2,150 research outputs found
Gender-Specific Trajectories of Conduct Problems from Ages 3 to 11
Gender-specific pathways of conduct problems (CP) from toddlerhood have received little attention. Using a nationally representative sample of UK children born in 2000-2001 (6458 boys and 6340 girls), the current study (a) identified subgroups of CP pathways separately for boys and girls from ages 3 to 11 and (b) examined early precursors (pregnancy to 9 months) of these trajectories. Group-based trajectory models identified four distinct trajectories for both boys and girls: each characterized as 'low'; 'early-onset, desisting'; 'early-onset, persistent' and 'school-onset'. This suggests that the taxonomic framework developed to conceptualise childhood-onset CP among males is also applicable to females, though needing some revision to capture heterogeneity identified during early and middle childhood. We also found significant precursors of the different trajectory groups with some variation by gender. Early socioeconomic deprivation was a significant risk factor of the early-onset pathways among both genders, but played no significant role for 'school-onset'. Childhood-onset trajectories of boys, but not girls, were predicted by parenting attitudes and behaviour
Trends in parent- and teacher-rated mental health problems among 10- and 11-year-olds in Great Britain: 1999-2012
BACKGROUND: Previous evidence indicates that mental health problems are becoming more common for adolescents. Less is known about whether these trends have continued and there has been no study to date which has specifically focused on early adolescents over a sufficiently long period. This study examines changes in parent- and teacher-reported mental health problems among 10- and 11-year-olds in 1999, 2004 and 2012 in Great Britain. METHODS: Parent and teacher ratings of the Strengths and Difficulties Questionnaire were used to compare the prevalence of conduct problems, hyperactivity/inattention, emotional problems, peer problems and total difficulties among 10- and 11-year-olds in three nationally representative British samples assessed in 1999 (n = 1904), 2004 (n = 1348) and 2012 (n = 11,397). RESULTS: Teacher reports showed improving trends for boys' and girls' mental health from 1999 to 2012, particularly for externalizing behaviours (i.e. conduct problems and hyperactivity/inattention). Parent reports, on the other hand, identified only one area of sustained improvement between 1999 and 2012, namely hyperactivity/inattention among boys. Although parent reports of girls' mental health indicate improving trends from 1999 to 2004, they also suggest worsening mental health from 2004. CONCLUSIONS: These findings suggest that perceptions of emotional and behavioural problems vary by the gender of the adolescent, the context in which they are observed or by whom they are reported
Developmental Trajectories of Conduct Problems and Cumulative Risk from Early Childhood to Adolescence
Pathways into and out of conduct problems differ by circumstances experienced since infancy. There is a research gap in
understanding how these developmental patterns vary according to the timing and persistence of risk and whether there are
differences across ecological domains. This study examines variations in trajectories of conduct problems between ages 3 to
14 years and associated child, family and socio-economic risk factors from ages 9 months to 14 years, drawing on the UK
Millennium Cohort Study (n = 17,206, 49% female), a nationally representative longitudinal study of children born between
2000/02. Group-based modeling was used to identify four distinct trajectories of conduct problems: low (56%), persistent
high (8%), childhood-limited (23%) and adolescent-onset (13%). All three problem pathways were associated with high
levels of exposure to risk, particularly early socio-economic and persisting child and family risks. However, while for the
persistent and adolescent-onset pathways, exposure to higher levels of family and child risks continued through adolescence,
it receded for the childhood-limited trajectory. The effects of early socio-economic disadvantage persisted for those on the
adolescent-onset trajectory, highlighting the importance of early markers for this later onset group. Maternal smoking in
pregnancy continued to be a significant predictor for all three conduct problem groups, even up to age 14 years. The findings
indicate that different influences and processes may explain diverse pathways of conduct problems. This offers insights into
who and what might be targeted and when might be the most effective developmental window for intervention
Comparative analysis of module-based versus direct methods for reverse-engineering transcriptional regulatory networks
We have compared a recently developed module-based algorithm LeMoNe for
reverse-engineering transcriptional regulatory networks to a mutual information
based direct algorithm CLR, using benchmark expression data and databases of
known transcriptional regulatory interactions for Escherichia coli and
Saccharomyces cerevisiae. A global comparison using recall versus precision
curves hides the topologically distinct nature of the inferred networks and is
not informative about the specific subtasks for which each method is most
suited. Analysis of the degree distributions and a regulator specific
comparison show that CLR is 'regulator-centric', making true predictions for a
higher number of regulators, while LeMoNe is 'target-centric', recovering a
higher number of known targets for fewer regulators, with limited overlap in
the predicted interactions between both methods. Detailed biological examples
in E. coli and S. cerevisiae are used to illustrate these differences and to
prove that each method is able to infer parts of the network where the other
fails. Biological validation of the inferred networks cautions against
over-interpreting recall and precision values computed using incomplete
reference networks.Comment: 13 pages, 1 table, 6 figures + 6 pages supplementary information (1
table, 5 figures
The Generation of Successive Unmarked Mutations and Chromosomal Insertion of Heterologous Genes in Actinobacillus pleuropneumoniae Using Natural Transformation
We have developed a simple method of generating scarless, unmarked mutations in Actinobacillus pleuropneumoniae by exploiting the ability of this bacterium to undergo natural transformation, and with no need to introduce plasmids encoding recombinases or resolvases. This method involves two successive rounds of natural transformation using linear DNA: the first introduces a cassette carrying cat (which allows selection by chloramphenicol) and sacB (which allows counter-selection using sucrose) flanked by sequences to either side of the target gene; the second transformation utilises the flanking sequences ligated directly to each other in order to remove the cat-sacB cassette. In order to ensure efficient uptake of the target DNA during transformation, A. pleuropneumoniae uptake sequences are added into the constructs used in both rounds of transformation. This method can be used to generate multiple successive deletions and can also be used to introduce targeted point mutations or insertions of heterologous genes into the A. pleuropneumoniae chromosome for development of live attenuated vaccine strains. So far, we have applied this method to highly transformable isolates of serovars 8 (MIDG2331), which is the most prevalent in the UK, and 15 (HS143). By screening clinical isolates of other serovars, it should be possible to identify other amenable strains
Cellular development and evolution of the mammalian cerebellum
\ua9 2023, The Author(s).The expansion of the neocortex, a hallmark of mammalian evolution 1,2, was accompanied by an increase in cerebellar neuron numbers 3. However, little is known about the evolution of the cellular programmes underlying the development of the cerebellum in mammals. In this study we generated single-nucleus RNA-sequencing data for around 400,000 cells to trace the development of the cerebellum from early neurogenesis to adulthood in human, mouse and the marsupial opossum. We established a consensus classification of the cellular diversity in the developing mammalian cerebellum and validated it by spatial mapping in the fetal human cerebellum. Our cross-species analyses revealed largely conserved developmental dynamics of cell-type generation, except for Purkinje cells, for which we observed an expansion of early-born subtypes in the human lineage. Global transcriptome profiles, conserved cell-state markers and gene-expression trajectories across neuronal differentiation show that cerebellar cell-type-defining programmes have been overall preserved for at least 160 million years. However, we also identified many orthologous genes that gained or lost expression in cerebellar neural cell types in one of the species or evolved new expression trajectories during neuronal differentiation, indicating widespread gene repurposing at the cell-type level. In sum, our study unveils shared and lineage-specific gene-expression programmes governing the development of cerebellar cells and expands our understanding of mammalian brain evolution
Temperature Modulation of Electric Fields in Biological Matter
Pulsed electric fields (PEF) have become an important minimally invasive surgical technology for various applications including genetic engineering, electrochemotherapy and tissue ablation. This study explores the hypothesis that temperature dependent electrical parameters of tissue can be used to modulate the outcome of PEF protocols, providing a new means for controlling and optimizing this minimally invasive surgical procedure. This study investigates two different applications of cooling temperatures applied during PEF. The first case utilizes an electrode which simultaneously delivers pulsed electric fields and cooling temperatures. The subsequent results demonstrate that changes in electrical properties due to temperature produced by this configuration can substantially magnify and confine the electric fields in the cooled regions while almost eliminating electric fields in surrounding regions. This method can be used to increase precision in the PEF procedure, and eliminate muscle contractions and damage to adjacent tissues. The second configuration considered introduces a third probe that is not electrically active and only applies cooling boundary conditions. This second study demonstrates that in this probe configuration the temperature induced changes in electrical properties of tissue substantially reduce the electric fields in the cooled regions. This novel treatment can potentially be used to protect sensitive tissues from the effect of the PEF. Perhaps the most important conclusion of this investigation is that temperature is a powerful and accessible mechanism to modulate and control electric fields in biological tissues and can therefore be used to optimize and control PEF treatments
Scripts of Sexual Desire and Danger in US and Dutch Teen Girl Magazines: A Cross-National Content Analysis
The aim of this comparative quantitative content analysis was to investigate how US and Dutch teen girl magazines cover sexual desire (i.e., sexual wanting, and pleasure) and sexual danger (i.e., sexual risk, and negative physical/health consequences of sex). Relying on the sexual scripts framework and Hofstede’s cultural dimension of masculinity/femininity, we examined (a) how the coverage varied for boys and girls, (b) how it differed between the United States and the Netherlands, and (c) how gender differences varied by country. The sample comprised 627 sex-related feature stories from all 2006–2008 issues of three US (i.e., Seventeen, CosmoGirl! United States edition, and Teen) and three Dutch teen girl magazines (i.e., Fancy, CosmoGirl! Netherlands edition, and Girlz!). Overall, sexual wanting occurred more frequently in the US magazines than in the Dutch magazines. In the US coverage, boys’ sexual wanting received more attention than girls’ sexual wanting, whereas in the Dutch coverage sexual wanting was depicted equally often for boys and girls. The depiction of sexual pleasure did not vary by gender in either country, but was generally more visible in the Dutch magazines than in the US magazines. Sexual risks and the negative consequences of sex were associated with girls more than with boys, and were primarily depicted in the US magazines rather than in the Dutch magazines
Spatiotemporal epidemic characteristics and risk factor analysis of malaria in Yunnan Province, China
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