Simulation of continuous variable quantum games without entanglement

A simulation scheme of quantum version of Cournot's Duopoly is proposed, in which there is a new Nash equilibrium that may be also Pareto optimal without any entanglement involved. The unique property of this simulation scheme is decoherence-free against the symmetric photon loss. Furthermore, we analyze the effects of the asymmetric information on this simulation scheme and investigate the case of asymmetric game caused by asymmetric photon loss. A second-order phase transition-like behavior of the average profits of the firm 1 and firm 2 in Nash equilibrium can be observed with the change of the degree of asymmetry of the information or the degree of "virtual cooperation". It is also found that asymmetric photon loss in this simulation scheme plays a similar role with the asymmetric entangled states in the quantum game. PACS numbers: 02.50.Le, 03.67.-aComment: 7 pages, 4 figures, RevTex, some contents have been revise

Variability in lipid profile in patients with acute myocardial infarction from two tertiary care hospitals in Pakistan

Objective: To investigate changes in total cholesterol, high density lipoprotein (HDL)-cholesterol, low density lipoprotein (LDL)-cholesterol and triglycerides in serum of Pakistani patients with AMI due to age, gender, body mass index (BMI), diabetes, hypertension, and smoking, and also find out the prevalence of hypercholesterolemia, hypertriglyceridemia, low HDL-cholesterol and isolated low-HDL cholesterol in them.Patients and Methods: Serum samples from 451 consecutive AMI patients (250 from National Institute of Cardiovascular Diseases, Karachi and 201 from Armed Forces Institute of Cardiology, Rawalpindi) were analyzed for total cholesterol, HDL-cholesterol and triglycerides using kit methods. LDL-cholesterol was determined using the Friedewald formula.Results: Mean serum concentrations of total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides in AMI patients were found to be 181 +/- 50 mg/dl, 35.7 +/- 11.3 mg/dl, 110 +/- 47 mg/dl and 177 +/- 127 mg/dl, respectively. Mean levels of total cholesterol and HDL-cholesterol were not significantly affected by age, gender, BMI, diabetes mellitus, hypertension and smoking. Mean LDL-cholesterol concentration, however, was found to be significantly increased in diabetes mellitus (p=0.047), while age, gender, BMI, hypertension and smoking had no significant effect on the levels of this lipoprotein. Mean levels of triglycerides were significantly decreased in older patients (\u3e50 years) compared to younger (\u3c50 \u3eyears) ones (p=0.019). Gender, BMI, diabetes mellitus, hypertension and smoking, however, had no effect on triglyceride levels The frequencies of hypercholesterolemia, hypertriglyceridemia, low HDL-cholesterol and isolated low-HDL-cholesterol were found to be 30.6%, 30.1%, 48.6% and 34.1%, respectively.Conclusion: High prevalence of hypertriglyceridemia and low HDL-cholesterol (which constitute a component of metabolic syndrome) in Pakistani AMI patients is suggestive that these two lipid abnormalities could be playing a major role in the development of atherosclerosis in Pakistani population

Risk factors and behaviours for coronary artery disease (CAD) among ambulatory Pakistanis

Objective: To determine the frequency and distribution of various risk factors and behaviours for coronary artery disease (CAD) among ambulatory Pakistanis.Methods: It is a cross-sectional descriptive study carried out at the Aga Khan University Hospital, a teaching hospital in Karachi. All the subjects were adults (18-60 years) presenting at the general checkup clinic with no history or evidence of CAD by convenient sampling method. Demographic variables included risk factors and behaviors including diabetes, hypertension, dyslipidemia, family history of heart disease, obesity, smoking and sedentary lifestyle.Results: Among 370 ambulatory Pakistanis, the proportions of major risk factors for CAD were: sedentary life style 72%, family history 42%, dyslipidemia 31%, obesity 24%, hypertension 19% and diabetes mellitus 15%. Diabetes, hypertension and dyslipidemia were poorly controlled in the study population. Proportions of the three major risk factors (smoking, hypertension and dyslipidemia) occurring singly, doubly and all three together in the study population were found to be 39%, 11% and 1%, respectively. Data were also analyzed for risk factors by comparing those with and without family history of CAD to eliminate any bias. The results were not statistically significant except for the sedentary life style (P=0.016).Conclusion: There is a high prevalence of CAD risk factors in this study population. Modifiable risk factors like diabetes, hypertension and high cholesterol need better control. Preventive screening programs and healthy lifestyle behaviours need to be emphasized upon in the community

Quantum Matching Pennies Game

A quantum version of the Matching Pennies (MP) game is proposed that is played using an Einstein-Podolsky-Rosen-Bohm (EPR-Bohm) setting. We construct the quantum game without using the state vectors, while considering only the quantum mechanical joint probabilities relevant to the EPR-Bohm setting. We embed the classical game within the quantum game such that the classical MP game results when the quantum mechanical joint probabilities become factorizable. We report new Nash equilibria in the quantum MP game that emerge when the quantum mechanical joint probabilities maximally violate the Clauser-Horne-Shimony-Holt form of Bell's inequality.Comment: Revised in light of referees' comments, submitted to Journal of the Physical Society of Japan, 14 pages, 1 figur

Quantum correlation games

A new approach to play games quantum mechanically is proposed. We consider two players who perform measurements in an EPR-type setting. The payoff relations are defined as functions of correlations, i.e. without reference to classical or quantum mechanics. Classical bi-matrix games are reproduced if the input states are classical and perfectly anti-correlated, that is, for a classical correlation game. However, for a quantum correlation game, with an entangled singlet state as input, qualitatively different solutions are obtained. For example, the Prisoners' Dilemma acquires a Nash equilibrium if both players apply a mixed strategy. It appears to be conceptually impossible to reproduce the properties of quantum correlation games within the framework of classical games

Electron-phonon interaction in the solid form of the smallest fullerene C20_{20}

The electron-phonon coupling of a theoretically devised carbon phase made by assembling the smallest fullerenes C$_{20}$ is calculated from first principles. The structure consists of C$_{20}$ cages in an {\it fcc} lattice interlinked by two bridging carbon atoms in the interstitial tetrahedral sites ({\it fcc}-C$_{22}$). The crystal is insulating but can be made metallic by doping with interstitial alkali atoms. In the compound NaC$_{22}$ the calculated coupling constant $\lambda/N(0)$ is 0.28 eV, a value much larger than in C$_{60}$, as expected from the larger curvature of C$_{20}$. On the basis of the McMillan's formula, the calculated $\lambda$=1.12 and a $\mu^*$ assumed in the range 0.3-0.1 a superconducting T$_c$ in the range 15-55 K is predicted.Comment: 7 page

Bayesian Nash Equilibria and Bell Inequalities

Games with incomplete information are formulated in a multi-sector probability matrix formalism that can cope with quantum as well as classical strategies. An analysis of classical and quantum strategy in a multi-sector extension of the game of Battle of Sexes clarifies the two distinct roles of nonlocal strategies, and establish the direct link between the true quantum gain of game's payoff and the breaking of Bell inequalities.Comment: 6 pages, LaTeX JPSJ 2 column format, changes in sections 1, 3 and 4, added reference

Variability in H9N2 haemagglutinin receptor-binding preference and the pH of fusion

H9N2 avian influenza viruses are primarily a disease of poultry; however, they occasionally infect humans and are considered a potential pandemic threat. Little work has been performed to assess the intrinsic biochemical properties related to zoonotic potential of H9N2 viruses. The objective of this study, therefore, was to investigate H9N2 haemagglutinins (HAs) using two well-known correlates for human adaption: receptor-binding avidity and pH of fusion. Receptor binding was characterized using bio-layer interferometry to measure virus binding to human and avian-like receptor analogues and the pH of fusion was assayed by syncytium formation in virus-infected cells at different pHs. We characterized contemporary H9N2 viruses of the zoonotic G1 lineage, as well as representative viruses of the zoonotic BJ94 lineage. We found that most contemporary H9N2 viruses show a preference for sulphated avian-like receptor analogues. However, the ‘Eastern’ G1 H9N2 viruses displayed a consistent preference in binding to a human-like receptor analogue. We demonstrate that the presence of leucine at position 226 of the HA receptor-binding site correlated poorly with the ability to bind a human-like sialic acid receptor. H9N2 HAs also display variability in their pH of fusion, ranging between pH 5.4 and 5.85 which is similar to that of the first wave of human H1N1pdm09 viruses but lower than the pH of fusion seen in zoonotic H5N1 and H7N9 viruses. Our results suggest possible molecular mechanisms that may underlie the relatively high prevalence of human zoonotic infection by particular H9N2 virus lineages