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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.

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.

Carbon Fiber Reinforced Plastic (CFRP) is a composite material consisting of a resin matrix and carbon fiber reinforcement. The material is also commonly used in a prepreg laminate, a unidirectional reinforcing material with high strength and stiffness in one direction. Damage to laminates is highly complex, including delamination, fiber fracture, and base matrix cracking, requiring highly efficient and accurate non-destructive testing. Infrared stress measurement is an example of a non-destructive testing method for CFRP structures. The infrared stress measurement is based on Kelvin’s theory to convert the surface temperature fluctuation under cyclic loading to the distributions of sum of principal stress on surface (DSPSS), so it may result in a stress distribution that differs from the actual distribution due to transient heat conduction. It is necessary to consider structural analysis and transient heat conduction in the numerical analysis to reproduce DSPSS obtained by infrared stress measurement. This study performs a finite element analysis with transient heat conduction on simple shaped CFRP specimens to reproduce the trend of DSPSS obtained by infrared stress measurement. Firstly, DSPSS generated by the forced displacement of a CFRP specimen is converted to a temperature distribution using Kelvin’s thermoelastic theory. Finally, a transient heat conduction analysis is performed, and the distribution trend is discussed using the obtained temperature distribution as the initial value. A sheet of Teflon is inserted into the CFRP specimen as a defect, assuming foreign matter contamination during the manufacturing process. Previous study predicts the internal defect information by a machine learning model using the DSPSS from numerical analysis. There is a potential for a high-accuracy defect prediction using DSPSS obtained by the infrared stress measurement if DSPSS obtained by the infrared stress measurement and the numerical analysis have similar tendencies.

Abstract Lithium-ion deintercalation/intercalation during charge/discharge processes is one of the essential reactions that occur in the layered cathodes of lithium-ion batteries, and the performance of the cathode can be expressed as the sum of the reactions that occur in the local area of the individual cathode particles. In this study, the spatial distributions of the chemical states present in prototypical layered LiCoO2 cathode particles were determined at different charging conditions using scanning transmission X-ray microscopy (STXM) with a spatial resolution of approximately 100 nm. The Co L 3- and O K-edge X-ray absorption spectroscopy (XAS) spectra, extracted from the same area of the corresponding STXM images, at the initial state as well as after charging to 4.5 V demonstrate the spatial distribution of the chemical state changes depending on individual particles. In addition to the Co L 3-edge XAS spectra, the O K-edge XAS spectra of the initial and charged LiCoO2 particles are different, indicating that both the Co and O sites participate in charge compensation during the charging process possibly through the hybridization between the Co 3d and O 2p orbitals. Furthermore, the element maps of both the Co and O sites, derived from the STXM stack images, reveal the spatial distribution of the chemical states inside individual particles after charging to 4.5 V. The element mapping analysis suggests that inhomogeneous reactions occur on the active particles and confirm the existence of non-active particles. The results of this study demonstrate that an STXM-based spatially resolved electronic structural analysis method is useful for understanding the charging and discharging of battery materials.

We study high harmonic generation (HHG) in the visible spectral range generated in a flat liquid jet of H _2 O, excited by intense mid-infrared (MIR) radiation around 3 μm, which is nearly resonant with the OH vibrational modes. By introducing a weak excitation pulse prior to the intense MIR driver pulse for HHG, we observed an enhancement of the 5th, 7th, and 9th harmonics occurring approximately 2 ps after excitation and persisting for more than 120 ps, which is completely absent in the case of non-resonant D _2 O. These results suggest that the enhancement is caused by ultrafast heating through vibrational excitation.

Abstract An X-ray is the well-known probe to examine structure of materials, including our own bodies. The X-ray beam, especially at the wavelength of nanometers, has also become significant to directly investigate electronic states of a sample. Such an X-ray is called a soft X-ray and polarization dependence of the light-matter interaction further unveils the microscopic properties, such as orbitals or spins of electrons. Generation of high brilliant beams of the polarized X-ray has linked to development of our experimental science, and it has been made by radiation from relativistic electrons at the synchrotron radiation facilities over the world. Recently, we constructed a new polarization-controlled X-ray source, the segmented cross undulator, at SPring-8, the largest synchrotron radiation facility in the world. The operation is based on interference of X-ray beams, which is sharply contrast to the conventional method of regulating electron trajectory by the mechanical control of magnets. The paradigm shift opened the measurement innovations and allowed us to design new experimental approaches to capture signals that have been hidden in materials. The present review describes the novel X-ray source with the principle of operation and the technical details of optimization. Examples of the frontier spectroscopies that use unique optical properties of the source are introduced, followed by the future prospects for next generation synchrotron radiation facilities.

Abstract Purpose The aim of the present study was to investigate the effect of glutathione ethyl ester (GSH‐OEt) in the recovery medium on the developmental competence of mouse vitrified‐warmed MII oocytes. Methods Vitrified‐warmed oocytes were incubated for 1 h in recovery medium in the presence or absence of 0.5 mM GSH‐OEt. The authors examined the effects of GSH‐OEt, first on the levels of glutathione (GSH) and reactive oxygen species (ROS) in vitrified‐warmed oocytes, and second, on in vitro blastocyst development, division speed to blastocysts, and total cell numbers of blastocysts from vitrified‐warmed oocytes fertilized by Intracytoplasmic sperm injection (ICSI). Results Adding GSH‐OEt to the recovery medium significantly (p

Background: Luteal phase support (LPS) is essential for hormone replacement therapy (HRT) for frozen-thawedembryo transfer (FET). However, the optimal dose and serum progesterone (P4) levels required for pregnancy arecontroversial. We attempted to determine the association between pregnancy outcomes and serum P4 levels administeredvia 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 prospectivelyinvestigated pregnancy outcomes of four different P4 vaginal suppositories (Lutinus, Utrogestan, Luteum, andCrinone) 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: 13.7 ng/mL). We investigated clinicalpregnancy rate (CPR), positive fetal heart rate (FHR), live birth rate (LBR), and miscarriage rate (MR) for eachgroup. A logistic regression analysis was performed using age, body mass index (BMI), and transferred embryosas 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

Abstract Purpose To investigate the first‐division kinetics and in vitro development of embryos produced by injecting sonicated sperm heads with high or low chromosomal integrity into oocytes. Methods Mouse spermatozoa were frozen after separating the sperm heads from the tails by sonication in an EGTA solution (EGTA group) or M2 medium (M2 group). The chromosomal integrity of sonicated mouse spermatozoa was analyzed by injecting the sperm heads into fresh mouse oocytes. The developmental potential of spermatozoa was examined by injecting the sperm heads into vitrified‐warming mouse oocytes. We used a time‐lapse monitoring system to compare the first‐division kinetics. Results Chromosomal integrity was preserved significantly more frequently in the EGTA group (90.6%) than in the M2 group (32.7%). Blastocysts developed significantly more often in the EGTA group (80.8%) than in the M2 group (39.6%). In the M2 group, with frequent chromosome aberrations, the time between the sperm injection and first cleavage was delayed (18.4 hours), compared to the EGTA group (16.5 hours). All results of the EGTA group were similar to that of fresh epididymal spermatozoa. Conclusion The EGTA solution for sonication maintained the integrity of sperm chromosomes. Our results revealed a relationship between sperm chromosome integrity and first‐division kinetics.

Constant strain rate nanoindentation testing is useful for evaluating local strain rate sensitivity. In titanium alloys, the dwell fatigue at room temperature is a critical issue, and this phenomenon is known as relating to local strain rate sensitivity. We investigate the local strain rate sensitivity of Ti–6242S and IMI834 which are well known heat resistant titanium alloys. Firstly, the validity of strain rate sensitivity by using dynamic nanoindentation testing was verified by measuring the material which has low strain rate sensitivity. Then, rate sensitivity of titanium alloy was examined by nanoindentation testing. Combined with the results from the structural analysis by the electron back scattered diffraction pattern, the factors which affect the strain rate sensitivity are investigated.

Hydrogen-bonded network of water surrounding polymers is expected to be one of the most relevant factors affecting biocompatibility, while the specific hydrogen-bonded structure of water responsible for biocompatibility is still under debate. Here we study the hydrogen-bonded structure of water in a loop-shaped poly(ethylene glycol) chain in a polyrotaxane using synchrotron soft X-ray emission spectroscopy. By changing the density of anchoring molecules, hydrogen-bonded structure of water confined in the poly(ethylene glycol) loop was identified. The XES profile of the confined water indicates the absence of the low energy lone-pair peak, probably because the limited space of the polymer loop entropically inhibits the formation of tetrahedrally coordinated water. The volume of the confined water can be changed by the anchoring density, which implies the ability to control the biocompatibility of loop-shaped polymers.

Abstract Purpose The time‐lapse system is a device that allows continuous monitoring without removing embryos from the incubator. Using a time‐lapse system, we retrospectively investigated cleavage speed time points as potential indicators for selecting high‐quality viable blastocysts. Methods This study included 963 zygotes of two pronuclei retrieved from 196 patients between January 2015 and December 2016. All embryos in culture were monitored by time‐lapse after intracytoplasmic sperm injection. Of 492 blastocysts developed in vitro, 128 vitrified‐warmed single blastocyst transfers were classified into pregnancy and non‐pregnancy groups, and the parameters were compared. Results In the pregnancy group, timing of both morula compaction and regular blastocyst formation was significantly faster than in the non‐pregnancy group. Furthermore, the optimal cutoff values for compacted morula (94.9 hours) and regular blastocyst (113.9 hours) were determined using the receiver operator characteristic curve analysis. Embryos that formed compacted morulae within 94.9 hours and developed into regular blastocysts within 113.9 hours were associated with a significantly higher pregnancy rate than those that did not (44.4% vs 16.0%). Conclusion The timing of morula compaction and regular blastocyst formation is important as an indicator of high‐quality blastocysts to increase odds for pregnancy after embryo transfer.

Abstract In situ high energy resolution fluorescence detection X-ray absorption spectroscopy (HERFD-XAS) was used to systematically evaluate interactions of H2O and O2 adsorbed on Pt and Pt3Co nanoparticle catalysts in different particle sizes. The systematic increase in oxidation due to adsorption of different species (H2O adsorption

Sodium-excess metal oxides Na2MO3 are appealing cathode materials for sodium-ion batteries. Here, the authors demonstrate that honeycomb-type cation ordering in Na2RuO3 triggers the oxygen redox reaction via frontier orbital reorganization, increasing the capacity by 1/3 compared with disordered Na2RuO3.