Rapid Screening of Operational Freshwater Availability Using Global Models

Freshwater shortage already affects large parts of the world, and is expected to increase rapidly over the coming decades as a result of increased water demands and the impacts of climate change. Global-scale water risk or stress maps are available online, but these lack quantitative information on local freshwater availability, rendering them unsuitable for water risk assessment from an operational perspective, i.e. when comparing water availability to a specific quantified water demand (in m³s^?1 rather than generic risk indicators). Therefore, our main goal was to develop a rapid screening method to estimate current and future operational freshwater availability using global-scale models. Operational Freshwater Availability (OFWA) was computed using the PCR-GLOBWB global hydrology and water resources model, coupled to a global MODFLOW groundwater model. PCR-GLOBWB was forced with rainfall and temperature fields from the IPSL-CM5A-LR climate model under the RCP6.0 climate scenario, with water demands based on the SSP2 socio-economic scenario. Unique to our study are the downscaling of the coupled PCR-GLOBWB-MODFLOW model to 90 m resolution and the provision of quantitative estimates on long term trends in operational freshwater availability. Our results showed a high, i.e. operationally relevant, accuracy for operational surface water availability, while the uncertainty about operational groundwater availability remained high due to limited availability of subsurface data. With this method, we developed a modelling capacity for rapidly generating scenario-based water availability projections with operational relevance in a rigorous, systematic way, such that it enables like-for-like comparisons. Further refinement is required for accurate estimates of operational groundwater availability.     

Performance evaluation of SDN-controlled green mobile fronthaul using a federation of experimental network testbeds

Photonic Network Communications - When evolved NodeB flexible functional split is implemented in virtualized radio access network 5G systems, fronthaul connectivity between the virtualized network...     

Physical modeling of systems involving electromagnetic heating ofmaterials

The technique of physical scale modeling of electromagnetic problems that include heat generation is described. The scaling groups required for modeling, which depend on the ratio of conduction to displacement currents, are derived from simple physical arguments which are suitable for presentation to undergraduates in a first course on Mawell's equations. The modeling of some practical problems is considered, and the approximations that must be made to the scaling groups to solve these problems are discussed. Three special cases are considered in some depth. In the first case conduction current greatly dominates the current flow in the full-scale system (such heating can be referred to as resistive heating). In the second case both conduction and displacement currents are significant. In the third case conduction current is much greater than displacement current and the system dimensions are comparable to or greater than the wavelength and depth of penetration     

Accelerated and Improved Vascular Maturity after Transplantation of Testicular Tissue in Hydrogels Supplemented with VEGF- and PDGF-Loaded Nanoparticles

Avascular transplantation of frozen–thawed testicular tissue fragments represents a potential future technique for fertility restoration in boys with cancer. A significant loss of spermatogonia was observed in xeno-transplants of human tissue most likely due to the hypoxic period before revascularization. To reduce the effect of hypoxia–reoxygenation injuries, several options have already been explored, like encapsulation in alginate hydrogel and supplementation with nanoparticles delivering a necrosis inhibitor (NECINH) or VEGF. While these approaches improved short-term (5 days) vascular surfaces in grafts, neovessels were not maintained up to 21 days; i.e., the time needed for achieving vessel stabilization. To better support tissue grafts, nanoparticles loaded with VEGF, PDGF and NECINH were developed. Testicular tissue fragments from 4–5-week-old mice were encapsulated in calcium-alginate hydrogels, either non-supplemented (control) or supplemented with drug-loaded nanoparticles (VEGF-nanoparticles; VEGF-nanoparticles + PDGF-nanoparticles; NECINH-nanoparticles; VEGF-nanoparticles + NECINH-nanoparticles; and VEGF-nanoparticles + PDGF-nanoparticles + NECINH-nanoparticles) before auto-transplantation. Grafts were recovered after 5 or 21 days for analyses of tissue integrity (hematoxylin–eosin staining), spermatogonial survival (immuno-histo-chemistry for promyelocytic leukemia zinc finger) and vascularization (immuno-histo-chemistry for α-smooth muscle actin and CD-31). Our results showed that a combination of VEGF and PDGF nanoparticles increased vascular maturity and induced a faster maturation of vascular structures in grafts.     

Micro-hydrodynamic effects in EBT textured steel sheet

The paper describes the tribological behaviour in the steel sheet and die contact occurring in deep drawing applications. In more detail, sheet surfaces produced by the EBT (Electron Beam Textured) process have been investigated, both theoretical and experimental. By a stepwise theoretical analysis, it is demonstrated that a substantial part of the load supported by sheet surface can be generated by micro-hydrodynamic effects on the curved hills of the sheet surface. Thereto, an original concept of dominant summits has been introduced in order to distinguish from the classical definition of a roughness “peak”. It is shown that the latter fails in explaining the experimental behaviour, both in friction and in galling. The new approach clearly demonstrates its potential for a better modelling of the tribo-behaviour.     

Influence of temperature and pH on the kinetics of the Sharon nitritation process

The SHARON (Single reactor High activity Ammonia Removal Over Nitrite) process is an innovative process that improves the sustainability of wastewater treatment, especially when combined with an Anammox process. It aims at ammonium oxidation to nitrite only, while preventing further nitrate formation. In order to optimize this process by means of modelling and simulation, parameters of the biological processes have to be assessed. Batch tests with SHARON sludge clearly showed that ammonia rather than ammonium is the actual substrate and nitrous acid rather than nitrite is the actual inhibitor of the ammonium oxidation in the SHARON process. From these batch tests the ammonia affinity constant, the nitrous acid inhibition constant and the oxygen affinity constant were determined to be 0.75 mgNH₃‐N L^?1, 2.04 mgHNO₂‐N L^?1 and 0.94 mgO₂ L^?1. The influence of pH and temperature on the oxygen uptake rate of SHARON biomass was determined, indicating the existence of a pH interval between 6.5 and 8 and a temperature interval from 35 to 45 °C where the biomass activity is maximal. The kinetic parameters of the SHARON process were determined based on batch experiments. These parameters can now be implemented in a simulation model for further optimization of the SHARON process. Copyright © 2007 Society of Chemical Industry     

Spectral Characterization of a Digital Still Camera's NIR Modification to Enhance Archaeological Observation

Scholars using still cameras to take (mostly) oblique imagery from a low-flying aircraft of various possible archaeologically related anomalies can be defined as aerial archaeologists. At present, as well as in the past, aerial/air archaeology has been acquiring data almost exclusively in the visible range of the electromagnetic spectrum. This phenomenon can largely be attributed to the critical imaging process and sometimes unconvincing results related to the film-based approach of near-infrared (NIR) photography. To overcome the constraints of detecting and interpreting only the varying visible colors in vegetation (the so-called crop marks), while still maintaining the flexible and low-cost approach characteristic for aerial archaeology, a consumer digital still camera was modified to capture NIR radiation. By its spectral characterization, more insight was gained into its imaging properties and necessary guidelines for data processing, and future improvements could be formulated, all in an attempt to better capture the archaeologically induced anomalous growth stresses in crops.     

An anticipatory approach to optimal experimental design for model discrimination

The problem of model discrimination arises when several models are proposed to describe one and the same process. To identify the best model from the set of rival models, it may be necessary to collect new information about the process, and thus additional experiments have to be performed. This paper deals with the experimental design methodologies that are used to find the experimental conditions that allow to discriminate among rival models with the least experimental effort. For this, the expected experimental results should be predicted differently by the rival models, and the uncertainty on the measurements and on the model predictions should not be too large. These aspects were included in the approach developed by Buzzi-Ferraris and co-workers [G. Buzzi-Ferraris, P. Forzatti, G. Emig, H. Hofmann, Sequential experimental design procedure for model discrimination in the case of multiple responses. Chemical Engineering Science (1) (1984) 81–85], but in their approach the uncertainties are estimated from the information content of the already performed experiments. This work presents a modification of the Buzzi-Ferraris approach in which the expected information content of the newly designed experiment is considered, even before the experiment is performed (anticipatory design). In this way, a better estimate of the uncertainties is achieved, and an experiment with an increased discriminatory potential is obtained. The approaches were illustrated and compared by applying them to a case study in which two rival models are proposed to describe the in vitro kinetics of an enzyme.     

Miniaturization of a homogeneous fluorescence immunoassay based on energy transfer using nanotiter plates as high-density sample carriers.

The miniaturization of a homogeneous competitive immunoassay to a final assay volume of 70 nL is described. As the sample carrier, disposable plastic nanotiter plates (NTP) with dimensions of 2 x 2 cm2 containing 25 x 25 wells, corresponding to approximately 15,000 wells on a traditional 96-well microtiter plate footprint, were used. Sample handling was accomplished by a piezoelectrically actuated micropipet. To reduce evaporation while pipetting the assays, the NTP was handled in a closed humid chamber and cooled to the point of condensation. To avoid washing steps, a homogeneous assay was developed that was based on energy-transfer (ET). As a model system, an antibody-based assay for the detection of the environmentally relevant compound, simazine, in drinking water was chosen. Antibodies were labeled with the long-wavelength-excitable sulfoindocyanine dye Cy5 (donor), and a tracer was synthesized by labeling BSA with a triazine derivative and the acceptor dye Cy5.5. At low analyte concentrations, the tracer was preferably bound to the antibody binding sites. As a result of the close proximity of Cy5.5 and Cy5, an efficient quenching of the Cy5 fluorescence occurred. Higher analyte concentrations led to a progressive binding of the analyte to the antibody binding sites. The increased Cy5 fluorescence was determined by using a scanning laser-induced fluorescence detector. The limit of detection (LOD), using an antibody concentration of 20 nM, was 0.32 microg/L, or 1.11 x 10(-16) mol of simazine. In comparison, the LOD of the 96-well microtiter-plate-based ET immunoassay (micro-ETIA) was 0.15 microg/L, or 1.87 x 10(-13) mol. The LOD of the optimized micro-ETIA at 1 nM IgG, was 0.01 microg/L.     

Effects of different <Emphasis Type="Italic">Lactobacillus</Emphasis> and <Emphasis Type="Italic">Enterococcus</Emphasis> strains and chemical acidification regarding degradation of gluten proteins during sourdough fermentation

Dough quality and baking performance of wheat dough are significantly affected by the qualitative and quantitative composition of the gluten. Therefore, the degradation was studied of specific fractions of gluten proteins in sourdough as affected by starter cultures. Doughs were fermented for 0, 5, and 24 h at 30 °C after addition of Lactobacillus sakei, L. plantarum, L. sanfranciscensis or Enterococcus faecalis. Chemically acidified doughs were used as controls. All doughs were analyzed quantitatively for their content of albumins, globulins, gliadins, glutenins, and glutenin macropolymer by means of a combined extraction/HPLC procedure. Protein degradation during sourdough fermentation was primarily due to acidic proteases present in flour. While L. sakei, L. plantarum and L. sanfranciscensis were mostly non-proteolytic, E. faecalis clearly contributed to gluten proteolysis. Single gluten protein types were clearly different in their resistance to proteolytic activities of the dough system and E. faecalis, and, in contrast to total glutenins, the amounts of gluten macropolymer were significantly reduced already after 5 h of incubation. When longer fermentation times were applied, gluten was substantially degraded. The strongest decrease was found for the glutenin fraction leading to an increase of alcohol soluble oligomeric proteins in the gliadin fraction. The extent of the decrease of monomeric gliadins was strongest for the γ-type followed by the α- and the ω-types. This indicates that dough properties residing in specific types of gluten fractions can be influenced by the duration of fermentation and the application of proteolytic strains.