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This study was conducted to determine how reducing the parasite burden in a definitive host may affect the prevalence in intermediate hosts. Here we used the eyeworm Oxyspirura petrowi and cecal worm Aulonocephalus pennula as model species. Northern bobwhite quail (Colinus virginianus) were provided an anthelmintic medicated feed in wild systems because of convincing evidence that these parasites were suppressing their populations. Eyeworm and cecal worm prevalence were measured in Orthopterans, which act as intermediate hosts, using polymerase chain reaction. Individuals were collected from a control site, a site treated for 2 yr, and a site treated for 5 yr. Orthopteran community composition was significantly different among the sites; however, an interaction between subfamily and site was not significant for the eyeworm. There was a significant reduction in eyeworm-infected Orthopterans on the 5-yr site compared with the other 2, suggesting that treatment of a definitive host may indeed affect the prevalence of eyeworms during other life-cycle stages. There was an interaction between the Orthopteran subfamily and the site for the cecal worm, so results were analyzed within each subfamily. A significant reduction in the prevalence of cecal worms was only found in the Cyrtacanthacridinae subfamily on the 5-yr site when compared with the other sites. However, the greatest prevalence in the Gomphocerinae and Oedipodinae subfamilies across all 3 sites was 4.1%. This indicates an unknown degree of cecal worm host specificity. Therefore, conclusions could not be made through the simple assessment of prevalence. [ABSTRACT FROM AUTHOR]

In this paper, asymptotic normal, approximate F-based and BC a bootstrap inferences are proposed for the stress-strength reliability model P (X < Y) , with the assumption that both samples from the two-parameter Burr type X distribution under Type I and Type II censoring. A simulation study is carried out. There is no clear winner among these methods, asymptotic normal and approximate F-based inference work well for the heavy censoring case when R is small, while BC a bootstrap inference could a good choice when R is large. [ABSTRACT FROM AUTHOR]

This paper presents findings from a side-by-side operational comparison of granular road salt (RS) and MeltDown 20 (MD) deicing chemicals for snow and ice control from the perspective of "the maintenance worker in the truck." The field test site, near Canyon, Texas, was divided into sixteen 305 m (1,000 ft) sections that were either untreated controls or received treatment with RS or MD at nominal Texas Department of Transportation (TxDOT) application rates of 85 kg/lane km (300 lb/lane mile) and 42 kg/lane km (150 lb/lane mile), respectively. Three storms met pre-established criteria for snow accumulation, and field test sections were subject to cycles of plowing, deicing treatment, and slushing. Video and still-image data facilitated estimation of visible pavement, and vehicle-based decelerometer tests measured pavement friction. Overall results showed that granular RS outperformed MD in 5/20 data events (25%) and RS outperformed untreated control in 9/20 data events (45%). In contrast, MD never outperformed RS and outperformed control in only 5/20 data events (25%). Further, TxDOT maintenance management data indicate the operational cost to apply MD (corrosion-inhibited) is 3.5× higher than RS (noninhibited), raising questions about cost-effectiveness given the road, climate, and temperature conditions characteristic of the north Texas latitude. [ABSTRACT FROM AUTHOR]

This paper describes depth-calibrated live-load attenuation for the load rating of reinforced-concrete box culverts using production-simplified models. In-plane depth calibration is accomplished using a production-simplified, two-dimensional, linear-elastic, finite-element, soil-structure interaction model with results compared with those from the recommended direct-stiffness, structural-frame model. Out-of-plane live-load attenuation considers each potential critical section depth rather than the cover soil depth only. The effectiveness of depth calibration is assessed by comparing predicted live-load moments obtained from the models versus measured live-load moments obtained from full-scale culvert load tests. A load rating case study illustrates the potential for improved alignment between load rating and observed performance. Findings show that depth calibration improves current load rating practice by increasing the accuracy and precision of live-load demand predictions, particularly in culvert walls and bottom slabs. Use of the depth-calibrated soil-structure model helps close the disconnect between calculated load rating and observed structural performance by more accurately predicting both the location of the weakest critical section and the live-load magnitude. The depth-calibrated soil-structure model also moves the predicted live load toward more uniform accuracy and precision across all sections. [ABSTRACT FROM AUTHOR]

This paper presents results from a laboratory program of 287 pullout tests of galvanized steel reinforcements used in the construction of mechanically stabilized earth (MSE) walls. Results focus on the evaluation of pullout resistance factors for ribbed steel strip and welded steel grid reinforcement embedded in gravelly backfill. This project used Texas Tech University's large-scale MSE test box with dimensions of and an applied overburden capacity equivalent to 12 m of soil fill. The research design evaluated pullout resistance factors for both ribbed strip and welded grid reinforcements for a variety of independent variables, including overburden pressure, reinforcement length, grid bar size, and grid geometry including both transverse and longitudinal bar spacing. Appropriate statistical analyses were used to interpret the data within the context of published design guidance for inextensible MSE reinforcements. The results show that pullout resistance factors for both ribbed strips and welded grids in properly compacted gravelly backfill are significantly higher than those obtained for reinforcements embedded in sandy backfill, as well as default pullout resistance factors. In addition, the results obtained for welded grids indicate that transverse and longitudinal bar spacing, factors not considered in the current formulation, have significant influence on the pullout resistance capacity. [ABSTRACT FROM AUTHOR]

A model for application to carbon fibrous composites is proposed based on the Burr type X (BurrX) distribution first proposed by Burr (Burr, I.W. (1942). Annals of Mathematical Statistics, 13: 215-222) with an included parameter to account for fiber length. The model is further generalized similar to the generalization of the Weibull proposed by Padgett et al. (Padgett, W.J., Durham, S.D. and Mason, A.M. (1995). Journal of Composite Materials, 29: 1873-1884). Maximum likelihood estimation is briefly discussed, and the model is applied to the single-filament data of Bader and Priest (Bader, M.G. and Priest, A.M. (1982). In: Hayashi, T., Kawata, K. and Umekawa, S. (eds), Progress in Science and Engineering of Composites, pp. 1129-1136. ICCM-IV, Tokyo). [ABSTRACT FROM AUTHOR]

When creating designed experiments, it is not always possible to run the experiment at the exact settings required to maintain orthogonal effects. However, this is not measurement error when precise measurements of the settings can be made once the experiment begins. A comparison is made for a 15-run Box–Behnken design using both the intended design settings and the actual design settings. Variance inflation factors are used to measure the induced collinearity in the effects. Two cutoff values are suggested for use to determine when an effect's variance inflation factor is too large to keep that effect in the model. [ABSTRACT FROM AUTHOR]

The northern bobwhite quail ( Colinus virginianus ) is a popular gamebird in the Rolling Plains Ecoregion of West Texas. However, there has been a population decline in this area over recent decades. Consistent reports indicate a high prevalence of the eyeworm ( Oxyspirura petrowi ) and caecal worm ( Aulonocephalus pennula ), which may be of major influence on the bobwhite population. While research has suggested pathological consequences and genetic relatedness to other pathologically significant parasites, little is known about the influence of climate on these parasites. In this study, we examined whether seasonal temperature and precipitation influences the intensity of these parasites in bobwhite. We also analyzed quantitative PCR results for bobwhite feces and cloacal swabs against temperature and precipitation to identify climatic impacts on parasite reproduction in this region. Multiple linear regression analyses were used for parasite intensity investigation while binary logistic regression analyses were used for parasite reproduction studies. Our analyses suggest that caecal worm intensity, caecal worm reproduction, and eyeworm reproduction are influenced by temperature and precipitation. Temperature data was collected 15, 30, and 60 days prior to the date of collection of individual bobwhite and compared to qPCR results to generate a temperature range that may influence future eyeworm reproduction. This is the first preliminary study investigating climatic influences with predictive statistics on eyeworm and caecal worm infection of northern bobwhite in the Rolling Plains.