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See detailAn Evaluation of New Estimates from GPS, GRACE and Load Models compared to SLR
Lavalee, D.; Moore, P.; Clarke, Peter J. et al

in Geophysical Research Letters (2010), (37), 5-6

Changes in J2, resulting from past and present changes in Earth’s climate, are traditionally observed by Satellite Laser ranging (SLR). Assuming an elastic Earth, it is possible to infer changes in J2 ... [more ▼]

Changes in J2, resulting from past and present changes in Earth’s climate, are traditionally observed by Satellite Laser ranging (SLR). Assuming an elastic Earth, it is possible to infer changes in J2 from changes in Earth’s shape observed by GPS. We compare estimates of non‐secular J2 changes from GPS, SLR, GRACE, and a load model. The GPS and SLR annual signals agree but are different (16%) to the load model. Subtraction of the load model removes the annual variation from GPS, SLR, and GRACE, and the semi‐annual variation in GPS. The GPS and SLR long‐term signals are highly correlated, but GPS is better correlated with the loading model. Subtraction of the load model removes the 1998 anomaly from the GPS J2 series but not completely from the SLR J2 series, suggesting that the SLR anomaly may not be entirely due to mass re‐distribution as has been presumed. [less ▲]

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See detailEvaluation of PGM2007A by comparison with globally and locally estimated gravity solutions from CHAMP
Weigelt, Matthias UL; Sneeuw, N.; Keller, W.

in Newton's Bulletin (2009), 4

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See detailEvaluation of plasma membrane calcium/calmodulin-dependent ATPase isoform 4 as a potential target for fertility control.
Cartwright, Elizabeth J.; Neyses, Ludwig UL

in Handbook of experimental pharmacology (2010), (198), 79-95

The array of contraceptives currently available is clearly inadequate and does not meet consumer demands since it is estimated that up to a quarter of all pregnancies worldwide are unintended. There is ... [more ▼]

The array of contraceptives currently available is clearly inadequate and does not meet consumer demands since it is estimated that up to a quarter of all pregnancies worldwide are unintended. There is, therefore, an overwhelming global need to develop new effective, safe, ideally non-hormonal contraceptives for both male and female use. The contraceptive field, unlike other areas such as cancer, has a dearth of new targets. We have addressed this issue and propose that isoform 4 of the plasma membrane calcium ATPase is a potentially exciting novel target for fertility control. The plasma membrane calcium ATPase is a ubiquitously expressed calcium pump whose primary function in the majority of cells is to extrude calcium to the extracellular milieu. Two isoforms of this gene family, PMCA1 and PMCA4, are expressed in spermatozoa, with PMCA4 being the predominant isoform. Although this gene is ubiquitously expressed, its function is highly tissue-specific. Genetic deletion of PMCA4, in PMCA4 knockout mice, led to 100% infertility specifically in the male mutant mice due to a selective defect in sperm motility. It is important to note that the gene deletion did not affect normal mating characteristics in these mice. This phenotype was mimicked in wild-type sperm treated with the non-specific PMCA inhibitor 5-(and 6-) carboxyeosin diacetate succinimidyl ester; a proof-of-principle that inhibition of PMCA4 has potential importance in the control of fertility. This review outlines the potential for PMCA4 to be a novel target for fertility control by acting to inhibit sperm motility. It will outline the characteristics that make this target drugable and will describe methodologies to identify and validate novel inhibitors of this target. [less ▲]

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See detailEvaluation of potassium chloride emissions applying the Discrete Particle Method (DPM)
Peters, Bernhard UL; Smula, Joanna UL

in Computers & Chemical Engineering (2011)

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See detailEvaluation of Presumably Disease Causing SCN1A Variants in a Cohort of Common Epilepsy Syndromes
Lal, Dennis; Reinthaler, Eva; Dejanovic et al

in PLoS ONE (2016)

Objective The SCN1A gene, coding for the voltage-gated Na+ channel alpha subunit NaV1.1, is the clinically most relevant epilepsy gene. With the advent of high-throughput next-generation sequencing ... [more ▼]

Objective The SCN1A gene, coding for the voltage-gated Na+ channel alpha subunit NaV1.1, is the clinically most relevant epilepsy gene. With the advent of high-throughput next-generation sequencing, clinical laboratories are generating an ever-increasing catalogue of SCN1A variants. Variants are more likely to be classified as pathogenic if they have already been identified previously in a patient with epilepsy. Here, we critically re-evaluate the pathogenicity of this class of variants in a cohort of patients with common epilepsy syndromes and subsequently ask whether a significant fraction of benign variants have been misclassified as pathogenic. Methods We screened a discovery cohort of 448 patients with a broad range of common genetic epilepsies and 734 controls for previously reported SCN1A mutations that were assumed to be disease causing. We re-evaluated the evidence for pathogenicity of the identified variants using in silico predictions, segregation, original reports, available functional data and assessment of allele frequencies in healthy individuals as well as in a follow up cohort of 777 patients. Results and Interpretation We identified 8 known missense mutations, previously reported as pathogenic, in a total of 17 unrelated epilepsy patients (17/448; 3.80%). Our re-evaluation indicates that 7 out of these 8 variants (p.R27T; p.R28C; p.R542Q; p.R604H; p.T1250M; p.E1308D; p.R1928G; NP_001159435.1) are not pathogenic. Only the p.T1174S mutation may be considered as a genetic risk factor for epilepsy of small effect size based on the enrichment in patients (P = 6.60 x 10−4; OR = 0.32, fishers exact test), previous functional studies but incomplete penetrance. Thus, incorporation of previous studies in genetic counseling of SCN1A sequencing results is challenging and may produce incorrect conclusions. [less ▲]

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See detailEvaluation of RDS/Peripherin and ROM1 as candidate genes in generalised progressive retinal atrophy and exclusion of digenic inheritance
Runte, Maren UL; Dekomien, Gabriele; Epplen, Jörg T

in Animal Genetics (2000), 31(3), 223-227

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See detailAn evaluation of real-time troposphere estimation based on GNSS Precise Point Positioning
Ding, Wenwu; Teferle, Felix Norman UL; Kazmierski, Kamil et al

in Journal of Geophysical Research: Atmospheres (2017), 122(5), 2779--2790

It is anticipated that the performance of real-time (RT) GNSS meteorology can be further improved by incorporating observations from multiple Global Navigation Satellite System (GNSS), including GPS ... [more ▼]

It is anticipated that the performance of real-time (RT) GNSS meteorology can be further improved by incorporating observations from multiple Global Navigation Satellite System (GNSS), including GPS, GLONASS, Galileo, and BeiDou. In this paper, an operational RT system for extracting zenith troposphere delay (ZTD) using a modified version of the Precise Point Positioning With Integer and Zero-difference Ambiguity Resolution Demonstrator (PPP-WIZARD) was established. GNSS, including GPS, GLONASS, and Galileo, observation streams were processed using RT Precise Point Positioning (PPP) strategy based on RT satellite orbit/clock products from the Centre National d'Etudes Spatiales. An experiment covering 30 days was conducted, in which the observation streams of 20 globally distributed stations were processed. The initialization time and accuracy of the RT troposphere results using single-system and multisystem observations were evaluated. The effect of PPP ambiguity resolution was also evaluated. Results reveal that RT troposphere estimates based on single-system observations can both be applied in weather nowcasting, in which the GPS-only solution is better than the GLONASS-only solution. The performance can also be improved by PPP ambiguity resolution and utilizing GNSS observations. Specifically, we notice that ambiguity resolution is more effective in improving the accuracy of ZTD, whereas the initialization process can be better accelerated by GNSS observations. Combining all techniques, the RT troposphere results with an average accuracy of about 8 mm in ZTD can be achieved after an initialization process of approximately 8.5 min, which demonstrates superior results for applying GNSS observations and ambiguity resolution for RT meteorological applications. [less ▲]

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See detailAn Evaluation of Real-Time Zenith Total Delay Estimates
Ahmed, Furqan UL; Teferle, Felix Norman UL; Bingley, Richard

Poster (2012, December)

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See detailEvaluation of Resource-based App Repackaging Detection in Android
Gadyatskaya, Olga UL; Lezza, A.-L.; Zhauniarovich, Y.

in Proc. of NordSec (2016)

Android app repackaging threatens the health of application markets, as repackaged apps, besides stealing revenue for honest developers, are also a source of malware distribution. Techniques that rely on ... [more ▼]

Android app repackaging threatens the health of application markets, as repackaged apps, besides stealing revenue for honest developers, are also a source of malware distribution. Techniques that rely on visual similarity of Android apps recently emerged as a way to tackle the repackaging detection problem, as code-based detection techniques often fail in terms of effi ciency, and e ffectiveness when obfuscation is applied [19,21]. Among such techniques, the resource-based repackaging detection approach that compares sets of files included in apks has arguably the best performance [20,17,10]. Yet, this approach has not been previously validated on a dataset of repackaged apps. In this paper we report on our evaluation of the approach, and present substantial improvements to it. Our experiments show that the state-of-art tools applying this technique rely on too restrictive thresholds. Indeed, we demonstrate that a very low proportion of identical resource files in two apps is a reliable evidence for repackaging. Furthermore, we have shown that the Overlap similarity score performs better than the Jaccard similarity coe fficient used in previous works. By applying machine learning techniques, we give evidence that considering separately the included resource fi le types signi cantly improves the detection accuracy of the method. Experimenting with a balanced dataset of more than 2700 app pairs, we show that with our enhancements it is possible to achieve the F-measure of 0.9919. [less ▲]

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See detailEvaluation of reverse osmosis drinking water treatment of riverbank filtrate using bioanalytical tools and non-target screening
Albergamo, Vittorio; Escher, Beate I.; Schymanski, Emma UL et al

in Environmental Science: Water Research & Technology (2020), 6(1), 103--116

Stand-alone reverse osmosis (RO) has been proposed to produce high-quality drinking water from raw riverbank filtrate impacted by anthropogenic activities. To evaluate RO efficacy in removing organic ... [more ▼]

Stand-alone reverse osmosis (RO) has been proposed to produce high-quality drinking water from raw riverbank filtrate impacted by anthropogenic activities. To evaluate RO efficacy in removing organic micropollutants, biological analyses were combined with non-target screening using high-resolution mass spectrometry and open cheminformatics tools. The bank filtrate induced xenobiotic metabolism mediated by the aryl hydrocarbon receptor AhR, adaptive stress response mediated by the transcription factor Nrf2 and genotoxicity in the Ames-fluctuation test. These effects were absent in the RO permeate (product water), indicating the removal of bioactive micropollutants by RO membranes. In the water samples, 49 potentially toxic compounds were tentatively identified with the in silico fragmentation tool MetFrag using the US Environmental Protection Agency CompTox Chemicals Dashboard database. 5 compounds were confirmed with reference standards and 16 were tentatively identified with high confidence based on similarities to accurate mass spectra in open libraries. The bioactivity data of the confirmed chemicals indicated that 2,6-dichlorobenzamide and bentazone in water samples can contribute to the activation of AhR and oxidative stress response, respectively. The bioactivity data of 7 compounds tentatively identified with high confidence indicated that these structures can contribute to the induction of such effects. This study showed that riverbank filtration followed by RO could produce drinking water free of the investigated toxic effects. [less ▲]

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See detailEvaluation of school tasks in the light of sustainability education: Textbook research in science education in Luxembourgish primary schools
Andersen, Katja Natalie UL

in Environmental Education Research (2018), 24(9), 1301-1319

This article describes a research project that aimed to classify different types of sustainability-related school tasks in terms of two central approaches in primary school education: action-based and ... [more ▼]

This article describes a research project that aimed to classify different types of sustainability-related school tasks in terms of two central approaches in primary school education: action-based and task-based learning. Using a textbook analysis approach, the article clarifies implicit and explicit forms of sustainability education in school tasks in Luxembourgish science textbooks for Grades 1 to 6. The study uses a two-step analysis: first, scanning textbooks on content relating to sustainability; and, second, evaluating the teaching practices associated with this content apparent in the textbooks. Step one identifies the school tasks in which sustainability content is implicitly or explicitly addressed while step two analyzes which forms of action-based and task-based learning occur in these sustainability-related school tasks. Based on the results two claims can be made: first, that there is very little sustainability-related content in Luxembourgish primary science textbooks, and those topics raised mostly relate to sustainability only indirectly; secondly, action-based and task-based learning are undervalued in the context of sustainability-related school tasks; neither of the two was commonly found in school tasks in sustainability education. [less ▲]

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See detailEvaluation of Stratified Condensation Models for a slightly inclined tube unsing ATHELT Code
Zhang, Yu; Moonesi Shabestary, Amir Hossein; Bieberle, Andre et al

in NURETH-18 (2019)

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See detailAn Evaluation of the Accuracy of Real-Time Zenith Total Delay Estimates
Ahmed, Furqan UL; Teferle, Felix Norman UL; Bingley, Richard et al

Scientific Conference (2013, April 12)

The continuous evolution of Global Navigation Satellite Systems (GNSS) meteorology has lead to an increased use of associated observations for operational meteorology worldwide. In order to enhance short ... [more ▼]

The continuous evolution of Global Navigation Satellite Systems (GNSS) meteorology has lead to an increased use of associated observations for operational meteorology worldwide. In order to enhance short-term weather forecasts meteorological institutions use modern low-latency Numerical Weather Prediction (NWP) models which assimilate GNSS-derived Zenith Total Delay (ZTD) estimates. For such NWP models a number of GNSS processing strategies allow the provision of these ZTDs with the required accuracy (up to a few millimetres) and latency (hourly). However, meteorological now-casting applications, e.g. for storm tracking, require higher update rates for the ZTDs of 10 or even 5 min, which can be achieved, but only at a loss in accuracy. Using the IGS Real-Time Service orbit and clock products together with an appropriate GNSS software, it is possible to estimate the ZTDs in real-time. Available software packages either use GNSS processing strategies based on differenced or un-differenced observations, such as Precise Point Positioning (PPP). While PPP has clear advantages for efficiently processing data streams from large GNSS networks this strategy is more affected by inaccuracies in the real-time products than when using differenced observations. On the other hand, recent advances in PPP integer ambiguity resolution nowadays provide this strategy with the benefits of ambiguity-fixed solutions. In this study, we present an evaluation of the accuracy of real-time ZTD estimates obtained from several GNSS processing systems through comparison to those obtained from a near real-time and a post-processing system. [less ▲]

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See detailEvaluation of the bridge Champangshiel by using static assessment methods
Scherbaum, Frank; Mahowald, Jean; Waldmann, Danièle UL

in KIT Scientific Publishing, No. 026a, p. 323-329 (2012, July)

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See detailEvaluation of the EGM2008 by Comparison with Global and Local Gravity Solutions from CHAMP
Weigelt, Matthias UL; Sneeuw, N.; Keller, W.

in Mertikas, S. P. (Ed.) Gravity, Geoid and Earth Observation (2010, June)

Detailed reference viewed: 64 (0 UL)