856 research outputs found
Representing composition, spatial structure and management intensity of European agricultural landscapes: A new typology
Comprehensive maps that characterize the variation in agricultural landscapes across Europe are lacking. In this paper we present a new Europe-wide, spatially-explicit typology and inventory of the diversity in composition, spatial structure and management intensity of European agricultural landscapes. Agricultural landscape types were characterized at a 1 k
Exploring tranquillity experienced in landscapes based on social media
This work was financially supported by the Swiss National Science Foundation [grant no. 171911] and the European Union's Horizon 2020 research and innovation programme [grant agreement no. 689,812] (‘LandSense’).Peer reviewedPublisher PD
Modelling regional land change scenarios to assess land abandonment and reforestation dynamics in the Pyrenees (France)
International audienceOver the last decades and centuries, European mountain landscapes have experienced substantial transformations. Natural and anthropogenic LULC changes (land use and land cover changes), especially agro-pastoral activities, have directed influenced the spatial organization and composition of European mountain landscapes. For the past 60 years, natural reforestation has been occurring due to a decline in both agricultural production activities and rural population. Stakeholders, to better anticipate future changes, need spatially and temporally explicit models to identiy areas at risk of land change and possible abandonment. This paper presents an integrated approach combining forecasting scenarios and a LULC changes simulation model to assess where LULC changes may occur in the Pyrenees Mountains, based on historical LULC trands and a range of future socio-economic drivers. The proposed methodology considers local specificities of Pyrenan valleys, sub-regional climate and topographical properties, and regional economic policies. Results indicate that some regions are projected to face strong abandonment, regardless of scenario conditions. Overall, high rates of change are associated with administrative regions where land productivity is highly dependent on socio-economic drivers and climatic and environmental conditions limit intensive (agricultural and/or pastoral) production and profitability. The combination of the results for the four scenarios allows assessements of where encroachment (e.g. colonization by shrublands) and reforestation are the most probable. This assessment intends to provide insight into the potential future development of the Pyrenees to help identify areas that are the most sensitive to change and to guide decision makers to help their management decisions
Experimental validation of model for pulsed laser-induced subsurface modifications in Si
Wafers are traditionally diced with diamond saw blades. Saw dicing technology has a number of limitations, especially concerning the dicing of thin wafers. Moreover, the use of fluids and the gen-eration of debris can damage fragile components such as micro electro-mechanical systems. Laser ablation dicing is better suited for thin wafers, but is also not a clean process. An alternative dicing method is subsurface laser dicing. This technology is based on the production of laser-induced sub-surface modifications inside the wafer. These modifications weaken the material, such that the wafer separates along the planes with laser modifications when applying an external force. To find the right laser conditions to produce subsurface modifications in silicon, and to enhance the understand-ing of the underlying physics, a numerical model has previously been developed. To validate this model, the current work compares simulation results with experimental data obtained by focusing nano- and picosecond pulses inside silicon wafers. A fairly good agreement between experimental and numerical results was obtaine
Van denken naar doen: ecosysteemdiensten in de praktijk
In dit rapport is de beleidsuitvoering van de ecosysteemdienstenbenadering onderzocht in vier gebieden in het Verenigd Koninkrijk, in één gebied in Vlaanderen. Verder is de toepassing van de benadering door Natuurmonumenten en de Dienst Landelijk Gebied in verschillende Nederlandse cases en gebieden onderzocht. Uit het onderzoek blijkt dat het TEEB-raamwerk op een andere wijze wordt uitgevoerd dan wordt aanbevolen. Belanghebbenden in alle onderzochte gebieden vinden de technische taal te complex en passen alternatieven toe. De verwachting dat de waardering van diensten kan leiden naar een markt van vraag en aanbod wordt niet waargemaakt. In alle gevallen wordt gewerkt met overheidssubsidies en die gevallen waar wel een particuliere vraag is, volgen directe betalingen. Er is weinig kennis over de effecten van ecosysteemdiensten op de biodiversiteit. Het is niet helder of ecosysteemdiensten bijdragen aan de bescherming van biodiversiteit
Crystal structure of laser-induced subsurface modifications in Si
Laser-induced subsurface modification of dielectric materials is a well-known technology. Applications include the production of optical components and selective etching. In addition to dielectric materials, the subsurface modification technology can be applied to silicon, by employing near to mid-infrared radiation. An application of subsurface modifications in silicon is laser-induced subsurface separation, which is a method to separate wafers into individual dies. Other applications for which proofs of concept exist are the formation of waveguides and resistivity tuning. However, limited knowledge is available about the crystal structure of subsurface modifications in silicon. In this work, we investigate the geometry and crystal structure of laser-induced subsurface modifications in monocrystalline silicon wafers. In addition to the generation of lattice defects, we found that transformations to amorphous silicon and Si-iii/Si-xii occur as a result of the laser irradiatio
Determining Toxic Potencies of Water-Soluble Contaminants in Wastewater Influents and Effluent Using Gene Expression Profiling in C. elegans as a Bioanalytical Tool
With chemical analysis, it is impossible to qualify and quantify the toxic potency of especially hydrophilic bioactive contaminants. In this study, we applied the nematode C. elegans as a model organism for detecting the toxic potency of whole influent wastewater samples. Gene expression in the nematode was used as bioanalytical tool to reveal the presence, type and potency of molecular pathways induced by 24-h exposure to wastewater from a hospital (H), nursing home (N), community (C), and influent (I) and treated effluent (E) from a local wastewater treatment plant. Exposure to influent water significantly altered expression of 464 genes, while only two genes were differentially expressed in nematodes treated with effluent. This indicates a significant decrease in bioactive pollutant-load after wastewater treatment. Surface water receiving the effluent did not induce any genes in exposed nematodes. A subset of 209 genes was differentially expressed in all untreated wastewaters, including cytochromes P450 and C-type lectins related to the nematode's xenobiotic metabolism and immune response, respectively. Different subsets of genes responded to particular waste streams making them candidates to fingerprint-specific wastewater sources. This study shows that gene expression profiling in C. elegans can be used for mechanism-based identification of hydrophilic bioactive compounds and fingerprinting of specific wastewaters. More comprehensive than with chemical analysis, it can demonstrate the effective overall removal of bioactive compounds through wastewater treatment. This bioanalytical tool can also be applied in the process of identification of the bioactive compounds via a process of toxicity identification evaluation. [GRAPHICS]
New first trimester crown-rump length's equations optimized by structured data collection from a French general population
--- Objectives --- Prior to foetal karyotyping, the likelihood of Down's
syndrome is often determined combining maternal age, serum free beta-HCG,
PAPP-A levels and embryonic measurements of crown-rump length and nuchal
translucency for gestational ages between 11 and 13 weeks. It appeared
important to get a precise knowledge of these scan parameters' normal values
during the first trimester. This paper focused on crown-rump length. ---
METHODS --- 402 pregnancies from in-vitro fertilization allowing a precise
estimation of foetal ages (FA) were used to determine the best model that
describes crown-rump length (CRL) as a function of FA. Scan measures by a
single operator from 3846 spontaneous pregnancies representative of the general
population from Northern France were used to build a mathematical model linking
FA and CRL in a context as close as possible to normal scan screening used in
Down's syndrome likelihood determination. We modeled both CRL as a function of
FA and FA as a function of CRL. For this, we used a clear methodology and
performed regressions with heteroskedastic corrections and robust regressions.
The results were compared by cross-validation to retain the equations with the
best predictive power. We also studied the errors between observed and
predicted values. --- Results --- Data from 513 spontaneous pregnancies allowed
to model CRL as a function of age of foetal age. The best model was a
polynomial of degree 2. Datation with our equation that models spontaneous
pregnancies from a general population was in quite agreement with objective
datations obtained from 402 IVF pregnancies and thus support the validity of
our model. The most precise measure of CRL was when the SD was minimal
(1.83mm), for a CRL of 23.6 mm where our model predicted a 49.4 days of foetal
age. Our study allowed to model the SD from 30 to 90 days of foetal age and
offers the opportunity of using Zscores in the future to detect growth
abnormalities. --- Conclusion --- With powerful statistical tools we report a
good modeling of the first trimester embryonic growth in the general population
allowing a better knowledge of the date of fertilization useful in the
ultrasound screening of Down's syndrome. The optimal period to measure CRL and
predict foetal age was 49.4 days (9 weeks of gestational age). Our results open
the way to the detection of foetal growth abnormalities using CRL Zscores
throughout the first trimester
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