Truman C.C.,U.S. Department of Agriculture |
Nuti R.C.,U.S. Department of Agriculture |
Truman L.R.,Abraham Baldwin Agricultural College |
Catena | Year: 2010
Crop production in Georgia and the Southeastern U.S. can be limited by water. Highly-weathered, drought-prone soils are susceptible to runoff and erosion. Rainfall patterns generate runoff producing storms followed by extended periods of drought during the crop growing season. Thus, supplemental irrigation is often needed to sustain profitable crop production. Increased water retention and soil conservation would efficiently improve water use and reduce irrigation amounts/costs and sedimentation, and sustain productive farm land, thus improving producer's profit margin. Soil amendments, such as flue gas desulfurization (FGD) gypsum, have been shown to retain rainfall and/or irrigation water through increased infiltration while decreasing runoff (R) and sediment (E). Objectives were to quantify rainfall partitioning and sediment delivery improvements with surface applied FGD gypsum from an Ultisol managed to conventional till (CT) and to assess the feasibility of using FGD gypsum on agricultural land in southern Georgia. A field study (Faceville loamy sand, Typic Kandiudult) was established (2006, 2007) near Dawson, GA managed to CT, irrigated cotton (Gossypium hirsutum L.). FGD gypsum application rates evaluated were 0, 1.1, 2.2, 4.5, and 9 Mg ha -1. Gypsum treatments and simulated rainfall (50 mm h -1 for 1 h) were applied to 2-m wide×3-m long field plots (n=3). Runoff and E were measured from each 6-m 2 plot (slope=1%). FGD gypsum plots averaged 26% more infiltration (INF), 40% less R, 58% less E, 27% lower maximum R rates (R max), and 2 times lower maximum E rates (E max) than control plots. Values of INF and water for crop use increased, and R, E, R max, and E max decreased as FGD gypsum application rate increased. Values of INF, R, E, R max, and E max for 9 Mg ha -1 plots were as much as 17% greater, 35% less, 1.9 times less, 35% less, and 1.9 times less than those from other FGD gypsum plots, respectively; and 40% greater, 40% less, 2.2 times less, 52% less, and 2.9 times less than those from control plots, respectively. Applying FGD gypsum to agricultural lands is a cost-effective management practice for producers in Georgia that beneficially impacts natural resource conservation, producer profit margins, and environmental quality. Agriculture in the Southeast provides a viable market for the electric power industry to convert disposal costs of FGD gypsum into a profitable commodity.
PubMed | Max Planck Institute for Evolutionary Anthropology, University of Missouri - Kansas City, University of Chicago, University of Vienna and 8 more.
Type: Journal Article | Journal: Anatomical record (Hoboken, N.J. : 2007) | Year: 2016
Australopiths exhibit a number of derived facial features that are thought to strengthen the face against high and/or repetitive loads associated with a diet that included mechanically challenging foods. Here, we use finite element analysis (FEA) to test hypotheses related to the purported strengthening role of the zygomatic root and anterior pillar in australopiths. We modified our previously constructed models of Sts 5 (Australopithecus africanus) and MH1 (A. sediba) to differ in the morphology of the zygomatic root, including changes to both the shape and positioning of the zygomatic root complex, in addition to creating variants of Sts 5 lacking anterior pillars. We found that both an expanded zygomatic root and the presence of anterior pillars reinforce the face against feeding loads. We also found that strain orientations are most compatible with the hypothesis that the pillar evolved to resist loads associated with premolar loading, and that this morphology has an ancillary effect of strengthening the face during all loading regimes. These results provide support for the functional hypotheses. However, we found that an anteriorly positioned zygomatic root increases strain magnitudes even in models with an inflated/reinforced root complex. These results suggest that an anteriorly placed zygomatic root complex evolved to enhance the efficiency of bite force production while facial reinforcement features, such as the anterior pillar and the expanded zygomatic root, may have been selected for in part to compensate for the weakening effect of this facial configuration. Anat Rec, 300:171-195, 2017. 2016 Wiley Periodicals, Inc.
PubMed | Washington University in St. Louis, University of New South Wales, University of Texas at Dallas, University of Chicago and Abraham Baldwin Agricultural College
Type: Journal Article | Journal: Anatomical record (Hoboken, N.J. : 2007) | Year: 2016
The internal and external anatomy of the primate zygoma is central to orofacial function, health, and disease. The importance of variation in its gross morphology across extinct and extant primate forms has been established using finite element analysis, but its internal structure has yet to be explored. In this study, CT is used to characterize trabecular bone morphometry in two separate regions of the zygoma of humans and Pan. Trabecular anisotropy and orientation are compared with strain orientations observed in trabecular regions of finite element models of four Pan crania. The results of this study show that trabecular bone morphometry, anisotropy, and orientation are highly compatible with strain orientation and magnitude in the finite element models. Trabecular bone in the zygoma is largely orthotropic (with bone orientation differing in three mutually orthogonal directions), with its primary orientation lying in the mediolateral direction. Trabecular bone in the zygomatic region appears to be highly influenced by the local strain environment, and thus may be closely linked to orofacial function. Anat Rec, 299:1704-1717, 2016. 2016 Wiley Periodicals, Inc.
News Article | December 9, 2016
The International Nurses Association is pleased to welcome Vanessa C. Kelly Krull, RN, MSN, to their prestigious organization with her upcoming publication in the Worldwide Leaders in Healthcare. Vanessa C. Kelly Krull is a Registered Nurse and RN Clinical Consultant with over 16 years of experience and an extensive expertise in all facets of nursing, especially informatics, critical care, and as a consultant. She currently maintains positions as a Dell Services Consultant, Informatics Nurse Specialist, and as a Project Manager. Additionally, she is affiliated with Covenant Health. Vanessa graduated with her Nursing Degree from Abraham Baldwin Agricultural College in Tifton, Georgia. An advocate for continuing education, she then went on to earn her Bachelor Degree in Nursing and her Master of Science Degree in Nursing, both from the Chamberlain College of Nursing in Downers Grove, Illinois. Additionally, Vanessa is a Registered Nurse, Board Certified and keeps up to date with the latest advances in her field through professional memberships with the American Nurses Association, the American Nursing Informatics Association, GAHIMSS, and the International Nurses Association. For her excellence, Vanessa was inducted into the Sigma Theta Tau International Honor Society of Nursing. Vanessa attributes her great success to her passion for providing the best patient care possible, her passion for always learning something new, and maintains the highest level of quality care possible. She feels that she makes a difference helping direct patient care providers use the newest technologies in a way that allows them to successfully provide the best, and most up to date care possible. When she is not working, Vanessa enjoys horseback riding and volunteer work in her free time. Learn more about Vanessa C. Kelly Krull here: http://inanurse.org/network/index.php?do=/4133596/info/ and be sure to read her publication in the Worldwide Leaders in Healthcare.
Daly E.R.,Abraham Baldwin Agricultural College |
Fox G.A.,Oklahoma State University |
Enlow H.K.,Oklahoma State University
World Environmental and Water Resources Congress 2015: Floods, Droughts, and Ecosystems - Proceedings of the 2015 World Environmental and Water Resources Congress | Year: 2015
The jet erosion test (JET) is one of the most commonly used in situ methods of measuring erodibility parameters (critical shear stress, τc, and erodibility coefficient, kd) of cohesive soils. Several factors can influence the erodibility of cohesive soils, but the influence of these factors is not captured by conducting a few JETs at one discrete point in time and at one location on a streambank. Current practice largely ignores the parameter, spatial, and temporal relationships in erodibility. Furthermore, in many cases the erodibility parameters are not characterized in situ, but estimated empirically with relationships that may not be good predictors for all streambanks. Building upon previous studies, the objectives were to address variability in JET-derived erodibility parameters at a site scale and across a range of soil erodibility with respect to soil parameter correlations, temporal variability, spatial variability, and testing variability. Also, this research estimated the number of JETs required to accurately characterize erodibility. A total of 74 JETs were conducted within visually homogeneous streambank layers at three sites in Oklahoma along with measurements of soil physical parameters such as texture, bulk density, and moisture content. At the site-scale τc and kd varied by up to three orders of magnitude. While there were correlations between the erodibility parameters and measured soil parameters, there were no reliable relationships with strong predictive capabilities at any of the sites for any of the soil parameters. Also, there were no significant multiple linear regressions to predict τc and kd based on more than one soil parameter. Conducting three to five JETs per soil layer on a streambank typically provided an order of magnitude estimate of the erodibility parameters. Because the parameters were log-normally distributed, using empirical equations to predict erosion properties based on soil characteristics will likely contain high uncertainty and thus should be used with caution. This research exemplifies the need to conduct in situ measurements using the JET. © 2015 ASCE.
Thurber C.S.,University of Massachusetts Amherst |
Thurber C.S.,Abraham Baldwin Agricultural College |
Reagon M.,Ohio State University |
Olsen K.M.,Washington University in St. Louis |
And 2 more authors.
American Journal of Botany | Year: 2014
Premise of the study: Local adaptation in plants often involves changes in flowering time in response to day length and temperature. Many crops have been selected for uniformity in flowering time. In contrast, variable flowering may be important for increased competitiveness in weed species invading the agricultural environment. Given the shared species designation of cultivated rice (Oryza sativa) and its the invasive conspecific weed, weedy rice, we assessed the extent to which flowering time differed between these groups. We further assessed whether genes affecting flowering time variation in rice could play a role in the evolution of weedy rice in the United States.Methods: We quantified flowering time under day-neutral conditions in weedy, cultivated, and wild Oryza groups. We also sequenced two candidate gene regions: Hd1, a locus involved in promotion of flowering under short days, and the promoter of Hd3a, a locus encoding the mobile signal that induces flowering.Key results: We found that flowering time has diverged between two distinct weedy rice groups, such that straw-hull weeds tend to flower earlier and black-hull awned weeds tend to flower later than cultivated rice. These differences are consistent with weed Hd1 alleles. At both loci, weeds share haplotypes with their cultivated progenitors, despite significantly different flowering times.Conclusions: Our phenotypic data indicate the existence of multiple flowering strategies in weedy rice. Flowering differences between weeds and ancestors suggest this trait has evolved rapidly. From a weed management standpoint, there is the potential for overlap in flowering of black-hull awned weeds and crops in the United States, permitting hybridization and the potential escape of genes from crops. © 2014 Botanical Society of America.
Bechler D.L.,Valdosta State University |
Hightower P.,Abraham Baldwin Agricultural College |
Rousey J.,114 Surrey Circle |
Smith M.E.,Valdosta State University
Freshwater Crayfish | Year: 2014
Nest-traps, first used to study the cavity nesting fish Gobiosoma bosc, were used to study population structure, life history and behavior of Procambarus spiculifer, and data collected was compared to a life history study in the same river basin. Nest-trap occupancy rate was 41.7% with a total of 136 crayfish collected over a 208 day sampling period, March to October 2007. Collections involved 80 females, 54 males and two juveniles for whom gender could not be determined. Gender distributions by size classes were similar in pattern to that collected as part of the more extensive life history study, but statistical differences existed. Higher occupancy rates in traps correlated with below and above average rainfall events. One to five crayfish occupied individual nest-traps. Soft-shelled crayfish, shed exoskeleton and dead crayfish were found in traps. Besides conspecific inhabitants, five species of fish and seven invertebrate taxa occupied nest-traps with crayfish present. The results of this study indicate that valuable insight into population structure involving size relationships and gender analyses, behavioral activities involving conspecific and heterospecific co-inhabitants that occupy cavities can be acquired, and reasonably robust life history data comparable to more detailed studies can be acquired via nest-traps. Copyright © 2014 by The Author(s).
Kowalewski A.R.,Abraham Baldwin Agricultural College |
Rogers III J.N.,Michigan State University |
Crum J.R.,Michigan State University |
Dunne J.C.,Michigan State University
HortTechnology | Year: 2010
Drain tile installation into a native-soil athletic field and subsequent sand topdressing applications are cost-effective alternatives to complete field renovation. However, if cumulative topdressing rates exceed root system development, surface stability may be compromised. The objective of this research was to evaluate the effects of cumulative topdressing, over a compacted sandy loam soil, on the fall wear tolerance and surface shear strength of a kentucky bluegrass (Poa pratensis)- perennial ryegrass (Lolium perenne) stand. Research was initiated in East Lansing, MI, on 10 Apr. 2007. A well-graded, high-sand-content root zone (90.0% sand, 7.0% silt, and 3.0% clay) was topdressed at a 0.25-inch depth [2.0 lb/ft2 (dry weight)] per application, providing cumulative topdressing depths of 0.0, 0.5, 1.0, 1.5, or 2.0 inches applied from 11 July to 15 Aug. 2007. Fall traffic was applied twice weekly to all treatments from 10 Oct. to 3 Nov. 2007. In 2008, topdressing applications and traffic, as described earlier, were repeated on the same experimental plots. Results obtained from this research suggest that the 0.5-inch topdressing depth applied over a 5-week period in the summer will provide improved shoot density and surface shear strength in the subsequent fall. Results also suggest that topdressing rates as thick as 4.0 inches accumulated over a 2-year period will provide increased shoot density, but diminished surface shear strength.
Kiser L.C.,Abraham Baldwin Agricultural College |
Fox T.R.,Virginia Polytechnic Institute and State University |
Carlson C.A.,Virginia Polytechnic Institute and State University
Forests | Year: 2013
Following fertilization of forest plantations, high accumulations of nutrients in the forest floor creates the need to assess rates of forest floor decomposition and nutrient release. The study site was a 25-year old experimental loblolly pine plantation in the North Carolina Sandhills Region. Soluble and insoluble N, P, carbohydrate and phenol-tannin fractions were determined in foliage and litter by extraction with trichloroacetic acid. The long-term forest floor decomposition rate and decomposition and nutrient release in an experiment simulating removal of the overstory canopy were also determined. In litter, insoluble protein-N comprised 80%-90% of total-N concentration while soluble inorganic- and organic-P comprised 50%-75% of total-P concentration explaining forest floor N accumulations. Fertilization did not increase soluble carbohydrates in litter and forest floor decomposition rates. Loblolly pine forest floor decomposing in environmental conditions simulating removal of the overstory canopy was greatly accelerated and indicated 75% mass loss and release of 80% of the N pool within one year. This could result in a loss of substantial quantities of N at harvest due to low N uptake by seedlings in the newly planted next rotation suggesting management of the forest floor at harvest is essential to conserve site N capital in these N limited systems. © 2013 by the authors.
Agency: NSF | Branch: Standard Grant | Program: | Phase: ADVANCED TECH EDUCATION PROG | Award Amount: 204.44K | Year: 2010
In response to the rapid implementation of a variety of new geospatially-based technologies into the agricultural sector, this project is improving a number of existing technical agriculture programs by integrating real-time sensor and monitor technologies into teaching curricula through context-based experiential learning. The project is developing an information-enhanced, technologically-advanced agricultural outdoor laboratory at the institutions working farm that is serving as a focal point for integrating a variety of courses in the curriculum. Instead of implementing geospatially-based sensor and monitor technologies independently within each discipline, information from a variety of disciplines is being integrated through activities that are utilizing the newly installed technologies. These are generating system-level information that is providing students with decision making and planning experiences. The project is providing expanded student participation in contextual technology projects, developing and integrating new courses that incorporate sensor and monitor technologies into existing agricultural education programs, and training faculty to understand and utilize these new technologies. The project is enhancing the agricultural workforce by producing technologically adept graduates who are bringing innovative technologies and skills to employers. Moreover, the project is providing an improved pathway for highly-trained transfer students who wish to continue their education at a four-year institution, providing opportunities to develop and maintain strong cross-disciplinary interactions among faculty, and recruiting students from traditionally under-served rural populations into technological fields. Project development and ultimate success are being informed and enabled by a strong formative evaluation component, and summative evaluation results are being presented at national agricultural education meetings and shared with others via the ATE AgroKnowledge Center.