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 & Context (language use). The organization has 950 authors who have published 1591 publications receiving 37027 citations.

Phytoremediation Potential of Helianthus annuus and Hydrangea paniculata in Copper and Lead-Contaminated Soil

Abstract: This study was conducted to assess the hyperaccumulation and phytoremediation potential of copper (Cu) and lead (Pb) in Hardy ‘Limelight’ Hydrangea (Hydrangea paniculata) and the common sunflower (Helianthus annuus). The study also investigated the capacity of these two plants to transpire the metals in a temperature-controlled greenhouse. Plants were grown for 4 weeks and periodically watered with known elemental concentrations of copper oxide nanoparticles, copper sulfate, and lead nitrate. Both H. annuus and H. paniculata accumulated significant amounts of Cu and Pb to be classified as hyperaccumulator species. H. annuus took up significant amounts of Cu in the shoots, specifically the leaves (Cu max. = 1368 ppm), and easily translocated it from stem to leaf (translocation factor (TF) ranged from 2.7 to 81.0). Pb was not as easily taken up and translocated (TF = 0.6) as Cu was by this species. H. paniculata took up Cu and Pb in high concentrations but preferentially stored more metals in the stems (Cu max. = 1757 ppm; Pb max. = 780 ppm) than in the leaves (Cu max. = 126 ppm; Pb max. = 35 ppm). The translocation ability of H. paniculata was much lower for both metals compared to H. annuus. Both Cu and Pb transpired from H. annuus at concentrations of 0.04 and 0.005 ppm, respectively.

Nomenclatural novelties in Miconia (Melastomataceae: Miconieae)

Abstract: The Miconieae (Melastomaceae) are a strictly Neotropical group comprising over 1900 species. The tribe is characterized by inflorescences that are terminal or axillary, but not cauliflorous (except a few species of Charianthus, Clidemia, and Mecranium), flowers subtended by only one pair of bracteoles (or none at all), with anthers that lack a pedoconnective, leaves without long acicular raphides, and berry fruits. Generic delimitations within the Miconieae have been notoriously complex, and phylogenetic analyses have shown that Miconia is paraphyletic with many other genera embedded within it. These nested genera include Anaectocalyx, Calycogonium, Catocoryne, Charianthus, Clidemia, Conostegia, Killipia, Leandra, Maieta, Mecranium, Necramium, Ossaea, Pachyanthus, Pleiochiton, Sagraea, Tetrazygia, and Tococa. In the absence of a workable solution that allows the subdivision of the tribe into smaller, morphologically recognizable and monophyletic genera, it has been previously proposed that only one genus be recognized in the tribe. Here we present the necessary taxonomic and nomenclatural changes necessary to recognize Miconia as the sole genus within Miconieae.

Web-enabled wireless technology: an exploratory study of adoption and continued use intentions

Abstract: This study builds upon previous research by comparing and contrasting the decision to adopt wireless technologies with the decision to continue to use wireless technologies. In the context of web-enabled cell phones, we propose, test and compare the predictive ability of two value-based models using a multi-group analysis. The findings suggest that regardless of whether an individual was choosing to adopt or continue to use a web-enabled cell phone, perceived usefulness, enjoyment and perceived fee influenced perceived value. In turn, perceived value influenced the adoption or continued use decision. Technicality had a significant negative effect on perceived value in the context of continued use, but not for adoption. Our results also suggested a shift in the importance of benefits in the formation of perceived value; perceived usefulness played a greater role for adopters, while enjoyment played a better role for continued users. Lastly, our results indicated that uncertainty avoidance did not mediate the relationship between perceived value and intention in either the continued use or adoption contexts, while habit was significant in its mediation of the relationship between perceived value and continued use intention. Collectively, habit and perceived value explained 71% of the variation in continued use intention.

2MASS/SDSS Close Major-Merger Galaxy Pairs

Abstract: We select a close "major-merger candidate" galaxy pair sample in order to calculate the K_s luminosity function (LF) and pair fraction representative of the merger/interaction component of galaxy evolution in the local universe. The pair sample (projected separation 5 h^(–1) kpc ≤ r≤ 20 h ^(–1) kpc, K_s -band magnitude difference ΔK_s ≤ 1 mag) is selected by combining the Two Micron All Sky Survey (2MASS) with the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5). The resulting data set contains 340 galaxies covering 5800 deg^2. A stellar mass function is also translated from the LF. A differential pair fraction displays nearly constant fraction of galaxy pairs as a function of galaxy mass from 10^9 to 10^(11.5) M_☉ . The differential pair fraction is less subject to absolute magnitude bias due to survey limitations than the standard total pair fraction. These results suggest that major-merger candidate pairs in the 0