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  • Publication . Article . Preprint . 2021
    Open Access English
    Authors: 
    Anat Ganor; C S Karthik; Dömötör Pálvölgyi;
    Project: EC | COMPECON (740282)

    Brouwer’s fixed point theorem states that any continuous function from a compact convex space to itself has a fixed point. Roughgarden and Weinstein (FOCS 2016) initiated the study of fixed point computation in the two-player communication model, where each player gets a function from [0,1]^n to [0,1]^n , and their goal is to find an approximate fixed point of the composition of the two functions. They left it as an open question to show a lower bound of 2^{\Omega (n)} for the (randomized) communication complexity of this problem, in the range of parameters which make it a total search problem. We answer this question affirmatively. Additionally, we introduce two natural fixed point problems in the two-player communication model. Each player is given a function from [0,1]^n to [0,1]^{n/2} , and their goal is to find an approximate fixed point of the concatenation of the functions. Each player is given a function from [0,1]^n to [0,1]^{n} , and their goal is to find an approximate fixed point of the mean of the functions. We show a randomized communication complexity lower bound of 2^{\Omega (n)} for these problems (for some constant approximation factor). Finally, we initiate the study of finding a panchromatic simplex in a Sperner-coloring of a triangulation (guaranteed by Sperner’s lemma) in the two-player communication model: A triangulation T of the d -simplex is publicly known and one player is given a set S_A\subset T and a coloring function from S_A to \lbrace 0,\ldots ,d/2\rbrace , and the other player is given a set S_B\subset T and a coloring function from S_B to \lbrace d/2+1,\ldots ,d\rbrace , such that S_A\dot{\cup }S_B=T , and their goal is to find a panchromatic simplex. We show a randomized communication complexity lower bound of |T|^{\Omega (1)} for the aforementioned problem as well (when d is large). On the positive side, we show that if d\le 4 then there is a deterministic protocol for the Sperner problem with O((\log |T|)^2) bits of communication.

  • Open Access English
    Authors: 
    Ayelet Gertsovski; Merav Ahissar;
    Publisher: Society for Neuroscience
    Project: EC | NeuroCompSkill (833694)

    A main characteristic of dyslexia is poor use of sound categories. We now studied within-session learning of new sound categories in dyslexia, behaviorally and neurally, using fMRI. Human participants (males and females) with and without dyslexia were asked to discriminate which of two serially-presented tones had a higher pitch. The task was administered in two protocols, with and without a repeated reference frequency. The reference condition introduces regularity, and enhances frequency sensitivity in typically developing (TD) individuals. Enhanced sensitivity facilitates the formation of “high” and “low” pitch categories above and below this reference, respectively. We found that in TDs, learning was paralleled by a gradual decrease in activation of the primary auditory cortex (PAC), and reduced activation of the superior temporal gyrus (STG) and left posterior parietal cortex (PPC), which are important for using sensory history. No such sensitivity was found among individuals with dyslexia (IDDs). Rather, IDDs showed reduced behavioral learning of stimulus regularities and no regularity-associated adaptation in the auditory cortex or in higher-level regions. We propose that IDDs' reduced cortical adaptation, associated with reduced behavioral learning of sound regularities, underlies their impoverished use of stimulus history, and consequently impedes their formation of rich sound categories. SIGNIFICANCE STATEMENT Reading difficulties in dyslexia are often attributed to poor use of phonological categories. To test whether poor category use could result from poor learning of new sound categories in general, we administered an auditory discrimination task that examined the learning of new pitch categories above and below a repeated reference sound. Individuals with dyslexia (IDDs) learned categories slower than typically developing (TD) individuals. TD individuals showed adaptation to the repeated sounds that paralleled the category learning in their primary auditory cortex (PAC) and other higher-level regions. In dyslexia, no brain region showed such adaptation. We suggest that poor learning of sound statistics in sensory regions may underlie the poor representations of both speech and nonspeech categories in dyslexia.

  • Publication . Article . Presentation . Other literature type . Conference object . Preprint . 2021
    Open Access English

    We investigate the special case of diamond relay comprising a Gaussian channel with identical frequency response from the user to the relays and fronthaul links with limited rate from the relays to the destination. We use the oblivious compress and forward (CF) with distributed compression and decode and forward (DF) where each relay decodes the whole message and sends half of its bits to the destination. We derive achievable rate by using time-sharing between DF and CF. It is proved that optimal CF-DF time sharing is advantageous over superposition of CF and DF. The optimal time sharing proportion between DF and CF and power and rate allocations are different at each frequency and are fully determined.

  • Open Access English
    Authors: 
    Shelly Meron; Yulia Shenberger; Sharon Ruthstein;
    Project: EC | CuHypMECH (754365)

    Electron paramagnetic resonance (EPR) spectroscopy has emerged as an ideal biophysical tool to study complex biological processes. EPR spectroscopy can follow minor conformational changes in various proteins as a function of ligand or protein binding or interactions with high resolution and sensitivity. Resolving cellular mechanisms, involving small ligand binding or metal ion transfer, is not trivial and cannot be studied using conventional biophysical tools. In recent years, our group has been using EPR spectroscopy to study the mechanism underlying copper ion transfer in eukaryotic and prokaryotic systems. This mini-review focuses on our achievements following copper metal coordination in the diamagnetic oxidation state, Cu(I), between biomolecules. We discuss the conformational changes induced in proteins upon Cu(I) binding, as well as the conformational changes induced in two proteins involved in Cu(I) transfer. We also consider how EPR spectroscopy, together with other biophysical and computational tools, can identify the Cu(I)-binding sites. This work describes the advantages of EPR spectroscopy for studying biological processes that involve small ligand binding and transfer between intracellular proteins.

  • Open Access English
    Authors: 
    Ignacio A. Lazagabaster; Natalia Égüez; Micka Ullman; Roi Porat; Ido Wachtel; Uri Davidovich; Nimrod Marom;
    Project: EC | DEADSEA_ECO (802752)

    Long temporal records of Holocene wild mammal communities are essential to examine the role of human impacts and climatic fluctuations in the configuration of modern ecosystems. We show that such records can be assembled through extensive radiocarbon dating of faunal remains obtained from biogenic cave deposits. We dated 110 mammalian remains from 19 different cave sites in the Judean Desert. We use the dates in combination with archaeological survey data and bone collagen/apatite δ13C values to study faunal succession in the context of Holocene climate change and human settlement history in the region. Our results suggest a change in the late Holocene, expressed in fewer observations of Arabian leopard (Panthera pardus nimr) and gazelle (Gazella spp.), and an increase of Syrian striped hyena (Hyaena hyaena syriaca), fox (Vulpes spp.), Nubian ibex (Capra nubiana) and rock hyrax (Procavia capensis); suids (Sus scrofa) appear for the first time. According to the data distribution, however, the probability of finding a bone diminishes exponentially with time, which implies that the Judean Desert cave paleozoological record is temporally biased. The weight of evidence ultimately favors an explanation of the observed patterns as the consequence of a combined anthropogenic and climatic impact on local food webs. H2020 European Research Council http://dx.doi.org/10.13039/100010663 Alexander von Humboldt‐Stiftung http://dx.doi.org/10.13039/100005156

  • Publication . Article . Preprint . 2021
    Open Access English
    Authors: 
    Miron Amusia; Arkadiy S. Baltenkov;

    In this paper we calculate the elastic scattering cross sections of slow electron by carbon nanotubes. The corresponding electron-nanotube interaction is substituted by a zero-thickness cylindrical potential that neglects the atomic structure of real nanotubes, thus limiting the range of applicability of our approach to sufficiently low incoming electron energies. The strength of the potential is chosen the same that was used in describing scattering of electrons by fullerene C60. We present results for total and partial electron scattering cross sections as well as respective angular distributions, all with account of five lowest angular momenta contributions. In the calculations we assumed that the incoming electron moves perpendicular to the nanotube axis, since along the axis the incoming electron moves freely. 10 pages, 2 figures

  • Publication . Article . Preprint . 2021
    Open Access English
    Authors: 
    Itai Benjamini; David Ellis;
    Country: United Kingdom

    We continue the study of the properties of graphs in which the ball of radius $r$ around each vertex induces a graph isomorphic to the ball of radius $r$ in some fixed vertex-transitive graph $F$, for various choices of $F$ and $r$. This is a natural extension of the study of regular graphs. More precisely, if $F$ is a vertex-transitive graph and $r \in \mathbb{N}$, we say a graph $G$ is {\em $r$-locally $F$} if the ball of radius $r$ around each vertex of $G$ induces a graph isomorphic to the graph induced by the ball of radius $r$ around any vertex of $F$. We consider the following random graph model: for each $n \in \mathbb{N}$, we let $G_n = G_n(F,r)$ be a graph chosen uniformly at random from the set of all unlabelled, $n$-vertex graphs that are $r$-locally $F$. We investigate the properties possessed by the random graph $G_n$ with high probability, for various natural choices of $F$ and $r$. We prove that if $F$ is a Cayley graph of a torsion-free group of polynomial growth, and $r$ is sufficiently large depending on $F$, then the random graph $G_n = G_n(F,r)$ has largest component of order at most $n^{5/6}$ with high probability, and has at least $\exp(n^{\delta})$ automorphisms with high probability, where $\delta>0$ depends upon $F$ alone. Both properties are in stark contrast to random $d$-regular graphs, which correspond to the case where $F$ is the infinite $d$-regular tree. We also show that, under the same hypotheses, the number of unlabelled, $n$-vertex graphs that are $r$-locally $F$ grows like a stretched exponential in $n$, again in contrast with $d$-regular graphs. In the case where $F$ is the standard Cayley graph of $\mathbb{Z}^d$, we obtain a much more precise enumeration result, and more precise results on the properties of the random graph $G_n(F,r)$. Our proofs use a mixture of results and techniques from geometry, group theory and combinatorics. Comment: Full proof of Theorem 7 added. Statement of Proposition 38 has been strengthened slightly. 61 pages

  • Open Access English
    Authors: 
    Homa Nikbakht; Michele Wigger; Shlomo Shamai;
    Publisher: Zenodo
    Project: EC | CloudRadioNet (694630), EC | CTO Com (715111)

    This paper analyzes the multiplexing gains (MG) for simultaneous transmission of delay-sensitive and delay-tolerant data over interference networks. In the considered model, only delay-tolerant data can profit from coordinated multipoint (CoMP) transmission or reception techniques, because delay-sensitive data has to be transmitted without further delay. Transmission of delay-tolerant data is also subject to a delay constraint, which is however less stringent than the one on delay-sensitive data. Different coding schemes are proposed, and the corresponding MG pairs for delay-sensitive and delay-tolerant data are characterized for Wyner's linear symmetric network and for Wyner's two-dimensional hexagonal network with and without sectorization. For Wyner's linear symmetric also an information-theoretic converse is established and shown to be exact whenever the cooperation rates are sufficiently large or the delay-sensitive MG is small or moderate. These results show that on Wyner's symmetric linear network and for sufficiently large cooperation rates, the largest MG for delay-sensitive data can be achieved without penalizing the maximum sum-MG of both delay-sensitive and delay-tolerant data. A similar conclusion holds for Wyner's hexagonal network only for the model with sectorization. In the model without sectorization, a penalty in sum-MG is incurred whenever one insists on a positive delay-sensitive MG. 41 pages, submitted to Transactions on Communications

  • Open Access English
    Authors: 
    André O. Werneck; Miguel Peralta; Riki Tesler; Adilson Marques;
    Publisher: Elsevier
    Country: Portugal

    Objectives: To investigate the cross-sectional and prospective associations of lifestyle risk behaviors clustering with elevated depressive symptoms and to explore synergic prospective associations of different combinations of lifestyle risk behaviors with subsequent depressive symptoms. Study design: Prospective cohort study. Data on 31,190 middle-aged and older adults from waves 4 (2011) and 6 (2015) of the Survey of Health, Ageing and Retirement in Europe (SHARE) were used. Main outcome measures: Elevated depressive symptoms were estimated using the EURO-D 12-item scale. Lifestyle risk behaviors composing the cluster included physical inactivity, inadequate consumption of fruit and/or vegetables, binge drinking, and tobacco smoking. Gender, age group, education, place of residence, country, number of chronic diseases and body mass index were considered as confounders. Results: With the exception of binge drinking, all lifestyle risk behaviors were associated with higher odds of elevated depressive symptoms in cross-sectional and prospective analyses. The clustering of unhealthy lifestyle behaviors was cross-sectionally associated with elevated depressive symptoms and the clustering of two [odds ratio [OR]: 1.39; 95%CI: 1.28-1.51) and three or four (OR: 1.60; 95%CI: 1.38-1.85) were prospectively associated with elevated depressive symptoms. There were no interactions between the pairs of behaviors in the association with later elevated depressive symptoms. Conclusions: Our findings support the need for interventions integrating multiple health behaviors to prevent elevated depressive symptoms among middle-aged and older adults. This paper uses data from SHARE Waves 4, and 6 (DOIs: 10.6103/SHARE.w4.710 and 10.6103/SHARE.w6.710), see Börsch-Supan et al. (2013) for methodological details. The SHARE data collection has been funded by the European Commission, DG RTD through FP5 (QLK6-CT-2001-00360), FP6 (SHARE-I3: RII-CT-2006-062193, COMPARE: CIT5-CT-2005-028857, SHARELIFE: CIT4-CT-2006-028812), FP7 (SHARE-PREP: GA N°211909, SHARE-LEAP: GA N°227822, SHARE M4: GA N°261982, DASISH: GA N°283646) and Horizon 2020 (SHARE-DEV3: GA N°676536, SHARE-COHESION: GA N°870628, SERISS: GA N°654221, SSHOC: GA N°823782) and by DG Employment, Social Affairs & Inclusion through VS 2015/0195, VS 2016/0135, VS 2018/0285, VS 2019/0332, and VS 2020/0313. Additional funding from the German Ministry of Education and Research, the Max Planck Society for the Advancement of Science, the U.S. National Institute on Aging (U01_AG09740-13S2, P01_AG005842, P01_AG08291, P30_AG12815, R21_AG025169, Y1-AG-4553-01, IAG_BSR06-11, OGHA_04-064, HHSN271201300071C, RAG052527A) and from various national funding sources is gratefully acknowledged (see www.share-project.org). © 2021 Elsevier B.V. All rights reserved.

  • Publication . Article . Other literature type . Preprint . 2021
    Open Access English
    Authors: 
    Marco Piccardo; Vincent Ginis; Andrew Forbes; Simon Mahler; Haoran Ren; Ahmed H. Dorrah; Firehun Tsige Dullo; Antonio Ambrosio; Sylvain Gigan; Markus Hiekkamäki; +28 more
    Publisher: IOP Publishing
    Country: Switzerland
    Project: EC | CHIC (724344), NSERC , NSF | NNCI: The Center for Nano... (1541959), FCT | UIDB/50008/2020 (UIDB/50008/2020)

    Our ability to generate new distributions of light has been remarkably enhanced in recent years. At the most fundamental level, these light patterns are obtained by ingeniously combining different electromagnetic modes. Interestingly, the modal superposition occurs in the spatial, temporal as well as spatio-temporal domain. This generalized concept of structured light is being applied across the entire spectrum of optics: generating classical and quantum states of light, harnessing linear and nonlinear light-matter interactions, and advancing applications in microscopy, spectroscopy, holography, communication, and synchronization. This Roadmap highlights the common roots of these different techniques and thus establishes links between research areas that complement each other seamlessly. We provide an overview of all these areas, their backgrounds, current research, and future developments. We highlight the power of multimodal light manipulation and want to inspire new eclectic approaches in this vibrant research community. Under review in J. Opt

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44,114 Research products, page 1 of 4,412
  • Publication . Article . Preprint . 2021
    Open Access English
    Authors: 
    Anat Ganor; C S Karthik; Dömötör Pálvölgyi;
    Project: EC | COMPECON (740282)

    Brouwer’s fixed point theorem states that any continuous function from a compact convex space to itself has a fixed point. Roughgarden and Weinstein (FOCS 2016) initiated the study of fixed point computation in the two-player communication model, where each player gets a function from [0,1]^n to [0,1]^n , and their goal is to find an approximate fixed point of the composition of the two functions. They left it as an open question to show a lower bound of 2^{\Omega (n)} for the (randomized) communication complexity of this problem, in the range of parameters which make it a total search problem. We answer this question affirmatively. Additionally, we introduce two natural fixed point problems in the two-player communication model. Each player is given a function from [0,1]^n to [0,1]^{n/2} , and their goal is to find an approximate fixed point of the concatenation of the functions. Each player is given a function from [0,1]^n to [0,1]^{n} , and their goal is to find an approximate fixed point of the mean of the functions. We show a randomized communication complexity lower bound of 2^{\Omega (n)} for these problems (for some constant approximation factor). Finally, we initiate the study of finding a panchromatic simplex in a Sperner-coloring of a triangulation (guaranteed by Sperner’s lemma) in the two-player communication model: A triangulation T of the d -simplex is publicly known and one player is given a set S_A\subset T and a coloring function from S_A to \lbrace 0,\ldots ,d/2\rbrace , and the other player is given a set S_B\subset T and a coloring function from S_B to \lbrace d/2+1,\ldots ,d\rbrace , such that S_A\dot{\cup }S_B=T , and their goal is to find a panchromatic simplex. We show a randomized communication complexity lower bound of |T|^{\Omega (1)} for the aforementioned problem as well (when d is large). On the positive side, we show that if d\le 4 then there is a deterministic protocol for the Sperner problem with O((\log |T|)^2) bits of communication.

  • Open Access English
    Authors: 
    Ayelet Gertsovski; Merav Ahissar;
    Publisher: Society for Neuroscience
    Project: EC | NeuroCompSkill (833694)

    A main characteristic of dyslexia is poor use of sound categories. We now studied within-session learning of new sound categories in dyslexia, behaviorally and neurally, using fMRI. Human participants (males and females) with and without dyslexia were asked to discriminate which of two serially-presented tones had a higher pitch. The task was administered in two protocols, with and without a repeated reference frequency. The reference condition introduces regularity, and enhances frequency sensitivity in typically developing (TD) individuals. Enhanced sensitivity facilitates the formation of “high” and “low” pitch categories above and below this reference, respectively. We found that in TDs, learning was paralleled by a gradual decrease in activation of the primary auditory cortex (PAC), and reduced activation of the superior temporal gyrus (STG) and left posterior parietal cortex (PPC), which are important for using sensory history. No such sensitivity was found among individuals with dyslexia (IDDs). Rather, IDDs showed reduced behavioral learning of stimulus regularities and no regularity-associated adaptation in the auditory cortex or in higher-level regions. We propose that IDDs' reduced cortical adaptation, associated with reduced behavioral learning of sound regularities, underlies their impoverished use of stimulus history, and consequently impedes their formation of rich sound categories. SIGNIFICANCE STATEMENT Reading difficulties in dyslexia are often attributed to poor use of phonological categories. To test whether poor category use could result from poor learning of new sound categories in general, we administered an auditory discrimination task that examined the learning of new pitch categories above and below a repeated reference sound. Individuals with dyslexia (IDDs) learned categories slower than typically developing (TD) individuals. TD individuals showed adaptation to the repeated sounds that paralleled the category learning in their primary auditory cortex (PAC) and other higher-level regions. In dyslexia, no brain region showed such adaptation. We suggest that poor learning of sound statistics in sensory regions may underlie the poor representations of both speech and nonspeech categories in dyslexia.

  • Publication . Article . Presentation . Other literature type . Conference object . Preprint . 2021
    Open Access English

    We investigate the special case of diamond relay comprising a Gaussian channel with identical frequency response from the user to the relays and fronthaul links with limited rate from the relays to the destination. We use the oblivious compress and forward (CF) with distributed compression and decode and forward (DF) where each relay decodes the whole message and sends half of its bits to the destination. We derive achievable rate by using time-sharing between DF and CF. It is proved that optimal CF-DF time sharing is advantageous over superposition of CF and DF. The optimal time sharing proportion between DF and CF and power and rate allocations are different at each frequency and are fully determined.

  • Open Access English
    Authors: 
    Shelly Meron; Yulia Shenberger; Sharon Ruthstein;
    Project: EC | CuHypMECH (754365)

    Electron paramagnetic resonance (EPR) spectroscopy has emerged as an ideal biophysical tool to study complex biological processes. EPR spectroscopy can follow minor conformational changes in various proteins as a function of ligand or protein binding or interactions with high resolution and sensitivity. Resolving cellular mechanisms, involving small ligand binding or metal ion transfer, is not trivial and cannot be studied using conventional biophysical tools. In recent years, our group has been using EPR spectroscopy to study the mechanism underlying copper ion transfer in eukaryotic and prokaryotic systems. This mini-review focuses on our achievements following copper metal coordination in the diamagnetic oxidation state, Cu(I), between biomolecules. We discuss the conformational changes induced in proteins upon Cu(I) binding, as well as the conformational changes induced in two proteins involved in Cu(I) transfer. We also consider how EPR spectroscopy, together with other biophysical and computational tools, can identify the Cu(I)-binding sites. This work describes the advantages of EPR spectroscopy for studying biological processes that involve small ligand binding and transfer between intracellular proteins.

  • Open Access English
    Authors: 
    Ignacio A. Lazagabaster; Natalia Égüez; Micka Ullman; Roi Porat; Ido Wachtel; Uri Davidovich; Nimrod Marom;
    Project: EC | DEADSEA_ECO (802752)

    Long temporal records of Holocene wild mammal communities are essential to examine the role of human impacts and climatic fluctuations in the configuration of modern ecosystems. We show that such records can be assembled through extensive radiocarbon dating of faunal remains obtained from biogenic cave deposits. We dated 110 mammalian remains from 19 different cave sites in the Judean Desert. We use the dates in combination with archaeological survey data and bone collagen/apatite δ13C values to study faunal succession in the context of Holocene climate change and human settlement history in the region. Our results suggest a change in the late Holocene, expressed in fewer observations of Arabian leopard (Panthera pardus nimr) and gazelle (Gazella spp.), and an increase of Syrian striped hyena (Hyaena hyaena syriaca), fox (Vulpes spp.), Nubian ibex (Capra nubiana) and rock hyrax (Procavia capensis); suids (Sus scrofa) appear for the first time. According to the data distribution, however, the probability of finding a bone diminishes exponentially with time, which implies that the Judean Desert cave paleozoological record is temporally biased. The weight of evidence ultimately favors an explanation of the observed patterns as the consequence of a combined anthropogenic and climatic impact on local food webs. H2020 European Research Council http://dx.doi.org/10.13039/100010663 Alexander von Humboldt‐Stiftung http://dx.doi.org/10.13039/100005156

  • Publication . Article . Preprint . 2021
    Open Access English
    Authors: 
    Miron Amusia; Arkadiy S. Baltenkov;

    In this paper we calculate the elastic scattering cross sections of slow electron by carbon nanotubes. The corresponding electron-nanotube interaction is substituted by a zero-thickness cylindrical potential that neglects the atomic structure of real nanotubes, thus limiting the range of applicability of our approach to sufficiently low incoming electron energies. The strength of the potential is chosen the same that was used in describing scattering of electrons by fullerene C60. We present results for total and partial electron scattering cross sections as well as respective angular distributions, all with account of five lowest angular momenta contributions. In the calculations we assumed that the incoming electron moves perpendicular to the nanotube axis, since along the axis the incoming electron moves freely. 10 pages, 2 figures

  • Publication . Article . Preprint . 2021
    Open Access English
    Authors: 
    Itai Benjamini; David Ellis;
    Country: United Kingdom

    We continue the study of the properties of graphs in which the ball of radius $r$ around each vertex induces a graph isomorphic to the ball of radius $r$ in some fixed vertex-transitive graph $F$, for various choices of $F$ and $r$. This is a natural extension of the study of regular graphs. More precisely, if $F$ is a vertex-transitive graph and $r \in \mathbb{N}$, we say a graph $G$ is {\em $r$-locally $F$} if the ball of radius $r$ around each vertex of $G$ induces a graph isomorphic to the graph induced by the ball of radius $r$ around any vertex of $F$. We consider the following random graph model: for each $n \in \mathbb{N}$, we let $G_n = G_n(F,r)$ be a graph chosen uniformly at random from the set of all unlabelled, $n$-vertex graphs that are $r$-locally $F$. We investigate the properties possessed by the random graph $G_n$ with high probability, for various natural choices of $F$ and $r$. We prove that if $F$ is a Cayley graph of a torsion-free group of polynomial growth, and $r$ is sufficiently large depending on $F$, then the random graph $G_n = G_n(F,r)$ has largest component of order at most $n^{5/6}$ with high probability, and has at least $\exp(n^{\delta})$ automorphisms with high probability, where $\delta>0$ depends upon $F$ alone. Both properties are in stark contrast to random $d$-regular graphs, which correspond to the case where $F$ is the infinite $d$-regular tree. We also show that, under the same hypotheses, the number of unlabelled, $n$-vertex graphs that are $r$-locally $F$ grows like a stretched exponential in $n$, again in contrast with $d$-regular graphs. In the case where $F$ is the standard Cayley graph of $\mathbb{Z}^d$, we obtain a much more precise enumeration result, and more precise results on the properties of the random graph $G_n(F,r)$. Our proofs use a mixture of results and techniques from geometry, group theory and combinatorics. Comment: Full proof of Theorem 7 added. Statement of Proposition 38 has been strengthened slightly. 61 pages

  • Open Access English
    Authors: 
    Homa Nikbakht; Michele Wigger; Shlomo Shamai;
    Publisher: Zenodo
    Project: EC | CloudRadioNet (694630), EC | CTO Com (715111)

    This paper analyzes the multiplexing gains (MG) for simultaneous transmission of delay-sensitive and delay-tolerant data over interference networks. In the considered model, only delay-tolerant data can profit from coordinated multipoint (CoMP) transmission or reception techniques, because delay-sensitive data has to be transmitted without further delay. Transmission of delay-tolerant data is also subject to a delay constraint, which is however less stringent than the one on delay-sensitive data. Different coding schemes are proposed, and the corresponding MG pairs for delay-sensitive and delay-tolerant data are characterized for Wyner's linear symmetric network and for Wyner's two-dimensional hexagonal network with and without sectorization. For Wyner's linear symmetric also an information-theoretic converse is established and shown to be exact whenever the cooperation rates are sufficiently large or the delay-sensitive MG is small or moderate. These results show that on Wyner's symmetric linear network and for sufficiently large cooperation rates, the largest MG for delay-sensitive data can be achieved without penalizing the maximum sum-MG of both delay-sensitive and delay-tolerant data. A similar conclusion holds for Wyner's hexagonal network only for the model with sectorization. In the model without sectorization, a penalty in sum-MG is incurred whenever one insists on a positive delay-sensitive MG. 41 pages, submitted to Transactions on Communications

  • Open Access English
    Authors: 
    André O. Werneck; Miguel Peralta; Riki Tesler; Adilson Marques;
    Publisher: Elsevier
    Country: Portugal

    Objectives: To investigate the cross-sectional and prospective associations of lifestyle risk behaviors clustering with elevated depressive symptoms and to explore synergic prospective associations of different combinations of lifestyle risk behaviors with subsequent depressive symptoms. Study design: Prospective cohort study. Data on 31,190 middle-aged and older adults from waves 4 (2011) and 6 (2015) of the Survey of Health, Ageing and Retirement in Europe (SHARE) were used. Main outcome measures: Elevated depressive symptoms were estimated using the EURO-D 12-item scale. Lifestyle risk behaviors composing the cluster included physical inactivity, inadequate consumption of fruit and/or vegetables, binge drinking, and tobacco smoking. Gender, age group, education, place of residence, country, number of chronic diseases and body mass index were considered as confounders. Results: With the exception of binge drinking, all lifestyle risk behaviors were associated with higher odds of elevated depressive symptoms in cross-sectional and prospective analyses. The clustering of unhealthy lifestyle behaviors was cross-sectionally associated with elevated depressive symptoms and the clustering of two [odds ratio [OR]: 1.39; 95%CI: 1.28-1.51) and three or four (OR: 1.60; 95%CI: 1.38-1.85) were prospectively associated with elevated depressive symptoms. There were no interactions between the pairs of behaviors in the association with later elevated depressive symptoms. Conclusions: Our findings support the need for interventions integrating multiple health behaviors to prevent elevated depressive symptoms among middle-aged and older adults. This paper uses data from SHARE Waves 4, and 6 (DOIs: 10.6103/SHARE.w4.710 and 10.6103/SHARE.w6.710), see Börsch-Supan et al. (2013) for methodological details. The SHARE data collection has been funded by the European Commission, DG RTD through FP5 (QLK6-CT-2001-00360), FP6 (SHARE-I3: RII-CT-2006-062193, COMPARE: CIT5-CT-2005-028857, SHARELIFE: CIT4-CT-2006-028812), FP7 (SHARE-PREP: GA N°211909, SHARE-LEAP: GA N°227822, SHARE M4: GA N°261982, DASISH: GA N°283646) and Horizon 2020 (SHARE-DEV3: GA N°676536, SHARE-COHESION: GA N°870628, SERISS: GA N°654221, SSHOC: GA N°823782) and by DG Employment, Social Affairs & Inclusion through VS 2015/0195, VS 2016/0135, VS 2018/0285, VS 2019/0332, and VS 2020/0313. Additional funding from the German Ministry of Education and Research, the Max Planck Society for the Advancement of Science, the U.S. National Institute on Aging (U01_AG09740-13S2, P01_AG005842, P01_AG08291, P30_AG12815, R21_AG025169, Y1-AG-4553-01, IAG_BSR06-11, OGHA_04-064, HHSN271201300071C, RAG052527A) and from various national funding sources is gratefully acknowledged (see www.share-project.org). © 2021 Elsevier B.V. All rights reserved.

  • Publication . Article . Other literature type . Preprint . 2021
    Open Access English
    Authors: 
    Marco Piccardo; Vincent Ginis; Andrew Forbes; Simon Mahler; Haoran Ren; Ahmed H. Dorrah; Firehun Tsige Dullo; Antonio Ambrosio; Sylvain Gigan; Markus Hiekkamäki; +28 more
    Publisher: IOP Publishing
    Country: Switzerland
    Project: EC | CHIC (724344), NSERC , NSF | NNCI: The Center for Nano... (1541959), FCT | UIDB/50008/2020 (UIDB/50008/2020)

    Our ability to generate new distributions of light has been remarkably enhanced in recent years. At the most fundamental level, these light patterns are obtained by ingeniously combining different electromagnetic modes. Interestingly, the modal superposition occurs in the spatial, temporal as well as spatio-temporal domain. This generalized concept of structured light is being applied across the entire spectrum of optics: generating classical and quantum states of light, harnessing linear and nonlinear light-matter interactions, and advancing applications in microscopy, spectroscopy, holography, communication, and synchronization. This Roadmap highlights the common roots of these different techniques and thus establishes links between research areas that complement each other seamlessly. We provide an overview of all these areas, their backgrounds, current research, and future developments. We highlight the power of multimodal light manipulation and want to inspire new eclectic approaches in this vibrant research community. Under review in J. Opt

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