17,225 research outputs found

    Low-mass bursty galaxies in JADES efficiently produce ionising photons and could represent the main drivers of reionisation

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    © 2023 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/We study galaxies in JADES Deep to study the evolution of the ionising photon production efficiency, Οion\xi_{\rm{ion}}, observed to increase with redshift. We estimate Οion\xi_{\rm{ion}} for a sample of 677 galaxies at z∌4−9z \sim 4 - 9 using NIRCam photometry. Specifically, combinations of the medium and wide bands F335M-F356W and F410M-F444W to constrain emission lines that trace Οion\xi_{\rm{ion}}: Hα\alpha and [OIII]. Additionally, we use the spectral energy distribution fitting code \texttt{Prospector} to fit all available photometry and infer galaxy properties. The flux measurements obtained via photometry are consistent with FRESCO and NIRSpec-derived fluxes. Moreover, the emission-line-inferred measurements are in tight agreement with the \texttt{Prospector} estimates. We also confirm the observed Οion\xi_{\rm{ion}} trend with redshift and MUV_{\rm{UV}}, and find: logâĄÎŸion(z,MUV)=(0.05±0.02)z+(0.11±0.02)MUV+(27.33±0.37)\log \xi_{\rm{ion}} (z,\text{M}_{\rm{UV}}) = (0.05 \pm 0.02)z + (0.11 \pm 0.02) \text{M}_{\rm{UV}} + (27.33 \pm 0.37). We use \texttt{Prospector} to investigate correlations of Οion\xi_{\rm{ion}} with other galaxy properties. We see a clear correlation between Οion\xi_{\rm{ion}} and burstiness in the star formation history of galaxies, given by the ratio of recent to older star formation, where burstiness is more prevalent at lower stellar masses. We also convolve our Οion\xi_{\rm{ion}} relations with luminosity functions from the literature, and constant escape fractions of 10 and 20\%, to place constraints on the cosmic ionising photon budget. By combining our results, we find that if our sample is representative of the faint low-mass galaxy population, galaxies with bursty star formation are efficient enough in producing ionising photons and could be responsible for the reionisation of the Universe.Peer reviewe

    Population dynamics of rhizosphere microflora of mycorrhizal and non-mycorrhizal barley (Hordeum vulgare) in organic amended soils

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    A pot experiment was conducted to study the response of barley (Hordeum vulgare) to inoculation with Glomus fasciculatum in unsterilised organic matter amended soils on the colonization of barley roots by (V)-Arbuscular mycorrhizal (AM) fungi and other rhizosphere microflora. The populations of bacteria, fungi and actinomycetes were higher in amended than in control soils. Paddy straw compost (PSC) stimulated all three groups of organisms (bacteria, fungi and actinomycetes) more than city compost (CC). The fungal and actinomycetes populations decreased with increasing plant age. The effect was more pronounced in the rhizosphere of paddy straw-amended soils. The mycorrhizal spore count and the colonization of barley roots by (V)-AM were more pronounced in soils amended with PSC than in those amended with CC

    Comprehensive Fragment Screening of the SARS‐CoV‐2 Proteome Explores Novel Chemical Space for Drug Development

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    SARS‐CoV‐2 (SCoV2) and its variants of concern pose serious challenges to the public health. The variants increased challenges to vaccines, thus necessitating for development of new intervention strategies including anti‐virals. Within the international Covid19‐NMR consortium, we have identified binders targeting the RNA genome of SCoV2. We established protocols for the production and NMR characterization of more than 80 % of all SCoV2 proteins. Here, we performed an NMR screening using a fragment library for binding to 25 SCoV2 proteins and identified hits also against previously unexplored SCoV2 proteins. Computational mapping was used to predict binding sites and identify functional moieties (chemotypes) of the ligands occupying these pockets. Striking consensus was observed between NMR‐detected binding sites of the main protease and the computational procedure. Our investigation provides novel structural and chemical space for structure‐based drug design against the SCoV2 proteome

    “Real impact”: challenges and opportunities in bridging the gap between research and practice – making a difference in industry, policy, and society

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    Achieving impact from academic research is a challenging, complex, multifaceted, and interconnected topic with a number of competing priorities and key performance indicators driving the extent and reach of meaningful and measurable benefits from research. Academic researchers are incentivised to publish their research in high-ranking journals and academic conferences but also to demonstrate the impact of their outputs through metrics such as citation counts, altmetrics, policy and practice impacts, and demonstrable institutional decision-making influence. However, academic research has been criticized for: its theoretical emphasis, high degree of complexity, jargon-heavy language, disconnect from industry and societal needs, overly complex and lengthy publishing timeframe, and misalignment between academic and industry objectives. Initiatives such as collaborative research projects and technology transfer offices have attempted to deliver meaningful impact, but significant barriers remain in the identification and evaluation of tangible impact from academic research. This editorial focusses on these aspects to deliver a multi-expert perspective on impact by developing an agenda to deliver more meaningful and demonstrable change to how “impact” can be conceptualized and measured to better align with the aims of academia, industry, and wider society. We present the 4D model - Design, Deliver, Disseminate, and Demonstrate - to provide a structured approach for academia to better align research endeavors with practice and deliver meaningful, tangible benefits to stakeholders.</p

    Celebrating Professor Rajeev K. Varshney's transformative research odyssey from genomics to the field on his induction as Fellow of the Royal Society

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    Professor Rajeev K. Varshney's transformative impact on crop genomics, genetics, and agriculture is the result of his passion, dedication, and unyielding commitment to harnessing the potential of genomics to address the most pressing challenges faced by the global agricultural community. Starting from a small town in India and reaching the global stage, Professor Varshney's academic and professional trajectory has inspired many scientists active in research today. His ground-breaking work, especially his effort to list orphan tropical crops to genomic resource-rich entities, has been transformative. Beyond his scientific achievements, Professor Varshney is recognized by his colleagues as an exemplary mentor, fostering the growth of future researchers, building institutional capacity, and strengthening scientific capability. His focus on translational genomics and strengthening seed system in developing countries for the improvement of agriculture has made a tangible impact on farmers' lives. His skills have been best utilized in roles at leading research centres where he has applied his expertise to deliver a new vision for crop improvement. These efforts have now been recognized by the Royal Society with the award of the Fellowship (FRS). As we mark this significant milestone in his career, we not only celebrate Professor Varshney's accomplishments but also his wider contributions that continue to transform the agricultural landscape

    Psychological distress and workplace risk inequalities among conservation professionals

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    Workplaces can be sources of both stress and support, affecting employees’ mental health and productivity. Yet, little research has investigated variability in workplace risk factors for poor mental health in conservation. We aimed to explore how patterns of psychological distress – a state of emotional disturbance – and associated workplace risk factors vary between conservation job roles. Working with three case study organisations in India, South Africa, and Cambodia, we surveyed 280 field-based, office-based, and research staff. Moderate or severe psychological distress was reported by 28.9%. Field-based practitioners reported a greater imbalance between workplace efforts and rewards (0.35 standard deviation (SD), 95% credibility interval (CI) 0.03 - 0.67) than their colleagues, which was associated with greater psychological distress (0.24 SD, 95% CI 0.10 - 0.39). After controlling for this mediated relationship, researchers reported greater psychological distress than field-based practitioners (0.37 SD, 95% CI 0.02 - 0.72). However, when accounting for all direct and indirect effects, there was no overall difference in distress between roles. Employers, funders, professional societies, and other institutions seeking to support conservationists’ mental health should understand and offer support tailored to role-specific challenges. Doing so might enhance conservationists’ wellbeing while strengthening their ability to reverse global nature loss

    Search for diphoton resonances in the mass range from 150 to 850 GeV in pp collisions at root s=8 TeV

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    Results are presented of a search for heavy particles decaying into two photons. The analysis is based on a 19.7 fb(-1) sample of proton-proton collisions at root s = 8 TeV collected with the CMS detector at the CERN LHC. The diphoton mass spectrum from 150 to 850 GeV is used to search for an excess of events over the background. The search is extended to new resonances with natural widths of up to 10% of the mass value. No evidence for new particle production is observed and limits at 95% confidence level on the production cross section times branching fraction to diphotons are determined. These limits are interpreted in terms of two-Higgs-doublet model parameters. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V

    GA-NIFS: JWST/NIRSpec IFU observations of HFLS3 reveal a dense galaxy group at z~6.3

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    Massive, starbursting galaxies in the early Universe represent some of the most extreme objects in the study of galaxy evolution. One such source is HFLS3 (z~6.34), which was originally identified as an extreme starburst galaxy with mild gravitational magnification. Here, we present new observations of HFLS3 with the JWST/NIRSpec IFU in both low (PRISM/CLEAR; R~100) and high spectral resolution (G395H/290LP; R~2700), with high spatial resolution (~0.1") and sensitivity. Thanks to the combination of the NIRSpec data and a new lensing model with accurate spectroscopic redshifts, we find that the 3"x3" field is crowded, with a lensed arc (C, z=6.3425+/-0.0002), two galaxies to the south (S1 and S2, z=6.3592+/-0.0001), two galaxies to the west (W1, z=6.3550+/-0.0001; W2, z=6.3628+/-0.0001), and two low-redshift interlopers (G1, z=3.4806+/-0.0001; G2, z=2.00+/-0.01). We present spectral fits and morpho-kinematic maps for each bright emission line (e.g., [OIII]5007, Halpha, [NII]6584) from the R2700 data for all sources except G2. From a line ratio analysis, the galaxies in C are likely powered by star formation, while we cannot rule out or confirm the presence of AGN in the other high-redshift sources. We perform gravitational lens modelling, finding evidence for a two-source composition of the lensed central object and a comparable magnification factor (mu=2.1-2.4) to previous work. The projected distances and velocity offsets of each galaxy suggest that they will merge within the next ~1Gyr. Finally, we examine the dust extinction-corrected SFR of each z>6 source, finding that the total star formation (460+/-90 Msol/yr, magnification-corrected) is distributed across the six z~6.34-6.36 objects over a region of diameter ~11kpc. Altogether, this suggests that HFLS3 is not a single starburst galaxy, but instead is a merging system of star-forming galaxies in the Epoch of Reionization.Comment: 23 pages, 14 figures, submitted to A&
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