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Panel data are collected over several time periods for the same units and hence allow for modelling both latent heterogeneity and dynamics. Since in a dynamic setup, the dependent variable also appears as an explanatory variable in later periods, missing values lead to substantial loss of information and the possibility of inefficient estimation. For linear dynamic panel models with fixed or random effects, we suggest a Bayesian approach to deal with missing values. The Gibbs sampling scheme providing a sample from the posterior distribution is thereby augmented by draws from the full conditional distribution of the missing values. While the full conditional distribution for missing values in the dependent variable is implied by the model setup, we incorporate a flexible non‐parametric approximation to the full conditional posterior distribution of missing values in the explaining variables. Also, we provide accurate non‐nested model comparison in terms of the marginal likelihood from the resulting hybrid Gibbs sampling output. The properties and possible efficiency gains of the suggested approach are illustrated by means of a simulation study and an empirical application using a macroeconomic panel data set.

An IC-ECL with different waveguide concepts and a MEMS device as tuning element for high acquisition rates is presented. Characterization results and use for detection of trace gases in the MIR region will be shown.

IC-ECLs with straight and curved waveguide concepts are analyzed and presented. The results of the characterization and the use for the detection of trace gases with acquisition rates above 1 kHz are shown.

A policy network approach has been developed to assess participatory policy processes in Ghana, Senegal, and Uganda. Theoretically, political influence measures correspond to two different influence mechanisms: vote-buying and informational lobbying. For each mechanism, separate measures were defined and empirically derived from corresponding policy networks. Exponential random graph models were used to assess the network-generating process, which allows for analysis of the robustness of the derived influence measures and the determinants of network structure. The results imply that participatory policy processes are dominated by donor and research organizations, while farm interests and civil society organizations have only a negligible influence. The design of stakeholder systems appears to be difficult since the observed network structures are mainly determined by relational factors that result from organizations’ social networking activities or other organizational attributes, such as reputation power, which cannot be easily controlled. Institutional factors such as membership in committees have only a minor impact.

The detection and identification of molecular gases are of high relevance in many applications within healthcare, production monitoring and safety as well as environmental monitoring. One of the major difficulties of trace gas analysis is due to the bulky and expensive systems, what excludes both mobile and handheld use. For this purpose we present our new system based on the Quartz Enhanced PhotoAcoustic Spectroscopy (QEPAS), which can provide the required properties for gas analysis. We have developed a compact detection unit where DFB laser, collimation optics and QTF are integrated in a 14-pin butterfly housing. Therefore an optimization of the DFB laser chips will be presented too. The results show, that the laser diodes not only provide excellent performance, but also allow a detection limit for the greenhouse gas methane and carbon dioxide in the ppm range.

(1) Background: We present a new statistical approach labeled as “St. Nicolas House Analysis” (SNHA) for detecting and visualizing extensive interactions among variables. (2) Method: We rank absolute bivariate correlation coefficients in descending order according to magnitude and create hierarchic “association chains” defined by sequences where reversing start and end point does not alter the ordering of elements. Association chains are used to characterize dependence structures of interacting variables by a graph. (3) Results: SNHA depicts association chains in highly, but also in weakly correlated data, and is robust towards spurious accidental associations. Overlapping association chains can be visualized as network graphs. Between independent variables significantly fewer associations are detected compared to standard correlation or linear model-based approaches. (4) Conclusion: We propose reversible association chains as a principle to detect dependencies among variables. The proposed method can be conceptualized as a non-parametric statistical method. It is especially suited for secondary data analysis as only aggregate information such as correlations matrices are required. The analysis provides an initial approach for clarifying potential associations that may be subject to subsequent hypothesis testing.

The rapid detection of trace gases is of great relevance for various spectroscopy applications. In this regard, the technology of external cavity diode lasers (ECDLs) has firmly established itself due to its excellent properties. Outside of the laboratory environment, however, these still have some restrictions, especially with regard to high acquisition rates for sensitive spectroscopy applications and mode-hop-free tuning. In this article, we present our innovative GaSb-based ECDL concept, in which a resonantly driven microelectromechanical system actuator is used. With this, a defined frequency range can be tuned extremely fast and without mode hops. Results of the characterization and its use for the rapid detection of trace gases are presented.

An optimized D-DFB design is presented, which guarantees the best possible performance in the range from 1.9 µm to 4.5 µm. Results for the performance and its suitability for detecting trace gases are shown.

An MEMS based ECDL design with optimized curved gain chip for the MIR region is presented. Results of the characterization and its use for the rapid detection of trace gases are shown.

Optimized DFB lasers are presented. Results for the performance and its suitability for detecting trace gases are shown. We present our new QEPAS compact detection unit where everything is integrated into 14-pin butterfly housing.

GaSb based types of diode lasers may cover the spectral regime from below 1.8 μm up to 5 μm. For the wavelength regime of 1.8 μm to 2.5 μm InGaAsSb/GaSb MQW material is used. For 2.5 μm to 3.4 μm InAlGaAsSb/GaSb MQW material is used. For above 3μm, an ICL type of design is required. We realized a growth campaign of 10 GaSb based wavers for covering the wavelength regime from 1.9μm to 3μm. We report on the test, performance and applications results in molecular gas sensing of both, gain chips within an external cavity laser as well as on digital DFB lasers.

OBJECTIVES Human growth and final height are influenced by many factors such as genetics, nutrition, living conditions, socioeconomic background and, as recently proposed, by social peer groups and the community. In this paper, we aim to evaluate the extent to which spatial proximity, acting as a proxy for the social community, causes height clustering in low and middle income countries. MATERIAL AND METHODS We analyzed data from the study "Young Lives-Measuring Child Poverty and Health", a study performed in four low and middle income countries (Ethiopia, India, Peru and Vietnam) to describe the health situation of children. We used linear mixed effects models with different random effect structures to analyze the influence of the community on clustering of height in boys and girls. RESULTS In all analyzed low and middle income countries, linear mixed effects with hierarchical structures with communities nested within regions provide a better fit than the basic models neglecting community-based clustering (p

The investigation of learning processes by assessing students’ experience along with objective characteristics within a classroom context has a long tradition in empirical learning process research (e.g. Sembill, 1984 et passim; Wild & Krapp, 1996). However, most of the existing studies confine themselves to psychological variables that seem to be too narrowly considered, as there is theoretical and empirical evidence proving the involvement of somatic and psychological processes in learning and in stress reactions. Furthermore there is a lack of studies that investigate situation-related experience (states) as an outcome of interactions between relatively stable characteristics (traits) and continuously changing “objective” context conditions. Against this background, we will present an approach for cross-classified multilevel longitudinal modelling of person-situation interactions in naturalistic educational settings. We illustrated our model with the example of students’ stress experience referring to empirical data that we measured within a multidisciplinary research project (pedagogy, psychology, adolescent medicine). 53 students at a public German vocational school were investigated during 9 lessons. There are up to 38 state measurements per person, resulting in 2,014 measurements in total. Taking into account that states are nested within persons and within situations we applied a cross-classified multilevel model to analyse effects on students’ stress experience. The analysis shows significant person-situation interactions between academic self-concept and classroom demands and between baseline cortisol concentration and classroom demands: the relation between classroom demands and stress experience depends on relatively stable person-related characteristics. A deeper knowledge about the complex interrelations between traits, states, and continuously changing context conditions seems to be essential for a more holistic understanding of learning at school and for the identification of crucial aspects for an evidence-based design and implementation of teaching and learning arrangements. published

HITRAN promises better gas detection possibilities in the MIR wavelength regime than the NIR or the visible region because of the higher absorbencies. These promises are tested with different lasers on TDLAS and QEPAS applications.

The German National Educational Panel Study (NEPS) was set up to provide an empirical basis for longitudinal analyses of individuals’ educational careers and competencies and how they unfold over the life course in relation to family, formal educational institutions, and private life. Educational developments and decisions over the life span are being tracked in six starting cohorts as a foundation for characterizing and analyzing educational processes. These six starting cohorts include newborns, Kindergarten children, secondary school children (5th and 9th grade), first-year undergraduate students, and adults. Because access to the target population in several starting cohorts was gained via educational institutions such as Kindergartens and schools, multistage sampling approaches were implemented that reflect the clustered structure of the target populations. Samples in individual contexts, such as those in the adult and newborn cohorts, were established via register-based stratified cluster approaches. This chapter briefly reviews the designs of the implemented sampling strategies for each established starting cohort and provides information on the levels of attrition in the panel development.

The commercially available semiconductor lasers for the mid-infrared (MIR) region often do not reach the desired performance and represent a limitation for gas sensor technology. Here we present our digital distributed feedback filter (D-DFB) laser diodes based on GaSb gain material, which have been optimized in terms of facet reflectivity, chip length, and output power. These diodes now cover the wavelength range from 1900 nm up to 4500 nm and show excellent quality regarding their spectral characteristics. Results for the performance of the D-DFB laser design and its suitability for the detection of trace gases are shown in this publication.

Due to their indeterminacies, static and dynamic factor models require identifying assumptions to guarantee uniqueness of the parameter estimator. The indeterminacy of the parameter estimator with respect to an orthogonal transformation is known as the rotation problem. The typical strategy in Bayesian factor analysis to solve the rotation problem is to introduce ex-ante constraints on certain model parameters via degenerate and truncated prior distributions. This strategy, however, results in posterior distributions whose shapes depend on the ordering of the variables in the data set. We propose an alternative approach where the rotation problem is solved ex-post using Procrustean postprocessing. The resulting order invariance of the posterior estimator is illustrated in a simulation study and an empirical application using an established data set containing 120 macroeconomic time series. Favorable properties of the ex-post approach with respect to convergence, statistical and numerical accuracy are revealed.

Large-scale surveys typically exhibit data structures characterized by rich mutual dependencies between surveyed variables and individual-specific skip patterns. Despite high efforts in fieldwork and questionnaire design, missing values inevitably occur. One approach for handling missing values is to provide multiply imputed data sets, thus enhancing the analytical potential of the surveyed data. To preserve possible nonlinear relationships among variables and incorporate skip patterns that make the full conditional distributions individual specific, we adapt a full conditional multiple imputation approach based on sequential classification and regression trees. Individual-specific skip patterns and constraints are handled within imputation in a way ensuring the consistency of the sequence of full conditional distributions. The suggested approach is illustrated in the context of income imputation in the adult cohort of the National Educational Panel Study.

Objectives: To reanalyze the between-population variance in height, weight, and body mass index (BMI), and to provide a globally applicable technique for generating synthetic growth reference charts. Methods: Using a baseline set of 196 female and 197 male growth studies published since 1831, common factors of height, weight, and BMI are extracted via Principal Components separately for height, weight, and BMI. Combining information from single growth studies and the common factors using in principle a Bayesian rationale allows for provision of completed reference charts. Results: The suggested approach can be used for generating synthetic growth reference charts with LMS values for height, weight, and BMI, from birth to maturity, from any limited set of height and weight measurements of a given population. Conclusion: Generating synthetic growth reference charts by incorporating information from a large set of reference growth studies seems suitable for populations with no autochthonous references at hand yet. © 2015 Wiley Periodicals, Inc.

We test the hypothesis that differences in social status between groups of people within a population may induce variation in insulin-like growth factor-1(IGF-1) levels and, by extension, growth in height. This is called the community effect in height hypothesis. The relationship between IGF-1, assessed via finger-prick dried blood spot, and elite level sport competition outcomes were analysed for a sample of 116 undergraduate men and women. There was a statistically significant difference between winners and losers of a competition. Winners, as a group, had higher average pre-game and post-game IGF-1 levels than losers. We proposed this type of difference as a proxy for social dominance. We found no evidence that winners increased in IGF-1 levels over losers or that members of the same team were more similar in IGF-1 levels than they were to players from other teams. These findings provide limited support toward the community effect in height hypothesis. The findings are discussed in relation to the action of the growth hormone/IGF-1 axis as a transducer of multiple bio-social influences into a coherent signal which allows the growing human to adjust and adapt to local ecological conditions.

This chapter presents an empirical approach towards analyzing the determinants of elite communication networks. Such an analysis allows for the evaluation of real-world participatory policy processes in terms of their informing and distorting nature. A case in point is the participatory policy process leading to the launch of the Comprehensive Africa Agriculture Development Programme (CAADP) in Malawi. Network data were collected via face-to-face interviews with Malawi’s political elite. In this approach, we use an extended binary regression framework, which can deal with missing values inevitably occurring within survey data. In fact, model parameters are estimated using an adaptation of the Bayesian estimation scheme for binary probit models based on the Markov Chain Monte Carlo (MCMC) methodology. Empirical results suggest that (i) homophily in policy interests is not a significant basis for tie choice, (ii) knowledge is an important but not leading determinant of communication, and (iii) the structural embeddedness of organizations within the network mainly determines the formation of ties. Overall, we summarize that, although the policy network formation underlying participatory structures in Malawi clearly discriminates between types of non-governmental organizations, it is not distorted in favor of specific social groups.

FPGA-Based locking and high power tunable diode laser (1.1W, 1530nm), suitable for locking to acetylene hyperfine structure, are presented. The system allows locking to the R5 state of the hyperfine structure with excellent long term stability.

Narrow linewidth tunable diode lasers are an important tool for spectroscopic instrumentation. Conventional external cavity diode lasers are designed as laboratory instrument and do not allow hand-held operation for portable instruments. A new miniaturized type of tunable external cavity tunable diode laser will be presented. The presentation will focus on requirements on the assembly technology of micro-optic components as well as on the physical properties of such devices. Examples for the realization of this new technology will be given in the NIR for Alkaline Spectroscopy as well as in the MIR at 1908nm.

A 1530 nm high power tunable diode laser system with FPGA locking to acetylene is presented. The system is locked to the hyperfine structure of the R5 state with excellent long term stability.

The MIR wavelength regime promises better gas detection possibilities than the NIR or the visible region because of the higher absorbencies simulated by HITRAN. In the MIR region are many important absorption lines of significant gases, which are relevant in healthcare, production supervision, and safety and environmental monitoring. One of those gases is methane. CH4 shows significant variations in absorbance with a maximum at 3.3 μm, which results in low detection limits in the range of low ppm. Interband-cascade- and quantum-cascade-based lasers emit at higher wavelengths, where the absorbencies of methane are higher. The comparison is done by analyzing the performance of two spectroscopy applications: tunable diode laser absorption spectroscopy and quartz-enhanced photoacoustic spectroscopy.

Human growth is traditionally envisaged as a target-seeking process regulated by genes, nutrition, health, and the state of an individual’s social and economic environment; it is believed that under optimal physical conditions, an individual will achieve his or her full genetic potential. Using a panel data set on individual height increments, we suggest a statistical modeling approach that characterizes growth as first-order trend stationary and allows for controlling individual growth tempo via observable measures of individual maturity. A Bayesian framework and corresponding Markov-chain Monte Carlo techniques allowing for a conceptually stringent treatment of missing values are adapted for parameter estimation. The model provides evidence for the adjustment of the individual growth rate toward average height of the population. The increase in adult body height during the past 150 y has been explained by the steady improvement of living conditions that are now being considered to have reached an optimum in Western societies. The current investigation questions the notion that the traditional concept in the understanding of this target-seeking process is sufficient. We consider an additional regulator that possibly points at community-based target seeking in growth.

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-18(th) 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.

Recent empirical evidence suggests that reversing current account balances imply costly adjustment processes leading to reduced economic growth. Using large panel data sets to analyze determinants and costs of reversals asks for controls of heterogeneity among countries. This paper contributes a Bayesian analysis, which allows a parsimonious yet flexible handling of country specific heterogeneity via random coefficients. Furthermore, the analysis allows for serially correlated errors in order to capture persistence within the employed macroeconomic data. Bayesian specification tests provide evidence in favor of models incorporating heterogeneity and serial correlation. The results suggest that consideration of serial correlation and heterogeneity is necessary to assess correctly the determinants and costs of reversals. Results are checked for robustness against the underlying reversal definition.

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.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.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.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.

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. 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. 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. The Bayesian approach is illustrated to allow for effective comparison in case model specifications for longitudinal data are not linked directly via parametric restrictions.

SUMMARY The aim of this study was to assess changes in prevalence of overweight and obesity among children born in 1996 and 1990 in Vilnius city. The results were based on comparison of two longitudinal data sets (N = 624 and N = 389) collected from the personal health records of children born in 1996 and 1990 respectively. No statistically significant differences in final height and BMI were established between children born in 1990 and 1996; however, both boys and girls born in 1996 appeared to be higher and heavier at different ages compared to their peers born in 1990. After controlling for tempo, the differences in height between the two cohorts have become insignificant for girls, with exceptions at the age of 3 and 10 years; for boys, the differences between the cohorts have remained significant, however at a slightly lower level. More children born in 1996 tended to be overweight and obese. In six years, the prevalence of overweight in Vilnius children has more than doubled; the prevalence of obesity has increased up to five times in some age groups.

Height and skeletal morphology strongly relate to life style. Parallel to the decrease in physical activity and locomotion, modern people are slimmer in skeletal proportions. In German children and adolescents, elbow breadth and particularly relative pelvic breadth (50th centile of bicristal distance divided by body height) have significantly decreased in recent years. Even more evident than the changes in pelvic morphology are the rapid changes in body height in most modern countries since the end-19th and particularly since the mid-20th century. Modern Japanese mature earlier; the age at take-off (ATO, the age at which the adolescent growth spurt starts) decreases, and they are taller at all ages. Preece-Baines modelling of six national samples of Japanese children and adolescents, surveyed between 1955 and 2000, shows that this gain in height is largely an adolescent trend, whereas height at take-off (HTO) increased by less than 3 cm since 1955; adolescent growth (height gain between ATO and adult age) increased by 6 cm. The effect of globalization on the modern post-war Japanese society ("community effect in height") on adolescent growth is discussed., Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe, 869

This paper analyzes the costs of housing crises in terms of GDP growth and the economic conditions under which crises are particularly costly. Housing crises are often followed by recessions that are longer than other recessions. According to empirical estimates, a housing crisis reduces the GDP growth rate in the following year on average by two percentage points and has still a considerable negative impact in the second year. One important channel through which the effect of housing crises is passed on seems to be the banking sector. In addition, our results suggest that negative wealth effects possibly cause further reductions in GDP.

Aim: National European growth references differ. We aimed to convert (harmonize) currently used charts into a single unified interchangeable LMS format for each European nation. Methods: Nine currently used national European growth references from Belgium (2009), France (1979), Poland (2001), Sweden (2002), Switzerland (1989), the UK (1990), Italy (2006) and Germany (1979 and 1997) were harmonized and compared with the international WHO child growth standards and WHO growth reference data for 5–19 years. Results: European growth charts can be harmonized. The approach appears useful as height, and body mass index (BMI) is inappropriately represented by WHO references. European height references exhibit warping when plotted against the WHO reference. The French appears too short, the other Europeans too tall. Also, the BMI is not appropriately represented by the WHO references. Conclusions: Harmonizing references is a novel, convenient and cost-effective approach for converting historic and/or incomplete local or national growth reference charts into a unified interchangeable LMS format. Harmonizing facilitates producing growth references ‘on demand’, for limited regional purposes, for ethnically, socio-economically or politically defined minorities, but also for matching geographically different groups of children and adolescents for international growth and registry studies.

Government bond spreads increased rapidly during the financial turmoil in the euro area. In general, government bond spreads in the euro area are attributed to solvency and liquidity risks and determinants thereof. This paper proposes the use of latent processes to model the time variation present in the evaluation of these determinants. In contrast to approaches using global measures like the US corporate bond spreads or short-term interest rates to approximate time variation, our model is also flexible enough to deal with the unfolding of the financial crisis. The findings suggest that the expected debt-to-GDP ratio explains a major part of the differences in bond yields in the euro area between 2003 and the unfolding of the financial crises. Coefficients for many determinants increased rapidly during the financial crises. Especially market capitalization gained relative importance in winter 2008/2009.

Growth reference charts are important tools for adequate paediatric decisions.In view of the workload required to construct empirical growth reference charts we debate practicable and less demanding alternatives and took the recent national 2000-2002 Lithuanian growth charts as an example. Two options appeared reasonable: (1) applying international WHO child growth standards and WHO growth reference data for 5-19 years that are recommended for global use; or (2) replacing the costly empirical method of deriving national growth references by more convenient low-cost statistics, e.g. the method of generating synthetic references for the Lithuanian population.We analysed the degree of agreement between the 2000-2002 Lithuanian growth charts, and the international WHO child growth standards and WHO growth reference data for 5-19 years and synthetic references for the Lithuanian population using the Bland-Altman method.Synthetically generated references for the Lithuanian population slightly surpassed the national Lithuanian reference for body height (males +0.3 (SD 0.9) cm; females +0.2 (SD 0.6) cm) particularly at young age, which may be regarded clinically irrelevant. WHO international child growth standards and the WHO growth reference data for 5-19 years, however, failed to match the Lithuanian references as they underestimated mean height in boys by -2.8 (SD 1.4) cm and in girls by -2.9 (SD 1.1) cm, with extremely discrepant estimates of more than -6 cm occurring in several adolescent cohorts.The analysis revitalizes the debate on clinically relevant and at the same time practicable but less demanding alternatives for constructing growth reference charts, and for economic reasons, strongly suggests replacing the traditional empirical methods by synthetic growth references.

The analysis of sharp and persistent reductions of current account deficits, which can be characterized as the transition from an unsustainable to a more sustainable level of current account balance, relies often on ad hoc criteria for identification of reversal episodes. Within this paper, an empirical framework in terms of a regime switching approach is presented allowing simultaneous identification of current account reversal episodes and their determinants. Additionally, this approach is extended towards analysis of the impact of a reversal on the path of economic growth. Empirical investigation of a panel containing developing countries suggests a different timing of reversals compared to timing delivered by ad hoc criteria. However, several determinants of reversals discussed in the literature remain valid. Our estimates of costs implied by the occurrence of a current account reversal amount to a severe reduction of economic growth, where output costs are found to vary largely across countries.

The wavelength, λ, range of 1.8 μm≤λ≤3.5 μm contains strong spectral absorption lines of many gases used in health, industry, safety, and medicine and whose sensitive and quantitative detection is desirable. However, the performance of InP diode lasers markedly deteriorates beyond λ∼2 μm. In this paper we present new results on developing tunable high power single mode laser diodes based on the GaSb material system with emission in the wavelength range of 1.8 μm≤λ≤2.2 μm.

Background: Human populations differ in height. Recent evidence suggests that social networks play an important role in the regulation of adolescent growth and adult height. We further investigated the effect of physical connectedness on height. Material and methods: We considered Switzerland as a geographic network with 169 nodes (district capitals) and 335 edges (connecting roads) and studied effects of connectedness on height in Swiss conscript from 1884-1891, 1908-1910, and 2004-2009. We also created exponential-family random graph models to separate possible unspecific effects of geographic vicinity. Results: In 1884-1891, in 1908-1910, and in 2004-2009, 1st, 2nd and 3rd order neighboring districts significantly correlate in height (p

Das Nationale Bildungspanel (NEPS) untersucht Bildungsprozesse und Kompetenzentwicklungen uber den gesamten Lebenslauf. Als Infrastrukturangebot fur alle an Bildungsfragen interessierten Disziplinen werden in dieser Studie mit verschiedenen reprasentativen Stichproben reichhaltige Daten zu diesen Verlaufen erhoben und der Wissenschaftsgemeinschaft zur Verfugung gestellt. Dabei ist es von zentraler Bedeutung, die in den verschiedenen Lebensphasen relevanten Kontexte zu erheben und eine Analyse der Auswirkungen auf die weiteren Bildungswege und den Erwerb von Kompetenzen zu ermoglichen. Im Nationalen Bildungspanel werden nicht nur innovative Konzepte zur Erfassung der verschiedensten formalen und informellen Lerngelegenheiten entwickelt und Daten zu den von fruher Kindheit bis in das hohe Erwachsenenalter jeweils relevanten Kontexten erhoben, auch zielt das Stichprobendesign darauf ab, die Analyse von Kontexteffekten zu verbessern.

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.