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1.
Proc Natl Acad Sci U S A ; 120(47): e2310585120, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37956283

RESUMEN

Human skin is stably colonized by a distinct microbiota that functions together with epidermal cells to maintain a protective physical barrier. Staphylococcus, a prominent genus of the skin microbiota, participates in colonization resistance, tissue repair, and host immune regulation in strain-specific manners. To unlock the potential of engineering skin microbial communities, we aim to characterize the diversity of this genus within the context of the skin environment. We reanalyzed an extant 16S rRNA amplicon dataset obtained from distinct body sites of healthy volunteers, providing a detailed biogeographic depiction of staphylococcal species that colonize our skin. S. epidermidis, S. capitis, and S. hominis were the most abundant staphylococcal species present in all volunteers and were detected at all body sites. Pan-genome analysis of isolates from these three species revealed that the genus-core was dominated by central metabolism genes. Species-restricted-core genes encoded known host colonization functions. The majority (~68%) of genes were detected only in a fraction of isolate genomes, underscoring the immense strain-specific gene diversity. Conspecific genomes grouped into phylogenetic clades, exhibiting body site preference. Each clade was enriched for distinct gene sets that are potentially involved in site tropism. Finally, we conducted gene expression studies of select isolates showing variable growth phenotypes in skin-like medium. In vitro expression revealed extensive intra- and inter-species gene expression variation, substantially expanding the functional diversification within each species. Our study provides an important resource for future ecological and translational studies to examine the role of shared and strain-specific staphylococcal genes within the skin environment.


Asunto(s)
Piel , Staphylococcus , Humanos , Staphylococcus/genética , Filogenia , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Staphylococcus epidermidis/genética , Genómica
2.
BMC Bioinformatics ; 25(1): 67, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347472

RESUMEN

BACKGROUND: Recording and analyzing microbial growth is a routine task in the life sciences. Microplate readers that record dozens to hundreds of growth curves simultaneously are increasingly used for this task raising the demand for their rapid and reliable analysis. RESULTS: Here, we present Dashing Growth Curves, an interactive web application ( http://dashing-growth-curves.ethz.ch/ ) that enables researchers to quickly visualize and analyze growth curves without the requirement for coding knowledge and independent of operating system. Growth curves can be fitted with parametric and non-parametric models or manually. The application extracts maximum growth rates as well as other features such as lag time, length of exponential growth phase and maximum population size among others. Furthermore, Dashing Growth Curves automatically groups replicate samples and generates downloadable summary plots for of all growth parameters. CONCLUSIONS: Dashing Growth Curves is an open-source web application that reduces the time required to analyze microbial growth curves from hours to minutes.


Asunto(s)
Programas Informáticos , Interpretación Estadística de Datos
3.
BMC Bioinformatics ; 25(1): 232, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982382

RESUMEN

BACKGROUND: Characterization of microbial growth is of both fundamental and applied interest. Modern platforms can automate collection of high-throughput microbial growth curves, necessitating the development of computational tools to handle and analyze these data to produce insights. RESULTS: To address this need, here I present a newly-developed R package: gcplyr. gcplyr can flexibly import growth curve data in common tabular formats, and reshapes it under a tidy framework that is flexible and extendable, enabling users to design custom analyses or plot data with popular visualization packages. gcplyr can also incorporate metadata and generate or import experimental designs to merge with data. Finally, gcplyr carries out model-free (non-parametric) analyses. These analyses do not require mathematical assumptions about microbial growth dynamics, and gcplyr is able to extract a broad range of important traits, including growth rate, doubling time, lag time, maximum density and carrying capacity, diauxie, area under the curve, extinction time, and more. CONCLUSIONS: gcplyr makes scripted analyses of growth curve data in R straightforward, streamlines common data wrangling and analysis steps, and easily integrates with common visualization and statistical analyses.


Asunto(s)
Programas Informáticos , Biología Computacional/métodos , Análisis de Datos
4.
Microbiology (Reading) ; 170(2)2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38329407

RESUMEN

tGrowth of microorganisms and interpretation of growth data are core skills required by microbiologists. While science moves forward, it is of paramount importance that essential skills are not lost. The bacterial growth curve and the information that can gleaned from it is of great value to all of microbiology, whether this be a simple growth experiment, comparison of mutant strains or the establishment of conditions for a large-scale multi-omics experiment. Increasingly, the basics of plotting and interpreting growth curves and growth data are being overlooked. This primer article serves as a refresher for microbiologists on the fundamentals of microbial growth kinetics.


Asunto(s)
Microbiología de Alimentos , Cinética
5.
Appl Environ Microbiol ; 90(2): e0141923, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38299817

RESUMEN

In this article, we present a method for designing, executing, and analyzing data from a microbial competition experiment. We use fluorescent reporters to label different competing strains and resolve individual growth curves using a fluorescent spectrophotometer. Our comprehensive data analysis pipeline integrates multiple experiments to simultaneously infer sources of variation, extract selection coefficients, and estimate the genetic contributions to fitness for various synthetic genetic cassettes (SGCs). To demonstrate the method, we employ a synthetic biological system based on Escherichia coli. Strains carry 1 of 10 different plasmids and one of three genomically integrated fluorescent markers. All strains are co-cultured to obtain real-time measurements of optical density (total population density) and fluorescence (sub-population densities). We identify challenges in calibrating between fluorescence and density and of fluorescent proteins maturing at different rates. To resolve these issues, we compare two methods of fluorescence calibration and correct for maturation by measuring in vivo maturation times. We provide evidence of genetic interactions occurring between our SGCs and further show how to use our statistical model to test some hypotheses about microbial growth and the costs of protein expression.IMPORTANCEFluorescently labeled co-cultures are becoming increasingly popular. The approach proposed here offers a high standard for experimental design and data analysis to measure selection coefficients and growth rates in competition. Measuring competitive differences is useful in many laboratory studies, allowing for fitness cost-correction of growth rates and ecological interactions and testing hypotheses in synthetic biology. Using time-resolved growth curves, rather than endpoint measurements, for competition assays allows us to construct a detailed scientific model that can be used to ask questions about fine-grained phenomena, such as bacterial growth dynamics, as well as higher-level phenomena, such as the interactions between synthetic cassette expression.


Asunto(s)
Aptitud Genética , Modelos Teóricos , Espectrofotometría
6.
Glob Chang Biol ; 30(6): e17395, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38923190

RESUMEN

Soil microbes are essential for regulating carbon stocks under climate change. However, the uncertainty surrounding how microbial temperature responses control carbon losses under warming conditions highlights a significant gap in our climate change models. To address this issue, we conducted a fine-scale analysis of soil organic carbon composition under different temperature gradients and characterized the corresponding microbial growth and physiology across various paddy soils spanning 4000 km in China. Our results showed that warming altered the composition of organic matter, resulting in a reduction in carbohydrates of approximately 0.026% to 0.030% from humid subtropical regions to humid continental regions. These changes were attributed to a decrease in the proportion of cold-preferring bacteria, leading to significant soil carbon losses. Our findings suggest that intrinsic microbial temperature sensitivity plays a crucial role in determining the rate of soil organic carbon decomposition, providing insights into the temperature limitations faced by microbial activities and their impact on soil carbon-climate feedback.


Asunto(s)
Carbono , Cambio Climático , Microbiología del Suelo , Suelo , Temperatura , Suelo/química , Carbono/análisis , Carbono/metabolismo , China , Bacterias/metabolismo , Bacterias/crecimiento & desarrollo
7.
Int J Eat Disord ; 57(5): 1245-1252, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38450762

RESUMEN

OBJECTIVE: Appearance focused self-concept (i.e., overvaluing the importance of appearance for self-definition and self-worth) is theorized to predict dietary restraint and binge eating in the short-term (e.g., daily life). Yet, no research has examined whether appearance focused self-concept increases within-persons during a day and if such increases are linked to greater dietary restraint and binge eating for that day. We addressed this gap in knowledge. METHOD: Sixty-three female university students completed four items from the Beliefs About Appearance Scale as a measure of appearance focused self-concept six times per day (9 am, 11 am, 1 pm, 3 pm, 5 pm, and 7 pm) for 14 days. Daily at 9 pm, they completed measures of dietary restraint and binge eating for that day. RESULTS: Analyzing data from 555 days, latent growth curve analyses revealed a small-to-moderate linear increase in appearance focused self-concept from 9 am to 3 pm that plateaued from 3 to 7 pm. A more rapid linear increase in appearance focused self-concept from 9 am to 3 pm was associated with greater binge-eating frequency during that day, but not with dietary restraint. The findings were observed when adjusting for between-day appearance focused self-concept at 9 am, which was positively associated with dietary restraint and binge-eating frequency. DISCUSSION: Findings are discussed in relation to research on appearance focused self-concept as a risk factor for disordered eating. Findings are also discussed in relation to how sociocultural factors may increase appearance focused self-concept over time. Future research should delve into the within-day dynamic interplay between appearance focused self-concept and disordered eating. PUBLIC SIGNIFICANCE: Our study revealed a noteworthy increase in the importance women attach to their appearance over the course of a day, correlating with increased binge eating during that day. Additionally, heightened appearance importance at the onset of a day was associated with more dietary restraint and binge eating during that day. These findings suggest a shorter timescale for the connection between appearance importance and disordered eating than previously understood.


Asunto(s)
Imagen Corporal , Bulimia , Autoimagen , Estudiantes , Humanos , Femenino , Estudiantes/psicología , Universidades , Adulto Joven , Bulimia/psicología , Imagen Corporal/psicología , Adulto , Evaluación Ecológica Momentánea , Adolescente , Conducta Alimentaria/psicología , Trastorno por Atracón/psicología
8.
Qual Life Res ; 33(1): 169-181, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37776401

RESUMEN

PURPOSE: The increased burden of multimorbidity is restricting individuals' ability to live autonomously, leading to a poorer quality of life. This study estimated trajectories of functional limitation and quality of life among middle-aged (ages 50 to 64 years) and older (aged 65 years and older) individuals with and without multimorbidity. We also assessed differences in the relationship between these two trajectories by multimorbidity status and separately for each age cohort. METHODS: Data originated from the Survey of Health, Ageing, and Retirement in Europe (SHARE). In Luxembourg, data were obtained between 2013 and 2020, involving 1,585 respondents ≥ 50 years of age. Multimorbidity was defined as a self-reported diagnosis of two or more out of 16 chronic conditions; functional limitation was assessed by a combined (Instrumental) Activities of Daily Living (ADL/IADLI) scale; and to measure quality of life, we used the Control, Autonomy, Self-Realization, and Pleasure (CASP-12) scale. Latent growth curve modelling techniques were used to conduct the analysis where repeated measures of quality of life and functional limitation were treated as continuous and zero-inflated count variables, respectively. The model was assessed separately in each age cohort, controlling for the baseline covariates, and the estimates from the two cohorts were presented as components of a synthetic cohort covering the life course from the age of 50. RESULTS: Middle-aged and older adults living with multimorbidity experienced poorer quality of life throughout the life course and were at a higher risk of functional limitation than those without multimorbidity. At baseline, functional limitation had a negative impact on quality of life. Furthermore, among middle-aged adults without multimorbidity and older adults with multimorbidity, an increase in the number of functional limitations led to a decline in quality of life. These results imply that the impact of multimorbidity on functional limitation and quality of life may vary across the life course. CONCLUSION: Using novel methodological techniques, this study contributes to a better understanding of the longitudinal relationship between functional limitation and quality of life among individuals with and without multimorbidity and how this relationship changes across the life course. Our findings suggest that lowering the risk of having multimorbidity can decrease functional limitation and increase quality of life.


Asunto(s)
Calidad de Vida , Jubilación , Persona de Mediana Edad , Humanos , Anciano , Calidad de Vida/psicología , Multimorbilidad , Actividades Cotidianas , Envejecimiento , Europa (Continente)/epidemiología , Estudios Longitudinales
9.
Dev Psychopathol ; : 1-17, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38465371

RESUMEN

We took a multilevel developmental contextual approach and characterized trajectories of alcohol misuse from adolescence through early midlife, examined genetic and environmental contributions to individual differences in those trajectories, and identified adolescent and young adult factors associated with change in alcohol misuse. Data were from two longitudinal population-based studies. FinnTwin16 is a study of Finnish twins assessed at 16, 17, 18, 25, and 35 years (N = 5659; 52% female; 32% monozygotic). The National Longitudinal Study of Adolescent to Adult Health (Add Health) is a study of adolescents from the United States, who were assessed at five time points from 1994 to 2018 (N = 18026; 50% female; 64% White, 21% Black, 4% Native American, 7% Asian, 9% Other race/ethnicity). Alcohol misuse was measured as frequency of intoxication in FinnTwin16 and frequency of binge drinking in Add Health. In both samples, trajectories of alcohol misuse were best described by a quadratic growth curve: Alcohol misuse increased across adolescence, peaked in young adulthood, and declined into early midlife. Individual differences in these trajectories were primarily explained by environmental factors. Several adolescent and young adult correlates were related to the course of alcohol misuse, including other substance use, physical and mental health, and parenthood.

10.
J Exp Child Psychol ; 243: 105915, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38555697

RESUMEN

Inhibitory control develops rapidly and nonlinearly, making its accurate assessment challenging. This research investigated the developmental dynamics of accuracy and response latency in inhibitory control assessment of 3- to 6-year-old children in a longitudinal study (N = 431; 212 girls; Mage = 4.86 years, SD = 0.99) and a cross-sectional study (N = 135; 71 girls; Mage = 4.24 years, SD = 0.61). We employed a computerized Stroop task to measure inhibitory control, with fluid intelligence serving as a covariate. A growth curve analysis revealed that children who reached an accuracy threshold of 80% earlier demonstrated faster improvements in response latency. Both the cross-sectional and longitudinal findings demonstrated a positive association between response latency in the inhibitory control task and fluid intelligence, but only when participants had achieved and maintained high accuracy. These results suggest that researchers should consider response latency as an indicator of inhibitory control only in children who manage to respond accurately in an inhibitory control task.


Asunto(s)
Desarrollo Infantil , Inhibición Psicológica , Inteligencia , Tiempo de Reacción , Test de Stroop , Humanos , Femenino , Masculino , Niño , Estudios Transversales , Estudios Longitudinales , Desarrollo Infantil/fisiología , Preescolar , Inteligencia/fisiología , Función Ejecutiva/fisiología
11.
Artículo en Inglés | MEDLINE | ID: mdl-38970672

RESUMEN

PURPOSE: Despite the concerns about older adults' overall quality of life during the COVID-19 pandemic, they often demonstrated better resilience, adaptability, and subjective well-being (SWB) than younger individuals. However, longer-term trends remain unclear. This study aims to describe older adults' trajectories in SWB dimensions before, during, and after the pandemic spanning 2017-2022. METHODS: This study used piecewise growth curve analysis on a subsample of the Swiss Household Panel to investigate the population-average (n individuals = 3086; n = observations = 13,780) trajectories of SWB dimensions and stress among adults aged 65 and older between 2017 and 2022. We also tested whether these trajectories differed by age, gender, and household income. RESULTS: Life satisfaction and positive affect remained stable among older people during the pandemic (2019-2021) but declined after. Negative affect increased during the pandemic and decreased afterward, while stress levels increased slightly before and significantly after the pandemic. The trajectories did not differ by gender or household income, but the oldest-old (> 75-year-old) had a more significant decline in positive affect and life satisfaction pre-pandemic (2017-2019) and stress during the pandemic (2020-2021). CONCLUSION: Research shows that older adults possess adaptation skills and emotional competencies, which enable them to navigate pandemic challenges. However, we show that the post-pandemic era presents more substantial challenges for this older population, who perhaps face more difficulties adapting to the new uncertain post-pandemic world. Further research needs to examine if these findings replicate in other contexts, for instance, where pandemic containment measures have been more stringent.

12.
J Pers ; 92(2): 530-547, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37208805

RESUMEN

INTRODUCTION: Humanistic psychologists have conceptualized a tendency among humans to experience continual open-ended psychological growth. This study aims to measure the rate at which one grows psychologically using a novel growth curve modeling approach that addresses previous limitations. We also examine the effects of nine potential contributors to growth identified from the literature. METHOD: Throughout the freshman year, 556 college students responded six times. Increments of growth were added up to create cumulative growth, which was then fit to a growth curve model to produce an estimate of the growth rate. The growth rate was then regressed on the Time 1 predictors to examine their unique effects. RESULTS: Models fit well. Five predictors significantly predicted the growth rate after controlling for the average of other predictors. When all predictors were entered simultaneously, three predictors (hope, meaning, and personal growth initiative) showed significant unique effects. The growth rate predicted well-being and satisfaction at Time 6. CONCLUSION: We successfully measured the rate of psychological growth and examined its antecedents. Follow-up analyses suggested that the predictors not showing unique effects may indirectly predict growth rates via the proximal role of the three significant predictors, an idea that awaits future corroboration using within-individual designs.


Asunto(s)
Crecimiento Psicológico , Estudiantes , Humanos , Estudios Longitudinales
13.
J Pers ; 92(1): 130-146, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37041673

RESUMEN

OBJECTIVE: Personality changes across the life span. Life events, such as marriage, becoming a parent, and retirement, have been proposed as facilitating personality growth via the adoption of novel social roles. However, empirical evidence linking life events with personality development is sparse. Most studies have relied on few assessments separated by long time intervals and have focused on a single life event. In contrast, the content of life is composed of small, recurrent experiences (e.g., getting sick or practicing a hobby), with relatively few major events (e.g., childbirth). Small, frequently experienced life events may play an important and overlooked role in personality development. METHOD: The present study examined the extent to which 25 major and minor life events alter the trajectory of personality development in a large, frequently assessed sample (Nsample = 4904, Nassessments = 47,814, median retest interval = 35 days). RESULTS: Using a flexible analytic strategy to accommodate the repeated occurrence of life events, we found that the trajectory of personality development shifted in response to a single occurrence of some major life events (e.g., divorce), and recurrent, "minor" life experiences (e.g., one's partner doing something special). CONCLUSION: Both stark role changes and frequently reinforced minor experiences can lead to personality change.


Asunto(s)
Desarrollo de la Personalidad , Personalidad , Humanos , Estudios Longitudinales , Personalidad/fisiología , Trastornos de la Personalidad , Acontecimientos que Cambian la Vida
14.
J Res Adolesc ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717855

RESUMEN

Although overparenting is a growing phenomenon across the globe, there is a severe lack of longitudinal studies examining the trajectory of overparenting and its effects on early adolescent development, particularly in non-Western contexts. The study collected three waves of longitudinal data from 1328 early Chinese adolescents in Hong Kong with an interval of 1 year to examine the stability and change of perceived paternal and maternal overparenting and their effects on adolescent psychological wellbeing. The results indicated that perceived paternal and maternal overparenting declined over time. Besides, adolescents reported lower anxiety and depressive symptoms when they perceived a steep decline in maternal overparenting. Adolescent anxiety at earlier time points also predicted a steeper decline in paternal and maternal overparenting trajectories respectively. Furthermore, we identified gender differences in the initial level of paternal overparenting and the trajectory of maternal overparenting, as well as the effects of rates of change of maternal overparenting on adolescent anxiety and depressive symptoms. The findings give support for self-determination theory and the separation-individuation model, suggesting that changes of overparenting may hinder adolescents' desires for autonomy and self-direction, which may increase their psychological morbidity. The study contributes to theoretical development of contemporary Chinese socialization models and provides useful pointers for future studies of overparenting.

15.
J Biosoc Sci ; : 1-16, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38646721

RESUMEN

Existing research on human growth in Mexico is regionally focused, creating a gap in the understanding of growth patterns of children and adolescents at national level and regional variation. The objective of the present study was to characterize the height growth curve of the Mexican population by geographic area and to cluster the states of the Mexican Republic according to their somatic maturation characteristics, based on a national representative sample of boys. Data on age, height, socioeconomic level, and geographic area of 18,219 boys were obtained from the National Health and Nutrition Survey 2012 (ENSANUT) and ENSANUT 2018, carried out in 32 Mexican states. Both surveys had representative samples. Preece-Baines 1 model was applied to fit height growth curves. Biological parameters were estimated; principal component analysis and cluster analysis were performed to group Mexican states based on these biological parameters. The estimated age at peak height velocity (PHV) was 12.3 years in the sample. Significant regional differences in the timing and tempo of PHV among Mexican boys were observed. Boys in the northern region experienced PHV at an earlier age and had a shorter duration of growth compared with boys in the central and southern regions. Boys in the central region had a longer duration of growth and a later age of PHV compared with the boys in the southern region. The cluster that included the southern states of the country showed estimated lower adult height and earlier somatic maturation. A lower height was found in the low and low-middle socioeconomic levels compared with the medium-high and high socioeconomic levels. Future research in Mexico should focus on longitudinal studies to analyse the timing and tempo of growth and maturation, considering the impacts of environmental and genetic factors. Public health strategies should account for geographic variations.

16.
J Adolesc ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39075629

RESUMEN

OBJECTIVE: Previous research linked problematic mobile social media use to non-suicidal self-injury (NSSI). However, little research explored the underlying mechanism. Drawing on the social displacement hypothesis, which suggests that excessive social media use may disrupt offline social interactions, leading to negative emotional experiences, the study employs a longitudinal design to explore the relationship between problematic mobile social media use and NSSI, with a specific emphasis on the mediating role of self-disgust. METHODS: A total of 1,684 Chinese adolescents (52.3% females; Mage = 14.59 years, SDage = 1.27) completed self-report questionnaires regarding problematic mobile social media use, self-disgust, and NSSI. The assessment was conducted in three waves, 6 months apart. RESULTS: Using latent growth curve and structural equation modeling, our study observed a consistent linear decline in NSSI levels over time. Higher initial NSSI levels correlated with a slower reduction. Problematic mobile social media use positively influenced the initial level of NSSI. Additionally, self-disgust played a mediating role in the relationship between problematic mobile social media use and NSSI. CONCLUSIONS: The study underscores the importance of understanding the emotional experiences behind social media use, beyond mere usage duration. By revealing the mediating role of self-disgust, it provides new insights into the complex interplay between problematic mobile social media use and adolescent NSSI.

17.
J Anim Breed Genet ; 141(4): 425-439, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38288883

RESUMEN

The objective of this study was to estimate genetic effects on parameters of the Brody and Richards growth curves using body weight records from birth to 12 months of age on 2287 Muzaffarnagari lamb for a period of 29 years (1976-2004). Estimated growth curve parameters were analysed using six univariate animal models, and genetic correlations among and between the parameters of each function and between parameters of the functions and observed birth and yearling weights were estimated using bivariate analyses. Significant environmental factors including birth year, sex, season, birth status and dam parity were included as fixed effects in all models. Likelihood ratio tests indicated that maternal genetic effects were significant only for birth weight (BW) and degree of maturity at birth (u0) for the Brody and Richards functions. For these traits, direct heritabilities were similar (0.21, 0.19 and 0.17, respectively), but the estimated maternal heritability for BW (0.18) was twice that of u0 for both functions. Heritabilites for yearling weight and asymptotic final body weights for the Brody and Richards functions were 0.28, 0.17 and 0.21, respectively. The remaining growth curve parameters were lowly heritable, ranging from zero for the predicted degree of maturity at the age of maximum growth rate for the Richards function to 0.08 for the maturing rate parameter of the Brody function. Genetic correlations between corresponding parameters for different growth functions exceeded 0.88. Our results showed that the Brody and Richards functions had similar genetic architecture, but the Richards function had no apparent advantages over the more easily interpreted Brody function. Failure to identify maternal genetic effects on maturing rate parameters suggested that both functions failed to identify potentially important maternal genetic effects. Therefore, there is no usefulness of estimated growth curve parameters in selection compared to the simple multi-trait genetic evaluations of individual body weights.


Asunto(s)
Peso Corporal , Animales , Peso Corporal/genética , Femenino , Masculino , Ovinos/genética , Ovinos/crecimiento & desarrollo , India , Peso al Nacer/genética , Cruzamiento
18.
J Therm Biol ; 121: 103832, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537345

RESUMEN

This study aims to explore the effects of climate on the performance and offspring development of aged Merino sheep relocated from an arid, cold environment with harsh grazing conditions to a dry, temperate-cold valley with irrigated pasture production. We utilized time series data from merino sheep in a dry temperate-cold climate in southern Argentina to characterize their growth curves, assess the impact of climate on performance, and compare offspring growth with maternal growth. Our approach involved developing a dynamic model, a non-autonomous differential equation growth curve based on the widely used Brody model. The model considered variables such as local temperature, age, sex, origin, and pregnancy status to determine the optimal combination of parameters for sheep growth in our dataset. The results have shown that moving the old sheep from the steppe to the valley resulted in an increase of an average of 1 kg in weight, but their offspring had an asymptotic weight of 65 kg, 17 kg more than their mothers. The optimum temperature for the growth rate was 15.7+/-0.56 C and 8.7+/-6.3C for the asymptotic weight.


Asunto(s)
Temperatura , Animales , Femenino , Masculino , Ovinos/crecimiento & desarrollo , Ovinos/fisiología , Argentina , Embarazo , Clima , Modelos Biológicos , Peso Corporal
19.
Fam Process ; 63(1): 228-242, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36786006

RESUMEN

After the rapid increase of the American divorce rate in the late 20th century, one of the most conspicuous efforts of the marriage movement in the 1990s that was used to increase marital stability was the legislation of the covenant marriage license, a more restricted marriage license issued in three different states of the U.S. To investigate the marital life of newlywed covenant versus standard couples, a large-scale 5-year couple study was conducted between 1998 and 2003 in Louisiana. The present study uses this large-sample, multiple-wave, multiple-group dyadic dataset to examine differences in co-development and divorce rates in 297 covenant and 380 standard mixed-sex couples using a multiple group growth curve modeling and survival analysis. We examined differences in marital trajectories between covenant and standard couples as well as between husbands and wives in each marital group. The results show (1) that the couples in both groups experienced, on average, declines in marital satisfaction, and such a decline was slower in covenant husbands than their wives as well as those in standard marriages, and (2) that co-development in marital satisfaction was more prominent in standard marriages than in covenant marriages, meaning standard couple's marital satisfaction declined at a more similar rate than that of covenant couples. We provide possible explanations and discuss practical implications.


Asunto(s)
Matrimonio , Satisfacción Personal , Humanos , Esposos
20.
J Youth Adolesc ; 53(3): 685-700, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38015356

RESUMEN

Ethnic-racial pride (positive feelings about one's ethnic-racial group) is critical to healthy identity development across the lifespan. Research on ethnic-racial pride development among Latinx populations has focused exclusively on youth, without regard to pride development amongst parents and relations between pride within family units. Using multivariate Latent Growth Curve Modelling among 674 Mexican-origin youth and their parents (673 mothers; 437 fathers), the trajectory of youth's pride from 5th grade through emerging adulthood (14 years/12 waves of data) as well as relations with parental pride trajectories were examined. Respondents' pride generally decreased from waves 1 to 7 (~age 11-17 in youth) and increased after wave 7. Youth's and mothers' trajectories were unrelated, but complex associations emerged between youth's and fathers' trajectories. This study supports the dynamic nature of ethnic-racial pride across distinct life stages and underscores the complex interplay of youth and parental pride trajectories, emphasizing the pivotal role parents may play in co-shaping identity development alongside their children.


Asunto(s)
Madres , Padres , Femenino , Adolescente , Humanos , Niño , Adulto , Masculino , Emociones , Grupos Raciales , Padre
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