Search

Human long duration exploration missions (LDEMs) raise a number of technological challenges. This paper addresses the question of the crew autonomy: as the distances increase, the communication delays and constraints tend to prevent the astronauts from being monitored and supported by a real time ground control. Eventually, future planetary missions will necessarily require a form of astronaut self-scheduling. We study the usage of a computer decision-support tool by a crew of analog astronauts, during a Mars simulation mission conducted at the Mars Desert Research Station (MDRS, Mars Society) in Utah. The proposed tool, called Romie, belongs to the new category of Robust Advanced Modelling and Scheduling (RAMS) systems. It allows the crew members (i) to visually model their scientific objectives and constraints, (ii) to compute near-optimal operational schedules while taking uncertainty into account, (iii) to monitor the execution of past and current activities, and (iv) to modify scientific objectives/constraints w.r.t. unforeseen events and opportunistic science. In this study, we empirically measure how the astronauts, who are novice planners, perform at using such a tool when self-scheduling under the realistic assumptions of a simulated Martian planetary habitat.

Model validation for real-world systems involves multiple sources of uncertainty, multivariate model outputs, and often a limited number of measurement samples. These factors preclude the use of many existing validation metrics, or at least limit the ability of the practitioner to derive insights from computed metrics. This paper seeks to extend the area metric (univariate only) and the model reliability metric (univariate and multivariate) to account for these issues. The model reliability metric was found to be more extendable to multivariate outputs, whereas the area metric presented some difficulties. Metrics of different types (area and model reliability), dimensionality (univariate and multivariate), and objective (bias effects, shape effects, or both) are used together in a “multimetric” approach that provides a more informative validation assessment. The univariate metrics can be used for output-by-output model diagnosis and the multivariate metrics contributes an overall model assessment that includes correlation among the outputs. The extensions to the validation metrics in this paper address limited measurement sample size, improve the interpretability of the metric results by separating the effects of distribution bias and shape, and enhance the model reliability metric's tolerance parameter. The proposed validation approach is demonstrated with a bivariate numerical example and then applied to a gas turbine engine heat transfer model.

Exsolution generates stable and catalytically active metal nanoparticles via phase precipitation out of a host oxide. An ability to control the size and dispersion of the exsolution particles is desirable for design of nanostructured (electro)catalysts. Here, we demonstrate that tuning point defects by lattice strain affects both the thermodynamics and the kinetics of iron (Feo) exsolution on La0.6Sr0.4FeO3 (LSF) thin film model. By combining in situ surface characterization and ab initio defect modeling, we show oxygen vacancy and Schottky defects to be the primary point defects formed upon Feo exsolution. Lattice strain tunes the formation energy, and thus the abundance of these defects, and alters the amount and size of the resulting exsolution particles. In addition, we find that the density of exsolved nanoparticles matches the concentration of oxygen vacancy pairs, thus pointing to the surface oxygen vacancy pairs as preferential nucleation sites for exsolution. The tensile-strained LSF with a facile formation of these critical point defects results in a higher Feo metal concentration, a larger density of nanoparticles, and a reduced particle size at its surfaces. These results provide important mechanistic insights and highlight the role of point-defect engineering in designing nanostructured catalysts in energy and fuel conversion technologies.

Fragestellung: Evaluation des chirurgischen Langzeiterfolges nach Trabekulektomie (TE) und beeinflussender Faktoren in einer Kohorte von Patienten mit Offenwinkelglaukom. Methodik: Es wurde eine retrospektive Kohortenstudie von konsekutiven Patienten mit refraktärem Offenwinkelglaukom, die [zum vollständigen Text gelangen Sie über die oben angegebene URL]

This paper presents a novel surrogate modeling approach that enables the application of Bayesian calibration to a gas turbine disc finite element (FE) heat transfer model. The surrogate modeling pr...

An increasing product variance, shorter life cycles and the integration of new products and technologies into existing factories lead to a high complexity in today’s production systems. This makes it difficult to carry out Life Cycle Assessments (LCA) continuously and effectively. Major challenges of LCA are on the one hand a high expenditure of time and on the other hand a static evaluation of individual products. In order to perform dynamic and continuous process analyses, companies increasingly rely on new technologies and methods. Numerous studies have already been able to tap promising potentials by using Process Mining (PM). In contrast to traditional methods of process modeling, PM uses event log data to model the actual production processes. Based on this data, a real-time model is built to identify waste. In a holistic approach, PM is able to automatically uncover social and organizational networks and map them in a simulation model. According to the current state of research, there is no concept for integrating PM into LCA. Therefore, the present work focuses on the investigation of interfaces between PM and LCA in order to systematically identify and evaluate the potentials of using PM. The results are applied to a use case in the sector of commercial vehicles.

In consequence of the technological advances of the last few decades, factories emerged to highly complex systems that consist of numerous factory elements like production machines, technical building services and the building shell. These factory elements are characterized by individual life cycles that differ in their duration and life cycle behavior. Consequently, the factory life cycle is composed of multiple overlapping life cycles. The fact that the life cycle of some factory elements (e.g. the building shell) exceeds the life cycle of other elements over many times (e.g. of machines) presents a challenge for factory planners. In particular, factory planners struggle to understand the contribution of single factory elements on the total factory life cycle. Consequently, it is hard to systematically synchronize the inherent life cycles of a factory while adhering to manifold requirements. Against this background, the goal of this paper is to develop a methodology that supports factory planners in the evaluation of the factory life cycle. The proposed methodology enhances the understanding of how factory elements contribute to the factory life cycle and what is the current life cycle state of the entire factory. To this end, the factory system is broken down on its constituting elements. A modified failure mode and effect analysis (FMEA) is applied to assess their life cycle priority according to economic, environmental and technical criteria. The methodology is exemplarily demonstrated on a pilot scale battery production system.

Data on past vegetation compositions is crucial not only for understanding past vegetation dynamics and environmental interactions but also for predicting potential future vegetation trajectories and thus their feedback on climate and society. Pollen records from sediment cores provide temporally resolved data on pollen frequencies. These allow for inferences of taxa presence, but biased pollen deposition due to taxa-specific pollen productivity and dispersal prohibit direct inference of taxa abundance.The model for Regional Estimates of Vegetation Abundance from Large Sites (REVEALS) corrects for these taxa-specific parameters and produces more realistic regional vegetation abundances. Previously applied in many regions such as North America, Southern Sweden, Norway, and more recently the entirety of Europe, REVEALS has performed well in providing estimates for large vegetation units as well as individual taxa. With this data set, we present reconstructed past regional vegetation for more than 2200 sites across the Northern Hemisphere. The REVEALS model was applied by using a harmonized pollen dataset for the entire Northern Hemisphere, taxa-specific pollen productivity estimates, pollen fall speeds, as well as pollen dispersal models. First validations show an improved fit of the reconstructed vegetation with remotely sensed tree cover compared to pure pollen percentages. For validation tree cover datasets from the CONSENSUS global 1-km land cover product were used. The pollen source areas were defined to include 80% of the area from which deposited pollen originated.This first-time reconstruction for the entire Northern Hemisphere will allow for detailed analysis of vegetation dynamics and trajectories ultimately improving our understanding of climate-vegetation interactions, and may even act as input and validation for other vegetation and climate models and proxies.

[Fifteen patients with UC prior to or after local treatment underwent [Overall, 64 tumor sites were detected on PET and/or CT. The highest uptake intensity was noted at the primary site (SUV[

Purpose : Changes in lipid metabolism, chronic inflammation and increased oxidative stress have been discussed as patho-etiogenetic drivers in age-related macular degeneration (AMD). Systemic medication, such as lipid-lowering drugs (LLD) and anti-diabetic drugs, affect these pathways and may therefore also play a role in AMD pathogenesis. We aimed to investigate associations of commonly used systemic drugs with AMD prevalence in the European population.Methods : We included 38,694 adults from 14 population-based studies from the European Eye Epidemiology (E3) consortium. We performed multivariable logistic regression modelling to examine medication use association with prevalence of AMD as well as late AMD. Analyses were carried out separately by study and results pooled using random effects meta-analysis. We conducted these analyses separately for LLD, anti-diabetic drugs, non-steroidal anti-inflammatory drugs (NSAID), and L-Dopa.Results : Between studies, mean age ranged from 61.5 ± 7.1 to 82.6 ± 3.8 years and prevalence ranged from 12.1% to 64.5% and from 0.5% to 35.5% for any and any late AMD, respectively. In the meta-analysis of our multivariable models, LLD and anti-diabetic drugs were associated with lower AMD prevalence (OR 0.85, 95% confidence interval (CI)=0.79 - 0.91 and OR 0.78, 95% CI=0.66 - 0.91). We found no association with late AMD or with any other medication.Conclusions : Our study shows an association of LLD and anti-diabetic drug use with lower AMD prevalence across multiple European cohorts. Our findings support the importance of metabolic processes in the complex etiology of AMD.

Charge trapping plays an important role for the reliability of electronic devices and manifests itself in various phenomena like bias temperature instability (BTI), random telegraph noise (RTN), hysteresis or trap-assisted tunneling (TAT). In this work we present Comphy v3.0, an open source physical framework for modeling these effects in a unified fashion using nonradiative multiphonon theory on a one-dimensional device geometry. Here we give an overview about the underlying theory, discuss newly introduced features compared to the original Comphy framework and also review recent advances in reliability physics enabled by these new features. The usefulness of Comphy v3.0 for the reliability community is highlighted by several practical examples including automatic extraction of defect distributions, modeling of TAT in high-k capacitors and BTI/RTN modeling at cryogenic temperatures.

Purpose : To investigate the association of common systemic medication use with intraocular pressure and glaucoma prevalence in the European population.Methods : We examined associations of systemic medication use with intraocular pressure and glaucoma prevalence in a meta-analysis of multiple cohort studies of the European Eye Epidemiology (E3) consortium. IOP measurement method and glaucoma ascertainment were according to individual study protocols. Multivariable regression (linear for IOP and logistic for glaucoma prevalence) was carried out in each study and results pooled using random effects meta-analysis. Age, sex, body-mass index and diabetes were included as co-variables. Associations of antidiabetic medications were evaluated only in diabetic subjects.Results : A total of 46,845 participants from 11 population-based studies from the E3-consortium were included. In the meta-analysis of our fully-adjusted multivariable models, beta-blocker usage was associated with a lower IOP (all beta-blockers: Beta=-0.33 mmHg, 95% confidence interval (CI)=-0.58 to -0.08; non-selective betablockers: Beta=-0.56, 95% CI=-0.92 to -0.21; selective betablockers: Beta= -0.40, 95% CI=-0.64 to -0.16). In the meta-analysis of our fully-adjusted multivariable models, usage of calcium-channel blockers was positively associated with a higher glaucoma prevalence (all calcium-channel blockers: OR=1.25, 95% CI=1.05 to 1.50; selective calcium-channel blockers with mainly vascular effects: OR=1.27, 95% CI=1.05 to 1.53; selective calcium-channel blockers with direct cardiac effects: OR=1.54, 95% CI=1.07 to 2.21). Usage of RAS-inhibitors, diuretics, alpha-agonists, statins, fibrates, non-selective monoamine reuptake inhibitors, selective serotonin reuptake inhibitors, and antidiabetic medications was not associated with IOP or glaucoma.Conclusions : Our study supports and quantifies the known IOP-lowering effect of systemic beta-blockers, but there was no evidence of an IOP-lowering effect of other commonly used systemic medications. The usage of calcium-channel blockers (both with vascular and direct cardiac effects) was associated with a higher prevalence of glaucoma but not with higher IOP. Further studies are required to probe whether this harmful association of calcium-channel blockers with glaucoma is causal.

In 2019 and 2020, the layers - down to a maximum depth of 30 cm - of 43 soil samples from different regions in Austria were measured gamma-spectrometrically to determine their activity concentration (in Bq/kg and Bq/m³) of

To quantify the results of childhood glaucoma treatment over time in a cohort of children with different types of childhood glaucoma. A retrospective cohort study of consecutive cases involving children with primary congenital glaucoma, primary juvenile, and secondary juvenile glaucoma at the Childhood Glaucoma Center, University Medical Center Mainz, Germany from 1995 to 2015 was conducted. The main outcome measure was the long-term development of intraocular pressure. Further parameters such as surgical success, refraction, corneal diameter, axial length, and surgical procedure in children with different types of childhood glaucoma were evaluated. Surgical success was defined as IOP < 21 mmHg in eyes without a need for further intervention for pressure reduction. A total of 93 glaucomatous eyes of 61 childhood glaucoma patients with a mean age of 3.7 ± 5.1 years were included. The overall mean intraocular pressure at first visit was 32.8 ± 10.2 mmHg and decreased to 15.5 ± 7.3 mmHg at the last visit. In the median follow-up time of 78.2 months, 271 surgical interventions were performed (130 of these were cyclophotocoagulations). Many (61.9%) of the eyes that underwent surgery achieved complete surgical success without additional medication. Qualified surgical success (with or without additional medication) was reached by 84.5% of the eyes.

To quantify the results of childhood glaucoma treatment over time in a cohort of children with different types of childhood glaucoma. A retrospective cohort study of consecutive cases involving children with primary congenital glaucoma, primary juvenile, and secondary juvenile glaucoma at the Childhood Glaucoma Center, University Medical Center Mainz, Germany from 1995 to 2015 was conducted. The main outcome measure was the long-term development of intraocular pressure. Further parameters such as surgical success, refraction, corneal diameter, axial length, and surgical procedure in children with different types of childhood glaucoma were evaluated. Surgical success was defined as IOP < 21 mmHg in eyes without a need for further intervention for pressure reduction. A total of 93 glaucomatous eyes of 61 childhood glaucoma patients with a mean age of 3.7 ± 5.1 years were included. The overall mean intraocular pressure at first visit was 32.8 ± 10.2 mmHg and decreased to 15.5 ± 7.3 mmHg at the last visit. In the median follow-up time of 78.2 months, 271 surgical interventions were performed (130 of these were cyclophotocoagulations). Many (61.9%) of the eyes that underwent surgery achieved complete surgical success without additional medication. Qualified surgical success (with or without additional medication) was reached by 84.5% of the eyes.