Dual-FOV Raman and Doppler lidar studies of aerosol-cloud interactions : Simultaneous profiling of aerosols, warm-cloud properties, and vertical wind

Date of Acceptance: 24/04/2014 This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are madeFor the first time, colocated dual-field of view (dual-FOV) Raman lidar and Doppler lidar observations (case studies) of aerosol and cloud optical and microphysical properties below and within thin layered liquid water clouds are presented together with an updraft and downdraft characterization at cloud base. The goal of this work is to investigate the relationship between aerosol load close to cloud base and cloud characteristics of warm (purely liquid) clouds and the study of the influence of vertical motions and turbulent mixing on this relationship. We further use this opportunity to illustrate the applicability of the novel dual-FOV Raman lidar in this field of research. The dual-FOV lidar combines the well-established multiwavelength Raman lidar technique for aerosol retrievals and the multiple-scattering Raman lidar technique for profiling of the single-scattering extinction coefficient, effective radius, number concentration of the cloud droplets, and liquid water content. Key findings of our 3 year observations are presented in several case studies of optically thin altocumulus layers occurring in the lower free troposphere between 2.5 and 4 km height over Leipzig, Germany, during clean and polluted situations. For the clouds that we observed, the most direct link between aerosol proxy (particle extinction coefficient) and cloud proxy (cloud droplet number concentration) was found at cloud base during updraft periods. Above cloud base, additional processes resulting from turbulent mixing and entrainment of dry air make it difficult to determine the direct impact of aerosols on cloud processes.Peer reviewedFinal Published versio

Towards a Semantic Data Quality Management - Using Ontologies to Assess Master Data Quality in Retailing

Since its inception Information Systems has relied heavily on older, more established, reference disciplines for much of its theory development and practical application. The relationship between the economic sciences and information quality has been the subject of much of the work recognized through the Nobel Prize in Economic Sciences. Beginning with Simon’s decision-making model published before a discipline known as Information Systems existed, this paper reviews this relationship and the parallel development of information quality and computing capability from an Information System perspective and changing paradigms in economics as recognized in the works of the Nobel laureates. From economic theories based on assumed knowledge, the paradigm is shifting to methods of empirical testing and experimentation. Organizations continue to make operational and strategic decisions. Additionally, now information is being aggregated, warehoused, mined, and analyzed to make a host of societal decisions and to understand economic behaviors through experimentation and empirical analysis

Rituximab-Containing Treatment Regimens May Imply a Long-Term Risk for Difficult-To-Treat Chronic Hepatitis E

Hepatitis E virus (HEV) infection is an emerging disease in industrialized countries which is usually characterized by a self-limited course. However, there is an increased risk of HEV persistence in immunocompromised risk populations, comprising patients following solid organ transplantation or hematological malignancies. Recently, chronic HEV infection following rituximab-containing treatment regimens has been described. Here we report five patients with chronic hepatitis E after prior rituximab therapy for various indications. We determined the immunological characteristics of these patients and analyzed the development of ribavirin (RBV) treatment failure-associated mutations in the HEV genome. One patient became chronically HEV-infected 110 months after administration of rituximab (RTX). Immunological characterization revealed that all patients exhibited significant hypogammaglobulinemia and CD4+ T cell lymphopenia. One patient permanently cleared HEV following weight-based ribavirin treatment while three patients failed to reach a sustained virological response. In depth mutational analysis confirmed the presence of specific mutations associated with RBV treatment failure in these patients. Our cases indicate that rituximab-containing treatment regimens might imply a relevant risk for persistent HEV infection even years after the last rituximab application. Moreover, we provide further evidence to prior observations suggesting that chronically HEV infected patients following RTX-containing treatment regimens might be difficult to treat

Modeling, Customer-Specific Configuration and Calculation of Bundles

Customers in B2B as well as B2C markets increasingly demand integrated problem solutions from their suppliers, comprising both physical artifacts (products) and services. Applying a mixed-bundling strategy to offer such value bundles to customers foremost requires a sound configuration and economic calculation of value propositions, based on previously defined modules of products and services. In this paper, a modeling language is introduced to describe the function and structure of such modules, as well as to calculate the economic consequences of value propositions on a customer-individual level. The proposed modeling language has been embedded into a software tool to evaluate its utility regarding the customization and offering of integrated value bundles to customers

Managing Creative Risks

Business process management (BPM) has emerged as an important enabler for managing risks. Organizations use BPM techniques such as process modeling to create transparency and to identify process-related risks. Existent risk management frameworks distinguish between different types of risk, such as people, technical, and management risk. Our study suggests that creativity in business processes leads to a particular subset of risks which organizations respond to by applying specific strategies of risk avoidance and mitigation. These creative risks occur within business processes as different people come together to generate creative products. These people bring in different perceptions of creativity and aesthetics and solve creative tasks in different ways. Thus, business processes that involve creativity are characterized by a high variance both in process flow and process outcome which can lead to unwanted consequences. Based on interpretive case studies we introduce the concept of creative risk and explain what strategies organizations can apply to handle it

Simultaneous attenuation of trace organics and change in organic matter composition in the hyporheic zone of urban streams

Trace organic compounds (TrOCs) enter rivers with discharge of treated wastewater. These effluents can contain high loads of dissolved organic matter (DOM). In a 48 h field study, we investigated changes in molecular composition of seven DOM compound classes (FTICR-MS) and attenuation of 17 polar TrOCs in a small urban stream receiving treated wastewater. Correlations between TrOCs and DOM were used to identify simultaneous changes in surface water and the hyporheic zone. Changes in TrOC concentrations in surface water ranged between a decrease of 29.2% for methylbenzotriazole and an increase of 152.2% for the transformation product gabapentin-lactam. In the hyporheic zone, only decreasing TrOC concentrations were observed, ranging from 4.9% for primidone to 93.8% for venlafaxine . TrOC attenuation coincided with a decline of molecular diversity of easily biodegradable DOM compound classes while molecular diversity of poorly biodegradable DOM compound classes increased. This concurrence indicates similar or linked attenuation pathways for biodegradable DOM and TrOCs. Strong correlations between TrOCs and DOM compound classes as well as high attenuation of TrOCs primarily occurred in the hyporheic zone. This suggests high potential for DOM turnover and TrOC mitigation in rivers if hyporheic exchange is sufficient.German Research Foundation (DFG)European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreementBattelle Memorial Institute for the U.S. Department of EnergyPeer Reviewe

Seasonal Differences in the Attenuation of Polar Trace Organics in the Hyporheic Zone of an Urban Stream

Attenuation of trace organic compounds (TrOCs) in a river occurs to a large extent in its hyporheic zone. A major part of the attenuation of polar TrOCs is of microbial origin. As microbial activity depends on temperature and redox conditions, seasonal differences in TrOC attenuation are likely. We investigated TrOC attenuation at a river influenced by treated wastewater during two sampling campaigns, one in summer and one in winter. In addition to redox conditions and temperature, we also determined residence times of porewater in sediment using three methods: (a) non‐parametric deconvolution of electrical conductivity time series, (b) the model VFLUX 2.0 based on temperature time series (only summer), and (c) applying Darcy's law to differences in hydraulic heads (only summer). Contrary to our expectations, we found higher attenuation for 12 out of 18 TrOCs in winter, while three TrOCs were better attenuated in summer. Sediment conditions varied between seasons as more of the top sandy layer with a higher hydraulic permeability accumulated on the river bed in summer. As a result, residence times in the sediment were shorter in summer. In winter, longer residence times, lower temperatures, and a steeper oxygen gradient in sediment coincided with higher TrOC attenuation. Further research is needed to understand our unexpected findings and underlying mechanisms.Key Points The attenuation of 12 out of 18 trace organic compounds (TrOCs) in the hyporheic zone was higher in winter while three TrOCs were attenuated better in summer Residence times in sediment were longer and more diverse in winter The extent of the oxic sediment was similar between seasons but the gradient from the oxic to anoxic zone was steeper in winterDeutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659EC | H2020 | H2020 Priority Excellent Science | H2020 Marie Skłodowska‐Curie Actions (MSCA) http://dx.doi.org/10.13039/100010665University of Western Australia ‐ University Postgraduate AwardAustralian Government Research Training Program ScholarshipBundesministerium für Bildung und Forschung (BMBF) http://dx.doi.org/10.13039/501100002347Peer Reviewe

A Framework for Design Research in the Service Science Discipline

The emerging discipline of Service Science Management and Engineering (SSME) apart from developing theories strives to build and evaluate IT artifacts of utility for the service economy. Especially due to the interdisciplinary character of this new discipline and the imprint of rather behavioral science oriented disciplines, for some problem areas only few innovative artifacts have been scientifically published and evaluated. To counter this deficiency, we present a research framework for design research in the service science discipline. The framework is based on design (science) research literature and widely acknowledged service science perspectives. It addresses three dimensions: (1) four IT artifact types, (2) four perspectives on the service science, and (3) three levels of abstraction. Using the framework, gaps in the service science discipline yet to be addressed by IT artifacts can be identified. On the other hand, if abundant IT artifacts can be identified for any of the proposed research areas, artifacts might need to be systematized or combined

Extreme climatic events down-regulate the grassland biomass response to elevated carbon dioxide

Terrestrial ecosystems are considered as carbon sinks that may mitigate the impacts of increased atmospheric CO2 concentration ([CO2]). However, it is not clear what their carbon sink capacity will be under extreme climatic conditions. In this study, we used long-term (1998–2013) data from a C3 grassland Free Air CO2 Enrichment (FACE) experiment in Germany to study the combined effects of elevated [CO2] and extreme climatic events (ECEs) on aboveground biomass production. CO2 fertilization effect (CFE), which represents the promoted plant photosynthesis and water use efficiency under higher [CO2], was quantiffied by calculating the relative differences in biomass between the plots with [CO2] enrichment and the plots with ambient [CO2]. Down-regulated CFEs were found when ECEs occurred during the growing season, and the CFE decreases were statistically significant with p well below 0.05 (t-test). Of all the observed ECEs, the strongest CFE decreases were associated with intensive and prolonged heat waves. These findings suggest that more frequent ECEs in the future are likely to restrict the mitigatory effects of C3 grassland ecosystems, leading to an accelerated warming trend. To reduce the uncertainties of future projections, the atmosphere-vegetation interactions, especially the ECEs effects, are emphasized and need to be better accounted

MonTM: Monitoring-Based Thermal Management for Mixed-Criticality Systems

With a rapidly growing functionality of embedded real-time applications, it becomes inevitable to integrate tasks of different safety integrity levels on one many-core processor leading to a large-scale mixed-criticality system. In this process, it is not sufficient to only isolate shared architectural resources, as different tasks executing on different cores also possibly interfere via the many-core processor’s thermal management. This can possibly lead to best-effort tasks causing deadline violations for safety-critical tasks. In order to prevent such a scenario, we propose a monitoring-based hardware extension that communicates imminent thermal violations between cores via a lightweight interconnect. Building on this infrastructure, we propose a thermal strategy such that best-effort tasks can be throttled in favor of safety-critical tasks. Furthermore, assigning static voltage/frequency (V/f) levels to each safety-critical task based on their worst-case execution time may result in unnecessary high V/f levels when the actual execution finishes faster. To free the otherwise wasted thermal resources, our solution monitors the progress of safety-critical tasks to detect slack and safely reduce their V/f levels. This increases the thermal headroom for best-effort tasks, boosting their performance. In our evaluation, we demonstrate our approach on an 80-core processor to show that it satisfies the thermal and deadline requirements, and simultaneously reduces the run-time of best-effort tasks by up to 45% compared to the state of the art