3,782 research outputs found
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The Response of a Predatory Fish, Ophiodon elongatus, to a Marine Protected Area: Variation in Diet, Catch Rates, and Size Composition
Marine Protected Areas (MPAs) are a management tool used to protect and sustain many ecologically and economically important fish species from overexploitation by recreational and commercial fishing. Lingcod (Ophiodon elongatus) and some of its prey species, such as rockfish (Sebastes spp.), are species that are protected from fishing in some California MPAs. Lingcod is an apex predator that consumes a variety of fish and invertebrate species. In this study, I sought to assess the effect of an MPA on the abundance, size and diet of Lingcod. I hypothesized that Lingcod in a no-take MPA would be more abundant and larger than Lingcod in an adjacent reference site (REF) that was open to fishing. Furthermore, I hypothesized that diet would differ between Lingcod in caught the MPA and Lingcod in the REF. I collected Lingcod from the Point Buchon State Marine Reserve (MPA) and an adjacent REF site that was open to fishing. I measured, weighed, sexed, and collected stomach contents from Lingcod using the gastric lavage (stomach pumping) technique. Then, I identified prey items from Lingcod stomach contents down to the lowest taxonomic level possible and quantified diet composition by percent by occurrence, percent by number, and percent by mass. Lingcod in the MPA consumed more fish prey items than Lingcod in the REF site. Lingcod in the REF consumed more cephalopod prey items than Lingcod in the MPA. I analyzed the four most common prey items (rockfish, anchovies, flatfish, and octopus) for nutritional content. My data suggest that Lingcod increased in size and abundance in a no-take MPA because they do not suffer from fishing mortality. However, a more nutritious diet could also contribute to a biologically significant advantage for Lingcod in the MPA. To address this would require further research focused on calculating the net energy (gross energy extracted from the prey item minus the energetic costs of handling and digesting the prey item) obtained by Lingcod from consuming different fish and cephalopod prey items. MPAs can be an effective management tool for protecting fish stocks, although, it is important to understand the interspecific interactions between predator and prey species to adaptively mange MPAs and the species that reside within them
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The Relationship Between Student Evaluation of Instruction and Selected Predictors
The study attempted to determine the relationship between student evaluation of instruction and institutional performance ratings with the following predictors: faculty job satisfaction, faculty attitudes toward the evaluation process, faculty attitudes toward factors associated with the evaluation process, and faculty characteristics
Evaluation of Marine Corps Manpower computer simulation model
Marine Corps Manpower Plans and Policy Division, Manpower & Reserve Affairs, is responsible for formulating Marine Corps force manpower plans. Accomplishing this mission requires extensive knowledge of the Human Resource Development Process (HRDP) for controlling future personnel attrition, retention, and accession quantities to ensure appropriate quantities of its various Military Occupational Specialties (MOS) and overall end strength are maintained. To assist their mission, an agent-based computer simulation model was developed in the Java computer language. This thesis investigates that simulation model, titled Manpower Simulation Model (MSM). This thesis provides documentation of MSM's architecture and processes, tests the sensitivity of its inputs through the use of an experimental design, and validates MSM's output measures by calculating the relative error for five successive forecast years for various HRDP categories. This thesis found that MSM's structure and output measurement responses aligned with HRDP practices. With respect to validation, on average the HRDP categories losses and accessions underestimated by 17 and 18 percent, respectively, while gains overestimated by 36 percent. The category promotions generally underestimated, but lessened in magnitude as grade increased. The category retention consistently overestimated for all grades. Lastly, the MSM showed biasness toward retaining Marines over backfilling vacancies through accessions.http://archive.org/details/evaluationofmari1094551688Captain, United States Marine CorpsApproved for public release; distribution is unlimited
Exploring the Hydration Levels of Malosma laurina at Different Elevations on a Man-made Trail
The purpose of this study is to examine the water potential of Malosma laurina at different elevations of a man made trail in the chapparal of the Santa Monica Mountains. Chaparral in the Santa Monica Mountains have been depleted because of human involvement effecting the chaparral ecosystem. Fire breaks and man made trails are a few of the major causes of the rapidly changing ecosystem and continues to cause stress among the plants. We are testing the effect that man made trails have on the water potential of Malosma laurina. This was measured by taking samples of Malosma laurina at different altitudes of the trail. Collecting samples and measuring the water potentials of Malosma laurina at different regions led to conclusions about which Malosma laurina plants have the most, least water potential
Stress-Energy Tensor for the Massless Spin 1/2 Field in Static Black Hole Spacetimes
The stress-energy tensor for the massless spin 1/2 field is numerically
computed outside and on the event horizons of both charged and uncharged static
non-rotating black holes, corresponding to the Schwarzschild,
Reissner-Nordstrom and extreme Reissner-Nordstr\"om solutions of Einstein's
equations. The field is assumed to be in a thermal state at the black hole
temperature. Comparison is made between the numerical results and previous
analytic approximations for the stress-energy tensor in these spacetimes. For
the Schwarzschild (charge zero) solution, it is shown that the stress-energy
differs even in sign from the analytic approximation. For the
Reissner-Nordstrom and extreme Reissner-Nordstrom solutions, divergences
predicted by the analytic approximations are shown not to exist.Comment: 5 pages, 4 figures, additional discussio
An investigation of the degradation of Fluorinated Ethylene Propylene (FEP) copolymer thermal blanketing materials aboard LDEF in the laboratory
Samples of fluorinated ethylene propylene copolymer thermal blanketing material, recovered from the Long Duration Exposure Facility (LDEF), were investigated to determine the nature and the extent of degradation due to exposure to the low-Earth-orbit environment. Samples recovered from the ram-facing direction of LDEF, which received vacuum-ultraviolet (VUV) radiation and atomic-oxygen impingement, and samples from the trailing edge, which received almost exclusively VUV exposure, were investigated by scanning electron microscopy and atomic force microscopy. The most significant result of this investigation was found on samples that received only VUV exposure. These samples possessed a hard, embrittled surface layer that was absent from the atomic-oxygen exposed sample and from unexposed control samples. This surface layer is believed to be responsible for the 'synergistic' effect between VUV and atomic oxygen. Overall, the investigation revealed dramatically different morphologies for the two samples. The sample receiving both atomic-oxygen and VUV exposure was deeply eroded and had a characteristic 'rolling' surface morphology, while the sample that received only VUV exposure showed mild erosion and a surface morphology characterized by sharp high-frequency peaks. The morphologies observed in the LDEF samples, including the embrittled surface layer, were successfully duplicated in the laboratory
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Reprinted Internet Safety Guidelines from the Connecticut Conference of the United Church of Christ
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