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The X-ray emission spectrometer at SPring-8 BL07LSU has recently been upgraded with advanced modifications that enable the rotation of the spectrometer with respect to the scattering angle. This major upgrade allows the scattering angle to be flexibly changed within the range of 45-135°, which considerably simplifies the measurement of angle-resolved X-ray emission spectroscopy. To accomplish the rotation system, a sophisticated sample chamber and a highly precise spectrometer rotation mechanism have been developed. The sample chamber has a specially designed combination of three rotary stages that can smoothly move the connection flange along the wide scattering angle without breaking the vacuum. In addition, the spectrometer is rotated by sliding on a flat metal surface, ensuring exceptionally high accuracy in rotation and eliminating the need for any further adjustments during rotation. A control system that integrates the sample chamber and rotation mechanism to automate the measurement of angle-resolved X-ray emission spectroscopy has also been developed. This automation substantially streamlines the process of measuring angle-resolved spectra, making it far easier than ever before. Furthermore, the upgraded X-ray emission spectrometer can now also be utilized in diffraction experiments, providing even greater versatility to our research capabilities. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) exhibit structural flexibility induced by temperature and guest adsorption, as demonstrated in the structural breathing transition in certain MOFs between narrow-pore and large-pore phases. Soft modes were suggested to entropically drive such pore breathing through enhanced vibrational dynamics at high temperatures. In this work, oxygen K-edge resonant X-ray emission spectroscopy of the MIL-53(Al) MOF was performed to selectively probe the electronic perturbation accompanying pore breathing dynamics at the ligand carboxyl­ate site for metal-ligand interaction. It was observed that the temperature-induced vibrational dynamics involves switching occupancy between antisymmetric and symmetric configurations of the carboxylate oxygen lone pair orbitals, through which electron density around carboxylate oxygen sites is redistributed and metal-ligand interactions are tuned. In turn, water adsorption involves an additional perturbation of π orbitals not observed in the structural change solely induced by temperature. [ABSTRACT FROM AUTHOR]

Background: Luteal phase support (LPS) is essential for hormone replacement therapy (HRT) for frozen-thawed embryo transfer (FET). However, the optimal dose and serum progesterone (P4) levels required for pregnancy are controversial. We attempted to determine the association between pregnancy outcomes and serum P4 levels administered via vaginal suppository for HRT-FET cycles on embryo transfer day. Materials and Methods: This was a secondary analysis of the dataset from the EXCULL trial, which prospectively investigated pregnancy outcomes of four different P4 vaginal suppositories (Lutinus, Utrogestan, Luteum, and Crinone) for HRT-FET. It was conducted at a private fertility clinic between December 2016 to December 2017. During this trial, 235 cycles were divided into four groups based on serum P4 values (quartile [Q] 1 group: <7.8 ng/mL; Q2 group: 7.8-10.8 ng/mL; Q3 group: 10.8-13.7 ng/mL; Q4 group: >13.7 ng/mL). We investigated clinical pregnancy rate (CPR), positive fetal heart rate (FHR), live birth rate (LBR), and miscarriage rate (MR) for each group. A logistic regression analysis was performed using age, body mass index (BMI), and transferred embryos as covariates. Results: Serum P4 values (ng/mL) of each drug were as follows: Lutinus, 13.3 ± 4.9; Utrogestan, 9.3 ± 3.3; Luteum, 13.6 ± 4.2; and Crinone, 8.7 ± 3.2 (mean ± standard deviation, P<0.001).The percentages of Utrogestan and Crinone were higher in the Q1 group, while the percentages of Lutinus and Luteum were higher in the Q4 group. Nonetheless, there were no statistical differences between the Q1 and Q4 groups in CPR, FHR, LBR, and MR. Conclusion: When vaginal P4 was used for FET, although serum P4 levels on transfer day differed based on the drug that was administered, no relationship was observed between serum progesteronelevels and pregnancy outcomes (Registration number: UMIN000032997). [ABSTRACT FROM AUTHOR]

The hot deformation behavior of a Mg-14-Li-6A-l1Ca alloy was studied using the hot compression true stressstrain curves corresponding to the temperature range of 473673K at strain rates of 1 × 10-1-1 × 10 3 s 1. The true stressstrain curves indicated dynamic softening under the test conditions. The peak stress during deformation could be correlated with the temperature and strain rate using a hyperbolic-sine equation. The activation energy of the Mg14Li6Al1Ca alloy was determined to be 193 kJ mol-1. The Zener-Hollomon parameter (Z) for the Mg14Li6Al1Ca alloy was determined. The tendency for dynamic recrystallization increases at low strain rates and high temperatures, corresponding to low Z values. The hot deformation behavior of the Mg-14-Li-6A-l1Ca alloy was modelled by a suitable constitutive equation. Furthermore, the size of the equiaxed grains in the hot-deformed and quenched specimens was estimated from the Z value. [ABSTRACT FROM AUTHOR]

We report damage in trenches produced by laser irradiation of a carbon fiber reinforced plastic (CFRP) plate. Laser cutting of CFRP was performed by multi-pass irradiation with a continuouswave fiber IR laser (multi-mode laser, average power: 3.3 kW). The damaged sidewall of the trench in the samples was analyzed by microscopic X-ray computed tomography. Low-speed laser scanning with a galvanometer scanner significantly damaged the sidewall surface and created a wide heat-affected zone. As the thickness of the damaged area was correlated with the scanning speed of the laser beam, the damaged region length was analyzed using the heat penetration depth equation. [ABSTRACT FROM AUTHOR]

We report deep-trench microstructures fabricated on carbon-fiber-reinforced thermoplastic (CFRTP; a CFRP containing thermoplastic resin). Well-defined laser cutting free of debris around the trench was achieved for various types of CFRTP plates by single-mode laser irradiation with a fast beam galvanometer scanner using a multiple-scan-pass method. The microfabrication of a CFRTP containing pitch-type carbon fibers and a polycarbonate resin, performed by 600-scan-pass irradiation with a cw kilowatt single-mode IR fiber laser (average power: 1 kW), yielded a trench microstructure with a depth of 18.2 mm and an opening width of 0.32 mm. The laser-induced damage in the samples was analyzed by microscopic X-ray computed tomography. Laser cutting by high-speed beam scanning resulted in a clean top and excellent sidewall quality, along with a negligible heataffected zone. [ABSTRACT FROM AUTHOR]

We report here laser cutting of carbon fiber reinforced plastic (CFRP) with an IR fiber laser (average power: 2 - 3 kW). The CFRP samples contain thermoplastic resin (CFRTP; carbon fiber reinforced thermo-plastic) or thermosetting resin as binding plastic. Well-defined laser cutting free of debris around the groove was performed for various type of CFRP plates by the laser irradiation with a fast beam galvanometer scanner on a multiple-scan-pass method. The laser-induced damage in the samples was observed and analyzed by microscopic X-ray Computed Tomography. Laser cutting with a high speed beam scanning exhibits a clean top and excellent sidewall quality along with a negligible heat-affected zone. [ABSTRACT FROM AUTHOR]

We report on the laser cutting of carbon fiber reinforced thermo-plastic (CFRTP) with a cw IR fiber laser (average power: 1 kW). CFRTP is a composite material which contains carbon fibers and binding thermoplastic. A well-defined cutting of CFRTP which was free of debris around the groove was performed by the laser irradiation with a fast beam galvanometer scanning on a multiple-scan-pass method. The area of laser-induced damages in the samples was observed by microscopic X-ray Computed Tomography and micro- Raman spectroscopy. Laser cutting with a high speed beam scanning exhibits a clean top and an excellent sidewall quality along with a negligible heat affected zone. [ABSTRACT FROM AUTHOR]

A new soft X-ray beamline, BL07LSU, has been constructed at SPring-8 to perform advanced soft X-ray spectroscopy for materials science. The beamline is designed to achieve high energy resolution (E/ΔE> 10000) and high photon flux [>1012 photons s-1 (0.01% bandwidth)-1] in the photon energy range 250-2000 eV with controllable polarization. To realise this state-of-the-art performance, a novel segmented cross undulator was developed and adopted as a light source. The details of the undulator light source and beamline monochromator design are described. The achieved performance of the beamline, such as the photon flux, energy resolution and the state of polarization, is reported. [ABSTRACT FROM AUTHOR]

Multi-phonon excitations, indicating a strong electron-phonon coupling, were observed by soft X-ray resonant inelastic X-ray scattering of Mg2FeH6 and Mg2FeD6. The Fe-H/D stretch and bend modes are selectively activated by the tuned electron excitation to eg brach of Fe 3d states in octahedral symmetry. The energy deviation with the factor of ∼√2 due to the isotope effect was clearly observed. [ABSTRACT FROM AUTHOR]