Scaling Contributions to the Free Energy in the 1/N Expansion of O(N) Nonlinear Sigma Models in d-Dimensions

Within the 1/N expansion of O(N) nonlinear $\sigma$ models for $d \leq 4$ it is possible to separate consistently the spin-wave and the massive-mode contributions to the scaling part of the free energy near criticality, and to evaluate them to $O(1/N)$. For critical dimensions $d = 2+2/n$ the Abe-Hikami anomaly is recovered, while for $d=2$ the removal of the spin-wave term is justified.Comment: 10 pages, Latex, one figure, submitted to Phys. Lett.

A new approach to dynamic finite-size scaling

In this work we have considered the Taylor series expansion of the dynamic scaling relation of the magnetization with respect to small initial magnetization values in order to study the dynamic scaling behaviour of 2- and 3-dimensional Ising models. We have used the literature values of the critical exponents and of the new dynamic exponent $x_0$ to observe the dynamic finite-size scaling behaviour of the time evolution of the magnetization during early stages of the Monte Carlo simulation. For 3-dimensional Ising Model we have also presented that this method opens the possibility of calculating $z$ and $x_0$ separately. Our results show good agreement with the literature values. Measurements done on lattices with different sizes seem to give very good scaling.Comment: Latex file with six figures. Accepted for publication in IJM

A Study of Dynamic Finite Size Scaling Behavior of the Scaling Functions-Calculation of Dynamic Critical Index of Wolff Algorithm

In this work we have studied the dynamic scaling behavior of two scaling functions and we have shown that scaling functions obey the dynamic finite size scaling rules. Dynamic finite size scaling of scaling functions opens possibilities for a wide range of applications. As an application we have calculated the dynamic critical exponent ($z$) of Wolff's cluster algorithm for 2-, 3- and 4-dimensional Ising models. Configurations with vanishing initial magnetization are chosen in order to avoid complications due to initial magnetization. The observed dynamic finite size scaling behavior during early stages of the Monte Carlo simulation yields $z$ for Wolff's cluster algorithm for 2-, 3- and 4-dimensional Ising models with vanishing values which are consistent with the values obtained from the autocorrelations. Especially, the vanishing dynamic critical exponent we obtained for $d=3$ implies that the Wolff algorithm is more efficient in eliminating critical slowing down in Monte Carlo simulations than previously reported.Comment: Latex, 24 pages, 13 eps figures. Accepted for publication in Computer Physics Communicatio

Coronary artery fistula: Review of 54 cases from single center experience

Background: Demographic and clinical characteristics and angiographic findings of Turkish patients with coronary artery fistula have been investigated in this study and diagnostic tests and treatment methods used in these patients have also been evaluated in detail. Methods: We have examined the cardiac catheterization laboratory database retrospectively between March 2006 and July 2010. Among 49,567 patients, we have noted 60 patients diagnosed as coronary artery fistula. After coronary angiographic images were evaluated by two invasive cardiologists, 54 patients who had clear evidence of vessel of origin and drainage were included in the study. Results: A total of 54 (0.1%) patients with coronary artery fistula were noted. Mean age was 56.7 ± 10.7 years; 42 out of 54 patients had accompanying cardiac disorders. Patients’ complaints were directly associated with the presence of the fistula. Chest pain was the admission symptom in all of the patients with isolated coronary artery fistula. Six patients had coexistent congenital anomalies. Myocardial infarction with ST segment elevation occurred in 11 of the patients. In contrast to the previous reports, the most common artery of origin of the fistula was left anterior descending artery (50.8%) and pulmonary artery was found to be the most frequent region of the fistula drainage by 53.7%. Conclusions: Our findings suggest that large fistulas originating from the proximal segments of coronary arteries may increase the likelihood of atherosclerosis and myocardial infarction even in asymptomatic patients with no evidence of ischemia in noninvasive tests and no dilatation of cardiac chambers, and should therefore be closed

Factors affecting pH increase in tomato paste

Bu çalışmada salçalarda pH yükselmesine etki eden faktörler araştırılmıştır. Bu amaçla 1987 ve 1988 yıllarında Dosan Konserve Fabrikasında, kampanya döneminin muhtelif günlerinde, işlenen domateslerden, üretim hattının çeşitli noktalarından ve elde olunan salçalardan örnekler alınarak fiziksel ve kimyasal yönden araştırılmıştır. Sonuç olarak pH yükselmesi üzerine etkili olan faktörler önem sırasına göre, salça üretiminde kullanılan domateslerin pH'sı, domateslerin işlenmesi sırasında organik asitleri karbon kaynağı olarak kullanabilecek mikroorganizmalar tarafından enfekte edilmesi ve fabrikada yapılan alet ve ekipman temizliğinin etkileri olarak belirlenmiştir.In this research the factors which cause to increase in pH of tomato paste were investigated. With this aim, in 1987 and 1988, during the tomato paste producing period and various days, the samples of tomatoes, the samples from the various points of processing line and the samples of tomato pastes were taken and analyzed pysically and chemically. The samples were.obtained from DOSAN cannery in Yenişehir. As a result, the factors affecting the increase of pH, were found to be variety of tomato, whether the processing line was infected or not and the cleaning fruquency