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Nuclear movement is a fundamental process of eukaryotic cell biology. Skeletal muscle presents an intriguing model to study nuclear movement because its development requires the precise positioning of multiple nuclei within a single cytoplasm. Furthermore, there is a high correlation between aberrant nuclear positioning and poor muscle function. Although many genes that regulate nuclear movement have been identified, the mechanisms by which these genes act are not known. Using Drosophila melanogaster muscle development as a model system and a combination of live-embryo microscopy and laser ablation of nuclei, we have found that clustered nuclei encompass at least two phenotypes that are caused by distinct mechanisms. Specifically, Ensconsin is necessary for productive force production to drive any movement of nuclei, whereas Bocksbeutel and Klarsicht are necessary to form distinct populations of nuclei that move to different cellular locations. Mechanistically, Ensconsin regulates the number of growing microtubules that are used to move nuclei, whereas Bocksbeutel and Klarsicht regulate interactions between nuclei.

Nuclear movement is a fundamental process of eukaryotic cell biology. Skeletal muscle presents an intriguing model to study nuclear movement because its development requires the precise positioning of multiple nuclei within a single cytoplasm. Furthermore, there is a high correlation between aberrant nuclear positioning and poor muscle function. Although many genes that regulate nuclear movement have been identified, the mechanisms by which these genes act is not known. UsingDrosophila melanogastermuscle development as a model system, and a combination of live-embryo microscopy and laser ablation of nuclei, we have found that phenotypically similar mutants are based in different molecular disruptions. Specifically, ensconsin (DrosophilaMAP7) regulates the number of growing microtubules that are used to move nuclei whereas bocksbeutel (Drosophilaemerin) and klarsicht (DrosophilaKASH-protein regulate interactions between nuclei.

Background Hospital-associated infections (HAI) such as methicillin-resistant Staphylococcus aureus (MRSA) can have devastating consequences. The World Health Organization created the 5 moments for hand hygiene. It was identified in the neonatal intensive care unit (NICU) pod setting that health care workers did not always recognize opportunities due to workflow complexities. It was hypothesized that introducing hand hygiene simulations would increase hand hygiene awareness which would decrease prevalence of HAI MRSA screen positive NICU infants. Methods This was a pre/post study performed in a level 4 NICU with 54 beds from February 2018 through November 2019. Participants included 146 nurses, 30 physicians, 18 respiratory therapists, and 5 additional therapists. In January 2019, each discipline created a scenario which guided the participant through a clinical situation and monitored opportunities for hand hygiene. Simulations were carried out in empty pods in the NICU to closely mimic actual working conditions. MRSA screening was performed via nasal MRSA PCR or culture with testing of infants born outside the hospital on admission and routine testing of all infants every two weeks. The rate of MRSA-positive infants' pre-intervention and post-intervention was obtained, and a chi-squared test was utilized to compare the rates and determine statistical significance (p-value Results In the 11 months prior to the intervention, there were 13 infants with positive HAI MRSA screens across 11,010 patient days (1 per 847). In the subsequent 11 months, there were 6 infants with positive HAI MRSA screens across 12,191 patient days (1 per 2,032) When comparing these two rates, the p-value is 0.067. Conclusions We observed a decrease in the rate of infants with positive HAI MRSA screens following our introduction of hand hygiene simulations although that difference did not reach statistical significance. The fact that the scenarios were created by frontline care providers was one of the keys to success.

Using Drosophila muscle development as a model system makes possible the identification of genetic pathways, temporal regulation of development, mechanisms of cellular development, and physiological impacts in a single system. Here we describe the basic techniques for the evaluation of the cellular development of muscle in Drosophila in both embryos and in larvae. These techniques are discussed within the context of how the LINC complex contributes to muscle development.

OBJECTIVE The aim of this study was to investigate the association between school connectedness and performance in standardized test scores and whether this association was moderated by ethnic private regard. METHOD The study combines self-report data with school district reported data on standardized test scores in reading and math and free and reduced lunch status. Participants included 436 Mexican-origin youth attending a middle school in a southwestern U.S. state. Participants were on average 12.34 years of age (SD = .95) and 51.8% female and 48.2% male. RESULTS After controlling for age, gender, free and reduced lunch status, and generational status, school connectedness and ethnic private regard were both positive predictors of standardized test scores in reading and math. Results also revealed a significant interaction between school connectedness and ethnic private regard in predicting standardized test scores in reading, such that participants who were low on ethnic private regard and low on school connectedness reported lower levels of achievement compared to participants who were low on ethnic private regard but high on school connectedness. At high levels of ethnic private regard, high or low levels of school connectedness were not associated with higher or lower standardized test scores in reading. CONCLUSION The findings in this study provide support for the protective role that ethnic private regard plays in the educational experiences of Mexican-origin youth and highlights how the local school context may play a role in shaping this finding. (PsycINFO Database Record

Gemellais a genus of Gram-positive bacteria found in the digestive tract of humans. They rarely cause systemic illness but have been recently implicated in several serious infections. We report infective endocarditis caused byGemella bergeriin a 23-year-old with a bicuspid aortic valve status post-intervention in infancy.

Using Drosophila muscle development as a model system makes possible the identification of genetic pathways, temporal regulation of development, mechanisms of cellular development, and physiological impacts in a single system. Here we describe the basic techniques for the evaluation of the cellular development of muscle in Drosophila in both embryos and in larvae. These techniques are discussed within the context of how the LINC complex contributes to muscle development.

Drosophila is used as a model system to show that the common phenotype of mispositioned nuclei occurs via distinct mechanisms in Emery–Dreifuss muscular dystrophy and centronuclear myopathy., Muscle cells are a syncytium in which the many nuclei are positioned to maximize the distance between adjacent nuclei. Although mispositioned nuclei are correlated with many muscle disorders, it is not known whether this common phenotype is the result of a common mechanism. To answer this question, we disrupted the expression of genes linked to Emery–Dreifuss muscular dystrophy (EDMD) and centronuclear myopathy (CNM) in Drosophila and evaluated the position of the nuclei. We found that the genes linked to EDMD and CNM were each necessary to properly position nuclei. However, the specific phenotypes were different. EDMD-linked genes were necessary for the initial separation of nuclei into distinct clusters, suggesting that these factors relieve interactions between nuclei. CNM-linked genes were necessary to maintain the nuclei within clusters as they moved toward the muscle ends, suggesting that these factors were necessary to maintain interactions between nuclei. Together these data suggest that nuclear position is disrupted by distinct mechanisms in EDMD and CNM.

Background: Body mass index (BMI) is widely accepted in determining obesity. Skinfold thickness measurements have been commonly used to determine percentage of body fat. Hypothesis: The authors hypothesize that because BMI does not measure fat directly but relies on body weight alone, a large percentage of athletic adolescents will be misclassified as obese by BMI. Design: Cross-sectional study. Methods: To compare BMI and skinfold measurements as indicators for obesity in the adolescent athletic population, anthropometric data (height, weight, percentage body fat, age, and sex) were recorded from 33 896 student athletes (average age, 15 years; range, 11-19 years) during preparticipation physical examinations from 1985 to 2003. BMI was calculated from height and weight. Percentage of body fat was determined by measuring skinfold thickness. Results: According to their BMI percentile, 13.31% of adolescent athletes were obese. Using the skinfold method, only 5.95% were obese. Of those classified as obese by the BMI, 62% were considered false positives by the skinfold method. In contrast, there was a 99% probability that the nonobese by BMI would not be obese by the skinfold method (negative predictive value = 0.99). Conclusions: BMI is a measurement of relative body weight, not body composition. Because lean mass weighs far more than fat, many adolescent athletes are incorrectly classified as obese based on BMI. Skinfold testing provides a more accurate body assessment than BMI in adolescent athletes. Clinical Relevance: Correct body composition data can help to provide better diet and activity guidelines and prevent the psychological problems associated with being labeled as obese.

Cells in vivo exist in a dynamic environment where they experience variable mechanical influences. The precise mechanical environment influences cell-cell interactions, cell-extracellular matrix interactions, and in-turn, cell morphology and cell function. Therefore, the ability of each cell to constantly and rapidly alter their behavior in response to variations in their mechanical environment is essential for cell viability, development, and function. Mechanotransduction, the process by which mechanical force is translated into a biochemical signal to activate downstream cellular responses, is thus crucial to cell function during development and homeostasis. Although much research has focused on how protein complexes at the cell cortex respond to mechanical stress to initiate mechanotransduction, the nucleus has emerged as crucial to the ability of the cell to perceive and respond to changes in its mechanical environment. This additional method for mechanosensing allows for direct transmission of force through the cytoskeleton to the nucleus, which can increase the speed at which a cell changes its transcriptional profile. This review discusses recent work demonstrating the importance of the nucleus in mediating the cellular response to internal and external force, establishing the nucleus as an important mechanosensing organelle.

The present research investigated whether competition influences children's artistic creativity and intrinsic motivation toward an art activity. Study 1 tested the hypothesis that boys' creativity would be enhanced by competition, while girls' creativity would be undermined. Fifty children (aged 6–10) made paper collages in one of two conditions; half competed for prizes and half did not. Results supported our hypotheses, and further showed that when children self-segregated by gender, the impact of competition was much more pronounced. Study 2 was designed to clarify the unexpected gender-segregation finding from Study 1. The Children's Sex Role Inventory [Boldizar, J.P. (1991). Assessing sex typing and androgyny in children: the Children's Sex Role Inventory. Developmental Psychology , 27 , 505–515] was administered to 143 children (aged 6–11). One week later, these children made paper collages in one of four conditions; in addition to manipulating competition, assigned seating ensured that half of children were segregated by gender and half were not. Following the collage activity, an intrinsic and extrinsic motivation questionnaire was administered. Masculine children reported higher levels of intrinsic motivation when competing and when segregated by gender; they also reported higher levels of extrinsic motivation, especially when segregated by gender. These findings demonstrate that gender role is an important factor in determining children's responses to competition.

Using archival data, the relationship of appearance to personality was investigated from childhood to age 60. Lagged effects of appearance on personality and vice versa, as well as accuracy of appearance stereotypes, were assessed. For men, lagged effects of attractiveness on personality were consistent with a self fulfilling prophecy; for adolescent boys, lagged effects of babyfaceness on personality were consistent with a self-defeating prophecy; for women, lagged effects of personality on attractiveness were consistent with a Dorian Gray effect, whereby early personality produces a congruent later appearance. There was no evidence for accuracy of the baby-face stereotype, which was significantly inaccurate for adolescent boys. Accuracy of the attractiveness stereotype required effects of a stable earlier appearance on later personality or a stable earlier personality on later appearance.

Three studies tested the hypothesis that babyfaced adolescent boys would compensate for the undesirable expectation that they will exhibit childlike traits by behaving contrary to it. Studies 1 and 2 revealed that babyfaced boys from middle- and lower class samples, including a sample of delinquents, showed higher academic achievement than their mature-faced peers, refuting the stereotype of babyfaced people as intellectually weak. In the lower class samples, this compensation effect was moderated by IQ and socioeconomic status (SES), variables that influence the ability to overcome low expectations. Study 3 showed that babyfaceness also can produce negative compensatory behaviors. Low-SES babyfaced boys were more likely than their mature-faced peers to be delinquent, and babyfaced delinquents committed more crimes, refuting the stereotype of babyfaced people as warm, submissive, and physically weak.

Structural qualities of honest-looking faces, developmental relationships between perceived and real honesty, and actual honesty of honest-looking people were investigated. Babyfaceness, attractiveness, facial symmetry, and large eyes each had positive, independent effects on perceived honesty, revealing a babyface overgeneralization effect, an attractiveness halo effect, and the metaphorical associations "wide-eyed innocence" and "crooked character. " Consistent with a self-fulfilling prophecy, men who looked more honest early in life became more honest later, particularly when appearance was stable. Women showed an "artifice"effect: Those less honest early in life became more honest-looking later. Differential accuracy in perceiving honesty in men and women accompanied these developmental effects. Honesty was accurately read in men whose early appearance of honesty was stable. Honesty was incorrectly read in women whose early real honesty was stable. When these individual differences were ignored, real and perceived honesty were unrelated.

Two archival studies examined the impact of people's appearance on the status and type of civilian and military jobs they hold. Study 1 found that, although appearance was not related to job status, taller men had higher incomes. Additionally, appearance was significantly related to the type of jobs people held. Attractive women and tall men held jobs requiring traits more consistent with the attractiveness halo, while babyfaced women and short men held jobs more consistent with the babyface stereotype. These effects remained after controlling for job-relevant personality and educational variables, suggesting an unjustified bias toward people with certain appearances. Study 2 found that heavier men had lower job status, as reflected in military rank attainment. However, this relationship was eliminated when controlling for intelligence and dependability. Also, babyfaced men achieved higher status through being marginally more likely to win a military award. This unexpected effect was attributed to the contrast between heroic actions and the babyface stereotype. Finally, appearance affected the type of military experience men had. Heavier men were more likely to be in situations involving gunfire or casualties. These studies make an important contribution by extending laboratory findings to the real world, exploring the effects of appearance on job type as well as status, and providing evidence that appearance effects are not solely due to covariation with bona fide job qualifications.

A popular stereotype of creative people is that they approach their work with a kind of crazed intensity, often forgoing sleep, food, and other seeming necessities of life in order to advance their creative work. Undoubtedly, this view is one source of the widespread belief that creativity stems from madness. Although the connection between creativity and insanity remains a controversial point, there is considerable anecdotal and empirical evidence that creative production does require a high level of motivation. For example, the novelist John Irving reported spending as many as 12 hours per day, for several consecutive days, while writing his novels. When asked what drove him to work so hard, even years after attaining wide readership, fame, and financial success, he replied: “The unspoken factor is love. The reason I can work so hard at my writing is that it's not work for me” (from an interview reported in Amabile, 1989, p. 56). What motivation drives creative activity? Is it generally based in the love that Irving describes? Does it derive from the desire to attain ever more wealth and fame, or are there other motivational forces at work? This chapter reviews theory and research on the motivation for creativity, revealing that, although creativity can arise from a complex interplay of motivational forces, motivation that stems from the individual's personal involvement in the work - love, if you will - is crucial for high levels of creativity in any domain.

We review research on accurate social perception at zero acquaintance and apply a Gibsonian ecological approach to redress several shortcomings. We argue that recent use of Brunswik's lens model to determine what physical qualities accurately communicate psychological traits has limited utility because it fails to consider the structured information provided by configural physical qualities that is central to Gibson's (1979) theory. We elaborate a developmental model of relationships between physical and psychological qualities that highlights research needed to identify configural physical qualities that may inform accurate perceptions. This model and tenets of the ecological theory yield several hypotheses regarding such qualities. Finally, we advocate the value of studying perceived affordances (opportunities for acting, interacting, or being acted upon) because this will focus attention on the neglected issue of contextual influences on social perception accuracy, and because affordances may be perceived more accurately than global personality traits.