“Crashing the gates” – selection criteria for television news reporting of traffic crashes

This study investigates which crash characteristics influence the probability that the crash is reported in the television news. To this purpose, all news items from the period 2006–2012 about traffic crashes from the prime time news of two Belgian television channels are linked to the official injury crash database. Logistic regression models are built for the database of all injury crashes and for the subset of fatal crashes to identify crash characteristics that correlate with a lower or higher probability of being reported in the news.     

Attenuated total internal reflection infrared microscopy of multilayer plastic packaging foils

Multilayer plastic foils are important packaging materials that are used to extend the shelf life of food products and drinks. Fourier transform infrared (FT-IR) spectroscopic imaging using attenuated total internal reflection (ATR) can be used for the identification and localization of different layers in multilayer foils. A new type of ATR crystal was used in combination with a linear array detector through which large sample areas (400 x 400 microm(2)) could be imaged with a pixel size of 1.6 microm. The method was tested on laminated plastic packing materials containing 5 to 12 layers. The results of the identification of the different materials using ATR-FT-IR were compared with differential scanning calorimetry (DSC) and the layer thickness of the individual layers measured by ATR-FT-IR was compared with polarized light microscopy (LM) and scanning electron microscopy (SEM). It has been demonstrated that individual layers with a thickness of about 3 microm could be identified in multilayer foils with a total thickness ranging from 100 to 150 microm. The results show a spatial resolution of about 4 microm (measured at wavenumbers ranging from 1000 to 1730 cm(-1)), which is about a factor of two better than can be obtained using transmission FT-IR imaging. An additional advantage of ATR is the ease of sample preparation. A good correspondence was found between visible and FT-IR images. The results of ATR-FT-IR imaging were in agreement with those obtained by LM, SEM, and DSC. ATR-FT-IR is superior to the combination of these techniques because it delivers both spatial and chemical information.     

The Measurement of Neutron Cross Sections for Contrast-Enhancing Penetrant Fluids

Abstract

The purpose of this experiment was to evaluate penetrant fluids of high neutron cross section. These fluids are useful in neutron radiographic investigations for contrast enhancement. Saturated solutions of the gadolinium salts and one chelate were formed by using one of several solvents, and the resulting fluid's macroscopic neutron cross sections were measured experimentally.

The results of this experiment provided a quantitative measure of the mean and standard deviation of the macroscopic neutron cross section for the penetrant fluids. In addition, a confidence interval was generated for each fluid. The measured neutron cross section for a control fluid was in close agreement with published values.     

The analysis of halogenated acetic acids in dutch drinking water

Halo-acetic acids are produced during chlorine disinfection of drinking water. Besides the well-known dichloro-, and trichloroacetic acid, brominated and mixed chloro/bromo acetic acids are also produced. A method was developed to determine all halo-acetic acids. This method was applied for the analysis of 20 drinking waters prepared from different source waters. Halo-acetic acids were found in all drinking waters prepared from surface water while they could not be detected in drinking waters prepared from ground water. The acid concentrations were in the range of 0–14.7 μg/l and dibromoacetic acid was found to be the most prominent halo-acetic acid in chlorinated waters. Brominated acetic acids accounted for 65% of the total acid concentration showing that brominated compounds form a large part of the chlorination products. The total halo-acetic acid concentration correlated positively with the chlorine-to-carbon ratio and with the adsorbable organic halogen, to which it accounted for 15%.     

A Computationally Efficient Method for Determining the Size and Location of Myocardial Ischemia

The purpose of this paper is to introduce a new method for solving the inverse problem of locating ischemic regions in the heart. The electrical activity in the human heart is modeled by the bidomain equations, which can be expanded to compute the potentials on the body surface. The associated inverse problem is to use ECG recordings to gain information about ischemias. We propose an algorithm for doing this, combining the level set method with a simpler minimization problem. Instead of trying to determine the shape, as in the level set method, we simply make the approximation that the ischemia is spherical. The effects of ischemia on the electrical attributes of heart tissue are examined. The new method is tested with computer simulations on synthetic body surface potential maps (BSPMs) in a realistic geometry, using realistic values for the parameters. It is shown to be, in some respects, superior to the level set approach and may be a step toward a practical algorithm useful in medical diagnostics.     

Automated estimation of initial and terminal contact timing using accelerometers; development and validation in transtibial amputees and controls.

The aim of this study was to develop and validate an automated accelerometry-based system for estimating initial contact (IC) and terminal contact (TC) timing information from walking patterns of healthy control subjects and transtibial amputees that can be used in daily life with minimal interference of researchers. Subjects were instrumented with two uniaxial accelerometers just below the knee while synchronized ground reaction force (GRF) recordings were used as reference measurements. An automated multiphase algorithm was developed to estimate the time of IC and TC in the acceleration signals of five healthy subjects and two transtibial amputees walking at different walking speeds. The accuracy of the detection algorithm in ten control subjects and eight transtibial amputees indicated mean errors ranging between 0.013 and 0.034 s for the TC and IC timing, with 95 % confidence interval of the individual step errors ranging between -0.062 and 0.115 s. Correlation coefficients between the estimated stance phase duration and GRF data were 0.98 and 0.97 for controls and amputees, respectively. We concluded that IC and TC can be accurately and easily measured using this system in both healthy subjects and transtibial amputees walking at different walking speeds. The system can be used in clinical situations or gait labs as well as during daily life.     

Multiscale modeling in food engineering

Since many years food engineers have attempted to describe physical phenomena such as heat and mass transfer that occur in food during unit operations by means of mathematical models. Foods are hierarchically structured and have features that extend from the molecular scale to the food plant scale. In order to reduce computational complexity, food features at the fine scale are usually not modeled explicitly but incorporated through averaging procedures into models that operate at the coarse scale. As a consequence, detailed insight into the processes at the microscale is lost, and the coarse scale model parameters are apparent rather than physical parameters. As it is impractical to measure these parameters for the large number of foods that exist, the use of advanced mathematical models in the food industry is still limited. A new modeling paradigm – multiscale modeling – has appeared that may alleviate these problems. Multiscale models are essentially a hierarchy of sub-models which describe the material behavior at different spatial scales in such a way that the sub-models are interconnected. In this article we will introduce the underlying physical and computational concepts. We will give an overview of applications of multiscale modeling in food engineering, and discuss future prospects.     

3D‐printed external light trap for solar cells

We present a universally applicable 3D‐printed external light trap for enhanced absorption in solar cells. The macroscopic external light trap is placed at the sun‐facing surface of the solar cell and retro‐reflects the light that would otherwise escape. The light trap consists of a reflective parabolic concentrator placed on top of a reflective cage. Upon placement of the light trap, an improvement of 15% of both the photocurrent and the power conversion efficiency in a thin‐film nanocrystalline silicon (nc‐Si:H) solar cell is measured. The trapped light traverses the solar cell several times within the reflective cage thereby increasing the total absorption in the cell. Consequently, the trap reduces optical losses and enhances the absorption over the entire spectrum. The components of the light trap are 3D printed and made of smoothened, silver‐coated thermoplastic. In contrast to conventional light trapping methods, external light trapping leaves the material quality and the electrical properties of the solar cell unaffected. To explain the theoretical operation of the external light trap, we introduce a model that predicts the absorption enhancement in the solar cell by the external light trap. The corresponding calculated path length enhancement shows good agreement with the empirically derived value from the opto‐electrical data of the solar cell. Moreover, we analyze the influence of the angle of incidence on the parasitic absorptance to obtain full understanding of the trap performance. © 2015 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons, Ltd.     

Improvement of traditional processing of local monkey orange (<Emphasis Type="Italic">Strychnos</Emphasis> spp.) fruits to enhance nutrition security in Zimbabwe

Although the monkey orange (Strychnos spp.) tree fruit is widely distributed in Southern Africa and particularly in Zimbabwe, it is underutilized and little attention has been given to its potential commercialisation due to limited knowledge and information. Most of the fruits and their products are wasted because of limited harvest time, process control and storage conditions, leading to variability in shelf life and sensory quality, thereby impacting nutritional quality. Traditional processing techniques make insufficient use of this food resource within rural communities. This study aimed at identifying the existing bottlenecks by means of a survey among 102 smallholder farming respondents in the wet and dry regions of Zimbabwe. Results revealed that S. cocculoides and S. spinosa were used by 48% of respondents as a functional ingredient in porridge, by 25% in fermented mahewu drink and by 15% of respondents as a non-alcoholic juice. The fruits of S. innocua and S. madagascariensis are preferably processed into dried products. Taste, flavour and colour were the important quality characteristics for all processed products, and constraints to be solved are seed-flesh separation, long processing times, separation of juice and pulp during storage as well as pulp viscosity. Respondents reported monkey orange products to have health benefits for children and immune-compromised people, who, on regular consumption, have reportedly increased weight and resistance to disease. The positive perception about the processed products of Strychnos spp. offer a good opportunity to improve nutrition security by capitalizing on these not-yet-fully-exploited resources, but technological solutions to improve sensory quality and shelf life must be developed.