Transgenerational effects in asexually reproduced offspring of Populus

The response of trees to a changing climate can be affected by transgenerational phenotypic plasticity, i.e. phenotypic variation that is conserved and transferred to the offspring. Transgenerational plasticity that is influenced by epigenetics (heritable changes in gene function that do not result from changes in DNA sequence) during both sexual and asexual reproduction are of major relevance for adaptation of plants to climate change. To understand the transgenerational effects on the responses of vegetatively propagated poplar (Populus deltoides and P. trichocarpa) ramets (cuttings) to a changing environment, we tested whether the temperature and photoperiod experienced by the mother trees (genets) persistently affects the phenology of the cuttings grown in a common environment. We weekly monitored the bud phenology of the cuttings collected from the parent trees that have been growing across Europe along a >2100 km latitudinal gradient for at least 18 years. In addition, we asked whether there was variation in DNA methylation as measured by Methylation Sensitive Amplified Fragment Length Polymorphism (MSAPs) in the clones due to the different environmental conditions experienced by the parent trees. Our results indicate a transgenerational effect on bud phenology in the asexually reproduced offspring (vegetative cuttings). The temperatures experienced by the parent tree clones (from different geographic regions) altered the bud flush of the cuttings in the common garden. However, no significant epigenetic variation was detected in the cuttings of the parent trees within single genotypes growing under different climates. In sum, our results show that trees have the potential to respond to rapid climate change but the mechanism behind these changes needs to be further investigated by more powerful molecular methods like whole-genome bisulphite sequencing techniques

Theory of small aspect ratio waves in deep water

In the limit of small values of the aspect ratio parameter (or wave steepness) which measures the amplitude of a surface wave in units of its wave-length, a model equation is derived from the Euler system in infinite depth (deep water) without potential flow assumption. The resulting equation is shown to sustain periodic waves which on the one side tend to the proper linear limit at small amplitudes, on the other side possess a threshold amplitude where wave crest peaking is achieved. An explicit expression of the crest angle at wave breaking is found in terms of the wave velocity. By numerical simulations, stable soliton-like solutions (experiencing elastic interactions) propagate in a given velocities range on the edge of which they tend to the peakon solution.Comment: LaTex file, 16 pages, 4 figure

Comparative profiling of metastatic 4T1- vs. non-metastatic Py230-based mammary tumors in an intraductal model for triple-negative breast cancer

The transition of ductal carcinoma in situ (DCIS) to invasive carcinoma (IC) in breast cancer can be faithfully reproduced by the intraductal mouse model. Envisaging to use this model for therapeutic testing, we aimed to in-depth characterize the tumor immunity associated with the differential progression of two types of intraductal tumors. More specifically, we focused on triple-negative breast cancer (TNBC) and intraductally inoculated luciferase-expressing metastatic 4T1 and locally invasive Py230 cells in lactating mammary glands of syngeneic BALB/c and C57BL/6 female mice, respectively. Although the aggressive 4T1 cells rapidly formed solid tumors, Py230 tumors eventually grew to a similar size through enhanced proliferation. Yet, ductal tumor cell breakthrough and metastasis occurred earlier in the 4T1- compared to the Py230-based intraductal model and was associated with high expression of matrix metalloproteinase (MMP)-9, vascular endothelial growth factor (VEGF), chitinase 3-like 1 (CHI3L1) and lipocalin 2 (LCN2) as well as an increased influx of immune cells (mainly macrophages, neutrophils and T-cells). Moreover, activated cytotoxic T-cells, B-cells and programmed death-1 (PD-1)-positive cells were more prominent in the 4T1-based intraductal model in line with enhanced pro-inflammatory cytokine and gene expression profiles. Py230-based tumors showed a more immunosuppressed anti-inflammatory profile with a high amount of regulatory T-cells, which may account for the decreased T-cell activation but increased proliferation compared to the 4T1-based tumors. Taken together, our results highlight the differential immunological aspects of aggressive metastatic and non-aggressive intraductal progression of 4T1- vs. Py230-based tumors, providing a base for future studies to explore therapy using these intraductal TNBC models

OMO-1 reduces progression and enhances cisplatin efficacy in a 4T1-based non-c-MET addicted intraductal mouse model for triple-negative breast cancer

c-MET is considered a driver of cancer progression, impacting tumor growth and tumor-supporting stroma. Here, we investigated the therapeutic efficacy of OMO-1, a potent and selective c-MET inhibitor, in an immunocompetent intraductal mouse model for triple-negative breast cancer (TNBC). OMO-1 reduced non-c-MET addicted 4T1 tumor progression dose dependently as monotherapeutic and provided additional disease reduction in combination with cisplatin. At the stromal level, OMO-1 significantly reduced neutrophil infiltration in 4T1 tumors, promoted immune activation, and enhanced cisplatin-mediated reduction of tumor-associated macrophages. OMO-1 treatment also reduced 4T1 tumor hypoxia and increased expression of pericyte markers, indicative for vascular maturation. Corroborating this finding, cisplatin delivery to the 4T1 primary tumor was enhanced upon OMO-1 treatment, increasing cisplatin DNA-adduct levels and tumor cell death. Although verification in additional cell lines is warranted, our findings provide initial evidence that TNBC patients may benefit from OMO-1 treatment, even in cases of non-c-MET addicted tumors

This is funny: on the beneficial role of self-enhancing and affiliative humour in job design

Building on positive psychology, the present study aims to address the role of humour in the workplace, and particularly in job design, one of the crucial job aspects contributing to employee well-being. Specifically, we examine the main effects of self-enhancing and affiliative types of humour both on burnout and work engagement. Furthermore, we study whether these humour styles serve as personal resources, moderating the associations of job hindrances (i.e., role conflict), job challenges (i.e., workload) and job resources (i.e., social support) with burnout and work engagement, as outlined in the Job Demands-Resources model. Results in a large sample of Belgian employees (N= 1200) showed that both types of humour related negatively to burnout and positively to work engagement. No interactions between humour and the job characteristics were found in the prediction of burnout. The significant interactions in predicting work engagement showed that self-enhancing and affiliative humour played a positive role, particularly when role conflict and social support were low. No interactions with workload were found. The discussion aims to shed light on the unexpected results and to further the study of the humour-health hypothesis.¡Tiene gracia!: sobre el rol beneficioso del humor como afrontamiento y afiliativo en el diseño del trabajo. El presente estudio tiene como objetivo abordar el papel del humor en el ámbito laboral, en particular en el diseño del trabajo. En concreto, se examinan los efectos directos del humor afiliativo y el humor como afrontamiento en el burnout y el engagement. Además, basándonos en el modelo de Demandas-Recursos Laborales, analizamos si estos estilos de humor pueden actuar como recursos personales. En concreto, se examina su papel moderador en la relación entre estresores que suponen un obstáculo (i.e., conflicto de rol) o un reto (i.e., carga laboral), recursos laborales (i.e., apoyo social) y el burnout y el engagement. Los resultados en una amplia muestra de trabajadores belgas (N= 1.200) muestran que ambos tipos de humor se relacionan negativamente con el burnout y positivamente con el engagement. No se hallaron interacciones entre el humor y las características laborales a la hora de predecir el burnout. Sin embargo, las interacciones encontradas con vigor indican que ambos tipos de humor juegan un papel positivo, especialmente con bajos niveles de conflicto de rol y apoyo social. La discusión trata de explicar algunos hallazgos inesperados, así como promover el estudio de la hipótesis humor-salud

First measurement of the Hubble Constant from a Dark Standard Siren using the Dark Energy Survey Galaxies and the LIGO/Virgo Binary–Black-hole Merger GW170814

International audienceWe present a multi-messenger measurement of the Hubble constant H 0 using the binary–black-hole merger GW170814 as a standard siren, combined with a photometric redshift catalog from the Dark Energy Survey (DES). The luminosity distance is obtained from the gravitational wave signal detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO)/Virgo Collaboration (LVC) on 2017 August 14, and the redshift information is provided by the DES Year 3 data. Black hole mergers such as GW170814 are expected to lack bright electromagnetic emission to uniquely identify their host galaxies and build an object-by-object Hubble diagram. However, they are suitable for a statistical measurement, provided that a galaxy catalog of adequate depth and redshift completion is available. Here we present the first Hubble parameter measurement using a black hole merger. Our analysis results in , which is consistent with both SN Ia and cosmic microwave background measurements of the Hubble constant. The quoted 68% credible region comprises 60% of the uniform prior range [20, 140] km s−1 Mpc−1, and it depends on the assumed prior range. If we take a broader prior of [10, 220] km s−1 Mpc−1, we find (57% of the prior range). Although a weak constraint on the Hubble constant from a single event is expected using the dark siren method, a multifold increase in the LVC event rate is anticipated in the coming years and combinations of many sirens will lead to improved constraints on H 0

GW170104: Observation of a 50-Solar-Mass Binary Black Hole Coalescence at Redshift 0.2

We describe the observation of GW170104, a gravitational-wave signal produced by the coalescence of a pair of stellar-mass black holes. The signal was measured on January 4, 2017 at 10: 11: 58.6 UTC by the twin advanced detectors of the Laser Interferometer Gravitational-Wave Observatory during their second observing run, with a network signal-to-noise ratio of 13 and a false alarm rate less than 1 in 70 000 years. The inferred component black hole masses are 31.2(-6.0)(+8.4)M-circle dot and 19.4(-5.9)(+5.3)M(circle dot) (at the 90% credible level). The black hole spins are best constrained through measurement of the effective inspiral spin parameter, a mass-weighted combination of the spin components perpendicular to the orbital plane, chi(eff) = -0.12(-0.30)(+0.21) . This result implies that spin configurations with both component spins positively aligned with the orbital angular momentum are disfavored. The source luminosity distance is 880(-390)(+450) Mpc corresponding to a redshift of z = 0.18(-0.07)(+0.08) . We constrain the magnitude of modifications to the gravitational-wave dispersion relation and perform null tests of general relativity. Assuming that gravitons are dispersed in vacuum like massive particles, we bound the graviton mass to m(g) <= 7.7 x 10(-23) eV/c(2). In all cases, we find that GW170104 is consistent with general relativity

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Localization and Broadband Follow-Up of the Gravitational-Wave Transient GW150914

A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser InterferometerGravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimatesof the time, significance, and sky location of the event were shared with 63 teams of observers covering radio,optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter wedescribe the low-latency analysis of the GW data and present the sky localization of the first observed compactbinary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-rayCoordinates Network circulars, giving an overview of the participating facilities, the GW sky localizationcoverage, the timeline, and depth of the observations. As this event turned out to be a binary black hole merger,there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadbandcampaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broadcapabilities of the transient astronomy community and the observing strategies that have been developed to pursueneutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-upcampaign are being disseminated in papers by the individual teams

Does job insecurity threaten who you are? Introducing a social identity perspective to explain well-being and performance consequences of job insecurity

This paper introduces a social identity perspective to job insecurity research. Worrying about becoming jobless, we argue, is detrimental because it implies an anticipated membership of a negatively evaluated group – the group of unemployed people. Job insecurity hence threatens a person’s social identity as an employed person. This in turn will affect well-being and job performance. A three-wave survey study among 377 British employees supports this perspective. Persons who felt higher levels of job insecurity were more likely to report a weaker social identity as an employed person. This effect was found to be stable over time, and also held against a test of reverse causality. Furthermore, social identity as an employed person influenced well-being and in-role job performance and mediated the effect of job insecurity on these two variables over time. Different to the expectations, social identity as an employed person and organisational proactivity were not connected. The findings deliver interesting evidence for the role of social identity as an employed person in the relationships between job insecurity and its consequences. Theoretically, this perspective illustrates the individual and group-related nature of job insecurity and offers a novel way of connecting work situations with individual well-being, behaviour, and attitudes