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See detailRare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease
Sims, Rebecca; van der Lee, Sven J.; Naj, Adam C. et al

in Nature Genetics (2017), 49

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See detailRare GABRA3 variants are associated with epileptic seizures, encephalopathy and dysmorphic features
Niturad, Elena Christina; Lev, Dorit; Kalscheuer, Vera M et al

in Brain : A Journal of Neurology (2017), 140(11), 2879-2894

Genetic epilepsies are caused by mutations in a range of different genes, many of them encoding ion channels, receptors or transporters. While the number of detected variants and genes increased ... [more ▼]

Genetic epilepsies are caused by mutations in a range of different genes, many of them encoding ion channels, receptors or transporters. While the number of detected variants and genes increased dramatically in the recent years, pleiotropic effects have also been recognized, revealing that clinical syndromes with various degrees of severity arise from a single gene, a single mutation, or from different mutations showing similar functional defects. Accordingly, several genes coding for GABAA receptor subunits have been linked to a spectrum of benign to severe epileptic disorders and it was shown that a loss of function presents the major correlated pathomechanism. Here, we identified six variants in GABRA3 encoding the α3-subunit of the GABAA receptor. This gene is located on chromosome Xq28 and has not been previously associated with human disease. Five missense variants and one microduplication were detected in four families and two sporadic cases presenting with a range of epileptic seizure types, a varying degree of intellectual disability and developmental delay, sometimes with dysmorphic features or nystagmus. The variants co-segregated mostly but not completely with the phenotype in the families, indicating in some cases incomplete penetrance, involvement of other genes, or presence of phenocopies. Overall, males were more severely affected and there were three asymptomatic female mutation carriers compared to only one male without a clinical phenotype. X-chromosome inactivation studies could not explain the phenotypic variability in females. Three detected missense variants are localized in the extracellular GABA-binding NH2-terminus, one in the M2-M3 linker and one in the M4 transmembrane segment of the α3-subunit. Functional studies in Xenopus laevis oocytes revealed a variable but significant reduction of GABA-evoked anion currents for all mutants compared to wild-type receptors. The degree of current reduction correlated partially with the phenotype. The microduplication disrupted GABRA3 expression in fibroblasts of the affected patient. In summary, our results reveal that rare loss-of-function variants in GABRA3 increase the risk for a varying combination of epilepsy, intellectual disability/developmental delay and dysmorphic features, presenting in some pedigrees with an X-linked inheritance pattern. [less ▲]

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See detailRare gene deletions in genetic generalized and Rolandic epilepsies
Jabbari, Kamel; Bobbili, Dheeraj Reddy UL; Lal, Dennis et al

in PLoS ONE (2018)

Genetic Generalized Epilepsy (GGE) and benign epilepsy with centro-temporal spikes or Rolandic Epilepsy (RE) are common forms of genetic epilepsies. Rare copy number variants have been recognized as ... [more ▼]

Genetic Generalized Epilepsy (GGE) and benign epilepsy with centro-temporal spikes or Rolandic Epilepsy (RE) are common forms of genetic epilepsies. Rare copy number variants have been recognized as important risk factors in brain disorders. We performed a systematic survey of rare deletions affecting protein-coding genes derived from exome data of patients with common forms of genetic epilepsies. We analysed exomes from 390 European patients (196 GGE and 194 RE) and 572 population controls to identify low-frequency genic deletions. We found that 75 (32 GGE and 43 RE) patients out of 390, i.e. ~19%, carried rare genic deletions. In particular, large deletions (>400 kb) represent a higher burden in both GGE and RE syndromes as compared to controls. The detected low-frequency deletions (1) share genes with brain-expressed exons that are under negative selection, (2) overlap with known autism and epilepsy-associated candidate genes, (3) are enriched for CNV intolerant genes recorded by the Exome Aggregation Consortium (ExAC) and (4) coincide with likely disruptive de novo mutations from the NPdenovo database. Employing several knowledge databases, we discuss the most prominent epilepsy candidate genes and their protein-protein networks for GGE and RE. [less ▲]

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See detailA rare loss-of function variant of ADAM17 is associated with late-onset familial Alzheimer disease
Hartl, Daniela; May, Patrick UL; Gu, Wei UL et al

in Molecular Psychiatry (2020), 25(3), 629-639

Common variants of about 20 genes contributing to AD risk have so far been identified through genome-wide association studies (GWAS). However, there is still a large proportion of heritability that might ... [more ▼]

Common variants of about 20 genes contributing to AD risk have so far been identified through genome-wide association studies (GWAS). However, there is still a large proportion of heritability that might be explained by rare but functionally important variants. One of the so far identified genes with rare AD causing variants is ADAM10. Using whole-genome sequencing we now identified a single rare nonsynonymous variant (SNV) rs142946965 [p.R215I] in ADAM17 co-segregating with an autosomal-dominant pattern of late-onset AD in one family. Subsequent genotyping and analysis of available whole-exome sequencing data of additional case/control samples from Germany, the UK and the USA identified five variant carriers among AD patients only. The mutation inhibits pro-protein cleavage and the formation of the active enzyme, thus leading to loss-of-function of ADAM17 α-secretase. Further, we identified a strong negative correlation between ADAM17 and APP gene expression in human brain and present in vitro evidence that ADAM17 negatively controls the expression of APP. As a consequence, p.R215I mutation of ADAM17 leads to elevated Aß formation in vitro. Together our data supports a causative association of the identified ADAM17 variant in the pathogenesis of AD. [less ▲]

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See detailRare variant analysis of the PPMI dataset to uncover the complex genetic architecture of Parkinson’s disease
Bobbili, Dheeraj Reddy UL; May, Patrick UL; Krüger, Rejko UL

in Movement Disorders (2017, June 02), 322(Supplement S2), 405

Objective: To unravel the genetic factors that play a role in PD we used the whole exome sequencing data available as a part of Parkinson Progression Markers Initiative (PPMI). Background: Parkinson’s ... [more ▼]

Objective: To unravel the genetic factors that play a role in PD we used the whole exome sequencing data available as a part of Parkinson Progression Markers Initiative (PPMI). Background: Parkinson’s disease (PD) is a complex disease. Besides variants in high-risk genes such as LRRK2 and PARK2, multiple genes associated to sporadic PD were discovered via genome-wide association studies. Yet, there is a large number of genetic factors that need to be deciphered. Methods: To unravel the genetic factors that play a role in PD we used the whole exome sequencing data available as a part of Parkinson Progression Markers Initiative (PPMI). The dataset comprised of 435 PD cases and 162 ethnically matched controls, respectively. We performed burden tests at single variant, gene and geneset levels on common and rare exonic and splice-variants. We also looked for severity of rare highly deleterious variants (CADD phred score>30) using the CADD score as well as singleton (variants seen in only one individual across cases and controls) rare variants. Additionally, we performed the functional enrichment analysis with the genes harboring rare highly deleterious variants (case uniq genes) that are only present in cases. Results: We observed an increased mutational burden of singleton variants in PD cases compared to the controls in nonsynonymous+LOF variants (empirical P-value 0.005) but not in the synonymous variants (empirical P-value 0.09). We observed a higher significant burden (P-value 0.028) as well as higher significant severity (empirical P-value 0.027) of rare, highly deleterious nonsynonymous variants, but not in the synonymous variants of the candidate genes (P-value 0.686, empirical P-value 0.556 for burden and severity respectively). The network analysis of genes having deleterious variants only present in cases (Case uniq) showed a significant increase in connectivity compared to random networks (P-value 0.0002). Pathway analysis of those genes showed a significant enrichment of pathways and biological process implicated in the nervous system functioning and the etiology of PD. Conclusions: Our study supports the complex disease notion of PD by highlighting the convoluted architecture of PD where case uniq genes including LRRK2 are implicated in several biological processes and pathways related to PD. The main finding of this study is to discover the complex genetics of PD at an exome wide level. [less ▲]

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See detailRare-earth nickelates RNiO3: thin films and heterostructures
Catalano, S.; Gibert, M.; Fowlie, J. et al

in REPORTS ON PROGRESS IN PHYSICS (2018), 81(4),

This review stands in the larger framework of functional materials by focussing on heterostructures of rare-earth nickelates, described by the La, Pr, Nd Sm,., Lu. Nickelates are characterized by a rich ... [more ▼]

This review stands in the larger framework of functional materials by focussing on heterostructures of rare-earth nickelates, described by the La, Pr, Nd Sm,., Lu. Nickelates are characterized by a rich phase diagram of structural and physical properties and serve as a benchmark for the physics of phase transitions in correlated oxides where electron-lattice coupling plays a key role. Much of the recent interest in nickelates concerns heterostructures, that is single layers of thin film multilayers or superlattices, with the general objective of modulating their physical properties through strain control, confinement or interface effects. We will discuss the extensive studies on nickelate heterostructures as well as outline different approaches to tuning and controlling their physical properties and, finally, review application concepts for future devices. [less ▲]

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See detailRas-association domain family member 1A (RASSF1A)-where the heart and cancer meet.
Oceandy, Delvac; Cartwright, Elizabeth J.; Neyses, Ludwig UL

in Trends in cardiovascular medicine (2009), 19(8), 262-7

The close relationship between signaling pathways regulating tumor growth and cardiac hypertrophy has attracted considerable interest. Although the involvement of proto-oncogenes in positively modulating ... [more ▼]

The close relationship between signaling pathways regulating tumor growth and cardiac hypertrophy has attracted considerable interest. Although the involvement of proto-oncogenes in positively modulating myocardial hypertrophy has long been recognized, little is known about factors that counterregulate them. In this article, we review the novel tumor suppressor Ras-association domain family protein isoform 1A (RASSF1A), which strongly inhibits the prohypertrophic Ras-Raf1-ERK1/2 pathway in the heart. RASSF1A interacts with a number of important signaling molecules regulating cell growth, survival, and apoptosis; therefore, it serves as a key adaptor molecule that integrates the upstream stimuli and transduces them to the selective downstream effectors. [less ▲]

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See detailRasche, nicht-genomische Effekte von minimalen Cortisoldosen auf die Baroreflexkontrolle der Herzrate
Richter, S.; Schulz, André UL; Oitzl, M. S. et al

in Widmann, A.; Andersen, S. K.; Friederici, A. D. (Eds.) et al 35. Arbeitstagung Psychophysiologie und Methodik (2009)

Detailed reference viewed: 95 (0 UL)
See detailRassismus an Diskriminatioun
Santana, Dominique UL

Speeches/Talks (2018)

Detailed reference viewed: 97 (8 UL)
See detailDie rassismussensible Schule - ein Vorwort
Böhmer, Matthias UL; Steffgen, Georges UL

in Böhmer, Matthias; Steffgen, Georges (Eds.) Rassismus an Schulen - Geschichte, Erklärungen, Auswirkungen und Interventionsansätze (2022)

Detailed reference viewed: 56 (1 UL)
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See detailRAT 2.0
Höhn, Winfried UL; Schommer, Christoph UL

in Digital Humanities 2017: Conference Abstracts (2017)

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See detailRAT: A Referencing and Annotation Tool for Digitized Early Maps
Höhn, Winfried UL; Schommer, Christoph UL

Scientific Conference (2016, June)

RAT is designed to support users in identifying place markers in digitised early maps and to link these place markers to modern maps. RAT facilitates a geo-referencing by suggesting the most likely modern ... [more ▼]

RAT is designed to support users in identifying place markers in digitised early maps and to link these place markers to modern maps. RAT facilitates a geo-referencing by suggesting the most likely modern places based on an estimated mapping and a phonetic search for place names. [less ▲]

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See detailRate of Convergence for Discretization of Integrals with Respect to Fractional Brownian Motion
Azmoodeh, Ehsan UL; Viitasaari, Lauri

in Journal of Theoretical Probability (2013)

In this article, an uniform discretization of stochastic integrals $\int_{0}^{1} f'_-(B_t)\ud B_t$, where $B_t$ denotes the fractional Brownian motion with Hurst parameter $H \in (\frac{1}{2},1)$, for a ... [more ▼]

In this article, an uniform discretization of stochastic integrals $\int_{0}^{1} f'_-(B_t)\ud B_t$, where $B_t$ denotes the fractional Brownian motion with Hurst parameter $H \in (\frac{1}{2},1)$, for a large class of convex functions $f$ is considered. In $\big[$\cite{a-m-v}, Statistics \& Decisions, \textbf{27}, 129-143$\big]$, for any convex function $f$, the almost sure convergence of uniform discretization to such stochastic integral is proved. Here we prove $L^r$- convergence of uniform discretization to stochastic integral. In addition, we obtain a rate of convergence. It turns out that the rate of convergence can be brought arbitrary close to $H - \frac{1}{2}$. [less ▲]

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See detailRate of estimation for the stationary distribution of jump-processes over anisotropic Holder classes.
Amorino, Chiara UL

E-print/Working paper (2020)

We study the problem of the non-parametric estimation for the density π of the stationary distribution of the multivariate stochastic differential equation with jumps (Xt)0≤t≤T , when the dimension d is ... [more ▼]

We study the problem of the non-parametric estimation for the density π of the stationary distribution of the multivariate stochastic differential equation with jumps (Xt)0≤t≤T , when the dimension d is such that d ≥ 3. From the continuous observa- tion of the sampling path on [0, T ] we show that, under anisotropic H ̈older smoothness constraints, kernel based estimators can achieve fast convergence rates. In particu- lar, they are as fast as the ones found by Dalalyan and Reiss [9] for the estimation of the invariant density in the case without jumps under isotropic H ̈older smooth- ness constraints. Moreover, they are faster than the ones found by Strauch [29] for the invariant density estimation of continuous stochastic differential equations, under anisotropic H ̈older smoothness constraints. Furthermore, we obtain a minimax lower bound on the L2-risk for pointwise estimation, with the same rate up to a log(T) term. It implies that, on a class of diffusions whose invariant density belongs to the anisotropic Holder class we are considering, it is impossible to find an estimator with a rate of estimation faster than the one we propose. [less ▲]

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See detailRate optimization for massive MIMO relay networks: A minorization-maximization approach
Naghsh, M.M.; Soltanalian, M.; Stoica, P. et al

in Acoustics, Speech and Signal Processing (ICASSP), 2016 IEEE International Conference on (2016, May)

We consider the problem of sum-rate maximization in massive MIMO two-way relay networks with multiple (communication) operators employing the amplify-and-forward (AF) protocol. The aim is to design the ... [more ▼]

We consider the problem of sum-rate maximization in massive MIMO two-way relay networks with multiple (communication) operators employing the amplify-and-forward (AF) protocol. The aim is to design the relay amplification matrix (i.e., the relay beamformer) to maximize the achievable communication sum-rate through the relay. The design problem for the case of single-antenna users can be cast as a non-convex optimization problem, which in general, belongs to a class of NP-hard problems. We devise a method based on the minorization-maximization technique to obtain quality solutions to the problem. Each iteration of the proposed method consists of solving a strictly convex unconstrained quadratic program; this task can be done quite efficiently such that the suggested algorithm can handle the beamformer design for relays with up to ~ 70 antennas within a few minutes on an ordinary PC. Such a performance lays the ground for the proposed method to be employed in massive MIMO scenarios. [less ▲]

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See detailRate Splitting Multiple Access for Cognitive Radio GEO-LEO Co-Existing Satellite Networks
Khan, Wali Ullah UL; Ali, Zain; Lagunas, Eva et al

Scientific Conference (2022, December 07)

Low Earth orbit (LEO) satellite communication has drawn particular attention recently due to its high data rate services and low round-trip latency. It is low-cost to launch and can provide global ... [more ▼]

Low Earth orbit (LEO) satellite communication has drawn particular attention recently due to its high data rate services and low round-trip latency. It is low-cost to launch and can provide global coverage. However, the spectrum scarcity might be one of the critical challenges in the growth of LEO satellites, impacting severe restrictions on the development of ground-space integrated networks. To address this issue, we propose rate splitting multiple access (RSMA) for cognitive radio (CR) enabled nongeostationary orbit (GEO)-LEO coexisting satellite network. In particular, this work aims to maximize the system's sum rate by simultaneously optimizing the power allocation and subcarrier beam assignment of LEO satellite communication while restricting the interference temperature to GEO satellite users. The problem of sum rate maximization is formulated as non-convex and a Global optimal solution is challenging to obtain. Therefore, we first employ the successive convex approximation technique to reduce the complexity and make the problem more tractable. Then for the power allocation, we exploit Karush–Kuhn–Tucker (KKT) condition and adopt an efficient algorithm based on the greedy approach for subcarrier beam assignment. We also propose two suboptimal schemes with fixed power allocation and random subcarrier beam assignment. [less ▲]

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See detailRate Splitting Multiple Access for Next Generation Cognitive Radio Enabled LEO Satellite Networks
Khan, Wali Ullah UL; Ali, Zain; Lagunas, Eva UL et al

in Bulletin. Cornell University Libraries (2022)

Low Earth Orbit (LEO) satellite communication (SatCom) has drawn particular attention recently due to its high data rate services and low round-trip latency. It has low launching and manufacturing costs ... [more ▼]

Low Earth Orbit (LEO) satellite communication (SatCom) has drawn particular attention recently due to its high data rate services and low round-trip latency. It has low launching and manufacturing costs than Medium Earth Orbit (MEO) and Geostationary Earth Orbit (GEO) satellites. Moreover, LEO SatCom has the potential to provide global coverage with a high-speed data rate and low transmission latency. However, the spectrum scarcity might be one of the challenges in the growth of LEO satellites, impacting severe restrictions on developing ground-space integrated networks. To address this issue, cognitive radio and rate splitting multiple access (RSMA) are the two emerging technologies for high spectral efficiency and massive connectivity. This paper proposes a cognitive radio enabled LEO SatCom using RSMA radio access technique with the coexistence of GEO SatCom network. In particular, this work aims to maximize the sum rate of LEO SatCom by simultaneously optimizing the power budget over different beams, RSMA power allocation for users over each beam, and subcarrier user assignment while restricting the interference temperature to GEO SatCom. The problem of sum rate maximization is formulated as non-convex, where the global optimal solution is challenging to obtain. Thus, an efficient solution can be obtained in three steps: first we employ a successive convex approximation technique to reduce the complexity and make the problem more tractable. Second, for any given resource block user assignment, we adopt Karush–Kuhn–Tucker (KKT) conditions to calculate the transmit power over different beams and RSMA power allocation of users over each beam. Third, using the allocated power, we design an efficient algorithm based on the greedy approach for resource block user assignment. For comparison, we propose two suboptimal schemes with fixed power allocation over different beams and random resource block user assignment as the benchmark. Numerical results provided in this work are obtained based on the Monte Carlo simulations, which demonstrate the benefits of the proposed optimization scheme compared to the benchmark schemes. [less ▲]

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See detailRate-dependent phase-field damage modeling of rubber and its experimental parameter identification
Loew, Pascal Juergen UL; Peters, Bernhard UL; Beex, Lars UL

in Journal of the Mechanics and Physics of Solids (2019)

Phase-field models have the advantage in that no geometric descriptions of cracks are required, which means that crack coalescence and branching can be treated without additional effort. Miehe and ... [more ▼]

Phase-field models have the advantage in that no geometric descriptions of cracks are required, which means that crack coalescence and branching can be treated without additional effort. Miehe and Schänzel (2014) introduced a rate-independent phase-field damage model for finite strains in which a viscous damage regularization was proposed. We extend the model to depend on the loading rate and time by incorporating rubber’s strain-rate dependency in the constitutive description of the bulk, as well as in the damage driving force. The parameters of the model are identified using experiments at different strain rates. Local strain fields near the crack tip, obtained with digital image correlation (DIC), are used to help identify the length scale parameter. Three different degradation functions are assessed for their accuracy to model the rubber’s rate-dependent fracture. An adaptive time-stepping approach with a corrector scheme is furthermore employed to increase the computational efficiency with a factor of six, whereas an active set method guarantees the irreversibility of damage. Results detailing the energy storage and dissipation of the different model constituents are included, as well as validation results that show promising capabilities of rate-dependent phase-field modeling. [less ▲]

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See detailRates of convergence towards the Fréchet distribution
Bartholmé, Carine; Swan, Yvik UL

E-print/Working paper (2013)

We develop Stein's method for the Frechet distribution and apply it to compute rates of convergence in distribution of renormalized sample maxima to the Frechet distribution.

Detailed reference viewed: 306 (0 UL)