Tag: Poster 46

The Indigenous Siberian Health and Adaptation Project: Adiponectin, Body Composition, and Cardiovascular Health among the Yakut (Sakha) of Siberia

Presenter: Elizabeth Streeter

Mentor: James Josh Snodgrass

PM Poster Presentation

Poster 46

Adiponectin is a hormone secreted by adipocytes that is involved in a number of metabolic processes. A decreased production of adiponectin is an important risk factor linking obesity with other cardiovascular risk factors. However, few population-based studies have been conducted on this emerging biomarker, and virtually all existing data come from Western clinical settings. This study, part of a long-term research project focused on the indigenous Yakut (Sakha) of northeastern Siberia, examines potential sex differences in adiponectin and investigates relationships with body composition and blood pressure. The data were collected in 2009 from 255 healthy Yakut adults (≥18 years old; 137 females, 118 males) and used to test two hypotheses: 1) adiponectin levels will be higher in females compared to males; and 2) adiponectin will be inversely related to body composition and blood pressure measures. Results indicate a significant sex difference, with greater concentrations in females compared to males (P < 0.01). Adiponectin was negatively correlated with several anthropometric parameters, including body mass index (BMI), waist circumference, and percent body fat (all measures P < 0.01) among males, and BMI (P < 0.05), WC (P < 0.01), and percent body fat (P < 0.01) among females. However, adiponectin among the Yakut was not significantly correlated with blood pressure in either sex, which raises questions about its utility as a cardiovascular risk marker in this population.

Measuring Finger Ratios in Hands and Bones: Testing the Reliability and Accuracy of Post-mortem Methods of Second-to-Fourth Digit Ratio Assessment in Primates

Presenter: Josie Beavers

Co-Presenters: Enrique Gomez

Faculty Mentor: Frances White, Stephen Frost

Presentation Type: Poster 46

Primary Research Area: Science

Major: Biological Anthropology

The ratio of length of the second digit to fourth digit indicates individual exposure to gonadal hormones in utero (Manning 2002). 2D:4D is therefore used as a proxy for prenatal androgen exposure; a lower 2D:4D indicates more prenatal androgen exposure, and a higher 2D:4D indicates less prenatal androgen exposure (Manning 2002). The most accurate way to measure 2D:4D is to measure from the proximal crease to the most distal end of the digit in living and recently deceased individuals (Manning 2002). However, in many cases an individual may be mummified or decomposed prior to measuring 2D:4D. Our research seeks to determine the accuracy of different 2D:4D measurement methods by comparing obtained 2D:4D values from the fully fleshed, skinned, disarticulated, and articulated phalangeal bones of the same rhesus macaque individual (Macaca mulatta). We also determined if the position of the hand (i.e. flattened palm or curled fingers) yielded significantly different 2D:4D ratios. Our findings indicate that the 2D:4D values obtained in all flattened measurements closely correlated (r = 0.997 – 0.999), but the measurements obtained from the curled hands were not as closely correlated (r = 0.962 – 0.982). These results suggest that 2D:4D measurements on articulated bones are most closely correlated to the fully fleshed 2D:4D measurement. These findings will allow scientists to more accurately obtain 2D:4D measurements on non-living specimens in the future.

The genetic basis of the first connections in the brain

Presenter(s): Anisha Adke – Biology

Faculty Mentor(s): Adam Miller

Poster 46

Research Area: Biology

Funding: Vice President for Research and Innovation (VPRI) Undergraduate Fellowship, UROP Mini-grant

An estimated 100 billion neurons form the human brain, equal to the number of stars in our galaxy. Nervous system function emerges from connections, or synapses, between these neurons, which are either electrical or chemical. The synapses form a wired circuit that emerges over development as directed by an organism’s genetic code. The first synapses that form are critical to normal circuit wiring, as they lay the foundation upon which mature circuits are built. Research has shown that these first synapses are electrical, but it is unknown which genes are responsible for the connections. This project aims to identify the genes required for the first synapses and investigate their roles from a molecular, circuit, and behavioral standpoint. This will provide a critical understanding of nervous system wiring, as genetic defects that alter normal circuit wiring are linked to neurodevelopmental disorders such as autism and schizophrenia.
To explore the genes responsible for electrical synapses, we examined the first spinal cord circuits that form in zebrafish. We identified genes-of-interest using RNAseq and are finding when, where, and how these genes control the formation of the first synapses, analyzing them for neural network and behavioral changes. Preliminary behavioral analysis suggests that the gene Cx46.8 is involved in early circuit formation, while mutations in Cx35.1, Cx34.1, Cx35.5, Cx34.7, and Cx43.4 show no visible disruption. Future work using RNA in situ hybridization will characterize Cx46.8 localization, allowing for a better understanding of where the gene is at work. We are also using fluorescent calcium indicators to characterize the mutations and the resulting disruptions to circuit wiring in order to understand the roles of the genes in early electrical synapse formation.

Relating Pumice Permeability to Vesicle Attributes using 3D Printed Models

Presenter(s): Frederick Ede

Faculty Mentor(s): Thomas Giachetti

Poster 46

Session: Sciences

Pumice is a highly porous rock composed of volcanic glass bearing dense and complex networks of vesicles—bubbles preserved in solid rock resulting from the exsolution of volatiles such as water and carbon dioxide from the magmatic melt during its ascent to the surface. These vesicles often become interconnected, rendering the magma permeable to buoyant gas which escapes into the host rock or the atmosphere. This process, which is known as outgassing, reduces the overpressure in the magma and may prevent fragmentation and explosive eruption. How permeability varies depends on the size, shape, and abundance of vesicles and fractures. The goal of my project is to analyze the physical properties of 3D printed pumice models. While some data can be obtained from virtual pumice models, having physical representations of the tortuous, constricting passages that render pumice permeable will lead to a better understanding of real-world pumice permeability. Studying the properties of volcanic products grants insight into the eruption process. Understanding how vesicle networks develop and how they impact eruption style will lead to enhanced volcanic hazard prediction and mitigation. To aid in the effort of better understanding the effects that developing vesicle networks have on the eruption process of a volcano, I will establish functional relationships between pumice permeability and vesicle and fracture characteristics such as number density, size, and shape.