TB123: Experimental Application of B.t.i. for Larval Black Fly Control: Persistance and Downstream Carry, Efficacy, Impact on Non-target Invertebrates and Fish Feeding

In the summer of 1985 a field experiment was conducted in the Sugarloaf area of Maine on the use of B.t.i. to reduce the numbers of black fly larvae in the Carrabassett River and a tributary stream. The objectives were to determine the rate of application necessary to produce an acceptable reduction in black fly larvae, to study the fate and persistence of B.t.i. in a stream following application, to determine the impact of B.t.i. on the abundance and drift of non-target stream insects and on the feeding success and diet composition of fishes in the treated streams.https://digitalcommons.library.umaine.edu/aes_techbulletin/1083/thumbnail.jp

Identification of a bacteriocin and its cognate immunity factor expressed by Moraxella catarrhalis

<p>Abstract</p> <p>Background</p> <p>Bacteriocins are antimicrobial proteins and peptides ribosomally synthesized by some bacteria which can effect both intraspecies and interspecies killing.</p> <p>Results</p> <p><it>Moraxella catarrhalis </it>strain E22 containing plasmid pLQ510 was shown to inhibit the growth of <it>M. catarrhalis </it>strain O35E. Two genes (<it>mcbA </it>and <it>mcbB</it>) in pLQ510 encoded proteins predicted to be involved in the secretion of a bacteriocin. Immediately downstream from these two genes, a very short ORF (<it>mcbC</it>) encoded a protein which had some homology to double-glycine bacteriocins produced by other bacteria. A second very short ORF (<it>mcbI</it>) immediately downstream from <it>mcbC </it>encoded a protein which had no significant similarity to other proteins in the databases. Cloning and expression of the <it>mcbI </it>gene in <it>M. catarrhalis </it>O35E indicated that this gene encoded the cognate immunity factor. Reverse transcriptase-PCR was used to show that the <it>mcbA</it>, <it>mcbB</it>, <it>mcbC</it>, and <it>mcbI </it>ORFs were transcriptionally linked. This four-gene cluster was subsequently shown to be present in the chromosome of several <it>M. catarrhalis </it>strains including O12E. Inactivation of the <it>mcbA</it>, <it>mcbB</it>, or <it>mcbC </it>ORFs in <it>M. catarrhalis </it>O12E eliminated the ability of this strain to inhibit the growth of <it>M. catarrhalis </it>O35E. In co-culture experiments involving a <it>M. catarrhalis </it>strain containing the <it>mcbABCI </it>locus and one which lacked this locus, the former strain became the predominant member of the culture after overnight growth in broth.</p> <p>Conclusion</p> <p>This is the first description of a bacteriocin and its cognate immunity factor produced by <it>M. catarrhalis</it>. The killing activity of the McbC protein raises the possibility that it might serve to lyse other <it>M. catarrhalis </it>strains that lack the <it>mcbABCI </it>locus, thereby making their DNA available for lateral gene transfer.</p

Chorus acceleration of radiation belt relativistic electrons during March 2013 geomagnetic storm

Abstract The recent launching of Van Allen probes provides an unprecedent opportunity to investigate variations of the radiation belt relativistic electrons. During the 17-19 March 2013 storm, the Van Allen probes simultaneously detected strong chorus waves and substantial increases in fluxes of relativistic (2 - 4.5 MeV) electrons around L = 4.5. Chorus waves occurred within the lower band 0.1-0.5fce (theelectron equatorial gyrofrequency), with a peak spectral density ∼10-4 nT 2/Hz. Correspondingly, relativistic electron fluxes increased by a factor of 102-103 during the recovery phase compared to the main phase levels. By means of a Gaussian fit to the observed chorus spectra, the drift and bounce-averaged diffusion coefficients are calculated and then used to solve a 2-D Fokker-Planck diffusion equation. Numerical simulations demonstrate that the lower-band chorus waves indeed produce such huge enhancements in relativistic electron fluxes within 15 h, fitting well with the observation. Key Points Initial RBSP correlated data of chorus waves and relativistic electron fluxes A realistic simulation to examine effect of chorus on relativistic electron flux Chorus yields huge increases inelectron flux rapidly, consistent with data

How ready is China for a China-style world order? China's state media discourse under construction

What exactly is the China-style world order that Chinese officials and intellectual elites have recently been talking about, and how ready is China for it? An examination and analysis of discourses on ‘Africa Live’ on CCTV Africa, the first overseas news center of China Central Television (CCTV), yields some highly noticeable features and significant themes, confirming that although China has shifted from a low-profile approach to a more assertive one, in an attempt to change the global order, its verbal challenge and sometimes harsh criticism of the American-led international system is accompanied by an obvious absence of a clear vision of what the new world order should be like. This lack of a clear vision may be due to the fact that the Chinese discourse on world order is still a work in progress, constrained by internal practices, and Africa is its testing ground for the construction of a discourse that China envisages as an alternative

Anticline growth by shortening during crustal exhumation of the Moroccan Atlantic margin

It is unclear how the crustal-scale erosional exhumation of continental domains of the Moroccan Atlantic margin and the excessive subsidence of its rifted domains affected the Late Jurassic-Early Cretaceous post-rift evolution of the margin. To constrain the km-scale exhumation, we study the structural evolution of the Jbel Amsittene. This anticline is located on the coastal plain of the Moroccan Atlantic margin, and is classically considered to have been developed initially in the Late Cretaceous by halokinesis, and by contraction during the Neogene. Contrarily, our structural analysis indicates that the anticline is a fault-propagation fold verging north with Triassic salts at its core and that it formed by shortening shortly after continental breakup of the Central Atlantic. The anticline grew by NNW-SSE to NNE-SSW contraction, as shown by syn-tectonic wedges, regional kinematic indicators and synsedimentary structures in Upper Jurassic to Lower Cretaceous rocks. It grew further and tightened during the Cenozoic, presumably in relation to the Atlas/Alpine contraction. Thus, our data and interpretation suggest that “tectonic-drives-salt” in the anticline early growth, which is coeval with the growth of other anticlines along the Moroccan Atlantic margin and widespread km-scale exhumation farther onshore. Anticline growth due to shortening argues for intraplate far-field stresses potentially linked to the geodynamic evolution of the African, American and European plates

Nonstorm time dynamics of electron radiation belts observed by the Van Allen Probes

Abstract Storm time electron radiation belt dynamics have been widely investigated for many years. Here we present a rarely reported nonstorm time event of electron radiation belt evolution observed by the Van Allen Probes during 21-24 February 2013. Within 2 days, a new belt centering around L=5.8 formed and gradually merged with the original outer belt, with the enhancement of relativistic electron fluxes by a factor of up to 50. Strong chorus waves (with power spectral density up to 10-4nT2/Hz) occurred in the region L\u3e5. Taking into account the local acceleration driven by these chorus waves, the two-dimensional STEERB can approximately reproduce the observed energy spectrums at the center of the new belt. These results clearly illustrate the complexity of electron radiation belt behaviors and the importance of chorus-driven local acceleration even during the nonstorm times

South-South Irregular Migration: The Impacts of China’s Informal Gold Rush in Ghana

This article examines irregular South‐South migration from China to Ghana, and the role it played in transforming livelihoods and broader developmental landscapes. It looks at the entry of approximately 50,000 Chinese migrants into the informal small‐scale gold mining sector from 2008‐2013. These migrants mainly hailed from Shanglin County in Guangxi Province. In Ghana, they formed mutually beneficial relationships with local miners, both legal and illegal, introducing machinery that substantially increased gold production. However, the legal status of Chinese miners was particularly problematic as, by law, small‐scale mining is restricted to Ghanaian citizens. In mid‐2013, President Mahama established a military task force against illegal mining, resulting in the deportation of many Chinese miners. The article examines the experiences of both Chinese migrants and Ghanaian miners. Findings are that irregular migration into an informal sector had long‐lasting impacts and played a significant role in the transformation of economic, political, and physical landscapes in Ghana

Neurochemical Changes in the Mouse Hippocampus Underlying the Antidepressant Effect of Genetic Deletion of P2X7 Receptors.

Recent investigations have revealed that the genetic deletion of P2X7 receptors (P2rx7) results in an antidepressant phenotype in mice. However, the link between the deficiency of P2rx7 and changes in behavior has not yet been explored. In the present study, we studied the effect of genetic deletion of P2rx7 on neurochemical changes in the hippocampus that might underlie the antidepressant phenotype. P2X7 receptor deficient mice (P2rx7-/-) displayed decreased immobility in the tail suspension test (TST) and an attenuated anhedonia response in the sucrose preference test (SPT) following bacterial endotoxin (LPS) challenge. The attenuated anhedonia was reproduced through systemic treatments with P2rx7 antagonists. The activation of P2rx7 resulted in the concentration-dependent release of [3H]glutamate in P2rx7+/+ but not P2rx7-/- mice, and the NR2B subunit mRNA and protein was upregulated in the hippocampus of P2rx7-/- mice. The brain-derived neurotrophic factor (BDNF) expression was higher in saline but not LPS-treated P2rx7-/- mice; the P2rx7 antagonist Brilliant blue G elevated and the P2rx7 agonist benzoylbenzoyl ATP (BzATP) reduced BDNF level. This effect was dependent on the activation of NMDA and non-NMDA receptors but not on Group I metabotropic glutamate receptors (mGluR1,5). An increased 5-bromo-2-deoxyuridine (BrdU) incorporation was also observed in the dentate gyrus derived from P2rx7-/- mice. Basal level of 5-HT was increased, whereas the 5HIAA/5-HT ratio was lower in the hippocampus of P2rx7-/- mice, which accompanied the increased uptake of [3H]5-HT and an elevated number of [3H]citalopram binding sites. The LPS-induced elevation of 5-HT level was absent in P2rx7-/- mice. In conclusion there are several potential mechanisms for the antidepressant phenotype of P2rx7-/- mice, such as the absence of P2rx7-mediated glutamate release, elevated basal BDNF production, enhanced neurogenesis and increased 5-HT bioavailability in the hippocampus

Bbookx: An automatic book creation framework

ABSTRACT As more educational resources become available online, it is possible to acquire more up-to-date knowledge and information. We propose BBookX, a novel computer facilitated system that automatically and collaboratively builds free open online books using publicly available educational resources such as Wikipedia. BBookX has two separate components: one creates an open version of existing books by linking different book chapters to Wikipedia articles, while another with an interactive user interface supports interactive realtime book creation where users are allowed to modify a generated book from explicit feedback