Creating a 3D microbial and chemical snapshot of a human habitat

Kapono CA, Morton JT, Bouslimani A, et al. Creating a 3D microbial and chemical snapshot of a human habitat. Scientific Reports. 2018;8(1): 3669

SOPHIE velocimetry of Kepler transit candidates VII. A false-positive rate of 35% for Kepler close-in giant exoplanet candidates

The false-positive probability (FPP) of Kepler transiting candidates is a key value for statistical studies of candidate properties. A previous investigation of the stellar population in the Kepler field has provided an estimate for the FPP of less than 5% for most of the candidates. We report here the results of our radial velocity observations on a sample of 46 Kepler candidates with a transit depth greater than 0.4%, orbital period less than 25 days and host star brighter than Kepler magnitude 14.7. We used the SOPHIE spectrograph mounted on the 1.93-m telescope at the Observatoire de Haute-Provence to establish the nature of the transiting candidates. In this sample, we found five undiluted eclipsing binaries, two brown dwarfs, six diluted eclipsing binaries, and nine new transiting planets that complement the 11 already published planets. The remaining 13 candidates were not followed-up or remain unsolved due to photon noise limitation or lack of observations. From these results we computed the FPP for Kepler close-in giant candidates to be 34.8% \pm 6.5%. We aimed to investigate the variation of the FPP for giant candidates with the longer orbital periods and found that it should be constant for orbital periods between 10 and 200 days. This significant disagrees with the previous estimates. We discuss the reasons for this discrepancy and the possible extension of this work toward smaller planet candidates. Finally, taking the false-positive rate into account, we refined the occurrence rate of hot jupiters from the Kepler data.Comment: Accepted in A&A. 16 pages including 4 online material pages. 6 figures and 1 tabl

A review of elliptical and disc galaxy structure, and modern scaling laws

A century ago, in 1911 and 1913, Plummer and then Reynolds introduced their models to describe the radial distribution of stars in `nebulae'. This article reviews the progress since then, providing both an historical perspective and a contemporary review of the stellar structure of bulges, discs and elliptical galaxies. The quantification of galaxy nuclei, such as central mass deficits and excess nuclear light, plus the structure of dark matter halos and cD galaxy envelopes, are discussed. Issues pertaining to spiral galaxies including dust, bulge-to-disc ratios, bulgeless galaxies, bars and the identification of pseudobulges are also reviewed. An array of modern scaling relations involving sizes, luminosities, surface brightnesses and stellar concentrations are presented, many of which are shown to be curved. These 'redshift zero' relations not only quantify the behavior and nature of galaxies in the Universe today, but are the modern benchmark for evolutionary studies of galaxies, whether based on observations, N-body-simulations or semi-analytical modelling. For example, it is shown that some of the recently discovered compact elliptical galaxies at 1.5 < z < 2.5 may be the bulges of modern disc galaxies.Comment: Condensed version (due to Contract) of an invited review article to appear in "Planets, Stars and Stellar Systems"(www.springer.com/astronomy/book/978-90-481-8818-5). 500+ references incl. many somewhat forgotten, pioneer papers. Original submission to Springer: 07-June-201

Lethal trap created by adaptive evolutionary response to an exotic resource

International audienceGlobal transport of organisms by humans provides novel resources to wild species, which often respond maladaptively. Native herbivorous insects have been killed feeding on toxic exotic plants, which acted as ‘ecological traps’1,2,3,4. We document a novel ‘eco-evolutionary trap’ stemming from the opposite effect; that is, high fitness on an exotic resource despite lack of adaptation to it. Plantago lanceolata was introduced to western North America by cattle-ranching. Feeding on this exotic plant released a large, isolated population of the native butterfly Euphydryas editha from a longstanding trade-off between maternal fecundity and offspring mortality. Because of this release—and despite a reduced insect developmental rate when feeding on this exotic—Plantago immediately supported higher larval survival than did the insects’ traditional host, Collinsia parviflora5. Previous work from the 1980s documented an evolving preference for Plantago by ovipositing adults6. We predicted that if this trend continued the insects could endanger themselves, because the availability of Plantago to butterflies is controlled by humans, who change land management practices faster than butterflies evolve6. Here we report the fulfilment of this prediction. The butterflies abandoned Collinsia and evolved total dependence on Plantago. The trap was set. In 2005, humans withdrew their cattle, springing the trap. Grasses grew around the Plantago, cooling the thermophilic insects, which then went extinct. This local extinction could have been prevented if the population had retained partial use of Collinsia, which occupied drier microhabitats unaffected by cattle removal. The flush of grasses abated quickly, rendering the meadow once again suitable for Euphydryas feeding on either host, but no butterflies were observed from 2008 to 2012. In 2013–2014, the site was naturally recolonized by Euphydryas feeding exclusively on Collinsia, returning the system to its starting point and setting the stage for a repeat of the anthropogenic evolutionary cycle

Choosing between conciliatory and oppositional leaders:The role of out-group signals and in-group leader candidates’ collective action tactics

In this paper, we examine the role of out-group signals and in-group leader tactics in the choice and evaluation of rival in-group leader candidates. Study 1 found preference for a negotiating in-group leader over an oppositional leader, mediated by perceived leader effectiveness and prototypicality. In Study 2, participants chose a leader who had received out-group endorsement, and in Studies 3 and 4, participants chose a negotiating in-group leader where the out-group was prepared to negotiate and an oppositional leader where the out-group was not prepared to negotiate. In the latter three studies, there was evidence for participants being strategic in their choices: effects were mediated by effectiveness but not prototypicality. These findings suggest our understanding of collective action will be enriched through attention to the situational cues provided by out-groups, and to the context of competing voices of collective action leadership

Executive difficulties in Developmental Coordination Disorder: Methodological issues and future directions

Motor skills and cognition have often been studied separately, but there is increasing understanding of the close relationship between these abilities over development. Motor coordination difficulties are central to the diagnosis of Developmental Coordination Disorder (DCD), and recent evidence suggests that certain cognitive processes, known as ‘executive functions’, may be affected in individuals with this neurodevelopmental disorder. In this article, we review the research concerning executive functions in DCD, considering behavioural, neuroimaging and questionnaire studies of a range of processes. We highlight methodological issues relating to our current understanding of executive functioning difficulties in DCD, including problems with interpretation of results based on the tasks used. We suggest future directions for research in this area, including the relationship of laboratory research to interventions within ‘real-world’ contexts

Mitochondrial damage-associated molecular patterns (DAMPs) in inflammatory bowel disease

Background The inflammatory bowel diseases (IBD) ulcerative colitis (UC) and Crohn’s disease (CD) are chronic relapsing inflammatory disorders which have a rising incidence and cause significant morbidity. There are currently several treatment options with many more in the drug pipeline, but there are a lack of accurate biomarkers for decisions on treatment choice, assessment of disease activity and prognostication. There is a growing interest and desire for personalised or ‘precision’ medicine in IBD where novel biomarkers may help individualise IBD care in terms of diagnosis, choice of therapy, monitoring of response and detection of relapse. One class of functionally active biomarkers which have yet to be thoroughly investigated in IBD is damage-associated molecular patterns (DAMPs) including mitochondrial DNA (mtDNA). It has been recently shown that gut mitochondrial dysfunction can result in loss of epithelial barrier function and the development of colitis. Mitochondrial DAMPs have recently been described as elevated in several inflammatory diseases. Hypothesis The primary hypothesis of this thesis is that circulating levels of mtDNA is elevated in IBD. Secondary hypotheses are: (a) levels of other mitochondrial DAMPs are elevated in IBD, (b) circulating mtDNA can be used as a novel biomarker in IBD and (c) mtDNA is released locally at sites of inflammation in IBD. Methods Plasma and serum were collected prospectively from recruited IBD patients and non-IBD controls. Faeces and colonic tissue were collected from a subset of these patients. mtDNA in serum, plasma and faeces was measured using qPCR (amplifying COXIII/ND2 genes). Mass spectrometry was used to detect mitochondrial formylated peptides in the plasma of a subset of patients. IBD tissue was assessed for (a) mitochondrial damage using transmission electron microscopy (TEM) and (b) TLR9 expression, the target for mtDNA. Results 97 patients with IBD (67 UC and 30 CD), and 40 non-IBD controls were recruited. Plasma mtDNA levels were increased in UC and CD (both p<0.0001) compared to non-IBD controls; with significant correlations with blood (CRP, albumin, white cell count), clinical and endoscopic markers of severity; and disease activity. In active UC, we detected significantly higher circulating mitochondrial formylated peptides and faecal mtDNA levels (vs. non-IBD controls [p<0.01 and <0.0001 respectively]) with demonstrable TEM evidence of intestinal mucosal mitochondrial damage. In active IBD, TLR9+ lamina propria inflammatory cells were significantly higher in UC/CD compared to controls (both p<0.05). Conclusions Taken together, the findings suggest mtDNA is released during active inflammation in inflammatory bowel disease and is a potential novel mechanistic biomarker