Incentive Stackelberg Mean-payoff Games

We introduce and study incentive equilibria for multi-player meanpayoff games. Incentive equilibria generalise well-studied solution concepts such as Nash equilibria and leader equilibria (also known as Stackelberg equilibria). Recall that a strategy profile is a Nash equilibrium if no player can improve his payoff by changing his strategy unilaterally. In the setting of incentive and leader equilibria, there is a distinguished player called the leader who can assign strategies to all other players, referred to as her followers. A strategy profile is a leader strategy profile if no player, except for the leader, can improve his payoff by changing his strategy unilaterally, and a leader equilibrium is a leader strategy profile with a maximal return for the leader. In the proposed case of incentive equilibria, the leader can additionally influence the behaviour of her followers by transferring parts of her payoff to her followers. The ability to incentivise her followers provides the leader with more freedom in selecting strategy profiles, and we show that this can indeed improve the payoff for the leader in such games. The key fundamental result of the paper is the existence of incentive equilibria in mean-payoff games. We further show that the decision problem related to constructing incentive equilibria is NP-complete. On a positive note, we show that, when the number of players is fixed, the complexity of the problem falls in the same class as two-player mean-payoff games. We also present an implementation of the proposed algorithms, and discuss experimental results that demonstrate the feasibility of the analysis of medium sized games.Comment: 15 pages, references, appendix, 5 figure

Inverse Methods for Load Identification Augmented By Optimal Sensor Placement and Model Order Reduction

Design problems require accurate characterization of loads acting on a structure. One way to estimate the loads is through experimentally measured structural response. This is known as the inverse problem. The instrumented structure essentially acts as its own transducer. It is well known that the inverse problems tend to be highly ill-conditioned. This dissertation proposes several novel time domain and modal domain algorithms for estimating multiple dynamic loads exciting a structure from structural response measured at a finite number of optimally placed non-collocated sensors on the structure. The optimal placement of sensors is necessary to counter the inherent limitation of such inverse problems - ill-conditioning. Solution procedures based on construction of D-optimal design as well as sparse nature of mass, damping and stiffness matrices are proposed and implemented to determine the optimum locations of sensors that will provide the most precise load estimates. Both strain measurements using strain gages and acceleration measurements using accelerometers have been given due attention. Improvements in the load identification algorithms, based on model order reduction and reduced modal parameters, are further proposed to reconstruct the input forces accurately. Load identification techniques based on dynamic programming and Markov parameters have also been studied in this work. Several limitations to these existing techniques have been identified. An attempt has been made in this dissertation to address the identified shortcomings based on D-optimal design for obtaining optimal sensor locations on the structure and model order reduction for computational cost reduction. Both experimental measurements as well as numerical simulations have been performed in order to validate the proposed techniques. The experimental validation is done using a simple beam clamped at the base and attached to a shaker head. The focus of this example is to reconstruct the input forces exciting the structure through the shaker head. Numerical simulations are performed on the computational models developed in finite element tool ANSYS that works in close conjunction with MATLAB. Numerical sensitivity analyses are further performed to study the effect of uncertainties (noise) in experimental data as well as in the model; the techniques are validated to be robust - even with the presence of noise, the applied loads are recovered accurately

Awareness and Compliance in Contact Lens Wearers: Case Study

Purpose: To assess the contact lens compliance rate by using a self-administrated validated questionnaire, the level of awareness, compliance & detectable behavioral changes, patterns or trends in contact lens users. Methods: A questionnaire ,Cross sectional prospective study to understand the compliance in contact lens wearers, the questionnaires were distributed randomly among the users at various clinical & optical outlets. Based on various studies, and taking into account time constraints the sample size of 40 was taken. The mean age of 24 years was taken without any ocular pathology and systemic disease affecting the ocular health. Result: The majority of 87% of the subjects studied, preferred the monthly modality and 13 % preferred conventional yearly replacement lenses. Considering average duration of wear 64% of the subjects showed non- compliance and prolonged their wearing schedules beyond 8 hours. 38% of the contact lens users were not taking optimum care of the lens cases. A majority of 50% of the subjects rated better cosmetic appearance the most important factor, while 25% of them rated cosmetic & better vision equally important. 68% knew the availability of extended wear contact lenses that can be worn during sleep. Optical outlets are the places where the patient is more motivated for soft contact lens. Conclusion: Cost and convenience are two factors that must be considered when educating patients about proper lens care regimens. In addition, compliance is more likely if the patient is satisfied with the medical visit

Geranyl acetate esterase (GAE) inhibitory activity of Neolamarckia cadamba fruit extract

Neolamarckia cadamba commonly known as the kadamb tree-is well known in Ayurveda and other traditional literature in India for it’s plenty of medicinal properties. Here we report the unique property of the methanol extract of its fruit and a compound isolated from it to inhibit the geranyl acetate esterase (GAE) of lemongrass. The GAE inhibitory activities of the methanol extract and the compound were determined by three procedures, spectrophotometric para-nitrophenyl acetate (p-NPA) assay, polyacrylamide gel electrophoresis (PAGE) and gas chromatography (GC). The results of p-NPA assay revealed that the fruit extract and its compound (10 mg/ml) caused significant inhibition (45%) of GAE activity as compared to the control. PAGE analysis revealed complete inhibition of one of the major isoenzyme of GAE (isoenzyme-II) by both the fruit extract and its isolated constituent. Gas chromatographic analysis showed the fruit extract and its compound caused drastic inhibition of GAE isoenzyme-II by 36 and 46%, respectively. The presence of –C=O and –OH groups in the compound as revealed by FTIR analysis indicated that it belongs to flavonoids. To the best of our knowledge this is the first report on GAE inhibitory activity of N. cadamba fruit methanol extract and its isolated constituent which could be implicated in the future to decipher the catalytic mechanism of GAE. The purification and detailed characterization of the isolated compound is in progress

A study on development changes in essential oil content and composition in Cymbopogon flexuosus cultivar Suvarna

Cymbopogon flexuosus (Steud.) cv. Suvarna produces an essential oil with unique lemon like aroma which is broadly used in flavors, fragrance, perfumery and pharmaceuticals. Here we report changes in essential oil content and compositions during C. flexuosus cv. Suvarna leaf development, leaf positions and leaf age. Essential oils were isolated by hydro-distillation of leaves harvested at six different developmental stages (10-50 days), 1st-5th leaf positions and three parts (basal, middle and apical) of the leaves. Analyses of essential oils by gas chromatography and GC-MS have identified 20 different terpenoids constituents with citral as the major monoterpene. The study showed that essential oil content was highest in early stages (10-20 days) of leaf development, then declined substantially. Similar pattern of essential oil content was observed between the 1st-5th leaf positions and the basal-apical parts within a leaf. Essential oil compositions were also markedly fluctuated. Percentage together of geranyl acetate and geraniol declined rapidly from 32% to 4% on 10th and 20th days, respectively; while percentage of citral (geranial + neral) increased correspondingly from 56% to 81% on 10th and 20th days, respectively. Similar changes in monoterpene composition were observed in leaf positions and leaf age (basal to apical part). Thus the study revealed that accumulation of essential oil depends on the developmental stages of the concerned plant parts and changes in essential oil content is also reflected by compositional changes in oil constituents

Neutrophil-to-lymphocyte ratio as predictor of nausea and vomiting after elective laparoscopic cholecystectomy

Background: The neutrophil-lymphocyte ratio (NLR) or platelet-lymphocyte ratio (PLR) has been proposed as a parameter for the diagnosis of inflammatory diseases in different studies; however, the literature does not discuss this relationship for elective laparoscopic cholecystectomy. The purpose of this study was to determine whether preoperative NLR or PLR is associated with postoperative nausea and vomiting (PONV), one of the most common postoperative complications and whether it may act as a biomarker for the illness. Methods: The clinical data of 146 patients with symptomatic cholelithiasis who underwent elective laparoscopic cholecystectomy (ELC) at our institution were collected and analyzed. Results: We divided patients into PONV and No-PONV groups. and logistic regression analysis was used to identify predictors for PONV. In logistic regression analysis, the preoperative neutrophil-to-lymphocyte ratio (NLR) [odds ratio (OR): 1.61, 95% confidence interval (CI), p=0.01] was identified as an independent risk factor for the presence of PONV. On ROC analysis, the success of NLR in discriminating PONV was found to be statistically significant [area under curve (AUC)=0.631, p=0.01]. Conclusions: PONV can be predicted in patients undergoing ELC with NLR. As a result, blood parameters should be examined to enhance these patients’ post-operative recovery period

Comparative Evaluation of the Complementary and Alternative Medicine Therapy and Conventional Therapy Use for Musculoskeletal Disorders Management and Its Association with Job Satisfaction among Dentists of West India

ABSTRACTMusculoskeletal problems have become a significant issue in the profession of dentistry. There are currently no recommended effective disease-preventing and modifying remedies. High prevalence rates for musculoskeletal disorders (MSDs) among dentists have been reported in the literature. Complementary and alternative medicine can be helpful in managing and preventing the MSDs. The purpose of this study was to determine if dentists in the western part of India are using complementary and alternative medicine therapies for MSDs, and also to find if those who use complementary and alternative medicine therapies have greater job/career satisfaction compared to conventional therapy (CT) users. Dentists of western India registered under the Dental Council of India (N=2166) were recruited for the study. Data were analyzed using univariate and bivariate analyses and logistic regression. A response rate of 73% (n=1581) was obtained, of which 79% (n=1249) was suffering from MSDs. The use of complementary and alternative medicine or CT was reported by 90% (n=1124) of dentists with MSDs. Dentists using complementary and alternative medicine reported greater health (P<0.001) and carrier satisfaction (P<0.001) and were able to work as many hours they wanted (P<0.001) compared to CT users. Complementary and alternative medicine therapies may improve the quality of life and enhance job satisfaction for a dentist who suffers from MSDs