In this work, a new program is presented that, in addition to performing the deconvolution of Thermoluminescence glow curves, allows the user to store multiple deconvolution data. This data is stored ...in an internal database, which allows the fitted parameters to be compared. After these deconvolutions, the program allows the user to summarize the values of the selected parameters. These values can be fitted with some of the available functions to observe the behavior of each parameter for each isolated peak. The program was tested with data from the GLOCANIN project to observe the accuracy of the deconvolution in synthetic and real samples with different number of peaks. Natural quartz grains obtained from sediments and irradiated with different doses were used for the Growth curves. After deconvolution, five peaks were identified, which showed different behaviors; these new data were fitted with different functions using the same program.
•Deconvolution of Thermoluminescence glow curves.•Various glow curves can be analyzed, stored and compared.•After deconvolution, summarizes the behavior of each peak under different conditions.•Specific algorithms have been implemented for processing Thermoluminescence data.•Activation energy values increase with temperature.
•Four nonlinear models were compared to define growth curve in Lohi sheep.•Brody was considered the best fitted model among all the tested models for all categories of Lohi sheep.•Males had higher ...mature weight than females.•All the studied models were able to define age growth relationship in Lohi sheep.
In Pakistan, very few studies have been conducted to define the growth of small ruminants. The objective of present study was to determine the best nonlinear model to describe growth in Lohi sheep. Four nonlinear models (Brody, Gompertz, logistic and von Bertalanffy) with three parameters were used. Data on Lohi sheep was obtained from Small Ruminant Training and Research Centre, Pattoki, Pakistan. The records comprised 10526 age-weight observations on 554 animals (358 females, 196 males; 420 singles and 134 twins) from birth to 18 months of age. Nonlinear models were fitted using easyreg R package in R program to estimate growth curve parameters. The best model was selected on goodness of fit criteria like adjusted coefficient of determination (R2adj), root mean square error (RMSE) and Akaike’s (AIC) and Bayesian information criteria (BIC). Where marginal differences in fit statistic criteria for all models were observed. Brody was the best fitted model to estimate growth curves for all categories of the Lohi sheep. Males had higher mature weight than females. Females had higher rate of maturity and attained mature weight at an earlier age as compared to males. Similarly, differences were also observed in the growth performance of single and twin lambs. Age of dam, year of birth and season of birth also affected growth of animals. The results suggested that Brody model can be used to predict body weight at any age in Lohi sheep.
This study aimed to investigate the developmental change of body growth and gene expression related to fatty acid uptake and oxidation in the yolk sac membrane (YSM) and jejunum during embryogenesis ...in Muscovy ducks. The weights of embryos and yolk sac (YS) (5 embryos per replicate, n = 6) were recorded on embryonic days (E)16, E19, E22, E25, E28, E31, and the day of hatch (DOH). The fat and fatty acid contents in YSM, jejunal histology, and gene expression related to fatty acid metabolism in YSM and jejunum were determined in each sampling time. Among the nonlinear models, the maximum growth is estimated at 2.83 (E22.5), 2.67 (E22.1), and 2.60 (E21.3) g/d using logistic, Gompertz, and Von Bertalanffy models, respectively. The weight of YS, and ether extract-free YS as well as the amounts of fat and fatty acids in YS decreased (P < 0.05) linearly, whereas the villus height, crypt depth, villus height/crypt depth, and musculature thickness in jejunum increased (P < 0.05) linearly during embryogenesis. The mRNA expression of CD36, SLC27A4, and FABP1 related to fatty acid uptake as well as the mRNA and protein expressions of PPARα and CPT1 related to fatty acid oxidation increased in a quadratic manner (P < 0.05) in both YS and jejunum, and the maximum values were achieved during E25 to E28. In conclusion, the maximum growth rate of Muscovy duck embryos was estimated at 2.60 to 2.83 g/d on E21.3 to E23.5, while the accumulations of lipid and fatty acid in YS were decreased in association with the increased absorptive area of morphological structures in jejunum. The gene and protein expression involved in fatty acid metabolism displayed a similar enhancement pattern between YSM and jejunum during E25 to E28, suggesting that fatty acid utilization could be strengthened to meet the energy demand for embryonic development.
Identifying modifiable lifestyle behaviours that facilitate healthy cognitive ageing is of major public interest for the prevention of cognitive decline and dementia. Gardening is associated with ...numerous health benefits, yet few studies have explored the significance of gardening activity in relation to cognitive ageing. Here, longitudinal cognitive data from 467 older adults (aged 79 ± 0.6) of the LBC1921 study were used to examine associations of self-reported gardening at age 79 with lifetime cognitive change (age 11 to 79), and cognitive level (age 79) and slope across later life (age 79 to 90). Cognitive function was assessed at age 11 and 79 using the Moray House Test (MHT), and a battery of psychometric tests assessed cognitive function at ages 79, 83, 87 and 90 (MHT, Raven's Matrices, Verbal Fluency, Logical Memory). Models controlled for individual-level socio-demographic, lifestyle and health covariates including overall physical activity. Higher frequency of gardening was significantly associated with greater lifetime cognitive gain from age 11 to 79 on the MHT (std β = 0.112 P = 0.024), higher general cognitive ability (g) level at age 79 (std β = 0.145, P = 0.001), and higher test-specific scores on the MHT (std β = 0.153, P = 0.001) and Raven's Matrices (std β = 0.102, P = 0.040). Gardening was not associated with subsequent cognitive slopes from age 79 to 90. Overall, these findings suggest that engaging in gardening activities may contribute modestly to healthy cognitive functioning up to the eighth decade of life. Although physical activity was higher in gardeners, it did not explain the gardening and cognitive function relationship.
•We examined whether gardening activity contributes to healthy cognitive ageing in older adults.•Gardening in later life was associated with greater gain in cognitive change from age 11 to 79.•Higher gardening frequency was associated with better cognitive functioning at age 79.•Associations were independent of physical activity, SES, and health covariates.•Gardening was not related to subsequent cognitive decline from age 79 to 90.
Growth curve measurements are fundamental operations in microbiology and molecular biology. Microplate readers have the advantage of high-throughput and automation. This allows for real-time ...monitoring of many bacterial cultures and a decrease in labor and costs. The volume and geometry of a well from a microplate imply that calibration and comparative studies must be performed before switching from one cultivation and growth monitoring system to another. Here, Escherichia coli XL1 Blue was used as a reference strain in order to test the feasibility of using a common, filter-based microplate reader for recording growth curves when performing antibiotic and toxicity testing.
In different theoretical traditions, negative social conditions, attachments, and interactions shape the way individuals view the law and its agents. Although most researchers acknowledge the ...conceptual distinction between different legal attitudes such as legal cynicism and police legitimacy, it remains unclear to what extent these attitudes stem from the same social sources. In the current study, therefore, we evaluate the social and individual factors that influence trajectories of legal cynicism and police legitimacy using a diverse community sample of youths in Zurich, Switzerland. Latent growth curve models were employed to examine patterns of change in legal cynicism and police legitimacy between 13 and 20 years of age. The findings show that legal cynicism and police legitimacy both decline into early adulthood and exhibit high rank‐stability over time. Furthermore, we find that legal cynicism is closely related to individual characteristics that reflect one's inability to recognize or abide by their internal rules. By contrast, police legitimacy is shaped by socialization influences, particularly teacher bonds and police contacts. These results indicate a need to assess the measurement and interpretation of legal cynicism critically in relation to broader legitimacy beliefs and to investigate the shared and distinct sources of these different constructs.
Latent Growth Curve Models (LGCM) have become a standard technique to model change over time. Prediction and explanation of inter-individual differences in change are major goals in lifespan ...research. The major determinants of statistical power to detect individual differences in change are the magnitude of true inter-individual differences in linear change (LGCM slope variance), design precision, alpha level, and sample size. Here, we show that design precision can be expressed as the inverse of
. Effective error is determined by instrument reliability and the temporal arrangement of measurement occasions. However, it also depends on another central LGCM component, the variance of the latent intercept and its covariance with the latent slope. We derive a new reliability index for LGCM slope variance-effective curve reliability (ECR)-by scaling slope variance against effective error. ECR is interpretable as a standardized effect size index. We demonstrate how effective error, ECR, and statistical power for a likelihood ratio test of zero slope variance formally relate to each other and how they function as indices of statistical power. We also provide a computational approach to derive ECR for arbitrary intercept-slope covariance. With practical use cases, we argue for the complementary utility of the proposed indices of a study's sensitivity to detect slope variance when making
longitudinal design decisions or communicating study designs.
Hitting the Road to Adulthood Bleidorn, Wiebke
Personality & social psychology bulletin,
12/2012, Letnik:
38, Številka:
12
Journal Article
Recenzirano
Previous research suggests that normative life transitions have the potential to trigger personality maturation. But what exactly happens during such a transitional stage? The present study examined ...personality trait changes in a sample of 910 German high school students during their transition from school to adult life. Despite the short observation period of three semiannual measurements, growth curve analyses revealed significant mean-level changes in personality traits. These changes occurred primarily in a positive direction, were strongest for the trait of conscientiousness, and most pronounced in those students who were directly confronted with this transitional experience. Bivariate growth curve models indicated that individual differences in personality change were substantially associated with changes in students’ investments into achievement behavior. Supporting socioanalytic perspectives on personality development, these findings can be discussed with respect to process approaches to personality change assuming that consistent behavioral changes might lead to personality change in a bottom-up fashion.
Plate readers can measure the growth curves of many microbial strains in a high-throughput fashion. The hundreds of absorbance readings collected simultaneously for hundreds of samples create ...technical hurdles for data analysis.
Growthcurver summarizes the growth characteristics of microbial growth curve experiments conducted in a plate reader. The data are fitted to a standard form of the logistic equation, and the parameters have clear interpretations on population-level characteristics, like doubling time, carrying capacity, and growth rate.
Growthcurver is an easy-to-use R package available for installation from the Comprehensive R Archive Network (CRAN). The source code is available under the GNU General Public License and can be obtained from Github (Sprouffske K, Growthcurver sourcecode, 2016).
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