58 research outputs found

    Ultra wideband: applications, technology and future perspectives

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    Ultra Wide Band (UWB) wireless communications offers a radically different approach to wireless communication compared to conventional narrow band systems. Global interest in the technology is huge. This paper reports on the state of the art of UWB wireless technology and highlights key application areas, technological challenges, higher layer protocol issues, spectrum operating zones and future drivers. The majority of the discussion focuses on the state of the art of UWB technology as it is today and in the near future

    Data and the Digital Self: What the 21st Century Needs

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    Robert M. Ricketts and Rudolf Slavicek: dentistry by the rules of nature

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    The stomatognathic structures act as a complex and integrated system, thereby accomplishing several essential functions of the body. Aside from participating in food digestion, they are key for respiration and swallowing and play a central role in social interaction and stress management. The lifeworks of Robert M. Ricketts (1920–2003), an American orthodontist, and Rudolf Slavicek (1928–2022), an Austrian prosthodontist, were centered on this understanding. Both were educated in the time of gnathology, functional dentistry, and cephalometry and were ready to challenge conventional knowledge and traditions, leading toward innovation. As untiring clinicians, researchers, and mentors, they were fully invested in the study of the stomatognathic system, considering its morphology, dynamics, growth patterns, evolution, and interactions with the body and mind. Based on their extensive knowledge of the masticatory system, they advanced dentistry both with theoretical notions and by implementing new diagnostic and therapeutic concepts, thus reinforcing the idea of dentistry as a medical discipline requiring interdisciplinary effort. Their heritage is represented by numerous publications, discoveries, and inventions that inspire the dental community to follow their exemplary approach to the individualized care of patients. Their knowledge and passion are further passed on through their students. As part of their legacy, they prepared the ground for new research aimed at fostering advancements in occlusion medicine, hence supporting education in oral health

    OptimShare: A Unified Framework for Privacy Preserving Data Sharing -- Towards the Practical Utility of Data with Privacy

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    Tabular data sharing serves as a common method for data exchange. However, sharing sensitive information without adequate privacy protection can compromise individual privacy. Thus, ensuring privacy-preserving data sharing is crucial. Differential privacy (DP) is regarded as the gold standard in data privacy. Despite this, current DP methods tend to generate privacy-preserving tabular datasets that often suffer from limited practical utility due to heavy perturbation and disregard for the tables' utility dynamics. Besides, there has not been much research on selective attribute release, particularly in the context of controlled partially perturbed data sharing. This has significant implications for scenarios such as cross-agency data sharing in real-world situations. We introduce OptimShare: a utility-focused, multi-criteria solution designed to perturb input datasets selectively optimized for specific real-world applications. OptimShare combines the principles of differential privacy, fuzzy logic, and probability theory to establish an integrated tool for privacy-preserving data sharing. Empirical assessments confirm that OptimShare successfully strikes a balance between better data utility and robust privacy, effectively serving various real-world problem scenarios

    Selective Inhibitors of the JMJD2 Histone Demethylases: Combined Nondenaturing Mass Spectrometric Screening and Crystallographic Approaches†

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    Ferrous ion and 2-oxoglutarate (2OG) oxygenases catalyze the demethylation of N(epsilon)-methylated lysine residues in histones. Here we report studies on the inhibition of the JMJD2 subfamily of histone demethylases, employing binding analyses by nondenaturing mass spectrometry (MS), dynamic combinatorial chemistry coupled to MS, turnover assays, and crystallography. The results of initial binding and inhibition assays directed the production and analysis of a set of N-oxalyl-d-tyrosine derivatives to explore the extent of a subpocket at the JMJD2 active site. Some of the inhibitors were shown to be selective for JMJD2 over the hypoxia-inducible factor prolyl hydroxylase PHD2. A crystal structure of JMJD2A in complex with one of the potent inhibitors was obtained; modeling other inhibitors based on this structure predicts interactions that enable improved inhibition for some compounds

    Limits on the ultra-bright Fast Radio Burst population from the CHIME Pathfinder

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    We present results from a new incoherent-beam Fast Radio Burst (FRB) search on the Canadian Hydrogen Intensity Mapping Experiment (CHIME) Pathfinder. Its large instantaneous field of view (FoV) and relative thermal insensitivity allow us to probe the ultra-bright tail of the FRB distribution, and to test a recent claim that this distribution's slope, αlogNlogS\alpha\equiv-\frac{\partial \log N}{\partial \log S}, is quite small. A 256-input incoherent beamformer was deployed on the CHIME Pathfinder for this purpose. If the FRB distribution were described by a single power-law with α=0.7\alpha=0.7, we would expect an FRB detection every few days, making this the fastest survey on sky at present. We collected 1268 hours of data, amounting to one of the largest exposures of any FRB survey, with over 2.4\,×\times\,105^5\,deg2^2\,hrs. Having seen no bursts, we have constrained the rate of extremely bright events to < ⁣13<\!13\,sky1^{-1}\,day1^{-1} above \sim\,220(τ/ms)\sqrt{(\tau/\rm ms)} Jy\,ms for τ\tau between 1.3 and 100\,ms, at 400--800\,MHz. The non-detection also allows us to rule out α0.9\alpha\lesssim0.9 with 95%\% confidence, after marginalizing over uncertainties in the GBT rate at 700--900\,MHz, though we show that for a cosmological population and a large dynamic range in flux density, α\alpha is brightness-dependent. Since FRBs now extend to large enough distances that non-Euclidean effects are significant, there is still expected to be a dearth of faint events and relative excess of bright events. Nevertheless we have constrained the allowed number of ultra-intense FRBs. While this does not have significant implications for deeper, large-FoV surveys like full CHIME and APERTIF, it does have important consequences for other wide-field, small dish experiments

    Ribosomal oxygenases are structurally conserved from prokaryotes to humans

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    2-Oxoglutarate (2OG)-dependent oxygenases have important roles in the regulation of gene expression via demethylation of N-methylated chromatin components1,2 and in the hydroxylation of transcription factors3 and splicing factor proteins4. Recently, 2OG-dependent oxygenases that catalyse hydroxylation of transfer RNA5,6,7 and ribosomal proteins8 have been shown to be important in translation relating to cellular growth, TH17-cell differentiation and translational accuracy9,10,11,12. The finding that ribosomal oxygenases (ROXs) occur in organisms ranging from prokaryotes to humans8 raises questions as to their structural and evolutionary relationships. In Escherichia coli, YcfD catalyses arginine hydroxylation in the ribosomal protein L16; in humans, MYC-induced nuclear antigen (MINA53; also known as MINA) and nucleolar protein 66 (NO66) catalyse histidine hydroxylation in the ribosomal proteins RPL27A and RPL8, respectively. The functional assignments of ROXs open therapeutic possibilities via either ROX inhibition or targeting of differentially modified ribosomes. Despite differences in the residue and protein selectivities of prokaryotic and eukaryotic ROXs, comparison of the crystal structures of E. coli YcfD and Rhodothermus marinus YcfD with those of human MINA53 and NO66 reveals highly conserved folds and novel dimerization modes defining a new structural subfamily of 2OG-dependent oxygenases. ROX structures with and without their substrates support their functional assignments as hydroxylases but not demethylases, and reveal how the subfamily has evolved to catalyse the hydroxylation of different residue side chains of ribosomal proteins. Comparison of ROX crystal structures with those of other JmjC-domain-containing hydroxylases, including the hypoxia-inducible factor asparaginyl hydroxylase FIH and histone Nε-methyl lysine demethylases, identifies branch points in 2OG-dependent oxygenase evolution and distinguishes between JmjC-containing hydroxylases and demethylases catalysing modifications of translational and transcriptional machinery. The structures reveal that new protein hydroxylation activities can evolve by changing the coordination position from which the iron-bound substrate-oxidizing species reacts. This coordination flexibility has probably contributed to the evolution of the wide range of reactions catalysed by oxygenases

    Supplement: "Localization and broadband follow-up of the gravitational-wave transient GW150914" (2016, ApJL, 826, L13)

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    This Supplement provides supporting material for Abbott et al. (2016a). We briefly summarize past electromagnetic (EM) follow-up efforts as well as the organization and policy of the current EM follow-up program. We compare the four probability sky maps produced for the gravitational-wave transient GW150914, and provide additional details of the EM follow-up observations that were performed in the different bands
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