Estimation of Standardized Effort in the Heterogeneous Gulf of Mexico Shrimp Fleet

In this paper we estimate nominal and standardized shrimping effort in the Gulf of Mexico for the years 1965 through 1993. We accomplish this by first developing a standardization method (model) and then an expansion method (model). The expansion model estimates nominal days fished for noninterview landings data. The standardization model converts nominal days fished to standard days fished. We then characterize the historical trends of the penaeid shrimp fishery byvessel configuration, relative fishing power, and nominal and standardized effort. Wherever possible, we provide comparison with previous estimates by the National Marine Fisheries Service, NOAA

Case Study of On-Farm Experiments and Farm Management Decision Making

Farm Management,

Perceptions of Assessment in Elementary Physical Education: A Case Study

The purpose of the study was twofold: (a) to examine a teacher\u27s perceptions of attempting to implement assessments aligned with the NASPE standards and (b) to examine students\u27 perceptions of assessment in physical education. Participants were 46 4th grade students and their physical education teacher. Data were collected through a Likert-scale attitude questionnaire, documents and interviews with 27 of the 46 students and their teacher. Questionnaire data were analyzed with descriptive statistics. Interview data were analyzed qualitatively. Results indicated that both teacher and students perceived that the teaching-learning process was enhanced through the process of using assessment aligned with the NASPE standards. Secondly, marginalization of physical education impacted both students\u27 and teacher\u27s perceptions of assessment

ESTIMATED COSTS AND RETURNS FOR CATFISH FARMS WITH RECIRCULATING PONDS ALONG THE UPPER TEXAS COAST

Cost, returns, and economies of scale for small, medium and large catfish farms with recirculating ponds are presented for the upper Texas coast. Internal rates of return are 0.150, 0.183 and 0.219, respectively. Total investment is higher than farms with static ponds but investment per unit production capacity is 7 percent to 16 percent lower. Average total cost per pound is between $0.565 and$0.541, (11 percent –20 percent lower than farms using current technology). These results have implications for regional comparative advantage of catfish production as well as incentive for adoption of new technology in conventional ponds.Aquaculture, Catfish, Economics, Off-flavor, Livestock Production/Industries,

Experimental Analysis and Analytical Modeling of Bridges With and Without Diaphragms

Two prestressed concrete (P/C) I-girder bridges along the coal haul route system of Southeastern Kentucky were constructed with a 50 degree skew angle. One of the bridges has concrete intermediate diaphragms, while the other bridge has no intermediate diaphragms. Bridges of similar design along coal haul routes have experienced unusual concrete spalling at the interface of the diaphragms and the bottom flange of the girders. The purpose of this report is to identify the cause of the damage, and to evaluate the effectiveness of intermediate diaphragms. Experimental static and dynamic field testing was conducted on both bridges. All field tests were completed prior to the opening of the bridges. Once the calibration of the finite element models was completed using the test data, analyses were conducted with actual coal haul truck traffic to investigate load distribution and the cause of the spalling at the diaphragm-girder interface. Based on the results obtained in this research study, a significant advantage in structural response is generally not noted due to the presence of intermediate diaphragms. Although large differences were noted percentage wise between the responses of the two bridges, analyses suggested the bridge without intermediate diaphragms will experience displacements and stresses well within AASHTO and ACI design requirements. Finite element analyses also revealed the cause of concrete spalling witnessed in the diaphragm-girder interface region. The tendency of the girders to separate as the bridge was loaded played a large role in generating high stress concentrations in the interface region. Other mitigating factors were the presence of the diaphragm anchor bars and the fact the bridge is subjected to the overloads of coal trucks. Resolving this problem would in some measure require the removal of the concrete intermediate diaphragm. However, the total elimination of intermediate diaphragms is not recommended since they are required during construction and in the event the deck is to be replaced. The use of temporary steel diaphragms, therefore, is recommended as substitutes for the concrete intermediate diaphragms

Thermodynamic signatures for the existence of Dirac electrons in ZrTe5

We combine transport, magnetization, and torque magnetometry measurements to investigate the electronic structure of ZrTe5 and its evolution with temperature. At fields beyond the quantum limit, we observe a magnetization reversal from paramagnetic to diamagnetic response, which is characteristic of a Dirac semi-metal. We also observe a strong non-linearity in the magnetization that suggests the presence of additional low-lying carriers from other low-energy bands. Finally, we observe a striking sensitivity of the magnetic reversal to temperature that is not readily explained by simple band-structure models, but may be connected to a temperature dependent Lifshitz transition proposed to exist in this material.Comment: 5 pages, 4 figure

The effect of surgical approach on the histology of the femoral head following resurfacing of the hip : analysis of retrieval specimens

Objectives: We aimed to determine the effect of surgical approach on the histology of the femoral head following resurfacing of the hip. Methods: We performed a histological assessment of the bone under the femoral component taken from retrieval specimens of patients having revision surgery following resurfacing of the hip. We compared the number of empty lacunae in specimens from patients who had originally had a posterior surgical approach with the number in patients having alternative surgical approaches. Results: We found a statistically significant increase in the percentage of empty lacunae in retrieval specimens from patients who had the posterior approach compared with other surgical approaches (p < 0.001). Conclusions: This indicates that the vascular compromise that occurs during the posterior surgical approach does have long-term effects on the bone of the femoral head, even if it does not cause overt avascular necrosis

Integration of metabolomics, lipidomics and clinical data using a machine learning method.

BACKGROUND: The recent pandemic of obesity and the metabolic syndrome (MetS) has led to the realisation that new drug targets are needed to either reduce obesity or the subsequent pathophysiological consequences associated with excess weight gain. Certain nuclear hormone receptors (NRs) play a pivotal role in lipid and carbohydrate metabolism and have been highlighted as potential treatments for obesity. This realisation started a search for NR agonists in order to understand and successfully treat MetS and associated conditions such as insulin resistance, dyslipidaemia, hypertension, hypertriglyceridemia, obesity and cardiovascular disease. The most studied NRs for treating metabolic diseases are the peroxisome proliferator-activated receptors (PPARs), PPAR-α, PPAR-γ, and PPAR-δ. However, prolonged PPAR treatment in animal models has led to adverse side effects including increased risk of a number of cancers, but how these receptors change metabolism long term in terms of pathology, despite many beneficial effects shorter term, is not fully understood. In the current study, changes in male Sprague Dawley rat liver caused by dietary treatment with a PPAR-pan (PPAR-α, -γ, and -δ) agonist were profiled by classical toxicology (clinical chemistry) and high throughput metabolomics and lipidomics approaches using mass spectrometry. RESULTS: In order to integrate an extensive set of nine different multivariate metabolic and lipidomics datasets with classical toxicological parameters we developed a hypotheses free, data driven machine learning approach. From the data analysis, we examined how the nine datasets were able to model dose and clinical chemistry results, with the different datasets having very different information content. CONCLUSIONS: We found lipidomics (Direct Infusion-Mass Spectrometry) data the most predictive for different dose responses. In addition, associations with the metabolic and lipidomic data with aspartate amino transaminase (AST), a hepatic leakage enzyme to assess organ damage, and albumin, indicative of altered liver synthetic function, were established. Furthermore, by establishing correlations and network connections between eicosanoids, phospholipids and triacylglycerols, we provide evidence that these lipids function as a key link between inflammatory processes and intermediary metabolism

Barge Traffic on Kentucky Rivers

Kentucky currently has the second longest navigable inland waterway system in the United States. Prior to the design of a bridge at a specific location on a river, a thorough investigation of barge traffic at that location ust be conducted. This report investigates the barge traffic on all navigable waterways in Kentucky. This report provides the data necessary to develop the risk assessment procedures for Kentucky vessel impact design problems in accordance with the AASHTO Guide Specification and Commentary for Vessel Collision Design of Highway Bridges design Method II. Method II is more rigorous to apply than Method I, but it is recommended by the guide specification for most bridges and should lead to more economical designs. A computer program was written to process the database and calculate the probability based length, width, and capacity for each barge category. Additionally, a second computer program was written to calculate the probability based number of barges in a flotilla column and row, and subsequently categorize that flotilla based upon the barge length and width categories designated by the U.S. Army Corps of Engineers. The equivalent static impact loads were then calculated using the probability based flotilla sizes and tonnages. The calculations for the Maysville, KY bridge over the Ohio River are offered as a design example