Perceptions of personal risk in tourists’ destination choices: nature tours in Mexico

Terrorism, pandemic diseases, and other threatening events have recently heightened the sense of personal risk for tourists considering international travel. This article addresses the paucity of research assessing perceptions of risk both before and during travel to risky destinations. Tourists on two nature tours in Mexico were interviewed and observed while engaged in the travel. Many types of specific perceived risks were uncovered, including insect-borne disease, traffic accidents, financial losses, and unattained goals. Some correlates of perceived risk were tour company reputation, stage of family life cycle, age, and motivation. Based on the types of perceived risk and the factors, five propositions are discussed. One unexpected proposition addresses the role of age and states that as the perceived years of physical ability to travel decreases, the tolerance for safety risk increases. Another proposes that eco-tourists with intense, destination- specific motivations are more tolerant of travel risk than those with casual and/or social motivations. The article concludes with suggestions for tour industry managers and directions for future research

Successful Operating Strategies in the Performance of U.S.-China Joint Ventures

Evaluations of the performance of international joint ventures (IJVs) in China have produced mixed conclusions. This study sought to uncover performance criteria used by various groups of managers and to identify critical factors in IJV performance in China. Using in-depth case studies, matched data were collected from personal interviews with managers from Chinese and U.S. parent companies, joint venture operating managers from both partners, and government officials from both countries. The performance criteria used by joint venture participants appear to be converging, with profitability emerging as the dominant element. This exploratory study uncovered four important strategic factors in the performance of large, established U.S.-China manufacturing joint ventures. These are controlling decision making, establishing a sales network, retaining interpartner learning, and influencing government officials. The results suggest that the importance of decision-making control is moderated by size of the venture and nationality. Whether the IJV is a part of the government\u27s National Plan also appears to be an important contingency. Managerial implications and directions for future research are provided

Origins and Development of the Product Life Cycle Concept

Underpinnings and recognition of the product life cycle concept are found in the writings of sociologists, anthropologists, economists, and marketers of the last two centuries. The fashion cycle and advertising spiral are antecedents of the well-known graphic form of the PLC that has been discussed for the last forty years

Center-Edge Asymmetry at Hadron Colliders

We investigate the possibility of using the center-edge asymmetry to distinguish graviton exchange from other new physics effects at hadron colliders. Specifically, we study lepton-pair production within the ADD and RS scenarios. At the Tevatron, the graviton-Z interference is the most important contribution to the center-edge asymmetry, whereas at the LHC, the dominant contribution comes from gluon fusion via graviton exchange, which has no analogue at e^+ e^- colliders. We find that spin-2 and spin-1 exchange can be distinguished up to an ADD cut-off scale, M_H, of about 5 TeV, at the 95% CL. In the RS scenario, spin-2 resonances can be identified in most of the favored parameter space.Comment: 23 pages, including figure

Cosmic Ray Signatures from Decaying Gravitino Dark Matter

We study the charged cosmic rays arising from the slow decay of gravitino dark matter within supersymmetric scenarios with trilinear R-parity violation. It is shown that operators of the LLE type can very well account for the recent anomalies in cosmic ray electron and positron data reported by PAMELA, ATIC and Fermi LAT, without violating any other bounds. This scenario will soon be tested by the Fermi LAT data on diffuse gamma ray emission.Comment: To appear in the proceedings of EPS-HEP 2009, Krakow, Polan

Heavy Higgs boson decays in the alignment limit of the 2HDM

The Standard Model (SM)-like couplings of the observed Higgs boson impose strong constraints on the structure of any extended Higgs sector. We consider the theoretical properties and the phenomenological implications of a generic two Higgs doublet model (2HDM). This model constitutes a simple and attractive extension of the SM that is consistent with the observation of the SM-like Higgs boson and precision electroweak observables, while providing a potential new source of CP-violation. In this paper we focus on the so-called Higgs alignment limit of the generic 2HDM, where the neutral scalar field~$H_1$, with the tree-level couplings of the SM Higgs boson, is a mass eigenstate that is aligned in field space with the direction of the Higgs vacuum expectation value. The properties of the two other heavier neutral Higgs scalars, $H_2$ and $H_3$, in the alignment limit of the 2HDM are also elucidated. It is shown that the couplings of $H_2$ and $H_3$ in the alignment limit are tightly constrained and correlated. For example, in the exact alignment limit at tree level, for bosonic final states $\text{BR}(H_{2,3} \to W^+W^-, ZZ, H_1 Z) = 0$ and $\text{BR}(H^\pm \to W^\pm H_1) = 0$, whereas for fermionic final states $\Gamma(H_2 \to f\bar f)/\Gamma(H_3 \to f\bar f) \sim M_2/M_3$ (where $M_\alpha$ is the mass of $H_\alpha$). In some cases, the results of the alignment limit differ depending on whether or not alignment is achieved via the decoupling of heavy scalar states. In particular, in the exact alignment limit without decoupling $\text{BR}(H_{2,3}\to H_1 H_1)=0$, whereas these branching ratios are nonzero in the decoupling regime. Observables that could be used to test the alignment scenario at the LHC are defined and discussed. The couplings of the Higgs bosons away from their exact alignment values are determined to leading order, and some consequences are elucidated.Comment: 44 pages, 1 figure; v2: references added; v3: major clarifications; v4: JHEP versio

Symmetries and Mass Degeneracies in the Scalar Sector

We explore some aspects of models with two and three SU(2) scalar doublets that lead to mass degeneracies among some of the physical scalars. In Higgs sectors with two scalar doublets, the exact degeneracy of scalar masses, without an artificial fine-tuning of the scalar potential parameters, is possible only in the case of the inert doublet model (IDM), where the scalar potential respects a global U(1) symmetry that is not broken by the vacuum. In the case of three doublets, we introduce and analyze the replicated inert doublet model, which possesses two inert doublets of scalars. We then generalize this model to obtain a scalar potential, first proposed by Ivanov and Silva, with a CP4 symmetry that guarantees the existence of pairwise degenerate scalar states among two pairs of neutral scalars and two pairs of charged scalars. Here, CP4 is a generalized CP symmetry with the property that $({\rm CP}4)^n$ is the identity operator only for integer $n$ values that are multiples of 4. The form of the CP4-symmetric scalar potential is simplest when expressed in the Higgs basis, where the neutral scalar field vacuum expectation value resides entirely in one of the scalar doublet fields. The symmetries of the model permit a term in the scalar potential with a complex coefficient that cannot be removed by any redefinition of the scalar fields within the class of Higgs bases (in which case, we say that no real Higgs basis exists). A striking feature of the CP4-symmetric model is that it preserves CP even in the absence of a real Higgs basis, as illustrated by the cancellation of the contributions to the CP violating form factors of the effective ZZZ and ZWW vertices.Comment: 52 pages, 2 figures, second revised version with new material, as published by JHE