6,110 research outputs found

    The separation test in vacuum of the Ariane 4 payload fairing

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    The separation tests performed during the qualification test program of the Ariane 4 Payload Fairing are described. This is the first fairing structure to be developed using carbon fiber technology. Two separation tests were performed under vacuum conditions. The primary objectives of these tests were to verify compliance with the vehicle imposed requirements and to establish the behavioral characteristics of the fairing structure itself

    Simple Phase Bias for Superconducting Circuits

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    A phase-bias tool, based on a trapped fluxoid in a ring, is proposed and demonstrated. It can provide arbitrary phase values and is simple to fabricate. The phase bias has been realized in two superconducting quantum interference devices, where the critical current versus magnetic flux is shown to be shifted by a \pi/2 and \pi.Comment: 5 pages, including 4 figures. Submitted to AP

    Stability of the proton-to-electron mass ratio

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    We report a limit on the fractional temporal variation of the proton-to-electron mass ratio as, obtained by comparing the frequency of a rovibrational transition in SF6 with the fundamental hyperfine transition in Cs. The SF6 transition was accessed using a CO2 laser to interrogate spatial 2-photon Ramsey fringes. The atomic transition was accessed using a primary standard controlled with a Cs fountain. This result is direct and model-free

    Genomic Diversity among Beijing and non-Beijing Mycobacterium tuberculosis Isolates from Myanmar

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    Background: The Beijing family of Mycobacterium tuberculosis is dominant in countries in East Asia. Genomic polymorphisms are a source of diversity within the M. tuberculosis genome and may account for the variation of virulence among M. tuberculosis isolates. Till date there are no studies that have examined the genomic composition of M. tuberculosis isolates from the high TB-burden country, Myanmar. Methodology/Principle Findings: Twenty-two M. tuberculosis isolates from Myanmar were screened on whole-genome arrays containing genes from M. tuberculosis H37Rv, M. tuberculosis CDC1551 and M. bovis AF22197. Screening identified 198 deletions or extra regions in the clinical isolates compared to H37Rv. Twenty-two regions differentiated between Beijing and non-Beijing isolates and were verified by PCR on an additional 40 isolates. Six regions (Rv0071-0074 [RD105], Rv1572-1576c [RD149], Rv1585c-1587c [RD149], MT1798-Rv1755c [RD152], Rv1761c [RD152] and Rv0279c) were deleted in Beijing isolates, of which 4 (Rv1572-1576c, Rv1585c-1587c, MT1798-Rv1755c and Rv1761c) were variably deleted among ST42 isolates, indicating a closer relationship between the Beijing and ST42 lineages. The TbD1 region, Mb1582-Mb1583 was deleted in Beijing and ST42 isolates. One M. bovis gene of unknown function, Mb3184c was present in all isolates, except 11 of 13 ST42 isolates. The CDC1551 gene, MT1360 coding for a putative adenylate cyclase, was present in all Beijing and ST42 isolates (except 1). The pks15/1 gene, coding for a putative virulence factor, was intact in all Beijing and non-Beijing isolates, except in ST42 and ST53 isolates. Conclusion: This study describes previously unreported deletions/extra regions in Beijing and non-Beijing M. tuberculosis isolates. The modern and highly frequent ST42 lineage showed a closer relationship to the hypervirulent Beijing lineage than to the ancient non-Beijing lineages. The pks15/1 gene was disrupted only in modern non-Beijing isolates. This is the first report of an in-depth analysis on the genomic diversity of M. tuberculosis isolates from Myanmar

    Long term minimum tillage investigations, Stubble management, Deep ripping

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    Direct drilling Long term minimum tillage investigations (1) Continuous cropping – 77A16, 77A18, 77MT15, 77WH17, 77WH13, 78M25. (2) Rotational cropping – 77A43, 77E52, 77M35, 77M56, 77MT51, 77WH8. Stubble management – 79M7, 79WH6, 82M34, 84M1, 82LG4, 82LG46 (82KD1). Deep ripping - 82M35 in Minimum Tillage Rotation section also contains a deep ripping treatment. 77WH17, 80A44, 80NO46, 81M45, 81NO3, 81NO4, 82GE37, 82GE38, 82M30, 82M46, 82M60, 82ME38, 82N32, 82WH49, 84E24, (84C42, 84C43, 84C44, 84C45, 84C46) Eradu Sandplain – ECRS, 84E23, 84E24, 84JE43, 84JE44, 84LG37, 84M38, 84NO58, 84WH2, 84WH3, 84WH39. Additional deep ripping research is included in summaries by W. Bowden, D. Tennant, J. Hamblin, J. Wilson

    N 1,N 2-Bis[(2-chloro-6-methyl­quinolin-3-yl)methyl­idene]ethane-1,2-diamine

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    The title mol­ecule, C24H20Cl2N4, lies on an inversion center in an extended trans conformation. In the crystal, weak C—H⋯Cl inter­actions connect the mol­ecules into chains along [010]

    Preliminary analysis of a wake trailing a spacecraft

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    Using void regions trailing orbiting bodies to conserve propellant of untethered modules flying in formation with mother spacecraf
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