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POLES OF ZETA FUNCTIONS OF COMPLETE INTERSECTIONS

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Chinese Annals of mathematics,Series B 2000年第2期21卷 187-200页

作者： WAN DAQING(department of mathematics, university of California, Irvine, CA 92697-3875, usa.) department of mathematics University of California Irvine CA 92697-3875 USA

A vanishing theorem is proved for e-adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite field of q elements, the reciprocal "poles" of the zeta function are always divisible by q as algebraic integers. A p-adic proof is also given, which leads to further q-divisibiliy of the poles or equivalently an improvement of the polar part of the AxKatz theorem for an affine complete intersection. Similar results hold for a projective complete intersection.

关键词： Pole Zeta function Complete intersection

The Green formula and heredity of algebras

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Science China mathematics 2005年第5期48卷 610-617页

作者： ZHANG Guanglian & WANG Shuai department of Mathematical Sciences, Tsinghua university, Beijing 100084, China Yancheng Teachers College, Yancheng 224002, China department of mathematics, johns hopkins university, baltimore, md2.2.8, U.S.A. 1. department of Mathematical Sciences Tsinghua University 100084 Beijing China 2. Yancheng Teachers College 224002 Yancheng China 3. department of mathematics Johns Hopkins University 21218 Baltimore MD USA

Let A be a finite dimensional algebra over a field k with q elements. It is shown that the Green formula is true in mod-A if and only if A is a hereditary algebra.

关键词： Green formula idempotent ideal hereditary algebra.

ECOLOGICAL CONSEQUENCES OFSOIL EROSION AND SEDIMENTATION

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International Journal of Sediment Research 1999年第2期14卷 355-361页

作者： Grace S. BRUSH (johns hopkins university , baltimore, Maryland, usa.

Sediment erosion and siltation in waterways can have ecological consequences as disastrous economically as those related to transport and flooding of adjacent lands. The impact of sediment erosion and deposition on human societies is recorded in many historical documents. The paleoecological record also provides evidence of the long-term effects of siltation. Sedimentation rates in the Chesapeake Bay estuary, in mid-Atlantic usa. have doubled and quadrupled over the last 200 to 300 years with the initiation and intensification of agriculture. The result has been filling in of many estuarine tributaries and the transformation of the estuary from a benthic to a planktonic ecosystem. This change took place as light became limiting in the water column and benthic plants could no longer photosynthesize, resulting in a proliferation of planktonic algae. Planktonic algal growth was also fueled by fertilizers attached to eroded soil particles. leading ultimately to eutrophication within the water column and anoxia of the bottom waters.

关键词： Sedimentation Civilizations Land use Sediment cores

FOUR STEP SCHEME FOR GENERAL MARKOVIAN FORWARD-BACKWARD SDES

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Journal of Systems Science & Complexity 2010年第3期23卷 546-571页

作者： Jin MA Jiongmin YONG Yanhong ZHAO department of mathematics University of Southern California Los Angeles CA 90089 USA department of mathematics University of Central Florida Orlando FL 32816 USA department of mathematics Purdue University West Lafayette IN 47907 USA

This paper studies a class of forward-backward stochastic differential equations (FBSDE)in a general Markovian *** forward SDE represents a large class of strong Markov semimartingales,and the backward generator requires only mild regularity *** authors showthat the Four Step Scheme introduced by Ma,et al.(1994) is still effective in this ***,the authors show that the adapted solution of the FBSDE exists and is unique over any prescribedtime duration;and the backward components can be determined explicitly by the forward componentvia the classical solution to a system of parabolic integro-partial differential *** importantconsequence the authors would like to draw from this fact is that,contrary to the general belief,in aMarkovian set-up the martingale representation theorem is no longer the reason for the well-posednessof the FBSDE,but rather a consequence of the existence of the solution of the decoupling integralpartialdifferential ***,the authors briefly discuss the possibility of reducing the regularityrequirements of the coefficients by using a scheme proposed by *** (2002) to the current case.

关键词： Forward-backward stochastic differential equations Four Step Scheme parabolic integropartial differential equation strong Markov semi-martingales.

Parameterization of the Non-Local Thermodynamic Equilibrium Source Function with Chemical Production by an Equivalent Two-Level Model

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Advances in Atmospheric Sciences 2003年第4期20卷 487-495页

作者： Xun ZHUThe johns hopkins university Applied Physics Laboratory, md 20723-6099, usa Applied Physics Laboratory The Johns Hopkins University 20723-6099 MD USA

The classic two-level or equivalent two-level model that includes only the statistical equilibrium of radiative and thermal processes of excitation and quenching between two vibrational energy levels is extended by adding chemical production to the rate equations. The modifications to the non-local thermodynamic equilibrium source function and cooling rate are parameterized by ϕc, which characterizes the ratio of chemical production to collisional quenching. For applications of broadband emission of O3 at 9.6 μm, the non-LTE effect of chemical production on the cooling rate and limb emission is proportional to the ratio of O to O3. For a typical [O]/[O3], the maximum enhancements of limb radiance and cooling rate are about 15%–30% and 0.03–0.05 K day−1, respectively, both occurring near the mesopause regions. This suggests that the broadband limb radiance above ∼80 km is sensitive to O3 density but not sensitive to the direct cooling rate along the line-of-sight, which makes O3 retrieval feasible but the direct cooling rate retrieval difficult by using the O3 9.6 μm band limb emission.

关键词： non-LTE radiative transfer ozone cooling ozone retrieval space weather

The link between intracellular calcium signaling and exosomal PD-L1 in cancer progression and immunotherapy

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Genes & Diseases 2024年第1期11卷 321-334页

作者： md Rakibul Alam md Mizanur Rahman Zhiguo Li department of Toxicology and Cancer Biology College of MedicineUniversity of KentuckyLexingtonKY 40506USA department of Medicine(Nephrology) Faculty of Medicine and DentistryUniversity of AlbertaEdmontonAlberta T6E2H7Canada

Exosomes are small membrane vesicles containing microRNA,RNA,DNA fragments,and proteins that are transferred from donor cells to recipient *** cells release exo-somes to reprogram the factors associated with the tumor microenvironment(TME)causing tu-mor metastasis and immune *** evidence revealed that cancer cell-derived exosomes carry immune inhibitory molecule program death ligand 1(PD-L1)that binds with re-ceptor program death protein 1(PD-1)and promote tumor progression by escaping immune ***,some FDA-approved monoclonal antibodies are clinicallyused for cancer treatment by blocking PD-1/PD-L1 *** notable treatment outcomes,some pa-tients show poor drug *** PD-L1 plays a vital role in lowering the treatment response,showing resistance to PD-1/PD-L1 blockage therapy through recapitulating the ef-fect of cell surface *** enhance therapeutic response,inhibition of exosomal PD-L1 is *** signaling is the central regulator of tumorigenesis and can regulate exosome biogenesis and secretion by modulating Rab GTPase family and membrane fusion ***-mune checkpoints are also connected with calcium signaling and calcium channel blockers like amlodipine,nifedipine,lercanidipine,diltiazem,and verapamil were also reported to suppress cellular PD-L1 ***,to enhance the PD-1/PD-L1 blockage therapy response,the reduction of exosomal PD-L1 secretion from cancer cells is in our therapeutic *** this review,we proposed a therapeutic strategy by targeting calcium signaling to inhibit the expression of PD-L1-containing exosome levels that could reduce the anti-PD-1/PD-L1 therapy resistance and increase the patient's drug response rate.

关键词： Calcium signaling CD8^(+)T cells Exosomal PD-L1 Exosomes biogenesis Immunosuppression Immunotherapy

CONVERGENCE OF CASCADE ALGORITHMS AND SMOOTHNESS OF REFINABLE DISTRIBUTIONS

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Chinese Annals of mathematics,Series B 2003年第3期24卷 367-386页

作者： SUN QIYU department of mathematics, university of Houston, Houston, TX 77204, usa. department of mathematics, National university of Singapore, 10 Kent Ridge Crescent, 119260, Singapore. Univ Houston Dept Math Houston TX 77204 USA Natl Univ Singapore Dept Math Singapore 119260 Singapore

In this paper, the author at first develops a method to study convergence of the cascadealgorithm in a Banach space without stable assumption on the initial (see Theorem 2.1), andthen applies the previous result on the convergence to characterizing compactly supportedrefinable distributions in fractional Sobolev spaces and Holder continuous spaces (see Theorems3.1, 3.3, and 3.4). Finally the author applies the above characterization to choosing appropriateinitial to guarantee the convergence of the cascade algorithm (see Theorem 4.2).

关键词： Cascade algorithm Cascade operator Refinable distribution Shift-invariant space Linear independent shifts Stable shifts Fractional Sobolev space

DESIGN AND ANALYSIS OF HIGH-THROUGHPUT SCREENING EXPERIMENTS

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Journal of Systems Science & Complexity 2011年第4期24卷 711-724页

作者： Xianggui QU department of mathematics and Statistics Oakland University Rochester MI 48309 USA.

Saturated row-column designs are studied to eliminate positional effects in primary high- throughput screening experiments. Compared to designs currently used in practice, all compounds in the designs considered are comparable within each microplate in spite of the existence of row and column effects. The designs considered in this paper also have the maximum number of compounds arranged in each microplate. Two statistical methods are used to choose leading compounds in the designs considered. These two methods take full advantages of effect sparsity in primary screening. Simulation studies are carried out to compare the two statistical methods with two ad hoc methods in selecting active compounds. A method that maintains balanced false positives and false negatives is recommended.

关键词： Bscore high-throughput screening row-column design saturated design Zscore.

Boundary Layer Theory and the Zero-Viscosity Limit of the Navier-Stokes Equation

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Acta Mathematica Sinica,English Series 2000年第2期16卷 207-218页

作者： Weinan E department of mathematics and Program in Applied and Computational mathematics,Princeton university,usa department of mathematics and Program in Applied and Computational mathematics Princeton University Princeton USA

A central problem in the mathematical analysis of fluid dynamics is the asymptotic limit of the fluid flow as viscosity goes to *** is particularly important when boundaries are present since vorticitv is typically generated at the boundary as a result of boundary layer *** boundary laver theory,developed by Prandtl about a hundred years ago,has become a standard tool in addressing these *** at the mathematical level,there is still a lack of fundamental understanding of these questions and the validity of the boundary layer *** this article,we review recent progresses on the analysis of Prandtl’s equation and the related issue of the zero-viscosity limit for the solutions of the Navier-Stokes *** also discuss some directions where progress is expected in the near future.

关键词： Boundary layer Blow-up Zero-viscosity limit Prandtl’s equation