent solutions and in this article, we have constructed standard, illustrative, rich structured and further comprehensive soliton solutions via this method. The solutions are ascertained as the integration of exponential, hyperbolic,trigonometric and rational functions and formulate the bright solitons, periodic, compacton, bellshape, parabolic shape, singular periodic, plane shape and some new type of solitons. It is worth noting that the wave profile varies as the physical and subsidiary parameters change. The standard and advanced soliton solutions may be useful to assist in describing the physical phenomena previously mentioned. To open out the inward structure of the tangible incidents, we have portrayed the three-dimensional, contour plot, and two-dimensional graphs for different parametric values. The attained results demonstrate the EmSE technique for extracting soliton solutions to nonlinear evolution equations is efficient, compatible and reliable in nonlinear science and engineering.

关键词： (3+1)-dimensional ZK the extended QZK equation enhanced modified simple equation method soliton solutions NLEEs

Festosterone treatment and cardiovascular events in prescription database studies

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Asian Journal of Andrology 2018年第2期20卷 138-144页

作者： molly m Shores Department of Psychiatry and Behavioral Sciences University of Washington School of Medicine VA Puget Sound Health Care System 1660 South Columbian Way Seattle WA 98108 USA

Over the past decade, there has been a substantial increase in the number of men who are treated with testosterone. Despite this increase in the use of testosterone, the risks of adverse cardiovascular events are unclear as meta-analyses have reported conflicting findings and no clinical studies have been large enough or long enough to adequately assess for cardiovascular risks. The goal of this paper is to review large prescription database studies of testosterone treatment and adverse cardiovascular events and mortality with the aim of providing some guidance for clinicians and researchers in this controversial area.

关键词： cardiovascular diseases cohort studies myocardial infarction stroke testosterone/adverse effects thrombosis

Roles of secreted frizzled-related proteins in cancer

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Acta Pharmacologica Sinica 2007年第9期28卷 1499-1504页

作者： David m JABLONS Thoracic Oncology Laboratory Department of SurgeryComprehensive Cancer CenterUniversity of CaliforniaSan FranciscoCA 94115USASRI International333 Ravenswood AvenueMenlo ParkCA 94025 USA

The Wnt signaling pathway is implicated in a variety of biological processesranging from developmental cell fate to human *** components involvedin Wnt signaling have been under intense investigation over the last 2 *** canonical Wnt activation has been linked to tumor formation andinvolves activation of effector molecules or loss of tumor suppressor *** frizzled-related proteins (sFRPs) are Wnt *** recent years,accumulating evidence has suggested that sFRPs act as tumor suppressorsbecause their expression is frequently silenced in cancer by promoter ***,sFRPs may also promote cell growth in some ***,wefocus on the known knowledge of sFRPs in tumorigenesis.

关键词： Wnt signaling pathway secreted frizzledrelated proteins cancer

multiple scattering approach to X-ray absorption spectroscopy

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Nuclear Science and Techniques 2003年第1期14卷 9-19页

作者： m.BENFATTO INFN Laboratori Nazionali di Frascati 00044 Frascati Italy

In this paper we present the state of the art of the theoretical background needed for analyzing X-ray absorption spectra in the whole energy range. The multiple-scattering (mS) theory is presented in detail with some applications on real systems. We also describe recent progress in performing geometrical fitting of the XANES (X-ray absorption near-edge structure) energy region and beyond using a full multiple-scattering approach.

关键词： X-ray absorption spectroscopy X-ray absorption near-edge structure. multiple-scattering theory

Abundant different types of exact soliton solution to the (4+1)-dimensional Fokas and (2+1)-dimensional breaking soliton equations

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Communications in Theoretical Physics 2021年第10期73卷 64-80页

作者： Sachin Kumar monika Niwas m S Osman m A Abdou Department of mathematics Faculty of Mathematical SciencesUniversity of DelhiDelhi-110007India Department of mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt Department of mathematics Faculty of Applied ScienceUmm Alqura UniversityMakkah 21955Saudi Arabia Department of Physics College of SciencesUniversity of BishaP.O.Box 344Bisha 61922Saudi Arabia Department of Physics Faculty of ScienceMansoura University35516 MansouraEgypt

The prime objective of this paper is to explore the new exact soliton solutions to the higher-dimensional nonlinear Fokas equation and(2+1)-dimensional breaking soliton equations via a generalized exponential rational function(GERF) method. many different kinds of exact soliton solution are obtained, all of which are completely novel and have never been reported in the literature before. The dynamical behaviors of some obtained exact soliton solutions are also demonstrated by a choice of appropriate values of the free constants that aid in understanding the nonlinear complex phenomena of such equations. These exact soliton solutions are observed in the shapes of different dynamical structures of localized solitary wave solutions, singular-form solitons, single solitons,double solitons, triple solitons, bell-shaped solitons, combo singular solitons, breather-type solitons,elastic interactions between triple solitons and kink waves, and elastic interactions between diverse solitons and kink waves. Because of the reduction in symbolic computation work and the additional constructed closed-form solutions, it is observed that the suggested technique is effective, robust, and straightforward. moreover, several other types of higher-dimensional nonlinear evolution equation can be solved using the powerful GERF technique.

关键词： nonlinear evolution equations soliton solutions exact solutions generalized exponential rational function method solitary waves