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This paper is concerned with the problem of statistical hypotheses testing in circular data under weighted sampling. The most powerful test has been obtained when the sampling is subjected to a weight function. Different weight functions are examined for the von Misses distribution. For the same weight function, the critical values and the power of the test can be calculated analytically, and for some, we need to use a numerical method. The simulation study shows that the power of the test increased as the weighted circular distribution is considered in replace of the original circular distribution and the sample data increased. A real-data example has been carried out to show the performance of our method. [ABSTRACT FROM AUTHOR]

Real count data time series often show the phenomenon of the overdispersion. In this paper, we introduce the first-order integer-valued autoregressive process. The univariate marginal distribution is derived from the Delaporte distribution and the innovations are convolution of Poisson with α-fold zero modified geometric distribution, based on binomial thinning operator, for modelling integer-valued time series with overdispersion. Some properties of the model are derived. The methods of Yule-Walker, conditional lea st squares and conditional maximum likelihood are used for estimating of the parameters, and their asymptotic properties are established. The Monte Carlo experiment is conducted to evaluate the performances of these estimators in finite samples. The model is fitted to time series of the weekly number of syphilis cases that are overdispersed count data. [ABSTRACT FROM AUTHOR]

In this article, we propose the gamma kernel estimator for the cumulative distribution functions with nonnegative support. We derive the asymptotic bias and variance of the proposed estimator in both boundary and interior regions and show that it is free of boundary bias. We also obtain the optimal smoothing parameter which minimizes the mean integrated square error (MISE). In addition to consistency, we prove the almost sure convergence of the proposed estimator and show that it follows the same approximate normal distribution as empirical distribution. We presented a simulation study to compare the performance of the proposed estimator with other estimators. We use the proposed estimator to estimate the cumulative probability distribution function of the food expenses for urban households in Iran. [ABSTRACT FROM AUTHOR]

In this article, the comparison between the Fisher information on parameters of the weighted distributions and the parent distributions is done. The most common family of distributions, location–scale family, is considered with the exponential weight functionw(x) =eβxwhere β is a constant. Conditions under which the weighted distributions are more (less) informative than the parent distribution are given. This was done for location, scale, and location–scale families when the scale parameter is considered as a nuisance parameter. Furthermore, using the transformation technique, we show that the results in location–scale family can be generalized to the broader classes of problems that studied the Fisher information of the weighted distributions such as Tzavelas and Economou (2014). As the exponential weight function can include some other weight functions, the obtained results in this article can be generalized for some other weight functions. [ABSTRACT FROM PUBLISHER]

The quadratic discriminant function (QDF) with known parameters has been represented in terms of a weighted sum of independent noncentral chi-square variables. To approximate the density function of the QDF asm-dimensional exponential family, its moments in each order have been calculated. This is done using the recursive formula for the moments via the Stein's identity in the exponential family. We validate the performance of our method using simulation study and compare with other methods in the literature based on the real data. The finding results reveal better estimation of misclassification probabilities, and less computation time with our method. [ABSTRACT FROM AUTHOR]

Gamma-ray bursts (GRBs) have been confidently identified thus far and are prescribed to different physical scenarios, black hole mergers, and collapse of massive stars. The distribution of GRBs duration, which is one of the main characteristics of GRBs, is bimodal. Hence, many authors have used mixtures of distribution models to fit them, which suffers serious estimation problems either from classical or Bayesian approaches. Therefore, in this article we introduced a more flexible class of weighted bimodal distribution, called alpha two-piece skew normal (ATPSN), for modeling GRBs duration data set. Some of the main probabilistic and inferential properties of the distribution are discussed and a simulation study is carried out to illustrate the performance of the MLEs., Competing Interests: No potential conflict of interest was reported by the authors., (© 2020 Informa UK Limited, trading as Taylor & Francis Group.)

Background: There is a strong relationship between physical inactivity and low-grade inflammation and its adverse health outcomes, particularly cardiovascular disease. The level of anti-inflammatory and pro-inflammatory cytokines may be changed by exercise., Objectives: The aim of the present study was to determine the response of certain inflammatory biomarkers to exercise with differences in maximal oxygen consumption (VO2max). These biomarkers were IL-1β, TNF-α, hs-CRP, IL-6, sICAM-1, IL-10, and ratios of TNF-α/IL-10 and IL-6/IL-in circulating peripheral blood (PB)., Materials and Methods: In a semi-experimental study, twenty male students who performed regular football exercise at least three days a week, for two years, were selected by easy sampling at Shahid Chamran university of Iran. Subjects were then randomly assigned to two groups: the protocol of the first group was 30 minutes of running at a speed of 65% of VO2max, and the second group performed six periodic repetitions with three minutes at a speed of 85% of VO2max with a 90-second rest between the repetitions. Blood samples were taken at baseline, immediately after the exercise and at rest. Cytokine levels were quantified by the Sandwich enzyme-linked immunosorbent assay (ELISA) method., Results: The first protocol resulted in a decrease of serum IL-1β to 3.77 ± 0.28 pg/mL at rest, from 4.33 ± 0.28 at baseline and 4.32 ± 0.34 immediately after exercise (P = 0.008 and P = 0.013, respectively). There was also a decrease in the level of sICAM-1 to 260.11±15.64 ng/mL at rest, from 329.58 ± 20.82 at baseline and 302.7 ± 20.49 post exercise (P = 0.013 and P = 0.038, respectively). On the other hand, IL-6 and ratio of IL-6/IL-10 increased to 6.55±0.84 pg/mL and 2.12 ± 0.37 immediately after exercise from baseline (2.73 ± 0.58 and 1.16 ± 0.33) and rest (2.49 ± 0.45 and 0.95 ± 0.19) in the second protocol (P = 0.001 and P = 0.001, respectively for IL-6, and P = 0.047 and P = 0.024, respectively for IL-6/IL-10)., Conclusions: The data of the present study demonstrated that a single bout of exercise with higher-intensity induces a transient increase in some proinflammatory markers, and lower-intensity can reduce these biomarkers.

The aim of the present study is for evaluating the effect of different doses of palmitic acid on spatial learning in T-maze. So, Wister adult male rats were used in five groups and considered 10 rats for each group. The first group as a control group was fed with ordinary diet. Four groups were fed with a diet containing palmitic acid (10%) for 1, 2, 3 and 4 weeks, then rats were trained for spatial learning task by using T-maze at subsequently 9 days based on standard method. The result showed that, spatial learning increased by diet containing palmitic acid 10% for 1, 2 and 3 weeks were significant (p<0.05). However, dietary palmitic acid effect on learning because palmitic acid via palmitoylation modifies numerous important neuronal protein including GAP-43, NMDA receptor, AMPA receptor and these receptors are critical role in learning.

Background: Recent attention has focused on the expression of integrin molecules within the endometrium, and their relation to infertility., Objective: The present prospective study was undertaken to determine whether the endometrium of women with unexplained infertility differs in the expression of very late activation antigens (VLA) from the endometrium of normal fertile women., Methods: Thirty samples of endometrial biopsies from hysterectomies with nonendometrial pathology and 28 endometrial samples by uterine curetting from infertile women in secretary phase at implantation time were collected, stained with three monoclonal antibodies against beta1 integrin subunits including VLA-1 to VLA-3 by immunohistochemical technique and then assessed semiquantitively by microscope. Chi-Square test was used to compare the expression of VLA antigens on epithelial cells, stromal cells, lymphocytes and vessels within endometrial tissues between two groups., Results: The results showed that most VLA integrins were present in fertile and infertile endometrium tissues. There were similarities and differences in the expression of VLA molecules in different compartments. VLA-2, VLA-3 expression on endometrial compartments showed an unaltered pattern of staining during the putative window of implantation in either fertile or infertile women with no significant differences (P-value> 0.5). VLA-1 expression on endometrial compartments changed in fertile and unexplained infertile women, the differences were related to the presence or lack of the molecules on epithelial and stromal cells respectively., Conclusion: Differences may explain causes of unexplained infertility, and suggests that certain integrins may participate in the cascade of molecular events leading to successful implantation and early placental development which requires more investigations.