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Purpose: The genome-wide DNA methylation status (GWMS) predicts of therapeutic response to anti-epidermal growth factor receptor (EGFR) antibodies in treating metastatic colorectal cancer. We verified the significance of GWMS as a predictive factor for the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer. Methods: Clinical data were obtained from a prospective trial database, and a genome-wide DNA methylation analysis was performed. GWMS was classified into high-methylated colorectal cancer (HMCC) and low-methylated colorectal cancer (LMCC). The patients were divided into subgroups according to the treatment arm (cetuximab plus irinotecan or irinotecan alone) and GWMS, and the clinical outcomes were compared between the subgroups. Results: Of the 112 patients, 58 (51.8%) were in the cetuximab plus irinotecan arm, and 54 (48.2%) were in the irinotecan arm; 47 (42.0%) were in the HMCC, and 65 (58.0%) were in the LMCC group regarding GWMS. Compared with the LMCC group, the progression-free survival (PFS) was significantly shortened in the HMCC group in the cetuximab plus irinotecan arm (median 1.4 vs. 4.1 months, p = 0.001, hazard ratio = 2.56), whereas no significant differences were observed in the irinotecan arm. A multivariate analysis showed that GWMS was an independent predictor of PFS and overall survival (OS) in the cetuximab plus irinotecan arm (p = 0.002, p = 0.005, respectively), whereas GWMS did not contribute to either PFS or OS in the irinotecan arm. Conclusions: GWMS was a predictive factor for the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer. [ABSTRACT FROM AUTHOR]

Functional properties caused by TP53 mutations are involved in cancer development and progression. Although most of the mutations lose normal p53 functions, some of them, gain-of-function (GOF) mutations, exhibiting novel oncogenic functions. No reports have analyzed the impact of TP53 mutations on the gene expression profile of the p53 signaling pathway across cancer types. This study is a cross-cancer type analysis of the effects of TP53 mutations on gene expression. A hierarchical cluster analysis of the expression profile of the p53 signaling pathway classified 21 cancer types into two clusters (A1 and A2). Changes in the expression of cell cycle-related genes and MKI67 by TP53 mutations were greater in cluster A1 than in cluster A2. There was no distinct difference in the effects between GOF and non-GOF mutations on the gene expression profile of the p53 signaling pathway. [ABSTRACT FROM AUTHOR]

Two infrared active translational modes of solid CS2, B1u(Γ-3) and B2u(Γ-2) were precisely measured from the temperature of liquid helium to the melting point. Remarkable temperature dependencies of the absorption bandwidths were obtained and explained by means of the perturbation theory of the anharmonic crystal. The results suggest ways in which the lattice vibration energy is dissipated or transferred. [ABSTRACT FROM AUTHOR]

Background: Recombinant human soluble thrombomodulin (rTM) has been established and introduced in the clinic as a standard treatment for disseminated intravascular coagulation (DIC). However, the efficacy and safety of rTM for DIC associated with solid tumors (DIC-STs) have not been fully established. Here, we performed a retrospective analysis of the clinical outcomes of rTM for DIC-STs and considered a treatment strategy with rTM for DIC-STs.Methods: Patients with DIC-STs between November 2009 and March 2016 in 2 cancer core hospitals were retrospectively analyzed. Data, including patient background, treatment course, and clinical outcomes of rTM for DIC-STs, were extracted. The clinical outcomes were evaluated by comparing the DIC score, resolution rate, and overall survival (OS) duration.Results: The study included 123 patients with DIC-STs. The median OS in all patients was 41 days. The DIC resolution rate was 35.2%. DIC scores and DIC-related blood test data (fibrin degradation product and prothrombin time-international normalized ratio) significantly improved at the end of rTM administration (P < 0.001). The OS duration was longer in patients who were treated with chemotherapy after DIC onset than in those who were not treated with chemotherapy (median, 178 days vs. 17 days, P < 0.001). In both univariate and multivariate analyses, chemotherapy after DIC onset showed the strongest association with OS.Conclusions: rTM can at least temporarily improve or maintain the state of DIC-STs. It is suggested that prolongation of survival can be expected when control of DIC and treatment of the underlying disease are compatible. [ABSTRACT FROM AUTHOR]

The case of a patient in whom hemodynamic and electrocardiographic studies using the occlusion test for coronary artery fistulas (CAF) were safely performed prior to catheter embolization is reported. A 1-year-old girl had a separate right coronary artery arising from a left single coronary artery that formed a significant coronary artery fistula to the right ventricle. Coronary steal by the large coronary artery fistula narrowed the left coronary artery. The right coronary artery branches could not be clearly identified due to an overlap with the fistula. Due to the long porous CAF, embolic procedures could cause serious complications. We confirmed the safety by performing an occlusion test of the CAF’s proximal blood vessels. Following total occlusion of the CAF for 10 minutes, pulmonary arterial pressure and aortic blood pressure were not significantly changed. No bradycardia, atrioventricular block, or ST changes were observed. Coil embolization treatment was performed safely. For patients with long distal CAF complicated with a single coronary artery, myocardial ischemia and conduction system disorders can be identified by performing the occlusion test before embolization. [ABSTRACT FROM AUTHOR]

Background: We conducted a nationwide questionnaire-based survey to understand the current situation regarding central venous port implantation in order to identify the ideal procedure. Methods: Questionnaire sheets concerning the number of implantation procedures and the incidence of complications for all procedures completed in 2012 were sent to 397 nationwide designated cancer care hospitals in Japan in June 2013. Venipuncture sites were categorized as chest, neck, upper arm, forearm, and others. Methods were categorized as landmark, cut-down, ultrasound-mark, real-time ultrasound guided, venography, and other groups. Results: We received 374 responses (11,693 procedures) from 153 centers (38.5 %). The overall complication rates were 7.4 % for the chest (598/8,097 cases); 6.8 % for the neck (157/2325); 5.2 % for the upper arm (54/1,033); 7.3 % for the forearm (9/124); and 6.1 % for the other groups (7/114). Compared to the chest group, only the upper arm group showed a significantly lower incidence of complications ( P = 0.010), and multivariate logistic regression (odds ratio 0.69; 95 % confidence interval 0.51-0.91; P = 0.008) also showed similar findings. Real-time ultrasound-guided puncture was most commonly used in the upper arm group (83.8 %), followed by the neck (69.8 %), forearm (53.2 %), chest (41.8 %), and other groups (34.2 %). Conclusion: Upper arm venipuncture with ultrasound guidance seems the most promising technique to prevent complications of central venous port implantation. [ABSTRACT FROM AUTHOR]

Background: Comprehensive gene-expression analysis is very useful for classifying specific cancers into subgroups on the basis of their biological characteristics; it is used both prognostically and predictively. The purpose of this study was to classify unresectable advanced or recurrent colorectal cancer (CRC) by gene-expression profiling of formalin-fixed paraffin-embedded tissues and to correlate CRC subgroups with clinicopathological and molecular features and clinical outcomes. Methods: One hundred patients with advanced or recurrent CRC were enrolled. RNA extracted from FFPE tissues was subjected to gene-expression microarray analysis. Results: The patients were stratified into four subgroups (subtypes A1, A2, B1, and B2) by unsupervised hierarchical clustering. By use of principle-components analysis (PCA), the patients were divided into subtypes A and B on the basis of component 1 and into subtypes 1 and 2 on the basis of component 2. Subtype A was significantly enriched among patients without the KRAS mutation and with an earlier clinical stage at diagnosis. With regard to anti-EGFR therapy, progression-free survival (PFS) was better for patients in subtype A without the KRAS mutation than for those with the KRAS mutation ( P = 0.047). PFS for patients without the KRAS mutation in subtype B was comparable with that for patients with the KRAS mutation ( P = 0.55). Similar results were observed in a validation set. Conclusion: We found that gene-expression profiles enabled stratification of CRC patients into four subgroups. The efficacy of anti-EGFR therapy was correlated with component 1 from PCA. This comprehensive study may explain the heterogeneity of unresectable advanced or recurrent CRC and could be useful for identifying novel biomarkers for CRC treatment. [ABSTRACT FROM AUTHOR]

Vanadium-substituted LiFe 0.5 Mn 0.5 SiO 4 cathode material for Li-ion batteries is synthesized by solid state reaction, and the effect of V-substitution on the material is investigated by X-ray diffraction and charge–discharge tests. X-ray diffraction patterns seem to indicate that V +5 is substituted for Si 4+ in Li 2+x Fe 0.5−x/2 Mn 0.5−x/2 Si 1−x V x O 4 (x = 0, 0.1, 0.2, 0.3, 0.4) by maintaining electroneutrality. The substitution of V for Si in Li 2 Fe 0.5 Mn 0.5 SiO 4 increases the charge and discharge capacities as a cathode material of Li-ion batteries; Li 2.2 Fe 0.4 Mn 0.4 Si 0.8 V 0.2 O 4 delivers an initial discharge capacity of 197 A h/kg, while Li 2 Fe 0.5 Mn 0.5 SiO 4 delivers that of 134 A h/kg. The main reason for the high capacity with the V substitution for Si in Li 2 Fe 0.5 Mn 0.5 SiO 4 is considered not due to the redox capacity of V but due to the lowering of the charge voltage, while, substituting a higher amount of V, with x over 0.2 in Li 2+x Fe 0.5−x/2 Mn 0.5−x/2 Si 1−x V x O 4 , reduces capacity in accordance with theoretical capacity calculation. In order to confirm the V-substitution site exactly, however, strong evidence by Rietveld refinement is necessary, which is left as our urgent future work. [ABSTRACT FROM AUTHOR]

We have created a visual interface using the human palm that is location sensitive and always available. To accomplish this, we constructed an augmented space in an actual workspace by installing several depth cameras. To manage and connect the multiple depth cameras, we constructed a distributed system based on scalable client--server architecture. By merging depth images from different cameras, the distributed system can track the locations of users within their area of coverage. The system also has a convenient feature that allows users to collect the locations of objects while visualizing the objects via images from the depth cameras. Consequently, the locations of both users and objects are available to the system, thus providing a location-based context for determining which user is close to which object. As a result, the visual interface on the palm becomes location sensitive, which could lead to various applications in daily life. In this paper, we describe the implementation of the aforementioned system and demonstrate its potential applicability. [ABSTRACT FROM AUTHOR]

Background: The requirement of central venous (CV) port implantation is increasing with the increase in the number of cancer patients and advancement in chemotherapy. In our division, medical oncologists have implanted all CV ports to save time and consultation costs to other departments. Recently, upper arm implantation has become the first choice as a safe and comfortable method in our unit. Here we report our experience and discuss the procedure and its potential advantages. Methods: All CV port implantations (n = 599) performed in our unit from January 2006 to December 2011 were analyzed. Procedural success and complication rates between subclavian and upper arm groups were compared. Results: Both groups had similar patient characteristics. Upper arm CV port and subclavian implantations were equivalently successful and safe. Although we only retrospectively analyzed data from a single center, the upper arm group had a significantly lower overall postprocedural complication rate than the subclavian group. No pneumothorax risk, less risk of arterial puncture by ultrasound, feasibility of stopping potential arterial bleeding, and prevention of accidental arterial cannulation by targeting the characteristic solitary basilic vein were the identified advantages of upper arm CV port implantation. In addition to the aforementioned advantages, there is no risk of “pinch-off syndrome,” possibly less patient fear of manipulation, no scars on the neck and chest, easier accessibility, and compatibility with the “peripherally inserted central catheter” technique. Conclusions: Upper arm implantation may benefit clinicians and patients with respect to safety and comfort. We also introduce our methods for upper arm CV port implantation with the videos. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the occurrence of polychlorinated biphenyls (PCBs), and several additive brominated flame retardants (BFRs) in indoor dust and air from two Vietnamese informal e-waste recycling sites (EWRSs) and an urban site in order to assess the relevance of these media for human exposure. The levels of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), 1,2-bis-(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenyl ethane (DBDPE) in settled house dust from the EWRSs (130–12,000, 5.4–400, 5.2–620 and 31–1400ngg−1, respectively) were significantly higher than in urban house dust but the levels of PCBs (4.8–320ngg−1) were not higher. The levels of PCBs and PBDEs in air at e-waste recycling houses (1000–1800 and 620–720pgm−3, respectively), determined using passive sampling, were also higher compared with non-e-waste houses. The composition of BFRs in EWRS samples suggests the influence from high-temperature processes and occurrence of waste materials containing older BFR formulations. Results of daily intake estimation for e-waste recycling workers are in good agreement with the accumulation patterns previously observed in human milk and indicate that dust ingestion contributes a large portion of the PBDE intake (60%–88%), and air inhalation to the low-chlorinated PCB intake (>80% for triCBs) due to their high levels in dust and air, respectively. Further investigation of both indoor dust and air as the exposure media for other e-waste recycling-related contaminants and assessment of health risk associated with exposure to these contaminant mixtures is necessary. [Copyright &y& Elsevier]

The noninvasive evaluation of ventricular T-wave alternans (TWA) in patients with lethal ventricular arrhythmias is an important issue. In this study, we propose a novel algorithm to identify T-wave current density alternans (TWCA) using synthesized 187-channel vector-projected body surface mapping (187-ch SAVP-ECG). We recorded 10 min of 187-ch SAVP-ECG using a Mason-Likar lead system in the supine position. A recovery time (RT) dispersion map was obtained by averaging the 187-ch SAVP-ECG. The TWCA value was determined from the relative changes in the averaged current density in the T-wave zone (Tpeak ± 50 ms) for two T-wave types. We registered 20 ECG recordings from normal controls and 11 ECG recordings from nine subjects with long QT syndrome (LQT). We divided LQT syndrome subjects into two groups: group 1 provided 9 ECG recordings without visually apparent TWAs, and group 2 provided 2 ECG recordings with visually apparent TWAs. The QTc interval values in the LQT groups were higher than those in the control (515 ± 60 ms in LQT G-1, 600 ± 27 ms in LQT G-2 vs. 415 ± 19 ms in control, P < 0.001). The RTendc dispersion values among the LQT subjects were higher than those of the control subjects (48 ± 19 ms in LQT G-1, 65 ± 30 ms in LQT G-2 vs. 24 ± 10 ms in control, P < 0.01). The mean TWCA value was significantly higher in the LQT G-2 group with visually apparent TWCAs (0.5 ± 0.2% in control, 2.1 ± 1.2% in LQT G-1, and 32.3 ± 6.9% in LQT G-2). Interestingly, the two-dimensional distribution of TWCA in LQT was inhomogeneous and correlated with the distribution of increased RT dispersion. We conclude that a novel algorithm using 187-ch SAVP-ECG might provide new insights into body surface TWCA. [ABSTRACT FROM AUTHOR]

Abstract: An initial oxidation dynamics of 4H-SiC(0001)-(√3×√3)R30° surface has been studied using high resolution X-ray photoelectron spectroscopy and supersonic molecular beams. Clean 4H-SiC(0001)-(√3×√3)R30° surface was exposed to oxygen molecules with translational energy of 0.5eV at 300K. In the first step of initial oxidation, oxygen molecules are immediately dissociated and atomic oxygens are inserted into Si–Si back bonds to form stable oxide species. At this stage, drastic increase in growth rate of stable oxide species by heating molecular beam source to 1400K was found. We concluded that this increase in growth rate of stable oxide is mainly caused by molecular vibrational excitation. It suggests that the dissociation barrier is located in the exit channel on potential energy hypersurface. A metastable molecular oxygen species was found to be adsorbed on a Si-adatom that has two oxygen atoms inserted into the back bonds. The adsorption of the metastable species is neither enhanced nor suppressed by molecular vibrational excitation. [Copyright &y& Elsevier]

Abstract: Supersonic molecular beam technique combined with high resolution X-ray photoelectron spectroscopy using synchrotron radiation was applied to the study of the dynamics of dissociative adsorption of oxygen on Ru(0001) surface in high coverage region. The Ru(0001) surface pre-covered with oxygen atoms of 0.5monolayer, which corresponds to the p(2×1)-O structure, was dosed to oxygen molecules with translational energy of 0.5eV. Oxygen uptake was compared between the cases with and without the beam source heated in order to verify the effects of internal energy of oxygen. We found drastic enhancement in initial sticking probability of oxygen when the beam source was heated to 1400K. We concluded that the enhancement of sticking probability is mainly caused by molecular vibrational excitation, indicating that dissociation barrier is located in the exit channel on potential energy surface. [Copyright &y& Elsevier]

Abstract: Dissociative adsorption of oxygen on Ru(0001) surface was investigated by supersonic molecular beam method combined with high resolution X-ray photoelectron spectroscopy (XPS) using synchrotron radiation. We examined the effects of molecular vibrational excitation as well as translational energy on dissociative adsorption of oxygen in the direct adsorption regime. We found an enhancement of dissociative oxygen adsorption on Ru(0001) by molecular vibrational excitation, indicating that potential energy surface has a late barrier for this system. [Copyright &y& Elsevier]

Abstract: An intercalibration study on organobromine compounds has been conducted to evaluate the accuracy and reliability in the analysis of brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) and their related compounds like polybrominated and monobromo-polychlorinated dibenzodioxins and -furans (PBDDs/DFs, MoBPCDDs/DFs). This paper reports the results for these compounds in ‘Mixed Standard Solutions’ and ‘Air-Dried Sediment’. The relative standard deviations (RSDs) for PBDEs, PBDDs/DFs and MoBPCDDs/DFs in mixed standard solutions ranged from 9% to 24%, 4% to 20% and 8% to 27%, respectively. The results of this study are better than those reported in earlier international interlaboratory studies due to general improvement in analytical methods and an increasing number of available authentic standards, particularly for PBDEs. In the analysis for higher brominated compounds such as octabromodibenzodioxin, the participants were advised to optimize the calibration curves befitting the range of concentrations found in samples because variation of relative response factors was noted. The results for ‘Air-Dried Sediment’ were also reasonable with RSDs from 10% to 38% for PBDEs, 8% to 38% for PBDDs/DFs and 17% to 36% for MoBPCDDs/DFs. In the sediment sample, possible errors in the sample pretreatment and/or interference by other compounds/impurities were indicated. The concentrations of pentabromodiphenylether, BDE100, varied more than the other PBDE isomers due to its poor separation in some chromatographic conditions. In addition, interference by PBDEs was observed in the analysis for PBDFs. Potential degradation/secondary formulation of PBDEs and PBDFs during the Soxhlet extraction were suggested when copper powder was added into the sediment samples. Inspite of these observations, the results in this study are better than those reported in other interlaboratory studies due to the advice given to participants for improving the results. Compared with the results for PCDDs/DFs (5–23% RSDs) and Co-PCBs (6–24% RSDs), the RSDs for most of the organobromine compounds were high, indicating an immature QA/QC approach for the analysis of PBDEs and related compounds in comparison to common chlorinated dioxins. [Copyright &y& Elsevier]

The concentrations of butyltins along the Japanese coastline were investigated from 1997 to 1999, 7 to 9 years after implemantion of legislation limiting the use of tributyltin (TBT) in Japan. Seawater was sampled at 0.5 m depth, and Caprella spp. were collected from Sargassum spp. and aquaculture facilities from 18 areas within four broad areas along the coastline of Japan, i.e., the Pacific coast of northern Japan, the coast along the Sea of Japan, Tokyo Bay and adjacent areas, and western Japan. Butyltins (MBT, DBT and TBT) were detected in 32 of the 63 seawater samples with average concentrations of 4.6 ng MBT/l, 4.5 ng DBT/l and 6.8 ng TBT/l, respectively. Butyltin concentrations in seawater from western Japan indicate “hot spots” even in unpopulated areas. Butyltins (MBT, DBT and TBT) were detected in all samples of Caprella spp., varying from 2.3 ng BTs /g wet wt in C. penantis R-type from Tobishima Island in the Sea of Japan to 464 ng BTs /g wet wt in C. decipiens Mayer from Amakusa, western Kyushu. The BT concentrations in Caprella spp. form western Japan were significantly higher than those from other areas, including Tokyo Bay and adjacent areas, where large scale industry and international ports are located. These results indicate that butyltin contamination still remains even in unpopulated areas after the regulation on TBT usage, and that the regulation governing TBT usage since 1990 has not been effective enough to concede recovery of shallow water ecosystems around Japan. [Copyright &y& Elsevier]

Immobilization of metal complexes on a carbon electrode was successfully carried out via their ligand, of which the functional group on the opposite side of the central metal ion is covalently bonded to the carbon electrode. This method is viewed as a ligand grafting method. The functional group is primary or secondary amine, but not tertiary amine. As metal complexes, Os(bpy)2Cl2 (bpy&z.tbnd6;4,4′-bipyridyl), Ru(bpy)2Cl2, and Os(phen)2Cl2 were used, and as ligands, which act as a bridge between the complex and the carbon electrode, 4-aminopyridine and 4-aminoethylpyridine, were used. Two ligand grafting methods were developed: in one, a ligand by itself was first grafted on carbon through electrochemical cation radical formation in ethanol solution, and then metal complex was refluxed with ligand-grafted carbon to generate metal complex grafted carbon. A second method is for the metal complex to be directly bonded to carbon by the electrochemical cation radical formation. [Copyright &y& Elsevier]

Butyltin compounds (BTs) including mono-, di-, and tributyltin and total tin (ΣSn), were determined in green mussels (Perna viridis) from various Asian developing countries, such as Cambodia, China (Hong Kong and southern China), Malaysia, India, Indonesia, the Philippines, and Vietnam, to elucidate the contamination status, distribution, and possible sources and to assess the risks on aquatic organisms and humans. Butyltin compounds were detected in green mussels collected from all the sampling location investigated, suggesting widespread contamination of BTs along the coastal waters of Asian developing countries. Among butyltin derivatives, tributyltin (TBT) was the predominant compound, indicating its ongoing usage and recent exposures in Asian coastal waters. Higher concentrations of BTs were found in mussels collected at locations with intensive maritime activities, implying that the usage of TBT as a biocide in antifouling paints was a major source of BTs. In addition, relatively high concentrations of BTs were observed in mussels from aquaculture areas in Hong Kong and Malaysia, as it has been reported in Thailand. With the recent improvement in economic status in Asia, it is probable that an increase in TBT usage will occur in aquaculture. Although contamination levels were generally low in mussel samples from most of the Asian developing countries, some of those from polluted areas in Hong Kong, India, Malaysia, the Philippines, and Thailand revealed levels comparable to those in developed nations. Furthermore, the concentrations of TBT in some mussels from polluted areas exceeded the threshold for toxic effects on organisms and estimated tolerable average residue levels as seafoods for human consumption. A significant correlation was observed between the concentrations of ΣBTs and ΣSn in mussels, and ΣBTs were made up mostly 100% of ΣSn in mussels taken from locations having intensive maritime/human activities. This suggests that anthropogenic BTs represent the major source of tin accumulation in mussels. To our knowledge, this is a first comprehensive report on butyltin pollution monitoring in developing countries in the Asia-Pacific region. [ABSTRACT FROM AUTHOR]

The polymerization?depolymerization dynamics of actin is a key process in a variety of cellular functions. Many spectroscopic studies have been performed in solution, but studies on single actin filaments have just begun. Here, we show that the time course of polymerization of individual filaments consists of a polymerization phase and a subsequent steady-state phase. During the steady-state phase, a treadmilling process of elongation at the barbed end and shortening at the pointed end occurs, in which both components of the process proceed at approximately the same rate. The time correlation of length fluctuation of the filaments in the steady-state phase showed that the polymerization?depolymerization dynamics follow a diffusion (stochastic) process, which cannot be explained by simple association and dissociation of monomers at both ends of the filaments. [ABSTRACT FROM AUTHOR]

Underpotential deposition (UPD) of Zn2+ at Au(1 1 1) was studied in the phosphate solutions with and without halide ions (Cl−, Br−, and I−) by cyclic voltammetry and in situ STM for the evaluation of the anion adsorption induced on the Zn UPD. The order of the strength of anion adsorption induced on Zn UPD was found to be different from the order of specific adsorption strength of I−>Br−>Cl−>PO43−&ges;SO42− at an Au substrate electrode. This anomalous tendency of anion adsorption induced on UPD Zn at Au seems to be identical with the cases of sulfate and phosphate adsorption induced on UPD Zn at a Pt electrode in the presence of chloride, being confirmed by radiotracer method. Such anomalous phosphate adsorption induced on Zn UPD was found to take place at Au(1 1 1) not only in the presence of chloride or bromide, but also even in the presence of iodide in the phosphate solution. The in situ STM images of Zn UPD were observed at Au(1 1 1) in the phosphate solution with iodide ions. At −200 mV (saturated calomel electrode; SCE) where the iodide adsorbs at substrate Au(1 1 1), the STM image was c(p×√ of 3R30°), and in the Zn UPD region, the STM image became (3×3R30°), and in the Zn UPD region, the STM image became (√ of 3×3×√ of 3)R30°. The latter image is discussed to be assigned to the image in the absence of iodide, i.e., that the adsorbed anions induced at Zn UPD are phosphate species even in the solution containing iodide ions. [Copyright &y& Elsevier]

Grazing incidence angle in-plane X-ray diffraction (in-plane XRD) was applied to characterization of an organic–inorganic hybrid Langmuir–Blodgett (LB) film in a laboratory scale. The hybrid LB film consisted of octadecyl ammonium cation and sodium montmorillonite layers at Si(1 0 0) wafer. The in-plane XRD measurements of the hybrid LB film gave one diffraction peak at 20.0° (0.44 nm), which we assigned to the (1 1 0) and (0 2 0) reflections of montmorillonite. This was the first example of the in-plane diffraction from a single layered montmorillonite, presenting a clear evidence for the parallel orientation of the (0 0 1) plane with respect to a film surface. [Copyright &y& Elsevier]

Analyzes the levels of organochlorine and butyltin in myctophid fishes from the western North Pacific Ocean. Determination of contamination status, accumulation patterns and distribution of the compounds; Maximum concentration of the chemicals in the sampled fishes.

Insulin receptor substrates (IRSs) are well-known mediators of the insulin and insulin-like growth factor (IGF)-I signaling pathways. We previously reported that the protein levels of IRS-2, a molecular species of IRS, were upregulated in the livers of rats fed a protein-restricted diet. This study aimed to elucidate the physiological role of IRS-2, whose level increases in response to protein restriction in cultured hepatocyte models. Hepatocyte-derived cell lines subjected to amino acid deprivation showed increased IRS2 mRNA and IRS-2 protein levels due to increased IRS2 transcription and translation, respectively. Amino acid deprivation markedly increased vascular endothelial growth factor-D (VEGF-D) secretion. Remarkably, the amino acid deprivation-induced VEGF-D secretion was suppressed by IRS-2 knockdown and enhanced by IRS-2 overexpression. These results suggest that IRS-2 is an intercellular signaling molecule that extracellularly transmits information on amino acid deprivation stress by regulating the secretion of growth factors such as VEGF-D. Moreover, this function of IRS-2 is distinct from its currently accepted function as a mediator of the insulin/IGF-I signaling pathways. This study demonstrates that IRS-2 can modulate protein secretion in an insulin-independent manner and greatly expands our understanding of the role of IRS-2, which is upregulated in response to amino acid deprivation. [ABSTRACT FROM AUTHOR]

Determines the total concentration of total tin and butyltin compounds in the liver of cetaceans collected from Japanese coastal waters. Role of anthropogenic butyltins in the view of total tin accumulation in higher tropic organisms; Comparison of the total tin and butyltin concentration in coastal and offshore species.

Pancreatic cancer is the disease of gastrointestinal cancer with the poorest prognosis. At present, in addition to surgery, multimodality treatment combining a variety of therapeutic methods is used. We usually employ the following combination of surgery, radiotherapy and chemotherapy: D2 surgery with pylorus-preserving pancreatoduodenectomy (PPPD), intraoperative radiotherapy (IORT), and portal catheterization (PC) with fluorouracil as the chemotherapy. In this study, we made a historical comparison of PPPD and PD and obtained the following findings: (1) PPPD allows almost the same extent of D2 dissection as conventional PD, and achieves radical treatment without any problems; (2) suppression of local recurrence by IORT cannot be expected from the results of the comparison between the four approaches, i.e. surgery alone, surgery + IORT, surgery + PC and surgery + IORT + PC, and (3) the rate of liver metastasis in patients treated by PC was significantly low. [ABSTRACT FROM AUTHOR]

Determines the residue levels of butyltin compounds (BTs) and its degradation products in benthic deep-sea organisms collected from Suruga Bay, Pacific coast of Japan, pertaining to environmental science. Elucidation of the status of contamination on these products; Delineation accumulation characteristics of the products; Conclusions reached.

In two-dimensional digital filters with complex coefficients, design flexibility is gained and the filter order can be lowered as compared with real coefficient filters. On the other hand, in the signal theory, the concept of analytic signal is well known in connection with single side-band amplitude modulator, which can be implemented by using a bandpass filter or a 90-degree phase-difference network. The latter implementation, which uses all-pass networks, yields far better characteristics as compared with the former. The conventional fan filter with complex coefficients is designed by shifting one-dimensional low-pass digital filters with a cutoff frequency of 0.5 π on the real frequency axis and applying a variable a variable transformation. In contrast, we propose a new design method of fan filters with complex coefficients that combines the approach of the forementioned 90-degree phase-difference network for the single sideband amplitude modulation and the theory of complex coefficient filters; i.e., two all-pass networks with 90-degree phase-difference are used in the new fan filters. [ABSTRACT FROM AUTHOR]

In designing a two-dimensional digital filter with special consideration of the phase characteristics, particularly the group delay characteristics, a very high-order filter is generally required. This paper extends the coefficients of the filter from real to complex and describes a design technique for comparatively low-order, two-dimensional, circularly symmetric filters with consideration of phase characteristics. First, the method of transforming a two-dimensional input signal into an analytic signal is described and then the design technique of two kinds of complex coefficient filters which use the properties of analytic signals is discussed. In the first kind variable transformation to a 1-D real coefficient FIR filter is used to obtain a 2-D has the merits of permitting independent setting of the sharpness of cutoff characteristics and circular symmetry. In the other kind of complex coefficient filter a recursive digital filter is obtained by using an all-pole filter having constant group delay in the passband of the transfer function and having a 2-D complex coefficient mirror image polynomial. It always then values of the coefficients and the overall group delay is also constants. Moreover, in this paper, design examples based on these methods are given and the validity of our methods is shown. [ABSTRACT FROM AUTHOR]

In the field of one-dimensional signal processing, the concept of analytic signal has been introduced in order to yield a low-pass expression for band-pass-type signals. This analytic signal is obtained by adding the Hilbert transform of the real numbers as the imaginary part to the original signal. One important property of this signal is that its Fourier transform vanishes for negative frequencies, i.e., it "appears only in the positive frequency axis." This property is applied to the design of one-dimensional digital filters. In this paper, a signal processing algorithm using two-dimensional digital filters with complex coefficients is proposed. This is done by extending the concept of analytic signal to two dimensions; the processing uses the fact that its Fourier Transform "exists only in the right half-plane of the two-dimension frequencies plane" or, in the case of quadrantal symmetry, "only in the first quadrant of the two-dimension frequencies plant." Using this algorithm, the degree of freedom for the design of 2D filters is increased and closed design methods for circularly symmetric filters and various new fan filters are possible. Moreover, difficulties of presently known methods such as high-order requirements and limitations upon the cutoff frequency are greatly relaxed. [ABSTRACT FROM AUTHOR]

This paper proposes a method of constructing an RC active network to realize a voltage transfer function matrix without using an integrator. The method is based on the fact that an m-input system of multi-variable controllable canonical form can be decomposed into m subsystems of controllable canonical form using state feedback and input transformation. The required m-input p-output voltage transfer function matrix is constructed using m passive RC networks and (m + p) summers. The network has the following structure. The capacitor edge voltage of the passive RC network is taken out as the state variable, and the state differential equation is realized by the feedback through the input-side summers. The output equation is realized by the feedforward through the input-side summers. The output equation is realized by the feedforward through the output-side summers. The feature of the proposed method is that it is applicable to any proper rational transfer function matrix of any size, not only of the square form. Another feature is that the transfer function matrix can be realized with a fewer number of active elements. [ABSTRACT FROM AUTHOR]

This paper proposes a method of realizing arbitrary complex coefficient transfer functions with complex double resistively terminated lossless filters as the reference network for complex wave digital filters (CWDFs). For this purpose, the Darlington synthesis method, which is known for realizing arbitrary real coefficient transfer functions, is expanded into the complex domain. Furthermore, a new construction method for a digital adapter without a delay-free loop is presented. Finally, a complex coefficient transfer function using some realization method is constructed and the validity of the proposed method is confirmed. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 3, 80(2): 12–23, 1997 [ABSTRACT FROM AUTHOR]

This paper shows that two complex coefficient transfer functions can be realized by a single hypercomplex coefficient network, utilizing all four outputs of the hypercomplex network. The realization is considered for the case where the two arbitrary complex coefficient transfer functions do and do not have a common denominator. It is shown that the transfer functions can he realized by the hypercomplex coefficient network of the same order in the former case and by the hypercomplex coefficient network with the half-order in the latter case. The realization of the transfer functions with the common denominator is interesting, but the general method to derive the transfer functions is not known. From such a viewpoint, this paper proposes the discrete-type Kautz approximation with the positive frequency as the domain of approximation, including the optimal pole determination algorithm. By this approach, two complex coefficient transfer functions with an n-th-order common denominator are derived from the two 2n-th-order real or complex coefficient transfer functions. The method can be considered as one that simultaneously approximates the amplitude and the phase. The proposed approximation method is an approximation only for the positive frequency domain, and the property of the analytic signal that the negative frequency component is zero can be utilized. As a result, the method proposed in this paper has the advantages that the degree of freedom in the filter design is enhanced and the sampling frequency can be halved. In addition, the network structure can be simplified. [ABSTRACT FROM AUTHOR]

This paper considers the complex coefficient transfer function with transmission zeros on the imaginary axis and presents a method to realize such a transfer function by a reactance network including imaginary resistors with double resistor termination. Using the obtained network and the reference network for the complex-wave digital filter, the complex digital filter with transmission zeros on the imaginary axis can easily be extended, which is important in practice. In this paper, Brune's method modified by Belevitch as well as Fujisawa's method extended by Morimoto et. al. are improved and the realizability condition is relaxed. Then, several construction examples are shown an the features of construction methods are compared and discussed. [ABSTRACT FROM AUTHOR]

Exact estimation of frequencies of sinusoidal signals corrupted by noise is an important problem in a variety of areas, and various kinds of methods for the solution of this problem have been proposed. Among these methods, the adaptive spectral estimation method, which processes data recursively, needs consideration of the convergence property of the adaptive filter as well as the precision of the spectral estimation. in this paper, we propose a method which improves the technique of analytic signal processing used to improve estimation precision slowing the convergence speed of the adaptive filters. This method makes good use of the data discarded by decimation and processes two series of the same statistics in parallel. By this operation, the number of times the coefficients are updated in the adaptive filter is doubled and, therefore, the rate of convergence is much improved. Furthermore, by increasing the number of data by interpolation of the observed data, faster convergence speed than that of the conventional method is realized. This method has an advantage of simple structure. It can be also easily applied to other adaptive filtering using subband filters. [ABSTRACT FROM AUTHOR]

This paper proposes an extension of the real-coefficient wave digital filter by Fettweis et al. (WDF) to the complex-coefficient WDF (CWDF) as well as a construction method to realize an arbitrary complex-coefficient transfer function. The first step of the proposed construction method is to synthesize the lossless reactance circuit containing the imaginary resistors (except for the input terminal) as an analog reference circuit by the continued-fraction expansion. In this study, the LC ladder network containing imaginary resistors is synthesized as the reference network, realizing the denominator polynomial of the transfer function. Then the state-variable representation is constructed and the numerator polynomial is realized by determining the tap coefficients to the external output, using the transform matrix. In this process, the reference network is transformed into WCDF, end the tap is formed considering the relation between incident/reflected waves and the terminal voltages. By this procedure, the required transfer function can be realized. Finally, the proposed method is compared to other construction methods and the low-sensitivity property of the proposed method is demonstrated. [ABSTRACT FROM AUTHOR]

A new design method for two-dimensional allpass filters to approximate the desired phase characteristic is proposed in this paper. Considering the denominator polynomial of the allpass transfer function, the design method via Hilbert transform is expanded to a two-dimensional ease with complex coefficients. When the Hilbert transform is used, a problem arises in that sometimes truncating coefficients cause the filter to be unstable. In this paper, in an unstable ease, the resultant frequency response is approximated as a low-order polynomial by using the Lagrange interpolation technique and the same procedures are repeated. Therefore, this proposed method ensures the stability of the designed filter because the coefficients of order higher than the desired order are small enough to be almost zero. [ABSTRACT FROM AUTHOR]

This paper considers digital filters with hypercomplex coefficients. Filters of this type can reduce the order of filters to one-fourth the one with real coefficients. It is reported that the first-order digital filter with hypercomplex coefficients can realize the fourth-order digital filter with real coefficients which can be expressed by a second-order all-pass filter with complex coefficients. This paper considers also generalization including the foregoing special case and shows that the first-order digital filter with hypercomplex coefficients can realize an arbitrary-order digital filter with real coefficients less than 4. Arbitrary higher-order digital filter with real coefficients can be realized by parallel connection or cascade connection of first-order digital filters with hypercomplex coefficients. This paper considers the following three different realizations: (a) realization by parallel connection: (b) realization by cascade connection of real part; and (c) realization by cascade connection. We find that case (b) is the most low sensitive. Finally, stability criteria of hypercomplex digital filters of first-order are suggested. [ABSTRACT FROM AUTHOR]

Filter banks are being used in many areas, e.g., voice processing in communication systems; and active research has been on-going in this field in recent years. This paper describes a method of realizing multi-channel IIR filter banks which could divide the frequency range into an arbitrary number of uniform bands. In this method, filter banks are formed by shifting the low-pass characteristics with the help of variable transformation with respect to ω and a π/2 phase shifting with the help of a Hilbert transformer. Hence, this design procedure becomes similar to the design of linear-phase all-pass filters. This IIR filter including the Hilbert transformer can be implemented with the help of an all-pass filter, and thus low coefficient sensitivity property can be realized. Moreover, the transition band is narrower compared to the FIR structure. Other than the forementioned merits, the design is comparatively simple; and all the coefficients can be obtained in an analytical way using Fourier series expansion. [ABSTRACT FROM AUTHOR]

Several methods have been presented recently for constructing the one-dimensional IIR digital filter by combining all-pass networks. It is known that the filter composed of the all-pass networks has a better computational efficiency and also low coefficient sensitivity due to the structural boundaries. In addition to the one-dimensional filters, a construction of the two-dimensional filter based on the all-pass network has also been proposed. A problem in that method, however, is the restriction on the realizable characteristics. This paper attempts to overcome that problem, and proposes a new construction of the two-dimensional digital filter using the all-pass network. The new approach employs the complex coefficient all-pass network instead of the conventional real-coefficient all-pass network. By this approach, the degree of freedom in the design is enhanced, and the characteristics which have been difficult or impossible to realize in the case of the real coefficient filters, are now made realizable. [ABSTRACT FROM AUTHOR]

This paper proposes a new design method for the filter bank. The filter bank is a system which can reconstruct a signal via band-splitting, decimation, interpolation and restoration. It is employed widely to solve various problems in the communication system, and various methods have been presented for its specification, implementation and design. This paper discusses the approximate realization of the filter bank, which is called the M-channel uniform-splitting FIR perfect-reconstruction filter bank, and its design principle is as follows. First, the analysis filter is designed so that each channel has the characteristic which is the translation of the given LPF on the frequency axis. Then the synthesis filter is designed in the time-domain so that the unit impulse response of the whole system is equivalent to the unit pulse, i.e., that the response of the linear-phase all-pass transmission characteristic. The Hilbert transformer plays the important role in the translation of the characteristic. Compared with the conventional design, the proposed method has the merit that no constraint is imposed on the band splitting and the band is partitioned uniformly with an arbitrary number of divisions. Design examples are shown to indicate the usefulness of the proposed design. [ABSTRACT FROM AUTHOR]

This paper considers first, for the purpose of estimating the frequency of sinusoids corrupted by noise, a spectral estimation method employing the analytic signal, and proposes an analytical signal pre-filtering technique for that estimation method. Also, it is shown that the analytic signal processing in spectral estimation gives rise to reduction in the estimation variance, Next, the spectral estimation method with complex-coefficient bandpass filters is considered and a method with complex-coefficient filter bank is developed which could analyze the entire frequency region which contains any simusoids to be estimated. This method with filter bank could resolve a problem found in the conventional method with decimation techniques. Furthermore, an algorithm is obtained which could provide considerably more accurate estimation results than the conventional one. This algorithm effectively employs the signals remaining in the sampling operation of decimation, and then averages then. [ABSTRACT FROM AUTHOR]

This paper proposes a linear prediction method using the analytic signal which occupies half the bandwidth of the real signal. Consequently, the order is halved in the proposed method, thereby reducing drastically the computational complexity. The proposed method gives a stable solution for a finite word-length operation, and the obtained reflection coefficient has a low coefficient sensitivity. These are both useful properties in the synthesis of speech. [ABSTRACT FROM AUTHOR]

This paper describes a new method for designing two-dimensional (2-D) digital filters with complex coefficients having circularly symmetric and fan characteristics by applying variable transformation (spectral variable) to one-dimensional (l-D) IIR digital filters with complex coefficients. A 2-D digital filter with complex coefficients has an advantage in that it can increase greatly the degree of freedom for design, since once it satisfies the design specification partly in the frequency plane, its characteristics can be arbitrary in other regions. Here, a design method is proposed which makes positive use of this property of the complex coefficient digital filters. Since we have introduced the complex coefficient filters into spectral transformation functions and 1-D prototype filters, there is no constraint on cutoff frequency (radius) accomplishable in circularly symmetric filters. In fan filters even a characteristic that has been difficult to design unless one uses optimization techniques, has become easy to design by means of variable transformation without using any optimization techniques. Moreover, the stability of the resulting IIR filters is guaranteed in simple conditions. [ABSTRACT FROM AUTHOR]

This paper shows that by taking every M th impulse response from the impulse respons- es of FIR low-pass digital filters and constructing a new digital filter based on them. a filter is obtained with low-pass characteristic such that the passband width is N times that of the original filter. Next, taking advantage of this characteristic, a method is proposed for designing a low-pass digital filters with variable cutoff frequency based on the same circuit by first designing a basic digital filter and varying 14, that is, changing over taps. This principle is applicable not only to FIR filters but similarly also to HR filters if some restrictions are allowed for denominator polynomials. Further, it is shown that by applying this theory to IFIR (Interpolated FIR) digital filters and multi rate digital filters, filters can be realized which are more effective with respect to their cutoff characteristic and operational points. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) filter banks are used in subband coding of images, and are systems which split a signal into the narrow bands and/or resynthesize it. This paper presents a method of constructing 2D filter banks using 2D prefilter and 2D polyphase filter banks. First, the input signal is divided into four kinds of band art the 2D plane by 2D prefilter with IFIR (Interpolated FIR) transfer function. Then the 20 prefilter is designed so that the four kinds of band become 1. These resulting output signals are band-split separately and synthesized by 2D DFT polyphase filter banks. Hence, its design method becomes very simple and both the required order and the number of multiplications can be reduced. [ABSTRACT FROM AUTHOR]

This paper discusses the extension and generalization of McClellan transformation, which is one of the most powerful design methods for two-dimensional (2-D) FIR digital filters, to the multidimensional complex-coefficient FIR digital filter. As the first step, the multidimensional (N-D) analytic signal for the actual signal processing is introduced. Then, the N-D complex-coefficient McClellan transformation is proposed, together with the design method for N-D filters. For the characteristics which are symmetrical in regard to the hyperplane ωi-0 (i-1~N), the N-D analytic signal is used with the frequency components only in the positive ranges of to Then, it suffices to satisfy the filter specifications only in that frequency region, with the characteristics in other regions being arbitrary. In the complex-coefficient McClellan transformation, the complex-coefficient 1-D FIR filter can be used as the fundamental unit, in contrast to the real-coefficient case. This increases the degree of freedom in the filter design, realizing, in general, better characteristics with lower-order transfer functions. Another merit is that the design is simple since the transformation of the variable is employed. As an example, 3-D fan-filter is designed using complex- and real-coefficient McClellan transformations, and the realized characteristics are compared. [ABSTRACT FROM AUTHOR]

Comprehensive and updated information about polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) in surface sediments from Hanoi, the capital city of Vietnam, is rather scarce. In this study, concentrations and profiles of 209 PCBs, 41 polybrominated diphenyl ethers (PBDEs), 2,2′,4,4′,5,5′-hexabromobiphenyl (BB-153), hexabromocyclododecane (HBCD), pentabromoethylbenzene (PBEB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and decabromodiphenyl ethane (DBDPE) were determined in sediment samples collected from the Red River and some inner-city rivers of Hanoi. Concentrations (ng/g dry weight, median and range) of pollutants decreased in the order: DBDPE (28; not detected ND – 59) ≈ PCBs (27; 1.7–50) > PBDEs (23; 0.20–61) > HBCD (1.2; ND – 5.2) > BTBPE (0.46; ND – 3.6) > BB-153 (0.004; ND – 0.014) > PBEB (ND). Pollutant levels in the inner-city river sediments were about one to two orders of magnitude higher than those measured in the Red River main stream sediments. Tri-to hexa-CBs are major homologs but detailed profiles vary between individual samples, reflecting source and/or seasonal variations. CB-11 and CB-209 were found at higher proportions in sediments than in technical PCB mixtures, suggesting their novel sources from pigments. Deca-BDE and DBDPE are the most predominant BFRs with an increasing trend predicted for DBDPE. A preliminary ecological risk assessment was conducted for these pollutants in sediments. Total PCBs and deca-BDE in a few inner-city river sediments may exhibit adverse effects on benthic organisms, but no serious risk was estimated in general. • Detailed profiles of PCBs and BFRs were examined in urban surface sediments. • CB-11 was among the most predominant congeners, accounting for 7 ± 4% of ΣPCBs. • Elevated proportions of CB-209 were found in inner-city river sediments (0.12–2.6%). • BFR levels decreased in the order: DBDPE > PBDEs > HBCD > BTBPE > BB-153. • PCBs and deca-BDE are likely to pose greater ecological risk than other BFRs. [ABSTRACT FROM AUTHOR]

Contamination levels and profiles of mono- to deca-chlorinated biphenyls (PCBs) were characterized in a sediment core dated in 1954–2011 from Beppu Bay, southwestern Japan, providing a comprehensive and detailed picture on the environmental occurrence, temporal trends, and emission sources of these pollutants in the study area. Concentrations of total PCBs in the core ranged from 3.5 to 150 (median 15) ng g−1 dry weight and exhibited depth profile matching with Japanese PCB production and emission patterns (i.e., drastically increasing from the early 1960s, peaking in 1970, and then rapidly decreasing). Origin of PCBs in the studied samples largely associated with Kanechlor mixtures (e.g., KC-300 and KC-400), especially for sediment layers dated between the mid-1960s and early 1970s (i.e., the intensive PCB production period in Japan). In addition, dechlorination and weathering signals and emerging inputs of PCBs were also observed in deeper and shallower sediment segments with notable proportions of some unique congeners such as CB-47/48/51 and CB-11, respectively. Historical fluxes of PCBs in our samples showed quite similar vertical shape as concentrations. In the context of national implementation for complete treatment of PCB-containing waste until 2024, further investigations on spatiotemporal trends and environmental loads of PCBs in Japan are necessary. Unlabelled Image • Mono- to deca-CBs were measured in a sediment core from Beppu Bay, Japan. • Depth profiles of total PCBs exhibited Japanese PCB production history (peaks in 1970). • Kanechlor mixtures (notably KC-300 and 400) were major PCB sources in 1960s–1970s. • Partial dechlorination signals were observed with abundance of CB-47/48/51 in 1950s. • The occurrence of mono-CBs, CB-11, and CB-209 may reflect novel sources. [ABSTRACT FROM AUTHOR]