Tandem system adaptation using multiple linear feature transforms

Adaptation to speaker and environment changes is an essential part of current automatic speech recognition (ASR) systems. In recent years the use of multi-layer percpetrons (MLPs) has become increasingly common in ASR systems. A standard approach to handling speaker differences when using MLPs is to apply a global speaker-specific constrained MLLR (CMLLR) transform to the features prior to training or using the MLP. This paper considers the situation when there are both speaker and channel, communication link, differences in the data. A more powerful transform, front-end CMLLR (FE-CMLLR), is applied to the inputs to the MLP to represent the channel differences. Though global, these FE-CMLLR transforms vary from time-instance to time-instance. Experiments on a channel distorted dialect Arabic conversational speech recognition task indicates the usefulness of adapting MLP features using both CMLLR and FE-CMLLR transforms. © 2013 IEEE.

Analysis of heavy metals of muscle and intestine tissue in fish - in Banan section of Chongqing from Three Gorges Reservoir, China

The present study was carried out to investigate contamination of heavy metals in 19 fish species from the Banan section of Chongqing in the Three Gorges, Yangtze River. The results showed that the mean concentrations of heavy metals were higher in intestine than muscle, except zinc in upper strata. In the fish inhabiting the upper strata, there were significant differences between mean concentrations of As, Cr, Cu and Hg in muscle and intestine (P <0.05). There were also significant differences between mean concentrations of Cr and Cu in muscle and intestine in the fish inhabiting middle strata. However, significant differences between mean concentrations of As, Cd, Hg, Pb and Zn were measured in fish inhabiting bottom strata in both intestine and muscle tissues (P <0.05). For the fish inhabiting different strata, the concentrations of As, Cd, Cr, Cu, Hg and Ph in muscle and intestine of the fish from bottom strata (BS) were higher than those in both upper strata (US) and middle strata (MS); whereas a higher concentration of Zn was measured in muscle and intestine from fish inhabiting upper strata. Mean metal concentrations were found to be higher in age 11 than those in age I in Coreius heterodon (2- and 1-year odl fish respectively). The overall results indicated that fish muscle in the Banan section were slightly contaminated by heavy metals, but did not exceed Chinese food standards.

Changes in biomechanical properties of the coronary artery wall contribute to maintained contractile responses to endothelin-1 in atherosclerosis.

AIMS: Our aim was to determine whether alterations in biomechanical properties of human diseased compared to normal coronary artery contribute to changes in artery responsiveness to endothelin-1 in atherosclerosis. MAIN METHODS: Concentration-response curves were constructed to endothelin-1 in normal and diseased coronary artery. The passive mechanical properties of arteries were determined using tensile ring tests from which finite element models of passive mechanical properties of both groups were created. Finite element modelling of artery endothelin-1 responses was then performed. KEY FINDINGS: Maximum responses to endothelin-1 were significantly attenuated in diseased (27±3 mN, n=55) compared to normal (38±2 mN, n=68) artery, although this remained over 70% of control. There was no difference in potency (pD2 control=8.03±0.06; pD2 diseased=7.98±0.06). Finite element modelling of tensile ring tests resulted in hyperelastic shear modulus μ=2004±410 Pa and hardening exponent α=22.8±2.2 for normal wall and μ=2464±1075 Pa and α=38.3±6.7 for plaque tissue and distensibility of diseased vessels was decreased. Finite element modelling of active properties of both groups resulted in higher muscle contractile strain (represented by thermal reactivity) of the atherosclerotic artery model than the normal artery model. The models suggest that a change in muscle response to endothelin-1 occurs in atherosclerotic artery to increase its distensibility towards that seen in normal artery. SIGNIFICANCE: Our data suggest that an adaptation occurs in medial smooth muscle of atherosclerotic coronary artery to maintain distensibility of the vessel wall in the presence of endothelin-1. This may contribute to the vasospastic effect of locally increased endothelin-1 production that is reported in this condition.

Effect of a feeding stimulant on feeding adaptation of gibel carp Carassius auratus gibelio (Bloch), fed diets with replacement of fish meal by meat and bone meal

The objectives of the study were to investigate the effect of a feeding stimulant on feeding adaptation of gibel carp (Carassius auratus gibelio Bloch) fed diets with replacement of fish meal by meat and bone meal (MBM), and whether or not the juvenile gibel carp could adapt to higher MBM level in the diet. Juvenile and adult gibel carp were tested. Two and one replacement levels were used for juvenile and adult fish respectively. Each group of diets was set as two types with or without a unique rare earth oxide: Y2O3, Yb2O3, La2O3, Sm2O3, Nd2O3 or Gd2O3 (only the first four rare earth oxides were used in adult diets) for four adaptation periods of 3, 7, 14 and 28 days respectively. After mixing, an equal mixture of all six diets for juvenile or four diets for adult was offered in excess for 2 days. During the last 2 days of each experiment, no feed was offered and faeces from each tank were collected. Feeding preference was expressed as relative feed intake of each diet, which was estimated based on the relative concentration of each marker in the faeces. Given some adaptation period, such as 3-28 days, the effects of MBM and squid extract inclusion on the preference to each diet were reduced. After 28 days adaptation, the preferences between groups were not significantly different.

Myxobolus lentisuturalis sp n. (Myxozoa : Myxobolidae), a new muscle-infecting species from the Prussian carp, Carassius gibelio from China

A new highly pathogenic muscle-infecting species of the genus Myxobolus Butschli, 1882 is described from the Prussian carp, Carassius gibelio (Bloch, 1782) using spore morphology and SSU rDNA sequence data. Phylogenetic analyses elucidated relationship of the newly described Myxobolus lentisuturalis to other Myxobolus species and supported its position of an independent species.

Independent adaptation to riverine habitats allowed survival of ancient cetacean lineages

The four species of "river dolphins" are associated with six separate great river systems on three subcontinents and have been grouped for more than a century into a single taxon based on their similar appearance. However, several morphologists recently questioned the monophyly of that group. By using phylogenetic analyses of nucleotide sequences from three mitochondrial and two nuclear genes, we demonstrate with statistical significance that extant river dolphins are not monophyletic and suggest that they are relict species whose adaptation to riverine habitats incidentally insured their survival against major environmental changes in the marine ecosystem or the emergence of Delphinidae.

A VSLMS Style Tap-length Learning Algorithm for Structure Adaptation

Compared with the ordinary adaptive filter, the variable-length adaptive filter is more efficient (including smaller., lower power consumption and higher computational complexity output SNR) because of its tap-length learning algorithm, which is able to dynamically adapt its tap-length to the optimal tap-length that best balances the complexity and the performance of the adaptive filter. Among existing tap-length algorithms, the LMS-style Variable Tap-Length Algorithm (also called Fractional Tap-Length Algorithm or FT Algorithm) proposed by Y.Gong has the best performance because it has the fastest convergence rates and best stability. However, in some cases its performance deteriorates dramatically. To solve this problem, we first analyze the FT algorithm and point out some of its defects. Second, we propose a new FT algorithm called 'VSLMS' (Variable Step-size LMS) Style Tap-Length Learning Algorithm, which not only uses the concept of FT but also introduces a new concept of adaptive convergence slope. With this improvement the new FT algorithm has even faster convergence rates and better stability. Finally, we offer computer simulations to verify this improvement.

Kinetic spectra of light-adaptation dark-adaptation and M-intermediate of BR-D96N

BR-D96N is a kind of genetically site-specific mutants of bacteriorhodopsin (BR) with obvious photochromic effect. Compared to the wild type BR, the lifetime of M state of BR-D96N is prolonged to several minutes so that the photochromic kinetics and the intermediates formation can be studied by the conventional spectra analysis. In the experiment, the absorption spectra of the sample at different time after light illumination are measured with spectrophotometer. By fitting and analyzing the variation of the spectra, we suppose that there are three main states in the, photochromic process, i.e., B state (light-adapted state), M state and D state (dark-adapted state). The absorption spectra of the B state, M state and D state are extracted from the experimental data based on this three-state model and the spectra at various time are fitted with the least-square method. So, the variations of population percentages of the M state, B state and D state are obtained and the M state and B state lifetimes are estimated. In another way, from the measurement of the absorption dynamics at 407 and 568 nm, the M state and B state lifetimes are also obtained by two exponential data fitting, which give coincident results with those of the spectra analysis. (C) 2003 Elsevier Science B.V. All rights reserved.

Purification and partial characterization of Mn superoxide dismutase from muscle tissue of the shrimp Macrobrachium nipponense

Superoxide dismutase (SOD; EC 1.15.1.1) is an enzyme that protects against oxidative stress from superoxide radicals in living cells. This enzyme had been isolated, purified and partially characterized from muscle tissue of the shrimp Macrobrachium nipponense. The purification was achieved by heat treatment, ammonium sulfate fractionated precipitation and column chromatograph on DEAE-cellulose 32. Some physiological and biochemical characterization of it was tested. The molecular weight of it was about 21.7 kDa, as judged by SDS-polyacrylamide gel electrophoresis. The purified enzyme had an absorption peak of 278 nm in ultraviolet region, and the enzyme remained stable at 25-45 degreesC within 90 min. However, it was rapidly inactivated at higher temperature. Treatment of the enzyme with 1 mM ZnCl2, SDS and 1 mM or 10 mM mercaptoethanol showed some increasing activity. However, the enzyme activity was obviously inhibited by 10 mM CaCl2, CuSO4, ZnCl2 and 1 mM CaCl2 and 10 mM K2Cr2O7. SOD activity did not show significantly variation after incubated with 1 mM CaCl2, EDTA and 10 MM SDS. The enzyme was insensitive to cyanide and contained 1.03 +/- 0.14 atoms of manganese per subunit shown in atomic absorption spectroscopy, which revealed that purified SOD was Mn superoxide dismutase. (C) 2004 Elsevier B.V. All rights reserved.

Expression of muscle-related genes and two MyoD genes during amphioxus notochord development

The notochord is one of the diagnostic features of the phylum Chordata. Despite the similarities in the early morphogenetic patterns of the notochords of various chordates, they are strikingly distinct from one another at the histological level. The amphioxus notochord is one example of an evolutionary novelty because it is made up of muscle cells. Our previous expressed sequence tag analysis, targeting messenger RNAs expressed in the adult amphioxus notochord, demonstrated that many muscle-related genes are expressed there. To characterize amphioxus notochord cells and to gain insights into the myogenic program in the notochord, we determined the spatial and temporal expression patterns of these muscle-related genes during amphioxus development. We found that BbNA1 (notochord actin), Amphi-Trop I (troponin I), Amphi-TPmyosin (tropomyosin), Amphi-MHC2 (myosin heavy chain), Amphi-nMRLC (notochord-specific myosin regulatory light chain), AmphinTitin/MLCK (notochord-specific titin/myosin light chain kinase), Amphi-MLP/CRP3 (muscle LIM protein), and Amphi-nCalponin (notochord-specific calponin) are expressed with characteristic patterns in notochord cells, including the central cells, dorsally located cells, and ventrally located cells, suggesting that each notochord cell has a unique molecular architecture that may reflect its function. In addition, we characterized two MyoD genes (Amphi-MyoD1 and Amphi-MyoD2) to gain insight into the genetic circuitry governing the formation of the notochord muscle. One of the MyoD genes (Amphi-MyoD2) is expressed in the central notochord cells, and the coexistence of Amphi-MyoD2 transcripts along with the Amphi-MLP/CRP3 transcripts implies the participation of Amphi-MyoD2 in the myogenic program in the notochord muscle.

Cloning and expression analysis of myogenin from flounder (Paralichthys olivaceus) and promoter analysis of muscle-specific expression

Myogenin is a bHLH transcription factor of the MyoD family. It plays a crucial role in myoblast differentiation and maturation. We report here the isolation of flounder myogenin gene and the characterization of its expression patterns. Sequence analysis indicated that flounder myogenin shared a similar structure and the conserved bHLH domain with other vertebrate myogenin genes. Flounder myogenin gene contains 3 exons and 2 introns. Sequence alignment and phylogenetic showed that flounder myogenin was more homologous with halibut (Hippoglossus hippoglossus) myogenin and striped bass (Morone saxatilis) myogenin. Whole-mount embryo in situ hybridization revealed that flounder myogenin was first detected in the medial region of somites that give rise to slow muscles, and expanded later to the lateral region of the somite that become fast muscles. The levels of myogenin transcripts dropped significantly in matured somites at the trunk region. Its expression could only be detected in the caudal somites, which was consistent with the timing of somite maturation. Transient expression analysis showed that the 546 bp flounder myogenin promoter was sufficient to direct muscle-specific GFP expression in zebrafish embryos. (c) 2007 Elsevier Inc. All rights reserved.

Characterization of muscle-regulatory gene, MyoD, from flounder (Paralichthys olivaceus) and analysis of its expression patterns during embryogenesis

Specification and differentiation of skeletal muscle cells are driven by the activity of genes encoding members of the myogenic regulatory factors (MRFs). In vertebrates, the MRF family includes MyoD, Myf5, myogenin, and MRF4. The MRFs are capable of converting a variety of nonmuscle cells into myoblasts and myotubes. To better understand their roles in fish muscle development, we isolated the MyoD gene from flounder (Paralichthys olivaceus) and analyzed its structure and patterns of expression. Sequence analysis showed that flounder MyoD shared a structure similar to that of vertebrate MRFs with three exons and two introns, and its protein contained a highly conserved basic helix-loop-helix domain (bHLH). Comparison of sequences revealed that flounder MyoD was highly conserved with other fish MyoD genes. Sequence alignment and phylogenetic analysis indicated that flounder MyoD, seabream (Sparus aurata) MyoD1, takifugu (Takifugu rubripes) MyoD, and tilapia (Oreochromis aureus) MyoD were more likely to be homologous genes. Flounder MyoD expression was first detected as two rows of presomitic cells in the segmental plate. From somitogenesis, MyoD transcripts were present in the adaxial cells that give rise to slow muscles and the lateral somitic cells that give rise to fast muscles. After 30 somites formed, MyoD expression decreased in the somites except the caudal somites, coincident with somite maturation. In the hatching stage, MyoD was expressed in other muscle cells and caudal somites. It was detected only in muscle in the growing fish.

Cloning of hypoxia-inducible factor 1 alpha cDNA from a high hypoxia tolerant mammal - plateau pika (Ochotona curzoniae)

Hypoxia-inducible factor I is a transcription factor composed of HIF-1alpha and HIF-1beta. It plays an important role in the signal transduction of cell response to hypoxia. Plateau pika (Ochotona curzoniae) is a high hypoxia-tolerant and cold adaptation species livin only at 3000-5000m above sea level on the Qinghai-Tibet Plateau. In this study, HIF-1alpha cDNA of plateau pika was cloned and its expression in various tissues was studied. The results indicated that plateau pika HIF-1alpha cDNA was highly identical to those of the human (82%), bovine (89%), mouse (82%), and Norway rat (77%). The deduced amino acid sequence (822 bp) showed 90%, 92%, 86%, and 86% identities with those of the human, bovine, house mouse, and Norway rat, respectively. Northern blot analyses detected two isoforms named pLHIF-1alpha and pSHIF-1alpha. The HIF-1alpha mRNA was highly expressed in the brain and kidney, and much less in the heart, lung, liver, muscle, and spleen, which was quite different from the expression pattern of mouse mRNA. Meanwhile, a new variant of plateau pika HIF-1alpha mRNA was identified by RT-PCR and characterized. The deduced protein, composed of 536 amino acids, lacks a part of the oxygen-dependent degradation domain (ODD), both transactivation domains (TADs), and the nuclear localization signal motif (NLS). Our results suggest that HIF-1alpha may play an important role in the pika's adaptation to hypoxia, especially in brain and kidney, and pika HIF-1alpha function pattern may be different from that of mouse HIF-1alpha. Further-more, for the high ratio of HIF-1alpha homology among the animals, the HIF-1alpha gene may be a good phylogenetic performer in recovering the true phylogenetic relationships among taxa. (C) 2004 Elsevier Inc. All rights reserved.