Correction Factors for Reactions involving Quark-Antiquark Annihilation or Production

In reactions with $q \bar q$ production or $q\bar q$ annihilation, initial- and final-state interactions give rise to large corrections to the lowest-order cross sections. We evaluate the correction factor first for low relative kinetic energies by studying the distortion of the relative wave function. We then follow the procedure of Schwinger to interpolate this result with the well-known perturbative QCD vertex correction factors at high energies, to obtain an explicit semi-empirical correction factor applicable to the whole range of energies. The correction factor predicts an enhancement for $q\bar q$ in color-singlet states and a suppression for color-octet states, the effect increasing as the relative velocity decreases. Consequences on dilepton production in the quark-gluon plasma, the Drell-Yan process, and heavy quark production processes are discussed.Comment: 25 pages (REVTeX), includes 2 uuencoded compressed postscript figure

Optimal Procurement Contracts with Pre–Project Planning

The paper studies procurement contracts with pre–project investigations in the presence of adverse selection and moral hazard. To model the procurer’s roblem, we extend a standard sequential screening model to endogenous information acquisition with moral hazard. The optimal contract displays systematic distortions in information acquisition. Due to a rent effect, adverse selection induces too much information acquisition to prevent cost overruns and too little information acquisition to prevent false project cancelations. Moral hazard mitigates the distortions related to cost overruns yet exacerbates those related to false negatives. The optimal mechanism is a menu of option contracts that achieves the dual goal of providing incentives for information acquisition and truthful information revelation

A microscopic modeling of phonon dynamics and charge response in metallic BaBiO3_3

We use our recently proposed microscopic modeling in the framework of linear response theory to investigate the complete phonon dispersion, the phonon density of states, certain phonon-induced electronic charge distributions and charge fluctuations (CF's) for anomalous soft modes of metallic BaBiO$_{3}$ in its simple cubic phase where superconductivity with $T_{c}$ up to 32 K appears. The theoretical approach already has been applied successfully to the cuprate high-temperature superconductors (HTSC's), simple ionic crystals (NaCl, MgO) and perovskite oxides (SrTiO$_{3}$, BaTiO$_{3}$). It is well suited for materials with a strong component of ionic binding and especially for "ionic" metals. In particular, the giant phonon anomalies related to the breathing vibration of the oxygen as found experimentally in superconducting doped Ba$_{0.6}$K$_{0.4}$BiO$_{3}$, resembling those observed in the high $T_{c}$ cuprates, are investigated. The origin of these anomalies is explored and attributed to a strong nonlocal coupling of the displaced oxygen ions to CF's of ionic type, essentially of the Bi6s- and Bi6p orbital. This points to the importance of both of these states at the Fermi energy. Starting from an ab-initio rigid ion model (RIM) we calculate the effect on the lattice dynamics and charge response of the most important electronic polarization processes in the material, i.e. CF's and dipole fluctuations (DF's). Taking into account these electronic degrees of freedom in linear response theory, we obtain a good agreement with the measured phonon dispersion and in particular with the strong phonon anomalies.Comment: Additional comparison with the cuprate HTSC's. A slightly shorter version has been published in PR

A Novel Scoring Based Distributed Protein Docking Application to Improve Enrichment

Molecular docking is a computational technique which predicts the binding energy and the preferred binding mode of a ligand to a protein target. Virtual screening is a tool which uses docking to investigate large chemical libraries to identify ligands that bind favorably to a protein target. We have developed a novel scoring based distributed protein docking application to improve enrichment in virtual screening. The application addresses the issue of time and cost of screening in contrast to conventional systematic parallel virtual screening methods in two ways. Firstly, it automates the process of creating and launching multiple independent dockings on a high performance computing cluster. Secondly, it uses a N˙ aive Bayes scoring function to calculate binding energy of un-docked ligands to identify and preferentially dock (Autodock predicted) better binders. The application was tested on four proteins using a library of 10,573 ligands. In all the experiments, (i). 200 of the 1000 best binders are identified after docking only 14% of the chemical library, (ii). 9 or 10 best-binders are identified after docking only 19% of the chemical library, and (iii). no significant enrichment is observed after docking 70% of the chemical library. The results show significant increase in enrichment of potential drug leads in early rounds of virtual screening

Optimal Procurement Contracts with Pre–Project Planning

The paper studies procurement contracts with pre–project investigations in the presence of adverse selection and moral hazard. To model the procurer’s roblem, we extend a standard sequential screening model to endogenous information acquisition with moral hazard. The optimal contract displays systematic distortions in information acquisition. Due to a rent effect, adverse selection induces too much information acquisition to prevent cost overruns and too little information acquisition to prevent false project cancelations. Moral hazard mitigates the distortions related to cost overruns yet exacerbates those related to false negatives. The optimal mechanism is a menu of option contracts that achieves the dual goal of providing incentives for information acquisition and truthful information revelation.Information acquisition; procurement; dynamic mechanism design

A critical evaluation of the standardisation potential of business plan evaluation aids (BPEA) used in venture capital investment decision-making

The research objective was to perform a critical evaluation and comparison of four, representative Business Plan Evaluation Aids (BPEA) to facilitate constructive discussion of the proposition that greater standardisation of venture capital decision-making might be both desirable and possible.The four BPEA were systematically compared using a structured, taxonomic process employing seven key criteria. The evidence of this investigation suggests a clear superiority for BPEAs, which are based on the known attributes of successful ventures and use actuarial modelling. Discussion centred on the importance of using BPEAs in a quest for greater consistency of venture capital investment decision-making.<br /

Modified Stage-Gate: A Conceptual Model of Virtual Product Development Process

In today s dynamic marketplace, manufacturing companies are under strong pressure to introduce new products for long-term survival with their competitors. Nevertheless, every company cannot cope up progressively or immediately with the market requirements due to knowledge dynamics being experienced in the competitive milieu. Increased competition and reduced product life cycles put force upon companies to develop new products faster. In response to these pressing needs, there should be some new approach compatible in flexible circumstances. This paper presents a solution based on the popular Stage-Gate system, which is closely linked with virtual team approach. Virtual teams can provide a platform to advance the knowledge-base in a company and thus to reduce time-to-market. This article introduces conceptual product development architecture under a virtual team umbrella. The paper describes all the major aspects of new product development (NPD), NPD process and its relationship with virtual teams, Stage-Gate system finally presents a modified Stage-Gate system to cope up with the changing needs. It also provides the guidelines for the successful implementation of virtual teams in new product development.Comment: 24 page

1S0 Proton and Neutron Superfluidity in beta-stable Neutron Star Matter

We investigate the effect of a microscopic three-body force on the proton and neutron superfluidity in the $^1S_0$ channel in $\beta$-stable neutron star matter. It is found that the three-body force has only a small effect on the neutron $^1S_0$ pairing gap, but it suppresses strongly the proton $^1S_0$ superfluidity in $\beta$-stable neutron star matter.Comment: 12 pages, 2 figure

Modified Stage-Gate: A Conceptual Model of Virtual Product Development Process

In today’s dynamic marketplace, manufacturing companies are under strong pressure to introduce new products for long-term survival with their competitors. Nevertheless, every company cannot cope up progressively or immediately with the market requirements due to knowledge dynamics being experienced in the competitive milieu. Increased competition and reduced product life cycles put force upon companies to develop new products faster. In response to these pressing needs, there should be some new approach compatible in flexible circumstances. This paper presents a solution based on the popular Stage-Gate system, which is closely linked with virtual team approach. Virtual teams can provide a platform to advance the knowledge-base in a company and thus to reduce time-to-market. This article introduces conceptual product development architecture under a virtual team umbrella. The paper describes all the major aspects of new product development (NPD), NPD process and its relationship with virtual teams, Stage-Gate system finally presents a modified Stage-Gate system to cope up with the changing needs. It also provides the guidelines for the successful implementation of virtual teams in new product development