The 12C14N/12C15N and 12C14N/13C14N isotopic ratios have been determined in comets C/1995 O1 (Hale-Bopp), C/2001 Q4 (NEAT) and C/2003 K4 (LINEAR) at heliocentric distances of, respectively, 2.7, 3.7 ...and 2.6 AU. These ratios have also been measured at $r\sim1$ AU. No significant differences were found between all determinations, nor with the value obtained for other comets. If confirmed, the discrepancy between the nitrogen isotopic ratios from optical and millimeter measurements on CN and HCN would rule out HCN as a major parent of the cometary CN radicals.
Over the past 10 years the isotopic ratios of carbon (
12C/
13C) and nitrogen (
14N/
15N) have been determined for a dozen comets, bright enough to allow obtaining the required measurements from the ...ground. The ratios were derived from high-resolution spectra of the CN coma measured in the B
2∑
+−X
2∑
+ (0, 0) emission band around 387
nm. The observed comets belong to different dynamical classes, including dynamically new as well as long- and short-period comets from the Halley- and Jupiter-family. In some cases the comets could be observed at various heliocentric distances. All values determined for the carbon and nitrogen isotopic ratios were consistent within the error margin irrespective of the type of comet or the heliocentric distance at which it was observed. Our investigations resulted in average ratios of
12C/
13C=91±21 and nitrogen
14N/
15N=141±29. Whilst the value for the carbon isotopic ratio is in good agreement with the solar and terrestrial value of 89, the nitrogen isotopic ratio is very different from the telluric value of 272.
The 12C14N/12C15N and 12C14N/13C14N isotopic ratios are determined for the first time in a Jupiter-family comet, 88P/1981 Q1 Howell, and in the chemically peculiar Oort Cloud comet C/1999 S4 ...(LINEAR). By comparing these measurements to previous ones derived for six other Oort Cloud comets (including one of Halley-type), we find that both the carbon and nitrogen isotopic ratios are constant within the uncertainties. The mean values are 12C/13C 90 and 14N/15N for the eight comets. These results strengthen the view that CN radicals originate from refractory organics formed in the protosolar molecular cloud and subsequently incorporated in comets.
On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational ...campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics.
We report on simultaneous optical and infrared observations of the Halley Family comet 8P/Tuttle performed with the ESO Very Large Telescope. Such multi-wavelength and coordinated observations are a ...good example of what can be done to support space missions. From high resolution optical spectroscopy of the CN (0,0) 388 nm and NH
2
(0,9,0) 610 nm bands using UVES at UT2 we determined
12
C/
13
C = 90 ± 10 and
14
N/
15
N = 150 ± 20 in CN and we derived a nuclear spin temperature of NH
3
of 29 ± 1 K. These values are similar to those found in Oort-Cloud and Jupiter Family comets. From low resolution long slit spectroscopy with FORS1 at UT2 we determined the CN, C
3
and C
2
production rates and the parent and daughter scale lengths up to 5.2 10
5
km tailward. From high resolution IR spectroscopy with CRIRES at UT1 we measured simultaneously the production rates and mixing ratios of H
2
O, HCN, C
2
H
2
, CH
4
, C
2
H
6
, and CH
3
OH.
Highlights • These consensus criteria update the 2003 diagnostic criteria for RLS/WED. • A new essential criterion, differential diagnosis, improves diagnostic specificity. • The clinical ...significance of RLS/WED is determined by a new specifier. • A course specifier classifies RLS/WED as chronic-persistent or intermittent. • The pediatric diagnostic criteria have been merged with the adult criteria.
Abstract This report presents the results of the work by a joint task force of the International and European Restless Legs Syndrome Study Groups and World Association of Sleep Medicine that revised ...and updated the current standards for recording and scoring leg movements (LM) in polysomnographic recordings (PSG). First, the background of the decisions made and the explanations of the new rules are reported and then specific standard rules are presented for recording, detecting, scoring and reporting LM activity in PSG. Each standard rule has been classified with a level of evidence. At the end of the paper, Appendix 1 provides algorithms to aid implementation of these new standards in software tools. There are two main changes introduced by these new rules: 1) Candidate LM (CLM), are any monolateral LM 0.5-10 s long or bilateral LM 0.5-15 s long; 2) periodic LM (PLM) are now defined by runs of at least 4 consecutive CLM with an intermovement interval ≥10 and ≤90 s without any CLM preceded by an interval <10 s interrupting the PLM series. There are also new options defining LM associated with respiratory events. The PLM rate may now first be determined for all CLM not excluding any related to respiration (providing a consistent number across studies regardless of the rules used to define association with respiration) and, subsequently, the PLM rate should also be calculated without considering the respiratory related events. Finally, special considerations for pediatric studies are provided. The expert visual scoring of LM has only been altered by the new standards to require accepting all LM >0.5 s regardless of duration, otherwise the technician scores the LM as for the old standards. There is a new criterion for the morphology of LM that applies only to computerized LM detection to better match expert visual detection. Available automatic scoring programs will incorporate all the new rules so that the new standards should reduce technician burden for scoring PLMS.
► We study NASA Dawn target dwarf-planet (1) Ceres with SINFONI at ESO VLT. ► We acquire NIR disk-resolved spectra of Ceres, with a 75
km spatial resolution. ► Slight variations of the spectral slope ...are detected, linked with albedo markings. ► No absorption bands are detected above a 3% level. ► The surface of (1) Ceres is remarkably homogeneous at our level of resolution.
Dwarf-planet (1) Ceres is one of the two targets, along with (4) Vesta, that will be studied by the NASA Dawn spacecraft via imaging, visible and near-infrared spectroscopy, and gamma-ray and neutron spectroscopy. While Ceres’ visible and near-infrared disk-integrated spectra have been well characterized, little has been done about quantifying spectral variations over the surface. Any spectral variation would give us insights on the geographical variation of the composition and/or the surface age. The only work so far was that of Rivkin and Volquardsen (2010, Icarus 206, 327) who reported rotationally-resolved spectroscopic (disk-integrated) observations in the 2.2–4.0
μm range; their observations showed evidence for a relatively uniform surface.
Here, we report disk-resolved observations of Ceres with SINFONI (ESO VLT) in the 1.17–1.32
μm and 1.45–2.35
μm wavelength ranges. The observations were made under excellent seeing conditions (0.6″), allowing us to reach a spatial resolution of ∼75
km on Ceres’ surface. We do not find any spectral variation above a 3% level, suggesting a homogeneous surface at our spatial resolution. Slight variations (about 2%) of the spectral slope are detected, geographically correlated with the albedo markings reported from the analysis of the HST and Keck disk-resolved images of Ceres (Li et al. 2006, Icarus 182, 143; Carry et al. 2008, Astron. Astrophys. 478, 235). Given the lack of constraints on the surface composition of Ceres, however, we cannot assert the causes of these variations.
The histone acetyltransferase (HAT) enzymes p300 and CBP are closely related paralogs that serve as transcriptional coactivators and have been found to be dysregulated in cancer and other diseases. ...p300/CBP is a multidomain protein and possesses a highly conserved bromodomain that has been shown to bind acetylated Lys residues in both proteins and various small molecules, including I-CBP112 and CBP30. Here we show that the ligand I-CBP112 can stimulate nucleosome acetylation up to 3-fold while CBP30 does not. Activation of p300/CBP by I-CBP112 is not observed with the isolated histone H3 substrate but requires a nucleosome substrate. I-CBP112 does not impact nucleosome acetylation by the isolated p300 HAT domain, and the effects of I-CBP112 on p300/CBP can be neutralized by CBP30, suggesting that I-CBP112 likely allosterically activates p300/CBP through bromodomain interactions. Using mass spectrometry and Western blots, we have found that I-CBP112 particularly stimulates acetylation of Lys18 of histone H3 (H3K18) in nucleosomes, an established in vivo site of p300/CBP. In addition, we show that I-CBP112 enhances H3K18 acetylation in acute leukemia and prostate cancer cells in a concentration range commensurate with its antiproliferative effects. Our findings extend the known pharmacology of bromodomain ligands in the regulation of p300/CBP and suggest a novel approach to modulating histone acetylation in cancer.
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