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In this study, we introduce a portable low-cost device for in situ gas emission measurement from focused point sources of CO2, such as mofettes. We assess the individual sensors' precision with calibration experiments and perform an independent verification of the system's ability to measure gas flow rates in the range of liters per second. The results from one week of continuous CO2 flow observation from a wet mofette at the Starzach site is presented and correlated with the ambient meteorological dynamics. In the observed period, the gas flow rate of the examined mofette exhibits a dominant cycle of around four seconds that is linked to the gas rising upwards through a water column. We find the examined mofette to have a daily emission of 465 kg ±16 %. Furthermore, two events were observed that increased the flow rate abruptly by around 25 % within only a few minutes and a decaying period of 24 hours. These types of events were previously observed by others at the same site but dismissed as measurement errors. We discuss these events as a hydrogeological phenomenon similar to cold-water geyser eruptions. For meteorological events like the passages of high pressure fronts with steep changes in atmospheric pressure, we do not see a significant correlation between atmospheric parameters and the rate of gas exhalation in our one-week time frame, suggesting that on short timescales the atmospheric pumping effect plays a minor role for wet mofettes at the Starzach site. [ABSTRACT FROM AUTHOR]

Accurate precipitation data are essential for assessing the water balance of ecosystems. Methods for point precipitation determination are influenced by wind, precipitation type and intensity and/or technical issues. High-precision weighable lysimeters provide precipitation measurements at ground level that are less affected by wind disturbances and are assumed to be relatively close to actual precipitation. The problem in previous studies was that the biases in precipitation data introduced by different precipitation measurement methods were not comprehensively compared with and quantified on the basis of those obtained by lysimeters in different regions in Germany. The aim was to quantify measurement errors in standard precipitation gauges as compared to the lysimeter reference and to analyze the effect of precipitation correction algorithms on the gauge data quality. Both correction methods rely on empirical constants to account for known external influences on the measurements, following a generic and a site-specific approach. Reference precipitation data were obtained from high-precision weighable lysimeters of the TERrestrial ENvironmental Observatories (TERENO)-SOILCan lysimeter network. Gauge types included tipping bucket gauges (TBs), weighable gauges (WGs), acoustic sensors (ASs) and optical laser disdrometers (LDs). From 2015-2018, data were collected at three locations in Germany, and 1 h aggregated values for precipitation above a threshold of 0.1 mm h -1 were compared. The results show that all investigated measurement methods underestimated the precipitation amounts relative to the lysimeter references for long-term precipitation totals with catch ratios (CRs) of between 33 %–92 %. Data from ASs had overall biases of -0.25 to -0.07 mm h -1 , while data from WGs and LDs showed the lowest measurement bias (-0.14 to -0.06 mm h -1 and -0.01 to -0.02 mm h -1). Two TBs showed systematic deviations with biases of -0.69 to -0.61 mm h -1 , while other TBs were in the previously reported range with biases of -0.2 mm h -1. The site-specific and generic correction schemes reduced the hourly measurement bias by 0.13 and 0.08 mm h -1 for the TBs and by 0.09 and 0.07 mm h -1 for the WGs and increased long-term CRs by 14 % and 9 % and by 10 % and 11 %, respectively. It could be shown that the lysimeter reference operated with minor uncertainties in long-term measurements under different site and weather conditions. The results indicate that considerable precipitation measurement errors can occur even at well-maintained and professionally operated stations equipped with standard precipitation gauges. This generally leads to an underestimation of the actual precipitation amounts. The results suggest that the application of relatively simple correction schemes, manual or automated data quality checks, instrument calibrations, and/or an adequate choice of observation period can help improve the data quality of gauge-based measurements for water balance calculations, ecosystem modeling, water management, assessment of agricultural irrigation needs, or radar-based precipitation analyses. [ABSTRACT FROM AUTHOR]

The Kamioka Gravitational wave detector (KAGRA) cryogenic gravitational-wave observatory has commenced joint observations with the worldwide gravitational wave detector network. Precise calibration of the detector response is essential for accurately estimating parameters of gravitational wave sources. A photon calibrator is a crucial calibration tool used in laser interferometer gravitational-wave observatory, Virgo, and KAGRA, and it was utilized in joint observation 3 with GEO600 in Germany in April 2020. In this paper, KAGRA implemented three key enhancements: a high-power laser, a power stabilization system, and remote beam position control. KAGRA employs a 20 W laser divided into two beams that are injected onto the mirror surface. By utilizing a high-power laser, the response of the detector at kHz frequencies can be calibrated. To independently control the power of each laser beam, an optical follower servo was installed for power stabilization. The optical path of the photon calibrator's beam positions was controlled using pico-motors, allowing for the characterization of the detector's rotation response. Additionally, a telephoto camera and quadrant photodetectors were installed to monitor beam positions, and beam position control was implemented to optimize the mirror response. In this paper, we discuss the statistical errors associated with the measurement of relative power noise. We also address systematic errors related to the power calibration model of the photon calibrator and the simulation of elastic deformation effects using finite element analysis. Ultimately, we have successfully reduced the total systematic error from the photon calibrator to 2.0%. [ABSTRACT FROM AUTHOR]

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The UCLA Loneliness Scale (ULS-20) and its short version (ULS-8) are widely used to measure loneliness. However, the question remains whether or not previous studies using the scale to measure loneliness are measuring the construct equally across countries. The present study examined the measurement invariance (MI) of both scales in Germany, Indonesia, and the United States (N = 2350). The one-, two-, and three-factor structure of the ULS-20 did not meet the model fit cut-off criteria in the total sample. The ULS-8 met the model fit cut-off criteria and has configural, but not metric invariance because two items unrelated to social isolation were not MI. The final six items (ULS-6) exclusively related to social isolation had complete MI. Participants from the United States scored highest in the ULS-6, followed by participants from Germany and then Indonesia. We conclude that the ULS-6 is an appropriate measure for cross-cultural studies on loneliness. [ABSTRACT FROM AUTHOR]

The present study aimed to explore children's and adolescents' profiles of reactive and proactive aggression and the stability of those profiles over a six-month period using latent profile analysis (LPA) and latent transition analysis (LTA). Data were collected at two measurement points from a sample of N = 1468 children and adolescents aged from 9 to 18 years. Results of LPA revealed three distinct profiles, labeled as "Severe Reactively and Proactively Aggressive (S-RA-PA)", "Highly Reactively and Proactively Aggressive" (H-RA-PA), and "Moderately Low Reactively and Proactively Aggressive" (M-RA-PA). All profiles appeared to be relatively stable over six months, supporting their within-sample consistency. The most stable and largest profile was the "M-RA-PA" profile, while the least stable and smallest profile was the "S-RA-PA" profile. However, there was also some within-person variability in children's and adolescents' profile membership because almost 40–50% of the participants of the "S-RA-PA" and "H-RA-PA" profiles transitioned to another profile across six months. In contrast, more than 90% of the participants of the "M-RA-PA" profile remained in their profile. These results provide a dynamic picture of children's and adolescents' development of reactive and proactive aggression and bear several implications from a short longitudinal person-oriented perspective. [ABSTRACT FROM AUTHOR]

Major depression is a severe mental disorder that is associated with strongly increased mortality. The quantification of its prevalence on regional levels represents an important indicator for public health reporting. In addition to that, it marks a crucial basis for further explorative studies regarding environmental determinants of the condition. However, assessing the distribution of major depression in the population is challenging. The topic is highly sensitive, and national statistical institutions rarely have administrative records on this matter. Published prevalence figures as well as available auxiliary data are typically derived from survey estimates. These are often subject to high uncertainty due to large sampling variances and do not allow for sound regional analysis. We propose a new area-level Poisson mixed model that accounts for measurement errors in auxiliary data to close this gap. We derive the empirical best predictor under the model and present a parametric bootstrap estimator for the mean squared error. A method of moments algorithm for consistent model parameter estimation is developed. Simulation experiments are conducted to show the effectiveness of the approach. The methodology is applied to estimate the major depression prevalence in Germany on regional levels crossed by sex and age groups. [ABSTRACT FROM AUTHOR]

Assessing regional population compositions is an important task in many research fields. Small area estimation with generalized linear mixed models marks a powerful tool for this purpose. However, the method has limitations in practice. When the data are subject to measurement errors, small area models produce inefficient or biased results since they cannot account for data uncertainty. This is particularly problematic for composition prediction, since generalized linear mixed models often rely on approximate likelihood inference. Obtained predictions are not reliable. We propose a robust multivariate Fay–Herriot model to solve these issues. It combines compositional data analysis with robust optimization theory. The nonlinear estimation of compositions is restated as a linear problem through isometric logratio transformations. Robust model parameter estimation is performed via penalized maximum likelihood. A robust best predictor is derived. Simulations are conducted to demonstrate the effectiveness of the approach. An application to alcohol consumption in Germany is provided. [ABSTRACT FROM AUTHOR]

[Display omitted] Interactions between droplets are of fundamental importance for understanding phenomena involving droplet collision and coalescence that determine multiphase flow behavior. The quantitative understanding of these interactions is essential for the manipulation and control of emulsions or complex fluids. The existing methods for interaction force determination are typically based on expensive mechanical probes and fine distance control. Therefore, further development of new techniques for interaction force determination is expected to be beneficial for research on surface force. In this study, droplet deformation during the interaction between two droplets was captured and analyzed to determine the interaction force. The approach speed of the two droplets was controlled by the injection rate of the fluid. The dynamic interaction force between two tetradecane droplets in various aqueous solutions was determined using the newly developed method, and the effects of two-phase physical properties and operating conditions on the measurement errors were investigated. The droplet profile deformation was first applied as a probe to detect the interaction force. The measurement results were in good agreement with those obtained using the precise weighing sensor of a commercial interfacial tensiometer (K100, Kruss, Germany). The newly developed method was reliable, simple, and did not require the use of expensive devices. Furthermore, droplet deformability was found to be the key parameter in determining the total interaction force between the droplets. [ABSTRACT FROM AUTHOR]

Background and Aims: Cancer treatments often require intensive use of healthcare services and limit patients' ability to work, potentially causing them to become financially vulnerable. The present study is the first attempt to measure, on the German national level, the magnitude of absolute income loss after a cancer diagnosis. Methods: This study analyzes data from the Socio‐Economic Panel (SOEP) survey, one of the largest and most comprehensive household surveys in Germany, consisting of approximately 20,000 individuals, who are traced annually. The empirical strategy consists of ordinary least squares (OLS) and multinomial logistic estimators to measure changes in job income, work status, working hours, and pension as a result of reporting a cancer diagnosis for the period between 2009 and 2015. Sample consistency checks were conducted to limit measurement error biases. Results: Our results show that job incomes dropped between 26% and 28% within the year a cancer diagnosis was reported. The effect persisted for two years after the diagnosis and was no longer observable after four years. The finding was linked to an increased likelihood of unemployment and a reduction of working hours by 24%. Pension levels, on the other hand, were not affected by a cancer diagnosis. Conclusions: These findings suggest that many cancer patients are exposed to financial hardship in Germany, particularly when the cancer diagnosis occurs during their working age and before requirements to obtain a pension are met. Further research seems warranted to identify particularly vulnerable patient groups. [ABSTRACT FROM AUTHOR]

Screening tools developed for Western populations have produced heterogeneous prevalence estimates for depression and anxiety disorders among refugees. The use of these instruments assumes that psychopathological symptoms are manifested similarly across different cultural groups. Here, we scrutinized whether depressive and anxiety symptoms are manifested similarly between German residents and refugees in Germany. We tested measurement invariance, test information and specifics of symptom interrelations in 200 refugees and 202 German residents with classical test theory (CTT), item response theory (IRT) and network analysis. Participants completed the Patient Health Questionnaire regarding depressive and anxiety symptoms in either Arabic or German. Measurement invariance was only present to a certain extent. Questionnaires were most informative on different spectrums of the latent traits for the two groups. Network analysis demonstrated that symptom interrelations of depressive and anxiety symptoms differed across residents and refugees. This was especially true for core symptoms of common nosological systems, such as losing interest or feeling depressed. Surprisingly, traumatic events in the past were not central in refugees' anxiety networks. Core symptoms of nosological systems seem to be differently pronounced in refugees and residents, which has important implications for our understanding of mental health symptoms in refugees. [ABSTRACT FROM AUTHOR]

In this paper, we ask whether interviewers influence the answers to a standard set of survey questions on financial literacy. We study data from Germany's wealth survey, the Panel on Household Finances (PHF). We have access to extensive auxiliary data, including interviewer identifiers, background characteristics of interviewers and measures of interviewer activity through the survey. We find that interviewer effects explain a significant fraction of the variance of the financial literacy score, and intra‐interviewer correlations are notably larger for the financial literacy score than for other survey variables. We explore how accounting for interviewer effects can improve estimates of the effects of financial literacy on financial behaviours and outcomes. [ABSTRACT FROM AUTHOR]

Groundwater levels are monitored by environmental agencies to support the sustainable use of groundwater resources. For this purpose continuous and spatially comprehensive monitoring in high spatial and temporal resolution is desired. This leads to large datasets that have to be checked for quality and analysed to distinguish local anthropogenic influences from natural variability of the groundwater level dynamics at each well. Both technical problems with the measurements as well as local anthropogenic influences can lead to local anomalies in the hydrographs. We suggest a fast and efficient screening method for the identification of well-specific peculiarities in hydrographs of groundwater head monitoring networks. The only information required is a set of time series of groundwater heads all measured at the same instants of time. For each well of the monitoring network a reference hydrograph is calculated, describing expected "normal" behaviour at the respective well as is typical for the monitored region. The reference hydrograph is calculated by multiple linear regression of the observed hydrograph with the "stable" principal components (PCs) of a principal component analysis of all groundwater head series of the network as predictor variables. The stable PCs are those PCs which were found in a random subsampling procedure to be rather insensitive to the specific selection of the analysed observation wells, i.e. complete series, and to the specific selection of measurement dates. Hence they can be considered to be representative for the monitored region in the respective period. The residuals of the reference hydrograph describe local deviations from the normal behaviour. Peculiarities in the residuals allow the data to be checked for measurement errors and the wells with a possible anthropogenic influence to be identified. The approach was tested with 141 groundwater head time series from the state authority groundwater monitoring network in northeastern Germany covering the period from 1993 to 2013 at an approximately weekly frequency of measurement. [ABSTRACT FROM AUTHOR]

Pluvial or flash floods generated by heavy precipitation events cause large economic damage and loss of life worldwide. As discharge observations from such extreme occurrences are rare, especially on the scale of small catchments or even hillslopes, data from artificial sprinkling experiments offer valuable information on runoff generation processes, overland and subsurface flow rates, and response times. We conducted 132 large-scale sprinkling experiments on natural hillslopes at 23 sites with different soil types and geology on pastures and arable land within the federal state of Baden-Württemberg in south-western Germany. The experiments were realized between 2016 and 2017. Simulated rainfall events of varying durations were based on (a) the site-specific 100-year return periods of rainfall with different durations and (b) the maximum rainfall intensity observed locally. The 100 m 2 experimental area was divided into three individual plots, and overland and subsurface flow, soil moisture, and water level dynamics in the temporarily saturated soil zone were measured at 1 min resolution. Furthermore, soil characteristics were described in detail for each site. The data were carefully processed and corrected for measurement errors and combined into a consistent and easy-to-use database. The experiments revealed large variability in possible runoff responses to similar rainfall characteristics. In general, agricultural fields produced more overland flow than grassland. The latter generated hardly any runoff during the first simulated 100-year event on initially dry soils. The data set provides valuable information on runoff generation variability from natural hillslopes and may be used for the development and evaluation of hydrological models, especially those considering physical processes governing runoff generation during extreme precipitation events. The data set presented in this paper is freely available from the FreiDok plus data repository at 10.6094/UNIFR/151460 (Ries et al., 2019). [ABSTRACT FROM AUTHOR]

The accuracy of computer numerical control machine tools can be improved by identifying error sources affecting the overall position error and orientation errors. Because of their inevitable nature, the position errors cannot be entirely eliminated from the machinery, but they can be identified, measured and compensated during the manufacturing process of the components by developing and using a mathematical model. In this present work, different mathematical models have been developed for the errors measured by laser interferometer at different nominal positions of X, Y and Z axes both in forward and reverse direction movement as per VDI 3441 Germany standard. Using Akaike information criterion, the best model is selected for each axis and later the best model's coefficients have been optimized by considering both minimizing sum square errors and maximizing R 2 values using teaching–learning-based optimization algorithm. Technique for Order Preference by Similarity to the Ideal Solution method has been adopted to convert the dual objectives into a single objective. An improvement of 1%–71% in R 2 values was reported to prove the effectiveness of the proposed optimization algorithm, Teaching–Learning-Based Optimization algorithm, with the same sum square error values. [ABSTRACT FROM AUTHOR]

Pluvial or flash floods generated by heavy precipitation events cause high economic damages and loss of life worldwide. As discharge observations from such extreme occurrences are rare especially on the scale of small catchments or even hillslopes, data from artificial sprinkling experiments offer valuable information on runoff generation processes, overland and subsurface flow rates and response times. We conducted 132 large-scale sprinkling experiments on natural hillslopes at 23 sites with different soil types and geology on pastures and arable lands within the federal state of Baden-Württemberg in south-west Germany. The experiments were realized between 2016 and 2017. Simulated rainfall events of varying durations were based on a) the site-specific 100-year return periods of rainfall with different durations and b) the maximum rainfall intensity observed locally. The 100 m² experimental area was divided into three individual plots and overland and subsurface flow, soil moisture and water level dynamics in the temporarily saturated soil zone were measured at 1-minute resolution. Furthermore, soil characteristics were described in detail for each site. The data was carefully processed and corrected for measurement errors and combined to a consistent and easy to use database. The experiments revealed a large variability of possible runoff responses to similar rainfall characteristics. In general, agricultural fields produced more overland flow than grassland. The latter generated hardly any runoff during the first simulated 100-year event on initially dry soils. The dataset provides valuable information on runoff generation variability from natural hillslopes and may be used for the development and evaluation of hydrological models, especially those considering physical processes governing runoff generation during extreme precipitation events. [ABSTRACT FROM AUTHOR]

Featured Application: In consideration of relatively stable outcomes with the application of a correction factor for relative humidity, recently introduced inexpensive real-time monitors (IRMs), ESCORTAIR (ESCORT, Seoul, Korea) or PurpleAir (PA) (PurpleAir U.S.A.), our study supports their usage in PM2.5 monitoring for various urban hotspots. Inexpensive (<$300) real-time particulate matter monitors (IRMs), using laser as a light source, have been introduced for use with a Wi-Fi function enabling networking with a smartphone. However, the information of measurement error of these inexpensive but convenient IRMs are still limited. Using ESCORTAIR (ESCORT, Seoul, Korea) and PurpleAir (PA) (PurpleAir U.S.A.), we evaluated the performance of these two devices compared with the U.S. Environmental Protection Agency (EPA) Federal Equivalent Monitoring (FEM) devices, that is, GRIMM180 (GRIMM Aerosol, Germany) for the indoor measurement of pork panfrying or secondhand tobacco smoking (SHS) and Beta-ray attenuation monitor (BAM) (MetOne, Grants Pass, OR) for outdoor measurement at the national particulate matter (PM2.5) monitoring site near an urban traffic hotspot in Daejeon, South Korea, respectively. The PM2.5 concentrations measured by ESCORTAIR and PA were strongly correlated to FEM (r = 0.97 and 0.97 from indoor pan frying; 0.92 and 0.86 from indoor SHS; 0.85 and 0.88 from outdoor urban traffic hotspot). The two IRMs showed that PM2.5 mass concentrations were increased with increased outdoor relative humidity (RH) levels. However, after applying correction factors for RH, the Median (Interquartile range) of difference compared to FEM was (14.5 (6.1~23.5) %) for PA and 16.3 (8.5–28.0) % for ESCORTAIR, supporting their usage in the home or near urban hotspots. [ABSTRACT FROM AUTHOR]

This recommendation aims to provide up-to-date information and the latest consensus on diabetes diagnosis from a group of experts in Germany. The disease diabetes mellitus is classified and its different types are described briefly. Options for diagnosis are presented including current cut-off values as well as reference intervals to recognize glucose utilization disorders like impaired fasting glucose or impaired glucose tolerance. Special attention is paid to the measurement value imprecision. The minimal difference (MD) is introduced as an excellent measure to distinguish measurement results which are analytically different from each other. Potential caveats considering pre-analytics in glucose measurement and limitations of HbA1c assessment for diagnosis of diabetes mellitus are presented. Taken together, this recommendation provides a comprehensive overview of the state of the art in diabetes mellitus diagnosis and also critically evaluates potential pitfalls. The aim of recommendations like this one issued by the German Diabetes Association is to provide the diabetologist and his team the information he needs for his daily practice. These recommendations are updated annually. They are written by a group of experts, but they are not evidence-based guidelines. This specific recommendation for diabetes diagnosis briefly describes the diabetes types and the different options for diagnosis. Also the caveats and the practical procedure are presented. [ABSTRACT FROM AUTHOR]

Eating out is often recorded through short-term measurements and the large within-person variability in intakes may not be adequately captured. The present study aimed to understand the effect of measurement error when using eating-out data from one or two 24 h dietary recalls (24hDR), in order to describe intakes and assess associations between eating out and personal characteristics. In a sample of 366 adults from Potsdam, Germany, two 24hDR and a FFQ were collected. Out-of-home intakes were estimated based on either one 24hDR or two 24hDR or the Multiple Source Method (MSM) combining the two 24hDR and the questionnaire. The distribution of out-of-home intakes of energy, macronutrients and selected foods was described. Multiple linear regression and partial correlation coefficients were estimated to assess associations between out-of-home energy intake and participants' characteristics. The mean daily out-of-home intakes estimated from the two 24hDR were similar to the usual intakes estimated through the MSM. The out-of-home energy intake, estimated through either one or two 24hDR, was positively associated with total energy intake, inversely with age and associations were stronger when using the two 24hDR. A marginally significant inverse association between out-of-home energy intake and physical activity at work was observed only on the basis of the two 24hDR. After applying the MSM, all significant associations remained and were more precise. Data on eating out collected through one or two 24hDR may not adequately describe intake distributions, but significant associations between eating out and participants' characteristics are highly unlikely to appear when in reality these do not exist. [ABSTRACT FROM PUBLISHER]

Background: Since developmental psychologists are interested in explaining age and gender differences in depression across adolescence, it is important to investigate to what extent these observed differences can be attributed to measurement bias. Measurement bias may arise when the phenomenology of depression varies with age or gender, i.e., when younger versus older adolescents or girls versus boys differ in the way depression is experienced or expressed. Methods: The Children's Depression Inventory (CDI) was administered to a large school population ( N = 4048) aged 8-17 years. A 4-factor model was selected by means of factor analyses for ordered categorical measures. For each of the four factor scales measurement invariance with respect to gender and age (late childhood, early and middle adolescence) was tested using item response theory analyses. Subsequently, to examine which items contributed to measurement bias, all items were studied for differential item functioning (DIF). Finally, it was investigated how developmental patterns changed if measurement biases were accounted for. Results: For each of the factors Self-Deprecation, Dysphoria, School Problems, and Social Problems measurement bias with respect to both gender and age was found and many items showed DIF. Developmental patterns changed profoundly when measurement bias was taken into account. The CDI seemed to particularly overestimate depression in late childhood, and underestimate depression in middle adolescent boys. Conclusions: For scientific as well as clinical use of the CDI, measurement bias with respect to gender and age should be accounted for. [ABSTRACT FROM AUTHOR]

Abstract: We consider a difference based ridge regression estimator and a Liu type estimator of the regression parameters in the partial linear semiparametric regression model, . Both estimators are analyzed and compared in the sense of mean-squared error. We consider the case of independent errors with equal variance and give conditions under which the proposed estimators are superior to the unbiased difference based estimation technique. We extend the results to account for heteroscedasticity and autocovariance in the error terms. Finally, we illustrate the performance of these estimators with an application to the determinants of electricity consumption in Germany. [Copyright &y& Elsevier]

Background: To compare the measurement error of Cirrus HD-OCT and Heidelberg Retina Tomograph 3 (HRT3) in patients with early glaucomatous visual field defect. Methods: Thirty-nine consecutive patients (39 eyes) with early glaucomatous visual field defect were included. One eye of a patient was examined with Cirrus HD-OCT and HRT3 in one session. Each instrument was used by two operators, each taking two measurements in turn. We performed measurements of average retinal nerve fiber layer (RNFL) thickness and RNFL thickness in four quadrants with Cirrus HD-OCT and 13 stereometric parameters of the optic nerve head and RNFL with HRT3. Results: Cirrus HD-OCT parameters performed much better than HRT3 stereometric parameters. Mean (for both operators) intraoperator within-subject coefficient of variation of the best Cirrus HD-OCT parameter (average RNFL thickness) was 2.6-2.7 times lower than the best HRT3 parameters [mean cup depth and rim area ( P < 0.001)]. Mean intraoperator variability of RNFL thickness in quadrants (except nasal quadrant) was also significantly lower with OCT than with HRT. The interoperator within-subject coefficients of variation for both average RNFL thickness and RNFL thickness in all quadrants were significantly lower than the interoperator variability of best HRT3 parameter [mean cup depth ( P < 0.001)]. The within-subject coefficient of variation of the average/mean RNFL thickness assessed by both instruments was 5.4-7.3 times lower for Cirrus HD-OCT. Among HRT3 parameters, mean cup depth, rim area and linear cup/disk ratio were the least variable, while cup volume, cup area and cup/disc area ratio were the most variable parameters. Conclusions: Cirrus HD-OCT provides excellent intrasession intra- and interoperator repeatability of the RNFL measurements, especially of the average RNFL thickness in primary open-angle glaucoma (POAG) patients and POAG suspects with early glaucomatous visual field defect. The measurement error (expressed as within-subject coefficient of variation) of RNFL measurements by Cirrus HD-OCT is much lower than the error of HRT3 measurements of stereometric parameters of the optic nerve head and RNFL. [ABSTRACT FROM AUTHOR]

The precise determination of the He/H mass ratio, and hence the tritium β-decay endpoint energy E, is of relevance for the measurement of the electron anti-neutrino mass performed by the Karlsruhe Tritium Neutrino experiment (KATRIN). By determining this ratio to an uncertainty of 1 part in 10, systematic errors of E can be checked in the data analysis of KATRIN. To reach this precision, a Penning Trap Mass Spectrometer was constructed at the University of Washington and has been transferred to the Max Planck Institute for Nuclear Physics in Heidelberg at the end of 2008. Since then it is called MPIK/UW-PTMS. Special design features are the utilization of an external ion source and a double trap configuration. The external Penning ion source efficiently ionizes the helium and tritium gas and can give superior elimination of unwanted ion species compared to the previously utilized in-trap-ionization by electrons from a field-emission point. The design as a double Penning trap allows a faster measurement procedure. This should help to avoid problems resulting from long-term drifts in the experimental conditions. Additionally, the laboratory in Heidelberg was carefully prepared to have very stable environmental conditions. Experimental challenges and the first Heidelberg results with the new spectrometer are presented. [ABSTRACT FROM AUTHOR]

Errors of measuring time dependences of the light intensities of picosecond laser pulses by two electron-optical systems are studied. The first system is the picosecond streak camera made in Russia, and the second system, designed in Germany, consists of a picosecond streak camera coupled with a double spec-trograph. The manufacturers test similar systems by using femtosecond pulses, however, this does not allow one to predict errors of measuring picosecond pulses. Parameters that characterize just these errors are proposed and measured. Their behavior is determined, when the amplitude (energy) of the measured pulses increases, and the influence of the cross-section shape of the light beam on the measurement accuracy is studied. [ABSTRACT FROM AUTHOR]

Abstract: A set of tools for the statistical assessment of ocean observing networks is presented and applied for the analysis of different instrumentation scenarios in the German Bight. An optimal linear estimator is used to re-construct ocean state parameters from observations taking into account both the prior distribution of the state and measurement errors. The proposed method enables a re-construction of any scalar parameter or vector field with linear relationship to the state. The performance of the observing network is quantified in terms of the re-construction quality. Apart from the capability of the network to provide estimates of state parameters at the time of the observations, the potential of the measurements for forecasts is investigated as well. Furthermore, a generic method to compare single measurements with continuous observations is presented. Finally, a technique is described to quantify the relative importance of different components of an observational network. The proposed methods are applied to water level measurements in the German Bight. A numerical model is used to estimate the background statistics. Synthetic measurements provided by tide gauges, satellite altimeters, and HF radar are considered in the analysis. The estimation of the complete water level field in the German Bight is compared for altimeter and tide gauge measurements. It is shown that the orientation of the satellite track with respect to the coastline is of high relevance. The importance of water level measurements taken in deeper water, e.g., at the FINO-1 platform, is demonstrated. It is shown that continuous tide gauge measurements provide more information on the area mean water level in the German Bight than altimeter observations taken by ENVISAT and JASON-1/2. It is furthermore shown how the information provided by a tide gauge propagates with the Kelvin wave. Implications for the design of an assimilation scheme are discussed. [Copyright &y& Elsevier]

Nighttime lights are routinely used as a proxy for economic activity when official statistics are unavailable and are increasingly applied to study the effects of shocks or policy interventions at small geographic scales. The implicit assumption is that the ability of nighttime lights to pick up changes in GDP does not depend on local characteristics of the region under investigation or the scale of aggregation. This study uses panel data on regional GDP growth from six countries, and nighttime lights from the Defense Meteorological Satellite Program (DMSP) to investigate potential nonlinearities and measurement errors in the light production function. Our results for high statistical capacity countries (the United States and Germany) show that nightlights are significantly less responsive to changes in GDP at higher baseline level of GDP, higher population densities, and for agricultural GDP. We provide evidence that these nonlinearities are too large to be caused by differences in measurement errors across regions. We find similar but noisier relationships in other high-income countries (Italy and Spain) and emerging economies (Brazil and China). We also present results for different aggregation schemes and find that the overall relationship, including the nonlinearity, is stable across regions of different shapes and sizes but becomes noisier when regions become few and large. These findings have important implications for studies using nighttime lights to evaluate the economic effects of shocks or policy interventions. On average, nighttime lights pick up changes in GDP across many different levels of aggregation, down to relatively small geographies. However, the nonlinearity we document in this paper implies that some studies may fail to detect policy-relevant effects in places where lights react little to changes in economic activity or they may mistakenly attribute this heterogeneity to the treatment effect of their independent variable of interest. [ABSTRACT FROM AUTHOR]

Use of a digital preparation assistant system may improve considerably the quality of preclinical dental education, provided the system works reliably. Thus, the purpose of this pilot study was to quantitatively assess the reliability of a new preclinical digital preparation assistant system (PREPassist, KaVo, Germany). The system was used to repeatedly scan four different unprepared and four different prepared teeth both with and without repositioning. Corresponding measurements were made to quantify accuracy, repeatability, and reproducibility. This was done by estimating the measurement error. Based on this estimation, respective limits of agreement were calculated. We used these ranges, along with assessments of the measurement's accuracy, to judge whether the results satisfy our expectations for clinically acceptable measurements. For preclinical laboratory instruction, the results indicate an acceptable accuracy (mean accuracy of 89 μm) of the measurements. This assessment applies as well to repeatability, given by the range of the respective limits of agreement (range <200 μm). However, in the case of reproducibility, the limits revealed discrepancies of practical importance (range >200 μm). Reproducibility of tooth repositioning in the available mounting device is unacceptable for preclinical laboratory instruction because of the observed range >200 μm. Thus, there is a need for the manufacture of new and more reliable mounting devices because reproducibility procedures are mostly encountered in preclinical instruction in restorative techniques. In contrast to reproducibility, accuracy and repeatability are acceptable for practical purposes. Balancing advantages and disadvantages, we conclude that, in general, the PREPassist system delivers reliable results. [ABSTRACT FROM AUTHOR]

This paper tests the Expectations Hypothesis (EH) of the term structure of interest rates using new data for Germany. The German term structure appears to forecast future short-term interest rates surprisingly well, compared with previous studies with US data, while it has lower predictive power for long-term interest rates. However, the direction suggested by the coefficient estimates is consistent with that implied by the EH, that is when the term spread widens, long rates increase. The use of instrumental variables to deal with possible measurement errors in the data significantly improves regressions for the long rates. Moreover, re-estimation with proxy variables to account for the possibility of time-varying term premia confirms that the evolution of both short and long rates corresponds to the predictions of the EH and that most of the information is in the term spread. These results are important as they suggest that monetary policy in Germany could be guided by the slope of the term structure. [ABSTRACT FROM AUTHOR]

Background: A psychometrically robust measurement instrument is prerequisite to tailor and monitor interventions aiming to improve evidence-based practice (EBP). The recently developed "Evidence-based Practice Inventory" (EBPI) questionnaire (five dimensions) provides a sound inventory for a comprehensive assessment of adherence to EBP, and identification of barriers and facilitators for EBP. The aims of this study were to establish a German language version of the EBPI and to examine the instrument's reliability in a diverse sample of healthcare professionals.Methods: The English version of the EBPI was translated, adopted and subsequently test-retest reliability of the German language EBPI was examined in a nationwide online survey. Participants working in Germany were invited to complete the questionnaire twice. For each EBPI dimension, internal consistency reliability (Cronbach's alpha) and the relative test-retest reliability (intraclass correlation coefficient, ICC) were calculated. The standard error of measurement, limits of agreement and minimal detectable change values were estimated to quantify measurement error.Results: A German language version of the EBPI was established. In the online survey, the EBPI was initially completed by 889 healthcare professionals. At follow-up, 344 individuals (39%) completed the questionnaire (74% female; mean work experience: 13.6 years). The ICCs for the five dimensions varied between 0.78 and 0.86. The standard error of measurement varied between 6.5 and 8.8% of the respective dimension scale range, and the limits of agreement between 24 and 37%. For internal consistency reliability, alpha varied between 0.64 and 0.90. There were neither floor nor ceiling effects, nor any other relevant feasibility issues.Conclusions: The German language EBPI can be used to assess EBP adherence of healthcare professionals in clinical practice, and to identify barriers and facilitators for an EBP conform behaviour. Results on test-retest reliability indicate that the EBPI produces reliable scores when used for group comparisons, but the questionnaire seems insufficiently reliable for individual measurements over time. Methods of item response theory or Rasch measurement theory should be used for further evaluation and revision of the EBPI, informed by the results of this study.Trial Registration: German Clinical Trials Register ( DRKS00013792 ). Registered 19 January 2018. [ABSTRACT FROM AUTHOR]