Port Investments on Coastal and Marine Disasters Prevention: An Economic and Policy Investigation

Located along shorelines, seaports are highly vulnerable to coastal and marine natural disasters. Damage caused by disasters can be prevented or alleviated if sufficient investments are made in a timely manner. However, despite a wide range of investment options and well-developed engineering expertise, port investment on disaster prevention remains a challenging task involving great complexities. This paper develops an integrated economic model for the analysis of disaster-prevention investments at a “landlord” port. It simultaneously considers the uncertainty of disaster occurrence and associated return of prevention investments, the information accumulation and related investment timing, and the spillovers (externalities) of investment among stakeholders. Our analysis shows that the timing of port investments depends on the probability of disasters. Immediate investment is optimal for disasters with very high probability, while investment should be postponed if such a probability is very low. Optimal timing for cases of intermediate probability cannot be determined analytically, as it is influenced by other factors such as discount rate, information accumulation and efficiency of investments. Positive externalities between a port and its tenants lead to under-investment, which can be corrected by coordination between stakeholders. However, since there are risks of “over-investment” due to uncertainty, government intervention is only optimal with a good understanding of disaster probability distribution

Prokaryotic expression, purification and immunogenicity analysis of CpsD protein from Streptococcus iniae

Streptococcus iniae is a major cause of serious bacterial infections in both fish and human beings. Capsular polysaccharide (CPS) of S. iniae is vital to evade phagocytic clearance of the host and serves as an important protective antigen of S. iniae infection in aquatic animals. The CpsD gene was determined to be highly conservative in capsule polysaccharide operon. Prokaryotic expression of the CpsD gene of a clinical isolate of S. iniae from channel catfish and immunogenic examination of the recombinant protein were first described in this essay. The recombinant protein was expressed in the form of inclusion bodies (IBs). Induction conditions in Escherichia coli were optimized with 0.6mM Isopropyl β-D-1-Thiogalactopyranoside at 37°C for 5h after the culture mid-log phase in Luria Bertani (LB) medium. The recombinant protein CpsD was thus expressed and purified by immobilized metal affinity chromatography (IMAC), yielding approximate 582.47 mg the protein per liter culture. Western blot analysis showed that the purified CpsD had reactogenicity. It will possibly reveal more details of capsule synthesis and capsule regulation during various stages of the S. iniae infectious process

Berry Curvature in Graphene: A New Approach

In the present paper we have directly computed the Berry curvature terms relevant for Graphene in the presence of an \textit{inhomogeneous} lattice distortion. We have employed the generalized Foldy Wouthuysen framework, developed by some of us \cite{ber0,ber1,ber2}. We show that a non-constant lattice distortion leads to a valley-orbit coupling which is responsible to a valley-Hall effect. This is similar to the valley-Hall effect induced by an electric field proposed in \cite{niu2} and is the analogue of the spin-Hall effect in semiconductors \cite{MURAKAMI, SINOVA}. Our general expressions for Berry curvature, for the special case of homogeneous distortion, reduce to the previously obtained results \cite{niu2}. We also discuss the Berry phase in the quantization of cyclotron motion.Comment: Slightly modified version, to appear in EPJ

Topcolor-Assisted Supersymmetry

It has been known that the supersymmetric flavor changing neutral current problem can be avoided if the squarks take the following mass pattern, namely the first two generations with the same chirality are degenerate with masses around the weak scale, while the third generation is very heavy. We realize this scenario through the supersymmetric extension of a topcolor model with gauge mediated supersymmetry breaking.Comment: 12 pages, latex, no figure

Direct Signals for Large Extra Dimensions in the Production of Fermion Pairs at Linear Colliders

We analyze the potentiality of the new generation of $e^+e^-$ linear colliders to search for large extra dimensions via the production of fermion pairs in association with Kaluza-Klein gravitons (G), i.e. $e^+e^- \leftarrow f\bar{f}G$. This process leads to a final state exhibiting a significant amount of missing energy in addition to acoplanar lepton or jet pairs. We study in detail this reaction using full tree level contibutions due to the graviton emission and the standard model backgrounds. After choosing the cuts to enhance the signal, we show that a linear collider with a center-of-mass energy of 500 GeV will be able to probe quantum gravity scales from 0.96(0.86) up to 4.1(3.3) TeV at 2(5)$\sigma$ level, depending on the number of extra dimensions.Comment: 19 pages, 5 figures. Using RevTex, axodraw.sty. Discussion was extended. No changes in the results. Accepted for publication by Phys. Rev.

Danggui Buxue Tang – A Chinese herbal decoction activates the phosphorylations of extracellular signal-regulated kinase and estrogen receptor α in cultured MCF-7 cells

AbstractDanggui Buxue Tang (DBT), a Chinese herbal decoction used to treat ailments in women, contains Radix Astragali (Huangqi; RA) and Radix Angelicae Sinensis (Danggui; RAS). The weight ratio of RA to RAS used in DBT must be 5:1 as stipulated as early as AD 1247; however, DBT’s mechanism of action has never been described. Here, the estrogenic effects of DBT were investigated by determining the phosphorylations of estrogen receptor α (ERα) and extracellular signal-regulated kinase 1/2 (Erk1/2) in cultured MCF-7 cells. The application of DBT triggered the phosphorylation of ERα and Erk1/2 in a time-dependent manner. In contrast to the effect of estrogen, DBT triggered ERα phosphorylation at both S118 and S167. This DBT-specific phosphorylation was not triggered by an extract of one of the individual herbs, or by mixing the extracts of RA and RAS. DBT-induced downstream signals are described here. These signals suggest the uniqueness of this Chinese herbal decoction that requires a well-defined formulation

Probing interaction and spatial curvature in the holographic dark energy model

In this paper we place observational constraints on the interaction and spatial curvature in the holographic dark energy model. We consider three kinds of phenomenological interactions between holographic dark energy and matter, i.e., the interaction term $Q$ is proportional to the energy densities of dark energy ($\rho_{\Lambda}$), matter ($\rho_{m}$), and matter plus dark energy ($\rho_m+\rho_{\Lambda}$). For probing the interaction and spatial curvature in the holographic dark energy model, we use the latest observational data including the type Ia supernovae (SNIa) Constitution data, the shift parameter of the cosmic microwave background (CMB) given by the five-year Wilkinson Microwave Anisotropy Probe (WMAP5) observations, and the baryon acoustic oscillation (BAO) measurement from the Sloan Digital Sky Survey (SDSS). Our results show that the interaction and spatial curvature in the holographic dark energy model are both rather small. Besides, it is interesting to find that there exists significant degeneracy between the phenomenological interaction and the spatial curvature in the holographic dark energy model.Comment: 11 pages, 5 figures; to appear in JCA

An Approach to Elastoplasticity at Large Deformations

Finite plasticity theories are still a subject of controversy and lively discussions. Among the approaches to finite elastoplasticity two became especially popular. The first, implemented in the commercial finite element codes, is based on the introduction of a hypoelastic constitutive law and the additive elastic-plastic decomposition of the deformation rate tensor. Unfortunately, the use of hypoelasticity may lead to a nonphysical creation or dissipation of energy in a closed deformation cycle. In order to replace hypoelasticity with hyperelasticity the second popular approach based on the multiplicative elastic-plastic decomposition of the deformation gradient tensor was developed. Unluckily, the latter theory is not perfect as well because it introduces intermediate plastic configurations, which are geometrically incompatible, non-unique, and, consequently, fictitious physically. In the present work, an attempt is made to combine strengths of the described approaches avoiding their drawbacks. Particularly, a tensor of the plastic deformation rate is introduced in the additive elastic-plastic decomposition of the velocity gradient. This tensor is used in the flow rule defined by the generalized isotropic Reiner-Rivlin fluid. The tensor of the plastic deformation rate is also used in an evolution equation that allows calculating an elastic strain tensor which, in its turn, is used in the hyperelastic constitutive law. Thus, the present approach employs hyperelasticity and the additive decomposition of the velocity gradient avoiding nonphysical hypoelasticity and the multiplicative decomposition of the deformation gradient associated with incompatible plastic configurations. The developed finite elastoplasticity framework for isotropic materials is specified to extend the classical -theory of metal plasticity to large deformations and the simple shear deformation is analyzed

Managing to lead in private enterprise in China: Work values, demography and the development of trust

Previous work on trust has focused on employee trust in management. However, issues of how leaders develop trust in their followers in leader-member exchange (LMX) are under-explored. Based on theories of leader-member exchange, attribution and industrial convergence, this study investigates how the work values of leaders influence the development of their trust in followers and how this is moderated by demographic factors. A survey of 219 leaders was conducted in privately owned enterprises in China. The findings suggest that the work value of centralization is negatively related to leader trust in follower predictability. Group orientation and formalization are positively related to the development of trust in follower good faith. Moreover, age and level of formal education are found to moderate significantly the relationships between leader work values and development of their trust in followers within the context of China. Copyright © 2007 SAGE Publications

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe