3,961 research outputs found
Memory disorders in children
Memory disorders are a frequent consequence of a variety of childhood neurological conditions. We will review the characteristics of memory disorders as a function of the main four memory systems: short-term memory, episodic memory, semantic memory, and procedural memory. For each system, we will identify the most typical cerebral and/or genetic correlates, and we will discuss the impact of impairment of each memory system on everyday life functioning. © 2013 Elsevier B.V
Discovery and identification of a male-killing agent in the Japanese ladybird Propylea japonica (Coleoptera: Coccinellidae).
BACKGROUND: Endosymbionts that manipulate the reproduction of their hosts have been reported widely in invertebrates. One such group of endosymbionts is the male-killers. To date all male-killers reported are bacterial in nature, but comprise a diverse group. Ladybirds have been described as a model system for the study of male-killing, which has been reported in multiple species from widespread geographic locations. Whilst criteria of low egg hatch-rate and female-biased progenic sex ratio have been used to identify female hosts of male-killers, variation in vertical transmission efficiency and host genetic factors may result in variation in these phenotypic indicators of male-killer presence. Molecular identification of bacteria and screening for bacterial presence provide us with a more accurate method than breeding data alone to link the presence of the bacteria to the male-killing phenotype. In addition, by identifying the bacteria responsible we may find evidence for horizontal transfer between endosymbiont hosts and can gain insight into the evolutionary origins of male-killing. Phylogenetic placement of male-killing bacteria will allow us to address the question of whether male-killing is a potential strategy for only some, or all, maternally inherited bacteria. Together, phenotypic and molecular characterisation of male-killers will allow a deeper insight into the interactions between host and endosymbiont, which ultimately may lead to an understanding of how male-killers identify and kill male-hosts. RESULTS: A male-killer was detected in the Japanese coccinellid, Propylea japonica (Thunberg) a species not previously known to harbour male-killers. Families produced by female P. japonica showed significantly female-biased sex ratios. One female produced only daughters. This male-killer trait was maternally inherited and antibiotic treatment produced a full, heritable cure. Molecular analysis identified Rickettsia to be associated with the trait in this species of ladybird. CONCLUSION: We conclude that P. japonica is host to a bacterial male-killer that is vertically inherited with variable transmission efficiency. Rickettsia presence correlates with the male-killing trait, but there is some variation in the phenotypic expression of the trait due to interaction with host factors. Phylogenetic analysis using the 16S rRNA and 17 kDa antigen genes suggests there may have been horizontal transfer of Rickettsial male-killers between different ladybird hosts.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Cycle of 6ths Progression: Annotated Bibliography
The Cycle of 6ths is a chord progression that I first heard about from the Jazz guitarist Ted Greene, who was a skilled music theorist and had two books published on guitar harmony and chord progressions. Ted stated that he first learned of the cycle of 6ths from studying J.S. Bach. You may be wondering what a chord cycle of ____ is? A chord cycle is when you move chords in a certain intervallic pattern, eventually the cycle comes back around to the starting chord. For instance, if you move chords in 4ths starting on C you would have the following; C, F, Bb, Eb, Ab, Db eventually you move through all 12 keys and come back to C. The cycle of 6ths is a similar idea but you move to relative major or minor of each key. For instance: C major to A minor to F Major to D minor to Bb major and so on, like the other cycle you would eventually come back to C major. I have heard of progressions involving 4ths and 5ths, but never 6ths. John Coltrane does use a cycle of 3rds which would be the inverse pattern of 6ths, but the descending pattern is much harder to find. I hope that some of the information provided here can help shed some light on what they cycle of 6ths is, and why it should be a valuable part of music scholarship
Turning the mind’s eye inward: the interplay between selective attention and working memory
Historically, cognitive sciences have considered selective attention and working memory as largely separated cognitive functions. That is, selective attention as a concept is typically reserved for the processes that allow for the prioritization of specific sensory input, while working memory entails more central structures for maintaining (and operating on) temporary mental representations. However, over the last decades various observations have been reported that question such sharp distinction. Most importantly, information stored in working memory has been shown to modulate selective attention processing – and vice versa. At the theoretical level, these observations are paralleled by an increasingly dominant focus on working memory as (involving) the attended part of long-term memory, with some positions considering that working memory is equivalent to selective attention turned to long-term memory representations – or internal selective attention. This questions the existence of working memory as a dedicated cognitive function and raises the need for integrative accounts of working memory and attention. The next step will be to explore the precise implications of attentional accounts of WM for the understanding of specific aspects and characteristics of WM, such as serial order processing, its modality-specificity, its capacity limitations, its relation with executive functions, as well as the nature of attentional mechanisms involved. This research topic in Frontiers in Human Neuroscience aims at bringing together the latest insights and findings about the interplay between working memory and selective attention
Strategies to Decrease Physical Aggression in Elementary Students with Autism Spectrum Disorder
A growing number of individuals have been diagnosed with autism spectrum disorder. Students with autism spectrum disorder may exhibit a variety of physically aggressive and self-injurious behaviors that are problematic and difficult for caregivers and educators to manage. Due to these behaviors, educators and caregivers are facing burnout and exhaustion. The research shows that there are interventions that can help identify the function of the behaviors and are effective in reducing the physical aggression or self-injurious behaviors. The focus of this review is to identify therapeutic interventions that have a positive impact on elementary students with autism spectrum disorder who have demonstrated physically aggressive behaviors and self-injurious behaviors. This review focused on interventions that are evidence based practices and that can be implemented within the educational setting
Comparison of screening techniques for traits relating to drought tolerance in grain sorghum
Call number: LD2668 .T4 AGRN 1987 M34Master of ScienceAgronom
Factors Affecting The Academic And Athletic Self-Determined Motivation Of NJCAA Division III Student-Athletes: A Mixed Methods Study
Student-athletes who participate at Division III technical and community colleges across the country are a unique population of students who have special needs and interests. Their academic needs and interests likely led them towards a technical and community college education, but these students have also chosen to participate in athletics. Deci and Ryan’s (1985) self-determination theory (SDT) of motivation has long been utilized to examine students’ basic psychological needs (autonomy, competence, relatedness) and their impact on academic motivation (intrinsic, extrinsic, amotivation ) and success; yet, little of this research has focused on community college students or student-athletes within a community college setting. In a recent pilot study, independent samples t-tests revealed that nonstudent-athletes, compared to student-athletes, had significantly higher self-reported grade point averages, perceived success, intrinsic motivation, and extrinsic motivation. A limitation was that several of the study’s scales had poor reliabilities, prompting the use of improved measures in the current study. The current study employed new scales to examine the motivations of National Junior College Athletic Association (NJCAA) Division III student-athletes who, in stark contrast to their Division I and II counterparts, are not allowed to accept financial remuneration for their participation in intercollegiate athletics. More specifically, the purpose of this study was to examine the role basic psychological needs play in the academic motivation of student-athletes compared to nonstudent-athletes, as well as how these needs impact student-athletes motivation for athletics.
A convergent parallel mixed method design was used to triangulate quantitative results with qualitative findings (Creswell & Plano Clark, 2011). Participants consisted of students at a Midwestern community and technical college (N = 238) completing an online survey containing Likert-style and open-ended questions. Independent samples t-test revealed that nonstudent-athletes had significantly higher levels of intrinsic motivation for academics compared to student-athletes, and student-athletes were found to have significantly higher levels of amotivation than nonstudent-athletes. Multiple regressions revealed that the level of autonomy, competence, and relatedness a nonstudent-athlete has for academics has a significant impact on their academic motivation. In contrast, multiple regressions did not reveal any significant findings for student-athletes levels of autonomy, competence, and relatedness for academics as a predictor of academic motivation. It was found that a student-athletes level of relatedness for athletics was a significant predictor of their level of athletic motivation.
Open-ended responses were analyzed using qualitative data analysis techniques of codes, and themes. The analysis of the open-ended responses produce codes which added to the depth and understanding from quantitative results. The qualitative analysis provided support for quantitative survey questions and results by allowing student-athletes and nonstudent-athletes to provide their own specific motivational factors.
The findings in this study helped to create support for the generalizability of research found in larger NCAA Division I universities to that of smaller NJCAA Division III institutions. Additionally this study helped to provide data and validate an updated scale on sports motivation. Based on the results of this study it is hoped that instructors, coaches, advisors, and administrators will be better informed of the motivational needs of student-athletes in comparison to their nonstudent-athlete counterparts and take actions that target the specific academic needs of student-athletes
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