14 research outputs found
Transiting exoplanets from the CoRoT space mission VIII. CoRoT-7b: the first Super-Earth with measured radius
We report the discovery of very shallow (DF/F = 3.4 10-4), periodic dips in
the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite,
which we interpret as due to the presence of a transiting companion. We
describe the 3-colour CoRoT data and complementary ground-based observations
that support the planetary nature of the companion. Methods. We use CoRoT color
information, good angular resolution ground-based photometric observations in-
and out- of transit, adaptive optics imaging, near-infrared spectroscopy and
preliminary results from Radial Velocity measurements, to test the diluted
eclipsing binary scenarios. The parameters of the host star are derived from
optical spectra, which were then combined with the CoRoT light curve to derive
parameters of the companion. We examine carefully all conceivable cases of
false positives, and all tests performed support the planetary hypothesis.
Blends with separation larger than 0.40 arcsec or triple systems are almost
excluded with a 8 10-4 risk left. We conclude that, as far as we have been
exhaustive, we have discovered a planetary companion, named CoRoT-7b, for which
we derive a period of 0.853 59 +/- 3 10-5 day and a radius of Rp = 1.68 +/-
0.09 REarth. Analysis of preliminary radial velocity data yields an upper limit
of 21 MEarth for the companion mass, supporting the finding.
CoRoT-7b is very likely the first Super-Earth with a measured radius.Comment: Accepted in Astronomy and Astrophysics; typos and language
corrections; version sent to the printer w few upgrade
Transiting exoplanets from the CoRoT space mission. VIII. CoRoT-7b: the first super-Earth with measured radius
Copyright © The European Southern Observatory (ESO)Aims. We report the discovery of very shallow (ΔF/F ≈ 3.4×10−4), periodic dips in the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite, which we interpret as caused by a transiting companion. We describe the 3-colour CoRoT data and complementary ground-based observations that support the planetary nature of the companion.
Methods. We used CoRoT colours information, good angular resolution ground-based photometric observations in- and out- of transit, adaptive optics imaging, near-infrared spectroscopy, and preliminary results from radial velocity measurements, to test the diluted eclipsing binary scenarios.
The parameters of the host star were derived from optical spectra, which were then combined with the CoRoT light curve to derive parameters of the companion.
Results. We examined all conceivable cases of false positives carefully, and all the tests support the planetary hypothesis. Blends with separation >0.40'' or triple systems are almost excluded with a 8 × 10−4 risk left. We conclude that, inasmuch we have been exhaustive, we have discovered a planetary companion, named CoRoT-7b, for which we derive a period of 0.853 59 ± 3 × 10−5 day and a radius of Rp = 1.68 ± 0.09 REarth. Analysis of preliminary radial velocity data yields an upper limit of 21 MEarth for the companion mass, supporting the finding.
Conclusions. CoRoT-7b is very likely the first Super-Earth with a measured radius. This object illustrates what will probably become a common situation with missions such as Kepler, namely the need to establish the planetary origin of transits in the absence of a firm radial velocity detection and mass measurement. The composition of CoRoT-7b remains loosely constrained without a precise mass. A very high surface temperature on its irradiated face, ≈1800–2600 K at the substellar point, and a very low one, ≈50 K, on its dark face assuming no atmosphere, have been derived
Development and evaluation of a recombinant DNA vaccine candidate expressing porcine circovirus 2 structural protein
Porcine circovirus 2 (PCV2) is generally associated with the porcine circovirosis syndrome, which is considered an important disease of swine and has potentially serious economic impact on the swine industry worldwide. This article describes the construction of a recombinant plasmid expressing the PCV2 structural protein and the evaluation of cellular and humoral immune responses produced by this recombinant vaccine in BALB/c mice. The vaccine candidate was obtained and analyzed in vivo, in an effort to determine the ability to induce a specific immune response in mice. DNA was extracted from a Brazilian PCV2 isolate and the gene coding for Cap protein was amplified by PCR and inserted into an expression plasmid. Groups of BALB/c mice were inoculated intra-muscularly and intradermally in a 15-day interval, with 100 µg and 50 µg of the vaccine construct, respectively. Another group was inoculated intramuscularly with 100 µg of empty plasmid, corresponding to the control group. Seroconversion and cellular response in BALB/c mice were compared and used for vaccine evaluation. Seroconversion was analyzed by ELISA. After a series of 3 immunizations the spleen cells of the immunized animals were used to perform lymphocyte proliferation assays. Seroconversion to PCV2 was detected by ELISA in the animals inoculated with the vaccine construct when compared with control groups. Lymphocyte proliferation assays showed a stronger cell proliferation in the inoculated animals compared with the control group. Thus, the vaccine candidate construct demonstrated to be able to induce both humoral and cellular responses in inoculated mice.O circovírus suíno 2 (PCV2) é geralmente associado à síndrome da circovirose suína, que é considerada uma importante doença de suínos e possui um sério impacto econômico na suinocultura mundial. Este trabalho descreve a construção de um plasmídeo recombinante que expressa a proteína estrutural do PCV2 e a avaliação das respostas imune humoral e celular por meio de vacinação em camundongos BALB/c. O candidato vacinal foi submetido a análises in vivo, determinando a capacidade de induzir resposta imune específica em camundongos. O DNA de um isolado brasileiro de PCV2 foi extraído e o gene que codifica para a proteína do capsídeo foi amplificado por PCR e inserido num plasmídeo de expressão. Grupos de camundongos BALB/c foram inoculados por via intramuscular e intradérmica a cada 15 dias, com 100µg e 50µg da construção vacinal, respectivamente. Outro grupo foi inoculado com 100µg do plasmídeo original, correspondente ao grupo controle. A soroconversão e a resposta celular dos grupos de camundongos BALB/c vacinados foram comparados como parâmetros de avaliação vacinal. A soroconversão foi avaliada por um teste de ELISA. Após 3 imunizações, as células esplênicas dos animais imunizados foram utilizadas nos ensaios de linfoproliferação. A soroconversão para o PCV2 foi detectada por ELISA nos animais inoculados com a construção vacinal quando comparados com o grupo controle. Nos ensaios de linfoproliferação foi observada uma grande proliferação celular nos animais inoculados comparados ao grupo controle. Portanto, o candidato vacinal demonstrou ser capaz de induzir tanto uma resposta humoral e celular nos camundongos inoculados
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The Future of Real Time Telemetry Systems
International Telemetering Conference Proceedings / October 15-17, 1974 / International Hotel, Los Angeles, CaliforniaThis paper briefly outlines the development of real time data processing systems and discusses the techniques used in present systems to bring full power of computer facilities to the systems user. While discussing existing systems, future user requirements are examined and the application of recent technology to these needs is investigated. Software systems, hardware techniques and systems management are reviewed so that future systems design may be responsive to the human, as well as the technical elements of vehicle testing.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection