Response of Quercus robur and two potential climate change winners— Quercus pubescens and Quercus ilex —To two years summer drought in a semi-controlled competition study: I—Tree water status

To prevent severe loss in the economic and ecological value of Central European forestland in the context of climate change and therefore seasonal water shortage, a 'human aided migration' with suitable species is recommended. Mediterranean oaks might cope better with Climate Change and even become increasingly competitive in Central Europe compared to other tree species. Therefore, we compared the functional and ecological strategies to endure soil drought of 9-year-old half-deciduous Quercus pubescens and evergreen Quercus ilex and their competitiveness to the local deciduous Quercus robur, using a semi-controlled setup with the possibility to control the groundwater level (large lysimeter basins filled with a loamy soil). We analyzed responses to repetitive (2014, 2015) drought stress (DS) for approximately four months, monitoring relative leaf water content (LWC), predawn water potential (Psi(PD)), sap flow rates, the rooting depth (by deuterium-enriched water uptake) and a proxy for biomass increases by measuring the stem diameter 5 cm above the ground (D05), and compared the results to a well-watered control treatment (CO).In 2014, significant differences between the CO and DS treatments were only visible in Q. robur. In 2015, a longer drought period in combination with extremely high temperatures in summer led to a more profound drying out of the soil under DS. Therefore, all three species showed drought responses, with WpD levels dropping below -2 MPa and LWC values dropping below 80% LWC. Sap flow rates of DS plants were also reduced compared to CO treatments. Q. robur showed the strongest response with Psi(PD), below - 3 MPa and premature senescence. In contrast to these physiological measurements, we could not detect differences between CO and DS plants in the 005 increase and root depth for Q. ilex and Q. pubescens, only Q. robur DS displayed strong reductions in both values comparing to CO. The response for Q. robur has already been described, but the equal performance of CO and DS plants of Q. pubescens and Q. ilex contrasts previous analyses, which award evergreen oaks, like Q. ilex, a higher maximal stomatal conductance and less embolism under DS than deciduous oaks. Interestingly, both, Q. ilex and Q. pubescens, did not show a significant reduction of growth under drought (D05, rooting depth) in our lysimeter setup, despite their significant DS responses in LWC, sap flow and Psi(PD)

Lessons from the 2018-2019 European droughts: a collective need for unifying drought risk management

Drought events and their impacts vary spatially and temporally due to diverse pedo-climatic and hydrologic conditions, as well as variations in exposure and vulnerability, such as demographics and response actions. While hazardous severity and frequency of past drought events have been studied in detail, little is known about the effect of drought management strategies on the actual impacts, and how the hazard is perceived by relevant stakeholders for inducing action. In a continental study, we characterised and assessed the impacts and the perceptions of two recent drought events (2018 and 2019) in Europe and examined the relationship between management strategies and drought perception, hazard and impacts. The study was based on a pan-European survey involving national representatives from 28 countries and relevant stakeholders responding to a standard questionnaire. The survey focused on collecting information on stakeholders’ perceptions of drought, impacts on water resources and beyond, water availability and current drought management strategies at national and regional scales. The survey results were compared with the actual drought hazard information registered by the European Drought Observatory (EDO) for 2018 and 2019. The results highlighted high diversity in drought perceptions across different countries and in values of implemented drought management strategies to alleviate impacts by increasing national and sub-national awareness and resilience. The study concludes with an urgent need to further reduce drought impacts by constructing and implementing a European macro-level drought governance approach, such as a directive, which would strengthen national drought management and lessen harm to human and natural potentials

A genomic catalog of Earth’s microbiomes

The reconstruction of bacterial and archaeal genomes from shotgun metagenomes has enabled insights into the ecology and evolution of environmental and host-associated microbiomes. Here we applied this approach to >10,000 metagenomes collected from diverse habitats covering all of Earth’s continents and oceans, including metagenomes from human and animal hosts, engineered environments, and natural and agricultural soils, to capture extant microbial, metabolic and functional potential. This comprehensive catalog includes 52,515 metagenome-assembled genomes representing 12,556 novel candidate species-level operational taxonomic units spanning 135 phyla. The catalog expands the known phylogenetic diversity of bacteria and archaea by 44% and is broadly available for streamlined comparative analyses, interactive exploration, metabolic modeling and bulk download. We demonstrate the utility of this collection for understanding secondary-metabolite biosynthetic potential and for resolving thousands of new host linkages to uncultivated viruses. This resource underscores the value of genome-centric approaches for revealing genomic properties of uncultivated microorganisms that affect ecosystem processes.</p

Reproducibility of fluorescent expression from engineered biological constructs in E. coli

We present results of the first large-scale interlaboratory study carried out in synthetic biology, as part of the 2014 and 2015 International Genetically Engineered Machine (iGEM) competitions. Participants at 88 institutions around the world measured fluorescence from three engineered constitutive constructs in E. coli. Few participants were able to measure absolute fluorescence, so data was analyzed in terms of ratios. Precision was strongly related to fluorescent strength, ranging from 1.54-fold standard deviation for the ratio between strong promoters to 5.75-fold for the ratio between the strongest and weakest promoter, and while host strain did not affect expression ratios, choice of instrument did. This result shows that high quantitative precision and reproducibility of results is possible, while at the same time indicating areas needing improved laboratory practices.Peer reviewe

Clinical and genetic characteristics of late-onset Huntington's disease

Background: The frequency of late-onset Huntington's disease (&gt;59 years) is assumed to be low and the clinical course milder. However, previous literature on late-onset disease is scarce and inconclusive. Objective: Our aim is to study clinical characteristics of late-onset compared to common-onset HD patients in a large cohort of HD patients from the Registry database. Methods: Participants with late- and common-onset (30–50 years)were compared for first clinical symptoms, disease progression, CAG repeat size and family history. Participants with a missing CAG repeat size, a repeat size of ≤35 or a UHDRS motor score of ≤5 were excluded. Results: Of 6007 eligible participants, 687 had late-onset (11.4%) and 3216 (53.5%) common-onset HD. Late-onset (n = 577) had significantly more gait and balance problems as first symptom compared to common-onset (n = 2408) (P &lt;.001). Overall motor and cognitive performance (P &lt;.001) were worse, however only disease motor progression was slower (coefficient, −0.58; SE 0.16; P &lt;.001) compared to the common-onset group. Repeat size was significantly lower in the late-onset (n = 40.8; SD 1.6) compared to common-onset (n = 44.4; SD 2.8) (P &lt;.001). Fewer late-onset patients (n = 451) had a positive family history compared to common-onset (n = 2940) (P &lt;.001). Conclusions: Late-onset patients present more frequently with gait and balance problems as first symptom, and disease progression is not milder compared to common-onset HD patients apart from motor progression. The family history is likely to be negative, which might make diagnosing HD more difficult in this population. However, the balance and gait problems might be helpful in diagnosing HD in elderly patients