Motivation and Performance, Blog 9

Student blog posts from the Great VCU Bike Race Book

Relation Between Particle Mass and Number for Submicrometer Airborne Particles

The relationship between particle mass and the number of ambient air particles for the submicrometer size range was examined using a Tapered Element Oscillating Microbalance to determine the mass concentration, and a Scanning Mobility Particle Sizer to determine the volume concentration and total number of particles. After validating the techniques through their application to the estimation of submicrometer particle density for two laboratory generated aerosols of known bulk density (Sodium Chloride and Di-2-ethylhexyl-sebacate), the submicrometer fraction of laboratory generated Environmental Tobacco Smoke and ambient air were examined and an estimate of the average submicrometer particle densities for these aerosols found to be 1.18 g cm-3 and 1.7 g cm-3 respectively

Black Seoul

The project explores the connections between Black culture and South Korean culture and how they are overlapping

Glucagon-like peptide-1 (GLP-1) increases in plasma and colon tissue prior to estrus and circulating levels change with increasing age in reproductively competent Wistar rats

There is a well-documented association between cyclic changes to food intake and the changing ovarian hormone levels of the reproductive cycle in female mammals. Limited research on appetite-controlling gastrointestinal peptides has taken place in females, simply because regular reproductive changes in steroid hormones present additional experimental factors to account for. This study focussed directly on the roles that gastrointestinal-secreted peptides may have in these reported, naturally occurring, changes to food intake during the rodent estrous cycle and aimed to determine whether peripheral changes occurred in the anorexigenic (appetite-reducing) hormones peptide-YY (PYY) and glucagon-like peptide-1 (GLP-1) in female Wistar rats (32-44 weeks of age). Total forms of each peptide were measured in matched fed and fasted plasma and descending colon tissue samples for each animal during the dark (feeding) phase. PYY concentrations did not significantly change between defined cycle stages, in either plasma or tissue samples. GLP-1 concentrations in fed plasma and descending colon tissue were significantly increased during proestrus, just prior to a significant reduction in fasted stomach contents at estrus, suggesting increased satiety and reduced food intake at this stage of the cycle. Increased proestrus GLP-1 concentrations could contribute to the reported reduction in food intake during estrus and may also have biological importance in providing the optimal nutritional and metabolic environment for gametes at the potential point of conception. Additional analysis of the findings demonstrated significant interactions of ovarian cycle stage and fed/fasted status with age on GLP-1, but not PYY plasma concentrations. Slightly older females had reduced fed plasma GLP-1 suggesting that a relaxation of regulatory control of this incretin hormone may also take place with increasing age in reproductively competent females

Ion Regulation by miR-51 in C. elegans Muscle Tissue

MicroRNAs serve a regulatory function in an array of cellular pathways. Using existing immunoprecipitation data that identified distinct differences in miRNA and gene enrichment in muscle cells in C. elegans, a preliminary RNAi screen was run to identify potential significant miRNA targets in muscle cells. The screen identified two potential genes, twk-12 and calm-1, predicted to be regulated by miRNA-51. In order to determine the importance of miR-51 regulation of different muscle targets, RT-PCR was performed in a number of miRNA mutant strains and 3’-UTR reporters were constructed for twk-12 and calm-1. Based on these experiments, twk-12 may be regulated by mir-51, and calm-1, twk-28, and other important genes in muscle cells are likely subject to miRNA regulation. To determine any physiological consequences of miRNA regulation, ion assays were performed by subjecting worms to different concentrations of pharmacological agents that alter cellular ion concentrations. Mir-51(-) mutant worms proved to be more susceptible to altered calcium concentrations, suggesting a role of miR-51 in calcium regulation

Unit organization of the topic agriculture for a seventh-grade course in occupations

Thesis (Ed.M.)--Boston University, 1938. This item was digitized by the Internet Archive

Biological and Contextual Predictors of the Stability of Behavioural Inhibition in Early Childhood

Persistently elevated behavioural inhibition (BI) in children confers increased risk for anxiety disorders. However, little research has jointly examined exogenous and endogenous factors that may moderate BI stability in early childhood. To explore whether parent (i.e., parental overinvolvement, parent anxiety) and child (i.e., 5-HTTLPR and BDNF val66met genotype, positive emotionality) factors influenced the stability of early BI, a community sample of 371 preschoolers and their caregivers completed observational measures of child temperament, observational and questionnaire measures of parenting, and parent interviews for anxiety disorder history. Child BI at age 3 interacted with children’s 5-HTTLPR variants to predict age 5 BI; children with at least one copy of the short allele exhibited less stability of BI, indexed via associations between age 3 and age 5 BI. Findings are consistent with previous work indicating the 5-HTTLPR short variant increases plasticity to contextual influences, thereby serving to decrease BI stability in early childhood

A zooarchaeological study of butchery and bone fat processing practices among early Neolithic farming societies in central Europe

This thesis presents the results of zooarchaeological investigations into diet in Neolithic central Europe. The aim of these investigations was to gain a better understanding of animal carcass processing, particularly dietary decisions made concerning intensity of exploitation of meat and fat resources. The primary focus was the Linearbandkeramik (LBK) culture, a sedentary community of farmers dating from c. 5500-4900BC in central Europe suspected to be the first society to utilise milk and its products in this region. The adoption of dairying, currently under scrutiny by the NeoMilk project, would have increased the availability of fat on settlements, and could have affected the way in which people utilised primary animal products. Using in-depth zooarchaeological analysis of butchery, fracture and fragmentation, this thesis presents a snapshot of Neolithic meat and fat exploitation. Patterns of butchery and heat exposure suggest differential cooking practices between sites, with a possible focus on nutrient retention at some, contrasted with a cultural preference for roasting at others. Intensive processing of bone fats, namely bone grease, was not detected at any site and it is likely that the domesticated LBK diet rendered this practice unnecessary to subsistence. Bone marrow was a much more commonly exploited resource, but variation was considerable between sites. It is possible that the intensification of dairying had a significant effect on the utilisation of bone marrow. Sites with the most evidence for milk use, detected through lipid residue and osteoarchaeological evidence, show less intensive exploitation of bone marrow than those with little or no evidence of dairying. This thesis therefore presents evidence of zooarchaeologically detectable dietary decisions being made in the face of adoption of new foodstuffs