Georgia College & State University

About: Georgia College & State University is a education organization based out in Milledgeville, Georgia, United States. It is known for research contribution in the topics: Population & Higher education. The organization has 950 authors who have published 1591 publications receiving 37027 citations.

The presence of atrazine and atrazine‐degrading bacteria in the residential, cattle farming, forested and golf course regions of Lake Oconee

Abstract: Aims: To assess the concentration of atrazine in Lake Oconee and develop a qPCR assay as a potential marker for the presence of atrazine-degrading bacteria indicating atrazine contamination. Methods and Results: Water and sediment samples were collected from the Oconee Lake at four golf course sites, two residential sites, one cattle farming site and a forested site. Atrazine concentration at the study sites was determined using an ELISA kit and indicated the presence of atrazine from 0·72 ppb at the forested sites to 1·84 ppb at the golf course sites. QPCR results indicate the presence of atzA gene (atrazine chlorohydrolase) from 1·51 × 102 gene copies at the residential sites to 3·31 × 105 gene copies per 100 ml of water at the golf course regions of the lake and correlated (r = 0·64) with atrazine concentration. Sediment samples had higher atzA gene copies compared with the water samples (P < 0·05). Conclusions: Atrazine concentration and the highest quantity of atzA gene were detected in the golf course regions of the lake. Overall, atrazine concentration monitored in Lake Oconee was below the Environment Protection Agency (EPA) regulatory standards. Significance and Impact of the Study: Quantitative PCR is an efficient technique for assessing the presence of atrazine catabolism gene as a functional marker for atrazine-degrading bacteria and the presence of atrazine contamination.

Residence time effects on phase transformation of nanosilver in reduced soils

Abstract: Residence time effects on phase transformation of silver nanoparticles (AgNPs) (15-50 nm, with and without polyvinylpyrrolidone (PVP) coating) were investigated in reducing soils using experimental geochemistry and synchrotron-based x-ray techniques. After 30 days of anaerobic incubation, a substantial fraction of PVP-coated AgNPs (15 nm) were transformed into Ag₂S and or humic acid (HA) complexed Ag(I), whereas only the HA fraction was dominant in uncoated AgNPs (50 nm). Several investigations recently reported that sulfidation of AgNPs to Ag₂S was the predominant mechanism controlling the fate of AgNP in soil-water environments. However, this investigation showed each AgNP underwent particle-specific chemical transformations to different end compounds after 30 days. Considering the small contribution of Ag(I) dissolution from all AgNPs (less than 5%), we concluded that changes in solid-state chemical speciation of sorbed AgNPs was promoted by particle-specific interactions of NPs in soil chemical constituents, suggesting a critical role of soil absorbents in predicting the fate of AgNPs in terrestrial environments.

Combinatorial Proofs of Various q-Pell Identities via Tilings

Abstract: Recently, Benjamin, Plott, and Sellers proved a variety of identities involving sums of Pell numbers combinatorially by interpreting both sides of a given identity as enumerators of certain sets of tilings using white squares, black squares, and gray dominoes. In this article, we state and prove q-analogues of several Pell identities via weighted tilings.

The second wave of earthworm invasions in North America: biology, environmental impacts, management and control of invasive jumping worms

Abstract: The invasion of jumping worms, a small group of pheretimoid earthworm species from Asia, has increasingly become an ecological, environmental and conservation issue in forest ecosystems and urban-suburban landscapes around the world. Their presence is often noticed due to their high abundance, distinctive “jumping” behavior, and prominent granular casts on the soil surface. Although they are known to affect soil carbon dynamics and nutrient availability, no single paper has summarized their profound impacts on soil biodiversity, plant community, and animals of all trophic groups that rely on soil and the leaf litter layer for habitat, food, and shelter. In this study, we summarize the biology, invasion, and ecological impacts of invasive jumping worms across North America. We highlight potential impacts of this second wave of earthworm invasion, contrast them with the preceding European earthworm invasion in temperate forests in North America, and identify annual life cycle, reproductive and cocoon survival strategies, casting behavior and co-invasion dynamics as the key factors that contribute to their successful invasion and distinct ecological impacts. We then suggest potential management and control strategies for practitioners and policy makers, underscore the importance of coordinated community science projects in tracking the spread, and identify knowledge gaps that need to be addressed to understand and control the invasion.

Gender Development in African American Youth

Abstract: Using the organizing framework of Ruble, Martin, and Berenbaum (2006), we summarized literature on gender development in African American youth within six content areas: biological/categorical sex, activities and interests, personal-social attributes, social relationships, styles and symbols, and values regarding gender. Results with African Americans were compared with what is known about gender processes in other U.S. racial groups, and gaps in the literature were noted. Finally, we summarized the literature on socialization influences on gender development in African American youth, focusing particularly on parents and media. Our review shows that gender, along with race, plays a significant role in the development of African American youth, with many of these processes similar to what is found in youth of other racial/ethnic groups. Contextual factors such as family structure and racial context are important to take into account to best understand individual differences in the gender development of Bl...