Cylinders with Square Cross Section: Paths to Turbulence with Various Angles of Incidence

The path to turbulence in the wake of cylinders with square crosssection is investigated by means of direct numerical simulation, employing a two-dimensional spectral element method and Floquet linear stability analysis. The critical Reynolds number for the onset of the three-dimensional instability modes A, B, C and QP are reported for cylinder incidence angles between 0° and 45°. The Strouhal—Reynolds number relationship, and lift and drag coefficients are also investigated for these incidence angles. Reynolds numbers (based on the side length of the square) up to Re=300 are considered, and a significant variation in bifurcation scenarios are observed for the various incidence angles. At Reynolds numbers greater than Re ≈ 225 for an incidence angle of 45°, a previously unreported asymmetry is detected in the von Kármán vortex street. The cause of this asymmetry is investigated as it presents a possible alternative path to turbulence to that reported in the wakes of other bluff bodies

1.10 Quantifying Sources of Variability in Neonicotinoid Residue Data for Assessing Risks to Pollinators

The U.S. Environmental Protection Agency’s 2014 guidance for assessing pesticide risks to bees relies on higher-tier studies of residues in pollen and nectar to refine pesticide exposure estimates obtained from lower tier information (e.g., default values and model-generated estimates). These higher tier residue studies tend to be resource intensive due to the need to address spatial and temporal factors which influence pesticide residues in pollen and nectar. Time and resource considerations restrict the number of samples, crops, and locations which can be studied. Given these resource constraints, questions remain on how to best optimize the design and number of residue studies for obtaining a robust dataset to refine exposure estimates of bees to pesticides. Factors to be optimized include the number of replicates in each sampling event, the number of sampling events over time, the number of sites/regions per study, and the number of crops to be assessed within and across crop groups. Using available field residue data for the neonicotinoid class of insecticides, we conducted an analysis of variability in residue data to address these and other study design elements. Comparisons of the magnitude of residues and variability are made across neonicotinoid chemicals (imidacloprid, clothianidin, thiamethoxam and dinotefuran) as well as the variability associated with intra- and inter-crop group comparisons and regional and soil texture gradients. Additionally, this analysis includes consideration of bee-relevant toxic metabolites for imidacloprid and thiamethoxam. Results of these analyses of neonicotinoid residue data are presented in the context of optimizing field residue study designs for assessing pesticide risks to bees.The U.S. Environmental Protection Agency’s 2014 guidance for assessing pesticide risks to bees relies on higher-tier studies of residues in pollen and nectar to refine pesticide exposure estimates obtained from lower tier information (e.g., default values and model-generated estimates). These higher tier residue studies tend to be resource intensive due to the need to address spatial and temporal factors which influence pesticide residues in pollen and nectar. Time and resource considerations restrict the number of samples, crops, and locations which can be studied. Given these resource constraints, questions remain on how to best optimize the design and number of residue studies for obtaining a robust dataset to refine exposure estimates of bees to pesticides. Factors to be optimized include the number of replicates in each sampling event, the number of sampling events over time, the number of sites/regions per study, and the number of crops to be assessed within and across crop groups. Using available field residue data for the neonicotinoid class of insecticides, we conducted an analysis of variability in residue data to address these and other study design elements. Comparisons of the magnitude of residues and variability are made across neonicotinoid chemicals (imidacloprid, clothianidin, thiamethoxam and dinotefuran) as well as the variability associated with intra- and inter-crop group comparisons and regional and soil texture gradients. Additionally, this analysis includes consideration of bee-relevant toxic metabolites for imidacloprid and thiamethoxam. Results of these analyses of neonicotinoid residue data are presented in the context of optimizing field residue study designs for assessing pesticide risks to bees

A European Database of Fusarium graminearum and F-culmorum Trichothecene Genotypes

Fusarium species, particularly Fusarium graminearum and F culmorum, are the main cause of trichothecene type B contamination in cereals. Data on the distribution of Fusarium trichothecene genotypes in cereals in Europe are scattered in time and space. Furthermore, a common core set of related variables (sampling method, host cultivar, previous crop, etc.) that would allow more effective analysis of factors influencing the spatial and temporal population distribution, is lacking. Consequently, based on the available data, it is difficult to identify factors influencing chemotype distribution and spread at the European level. Here we describe the results of a collaborative integrated work which aims (1) to characterize the trichothecene genotypes of strains from three Fusarium species, collected over the period 2000-2013 and (2) to enhance the standardization of epidemiological data collection. Information on host plant, country of origin, sampling location, year of sampling and previous crop of 1147 F graminearurn, 479 F culmorum, and 3 F cortaderiae strains obtained from 17 European countries was compiled and a map of trichothecene type B genotype distribution was plotted for each species. All information on the strains was collected in a freely accessible and updatable database (www.catalogueeu.luxmcc.lu), which will serve as a starting point for epidemiological analysis of potential spatial and temporal trichothecene genotype shifts in Europe. The analysis of the currently available European dataset showed that in F. grarninearum, the predominant genotype was 15-acetyldeoxynivalenol (15-ADON) (82.9%), followed by 3-acetyldeoxynivalenol (3-ADON) (13.6%), and nivalenol (NIV) (3.5%). In F culmorum, the prevalent genotype was 3-ADON (59.9%), while the NIV genotype accounted for the remaining 40.1%. Both, geographical and temporal patterns of trichothecene genotypes distribution were identified.Ministere de l'Agriculture, de la Viticulture et de la Protection des Consommateurs-Administration des Services Techniques de l'Agriculture; M.I.U.R. Project AGROGEN (Laboratory of GENomics for traits of AGROnomic importance in durum wheat: Identification of useful genes, functional analysis and assisted selection by biological markers for the development of the national seed chain) [602/Ric]; Felix Thornley Cobbold Trust; John Oldacre Foundation; Ministry of Agriculture of the Czech RepublicMinistry of Agriculture, Czech Republic [800415]; Spanish Ministry MINECOSpanish Government [AGL201.4-53928-C2-2-R]; Ministry of Agriculture and Food, Norway; Federal Ministry of Education and Research (BMBF) (GABI-KANADA), BonnFederal Ministry of Education & Research (BMBF) [FKZ 0313711A]; German Academic Exchange Service (DAAD), BonnDeutscher Akademischer Austausch Dienst (DAAD) [A/06/92183]; Finnish Ministry of Agriculture and Forestry; Direction Generale de l'Agriculture, Direction de la Recherche [D31-3159, D31-1162, D31-7055]; P.O.R. SARDEGNA F.S.; Danish Directorate for Food, Fisheries and Agri Business [FFS05-3]; Academy of FinlandAcademy of Finland [126917, 131957, 250904, 252162, 267188, 266984]; Olvi Foundation; Turku University Foundation; CIMO travel grant; Nordic network project New Emerging Mycotoxins and Secondary Metabolites in Toxigenic Fungi of Northern Europe - Nordic Research Board [090014]The Luxembourg institute of Science and Technology, LU, acknowledges the Ministere de l'Agriculture, de la Viticulture et de la Protection des Consommateurs-Administration des Services Techniques de l'Agriculture for financially supporting the Sentinelle project. The work on Italian strains has been financially supported through the M.I.U.R. Project AGROGEN (Laboratory of GENomics for traits of AGROnomic importance in durum wheat: Identification of useful genes, functional analysis and assisted selection by biological markers for the development of the national seed chain) (D. D. 14.03.2005 n. 602/Ric). Funding for the research of Ryan Basler was provided by Felix Thornley Cobbold Trust and the John Oldacre Foundation.; The work of JC was supported by the Ministry of Agriculture of the Czech Republic, Project No. 800415. The research of MG and PG was supported by the Spanish Ministry MINECO (AGL201.4-53928-C2-2-R). The Ministry of Agriculture and Food, Norway funded the work of IH. The research of TM was funded by the Federal Ministry of Education and Research (BMBF) (GABI-KANADA #FKZ 0313711A), Bonn and by the German Academic Exchange Service (DAAD), Bonn (code no.: A/06/92183). PP acknowledges the Finnish Ministry of Agriculture and Forestry for funding the project FinMyco on Fusarium and mycotoxins in Finland. The research of JS was funded by the Direction Generale de l'Agriculture, Direction de la Recherche (ref. D31-3159, D31-1162, D31-7055), in the framework of a project entitled Caracterization et dynamique des fusarioses sur mais en Region Wallonne. BS acknowledges support by P.O.R. SARDEGNA F.S.E. 2007-2013-Obiettivo competitivita regionale e occupazione, Asse IV Capitale umano, Linea di Attivita 1.3.1 (research project Identification of natural and natural-like molecules inhibiting mycotoxin biosynthesis by Fusaria pathogenic on cereals). UT thanks the Danish Directorate for Food, Fisheries and Agri Business grant FFS05-3 for financial support. The work of TY was financially supported by the Academy of Finland (no. 126917, 131957, 250904, 252162, 267188, and 266984), Olvi Foundation, Turku University Foundation, a CIMO travel grant to Taha Hussien, and the Nordic network project New Emerging Mycotoxins and Secondary Metabolites in Toxigenic Fungi of Northern Europe (project 090014), which was funded by the Nordic Research Board

Despite NAIS concerns electronic identification use by cow-calf producers is increasing

The proposed U.S. National Animal Identification System has generated concerns among producers relative to implementation of the system. Many of these concerns stem from the USDA’s Bovine Identification Working Group’s recommendations to use electronic Identification Plan Bovine Working Group has recommended radio frequency identification as the technology to individually identify cattle. Understanding and implementing an electronic identification system for cow-calf producers is believed to be one of the greatest challenges of implementing the National Animal Identification System

Dehydration entropy drives liquid-liquid phase separation by molecular crowding

Liquid-liquid phase separation occurs in cells and can be induced in artificial systems, but the mechanism of the effect of molecular crowders is unclear. Here dehydration entropy-driven phase separation of model charged polymers lacking any chemical complexity or hydrophobicity is shown to be enhanced by polyethylene glycol. Complex coacervation driven liquid-liquid phase separation (LLPS) of biopolymers has been attracting attention as a novel phase in living cells. Studies of LLPS in this context are typically of proteins harboring chemical and structural complexity, leaving unclear which properties are fundamental to complex coacervation versus protein-specific. This study focuses on the role of polyethylene glycol (PEG)-a widely used molecular crowder-in LLPS. Significantly, entropy-driven LLPS is recapitulated with charged polymers lacking hydrophobicity and sequence complexity, and its propensity dramatically enhanced by PEG. Experimental and field-theoretic simulation results are consistent with PEG driving LLPS by dehydration of polymers, and show that PEG exerts its effect without partitioning into the dense coacervate phase. It is then up to biology to impose additional variations of functional significance to the LLPS of biological systems.11Ysciescopu