493 research outputs found
Die Na-Li-Dual-Ionen-Batterie – Optimiertes Zelldesign und neuartige Elektrodenformulierungen zur Steigerung der Kapazitätsausnutzung
The Carbon Isotope Organic Geochemistry of Early Ordovician Rocks from the Annascaul Formation, County Kerry
Ireland is well known to geologists as containing some of the thickest successions of Early Ordovician (485-470 Ma; Walker et al. 2012) sedimentary rocks in the world. The carbon stable isotope compositions (δ13C value) of similarly aged rocks have been reported for only very few places in the world (i.e., Argentina, southern China, and southern France), and no such analyses have been performed on the Early Ordovician, organic-rich rocks of Ireland. Here we report the δ13C values of bulk organic material and organic isolates recovered from the Annascaul Formation of Southwestern Ireland. Members of the Annascaul Formation spanning the Early Ordovician were sampled at multiple sites within five localities on the Dingle Peninsula, County Kerry. Mean bulk organic δ13C values for the organic matter within rocks of the Farranacarriga, Tinal, Illaunglass, Bealacoon, and Killelton Members ranged from -28.7‰ (Farranacarriga) to -22.1‰ (Illaunglass); the average δ13C values of organics isolated from the Farranacarriga and Bealacoon Members were -29.0 and -28.4‰, respectively. No statistical difference was observed between the δ13C value of isolates and the δ13C value of bulk sediment from which organics had been isolated (P-0.85, Farranacarriga, n-6; P-0.81, Bealacoon, n-5; paired t-test). The δ13C values we present here agree well with the previously published δ13C values for Early Ordovician organic carbon (average = -28.4, -25.4, -25.5‰) from Argentina, southern China, and southern France (respectively). Our new data from the Annascaul Formation are ∼3.3‰ higher than the average value reported for δ13C values of organic matter of marine origin for the same period, raising the possibility that terrestrial bryophytes (or other terrestrial photosynthesizers) contributed to these Early Ordovician sediments. Further equivocal evidence is provided by the abundant organic macerals found within the Farranacarriga Member with possible vitrinite origin. The δ13C values of palynomorphsized organic isolates from the Annascaul Formation reflect a marine origin for these organisms, consistent with their previous identification as acritarchs. Given the recognition of the earliest thalloid macrofossils and land-plant cryptospores in the Middle Ordovician sediments of the Appalachian basin (USA) and Argentina, respectively, our results highlight the Early-Middle Ordovician boundary as a potentially crucial time of terrestrial ecosystem expansion and development
clustermq enables efficient parallelization of genomic analyses
Motivation: High performance computing (HPC) clusters play a pivotal role in large-scale bioinformatics analysis and modeling. For the statistical computing language R, packages exist to enable a user to submit their analyses as jobs on HPC schedulers. However, these packages do not scale well to high numbers of tasks, and their processing overhead quickly becomes a prohibitive bottleneck.Results: Here we present clustermq, an R package that can process analyses up to three orders of magnitude faster than previously published alternatives. We show this for investigating genomic associations of drug sensitivity in cancer cell lines, but it can be applied to any kind of parallelizable workflow.</p
Hybrid Energy Storage Systems Based on Redox-Flow Batteries: Recent Developments, Challenges, and Future Perspectives
Recently, the appeal of Hybrid Energy Storage Systems (HESSs) has been growing in multiple application fields, such as charging stations, grid services, and microgrids. HESSs consist of an integration of two or more single Energy Storage Systems (ESSs) to combine the benefits of each ESS and improve the overall system performance, e.g., efficiency and lifespan. Most recent studies on HESS mainly focus on power management and coupling between the different ESSs without a particular interest in a specific type of ESS. Over the last decades, Redox-Flow Batteries (RFBs) have received significant attention due to their attractive features, especially for stationary storage applications, and hybridization can improve certain characteristics with respect to short-term duration and peak power availability. Presented in this paper is a comprehensive overview of the main concepts of HESSs based on RFBs. Starting with a brief description and a specification of the Key Performance Indicators (KPIs) of common electrochemical storage technologies suitable for hybridization with RFBs, HESS are classified based on battery-oriented and application-oriented KPIs. Furthermore, an optimal coupling architecture of HESS comprising the combination of an RFB and a Supercapacitor (SC) is proposed and evaluated via numerical simulation. Finally, an in-depth study of Energy Management Systems (EMS) is conducted. The general structure of an EMS as well as possible application scenarios are provided to identify commonly used control and optimization parameters. Therefore, the differentiation in system-oriented and application-oriented parameters is applied to literature data. Afterwards, state-of-the-art EMS optimization techniques are discussed. As an optimal EMS is characterized by the prediction of the system’s future behavior and the use of the suitable control technique, a detailed analysis of the previous implemented EMS prediction algorithms and control techniques is carried out. The study summarizes the key aspects and challenges of the electrical hybridization of RFBs and thus gives future perspectives on newly needed optimization and control algorithms for management systems
Taming the Hurricane of Acquisition Cost Growth – Or At Least Predicting It
Cost growth is a persistent adversary to efficient budgeting in the Department of Defense. Despite myriad studies to uncover causes of this cost growth, few of the proposed remedies have made a meaningful impact. A key reason may be that DoD cost estimates are formulated using the highly unrealistic assumption that a program’s current baseline characteristics will not change in the future. Using a weather forecasting analogy, the authors demonstrate how a statistical approach may be used to account for these inevitable baseline changes and identify related cost growth trends. These trends are then used to reduce the error in initial acquisition cost estimates by over one third for major defense acquisition programs, representing a more efficient allocation of $6 billion annually
Two-colour single-molecule photoinduced electron transfer fluorescence imaging microscopy of chaperone dynamics
Many proteins are molecular machines, whose function is dependent on multiple conformational changes that are initiated and tightly controlled through biochemical stimuli. Their mechanistic understanding calls for spectroscopy that can probe simultaneously such structural coordinates. Here we present two-colour fluorescence microscopy in combination with photoinduced electron transfer (PET) probes as a method that simultaneously detects two structural coordinates in single protein molecules, one colour per coordinate. This contrasts with the commonly applied resonance energy transfer (FRET) technique that requires two colours per coordinate. We demonstrate the technique by directly and simultaneously observing three critical structural changes within the Hsp90 molecular chaperone machinery. Our results reveal synchronicity of conformational motions at remote sites during ATPase-driven closure of the Hsp90 molecular clamp, providing evidence for a cooperativity mechanism in the chaperone’s catalytic cycle. Single-molecule PET fluorescence microscopy opens up avenues in the multi-dimensional exploration of protein dynamics and allosteric mechanisms
Analysis of a Novel SPS Configuration Enabled by Lunar ISRU
Architectures for space-based solar power using in situ resource utilization (ISRU) of space materials can greatly reduce earth launch mass and can enable geometric capacity growth. These two factors allow the potential for low cost power generation after development of an in-space infrastructure. A collection of extraction and processing methods designed for lunar operation provides for large volumes of low cost solar panels. With abundant panels a novel configuration for solar power satellites (SPS) is possible which avoids many of the challenges of existing designs. The so-called "tin can" SPS has no moving parts. It includes integral thermal radiators. Station-keeping requirements are minimal. Structural integrity is designed-in so that balance of plant mass is minimal. In this work the architecture and infrastructure supporting the tin can SPS is developed to support rapid construction and deployment. Performance estimates for the SPS are provided regarding heat and energy balance, and specific mass requirements
Lunar-sourced GEO Powersats: An Integrated ISRU System
Solar power satellites (powersats) can be built almost entirely from lunar resources. When C-class asteroids are also included as ore bodies a complete powersat can be built through insitu resource utilization (ISRU) given appropriate processing and transportation technology.This article provides an in-depth overview of the technical feasibility and economic viabilityof lunar construction and operations for powersat component construction and delivery togeostationary earth orbit (GEO). Techno-economic analysis suggests a return on investmentin seven years assuming a three percent discount rate. Electrical power collected in GEO andbeamed to terrestrial receivers by the powersats can be sold as baseload power in the wholesale electricity market to generate revenue. This work presents a complete concept of operationsfrom initial rocket launches to regolith harvesting through transport to GEO. Lunarinfrastructure can be constructed of modules to optimize size and weight for launch costs.Future growth can be derived from using ISRU to build additional processing bases. A scale-up in this manner can provide 22% of the world’s energy needs by the end of a 20-year period.This work builds upon previous studies and completes the architectural description ofpredominantly lunar-sourced GEO powersats
Stability of gametocyte-specific Pfs25-mRNA in dried blood spots on filter paper subjected to different storage conditions
Background: Real-time quantitative nucleic acid sequence-based amplification (QT-NASBA) is a sensitive method for detection of sub-microscopic gametocytaemia by measuring gametocyte-specific mRNA. Performing analysis on fresh whole blood samples is often not feasible in remote and resource-poor areas. Convenient methods for sample storage and transport are urgently needed. Methods: Real-time QT-NASBA was performed on whole blood spiked with a dilution series of purified in-vitro cultivated gametocytes. The blood was either freshly processed or spotted on filter papers. Gametocyte detection sensitivity for QT-NASBA was determined and controlled by microscopy. Dried blood spot (DBS) samples were subjected to five different storage conditions and the loss of sensitivity over time was investigated. A formula to approximate the loss of Pfs25-mRNA due to different storage conditions and time was developed. Results: Pfs25-mRNA was measured in time to positivity (TTP) and correlated well with the microscopic counts and the theoretical concentrations of the dilution series. TTP results constantly indicated higher amounts of RNA in filter paper samples extracted after 24 hours than in immediately extracted fresh blood. Among investigated storage conditions freezing at -20 degrees C performed best with 98.7% of the Pfs25-mRNA still detectable at day 28 compared to fresh blood samples. After 92 days, the RNA detection rate was only slightly decreased to 92.9%. Samples stored at 37 degrees C showed most decay with only 64.5% of Pfs25-mRNA detectable after one month. The calculated theoretical detection limit for 24 h-old DBS filter paper samples was 0.0095 (95% CI: 0.0025 to 0.0380) per mu l. Conclusions: The results suggest that the application of DBS filter papers for quantification of Plasmodium falciparum gametocytes with real-time QT-NASBA is practical and recommendable. This method proved sensitive enough for detection of sub-microscopic densities even after prolonged storage. Decay rates can be predicted for different storage conditions as well as durations
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