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Siyamak Tahmasebi,1 Saman Mafakheri Bashmaq,2 Mansoureh Karimzadeh,3 Robab Teymouri,4 Mahdi Amini,5 Maryam Sadat M vaghefi,6 M Ali Mazaheri7 1Department of Preschool Education, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran; 2Department of Psychology and Exceptional Children’s Education, Faculty of Psychology and Educational Sciences, Allameh Tabataba’i University, Tehran, Iran; 3Department of Preschool Education, Pediatric Neurorehabilitation Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran; 4Pediatric Neurorehabilitation Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran; 5Addiction Department, Center of Excellence in Psychiatry and Clinical Psychology, School of Behavioral Sciences and Mental Health, Institute of Tehran Psychiatry, Iran University of Medical Sciences, Tehran, Iran; 6Department of Speech Therapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran; 7Department of Clinical Psychology, Shahid Beheshti University, Tehran, Iran Abstract: If mothers work outside the home, some degree of mother–child separation will be experienced and mother–child attachment will be affected. In this study, regarding the attachment styles, sociobehavioral problems in first-grade children with experience of preschool and in those taught by their mothers at-home are compared. A casual-comparative method was used to compare children in the two groups. A total of 320 first-grade children participated in the study. The study measures included a separation anxiety test, an adaptive behavior scale, and a children’s symptom inventory. Data were analyzed using multivariate statistics. Secure attachment in the group with experience of preschool was significantly higher than that in the at-home group. None of the variables, including parents’ education and father’s income, significantly affected attachment style. Neither father’s education, father’s income, or attachment significantly influenced adjustment. Father’s education significantly influenced children’s symptoms. Attachment style and hours of preschool attendance had no effect on Child Symptom Inventory scores. Associations among age at joining preschool, attachment style, and behavioral and adaptive problems in first-grade children were nonlinear and multivariate. By taking into account parents’ awareness, sensitivity, and responsiveness, relative welfare, appropriate quality of child-care centers, and having fewer hours of preschool attendance, the risk factors for early parent–child separation and institutional care can be reduced. Keywords: separation, attachment, adjustment, pathological symptoms, first-grade children

Ranked set sampling is considered as an alternative to simple random sampling and maximum ranked set sampling is a very useful modification of ranked set sampling. In this paper we focused on information content of ranked set sampling and maximum ranked set sampling with unequal samples in terms of past extropy measure and also considered the information content of negative cumulative extropy and its dynamic version based on maximum ranked set sampling and simple random sampling designs. We also compare ranked set sampling data, maximum ranked set sampling data with simple random sampling and with each other. Also here we obtained a new discrimination information measure among simple random sampling data, ranked set sampling data and maximum ranked set sampling data for past extropy measure. [ABSTRACT FROM AUTHOR]

In this paper, we consider a measure of inaccuracy between distributions of the nth record value and parent random variable. We also propose the measure of residual inaccuracy of record values and study characterization results of dynamic cumulative residual inaccuracy measure. We discuss some properties of the proposed measures. [ABSTRACT FROM AUTHOR]

The concept of generalized order statistics (gos) has been introduced as a unified models of ordered random variables. In this paper, we find some properties on concomitants of gos in Morgenstern type bivariate Rayleigh distribution (MTBRD). Recurrence relations between moments of concomitants are also obtained. Some properties of joint distributions for concomitants of gos are presented. Finally, we have derived the best linear unbiased estimator based on concomitants of record values for a parameter involved in MTBRD. [ABSTRACT FROM AUTHOR]

In this article, we introduce a new extension of the generalized linear failure rate (GLFR) distributions. It includes some well-known lifetime distributions such as extension of generalized exponential and GLFR distributions as special sub-models. In addition, it can have a constant, decreasing, increasing, upside-down bathtub (unimodal), and bathtub-shaped hazard rate function (hrf) depending on its parameters. We provide some of its statistical properties such as moments, quantiles, skewness, kurtosis, hrf, and reversible hrf. The maximum likelihood estimation of the parameters is also discussed. At the end, a real dataset is given to illustrate the usefulness of this new distribution in analyzing lifetime data. [ABSTRACT FROM AUTHOR]

This trial was conducted to investigate the effect of arginine (Arg), threonine (Thr) and Arg + Thr administered in ovo on growth performance, digestive organs and intestinal morphology in broiler chickens. On day 14 of incubation, 400 fertile eggs were randomly allotted to five experimental treatments through injection in the amniotic fluid including: (i) control (none injected), (ii) sham (0.5 ml of 0.5% saline), (iii) Arg (35 mg/egg), (iv) Thr (25 mg/egg) and (v) Arg + Thr (35 + 25 mg/egg). After hatching, chicks were given a commercial corn-soya bean diet up to 42 days of age. Daily feed intake ( FI) and body weight ( BW) of chicks were measured during different periods of the trial. Digestive organs were measured for their relative weight and intestinal length on days 11 and 42 of age. Intestinal morphometric traits were evaluated on day 11 of the experiment. Supplementing amino acids affected the performance of broiler chicks as Thr significantly increased FI and BW across starter, grower and finisher periods compared with sham and control (p < 0.05). Furthermore, Arg + Thr injection increased jejunal weight compared with control on day 42 (p < 0.05). Moreover, Arg inclusion led to the greatest villus height and crypt depth among treatments in duodenum (p > 0.05); however, amino acid supplemented groups had lower villus height than control in jejunum (p < 0.05). Negative correlations found between digestive organs related to day 11 of age containing pancreas ( r = −0.484; p = 0.030), duodenal ( r = −0.577; p = 0.007) as well as ileal lengths ( r = −0.471; p = 0.035) and FI of entire period. Otherwise, positive relationships were observed between duodenum ( r = 0.580; p = 0.007) and ileum ( r = 0.582; p = 0.007) weights on day 42 and FI of chickens across the entire phase. In conclusion, Arg and particularly Thr injection into amnion can improve FI and post-hatch growth performance of chickens which may be mediated by the development of digestive organs. [ABSTRACT FROM AUTHOR]

In this article, we introduce the Gompertz power series (GPS) class of distributions which is obtained by compounding Gompertz and power series distributions. This distribution contains several lifetime models such as Gompertz-geometric (GG), Gompertz-Poisson (GP), Gompertz-binomial (GB), and Gompertz-logarithmic (GL) distributions as special cases. Sub-models of the GPS distribution are studied in details. The hazard rate function of the GPS distribution can be increasing, decreasing, and bathtub-shaped. We obtain several properties of the GPS distribution such as its probability density function, and failure rate function, Shannon entropy, mean residual life function, quantiles, and moments. The maximum likelihood estimation procedure via a EM-algorithm is presented, and simulation studies are performed for evaluation of this estimation for complete data, and the MLE of parameters for censored data. At the end, a real example is given. [ABSTRACT FROM PUBLISHER]