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•What is the primary question addressed by this study?Are there causes of reduced DAT-SPECT accumulation in the striatum of depressed patients other than from known neurodegenerative diseases?•What is the main finding of this study?Five female patients with depressive symptoms and aging-related catatonia showed recovery of initially reduced striatal DAT-SPECT accumulation following psychiatric treatment.•What is the meaning of the finding?The findings suggest that impairment of dopaminergic transmission partly underlies catatonia, and that it is associated with a reversible decrease in striatal DAT-SPECT accumulation.

Despite some efforts and attempts have been made to improve the direction-of-arrival (DOA) estimation performance of the standard Capon beamformer (SCB) in array processing, rigorous statistical performance analyses of these modified Capon estimators are still lacking. This paper studies an improved Capon estimator (ICE) for estimating the DOAs of multiple uncorrelated narrowband signals, where the higher-order inverse (sample) array covariance matrix is used in the Capon-like cost function. By establishing the relationship between this nonparametric estimator and the parametric and classic subspace-based MUSIC (multiple signal classification), it is clarified that as long as the power order of the inverse covariance matrix is increased to reduce the influence of signal subspace components in the ICE, the estimation performance of the ICE becomes equivalent to that of the MUSIC regardless of the signal-to-noise ratio (SNR). Furthermore the statistical performance of the ICE is analyzed, and the large-sample mean-squared-error (MSE) expression of the estimated DOA is derived. Finally the effectiveness and the theoretical analysis of the ICE are substantiated through numerical examples, where the Cramer-Rao lower bound (CRB) is used to evaluate the validity of the derived asymptotic MSE expression.

System identification suffers from severe numerical problems when the experimental data do not contain sufficient independent information on system dynamics, or they are contaminated by complicated noises. As a result, numerical optimization used in identification cannot guarantee the global optimal solutions, thus most of the existing identification algorithms have poor global convergence performance unless strong external test signals are available. In this paper, a new identification algorithm based on multi-individual optimization is investigated to improve its convergence performance under severe numerical conditions. It is illustrated that some distinctive information can be extracted from the experimental data collected by output over-sampling scheme, and can complement information criterion for numerical optimization. Furthermore, the multi-individual scheme is utilized to decrease the influence of initial conditions and local minima. The numerical simulation examples illustrate that the convergence performance has been improved in the proposed algorithm.

The importance of epigenetic control in the development of the central nervous system has recently been attracting attention. Methylation patterns of lysine 4 and lysine 36 in histone H3 (H3K4 and H3K36) in the central nervous system are highly conserved among species. Numerous complications of body malformations and neuropsychiatric disorders are due to abnormal histone H3 methylation modifiers. In this study, we analyzed a Japanese family with a dominant inheritance of symptoms including Marfan syndrome-like minor physical anomalies (MPAs), intellectual disability, and schizophrenia (SCZ). We performed positional cloning for this family using a single nucleotide polymorphism (SNP) array and whole-exome sequencing, which revealed a missense coding strand mutation (rs1555289644, NM_032590.4: c.2173G>A, p.A725T) in exon 15 on the plant homeodomain of the KDM2Bgene as a possible cause of the disease in the family. The exome sequencing revealed that within the coding region, only a point mutation in KDM2Bwas present in the region with the highest logarithm of odds score of 2.41 resulting from whole genome linkage analysis. Haplotype analysis revealed co-segregation with four affected family members (IV-9, III-4, IV-5, and IV-8). Lymphoblastoid cell lines from the proband with this mutation showed approximately halved KDM2Bexpression in comparison with healthy controls. KDM2B acts as an H3K4 and H3K36 histone demethylase. Our findings suggest that haploinsufficiency of KDM2Bin the process of development, like other H3K4 and H3K36 methylation modifiers, may have caused MPAs, intellectual disability, and SCZ in this Japanese family.

Benign adult familial myoclonic epilepsy (BAFME) is an autosomal dominant disease characterized by adult-onset tremulous hand movement, myoclonus, and infrequent epileptic seizures. Recently, intronic expansion of unstable TTTCA/TTTTA pentanucleotide repeats in SAMD12, TNRC6A, or RAPGEF2was identified as pathological mutations in Japanese BAFME pedigrees. To confirm these mutations, we performed a genetic analysis on 12 Japanese BAFME pedigrees. A total of 143 participants, including 43 familial patients, 5 suspected patients, 3 sporadic nonfamilial patients, 22 unaffected familial members, and 70 unrelated controls, were screened for expanded abnormal pentanucleotide repeats in SAMD12, TNRC6A, RAPGEF2, YEAT2, MARCH6, and STARD7. DNA samples were analyzed using Southern blotting, long-range polymerase chain reaction (PCR), repeat-primed PCR, and long-range PCR followed by Southern blotting. Of the 51 individuals with clinically diagnosed or suspected BAFME, 49 carried a SAMD12allele with an expanded TTTCA/TTTTA pentanucleotide repeat. Genetic and clinical anticipation was observed. As in previous reports, the one patient with homozygous mutant alleles showed more severe symptoms than the heterozygous carriers. In addition, screening for expanded pentanucleotide repeats in TNRC6Arevealed that the frequency of expanded TTTTA repeat alleles in the BAFME group was significantly higher than in the control group. All patients who were clinically diagnosed with BAFME, including those in the original family reported by Yasuda, carried abnormally expanded TTTCA/TTTTA repeat alleles of SAMD12. Patients with BAFME also frequently carried a TTTTA repeat expansion in TNRC6A, suggesting that there may be unknown factors in the ancestry of patients with BAFME that make pentanucleotide repeats unstable.

Bipolar disorder (BD) is a severe psychiatric disorder characterized by the recurrence of depressive and manic episodes. Its heritability is high, and many linkage and association studies have been performed. Although various linkage regions and candidate genes have been reported, few have shown sufficient reproducibility, and none have identified the pathogenic genes based on the results of the linkage analysis. To find functional variants that are expected to be rare and have strong genetic effects, we recruited ten healthy individuals, two individuals with unknown status, and six patients with BD or recurrent major depressive disorder (MDD) from a Japanese family consisting of 21 members. We performed a genome-wide linkage analysis using a 100K single-nucleotide polymorphism (SNP) array and microsatellite markers to narrow linkage regions within this family. Subsequently, we performed whole-exome sequencing for two patients with BD to identify genetic mutations in the narrowed linkage regions. Then, we performed co-segregation analysis for DNA variants obtained from the results of the exome sequencing. Finally, we identified a rare heterozygous mutation in exon 31 of DOCK5(c.3170A>G, p.E1057G). Convergent functional genomics analysis revealed that DOCK5was listed as one of the biomarkers for mood state and suicidality. Although DOCK5is still a functionally unknown gene, our findings highlight the possibility of a pathological relationship between BD and DOCK5.

The surface structure of copper (Cu) electrodes is a key factor determining product selectivity during electrochemical reduction reaction of carbon dioxide (CO2ERR). We investigated the influence of the chemical etchant on the Cu surface morphology as well as the product selectivity by CO2ERR. The hydrocarbon selectivity in CO2ERR was strongly dependent on the chemical etchant. Moreover, the construction of Cu surface for enhanced ethylene (C2H4) formation was also achieved by chemical etching treatment.The surface structure of copper (Cu) electrodes is a key factor determining product selectivity during electrochemical reduction reaction of carbon dioxide (CO2ERR). We investigated the influence of the chemical etchant on the Cu surface morphology as well as the product selectivity by CO2ERR. The hydrocarbon selectivity in CO2ERR was strongly dependent on the chemical etchant. Moreover, the construction of Cu surface for enhanced ethylene (C2H4) formation was also achieved by chemical etching treatment.

It is necessary to perform the system identification under severe numerical conditions in many practical applications. When less external test signals are available for parameter estimation from experimental data, the identification performance often suffers from numerical problems in the optimization procedure due to the less independent informative components, the influence of complicated noise, or the local minima problem. In this paper, a multi-point search based identification algorithm is investigated for system identification under severe numerical conditions. It introduces the output over-sampling scheme to collect the experimental input-output data, and extracts the information in time and space domains to complement information criterion for numerical optimization. Furthermore, the multi-point search is utilized to decrease the influence of local minima. The numerical simulation examples illustrate that the identification performance has been improved in the proposed algorithm.

Objective: The pathophysiology of neuroleptic malignant syndrome is mainly explained by a central hypodopaminergic state. The familial occurrence of neuroleptic malignant syndrome suggests the involvement of a genetic mechanism in the predisposition to the syndrome. Therefore, the authors examined the association between the Taql A polymorphism of the dopamine D2 receptor gene ([DRD.sub.2]), which alters [DRD.sub.2] density and function, and the development of neuroleptic malignant syndrome. Method: The subjects were 15 psychiatric patients who had developed neuroleptic malignant syndrome (12 patients with schizophrenia and three with major depression) and 138 patients with schizophrenia who had never developed neuroleptic malignant syndrome. The Taql A genotypes, A1 and A2 alleles, were determined by the polymerase chain reaction method. Results: The frequency of the A1 allele was significantly higher in the patients who had developed neuroleptic malignant syndrome (56.8%) than in the patients who had not (35.1%). The proportion of the A1 carrier was significantly higher in the patients with neuroleptic malignant syndrome (14 [93.3%] of 15 patients) than in those without the syndrome (79 [57.2%] of 138 patients). Conclusions: These findings suggest that the Taql A [DRD.sub.2] polymorphism is associated with the predisposition to neuroleptic malignant syndrome. (Am J Psychiatry 2001; 158:1714-1716)

Epilepsy is a common neurological disorder, and mutations in genes encoding ion channels or neurotransmitter receptors are frequent causes of monogenic forms of epilepsy. Here we show that abnormal expansions of TTTCA and TTTTA repeats in intron 4 of SAMD12cause benign adult familial myoclonic epilepsy (BAFME). Single-molecule, real-time sequencing of BAC clones and nanopore sequencing of genomic DNA identified two repeat configurations in SAMD12. Intriguingly, in two families with a clinical diagnosis of BAFME in which no repeat expansions in SAMD12were observed, we identified similar expansions of TTTCA and TTTTA repeats in introns of TNRC6Aand RAPGEF2, indicating that expansions of the same repeat motifs are involved in the pathogenesis of BAFME regardless of the genes in which the expanded repeats are located. This discovery that expansions of noncoding repeats lead to neuronal dysfunction responsible for myoclonic tremor and epilepsy extends the understanding of diseases with such repeat expansion.

Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI) has been developing molten carbonate fuel cells as part of Japan's New Sunshine Project since 1987. IHI has successfully completed the first phase of the project with the construction of a 100-kW class large-capacity stack and is now developing two 250-kW stacks and a control system for a 1,000-kW pilot plant. IHI is also conducting R and D to enhance stack lifetime and prepare for the commercialization of the molten carbonate fuel cell plant.

Ishikawajima Harima Heavy Industries Co. Ltd. (IHI) is involved in the development of molten carbonate fuel cells under a contract from the New Energy and Industrial Technology Development Organization and as part of the Japanese Ministry of International Trade and Industry's New Sunshine Program. IHI is taking part in the development of two 250-kW stacks for a 1,000-kW plant, in the design of the plant and in the development of the plant control system.

Tokyo Gas has developed a residential fuel cell CHP system named "ENE-FARM" jointly with Panasonic, and began to sell ENE-FARM as the world's first commercial fuel cell cogeneration system in May 2009. Following the first-generation model of ENE-FARM, the second-generation was released in 2011, and the third-generation in 2013. The cumulative sales of ENE-FARM have reached 40,000 units as of January 2015. After the third-generation, the new fourth-generation model of ENE-FARM has been launched since April 2015. This new model was developed in order to meet customer expectations such as reduced cost, integration of optional units for a power outage and greater flexibility of installation. These improvements can contribute to the customer satisfactions and the expansion of ENE-FARM spread. In this paper, specifications and main features of the new model ENE-FARM are described

Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI) has been developing a large capacity stack of a molten carbonate fuel cell (MCFC) since 1987. The company's research and development project is being supported by the New Energy Development Organization. IHI has already put up a 100-kilowatt class stack and is currently working on the development of another 250-kilowatt stacks for a one-megawatt pilot plant.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

In this paper, we study a consensus problem of continuous time multi-agent system. Multi-agent system has communication network. Each agent gets information of neighbors to achieve consensus. It is assumed that there are delays in communication network. The communication delays are different every communication channels and time-dependent. Furthermore, it is assumed that there are switching topologies and feed-back gains are time variable. Under these assumptions, we show that the entire system is stable. The stability is shown by Lyapunov theorem.

The phosphodiesterase 4B PDE4B interacts with disruptedinschizophrenia 1 DISC1, which is a known genetic risk factor for schizophrenia, bipolar disorder and major depressive disorder MDD. PDE4B is also important in the regulation of cAMP signaling, a second messenger implicated in learning, memory, and mood. In this study, we determined mRNA expression levels of the PDE4B gene in the peripheral blood leukocytes of patients with MDD and control subjects n  33, each. Next we performed twostage casecontrolled association analyses first set; case  174, controls  348; second set; case  481, controls  812 in the Japanese population to determine if the PDE4B gene is implicated in MDD. In the leukocytes, a significantly higher expression of the PDE4B mRNA was observed in the drugnaïve MDD patients compared with control subjects P < 0.0001 and the expression of the MDD patients significantly decreased after antidepressant treatment P  0.030. In the association analysis, we observed significant allelic associations of four SNPs the most significant, rs472952; P  0.002 and a significant haplotypic association permutation P  0.019 between the PDE4B gene and MDD in the firstset samples. However, we could not confirm these significant associations in the following independent secondset of samples. Our results suggest that the PDE4B gene itself does not link to MDD but the elevated mRNA levels of PDE4B might be implicated in the pathophysiology of MDD. © 2008 WileyLiss, Inc.

The paper is concerned with a fully adaptive semi-active control scheme which can deal with uncertainties in both models of MR damper and suspension mechanism. The proposed approach consists of two adaptive control algorithms. The first is an adaptive inverse control for compensating the nonlinear hysteresis dynamics of the MR damper, which can be realized by identifying a forward model of MR damper and then calculating the input voltage to generate a reference damping force. It can also be realized directly by updating an inverse model of MR damper without identification of the forward model, which then works as an adaptive inverse controller. The other is an adaptive reference feedback control which gives the desired damping force to match the seat dynamics to a specified reference dynamics even in the presence of uncertainties in the suspension structure. The stability of the total system including the two adaptation algorithms is discussed and its stability condition is explored. Validity of the proposed algorithm is also examined in simulation studies.

Recent researches have suggested that brain‐derived neurotrophic factor (BDNF) may be implicated in the pathophysiology of mood disorder. This study examined the association between the BDNF Val66Met polymorphism and major depressive disorder (MDD) in a Japanese population. We genotyped the BDNF Val66Met polymorphism in 154 major depressive patients and 154 age‐ and sex‐matched control subjects. The genotypic distributions and allele frequencies were similar among the patients and control subjects. When the relationships of the polymorphism with several clinical variables (i.e., age, sex, age of onset, number of episode, presence of psychotic features, suicidal behavior, and family history) were examined, the dose of Met allele had significant effects on psychotic feature and suicidal behavior and family history. These results suggest that the BDNF Val66Met polymorphism is not related to the development of MDD but related to clinical features of MDD in a Japanese population. © 2007 Wiley‐Liss, Inc.

Titanium (Ti) and TiO, Ti2O3, Ti3O5and TiO1.98as well as TiO2have been evaluated as chemo-affinity sorbents for the selective enrichment of organic phosphates. A column-switching high-performance liquid chromatography (HPLC) system, constructed with a precolumn (4.6 mm i.d. × 10 mm) packed with the titanium sorbents, an anion-exchange analytical column and a UV detector (215 nm) was used. When an aqueous 0.015% trifluoroacetic acid (TFA) was used as a sample-loading solution, O-phospho-L-tyrosine (P-Tyr), phenyl phosphate and phenylphosphonic acid were adsorbed onto all of the titanium sorbents with recoveries of 60.9–102.9%. Some acidic compounds other than phosphates, such as benzenedicarboxylic acid (BDA) isomers, were also adsorbed onto all of the titanium sorbents. To improve the selectivity to organic phosphates, various sample-loading solutions were examined using a Ti precolumn, two phosphorylated peptides [Ile-Ser(p)-Val-Arg (PP1) and Gln-Ile-Ser(p)-Val-Arg (PP2)], P-Tyr, BDA isomers and diglutamic acid (Glu-Glu) as test compounds. Among the sample-loading solutions tested, such as TFA, HClO4, organic acids, boric acid and NaCl, the use of 100 mM NaCl in 10 mM boric acid was found to be effective. The recoveries of PP1, PP2 and P-Tyr were 73.0, 88.3 and 71.5%, respectively, whereas those of Glu-Glu and BDAs were suppressed to only below 10%.

We present a reinforced ion current prediction model in alpha radioactivity measurement using ionized air transportation. Although our previous model explained the qualitative trend of the measured ion current values, the absolute values of the theoretical curves were about two times as large as the measured values. In order to accurately predict the measured values, we reinforced our model by considering columnar recombination and turbulent diffusion, which affects columnar recombination. Our new model explained the considerable ion loss in the early stage of ion diffusion and narrowed the gap between the theoretical and measured values. The model also predicted suppression of ion loss due to columnar recombination by spraying a high-speed air flow near a contaminated surface. This suppression was experimentally investigated and confirmed. In conclusion, we quantitatively clarified the theoretical relation between alpha radioactivity and ion current in laminar flow and turbulent pipe flow.

A novel scheme is described for determining the position of an unknown mobile terminal without any prior information of transmitted signals, keeping in mind, for example, radiowave surveillance. The proposed positioning algorithm is performed by using a single base station with an array of sensors in multipath environments. It works by combining the spatial characteristics estimated from data measurement and ray-tracing (RT) analysis with highly accurate, three-dimensional terrain data. It uses two spatial parameters in particular that characterize propagation environments in which there are spatially spreading signals due to local scattering: the angle of arrival and the degree of scattering related to the angular spread of the received signals. The use of RT analysis enables site-specific positioning using only a single base station. Furthermore, our approach is a so-called blindestimator, that is, it requires no prior information about the mobile terminal such as the signal waveform. Testing of the scheme in a city of high density showed that it could achievem position-determination accuracy more thanof the time even under non-line-of-sight conditions.

AKT‐glycogen synthase kinase 3β (GSK3β) signaling is a target of lithium and has been implicated in the pathogenesis of mood disorders and schizophrenia. AKT1 protein level is decreased in the peripheral lymphocytes and brains of schizophrenic patients. The SNP2/3/4 TCG haplotype of AKT1 was associated with schizophrenia in patients with Northern European origin. In the present study, we genotyped five single nucleotide polymorphisms (SNP1–5) of AKT1 gene according to the original study in Iranians comprising of 321 schizophrenic patients and 383 controls, all residing in Mashhad city, Northeastern Iran. Haplotype analysis showed that the frequency of a five‐SNP haplotype (AGCAG) was significantly higher in schizophrenic patients (0.068) than that of controls (0.034) (P = 0.03 after Bonferroni correction, OR = 2.04, CI = 1.2–3.4). In stratified analysis by schizophrenia subtypes, the frequency of the same haplotype was significantly higher in disorganized subtype (n = 78, frequency of haplotype=0.081) when compared with normal controls (P = 0.04 after Bonferroni correction, OR = 2.59, CI = 1.3–5.2). Our findings did not confirm the association of AKT1 SNP2/3/4 TCG haplotype with the risk of schizophrenia as reported in the original study but showed the evidence of association with a different haplotype, AKT1 five‐SNP AGCAG haplotype, with the risk of schizophrenia in Iranian population. © 2006 Wiley‐Liss, Inc.

This paper proposes an algorithm for iteratively identifying the physical parameters of an elastically coupled two-mass torsional system directly from input-output data. The identification process is conducted under close-loop conditions with a 2-degree-of-freedom controller that incorporates a suitable reference model. It is shown that with convergence of the output error to zero, the controller parameters give a precise estimate of the true physical parameters. The tuning of controller parameters is accomplished in an iterative manner similar to the Iterative Feedback Tuning (IFT), utilizing a linearized plant transfer function obtained through direct closed-loop identification based on the output oversampling approach. The effectiveness of the proposed method in identifying the physical parameters of a two-mass motor system is verified via experimentation.

The direct closed-loop identification algorithm in frequency domain is considered in this paper. It is illustrated that the input and output signals obtained through inter-sampling technique have cyclic spectrum. Then a cyclic spectrum based identification algorithm to identify the plant model in closed-loop is proposed. It is clarified that the test signal is not necessary, and the new algorithm does not depend on the controller structure as in the conventional methods. The effectiveness of the proposed algorithm is demonstrated through numerical examples.

By exploiting the array geometry and its shift invariance property of a uniform linear array (ULA), a new computationally efficient subspace-based algorithm is investigated for estimating the constant directions adaptively and for tracking the slowly time-varying directions promptly, where the null space is estimated with the least-mean-square (LMS) or normalized LMS (NLMS) algorithm, and the directions are updated by the approximate Newton’s method. The transient analyses of LMS and NLMS algorithms are studied, where the weights are in the form of matrix, and there is the correlation between the “additive noise” and “input data” that involve the instantaneous correlation of received array data in the updating equation, and the stability conditions of step-size are derived explicitly. Additionally the analytical expressions of mean-square error (MSE) and mean-square deviation (MSD) learning curves of LMS algorithm are also clarified.

In this paper, an efficient subspace-based method is proposed for estimating the directions-of-arrival (DOAs) of coherent narrowband cyclostationary signals impinging on a uniform linear array (ULA) without eigendecomposition and spatial smoothing (SS) processes. The proposed method uses the inherently temporal property (i.e., cyclostationarity) of incident signals and a subarray scheme to decorrelate the signal coherency and to suppress the noise and interfering signals, while the null space is obtained from the resulting cyclic correlation matrix through a linear operation. Then an on-line implementation of this method is presented for tracking the DOAs of slowly moving (relative to the sampling rate) coherent signals. The effectiveness of the proposed on-line algorithm is verified through numerical examples, and it is shown that the proposed algorithm is computationally simple and has a good tracking performance.

New time-domain and frequency-domain direct adaptive algorithms are proposed for general multichannel active noise control (ANC) when all of the sound path dynamics are uncertain and changeable. To reduce the cancelling errors, two kind of virtual errors are introduced and are forced to zero by adjusting three adaptive FIR filter matrices in an online manner, by which the convergence of the actual cancelling error to zero can be attained at the objective points. Unlike other conventional approaches, the proposed algorithms can give an inverse controller directly without need of explicit identification of the secondary path channels. In addition, the proposed algorithm which is implemented in the frequency-domain has the reduced computational complexity.

A new time-domain adaptive predistortion scheme is presented for compensating nonlinearity of high power amplifiers (HPA) in OFDM systems. A power series model with memory (PSMWM) is proposed to approximate the HPA expressed by a complex Wiener-Hammerstein model (WHM) which can describe the input-output relationship of unknown HPA with linear dynamics. By using the PSMWM, the compensation input to HPA is calculated in a real-time manner so that the linearization from the predistortor input to the HPA output can be attained even if the nonlinear input-output relation of HPA is uncertain and changeable. The effectiveness of the proposed adaptive compensation scheme is validated by numerical simulation for 64QAM–OFDM systems and compared with other methods.

A method for the determination of phosphorylation sites in phosphoproteins based on column-switching high-performance liquid chromatography (HPLC) has been developed. The HPLC system consisted of a titania precolumn for the selective adsorption of phosphopeptides, an anion-exchange analytical column and a UV detector (215 nm). Rabbit muscle phosphorylase a(RPa) and porcine stomach pepsin (PSP) were tested as model phosphoproteins. After protease digestion, the resulting phosphopeptides were successfully isolated by column-switching HPLC. The phosphopeptide fractions were analyzed by electrospray ionization mass spectrometry with a positive or negative ion mode after purification by reversed-phase HPLC. Pseudo-molecular ion peaks corresponding to Gln-Ile-Ser(p)-Val-Arg (MW 681.7) and Glu-Ala-Thr-Ser(p)-Gln-Glu-Leu (MW 856.8) were detected from the tryptic digest of RPa and chymotryptic digest of PSP, respectively, which agreed with the theoretically expected phosphopeptide fragments.

A computationally simple direction-of-arrival (DOA) estimation method with good statistical performance is attractive in many practical applications of array processing. This paper studies the statistical properties of a new computationally efficient subspace-based method without cigendecomposition (SUMWE) for estimating the directions of narrowband signals impinging on a uniform linear array (ULA), where he asymptotic mean-squared-error (MSE) expression of the estimation error is derived. The theoretical analysis is substantiated through numerical examples, and it is shown that the SUMWE can resolve closely spaced coherent signals better with a smaller number of snapshots and at lower signal-to-noise ratio (SNR).

Fully adaptive feedforward control algorithm is proposed for general multichannel active noise control (ANC) when all the noise transmission channels are uncertain. To reduce the actual canceling error, two kinds of virtual errors are introduced and are forced into zero by adjusting three adaptive FIR filter matrices in an on-line manner, which can result in the canceling at the objective points. Unlike other conventional approaches, the proposed algorithm does not need exact identification of the secondary paths, and so requires neither any dither signals nor the PE property of the source noises, which is a great advantage of the proposed adaptive approach.

The paper is concerned with adaptive cancellation of coupling effect in SFN relay station of an OFDM system. Due to the band limit of the source signal, the precise estimation of coupling wave channel outside the signal bandwidth is almost infeasible and that makes the performance of coupling effect cancellation very poor, even deteriorates the system stability. A new approach to estimate the channel model and to evaluate its estimation error is proposed for stable canceller updating.

Our previous study has suggested that the TaqI A polymorphism of dopamine D2 receptor gene (DRD2) is associated with the predisposition to neuroleptic malignant syndrome (NMS). However, the specificity of this polymorphism as a predictor of NMS dose not seem to be sufficient enough. Meanwhile, it has been shown that the non-carriers of Del allele of the −141C Ins/Del polymorphism in the promoter region of DRD2 have lower dopamine D2 receptor in the brain than the carriers. In addition, dopamine D3 receptor gene has a Ser9Gly polymorphism, which may alter the receptor function. The present study examined the association between these three polymorphisms and the development of NMS to investigate if a combination of these polymorphisms could increase the specificity as markers for NMS. The subjects were 17 psychiatric patients who had developed NMS (13 patients with schizophrenia, 3 with major depression, and 1 with dementia of the Alzheimer's type) and 163 schizophrenic patients who had never developed this syndrome. The frequency of the A1 allele was significantly (P = 0.012) higher in the patients who had developed NMS (59%) than in the patients who had not (35%). The proportion of the A1 carriers was significantly (P = 0.003) higher in the patients with NMS (16/17: 94%) than in those without the syndrome (93/163: 57%). However, no significant differences were found in the allele and genotype frequencies of the other two polymorphisms between the two groups. The present study suggests that only the TaqI A polymorphism is at least partly useful as a predictor of NMS, but the −141 C Ins/Del and Ser9Gly polymorphisms are not. © 2003 Wiley-Liss, Inc.

Proposes a direct closed-loop identification method by using an output intersampling technique. Removal of the traditional restrictive identifiability condition in the technique; Insignificance of the external persistently exciting test signal in the technique; Advantages of the proposed direct closed-loop identification scheme.

We suggest a method to design supervisor which guarantees robust stability for linear time-invariant systems in the presence of the uncertainty via output feedback. The system is a composite of continuous-time uncertain plant and switched controller. The controller is defined by a collection of given controllers whose state is shared. Furthermore the proposed supervisor controller determines the mode of the controller to guarantee robust stability of the total closed-loop system. A sufficient condition of robust stability is given in terms of an algebraic Riccati equation and bilinear matrix inequalities(BMI).

A new auto-tuning algorithm for motor velocity control is presented to adjust the parameters in the feedforward and feedback PI controllers, according to identified physical parameters such as a motor time constant, viscous friction terms proportional to motor velocity and squared velocity, and Coulomb friction. The physical parameters are identified by the proposed adaptive algorithm which appropriately set up a reference model and use its state variables to adjust the feedforward controller parameters. The proposed scheme is robust to disturbance torque, compared to ordinary closed-loop identification using the motor output directly. Its effectiveness is investigated in velocity control experiment using an AC synchronous servo motor.

New adaptive identification algorithms are proposed for a time-varying linear system in which the system parameters change as piecewise polynomial function of time. By appropriately incorporating the internal model corresponding to the polynomial degree into the parameter adjustment dynamics of the new algorithm, its BIBO stability can be assured by the aid of the small gain theorem and modified passivity theorem. Its effectiveness of the proposed LMS and RLS types of adaptive algorithms is validated by comparing to ordinary approaches in adaptive direction-of-arrival (DOA) estimation for fast moving targets.

This paper is concerned with a new adaptive predistortion method for compensation of linear and nonlinear distortions of a high power amplifier (HPA), which is frequently used in the orthogonal frequency division multiplexing (OFDM) communication scheme and mobile communication systems. The proposed nonlinear method is based on the support vector machine (SVM), which can construct an inverse system of the nonlinear amplifier through learning using a given number of training samples. An on-line adaptive algorithm for updating the parameters of SVM is also investigated to reduce its computational burden of the batch-processed optimization. By comparing with a case without predistortion and ordinary table-lookup scheme, it is shown that the proposed data-based approach can improve the suppression of the power spectrum of the amplifier output outside the input frequency band caused by the nonlinear distortions.

A fluorometric method for the determination of N-nitroso-N-methylurea (NMU) has been developed. It is based on the N-methylation reaction of nicotinamide with NMU and a subsequent condensation reaction with acetophenone, followed by an acid treatment to form a fluorescent 2,7-naphthyridine derivative. This method enabled the determination of NMU in the range 0.05–2 nmol/200 µl with a relative standard deviation of ca. 3%. It was applied to the determination of NMU formed from a precursor N-methylurea (MU) under simulated gastric conditions containing nitrite and thiocyanate ions at pH 3.0 in the presence of fresh orange juice and milk. NMU was extracted by an Extrelut 20 column and then determined. The mean recoveries of NMU added to the simulated gastric juice containing water, orange juice and milk were 86.5, 85.1 and 69.8%, respectively. The amounts of NMU formed from MU were found to decrease to below 25% in the presence of orange juice and milk.

Fluorescence and chemiluminescence responses of thiols derivatized with o-phthalaldehyde (OPA) and primary amines have been studied. Among thiols tested, those having an α-ketothiol structure [R-CH(SH)-CO-] were found to give extremely low fluorescence intensities when derivatized with OPA and L-valine. The relative fluorescence intensities of α-ketothiols, such as mercaptoacetic acid (MAA), 2-mercaptopropionic acid (2-MPA), mercaptosuccinic acid (MSA) and N-(2-mercaptopropionyl)glycine (MPG), were only below 3% of that of N-acetyl-L-cysteine (NAC), having no α-ketothiol structure. The addition of detergents such as sodium dodecylsulphate had no effect on the fluorescence and an aprotic solvent (dimethylsulphoxide) showed little effect, whereas these thiols chemiluminesced intensely when derivatized with OPA and N-(4-aminobutyl)-N-ethylisoluminol as a primary amine and successively detected by high-performance liquid chromatography (HPLC) with postcolumn chemiluminescence reactions using hydrogen peroxide and haematin. The relative chemiluminescence intensities of MSA, 2-MPA and MPG to NAC were 41.0%, 27.8% and 117%, respectively. MPG was estimated to be detectable at a concentration level of at least 10 fmol per injection. In conclusion, the weak fluorescence of the α-ketothiols derivatized with OPA and primary amines is probably due to the low fluorescence quantum yields of the derivatives, and HPLC with a chemiluminescence detection system is useful for the sensitive detection of thiols. Copyright © 2001 John Wiley & Sons, Ltd.

Fluorescence and chemiluminescence responses of thiols derivatized with o‐phthalaldehyde (OPA) and primary amines have been studied. Among thiols tested, those having an α‐ketothiol structure [R‐CH(SH)‐CO‐] were found to give extremely low fluorescence intensities when derivatized with OPA and L‐valine. The relative fluorescence intensities of α‐ketothiols, such as mercaptoacetic acid (MAA), 2‐mercaptopropionic acid (2‐MPA), mercaptosuccinic acid (MSA) and N‐(2‐mercaptopropionyl)glycine (MPG), were only below 3% of that of N‐acetyl‐L‐cysteine (NAC), having no α‐ketothiol structure. The addition of detergents such as sodium dodecylsulphate had no effect on the fluorescence and an aprotic solvent (dimethylsulphoxide) showed little effect, whereas these thiols chemiluminesced intensely when derivatized with OPA and N‐(4‐aminobutyl)‐N‐ethylisoluminol as a primary amine and successively detected by high‐performance liquid chromatography (HPLC) with postcolumn chemiluminescence reactions using hydrogen peroxide and haematin. The relative chemiluminescence intensities of MSA, 2‐MPA and MPG to NAC were 41.0%, 27.8% and 117%, respectively. MPG was estimated to be detectable at a concentration level of at least 10 fmol per injection. In conclusion, the weak fluorescence of the α‐ketothiols derivatized with OPA and primary amines is probably due to the low fluorescence quantum yields of the derivatives, and HPLC with a chemiluminescence detection system is useful for the sensitive detection of thiols. Copyright © 2001 John Wiley & Sons, Ltd.

A class of identification algorithms for the closed-loop identification problem is discussed based on the output inter-sampling scheme. It is illustrated that the inter-sampled linear plant has a special single-input multiple-output model structure with common control input, and the inter-sampled output has cyclostationary property. Thus it can be clarified that the identifiability of the algorithm can be guaranteed by the multiple model structure in the time domain, and the cyclostationary property can be used to eliminate the correlation between the plant input and output noise in the frequency domain even though no persistently exciting reference signal is available. Some simulation and experiment results demonstrate the effectiveness of the proposed algorithms.

By exploiting the inherently temporal properties exhibited by most communication signals, in this paper, we propose a new cyclic approach for estimating the directions of coherent narrow-band signals without eigendecomposition and spatial smoothing processes. In which, the cyclostationarity and subarray scheme are combined to decorrelate the signal coherency and to suppress the noise and interfering signals, while the noise subspace is estimated from the resulting cyclic correlation matrix by a linear operation. As a result, the proposed approach has the advantages of computational simplicity and robust detection capability. The performance of the presented approach is verified through numerical examples.

A new deterrninistic adaptive identification and equalization approach is investigated based on an internal model principle to take account of time-varying dynamics of the channel parameters. The proposed adaptive algorithm incorporates an internal model for compensating the dynamics of the time-varying parameters of the FIR channel model. The stability of the adaptation can be assured by designing the parameter adjusting dynamics in the actaptive algorithm by the help of the small gain theorem and passivity theorem. Its effectiveness of the proposed algorithms is examined and compared to ordinary LMS approaches in numerical simulation of adaptive identification and equalization of a fading channel with parameters changing with a first-order function of time.