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The majority of native starch is used in the food sector and in the paper industry. Only a small amount is used in polymer engineering. One reason for the reluctance of the plastics processing industry to use starch as a filling material in polymer blends is the unsatisfactory mechanical behavior of starch when combined with thermoplastics. Another reason is the hydrophilicity of starch. In order to make these materials capable of competing, an amelioration of the mechanical properties is compulsory. By means of modifying the native starch and optimizing the compounding process, it is possible to improve the performance of starch blends, and, thus, increase the number of application areas of these materials. For this reason, native starch was modified with a cross-linking agent using a laboratory mixer. Subsequently, the modified starch and poly(lactic acid) were compounded using a co-rotating twin screw extruder. Cross-linking of the native starch in the laboratory mixer resulted in an increase in the mechanical strength of the starch blends. In addition, the blends with cross-linked starch displayed lower moisture absorption levels than blends with native starch as a filling material.

Background/Objectives:: Given the availability of large longitudinal data sets on human height and weight, different modelling approaches are at hand to access quantities of interest relating to important diagnostic aims. Subjects/Methods:: Statistical modelling frameworks for longitudinal data on human height and weight have to consider the issues of individual heterogeneity and time dependence to provide an accurate statistical characterisation. Further, missing values inevitably occurring within longitudinal data sets have to be addressed adequately to allow for valid inference. The Bayesian framework is illustrated to facilitate stringent comparison of available non-nested model frameworks addressing these issues using simulated and empirical data sets. Results:: Comparing random-effects and fixed-effects modelling approaches with the Preece–Baines (PB) model reveals that, for simulated data, the Bayesian approach towards model comparison is effective in discriminating between different model specifications. With regard to analysis of 14 longitudinal data sets, the implicit trade-off between model fit, that is, description of the data, and a parsimonious parameterisation favouring prediction is often best addressed via the PB model. Conclusions:: The Bayesian approach is illustrated to allow for effective comparison in case model specifications for longitudinal data are not linked directly via parametric restrictions.

Background/Objectives:: Recent evidence suggests clustering of human body height. We want to assess the consequences of connectedness in a spatial network on height clustering in an artificial society. Subjects/Methods:: We used an agent-based computer modelling technique (Monte Carlo simulation) and compared simulated height in a spatial network with characteristics of the observed geographic height distribution of three historic cohorts of Swiss military conscripts (conscripted in 1884–1891; 1908–1910; and 2004–2009). Results:: Conscript height shows several characteristic features: (1) height distributions are overdispersed. (2) Conscripts from districts with direct inter-district road connections tend to be similar in height. (3) Clusters of tall and clusters of short stature districts vary over time. Autocorrelations in height between late 19th and early 21st century districts are low. (4) Mean district height depends on the number of connecting roads and on the number of conscripts per district. Using Monte Carlo simulation, we were able to generate these natural characteristics in an artificial society. Already 5% height information from directly connected districts is sufficient to simulate the characteristics of natural height distribution. Very similar observations in regular rectangular networks indicate that the characteristics of Swiss conscript height distributions do not so much result from the particular Swiss geography but rather appear to be general features of spatial networks. Conclusions:: Spatial connectedness can affect height clustering in an artificial society, similar to that seen in natural cohorts of military conscripts, and strengthen the concept of connectedness being involved in the regulation of human height.

Summary Body height is associated with environmental conditions. It has been suggested that under poor conditions when inequality within a population increases, also the variability in height tends to increase. We studied the association of body height, within-country variability in height and geographic and historic origin in 767 growth studies carried out in 80 countries, published between 1794 and 2013, with data on N = 78,184 infants age 2 years, and N = 2,130,729 juveniles age 7 years. The studies represent almost the whole spectrum of economic diversity in human societies since the end-18th century. 207 studies contained data for both infants and juveniles with 50,819 subjects (age 2), and 123,078 subjects (age 7). Multiple linear regressions showed significant interactions between height, sex, historic year of the study, geographic origin, and within-study standard deviation for height with multiple R-squared = 0.527, p < 0.001, at age 2, and multiple R-squared = 0.436, p < 0.001, at age 7. Yet, the two age groups differed in respect to within-study standard deviation for height. We found a significant association between body height and within-study standard deviation for height only at age 2: tall infant populations are less variable in height (r = –0.27, p < 0.01). There was no such association in children aged 7 years. Tall children from affluent and short children from less affluent countries do not differ in the variability of body height. The data suggest that the ‘environmental adversity’ hypothesis for variation in growth: small mean values for height go along with large standard deviations for height, does not apply for children at age 7.

Background/Objectives:: Besides large efforts regarding field work, provision of valid databases requires statistical and informational infrastructure to enable long-term access to longitudinal data sets on height, weight and related issues. Subjects/Methods:: To foster use of longitudinal data sets within the scientific community, provision of valid databases has to address data-protection regulations. It is, therefore, of major importance to hinder identifiability of individuals from publicly available databases. To reach this goal, one possible strategy is to provide a synthetic database to the public allowing for pretesting strategies for data analysis. The synthetic databases can be established using multiple imputation tools. Given the approval of the strategy, verification is based on the original data. Results:: Multiple imputation by chained equations is illustrated to facilitate provision of synthetic databases as it allows for capturing a wide range of statistical interdependencies. Also missing values, typically occurring within longitudinal databases for reasons of item non-response, can be addressed via multiple imputation when providing databases. Conclusions:: The provision of synthetic databases using multiple imputation techniques is one possible strategy to ensure data protection, increase visibility of longitudinal databases and enhance the analytical potential.

A partly resistive superconducting quantum interference device, or, RSQUID, is a device utilizing the nonstationary Josephson effect. The resistive part of the device makes it possible to apply a voltage to the Josephson junctions and, in this way, to convert it into frequency. The transconductance ratio of this conversion is defined by the physical constants: 1/ø0 = 2e/h (ø0 is the flux quantum). Five different types of thin-film RSQUIDs are described in this paper. They are: an rf RSQUID with an rf pump and one Josephson junction, a dc RSQUID with dc bias and two Josephson junctions, and three topologically different double RSQUIDs with an rf pump, two Josephson junctions and two quantization loops. All five types were successfully fabricated. The resistive part of all devices was an S-N-S sandwich with Nb as the superconductor (S) and Cu as the normal metal (N). Such a design of the resistive part sets its resistance on the order of a few tens of µO.

Correction to: European Journal of Clinical Nutrition advance online publication 6 April 2016; doi:10.1038/ejcn.2016.45 Since the publication of this article, the authors have noticed an error in the author list. The author Kaspar Staub of the Institute of Evolutionary Medicine (IEM), University of Zurich, Switzerland, has since been added.

Abstract: We introduce an all thin film dc resistive SQUID (dc RSQUID) that works from 4.2K down to the mK range. It consists of conventional Nb/A1O/Nb tunnel junctions and an integrated Ag film resistor. With a special planar design for the resistor we achieve the necassary low value of resistance of some 10−5Ω. The resistor remains normal conducting in the whole temperature range investigated, despite the proximity effect. The characteristic parameters of the RSQUID show negligible tmeperature dependence. An integrated RSQUID could revive noise thermometry in the mK range because of its higher signal to noise ratio and the advantages of simple read out electronics and easy handling compared to the bulk devices used up till now.