Do background levels of the pesticide pirimiphosmethyl in plant-based aquafeeds affect food safety of farmed Atlantic salmon?

The substitution of fish oil and fishmeal with plant-based ingredients in commercial aquafeeds for Atlantic salmon, may introduce novel contaminants that have not previously been associated with farmed fish. The organophosphate pesticide pirimiphos-methyl (PM) is one of the novel contaminants that is most prevalent in commercial salmon feed. In this study, the feed-to-fillet transfer of dietary PM and its main metabolites was investigated in Atlantic salmon fillet. Based on the experimental determined PM and metabolite uptake, metabolisation, and elimination kinetics, a physiologically based toxicokinetic (PBTK) compartmental model was developed. Fish fed PM had a relatively low (~4%) PM retention and two main metabolites (2-DAMP and Desethyl-PM) were identified in liver, muscle, kidney and bile. The absence of more metabolised forms of 2-DAMP and Desethyl-PM in Atlantic salmon indicates different metabolism in cold-water fish compared to previous studies on ruminants. The model was used to simulate the long term (>1.5 years) feed-to-fillet transfer of PM + metabolite in Atlantic salmon under realistic farming conditions including seasonal fluctuations in feed intake, growth, and fat deposition in muscle tissue. The model predictions show that with the constant presence of the highest observed PM concentration in commercial salmon feed, fillet PM+ metabolite levels were approximately 5 nmol kg−1, with highest levels for the metabolite 2-DAMP. No EU maximum residue levels (MRL) for PM and its main metabolites exist in seafood to date, but the predicted levels were lower than the MRL for PM in swine of 32.7 nmol kg−1.publishedVersio

An explicit approach to conceptual density functional theory descriptors of arbitrary order

We present explicit formulas for arbitrary-order derivatives of the energy, grand potential, electron density, and higher-order response functions with respect to the number of electrons, and the chemical potential for any smooth and differentiable model of the energy versus the number of electrons. The resulting expressions for global reactivity descriptors (hyperhardnesses and hypersoftnesses), local reactivity descriptors (hyperFukui functions and local hypersoftnesses), and nonlocal response functions are easy to evaluate computationally. Specifically, the explicit formulas for global/local/nonlocal hypersoftnesses of arbitrary order are derived using Bell polynomials. Explicit expressions for global and local hypersoftness indicators up to fifth order are presented. (C) 2016 Elsevier B.V. All rights reservedVanier-CGS fellowship Ghent University CONACYT FONDECYT 114031

Multi-Scale Sampling to Evaluate Assemblage Dynamics in an Oceanic Marine Reserve

To resolve the capacity of Marine Protected Areas (MPA) to enhance fish productivity it is first necessary to understand how environmental conditions affect the distribution and abundance of fishes independent of potential reserve effects. Baseline fish production was examined from 2002–2004 through ichthyoplankton sampling in a large (10,878 km2) Southern Californian oceanic marine reserve, the Cowcod Conservation Area (CCA) that was established in 2001, and the Southern California Bight as a whole (238,000 km2 CalCOFI sampling domain). The CCA assemblage changed through time as the importance of oceanic-pelagic species decreased between 2002 (La Niña) and 2003 (El Niño) and then increased in 2004 (El Niño), while oceanic species and rockfishes displayed the opposite pattern. By contrast, the CalCOFI assemblage was relatively stable through time. Depth, temperature, and zooplankton explained more of the variability in assemblage structure at the CalCOFI scale than they did at the CCA scale. CalCOFI sampling revealed that oceanic species impinged upon the CCA between 2002 and 2003 in association with warmer offshore waters, thus explaining the increased influence of these species in the CCA during the El Nino years. Multi-scale, spatially explicit sampling and analysis was necessary to interpret assemblage dynamics in the CCA and likely will be needed to evaluate other focal oceanic marine reserves throughout the world

Photodisintegration of 4^4He into p+t

The two-body photodisintegration of $^4$He into a proton and a triton has been studied using the CEBAF Large-Acceptance Spectrometer (CLAS) at Jefferson Laboratory. Real photons produced with the Hall-B bremsstrahlung-tagging system in the energy range from 0.35 to 1.55 GeV were incident on a liquid $^4$He target. This is the first measurement of the photodisintegration of $^4$He above 0.4 GeV. The differential cross sections for the $\gamma$$^4$He$\to pt$ reaction have been measured as a function of photon-beam energy and proton-scattering angle, and are compared with the latest model calculations by J.-M. Laget. At 0.6-1.2 GeV, our data are in good agreement only with the calculations that include three-body mechanisms, thus confirming their importance. These results reinforce the conclusion of our previous study of the three-body breakup of $^3$He that demonstrated the great importance of three-body mechanisms in the energy region 0.5-0.8 GeV .Comment: 13 pages submitted in one tgz file containing 2 tex file and 22 postscrip figure

Exclusive Photoproduction of the Cascade (Xi) Hyperons

We report on the first measurement of exclusive Xi-(1321) hyperon photoproduction in gamma p --> K+ K+ Xi- for 3.2 < E(gamma) < 3.9 GeV. The final state is identified by the missing mass in p(gamma,K+ K+)X measured with the CLAS detector at Jefferson Laboratory. We have detected a significant number of the ground-state Xi-(1321)1/2+, and have estimated the total cross section for its production. We have also observed the first excited state Xi-(1530)3/2+. Photoproduction provides a copious source of Xi's. We discuss the possibilities of a search for the recently proposed Xi5-- and Xi5+ pentaquarks.Comment: submitted to Phys. Rev.

The Use of a Disclosing Agent During Resective Periodontal Surgery for Improved Removal of Biofilm

A total removal of the bacterial deposits is one of the main challenges of periodontal therapy. A surgical approach is sometimes required in order to allow a correct access to the areas not thoroughly reached during the initial therapy. The present study focuses on the surgical scaling effectiveness in root deposits removal; the potential support of a disclosing agent during this procedure is also evaluated. Forty surgical periodontal patients were randomly divided between surgeries where the operator was informed about a final examination of the residual root deposits and surgeries where the operator was not informed. Straight after scaling procedures a supervisor recorded the O’Leary Plaque Index of the exposed roots by mean of a disclosing agent and the percentage of teeth with residual biofilm. After the stained deposits removal, a second chromatic examination was performed and new data were collected. Mann-Whitney U-test and Wilcoxon test for paired samples were used for comparisons respectively between the two surgery groups and the first and the second chromatic examination; one-sided p-value was set at 0.05. At first examination no significant differences between the two groups were observed regarding Plaque Index (p=0.24) and percentages of teeth with residual biofilm (p=0.07). The 100% removal of roots deposits was never achieved during the study but a significant reduction of 80% of root deposits was observed between first and second examination (p=0.0001). Since root deposits removal during periodontal surgery resulted always suboptimal, the use of a disclosing agent during this procedure could be a useful and practical aid

Genome\u2011wide diversity and runs of homozygosity in the \u201cBraque Fran\ue7ais, type Pyr\ue9n\ue9es\u201d dog breed

Objective: Braque Fran\uc3\ua7ais, type Pyr\uc3\ua9n\uc3\ua9es is a French hunting-dog breed whose origin is traced back to old pointing gun-dogs used to assist hunters in finding and retrieving game. This breed is popular in France, but seldom seen elsewhere. Despite the ancient background, the literature on its genetic characterization is surprisingly scarce. A recent study looked into the demography and inbreeding using pedigree records, but there is yet no report on the use of molecular markers in this breed. The aim of this work was to genotype a population of Braque Fran\uc3\ua7ais, type Pyr\uc3\ua9n\uc3\ua9es dogs with the high-density SNP array to study the genomic diversity of the breed. Results: The average observed (HO) and expected (HE) heterozygosity were 0.371 (\uc2\ub1 0.142) and 0.359 (\uc2\ub1 0.124). Effective population size (NE) was 27.5635 runs of homozygosity (ROH) were identified with average length of 2.16 MB. A ROH shared by 75% of the dogs was detected at the beginning of chromosome 22. Inbreeding coefficients from marker genotypes were in the range FIS= [- 0.127, 0.172]. Inbreeding estimated from ROH (FROH) had mean 0.112 (\uc2\ub1 0.023), with range [0.0526, 0.225]. These results show that the Braque Fran\uc3\ua7ais, type Pyr\uc3\ua9n\uc3\ua9es breed is a relatively inbred population, but with still sufficient genetic variability for conservation and genetic improvement