144 research outputs found
Tolerable versus actual soil erosion rates in Europe
Erosion is a major threat to soil resources in Europe, and may impair their ability to deliver a range of ecosystem goods and services. This is reflected by the European Commission's Thematic Strategy for Soil Protection, which recommends an indicator-based approach for monitoring soil erosion. Defined baseline and threshold values are essential for the evaluation of soil monitoring data. Therefore, accurate spatial data on both soil loss and soil genesis are required, especially in the light of predicted changes in climate patterns, notably frequency, seasonal distribution and intensity of precipitation. Rates of soil loss are reported that have been measured, modelled or inferred for most types of soil erosion in a variety of landscapes, by studies across the spectrum of the Earth sciences. Natural rates of soil formation can be used as a basis for setting tolerable soil erosion rates, with soil formation consisting of mineral weathering as well as dust deposition. This paper reviews the concept of tolerable soil erosion and summarises current knowledge on rates of soil formation, which are then compared to rates of soil erosion by known erosion types, for assessment of soil erosion monitoring at the European scale
Special Section Guest Editorial:Thirty Years of Functional Near-Infrared Spectroscopy
5R24NS104096-04 - NIH/National Institute of Neurological Disorders & Stroke; 3U01EB029856-04S1 REVISED - NIH/National Institute of Biomedical Imaging & Bioengineerinhttp://10.0.4.93/1.NPh.10.2.023501Published versio
Upcoming Neurophotonics Status Report
Forthcoming status report articles provide updates on microscopy and on diffuse optical imaging in neurophotonics
Do temperature and moisture conditions impact soil microbiology and aggregate stability?
Purpose: Studies predicting the impacts of climate change on erosion have considered numerous variables, such as rainfall erosivity and vegetation cover, but have not considered potential changes in soil erodibility. Erodibility is an intrinsic property of the soil, strongly correlated with the stability of soil aggregates. It is influenced by soil physico-chemical attributes, including the microbiological community. The study aim was to determine how shifts in temperature and moisture conditions, which other studies have shown affect microbiological communities, might affect aggregate stability.
Methods: Using an experimental approach with laboratory microcosms, aggregates from a sandy loam soil and a clay soil were incubated at three temperatures and three moisture conditions in a factorial experimental design. Aggregate stability was quantified using rainfall simulation. Microbiological indicator metrics were measured to evaluate treatment microbiological impacts, including community composition (PLFA), biomass carbon, and respiration.
Results: Temperature and moisture content affected aggregate stability significantly, but differently for the two soil types tested. For the sandy loam soil, aggregate stability decreased significantly with increasing moisture content. For the clay soil, aggregate stability increased significantly with increasing temperature. For both soil textures, temperature and moisture content affected microbiological community composition and respiration. Regression analysis indicated that microbiological properties were significant predictors of aggregate stability.
Conclusion: Our results emphasise the dynamic nature of soil aggregate stability. Changes in microbiological metrics suggest possible biological mechanisms for aggregate stability changes, which should be investigated further to better understand the potential impacts of climate change on soil erodibility and erosion.Natural Environment Research Council (NERC): NE-M009106-1
BBSR
Blood flow response to orthostatic challenge identifies signatures of the failure of static cerebral autoregulation in patients with cerebrovascular disease
Autorregulació cerebral; Malaltia cerebrovascular; Òptica difusaAutorregulación cerebral; Enfermedad cerebrovascular; Óptica difusaCerebral autoregulation; Cerebrovascular disease; Diffuse opticsBackground
The cortical microvascular cerebral blood flow response (CBF) to different changes in head-of-bed (HOB) position has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS) technique. However, the relationship between these relative ΔCBF changes and associated systemic blood pressure changes has not been studied, even though blood pressure is a major driver of cerebral blood flow.
Methods
Transcranial DCS data from four studies measuring bilateral frontal microvascular cerebral blood flow in healthy controls (n = 15), patients with asymptomatic severe internal carotid artery stenosis (ICA, n = 27), and patients with acute ischemic stroke (AIS, n = 72) were aggregated. DCS-measured CBF was measured in response to a short head-of-bed (HOB) position manipulation protocol (supine/elevated/supine, 5 min at each position). In a sub-group (AIS, n = 26; ICA, n = 14; control, n = 15), mean arterial pressure (MAP) was measured dynamically during the protocol.
Results
After elevated positioning, DCS CBF returned to baseline supine values in controls (p = 0.890) but not in patients with AIS (9.6% [6.0,13.3], mean 95% CI, p < 0.001) or ICA stenosis (8.6% [3.1,14.0], p = 0.003)). MAP in AIS patients did not return to baseline values (2.6 mmHg [0.5, 4.7], p = 0.018), but in ICA stenosis patients and controls did. Instead ipsilesional but not contralesional CBF was correlated with MAP (AIS 6.0%/mmHg [− 2.4,14.3], p = 0.038; ICA stenosis 11.0%/mmHg [2.4,19.5], p < 0.001).
Conclusions
The observed associations between ipsilateral CBF and MAP suggest that short HOB position changes may elicit deficits in cerebral autoregulation in cerebrovascular disorders. Additional research is required to further characterize this phenomenon.The funders did not have any role in study design, execution and data interpretation. This work was funded by Redes Temáticas de Investigación Cooperativa (RETICS-INVICTUS RD012/0014 and RD16/0019/0010), Fundació CELLEX Barcelona, Ministerio de Economía y Competitividad/FEDER (PHOTODEMENTIA, PHOTOMETABO, DPI2015–64358-C2–1-R, PRE2018-085082), Instituto de Salud Carlos III/FEDER (FIS PI09/0557, MEDPHOTAGE, DTS16/00087), the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0522), the Obra Social “la Caixa” Foundation (LlumMedBcn), Institució “Centres de Recerca de Catalunya”, “Agència de Gestió d’Ajuts Universitaris i de Recerca”-Generalitat (2017SGR-1380), LASERLAB-EUROPE IV (EU-H2020 654148), Whitaker International Program of the Institute for International Education, T32 HL007954 Multidisciplinary training in cardiovascular biology, Marie Curie initial training network (OILTEBIA 317526), Marie Sklowdowska-Curie-COFUND (H2020, ICFOstepstone 2, 71329), “Fundació La Marató TV3” (201709.30, 201709.31), São Paulo Research Foundation (FAPESP) through 2012/02500–8 and National Institutes of Health (R01-NS060653, K24-NS058386, R24-HD050836, P41-EB015893, DP2-HD101400, U54-HD086984)
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