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Purpose: The NEO-FFI is an extensively used instrument that has been used to identify personality differences between those who stutter and matched controls or group norms. The goal of this study was to use the NEO-FFI to implicitly capture and quantify self-stigma related to personality in persons who stutter (PWS)., Methods: Thirty PWS completed the NEO-FFI twice; once as themselves and once while mentalizing (using theory of mind) to respond as though they did not stutter and had never stuttered, thus comparing their true personality to their perceived personality if they were fluent speakers. Compared to their true personalities, PWS perceived their fluent counterparts to be significantly less neurotic and more extroverted., Results: The differences observed are somewhat analogous, though considerably larger in magnitude than personality differences that have previously been reported when comparing PWS to fluent controls or norms. Differences were interpreted to be due to "contrast effects" influencing the comparison. That is, PWS cognitively separated themselves from their fluent counterparts, seeing their true selves in a negative light compared to their fluent counterparts. This "us" vs. "them" separation is considered evidence of self-stigma related to personality in PWS., Conclusions: The finding that the perceived differences were in the domains of Neuroticism and Extraversion is consistent with prevailing stereotypes about PWS and exemplifies how public stigma can become internalized. Clinical implications are discussed with respect to how similar theory of mind/social comparison exercises can be used in cognitive behavioral therapy to help identify and restructure negative thoughts and beliefs about stuttering.

Consumers consider beef color to be an indicator of freshness and therefore it is a major factor when purchasing beef. The ideal conditions for maintaining color throughout retail display following frozen storage have yet to be well established. Therefore, the objective of this study was to determine the effects of myoglobin oxygenation levels (especially high oxygenation) during freezing on color stability of thawed steaks during retail display (RD) and to determine the impact that frozen storage duration, aging, and packaging films have on meat color after thawing under RD conditions. USDA Choice strip loins (n = 36) were aged for 4 or 20 d. Steaks were randomly assigned to a myoglobin oxygenation level [deoxymyoglobin (DeOxy; packaged within 3 min), oxygenation (Oxy; oxygenated in air for 30 min), or high oxygenation (HiOxy; packaged for 24 h in 80% O 2 )]. Steaks were then vacuum packaged in oxygen permeable or impermeable film and immediately frozen (-10 °C). Following either 0, 2, 4, or 6 months of frozen storage at -5 °C, steaks were removed from the packaging and immediately placed under simulated RD conditions for 7 d. During RD, instrumental color and subjective color were measured every day after the initial 24 h thaw period. Steaks were analyzed for instrumental color (L*, a*, b*), a*:b* ratio, percentage oxymyoglobin, metmyoglobin, and deoxymyoglobin, delta E, redness ratio, subjective discoloration, and lipid oxidation. For all days of RD, steaks that were frozen for 0 months had higher a* values (greater redness) than steaks frozen for 6 months which typically had the lowest a* values (P < .0001). HiOxy steaks frozen for 6 months had the lowest amounts of percentage oxymyoglobin than all other frozen storage periods and myoglobin oxygenation levels on days 4-7 of RD (P < .05). The HiOxy steaks frozen for 4 and 6 months had higher percentage metmyoglobin than DeOxy and Oxy, regardless of packaging (P < .05). Delta E, discoloration, and lipid oxidation were greatest for HiOxy steaks compared to Oxy and DeOxy (P < .05). Extended storage brought about detrimental color effects for all differing levels of myoglobin oxygenation. The HiOxy steaks through the first few days of RD and frozen for under 6 months provided had bright cherry red color, similar to that of DeOxy and Oxy. However, with extended frozen storage and RD, HiOxy steaks had worse color characteristics (more discoloration) than the other myoglobin oxygenation levels., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this study, Plackett-Burman and central composite designs were applied to improve polyhydroxybutyrate (PHB) production from alkaline pretreatment liquor (APL) by Cupriavidus necator DSM 545 using a supplement system consisting of oxidative enzymes (laccase, aryl alcohol oxidase (AAO)), mediators (ABTS, HOBT), DMSO, silica nanoparticle Aerosol R816 and surfactant Tween 80. First, screening experiments under Plackett-Burman design showed R816, ABTS and Tween 80 could significantly enhance PHB production. Additional experiments showed that HOBT and DMSO could be removed, and laccase and AAO were needed to remain in the system. Second, a central composite design was applied to obtain the optimum supplemental levels of R816, ABTS and Tween 80. Under optimum conditions, theoretical maximum PHB production (1.9 g/L) was close to experimental PHB production (2.1 g/L). With the supplement system, a 10-fold increase was achieved compared to PHB production (0.2 g/L) without any supplements., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Porcine epidemic diarrhea virus (PEDV) is an enteric disease of swine that has emerged as a worldwide threat to swine herd health and production. Substantial research has been conducted to assess viability of the virus on surfaces of vehicles and equipment, in feed and water, and on production building surfaces, but little is known about the persistence in PEDV-infected carcasses and effective disposal methods thereof. This study was conducted to quantify the persistence of PEDV RNA via quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) at various time-temperature combinations and in infected piglet carcasses subjected to composting. Although this method does not distinguish between infectious and noninfectious virus, it is a rapid and sensitive test to evaluate materials for evidence of virus genome., Results: In the first study, PEDV was suspended in cell culture media at 1 × 10 5 TCID50 per sample (1 mL sample size) and subjected to various time and temperature combinations in triplicate including temperatures of 37, 45, 50, 55, 60, 65, 70 °C and exposure times of 0, 1, 2, 3, 4, 5, 7, and 14 days. At all temperatures, viral RNA copies declined over time, with the decline most marked and rapid at 65 and 70 °C. Detectable RNA did persist throughout the trial in all but the most extreme condition, where two of three samples incubated at 70 °C yielded undetectable viral RNA after 14 days. In the second study, PEDV-infected piglet carcasses were subjected to two cycles of composting lasting 36 and 37 days, respectively, for a total compost time of 73 days. Composting was performed in triplicate windrow sections housed inside biosecure, climate-controlled rooms using insulated bins designed to represent a continuous windrow compost pile. Temperatures reached 35-57 °C for 26 days of cycle 1 and 35-45 °C for 3 days of cycle 2. Samples consisting of carbon material with or without decomposed tissue as available per sample site collected at ten locations throughout the cross-section of each windrow section following the primary and secondary compost cycles yielded no detectable viral RNA., Conclusions: Composting appears to be an effective disposal method for PEDV-infected piglet carcasses under the conditions examined. The combination of time and high temperature of the compost cycle effectively degraded viral RNA in cell culture media that should provide optimum stability. Complex compost material matrices collected from windrow sections yielded undetectable PEDV RNA by qRT-PCR after one 36-day compost cycle despite incomplete decomposition of soft tissue.

Because pools are tested instead of individuals in group testing, this technique is helpful for estimating prevalence in a population or for classifying a large number of individuals into two groups at a low cost. For this reason, group testing is a well-known means of saving costs and producing precise estimates. In this paper, we developed a mixed-effect group testing regression that is useful when the data-collecting process is performed using inverse sampling. This model allows including covariate information at the individual level to incorporate heterogeneity among individuals and identify which covariates are associated with positive individuals. We present an approach to fit this model using maximum likelihood and we performed a simulation study to evaluate the quality of the estimates. Based on the simulation study, we found that the proposed regression method for inverse sampling with group testing produces parameter estimates with low bias when the pre-specified number of positive pools (r) to stop the sampling process is at least 10 and the number of clusters in the sample is also at least 10. We performed an application with real data and we provide an NLMIXED code that researchers can use to implement this method.

Most genomic-enabled prediction models developed so far assume that the response variable is continuous and normally distributed. The exception is the probit model, developed for ordered categorical phenotypes. In statistical applications, because of the easy implementation of the Bayesian probit ordinal regression (BPOR) model, Bayesian logistic ordinal regression (BLOR) is implemented rarely in the context of genomic-enabled prediction [sample size (n) is much smaller than the number of parameters (p)]. For this reason, in this paper we propose a BLOR model using the Pólya-Gamma data augmentation approach that produces a Gibbs sampler with similar full conditional distributions of the BPOR model and with the advantage that the BPOR model is a particular case of the BLOR model. We evaluated the proposed model by using simulation and two real data sets. Results indicate that our BLOR model is a good alternative for analyzing ordinal data in the context of genomic-enabled prediction with the probit or logit link., (Copyright © 2015 Montesinos-López et al.)

Categorical scores for disease susceptibility or resistance often are recorded in plant breeding. The aim of this study was to introduce genomic models for analyzing ordinal characters and to assess the predictive ability of genomic predictions for ordered categorical phenotypes using a threshold model counterpart of the Genomic Best Linear Unbiased Predictor (i.e., TGBLUP). The threshold model was used to relate a hypothetical underlying scale to the outward categorical response. We present an empirical application where a total of nine models, five without interaction and four with genomic × environment interaction (G×E) and genomic additive × additive × environment interaction (G×G×E), were used. We assessed the proposed models using data consisting of 278 maize lines genotyped with 46,347 single-nucleotide polymorphisms and evaluated for disease resistance [with ordinal scores from 1 (no disease) to 5 (complete infection)] in three environments (Colombia, Zimbabwe, and Mexico). Models with G×E captured a sizeable proportion of the total variability, which indicates the importance of introducing interaction to improve prediction accuracy. Relative to models based on main effects only, the models that included G×E achieved 9-14% gains in prediction accuracy; adding additive × additive interactions did not increase prediction accuracy consistently across locations., (Copyright © 2015 Montesinos-López et al.)

Aphanomyces cochlioides and Rhizoctonia solani are important soilborne pathogens causing root diseases that are primary constraints to sugar beet production in Nebraska, Colorado, and Wyoming. These types of diseases are difficult to control because they are often not noticed until substantial damage has already occurred. Efforts to manage them would be more effective if techniques were available that were more predictive than reactive. Therefore, a preplant soil test was developed to estimate the relative pathogen populations in the soil and to predict potential root disease problems later in the growing season. Preplant soil samples collected from fields to be sown with sugar beet were planted with a susceptible cultivar and tests were conducted for 1 month in the greenhouse. A preplant disease index was developed based on the time period during the test that seedlings became infected and was calculated on a 0-to-100 scale. Disease index values were compared with yields obtained from the same fields after harvest. Analysis of data collected for 5 years (2003 to 2007) with analysis of covariance revealed a strong relationship between the preplant disease index values and recoverable sucrose and root yields but not sucrose concentration. Results indicated that, for each unit increase in the preplant disease index, root yield decreased by 0.27 metric tons (270 kg) per hectare (P < 0.05, R 2 = 0.44) and recoverable sucrose decreased by 49 kg/ha (P < 0.05, R 2 = 0.45). We concluded that this preplant soil test can accurately predict root disease potential due to R. solani and A. cochlioides, and has the potential to help producers make effective management decisions in production fields using the index procedure. This soil assay has additionally provided new information on the biology, incidence, and distribution of root pathogens in production fields throughout the Central High Plains.

Recently, confirmed occurrences of persistent bovine viral diarrhea virus (BVDV) infection in North American alpacas have raised concerns about the role of persistently infected (PI) alpacas in transmission of virus among herds, yet only limited pathological descriptions of persistent infections in alpacas have been reported. The objective of this study was to characterize BVDV antigen distribution in 10 PI alpacas of varying age and to compare viral antigen distribution and localization in tissues of PI alpacas with 5 PI calves of varying age. Ocular dysplasia was evident in 1 PI alpaca, constituting the first reported congenital ocular lesion in PI alpacas. Viral antigen was widely distributed in alpaca tissues and was prominent in neurons, endothelial cells, and vascular tunica media myocytes but had limited distribution in lymphoid tissues and moderate distribution in epithelium of several organ systems of alpacas. Macrophages in the alpaca gastrointestinal system submucosa and lymph node medullary sinuses often had prominent labeling. In addition, only 1 alpaca had antigen labeling in the bone marrow in contrast to PI cattle. Labeled cells in calf tissues were more widely distributed, occurring prominently in lymphoid and epithelial tissues. Common features of the 2 host species were widespread antigen labeling and absence of lymphoid depletion.

Though epistasis has long been postulated to have a critical role in genetic regulation of important pathways as well as provide a major source of variation in the process of speciation, the importance of epistasis for genomic selection in the context of plant breeding is still being debated. In this paper, we report the results on the prediction of genetic values with epistatic effects for 280 accessions in the Nebraska Wheat Breeding Program using adaptive mixed least absolute shrinkage and selection operator (LASSO). The development of adaptive mixed LASSO, originally designed for association mapping, for the context of genomic selection is reported. The results show that adaptive mixed LASSO can be successfully applied to the prediction of genetic values while incorporating both marker main effects and epistatic effects. Especially, the prediction accuracy is substantially improved by the inclusion of two-locus epistatic effects (more than onefold in some cases as measured by cross-validation correlation coefficient), which is observed for multiple traits and planting locations. This points to significant potential in using non-additive genetic effects for genomic selection in crop breeding practices.

Background: The group testing method has been proposed for the detection and estimation of genetically modified plants (adventitious presence of unwanted transgenic plants, AP). For binary response variables (presence or absence), group testing is efficient when the prevalence is low, so that estimation, detection, and sample size methods have been developed under the binomial model. However, when the event is rare (low prevalence <0.1), and testing occurs sequentially, inverse (negative) binomial pooled sampling may be preferred., Methodology/principal Findings: This research proposes three sample size procedures (two computational and one analytic) for estimating prevalence using group testing under inverse (negative) binomial sampling. These methods provide the required number of positive pools ([Formula: see text]), given a pool size (k), for estimating the proportion of AP plants using the Dorfman model and inverse (negative) binomial sampling. We give real and simulated examples to show how to apply these methods and the proposed sample-size formula. The Monte Carlo method was used to study the coverage and level of assurance achieved by the proposed sample sizes. An R program to create other scenarios is given in Appendix S2., Conclusions: The three methods ensure precision in the estimated proportion of AP because they guarantee that the width (W) of the confidence interval (CI) will be equal to, or narrower than, the desired width ([Formula: see text]), with a probability of [Formula: see text]. With the Monte Carlo study we found that the computational Wald procedure (method 2) produces the more precise sample size (with coverage and assurance levels very close to nominal values) and that the samples size based on the Clopper-Pearson CI (method 1) is conservative (overestimates the sample size); the analytic Wald sample size method we developed (method 3) sometimes underestimated the optimum number of pools.

Quantitative trait loci (QTLs) mapping often results in data on a number of traits that have well-established causal relationships. Many multi-trait QTL mapping methods that account for correlation among the multiple traits have been developed to improve the statistical power and the precision of QTL parameter estimation. However, none of these methods are capable of incorporating the causal structure among the traits. Consequently, genetic functions of the QTL may not be fully understood. In this paper, we developed a Bayesian multiple QTL mapping method for causally related traits using a mixture structural equation model (SEM), which allows researchers to decompose QTL effects into direct, indirect and total effects. Parameters are estimated based on their marginal posterior distribution. The posterior distributions of parameters are estimated using Markov Chain Monte Carlo methods such as the Gibbs sampler and the Metropolis-Hasting algorithm. The number of QTLs affecting traits is determined by the Bayes factor. The performance of the proposed method is evaluated by simulation study and applied to data from a wheat experiment. Compared with single trait Bayesian analysis, our proposed method not only improved the statistical power of QTL detection, accuracy and precision of parameter estimates but also provided important insight into how genes regulate traits directly and indirectly by fitting a more biologically sensible model.

Quantitative trait loci (QTL) mapping often results in data on a number of traits that have well-established causal relationships. Many multi-trait QTL mapping methods that account for the correlation among multiple traits have been developed to improve the statistical power and the precision of QTL parameter estimation. However, none of these methods are capable of incorporating the causal structure among the traits. Consequently, genetic functions of the QTL may not be fully understood. Structural equation modeling (SEM) allows researchers to explicitly characterize the causal structure among the variables and to decompose effects into direct, indirect, and total effects. In this paper, we developed a multi-trait SEM method of QTL mapping that takes into account the causal relationships among traits related to grain yield. Performance of the proposed method is evaluated by simulation study and applied to data from a wheat experiment. Compared with single trait analysis and the multi-trait least-squares analysis, our multi-trait SEM improves statistical power of QTL detection and provides important insight into how QTLs regulate traits by investigating the direct, indirect, and total QTL effects. The approach also helps build biological models that more realistically reflect the complex relationships among QTL and traits and is more precise and efficient in QTL mapping than single trait analysis.

In this study, thermochemical biomass gasification was performed on a bench-scale fluidized-bed gasifier with steam and air as fluidizing and oxidizing agents. Distillers grains, a non-fermentable byproduct of ethanol production, were used as the biomass feedstock for the gasification. The goal was to investigate the effects of furnace temperature, steam to biomass ratio and equivalence ratio on gas composition, carbon conversion efficiency and energy conversion efficiency of the product gas. The experiments were conducted using a 3x3x3 full factorial design with temperatures of 650, 750 and 850 degrees C, steam to biomass ratios of 0, 7.30 and 14.29 and equivalence ratios of 0.07, 0.15 and 0.29. Gasification temperature was found to be the most influential factor. Increasing the temperature resulted in increases in hydrogen and methane contents, carbon conversion and energy efficiencies. Increasing equivalence ratio decreased the hydrogen content but increased carbon conversion and energy efficiencies. The steam to biomass ratio was optimal in the intermediate levels for maximal carbon conversion and energy efficiencies.

A spline-enhanced ordinary differential equation (ODE) method is proposed for developing a proper parametric kinetic ODE model and is shown to be a useful approach to PK/PD model development. The new method differs substantially from a previously proposed model development approach using a stochastic differential equation (SDE)-based method. In the SDE-based method, a Gaussian diffusion term is introduced into an ODE to quantify the system noise. In our proposed method, we assume an ODE system with form dx/dt = A(t)x + B(t) where B(t) is a nonparametric function vector that is estimated using penalized splines. B(t) is used to construct a quantitative measure of model uncertainty useful for finding the proper model structure for a given data set. By means of two examples with simulated data, we demonstrate that the spline-enhanced ODE method can provide model diagnostics and serve as a basis for systematic model development similar to the SDE-based method. We compare and highlight the differences between the SDE-based and the spline-enhanced ODE methods of model development. We conclude that the spline-enhanced ODE method can be useful for PK/PD modeling since it is based on a relatively uncomplicated estimation algorithm which can be implemented with readily available software, provides numerically stable, robust estimation for many models, is distribution-free and allows for identification and accommodation of model deficiencies due to model misspecification.

Beef knuckles (n = 160) were obtained from source-verified cattle finished on 30% wet distillers grains plus solubles enriched with varying levels of alfalfa hay (4 or 8%), corn silage (6 or 12%), or corn stalks (3 or 6%) based on NDF. Proximate analysis, pH, oxidation-reduction potential, fatty acid composition, and sensory analysis were conducted on the rectus femoris muscle to determine if roughage inclusion, in conjunction with wet distillers grains plus solubles and cattle source, affects beef flavor with particular interest in liver-like off-flavor. Proximate analysis, fat content, and oxidation-reduction potential were unaffected (P ge;0.129) by diet or source. For s.c. adipose tissue, cattle from Nebraska (NE) had greater amounts of MUFA (P = 0.048) and unsaturated fatty acids (P = 0.068) but less SFA (P = 0.065) when compared with cattle from South Dakota. Diet affected s.c. adipose tissue levels of 15:0, 17:0, and n-3 fatty acids in which cattle from NE finished on the low corn stalk diet had (P < or =0.050) lower levels. Cattle from NE had (P < or = 0.049) greater i.m. adipose proportions of 13:0 and CLA. Dietary effects (P < or = 0.050) were observed for i.m. adipose tissue proportions of 16:0, 18:1(n-9), 18:2(n-6), 20:4(n-6), 22:5(n-3), MUFA, PUFA, and n-6 fatty acids. Sensory analysis revealed that cattle from NE were (P < or = 0.023) less juicy and had less bloody notes when compared with cattle from South Dakota. Cattle finished on the low alfalfa diet were (P < or = 0.014) more tender and juicy but had more bloody notes. No (P ge; 0.670) dietary or source effects were noted for liver-like off-flavor. Subcutaneous amounts of 18:2(n-6 trans) (r = -0.17) were inversely related to the incidence of liver-like off-flavor, whereas 20:1(n-9) (r = 0.21), CLA cis-9, trans-11 (r = 0.16) were directly related. Data from this study indicate that type and level of roughage inclusion and cattle source have minimal effects on fatty acid profiles and sensory properties of the musculus rectus femoris. However, individual fatty acids of s.c. and i.m. adipose tissue were significantly correlated with liver-like off-flavor.

There is a dearth of information on pathogen variation within an individual field. In this study, virulence diversity of Uromyces appendiculatus, cause of bean rust, within individual fields was investigated. From six bean fields in the United States, Honduras, Dominican Republic, and South Africa, 380 U. appendiculatus isolates were differentiated into 65 virulence phenotypes on bean lines containing Andean- and Middle American-derived rust resistance genes. Race variation among bean rust isolates from different geographic regions was found, and virulence phenotypes found in fields from tropical and subtropical regions were more virulent and diverse than those found in fields from temperate regions. The variance components between fields was greater than the variance within a field based on mean disease score on 12 differentials but the variance components within a field were greater than the variances between fields based on number of virulence phenotypes. This is the first report that multiple site samples are needed to represent the fungal virulence diversity in a diseased field. In developing sampling plans, the entire cost of sampling one field is higher than the cost of taking more samples; therefore, to estimate virulence diversity variation, we recommend selecting fewer fields and collecting more samples per field.

Beef knuckles (n = 60) were chosen from a population of 328 knuckles to test a selection procedure and determine the potential causes of liver-like off-flavor. In phase I, 2 independent panelists were allowed to smell the aromas or smell and taste samples of cooked beef to determine the presence or absence of the liver-like off-flavor and off-flavor intensity. The panelists tested knuckles from 5 feedlots, but only identified 29 as having an off-flavor. A kappa statistic was generated to assess the level of agreement of the 2 panelists that indicated the panelists moderately or substantially agreed when judgments were based on smell exclusively or smelling and tasting, respectively. Although the agreement was acceptable (kappa = 0.57 and 0.76), there was not enough variation in the liver-like off-flavor and off-flavor intensity for the 2 panelists to detect differences compared with an independent sensory panel. Phase II identified factors that led to the development of the liver-like off-flavor in beef. The M. rectus femoris from knuckles identified from phase I were used. Sensory analysis, proximate composition, heme iron, mineral content, and fatty acid analyses were conducted. Stepwise regression was used to identify factors contributing to the liver-like off-flavor. Specifically, Na, 16:1, cis 18:1(n-7), 20:2(n-6), and 20:3(n-6) fatty acids explained (P = 0.021) 46% of the variation of the liver-like off-flavor. Although previously reported as playing a role in the development of the liver-like off-flavor, iron, heme iron, and pH had no effect in this study.

A serum free medium was developed for the production of recombinant antibody against Botulinum A (BoNTA) using dihydrofolate reductase deficient Chinese Hamster Ovary Cells (CHO-DG44) in suspension culture. An initial control basal medium was prepared, which was similar in composition to HAM's F12: IMDM (1:1) supplemented with insulin, transeferrin, selenium and a lipid mixture. The vitamin concentration of the basal medium was twice that of HAM's F12: IMDM (1:1). CHO-DG44 cells expressing S25 antibody grew from 2 x 10(5) cells to maximum cell density of 1.04 x 10(6) cells/ml after 5 days in this control medium. A central composite design was used to identify optimal levels and interaction among five groups of medium components. These five groups were glutamine, Essential Amino Acids (EAA), Non Essential Amino Acids (NEAA), Insulin, Transferrin, Selenium (ITS), and lipids. Fifty experiments were carried out in four batches, with two controls in each batch. There was little effect of ITS and Lipid concentrations over the range studied, and glutamine concentration showed a strong interaction with EAA. The optimal concentrations of the variables studied were 2.5 mM Glutamine, 7.4 mM (2x) EAA, 1.4 mM (0.5x) NEAA, 1x ITS supplement, 0.7x Lipids supplement. The maximum viable cell density attained in the optimized medium was 1.4 x 10(6) cells/ml, a 35% improvement over the control culture, while the final antibody titer attained was 22 +/- 3.4 mug/mL, a 50% improvement.

To determine sensory preference and value of fresh beef steak differing in aging technique, strip steaks were evaluated by consumers in Denver (n = 132 consumers) and Chicago (n = 141 consumers). Wet-aged Choice strip loins were matched with dry-aged Choice strip loins, whereas wet-aged Prime strip loins were matched with dry-aged Prime strip loins. Dry-aged strip loins were commercially aged in air in a controlled environment for 30 d and vacuum-aged for 7 d during shipping and storage. Wet-aged strip loins were vacuum-packaged and aged for 37 d in a 1 degrees C cooler. Pairs of strip loins were matched to similar Warner-Bratzler shear force values and marbling scores. Twelve sensory evaluation panels (of 12 scheduled panelists each) were conducted over a 3-d period in each city. Individual samples from a pair of steaks were evaluated by the panelists for sensory traits. Bids were placed on the samples after sensory traits were obtained utilizing a variation of the Vickery auction with silent, sealed bids. No significant differences for sensory traits of flavor, juiciness, tenderness, or overall acceptability were detected between wet-aged Choice samples and dry-aged Choice samples. Although wet-aged Choice samples were numerically superior for all sensory traits, consumers placed similar bid values (P = 0.12) on wet- and dry-aged Choice samples ($3.82 per 0.45 kg and $3.57 per 0.45 kg, respectively). Wet-aged Prime samples were rated more desirable (P < 0.001) for flavor, tenderness, and overall acceptability than dry-aged Prime samples. Wet-aged Prime samples were valued at $4.02 per 0.45 kg, whereas dry-aged Prime samples brought $3.58 per 0.45 kg (P = 0.008). Consumers (29.3%) who preferred the dry-aged Choice samples over the wet-aged Choice samples were willing to pay $1.99/0.45 kg more (P < 0.001) for dry-aged samples. The consumers who preferred the wet-aged Choice over the dry-aged Choice samples (39.2%) were willing to pay $1.77/0.45 kg more (P < 0.0001). Consumers who preferred wet-aged Prime over dry-aged Prime samples (45.8%) paid $1.92/0.45 kg more (P < 0.0001). Consumers who preferred dry-aged Prime samples (27.5%) were willing to pay $1.92/0.45 kg more than for the wet-aged Prime samples. Although more consumers preferred wet-aged samples, markets do exist for dry-aged beef, and consumers are willing to pay a premium for this product.

To determine US consumer acceptance and value of beef from various countries, 24 taste panels of consumers (n = 273 consumers) were conducted in Denver and Chicago. Two pairs of strip steaks were evaluated for flavor, juiciness, tenderness, and overall acceptability on eight-point hedonic scales. One pair consisted of an Australian grass-fed strip steak and a domestic strip steak, whereas the other pair included Canadian and domestic strip steaks. The pairs were matched to similar Warner-Bratzler shear values and marbling scores to decrease variation associated with tenderness and juiciness. A variation of the Vickery auction was used to obtain silent, sealed bids on steaks (0.45 kg) from the same strip loins sampled in the taste panel. Consumers gave higher (P < 0.001) scores for flavor, juiciness, tenderness, and overall acceptability for domestic steaks compared with Australian grass-fed steaks. Domestic steaks averaged 3.68/0.45 dollars kg, whereas consumers placed an average value of 2.48/0.45 dollars kg on Australian grass-fed steaks (P < 0.001). Consumers rated Canadian steaks numerically lower for juiciness (P = 0.09) and lower (P < 0.005) for flavor, tenderness, and overall acceptability than domestic samples. Consumers placed an average value of 3.95/0.45 dollars kg for domestic steaks and 3.57/0.45 dollars kg for Canadian steaks (P < 0.01). Consumers (19.0%) who preferred Australian grass-fed steaks over domestic steaks paid 1.38/0.45 dollars kg more (P < 0.001), whereas consumers (29.3%) who favored the Canadian steaks over the domestic steaks paid 1.37/0.45 dollars kg more (P < 0.001) for the Canadian steaks. A majority of US consumers seem to be accustomed to the taste of domestic beef and prefer domestic steaks to beef from Australia grass-fed and Canadian beef.

To determine consumer sensory acceptance and value of beef steaks differing in marbling level (high = upper USDA Choice and low = USDA Select), but similar in Warner-Bratzler shear value, consumers in Chicago and San Francisco (n = 124 per city) evaluated two matched pairs of high- and low-marbled strip steaks, and had the opportunity to participate in a silent, sealed-bid auction to purchase steaks from the same strip loins as the samples. Consumers who purchased steaks also evaluated the steaks when prepared in their homes. Based on overall acceptability ratings, consumers were categorized into three groups: 1) those who consistently found high marbling more acceptable, 2) those who consistently found low marbling more acceptable, and 3) those who were indifferent. Consumers who evaluated at least one high-marbled and one low-marbled sample in their home were included in an evaluation environment analysis (n = 50). High-marbled steaks were rated higher (P < 0.01) in juiciness, flavor, and overall acceptability than low-marbled steaks. In Chicago, consumers tended to bid more (P < 0.10) for high-marbled steaks, whereas consumers in San Francisco did not. Consumers who found high-marbled steaks more acceptable and those who found low-marbled steaks more acceptable were willing to pay more (P < 0.01) for the more acceptable product. Consumers who evaluated high- and low-marbled samples in both the laboratory and home environments rated high- and low-marbled samples similar (P > 0.10) in flavor, juiciness, tenderness and overall acceptability when evaluating the steaks in their homes. In addition, these consumers were willing to pay similar (P > 0.10) amounts for high- and low-marbled samples in both environments. Overall, consumers found high-marbled steaks to be more acceptable than low-marbled steaks in flavor and overall acceptability when tenderness differences were minimized in the laboratory environment. Consumers were willing to pay more for their preference, whether that preference was for high-marbled or low-marbled steaks.

To determine consumer sensory acceptance and value of branded, Argentine (grass-finished, aged 30+ d) and domestic (U.S. grain-finished beef, aged 9 d) strip loins were paired based on similar Warner-Bratzler shear force values (P = 0.34) and similar marbling levels (P = 0.82). Consumers in Chicago, IL, and San Francisco, CA (n = 124 per city), evaluated one pair of Argentine and domestic steaks, and had the opportunity to participate in a silent, sealed-bid auction to purchase steaks matching the taste panel samples. Consumers were categorized into three groups based on overall acceptability ratings: 1) those who found Argentine steaks more acceptable, 2) those who found domestic steaks more acceptable, and 3) those who were indifferent. Consumers rated domestic steaks higher (P < 0.05) in juiciness, tenderness, flavor, and overall acceptability. Consumers in both Chicago and San Francisco were willing to pay more (P < 0.05) for domestic steaks (0.86 dollars and 0.52 dollars per 0.45 kg, respectively). In both cities, consumers who found Argentine samples more acceptable were willing to pay more (P < 0.05) for Argentine steaks (0.74 dollars per 0.45 kg in Chicago and 1.82 dollars per 0.45 kg in San Francisco), and consumers who found domestic samples more acceptable were willing to pay more (P < 0.05) for domestic steaks (1.66 dollars per 0.45 kg in Chicago and 1.34 dollars per 0.45 kg in San Francisco). Consumers who were indifferent were willing to pay similar (P = 0.99) amounts for Argentine and domestic steaks. Although some consumers found Argentine beef more acceptable than domestic beef (19.7 and 16.5% in Chicago and San Francisco, respectively) and were willing to pay more for it, most consumers found domestic beef to be more acceptable (59.0% in Chicago and 61.5% in San Francisco) and were willing to pay more to obtain a more acceptable product.

To determine visual preference and value for fresh beef steaks differing in marbling level and color, consumers in Chicago and San Francisco (n = 124 per city) evaluated two pairs of steaks in a retail case. Steaks differing in marbling level (Modest/Moderate vs. Slight) and color (bright, cherry-red vs. dark red) were purchased at retail stores in each city. Consumers selected their preferred steak in each pair, described their selection criteria, and provided the price they were willing to pay for each of the four steaks. There was a difference in visual preference in each city, with most consumers preferring (P < 0.01) low (Slight) over high (Moderate/Modest) marbling; however, more (P < 0.01) consumers in Chicago (86.7%) preferred low marbling than in San Francisco (67.0%). Selection criteria were categorized into five groups: marbling, fat, color, appearance, and palatability. Marbling was mentioned by 65.4% of consumers who preferred high marbling, whereas 64.9% of consumers who preferred low marbling mentioned fat as a selection criterion. Bright, cherry-red color was preferred by a higher (P < 0.01) percentage of consumers in both Chicago and San Francisco (67.6 and 76.5%, respectively). Color was mentioned both by consumers who preferred bright, cherry-red color (64.8%) and those who preferred dark red color (63.9%). All preference groups were willing to pay more for their preferred steak (P < 0.01), but consumers who preferred low marbling were willing to pay more (P < 0.01) for their preferred steak than consumers who preferred high marbling. Consumers who preferred bright, cherry-red color were willing to pay more (P < 0.01) for their preferred steak than consumers who preferred dark red color. Consumers who preferred low marbling seemed to desire lean products, and consumers who preferred high marbling seemed to desire products with high eating quality. In this study, consumers were willing to pay more to purchase their preferred product; however, most consumers preferred low marbling and bright, cherry-red color.

Populations of 90 Uromyces appendiculatus isolates were collected from throughout the Americas and evaluated for virulence on 19 standard bean rust differentials, and also on 12 landraces of Phaseolus vulgaris from South and Central America. The landrace differentials represented geographical centers of bean domestication. Three groups were observed. Two groups were isolates from centers of bean domestication and a third heterogeneous group comprised isolates from countries in South and Central America. Molecular analysis using random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) was also conducted on these isolates. Cluster analysis of the molecular profiles showed three groups that corresponded to those obtained by virulence tests. These results show a clear differentiation of the pathogen population along similar lines as its host and suggest parallel evolution in the bean rust pathosystem.

Constructed wetlands are widely used all over the world for the treatment of municipal wastewaters, which are characterized by high concentrations of pathogens. The objectives of this study were (1) to study the effect of solar radiation and temperature on the ability of a constructed wetland to reduce the concentration of total coliforms (TC), and (2) to evaluate the relationship between the presence of Salmonella spp. in the outflow and the concentration of TC. The results of this study showed that under Mediterranean environmental conditions, the percentage reduction in coliforms was lower during winter compared to all other seasons. Maximum removal of coliforms was achieved under conditions of high solar radiation and temperature. In addition, solar radiation was found to play a greater role in coliform die-off at low temperatures than at high temperatures. Finally, it was found that the probability of Salmonella spp. appearance in the outflow of the wetland was related to the concentration of TC. The increase in coliform bacteria in the effluents also increased the chances of Salmonella appearance. The risk of Salmonella spp. appearance in the outflow is minimized when the concentration of TC is below 10(2)/100 mL.

Urediniospore isolates of Puccinia triticina were obtained from wheat leaf collections made in three wheat-growing regions in Nebraska in 1997 and in four regions in 1998. Using 16 Thatcher lines that are near-isogenic for leaf rust resistance, 17 virulence phenotypes were found among 121 single uredinial isolates in 1997, and 42 virulence phenotypes were found among 178 isolates in 1998. The most prevalent phenotype in 1997 was MDRR (virulent on Lr1, 3, 3ka, 10, 11, 18, 23, 24, and 30). In 1998, virulence phenotypes MDRR and MDRM (virulent on Lr1, 3, 3ka, 10, 11, 23, 24, and 30) were the most prevalent. In both years, virulence frequency was above 80% to genes Lr1, 3, 3ka, 10, 11, 23, 24, and 30 and below 21% to Lr2a, 17, and 26. Virulence frequency to Lr2c was 37% in 1997 and 22% in 1998. No virulence was found to Lr9, 16, or 21 in either year. New virulence phenotypes were detected in 1998 that were not found in 1997. In 1998, virulence was less frequent on Lr2a, 2c, 3ka, 18, 24, and 26 and more frequent on Lr17 than in 1997.

Objective: To determine the amount of lead ingested in food by means of duplicate diet collections, nutrient intakes, and anthropometric measurements of young children., Design: Once a month for a year, data were collected from 24-hour duplicate diets, hand wipes, a dust index, and anthropometric measurements. Quarterly, venous blood samples were obtained. Thermal ionization spectrometry by means of a lead-205 tracer was used to determine lead present in food, blood, and the hand wipes. A dust index was determined on the basis of observation of dust on surfaces in the home. Anthropometric measurements obtained were height, weight, head circumference, and mid-upper arm circumference., Subjects/setting: Subjects were 21 children, aged 18 to 36 months, who resided in homes located in an urban area with potentially high lead levels., Main Outcomes Measured: Lead contamination in food and on hands, and blood lead values, were determined., Statistical Analysis Performed: Pearson correlation coefficients were used to determine relationships between lead content in food, blood, and hand wipes and growth. Multiple regression analyses examined the effect of food types and dust lead on lead levels in food, and the effect of these variables on head circumference., Results: Mean blood levels were 0.3089 +/- 0.1496 micromol/L; 12 samples contained more than 0.4826 micromol/L. Total intake of lead from food was 4.95 microg/day and ranged from 1.10 to -22.10 microg/day. More than a fourth of the diets collected exceeded 6.00 microg/day. Foods considered home prepared were moderately related to blood lead level, and the dust index and hand wipe lead levels were related to total food lead. Home-handled foods, canned foods, and hand-wipe lead were significant predictors of the lead content in food. A negative relationship was found between head circumference and blood lead level., Applications: Level of lead in food was directly related to hand-wipe lead. This finding underscores the need for dietitians and other health professionals to stress the importance of cleanliness in environments that are potentially lead contaminated. Appropriate hand washing and surface cleaning should be emphasized when preparing and consuming food. The inverse relationship between head circumference and blood lead levels points to the need for additional studies to validate this finding while controlling for other extraneous variables.

Several factors may affect the validity and outcome of urine testing for abused drugs such as amphetamines, barbiturates, benzodiazepines, cannabinoids, cocaine, ethanol, opiates, and phencyclidine. Urine is used for large-scale testing because acquisition of the sample is noninvasive and because most abused drugs can be detected in urine for a reasonable duration after ingestion. Urine testing for drugs of abuse is a two-step process. In the first step, screening assays are used to identify presumably positive specimens. Common screening tests are radioimmunoassays, enzyme immunoassays, fluorescence polarization immunoassay, and thin layer chromatography. Since they may be subject to cross-reactivity, once a possible positive sample has been identified by a preliminary test, a second more specific methodology, gas chromatography with mass spectrometry, is done to confirm the results. Knowledge of the pharmacology and pharmacokinetics of abused drugs affects selection and interpretation of test results.

A 59-week study was conducted to evaluate the impact of adult Mesocyclops longisetus populations on larval mosquito species inhabiting tires. Greater than 90% reduction of number of 1st and 2nd instars was recorded by 4 wk with 90% reduction of number of 3rd and 4th instars after 7 wk. Reduced control was noted with the onset of cooler winter water temperature. Overall. a 52% reduction in the number of 1st and 2nd instars was achieved, and a 57% reduction was noted in number of 3rd- and 4th-instar mosquito larvae. Cooler temperatures resulted in a decline of adult Mesocyclops, which resulted in reduced larval control. Significantly greater numbers of Mesocyclops adults were collected in tires with either new litter or heavy amounts of litter regardless of litter type. Lastly, litter type, either oak leaves or pine needles, did not influence mosquito reduction or abundance of Mesocyclops populations.

Eight 1-day-old gnotobiotic calves were exposed to one of 2 noncytopathic isolates of bovine viral diarrhea virus (ncp-BVDV 7937 and ncp-BVDV 126) and 2 similar calves were not infected and served as controls. Phenotypic analyses of peripheral blood mononuclear leukocytes at 3, 7, and 10 days postinfection (PI), and cell preparations of thymus, Peyer's patch, mesenteric lymph node, spleen, and bone marrow collected at necropsy, 10 days PI, were conducted using flow cytometric techniques on cells stained by an indirect fluorescent antibody assay using monoclonal antibodies specific for mononuclear leukocyte subsets. Significant fluctuations in specific subsets of peripheral blood mononuclear leukocytes were observed in calves exposed to ncp-BVDV 7937 on day 3 PI (cells expressing MHC class II), day 7 PI (B-cells), and day 10 PI (B cells and cells expressing MHCII). Significant phenotypic differences between groups were also detected in cell preparations from Peyer's patch and thymus. Calves exposed to ncp-BVDV 7937 had a significantly higher percentage of B cells than calves exposed to ncp-BVDV 126 and calves not exposed to BVDV. Calves exposed to ncp-BVDV 126 had a significantly higher percentage of CD2 (BoCD2) positive T cells than calves not exposed to BVDV. Fragility of thymic cell preparations was attributed to infection with virus. These results highlight the importance of the tropism of BVDV for cells of the bovine immune system and its role as a significant immunosuppressive agent capable of predisposing affected animals to infection with other agents.

An approach to selection is proposed that is based on the probabilities that a test cultivar outperforms a check by more than an amount d in a future environment. The function that gives these probabilities for all possible values of d is called the reliability function. When d=0, the value of the reliability function is the probability that the test cultivar outperforms the check. The method is illustrated using data from on-farm maize (Zea mays L.) strip test trials grown cooperatively by Pioneer Hi-bred International and farmers. Results indicate that reliability functions are useful for evaluating how test cultivars perform relative to a check across a range of environments since the location, slope and shape of the reliability function may be used to describe a test cultivar's performance, similarity to the check and stability, and identify environments where the test cultivar has performance problems.

Two anaerobic (A1 and A2), 1 selective (S1), and 3 conventional (C1, C2, and C3) transport media formulations were compared for their capacity to maintain the viability of Serpulina (Treponema) hyodysenteriae. Initial experiments compared the recovery of S. hyodysenteriae from pure cultures held in each transport medium for 0.5, 1, 2, 3, 5, and 7 days at -40 C, 4 C, 25 C, and 36 C. Subsequent experiments compared each transport medium for maintenance of S. hyodysenteriae in fecal specimens obtained from experimentally infected pigs after holding for up to 7 days at 25 C. In each experiment, the viability of S. hyodysenteriae in each transport medium incubated at each temperature and for each period was determined by inoculating the transport medium onto either trypticase soy agar with 5% sheep blood or selective BJ agar and incubating at 42 C anaerobically. Viability and fecal flora contamination were evaluated blindly after 2-, 4-, and 6-day incubation periods. At -40 C, recovery of viable S. hyodysenteriae from pure culture did not differ among the transport media from 0.5 to 7 days, and all of the transport media consistently maintained the viability of the spirochetes for 7 days. At 4 C, the anaerobic and selective transport media maintained the viability of pure cultures of S. hyodysenteriae significantly better than did the conventional transport media group at day 7 (P = 0.019). At the same temperature, the anaerobic media maintained viability better than did the conventional media at 5 days (P less than 0.042).(ABSTRACT TRUNCATED AT 250 WORDS)

A major consideration in most plant breeding programs is the development of cultivars that have high probabilities of outperforming the check cultivar in a broad range of environments. Methods are presented for estimating and testing hypotheses regarding these probabilities, which are termed reliabilities. Reliabilities are shown to be directly related to several commonly used stability parameters. Data from international maize yield trials are used to illustrate and evaluate the repeatability of the approach. Results indicate that reliabilities can be useful aids to plant breeders since they (1) are easy to understand and compute, (2) are indices that weigh the importance of the difference in performance relative to stability, and (3) are potentially useful as genetic parameters since they are generally repeatable across randomly sampled sets of environments.

Variation in recombination rate is important to plant breeders since a major objective is to obtain favorable recombinants of linked genes. The ability to increase recombination (R) in circumstances in which favorable and unvavorable genes are linked (Corn Belt x exotic populations) and to decrease recombination when many favorable genes are linked (narrow-based, elite populations) would be of immense value. However, the concept of variation in recombination frequencies between linked genes has received limited attention despite its implications in breeding and genetic linkage studies. Molecular techniques have allowed better estimations of this variation. In this study, attempts were made to characterize: (1) the R values in the Pgm1-Adh1 and Adh1-Phi1 adjacent regions of chromosome 1 and the Idh2-Mdh2 region of chromosome 6 in F2 families of three maize (Zea mays L.) populations; (2) the environmental effect on R values of F2s from two populations. One population, NSO, was a Corn Belt synthetic, and the other two populations, CBMEX3 and CBCAR5, were composites from crosses between Corn Belt and exotic germ-plams.Wide ranges of estimated recombination ([Formula: see text]) values were observed among families in each population for all three chromsomal regions. The distribution of [Formula: see text] values for the Pgm1-Adh1 region showed that the F2 families of each population fell into two broad categories: 0.30-0.50 and 0.02-0.20. No intermediates (0.21-0.29) were found. The distributions were almost normal for the Adh1-Phi1 and the Idh2-Mdh2 regions. It would appear that the major dispersion in the Pgm1-Adh1 region was controlled by the effects of a single gene, while the Adh1-Phi1 and Idh2-Mdh2 regions were only affected by polygenes. No correlation was found between recombination values of the two adjacent regions, indicating that the genes affecting recombination for the Pgm1-Adh1 region may be specific for that region.For the Pgm1-Adh1 region, no differences in [Formula: see text] values were found among the three populations. For the Adh1-Phi1 region, [Formula: see text] frequencies of CBMEX3 and NSO were not significantly different, but both had significantly greater [Formula: see text] values than CBCAR5. For the Idh2-Mdh2 region, CBMEX3 was significantly different from NSO. There were significant differences between some paired F2 families within each population for each chromosome region.No significant differences in response to the two environments were detected in CBMEX3 and NSO for either region in chromosome 1.

In most plant breeding programs, selection of the best commercially suitable cultivars for a target group of environments is based on information obtained from evaluation trials cultivated in a sample of environments. Information on the performance of cultivars collected in a sample of environments can only be approximate and, consequently, selection of the best cultivar involves choosing among cultivars that respond uncertainly in many environments. The agronomic and/or economic value of a cultivar across environments may be considered the general or overall utility of the cultivar. Data from a sample of environments therefore provides only an estimate of any cultivar's overall utility, with the overall goal of selection among all cultivars being the maximization of the expected utility. Within this frame-work, expected utility maximization, an approach to decision making that has been well developed in the disciplines of economics and statistics, can assist the plant breeder in making such decisions. This research was initiated (1) to determine how expected utility maximization might be used to develop indices that are useful for selecting broadly adapted plant cultivars, and (2) to determine how the breeder's preferences might affect choice of the best cultivar. The data used in this research were from USDA Regional Soybean Tests. The results indicated that expected utility maximization, which explicitly incorporates into the selection rule the plant breeder's preferences regarding stability, can be a useful aid in the selection of stable plant cultivars.

1. At thermoneutrality (28 degrees C), CSF Na+:Ca2+ in hens was 61.66; under thermal stress (39 degrees C), it changed to 59.38 (30 min), 62.58 (3 hr), and 52.44 (10 hr); no change in ratio occurred at 15 degrees C. 2. ICV Ouabain and/or EGTA increased body temperature (TR) but not respiration rate (RR) at 39 degrees C. 3. At 28 degrees C, Ouabain decreased, and EGTA increased, TR and RR. 4. Ca2+ may be more critical than Na+ in thermoregulation. 5. Heat stress appears to stimulate Na+-transport mechanisms other than Na+-ATPase. 6. RR appears to be a function of TR, not of ion balance.

Two feeding trials (early and late lactation) were conducted to measure ad libitum forage intake by beef cows from three breed groups of similar mature weight, but with different milk production potential. Twenty-four cow-calf units, eight from each milk production level (low, medium and high) were grouped (two/pen) based on similarity of cow weight and previous weigh-suckle-weigh and calf weaning weight data. Each pair of cow-calf units was confined to separate pens and allowed ad libitum access to chopped native Sandhills meadow hay. Dry matter intake, cow and calf BW and calf milk consumption were determined. Daily DMI (kg/hd) and milk consumption showed a positive linear response (P less than .05) among low, medium and high milk-producing cows. When cow DMI was expressed as g/unit mean cow BW during the trial, both a positive linear (P less than .05) and a quadratic response (P less than .01) expressed the relationship among production levels during early and late lactation. Calf forage intake, birth weight and adjusted 181- and 205-d weaning weight had no linear or quadratic relationship (P greater than .10) to milk production levels. However, June 1 calf weight, actual calf weaning weight and calf rate of gain (birth to weaning) had a positive linear (P less than .07) relationship. Best fit regression models with DMI as the dependent variable were developed for each trial based on R2 and CV values of the potential models. The best fit model (R2 = .94, SE = .33) for early lactation included production level as a class variable with cow BW.75 and calf birth weight as independent variables. The best fit model (R2 = .92, SE = .53) for late lactation included actual weaning weight in addition to the variables used during early lactation.