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See detailThe promise of solution-processed Fe2GeS4 thin films in iron chalcogenide photovoltaics
Liu, Mimi; Berg, Dominik M.; Hwang, Po-Yu et al

in Journal of Materials Science (2018)

The olivine Fe2GeS4, featuring non-toxic elements, cost-effective synthesis, and suitable optoelectronic properties, recently emerged as a promising light-absorbing candidate. Fe2GeS4 precursor powders ... [more ▼]

The olivine Fe2GeS4, featuring non-toxic elements, cost-effective synthesis, and suitable optoelectronic properties, recently emerged as a promising light-absorbing candidate. Fe2GeS4 precursor powders obtained via a simple solutionbased process were converted to highly crystalline Fe2GeS4 powders upon a thermal treatment in controlled atmosphere. Thin films fabricated by dip coating in the Fe2GeS4 precursor dispersion and subjected to the same thermal treatment render high-purity Fe2GeS4 thin films with a band gap of 1.4 eV, measured by room-temperature photoluminescence. Using Fe2GeS4 thin films as the sole absorber in a solution-based solar cell, open-circuit voltages of 361 mV are observed, while the use of the Fe2GeS4 films as counter electrodes in dyesensitized solar cell constructs enhances the overall power conversion efficiency of the cell by a factor of five. This is the first report of a photovoltaic device based on Fe2GeS4. [less ▲]

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See detailThe value of education among immigrants and non-immigrants and how this translates into educational aspirations: a comparison of four European countries
Hadjar, Andreas UL; Scharf, Jan UL

in Journal of Ethnic and Migration Studies (2018), early online

Starting out from the frequent empirical finding that immigrants exhibit higher educational aspirations than non-immigrants, we analyse the role of immigrants’ value of education, i.e. the subjective ... [more ▼]

Starting out from the frequent empirical finding that immigrants exhibit higher educational aspirations than non-immigrants, we analyse the role of immigrants’ value of education, i.e. the subjective belief that education is beneficial for one’s life, in idealistic and realistic educational aspirations in four distinct institutional settings, comparing Sweden, Germany, the Netherlands and England. While the first part of the analyses relates to how immigrants differ from non-immigrants in the value they assign to education, the second part centres on country differences considering immigrant integration policies and education systems as crucial factors. A third part relates to the links between the value of education and educational aspirations to gain some insight into how the value of education may contribute to educational decisions. Analyses are based on longitudinal data of the Children of Immigrants Longitudinal Survey in Four European Countries (CILS4EU). While results show that immigrants assign a higher value to education, the value of education does play a minor role in idealistic and realistic educational aspirations. The results of the country comparison are rather ambivalent, including very weak support for the argument that immigrants strive for education to a higher extent in countries with less favourable conditions. [less ▲]

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See detailMicrofluidic Tensiometry Technique for the Characterization of the Interfacial Tension between Immiscible Liquids.
Honaker, Lawrence William UL; Lagerwall, Jan UL; Jampani, Venkata UL

in Langmuir (2018)

The interfacial tension between two immiscible fluids is of critical importance for understanding many natural phenomena as well as in industrial production processes; however, it can be challenging to ... [more ▼]

The interfacial tension between two immiscible fluids is of critical importance for understanding many natural phenomena as well as in industrial production processes; however, it can be challenging to measure this parameter with high accuracy. Most commonly used techniques have significant shortcomings because of their reliance on other data such as density or viscosity. To overcome these issues, we devise a technique that works with very small sample quantities and does not require any data about either fluid, based on micropipette aspiration techniques. The method facilitates the generation of a droplet of one fluid inside of the other, followed by immediate in situ aspiration of the droplet into a constricted channel. A modified Young-Laplace equation is then used to relate the pressure needed to produce a given deformation of the droplet's radius to the interfacial tension. We demonstrate this technique on different systems with interfacial tensions ranging from sub-millinewton per meter to several hundred millinewton per meter, thus over 4 orders of magnitude, obtaining precise results in agreement with the literature solely from experimental observations of the droplet deformation. [less ▲]

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See detailConservation Laws Shape Dissipation
Rao, Riccardo UL; Esposito, Massimiliano UL

in New Journal of Physics (2018), 20

Starting from the most general formulation of stochastic thermodynamics—i.e. a thermodynamically consistent nonautonomous stochastic dynamics describing systems in contact with several reservoirs —we ... [more ▼]

Starting from the most general formulation of stochastic thermodynamics—i.e. a thermodynamically consistent nonautonomous stochastic dynamics describing systems in contact with several reservoirs —we define a procedure to identify the conservative and the minimal set of nonconservative contributions in the entropy production. The former is expressed as the difference between changes caused by time-dependent drivings and a generalized potential difference. The latter is a sum over the minimal set of flux-force contributions controlling the dissipative flows across the system. When the system is initially prepared at equilibrium (e.g. by turning off drivings and forces), a finite-time detailed fluctuation theorem holds for the different contributions. Our approach relies on identifying the complete set of conserved quantities and can be viewed as the extension of the theory of generalized Gibbs ensembles to nonequilibrium situations. [less ▲]

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See detailSimulation-Based Fault Injection as a Verification Oracle for the Engineering of Time-Triggered Ethernet networks
Fejoz, Loïc; Regnier, Bruno; Miramont, Philippe et al

Scientific Conference (2018, February 02)

TTEthernet (TTE) is considered for use as high-speed backbone in the avionics of next-generation orbital space launchers. Given the key role of communication in launchers, the OEM must acquire a precise ... [more ▼]

TTEthernet (TTE) is considered for use as high-speed backbone in the avionics of next-generation orbital space launchers. Given the key role of communication in launchers, the OEM must acquire a precise understanding of TTE’s functioning and its performances in nominal and error conditions. This holds especially true for the clock synchronization algorithm, the cornerstone of time-triggered communication in TTE, which involves complex distributed algorithms. In this study, we use both an experimental platform and fault-injection on a simulation model to gain quantified insights in these questions. We first describe a fine-grained simulation model of TTE model and discuss how it has been validated against communication traces recorded on the TTE platform. We then present experiments that evaluate the accuracy of the clock synchronization in TTE in the fault-free case as well as considering permanent link failure and transient transmission errors. Finally, we discuss what we have learned during the project in terms of development process and programming language support for complex simulation models used in the design of critical systems. [less ▲]

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See detailInsights on the Performance and Configuration of AVB and TSN in Automotive Ethernet Networks
Migge, Jörn; Villanueva, Josetxo; Navet, Nicolas UL et al

Scientific Conference (2018, February 02)

Switched Ethernet is profoundly reshaping in-car communications. To meet the diverse real-time requirements in automotive communications, Quality-of-Service protocols that go beyond the mere use of ... [more ▼]

Switched Ethernet is profoundly reshaping in-car communications. To meet the diverse real-time requirements in automotive communications, Quality-of-Service protocols that go beyond the mere use of priorities are required. In this work, the basic questions that we investigate on a case-study with diverse and demanding communication requirements is what can we expect from the various protocols aimed at providing a better timing Quality of Service on top of Ethernet? And how to use them? Especially how to use them in a combined manner. We will focus on the Credit-Based Shaper of AVB, the Time-Aware Shaper of TSN and the use of priorities as defined in IEEE802.1Q. The performance metrics considered are the distributions of the communication latencies, obtained by simulation, as well as upper bounds on these quantities obtained by worst-case schedulability analysis. If there have been over the last 5 years numerous studies on the performance of AVB CBS, the literature on comparing AVB to TSN and other candidate protocols is still sparse. To the best of our knowledge, this empirical study is the first to consider most protocols currently considered in the automotive domain, with the aim to gain insights into the different technological, design and configurations alternatives. In particular, an objective of this study is to identify key problems that need to be solved in order to further automate network design and configuration. [less ▲]

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See detailIdentification and Characterization of Variant Intolerant Sites across Human Protein 3-Dimensional Structures
Iqbal, Sumaiya; Berg Jespersen, Jakob; Perez-Palma, Eduardo et al

in Biophysical Journal (2018, February 02), 114(3, Suppl. 1), 664

The functional interpretation of genetic variation in disease-associated genes is far outpaced by data generation. Existing algorithms for prediction of variant consequences do not adequately distinguish ... [more ▼]

The functional interpretation of genetic variation in disease-associated genes is far outpaced by data generation. Existing algorithms for prediction of variant consequences do not adequately distinguish pathogenic variants from benign rare variants. This lack of statistical and bioinformatics analyses, accompanied by an ever-increasing number of identified variants in biomedical research and clinical applications, has become a major challenge. Established methods to predict the functional effect of genetic variation use the degree of amino acid conservation across species in linear protein sequence alignment. More recent methods include the spatial distribution pattern of known patient and control variants. Here, we propose to combine the linear conservation and spatial constrained based scores to devise a novel score that incorporates 3-dimensional structural properties of amino acid residues, such as the solvent-accessible surface area, degree of flexibility, secondary structure propensity and binding tendency, to quantify the effect of amino acid substitutions. For this study, we develop a framework for large-scale mapping of established linear sequence-based paralog and ortholog conservation scores onto the tertiary structures of human proteins. This framework can be utilized to map the spatial distribution of mutations on solved protein structures as well as homology models. As a proof of concept, using a homology model of the human Nav1.2 voltage-gated sodium channel structure, we observe spatial clustering in distinct domains of mutations, associated with Autism Spectrum Disorder (>20 variants) and Epilepsy (>100 variants), that exert opposing effects on channel function. We are currently characterizing all variants (>300k individuals) found in ClinVar, the largest disease variant database, as well as variants identified in >140k individuals from general population. The variant mapping framework and our score, informed with structural information, will be useful in identifying structural motifs of proteins associated with disease risk. [less ▲]

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See detailWho Decides What? Judicial Deference in International Economic Adjudication
Fahner, Johannes Hendrik UL

Presentation (2018, February 01)

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See detailReligionsunterricht in Luxemburg aus diskurstheoretischer Sicht: eine spannende Geschichte und eine spannungsvolle Zukunft
Weber, Jean-Marie UL

in Jean, Ehret; Zeien, Jean-Louis (Eds.) Herausforderung Religion(en) und Schule(n) (2018)

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See detailOn the effect of grains interface parameters on the macroscopic properties of polycrystalline materials
Akbari, Ahmad; Kerfriden, Pierre; Bordas, Stéphane UL

in Computers & Structures (2018), 196

In this paper, the influence of microscopic parameters on the macroscopic behaviour of polycrystalline materials under different loading configuration is investigated. Linear elastic grains with zero ... [more ▼]

In this paper, the influence of microscopic parameters on the macroscopic behaviour of polycrystalline materials under different loading configuration is investigated. Linear elastic grains with zero thickness cohesive interfaces are considered at the microscale with in depth introduction of effective parameters. A multiscale method based on homogenisation technique is employed to bridge the scales. In order to minimize the homogenisation error, a representative volume element (RVE) of the microscopic structure is statistically determined to be used in the numerical analysis. For each loading condition of the RVE, several numerical examinations are conducted to illustrate the relationship between the microscopic parameters. Finally, the effects of microscopic critical fracture energies, maximum tensile and shear strengths of grain interfaces on the mechanical properties, i.e. stress-strain curve and yield surface at the macroscale are discussed in details. It is shown that macroscopic yield surface and stress strain curves can be used to characterise the microscopic properties. [less ▲]

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See detailLimit theorems for symmetric U-statistics using contractions
Döbler, Christian UL; Peccati, Giovanni UL

E-print/Working paper (2018)

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See detailUniversity of California, Berkeley, Institute of European Studies (IES) Fall 2017 Newsletter
Institute of European Studies, UC Berkeley; Paravantis, Spero UL

Report (2018)

The Fall 2017 newsletter of the University of California, Berkeley, Institute of European Studies (IES). I was a Visiting Scholar at IES from August 2017 to Feb 2018, and from March 1st 2018, I will ... [more ▼]

The Fall 2017 newsletter of the University of California, Berkeley, Institute of European Studies (IES). I was a Visiting Scholar at IES from August 2017 to Feb 2018, and from March 1st 2018, I will become an IES Senior Fellow. My bio is on page 8, and summaries of my lectures are on page 30 (Migration) and 31 (WWI and WWII Reparations and European Integration). [less ▲]

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See detailDie Ideenfabrik. Universitäten als Produzenten von Wissen
Zimmermann, Julia Maria; Powell, Justin J W UL; Dusdal, Jennifer UL

Article for general public (2018)

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See detailContributions to the asymptotic study of Hermite driven processes
Tran, Thi Thanh Diu UL

Doctoral thesis (2018)

This thesis consists of two parts. Part I is an introduction to Hermite processes, Hermite random fields, Fisher information and to the papers constituting the thesis. More precisely, in Section 1 we ... [more ▼]

This thesis consists of two parts. Part I is an introduction to Hermite processes, Hermite random fields, Fisher information and to the papers constituting the thesis. More precisely, in Section 1 we introduce Hermite processes in a nutshell, as well as some of its basic properties. It is the necessary background for the articles [a] and [c]. In Section 2 we consider briefly the multiparameter Hermite random fields and we study some less elementary facts which are used in the article [b]. In section 3, we recall some terminology about Fisher information related to the article [d]. Finally, our articles [a] to [d] are summarised in Section 4. Part II consists of the articles themselves: [a] T.T. Diu Tran (2017): Non-central limit theorem for quadratic functionals of Hermite-driven long memory moving average processes. Stochastic and Dynamics, 18, no. 4. [b] T.T. Diu Tran (2016): Asymptotic behavior for quadratic variations of nonGaussian multiparameter Hermite random fields. Under revision for Probability and Mathematical Statistics. [c] I. Nourdin, T.T. Diu Tran (2017): Statistical inference for Vasicek-type model driven by Hermite processes. Submitted to Stochastic Process and their Applications. [d] T.T. Diu Tran (2017+): Fisher information and multivariate Fouth Moment Theorem. Main results have already been obtained. It should be submitted soon. [less ▲]

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See detailReply: No evidence for rare TRAP1 mutations influencing the risk of idiopathic Parkinson’s disease
Fitzgerald, Julia C.; Zimprich, Alexander; Bobbili, Dheeraj Reddy UL et al

in Brain : A Journal of Neurology (2018)

Sir, In their letter in this issue, Gaare and colleagues (2018) state that TRAP1 may not be a Parkinson’s disease gene because of lack of genetic association. In response, we welcome their data analyses ... [more ▼]

Sir, In their letter in this issue, Gaare and colleagues (2018) state that TRAP1 may not be a Parkinson’s disease gene because of lack of genetic association. In response, we welcome their data analyses and we welcome any further genetic analyses of TRAP1 variants in additional Parkinson’s disease genetic datasets, including the reanalysis of open access datasets such as the Parkinson’s Progressive Markers Initiative (PPMI). Our point of view is that TRAP1 is an interesting effector protein that our study unequivocally showed is relevant to Parkinson’s disease signaling in the context of mitochondrial regulation. Furthermore, the overall contribution of TRAP1 genetic variants to Parkinson’s disease was not the focus of our recent paper in Brain (Fitzgerald et al., 2017). [less ▲]

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See detailThe Effects of Skills Underutilization and Unemployment on Hiring Decisions
Samuel, Robin UL; Sacchi, Stefan

Presentation (2018, January 23)

Research suggests negative effects of unemployment and skill underutilization on subsequent labor market outcomes. Among others, signaling theory has been used to explain why recruiters may evaluate ... [more ▼]

Research suggests negative effects of unemployment and skill underutilization on subsequent labor market outcomes. Among others, signaling theory has been used to explain why recruiters may evaluate competence and commitment of some job applicants less favorably than others. However, various country-, firm-, occupation-, and job-specific context factors may moderate such scarring effects. For example, a high youth unemployment rate may be associated with more scarring of previous unemployment spells and these effects might be different for occupations with different skill requirements. In this contribution, we explore the moderating role of transaction costs, i.e., the direct and indirect costs of recruiting and training new employees for scarring due to previous unemployment and skill underutilization. Furthermore, we investigate the extent to which the perceived difficulty of recruiting moderates these effects. Using data from a recent large-scale factorial survey of recruiters in four European countries (N~=~2,000) and employing multilevel linear regression models, we found, overall, scarring due to skill underutilization to exceed scarring due to unemployment. Skill underutilization was especially penalized when recruiting for a particular position was considered easy. Indirect transaction costs, particularly anticipated time required for organizational socialization, were negatively associated with unemployment scarring, but positively with scarring due to skill underutilization. Unemployment spells only had a negative effect on hiring chances, for jobs where there were monetary expenses for introductory trainings. Our findings constitute new evidence on the heterogeneity of scarring effects on hiring chances. We further contribute to the literature by highlighting the role of transaction costs and labor market performance. [less ▲]

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See detailExome-wide analysis of mutational burden in patients with typical and atypical Rolandic Epilepsy
Bobbili, Dheeraj Reddy UL; Lal, Dennis; May, Patrick UL et al

in European Journal of Human Genetics (2018)

Rolandic Epilepsy (RE) is the most common focal epilepsy in childhood. To date no hypothesis-free exome-wide mutational screen has been conducted for RE and Atypical RE (ARE). Here we report on whole ... [more ▼]

Rolandic Epilepsy (RE) is the most common focal epilepsy in childhood. To date no hypothesis-free exome-wide mutational screen has been conducted for RE and Atypical RE (ARE). Here we report on whole-exome sequencing of 194 unrelated patients with RE/ARE and 567 ethnically matched population controls. We identified an exome-wide significantly enriched burden for deleterious and loss-of-function variants only for the established RE/ARE gene GRIN2A. The statistical significance of the enrichment disappeared after removing ARE patients. For several disease-related gene-sets, an odds ratio > 1 was detected for loss-of-function variants. [less ▲]

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See detailContemporary Russia: Gefangen im Kreml - Die russischen First Ladies
Baumeister, Annette; Ganschow, Inna UL

in Hartung, Florian (Ed.) Februar Film (2018)

Als 1917 die Revolution Frauen den Männern gleichstellt, ist die Sowjetunion das fortschrittlichste Land der Welt: Frauen dürfen wählen, studieren und in die Politik gehen. Allen voran Nadeschda Krupskaja ... [more ▼]

Als 1917 die Revolution Frauen den Männern gleichstellt, ist die Sowjetunion das fortschrittlichste Land der Welt: Frauen dürfen wählen, studieren und in die Politik gehen. Allen voran Nadeschda Krupskaja, die Ehefrau und Kampfgefährtin von Revolutionsführer Lenin. Mit seinem Nachfolger Stalin jedoch verschwinden die Frauen im Kreml wieder von der Bildfläche. Der Diktator entmachtet Krupskaja, seine Ehefrau Nadeschda Allilujewa darf nicht mehr öffentlich auftreten. Sie vereinsamt und nimmt sich 1932 das Leben. Den anderen Kremlfrauen verordnet Stalin ein traditionelles Lebensmodell, das bis heute gilt. Während damals gewöhnliche Russinnen zur Arbeit gehen mussten, bleiben sie meist unfreiwillig zuhause. So ergeht es auch Nina Petrowna, der Lebensgefährtin von Nikita Chruschtschow, und der Ehefrau von Leonid Breschnew, Viktoria Breschnewa. Beide geben zugunsten der Karriere ihrer Männer den Beruf auf und ebnen damit ihren Männern den Weg an die Spitze des Staates. Dies ändert sich erst gegen Ende der Sowjetunion. Trotz politischer Umwälzungen wird auch von Raissa Gorbatschowa, der Ehefrau von Michail Gorbatschow erwartet, dass sie sich zurückhält und gehorcht. Doch sie lehnt sich auf und handelt eigenständig. Am Ende zerbricht die Frau des großen Reformers, Raissa Gorbatschowa, am starren Kremlapparat. Nur einer gelingt es, sich aus dem Bann der Macht zu befreien: Ljudmila Putina. [less ▲]

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