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The ability to explain scientific phenomena is a key feature of scientific literacy, and engaging students' prior knowledge, especially their alternate conceptions, is an effective strategy for enhancing scientific literacy and developing expertise. The gap in knowledge about the alternate conceptions that novices have about many of Earth's complex phenomena (National Research Council, 2012), however, makes this type of engagement in geoscience courses challenging. This study helps to fill this gap by identifying and describing how novices to geoscience explain a complex scientific phenomenon, hurricane formation. Using a pragmatism methodology, 326 students in introductory-level geoscience courses at two public universities in the United States of America, in Georgia (n = 168) and Nebraska (n = 158), were surveyed. The questionnaire was designed to target and collect novices' explanations of a single complex Earth phenomenon--hurricane formation. Constant comparative analyses of textual content and diagrams revealed a variety of alternate conceptions. The data suggests that novices seldom invoke scientific first principles, which students matriculating through the education system are expected to learn before college, in their explanations. Two theoretical models synthesize the alternate conceptions and illustrate pathways of conceptual change along which students might move from more novice-like to more expert-like ways of scientific thinking. Our findings provide a basis for the development of instructional activities that aid students in developing more expert-like conceptions of hurricane formation and other complex Earth phenomena.

Emerging infectious diseases threaten the survival of wildlife populations and species around the world. In particular, amphibians are experiencing population declines and species extinctions primarily in response to two pathogens, the fungus Batrachochytrium dendrobatidis (Bd) and the iridovirus Ranavirus (Rv). Here, we use field surveys and quantitative (q)PCR to compare infection intensity and prevalence of Bd and Rv across species and seasons on Jekyll Island, a barrier island off the coast of Georgia, USA. We collected oral and skin swabs for 1 year from four anuran species and three families, including two native hylids (Hyla cinerea and Hyla squirella), a native ranid (Rana sphenocephala), and the invasive rain frog Eleutherodactylus planirostris. Bd infection dynamics did not vary significantly over sampling months, but Rv prevalence and intensity were significantly higher in fall 2014 compared to spring 2015. Additionally, Rv prevalence and intensity were significantly higher in E. planirostris than in the other three species. Our study highlights the potential role of invasive amphibians as drivers of disease dynamics and demonstrates the importance of pathogen surveillance across multiple time periods and species to accurately capture the infectious disease landscape. [ABSTRACT FROM AUTHOR]

Initial cases of Ebola in the U.S. raise varied legal issues as discussed at a late-breaking session at the 2014 Public Health Law conference. Session presenters share their perspectives on (1) state and local powers to quarantine and isolate persons, and (2) hospital preparedness underlying the treatment of Ebola patients. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the potential for enantioselective transformation and accumulation, the enantiomer distributions of seven polychlorinated biphenyl (PCB) atropisomers were measured in the sediment and biota from a sub-tropical estuary heavily contaminated with Aroclor 1268, a technical mixture of highly chlorinated PCB congeners. Enantiomer fractions (EFs) of PCBs 91, 95, 136, 149, 174, 176, and 183 in marsh sediment, invertebrate, forage and predatory fish species, and bottlenose dolphins were determined. Non-racemic EFs greater than 0.75 were found in sediments for PCBs 136 and 174, likely the result of microbial dechlorination. Although enantiomer fractions in grass shrimp (Palaemonetes spp.) mirrored those of sediment, fish species had EFs that differed significantly from sediment or grass shrimp. Similarly, bottlenose dolphins were also found to contain non-racemic quantities of PCBs 91, 136, 174, 176, and 183. Non-racemic EFs in these biota were likely a result of both uptake of non-racemic proportions of PCBs from the diet and enantioselective biotransformation. [Copyright &y& Elsevier]

The article presents a study which seeks to investigate the relationship between reef types and fish assemblage. The study was conducted at the Gray's National Marine Sanctuary in Georgia. It is noted that the investigators selected flat live bottom for the field survey on fish community assessment and benthic assessment. The result using multivariate analyses showed that two fish assemblages were associated with several types of ledges. The types of ledges include ledges that were tall and heavily colonized with invertebrates and ledges that are smaller in area and does not have undercuts.

Gray’s Reef National Marine Sanctuary (GRNMS) is an increasingly popular site for recreational fishing and diving in the South Atlantic Bight (SAB). As a result, there has been heightened concern about potential accumulation of marine debris and its consequent effects on sanctuary resources. Field surveys were conducted at GRNMS in 2004 and 2005 to provide a spatially comprehensive characterization of benthic communities and to quantify the distribution and abundance of marine debris in relation to bottom features. The spatial distribution of debris was concentrated in the center of the sanctuary and was most frequently associated with ledges rather than other bottom types. On ledges, the presence and abundance of debris was significantly related to observed boating activity and physiographic features including ledge height, ledge area, and percent cover of benthic organisms. The results from this study will aid managers in optimizing cleanup efforts and long-term monitoring of debris accumulation patterns at GRNMS and other hard bottom areas in the SAB. [Copyright &y& Elsevier]

Benthic maps provide the spatial framework for many science and management activities in coastal areas such as identification and protection of fish distributions and associated habitat as well as for monitoring changes in benthos and fish communities. To meet this need at Gray's Reef National Marine Sanctuary off the Georgia, U.S.A., coast, we created fine-scale benthic maps by visual interpretation of sonar imagery within a geographic information system. The major bottom types in the sanctuary fiat sand, rippled sand, hard bottom that is sparsely colonized with sessile invertebrates, and densely colonized hard bottom—were delineated through combined analysis of backscatter from side-scan sonar, bathymetry from multibeam sonar, scuba surveys, and video transects. Maps showed that unconsolidated sediments cover 75% of the bottom of this region; 8% occurs as fiat sand plains with obvious burrowing and reworking of surface material by mobile benthic invertebrates, whereas 67% occurs as rippled sand without such fauna. The rest of the sanctuary consists of limestone bottom in two types of formations; either fiat, sparsely colonized regions (25% of the sanctuary's total area) or as vertical ledges that are densely colonized with a diverse fauna of sessile invertebrates («1%). Despite their limited area, these 0.5–2-m-tall ledge features harbor the majority of the sanctuary's biodiversity and biomass of both sessile invertebrates as well as ichthyofauna. A modified accuracy assessment procedure was used to account for spatial autocorrelation in the validation data and to separate thematic from positional accuracy. Overall thematic accuracy of maps is 95% for those areas of the map in which thematic accuracy and positional accuracy could be separated (87% of the mapped area). This fine-scale characterization provides a benthic inventory for a marine sanctuary and novel methods for mapping using sonar and accuracy assessment using transects. [ABSTRACT FROM AUTHOR]

Neonatal obstructive jaundice is frequently explained by biliary atresia (BA) or the presence of a choledochal cyst (CC). Cystic biliary atresia (CBA) has been a proposed as a subtype of BA with projected improved outcomes. We aimed to characterize these lesions further. We conducted an Institutional Review Board-approved review of all patients treated for obstructive jaundice at our tertiary children's hospital over 10 years. Over the decade we evaluated 91 children with obstructive jaundice: 13 CBA, 52 BA, and 26 CC. Patients with isolated CBA and BA were diagnosed significantly earlier than those with CC (15.9, 54, and 281 days, respectively; P = 0.0001). There was a significant delay between diagnosis and surgical intervention for patients with CBA compared with BA: 17 days versus 5.7 days (P = 0.004). There was no difference in rate of transplant between CBA and BA (31 vs. 50%; P = 0.35). The time from surgery until transplant was 13.9 and 18.6 months for CBA and BA, respectively (P = 0.62). Although radiographically similar to CC, CBA behaves similarly to isolated BA. Delay in recognition and surgical treatment may affect outcomes and lead to an increased incidence of liver failure. The presence of a cystic biliary malformation in the setting of neonatal jaundice should be regarded as CBA until proven otherwise.

Motivation: New sequencing technologies have accelerated research on prokaryotic genomes and have made genome sequencing operations outside major genome sequencing centers routine. However, no off-the-shelf solution exists for the combined assembly, gene prediction, genome annotation and data presentation necessary to interpret sequencing data. The resulting requirement to invest significant resources into custom informatics support for genome sequencing projects remains a major impediment to the accessibility of high-throughput sequence data., Results: We present a self-contained, automated high-throughput open source genome sequencing and computational genomics pipeline suitable for prokaryotic sequencing projects. The pipeline has been used at the Georgia Institute of Technology and the Centers for Disease Control and Prevention for the analysis of Neisseria meningitidis and Bordetella bronchiseptica genomes. The pipeline is capable of enhanced or manually assisted reference-based assembly using multiple assemblers and modes; gene predictor combining; and functional annotation of genes and gene products. Because every component of the pipeline is executed on a local machine with no need to access resources over the Internet, the pipeline is suitable for projects of a sensitive nature. Annotation of virulence-related features makes the pipeline particularly useful for projects working with pathogenic prokaryotes., Availability and Implementation: The pipeline is licensed under the open-source GNU General Public License and available at the Georgia Tech Neisseria Base (http://nbase.biology.gatech.edu/). The pipeline is implemented with a combination of Perl, Bourne Shell and MySQL and is compatible with Linux and other Unix systems.