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See detailA Comparative Study of Thermoelectric Properties of Monolayer, Bilayer and Bulk CrI3
Suprayoga, E; Hanna, M. Y.; Hasdeo, Eddwi Hesky UL et al

in AIP Conference Proceedings (2021), 2382(1), 020004

We comparatively study the electronic and thermoelectric properties of the monolayer, bilayer, and bulk CrI3 by density functional theory (DFT). We show that, according to the DFT calculation, those ... [more ▼]

We comparatively study the electronic and thermoelectric properties of the monolayer, bilayer, and bulk CrI3 by density functional theory (DFT). We show that, according to the DFT calculation, those materials are magnetic semiconductors with ferromagnetic (FM) in monolayer, antiferromagnetic (AFM) in the bilayer, back to FM in the bulk structure. The thermoelectric properties of those materials are evaluated by using the Boltzmann transport equation (BTE) with a constant relaxation time approximation (RTA). At room temperature, we obtain bulk CrI3 has more significant electrical conductivity than monolayer and bilayer CrI3, while the Seebeck coefficient is similar that implied the bulk CrI3 has a better thermoelectric performance. In those systems, the optimum power factor is obtained by shifting the chemical potential of CrI3 by 1 eV with p-type doping. [less ▲]

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See detailQuantitative trait locus mapping identifies a locus linked to striatal dopamine and points to collagen IV alpha-6 chain as a novel regulator of striatal axonal branching in mice
Thomas, Melanie UL; Gui, Yujuan; Garcia, Pierre UL et al

in Genes, Brain, and Behavior (2021)

Dopaminergic neurons (DA neurons) are controlled by multiple factors, many involved in neurological disease. Parkinson's disease motor symptoms are caused by the demise of nigral DA neurons, leading to ... [more ▼]

Dopaminergic neurons (DA neurons) are controlled by multiple factors, many involved in neurological disease. Parkinson's disease motor symptoms are caused by the demise of nigral DA neurons, leading to loss of striatal dopamine (DA). Here, we measured DA concentration in the dorsal striatum of 32 members of Collaborative Cross (CC) family and their eight founder strains. Striatal DA varied greatly in founders, and differences were highly heritable in the inbred CC progeny. We identified a locus, containing 164 genes, linked to DA concentration in the dorsal striatum on chromosome X. We used RNAseq profiling of the ventral midbrain of two founders with substantial difference in striatal DA–C56BL/6 J and A/J—to highlight potential protein-coding candidates modulating this trait. Among the five differentially expressed genes within the locus, we found that the gene coding for the collagen IV alpha 6 chain (Col4a6) was expressed nine times less in A/J than in C57BL/6J. Using single cell RNA-seq data from developing human midbrain, we found that COL4A6 is highly expressed in radial glia-like cells and neuronal progenitors, indicating a role in neuronal development. Collagen IV alpha-6 chain (COL4A6) controls axogenesis in simple model organisms. Consistent with these findings, A/J mice had less striatal axonal branching than C57BL/6J mice. We tentatively conclude that DA concentration and axonal branching in dorsal striatum are modulated by COL4A6, possibly during development. Our study shows that genetic mapping based on an easily measured Central Nervous System (CNS) trait, using the CC population, combined with follow-up observations, can parse heritability of such a trait, and nominate novel functions for commonly expressed proteins. [less ▲]

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See detailMassive MIMO under Double Scattering Channels: Power Minimization and Congestion Controls
Van Chien, Trinh; Ngo, Hien Quoc; Chatzinotas, Symeon UL et al

in IEEE Transactions on Wireless Communications (2021)

This paper considers a massive MIMO system under the double scattering channels. We derive a closed-form expression of the uplink ergodic spectral efficiency (SE) by exploiting the maximum-ratio combining ... [more ▼]

This paper considers a massive MIMO system under the double scattering channels. We derive a closed-form expression of the uplink ergodic spectral efficiency (SE) by exploiting the maximum-ratio combining technique with imperfect channel state information. We then formulate and solve a total uplink data power optimization problem that aims at simultaneously satisfying the required SEs from all the users with limited power resources. We further propose algorithms to cope with the congestion issue appearing when at least one user is served by lower SE than requested. Numerical results illustrate the effectiveness of our proposed power optimization. More importantly, our proposed congestion-handling algorithms can guarantee the required SEs to many users under congestion, even when the SE requirement is high. [less ▲]

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See detailA conceptual model for understanding vulnerability in the context of migration
Gilodi, Amalia UL

Scientific Conference (2021, August 05)

The notion of ‘vulnerability’ is as popular as it is fuzzy. Its increased prominence in social research and in political and humanitarian discourses on migration has led many scholars and practitioners to ... [more ▼]

The notion of ‘vulnerability’ is as popular as it is fuzzy. Its increased prominence in social research and in political and humanitarian discourses on migration has led many scholars and practitioners to treat the concept as self-explanatory, without problematizing neither its conceptualization nor its use and possible negative societal and psychological consequences. Set within the framework of the EU-funded project MIMY (n°870700), investigating the processes of integration of young migrants in 9 European countries, this paper critically evaluates different conceptualizations and uses of vulnerability and proposes a new multilevel conceptual model for understanding vulnerability in the context of migration. Focusing on different levels of analysis, the model situates individuals and groups in the broader socio-political hierarchies and power dynamics that inevitably affect them (structural vulnerability), acknowledges how these systems are (re)produced in situated interpersonal relationships (situational vulnerability) and accounts for migrants’ biographical and psychological experiences of vulnerability. Focusing on the interrelationships between levels of analysis, the model highlights how macro conditions and definitions of vulnerability may affect individual experiences, through processes such as stigmatization, internalization of stereotypes, disempowerment, but also how individuals can actively negotiate their ascribed ‘vulnerability’ through processes such as resistance, mobilization and collective action. [less ▲]

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See detailLiterature survey of droplet entrainment from water pools
Ouallal, Mohammed UL; Leyer, Stephan UL; Gupta, Sanjeev

in Nuclear Engineering and Design (2021)

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See detailGravity prop and moduli spaces Mg,n
Merkoulov (merkulov), Serguei UL

E-print/Working paper (2021)

Let Mg,n be the moduli space of algebraic curves of genus g with m+n marked points decomposed into the disjoint union of two sets of cardinalities m and n, and H∙c(Mm+n) its compactly supported cohomology ... [more ▼]

Let Mg,n be the moduli space of algebraic curves of genus g with m+n marked points decomposed into the disjoint union of two sets of cardinalities m and n, and H∙c(Mm+n) its compactly supported cohomology group. We prove that the collection of S-bimodules {H∙−mc(Mg,m+n)} has the structure of a properad (called the gravity properad) such that it contains the (degree shifted) E. Getzler's gravity operad as the sub-collection {H∙−1c(M0,1+n)}n≥2. Moreover, we prove that the generators of the 1-dimensional cohomology groups H∙−1c(M0,1+2), H∙−2c(M0,2+1) and H∙−3c(M0,3+0) satisfy with respect to this properadic structure the relations of the (degree shifted) quasi-Lie bialgebra, a fact making the totality of cohomology groups ∏g,m,nH∙c(Mg,m+n)⊗Sopm×Sn(sgnm⊗Idn) into a complex with the differential fully determined by the just mentioned three cohomology classes . It is proven that this complex contains infinitely many cohomology classes, all coming from M. Kontsevich's odd graph complex. The gravity prop structure is established with the help of T. Willwacher's twisting endofunctor (in the category of properads under the operad of Lie algebras) and K. Costello's theory of moduli spaces of nodal disks with marked boundaries and internal marked points (such that each disk contains at most one internal marked point). [less ▲]

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See detailAn Enhanced Spectrum Reservation Framework for Heterogeneous Users in CR-Enabled IoT Networks
Khan, Abd Ullah; Tanveer, Muhammad; Khan, Wali Ullah UL et al

in IEEE Wireless Communications Letters (2021)

Fulfilling the diverse communication requirements of heterogeneous users is envisioned to be one of the key challenges in cognitive radio-enabled IoT networks. To this end, we propose a novel scheme ... [more ▼]

Fulfilling the diverse communication requirements of heterogeneous users is envisioned to be one of the key challenges in cognitive radio-enabled IoT networks. To this end, we propose a novel scheme focused on multi-tier prioritized and heterogeneous regime of users and reservation-based resources allocation. The proposed scheme manipulates the secondary users’ (SUs’) heterogeneity based on their priorities for improving their capacities and blocking probabilities. Besides, the scheme systematically deals with SUs’ dropping for bringing fairness in the service provisioning to SUs. Furthermore, the scheme allows primary users (PUs) to follow an organized approach when accessing channels for mitigating the number of handoffs. Additionally, we propose a dynamic channel reservation algorithm for PUs to enhance spectrum utilization. We leverage the continuous-time Markov chain for system modeling and consider channel failures for making the analysis more realistic. Results confirm the effectiveness of our scheme as compared to the state-of-the-art. [less ▲]

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See detailOptimizing Resource Allocation for 6G NOMA-Enabled Cooperative Vehicular Networks
Ali, Zain; Khan, Wali Ullah UL; Ihsan, Asim et al

in IEEE Open Journal of Intelligent Transportation Systems (2021)

In recent years, the concept of non-orthogonal multiple access (NOMA) has gathered much attention due to its potential to offer high spectral efficiency, present user fairness and grant free access to ... [more ▼]

In recent years, the concept of non-orthogonal multiple access (NOMA) has gathered much attention due to its potential to offer high spectral efficiency, present user fairness and grant free access to sixth generation (6G) vehicular networks. This paper proposes a new optimization framework for NOMA-enabled cooperative vehicular network. In particular, we jointly optimize the vehicle paring, channel assignment, and power allocation at source and relaying vehicles. The objective is to maximize the sum rate of the system subject to the power allocation, minimum rate, relay battery lifetime and successive interference cancelation constraints. To solve the joint optimization problem efficiently, we adopt duality theory followed by Karush-Kuhn-Tucker (KKT) conditions, where the dual variables are iteratively computed through sub-gradient method. Two less complex suboptimal schemes are also presented as the benchmark cooperative vehicular schemes. Simulation results compare the performance of the proposed joint optimization scheme compared to the other benchmark cooperative vehicular schemes. [less ▲]

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See detailLa clause de non-concurrence des associés dans les SCOP : le coopérateur sur le bûcher du droit du travail
Hiez, David UL

in RTD Com: Revue Trimestrielle de Droit Commercial et Economique (2021), (3), 619-626

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See detailSecure Wire Shuffling in the Probing Model
Coron, Jean-Sébastien UL; Spignoli, Lorenzo UL

in Crypto 2021 (2021, August)

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See detailArbitration after BEPS
Haslehner, Werner UL; Kobetsky, Michael

in Kofler, Georg; Mason, Ruth; Rust, Alexander (Eds.) Thinker, Teacher, Traveler – Reimagining International Tax (Essays in Honor of H. David Rosenbloom) (2021)

Following the introduction of increasingly complex international tax rules through the OECD's Base Erosion and Profit Shifting (BEPS) Project, a stronger focus has recently been placed on mandatory ... [more ▼]

Following the introduction of increasingly complex international tax rules through the OECD's Base Erosion and Profit Shifting (BEPS) Project, a stronger focus has recently been placed on mandatory binding dispute resolution mechanisms. Despite its great appeal from the perspectives of effectiveness and economy of procedure, mandatory tax arbitration faces a number of political, practical and also legal difficulties. This chapter, which is dedicated to H. David Rosenbloom, a long-standing champion of tax arbitration, considers those challenges. [less ▲]

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See detailChronic primary pain in the COVID-19 pandemic: how uncertainty and stress impact on functioning and suffering
Meulders, Ann; Vlaeyen, Johan W S; Evers, Andrea W M et al

in Pain (2021)

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See detailGuest Editorial: Space Information Networks: Technological Challenges, Design Issues, and Solutions
Xue, Kaiping; De Cola, Tomaso; Wei, David S.L. et al

in IEEE Network (2021), 35(4), 16-18

It has been expected that the space information networks (SIN), as an extension of the terrestrial network, would provide high-speed, high-capacity, global continuous communication, and data transmission ... [more ▼]

It has been expected that the space information networks (SIN), as an extension of the terrestrial network, would provide high-speed, high-capacity, global continuous communication, and data transmission services anywhere for anyone at any time. With rapid advances in relevant technologies (e.g., satellite miniaturization technology, reusable rocket launch technology, and semiconductor technology), low-orbit satellites, drones, and airships can be integrated into the SIN to supply more comprehensive network connectivity. The standard development organizations including 3GPP, ITU, and ETSI already starts corresponding standardization activities to support nonterrestrial networks in SIN. It can be foreseen that SIN will be expanded to provide not only telephone services but also various kinds of Internet services, and it is thus able to serve many more users with different demands. [less ▲]

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See detailBatching CSIDH Group Actions using AVX-512
Cheng, Hao UL; Fotiadis, Georgios UL; Groszschädl, Johann UL et al

in IACR Transactions on Cryptographic Hardware and Embedded Systems (TCHES) (2021, August), 2021(4), 618-649

Commutative Supersingular Isogeny Diffie-Hellman (or CSIDH for short) is a recently-proposed post-quantum key establishment scheme that belongs to the family of isogeny-based cryptosystems. The CSIDH ... [more ▼]

Commutative Supersingular Isogeny Diffie-Hellman (or CSIDH for short) is a recently-proposed post-quantum key establishment scheme that belongs to the family of isogeny-based cryptosystems. The CSIDH protocol is based on the action of an ideal class group on a set of supersingular elliptic curves and comes with some very attractive features, e.g. the ability to serve as a “drop-in” replacement for the standard elliptic curve Diffie-Hellman protocol. Unfortunately, the execution time of CSIDH is prohibitively high for many real-world applications, mainly due to the enormous computational cost of the underlying group action. Consequently, there is a strong demand for optimizations that increase the efficiency of the class group action evaluation, which is not only important for CSIDH, but also for related cryptosystems like the signature schemes CSI-FiSh and SeaSign. In this paper, we explore how the AVX-512 vector extensions (incl. AVX-512F and AVX-512IFMA) can be utilized to optimize constant-time evaluation of the CSIDH-512 class group action with the goal of, respectively, maximizing throughput and minimizing latency. We introduce different approaches for batching group actions and computing them in SIMD fashion on modern Intel processors. In particular, we present a hybrid batching technique that, when combined with optimized (8 × 1)-way prime-field arithmetic, increases the throughput by a factor of 3.64 compared to a state-of-the-art (non-vectorized) x64 implementation. On the other hand, vectorization in a 2-way fashion aimed to reduce latency makes our AVX-512 implementation of the group action evaluation about 1.54 times faster than the state-of-the-art. To the best of our knowledge, this paper is the first to demonstrate the high potential of using vector instructions to increase the throughput (resp. decrease the latency) of constant-time CSIDH. [less ▲]

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See detailSecure Transmission in Massive MIMO System with Specular Component-based Beamforming and Artificial Noise over Ricean Fading Channel
Qu, Aiyan; Zhang, Xianyu; An, Kang et al

in IEEE Wireless Communications Letters (2021), 10(11, Nov. 2021),

This paper investigates the secure transmission in a multi-user massive MIMO system over Ricean fading channel in the presence of a multi-antenna eavesdropper. In order to reduce the system complexity and ... [more ▼]

This paper investigates the secure transmission in a multi-user massive MIMO system over Ricean fading channel in the presence of a multi-antenna eavesdropper. In order to reduce the system complexity and the channel estimation overhead, a low-complexity beamforming (BF) scheme using only the specular component is presented. Moreover, the generation of artificial noise (AN) is employed at the base station (BS) for additional security enhancement. Specifically, a tractable closedform lower bound for the achievable ergodic secrecy rate is derived. Furthermore, the optimal power allocation factor is obtained based on the asymptotic analysis to maximize the achievable ergodic secrecy rate. The analytical results reveal that the ergodic secrecy rate improves with the increase of Ricean K- factor and converges to a specific constant when increasing the number of antennas. The performance of the proposed scheme is evaluated through comprehensive simulations. [less ▲]

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See detailOn the effects of income heterogeneity in monopolistically competitive markets”
Picard, Pierre M UL; Kichko, Sergey

Scientific Conference (2021, August)

This paper studies the e¤ects of income heterogeneity on monopolistically competitive product markets and welfare in the context of non-homothetic preferences. When richer individuals expenditures are ... [more ▼]

This paper studies the e¤ects of income heterogeneity on monopolistically competitive product markets and welfare in the context of non-homothetic preferences. When richer individuals expenditures are less sensitive to price change compared to poorer ones , a mean-preserving contraction of income distribution entices rms to charge higher prices, new rms enter and broaden product diversity. General equilibrium e¤ects have a negative impact on poorer individuals and, in speci c circumstances, on whole population. In open economies, lower income inequality in a country creates a price divergence between countries and decreases trade volumes and values. Those general equilibrium e¤ects are quantitatively non negligible. [less ▲]

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See detailMedienwissenschaften und Mediendidaktik im Dialog. Zum Status Quoe von Medienbildung im Deutschunterricht
Dembeck, Till UL; Pavlik, Jennifer

Book published by Erich Schmidt (2021)

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See detailCreativity in Humans, Robots, Humbots
Lubart, Todd; Esposito, Dario; Gubenko, Alla UL et al

in Creativity: Theories – Research – Applications (2021), 8(1),

Detailed reference viewed: 70 (16 UL)