A Tobit Analysis of WIC Children's Consumption of Pyramid Group Foods

This paper develops and estimates an econometric model for children's consumption of the Pyramid Group foods using the Continuing Survey of Food Intake by Individuals (CSFII) for the years 1994-96, 1998. This analysis is accomplished using a Tobit model (censored dependent variable) and by appropriately incorporating the survey design characteristics. Results of the regression analysis indicate that participation in the WIC program significantly affects the consumption patterns of children, for certain types of Pyramid Group foods. After controlling for other factors, WIC children consumed more milk, fruit and whole grain and less of added sugar than the group of eligible nonparticipating children.Food Consumption/Nutrition/Food Safety,

Identification of Gastroenteric Viruses by Electron Microscopy Using Higher Order Spectral Features

Background: Many paediatric illnesses are caused by viral agents, for example, acute gastroenteritis. Electron microscopy can provide images of viral particles and can be used to identify the agents. Objectives: The use of electron microscopy as a diagnostic tool is limited by the need for high level of expertise in interpreting these images and the time required. A semi-automated method is proposed in this paper. Study design: The method is based on bispectal features that capture contour and texture information while providing robustness to shift, rotation, changes in size and noise. The magnification or true size of the viral particles need not be known precisely, but if available can be used additionally for improved classification. Viral particles from one or more images are segmented and analyzed to verify whether they belong to a particular class (such as Adenovirus, Rotavirus, etc.) or not. Two experiments were conducted—depending on the populations from which virus particle images were collected for training and testing, respectively. In the first, disjoint subsets from a pooled population of virus particles obtained from several images were used. In the second, separate populations from separate images were used. The performance of the method on viruses of similar size was separately evaluated using Astrovirus, HAV and Poliovirus. A Gaussian Mixture Model was used for the probability density of the features. A threshold on the log-likelihood is varied to study false alarm and false rejection trade-off. Features from many particles and/or likelihoods from independent tests are averaged to yield better performance. Results: An equal error rate (EER) of 2% is obtained for verification of Rotavirus (tested against three other viruses) when features from 15 viral particle images are averaged. It drops further to less than 0.2% when scores from two tests are averaged to make a decision. For verification of Astrovirus (tested against two others of the same size) the EER was less than 2% when 20 particles and two tests were used. Conclusion: Bispectral features and Gaussian mixture modelling of their probability density are shown to be effective in identifying viruses from electron microscope images. With the use of digital imaging in electron microscopes, this method can be fully automated

Crashworthiness assessment considering the dynamic damage and failure of a dual phase automotive steel

Analyzing crash worthiness of the automotive parts has been posing a great challenge in the sheet metal and automotive industry since several decades. The present contribution will focus on one of the most urging challenges of the crash worthiness simulations, namely, an enhanced constitutive formulation to predict the failure and cracking of structural parts made from high strength steel sheets under impact. A hybrid extended Modified Bai Wierzbicki damage plasticity model is devised to this end. The material model calibrated using the experimental data covering high strain rate deformation, damage and failure successfully predicted the instability and subsequent response of the crash box under impact. Simulation results provide the deformation shape and deformation energy in order to predict and evaluate the vehicle crashworthiness. The simulations further helped in discovering the irrefutable impact of strain rate and stress state on the impact response of the auto-body structure. The strain rate is found to adequately affect the energy absorption capacity of the crash box structure both in terms of impact load and fold formation whereas the complex stress state has a direct association to the development of instability within the structure and early damage appearance within the folds

Magnetic relaxation in hard type-II superconductors

Magnetic relaxation in a type-II superconductor is simulated for a range of temperatures (T) in a simple model of 2D Josephson junction array (JJA) with finite screening. The high-T phase, that is characterised by a single time scale \tau_{\alpha}, crosses over to an intermediate phase at a lower temperature T_{cr} wherein a second time scale \tau_{\beta}<<\tau_{\alpha} emerges. The relaxation in the time window set by \tau_{\beta} follows power law which is attributed to self-organization of the magnetic flux during relaxation. Consequently, for T<T_{cr}, a transition from super-critical (current density J>J_{c}) to sub-critical (J<J_{c}) state separated by an intermediate state with frozen dynamics is observed. Both \tau_{\alpha} and \tau_{\beta} diverges at T_{sc}<T_{cr}, marking the transition into a state with true persistent current.Comment: 7 Pages (in Europhys format, .sty included), 5 Figures. To appear in Europhysics Letter

Trade Compatibility Between India And Asean Countries

The post WTO world trading system is witnessing proliferation of large number of Regional Trade Agreements (RTAs). The slow pace of multilateral negotiations and lack of consensus among members on major trade issues is undermining the role of WTO and hastening the regionalism process. Realising the importance of East Asia in the emerging global economic order, India signed a FTA with ASEAN which will come in to force from 1st January 2010. For any Regional Trade Agreement (RTA) to be successful, it is imperative on partner countries to have favourable trade structure between them. In this context, the paper looked in to the trade structure of India and ASEAN countries to identify complementary sectors and product groups for enhanced trade cooperation. Trade indices such as Trade Intensity Index (TII) and Revealed Comparative Index (RCA) are constructed at product group, HS-2 and HS-4 levels to get trade complementarity and Similarity. From the analysis it is revealed that there are complementary sectors and products available between India and ASEAN for greater cooperation.Regional Trade Agreement, Revealed Comparative Advantage, India, ASEAN