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Less-structured time in children's daily lives predicts self-directed executive functioning.
Executive functions (EFs) in childhood predict important life outcomes. Thus, there is great interest in attempts to improve EFs early in life. Many interventions are led by trained adults, including structured training activities in the lab, and less-structured activities implemented in schools. Such programs have yielded gains in children's externally-driven executive functioning, where they are instructed on what goal-directed actions to carry out and when. However, it is less clear how children's experiences relate to their development of self-directed executive functioning, where they must determine on their own what goal-directed actions to carry out and when. We hypothesized that time spent in less-structured activities would give children opportunities to practice self-directed executive functioning, and lead to benefits. To investigate this possibility, we collected information from parents about their 6-7 year-old children's daily, annual, and typical schedules. We categorized children's activities as "structured" or "less-structured" based on categorization schemes from prior studies on child leisure time use. We assessed children's self-directed executive functioning using a well-established verbal fluency task, in which children generate members of a category and can decide on their own when to switch from one subcategory to another. The more time that children spent in less-structured activities, the better their self-directed executive functioning. The opposite was true of structured activities, which predicted poorer self-directed executive functioning. These relationships were robust (holding across increasingly strict classifications of structured and less-structured time) and specific (time use did not predict externally-driven executive functioning). We discuss implications, caveats, and ways in which potential interpretations can be distinguished in future work, to advance an understanding of this fundamental aspect of growing up
Data analysis / BEBR No. 540
Includes bibliographical references."In any comprehensive research project, there are essentially five steps. First, one starts with a literature review with regard to a particular research question. Second, one seeks to develop a theory. Third, the research question is finalized, frequently in the form of a hypothesis to be tested. Fourth, data are collected. Fifth, the subject matter of this paper, the data are analyzed in order to come to a resolution of the research question. There are two general approaches to analyzing research data. If the data were gathered concerning a 'research question,' a description of the data may be sufficient. However, if the data were gathered to accept or reject a formal hypothesis, statistical analysis is usually in order. This paper briefly surveys the principal data analysis methodologies that are available.
Plant sphingolipids: their importance in cellular organization and adaption
Sphingolipids and their phosphorylated derivatives are ubiquitous bio-active components of cells. They are structural elements in the lipid bilayer and contribute to the dynamic nature of the membrane. They have been implicated in many cellular processes in yeast and animal cells, including aspects of signaling, apoptosis, and senescence. Although sphingolipids have a better defined role in animal systems, they have been shown to be central to many essential processes in plants including but not limited to, pollen development, signal transduction and in the response to biotic and abiotic stress. A fuller understanding of the roles of sphingolipids within plants has been facilitated by classical biochemical studies and the identification of mutants of model species. Recently the development of powerful mass spectrometry techniques hailed the advent of the emerging field of lipidomics enabling more accurate sphingolipid detection and quantitation. This review will consider plant sphingolipid biosynthesis and function in the context of these new developments. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner
Introduction of Vegetative and Reproductive Characters into Trifolium Repens by Interspecific Hybridisation
Interspecific hybridization between white clover (Trifolium repens L.) and ball clover (T.nigrescens) and Caucasian clover (T.ambiguum) is a means of improving the reproductive growth and persistency of T.repens. F1 hybrids between T.repens and T.nigrescens were produced without ovule culture and confirmed as true hybrids by chromosome counts, isoenzyme analysis and leaf markers. Their growth habit was generally intermediate between the two parents. After backcrossing to T.repens the BC1 and BC2 hybrids had more of the characteristics associated with T.repens though they retained some of the greater reproductive growth of T.nigrescens. Hybrids between T.repens and T.ambiguum were produced using ovule culture. Two F1 seedlings were produced with a morphology intermediate to the two parents. 35 BC1 seedlings were produced with a similar morphology to the F1 but with less of the T.ambiguum growth habit. The BC2 population showed greater variability in the expression of characters from Caucasian clover and contained only 10% of plants with the combined stoloniferous and rhizomatous habit. The implications for improving the growth of T.repens by interspecific hybridization are discussed
Using Hermetia illucens to process Ugandan waragi waste
Waragi, a form of homemade gin, is produced throughout Uganda in both legal and illegal breweries. Waste produced during the illegal brewing process is predominantly disposed of via indiscriminate dumping into surrounding environments and reports from local communities have indicated this to be harmful to crops and livestock. The larvae of Hermetia illucens are documented to consume a wide range of otherwise unappealing waste products. In addition to this, the prepupal stages of the larvae can serve as a high-quality protein feed for animal livestock. Therefore, the feasibility of the larvae of H. illucens to digest waragi waste was evaluated. A dietary toxicity trial was run to establish an LC50 value for waragi inclusion in larval diets. This was followed by a larger scale trial utilising waragi waste in combination with various in situ available feed stuffs to further assess the viability of processing waragi waste using H. illucens. Larvae were able to eat diets composed of up to 85% waragi waste without any significant impact on survival or growth. When combined with locally available feed sources, e.g. chicken offal, cottonseed cake, sunflower meal or groundnut cake, larvae showed high survival and growth rates on diets including 25% waragi waste. Results indicate that H. illucens larvae may be a useful tool in processing waragi waste
The effect of an initial high-quality feeding regime on the survival of Gryllus bimaculatus (black cricket) on bio-waste
Previous studies have led to claims that insects can offer a solution to several food security hurdles, one of which is the processing of food waste. However, although it has been demonstrated that some insects survive well on bio-waste (e.g. Hermetia illucens), no study, has to date, demonstrated success rearing species more commonly used for human consumption, such as crickets, on biowaste from hatching. This trial aimed to establish if the black cricket, Gryllus bimaculatus, can be reared successfully on bio-waste from hatching. Since, in other livestock sectors it has been established that nutritional requirements vary with age and that diet must be altered accordingly to achieve the best growth, e.g. chick feed to layer mash in chickens, the present trial used a similar feeding regime of an initially high-quality feed to see if this allowed the subsequent survival of crickets on low quality bio-waste products. Pilot trials have demonstrated poor to no survival on beer waste and cow manure and mid-level survival on unprocessed vegetable waste with chicken feed as the control. Based on this, feed regimes of either 1 or 2 weeks high quality feed (chicken feed) and then either 2 or 3 weeks of low quality feed (beer waste or vegetable waste) were tested. Results showed that even 1 week of high quality feed makes a significant difference in survival and end size of crickets subsequently reared on low-quality bio-waste
Impact of heat processing on the nutritional content of Gryllus bimaculatus (black cricket)
Insects are increasingly suggested as a potential novel solution to global nutrition challenges. However, limited research is available on what impact varied rearing and processing methods ultimately have on the nutritional content of edible insects. This trial examines the impact of six distinct diets, some based on bio-waste, on the nutritional content of the commonly consumed cricket, Gryllus bimaculatus. Results showed a significant impact of diet on the protein, micronutrient and fatty acid content of crickets. However, the majority of these relationships were not distinctly linear; in general, an increase in a certain area in the diet did not equate to the same increase in the crickets. The only nutritional element with a direct dietary relationship was α-linolenic acid, which increased as dietary content did. Following on from this the effect of various levels of heat processing on subsequent nutritional profile was studied. Results showed that different temperatures, from freeze drying up to 120℃ had no significant impact on protein or micronutrient content. However, the fatty acid content was significantly impacted by higher temperature processing. Freeze-drying crickets conserved significantly more of the longer chained polyunsaturated fatty acids than drying at 120℃. It is evident from ongoing research that insects hold potential as a source of essential nutrients and fatty acids, but when reared on low-quality feed and processed at high temperatures they are unlikely to be of any more nutritional benefit than foods presently used in nutritional interventions
Feeling the Heat: Investigating the dual assault of Zymoseptoria tritici and Heat Stress on Wheat (Triticum aestivum)
As a result of climate change, field conditions are increasingly challenging for crops. Research has shown how elevated temperatures affect crop performance, yet the impact of temperature on host-pathogen relationships remains unknown. Understanding the effects of combined abiotic and biotic stresses on crop plants and the plant-microbial interaction is crucial in developing strategies to improve crop stress tolerance and manage diseases effectively. Lipids sense, signal, and mitigate temperature elevation effects, and lipid remodelling plays a key role in the plant and fungal response to heat stress. Our study uses a systems approach to examine the Z. tritici wheat model system, combining transcriptomics, lipidomics, and phenotyping to decipher the impact of high-temperature stress on the plant-pathogen interaction.
Microscopy in vivo and RNA-Seq analyses confirmed that Z. tritici responds to high-temperature treatments with morphological and transcriptomic changes. Temperature-related configuration of the transcriptome was associated with the accessory chromosomes and expression of ‘accessory’ pan-genome-derived genes. Metabolism-related gene expression predominated, indicated by GO enrichment and analysis of KOG classes, and large-scale lipid remodelling was likely given the proportion of lipid transport and metabolism-related expression changes in response to temperature. Changes in lipid content and composition were then validated by LC-MS analysis. Heat-responsive fungal genes and pathways, including scramblase family genes, are being tested by reverse genetics to ascertain their importance for fungal adaption to elevated temperatures.
Elevated temperature schemes were applied to wheat to study the impact of combined stress on the plant-pathogen interaction, based on long-term climate data from Rothamsted Research, using transcriptomic, lipidomic and phenotypic analyses. Comparing non-infected and infected wheat plants under typical and elevated temperatures. Our initial analysis of the transcriptomic data indicates a delay in the development of Z. tritici, followed by its adaptation to the warmer environment. Once the infection was established, the fungus exhibited resilience to the impact of higher external temperatures. Our results indicate that temperature elevations associated with climate change directly impact plant-pathogen interactions. Furthermore, the study demonstrates a need for further detailed understanding to sustain crop resilience
O adsorption and incipient oxidation of the Mg(0001) surface
First principles density functional calculations are used to study the early
oxidation stages of the Mg(0001) surface for oxygen coverages 1/16 <= Theta <=
3 monolayers. It is found that at very low coverages O is incorporated below
the topmost Mg layer in tetrahedral sites. At higher oxygen-load the binding in
on-surface sites is increased but at one monolayer coverage the on-surface
binding is still about 60 meV weaker than for subsurface sites. The subsurface
octahedral sites are found to be unfavorable compared to subsurface tetrahedral
sites and to on-surface sites. At higher coverages oxygen adsorbs both under
the surface and up. Our calculations predict island formation and clustering of
incorporated and adsorbed oxygen in agreement with previous calculations. The
calculated configurations are compared with the angle-scanned x-ray
photoelectron diffraction experiment to determine the geometrical structure of
the oxidized Mg(0001) surface.Comment: 10 pages, 5 figure
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