11 research outputs found

    Application Of Numerical Modelling For Conceptualizing Abstraction Rate Control In A Well Field Under Complex Boundary Conditions

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    This paper aims at presenting a concept for regulating water abstraction from a well field which ensures an efficient exploration of river filtrate while complying with defined minimum residence time of inflowing water. Being located on an island between a river and an attendant channel, the investigated well field consists of eight radial collector wells aligned parallel to the river flow direction. The water-level in the river is kept comparatively constant due to a downstream hydropower plant. In the channel, the water level is controlled by two weirs. Following a defined hydrograph with an amplitude of about one meter, the channel water level is on average four meters below the water level of the river. Therefore, the boundary conditions for the well field are subject to strong seasonal fluctuations. For legal reasons, water originating from the channel must remain in the underground for at least 60 days. To analyse on-site flow conditions, a three dimensional finite difference model was developed, calibrated and validated. The water balances of 23 observed steady state conditions with different abstractions from the wells and varying basic conditions were computed with the model. The computed inflow rates from the channel were analysed by comparing them with observed hydraulic heads and it was possible to show a high correlation with the ratio of certain hydraulic head gradients. A linear correlation (R² \u3e0.9) of the quantity and the flow time of inflowing water from the channel could be formulated by analysing the modelling results. By combining these findings, it was possible to develop a criterion for restricting the abstraction from each well according to a minimum water-flow time without the requirement of a parallel operated numerical model. The underlying parameters are computed from hydraulic head values enabling automatically real time control of a non-measurable value through measurable parameters

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Combinations of single-top-quark production cross-section measurements and vertical bar f(LV)V(tb)vertical bar determinations at root s=7 and 8 TeV with the ATLAS and CMS experiments

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    This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb(-1) at = 7 TeV and 12.2 to 20.3 fb(-1) at = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 +/- 5.7 pb and 87.7 +/- 5.8 pb at = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 +/- 4.1 pb and 23.1 +/- 3.6 pb at = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 +/- 1.4 pb at = 8 TeV. The square of the magnitude of the CKM matrix element V-tb multiplied by a form factor f(LV) is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |V-td|, |V-ts| << |V-tb|. All the |f(LV)V(tb)|(2) determinations, extracted from individual ratios at = 7 and 8 TeV, are combined, resulting in |f(LV)V(tb)| = 1.02 +/- 0.04 (meas.) +/- 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions.Peer reviewe

    Educational Resources for Geoethical Aspects of Water Management

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    Global water resources are a critical value for the future of humankind. Conflicts and wars seem to rise because of such critical resources. While water-scarce countries are under extreme pressure on the long-term scale, also water-rich countries in Europe, such as Austria, face local conflicts of interest between water supply, tourism, agriculture, hydropower and ecology, for instance. Higher Education must address these conflicts and the new concepts of geoethics offer the conceptional thinking to do so. Based on educational resources for Higher Education that have been developed in the field of “Geoethics and Water Management” under the Erasmus+ co-funded project GOAL (Geoethics Outcomes and Awareness Learning), selected water-related conflicts are discussed. The cases selected for developing the educational resources are water use conflicts and geoethical aspects of hydropower plants. The educational resources include a subsequent procedure for applying them with students. Outcomes from the educational resources show that issues related to water management often create geoethical conflicts and dilemmas, and an interconnection between several Sustainable Development Goals can be established. Applying the educational resources shall enable geoscientists to contribute towards sustainable development of Earth’s future by a more holistic view

    Measurements of ttˉt\bar{t} differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in pppp collisions at s=13\sqrt{s}=13\, TeV using the ATLAS detector

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    Measurements are made of differential cross-sections of highly boosted pair-produced top quarks as a function of top-quark and ttˉt\bar{t} system kinematic observables using proton--proton collisions at a center-of-mass energy of s=13\sqrt{s} = 13 TeV. The data set corresponds to an integrated luminosity of 36.136.1 fb1^{-1}, recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. Events with two large-radius jets in the final state, one with transverse momentum pT>500p_{\rm T} > 500 GeV and a second with pT>350p_{\rm T}>350 GeV, are used for the measurement. The top-quark candidates are separated from the multijet background using jet substructure information and association with a bb-tagged jet. The measured spectra are corrected for detector effects to a particle-level fiducial phase space and a parton-level limited phase space, and are compared to several Monte Carlo simulations by means of calculated χ2\chi^2 values. The cross-section for ttˉt\bar{t} production in the fiducial phase-space region is 292±7 (stat)±76(syst)292 \pm 7 \ \rm{(stat)} \pm 76 \rm{(syst)} fb, to be compared to the theoretical prediction of 384±36384 \pm 36 fb

    Measurements of ttˉt\bar{t} differential cross-sections of highly boosted top quarks decaying to all-hadronic final states in pppp collisions at s=13\sqrt{s}=13\, TeV using the ATLAS detector

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    Measurements are made of differential cross-sections of highly boosted pair-produced top quarks as a function of top-quark and ttˉt\bar{t} system kinematic observables using proton--proton collisions at a center-of-mass energy of s=13\sqrt{s} = 13 TeV. The data set corresponds to an integrated luminosity of 36.136.1 fb1^{-1}, recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. Events with two large-radius jets in the final state, one with transverse momentum pT>500p_{\rm T} > 500 GeV and a second with pT>350p_{\rm T}>350 GeV, are used for the measurement. The top-quark candidates are separated from the multijet background using jet substructure information and association with a bb-tagged jet. The measured spectra are corrected for detector effects to a particle-level fiducial phase space and a parton-level limited phase space, and are compared to several Monte Carlo simulations by means of calculated χ2\chi^2 values. The cross-section for ttˉt\bar{t} production in the fiducial phase-space region is 292±7 (stat)±76(syst)292 \pm 7 \ \rm{(stat)} \pm 76 \rm{(syst)} fb, to be compared to the theoretical prediction of 384±36384 \pm 36 fb
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