The Experts below are selected from a list of 795 Experts worldwide ranked by ideXlab platform
Bengt Norden - One of the best experts on this subject based on the ideXlab platform.
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kinetics for hybridization of peptide nucleic acids pna with dna and rna studied with the biacore technique
Biochemistry, 1997Co-Authors: Kristine Kilsa Jensen, Henrik Orum, Peter E Nielsen, Bengt NordenAbstract:The binding of a mixed-sequence pentadecamer PNA (peptide nucleic acid) containing all four nucleobases to the fully complementary as well as various singly mismatched RNA and DNA oligonucleotides has been systematically investigated using thermal denaturation and BIAcore surface-interaction techniques. The rate constants for association (k(a)) and dissociation (k(d)) of the duplex formation as well as the thermal stability (melting temperature, T-m) of the duplexes have been determined. Upon binding to PNA tethered via a biotin-linker to streptavidin at the dextran/gold surface, DNA and RNA sequences containing single mismatches at various positions in the center resulted in increased dissociation and decreased association rate constants. T-m values for PNA.RNA duplexes are on average 4 degrees C higher than for PNA.DNA duplexes and follow quantitatively the same variation with mismatches as do the PNA.RNA duplexes. Also a faster k(a) and a slower k(d) are found for PNA.RNA duplexes compared to the PNA.DNA duplexes. An overall fair correlation between T-m, k(a), and k(d) is found for a series of PNA.DNA and PNA.RNA duplexes although the determination of k(a) seemed to be prone to artifacts of the method and was not considered capable of providing absolute values representing the association rate constant in bulk solution.
John L. Haine - One of the best experts on this subject based on the ideXlab platform.
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a widely tunable full duplex transceiver combining electrical balance isolation and active analog cancellation
Vehicular Technology Conference, 2015Co-Authors: Leo Laughlin, Mark A Beach, Kevin A Morris, Chunqing Zhang, John L. HaineAbstract:Electrical balance Duplexers can provide high transmit-to-receive isolation whilst facilitating transmission and reception from a single antenna, can be implemented on-chip, and are widely tunable, making this an attractive technology for implementing full duplex architectures in small form factor devices. This paper presents measurements from a novel hardware prototype full- duplex transceiver architecture combining electrical balance and active analog cancellation. The prototype Duplexer achieves >80dB transmit-to- receive isolation over a 20MHz bandwidth at both 890MHz and 1890MHz, exceeding the performance of antenna separation architectures where the antenna isolation is limited to the levels achievable in hand held devices.
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Optimum single antenna full duplex using hybrid junctions
IEEE Journal on Selected Areas in Communications, 2014Co-Authors: Leo Laughlin, Mark A Beach, Kevin A Morris, John L. HaineAbstract:This paper investigates electrical balance (EB) in hybrid junctions as a method of achieving transmitter-receiver isolation in single antenna full duplex wireless systems. A novel technique for maximizing isolation in EB Duplexers is presented, and we show that the maximum achievable isolation is proportional to the variance of the antenna reflection coefficient with respect to frequency. Consequently, antenna characteristics can have a significant detrimental impact on the isolation bandwidth. Simulations that include embedded antenna measurements show a mean isolation of 62 dB over a 20-MHz bandwidth at 1.9 GHz but relatively poor performance at wider bandwidths. Furthermore, the operational environment can have a significant impact on isolation performance. We present a novel method of characterizing radio reflections being returned to a single antenna. Results show as little as 39 dB of attenuation in the radio echo for a highly reflective indoor environment at 1.9 GHz and that the mean isolation of an EB Duplexer is reduced by 7 dB in this environment. A full duplex architecture exploiting EB is proposed.
Kristine Kilsa Jensen - One of the best experts on this subject based on the ideXlab platform.
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kinetics for hybridization of peptide nucleic acids pna with dna and rna studied with the biacore technique
Biochemistry, 1997Co-Authors: Kristine Kilsa Jensen, Henrik Orum, Peter E Nielsen, Bengt NordenAbstract:The binding of a mixed-sequence pentadecamer PNA (peptide nucleic acid) containing all four nucleobases to the fully complementary as well as various singly mismatched RNA and DNA oligonucleotides has been systematically investigated using thermal denaturation and BIAcore surface-interaction techniques. The rate constants for association (k(a)) and dissociation (k(d)) of the duplex formation as well as the thermal stability (melting temperature, T-m) of the duplexes have been determined. Upon binding to PNA tethered via a biotin-linker to streptavidin at the dextran/gold surface, DNA and RNA sequences containing single mismatches at various positions in the center resulted in increased dissociation and decreased association rate constants. T-m values for PNA.RNA duplexes are on average 4 degrees C higher than for PNA.DNA duplexes and follow quantitatively the same variation with mismatches as do the PNA.RNA duplexes. Also a faster k(a) and a slower k(d) are found for PNA.RNA duplexes compared to the PNA.DNA duplexes. An overall fair correlation between T-m, k(a), and k(d) is found for a series of PNA.DNA and PNA.RNA duplexes although the determination of k(a) seemed to be prone to artifacts of the method and was not considered capable of providing absolute values representing the association rate constant in bulk solution.
Leo Laughlin - One of the best experts on this subject based on the ideXlab platform.
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a widely tunable full duplex transceiver combining electrical balance isolation and active analog cancellation
Vehicular Technology Conference, 2015Co-Authors: Leo Laughlin, Mark A Beach, Kevin A Morris, Chunqing Zhang, John L. HaineAbstract:Electrical balance Duplexers can provide high transmit-to-receive isolation whilst facilitating transmission and reception from a single antenna, can be implemented on-chip, and are widely tunable, making this an attractive technology for implementing full duplex architectures in small form factor devices. This paper presents measurements from a novel hardware prototype full- duplex transceiver architecture combining electrical balance and active analog cancellation. The prototype Duplexer achieves >80dB transmit-to- receive isolation over a 20MHz bandwidth at both 890MHz and 1890MHz, exceeding the performance of antenna separation architectures where the antenna isolation is limited to the levels achievable in hand held devices.
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electrical balance isolation for flexible duplexing in 5g mobile devices
International Conference on Communications, 2015Co-Authors: Leo Laughlin, Mark A Beach, Kevin A Morris, John HaineyAbstract:Exploiting new technologies will be vital in meeting the demanding requirements of 5G radio access. Flexible duplexing architectures will be a key enabling technology in 5G handsets, virtualising the radio spectrum, reducing cost, and increasing link capacity through full duplex radio communication. The tunability, low cost and small form factor of Electrical Balance (EB) duplexing technology makes it an attractive choice for flexible duplexing in small form factor devices. Circuit simulations incorporating measured antenna data have been used to investigate the performance of a dual notch EB Duplexer in a full duplex mode at 1900MHz. Results show that, in general, the isolation bandwidth of a dual notch EB Duplexer increases with the notch separation frequency, and that at bandwidths below 75MHz, dual notch balancing achieves transmit to receive isolation within 3dB of optimal balancing. The simulated Duplexer provides a 30dB isolation bandwidth of up to 200MHz. Therefore, in addition to providing tunable frequency division duplexing functionality, EB duplexing technology can also serve as a component of a broadband full duplex transceiver, thus providing a fully integrated flexible duplexing solution.
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Optimum single antenna full duplex using hybrid junctions
IEEE Journal on Selected Areas in Communications, 2014Co-Authors: Leo Laughlin, Mark A Beach, Kevin A Morris, John L. HaineAbstract:This paper investigates electrical balance (EB) in hybrid junctions as a method of achieving transmitter-receiver isolation in single antenna full duplex wireless systems. A novel technique for maximizing isolation in EB Duplexers is presented, and we show that the maximum achievable isolation is proportional to the variance of the antenna reflection coefficient with respect to frequency. Consequently, antenna characteristics can have a significant detrimental impact on the isolation bandwidth. Simulations that include embedded antenna measurements show a mean isolation of 62 dB over a 20-MHz bandwidth at 1.9 GHz but relatively poor performance at wider bandwidths. Furthermore, the operational environment can have a significant impact on isolation performance. We present a novel method of characterizing radio reflections being returned to a single antenna. Results show as little as 39 dB of attenuation in the radio echo for a highly reflective indoor environment at 1.9 GHz and that the mean isolation of an EB Duplexer is reduced by 7 dB in this environment. A full duplex architecture exploiting EB is proposed.
Charles A Haynes - One of the best experts on this subject based on the ideXlab platform.
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a new general model for predicting melting thermodynamics of complementary and mismatched b form duplexes containing locked nucleic acids application to probe design for digital pcr detection of somatic mutations
Biochemistry, 2015Co-Authors: Curtis Hughesman, Kareem Fakhfakh, Roza Bidshahri, Louise H Lund, Charles A HaynesAbstract:Advances in real-time polymerase chain reaction (PCR), as well as the emergence of digital PCR (dPCR) and useful modified nucleotide chemistries, including locked nucleic acids (LNAs), have created the potential to improve and expand clinical applications of PCR through their ability to better quantify and differentiate amplification products, but fully realizing this potential will require robust methods for designing dual-labeled hydrolysis probes and predicting their hybridization thermodynamics as a function of their sequence, chemistry, and template complementarity. We present here a nearest-neighbor thermodynamic model that accurately predicts the melting thermodynamics of a short oligonucleotide duplexed either to its perfect complement or to a template containing mismatched base pairs. The model may be applied to pure-DNA duplexes or to duplexes for which one strand contains any number and pattern of LNA substitutions. Perturbations to duplex stability arising from mismatched DNA:DNA or LNA:DNA ba...
