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961.
Background
Although research into the continuity and change of personality traits during a lifespan has been fairly extensive, little research has been conducted on childhood predictors of adult personality.Purpose
We aimed to investigate the association between infant socioeconomic status (SES), and Eysenck personality traits in adulthood. An additional aim was to investigate whether intelligence and education may mediate this association.Methods
SES of 9125 children in the Copenhagen Perinatal Cohort was recorded at a 1-year examination. A subsample of this cohort, comprising 1182 individuals, participated in a follow-up at 20–34 years and was administered the Eysenck Personality Questionnaire (EPQ) which includes measures of neuroticism, extraversion, psychoticism and the so-called lie-scale. Associations of SES with each of the four personality traits were analysed by bivariate and partial correlations, and the mediating effects of intelligence and years of education were analysed.Results
Higher SES in infancy was associated with lower neuroticism (r = −0.06; p = 0.05), lower lie-scale scores (r = −0.11; p = 0.0002), and higher psychoticism (r = 0.09; p = 0.003). However, analyses of mediation revealed no direct effect of infant SES on any of the adult personality traits, but only indirect effects mediated by intelligence and years of education, with intelligence being the main mediating factor.Conclusion
Only weak associations were observed between infant SES and personality in young adulthood, and the observed associations were mediated by adult intelligence and educational level. Thus, factors associated with infant SES or family background appears to have weak direct effects on personality development. 相似文献962.
963.
Thomas E. Ichim Fabio Solano Rosalia De Necochea Campion Erik J. Woods Constantin A. Dasanu Annette M. Marleau Neil H. Riordan 《Cellular immunology》2010,260(2):75-82
Duchenne muscular dystrophy (DMD) is a lethal X-linked musculodegenerative condition consisting of an underlying genetic defect whose manifestation is augmented by inflammatory mechanisms. Previous treatment approaches using gene replacement, exon-skipping or allogeneic cell therapy have been relatively unsuccessful. The only intervention to mediate improvement in survival, albeit minor, is glucocorticoid treatment. Given this modality appears to function via suppression of underlying inflammation; we focus this review on the inflammatory response as a target for mesenchymal stem cell (MSC) therapy. In contrast to other cell based therapies attempted in DMD, MSC have the advantages of (a) ability to fuse with and genetically complement dystrophic muscle; (b) possess anti-inflammatory activities; and (c) produce trophic factors that may augment activity of endogenous repair cells. We conclude by describing one practical scenario of stem cell therapy for DMD. 相似文献
964.
Evolutionary Ecology - The role of mutations have been subject to many controversies since the formation of the Modern Synthesis of evolution in the early 1940ties. Geneticists in the early half of... 相似文献
965.
Saroj Ruchisansakun Arne Mertens Steven B Janssens Erik F Smets Timotheüs van der Niet 《Annals of botany》2021,127(2):267
Background and AimsFloral diversity as a result of plant–pollinator interactions can evolve by two distinct processes: shifts between pollination systems or divergent use of the same pollinator. Although both are pollinator driven, the mode, relative importance and interdependence of these different processes are rarely studied simultaneously. Here we apply a phylogenetic approach using the Balsaminaceae (including the species-rich genus Impatiens) to simultaneously quantify shifts in pollination syndromes (as inferred from the shape and colour of the perianth), as well as divergent use of the same pollinator (inferred from corolla symmetry).MethodsFor 282 species we coded pollination syndromes based on associations between floral traits and known pollination systems, and assessed corolla symmetry. The evolution of these traits was reconstructed using parsimony- and model-based approaches, using phylogenetic trees derived from phylogenetic analyses of nuclear ribosomal and plastid DNA sequence data.Key ResultsA total of 71 % of studied species have a bee pollination syndrome, 22 % a bimodal syndrome (Lepidoptera and bees), 3 % a bird pollination syndrome and 5 % a syndrome of autogamy, while 19 % of species have an asymmetrical corolla. Although floral symmetry and pollination syndromes are both evolutionarily labile, the latter shifts more frequently. Shifts in floral symmetry occurred mainly in the direction towards asymmetry, but there was considerable uncertainty in the pattern of shift direction for pollination syndrome. Shifts towards asymmetrical flowers were associated with a bee pollination syndrome.ConclusionFloral evolution in Impatiens has occurred through both pollination syndrome shifts and divergent use of the same pollinator. Although the former appears more frequent, the latter is likely to be underestimated. Shifts in floral symmetry and pollination syndromes depend on each other but also partly on the region in which these shifts take place, suggesting that the occurrence of pollinator-driven evolution may be determined by the availability of pollinator species at large geographical scales. 相似文献
966.
Jarrod Gott Leonore Bovy Emma Peters Sofia Tzioridou Stefano Meo aatay Demirel Mahdad Jafarzadeh Esfahani Pedro Reis Oliveira Thomas Houweling Alessandro Orticoni Anke Rademaker Diede Booltink Rathiga Varatheeswaran Carmen van Hooijdonk Mahmoud Chaabou Anastasia Mangiaruga Erik van den Berge Frederik D. Weber Simone Ritter Martin Dresler 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2021,376(1817)
Metacognitive reflections on one''s current state of mind are largely absent during dreaming. Lucid dreaming as the exception to this rule is a rare phenomenon; however, its occurrence can be facilitated through cognitive training. A central idea of respective training strategies is to regularly question one''s phenomenal experience: is the currently experienced world real, or just a dream? Here, we tested if such lucid dreaming training can be enhanced with dream-like virtual reality (VR): over the course of four weeks, volunteers underwent lucid dreaming training in VR scenarios comprising dream-like elements, classical lucid dreaming training or no training. We found that VR-assisted training led to significantly stronger increases in lucid dreaming compared to the no-training condition. Eye signal-verified lucid dreams during polysomnography supported behavioural results. We discuss the potential mechanisms underlying these findings, in particular the role of synthetic dream-like experiences, incorporation of VR content in dream imagery serving as memory cues, and extended dissociative effects of VR session on subsequent experiences that might amplify lucid dreaming training during wakefulness.This article is part of the theme issue ‘Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation''. 相似文献
967.
Joyce N. Njuguna Lindsay V. Clark Kossonou G. Anzoua Larisa Bagmet Pavel Chebukin Maria S. Dwiyanti Elena Dzyubenko Nicolay Dzyubenko Bimal Kumar Ghimire Xiaoli Jin Douglas A. Johnson Uffe Jørgensen Jens Bonderup Kjeldsen Hironori Nagano Junhua Peng Karen Koefoed Petersen Andrey Sabitov Eun Soo Seong Toshihiko Yamada Ji Hye Yoo Chang Yeon Yu Hua Zhao Stephen P. Long Erik J. Sacks 《Global Change Biology Bioenergy》2023,15(5):642-662
Miscanthus is a high-yielding bioenergy crop that is broadly adapted to temperate and tropical environments. Commercial cultivation of Miscanthus is predominantly limited to a single sterile triploid clone of Miscanthus × giganteus, a hybrid between Miscanthus sacchariflorus and M. sinensis. To expand the genetic base of M. × giganteus, the substantial diversity within its progenitor species should be used for cultivar improvement and diversification. Here, we phenotyped a diversity panel of 605 M. sacchariflorus from six previously described genetic groups and 27 M. × giganteus genotypes for dry biomass yield and 16 yield-component traits, in field trials grown over 3 years at one subtropical location (Zhuji, China) and four temperate locations (Foulum, Denmark; Sapporo, Japan; Urbana, Illinois; and Chuncheon, South Korea). There was considerable diversity in yield and yield-component traits among and within genetic groups of M. sacchariflorus, and across the five locations. Biomass yield of M. sacchariflorus ranged from 0.003 to 34.0 Mg ha−1 in year 3. Variation among the genetic groups was typically greater than within, so selection of genetic group should be an important first step for breeding with M. sacchariflorus. The Yangtze 2x genetic group (=ssp. lutarioriparius) of M. sacchariflorus had the tallest and thickest culms at all locations tested. Notably, the Yangtze 2x genetic group's exceptional culm length and yield potential were driven primarily by a large number of nodes (>29 nodes culm−1 average over all locations), which was consistent with the especially late flowering of this group. The S Japan 4x, the N China/Korea/Russia 4x, and the N China 2x genetic groups were also promising genetic resources for biomass yield, culm length, and culm thickness, especially for temperate environments. Culm length was the best indicator of yield potential in M. sacchariflorus. These results will inform breeders' selection of M. sacchariflorus genotypes for population improvement and adaptation to target production environments. 相似文献
968.
Claude Mande Victor Van Cakenberghe Lucinda Kirkpatrick Anne Laudisoit Luc De Bruyn Guy-Crispin Gembu Erik Verheyen 《Biotropica》2023,55(5):920-932
Assessing how bats respond to habitat attributes requires an integrative approach to reliably predict direct community-level effects. We focused on hipposiderid and pteropodid bats because of their diverse resource use patterns, body size ranges, and dispersal abilities. We combined an array of bat species-level characteristics with key forest stand characteristics that may covary with habitat use. Twelve stations were sampled in the Lomami and Yangambi landscapes, Democratic Republic of the Congo. We investigated whether species-level flight ability of bats and forest stand characteristics can affect bat commuting flights and community-level estimates of both species detection and habitat occupancy. We captured bats for 108 trap-nights. Three sampling events (early evening, middle of the night, and early morning) were replicated for each survey night. Hipposiderids showed an early evening flight peak, while flight activity of pteropodids was constant throughout the night, but increased around the middle of the night. Species capture probability decreased with higher wing loading in hipposiderids and was negatively correlated with higher wing aspect ratio in pteropodids. Forest occupancy of hipposiderids increased along the gradient towards waterways, while pteropodid occurrence was not directly linked to measured forest stand variables. This suggests a consequence of habitat patterns at larger spatial scales, which would need clarifying through additional data collection. We discuss these findings in terms of resource-use strategies of clutter-tolerant and clutter-intolerant species. We argue that the occurrence of specific bat species and their habitat use patterns can serve as surrogate measures of ecosystem health. 相似文献
969.
Gyrase inhibitors and thymine starvation disrupt the normal pattern of plasmid RK2 localization in Escherichia coli 下载免费PDF全文
Multicopy plasmids in Escherichia coli are not randomly distributed throughout the cell but exist as defined clusters that are localized at the mid-cell, or at the 1/4 and 3/4 cell length positions. To explore the factors that contribute to plasmid clustering and localization, E. coli cells carrying a plasmid RK2 derivative that can be tagged with a green fluorescent protein-LacI fusion protein were subjected to various conditions that interfere with plasmid superhelicity and/or DNA replication. The various treatments included thymine starvation and the addition of the gyrase inhibitors nalidixic acid and novobiocin. In each case, localization of plasmid clusters at the preferred positions was disrupted but the plasmids remained in clusters, suggesting that normal plasmid superhelicity and DNA synthesis in elongating cells are not required for the clustering of individual plasmid molecules. It was also observed that the inhibition of DNA replication by these treatments produced filaments in which the plasmid clusters were confined to one or two nucleoid bodies, which were located near the midline of the filament and were not evenly spaced throughout the filament, as is found in cells treated with cephalexin. Finally, the enhanced yellow fluorescent protein-RarA fusion protein was used to localize the replication complex in individual E. coli cells. Novobiocin and nalidixic acid treatment both resulted in rapid loss of RarA foci. Under these conditions the RK2 plasmid clusters were not disassembled, suggesting that a completely intact replication complex is not required for plasmid clustering. 相似文献
970.
Erik J. Wenninger Sanford D. Eigenbrode 《Entomologia Experimentalis et Applicata》2020,168(9):654-664
We previously described a putative aggregation pheromone in adults of the sugar beet root maggot, Tetanops myopaeformis (von Röder) (Diptera: Ulidiidae), comprising nine compounds identified from males. Here, we conducted a series of experiments aimed at simplifying the blend of compounds necessary to achieve attraction as well as determining the dose that maximizes captures when formulated into an attractant lure. In all experiments, females showed stronger and more consistent evidence of attraction than males. White sticky traps baited with different blends of pheromone compounds that included the major component, (R)-(−)-2-nonanol, showed significantly higher female captures relative to those baited with blends that excluded the major component. (R)-(−)-2-nonanol alone was at least as effective as any blend that included this compound with other minor pheromone components. Lures using racemic 2-nonanol were as effective as the (R) enantiomer for both females and males, with some evidence of weak attraction to the (S) enantiomer (which is not produced by males) observed as well. Maximum capture rates using racemic 2-nonanol were estimated to occur with doses of ca. 795.5 and 621.6 mg for females and males, respectively. Addition of 2-nonanol lures to standard orange sticky stake traps currently used to monitor flies increased captures of both sexes. The pheromone lure developed here could improve trapping efficiency of current monitoring programs for T. myopaeformis and may also be used to develop other management tools for this important pest of sugar beet. 相似文献