The Experts below are selected from a list of 84486 Experts worldwide ranked by ideXlab platform
Pratik Patil - One of the best experts on this subject based on the ideXlab platform.
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Hybrid data sharing and compression Strategy for downlink cloud radio access network
IEEE Transactions on Communications, 2018Co-Authors: Pratik Patil, Binbin DaiAbstract:This paper studies transmission strategies for the downlink of a cloud radio access network, in which the base stations are connected to a centralized cloud computing-based processor with digital fronthaul or backhaul links. We provide a system-level performance comparison of two fundamentally different strategies, namely, the data-sharing Strategy and the compression Strategy, which differ in the way the fronthaul/backhaul is utilized. It is observed that the performance of both strategies depends crucially on the available fronthaul or backhaul capacity. When the fronthaul/backhaul capacity is low, the data-sharing Strategy performs better, while under moderate-to-high fronthaul/backhaul capacity, the compression Strategy is superior. Using insights from such a comparison, we propose a novel Hybrid Strategy, combining the data-sharing and compression strategies, which allows for better control over the fronthaul/backhaul capacity utilization. An optimization framework for the Hybrid Strategy is proposed. Numerical evidence demonstrates the performance gain of the Hybrid Strategy.
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Hybrid compression and message-sharing Strategy for the downlink cloud radio-access network
2014 Information Theory and Applications Workshop ITA 2014 - Conference Proceedings, 2014Co-Authors: Pratik PatilAbstract:Cloud radio-access network (CRAN) is a wireless cellular network architecture in which the base-stations are connected to a cloud-computing based central processor with digital backhaul links. In this setting, the base-stations can be thought of as relays between the central processor and the user terminals. This paper considers the downlink of a cloud radio-access network with finite-capacity backhaul links. We model the overall network as a broadcast-relay channel, and propose a Hybrid compression and message-sharing Strategy for the downlink transmission. This paper further proposes numerical techniques for optimizing the quantization noise level in the compression part of the Hybrid precoding scheme. We compare the system-level performance of the proposed scheme with the pure compression and the pure message sharing schemes to show the benefit of the Hybrid Strategy for the downlink CRAN.
Binbin Dai - One of the best experts on this subject based on the ideXlab platform.
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Hybrid data sharing and compression Strategy for downlink cloud radio access network
IEEE Transactions on Communications, 2018Co-Authors: Pratik Patil, Binbin DaiAbstract:This paper studies transmission strategies for the downlink of a cloud radio access network, in which the base stations are connected to a centralized cloud computing-based processor with digital fronthaul or backhaul links. We provide a system-level performance comparison of two fundamentally different strategies, namely, the data-sharing Strategy and the compression Strategy, which differ in the way the fronthaul/backhaul is utilized. It is observed that the performance of both strategies depends crucially on the available fronthaul or backhaul capacity. When the fronthaul/backhaul capacity is low, the data-sharing Strategy performs better, while under moderate-to-high fronthaul/backhaul capacity, the compression Strategy is superior. Using insights from such a comparison, we propose a novel Hybrid Strategy, combining the data-sharing and compression strategies, which allows for better control over the fronthaul/backhaul capacity utilization. An optimization framework for the Hybrid Strategy is proposed. Numerical evidence demonstrates the performance gain of the Hybrid Strategy.
Albrecht Elsasser - One of the best experts on this subject based on the ideXlab platform.
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comparison of instantaneous wave free ratio ifr and fractional flow reserve ffr first real world experience
International Journal of Cardiology, 2015Co-Authors: Tobias Harle, Waldemar Bojara, Sven Meyer, Albrecht ElsasserAbstract:Abstract Background The instantaneous wave-free ratio (iFR) is a new adenosine-independent index of coronary stenosis severity. Most published data have been based on off-line analyses of pressure recordings in a core laboratory. We prospectively compared real-time iFR and fractional flow reserve (FFR) measurements. Methods and results iFR and FFR were measured in 151 coronary stenoses in 108 patients. Repeated iFR measurements were technically simple, showed excellent agreement [r s =0.99; p s =0.81; p Conclusions Real-time iFR measurements are easily performed, have excellent diagnostic performance and confirm available off-line core laboratory data. The excellent agreement between repeated iFR measurements demonstrates the reliability of single measurements. Combining iFR with FFR in a Hybrid Strategy enhances diagnostic accuracy, exposing fewer patients to adenosine. Overall, iFR is a promising method, but still requires prospective clinical endpoint trial evaluation.
Paul Rocchiccioli - One of the best experts on this subject based on the ideXlab platform.
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discordance between resting and hyperemic indices of coronary stenosis severity the verify 2 study a comparative study of resting coronary pressure gradient instantaneous wave free ratio and fractional flow reserve in an unselected population referred for invasive angiography
Circulation-cardiovascular Interventions, 2016Co-Authors: Barry Hennigan, Keith G Oldroyd, Colin Berry, Nils P Johnson, John D Mcclure, Peter Mccartney, Margaret Mcentegart, Hany Eteiba, Mark C Petrie, Paul RocchiccioliAbstract:Background— Distal coronary to aortic pressure ratio (Pd/Pa) and instantaneous wave-free ratio (iFR) are indices of functional significance of a coronary stenosis measured without hyperemia. It has been suggested that iFR has superior diagnostic accuracy to Pd/Pa when compared with fractional flow reserve (FFR). We hypothesized that in comparison with FFR, revascularization decisions based on either binary cutoff values for iFR and Pd/Pa or Hybrid strategies incorporating iFR or Pd/Pa will result in similar levels of disagreement. Methods and Results— This is a prospective study in consecutive patients undergoing FFR for clinical indications using proprietary software to calculate iFR. We measured Pd/Pa, iFR, FFR, and hyperemic iFR. Diagnostic accuracy versus FFR ≤0.80 was calculated using binary cutoff values of ≤0.90 for iFR and ≤0.92 for Pd/Pa, and adenosine zones for iFR of 0.86 to 0.93 and Pd/Pa of 0.87 to 0.94 in the Hybrid Strategy. One hundred ninety-seven patients with 257 stenoses (mean diameter stenosis 48%) were studied. Using binary cutoffs, diagnostic accuracy was similar for iFR and resting Pd/Pa with misclassification rates of 21% versus 20.2% ( P =0.85). In the Hybrid analysis, 54% of iFR cases and 53% of Pd/Pa cases were outside the adenosine zone and rates of misclassification were 9.4% versus 11.9% ( P =0.55). Conclusions— Binary cutoff values for iFR and Pd/Pa result in misclassification of 1 in 5 lesions. Using a Hybrid Strategy, approximately half of the patients do not receive adenosine, but 1 in 10 lesions are still misclassified. The use of nonhyperemic indices of stenosis severity cannot be recommended for decision making in the catheterization laboratory. Clinical Trial Registration— URL: . Unique identifier: [NCT02377310][1]. [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02377310&atom=%2Fcirccvint%2F9%2F11%2Fe004016.atom
Srinivasa-gopalan Sampathkumar - One of the best experts on this subject based on the ideXlab platform.
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carbohydrate neuroactive Hybrid Strategy for metabolic glycan engineering of the central nervous system in vivo
Journal of the American Chemical Society, 2017Co-Authors: Asif Shajahan, Shubham Parashar, Surbhi Goswami, Syed Meheboob Ahmed, Perumal Nagarajan, Srinivasa-gopalan SampathkumarAbstract:Sialic acids are abundant in the central nervous system (CNS) and are essential for brain development, learning, and memory. Dysregulation in biosynthesis of sialo-glycoconjugates is known to be associated with neurological disorders, CNS injury, and brain cancer. Metabolic glycan engineering (MGE) and bioorthogonal ligation have enabled study of biological roles of glycans in vivo; however, direct investigations of sialoglycans in brain have been intractable. We report a simple Strategy utilizing carbohydrate–neuroactive Hybrid (CNH) molecules, which exploit carrier-mediated transport systems available at the blood–brain barrier, to access brain via tail vein injection in mice. Peracetylated N-azidoacetyl-d-mannosamine (Ac4ManNAz) conjugated with neuroactive carriers, namely, nicotinic acid, valproic acid, theophylline-7-acetic acid, and choline, were synthesized and evaluated in SH-SY5Y (human neuroblastoma) cells for MGE. Intravenous administration of CNH molecules in mice (C57BL/6J and BALB/cByJ) resu...
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Carbohydrate–Neuroactive Hybrid Strategy for Metabolic Glycan Engineering of the Central Nervous System in Vivo
2016Co-Authors: Asif Shajahan, Shubham Parashar, Surbhi Goswami, Syed Meheboob Ahmed, Perumal Nagarajan, Srinivasa-gopalan SampathkumarAbstract:Sialic acids are abundant in the central nervous system (CNS) and are essential for brain development, learning, and memory. Dysregulation in biosynthesis of sialo-glycoconjugates is known to be associated with neurological disorders, CNS injury, and brain cancer. Metabolic glycan engineering (MGE) and bioorthogonal ligation have enabled study of biological roles of glycans in vivo; however, direct investigations of sialoglycans in brain have been intractable. We report a simple Strategy utilizing carbohydrate–neuroactive Hybrid (CNH) molecules, which exploit carrier-mediated transport systems available at the blood–brain barrier, to access brain via tail vein injection in mice. Peracetylated N-azidoacetyl-d-mannosamine (Ac4ManNAz) conjugated with neuroactive carriers, namely, nicotinic acid, valproic acid, theophylline-7-acetic acid, and choline, were synthesized and evaluated in SH-SY5Y (human neuroblastoma) cells for MGE. Intravenous administration of CNH molecules in mice (C57BL/6J and BALB/cByJ) resulted in robust expression of N-azidoacetyl-neuraminic acid (NeuAz)-carrying glycoproteins in both brain and heart, while the nonHybrid molecule Ac4ManNAz showed NeuAz expression in heart but not in brain. Successful neuroactive carriers were then conjugated with N-butanoyl-d-mannosamine (ManNBut) with a goal to achieve modulation of polysialic acid (polySia) on neural cell adhesion molecules (NCAM). PolySia levels on NCAM in adult mice were reduced significantly upon administration of Ac3ManNBut-nicotinate Hybrid, but not with Ac4ManNBut. This novel application of MGE not only offers a noninvasive tool for investigating brain glycosylation, which could be developed in to brain mapping applications, but also serves as a potential drug by which modulation of neural glycan biosynthesis and thus function can be achieved in vivo
