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Anomalous local structure and magnetic moment of an inhomogeneous FeSe based superconductor indicating importance of the structure and magnetic correlations in these materials.

The effect of K substitution for Ca in Bi2Ca2-xKxCo2Oy (x = 0.0, 0.05, 0.075, 0.10, and 0.125) thermoelectric ceramics, produced via laser floating zone (LFZ) method, have been systematically investigated. XRD patterns are quite similar for all samples and main peaks in the patterns correspond to reflection planes of the thermoelectric phase together with small amount of secondary phases. SEM micrographs revealed well oriented grains along the growth direction, and the presence of three different contrasts, associated through EDS to different phases, namely, black (Co oxide), white (Bi poor phase) and grey (Bi2Ca2Co1.7Oy TE phase). It was also seen that the amount of secondary phases diminishes with K-increase. The room-temperature resistivity values sharply decrease from 0.75 mΩ.m for the undoped sample to 0.44 mΩ.m for the 0.05 K-doped one, increasing for higher doping. Seebeck coefficient also decreases from 190 μV K−1 in the pristine sample, to 160 μV K−1 in all the K-doped ones, at 390 K. Thermal conductivity increases with temperature up to around 250 K, decreasing at higher temperatures. Thermal conductivity at 390 K decreases from 1.1 W K−1 m−1 in the pristine sample to lower values by K-doping, reaching the minimum, 0.9 W K−1 m−1, in the 0.125 K-doped one. As a result, the highest ZT value of has been determined in 0.05 K-doped sample, around 0.021 at 390 K., This study was carried out within the scope of Cukurova University Scientific Research Projects Unit FBA-202114163, FBA-2020-12784, FBA-2022-14414. The authors wish to thank the Spanish MINECO-FEDER (MAT2017-82183-C3-1-R), and Gobierno de Aragón (Research Group T54-20R) for funding.

We have studied the local structure of layered Eu(La,Ce)FBiS2 compounds by Bi L3-edge extended X-ray absorption fine structure (EXAFS) measurements as a function of temperature. We find that the BiS2 sub-lattice is largely distorted in EuFBiS2, characterized by two different in-plane Bi-S1 distances. The distortion is marginally affected by partial substitutions of Ce (Eu0.5Ce0.5FBiS2) and La (Eu0.5La0.5FBiS2). The temperature dependence of the local structure distortion reveals an indication of possible charge density wave like instability in the pristine self-doped EuFBiS2 and Ce substituted Eu0.5Ce0.5FBiS2 while it is suppressed in La substituted Eu0.5La0.5FBiS2. In compounds with higher superconducting transition temperature, the axial Bi-S2 bond distance is elongated and the related bond stiffness decreased, suggesting some important role of this in the charge transfer mechanism for self-doping in the active BiS2-layer. In-plane Bi-S1 distances are generally softer than the axial Bi-S2 distance and they suffer further softening by the substitutions. The results are discussed in relation to an important role of the Bi defect chemistry driven asymmetric local environment in the physical properties of these materials.

NaSn

Isovalent substitution of S by Se in LaOBiS

Recently CeOBiS2 system without any fluorine doping is found to show superconductivity posing question on its origin. Using space resolved ARPES we have found a metallic phase embedded in the morphological defects and at the sample edges of stoichiometric CeOBiS2. While bulk of the sample is semiconducting, the embedded metallic phase is characterized by the usual electron pocket at X point, similar to the Fermi surface of doped BiS2-based superconductors. Typical size of the observed metallic domain is larger than the superconducting correlation length of the system suggesting that the observed superconductivity in undoped CeOBiS2 might be due to this embedded metallic phase at the defects. The results also suggest a possible way to develop new systems by manipulation of the defects in these chalcogenides with structural instability.

The purpose of this study is to evaluate the real-time respiratory motion of the prostate and surrounding tissues/organs in the supine and prone positions and to investigate, using cine-MRI, whether a belly board can reduce respiratory-induced motion in the prone position. Cine-MRI scans were made of 13 volunteers in the supine and prone positions on a flat board and in two different prone positions using a belly board. Images in cine mode were recorded for 20 seconds. For each session, the points of interest (POIs) were located at the apex, base, mid-anterior surface and mid-posterior surface of the prostate; the tip of the seminal vesicle; the pubic symphysis; and the sacrum. The maximum range and standard deviation (SD) of the displacement from the mean value were calculated. The SDs for each of the four different positions were compared using a paired t-test. Respiratory-induced prostate motion was significantly larger in the prone position than in the supine position. However, when a belly board was used in the prone position, motion in the prostate and surrounding tissues/organs was significantly reduced. There were no significant differences between the two different positions using a belly board in any of the POIs.

In real residual chlorine management practices, a simple criterion is required for evaluating chlorine consumption by inner wall surfaces of water distribution pipes. The amount of chlorine consumed by 1 m2 of the inner wall surface of a pipe per hour (J-value) can be used for this purpose. To estimate the J-value for a pipe, a zero-order rate equation was adopted for chlorine reduction caused by a pipe wall, based on laboratory experimental results. The J-value was closely related to characteristics of the pipe material. The J-value for old unlined metallic pipes was extremely large (J > 18 mg m−2 h−1), whereas that for plastic polymer pipes was very small (J < 0.08 mg m−2 h−1). The J-value for cement mortar lined pipes increased exponentially with increasing water temperature. This paper proposes an effective method on the basis of J-value for residual chlorine management practices. First, this method is used to identify those pipes which consume relatively more chlorine than other pipes. Maximum allowable residence time (MART), within which the required minimum chlorine concentration can be maintained, can also be estimated by this method. MART is useful to determine necessary and sufficient measures for shortening water residence time in identified pipes.

The behaviour of residual chlorine concentration in drinking water treated by the mid-chlorination or the advanced water treatment (AWT) was investigated. The AWT removes dissolved organic matter more than the mid-chlorination, thus the rate of residual chlorine reduction is decreased. The analysis of chlorine concentration data measured by automated continuous monitoring devices revealed that the introduction of AWT reduced the maximum and mean chlorine concentration by 0.33 mg L−1 and 0.21 mg L−1 compared to the mid-chlorination respectively, while the minimum concentration was maintained at around 0.3 mg L−1 in the whole city. The overall chlorine reduction rate coefficient in the AWT was reduced to approximately half of that in the mid-chlorination. Volatilization of chlorine from a water surface could be expressed by the zero-order rate of reaction from laboratory experiments. The rate of volatilization increases with increasing water temperature and shallower water depth. The residual chlorine prediction models were developed based on the results of data monitoring and laboratory experiments. The accuracy of simulated values is good and almost all of the predicted concentrations are in the range of±0.1 mg L−1 of measured concentrations. The models are very effective to control residual chlorine concentration at predetermined target value.

The lentiviral vector is a promising tool for human gene therapy because of its ability to transduce genes into many cell types. However, one of the technical problems associated with the lentiviral vector is that lentiviral titers in current production systems are relatively low compared with the other viral vectors. In this study, we provide genetic evidence that the attachment of heterologous myristoylation (myr) signals on the amino-terminus of human immunodeficiency virus type 1 Pr55(Gag) (Gag) can increase the viral yield up to 10-fold, leading to the enhancement of gene transduction in many cell lines. The myr signal Gag constructs behaved similarly to the wild-type Gag in targeting to detergent-resistant membrane compartments, Vps4-dependence for viral budding, and virion morphology. However, the myr signal Gag constructs showed improved oligomerization efficiency as measured by bioluminescence resonance energy transfer in living cells, contributing to increased viral production and efficient activation of the viral protease responsible for virion maturation. The genetically modified Gag represents the next generation lentiviral vector, and should contribute to the success of many lentiviral vector applications.

We have performed high-resolution angle-resolved photoemission spectroscopy on hole-doped high- T c cuprate superconductors (HTSCs) to study many-body interaction and the universality of low-energy excitation gap. In Bi 2 Sr 2 CaCu 2 O 8 (Bi2212), we observed a kink in the dispersion in the off-nodal region in the superconducting state, which remarkably weakens on impurity substitution. We also find that the appearance of the kink in the off-nodal region is a common feature of Bi2212 and La 1.85 Sr 0.15 CuO 4 (LSCO), while the energy scale is remarkably different between two compounds (70 and 20 meV). We discuss universality of the kink in dispersion in the hole-doped HTSCs in terms of the coupling of electrons with spin fluctuations.

This paper presents an advanced control system in a tilting ladle type automatic pouring system. To improve the productivity and save energy, in the pouring process, it is important that the mould be filled precisely and quickly with molten metal. A sequence control employing prediction of filling weight is proposed in this paper. In the proposed control system, the sequence parameter varies depending on the predicted filling weight during the back tilting. The proposed control system has an advantage in that it can be performed by common control equipment such as a programmable logical controller. The effectiveness of the proposed filling weight control system is demonstrated through the experiments using water.

We have performed systematic ultrahigh-resolution photoemission spectroscopy on the iron-based superconductor LaFeAsO 1- x F x ( x =0-14%) to elucidate the evolution of electronic states with doping. We found that the density of states (DOS) around the Fermi level of the superconducting sample is markedly smaller than that of the undoped sample in contrast to conventional phonon-mediated superconductors. We observed a pseudogap in the DOS above the superconducting transition temperature ( T c ) which opens/closes at a temperature ( T * ) well above T c . The energy scale of pseudogap and the T * value are gradually reduced upon fluorine substitution. The origin of pseudogap is discussed in terms of the partial nesting of Fermi surfaces due to the spin-density-wave formation or the short-range spin correlations.

We report angle-resolved photoemission spectroscopy on optimally doped high- T c superconductor La 1.85 Sr 0.15 CuO 4 ( T c = 37 K) to elucidate the character of low-energy excitations in the superconducting state. We find a clear evidence for the emergence of a sharp superconducting quasiparticle peak below T c together with opening of a superconducting gap at off-nodal region, while no signature of a quasiparticle peak is observed at (π, 0). From the comparison of spectral lineshape and energy dispersion between the nodal and the off-nodal region, we conclude that there are two characteristic energy scales (70 and 20 meV) in the superconducting state of optimally doped La 1.85 Sr 0.15 CuO 4 .

We report high-resolution angle-resolved photoemission spectroscopy on electron-doped cuprate Nd2-xCexCuO4 to study the quasiparticle (QP) state in the vicinity of the Fermi level. Measurements of momentum dependence have revealed that the mass-renormaliz

Systematic angle-resolved photoemission spectroscopy (ARPES) has been performed on Bi2Sr2Can-1CunO2n+4 (n = 1-3). For n = 2 and 3, the dispersion kink becomes pronounced on approaching (pi, 0) below T-c, while a kink appears only around the nodal directio

Despite years of intensive research on copper oxide superconductors with high transition temperatures (T-c), the driving force of superconductivity has not yet been clarified. Angle-resolved photoemission spectroscopy (ARPES)(1-3) measurements have uncove

High-resolution angle-resolved photoemission spectroscopy (ARPES) has been performed on Nb1−xTixXc2 (Xc = S, Se, Te) to elucidate the change in the band structure as a function of x and Xc. We found that spectral intensity near E F of S- and Se-based compounds is remarkably suppressed, suggesting the strong scattering of electrons by the substitution of transition metals. In contrast, Te-based compound shows a clear Fermi edge. We discuss the origin of metal–semiconductor transition in terms of the strength of hybridization between chalcogen p band and transition metal d band.

We have performed high-resolution angle-resolved photoemission spectroscopy (ARPES) with synchrotron radiation on layered transition-metal dichalcogenide 1 T -VSe 2 to study the mechanism of the three-dimensional charge-density-wave (CDW) transition. We found that the Fermi surface around the M(L) and K(H) points shows considerable wiggling along the wave vector normal to the layer ( k z ) despite the apparently two-dimensional crystal structure. ARPES spectra below the CDW transition temperature show a signature of pseudogap opening at a specific k z -region on the Fermi surface, demonstrating that the CDW transition of 1 T -VSe 2 is driven by three-dimensional Fermi-surface nesting.

We have performed systematic high-resolution angle-resolved photoemission spectroscopy (ARPES) on layered transition-metal dichalcogenides Nb1−xTixXc2 (Xc = S, Se, Te) to study the mechanism of metal–semiconductor transition as a function of x and Xc. We found a pseudogap near EF in the S- and Se-based compounds while a clear Fermi edge is observed in the Te-based compound. The existence of the pseudogap indicates the strong scattering of electrons by the random potential caused by substitution, which prevents formation of the charge density wave and at the same time decreases the metallic conductivity. The metallic character of Nb1−xTixTe2 is explained in terms of the relatively strong Te 5p–Nb 4d (Ti 3d) hybridization near EF.

We have performed a high-resolution angle-resolved photoemission spectroscopy (ARPES) on high- T c superconductors (HTSCs) Bi 2 Sr 2 Ca n -1 Cu n O 2 n +4 ( n =1–3) to study the systematics of the electronic structure and the origin of many-body interactions responsible for superconductivity. We find that a large hole-like Fermi surface and d-wave superconducting gap are generic features of Bi-based HTSCs. For n =2 and 3, a sudden change in the energy dispersion, so-called “kink”, becomes pronounced on approaching (π,0) in the superconducting state, while a kink appears only around the nodal direction in the normal state. The kink around (π,0) disappears at T c . For n =1, the kink shows no significant temperature dependence even across T c . This could suggest that the coupling of electrons with Q =(π,π) magnetic mode is dominant in the superconducting state for multi-layered cuprates, while the interaction at the normal state and that of single-layered cuprates have a different origin.

The presence of tumor infiltrating lymphocytes (TIL) has been attributed to the host cell mediated immune response against the evolving malignancy. However, due to specific evasive and escape mechanisms, the immune competent cells are rendered ineffective. One such mechanism may be the production of immune suppressor substance(s), inhibiting lymphocyte proliferation, and subsequently, their transformation into effector cells. To evaluate a possible impact of RCC extract on lectin and alloantigen-induced proliferation of TIL and peripheral blood lymphocytes (PBL) from renal cell carcinoma (RCC) patients and from healthy control human subjects. Tumor extract and TIL were derived from 13 patients with RCC undergoing radical nephrectomy. Tumor infiltrating lymphocytes and PBL from these patients were activated with Concanavalin A (Con-A), Phytohemoglutinine (PHA) or Pokeweed (PW) and the rate of blastogenesis was measured by (3)H Thymidine incorporation. The same procedure was used in assay with PBL from control healthy blood donors. There was a significant reduction (88.6%) in the proliferative response to ConA of TIL compared to PBL from the same patients (P = 0.007). A similar decrease was seen following stimulation by PHA (85.8%, P = 0.01) and PW mitogen (78.5%, P = 0.001). A 79.5% decrease in response level of TIL to alloantigens compared to PBL from RCC patients (P = 0.021), was observed. Lectin induced proliferative response of RCC patients was significantly lower in the presence of RCC extract (82.9%) compared to normal kidney extract (P = 0.008). Alloantigenic stimulation of healthy individual PBL was also decreased significantly in the presence of RCC extract (92.9%, P = 0.0001) compared to normal kidney extract. Similarly, lectin induced stimulation of healthy control PBL in the presence of RCC extract was significantly lower (83.2%, P = 0.003). Our data suggest that RCC extract contains an immune suppressive substance(s), capable of inhibiting lymphocyte proliferative response of tumor infiltrating lymphocytes as well as of PBL from patients and healthy individuals alike. This may be one of the mechanisms by which the tumor evades the transformation of lymphocytes into effector killer cells, and thus affects the biological inter-relationship between tumor and host. Identification of this substance and its gene may provide an effective anti-tumoral treatment modality.

An omnidirectional wheelchair is highly maneuverable in narrow or crowded areas such as residences, offices and hospitals. In this paper, a novel motion control system for an omnidirectional wheelchair is proposed. In order to ensure a comfortable ride for the patient, the controller is designed using a hybrid shape approach that considers both time and frequency characteristics. The effectiveness of the proposed system is evaluated by the output signal of a sensor attached to the wheelchair and by a descriptive inspection by several users.

We have performed ultrahigh-resolution angle-resolved photoemission spectroscopy of (Bi,Pb)2Sr2CuO6 by using a newly developed xenon-plasma light source to clarify the origin of the pseudogap (PG). We determined the comprehensive momentum and temperature dependences of the superconducting (SC) gap and the PG, and revealed a smooth evolution of the PG from the SC gap. We also found a linear scaling behavior of the characteristic PG temperature with the SC gap size regardless of the momentum location. These experimental results strongly suggest that the observed PG is caused by the precursor pairing.

We report results of angle-resolved photoemission spectroscopy on a heavily electron-doped BaFe2−xCoxAs2. By using synchrotron-radiation light, we have investigated the band dispersion near the Fermi level ( E F ) of BaFe2−xCoxAs2 (x = 0.3) for different wave vectors perpendicular to the crystal surface ( k z ) . We find that observed holelike band does not cross E F around Γ or Z point of the Brillouin zone, unlike the optimally- or under-doped samples. The holelike band also shows a finite k z dispersion of about 20 meV. These results indicate that the coexistence of hole and electron pockets connected by the antiferromagnetic wave vector plays an important role to the mechanism of superconductivity.

We have performed high-resolution angle-resolved photoemission spectroscopy of an electron-doped iron-based superconductor BaFe 1.85 Co 0.15 As 2 , and experimentally determined the Fermi-surface, the band structure and the superconducting gap. We found an isotropic s -wave-like superconducting gap on a hole pocket centered at the Γ point and on electron pockets at the M point. The superconducting gap magnitude is significantly enhanced on the Fermi-surfaces connected by the antiferromagnetic wave vector, suggesting the importance of an interband interaction on the pairing mechanism.

With the development of /spl plusmn/250 kV DC-XLPE power cable and flexible joint so far, there arose a need to develop other components for the construction of DC-power transmission. One of those is SF/sub 6/-gas type, horizontally installed termination. To supply the DC electric power with reliability and stability, we need to clarify the phenomena under DC voltage application in this system. This paper examines the flash-over (FO) phenomena under DC voltage application in the SF/sub 6/-gas type, horizontally installed termination by using the model electrode in which the firefly of metal particle was imitated under the condition of charge accumulation on the epoxy bushing. In this examination, we confirmed experimentally that the behavior of metal particles was affected by the change of a field distribution due to the charge accumulation on the epoxy bushing, on the other hand, the metal particle promoted the charge accumulation on the epoxy bushing. Under these circumstances, FO initiated at the edge of the metal particle showing firefly, developed along the epoxy bushing surface. These seemed to mean that there was a synergetic effect of charges accumulation and behaviors of metal particle to introduce a FO. It was concluded that it was very important to be strongly aware of the existence of metal particles and its behavior in the SF/sub 6/-gas type termination, when it was used under DC voltage application.

Odor produced by breakpoint chlorination in a drinking water purification process was researched. Ammonia and six amino acids (glycine, alanine, valine, leucine, arginine, proline) were chlorinated and production of odor and its change were investigated. An intense odor which was different to the odor of residual free chlorine was detected after the chlorination of ammonia. The production of the odor was affected by pH and chlorine dose rate. While the intense odor was not produced in the breakpoint chlorination at pH 8.3, a weak odor before the breakpoint and the intense odor after the breakpoint were produced at pH 6.5. At pH 3.0, the intense odor was detected even in a sample of low chlorine dose rate. An identification of the intense odor substance was done using a gas chromatograph-mass spectrometer and trichloramine or a dimer of dichloramine was suspected as the odor causing substance. In chlorination of the six amino acids, the intense odor and its change were different according to each amino acid. Production of chlorinated intermediate and final products which had a different odor were suspected as one of the reasons.

Long range optical fiber sensors for power cable maintenance have been incorporated into a newly developed 500 kV DC submarine power cable. Optical fibers are used for a distributed temperature sensor and a mechanical damage sensor. The distributed temperature sensor provides data on temperature at distances up to 30 km, and the mechanical damage sensor locates external damage points on the submarine cable. After each characteristic was investigated, optical fiber sensors were incorporated on the submarine power cable. This composite cable was evaluated by various mechanical tests. The results were satisfactory and showed the composite cable to be of practical use. This new approach of incorporating optical fiber sensors in the cable structure brings a new sophistication and reliability to cable maintenance.

We studied the impurity effect on the electronic structure near the Fermi level in Bi 2 Sr 2 CaCu 2 O 8+ δ by high-resolution angle-resolved photoemission spectroscopy to clarify the origin of dispersion kink in high- T c superconductors. We found that the dispersion kink at off-nodal region is significantly suppressed by Zn or Ni impurity while that at the node is less affected, suggesting that electrons are strongly coupled to the spin excitations at the off-nodal region.

Systemic lupus erythematosus (SLE), which spontaneously develops in (NZB (New Zealand Black) × NZW (New Zealand White)) F1 mice, is strictly dependent on CD4+ T cells. We found that in these mice with overt SLE, CD4+ T cells expressing CD69 molecules, an early activation Ag, are dramatically increased in peripheral lymphoid tissues and inflammatory infiltrates in the kidney and lung, but not in peripheral blood, while CD8+ and NK1.1+ T cells were virtually CD69−. Various adhesion molecules, including LFA-1, ICAM-1, CD43, CD44, P-selectin, and E-selectin, were up-regulated. Analysis of the TCR repertoire showed no skewed TCR Vβ usage. Studies on in vitro cytokine production of spleen cells on TCR cross-linking indicated that compared with findings in young mice, the aged mice showed severely impaired production of IL-2, IL-3, and IL-4, whereas the levels of IL-10 and IFN-γ remained relatively intact. FACS-sorted CD69−CD4+ T cells from aged mice produced substantial amounts of these cytokines, including IL-2, IL-3, and IL-4, whereas CD69+CD4+ T cells were poor producers. Intriguingly, when cocultured, CD69+CD4+ T cells significantly inhibited the production of IL-2 by CD69−CD4+ T cells. IL-2 production by spleen cells from young mice was also markedly inhibited in the presence of CD69+CD4+ T cells obtained from aged mice. We propose that CD69+CD4+ T cells that are continuously activated by self peptides bound to MHC class II molecules in (NZB × NZW)F1 mice may be involved in the pathogenesis of SLE through abnormal regulatory effects on cytokine balance.

Summary To determine the phylogenetic positions of two new species, Armillaria jezoensis and Armillaria singula, and one new subspecies, Armillaria mellea suhsp. nipponica, the nucleotide sequences of the intergenic spacers (IGS) of their ribosomal DNA were investigated, and compared with those of tour other Armillaria species from Japan, and those of nine Armillaria species from Europe and North America. We conclude that Armillaria jezoensis, and Armillaria singula belong to the Armillaria gallica cluster as Armillaria cepistipes, Armillaria gallica and Armillaria sinapina from Japan. Two isolates of Armillaria ostoyae from Japan were placed within the Armillaria ostoyae cluster. Armillaria mellea subsp. nipponica had an IGS sequence as long as the IGS of Armillaria mellea from Europe and North America. However, the IGS sequences of Armillaria mellea subsp. nipponica, whose basidium base lacks a clamp connection could not be satisfactorily aligned with the IGS sequences of other species possessing this morphological feature.

This paper describes the development of /spl plusmn/250 kV DC XLPE cables. Through a series of material investigations and the evaluation of model cables using two kinds of XLPE compound containing inorganic filler to suppress the accumulation of space charge within XLPE insulation, /spl plusmn/250 kV DC XLPE cables and factory joints were designed and manufactured. To check the DC electrical performance and reliability of /spl plusmn/250 kV DC submarine cable, electrical tests, mechanical test and long-term aging tests were performed. The test results showed that they had sufficient properties and reliability for practical use.

The space charge in full size 250 kV HVDC power cables was measured using the pulse-electroacoustic method. Measurements of two types of newly developed DC XLPE cables with 20 mm insulation were taken under a DC voltage of 500 kV with the conductor temperature at room temperature and at 85/spl deg/C. A qualitative analysis of the space-charge distribution and a quantitative analysis of the electric fields in the vicinity of semicon interfaces were conducted. It was shown that the field in the vicinity of the inner semicon tends to increase by 10-40% when the polarity of the applied voltage was reversed, in the case when the conductor was kept at 85/spl deg/C. However, the distortion of the electric field was significantly less than that expected in conventional XLPE cables. As the result, the subjected DC cables are considered to have stable DC characteristics from the viewpoint of space charge-behavior.