Mehmet Ziya Firat

The reliability and validity of the Turkish version of the Wijma Delivery Expectancy/Experience Questionnaire (W-DEQ) with pregnant women.

This methodological study was planned to translate the Wijma Delivery Expectancy/Experience Questionnaire (W-DEQ) into Turkish and to investigate its reliability for both nulliparous and parous women in Turkish population. A total of 660 healthy women with normal pregnancies at gestational ages of between 28 and 40 weeks were recruited. The internal consistency reliability (Cronbachs α) was used for determining the reliability of the W-DEQ. Construct validity was also determined utilizing the known-groups method. In this study, independent sample t-tests were used to compare the nulliparous and parous groups differing in known fear status. In order to test the construct of the W-DEQ, Beck Anxiety Inventory, Depression Anxiety and Stress Scale and Brief Measure of Worry Severity scales were chosen as these scales are expected to correlate with the W-DEQ. Analysis of the construct validity of the W-DEQ version A using Pearsons correlation coefficients was performed for both nulliparous and parous women separately. All the scales in both groups showed a statistically significant correlation with the W-DEQ. The alpha coefficient (0.89) is well above the 0.70 criterion for internal consistency reliability. Turkish form of Wijma Delivery Expectancy/Experience Questionnaire Version A was fixed as reliable and valid means to measure the level of fear of childbirth among Turkish pregnants.

Confirmatory and exploratory factor analysis of the caregiver quality of life index-cancer with Turkish samples

PurposeThe purpose of this study was to test the reliability and validity of the Turkish version of the CQOLC in Turkey.MethodsThe 35-item English version of the CQOLC was translated into Turkish following the standard translation methodology. The questionnaire was administered to 237 caregivers of patients with cancer. Confirmatory and exploratory factor analyses (CFA and EFA) were carried out using principal component analysis with varimax rotation and Kaiser Normalization to test its construct validity. We used Cronbach’s alpha to examine the CQOLC’s reliability (internal consistency).ResultsThe CFA did not confirm the original factor model. The EFA yielded a 25-item measure with a four-factor solution with different labels for three of the four original scales (shown in parentheses): Psychological Distress (Burden), Disruption in Daily Life (Disruptiveness), Caregiving Responsibility (Positive Adaptation), and Financial Concerns (Financial Concerns). Cronbach’s alpha for the total scale was 0.88 and subscale alpha coefficients ranged from 0.73 to 0.83.ConclusionsThe results indicate some differences in the factor structures of the CQOLC scale between Turkish and American samples but provided preliminary support for the Turkish version of the CQOLC as a reliable and valid measure of the quality of life of Turkish cancer caregivers.

Univariate analysis of test day milk yields of British Holstein‐Friesian heifers using Gibbs sampling

Estimates of posterior distributions of genetic and phenotypic parameters and functions of them for individual test day milk yield are obtained for 28 873 British Holstein‐Friesian heifers, the progeny of 40 proven and 649 unproven sires, using restricted maximum likelihood (REML) and Gibbs sampling methods with a univariate sire model. Results from the two methods are then compared. It is found that the posterior expectations and REML estimates of the parameters are fairly similar. The marginal posterior expectation and REML estimate of heritability for lactation milk yield are 0.49 and 0.50, respectively. Heritability estimates for individual test day records range from 0.27 to 0.40, whilst the posterior expectations are between 0.28 and 0.42. Generally, heritabilities for test day records were lowest at the start and highest in the second half of the lactation. Gibbs sampling requires substantially more computing than REML estimation, but provides a more informative analysis.

Surface wetting and its effect on body and surface temperatures of domestic laying hens at different thermal conditions.

This study investigated the efficacy of surface wetting at different thermal conditions on core body, head, and dorsal surface temperatures in laying hens. Hens were sprinkled on the head and dorsal surface by releasing a sprinkling dosage of 10 mL.bird(-1). The first measurement was taken presprinkling, and the second was taken immediately postsprinkling and then repeated every 5 min for 20 min. The cooling water needs for intermittent partial surface wetting to relieve acute heat stress in the laying hens were quantified for 48 domestic laying hens under 4 experimental thermal conditions. The hens were kept at 4 thermal conditions at average dry-bulb temperatures of 31.30 +/- 0.03, 33.20 +/- 0.08, 36.01 +/- 0.12, and 40.24 +/- 0.08 degrees C; RH of 67.68 +/- 0.37, 51.78 +/- 1.98, 24.59 +/- 0.90, and 16.12 +/- 1.55%; and air velocities of 0.09 +/- 0.00, 0.07 +/- 0.00, 0.08 +/- 0.00, and 0.09 +/- 0.00 m.s(-1), respectively. The differences in core body, head, and dorsal surface temperatures among the 4 thermal groups were 0.15, 0.18, 0.23, and 0.22 degrees C for core body temperature; 1.63, 1.44, 2.51, and 0.97 degrees C for core head temperature; and 1.23, 1.37, 1.41, and 0.64 degrees C for core dorsal temperature at thermal conditions 1, 2, 3, and 4, respectively. There were significant differences in core body, head, and dorsal surface temperatures among the 4 thermal condition groups. It was concluded that the spraying interval was directly proportional to the product of the vapor pressure deficit and the thermal resistance of convective mass transfer of the wetted hens, because there were no significant differences in the air velocity among the 4 thermal condition groups and the air velocity was very low.

An investigation into the effects of clinical mastitis on milk yield in dairy cows

Abstract Milk and disease records were used from 1275 lactations of British Friesian cows, belonging to Sonning farm of Reading University, resulting from calvings that occurred between 1984 and 1989. Eight hundred and forty pairs of successive lactations were available from the total lactation recorded. These were used to consider the relationship between the occurrence of clinical mastitis and changes in milk yield, and to develop a statistical technique that enables the estimation of changes between successive lactations associated with clinical mastitis. The average incidence of clinical mastitis was found to be 35.8% per year. A significant correlation between successive lactations of the same animal was observed for total milk yield. Pairs of successive lactations without clinical mastitis were then compared by a least squares multiple linear regression analysis with pairs in which disease occurred in the current lactation but not in the preceding one. Cows that had clinical mastitis in the current lactation yielded significantly less milk: 231 kg per lactation less than those without mastitis in the current lactation. This mean reduction in the total milk yield applied for all cows irrespective of yielding ability.

Genetic parameter estimates of growth curve and reproduction traits in Japanese quail

The goal of selection studies in broilers is to obtain genetically superior chicks in terms of major economic traits, which are mainly growth rate, meat yield, and feed conversion ratio. Multiple selection schedules for growth and reproduction are used in selection programs within commercial broiler dam lines. Modern genetic improvement methods have not been applied in experimental quail lines. The current research was conducted to estimate heritabilities and genetic correlations for growth and reproduction traits in a Japanese quail flock. The Gompertz equation was used to determine growth curve parameters. The Gibbs sampling under a multi-trait animal model was applied to estimate the heritabilities and genetic correlations for these traits. A total of 948 quail were used with complete pedigree information to estimate the genetic parameters. Heritability estimates of BW, absolute and relative growth rates at 5 wk of age (AGR and RGR), β0 and β2 parameters, and age at point of inflection (IPT) of Gompertz growth curve, total egg number (EN) from the day of first lay to 24 wk of age were moderate to high, with values ranging from 0.25 to 0.40. A low heritability (0.07) for fertility (FR) and a strong genetic correlation (0.83) between FR and EN were estimated in our study. Body weight exhibited negative genetic correlation with EN, FR, RGR, and IPT. This genetic antagonism among the mentioned traits may be overcome using modern poultry breeding methods such as selection using multi-trait best linear unbiased prediction and crossbreeding.

Which is the dominant factor for perception of rheumatic pain: meteorology or psychology?

It is believed that there is an association between the weather and rheumatic symptoms. We aimed to investigate what kind of association is present and what are the factors which determine the nature of this association. Fifty-six subjects with rheumatic disease (31 RA, 15 SpA, 10 OA) who live in Antalya were followed between December 2005 and July 2006. Patients were asked to fill diaries which contain questions regarding the symptoms of their rheumatic diseases everyday. In every monthly visit, disease activity measurement, laboratory assessment and Beck depression inventory assessment were recorded. The symptomatic and psychological measurements were matched with the meteorological data of Antalya Regional Directorate of Meteorological Service of Turkish State. Correlation of symptoms with weather variables was investigated. Contributory effect of weather and of psychologic factors on symptom scores were evaluated by stepwise multiple regression analysis. Eighty-four percent of subjects belive in an association between weather and rheumatism, while 57% claimed to have ability to forecast weather. The maximum correlation coefficient between weather and arthritis symptoms was −0.451 and the maximum contribution of weather on symptoms was 17.1%. Arthritis symptoms were significantly contributed by Beck depression score. The belief about presence of weather–arthritis association was found to be stronger than its statistical power. Our results did not prove or rule out the presence of weather–rheumatism association. As long as the scientific attempts result in failure, the intuitive support in favour of the presence of weather–arthritis association will go on forever.

An Upper Bound for Accuracy of Prediction Using GBLUP

This study aims at characterizing the asymptotic behavior of genomic prediction R2 as the size of the reference population increases for common or rare QTL alleles through simulations. Haplotypes derived from whole-genome sequence of 85 Caucasian individuals from the 1,000 Genomes Project were used to simulate random mating in a population of 10,000 individuals for at least 100 generations to create the LD structure in humans for a large number of individuals. To reduce computational demands, only SNPs within a 0.1M region of each of the first 5 chromosomes were used in simulations, and therefore, the total genome length simulated was 0.5M. When the genome length is 30M, to get the same genomic prediction R2 as with a 0.5M genome would require a reference population 60 fold larger. Three scenarios were considered varying in minor allele frequency distributions of markers and QTL, for h2 = 0.8 resembling height in humans. Total number of markers was 4,200 and QTL were 70 for each scenario. In this study, we considered the prediction accuracy in terms of an estimability problem, and thereby provided an upper bound for reliability of prediction, and thus, for prediction R2. Genomic prediction methods GBLUP, BayesB and BayesC were compared. Our results imply that for human height variable selection methods BayesB and BayesC applied to a 30M genome have no advantage over GBLUP when the size of reference population was small (<6,000 individuals), but are superior as more individuals are included in the reference population. All methods become asymptotically equivalent in terms of prediction R2, which approaches genomic heritability when the size of the reference population reaches 480,000 individuals.

Nonlinear mixed effects modeling of growth in Japanese quail

The aim of this study was to examine the use of a nonlinear mixed modeling approach to growth studies of Japanese quail. Weekly BW measurements of 89 female and 89 male quail were used in the study. A well-known logistic growth function was used in the analysis. The function was expanded to include a sex effect and random bird effects in β0 and β2 parameters. Analyses were performed via SAS 9.2 software. The performance of 3 models, a fixed effects model (model 1) including only sex effect, a mixed effects model (model 2) including sex effect in β0 and β2 parameters and random bird effect in β0, and a mixed effects model (model 3) including sex and random bird effects in β0 and β2 parameters, was compared. The minimized value of -2 times the log-likelihood, Akaike information criterion, corrected version of Akaike information criterion, and Schwarz information criterion values indicated a better fit of model 3 relative to other competitive models. Furthermore, the error variance reduction in model 2 and model 3 compared with model 1 was 60 and 65%, respectively, indicating the better fit of the mixed effect models. Significant differences between sexes were also determined in β0 and β2 parameters, in which the males, on average, had lower β0 and higher β2 parameters than females.

Menstrual Attitude Questionnaire: confirmatory and exploratory factor analysis with Turkish samples

AIM This study is a report of an investigation of the psychometric properties of the Turkish version of the Menstrual Attitude Questionnaire. BACKGROUND Cultural, social and family environments influence womens beliefs about and attitudes towards menstruation. Awareness of these beliefs and/or attitudes and their cultural origins is necessary to understand women and their reactions to menstruation when offering health care. Although the Menstrual Attitude Questionnaire has been used in several studies, the psychometric properties of the Turkish version have not been investigated. METHODS Confirmatory factor analyses were carried out with two different samples - high school (n = 650) and undergraduate university students (n = 569) - in Turkey in the spring semester of 2006. Exploratory factor analyses were then used to modify the factor structure. RESULTS Confirmatory factor analysis did not confirm the factor model reported in the United States of America. However, compared with British and Indian samples, Turkish attitudes showed better fit than both British and Indian samples with comparative fit index values of 0.776 and 0.797 for the high school and university samples respectively. Finally, exploratory factor analysis yielded a 28-item measure for the high school sample and 31-item measure for the university sample, with a 5-factor solution. Reliability estimates of both scales were satisfactory, being 0.73 for the high school and 0.79 for the university sample. CONCLUSION The modified 5-factor Menstrual Attitude Questionnaire could be a useful tool for assessing menstrual attitudes among Turkish high school and university students. The overall score permits comparison with results from earlier studies using the original instrument.