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Nobody doubts that the discovery of hadrons with charm of the hidden and open variety – i.e. charmonium as well as D mesons – was instrumental in the acceptance of the Standard Model (SM) in general, and of quarks as physical degrees of freedom, rather than objects of mere mathematical convenience, in particular. Yet charm is all too often viewed as a quantum number with a great past and with no particularly interesting future. This is due to SM predictions of a rather dull electroweak phenomenology of CKM parameters, a low frequency for $D^0 - \bar D^0 $ oscillations, tiny (at best) CP asymmetries, and extremely rare flavor changing neutral currents which, in any case, are swamped by huge backgrounds from long-distance dynamics... [ABSTRACT FROM AUTHOR]

A new type of cavitation damage has been observed on the turbines installed at the Three Gorges Power Station despite no cavitation detected during model tests. Metallurgical and fluid dynamic analysis suggests that this cavitation is triggered by boundary-layer turbulent production; the damaged (roughened) spot in turn triggers subsequent cavitation (damage) immediately down stream. This forms a sustainable dynamic process, resulting in long and equal-width streamwise damage-strips with spanwise regularity reflecting the spanwise stochastic characteristics of turbulent production. Owing to the heat effect of cavitation, intergranular corrosion takes place through sensitization process, leaving the damaged surface with a corrosion appearance. Also, bluing presents at the damaged tails, owing to the nature of low-intensity damage. Extremely large turbines are much more susceptible to this type of cavitation (damage) owing to the similarity laws currently employed for turbine development not concerning the freestream turbulence and the boundary-layer dynamics. [ABSTRACT FROM AUTHOR]

We present the effective chiral Lagrangian of mesons (peusodoscalars, vectors and axial-vectors) obtained in the chiral limit by using two approaches. The first approach is based on symmetries: the explicit global chiral symmetry and hidden local chiral symmetry. In this approach, it is noticed that there are in general fourteen interacting terms up to the dimension-four of covariant derivative for meson fields rather than the usual eleven interacting terms given in literature from hidden local symmetry approach. Of particular, the additional terms are found to be very important for understanding the vector meson dominance and providing consistent predictions on the decay rates of a1 → γπ and a1 → ρπ as well as for resulting a consistent effective chiral Lagrangian with chiral perturbation theory. The second approach is motivated from the chiral symmetry of chiral quarks and the bound state solutions of nonperturbative QCD at low energy and large Nc. The second approach is more fundamental in the sense that it is based on the QCD Lagrangian of quarks and only relies on two basic parameters in addition to the ones in the standard model. As a consequence, it allows us to extract, in terms of only two basic parameters, all the fourteen parameters in the more general effective Lagrangian constructed from symmetries in the first approach. It is surprising to note that except the necessity of three additional new interacting terms introduced in this paper, the resulting values of the coupling constants for other three interacting terms at the dimension-four are also quite different from the ones given in the literature. It is likely that the structures of the effective chiral Lagrangian for the dimension-four given in the literatures by using hidden local symmetry are incomplete and consequently the resulting coulpings are not reliable. It is shown that the more general effective chiral Lagrangian given in the present paper shall provide a more consistent prediction for all the low energy phenomenology of ρ - a1 system and result in a more consistent description on the low energy behavior of light flavor mesons. Its fourteen parameters up to the dimension-four of covariant derivative may be uniquely determined from the effective chiral theory based on the second approach, which is consistent with the chiral perturbation theory. [ABSTRACT FROM AUTHOR]

A systematic calculation for the transition form factors of heavy to light mesons (B, Bs, D, Ds → π, K, η, ρ, K*, ω, ϕ) is carried out by using light-cone sum rules in the framework of heavy quark effective field theory. The heavy quark symmetry at the leading order of 1/mQ expansion enables us to reduce the independent wave functions and establish interesting relations among form factors. Some relations hold for the whole region of momentum transfer. The meson distribution amplitudes up to twist-4 including the contributions from higher conformal spin partial waves and light meson mass corrections are considered. The CKM matrix elements |Vub|, |Vcs| and |Vcd| are extracted from some relatively well-measured decay channels. A detailed prediction for the branching ratios of heavy to light meson decays is then presented. The resulting predictions for the semileptonic and radiative decay rates of heavy to light mesons (B, Bs, D, Ds → π, K, η, ρ, K*, ω, ϕ) are found to be compatible with the current experimental data and can be tested by more precise experiments at B-factory, LHCb, BEPCII and CLEOc. [ABSTRACT FROM AUTHOR]

The physical origin of severe low-frequency pressure fluctuation frequently observed in Francis hydraulic turbines under off-design conditions, which greatly damages the structural stability of turbines and even power stations, is analyzed based on the hydrodynamic stability theory and our Reynolds-averaged Navier-Stokes equation simulation (RANS) of the flow in the entire passage of a Francis turbine. We find that spontaneous unsteady vortex ropes, which induce severe pressure fluctuations, are formed due to the absolute instability of the swirling flow at the conical inlet of the turbine's draft tube. [ABSTRACT FROM AUTHOR]

The lifetime differences of bottom hadrons are known to be properly explained within the framework of heavy quark effective field theory (HQEFT) of QCD via the inverse expansion of the dressed heavy quark mass. In general, the spectrum around the endpoint region is not well behaved due to the invalidity of 1/mQ expansion near the endpoint. The curve fitting method is adopted to treat the endpoint behavior. It turns out that the endpoint effects are truly small and the explanation on the lifetime differences in the HQEFT of QCD is then well justified. The inclusion of the endpoint effects makes the prediction on the lifetime differences and the extraction on the CKM matrix element |Vcb| more reliable. [ABSTRACT FROM AUTHOR]

The heavy quark effective field theory (HQEFT) is revisited in a more intuitive way. It is shown that HQEFT is a consistent large component QCD of heavy quarks. In the nonrelativistic limit, HQEFT recovers the nonrelativistic QCD (NRQCD). The resulting new effects in the HQEFT of QCD are carefully re-examined. It is then natural to give comments on the usual heavy quark effective theory (HQET). Consistent phenomenological applications of HQEFT exhibit its interesting features and completeness in comparison with HQET. It then becomes manifest why we shall base on the HQEFT of QCD rather than HQET which is incomplete for computing 1/m[sub Q] corrections. More precise extraction for ∣V[sub cb]∣ and ∣V[sub ub]∣ in the HQEFT of QCD is emphasized. [ABSTRACT FROM AUTHOR]

B meson rare decays (B → K(K*)l&lsline; and B → K*γ) are analyzed in the framework of effective field theory of heavy quarks. The semileptonic and penguin type form factors for these decays are calculated by using the light cone sum rules method at the leading order of 1/m[SUBQ] expansion. Four exact relations between the two types of form factors are obtained at the leading order of 1/m[SUBQ] expansion. In particular, the relations are found to hold for the whole momentum transfer region. We also investigate the validity of the relations resulting from the large energy effective theory based on the general relations obtained in the present approach. The branching ratios of the rare decays are presented and their potential importance for extracting the CKM matrix elements and probing new physics is emphasized. [ABSTRACT FROM AUTHOR]

Repeat breeders cause great economic loss in dairy herds. This study determined the efficacy of simple aquapuncture therapy (acupuncture combined with injection) to treat repeat breeders in two dairy herds (one in Hsinchu County and the other in Tainan County). Both herds had used gonadotropin-releasing hormone (GnRH) beforehand to treat the symptom but the success rate was poor — about 30%. Therefore, cows that failed to respond to GnRH were given the aquapuncture treatment. A total of 18 animals (two heifers and 16 cows) that had failed to conceive to 3-9 services were treated by aquapuncture, in which 10 ml and 5 ml of 50% glucose solution were injected at Baihui (Hundred Meetings, the depression in the center of the lumbosacral space) and Shenpeng (Kidney Shelf, the depression in the space between the lumbar vertebral transverse processes 5-6) acupoints, respectively with a 21G, 1.5-inch hypodermic needle. Both acupoints belong to the traditional acupuncture points of bovine and equine systems. Most animals showed heat within 14 days after aquapuncture and were inseminated artificially. Serum progesterone concentrations and rectal palpation were used for pregnancy diagnosis. The pregnancy rate after the treatment was 14/18 (77.7%) and 12/18 (66.6%) based on progesterone concentration and rectal palpation respectively, suggesting acupuncture as a simple and effective method to treat repeat breeders in dairy herds. However, the final result obtained from actual delivery of fetus in the experimental animals was only 8/18 (44.4%). [ABSTRACT FROM AUTHOR]

Exclusive semileptonic B decays into excited charmed mesons (D[sub 1], D[sup *, sub 2]) are studied up to the order of 1/m[sub Q] in the framework of the heavy quark effective field theory (HQEFT), which contains the contributions of both particles and antiparticles. Two wave functions η[sup b, sub 0] and η[sup c, sub 0], which characterize the contributions from the kinematic operator at the order of 1/m[sub Q], are calculated by using QCD sum rule approach in HQEFT. Zero recoil values of other two wave functions κ'[sub 1] and κ'[sub 2] are extracted from the excited charmed-meson masses. Possible effects from the transition wave functions arising from the chromomagnetic operators at the order of 1/m[sub Q] are analyzed. It is shown that the experimental measurements for the branching ratios of B → D[sub 1]lv and B → D[sup *, sub 2]lv can be understood in the framework of HQEFT. [ABSTRACT FROM AUTHOR]

Within the complete heavy quark effective field theory (HQEFT), the QCD sum rule approach is used to evaluate the decay constants including 1/m[sub Q] corrections and the Isgur-Wise function and other additional important wave functions concerned at 1/m[sub Q] for the heavy-light mesons. The number of unknown wave functions or form factors in HQEFT is shown to be much less than the one in the usual heavy quark effective theory (HQET). The values of wave functions at zero recoil are found to be consistent with the ones extracted from the interesting relations (which are resulted from the HQEFT) between the hadron masses and wave functions at zero recoil. The results for the decay constants are consistent with the ones from full QCD sum rule and Lattice calculations. The 1/m[sub Q] corrections to the scaling law f[sub M] ∼ F/√m[sub M] are found to be small in HQEFT, which demonstrates again the validity of 1/m[sub Q] expansion in HQEFT. It is also shown that the residual momentum υ · κ of heavy quark within heavy-light hadrons is indeed around the binding energy &Λmacr; of the heavy hadrons, which turns out to be in agreement with the expected one in the HQEFT. Therefore such a calculation provides a consistent check on the HQEFT and shows that the HQEFT is more reliable than the usual HQET for describing a slightly off-mass shell heavy quark within hadron as the usual HQET seems to lead to large 1/m[sub Q] corrections in evaluating the meson decay constants. It is emphasized that the introduction of the "dressed heavy quark" mass is useful for the heavy-light mesons (Qq) with m[sub Q] » &Λmacr; » m[sub q], while for heavy-heavy bound states (ψ[sub 1]ψ[sub 2]) with masses m[sub 1], m[sub 2] » &Λmacr;, like bottom-charm hadrons or similarly for muonium in QED, one needs to treat both particles as heavy effective particles via 1/m[sub 1] and 1/m[sub 2] expansions and redefine the... [ABSTRACT FROM AUTHOR]

Inclusive bottom hadron decays are analyzed based on the heavy quark effective field theory (HQEFT). Special attentions in this paper are paid to the b → u transitions and nonspectator effects. As a consequence, the CKM quark mixing matrix elements |V[sub ub]| and |V[sub cb]| are reliably extracted from the inclusive semileptonic decays B → X[sub υ]eν and B → X[sub c]eν. Various observables, such as the semileptonic branch ratio B[sub SL], the lifetime differences among B[sup -], B[sup 0], B[sub s] and Λ[sub b] hadrons, the charm counting n[sub c], are predicted and found to be consistent with the present experimental data. [ABSTRACT FROM AUTHOR]

We apply the new formulation of heavy quark effective field theory (HQEFT) to the inclusive decays of bottom hadrons. The long-term ambiguity of using heavy quark mass or heavy hadron mass for inclusive decays is clarified within the framework of the new formulation of HQEFT. The 1/m[sub b] order corrections are absent and contributions from 1/m²[sub b] terms are calculated in detail. This enables us to reliably extract the important CKM matrix element V[sub cb] from the inclusive semileptonic decay rates. The resulting lifetime ratios τ(B[sup 0, s ub s])/τ(B[sup 0]) and τ(λ[sub b])/τ(B[sup 0]) are found to well agree with the experimental data. We also calculate in detail the inclusive semileptonic branching ratios and the ratios of the τ and β decay rates as well as the charm countings in the B[sup 0], B[sup 0, sub s] and λ[sub b] systems. For B[sup 0] decays, all the observables are found to be consistent with the experimental data. More precise data for the B[sup 0] decays and further experimental measurements for the B[sup 0, sub s] and λ[sub b] systems will be very useful for testing the framework of new formulation of HQEFT at the level of higher order corrections. [ABSTRACT FROM AUTHOR]

The heavy quark effective field theory (HQEFT) containing both effective "quark fields" and "antiquark fields" is investigated in detail. By integrating out (but not neglecting) the effective antiquark fields, we present a new formulation of effective theory which differs from the usual heavy quark effective theory (HQET) and exhibits valuable features because of the inclusion of the contributions from the antiquark fields. Matrix elements of vector and axial vector heavy quark currents between pseudoscalar and vector mesons containing a heavy quark (b or c) are then evaluated systematically up to the order of 1/m²[sub Q] and parametrized by a set of universal form factors. With a consistent normalization condition between the effective heavy hadron states, the form factors at zero recoil are related to the ground state meson masses, which enables us to estimate the values of form factors at zero recoil. In particular, Luke's theorem comes out automatically in the new formulation of HQEFT without the need of imposing the equation of motion iv · DQ[sup +, sub v] = 0. Consequently, the differential decay rates of both B → D*lv and B → Dlv do not receive 1/m[sub Q] order corrections at zero recoil, which is not the case in the usual HQET. Thus we quote that the Cabibbo-Kobayashi-Maskawa matrix element V[sub cb] can nicely be extracted from either of these two exclusive semileptonic decays at the order of 1/m²[sub Q]. Our estimates for V[sib cb] are presented. [ABSTRACT FROM AUTHOR]

New physics effects on the B[sup 0]–[formula] mixing and B-decay amplitudes are discussed. By a combined analysis, the models of new physics can be partially distinguished. It is emphasized that the extraction of unitarity angles β and γ through rare decay [formula] and charged B decay B[sup ±]→DK[sup ±] respectively is not likely to be affected by new physics. Such an observation could be used to distinguish the new physics effects from different models. For instance, the top quark two-Higgs doublet model can be easily separated from those models without new phase in B-decay amplitudes, and can be further distinguished from the most general two-Higgs doublet model by its absence of new phase in the B[sup 0]–[formula] mixing. [formula available in full text]. [ABSTRACT FROM AUTHOR]