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Global Attractors and Determining Modes for the 3D Navier-Stokes-Voight Equations

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Chinese Annals of Mathematics,Series B 2009年第6期30卷 697-714页

作者： Varga K.KALANTAROV Edriss S.TITI Department of Mathematics Ko UniversityRumelifeneri YoluSariyer 34450IstanbulTurkey Department of Mathematics and Department of Mechanical and Aerospace Engineering University of California IrvineCalifornia 92697USA Department of Computer science and Applied Mathematics Weizmann Institute of ScienceRehovot 76100Israel

The authors investigate the long-term dynamics of the three-dimensional Navier- Stokes-Voight model of viscoelastic incompressible fluid. Specifically, upper bounds for the number of determining modes are derived for the 3D Navier-Stokes-Voight equations and for the dimension of a global attractor of a semigroup generated by these equations. Viewed from the numerical analysis point of view the authors consider the Navier-Stokes-Voight model as a non-viscous （inviscid） regularization of the three-dimensional Navier-Stokes equations. Furthermore, it is also shown that the weak solutions of the Navier-Stokes- Voight equations converge, in the appropriate norm, to the weak solutions of the inviscid simplified Bardina model, as the viscosity coefficient v →0.

关键词： Navier-Stokes-Voight Navier-Stokes-Voigt Global attractor Determining modes Regularization of the Navier-Stokes Turbulence models Viscoelastic models

Stabilization of Alliinase from Garlic by Osmolytes and the Mannose-Specific Lectin ASAI

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Journal of Pharmacy and Pharmacology 2018年第5期6卷 437-447页

作者： Irina Shin David Mirelman Lev Weiner Enrique Villar Valery L. Shnyrov Aharon Rabinkov Department of Life sciences Core Facilities Weizmann Institute of Science Rehovot 76100 Israel Department of Biomolecular science Weizmann Institute of Science Rehovot 76100 Israel Department of Chemical Research Support Weizmann Institute of Science Rehovot 76100 Israel Department of Biochemistry and Molecular Biology Universidad de Salamanca Salamanca 37007 Spain

Objectives： Alliinase is a pyridoxal-5＇-phosphate （PLP）-dependent enzyme responsible for the production of diallyl thiosulfinate （allicin）, the biologically active component of garlic, from alliin. The use of allicin for treatment of various diseases has been proposed but it is very unstable in the blood stream. This difficulty can be overcome by administration of alliin, together with a conjugate of alliinase directed towards the target cells. This, in turn requires a stable and active form of the enzyme. In this study we evaluate the stability of alliinase itself, in the presence mad absence of osmolytes, as well as that of its catalytically active complex with a mannose-specific lectin, ASAI （Allium sativum agglutinin I）, also presents in garlic. Methods： Alliinase, mad ASAI were both purified from garlic cloves. Thermal stability of alliinase itself, mad of its complexes with PLP and ASAI, in the presence mad absence of osmolytes, was analyzed by monitoring enzymic activity, and using DSC （differential scanning calorimetry）. Key findings： PLP exerts only a minor influence on alliinase structure and stablity. But both osmolytes and ASAI stabilize the enzyme considerably. Conclusions： The principle finding is that ASAI greatly stabilizes alliinase. Thus, the lectin-enzyme complex, which can be lyophilized and stored until used, provides an effective formulation of alliinase for generation of allicin from alliin in vivo.

关键词： Alliinase osmolyte mannose-specific lectin ASAI pyridoxal 5'-phosphate.

Variation of net primary productivity and its drivers in China’s forests during 2000-2018

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Forest Ecosystems 2020年第2期7卷 190-200页

作者： Yuhe Ji Guangsheng Zhou Tianxiang Luo Yakir Dan Li Zhou Xiaomin Lv State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological ScienceBeijing 100081China Key Laboratory of Alpine Ecology and Biodiversity Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Earth&Planetary sciences Weizmann Institute of Science76100 RehovotIsrael.

Background:Net primary productivity(NPP)in forests plays an important role in the global carbon ***,it is not well known about the increase rate of China’s forest NPP,and there are different opinions about the key factors controlling the variability of forest ***:This paper established a statistics-based multiple regression model to estimate forest NPP,using the observed NPP,meteorological and remote sensing data in five major forest *** fluctuation values of NPP and environment variables were extracted to identify the key variables influencing the variation of forest NPP by correlation ***:The long-term trends and annual fluctuations of forest NPP between 2000 and 2018 were *** results showed a significant increase in forest NPP for all five forest ecosystems,with an average rise of 5.2 gC·m-2·year-1 over *** 90%of the forest area had an increasing NPP range of 0-161 gC·m-2·*** NPP had an interannual fluctuation of 50-269 gC.m-2·year-1 for the five major forest *** evergreen broadleaf forest had the largest *** variability in forest NPP was caused mainly by variations in precipitation,then by temperature ***:All five forest ecosystems in China exhibited a significant increasing NPP along with annual fluctuations evidently during *** variations in China’s forest NPP were controlled mainly by changes in precipitation.

关键词： Net primary production(NPP) Forest ecosystem annual precipitation NPP model Fluctuation Variability

Decoherence Control of Single- and Multi-Partite Wavepackets

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Decoherence Control of Single- and Multi-Partite Wavepackets

p53 balances between tissue hierarchy and anarchy

第十二届全国量子光学学术会议

作者： Gershon Kurizki the weizmann institute of science rehovot 76100 Israel

＜正＞A comprehensive strategy, based on controlled time-dependent perturbations, is shown to effectively protect from decoherence either bound or continuous wavepackets, characterizing single- or entangled multi-partite systems. Applications to cold atoms, BEC, Josephson junctions and entangled pairs of guided photons are discussed.

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Journal of Molecular Cell Biology 2019年第7期11卷 553-563页

作者： Gabriela Koifman Ronit Aloni-Grinstein Varda Rotter Department of Molecular Cell Biology the Weizmann Institute of ScienceRehovot 7610001Israel Department of Biochemistry and Molecular Genetics Israel Institute for Biological ResearchNess ZionaIsrael

Normal tissues are organized in a hierarchical model,whereas at the apex of these hierarchies reside stem cells (SCs) capable of self-renewal and of producing differentiated cellular progenies,leading to normal development and ***,tumors are organized in a hierarchical manner,with cancer SCs residing at the apex,contributing to the development and nourishment of tumors .p53,the well-known 'guardian ofthe genome',possesses various roles in embryonic development as well as in adult SC life and serves as the ‘guardian of tissue hierarchy’.Moreover,p53 serves as a barrier for dedifferentiation and reprogramming by constraining the cells to a somatic state and preventing their conversion to *** the contrary,the mutant forms of p53 that lost theirtumor suppressor activity and gain oncogenic functions serve as 'inducers oftissue anarchy' and promote cancer *** this review,we discuss these two sides ofthe p53 token that sentence a tissue either to an ordered hierarchy and life or to anarchy and death.A better understanding of these processes may open new horizons for the development of new cancer therapies.

关键词： p53 stem cell gain of function cancer stem cells adult stem cells embryonic development tissue hierarchy

Bootstrap Algebraic Multigrid: Status Report, Open Problems, and Outlook

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Numerical Mathematics(Theory,Methods and Applications) 2015年第1期8卷 112-135页

作者： Achi Brandt James Brannick Karsten Kahl Ira Livshits Department of Applied Mathematics&Computer science The Weizmann Institute of Science76100 RehovotIsrael Department of Mathematics The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Mathematics University of WuppertalWuppertalGermany Department of Mathematical sciences Ball State UniversityMuncieIN 47306USA

This paper provides an overview of the main ideas driving the bootstrap algebraic multigrid methodology,including compatible relaxation and algebraic dis-tances for defining effective coarsening strategies,the least squares method for com-puting accurate prolongation operators and the bootstrap cycles for computing the test vectors that are used in the least squares *** review some recent re-search in the development,analysis and application of bootstrap algebraic multigrid and point to open problems in these *** from our previous research as well as some new results for some model diffusion problems with highly oscillatory diffusion coefficient are presented to illustrate the basic components of the BAMG algorithm.

关键词： Bootstrap algebraic multigrid compatible relaxation algebraic distance least squares interpolation

Blockage of IGF-1R signaling sensitizes urinary bladder cancer cells to mitomycin-mediated cytotoxicity

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Cell Research 2001年第2期11卷 107-115页

作者： SUN HONG ZHI, SHU FANG WU, ZENG HONG TU Department of Biological Regulation, weizmann institute of science, rehovot 76100, Istrel. Tel: 009728-9343182. E-mail: hongzhi@wicc.weizmann.ac.il Fax: 00972-8-9344116 State Key Laboratory of Drug Research, Shang Department of Biological Regulation Weizmann Institute of Science Rehovot Israel State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai China

A major problem which is poorly understood in the management of bladder cancer is low sensitivity to chemotherapy and high recurrence after transurethral resection. Insulin-like growth factor 1 receptor (IGF-1R) signaling plays a very important role in progression, invasion and metastasis of bladder cancer cells. In this study, we investigated whether IGF-1R was involved in the growth stimulating activity and drug resistance of bladder cancer cells. The results showed: The mRNAs of IGF-1, IGF-2 and IGF-1R were strongly expressed in serum-free cultured T24 cell line, whereas normal urothelial cells did not express these factors/receptors or only in trace leve1s; T24 cell responded far better to growth stimulation by IGF-1 than did normal urothelial cells; blockage of IGF1R by antisense oligodeoxynucleotide (ODN) significantly inhibited the growth of T24 cell and enhanced sensitivity and apoptosis of T24 cells to mitomycin (MMC). These results suggested that blockage of IGF-IR signaling might potentially contribute to the treatment of bladder cancer cells which are insensitive to chemotherapy.

关键词： IGF-1R signaling autocrine drug resistance apoptosis transitional cell carcinoma.

When should we give up on expectant management for patients with proximal ureteral stones?

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Exciton fine structure in twisted transition metal dichalcogenide heterostructures

当代泌尿学（英文） 2022年第1期16卷 9-14页

作者： Igal Shpunt Etay Elbaz Yuval Avda Jonathan Modai Dan Leibovici Brian Berkowitz Yaniv Shilo Department of Urology Kaplan Medical CenterRehovotIsrael Department of Earth and Planetary sciences Weizmann Institute of ScienceRehovotIsrael

Background:Proximal ureteral stones(PUS)have relatively low rates of spontaneous ***,some patients do on expectant *** aim was to compare risk factors for surgical intervention in patients with PUS who underwent primary intervention to those subjected to expectant management.Materials and methods:We retrospectively reviewed the medical charts of patients presented to the emergency room with symptoms of renal colic and underwent computerized tomography between August 2016 and August 2017.A total of 97 consecutive patients were identified with up to 10 mm *** collected patient demographics,clinical,and imaging data,and performed binary regression analysis for risk of intervention.Results:The average age was 49years(range 17-97)and average stone size was 7.1 mm(range 3-10).Forty-one patients underwent immediate intervention while the remaining 56 patients were treated *** the 56 patients treated conservatively,26 underwent delayed intervention while 30 reported spontaneous stone *** univariate analysis of all 97 patients,statistically significant risk factors for intervention were found based on stone size,age,serum lymphocyte,platelet counts,and stone *** these risk factors,stone size≥7mm(p=0.012,odds ratio=5.4)and platelet count?230K/mL(p=0.027,odds ratio=4.9)remained statistically significant on multivariate analysis.Conclusion:Stone size and platelet count were found to be risk factors for surgical intervention in patients with up to 10 mm *** findings may assist in identifying patients who are more suitable for conservative approach.

关键词： Nephrolithiasis Renal colic Ureteral calculi Ureterolithiasis Urolithiasis

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npj Computational Materials 2023年第1期9卷 417-423页

作者： Sudipta Kundu Tomer Amit H.R.Krishnamurthy Manish Jain Sivan Refaely-Abramson Centre for Condensed Matter Theory Department of PhysicsIndian Institute of ScienceBangalore 560012India Department of Molecular Chemistry and Materials science Weizmann Institute of ScienceRehovot 7610001Israel Present address:Department of Materials science and Engineering Stanford UniversityStanfordCA 94305USA

Moirésuperlattices of transition metal dichalcogenide(TMD)heterostructures give rise to rich excitonic phenomena associated with the interlayer twist *** calculations of excitons in such systems are typically based on model moirépotentials that mitigate the computational ***,predictive understanding of the electron-hole coupling dominating the excitations is crucial to realize the twist-induced modifications of the optical selection *** this work,we use many-body perturbation theory to evaluate the relation between twist angle and exciton properties in TMD *** present an approach for unfolding excitonic states from the moiréBrillouin zone onto the separate-layer *** this method to a large-angle twisted MoS^(2)/MoSe^(2) bilayer,we find that the optical spectrum is dominated by mixed electron–hole transitions with different momenta in the separate monolayers,leading to unexpected hybridization between interlayer and intralayer *** findings offer a design pathway for exciton layer-localization in TMD heterostructures.

关键词： twisted twist transition