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Information on circulating levels of insulin-like peptide 3 (INSL3) in female domesticated animals is limited, as their concentrations are significantly lower than in males. The objectives of the present study were to 1) develop a sandwich time-resolved fluorescence immunoassay (TRFIA) with higher detectability to measure blood INSL3 concentrations in female cattle, 2) determine INSL3 concentrations in female cattle among age groups and reproductive conditions, and 3) explore associations between INSL3 levels and ultrasonographic ovarian measurements. Blood was collected repeatedly from Japanese Black beef female calves (n = 12; 0－8 mo), heifers (n = 10; 10－26 mo), and cows (n = 20; 27－200 mo). Blood was taken from the cows (n = 13) at follicular, post-ovulatory, and luteal phases, and from cows with follicular cysts (n = 12). Ultrasonography of ovaries was conducted in the calves (n = 12) and the cows without ovarian diseases (n = 9). The ovarian area, as well as the number and diameters of antral follicles ≥ 2 mm, were determined in each ovary. The proposed method detected a difference in plasma INSL3 between calves (0.01 ng/mL) and heifers (0.18 ng/mL). However, the conventional assay showed similar levels for calves and heifers (1.82 vs 2.07 ng/mL). Plasma INSL3 and testosterone concentrations increased from calves to heifers (P < 0.0001), but only INSL3 rose from heifers to cows (P < 0.0001). INSL3 and testosterone concentrations did not change across the estrus cycle in cows, and the levels of both hormones in follicular cystic cows did not differ from those in the follicular phase. Ovarian area, maximal and average follicular diameters, and total volume of all follicles per animal were higher in cows than calves (P < 0.001). Plasma INSL3 concentrations correlated positively with the total volumes of all follicles in calves (P < 0.05) and cows (P < 0.05), whereas testosterone concentrations did not correlate with ovarian follicular measurements. In conclusion, plasma INSL3 concentrations measured by the proposed sandwich TRFIA showed a clear increase from female calves to cows in beef cattle. These results suggest that circulating levels of INSL3, but not of testosterone, are associated with the total volume of all antral follicles in both ovaries per animal in female cattle. • Sandwich bovine INSL3 immunoassay was developed with higher sensitivity in plasma. • INSL3 concentrations increased from calves to heifers and from heifers to cows. • INSL3 concentrations correlated with total volume of all follicles in each animal. • Blood INSL3 levels can be a biomarker of ovarian follicular total volume in cattle. [ABSTRACT FROM AUTHOR]

The three-dimensional Fermi-surface structure of hole-doped metallic layered nickelate Eu2-xSrxNiO4 (x = 1.1), an important counterpart to the isostructural superconducting cuprate La2-xSrxCuO4, is investigated by energy-dependent soft-x-ray angle-resolved photoemission spectroscopy. In addition to a large cylindrical hole Fermi surface analogous to the cuprates, we observe a Γ-centered 3z² - r²-derived small electron pocket. This finding demonstrates that in the layered nickelate the 3z² - r² band resides close to the x² - y² one in energy. The resultant multiband feature with varying orbital character as revealed may strongly work against the emergence of the high-temperature superconductivity. [ABSTRACT FROM AUTHOR]

There has been increasing interest in phenomena emerging from relativistic electrons in a solid, which have a potential impact on spintronics and magnetoelectrics. One example is the Rashba effect, which lifts the electron-spin degeneracy as a consequence of spin-orbit interaction under broken inversion symmetry. A high-energy-scale Rashba spin splitting is highly desirable for enhancing the coupling between electron spins and electricity relevant for spintronic functions. Here we describe the finding of a huge spin-orbit interaction effect in a polar semiconductor composed of heavy elements, BiTeI, where the bulk carriers are ruled by large Rashba-like spin splitting. The band splitting and its spin polarization obtained by spin- and angle-resolved photoemission spectroscopy are well in accord with relativistic first-principles calculations, confirming that the spin splitting is indeed derived from bulk atomic configurations. Together with the feasibility of carrier-doping control, the giant-Rashba semiconductor BiTeI possesses excellent potential for application to various spin-dependent electronic functions. [ABSTRACT FROM AUTHOR]

Time-resolved photoelectron spectroscopy (trPES) can directly detect transient electronic structure, thus bringing out its promising potential to clarify nonequilibrium processes arising in condensed matters. Here we report the result of core-level trPES on 1T-TaS2, realized by developing a high-intensity 60-eV laser obtained by high-order harmonic generation. Ta4f core-level trPES offers the transient amplitude of the charge-density wave (CDW), via the site-selective and real-time observation of Ta electrons. The present result indicates an ultrafast photoinduced melting and recovery of CDW amplitude, followed by a peculiar long-life oscillation (i.e., collective amplitudon excitation) accompanying the transfer of electrons among adjacent Ta atoms. core-level trPES offers a broad range of opportunities for investigating the ultrafast atom-specific electron dynamics in photorelated phenomena of interest. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the low-energy electronic state of boron-doped diamond thin film by the laser-excited photoemission spectroscopy. A clear Fermi-edge is observed for samples doped above the semiconductor–metal boundary, together with the characteristic structures at possibly due to the strong electron–lattice coupling effect. In addition, for the superconducting sample, we observed a shift of the leading edge below indicative of a superconducting gap opening. We discuss the electron–lattice coupling and the superconductivity in doped diamond. [Copyright &y& Elsevier]

A novel switch-mode voltage-doubler rectifier for single-phase supply is presented. It consists of diode bridge circuit and pump circuit with symmetrical arrangement of capacitors. The capacitors with energy storage/transfer capability are charged and discharged by employing the active power semiconductor devices. The rectifier can be operated in the switch mode for pumping action to pump twice the peak supply voltage into the output capacitor and for forcing the input current to follow its sinusoidal reference independent of the working conditions. The prototype tested, using two dual-IGBT power modules, has been implemented to investigate the operation with a PT controller for output voltage regulation. Experimental and simulated results are provided to verify the expected performance in both steady-state and transient conditions. [ABSTRACT FROM AUTHOR]

By combining the scanning transmission electron microscopy with the ultrafast optical pump–probe technique, we improved the time resolution by a factor of ∼1012 for the differential phase contrast and convergent-beam electron diffraction imaging. These methods provide ultrafast nanoscale movies of physical quantities in nano-materials, such as crystal lattice deformation, magnetization vector, and electric field. We demonstrate the observations of the photo-induced acoustic phonon propagation with an accuracy of 4 ps and 8 nm and the ultrafast demagnetization under zero magnetic field with 10 ns and 400 nm resolution, by utilizing these methods. [ABSTRACT FROM AUTHOR]

Serum IgE levels in twelve patients with adult 'acquired' hypogammaglobulinaemia were markedly reduced. In addition, seventeen of fifty first degree relatives and spouses had low IgE levels. IgE levels varied among patients with selective IgA deficiency and a combined deficiency did not necessarily predispose to recurrent infections. This study suggests that the absence of IgE in certain immune deficiency states does not, by itself, decrease resistance to infection. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the bulk superconducting electronic structure in optimally doped (YBCO) using laser-excited angle-resolved photoemission spectroscopy. The band dispersions with the -wave like gap opening are observed without being hindered by surface state and CuO chain band due to bulk-sensitivity and/or matrix element effect at . The momentum-dependence of the superconducting gap exhibits a nonzero minimum of ∼12meV along the line. In addition, the unusual suppression of the quasiparticle coherence is observed at . [ABSTRACT FROM AUTHOR]

We have investigated the low-energy electronic state of boron-doped diamond thin film by the laser-excited photoemission spectroscopy. A clear Fermi-edge is observed for samples doped above the semiconductor–metal boundary, together with the characteristic structures at 150×n meV possibly due to the strong electron–lattice coupling effect. In addition, for the superconducting sample, we observed a shift of the leading edge below Tc indicative of a superconducting gap opening. We discuss the electron–lattice coupling and the superconductivity in doped diamond. [ABSTRACT FROM AUTHOR]

This paper reports the characteristics of planar contactless power transfer systems, which are classified into the following types: single-phase primary and single-phase secondary system (SS system), three-phase primary and single-phase secondary system (TS system), and three-phase primary and three-phase secondary system (TT system). The SS system is used in conventional contactless power transfer. On the other hand, in the last few years, the TS system has been studied more. As a novel system, the TT system is here proposed. The characteristics of all three systems are measured by using a common experimental prototype made of printed circuit board. The comparison confirms that the TT system has higher efficiency and can output uniform power independent of the secondary position, as compared to the other systems. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the dispersion in the hole Fermi surfaces (FSs) and the superconducting (SC) gaps of BaFe2(As0.65P0.35)2 by employing bulk-sensitive angle-resolved photoemission spectroscopy (ARPES) with low energy photons. We find that this material exhibits a comparable magnitude of SC gaps for three-hole FSs at . The comparable magnitude of the SC gap is observed also at 0. Since each FS sheet has a distinct orbital character, these observations are an indication of the orbital-independent SC gaps in the hole FSs. [Copyright &y& Elsevier]

The origin of superconductivity in the iron pnictides has been attributed to antiferromagnetic spin ordering that occurs in close combination with a structural transition, but there are also proposals that link superconductivity to orbital ordering. We used bulk-sensitive laser angle-resolved photoemission spectroscopy on BaFe2(As0.65P0.35)2 and Ba0.6K0.4Fe2As2 to elucidate the role of orbital degrees of freedom on the electron-pairing mechanism. In strong contrast to previous studies, an orbital-independent superconducting gap magnitude was found for the hole Fermi surfaces. Our result is not expected from the superconductivity associated with spin fluctuations and nesting, but it could be better explained invoking magnetism-induced interorbital pairing, orbital fluctuations, or a combination of orbital and spin fluctuations. Regardless of the interpretation, our results impose severe constraints on theories of iron pnictides. [ABSTRACT FROM AUTHOR]

We have developed a low temperature ultrahigh resolution system for polarization dependent angle-resolved photoemission spectroscopy (ARPES) using a vacuum ultraviolet (vuv) laser (hν=6.994 eV) as a photon source. With the aim of addressing low energy physics, we show the system performance with angle-integrated PES at the highest energy resolution of 360 μeV and the lowest temperature of 2.9 K. We describe the importance of a multiple-thermal-shield design for achieving the low temperature, which allows a clear measurement of the superconducting gap of tantalum metal with a Tc=4.5 K. The unique specifications and quality of the laser source (narrow linewidth of 260 μeV, high photon flux), combined with a half-wave plate, facilitates ultrahigh energy and momentum resolution polarization dependent ARPES. We demonstrate the use of s- and p-polarized laser-ARPESs in studying the superconducting gap on bilayer-split bands of a high Tc cuprate. The unique features of the quasi-continuous-wave vuv laser and low temperature enables ultrahigh-energy and -momentum resolution studies of the spectral function of a solid with large escape depth. We hope the present work helps in defining polarization dependent laser excited angle-resolved photoemission spectroscopy as a frontier tool for the study of electronic structure and properties of materials at the sub-meV energy scale. [ABSTRACT FROM AUTHOR]

Lithium-doped K0.5Na0.5NbO3 (KLNN) films were fabricated by chemical solution deposition on Pt/TiO2/SiO2/Si substrates. Homogeneous and stable precursor solutions were prepared by controlling the reaction of starting metal alkoxides. Perovskite KLNN single-phase thin films were successfully synthesized on Pt/TiOx/SiO2/Si substrates. The 0.75-μ m-thick KLNN film annealed at 650°C exhibited ferroelectric polarization hysteresis loops at -250°C. The loop at room temperature was round, indicating the film contained leakage components. The dielectric constant under zero bias was 490 at room temperature. A typical upside-down butterfly DC bias-capacitance curve was obtained in the KLNN film capacitors at room temperature, indicating that polarization reversal occurred in the obtained KLNN films. [ABSTRACT FROM AUTHOR]

This study was designed to examine the effects of dietary vitamin E on antioxidant status and nonspecific immune responses of rainbow trout (Oncorhynchus mykiss) fed different lipids. Six semi-purified diets containing three lipid sources: pollock liver oil (PO), linseed oil (LO) and safflower oil (SO), each in combination with two levels of vitamin E (100 and 1000 mg α-tocopheryl acetate kg−1 diet), were fed to duplicate groups of 17 g fish for 9 weeks. The growth performances were significantly greater in the PO and LO groups compared to the SO fed fish, irrespective of vitamin E content. The hematocrit (Hct) values were also higher in the PO and LO fed fish suggesting that n−3 fatty acids in these oils were more involved in erythropoiesis. The red blood cells (RBCs) were less fragile in fish fed PO diets, regardless of vitamin E levels. The hydroperoxide content in red blood cells and superoxide dismutase (SOD) in plasma were slightly higher in fish fed 1000 mg vitamin E kg−1 diet suggesting that the antioxidant capacity of the vitamin at the high level was not evident compared to that at the lower level. On the other hand, only minor modulations of the immune responses related to vitamin E were observed for the three lipid groups. The total immunoglobulin (Ig) and phagocyte activity were lower while serum alternative complement and lysozyme activities, and the production of reactive oxygen species by head kidney leucocytes were higher in fish fed the higher amount of vitamin E. Although most of results in this study were not statistically significant, the prooxidant tendency of vitamin E observed at the high dose has to be examined carefully in relation to health of fish. [Copyright &y& Elsevier]

A switch-mode voltage-doubler rectifier using a capacitive energy storage/transfer mechanism is studied in the paper. The voltage doubling can be provided by means of a high frequency pumping action of the capacitor. Moreover, the rectifier is operated in the switching state for forcing the input current to follow its sinusoidal reference independently of the working conditions by discharging the capacitor to the circuit consisting of the supply and the boost inductor. The arrangement tested, using three insulated-gate bipolar transistors and a microcomputer as a PI controller, is used to investigate experimentally the steady-state and transient characteristics. The experimental and simulated results confirm that the rectifier can be operated with a good quality input current under steady-state and transient conditions. [ABSTRACT FROM AUTHOR]

Summary. The numbers of Sertoli and pre-meiotic germ cells in the developing rabbit testis were investigated as an initial step in determining the physiological meaning of the control of cell number in the testis by apoptosis. Sections were stained immunohistochemically for the detection of apoptotic cells and counterstained with haematoxylin. The number resulting from subtraction of the number of apoptotic cells from the total cell number was defined as the viable cell number. The number of viable pre-meiotic germ cells in the adluminal compartment of seminiferous tubules decreased during the pre-natal period, although neither apoptotic nor necrotic figures were detected. After birth, the numbers of total and apoptotic Sertoli and pre-meiotic germ cells increased, maintaining a stable ratio of their viable cell populations until the induction of meiosis. During induction of meiosis, the increase in the number of viable Sertoli cells was significantly accelerated because of the rapid decrease in the number of apoptotic Sertoli cells. Just after spermatids were formed the number of viable spermatogonia increased, reflecting an active supply of differentiated spermatogonia entering meiosis. In conclusion, apoptosis of Sertoli and pre-meiotic germ cells plays an important role in the acquisition of a suitable ratio of both cell types, and in providing intratubular environments for further progression of spermatogenesis, by controlling numbers of both cell types during the post-natal period. [ABSTRACT FROM AUTHOR]

A melilite-olivine nephelinite lava flow occurring in Hamada, SW Japan, is the most silica-undersaturated lava known to have erupted in Japan (SiO2 content ~37 wt %), and may be a least fractionated melt from mantle depths. Heterogeneity of elements such as Si, Al, Ca, and alkaline elements is one of the characteristic features of the Hamada nephelinites and is attributed to hydrothermal alteration, because these elements' concentrations correlate with H2O contents. Melting phase relations at high pressures on the least altered nephelinite sample in the presence both of H2O and CO2 demonstrated that the nephelinite melt is multiply saturated with olivine and clinopyroxene but not with orthopyroxene, suggesting that the nephelinite magma was not derived from a lherzolite source, but possibly from a wehrlite source. Such an unusual mantle material may have been formed by carbonate metasomatism of a lherzolitic upper mantle, which is a process consistent with the geochemical characteristics of the Hamada nephelinite lava. [ABSTRACT FROM PUBLISHER]

Serum IgE levels can be measured by reverse passive antiglobulin haemagglutination (RPAH) using trypsin-treated human red cells coupled to anti-human IgE by chromic chloride. The results are read after only 90 min incubation. RPAH and double antibody radioimmunoassay have been used to measure IgE levels in 100 sera, with levels ranging from 5 to 43,000 international units (i.u.)/ml. Correlation between the two assays was high over the whole range, provided that affinity-purified anti-IgE was used in the RPAH test. When two non-atfinity-purified anti-IgE reagents were used in the RPAH, correlation was poor for sera with levels below 1000i.u./mi. It is concluded that RPAH tests for IgE are of comparable sensitivity and specificity to radioimmunoassay procedures, and provide a useful simple, yet more rapid alternative. [ABSTRACT FROM AUTHOR]

Leucocytes from allergic and most normal human donors release histamine when challenged with antibodies against human γ-globulin. This reaction (reversed in vitro anaphylaxis) is due primarily to anti-IgE antibodies although there is some response in most donors to antisera against IgG even after it has been absorbed with light and ε chains. The anti-IgE is, however, several 100-fold more potent than the anti-IgG. By passive sensitization of the leucocytes of a normal donor with serum from a ragweed-allergic patient it was shown that the normal cells became sensitive to anti-IgE and ragweed antigen E at the same time; in both cases, there was an inverse relationship between the serum concentration used for passive sensitization and the concentration of antigen or antibody required for histamine release. There is a rough correlation (rs = 0.42; P<0.01) between the serum IgE concentration and the response of leucocytes from allergic donors to anti-IgE and an excellent correlation (rs = 0.82; P<0.01) between the response of the cells to ragweed antigen E and anti-IgE. There is also a strong parallel between the mechanism of direct, antigen mediated histamine release and the reversed reaction induced by anti-IgE. Both appear to be nonserum requiring, non-cytotoxic, secretory-like responses which are inhibited by theophylline, cyclic AMP and colchicine. These data suggest that cell bound IgE is of major importance in the in vitro anaphylactic response and that the direct and reversed in vitro anaphylactic reactions both operate through cell-bound IgE and share a common reaction mechanism. [ABSTRACT FROM AUTHOR]

We have investigated the temperature variation of optical spectra for single crystals of Nd2-xCexCuO4 (0.05⩽x⩽0.15). While little temperature variation has been observed in the optical spectrum of the x=0.15 crystal, we have found a notable pseudogap as large as 0.2–0.4 eV at low temperature for the underdoped crystals (x<0.15). Drude-like response also evolves concomitantly with the pseudogap formation. The onset temperature (T*) of the pseudogap decreases with electron doping. The origin of the pseudogap has been ascribed to the antiferromagnetic correlation. [Copyright &y& Elsevier]

Ultrahigh-repetition-rate (1.1 GHz), deep-ultraviolet coherent light at 208.8 nm is generated by applying an external Fabry–Pérot cavity for repetition-rate multiplication to the fourth harmonics of a 10-ps, mode-locked Ti:sapphire laser. Its small pulse energy minimizes the unwanted space charge effect, while its high repetition rate drastically reduces the acquisition time in high-energy resolution angle-resolved photoemission spectroscopy using hemispherical electron analyzers. The absence of the space charge effect in the photoemission spectrum near the Fermi edge of polycrystalline Au at 8 K demonstrates this idea. [ABSTRACT FROM AUTHOR]

On railway lines in mountainous areas, wheel slip and wheel slide frequently occurr due to a decrease in adhesion coefficient caused by fallen leaves in wet conditions. One of the countermeasure is tree felling, and knowing which tree species significantly reduce the adhesion coefficient is helpful in determining the order of priority for felling. In this study, the tangential force coefficient, which is strongly correlated with the adhesion coefficient and the maximum tangential force coefficient is generally defined as the adhesion coefficient, was quantitatively assessed for fallen leaves of five tree species using a rolling-slip friction measurement machine. The experimental results showed that the tangential force coefficients in order of lowest to highest belong to ginkgo, cedar, cherry, maple, and zelkova in wet conditons. This experiment identified which tree species are more slippery and have a high priority for felling. • Adhesion coefficient decreases when leaves are interposed between wheel and rail. • Adhesion coefficient is about 0.225 and 0.053 in dry and wet conditions, respectively. • Adhesion coefficient is about 65% lower than no leaves in dry conditions. • Adhesion coefficient is about 75% lower than no leaves in wet conditions. [ABSTRACT FROM AUTHOR]

The relationship between the superconducting gap and the pseudogap has been the subject of controversies. In order to clarify this issue, we have studied the superconducting gap and pseudogap of the high-Tc superconductor La2-xSrxCuO4 (x = 0.10,14) by angle-resolved photoemission spectroscopy (ARPES). Through the analysis of the ARPES spectra above and below Tc, we have identified a superconducting coherence peak even in the antinodal region on top of the pseudogap of a larger energy scale. The superconducting peak energy nearly follows the pure d-wave form. The d-wave order parameter Δ0 [defined by Δ(k) = Δ0(cos kxa - cos kya) ] for x = 0.10 and 0.14 are nearly the same, Δ0 ∼ 12-14 meV, leading to strong coupling 2Δ0/kBTc ∼ 10. The present result indicates that the pseudogap and the superconducting gap are distinct phenomena and can be described by the "two-gap" scenario. [ABSTRACT FROM AUTHOR]

We investigate the electronic reconstruction across the tetragonal-orthorhombic structural transition in FeSe by employing polarization-dependent angle-resolved photoemission spectroscopy on detwinned single crystals. Across the structural transition, the electronic structures around the Г and M points are modified from fourfold to twofold symmetry due to the lifting of degeneracy in dxz/dyz orbitals. The dxz band shifts upward at the T point, while it moves downward at the M point, suggesting that the electronic structure of orthorhombic FeSe is characterized by a momentum-dependent sign-changing orbital polarization. Due to this sign-changing orbital order, the elongated directions of the elliptical Fermi surfaces at the Г and M points are rotated by 90° with respect to each other, which makes the nesting condition between these FSs imperfect. The present result, supported by calculations, indicates the possible suppression of the spin-fluctuation mediated superconductivity in the orthorhombic FeSe, as compared to the orbital-ordered state without sign change. [ABSTRACT FROM AUTHOR]

We have performed time-resolved (TR) core-level and valence-band angle-resolved (AR) photoemission spectroscopy (PES) to investigate ultrafast dynamics of an electron-doped topological insulator Cu0.17Bi2Se3. The Bi 5d5/2 line was composed of a single peak and exhibited broadening upon both heating and pumping, which we interpreted as a change of phonon temperature (Tp), in the surface region. The electronic dynamics and electron temperature (Te), on the other hand, were determined with near-EF TRARPES. The transient temperature deduced from core-level TRPES shows a similar behavior with Te deduced from near-EF TRARPES. This similar behavior of Tp and Te can be reproduced not by a simple two-temperature model but by a modified one, although we cannot exclude a possibility that core-level broadening also reflects Te. [ABSTRACT FROM AUTHOR]

We report peculiar momentum-dependent anisotropy in the superconducting gap observed by angle-resolved photoemission spectroscopy in BaFe2(As1-xPx)2 (x = 0.30, Tc = 30 K). Strongly anisotropic gap has been found only in the electron Fermi surface while the gap on the entire hole Fermi surfaces are nearly isotropic. These results are inconsistent with horizontal nodes but are consistent with modified s± gap with nodal loops. We have shown that the complicated gap modulation can be theoretically reproduced by considering both spin and orbital fluctuations. [ABSTRACT FROM AUTHOR]

We study superconducting FeSe (Tc = 9 K) exhibiting the tetragonal-orthorhombic structural transition (Ts ~ 90 K) without any antiferromagnetic ordering, by utilizing angle-resolved photoemission spectroscopy. In the detwinned orthorhombic state, the energy position of the dyz orbital band at the Brillouin zone comer is 50meV higher than that of dxz, indicating the orbital order similar to the NaFeAs and BaFe2As2 families. Evidence of orbital order also appears in the hole bands at the Brillouin zone center. Precisely measured temperature dependence using strain-free samples shows that the onset of the orbital ordering (To) occurs very close to Ts, thus suggesting that the electronic nematicity above Ts is considerably weaker in FeSe compared to BaFe2As2 family [ABSTRACT FROM AUTHOR]

The valley degree of freedom of electrons is attracting growing interest as a carrier of information in various materials, including graphene, diamond and monolayer transition-metal dichalcogenides. The monolayer transition-metal dichalcogenides are semiconducting and are unique due to the coupling between the spin and valley degrees of freedom originating from the relativistic spin-orbit interaction. Here, we report the direct observation of valley-dependent out-of-plane spin polarization in an archetypal transition-metal dichalcogenide-MoS2-using spin- and angle-resolved photoemission spectroscopy. The result is in fair agreement with a first-principles theoretical prediction. This was made possible by choosing a 3R polytype crystal, which has a non-centrosymmetric structure, rather than the conventional centrosymmetric 2H form. We also confirm robust valley polarization in the 3R form by means of circularly polarized photoluminescence spectroscopy. Non-centrosymmetric transition-metal dichalcogenide crystals may provide a firm basis for the development of magnetic and electric manipulation of spin/valley degrees of freedom. [ABSTRACT FROM AUTHOR]

Pituitary adenylate cyclase-activating peptide ( PACAP) is a neuropeptide expressed in the central nervous system and peripheral organs. Previous studies revealed the role and distribution of PACAP in the rodent testis, however, its presence in the human testis and in testicular germ cell tumors is not known. We used RT- PCR and immunohistological observations to investigate whether human testicular tissue and testicular germ cell tumors contain PACAP. The mRNAs for PACAP and its receptors were detected in total RNA extracted from human testes. PACAP immunoreactivity was observed in spermatogonia and spermatids from normal testes. In contrast, diffuse PACAP immunopositivity was observed in seminoma tumor cells, while only faint immunoreactivity was observed in embryonal carcinoma cells. Our data suggest that PACAP may play a role in human spermatogenesis and in testicular germ cell tumor development. [ABSTRACT FROM AUTHOR]

In Fe-based superconductors, electron doping is often realized by the substitution of transition-metal atoms for Fe. In order to investigate how the electronic structure of the parent compound is influenced by Zn substitution, which supplies nominally four extra electrons per substituted atom but is expected to induce the strongest impurity potential among the transition-metal atoms, we have performed an angle-resolved photoemission spectroscopy measurement on Ba(Fe1-xZnx)2As2 (Zn-122). In Zn-122, the temperature dependence of the resistivity shows a kink around T ~ 135 K, indicating antiferromagnetic order below the Néel temperature of TN ~ 135 K. In fact, folded Fermi surfaces (FSs) similar to those of the parent compound have been observed below TN. The hole and electron FS volumes are, therefore, different from those expected from the rigid-band model. The results can be understood if all the extra electrons occupy the Zn 3d state ~10 eV below the Fermi level and do not participate in the formation of the FSs. [ABSTRACT FROM AUTHOR]

We investigate the two-dimensional highly spin-polarized electron accumulation layers commonly appearing near the surface of «-type polar semiconductors BiTeX (X = I, Br, and CI) by angular-resolved photoemission spectroscopy. Because of the polarity and the strong spin-orbit interaction built in the bulk atomic configurations, the quantized conduction-band subbands show giant Rashba-type spin splitting. The characteristic 2D confinement effect is clearly observed also in the valence bands down to the binding energy of 4 eV. The X-dependent Rashba spin-orbit coupling is directly estimated from the observed spin-split subbands, which roughly scales with the inverse of the band-gap size in BiTeX. [ABSTRACT FROM AUTHOR]

Charge dynamics and its critical behavior are investigated near the metal-insulator transition of layered-nickelate R2-xSrxNiO4(x~1) (R = Nd, Eu). The polarized x-ray absorption spectroscopy experiment clearly shows the multiorbital nature which enables the x² -- y²-orbital-based checkerboard-type charge ordering or correlation to persist up to the critical doping region (x ~ 1). In the barely metallic region proximate to the charge-ordered insulating phase, the nominal carrier density estimated from the Hall coefficient markedly decreases in accord with development of the pseudogap structure in the optical conductivity spectrum, while the effective mass is least enhanced. The present findings combined with the results of recent angle-resolved photoemission spectroscopy show that the pseudogap in the metal-insulator critical state evolves due to the checkerboard-type charge correlation to extinguish the coherent-motion carriers in a characteristic momentum (k)-dependent manner with lowering temperature. [ABSTRACT FROM AUTHOR]

We report on the electronic structure of the perovskite oxide CaCrO3 using valence-band, core-level, and Cr 2p-3d resonant photoemission spectroscopy (PES). Despite its antiferromagnetic order, a clear Fermi edge characteristic of a metal with dominant Cr 3d character is observed in the valence-band spectrum. The Cr 3d single-particle density of states are spread over 2 eV, with the photoemission spectral weight distributed in two peaks centered at ~1.2 and 0.2 eV below EF, suggestive of the coherent and incoherent states resulting from strong electron-electron correlations. Resonant PES across the Cr 2p-3d threshold identifies a "two-hole" correlation satellite and yields an on-site Coulomb energy U~ 4.8 eV. The metallic DOS at EF is also reflected through the presence of a well-screened feature at the low binding energy side of the Cr 2p core-level spectrum. X-ray-absorption spectroscopy at Cr L3,2 and O K edges exhibit small temperature-dependent changes that point toward a small change in Cr-O hybridization. The Cr 2p core-level spectrum can be reproduced using cluster model calculations that include a charge transfer from the metallic screening channel at EF. The overall results indicate that CaCrO3 is a strongly hybridized antiferromagnetic metal, lying in the regime intermediate to Mott-Hubbard and charge-transfer systems. [ABSTRACT FROM AUTHOR]

We have studied the momentum dependence of the energy gap of Bi2(Sr,R)2CuOy by angle-resolved photoemission spectroscopy (ARPES), particularly focusing on the difference between R=La and Eu. By comparing the gap function and characteristic temperatures between the two sets of samples, we show that there exist three distinct energy scales, Δpg, Δsc0, and Δsc0eff, which correspond to T* (pseudogap temperature), Tonset (onset temperature of fluctuating superconductivity), and Tc (critical temperature of coherent superconductivity). The results not only support the existence of a pseudogap state below T* that competes with superconductivity, but also the duality of competition and superconducting fluctuation at momenta around the antinode below Tonset. [ABSTRACT FROM AUTHOR]

Abstract: Tsubame is a university-built small satellite mission to measure polarization of hard X-ray photons (30–200keV) from gamma-ray bursts (GRB) using azimuthal angle anisotropy of Compton-scattered photons. Polarimetry in the hard X-ray and soft gamma-ray band should play a crucial role in understanding of high energy emission mechanisms, the distribution of magnetic fields and radiation fields of gamma-ray bursts. Tsubame has two instruments: the Wide-field Bust Monitor (WBM) and the Hard X-ray Compton Polarimeter (HXCP). The WBM detects a burst and determines on board the direction of the burst occurrence with an accuracy of 10°. The spacecraft is then slewed to point the GRB within 15s from the WBM trigger using the Control Moment Gyro (CMG), a high speed attitude control device. HXCP will measure the polarized X-ray photons from the GRB while the spacecraft spins slowly around the bore sight. In this paper, we present an overview of the Tsubame mission, the results of a test experiment for HXCP using a polarized hard X-ray beam, and its comparison with a Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

Abstract: We have performed temperature (T)-dependent laser-photoemission spectroscopy of antiferromagnetic (AF) superconductor ErNi2B2C to study the electronic structure, especially the effect of AF ordering in T-dependent superconducting (SC) gap. To estimate the values of T-dependent SC gap, we fitted the experimental data by Dynes function having an anisotropic s-wave SC gap. From the fitting results, we find a sudden deviation from the BCS prediction just below T N. This observation can be well explained by the theoretical model, indicating that the origin of anomalous T-dependence is competition between rapid evolution of AF molecular field and SC condensation energy. [Copyright &y& Elsevier]

Abstract: Cathode spot behavior during vacuum arc cleaning (VAC) of a metal surface covered with an oxide layer is investigated using a pulse discharge. During VAC, a bright spot is visible. A dot-like trace is marked on the cathode surface by the removed oxide layer. Detailed surface analyses show that the surface roughness is increased and that the oxide layer is stripped off almost uniformly in the trace. The cathode spot size adjustment is more precise than in our previous experiment. Spot characteristics change concomitantly with variation of the discharge electric power. [Copyright &y& Elsevier]

The magnetoelectric effect-the induction of magnetization by means of an electric field and induction of polarization by means of a magnetic field-was first presumed to exist by Pierre Curie, and subsequently attracted a great deal of interest in the 1960s and 1970s (refs 2-4). More recently, related studies on magnetic ferroelectrics have signalled a revival of interest in this phenomenon. From a technological point of view, the mutual control of electric and magnetic properties is an attractive possibility, but the number of candidate materials is limited and the effects are typically too small to be useful in applications. Here we report the discovery of ferroelectricity in a perovskite manganite, TbMnO3, where the effect of spin frustration causes sinusoidal antiferromagnetic ordering. The modulated magnetic structure is accompanied by a magnetoelastically induced lattice modulation, and with the emergence of a spontaneous polarization. In the magnetic ferroelectric TbMnO3, we found gigantic magnetoelectric and magnetocapacitance effects, which can be attributed to switching of the electric polarization induced by magnetic fields. Frustrated spin systems therefore provide a new area to search for magnetoelectric media. [ABSTRACT FROM AUTHOR]

Abstract: We present the data from ultrahigh-resolution laser-excited photoemission spectroscopy on a newly discovered noncentrosymmetric superconductor Mg10Ir19B16. We observed the evidences for the opening of superconducting gap where numerical fittings show that isotropic s-wave model can satisfactorily explain the behavior of spectra near the Fermi level. We also present the valence band photoemission spectrum and B K fluorescence spectrum to discuss the basic electronic structure of Mg10Ir19B16. [Copyright &y& Elsevier]

The chiral crystal is characterized by a lack of mirror symmetry and inversion center, resulting in the inequivalent right- and left-handed structures. In the noncentrosymmetric crystal structure, the spin and momentum of electrons are expected to be locked in the reciprocal space with the help of the spin-orbit interaction. To reveal the spin textures of chiral crystals, we investigate the spin and electronic structure in a p-type semiconductor, elemental tellurium, with the simplest chiral structure by using spin- and angle-resolved photoemission spectroscopy. Our data demonstrate that the highest valence band crossing the Fermi level has a spin component parallel to the electron momentum around the Brillouin zone corners. Significantly, we have also confirmed that the spin polarization is reversed in the crystal with the opposite chirality. The results indicate that the spin textures of the right- and left-handed chiral crystals are hedgehoglike, leading to unconventional magnetoelectric effects and nonreciprocal phenomena. [ABSTRACT FROM AUTHOR]

GeTe is a chemically simple IV-VI semiconductor which bears a rich plethora of different physical properties induced by doping and external stimuli. Here, we report a superconductor-semiconductor-superconductor transition controlled by finely-tuned In doping. Our results reveal the existence of a critical doping concentration xc=0.12 in Ge1-xInxTe, where various properties, including structure, resistivity, charge carrier type, and the density of states, take either an extremum or change their character. At the same time, we find indications of a change in the In-valence state from In3+ to In1+ with increasing x by core-level photoemission spectroscopy, suggesting that this system is a new promising playground to probe valence fluctuations and their possible impact on structural, electronic, and thermodynamic properties of their host. [ABSTRACT FROM AUTHOR]

We investigate the surface electronic structures of polar 1T'-MoTe2, the Weyl semimetal candidate realized through the nonpolar-polar structural phase transition, by utilizing the laser angle-resolved photoemission spectroscopy combined with first-principles calculations. Two kinds of domains with different surface band dispersions are observed from a single-crystalline sample. The spin-resolved measurements further reveal that the spin polarizations of the surface and the bulk-derived states show the different domain dependences, indicating the opposite bulk polarity. For both domains, some segmentlike band features resembling the Fermi arcs are clearly observed. The patterns of the arcs present the marked contrast between the two domains, respectively agreeing well with the slab calculation of (0 0 1) and (0 0 -1) surfaces. The present result strongly suggests that the Fermi arc connects the identical pair of Weyl nodes on one side of the polar crystal surface, whereas it connects between the different pairs of Weyl nodes on the other side. [ABSTRACT FROM AUTHOR]