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See detailQuantification of surface ZnSe in Cu2ZnSnSe4-based solar cells by analysis of the spectral response
Colombara, Diego UL; Robert, Erika UL; Crossay, Alexandre UL et al

in Solar Energy Materials & Solar Cells (2014), 123

Absorber layers consisting of Cu2ZnSnSe4 (CZTSe) and surface ZnSe in variable ratios were prepared by selenization of electroplated Cu/Sn/Zn precursors and completed into full devices with up to 5.6 ... [more ▼]

Absorber layers consisting of Cu2ZnSnSe4 (CZTSe) and surface ZnSe in variable ratios were prepared by selenization of electroplated Cu/Sn/Zn precursors and completed into full devices with up to 5.6 % power conversion efficiency. The loss of short circuit current density for samples with increasing ZnSe content is consistent with an overall reduction of spectral response, pointing to a ZnSe current blocking behavior. A feature in the spectral response centered around 3 eV was identified and attributed to light absorption by ZnSe. A model is proposed to account for additional collection of the carriers generated underneath ZnSe capable of diffusing across to the space charge region. The model satisfactorily reproduces the shape of the spectral response and the estimated ZnSe surface coverage is in good qualitative agreement with analysis of the Raman spectral mapping. The model emphasizes the importance of the ZnSe morphology on the spectral response, and its consequences on the solar cell device performance. [less ▲]

Detailed reference viewed: 483 (10 UL)
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See detailQuantification of wild-type mitochondrial DNA and its 4.8-kb deletion in rat organs.
Filser, N.; Margue, Christiane UL; Richter, C.

in Biochemical and biophysical research communications (1997), 233(1), 102-7

Oxidative damage to mitochondrial DNA (mtDNA) is considered a major contributor in aging. An age-dependent increase of oxidative damage and of the quantity of partially deleted mtDNA was reported for ... [more ▼]

Oxidative damage to mitochondrial DNA (mtDNA) is considered a major contributor in aging. An age-dependent increase of oxidative damage and of the quantity of partially deleted mtDNA was reported for several rat and human organs. Here, a systematic investigation of ten different tissues and organs of 20-months-old rats was performed. The amount of mtDNA and age-dependent 4.8 kb deletion (delta mtDNA4834) was determined by competitive polymerase chain reaction, along with the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSHPx). The data were related to the corresponding metabolic rates. MtDNA content was highest in heart and lowest in spleen. delta mtDNA4834 was detected in all ten tissues and organs, and its amount was highest in liver and lowest in intestine. In heart, lung, muscle, and bone-marrow the deletion could not be quantified because of a point mutation, an A-->T transition at position 8107. Activities of SOD and GSHPx were highest in liver and lowest in intestinal mucosa. A negative correlation between mtDNA content and delta mtDNA4834, and a positive correlation between metabolic rate, GSHPx, and the deletion was found. These results suggest that the occurrence of delta mtDNA4834 in rat is related to oxidative stress. [less ▲]

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See detailQuantification par déformation
Poncin, Norbert UL

Article for general public (2002)

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See detailQuantifications par déformations formelles et non formelles de la boule unité de C^n
Korvers, Stéphane UL

Doctoral thesis (2014)

À la frontière de domaines de recherche tels que la géométrie différentielle, l’analyse harmonique sur les espaces homogènes, les équations aux dérivées partielles ou la théorie des fonctions spéciales en ... [more ▼]

À la frontière de domaines de recherche tels que la géométrie différentielle, l’analyse harmonique sur les espaces homogènes, les équations aux dérivées partielles ou la théorie des fonctions spéciales en physique mathématique, cet ouvrage propose au lecteur de découvrir la quantification par déformation des domaines bornés homogènes complexes sous un nouveau jour. Une étude géométrique des nombreuses facettes de la boule unité de l’espace de n variables complexes comme brique élémentaire de ces domaines précède l’exposé des recherches menées par l’auteur dans le cadre de sa thèse de doctorat. Celles-ci visent notamment la réalisation explicite de l’ensemble des quantifications par déformations sur cette variété. À ces fins, il est montré qu’une telle réalisation se ramène à une hiérarchie d’équations aux dérivées partielles explicite dont certaines solutions définissent des opérateurs de convolution entrelaçant la théorie des déformations au niveau de la boule unité avec celle d’une contraction de courbure de cet espace. La résolution de ces équations est discutée sous plusieurs angles, laissant entrevoir de multiples perspectives à ce travail. [less ▲]

Detailed reference viewed: 54 (5 UL)
See detailQuantifizierung und Visualisierung. Anknüpfungspunkte in den Geschichtswissenschaften
Kerschbaumer, Florian; During, Marten UL

in During, Marten; Eumann, Ulrich; Stark, Martin (Eds.) Handbuch Historische Netzwerkforschung (2016)

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See detailQuantifying and Localizing the Mitochondrial Proteome Across Five Tissues in A Mouse Population.
Williams, Evan UL; Wu, Yibo; Wolski, Witold et al

in Molecular and Cellular Proteomics (2018), 17(9), 1766-1777

We have used SWATH mass spectrometry to quantify 3648 proteins across 76 proteomes collected from genetically diverse BXD mouse strains in two fractions (mitochondria and total cell) from five tissues ... [more ▼]

We have used SWATH mass spectrometry to quantify 3648 proteins across 76 proteomes collected from genetically diverse BXD mouse strains in two fractions (mitochondria and total cell) from five tissues: liver, quadriceps, heart, brain, and brown adipose (BAT). Across tissues, expression covariation between genes' proteins and transcripts-measured in the same individuals-broadly aligned. Covariation was however far stronger in certain subsets than others: only 8% of transcripts in the lowest expression and variance quintile covaried with their protein, in contrast to 65% of transcripts in the highest quintiles. Key functional differences among the 3648 genes were also observed across tissues, with electron transport chain (ETC) genes particularly investigated. ETC complex proteins covary and form strong gene networks according to tissue, but their equivalent transcripts do not. Certain physiological consequences, such as the depletion of ATP synthase in BAT, are thus obscured in transcript data. Lastly, we compared the quantitative proteomic measurements between the total cell and mitochondrial fractions for the five tissues. The resulting enrichment score highlighted several hundred proteins which were strongly enriched in mitochondria, which included several dozen proteins were not reported in literature to be mitochondrially localized. Four of these candidates were selected for biochemical validation, where we found MTAP, SOAT2, and IMPDH2 to be localized inside the mitochondria, whereas ABCC6 was in the mitochondria-associated membrane. These findings demonstrate the synergies of a multi-omics approach to study complex metabolic processes, and this provides a resource for further discovery and analysis of proteoforms, modified proteins, and protein localization. [less ▲]

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See detailQuantifying crosstalk in biochemical systems
Yeung, Enoch; Kim, Jongmin; Yuan, Ye et al

in The proceedings of the 51st IEEE Conference on Decision and Control (2012)

Recent work has introduced biocircuit architectures that exhibit robust oscillatory behavior in organisms ranging from cyanobacteria to mammals. Complementary research in synthetic biology has introduced ... [more ▼]

Recent work has introduced biocircuit architectures that exhibit robust oscillatory behavior in organisms ranging from cyanobacteria to mammals. Complementary research in synthetic biology has introduced oscillators in vivo and in vitro suggesting that robust oscillation can be recapitulated using a small number of biochemical components. In this work, we introduce signaling crosstalk in biocircuits as a consequence of enzyme-mediated biochemical reactions. As a motivating example, we consider an in vitro oscillator with two types of crosstalk: crosstalk in production and degradation of RNA signals. We then propose a framework for quantifying crosstalk and use it to derive several dynamical constraints and suggest design techniques for ameliorating crosstalk in vitro biochemical systems. We demonstrate that the effects of crosstalk can be attenuated through the effective tuning of two key parameters in order to recover desired system dynamics. As an example, we show that by changing the balance between production and degradation crosstalk, we can tune a system to be stable or exhibit oscillatory behavior. [less ▲]

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See detailQuantifying disagreement in argument-based reasoning
Booth, Richard UL; Caminada, Martin UL; Podlaszewski, Mikołaj UL et al

in 11th International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2012) (2012)

An argumentation framework can be seen as expressing, in an abstract way, the conflicting information of an underlying logical knowledge base. This conflicting information often allows for the presence of ... [more ▼]

An argumentation framework can be seen as expressing, in an abstract way, the conflicting information of an underlying logical knowledge base. This conflicting information often allows for the presence of more than one possible reasonable position (extension/labelling) which one can take. A relevant question, therefore, is how much these positions differ from each other. In the current paper, we will examine the issue of how to define meaningful measures of distance between the (complete) labellings of a given argumentation framework. We provide concrete distance measures based on argument-wise label difference, as well as based on the notion of critical sets, and examine their properties. [less ▲]

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See detailQuantifying disagreement in argument-based reasoning
Booth, Richard UL; Caminada, Martin UL; Podlaszewski, Mikołaj UL et al

Scientific Conference (2011)

Detailed reference viewed: 150 (3 UL)
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See detailQuantifying information flow in interactive systems
Mestel, David UL

in 2019 IEEE 32nd Computer Security Foundations Symposium (CSF) (2019)

We consider the problem of quantifying information flow in interactive systems, modelled as finite-state transducers in the style of Goguen and Meseguer. Our main result is that if the system is ... [more ▼]

We consider the problem of quantifying information flow in interactive systems, modelled as finite-state transducers in the style of Goguen and Meseguer. Our main result is that if the system is deterministic then the information flow is either logarithmic or linear, and there is a polynomial-time algorithm to distinguish the two cases and compute the rate of logarithmic flow. To achieve this we first extend the theory of information leakage through channels to the case of interactive systems, and establish a number of results which greatly simplify computation. We then show that for deterministic systems the information flow corresponds to the growth rate of antichains inside a certain regular language, a property called the width of the language. In a companion work we have shown that there is a dichotomy between polynomial and exponential antichain growth, and a polynomial time algorithm to distinguish the two cases and to compute the order of polynomial growth. We observe that these two cases correspond to logarithmic and linear information flow respectively. Finally, we formulate several attractive open problems, covering the cases of probabilistic systems, systems with more than two users and nondeterministic systems where the nondeterminism is assumed to be innocent rather than demonic. [less ▲]

Detailed reference viewed: 94 (6 UL)
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See detailQuantifying location sociality
Pang, Jun UL; Zhang, Yang

in Proc. 28th ACM Conference on Hypertext and Social Media - HT'17 (2017)

Detailed reference viewed: 95 (1 UL)
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See detailQuantifying partial observability in network sensor location problems
Viti, Francesco UL; Rinaldi, Marco; Corman, Francesco

Scientific Conference (2013)

Detailed reference viewed: 79 (4 UL)
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See detailQuantifying Preferences and Responsiveness of Marine Zooplankton to Changing Environmental Conditions using Microfluidics
Ramanathan, Nirupama UL; Simakov, Oleg; Merten, Christoph et al

in PLoS ONE (2015)

Detailed reference viewed: 109 (2 UL)
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See detailQuantifying the Local Economic Growth Impact of Hurricane Strikes: An Analysis from Outer Space for the Caribbean
Bertinelli, Luisito UL; Strobl, Eric

in Journal of Applied Meteorology & Climatology (2013), 52(8), 1688-1697

Studies of the impact of hurricanes on economic activity typically are restricted to a very aggregate level of analysis because of the lack of spatially disaggregated data. In this paper nightlight ... [more ▼]

Studies of the impact of hurricanes on economic activity typically are restricted to a very aggregate level of analysis because of the lack of spatially disaggregated data. In this paper nightlight satellite imagery is employed as a measure of local economic activity in conjunction with a local proxy for potential hurricane destruction generated from a wind field model to statistically assess the impact of hurricane strikes on local economic growth. The regression results suggest that on average hurricane strikes reduce income growth by around 1.5% at the local level, with no effect beyond the year of the strike. This estimated impact from localized data is more than 2 times that implied by aggregate analyses. [less ▲]

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See detailQuantifying the role of mechanics in the free and encapsulated growth of cancer spheroids
Urcun, Stéphane UL

E-print/Working paper (2020)

Mechanics is of primordial importance to understand cancer; hence, experimental and mathematical models providing quantitative information and play a pivotal role on the development of new therapies ... [more ▼]

Mechanics is of primordial importance to understand cancer; hence, experimental and mathematical models providing quantitative information and play a pivotal role on the development of new therapies. Within this context, encapsulated spheroids are emerging as exceptional in vitro tools to investigate the impact of mechanical forces on tumor growth, since from the deformation of the alginate capsule the internal pressure can be retrieved. We show that bio-chemo-poro-mechanics is a suitable theoretical framework to understand, explain and design these in vitro experiments. Such mechanistic models are based on a set of coupled partial differential equations solved within an open-source framework (FEniCS). Through sensitivity analyses, our mathematical model suggests that the main parameters determining the encapsulated and free growth configurations are independent, this observation indicates that radically different phenomena are at play. This demonstrates potentialities of reactive porous media mechanics in oncophysics and can serve to supplement in vivo clinical data. [less ▲]

Detailed reference viewed: 79 (5 UL)
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 ▲]

Detailed reference viewed: 112 (9 UL)