Doctoral Recital

List of performers and performances

Comparisons between the squash bug egg parasitoids Ooencyrtus anasae and O. sp. (Hymenoptera: Encyrtidae): development, survival,and sex ratio in relation to temperature

Citation: Tracy, J. L., and J. R. Nechols. 1987. “Comparisons Between the Squash Bug Egg Parasitoids Ooencyrtus Anasae and O. Sp. (Hymenoptera: Encyrtidae): Development, Survival, and Sex Ratio in Relation to Temperature.” Environmental Entomology 16 (6): 1324–29. https://doi.org/10.1093/ee/16.6.1324.Laboratory investigations of the gregarious squash bug egg parasitoids Ooencyrtus anasae and O. n. sp. near anasae (O. sp.) were conducted at 20.8, 23.0, and 26.6°C. In both species, total developmental periods (egg to eclosed adult) were inversely related to temperature. Temperature had no significant influence on survivorship, progeny production, or sex ratio. At each temperature, O. anasae developed and emerged about a day earlier and produced a significantly higher percentage of female progeny (77%) than did O. sp. (60%). Both parasitoids deposited an average of three (2-7) progeny per host. However, O. anasae consistently deposited more female eggs per host than did O. sp. Proportion of females produced per host by O. anasae tended to increase directly with number of hosts parasitized, but no such relationship was observed in O. sp. Total preimaginal survivorship in both parasitoids was about 89%. In O. sp., male progeny that developed without females emerged about a day later at all temperatures and had a lower pharate adult survivorship than did males that developed in hosts with female siblings

Performance of feeder pigs of various grades

Production of feeder pigs has become a major swine enterprise in Tennessee. An increasing number of these pigs are being marketed through organized feeder pig sales where they are sorted according to weight and grade. The grade of a feeder pig is determined by evaluating its logical slaughter potential and its thriftiness. The logical slaughter potential of a thrifty feeder pig is its expected slaughter grade at a market weight of about 220 pounds after a normal feeding period. Therefore, the objective of this experiment was to measure the performance, feed efficiency and carcass characteristics of pigs of various feeder grades. Twenty pigs, weighing 40 to 50 pounds, were randomly selected from each of three graded pens; mixed U.S. No. 1 and U.S. No. 2, U.S. No. 3 and U.S. No. 4; at the Lawrence County Feeder Pig Sale, Lawrenceburg, Tennessee. They were wormed, sprayed for external parasites and fed a 16% protein wheat-supplement ration for 105 days. Average daily gain, during the 105-day finishing period, of pigs graded U.S. No. 1-2, U.S. No. 3, and U.S. No. 4 at weaning (40 to 50 pounds) was 1.67, 1.68 and 1.74 pounds per head per day, respectively. The pigs which were graded U.S. No. 4 as feeders were fatter, slightly shorter, less muscular and graded lower at slaughter than the pigs graded higher, U.S. No. 1 through 3. Average back probe for the three feeder grade groups, U.S. No. 1-2, U.S. No. 3, and U.S. No. 4 was 1.30, 1.33 and 1.53 inches, respectively. The leaner, U.S. No. 1 through No. 3 pigs were more efficient feed converters than the fatter U.S. No. 4 pigs. Pigs graded U.S. No. 4 as feeders tended to grade higher at slaughter. Ten percent of the pigs in this feeder grade were graded U.S. No. 1 at slaughter, 35% were graded U.S. No. 2, 50% graded U.S. No. 3 and only 5% were graded U.S. No. 4. These results indicate that many Tennessee feeder pigs are being place in feeder grades below their potential slaughter grade and genetic potential at feeder pig sales due to poor pre-sale management and nutrition. Ihe response of the No. 4 pigs, especially during the 12-day adjustment period, shows the Tennessee producers have an opportunity, through improved management and nutritional practices, to have a greater percentage of their pigs graded higher as feeders

SPATIAL ECOLOGY AND HABITAT USE OF THE WESTERN MASSASAUGA (SISTRURUS TERGEMINUS) IN NEBRASKA

We used radiotelemetry during 2004 and 2005 to investigate seasonal movements and habitat use and to improve our understanding of how land management practices were affecting Western Massasauga (Sistrurus tergeminus) populations in Nebraska. We found Western Massasaugas to brumate in crayfish burrows 100% of the time, and spring emergence occurred during March - April. The longest movements occurred during May when snakes were moving away from brumation sites to summer habitat, after which movements decreased until a second peak in August. We did not find significant differences between male and female activity area, range length, total distance moved, daily movement, or distance from spring and fall brumation sites. However the core activity range of females was significantly less than that of males. During the active season, grassland habitat was used 75.6% of the time compared to habitats of grassland-shrubs (10.7%), hydrophilic vegetation (9.1%), woodlands (3.1%), and shrublands (1.5%). Identifying variations in a species spatial ecology is important for achieving long-term conservation goals because life history events, resource availability, and land management practices may have an effect on seasonal movements and habitat use. The results of our study demonstrate the need for, and some of the necessary data for, improved land management planning in order to meet conservation needs of the Western Massasauga in Nebraska

Enabling Forbidden Dark Matter

The thermal relic density of dark matter is conventionally set by two-body annihilations. We point out that in many simple models, $3 \to 2$ annihilations can play an important role in determining the relic density over a broad range of model parameters. This occurs when the two-body annihilation is kinematically forbidden, but the $3\to 2$ process is allowed; we call this scenario "Not-Forbidden Dark Matter". We illustrate this mechanism for a vector portal dark matter model, showing that for a dark matter mass of $m_\chi \sim \text{MeV - 10 GeV}$, $3 \to 2$ processes not only lead to the observed relic density, but also imply a self-interaction cross section that can solve the cusp/core problem. This can be accomplished while remaining consistent with stringent CMB constraints on light dark matter, and can potentially be discovered at future direct detection experiments.Comment: 12 pages, 8 figures. Updated to match version to be published in PRD. Minor corrections to the cross sections and the Boltzmann equations have been made. More detailed discussions of the secluded case, the Boltzmann equations and the computation of the cross sections have been include

Help for unemployed borrowers: lessons from the Pennsylvania Homeowners’ Emergency Mortgage Assistance Program

In an environment of high foreclosure rates and distressed housing markets, federal policies are focusing on loan modifications to help delinquent homeowners pay their mortgages. While it is too soon to assess the effectiveness of these modifications, policymakers considering future refinements may gain insight from a more established, state-level enterprise that takes an alternative approach to mortgage relief. The Pennsylvania Homeowners’ Emergency Mortgage Assistance Program provides temporary income support to homeowners unable to pay their mortgage during a spell of unemployment. The program has helped most participants retain their homes while paying off their loans—at a potentially lower cost than that of other relief initiatives.Mortgages ; Unemployment

Random Subset Feature Selection for Ecological Niche Modeling of Wildfire Activity and the Monarch Butterfly

Correlative ecological niche models (ENMs) are essential for investigating distributions of species and natural phenomena via environmental correlates across broad fields, including entomology and pyrogeography featured in this study. Feature (variable) selection is critical for producing more robust ENMs with greater transferability across space and time, but few studies evaluate formal feature selection algorithms (FSAs) for producing higher performance ENMs. Variability of ENMs arising from feature subsets is also seldom represented. A novel FSA is developed and evaluated, the random subset feature selection algorithm (RSFSA). The RSFSA generates an ensemble of higher accuracy ENMs from different feature subsets, producing a feature subset ensemble (FSE). The RSFSA-selected FSEs are novelly used to represent ENM variability. Wildfire activity presence/absence databases for the western US prove ideal for evaluating RSFSA-selected MaxEnt ENMs. The RSFSA was effective in identifying FSEs of 15 of 90 variables with higher accuracy and information content than random FSEs. Selected FSEs were used to identify severe contemporary wildfire deficits and significant future increases in wildfire activity for many ecoregions. Migratory roosting localities of declining eastern North American monarch butterflies (Danaus plexippus) were used to spatially model migratory pathways, comparing RSFSAselected MaxEnt ENMs and kernel density estimate models (KDEMs). The higher information content ENMs best correlated migratory pathways with nectar resources in grasslands. Higher accuracy KDEMs best revealed migratory pathways through less suitable desert environments. Monarch butterfly roadkill data was surveyed for Texas within the main Oklahoma to Mexico Central Funnel migratory pathway. A random FSE of MaxEnt roadkill ENMs was used to estimate a 2-3% loss of migrants to roadkill. Hotspots of roadkill in west Texas and Mexico were recommended for assessing roadkill mitigation to assist in monarch population recovery. The RSFSA effectively produces higher performance ENM FSEs for estimating optimal feature subset sizes, and comparing ENM algorithms and parameters, and environmental scenarios. The RSFSA also performed comparably to expert variable selection, confirming its value in the absence of expert information. The RSFSA should be compared with other FSAs for developing ENMs and in data mining applications across other disciplines, such as image classification and molecular bioinformatics

Factors Influencing Anaerobic Pond Treatment of Meat Packing Waste

The objectives if the research were threefold: 1. To determine the effect of increased kill and loading on an anaerobic pond system treating meat packing wastes. 2. To determine the effect of recirculation in an anaerobic pond system treating meat packing wastes. 3. To determine the insulating effect of a meat waste grease-scum. The extent of the research was limited to the anaerobic system.Samples and records were taken at the MID Packing Company from November 1965 through March 1966. During the first period of sampling, data were collected which made possible an evaluation of the effect of higher kill. Grab samples were collected and analyzed for biochemical oxygen demand (BOD) to suspended solids, volatile acids, and pH. Water meter, temperature, and kill records were obtained at the packing plant. During the second period of sampling similar data were taken which made possible the evaluation of the effect of recirculation. The insulating effect of the grease-scum was determined by temperature records taken throughout the period from November to March

HyperManual a hypermedia construction and browsing system in Smalltalk/V Mac

The process of locating needed information in a paper document is often frustrating and time consuming. The information may be available but, since the basic access method is often linear, the information is not readily available. Hypermedia systems offer a computer-based mechanism that can simplify the search process and increase the ratio of useful information found to time expended. Such systems also support the creation of alternate views on the same data base of information. This thesis describes some current hypertext systems and the overall structure of the HyperManual system. This system includes both the tools needed to create and traverse a web of links within a database of documents, and an environment that supports these link construction and information browsing activities. The system differs from other hypermedia systems in that it provides a variety of modes of access to the documents in a hyperdocument. The HyperManual system was written in Smalltalk/V for the Macintosh