Metallic and insulating interfaces of amorphous SrTiO₃-based oxide heterostructures

The conductance confined at the interface of complex oxide heterostructures provides new opportunities to explore nanoelectronic as well as nanoionic devices. Herein we show that metallic interfaces can be realized in SrTiO(3)-based heterostructures with various insulating overlayers of amorphous LaAlO(3), SrTiO(3), and yttria-stabilized zirconia films. On the other hand, samples of amorphous La(7/8)Sr(1/8)MnO(3) films on SrTiO(3) substrates remain insulating. The interfacial conductivity results from the formation of oxygen vacancies near the interface, suggesting that the redox reactions on the surface of SrTiO(3) substrates play an important role.     

Organogel-Based Emulsion Systems,Micro-Structural Features and Impact on In Vitro Digestion

Organogels based on edible oils and specific mixtures of phytosterols can serve as structured systems with a low saturated fat content. These low-SAFA organogels can be used also to create o/w emulsions. Little is known about the structures formed in these specific organogels and at the emulsion interface. We studied o/w organogels on different length scales to describe and understand their micro-structural features. Very basic processing conditions such as composition, temperature and storage time were taken into account. Two different types of structure were observed; at the smallest scale, long thin crystals are formed out of the oil phase into the continuous water phase. We propose that these are needle-like crystals. Next, tube-like structures are identified and can be visualized as tubular micelles. A model is proposed which fits the dimension (~7 nm) with the length scale of the molecular building blocks (TAGs and sterols). As edible fats from food products are enzymatically hydrolyzed in the gut prior to absorption, we also looked into the impact on the lipase reaction speed. Simple in vitro enzymatic hydrolysis experiments showed a slower enzymatic digestion. Organogel systems and emulsion made thereof have interesting food structuring properties with possible advantages in composition (low SAFA) and digestion speed. All authors were full time employees or trainee (MC) of Unilever during actual execution of this study.     

Senior government executives' use of the internet: A Bruneian scenario

In gearing up the task of e-Government, the governments of the various economies are investing heavily in Information Technology (IT). The success of e-Government program therefore depends upon the IT literacy and skills of the senior government executives, especially in the use of the Internet. This study focuses on 100 senior government executives of the 10 different ministries of Brunei Darussalam. The results indicate that 70% of the senior executives have positive attitudes about the Internet. Results further show that 50% of these senior executives are in fact using the Internet and 66% of them are underutilizing the technology by just sending and receiving e-mails. The study further develops a normative model by using Davis's Technology Acceptance Model (TAM) and by adding external variables. A Structural Equation Modelling technique is used to test the parsimony of the model. The final model has confirmed that external variables, PC self-efficacy and task variety contribute toward both the beliefs perceived usefulness and perceived ease of use. Only perceived ease of use contributes in determining the attitude that further predicts the Internet use of the senior government executives.     

Abstracting and reasoning over ship trajectories and web data with the Simple Event Model (SEM)

Bridging the gap between low-level features and semantics is a problem commonly acknowledged in the Multimedia community. Event modeling can fill this gap by representing knowledge about the data at different level of abstraction. In this paper we present the Simple Event Model (SEM) and its application in a Maritime Safety and Security use case about Situational Awareness, where the data also come as low-level features (of ship trajectories). We show how we abstract over these low-level features, recognize simple behavior events using a Piecewise Linear Segmentation algorithm, and model the resulting events as instances of SEM. We aggregate web data from different sources, apply deduction rules, spatial proximity reasoning, and semantic web reasoning in SWI-Prolog to derive abstract events from the recognized simple events. The use case described in this paper comes from the Dutch Poseidon project.     

Numerical Morphological Modeling of Open-Check Dams

Open-check dams are built in mountain streams to control sediment transport during a flood. Sediment passes through them at the lowest discharges, whereas deposition occurs during the highest discharges. Open-check dams are currently designed based mainly on construction experience. Modeling of hydraulics and bed morphology in check dams involves mixed flows (supercritical and subcritical) as well as discontinuities such as hydraulic jumps. In this paper an unsteady coupled numerical mobile-bed model that can tackle rapid varying flows and discontinuities is applied. The numerical technique is based on the classical staggered grids and implicit integration schemes, together with a proper mass and momentum balance. The 1D numerical model is successfully verified with experimental data of slit-check dams. The applicability of the model in the design of open-check dams is also illustrated.     

Platinum(II) as Bifunctional Linker in Antibody–Drug Conjugate Formation: Coupling of a 4‐Nitrobenzo‐2‐oxa‐1,3‐diazole Fluorophore to Trastuzumab as a Model

The potential of platinum(II) as a bifunctional linker in the coordination of small molecules, such as imaging agents or (cytotoxic) drugs, to monoclonal antibodies (mAbs) was investigated with a 4‐nitrobenzo‐2‐oxa‐1,3‐diazole (NBD) fluorophore and trastuzumab (Herceptin?) as a model antibody. The effect of ligand and reaction conditions on conjugation efficiency was explored for [Pt(en)(L‐NBD)Cl](NO₃) (en=ethylenediamine), with L=N‐heteroaromatic, N‐alkyl amine, or thioether. Conjugation proceeded most efficiently at pH 8.0 in the presence of NaClO₄ or Na₂SO₄ in tricine or HEPES buffer. Reaction of N‐coordinated complexes (20 equiv) with trastuzumab at 37 °C for 2 h, followed by removal of weakly bound complexes with excess thiourea, afforded conjugates with an NBD/mAb ratio of 1.5–2.9 that were stable in phosphate‐buffered saline at room temperature for at least 48 h. In contrast, thioether‐coordinated complexes afforded unstable conjugates. Finally, surface plasmon resonance analysis showed no loss in binding affinity of trastuzumab after conjugation.     

Numerical results of falling film absorption with water/ammonia

A model was set up for the heat, mass and momentum transport in a falling film absorber with a binary gas phase. Results are given for water/ammonia and countercurrent gas flow. If the ratio of diffusion to convection is not negligible (here for a gas channel smaller than 5 mm) absorption is higher with countercurrent gas flow than with cocurrent flow. For larger gas channels the outcomes from a simpler one-component gas phase model are, if the interface boundary conditions are formulated correctly, almost equal to the outcomes from the present model.