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International audience; Advances in single-cell RNA sequencing have allowed for the identification of cellular subtypes on the basis of quantification of the number of transcripts in each cell. However, cells might also differ in the spatial distribution of molecules, including RNAs. Here, we present DypFISH, an approach to quantitatively investigate the subcellular localization of RNA and protein. We introduce a range of analytical techniques to interrogate single-molecule RNA fluorescence in situ hybridization (smFISH) data in combination with protein immunolabeling. DypFISH is suited to study patterns of clustering of molecules, the association of mRNA-protein subcellular localization with microtubule organizing center orientation, and interdependence of mRNA-protein spatial distributions. We showcase how our analytical tools can achieve biological insights by utilizing cell micropatterning to constrain cellular architecture, which leads to reduction in subcellular mRNA distribution variation, allowing for the characterization of their localization patterns. Furthermore, we show that our method can be applied to physiological systems such as skeletal muscle fibers.

International audience; Phylogenetic relationships within the Orchideae sensu Pridgeon et al, remain one of the biggest unresolved issues in our understanding of the taxonomy of the orchids. Members of the Orchideae are numerous and widespread in Africa but remain poorly represented in phylogenetic research. In this study we included a broad sampling of African taxa for which we sequenced three plastid (rbcl, matK and trnL + trnL-F) and two nuclear regions (ITS and 18S). We used 368 sequences representing 278 species and 49 genera to infer relationships using the Bayesian Inference and Maximum Likelihood method. Our results show strong support for three clades, two of which almost entirely match the historical circumscription of Orchidinae and Habenariinae, and the third, Bartholininae, sister to the former two, includes the genera Holothrix and Bartholina. Stenoglottis should be assigned to Orchidinae and not to Habenariinae. Several genera such as Habenaria, Cynorkis and Benthamia are shown to be para- or polyphyletic: Bonatea, Centrostigma, Platycoryne and Roeperocharis are all embedded in Habenaria; Physoceras, Arnottia and part of Benthamia are embedded in Cynorkis. We propose a subdivision of Orchideae sensu lato into nine subtribes, but refrain from making generic re-arrangements until more extensive or more in-depth studies have been done.

14 pages; International audience; Savanna is a species-rich biome, that includes many modern mammal lineages and C4 grass (Poaceae) species. The greater productivity and grazing pressure associated with savannas is likely attributable to the foliar traits of the grasses they support. Thus, it is important to understand the complex relationships between the abiotic environment, foliar attributes and the floristic composition of savanna grasses, and the supported grazer densities. We sampled 37 grass communities in the Kruger National Park (South Africa) across three soil types and along a rainfall gradient and found that these communities lack strong phylogenetic structure. We then measured specific leaf area and leaf tensile strength for 384 individuals representing 66 species and found that both traits were strongly phylogenetically structured and associated with both rainfall and soil type. Finally, we found that grazer densities in the Park are correlated with the foliar traits of the associated grass communities, but the resolution of our data do not allow for a thorough analysis of this association. Our results demonstrate the complex interactions between climate, soils and grazer densities relative to C4 grass functional traits.

[EN] Continuous low-level supply or in situ generation of hydrogen peroxide (H2O2) is essential for the stability of unspecific peroxygenases, which are deemed ideal biocatalysts for the selective activation of C-H bonds. To envisage potential large scale applications of combined catalytic systems the reactions need to be simple, efficient and produce minimal by-products. We show that gold-palladium nanoparticles supported on TiO2 or carbon have sufficient activity at ambient temperature and pressure to generate H2O2 from H2 and O2 and supply the oxidant to the engineered unspecific heme-thiolate peroxygenase PaDa-I. This tandem catalyst combination facilitates efficient oxidation of a range of C-H bonds to hydroxylated products in one reaction vessel with only water as a by-product under conditions that could be easily scaled., S.J.F., R.J.L. and G.J.H. gratefully acknowledge Cardiff University for financial support as part of the MAXNET Energy Consortium, in addition SJF acknowledges the award of a Prize Research Fellowship from the University of Bath and a RSC Research Mobility Grant (RM1802-7768). Dr. Robert Mart (Cardiff University) is thanked for preforming the chiral analysis. M.A. thanks funding from Spanish project Lignolution- BIO2016-79106-R. Financial support by the University of the Free State (post-doctoral fellowship JvM), the Claude Leon Foundation (post-doctoral fellowship SK) and the South African Department of Science and Technology/National Research Foundation Centre of Excellence in Catalysis (C*Change) is also gratefully acknowledged.

de congrès publié : De Jager EJ, Van Schoor AN, Hoffman JW, Oettle AC, Fonta C, Beaudet A. 2018 Sulcal pattern variation in extant human brain endocasts. American Association for Physical Anthropologists. Austin, April 10-14. American Journal of Physical Anthropology, 165, suppl 63 (poster).

SXP 1062 is a Be X-ray binary (BeXB) located in the Small Magellanic Cloud. It hosts a longperiodX- ray pulsar and is likely associated with the supernova remnant MCSNRJ0127-7332. In this work we present a multiwavelength view on SXP 1062 in different luminosity regimes. We consider monitoring campaigns in optical (OGLE survey) and X-ray (Swift telescope). During these campaigns a tight coincidence of X-ray and optical outbursts is observed. We interpret this as typical Type I outbursts as often detected in BeXBs at periastron passage of the neutron star (NS). To study different X-ray luminosity regimes in depth, during the source quiescence we observed it with XMM-Newton while Chandra observations followed an X-ray outburst. Nearly simultaneously with Chandra observations in X-rays, in optical the RSS/SALT telescope obtained spectra of SXP 1062. On the basis of our multiwavelength campaign we propose a simple scenario where the disc of the Be star is observed face-on, while the orbit of the NS is inclined with respect to the disc. According to the model of quasi-spherical settling accretion our estimation of the magnetic field of the pulsar in SXP 1062 does not require an extremely strong magnetic field at the present time.© 2018 The Author(s)., AGG and LMO are supported by the Deutsches Zentrum fur Luft und Raumfahrt (DLR) grants FKZ 50 OR 1404 and FKZ 50 OR 1508. LMO acknowledging partial support by the Russian Government Program of Competitive Growth of Kazan Federal University. MK acknowledges funding by the Bundesministerium fur Wirtschaft und Technologie under Deutsches Zentrum fur Luft- und Raumfahrt grants 50 OR 1113 and 50 OR 1207. SBP is supported by the Russian Science Foundation grant 14-12-00146. MPES received funding through the Claude Leon Foundation Postdoctoral Fellowship program and the National Research Foundation.

21 págs., fig. -- http://creativecommons.org/licenses/by/4.0/, New theoretical approaches developed in the last years predict that macroscopic quantum gravity effects in black holes should lead to modifications of the gravitational wave signals expected in the framework of classical general relativity, with these modifications being characterized in certain scenarios by the existence of dampened rep-etitions of the primary signal. Here we use the fact that non-perturbative corrections to the near-horizon external geometry of black holes are necessary for these modifications to exist, in order to classify different proposals and paradigms with respect to this criterion and study in a neat and systematic way their phenomenology. Proposals that lead naturally to the existence of echoes in the late-time ringdown of gravitational wave signals from black hole mergers must share the replacement of black holes by horizonless configurations with a physical surface showing reflective properties in the relevant range of frequencies. On the other hand, proposals or paradigms that restrict quantum gravity effects on the external geometry to be perturbative, such as black hole complementarity or the closely related firewall proposal, do not display echoes. For the sake of completeness we exploit the interplay between the timescales associated with the formation of firewalls and the mechanism behind the existence of echoes in order to conclude that even unconventional distortions of the firewall concept (such as naked firewalls) do not lead to this phenomenon., Financial support was provided by the Spanish MINECO through the projects FIS2011- 30145-C03-01, FIS2011-30145-C03-02, FIS2014-54800-C2-1, FIS2014-54800-C2-2 (with FEDER contribution), and by the Junta de Andalucía through the project FQM219. RCR is funded by a postdoctoral fellowship from the Claude Leon Foundation of South Africa.

The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic., This work was supported by the Deutscher Akademischer Austauschdienst (DAAD to Philipps Universität Marburg and Zhejiang University, Hangzhou), the Chinesisch Deutsches Zentrum für Wissenschaftsförderung (“CDZ” to Z.G. and W.J.P.), and the Chinese Academy of Science (CAS). Part of this work was supported by the National Natural Science Foundation (51390481, 81227902, 81625011), National Basic Research Program (2014CB931900) of China (to Y.S.), by the European Commission grant Futurenanoneeds (to V.P. and W.J.P.), by the Spanish Ministerio de Economia y Competitividad (CTQ2011-23167 and CTQ2014-59808R to R.A.A.P.), the Generalitat of Catalunya (2014-SGR-612 to R.A.A.P.), the Deutsche Forschungsgemeinschaft (DFG) (AL552/8-1 to R.T.), the Swiss National Science Foundation (NRP62 to P.H.), the Claude & Julianna Foundation (grant to P.H.), the National Science Foundation (NSF) grants CHE-1306928 (to R.P.) and ECS-0601345; CBET 0933384; CBET 0932823; and CBET 1036672 (to N.A.K.), Canadian Institute of Health Research (grant to W.C.W.C.), and Natural Sciences and Engineering Research Council of Canada (grant to W.C.W.C.). S.A. and B.P. acknowledge a fellowship from the Alexander von Humboldt Foundation. N.F. acknowledges the Lars Hiertas Minne Foundation. M.C. acknowledges Ikerbasque for a Research Fellow position. X.C. acknowledges the Intramural Research Program (IRP), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH). B.Z.T. acknowledges the Innovation and Technology Commission of Hong Kong (ITC-CNERC14SC01). The Pancreatic Cancer research of A.E.N. and H.M. was funded by the U.S. National Cancer Institute, NIH grant # U01CA198846. A.E. acknowledges Junta de Andalucía (Spain) for a Talentia Postdoc Fellowship, co-financed by the European Union's Seventh Framework Programme, grant agreement no 267226. A.G.S. acknowledges support by BOF (UGent) and FWO (Research Foundation Flanders). Part of this work was supported by the National Natural Science Foundation of China.

15 pags., app., Quantization of the gravitational field may allow the existence of a decay channel of black holes into white holes with an explicit time-reversal symmetry. The definition of a meaningful decay probability for this channel is studied in spherically symmetric situations. As a first nontrivial calculation, we present the functional integration over a set of geometries using a single-variable function to interpolate between black-hole and white-hole geometries in a bounded region of spacetime. This computation gives a finite result which depends only on the Schwarzschild mass and a parameter measuring the width of the interpolating region. The associated probability distribution displays an exponential decay law on the latter parameter, with a mean lifetime inversely proportional to the Schwarzschild mass. In physical terms this would imply that matter collapsing to a black hole from a finite radius bounces back elastically and instantaneously, with negligible time delay as measured by external observers. These results invite to reconsider the ultimate nature of astrophysical black holes, providing a possible mechanism for the formation of black stars instead of proper general relativistic black holes. The existence of both this decay channel and black stars can be tested in future observations of gravitational waves., Financial support was provided by the Spanish MINECO through the projects FIS2011-30145-C03-01, FIS2011-30145-C03-02, FIS2014-54800-C2-1, FIS2014-54800-C2-2 (with FEDER contribution), and by the Junta de Andalucía through the project FQM219. R.C-R. acknowledges support, at different stages of the elaboration of this work, from the Math Institute of the University of Granada (IEMath-GR), the research project MINECO-FEDER MTM2013-47828-C2-1-P, and the Claude Leon Foundation.

34 pags., 2 apps., In this paper we revisit the motivation and construction of a unified theory of gravity and electromagnetism, following Weyl's insights regarding the appealing potential connection between the gauge invariance of electromagnetism and the conformal invariance of the gravitational field. We highlight that changing the local symmetry group of spacetime permits to construct a theory in which these two symmetries are combined into a putative gauge symmetry but with second-order field equations and non-trivial mass scales, unlike the original higher-order construction by Weyl. We prove that the gravitational field equations are equivalent to the (trace-free) Einstein field equations, ensuring their compatibility with known tests of general relativity. As a corollary, the effective cosmological constant is rendered radiatively stable due to Weyl invariance. A novel phenomenological consequence characteristic of this construction, potentially relevant for cosmological observations, is the existence of an energy scale below which effects associated with the non-integrability of spacetime distances, and an effective mass for the electromagnetic field, appear simultaneously (as dual manifestations of the use of Weyl connections). We explain how former criticisms against Weyl's ideas lose most of their power in its present reincarnation, which we refer to as Weyl relativity, as it represents a Weyl-invariant, unified description of both the Einstein and Maxwell field equations., Financial support was provided by the Spanish MINECO through the projects FIS2011-30145-C03-01, FIS2011-30145-C03-02, FIS2014-54800-C2-1, FIS2014-54800-C2-2 (with FEDER contribution), and by the Junta de Andalucıa through the project FQM219. R.C-R. acknowledges support, at different stages of the elaboration of this work, from the Math Institute of the University of Granada (IEMath-GR), the research project MINECO-FEDER MTM2013-47828-C2-1-P, and the Claude Leon Foundation

International audience; Strain R1333, isolated from commercially available smoked salmon, was identified as Lactobacillus sakei based on biochemical tests, sugar fermentation reactions (API 50 CHL), PCR with species-specific primers and sequencing of the 16S rRNA gene. Strain R1333 produces a 3811 kDa class Ila bacteriocin, active against Streptococcus caprinus, Streptococcus macedonicus, Streptococcus spp., L sakei, Lactococcus lactis subsp. lactis. Listeria innocua, Listeria ivanovii subsp. ivanovii and Listeria monocytogenes. The mode of activity against L innocua 2030C and L ivanovii subsp. ivanovii ATCC 19119 was bactericidal, resulting in cell lysis and enzyme- and DNA-leakage. The highest level of activity (1600 AU/mL) was recorded when cells were grown at 30 degrees C in MRS broth (initial pH 6.5). Only 800 AU/mL was recorded when strain R1333 was grown in MRS without Tween 80. Lower levels of bacteriocin production were recorded when strain R1333 was grown in MRS at 20 degrees C. Peptide R1333 adsorbs at low levels (200 AU/mL) to producer cells. Purification of bacteriocin R1333 was performed by 60% ammonium sulfate precipitation, followed by separation on a SepPak C(18) column and reverse-phase HPLC on a Nucleosil C18 column with a linear gradient from 0.1% TFA to 90% acetonitryl. A molecular mass of 3811 kDa was determined by mass spectrometry. Based on mass spectrometry and sequencing of the PCR amplified fragment targeting the sakG gene, L sakei R1333 is a potential producer of sakacin G. This is the first report of the identification of sakacin G produced by L. sakei isolated from smoked salmon. (C) 2010 Elsevier Ltd. All rights reserved.

The principles of quantum field theory in flat spacetime suggest that gravity is mediated by a massless particle with helicity ±2, the so-called graviton. It is regarded as textbook knowledge that, when the self-coupling of a particle with these properties is considered, the long-wavelength structure of such a nonlinear theory is fixed to be that of general relativity. However, here we indicate that these arguments conceal an implicit assumption which is surreptitiously motivated by the very knowledge of general relativity. This is shown by providing a counterexample: we revisit a nonlinear theory of gravity which is not structurally equivalent to general relativity and that, in the non-interacting limit, describes a free helicity ±2 graviton. We explicitly prove that this theory, known as Weyl-transverse gravity (unimodular gravity with explicit Weyl invariance), can be understood as the result of self-coupling in complete parallelism to the well-known case of general relativity. We discuss the absence of cosmological constant problem in this theory, highlighting that it provides a particular realization of previous arguments formulated in studies of the emergence of the gravitational interaction from condensed-matter-like models. Overall, we conclude that the consideration that gravity is mediated by a massless particle with helicity ±2 does not inextricably lead to the cosmological constant problem.© 2018 Elsevier Inc., Financial support was provided by the Spanish MICINN, Spain through Project Nos. FIS2014-54800-C2-1, FIS2017-86497-C2-1, FIS2014-54800-C2-2 and FIS2017-86497-C2-2 (with FEDER contribution), and by the Junta de Andalucia, Spain through Project No. FQM219. R.C.R. acknowledges support from CSIC through the JAE-predoc program, cofunded by FSE, Spain, and the Claude Leon Foundation in South Africa.