354 research outputs found
Coiling and Maturation of a High-Performance Fibre in Hagfish Slime Gland Thread Cells
The defensive slime of hagfishes contains thousands of intermediate filament protein threads that are manufactured within specialized gland thread cells. The material properties of these threads rival those of spider dragline silks, which makes them an ideal model for biomimetic efforts to produce sustainable protein materials, yet how the thread is produced and organized within the cell is not well understood. Here we show how changes in nuclear morphology, size and position can explain the three-dimensional pattern of thread coiling in gland thread cells, and how the ultrastructure of the thread changes as very young thread cells develop into large cells with fully mature coiled threads. Our model provides an explanation for the complex process of thread assembly and organization that has fascinated and perplexed biologists for over a century, and provides valuable insights for the quest to manufacture high-performance biomimetic protein materials
Canadian Indians and the Great War for Civilization
Dr. Winegard has recently published two books: Indigenous Peoples of the Dominions and the First World War (Cambridge University Press) and For King and Kanata: Canadian Indians and the First World War (University of Manitoba Press)
Integrating Drama and Music into the Language Arts Curriculum: Its Effects on Student Self-Perception and Achievement
This researcher tested the effects that drama and music had on students within the language arts. Research participants included 19 fourth grade students randomly chosen from three language arts classes. For the three week duration of the study, classroom lessons included activities for singing, acting, improvisation, song writing, and games. The participants took a self-perception survey before and after the study. A second assessment tested students’ skills inventory, asking questions already covered in previous lessons. At the end of the study students were again tested. Results show that there was a significant increase in attention to classroom activity, self-esteem, and perceptions of language arts. All students improved their skills, those with the lowest pre-assessment had the largest increases. The daily lesson plan used in this study is included in the appendix
If you've got it, flaunt it : humans flaunt attractive partners for status and desirability
Title from PDF of title page (University of Missouri--Columbia, viewed on March 11, 2013).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. David C. GearyIncludes bibliographical references.M. A. University of Missouri--Columbia 2012."Dec 2012"Mate choices that are influenced by the mating decisions of peers, i.e., nonindependent choice, occur in many species including humans. Recent research on humans has shown that women are more attracted to men with attractive putative partners than those with less attractive partners. I frame human nonindependent mate choice in the context of a mate signalling theory (MST) and test predictions in two ecologically valid experiments. In study 1, I found that both men and women show off or "flaunt" attractive putative mates, and that men but not women hide or "conceal" unattractive ones. This effect was mediated by expected status and desirability of being seen with these partners. In study 2, I replicated the results of study 1 with a sample of only men. I further found, contrary to extant theoretical perspectives, that men desire to flaunt attractive putative mates equally to both opposite and same sex peers. Results are discussed in light of the MST, a potentially powerful generator of hypotheses and explanations for many facets of human mating
Design and test of a 100 ampere-hour nickel cadmium battery module
A feasibility study was conducted on the design and construction of a flight-worthy replaceable battery module consisting of four 100 A.H. nickel-cadmium rechargeable cells for large manned space vehicles. The module is planned to weigh less than 43 pounds and be fully maintainable in a zero-g environment by one man without use of special tools. An active environmental control system was designed for the temperature control of the module
Who is the fairest one of all? How evolution guides peer and media influences on female body dissatisfaction.
Much attention has focused on the influence of media images of thin women on body dissatisfaction among female viewers. Disagreement exists regarding the nature of media influences, with meta-analytic results suggesting only small effect sizes. Fewer researchers have focused on the role of peer influences and peer competition on female body dissatisfaction. Furthermore, the relation between body dissatisfaction and eating disorders may be more complex than is often implied in the media effects literature. Links between body dissatisfaction and eating disorders may be overstated, and some eating disorders, primarily anorexia nervosa, may not always be motivated primarily by body dissatisfaction. The current paper discusses these issues from an evolutionary perspective, examining how sociocultural forces influence the intensity of female competition and how such competition effects body dissatisfaction. Keywords: body dissatisfaction, eating disorders, mass media, mate selection, female sexuality Body dissatisfaction, particularly among women, has caused concern among scientists and policymakers for several decades. In Western societies, approximately 40%-50% of women express some level of body dissatisfaction. (e.g., In this review, we examine the evidence for media and peer influences on female body dissatisfaction and the hypothesized relation between body dissatisfaction and eating disorders. Regarding eating disorders, we focus specifically on anorexia nervosa (AN) and bulimia nervosa (BN). In the first section, we critically review contemporary psychology's focus on the media as a primary source of body dissatisfaction. In the second, we turn our attention to eating disorders, specifically focusing on secular trends in AN and BN as well as their cross-cultural prevalence. Evidence that these disorders are not "culturally bound" and that they are not increasing dramatically leads us to view skeptically claims that media are an important cause of eating disorders. The third section considers the evidence that peer influences are an important factor in causing body dissatisfaction in women. We consider it valuable to contrast both the evidence and relative focus of psychology on peer and media influences. In the fourth section we move from the research on body dissatisfaction and eating disorders to providing a theoretical explanation of these findings. We do so by briefly reviewing sexual selection theory as it pertains to female intra-and intersexual competition. In the last section, we present a preliminary model that integrates the previous literature reviewed and attempts to explain the complex relationship between media, peers, body dissatisfaction, and eating disorders. Our specific focus is on putative social factors that have intensified the implicit and explicit levels of competition between women and how these may influence body image concerns
Studies of Cardiac Muscle with a High Permeability to Calcium Produced by Treatment with Ethylenediaminetetraacetic Acid
Evidence for Prosody in Silent Reading
English speakers and expressive readers emphasize new content in an ongoing discourse. Do silent readers emphasize new content in their inner voice? Because the inner voice cannot be directly observed, we borrowed the cap-emphasis technique (e.g., “toMAYto”) from the pronunciation guides of dictionaries to elicit prosodic emphasis. Extrapolating from linguistic theories of focus prosody in spoken English, we predicted and found that silent readers in experiment 1 preferred cap-emphasized, newsworthy content (“James stole the BRACELET ) when the just-read story left them wondering what was stolen (compared with control trials). Readers preferred “JAMES stole the bracelet” when left wondering who the thief was. Experiment 2 generalized our findings to newsworthy function words and to a new behavioral measure, reaction time. As predicted, “He CAN” was judged more quickly and accurately following “Can he swim,” whereas “HE can” was judged more quickly and accurately following “Who can swim?” Our results suggest that readers engage focus prosody when they read silently
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