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To improve college students' skills in resolving workplace conflict, the authors studied the types of workplace conflicts that students encounter with peers or supervisors in part-time or seasonal work and [...]

The blacklegged tick, Ixodes scapularisSay, is the primary vector of several tick-borne pathogens, including those causing Lyme disease and babesiosis, in the eastern United States and active collection methods for this species include dragging or wild animal sampling. Nest boxes targeting mice may be an alternative strategy for the surveillance and collection of immature I. scapularisfeeding on these hosts and would be much safer for animals compared to small mammal trapping. We constructed double-walled insulated nest boxes (DWINs) with collection tubes mounted below the nesting chamber and deployed eleven in southern Wisconsin from June until September of 2020. The DWINs were occupied by Peromyscusspp. and birds (wren species, Troglodytidae family). We collected 192 ticks from collection tubes, all of which were identified as either I. scapularis(95%) or Dermacentor variabilisSay (Acari: Ixodidae) (5%). Only 12% (21/182) and 20% (2/10) of I. scapularisand D. variabiliswere blood-fed, respectively. The high proportion of unfed ticks found in collection tubes may be due to grooming by hosts inside the nest boxes. Alternatively, immature ticks may have climbed trees and entered the DWIN seeking a host. Results suggest that nest boxes could be a tool for finding ticks in areas of low density or at the leading edge of invasion, when small mammal trapping or drag sampling is not feasible.

The therapeutic landscape of chronic myeloid leukemia (CML) has profoundly changed over the past 7 years. Most patients with chronic phase (CP) now have a normal life expectancy. Another goal is achieving a stable deep molecular response (DMR) and discontinuing medication for treatment-free remission (TFR). The European LeukemiaNet convened an expert panel to critically evaluate and update the evidence to achieve these goals since its previous recommendations. First-line treatment is a tyrosine kinase inhibitor (TKI; imatinib brand or generic, dasatinib, nilotinib, and bosutinib are available first-line). Generic imatinib is the cost-effective initial treatment in CP. Various contraindications and side-effects of all TKIs should be considered. Patient risk status at diagnosis should be assessed with the new EUTOS long-term survival (ELTS)-score. Monitoring of response should be done by quantitative polymerase chain reaction whenever possible. A change of treatment is recommended when intolerance cannot be ameliorated or when molecular milestones are not reached. Greater than 10% BCR-ABL1 at 3 months indicates treatment failure when confirmed. Allogeneic transplantation continues to be a therapeutic option particularly for advanced phase CML. TKI treatment should be withheld during pregnancy. Treatment discontinuation may be considered in patients with durable DMR with the goal of achieving TFR.

Reports on the efforts of cosmologists to discover what caused stars to form. Indication that stars did not form for millions of years after the Big Bang; How density fluctuations left over from the Big Bang could have evolved into the first stars; Role of stars in the development of galaxies, quasars, and planets; Study of the early universe through telescope observations of distant galaxies and quasars that emitted their light billions of years ago; Composition of the first stars which were probably massive and very hot. INSET: Overview/The First Stars.

Big data are frequently used in many facets of business and agronomy to enhance knowledge needed to improve operational decisions. Livestock operations collect data of sufficient quantity to perform predictive analytics. Predictive analytics can be defined as a methodology and suite of data evaluation techniques to generate a prediction for specific target outcomes. The objective of this manuscript is to describe the process of using big data and the predictive analytic framework to create tools to drive decisions in livestock production, health, and welfare. The predictive analytic process involves selecting a target variable, managing the data, partitioning the data, then creating algorithms, refining algorithms, and finally comparing accuracy of the created classifiers. The partitioning of the datasets allows model building and refining to occur prior to testing the predictive accuracy of the model with naive data to evaluate overall accuracy. Many different classification algorithms are available for predictive use and testing multiple algorithms can lead to optimal results. Application of a systematic process for predictive analytics using data that is currently collected or that could be collected on livestock operations will facilitate precision animal management through enhanced livestock operational decisions.

Some cattle production experts believe that cow–calf producers should breed replacement heifers (nulliparous cows) before cows (primiparous and multiparous cows), sometimes referred to as providing a heifer lead time (tHL). Our objective was to model the effects different durations of tHL may have on measures of herd productivity, including the percent of the herd cycling before the end of the first 21 d of the breeding season (%C21), the percent of the herd pregnant at pregnancy diagnosis (%PPD), the distribution of pregnancy by 21-d breeding intervals, the kilograms of calf weaned per cow exposed (KPC), and the replacement percentage (%RH), using a deterministic, dynamic systems model of cow–calf production over a 10-yr horizon. We also wished to examine differences in the effect of tHL related to the primiparous duration of postpartum anestrus (dPPAp). The study model examined 6 different dPPApfor primiparous cows (60, 70, 80, 90, 100, or 110 d). The multiparous cow duration of postpartum anestrus was set to 60 d. The breeding season length for nulliparous cows was 63 d, as was the breeding season length for primiparous and multiparous cows. Nulliparous cows were modeled with a tHL of 0, 7, 14, 21, 28, 35, or 42 d. Results are reported for the final breeding season of the 10-yr horizon. Increasing tHL resulted in a greater %C21 for the herd and for primiparous cows. Length of tHL had minimal impact on the %PPD unless the dPPApwas 80 d or greater. For a dPPApof 110 d, a 0 d tHL resulted in the herd having 88.1 %PPD. When tHL was 21 d, the %PPD increased to 93.0%. The KPC was 161.2 kg when the dPPAdwas 110 d and tHL was 0 d and improved to 183.2 kg when tHL was increased to 42 d. The %RH did not vary much unless the dPPApwas 90 d or greater, but increasing tHL resulted in decreased %RH. Based on the model results, increasing tHL improves the production outcomes included in the analysis, but herds with dPPApof 90 d or greater had the greatest degree of improvement. For these herds, approximately two-thirds of the improvement in outcomes by increasing tHL from 0 d to 42 d was realized when tHL was 21 d. Costs are likely incurred when implementing tHL in a breeding management program, and an ideal tHL likely depends on the dPPApof the herd, the expected improvement in productivity, and the costs associated with increasing tHL. Determining the dPPApof a herd could help veterinarians and producers develop optimal herd management strategies.

Asparaginase, which depletes asparagine and glutamine, activates amino-acid stress response. Oxidative stress mediated by excessive reactive oxygen species (ROS) causes enhanced mitochondrial permeabilization and subsequent cell apoptosis and is considered as a plausible mechanism for drug-induced hepatotoxicity, a common toxicity of asparaginase in adults with acute lymphoblastic leukemia (ALL). Studies investigating the pharmacogenetics of asparaginase in ALL are limited and focused on asparaginase-induced allergic reaction common in pediatric patients. Here, we sought to determine a potential association between the variant rs4880 in SOD2gene, a key mitochondrial enzyme that protects cells against ROS, and hepatotoxicity during asparaginase-based therapy in 224 patients enrolled on CALGB-10102, a treatment trial for adults with ALL. We report that the CC genotype of rs4880 is associated with increased hepatotoxicity following asparaginase-based treatment. Thus, rs4880 likely contributes to asparaginase-induced hepatotoxicity, and functional studies investigating this single-nucleotide polymorphism (SNP) are needed to develop therapeutic approaches that mitigate this toxicity.

The duration of postpartum anestrus (dPPA) is important to consider for reproductive performance and efficiency in cow-calf operations. We developed a deterministic, dynamic systems model of cow-calf production over a 10-yr horizon to model the effects that dPPA had on measures of herd productivity, including the percentage of cows cycling before the end of the first 21 d of the breeding season (%C21), the percentage of cows pregnant at pregnancy diagnosis (%PPD), the distribution of pregnancy by 21-d breeding intervals, the kilograms of calf weaned (KW), the kilograms of calf weaned per cow exposed (KPC), and the replacement percentage. A 1,000-animal herd was modeled, with the beginning and ending dates for a 63-d natural service breeding season being the same for eligible replacement heifers (nulliparous cows) and cows (primiparous and multiparous cows). Herds were simulated to have a multiparous cow dPPA of 50, 60, 70, or 80 d, with the dPPA for primiparous cows being set to 50, 60, 70, 80, 90, 100, or 110 d. Only combinations where the primiparous dPPA was greater than or equal to the multiparous dPPA were included, resulting in 22 model herds being simulated in the analysis. All other model parameters were held constant between simulations. In model season 10, the %C21 was 96.2% when the multiparous cow and primiparous cow dPPA was 50 d and was 48.3% when the multiparous cow and primiparous cow dPPA was 80 d. The %PPD in model season 10 for these same herds was 95.1% and 86.0%, respectively. The percentage of the herd becoming pregnant in the first 21 d of the breeding season also differed between these herds (61.8% and 31.3%, respectively). The 10-yr total KW was more than 275,000 kg greater for the herd with a 50-d multiparous cow and primiparous cow dPPA when compared with the herd with the 80-d multiparous and primiparous cow dPPA and had a model season 10 KPC of 180.8 kg compared with 151.4 kg for the longer dPPA. The model results show that both the multiparous cow and primiparous cow dPPA affect herd productivity outcomes and that a dPPA less than 60 d results in improved production outcomes relative to longer dPPA. Veterinarians and producers should consider determining the dPPA to aid in making management decisions to improve reproductive performance of cow-calf herds.

The objective of this project was to identify risk factors associated with the probability of failing to resolve clinical signs of bovine respiratory disease (BRD) after initial antimicrobial treatment. A retrospective data analysis was performed with 194,062 animals treated for BRD with an antimicrobial from 10 U.S. feedlots from 2005 to 2009. A binary variable classified cattle as a treatment failure if they were retreated for BRD or died following an initial BRD treatment. A generalized logistic mixed model was created to evaluate associations of quarter of the year at feedlot arrival, arrival weight, sex, risk classification (high vs. low), days on feed at first BRD treatment, and rectal temperature at first BRD treatment and all 2-way interactions with the probability of first treatment failure for BRD. A total of 64,683 out of 194,062 (33.3%) of cattle initially treated for BRD were classified as treatment failures due to death or retreatment. Multiple 2-way interactions were present. High-risk calves had greater probability of first treatment failure compared with low-risk calves, but this effect was modified by quarter of arrival, days on feed at first treatment, and rectal temperature category. The effect of arrival weight category was modified by days on feed at first treatment of BRD and quarter of arrival for probability of first treatment failure. Multiple arrival and treatment characteristics were associated with the probability of first BRD treatment failure. Knowledge of these factors can lead future prospective studies to improve the prediction of treatment failure and provide baseline results for the industry.

This phrase, whose meaning has been attributed to Peter Drucker, sets the stage for this article, for it highlights the differences between, as he said, 'doing the right things' (effectiveness) […]

The thermodynamic state of star-forming gas determines its fragmentation behavior and thus plays a crucial role in determining the stellar initial mass function (IMF). We address the issue by studying the effects of a piecewise polytropic equation of state (EOS) on the formation of stellar clusters in turbulent, self-gravitating molecular clouds using three-dimensional, smoothed particle hydrodynamics simulations. In these simulations stars form via a process we call gravoturbulent fragmentation, i.e., gravitational fragmentation of turbulent gas. To approximate the results of published predictions of the thermal behavior of collapsing clouds, we increase the polytropic exponent γfrom 0.7 to 1.1 at a critical density nc, which we estimated to be $2.5\times10^5\,\mathrm{cm^{-3}}$. The change of thermodynamic state at ncselects a characteristic mass scale for fragmentation Mch, which we relate to the peak of the observed IMF. A simple scaling argument based on the Jeans mass $M_\mathrm{J}$at the critical density $n_\mathrm{c}$leads to $M_{\mathrm{ch}}\propto n_{\mathrm{c}}^{-0.95}$. We perform simulations with $4.3\times10^4\,\mathrm{cm^{-3}} < n_{\mathrm{c}} < 4.3\times10^7\,\mathrm{cm^{-3}}$to test this scaling argument. Our simulations qualitatively support this hypothesis, but we find a weaker density dependence of $M_{\mathrm{ch}} \propto n_{\mathrm{c}}^{-0.5\pm0.1}$. We also investigate the influence of additional environmental parameters on the IMF. We consider variations in the turbulent driving scheme, and consistently find $M_{\mathrm{J}}$is decreasing with increasing $n_{\mathrm{c}}$. Our investigation generally supports the idea that the distribution of stellar masses depends mainly on the thermodynamic state of the star-forming gas. The thermodynamic state of interstellar gas is a result of the balance between heating and cooling processes, which in turn are determined by fundamental atomic and molecular physics and by chemical abundances. Given the abundances, the derivation of a characteristic stellar mass can thus be based on universal quantities and constants.

The objective of this project was to evaluate the effects of antimicrobials approved for parenteral metaphylactic use in feeder and stocker calves on morbidity and mortality for bovine respiratory disease with the use of a mixed treatment comparison meta-analysis. An initial literature review was conducted in April 2016 through Pubmed, Agricola, and CAB (Commonwealth Agricultural Bureau) for randomized controlled trials for metaphylaxis antimicrobial administered parentally to incoming feedlot or stocker calves within 48 h of arrival. The final list of publications included 29 studies, with a total of 37 trials. There were 8 different metaphylactic antimicrobials. Final event outcomes were categorized into bovine respiratory disease (BRD) morbidity cumulative incidence d 1 to ≤ 60 of the feeding period, BRD morbidity cumulative incidence d 1 to closeout of the feeding period, BRD mortality cumulative incidence d 1 to closeout of the feeding period, and BRD retreatment cumulative incidence morbidity d 1 to closeout of the feeding period. Network meta-analysis combined direct and indirect evidence for all the event outcomes to determine mean odds ratio (OR) with 95% credibility intervals (CrIs) for all metaphylactic antimicrobial comparisons. The “upper tier” treatment arms for morbidity d 1 to ≤ 60 included tulathromycin, gamithromycin, and tilmicosin. For BRD mortality cumulative incidence d 1 to closeout and BRD retreatment morbidity d 1 to closeout, classifying the treatment arms into tiers was not possible due to overlapping 95% CrIs. The results of this project accurately identified differences between metaphylactic antimicrobials, and metaphylactic antimicrobial options appear to offer different outcomes on BRD morbidity and mortality odds in feedlot cattle.

In this prospective phase 2 clinical trial conducted by Cancer and Leukemia Group B (CALGB, now the Alliance), we studied decitabine as maintenance therapy for younger adults with acute myeloid leukemia (AML) who remained in first complete remission (CR1) following intensive induction and consolidation. Given that decitabine is clinically active in AML and with hypomethylating activity distinct from cytotoxic chemotherapy, we hypothesized that 1 year of maintenance therapy would improve disease-free survival (DFS) for AML patients <60 years, who did not receive allogeneic stem cell transplantation in CR1. After blood count recovery from final consolidation, patients received decitabine at 20 mg/m2intravenously daily for 4–5 days, every 6 weeks for eight cycles. One hundred and thirty-four patients received decitabine and 85 (63%) had favorable risk AML. The median number of cycles received was 7 (range: 1–8) and the primary reason for discontinuation was relapse. DFS at 1 year and 3 years was 79% and 54%, respectively. These results are similar to the outcomes in the historical control comprising similar patients treated on recent CALGB trials. Thus, maintenance with decitabine provided no benefit overall. Standard use of decitabine maintenance in younger AML patients in CR1 is not warranted. This trial was registered at www.clinicaltrials.govas NCT00416598.

Appropriate statistical analysis is critical in interpreting results from published literature to answer clinical and management questions. Internal validity is an assessment of whether the study design and statistical analysis are appropriate for the hypotheses and study variables while controlling for bias and confounding. External validity is an assessment of the appropriateness of extrapolation of the study results to other populations. Knowledge about whether treatment or observation groups are truly different is unknown, but studies can be broadly categorized as exploratory or discovery, based on knowledge about previous research, biology, and study design, and this categorization affects interpretation. Confidence intervals, P-values, prediction intervals, credible intervals, and other decision aids are used singly or in combination to provide evidence for the likelihood of a given model but can be interpreted only if the study is internally valid. These decision aids do not test for bias, study design, or the appropriateness of applying study results to other populations dissimilar to the population tested. The biologic and economic importance of the magnitude of difference between treatment groups or observation groups as estimated by the study data and statistical interpretation is important to consider in clinical and management decisions. Statistical results should be interpreted in light of the specific question and production system addressed, the study design, and knowledge about pertinent aspects of biology to appropriately aid decisions.

Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17), leading to the formation of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations, which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, whereas mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large-scale activation of gene expression and reduced in vitro differentiation potential.

In the phase 3 Evaluating Nilotinib Efficacy and Safety in Clinical Trials–Newly Diagnosed Patients (ENESTnd) study, nilotinib resulted in earlier and higher response rates and a lower risk of progression to accelerated phase/blast crisis (AP/BC) than imatinib in patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP). Here, patients’ long-term outcomes in ENESTnd are evaluated after a minimum follow-up of 5 years. By 5 years, more than half of all patients in each nilotinib arm (300 mg twice daily, 54%; 400 mg twice daily, 52%) achieved a molecular response 4.5 (MR4.5; BCR-ABL⩽0.0032% on the International Scale) compared with 31% of patients in the imatinib arm. A benefit of nilotinib was observed across all Sokal risk groups. Overall, safety results remained consistent with those from previous reports. Numerically more cardiovascular events (CVEs) occurred in patients receiving nilotinib vs imatinib, and elevations in blood cholesterol and glucose levels were also more frequent with nilotinib. In contrast to the high mortality rate associated with CML progression, few deaths in any arm were associated with CVEs, infections or pulmonary diseases. These long-term results support the positive benefit-risk profile of frontline nilotinib 300 mg twice daily in patients with CML-CP.

Agricultural operations can pose a threat to the quality of nearby water sources particularly from nitrogen (N) and phosphorus (P) losses following land application of manure. Biochar application to soils has the potential to ameliorate degraded soils and reduce nutrient leaching to groundwater. The effects of amending sand soil columns with hybrid poplar biochar (Populusspp.) made by a slow‐pyrolysis process at 450°C at varying rates (0, 1, 2, and 5% by weight) with repeated dairy manure applications over a 56‐wk period was examined to evaluate the impact to leachate water quality. Increasing levels of biochar decreased cumulative levels of total N (TN) by 21 to 59%, nitrate (NO3–N) by 17 to 46%, and ammonia (NH4–N + NH3–N) by 46 to 90% in leachate but increased cumulative leaching of total P (TP). Overall leachate pH was increased and peak levels of 5‐d biological oxygen demand (BOD5) in leachate after manure application were decreased with increasing levels of biochar amendment. The results from this study indicate that biochar amendments could be effective in reducing nitrogen leaching from soils, though further study is needed to determine practical application in a field setting. Hybrid poplar biochar application to sand can improve leachate water quality.Leachate BOD5reduced with increasing biochar application rate.Total N, NO3–N, and NH4–N were reduced in leachate with increasing biochar application rate.

Phase diagrams are determined by Monte Carlo lattice simulations for idealized symmetric and asymmetric surfactant molecules mixed with single-site “oil” and “water” molecules. At high concentrations (above 20%) of surfactant, the simulations show the self assembly of liquid crystalline phases, including smectic, hexagonal, BCC sphere packings, and Ia3d gyroid cubic phases. The locations of the phases on the diagram for asymmetric surfactants in “water” are shifted relative to those for a symmetric one in a way that favors phases whose surfactant-laden interfaces curve so that the bulkier group is on the convex side of the interface. When the system composition is gradually charged, cylinders of a hexagonal phase are oriented along the 111 direction of the micellar BCC or Ia3d phase into which the cylinders epitaxially transform, with the d-spacing ratios of 1.22 and 2.12, respectively. These and many other aspects of the predicted phase behavior, including the compositions at which transitions among ordered phases occur, compare favorably with experimental observations for nonionic, cationic, anionic, and zwitterionic single-tail surfactants.

Bovine respiratory disease is an economically important syndrome in the beef industry, and diagnostic accuracy is important for optimal disease management. The objective of this study was to determine whether improving diagnostic sensitivity or specificity was of greater economic value at varied levels of respiratory disease prevalence by using Monte Carlo simulation. Existing literature was used to populate model distributions of published sensitivity, specificity, and performance (ADG, carcass weight, yield grade, quality grade, and mortality risk) differences among calves based on clinical respiratory disease status. Data from multiple cattle feeding operations were used to generate true ranges of respiratory disease prevalence and associated mortality. Input variables were combined into a single model that calculated estimated net returns for animals by diagnostic category (true positive, false positive, false negative, and true negative) based on the prevalence, sensitivity, and specificity for each iteration. Net returns for each diagnostic category were multiplied by the proportion of animals in each diagnostic category to determine group profitability. Apparent prevalence was categorized into low (<15%) and high (≥15%) groups. For both apparent prevalence categories, increasing specificity created more rapid, positive change in net returns than increasing sensitivity. Improvement of diagnostic specificity, perhaps through a confirmatory test interpreted in series or pen-level diagnostics, can increase diagnostic value more than improving sensitivity. Mortality risk was the primary driver for net returns. The results from this study are important for determining future research priorities to analyze diagnostic techniques for bovine respiratory disease and provide a novel way for modeling diagnostic tests.

‘Warhorse’ (Reg. No. CV‐1096, PI 670157) hard red winter (HRW) wheat (Triticum aestivumL.) was developed and released by the Montana Agricultural Experiment Station in September 2013. Warhorse is of unknown pedigree, derived from a composite of three topcrosses made to the same F1population in 2000: MT9908//‘Nuplains’/MTS9862; Nuplains/MTS9862//MTW0047; and Nuplains/MTS9862//MTS0028. Warhorse was developed using a modified bulk breeding method and selected as an F5:6headrow. Warhorse was tested under the experimental number MTS0808 from 2008 to 2013 in Montana. Quality was evaluated in multilocation Montana trials since 2008. Warhorse is a solid‐stem, high‐yielding HRW wheat line with medium to high test weight, medium maturity, reduced height (Rht‐B1b), medium to high grain protein, and acceptable milling and baking quality. Warhorse was released for its improved host plant resistance to wheat stem sawfly (Cephus cinctusNort.) conditioned by stem solidness, along with short stature and improved yield potential relative to existing solid‐stem cultivars adapted to Montana.

This clinical trial evaluated the impact of metaphylactic antimicrobial administration 10 d before experimental inoculation with Mannheimia haemolytica(MH) to mitigate pulmonary lesions. Thirty-three crossbreed heifers were procured as a single group and were randomly allocated to 1 of 3 blocks and to treatment, tildipirosin (ZUP; 4 mg/kg) or tulathromycin (DRX; 2.5 mg/kg) or saline (SAL; 1 mL/45.5 kg), within block on arrival at Kansas State University. All trial procedures were staggered by 7-d intervals for each block, resulting in all animals within a block receiving treatment, challenge, and necropsy on the same dates. Heifers within each block received an endoscopic MH challenge 10 d following treatment administration (d 0) and were housed in individual indoor stalls for 3 d postchallenge. Clinical illness scores (CIS), respiration quality scores, appetite scores, and injection site reactions were recorded on all animals from d 0 through d 13. Rectal temperatures were measured once daily on all animals from d 8 through d 13. Heifers were necropsied, and lung lesions were evaluated on d 13. Lung lesion data were evaluated using nonparametric methods (Kruskall-Wallis), and standard least squares models were used to evaluate the remaining variables. The pulmonary lesion scores (percentage of affected lung) ranged from 3.3% to 39.8% for all heifers with 92% (11/12) of ZUP-treated heifers having <10% lesions. Tildipirosin-treated heifers had lower (P< 0.05) lung lesion scores when compared with DRX- and SAL-treated heifers. Lung weight expressed as a percentage of BW was lower (P< 0.05) in ZUP heifers compared to DRX- and SAL-treated heifers. The probability of receiving abnormal CIS, appetite scores, and respiratory scores was lower (P< 0.05) in ZUP-treated heifers compared to DRX- and SAL-treated animals. This study showed that heifers treated with tildipirosin 10 d before MH challenge have less pulmonary damage and fewer clinical signs of illness compared to heifers treated with DRX or SAL.

Exposure to particulates containing metals and metal fumes (PCMMF) is a potential concern in ore refining and smelting. Some metals of primary interest are arsenic, cadmium, copper and lead, which have been linked to various adverse health effects. The current National Institute for Occupational Safety and Health (NIOSH) sampling method for metals in particulates requires the use of a filter, precision airflow pump and laboratory analysis. A major concern with this method is the one-to-two weeks’ wait before laboratory results are available for use in determining if additional controls are needed to assure adequate exposure protection for workers. Particulates containing these metals were sampled during sixteen sampling events at a copper smelter using the traditional NIOSH methods. Monitoring of particulates was simultaneously conducted using a TSI 8520 DustTrak real-time aerosol monitor with a 10-μm-cutpoint sampling inlet. NIOSH analytical methods related to particulates and metals (methods 0500, 0600 and 7300) were used to determine particulate mass and individual mass contributions of metals on sample filters. Linear regressions with y-intercepts forced to zero were developed to determine the relationship between the PM10measurements recorded by the DustTrak and laboratory-reported total particulate mass, PM10and respirable arsenic, cadmium, copper and lead concentrations. These linear regressions yielded correction factors that can be applied to DustTrak readings to obtain total particulate mass, PM10and respirable concentration estimates for each of the four metals. The R2(coefficient of determination) values from the linear regressions ranged from 0.65 for total lead to 0.91 for total copper. These results suggest that the DustTrak may produce real-time data useful in providing estimates for airborne concentrations of arsenic, cadmium, copper and lead in copper smelter particulates.

Insertional tendinopathies of the DDFT have been reported both as the sole lesion and as part of a multifocal lesion (Dyson et al.2003). Computed tomography (CT) and magnetic resonance imaging allow specific diagnosis of deep digital flexor tendon lesions within the hoof capsule; however, direct intralesional treatment of such lesions is difficult because of the hoof's rigid structure. A technique designed to mimic intralesional injection of insertional tendinopathies of the DDFT in the standing horse using radiographic guidance was assessed. Radiographic and contrast CT imaging and sectioning of the limbs confirmed accurate injection in all cases although inadvertant administration of injectate into adjacent structures was also evident.

The movement to price an increasing percentage of fed cattle on carcass merit grids has renewed interest in the effect of cattle disease on carcass traits. There is growing evidence that disease has the potential to affect not only carcass weight, but also the quantity, location, and ratio of muscle, fat, and water. A clear mechanistic pathway linking disease to changes in carcass traits has not been made. Three theories considered in this review are 1) a change in metabolic signals, such as cytokines and cortisol, could affect carcass composition through modification of hypothalamic secretions of thyrotropin-releasing hormone, by inhibition of IGF-I and insulin actions on muscle and fat tissues, and by direct protein catabolism and lipolysis; 2) disease-induced anorexia causing a decrease in serum IGF-I and an increase in serum GH, which induces a change in the partitioning of nutrients for tissue deposition; and 3) an indirect (and reversible) effect of anorexia, whereby sick cattle are on feed for fewer effective days than pen mates that do not become sick. Other pathogen or immune-mediated responses to disease, as well as interactions among hormones and cytokines, may influence nutrient partitioning and body composition but have yet to be described. The use of carcass merit to determine the value of fed cattle provides an improved economic signal of the cost of cattle disease. The value of disease avoidance as well as rapid diagnosis and treatment of disease increases when cattle are sold on carcass merit basis because of the negative effects of disease on carcass traits.

To identify primitive paths, which are centerlines of confining tubes, two leading methods, namely total quadratic energy minimization and length minimization, are explored and compared in molecular dynamics (MD) simulations of linear pearl-necklace polymer chains. Energy minimization leads to a slightly larger averaged length but much narrower contour length distribution around the average length than does length minimization. Applications of both methods to melts of linear polymers in MD simulations confirm a quadratic entropic potential governing the primitive path length distribution. However, length minimization leads to a prefactor of around 1.5, in agreement with the classical result of Doi and Edwards, while energy minimization gives a prefactor of around 3.0.

We study the effects of Marangoni stresses on the flow in an evaporating sessile droplet, by extending a lubrication analysis and a finite element solution of the flow field in a drying droplet, developed earlier.¹ The temperature distribution within the droplet is obtained from a solution of Laplace's equation, where quasi-steadiness and neglect of convection terms in the heat equation can be justified for small, slowly evaporating droplets. The evaporation flux and temperature profiles along the droplet surface are approximated by simple analytical forms and used as boundary conditions to obtain an axisymmetric analytical flow field from the lubrication theory for relatively flat droplets. A finite element algorithm is also developed to solve simultaneously the vapor concentration, and the thermal and flow fields in the droplet, which shows that the lubrication solution with the Marangoni stress is accurate for contact angles as high as 40°. From our analysis, we find that surfactant contamination, at a surface concentration as small as 300 molecules/μm², can almost entirely suppress the Marangoni flow in the evaporating droplet.

The axisymmetric time-dependent flow field in an evaporating sessile droplet whose contact line is pinned is studied numerically and using an analytical lubrication theory with a zero-shear-stress boundary condition on the free surface of the droplet at low capillary and Reynolds numbers. A finite element algorithm is developed to solve simultaneously the vapor concentration and flow field in the droplet under conditions of slow evaporation. The finite element solution confirms the accuracy of the lubrication solution, especially when terms of higher order in the droplet flatness ratio (the ratio of droplet height to radius, h/R) are included in the lubrication theory to account more accurately for the singular flow near the contact line.

Bead−spring Brownian dynamics simulations are herein used to model flow-induced chain scission in dilute polymer solutions in a planar cross-slot flow. The flow field is obtained by finite-element simulation for a Newtonian fluid at low Reynolds number (Re = 4.5), with the flow assumed to be unaffected by the polymer. Chain scission is defined to occur when any spring bears a force over a preset critical spring force. Multiple scission of the same chain in a single pass through the device is allowed. In the simulations, we observed both chain halving and quartering as reported in the experimental literature. However, in contrast to the common view that breakage occurs only in the stagnation point region, we find that the strong shearing flow generated near the walls of the inlet channel prestretches polymer molecules considerably, leading to breakage near the corner where an extensional flow is present. We also predict flow birefringence, which supports our finding that shear plays a significant role in chain scission in this geometry.

An integrated microfluidic device capable of performing a variety of genetic assays has been developed as a step towards building systems for widespread dissemination. The device integrates fluidic and thermal components such as heaters, temperature sensors, and addressable valves to control two nanoliter reactors in series followed by an electrophoretic separation. This combination of components is suitable for a variety of genetic analyses. As an example, we have successfully identified sequence-specific hemagglutinin A subtype for the ALA187 strain of influenza virus. The device uses a compact design and mass production technologies, making it an attractive platform for a variety of widely disseminated applications.

In melts of asymmetric three-arm star polymers in which a short arm is attached to two long, equal-length arms, the existing “tube” theory fails to predict how rapidly the motion of the branch-point becomes quenched when the length of the third, short, arm grows from zero length, for which the two other arms form a reptating linear chain, to a length equal to the other two arms, for which reptation is quenched. We use a simulation method that represents entanglements between two chains as “slip-links” that allow local relaxation of both chains when an end of either chain passes through the slip-link. We include an extreme form of branch-point motion in this algorithm and find that it can explain the anomalously rapid quenching of the branch-point if we assume that the time scale of the branch-point motion is set by the time required for the short arm to escape all entanglements, including those newly created while others are destroyed. The algorithm successfully predicts the linear viscoelasticity of H-polymers, where the acceleration induced by the polydispersity offsets the sluggishness introduced by adopting a drastically slow time scale for diffusion of the branch-point. Although the theory becomes unrealistic for long arms, it raises important questions about existing theories of branch-point motion and provides some clues to their resolution.

We introduce a fast and simple one-step method, a variation of the methods of Barrett and Campbell and Bartlett, to synthesize monodisperse fluorescent particles that can be dispersed in organic solvents and have long excitation (649 nm) and emission wavelengths (679 nm). A lipophilic fluorescent dye, 1,1‘-dioctadecyl-3,3,3‘,3‘-tetramethylindodicarbocyanine perchlorate, is directly incorporated into PMMA particles through dispersion polymerization. A poly(hydroxystearic acid) graft (poly) methyl methacrylate (MM) and methacrylic acid (MA) copolymer is used as a stabilizer to prevent the particles from aggregating and flocculating in the nonaqueous solvents. The fluorescent PMMA particles are very uniform in size, bleach at very low rate, and behave like hard spheres in their ordering on substrates. One important achievement in our synthesis protocol is that we are able to produce particles of a desired size by choosing the composition of the reactants according to a predetermined relationship between particle size and composition of reactants. In addition, the effects of fluorescent dye and polar solvent (ethanol) on the formation and size of particles are discussed.

The behavior of polymer molecules in dilute solutions under high-frequency oscillations is revisited, with consideration given to the barriers to bond rotation that we argue can make the chain dynamically rigid at high frequency. Thus, the dynamical Kuhn length of the chain exceeds the static one, and the chain at high frequencies acts like a freely jointed chain of “bent rigid wires” in which each bent rigid wire is a “dynamical Kuhn length” containing many static Kuhn lengths connected together in a rigid random walk. We show that this model is consistent with anomalous high-frequency behavior of polystyrene solutions under shear observed by Schrag and co-workers^1-3 and Amelar et al.⁴ and predicts that there is a minimum “spring” size corresponding roughly to exp[ΔEa/(3ν + 1)kBT] Kuhn steps that will behave elastically at high frequencies, where ΔEa is the barrier to bond rotation, and ν = 0.5−0.6 is the Flory exponent.

We extend the Milner−McLeish theory for monodisperse linear polymers to binary blends, where the reptation time of the long chain is set to either the reptation time in the undilated tube or the reptation time in the dilated tube depending on the value of the “Graessley parameter” Gr ≡ M2Me²/M1³, where M1 is the short chain molecular weight, M2 is the long chain molecular weight, and Me is the entanglement molecular weight. We find experimentally that, in blends in which Gr is much smaller than the critical value Grc ≈ 0.064 established by an observed crossover in diffusivity measurements [Green et al. Phys. Rev. Lett. 1984, 26, 2145], the long-chain motion in the binary blend is well predicted by the Milner−McLeish model using reptation in the undilated tube. However, for Gr larger than Grc, reptation must to be assumed to occur in a dilated tube to obtain agreement with the experimental data. These results confirm that the crossover behavior observed in diffusivity also occurs in rheology and show that existing tube models can accurately predict linear rheology in both regimes where reptation occurs in a dilated or an undilated tube.

Three-dimensional lattice-based Monte Carlo simulations of mixed amphiphile systems are investigated, and the simulated critical micelle concentrations (cmc's) are compared with the predictions of both a molecular thermodynamic theory and a regular solution theory. The head−head interactions between identical surfactant species are varied to mimic nonideal mixing and to manipulate the net attraction (or repulsion) between surfactant species. The simulations indicate that the head−head interaction affects not only the cmc but also aggregate size and structure. The simulated cmc as a function of overall surfactant composition is in reasonable agreement with the theoretical models when a fitted value for the interaction parameter, β, is used. The fitted value is in good agreement with a value estimated a priori from the lattice model for the surfactants with attractive headgroups, but there are large discrepancies for the case of repulsive headgroups. The discrepancies in the latter are caused by nonrandom mixing, that is, segregation of the two surfactants within each micelle.

AbstractNonprofit management courses appear in a wide range of graduate and certificate programs in the United States. The recent emergence of this academic field and the wide range of options for the institutional setting of nonprofit management programs have given rise to ongoing debates about these programs' content and focus. Recognizing that the student voice is often missing from these conversations about academic program development, we explored the perspectives of students enrolled in six U.S. nonprofit management programs on the relative importance of course topics typically included in nonprofit management curricula. Students rated as most important those course topics that are unique to the nonprofit sector and have an internal organization focus. Graduate students in nonprofit management programs and public administration programs with concentrations in nonprofit management express considerable agreement about the courses they see as important.

This paper describes the use of glass and mesoporous silica microspheres (typically 1−50 μm) as supports for biomimetic lipid bilayer membrane architectures for use in biotechnological applications. We present methods and characterization of lipid bilayer membranes supported on commercially available glass beads and mesoporous silica beads formed by an aerosol process that takes advantage of self-assembly of surfactant template phases in sol−gel synthesis. Methods for controlling the concentration of fluorescent lipids, ligands, receptors, and transmembrane proteins in the bead-supported bilayer assemblies are discussed, along with methods for measuring the concentration of these species using flow cytometry. Diffusion of molecular species both within the lipid bilayer and within the mesoporous bead structure is probed using fluorescence recovery after photobleaching. Flow cytometry and confocal fluorescence microscopy are used to examine dye uptake of the porous beads and the stability of the encapsulating lipid bilayer membranes to proton and fluorophore leakage. The studies presented herein form the basis for the use of several new types of biomimetic bead-supported bilayer architectures in a variety of biotechnological applications including microimmunoassays and fluorescence-based high-throughput screening of biochemical recognition and protein function.

The evaporation of a sessile droplet with a pinned contact line is investigated experimentally, by analytic theory and by computation using the finite element method (FEM). Because of the low value of R²/Dtf = cv(1 − H)/ρ = 1.4 × 10^-5, where R is the contact-line radius, D is the water vapor diffusivity, cv is the saturated water vapor concentration, H is the relative humidity, and ρ is the liquid water density, the evaporation can be considered as a quasi-steady-state process. Hence, the vapor concentration distribution above the droplet satisfies the Laplace equation but with a time-varying droplet surface. It is found both theoretically and experimentally that the net evaporation rate from the droplet remains almost constant with time for a small initial contact angle (θ &lt; 40°), even though the evaporation flux becomes more strongly singular at the edge of the droplet as the contact angle decreases during evaporation. We also measured the critical contact angle at which the contact line starts to recede and found that it is about 2−4° for clean water on glass. Finally, we compare the results obtained by our FEM analysis with an analytical solution and derive a very simple approximate evaporation rate expression &mdot;(t) = −πRD(1 − H)cv(0.27θ² + 1.30), which agrees with the theoretical results presented by Lebedev [Lebedev, N. N. Special Functions and Their Application; Prentice Hall:  Englewood Cliffs, New Jersey, 1965 and Picknett and Bexon [Picknett, R. G.; Bexon, R. J. Colloid Interface Sci. 1977, 61, 366] for any initial contact angle θ between 0 and π/2 with θ in radians. The approximate expression is also compared with droplet evaporation data from the literature, and good agreement is found without any parameter fitting.

The oxidation state of iron (Fe) in the crystal structure of smectite clay minerals profoundly alters their physical-chemical properties. Among the properties affected are layer charge, cation exchange and fixation capacity, swelling in water, particle size, specific surface area, layer stacking order, magnetic exchange interactions, octahedral site occupancy, surface acidity, and reduction potential. Also affected is the surface chemistry of the clay, which alters clay–water and clay–organic interaction mechanisms. Rates and extents of degradation of pesticides are increased in the presence of reduced smectites compared to oxidized and reduced-reoxidized counterparts. A hypothesis regarding the mechanism for Fe reduction in clay minerals was first developed in 1963, and subsequent modifications have been proposed periodically through the present time. Recent studies clearly reveal that the process of Fe reduction involves more than the mere transfer of an electron to octahedral Fe(III) in the clay crystal. Ancillary reactions occur that produce significant structural modifications, some of which are reversible and others of which are not. Such changes in the crystal-chemical environment of structural Fe are thought to play a dominant role in altering the clay surface chemistry.

Monoclonal antibodies against glutamic acid decarboxylase (anti-GAD) were modified with poly(ethylene glycol) (PEG), and the resulting conjugates were characterized. Monoclonal anti-GAD antibodies were purified from ATCC HB184 hybridoma cells by either cell culture supernatant or ascites fluid from BALB/c mice. Polyclonal rabbit IgG antibodies were also used as a model protein. Polyclonal rabbit IgG or purified anti-GAD was modified by PEG (MW = 5000 or 20000 Da) through either the lysine residues or through the carbohydrate moiety. Lysine modification was performed in PBS (pH 7.4) or 0.1 M borate (pH 9.2) by adding a molar excess (5−80) of a succinimidyl activated propionic acid terminated mPEG (SPA-PEG) while stirring at room temperature. Carbohydrate modifications were performed in PBS (pH 6.2) by first oxidizing the antibody with sodium periodate followed by incubation with hydrazide-terminated PEG followed by reduction with sodium cyanoborohydride. The degree of modification was assessed by ¹H NMR or TNBS (trinitrobenzenesulfonic acid). Circular dichroism (CD) spectra were obtained for lysine-modified rabbit IgG at various degrees of modification ranging from 5 to 60 PEG per antibody. Binding was assessed using an ELISA method with GAD or rabbit anti-mouse-IgG (H+L) coated plates. The TNBS and ¹H NMR analysis of the modified antibody showed reasonably similar results from 5 to 60 PEG per antibody. The ¹H NMR method showed greater sensitivity at low modifications (below 20:1) and was fairly linear up to about 60 PEG per antibody. The CD spectra of the polyclonal rabbit IgG showed only small differences at variously modified antibody. The binding affinity of anti-GAD is lower for all PEG modifications with respect to unmodified anti-GAD. Modifications at pH 7.4 show lower binding to GAD than modifications at pH 9.2. Binding to GAD or anti-mouse-IgG is decreased as the degree of modification is increased. Lysine modifications showed lower binding to GAD or anti-mouse-IgG than carbohydrate modifications. Binding to GAD or anti-mouse-IgG is lower for PEG20000-modified anti-GAD with respect to PEG5000-modified anti-GAD.

Hantavirus cardiopulmonary syndrome (HCPS) is a rare but frequently lethal acute zoonotic viral infection in rural North America. The rapidity of progression from febrile prodrome to cardiogenic shock and noncardiogenic pulmonary edema requiring intensive care creates high diagnostic urgency and a need for a rapid screening tool. In this retrospective cohort study, 2 pathologists scored blinded peripheral blood smears from 52 patients with HCPS and 128 seronegative patients referred for diagnosis of suspected hantavirus infection. During the prodromal phase, thrombocytopenia was the only consistent abnormality and could be used to indicate hantavirus serologic testing. After the onset of pulmonary edema detected radiographically, the presence of 4 of 5 findings (thrombocytopenia, myelocytosis, hemoconcentration, lack of significant toxic granulation in neutrophils, and more than 10% of lymphocytes with immunoblastic morphologic features) has a sensitivity for HCPS of 96% and a specificity of 99% and missed no patients with HCPS who required intensive care. While each abnormality is commonly seen, the combination of at least 4 of these CBC count data and peripheral blood smear findings can guide early treatment and patient transport decisions until rapid, specific, serologic testing becomes widely available.

Predictions of the Mead−Larson−Doi (MLD) and the Doi−Edwards−Marrucci−Grizzuti (DEMG) models¹ are compared with the rheological data in start up of steady shearing of concentrated bidisperse polystyrene solutions. Both the MLD and DEMG models are “tube” theories of flow with reptation, but the MLD theory includes both reptative and convective constraint-release effects, which are neglected in the DEMG theory. The adjustable parameters for the models are the reptation times (τd,i) of each molecular weight component, and the plateau modulus (%@mt;sys@%%@ital@%G%@rsf@%%@sx@%N%@be@%0%@sxx@%%@mx@% ). A procedure is given for obtaining the stretch times (τs,i) from the reptation times. The convective constraint release included in the MLD model remedies the extreme shear thinning predicted by the DEMG model, and the reptative constraint release extends the good predictions found for monodisperse polymers to bidisperse systems, especially at steady state. In the transient start up of shear for monodisperse polymers, both models provide good predictions in both the viscosities and the first normal stress differences at low shear rates. At high shear rates, the MLD model, as well as the DEMG model, can predict the strain at the peak in stress accurately; however, the magnitude of the overshoots predicted by the MLD model are not as high as those of the DEMG model, with the latter predicting overshoots that are closer to the observed results.

An algorithm is presented for predicting the linear viscoelasticity of polydisperse polymers containing long side branches with arbitrary distributions of branch length and branch location along a backbone. The algorithm gives semiquantitative predictions of literature data for a wide range of polybutadiene melts, including monodisperse linear, star, mixed linear and star, pom-pom, and comb polymers. Huge differences (several orders of magnitude) are predicted in zero-shear viscosities for samples that have the same weight-average molecular weight (200 000) and the same branching fraction but have different branching structures. It is shown that information on branching structure can be inferred by combinatorially measuring rheological properties on series of blends of the branched polymer with a linear, or well-defined branched, polymer.

Distinction of normal B-lymphoid proliferations including precursors known as hematogones from acute lymphoblastic leukemia (ALL) is critical for disease management. We present a multiparameter assessment of 27 bone marrow samples containing at least 25% hematogones (range, 25%-72%) by morphologic review. We used flow cytometry to evaluate B-cell differentiation antigen and adhesion molecule expression and immunohistochemistry on clot sections to evaluate architectural distribution. Flow cytometry revealed that intermediately differentiated cells (CD19+, CD10+) predominated, followed in frequency by CD20+, surface immunoglobulin-positive cells, with CD34+, terminal deoxynucleotidyl transferase (TdT)-positive cells as the smallest subset. Adhesion molecules (CD44, CD54) were expressed more heterogeneously compared with expression in acute lymphoblastic leukemia. Immunohistochemistry revealed that CD34+, TdT-positive cells were dispersed without significant clustering, while CD20+ cells exceeded CD34/TdT-positive cells in 24 of 25 cases. This multidisciplinary study demonstrates that hematogone-rich lymphoid proliferations exhibit a spectrum of B-lymphoid differentiation antigen expression with predominance of intermediate and mature B-lineage cells, heterogeneity of adhesion molecule expression, and nonclustered bone marrow architectural distribution.

Using Brownian dynamics simulations, we predict the deformation of a polymer coil in dilute solution and compare the results to direct measurements for DNA molecules and for polystyrene. For DNA, optical microscopy measurements of Smith and Chu yield measurements of 〈x〉, the average projected length of the molecule onto the flow direction as a function of shear rate, while for dilute polystyrene solutions, light scattering experiments yield 〈Rg²〉^1/2, the root-mean-square radius of gyration. Both measurements of deformation, 〈x〉 and 〈%@mt;sys@%%@ital@%R%@rsf@%%@sx@%g%@be@%2%@sxx@%%@mx@% 〉^1/2, are obtained from the simulations using input parameters required to match the molecular characteristics of both the DNA and the polystyrene solutions used in the experiments. We find that while the agreement between the simulations and the measurements of coil deformation for DNA is excellent, for polystyrene the measured deformation is much less than predicted.