3,703 research outputs found
ECOLOGICAL RELEASE OF AN EXOTIC SPECIES UPON SUPPRESSION OF ITS INVASIVE PREDATOR: A FIVE-YEAR CASE STUDY, WITH NOTES ON OTHER SPECIES, AND THE LIFE HISTORY OF THE MEDITERRANEAN GECKO, HEMIDACTYLUS TURCICUS
Ecological release allows a species to expand beyond its currently occupied niche upon removal of a limiting mechanism such as a predator or competitor. Unfortunately, these interactions between exotic and invasive organisms are relatively unknown. We examine how a small-scale, intensive Red Fire Ant (Solenopsis invicta) eradication program may influence the herpetological and formicid community on a 1.85 ha plot in northeast Texas. Red Fire Ant mounds were individually treated with a series of pesticides in 2005, with follow up treatments in 2006 and 2007. Populations of Red Fire Ants, other ant species, reptiles, and amphibians were monitored throughout the study. Other ant species showed signs of recovery after two years of Red Fire Ant suppression. Although reptile and amphibian diversity increased during the study, only populations of the Mediterranean Gecko (Hemidactylus turcicus) showed a dramatic response. The removal of Red Fire Ants provided this exotic Gecko with the opportunity to proliferate. The potential for these kinds of unexpected responses must be considered when removing introduced species from communities containing multiple exotic and potentially invasive organisms
Bilateral Diaphyseal Chondrodysplasia and Polymorphic Osteodysplasia of the Tibiofibulas in a Southern Leopard Frog, Lithobates sphenocephalus (Amphibia: Anura: Ranidae)
Much attention has been focused on limb malformations in anurans following the startling discovery of major limb deformities in Northern Leopard Frogs (Rana pipiens) in Minnesota in 1995. The numerous causes for these malformations can be attributed to a number of natural phenomena, or they can be considered as being manmade. In the present study, we report on a previously undescribed type of limb abnormality in a single individual of the Southern Leopard Frog (Lithobates sphenocephalus) from Arkansas. Histological examination of left tibiofibula revealed a complete disruption of the normal diaphyseal bone structure in this adult frog. The tibiofibula was separated into two poorly ossified and mostly fragmented bony shaft regions on opposite sides of the bone lesion. These peripheral segments of compact bone were surrounded by hypertrophic regions of hyaline cartilage intermingled with complexes of dysplastic bone. We observed three major polymorphic bone aggregates. The overall design of these osteogenic regions can best be described as an arachnoid-like patchwork of numerous pockets, channels, spaces, and nodules separated by trabeculae containing a matrix embedded with subperiosteal bone cells. At present, we are unaware of any environmental conditions that could account for the osteochondrous dysplasia in our specimen. Moreover, the remarkable bilateral placement of the 2 lesions in our specimen suggests the possibly of a genetic factor leading to a pairing of hindlimb developmental anomalies during embryonic bone growth in our specimen
Extending Human-Robot Relationships Based in Music With Virtual Presence
Social relationships between humans and robots require both long term engagement and a feeling of believability or social presence toward the robot. It is our contention that music can provide the extended engagement that other open-ended interaction studies have failed to do, also, that in combination with the engaging musical interaction, the addition of simulated social behaviors is necessary to trigger this sense of believability or social presence. Building on previous studies with our robot drummer Mortimer that show including social behaviors can increase engagement and social presence, we present the results of a longitudinal study investigating the effect of extending weekly collocated musical improvisation sessions by making Mortimer an active member of the participant's virtual social network. Although, we found the effects of extending the relationship into the virtual world were less pronounced than results we have previously found by adding social modalities to human-robot musical interaction, interesting questions are raised about the interpretation of our automated behavioral metrics across different contexts. Further, we found repeated results of increasingly uninteruppted playing and notable differences in responses to online posts by Mortimer and posts by participant's human friends
Deep level transient spectroscopy study for the development of ion-implanted silicon field-effect transistors for spin-dependent transport
A deep level transient spectroscopy (DLTS) study of defects created by
low-fluence, low-energy ion implantation for development of ion-implanted
silicon field-effect transistors for spin-dependent transport experiments is
presented. Standard annealing strategies are considered to activate the
implanted dopants and repair the implantation damage in test
metal-oxide-semiconductor (MOS) capacitors. Fixed oxide charge, interface
trapped charge and the role of minority carriers in DLTS are investigated. A
furnace anneal at 950 C was found to activate the dopants but did not
repair the implantation damage as efficiently as a 1000 C rapid
thermal anneal. No evidence of bulk traps was observed after either of these
anneals. The ion- implanted spin-dependent transport device is shown to have
expected characteristics using the processing strategy determined in this
study.Comment: 4 pages, 6 figure
Shut Up and Play: A Musical Approach to Engagement and Social Presence in Human Robot Interaction
Curly-Tail Malformity in Hatchlings of the Alligator Snapping Turtle, Macroclemys temminckii (Testudines: Chelydridae) in Arkansas
Universal schema for entity type prediction
Categorizing entities by their types is useful in many applications, including knowledge base construction, relation extraction and query intent prediction. Fine-grained entity type ontologies are especially valuable, but typically difficult to design because of unavoidable quandaries about level of detail and boundary cases. Automatically classifying entities by type is challenging as well, usually involving hand-labeling data and training a supervised predictor. This paper presents a universal schema approach to fine-grained entity type prediction. The set of types is taken as the union of textual surface patterns (e.g. appositives) and pre-defined types from available databases (e.g. Freebase) - yielding not tens or hundreds of types, but more than ten thousands of entity types, such as financier, criminologist, and musical trio. We robustly learn mutual implication among this large union by learning latent vector embeddings from probabilistic matrix factorization, thus avoiding the need for hand-labeled data. Experimental results demonstrate more than 30% reduction in error versus a traditional classification approach on predicting fine-grained entities types. © 2013 ACM
Vocabulary sophistication in first-year composition assignments
This is the author accepted manuscript. The final version is available from John Benjamins Publishing via the DOI in this record.Recently-developed tools which quickly and reliably quantify vocabulary use on a range of
measures open up new possibilities for understanding the construct of vocabulary
sophistication. To take this work forward, we need to understand how these different
measures relate to each other and to human readers' perceptions of texts. This study applied
356 quantitative measures of vocabulary use generated by an automated vocabulary analysis
tool (Kyle & Crossley, 2014) to a large corpus of assignments written for First Year
Composition courses at a university in the United States. Results suggest that the majority of
measures can be reduced to a much smaller set without substantial loss of information.
However, distinctions need to be retained between measures based on content vs. function
words and on different measures of collocational strength. Overall, correlations with grades
are reliable but weak
Burden of Proof and Choice of Forum in Tax Litigation
Since the burden of proof may be a decisive factor in tax litigation, it is important that the taxpayer be aware of the different rules in the various forums to which he may take a tax controversy, and it is essential that those rules operate fairly and consistently to enable the taxpayer to choose his forum intelligently. It is the purpose of this article to examine the burden of proof in tax litigation as it affects the choice of forum problem
- …