Level Crossing Analysis of the Stock Markets

We investigate the average frequency of positive slope $\nu_{\alpha}^{+}$, crossing for the returns of market prices. The method is based on stochastic processes which no scaling feature is explicitly required. Using this method we define new quantity to quantify stage of development and activity of stocks exchange. We compare the Tehran and western stock markets and show that some stocks such as Tehran (TEPIX) and New Zealand (NZX) stocks exchange are emerge, and also TEPIX is a non-active market and financially motivated to absorb capital.Comment: 6 pages and 4 figure

Level Crossing Analysis of Burgers Equation in 1+1 Dimensions

We investigate the average frequency of positive slope $\nu_{\alpha}^{+}$, crossing the velocity field $u(x)- \bar u = \alpha$ in the Burgers equation. The level crossing analysis in the inviscid limit and total number of positive crossing of velocity field before creation of singularities are given. The main goal of this paper is to show that this quantity, $\nu_{\alpha}^{+}$, is a good measure for the fluctuations of velocity fields in the Burgers turbulence.Comment: 5 pages, 3 figure

Effect of age on reproductive performance in female Caspian brown trout (Salmo trutta caspious, Kessler 1877)

Caspian brown trout (Salmo trutta caspius) is one of the economically valuable species in the Caspian Sea.Artificial propagation and production of larvae are the main problems in the early culture of this species.The purpose of this paper is to study the effect of reproductive performance of female broods on opposition reproduction efficiency in Caspian brown trout in the breeding season of 2009. Three groups of female broods (4, 5 and 6 years old) were fertilized with 9 male fish individually. The results showed that,6 year old females have maximum body weight (2150.0 ± 86.6 g), total length (59±2 cm), eggs weight (255.0 ± 30.51 g), egg size (5.37 ± 0.058 mm) and absolute fecundity rate (3060 ± 366.15), while highest average number of ovules in each gram of body weight (16.33 ± 0.58) and relative fecundity (2.08 ± 0.12) belonged to 4 years old females. There were significant differences in mean fertilization rate and survival rate until absorption of yolk sack stage (p<0.05) among the treatments studied. The present study showed that the eggs produced from fertilization of 6 year old female eggs and male mixed milt showed maximum average fertilization percentage (97.5 %), survival rate until eyed stage (92%), hatching percentage (93%), and survival rate until absorption of yolk sack (94.5%)

Relationship among sera lipoprotein abnormalities in healthy individuals with background of diabetic sibling

As the prevalence of lipoprotein abnormalities in adolescents is increasing dramatically, the identification of relevant risk factors is a major public health challenge. The aim of this study was to investigate whether a family history of diabetes could be a risk factor for lipid abnormalities in healthy individuals. This study is a cross-sectional case control study. 179 men and women were studied in two equal-member groups (with diabetic parents' background and without any diabetic sibling). Both groups matched in body mass index (BMI), age and sex. The serum concentration of oxidized-low density lipoprotein (LDL), Apo B100 and insulin were measured by enzyme linked immunosorbant assay technique and TG, Chol, HDL-C, FBS and GTT by enzymatic methods. The LDL-C level was calculated using the Friedewald formula. The results show that there were no significant variation in the amount of plasma FBS, GTT, Cho, TG, LDL and HDL between the two groups, whereas a significant increase was found in the amount of insulin (P = 0.02), Apo B100 (P = 0.001), OX-LDL (P = 0.001) and HOMA-IR (P = 0.03) in the case group as compared to the control group. We conclude that a family history of diabetic parents can lead to lipid parameters abnormalities and CVD risk factor via aggregation of inherited defected genes.Key words: Diabetes, oxidized-low density lipoprotein (LDL), Apo B100, lipoproteins

Multiscaling behavior of atomic-scale friction

The scaling behavior of friction between rough surfaces is a well-known phenomenon. It might be asked whether such a scaling feature also exists for friction at an atomic scale despite the absence of roughness on atomically flat surfaces. Indeed, other types of fluctuations, e.g., thermal and instrumental fluctuations, become appreciable at this length scale and can lead to scaling behavior of the measured atomic-scale friction. We investigate this using the lateral force exerted on the tip of an atomic force microscope (AFM) when the tip is dragged over the clean NaCl (001) surface in ultra-high vacuum at room temperature. Here the focus is on the fluctuations of the lateral force profile rather than its saw-tooth trend; we first eliminate the trend using the singular value decomposition technique and then explore the scaling behavior of the detrended data, which contains only fluctuations, using the multifractal detrended fluctuation analysis. The results demonstrate a scaling behavior for the friction data ranging from 0.2 to 2 nm with the Hurst exponent H = 0.61 +/- 0.02 at a 1 sigma confidence interval. Moreover, the dependence of the generalized Hurst exponent, h(q), on the index variable q confirms the multifractal or multiscaling behavior of the nanofriction data. These results prove that fluctuation of nanofriction empirical data has a multifractal behavior which deviates from white noise