524 research outputs found

    HELAS Local Helioseismology Activities

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    The main goals of the HELAS local helioseismology network activity are to consolidate this field of research in Europe, to organise scientific workshops, and to facilitate the distribution of observations and data analysis software. Most of this is currently accomplished via a dedicated website at http://www.mps.mpg.de/projects/seismo/NA4/ . In this paper we list the outreach material, observational data, analysis tools and modelling tools currently available from the website and describe the focus of the scientific workshops and their proceedings.Comment: 14 pages, 5 figure

    Transitioning Island Energy Systems - Local Conditions, Development Phases and Renewable Energy Integration

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    Islands typically have sensitive energy systems depending on natural surroundings, but innovative technologies and the exploitation of renewable energy (RE) sources present opportunities like self-sufficiency, but also challenges, such as grid instability. Samsø, Orkney, and Madeira are in the transition to increase the RE share towards 100%—however, this is addressed in different ways depending on the local conditions and current development phases in the transition. Scenarios focusing on the short-term introduction of new technologies in the energy systems are presented, where the electricity sector is coupled with the other energy sectors. Here, both smart grid and sector-integrating solutions form an important part in the next 5–15 years. The scenarios are analyzed using the modeling tool EnergyPLAN, enabling a comparison of today’s reference scenarios with 2030 scenarios of higher RE share. By including three islands across Europe, different locations, development stages, and interconnection levels are analyzed. The analyses suggest that the various smart grid solutions play an important part in the transition; however, local conditions, sector integration, and balancing technologies even more so. Overall, the suggestions complement each other and pave the way to reach 100% RE integration for both islands and, potentially, other similar regions

    NeRFtrinsic Four: An End-To-End Trainable NeRF Jointly Optimizing Diverse Intrinsic and Extrinsic Camera Parameters

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    Novel view synthesis using neural radiance fields (NeRF) is the state-of-the-art technique for generating high-quality images from novel viewpoints. Existing methods require a priori knowledge about extrinsic and intrinsic camera parameters. This limits their applicability to synthetic scenes, or real-world scenarios with the necessity of a preprocessing step. Current research on the joint optimization of camera parameters and NeRF focuses on refining noisy extrinsic camera parameters and often relies on the preprocessing of intrinsic camera parameters. Further approaches are limited to cover only one single camera intrinsic. To address these limitations, we propose a novel end-to-end trainable approach called NeRFtrinsic Four. We utilize Gaussian Fourier features to estimate extrinsic camera parameters and dynamically predict varying intrinsic camera parameters through the supervision of the projection error. Our approach outperforms existing joint optimization methods on LLFF and BLEFF. In addition to these existing datasets, we introduce a new dataset called iFF with varying intrinsic camera parameters. NeRFtrinsic Four is a step forward in joint optimization NeRF-based view synthesis and enables more realistic and flexible rendering in real-world scenarios with varying camera parameters

    On the Mixed Gas Behavior of Organosilica Membranes Fabricated by Plasma-Enhanced Chemical Vapor Deposition (PECVD)

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    Selective, nanometer-thin organosilica layers created by plasma-enhanced chemical vapor deposition (PECVD) exhibit selective gas permeation behavior. Despite their promising pure gas performance, published data with regard to mixed gas behavior are still severely lacking. This study endeavors to close this gap by investigating the pure and mixed gas behavior depending on temperatures from 0 °C to 60 °C for four gases (helium, methane, carbon dioxide, and nitrogen) and water vapor. For the two permanent gases, helium and methane, the studied organosilica membrane shows a substantial increase in selectivity from αHe/CH4 = 9 at 0 °C to αHe/CH4 = 40 at 60 °C for pure as well as mixed gases with helium permeance of up to 300 GPU. In contrast, a condensable gas such as CO2 leads to a decrease in selectivity and an increase in permeance compared to its pure gas performance. When water vapor is present in the feed gas, the organosilica membrane shows even stronger deviations from pure gas behavior with a permeance loss of about 60 % accompanied by an increase in ideal selectivity αHe/CO2 from 8 to 13. All in all, the studied organosilica membrane shows very promising results for mixed gases. Especially for elevated temperatures, there is a high potential for separation by size exclusion

    Therapeutic Targeting of TGFβ Ligands in Glioblastoma Using Novel Antisense Oligonucleotides Reduces the Growth of Experimental Gliomas

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    PURPOSE Transforming growth factor (TGF)-β is expressed at high levels by glioma cells and contributes to the malignant phenotype of glioblastoma. However, its therapeutic targeting remains challenging. Here, we examined an alternative therapeutic approach of TGFβ inhibition using two novel phosphorothioate-locked nucleic acid (LNA)-modified antisense oligonucleotide gapmers, ISTH1047 and ISTH0047, which specifically target TGFβ and TGFβ. EXPERIMENTAL DESIGN We characterized the effects of ISTH1047 and ISTH0047 on TGFβ expression, downstream signaling and growth of human LN-308, LN-229, and ZH-161 cells as well as murine SMA-560 glioma cells . Furthermore, we assessed their target inhibition and effects on survival in orthotopic xenogeneic and syngeneic rodent glioma models . RESULTS Both antisense oligonucleotides specifically silenced their corresponding target and abrogated SMAD2 phosphorylation in several glioma cell lines. Moreover, inhibition of TGFβ or TGFβ expression by ISTH1047 or ISTH0047 reduced the migration and invasiveness of LN-308 and SMA-560 glioma cells. Systemic antisense oligonucleotide administration to glioma-bearing mice suppressed or mRNA expression as well as the expression of the downstream target in orthotopic gliomas. Glioma-bearing mice had significantly prolonged survival upon systemic treatment with ISTH1047 or ISTH0047, which was associated with a reduction of intratumoral SMAD2 phosphorylation and, in a fully immunocompetent model, with increased immune cell infiltration. CONCLUSIONS Targeting TGFβ expression with the novel LNA antisense oligonucleotides ISTH1047 or ISTH0047 results in strong antiglioma activity and , which may represent a promising approach to be examined in human patients with glioma

    DynaMoN: Motion-Aware Fast And Robust Camera Localization for Dynamic NeRF

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    Dynamic reconstruction with neural radiance fields (NeRF) requires accurate camera poses. These are often hard to retrieve with existing structure-from-motion (SfM) pipelines as both camera and scene content can change. We propose DynaMoN that leverages simultaneous localization and mapping (SLAM) jointly with motion masking to handle dynamic scene content. Our robust SLAM-based tracking module significantly accelerates the training process of the dynamic NeRF while improving the quality of synthesized views at the same time. Extensive experimental validation on TUM RGB-D, BONN RGB-D Dynamic and the DyCheck's iPhone dataset, three real-world datasets, shows the advantages of DynaMoN both for camera pose estimation and novel view synthesis.Comment: 6 pages, 4 figure

    Antibiotic prophylaxis in transurethral resection of bladder tumours: study protocol for a systematic review and meta-analysis

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    The necessity of antibiotic prophylaxis for postoperative urinary tract infections (UTIs) after transurethral resection of bladder tumours is controversial. This potentially leads to the overuse of antibiotic prophylaxis and rising antimicrobial resistance rates. The objective of this systematic review and meta-analysis is to compare the impact of different antimicrobial prophylaxis schemes versus placebo on the prevention of postoperative UTI and asymptomatic bacteriuria.; We designed and registered a study protocol for a systematic review and meta-analysis of randomized controlled trials and non-randomized (e.g. cohort, case-control) studies examining any form of antibiotic prophylaxis in patients with transurethral resection of bladder tumours. Literature searches will be conducted in several electronic databases (from inception onwards), including MEDLINE (Ovid), EMBASE (Ovid), and the Cochrane Central Register of Controlled Trials (CENTRAL). Grey literature will be identified through searching conference abstracts. The primary outcome will be postoperative urinary tract infections. The secondary outcome will be asymptomatic bacteriuria. Two reviewers will independently screen all citations, full-text articles, and abstract data. Potential conflicts will be resolved through discussion. The study methodological quality (or bias) will be appraised using appropriate tools (e.g. Risk of Bias 2.0 tool and Newcastle-Ottawa Scale). If feasible, we will conduct random-effects meta-analysis of outcome data. Additional analyses will be conducted to explore the potential sources of heterogeneity (e.g. study design, publication year, the setting of the study, and antibiotics regimen). We will also search, identify, and discuss potential risk factors for urinary tract infections following transurethral resection of bladder tumours. This may serve as basis for a scoping review.; In times of rising antimicrobial resistance rates, sound evidence on the necessity of antibiotic prophylaxis is essential for implementation into guideline recommendations and for decision-making in clinical practice

    Experimental Analysis of the Fuel Flexibility of a Jet-stabilized Micro Gas Turbine Combustor Designed for Low Calorific Gases

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    Fuel flexible burners are an important concept to aid in the advancement and implementation of renewable energy sources into existing infrastructure. As focus shifts from conventional to renewable fuel sources, designing gas turbines which meet both the technical and load requirements for fluctuating fuel compositions and heating values is imperative. The present work aims to study the stability and fuel flexibility of a two-stage burner, consisting of a jet-stabilized main stage and a swirl-stabilized pilot stage. Various fuel compositions, consisting of natural gas, hydrogen, carbon monoxide, carbon dioxide and nitrogen, with lower heating values ranging from 7MJ/kg to 49MJ/kg at an air preheat temperature of 873K were tested. Additionally, differing power loads (60kW to 100kW) and air-fuel equivalence ratio ranges (1.5-3.6) were examined. This study utilized OH* chemiluminescence measurements in conjunction with exhaust gas analysis of carbon monoxide and nitrogen oxide levels to assess the operation and reliability of the burner. Moreover, the experimental results are supported by steady state computational fluid dynamics simulations to provide explanation of the flame flow field characteristics and kinetics. The results indicate flame stability and low emissions levels for the majority of fuel compositions and thermal loads tested, therefore signifying high fuel flexibility of the burner. Additionally, optimal combustor operating points, which display emissions levels below the proposed German legal limits (German Federal Ministry for the Environment, 2016), were determined. Furthermore, the computational fluid dynamics simulation results indicate a good match to the experimental results, providing insight into the burner flow field characteristics and kinetics

    A Supposedly Developed Country’s Response to a Healthcare Crisis: Lessons from the COVID-19 Pandemic for Future National Emergencies

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    The world has just suffered through a pandemic that was responsible for the 7 million deaths. The expectation prior to this devastation would have been those countries like the United States, which are considered “developed”, would have been prepared and able to ameliorate the effects of such a catastrophic event. However, this was not the case. In fact, many countries not necessarily considered underdeveloped or undeveloped weathered this crisis by mounting a much more organized response. This chapter will review the history of similar episodic epidemics, the failures that led to over a million deaths in the United States, and most importantly what is necessary to a similar event in the future to be dealt preventing the devastation that did occur in a most “developed” country like the United States. These lesions and their possible extrapolation worldwide, hoping will prevent a recurrence of the devastation we have recently experienced in the United States
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