Heterogeneous condensation of the Lennard-Jones vapor onto a nanoscale seed particle

The heterogeneous condensation of a Lennard-Jones vapor onto a nanoscale seed particle is studied using molecular dynamics simulations. Measuring the nucleation rate and the height of the free energy barrier using the mean first passage time method shows that the presence of a weakly interacting seed has little effect on the work of forming very small cluster embryos but accelerates the rate by lowering the barrier for larger clusters. We suggest that this results from a competition between the energetic and entropic features of cluster formation in the bulk and at the heterogeneity. As the interaction is increased, the free energy of formation is reduced for all cluster sizes. We also develop a simple phenomenological model of film formation on a small seed that captures the general features of the nucleation process for small heterogeneities. A comparison of our simulation results with the model shows that heterogeneous classical nucleation theory provides a good estimate of the critical size of the film but significantly over-estimates the size of the barrier.Comment: 9 pages, 10 figures, In Print J. Chem. Phy

Efficacy of a sensory deterrent and pipe modifications in decreasing entrainment of juvenile green sturgeon (Acipenser medirostris) at unscreened water diversions.

Water projects designed to extract fresh water for local urban, industrial and agricultural use throughout rivers and estuaries worldwide have contributed to the fragmentation and degradation of suitable habitat for native fishes. The number of water diversions located throughout the Sacramento-San Joaquin watershed in California's Central Valley exceeds 3300, and the majority of these are unscreened. Many anadromous fish species are susceptible to entrainment into these diversions, potentially impacting population numbers. In the laboratory, juvenile green sturgeon (Acipenser medirostris) have been shown to have high entrainment rates into unscreened diversions compared with those of other native California fish species, which may act as a significant source of mortality for this already-threatened species. Therefore, we tested the efficacy of a sensory deterrent (strobe light) and two structural pipe modifications (terminal pipe plate and upturned pipe configuration) in decreasing the entrainment of juvenile green sturgeon (mean mass ± SEM = 162.9 ± 4.0 g; mean fork length = 39.4 ± 0.3 cm) in a large (>500 kl) outdoor flume fitted with a water-diversion pipe 0.46 m in diameter. While the presence of the strobe light did not affect fish entrainment rates, the terminal pipe plate and upturned pipe modifications significantly decreased the proportion of fish entrained out of the total number tested relative to control conditions (0.13 ± 0.02 and 0.03 ± 0.02 vs. 0.44 ± 0.04, respectively). These data suggest that sensory deterrents using visual stimuli are not an effective means to reduce diversion pipe interactions for green sturgeon, but that structural alterations to diversions can successfully reduce entrainment for this species. Our results are informative for the development of effective management strategies to mitigate the impacts of water diversions on sturgeon populations and suggest that effective restoration strategies that balance agricultural needs with conservation programmes are possible

Unscreened water-diversion pipes pose an entrainment risk to the threatened green sturgeon, Acipenser medirostris.

Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California) watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained) and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (35±0.6 cm mean fork length) to entrainment in a large (>500-kl) outdoor flume with a 0.46-m-diameter water-diversion pipe. Fish entrainment was generally high (range: 26-61%), likely due to a lack of avoidance behavior prior to entering inescapable inflow conditions. We estimated that up to 52% of green sturgeon could be entrained after passing within 1.5 m of an active water-diversion pipe three times. These data suggest that green sturgeon are vulnerable to unscreened water-diversion pipes, and that additional research is needed to determine the potential impacts of entrainment mortality on declining sturgeon populations. Data under various hydraulic conditions also suggest that entrainment-related mortality could be decreased by extracting water at lower diversion rates over longer periods of time, balancing agricultural needs with green sturgeon conservation

Pain Coping Skills Training for Patients Who Catastrophize About Pain Prior to Knee Arthroplasty: A Multisite Randomized Clinical Trial

BACKGROUND: Pain catastrophizing has been identified as a prognostic indicator of poor outcome following knee arthroplasty. Interventions to address pain catastrophizing, to our knowledge, have not been tested in patients undergoing knee arthroplasty. The purpose of this study was to determine whether pain coping skills training in persons with moderate to high pain catastrophizing undergoing knee arthroplasty improves outcomes 12 months postoperatively compared with usual care or arthritis education. METHODS: A multicenter, 3-arm, single-blinded, randomized comparative effectiveness trial was performed involving 5 university-based medical centers in the United States. There were 402 randomized participants. The primary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain Scale, measured at baseline, 2 months, 6 months, and 12 months following the surgical procedure. RESULTS: Participants were recruited from January 2013 to June 2016. In 402 participants, 66% were women and the mean age of the participants (and standard deviation) was 63.2 ± 8.0 years. Three hundred and forty-six participants (90% of those who underwent a surgical procedure) completed a 12-month follow-up. All 3 treatment groups had large improvements in 12-month WOMAC pain scores with no significant differences (p > 0.05) among the 3 treatment arms. No differences were found between WOMAC pain scores at 12 months for the pain coping skills and arthritis education groups (adjusted mean difference, 0.3 [95% confidence interval (CI), -0.9 to 1.5]) or between the pain coping and usual-care groups (adjusted mean difference, 0.4 [95% CI, -0.7 to 1.5]). Secondary outcomes also showed no significant differences (p > 0.05) among the 3 groups. CONCLUSIONS: Among adults with pain catastrophizing undergoing knee arthroplasty, cognitive behaviorally based pain coping skills training did not confer pain or functional benefit beyond the large improvements achieved with usual surgical and postoperative care. Future research should develop interventions for the approximately 20% of patients undergoing knee arthroplasty who experience persistent function-limiting pain. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence

An Exploratory Study of Value Added Services

Purpose: Using data from 104 countries over a six-year period (2009-2014), this study proposes a value-added predictor in service industries based on the eight indicators of the prosperity index, namely economy, entrepreneurship and opportunity, governance, education, health, safety and security, personal freedom, and social capital. Design/methodology/approach: The fuzzy-set qualitative comparative analysis (fsQCA) and complexity theory, a relatively novel approach for developing and testing the conceptual model, are used for asymmetric modelling of value added in service industries, and the predictive validity of the proposed configural model is tested. Findings: Apart from advancing method and theory, this study simulates causal conditions (i.e., recipes) leading to both high and low scores of the value added of services. The configural conditions indicating a high/low level of value added in service industries can be used as a guiding strategy for marketers, investors and policy makers. Originality/value: An analysis of worldwide data provides complex models demonstrating both how to regulate country conditions to achieve a high value-added score and select a foreign country for investment that offers a high level of value added service

Quantitative trait loci conferring grain mineral nutrient concentrations in durum wheat 3 wild emmer wheat RIL population

Mineral nutrient malnutrition, and particularly deficiency in zinc and iron, afflicts over 3 billion people worldwide. Wild emmer wheat, Triticum turgidum ssp. dicoccoides, genepool harbors a rich allelic repertoire for mineral nutrients in the grain. The genetic and physiological basis of grain protein, micronutrients (zinc, iron, copper and manganese) and macronutrients (calcium, magnesium, potassium, phosphorus and sulfur) concentration was studied in tetraploid wheat population of 152 recombinant inbred lines (RILs), derived from a cross between durum wheat (cv. Langdon) and wild emmer (accession G18-16). Wide genetic variation was found among the RILs for all grain minerals, with considerable transgressive effect. A total of 82 QTLs were mapped for 10 minerals with LOD score range of 3.2–16.7. Most QTLs were in favor of the wild allele (50 QTLs). Fourteen pairs of QTLs for the same trait were mapped to seemingly homoeologous positions, reflecting synteny between the A and B genomes. Significant positive correlation was found between grain protein concentration (GPC), Zn, Fe and Cu, which was supported by significant overlap between the respective QTLs, suggesting common physiological and/or genetic factors controlling the concentrations of these mineral nutrients. Few genomic regions (chromosomes 2A, 5A, 6B and 7A) were found to harbor clusters of QTLs for GPC and other nutrients. These identified QTLs may facilitate the use of wild alleles for improving grain nutritional quality of elite wheat cultivars, especially in terms of protein, Zn and Fe

Effects of Supersymmetric Threshold Corrections on High-Scale Flavor Textures

Integration of superpartners out of the spectrum induces potentially large contributions to Yukawa couplings. These corrections, the supersymmetric threshold corrections, therefore influence the CKM matrix prediction in a non-trivial way. We study effects of threshold corrections on high-scale flavor structures specified at the gauge coupling unification scale in supersymmetry. In our analysis, we first consider high-scale Yukawa textures which qualify phenomenologically viable at tree level, and find that they get completely disqualified after incorporating the threshold corrections. Next, we consider Yukawa couplings, such as those with five texture zeroes, which are incapable of explaining flavor-changing proceses. Incorporation of threshold corrections, however, makes them phenomenologically viable textures. Therefore, supersymmetric threshold corrections are found to leave observable impact on Yukawa couplings of quarks, and any confrontation of high-scale textures with experiments at the weak scale must take into account such corrections.Comment: 25 pages, submitted to JHE

Measuring regional creative capacity: A literature review for rural-specific approaches

Recent theories on regional creative capacity often focus on urban regions without taking into account rural regions. In addition, the application of such analyses to rural regions may lead to misrepresentation or misunderstanding of rural creative capacity. Against this background, the aim of the present study is to integrate the existing literature on different components of creative capacity, namely, knowledge, innovation, entrepreneurship and networks, in order to build a more comprehensive framework for rural creative capacity and its evaluation. In the light of the perspective from the empirical literature review on the evaluation of creative capacity in rural regions, various empirical measurements seem to misrepresent or underestimate the creative capacity of rural regions. Therefore, there is a clear need to use the locality in relation to its dynamics, i.e. tacit knowledge, cultural heritage and social and physical environment as the main and basic measurement unit for creative capacity analysis. 2010 Taylor & Francis