Search results

Filter

Filetype

Your search for "*" yielded 533765 hits

Resistivity imaging and image analysis for estimating water and solute transport across the capillary fringe in laboratory experiments

This study contains a series of laboratory experiments designed to describe the lateral movement and spatial variability of an infiltrated dye tracer across the capillary fringe of homogenous sand in an aquarium. A combination of image analysis and geoelectrical monitoring was used to track the flow paths of the dye with different hydraulic gradients and infiltration rates. Photographs were taken

Solute transport and water content measurements in clay soils using time domain reflectometry

Clayey and saline soils have been shown to be problematic for time domain reflectometry (TDR) measurements. This study presents some of these problems and discusses solutions to them. Thirteen solute transport experiments were carried out in three undisturbed soil columns of swelling clay soil from Tunisia, labelled S1, S2, and S3 respectively. The columns were collected at three different physiog

Monthly runoff prediction using phase-space reconstruction

A nonlinear prediction method, developed based on the ideas gained from deterministic chaos theory, is employed: (a) to predict monthly runoff; and (b) to detect the possible presence of chaos in runoff dynamics. The method first reconstructs the single-dimensional (or variable) runoff series in a multi-dimensional phase space to represent its dynamics, and then uses a local polynomial approach to

A long-lasting taxonomic problem in European Sympycnus resolved, with the description of a new species and data on habitat preferences

Type specimens of Sympycnus pulicarius, S. annulipes, S. cinerellus and S. desoutteri were examined to clear up a long-lasting taxonomic confusion. Our study revealed that they represent, together with S. pygmaeus and S. annulipes var. brunnitibialis, a single species, with S. pulicarius as the senior subjective synonym, which is redescribed in this paper. Lectotypes were designated for Dolichopus

Modeling plot scale dye penetration by a diffusion limited aggregation (DLA) model

Solute transport in the unsaturated zone often occurs in preferential How paths. There are several reasons for this, e.g., water repellency, the occurrence of fissures and cracks, animal borrows, decomposed root threads etc. The resulting How patterns often display a fractal resemblance which is difficult to predict using conventional transport models. A way to preserve the fractal property of obs

Effects of the adsorption of NOM model molecules on the aggregation of TiO2 nanoparticles in aqueous suspensions

Interaction of synthetic TiO2 (anatase) nanoparticles in aqueous suspension at pH 5 was investigated as a function of time in the presence of various organic molecules in terms of adsorption and aggregation behaviour. ζ-potential and average particle diameter were determined with electrophoretic and dynamic light scattering, respectively, while batch adsorption experiments were used to quantify th

Sources of uncertainty in modeled land carbon storage within and across three MIPs : Diagnosis with three new techniques

Terrestrial carbon cycle models have incorporated increasingly more processes as a means to achieve more-realistic representations of ecosystem carbon cycling. Despite this, there are large across-model variations in the simulation and projection of carbon cycling. Several model intercomparison projects (MIPs), for example, the fifth phase of the Coupled Model Intercomparison Project (CMIP5) (hist

On roundoff error growth in elliptic problems

Large-scale linear systems arise in finite-difference and finite-element discretizations of elliptic problems. With increasing computer performance, ever larger systems are solved using direct methods. How large can such systems be without roundoff compromising accuracy? Here we model roundoff dynamics in standard LU and LDLT decompositions with respect to problem size N. For the one-dimensional (

Eight new species of Dolichopodinae (Diptera: Dolichopodidae) from northern Iran

Dipterological surveys were conducted in different sites in western and central parts of northern Iran (Guilan, Mazandaran, Kordestan, East and West Azerbaijan and Ardabil provinces) during 2010–2011 using Malaise traps, and during 2012–2014 employing sweep nets. A total of 110 species were collected, including 42 Dolichopodinae. Eleven dolichopodine species proved new to science, eight of which a

The Nazis’ cloven hoof : Finnish critiques of legal sterilisation

In 1935, a law on prescription-based sterilisation of ‘the idiot, the imbecile, and the mentally ill’ was passed by a majority in the Finnish parliament. Complementary of earlier eugenic legislation, it was considered beneficial for public health and economy, following the examples of ‘advanced’ countries such as Sweden and Germany. The cultural journal Tulenkantajat (The Fire Bearers, 1932-1939)

Hydrological Climate Change Impact Assessment at Small and Large Scales: Key Messages from Recent Progress in Sweden

Hydrological climate change impact assessment is generally performed by following a sequence of steps from global and regional climate modelling, through data tailoring (bias-adjustment and downscaling) and hydrological modelling, to analysis and impact assessment. This “climate-hydrology-assessment chain” has been developed with a primary focus on applicability to a medium-sized rural basin, whic

Antithrombotic therapy after myocardial infarction in patients with atrial fibrillation undergoing percutaneous coronary intervention

Aims Optimal antithrombotic therapy after percutaneous coronary intervention (PCI) in patients with myocardial infarction (MI) and atrial fibrillation is uncertain. In this study, we compared antithrombotic regimes with regard to a composite cardiovascular outcome of all-cause mortality, MI or ischaemic stroke, and major bleeds. Methods and results Patients between October 2005 and December 2012 w

Women with fear of childbirth might benefit from having a known midwife during labour

Aim: Having a known midwife at birth is valued by women across the world, however it is unusual for women with fear of childbirth to have access to this model of care. The aim of this study was to describe the prevalence and factors related to having access to a known midwife for women referred to counseling due to childbirth fear. We also wanted to explore if women's levels of childbirth fear cha

The positive net radiative greenhouse gas forcing of increasing methane emissions from a thawing boreal forest‐wetland landscape

At the southern margin of permafrost in North America, climate change causes widespread permafrost thaw. In boreal lowlands, thawing forested permafrost peat plateaus (‘forest’) lead to expansion of permafrost‐free wetlands (‘wetland’). Expanding wetland area with saturated and warmer organic soils is expected to increase landscape methane (CH4) emissions. Here, we quantify the thaw‐induced increa