67 research outputs found
Sea Urchin Covering Behavior: A Comparative Review
Covering behavior in sea urchins is an important aspect of many species’ ecology and has a variety of perceived benefits including food source, mechanical defense, shielding from sunlight, and predator protection. The goal of this study was to determine whether an urchin genus’s main benefit from this form of crypsis is correlated with either phylogenetic relationships or environmental factors (ocean depth and climate). To evaluate this hypothesis, a literature review was conducted on 15 urchin genera that use the covering reaction. The function of this behavior for the aforementioned genera was both mapped onto a phylogeny and evaluated, based on the climate and depth of the genera’s habitats to determine whether the patterns exist. The results suggest that phylogenetic relationships provide a more functional predictive tool for determining the purpose of covering in an urchin genus than its environment. This conclusion is useful for understanding the biology of sea urchins as well as how the covering reaction relates to the many other cryptic behaviors used by animal species
The associations between serum brain-derived neurotrophic factor, potential confounders, and cognitive decline: A longitudinal study
Brain-derived neurotrophic factor (BDNF) plays a role in the maintenance and function of neurons. Although persons with Alzheimer's disease have lower cortical levels of BDNF, evidence regarding the association between circulating BDNF and cognitive function is conflicting. We sought to determine the correlates of BDNF level and whether BDNF level was prospectively associated with cognitive decline in healthy older adults. We measured serum BDNF near baseline in 912 individuals. Cognitive status was assessed repeatedly with the modified Mini-Mental Status Examination and the Digit Symbol Substitution test over the next 10 years. We evaluated the association between BDNF and cognitive decline with longitudinal models. We also assessed the association between BDNF level and demographics, comorbidities and health behaviors. We found an association between serum BDNF and several characteristics that are also associated with dementia (race and depression), suggesting that future studies should control for these potential confounders. We did not find evidence of a longitudinal association between serum BDNF and subsequent cognitive test trajectories in older adults, although we did identify a potential trend toward a cross-sectional association. Our results suggest that serum BDNF may have limited utility as a biomarker of prospective cognitive decline
Serum brain-derived neurotrophic factor: Determinants and relationship with depressive symptoms in a community population of middle-aged and elderly people
OBJECTIVES: Brain-derived neurotrophic factor (BDNF) is involved in major depressive disorder and neurodegenerative diseases. Clinical studies, showing decreased serum BDNF levels, are difficult to interpret due to limited knowledge of potential confounders and mixed results for age and sex effects. We explored potential determinants of serum BDNF levels in a community sample of 1230 subjects. METHODS: Multiple linear regression analyses with serum BDNF level as the dependent variable were conducted to explore the effect of four categories of potential BDNF determinants (sampling characteristics, sociodemographic variables, lifestyle factors and somatic diseases) and of self-reported depressive symptoms (Beck's Depression Inventory (BDI). RESULTS: Our results show that BDNF levels decline with age in women, whereas in men levels remain stable. Moreover, after controlling for age and gender, the assays still showed lower serum BDNF levels with higher BDI sum scores. Effects remained significant after correction for two main confounders (time of sampling and smoking), suggesting that they serve as molecular trait factors independent of lifestyle factors. CONCLUSIONS: Given the age-sex interaction on serum BDNF levels and the known association between BDNF and gonadal hormones, research is warranted to delineate the effects of the latter interaction on the risk of psychiatric and neurodegenerative diseases
Manipulating the Hype: contemporary art's response to media cliches
Manipulating the Hype addresses art’s reaction to the barrage of signs produced by the media. The paper researches contemporary art’s response to clichéd media stereotypes and elucidates artists’ multifaceted perspective on overtly obvious yet widely embraced paradigms marketed by the media. Contemporary art’s strategic reconfiguration of media stereotypes is a valuable introspection upon the superficiality and impracticability of advertising and entertainment industry constructs. By reconsidering the mediated image, art has the ability to inspire reevaluation of cultural values. The thesis additionally attempts to ascertain the reinterpretation of media stereotypes as a common thread linking principal art movements and historically significant artworks from around the world since 1960. How does contemporary art respond to the extensive cultural influence of the media? Is a reaction to mass media a thematic commonality linking contemporary artists in the age of globalization? Manipulating the Hype is a dual outcome investigation comprised of written thesis and studio practice. The written thesis combines experience from a lengthy professional practice with historical and theoretical research. The visual thesis consists of twelve photographic works taken at on the Big Island of Hawaii. The images juxtapose artificial icons of power from popular culture with the natural force of the active lava flow. The process of research discloses how the advertising and entertainment industries capitalize upon innate human desires through the manipulative proliferation of archetypal imagery. Furthermore, the thesis establishes the widespread retort to media clichés as a palpable commonality in studio practices worldwide. The findings in the research make evident that although contemporary art does not have sufficient influence to reform the media, it can heighten public awareness of media tactics
Long-Term Course of Brain-Derived Neurotrophic Factor Serum Levels in a Patient Treated with Deep Brain Stimulation of the Lateral Habenula
Discriminating and classifying odontocete echolocation clicks in the Hawaiian Islands using machine learning methods.
Odontocete spatial patterns and temporal drivers of detection at sites in the Hawaiian islands.
Maps of Moorea.
<p>(a) Map of the South Pacific, with the location (red box), latitude, and longitude of Moorea, French Polynesia noted. (b) Map of Moorea showing the field site between the motus Tiahura and Fareone (blue dot) and collection spot at Haapiti (red dot).</p
Urchin cover in the field.
<p>Percent cover of algae and coral rubble on urchins in found partially underneath or totally underneath rocks in the motu Tiahura reef.</p
Experimental study set up.
<p>Diagram of urchin test setup, depicting the tub divided in two, the two urchins (in black) and the two cover types. Red plastic cover is represented by red rectangles, and clear cover is represented by clear rectangles with purple borders.</p
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