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排序方式: 共有235条查询结果,搜索用时 46 毫秒
41.
Ehud Lehrer 《International Journal of Game Theory》1996,25(2):177-188
The notion of mediated talk in which players communicate through a mediator before starting the game is introduced. It is shown that a deterministic mechanized mediator receiving private inputs and producing public outputs can generate any rational correlated equilibrium with rational probabilities by a self-enforcing procedure. 相似文献
42.
We prove certain identities between Bessel functions attached to irreducible unitary representations ofPGL
2(R) and Bessel functions attached to irreducible unitary representations of the double cover ofSL
2(R). These identities give a correspondence between such representations which turns out to be the Waldspurger correspondence.
In the process we prove several regularity theorems for Bessel distributions which appear in the relative trace formula. In
the heart of the proof lies a classical result of Weber and Hardy on a Fourier transform of classical Bessel functions. This
paper constitutes the local (real) spectral theory of the relative trace formula for the Waldspurger correspondence for which
the global part was developed by Jacquet.
Research of first author was partially supported by NSF grant DMS-0070762.
Research of second author was partially supported by NSF grant DMS-9729992 and DMS 9971003. 相似文献
43.
Let k be a fixed integer and fk(n, p) denote the probability that the random graph G(n, p) is k‐colorable. We show that for k≥3, there exists dk(n) such that for any ϵ>0, (1) As a result we conclude that for sufficiently large n the chromatic number of G(n, d/n) is concentrated in one value for all but a small fraction of d>1. ©1999 John Wiley & Sons, Inc. Random Struct. Alg., 14, 63–70, 1999 相似文献
44.
45.
Selenoenzymes have a central role in maintaining cellular redox potential. These enzymes have selenenylsulfide bonds in their active sites that catalyze the reduction of peroxides, sulfoxides, and disulfides. The selenol/disufide exchange reaction is common to all of these enzymes, and the active site redox potential reflects the ratio between the forward and reverse rates of this reaction. The preparation of enzymes containing selenocysteine (Sec) is experimentally challenging. As a result, little is known about the kinetic role of selenols in enzyme active sites, and the redox potential of a selenenylsulfide or diselenide bond in a protein has not been experimentally determined. To fully evaluate the effects of Sec on oxidoreductase redox potential and kinetics, glutaredoxin 3 (Grx3) and all three Sec variants of its conserved (11)CXX(14)C active site were chemically synthesized. Grx3, Grx3(C11U), and Grx3(C14U) exhibited redox potentials of -194, -260, and -275 mV, respectively. The position of redox equilibrium between Grx3(C11U-C14U) (-309 mV) and thioredoxin (Trx) (-270 mV) suggests a possible role for diselenide bonds in biological systems. Kinetic analysis is consistent with the hypothesis that the lower redox potentials of the Sec variants result primarily from the greater nucleophilicity of the active site selenium rather than its role as either a leaving group or a "central atom" in the exchange reaction. The 10(2)-10(4)-fold increase in the rate of Trx reduction by the seleno-Grx3 analogues demonstrates that oxidoreductases containing either selenenyl-sulfide or diselenide bonds can have physiologically compatible redox potentials and enhanced reduction kinetics in comparison with their sulfide counterparts. 相似文献
46.
Multiphase thermoplastic hybrid for controlled release of antimicrobial essential oils in active packaging film 下载免费PDF全文
Itan Moshe Orli Weizman Michal Natan Gila Jacobi Ehud Banin Ana Dotan Amos Ophir 《先进技术聚合物》2016,27(11):1476-1483
Active packaging, a new technology concept in the field of food packaging, has been introduced in recent years in order to provide quality and safety, as well as extend the shelf life of food products. Antimicrobial (AM) agents can be incorporated directly into the active packaging and migrate in a controlled manner to the headspace between the food and the package, inhibiting bacteria growth on the food surface. Naturally derived AM agent, such as essential oils (EOs), has received considerable attention for food preservation purposes, because of their effective AM activity against various bacteria and fungi. In the present study, AM active film systems based on polypropylene/polyamide blends, montmorillonite nanoclays, and thymol EO were produced to investigate the feasibility of controlling the release rate of thymol from food packaging systems. Selective localization of thymol in a specific phase in the system that derives from thermodynamic affinity was assumed to be useful in controlling its migration rate from the film to the headspace. EO retention in the film under two different time conditions was measured by spectroscopic analysis. The release rate of EO was determined using Gas chromatography technique and analyzed by diffusion model approach. Inhibition of bacterial growth was periodically tested for Listeria and Escherichia coli bacteria. This study confirms the thermodynamic affinity of polyamide phase with thymol that has a positive effect in retaining the EO. Results show controlled AM behavior of the active packaging films, based on various blend compositions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
47.
We prove a generalization to the totally real field case of the Waldspurger’s formula relating the Fourier coefficient of
a half integral weight form and the central value of the L-function of an integral weight form. Our proof is based on a new interpretation of Waldspurger’s formula as a combination
of two ingredients – an equality between global distributions, and a dichotomy result for theta correspondence. As applications
we generalize the Kohnen–Zagier formula for holomorphic forms and prove the equivalence of the Ramanujan conjecture for half
integral weight forms and a case of the Lindel?f hypothesis for integral weight forms. We also study the Kohnen space in the
adelic setting.
The first author was partially supported by NSF grant DMS-0070762. The second author was partially supported by NSF grant
DMS-0355285.
Received: July 2005 Accepted: August 2005 相似文献
48.
The Mordell-Lang conjecture for function fields 总被引:1,自引:0,他引:1
Ehud Hrushovski 《Journal of the American Mathematical Society》1996,9(3):667-690
We give a proof of the geometric Mordell-Lang conjecture, in any characteristic. Our method involves a model-theoretic analysis of the kernel of Manin's homomorphism and of a certain analog in characteristic .
49.
Xiao-Juan Zhao Sara Lustigman Malcolm E. Kenney Ehud Ben-Hur 《Photochemistry and photobiology》1997,66(2):282-287
Syntheses for the new photosensitizers HOSiPc-OSi(CH3)2(CH2)3N(CH2)1 or 3(CH3)2, Pc 34 and Pc 25, have been developed and the order of activity of these photosensitizers and the previously reported photosensi-tizer Pc 4, HOSiPcOSi(CH3)2(CH2)3N(CH3)2, in the dark and with broad-band red light toward Plasmodium falciparum in red blood cell (RBC) suspensions has been studied. The order of activity has been found to be Pc 4 Pc 34 Pc 25. Thus, the activity of the photosensitizers under both sets of conditions is inversely proportional to the length of their terminal amino alkyl chains. The 50% inhibition dye concentration (IC50) in the dark for the parasites in RBC suspension with Pc 4 is 24 nM and the dye concentration and light fluence that yield:3 log10 of parasite inactivation with Pc 4 are 2 mM and 3 J/cm2, respectively. The synthesis of DNA and proteins by the parasites in culture was strongly inhibited by Pc 4 in the dark while parasite lactate dehydrogenase (pLDH) activity was unaffected. With Pc 4 and light, DNA and protein synthesis of the parasites in culture was strongly inhibited, pLDH activity of the parasites was moderately inhibited and ribosome density of the parasite cells was reduced. Gel electrophoresis studies showed that synthesis of all parasite proteins was inhibited to a similar extent. These results suggest that Pc 4 both in the dark and with light inactivates the cells by disturbing their machinery for the synthesis of not just one but a whole series of proteins. It is concluded that Pc 4 and light may be able to serve as a practical sterilization combination not only for HIV and other viruses but also for malaria parasites in RBC concentrates, and that Pc 4 by itself may have potential as a chemotherapeutic agent toward malaria. 相似文献
50.
Ehud Lehrer 《International Journal of Game Theory》1993,22(1):31-42
This note studies relations between limV n and the lower long-run average value ( \(\underline V \) ) in dynamic programming. It is shown that a certain bounded variation conditions of {V n } implies that limV n = \(\underline V \) . 相似文献