Are Debris Disks and Massive Planets Correlated?

Using data from the Spitzer Space Telescope Legacy Science Program ``Formation and Evolution of Planetary Systems'' (FEPS), we have searched for debris disks around 9 FGK stars (2-10 Gyr), known from radial velocity (RV) studies to have one or more massive planets. Only one of the sources, HD 38529, has excess emission above the stellar photosphere; at 70 micron the signal-to-noise ratio in the excess is 4.7 while at wavelengths < 30 micron there is no evidence of excess. The remaining sources show no excesses at any Spitzer wavelengths. Applying survival tests to the FEPS sample and the results for the FGK survey published in Bryden et al. (2006), we do not find a significant correlation between the frequency and properties of debris disks and the presence of close-in planets. We discuss possible reasons for the lack of a correlation.Comment: 24 pages, 3 figures. Accepted to Astrophysical Journa

The Complete Census of 70-um-Bright Debris Disks within the FEPS (Formation and Evolution of Planetary Systems) Spitzer Legacy Survey of Sun-like Stars

(abbreviated) We report detection with the Spitzer Space Telescope of cool dust surrounding solar type stars. The observations were performed as part of the Legacy Science Program, ``Formation and Evolution of Planetary Systems'' (FEPS). From the overall FEPS sample (Meyer et al. 2006) of 328 stars having ages ~0.003-3 Gyr we have selected sources with 70 um flux densities indicating excess in their spectral energy distributions above expected photospheric emission........ .....The rising spectral energy distributions towards - and perhaps beyond - 70 um imply dust temperatures T_dust <45-85 K for debris in equilibrium with the stellar radiation field. We infer bulk properties such as characteristic temperature, location, fractional luminosity, and mass of the dust from fitted single temperature blackbody models. For >1/3 of the debris sources we find that multiple temperature components are suggested, implying a spatial distribution of dust extending over many tens of AU. Because the disks are dominated by collisional processes, the parent body (planetesimal) belts may be extended as well. Preliminary assessment of the statistics of cold debris around sun-like stars shows that ~10% of FEPS targets with masses between 0.6 and 1.8 Msun and ages between 30 Myr and 3 Gyr exhibit 70 um emission in excess of the expected photospheric flux density. We find that fractional excess amplitudes appear higher for younger stars and that there may be a trend in 70 um excess frequency with stellar mass.Comment: article accepted to Ap

Formation and Evolution of Planetary Systems: Placing Our Solar System in Context with Spitzer

We summarize the progress to date of our Legacy Science Program entitled "The Formation and Evolution of Planetary Systems" (FEPS) based on observations obtained with the Spitzer Space Telescope during its first year of operation. In addition to results obtained from our ground-based preparatory program and our early validation program, we describe new results from a survey for near-infrared excess emission from the youngest stars in our sample as well as a search for cold debris disks around sun-like stars. We discuss the implications of our findings with respect to current understanding of the formation and evolution of our own solar system.Comment: 8 postscript pages including 3 figures. To appear in "Spitzer New Views of the Cosmos" ASP Conference Series, eds. L. Armus et al. FEPS website at http://feps.as.arizona.ed

Spitzer Observations of G Dwarfs in the Pleiades: Circumstellar Debris Disks at 100 Myr Age

Fluxes and upper limits in the wavelength range from 3.6 to 70 microns from the Spitzer Space Telescope are provided for twenty solar-mass Pleiades members. One of these stars shows a probable mid-IR excess and two others have possible excesses, presumably due to circumstellar debris disks. For the star with the largest, most secure excess flux at MIPS wavelengths, HII1101, we derive Log(L[dust]/L[Sun]) ~ -3.8 and an estimated debris disk mass of 4.2 x 10^-5 M(Earth) for an assumed uniform dust grain size of 10 microns If the stars with detected excesses are interpreted as stars with relatively recent, large collision events producing a transient excess of small dust particles, the frequency of such disk transients is about ~ 10 % for our ~ 100 Myr, Pleiades G dwarf sample. For the stars without detected 24-70 micron excesses, the upper limits to their fluxes correspond to approximate 3 sigma upper limits to their disk masses of 6 x 10^-6 M(Earth) using the MIPS 24 micron upper limit, or 2 x 10^-4 M(Earth) using the MIPS 70 micron limit. These upper limit disk masses (for "warm" and "cold" dust, respectively) are roughly consistent, but somewhat lower than, predictions of a heuristic model for the evolution of an "average" solar-mass star's debris disk based on extrapolation backwards in time from current properties of the Sun's Kuiper belt.Comment: 32 postscript pages including 8 figues and 3 tables. To appear in the Astronomical Journa

Feedback from the heart: emotional learning and memory is controlled by cardiac cycle, interoceptive accuracy and personality

Feedback processing is critical to trial-and-error learning. Here, we examined whether interoceptive signals concerning the state of cardiovascular arousal influence the processing of reinforcing feedback during the learning of ‘emotional’ face-name pairs, with subsequent effects on retrieval. Participants (N = 29) engaged in a learning task of face-name pairs (fearful, neutral, happy faces). Correct and incorrect learning decisions were reinforced by auditory feedback, which was delivered either at cardiac systole (on the heartbeat, when baroreceptors signal the contraction of the heart to the brain), or at diastole (between heartbeats during baroreceptor quiescence). We discovered a cardiac influence on feedback processing that enhanced the learning of fearful faces in people with heightened interoceptive ability. Individuals with enhanced accuracy on a heartbeat counting task learned fearful face-name pairs better when feedback was given at systole than at diastole. This effect was not present for neutral and happy faces. At retrieval, we also observed related effects of personality: First, individuals scoring higher for extraversion showed poorer retrieval accuracy. These individuals additionally manifested lower resting heart rate and lower state anxiety, suggesting that attenuated levels of cardiovascular arousal in extraverts underlies poorer performance. Second, higher extraversion scores predicted higher emotional intensity ratings of fearful faces reinforced at systole. Third, individuals scoring higher for neuroticism showed higher retrieval confidence for fearful faces reinforced at diastole. Our results show that cardiac signals shape feedback processing to influence learning of fearful faces, an effect underpinned by personality differences linked to psychophysiological arousal

Epigenetic Silencing of Spermatocyte-Specific and Neuronal Genes by SUMO Modification of the Transcription Factor Sp3

SUMO modification of transcription factors is linked to repression of transcription. The physiological significance of SUMO attachment to a particular transcriptional regulator, however, is largely unknown. We have employed the ubiquitously expressed murine transcription factor Sp3 to analyze the role of SUMOylation in vivo. We generated mice and mouse embryonic fibroblasts (MEFs) carrying a subtle point mutation in the SUMO attachment sequence of Sp3 (IKEE553D mutation). The E553D mutation impedes SUMOylation of Sp3 at K551 in vivo, without affecting Sp3 protein levels. Expression profiling revealed that spermatocyte-specific genes, such as Dmc1 and Dnahc8, and neuronal genes, including Paqr6, Rims3, and Robo3, are de-repressed in non-testicular and extra-neuronal mouse tissues and in mouse embryonic fibroblasts expressing the SUMOylation-deficient Sp3E553D mutant protein. Chromatin immunoprecipitation experiments show that transcriptional de-repression of these genes is accompanied by the loss of repressive heterochromatic marks such as H3K9 and H4K20 tri-methylation and impaired recruitment of repressive chromatin-modifying enzymes. Finally, analysis of the DNA methylation state of the Dmc1, Paqr6, and Rims3 promoters by bisulfite sequencing revealed that these genes are highly methylated in Sp3wt MEFs but are unmethylated in Sp3E553D MEFs linking SUMOylation of Sp3 to tissue-specific CpG methylation. Our results establish SUMO conjugation to Sp3 as a molecular beacon for the assembly of repression machineries to maintain tissue-specific transcriptional gene silencing

The impact of MTHFR 677C → T risk knowledge on changes in folate intake: findings from the Food4Me study

Background It is hypothesised that individuals with knowledge of their genetic risk are more likely to make health-promoting dietary and lifestyle changes. The present study aims to test this hypothesis using data from the Food4Me study. This was a 6-month Internet-based randomised controlled trial conducted across seven centres in Europe where individuals received either general healthy eating advice or varying levels of personalised nutrition advice. Participants who received genotype-based personalised advice were informed whether they had the risk (CT/TT) (n = 178) or non-risk (CC) (n = 141) alleles of the methylenetetrahydrofolate reductase (MTHFR) gene in relation to cardiovascular health and the importance of a sufficient intake of folate. General linear model analysis was used to assess changes in folate intake between the MTHFR risk, MTHFR non-risk and control groups from baseline to month 6 of the intervention. Results There were no differences between the groups for age, gender or BMI. However, there was a significant difference in country distribution between the groups (p = 0.010). Baseline folate intakes were 412 ± 172, 391 ± 190 and 410 ± 186 μg per 10 MJ for the risk, non-risk and control groups, respectively. There were no significant differences between the three groups in terms of changes in folate intakes from baseline to month 6. Similarly, there were no changes in reported intake of food groups high in folate. Conclusions These results suggest that knowledge of MTHFR 677C → T genotype did not improve folate intake in participants with the risk variant compared with those with the non-risk variant

The Need for Laboratory Measurements and Ab Initio Studies to Aid Understanding of Exoplanetary Atmospheres

We are now on a clear trajectory for improvements in exoplanet observations that will revolutionize our ability to characterize their atmospheric structure, composition, and circulation, from gas giants to rocky planets. However, exoplanet atmospheric models capable of interpreting the upcoming observations are often limited by insufficiencies in the laboratory and theoretical data that serve as critical inputs to atmospheric physical and chemical tools. Here we provide an up-to-date and condensed description of areas where laboratory and/or ab initio investigations could fill critical gaps in our ability to model exoplanet atmospheric opacities, clouds, and chemistry, building off a larger 2016 white paper, and endorsed by the NAS Exoplanet Science Strategy report. Now is the ideal time for progress in these areas, but this progress requires better access to, understanding of, and training in the production of spectroscopic data as well as a better insight into chemical reaction kinetics both thermal and radiation-induced at a broad range of temperatures. Given that most published efforts have emphasized relatively Earth-like conditions, we can expect significant and enlightening discoveries as emphasis moves to the exotic atmospheres of exoplanets.Comment: Submitted as an Astro2020 Science White Pape

Endocrine disruptors and spontaneous premature labor: a case control study

<p>Abstract</p> <p>Background</p> <p>Premature labor is a poorly understood condition. Estrogen is thought to play a key role and therefore the labor process may be affected by endocrine disruptors. We sought to determine whether or not an environmental toxicant, DDE, or dietary derived endocrine disruptors, daidzein and genistein, are associated with spontaneous preterm labor.</p> <p>Methods</p> <p>Cases were defined as primiparous patients having a preterm delivery at or before 35 weeks following the spontaneous onset of labor. Controls were defined as primiparous women who delivered on the same day as the cases but at term gestation.</p> <p>Over approximately 1 year, 26 cases and 52 controls were recruited. Subjects agreed to have blood tests on day one postpartum for DDE and for the phytoestrogens genistein and daidzein.</p> <p>Results</p> <p>The mean concentration of DDE was similar in the case and control groups: 4.29 vs 4.32 ng/g lipid p = .85. In the case group, 13/26 had detectable levels of daidzein (range 0.20 – 1.56 ng/ml) compared to 25/52 controls (range 0.21 – 3.26 ng/ml). The mean concentration of daidzein was similar in cases compared to controls: 0.30 vs .34 ng/ml p = 0.91. Of the case group,14/26 had detectable levels of genistein (range 0.20 – 2.19 ng/ml) compared to 32/52 controls (range 0.21 – 2.55 ng/ml). The mean concentration of genistein was similar in cases compared to controls: 0.39 vs 0.31 ng/ml, p = 0.61.</p> <p>Conclusion</p> <p>The serum levels of DDE in this population were found to be low.</p> <p>There appears to be no relationship between serum concentrations of DDE, daidzein, and genistein and spontaneous preterm labor in our population. The inability to identify an effect may be related to the comparatively low concentrations of DDE in our population and the rapid and variable reduction of phytoestrogens from women in labor.</p

Genomic profiling of CHEK2*1100delC-mutated breast carcinomas

Background: CHEK2*1100delC is a moderate-risk breast cancer susceptibility allele with a high prevalence in the Netherlands. We performed copy number and gene expression profiling to investigate whether CHEK2*1100delC breast cancers harbor characteristic genomic aberrations, as seen for BRCA1 mutated breast cancers. Methods: We performed high-resolution SNP array and gene expression profiling of 120 familial breast carcinomas selected from a larger cohort of 155 familial breast tumors, including BRCA1, BRCA2, and CHEK2 mutant tumors. Gene expression analyses based on a mRNA immune signature was used to identify samples with relative low amounts of tumor infiltrating lymphocytes (TILs), which were previously found to disturb tumor copy number and LOH (loss of heterozygosity) profiling. We specifically compared the genomic and gene expression profiles of CHEK2*1100delC breast cancers (n = 14) with BRCAX (familial non-BRCA1/BRCA2/CHEK2*1100delC mutated) breast cancers (n = 34) of the luminal intrinsic subtypes for which both SNP-array and gene expression data is available. Results: High amounts of TILs were found in a relatively small number of luminal breast cancers as compared to breast cancers of the basal-like subtype. As expected, the