Latent risk and trend models for the evolution of annual fatality numbers in 30 European countries

In this paper a unified methodology is presented for the modelling of the evolution of road safety in 30 European countries. For each country, annual data of the best available exposure indicator and of the number of fatalities were simultaneously analysed with the bivariate latent risk time series model. This model is based on the assumption that the amount of exposure and the number of fatalities are intrinsically related. It captures the dynamic evolution in the fatalities as the product of the dynamic evolution in two latent trends: the trend in the fatality risk and the trend in the exposure to that risk. Before applying the latent risk model to the different countries it was first investigated and tested whether the exposure indicator at hand and the fatalities in each country were in fact related at all. If they were, the latent risk model was applied to that country; if not, a univariate local linear trend model was applied to the fatalities series only, unless the latent risk time series model was found to yield better forecasts than the univariate local linear trend model. In either case, the temporal structure of the unobserved components of the optimal model was established, and structural breaks in the trends related to external events were identified and captured by adding intervention variables to the appropriate components of the model. As a final step, for each country the optimally modelled developments were projected into the future, thus yielding forecasts for the number of fatalities up to and including 2020.     

Synchrotron infrared microspectroscopy detecting the evolution of Huntington's disease neuropathology and suggesting unique correlates of dysfunction in white versus gray brain matter

Huntington's disease (HD), caused by a mutation of the corresponding gene encoding the protein huntingtin (htt), is characterized by progressive deterioration of cognitive and motor functions, paralleled by extensive loss of striatal neurons. At the cellular level, pathogenesis involves an early and prolonged period of neuronal dysfunction followed by neuronal death. Understanding the molecular events driving these deleterious processes is critical to the successful development of therapies to slow down or halt the progression of the disease. Here, we examined biochemical processes in a HD ex vivo rat model, as well as in a HD model for cultured neurons using synchrotron-assisted Fourier transform infrared microspectroscopy (S-FTIRM). The model, based on lentiviral-mediated delivery of a fragment of the HD gene, expresses a mutant htt fragment in one brain hemisphere and a wild-type htt fragment in the control hemisphere. S-FTIRM allowed for high spatial resolution and distinction between spectral features occurring in gray and white matter. We measured a higher content of β-sheet protein in the striatal gray matter exposed to mutant htt as early as 4 weeks following the initiation of mutant htt exposure. In contrast, white matter tracts did not exhibit any changes in protein structure but surprisingly showed reduced content of unsaturated lipids and a significant increase in spectral features associated with phosphorylation. The former is reminiscent of changes consistent with a myelination deficiency, while the latter is characteristic of early pro-apoptotic events. These findings point to the utility of the label-free FTIRM method to follow mutant htt's β-sheet-rich transformation in striatal neurons ex vivo, provide further evidence for mutant htt amyloidogenesis in vivo, and demonstrate novel chemical features indicative of white matter changes in HD. Parallel studies in cultured neurons expressing the same htt fragments showed similar changes.     

Simple colorimetric method for quantification of surface carboxy groups on polymer particles

We present a novel, simple, and fast colorimetric method to quantify the total number of carboxy groups on polymer microparticle and nanoparticle surfaces. This method exploits that small divalent transition metal cations (M(2+) = Ni(2+), Co(2+), Cd(2+)) are efficiently bound to these surface functional groups, which allows their extraction by a single centrifugation step. Remaining M(2+) in the supernatant is subsequently quantified spectrophotometrically after addition of the metal ion indicator pyrocatechol violet, for which Ni(2+) was identified to be the most suitable transition metal cation. We demonstrate that the difference between added and detected M(2+) is nicely correlated to the number of surface carboxy groups as determined by conductometry, thereby affording a validated measure for the trueness of this procedure. The variation coefficient of ~5% found in reproducibility studies underlines the potential of this novel method that can find conceivable applications for the characterization of different types of poly(carboxylic acid)-functionalized materials, e.g., for quality control by manufacturers of such materials.     

Using UV Photography to Reduce Use of Tanning Booths: A Test of Cognitive Mediation.

Two laboratory studies were conducted in which a new type of intervention was used to reduce ultraviolet radiation (UV) exposure from tanning booth use among college students (Time 1 Ns=70 and 134). The intervention uses UV photography to highlight the damage to facial skin caused by previous UV exposure. When the authors controlled for baseline measures of booth use, students in both studies who viewed their UV photographs reported less booth use at a follow-up session 3-4 weeks later than did students not shown a copy of their photograph. Also, in both studies, the decline in use was significantly mediated by a Tanning Cognition Index composed of variables suggested by the prototype-willingness (prototype) model of health risk: tanning attitudes, tanner prototypes, and willingness to engage in risky UV exposure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Integrating a formal method into a software engineering process with UML and Java

We describe how CSP-OZ, a formal method combining the process algebra CSP with the specification language Object-Z, can be integrated into an object-oriented software engineering process employing the UML as a modelling and Java as an implementation language. The benefit of this integration lies in the rigour of the formal method, which improves the precision of the constructed models and opens up the possibility of (1) verifying properties of models in the early design phases, and (2) checking adherence of implementations to models. The envisaged application area of our approach is the design of distributed reactive systems. To this end, we propose a specific UML profile for reactive systems. The profile contains facilities for modelling components, their interfaces and interconnections via synchronous/broadcast communication, and the overall architecture of a system. The integration with the formal method proceeds by generating a significant part of the CSP-OZ specification from the initially developed UML model. The formal specification is on the one hand the starting point for verifying properties of the model, for instance by using the FDR model checker. On the other hand, it is the basis for generating contracts for the final implementation. Contracts are written in the Java Modeling Language (JML) complemented by CSP_jassda, an assertion language for specifying orderings between method invocations. A set of tools for runtime checking can be used to supervise the adherence of the final Java implementation to the generated contracts. This research was partially supported by the DFG project ForMooS (grants OL 98/3-2 and WE 2290/5-1). C. B. Jones     

Imprcved Fast Neutron Tolerance of GaAs JFET's Operating in the Hot Electron Range

The fast neutron induced degradation of the electrical characteristics of n-channel GaAs junction field effect transistors (JFET's) operating in the Shockley mode (thermal equilibrium) was estimated previously. Advances in technology have led to the fabrication of devices with micron sized channel lengths which are capable of response at microwave frequencies. Short channel lengths, however, result in device operation under thermal nonequilibrium conditions and hot electron effects must be considered. The theory of Lehovec and Zuleeg, which provides the characteristics for JFET's operating in the hot electron range, is employed in this paper to estimate the neutron degradation of these devices. It is shown that JFET's operating in the hot electron range are more resistant to neutron exposure than are JFET's operating in the Shockley region. Devices with channel doping concentration of 1017 cm-3 are predicted to survive fluences of 1016 neutrons/cm2. Some preliminary test results are reported.     

Emulsifier Composition of Solid Lipid Nanoparticles (SLN) Affects Mechanical and Barrier Properties of SLN‐Protein Composite Films

Protein films can be applied to improve food quality and to reduce packaging waste. To overcome their poor water barrier properties, lipids are often incorporated. The function of incorporated lipid depends on the interface between filler and matrix. This study aimed to tailor the properties of a protein–lipid film by designing the oil/water interface to see if the concept of inactive/active filler is valid. Therefore, we varied the emulsifier stabilizing solid lipid nanoparticles (SLN) to promote (via β‐lactoglobulin) or to minimize (via Tween 20) interactions between particle surface and protein. SLN were incorporated into protein films and film properties were determined. Addition of SLN led to significantly decreased water vapor permeability (WVP) of protein films. However, WVP was mainly affected by the emulsifiers and not by the lipid. Protein‐stabilized SLN (BS) replaced a lacking protein in the protein network and therefore did not influence the mechanical properties of the films at ambient temperature. BS‐composite films were temperature sensitive, as lipid and sucrose palmitate melted at temperatures above 40 °C. Tween 20‐stabilized SLN (TS) led to reduced tensile strengths, probably due to perturbative effects of TS and plasticizing effects of Tween 20. Dynamic mechanical analysis showed that TS and Tween 20 increased film mobility. Melting of lipid and emulsifiers, and temperature‐dependent behavior of Tween 20 led to a strong temperature dependence of the film stiffness. By designing the interface, particles can be used to tailor mechanical properties of protein films. Tuned edible films could be used to control mass transfers between foods.     

Effect of wheat bran on the mechanical properties of extruded starchy foams

Incorporation of wheat bran has a significant effect on the texture of extruded starchy products. This can be explained by changes in the mechanical parameters of the products. The stress at rupture and elastic modulus of wheat flour-based solid foams, obtained at different extrusion conditions and bran concentration, were measured using a three-point bending test. Both parameters were positively correlated with the foam relative density according to the Gibson–Ashby model. At same relative densities and bran concentration, finer structures with higher density of small cells led to a higher mechanical strength of the foams. The stress at rupture of the unexpanded material was decreased when increasing the bran concentration. Nevertheless, expanded foams with added bran at an intermediate level showed increased mechanical strength. This was attributed to the finer cellular structures obtained. The effect of increasing the bran to a higher concentration on the mechanical properties was depending on the cell wall thickness and bran particle dimensions. At high relative density, the strength of the foams was further increased due to the even finer structures obtained. At low relative density, even though finer structures were also obtained, the stress at rupture of the foams was decreased. This may be explained by the lower cell wall thicknesses and low adhesion properties between bran and starch favoring rupture of the cell walls.