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See detailQuantifying the shoreline connection of the Stone Age settlements in Southern Karelia (Finland)
Sikk, Kaarel UL; Kriiska, Aivar; Nordqvist, Kerkko et al

Scientific Conference (2018)

The connection between settlement sites and water bodies has been the most prominent characteristic of the Stone Age settlement patterns in North-Eastern Europe. Geologist and archaeologist Constantin ... [more ▼]

The connection between settlement sites and water bodies has been the most prominent characteristic of the Stone Age settlement patterns in North-Eastern Europe. Geologist and archaeologist Constantin Grewingk stated already in 1865 that in the Eastern Baltic region “Stone Age people lived by the sea and rivers”. Although there was no empirical data at that time, the following discoveries confirmed this claim. The connection is so obvious that archaeological sites are effectively used as a proxy data for reconstructing past shorelines that have been changing due to isostatic land uplift and changing hydrological conditions. The goal of current paper is to give a statistical description of the settlements’ position relative to the shoreline. The case study is based on the Stone Age settlement site locations in Southern Karelia, Finland. The region is characterized by several water bodies, including lake Saimaa, as well as several smaller lakes and rivers. A small amount of settlements in the south-eastern part of the study area is also located on the paleoshorelines of the Baltic Sea. The following questions are asked: how many and what kind of Stone Age sites are shoreline-connected? How to statistically describe the distribution of distances from the settlements to the closest shoreline? Because of the abundance of lake shores in the region, it also has to be judged if the settlement pattern was formed by the economical/cultural lifeways of past inhabitants or was it just enforced by the landscape. To answer this question, it is analysed if the distribution of distances to shoreline of Stone Age sites significantly differs from the ones of later periods? [less ▲]

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See detailQuantifying the uncertainty in a hyperelastic soft tissue model with stochastic parameters
Hauseux, Paul UL; Hale, Jack UL; Cotin, Stéphane et al

in Applied Mathematical Modelling (2018), 62

We present a simple open-source semi-intrusive computational method to propagate uncertainties through hyperelastic models of soft tissues. The proposed method is up to two orders of magnitude faster than ... [more ▼]

We present a simple open-source semi-intrusive computational method to propagate uncertainties through hyperelastic models of soft tissues. The proposed method is up to two orders of magnitude faster than the standard Monte Carlo method. The material model of interest can be altered by adjusting few lines of (FEniCS) code. The method is able to (1) provide the user with statistical confidence intervals on quantities of practical interest, such as the displacement of a tumour or target site in an organ; (2) quantify the sensitivity of the response of the organ to the associated parameters of the material model. We exercise the approach on the determination of a confidence interval on the motion of a target in the brain. We also show that for the boundary conditions under consideration five parameters of the Ogden-Holzapfel-like model have negligible influence on the displacement of the target zone compared to the three most influential parameters. The benchmark problems and all associated data are made available as supplementary material. [less ▲]

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See detailQuantifying the Use of stones in the stone age Fireplaces of Estonia
Sikk, Kaarel UL

in Archaeologia Lituana (2017), 17(17), 26-34

Fireplaces and burnt stones related to them are common features found at Stone Age settlement sites. Although information about them is present in archaeological reports and also available in publications ... [more ▼]

Fireplaces and burnt stones related to them are common features found at Stone Age settlement sites. Although information about them is present in archaeological reports and also available in publications, there has been no general research done regarding combustion features specifically. The purpose of this study was to fill the gap of relevant research and to test the hypothesis that the structural features of fireplaces reveal information on the subsistence model of settlements.The study is based on a database of Estonian Stone Age fireplaces, which was compiled by using the available data on all excavated objects. The database includes 167 fireplaces and contains quantifiable data about stones in fireplaces.The analysis of data revealed that the use of stones in fireplaces changed significantly in time. While most of the Mesolithic fire-places contain them, they become scarce in the Neolithic. It can be concluded that the use of stones in fireplaces is related to the economy of settlements and changes within time reflect the changes in general subsistence strategies. Keywords : fireplaces, hearths, quantitative analysis, reuse of data, Mesolithic, Neolithic. [less ▲]

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See detailQuantile-based performance evaluation on CAN
Navet, Nicolas UL

Scientific Conference (2013, November 12)

Early stage timing analysis on CAN traditionally relies on simulation and worst-case response time (WCRT) analysis. Despite recent progresses, it will be shown than the latter technique remains ... [more ▼]

Early stage timing analysis on CAN traditionally relies on simulation and worst-case response time (WCRT) analysis. Despite recent progresses, it will be shown than the latter technique remains pessimistic especially in complex networking architectures with gateways and heterogeneous communication stacks. Indeed, there are many cases of practical interest where no exact WCRT analyses are available, and merely upper bounds on the response times can be derived, on the basis of which unnecessary conservative design choices may be made. Simulation, on the other hand, does not provide any guarantees per se and should only be used along with a rigorous methodology in the context of critical networks. In this presentation, we argue for the use of quantiles of the response time distribution as performance metrics providing an adjustable trade-off between safety and resource usage optimization. We explain how the exact value of the quantile to consider should be chosen wrt the criticality of the frames, and how to calibrate the simulation lengths accordingly. Also, we highlight necessary conditions that must be met (e.g., response times above the quantiles must not be correlated) and how to verify them. [less ▲]

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See detailQuantisierung - 3 Vortraege
Schlichenmaier, Martin UL

Presentation (2010, January)

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See detailQuantität und Qualität deutscher Vokale bei Lernern mit der L1 Russisch
Bilici, Natalia UL

Bachelor/master dissertation (2012)

Die deutsche Sprache hat ein reiches Vokalsystem. Eine Besonderheit dieses Systems ist die Existenz der sogenannten Kurz- und Langvokale, die bedeutungsunterscheidend sind (Miete und Mitte, Höhle und ... [more ▼]

Die deutsche Sprache hat ein reiches Vokalsystem. Eine Besonderheit dieses Systems ist die Existenz der sogenannten Kurz- und Langvokale, die bedeutungsunterscheidend sind (Miete und Mitte, Höhle und Hölle, Staat und Stadt). Diese zwei Gruppen von Vokalen werden unterschiedlich lang und unterschiedlich gespannt ausgesprochen. Solche Qualitäts- und Quantitätsunterschiede sind nicht für alle Sprachen typisch, deswegen stellt der Erwerb der deutschen Vokale eine Herausforderung für viele Lerner dar. Diese Unterschiede machen aber nicht nur den Lernern des Deutschen viel Mühe, sondern auch den Sprachwissenschaftlern, die sich mit dem deutschen Phonemsystem auseinandersetzen. Linguisten, die in diesem Forschungsgebiet tätig sind, diskutieren immer noch über das entscheidende distinktive Merkmal der deutschen Vokale. Ist es die Quantität oder die Qualität? Das Ziel der vorliegenden Arbeit ist, die Frage aus einer anderen Perspektive zu betrachten. Ich werde überprüfen, wie russischsprachige Lerner des Deutschen mit diesen beiden Parametern umgehen. Was erwerben diese Lerner, in deren Muttersprache weder die Länge noch die Gespanntheit der Vokale bedeutungsunterscheidend sind? [less ▲]

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See detailQuantitative analysis of colony morphology in yeast
Ruusuvuori, Pekka; Lin, Jake UL; Shmulevich, Ilya et al

in BioTechniques (2013)

Microorganisms often form multicellular structures,such as biofilms and structured colonies, which can influence the organism’s virulence, drug resistance, and adherence to medical devices. Phenotypic ... [more ▼]

Microorganisms often form multicellular structures,such as biofilms and structured colonies, which can influence the organism’s virulence, drug resistance, and adherence to medical devices. Phenotypic classification of these structures has traditionally relied on qualitative scoring systems that limit detailed phenotypic comparisons between strains. Automated imaging and quantitative analysis have the potential to improve the speed and accuracy of experiments designed to study the genetic and molecular networks underlying different morphological traits. We have developeda platform that uses automated image analysis and pattern recognition to quantify phenotypic signatures of yeast colonies. The strategy enables quantitative analysis of individual colonies, measured at a single time point or over a series of time-lapse images, as well as the classification of distinct colony shapes based on image-derived features. Phenotypic changes in colonymorphology can be expressed achanges in feature space trajectories over time, thereby enabling the visualization and quantitative analysis of morphological development. To facilitate data exploration, results are plotted dynamically through an interactive web application that integrates the raw and processed images across all time points, allowing exploration of the image-based features and principal components associated with morphological development. The web application YIMAA is available at http://yimaa.cs.tut.fi. [less ▲]

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See detailA quantitative analysis of fish consumption and stroke risk.
Bouzan, C.; Cohen, J. T.; Connor, W. E. et al

in American Journal of Preventive Medicine (2005), 29(4), 347-352

Although a rich source of n-3 polyunsaturated fatty acids (PUFAs) that may confer multiple health benefits, some fish contain methyl mercury (MeHg), which may harm the developing fetus. U.S. government ... [more ▼]

Although a rich source of n-3 polyunsaturated fatty acids (PUFAs) that may confer multiple health benefits, some fish contain methyl mercury (MeHg), which may harm the developing fetus. U.S. government recommendations for women of childbearing age are to modify consumption of high-MeHg fish to reduce MeHg exposure, while recommendations encourage fish consumption among the general population because of the nutritional benefits. The Harvard Center for Risk Analysis convened an expert panel (see acknowledgements) to quantify the net impact of resulting hypothetical changes in fish consumption across the population. This paper estimates the impact of fish consumption on stroke risk. Other papers quantify coronary heart disease mortality risk and the impacts of both prenatal MeHg exposure and maternal intake of n-3 PUFAs on cognitive development. This analysis identified articles in a recent qualitative literature review that are appropriate for the development of a dose-response relationship between fish consumption and stroke risk. Studies had to satisfy quality criteria, quantify fish intake, and report the precision of the relative risk estimates. The analysis combined the relative risk results, weighting each proportionately to its precision. Six studies were identified as appropriate for inclusion in this analysis, including five prospective cohort studies and one case-control study (total of 24 exposure groups). Our analysis indicates that any fish consumption confers substantial relative risk reduction compared to no fish consumption (12% for the linear model), with the possibility that additional consumption confers incremental benefits (central estimate of 2.0% per serving per week). [less ▲]

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See detailA Quantitative Analysis of Security, Anonymity and Scalability for the Lightning Network
Tikhomirov, Sergei UL; Moreno-Sanchez, Pedro; Maffei, Matteo

in Proceedings of 2020 IEEE European Symposium on Security and Privacy (EuroS&P) (2020, September)

Payment channel networks have been introduced to mitigate the scalability issues inherent to permissionless decentralized cryptocurrencies such as Bitcoin. Launched in 2018, the Lightning Network (LN) has ... [more ▼]

Payment channel networks have been introduced to mitigate the scalability issues inherent to permissionless decentralized cryptocurrencies such as Bitcoin. Launched in 2018, the Lightning Network (LN) has been gaining popularity and consists today of more than 5000 nodes and 30000 payment channels that jointly hold 895 bitcoins (7.6M USD as of February 2020). This adoption has motivated research from both academia and industry. Payment channels suffer from security vulnerabilities, such as the wormhole attack, anonymity issues, and scalability limitations related to the upper bound on the number of concurrent payments per channel, which have been pointed out by the scientific community but never quantitatively analyzed. In this work, we first analyze the proneness of the LN to the wormhole attack and attacks against anonymity. We observe that an adversary needs to control only 2% of LN nodes to learn sensitive payment information (e.g., sender, receiver and payment amount) or to carry out the wormhole attack. Second, we study the management of concurrent payments in the LN and quantify its negative effect on scalability. We observe that for micropayments, the forwarding capability of up to 50% of channels is restricted to a value smaller than the overall channel capacity. This phenomenon not only hinders scalability but also opens the door for DoS attacks: We estimate that a network-wide DoS attack costs within 1.5M USD, while isolating the biggest community from the rest of the network costs only 225k USD. Our findings should prompt the LN community to consider the security, privacy and scalability issues of the network studied in this work when educating users about path selection algorithms, as well as to adopt multi-hop payment protocols that provide stronger security, privacy and scalability guarantees. [less ▲]

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See detailQuantitative analysis of the self-assembly strategies of intermediate filaments from tetrameric vimentin
Czeizler, Eugen; Mizera, Andrzej UL; Czeizler, Elena et al

in IEEE/ACM Transactions on Computational Biology and Bioinformatics (2012), 9(3), 885-898

Detailed reference viewed: 74 (2 UL)
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See detailA quantitative approach to catabolite repression in Escherichia coli.
Bettenbrock, Katja; Fischer, Sophia; Kremling, Andreas et al

in Journal of Biological Chemistry (2006), 281(5), 2578-84

A dynamic mathematical model was developed to describe the uptake of various carbohydrates (glucose, lactose, glycerol, sucrose, and galactose) in Escherichia coli. For validation a number of isogenic ... [more ▼]

A dynamic mathematical model was developed to describe the uptake of various carbohydrates (glucose, lactose, glycerol, sucrose, and galactose) in Escherichia coli. For validation a number of isogenic strains with defined mutations were used. By considering metabolic reactions as well as signal transduction processes influencing the relevant pathways, we were able to describe quantitatively the phenomenon of catabolite repression in E. coli. We verified model predictions by measuring time courses of several extra- and intracellular components such as glycolytic intermediates, EII-ACrr phosphorylation level, both LacZ and PtsG concentrations, and total cAMP concentrations under various growth conditions. The entire data base consists of 18 experiments performed with nine different strains. The model describes the expression of 17 key enzymes, 38 enzymatic reactions, and the dynamic behavior of more than 50 metabolites. The different phenomena affecting the phosphorylation level of EIIACrr, the key regulation molecule for inducer exclusion and catabolite repression in enteric bacteria, can now be explained quantitatively. [less ▲]

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See detailA quantitative approach to study indirect effects among disease proteins in the human protein interaction network
Nguyen, Thanh-Phuong UL; Jordán, Ferenc

in BMC Systems Biology (2010), 4(1), 103

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See detailQuantitative Assignment of Reaction Directionality in a Multicompartmental Human Metabolic Reconstruction
Haraldsdottir, Hulda UL; Thiele, Ines UL; Fleming, Ronan MT UL

in Biophysical Journal (2012), 102(8), 17031711

Reaction directionality is a key constraint in the modeling of genome-scale metabolic networks. We thermodynamically constrained reaction directionality in a multicompartmental genome-scale model of human ... [more ▼]

Reaction directionality is a key constraint in the modeling of genome-scale metabolic networks. We thermodynamically constrained reaction directionality in a multicompartmental genome-scale model of human metabolism, Recon 1, by calculating, in vivo, standard transformed reaction Gibbs energy as a function of compartment-specific pH, electrical potential, and ionic strength. We show that compartmental pH is an important determinant of thermodynamically determined reaction directionality. The effects of pH on transport reaction thermodynamics are only seen to their full extent when metabolites are represented as pseudoisomer groups of multiple protonated species. We accurately predict the irreversibility of 387 reactions, with detailed propagation of uncertainty in input data, and manually curate the literature to resolve conflicting directionality assignments. In at least half of all cases, a prediction of a reversible reaction directionality is due to the paucity of compartment-specific quantitative metabolomic data, with remaining cases due to uncertainty in estimation of standard reaction Gibbs energy. This study points to the pressing need for 1), quantitative metabolomic data, and 2), experimental measurement of thermochemical properties for human metabolites. [less ▲]

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See detailQuantitative assignment of reaction directionality in constraint-based models of metabolism: application to Escherichia coli.
Fleming, Ronan MT UL; Thiele, Ines UL; Nasheuer, H. P.

in Biophysical Chemistry (2009), 145(2-3), 47-56

Constraint-based modeling is an approach for quantitative prediction of net reaction flux in genome-scale biochemical networks. In vivo, the second law of thermodynamics requires that net macroscopic flux ... [more ▼]

Constraint-based modeling is an approach for quantitative prediction of net reaction flux in genome-scale biochemical networks. In vivo, the second law of thermodynamics requires that net macroscopic flux be forward, when the transformed reaction Gibbs energy is negative. We calculate the latter by using (i) group contribution estimates of metabolite species Gibbs energy, combined with (ii) experimentally measured equilibrium constants. In an application to a genome-scale stoichiometric model of Escherichia coli metabolism, iAF1260, we demonstrate that quantitative prediction of reaction directionality is increased in scope and accuracy by integration of both data sources, transformed appropriately to in vivo pH, temperature and ionic strength. Comparison of quantitative versus qualitative assignment of reaction directionality in iAF1260, assuming an accommodating reactant concentration range of 0.02-20mM, revealed that quantitative assignment leads to a low false positive, but high false negative, prediction of effectively irreversible reactions. The latter is partly due to the uncertainty associated with group contribution estimates. We also uncovered evidence that the high intracellular concentration of glutamate in E. coli may be essential to direct otherwise thermodynamically unfavorable essential reactions, such as the leucine transaminase reaction, in an anabolic direction. [less ▲]

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See detailQuantitative Breuer-Major theorems
Nourdin, Ivan UL; Peccati, Giovanni UL; Podolskij, Mark

in Stochastic Processes & Their Applications (2011), 121(4), 793--812

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See detailQuantitative C1-estimates by Bismut formulae
Cheng, Li Juan UL; Thalmaier, Anton UL; Thompson, James UL

in Journal of Mathematical Analysis and Applications (2018), 465(2), 803-813

For a C2 function u and an elliptic operator L, we prove a quantitative estimate for the derivative du in terms of local bounds on u and Lu. An integral version of this estimate is then used to derive a ... [more ▼]

For a C2 function u and an elliptic operator L, we prove a quantitative estimate for the derivative du in terms of local bounds on u and Lu. An integral version of this estimate is then used to derive a condition for the zero-mean value property of Δu. An extension to differential forms is also given. Our approach is probabilistic and could easily be adapted to other settings. [less ▲]

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See detailA quantitative central limit theorem for linear statistics of random matrix eigenvalues
Döbler, Christian UL; Stolz, Michael

in Journal of Theoretical Probability (2014)

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See detailQuantitative CLTs for symmetric U-statistics using contractions
Döbler, Christian UL; Peccati, Giovanni UL

in Electronic Journal of Probability (2019)

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See detailQuantitative CLTs on a Gaussian space: a survey of recent developments
Peccati, Giovanni UL

in ESAIM: Proceedings and Surveys (2014), 44

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See detailQuantitative de Jong theorems in any dimension
Döbler, Christian UL; Peccati, Giovanni UL

in Electronic Journal of Probability (2017), 22

Detailed reference viewed: 227 (25 UL)