Flavor constraints on two-Higgs-doublet models with general diagonal Yukawa couplings

We consider constraints from flavor physics on two-Higgs-doublet models (2HDM) with general, flavor-diagonal, Yukawa couplings. Analyzing the charged Higgs contribution to different observables, we find that $b\to s\gamma$ transitions and $\Delta M_{B_d}$ restrict the coupling $\lambda_{tt}$ of the top quark (corresponding to $\cot\beta$ in models with a $Z_2$ symmetry) to $|\lambda_{tt}|<1$ for $m_{H^+}\lesssim 500$ GeV. Stringent constraints from $B$ meson decays are obtained also on the other third generation couplings $\lambda_{bb}$ and $\lambda_{\tau\tau}$, but with stronger dependence on $m_{H^+}$. For the second generation, we obtain constraints on combinations of $\lambda_{ss}$, $\lambda_{cc}$, and $\lambda_{\mu\mu}$ from leptonic $K$ and $D_s$ decays. The limits on the general couplings are translated to the common 2HDM types I -- IV with a $Z_2$ symmetry, and presented on the $(m_{H^+},\tan\beta)$ plane. The flavor constraints are most excluding in the type II model which lacks a decoupling limit in $\tan\beta$. We obtain a lower limit $m_{H^+}\gtrsim 300$ GeV in models of type II and III, while no lower bound on $m_{H^+}$ is found for types I and IV.Comment: 24 pages, 11 figures. v2: Minor changes to text and numerics, results and conclusions unchanged. References adde

Exploring CP Violation in the MSSM

We explore the prospects for observing CP violation in the minimal supersymmetric extension of the Standard Model (MSSM) with six CP-violating parameters, three gaugino mass phases and three phases in trilinear soft supersymmetry-breaking parameters, using the CPsuperH code combined with a geometric approach to maximize CP-violating observables subject to the experimental upper bounds on electric dipole moments. We also implement CP-conserving constraints from Higgs physics, flavour physics and the upper limits on the cosmological dark matter density and spin-independent scattering. We study possible values of observables within the constrained MSSM (CMSSM), the non-universal Higgs model (NUHM), the CPX scenario and a variant of the phenomenological MSSM (pMSSM). We find values of the CP-violating asymmetry A_CP in b -> s gamma decay that may be as large as 3%, so future measurements of A_CP may provide independent information about CP violation in the MSSM. We find that CP-violating MSSM contributions to the B_s meson mass mixing term Delta M_Bs are in general below the present upper limit, which is dominated by theoretical uncertainties. If these could be reduced, Delta M_Bs could also provide an interesting and complementary constraint on the six CP-violating MSSM phases, enabling them all to be determined experimentally, in principle. We also find that CP violation in the h_{2,3} tau+ tau- and h_{2,3} tbar t couplings can be quite large, and so may offer interesting prospects for future pp, e+ e-, mu+ mu- and gamma gamma colliders.Comment: 36 pages, 32 figure

B -> K* mu+ mu- optimised observables in the MSSM

We provide a detailed analysis of the impact of the newly measured optimised observables in the B -> K* mu+ mu- decay by the LHCb experiment. The analysis is performed in the MSSM, both in the context of the usual constrained scenarios, and in the context of a more general set-up where the SUSY partner masses are independent. We show that the global agreement of the MSSM solutions with the data is still very good. Nevertheless, especially in the constrained scenarios, the limits from B -> K* mu+ mu- are now very strong, and are at the same level as the well-known b -> s gamma constraints. We describe the implications of the B -> K* mu+ mu- measurements both on the Wilson coefficients and on the SUSY parameters.Comment: 20 pages, 6 figure

Dynamic mean-field and cavity methods for diluted Ising systems

We compare dynamic mean-field and dynamic cavity as methods to describe the stationary states of dilute kinetic Ising models. We compute dynamic mean-field theory by expanding in interaction strength to third order, and compare to the exact dynamic mean-field theory for fully asymmetric networks. We show that in diluted networks the dynamic cavity method generally predicts magnetizations of individual spins better than both first order ("naive") and second order ("TAP") dynamic mean field theory

Crucial Ignored Parameters on Nanotoxicology: The Importance of Toxicity Assay Modifications and “Cell Vision”

Until now, the results of nanotoxicology research have shown that the interactions between nanoparticles (NPs) and cells are remarkably complex. In order to get a deep understanding of the NP-cell interactions, scientists have focused on the physicochemical effects. However, there are still considerable debates about the regulation of nanomaterials and the reported results are usually in contradictions. Here, we are going to introduce the potential key reasons for these conflicts. In this case, modification of conventional in vitro toxicity assays, is one of the crucial ignored matter in nanotoxicological sciences. More specifically, the conventional methods neglect important factors such as the sedimentation of NPs and absorption of proteins and other essential biomolecules onto the surface of NPs. Another ignored matter in nanotoxicological sciences is the effect of cell “vision” (i.e., cell type). In order to show the effects of these ignored subjects, we probed the effect of superparamagnetic iron oxide NPs (SPIONs), with various surface chemistries, on various cell lines. We found thatthe modification of conventional toxicity assays and the consideration of the “cell vision” concept are crucial matters to obtain reliable, and reproducible nanotoxicology data. These new concepts offer a suitable way to obtain a deep understanding on the cell-NP interactions. In addition, by consideration of these ignored factors, the conflict of future toxicological reports would be significantly decreased

A compact representation of the 2 photon 3 gluon amplitude

A compact representation of the loop amplitude gamma gamma ggg -> 0 is presented. The result has been obtained by using helicity methods and sorting with respect to an irreducible function basis. We show how to convert spinor representations into a field strength representation of the amplitude. The amplitude defines a background contribution for Higgs boson searches at the LHC in the channel H -> gamma gamma + jet which was earlier extracted indirectly from the one-loop representation of the 5-gluon amplitude.Comment: 15 pages Latex, 6 eps files included, revised versio

The left atrial appendage in health and disease

Atrial fibrillation (AF) is the commonest sustained cardiac arrhythmiaand results in significant morbidity and mortality. The left atrial appendage (LAA), a small embryonic remnant of the left atrium (LA), has been shown to play a key role in the pathophysiology of AF-related stroke and thromboembolism. As a consequence the LAA, in spite of its meagre size, has been described as ‘our most lethal human attachment’. Despite being a recognised harbinger of disease, the LAA has also been shown to play an important role in health. This review seeks to address our current understanding of this vital structure in both health and disease states

Spatial and Temporal Variations in the Species Composition of Bycatch Collected During a Striped Mullet (Mugil cephalus) Survey

We examined the variations in species composition of bycatch collected in an annual spawning-season survey of striped mullet, Mugil cephalus, in Tampa Bay and Charlotte Harbor, FL. Bycatch was defined as all species captured with the collection gear other than the target species, M. cephalus. Variations between habitat types, between months, and between years in the species composition of bycatch captured 1993-96 in this ongoing survey were examined using a nonparametric analysis of variance based on Bray-Curtis similarities. Mugil cephalus was the dominant species collected in both study areas, representing 16%-100% of the annual catch. Lagodon rhomboides and Arius felis were the most abundant bycatch species in Tampa Bay, and A. felis and Mugil curema were the most abundant bycatch species in Charlotte Harbor. Archosargus probatocephalus, Sciaenops ocellatus, and Cynoscion nebulosus composed the majority of the remaining bycatch species collected. Bycatch species composition was not significantly different between months, although indices of species richness (Margalef\u27s index, d), species diversity (Shannon index, H\u27 ), and evenness (Pielou\u27s index, J\u27) declined from fall to winter in each year. Species composition differed significantly between riverine and bay habitats and between habitats with and without bottom vegetation (seagrass). Samples from seagrass habitats had more L. rhomboides, A. probatocephalus, and S. ocellatus, and samples from habitats without seagrass had more A. felis. Indices of species richness, diversity, and evenness were lowest in 1996 as a result of increased catches of M. cephalus and decreased occurrence of bycatch in survey samples. The implementation of the Florida net ban in 1995 may have brought about this increased abundance of M. cephalus and concomitant decrease in the percentage of bycatch captured in survey samples in 1996