Urbanization alters natural hydrological processes and enhances runoff, which affects flood hazard. Interest in nature-based solutions (NBS) for sustainable mitigation and adaptation to urban floods ...is growing, but the magnitudes of NBS effects are still poorly investigated. This study explores the potential of NBS for flood hazard mitigation in a small peri-urban catchment in central Portugal, prone to flash floods driven by urbanization and short but intense rainfall events typical of the Mediterranean region. Flood extent and flood depth are assessed by manually coupling the hydrologic HEC-HMS and hydraulic HEC-RAS models. The coupled model was run for single rainfall events with recurrence periods of 10–, 20–, 50–, and 100–years, considering four simulation scenarios: current conditions (without NBS), and with an upslope NBS, a downslope NBS, and a combination of both. The model-simulation approach provides good estimates of flood magnitude (NSE = 0.91, RMSE = 0.08, MAE = 0.07, R2 = 0.93), and shows that diverting streamflow into abandoned fields has positive impacts in mitigating downslope flood hazard. The implementation of an upslope NBS can decrease the water depth at the catchment outlet by 0.02 m, whereas a downslope NBS can reduce it from 0.10 m to 0.23 m for increasing return periods. Combined upslope and downslope NBS have a marginal additional impact in reducing water depth, ranging from 0.11 m to 0.24 m for 10– and 100–year floods. Decreases in water depth provided by NBS are useful in flood mitigation and adaptation within the peri-urban catchment. A network of NBS, rather than small isolated strategies, needs to be created for efficient flood-risk management at a larger scale.
Despite only 8% of cattle being found in Europe, European breeds dominate current genetic resources. This adversely impacts cattle research in other important global cattle breeds, especially those ...from Africa for which genomic resources are particularly limited, despite their disproportionate importance to the continent's economies. To mitigate this issue, we have generated assemblies of African breeds, which have been integrated with genomic data for 294 diverse cattle into a graph genome that incorporates global cattle diversity. We illustrate how this more representative reference assembly contains an extra 116.1 Mb (4.2%) of sequence absent from the current Hereford sequence and consequently inaccessible to current studies. We further demonstrate how using this graph genome increases read mapping rates, reduces allelic biases and improves the agreement of structural variant calling with independent optical mapping data. Consequently, we present an improved, more representative, reference assembly that will improve global cattle research.
Gallium-nitride (GaN)-based light-emitting diodes (LEDs) are highly efficient sources for general purpose illumination. Visible light communications (VLC) uses these sources to supplement existing ...wireless communications by offering a large, licence-free region of optical spectrum. Here, we report on progress in the development of micro-scale GaN LEDs (micro-LEDs), optimized for VLC. These blue-emitting micro-LEDs are shown to have very high electrical-to-optical modulation bandwidths, exceeding 800 MHz. The data transmission capabilities of the micro-LEDs are illustrated by demonstrations using ON-OFF-keying, pulse-amplitude modulation, and orthogonal frequency division multiplexing modulation schemes to transmit data over free space at the rates of 1.7, 3.4, and 5 Gb/s, respectively.
Society depends on goods and services provided by ecosystems, not only for survival but also for general wellbeing. Over the last decades, peri-urban areas have been subject to the pressure of ...urbanization and, thus, land-use changes. These changes modify the natural ecosystems and their ability to support human security and safety, but the extent of these impacts is not well-known. This study investigates the impact of five decades of land-use changes in potential ecosystem services (ESs) supply, in the peri-urban Ribeira dos Covões catchment, located in the periphery of Coimbra one of the largest cities in central Portugal. Based on eight land-use maps from 1958 to 2012, the ESs were estimated through a quantification matrix developed by local stakeholders. The expansion of urban and forest areas from 7% to 40% and from 43% to 55%, respectively, mostly through the occupation of agriculture fields (reduced from 48% to 4%), together with changes in the type of forest area (from mixed to commercial broad-leaved), led to a 73% reduction in the ESs potential supply. This reduction was driven by major losses in regulation but also provisioning services. Catchment management and urban planning should be supported by ESs assessment in order to mitigate the negative impacts on regulation, provisioning and cultural services provided by the ecosystems, and thus maximize the benefits for society.
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•Urbanization has adverse impacts on the potential supply of ecosystem services (ESs)•The conversion of forest into urban land-use has more detrimental impacts on ESs than the occupation of agriculture fields•The expansion of forestry can partially compensate the impacts of urbanization on ESs•Wildfire has a major impact on ESs potential supply than discontinuous urbanization•Mapping ESs should integrate urban planning to achieve sustainable development
Background
A Task Force was convened by the EFNS/MDS‐ES Scientist Panel on Parkinson's disease (PD) and other movement disorders to systemically review relevant publications on the diagnosis of PD.
...Methods
Following the EFNS instruction for the preparation of neurological diagnostic guidelines, recommendation levels have been generated for diagnostic criteria and investigations.
Results
For the clinical diagnosis, we recommend the use of the Queen Square Brain Bank criteria (Level B). Genetic testing for specific mutations is recommended on an individual basis (Level B), taking into account specific features (i.e. family history and age of onset). We recommend olfactory testing to differentiate PD from other parkinsonian disorders including recessive forms (Level A). Screening for pre‐motor PD with olfactory testing requires additional tests due to limited specificity. Drug challenge tests are not recommended for the diagnosis in de novo parkinsonian patients. There is an insufficient evidence to support their role in the differential diagnosis between PD and other parkinsonian syndromes. We recommend an assessment of cognition and a screening for REM sleep behaviour disorder, psychotic manifestations and severe depression in the initial evaluation of suspected PD cases (Level A). Transcranial sonography is recommended for the differentiation of PD from atypical and secondary parkinsonian disorders (Level A), for the early diagnosis of PD and in the detection of subjects at risk for PD (Level A), although the technique is so far not universally used and requires some expertise. Because specificity of TCS for the development of PD is limited, TCS should be used in conjunction with other screening tests. Conventional magnetic resonance imaging and diffusion‐weighted imaging at 1.5 T are recommended as neuroimaging tools that can support a diagnosis of multiple system atrophy (MSA) or progressive supranuclear palsy versus PD on the basis of regional atrophy and signal change as well as diffusivity patterns (Level A). DaTscan SPECT is registered in Europe and the United States for the differential diagnosis between degenerative parkinsonisms and essential tremor (Level A). More specifically, DaTscan is indicated in the presence of significant diagnostic uncertainty such as parkinsonism associated with neuroleptic exposure and atypical tremor manifestations such as isolated unilateral postural tremor. Studies of 123IMIBG/SPECT cardiac uptake may be used to identify patients with PD versus controls and MSA patients (Level A). All other SPECT imaging studies do not fulfil registration standards and cannot be recommended for routine clinical use. At the moment, no conclusion can be drawn as to diagnostic efficacy of autonomic function tests, neurophysiological tests and positron emission tomography imaging in PD.
Conclusions
The diagnosis of PD is still largely based on the correct identification of its clinical features. Selected investigations (genetic, olfactory, and neuroimaging studies) have an ancillary role in confirming the diagnosis, and some of them could be possibly used in the near future to identify subjects in a pre‐symptomatic phase of the disease.
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Wildfires represent an important agent of land degradation in temperate sub-humid ecosystems, including southern European Mediterranean countries. Identification of integrated conservation approaches ...that can reduce or prevent degradational impacts is the aim of the EU-funded DESIRE research program, part of which is concerned with quantifying the likely benefit of acceptable alternative conservation strategies to wildfire. The overall aim of this paper is to apply a modification of the Pan-European Soil Erosion Risk Assessment (PESERA) model in order to compare predicted soil erosion rates of one possible conservation strategy, the regular application of prescribed fire, with that of wildfire. The model is applied to two fire-prone study areas in central Portugal (Góis and Mação) and predicts runoff and erosion at much larger spatial (regional) and temporal (decadal) scales than is usually possible with field monitoring. Simulation using the model was carried out for 50years based on a historical climate time-series. Even assuming very frequent management burns (every 2years) and infrequent wildfires (100years), the model suggests that this conservation measure can generally reduce soil erosion relative to infrequent wildfires, although the predicted soil losses for both types of fire are large compared even with those obtained from small-scale field monitoring. The benefits, limitations, scope for improvement and application to future climatic scenarios of the model in a fire context are discussed.
► Post-fire main modelled effects: loss of vegetation, increasing soil erodibility. ► Modelling of forest fire dynamics and post-fire recovery is still exploratory. ► Further analysis of field data for the study sites is still needed. ► PESERA appears to over-estimate post-fire soil erosion of thin stony soils. ► Promising alternative route for assessing medium- to long-term impacts of wildfires.
Abstract
Spatial arrangement of distinct Amazonian environments through time and its effect on specialized biota remain poorly known, fueling long-lasting debates about drivers of biotic ...diversification. We address the late Quaternary sediment deposition that assembled the world's largest seasonally flooded ecosystems. Genome sequencing was used to reconstruct the demographic history of bird species specialized in either early successional vegetation or mature floodplain forests. Sediment deposition that built seasonally flooded habitats accelerated throughout the Holocene (last 11,700 years) under sea level highstand and intensification of the South American Monsoon, at the same time as global increases in atmospheric methane concentration. Bird populations adapted to seasonally flooded habitats expanded due to enlargement of Amazonian river floodplains and archipelagos. Our findings suggest that the diversification of the biota specialized in seasonally flooded habitats is coupled to sedimentary budget changes of large rivers, which rely on combined effects of sea level and rainfall variations.
AIMS: Soil water repellency (SWR) in Mediterranean sub-humid environments is poorly studied in soils derived from basic bedrock. This study addressed this gap by comparing SWR in soil samples ...collected before/after a prescribed burning in a Mediterranean shrubland overlaying limestone. METHODS: Sampling was performed on two adjacent slopes (NE/SW) underneath Quercus coccifera, Pistacia lentiscus, Arbutus unedo shrubs, and on bare inter-patches, at two depths (0–2 and 2–5 cm). Samples were sieved at <0.25, 0.25–1, 1–2 and <2 mm and SWR was assessed through the Water Drop Penetration Time (WDPT) in each fraction. Samples were analysed for pH, AS, CaCO₃ and SOM. RESULTS: SWR was present before fire, mainly in the <0.25 and 0.25–1 mm fractions at 0–2 cm, which could be explained by SOM (amount and chemical composition). Persistence varied between the two slopes (NE > SW) and the four patches (Arbutus unedo > Pistacia lentiscus ≈ Quercus coccifera > Bare). The low-severity fire slightly increased SWR but did not affect the above-mentioned pre-fire differences. CONCLUSIONS: The wax and resins from different shrub species have implications for SWR persistence on the finer soil fractions. Prescribed fire increased the severity of SWR at surface but also its frequency at the subsurface layer.
Prescribed (controlled) fire has recently been adopted as an important wildfire-fighting strategy in the Mediterranean. Relatively little research, however, has assessed its impacts on soil erosion ...and soil quality. This paper investigates hillslope-scale losses of soil, organic matter and selected nutrients before and after a ‘worst-case scenario’ prescribed fire in a steep, shrub-vegetated catchment with thin stony soil in central Portugal. Comparison is made with soil erosion measured: (1) on a nearby hillslope burned by wildfire and monitored at the hillslope scale; and (2) on long-unburned terrain at small-plot, hillslope- and catchment-scales. Hillslope-scale pre- and post-fire soil erosion was recorded over periods of 6weeks to 5months for (1) 9.5months pre-fire and 27months post-fire in the prescribed fire catchment, and (2) c. 3years post-fire at the wildfire site. Organic matter content, pH, total N, K2O, P2O5, Ca2+ and Mg2+ were measured in the eroded sediment and in pre- and post-prescribed fire surface soil. Results indicate that: (1) both the prescribed fire and the wildfire caused expected marked increases in erosion compared with unburned terrain; and (2) the hillslope-scale post-prescribed fire soil losses (up to 2.41tha−1yr−1) exceeded many reported plot-scale post-prescribed fire and post-wildfire erosion rates in the Mediterranean. As a comparison, post-fire erosion for both fire types was less than that caused by some other forms of common soil disturbance (e.g. types of tillage) and even that on undisturbed shrubland in low rainfall areas of the region. Total estimated post-prescribed fire particulate losses of organic matter and nutrients represent only 0.2–2.9% of the content in the upper 2cm of soil, suggesting only a modest fire effect on soil quality, although this may reflect in part a lack of extreme rainfall events following the fire. The longer-term implications for soil conservation of repeated prescribed fire in the Mediterranean are explored and future research priorities identified.
•Prescribed fire impacts on soil degradation at the hillslope-scale are presented.•3-year losses of soil, organic matter and nutrients are reported.•Losses are not serious for this individual fire in central Portugal.•Losses are low compared with some agricultural land-uses.•Implications of repeated prescribed fire for soil quality are examined.
Galileons are scalar field theories which obey the Galileon symmetry φ→φ+b+cμxμ and are capable of self-acceleration if they have an inverted sign for the kinetic term. These theories violate the ...strong equivalence principle, such that black holes (BHs) do not couple to the Galileon field, whereas nonrelativistic objects experience a fifth force with strength ΔG/GN relative to gravity. For galaxies falling down a gradient in the Galileon field, this results in an offset between the center of the galaxy and its host supermassive BH. We reconstruct the local gravitational and Galileon fields through a suite of constrained N-body simulations (which we dub CSiBORG) and develop a Monte Carlo-based forward model for these offsets on a galaxy-by-galaxy basis. Using the measured offset between the optical center and active galactic nucleus of 1916 galaxies from the literature, propagating uncertainties in the input quantities and marginalizing over an empirical noise model describing astrophysical and observational noise, we constrain the Galileon coupling to be ΔG/GN<0.16 at 1σ confidence for Galileons with crossover scale rC≳H0−1.
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