LDPC coded OFDM over the atmospheric turbulence channel.

PubMed

Djordjevic, Ivan B; Vasic, Bane; Neifeld, Mark A

2007-05-14

Low-density parity-check (LDPC) coded optical orthogonal frequency division multiplexing (OFDM) is shown to significantly outperform LDPC coded on-off keying (OOK) over the atmospheric turbulence channel in terms of both coding gain and spectral efficiency. In the regime of strong turbulence at a bit-error rate of 10(-5), the coding gain improvement of the LDPC coded single-side band unclipped-OFDM system with 64 sub-carriers is larger than the coding gain of the LDPC coded OOK system by 20.2 dB for quadrature-phase-shift keying (QPSK) and by 23.4 dB for binary-phase-shift keying (BPSK).

A novel QC-LDPC code based on the finite field multiplicative group for optical communications

NASA Astrophysics Data System (ADS)

Yuan, Jian-guo; Xu, Liang; Tong, Qing-zhen

2013-09-01

A novel construction method of quasi-cyclic low-density parity-check (QC-LDPC) code is proposed based on the finite field multiplicative group, which has easier construction, more flexible code-length code-rate adjustment and lower encoding/decoding complexity. Moreover, a regular QC-LDPC(5334,4962) code is constructed. The simulation results show that the constructed QC-LDPC(5334,4962) code can gain better error correction performance under the condition of the additive white Gaussian noise (AWGN) channel with iterative decoding sum-product algorithm (SPA). At the bit error rate (BER) of 10-6, the net coding gain (NCG) of the constructed QC-LDPC(5334,4962) code is 1.8 dB, 0.9 dB and 0.2 dB more than that of the classic RS(255,239) code in ITU-T G.975, the LDPC(32640,30592) code in ITU-T G.975.1 and the SCG-LDPC(3969,3720) code constructed by the random method, respectively. So it is more suitable for optical communication systems.

Polarization-multiplexed rate-adaptive non-binary-quasi-cyclic-LDPC-coded multilevel modulation with coherent detection for optical transport networks.

PubMed

Arabaci, Murat; Djordjevic, Ivan B; Saunders, Ross; Marcoccia, Roberto M

2010-02-01

In order to achieve high-speed transmission over optical transport networks (OTNs) and maximize its throughput, we propose using a rate-adaptive polarization-multiplexed coded multilevel modulation with coherent detection based on component non-binary quasi-cyclic (QC) LDPC codes. Compared to prior-art bit-interleaved LDPC-coded modulation (BI-LDPC-CM) scheme, the proposed non-binary LDPC-coded modulation (NB-LDPC-CM) scheme not only reduces latency due to symbol- instead of bit-level processing but also provides either impressive reduction in computational complexity or striking improvements in coding gain depending on the constellation size. As the paper presents, compared to its prior-art binary counterpart, the proposed NB-LDPC-CM scheme addresses the needs of future OTNs, which are achieving the target BER performance and providing maximum possible throughput both over the entire lifetime of the OTN, better.

RETRACTED — PMD mitigation through interleaving LDPC codes with polarization scramblers

NASA Astrophysics Data System (ADS)

Han, Dahai; Chen, Haoran; Xi, Lixia

2012-11-01

The combination of forward error correction (FEC) and distributed fast polarization scramblers (D-FPSs) is approved as an effective method to mitigate polarization mode dispersion (PMD) in high-speed optical fiber communication system. The low-density parity-check (LDPC) codes are newly introduced into the PMD mitigation scheme with D-FPSs in this paper as one of the promising FEC codes to achieve better performance. The scrambling speed of FPS for LDPC (2040, 1903) codes system is discussed, and the reasonable speed 10 MHz is obtained from the simulation results. For easy application in practical large scale integrated (LSI) circuit, the number of iterations in decoding LDPC codes is also investigated. The PMD tolerance and cut-off optical signal-to-noise ratio (OSNR) of LDPC codes are compared with Reed-Solomon (RS) codes in different conditions. In the simulation, the interleaving LDPC codes brings incremental performance of error correction, and the PMD tolerance is 10 ps at OSNR=11.4 dB. The results show that the meaning of the work is that LDPC codes are a substitute for traditional RS codes with D-FPSs and all of the executable code files are open for researchers who have practical LSI platform for PMD mitigation.

PMD mitigation through interleaving LDPC codes with polarization scramblers

NASA Astrophysics Data System (ADS)

Han, Dahai; Chen, Haoran; Xi, Lixia

2013-09-01

The combination of forward error correction (FEC) and distributed fast polarization scramblers (D-FPSs) is approved an effective method to mitigate polarization mode dispersion (PMD) in high-speed optical fiber communication system. The low-density parity-check (LDPC) codes are newly introduced into the PMD mitigation scheme with D-FPSs in this article as one of the promising FEC codes to achieve better performance. The scrambling speed of FPS for LDPC (2040, 1903) codes system is discussed, and the reasonable speed 10MHz is obtained from the simulation results. For easy application in practical large scale integrated (LSI) circuit, the number of iterations in decoding LDPC codes is also investigated. The PMD tolerance and cut-off optical signal-to-noise ratio (OSNR) of LDPC codes are compared with Reed-Solomon (RS) codes in different conditions. In the simulation, the interleaving LDPC codes bring incremental performance of error correction, and the PMD tolerance is 10ps at OSNR=11.4dB. The results show the meaning of the work is that LDPC codes are a substitute for traditional RS codes with D-FPSs and all of the executable code files are open for researchers who have practical LSI platform for PMD mitigation.

A novel construction method of QC-LDPC codes based on CRT for optical communications

NASA Astrophysics Data System (ADS)

Yuan, Jian-guo; Liang, Meng-qi; Wang, Yong; Lin, Jin-zhao; Pang, Yu

2016-05-01

A novel construction method of quasi-cyclic low-density parity-check (QC-LDPC) codes is proposed based on Chinese remainder theory (CRT). The method can not only increase the code length without reducing the girth, but also greatly enhance the code rate, so it is easy to construct a high-rate code. The simulation results show that at the bit error rate ( BER) of 10-7, the net coding gain ( NCG) of the regular QC-LDPC(4 851, 4 546) code is respectively 2.06 dB, 1.36 dB, 0.53 dB and 0.31 dB more than those of the classic RS(255, 239) code in ITU-T G.975, the LDPC(32 640, 30 592) code in ITU-T G.975.1, the QC-LDPC(3 664, 3 436) code constructed by the improved combining construction method based on CRT and the irregular QC-LDPC(3 843, 3 603) code constructed by the construction method based on the Galois field ( GF( q)) multiplicative group. Furthermore, all these five codes have the same code rate of 0.937. Therefore, the regular QC-LDPC(4 851, 4 546) code constructed by the proposed construction method has excellent error-correction performance, and can be more suitable for optical transmission systems.

Construction of a new regular LDPC code for optical transmission systems

NASA Astrophysics Data System (ADS)

Yuan, Jian-guo; Tong, Qing-zhen; Xu, Liang; Huang, Sheng

2013-05-01

A novel construction method of the check matrix for the regular low density parity check (LDPC) code is proposed. The novel regular systematically constructed Gallager (SCG)-LDPC(3969,3720) code with the code rate of 93.7% and the redundancy of 6.69% is constructed. The simulation results show that the net coding gain (NCG) and the distance from the Shannon limit of the novel SCG-LDPC(3969,3720) code can respectively be improved by about 1.93 dB and 0.98 dB at the bit error rate (BER) of 10-8, compared with those of the classic RS(255,239) code in ITU-T G.975 recommendation and the LDPC(32640,30592) code in ITU-T G.975.1 recommendation with the same code rate of 93.7% and the same redundancy of 6.69%. Therefore, the proposed novel regular SCG-LDPC(3969,3720) code has excellent performance, and is more suitable for high-speed long-haul optical transmission systems.

Construction method of QC-LDPC codes based on multiplicative group of finite field in optical communication

NASA Astrophysics Data System (ADS)

Huang, Sheng; Ao, Xiang; Li, Yuan-yuan; Zhang, Rui

2016-09-01

In order to meet the needs of high-speed development of optical communication system, a construction method of quasi-cyclic low-density parity-check (QC-LDPC) codes based on multiplicative group of finite field is proposed. The Tanner graph of parity check matrix of the code constructed by this method has no cycle of length 4, and it can make sure that the obtained code can get a good distance property. Simulation results show that when the bit error rate ( BER) is 10-6, in the same simulation environment, the net coding gain ( NCG) of the proposed QC-LDPC(3 780, 3 540) code with the code rate of 93.7% in this paper is improved by 2.18 dB and 1.6 dB respectively compared with those of the RS(255, 239) code in ITU-T G.975 and the LDPC(3 2640, 3 0592) code in ITU-T G.975.1. In addition, the NCG of the proposed QC-LDPC(3 780, 3 540) code is respectively 0.2 dB and 0.4 dB higher compared with those of the SG-QC-LDPC(3 780, 3 540) code based on the two different subgroups in finite field and the AS-QC-LDPC(3 780, 3 540) code based on the two arbitrary sets of a finite field. Thus, the proposed QC-LDPC(3 780, 3 540) code in this paper can be well applied in optical communication systems.

Fast QC-LDPC code for free space optical communication

NASA Astrophysics Data System (ADS)

Wang, Jin; Zhang, Qi; Udeh, Chinonso Paschal; Wu, Rangzhong

2017-02-01

Free Space Optical (FSO) Communication systems use the atmosphere as a propagation medium. Hence the atmospheric turbulence effects lead to multiplicative noise related with signal intensity. In order to suppress the signal fading induced by multiplicative noise, we propose a fast Quasi-Cyclic (QC) Low-Density Parity-Check (LDPC) code for FSO Communication systems. As a linear block code based on sparse matrix, the performances of QC-LDPC is extremely near to the Shannon limit. Currently, the studies on LDPC code in FSO Communications is mainly focused on Gauss-channel and Rayleigh-channel, respectively. In this study, the LDPC code design over atmospheric turbulence channel which is nether Gauss-channel nor Rayleigh-channel is closer to the practical situation. Based on the characteristics of atmospheric channel, which is modeled as logarithmic-normal distribution and K-distribution, we designed a special QC-LDPC code, and deduced the log-likelihood ratio (LLR). An irregular QC-LDPC code for fast coding, of which the rates are variable, is proposed in this paper. The proposed code achieves excellent performance of LDPC codes and can present the characteristics of high efficiency in low rate, stable in high rate and less number of iteration. The result of belief propagation (BP) decoding shows that the bit error rate (BER) obviously reduced as the Signal-to-Noise Ratio (SNR) increased. Therefore, the LDPC channel coding technology can effectively improve the performance of FSO. At the same time, the BER, after decoding reduces with the increase of SNR arbitrarily, and not having error limitation platform phenomenon with error rate slowing down.

LDPC-coded orbital angular momentum (OAM) modulation for free-space optical communication.

PubMed

Djordjevic, Ivan B; Arabaci, Murat

2010-11-22

An orbital angular momentum (OAM) based LDPC-coded modulation scheme suitable for use in FSO communication is proposed. We demonstrate that the proposed scheme can operate under strong atmospheric turbulence regime and enable 100 Gb/s optical transmission while employing 10 Gb/s components. Both binary and nonbinary LDPC-coded OAM modulations are studied. In addition to providing better BER performance, the nonbinary LDPC-coded modulation reduces overall decoder complexity and latency. The nonbinary LDPC-coded OAM modulation provides a net coding gain of 9.3 dB at the BER of 10(-8). The maximum-ratio combining scheme outperforms the corresponding equal-gain combining scheme by almost 2.5 dB.

Discussion on LDPC Codes and Uplink Coding

NASA Technical Reports Server (NTRS)

Andrews, Ken; Divsalar, Dariush; Dolinar, Sam; Moision, Bruce; Hamkins, Jon; Pollara, Fabrizio

2007-01-01

This slide presentation reviews the progress that the workgroup on Low-Density Parity-Check (LDPC) for space link coding. The workgroup is tasked with developing and recommending new error correcting codes for near-Earth, Lunar, and deep space applications. Included in the presentation is a summary of the technical progress of the workgroup. Charts that show the LDPC decoder sensitivity to symbol scaling errors are reviewed, as well as a chart showing the performance of several frame synchronizer algorithms compared to that of some good codes and LDPC decoder tests at ESTL. Also reviewed is a study on Coding, Modulation, and Link Protocol (CMLP), and the recommended codes. A design for the Pseudo-Randomizer with LDPC Decoder and CRC is also reviewed. A chart that summarizes the three proposed coding systems is also presented.

Accumulate-Repeat-Accumulate-Accumulate-Codes

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Dolinar, Sam; Thorpe, Jeremy

2004-01-01

Inspired by recently proposed Accumulate-Repeat-Accumulate (ARA) codes [15], in this paper we propose a channel coding scheme called Accumulate-Repeat-Accumulate-Accumulate (ARAA) codes. These codes can be seen as serial turbo-like codes or as a subclass of Low Density Parity Check (LDPC) codes, and they have a projected graph or protograph representation; this allows for a high-speed iterative decoder implementation using belief propagation. An ARAA code can be viewed as a precoded Repeat-and-Accumulate (RA) code with puncturing in concatenation with another accumulator, where simply an accumulator is chosen as the precoder; thus ARAA codes have a very fast encoder structure. Using density evolution on their associated protographs, we find examples of rate-lJ2 ARAA codes with maximum variable node degree 4 for which a minimum bit-SNR as low as 0.21 dB from the channel capacity limit can be achieved as the block size goes to infinity. Such a low threshold cannot be achieved by RA or Irregular RA (IRA) or unstructured irregular LDPC codes with the same constraint on the maximum variable node degree. Furthermore by puncturing the accumulators we can construct families of higher rate ARAA codes with thresholds that stay close to their respective channel capacity thresholds uniformly. Iterative decoding simulation results show comparable performance with the best-known LDPC codes but with very low error floor even at moderate block sizes.

A rate-compatible family of protograph-based LDPC codes built by expurgation and lengthening

NASA Technical Reports Server (NTRS)

Dolinar, Sam

2005-01-01

We construct a protograph-based rate-compatible family of low-density parity-check codes that cover a very wide range of rates from 1/2 to 16/17, perform within about 0.5 dB of their capacity limits for all rates, and can be decoded conveniently and efficiently with a common hardware implementation.

Low Density Parity Check Codes Based on Finite Geometries: A Rediscovery and More

NASA Technical Reports Server (NTRS)

Kou, Yu; Lin, Shu; Fossorier, Marc

1999-01-01

Low density parity check (LDPC) codes with iterative decoding based on belief propagation achieve astonishing error performance close to Shannon limit. No algebraic or geometric method for constructing these codes has been reported and they are largely generated by computer search. As a result, encoding of long LDPC codes is in general very complex. This paper presents two classes of high rate LDPC codes whose constructions are based on finite Euclidean and projective geometries, respectively. These classes of codes a.re cyclic and have good constraint parameters and minimum distances. Cyclic structure adows the use of linear feedback shift registers for encoding. These finite geometry LDPC codes achieve very good error performance with either soft-decision iterative decoding based on belief propagation or Gallager's hard-decision bit flipping algorithm. These codes can be punctured or extended to obtain other good LDPC codes. A generalization of these codes is also presented.

FPGA implementation of concatenated non-binary QC-LDPC codes for high-speed optical transport.

PubMed

Zou, Ding; Djordjevic, Ivan B

2015-06-01

In this paper, we propose a soft-decision-based FEC scheme that is the concatenation of a non-binary LDPC code and hard-decision FEC code. The proposed NB-LDPC + RS with overhead of 27.06% provides a superior NCG of 11.9dB at a post-FEC BER of 10^-15. As a result, the proposed NB-LDPC codes represent the strong FEC candidate of soft-decision FEC for beyond 100Gb/s optical transmission systems.

FPGA implementation of high-performance QC-LDPC decoder for optical communications

NASA Astrophysics Data System (ADS)

Zou, Ding; Djordjevic, Ivan B.

2015-01-01

Forward error correction is as one of the key technologies enabling the next-generation high-speed fiber optical communications. Quasi-cyclic (QC) low-density parity-check (LDPC) codes have been considered as one of the promising candidates due to their large coding gain performance and low implementation complexity. In this paper, we present our designed QC-LDPC code with girth 10 and 25% overhead based on pairwise balanced design. By FPGAbased emulation, we demonstrate that the 5-bit soft-decision LDPC decoder can achieve 11.8dB net coding gain with no error floor at BER of 10-15 avoiding using any outer code or post-processing method. We believe that the proposed single QC-LDPC code is a promising solution for 400Gb/s optical communication systems and beyond.

A novel construction method of QC-LDPC codes based on the subgroup of the finite field multiplicative group for optical transmission systems

NASA Astrophysics Data System (ADS)

Yuan, Jian-guo; Zhou, Guang-xiang; Gao, Wen-chun; Wang, Yong; Lin, Jin-zhao; Pang, Yu

2016-01-01

According to the requirements of the increasing development for optical transmission systems, a novel construction method of quasi-cyclic low-density parity-check (QC-LDPC) codes based on the subgroup of the finite field multiplicative group is proposed. Furthermore, this construction method can effectively avoid the girth-4 phenomena and has the advantages such as simpler construction, easier implementation, lower encoding/decoding complexity, better girth properties and more flexible adjustment for the code length and code rate. The simulation results show that the error correction performance of the QC-LDPC(3 780,3 540) code with the code rate of 93.7% constructed by this proposed method is excellent, its net coding gain is respectively 0.3 dB, 0.55 dB, 1.4 dB and 1.98 dB higher than those of the QC-LDPC(5 334,4 962) code constructed by the method based on the inverse element characteristics in the finite field multiplicative group, the SCG-LDPC(3 969,3 720) code constructed by the systematically constructed Gallager (SCG) random construction method, the LDPC(32 640,30 592) code in ITU-T G.975.1 and the classic RS(255,239) code which is widely used in optical transmission systems in ITU-T G.975 at the bit error rate ( BER) of 10-7. Therefore, the constructed QC-LDPC(3 780,3 540) code is more suitable for optical transmission systems.

Efficient Signal, Code, and Receiver Designs for MIMO Communication Systems

DTIC Science & Technology

2003-06-01

167 5-31 Concatenation of a tilted-QAM inner code with an LDPC outer code with a two component iterative soft-decision decoder. . . . . . . . . 168 5...for AWGN channels has long been studied. There are well-known soft-decision codes like the turbo codes and LDPC codes that can approach capacity to...bits) low density parity check ( LDPC ) code 1. 2. The coded bits are randomly interleaved so that bits nearby go through different sub-channels, and are

Optical LDPC decoders for beyond 100 Gbits/s optical transmission.

PubMed

Djordjevic, Ivan B; Xu, Lei; Wang, Ting

2009-05-01

We present an optical low-density parity-check (LDPC) decoder suitable for implementation above 100 Gbits/s, which provides large coding gains when based on large-girth LDPC codes. We show that a basic building block, the probabilities multiplier circuit, can be implemented using a Mach-Zehnder interferometer, and we propose corresponding probabilistic-domain sum-product algorithm (SPA). We perform simulations of a fully parallel implementation employing girth-10 LDPC codes and proposed SPA. The girth-10 LDPC(24015,19212) code of the rate of 0.8 outperforms the BCH(128,113)xBCH(256,239) turbo-product code of the rate of 0.82 by 0.91 dB (for binary phase-shift keying at 100 Gbits/s and a bit error rate of 10(-9)), and provides a net effective coding gain of 10.09 dB.

Experimental research and comparison of LDPC and RS channel coding in ultraviolet communication systems.

PubMed

Wu, Menglong; Han, Dahai; Zhang, Xiang; Zhang, Feng; Zhang, Min; Yue, Guangxin

2014-03-10

We have implemented a modified Low-Density Parity-Check (LDPC) codec algorithm in ultraviolet (UV) communication system. Simulations are conducted with measured parameters to evaluate the LDPC-based UV system performance. Moreover, LDPC (960, 480) and RS (18, 10) are implemented and experimented via a non-line-of-sight (NLOS) UV test bed. The experimental results are in agreement with the simulation and suggest that based on the given power and 10(-3)bit error rate (BER), in comparison with an uncoded system, average communication distance increases 32% with RS code, while 78% with LDPC code.

Throughput Optimization Via Adaptive MIMO Communications

DTIC Science & Technology

2006-05-30

End-to-end matlab packet simulation platform. * Low density parity check code (LDPCC). * Field trials with Silvus DSP MIMO testbed. * High mobility...incorporate advanced LDPC (low density parity check) codes . Realizing that the power of LDPC codes come at the price of decoder complexity, we also...Channel Coding Binary Convolution Code or LDPC Packet Length 0 - 216-1, bytes Coding Rate 1/2, 2/3, 3/4, 5/6 MIMO Channel Training Length 0 - 4, symbols

Percolation bounds for decoding thresholds with correlated erasures in quantum LDPC codes

NASA Astrophysics Data System (ADS)

Hamilton, Kathleen; Pryadko, Leonid

Correlations between errors can dramatically affect decoding thresholds, in some cases eliminating the threshold altogether. We analyze the existence of a threshold for quantum low-density parity-check (LDPC) codes in the case of correlated erasures. When erasures are positively correlated, the corresponding multi-variate Bernoulli distribution can be modeled in terms of cluster errors, where qubits in clusters of various size can be marked all at once. In a code family with distance scaling as a power law of the code length, erasures can be always corrected below percolation on a qubit adjacency graph associated with the code. We bound this correlated percolation transition by weighted (uncorrelated) percolation on a specially constructed cluster connectivity graph, and apply our recent results to construct several bounds for the latter. This research was supported in part by the NSF Grant PHY-1416578 and by the ARO Grant W911NF-14-1-0272.

A Golay complementary TS-based symbol synchronization scheme in variable rate LDPC-coded MB-OFDM UWBoF system

NASA Astrophysics Data System (ADS)

He, Jing; Wen, Xuejie; Chen, Ming; Chen, Lin

2015-09-01

In this paper, a Golay complementary training sequence (TS)-based symbol synchronization scheme is proposed and experimentally demonstrated in multiband orthogonal frequency division multiplexing (MB-OFDM) ultra-wideband over fiber (UWBoF) system with a variable rate low-density parity-check (LDPC) code. Meanwhile, the coding gain and spectral efficiency in the variable rate LDPC-coded MB-OFDM UWBoF system are investigated. By utilizing the non-periodic auto-correlation property of the Golay complementary pair, the start point of LDPC-coded MB-OFDM UWB signal can be estimated accurately. After 100 km standard single-mode fiber (SSMF) transmission, at the bit error rate of 1×10-3, the experimental results show that the short block length 64QAM-LDPC coding provides a coding gain of 4.5 dB, 3.8 dB and 2.9 dB for a code rate of 62.5%, 75% and 87.5%, respectively.

Cooperative MIMO communication at wireless sensor network: an error correcting code approach.

PubMed

Islam, Mohammad Rakibul; Han, Young Shin

2011-01-01

Cooperative communication in wireless sensor network (WSN) explores the energy efficient wireless communication schemes between multiple sensors and data gathering node (DGN) by exploiting multiple input multiple output (MIMO) and multiple input single output (MISO) configurations. In this paper, an energy efficient cooperative MIMO (C-MIMO) technique is proposed where low density parity check (LDPC) code is used as an error correcting code. The rate of LDPC code is varied by varying the length of message and parity bits. Simulation results show that the cooperative communication scheme outperforms SISO scheme in the presence of LDPC code. LDPC codes with different code rates are compared using bit error rate (BER) analysis. BER is also analyzed under different Nakagami fading scenario. Energy efficiencies are compared for different targeted probability of bit error p(b). It is observed that C-MIMO performs more efficiently when the targeted p(b) is smaller. Also the lower encoding rate for LDPC code offers better error characteristics.

Cooperative MIMO Communication at Wireless Sensor Network: An Error Correcting Code Approach

PubMed Central

Islam, Mohammad Rakibul; Han, Young Shin

2011-01-01

Cooperative communication in wireless sensor network (WSN) explores the energy efficient wireless communication schemes between multiple sensors and data gathering node (DGN) by exploiting multiple input multiple output (MIMO) and multiple input single output (MISO) configurations. In this paper, an energy efficient cooperative MIMO (C-MIMO) technique is proposed where low density parity check (LDPC) code is used as an error correcting code. The rate of LDPC code is varied by varying the length of message and parity bits. Simulation results show that the cooperative communication scheme outperforms SISO scheme in the presence of LDPC code. LDPC codes with different code rates are compared using bit error rate (BER) analysis. BER is also analyzed under different Nakagami fading scenario. Energy efficiencies are compared for different targeted probability of bit error pb. It is observed that C-MIMO performs more efficiently when the targeted pb is smaller. Also the lower encoding rate for LDPC code offers better error characteristics. PMID:22163732

High-throughput GPU-based LDPC decoding

NASA Astrophysics Data System (ADS)

Chang, Yang-Lang; Chang, Cheng-Chun; Huang, Min-Yu; Huang, Bormin

2010-08-01

Low-density parity-check (LDPC) code is a linear block code known to approach the Shannon limit via the iterative sum-product algorithm. LDPC codes have been adopted in most current communication systems such as DVB-S2, WiMAX, WI-FI and 10GBASE-T. LDPC for the needs of reliable and flexible communication links for a wide variety of communication standards and configurations have inspired the demand for high-performance and flexibility computing. Accordingly, finding a fast and reconfigurable developing platform for designing the high-throughput LDPC decoder has become important especially for rapidly changing communication standards and configurations. In this paper, a new graphic-processing-unit (GPU) LDPC decoding platform with the asynchronous data transfer is proposed to realize this practical implementation. Experimental results showed that the proposed GPU-based decoder achieved 271x speedup compared to its CPU-based counterpart. It can serve as a high-throughput LDPC decoder.

Low-Density Parity-Check (LDPC) Codes Constructed from Protographs

NASA Astrophysics Data System (ADS)

Thorpe, J.

2003-08-01

We introduce a new class of low-density parity-check (LDPC) codes constructed from a template called a protograph. The protograph serves as a blueprint for constructing LDPC codes of arbitrary size whose performance can be predicted by analyzing the protograph. We apply standard density evolution techniques to predict the performance of large protograph codes. Finally, we use a randomized search algorithm to find good protographs.

A Simulation Testbed for Adaptive Modulation and Coding in Airborne Telemetry

DTIC Science & Technology

2014-05-29

its modulation waveforms and LDPC for the FEC codes . It also uses several sets of published telemetry channel sounding data as its channel models...waveforms and LDPC for the FEC codes . It also uses several sets of published telemetry channel sounding data as its channel models. Within the context...check ( LDPC ) codes with tunable code rates, and both static and dynamic telemetry channel models are included. In an effort to maximize the

Spatially coupled low-density parity-check error correction for holographic data storage

NASA Astrophysics Data System (ADS)

Ishii, Norihiko; Katano, Yutaro; Muroi, Tetsuhiko; Kinoshita, Nobuhiro

2017-09-01

The spatially coupled low-density parity-check (SC-LDPC) was considered for holographic data storage. The superiority of SC-LDPC was studied by simulation. The simulations show that the performance of SC-LDPC depends on the lifting number, and when the lifting number is over 100, SC-LDPC shows better error correctability compared with irregular LDPC. SC-LDPC is applied to the 5:9 modulation code, which is one of the differential codes. The error-free point is near 2.8 dB and over 10-1 can be corrected in simulation. From these simulation results, this error correction code can be applied to actual holographic data storage test equipment. Results showed that 8 × 10-2 can be corrected, furthermore it works effectively and shows good error correctability.

Parallel Subspace Subcodes of Reed-Solomon Codes for Magnetic Recording Channels

ERIC Educational Resources Information Center

Wang, Han

2010-01-01

Read channel architectures based on a single low-density parity-check (LDPC) code are being considered for the next generation of hard disk drives. However, LDPC-only solutions suffer from the error floor problem, which may compromise reliability, if not handled properly. Concatenated architectures using an LDPC code plus a Reed-Solomon (RS) code…

Protograph LDPC Codes for the Erasure Channel

NASA Technical Reports Server (NTRS)

Pollara, Fabrizio; Dolinar, Samuel J.; Divsalar, Dariush

2006-01-01

This viewgraph presentation reviews the use of protograph Low Density Parity Check (LDPC) codes for erasure channels. A protograph is a Tanner graph with a relatively small number of nodes. A "copy-and-permute" operation can be applied to the protograph to obtain larger derived graphs of various sizes. For very high code rates and short block sizes, a low asymptotic threshold criterion is not the best approach to designing LDPC codes. Simple protographs with much regularity and low maximum node degrees appear to be the best choices Quantized-rateless protograph LDPC codes can be built by careful design of the protograph such that multiple puncturing patterns will still permit message passing decoding to proceed

Experimental study of non-binary LDPC coding for long-haul coherent optical QPSK transmissions.

PubMed

Zhang, Shaoliang; Arabaci, Murat; Yaman, Fatih; Djordjevic, Ivan B; Xu, Lei; Wang, Ting; Inada, Yoshihisa; Ogata, Takaaki; Aoki, Yasuhiro

2011-09-26

The performance of rate-0.8 4-ary LDPC code has been studied in a 50 GHz-spaced 40 Gb/s DWDM system with PDM-QPSK modulation. The net effective coding gain of 10 dB is obtained at BER of 10(-6). With the aid of time-interleaving polarization multiplexing and MAP detection, 10,560 km transmission over legacy dispersion managed fiber is achieved without any countable errors. The proposed nonbinary quasi-cyclic LDPC code achieves an uncoded BER threshold at 4×10(-2). Potential issues like phase ambiguity and coding length are also discussed when implementing LDPC in current coherent optical systems. © 2011 Optical Society of America

Evaluation of large girth LDPC codes for PMD compensation by turbo equalization.

PubMed

Minkov, Lyubomir L; Djordjevic, Ivan B; Xu, Lei; Wang, Ting; Kueppers, Franko

2008-08-18

Large-girth quasi-cyclic LDPC codes have been experimentally evaluated for use in PMD compensation by turbo equalization for a 10 Gb/s NRZ optical transmission system, and observing one sample per bit. Net effective coding gain improvement for girth-10, rate 0.906 code of length 11936 over maximum a posteriori probability (MAP) detector for differential group delay of 125 ps is 6.25 dB at BER of 10(-6). Girth-10 LDPC code of rate 0.8 outperforms the girth-10 code of rate 0.906 by 2.75 dB, and provides the net effective coding gain improvement of 9 dB at the same BER. It is experimentally determined that girth-10 LDPC codes of length around 15000 approach channel capacity limit within 1.25 dB.

Advanced GF(3²) nonbinary LDPC coded modulation with non-uniform 9-QAM outperforming star 8-QAM.

PubMed

Liu, Tao; Lin, Changyu; Djordjevic, Ivan B

2016-06-27

In this paper, we first describe a 9-symbol non-uniform signaling scheme based on Huffman code, in which different symbols are transmitted with different probabilities. By using the Huffman procedure, prefix code is designed to approach the optimal performance. Then, we introduce an algorithm to determine the optimal signal constellation sets for our proposed non-uniform scheme with the criterion of maximizing constellation figure of merit (CFM). The proposed nonuniform polarization multiplexed signaling 9-QAM scheme has the same spectral efficiency as the conventional 8-QAM. Additionally, we propose a specially designed GF(3²) nonbinary quasi-cyclic LDPC code for the coded modulation system based on the 9-QAM non-uniform scheme. Further, we study the efficiency of our proposed non-uniform 9-QAM, combined with nonbinary LDPC coding, and demonstrate by Monte Carlo simulation that the proposed GF(2³) nonbinary LDPC coded 9-QAM scheme outperforms nonbinary LDPC coded uniform 8-QAM by at least 0.8dB.

Coded Cooperation for Multiway Relaying in Wireless Sensor Networks †

PubMed Central

Si, Zhongwei; Ma, Junyang; Thobaben, Ragnar

2015-01-01

Wireless sensor networks have been considered as an enabling technology for constructing smart cities. One important feature of wireless sensor networks is that the sensor nodes collaborate in some manner for communications. In this manuscript, we focus on the model of multiway relaying with full data exchange where each user wants to transmit and receive data to and from all other users in the network. We derive the capacity region for this specific model and propose a coding strategy through coset encoding. To obtain good performance with practical codes, we choose spatially-coupled LDPC (SC-LDPC) codes for the coded cooperation. In particular, for the message broadcasting from the relay, we construct multi-edge-type (MET) SC-LDPC codes by repeatedly applying coset encoding. Due to the capacity-achieving property of the SC-LDPC codes, we prove that the capacity region can theoretically be achieved by the proposed MET SC-LDPC codes. Numerical results with finite node degrees are provided, which show that the achievable rates approach the boundary of the capacity region in both binary erasure channels and additive white Gaussian channels. PMID:26131675

Coded Cooperation for Multiway Relaying in Wireless Sensor Networks.

PubMed

Si, Zhongwei; Ma, Junyang; Thobaben, Ragnar

2015-06-29

Wireless sensor networks have been considered as an enabling technology for constructing smart cities. One important feature of wireless sensor networks is that the sensor nodes collaborate in some manner for communications. In this manuscript, we focus on the model of multiway relaying with full data exchange where each user wants to transmit and receive data to and from all other users in the network. We derive the capacity region for this specific model and propose a coding strategy through coset encoding. To obtain good performance with practical codes, we choose spatially-coupled LDPC (SC-LDPC) codes for the coded cooperation. In particular, for the message broadcasting from the relay, we construct multi-edge-type (MET) SC-LDPC codes by repeatedly applying coset encoding. Due to the capacity-achieving property of the SC-LDPC codes, we prove that the capacity region can theoretically be achieved by the proposed MET SC-LDPC codes. Numerical results with finite node degrees are provided, which show that the achievable rates approach the boundary of the capacity region in both binary erasure channels and additive white Gaussian channels.

Ultra high speed optical transmission using subcarrier-multiplexed four-dimensional LDPC-coded modulation.

PubMed

Batshon, Hussam G; Djordjevic, Ivan; Schmidt, Ted

2010-09-13

We propose a subcarrier-multiplexed four-dimensional LDPC bit-interleaved coded modulation scheme that is capable of achieving beyond 480 Gb/s single-channel transmission rate over optical channels. Subcarrier-multiplexed four-dimensional LDPC coded modulation scheme outperforms the corresponding dual polarization schemes by up to 4.6 dB in OSNR at BER 10(-8).

Self-Configuration and Localization in Ad Hoc Wireless Sensor Networks

DTIC Science & Technology

2010-08-31

Goddard I. SUMMARY OF CONTRIBUTIONS We explored the error mechanisms of iterative decoding of low-density parity-check ( LDPC ) codes . This work has resulted...important problems in the area of channel coding , as their unpredictable behavior has impeded the deployment of LDPC codes in many real-world applications. We...tree-based decoders of LDPC codes , including the extrinsic tree decoder, and an investigation into their performance and bounding capabilities [5], [6

Scalable video transmission over Rayleigh fading channels using LDPC codes

NASA Astrophysics Data System (ADS)

Bansal, Manu; Kondi, Lisimachos P.

2005-03-01

In this paper, we investigate an important problem of efficiently utilizing the available resources for video transmission over wireless channels while maintaining a good decoded video quality and resilience to channel impairments. Our system consists of the video codec based on 3-D set partitioning in hierarchical trees (3-D SPIHT) algorithm and employs two different schemes using low-density parity check (LDPC) codes for channel error protection. The first method uses the serial concatenation of the constant-rate LDPC code and rate-compatible punctured convolutional (RCPC) codes. Cyclic redundancy check (CRC) is used to detect transmission errors. In the other scheme, we use the product code structure consisting of a constant rate LDPC/CRC code across the rows of the `blocks' of source data and an erasure-correction systematic Reed-Solomon (RS) code as the column code. In both the schemes introduced here, we use fixed-length source packets protected with unequal forward error correction coding ensuring a strictly decreasing protection across the bitstream. A Rayleigh flat-fading channel with additive white Gaussian noise (AWGN) is modeled for the transmission. The rate-distortion optimization algorithm is developed and carried out for the selection of source coding and channel coding rates using Lagrangian optimization. The experimental results demonstrate the effectiveness of this system under different wireless channel conditions and both the proposed methods (LDPC+RCPC/CRC and RS+LDPC/CRC) outperform the more conventional schemes such as those employing RCPC/CRC.

Error floor behavior study of LDPC codes for concatenated codes design

NASA Astrophysics Data System (ADS)

Chen, Weigang; Yin, Liuguo; Lu, Jianhua

2007-11-01

Error floor behavior of low-density parity-check (LDPC) codes using quantized decoding algorithms is statistically studied with experimental results on a hardware evaluation platform. The results present the distribution of the residual errors after decoding failure and reveal that the number of residual error bits in a codeword is usually very small using quantized sum-product (SP) algorithm. Therefore, LDPC code may serve as the inner code in a concatenated coding system with a high code rate outer code and thus an ultra low error floor can be achieved. This conclusion is also verified by the experimental results.

Non-binary LDPC-coded modulation for high-speed optical metro networks with backpropagation

NASA Astrophysics Data System (ADS)

Arabaci, Murat; Djordjevic, Ivan B.; Saunders, Ross; Marcoccia, Roberto M.

2010-01-01

To simultaneously mitigate the linear and nonlinear channel impairments in high-speed optical communications, we propose the use of non-binary low-density-parity-check-coded modulation in combination with a coarse backpropagation method. By employing backpropagation, we reduce the memory in the channel and in return obtain significant reductions in the complexity of the channel equalizer which is exponentially proportional to the channel memory. We then compensate for the remaining channel distortions using forward error correction based on non-binary LDPC codes. We propose non-binary-LDPC-coded modulation scheme because, compared to bit-interleaved binary-LDPC-coded modulation scheme employing turbo equalization, the proposed scheme lowers the computational complexity and latency of the overall system while providing impressively larger coding gains.

Crosstalk eliminating and low-density parity-check codes for photochromic dual-wavelength storage

NASA Astrophysics Data System (ADS)

Wang, Meicong; Xiong, Jianping; Jian, Jiqi; Jia, Huibo

2005-01-01

Multi-wavelength storage is an approach to increase the memory density with the problem of crosstalk to be deal with. We apply Low Density Parity Check (LDPC) codes as error-correcting codes in photochromic dual-wavelength optical storage based on the investigation of LDPC codes in optical data storage. A proper method is applied to reduce the crosstalk and simulation results show that this operation is useful to improve Bit Error Rate (BER) performance. At the same time we can conclude that LDPC codes outperform RS codes in crosstalk channel.

Entanglement-assisted quantum quasicyclic low-density parity-check codes

NASA Astrophysics Data System (ADS)

Hsieh, Min-Hsiu; Brun, Todd A.; Devetak, Igor

2009-03-01

We investigate the construction of quantum low-density parity-check (LDPC) codes from classical quasicyclic (QC) LDPC codes with girth greater than or equal to 6. We have shown that the classical codes in the generalized Calderbank-Skor-Steane construction do not need to satisfy the dual-containing property as long as preshared entanglement is available to both sender and receiver. We can use this to avoid the many four cycles which typically arise in dual-containing LDPC codes. The advantage of such quantum codes comes from the use of efficient decoding algorithms such as sum-product algorithm (SPA). It is well known that in the SPA, cycles of length 4 make successive decoding iterations highly correlated and hence limit the decoding performance. We show the principle of constructing quantum QC-LDPC codes which require only small amounts of initial shared entanglement.

Iterative decoding of SOVA and LDPC product code for bit-patterned media recoding

NASA Astrophysics Data System (ADS)

Jeong, Seongkwon; Lee, Jaejin

2018-05-01

The demand for high-density storage systems has increased due to the exponential growth of data. Bit-patterned media recording (BPMR) is one of the promising technologies to achieve the density of 1Tbit/in2 and higher. To increase the areal density in BPMR, the spacing between islands needs to be reduced, yet this aggravates inter-symbol interference and inter-track interference and degrades the bit error rate performance. In this paper, we propose a decision feedback scheme using low-density parity check (LDPC) product code for BPMR. This scheme can improve the decoding performance using an iterative approach with extrinsic information and log-likelihood ratio value between iterative soft output Viterbi algorithm and LDPC product code. Simulation results show that the proposed LDPC product code can offer 1.8dB and 2.3dB gains over the one LDPC code at the density of 2.5 and 3 Tb/in2, respectively, when bit error rate is 10-6.

Improving soft FEC performance for higher-order modulations via optimized bit channel mappings.

PubMed

Häger, Christian; Amat, Alexandre Graell I; Brännström, Fredrik; Alvarado, Alex; Agrell, Erik

2014-06-16

Soft forward error correction with higher-order modulations is often implemented in practice via the pragmatic bit-interleaved coded modulation paradigm, where a single binary code is mapped to a nonbinary modulation. In this paper, we study the optimization of the mapping of the coded bits to the modulation bits for a polarization-multiplexed fiber-optical system without optical inline dispersion compensation. Our focus is on protograph-based low-density parity-check (LDPC) codes which allow for an efficient hardware implementation, suitable for high-speed optical communications. The optimization is applied to the AR4JA protograph family, and further extended to protograph-based spatially coupled LDPC codes assuming a windowed decoder. Full field simulations via the split-step Fourier method are used to verify the analysis. The results show performance gains of up to 0.25 dB, which translate into a possible extension of the transmission reach by roughly up to 8%, without significantly increasing the system complexity.

Product code optimization for determinate state LDPC decoding in robust image transmission.

PubMed

Thomos, Nikolaos; Boulgouris, Nikolaos V; Strintzis, Michael G

2006-08-01

We propose a novel scheme for error-resilient image transmission. The proposed scheme employs a product coder consisting of low-density parity check (LDPC) codes and Reed-Solomon codes in order to deal effectively with bit errors. The efficiency of the proposed scheme is based on the exploitation of determinate symbols in Tanner graph decoding of LDPC codes and a novel product code optimization technique based on error estimation. Experimental evaluation demonstrates the superiority of the proposed system in comparison to recent state-of-the-art techniques for image transmission.

An efficient decoding for low density parity check codes

NASA Astrophysics Data System (ADS)

Zhao, Ling; Zhang, Xiaolin; Zhu, Manjie

2009-12-01

Low density parity check (LDPC) codes are a class of forward-error-correction codes. They are among the best-known codes capable of achieving low bit error rates (BER) approaching Shannon's capacity limit. Recently, LDPC codes have been adopted by the European Digital Video Broadcasting (DVB-S2) standard, and have also been proposed for the emerging IEEE 802.16 fixed and mobile broadband wireless-access standard. The consultative committee for space data system (CCSDS) has also recommended using LDPC codes in the deep space communications and near-earth communications. It is obvious that LDPC codes will be widely used in wired and wireless communication, magnetic recording, optical networking, DVB, and other fields in the near future. Efficient hardware implementation of LDPC codes is of great interest since LDPC codes are being considered for a wide range of applications. This paper presents an efficient partially parallel decoder architecture suited for quasi-cyclic (QC) LDPC codes using Belief propagation algorithm for decoding. Algorithmic transformation and architectural level optimization are incorporated to reduce the critical path. First, analyze the check matrix of LDPC code, to find out the relationship between the row weight and the column weight. And then, the sharing level of the check node updating units (CNU) and the variable node updating units (VNU) are determined according to the relationship. After that, rearrange the CNU and the VNU, and divide them into several smaller parts, with the help of some assistant logic circuit, these smaller parts can be grouped into CNU during the check node update processing and grouped into VNU during the variable node update processing. These smaller parts are called node update kernel units (NKU) and the assistant logic circuit are called node update auxiliary unit (NAU). With NAUs' help, the two steps of iteration operation are completed by NKUs, which brings in great hardware resource reduction. Meanwhile, efficient techniques have been developed to reduce the computation delay of the node processing units and to minimize hardware overhead for parallel processing. This method may be applied not only to regular LDPC codes, but also to the irregular ones. Based on the proposed architectures, a (7493, 6096) irregular QC-LDPC code decoder is described using verilog hardware design language and implemented on Altera field programmable gate array (FPGA) StratixII EP2S130. The implementation results show that over 20% of logic core size can be saved than conventional partially parallel decoder architectures without any performance degradation. If the decoding clock is 100MHz, the proposed decoder can achieve a maximum (source data) decoding throughput of 133 Mb/s at 18 iterations.

Soft-Decision-Data Reshuffle to Mitigate Pulsed Radio Frequency Interference Impact on Low-Density-Parity-Check Code Performance

NASA Technical Reports Server (NTRS)

Ni, Jianjun David

2011-01-01

This presentation briefly discusses a research effort on mitigation techniques of pulsed radio frequency interference (RFI) on a Low-Density-Parity-Check (LDPC) code. This problem is of considerable interest in the context of providing reliable communications to the space vehicle which might suffer severe degradation due to pulsed RFI sources such as large radars. The LDPC code is one of modern forward-error-correction (FEC) codes which have the decoding performance to approach the Shannon Limit. The LDPC code studied here is the AR4JA (2048, 1024) code recommended by the Consultative Committee for Space Data Systems (CCSDS) and it has been chosen for some spacecraft design. Even though this code is designed as a powerful FEC code in the additive white Gaussian noise channel, simulation data and test results show that the performance of this LDPC decoder is severely degraded when exposed to the pulsed RFI specified in the spacecraft s transponder specifications. An analysis work (through modeling and simulation) has been conducted to evaluate the impact of the pulsed RFI and a few implemental techniques have been investigated to mitigate the pulsed RFI impact by reshuffling the soft-decision-data available at the input of the LDPC decoder. The simulation results show that the LDPC decoding performance of codeword error rate (CWER) under pulsed RFI can be improved up to four orders of magnitude through a simple soft-decision-data reshuffle scheme. This study reveals that an error floor of LDPC decoding performance appears around CWER=1E-4 when the proposed technique is applied to mitigate the pulsed RFI impact. The mechanism causing this error floor remains unknown, further investigation is necessary.

On the reduced-complexity of LDPC decoders for ultra-high-speed optical transmission.

PubMed

Djordjevic, Ivan B; Xu, Lei; Wang, Ting

2010-10-25

We propose two reduced-complexity (RC) LDPC decoders, which can be used in combination with large-girth LDPC codes to enable ultra-high-speed serial optical transmission. We show that optimally attenuated RC min-sum sum algorithm performs only 0.46 dB (at BER of 10(-9)) worse than conventional sum-product algorithm, while having lower storage memory requirements and much lower latency. We further study the use of RC LDPC decoding algorithms in multilevel coded modulation with coherent detection and show that with RC decoding algorithms we can achieve the net coding gain larger than 11 dB at BERs below 10(-9).

The application of LDPC code in MIMO-OFDM system

NASA Astrophysics Data System (ADS)

Liu, Ruian; Zeng, Beibei; Chen, Tingting; Liu, Nan; Yin, Ninghao

2018-03-01

The combination of MIMO and OFDM technology has become one of the key technologies of the fourth generation mobile communication., which can overcome the frequency selective fading of wireless channel, increase the system capacity and improve the frequency utilization. Error correcting coding introduced into the system can further improve its performance. LDPC (low density parity check) code is a kind of error correcting code which can improve system reliability and anti-interference ability, and the decoding is simple and easy to operate. This paper mainly discusses the application of LDPC code in MIMO-OFDM system.

Simultaneous chromatic dispersion and PMD compensation by using coded-OFDM and girth-10 LDPC codes.

PubMed

Djordjevic, Ivan B; Xu, Lei; Wang, Ting

2008-07-07

Low-density parity-check (LDPC)-coded orthogonal frequency division multiplexing (OFDM) is studied as an efficient coded modulation scheme suitable for simultaneous chromatic dispersion and polarization mode dispersion (PMD) compensation. We show that, for aggregate rate of 10 Gb/s, accumulated dispersion over 6500 km of SMF and differential group delay of 100 ps can be simultaneously compensated with penalty within 1.5 dB (with respect to the back-to-back configuration) when training sequence based channel estimation and girth-10 LDPC codes of rate 0.8 are employed.

Protograph LDPC Codes Over Burst Erasure Channels

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Dolinar, Sam; Jones, Christopher

2006-01-01

In this paper we design high rate protograph based LDPC codes suitable for binary erasure channels. To simplify the encoder and decoder implementation for high data rate transmission, the structure of codes are based on protographs and circulants. These LDPC codes can improve data link and network layer protocols in support of communication networks. Two classes of codes were designed. One class is designed for large block sizes with an iterative decoding threshold that approaches capacity of binary erasure channels. The other class is designed for short block sizes based on maximizing minimum stopping set size. For high code rates and short blocks the second class outperforms the first class.

Experimental demonstration of the transmission performance for LDPC-coded multiband OFDM ultra-wideband over fiber system

NASA Astrophysics Data System (ADS)

He, Jing; Wen, Xuejie; Chen, Ming; Chen, Lin; Su, Jinshu

2015-01-01

To improve the transmission performance of multiband orthogonal frequency division multiplexing (MB-OFDM) ultra-wideband (UWB) over optical fiber, a pre-coding scheme based on low-density parity-check (LDPC) is adopted and experimentally demonstrated in the intensity-modulation and direct-detection MB-OFDM UWB over fiber system. Meanwhile, a symbol synchronization and pilot-aided channel estimation scheme is implemented on the receiver of the MB-OFDM UWB over fiber system. The experimental results show that the LDPC pre-coding scheme can work effectively in the MB-OFDM UWB over fiber system. After 70 km standard single-mode fiber (SSMF) transmission, at the bit error rate of 1 × 10-3, the receiver sensitivities are improved about 4 dB when the LDPC code rate is 75%.

Construction of type-II QC-LDPC codes with fast encoding based on perfect cyclic difference sets

NASA Astrophysics Data System (ADS)

Li, Ling-xiang; Li, Hai-bing; Li, Ji-bi; Jiang, Hua

2017-09-01

In view of the problems that the encoding complexity of quasi-cyclic low-density parity-check (QC-LDPC) codes is high and the minimum distance is not large enough which leads to the degradation of the error-correction performance, the new irregular type-II QC-LDPC codes based on perfect cyclic difference sets (CDSs) are constructed. The parity check matrices of these type-II QC-LDPC codes consist of the zero matrices with weight of 0, the circulant permutation matrices (CPMs) with weight of 1 and the circulant matrices with weight of 2 (W2CMs). The introduction of W2CMs in parity check matrices makes it possible to achieve the larger minimum distance which can improve the error- correction performance of the codes. The Tanner graphs of these codes have no girth-4, thus they have the excellent decoding convergence characteristics. In addition, because the parity check matrices have the quasi-dual diagonal structure, the fast encoding algorithm can reduce the encoding complexity effectively. Simulation results show that the new type-II QC-LDPC codes can achieve a more excellent error-correction performance and have no error floor phenomenon over the additive white Gaussian noise (AWGN) channel with sum-product algorithm (SPA) iterative decoding.

Unitals and ovals of symmetric block designs in LDPC and space-time coding

NASA Astrophysics Data System (ADS)

Andriamanalimanana, Bruno R.

2004-08-01

An approach to the design of LDPC (low density parity check) error-correction and space-time modulation codes involves starting with known mathematical and combinatorial structures, and deriving code properties from structure properties. This paper reports on an investigation of unital and oval configurations within generic symmetric combinatorial designs, not just classical projective planes, as the underlying structure for classes of space-time LDPC outer codes. Of particular interest are the encoding and iterative (sum-product) decoding gains that these codes may provide. Various small-length cases have been numerically implemented in Java and Matlab for a number of channel models.

High-efficiency Gaussian key reconciliation in continuous variable quantum key distribution

NASA Astrophysics Data System (ADS)

Bai, ZengLiang; Wang, XuYang; Yang, ShenShen; Li, YongMin

2016-01-01

Efficient reconciliation is a crucial step in continuous variable quantum key distribution. The progressive-edge-growth (PEG) algorithm is an efficient method to construct relatively short block length low-density parity-check (LDPC) codes. The qua-sicyclic construction method can extend short block length codes and further eliminate the shortest cycle. In this paper, by combining the PEG algorithm and qua-si-cyclic construction method, we design long block length irregular LDPC codes with high error-correcting capacity. Based on these LDPC codes, we achieve high-efficiency Gaussian key reconciliation with slice recon-ciliation based on multilevel coding/multistage decoding with an efficiency of 93.7%.

A Scalable Architecture of a Structured LDPC Decoder

NASA Technical Reports Server (NTRS)

Lee, Jason Kwok-San; Lee, Benjamin; Thorpe, Jeremy; Andrews, Kenneth; Dolinar, Sam; Hamkins, Jon

2004-01-01

We present a scalable decoding architecture for a certain class of structured LDPC codes. The codes are designed using a small (n,r) protograph that is replicated Z times to produce a decoding graph for a (Z x n, Z x r) code. Using this architecture, we have implemented a decoder for a (4096,2048) LDPC code on a Xilinx Virtex-II 2000 FPGA, and achieved decoding speeds of 31 Mbps with 10 fixed iterations. The implemented message-passing algorithm uses an optimized 3-bit non-uniform quantizer that operates with 0.2dB implementation loss relative to a floating point decoder.

Constructing LDPC Codes from Loop-Free Encoding Modules

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Dolinar, Samuel; Jones, Christopher; Thorpe, Jeremy; Andrews, Kenneth

2009-01-01

A method of constructing certain low-density parity-check (LDPC) codes by use of relatively simple loop-free coding modules has been developed. The subclasses of LDPC codes to which the method applies includes accumulate-repeat-accumulate (ARA) codes, accumulate-repeat-check-accumulate codes, and the codes described in Accumulate-Repeat-Accumulate-Accumulate Codes (NPO-41305), NASA Tech Briefs, Vol. 31, No. 9 (September 2007), page 90. All of the affected codes can be characterized as serial/parallel (hybrid) concatenations of such relatively simple modules as accumulators, repetition codes, differentiators, and punctured single-parity check codes. These are error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels. These codes can also be characterized as hybrid turbolike codes that have projected graph or protograph representations (for example see figure); these characteristics make it possible to design high-speed iterative decoders that utilize belief-propagation algorithms. The present method comprises two related submethods for constructing LDPC codes from simple loop-free modules with circulant permutations. The first submethod is an iterative encoding method based on the erasure-decoding algorithm. The computations required by this method are well organized because they involve a parity-check matrix having a block-circulant structure. The second submethod involves the use of block-circulant generator matrices. The encoders of this method are very similar to those of recursive convolutional codes. Some encoders according to this second submethod have been implemented in a small field-programmable gate array that operates at a speed of 100 megasymbols per second. By use of density evolution (a computational- simulation technique for analyzing performances of LDPC codes), it has been shown through some examples that as the block size goes to infinity, low iterative decoding thresholds close to channel capacity limits can be achieved for the codes of the type in question having low maximum variable node degrees. The decoding thresholds in these examples are lower than those of the best-known unstructured irregular LDPC codes constrained to have the same maximum node degrees. Furthermore, the present method enables the construction of codes of any desired rate with thresholds that stay uniformly close to their respective channel capacity thresholds.

Low complexity Reed-Solomon-based low-density parity-check design for software defined optical transmission system based on adaptive puncturing decoding algorithm

NASA Astrophysics Data System (ADS)

Pan, Xiaolong; Liu, Bo; Zheng, Jianglong; Tian, Qinghua

2016-08-01

We propose and demonstrate a low complexity Reed-Solomon-based low-density parity-check (RS-LDPC) code with adaptive puncturing decoding algorithm for elastic optical transmission system. Partial received codes and the relevant column in parity-check matrix can be punctured to reduce the calculation complexity by adaptive parity-check matrix during decoding process. The results show that the complexity of the proposed decoding algorithm is reduced by 30% compared with the regular RS-LDPC system. The optimized code rate of the RS-LDPC code can be obtained after five times iteration.

Structured Low-Density Parity-Check Codes with Bandwidth Efficient Modulation

NASA Technical Reports Server (NTRS)

Cheng, Michael K.; Divsalar, Dariush; Duy, Stephanie

2009-01-01

In this work, we study the performance of structured Low-Density Parity-Check (LDPC) Codes together with bandwidth efficient modulations. We consider protograph-based LDPC codes that facilitate high-speed hardware implementations and have minimum distances that grow linearly with block sizes. We cover various higher- order modulations such as 8-PSK, 16-APSK, and 16-QAM. During demodulation, a demapper transforms the received in-phase and quadrature samples into reliability information that feeds the binary LDPC decoder. We will compare various low-complexity demappers and provide simulation results for assorted coded-modulation combinations on the additive white Gaussian noise and independent Rayleigh fading channels.

Accumulate repeat accumulate codes

NASA Technical Reports Server (NTRS)

Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

2004-01-01

In this paper we propose an innovative channel coding scheme called 'Accumulate Repeat Accumulate codes' (ARA). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes, thus belief propagation can be used for iterative decoding of ARA codes on a graph. The structure of encoder for this class can be viewed as precoded Repeat Accumulate (RA) code or as precoded Irregular Repeat Accumulate (IRA) code, where simply an accumulator is chosen as a precoder. Thus ARA codes have simple, and very fast encoder structure when they representing LDPC codes. Based on density evolution for LDPC codes through some examples for ARA codes, we show that for maximum variable node degree 5 a minimum bit SNR as low as 0.08 dB from channel capacity for rate 1/2 can be achieved as the block size goes to infinity. Thus based on fixed low maximum variable node degree, its threshold outperforms not only the RA and IRA codes but also the best known LDPC codes with the dame maximum node degree. Furthermore by puncturing the accumulators any desired high rate codes close to code rate 1 can be obtained with thresholds that stay close to the channel capacity thresholds uniformly. Iterative decoding simulation results are provided. The ARA codes also have projected graph or protograph representation that allows for high speed decoder implementation.

PMD compensation in fiber-optic communication systems with direct detection using LDPC-coded OFDM.

PubMed

Djordjevic, Ivan B

2007-04-02

The possibility of polarization-mode dispersion (PMD) compensation in fiber-optic communication systems with direct detection using a simple channel estimation technique and low-density parity-check (LDPC)-coded orthogonal frequency division multiplexing (OFDM) is demonstrated. It is shown that even for differential group delay (DGD) of 4/BW (BW is the OFDM signal bandwidth), the degradation due to the first-order PMD can be completely compensated for. Two classes of LDPC codes designed based on two different combinatorial objects (difference systems and product of combinatorial designs) suitable for use in PMD compensation are introduced.

A modified non-binary LDPC scheme based on watermark symbols in high speed optical transmission systems

NASA Astrophysics Data System (ADS)

Wang, Liming; Qiao, Yaojun; Yu, Qian; Zhang, Wenbo

2016-04-01

We introduce a watermark non-binary low-density parity check code (NB-LDPC) scheme, which can estimate the time-varying noise variance by using prior information of watermark symbols, to improve the performance of NB-LDPC codes. And compared with the prior-art counterpart, the watermark scheme can bring about 0.25 dB improvement in net coding gain (NCG) at bit error rate (BER) of 1e-6 and 36.8-81% reduction of the iteration numbers. Obviously, the proposed scheme shows great potential in terms of error correction performance and decoding efficiency.

Performance Evaluation of LDPC Coding and Iterative Decoding System in BPM R/W Channel Affected by Head Field Gradient, Media SFD and Demagnetization Field

NASA Astrophysics Data System (ADS)

Nakamura, Yasuaki; Okamoto, Yoshihiro; Osawa, Hisashi; Aoi, Hajime; Muraoka, Hiroaki

We evaluate the performance of the write-margin for the low-density parity-check (LDPC) coding and iterative decoding system in the bit-patterned media (BPM) R/W channel affected by the write-head field gradient, the media switching field distribution (SFD), the demagnetization field from adjacent islands and the island position deviation. It is clarified that the LDPC coding and iterative decoding system in R/W channel using BPM at 3 Tbit/inch2 has a write-margin of about 20%.

Cooperative optimization and their application in LDPC codes

NASA Astrophysics Data System (ADS)

Chen, Ke; Rong, Jian; Zhong, Xiaochun

2008-10-01

Cooperative optimization is a new way for finding global optima of complicated functions of many variables. The proposed algorithm is a class of message passing algorithms and has solid theory foundations. It can achieve good coding gains over the sum-product algorithm for LDPC codes. For (6561, 4096) LDPC codes, the proposed algorithm can achieve 2.0 dB gains over the sum-product algorithm at BER of 4×10-7. The decoding complexity of the proposed algorithm is lower than the sum-product algorithm can do; furthermore, the former can achieve much lower error floor than the latter can do after the Eb / No is higher than 1.8 dB.

A Low-Complexity Euclidean Orthogonal LDPC Architecture for Low Power Applications.

PubMed

Revathy, M; Saravanan, R

2015-01-01

Low-density parity-check (LDPC) codes have been implemented in latest digital video broadcasting, broadband wireless access (WiMax), and fourth generation of wireless standards. In this paper, we have proposed a high efficient low-density parity-check code (LDPC) decoder architecture for low power applications. This study also considers the design and analysis of check node and variable node units and Euclidean orthogonal generator in LDPC decoder architecture. The Euclidean orthogonal generator is used to reduce the error rate of the proposed LDPC architecture, which can be incorporated between check and variable node architecture. This proposed decoder design is synthesized on Xilinx 9.2i platform and simulated using Modelsim, which is targeted to 45 nm devices. Synthesis report proves that the proposed architecture greatly reduces the power consumption and hardware utilizations on comparing with different conventional architectures.

DNA Barcoding through Quaternary LDPC Codes

PubMed Central

Tapia, Elizabeth; Spetale, Flavio; Krsticevic, Flavia; Angelone, Laura; Bulacio, Pilar

2015-01-01

For many parallel applications of Next-Generation Sequencing (NGS) technologies short barcodes able to accurately multiplex a large number of samples are demanded. To address these competitive requirements, the use of error-correcting codes is advised. Current barcoding systems are mostly built from short random error-correcting codes, a feature that strongly limits their multiplexing accuracy and experimental scalability. To overcome these problems on sequencing systems impaired by mismatch errors, the alternative use of binary BCH and pseudo-quaternary Hamming codes has been proposed. However, these codes either fail to provide a fine-scale with regard to size of barcodes (BCH) or have intrinsic poor error correcting abilities (Hamming). Here, the design of barcodes from shortened binary BCH codes and quaternary Low Density Parity Check (LDPC) codes is introduced. Simulation results show that although accurate barcoding systems of high multiplexing capacity can be obtained with any of these codes, using quaternary LDPC codes may be particularly advantageous due to the lower rates of read losses and undetected sample misidentification errors. Even at mismatch error rates of 10−2 per base, 24-nt LDPC barcodes can be used to multiplex roughly 2000 samples with a sample misidentification error rate in the order of 10−9 at the expense of a rate of read losses just in the order of 10−6. PMID:26492348

DNA Barcoding through Quaternary LDPC Codes.

PubMed

Tapia, Elizabeth; Spetale, Flavio; Krsticevic, Flavia; Angelone, Laura; Bulacio, Pilar

2015-01-01

For many parallel applications of Next-Generation Sequencing (NGS) technologies short barcodes able to accurately multiplex a large number of samples are demanded. To address these competitive requirements, the use of error-correcting codes is advised. Current barcoding systems are mostly built from short random error-correcting codes, a feature that strongly limits their multiplexing accuracy and experimental scalability. To overcome these problems on sequencing systems impaired by mismatch errors, the alternative use of binary BCH and pseudo-quaternary Hamming codes has been proposed. However, these codes either fail to provide a fine-scale with regard to size of barcodes (BCH) or have intrinsic poor error correcting abilities (Hamming). Here, the design of barcodes from shortened binary BCH codes and quaternary Low Density Parity Check (LDPC) codes is introduced. Simulation results show that although accurate barcoding systems of high multiplexing capacity can be obtained with any of these codes, using quaternary LDPC codes may be particularly advantageous due to the lower rates of read losses and undetected sample misidentification errors. Even at mismatch error rates of 10(-2) per base, 24-nt LDPC barcodes can be used to multiplex roughly 2000 samples with a sample misidentification error rate in the order of 10(-9) at the expense of a rate of read losses just in the order of 10(-6).

LDPC-PPM Coding Scheme for Optical Communication

NASA Technical Reports Server (NTRS)

Barsoum, Maged; Moision, Bruce; Divsalar, Dariush; Fitz, Michael

2009-01-01

In a proposed coding-and-modulation/demodulation-and-decoding scheme for a free-space optical communication system, an error-correcting code of the low-density parity-check (LDPC) type would be concatenated with a modulation code that consists of a mapping of bits to pulse-position-modulation (PPM) symbols. Hence, the scheme is denoted LDPC-PPM. This scheme could be considered a competitor of a related prior scheme in which an outer convolutional error-correcting code is concatenated with an interleaving operation, a bit-accumulation operation, and a PPM inner code. Both the prior and present schemes can be characterized as serially concatenated pulse-position modulation (SCPPM) coding schemes. Figure 1 represents a free-space optical communication system based on either the present LDPC-PPM scheme or the prior SCPPM scheme. At the transmitting terminal, the original data (u) are processed by an encoder into blocks of bits (a), and the encoded data are mapped to PPM of an optical signal (c). For the purpose of design and analysis, the optical channel in which the PPM signal propagates is modeled as a Poisson point process. At the receiving terminal, the arriving optical signal (y) is demodulated to obtain an estimate (a^) of the coded data, which is then processed by a decoder to obtain an estimate (u^) of the original data.

LDPC-coded MIMO optical communication over the atmospheric turbulence channel using Q-ary pulse-position modulation.

PubMed

Djordjevic, Ivan B

2007-08-06

We describe a coded power-efficient transmission scheme based on repetition MIMO principle suitable for communication over the atmospheric turbulence channel, and determine its channel capacity. The proposed scheme employs the Q-ary pulse-position modulation. We further study how to approach the channel capacity limits using low-density parity-check (LDPC) codes. Component LDPC codes are designed using the concept of pairwise-balanced designs. Contrary to the several recent publications, bit-error rates and channel capacities are reported assuming non-ideal photodetection. The atmospheric turbulence channel is modeled using the Gamma-Gamma distribution function due to Al-Habash et al. Excellent bit-error rate performance improvement, over uncoded case, is found.

A Low-Complexity Euclidean Orthogonal LDPC Architecture for Low Power Applications

PubMed Central

Revathy, M.; Saravanan, R.

2015-01-01

Low-density parity-check (LDPC) codes have been implemented in latest digital video broadcasting, broadband wireless access (WiMax), and fourth generation of wireless standards. In this paper, we have proposed a high efficient low-density parity-check code (LDPC) decoder architecture for low power applications. This study also considers the design and analysis of check node and variable node units and Euclidean orthogonal generator in LDPC decoder architecture. The Euclidean orthogonal generator is used to reduce the error rate of the proposed LDPC architecture, which can be incorporated between check and variable node architecture. This proposed decoder design is synthesized on Xilinx 9.2i platform and simulated using Modelsim, which is targeted to 45 nm devices. Synthesis report proves that the proposed architecture greatly reduces the power consumption and hardware utilizations on comparing with different conventional architectures. PMID:26065017

Neural network decoder for quantum error correcting codes

NASA Astrophysics Data System (ADS)

Krastanov, Stefan; Jiang, Liang

Artificial neural networks form a family of extremely powerful - albeit still poorly understood - tools used in anything from image and sound recognition through text generation to, in our case, decoding. We present a straightforward Recurrent Neural Network architecture capable of deducing the correcting procedure for a quantum error-correcting code from a set of repeated stabilizer measurements. We discuss the fault-tolerance of our scheme and the cost of training the neural network for a system of a realistic size. Such decoders are especially interesting when applied to codes, like the quantum LDPC codes, that lack known efficient decoding schemes.

Optimal Codes for the Burst Erasure Channel

NASA Technical Reports Server (NTRS)

Hamkins, Jon

2010-01-01

Deep space communications over noisy channels lead to certain packets that are not decodable. These packets leave gaps, or bursts of erasures, in the data stream. Burst erasure correcting codes overcome this problem. These are forward erasure correcting codes that allow one to recover the missing gaps of data. Much of the recent work on this topic concentrated on Low-Density Parity-Check (LDPC) codes. These are more complicated to encode and decode than Single Parity Check (SPC) codes or Reed-Solomon (RS) codes, and so far have not been able to achieve the theoretical limit for burst erasure protection. A block interleaved maximum distance separable (MDS) code (e.g., an SPC or RS code) offers near-optimal burst erasure protection, in the sense that no other scheme of equal total transmission length and code rate could improve the guaranteed correctible burst erasure length by more than one symbol. The optimality does not depend on the length of the code, i.e., a short MDS code block interleaved to a given length would perform as well as a longer MDS code interleaved to the same overall length. As a result, this approach offers lower decoding complexity with better burst erasure protection compared to other recent designs for the burst erasure channel (e.g., LDPC codes). A limitation of the design is its lack of robustness to channels that have impairments other than burst erasures (e.g., additive white Gaussian noise), making its application best suited for correcting data erasures in layers above the physical layer. The efficiency of a burst erasure code is the length of its burst erasure correction capability divided by the theoretical upper limit on this length. The inefficiency is one minus the efficiency. The illustration compares the inefficiency of interleaved RS codes to Quasi-Cyclic (QC) LDPC codes, Euclidean Geometry (EG) LDPC codes, extended Irregular Repeat Accumulate (eIRA) codes, array codes, and random LDPC codes previously proposed for burst erasure protection. As can be seen, the simple interleaved RS codes have substantially lower inefficiency over a wide range of transmission lengths.

Bounded-Angle Iterative Decoding of LDPC Codes

NASA Technical Reports Server (NTRS)

Dolinar, Samuel; Andrews, Kenneth; Pollara, Fabrizio; Divsalar, Dariush

2009-01-01

Bounded-angle iterative decoding is a modified version of conventional iterative decoding, conceived as a means of reducing undetected-error rates for short low-density parity-check (LDPC) codes. For a given code, bounded-angle iterative decoding can be implemented by means of a simple modification of the decoder algorithm, without redesigning the code. Bounded-angle iterative decoding is based on a representation of received words and code words as vectors in an n-dimensional Euclidean space (where n is an integer).

Short-Block Protograph-Based LDPC Codes

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Dolinar, Samuel; Jones, Christopher

2010-01-01

Short-block low-density parity-check (LDPC) codes of a special type are intended to be especially well suited for potential applications that include transmission of command and control data, cellular telephony, data communications in wireless local area networks, and satellite data communications. [In general, LDPC codes belong to a class of error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels.] The codes of the present special type exhibit low error floors, low bit and frame error rates, and low latency (in comparison with related prior codes). These codes also achieve low maximum rate of undetected errors over all signal-to-noise ratios, without requiring the use of cyclic redundancy checks, which would significantly increase the overhead for short blocks. These codes have protograph representations; this is advantageous in that, for reasons that exceed the scope of this article, the applicability of protograph representations makes it possible to design highspeed iterative decoders that utilize belief- propagation algorithms.

LDPC Codes--Structural Analysis and Decoding Techniques

ERIC Educational Resources Information Center

Zhang, Xiaojie

2012-01-01

Low-density parity-check (LDPC) codes have been the focus of much research over the past decade thanks to their near Shannon limit performance and to their efficient message-passing (MP) decoding algorithms. However, the error floor phenomenon observed in MP decoding, which manifests itself as an abrupt change in the slope of the error-rate curve,…

Rate-Compatible Protograph LDPC Codes

NASA Technical Reports Server (NTRS)

Nguyen, Thuy V. (Inventor); Nosratinia, Aria (Inventor); Divsalar, Dariush (Inventor)

2014-01-01

Digital communication coding methods resulting in rate-compatible low density parity-check (LDPC) codes built from protographs. Described digital coding methods start with a desired code rate and a selection of the numbers of variable nodes and check nodes to be used in the protograph. Constraints are set to satisfy a linear minimum distance growth property for the protograph. All possible edges in the graph are searched for the minimum iterative decoding threshold and the protograph with the lowest iterative decoding threshold is selected. Protographs designed in this manner are used in decode and forward relay channels.

Using LDPC Code Constraints to Aid Recovery of Symbol Timing

NASA Technical Reports Server (NTRS)

Jones, Christopher; Villasnor, John; Lee, Dong-U; Vales, Esteban

2008-01-01

A method of utilizing information available in the constraints imposed by a low-density parity-check (LDPC) code has been proposed as a means of aiding the recovery of symbol timing in the reception of a binary-phase-shift-keying (BPSK) signal representing such a code in the presence of noise, timing error, and/or Doppler shift between the transmitter and the receiver. This method and the receiver architecture in which it would be implemented belong to a class of timing-recovery methods and corresponding receiver architectures characterized as pilotless in that they do not require transmission and reception of pilot signals. Acquisition and tracking of a signal of the type described above have traditionally been performed upstream of, and independently of, decoding and have typically involved utilization of a phase-locked loop (PLL). However, the LDPC decoding process, which is iterative, provides information that can be fed back to the timing-recovery receiver circuits to improve performance significantly over that attainable in the absence of such feedback. Prior methods of coupling LDPC decoding with timing recovery had focused on the use of output code words produced as the iterations progress. In contrast, in the present method, one exploits the information available from the metrics computed for the constraint nodes of an LDPC code during the decoding process. In addition, the method involves the use of a waveform model that captures, better than do the waveform models of the prior methods, distortions introduced by receiver timing errors and transmitter/ receiver motions. An LDPC code is commonly represented by use of a bipartite graph containing two sets of nodes. In the graph corresponding to an (n,k) code, the n variable nodes correspond to the code word symbols and the n-k constraint nodes represent the constraints that the code places on the variable nodes in order for them to form a valid code word. The decoding procedure involves iterative computation of values associated with these nodes. A constraint node represents a parity-check equation using a set of variable nodes as inputs. A valid decoded code word is obtained if all parity-check equations are satisfied. After each iteration, the metrics associated with each constraint node can be evaluated to determine the status of the associated parity check. Heretofore, normally, these metrics would be utilized only within the LDPC decoding process to assess whether or not variable nodes had converged to a codeword. In the present method, it is recognized that these metrics can be used to determine accuracy of the timing estimates used in acquiring the sampled data that constitute the input to the LDPC decoder. In fact, the number of constraints that are satisfied exhibits a peak near the optimal timing estimate. Coarse timing estimation (or first-stage estimation as described below) is found via a parametric search for this peak. The present method calls for a two-stage receiver architecture illustrated in the figure. The first stage would correct large time delays and frequency offsets; the second stage would track random walks and correct residual time and frequency offsets. In the first stage, constraint-node feedback from the LDPC decoder would be employed in a search algorithm in which the searches would be performed in successively narrower windows to find the correct time delay and/or frequency offset. The second stage would include a conventional first-order PLL with a decision-aided timing-error detector that would utilize, as its decision aid, decoded symbols from the LDPC decoder. The method has been tested by means of computational simulations in cases involving various timing and frequency errors. The results of the simulations ined in the ideal case of perfect timing in the receiver.

PSEUDO-CODEWORD LANDSCAPE

DOE Office of Scientific and Technical Information (OSTI.GOV)

CHERTKOV, MICHAEL; STEPANOV, MIKHAIL

2007-01-10

The authors discuss performance of Low-Density-Parity-Check (LDPC) codes decoded by Linear Programming (LP) decoding at moderate and large Signal-to-Noise-Ratios (SNR). Frame-Error-Rate (FER) dependence on SNR and the noise space landscape of the coding/decoding scheme are analyzed by a combination of the previously introduced instanton/pseudo-codeword-search method and a new 'dendro' trick. To reduce complexity of the LP decoding for a code with high-degree checks, {ge} 5, they introduce its dendro-LDPC counterpart, that is the code performing identifically to the original one under Maximum-A-Posteriori (MAP) decoding but having reduced (down to three) check connectivity degree. Analyzing number of popular LDPC codes andmore » their dendro versions performing over the Additive-White-Gaussian-Noise (AWGN) channel, they observed two qualitatively different regimes: (i) error-floor sets early, at relatively low SNR, and (ii) FER decays with SNR increase faster at moderate SNR than at the largest SNR. They explain these regimes in terms of the pseudo-codeword spectra of the codes.« less

FPGA-based LDPC-coded APSK for optical communication systems.

PubMed

Zou, Ding; Lin, Changyu; Djordjevic, Ivan B

2017-02-20

In this paper, with the aid of mutual information and generalized mutual information (GMI) capacity analyses, it is shown that the geometrically shaped APSK that mimics an optimal Gaussian distribution with equiprobable signaling together with the corresponding gray-mapping rules can approach the Shannon limit closer than conventional quadrature amplitude modulation (QAM) at certain range of FEC overhead for both 16-APSK and 64-APSK. The field programmable gate array (FPGA) based LDPC-coded APSK emulation is conducted on block interleaver-based and bit interleaver-based systems; the results verify a significant improvement in hardware efficient bit interleaver-based systems. In bit interleaver-based emulation, the LDPC-coded 64-APSK outperforms 64-QAM, in terms of symbol signal-to-noise ratio (SNR), by 0.1 dB, 0.2 dB, and 0.3 dB at spectral efficiencies of 4.8, 4.5, and 4.2 b/s/Hz, respectively. It is found by emulation that LDPC-coded 64-APSK for spectral efficiencies of 4.8, 4.5, and 4.2 b/s/Hz is 1.6 dB, 1.7 dB, and 2.2 dB away from the GMI capacity.

Channel coding for underwater acoustic single-carrier CDMA communication system

NASA Astrophysics Data System (ADS)

Liu, Lanjun; Zhang, Yonglei; Zhang, Pengcheng; Zhou, Lin; Niu, Jiong

2017-01-01

CDMA is an effective multiple access protocol for underwater acoustic networks, and channel coding can effectively reduce the bit error rate (BER) of the underwater acoustic communication system. For the requirements of underwater acoustic mobile networks based on CDMA, an underwater acoustic single-carrier CDMA communication system (UWA/SCCDMA) based on the direct-sequence spread spectrum is proposed, and its channel coding scheme is studied based on convolution, RA, Turbo and LDPC coding respectively. The implementation steps of the Viterbi algorithm of convolutional coding, BP and minimum sum algorithms of RA coding, Log-MAP and SOVA algorithms of Turbo coding, and sum-product algorithm of LDPC coding are given. An UWA/SCCDMA simulation system based on Matlab is designed. Simulation results show that the UWA/SCCDMA based on RA, Turbo and LDPC coding have good performance such that the communication BER is all less than 10-6 in the underwater acoustic channel with low signal to noise ratio (SNR) from -12 dB to -10dB, which is about 2 orders of magnitude lower than that of the convolutional coding. The system based on Turbo coding with Log-MAP algorithm has the best performance.

Encoders for block-circulant LDPC codes

NASA Technical Reports Server (NTRS)

Andrews, Kenneth; Dolinar, Sam; Thorpe, Jeremy

2005-01-01

In this paper, we present two encoding methods for block-circulant LDPC codes. The first is an iterative encoding method based on the erasure decoding algorithm, and the computations required are well organized due to the block-circulant structure of the parity check matrix. The second method uses block-circulant generator matrices, and the encoders are very similar to those for recursive convolutional codes. Some encoders of the second type have been implemented in a small Field Programmable Gate Array (FPGA) and operate at 100 Msymbols/second.

Strategic and Tactical Decision-Making Under Uncertainty

DTIC Science & Technology

2006-01-03

message passing algorithms. In recent work we applied this method to the problem of joint decoding of a low-density parity-check ( LDPC ) code and a partial...Joint Decoding of LDPC Codes and Partial-Response Channels." IEEE Transactions on Communications. Vol. 54, No. 7, 1149-1153, 2006. P. Pakzad and V...Michael I. Jordan PAGES U U U SAPR 20 19b. TELEPHONE NUMBER (Include area code ) 510/642-3806 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18

Study regarding the density evolution of messages and the characteristic functions associated of a LDPC code

NASA Astrophysics Data System (ADS)

Drăghici, S.; Proştean, O.; Răduca, E.; Haţiegan, C.; Hălălae, I.; Pădureanu, I.; Nedeloni, M.; (Barboni Haţiegan, L.

2017-01-01

In this paper a method with which a set of characteristic functions are associated to a LDPC code is shown and also functions that represent the evolution density of messages that go along the edges of a Tanner graph. Graphic representations of the density evolution are shown respectively the study and simulation of likelihood threshold that render asymptotic boundaries between which there are decodable codes were made using MathCad V14 software.

Pilotless Frame Synchronization Using LDPC Code Constraints

NASA Technical Reports Server (NTRS)

Jones, Christopher; Vissasenor, John

2009-01-01

A method of pilotless frame synchronization has been devised for low- density parity-check (LDPC) codes. In pilotless frame synchronization , there are no pilot symbols; instead, the offset is estimated by ex ploiting selected aspects of the structure of the code. The advantag e of pilotless frame synchronization is that the bandwidth of the sig nal is reduced by an amount associated with elimination of the pilot symbols. The disadvantage is an increase in the amount of receiver data processing needed for frame synchronization.

Bilayer Protograph Codes for Half-Duplex Relay Channels

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; VanNguyen, Thuy; Nosratinia, Aria

2013-01-01

Direct to Earth return links are limited by the size and power of lander devices. A standard alternative is provided by a two-hops return link: a proximity link (from lander to orbiter relay) and a deep-space link (from orbiter relay to Earth). Although direct to Earth return links are limited by the size and power of lander devices, using an additional link and a proposed coding for relay channels, one can obtain a more reliable signal. Although significant progress has been made in the relay coding problem, existing codes must be painstakingly optimized to match to a single set of channel conditions, many of them do not offer easy encoding, and most of them do not have structured design. A high-performing LDPC (low-density parity-check) code for the relay channel addresses simultaneously two important issues: a code structure that allows low encoding complexity, and a flexible rate-compatible code that allows matching to various channel conditions. Most of the previous high-performance LDPC codes for the relay channel are tightly optimized for a given channel quality, and are not easily adapted without extensive re-optimization for various channel conditions. This code for the relay channel combines structured design and easy encoding with rate compatibility to allow adaptation to the three links involved in the relay channel, and furthermore offers very good performance. The proposed code is constructed by synthesizing a bilayer structure with a pro to graph. In addition to the contribution to relay encoding, an improved family of protograph codes was produced for the point-to-point AWGN (additive white Gaussian noise) channel whose high-rate members enjoy thresholds that are within 0.07 dB of capacity. These LDPC relay codes address three important issues in an integrative manner: low encoding complexity, modular structure allowing for easy design, and rate compatibility so that the code can be easily matched to a variety of channel conditions without extensive re-optimization. The main problem of half-duplex relay coding can be reduced to the simultaneous design of two codes at two rates and two SNRs (signal-to-noise ratios), such that one is a subset of the other. This problem can be addressed by forceful optimization, but a clever method of addressing this problem is via the bilayer lengthened (BL) LDPC structure. This method uses a bilayer Tanner graph to make the two codes while using a concept of "parity forwarding" with subsequent successive decoding that removes the need to directly address the issue of uneven SNRs among the symbols of a given codeword. This method is attractive in that it addresses some of the main issues in the design of relay codes, but it does not by itself give rise to highly structured codes with simple encoding, nor does it give rate-compatible codes. The main contribution of this work is to construct a class of codes that simultaneously possess a bilayer parity- forwarding mechanism, while also benefiting from the properties of protograph codes having an easy encoding, a modular design, and being a rate-compatible code.

Received response based heuristic LDPC code for short-range non-line-of-sight ultraviolet communication.

PubMed

Qin, Heng; Zuo, Yong; Zhang, Dong; Li, Yinghui; Wu, Jian

2017-03-06

Through slight modification on typical photon multiplier tube (PMT) receiver output statistics, a generalized received response model considering both scattered propagation and random detection is presented to investigate the impact of inter-symbol interference (ISI) on link data rate of short-range non-line-of-sight (NLOS) ultraviolet communication. Good agreement with the experimental results by numerical simulation is shown. Based on the received response characteristics, a heuristic check matrix construction algorithm of low-density-parity-check (LDPC) code is further proposed to approach the data rate bound derived in a delayed sampling (DS) binary pulse position modulation (PPM) system. Compared to conventional LDPC coding methods, better bit error ratio (BER) below 1E-05 is achieved for short-range NLOS UVC systems operating at data rate of 2Mbps.

Irreducible normalizer operators and thresholds for degenerate quantum codes with sublinear distances

NASA Astrophysics Data System (ADS)

Pryadko, Leonid P.; Dumer, Ilya; Kovalev, Alexey A.

2015-03-01

We construct a lower (existence) bound for the threshold of scalable quantum computation which is applicable to all stabilizer codes, including degenerate quantum codes with sublinear distance scaling. The threshold is based on enumerating irreducible operators in the normalizer of the code, i.e., those that cannot be decomposed into a product of two such operators with non-overlapping support. For quantum LDPC codes with logarithmic or power-law distances, we get threshold values which are parametrically better than the existing analytical bound based on percolation. The new bound also gives a finite threshold when applied to other families of degenerate quantum codes, e.g., the concatenated codes. This research was supported in part by the NSF Grant PHY-1416578 and by the ARO Grant W911NF-11-1-0027.

Design and implementation of a channel decoder with LDPC code

NASA Astrophysics Data System (ADS)

Hu, Diqing; Wang, Peng; Wang, Jianzong; Li, Tianquan

2008-12-01

Because Toshiba quit the competition, there is only one standard of blue-ray disc: BLU-RAY DISC, which satisfies the demands of high-density video programs. But almost all the patents are gotten by big companies such as Sony, Philips. As a result we must pay much for these patents when our productions use BD. As our own high-density optical disk storage system, Next-Generation Versatile Disc(NVD) which proposes a new data format and error correction code with independent intellectual property rights and high cost performance owns higher coding efficiency than DVD and 12GB which could meet the demands of playing the high-density video programs. In this paper, we develop Low-Density Parity-Check Codes (LDPC): a new channel encoding process and application scheme using Q-matrix based on LDPC encoding has application in NVD's channel decoder. And combined with the embedded system portable feature of SOPC system, we have completed all the decoding modules by FPGA. In the NVD experiment environment, tests are done. Though there are collisions between LDPC and Run-Length-Limited modulation codes (RLL) which are used in optical storage system frequently, the system is provided as a suitable solution. At the same time, it overcomes the defects of the instability and inextensibility, which occurred in the former decoding system of NVD--it was implemented by hardware.

Characterization of LDPC-coded orbital angular momentum modes transmission and multiplexing over a 50-km fiber.

PubMed

Wang, Andong; Zhu, Long; Chen, Shi; Du, Cheng; Mo, Qi; Wang, Jian

2016-05-30

Mode-division multiplexing over fibers has attracted increasing attention over the last few years as a potential solution to further increase fiber transmission capacity. In this paper, we demonstrate the viability of orbital angular momentum (OAM) modes transmission over a 50-km few-mode fiber (FMF). By analyzing mode properties of eigen modes in an FMF, we study the inner mode group differential modal delay (DMD) in FMF, which may influence the transmission capacity in long-distance OAM modes transmission and multiplexing. To mitigate the impact of large inner mode group DMD in long-distance fiber-based OAM modes transmission, we use low-density parity-check (LDPC) codes to increase the system reliability. By evaluating the performance of LDPC-coded single OAM mode transmission over 50-km fiber, significant coding gains of >4 dB, 8 dB and 14 dB are demonstrated for 1-Gbaud, 2-Gbaud and 5-Gbaud quadrature phase-shift keying (QPSK) signals, respectively. Furthermore, in order to verify and compare the influence of DMD in long-distance fiber transmission, single OAM mode transmission over 10-km FMF is also demonstrated in the experiment. Finally, we experimentally demonstrate OAM multiplexing and transmission over a 50-km FMF using LDPC-coded 1-Gbaud QPSK signals to compensate the influence of mode crosstalk and DMD in the 50 km FMF.

On the reduced-complexity of LDPC decoders for beyond 400 Gb/s serial optical transmission

NASA Astrophysics Data System (ADS)

Djordjevic, Ivan B.; Xu, Lei; Wang, Ting

2010-12-01

Two reduced-complexity (RC) LDPC decoders are proposed, which can be used in combination with large-girth LDPC codes to enable beyond 400 Gb/s serial optical transmission. We show that optimally attenuated RC min-sum sum algorithm performs only 0.45 dB worse than conventional sum-product algorithm, while having lower storage memory requirements and much lower latency. We further evaluate the proposed algorithms for use in beyond 400 Gb/s serial optical transmission in combination with PolMUX 32-IPQ-based signal constellation and show that low BERs can be achieved for medium optical SNRs, while achieving the net coding gain above 11.4 dB.

Low Density Parity Check Codes: Bandwidth Efficient Channel Coding

NASA Technical Reports Server (NTRS)

Fong, Wai; Lin, Shu; Maki, Gary; Yeh, Pen-Shu

2003-01-01

Low Density Parity Check (LDPC) Codes provide near-Shannon Capacity performance for NASA Missions. These codes have high coding rates R=0.82 and 0.875 with moderate code lengths, n=4096 and 8176. Their decoders have inherently parallel structures which allows for high-speed implementation. Two codes based on Euclidean Geometry (EG) were selected for flight ASIC implementation. These codes are cyclic and quasi-cyclic in nature and therefore have a simple encoder structure. This results in power and size benefits. These codes also have a large minimum distance as much as d,,, = 65 giving them powerful error correcting capabilities and error floors less than lo- BER. This paper will present development of the LDPC flight encoder and decoder, its applications and status.

Statistical mechanics of broadcast channels using low-density parity-check codes.

PubMed

Nakamura, Kazutaka; Kabashima, Yoshiyuki; Morelos-Zaragoza, Robert; Saad, David

2003-03-01

We investigate the use of Gallager's low-density parity-check (LDPC) codes in a degraded broadcast channel, one of the fundamental models in network information theory. Combining linear codes is a standard technique in practical network communication schemes and is known to provide better performance than simple time sharing methods when algebraic codes are used. The statistical physics based analysis shows that the practical performance of the suggested method, achieved by employing the belief propagation algorithm, is superior to that of LDPC based time sharing codes while the best performance, when received transmissions are optimally decoded, is bounded by the time sharing limit.

LDPC-based iterative joint source-channel decoding for JPEG2000.

PubMed

Pu, Lingling; Wu, Zhenyu; Bilgin, Ali; Marcellin, Michael W; Vasic, Bane

2007-02-01

A framework is proposed for iterative joint source-channel decoding of JPEG2000 codestreams. At the encoder, JPEG2000 is used to perform source coding with certain error-resilience (ER) modes, and LDPC codes are used to perform channel coding. During decoding, the source decoder uses the ER modes to identify corrupt sections of the codestream and provides this information to the channel decoder. Decoding is carried out jointly in an iterative fashion. Experimental results indicate that the proposed method requires fewer iterations and improves overall system performance.

428-Gb/s single-channel coherent optical OFDM transmission over 960-km SSMF with constellation expansion and LDPC coding.

PubMed

Yang, Qi; Al Amin, Abdullah; Chen, Xi; Ma, Yiran; Chen, Simin; Shieh, William

2010-08-02

High-order modulation formats and advanced error correcting codes (ECC) are two promising techniques for improving the performance of ultrahigh-speed optical transport networks. In this paper, we present record receiver sensitivity for 107 Gb/s CO-OFDM transmission via constellation expansion to 16-QAM and rate-1/2 LDPC coding. We also show the single-channel transmission of a 428-Gb/s CO-OFDM signal over 960-km standard-single-mode-fiber (SSMF) without Raman amplification.

LDPC product coding scheme with extrinsic information for bit patterned media recoding

NASA Astrophysics Data System (ADS)

Jeong, Seongkwon; Lee, Jaejin

2017-05-01

Since the density limit of the current perpendicular magnetic storage system will soon be reached, bit patterned media recording (BPMR) is a promising candidate for the next generation storage system to achieve an areal density beyond 1 Tb/in2. Each recording bit is stored in a fabricated magnetic island and the space between the magnetic islands is nonmagnetic in BPMR. To approach recording densities of 1 Tb/in2, the spacing of the magnetic islands must be less than 25 nm. Consequently, severe inter-symbol interference (ISI) and inter-track interference (ITI) occur. ITI and ISI degrade the performance of BPMR. In this paper, we propose a low-density parity check (LDPC) product coding scheme that exploits extrinsic information for BPMR. This scheme shows an improved bit error rate performance compared to that in which one LDPC code is used.

Low Power LDPC Code Decoder Architecture Based on Intermediate Message Compression Technique

NASA Astrophysics Data System (ADS)

Shimizu, Kazunori; Togawa, Nozomu; Ikenaga, Takeshi; Goto, Satoshi

Reducing the power dissipation for LDPC code decoder is a major challenging task to apply it to the practical digital communication systems. In this paper, we propose a low power LDPC code decoder architecture based on an intermediate message-compression technique which features as follows: (i) An intermediate message compression technique enables the decoder to reduce the required memory capacity and write power dissipation. (ii) A clock gated shift register based intermediate message memory architecture enables the decoder to decompress the compressed messages in a single clock cycle while reducing the read power dissipation. The combination of the above two techniques enables the decoder to reduce the power dissipation while keeping the decoding throughput. The simulation results show that the proposed architecture improves the power efficiency up to 52% and 18% compared to that of the decoder based on the overlapped schedule and the rapid convergence schedule without the proposed techniques respectively.

45 Gb/s low complexity optical front-end for soft-decision LDPC decoders.

PubMed

Sakib, Meer Nazmus; Moayedi, Monireh; Gross, Warren J; Liboiron-Ladouceur, Odile

2012-07-30

In this paper a low complexity and energy efficient 45 Gb/s soft-decision optical front-end to be used with soft-decision low-density parity-check (LDPC) decoders is demonstrated. The results show that the optical front-end exhibits a net coding gain of 7.06 and 9.62 dB for post forward error correction bit error rate of 10(-7) and 10(-12) for long block length LDPC(32768,26803) code. The performance over a hard decision front-end is 1.9 dB for this code. It is shown that the soft-decision circuit can also be used as a 2-bit flash type analog-to-digital converter (ADC), in conjunction with equalization schemes. At bit rate of 15 Gb/s using RS(255,239), LDPC(672,336), (672, 504), (672, 588), and (1440, 1344) used with a 6-tap finite impulse response (FIR) equalizer will result in optical power savings of 3, 5, 7, 9.5 and 10.5 dB, respectively. The 2-bit flash ADC consumes only 2.71 W at 32 GSamples/s. At 45 GSamples/s the power consumption is estimated to be 4.95 W.

High-efficiency reconciliation for continuous variable quantum key distribution

NASA Astrophysics Data System (ADS)

Bai, Zengliang; Yang, Shenshen; Li, Yongmin

2017-04-01

Quantum key distribution (QKD) is the most mature application of quantum information technology. Information reconciliation is a crucial step in QKD and significantly affects the final secret key rates shared between two legitimate parties. We analyze and compare various construction methods of low-density parity-check (LDPC) codes and design high-performance irregular LDPC codes with a block length of 106. Starting from these good codes and exploiting the slice reconciliation technique based on multilevel coding and multistage decoding, we realize high-efficiency Gaussian key reconciliation with efficiency higher than 95% for signal-to-noise ratios above 1. Our demonstrated method can be readily applied in continuous variable QKD.

Memory-efficient decoding of LDPC codes

NASA Technical Reports Server (NTRS)

Kwok-San Lee, Jason; Thorpe, Jeremy; Hawkins, Jon

2005-01-01

We present a low-complexity quantization scheme for the implementation of regular (3,6) LDPC codes. The quantization parameters are optimized to maximize the mutual information between the source and the quantized messages. Using this non-uniform quantized belief propagation algorithm, we have simulated that an optimized 3-bit quantizer operates with 0.2dB implementation loss relative to a floating point decoder, and an optimized 4-bit quantizer operates less than 0.1dB quantization loss.

PMD compensation in multilevel coded-modulation schemes with coherent detection using BLAST algorithm and iterative polarization cancellation.

PubMed

Djordjevic, Ivan B; Xu, Lei; Wang, Ting

2008-09-15

We present two PMD compensation schemes suitable for use in multilevel (M>or=2) block-coded modulation schemes with coherent detection. The first scheme is based on a BLAST-type polarization-interference cancellation scheme, and the second scheme is based on iterative polarization cancellation. Both schemes use the LDPC codes as channel codes. The proposed PMD compensations schemes are evaluated by employing coded-OFDM and coherent detection. When used in combination with girth-10 LDPC codes those schemes outperform polarization-time coding based OFDM by 1 dB at BER of 10(-9), and provide two times higher spectral efficiency. The proposed schemes perform comparable and are able to compensate even 1200 ps of differential group delay with negligible penalty.

Statistical physics inspired energy-efficient coded-modulation for optical communications.

PubMed

Djordjevic, Ivan B; Xu, Lei; Wang, Ting

2012-04-15

Because Shannon's entropy can be obtained by Stirling's approximation of thermodynamics entropy, the statistical physics energy minimization methods are directly applicable to the signal constellation design. We demonstrate that statistical physics inspired energy-efficient (EE) signal constellation designs, in combination with large-girth low-density parity-check (LDPC) codes, significantly outperform conventional LDPC-coded polarization-division multiplexed quadrature amplitude modulation schemes. We also describe an EE signal constellation design algorithm. Finally, we propose the discrete-time implementation of D-dimensional transceiver and corresponding EE polarization-division multiplexed system. © 2012 Optical Society of America

Photonic entanglement-assisted quantum low-density parity-check encoders and decoders.

PubMed

Djordjevic, Ivan B

2010-05-01

I propose encoder and decoder architectures for entanglement-assisted (EA) quantum low-density parity-check (LDPC) codes suitable for all-optical implementation. I show that two basic gates needed for EA quantum error correction, namely, controlled-NOT (CNOT) and Hadamard gates can be implemented based on Mach-Zehnder interferometer. In addition, I show that EA quantum LDPC codes from balanced incomplete block designs of unitary index require only one entanglement qubit to be shared between source and destination.

On the optimum signal constellation design for high-speed optical transport networks.

PubMed

Liu, Tao; Djordjevic, Ivan B

2012-08-27

In this paper, we first describe an optimum signal constellation design algorithm, which is optimum in MMSE-sense, called MMSE-OSCD, for channel capacity achieving source distribution. Secondly, we introduce a feedback channel capacity inspired optimum signal constellation design (FCC-OSCD) to further improve the performance of MMSE-OSCD, inspired by the fact that feedback channel capacity is higher than that of systems without feedback. The constellations obtained by FCC-OSCD are, however, OSNR dependent. The optimization is jointly performed together with regular quasi-cyclic low-density parity-check (LDPC) code design. Such obtained coded-modulation scheme, in combination with polarization-multiplexing, is suitable as both 400 Gb/s and multi-Tb/s optical transport enabling technology. Using large girth LDPC code, we demonstrate by Monte Carlo simulations that a 32-ary signal constellation, obtained by FCC-OSCD, outperforms previously proposed optimized 32-ary CIPQ signal constellation by 0.8 dB at BER of 10(-7). On the other hand, the LDPC-coded 16-ary FCC-OSCD outperforms 16-QAM by 1.15 dB at the same BER.

Capacity Maximizing Constellations

NASA Technical Reports Server (NTRS)

Barsoum, Maged; Jones, Christopher

2010-01-01

Some non-traditional signal constellations have been proposed for transmission of data over the Additive White Gaussian Noise (AWGN) channel using such channel-capacity-approaching codes as low-density parity-check (LDPC) or turbo codes. Computational simulations have shown performance gains of more than 1 dB over traditional constellations. These gains could be translated to bandwidth- efficient communications, variously, over longer distances, using less power, or using smaller antennas. The proposed constellations have been used in a bit-interleaved coded modulation system employing state-ofthe-art LDPC codes. In computational simulations, these constellations were shown to afford performance gains over traditional constellations as predicted by the gap between the parallel decoding capacity of the constellations and the Gaussian capacity

Multiple component codes based generalized LDPC codes for high-speed optical transport.

PubMed

Djordjevic, Ivan B; Wang, Ting

2014-07-14

A class of generalized low-density parity-check (GLDPC) codes suitable for optical communications is proposed, which consists of multiple local codes. It is shown that Hamming, BCH, and Reed-Muller codes can be used as local codes, and that the maximum a posteriori probability (MAP) decoding of these local codes by Ashikhmin-Lytsin algorithm is feasible in terms of complexity and performance. We demonstrate that record coding gains can be obtained from properly designed GLDPC codes, derived from multiple component codes. We then show that several recently proposed classes of LDPC codes such as convolutional and spatially-coupled codes can be described using the concept of GLDPC coding, which indicates that the GLDPC coding can be used as a unified platform for advanced FEC enabling ultra-high speed optical transport. The proposed class of GLDPC codes is also suitable for code-rate adaption, to adjust the error correction strength depending on the optical channel conditions.

Maximum likelihood decoding analysis of Accumulate-Repeat-Accumulate Codes

NASA Technical Reports Server (NTRS)

Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

2004-01-01

Repeat-Accumulate (RA) codes are the simplest turbo-like codes that achieve good performance. However, they cannot compete with Turbo codes or low-density parity check codes (LDPC) as far as performance is concerned. The Accumulate Repeat Accumulate (ARA) codes, as a subclass of LDPC codes, are obtained by adding a pre-coder in front of RA codes with puncturing where an accumulator is chosen as a precoder. These codes not only are very simple, but also achieve excellent performance with iterative decoding. In this paper, the performance of these codes with (ML) decoding are analyzed and compared to random codes by very tight bounds. The weight distribution of some simple ARA codes is obtained, and through existing tightest bounds we have shown the ML SNR threshold of ARA codes approaches very closely to the performance of random codes. We have shown that the use of precoder improves the SNR threshold but interleaving gain remains unchanged with respect to RA code with puncturing.

A code-aided carrier synchronization algorithm based on improved nonbinary low-density parity-check codes

NASA Astrophysics Data System (ADS)

Bai, Cheng-lin; Cheng, Zhi-hui

2016-09-01

In order to further improve the carrier synchronization estimation range and accuracy at low signal-to-noise ratio ( SNR), this paper proposes a code-aided carrier synchronization algorithm based on improved nonbinary low-density parity-check (NB-LDPC) codes to study the polarization-division-multiplexing coherent optical orthogonal frequency division multiplexing (PDM-CO-OFDM) system performance in the cases of quadrature phase shift keying (QPSK) and 16 quadrature amplitude modulation (16-QAM) modes. The simulation results indicate that this algorithm can enlarge frequency and phase offset estimation ranges and enhance accuracy of the system greatly, and the bit error rate ( BER) performance of the system is improved effectively compared with that of the system employing traditional NB-LDPC code-aided carrier synchronization algorithm.

Performance optimization of PM-16QAM transmission system enabled by real-time self-adaptive coding.

PubMed

Qu, Zhen; Li, Yao; Mo, Weiyang; Yang, Mingwei; Zhu, Shengxiang; Kilper, Daniel C; Djordjevic, Ivan B

2017-10-15

We experimentally demonstrate self-adaptive coded 5×100  Gb/s WDM polarization multiplexed 16 quadrature amplitude modulation transmission over a 100 km fiber link, which is enabled by a real-time control plane. The real-time optical signal-to-noise ratio (OSNR) is measured using an optical performance monitoring device. The OSNR measurement is processed and fed back using control plane logic and messaging to the transmitter side for code adaptation, where the binary data are adaptively encoded with three types of low-density parity-check (LDPC) codes with code rates of 0.8, 0.75, and 0.7 of large girth. The total code-adaptation latency is measured to be 2273 ms. Compared with transmission without adaptation, average net capacity improvements of 102%, 36%, and 7.5% are obtained, respectively, by adaptive LDPC coding.

Performance analysis of LDPC codes on OOK terahertz wireless channels

NASA Astrophysics Data System (ADS)

Chun, Liu; Chang, Wang; Jun-Cheng, Cao

2016-02-01

Atmospheric absorption, scattering, and scintillation are the major causes to deteriorate the transmission quality of terahertz (THz) wireless communications. An error control coding scheme based on low density parity check (LDPC) codes with soft decision decoding algorithm is proposed to improve the bit-error-rate (BER) performance of an on-off keying (OOK) modulated THz signal through atmospheric channel. The THz wave propagation characteristics and channel model in atmosphere is set up. Numerical simulations validate the great performance of LDPC codes against the atmospheric fading and demonstrate the huge potential in future ultra-high speed beyond Gbps THz communications. Project supported by the National Key Basic Research Program of China (Grant No. 2014CB339803), the National High Technology Research and Development Program of China (Grant No. 2011AA010205), the National Natural Science Foundation of China (Grant Nos. 61131006, 61321492, and 61204135), the Major National Development Project of Scientific Instrument and Equipment (Grant No. 2011YQ150021), the National Science and Technology Major Project (Grant No. 2011ZX02707), the International Collaboration and Innovation Program on High Mobility Materials Engineering of the Chinese Academy of Sciences, and the Shanghai Municipal Commission of Science and Technology (Grant No. 14530711300).

Comparison of soft-input-soft-output detection methods for dual-polarized quadrature duobinary system

NASA Astrophysics Data System (ADS)

Chang, Chun; Huang, Benxiong; Xu, Zhengguang; Li, Bin; Zhao, Nan

2018-02-01

Three soft-input-soft-output (SISO) detection methods for dual-polarized quadrature duobinary (DP-QDB), including maximum-logarithmic-maximum-a-posteriori-probability-algorithm (Max-log-MAP)-based detection, soft-output-Viterbi-algorithm (SOVA)-based detection, and a proposed SISO detection, which can all be combined with SISO decoding, are presented. The three detection methods are investigated at 128 Gb/s in five-channel wavelength-division-multiplexing uncoded and low-density-parity-check (LDPC) coded DP-QDB systems by simulations. Max-log-MAP-based detection needs the returning-to-initial-states (RTIS) process despite having the best performance. When the LDPC code with a code rate of 0.83 is used, the detecting-and-decoding scheme with the SISO detection does not need RTIS and has better bit error rate (BER) performance than the scheme with SOVA-based detection. The former can reduce the optical signal-to-noise ratio (OSNR) requirement (at BER=10-5) by 2.56 dB relative to the latter. The application of the SISO iterative detection in LDPC-coded DP-QDB systems makes a good trade-off between requirements on transmission efficiency, OSNR requirement, and transmission distance, compared with the other two SISO methods.

FPGA implementation of advanced FEC schemes for intelligent aggregation networks

NASA Astrophysics Data System (ADS)

Zou, Ding; Djordjevic, Ivan B.

2016-02-01

In state-of-the-art fiber-optics communication systems the fixed forward error correction (FEC) and constellation size are employed. While it is important to closely approach the Shannon limit by using turbo product codes (TPC) and low-density parity-check (LDPC) codes with soft-decision decoding (SDD) algorithm; rate-adaptive techniques, which enable increased information rates over short links and reliable transmission over long links, are likely to become more important with ever-increasing network traffic demands. In this invited paper, we describe a rate adaptive non-binary LDPC coding technique, and demonstrate its flexibility and good performance exhibiting no error floor at BER down to 10-15 in entire code rate range, by FPGA-based emulation, making it a viable solution in the next-generation high-speed intelligent aggregation networks.

Information-reduced Carrier Synchronization of Iterative Decoded BPSK and QPSK using Soft Decision (Extrinsic) Feedback

NASA Technical Reports Server (NTRS)

Simon, Marvin; Valles, Esteban; Jones, Christopher

2008-01-01

This paper addresses the carrier-phase estimation problem under low SNR conditions as are typical of turbo- and LDPC-coded applications. In previous publications by the first author, closed-loop carrier synchronization schemes for error-correction coded BPSK and QPSK modulation were proposed that were based on feeding back hard data decisions at the input of the loop, the purpose being to remove the modulation prior to attempting to track the carrier phase as opposed to the more conventional decision-feedback schemes that incorporate such feedback inside the loop. In this paper, we consider an alternative approach wherein the extrinsic soft information from the iterative decoder of turbo or LDPC codes is instead used as the feedback.

Efficacy analysis of LDPC coded APSK modulated differential space-time-frequency coded for wireless body area network using MB-pulsed OFDM UWB technology.

PubMed

Manimegalai, C T; Gauni, Sabitha; Kalimuthu, K

2017-12-04

Wireless body area network (WBAN) is a breakthrough technology in healthcare areas such as hospital and telemedicine. The human body has a complex mixture of different tissues. It is expected that the nature of propagation of electromagnetic signals is distinct in each of these tissues. This forms the base for the WBAN, which is different from other environments. In this paper, the knowledge of Ultra Wide Band (UWB) channel is explored in the WBAN (IEEE 802.15.6) system. The measurements of parameters in frequency range from 3.1-10.6 GHz are taken. The proposed system, transmits data up to 480 Mbps by using LDPC coded APSK Modulated Differential Space-Time-Frequency Coded MB-OFDM to increase the throughput and power efficiency.

An LDPC Decoder Architecture for Wireless Sensor Network Applications

PubMed Central

Giancarlo Biroli, Andrea Dario; Martina, Maurizio; Masera, Guido

2012-01-01

The pervasive use of wireless sensors in a growing spectrum of human activities reinforces the need for devices with low energy dissipation. In this work, coded communication between a couple of wireless sensor devices is considered as a method to reduce the dissipated energy per transmitted bit with respect to uncoded communication. Different Low Density Parity Check (LDPC) codes are considered to this purpose and post layout results are shown for a low-area low-energy decoder, which offers percentage energy savings with respect to the uncoded solution in the range of 40%–80%, depending on considered environment, distance and bit error rate. PMID:22438724

An LDPC decoder architecture for wireless sensor network applications.

PubMed

Biroli, Andrea Dario Giancarlo; Martina, Maurizio; Masera, Guido

2012-01-01

The pervasive use of wireless sensors in a growing spectrum of human activities reinforces the need for devices with low energy dissipation. In this work, coded communication between a couple of wireless sensor devices is considered as a method to reduce the dissipated energy per transmitted bit with respect to uncoded communication. Different Low Density Parity Check (LDPC) codes are considered to this purpose and post layout results are shown for a low-area low-energy decoder, which offers percentage energy savings with respect to the uncoded solution in the range of 40%-80%, depending on considered environment, distance and bit error rate.

Rate-Compatible LDPC Codes with Linear Minimum Distance

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Jones, Christopher; Dolinar, Samuel

2009-01-01

A recently developed method of constructing protograph-based low-density parity-check (LDPC) codes provides for low iterative decoding thresholds and minimum distances proportional to block sizes, and can be used for various code rates. A code constructed by this method can have either fixed input block size or fixed output block size and, in either case, provides rate compatibility. The method comprises two submethods: one for fixed input block size and one for fixed output block size. The first mentioned submethod is useful for applications in which there are requirements for rate-compatible codes that have fixed input block sizes. These are codes in which only the numbers of parity bits are allowed to vary. The fixed-output-blocksize submethod is useful for applications in which framing constraints are imposed on the physical layers of affected communication systems. An example of such a system is one that conforms to one of many new wireless-communication standards that involve the use of orthogonal frequency-division modulation

Adaptive software-defined coded modulation for ultra-high-speed optical transport

NASA Astrophysics Data System (ADS)

Djordjevic, Ivan B.; Zhang, Yequn

2013-10-01

In optically-routed networks, different wavelength channels carrying the traffic to different destinations can have quite different optical signal-to-noise ratios (OSNRs) and signal is differently impacted by various channel impairments. Regardless of the data destination, an optical transport system (OTS) must provide the target bit-error rate (BER) performance. To provide target BER regardless of the data destination we adjust the forward error correction (FEC) strength. Depending on the information obtained from the monitoring channels, we select the appropriate code rate matching to the OSNR range that current channel OSNR falls into. To avoid frame synchronization issues, we keep the codeword length fixed independent of the FEC code being employed. The common denominator is the employment of quasi-cyclic (QC-) LDPC codes in FEC. For high-speed implementation, low-complexity LDPC decoding algorithms are needed, and some of them will be described in this invited paper. Instead of conventional QAM based modulation schemes, we employ the signal constellations obtained by optimum signal constellation design (OSCD) algorithm. To improve the spectral efficiency, we perform the simultaneous rate adaptation and signal constellation size selection so that the product of number of bits per symbol × code rate is closest to the channel capacity. Further, we describe the advantages of using 4D signaling instead of polarization-division multiplexed (PDM) QAM, by using the 4D MAP detection, combined with LDPC coding, in a turbo equalization fashion. Finally, to solve the problems related to the limited bandwidth of information infrastructure, high energy consumption, and heterogeneity of optical networks, we describe an adaptive energy-efficient hybrid coded-modulation scheme, which in addition to amplitude, phase, and polarization state employs the spatial modes as additional basis functions for multidimensional coded-modulation.

Uplink Coding

NASA Technical Reports Server (NTRS)

Andrews, Ken; Divsalar, Dariush; Dolinar, Sam; Moision, Bruce; Hamkins, Jon; Pollara, Fabrizio

2007-01-01

This slide presentation reviews the objectives, meeting goals and overall NASA goals for the NASA Data Standards Working Group. The presentation includes information on the technical progress surrounding the objective, short LDPC codes, and the general results on the Pu-Pw tradeoff.

Two-stage cross-talk mitigation in an orbital-angular-momentum-based free-space optical communication system.

PubMed

Qu, Zhen; Djordjevic, Ivan B

2017-08-15

We propose and experimentally demonstrate a two-stage cross-talk mitigation method in an orbital-angular-momentum (OAM)-based free-space optical communication system, which is enabled by combining spatial offset and low-density parity-check (LDPC) coded nonuniform signaling. Different from traditional OAM multiplexing, where the OAM modes are centrally aligned for copropagation, the adjacent OAM modes (OAM states 2 and -6 and OAM states -2 and 6) in our proposed scheme are spatially offset to mitigate the mode cross talk. Different from traditional rectangular modulation formats, which transmit equidistant signal points with uniform probability, the 5-quadrature amplitude modulation (5-QAM) and 9-QAM are introduced to relieve cross-talk-induced performance degradation. The 5-QAM and 9-QAM formats are based on the Huffman coding technique, which can potentially achieve great cross-talk tolerance by combining them with corresponding nonbinary LDPC codes. We demonstrate that cross talk can be reduced by 1.6 dB and 1 dB via spatial offset for OAM states ±2 and ±6, respectively. Compared to quadrature phase shift keying and 8-QAM formats, the LDPC-coded 5-QAM and 9-QAM are able to bring 1.1 dB and 5.4 dB performance improvements in the presence of atmospheric turbulence, respectively.

An Efficient Downlink Scheduling Strategy Using Normal Graphs for Multiuser MIMO Wireless Systems

NASA Astrophysics Data System (ADS)

Chen, Jung-Chieh; Wu, Cheng-Hsuan; Lee, Yao-Nan; Wen, Chao-Kai

Inspired by the success of the low-density parity-check (LDPC) codes in the field of error-control coding, in this paper we propose transforming the downlink multiuser multiple-input multiple-output scheduling problem into an LDPC-like problem using the normal graph. Based on the normal graph framework, soft information, which indicates the probability that each user will be scheduled to transmit packets at the access point through a specified angle-frequency sub-channel, is exchanged among the local processors to iteratively optimize the multiuser transmission schedule. Computer simulations show that the proposed algorithm can efficiently schedule simultaneous multiuser transmission which then increases the overall channel utilization and reduces the average packet delay.

A novel decoding algorithm based on the hierarchical reliable strategy for SCG-LDPC codes in optical communications

NASA Astrophysics Data System (ADS)

Yuan, Jian-guo; Tong, Qing-zhen; Huang, Sheng; Wang, Yong

2013-11-01

An effective hierarchical reliable belief propagation (HRBP) decoding algorithm is proposed according to the structural characteristics of systematically constructed Gallager low-density parity-check (SCG-LDPC) codes. The novel decoding algorithm combines the layered iteration with the reliability judgment, and can greatly reduce the number of the variable nodes involved in the subsequent iteration process and accelerate the convergence rate. The result of simulation for SCG-LDPC(3969,3720) code shows that the novel HRBP decoding algorithm can greatly reduce the computing amount at the condition of ensuring the performance compared with the traditional belief propagation (BP) algorithm. The bit error rate (BER) of the HRBP algorithm is considerable at the threshold value of 15, but in the subsequent iteration process, the number of the variable nodes for the HRBP algorithm can be reduced by about 70% at the high signal-to-noise ratio (SNR) compared with the BP algorithm. When the threshold value is further increased, the HRBP algorithm will gradually degenerate into the layered-BP algorithm, but at the BER of 10-7 and the maximal iteration number of 30, the net coding gain (NCG) of the HRBP algorithm is 0.2 dB more than that of the BP algorithm, and the average iteration times can be reduced by about 40% at the high SNR. Therefore, the novel HRBP decoding algorithm is more suitable for optical communication systems.

Adaptive transmission based on multi-relay selection and rate-compatible LDPC codes

NASA Astrophysics Data System (ADS)

Su, Hualing; He, Yucheng; Zhou, Lin

2017-08-01

In order to adapt to the dynamical changeable channel condition and improve the transmissive reliability of the system, a cooperation system of rate-compatible low density parity check (RC-LDPC) codes combining with multi-relay selection protocol is proposed. In traditional relay selection protocol, only the channel state information (CSI) of source-relay and the CSI of relay-destination has been considered. The multi-relay selection protocol proposed by this paper takes the CSI between relays into extra account in order to obtain more chances of collabration. Additionally, the idea of hybrid automatic request retransmission (HARQ) and rate-compatible are introduced. Simulation results show that the transmissive reliability of the system can be significantly improved by the proposed protocol.

Optimal signal constellation design for ultra-high-speed optical transport in the presence of nonlinear phase noise.

PubMed

Liu, Tao; Djordjevic, Ivan B

2014-12-29

In this paper, we first describe an optimal signal constellation design algorithm suitable for the coherent optical channels dominated by the linear phase noise. Then, we modify this algorithm to be suitable for the nonlinear phase noise dominated channels. In optimization procedure, the proposed algorithm uses the cumulative log-likelihood function instead of the Euclidian distance. Further, an LDPC coded modulation scheme is proposed to be used in combination with signal constellations obtained by proposed algorithm. Monte Carlo simulations indicate that the LDPC-coded modulation schemes employing the new constellation sets, obtained by our new signal constellation design algorithm, outperform corresponding QAM constellations significantly in terms of transmission distance and have better nonlinearity tolerance.

Secret information reconciliation based on punctured low-density parity-check codes for continuous-variable quantum key distribution

NASA Astrophysics Data System (ADS)

Jiang, Xue-Qin; Huang, Peng; Huang, Duan; Lin, Dakai; Zeng, Guihua

2017-02-01

Achieving information theoretic security with practical complexity is of great interest to continuous-variable quantum key distribution in the postprocessing procedure. In this paper, we propose a reconciliation scheme based on the punctured low-density parity-check (LDPC) codes. Compared to the well-known multidimensional reconciliation scheme, the present scheme has lower time complexity. Especially when the chosen punctured LDPC code achieves the Shannon capacity, the proposed reconciliation scheme can remove the information that has been leaked to an eavesdropper in the quantum transmission phase. Therefore, there is no information leaked to the eavesdropper after the reconciliation stage. This indicates that the privacy amplification algorithm of the postprocessing procedure is no more needed after the reconciliation process. These features lead to a higher secret key rate, optimal performance, and availability for the involved quantum key distribution scheme.

Nonlinear Demodulation and Channel Coding in EBPSK Scheme

PubMed Central

Chen, Xianqing; Wu, Lenan

2012-01-01

The extended binary phase shift keying (EBPSK) is an efficient modulation technique, and a special impacting filter (SIF) is used in its demodulator to improve the bit error rate (BER) performance. However, the conventional threshold decision cannot achieve the optimum performance, and the SIF brings more difficulty in obtaining the posterior probability for LDPC decoding. In this paper, we concentrate not only on reducing the BER of demodulation, but also on providing accurate posterior probability estimates (PPEs). A new approach for the nonlinear demodulation based on the support vector machine (SVM) classifier is introduced. The SVM method which selects only a few sampling points from the filter output was used for getting PPEs. The simulation results show that the accurate posterior probability can be obtained with this method and the BER performance can be improved significantly by applying LDPC codes. Moreover, we analyzed the effect of getting the posterior probability with different methods and different sampling rates. We show that there are more advantages of the SVM method under bad condition and it is less sensitive to the sampling rate than other methods. Thus, SVM is an effective method for EBPSK demodulation and getting posterior probability for LDPC decoding. PMID:23213281

Nonlinear demodulation and channel coding in EBPSK scheme.

PubMed

Chen, Xianqing; Wu, Lenan

2012-01-01

The extended binary phase shift keying (EBPSK) is an efficient modulation technique, and a special impacting filter (SIF) is used in its demodulator to improve the bit error rate (BER) performance. However, the conventional threshold decision cannot achieve the optimum performance, and the SIF brings more difficulty in obtaining the posterior probability for LDPC decoding. In this paper, we concentrate not only on reducing the BER of demodulation, but also on providing accurate posterior probability estimates (PPEs). A new approach for the nonlinear demodulation based on the support vector machine (SVM) classifier is introduced. The SVM method which selects only a few sampling points from the filter output was used for getting PPEs. The simulation results show that the accurate posterior probability can be obtained with this method and the BER performance can be improved significantly by applying LDPC codes. Moreover, we analyzed the effect of getting the posterior probability with different methods and different sampling rates. We show that there are more advantages of the SVM method under bad condition and it is less sensitive to the sampling rate than other methods. Thus, SVM is an effective method for EBPSK demodulation and getting posterior probability for LDPC decoding.

Accumulate Repeat Accumulate Coded Modulation

NASA Technical Reports Server (NTRS)

Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

2004-01-01

In this paper we propose an innovative coded modulation scheme called 'Accumulate Repeat Accumulate Coded Modulation' (ARA coded modulation). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes that are combined with high level modulation. Thus at the decoder belief propagation can be used for iterative decoding of ARA coded modulation on a graph, provided a demapper transforms the received in-phase and quadrature samples to reliability of the bits.

Two-terminal video coding.

PubMed

Yang, Yang; Stanković, Vladimir; Xiong, Zixiang; Zhao, Wei

2009-03-01

Following recent works on the rate region of the quadratic Gaussian two-terminal source coding problem and limit-approaching code designs, this paper examines multiterminal source coding of two correlated, i.e., stereo, video sequences to save the sum rate over independent coding of both sequences. Two multiterminal video coding schemes are proposed. In the first scheme, the left sequence of the stereo pair is coded by H.264/AVC and used at the joint decoder to facilitate Wyner-Ziv coding of the right video sequence. The first I-frame of the right sequence is successively coded by H.264/AVC Intracoding and Wyner-Ziv coding. An efficient stereo matching algorithm based on loopy belief propagation is then adopted at the decoder to produce pixel-level disparity maps between the corresponding frames of the two decoded video sequences on the fly. Based on the disparity maps, side information for both motion vectors and motion-compensated residual frames of the right sequence are generated at the decoder before Wyner-Ziv encoding. In the second scheme, source splitting is employed on top of classic and Wyner-Ziv coding for compression of both I-frames to allow flexible rate allocation between the two sequences. Experiments with both schemes on stereo video sequences using H.264/AVC, LDPC codes for Slepian-Wolf coding of the motion vectors, and scalar quantization in conjunction with LDPC codes for Wyner-Ziv coding of the residual coefficients give a slightly lower sum rate than separate H.264/AVC coding of both sequences at the same video quality.

Joint Schemes for Physical Layer Security and Error Correction

ERIC Educational Resources Information Center

Adamo, Oluwayomi

2011-01-01

The major challenges facing resource constraint wireless devices are error resilience, security and speed. Three joint schemes are presented in this research which could be broadly divided into error correction based and cipher based. The error correction based ciphers take advantage of the properties of LDPC codes and Nordstrom Robinson code. A…

Encoders for block-circulant LDPC codes

NASA Technical Reports Server (NTRS)

Divsalar, Dariush (Inventor); Abbasfar, Aliazam (Inventor); Jones, Christopher R. (Inventor); Dolinar, Samuel J. (Inventor); Thorpe, Jeremy C. (Inventor); Andrews, Kenneth S. (Inventor); Yao, Kung (Inventor)

2009-01-01

Methods and apparatus to encode message input symbols in accordance with an accumulate-repeat-accumulate code with repetition three or four are disclosed. Block circulant matrices are used. A first method and apparatus make use of the block-circulant structure of the parity check matrix. A second method and apparatus use block-circulant generator matrices.

Information rates of probabilistically shaped coded modulation for a multi-span fiber-optic communication system with 64QAM

NASA Astrophysics Data System (ADS)

Fehenberger, Tobias

2018-02-01

This paper studies probabilistic shaping in a multi-span wavelength-division multiplexing optical fiber system with 64-ary quadrature amplitude modulation (QAM) input. In split-step fiber simulations and via an enhanced Gaussian noise model, three figures of merit are investigated, which are signal-to-noise ratio (SNR), achievable information rate (AIR) for capacity-achieving forward error correction (FEC) with bit-metric decoding, and the information rate achieved with low-density parity-check (LDPC) FEC. For the considered system parameters and different shaped input distributions, shaping is found to decrease the SNR by 0.3 dB yet simultaneously increases the AIR by up to 0.4 bit per 4D-symbol. The information rates of LDPC-coded modulation with shaped 64QAM input are improved by up to 0.74 bit per 4D-symbol, which is larger than the shaping gain when considering AIRs. This increase is attributed to the reduced coding gap of the higher-rate code that is used for decoding the nonuniform QAM input.

High performance reconciliation for continuous-variable quantum key distribution with LDPC code

NASA Astrophysics Data System (ADS)

Lin, Dakai; Huang, Duan; Huang, Peng; Peng, Jinye; Zeng, Guihua

2015-03-01

Reconciliation is a significant procedure in a continuous-variable quantum key distribution (CV-QKD) system. It is employed to extract secure secret key from the resulted string through quantum channel between two users. However, the efficiency and the speed of previous reconciliation algorithms are low. These problems limit the secure communication distance and the secure key rate of CV-QKD systems. In this paper, we proposed a high-speed reconciliation algorithm through employing a well-structured decoding scheme based on low density parity-check (LDPC) code. The complexity of the proposed algorithm is reduced obviously. By using a graphics processing unit (GPU) device, our method may reach a reconciliation speed of 25 Mb/s for a CV-QKD system, which is currently the highest level and paves the way to high-speed CV-QKD.

Design and performance investigation of LDPC-coded upstream transmission systems in IM/DD OFDM-PONs

NASA Astrophysics Data System (ADS)

Gong, Xiaoxue; Guo, Lei; Wu, Jingjing; Ning, Zhaolong

2016-12-01

In Intensity-Modulation Direct-Detection (IM/DD) Orthogonal Frequency Division Multiplexing Passive Optical Networks (OFDM-PONs), aside from Subcarrier-to-Subcarrier Intermixing Interferences (SSII) induced by square-law detection, the same laser frequency for data sending from Optical Network Units (ONUs) results in ONU-to-ONU Beating Interferences (OOBI) at the receiver. To mitigate those interferences, we design a Low-Density Parity Check (LDPC)-coded and spectrum-efficient upstream transmission system. A theoretical channel model is also derived, in order to analyze the detrimental factors influencing system performances. Simulation results demonstrate that the receiver sensitivity is improved 3.4 dB and 2.5 dB under QPSK and 8QAM, respectively, after 100 km Standard Single-Mode Fiber (SSMF) transmission. Furthermore, the spectrum efficiency can be improved by about 50%.

MIMO-OFDM System's Performance Using LDPC Codes for a Mobile Robot

NASA Astrophysics Data System (ADS)

Daoud, Omar; Alani, Omar

This work deals with the performance of a Sniffer Mobile Robot (SNFRbot)-based spatial multiplexed wireless Orthogonal Frequency Division Multiplexing (OFDM) transmission technology. The use of Multi-Input Multi-Output (MIMO)-OFDM technology increases the wireless transmission rate without increasing transmission power or bandwidth. A generic multilayer architecture of the SNFRbot is proposed with low power and low cost. Some experimental results are presented and show the efficiency of sniffing deadly gazes, sensing high temperatures and sending live videos of the monitored situation. Moreover, simulation results show the achieved performance by tackling the Peak-to-Average Power Ratio (PAPR) problem of the used technology using Low Density Parity Check (LDPC) codes; and the effect of combating the PAPR on the bit error rate (BER) and the signal to noise ratio (SNR) over a Doppler spread channel.

Performance of Low-Density Parity-Check Coded Modulation

NASA Astrophysics Data System (ADS)

Hamkins, J.

2011-02-01

This article presents the simulated performance of a family of nine AR4JA low-density parity-check (LDPC) codes when used with each of five modulations. In each case, the decoder inputs are codebit log-likelihood ratios computed from the received (noisy) modulation symbols using a general formula which applies to arbitrary modulations. Suboptimal soft-decision and hard-decision demodulators are also explored. Bit-interleaving and various mappings of bits to modulation symbols are considered. A number of subtle decoder algorithm details are shown to affect performance, especially in the error floor region. Among these are quantization dynamic range and step size, clipping degree-one variable nodes, "Jones clipping" of variable nodes, approximations of the min* function, and partial hard-limiting messages from check nodes. Using these decoder optimizations, all coded modulations simulated here are free of error floors down to codeword error rates below 10^{-6}. The purpose of generating this performance data is to aid system engineers in determining an appropriate code and modulation to use under specific power and bandwidth constraints, and to provide information needed to design a variable/adaptive coded modulation (VCM/ACM) system using the AR4JA codes. IPNPR Volume 42-185 Tagged File.txt

A new LDPC decoding scheme for PDM-8QAM BICM coherent optical communication system

NASA Astrophysics Data System (ADS)

Liu, Yi; Zhang, Wen-bo; Xi, Li-xia; Tang, Xian-feng; Zhang, Xiao-guang

2015-11-01

A new log-likelihood ratio (LLR) message estimation method is proposed for polarization-division multiplexing eight quadrature amplitude modulation (PDM-8QAM) bit-interleaved coded modulation (BICM) optical communication system. The formulation of the posterior probability is theoretically analyzed, and the way to reduce the pre-decoding bit error rate ( BER) of the low density parity check (LDPC) decoder for PDM-8QAM constellations is presented. Simulation results show that it outperforms the traditional scheme, i.e., the new post-decoding BER is decreased down to 50% of that of the traditional post-decoding algorithm.

Fixed-point Design of the Lattice-reduction-aided Iterative Detection and Decoding Receiver for Coded MIMO Systems

DTIC Science & Technology

2011-01-01

reliability, e.g., Turbo Codes [2] and Low Density Parity Check ( LDPC ) codes [3]. The challenge to apply both MIMO and ECC into wireless systems is on...REPORT Fixed-point Design of theLattice-reduction-aided Iterative Detection andDecoding Receiver for Coded MIMO Systems 14. ABSTRACT 16. SECURITY...illustrates the performance of coded LR aided detectors. 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY NOTES The views, opinions

A Low-Complexity and High-Performance 2D Look-Up Table for LDPC Hardware Implementation

NASA Astrophysics Data System (ADS)

Chen, Jung-Chieh; Yang, Po-Hui; Lain, Jenn-Kaie; Chung, Tzu-Wen

In this paper, we propose a low-complexity, high-efficiency two-dimensional look-up table (2D LUT) for carrying out the sum-product algorithm in the decoding of low-density parity-check (LDPC) codes. Instead of employing adders for the core operation when updating check node messages, in the proposed scheme, the main term and correction factor of the core operation are successfully merged into a compact 2D LUT. Simulation results indicate that the proposed 2D LUT not only attains close-to-optimal bit error rate performance but also enjoys a low complexity advantage that is suitable for hardware implementation.

Measurement Techniques for Clock Jitter

NASA Technical Reports Server (NTRS)

Lansdowne, Chatwin; Schlesinger, Adam

2012-01-01

NASA is in the process of modernizing its communications infrastructure to accompany the development of a Crew Exploration Vehicle (CEV) to replace the shuttle. With this effort comes the opportunity to infuse more advanced coded modulation techniques, including low-density parity-check (LDPC) codes that offer greater coding gains than the current capability. However, in order to take full advantage of these codes, the ground segment receiver synchronization loops must be able to operate at a lower signal-to-noise ratio (SNR) than supported by equipment currently in use.

Landsat Data Continuity Mission (LDCM) - Optimizing X-Band Usage

NASA Technical Reports Server (NTRS)

Garon, H. M.; Gal-Edd, J. S.; Dearth, K. W.; Sank, V. I.

2010-01-01

The NASA version of the low-density parity check (LDPC) 7/8-rate code, shortened to the dimensions of (8160, 7136), has been implemented as the forward error correction (FEC) schema for the Landsat Data Continuity Mission (LDCM). This is the first flight application of this code. In order to place a 440 Msps link within the 375 MHz wide X band we found it necessary to heavily bandpass filter the satellite transmitter output . Despite the significant amplitude and phase distortions that accompanied the spectral truncation, the mission required BER is maintained at < 10(exp -12) with less than 2 dB of implementation loss. We utilized a band-pass filter designed ostensibly to replicate the link distortions to demonstrate link design viability. The same filter was then used to optimize the adaptive equalizer in the receiver employed at the terminus of the downlink. The excellent results we obtained could be directly attributed to the implementation of the LDPC code and the amplitude and phase compensation provided in the receiver. Similar results were obtained with receivers from several vendors.

Quantum Kronecker sum-product low-density parity-check codes with finite rate

NASA Astrophysics Data System (ADS)

Kovalev, Alexey A.; Pryadko, Leonid P.

2013-07-01

We introduce an ansatz for quantum codes which gives the hypergraph-product (generalized toric) codes by Tillich and Zémor and generalized bicycle codes by MacKay as limiting cases. The construction allows for both the lower and the upper bounds on the minimum distance; they scale as a square root of the block length. Many thus defined codes have a finite rate and limited-weight stabilizer generators, an analog of classical low-density parity-check (LDPC) codes. Compared to the hypergraph-product codes, hyperbicycle codes generally have a wider range of parameters; in particular, they can have a higher rate while preserving the estimated error threshold.

Accumulate-Repeat-Accumulate-Accumulate Codes

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Dolinar, Samuel; Thorpe, Jeremy

2007-01-01

Accumulate-repeat-accumulate-accumulate (ARAA) codes have been proposed, inspired by the recently proposed accumulate-repeat-accumulate (ARA) codes. These are error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels. ARAA codes can be regarded as serial turbolike codes or as a subclass of low-density parity-check (LDPC) codes, and, like ARA codes they have projected graph or protograph representations; these characteristics make it possible to design high-speed iterative decoders that utilize belief-propagation algorithms. The objective in proposing ARAA codes as a subclass of ARA codes was to enhance the error-floor performance of ARA codes while maintaining simple encoding structures and low maximum variable node degree.

A Simulation Testbed for Adaptive Modulation and Coding in Airborne Telemetry (Brief)

DTIC Science & Technology

2014-10-01

SOQPSK 0.0085924 us 0.015231 kH2 10 1/2 20 Time Modulation/ Coding State ... .. . . D - 2/3 3/4 4/5 GTRI_B-‹#› MATLAB GUI Interface 8...802.11a) • Modulations: BPSK, QPSK, 16 QAM, 64 QAM • Cyclic Prefix Lengths • Number of Subcarriers • Coding • LDPC • Rates: 1/2, 2/3, 3/4, 4/5...and Coding in Airborne Telemetry (Brief) October 2014 DISTRIBUTION STATEMENT A. Approved for public release: distribution unlimited. Test

500  Gb/s free-space optical transmission over strong atmospheric turbulence channels.

PubMed

Qu, Zhen; Djordjevic, Ivan B

2016-07-15

We experimentally demonstrate a high-spectral-efficiency, large-capacity, featured free-space-optical (FSO) transmission system by using low-density, parity-check (LDPC) coded quadrature phase shift keying (QPSK) combined with orbital angular momentum (OAM) multiplexing. The strong atmospheric turbulence channel is emulated by two spatial light modulators on which four randomly generated azimuthal phase patterns yielding the Andrews spectrum are recorded. The validity of such an approach is verified by reproducing the intensity distribution and irradiance correlation function (ICF) from the full-scale simulator. Excellent agreement of experimental, numerical, and analytical results is found. To reduce the phase distortion induced by the turbulence emulator, the inexpensive wavefront sensorless adaptive optics (AO) is used. To deal with remaining channel impairments, a large-girth LDPC code is used. To further improve the aggregate data rate, the OAM multiplexing is combined with WDM, and 500 Gb/s optical transmission over the strong atmospheric turbulence channels is demonstrated.

A Novel Strategy Using Factor Graphs and the Sum-Product Algorithm for Satellite Broadcast Scheduling Problems

NASA Astrophysics Data System (ADS)

Chen, Jung-Chieh

This paper presents a low complexity algorithmic framework for finding a broadcasting schedule in a low-altitude satellite system, i. e., the satellite broadcast scheduling (SBS) problem, based on the recent modeling and computational methodology of factor graphs. Inspired by the huge success of the low density parity check (LDPC) codes in the field of error control coding, in this paper, we transform the SBS problem into an LDPC-like problem through a factor graph instead of using the conventional neural network approaches to solve the SBS problem. Based on a factor graph framework, the soft-information, describing the probability that each satellite will broadcast information to a terminal at a specific time slot, is exchanged among the local processing in the proposed framework via the sum-product algorithm to iteratively optimize the satellite broadcasting schedule. Numerical results show that the proposed approach not only can obtain optimal solution but also enjoys the low complexity suitable for integral-circuit implementation.

Optimum Boundaries of Signal-to-Noise Ratio for Adaptive Code Modulations

DTIC Science & Technology

2017-11-14

1510–1521, Feb. 2015. [2]. Pursley, M. B. and Royster, T. C., “Adaptive-rate nonbinary LDPC coding for frequency - hop communications ,” IEEE...and this can cause a very narrowband noise near the center frequency during USRP signal acquisition and generation. This can cause a high BER...Final Report APPROVED FOR PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED. AIR FORCE RESEARCH LABORATORY Space Vehicles Directorate 3550 Aberdeen Ave

Research on Formation of Microsatellite Communication with Genetic Algorithm

PubMed Central

Wu, Guoqiang; Bai, Yuguang; Sun, Zhaowei

2013-01-01

For the formation of three microsatellites which fly in the same orbit and perform three-dimensional solid mapping for terra, this paper proposes an optimizing design method of space circular formation order based on improved generic algorithm and provides an intersatellite direct spread spectrum communication system. The calculating equation of LEO formation flying satellite intersatellite links is guided by the special requirements of formation-flying microsatellite intersatellite links, and the transmitter power is also confirmed throughout the simulation. The method of space circular formation order optimizing design based on improved generic algorithm is given, and it can keep formation order steady for a long time under various absorb impetus. The intersatellite direct spread spectrum communication system is also provided. It can be found that, when the distance is 1 km and the data rate is 1 Mbps, the input wave matches preferably with the output wave. And LDPC code can improve the communication performance. The correct capability of (512, 256) LDPC code is better than (2, 1, 7) convolution code, distinctively. The design system can satisfy the communication requirements of microsatellites. So, the presented method provides a significant theory foundation for formation-flying and intersatellite communication. PMID:24078796

Research on formation of microsatellite communication with genetic algorithm.

PubMed

Wu, Guoqiang; Bai, Yuguang; Sun, Zhaowei

2013-01-01

For the formation of three microsatellites which fly in the same orbit and perform three-dimensional solid mapping for terra, this paper proposes an optimizing design method of space circular formation order based on improved generic algorithm and provides an intersatellite direct spread spectrum communication system. The calculating equation of LEO formation flying satellite intersatellite links is guided by the special requirements of formation-flying microsatellite intersatellite links, and the transmitter power is also confirmed throughout the simulation. The method of space circular formation order optimizing design based on improved generic algorithm is given, and it can keep formation order steady for a long time under various absorb impetus. The intersatellite direct spread spectrum communication system is also provided. It can be found that, when the distance is 1 km and the data rate is 1 Mbps, the input wave matches preferably with the output wave. And LDPC code can improve the communication performance. The correct capability of (512, 256) LDPC code is better than (2, 1, 7) convolution code, distinctively. The design system can satisfy the communication requirements of microsatellites. So, the presented method provides a significant theory foundation for formation-flying and intersatellite communication.

LDPC decoder with a limited-precision FPGA-based floating-point multiplication coprocessor

NASA Astrophysics Data System (ADS)

Moberly, Raymond; O'Sullivan, Michael; Waheed, Khurram

2007-09-01

Implementing the sum-product algorithm, in an FPGA with an embedded processor, invites us to consider a tradeoff between computational precision and computational speed. The algorithm, known outside of the signal processing community as Pearl's belief propagation, is used for iterative soft-decision decoding of LDPC codes. We determined the feasibility of a coprocessor that will perform product computations. Our FPGA-based coprocessor (design) performs computer algebra with significantly less precision than the standard (e.g. integer, floating-point) operations of general purpose processors. Using synthesis, targeting a 3,168 LUT Xilinx FPGA, we show that key components of a decoder are feasible and that the full single-precision decoder could be constructed using a larger part. Soft-decision decoding by the iterative belief propagation algorithm is impacted both positively and negatively by a reduction in the precision of the computation. Reducing precision reduces the coding gain, but the limited-precision computation can operate faster. A proposed solution offers custom logic to perform computations with less precision, yet uses the floating-point format to interface with the software. Simulation results show the achievable coding gain. Synthesis results help theorize the the full capacity and performance of an FPGA-based coprocessor.

A software reconfigurable optical multiband UWB system utilizing a bit-loading combined with adaptive LDPC code rate scheme

NASA Astrophysics Data System (ADS)

He, Jing; Dai, Min; Chen, Qinghui; Deng, Rui; Xiang, Changqing; Chen, Lin

2017-07-01

In this paper, an effective bit-loading combined with adaptive LDPC code rate algorithm is proposed and investigated in software reconfigurable multiband UWB over fiber system. To compensate the power fading and chromatic dispersion for the high frequency of multiband OFDM UWB signal transmission over standard single mode fiber (SSMF), a Mach-Zehnder modulator (MZM) with negative chirp parameter is utilized. In addition, the negative power penalty of -1 dB for 128 QAM multiband OFDM UWB signal are measured at the hard-decision forward error correction (HD-FEC) limitation of 3.8 × 10-3 after 50 km SSMF transmission. The experimental results show that, compared to the fixed coding scheme with the code rate of 75%, the signal-to-noise (SNR) is improved by 2.79 dB for 128 QAM multiband OFDM UWB system after 100 km SSMF transmission using ALCR algorithm. Moreover, by employing bit-loading combined with ALCR algorithm, the bit error rate (BER) performance of system can be further promoted effectively. The simulation results present that, at the HD-FEC limitation, the value of Q factor is improved by 3.93 dB at the SNR of 19.5 dB over 100 km SSMF transmission, compared to the fixed modulation with uncoded scheme at the same spectrum efficiency (SE).

Finite-connectivity spin-glass phase diagrams and low-density parity check codes.

PubMed

Migliorini, Gabriele; Saad, David

2006-02-01

We obtain phase diagrams of regular and irregular finite-connectivity spin glasses. Contact is first established between properties of the phase diagram and the performance of low-density parity check (LDPC) codes within the replica symmetric (RS) ansatz. We then study the location of the dynamical and critical transition points of these systems within the one step replica symmetry breaking theory (RSB), extending similar calculations that have been performed in the past for the Bethe spin-glass problem. We observe that the location of the dynamical transition line does change within the RSB theory, in comparison with the results obtained in the RS case. For LDPC decoding of messages transmitted over the binary erasure channel we find, at zero temperature and rate , an RS critical transition point at while the critical RSB transition point is located at , to be compared with the corresponding Shannon bound . For the binary symmetric channel we show that the low temperature reentrant behavior of the dynamical transition line, observed within the RS ansatz, changes its location when the RSB ansatz is employed; the dynamical transition point occurs at higher values of the channel noise. Possible practical implications to improve the performance of the state-of-the-art error correcting codes are discussed.

Advanced error-prediction LDPC with temperature compensation for highly reliable SSDs

NASA Astrophysics Data System (ADS)

Tokutomi, Tsukasa; Tanakamaru, Shuhei; Iwasaki, Tomoko Ogura; Takeuchi, Ken

2015-09-01

To improve the reliability of NAND Flash memory based solid-state drives (SSDs), error-prediction LDPC (EP-LDPC) has been proposed for multi-level-cell (MLC) NAND Flash memory (Tanakamaru et al., 2012, 2013), which is effective for long retention times. However, EP-LDPC is not as effective for triple-level cell (TLC) NAND Flash memory, because TLC NAND Flash has higher error rates and is more sensitive to program-disturb error. Therefore, advanced error-prediction LDPC (AEP-LDPC) has been proposed for TLC NAND Flash memory (Tokutomi et al., 2014). AEP-LDPC can correct errors more accurately by precisely describing the error phenomena. In this paper, the effects of AEP-LDPC are investigated in a 2×nm TLC NAND Flash memory with temperature characterization. Compared with LDPC-with-BER-only, the SSD's data-retention time is increased by 3.4× and 9.5× at room-temperature (RT) and 85 °C, respectively. Similarly, the acceptable BER is increased by 1.8× and 2.3×, respectively. Moreover, AEP-LDPC can correct errors with pre-determined tables made at higher temperatures to shorten the measurement time before shipping. Furthermore, it is found that one table can cover behavior over a range of temperatures in AEP-LDPC. As a result, the total table size can be reduced to 777 kBytes, which makes this approach more practical.

Sparsening Filter Design for Iterative Soft-Input Soft-Output Detectors

DTIC Science & Technology

2012-02-29

filter/detector structure. Since the BP detector itself is unaltered from [1], it can accommodate a system employing channel codes such as LDPC encoding...considered in [1], or can readily be extended to the MIMO case with, for example, space-time coding as in [2,8]. Since our focus is on the design of...simplex method of [15], since it was already available in Matlab , via the “fminsearch” function. 6 Cost surfaces To visualize the cost surfaces, consider

Joint Carrier-Phase Synchronization and LDPC Decoding

NASA Technical Reports Server (NTRS)

Simon, Marvin; Valles, Esteban

2009-01-01

A method has been proposed to increase the degree of synchronization of a radio receiver with the phase of a suppressed carrier signal modulated with a binary- phase-shift-keying (BPSK) or quaternary- phase-shift-keying (QPSK) signal representing a low-density parity-check (LDPC) code. This method is an extended version of the method described in Using LDPC Code Constraints to Aid Recovery of Symbol Timing (NPO-43112), NASA Tech Briefs, Vol. 32, No. 10 (October 2008), page 54. Both methods and the receiver architectures in which they would be implemented belong to a class of timing- recovery methods and corresponding receiver architectures characterized as pilotless in that they do not require transmission and reception of pilot signals. The proposed method calls for the use of what is known in the art as soft decision feedback to remove the modulation from a replica of the incoming signal prior to feeding this replica to a phase-locked loop (PLL) or other carrier-tracking stage in the receiver. Soft decision feedback refers to suitably processed versions of intermediate results of iterative computations involved in the LDPC decoding process. Unlike a related prior method in which hard decision feedback (the final sequence of decoded symbols) is used to remove the modulation, the proposed method does not require estimation of the decoder error probability. In a basic digital implementation of the proposed method, the incoming signal (having carrier phase theta theta (sub c) plus noise would first be converted to inphase (I) and quadrature (Q) baseband signals by mixing it with I and Q signals at the carrier frequency [wc/(2 pi)] generated by a local oscillator. The resulting demodulated signals would be processed through one-symbol-period integrate and- dump filters, the outputs of which would be sampled and held, then multiplied by a soft-decision version of the baseband modulated signal. The resulting I and Q products consist of terms proportional to the cosine and sine of the carrier phase cc as well as correlated noise components. These products would be fed as inputs to a digital PLL that would include a number-controlled oscillator (NCO), which provides an estimate of the carrier phase, theta(sub c).

Low-Density Parity-Check Code Design Techniques to Simplify Encoding

NASA Astrophysics Data System (ADS)

Perez, J. M.; Andrews, K.

2007-11-01

This work describes a method for encoding low-density parity-check (LDPC) codes based on the accumulate-repeat-4-jagged-accumulate (AR4JA) scheme, using the low-density parity-check matrix H instead of the dense generator matrix G. The use of the H matrix to encode allows a significant reduction in memory consumption and provides the encoder design a great flexibility. Also described are new hardware-efficient codes, based on the same kind of protographs, which require less memory storage and area, allowing at the same time a reduction in the encoding delay.

System on a Chip Real-Time Emulation (SOCRE)

DTIC Science & Technology

2006-09-01

code ) i Table of Contents Preface...emulation platform included LDPC decoders, A/V and radio applications Port BEE flow to Emulation Platforms, SOC Technologies One of the key tasks of the...Once the design has been described within Simulink, the designer runs the BEE design flow within Matlab using the bee_xps interface. At this point

Coded Modulation in C and MATLAB

NASA Technical Reports Server (NTRS)

Hamkins, Jon; Andrews, Kenneth S.

2011-01-01

This software, written separately in C and MATLAB as stand-alone packages with equivalent functionality, implements encoders and decoders for a set of nine error-correcting codes and modulators and demodulators for five modulation types. The software can be used as a single program to simulate the performance of such coded modulation. The error-correcting codes implemented are the nine accumulate repeat-4 jagged accumulate (AR4JA) low-density parity-check (LDPC) codes, which have been approved for international standardization by the Consultative Committee for Space Data Systems, and which are scheduled to fly on a series of NASA missions in the Constellation Program. The software implements the encoder and decoder functions, and contains compressed versions of generator and parity-check matrices used in these operations.

Low-complexity video encoding method for wireless image transmission in capsule endoscope.

PubMed

Takizawa, Kenichi; Hamaguchi, Kiyoshi

2010-01-01

This paper presents a low-complexity video encoding method applicable for wireless image transmission in capsule endoscopes. This encoding method is based on Wyner-Ziv theory, in which side information available at a transmitter is treated as side information at its receiver. Therefore complex processes in video encoding, such as estimation of the motion vector, are moved to the receiver side, which has a larger-capacity battery. As a result, the encoding process is only to decimate coded original data through channel coding. We provide a performance evaluation for a low-density parity check (LDPC) coding method in the AWGN channel.

High performance and cost effective CO-OFDM system aided by polar code.

PubMed

Liu, Ling; Xiao, Shilin; Fang, Jiafei; Zhang, Lu; Zhang, Yunhao; Bi, Meihua; Hu, Weisheng

2017-02-06

A novel polar coded coherent optical orthogonal frequency division multiplexing (CO-OFDM) system is proposed and demonstrated through experiment for the first time. The principle of a polar coded CO-OFDM signal is illustrated theoretically and the suitable polar decoding method is discussed. Results show that the polar coded CO-OFDM signal achieves a net coding gain (NCG) of more than 10 dB at bit error rate (BER) of 10^-3 over 25-Gb/s 480-km transmission in comparison with conventional CO-OFDM. Also, compared to the 25-Gb/s low-density parity-check (LDPC) coded CO-OFDM 160-km system, the polar code provides a NCG of 0.88 dB @BER = 10^-3. Moreover, the polar code can relieve the laser linewidth requirement massively to get a more cost-effective CO-OFDM system.

Performance of Low-Density Parity-Check Coded Modulation

NASA Technical Reports Server (NTRS)

Hamkins, Jon

2010-01-01

This paper reports the simulated performance of each of the nine accumulate-repeat-4-jagged-accumulate (AR4JA) low-density parity-check (LDPC) codes [3] when used in conjunction with binary phase-shift-keying (BPSK), quadrature PSK (QPSK), 8-PSK, 16-ary amplitude PSK (16- APSK), and 32-APSK.We also report the performance under various mappings of bits to modulation symbols, 16-APSK and 32-APSK ring scalings, log-likelihood ratio (LLR) approximations, and decoder variations. One of the simple and well-performing LLR approximations can be expressed in a general equation that applies to all of the modulation types.

Future capabilities for the Deep Space Network

NASA Technical Reports Server (NTRS)

Berner, J. B.; Bryant, S. H.; Andrews, K. S.

2004-01-01

This paper will look at three new capabilities that are in different stages of development. First, turbo decoding, which provides improved telemetry performance for data rates up to about 1 Mbps, will be discussed. Next, pseudo-noise ranging will be presented. Pseudo-noise ranging has several advantages over the current sequential ranging, anmely easier operations, improved performance, and the capability to be used in a regenerative implementation on a spacecraft. Finally, Low Density Parity Check decoding will be discussed. LDPC codes can provide performance that matches or slightly exceed turbo codes, but are designed for use in the 10 Mbps range.

16QAM transmission with 5.2 bits/s/Hz spectral efficiency over transoceanic distance.

PubMed

Zhang, H; Cai, J-X; Batshon, H G; Davidson, C R; Sun, Y; Mazurczyk, M; Foursa, D G; Pilipetskii, A; Mohs, G; Bergano, Neal S

2012-05-21

We transmit 160 x 100 G PDM RZ 16 QAM channels with 5.2 bits/s/Hz spectral efficiency over 6,860 km. There are more than 3 billion 16 QAM symbols, i.e., 12 billion bits, processed in total. Using coded modulation and iterative decoding between a MAP decoder and an LDPC based FEC all channels are decoded with no remaining errors.

Modified hybrid subcarrier/amplitude/ phase/polarization LDPC-coded modulation for 400 Gb/s optical transmission and beyond.

PubMed

Batshon, Hussam G; Djordjevic, Ivan; Xu, Lei; Wang, Ting

2010-06-21

In this paper, we present a modified coded hybrid subcarrier/ amplitude/phase/polarization (H-SAPP) modulation scheme as a technique capable of achieving beyond 400 Gb/s single-channel transmission over optical channels. The modified H-SAPP scheme profits from the available resources in addition to geometry to increase the bandwidth efficiency of the transmission system, and so increases the aggregate rate of the system. In this report we present the modified H-SAPP scheme and focus on an example that allows 11 bits/Symbol that can achieve 440 Gb/s transmission using components of 50 Giga Symbol/s (GS/s).

Frame Synchronization Without Attached Sync Markers

NASA Technical Reports Server (NTRS)

Hamkins, Jon

2011-01-01

We describe a method to synchronize codeword frames without making use of attached synchronization markers (ASMs). Instead, the synchronizer identifies the code structure present in the received symbols, by operating the decoder for a handful of iterations at each possible symbol offset and forming an appropriate metric. This method is computationally more complex and doesn't perform as well as frame synchronizers that utilize an ASM; nevertheless, the new synchronizer acquires frame synchronization in about two seconds when using a 600 kbps software decoder, and would take about 15 milliseconds on prototype hardware. It also eliminates the need for the ASMs, which is an attractive feature for short uplink codes whose coding gain would be diminished by the overheard of ASM bits. The lack of ASMs also would simplify clock distribution for the AR4JA low-density parity-check (LDPC) codes and adds a small amount to the coding gain as well (up to 0.2 dB).

Two high-density recording methods with run-length limited turbo code for holographic data storage system

NASA Astrophysics Data System (ADS)

Nakamura, Yusuke; Hoshizawa, Taku

2016-09-01

Two methods for increasing the data capacity of a holographic data storage system (HDSS) were developed. The first method is called “run-length-limited (RLL) high-density recording”. An RLL modulation has the same effect as enlarging the pixel pitch; namely, it optically reduces the hologram size. Accordingly, the method doubles the raw-data recording density. The second method is called “RLL turbo signal processing”. The RLL turbo code consists of \\text{RLL}(1,∞ ) trellis modulation and an optimized convolutional code. The remarkable point of the developed turbo code is that it employs the RLL modulator and demodulator as parts of the error-correction process. The turbo code improves the capability of error correction more than a conventional LDPC code, even though interpixel interference is generated. These two methods will increase the data density 1.78-fold. Moreover, by simulation and experiment, a data density of 2.4 Tbit/in.2 is confirmed.

Design space exploration of high throughput finite field multipliers for channel coding on Xilinx FPGAs

NASA Astrophysics Data System (ADS)

de Schryver, C.; Weithoffer, S.; Wasenmüller, U.; Wehn, N.

2012-09-01

Channel coding is a standard technique in all wireless communication systems. In addition to the typically employed methods like convolutional coding, turbo coding or low density parity check (LDPC) coding, algebraic codes are used in many cases. For example, outer BCH coding is applied in the DVB-S2 standard for satellite TV broadcasting. A key operation for BCH and the related Reed-Solomon codes are multiplications in finite fields (Galois Fields), where extension fields of prime fields are used. A lot of architectures for multiplications in finite fields have been published over the last decades. This paper examines four different multiplier architectures in detail that offer the potential for very high throughputs. We investigate the implementation performance of these multipliers on FPGA technology in the context of channel coding. We study the efficiency of the multipliers with respect to area, frequency and throughput, as well as configurability and scalability. The implementation data of the fully verified circuits are provided for a Xilinx Virtex-4 device after place and route.

Potts glass reflection of the decoding threshold for qudit quantum error correcting codes

NASA Astrophysics Data System (ADS)

Jiang, Yi; Kovalev, Alexey A.; Pryadko, Leonid P.

We map the maximum likelihood decoding threshold for qudit quantum error correcting codes to the multicritical point in generalized Potts gauge glass models, extending the map constructed previously for qubit codes. An n-qudit quantum LDPC code, where a qudit can be involved in up to m stabilizer generators, corresponds to a ℤd Potts model with n interaction terms which can couple up to m spins each. We analyze general properties of the phase diagram of the constructed model, give several bounds on the location of the transitions, bounds on the energy density of extended defects (non-local analogs of domain walls), and discuss the correlation functions which can be used to distinguish different phases in the original and the dual models. This research was supported in part by the Grants: NSF PHY-1415600 (AAK), NSF PHY-1416578 (LPP), and ARO W911NF-14-1-0272 (LPP).

Layered Wyner-Ziv video coding.

PubMed

Xu, Qian; Xiong, Zixiang

2006-12-01

Following recent theoretical works on successive Wyner-Ziv coding (WZC), we propose a practical layered Wyner-Ziv video coder using the DCT, nested scalar quantization, and irregular LDPC code based Slepian-Wolf coding (or lossless source coding with side information at the decoder). Our main novelty is to use the base layer of a standard scalable video coder (e.g., MPEG-4/H.26L FGS or H.263+) as the decoder side information and perform layered WZC for quality enhancement. Similar to FGS coding, there is no performance difference between layered and monolithic WZC when the enhancement bitstream is generated in our proposed coder. Using an H.26L coded version as the base layer, experiments indicate that WZC gives slightly worse performance than FGS coding when the channel (for both the base and enhancement layers) is noiseless. However, when the channel is noisy, extensive simulations of video transmission over wireless networks conforming to the CDMA2000 1X standard show that H.26L base layer coding plus Wyner-Ziv enhancement layer coding are more robust against channel errors than H.26L FGS coding. These results demonstrate that layered Wyner-Ziv video coding is a promising new technique for video streaming over wireless networks.

High-Performance CCSDS AOS Protocol Implementation in FPGA

NASA Technical Reports Server (NTRS)

Clare, Loren P.; Torgerson, Jordan L.; Pang, Jackson

2010-01-01

The Consultative Committee for Space Data Systems (CCSDS) Advanced Orbiting Systems (AOS) space data link protocol provides a framing layer between channel coding such as LDPC (low-density parity-check) and higher-layer link multiplexing protocols such as CCSDS Encapsulation Service, which is described in the following article. Recent advancement in RF modem technology has allowed multi-megabit transmission over space links. With this increase in data rate, the CCSDS AOS protocol implementation needs to be optimized to both reduce energy consumption and operate at a high rate.

SCaN Network Ground Station Receiver Performance for Future Service Support

NASA Technical Reports Server (NTRS)

Estabrook, Polly; Lee, Dennis; Cheng, Michael; Lau, Chi-Wung

2012-01-01

Objectives: Examine the impact of providing the newly standardized CCSDS Low Density Parity Check (LDPC) codes to the SCaN return data service on the SCaN SN and DSN ground stations receivers: SN Current Receiver: Integrated Receiver (IR). DSN Current Receiver: Downlink Telemetry and Tracking (DTT) Receiver. Early Commercial-Off-The-Shelf (COTS) prototype of the SN User Service Subsystem Component Replacement (USS CR) Narrow Band Receiver. Motivate discussion of general issues of ground station hardware design to enable simple and cheap modifications for support of future services.

Constellation labeling optimization for bit-interleaved coded APSK

NASA Astrophysics Data System (ADS)

Xiang, Xingyu; Mo, Zijian; Wang, Zhonghai; Pham, Khanh; Blasch, Erik; Chen, Genshe

2016-05-01

This paper investigates the constellation and mapping optimization for amplitude phase shift keying (APSK) modulation, which is deployed in Digital Video Broadcasting Satellite - Second Generation (DVB-S2) and Digital Video Broadcasting - Satellite services to Handhelds (DVB-SH) broadcasting standards due to its merits of power and spectral efficiency together with the robustness against nonlinear distortion. The mapping optimization is performed for 32-APSK according to combined cost functions related to Euclidean distance and mutual information. A Binary switching algorithm and its modified version are used to minimize the cost function and the estimated error between the original and received data. The optimized constellation mapping is tested by combining DVB-S2 standard Low-Density Parity-Check (LDPC) codes in both Bit-Interleaved Coded Modulation (BICM) and BICM with iterative decoding (BICM-ID) systems. The simulated results validate the proposed constellation labeling optimization scheme which yields better performance against conventional 32-APSK constellation defined in DVB-S2 standard.

Mechanisms of lectin and antibody-dependent polymorphonuclear leukocyte-mediated cytolysis.

PubMed

Tsunawaki, S; Ikenami, M; Mizuno, D; Yamazaki, M

1983-04-01

The mechanisms of tumor lysis by polymorphonuclear leukocytes (PMNs) were investigated. In antibody-dependent PMN-mediated cytolysis (ADPC), sensitized tumor cells were specifically lysed via Fc receptors on PMNs. On the other hand, lectin-dependent PMN-mediated cytolysis (LDPC) caused nonspecific lysis of several murine tumors after recognition of carbohydrate moieties on the cell membrane of both PMNs and tumor cells. Both ADPC and LDPC depended on glycolysis, and cytotoxicity was mediated by reactive oxygen species; LDPC was dependent on superoxide and ADPC on the myeloperoxidase system. The participation of reactive oxygen species in PMN cytotoxicity was also demonstrated by pharmacological triggering with phorbol myristate acetate. These results indicate that reactive oxygen species have an important role In tumor killing by PMNs and that ADPC and LDPC have partly different cytolytic processes as well as different recognition steps.

Progressive transmission of images over fading channels using rate-compatible LDPC codes.

PubMed

Pan, Xiang; Banihashemi, Amir H; Cuhadar, Aysegul

2006-12-01

In this paper, we propose a combined source/channel coding scheme for transmission of images over fading channels. The proposed scheme employs rate-compatible low-density parity-check codes along with embedded image coders such as JPEG2000 and set partitioning in hierarchical trees (SPIHT). The assignment of channel coding rates to source packets is performed by a fast trellis-based algorithm. We examine the performance of the proposed scheme over correlated and uncorrelated Rayleigh flat-fading channels with and without side information. Simulation results for the expected peak signal-to-noise ratio of reconstructed images, which are within 1 dB of the capacity upper bound over a wide range of channel signal-to-noise ratios, show considerable improvement compared to existing results under similar conditions. We also study the sensitivity of the proposed scheme in the presence of channel estimation error at the transmitter and demonstrate that under most conditions our scheme is more robust compared to existing schemes.

NASA Tech Briefs, October 2009

NASA Technical Reports Server (NTRS)

2009-01-01

Topics covered include: Light-Driven Polymeric Bimorph Actuators; Guaranteeing Failsafe Operation of Extended-Scene Shack-Hartmann Wavefront Sensor Algorithm; Cloud Water Content Sensor for Sounding Balloons and Small UAVs; Pixelized Device Control Actuators for Large Adaptive Optics; T-Slide Linear Actuators; G4FET Implementations of Some Logic Circuits; Electrically Variable or Programmable Nonvolatile Capacitors; System for Automated Calibration of Vector Modulators; Complementary Paired G4FETs as Voltage-Controlled NDR Device; Three MMIC Amplifiers for the 120-to-200 GHz Frequency Band; Low-Noise MMIC Amplifiers for 120 to 180 GHz; Using Ozone To Clean and Passivate Oxygen-Handling Hardware; Metal Standards for Waveguide Characterization of Materials; Two-Piece Screens for Decontaminating Granular Material; Mercuric Iodide Anticoincidence Shield for Gamma-Ray Spectrometer; Improved Method of Design for Folding Inflatable Shells; Ultra-Large Solar Sail; Cooperative Three-Robot System for Traversing Steep Slopes; Assemblies of Conformal Tanks; Microfluidic Pumps Containing Teflon[Trademark] AF Diaphragms; Transparent Conveyor of Dielectric Liquids or Particles; Multi-Cone Model for Estimating GPS Ionospheric Delays; High-Sensitivity GaN Microchemical Sensors; On the Divergence of the Velocity Vector in Real-Gas Flow; Progress Toward a Compact, Highly Stable Ion Clock; Instruments for Imaging from Far to Near; Reflectors Made from Membranes Stretched Between Beams; Integrated Risk and Knowledge Management Program -- IRKM-P; LDPC Codes with Minimum Distance Proportional to Block Size; Constructing LDPC Codes from Loop-Free Encoding Modules; MMICs with Radial Probe Transitions to Waveguides; Tests of Low-Noise MMIC Amplifier Module at 290 to 340 GHz; and Extending Newtonian Dynamics to Include Stochastic Processes.

Design and Implementation of Secure and Reliable Communication using Optical Wireless Communication

NASA Astrophysics Data System (ADS)

Saadi, Muhammad; Bajpai, Ambar; Zhao, Yan; Sangwongngam, Paramin; Wuttisittikulkij, Lunchakorn

2014-11-01

Wireless networking intensify the tractability in the home and office environment to connect the internet without wires but at the cost of risks associated with stealing the data or threat of loading malicious code with the intention of harming the network. In this paper, we proposed a novel method of establishing a secure and reliable communication link using optical wireless communication (OWC). For security, spatial diversity based transmission using two optical transmitters is used and the reliability in the link is achieved by a newly proposed method for the construction of structured parity check matrix for binary Low Density Parity Check (LDPC) codes. Experimental results show that a successful secure and reliable link between the transmitter and the receiver can be achieved by using the proposed novel technique.

25 Tb/s transmission over 5,530 km using 16QAM at 5.2 b/s/Hz spectral efficiency.

PubMed

Cai, J-X; Batshon, H G; Zhang, H; Davidson, C R; Sun, Y; Mazurczyk, M; Foursa, D G; Sinkin, O; Pilipetskii, A; Mohs, G; Bergano, Neal S

2013-01-28

We transmit 250x100G PDM RZ-16QAM channels with 5.2 b/s/Hz spectral efficiency over 5,530 km using single-stage C-band EDFAs equalized to 40 nm. We use single parity check coded modulation and all channels are decoded with no errors after iterative decoding between a MAP decoder and an LDPC based FEC algorithm. We also observe that the optimum power spectral density is nearly independent of SE, signal baud rate or modulation format in a dispersion uncompensated system.

Quick-low-density parity check and dynamic threshold voltage optimization in 1X nm triple-level cell NAND flash memory with comprehensive analysis of endurance, retention-time, and temperature variation

NASA Astrophysics Data System (ADS)

Doi, Masafumi; Tokutomi, Tsukasa; Hachiya, Shogo; Kobayashi, Atsuro; Tanakamaru, Shuhei; Ning, Sheyang; Ogura Iwasaki, Tomoko; Takeuchi, Ken

2016-08-01

NAND flash memory’s reliability degrades with increasing endurance, retention-time and/or temperature. After a comprehensive evaluation of 1X nm triple-level cell (TLC) NAND flash, two highly reliable techniques are proposed. The first proposal, quick low-density parity check (Quick-LDPC), requires only one cell read in order to accurately estimate a bit-error rate (BER) that includes the effects of temperature, write and erase (W/E) cycles and retention-time. As a result, 83% read latency reduction is achieved compared to conventional AEP-LDPC. Also, W/E cycling is extended by 100% compared with conventional Bose-Chaudhuri-Hocquenghem (BCH) error-correcting code (ECC). The second proposal, dynamic threshold voltage optimization (DVO) has two parts, adaptive V Ref shift (AVS) and V TH space control (VSC). AVS reduces read error and latency by adaptively optimizing the reference voltage (V Ref) based on temperature, W/E cycles and retention-time. AVS stores the optimal V Ref’s in a table in order to enable one cell read. VSC further improves AVS by optimizing the voltage margins between V TH states. DVO reduces BER by 80%.

Adaptive channel estimation for soft decision decoding over non-Gaussian optical channel

NASA Astrophysics Data System (ADS)

Xiang, Jing-song; Miao, Tao-tao; Huang, Sheng; Liu, Huan-lin

2016-10-01

An adaptive priori likelihood ratio (LLR) estimation method is proposed over non-Gaussian channel in the intensity modulation/direct detection (IM/DD) optical communication systems. Using the nonparametric histogram and the weighted least square linear fitting in the tail regions, the LLR is estimated and used for the soft decision decoding of the low-density parity-check (LDPC) codes. This method can adapt well to the three main kinds of intensity modulation/direct detection (IM/DD) optical channel, i.e., the chi-square channel, the Webb-Gaussian channel and the additive white Gaussian noise (AWGN) channel. The performance penalty of channel estimation is neglected.

Analysis of soft-decision FEC on non-AWGN channels.

PubMed

Cho, Junho; Xie, Chongjin; Winzer, Peter J

2012-03-26

Soft-decision forward error correction (SD-FEC) schemes are typically designed for additive white Gaussian noise (AWGN) channels. In a fiber-optic communication system, noise may be neither circularly symmetric nor Gaussian, thus violating an important assumption underlying SD-FEC design. This paper quantifies the impact of non-AWGN noise on SD-FEC performance for such optical channels. We use a conditionally bivariate Gaussian noise model (CBGN) to analyze the impact of correlations among the signal's two quadrature components, and assess the effect of CBGN on SD-FEC performance using the density evolution of low-density parity-check (LDPC) codes. On a CBGN channel generating severely elliptic noise clouds, it is shown that more than 3 dB of coding gain are attainable by utilizing correlation information. Our analyses also give insights into potential improvements of the detection performance for fiber-optic transmission systems assisted by SD-FEC.

Co-operation of digital nonlinear equalizers and soft-decision LDPC FEC in nonlinear transmission.

PubMed

Tanimura, Takahito; Oda, Shoichiro; Hoshida, Takeshi; Aoki, Yasuhiko; Tao, Zhenning; Rasmussen, Jens C

2013-12-30

We experimentally and numerically investigated the characteristics of 128 Gb/s dual polarization - quadrature phase shift keying signals received with two types of nonlinear equalizers (NLEs) followed by soft-decision (SD) low-density parity-check (LDPC) forward error correction (FEC). Successful co-operation among SD-FEC and NLEs over various nonlinear transmissions were demonstrated by optimization of parameters for NLEs.

Analysis on applicable error-correcting code strength of storage class memory and NAND flash in hybrid storage

NASA Astrophysics Data System (ADS)

Matsui, Chihiro; Kinoshita, Reika; Takeuchi, Ken

2018-04-01

A hybrid of storage class memory (SCM) and NAND flash is a promising technology for high performance storage. Error correction is inevitable on SCM and NAND flash because their bit error rate (BER) increases with write/erase (W/E) cycles, data retention, and program/read disturb. In addition, scaling and multi-level cell technologies increase BER. However, error-correcting code (ECC) degrades storage performance because of extra memory reading and encoding/decoding time. Therefore, applicable ECC strength of SCM and NAND flash is evaluated independently by fixing ECC strength of one memory in the hybrid storage. As a result, weak BCH ECC with small correctable bit is recommended for the hybrid storage with large SCM capacity because SCM is accessed frequently. In contrast, strong and long-latency LDPC ECC can be applied to NAND flash in the hybrid storage with large SCM capacity because large-capacity SCM improves the storage performance.

Characterization of vibrissa germinative cells: transition of cell types.

PubMed

Osada, A; Kobayashi, K

2001-12-01

Germinative cells, small cell masses attached to the stalks of dermal papillae that are able to differentiate into the hair shaft and inner root sheath, form follicular bulb-like structures when co-cultured with dermal papilla cells. We studied the growth characteristics of germinative cells to determine the cell types in the vibrissa germinative tissue. Germinative tissues, attaching to dermal papillae, were cultured on 3T3 feeder layers. The cultured keratinocytes were harvested and transferred, equally and for two passages, onto lined dermal papilla cells (LDPC) and/or 3T3 feeder layers. The resulting germinative cells were classified into three types in the present experimental condition. Type 1 cells grow very well on either feeder layer, whereas Type 3 cells scarcely grow on either feeder layer. Type 2 cells are very conspicuous and are reversible. They grow well on 3T3 but growth is suppressed on LDPC feeder layers. The Type 2 cells that grow well on 3T3 feeder layers, however, are suppressed when transferred onto LDPC and the Type 2 cells that are suppressed on LDPC begin to grow again on 3T3. The transition of one cell type to another in vitro and the cell types that these germinative cell types correspond to in vivo is discussed. It was concluded that stem cells or their close progenitors reside in the germinative tissues of the vibrissa bulb except at late anagen-early catagen.

On the photonic implementation of universal quantum gates, bell states preparation circuit and quantum LDPC encoders and decoders based on directional couplers and HNLF.

PubMed

Djordjevic, Ivan B

2010-04-12

The Bell states preparation circuit is a basic circuit required in quantum teleportation. We describe how to implement it in all-fiber technology. The basic building blocks for its implementation are directional couplers and highly nonlinear optical fiber (HNLF). Because the quantum information processing is based on delicate superposition states, it is sensitive to quantum errors. In order to enable fault-tolerant quantum computing the use of quantum error correction is unavoidable. We show how to implement in all-fiber technology encoders and decoders for sparse-graph quantum codes, and provide an illustrative example to demonstrate this implementation. We also show that arbitrary set of universal quantum gates can be implemented based on directional couplers and HNLFs.

A burst-mode photon counting receiver with automatic channel estimation and bit rate detection

NASA Astrophysics Data System (ADS)

Rao, Hemonth G.; DeVoe, Catherine E.; Fletcher, Andrew S.; Gaschits, Igor D.; Hakimi, Farhad; Hamilton, Scott A.; Hardy, Nicholas D.; Ingwersen, John G.; Kaminsky, Richard D.; Moores, John D.; Scheinbart, Marvin S.; Yarnall, Timothy M.

2016-04-01

We demonstrate a multi-rate burst-mode photon-counting receiver for undersea communication at data rates up to 10.416 Mb/s over a 30-foot water channel. To the best of our knowledge, this is the first demonstration of burst-mode photon-counting communication. With added attenuation, the maximum link loss is 97.1 dB at λ=517 nm. In clear ocean water, this equates to link distances up to 148 meters. For λ=470 nm, the achievable link distance in clear ocean water is 450 meters. The receiver incorporates soft-decision forward error correction (FEC) based on a product code of an inner LDPC code and an outer BCH code. The FEC supports multiple code rates to achieve error-free performance. We have selected a burst-mode receiver architecture to provide robust performance with respect to unpredictable channel obstructions. The receiver is capable of on-the-fly data rate detection and adapts to changing levels of signal and background light. The receiver updates its phase alignment and channel estimates every 1.6 ms, allowing for rapid changes in water quality as well as motion between transmitter and receiver. We demonstrate on-the-fly rate detection, channel BER within 0.2 dB of theory across all data rates, and error-free performance within 1.82 dB of soft-decision capacity across all tested code rates. All signal processing is done in FPGAs and runs continuously in real time.

Direct-detection Free-space Laser Transceiver Test-bed

NASA Technical Reports Server (NTRS)

Krainak, Michael A.; Chen, Jeffrey R.; Dabney, Philip W.; Ferrara, Jeffrey F.; Fong, Wai H.; Martino, Anthony J.; McGarry Jan. F.; Merkowitz, Stephen M.; Principe, Caleb M.; Sun, Siaoli;

Sum of the Magnitude for Hard Decision Decoding Algorithm Based on Loop Update Detection.

PubMed

Meng, Jiahui; Zhao, Danfeng; Tian, Hai; Zhang, Liang

2018-01-15

In order to improve the performance of non-binary low-density parity check codes (LDPC) hard decision decoding algorithm and to reduce the complexity of decoding, a sum of the magnitude for hard decision decoding algorithm based on loop update detection is proposed. This will also ensure the reliability, stability and high transmission rate of 5G mobile communication. The algorithm is based on the hard decision decoding algorithm (HDA) and uses the soft information from the channel to calculate the reliability, while the sum of the variable nodes' (VN) magnitude is excluded for computing the reliability of the parity checks. At the same time, the reliability information of the variable node is considered and the loop update detection algorithm is introduced. The bit corresponding to the error code word is flipped multiple times, before this is searched in the order of most likely error probability to finally find the correct code word. Simulation results show that the performance of one of the improved schemes is better than the weighted symbol flipping (WSF) algorithm under different hexadecimal numbers by about 2.2 dB and 2.35 dB at the bit error rate (BER) of 10 -5 over an additive white Gaussian noise (AWGN) channel, respectively. Furthermore, the average number of decoding iterations is significantly reduced.

The serial message-passing schedule for LDPC decoding algorithms

NASA Astrophysics Data System (ADS)

Liu, Mingshan; Liu, Shanshan; Zhou, Yuan; Jiang, Xue

2015-12-01

The conventional message-passing schedule for LDPC decoding algorithms is the so-called flooding schedule. It has the disadvantage that the updated messages cannot be used until next iteration, thus reducing the convergence speed . In this case, the Layered Decoding algorithm (LBP) based on serial message-passing schedule is proposed. In this paper the decoding principle of LBP algorithm is briefly introduced, and then proposed its two improved algorithms, the grouped serial decoding algorithm (Grouped LBP) and the semi-serial decoding algorithm .They can improve LBP algorithm's decoding speed while maintaining a good decoding performance.

Assessment of dedicated low-dose cardiac micro-CT reconstruction algorithms using the left ventricular volume of small rodents as a performance measure.

PubMed

Maier, Joscha; Sawall, Stefan; Kachelrieß, Marc

2014-05-01

Phase-correlated microcomputed tomography (micro-CT) imaging plays an important role in the assessment of mouse models of cardiovascular diseases and the determination of functional parameters as the left ventricular volume. As the current gold standard, the phase-correlated Feldkamp reconstruction (PCF), shows poor performance in case of low dose scans, more sophisticated reconstruction algorithms have been proposed to enable low-dose imaging. In this study, the authors focus on the McKinnon-Bates (MKB) algorithm, the low dose phase-correlated (LDPC) reconstruction, and the high-dimensional total variation minimization reconstruction (HDTV) and investigate their potential to accurately determine the left ventricular volume at different dose levels from 50 to 500 mGy. The results were verified in phantom studies of a five-dimensional (5D) mathematical mouse phantom. Micro-CT data of eight mice, each administered with an x-ray dose of 500 mGy, were acquired, retrospectively gated for cardiac and respiratory motion and reconstructed using PCF, MKB, LDPC, and HDTV. Dose levels down to 50 mGy were simulated by using only a fraction of the projections. Contrast-to-noise ratio (CNR) was evaluated as a measure of image quality. Left ventricular volume was determined using different segmentation algorithms (Otsu, level sets, region growing). Forward projections of the 5D mouse phantom were performed to simulate a micro-CT scan. The simulated data were processed the same way as the real mouse data sets. Compared to the conventional PCF reconstruction, the MKB, LDPC, and HDTV algorithm yield images of increased quality in terms of CNR. While the MKB reconstruction only provides small improvements, a significant increase of the CNR is observed in LDPC and HDTV reconstructions. The phantom studies demonstrate that left ventricular volumes can be determined accurately at 500 mGy. For lower dose levels which were simulated for real mouse data sets, the HDTV algorithm shows the best performance. At 50 mGy, the deviation from the reference obtained at 500 mGy were less than 4%. Also the LDPC algorithm provides reasonable results with deviation less than 10% at 50 mGy while PCF and MKB reconstruction show larger deviations even at higher dose levels. LDPC and HDTV increase CNR and allow for quantitative evaluations even at dose levels as low as 50 mGy. The left ventricular volumes exemplarily illustrate that cardiac parameters can be accurately estimated at lowest dose levels if sophisticated algorithms are used. This allows to reduce dose by a factor of 10 compared to today's gold standard and opens new options for longitudinal studies of the heart.

Assessment of dedicated low-dose cardiac micro-CT reconstruction algorithms using the left ventricular volume of small rodents as a performance measure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maier, Joscha, E-mail: joscha.maier@dkfz.de; Sawall, Stefan; Kachelrieß, Marc

2014-05-15

Purpose: Phase-correlated microcomputed tomography (micro-CT) imaging plays an important role in the assessment of mouse models of cardiovascular diseases and the determination of functional parameters as the left ventricular volume. As the current gold standard, the phase-correlated Feldkamp reconstruction (PCF), shows poor performance in case of low dose scans, more sophisticated reconstruction algorithms have been proposed to enable low-dose imaging. In this study, the authors focus on the McKinnon-Bates (MKB) algorithm, the low dose phase-correlated (LDPC) reconstruction, and the high-dimensional total variation minimization reconstruction (HDTV) and investigate their potential to accurately determine the left ventricular volume at different dose levelsmore » from 50 to 500 mGy. The results were verified in phantom studies of a five-dimensional (5D) mathematical mouse phantom. Methods: Micro-CT data of eight mice, each administered with an x-ray dose of 500 mGy, were acquired, retrospectively gated for cardiac and respiratory motion and reconstructed using PCF, MKB, LDPC, and HDTV. Dose levels down to 50 mGy were simulated by using only a fraction of the projections. Contrast-to-noise ratio (CNR) was evaluated as a measure of image quality. Left ventricular volume was determined using different segmentation algorithms (Otsu, level sets, region growing). Forward projections of the 5D mouse phantom were performed to simulate a micro-CT scan. The simulated data were processed the same way as the real mouse data sets. Results: Compared to the conventional PCF reconstruction, the MKB, LDPC, and HDTV algorithm yield images of increased quality in terms of CNR. While the MKB reconstruction only provides small improvements, a significant increase of the CNR is observed in LDPC and HDTV reconstructions. The phantom studies demonstrate that left ventricular volumes can be determined accurately at 500 mGy. For lower dose levels which were simulated for real mouse data sets, the HDTV algorithm shows the best performance. At 50 mGy, the deviation from the reference obtained at 500 mGy were less than 4%. Also the LDPC algorithm provides reasonable results with deviation less than 10% at 50 mGy while PCF and MKB reconstruction show larger deviations even at higher dose levels. Conclusions: LDPC and HDTV increase CNR and allow for quantitative evaluations even at dose levels as low as 50 mGy. The left ventricular volumes exemplarily illustrate that cardiac parameters can be accurately estimated at lowest dose levels if sophisticated algorithms are used. This allows to reduce dose by a factor of 10 compared to today's gold standard and opens new options for longitudinal studies of the heart.« less

Implementation of continuous-variable quantum key distribution with discrete modulation

NASA Astrophysics Data System (ADS)

Hirano, Takuya; Ichikawa, Tsubasa; Matsubara, Takuto; Ono, Motoharu; Oguri, Yusuke; Namiki, Ryo; Kasai, Kenta; Matsumoto, Ryutaroh; Tsurumaru, Toyohiro

2017-06-01

We have developed a continuous-variable quantum key distribution (CV-QKD) system that employs discrete quadrature-amplitude modulation and homodyne detection of coherent states of light. We experimentally demonstrated automated secure key generation with a rate of 50 kbps when a quantum channel is a 10 km optical fibre. The CV-QKD system utilises a four-state and post-selection protocol and generates a secure key against the entangling cloner attack. We used a pulsed light source of 1550 nm wavelength with a repetition rate of 10 MHz. A commercially available balanced receiver is used to realise shot-noise-limited pulsed homodyne detection. We used a non-binary LDPC code for error correction (reverse reconciliation) and the Toeplitz matrix multiplication for privacy amplification. A graphical processing unit card is used to accelerate the software-based post-processing.

NASA Tech Briefs, April 2009

NASA Technical Reports Server (NTRS)

2009-01-01

Topics covered include: Direct-Solve Image-Based Wavefront Sensing; Use of UV Sources for Detection and Identification of Explosives; Using Fluorescent Viruses for Detecting Bacteria in Water; Gradiometer Using Middle Loops as Sensing Elements in a Low-Field SQUID MRI System; Volcano Monitor: Autonomous Triggering of In-Situ Sensors; Wireless Fluid-Level Sensors for Harsh Environments; Interference-Detection Module in a Digital Radar Receiver; Modal Vibration Analysis of Large Castings; Structural/Radiation-Shielding Epoxies; Integrated Multilayer Insulation; Apparatus for Screening Multiple Oxygen-Reduction Catalysts; Determining Aliasing in Isolated Signal Conditioning Modules; Composite Bipolar Plate for Unitized Fuel Cell/Electrolyzer Systems; Spectrum Analyzers Incorporating Tunable WGM Resonators; Quantum-Well Thermophotovoltaic Cells; Bounded-Angle Iterative Decoding of LDPC Codes; Conversion from Tree to Graph Representation of Requirements; Parallel Hybrid Vehicle Optimal Storage System; and Anaerobic Digestion in a Flooded Densified Leachbed.

PPLN-waveguide-based polarization entangled QKD simulator

NASA Astrophysics Data System (ADS)

Gariano, John; Djordjevic, Ivan B.

2017-08-01

We have developed a comprehensive simulator to study the polarization entangled quantum key distribution (QKD) system, which takes various imperfections into account. We assume that a type-II SPDC source using a PPLN-based nonlinear optical waveguide is used to generate entangled photon pairs and implements the BB84 protocol, using two mutually unbiased basis with two orthogonal polarizations in each basis. The entangled photon pairs are then simulated to be transmitted to both parties; Alice and Bob, through the optical channel, imperfect optical elements and onto the imperfect detector. It is assumed that Eve has no control over the detectors, and can only gain information from the public channel and the intercept resend attack. The secure key rate (SKR) is calculated using an upper bound and by using actual code rates of LDPC codes implementable in FPGA hardware. After the verification of the simulation results, such as the pair generation rate and the number of error due to multiple pairs, for the ideal scenario, available in the literature, we then introduce various imperfections. Then, the results are compared to previously reported experimental results where a BBO nonlinear crystal is used, and the improvements in SKRs are determined for when a PPLN-waveguide is used instead.

Sum of the Magnitude for Hard Decision Decoding Algorithm Based on Loop Update Detection

PubMed Central

Meng, Jiahui; Zhao, Danfeng; Tian, Hai; Zhang, Liang

2018-01-01

In order to improve the performance of non-binary low-density parity check codes (LDPC) hard decision decoding algorithm and to reduce the complexity of decoding, a sum of the magnitude for hard decision decoding algorithm based on loop update detection is proposed. This will also ensure the reliability, stability and high transmission rate of 5G mobile communication. The algorithm is based on the hard decision decoding algorithm (HDA) and uses the soft information from the channel to calculate the reliability, while the sum of the variable nodes’ (VN) magnitude is excluded for computing the reliability of the parity checks. At the same time, the reliability information of the variable node is considered and the loop update detection algorithm is introduced. The bit corresponding to the error code word is flipped multiple times, before this is searched in the order of most likely error probability to finally find the correct code word. Simulation results show that the performance of one of the improved schemes is better than the weighted symbol flipping (WSF) algorithm under different hexadecimal numbers by about 2.2 dB and 2.35 dB at the bit error rate (BER) of 10−5 over an additive white Gaussian noise (AWGN) channel, respectively. Furthermore, the average number of decoding iterations is significantly reduced. PMID:29342963

Combining Ratio Estimation for Low Density Parity Check (LDPC) Coding

NASA Technical Reports Server (NTRS)

Mahmoud, Saad; Hi, Jianjun

2012-01-01

The Low Density Parity Check (LDPC) Code decoding algorithm make use of a scaled receive signal derived from maximizing the log-likelihood ratio of the received signal. The scaling factor (often called the combining ratio) in an AWGN channel is a ratio between signal amplitude and noise variance. Accurately estimating this ratio has shown as much as 0.6 dB decoding performance gain. This presentation briefly describes three methods for estimating the combining ratio: a Pilot-Guided estimation method, a Blind estimation method, and a Simulation-Based Look-Up table. The Pilot Guided Estimation method has shown that the maximum likelihood estimates of signal amplitude is the mean inner product of the received sequence and the known sequence, the attached synchronization marker (ASM) , and signal variance is the difference of the mean of the squared received sequence and the square of the signal amplitude. This method has the advantage of simplicity at the expense of latency since several frames worth of ASMs. The Blind estimation method s maximum likelihood estimator is the average of the product of the received signal with the hyperbolic tangent of the product combining ratio and the received signal. The root of this equation can be determined by an iterative binary search between 0 and 1 after normalizing the received sequence. This method has the benefit of requiring one frame of data to estimate the combining ratio which is good for faster changing channels compared to the previous method, however it is computationally expensive. The final method uses a look-up table based on prior simulated results to determine signal amplitude and noise variance. In this method the received mean signal strength is controlled to a constant soft decision value. The magnitude of the deviation is averaged over a predetermined number of samples. This value is referenced in a look up table to determine the combining ratio that prior simulation associated with the average magnitude of the deviation. This method is more complicated than the Pilot-Guided Method due to the gain control circuitry, but does not have the real-time computation complexity of the Blind Estimation method. Each of these methods can be used to provide an accurate estimation of the combining ratio, and the final selection of the estimation method depends on other design constraints.

Disclosure of terminal illness to patients and families: diversity of governing codes in 14 Islamic countries.

PubMed

Abdulhameed, Hunida E; Hammami, Muhammad M; Mohamed, Elbushra A Hameed

2011-08-01

The consistency of codes governing disclosure of terminal illness to patients and families in Islamic countries has not been studied until now. To review available codes on disclosure of terminal illness in Islamic countries. DATA SOURCE AND EXTRACTION: Data were extracted through searches on Google and PubMed. Codes related to disclosure of terminal illness to patients or families were abstracted, and then classified independently by the three authors. Codes for 14 Islamic countries were located. Five codes were silent regarding informing the patient, seven allowed concealment, one mandated disclosure and one prohibited disclosure. Five codes were silent regarding informing the family, four allowed disclosure and five mandated/recommended disclosure. The Islamic Organization for Medical Sciences code was silent on both issues. Codes regarding disclosure of terminal illness to patients and families differed markedly among Islamic countries. They were silent in one-third of the codes, and tended to favour a paternalistic/utilitarian, family-centred approach over an autonomous, patient-centred approach.

New quantum codes derived from a family of antiprimitive BCH codes

NASA Astrophysics Data System (ADS)

Liu, Yang; Li, Ruihu; Lü, Liangdong; Guo, Luobin

The Bose-Chaudhuri-Hocquenghem (BCH) codes have been studied for more than 57 years and have found wide application in classical communication system and quantum information theory. In this paper, we study the construction of quantum codes from a family of q2-ary BCH codes with length n=q2m+1 (also called antiprimitive BCH codes in the literature), where q≥4 is a power of 2 and m≥2. By a detailed analysis of some useful properties about q2-ary cyclotomic cosets modulo n, Hermitian dual-containing conditions for a family of non-narrow-sense antiprimitive BCH codes are presented, which are similar to those of q2-ary primitive BCH codes. Consequently, via Hermitian Construction, a family of new quantum codes can be derived from these dual-containing BCH codes. Some of these new antiprimitive quantum BCH codes are comparable with those derived from primitive BCH codes.

Simulation of ICD-9 to ICD-10-CM Transition for Family Medicine: Simple or Convoluted?

PubMed

Grief, Samuel N; Patel, Jesal; Kochendorfer, Karl M; Green, Lee A; Lussier, Yves A; Li, Jianrong; Burton, Michael; Boyd, Andrew D

2016-01-01

The objective of this study was to examine the impact of the transition from International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM), to Interactional Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM), on family medicine and to identify areas where additional training might be required. Family medicine ICD-9-CM codes were obtained from an Illinois Medicaid data set (113,000 patient visits and $5.5 million in claims). Using the science of networks, we evaluated each ICD-9-CM code used by family medicine physicians to determine whether the transition was simple or convoluted. A simple transition is defined as 1 ICD-9-CM code mapping to 1 ICD-10-CM code, or 1 ICD-9-CM code mapping to multiple ICD-10-CM codes. A convoluted transition is where the transitions between coding systems is nonreciprocal and complex, with multiple codes for which definitions become intertwined. Three family medicine physicians evaluated the most frequently encountered complex mappings for clinical accuracy. Of the 1635 diagnosis codes used by family medicine physicians, 70% of the codes were categorized as simple, 27% of codes were convoluted, and 3% had no mapping. For the visits, 75%, 24%, and 1% corresponded with simple, convoluted, and no mapping, respectively. Payment for submitted claims was similarly aligned. Of the frequently encountered convoluted codes, 3 diagnosis codes were clinically incorrect, but they represent only <0.1% of the overall diagnosis codes. The transition to ICD-10-CM is simple for 70% or more of diagnosis codes, visits, and reimbursement for a family medicine physician. However, some frequently used codes for disease management are convoluted and incorrect, and for which additional resources need to be invested to ensure a successful transition to ICD-10-CM. © Copyright 2016 by the American Board of Family Medicine.

Deep-space and near-Earth optical communications by coded orbital angular momentum (OAM) modulation.

PubMed

Djordjevic, Ivan B

2011-07-18

In order to achieve multi-gigabit transmission (projected for 2020) for the use in interplanetary communications, the usage of large number of time slots in pulse-position modulation (PPM), typically used in deep-space applications, is needed, which imposes stringent requirements on system design and implementation. As an alternative satisfying high-bandwidth demands of future interplanetary communications, while keeping the system cost and power consumption reasonably low, in this paper, we describe the use of orbital angular momentum (OAM) as an additional degree of freedom. The OAM is associated with azimuthal phase of the complex electric field. Because OAM eigenstates are orthogonal the can be used as basis functions for N-dimensional signaling. The OAM modulation and multiplexing can, therefore, be used, in combination with other degrees of freedom, to solve the high-bandwidth requirements of future deep-space and near-Earth optical communications. The main challenge for OAM deep-space communication represents the link between a spacecraft probe and the Earth station because in the presence of atmospheric turbulence the orthogonality between OAM states is no longer preserved. We will show that in combination with LDPC codes, the OAM-based modulation schemes can operate even under strong atmospheric turbulence regime. In addition, the spectral efficiency of proposed scheme is N2/log₂N times better than that of PPM.

New optimal asymmetric quantum codes constructed from constacyclic codes

NASA Astrophysics Data System (ADS)

Xu, Gen; Li, Ruihu; Guo, Luobin; Lü, Liangdong

2017-02-01

In this paper, we propose the construction of asymmetric quantum codes from two families of constacyclic codes over finite field 𝔽q2 of code length n, where for the first family, q is an odd prime power with the form 4t + 1 (t ≥ 1 is integer) or 4t - 1 (t ≥ 2 is integer) and n1 = q2+1 2; for the second family, q is an odd prime power with the form 10t + 3 or 10t + 7 (t ≥ 0 is integer) and n2 = q2+1 5. As a result, families of new asymmetric quantum codes [[n,k,dz/dx

Simulation of ICD-9 to ICD-10-CM transition for family medicine: simple or convoluted?

PubMed Central

Grief, Samuel N.; Patel, Jesal; Lussier, Yves A.; Li, Jianrong; Burton, Michael; Boyd, Andrew D.

2017-01-01

Objectives The objective of this study was to examine the impact of the transition from International Classification of Disease Version Nine Clinical Modification (ICD-9-CM) to Interactional Classification of Disease Version Ten Clinical Modification (ICD-10-CM) on family medicine and identify areas where additional training might be required. Methods Family medicine ICD-9-CM codes were obtained from an Illinois Medicaid data set (113,000 patient visits and $5.5 million dollars in claims). Using the science of networks we evaluated each ICD-9-CM code used by family medicine physicians to determine if the transition was simple or convoluted.1 A simple translation is defined as one ICD-9-CM code mapping to one ICD-10-CM code or one ICD-9-CM code mapping to multiple ICD-10-CM codes. A convoluted transition is where the transitions between coding systems is non-reciprocal and complex with multiple codes where definitions become intertwined. Three family medicine physicians evaluated the most frequently encountered complex mappings for clinical accuracy. Results Of the 1635 diagnosis codes used by the family medicine physicians, 70% of the codes were categorized as simple, 27% of the diagnosis codes were convoluted and 3% were found to have no mapping. For the visits, 75%, 24%, and 1% corresponded with simple, convoluted, and no mapping, respectively. Payment for submitted claims were similarly aligned. Of the frequently encountered convoluted codes, 3 diagnosis codes were clinically incorrect, but they represent only < 0.1% of the overall diagnosis codes. Conclusions The transition to ICD-10-CM is simple for 70% or more of diagnosis codes, visits, and reimbursement for a family medicine physician. However, some frequently used codes for disease management are convoluted and incorrect, where additional resources need to be invested to ensure a successful transition to ICD-10-CM. PMID:26769875

Multispectral Image Compression Based on DSC Combined with CCSDS-IDC

PubMed Central

Li, Jin; Xing, Fei; Sun, Ting; You, Zheng

2014-01-01

Remote sensing multispectral image compression encoder requires low complexity, high robust, and high performance because it usually works on the satellite where the resources, such as power, memory, and processing capacity, are limited. For multispectral images, the compression algorithms based on 3D transform (like 3D DWT, 3D DCT) are too complex to be implemented in space mission. In this paper, we proposed a compression algorithm based on distributed source coding (DSC) combined with image data compression (IDC) approach recommended by CCSDS for multispectral images, which has low complexity, high robust, and high performance. First, each band is sparsely represented by DWT to obtain wavelet coefficients. Then, the wavelet coefficients are encoded by bit plane encoder (BPE). Finally, the BPE is merged to the DSC strategy of Slepian-Wolf (SW) based on QC-LDPC by deep coupling way to remove the residual redundancy between the adjacent bands. A series of multispectral images is used to test our algorithm. Experimental results show that the proposed DSC combined with the CCSDS-IDC (DSC-CCSDS)-based algorithm has better compression performance than the traditional compression approaches. PMID:25110741

Continuous operation of four-state continuous-variable quantum key distribution system

NASA Astrophysics Data System (ADS)

Matsubara, Takuto; Ono, Motoharu; Oguri, Yusuke; Ichikawa, Tsubasa; Hirano, Takuya; Kasai, Kenta; Matsumoto, Ryutaroh; Tsurumaru, Toyohiro

2016-10-01

We report on the development of continuous-variable quantum key distribution (CV-QKD) system that are based on discrete quadrature amplitude modulation (QAM) and homodyne detection of coherent states of light. We use a pulsed light source whose wavelength is 1550 nm and repetition rate is 10 MHz. The CV-QKD system can continuously generate secret key which is secure against entangling cloner attack. Key generation rate is 50 kbps when the quantum channel is a 10 km optical fiber. The CV-QKD system we have developed utilizes the four-state and post-selection protocol [T. Hirano, et al., Phys. Rev. A 68, 042331 (2003).]; Alice randomly sends one of four states {|+/-α⟩,|+/-𝑖α⟩}, and Bob randomly performs x- or p- measurement by homodyne detection. A commercially available balanced receiver is used to realize shot-noise-limited pulsed homodyne detection. GPU cards are used to accelerate the software-based post-processing. We use a non-binary LDPC code for error correction (reverse reconciliation) and the Toeplitz matrix multiplication for privacy amplification.

Multispectral image compression based on DSC combined with CCSDS-IDC.

PubMed

Li, Jin; Xing, Fei; Sun, Ting; You, Zheng

2014-01-01

Remote sensing multispectral image compression encoder requires low complexity, high robust, and high performance because it usually works on the satellite where the resources, such as power, memory, and processing capacity, are limited. For multispectral images, the compression algorithms based on 3D transform (like 3D DWT, 3D DCT) are too complex to be implemented in space mission. In this paper, we proposed a compression algorithm based on distributed source coding (DSC) combined with image data compression (IDC) approach recommended by CCSDS for multispectral images, which has low complexity, high robust, and high performance. First, each band is sparsely represented by DWT to obtain wavelet coefficients. Then, the wavelet coefficients are encoded by bit plane encoder (BPE). Finally, the BPE is merged to the DSC strategy of Slepian-Wolf (SW) based on QC-LDPC by deep coupling way to remove the residual redundancy between the adjacent bands. A series of multispectral images is used to test our algorithm. Experimental results show that the proposed DSC combined with the CCSDS-IDC (DSC-CCSDS)-based algorithm has better compression performance than the traditional compression approaches.

Replacing the CCSDS Telecommand Protocol with the Next Generation Uplink (NGU)

NASA Technical Reports Server (NTRS)

Kazz, Greg J.; Greenberg, Ed; Burleigh, Scott C.

2012-01-01

The current CCSDS Telecommand (TC) Recommendations 1-3 have essentially been in use since the early 1960s. The purpose of this paper is to propose a successor protocol to TC. The current CCSDS recommendations can only accommodate telecommand rates up to approximately 1 mbit/s. However today's spacecraft are storehouses for software including software for Field Programmable Gate Arrays (FPGA) which are rapidly replacing unique hardware systems. Changes to flight software occasionally require uplinks to deliver very large volumes of data. In the opposite direction, high rate downlink missions that use acknowledged CCSDS File Delivery Protocol (CFDP)4 will increase the uplink data rate requirements. It is calculated that a 5 mbits/s downlink could saturate a 4 kbits/s uplink with CFDP downlink responses: negative acknowledgements (NAKs), FINISHs, End-of-File (EOF), Acknowledgements (ACKs). Moreover, it is anticipated that uplink rates of 10 to 20 mbits/s will be required to support manned missions. The current TC recommendations cannot meet these new demands. Specifically, they are very tightly coupled to the Bose-Chaudhuri-Hocquenghem (BCH) code in Ref. 2. This protocol requires that an uncorrectable BCH codeword delimit the TC frame and terminate the randomization process. This method greatly limits telecom performance since only the BCH code can support the protocol. More modern techniques such as the CCSDS Low Density Parity Check (LDPC)5 codes can provide a minimum performance gain of up to 6 times higher command data rates as long as sufficient power is available in the data. This paper will describe the proposed protocol format, trade-offs, and advantages offered, along with a discussion of how reliable communications takes place at higher nominal rates.

The Use of Color-Coded Genograms in Family Therapy.

ERIC Educational Resources Information Center

Lewis, Karen Gail

1989-01-01

Describes a variable color-coding system which has been added to the standard family genogram in which characteristics or issues associated with a particular presenting problem or for a particular family are arbitrarily assigned a color. Presents advantages of color-coding, followed by clinical examples. (Author/ABL)

Quantum error-correcting codes from algebraic geometry codes of Castle type

NASA Astrophysics Data System (ADS)

Munuera, Carlos; Tenório, Wanderson; Torres, Fernando

2016-10-01

We study algebraic geometry codes producing quantum error-correcting codes by the CSS construction. We pay particular attention to the family of Castle codes. We show that many of the examples known in the literature in fact belong to this family of codes. We systematize these constructions by showing the common theory that underlies all of them.

High-Throughput Bit-Serial LDPC Decoder LSI Based on Multiple-Valued Asynchronous Interleaving

NASA Astrophysics Data System (ADS)

Onizawa, Naoya; Hanyu, Takahiro; Gaudet, Vincent C.

This paper presents a high-throughput bit-serial low-density parity-check (LDPC) decoder that uses an asynchronous interleaver. Since consecutive log-likelihood message values on the interleaver are similar, node computations are continuously performed by using the most recently arrived messages without significantly affecting bit-error rate (BER) performance. In the asynchronous interleaver, each message's arrival rate is based on the delay due to the wire length, so that the decoding throughput is not restricted by the worst-case latency, which results in a higher average rate of computation. Moreover, the use of a multiple-valued data representation makes it possible to multiplex control signals and data from mutual nodes, thus minimizing the number of handshaking steps in the asynchronous interleaver and eliminating the clock signal entirely. As a result, the decoding throughput becomes 1.3 times faster than that of a bit-serial synchronous decoder under a 90nm CMOS technology, at a comparable BER.

Low-dose cardio-respiratory phase-correlated cone-beam micro-CT of small animals.

PubMed

Sawall, Stefan; Bergner, Frank; Lapp, Robert; Mronz, Markus; Karolczak, Marek; Hess, Andreas; Kachelriess, Marc

2011-03-01

Micro-CT imaging of animal hearts typically requires a double gating procedure because scans during a breath-hold are not possible due to the long scan times and the high respiratory rates, Simultaneous respiratory and cardiac gating can either be done prospectively or retrospectively. True five-dimensional information can be either retrieved with retrospective gating or with prospective gating if several prospective gates are acquired. In any case, the amount of information available to reconstruct one volume for a given respiratory and cardiac phase is orders of magnitud lower than the total amount of information acquired. For example, the reconstruction of a volume from a 10% wide respiratory and a 20% wide cardiac window uses only 2% of the data acquired. Achieving a similar image quality as a nongated scan would therefore require to increase the amount of data and thereby the dose to the animal by up to a factor of 50. To achieve the goal of low-dose phase-correlated (LDPC) imaging, the authors propose to use a highly efficient combination of slightly modified existing algorithms. In particular, the authors developed a variant of the McKinnon-Bates image reconstruction algorithm and combined it with bilateral filtering in up to five dimensions to significantly reduce image noise without impairing spatial or temporal resolution. The preliminary results indicate that the proposed LDPC reconstruction method typically reduces image noise by a factor of up to 6 (e.g., from 170 to 30 HU), while the dose values lie in a range from 60 to 500 mGy. Compared to other publications that apply 250-1800 mGy for the same task [C. T. Badea et al., "4D micro-CT of the mouse heart," Mol. Imaging 4(2), 110-116 (2005); M. Drangova et al., "Fast retrospectively gated quantitative four-dimensional (4D) cardiac micro computed tomography imaging of free-breathing mice," Invest. Radiol. 42(2), 85-94 (2007); S. H. Bartling et al., "Retrospective motion gating in small animal CT of mice and rats," Invest. Radiol. 42(10), 704-714 (2007)], the authors' LDPC approach therefore achieves a more than tenfold dose usage improvement. The LDPC reconstruction method improves phase-correlated imaging from highly undersampled data. Artifacts caused by sparse angular sampling are removed and the image noise is decreased, while spatial and temporal resolution are preserved. Thus, the administered dose per animal can be decreased allowing for long-term studies with reduced metabolic inference.

On the performance of joint iterative detection and decoding in coherent optical channels with laser frequency fluctuations

NASA Astrophysics Data System (ADS)

Castrillón, Mario A.; Morero, Damián A.; Agazzi, Oscar E.; Hueda, Mario R.

2015-08-01

The joint iterative detection and decoding (JIDD) technique has been proposed by Barbieri et al. (2007) with the objective of compensating the time-varying phase noise and constant frequency offset experienced in satellite communication systems. The application of JIDD to optical coherent receivers in the presence of laser frequency fluctuations has not been reported in prior literature. Laser frequency fluctuations are caused by mechanical vibrations, power supply noise, and other mechanisms. They significantly degrade the performance of the carrier phase estimator in high-speed intradyne coherent optical receivers. This work investigates the performance of the JIDD algorithm in multi-gigabit optical coherent receivers. We present simulation results of bit error rate (BER) for non-differential polarization division multiplexing (PDM)-16QAM modulation in a 200 Gb/s coherent optical system that includes an LDPC code with 20% overhead and net coding gain of 11.3 dB at BER = 10-15. Our study shows that JIDD with a pilot rate ⩽ 5 % compensates for both laser phase noise and laser frequency fluctuation. Furthermore, since JIDD is used with non-differential modulation formats, we find that gains in excess of 1 dB can be achieved over existing solutions based on an explicit carrier phase estimator with differential modulation. The impact of the fiber nonlinearities in dense wavelength division multiplexing (DWDM) systems is also investigated. Our results demonstrate that JIDD is an excellent candidate for application in next generation high-speed optical coherent receivers.

DVB-S2 Experiment over NASA's Space Network

NASA Technical Reports Server (NTRS)

Downey, Joseph A.; Evans, Michael A.; Tollis, Nicholas S.

2017-01-01

The commercial DVB-S2 standard was successfully demonstrated over NASAs Space Network (SN) and the Tracking Data and Relay Satellite System (TDRSS) during testing conducted September 20-22nd, 2016. This test was a joint effort between NASA Glenn Research Center (GRC) and Goddard Space Flight Center (GSFC) to evaluate the performance of DVB-S2 as an alternative to traditional NASA SN waveforms. Two distinct sets of tests were conducted: one was sourced from the Space Communication and Navigation (SCaN) Testbed, an external payload on the International Space Station, and the other was sourced from GRCs S-band ground station to emulate a Space Network user through TDRSS. In both cases, a commercial off-the-shelf (COTS) receiver made by Newtec was used to receive the signal at White Sands Complex. Using SCaN Testbed, peak data rates of 5.7 Mbps were demonstrated. Peak data rates of 33 Mbps were demonstrated over the GRC S-band ground station through a 10MHz channel over TDRSS, using 32-amplitude phase shift keying (APSK) and a rate 89 low density parity check (LDPC) code. Advanced features of the DVB-S2 standard were evaluated, including variable and adaptive coding and modulation (VCMACM), as well as an adaptive digital pre-distortion (DPD) algorithm. These features provided additional data throughput and increased link performance reliability. This testing has shown that commercial standards are a viable, low-cost alternative for future Space Network users.

Monitoring Our Own: Suggested Additions to the IAMFC Code of Ethics.

ERIC Educational Resources Information Center

Jordan, Karin

2001-01-01

Ethical standards for instructors of marriage and family counselors have not been well defined in the International Association for Marriage and Family Counselors code of ethics. This article describes some abuses of power in the instructor- student relationship and calls for the creation of a code of ethics for marriage and family counselor…

50 CFR Table 2c to Part 679 - Species Codes: FMP Forage Fish Species (all species of the following families)

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Species Codes: FMP Forage Fish Species (all species of the following families) 2c Table 2c to Part 679 Wildlife and Fisheries FISHERY...: FMP Forage Fish Species (all species of the following families) Species Description Code Bristlemouths...

50 CFR Table 2c to Part 679 - Species Codes: FMP Forage Fish Species (all species of the following families)

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Species Codes: FMP Forage Fish Species (all species of the following families) 2c Table 2c to Part 679 Wildlife and Fisheries FISHERY...: FMP Forage Fish Species (all species of the following families) Species Description Code Bristlemouths...

50 CFR Table 2c to Part 679 - Species Codes: FMP Forage Fish Species (all species of the following families)

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Species Codes: FMP Forage Fish Species (all species of the following families) 2c Table 2c to Part 679 Wildlife and Fisheries FISHERY...: FMP Forage Fish Species (all species of the following families) Species Description Code Bristlemouths...

50 CFR Table 2c to Part 679 - Species Codes: FMP Forage Fish Species (all species of the following families)

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Species Codes: FMP Forage Fish Species (all species of the following families) 2c Table 2c to Part 679 Wildlife and Fisheries FISHERY...: FMP Forage Fish Species (all species of the following families) Species Description Code Bristlemouths...

50 CFR Table 2c to Part 679 - Species Codes: FMP Forage Fish Species (all species of the following families)

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Species Codes: FMP Forage Fish Species (all species of the following families) 2c Table 2c to Part 679 Wildlife and Fisheries FISHERY...: FMP Forage Fish Species (all species of the following families) Species Description Code Bristlemouths...

The Pluralisation of Family Life: Implications for Preschool Education

ERIC Educational Resources Information Center

Šebart, Mojca Kovac; Kuhar, Roman

2017-01-01

The article takes as its starting point the public debate about the newly proposed Family Code in Slovenia in 2009. Inter alia, the Code introduced a new, inclusive definition of the family in accordance with the contemporary pluralisation of family life. This raised a number of questions about how--if at all--various families are addressed in the…

Exploring Type and Amount of Parent Talk during Individualized Family Service Plan Meetings

ERIC Educational Resources Information Center

Ridgley, Robyn; Snyder, Patricia; McWilliam, R. A.

2014-01-01

We discuss the utility of a coding system designed to evaluate the amount and type of parent talk during individualized family service plan (IFSP) meetings. The iterative processes used to develop the "Parent Communication Coding System" (PCCS) and its associated codes are described. In addition, we explored whether PCCS codes could be…

Two-Dimensional Parson's Puzzles: The Concept, Tools, and First Observations

ERIC Educational Resources Information Center

Ihantola, Petri; Karavirta, Ville

2011-01-01

Parson's programming puzzles are a family of code construction assignments where lines of code are given, and the task is to form the solution by sorting and possibly selecting the correct code lines. We introduce a novel family of Parson's puzzles where the lines of code need to be sorted in two dimensions. The vertical dimension is used to order…

5 CFR 890.1303 - Eligibility.

Code of Federal Regulations, 2013 CFR

2013-01-01

... EMPLOYEES HEALTH BENEFITS PROGRAM Department of Defense Federal Employees Health Benefits Program... Code, for self-only coverage or for self and family coverage. A self and family enrollment will include... family” in section 8901(5) of title 5, United States Code. A self and family enrollment will not cover a...

5 CFR 890.1303 - Eligibility.

Code of Federal Regulations, 2014 CFR

2014-01-01

... EMPLOYEES HEALTH BENEFITS PROGRAM Department of Defense Federal Employees Health Benefits Program... Code, for self-only coverage or for self and family coverage. A self and family enrollment will include... family” in section 8901(5) of title 5, United States Code. A self and family enrollment will not cover a...

High-Speed Large-Alphabet Quantum Key Distribution Using Photonic Integrated Circuits

DTIC Science & Technology

2014-01-28

polarizing beam splitter, TDC: time-to-digital converter. Extra&loss& photon/bin frame size QSER secure bpp ECC secure&key&rate& none& 0.0031 64 14...to-digital converter. photon/frame frame size QSER secure bpp ECC secure&key& rate& 1.3 16 9.5 % 2.9 layered LDPC 7.3&Mbps& Figure 24: Operating

Analyzing Relational Control in Family Therapy Interviews.

ERIC Educational Resources Information Center

Friedlander, Myrna L.; Heatherington, Laurie

1989-01-01

Introduces a modification of Ericson and Rogers' (1973) dyadic Relational Communication Control Coding System (RCCCS) for family contexts involving three or more persons. New coding rules were necessary because in families messages are not always reciprocal or direct. An illustrative excerpt shows the kinds of indexes provided by the system.(TE)

Barriers and perceptions regarding code status discussion with families of critically ill patients in a tertiary care hospital of a developing country: A cross-sectional study.

PubMed

Syed, Ahsan A; Almas, Aysha; Naeem, Quratulain; Malik, Umer F; Muhammad, Tariq

2017-02-01

In Asian societies including Pakistan, a complex background of illiteracy, different familial dynamics, lack of patient's autonomy, religious beliefs, and financial constraints give new dimensions to code status discussion. Barriers faced by physicians during code status discussion in these societies are largely unknown. To determine the barriers and perceptions in discussion of code status by physicians. Questionnaire-based cross-sectional study. This study was conducted in the Department of Medicine of The Aga Khan University Hospital, Karachi, Pakistan. A total of 134 physicians who had discussed at least five code statuses in their lifetime were included. A total of 77 (57.4%) physicians responded. Family-related barriers were found to be the most common barriers. They include family denial (74.0%), level of education of family (66.2%), and conflict between individual family members (66.2%). Regarding personal barriers, lack of knowledge regarding prognosis (44.1%), personal discomfort in discussing death (29.8%), and fear of legal consequences (28.5%) were the top most barriers. In hospital-related barriers, time constraint (57.1%), lack of hospital administration support (48.0%), and suboptimal nursing care after do not resuscitate (48.0%) were the most frequent. There were significant differences among opinions of trainees when compared to those of attending physicians. Family-related barriers are the most frequent roadblocks in the end-of-life care discussions for physicians in Pakistan. Strengthening communication skills of physicians and family education are the potential strategies to improve end-of-life care. Large multi-center studies are needed to better understand the barriers of code status discussion in developing countries.

Hyperbolic and semi-hyperbolic surface codes for quantum storage

NASA Astrophysics Data System (ADS)

Breuckmann, Nikolas P.; Vuillot, Christophe; Campbell, Earl; Krishna, Anirudh; Terhal, Barbara M.

2017-09-01

We show how a hyperbolic surface code could be used for overhead-efficient quantum storage. We give numerical evidence for a noise threshold of 1.3 % for the \\{4,5\\}-hyperbolic surface code in a phenomenological noise model (as compared with 2.9 % for the toric code). In this code family, parity checks are of weight 4 and 5, while each qubit participates in four different parity checks. We introduce a family of semi-hyperbolic codes that interpolate between the toric code and the \\{4,5\\}-hyperbolic surface code in terms of encoding rate and threshold. We show how these hyperbolic codes outperform the toric code in terms of qubit overhead for a target logical error probability. We show how Dehn twists and lattice code surgery can be used to read and write individual qubits to this quantum storage medium.

Nonlinear detection for a high rate extended binary phase shift keying system.

PubMed

Chen, Xian-Qing; Wu, Le-Nan

2013-03-28

The algorithm and the results of a nonlinear detector using a machine learning technique called support vector machine (SVM) on an efficient modulation system with high data rate and low energy consumption is presented in this paper. Simulation results showed that the performance achieved by the SVM detector is comparable to that of a conventional threshold decision (TD) detector. The two detectors detect the received signals together with the special impacting filter (SIF) that can improve the energy utilization efficiency. However, unlike the TD detector, the SVM detector concentrates not only on reducing the BER of the detector, but also on providing accurate posterior probability estimates (PPEs), which can be used as soft-inputs of the LDPC decoder. The complexity of this detector is considered in this paper by using four features and simplifying the decision function. In addition, a bandwidth efficient transmission is analyzed with both SVM and TD detector. The SVM detector is more robust to sampling rate than TD detector. We find that the SVM is suitable for extended binary phase shift keying (EBPSK) signal detection and can provide accurate posterior probability for LDPC decoding.

Nonlinear Detection for a High Rate Extended Binary Phase Shift Keying System

PubMed Central

Chen, Xian-Qing; Wu, Le-Nan

2013-01-01

The algorithm and the results of a nonlinear detector using a machine learning technique called support vector machine (SVM) on an efficient modulation system with high data rate and low energy consumption is presented in this paper. Simulation results showed that the performance achieved by the SVM detector is comparable to that of a conventional threshold decision (TD) detector. The two detectors detect the received signals together with the special impacting filter (SIF) that can improve the energy utilization efficiency. However, unlike the TD detector, the SVM detector concentrates not only on reducing the BER of the detector, but also on providing accurate posterior probability estimates (PPEs), which can be used as soft-inputs of the LDPC decoder. The complexity of this detector is considered in this paper by using four features and simplifying the decision function. In addition, a bandwidth efficient transmission is analyzed with both SVM and TD detector. The SVM detector is more robust to sampling rate than TD detector. We find that the SVM is suitable for extended binary phase shift keying (EBPSK) signal detection and can provide accurate posterior probability for LDPC decoding. PMID:23539034

Spinstand demonstration of areal density enhancement using two-dimensional magnetic recording (invited)

NASA Astrophysics Data System (ADS)

Lippman, Thomas; Brockie, Richard; Coker, Jon; Contreras, John; Galbraith, Rick; Garzon, Samir; Hanson, Weldon; Leong, Tom; Marley, Arley; Wood, Roger; Zakai, Rehan; Zolla, Howard; Duquette, Paul; Petrizzi, Joe

2015-05-01

Exponential growth of the areal density has driven the magnetic recording industry for almost sixty years. But now areal density growth is slowing down, suggesting that current technologies are reaching their fundamental limit. The next generation of recording technologies, namely, energy-assisted writing and bit-patterned media, remains just over the horizon. Two-Dimensional Magnetic Recording (TDMR) is a promising new approach, enabling continued areal density growth with only modest changes to the heads and recording electronics. We demonstrate a first generation implementation of TDMR by using a dual-element read sensor to improve the recovery of data encoded by a conventional low-density parity-check (LDPC) channel. The signals are combined with a 2D equalizer into a single modified waveform that is decoded by a standard LDPC channel. Our detection hardware can perform simultaneous measurement of the pre- and post-combined error rate information, allowing one set of measurements to assess the absolute areal density capability of the TDMR system as well as the gain over a conventional shingled magnetic recording system with identical components. We discuss areal density measurements using this hardware and demonstrate gains exceeding five percent based on experimental dual reader components.

Whole-genome sequencing reveals a coding non-pathogenic variant tagging a non-coding pathogenic hexanucleotide repeat expansion in C9orf72 as cause of amyotrophic lateral sclerosis.

PubMed

Herdewyn, Sarah; Zhao, Hui; Moisse, Matthieu; Race, Valérie; Matthijs, Gert; Reumers, Joke; Kusters, Benno; Schelhaas, Helenius J; van den Berg, Leonard H; Goris, An; Robberecht, Wim; Lambrechts, Diether; Van Damme, Philip

2012-06-01

Motor neuron degeneration in amyotrophic lateral sclerosis (ALS) has a familial cause in 10% of patients. Despite significant advances in the genetics of the disease, many families remain unexplained. We performed whole-genome sequencing in five family members from a pedigree with autosomal-dominant classical ALS. A family-based elimination approach was used to identify novel coding variants segregating with the disease. This list of variants was effectively shortened by genotyping these variants in 2 additional unaffected family members and 1500 unrelated population-specific controls. A novel rare coding variant in SPAG8 on chromosome 9p13.3 segregated with the disease and was not observed in controls. Mutations in SPAG8 were not encountered in 34 other unexplained ALS pedigrees, including 1 with linkage to chromosome 9p13.2-23.3. The shared haplotype containing the SPAG8 variant in this small pedigree was 22.7 Mb and overlapped with the core 9p21 linkage locus for ALS and frontotemporal dementia. Based on differences in coverage depth of known variable tandem repeat regions between affected and non-affected family members, the shared haplotype was found to contain an expanded hexanucleotide (GGGGCC)(n) repeat in C9orf72 in the affected members. Our results demonstrate that rare coding variants identified by whole-genome sequencing can tag a shared haplotype containing a non-coding pathogenic mutation and that changes in coverage depth can be used to reveal tandem repeat expansions. It also confirms (GGGGCC)n repeat expansions in C9orf72 as a cause of familial ALS.

Construction of self-dual codes in the Rosenbloom-Tsfasman metric

NASA Astrophysics Data System (ADS)

Krisnawati, Vira Hari; Nisa, Anzi Lina Ukhtin

2017-12-01

Linear code is a very basic code and very useful in coding theory. Generally, linear code is a code over finite field in Hamming metric. Among the most interesting families of codes, the family of self-dual code is a very important one, because it is the best known error-correcting code. The concept of Hamming metric is develop into Rosenbloom-Tsfasman metric (RT-metric). The inner product in RT-metric is different from Euclid inner product that is used to define duality in Hamming metric. Most of the codes which are self-dual in Hamming metric are not so in RT-metric. And, generator matrix is very important to construct a code because it contains basis of the code. Therefore in this paper, we give some theorems and methods to construct self-dual codes in RT-metric by considering properties of the inner product and generator matrix. Also, we illustrate some examples for every kind of the construction.

Sequence-based heuristics for faster annotation of non-coding RNA families.

PubMed

Weinberg, Zasha; Ruzzo, Walter L

2006-01-01

Non-coding RNAs (ncRNAs) are functional RNA molecules that do not code for proteins. Covariance Models (CMs) are a useful statistical tool to find new members of an ncRNA gene family in a large genome database, using both sequence and, importantly, RNA secondary structure information. Unfortunately, CM searches are extremely slow. Previously, we created rigorous filters, which provably sacrifice none of a CM's accuracy, while making searches significantly faster for virtually all ncRNA families. However, these rigorous filters make searches slower than heuristics could be. In this paper we introduce profile HMM-based heuristic filters. We show that their accuracy is usually superior to heuristics based on BLAST. Moreover, we compared our heuristics with those used in tRNAscan-SE, whose heuristics incorporate a significant amount of work specific to tRNAs, where our heuristics are generic to any ncRNA. Performance was roughly comparable, so we expect that our heuristics provide a high-quality solution that--unlike family-specific solutions--can scale to hundreds of ncRNA families. The source code is available under GNU Public License at the supplementary web site.

A high throughput architecture for a low complexity soft-output demapping algorithm

NASA Astrophysics Data System (ADS)

Ali, I.; Wasenmüller, U.; Wehn, N.

2015-11-01

Iterative channel decoders such as Turbo-Code and LDPC decoders show exceptional performance and therefore they are a part of many wireless communication receivers nowadays. These decoders require a soft input, i.e., the logarithmic likelihood ratio (LLR) of the received bits with a typical quantization of 4 to 6 bits. For computing the LLR values from a received complex symbol, a soft demapper is employed in the receiver. The implementation cost of traditional soft-output demapping methods is relatively large in high order modulation systems, and therefore low complexity demapping algorithms are indispensable in low power receivers. In the presence of multiple wireless communication standards where each standard defines multiple modulation schemes, there is a need to have an efficient demapper architecture covering all the flexibility requirements of these standards. Another challenge associated with hardware implementation of the demapper is to achieve a very high throughput in double iterative systems, for instance, MIMO and Code-Aided Synchronization. In this paper, we present a comprehensive communication and hardware performance evaluation of low complexity soft-output demapping algorithms to select the best algorithm for implementation. The main goal of this work is to design a high throughput, flexible, and area efficient architecture. We describe architectures to execute the investigated algorithms. We implement these architectures on a FPGA device to evaluate their hardware performance. The work has resulted in a hardware architecture based on the figured out best low complexity algorithm delivering a high throughput of 166 Msymbols/second for Gray mapped 16-QAM modulation on Virtex-5. This efficient architecture occupies only 127 slice registers, 248 slice LUTs and 2 DSP48Es.

NASA Tech Briefs, September 2009

NASA Technical Reports Server (NTRS)

2009-01-01

opics covered include: Filtering Water by Use of Ultrasonically Vibrated Nanotubes; Computer Code for Nanostructure Simulation; Functionalizing CNTs for Making Epoxy/CNT Composites; Improvements in Production of Single-Walled Carbon Nanotubes; Progress Toward Sequestering Carbon Nanotubes in PmPV; Two-Stage Variable Sample-Rate Conversion System; Estimating Transmitted-Signal Phase Variations for Uplink Array Antennas; Board Saver for Use with Developmental FPGAs; Circuit for Driving Piezoelectric Transducers; Digital Synchronizer without Metastability; Compact, Low-Overhead, MIL-STD-1553B Controller; Parallel-Processing CMOS Circuitry for M-QAM and 8PSK TCM; Differential InP HEMT MMIC Amplifiers Embedded in Waveguides; Improved Aerogel Vacuum Thermal Insulation; Fluoroester Co-Solvents for Low-Temperature Li+ Cells; Using Volcanic Ash to Remove Dissolved Uranium and Lead; High-Efficiency Artificial Photosynthesis Using a Novel Alkaline Membrane Cell; Silicon Wafer-Scale Substrate for Microshutters and Detector Arrays; Micro-Horn Arrays for Ultrasonic Impedance Matching; Improved Controller for a Three-Axis Piezoelectric Stage; Nano-Pervaporation Membrane with Heat Exchanger Generates Medical-Grade Water; Micro-Organ Devices; Nonlinear Thermal Compensators for WGM Resonators; Dynamic Self-Locking of an OEO Containing a VCSEL; Internal Water Vapor Photoacoustic Calibration; Mid-Infrared Reflectance Imaging of Thermal-Barrier Coatings; Improving the Visible and Infrared Contrast Ratio of Microshutter Arrays; Improved Scanners for Microscopic Hyperspectral Imaging; Rate-Compatible LDPC Codes with Linear Minimum Distance; PrimeSupplier Cross-Program Impact Analysis and Supplier Stability Indicator Simulation Model; Integrated Planning for Telepresence With Time Delays; Minimizing Input-to-Output Latency in Virtual Environment; Battery Cell Voltage Sensing and Balancing Using Addressable Transformers; Gaussian and Lognormal Models of Hurricane Gust Factors; Simulation of Attitude and Trajectory Dynamics and Control of Multiple Spacecraft; Integrated Modeling of Spacecraft Touch-and-Go Sampling; Spacecraft Station-Keeping Trajectory and Mission Design Tools; Efficient Model-Based Diagnosis Engine; and DSN Simulator.

Image transmission system using adaptive joint source and channel decoding

NASA Astrophysics Data System (ADS)

Liu, Weiliang; Daut, David G.

2005-03-01

In this paper, an adaptive joint source and channel decoding method is designed to accelerate the convergence of the iterative log-dimain sum-product decoding procedure of LDPC codes as well as to improve the reconstructed image quality. Error resilience modes are used in the JPEG2000 source codec, which makes it possible to provide useful source decoded information to the channel decoder. After each iteration, a tentative decoding is made and the channel decoded bits are then sent to the JPEG2000 decoder. Due to the error resilience modes, some bits are known to be either correct or in error. The positions of these bits are then fed back to the channel decoder. The log-likelihood ratios (LLR) of these bits are then modified by a weighting factor for the next iteration. By observing the statistics of the decoding procedure, the weighting factor is designed as a function of the channel condition. That is, for lower channel SNR, a larger factor is assigned, and vice versa. Results show that the proposed joint decoding methods can greatly reduce the number of iterations, and thereby reduce the decoding delay considerably. At the same time, this method always outperforms the non-source controlled decoding method up to 5dB in terms of PSNR for various reconstructed images.

The search for person-related information in general practice: a qualitative study.

PubMed

Schrans, Diego; Avonts, Dirk; Christiaens, Thierry; Willems, Sara; de Smet, Kaat; van Boven, Kees; Boeckxstaens, Pauline; Kühlein, Thomas

2016-02-01

General practice is person-focused. Contextual information influences the clinical decision-making process in primary care. Currently, person-related information (PeRI) is neither recorded in a systematic way nor coded in the electronic medical record (EMR), and therefore not usable for scientific use. To search for classes of PeRI influencing the process of care. GPs, from nine countries worldwide, were asked to write down narrative case histories where personal factors played a role in decision-making. In an inductive process, the case histories were consecutively coded according to classes of PeRI. The classes found were deductively applied to the following cases and refined, until saturation was reached. Then, the classes were grouped into code-families and further clustered into domains. The inductive analysis of 32 case histories resulted in 33 defined PeRI codes, classifying all personal-related information in the cases. The 33 codes were grouped in the following seven mutually exclusive code-families: 'aspects between patient and formal care provider', 'social environment and family', 'functioning/behaviour', 'life history/non-medical experiences', 'personal medical information', 'socio-demographics' and 'work-/employment-related information'. The code-families were clustered into four domains: 'social environment and extended family', 'medicine', 'individual' and 'work and employment'. As PeRI is used in the process of decision-making, it should be part of the EMR. The PeRI classes we identified might form the basis of a new contextual classification mainly for research purposes. This might help to create evidence of the person-centredness of general practice. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Conserved expression of transposon-derived non-coding transcripts in primate stem cells.

PubMed

Ramsay, LeeAnn; Marchetto, Maria C; Caron, Maxime; Chen, Shu-Huang; Busche, Stephan; Kwan, Tony; Pastinen, Tomi; Gage, Fred H; Bourque, Guillaume

2017-02-28

A significant portion of expressed non-coding RNAs in human cells is derived from transposable elements (TEs). Moreover, it has been shown that various long non-coding RNAs (lncRNAs), which come from the human endogenous retrovirus subfamily H (HERVH), are not only expressed but required for pluripotency in human embryonic stem cells (hESCs). To identify additional TE-derived functional non-coding transcripts, we generated RNA-seq data from induced pluripotent stem cells (iPSCs) of four primate species (human, chimpanzee, gorilla, and rhesus) and searched for transcripts whose expression was conserved. We observed that about 30% of TE instances expressed in human iPSCs had orthologous TE instances that were also expressed in chimpanzee and gorilla. Notably, our analysis revealed a number of repeat families with highly conserved expression profiles including HERVH but also MER53, which is known to be the source of a placental-specific family of microRNAs (miRNAs). We also identified a number of repeat families from all classes of TEs, including MLT1-type and Tigger families, that contributed a significant amount of sequence to primate lncRNAs whose expression was conserved. Together, these results describe TE families and TE-derived lncRNAs whose conserved expression patterns can be used to identify what are likely functional TE-derived non-coding transcripts in primate iPSCs.

Transcriptome Analysis of Scorpion Species Belonging to the Vaejovis Genus

PubMed Central

Quintero-Hernández, Verónica; Ramírez-Carreto, Santos; Romero-Gutiérrez, María Teresa; Valdez-Velázquez, Laura L.; Becerril, Baltazar; Possani, Lourival D.; Ortiz, Ernesto

2015-01-01

Scorpions belonging to the Buthidae family have traditionally drawn much of the biochemist’s attention due to the strong toxicity of their venoms. Scorpions not toxic to mammals, however, also have complex venoms. They have been shown to be an important source of bioactive peptides, some of them identified as potential drug candidates for the treatment of several emerging diseases and conditions. It is therefore important to characterize the large diversity of components found in the non-Buthidae venoms. As a contribution to this goal, this manuscript reports the construction and characterization of cDNA libraries from four scorpion species belonging to the Vaejovis genus of the Vaejovidae family: Vaejovis mexicanus, V. intrepidus, V. subcristatus and V. punctatus. Some sequences coding for channel-acting toxins were found, as expected, but the main transcribed genes in the glands actively producing venom were those coding for non disulfide-bridged peptides. The ESTs coding for putative channel-acting toxins, corresponded to sodium channel β toxins, to members of the potassium channel-acting α or κ families, and to calcium channel-acting toxins of the calcin family. Transcripts for scorpine-like peptides of two different lengths were found, with some of the species coding for the two kinds. One sequence coding for La1-like peptides, of yet unknown function, was found for each species. Finally, the most abundant transcripts corresponded to peptides belonging to the long chain multifunctional NDBP-2 family and to the short antimicrobials of the NDBP-4 family. This apparent venom composition is in correspondence with the data obtained to date for other non-Buthidae species. Our study constitutes the first approach to the characterization of the venom gland transcriptome for scorpion species belonging to the Vaejovidae family. PMID:25659089

Transcriptome analysis of scorpion species belonging to the Vaejovis genus.

PubMed

Quintero-Hernández, Verónica; Ramírez-Carreto, Santos; Romero-Gutiérrez, María Teresa; Valdez-Velázquez, Laura L; Becerril, Baltazar; Possani, Lourival D; Ortiz, Ernesto

2015-01-01

Scorpions belonging to the Buthidae family have traditionally drawn much of the biochemist's attention due to the strong toxicity of their venoms. Scorpions not toxic to mammals, however, also have complex venoms. They have been shown to be an important source of bioactive peptides, some of them identified as potential drug candidates for the treatment of several emerging diseases and conditions. It is therefore important to characterize the large diversity of components found in the non-Buthidae venoms. As a contribution to this goal, this manuscript reports the construction and characterization of cDNA libraries from four scorpion species belonging to the Vaejovis genus of the Vaejovidae family: Vaejovis mexicanus, V. intrepidus, V. subcristatus and V. punctatus. Some sequences coding for channel-acting toxins were found, as expected, but the main transcribed genes in the glands actively producing venom were those coding for non disulfide-bridged peptides. The ESTs coding for putative channel-acting toxins, corresponded to sodium channel β toxins, to members of the potassium channel-acting α or κ families, and to calcium channel-acting toxins of the calcin family. Transcripts for scorpine-like peptides of two different lengths were found, with some of the species coding for the two kinds. One sequence coding for La1-like peptides, of yet unknown function, was found for each species. Finally, the most abundant transcripts corresponded to peptides belonging to the long chain multifunctional NDBP-2 family and to the short antimicrobials of the NDBP-4 family. This apparent venom composition is in correspondence with the data obtained to date for other non-Buthidae species. Our study constitutes the first approach to the characterization of the venom gland transcriptome for scorpion species belonging to the Vaejovidae family.

12 CFR 1807.503 - Project completion.

Code of Federal Regulations, 2012 CFR

2012-01-01

... applicable: One of three model codes (Uniform Building Code (ICBO), National Building Code (BOCA), Standard (Southern) Building Code (SBCCI)); or the Council of American Building Officials (CABO) one or two family... must meet the current edition of the Model Energy Code published by the Council of American Building...

12 CFR 1807.503 - Project completion.

Code of Federal Regulations, 2013 CFR

2013-01-01

... applicable: One of three model codes (Uniform Building Code (ICBO), National Building Code (BOCA), Standard (Southern) Building Code (SBCCI)); or the Council of American Building Officials (CABO) one or two family... must meet the current edition of the Model Energy Code published by the Council of American Building...

12 CFR 1807.503 - Project completion.

Code of Federal Regulations, 2014 CFR

2014-01-01

... applicable: One of three model codes (Uniform Building Code (ICBO), National Building Code (BOCA), Standard (Southern) Building Code (SBCCI)); or the Council of American Building Officials (CABO) one or two family... must meet the current edition of the Model Energy Code published by the Council of American Building...

12 CFR 1807.503 - Project completion.

Code of Federal Regulations, 2011 CFR

2011-01-01

... applicable: One of three model codes (Uniform Building Code (ICBO), National Building Code (BOCA), Standard (Southern) Building Code (SBCCI)); or the Council of American Building Officials (CABO) one or two family... must meet the current edition of the Model Energy Code published by the Council of American Building...

Finding your way through EOL challenges in the ICU using Adaptive Leadership behaviours: A qualitative descriptive case study.

PubMed

Adams, Judith A; Bailey, Donald E; Anderson, Ruth A; Thygeson, Marcus

2013-12-01

Using the Adaptive Leadership framework, we describe behaviours that providers used while interacting with family members facing the challenges of recognising that their loved one was dying in the ICU. In this prospective pilot case study, we selected one ICU patient with end-stage illness who lacked decision-making capacity. Participants included four family members, one nurse and two physicians. The principle investigator observed and recorded three family conferences and conducted one in-depth interview with the family. Three members of the research team independently coded the transcripts using a priori codes to describe the Adaptive Leadership behaviours that providers used to facilitate the family's adaptive work, met to compare and discuss the codes and resolved all discrepancies. We identified behaviours used by nurses and physicians that facilitated the family's ability to adapt to the impending death of a loved one. Examples of these behaviours include defining the adaptive challenges for families and foreshadowing a poor prognosis. Nurse and physician Adaptive Leadership behaviours can facilitate the transition from curative to palliative care by helping family members do the adaptive work of letting go. Further research is warranted to create knowledge for providers to help family members adapt. Copyright © 2013 Elsevier Ltd. All rights reserved.

Diabetes Mellitus Coding Training for Family Practice Residents.

PubMed

Urse, Geraldine N

2015-07-01

Although physicians regularly use numeric coding systems such as the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) to describe patient encounters, coding errors are common. One of the most complicated diagnoses to code is diabetes mellitus. The ICD-9-CM currently has 39 separate codes for diabetes mellitus; this number will be expanded to more than 50 with the introduction of ICD-10-CM in October 2015. To assess the effect of a 1-hour focused presentation on ICD-9-CM codes on diabetes mellitus coding. A 1-hour focused lecture on the correct use of diabetes mellitus codes for patient visits was presented to family practice residents at Doctors Hospital Family Practice in Columbus, Ohio. To assess resident knowledge of the topic, a pretest and posttest were given to residents before and after the lecture, respectively. Medical records of all patients with diabetes mellitus who were cared for at the hospital 6 weeks before and 6 weeks after the lecture were reviewed and compared for the use of diabetes mellitus ICD-9 codes. Eighteen residents attended the lecture and completed the pretest and posttest. The mean (SD) percentage of correct answers was 72.8% (17.1%) for the pretest and 84.4% (14.6%) for the posttest, for an improvement of 11.6 percentage points (P≤.035). The percentage of total available codes used did not substantially change from before to after the lecture, but the use of the generic ICD-9-CM code for diabetes mellitus type II controlled (250.00) declined (58 of 176 [33%] to 102 of 393 [26%]) and the use of other codes increased, indicating a greater variety in codes used after the focused lecture. After a focused lecture on diabetes mellitus coding, resident coding knowledge improved. Review of medical record data did not reveal an overall change in the number of diabetic codes used after the lecture but did reveal a greater variety in the codes used.

Use of the Family Interaction Macro-coding System with Families of Adolescents: Psychometric Properties Among Pediatric and Healthy Populations

PubMed Central

Zebracki, Kathy; Kichler, Jessica C.; Fitzgerald, Christopher J.; Neff Greenley, Rachel; Alemzadeh, Ramin; Holmbeck, Grayson N.

2011-01-01

Objective To examine reliability and validity data for the Family Interaction Macro-coding System (FIMS) with adolescents with spina bifida (SB), adolescents with type 1 diabetes mellitus (T1DM), and healthy adolescents and their families. Methods Sixty-eight families of children with SB, 58 families of adolescents with T1DM, and 68 families in a healthy comparison group completed family interaction tasks and self-report questionnaires. Trained coders rated family interactions using the FIMS. Results Acceptable interrater and scale reliabilities were obtained for FIMS items and subscales. Observed FIMS parental acceptance, parental behavioral control, parental psychological control, family cohesion, and family conflict scores demonstrated convergent validity with conceptually similar self-report measures. Conclusions Preliminary evidence supports the use of the FIMS with families of youths with SB and T1DM and healthy youths. Future research on overall family functioning may be enhanced by use of the FIMS. PMID:21097956

A family of chaotic pure analog coding schemes based on baker's map function

NASA Astrophysics Data System (ADS)

Liu, Yang; Li, Jing; Lu, Xuanxuan; Yuen, Chau; Wu, Jun

2015-12-01

This paper considers a family of pure analog coding schemes constructed from dynamic systems which are governed by chaotic functions—baker's map function and its variants. Various decoding methods, including maximum likelihood (ML), minimum mean square error (MMSE), and mixed ML-MMSE decoding algorithms, have been developed for these novel encoding schemes. The proposed mirrored baker's and single-input baker's analog codes perform a balanced protection against the fold error (large distortion) and weak distortion and outperform the classical chaotic analog coding and analog joint source-channel coding schemes in literature. Compared to the conventional digital communication system, where quantization and digital error correction codes are used, the proposed analog coding system has graceful performance evolution, low decoding latency, and no quantization noise. Numerical results show that under the same bandwidth expansion, the proposed analog system outperforms the digital ones over a wide signal-to-noise (SNR) range.

Rate-compatible punctured convolutional codes (RCPC codes) and their applications

NASA Astrophysics Data System (ADS)

Hagenauer, Joachim

1988-04-01

The concept of punctured convolutional codes is extended by punctuating a low-rate 1/N code periodically with period P to obtain a family of codes with rate P/(P + l), where l can be varied between 1 and (N - 1)P. A rate-compatibility restriction on the puncturing tables ensures that all code bits of high rate codes are used by the lower-rate codes. This allows transmission of incremental redundancy in ARQ/FEC (automatic repeat request/forward error correction) schemes and continuous rate variation to change from low to high error protection within a data frame. Families of RCPC codes with rates between 8/9 and 1/4 are given for memories M from 3 to 6 (8 to 64 trellis states) together with the relevant distance spectra. These codes are almost as good as the best known general convolutional codes of the respective rates. It is shown that the same Viterbi decoder can be used for all RCPC codes of the same M. The application of RCPC codes to hybrid ARQ/FEC schemes is discussed for Gaussian and Rayleigh fading channels using channel-state information to optimize throughput.

Conveying empathy to hospice family caregivers: Team responses to caregiver empathic communication

PubMed Central

Wittenberg-Lyles, Elaine; Oliver, Debra Parker; Demiris, George; Rankin, Anna; Shaunfield, Sara; Kruse, Robin L.

2012-01-01

Objective The goal of this study was to explore empathic communication opportunities presented by family caregivers and responses from interdisciplinary hospice team members. Methods Empathic opportunities and hospice team responses were analyzed from biweekly web-based videoconferences between family caregivers and hospice teams. The authors coded the data using the Empathic Communication Coding System (ECCS) and identified themes within and among the coded data. Results Data analysis identified 270 empathic opportunity-team response sequences. Caregivers expressed statements of emotion and decline most frequently. Two-thirds of the hospice team responses were implicit acknowledgments of caregiver statements and only one-third of the team responses were explicit recognitions of caregiver empathic opportunities. Conclusion Although hospice team members frequently express emotional concerns with family caregivers during one-on-one visits, there is a need for more empathic communication during team meetings that involve caregivers. Practice implications Hospice clinicians should devote more time to discussing emotional issues with patients and their families to enhance patient-centered hospice care. Further consideration should be given to training clinicians to empathize with patients and family caregivers. PMID:22554387

Conveying empathy to hospice family caregivers: team responses to caregiver empathic communication.

PubMed

Wittenberg-Lyles, Elaine; Debra, Parker Oliver; Demiris, George; Rankin, Anna; Shaunfield, Sara; Kruse, Robin L

2012-10-01

The goal of this study was to explore empathic communication opportunities presented by family caregivers and responses from interdisciplinary hospice team members. Empathic opportunities and hospice team responses were analyzed from bi-weekly web-based videoconferences between family caregivers and hospice teams. The authors coded the data using the Empathic Communication Coding System (ECCS) and identified themes within and among the coded data. Data analysis identified 270 empathic opportunity-team response sequences. Caregivers expressed statements of emotion and decline most frequently. Two-thirds of the hospice team responses were implicit acknowledgements of caregiver statements and only one-third of the team responses were explicit recognitions of caregiver empathic opportunities. Although hospice team members frequently express emotional concerns with family caregivers during one-on-one visits, there is a need for more empathic communication during team meetings that involve caregivers. Hospice clinicians should devote more time to discussing emotional issues with patients and their families to enhance patient-centered hospice care. Further consideration should be given to training clinicians to empathize with patients and family caregivers. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Surgeon General's Family Health History Initiative

MedlinePlus

... Source Code The Surgeon General's Family Health History Initiative To help focus attention on the importance of ... health campaign, called the Surgeon General's Family History Initiative, to encourage all American families to learn more ...

How families cope with diabetes in adolescence. An approach and case analyses.

PubMed

Hauser, S T; Paul, E L; Jacobson, A M; Weiss-Perry, B; Vieyra, M A; Rufo, P; Spetter, L D; DiPlacido, J; Wertlieb, D; Wolfsdorf, J

1988-01-01

In this paper we describe our newly constructed Family Coping Coding System. This scheme was constructed to identify family coping strategies that involve appraisal, problem solving, and emotion management dimensions. We discuss the theoretical rationale, meanings and reliability of the coping codes, and illustrate them through excerpts drawn from family discussions of a recent stressful situation (the onset of a chronic or acute illness in an adolescent member). Finally, we consider the clinical research relevance of this new assessment technique, exemplifying this potential with respect to medical compliance. We present analyses of two families with diabetic adolescents who strikingly differ with respect to compliance, and explore which family coping strategies may be predictive of an adolescent's favorable or problematic compliance to diabetes management.

Novel variants of the 5S rRNA genes in Eruca sativa.

PubMed

Singh, K; Bhatia, S; Lakshmikumaran, M

1994-02-01

The 5S ribosomal RNA (rRNA) genes of Eruca sativa were cloned and characterized. They are organized into clusters of tandemly repeated units. Each repeat unit consists of a 119-bp coding region followed by a noncoding spacer region that separates it from the coding region of the next repeat unit. Our study reports novel gene variants of the 5S rRNA genes in plants. Two families of the 5S rDNA, the 0.5-kb size family and the 1-kb size family, coexist in the E. sativa genome. The 0.5-kb size family consists of the 5S rRNA genes (S4) that have coding regions similar to those of other reported plant 5S rDNA sequences, whereas the 1-kb size family consists of the 5S rRNA gene variants (S1) that exist as 1-kb BamHI tandem repeats. S1 is made up of two variant units (V1 and V2) of 5S rDNA where the BamHI site between the two units is mutated. Sequence heterogeneity among S4, V1, and V2 units exists throughout the sequence and is not limited to the noncoding spacer region only. The coding regions of V1 and V2 show approximately 20% dissimilarity to the coding regions of S4 and other reported plant 5S rDNA sequences. Such a large variation in the coding regions of the 5S rDNA units within the same plant species has been observed for the first time. Restriction site variation is observed between the two size classes of 5S rDNA in E. sativa.(ABSTRACT TRUNCATED AT 250 WORDS)

A Case Study of Childhood Disintegrative Disorder Using Systematic Analysis of Family Home Movies

ERIC Educational Resources Information Center

Palomo, Ruben; Thompson, Meagan; Colombi, Costanza; Cook, Ian; Goldring, Stacy; Young, Gregory S.; Ozonoff, Sally

2008-01-01

Childhood disintegrative disorder (CDD) is a rare pervasive developmental disorder that involves regression after a period of at least 2 years of typical development. This case study presents data from family home movies, coded by reliable raters using an objective coding system, to examine the trajectory of development in one child with a…

Perceptions of Family Among Low-Income Patients With Diabetes in a Text-Based Mobile Health Intervention.

PubMed

Burner, Elizabeth R E; Menchine, Michael D; Kubicek, Katrina; Robles, Marisela; Kagawa Singer, Marjorie; Arora, Sanjay

2018-04-01

Diabetes disproportionately affects the US Latino population, due to socioeconomic pressures, genetics, reduced access to care and cultural practices. While efforts to improve self-care through interventions incorporating family are highly rated by Latinos, family can be both supportive and obstructive. To develop effective interventions, this role needs clarification. We conducted group interviews in Spanish and English with 24 participants with diabetes from a mobile health diabetes self-care intervention. We imported transcripts into Dedoose, a qualitative computer analysis program and analyzed them with a modified grounded theory technique. Utilizing an iterative process, we reexamined transcripts with new codes derived in each round of analysis until saturation was reached. We employed techniques to improve trustworthiness (co-coding, member checking). Broad categorical themes arose from the initial codes and were developed into a conceptual model of barriers to and strategies for diabetes management. Family and family responsibilities emerged as both a supportive and obstructive force for diabetes self-care. While the desire to care for family motivated patients, food at family gatherings and pressure from managing multiple family responsibilities contributed to poor diet choices. Yet, some patients believed their diabetes caused their immediate family to make healthier choices. Among these predominantly Latino patients, family and family responsibilities were key motivators as well as obstacles to self-care, particularly regarding nutrition. Finding the ideal design for social support mHealth-based interventions will require careful study and creation of culturally based programs to match the needs of specific populations, and may require educating family members to provide effective social support.

Impact of the Primary Care Exception on Family Medicine Resident Coding.

PubMed

Cawse-Lucas, Jeanne; Evans, David V; Ruiz, David R; Allcut, Elizabeth A; Andrilla, C Holly A; Thompson, Matthew; Norris, Thomas E

2016-03-01

The Medicare Primary Care Exception (PCE) allows residents to see and bill for less-complex patients independently in the primary care setting, requiring attending physicians only to see patients for higher-level visits and complete physical exams in order to bill for them as such. Primary care residencies apply the PCE in various ways. We investigated the impact of the PCE on resident coding practices. Family medicine residency directors in a five-state region completed a survey regarding interpretation and application of the PCE, including the number of established patient evaluation and management codes entered by residents and attending faculty at their institution. The percentage of high-level codes was compared between residencies using chi-square tests. We analyzed coding data for 125,016 visits from 337 residents and 172 faculty physicians in 15 of 18 eligible family medicine residencies. Among programs applying the PCE criteria to all patients, residents billed 86.7% low-mid complexity and 13.3% high-complexity visits. In programs that only applied the PCE to Medicare patients, residents billed 74.9% low-mid complexity visits and 25.2% high-complexity visits. Attending physicians coded more high-complexity visits at both types of programs. The estimated revenue loss over the 1,650 RRC-required outpatient visits was $2,558.66 per resident and $57,569.85 per year for the average residency in our sample. Residents at family medicine programs that apply the PCE to all patients bill significantly fewer high-complexity visits. This finding leads to compliance and regulatory concerns and suggests significant revenue loss. Further study is required to determine whether this discrepancy also reflects inaccuracy in coding.

10 CFR 434.99 - Explanation of numbering system for codes.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 3 2011-01-01 2011-01-01 false Explanation of numbering system for codes. 434.99 Section 434.99 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS § 434.99 Explanation of numbering system for codes. (a) For...

10 CFR 434.99 - Explanation of numbering system for codes.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Explanation of numbering system for codes. 434.99 Section 434.99 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS § 434.99 Explanation of numbering system for codes. (a) For...

On entanglement-assisted quantum codes achieving the entanglement-assisted Griesmer bound

NASA Astrophysics Data System (ADS)

Li, Ruihu; Li, Xueliang; Guo, Luobin

2015-12-01

The theory of entanglement-assisted quantum error-correcting codes (EAQECCs) is a generalization of the standard stabilizer formalism. Any quaternary (or binary) linear code can be used to construct EAQECCs under the entanglement-assisted (EA) formalism. We derive an EA-Griesmer bound for linear EAQECCs, which is a quantum analog of the Griesmer bound for classical codes. This EA-Griesmer bound is tighter than known bounds for EAQECCs in the literature. For a given quaternary linear code {C}, we show that the parameters of the EAQECC that EA-stabilized by the dual of {C} can be determined by a zero radical quaternary code induced from {C}, and a necessary condition under which a linear EAQECC may achieve the EA-Griesmer bound is also presented. We construct four families of optimal EAQECCs and then show the necessary condition for existence of EAQECCs is also sufficient for some low-dimensional linear EAQECCs. The four families of optimal EAQECCs are degenerate codes and go beyond earlier constructions. What is more, except four codes, our [[n,k,d_{ea};c

The first mitochondrial genome for the butterfly family Riodinidae (Abisara fylloides) and its systematic implications.

PubMed

Zhao, Fang; Huang, Dun-Yuan; Sun, Xiao-Yan; Shi, Qing-Hui; Hao, Jia-Sheng; Zhang, Lan-Lan; Yang, Qun

2013-10-01

The Riodinidae is one of the lepidopteran butterfly families. This study describes the complete mitochondrial genome of the butterfly species Abisara fylloides, the first mitochondrial genome of the Riodinidae family. The results show that the entire mitochondrial genome of A. fylloides is 15 301 bp in length, and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and a 423 bp A+T-rich region. The gene content, orientation and order are identical to the majority of other lepidopteran insects. Phylogenetic reconstruction was conducted using the concatenated 13 protein-coding gene (PCG) sequences of 19 available butterfly species covering all the five butterfly families (Papilionidae, Nymphalidae, Peridae, Lycaenidae and Riodinidae). Both maximum likelihood and Bayesian inference analyses highly supported the monophyly of Lycaenidae+Riodinidae, which was standing as the sister of Nymphalidae. In addition, we propose that the riodinids be categorized into the family Lycaenidae as a subfamilial taxon. The Riodinidae is one of the lepidopteran butterfly families. This study describes the complete mitochondrial genome of the butterfly species Abisara fylloides , the first mitochondrial genome of the Riodinidae family. The results show that the entire mitochondrial genome of A. fylloides is 15 301 bp in length, and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and a 423 bp A+T-rich region. The gene content, orientation and order are identical to the majority of other lepidopteran insects. Phylogenetic reconstruction was conducted using the concatenated 13 protein-coding gene (PCG) sequences of 19 available butterfly species covering all the five butterfly families (Papilionidae, Nymphalidae, Peridae, Lycaenidae and Riodinidae). Both maximum likelihood and Bayesian inference analyses highly supported the monophyly of Lycaenidae+Riodinidae, which was standing as the sister of Nymphalidae. In addition, we propose that the riodinids be categorized into the family Lycaenidae as a subfamilial taxon.

The Full Scope of Family Physicians' Work Is Not Reflected by Current Procedural Terminology Codes.

PubMed

Young, Richard A; Burge, Sandy; Kumar, Kaparaboyna Ashok; Wilson, Jocelyn

2017-01-01

The purpose of this study was to characterize the content of family physician (FP) clinic encounters, and to count the number of visits in which the FPs addressed issues not explicitly reportable by 99211 to 99215 and 99354 Current Procedural Terminology (CPT) codes with current reimbursement methods and based on examples provided in the CPT manual. The data collection instrument was modeled on the National Ambulatory Medical Care Survey. Trained assistants directly observed every other FP-patient encounter and recorded every patient concern, issue addressed by the physician (including care barriers related to health care systems and social determinants), and treatment ordered in clinics affiliated with 10 residencies of the Residency Research Network of Texas. A visit was deemed to include physician work that was not explicitly reportable if the number or nature of issues addressed exceeded the definitions or examples for 99205/99215 or 99214 + 99354 or a preventive service code, included the physician addressing health care system or social determinant issues, or included the care of a family member. In 982 physician-patient encounters, patients raised 517 different reasons for visit (total, 5278; mean, 5.4 per visit; range, 1 to 16) and the FPs addressed 509 different issues (total issues, 3587; mean, 3.7 per visit; range, 1 to 10). FPs managed 425 different medications, 18 supplements, and 11 devices. A mean of 3.9 chronic medications were continued per visit (range, 0 to 21) and 4.6 total medications were managed (range, 0 to 22). In 592 (60.3%) of the visits the FPs did work that was not explicitly reportable with available CPT codes: 582 (59.3%) addressed more numerous issues than explicitly reportable, 64 (6.5%) addressed system barriers, and 13 (1.3%) addressed concerns for other family members. FPs perform cognitive work in a majority of their patient encounters that are not explicitly reportable, either by being higher than the CPT example number of diagnoses per code or the type of problems addressed, which has implications for the care of complex multi-morbid patients and the growth of the primary care workforce. To address these limitations, either the CPT codes and their associated rules should be updated to reflect the realities of family physicians' practices or new billing and coding approaches should be developed. © Copyright 2017 by the American Board of Family Medicine.

The Mudawwana and Koranic Law from a Gender Perspective. The Substantial Changes in the Moroccan Family Code of 2004

ERIC Educational Resources Information Center

Cabre, Yolanda Aixela

2007-01-01

This paper shows how Koranic Law was enshrined in the Moroccan Family Code (the "Mudawwana") in its first draft between the years 1957 and 1958. The changes that were included in 1993 and especially in 2004 partially modify the philosophy of Islamic resources and give more freedom of action to women. At present, the "Mudawwana…

X-linked Charcot-Marie-Tooth (CMT) neuropathies (CMTX1, CMTX2, CMTX3) show different clinical phenotype and molecular genetics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ionasescu, V.V.; Searby, C.C.; Ionasescu, R.

1994-09-01

The purpose of this study was to compare the X-linked dominant type CMTX1 (20 families) with X-linked recessive types CMTX2 and CMTX3 (2 families). The clinical phenotype was consistent with CMT peripheral neuropathy in all cases including distal weakness, atrophy and sensory loss, pes cavus and areflexia. Additional clinicial involvement of the central nervous system was present in one family with CMTX2 (mental retardation) and one family with CMTX3 (spastic paraparesis). Tight genetic linkage to Xq13.1 was present in 20 families with CMTX1 (Z=34.07 at {theta}=0) for the marker DXS453. Fifteen of the CMTX1 families showed point mutations of themore » connexin 32 coding region (5 nonsense mutations, 8 missense mutations, 2 deletions). Five CMTX1 neuropathy families showed no evidence of point mutations of the CX32 coding sequence. These findings suggest that the CMTX1 neuropathy genotype in these families may be the result of promoter mutations, 3{prime}-untranslated region mutations or exon/intron splice site mutations or a mutation with a different type of connexin but which has close structural similarities to CX32. No mutations of the CX32 coding region were found in the CMTX2 or CMTX3 families. Linkage to Xq13.1 was excluded in both families. Genetic linkage to Xp22.2 was present in the CMTX2 family (Z=3.54 at {theta}=0) for the markers DXS987 and DXS999. Suggestion of linkage to Xq26 (Z=1.81 at {theta}=0) for the marker DXS86 was present in the CMTX3 family.« less

Ethics and the Early Childhood Educator: Using the NAEYC Code. 2005 Code Edition

ERIC Educational Resources Information Center

Freeman, Nancy; Feeney, Stephanie

2005-01-01

With updated language and references to the 2005 revision of the Code of Ethical Conduct, this book, like the NAEYC Code of Ethical Conduct, seeks to inform, not prescribe, answers to tough questions that teachers face as they work with children, families, and colleagues. To help everyone become well acquainted with the Code and use it in one's…

Properties of a certain stochastic dynamical system, channel polarization, and polar codes

NASA Astrophysics Data System (ADS)

Tanaka, Toshiyuki

2010-06-01

A new family of codes, called polar codes, has recently been proposed by Arikan. Polar codes are of theoretical importance because they are provably capacity achieving with low-complexity encoding and decoding. We first discuss basic properties of a certain stochastic dynamical system, on the basis of which properties of channel polarization and polar codes are reviewed, with emphasis on our recent results.

On Frequency Offset Estimation Using the iNET Preamble in Frequency Selective Fading Channels

DTIC Science & Technology

2014-03-01

ASM fields; (bottom) the relationship between the indexes of the received samples r(n), the signal samples s(n), the preamble samples p (n) and the short...frequency offset estimators for SOQPSK-TG equipped with the iNET preamble and operating in ISI channels. Four of the five estimators exam - ined here are...sync marker ( ASM ), and data bits (an LDPC codeword). The availability of a preamble introduces the possibility of data-aided synchro- nization in

Pedagogic Practices in the Family Socializing Context and Children's School Achievement

ERIC Educational Resources Information Center

Neves, Isabel P.; Morais, Ana M.

2005-01-01

This paper describes a qualitative study about pedagogic practices in the family. The pedagogic code underlying family practices is characterized and related to specific social groups. Students' achievement is discussed in relation to family and school pedagogic practices. The analysis of family pedagogic practice was based on a model derived from…

A Brief Report on the Ethical and Legal Guides For Technology Use in Marriage and Family Therapy.

PubMed

Pennington, Michael; Patton, Rikki; Ray, Amber; Katafiasz, Heather

2017-10-01

Marriage and family therapists (MFTs) use ethical codes and state licensure laws/rules as guidelines for best clinical practice. It is important that professional codes reflect the potential exponential use of technology in therapy. However, current standards regarding technology use lack clarity. To explore this gap, a summative content analysis was conducted on state licensure laws/rules and professional ethical codes to find themes and subthemes among the many aspects of therapy in which technology can be utilized. Findings from the content analysis indicated that while there have been efforts by both state and professional organizations to incorporate guidance for technology use in therapy, a clear and comprehensive "roadmap" is still missing. Future scholarship is needed that develops clearer guidelines for therapists. © 2017 American Association for Marriage and Family Therapy.

Methodological considerations for observational coding of eating and feeding behaviors in children and their families.

PubMed

Pesch, Megan H; Lumeng, Julie C

2017-12-15

Behavioral coding of videotaped eating and feeding interactions can provide researchers with rich observational data and unique insights into eating behaviors, food intake, food selection as well as interpersonal and mealtime dynamics of children and their families. Unlike self-report measures of eating and feeding practices, the coding of videotaped eating and feeding behaviors can allow for the quantitative and qualitative examinations of behaviors and practices that participants may not self-report. While this methodology is increasingly more common, behavioral coding protocols and methodology are not widely shared in the literature. This has important implications for validity and reliability of coding schemes across settings. Additional guidance on how to design, implement, code and analyze videotaped eating and feeding behaviors could contribute to advancing the science of behavioral nutrition. The objectives of this narrative review are to review methodology for the design, operationalization, and coding of videotaped behavioral eating and feeding data in children and their families, and to highlight best practices. When capturing eating and feeding behaviors through analysis of videotapes, it is important for the study and coding to be hypothesis driven. Study design considerations include how to best capture the target behaviors through selection of a controlled experimental laboratory environment versus home mealtime, duration of video recording, number of observations to achieve reliability across eating episodes, as well as technical issues in video recording and sound quality. Study design must also take into account plans for coding the target behaviors, which may include behavior frequency, duration, categorization or qualitative descriptors. Coding scheme creation and refinement occur through an iterative process. Reliability between coders can be challenging to achieve but is paramount to the scientific rigor of the methodology. Analysis approach is dependent on the how data were coded and collapsed. Behavioral coding of videotaped eating and feeding behaviors can capture rich data "in-vivo" that is otherwise unobtainable from self-report measures. While data collection and coding are time-intensive the data yielded can be extremely valuable. Additional sharing of methodology and coding schemes around eating and feeding behaviors could advance the science and field.

Potential application of item-response theory to interpretation of medical codes in electronic patient records

PubMed Central

2011-01-01

Background Electronic patient records are generally coded using extensive sets of codes but the significance of the utilisation of individual codes may be unclear. Item response theory (IRT) models are used to characterise the psychometric properties of items included in tests and questionnaires. This study asked whether the properties of medical codes in electronic patient records may be characterised through the application of item response theory models. Methods Data were provided by a cohort of 47,845 participants from 414 family practices in the UK General Practice Research Database (GPRD) with a first stroke between 1997 and 2006. Each eligible stroke code, out of a set of 202 OXMIS and Read codes, was coded as either recorded or not recorded for each participant. A two parameter IRT model was fitted using marginal maximum likelihood estimation. Estimated parameters from the model were considered to characterise each code with respect to the latent trait of stroke diagnosis. The location parameter is referred to as a calibration parameter, while the slope parameter is referred to as a discrimination parameter. Results There were 79,874 stroke code occurrences available for analysis. Utilisation of codes varied between family practices with intraclass correlation coefficients of up to 0.25 for the most frequently used codes. IRT analyses were restricted to 110 Read codes. Calibration and discrimination parameters were estimated for 77 (70%) codes that were endorsed for 1,942 stroke patients. Parameters were not estimated for the remaining more frequently used codes. Discrimination parameter values ranged from 0.67 to 2.78, while calibration parameters values ranged from 4.47 to 11.58. The two parameter model gave a better fit to the data than either the one- or three-parameter models. However, high chi-square values for about a fifth of the stroke codes were suggestive of poor item fit. Conclusion The application of item response theory models to coded electronic patient records might potentially contribute to identifying medical codes that offer poor discrimination or low calibration. This might indicate the need for improved coding sets or a requirement for improved clinical coding practice. However, in this study estimates were only obtained for a small proportion of participants and there was some evidence of poor model fit. There was also evidence of variation in the utilisation of codes between family practices raising the possibility that, in practice, properties of codes may vary for different coders. PMID:22176509

Bandwidth-Efficient Communication through 225 MHz Ka-band Relay Satellite Channel

NASA Technical Reports Server (NTRS)

Downey, Joseph; Downey, James; Reinhart, Richard C.; Evans, Michael Alan; Mortensen, Dale John

2016-01-01

The communications and navigation space infrastructure of the National Aeronautics and Space Administration (NASA) consists of a constellation of relay satellites (called Tracking and Data Relay Satellites (TDRS)) and a global set of ground stations to receive and deliver data to researchers around the world from mission spacecraft throughout the solar system. Planning is underway to enhance and transform the infrastructure over the coming decade. Key to the upgrade will be the simultaneous and efficient use of relay transponders to minimize cost and operations while supporting science and exploration spacecraft. Efficient use of transponders necessitates bandwidth efficient communications to best use and maximize data throughput within the allocated spectrum. Experiments conducted with NASA's Space Communication and Navigation (SCaN) Testbed on the International Space Station provides a unique opportunity to evaluate advanced communication techniques, such as bandwidth-efficient modulations, in an operational flight system. Demonstrations of these new techniques in realistic flight conditions provides critical experience and reduces the risk of using these techniques in future missions. Efficient use of spectrum is enabled by using high-order modulations coupled with efficient forward error correction codes. This paper presents a high-rate, bandwidth-efficient waveform operating over the 225 MHz Ka-band service of the TDRS System (TDRSS). The testing explores the application of Gaussian Minimum Shift Keying (GMSK), 248-phase shift keying (PSK) and 1632- amplitude PSK (APSK) providing over three bits-per-second-per-Hertz (3 bsHz) modulation combined with various LDPC encoding rates to maximize throughput. With a symbol rate of 200 Mbaud, coded data rates of 1000 Mbps were tested in the laboratory and up to 800 Mbps over the TDRS 225 MHz channel. This paper will present on the high-rate waveform design, channel characteristics, performance results, compensation techniques for filtering and equalization, and architecture considerations going forward for efficient use of NASA's infrastructure.

Bandwidth-Efficient Communication through 225 MHz Ka-band Relay Satellite Channel

NASA Technical Reports Server (NTRS)

Downey, Joseph A.; Downey, James M.; Reinhart, Richard C.; Evans, Michael A.; Mortensen, Dale J.

2016-01-01

The communications and navigation space infrastructure of the National Aeronautics and Space Administration (NASA) consists of a constellation of relay satellites (called Tracking and Data Relay Satellites (TDRS)) and a global set of ground stations to receive and deliver data to researchers around the world from mission spacecraft throughout the solar system. Planning is underway to enhance and transform the infrastructure over the coming decade. Key to the upgrade will be the simultaneous and efficient use of relay transponders to minimize cost and operations while supporting science and exploration spacecraft. Efficient use of transponders necessitates bandwidth efficient communications to best use and maximize data throughput within the allocated spectrum. Experiments conducted with NASA's Space Communication and Navigation (SCaN) Testbed on the International Space Station provides a unique opportunity to evaluate advanced communication techniques, such as bandwidth-efficient modulations, in an operational flight system. Demonstrations of these new techniques in realistic flight conditions provides critical experience and reduces the risk of using these techniques in future missions. Efficient use of spectrum is enabled by using high-order modulations coupled with efficient forward error correction codes. This paper presents a high-rate, bandwidth-efficient waveform operating over the 225 MHz Ka-band service of the TDRS System (TDRSS). The testing explores the application of Gaussian Minimum Shift Keying (GMSK), 2/4/8-phase shift keying (PSK) and 16/32- amplitude PSK (APSK) providing over three bits-per-second-per-Hertz (3 b/s/Hz) modulation combined with various LDPC encoding rates to maximize through- put. With a symbol rate of 200 M-band, coded data rates of 1000 Mbps were tested in the laboratory and up to 800 Mbps over the TDRS 225 MHz channel. This paper will present on the high-rate waveform design, channel characteristics, performance results, compensation techniques for filtering and equalization, and architecture considerations going forward for efficient use of NASA's infrastructure.

Assessing patient-centered communication in a family practice setting: how do we measure it, and whose opinion matters?

PubMed

Clayton, Margaret F; Latimer, Seth; Dunn, Todd W; Haas, Leonard

2011-09-01

This study evaluated variables thought to influence patient's perceptions of patient-centeredness. We also compared results from two coding schemes that purport to evaluate patient-centeredness, the Measure of Patient-Centered Communication (MPCC) and the 4 Habits Coding Scheme (4HCS). 174 videotaped family practice office visits, and patient self-report measures were analyzed. Patient factors contributing to positive perceptions of patient-centeredness were successful negotiation of decision-making roles and lower post-visit uncertainty. MPCC coding found visits were on average 59% patient-centered (range 12-85%). 4HCS coding showed an average of 83 points (maximum possible 115). However, patients felt their visits were highly patient-centered (mean 3.7, range 1.9-4; maximum possible 4). There was a weak correlation between coding schemes, but no association between coding results and patient variables (number of pre-visit concerns, attainment of desired decision-making role, post-visit uncertainty, patients' perception of patient-centeredness). Coder inter-rater reliability was lower than expected; convergent and divergent validity were not supported. The 4HCS and MPCC operationalize patient-centeredness differently, illustrating a lack of conceptual clarity. The patient's perspective is important. Family practice providers can facilitate a more positive patient perception of patient-centeredness by addressing patient concerns to help reduce patient uncertainty, and by negotiating decision-making roles. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

24 CFR 200.926 - Minimum property standards for one and two family dwellings.

Code of Federal Regulations, 2012 CFR

2012-04-01

... property is to be located. (c) Standard for evaluating local or state building codes. The Secretary shall compare a local building code submitted under paragraph (d) of this section or a State code to the list of... each area and subarea on the list. (2) A State or local building code will be partially accepted if it...

24 CFR 200.926 - Minimum property standards for one and two family dwellings.

Code of Federal Regulations, 2014 CFR

2014-04-01

... property is to be located. (c) Standard for evaluating local or state building codes. The Secretary shall compare a local building code submitted under paragraph (d) of this section or a State code to the list of... each area and subarea on the list. (2) A State or local building code will be partially accepted if it...

24 CFR 200.926 - Minimum property standards for one and two family dwellings.

Code of Federal Regulations, 2013 CFR

2013-04-01

... property is to be located. (c) Standard for evaluating local or state building codes. The Secretary shall compare a local building code submitted under paragraph (d) of this section or a State code to the list of... each area and subarea on the list. (2) A State or local building code will be partially accepted if it...

Combined Edition of Family Planning Library Manual and Family Planning Classification.

ERIC Educational Resources Information Center

Planned Parenthood--World Population, New York, NY. Katherine Dexter McCormick Library.

This edition combines two previous publications of the Katharine Dexter McCormick Library into one volume: the Family Planning Library Manual, a guide for starting a family planning and population library or information center, and the Family Planning Classification, a coding system for organizing book and non-book materials so that they can be…

The Limits of Coding with Joint Constraints on Detected and Undetected Error Rates

NASA Technical Reports Server (NTRS)

Dolinar, Sam; Andrews, Kenneth; Pollara, Fabrizio; Divsalar, Dariush

2008-01-01

We develop a remarkably tight upper bound on the performance of a parameterized family of bounded angle maximum-likelihood (BA-ML) incomplete decoders. The new bound for this class of incomplete decoders is calculated from the code's weight enumerator, and is an extension of Poltyrev-type bounds developed for complete ML decoders. This bound can also be applied to bound the average performance of random code ensembles in terms of an ensemble average weight enumerator. We also formulate conditions defining a parameterized family of optimal incomplete decoders, defined to minimize both the total codeword error probability and the undetected error probability for any fixed capability of the decoder to detect errors. We illustrate the gap between optimal and BA-ML incomplete decoding via simulation of a small code.

Clinical application of antenatal genetic diagnosis of osteogenesis imperfecta type IV.

PubMed

Yuan, Jing; Li, Song; Xu, YeYe; Cong, Lin

2015-04-02

Clinical analysis and genetic testing of a family with osteogenesis imperfecta type IV were conducted, aiming to discuss antenatal genetic diagnosis of osteogenesis imperfecta type IV. Preliminary genotyping was performed based on clinical characteristics of the family members and then high-throughput sequencing was applied to rapidly and accurately detect the changes in candidate genes. Genetic testing of the III5 fetus and other family members revealed missense mutation in c.2746G>A, pGly916Arg in COL1A2 gene coding region and missense and synonymous mutation in COL1A1 gene coding region. Application of antenatal genetic diagnosis provides fast and accurate genetic counseling and eugenics suggestions for patients with osteogenesis imperfecta type IV and their families.

Codes over infinite family of rings : Equivalence and invariant ring

NASA Astrophysics Data System (ADS)

Irwansyah, Muchtadi-Alamsyah, Intan; Muchlis, Ahmad; Barra, Aleams; Suprijanto, Djoko

2016-02-01

In this paper, we study codes over the ring Bk=𝔽pr[v1,…,vk]/(vi2=vi,∀i =1 ,…,k ) . For instance, we focus on two topics, i.e. characterization of the equivalent condition between two codes over Bk using a Gray map into codes over finite field 𝔽pr, and finding generators for invariant ring of Hamming weight enumerator for Euclidean self-dual codes over Bk.

Closed Genome Sequence of Chryseobacterium piperi Strain CTMT/ATCC BAA-1782, a Gram-Negative Bacterium with Clostridial Neurotoxin-Like Coding Sequences

PubMed Central

Wentz, Travis G.; Muruvanda, Tim; Thirunavukkarasu, Nagarajan; Hoffmann, Maria; Allard, Marc W.; Hodge, David R.; Pillai, Segaran P.; Hammack, Thomas S.; Brown, Eric W.

2017-01-01

ABSTRACT Clostridial neurotoxins, including botulinum and tetanus neurotoxins, are among the deadliest known bacterial toxins. Until recently, the horizontal mobility of this toxin gene family appeared to be limited to the genus Clostridium. We report here the closed genome sequence of Chryseobacterium piperi, a Gram-negative bacterium containing coding sequences with homology to clostridial neurotoxin family proteins. PMID:29192076

Thin family: a new barcode concept

NASA Astrophysics Data System (ADS)

Allais, David C.

1991-02-01

This paper describes a new space-efficient family of thin bar code symbologies which are appropriate for representing small amounts of information. The proposed structure is 30 to 50 percent more compact than the narrowest existing bar code when 12 or fewer bits of information are to be encoded in each symbol. Potential applications for these symbologies include menus catalogs automated test and survey scoring and biological research such as the tracking of honey bees.

Compliance with the International Code of Marketing of breast-milk substitutes: an observational study of pediatricians' waiting rooms.

PubMed

Dodgson, Joan E; Watkins, Amanda L; Bond, Angela B; Kintaro-Tagaloa, Cheryl; Arellano, Alondra; Allred, Patrick A

2014-04-01

Abstract The importance of breastmilk as a primary preventative intervention is widely known and understood by most healthcare providers. The actions or non-actions that heathcare providers take toward promoting and supporting breastfeeding families make a difference in the success and duration of breastfeeding. Recognizing this relationship, the World Health Organization developed the International Code of Marketing of Breast-milk Substitutes (the Code), which defines best practices in breastfeeding promotion, including physicians' offices. The pediatric practices' waiting rooms are often a family's first experience with pediatric care. The specific aims of this study were to describe (1) Code compliance, (2) the demographic factors affecting the Code compliance, and (3) the amount and type of breastfeeding-supportive materials available in the pediatricians' waiting rooms. An observational cross-sectional design was used to collect data from 163 (82%) of the pediatric practices in Maricopa County, Arizona. None of the 100 waiting rooms that had any materials displayed (61%) was found to be completely Code compliant, with 81 of the offices having formula-promotional materials readily available. Waiting rooms in higher income areas offered more non-Code-compliant materials and gifts. Breastfeeding support information and materials were lacking in all but 18 (18%) offices. A positive relationship (t97=-2.31, p=0.02) occurred between the presence of breastfeeding educational materials and higher income areas. We were able to uncover some practice-related patterns that impact families and potentially undermine breastfeeding success. To move current practices toward breastfeeding-friendly physicians' offices, change is needed.

The Validation of Macro and Micro Observations of Parent-Child Dynamics Using the Relationship Affect Coding System in Early Childhood.

PubMed

Dishion, Thomas J; Mun, Chung Jung; Tein, Jenn-Yun; Kim, Hanjoe; Shaw, Daniel S; Gardner, Frances; Wilson, Melvin N; Peterson, Jenene

2017-04-01

This study examined the validity of micro social observations and macro ratings of parent-child interaction in early to middle childhood. Seven hundred and thirty-one families representing multiple ethnic groups were recruited and screened as at risk in the context of Women, Infant, and Children (WIC) Nutritional Supplement service settings. Families were randomly assigned to the Family Checkup (FCU) intervention or the control condition at age 2 and videotaped in structured interactions in the home at ages 2, 3, 4, and 5. Parent-child interaction videotapes were micro-coded using the Relationship Affect Coding System (RACS) that captures the duration of two mutual dyadic states: positive engagement and coercion. Macro ratings of parenting skills were collected after coding the videotapes to assess parent use of positive behavior support and limit setting skills (or lack thereof). Confirmatory factor analyses revealed that the measurement model of macro ratings of limit setting and positive behavior support was not supported by the data, and thus, were excluded from further analyses. However, there was moderate stability in the families' micro social dynamics across early childhood and it showed significant improvements as a function of random assignment to the FCU. Moreover, parent-child dynamics were predictive of chronic behavior problems as rated by parents in middle childhood, but not emotional problems. We conclude with a discussion of the validity of the RACS and on methodological advantages of micro social coding over the statistical limitations of macro rating observations. Future directions are discussed for observation research in prevention science.

26 CFR 1.262-1 - Personal, living, and family expenses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 3 2011-04-01 2011-04-01 false Personal, living, and family expenses. 1.262-1... TAX (CONTINUED) INCOME TAXES (CONTINUED) Items Not Deductible § 1.262-1 Personal, living, and family... expressly provided in chapter 1 of the Code, for personal, living, and family expenses. (b) Examples of...

When Families Present with Concerns about an Adolescent's Experience of Same-Sex Attraction.

ERIC Educational Resources Information Center

Yarhouse, Mark A.

1998-01-01

Examines the American Association for Marital and Family Therapy's Code of Ethics to explore ways in which marriage and family therapists can provide services within the framework of existing ethical principles and standards for accountability and professionalism to families with an adolescent child experiencing same-sex attraction. (Author/MKA)

Three Measures of Family Problem Solving Behavior: A Procedural Manual.

ERIC Educational Resources Information Center

Nickerson, Mark; And Others

The procedural details of three measures of family problem-solving behavior are presented. These measures are used to code videotapes that are recorded when family members discuss and try to solve a family problem that they consider important. The measures were developed to accompany methods for training parents and their preadolescent and…

Perceptions of Family Participation in Intensive Care Unit Rounds and Telemedicine: A Qualitative Assessment.

PubMed

Stelson, Elisabeth A; Carr, Brendan G; Golden, Kate E; Martin, Niels; Richmond, Therese S; Delgado, M Kit; Holena, Daniel N

2016-09-01

Family-centered rounds involve purposeful interactions between patients' families and care providers to refocus the delivery of care on patients' needs. To examine perspectives of patients' family members and health care providers on family participation in rounds in the surgical intensive care unit (ICU) and the potential use of telemedicine to facilitate this process. Patients' family members and surgical ICU care providers were recruited for semistructured interviews exploring stakeholders' perspectives on family participation in ICU rounds and the potential role of telemedicine. Thirty-two interviews were conducted, audio recorded, and transcribed verbatim. Common coding methods were facilitated by using NVivo 10. A mean coding agreement of 97.3% was calculated for 22% of transcripts. Both patients' family members and health care providers described inconsistent practices surrounding family participation in ICU rounds as well as barriers to and facilitators of family participation. Family members identified 3 primary logistical challenges to participation in ICU rounds: distance to hospitals, work/family obligations, and the rounding schedule. Both family members and providers reported receptivity to virtual participation as a potential solution to these challenges. Understanding the barriers to and facilitators of family participation in ICU rounds is key to encouraging adoption of family-centered rounds. For families that live far away or have competing demands, telemedical options may facilitate participation. ©2016 American Association of Critical-Care Nurses.

Design and System Implications of a Family of Wideband HF Data Waveforms

DTIC Science & Technology

2010-09-01

code rates (i.e. 8/9, 9/10) will be used to attain the highest data rates for surface wave links. Very high puncturing of convolutional codes can...Communication Links”, Edition 1, North Atlantic Treaty Organization, 2009. [14] Yasuda, Y., Kashiki, K., Hirata, Y. “High- Rate Punctured Convolutional Codes ...length 7 convolutional code that has been used for over two decades in 110A. In addition, repetition coding and puncturing was

Influence of Familial Spirituality: Implications for School Counseling Professionals

ERIC Educational Resources Information Center

Davis, Keith M.; Lambie, Glenn W.; Ieva, Kara P.

2011-01-01

This article (a) addresses the importance of familial spirituality on students' holistic development; (b) explores professional ethical codes, standards, and counseling competencies relating to students' familial spirituality; (c) introduces educational activities to assist school counselors in increasing their understanding and appreciation of…

Successful Therapist-Parent Coaching: How In Vivo Feedback Relates to Parent Engagement in Parent-Child Interaction Therapy.

PubMed

Barnett, Miya L; Niec, Larissa N; Peer, Samuel O; Jent, Jason F; Weinstein, Allison; Gisbert, Patricia; Simpson, Gregory

2017-01-01

Although behavioral parent training is considered efficacious treatment for childhood conduct problems, not all families benefit equally from treatment. Some parents take longer to change their behaviors and others ultimately drop out. Understanding how therapist behaviors impact parental engagement is necessary to improve treatment utilization. This study investigated how different techniques of therapist in vivo feedback (i.e., coaching) influenced parent attrition and skill acquisition in parent-child interaction therapy (PCIT). Participants included 51 parent-child dyads who participated in PCIT. Children (age: M = 5.03, SD = 1.65) were predominately minorities (63% White Hispanic, 16% African American or Black). Eight families discontinued treatment prematurely. Therapist coaching techniques during the first session of treatment were coded using the Therapist-Parent Interaction Coding System, and parent behaviors were coded with the Dyadic Parent-Child Interaction Coding System, Third Edition. Parents who received more responsive coaching acquired child-centered parenting skills more quickly. Therapists used fewer responsive techniques and more drills with families who dropped out of treatment. A composite of therapist behaviors accurately predicted treatment completion for 86% of families. Although group membership was correctly classified for the treatment completers, only 1 dropout was accurately predicted. Findings suggest that therapist in vivo feedback techniques may impact parents' success in PCIT and that responsive coaching may be particularly relevant.

MeshVoro: A Three-Dimensional Voronoi Mesh Building Tool for the TOUGH Family of Codes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Freeman, C. M.; Boyle, K. L.; Reagan, M.

2013-09-30

Few tools exist for creating and visualizing complex three-dimensional simulation meshes, and these have limitations that restrict their application to particular geometries and circumstances. Mesh generation needs to trend toward ever more general applications. To that end, we have developed MeshVoro, a tool that is based on the Voro (Rycroft 2009) library and is capable of generating complex threedimensional Voronoi tessellation-based (unstructured) meshes for the solution of problems of flow and transport in subsurface geologic media that are addressed by the TOUGH (Pruess et al. 1999) family of codes. MeshVoro, which includes built-in data visualization routines, is a particularly usefulmore » tool because it extends the applicability of the TOUGH family of codes by enabling the scientifically robust and relatively easy discretization of systems with challenging 3D geometries. We describe several applications of MeshVoro. We illustrate the ability of the tool to straightforwardly transform a complex geological grid into a simulation mesh that conforms to the specifications of the TOUGH family of codes. We demonstrate how MeshVoro can describe complex system geometries with a relatively small number of grid blocks, and we construct meshes for geometries that would have been practically intractable with a standard Cartesian grid approach. We also discuss the limitations and appropriate applications of this new technology.« less

Factors Affecting Christian Parents' School Choice Decision Processes: A Grounded Theory Study

ERIC Educational Resources Information Center

Prichard, Tami G.; Swezey, James A.

2016-01-01

This study identifies factors affecting the decision processes for school choice by Christian parents. Grounded theory design incorporated interview transcripts, field notes, and a reflective journal to analyze themes. Comparative analysis, including open, axial, and selective coding, was used to reduce the coded statements to five code families:…

Some partial-unit-memory convolutional codes

NASA Technical Reports Server (NTRS)

Abdel-Ghaffar, K.; Mceliece, R. J.; Solomon, G.

1991-01-01

The results of a study on a class of error correcting codes called partial unit memory (PUM) codes are presented. This class of codes, though not entirely new, has until now remained relatively unexplored. The possibility of using the well developed theory of block codes to construct a large family of promising PUM codes is shown. The performance of several specific PUM codes are compared with that of the Voyager standard (2, 1, 6) convolutional code. It was found that these codes can outperform the Voyager code with little or no increase in decoder complexity. This suggests that there may very well be PUM codes that can be used for deep space telemetry that offer both increased performance and decreased implementational complexity over current coding systems.

5 CFR 630.201 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... with the employee is the equivalent of a family relationship. Health care provider has the meaning... Code, applies. Family member means the following relatives of the employee: (1) Spouse, and parents...

Identification of three novel NHS mutations in families with Nance-Horan syndrome.

PubMed

Huang, Kristen M; Wu, Junhua; Brooks, Simon P; Hardcastle, Alison J; Lewis, Richard Alan; Stambolian, Dwight

2007-03-27

Nance-Horan Syndrome (NHS) is an infrequent and often overlooked X-linked disorder characterized by dense congenital cataracts, microphthalmia, and dental abnormalities. The syndrome is caused by mutations in the NHS gene, whose function is not known. The purpose of this study was to identify the frequency and distribution of NHS gene mutations and compare genotype with Nance-Horan phenotype in five North American NHS families. Genomic DNA was isolated from white blood cells from NHS patients and family members. The NHS gene coding region and its splice site donor and acceptor regions were amplified from genomic DNA by PCR, and the amplicons were sequenced directly. We identified three unique NHS coding region mutations in these NHS families. This report extends the number of unique identified NHS mutations to 14.

THE CODE OF THE STREET AND INMATE VIOLENCE: INVESTIGATING THE SALIENCE OF IMPORTED BELIEF SYSTEMS*

PubMed Central

MEARS, DANIEL P.; STEWART, ERIC A.; SIENNICK, SONJA E.; SIMONS, RONALD L.

2013-01-01

Scholars have long argued that inmate behaviors stem in part from cultural belief systems that they “import” with them into incarcerative settings. Even so, few empirical assessments have tested this argument directly. Drawing on theoretical accounts of one such set of beliefs—the code of the street—and on importation theory, we hypothesize that individuals who adhere more strongly to the street code will be more likely, once incarcerated, to engage in violent behavior and that this effect will be amplified by such incarceration experiences as disciplinary sanctions and gang involvement, as well as the lack of educational programming, religious programming, and family support. We test these hypotheses using unique data that include measures of the street code belief system and incarceration experiences. The results support the argument that the code of the street belief system affects inmate violence and that the effect is more pronounced among inmates who lack family support, experience disciplinary sanctions, and are gang involved. Implications of these findings are discussed. PMID:24068837

Direct observation of mother-child communication in pediatric cancer: assessment of verbal and non-verbal behavior and emotion.

PubMed

Dunn, Madeleine J; Rodriguez, Erin M; Miller, Kimberly S; Gerhardt, Cynthia A; Vannatta, Kathryn; Saylor, Megan; Scheule, C Melanie; Compas, Bruce E

2011-06-01

To examine the acceptability and feasibility of coding observed verbal and nonverbal behavioral and emotional components of mother-child communication among families of children with cancer. Mother-child dyads (N=33, children ages 5-17 years) were asked to engage in a videotaped 15-min conversation about the child's cancer. Coding was done using the Iowa Family Interaction Rating Scale (IFIRS). Acceptability and feasibility of direct observation in this population were partially supported: 58% consented and 81% of those (47% of all eligible dyads) completed the task; trained raters achieved 78% agreement in ratings across codes. The construct validity of the IFIRS was demonstrated by expected associations within and between positive and negative behavioral/emotional code ratings and between mothers' and children's corresponding code ratings. Direct observation of mother-child communication about childhood cancer has the potential to be an acceptable and feasible method of assessing verbal and nonverbal behavior and emotion in this population.

How does family intervention improve the outcome of people with schizophrenia?

PubMed

Girón, Manuel; Nova-Fernández, Francisco; Mañá-Alvarenga, Sonia; Nolasco, Andreu; Molina-Habas, Antonia; Fernández-Yañez, Antonio; Tabarés-Seisdedos, Rafael; Gómez-Beneyto, Manuel

2015-03-01

There is strong evidence of the efficacy of family psychosocial interventions for schizophrenia, but evidence of the role played by the attitudes of relatives in the therapeutic process is lacking. To study the effect of a family intervention on family attitudes and to analyse their mediating role in the therapeutic process 50 patients with schizophrenia and their key relatives undergoing a trial on the efficacy of a family psychosocial intervention were studied by means of the Affective Style Coding System, the Scale of Empathy, and the Relational Control Coding System. Specific statistical methods were used to determine the nature of the relationship of the relatives' attitudes to the outcome of family intervention. Family psychosocial intervention was associated with a reduction in relatives' guilt induction and dominance and an improvement in empathy. Empathy and lack of dominance were identified as independent mediators of the effect of family psychosocial intervention. The change in empathy and dominance during the first 9 months of the intervention predicted the outcome in the following 15 months. Relatives' empathy and lack of dominance are mediators of the beneficial effect of family psychosocial intervention on patient's outcome.

Family diabetes matters: a view from the other side.

PubMed

Samuel-Hodge, Carmen D; Cene, Crystal W; Corsino, Leonor; Thomas, Chelsea; Svetkey, Laura P

2013-03-01

Typically, chronic disease self-management happens in a family context, and for African American adults living with diabetes, family seems to matter in self-management processes. Many qualitative studies describe family diabetes interactions from the perspective of adults living with diabetes, but we have not heard from family members. To explore patient and family perspectives on family interactions around diabetes. Qualitative study using focus group methodology. PARTICIPANTS & APPROACH: We conducted eight audiotaped focus groups among African Americans (four with patients with diabetes and four with family members not diagnosed with diabetes), with a focus on topics of family communication, conflict, and support. The digital files were transcribed verbatim, coded, and analyzed using qualitative data analysis software. Directed content analysis and grounded theory approaches guided the interpretation of code summaries. Focus groups included 67 participants (81 % female, mean age 64 years). Family members primarily included spouses, siblings, and adult children/grandchildren. For patients with diabetes, central issues included shifting family roles to accommodate diabetes and conflicts stemming from family advice-giving. Family members described discomfort with the perceived need to police or "stand over" the diabetic family member, not wanting to "throw diabetes in their [relative's] face," perceiving their communications as unhelpful, and confusion about their role in diabetes care. These concepts generated an emergent theme of "family diabetes silence." Diabetes silence, role adjustments, and conflict appear to be important aspects to address in family-centered diabetes self-management interventions. Contextual data gathered through formative research can inform such family-centered intervention development.

Counseling Suicidal Adolescents within Family Systems: Ethical Issues

ERIC Educational Resources Information Center

Berg, Rachelle; Hendricks, Bret; Bradley, Loretta

2009-01-01

Major ethical considerations must be taken into account when providing counseling services to suicidal adolescents and their families. This article explores these ethical issues and the American Counseling Association and International Association of Marriage and Family Counselors ethical codes relevant to these issues. Related liability and…

Communicating with families about post-mortems: practice guidance.

PubMed

Henderson, Nicola

2006-02-01

In January 2001 the Chief Medical Officer announced the Public Inquiry (Redfern Report) into post-mortem practice at Alder Hey Hospital in Liverpool. It was expected that this inquiry report would influence post-mortem practice in general and communication with parents in particular and in May 2003 a code of practice for clinical staff was produced by the Department of Health (DH) (2003a). This article discusses the code of practice Families and Post Mortems and explores the relevance of these recommendations to neonatal and children's nurses.

Structuring and coding in health care records: a qualitative analysis using diabetes as a case study.

PubMed

Robertson, Ann R R; Fernando, Bernard; Morrison, Zoe; Kalra, Dipak; Sheikh, Aziz

2015-03-27

Globally, diabetes mellitus presents a substantial and increasing burden to individuals, health care systems and society. Structuring and coding of information in the electronic health record underpin attempts to improve sharing and searching for information. Digital records for those with long-term conditions are expected to bring direct and secondary uses benefits, and potentially to support patient self-management. We sought to investigate if how and why records for adults with diabetes were structured and coded and to explore a range of UK stakeholders' perceptions of current practice in the National Health Service. We carried out a qualitative, theoretically informed case study of documenting health care information for diabetes in family practice and hospital settings in England, using semi-structured interviews, observations, systems demonstrations and documentary data. We conducted 22 interviews and four on-site observations. With respect to secondary uses - research, audit, public health and service planning - interviewees clearly articulated the benefits of highly structured and coded diabetes data and it was believed that benefits would expand through linkage to other datasets. Direct, more marginal, clinical benefits in terms of managing and monitoring diabetes and perhaps encouraging patient self-management were also reported. We observed marked differences in levels of record structuring and/or coding between family practices, where it was high, and the hospital. We found little evidence that structured and coded data were being exploited to improve information sharing between care settings. Using high levels of data structuring and coding in records for diabetes patients has the potential to be exploited more fully, and lessons might be learned from successful developments elsewhere in the UK. A first step would be for hospitals to attain levels of health information technology infrastructure and systems use commensurate with family practices.

Gender Differences in Bladder Cancer Treatment Decision Making.

PubMed

Pozzar, Rachel A; Berry, Donna L

2017-03-01

To explore gender differences in bladder cancer treatment decision making.
. Secondary qualitative analysis of interview transcripts.
. One multidisciplinary genitourinary oncology clinic (Dana-Farber Cancer Institute) and two urology clinics (Brigham and Women's Hospital and Beth Israel Deaconess Medical Center) in Boston, MA.
. As part of the original study, 45 men and 15 women with bladder cancer participated in individual interviews. Participants were primarily Caucasian, and most had at least some college education.
. Word frequency reports were used to identify thematic differences between the men's and women's statements. Line-by-line coding of constructs prevalent among women was then performed on all participants in NVivo 9. Coding results were compared between genders using matrix coding queries.
. The role of family in the decision-making process was found to be a dominant theme for women but not for men. Women primarily described family members as facilitators of bladder cancer treatment-related decisions, but men were more likely to describe family in a nonsupportive role.
. The results suggest that influences on the decision-making process are different for men and women with bladder cancer. Family may play a particularly important role for women faced with bladder cancer treatment-related decisions.
. Clinical nurses who care for individuals with bladder cancer should routinely assess patients' support systems and desired level of family participation in decision making. For some people with bladder cancer, family may serve as a stressor. Nurses should support the decision-making processes of all patients and be familiar with resources that can provide support to patients who do not receive it from family.

Support de la famille dans l'education: Quelques aspects de la realite grecque (Support of the Family for Education: Aspects of the Situation in Greece).

ERIC Educational Resources Information Center

Varnava-Skoura, Gella

1992-01-01

Describes extended family structure in Greece and offers a profile of the family backgrounds of university students. Finds that the cultural capital and sociolinguistic codes of families are not determining factors for university entry in Greece. University students come from clerical and mixed families, who are willing to make necessary financial…

5 CFR 630.1201 - Purpose, applicability, and administration.

Code of Federal Regulations, 2010 CFR

2010-01-01

... REGULATIONS ABSENCE AND LEAVE Family and Medical Leave § 630.1201 Purpose, applicability, and administration... 6387 of title 5, United States Code, provide a standard approach to providing family and medical leave... unpaid leave during any 12-month period for certain family and medical needs, as specified in § 630.1203...

Second Language Socialization and Learner Agency: Adoptive Family Talk

ERIC Educational Resources Information Center

Fogle, Lyn Wright

2012-01-01

This book examines how Russian-speaking adoptees in three US families actively shape opportunities for language learning and identity construction in everyday interactions. By focusing on a different practice in each family (i.e. narrative talk about the day, metalinguistic discourse or languaging, and code-switching), the analyses uncover…

10 CFR 434.512 - Internal loads.

Code of Federal Regulations, 2010 CFR

2010-01-01

... OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE... Proposed Design or for calculation of Design Energy Cost. 512.2Internal loads for multi-family high-rise residential buildings are prescribed in Tables 512.2.a and b, Multi-Family High Rise Residential Building...

Children's Family Drawings: A Study of Attachment, Personality, and Adjustment

ERIC Educational Resources Information Center

Goldner, Limor; Scharf, Miri

2011-01-01

This study examined the relationship between children's attachment security, as manifested in their family drawings, and their personality and adjustment. Family drawings were collected from 222 Israeli children, as well as data regarding their personality and adjustment. Each drawing was coded and classified into 1 of 4 attachment categories…

Identification of three novel NHS mutations in families with Nance-Horan syndrome

PubMed Central

Wu, Junhua; Brooks, Simon P.; Hardcastle, Alison J.; Lewis, Richard Alan; Stambolian, Dwight

2007-01-01

Purpose Nance-Horan Syndrome (NHS) is an infrequent and often overlooked X-linked disorder characterized by dense congenital cataracts, microphthalmia, and dental abnormalities. The syndrome is caused by mutations in the NHS gene, whose function is not known. The purpose of this study was to identify the frequency and distribution of NHS gene mutations and compare genotype with Nance-Horan phenotype in five North American NHS families. Methods Genomic DNA was isolated from white blood cells from NHS patients and family members. The NHS gene coding region and its splice site donor and acceptor regions were amplified from genomic DNA by PCR, and the amplicons were sequenced directly. Results We identified three unique NHS coding region mutations in these NHS families. Conclusions This report extends the number of unique identified NHS mutations to 14. PMID:17417607

Rare Coding Variants in ANGPTL6 Are Associated with Familial Forms of Intracranial Aneurysm.

PubMed

Bourcier, Romain; Le Scouarnec, Solena; Bonnaud, Stéphanie; Karakachoff, Matilde; Bourcereau, Emmanuelle; Heurtebise-Chrétien, Sandrine; Menguy, Céline; Dina, Christian; Simonet, Floriane; Moles, Alexis; Lenoble, Cédric; Lindenbaum, Pierre; Chatel, Stéphanie; Isidor, Bertrand; Génin, Emmanuelle; Deleuze, Jean-François; Schott, Jean-Jacques; Le Marec, Hervé; Loirand, Gervaise; Desal, Hubert; Redon, Richard

2018-01-04

Intracranial aneurysms (IAs) are acquired cerebrovascular abnormalities characterized by localized dilation and wall thinning in intracranial arteries, possibly leading to subarachnoid hemorrhage and severe outcome in case of rupture. Here, we identified one rare nonsense variant (c.1378A>T) in the last exon of ANGPTL6 (Angiopoietin-Like 6)-which encodes a circulating pro-angiogenic factor mainly secreted from the liver-shared by the four tested affected members of a large pedigree with multiple IA-affected case subjects. We showed a 50% reduction of ANGPTL6 serum concentration in individuals heterozygous for the c.1378A>T allele (p.Lys460Ter) compared to relatives homozygous for the normal allele, probably due to the non-secretion of the truncated protein produced by the c.1378A>T transcripts. Sequencing ANGPTL6 in a series of 94 additional index case subjects with familial IA identified three other rare coding variants in five case subjects. Overall, we detected a significant enrichment (p = 0.023) in rare coding variants within this gene among the 95 index case subjects with familial IA, compared to a reference population of 404 individuals with French ancestry. Among the 6 recruited families, 12 out of 13 (92%) individuals carrying IA also carry such variants in ANGPTL6, versus 15 out of 41 (37%) unaffected ones. We observed a higher rate of individuals with a history of high blood pressure among affected versus healthy individuals carrying ANGPTL6 variants, suggesting that ANGPTL6 could trigger cerebrovascular lesions when combined with other risk factors such as hypertension. Altogether, our results indicate that rare coding variants in ANGPTL6 are causally related to familial forms of IA. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Work-family balance by women GP specialist trainees in Slovenia: a qualitative study.

PubMed

Petek, Davorina; Gajsek, Tadeja; Petek Ster, Marija

2016-01-28

Women physicians face many challenges while balancing their many roles: doctor, specialist trainee, mother and partner. The most opportune biological time for a woman to start a family coincides with a great deal of demands and requirements at work. In this study we explored the options and capabilities of women GP specialist trainees in coordinating their family and career. This is a phenomenological qualitative research. Ten GP specialist trainees from urban and rural areas were chosen by the purposive sampling technique, and semi-structured in-depth interviews were conducted, recorded, transcribed and analysed by using thematic analysis process. Open coding and the book of codes were formed. Finally, we performed the process of code reduction by identifying the themes, which were compared, interpreted and organised in the highest analytical units--categories. One hundred fifty-five codes were identified in the analysis, which were grouped together into eleven themes. The identified themes are: types, causes and consequences of burdens, work as pleasure and positive attitude toward self, priorities, planning and help, and understanding of superiors, disburdening and changing in specialisation. The themes were grouped into four large categories: burdens, empowerment, coordination and needs for improvement. Women specialist trainees encounter intense burdens at work and home due to numerous demands and requirements during their specialisation training. In addition, there is also the issue of the work-family conflict. There are many consequences regarding burden and strain; however, burnout stands out the most. In contrast, reconciliation of work and family life and needs can be successful. The key element is empowerment of women doctors. The foremost necessary systemic solution is the reinforcement of general practitioners in primary health care and their understanding of the specialisation training scheme with more flexible possibilities for time adaptations of specialist training.

Improving coding accuracy in an academic practice.

PubMed

Nguyen, Dana; O'Mara, Heather; Powell, Robert

2017-01-01

Practice management has become an increasingly important component of graduate medical education. This applies to every practice environment; private, academic, and military. One of the most critical aspects of practice management is documentation and coding for physician services, as they directly affect the financial success of any practice. Our quality improvement project aimed to implement a new and innovative method for teaching billing and coding in a longitudinal fashion in a family medicine residency. We hypothesized that implementation of a new teaching strategy would increase coding accuracy rates among residents and faculty. Design: single group, pretest-posttest. military family medicine residency clinic. Study populations: 7 faculty physicians and 18 resident physicians participated as learners in the project. Educational intervention: monthly structured coding learning sessions in the academic curriculum that involved learner-presented cases, small group case review, and large group discussion. overall coding accuracy (compliance) percentage and coding accuracy per year group for the subjects that were able to participate longitudinally. Statistical tests used: average coding accuracy for population; paired t test to assess improvement between 2 intervention periods, both aggregate and by year group. Overall coding accuracy rates remained stable over the course of time regardless of the modality of the educational intervention. A paired t test was conducted to compare coding accuracy rates at baseline (mean (M)=26.4%, SD=10%) to accuracy rates after all educational interventions were complete (M=26.8%, SD=12%); t24=-0.127, P=.90. Didactic teaching and small group discussion sessions did not improve overall coding accuracy in a residency practice. Future interventions could focus on educating providers at the individual level.

Medical decision making: guide to improved CPT coding.

PubMed

Holt, Jim; Warsy, Ambreen; Wright, Paula

2010-04-01

The Current Procedural Terminology (CPT) coding system for office visits, which has been in use since 1995, has not been well studied, but it is generally agreed that the system contains much room for error. In fact, the available literature suggests that only slightly more than half of physicians will agree on the same CPT code for a given visit, and only 60% of professional coders will agree on the same code for a particular visit. In addition, the criteria used to assign a code are often related to the amount of written documentation. The goal of this study was to evaluate two novel methods to assess if the most appropriate CPT code is used: the level of medical decision making, or the sum of all problems mentioned by the patient during the visit. The authors-a professional coder, a residency faculty member, and a PGY-3 family medicine resident-reviewed 351 randomly selected visit notes from two residency programs in the Northeast Tennessee region for the level of documentation, the level of medical decision making, and the total number of problems addressed. The authors assigned appropriate CPT codes at each of those three levels. Substantial undercoding occurred at each of the three levels. Approximately 33% of visits were undercoded based on the written documentation. Approximately 50% of the visits were undercoded based on the level of documented medical decision making. Approximately 80% of the visits were undercoded based on the total number of problems which the patient presented during the visit. Interrater agreement was fair, and similar to that noted in other coding studies. Undercoding is not only common in a family medicine residency program but it also occurs at levels that would not be evident from a simple audit of the documentation on the visit note. Undercoding also occurs from not exploring problems mentioned by the patient and not documenting additional work that was performed. Family physicians may benefit from minor alterations in their documentation of office visit notes.

Data Collection Handbook to Support Modeling Impacts of Radioactive Material in Soil and Building Structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Charley; Kamboj, Sunita; Wang, Cheng

2015-09-01

This handbook is an update of the 1993 version of the Data Collection Handbook and the Radionuclide Transfer Factors Report to support modeling the impact of radioactive material in soil. Many new parameters have been added to the RESRAD Family of Codes, and new measurement methodologies are available. A detailed review of available parameter databases was conducted in preparation of this new handbook. This handbook is a companion document to the user manuals when using the RESRAD (onsite) and RESRAD-OFFSITE code. It can also be used for RESRAD-BUILD code because some of the building-related parameters are included in this handbook.more » The RESRAD (onsite) has been developed for implementing U.S. Department of Energy Residual Radioactive Material Guidelines. Hydrogeological, meteorological, geochemical, geometrical (size, area, depth), crops and livestock, human intake, source characteristic, and building characteristic parameters are used in the RESRAD (onsite) code. The RESRAD-OFFSITE code is an extension of the RESRAD (onsite) code and can also model the transport of radionuclides to locations outside the footprint of the primary contamination. This handbook discusses parameter definitions, typical ranges, variations, and measurement methodologies. It also provides references for sources of additional information. Although this handbook was developed primarily to support the application of RESRAD Family of Codes, the discussions and values are valid for use of other pathway analysis models and codes.« less

Review of the family Proctorenyxidae (Hymenoptera: Proctotrupoidea), with description of new species from South Korea.

PubMed

Kim, Chang-Jun; Lelej, Arkady S; Park, Bia; Lee, Jong-Wook

2016-04-11

Kozlov (1994) established a new parasitic proctotrupoid family, Renyxidae, for a single species, Renyxa incredibilis, from Primorskij Krai, in the Russian Far East. A new genus and species, Hsiufuropronia chaoi, was described from China, Beijing (Yang 1997) in the family Roproniidae. Lelej and Kozlov (1999) noticed that Renyxa was preoccupied and was initially used by Kurochkin and Slankis (1973) for a genus of flatworms (Cestoda: Litobothridae). According to Articles 39, 60 of the Code (ICZN 1999), the names of the genus and family were changed to Proctorenyxa Lelej & Kozlov, 1999 (Lelej & Kozlov 1999). He et al. (2002) transferred Hsiufuropronia from Roproniidae to Proctorenyxidae based on Yang's original description and illustrations, and synonymized Hsiufuropronia Yang under Proctorenyxa Lelej & Kozlov. Later, He and Xu (2015) proposed that the family name Proctorenyxidae should be replaced by Hsiufuroproniidae and the genera Proctonenyxa Lelej & Kozlov and Hsiufuropronia Yang should be separate. However, the replacement name Hsiufuroproniidae contradicts article 39 of the Code (ICZN 1999).

Novel human CRYGD rare variant in a Brazilian family with congenital cataract

PubMed Central

Giordano, Gabriel Gorgone; Tavares, Anderson; da Silva, Márcio José; de Vasconcellos, José Paulo Cabral; Arieta, Carlos Eduardo Leite; de Melo, Mônica Barbosa

2011-01-01

Purpose To describe a novel polymorphism in the γD-crystallin (CRYGD) gene in a Brazilian family with congenital cataract. Methods A Brazilian four-generation family was analyzed. The proband had bilateral lamellar cataract and the phenotypes were classified by slit lamp examination. Genomic DNA was extracted from peripheral blood and coding regions and intron/exon boundaries of the αA-crystallin (CRYAA), γC-crystallin (CRYGC), and CRYGD genes were amplified by polymerase chain reaction and directly sequenced. Results Sequencing of the coding regions of CRYGD showed the presence of a heterozygous A→G transversion at c.401 position, which results in the substitution of a tyrosine to a cysteine (Y134C). The polymorphism was identified in three individuals, two affected and one unaffected. Conclusions A novel rare variant in CRYGD (Y134C) was detected in a Brazilian family with congenital cataract. Because there is no segregation between the substitution and the phenotypes in this family, other genetic alterations are likely to be present. PMID:21866214

Non-Coding RNA Analysis Using the Rfam Database.

PubMed

Kalvari, Ioanna; Nawrocki, Eric P; Argasinska, Joanna; Quinones-Olvera, Natalia; Finn, Robert D; Bateman, Alex; Petrov, Anton I

2018-06-01

Rfam is a database of non-coding RNA families in which each family is represented by a multiple sequence alignment, a consensus secondary structure, and a covariance model. Using a combination of manual and literature-based curation and a custom software pipeline, Rfam converts descriptions of RNA families found in the scientific literature into computational models that can be used to annotate RNAs belonging to those families in any DNA or RNA sequence. Valuable research outputs that are often locked up in figures and supplementary information files are encapsulated in Rfam entries and made accessible through the Rfam Web site. The data produced by Rfam have a broad application, from genome annotation to providing training sets for algorithm development. This article gives an overview of how to search and navigate the Rfam Web site, and how to annotate sequences with RNA families. The Rfam database is freely available at http://rfam.org. © 2018 by John Wiley & Sons, Inc. Copyright © 2018 John Wiley & Sons, Inc.

The acoustic correlates of valence depend on emotion family.

PubMed

Belyk, Michel; Brown, Steven

2014-07-01

The voice expresses a wide range of emotions through modulations of acoustic parameters such as frequency and amplitude. Although the acoustics of individual emotions are well understood, attempts to describe the acoustic correlates of broad emotional categories such as valence have yielded mixed results. In the present study, we analyzed the acoustics of emotional valence for different families of emotion. We divided emotional vocalizations into "motivational," "moral," and "aesthetic" families as defined by the OCC (Ortony, Clore, and Collins) model of emotion. Subjects viewed emotional scenarios and were cued to vocalize congruent exclamations in response to them, for example, "Yay!" and "Damn!". Positive valence was weakly associated with high-pitched and loud vocalizations. However, valence interacted with emotion family for both pitch and amplitude. A general acoustic code for valence does not hold across families of emotion, whereas family-specific codes provide a more accurate description of vocal emotions. These findings are consolidated into a set of "rules of expression" relating vocal dimensions to emotion dimensions. Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Correlation between connexin 32 gene mutations and clinical phenotype in X-linked dominant Charcot-Marie-Tooth neuropathy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ionasescu, V.; Ionasescu, R.; Searby, C.

1996-06-14

We studied the relationship between the genotype and clinical phenotype in 27 families with dominant X-linked Charcot-Marie-Tooth (CMTX1) neuropathy. Twenty-two families showed mutations in the coding region of the connexin32 (cx32) gene. The mutations include four nonsense mutations, eight missense mutations, two medium size deletions, and one insertion. Most missense mutations showed a mild clinical phenotype (five out of eight), whereas all nonsense mutations, the larger of the two deletions, and the insertion that produced frameshifts showed severe phenotypes. Five CMTX1 families with mild clinical phenotype showed no point mutations of the cx32 gene coding region. Three of these familiesmore » showed positive genetic linkage with the markers of the Xq13.1 region. The genetic linkage of the remaining two families could not be evaluated because of their small size. 25 refs., 1 fig., 1 tab.« less

A framework for employing femtosatellites in planetary science missions, including a proposed mission concept for Titan

NASA Astrophysics Data System (ADS)

Perez, Tracie Renea Conn

Over the past 15 years, there has been a growing interest in femtosatellites, a class of tiny satellites having mass less than 100 grams. Research groups from Peru, Spain, England, Canada, and the United States have proposed femtosat designs and novel mission concepts for them. In fact, Peru made history in 2013 by releasing the first - and still only - femtosat tracked from LEO. However, femtosatellite applications in interplanetary missions have yet to be explored in detail. An interesting operations concept would be for a space probe to release numerous femtosatellites into orbit around a planetary object of interest, thereby augmenting the overall data collection capability of the mission. A planetary probe releasing hundreds of femtosats could complete an in-situ, simultaneous 3D mapping of a physical property of interest, achieving scientific investigations not possible for one probe operating alone. To study the technical challenges associated with such a mission, a conceptual mission design is proposed where femtosats are deployed from a host satellite orbiting Titan. The conceptual mission objective is presented: to study Titan's dynamic atmosphere. Then, the design challenges are addressed in turn. First, any science payload measurements that the femtosats provide are only useful if their corresponding locations can be determined. Specifically, what's required is a method of position determination for femtosatellites operating beyond Medium Earth Orbit and therefore beyond the help of GPS. A technique is presented which applies Kalman filter techniques to Doppler shift measurements, allowing for orbit determination of the femtosats. Several case studies are presented demonstrating the usefulness of this approach. Second, due to the inherit power and computational limitations in a femtosatellite design, establishing a radio link between each chipsat and the mothersat will be difficult. To provide a mathematical gain, a particular form of forward error correction (FEC) method called low-density parity-check (LDPC) codes is recommended. A specific low-complexity encoder, and accompanying decoder, have been implemented in the open-source software radio library, GNU Radio. Simulation results demonstrating bit error rate (BER) improvement are presented. Hardware for implementing the LDPC methods in a benchtop test are described and future work on this topic is suggested. Third, the power and spatial constraints of femtosatellite designs likely restrict the payload to one or two sensors. Therefore, it is desired to extract as much useful scientific data as possible from secondary sources, such as radiometric data. Estimating the atmospheric density model from different measurement sources is simulated; results are presented. The overall goal for this effort is to advance the field of miniature spacecraft-based technology and to highlight the advantages of using femtosatellites in future planetary exploration missions. By addressing several subsystem design challenges in this context, such a femtosat mission concept is one step closer to being feasible.

Performance analysis of optical wireless communication system based on two-fold turbo code

NASA Astrophysics Data System (ADS)

Chen, Jun; Huang, Dexiu; Yuan, Xiuhua

2005-11-01

Optical wireless communication (OWC) is beginning to emerge in the telecommunications market as a strategy to meet last-mile demand owing to its unique combination of features. Turbo codes have an impressive near Shannon-limit error correcting performance. Twofold turbo codes have been recently introduced as the least complex member of the multifold turbo code family. In this paper, at first, we present the mathematical model of signal and optical wireless channel with fading and bit error rate model with scintillation, then we provide a new turbo code method to use in OWC system, we can obtain a better BER curse of OWC system with twofold turbo code than with common turbo code.

Resistor-logic demultiplexers for nanoelectronics based on constant-weight codes.

PubMed

Kuekes, Philip J; Robinett, Warren; Roth, Ron M; Seroussi, Gadiel; Snider, Gregory S; Stanley Williams, R

2006-02-28

The voltage margin of a resistor-logic demultiplexer can be improved significantly by basing its connection pattern on a constant-weight code. Each distinct code determines a unique demultiplexer, and therefore a large family of circuits is defined. We consider using these demultiplexers for building nanoscale crossbar memories, and determine the voltage margin of the memory system based on a particular code. We determine a purely code-theoretic criterion for selecting codes that will yield memories with large voltage margins, which is to minimize the ratio of the maximum to the minimum Hamming distance between distinct codewords. For the specific example of a 64 × 64 crossbar, we discuss what codes provide optimal performance for a memory.

Mal-Xtract: Hidden Code Extraction using Memory Analysis

NASA Astrophysics Data System (ADS)

Lim, Charles; Syailendra Kotualubun, Yohanes; Suryadi; Ramli, Kalamullah

2017-01-01

Software packer has been used effectively to hide the original code inside a binary executable, making it more difficult for existing signature based anti malware software to detect malicious code inside the executable. A new method of written and rewritten memory section is introduced to to detect the exact end time of unpacking routine and extract original code from packed binary executable using Memory Analysis running in an software emulated environment. Our experiment results show that at least 97% of the original code from the various binary executable packed with different software packers could be extracted. The proposed method has also been successfully extracted hidden code from recent malware family samples.

Attachment and Family Processes in Children's Psychological Adjustment in Middle Childhood.

PubMed

Demby, Kimberly P; Riggs, Shelley A; Kaminski, Patricia L

2017-03-01

This study examined the links between parent-child attachment, whole family interaction patterns, and child emotional adjustment and adaptability in a sample of 86 community families with children between the ages of 8 and 11 years. Family interactions were observed and coded with the System for Coding Interactions and Family Functioning (SCIFF; Lindahl, 2001). Both parents and each target child completed the appropriate form of the Behavior Assessment System for Children-2nd Edition (BASC-2; Reynolds & Kamphaus, 2004). Target children also completed the Children's Coping Strategies Questionnaire (CCSQ; Yunger, Corby, & Perry, 2005). Hierarchical multiple regressions indicated that Secure mother-child attachment was a robust predictor of children's emotional symptoms, but father-child attachment strategies were not significant independent predictors. Positive Affect in family interactions significantly increased the amount of variance accounted for in children's emotional symptoms. In addition, Family Cohesion and Positive Affect moderated the relationship between father-child attachment and children's emotional symptoms. When data from all BASC-2 informants (mother, father, child) were considered simultaneously and multidimensional constructs were modeled, mother-child security directly predicted children's adjustment and adaptive skills, but the influence of father-child security was fully mediated through positive family functioning. Results of the current study support the utility of considering dyadic attachment and family interaction patterns conjointly when conceptualizing and fostering positive emotional and behavioral outcomes in children. © 2015 Family Process Institute.

Parallel Demand-Withdraw Processes in Family Therapy for Adolescent Drug Abuse

PubMed Central

Rynes, Kristina N.; Rohrbaugh, Michael J.; Lebensohn-Chialvo, Florencia; Shoham, Varda

2013-01-01

Isomorphism, or parallel process, occurs in family therapy when patterns of therapist-client interaction replicate problematic interaction patterns within the family. This study investigated parallel demand-withdraw processes in Brief Strategic Family Therapy (BSFT) for adolescent drug abuse, hypothesizing that therapist-demand/adolescent-withdraw interaction (TD/AW) cycles observed early in treatment would predict poor adolescent outcomes at follow-up for families who exhibited entrenched parent-demand/adolescent-withdraw interaction (PD/AW) before treatment began. Participants were 91 families who received at least 4 sessions of BSFT in a multi-site clinical trial on adolescent drug abuse (Robbins et al., 2011). Prior to receiving therapy, families completed videotaped family interaction tasks from which trained observers coded PD/AW. Another team of raters coded TD/AW during two early BSFT sessions. The main dependent variable was the number of drug use days that adolescents reported in Timeline Follow-Back interviews 7 to 12 months after family therapy began. Zero-inflated Poisson (ZIP) regression analyses supported the main hypothesis, showing that PD/AW and TD/AW interacted to predict adolescent drug use at follow-up. For adolescents in high PD/AW families, higher levels of TD/AW predicted significant increases in drug use at follow-up, whereas for low PD/AW families, TD/AW and follow-up drug use were unrelated. Results suggest that attending to parallel demand-withdraw processes in parent/adolescent and therapist/adolescent dyads may be useful in family therapy for substance-using adolescents. PMID:23438248

New quantum codes constructed from quaternary BCH codes

NASA Astrophysics Data System (ADS)

Xu, Gen; Li, Ruihu; Guo, Luobin; Ma, Yuena

2016-10-01

In this paper, we firstly study construction of new quantum error-correcting codes (QECCs) from three classes of quaternary imprimitive BCH codes. As a result, the improved maximal designed distance of these narrow-sense imprimitive Hermitian dual-containing quaternary BCH codes are determined to be much larger than the result given according to Aly et al. (IEEE Trans Inf Theory 53:1183-1188, 2007) for each different code length. Thus, families of new QECCs are newly obtained, and the constructed QECCs have larger distance than those in the previous literature. Secondly, we apply a combinatorial construction to the imprimitive BCH codes with their corresponding primitive counterpart and construct many new linear quantum codes with good parameters, some of which have parameters exceeding the finite Gilbert-Varshamov bound for linear quantum codes.

Constructions for finite-state codes

NASA Technical Reports Server (NTRS)

Pollara, F.; Mceliece, R. J.; Abdel-Ghaffar, K.

1987-01-01

A class of codes called finite-state (FS) codes is defined and investigated. These codes, which generalize both block and convolutional codes, are defined by their encoders, which are finite-state machines with parallel inputs and outputs. A family of upper bounds on the free distance of a given FS code is derived from known upper bounds on the minimum distance of block codes. A general construction for FS codes is then given, based on the idea of partitioning a given linear block into cosets of one of its subcodes, and it is shown that in many cases the FS codes constructed in this way have a d sub free which is as large as possible. These codes are found without the need for lengthy computer searches, and have potential applications for future deep-space coding systems. The issue of catastropic error propagation (CEP) for FS codes is also investigated.

Topic models: A novel method for modeling couple and family text data

PubMed Central

Atkins, David C.; Rubin, Tim N.; Steyvers, Mark; Doeden, Michelle A.; Baucom, Brian R.; Christensen, Andrew

2012-01-01

Couple and family researchers often collect open-ended linguistic data – either through free response questionnaire items or transcripts of interviews or therapy sessions. Because participant's responses are not forced into a set number of categories, text-based data can be very rich and revealing of psychological processes. At the same time it is highly unstructured and challenging to analyze. Within family psychology analyzing text data typically means applying a coding system, which can quantify text data but also has several limitations, including the time needed for coding, difficulties with inter-rater reliability, and defining a priori what should be coded. The current article presents an alternative method for analyzing text data called topic models (Steyvers & Griffiths, 2006), which has not yet been applied within couple and family psychology. Topic models have similarities with factor analysis and cluster analysis in that topic models identify underlying clusters of words with semantic similarities (i.e., the “topics”). In the present article, a non-technical introduction to topic models is provided, highlighting how these models can be used for text exploration and indexing (e.g., quickly locating text passages that share semantic meaning) and how output from topic models can be used to predict behavioral codes or other types of outcomes. Throughout the article a collection of transcripts from a large couple therapy trial (Christensen et al., 2004) is used as example data to highlight potential applications. Practical resources for learning more about topic models and how to apply them are discussed. PMID:22888778

Topic models: a novel method for modeling couple and family text data.

PubMed

Atkins, David C; Rubin, Timothy N; Steyvers, Mark; Doeden, Michelle A; Baucom, Brian R; Christensen, Andrew

2012-10-01

Couple and family researchers often collect open-ended linguistic data-either through free-response questionnaire items, or transcripts of interviews or therapy sessions. Because participants' responses are not forced into a set number of categories, text-based data can be very rich and revealing of psychological processes. At the same time, it is highly unstructured and challenging to analyze. Within family psychology, analyzing text data typically means applying a coding system, which can quantify text data but also has several limitations, including the time needed for coding, difficulties with interrater reliability, and defining a priori what should be coded. The current article presents an alternative method for analyzing text data called topic models (Steyvers & Griffiths, 2006), which has not yet been applied within couple and family psychology. Topic models have similarities to factor analysis and cluster analysis in that they identify underlying clusters of words with semantic similarities (i.e., the "topics"). In the present article, a nontechnical introduction to topic models is provided, highlighting how these models can be used for text exploration and indexing (e.g., quickly locating text passages that share semantic meaning) and how output from topic models can be used to predict behavioral codes or other types of outcomes. Throughout the article, a collection of transcripts from a large couple-therapy trial (Christensen et al., 2004) is used as example data to highlight potential applications. Practical resources for learning more about topic models and how to apply them are discussed. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

The Base 32 Method: An Improved Method for Coding Sibling Constellations.

ERIC Educational Resources Information Center

Perfetti, Lawrence J. Carpenter

1990-01-01

Offers new sibling constellation coding method (Base 32) for genograms using binary and base 32 numbers that saves considerable microcomputer memory. Points out that new method will result in greater ability to store and analyze larger amounts of family data. (Author/CM)

Distillation with Sublogarithmic Overhead.

PubMed

Hastings, Matthew B; Haah, Jeongwan

2018-02-02

It has been conjectured that, for any distillation protocol for magic states for the T gate, the number of noisy input magic states required per output magic state at output error rate ε is Ω[log(1/ε)]. We show that this conjecture is false. We find a family of quantum error correcting codes of parameters ⟦∑[under i=w+1][over m](m/i),∑[under i=0][over w](m/i),∑[under i=w+1][over r+1](r+1/i)⟧ for any integers m>2r, r>w≥0, by puncturing quantum Reed-Muller codes. When m>νr, our code admits a transversal logical gate at the νth level of Clifford hierarchy. In a distillation protocol for magic states at the level ν=3 (T gate), the ratio of input to output magic states is O(log^{γ}(1/ε)), where γ=log(n/k)/log(d)<0.678 for some m, r, w. The smallest code in our family for which γ<1 is on ≈2^{58} qubits.

Transversal Clifford gates on folded surface codes

DOE PAGES

Moussa, Jonathan E.

2016-10-12

Surface and color codes are two forms of topological quantum error correction in two spatial dimensions with complementary properties. Surface codes have lower-depth error detection circuits and well-developed decoders to interpret and correct errors, while color codes have transversal Clifford gates and better code efficiency in the number of physical qubits needed to achieve a given code distance. A formal equivalence exists between color codes and folded surface codes, but it does not guarantee the transferability of any of these favorable properties. However, the equivalence does imply the existence of constant-depth circuit implementations of logical Clifford gates on folded surfacemore » codes. We achieve and improve this result by constructing two families of folded surface codes with transversal Clifford gates. This construction is presented generally for qudits of any dimension. Lastly, the specific application of these codes to universal quantum computation based on qubit fusion is also discussed.« less

Family acholeplasmataceae (including phytoplasmas)

USDA-ARS?s Scientific Manuscript database

The family Acholeplasmataceae was originally established to accommodate the genus Acholeplasma, comprising the mollicutes that could be cultivated without the supplement of cholesterol and that use UGA as a stop codon instead of coding for tryptophan. It was later shown that the phytoplasmas, a larg...

22 CFR 226.42 - Codes of conduct.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.42 Codes of conduct. The recipient shall... immediate family, his or her partner, or an organization which employs or is about to employ any of the...

Disjointness of Stabilizer Codes and Limitations on Fault-Tolerant Logical Gates

NASA Astrophysics Data System (ADS)

Jochym-O'Connor, Tomas; Kubica, Aleksander; Yoder, Theodore J.

2018-04-01

Stabilizer codes are among the most successful quantum error-correcting codes, yet they have important limitations on their ability to fault tolerantly compute. Here, we introduce a new quantity, the disjointness of the stabilizer code, which, roughly speaking, is the number of mostly nonoverlapping representations of any given nontrivial logical Pauli operator. The notion of disjointness proves useful in limiting transversal gates on any error-detecting stabilizer code to a finite level of the Clifford hierarchy. For code families, we can similarly restrict logical operators implemented by constant-depth circuits. For instance, we show that it is impossible, with a constant-depth but possibly geometrically nonlocal circuit, to implement a logical non-Clifford gate on the standard two-dimensional surface code.

The Literature on Military Families, 1980: An Annotated Bibliography.

DTIC Science & Technology

1980-08-01

re- search results are useful in planning. Principles to be considered in the future planning, management , and dissemination of family research in the...Derr, C. B. Managing marriage/ family issues across career stages: the case of the U.S. Naval officers. Unpublished manuscript, Depart- ment...Report No. 2, NP554-79-003. Arlington VA: Office of Naval Research (Code 454), 1979. See: Derr, C. B. Managing marriage/ family issues across career stages

Continuing the School Choice March: Policies to Promote Family K-12 Education Investment. Backgrounder. No. 2683

ERIC Educational Resources Information Center

Burke, Lindsey M.; Sheffield, Rachel

2012-01-01

Coverdell education savings accounts (ESAs), created through the federal tax code, allow families to save money tax-free for K-12 and higher education expenses. Lifting the cap on contributions to Coverdell accounts would provide greater access to school choice options by allowing families to invest more money in their children's education.…

Associations of Home and Classroom Environments with Head Start Children's Code-Related and Oral Language Skills

ERIC Educational Resources Information Center

Han, Jisu; Schlieber, Marisa; Gregory, Bradley

2017-01-01

This study used data from the Head Start Family and Child Experiences Survey (FACES) 2009 4-year-old cohort to examine associations among family characteristics, home and classroom environments, and the emergent literacy skills of Head Start children. Results from hierarchical linear models suggest that both family and classroom contexts play a…

Development of new two-dimensional spectral/spatial code based on dynamic cyclic shift code for OCDMA system

NASA Astrophysics Data System (ADS)

Jellali, Nabiha; Najjar, Monia; Ferchichi, Moez; Rezig, Houria

2017-07-01

In this paper, a new two-dimensional spectral/spatial codes family, named two dimensional dynamic cyclic shift codes (2D-DCS) is introduced. The 2D-DCS codes are derived from the dynamic cyclic shift code for the spectral and spatial coding. The proposed system can fully eliminate the multiple access interference (MAI) by using the MAI cancellation property. The effect of shot noise, phase-induced intensity noise and thermal noise are used to analyze the code performance. In comparison with existing two dimensional (2D) codes, such as 2D perfect difference (2D-PD), 2D Extended Enhanced Double Weight (2D-Extended-EDW) and 2D hybrid (2D-FCC/MDW) codes, the numerical results show that our proposed codes have the best performance. By keeping the same code length and increasing the spatial code, the performance of our 2D-DCS system is enhanced: it provides higher data rates while using lower transmitted power and a smaller spectral width.

Income Tax Guide.

ERIC Educational Resources Information Center

Exceptional Parent, 1979

1979-01-01

The article outlines changes in the Internal Revenue Code with direct and general bearing on taxpayers with disabled family members. Amendments to the Internal Revenue Code included in the Revenue Act of 1978 are described in terms of credits, deductions, and exemptions; and suggestions are offered regarding record keeping, tax return audits, and…

Novel folliculin (FLCN) mutation and familial spontaneous pneumothorax.

PubMed

Zhu, J-F; Shen, X-Q; Zhu, F; Tian, L

2017-01-01

Familial spontaneous pneumothorax is one of the characteristics of Birt-Hogg-Dubé syndrome (BHDS), which is an autosomal dominant disease caused by the mutation of folliculin (FLCN). To investigate the mutation of FLCN gene in a familial spontaneous pneumothorax. Prospective case study. Clinical and genetic data of a Chinese family with four patients who presented spontaneous pneumothorax in the absence of skin lesions or renal tumors were collected. CT scan of patient's lung was applied for observation of pneumothorax. DNA sequencing of the coding exons (4-14 exons) of FLCN was performed for all 11 members of the family and 100 unrelated healthy controls. CT scan of patient's lung showed spontaneous pneumothorax. A mutation (c. 510C > G) that leads to a premature stop codon (p. Y170X) was found in the proband using DNA sequencing of coding exons (4-14 exons) of FLCN. This mutation was also observed in the other affected members of the family. A nonsense mutation of FLCN was found in a spontaneous pneumothorax family. Our results expand the mutational spectrum of FLCN in patients with BHDS. © The Author 2016. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A Component-Centered Meta-Analysis of Family-Based Prevention Programs for Adolescent Substance Use

PubMed Central

Roseth, Cary J.; Fosco, Gregory M.; Lee, You-kyung; Chen, I-Chien

2016-01-01

Although research has documented the positive effects of family-based prevention programs, the field lacks specific information regarding why these programs are effective. The current study summarized the effects of family-based programs on adolescent substance use using a component-based approach to meta-analysis in which we decomposed programs into a set of key topics or components that were specifically addressed by program curricula (e.g., parental monitoring/behavior management, problem solving, positive family relations, etc.). Components were coded according to the amount of time spent on program services that targeted youth, parents, and the whole family; we also coded effect sizes across studies for each substance-related outcome. Given the nested nature of the data, we used hierarchical linear modeling to link program components (Level 2) with effect sizes (Level 1). The overall effect size across programs was .31, which did not differ by type of substance. Youth-focused components designed to encourage more positive family relationships and a positive orientation toward the future emerged as key factors predicting larger than average effect sizes. Our results suggest that, within the universe of family-based prevention, where components such as parental monitoring/behavior management are almost universal, adding or expanding certain youth-focused components may be able to enhance program efficacy. PMID:27064553

Calculations of the Performance of Explosive Impulse Generators

DTIC Science & Technology

1979-08-01

low impedance material such as lexan or some other plastic between the tungsten and the titanium, the stress is reduced even further. As we said...codes modeled after the HEMP family of codes^ cur- rently in use at the Lawrence Livermore Laboratory. The codes have a broad range of capabilities...for problems involving the dynamics of fluid and solid continua. They contain a full range of material property models including elastic- plastic flow

Effects of family presence on the content and dynamics of the clinical encounter among diabetic patients.

PubMed

Katerndahl, David; Parchman, Michael

2013-12-01

Primary care visits often include a family member or friend. The purpose of this study was to determine the effect of the presence of a family member on the visit content and dynamics among diabetic patients in Family Medicine settings. Encounters of patients with type 2 diabetes from 20 primary care clinics were audio-recorded and transcribed. Encounters were coded using the Davis Observation Codes, classifying content into 20 different categories at 15-second intervals. A random sample of 30 patients with family members was selected; 30 encounters in which no family was present were then matched to the randomly selected patients so that they would be similar group-wise in A1C level, length of visit, level of distress and discussion of non-patient family problems for analysis using orbital decomposition, an analytic technique based on symbolic dynamics in which categorical time series data are used to identify amount of complexity present and recurrent patterns of strings. Visits were more linear if family members were present. When family members were present, 90-second strings of preventive services and evaluation/feedback were observed while 90 seconds of exercise discussion occurred when they were absent. Visits without family members tended to include more chatting, compliance discussion and nutrition counselling, while those with family members included more patient questions and evaluation/feedback. Finally, the sequence of history-to-planning-to-evaluation was observed when family were absent, but evaluation-to-planning-to-history when family were present. The presence of a family member was associated with increased linearity and recurrent patterns that focused more on evaluation/feedback, preventive services, and patient questions, and less on chatting, exercise, compliance and nutrition in diabetic encounters. © 2013 John Wiley & Sons Ltd.

Examining mealtime behaviors in families of young children with type 1 diabetes on intensive insulin therapy.

PubMed

Patton, Susana R; Dolan, Lawrence M; Smith, Laura B; Brown, Morton B; Powers, Scott W

2013-12-01

This study examined mealtime behaviors in families of young children with type 1 diabetes (T1DM) on intensive insulin therapy. Behaviors were compared to published data for children on conventional therapy and examined for correlations with glycemic control. Thirty-nine families participated and had at least three home meals videotaped while children wore a continuous glucose monitor. Videotaped meals were coded for parent, child, and child eating behaviors using a valid coding system. A group difference was found for child request for food only. There were also associations found between children's glycemic control and child play and away. However, no associations were found between parent and child behaviors within meals and children's corresponding post-prandial glycemic control. Results reinforce existing research indicating that mealtime behavior problems exist for families of young children even in the context of intensive therapy and that some child behaviors may relate to glycemic control. © 2013.

The PE/PPE multigene family codes for virulence factors and is a possible source of mycobacterial antigenic variation: perhaps more?

PubMed

Akhter, Yusuf; Ehebauer, Matthias T; Mukhopadhyay, Sangita; Hasnain, Seyed E

2012-01-01

The PE/PPE multigene family codes for approximately 10% of the Mycobacterium tuberculosis proteome and is encoded by 176 open reading frames. These proteins possess, and have been named after, the conserved proline-glutamate (PE) or proline-proline-glutamate (PPE) motifs at their N-terminus. Their genes have a conserved structure and repeat motifs that could be a potential source of antigenic variation in M. tuberculosis. PE/PPE genes are scattered throughout the genome and PE/PPE pairs are usually encoded in bicistronic operons although this is not universally so. This gene family has evolved by specific gene duplication events. PE/PPE proteins are either secreted or localized to the cell surface. Several are thought to be virulence factors, which participate in evasion of the host immune response. This review summarizes the current knowledge about the gene family in order to better understand its biological function. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

New nonbinary quantum codes with larger distance constructed from BCH codes over 𝔽q2

NASA Astrophysics Data System (ADS)

Xu, Gen; Li, Ruihu; Fu, Qiang; Ma, Yuena; Guo, Luobin

2017-03-01

This paper concentrates on construction of new nonbinary quantum error-correcting codes (QECCs) from three classes of narrow-sense imprimitive BCH codes over finite field 𝔽q2 (q ≥ 3 is an odd prime power). By a careful analysis on properties of cyclotomic cosets in defining set T of these BCH codes, the improved maximal designed distance of these narrow-sense imprimitive Hermitian dual-containing BCH codes is determined to be much larger than the result given according to Aly et al. [S. A. Aly, A. Klappenecker and P. K. Sarvepalli, IEEE Trans. Inf. Theory 53, 1183 (2007)] for each different code length. Thus families of new nonbinary QECCs are constructed, and the newly obtained QECCs have larger distance than those in previous literature.

Comparison of the protein-coding gene content of Chlamydia trachomatis and Protochlamydia amoebophila using a Raspberry Pi computer.

PubMed

Robson, James F; Barker, Daniel

2015-10-13

To demonstrate the bioinformatics capabilities of a low-cost computer, the Raspberry Pi, we present a comparison of the protein-coding gene content of two species in phylum Chlamydiae: Chlamydia trachomatis, a common sexually transmitted infection of humans, and Candidatus Protochlamydia amoebophila, a recently discovered amoebal endosymbiont. Identifying species-specific proteins and differences in protein families could provide insights into the unique phenotypes of the two species. Using a Raspberry Pi computer, sequence similarity-based protein families were predicted across the two species, C. trachomatis and P. amoebophila, and their members counted. Examples include nine multi-protein families unique to C. trachomatis, 132 multi-protein families unique to P. amoebophila and one family with multiple copies in both. Most families unique to C. trachomatis were polymorphic outer-membrane proteins. Additionally, multiple protein families lacking functional annotation were found. Predicted functional interactions suggest one of these families is involved with the exodeoxyribonuclease V complex. The Raspberry Pi computer is adequate for a comparative genomics project of this scope. The protein families unique to P. amoebophila may provide a basis for investigating the host-endosymbiont interaction. However, additional species should be included; and further laboratory research is required to identify the functions of unknown or putative proteins. Multiple outer membrane proteins were found in C. trachomatis, suggesting importance for host evasion. The tyrosine transport protein family is shared between both species, with four proteins in C. trachomatis and two in P. amoebophila. Shared protein families could provide a starting point for discovery of wide-spectrum drugs against Chlamydiae.

Meaning of Pharmacological Treatment for Families of People With Depression.

PubMed

Vedana, Kelly Graziani Giacchero; Magrini, Daniel Fernando; Souza, Jacqueline de; Zanetti, Ana Carolina Guidorizzi; Miasso, Adriana Inocenti; Telles Filho, Paulo Celso Prado; Borges, Tatiana Longo

2016-01-01

Medication adherence is related to patient satisfaction with family support. This research aimed to understand the meaning of pharmacotherapy to families of people with major depressive disorder. This qualitative study employed Grounded Theory and Symbolic Interactionism. Seventeen families of people with depression from a Brazilian clinic were included. Data was collected from 2013 to 2014, using open interviews, which were analyzed by open, axial, and selective coding. Medication represented "Tranquility and worry" because it re-established tranquility in family routine, but generated concerns. Thus, families were conflicted and ambivalent about medications, and they interfered with the promotion or impairment of adherence.

10 CFR 434.101 - Scope.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 3 2011-01-01 2011-01-01 false Scope. 434.101 Section 434.101 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL... to new Federal multi-family high rise residential buildings and new Federal commercial buildings, for...

Quantum computing with Majorana fermion codes

NASA Astrophysics Data System (ADS)

Litinski, Daniel; von Oppen, Felix

2018-05-01

We establish a unified framework for Majorana-based fault-tolerant quantum computation with Majorana surface codes and Majorana color codes. All logical Clifford gates are implemented with zero-time overhead. This is done by introducing a protocol for Pauli product measurements with tetrons and hexons which only requires local 4-Majorana parity measurements. An analogous protocol is used in the fault-tolerant setting, where tetrons and hexons are replaced by Majorana surface code patches, and parity measurements are replaced by lattice surgery, still only requiring local few-Majorana parity measurements. To this end, we discuss twist defects in Majorana fermion surface codes and adapt the technique of twist-based lattice surgery to fermionic codes. Moreover, we propose a family of codes that we refer to as Majorana color codes, which are obtained by concatenating Majorana surface codes with small Majorana fermion codes. Majorana surface and color codes can be used to decrease the space overhead and stabilizer weight compared to their bosonic counterparts.

Testing Quick Response (QR) Codes as an Innovation to Improve Feedback Among Geographically-Separated Clerkship Sites.

PubMed

Snyder, Matthew J; Nguyen, Dana R; Womack, Jasmyne J; Bunt, Christopher W; Westerfield, Katie L; Bell, Adriane E; Ledford, Christy J W

2018-03-01

Collection of feedback regarding medical student clinical experiences for formative or summative purposes remains a challenge across clinical settings. The purpose of this study was to determine whether the use of a quick response (QR) code-linked online feedback form improves the frequency and efficiency of rater feedback. In 2016, we compared paper-based feedback forms, an online feedback form, and a QR code-linked online feedback form at 15 family medicine clerkship sites across the United States. Outcome measures included usability, number of feedback submissions per student, number of unique raters providing feedback, and timeliness of feedback provided to the clerkship director. The feedback method was significantly associated with usability, with QR code scoring the highest, and paper second. Accessing feedback via QR code was associated with the shortest time to prepare feedback. Across four rotations, separate repeated measures analyses of variance showed no effect of feedback system on the number of submissions per student or the number of unique raters. The results of this study demonstrate that preceptors in the family medicine clerkship rate QR code-linked feedback as a high usability platform. Additionally, this platform resulted in faster form completion than paper or online forms. An overarching finding of this study is that feedback forms must be portable and easily accessible. Potential implementation barriers and the social norm for providing feedback in this manner need to be considered.

Patient safety principles in family medicine residency accreditation standards and curriculum objectives

PubMed Central

Kassam, Aliya; Sharma, Nishan; Harvie, Margot; O’Beirne, Maeve; Topps, Maureen

2016-01-01

Abstract Objective To conduct a thematic analysis of the College of Family Physicians of Canada’s (CFPC’s) Red Book accreditation standards and the Triple C Competency-based Curriculum objectives with respect to patient safety principles. Design Thematic content analysis of the CFPC’s Red Book accreditation standards and the Triple C curriculum. Setting Canada. Main outcome measures Coding frequency of the patient safety principles (ie, patient engagement; respectful, transparent relationships; complex systems; a just and trusting culture; responsibility and accountability for actions; and continuous learning and improvement) found in the analyzed CFPC documents. Results Within the analyzed CFPC documents, the most commonly found patient safety principle was patient engagement (n = 51 coding references); the least commonly found patient safety principles were a just and trusting culture (n = 5 coding references) and complex systems (n = 5 coding references). Other patient safety principles that were uncommon included responsibility and accountability for actions (n = 7 coding references) and continuous learning and improvement (n = 12 coding references). Conclusion Explicit inclusion of patient safety content such as the use of patient safety principles is needed for residency training programs across Canada to ensure the full spectrum of care is addressed, from community-based care to acute hospital-based care. This will ensure a patient safety culture can be cultivated from residency and sustained into primary care practice. PMID:27965349

[Amendment of the Kodeks rodzinny i opiekuńczy (Family and Guardianship Code), Chapter I. "Origin of a child"--some remarks of an expert witness in forensic genetics].

PubMed

Raczek, Ewa

2009-01-01

On June 13, 2009, the new Family and Guardianship Code came into effect. Many important modifications were implemented to Chapter I. "Origin of a child", the issue being of special importance in the work of a forensic geneticist. Those changes are related not only to arguableness of the fatherhood of both types--the one that is judged in lawsuit of denial of the fatherhood and that in which ineffectiveness of paternity is recognized--but for the first time they also demand on maternity testing. The Code defines who--according to Polish law--is a mother to a child and on this base states motherhood. In consequence, the main legal maxim Mater semper certa est, which has existed since Ancient Rome times is now annulled. The paper presents some remarks of an expert witness on the introduced changes.

American School Counselor Association Ethical Code Changes Relevant to Family Work

ERIC Educational Resources Information Center

Bodenhorn, Nancy

2005-01-01

Professional organizations regularly review and revise their codes of ethics. The American School Counselor Association (ASCA) completed this task in June 2004. At the 2004 national conference, the leadership team, consisting of state presidents, past presidents, and president elects, voted to adopt the changes. These changes, as outlined in Table…

Chromosome mapping of the human arrestin (SAG), {beta}-arrestin 2 (ARRB2), and {beta}-adrenergic receptor kinase 2 (ADRBK2) genes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calabrese, G.; Sallese, M.; Stornaiuolo, A.

1994-09-01

Two types of proteins play a major role in determining homologous desensitization of G-coupled receptors: {beta}-adrenergic receptor kinase ({beta}ARK), which phosphorylates the agonist-occupied receptor and its functional cofactor, {beta}-arrestin. Both {beta}ARK and {beta}-arrestin are members of multigene families. The family of G-protein-coupled receptor kinases includes rhodopsin kinase, {beta}ARK1, {beta}ARK2, IT11-A (GRK4), GRK5, and GRK6. The arrestin/{beta}-arrestin gene family includes arrestin (also known as S-antigen), {beta}-arrestin 1, and {beta}-arrestin 2. Here we report the chromosome mapping of the human genes for arrestin (SAG), {beta}arrestin 2 (ARRB2), and {beta}ARK2 (ADRBK2) by fluorescence in situ hybridization (FISH). FISH results confirmed the assignment ofmore » the gene coding for arrestin (SAG) to chromosome 2 and allowed us to refine its localization to band q37. The gene coding for {beta}-arrestin 2 (ARRB2) was mapped to chromosome 17p13 and that coding for {beta}ARK2 (ADRBK2) to chromosome 22q11. 17 refs., 1 fig.« less

Genomic structure of two ras family genes in the slime mold Physarum polycephalum.

PubMed

Trzcińska-Danielewicz, Joanna; Kozlowski, Piotr; Gierdal, Katarzyna; Wiejak, Jolanta; Jagielski, Adam; Toczko, Kazimierz; Fronk, Jan

2002-08-01

Genomic structure of two Physarum polycephalum ras family genes, Ppras2 and Pprap1, has been determined, including the upstream region of the latter. The genes are interrupted by three and four introns, respectively. The first intron of Ppras2 has the same location within the coding sequence as the first intron in another ras homolog from this organism, Ppras1 [Trzcińska-Danielewicz, J., Kozlowski, P., and Toczko, K. (1996). "Cloning and genomic sequence of the Physarum polycephalum Ppras1 gene, a homologue of the ras protooncogene", Gene 169, pp. 143-144]. All introns, ranging from 53 to ca. 460 base pairs, have the canonical 5' and 3' ends, are greatly enriched in pyrimidines in the coding strand and have frequent pyrimidines-only tracts. These latter features seem to be responsible for the difficulties in cloning and sequencing of parts of these genes. Short sequences shared with P. polycephalum transposon-like repeats are common in the introns, indicating a possible role of transposition in intron evolution. In all three ras family genes phase zero introns are located mostly between sequences coding for regular protein secondary structure elements.

Manifestations of poverty and birthrates among young teenagers in California zip code areas.

PubMed

Kirby, D; Coyle, K; Gould, J B

2001-01-01

Given that many communities are implementing community-wide initiatives to reduce teenage pregnancy or childbearing, it is important to understand the effects of a community's characteristics on adolescent birthrates. Data from the 1990 census and from California birth certificates were obtained for zip codes in California. Regression analyses were conducted on data from zip code areas with at least 200 females aged 15-17 between 1991 and 1996, to predict the effects of race and ethnicity marital status, education, employment, income and poverty, and housing on birthrates among young teenagers. In bivariate analyses, the proportion of families living below poverty level within a zip code was highly related to the birthrate among young teenagers in that zip code (r=.80, p<.001). In multivariate analyses, which controlled for some of the correlates of family poverty level, the proportion of families living below poverty level remained by far the most important predictor of the birthrate among young teenagers (b=1.54), followed by the proportion of adults aged 25 or older who have a college education (b=-0.80). Race and ethnicity were only weakly related to birthrate. In all three racial and ethnic groups, poverty and education were significantly related to birthrate, but the effect of college education was greater among Hispanics (b=-2.98) than among either non-Hispanic whites (b=-0.53) or blacks (b=-1.12). Male employment and unemployment and female unemployment were highly related to the birthrate among young teenagers in some racial or ethnic groups, but not in others. Multiple manifestations of poverty, including poverty itself, low levels of education and employment, and high levels of unemployment, may have a large impact upon birthrates among young teenagers. Addressing some of these issues could substantially reduce childbearing among young adolescents.

Partial sequence homogenization in the 5S multigene families may generate sequence chimeras and spurious results in phylogenetic reconstructions.

PubMed

Galián, José A; Rosato, Marcela; Rosselló, Josep A

2014-03-01

Multigene families have provided opportunities for evolutionary biologists to assess molecular evolution processes and phylogenetic reconstructions at deep and shallow systematic levels. However, the use of these markers is not free of technical and analytical challenges. Many evolutionary studies that used the nuclear 5S rDNA gene family rarely used contiguous 5S coding sequences due to the routine use of head-to-tail polymerase chain reaction primers that are anchored to the coding region. Moreover, the 5S coding sequences have been concatenated with independent, adjacent gene units in many studies, creating simulated chimeric genes as the raw data for evolutionary analysis. This practice is based on the tacitly assumed, but rarely tested, hypothesis that strict intra-locus concerted evolution processes are operating in 5S rDNA genes, without any empirical evidence as to whether it holds for the recovered data. The potential pitfalls of analysing the patterns of molecular evolution and reconstructing phylogenies based on these chimeric genes have not been assessed to date. Here, we compared the sequence integrity and phylogenetic behavior of entire versus concatenated 5S coding regions from a real data set obtained from closely related plant species (Medicago, Fabaceae). Our results suggest that within arrays sequence homogenization is partially operating in the 5S coding region, which is traditionally assumed to be highly conserved. Consequently, concatenating 5S genes increases haplotype diversity, generating novel chimeric genotypes that most likely do not exist within the genome. In addition, the patterns of gene evolution are distorted, leading to incorrect haplotype relationships in some evolutionary reconstructions.

The O*Net Jobs Classification System: A Primer for Family Researchers

ERIC Educational Resources Information Center

Crouter, Ann C.; Lanza, Stephanie T.; Pirretti, Amy; Goodman, W. Benjamin; Neebe, Eloise

2006-01-01

We introduce family researchers to the Occupational Information Network, or O*Net, an electronic database on the work characteristics of over 950 occupations. The paper here is a practical primer that covers data collection, selecting occupational characteristics, coding occupations, scale creation, and construct validity, with empirical…

Marriage and Family Counseling: Ethics in Context

ERIC Educational Resources Information Center

Southern, Stephen; Smith, Robert L.; Oliver, Marvarene

2005-01-01

Codes of ethics typically provide rules and guidelines for best practices in marriage and family counseling. An emerging model for ethical decision making emphasizes the ethics of virtues and aspirations. Exploring fundamental models of helping, as well as contemporary issues in community systems, affords context for examining the professional…

Ethical Responsibilities in Training Marriage and Family Counselors

ERIC Educational Resources Information Center

Levitt, Dana Heller

2004-01-01

Graduate programs in marriage and family counseling must adhere to ethical codes and standards for training students. A question arises concerning the amount of specialized training that should be included within the larger counselor education discipline. This article addresses the standards for training and competence as set forth by the Council…

Autonomy and Relatedness in Inner-City Families of Substance Abusing Adolescents

ERIC Educational Resources Information Center

Samuolis, Jessica; Hogue, Aaron; Dauber, Sarah; Liddle, Howard A.

2006-01-01

This study examined parent-adolescent autonomous-relatedness functioning in inner-city, ethnic minority families of adolescents exhibiting drug abuse and related problem behaviors. Seventy-four parent-adolescent dyads completed a structured interaction task prior to the start of treatment that was coded using an established autonomous-relatedness…

10 CFR 434.515 - Receptacles.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Receptacles. 434.515 Section 434.515 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL... Hotel/Motel 0.25 Restaurant 0.1 Health 1.0 Multi-family High Rise Residential Included in Lights and...

10 CFR 434.513 - Occupancy.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Occupancy. 434.513 Section 434.513 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL... 100 Health/Institutional 200 Multi-family High-rise Residential 2 per unit . 1 1 Heat generation: Btu...

10 CFR 434.511 - Orientation and shape.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Orientation and shape. 434.511 Section 434.511 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE... ft. except for dwelling units in hotels/motels and multi-family high-rise residential buildings where...

Attachment-Based Family Therapy: "Adherence" and Differentiation

ERIC Educational Resources Information Center

Diamond, Gary M.; Diamond, Guy S.; Hogue, Aaron

2007-01-01

This study examined the fidelity of attachment-based family therapy (ABFT) for depressed adolescents. Trained observers used the therapist behavior rating scale (3rd version) to code therapist behaviors in 45 sessions of ABFT and 45 sessions each from two empirically based treatments for adolescent substance abusers: multidimensional family…

Family Worlds: Couple Satisfaction, Parenting Style, and Mothers' and Fathers' Speech to Young Children.

ERIC Educational Resources Information Center

Pratt, Michael W.; And Others

1992-01-01

Investigated relations between certain family context variables and the conversational behavior of 36 parents who were playing with their 3 year olds. Transcripts were coded for types of conversational functions and structure of parent speech. Marital satisfaction was associated with aspects of parent speech. (LB)

A component-centered meta-analysis of family-based prevention programs for adolescent substance use.

PubMed

Van Ryzin, Mark J; Roseth, Cary J; Fosco, Gregory M; Lee, You-Kyung; Chen, I-Chien

2016-04-01

Although research has documented the positive effects of family-based prevention programs, the field lacks specific information regarding why these programs are effective. The current study summarized the effects of family-based programs on adolescent substance use using a component-based approach to meta-analysis in which we decomposed programs into a set of key topics or components that were specifically addressed by program curricula (e.g., parental monitoring/behavior management,problem solving, positive family relations, etc.). Components were coded according to the amount of time spent on program services that targeted youth, parents, and the whole family; we also coded effect sizes across studies for each substance-related outcome. Given the nested nature of the data, we used hierarchical linear modeling to link program components (Level 2) with effect sizes (Level 1). The overall effect size across programs was .31, which did not differ by type of substance. Youth-focused components designed to encourage more positive family relationships and a positive orientation toward the future emerged as key factors predicting larger than average effect sizes. Our results suggest that, within the universe of family-based prevention, where components such as parental monitoring/behavior management are almost universal, adding or expanding certain youth-focused components may be able to enhance program efficacy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis, antimicrobial activity and gene structure of a novel member of the dermaseptin B family.

PubMed

Fleury, Y; Vouille, V; Beven, L; Amiche, M; Wróblewski, H; Delfour, A; Nicolas, P

1998-03-09

Dermaseptins are a family of cationic (Lys-rich) antimicrobial peptides that are abundant in the skin secretions of the arboreal frogs Phyllomedusa bicolor and P. sauvagii. In vitro, these peptides are microbicidal against a wide variety of microorganisms including Gram-positive and Gram-negative bacteria, yeasts, protozoa and fungi. To date, 6 dermaseptin B mature peptides, 24-34 residues long, 2 dermaseptin B cDNAs and 2 gene sequences have been identified in P. bicolor. To assess dermaseptin related genes further, we screened a P. bicolor genomic library with 32P-labeled cDNAs coding either for prepro-dermaseptins B1 or B2 (adenoregulin). A gene sequence was identified that coded a novel dermaseptin B, termed Drg3, which exhibits 23-42% amino acids identities with other members of the family. Analysis of the cDNAs coding precursors for several opioid and antimicrobial peptides originating from the skin of various amphibian species revealed that the 25-residue preproregion of these preproforms are all encoded by conserved nucleotides encompassed by the first coding exon of the Drg3 gene. Synthetic dermaseptin Drg3 exhibited a bactericidal activity towards several species of mollicutes (wall-less eubacteria), firmicutes (Gram-positive eubacteria), and gracilicutes (Gram-negative eubacteria), with minimal inhibitory concentrations (MICs) ranging from 6.25 to 100 microM. Experiments performed on Acholeplasma laidlawii cells revealed that this peptide is membranotropic and that if efficiently depolarizes the plasma membrane.

Code Krishna: an innovative practice respecting death, dying and beyond.

PubMed

Vaishnav, Bhalendu; Nimbalkar, Somashekhar; Desai, Sandeep; Vaishnav, Smruti

2017-01-01

In moments of grief, human beings seek solace and attempt to discover the meaning of life and death by reaching out to wider and deeper dimensions of existence that stem from their religious, cultural and spiritual beliefs. Conventional patient care fails to consider this vital aspect of our lives. Many hold the view that life and its experiences do not end with death; the body is but a sheath which holds the soul that inhabits it. The use of a protocol-based practice to create a solemn atmosphere around the departed individual can bridge the gap between the materialistic and non-materialistic perceptions of the dimensions of care. The innovative practice, "Code Krishna", is aimed at institutionalising a practice which sensitises and empowers the treating team to address the grief of the relatives of deceased patients, and respect the departed in consonance with the family's cultural, religious and spiritual beliefs. The practice entails the creation of a solemn atmosphere amidst the action-packed environment of the critical care unit at the time of the patient's death, offering of collective prayer and floral tributes, and observation of silence both by the healthcare team and family members. Code Krishna attempts to blend current care practices with spirituality, ensuring that the treating team is the first to commiserate with the grieving family, with warmth and openness. In this piece, we briefly report our first-hand experiences of practising Code Krishna in our hospital [Shree Krishna Hospital, Karamsad, Central Gujarat].

Adapting the coping in deliberation (CODE) framework: a multi-method approach in the context of familial ovarian cancer risk management.

PubMed

Witt, Jana; Elwyn, Glyn; Wood, Fiona; Rogers, Mark T; Menon, Usha; Brain, Kate

2014-11-01

To test whether the coping in deliberation (CODE) framework can be adapted to a specific preference-sensitive medical decision: risk-reducing bilateral salpingo-oophorectomy (RRSO) in women at increased risk of ovarian cancer. We performed a systematic literature search to identify issues important to women during deliberations about RRSO. Three focus groups with patients (most were pre-menopausal and untested for genetic mutations) and 11 interviews with health professionals were conducted to determine which issues mattered in the UK context. Data were used to adapt the generic CODE framework. The literature search yielded 49 relevant studies, which highlighted various issues and coping options important during deliberations, including mutation status, risks of surgery, family obligations, physician recommendation, peer support and reliable information sources. Consultations with UK stakeholders confirmed most of these factors as pertinent influences on deliberations. Questions in the generic framework were adapted to reflect the issues and coping options identified. The generic CODE framework was readily adapted to a specific preference-sensitive medical decision, showing that deliberations and coping are linked during deliberations about RRSO. Adapted versions of the CODE framework may be used to develop tailored decision support methods and materials in order to improve patient-centred care. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Relation between premorbid personality and patterns of emotion expression in mid- to late-stage dementia.

PubMed

Magai, C; Cohen, C I; Culver, C; Gomberg, D; Malatesta, C

1997-11-01

Twenty-seven nursing home patients with mid- to late-stage dementia participated in a study of the relation between preillness personality, as indexed by attachment and emotion regulation style, and current emotional behavior. Preillness measures were completed by family members and current assessments of emotion were supplied by nursing home aides and family members; in addition, emotion was coded during a family visit using an objective coding system for facial emotion expressions. Attachment style was found to be related to the expression of positive affect, with securely attached individuals displaying more positive affect than avoidantly attached individuals. In addition, high ratings on premorbid hostility were associated with higher rates of negative affect and lower rates of positive affect. These findings indicate that premorbid aspects of personality show continuity over time, even in mid- to late-stage dementia.

Billing by residents and attending physicians in family medicine: the effects of the provider, patient, and visit factors.

PubMed

Al Achkar, Morhaf; Kengeri-Srikantiah, Seema; Yamane, Biniyam M; Villasmil, Jomil; Busha, Michael E; Gebke, Kevin B

2018-06-13

Medical billing and coding are critical components of residency programs since they determine the revenues and vitality of residencies. It has been suggested that residents are less likely to bill higher evaluation and management (E/M) codes compared with attending physicians. The purpose of this study is to assess the variation in billing patterns between residents and attending physicians, considering provider, patient, and visit characteristics. A retrospective cohort study of all established outpatient visits at a family medicine residency clinic over a 5-year period was performed. We employed the logistic regression methodology to identify residents' and attending physicians' variations in coding E/M service levels. We also employed Poisson regression to test the sensitivity of our result. Between January 5, 2009 and September 25, 2015, 98,601 visits to 116 residents and 18 attending physicians were reviewed. After adjusting for provider, patient, and visit characteristics, residents billed higher E/M codes less often compared with attending physicians for comparable visits. In comparison with attending physicians, the odds ratios for billing higher E/M codes were 0.58 (p = 0.01), 0.56 (p = 0.01), and 0.63 (p = 0.01) for the third, second, and first years of postgraduate training, respectively. In addition to the main factors of patient age, medical conditions, and number of addressed problems, the gender of the provider was also implicated in the billing variations. Residents are less likely to bill higher E/M codes than attending physicians are for similar visits. While these variations are known to contribute to lost revenues, further studies are required to explore their effect on patient care in relation to attendings' direct involvement in higher E/M-coded versus their indirect involvement in lower E/M-coded visits.

TOUGH+ v1.5 Core Code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moridis, George J.

TOUGH+ v1.5 is a numerical code for the simulation of multi-phase, multi-component flow and transport of mass and heat through porous and fractured media, and represents the third update of the code since its first release [Moridis et al., 2008]. TOUGH+ is a successor to the TOUGH2 [Pruess et al., 1991; 2012] family of codes for multi-component, multiphase fluid and heat flow developed at the Lawrence Berkeley National Laboratory. It is written in standard FORTRAN 95/2003, and can be run on any computational platform (workstations, PC, Macintosh). TOUGH+ v1.5 employs dynamic memory allocation, thus minimizing storage requirements. It has amore » completely modular structure, follows the tenets of Object-Oriented Programming (OOP), and involves the advanced features of FORTRAN 95/2003, i.e., modules, derived data types, the use of pointers, lists and trees, data encapsulation, defined operators and assignments, operator extension and overloading, use of generic procedures, and maximum use of the powerful intrinsic vector and matrix processing operations. TOUGH+ v1.5 is the core code for its family of applications, i.e., the part of the code that is common to all its applications. It provides a description of the underlying physics and thermodynamics of non-isothermal flow, of the mathematical and numerical approaches, as well as a detailed explanation of the general (common to all applications) input requirements, options, capabilities and output specifications. The core code cannot run by itself: it needs to be coupled with the code for the specific TOUGH+ application option that describes a particular type of problem. The additional input requirements specific to a particular TOUGH+ application options and related illustrative examples can be found in the corresponding User's Manual.« less

Civil Code, 11 December 1987.

PubMed

1988-01-01

Article 162 of this Mexican Code provides, among other things, that "Every person has the right freely, responsibly, and in an informed fashion to determine the number and spacing of his or her children." When a marriage is involved, this right is to be observed by the spouses "in agreement with each other." The civil codes of the following states contain the same provisions: 1) Baja California (Art. 159 of the Civil Code of 28 April 1972 as revised in Decree No. 167 of 31 January 1974); 2) Morelos (Art. 255 of the Civil Code of 26 September 1949 as revised in Decree No. 135 of 29 December 1981); 3) Queretaro (Art. 162 of the Civil Code of 29 December 1950 as revised in the Act of 9 January 1981); 4) San Luis Potosi (Art. 147 of the Civil Code of 24 March 1946 as revised in 13 June 1978); Sinaloa (Art. 162 of the Civil Code of 18 June 1940 as revised in Decree No. 28 of 14 October 1975); 5) Tamaulipas (Art. 146 of the Civil Code of 21 November 1960 as revised in Decree No. 20 of 30 April 1975); 6) Veracruz-Llave (Art. 98 of the Civil Code of 1 September 1932 as revised in the Act of 30 December 1975); and 7) Zacatecas (Art. 253 of the Civil Code of 9 February 1965 as revised in Decree No. 104 of 13 August 1975). The Civil Codes of Puebla and Tlaxcala provide for this right only in the context of marriage with the spouses in agreement. See Art. 317 of the Civil Code of Puebla of 15 April 1985 and Article 52 of the Civil Code of Tlaxcala of 31 August 1976 as revised in Decree No. 23 of 2 April 1984. The Family Code of Hidalgo requires as a formality of marriage a certification that the spouses are aware of methods of controlling fertility, responsible parenthood, and family planning. In addition, Article 22 the Civil Code of the Federal District provides that the legal capacity of natural persons is acquired at birth and lost at death; however, from the moment of conception the individual comes under the protection of the law, which is valid with respect to the individual as far as the effects of this law provides as if the individual were already born. full text

Ethics and the Early Childhood Teacher Educator: A Proposed Addendum to the NAEYC Code of Ethical Conduct.

ERIC Educational Resources Information Center

Freeman, Nancy; Feeney, Stephanie; Moravcik, Eva

2003-01-01

Proposes an addendum to the National Association for the Education of Young Children's Code of Ethical Conduct concerning the unique ethical challenges facing teacher educators. Presents a conception of professional responsibility in six areas: children and families, adult students, programs hosting practicum students and programs' staffs and…

A transactional approach to preventing early childhood neglect: The Family Check-Up as a public health strategy.

PubMed

Dishion, Thomas J; Mun, Chung Jung; Drake, Emily C; Tein, Jenn-Yun; Shaw, Daniel S; Wilson, Melvin

2015-11-01

This study examined the hypothesis that a brief, strengths-based home visiting strategy can promote positive engagement between caregiver and child and thereby reduce various forms of early childhood neglect. A total of 731 low-income families receiving services through the Women, Infants, and Children nutritional supplement program were randomized to the Women, Infants, and Children as usual or the Family Check-Up intervention. Assessments and intervention services were delivered in the home environment at ages 2, 3, 4, and 5. During the assessments, staff videotaped caregiver-child interactions and rated various features of the home environment, including the physical appropriateness of the home setting for children. Trained observers later coded the videotapes, unaware of the family's intervention condition. Specific caregiver-child interaction patterns were coded and macroratings were made of the caregiver's affection, monitoring, and involvement with the child. An intention to treat design revealed that randomization to the Family Check-Up increased duration of positive engagement between caregivers and children by age 3, which in turn was prognostic of less neglect of the child at age 4, controlling for family adversity. It was also found that family adversity moderated the impact of the intervention, such that the families with the most adverse circumstances were highly responsive to the intervention. Families with the highest levels of adversity exhibited the strongest mediation between positive engagement and reduction of neglect. Findings are discussed with respect to developmental theory and their potential implications for a public health approach to the prevention of early childhood maltreatment.

Explanatory Parent-Child Conversation Predominates at an Evolution Exhibit

ERIC Educational Resources Information Center

Tare, Medha; French, Jason; Frazier, Brandy N.; Diamond, Judy; Evans, E. Margaret

2011-01-01

To investigate how parents support children's learning at an exhibit on evolution, the conversations of 12 families were recorded, transcribed, and coded (6,263 utterances). Children (mean age 9.6 years) and parents visited Explore Evolution, which conveyed current research about the evolution of seven organisms. Families were engaged with the…

Perpetuating Core Values in Family and Consumer Sciences

ERIC Educational Resources Information Center

Richards, Virginia

2005-01-01

The American Association of Family and Consumer Sciences (AAFCS) Code of Ethics guides members on ethical practice in specific areas, however, becoming ethical does not happen at the moment a major is declared or on graduation day. Ethical values are formed in childhood by the examples provided by parents, teachers, and other significant adults.…

78 FR 64483 - Meeting of the Department of Defense Military Family Readiness Council

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-29

... DEPARTMENT OF DEFENSE Office of the Secretary Meeting of the Department of Defense Military Family Readiness Council AGENCY: Department of Defense. ACTION: Notice. SUMMARY: The Department of Defense is... Register Liaison Officer, Department of Defense. [FR Doc. 2013-25512 Filed 10-28-13; 8:45 am] BILLING CODE...

Emotional Communication in Families of Conduct Problem Children with High versus Low Callous-Unemotional Traits

ERIC Educational Resources Information Center

Pasalich, Dave S.; Dadds, Mark R.; Vincent, Lucy C.; Cooper, Francesca A.; Hawes, David J.; Brennan, John

2012-01-01

This study examined relationships between parent-child emotional communication and callous-unemotional (CU) traits and conduct problems. References to negative and positive emotions made by clinic-referred boys (3-9 years) and their parents were coded from direct observations of family interactions involving the discussion of shared emotional…

Consumer and Family Economics. Second Edition.

ERIC Educational Resources Information Center

Texas Tech Univ., Lubbock. Home Economics Curriculum Center.

This consumer and family economics curriculum guide was developed for use in home economics education in Texas. At the beginning is a list of the competencies and the subcompetencies that are the essential elements and the subelements prescribed in the Texas Administrative Codes for Vocational Home Economics. The conceptual outline as shown in the…

The Role of the Primary Caregiving Father.

ERIC Educational Resources Information Center

Frank, Robert A.

This dissertation examined primary caregiving father families and how they construct their roles in contrast to primary caregiving mother families. A Self-report survey instrument was constructed. and administered to a sample of 93 married couples in the United States with children under the age of 6. Surveys were coded by couple, analyzed, and…

Processes of Sibling Influence in Adolescence: Individual and Family Correlates

ERIC Educational Resources Information Center

Whiteman, Shawn D.; Christiansen, Abigail

2008-01-01

This study examined the nature and correlates of adolescents' perceptions of sibling influence. Participants included 2 siblings (firstborn age M = 17.34; second-born age M = 14.76 years) from 191 maritally intact families. Adolescents' perceptions of sibling influence were measured via coded responses to open-ended questions about whether their…

Family planning and contraceptive decision-making by economically disadvantaged, African-American women

PubMed Central

Hodgson, Eric J.; Collier, Charlene; Hayes, Laura; Curry, Leslie; Fraenkel, Liana

2013-01-01

Background Significant racial disparities exist in the US unplanned pregnancy rate. We conducted a qualitative study using the theory of planned behavior as a framework to describe how low-income, African-American women approach family planning. Study Design Structured focus groups were held with adult, low-income, non-pregnant, African-American women in Connecticut. Data were collected using a standardized discussion guide, and audio-taped and transcribed. Four, independent researchers coded the transcripts using the constant comparative method. Codes were organized into over-arching themes. Results Contraceptive knowledge was limited with formal education often occurring after sexual debut. Attitudes about contraception were overtly negative with method effectiveness being judged by the experience of side effects. Family and friends strongly influence contraceptive decisions while male partners are primarily seen as a barrier. Contraceptive pills are perceived as readily accessible although compliance is considered a barrier. Conclusions Contraception education should occur before sexual debut, should involve trusted family and community members, and should positively frame issues in terms of achieving life goals. PMID:23177266

On the Origin of Protein Superfamilies and Superfolds

NASA Astrophysics Data System (ADS)

Magner, Abram; Szpankowski, Wojciech; Kihara, Daisuke

2015-02-01

Distributions of protein families and folds in genomes are highly skewed, having a small number of prevalent superfamiles/superfolds and a large number of families/folds of a small size. Why are the distributions of protein families and folds skewed? Why are there only a limited number of protein families? Here, we employ an information theoretic approach to investigate the protein sequence-structure relationship that leads to the skewed distributions. We consider that protein sequences and folds constitute an information theoretic channel and computed the most efficient distribution of sequences that code all protein folds. The identified distributions of sequences and folds are found to follow a power law, consistent with those observed for proteins in nature. Importantly, the skewed distributions of sequences and folds are suggested to have different origins: the skewed distribution of sequences is due to evolutionary pressure to achieve efficient coding of necessary folds, whereas that of folds is based on the thermodynamic stability of folds. The current study provides a new information theoretic framework for proteins that could be widely applied for understanding protein sequences, structures, functions, and interactions.

PubMed Central

Leduc, Y.; Cauchon, M.; Emond, J. G.; Ouellet, J.

1995-01-01

OBJECTIVE: To develop and implement a computerized version of the International Classification of Primary Care. To create a data bank and to conduct a descriptive study of our clinic's clientele. DESIGN: Testing a software program and creating a data bank. SETTING: Family Medicine Unit at Enfant-Jésus Hospital, Quebec City. PARTICIPANTS: All Family Medicine Unit doctors and patients seen between July 1, 1990, and June 30, 1993. MAIN OUTCOME MEASURE: Description of our clientele's health problems using the ICPC. RESULTS: During the study, 48,415 diagnostic codes for 33,033 visits were entered into the bank. For close to 50% of these visits, two or more health problems were coded. There was good correlation between the description of our clientele and descriptions in other studies in the literature. CONCLUSION: This article describes the development of a data bank in a family medicine unit using a software program based on the ICPC. Our 3-year experiment demonstrated that the method works well in family physicians' daily practice. A descriptive study of our clientele is presented, as well as a few examples of the many applications of such a data bank. PMID:7580382

Third Party Interaction in the Medical Context: Code-switching and Control

PubMed Central

Vickers, Caroline H.; Goble, Ryan; Deckert, Sharon K.

2015-01-01

The purpose of this paper is to examine the micro-interactional co-construction of power within Spanish language concordant medical consultations in California involving a third party family member. Findings indicate the third party instigates code-switching to English on the part of medical providers, a language that the patient does not understand, rendering the patient a non-participant in the medical consultation. In these consultations involving a third party family member, monolingual Spanish-speaking patients are stripped of control in ways that are similar to other powerless groups in medical consultations. Implications include the need to further examine how micro-level interactions reproduce societal ideologies and shape policy on the ground. PMID:27667896

libvdwxc: a library for exchange-correlation functionals in the vdW-DF family

NASA Astrophysics Data System (ADS)

Hjorth Larsen, Ask; Kuisma, Mikael; Löfgren, Joakim; Pouillon, Yann; Erhart, Paul; Hyldgaard, Per

2017-09-01

We present libvdwxc, a general library for evaluating the energy and potential for the family of vdW-DF exchange-correlation functionals. libvdwxc is written in C and provides an efficient implementation of the vdW-DF method and can be interfaced with various general-purpose DFT codes. Currently, the Gpaw and Octopus codes implement interfaces to libvdwxc. The present implementation emphasizes scalability and parallel performance, and thereby enables ab initio calculations of nanometer-scale complexes. The numerical accuracy is benchmarked on the S22 test set whereas parallel performance is benchmarked on ligand-protected gold nanoparticles ({{Au}}144{({{SC}}11{{NH}}25)}60) up to 9696 atoms.

Reconsideration of systematic relationships within the order Euplotida (Protista, Ciliophora) using new sequences of the gene coding for small-subunit rRNA and testing the use of combined data sets to construct phylogenies of the Diophrys-complex.

PubMed

Yi, Zhenzhen; Song, Weibo; Clamp, John C; Chen, Zigui; Gao, Shan; Zhang, Qianqian

2009-03-01

Comprehensive molecular analyses of phylogenetic relationships within euplotid ciliates are relatively rare, and the relationships among some families remain questionable. We performed phylogenetic analyses of the order Euplotida based on new sequences of the gene coding for small-subunit RNA (SSrRNA) from a variety of taxa across the entire order as well as sequences from some of these taxa of other genes (ITS1-5.8S-ITS2 region and histone H4) that have not been included in previous analyses. Phylogenetic trees based on SSrRNA gene sequences constructed with four different methods had a consistent branching pattern that included the following features: (1) the "typical" euplotids comprised a paraphyletic assemblage composed of two divergent clades (family Uronychiidae and families Euplotidae-Certesiidae-Aspidiscidae-Gastrocirrhidae), (2) in the family Uronychiidae, the genera Uronychia and Paradiophrys formed a clearly outlined, well-supported clade that seemed to be rather divergent from Diophrys and Diophryopsis, suggesting that the Diophrys-complex may have had a longer and more separate evolutionary history than previously supposed, (3) inclusion of 12 new SSrRNA sequences in analyses of Euplotidae revealed two new clades of species within the family and cast additional doubt on the present classification of genera within the family, and (4) the intraspecific divergence among five species of Aspidisca was far greater than those of closely related genera. The ITS1-5.8S-ITS2 coding regions and partial histone H4 genes of six morphospecies in the Diophrys-complex were sequenced along with their SSrRNA genes and used to compare phylogenies constructed from single data sets to those constructed from combined sets. Results indicated that combined analyses could be used to construct more reliable, less ambiguous phylogenies of complex groups like the order Euplotida, because they provide a greater amount and diversity of information.

Regulation of cellulase expression, sporulation, and morphogenesis by velvet family proteins in Trichoderma reesei.

PubMed

Liu, Kuimei; Dong, Yanmei; Wang, Fangzhong; Jiang, Baojie; Wang, Mingyu; Fang, Xu

2016-01-01

Homologs of the velvet protein family are encoded by the ve1, vel2, and vel3 genes in Trichoderma reesei. To test their regulatory functions, the velvet protein-coding genes were disrupted, generating Δve1, Δvel2, and Δvel3 strains. The phenotypic features of these strains were examined to identify their functions in morphogenesis, sporulation, and cellulase expression. The three velvet-deficient strains produced more hyphal branches, indicating that velvet family proteins participate in the morphogenesis in T. reesei. Deletion of ve1 and vel3 did not affect biomass accumulation, while deletion of vel2 led to a significantly hampered growth when cellulose was used as the sole carbon source in the medium. The deletion of either ve1 or vel2 led to the sharp decrease of sporulation as well as a global downregulation of cellulase-coding genes. In contrast, although the expression of cellulase-coding genes of the ∆vel3 strain was downregulated in the dark, their expression in light condition was unaffected. Sporulation was hampered in the ∆vel3 strain. These results suggest that Ve1 and Vel2 play major roles, whereas Vel3 plays a minor role in sporulation, morphogenesis, and cellulase expression.

Distillation with Sublogarithmic Overhead

NASA Astrophysics Data System (ADS)

Hastings, Matthew B.; Haah, Jeongwan

2018-02-01

It has been conjectured that, for any distillation protocol for magic states for the T gate, the number of noisy input magic states required per output magic state at output error rate ɛ is Ω [log (1 /ɛ )] . We show that this conjecture is false. We find a family of quantum error correcting codes of parameters ⟦ ∑ i =w +1 m (m i ),∑ i =0 w (m i ),∑ i =w +1 r +1 (r +1 i )⟧ for any integers m >2 r , r >w ≥0 , by puncturing quantum Reed-Muller codes. When m >ν r , our code admits a transversal logical gate at the ν th level of Clifford hierarchy. In a distillation protocol for magic states at the level ν =3 (T gate), the ratio of input to output magic states is O (logγ(1 /ɛ )) , where γ =log (n /k )/log (d )<0.678 for some m , r , w . The smallest code in our family for which γ <1 is on ≈258 qubits.

Cultural Socialization in Families with Adopted Korean Adolescents: A Mixed-Method, Multi-Informant Study

PubMed Central

Kim, Oh Myo; Reichwald, Reed; Lee, Richard M.

2012-01-01

Transracial, transnational families understand and transmit cultural socialization messages in ways that differ from same-race families. This study explored the ways in which transracial, transnational adoptive families discuss race and ethnicity and how these family discussions compared to self-reports from adoptive parents and adolescents regarding the level of parental engagement in cultural socialization. Of the thirty families with at least one adolescent-aged child (60% female, average age 17.8 years) who was adopted from South Korea, nine families acknowledged racial and ethnic differences, six families rejected racial and ethnic differences, and fifteen families held a discrepancy of views. Parents also reported significantly greater engagement in cultural socialization than adolescents’ reports of parental engagement. However, only adolescent self-reports of parental engagement in cultural socialization matched the qualitative coding of family conversations. PMID:24235782

Family Functioning Differences Across the Deployment Cycle in British Army Families: The Perceptions of Wives and Children.

PubMed

Pye, Rachel E; Simpson, Leanne K

2017-09-01

Military deployment can have an adverse effect on a soldier's family, though little research has looked at these effects in a British sample. We investigated wives' of U.K.-serving soldiers perceptions of marital and family functioning, across three stages of the deployment cycle: currently deployed, postdeployment and predeployed, plus a nonmilitary comparison group. Uniquely, young (aged 3.5-11 years) children's perceptions of their family were also investigated, using the parent-child alliance (PCA) coding scheme of drawings of the family. Two hundred and twenty British military families of regular service personnel from the British Army's Royal Armoured Corps, were sent survey packs distributed with a monthly welfare office newsletter. Wives were asked to complete a series of self-report items, and the youngest child in the family between the ages of 3.5 and 11 years was asked to draw a picture of their family. Complete data were available for 78 military families, and an additional 34 nonmilitary families were recruited via opportunity sampling. Results indicated wives of currently deployed and recently returned personnel were less satisfied with their family and its communication, and children's pictures indicated higher levels of dysfunctional parent-child alliance, whereas predeployed families responded similarly to nonmilitary families. Marital satisfaction was similar across all groups except predeployed families who were significantly more satisfied. Nonmilitary and predeployed families showed balanced family functioning, and currently and recently deployed families demonstrated poor family functioning. In comparison to nonmilitary families, predeployed families showed a large "spike" in the rigidity subscale of the Family Adaptability and Cohesion Evaluation Scale IV. Wives' perceptions of family functioning, but not marital satisfaction, differed between the deployment groups. The results from the coded children's drawings correlated with the self-report measures from the wife/mother, indicating that children's drawings could be a useful approach when working with younger children in this area. It is tentatively suggested that the differences across deployment stage on family functioning could be mediated not only by communication difficulties between deployed personnel and their families, but also by its effect on the children in the family. Larger-scale longitudinal research is needed to investigate this further. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

How Sensory Experiences of Children With and Without Autism Affect Family Occupations

PubMed Central

Bagby, Molly Shields; Dickie, Virginia A.; Baranek, Grace T.

2012-01-01

We used a grounded theory approach to data analysis to discover what effect, if any, children's sensory experiences have on family occupations. We chose this approach because the existing literature does not provide a theory to account for the effect of children's sensory experiences on family occupations. Parents of six children who were typically developing and six children who had autism were interviewed. We analyzed the data using open, axial, and selective coding techniques. Children's sensory experiences affect family occupations in three ways: (1) what a family chooses to do or not do; (2) how the family prepares; and (3) the extent to which experiences, meaning, and feelings are shared. PMID:22389942

Visits to Registered Nurses

PubMed Central

Parker, Emese C.; Kong, Kevin; Watts, Leslie A.; Schwarz, Eleanor B.; Darney, Philip D.; Thiel de Bocanegra, Heike

2017-01-01

Background In 2013, California passed Assembly Bill (A.B.) 2348, approving registered nurses (RNs) to dispense patient self-administered hormonal contraceptives and administer injections of hormonal contraceptives. The Family Planning, Access, Care and Treatment (Family PACT) program, which came into effect in 1997 to expand low-income, uninsured California resident access to contraceptives at no cost, is one program in which qualified RNs can dispense and administer contraceptives. Aims The aims of this study were to (a) describe utilization of RN visits within California's Family PACT program and (b) evaluate the impact of RN visits on client birth control acquisition during the first 18 months after implementation of A.B. 2348 (January 1, 2013 to June 30, 2014). Methods A descriptive observational design using administrative databases was used. Family PACT claims were retrieved for RN visits and contraception. Paid claims for contraceptive dispensing and/or administration visits by physicians, nurse practitioners, certified nurse midwives, and physician assistants were compared before and after the implementation of A.B. 2348 at practice sites where RN visits were and were not utilized. Contraceptive methods and administration procedures were identified using Healthcare Common Procedure Coding System codes, National Drug Codes, and Common Procedural Terminology codes. Claims data for healthcare facilities were abstracted by site location based on a unique combination of National Provider Identifier (NPI), NPI Owner, and NPI location number. Results RN visits were found mainly in Northern California and the Central Valley (73%). Sixty-eight percent of RN visits resulted in same-day dispensing and/or administration of hormonal (and/or barrier) methods. Since benefit implementation, RN visits resulted in a 10% increase in access to birth control dispensing and/or administration visits. RN visits were also associated with future birth control acquisition and other healthcare utilization within the subsequent 30 days. Discussion RN visits, though underutilized across the state, have resulted in increased access to contraception in some communities, an effect that may continue to grow with time and can serve as a model for other states. PMID:28604507

Visits to Registered Nurses: An Opportunity to Increase Contraceptive Access in California.

PubMed

Parker, Emese C; Kong, Kevin; Watts, Leslie A; Schwarz, Eleanor B; Darney, Philip D; Thiel de Bocanegra, Heike

In 2013, California passed Assembly Bill (A.B.) 2348, approving registered nurses (RNs) to dispense patient self-administered hormonal contraceptives and administer injections of hormonal contraceptives. The Family Planning, Access, Care and Treatment (Family PACT) program, which came into effect in 1997 to expand low-income, uninsured California resident access to contraceptives at no cost, is one program in which qualified RNs can dispense and administer contraceptives. The aims of this study were to (a) describe utilization of RN visits within California's Family PACT program and (b) evaluate the impact of RN visits on client birth control acquisition during the first 18 months after implementation of A.B. 2348 (January 1, 2013 to June 30, 2014). A descriptive observational design using administrative databases was used. Family PACT claims were retrieved for RN visits and contraception. Paid claims for contraceptive dispensing and/or administration visits by physicians, nurse practitioners, certified nurse midwives, and physician assistants were compared before and after the implementation of A.B. 2348 at practice sites where RN visits were and were not utilized. Contraceptive methods and administration procedures were identified using Healthcare Common Procedure Coding System codes, National Drug Codes, and Common Procedural Terminology codes. Claims data for healthcare facilities were abstracted by site location based on a unique combination of National Provider Identifier (NPI), NPI Owner, and NPI location number. RN visits were found mainly in Northern California and the Central Valley (73%). Sixty-eight percent of RN visits resulted in same-day dispensing and/or administration of hormonal (and/or barrier) methods. Since benefit implementation, RN visits resulted in a 10% increase in access to birth control dispensing and/or administration visits. RN visits were also associated with future birth control acquisition and other healthcare utilization within the subsequent 30 days. RN visits, though underutilized across the state, have resulted in increased access to contraception in some communities, an effect that may continue to grow with time and can serve as a model for other states.

A single-item global job satisfaction measure is associated with quantitative blood immune indices in white-collar employees.

PubMed

Nakata, Akinori; Irie, Masahiro; Takahashi, Masaya

2013-01-01

Although a single-item job satisfaction measure has been shown to be reliable and inclusive as multiple-item scales in relation to health, studies including immunological data are few. The purpose of this study was to evaluate the validity of single-item job and family life satisfaction based on its association with immune indices. A total of 189 white-collar employees (70% men) underwent a blood draw for the measurement of natural killer (NK), total T, and B cell counts as well as plasma immunoglobulin (Ig) G concentrations and completed single-item job and family life satisfaction measures, respectively. The response options for satisfaction measures were 'dissatisfied' (coded 1) to 'satisfied' (coded 4). Spearman's partial correlations controlling for cofactors revealed that increased job satisfaction was positively associated with NK cells (rsp=0.201, p=0.007) and IgG (rsp=0.178, p=0.018), while family life satisfaction was unrelated to immune indices. Those who reported a combination of low job/low family life satisfaction had significantly lower NK and higher B cell counts than those with a high job/high family life satisfaction. Our study suggests that the single-item summary measure of job satisfaction, but not family life satisfaction, may be a valid tool to evaluate immune status in healthy white-collar employees.

A Single-item Global Job Satisfaction Measure Is Associated with Quantitative Blood Immune Indices in White-collar Employees

PubMed Central

Nakata, Akinori; Irie, Masahiro; Takahashi, Masaya

2015-01-01

Although a single-item job satisfaction measure has been shown to be reliable and inclusive as multiple-item scales in relation to health, studies including immunological data are few. The purpose of this study was to evaluate the validity of single-item job and family life satisfaction based on its association with immune indices. A total of 189 white-collar employees (70% men) underwent a blood draw for the measurement of natural killer (NK), total T, and B cell counts as well as plasma immunoglobulin (Ig) G concentrations and completed single-item job and family life satisfaction measures, respectively. The response options for satisfaction measures were ‘dissatisfied’ (coded 1) to ‘satisfied’ (coded 4). Spearman’s partial correlations controlling for cofactors revealed that increased job satisfaction was positively associated with NK cells (rsp=0.201, p=0.007) and IgG (rsp=0.178, p=0.018), while family life satisfaction was unrelated to immune indices. Those who reported a combination of low job/low family life satisfaction had significantly lower NK and higher B cell counts than those with a high job/high family life satisfaction. Our study suggests that the single-item summary measure of job satisfaction, but not family life satisfaction, may be a valid tool to evaluate immune status in healthy white-collar employees. PMID:23196390

Defining and Predicting Pimps' Coerciveness Toward Sex Workers: Socialization Processes.

PubMed

Stalans, Loretta J; Finn, Mary A

2016-10-01

Prior research has found that pimps use both non-coercive and coercive management styles across and within market segments of the illicit sex trade. The current study is the first to examine the socialization processes underlying variation in the self-reported coerciveness of pimps. This study begins to fill a void in the almost non-existent research on pimps who are actively managing Internet-solicited sex workers, and adds to the sparse research on pimps' coerciveness. We extend Anderson's concepts of "street code" families, where respect is acquired through displaying physical violence and toughness, and "decent" families, where middle class values of avoiding unnecessary aggression and complying with the law prevail, to understand variation in the degree of coerciveness that pimps utilize toward sex workers. A purposive sample of 44 active pimps was obtained through referrals from selected pimps and through placing advertisements on Backpage, a website utilized by the illicit prostitution trade. Qualitative coding revealed a wide range of coercive control tactics such as supplying drugs, surveillance, and physical violence. Pimps who served as sex workers and those raised by parents who supported "the code of the street" reported use of a greater number of more severe coercive tactics. College-educated pimps, pimps operating business that charged fees of at least US$300, and those from "decent" families were more likely to use non-coercive management. These findings suggest that early prevention programs might address the "street code" mentality that contributes to coerciveness, and that "End Demand" policies need to recognize that many male pimps also have served as sex workers.

The Validation of Macro and Micro Observations of Parent–Child Dynamics Using the Relationship Affect Coding System in Early Childhood

PubMed Central

Mun, Chung Jung; Tein, Jenn-Yun; Kim, Hanjoe; Shaw, Daniel S.; Gardner, Frances; Wilson, Melvin N.; Peterson, Jenene

2018-01-01

This study examined the validity of micro social observations and macro ratings of parent–child interaction in early to middle childhood. Seven hundred and thirty-one families representing multiple ethnic groups were recruited and screened as at risk in the context of Women, Infant, and Children (WIC) Nutritional Supplement service settings. Families were randomly assigned to the Family Checkup (FCU) intervention or the control condition at age 2 and videotaped in structured interactions in the home at ages 2, 3, 4, and 5. Parent–child interaction videotapes were microcoded using the Relationship Affect Coding System (RACS) that captures the duration of two mutual dyadic states: positive engagement and coercion. Macro ratings of parenting skills were collected after coding the videotapes to assess parent use of positive behavior support and limit setting skills (or lack thereof). Confirmatory factor analyses revealed that the measurement model of macro ratings of limit setting and positive behavior support was not supported by the data, and thus, were excluded from further analyses. However, there was moderate stability in the families’ micro social dynamics across early childhood and it showed significant improvements as a function of random assignment to the FCU. Moreover, parent–child dynamics were predictive of chronic behavior problems as rated by parents in middle childhood, but not emotional problems. We conclude with a discussion of the validity of the RACS and on methodological advantages of micro social coding over the statistical limitations of macro rating observations. Future directions are discussed for observation research in prevention science. PMID:27620623

Barriers to Treatment of Tinea Capitis in Children Living in the Jane Finch Community of Toronto.

PubMed

Zur, Rebecca L; Shapero, Jonathan; Shapero, Harvey

2015-01-01

Tinea capitis is a common fungal infection of the scalp. If left untreated, tinea capitis infection can cause severe inflammatory reactions and the development of kerion. Tinea capitis is effectively treated with oral antifungals, but at present these are not covered under government assistance programs. To assess the potential impact of a limited use code for antifungal therapy in the treatment of childhood tinea capitis. Fourteen family physicians practicing in the Jane Finch area were surveyed on their experience treating tinea capitis in this community. Seventy-one percent of surveyed family physicians felt that cost impedes the treatment of tinea capitis in their practice, and 100% felt that a limited use code would have a positive impact on their patients. A limited use code for oral antifungal treatments of tinea capitis may provide a simple, cost-effective solution to a major problem impacting children in the Jane Finch area. © The Author(s) 2015.

Resident challenges with daily life in Chinese long-term care facilities: A qualitative pilot study.

PubMed

Song, Yuting; Scales, Kezia; Anderson, Ruth A; Wu, Bei; Corazzini, Kirsten N

As traditional family-based care in China declines, the demand for residential care increases. Knowledge of residents' experiences with long-term care (LTC) facilities is essential to improving quality of care. This pilot study aimed to describe residents' experiences in LTC facilities, particularly as it related to physical function. Semi-structured open-ended interviews were conducted in two facilities with residents stratified by three functional levels (n = 5). Directed content analysis was guided by the Adaptive Leadership Framework. A two-cycle coding approach was used with a first-cycle descriptive coding and second-cycle dramaturgical coding. Interviews provided examples of challenges faced by residents in meeting their daily care needs. Five themes emerged: staff care, care from family members, physical environment, other residents in the facility, and personal strategies. Findings demonstrate the significance of organizational context for care quality and reveal foci for future research. Copyright © 2017 Elsevier Inc. All rights reserved.

Emotion Regulation Strategies in Preschoolers with Autism: Associations with Parent Quality of Life and Family Functioning

ERIC Educational Resources Information Center

Nuske, Heather Joy; Hedley, Darren; Tseng, Chen Hsiang; Begeer, Sander; Dissanayake, Cheryl

2018-01-01

Children with autism experience challenges with emotion regulation. It is unclear how children's management of their emotions is associated with their family's quality of life. Forty-three preschoolers with autism and 28 typically developing preschoolers were coded on emotion regulation strategies used during low-level stress tasks. Parents…

How Effective Are Family Literacy Programs? Results of a Meta-Analysis

ERIC Educational Resources Information Center

van Steensel, Roel; McElvany, Nele; Kurvers, Jeanne; Herppich, Stephanie

2011-01-01

This meta-analysis examines the effects of family literacy programs on children's literacy development. It analyzes the results of 30 recent effect studies (1990-2010), covering 47 samples, and distinguishes between effects in two domains: comprehension-related skills and code-related skills. A small but significant mean effect emerged (d = 0.18).…

Inside the Black Box: An Exploration of Service Delivery in a Family Reunification Program.

ERIC Educational Resources Information Center

Staff, Ilene; Fein, Edith

1994-01-01

Describes a three-month study of a family reunification program for abused and neglected children that explored the process and outcomes of service delivery. The coding scheme measured both the time used in and purposes of activities of the service workers. Discusses the implications of this method for practice, planning, and research. (TM)

A Novel Family in Medicago truncatula Consisting of More Than 300 Nodule-Specific Genes Coding for Small, Secreted Polypeptides with Conserved Cysteine Motifs1[w

PubMed Central

Mergaert, Peter; Nikovics, Krisztina; Kelemen, Zsolt; Maunoury, Nicolas; Vaubert, Danièle; Kondorosi, Adam; Kondorosi, Eva

2003-01-01

Transcriptome analysis of Medicago truncatula nodules has led to the discovery of a gene family named NCR (nodule-specific cysteine rich) with more than 300 members. The encoded polypeptides were short (60–90 amino acids), carried a conserved signal peptide, and, except for a conserved cysteine motif, displayed otherwise extensive sequence divergence. Family members were found in pea (Pisum sativum), broad bean (Vicia faba), white clover (Trifolium repens), and Galega orientalis but not in other plants, including other legumes, suggesting that the family might be specific for galegoid legumes forming indeterminate nodules. Gene expression of all family members was restricted to nodules except for two, also expressed in mycorrhizal roots. NCR genes exhibited distinct temporal and spatial expression patterns in nodules and, thus, were coupled to different stages of development. The signal peptide targeted the polypeptides in the secretory pathway, as shown by green fluorescent protein fusions expressed in onion (Allium cepa) epidermal cells. Coregulation of certain NCR genes with genes coding for a potentially secreted calmodulin-like protein and for a signal peptide peptidase suggests a concerted action in nodule development. Potential functions of the NCR polypeptides in cell-to-cell signaling and creation of a defense system are discussed. PMID:12746522

Exploring the communication of oncologists, patients and family members in cancer consultations: development and application of a coding system capturing family-relevant behaviours (KINcode).

PubMed

Laidsaar-Powell, Rebekah; Butow, Phyllis; Bu, Stella; Dear, Rachel; Fisher, Alana; Coll, Joseph; Juraskova, Ilona

2016-07-01

Family members (FMs) regularly attend oncology consultations. However, limited studies have assessed actual behaviours of oncologists, patients and FMs - particularly during decision-making. The current study aimed the following: (i) to rigorously develop a family (kin) interaction coding system (KINcode) capturing communication and decision-making behaviours of FMs and family-relevant behaviours of oncologists and patients and (ii) to apply KINcode to initial oncology consultations. The 80-item KINcode system was developed and applied to 72 transcripts of audiotaped medical/radiation oncology consultations including an FM, collected as part of two previous studies. The role of the FM varied considerably within the one encounter, with 33% of FMs assuming three or more roles across the four consultation stages. Whilst most FMs asked treatment decision questions (71%), a minority engaged in other behaviours such as prompting patient questions (4%) or providing information relevant to the decision to the oncologist (18%). Although oncologists rarely initiated interaction with FMs such as in rapport building (18%) or asking FMs questions (25%), they were typically fully responsive to FM questions (90%). Many patients asked their FM a question (42%), but few elicited the FM's decision preferences (4%). This study provides novel insights into the complex nature of family involvement. The findings highlight potentially positive FM-focused consultation behaviours such as oncologist responsiveness to family questions and potential areas for improvement such as rapport building, invitation of questions and validation of the family's role. Family-specific communication skills training should be considered in medical student and professional education settings. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

A Video Recall Study of In-session Changes in Sentiment Override.

PubMed

Johnson, Lee N; Tambling, Rachel B; Anderson, Shayne R

2015-09-01

This study examines in-session changes in sentiment override over the first three sessions of couple therapy. Couples viewed a video recording of therapy sessions immediately after each of the first three sessions and continuously rated their level of sentiment override. Ninety-eight changes were randomly chosen for analysis. Three talk turns prior to each change was coded using the Family Relational Communication Control Coding System. Results show that changes in sentiment override occur frequently. Repeated incidents of communication control were related to negative change in sentiment override for females. Repeated incidents of being left out of the conversation were related to negative changes in sentiment override for females and positive changes for males. © 2014 Family Process Institute.

Changes to taxonomy and the International Code of Virus Classification and Nomenclature ratified by the International Committee on Taxonomy of Viruses (2018).

PubMed

King, Andrew M Q; Lefkowitz, Elliot J; Mushegian, Arcady R; Adams, Michael J; Dutilh, Bas E; Gorbalenya, Alexander E; Harrach, Balázs; Harrison, Robert L; Junglen, Sandra; Knowles, Nick J; Kropinski, Andrew M; Krupovic, Mart; Kuhn, Jens H; Nibert, Max L; Rubino, Luisa; Sabanadzovic, Sead; Sanfaçon, Hélène; Siddell, Stuart G; Simmonds, Peter; Varsani, Arvind; Zerbini, Francisco Murilo; Davison, Andrew J

2018-05-12

This article lists the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses in February 2018. A total of 451 species, 69 genera, 11 subfamilies, 9 families and one new order were added to the taxonomy. The current totals at each taxonomic level now stand at 9 orders, 131 families, 46 subfamilies, 803 genera and 4853 species. A change was made to the International Code of Virus Classification and Nomenclature to allow the use of the names of people in taxon names under appropriate circumstances. An updated Master Species List incorporating the approved changes was released in March 2018 ( https://talk.ictvonline.org/taxonomy/ ).

First draft genome sequencing of indole acetic acid producing and plant growth promoting fungus Preussia sp. BSL10.

PubMed

Khan, Abdul Latif; Asaf, Sajjad; Khan, Abdur Rahim; Al-Harrasi, Ahmed; Al-Rawahi, Ahmed; Lee, In-Jung

2016-05-10

Preussia sp. BSL10, family Sporormiaceae, was actively producing phytohormone (indole-3-acetic acid) and extra-cellular enzymes (phosphatases and glucosidases). The fungus was also promoting the growth of arid-land tree-Boswellia sacra. Looking at such prospects of this fungus, we sequenced its draft genome for the first time. The Illumina based sequence analysis reveals an approximate genome size of 31.4Mbp for Preussia sp. BSL10. Based on ab initio gene prediction, total 32,312 coding sequences were annotated consisting of 11,967 coding genes, pseudogenes, and 221 tRNA genes. Furthermore, 321 carbohydrate-active enzymes were predicted and classified into many functional families. Copyright © 2016 Elsevier B.V. All rights reserved.

A Phylogenomic Assessment of Ancient Polyploidy and Genome Evolution across the Poales

PubMed Central

McKain, Michael R.; Tang, Haibao; McNeal, Joel R.; Ayyampalayam, Saravanaraj; Davis, Jerrold I.; dePamphilis, Claude W.; Givnish, Thomas J.; Pires, J. Chris; Stevenson, Dennis Wm.; Leebens-Mack, James H.

2016-01-01

Comparisons of flowering plant genomes reveal multiple rounds of ancient polyploidy characterized by large intragenomic syntenic blocks. Three such whole-genome duplication (WGD) events, designated as rho (ρ), sigma (σ), and tau (τ), have been identified in the genomes of cereal grasses. Precise dating of these WGD events is necessary to investigate how they have influenced diversification rates, evolutionary innovations, and genomic characteristics such as the GC profile of protein-coding sequences. The timing of these events has remained uncertain due to the paucity of monocot genome sequence data outside the grass family (Poaceae). Phylogenomic analysis of protein-coding genes from sequenced genomes and transcriptome assemblies from 35 species, including representatives of all families within the Poales, has resolved the timing of rho and sigma relative to speciation events and placed tau prior to divergence of Asparagales and the commelinids but after divergence with eudicots. Examination of gene family phylogenies indicates that rho occurred just prior to the diversification of Poaceae and sigma occurred before early diversification of Poales lineages but after the Poales-commelinid split. Additional lineage-specific WGD events were identified on the basis of the transcriptome data. Gene families exhibiting high GC content are underrepresented among those with duplicate genes that persisted following these genome duplications. However, genome duplications had little overall influence on lineage-specific changes in the GC content of coding genes. Improved resolution of the timing of WGD events in monocot history provides evidence for the influence of polyploidization on functional evolution and species diversification. PMID:26988252

Residential Building Energy Code Field Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

R. Bartlett, M. Halverson, V. Mendon, J. Hathaway, Y. Xie

This document presents a methodology for assessing baseline energy efficiency in new single-family residential buildings and quantifying related savings potential. The approach was developed by Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy (DOE) Building Energy Codes Program with the objective of assisting states as they assess energy efficiency in residential buildings and implementation of their building energy codes, as well as to target areas for improvement through energy codes and broader energy-efficiency programs. It is also intended to facilitate a consistent and replicable approach to research studies of this type and establish a transparent data setmore » to represent baseline construction practices across U.S. states.« less

QX MAN: Q and X file manipulation

NASA Technical Reports Server (NTRS)

Krein, Mark A.

1992-01-01

QX MAN is a grid and solution file manipulation program written primarily for the PARC code and the GRIDGEN family of grid generation codes. QX MAN combines many of the features frequently encountered in grid generation, grid refinement, the setting-up of initial conditions, and post processing. QX MAN allows the user to manipulate single block and multi-block grids (and their accompanying solution files) by splitting, concatenating, rotating, translating, re-scaling, and stripping or adding points. In addition, QX MAN can be used to generate an initial solution file for the PARC code. The code was written to provide several formats for input and output in order for it to be useful in a broad spectrum of applications.

National Cost-effectiveness of ASHRAE Standard 90.1-2010 Compared to ASHRAE Standard 90.1-2007

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thornton, Brian; Halverson, Mark A.; Myer, Michael

Pacific Northwest National Laboratory (PNNL) completed this project for the U.S. Department of Energy’s (DOE’s) Building Energy Codes Program (BECP). DOE’s BECP supports upgrading building energy codes and standards, and the states’ adoption, implementation, and enforcement of upgraded codes and standards. Building energy codes and standards set minimum requirements for energy-efficient design and construction for new and renovated buildings, and impact energy use and greenhouse gas emissions for the life of buildings. Continuous improvement of building energy efficiency is achieved by periodically upgrading energy codes and standards. Ensuring that changes in the code that may alter costs (for building components,more » initial purchase and installation, replacement, maintenance and energy) are cost-effective encourages their acceptance and implementation. ANSI/ASHRAE/IESNA Standard 90.1 is the energy standard for commercial and multi-family residential buildings over three floors.« less

Cost-effectiveness of ASHRAE Standard 90.1-2010 Compared to ASHRAE Standard 90.1-2007

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thornton, Brian A.; Halverson, Mark A.; Myer, Michael

Pacific Northwest National Laboratory (PNNL) completed this project for the U.S. Department of Energy’s (DOE’s) Building Energy Codes Program (BECP). DOE’s BECP supports upgrading building energy codes and standards, and the states’ adoption, implementation, and enforcement of upgraded codes and standards. Building energy codes and standards set minimum requirements for energy-efficient design and construction for new and renovated buildings, and impact energy use and greenhouse gas emissions for the life of buildings. Continuous improvement of building energy efficiency is achieved by periodically upgrading energy codes and standards. Ensuring that changes in the code that may alter costs (for building components,more » initial purchase and installation, replacement, maintenance and energy) are cost-effective encourages their acceptance and implementation. ANSI/ASHRAE/IESNA Standard 90.1 is the energy standard for commercial and multi-family residential buildings over three floors.« less

RESRAD model presentation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, C.; Faillace, E.; Chen, S.Y.

RESRAD was one of the multimedia models selected by the US Nuclear Regulatory Commission (NRC) to include in its workshop on radiation dose modeling and demonstration of compliance with the radiological criteria for license termination. This paper is a summary of the presentation made at the workshop and focuses on the 10 questions the NRC distributed to all participants prior to the workshop. The code selection criteria, which were solicited by the NRC, for demonstrating compliance with the license termination rule are also included. Among the RESRAD family of codes, RESRAD and RESRAD-BUILD are designed for evaluating radiological contamination inmore » soils and in buildings. Many documents have been published to support the use of these codes. This paper focuses on these two codes. The pathways considered, the databases and parameters used, quality control and quality assurance, benchmarking, verification and validation of these codes, and capabilities as well as limitations of these codes are discussed in detail.« less

High mutation detection rate in TCOF1 among Treacher Collins syndrome patients reveals clustering of mutations and 16 novel pathogenic changes.

PubMed

Splendore, A; Silva, E O; Alonso, L G; Richieri-Costa, A; Alonso, N; Rosa, A; Carakushanky, G; Cavalcanti, D P; Brunoni, D; Passos-Bueno, M R

2000-10-01

Twenty-eight families with a clinical diagnosis of Treacher Collins syndrome were screened for mutations in the 25 coding exons of TCOF1 and their adjacent splice junctions through SSCP and direct sequencing. Pathogenic mutations were detected in 26 patients, yielding the highest detection rate reported so far for this disease (93%) and bringing the number of known disease-causing mutations from 35 to 51. This is the first report to describe clustering of pathogenic mutations. Thirteen novel polymorphic alterations were characterized, confirming previous reports that TCOF1 has an unusually high rate of single-nucleotide polymorphisms (SNPs) within its coding region. We suggest a possible different mechanism leading to TCS or genetic heterogeneity for this condition, as we identified two families with no apparent pathogenic mutation in the gene. Furthermore, our data confirm the absence of genotype-phenotype correlation and reinforce that the apparent anticipation often observed in TCS families is due to ascertainment bias. Copyright 2000 Wiley-Liss, Inc.

Cloning and sequence analysis of Hemonchus contortus HC58cDNA.

PubMed

Muleke, Charles I; Ruofeng, Yan; Lixin, Xu; Xinwen, Bo; Xiangrui, Li

2007-06-01

The complete coding sequence of Hemonchus contortus HC58cDNA was generated by rapid amplification of cDNA ends and polymerase chain reaction using primers based on the 5' and 3' ends of the parasite mRNA, accession no. AF305964. The HC58cDNA gene was 851 bp long, with open reading frame of 717 bp, precursors to 239 amino acids coding for approximately 27 kDa protein. Analysis of amino acid sequence revealed conserved residues of cysteine, histidine, asparagine, occluding loop pattern, hemoglobinase motif and glutamine of the oxyanion hole characteristic of cathepsin B like proteases (CBL). Comparison of the predicted amino acid sequences showed the protein shared 33.5-58.7% identity to cathepsin B homologues in the papain clan CA family (family C1). Phylogenetic analysis revealed close evolutionary proximity of the protein sequence to counterpart sequences in the CBL, suggesting that HC58cDNA was a member of the papain family.

Tax Breaks for College: Current and Proposed Tax Provisions That Help Families Meet College Costs.

ERIC Educational Resources Information Center

Hauptman, Arthur M.; Gladieux, Lawrence E.

The nature and scope of tax policies that affect higher education are sketched, concentrating on the provisions of the tax code that directly help families finance college costs. Attention is directed to: proposals to expand the range of tax benefits for higher education, the merits of existing and proposed tax schemes in times of reduced federal…

78 FR 54647 - Change in Bank Control Notices; Acquisitions of Shares of a Bank or Bank Holding Company

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-05

... September 18, 2013. A. Federal Reserve Bank of Atlanta (Chapelle Davis, Assistant Vice President) 1000..., Mark G. Morse Family Trust, Jennifer L. Parr, Jennifer L. Family Trust, Trust L. Matthews, and Tracy L... Board. [FR Doc. 2013-21480 Filed 9-4-13; 8:45 am] BILLING CODE 6210-01-P ...

Parental Psychological Control and Autonomy Granting: Distinctions and Associations with Child and Family Functioning.

PubMed

Kunz, Jennifer Hauser; Grych, John H

2013-04-01

OBJECTIVE: This study utilized an observational coding scheme to identify parenting behavior reflecting psychological control and autonomy granting and examined relations between these parenting dimensions and indices of child and family functioning. DESIGN: A community sample of 90 preadolescents (aged 10.5 to 12 years) and both of their parents engaged in a triadic interaction that was coded for parental psychological control and autonomy granting. Participants also completed measures of child adjustment, interparental conflict, and triangulation. RESULTS: Factor analyses indicated that a two-factor model better fit the data than a one-factor model, suggesting that psychological control and autonomy granting are best conceptualized as independent but related constructs. Parental psychological control and autonomy granting exhibited some shared and some unique correlates with indices of child and family functioning. Hierarchical regressions revealed significant interactions between these dimensions, suggesting that the strength of some associations between parents' use of psychological control and youth adjustment problems depends on the level of autonomy granting exhibited by the parent. CONCLUSIONS: By examining psychological control and autonomy granting simultaneously as unique constructs, this study identifies patterns of psychological control and autonomy granting that undermine youth adjustment. Findings inform targeted intervention efforts for families of preadolescent youth.

A Transactional Approach to Preventing Early Childhood Neglect: The Family Check-Up as a Public Health Strategy

PubMed Central

Dishion, Thomas J.; Mun, Chung Jung; Drake, Emily C.; Tein, Jenn-Yun; Shaw, Daniel S.; Wilson, Melvin

2016-01-01

This study examined the hypothesis that a brief, strengths-based home visiting strategy can promote positive engagement between caregiver and child and thereby reduce various forms of early childhood neglect. A total of 731 low-income families receiving services through the Women, Infants, and Children Nutritional Supplement (WIC) program were randomized to WIC as usual or the Family Check-Up (FCU) intervention. Assessments and intervention services were delivered in the home environment at ages 2, 3, 4, and 5. During the assessments, staff videotaped caregiver–child interactions and rated various features of the home environment, including the physical appropriateness of the home setting for children. Trained observers later coded the videotapes, unaware of the family’s intervention condition. Specific caregiver–child interaction patterns were coded and macro ratings were made of the caregiver’s affection, monitoring, and involvement with the child. An intention-to-treat design revealed that randomization to the FCU increased duration of positive engagement between caregivers and children by age 3, which in turn was prognostic of less neglect of the child at age 4, controlling for family adversity. It was also found that family adversity moderated the impact of the intervention, such that the families with the most adverse circumstances were highly responsive to the intervention. Families with the highest levels of adversity exhibited the strongest mediation between positive engagement and reduction of neglect. Findings are discussed with respect to developmental theory and their potential implications for a public health approach to the prevention of early-childhood maltreatment. PMID:26535950

Barriers Against Implementing Blunt Abdominal Trauma Guidelines in a Hospital: A Qualitative Study.

PubMed

Zaboli, Rouhollah; Tofighi, Shahram; Aghighi, Ali; Shokouh, Seyyed Javad Hosaini; Naraghi, Nader; Goodarzi, Hassan

2016-08-01

Clinical practice guidelines are structured recommendations that help physicians and patients to make proper decisions when dealing with a specific clinical condition. Because blunt abdominal trauma causes a various range of mild, single-system, and multisystem injuries, early detection will help to reduce mortality and resulting disability. Emergency treatment should be initiated based on CPGs. This study aimed to determine the variables affecting implementing blunt abdominal trauma CPGs in an Iranian hospital. This study was conducted as a qualitative and phenomenology study in the Family Hospital in Tehran (Iran) in 2015. The research population included eight experts and key people in the area of blunt abdominal trauma clinical practice guidelines. Sampling was based on purposive and nonrandom methods. A semistructured interview was done for the data collection. A framework method was applied for the data analysis by using Atlas.ti software. After framework analyzing and various reviewing and deleting and combining the codes from 251 codes obtained, 15 families and five super families were extracted, including technical knowledge barriers, economical barriers, barriers related to deployment and monitoring, political will barriers, and managing barriers. Structural reform is needed for eliminating the defects available in the healthcare system. As with most of the codes, subconcepts and concepts are classified into the field of human resources; it seems that the education and knowledge will be more important than other resources such as capital and equipment.

The complete chloroplast genome of Cinnamomum camphora and its comparison with related Lauraceae species.

PubMed

Chen, Caihui; Zheng, Yongjie; Liu, Sian; Zhong, Yongda; Wu, Yanfang; Li, Jiang; Xu, Li-An; Xu, Meng

2017-01-01

Cinnamomum camphora , a member of the Lauraceae family, is a valuable aromatic and timber tree that is indigenous to the south of China and Japan. All parts of Cinnamomum camphora have secretory cells containing different volatile chemical compounds that are utilized as herbal medicines and essential oils. Here, we reported the complete sequencing of the chloroplast genome of Cinnamomum camphora using illumina technology. The chloroplast genome of Cinnamomum camphora is 152,570 bp in length and characterized by a relatively conserved quadripartite structure containing a large single copy region of 93,705 bp, a small single copy region of 19,093 bp and two inverted repeat (IR) regions of 19,886 bp. Overall, the genome contained 123 coding regions, of which 15 were repeated in the IR regions. An analysis of chloroplast sequence divergence revealed that the small single copy region was highly variable among the different genera in the Lauraceae family. A total of 40 repeat structures and 83 simple sequence repeats were detected in both the coding and non-coding regions. A phylogenetic analysis indicated that Calycanthus is most closely related to Lauraceae , both being members of Laurales , which forms a sister group to Magnoliids . The complete sequence of the chloroplast of Cinnamomum camphora will aid in in-depth taxonomical studies of the Lauraceae family in the future. The genetic sequence information will also have valuable applications for chloroplast genetic engineering.

Molecular Evolution of Aminoacyl tRNA Synthetase Proteins in the Early History of Life

NASA Astrophysics Data System (ADS)

Fournier, Gregory P.; Andam, Cheryl P.; Alm, Eric J.; Gogarten, J. Peter

2011-12-01

Aminoacyl-tRNA synthetases (aaRS) consist of several families of functionally conserved proteins essential for translation and protein synthesis. Like nearly all components of the translation machinery, most aaRS families are universally distributed across cellular life, being inherited from the time of the Last Universal Common Ancestor (LUCA). However, unlike the rest of the translation machinery, aaRS have undergone numerous ancient horizontal gene transfers, with several independent events detected between domains, and some possibly involving lineages diverging before the time of LUCA. These transfers reveal the complexity of molecular evolution at this early time, and the chimeric nature of genomes within cells that gave rise to the major domains. Additionally, given the role of these protein families in defining the amino acids used for protein synthesis, sequence reconstruction of their pre-LUCA ancestors can reveal the evolutionary processes at work in the origin of the genetic code. In particular, sequence reconstructions of the paralog ancestors of isoleucyl- and valyl- RS provide strong empirical evidence that at least for this divergence, the genetic code did not co-evolve with the aaRSs; rather, both amino acids were already part of the genetic code before their cognate aaRSs diverged from their common ancestor. The implications of this observation for the early evolution of RNA-directed protein biosynthesis are discussed.

"We Are Strangers Walking Into Their Life-Changing Event": How Prehospital Providers Manage Emergency Calls at the End of Life.

PubMed

Waldrop, Deborah P; Clemency, Brian; Lindstrom, Heather A; Clemency Cordes, Colleen

2015-09-01

Emergency 911 calls are often made when the end stage of an advanced illness is accompanied by alarming symptoms and substantial anxiety for family caregivers, particularly when an approaching death is not anticipated. How prehospital providers (paramedics and emergency medical technicians) manage emergency calls near death influences how and where people will die, if their end-of-life choices are upheld and how appropriately health care resources are used. The purpose of this study was to explore and describe how prehospital providers assess and manage end-of-life emergency calls. In-depth and in-person interviews were conducted with 43 prehospital providers. Interviews were audiotaped, transcribed, and entered into ATLAS.ti for data management and coding. Qualitative data analysis involved systematic and axial coding to identify and describe emergent themes. Four themes illustrate the nature and dynamics of emergency end-of-life calls: 1) multifocal assessment (e.g., of the patient, family, and environment), 2) family responses (e.g., emotional, behavioral), 3) conflicts (e.g., missing do-not-resuscitate order, patient-family conflicts), and 4) management of the dying process (e.g., family witnessed resuscitation or asking family to leave, decisions about hospital transport). After a rapid comprehensive multifocal assessment, family responses and the existence of conflicts mediate decision making about possible interventions. The importance of managing symptom crises and stress responses that accompany the dying process is particularly germane to quality care at life's end. The results suggest the importance of increasing prehospital providers' abilities to uphold advance directives and patients' end-of-life wishes while managing family emotions near death. Copyright © 2015 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

How do parents of adolescent patients with anorexia nervosa interact with their child at mealtimes? A study of parental strategies used in the family meal session of family-based treatment.

PubMed

White, Hannah J; Haycraft, Emma; Madden, Sloane; Rhodes, Paul; Miskovic-Wheatley, Jane; Wallis, Andrew; Kohn, Michael; Meyer, Caroline

2015-01-01

To examine the range and frequency of parental mealtime strategies used during the family meal session of Family-Based Treatment (FBT) for adolescent anorexia nervosa, and to explore the relationships between parental mealtime strategies, mealtime emotional tone and parental 'success' at encouraging adolescent food consumption. Participants were 21 families with a child aged between 12 and 18 years receiving FBT for adolescent anorexia nervosa. Video recordings of the family meal session (FBT session two) were coded using the Family Mealtime Coding System adapted in this study for use with adolescents (FMCS-A) to identify frequency of parental strategies, emotional tone of the meal (measured by adolescent positive and negative vocalisations) and frequency of prompted mouthfuls consumed by the adolescent (measured by the number of mouthfuls consumed by the adolescent immediately following parental interactions). A range of parental mealtime strategies were in use. Those used repeatedly included direct eating prompts, non-direct eating prompts, physical prompts, and providing information or food-related choices. Several parental mealtime strategies (direct and non-direct eating prompts) were found to be consistently associated with the tone of adolescents' vocalisations and the number of mouthfuls consumed in response to a parental prompt. Despite associations with negativity from the adolescent, the use of food-related prompts (both verbal and physical) seems to be associated with increased eating. This indicates the potentially important role of parental control of eating. Following replication, these findings might provide a focus for therapists when supporting and coaching parents during the family meal session. © 2014 Wiley Periodicals, Inc.

Unraveling patterns of site-to-site synonymous rates variation and associated gene properties of protein domains and families.

PubMed

Dimitrieva, Slavica; Anisimova, Maria

2014-01-01

In protein-coding genes, synonymous mutations are often thought not to affect fitness and therefore are not subject to natural selection. Yet increasingly, cases of non-neutral evolution at certain synonymous sites were reported over the last decade. To evaluate the extent and the nature of site-specific selection on synonymous codons, we computed the site-to-site synonymous rate variation (SRV) and identified gene properties that make SRV more likely in a large database of protein-coding gene families and protein domains. To our knowledge, this is the first study that explores the determinants and patterns of the SRV in real data. We show that the SRV is widespread in the evolution of protein-coding sequences, putting in doubt the validity of the synonymous rate as a standard neutral proxy. While protein domains rarely undergo adaptive evolution, the SRV appears to play important role in optimizing the domain function at the level of DNA. In contrast, protein families are more likely to evolve by positive selection, but are less likely to exhibit SRV. Stronger SRV was detected in genes with stronger codon bias and tRNA reusage, those coding for proteins with larger number of interactions or forming larger number of structures, located in intracellular components and those involved in typically conserved complex processes and functions. Genes with extreme SRV show higher expression levels in nearly all tissues. This indicates that codon bias in a gene, which often correlates with gene expression, may often be a site-specific phenomenon regulating the speed of translation along the sequence, consistent with the co-translational folding hypothesis. Strikingly, genes with SRV were strongly overrepresented for metabolic pathways and those associated with several genetic diseases, particularly cancers and diabetes.

Antimicrobial peptide evolution in the Asiatic honey bee Apis cerana.

PubMed

Xu, Peng; Shi, Min; Chen, Xue-Xin

2009-01-01

The Asiatic honeybee, Apis cerana Fabricius, is an important honeybee species in Asian countries. It is still found in the wild, but is also one of the few bee species that can be domesticated. It has acquired some genetic advantages and significantly different biological characteristics compared with other Apis species. However, it has been less studied, and over the past two decades, has become a threatened species in China. We designed primers for the sequences of the four antimicrobial peptide cDNA gene families (abaecin, defensin, apidaecin, and hymenoptaecin) of the Western honeybee, Apis mellifera L. and identified all the antimicrobial peptide cDNA genes in the Asiatic honeybee for the first time. All the sequences were amplified by reverse transcriptase-polymerase chain reaction (RT-PCR). In all, 29 different defensin cDNA genes coding 7 different defensin peptides, 11 different abaecin cDNA genes coding 2 different abaecin peptides, 13 different apidaecin cDNA genes coding 4 apidaecin peptides and 34 different hymenoptaecin cDNA genes coding 13 different hymenoptaecin peptides were cloned and identified from the Asiatic honeybee adult workers. Detailed comparison of these four antimicrobial peptide gene families with those of the Western honeybee revealed that there are many similarities in the quantity and amino acid components of peptides in the abaecin, defensin and apidaecin families, while many more hymenoptaecin peptides are found in the Asiatic honeybee than those in the Western honeybee (13 versus 1). The results indicated that the Asiatic honeybee adult generated more variable antimicrobial peptides, especially hymenoptaecin peptides than the Western honeybee when stimulated by pathogens or injury. This suggests that, compared to the Western honeybee that has a longer history of domestication, selection on the Asiatic honeybee has favored the generation of more variable antimicrobial peptides as protection against pathogens.

[Placement of children and adolescents following seclusion and restraint actions–a study on family-court approvals of minors in youth welfare, child and adolescent psychiatry and jail according to Para. 1631 German Civil Code].

PubMed

Kölch, Michael; Vogel, Harald

2016-01-01

According to German law (Para. 1631b German Civil Code), the placement of children and adolescents following seclusion and restraint actions must be approved by a family court. We analyzed the family court data of a court district in Berlin (Tempelhof-Kreuzberg) concerning cases of “placement of minors” between 2008 and 2011. A total of 474 such procedures were discovered. After data clearing and correction of cases (e. g., because of emergency interventions of the youth welfare system taking children into custody according to Para. 42, German Civil Code VIII), 376 cases remained. Of these 376 procedures in the years 2008 to 2011, 127 cases concerned children and adolescents according to Para. 1631b German Civil Code, and 249 procedures were settled either by dismissal, withdrawal or by repealing the initial decision to place the child with restrain or seclusion by means of an interim order or by filing an appeal against the final decision. Of the 127 procedures, 68 concerned girls, who were on average slightly younger than boys (14.5 years vs. 15.1 years). In two thirds of the procedures, the children and adolescents were German citizens. The majority of youths involved were living at home at the time of the procedure, but in 15 % of the case the youths were homeless. Most of the adolescents were treated with restraint in child and adolescent psychiatry. The most frequently quoted reasons for seclusion were substance abuse, suicide risk and running away from home/being homeless.

Topics in the Sequential Design of Experiments

DTIC Science & Technology

1992-03-01

decision , unless so designated by other documentation. 12a. DISTRIBUTION /AVAILABIIUTY STATEMENT 12b. DISTRIBUTION CODE Approved for public release...3 0 1992 D 14. SUBJECT TERMS 15. NUMBER OF PAGES12 Design of Experiments, Renewal Theory , Sequential Testing 1 2. PRICE CODE Limit Theory , Local...distributions for one parameter exponential families," by Michael Woodroofe. Stntca, 2 (1991), 91-112. [6] "A non linear renewal theory for a functional of

Periodontal status and its association with self-reported hypertension in non-medical staff in a university teaching hospital in Nigeria.

PubMed

Umeizudike, K A; Ayanbadejo, P O; Onajole, A T; Umeizudike, T I; Alade, G O

2016-03-01

A growing body of evidence suggests a relationship between periodontal disease and non-communicable systemic diseases with rising prevalence in developing countries, Nigeria inclusive. To determine the periodontal status and its association with self-reported hypertension among non-medical staff in a university teaching hospital in Nigeria. A cross-sectional study was conducted among non-medical staff using self-administered questionnaires and periodontal clinical examination between July and August 2013. Multivariate analysis was explored to determine the independent variables associated with self-reported hypertension. P values < 0.05 were considered statistically significant. A total of 276 subjects were enrolled into the study. Shallow pockets (CPI code 3) constituted the predominant periodontal disease (46.7%), calculus (CPI code 2) 46%, bleeding gingiva (CPI code 1) in 3.3% and deep pockets ≥ 6mm (CPI code 4) in 2.2%. Self-reported hypertension was the most prevalent self-reported medical condition (18.1%) and found to be associated with periodontitis, increasing age, lower education, and a positive family history of hypertension. Periodontal disease was highly prevalent in this study. Self-reported hypertension was associated with periodontitis, older age, lower education and a positive family history. Periodic periodontal examination and regular blood pressure assessment for non-medical staff is recommended.

Shannon information entropy in the canonical genetic code.

PubMed

Nemzer, Louis R

2017-02-21

The Shannon entropy measures the expected information value of messages. As with thermodynamic entropy, the Shannon entropy is only defined within a system that identifies at the outset the collections of possible messages, analogous to microstates, that will be considered indistinguishable macrostates. This fundamental insight is applied here for the first time to amino acid alphabets, which group the twenty common amino acids into families based on chemical and physical similarities. To evaluate these schemas objectively, a novel quantitative method is introduced based the inherent redundancy in the canonical genetic code. Each alphabet is taken as a separate system that partitions the 64 possible RNA codons, the microstates, into families, the macrostates. By calculating the normalized mutual information, which measures the reduction in Shannon entropy, conveyed by single nucleotide messages, groupings that best leverage this aspect of fault tolerance in the code are identified. The relative importance of properties related to protein folding - like hydropathy and size - and function, including side-chain acidity, can also be estimated. This approach allows the quantification of the average information value of nucleotide positions, which can shed light on the coevolution of the canonical genetic code with the tRNA-protein translation mechanism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preface to the Special Issue on TOUGH Symposium 2015

NASA Astrophysics Data System (ADS)

Blanco-Martín, Laura

2017-11-01

The TOUGH Symposium 2015 was held in Berkeley, California, September 28-30, 2015. The TOUGH family of codes, developed at the Energy Geosciences Division of Lawrence Berkeley National Laboratory (LBNL), is a suite of computer programs for the simulation of multiphase and multicomponent fluid and heat flows in porous and fractured media with applications in many geosciences fields, such as geothermal reservoir engineering, nuclear waste disposal, geological carbon sequestration, oil and gas reservoirs, gas hydrate research, vadose zone hydrology and environmental remediation. Since the first release in the 1980s, many modifications and enhancements have been continuously made to TOUGH and its various descendants (iTOUGH2, TOUGH+, TOUGH-MP, TOUGHREACT, TOUGH+HYDRATE, TMVOC...), at LBNL and elsewhere. Today, these codes are used worldwide in academia, government organizations and private companies in problems involving coupled hydrological, thermal, biogeochemical and geomechanical processes. The Symposia, organized every 2-3 years, bring together developers and users for an open exchange on recent code enhancements and applications. In 2015, the Symposium was attended by one hundred participants, representing thirty-four nationalities. This Special Issue in Computers & Geosciences gathers extended versions of selected Symposium proceedings related to (i) recent enhancements to the TOUGH family of codes and (ii) coupled flow and geomechanics processes modeling.

Identification of SNPs associated with muscle yield and quality traits using allelic-imbalance analyses of pooled RNA-Seq samples in rainbow trout.

PubMed

Al-Tobasei, Rafet; Ali, Ali; Leeds, Timothy D; Liu, Sixin; Palti, Yniv; Kenney, Brett; Salem, Mohamed

2017-08-07

Coding/functional SNPs change the biological function of a gene and, therefore, could serve as "large-effect" genetic markers. In this study, we used two bioinformatics pipelines, GATK and SAMtools, for discovering coding/functional SNPs with allelic-imbalances associated with total body weight, muscle yield, muscle fat content, shear force, and whiteness. Phenotypic data were collected for approximately 500 fish, representing 98 families (5 fish/family), from a growth-selected line, and the muscle transcriptome was sequenced from 22 families with divergent phenotypes (4 low- versus 4 high-ranked families per trait). GATK detected 59,112 putative SNPs; of these SNPs, 4798 showed allelic imbalances (>2.0 as an amplification and <0.5 as loss of heterozygosity). SAMtools detected 87,066 putative SNPs; and of them, 4962 had allelic imbalances between the low- and high-ranked families. Only 1829 SNPs with allelic imbalances were common between the two datasets, indicating significant differences in algorithms. The two datasets contained 7930 non-redundant SNPs of which 4439 mapped to 1498 protein-coding genes (with 6.4% non-synonymous SNPs) and 684 mapped to 295 lncRNAs. Validation of a subset of 92 SNPs revealed 1) 86.7-93.8% success rate in calling polymorphic SNPs and 2) 95.4% consistent matching between DNA and cDNA genotypes indicating a high rate of identifying SNPs with allelic imbalances. In addition, 4.64% SNPs revealed random monoallelic expression. Genome distribution of the SNPs with allelic imbalances exhibited high density for all five traits in several chromosomes, especially chromosome 9, 20 and 28. Most of the SNP-harboring genes were assigned to important growth-related metabolic pathways. These results demonstrate utility of RNA-Seq in assessing phenotype-associated allelic imbalances in pooled RNA-Seq samples. The SNPs identified in this study were included in a new SNP-Chip design (available from Affymetrix) for genomic and genetic analyses in rainbow trout.

Expansion by whole genome duplication and evolution of the sox gene family in teleost fish

PubMed Central

Naville, Magali; Volff, Jean-Nicolas

2017-01-01

It is now recognized that several rounds of whole genome duplication (WGD) have occurred during the evolution of vertebrates, but the link between WGDs and phenotypic diversification remains unsolved. We have investigated in this study the impact of the teleost-specific WGD on the evolution of the sox gene family in teleostean fishes. The sox gene family, which encodes for transcription factors, has essential role in morphology, physiology and behavior of vertebrates and teleosts, the current largest group of vertebrates. We have first redrawn the evolution of all sox genes identified in eleven teleost genomes using a comparative genomic approach including phylogenetic and synteny analyses. We noticed, compared to tetrapods, an important expansion of the sox family: 58% (11/19) of sox genes are duplicated in teleost genomes. Furthermore, all duplicated sox genes, except sox17 paralogs, are derived from the teleost-specific WGD. Then, focusing on five sox genes, analyzing the evolution of coding and non-coding sequences, as well as the expression patterns in fish embryos and adult tissues, we demonstrated that these paralogs followed lineage-specific evolutionary trajectories in teleost genomes. This work, based on whole genome data from multiple teleostean species, supports the contribution of WGDs to the expansion of gene families, as well as to the emergence of genomic differences between lineages that might promote genetic and phenotypic diversity in teleosts. PMID:28738066

If I am not for myself, who is for me? The experiences of older migrant home care recipients during their hospitalization.

PubMed

Shinan-Altman, Shiri; Ayalon, Liat

2017-02-01

Hospitalization is a major risk for older adults; therefore, it is crucial to provide the appropriate treatment during hospitalization. This study examined hospitalized older adults' perceptions regarding three groups of treatment providers: nursing staff, family members, migrant home care workers. Qualitative interviews were conducted with 17 hospitalized older adults. Data were gathered by in-depth interviews. Content analysis included open coding, axial coding and integration of the main findings using constant comparisons. Three themes emerged: (1) 'What is my worth?' This theme was focused on the participants' perceptions of themselves as helpless and dependent on others. (2) 'What would I do without them?' This theme referred to the perception of the migrant home care workers and nursing staff as essential. It meant immense gratitude, but also a sense of dependency on paid caregivers. (3) 'They have their own busy life.' This theme concerned participants' low treatment expectations from their family members due to their perception of their family members as having multiple obligations. Hospitalized older adults prefer to turn to paid caregivers rather than to their families. Findings are discussed in light of the tension between formal and informal care in countries that are transitioning from traditional family values to modern values, placing the care of older adults by paid caregivers.

Drawing dynamical and parameters planes of iterative families and methods.

PubMed

Chicharro, Francisco I; Cordero, Alicia; Torregrosa, Juan R

2013-01-01

The complex dynamical analysis of the parametric fourth-order Kim's iterative family is made on quadratic polynomials, showing the MATLAB codes generated to draw the fractal images necessary to complete the study. The parameter spaces associated with the free critical points have been analyzed, showing the stable (and unstable) regions where the selection of the parameter will provide us the excellent schemes (or dreadful ones).

Structural Estimation of Family Labor Supply with Taxes: Estimating a Continuous Hours Model Using a Direct Utility Specification

ERIC Educational Resources Information Center

Heim, Bradley T.

2009-01-01

This paper proposes a new method for estimating family labor supply in the presence of taxes. This method accounts for continuous hours choices, measurement error, unobserved heterogeneity in tastes for work, the nonlinear form of the tax code, and fixed costs of work in one comprehensive specification. Estimated on data from the 2001 PSID, the…

10 CFR 434.517 - HVAC systems and equipment.

Code of Federal Regulations, 2014 CFR

2014-01-01

... DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE.... >3 stories 6 Note 6. Restaurant 1 or 3 Note 1. Health: a. Nursing Home (any size) 2 or 7 Note 7. b. ≤15,000 ft 2 1 c. 50,000 ft 2 5 Note 2, 3. Multi-family High Rise Residential >3 stories 7 1 Space and...

10 CFR 434.517 - HVAC systems and equipment.

Code of Federal Regulations, 2012 CFR

2012-01-01

... DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE.... >3 stories 6 Note 6. Restaurant 1 or 3 Note 1. Health: a. Nursing Home (any size) 2 or 7 Note 7. b. ≤15,000 ft 2 1 c. 50,000 ft 2 5 Note 2, 3. Multi-family High Rise Residential >3 stories 7 1 Space and...

10 CFR 434.517 - HVAC systems and equipment.

Code of Federal Regulations, 2011 CFR

2011-01-01

... DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE.... >3 stories 6 Note 6. Restaurant 1 or 3 Note 1. Health: a. Nursing Home (any size) 2 or 7 Note 7. b. ≤15,000 ft 2 1 c. 50,000 ft 2 5 Note 2, 3. Multi-family High Rise Residential >3 stories 7 1 Space and...

10 CFR 434.517 - HVAC systems and equipment.

Code of Federal Regulations, 2013 CFR

2013-01-01

... DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE.... >3 stories 6 Note 6. Restaurant 1 or 3 Note 1. Health: a. Nursing Home (any size) 2 or 7 Note 7. b. ≤15,000 ft 2 1 c. 50,000 ft 2 5 Note 2, 3. Multi-family High Rise Residential >3 stories 7 1 Space and...

Children's Perceptions of Family Relationships as Assessed in a Doll Story Completion Task: Links to Parenting, Social Competence, and Externalizing Behavior

ERIC Educational Resources Information Center

Laible, Deborah; Carlo, Gustavo; Torquati, Julia; Ontai, Lenna

2004-01-01

This study was designed to examine the links between parenting, children's perceptions of family relationships, and children's social behavior. Seventy-four children (M age = 6.01 years; 39 boys; 35 girls) and their parents took part in the study. Children completed relationship-oriented doll stories that were coded for coherence, prosocial…

Whole Genome Sequencing Identifies a 78 kb Insertion from Chromosome 8 as the Cause of Charcot-Marie-Tooth Neuropathy CMTX3

PubMed Central

Brewer, Megan H.; Chaudhry, Rabia; Qi, Jessica; Kidambi, Aditi; Drew, Alexander P.; Ryan, Monique M.; Subramanian, Gopinath M.; Young, Helen K.; Zuchner, Stephan; Reddel, Stephen W.; Nicholson, Garth A.; Kennerson, Marina L.

2016-01-01

With the advent of whole exome sequencing, cases where no pathogenic coding mutations can be found are increasingly being observed in many diseases. In two large, distantly-related families that mapped to the Charcot-Marie-Tooth neuropathy CMTX3 locus at chromosome Xq26.3-q27.3, all coding mutations were excluded. Using whole genome sequencing we found a large DNA interchromosomal insertion within the CMTX3 locus. The 78 kb insertion originates from chromosome 8q24.3, segregates fully with the disease in the two families, and is absent from the general population as well as 627 neurologically normal chromosomes from in-house controls. Large insertions into chromosome Xq27.1 are known to cause a range of diseases and this is the first neuropathy phenotype caused by an interchromosomal insertion at this locus. The CMTX3 insertion represents an understudied pathogenic structural variation mechanism for inherited peripheral neuropathies. Our finding highlights the importance of considering all structural variation types when studying unsolved inherited peripheral neuropathy cases with no pathogenic coding mutations. PMID:27438001

Characterization of the complete mitochondrial genome of Marshallagia marshalli and phylogenetic implications for the superfamily Trichostrongyloidea.

PubMed

Sun, Miao-Miao; Han, Liang; Zhang, Fu-Kai; Zhou, Dong-Hui; Wang, Shu-Qing; Ma, Jun; Zhu, Xing-Quan; Liu, Guo-Hua

2018-01-01

Marshallagia marshalli (Nematoda: Trichostrongylidae) infection can lead to serious parasitic gastroenteritis in sheep, goat, and wild ruminant, causing significant socioeconomic losses worldwide. Up to now, the study concerning the molecular biology of M. marshalli is limited. Herein, we sequenced the complete mitochondrial (mt) genome of M. marshalli and examined its phylogenetic relationship with selected members of the superfamily Trichostrongyloidea using Bayesian inference (BI) based on concatenated mt amino acid sequence datasets. The complete mt genome sequence of M. marshalli is 13,891 bp, including 12 protein-coding genes, 22 transfer RNA genes, and 2 ribosomal RNA genes. All protein-coding genes are transcribed in the same direction. Phylogenetic analyses based on concatenated amino acid sequences of the 12 protein-coding genes supported the monophylies of the families Haemonchidae, Molineidae, and Dictyocaulidae with strong statistical support, but rejected the monophyly of the family Trichostrongylidae. The determination of the complete mt genome sequence of M. marshalli provides novel genetic markers for studying the systematics, population genetics, and molecular epidemiology of M. marshalli and its congeners.

Evaluation of genetic variations in miRNA-binding sites of BRCA1 and BRCA2 genes as risk factors for the development of early-onset and/or familial breast cancer.

PubMed

Erturk, Elif; Cecener, Gulsah; Polatkan, Volkan; Gokgoz, Sehsuvar; Egeli, Unal; Tunca, Berrin; Tezcan, Gulcin; Demirdogen, Elif; Ak, Secil; Tasdelen, Ismet

2014-01-01

Although genetic markers identifying women at an increased risk of developing breast cancer exist, the majority of inherited risk factors remain elusive. Mutations in the BRCA1/BRCA2 gene confer a substantial increase in breast cancer risk, yet routine clinical genetic screening is limited to the coding regions and intron- exon boundaries, precluding the identification of mutations in noncoding and untranslated regions. Because 3' untranslated region (3'UTR) polymorphisms disrupting microRNA (miRNA) binding can be functional and can act as genetic markers of cancer risk, we aimed to determine genetic variation in the 3'UTR of BRCA1/BRCA2 in familial and early-onset breast cancer patients with and without mutations in the coding regions of BRCA1/ BRCA2 and to identify specific 3'UTR variants that may be risk factors for cancer development. The 3'UTRs of the BRCA1 and BRCA2 genes were screened by heteroduplex analysis and DNA sequencing in 100 patients from 46 BRCA1/2 families, 54 non-BRCA1/2 families, and 47 geographically matched controls. Two polymorphisms were identified. SNPs c.*1287C>T (rs12516) (BRCA1) and c.*105A>C (rs15869) (BRCA2) were identified in 27% and 24% of patients, respectively. These 2 variants were also identified in controls with no family history of cancer (23.4% and 23.4%, respectively). In comparison to variations in the 3'UTR region of the BRCA1/2 genes and the BRCA1/2 mutational status in patients, there was a statistically significant relationship between the BRCA1 gene polymorphism c.*1287C>T (rs12516) and BRCA1 mutations (p=0.035) by Fisher's Exact Test. SNP c.*1287C>T (rs12516) of the BRCA1 gene may have potential use as a genetic marker of an increased risk of developing breast cancer and likely represents a non-coding sequence variation in BRCA1 that impacts BRCA1 function and leads to increased early-onset and/or familial breast cancer risk in the Turkish population.

Structural and functional studies of a family of Dictyostelium discoideum developmentally regulated, prestalk genes coding for small proteins.

PubMed

Vicente, Juan J; Galardi-Castilla, María; Escalante, Ricardo; Sastre, Leandro

2008-01-03

The social amoeba Dictyostelium discoideum executes a multicellular development program upon starvation. This morphogenetic process requires the differential regulation of a large number of genes and is coordinated by extracellular signals. The MADS-box transcription factor SrfA is required for several stages of development, including slug migration and spore terminal differentiation. Subtractive hybridization allowed the isolation of a gene, sigN (SrfA-induced gene N), that was dependent on the transcription factor SrfA for expression at the slug stage of development. Homology searches detected the existence of a large family of sigN-related genes in the Dictyostelium discoideum genome. The 13 most similar genes are grouped in two regions of chromosome 2 and have been named Group1 and Group2 sigN genes. The putative encoded proteins are 87-89 amino acids long. All these genes have a similar structure, composed of a first exon containing a 13 nucleotides long open reading frame and a second exon comprising the remaining of the putative coding region. The expression of these genes is induced at10 hours of development. Analyses of their promoter regions indicate that these genes are expressed in the prestalk region of developing structures. The addition of antibodies raised against SigN Group 2 proteins induced disintegration of multi-cellular structures at the mound stage of development. A large family of genes coding for small proteins has been identified in D. discoideum. Two groups of very similar genes from this family have been shown to be specifically expressed in prestalk cells during development. Functional studies using antibodies raised against Group 2 SigN proteins indicate that these genes could play a role during multicellular development.

Structure of genes for dermaseptins B, antimicrobial peptides from frog skin. Exon 1-encoded prepropeptide is conserved in genes for peptides of highly different structures and activities.

PubMed

Vouille, V; Amiche, M; Nicolas, P

1997-09-01

We cloned the genes of two members of the dermaseptin family, broad-spectrum antimicrobial peptides isolated from the skin of the arboreal frog Phyllomedusa bicolor. The dermaseptin gene Drg2 has a 2-exon coding structure interrupted by a small 137-bp intron, wherein exon 1 encoded a 22-residue hydrophobic signal peptide and the first three amino acids of the acidic propiece; exon 2 contained the 18 additional acidic residues of the propiece plus a typical prohormone processing signal Lys-Arg and a 32-residue dermaseptin progenitor sequence. The dermaseptin genes Drg2 and Drg1g2 have conserved sequences at both untranslated ends and in the first and second coding exons. In contrast, Drg1g2 comprises a third coding exon for a short version of the acidic propiece and a second dermaseptin progenitor sequence. Structural conservation between the two genes suggests that Drg1g2 arose recently from an ancestral Drg2-like gene through amplification of part of the second coding exon and 3'-untranslated region. Analysis of the cDNAs coding precursors for several frog skin peptides of highly different structures and activities demonstrates that the signal peptides and part of the acidic propieces are encoded by conserved nucleotides encompassed by the first coding exon of the dermaseptin genes. The organization of the genes that belong to this family, with the signal peptide and the progenitor sequence on separate exons, permits strikingly different peptides to be directed into the secretory pathway. The recruitment of such a homologous 'secretory' exon by otherwise non-homologous genes may have been an early event in the evolution of amphibian.

Familial discoid lupus erythematosus associated with heterozygote C2 deficiency.

PubMed

Belin, D C; Bordwell, B J; Einarson, M E; McLean, R H; Weinstein, A; Yunis, E J; Rothfield, N F

1980-08-01

Two siblings with chronic discoid lupus erythematosus and several family members were found with heterozygous C2 deficiency. An association with histocompatibility markers HLA-B18 and HLA-Dw2 was demonstrated, and the slow allotype of factor B was present. Linkage studies in this family suggested a close linkage between the C2 deficiency gene and genes coding for B18, Dw2, and BfS antigens. One HLA-ACB/DBf recombinant was observed showing closer linkage between HLA-D and Bf than between HLA-B and Bf.

Molecular cloning of a Candida albicans gene (SSB1) coding for a protein related to the Hsp70 family.

PubMed

Maneu, V; Cervera, A M; Martinez, J P; Gozalbo, D

1997-06-15

We have cloned and sequenced a Candida albicans gene (SSB1) encoding a potential member of the heat-shock protein seventy (hsp70) family. The protein encoded by this gene contains 613 amino acids and shows a high degree (85%) of sequence identity to the ssb subfamily (ssb1 and ssb2) of the Saccharomyces cerevisiae hsp70 family. The transcribed mRNA (2.1 kb) is present in similar amounts both in yeast and germ tube cells of C. albicans.

Rare coding variants in Phospholipase D3 (PLD3) confer risk for Alzheimer's disease

PubMed Central

Cruchaga, Carlos; Benitez, Bruno A.; Cai, Yefei; Guerreiro, Rita; Harari, Oscar; Norton, Joanne; Budde, John; Bertelsen, Sarah; Jeng, Amanda T.; Cooper, Breanna; Skorupa, Tara; Carrell, David; Levitch, Denise; Hsu, Simon; Choi, Jiyoon; Ryten, Mina; Sassi, Celeste; Bras, Jose; Gibbs, Raphael J.; Hernandez, Dena G.; Lupton, Michelle K.; Powell, John; Forabosco, Paola; Ridge, Perry G.; Corcoran, Christopher D.; Tschanz, JoAnn T.; Norton, Maria C.; Munger, Ronald G.; Schmutz, Cameron; Leary, Maegan; Demirci, F. Yesim; Bamne, Mikhil N.; Wang, Xingbin; Lopez, Oscar L.; Ganguli, Mary; Medway, Christopher; Turton, James; Lord, Jenny; Braae, Anne; Barber, Imelda; Brown, Kristelle; Pastor, Pau; Lorenzo-Betancor, Oswaldo; Brkanac, Zoran; Scott, Erick; Topol, Eric; Morgan, Kevin; Rogaeva, Ekaterina; Singleton, Andy; Hardy, John; Kamboh, M. Ilyas; George-Hyslop, Peter St; Cairns, Nigel; Morris, John C.; Kauwe, John S.K.; Goate, Alison M.

2014-01-01

Genome-wide association studies (GWAS) have identified several risk variants for late-onset Alzheimer's disease (LOAD)1,2. These common variants have replicable but small effects on LOAD risk and generally do not have obvious functional effects. Low-frequency coding variants, not detected by GWAS, are predicted to include functional variants with larger effects on risk. To identify low frequency coding variants with large effects on LOAD risk, we performed whole exome-sequencing (WES) in 14 large LOAD families and follow-up analyses of the candidate variants in several large case-control datasets. A rare variant in PLD3 (phospholipase-D family, member 3, rs145999145; V232M) segregated with disease status in two independent families and doubled risk for AD in seven independent case-control series (V232M meta-analysis; OR= 2.10, CI=1.47-2.99; p= 2.93×10-5, 11,354 cases and controls of European-descent). Gene-based burden analyses in 4,387 cases and controls of European-descent and 302 African American cases and controls, with complete sequence data for PLD3, indicate that several variants in this gene increase risk for AD in both populations (EA: OR= 2.75, CI=2.05-3.68; p=1.44×10-11, AA: OR= 5.48, CI=1.77-16.92; p=1.40×10-3). PLD3 is highly expressed in brain regions vulnerable to AD pathology, including hippocampus and cortex, and is expressed at lower levels in neurons from AD brains compared to control brains (p=8.10×10-10). Over-expression of PLD3 leads to a significant decrease in intracellular APP and extracellular Aβ42 and Aβ40, while knock-down of PLD3 leads to a significant increase in extracellular Aβ42 and Aβ40. Together, our genetic and functional data indicate that carriers of PLD3 coding variants have a two-fold increased risk for LOAD and that PLD3 influences APP processing. This study provides an example of how densely affected families may be used to identify rare variants with large effects on risk for disease or other complex traits. PMID:24336208

Moderate Deviation Analysis for Classical Communication over Quantum Channels

NASA Astrophysics Data System (ADS)

Chubb, Christopher T.; Tan, Vincent Y. F.; Tomamichel, Marco

2017-11-01

We analyse families of codes for classical data transmission over quantum channels that have both a vanishing probability of error and a code rate approaching capacity as the code length increases. To characterise the fundamental tradeoff between decoding error, code rate and code length for such codes we introduce a quantum generalisation of the moderate deviation analysis proposed by Altŭg and Wagner as well as Polyanskiy and Verdú. We derive such a tradeoff for classical-quantum (as well as image-additive) channels in terms of the channel capacity and the channel dispersion, giving further evidence that the latter quantity characterises the necessary backoff from capacity when transmitting finite blocks of classical data. To derive these results we also study asymmetric binary quantum hypothesis testing in the moderate deviations regime. Due to the central importance of the latter task, we expect that our techniques will find further applications in the analysis of other quantum information processing tasks.

Seeking help for depression from family and friends: a qualitative analysis of perceived advantages and disadvantages.

PubMed

Griffiths, Kathleen M; Crisp, Dimity A; Barney, Lisa; Reid, Russell

2011-12-15

People with depression often seek help from family and friends and public health campaigns frequently encourage such help seeking behaviours. However, there has been little systematically collected empirical data concerning the effects of such informal help seeking. The current study sought to investigate the views of consumers about the advantages and disadvantages of seeking support from family and friends for depression. Participants were the subset of 417 respondents to a survey, sent to 7000 randomly selected members of an Australian electoral community, who indicated that they had sought help for depression from family or friends. One item on the survey asked participants to indicate the advantages or disadvantages of seeking help from family or friends. A coding system was developed based on a content analysis of the responses to the item. Each of the responses was then coded by two raters. Respondents identified both advantages and disadvantages of seeking support from friends. The most commonly cited advantage was social support (n = 282) including emotional support (n = 154), informational support (n = 93), companionship support (n = 36) and instrumental support (n = 23). Other advantages related to family's or friend's background knowledge of the person and their circumstances (n = 72), the opportunity to offload the burden associated with depression (n = 62), the personal attributes of family and friends (n = 49), their accessibility (n = 36), and the opportunity to educate family and friends and increase their awareness about the respondent's depression (n = 30). The most commonly cited disadvantages were stigma (n = 53), inappropriate support (n = 45), the family member's lack of knowledge, training and expertise (n = 32) and the adverse impact of the help seeking on the family/friend (n = 20) and the relationship (n = 18). Family and friends are well placed to provide support which consumers perceive to be positive and which can assist them in obtaining formal mental health treatment. However, the input of some family members may be unhelpful or toxic. There may be benefits in undertaking community education and destigmatisation programs which target carers.

Seeking help for depression from family and friends: A qualitative analysis of perceived advantages and disadvantages

PubMed Central

2011-01-01

Background People with depression often seek help from family and friends and public health campaigns frequently encourage such help seeking behaviours. However, there has been little systematically collected empirical data concerning the effects of such informal help seeking. The current study sought to investigate the views of consumers about the advantages and disadvantages of seeking support from family and friends for depression. Methods Participants were the subset of 417 respondents to a survey, sent to 7000 randomly selected members of an Australian electoral community, who indicated that they had sought help for depression from family or friends. One item on the survey asked participants to indicate the advantages or disadvantages of seeking help from family or friends. A coding system was developed based on a content analysis of the responses to the item. Each of the responses was then coded by two raters. Results Respondents identified both advantages and disadvantages of seeking support from friends. The most commonly cited advantage was social support (n = 282) including emotional support (n = 154), informational support (n = 93), companionship support (n = 36) and instrumental support (n = 23). Other advantages related to family's or friend's background knowledge of the person and their circumstances (n = 72), the opportunity to offload the burden associated with depression (n = 62), the personal attributes of family and friends (n = 49), their accessibility (n = 36), and the opportunity to educate family and friends and increase their awareness about the respondent's depression (n = 30). The most commonly cited disadvantages were stigma (n = 53), inappropriate support (n = 45), the family member's lack of knowledge, training and expertise (n = 32) and the adverse impact of the help seeking on the family/friend (n = 20) and the relationship (n = 18). Conclusions Family and friends are well placed to provide support which consumers perceive to be positive and which can assist them in obtaining formal mental health treatment. However, the input of some family members may be unhelpful or toxic. There may be benefits in undertaking community education and destigmatisation programs which target carers. PMID:22171567

Society of Critical Care Medicine

MedlinePlus

... Liberation Sepsis ICU Management Coding and Billing ICU Design Workforce ICU REPORT Disaster ICU Benchmarking Tools International ... Family Award for Ethics Honorary Life Membership ICU Design Citation ICU Heroes Lifetime Achievement Norma J. Shoemaker ...

Aging Veterans and Posttraumatic Stress Symptoms

MedlinePlus

... Enter ZIP code here Aging Veterans and Posttraumatic Stress Symptoms Public This section is for Veterans, General Public, Family, & Friends Aging Veterans and Posttraumatic Stress Symptoms For many Veterans, memories of their wartime ...

28 CFR 540.101 - Procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

....g., size of family. (1) During the admission and orientation process, an inmate who chooses to have... changes on at least a quarterly basis. (c) Telephone access codes. An inmate may not possess another...

Valine-glutamine (VQ) motif coding genes are ancient and non-plant-specific with comprehensive expression regulation by various biotic and abiotic stresses.

PubMed

Jiang, Shu-Ye; Sevugan, Mayalagu; Ramachandran, Srinivasan

2018-05-09

Valine-glutamine (VQ) motif containing proteins play important roles in abiotic and biotic stress responses in plants. However, little is known about the origin and evolution as well as comprehensive expression regulation of the VQ gene family. In this study, we systematically surveyed this gene family in 50 plant genomes from algae, moss, gymnosperm and angiosperm and explored their presence in other species from animals, bacteria, fungi and viruses. No VQs were detected in all tested algae genomes and all genomes from moss, gymnosperm and angiosperm encode varying numbers of VQs. Interestingly, some of fungi, lower animals and bacteria also encode single to a few VQs. Thus, they are not plant-specific and should be regarded as an ancient family. Their family expansion was mainly due to segmental duplication followed by tandem duplication and mobile elements. Limited contribution of gene conversion was detected to the family evolution. Generally, VQs were very much conserved in their motif coding region and were under purifying selection. However, positive selection was also observed during species divergence. Many VQs were up- or down-regulated by various abiotic / biotic stresses and phytohormones in rice and Arabidopsis. They were also co-expressed with some of other stress-related genes. All of the expression data suggest a comprehensive expression regulation of the VQ gene family. We provide new insights into gene expansion, divergence, evolution and their expression regulation of this VQ family. VQs were detectable not only in plants but also in some of fungi, lower animals and bacteria, suggesting the evolutionary conservation and the ancient origin. Overall, VQs are non-plant-specific and play roles in abiotic / biotic responses or other biological processes through comprehensive expression regulation.

Coding, Constant Comparisons, and Core Categories: A Worked Example for Novice Constructivist Grounded Theorists.

PubMed

Giles, Tracey M; de Lacey, Sheryl; Muir-Cochrane, Eimear

2016-01-01

Grounded theory method has been described extensively in the literature. Yet, the varying processes portrayed can be confusing for novice grounded theorists. This article provides a worked example of the data analysis phase of a constructivist grounded theory study that examined family presence during resuscitation in acute health care settings. Core grounded theory methods are exemplified, including initial and focused coding, constant comparative analysis, memo writing, theoretical sampling, and theoretical saturation. The article traces the construction of the core category "Conditional Permission" from initial and focused codes, subcategories, and properties, through to its position in the final substantive grounded theory.

Identification of novel mutations in X-linked retinitis pigmentosa families and implications for diagnostic testing

PubMed Central

Glaus, Esther; Lorenz, Birgit; Netzer, Christian; Li, Yün; Schambeck, Maria; Wittmer, Mariana; Feil, Silke; Kirschner-Schwabe, Renate; Rosenberg, Thomas; Cremers, Frans P.M.; Bergen, Arthur A.B.; Barthelmes, Daniel; Baraki, Husnia; Schmid, Fabian; Tanner, Gaby; Fleischhauer, Johannes; Orth, Ulrike; Becker, Christian; Wegscheider, Erika; Nürnberg, Gudrun; Nürnberg, Peter; Bolz, Hanno Jörn; Gal, Andreas; Berger, Wolfgang

2008-01-01

Purpose The goal of this study was to identify mutations in X-chromosomal genes associated with retinitis pigmentosa (RP) in patients from Germany, The Netherlands, Denmark, and Switzerland. Methods In addition to all coding exons of RP2, exons 1 through 15, 9a, ORF15, 15a and 15b of RPGR were screened for mutations. PCR products were amplified from genomic DNA extracted from blood samples and analyzed by direct sequencing. In one family with apparently dominant inheritance of RP, linkage analysis identified an interval on the X chromosome containing RPGR, and mutation screening revealed a pathogenic variant in this gene. Patients of this family were examined clinically and by X-inactivation studies. Results This study included 141 RP families with possible X-chromosomal inheritance. In total, we identified 46 families with pathogenic sequence alterations in RPGR and RP2, of which 17 mutations have not been described previously. Two of the novel mutations represent the most 3’-terminal pathogenic sequence variants in RPGR and RP2 reported to date. In exon ORF15 of RPGR, we found eight novel and 14 known mutations. All lead to a disruption of open reading frame. Of the families with suggested X-chromosomal inheritance, 35% showed mutations in ORF15. In addition, we found five novel mutations in other exons of RPGR and four in RP2. Deletions in ORF15 of RPGR were identified in three families in which female carriers showed variable manifestation of the phenotype. Furthermore, an ORF15 mutation was found in an RP patient who additionally carries a 6.4 kbp deletion downstream of the coding region of exon ORF15. We did not identify mutations in 39 sporadic male cases from Switzerland. Conclusions RPGR mutations were confirmed to be the most frequent cause of RP in families with an X-chromosomal inheritance pattern. We propose a screening strategy to provide molecular diagnostics in these families. PMID:18552978

Act No. 42/1988 instituting the Preliminary Title and First Book of the Civil Code, 27 October 1988.

PubMed

1988-01-01

This document contains major provisions of the Preliminary Title and First Book (dealing with persons and the family) of the Civil Code enacted by Rwanda in 1988. These include the portions of Part 1 (physical persons) which deal with personality, birth, identification of physical persons, legal names, residence and domicile, and proof of civil status. Included sections of Part 2 (the family) cover marriage, engagement, the conclusion of marriage (with sections devoted to general provisions, substantive conditions, obligations arising from marriage, and respective rights and duties of spouses), the annulment of marriages and the effects of an annulled marriage, the dissolution of marriage and separation (divorce for specific reasons, divorce by mutual consent, and the effects of divorce), kinship and filiation (the kinship of children born legitimately or in marriage; proof of legitimate filiation; and legitimization, recognition, and support of natural children), adoption, and parental authority (general provisions, the right of custody, legal administration, legal enjoyment, loss of parental authority). The only section of Part 3 contained herein relates to the duty of the customary family council.

Structural organization and classification of cytochrome P450 genes in flax (Linum usitatissimum L.).

PubMed

Babu, Peram Ravindra; Rao, Khareedu Venkateswara; Reddy, Vudem Dashavantha

2013-01-15

Flax CYPome analysis resulted in the identification of 334 putative cytochrome P450 (CYP450) genes in the cultivated flax genome. Classification of flax CYP450 genes based on the sequence similarity with Arabidopsis orthologs and CYP450 nomenclature, revealed 10 clans representing 44 families and 98 subfamilies. CYP80, CYP83, CYP92, CYP702, CYP705, CYP708, CYP728, CYP729, CYP733 and CYP736 families are absent in the flax genome. The subfamily members exhibited conserved sequences, length of exons and phasing of introns. Similarity search of the genomic resources of wild flax species Linum bienne with CYP450 coding sequences of the cultivated flax, revealed the presence of 127 CYP450 gene orthologs, indicating amplification of novel CYP450 genes in the cultivated flax. Seven families CYP73, 74, 75, 76, 77, 84 and 709, coding for enzymes associated with phenylpropanoid/fatty acid metabolism, showed extensive gene amplification in the flax. About 59% of the flax CYP450 genes were present in the EST libraries. Copyright © 2012 Elsevier B.V. All rights reserved.

Drawing Dynamical and Parameters Planes of Iterative Families and Methods

PubMed Central

Chicharro, Francisco I.

2013-01-01

The complex dynamical analysis of the parametric fourth-order Kim's iterative family is made on quadratic polynomials, showing the MATLAB codes generated to draw the fractal images necessary to complete the study. The parameter spaces associated with the free critical points have been analyzed, showing the stable (and unstable) regions where the selection of the parameter will provide us the excellent schemes (or dreadful ones). PMID:24376386

Parental Psychological Control and Autonomy Granting: Distinctions and Associations with Child and Family Functioning

PubMed Central

Kunz, Jennifer Hauser; Grych, John H.

2012-01-01

Objective This study utilized an observational coding scheme to identify parenting behavior reflecting psychological control and autonomy granting and examined relations between these parenting dimensions and indices of child and family functioning. Design A community sample of 90 preadolescents (aged 10.5 to 12 years) and both of their parents engaged in a triadic interaction that was coded for parental psychological control and autonomy granting. Participants also completed measures of child adjustment, interparental conflict, and triangulation. Results Factor analyses indicated that a two-factor model better fit the data than a one-factor model, suggesting that psychological control and autonomy granting are best conceptualized as independent but related constructs. Parental psychological control and autonomy granting exhibited some shared and some unique correlates with indices of child and family functioning. Hierarchical regressions revealed significant interactions between these dimensions, suggesting that the strength of some associations between parents’ use of psychological control and youth adjustment problems depends on the level of autonomy granting exhibited by the parent. Conclusions By examining psychological control and autonomy granting simultaneously as unique constructs, this study identifies patterns of psychological control and autonomy granting that undermine youth adjustment. Findings inform targeted intervention efforts for families of preadolescent youth. PMID:23418403

Beyond diagnoses: family medicine core themes in student reflective writing.

PubMed

Bradner, Melissa K; Crossman, Steven H; Gary, Judy; Vanderbilt, Allison A; VanderWielen, Lynn

2015-03-01

We share qualitative study results of third-year medical student writings during their family medicine clerkship utilizing a reflective writing exercise from 2005 and 2013. For this paper, 50 student writings were randomly selected from the 2005 cohort in addition to 50 student writings completed by the 2013 cohort. Deductive thematic analysis utilizing Atlas.ti software was completed utilizing the Future of Family Medicine core attributes of family physicians as the a priori coding template. Student writings actively reflect key attributes of family physicians as described by the Future of Family Medicine Report: a deep understanding of the dynamics of the whole person, a generative impact on patients' lives, a talent for humanizing the health care experience, and a natural command of complexity and multidimensional access to care. We discuss how to lead the writing exercise and provide suggestions for facilitating the discussion to bring out these important aspects of family medicine care.

40 CFR 86.000-24 - Test vehicles and engines.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-Duty Engines, and for 1985 and Later Model Year New Gasoline Fueled, Natural Gas-Fueled, Liquefied... family, the Administrator will limit selections to engine codes which have air conditioning available and...

Critical Care Nurses' Experiences With Spiritual Care: The SPIRIT Study.

PubMed

Bone, Nigel; Swinton, Marilyn; Hoad, Neala; Toledo, Feli; Cook, Deborah

2018-05-01

Little is known about the effect of chaplains on critical care nurses who are caring for critically ill patients and their families. To understand nurses' experiences when they make a referral to the Spiritual Care Department for a patient or the family of a patient who is dying or deceased. Specific aims were to explore spiritual care's effect on nurses and how nurses understand the role of spiritual care in practice. A qualitative descriptive study using in-person, semistructured interviews in a 21-bed medical-surgical intensive care unit in a teaching hospital. Purposeful sampling identified nurses who had at least 5 years of experience and had cared for at least 5 patients who died on their shift and at least 5 patients for whom they initiated a spiritual care referral. Interviews were digitally recorded and anonymized; conventional content analysis was used to analyze transcripts. Three investigators independently coded 5 transcripts and developed the preliminary coding list. As analysis proceeded, investigators organized codes into categories and themes. A total of 25 nurses were interviewed. The central theme that emerged was presence, described through 3 main categories: the value of having chaplains present in the intensive care unit and their role, nurses' experiences working with chaplains, and nurses' experiences providing spiritual care. Nurses considered spiritual care essential to holistic care and valued the support chaplains provide to patients, families, and staff in today's spiritually diverse society. © 2018 American Association of Critical-Care Nurses.

Barriers Against Implementing Blunt Abdominal Trauma Guidelines in a Hospital: A Qualitative Study

PubMed Central

Zaboli, Rouhollah; Tofighi, Shahram; Aghighi, Ali; Shokouh, Seyyed Javad Hosaini; Naraghi, Nader; Goodarzi, Hassan

2016-01-01

Introduction Clinical practice guidelines are structured recommendations that help physicians and patients to make proper decisions when dealing with a specific clinical condition. Because blunt abdominal trauma causes a various range of mild, single-system, and multisystem injuries, early detection will help to reduce mortality and resulting disability. Emergency treatment should be initiated based on CPGs. This study aimed to determine the variables affecting implementing blunt abdominal trauma CPGs in an Iranian hospital. Methods This study was conducted as a qualitative and phenomenology study in the Family Hospital in Tehran (Iran) in 2015. The research population included eight experts and key people in the area of blunt abdominal trauma clinical practice guidelines. Sampling was based on purposive and nonrandom methods. A semistructured interview was done for the data collection. A framework method was applied for the data analysis by using Atlas.ti software. Results After framework analyzing and various reviewing and deleting and combining the codes from 251 codes obtained, 15 families and five super families were extracted, including technical knowledge barriers, economical barriers, barriers related to deployment and monitoring, political will barriers, and managing barriers. Conclusion Structural reform is needed for eliminating the defects available in the healthcare system. As with most of the codes, subconcepts and concepts are classified into the field of human resources; it seems that the education and knowledge will be more important than other resources such as capital and equipment. PMID:27757191

Comparative Mitogenomics of Plant Bugs (Hemiptera: Miridae): Identifying the AGG Codon Reassignments between Serine and Lysine

PubMed Central

Wang, Pei; Song, Fan; Cai, Wanzhi

2014-01-01

Insect mitochondrial genomes are very important to understand the molecular evolution as well as for phylogenetic and phylogeographic studies of the insects. The Miridae are the largest family of Heteroptera encompassing more than 11,000 described species and of great economic importance. For better understanding the diversity and the evolution of plant bugs, we sequence five new mitochondrial genomes and present the first comparative analysis of nine mitochondrial genomes of mirids available to date. Our result showed that gene content, gene arrangement, base composition and sequences of mitochondrial transcription termination factor were conserved in plant bugs. Intra-genus species shared more conserved genomic characteristics, such as nucleotide and amino acid composition of protein-coding genes, secondary structure and anticodon mutations of tRNAs, and non-coding sequences. Control region possessed several distinct characteristics, including: variable size, abundant tandem repetitions, and intra-genus conservation; and was useful in evolutionary and population genetic studies. The AGG codon reassignments were investigated between serine and lysine in the genera Adelphocoris and other cimicomorphans. Our analysis revealed correlated evolution between reassignments of the AGG codon and specific point mutations at the antidocons of tRNALys and tRNASer(AGN). Phylogenetic analysis indicated that mitochondrial genome sequences were useful in resolving family level relationship of Cimicomorpha. Comparative evolutionary analysis of plant bug mitochondrial genomes allowed the identification of previously neglected coding genes or non-coding regions as potential molecular markers. The finding of the AGG codon reassignments between serine and lysine indicated the parallel evolution of the genetic code in Hemiptera mitochondrial genomes. PMID:24988409

Development, dissemination, and applications of a new terminological resource, the Q-Code taxonomy for professional aspects of general practice/family medicine.

PubMed

Jamoulle, Marc; Resnick, Melissa; Grosjean, Julien; Ittoo, Ashwin; Cardillo, Elena; Vander Stichele, Robert; Darmoni, Stefan; Vanmeerbeek, Marc

2018-12-01

While documentation of clinical aspects of General Practice/Family Medicine (GP/FM) is assured by the International Classification of Primary Care (ICPC), there is no taxonomy for the professional aspects (context and management) of GP/FM. To present the development, dissemination, applications, and resulting face validity of the Q-Codes taxonomy specifically designed to describe contextual features of GP/FM, proposed as an extension to the ICPC. The Q-Codes taxonomy was developed from Lamberts' seminal idea for indexing contextual content (1987) by a multi-disciplinary team of knowledge engineers, linguists and general practitioners, through a qualitative and iterative analysis of 1702 abstracts from six GP/FM conferences using Atlas.ti software. A total of 182 concepts, called Q-Codes, representing professional aspects of GP/FM were identified and organized in a taxonomy. Dissemination: The taxonomy is published as an online terminological resource, using semantic web techniques and web ontology language (OWL) ( http://www.hetop.eu/Q ). Each Q-Code is identified with a unique resource identifier (URI), and provided with preferred terms, and scope notes in ten languages (Portuguese, Spanish, English, French, Dutch, Korean, Vietnamese, Turkish, Georgian, German) and search filters for MEDLINE and web searches. This taxonomy has already been used to support queries in bibliographic databases (e.g., MEDLINE), to facilitate indexing of grey literature in GP/FM as congress abstracts, master theses, websites and as an educational tool in vocational teaching, Conclusions: The rapidly growing list of practical applications provides face-validity for the usefulness of this freely available new terminological resource.

The complete mitogenome of the river blackfish, Gadopsis marmoratus (Richardson, 1848) (Teleostei: Percichthyidae).

PubMed

Gan, Han Ming; Tan, Mun Hua; Lee, Yin Peng; Austin, Christopher M

2016-05-01

The mitogenome of the Australian freshwater blackfish, Gadopsis marmoratus was recovered coverage by genome skimming using the MiSeq sequencer (GenBank Accession Number: NC_024436). The blackfish mitogenome has 16,407 base pairs made up of 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a 819 bp non-coding AT-rich region. This is the 5th mitogenome sequence to be reported for the family Percichthyidae.

The RealGas and RealGasH2O options of the TOUGH+ code for the simulation of coupled fluid and heat flow in tight/shale gas systems

EPA Science Inventory

We developed two new EOS additions to the TOUGH+ family of codes, the RealGasH2O and RealGas. The RealGasH2O EOS option describes the non-isothermal two-phase flow of water and a real gas mixture in gas reservoirs, with a particular focus in ultra-tight (such as tight-sand and sh...

Complete genome sequence of Sanguibacter keddieii type strain (ST-74T)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivanova, Natalia; Sikorski, Johannes; Sims, David

2009-05-20

Sanguibacter keddieii is the type species of the genus Sanguibacter, the only described genus within the family of Sanguibacteraceae. Phylogenetically, this family is located in the neighbourhood of the genus Oerskovia and the family Cellulomonadaceae within the actinobacterial suborder Micrococcineae. The strain described in this report was isolated from blood of apparently healthy cows. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the family Sanguibacteraceae, and the 4,253,413 bp long single replicon genome with its 3735 protein-coding and 70 RNA genes is part ofmore » the Genomic Encyclopedia of Bacteria and Archaea project.« less

Exploring families' experiences of health: contributions to a model of family health.

PubMed

Smith, Sarah L; DeGrace, Beth; Ciro, Carrie; Bax, Ami; Hambrick, Andrea; James, Jennifer; Evans, Alexandra

2017-12-01

Child health and developmental outcomes are influenced by the health of the family and the context created. Research suggests symptoms of poor family health (e.g. suboptimal family interactions, parenting stress) yet there is limited understanding of the factors which contribute to robust family health which may unveil opportunities for targeted intervention and family health promotion. The present study examined families' experiences of family health and factors contributing to family health. We performed a qualitative study using constructivist grounded theory methods to guide our understanding of family health for families with typically developing children aged 5-18. Interviews were conducted in family homes and all members were invited to participate. Data from interviews were transcribed, coded, thematically analyzed, and verified with select families. Ten families, including 10 mothers, 8 fathers, and 15 children participated in the study. Participants described family health as a process of balance, living purposefully, and sharing experiences together in alignment with family identity. Mediating family health were processes of awareness and reflection, and adapting, adjusting, and changing in response to family life including external stress factors. Results highlight the possibility for healthcare practitioners to facilitate families' self-reflection and awareness about their health in order to mediate family health development.

DataRocket: Interactive Visualisation of Data Structures

NASA Astrophysics Data System (ADS)

Parkes, Steve; Ramsay, Craig

2010-08-01

CodeRocket is a software engineering tool that provides cognitive support to the software engineer for reasoning about a method or procedure and for documenting the resulting code [1]. DataRocket is a software engineering tool designed to support visualisation and reasoning about program data structures. DataRocket is part of the CodeRocket family of software tools developed by Rapid Quality Systems [2] a spin-out company from the Space Technology Centre at the University of Dundee. CodeRocket and DataRocket integrate seamlessly with existing architectural design and coding tools and provide extensive documentation with little or no effort on behalf of the software engineer. Comprehensive, abstract, detailed design documentation is available early on in a project so that it can be used for design reviews with project managers and non expert stakeholders. Code and documentation remain fully synchronised even when changes are implemented in the code without reference to the existing documentation. At the end of a project the press of a button suffices to produce the detailed design document. Existing legacy code can be easily imported into CodeRocket and DataRocket to reverse engineer detailed design documentation making legacy code more manageable and adding substantially to its value. This paper introduces CodeRocket. It then explains the rationale for DataRocket and describes the key features of this new tool. Finally the major benefits of DataRocket for different stakeholders are considered.

Changing Utilization of Noninvasive Diagnostic Imaging Over 2 Decades: An Examination Family-Focused Analysis of Medicare Claims Using the Neiman Imaging Types of Service Categorization System.

PubMed

Rosman, David A; Duszak, Richard; Wang, Wenyi; Hughes, Danny R; Rosenkrantz, Andrew B

2018-02-01

The objective of our study was to use a new modality and body region categorization system to assess changing utilization of noninvasive diagnostic imaging in the Medicare fee-for-service population over a recent 20-year period (1994-2013). All Medicare Part B Physician Fee Schedule services billed between 1994 and 2013 were identified using Physician/Supplier Procedure Summary master files. Billed codes for diagnostic imaging were classified using the Neiman Imaging Types of Service (NITOS) coding system by both modality and body region. Utilization rates per 1000 beneficiaries were calculated for families of services. Among all diagnostic imaging modalities, growth was greatest for MRI (+312%) and CT (+151%) and was lower for ultrasound, nuclear medicine, and radiography and fluoroscopy (range, +1% to +31%). Among body regions, service growth was greatest for brain (+126%) and spine (+74%) imaging; showed milder growth (range, +18% to +67%) for imaging of the head and neck, breast, abdomen and pelvis, and extremity; and showed slight declines (range, -2% to -7%) for cardiac and chest imaging overall. The following specific imaging service families showed massive (> +100%) growth: cardiac CT, cardiac MRI, and breast MRI. NITOS categorization permits identification of temporal shifts in noninvasive diagnostic imaging by specific modality- and region-focused families, providing a granular understanding and reproducible analysis of global changes in imaging overall. Service family-level perspectives may help inform ongoing policy efforts to optimize imaging utilization and appropriateness.