1,937 research outputs found

    An experimental model of a 2kw, 2500 volt power converter for ion thrustors using gate controlled switches in two phase-shifted parallel inverters summary report

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    Power converter for ion thrustors using electronic gate controlled switches in two phase-shifted parallel inverter

    Wave Structures and Nonlinear Balances in a Family of 1+1 Evolutionary PDEs

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    We study the following family of evolutionary 1+1 PDEs that describe the balance between convection and stretching for small viscosity in the dynamics of 1D nonlinear waves in fluids: m_t + \underbrace{um_x \} _{(-2mm)\hbox{convection}(-2mm)} + \underbrace{b u_xm \} _{(-2mm)\hbox{stretching}(-2mm)} = \underbrace{\nu m_{xx}\ }_{(-2mm)\hbox{viscosity}}, \quad\hbox{with}\quad u=g*m . Here u=g∗mu=g*m denotes u(x)=∫−∞∞g(x−y)m(y)dy. u(x)=\int_{-\infty}^\infty g(x-y)m(y) dy . We study exchanges of stability in the dynamics of solitons, peakons, ramps/cliffs, leftons, stationary solutions and other solitary wave solutions associated with this equation under changes in the nonlinear balance parameter bb.Comment: 69 pages, 26 figure

    Alien Registration- Richard, Staley F. (Brunswick, Cumberland County)

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    https://digitalmaine.com/alien_docs/31657/thumbnail.jp

    A canonical FtsZ protein in Verrucomicrobium spinosum, a member of the Bacterial phylum Verrucomicrobia that also includes tubulin-producing Prosthecobacter species

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    BACKGROUND: The origin and evolution of the homologous GTP-binding cytoskeletal proteins FtsZ typical of Bacteria and tubulin characteristic of eukaryotes is a major question in molecular evolutionary biology. Both FtsZ and tubulin are central to key cell biology processes – bacterial septation and cell division in the case of FtsZ and in the case of tubulins the function of microtubules necessary for mitosis and other key cytoskeleton-dependent processes in eukaryotes. The origin of tubulin in particular is of significance to models for eukaryote origins. Most members of domain Bacteria possess FtsZ, but bacteria in genus Prosthecobacter of the phylum Verrucomicrobia form a key exception, possessing tubulin homologs BtubA and BtubB. It is therefore of interest to know whether other members of phylum Verrucomicrobia possess FtsZ or tubulin as their FtsZ-tubulin gene family representative. RESULTS: Verrucomicrobium spinosum, a member of Phylum Verrucomicrobia of domain Bacteria, has been found to possess a gene for a protein homologous to the cytoskeletal protein FtsZ. The deduced amino acid sequence has sequence signatures and predicted secondary structure characteristic for FtsZ rather than tubulin, but phylogenetic trees and sequence analysis indicate that it is divergent from all other known FtsZ sequences in members of domain Bacteria. The FtsZ gene of V. spinosum is located within a dcw gene cluster exhibiting gene order conservation known to contribute to the divisome in other Bacteria and comparable to these clusters in other Bacteria, suggesting a similar functional role. CONCLUSION: Verrucomicrobium spinosum has been found to possess a gene for a protein homologous to the cytoskeletal protein FtsZ. The results suggest the functional as well as structural homology of the V. spinosum FtsZ to the FtsZs of other Bacteria implying its involvement in cell septum formation during division. Thus, both bacteria-like FtsZ and eukaryote-like tubulin cytoskeletal homologs occur in different species of the phylum Verrucomicrobia of domain Bacteria, a result with potential major implications for understanding evolution of tubulin-like cytoskeletal proteins and the origin of eukaryote tubulins

    Properties and preparation of ceramic insulators for spark plugs

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    Report describes in detail the preliminary experiments which were made on the conductivity of spark-plug insulators in order to develop a satisfactory comparative method for testing various spark-plug materials. Materials tested were cements, porcelain, feldspar, and quartz

    Real Time Global Tests of the ALICE High Level Trigger Data Transport Framework

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    The High Level Trigger (HLT) system of the ALICE experiment is an online event filter and trigger system designed for input bandwidths of up to 25 GB/s at event rates of up to 1 kHz. The system is designed as a scalable PC cluster, implementing several hundred nodes. The transport of data in the system is handled by an object-oriented data flow framework operating on the basis of the publisher-subscriber principle, being designed fully pipelined with lowest processing overhead and communication latency in the cluster. In this paper, we report the latest measurements where this framework has been operated on five different sites over a global north-south link extending more than 10,000 km, processing a ``real-time'' data flow.Comment: 8 pages 4 figure

    Serological evidence of Q fever in cattle in Malawi

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    The serological prevalence of Coxiella burnetii in cattle in Malawi is unknown. Serum samples from 200 Malawian zebu cattle were tested for C. burnetii antibodies using the complement fixation test. The percentage of positive and suspicious titres was 1,5 % and 5 % respectively.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201
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