A duopoly Logit model with price competition and strategic compatibility

This paper provides an analysis of compatibility decisions with oligopolistic price setting in a duopoly logit model. We consider a sequential game in which firms first choose whether they supply compatible products and then set the price which is charged. The equilibrium compatibility configuration is the outcome of a trade-off between consumers valuation of compatibility and the loss of product differentiation which is associated with compatibility. Finally, it is shown that firms incentives towards compatibility tend to be socially insufficient.industrial organization ;

A note on compatibility and entry in a circular model of product differentiation

Consider an industry in which network goods are supplied by two horizontally differentiated firms facing the threat of a potential entrant. Firms' dilemma is between occupying the product space by selling very differentiated (incompatible) goods, and supplying compatible goods that offer higher utilities hence can be charged a higher price to consumers but are also closer substitutes. The compatibility-entry-price game is solved backward when firms and consumers are located on a circular product space. It turns out that strong externalities can favour entry, as merging the networks and accommodating entry can be preferred by the incumbents.compatibility

CONNAISSANCES ET RECONNAISSANCE DE L'EXPERT

Les experts sont des acteurs centraux de cette société de la connaissance. L'expert est supposé posséder à la fois les connaissances et le savoir faire qui devraient permettre de résoudre le problème ou nous aider à prendre les bonnes décisions. De plus sa légitimité et ses connaissances sont rassurantes. Il devient la figure emblématique de celui qui non seulement sait, mais sait aussi comment faire, sait conseiller pour les décisions à prendre... Homme de connaissance et d'action, il incarne celui qui sait agir, décider ou conseiller pour décider, en connaissance de cause, et dont la compétence est reconnue. Il a un rapport privilégié non seulement au savoir mais aussi à la décision et à l'action. Notre travail, qui se veut pluridisciplinaire2, aborde la question de l'expert sous un aspect cognitif et un aspect social. D'une part, l'expert possède des connaissances spécialisées et sait les mobiliser pour l'action, et d'autre part, son statut ne peut être dissocié de la légitimité et de la confiance dont il bénéficie. Dans notre analyse des connaissances et des modes de légitimation de l'expert, nous rappellerons d'abord quelques distinctions clefs touchant la question des connaissances pour spécifier, ensuite, celles de l'expert. Dans une troisième partie, nous abordons la question de la légitimité de l'expert. Une typologie illustrée de recours à l'expert nous permettra de préciser et d'affiner notre approche.Expert, connaissance, légitimé, institutions, communautés

FEAST fundamental framework for electronic structure calculations: Reformulation and solution of the muffin-tin problem

In a recent article [1], the FEAST algorithm has been presented as a general purpose eigenvalue solver which is ideally suited for addressing the numerical challenges in electronic structure calculations. Here, FEAST is presented beyond the "black-box" solver as a fundamental modeling framework which can naturally address the original numerical complexity of the electronic structure problem as formulated by Slater in 1937 [2]. The non-linear eigenvalue problem arising from the muffin-tin decomposition of the real-space domain is first derived and then reformulated to be solved exactly within the FEAST framework. This new framework is presented as a fundamental and practical solution for performing both accurate and scalable electronic structure calculations, bypassing the various issues of using traditional approaches such as linearization and pseudopotential techniques. A finite element implementation of this FEAST framework along with simulation results for various molecular systems are also presented and discussed.Comment: 20 pages, 7 figure

A whey protein supplement decreases post-prandial glycemia

<p>Abstract</p> <p>Background</p> <p>Incidence of diabetes, obesity and insulin resistance are associated with high glycemic load diets. Identifying food components that decrease post-prandial glycemia may be beneficial for developing low glycemic foods and supplements. This study explores the glycemic impact of adding escalating doses of a glycemic index lowering peptide fraction (GILP) from whey to a glucose drink.</p> <p>Methods</p> <p>Ten healthy subjects (3M, 7F, 44.4 ± 9.3 years, BMI 33.6 ± 4.8 kg/m²) participated in an acute randomised controlled study. Zero, 5, 10 and 20 g of protein from GILP were added to a 50 g glucose drink. The control (0 g of GILP) meal was repeated 2 times. Capillary blood samples were taken fasting (0 min) and at 15, 30, 45, 60, 90 and 120 minutes after the start of the meal and analyzed for blood glucose concentration.</p> <p>Results</p> <p>Increasing doses of GILP decreased the incremental areas under the curve in a dose dependant manner (Pearson's r = 0.48, p = 0.002). The incremental areas (iAUC) under the glucose curve for the 0, 5, 10, and 20 g of protein from GILP were 231 ± 23, 212 ± 23, 196 ± 23, and 138 ± 13 mmol.min/L respectively. The iAUC of the 20 g GILP was significantly different from control, 5 g GILP and 10 g GILP (p < 0.001). Average reduction in the glucose iAUC was 4.6 ± 1.4 mmol.min/L per gram of ingested GILP.</p> <p>Conclusion</p> <p>Addition of GILP to a oral glucose bolus reduces blood glucose iAUC in a dose dependent manner and averages 4.6 ± 1.4 mmol.min/L per gram of GILP. These data are consistent with previous research on the effect of protein on the glycemic response of a meal.</p

First metatarsophalangeal hemiarthroplasty for hallux rigidus

There is a paucity of objective information in the literature about first metatarsophalangeal (MTP) hemiarthroplasty. The authors postulate that it is a reasonable treatment option for severe hallux rigidus in selected patients. Twenty-two elective first MTP hemiarthroplasties were performed on 20 patients that met the inclusion criteria. Pre- and postoperative evaluations were done using the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score, visual analogue scale (VAS) pain score, range of motion (ROM) measurements, and radiographs. Average ROM and dorsiflexion improved by 15° and 8°, respectively. VAS pain scores improved from 5 to 2.5 after six weeks. Painless ambulation occurred after six weeks, with maximum improvement by six months. After 24 months, two patients had pain at the surgical site interfering with function, leading to an unsatisfactory result that required conversion to arthrodesis. First MTP hemiarthroplasty for severe hallux rigidus can be considered an alternative to fusion in properly selected patients who wish to maintain a functional range of motion

Liver transplantation as a new standard of care in patients with perihilar cholangiocarcinoma?:Results from an international benchmark study

Objective: To define benchmark values for liver transplantation (LT) in patients with perihilar cholangiocarcinoma (PHC) enabling unbiased comparisons.Background: Transplantation for PHC is used with reluctance in many centers and even contraindicated in several countries. Although benchmark values for LT are available, there is a lack of specific data on LT performed for PHC.Methods: PHC patients considered for LT after Mayo-like protocol were analyzed in 17 reference centers in 2 continents over the recent 5-year period (2014–2018). The minimum follow-up was 1 year. Benchmark patients were defined as operated at high-volume centers (≥ 50 overall LT/year) after neoadjuvant chemoradiotherapy, with a tumor diameter &lt;3 cm, negative lymph nodes, and with the absence of relevant comorbidities. Benchmark cutoff values were derived from the 75th to 25th percentiles of the median values of all benchmark centers.Results: One hundred thirty-four consecutive patients underwent LT after completion of the neoadjuvant treatment. Of those, 89.6% qualified as benchmark cases. Benchmark cutoffs were 90-day mortality ≤ 5.2%; comprehensive complication index at 1 year of ≤ 33.7; grade ≥ 3 complication rates ≤ 66.7%. These values were better than benchmark values for other indications of LT. Five-year disease-free survival was largely superior compared with a matched group of nodal negative patients undergoing curative liver resection (n = 106) (62% vs 32%, P &lt; 0.001).Conclusion: This multicenter benchmark study demonstrates that LT offers excellent outcomes with superior oncological results in early stage PHC patients, even in candidates for surgery. This provocative observation should lead to a change in available therapeutic algorithms for PHC.</p