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New constraints on the composition of Earth’s inner core are provided by experimental verification of Birch’s law for hexagonal close-packed iron to pressure above 300 gigapascals, about double the pressure achieved in previous investigations

Abstract The activity of deep-focus earthquakes, which increases with depth from ~400 km to a peak at ~600 km, is enigmatic, because conventional brittle failure is unlikely to occur at elevated pressures. It becomes increasingly clear that pressure-induced phase transitions of olivine are responsible for the occurrence of the earthquakes, based on deformation experiments under pressure. However, many such experiments were made using analogue materials and those on mantle olivine are required to verify the hypotheses developed by these studies. Here we report the results of deformation experiments on (Mg,Fe)2SiO4 olivine at 11−17 GPa and 860−1350 K, equivalent to the conditions of the slabs subducted into the mantle transition zone. We find that throughgoing faulting occurs only at very limited temperatures of 1100−1160 K, accompanied by intense acoustic emissions at the onset of rupture. Fault sliding aided by shear heating occurs along a weak layer, which is formed via linking-up of lenticular packets filled with nanocrystalline olivine and wadsleyite. Our study suggests that transformational faulting occurs on the isothermal surface of the metastable olivine wedge in slabs, leading to deep-focus earthquakes in limited regions and depth range.

Fragmentation contributes to the formation and evolution of stars. Observationally, high-mass stars are known to form multiple-star systems, preferentially in cluster environments. Theoretically, Jeans instability has been suggested to determine characteristic fragmentation scales, and thermal or turbulent motion in the parental gas clump mainly contributes to the instability. To search for such a characteristic fragmentation scale, we have analyzed Atacama Large Millimeter/submillimeter Array (ALMA) 1.33 mm continuum observations toward 30 high-mass star-forming clumps taken by the Digging into the Interior of Hot Cores with ALMA survey. We have identified 573 cores using the dendrogram algorithm and measured the separation of cores by using the Minimum Spanning Tree technique. The core separation corrected by projection effects has a distribution peaked around 5800 au. In order to remove biases produced by different distances and sensitivities, we further smooth the images to a common physical scale and perform completeness tests. Our careful analysis finds a characteristic fragmentation scale of ∼7000 au, comparable to the thermal Jeans length of the clumps. We conclude that thermal Jeans fragmentation plays a dominant role in determining the clump fragmentation in high-mass star-forming regions, without the need to invoke turbulent Jeans fragmentation.

Fragmentation during the early stages of high-mass star formation is crucial for understanding the formation of high-mass clusters. We investigated fragmentation within 39 high-mass star-forming clumps as part of the Atacama Large Millimeter/submillimeter Array Survey of 70 μ m Dark High-mass Clumps in Early Stages (ASHES) survey. Considering projection effects, we have estimated core separations for 839 cores identified from the continuum emission and found mean values between 0.08 and 0.32 pc within each clump. We find compatibility of the observed core separations and masses with the thermal Jeans length and mass, respectively. We also present subclump structures revealed by the 7 m array continuum emission. Comparison of the Jeans parameters using clump and subclump densities with the separation and masses of gravitationally bound cores suggests that they can be explained by clump fragmentation, implying the simultaneous formation of subclumps and cores within rather than a step-by-step hierarchical fragmentation. The number of cores in each clump positively correlates with the clump surface density and the number expected from the thermal Jeans fragmentation. We also find that the higher the fraction of protostellar cores, the larger the dynamic range of the core mass, implying that the cores are growing in mass as the clump evolves. The ASHES sample exhibits various fragmentation patterns: aligned, scattered, clustered, and subclustered. Using the ${ \mathcal Q }$ -parameter, which can help distinguish between centrally condensed and subclustered spatial core distributions, we finally find that in the early evolutionary stages of high-mass star formation, cores tend to follow a subclustered distribution.

Massive infrared dark clouds (IRDCs) are considered to host the earliest stages of high-mass star formation. In particular, 70 μ m dark IRDCs are the colder and more quiescent clouds. At a scale of about 5000 au using formaldehyde (H _2 CO) emission, we investigate the kinetic temperature of dense cores in 12 IRDCs obtained from the pilot Atacama Large Millimeter/submillimeter Array Survey of 70 μ m dark High-mass clumps in Early Stages (ASHES). Compared to the 1.3 mm dust continuum and other molecular lines, such as C ^18 O and deuterated species, we find that H _2 CO is mainly sensitive to low-velocity outflow components rather than to quiescent gas expected in the early phases of star formation. The kinetic temperatures of these components range from 26 to 300 K. The Mach number reaches about 15 with an average value of about 4, suggesting that the velocity distribution of gas traced by H _2 CO is significantly influenced by a supersonic nonthermal component. In addition, we detect warm line emission from HC _3 N and OCS in 14 protostellar cores, which requires high excitation temperatures ( E _u / k ∼ 100 K). These results show that some of the embedded cores in the ASHES fields are in an advanced evolutionary stage, previously unexpected for 70 μ m dark IRDCs.

We observed the high-mass star-forming core G336.01–0.82 at 1.3 mm and 0.″05 (∼150 au) angular resolution with the Atacama Large Millimeter/submillimeter Array (ALMA) as part of the Digging into the Interior of Hot Cores with ALMA survey. These high-resolution observations reveal two spiral streamers feeding a circumstellar disk at opposite sides in great detail. Molecular line emission from CH _3 OH shows velocity gradients along the streamers consistent with infall. Similarly, a flattened envelope model with rotation and infall implies a mass larger than 10 M _☉ for the central source and a centrifugal barrier of 300 au. The location of the centrifugal barrier is consistent with local peaks in the continuum emission. We argue that gas brought by the spiral streamers is accumulating at the centrifugal barrier, which can result in future accretion burst events. A total high infall rate of ∼4 × 10 ^−4 M _☉ yr ^−1 is derived by matching models to the observed velocity gradient along the streamers. Their contribution accounts for 20%–50% the global infall rate of the core, indicating streamers play an important role in the formation of high-mass stars.

Abstract A coupling device, which can extract coherent edge radiation (CER) from an optical cavity for a free-electron laser (FEL) without damaging the FEL due to diffraction loss, was developed at Nihon University. We successfully observed the CER beam with a power of 1 mW or more in the terahertz range during FEL oscillation. It is revealed that the CER power changed with the detuning of the optical cavity and the dependence of the CER power on the detuning length differs from that of the FEL power. The measured CER spectra indicate that the longitudinal electron distribution in a bunch is modulated by the FEL oscillation with a period corresponding to the FEL slippage length. We herein report the characteristics of the CER with FEL oscillation in detail. These results demonstrate that the CER is excellent tool to reveal the overall effect of FEL interaction on electron distribution in a bunch.

Abstract Background Tetralogy of Fallot is the most common cyanotic congenital heart disease. Patients with the condition have a high risk of developing chronic kidney disease. Treatment of kidney disease in patients with complex hemodynamics presents unique challenges. However, there are very few reports on the treatment of end-stage renal failure in patients with tetralogy of Fallot. Case presentation We present a rare case of peritoneal dialysis in a 47-year-old man with tetralogy of Fallot who had not undergone intracardiac repair. Peritoneal dialysis successfully removed fluids and solutes without adversely affecting the patient’s hemodynamics. Our patient was managed with peritoneal dialysis for 5 years before he succumbed to sepsis secondary to digestive tract perforation. Conclusions In this paper, we discuss the importance of monitoring acid–base balance, changes in cyanosis, and hyperviscosity syndrome during peritoneal dialysis in patients with tetralogy of Fallot. Lower leg edema and B-type natriuretic peptide level were useful monitoring parameters in this case. This case illustrates that with attention to the patient’s unique requirements, peritoneal dialysis can provide successful renal replacement therapy without compromising hemodynamics in patients with tetralogy of Fallot.

Deuterium fractionation in molecules is known as one of the most powerful tools to study chemical processes during star and planet formation. Among various interstellar molecules, methanol often shows very high deuterium fractionation. It is the most abundant saturated organic molecule and is known as a parent species to form more complex organic molecules. However, deriving the abundance of deuterated methanol suffers from the uncertainty in the intrinsic line intensities ( S μ ^2 ) of CH _3 OH isotopologues. Due to their floppy nature, theoretical evaluation of the S μ ^2 values is not straightforward, particularly for asymmetric-top asymmetric-frame isotopologues such as CH _2 DOH. In this study, we have measured the line frequencies and their intensities for CH _2 DOH in the millimeter-wave region from 216 to 264 GHz by using an emission-type millimeter and submillimeter-wave spectrometer. For the a -type J = 5 − 4 transition, the derived S μ ^2 values are 13%–27% larger than those theoretically calculated, except for the transitions of K _a = 2 for e _0 and K _a = 1 for e _1 affected by avoided level crossing. For b -type transitions, significant systematic differences are found between theoretical and experimental S μ ^2 values. The results of the present study enable us to accurately derive from observations the CH _2 DOH abundances, which are essential for understanding deuterium fractionation in various sources.

The initial conditions found in infrared dark clouds (IRDCs) provide insights on how high-mass stars and stellar clusters form. We have conducted high-angular resolution and high-sensitivity observations toward thirty-nine massive IRDC clumps, which have been mosaicked using the 12 and 7 m arrays from the Atacama Large Millimeter/submillimeter Array. The targets are 70 μ m dark massive (220–4900 M _⊙ ), dense (>10 ^4 cm ^−3 ), and cold (∼10–20 K) clumps located at distances between 2 and 6 kpc. We identify an unprecedented number of 839 cores, with masses between 0.05 and 81 M _⊙ using 1.3 mm dust continuum emission. About 55% of the cores are low-mass (

Lignin monomers have attracted attention as functional materials for various industrial uses. However, it is challenging to obtain these monomers by degrading polymerized lignin due to the rigid ether linkage between the aromatic rings. Here, we propose a novel approach based on molecular vibrational excitation using infrared free electron laser (IR-FEL) for the degradation of lignin. The IR-FEL is an accelerator-based pico-second pulse laser, and commercially available powdered lignin was irradiated by the IR-FEL under atmospheric conditions. Synchrotron-radiation infrared microspectroscopy analysis showed that the absorption intensities at 1050 cm−1, 1140 cm−1, and 3400 cm−1 were largely decreased alongside decolorization. Electrospray ionization mass chromatography analysis showed that coumaryl alcohol was more abundant and a mass peak corresponding to hydrated coniferyl alcohol was detected after irradiation at 2.9 μm (νO-H) compared to the original lignin. Interestingly, a mass peak corresponding to vanillic acid appeared after irradiation at 7.1 μm (νC=C and νC-C), which was supported by our two-dimensional nuclear magnetic resonance spectroscopy analysis. Therefore, it seems that partial depolymerization of lignin can be induced by IR-FEL irradiation in a wavelength-dependent manner.

We investigated the transmission characteristics of formalin fixed human liver samples in which normal liver tissue and malignant liver tumor were mixed using terahertz (THz) coherent synchrotron radiation at an infrared free-electron laser (FEL) facility at Nihon University. Infrared-FEL imaging has indicated that the amount of water molecules in the tumor tissue is not different from that in the normal tissue. However, the transmission of the incipient tumor tissue was lower than that of the normal tissue in THz imaging because the tumor tissue contained more water molecular clusters than the normal tissue. The tumor tissue became more permeable owing to the development of fibrous tissue around it. THz imaging will be more useful for discriminating liver tissues by increasing the spatial resolution.

Pancreatic metastasis from prostate cancer (PC) is quite rare. Herein, we report the case of a 67-year-old man with pancreatic metastasis from a neuroendocrine differentiated PC (NEDPC), a local recurrence after radical prostatectomy and androgen deprivation therapy for 6 years. Chemoradiotherapy was initiated for the locally recurrent NEDPC, and it had almost disappeared after the therapy. However, rapidly enlarged pancreatic metastasis from the NEDPC was detected 6 months after therapy. There is no standard treatment available for pancreatic metastasis from NEDPC owing to its rarity; hence, further knowledge and clinical experience regarding it are crucial.

Methanol (CH _3 OH) is an abundant interstellar species and is known to be an important precursor of various interstellar complex organic molecules. Among the methanol isotopologues, CH _2 DOH is one of the most abundant isotopologues and it is often used to study the deuterium fractionation of CH _3 OH in interstellar medium. However, the emission lines of CH _2 DOH can sometimes be optically thick, making the derivation of its abundance unreliable. Therefore, observations of its presumably optically thin ^13 C substituted species, ^13 CH _2 DOH, are essential to overcome this issue. In this study, the rotational transitions of ^13 CH _2 DOH have been measured in the millimeter-wave region from 216 GHz to 264 GHz with an emission-type millimeter- and submillimeter-wave spectrometer by using a deuterium and ^13 C enriched sample. The frequency accuracy of measured ^13 CH _2 DOH is less than a few kHz, and the relative line intensity error is less than 10% in most of the frequency range by taking advantage of the wide simultaneous frequency-coverage of the emission-type spectrometer. These results offer a good opportunity to detect ^13 CH _2 DOH in space, which will allow us to study the deuterium fractionation of CH _3 OH in various sources through accurate determination of the CH _2 DOH abundance.

Duodenal and rectal obstructions due to urological malignancies are relatively uncommon. We report an autopsy case of an 83-year-old man with a history of renal pelvic cancer who presented these obstructions. Autopsy revealed that urothelial cancer infiltrated the bladder wall, duodenal wall, rectal wall, and prostate and widely spread in the retroperitoneal lymphatic vessel. We concluded that renal pelvic cancer recurred in the bladder wall and then infiltrated into each organ because of lymphatic dissemination. The gastrointestinal obstructions due to urinary tract cancer were lethal. Further knowledge and clinical experience regarding these types of obstructions are crucial. Keywords: Duodenal obstruction, Lymphatic dissemination, Rectal obstruction, Urothelial carcinoma

Abstract The phase and melting relations in the Fe–S–Si system were determined up to 60 GPa by using a double-sided laser-heated diamond anvil cell combined with X-ray diffraction. On the basis of the X-ray diffraction patterns, we confirmed that hcp/fcc Fe–Si alloys and Fe3S are stable phases under subsolidus conditions in the Fe–S–Si system. Both solidus and liquidus temperatures are significantly lower than the melting temperature of pure Fe and both increase with pressure. The slopes of the Fe–S–Si liquidus and solidus curves determined here are smaller than the adiabatic temperature gradients of the liquid cores of Mercury and Mars. Thus, crystallization of their cores started at the core–mantle boundary region.

Cerebral infarction in patients with cancer is often called Trousseau's syndrome, which is a cancer-associated hypercoagulative state that causes thrombosis; however, the syndrome is rarely caused by bladder cancer. We report a case of Trousseau's syndrome manifesting as multiple cerebral infarctions caused by advanced bladder cancer in a 46-year-old male patient. The patient died due to the infarctions in the hospital. The prognosis of patients with Trousseau's syndrome caused by advanced cancer is poor. According to changing urological clinical settings, considering the risk of Trousseau's syndrome has become crucial for urologists treating patients with advanced cancer. Keywords: Bladder cancer, Cerebral infarction, Trousseau's syndrome, Urothelial cancer

Purpose: This study aims to develop a self-reflection scale useful for teachers to improve their skills and to clarify the Japanese teachers' characteristics during mathematics lesson observation (MLO). In MLO, it is important to understand the lesson plan in advance to clarify observation points, and we aim to develop a scale including these points. Design/methodology/approach: Based on the pre-questionnaire survey, nine perspectives and two situations for MLO were extracted. From these, a questionnaire for MLO was created. The results obtained from 161 teachers were examined, and exploratory factor analysis was conducted. ANOVA was conducted to analyze the effect of differences across the duration of teaching experience on the identified factors. Findings: We developed a self-reflection scale consisting of 14 items with three factors: [B1] focus on instructional techniques and evaluation, [B2] focus on proactive problem-solving lesson development and [B3] focus on the mathematical background of the learning content. While duration of teaching experience showed no effect, three factors of the self-reflection scale for MLO showed a significant effect. Further multiple comparisons revealed the degree of focus was [B2]>[B1]>[B3]. Originality/value: Teachers who use this developed scale may grasp the strengths and weaknesses of their own MLO, which leads to self-improvement. The perspectives emphasized in lesson observation are the same when creating lesson plans and implementing lessons, leading to lesson improvement. Furthermore, based on the characteristics of teachers revealed, new training programs regarding MLO can lead to higher-quality lesson studies.

This study presents a novel technology to measure electron bunch length with a high time resolution by measuring coherent synchrotron radiation using a narrow-band detector at Laboratory for Electron Beam Research and Application (LEBRA)—an S-band linear accelerator facility for free-electron lasers. The form factor was observed to decrease exponentially with charge—in concordance with the relationship between the intensity of the coherent synchrotron radiation and the magnitude of electron bunch charge—in the region in which the effect of electron bunch charge on bunch length is negligible. The calculated root-mean-square bunch length was observed to agree well with the value determined from the spectral shape obtained. The aforementioned results are expected to be useful in real-time observation of small changes in electron bunches in advanced accelerators.

The pressure effect on the Nèel temperature TN of DyB6 has been investigated by measuring the temperature dependence of electrical resistivity (ρ) at various pressures up to 8 GPa. It was found that TN increases almost linearly with pressure in the range of 0-2 GPa and then tends to saturate above 2 GPa. The pressure derivative of TN below 2 GPa was estimated to be 2.6 K/GPa. The pressure effect on the volume of DyB6 has also been measured at high pressure up to 14 GPa at room temperature using X-ray diffraction and diamond anvil cell. The pressure dependence of volume of LaB6 was also measured for the comparison. It is revealed that DyB6 is more compressible than LaB6. The origin for this observation is suggested to be due to the difference of the ionic size of the rare earth elements, or the strong electron-phonon interaction in DyB6.