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Estimating epsilon'/epsilon. A Review  [PDF]
S. Bertolini,J. O. Eeg,M. Fabbrichesi
Physics , 1998, DOI: 10.1103/RevModPhys.72.65
Abstract: The real part of epsilon'/epsilon measures direct CP violation in the decays of the neutral kaons in two pions. It is a fundamental quantity which has justly attracted a great deal of theoretical as well as experimental work. Its determination may answer the question of whether CP violation is present only in the mass matrix of neutral kaons (the superweak scenario) or also at work directly in the decays. After a brief historical summary, we discuss the present and expected experimental sensitivities. In the light of these, we come to the problem of estimating epsilon'/epsilon in the standard model. We review the present (circa 1998) status of the theoretical predictions of epsilon'/epsilon. The short-distance part of the computation is now known to the next-to-leading order in QCD and QED and therefore well under control. On the other hand, the evaluation of the hadronic matrix element of the relevant operators is where most of the theoretical uncertainty still resides. We analyze the results of the currently most developed calculations. The values of the B_i parameters in the various approaches are discussed, together with the allowed range of the relevant combination of the Cabibbo-Kobayashi-Maskawa entries Im V_{td}V^*_{ts}. We conclude by summarizing and comparing all up-to-date predictions of epsilon'/epsilon. Because of the intrinsic uncertainties of the long-distance computations, values ranging from 10^{-4} to a few times 10^{-3} can be accounted for in the standard model. Since this range covers most of the present experimental uncertainty, it is unlikely that new physics effects can be disentangled from the standard model prediction. For updates on the review and additional material see http://www.he.sissa.it/review/.
Theoretical status of epsilon'/epsilon  [PDF]
M. Ciuchini,G. Martinelli
Physics , 2000, DOI: 10.1016/S0920-5632(01)01359-7
Abstract: We review the theory of epsilon'/epsilon and present an updated phenomenological analysis using hadronic matrix elements from lattice QCD. The present status of the computation of epsilon'/epsilon, considering various approaches to the matrix-element evaluation, is critically discussed.
Theoretical Status of epsilon'/epsilon  [PDF]
Andrzej J. Buras
Physics , 1999,
Abstract: We review the present theoretical status of the CP violating ratio epsilon'/epsilon in the Standard Model (SM) and confront its estimates with the most recent data. In particular we review the present status of the most important parameters m_s, B_6^(1/2), B_8^(3/2), \Lambda_MSbar and Omega_{\eta+\eta'}. While the sign and the order of magnitude of SM estimates for epsilon'/epsilon agree with the data, for central values of these parameters most estimates of epsilon'/epsilon in the SM are substantially below the grand experimental average (21.2\pm 4.6)\cdot 10^{-4}. Only in a small corner of the parameter space can epsilon'/epsilon in SM be made consistent with experimental results. In view of very large theoretical uncertainties, it is impossible to conclude at present that the data on epsilon'/epsilon indicate new physics. A brief discussion of epsilon'/epsilon beyond the Standard Model is presented.
Calculation of epsilon'/epsilon  [PDF]
Stefano Bertolini
Physics , 2002, DOI: 10.1063/1.1478825
Abstract: I shortly review the present status of the theoretical calculations of epsilon'/epsilon and the comparison with the present experimental results. I discuss the role of higher order chiral corrections and in general of non-factorizable contributions for the explanation of the Delta I = 1/2 selection rule and direct CP violation in kaon decays. Still lacking reliable lattice calculations, analytic methods and phenomenological approaches are helpful in understanding correlations among theoretical effects and the experimental data. Substantial progress from lattice QCD is expected in the coming years.
Theoretical status of epsilon'/epsilon  [PDF]
A. Pich
Physics , 2000, DOI: 10.1016/S0920-5632(00)01113-0
Abstract: The Standard Model prediction for epsilon'/epsilon is updated, taking into account the most recent theoretical developments. The final numerical value, epsilon'/\epsilon = (17\pm 6) x 10^{-4}, is in good agreement with present measurements.
Supersymmetry predictions for epsilon'/epsilon  [PDF]
S. Khalil
Physics , 2000,
Abstract: We study the predictions for the direct CP violation parameter epsilon'/epsilon in a class of string-inspired model with non-universal soft A-terms. We show that the non-universality of the A-terms plays an important rule in enhancing the supersymmetric contributions to the CP violation epsilon'/epsilon. In particular, the supersymmetric contribution to epsilon'/epsilon can be of order the KTeV result, epsilon'/epsilon ~ 10^(-3).
Progress in biosynthesis of epsilon-poly-L-lysine and genetic transformation for epsilon-poly-L-lysine producer--a review

Qingping Wu,Shengrong Liu,Jumei Zhang,

微生物学报 , 2011,
Abstract: Epsilon-Poly-L-lysine (epsilon-PL) is a polymer with strong antimicrobial activity and consists of 25-35 L-lysine monomers linked via epsilon-amino-alpha-carboxyl peptide bond. This polymer is one of only two homo-poly (amino acid) polymers known in nature. To date, the biosynthesis mechanism of epsilon-PL was remained unclear. Recently, epsilon-PL synthetase was identified as a nonribosomal peptide synthetase and it utilized L-lysine to synthesize epsilon-PLs of various chain length by iteratively condensing reaction, which was similar to type I polyketide synthase and was not determined by epsilon-PL-degrading enzyme. Meanwhile, the shutter vectors pLAE001 and pLAE003, special for epsilon-PL producer have been constructed, which is significant for studying epsilon-PL biosynthesis. In this review, the biosynthesis of epsilon-PL and the genetic transformation were introduced. Also, the study in our group was presented and the views related to e-PL study were raised. Finally, the prospect of application of combinational biosynthesis in epsilon-PL-producing strain improvement was also discussed considering epsilon-PL synthetase is a nonribosomal peptide synthetase containing several modules.
Sources of alpha-, beta-, gamma-, delta- and epsilon-carotenes: a twentieth century review
Barbosa-Filho, José M.;Alencar, Adriana A.;Nunes, Xirley P.;Tomaz, Anna C. de Andrade;Sena-Filho, José G.;Athayde-Filho, Petr?nio F.;Silva, Marcelo S.;Souza, Maria F. Vanderlei de;da-Cunha, Emidio V. Leit?o;
Revista Brasileira de Farmacognosia , 2008, DOI: 10.1590/S0102-695X2008000100023
Abstract: since humans cannot synthesize carotenoids, they depend upon the diet exclusively for the source of these micronutrients. it has claimed that they may alleviate chronic diseases such as cancers. the present communication constitutes a global review of the scientific literature on plants and others organisms that biosynthesize carotenoids, which include the series alpha-, beta-, gamma-, delta- and epsilon-carotenes. the results of the literature survey lists more than five hundred sources.
Theoretical status of epsilon'/epsilon  [PDF]
Matthias Jamin
Physics , 1999,
Abstract: The present theoretical status of the parameter for direct CP violation epsilon'/epsilon in the Standard Model is reviewed and compared with most recent experimental measurements of the same quantity. After collecting the basic expressions for epsilon'/epsilon, the situation of hadronic matrix element calculations is summarised. The matrix elements constitute the dominant source of uncertainty for theoretical determinations of epsilon'/epsilon. For central values of the input parameters, the numerical analysis then yields results which are generally below the experimental data. Possible reasons for these findings are discussed.
Dissipative contributions to epsilon'/epsilon  [PDF]
F. Benatti,R. Floreanini
Physics , 1999, DOI: 10.1142/S0217732399001619
Abstract: The time evolution and decay of the neutral kaon system can be described using quantum dynamical semigroups. Non-standard terms appear in the expression of relevant observables; they can be parametrized in terms of six, new phenomenological constants. We discuss how the presence of these constants affects the determination of the parameter epsilon'/epsilon.
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