Trends in growth and soil nutrients following fire and logging

Understanding the impact of natural and anthropogenic disturbance on soil fertility and tree growth is critical to the sustainability of forest management, yet there remains much uncertainty regarding how both harvesting and wildfire affect soil nutrient dynamics, espe-cially over several decades and in varying overstory types. Historically, wildfire has been the dominant stand-replacing disturbance and an important mechanism of ecosystem renewal. However, intensive forest harvesting is replacing fire as the primary disturbance in many parts of the world, sparking concerns about nutrient depletion and decreased site productivity associated with biomass removals. I conducted a global meta-analysis of northern forest ecosystems to examine the ef-fects of forest harvesting on total concentrations and stoichiometric ratios of soil carbon ([C]), nitrogen ([N]), and phosphorus ([P]) relative to natural, uncut control stands, and whether these effects differed as a function of harvest intensity, soil depth, overstory type, and time since harvesting. I then used an age chronosequence from 7- to 33-years-old to ex-amine and compare the effects of clearcut harvesting and fire on soil nutrient concentrations and tree growth in three predominant upland boreal stand types (dominated by deciduous or coniferous trees, or a combination of both) during early stand development. The results of the meta-analysis indicated that harvesting negatively affects [C], [N], and [P] in the forest floor soil layer, but has positive or neutral effects on the mineral soils layer, except for when it is coupled with fire disturbance (through post-fire salvage logging or prescribed burn following harvest), which resulted in strong, negative effects on mineral soil [C] and [N]. The negative effect of harvesting on forest floor nutrients increased with harvesting intensity. Time since harvesting had a positive effect on soil [C] and [N], but less so for [P], which likely requires more time to recover given its reliance on inputs from min-eral weathering. Our chronosequence study also highlighted the important role of stand age (i.e. time since disturbance). Although fire resulted in more dramatic effects on soil nutrient concentra-tions and stand basal area than harvesting in the 7-year-old stands, these differences con-verged in the 15- and 33-year-old stands. Similar to the meta-analysis, the effects of disturb-ance were most profound in the forest floor layer, and temporal trends differed between bio-logically controlled nutrients (C and N), which recovered rapidly and linearly, and nutrients that are more geochemically controlled (P, K, and Ca). The results of both studies indicated that conifer stands are more sensitive to nutrient loss following disturbance than deciduous stands, and mixedwood stands are intermediate. Our findings highlight the importance of harvest intensity and rotation length on long-term soil nutrient health when managing northern forest ecosystems, particularly in conifer stands

Krebs von den Lungen 6 (KL-6) as a marker for disease severity and persistent radiological abnormalities following COVID-19 infection at 12 weeks

IntroductionAcute presentations of COVID-19 infection vary, ranging from asymptomatic carriage through to severe clinical manifestations including acute respiratory distress syndrome (ARDS). Longer term sequelae of COVID-19 infection includes lung fibrosis in a proportion of patients. Krebs von den Lungen 6 (KL-6) is a mucin like glycoprotein that has been proposed as a marker of pulmonary epithelial cell injury. We sought to determine whether KL-6 was a marker of 1) the severity of acute COVID-19 infection, or 2) the persistence of symptoms/radiological abnormalities at medium term follow up.MethodsProspective single centre observational study.ResultsConvalescent KL-6 levels were available for 93 patients (male 63%, mean age 55.8 years) who attended an 12-week follow up appointment after being admitted to hospital with COVID-19. For 67 patients a baseline KL-6 result was available for comparison. There was no significant correlations between baseline KL-6 and the admission CXR severity score or clinical severity NEWS score. Furthermore, there was no significant difference in the baseline KL-6 level and an initial requirement for oxygen on admission or the severity of acute infection as measured at 28 days. There was no significant difference in the 12-week KL-6 level and the presence or absence of subjective breathlessness but patients with abnormal CT scans at 12 weeks had significantly higher convalescent KL-6 levels compared to the remainder of the cohort (median 1101 IU/ml vs 409 IU/ml).ConclusionsThe association between high KL-6 levels at 12 weeks and persisting CT abnormalities (GGO/fibrosis), is a finding that requires further exploration. Whether KL-6 may help differentiate those patients with persisting dyspnoea due to complications rather than deconditioning or dysfunctional breathing alone, is an important future research question

Exploring the Feasibility of a Self-Managed Lifestyle Intervention, Based on Exercise and Behaviour Support, as an Adjunct Therapy to Compression: A Sub-Study Focusing on People with Venous Leg Ulcers and Early Neuro-Degenerative Diseases (FISCU-NDD)

Background: The aim of this study was to adapt the “FISCU Home” intervention (a co-produced, self-managed and expert-supported lifestyle intervention comprising exercise and behaviour support aimed at people with Venous Leg Ulcers (VLUs), in a way that is suitable for the needs of people with combined VLUs and early-stage, Neuro-degenerative diseases (NDDs), and to explore its feasibility (e.g., estimate rates of recruitment and completion of sessions, calculate study adherence rates, assess participant satisfaction via participant interviews, and assess ease of data collection) within this clinical sub-group. Methods: We recruited seven people belonging to this VLUs sub-group (e.g., people with early-stage dementia or Parkinson’s), who were ≥18 years’ old, had VLU(s) of diameter ≥1 cm, ABPI ≥ 0.8, had the ability to tolerate lower-leg compression and were receiving VLU treatment at home. In Phase 1, participants helped us adapt the intervention. In Phase 2 we carried out a 4-week “training crash-course”. This consisted of three, 1 h, self-managed, exercise sessions per week (12 sessions in total), among the participants that completed the interviews. For Phase 3, we carried out post-interviews with all participants to investigate their study experiences, which were analysed using content analysis. Results: All assessments were completed successfully (100% retention and assessment completion), with no exercise-related adverse events. All participants completed the 4-week intervention (100%; all sessions completed by all participants). Conclusion: Our findings suggest that the adapted intervention is feasible, enjoyable and well-received, and has the potential to provide clinical benefits to the participants

Characterizing 51 Eri b from 1-5 μ\mum: a partly-cloudy exoplanet

We present spectro-photometry spanning 1-5 $\mu$m of 51 Eridani b, a 2-10 M$_\text{Jup}$ planet discovered by the Gemini Planet Imager Exoplanet Survey. In this study, we present new $K1$ (1.90-2.19 $\mu$m) and $K2$ (2.10-2.40 $\mu$m) spectra taken with the Gemini Planet Imager as well as an updated $L_P$ (3.76 $\mu$m) and new $M_S$ (4.67 $\mu$m) photometry from the NIRC2 Narrow camera. The new data were combined with $J$ (1.13-1.35 $\mu$m) and $H$ (1.50-1.80 $\mu$m) spectra from the discovery epoch with the goal of better characterizing the planet properties. 51 Eri b photometry is redder than field brown dwarfs as well as known young T-dwarfs with similar spectral type (between T4-T8) and we propose that 51 Eri b might be in the process of undergoing the transition from L-type to T-type. We used two complementary atmosphere model grids including either deep iron/silicate clouds or sulfide/salt clouds in the photosphere, spanning a range of cloud properties, including fully cloudy, cloud free and patchy/intermediate opacity clouds. Model fits suggest that 51 Eri b has an effective temperature ranging between 605-737 K, a solar metallicity, a surface gravity of $\log$(g) = 3.5-4.0 dex, and the atmosphere requires a patchy cloud atmosphere to model the SED. From the model atmospheres, we infer a luminosity for the planet of -5.83 to -5.93 ($\log L/L_{\odot}$), leaving 51 Eri b in the unique position as being one of the only directly imaged planet consistent with having formed via cold-start scenario. Comparisons of the planet SED against warm-start models indicates that the planet luminosity is best reproduced by a planet formed via core accretion with a core mass between 15 and 127 M$_{\oplus}$.Comment: 27 pages, 19 figures, Accepted for publication in The Astronomical Journa

An analysis of potential barriers and enablers to regulating the television marketing of unhealthy foods to children at the state government level in Australia

Background In Australia there have been many calls for government action to halt the effects of unhealthy food marketing on children\u27s health, yet implementation has not occurred. The attitudes of those involved in the policy-making process towards regulatory intervention governing unhealthy food marketing are not well understood. The objective of this research was to understand the perceptions of senior representatives from Australian state and territory governments, statutory authorities and non-government organisations regarding the feasibility of state-level government regulation of television marketing of unhealthy food to children in Australia.Method Data from in-depth semi-structured interviews with senior representatives from state and territory government departments, statutory authorities and non-government organisations (n=22) were analysed to determine participants\u27 views about regulation of television marketing of unhealthy food to children at the state government level. Data were analysed using content and thematic analyses.Results Regulation of television marketing of unhealthy food to children was supported as a strategy for obesity prevention. Barriers to implementing regulation at the state level were: the perception that regulation of television advertising is a Commonwealth, not state/territory, responsibility; the power of the food industry and; the need for clear evidence that demonstrates the effectiveness of regulation. Evidence of community support for regulation was also cited as an important factor in determining feasibility.Conclusions The regulation of unhealthy food marketing to children is perceived to be a feasible strategy for obesity prevention however barriers to implementation at the state level exist. Those involved in state-level policy making generally indicated a preference for Commonwealth-led regulation. This research suggests that implementation of regulation of the television marketing of unhealthy food to children should ideally occur under the direction of the Commonwealth government. However, given that regulation is technically feasible at the state level, in the absence of Commonwealth action, states/territories could act independently. The relevance of our findings is likely to extend beyond Australia as unhealthy food marketing to children is a global issue.<br /

Towards a European Health Research and Innovation Cloud (HRIC)

The European Union (EU) initiative on the Digital Transformation of Health and Care (Digicare) aims to provide the conditions necessary for building a secure, flexible, and decentralized digital health infrastructure. Creating a European Health Research and Innovation Cloud (HRIC) within this environment should enable data sharing and analysis for health research across the EU, in compliance with data protection legislation while preserving the full trust of the participants. Such a HRIC should learn from and build on existing data infrastructures, integrate best practices, and focus on the concrete needs of the community in terms of technologies, governance, management, regulation, and ethics requirements. Here, we describe the vision and expected benefits of digital data sharing in health research activities and present a roadmap that fosters the opportunities while answering the challenges of implementing a HRIC. For this, we put forward five specific recommendations and action points to ensure that a European HRIC: i) is built on established standards and guidelines, providing cloud technologies through an open and decentralized infrastructure; ii) is developed and certified to the highest standards of interoperability and data security that can be trusted by all stakeholders; iii) is supported by a robust ethical and legal framework that is compliant with the EU General Data Protection Regulation (GDPR); iv) establishes a proper environment for the training of new generations of data and medical scientists; and v) stimulates research and innovation in transnational collaborations through public and private initiatives and partnerships funded by the EU through Horizon 2020 and Horizon Europe

Patterns of Cis Regulatory Variation in Diverse Human Populations

The genetic basis of gene expression variation has long been studied with the aim to understand the landscape of regulatory variants, but also more recently to assist in the interpretation and elucidation of disease signals. To date, many studies have looked in specific tissues and population-based samples, but there has been limited assessment of the degree of inter-population variability in regulatory variation. We analyzed genome-wide gene expression in lymphoblastoid cell lines from a total of 726 individuals from 8 global populations from the HapMap3 project and correlated gene expression levels with HapMap3 SNPs located in cis to the genes. We describe the influence of ancestry on gene expression levels within and between these diverse human populations and uncover a non-negligible impact on global patterns of gene expression. We further dissect the specific functional pathways differentiated between populations. We also identify 5,691 expression quantitative trait loci (eQTLs) after controlling for both non-genetic factors and population admixture and observe that half of the cis-eQTLs are replicated in one or more of the populations. We highlight patterns of eQTL-sharing between populations, which are partially determined by population genetic relatedness, and discover significant sharing of eQTL effects between Asians, European-admixed, and African subpopulations. Specifically, we observe that both the effect size and the direction of effect for eQTLs are highly conserved across populations. We observe an increasing proximity of eQTLs toward the transcription start site as sharing of eQTLs among populations increases, highlighting that variants close to TSS have stronger effects and therefore are more likely to be detected across a wider panel of populations. Together these results offer a unique picture and resource of the degree of differentiation among human populations in functional regulatory variation and provide an estimate for the transferability of complex trait variants across populations

Responses of Southern Ocean seafloor habitats and communities to global and local drivers of change

Knowledge of life on the Southern Ocean seafloor has substantially grown since the beginning of this century with increasing ship-based surveys and regular monitoring sites, new technologies and greatly enhanced data sharing. However, seafloor habitats and their communities exhibit high spatial variability and heterogeneity that challenges the way in which we assess the state of the Southern Ocean benthos on larger scales. The Antarctic shelf is rich in diversity compared with deeper water areas, important for storing carbon (“blue carbon”) and provides habitat for commercial fish species. In this paper, we focus on the seafloor habitats of the Antarctic shelf, which are vulnerable to drivers of change including increasing ocean temperatures, iceberg scour, sea ice melt, ocean acidification, fishing pressures, pollution and non-indigenous species. Some of the most vulnerable areas include the West Antarctic Peninsula, which is experiencing rapid regional warming and increased iceberg-scouring, subantarctic islands and tourist destinations where human activities and environmental conditions increase the potential for the establishment of non-indigenous species and active fishing areas around South Georgia, Heard and MacDonald Islands. Vulnerable species include those in areas of regional warming with low thermal tolerance, calcifying species susceptible to increasing ocean acidity as well as slow-growing habitat-forming species that can be damaged by fishing gears e.g., sponges, bryozoan, and coral species. Management regimes can protect seafloor habitats and key species from fishing activities; some areas will need more protection than others, accounting for specific traits that make species vulnerable, slow growing and long-lived species, restricted locations with optimum physiological conditions and available food, and restricted distributions of rare species. Ecosystem-based management practices and long-term, highly protected areas may be the most effective tools in the preservation of vulnerable seafloor habitats. Here, we focus on outlining seafloor responses to drivers of change observed to date and projections for the future. We discuss the need for action to preserve seafloor habitats under climate change, fishing pressures and other anthropogenic impacts

Characterizing 51 Eri b from 1 to 5 μm : a partly cloudy exoplanet

Funding: This work was supported by NSF grants AST-1411868 (A.R., J.L.P., B.M.), AST-1518332 (R.J.D.R.), and DGE-1311230 (K.W.D.). F.M. and E.N. are supported by NASA Grant NNX14AJ80G. This work was supported by Fonds de Recherche du Québec (J.R., R.D., D.L.). K.M.M. and T.S.B. are supported by the NASA Exoplanets Research Program (XRP) by cooperative agreement NNX16AD44G. G.V. and J.K.W. acknowledge JPL’s ESI program for GPI-related funding.We present spectrophotometry spanning 1–5 μm of 51 Eridani b, a 2–10 MJup planet discovered by the Gemini Planet Imager Exoplanet Survey. In this study, we present new K1 (1.90–2.19 μm) and K2 (2.10–2.40 μm) spectra taken with the Gemini Planet Imager as well as an updated LP (3.76 μm) and new MS (4.67 μm) photometry from the NIRC2 Narrow camera. The new data were combined with J (1.13–1.35 μm) and H (1.50–1.80 μm) spectra from the discovery epoch with the goal of better characterizing the planet properties. The 51 Eri b photometry is redder than field brown dwarfs as well as known young T-dwarfs with similar spectral type (between T4 and T8), and we propose that 51 Eri b might be in the process of undergoing the transition from L-type to T-type. We used two complementary atmosphere model grids including either deep iron/silicate clouds or sulfide/salt clouds in the photosphere, spanning a range of cloud properties, including fully cloudy, cloud-free, and patchy/intermediate-opacity clouds. The model fits suggest that 51 Eri b has an effective temperature ranging between 605 and 737 K, a solar metallicity, and a surface gravity of log(g) = 3.5–4.0 dex, and the atmosphere requires a patchy cloud atmosphere to model the spectral energy distribution (SED). From the model atmospheres, we infer a luminosity for the planet of −5.83 to −5.93 (log L/L⊙), leaving 51 Eri b in the unique position of being one of the only directly imaged planets consistent with having formed via a cold-start scenario. Comparisons of the planet SED against warm-start models indicate that the planet luminosity is best reproduced by a planet formed via core accretion with a core mass between 15 and 127 M⊕.Publisher PDFPeer reviewe

A Giant Planet Candidate Transiting a White Dwarf

Astronomers have discovered thousands of planets outside the solar system, most of which orbit stars that will eventually evolve into red giants and then into white dwarfs. During the red giant phase, any close-orbiting planets will be engulfed by the star, but more distant planets can survive this phase and remain in orbit around the white dwarf. Some white dwarfs show evidence for rocky material floating in their atmospheres, in warm debris disks, or orbiting very closely, which has been interpreted as the debris of rocky planets that were scattered inward and tidally disrupted. Recently, the discovery of a gaseous debris disk with a composition similar to ice giant planets demonstrated that massive planets might also find their way into tight orbits around white dwarfs, but it is unclear whether the planets can survive the journey. So far, the detection of intact planets in close orbits around white dwarfs has remained elusive. Here, we report the discovery of a giant planet candidate transiting the white dwarf WD 1856+534 (TIC 267574918) every 1.4 days. The planet candidate is roughly the same size as Jupiter and is no more than 14 times as massive (with 95% confidence). Other cases of white dwarfs with close brown dwarf or stellar companions are explained as the consequence of common-envelope evolution, wherein the original orbit is enveloped during the red-giant phase and shrinks due to friction. In this case, though, the low mass and relatively long orbital period of the planet candidate make common-envelope evolution less likely. Instead, the WD 1856+534 system seems to demonstrate that giant planets can be scattered into tight orbits without being tidally disrupted, and motivates searches for smaller transiting planets around white dwarfs.Comment: 50 pages, 12 figures, 2 tables. Published in Nature on Sept. 17, 2020. The final authenticated version is available online at: https://www.nature.com/articles/s41586-020-2713-