940 research outputs found
Nuclear structure study around Z=28
Yrast levels of Ni, Cu and Zn isotopes for have been
described by state-of-the-art shell model calculations with three recently
available interactions using Ni as a core in the model
space. The results are unsatisfactory viz. large for very neutron rich
nuclei, small B(E2) values in comparison to experimental values. These results
indicate an importance of inclusion of and orbitals
in the model space to reproduce collectivity in this region.Comment: 12 pages, 14 figure
DNA Barcoding Identifies Unknown Females and Larvae of Fannia R.-D. (Diptera: Fanniidae) from Carrion Succession Experiment and Case Report.
Application of available keys to European Fanniidae did not facilitate unequivocal species identification for third instar larvae and females of Fannia Robineau-Desvoidy, 1830 collected during a study of arthropod succession on pig carrion. To link these samples to known species, we took the advantage of molecular identification methods and compared newly obtained cytochrome oxidase subunit I (COI) barcode sequences against sequences deposited in reference databases. As an outcome of the results obtained, we describe for the first time a third instar larva of Fannia nigra Malloch, 1910 and Fannia pallitibia (Rondani, 1866) and a female of Fannia collini d'Assis-Fonseca, 1966. We provide combinations of characters allowing for discrimination of described insects from other Fanniidae. We provide an update for the key by Rozkošný et al. 1997, which allows differentiation between females of F. collini and other species of Fanniidae. Additionally, we provide a case of a human cadaver discovered in Southern Poland and insect fauna associated with it as the first report of F. nigra larvae developing on a human body
First observation of 55,56Zn
In an experiment at the SISSI/LISE3 facility of GANIL, the most proton-rich
zinc isotopes 55,56Zn have been observed for the first time. The experiment was
performed using a high-intensity 58Ni beam at 74.5 MeV/nucleon impinging on a
nickel target. The identification of 55,56Zn opens the way to 54Zn, a good
candidate for two-proton radioactivity according to theoretical predictions.Comment: 2 pages, 1 figure, accepted for publication in Eur. Phys. J.
Decay of proton-rich nuclei between 39Ti and 49Ni
Decay studies of very neutron-deficient nuclei ranging from 39Ti to 49Ni have
been performed during a projectile fragmentation experiment at the GANIL/LISE3
separator. For all nuclei studied in this work, 39,40Ti, 42,43Cr, 46Mn,
45,46,47Fe and 49Ni, half-lives and decay spectra have been measured. In a few
cases, gamma coincidence measurements helped to successfully identify the
initial and final states of transitions. In these cases, partial decay scheme
are proposed. For the most exotic isotopes, 39Ti, 42Cr, 45Fe and 49Ni, which
are candidates for two-proton radioactivity from the ground state, no clear
evidence of this process is seen in our spectra and we conclude rather on a
delayed particle decay.Comment: 12 pages, 15 figures, submitted for publication in Eur. Phys. J.
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The efficacy and sustainability of the CIMBAA transgenic Cry1B/Cry1C Bt cabbage and cauliflower plants for control of lepidopteran pests
In 2003 the Collaboration on Insect Management for Brassicas in Asia and Africa (CIMBAA) public/private partnership selected the Cry1B/Cry1C Bt protein combination as having the potential to provide effective and sustainable control of diamondback moth (DBM), Plutella xylostella. Following transformations and extensive plant selection, insect efficacy trials were undertaken in 2008 to 2010 in north India (Murthal near New Delhi) and south India (near Bengaluru) in large scale screen-house experiments using artificial infestations on the best performing (Elite Event) plant lines and on hybrids produced from them. Plant damage was scored on a scale of 0 (no visible damage) to 4 (plant effectively destroyed). For DBM, cabbage cluster caterpillar (Crocidolomia binotalis), cabbage webworm (Hellula undalis) and semi-looper (Trichoplusia ni) there was zero insect survival and a zero damage score on the Elite Event lines and on their hybrids, while control plants had 50 to 100% insect survival (depending on species, life stage and trials) and damage scores of 3.3 to 4. Cabbage white (Pieris brassicae) and common army worm (Spodoptera litura) showed some larval survival and damage scores up to 1.4 (especially in early trials) but no survival to pupation. Screening of DBM populations worldwide (inc. 18 populations for Cry1B and 13 for Cry1C from India) showed mean LC50s close to that of international susceptible strains. To date F2 screening has not identified the presence of resistance genes in DBM in the field. Cry1B resistance was slowly developed artificially in the laboratory but 1C resistance and resistance to the Cry1B/1C combination was harder to develop and had higher fitness costs. The ‘resistant’ lines showed some extended survival of stunted DBM larvae on dual gene Bt plants but no survival to pupation. There was no cross-resistance between Cry1B and Cry1C. Resistance to both genes was autosomal and recessive. Beneficial insects were demonstrated to have the potential to provide additional mortality on rare surviving insects in Bt fields. Aphids were well controlled for the first 40 days post-transplanting using imidacloprid pelleted onto seed and, if necessary, by 1-2 Verticillium lecanii sprays thereafter. Surviving S. litura and Helicoverpa armigera in Bt sprayed fields were well controlled by one or two application
Confocal laser scanning microscopy as a valuable tool in Diptera larval morphology studies
Larval morphology of flies is traditionally studied using light microscopy, yet in the case of fine structures compound light microscopy is limited due to problems of resolution, illumination and depth of field, not allowing for precise recognition of sclerites’ edges and interactions. Using larval instars of cyclorrhaphan Diptera, we show the usefulness of confocal laser scanning microscopy (CLSM) for studying the morphological characters of immature stages by taking advantage of the autofluorescent properties of cephaloskeleton structures. We compare data obtained from killed but unprepared larvae with those from larvae prepared by clearing according to two commonly used methods, either with potassium hydroxide or with Hoyer’s medium. We also evaluated the CLSM application for examining already slide-mounted larvae stored in museum collections and those freshly prepared. Our results indicate that CLSM and 3D reconstruction are excellent for visualizing small, compound structures of cylrorrhaphan larvae cephaloskeleton, if appropriate clearing techniques, i.e. the application of KOH, are used. Maximum intensity projection of confocal data sets obtained from material freshly prepared and that stored in museum collection does not differ. Because of this and the fact that KOH is commonly used as a clearing method to examine the cephaloskeleton of Diptera larvae, it is possible, and highly recommended, to use slides already prepared with this method for re-examination by CLSM. We conclude that CLSM application can be an invaluable source of data for studies of larval morphology of Cyclorrhapha by way of taxonomic diagnoses, character identification and improvement in characters homologization.This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited
Realistic Shell-Model Calculations for Proton-Rich N=50 Isotones
The structure of the N=50 isotones 98Cd, 97Ag, and 96Pd is studied in terms
of shell model employing a realistic effective interaction derived from the
Bonn-A nucleon-nucleon potential. The single-hole energies are fixed by
resorting to an analysis of the low-energy spectra of the isotones with A>= 91.
Comparison shows that our results are in very satisfactory agreement with the
available experimental data. This supports confidence in the predictions of our
calculationsComment: 8 pages, 3 figures, to be published on Journal of Physics
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