974 resultados para minor planets, asteroids


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We report the detection of WASP-35b, a planet transiting a metal-poor ([Fe/H] = -0.15) star in the Southern hemisphere, WASP-48b, an inflated planet which may have spun-up its slightly evolved host star of 1.75 R sun in the Northern hemisphere, and the independent discovery of HAT-P-30b/WASP-51b, a new planet in the Northern hemisphere. Using WASP, RISE, Faulkes Telescope South, and TRAPPIST photometry, with CORALIE, SOPHIE, and NOT spectroscopy, we determine that WASP-35b has a mass of 0.72 ± 0.06 MJ and radius of 1.32 ± 0.05RJ , and orbits with a period of 3.16 days, WASP-48b has a mass of 0.98 ± 0.09 MJ , radius of 1.67 ± 0.10 RJ , and orbits in 2.14 days, while HAT-P-30b/WASP-51b, with an orbital period of 2.81 days, is found to have a mass of 0.76 ± 0.05 MJ and radius of 1.42 ± 0.03 RJ , agreeing with values of 0.71 ± 0.03 MJ and 1.34 ± 0.07 RJ reported for HAT-P-30b.

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In this study the design and development of two real-time PCR assays for the rapid, sensitive and specific detection of infectious laryngotracheitis virus (ILTV) DNA is described. A Primer-Probe Energy Transfer (PriProET) assay and 5' conjugated Minor Groove Binder (MGB) method are compared and contrasted. Both have been designed to target the thymidine kinase gene of the ILTV genome. Both PriProET and MGB assays are capable of detecting 20 copies of a DNA standard per reaction and are linear from 2 x 10(8) to 2 x 10(2) copies/mu l. Neither PriProET, nor MGB reacted with heterologous herpesviruses, indicating a high specificity of the two methods as novel tools for virus detection and identification. This study demonstrates the suitability of PriProET and 5' conjugated MGB probes as real-time PCR chemistries for the diagnosis of respiratory diseases caused by ILTV. (C) 2011 Elsevier B.V. All rights reserved.

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A novel assay for the pan-serotypic detection of foot-and-mouth disease virus (FMDV) was designed using a 5' conjugated minor groove binder (MGB) probe real-time RT-PCR system. This assay targets the 3D region of the FMDV genome and is capable of detecting 20 copies of a transcribed RNA standard. The linear range of the test was eight logs from 2 x 10(1) to 2 x 10(8) copies and amplification time was approximately 2 h. Using a panel of 83 RNA samples from representative FMDV isolates, the diagnostic sensitivity of this test was shown to be equivalent to a TaqMan real-time RT-PCR that targets the 5' untranslated region of FMDV. Furthermore, the assay does not detect viruses causing similar clinical diseases in pigs such as swine vesicular disease virus and vesicular stomatitis virus, nor does it detect marine caliciviruses causing vesicular exanthema. The development of this assay provides a useful tool for the differential diagnosis of FMD, potentially for use in statutory or emergency testing programmes, or for detection of FMDV RNA in research applications. (C) 2011 Elsevier B.V. All rights reserved.

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The design and development of a 5' conjugated minor groove binder (MGB) probe real-time RT-PCR assay are described for rapid, sensitive and specific detection of swine vesicular disease virus (SVDV) RNA. The assay is designed to target the 2C gene of the SVDV genome and is capable of detecting 2 x 10(2) copies of an RNA standard per reaction. It does not detect any of the other RNA viruses that cause vesicular disease in pigs, or the human enterovirus, Coxsackie B5 virus (CVB5) which is closely related antigenically to SVDV. The linear range of this test was from 2 x 10(2) to 2 x 10(8) copies/mu l. The assay is rapid and can detect SVDV RNA in just over 3.5 h including the time required for nucleic acid extraction. The development of this assay provides a useful tool for the differential diagnosis of SVD or for the detection of SVDV in research applications. This study demonstrates the suitability of MGB probes as a real-time PCR chemistry for the diagnosis of swine vesicular disease. (C) 2010 Elsevier B.V. All rights reserved.

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The design of a 5' conjugated minor groove binder (MGB) probe real-time PCR assay is described for the rapid, sensitive and specific detection of African swine fever virus (ASFV) DNA. The assay is designed against the 9GL region and is capable of detecting 20 copies of a DNA standard. It does not detect any of the other common swine DNA viruses tested in this study. The assay can detect ASFV DNA in a range of clinical samples. Sensitivity was equivalent to the Office International des Epizooties (OIE) recommended TaqMan assay. In addition the assay was found to have a detection limit 10-fold more sensitive than the conventional PCR recommended by the OIE. Linear range was ten logs from 2 x 10(1) to 2 x 10(10). The assay is rapid with an amplification time just over 2 h. The development of this assay provides a useful tool for the specific diagnosis of ASF in statutory or emergency testing programs or for the detection of ASFV DNA in research applications. (C) 2010 Elsevier B.V. All rights reserved.

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The opportunistic bacterium Burkholderia cenocepacia C5424 contains two catalase/peroxidase genes, katA and katB. To investigate the functions of these genes, katA and katB mutants were generated by targeted integration of suicide plasmids into the katA and katB genes. The catalase/peroxidase activity of the katA mutant was not affected as compared with that of the parental strain, while no catalase/peroxidase activity was detected in the katB mutant. However, the katA mutant displayed reduced resistance to hydrogen peroxide under iron limitation, while the katB mutant showed hypersensitivity to hydrogen peroxide, and reduced growth under all conditions tested. The katA mutant displayed reduced growth only in the presence of carbon sources that are metabolized through the tricarboxylic acid (TCA) cycle, as the growth defect was abrogated in cultures supplemented with glucose or glycerol. This phenotype was also correlated with a marked reduction in aconitase activity. In contrast, aconitase activity was not reduced in the katB mutant and parental strains. The authors conclude that the KatA protein is a specialized catalase/peroxidase that has a novel function by contributing to maintain the normal activity of the TCA cycle, while KatB is a classical catalase/peroxidase that plays a global role in cellular protection against oxidative stress.

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We present the discovery of four new transiting hot jupiters, detected mainly from SuperWASP-North and SOPHIE observations. These new planets, WASP-52b, WASP-58b, WASP-59b, and WASP-60b, have orbital periods ranging from 1.7 to 7.9 days, masses between 0.46 and 0.94 M_Jup, and radii between 0.73 and 1.49 R_Jup. Their G1 to K5 dwarf host stars have V magnitudes in the range 11.7-13.0. The depths of the transits are between 0.6 and 2.7%, depending on the target. With their large radii, WASP-52b and 58b are new cases of low-density, inflated planets, whereas WASP-59b is likely to have a large, dense core. WASP-60 shows shallow transits. In the case of WASP-52 we also detected the Rossiter-McLaughlin anomaly via time-resolved spectroscopy of a transit. We measured the sky-projected obliquity lambda = 24 (+17/-9) degrees, indicating that WASP-52b orbits in the same direction as its host star is rotating and that this prograde orbit is slightly misaligned with the stellar equator. These four new planetary systems increase our statistics on hot jupiters, and provide new targets for follow-up studies.

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There are currently a number of different methods available to obtain anaesthesia in minor dermatological procedures. Although intradermal infiltration of 1% lidocaine is the favoured method for anaesthesia induction in laceration repair, it can cause significant pain in itself. Topical anaesthesia has been investigated as an alternative to infiltration anaesthesia, with the majority of studies looking at preparations of either TAC (tetracaine, adrenaline and cocaine) or LAT (lidocaine, adrenaline and tetracaine).

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There has been a long-standing discussion in the literature as to whether core accretion or disk instability is the dominant mode of planet formation. Over the last decade, several lines of evidence have been presented showing that core accretion is most likely the dominant mechanism for the close-in population of planets probed by radial velocity and transits. However, this does not by itself prove that core accretion is the dominant mode for the total planet population, since disk instability might conceivably produce and retain large numbers of planets in the far-out regions of the disk. If this is a relevant scenario, then the outer massive disks of B-stars should be among the best places for massive planets and brown dwarfs to form and reside. In this study, we present high-contrast imaging of 18 nearby massive stars of which 15 are in the B2-A0 spectral-type range and provide excellent sensitivity to wide companions. By comparing our sensitivities to model predictions of disk instability based on physical criteria for fragmentation and cooling, and using Monte Carlo simulations for orbital distributions, we find that ~85% of such companions should have been detected in our images on average. Given this high degree of completeness, stringent statistical limits can be set from the null-detection result, even with the limited sample size. We find that

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We present three newly discovered sub-Jupiter mass planets from the SuperWASP survey: WASP-54b is a heavily bloated planet of mass 0.636$^{+0.025}_{-0.024}$ \mj and radius 1.653$^{+0.090}_{-0.083}$ \rj. It orbits a F9 star, evolving off the main sequence, every 3.69 days. Our MCMC fit of the system yields a slightly eccentric orbit ($e=0.067^{+0.033}_{-0.025}$) for WASP-54b. We investigated further the veracity of our detection of the eccentric orbit for WASP-54b, and we find that it could be real. However, given the brightness of WASP-54 V=10.42 magnitudes, we encourage observations of a secondary eclipse to draw robust conclusions on both the orbital eccentricity and the thermal structure of the planet. WASP-56b and WASP-57b have masses of 0.571$^{+0.034}_{-0.035}$ \mj and $0.672^{+0.049}_{-0.046}$ \mj, respectively; and radii of $1.092^{+0.035}_{-0.033}$ \rj for WASP-56b and $0.916^{+0.017}_{-0.014}$ \rj for WASP-57b. They orbit main sequence stars of spectral type G6 every 4.67 and 2.84 days, respectively. WASP-56b and WASP-57b show no radius anomaly and a high density possibly implying a large core of heavy elements; possibly as high as $\sim$50 M$_{\oplus}$ in the case of WASP-57b. However, the composition of the deep interior of exoplanets remain still undetermined. Thus, more exoplanet discoveries such as the ones presented in this paper, are needed to understand and constrain giant planets' physical properties.

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We have calculated 90% confidence limits on the steady-state rate of catastrophic disruptions of main belt asteroids in terms of the absolute magnitude at which one catastrophic disruption occurs per year  as a function of the post-disruption increase in brightness (Δm) and subsequent brightness decay rate (τ  ). The confidence limits were calculated using the brightest unknown main belt asteroid (V=18.5) detected with the Pan-STARRS1 (Pan-STARRS1) telescope. We measured the Pan-STARRS1’s catastrophic disruption detection efficiency over a 453-day interval using the Pan-STARRS moving object processing system (MOPS) and a simple model for the catastrophic disruption event’s photometric behavior in a small aperture centered on the catastrophic disruption event. We then calculated the  contours in the ranges from  and  encompassing measured values from known cratering and disruption events and our model’s predictions. Our simplistic catastrophic disruption model suggests that  and  which would imply that H0≳28—strongly inconsistent withH0,B2005=23.26±0.02 predicted by Bottke et al. (Bottke, W.F., Durda, D.D., Nesvorný, D., Jedicke, R., Morbidelli, A., Vokrouhlický, D., Levison, H.F. [2005]. Icarus, 179, 63–94.) using purely collisional models. However, if we assume that H0=H0,B2005 our results constrain , inconsistent with our simplistic impact-generated catastrophic disruption model. We postulate that the solution to the discrepancy is that >99% of main belt catastrophic disruptions in the size range to which this study was sensitive (∼100 m) are not impact-generated, but are instead due to fainter rotational breakups, of which the recent discoveries of disrupted asteroids P/2013 P5 and P/2013 R3 are probable examples. We estimate that current and upcoming asteroid surveys may discover up to 10 catastrophic disruptions/year brighter than V=18.5.

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Linguistic influences in mathematics have previously been explored throughsubtyping methodology and by taking advantage of the componential nature ofmathematics and variations in language requirements that exist across tasks. Thepresent longitudinal investigation aimed to examine the language requirements of mathematical tasks in young children aged 5-7 years. Initially, 256 children were screened for mathematics and reading difficulties using standardised measures. Those scoring at or below the 35th percentile on either dimension were classified as having difficulty. From this screening, 115 children were allocated to each of the MD (n=26), MDRD (n=32), reading difficulty (RD, n=22) and typically achieving (TA, n=35) subtypes. These children were tested at four time points, separated by six monthly intervals, on a battery of seven mathematical tasks. Growth curve analysis indicated that, in contrast to previous research on older children, young children with MD and MDRD had very similar patterns of development on all mathematical tasks. Overall, the subtype comparisons suggested that language played only a minor mediating role in most tasks, and this was secondary in importance to non-verbal skills. Correlational evidence suggested that children from the different subtypescould have been using different mixes of verbal and non-verbal strategies to solve the mathematical problems.

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Myeloproliferative neoplasms (MPNs) are rare diseases that include classic entities; polycythaemia vera, essential thrombocythaemia and primary myelofibrosis. In this short report, minor allele frequencies of common MPN mutations are compared between the Irish blood donor population and other populations of European descent using data from the Haplotype Map project. The Affymetrix array 6.0 platform was utilised identifying nine single nucleotide polymorphisms (SNPs) and six proxy SNPs. The variability of allele frequencies for MPN mutations could account for the different incidence rates seen between populations of European ancestry, giving a better understanding of the genetic predisposition to MPNs. 

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We present VLT+VISIR mid-IR observations of fast-rotating near-Earth asteroids. Diameters and albedos are determined with thermal models. These NEAs may have unusual surface properties, e.g. from regolith transport/stripping due to the YORP effect.