‘Guaranteed lowest prices: do they facilitate collusion?’: Revisited

We examine the effect of guaranteed lowest price clauses (G.L.P.). First, we correct the proof of Logan and Lutter’s main result that it is the unique equilibrium outcome for firms adopting G.L.P. to charge collusive prices in a simultaneous pricing game, if one uses the trembling-hand perfect equilibrium as the solution concept. Second, we extend their argument to a sequential pricing game in which one firm chooses its price before the other, given that both firms adopt G.L.P. We show that collusive prices is the unique equilibrium outcome in this game even without resorting to any stringent refinement like the trembling-hand perfect equilibrium

Strategic delegation and second mover advantage in duopoly

We consider a duopoly in which each firm has one owner and one manager playing a multi-stage delegation game. The decision of each firm consists of two stages. In the first stage, the owner offers his manager a contract based on profits and sales. In the second stage, the manager chooses its output or price. Several possible sequential games will be analysed, depending on the sequence of the strategic variables. In the first scenario in which firm 1 makes a contract decision and a producing decision sequentially, and firm 2 follows in the same fashion, we show that any delegation equilibrium in which both owners commit their managers to profit-maximising behaviour disappears. In the second scenario in which the firms first enter into the contract stage and then Stackelberg competition follows in the second stage, sales-based delegation occurs. If firms compete in quantities, second mover advantage appears if firms make simultaneous delegation contracts, while first mover advantage is recovered if they make sequential contracts. If firms compete in prices, the results are reversed

Expression of Functional Recombinant Mussel Adhesive Protein Mgfp-5 in Escherichia coli

Mussel adhesive proteins have been suggested as a basis for environmentally friendly adhesives for use in aqueous conditions and in medicine. However, attempts to produce functional and economical recombinant mussel adhesive proteins (mainly foot protein type 1) in several systems have failed. Here, the cDNA coding for Mytilus galloprovincialis foot protein type 5 (Mgfp-5) was isolated for the first time. Using this cDNA, we produced a recombinant Mgfp-5 fused with a hexahistidine affinity ligand, which was expressed in a soluble form in Escherichia coli and was highly purified using affinity chromatography. The adhesive properties of purified recombinant Mgfp-5 were compared with the commercial extracted mussel adhesive Cell-Tak by investigating adhesion force using atomic force microscopy, material surface coating, and quartz crystal microbalance. Even though further macroscale assays are needed, these microscale assays showed that recombinant Mgfp-5 has significant adhesive ability and may be useful as a bioadhesive in medical or underwater environments.X119196sciescopu

Organic-inorganic nanocomposite membranes from highly ordered mesoporous thin films for solubility-based separations

Solubility-based membrane separation, in which the more soluble species preferentially permeates across the membrane, has attracted considerable recent attention due to both economic and environmental concerns. This solubility-selective mode is particularly attractive over a diffusivity-selective mode in applications in which the heavier species are present in dilute concentrations. Examples include the recovery of volatile organic components (VOCs) from effluent streams and the removal of higher hydrocarbons from natural gas. Recently, nanocomposites have shown great promise as possible membrane materials for solubility-selective separations. The chemical derivatization of inorganic mesoporous substrates has been explored to synthesize organic-inorganic nanocomposite membranes. The most exciting feature of this approach is that it enables the rational engineering of membrane nano-architecture with independent control over the free volume and chemistry to create membranes with highly customizable permselectivity properties. In this study, we synthesized the organic-inorganic nanocomposite membranes by decorating the surfaces of commercially available mesoporous alumina substrates, and surfactant-templated highly ordered mesoporous silicate thin films placed on commercially available macroporous inorganic substrates, with a selective organic material that is physically or chemically anchored to the porous surfaces. Hyperbranched melamine-based dendrimers, with nanometer dimension and chemical composition designed to target certain components, were used as filling agents. We evaluated these membranes for several environmentally relevant separations, such as the recovery of the higher hydrocarbon from air and the removal of trace VOCs from air or water, while exploring the impact of organic oligomer size, chemistry, and surface coverage, as well as substrate pore size and structure, on membrane performance. First, we did a model study to verify the feasibility of dendrimer growth inside mesopores by using ordered mesoporous silica. Alumina-ordered mesoporous silica (alumina-OMS) hybrid membranes were prepared as new inorganic porous substrates. Finally, we synthesized dendrimer-ceramic nanocomposite membranes by growing several generations of melamine-based dendrimers with diverse functional groups directly off the commercial alumina membranes. Composite membranes show very high propane/nitrogen selectivity up to 70

Analysis of truckload prices and rejection rates

Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (p. 60).Truckload (TL) is the principle mode of freight transportation in the United Sates. Buyers of TL services are shippers with significant amount of shipments throughout a year. Due to the complexity of their network and the large expenditure on transportation, shippers select their carriers through auctions and using optimization methods, and enter into long-term contracts with winners with the best prices. Shippers subsequently request their carriers to fulfill shipment every time there's a load, a procedure called 'tender'. Despite the sophisticated selection and the existence of contracts, shippers' tenders are frequently rejected by their carriers, a phenomenon called tender rejection. When this happens, the shipper has to find alternative carriers and most of the time the price for the load increases. With weekly rejection rate as a dependent variable, and with variability of volume, length of haul, or the differential in prices as independent variables, this research mainly used the linear regression method to examine how well these independent variables account for rejections for a given lane. The analysis used the data including TL shipment and tender records of 17 shippers for five years. This research also attempted to discover any geographic patterns of frequent rejections. The analysis of the relationship between truckload rates and rejection rates suggested a potential trade-off between price and rejection, which questions the generally accepted strategy of shippers minimizing truckload expenditures by unconditionally reducing rejections.by Yoo Joon Kim.M.Eng.in Logistic

Perspectives of CB1 Antagonist in Treatment of Obesity: Experience of RIO-Asia

Rimonabant, a selective cannabinoid-1 (CB1) receptor antagonist, has been shown to reduce weight and enhance improvements in cardiometabolic risk parameters in Western populations. This study assessed these effects of rimonabant in Asian population. A total of 643 patients (BMI 25 kg/m2 or greater without diabetes) from China, Republic of Korea, and Taiwan were prescribed a hypocaloric diet (600 kcal/day deficit) and randomized to rimonabant 20 mg (n = 318) or placebo (n = 325) for 9months. The primary efficacy variable was weight change from baseline after 9 months of treatment. Results showed that rimonabant group lost more weight than placebo, (LSM ± SEM of −4.7 ± 0.3 kg vs. −1.7 ± 0.3 kg, P < .0001). The 5% and 10% responders were 2 or 3 folds more in the rimonabant group (53.0% vs. 20.0% and 21.5% vs. 5.7%, resp.) (P < .0001). Rimonabant also significantly increased HDL-cholesterol, decreased triglycerides and waist circumference,by 7.1%, 10.6%, and 2.8 cm, respectively (P < .0001). This study confirmed the comparable efficacy and safety profile of rimonabant in Asian population to Caucasians. Owing to the recent suspension of all the CB1 antagonists off the pharmaceutical market for weight reduction in Europe and USA, a perspective in drug discovery for intervening peripheral CB1 receptor in the management of obesity is discussed