Analysis of Non-stationary Data for Heart-Rate Fluctuations in Terms of Drift and Diffusion Coefficients

We describe a method for analyzing the stochasticity in the non-stationary data for the beat-to-beat fluctuations in the heart rates of healthy subjects, as well as those with congestive heart failure. The method analyzes the returns time series of the data as a Markov process, and computes the Markov time scale, i.e., the time scale over which the data are a Markov process. We also construct an effective stochastic continuum equation for the return series. We show that the drift and diffusion coefficients, as well as the amplitude of the returns time series for healthy subjects are distinct from those with CHF. Thus, the method may potentially provide a diagnostic tool for distinguishing healthy subjects from those with congestive heart failure, as it can distinguish small differences between the data for the two classes of subjects in terms of well-defined and physically-motivated quantities.Comment: 6 pages, two columns, 6 figure

Physics of brain dynamics: Fokker-Planck analysis reveals changes in EEG delta-theta interactions in anaesthesia

We use drift and diffusion coefficients to reveal interactions between different oscillatory processes underlying a complex signal and apply the method to EEG delta and theta frequencies in the brain. By analysis of data recorded from rats during anaesthesia, we consider the stability and basins of attraction of fixed points in the phase portrait of the deterministic part of the retrieved stochastic process. We show that different classes of dynamics are associated with deep and light anaesthesia, and we demonstrate that the predominant directionality of the interaction is such that theta drives delt

The effects of group play therapy on self-concept among 7 to 11 year-old children suffering from thalassemia major

Background: Children suffering from thalassemia have higher levels of depression and lower levels of self-concept. Objectives: The aim of this study was to determine if group play therapy could significantly increase self-concept among children with thalassemia major ages 7 to 11 years old in teaching hospitals of Golestan province, Iran, in 2012. Patients and Methods: In this randomized, controlled clinical trial, 60 children with thalassemia major were randomly assigned to intervention (30 children) and control (30 children) groups. The intervention included eight 45 to 60 minute sessions during four weeks, during which the intervention group received group play therapy. The control group received no interventions. Selfconcept was measured three times using the Piers-Harris children’s self-concept scale: before, immediately after, and a month after the intervention. Results: For the intervention group, results showed that the mean self-concept score was significantly higher at the second point in time compared to the baseline (P 0.05). Conclusions: The results showed that group play therapy improves self-concept in children suffering from thalassemia major. © 2016, Iranian Red Crescent Medical Journal

Complications leading to hospitalization due to consumption of anti-TB drugs in patients with tuberculosis in Gorgan, Iran (2007-12)

Background and Objective: Anti tuberculosis drugs therapy is the most effective method for controling the tuberculosis (TB). Early detection and appropriate treatment can prevent the TB-drug resistance. This study was carried out to determine the complications leading to hospitalization due to consumption of anti-TB drugs in patients with tuberculosis. Methods: In this descriptive-analytic study, 1550 records of patients with TB in urban and rural health centers of Gorgan, north of Iran were assessed during 2007-12. Checklist consists of demographic and clinical data for each patient was recorded in a questionare. Results: 44 cases experienced the complications of anti-TB drugs. 27 (61.4%) of cases with complications were women. 77.3% and 22.7% of patients affected with pulmonary and extra pulmonary tuberculosis,respectively. 38.6% of patients were diabetic. The hepatic complication was seen in 37 cases (84.1%). Skin and other complications were seen in 5 and 2 cases, respectively. There was not any relationship between drug complications and other disases. Conclusion: Hepatic damage is the most common complication leading to hospitalization in tuberculosis patients using anti-TB drugs. Keywords: Tuberculosis, Anti-TB drug, Live

Electronic, dielectric and optical properties of two dimensional and bulk ice: a multi-scale simulation study

The intercalated water into nanopores exhibits anomalous properties such as ultralow dielectric constant.~Multi-scale modeling and simulations are used to investigate the dielectric properties of various crystalline two-dimensional ices and bulk ices. Although, the structural properties of two-dimensional (2D-) ices have been extensively studied, much less is known about their electronic and optical properties. First, by using density functional theory (DFT) and density functional perturbation theory (DFPT), we calculate the key electronic, optical and dielectric properties of 2D-ices. Performing DFPT calculations, both the ionic and electronic contributions of the dielectric constant are computed. The in-plane electronic dielectric constant is found to be larger than the out-of-plane dielectric constant for all the studied 2D-ices. The in-plane dielectric constant of the electronic response is found to be isotropic for all the studied ices. Secondly, we determined the dipolar dielectric constant of 2D-ices using molecular dynamics simulations (MDS) at finite temperature. The total out-of-plane dielectric constant is found to be larger than 2 for all the studied 2D-ices. Within the framework of the random-phase approximation (RPA), the absorption energy ranges for 2D-ices are found to be in the ultraviolet spectra. For the comparison purposes, we also elucidate the electronic, dielectric and optical properties of four crystalline ices (ice VIII, ice XI, ice Ic and ice Ih) and bulk water

Aflatoxin contamination in wheat flour samples from Golestan province, Northeast of Iran

Background: Due to the high toxicity of aflatoxin and its effects on public health, determination of aflatoxin level in Wheat flour samples in the Golestan province, north of Iran was investigated. To examine the effect of seasonal changes, summer and winter sampling was performed with standard sampling methods. Methods: A total of 200 flour samples were collected from 25 factories. HPLC method with immunoaffinity chromatography was used to measure aflatoxin types (G2, G1, B2 and B1). Statistical analysis was performed by the Pearson correlation test, One-way ANOVA and multivariate regression analysis. Results: Mean total aflatoxin levels of samples were 0.82 and 1.99 ng/g in summer and winter, respectively. Aflatoxin B1 levels were detected in 3.1%, 7.4% over permissible limits by worldwide regulations in samples collected in summer and winter, respectively. Aflatoxins in winter were higher than summer. The highest frequency of aflatoxin contamination in winter was B2 (98%) and in summer G1 (51%). The relationship between humidity and rate of aflatoxin B1 and total aflatoxin was significant in winter. Results of multivariate regression were showed the strongest relationship with humidity and aflatoxin level. Despite the contamination of flour samples, there was no contamination higher than the standard limit of Iran Standard Institute. But it was significantly higher than similar studies from other regions. Conclusions: Therefore, with regard to negative impacts of aflatoxin on health, aflatoxin contamination should be considered in future programs. Decrease of aflatoxin contamination may be made practical through reducing wheat storage duration and controlling humidity

Marked increase in the incidence rate of esophageal adenocarcinoma in a high-risk area for esophageal cancer

BACKGROUND: Esophageal cancer (EC) is the eighth common cancer worldwide. Esophageal squamous cell carcinoma (ESCC) and adenocarcinoma (EAD) are the most common histologic types of EC. Many recent reports showed an increasing trend in EAD and a decreasing trend in ESCC in many Western countries. Golestan Province in northeastern Iran has been known as a high-risk area for EC. The aim of this study was to describe the time trend of EAD in this area between 2000-2009. METHODS: Data on cancer cases were obtained from Golestan Population-based Cancer Registry. Analysis was done using Joinpoint software. To examine the incidence trends, the annual percent change was calculated. The possibilities of anatomic and histologic misclassification were considered by assessing the trend of ESCC and gastric adenocarcinoma. RESULTS: A total number of 1186 histologically-confirmed EC cases were recruited. The incidence rate of EAD showed a significant increasing trend. There was no significant trend in the incidence of ESCC during the study period. A significant increase in the incidence rate of gastric adenocarcinoma was observed during the period of 2000-2005, followed by a plateau during the period of 2005-2009. CONCLUSIONS: We found a significant increasing trend in the incidence rate of EAD. We find no evidence to support an alternative explanation including anatomic and histologic misclassification. So, the observed rise in the incidence of EAD seems to be real. Therefore, designing and implementation of control programs, including control of preventable risk factors of EAD, should be considered in this high- risk area

Determinants of healthcare utilisation and predictors of outcome in colorectal cancer patients from Northern Iran

We aimed to assess healthcare utilisation (HU), its determinants, as well as its relationship with survival in colorectal cancer (CRC) patients. This study was conducted on incident CRC cases from Northern Iran. Information on HU was collected using a valid questionnaire, considering eight diagnostic and four therapeutic services. The results were categorised as good and poor HU. Multivariate logistic regression analysis was used to assess the relationship between HU and other variables. Cox regression analysis was performed to determine major predictors of survival. In total, 227 new cases of CRC were enrolled. HU could be assessed in 218 subjects (96). Living in rural areas was the strongest variable related to poor HU (adjusted OR, odds ratio=2.65; CI, confidence interval: 1.30-5.40). The median survival time was 40.5months. The 1-, 3- and 5-year survival rates were 71, 52 and 44 respectively. Cox regression analysis showed a significant lower survival rate in patients with poor HU (HR=2.3; CI: 1.46-3.64). HU was an independent predictor of survival in our CRC patients. Patients' place of residence was a significant determinant of HU. Regarding its effects on patients' outcome, HU and its determinants should be considered in designing CRC controlling programmes in our region and similar high-risk populations. © 2016 John Wiley & Sons Ltd