Examining the Effects of a Virtual Character on Learning and Engagement in Serious Games

Virtual characters have been employed for many purposes including interacting with players of serious games, with a purpose to increase engagement. These characters are often embodied conversational agents playing diverse roles, such as demonstrators, guides, teachers or interviewers. Recently, much research has been conducted into properties that affect the realism and plausibility of virtual characters, but it is less clear whether the inclusion of interactive agents in serious applications can enhance a user’s engagement with the application, or indeed increase efficacy. In a first step towards answering these questions, we conducted a study where a Virtual Learning Environment was used to examine the effect of employing a virtual character to deliver a lesso

PERCEPTIONS OF LEAFY SPURGE BY PUBLIC LAND MANAGERS, LOCAL DECISION MAKERS, AND RANCH OPERATORS

A survey of 459 ranchers, 56 local decision makers, and 50 public land managers (565 total) was conducted to evaluate managerial, institutional, and social factors that may affect the rate and extent of implementation of various leafy spurge (Euphorbia esula L.) controls. The study focused on a five-county region in Montana, North Dakota, South Dakota, and Wyoming. The questionnaire focused on weed management in general and specifically on the perceptions and attitudes of ranchers, land managers, and local decision makers who have been directly and indirectly affected by leafy spurge.leafy spurge, weed management, rancher opinion, public land manager opinions., Farm Management, Resource /Energy Economics and Policy,

ECONOMIC ANALYSIS OF CONTROLLING LEAFY SPURGE WITH SHEEP

Leafy spurge (Euphorbia esula L.), a widely established exotic, noxious, perennial weed, is a major threat to rangeland and wildland in the Upper Great Plains. Chemical, biological, and cultural control methods have limitations in their applicability and effectiveness in treating leafy spurge. However, many of the constraints prohibiting the use of herbicides, tillage, and biological controls do not apply to sheep grazing. Sheep grazing, while known to be effective in controlling leafy spurge since the 1930s, has lacked widespread adoption as a leafy spurge control. A deterministic, bioeconomic model, incorporating relationships between sheep grazing and leafy spurge control, grass recovery, and forage use by cattle, was developed to evaluate the economic viability of using sheep to control leafy spurge. Discounted annual control costs were compared to discounted annual control benefits over 5-year, 10-year, and 15-year periods. Various scenarios were developed depicting likely situations involving adopting a sheep enterprise or leasing sheep for leafy spurge control. Situational factors considered included fencing expenses, debt considerations, grazing values, infestation size, infestation canopy cover, rangeland productivity, and flock performance. Two levels of flock profitability, one based on a level of proficiency achieved by sheep ranches and one substantially lower than typically achieved in the sheep industry, represented best-case and worst-case situations, respectively. In the best-case situations, using sheep to control leafy spurge was economical in all of the control scenarios examined. However, in the worst-case situations, economics of using sheep to control leafy spurge were mixed across the scenarios examined. Leafy spurge control with poor sheep management, high fence expense, and unproductive rangeland generally was not economical. However, situations with low fencing costs, moderately productive rangeland, and poor sheep management resulted in less economic loss than no treatment. Although many of the key relationships tying leafy spurge control to grazing benefits remain unquantified, the economics of sheep grazing were positive across many of the scenarios evaluated in this study. Actual returns from leafy spurge control for most ranchers will likely fall between the two extremes examined. As a precaution, careful evaluation using site- and rancher-specific inputs would be recommended before implementing sheep grazing as a leafy spurge control method.Leafy Spurge, Weed Control, Sheep Grazing, Economics, Farm Management, Resource /Energy Economics and Policy,

RANCH OPERATORS' PERCEPTIONS OF LEAFY SPURGE

A survey of 459 ranchers was conducted to evaluate managerial, institutional, and social factors that may affect the rate and extent of implementation of various leafy spurge (Euphorbia esula L.) controls in a five-county region in Montana, North Dakota, South Dakota, and Wyoming. Ranchers returned 187 questionnaires. Weeds were considered a greater problem for ranchers with leafy spurge than for those without leafy spurge; however, even among ranchers with leafy spurge, there was strong agreement that other ranching issues were of greater concern. Over 65 percent of the respondents indicated that weeds on their ranch were a `minor problem.' Leafy spurge was ranked as the most important weed. Nearly 60 percent of ranchers felt that using herbicides, biological agents, and grazing animals on leafy spurge were economical; however, only 25 percent of ranchers with leafy spurge felt those controls were `very effective.' A majority of ranchers with leafy spurge indicated plans to treat their infestations with herbicides and biological agents in the future. Reasons for not using various leafy spurge controls fell into environmental, educational, and financial categories. Ranchers depend heavily on their county extension agents and local weed control officers for information on weed control. Information on the effectiveness and economics of various controls was most requested by ranchers. The responses of ranchers to various statements on weed and range management indicated that ranchers, as a group, are generally very concerned about weeds in rangeland. Respondents generally felt it makes economic sense to control weeds in rangeland, and felt very strongly that not enough was being done to control weeds on public land. Ranchers realize the difficulty in controlling leafy spurge, but indicated they are still planning on fighting the weed in the future. Financial and educational constraints to adopting and using leafy spurge controls could be abated through university and governmental educational programs and through cost-share or other financial assistance.leafy spurge, control, rancher opinion, Farm Management, Resource /Energy Economics and Policy,

FEASIBILITY OF A SHEEP COOPERATIVE FOR GRAZING LEAFY SPURGE

This report presents an economic feasibility study of a 5,000 head, cooperatively owned, sheep operation for leafy spurge control. The objectives were 1) determine the return on investment of the cooperative, 2) determine the proposed structure of the cooperative, and 3) ascertain the amount of capital investment required by members in the cooperative. Three sheep flock management alternatives were initially considered for the cooperative. These were 1) winter lambing, 2) spring lambing, and 3) fall lambing. The fall lambing scenario was determined to be infeasible because of logistics associated with gathering and transportation of pregnant ewes and lack of grazing pressure on leafy spurge throughout the grazing season. The total capital investment per ewe for the winter lambing scenario was more than the spring lambing scenario - - $301 and$216, respectively. The expected net income generated by the winter lambing scenario was negative. The minimum break-even lamb selling price or lambs sold per ewe for the winter lambing scenario was $84.10/cwt and 1.33, respectively. The spring lambing scenario returned$124,000 annually. The minimum breakeven lamb selling price or lambs sold per ewe for the spring lambing scenario was $59.51/cwt and 0.94, respectively. The expected return on investment (50% equity) for cooperative members with the spring lambing scenario, assuming a 50-acre leafy spurge infestation in a 100-acre pasture and new fence, was 16 percent (stocking rate of 1 ewe and lambs per acre of leafy spurge). While these returns are not a guarantee of success for the spring lambing alternative, they do provide an indication of the potential that such a cooperative may have.Leafy Spurge, Cooperative, Weed Control, Sheep Grazing, Economics, Farm Management, Resource /Energy Economics and Policy, Agribusiness,

The Effects of the Transition from Pre-nursing to Nursing on Mental Health

Mental health is an ever-growing crisis among adolescents and young adults, with suicide as second leading cause of death and the number of those negatively affected continually on the rise. Transitions are one of the major stressors prevalent among these age groups, placing individuals at risk for mental health deficits. This quantitative voluntary response comparative study assesses the transitional mental health of pre-nursing students and students in the nursing program at East Tennessee State University. Emailed to all with a declared major of pre-nursing or nursing, this study measured mental health using evidenced based assessment tools. The PHQ-9 for depression and the GAD-7 for anxiety, along with additional demographic information and mental health service usage questions, was sent to and completed by participants. A total of n = 173 responses were received. Of these responses n = 99 or 57.2 percent were nursing students, a participation rate of 9.6 percent, and n = 74 or 42.8 percent were pre-nursing students. The research revealed that depression and anxiety scores were above the cutoff for moderate depression and anxiety in both groups, as well as identified a deficit in availability of mental health resources, with over 10 percent of students unable to access counseling or psychiatric services. Contraindicatory to literature, which predicted improving mental health in the progression through university studies, this study reveals a variable and even worsening trajectory of mental health as students transition into the nursing program and progressed through college

Broadband Records of Earthquakes in Deep Gold Mines and a Comparison with Results from SAFOD, California

For one week during September 2007, we deployed a temporary network of field recorders and accelerometers at four sites within two deep, seismically active mines. The ground-motion data, recorded at 200 samples/sec, are well suited to determining source and ground-motion parameters for the mining-induced earthquakes within and adjacent to our network. Four earthquakes with magnitudes close to 2 were recorded with high signal/noise at all four sites. Analysis of seismic moments and peak velocities, in conjunction with the results of laboratory stick-slip friction experiments, were used to estimate source processes that are key to understanding source physics and to assessing underground seismic hazard. The maximum displacements on the rupture surfaces can be estimated from the parameter Rv, where v is the peak ground velocity at a given recording site, and R is the hypocentral distance. For each earthquake, the maximum slip and seismic moment can be combined with results from laboratory friction experiments to estimate the maximum slip rate within the rupture zone. Analysis of the four M 2 earthquakes recorded during our deployment and one of special interest recorded by the in-mine seismic network in 2004 revealed maximum slips ranging from 4 to 27 mm and maximum slip rates from 1.1 to 6:3 m=sec. Applying the same analyses to an M 2.1 earthquake within a cluster of repeating earthquakes near the San Andreas Fault Observatory at Depth site, California, yielded similar results for maximum slip and slip rate, 14 mm and 4:0 m=sec

Ultrahigh Bandwidth Spin Noise Spectroscopy: Detection of Large g-Factor Fluctuations in Highly n-Doped GaAs

We advance all optical spin noise spectroscopy (SNS) in semiconductors to detection bandwidths of several hundred gigahertz by employing an ingenious scheme of pulse trains from ultrafast laser oscillators as an optical probe. The ultrafast SNS technique avoids the need for optical pumping and enables nearly perturbation free measurements of extremely short spin dephasing times. We employ the technique to highly n-doped bulk GaAs where magnetic field dependent measurements show unexpected large g-factor fluctuations. Calculations suggest that such large g-factor fluctuations do not necessarily result from extrinsic sample variations but are intrinsically present in every doped semiconductor due to the stochastic nature of the dopant distribution.Comment: 5 pages, 3 figure

Low genetic diversity in Polish populations of sibling ant species: Lasius niger (L.) and Lasius platythorax Seifert (Hymenoptera, Formicidae)

We present preliminary data on mitochondrial DNA diversity within and among populations of the ants Lasius niger and Lasius platythorax in Poland. Phylogenetic analysis based on the mitochondrial DNA markers: cytochrome c oxidase subunit I (cox1) and 16S ribosomal RNA (16S rRNA) confirms the species status of L. niger and L. platythorax. Intraspecific variability is low in both species, which might be a result of severe bottlenecks and rapid postglacial expansion into Central Europe