Although skinfold-derived equations seem to be practical for field application in estimating body fat percentage (BF%) and minimum body mass in Olympic wrestlers, prediction equations applied first need to be cross-validated in Olympic wrestlers to define the best prediction equation. This study aimed to evaluate the most accurate field method to predict BF% in Olympic wrestlers compared to BF% estimated by air displacement plethysmography (ADP). Sixty-one male (body mass 72.4 ± 13.5 kg; height 170.3 ± 7.0 cm; body mass index (BMI) 24.9 ± 3.5 kg.m−2; BF% 8.5 ± 4.9%) and twenty-five female wrestlers (body mass 60.3 ± 9.9 kg; height 161.3 ± 7.1 cm; BMI 23.1 ± 2.5 kg.m−2; BF% 18.7 ± 4.7%) undertook body composition assessments including ADP and nine-site skinfold measurements. Correlations, bias, limits of agreement, and standardized differences between alterations in BF% measured by ADP and other prediction equations were evaluated to validate measures, and multiple regression analyses to develop an Olympic wrestlers-specific prediction formula. The Stewart and Hannan equation for male wrestlers and the Durnin and Womersley equation for female wrestlers provided the most accurate BF% compared to the measured BF% by ADP, with the lowest bias and presented no significant differences between the measured and predicted BF%. A new prediction equation was developed using only abdominal skinfold and sex as variables, predicting 83.2% of the variance. The findings suggest the use of the new wrestler-specific prediction equation proposed in the study as a valid and accurate alternative to ADP to quantify BF% among Olympic wrestlers.

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Bu araştırmada, kitap mühürlerinin günümüz üniversite kütüphanelerindeki kullanımının nasıl olduğu, mühürün nereye basıldığı, mühür tasarımı ve mühür örnekleri incelenerek güncel durumun ortaya konulması amaçlanmıştır. Kütüphane mühürlerinin incelenebilmesi için öncelikli olarak mühürün sözlük anlamı, önemi, tarihçesi konuları genel olarak ele alınmıştır. Yazının devamında da betimsel tarama modeli ile rastgele seçilen kütüphane mühürlerinden örnekler değerlendirilmiştir. Kütüphanelerde kullanılan mühürler konusunda yapılan araştırmaların ve akademik çalışmaların sadece belli bir dönemi kapsaması, çok az sayıda çalışmanın yapılmış olması, literatüre katkı sağlayacak yeni dönem kullanımının ortaya konulması, gelecekte bu konuda yapılacak çalışmalara yol haritası olması hedeflenmiştir. Bu konu hakkında araştırmaların ve yayınların artması yazarlarının en büyük temennisidir.

An important bias can occur when estimating coefficients by maximizing the known partial likelihood function in the Cox regression model with the measurement error covariate. We focus here on Bayesian methods in order to adjust measurement error and aim to propose an adjusting Bayesian method. Constructing simulation studies using Markov Chain Monte Carlo simulation techniques to investigate the performance of models. We compare the proposed method with the existing method that used partial likelihood function, Bayesian Cox regression model ignoring measurement error, the adjusted Bayesian Cox regression model that exists in the literature by a simulation study which consists of different sample sizes, censoring rates, reliability levels, and regression coefficients. Simulation studies indicate that the proposed method outperformed others given some scenarios. A real data set is analyzed for an illustration of the findings.

This study aims to find out optimum weaning age for calves in order to minimize the feeding cost of a farm. Two breeds of calves, i.e. Brown Swiss and Holstein Friesian, were weaned on three different weaning ages, i.e. 30, 45 and 60 days. The calves have been observed from birth to six months. The significant variables on weight gain have been estimated using logarithmic production model. It has been found out that the feeding cost of one kg weight gain for earliest weaning age is about 16% less than for the latest weaning age. It is concluded that shortening weaning age period will reduce the feeding cost and increase the farm income.