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The phreatic eruption is one of the volcanic eruption styles triggered by the rapid vaporization of heated fluids at shallow depth without the involvement of juvenile magma (e.g., Stix and deMoor [23]). 10.1186/s40623-021-01468-3 5 Kataoka KS, Tsunematsu K, Matsumoto T. Crisis hazard assessment for snow-related lahars from an unforeseen new vent eruption: the 2018 eruption of Kusatsu-Shirane volcano, Japan. Papers on the Kusatsu-Shirane volcano Kusatsu-Shirane volcano is an active dacite-andesite Quaternary volcano located in Gunma Prefecture, Central Japan. After the onset of the 2010 phreatic eruption of the Turrialba volcano, the underlying geothermal system changed as seen from the significant increase in the fumarole output at the Turrialba volcano. [Extracted from the article]

Gufoni maneuver is known to be effective for horizontal canal benign positional vertigo (HC-BPPV), but there are some intractable patients that the treatment procedure does not work. The clinical outcomes of patients with HC-BPPV were investigated. We also investigated the characteristics of intractable patients which needed long time to the remission. Sixty-six patients with HC-BPPV receiving Gufoni maneuver at Tokyo Medical University Hachioji Medical Center were investigated. The patients were classified into geotropic DCPN group and apogeotropic DCPN group. The clinical outcomes in 2 groups were examined. There were 48 patients with geotropic DCPN and 18 patients with apogeotropic DCPN. There were significant differences between the geotropic HC-BPPV and apogeotropic HC BPPV in the period to remission. There were 7 intractable patients and the average ages of these intractable patients were higher than other patients. The patients with geotropic DCPN and the patients with the nystagmus conversion from apogeotropic to geotropic DCPN have tendency to easy to resolve, but in patients with apogeotropic type without nystagmus transformation have long time to resolve. The elderly patients whose nystagmus remains apogeotropic without nystagmus conversion have tendencies to become intractable. [ABSTRACT FROM AUTHOR]

Fluids within the Earth's crust may exist under supercritical conditions (i.e., >374°C and >22.1 MPa for pure water). Supercritical geothermal reservoirs at depths of 2–10 km below the surface in northeastern (NE) Japan mainly consist of magmatic fluids that exsolved from the melt during the course of fractional crystallization. Supercritical geothermal reservoirs have received attention as next‐generation geothermal resources because they can offer significantly more energy than that obtained from conventional geothermal reservoirs found at temperatures <350°C. However, the spatial distribution and fluid fraction of supercritical geothermal reservoirs, which are required for their resource assessment, are poorly understood. Here, the magnetotelluric (MT) method with electrical resistivity imaging is used in the Yuzawa geothermal field, NE Japan, to collect data on the fluid fraction and spatial distribution of a supercritical geothermal reservoir. The collected MT data reveal a potential supercritical geothermal reservoir (>400°C) with dimensions of 3 km (width) × 5 km (length) at a depth of 2.5–6.0 km below the surface. The estimated fluid fraction of the reservoir is 0.1%–4.2% with salinity values of 5–10 wt%. The melt is also imaged below the reservoir, and based on the resistivity model; we develop a mechanism for the evolution of the supercritical geothermal reservoir, wherein upwelling supercritical fluids supplied from the melt are trapped under less permeable silica sealing and accumulate there. Plain Language Summary: As the demand for sustainable energy solutions has increased worldwide, geothermal energy has emerged as a clean and renewable energy source that comes from reservoirs of hot water beneath the Earth's surface. Subsurface fluids in a supercritical state (high temperature and pressure) have received attention as the next‐generation geothermal resources because they can offer significantly more energy than that obtained from conventional geothermal fluids found at temperatures <350°C. Supercritical geothermal fluids are located in various volcanic areas in the world. However, understanding of the spatial distribution and fluid fraction of supercritical fluids, which is necessary for their resource assessment, is limited. Therefore, we use the magnetotelluric (MT) method to obtain information on the spatial distribution and fluid fraction of a supercritical geothermal reservoir in the Yuzawa geothermal field in northeastern Japan. The MT method is sensitive to the subsurface electrical resistivity distribution, which in turn can be used as a proxy for the presence of supercritical fluids. The collected MT data reveal a potential supercritical geothermal reservoir of 3 km (width) × 5 km (length) at a depth of 2.5–6 km below the surface with a fluid fraction of 0.1%–4.2% and salinity of 5–10 wt%. Key Points: A supercritical geothermal reservoir of 3 km (width) × 5 km (length) is imaged using the magnetotelluric method at a depth of 2.5–6.0 kmThe fluid fraction of the supercritical reservoir is estimated to be 0.1%–4.2% with salinity of 5–10 wt%Upwelling supercritical fluids supplied from the melt are trapped under a less‐permeable silica sealing [ABSTRACT FROM AUTHOR]

Objective: The vestibular evoked myogenic potential (VEMP) is associated with otolithic afferents and can be used to evaluate the function of the saccule and utricle. In this study, we compared cervical VEMP evoked by stimulation with Air-conducted sound (ACS) and bone-conducted vibration (BCV) to the forehead and investigated whether BCV can be used as a substitute for ACS. Methods: Data were obtained from 33 patients with vestibular schwannoma. Vestibular examinations were performed preoperatively. VEMP was obtained upon stimulation with ACS (ACS cVEMP) and BCV to the forehead using a minishaker (BCV cVEMP). Vestibular function was also analyzed using the caloric test and ocular VEMP (oVEMP) testing. oVEMP was measured using bone-conductive vibration to the forehead. The results of BCV cVEMP, ACS cVEMP, and oVEMP were compared by the caloric test. Results: Rates of patients with abnormal ACS cVEMP, BCV cVEMP, oVEMP, and caloric test results were 78.8%, 75.8%, 78.8%, and 69.7%, respectively. BCV cVEMP did not correlate with ACS cVEMP, but correlated with oVEMP and caloric test results. Conclusion: BCV cVEMP did not correlate with ACS cVEMP. Therefore, BCV cVEMP cannot be used as a substitute for ACS cVEMP. [ABSTRACT FROM AUTHOR]

People whom the author would like to thank for their assistance in the creation of the periodical "Earth, Planets & Space."

People whom the author would like to thank for their assistance in evaluating the papers for the journal "Earth, Planets and Space" are mentioned.

Conclusions: The co-existence of cupulolithiasis and canalolithiasis might be a possible mechanism for the spontaneous inversion of positional nystagmus. Objective: To investigate the mechanism of spontaneous inversion of nystagmus direction without a positional change in experimental models of co-existing cupulolithiasis and canalolithiasis. Methods: Co-existing canalolithiasis and cupulolithiasis models were prepared using the bullfrog posterior semicircular canal (PSC). Ten bullfrogs were used. The ampullary nerve discharges were recorded as compound action potentials (CAPs). First, an otoconial mass was placed on the cupula to produce cupulolithiasis. Subsequently, another otoconial mass was introduced into the canal lumen to produce canalolithiasis. Decremental time constants for cupulolithiasis and incremental time constants for canalolithiasis were determined. Results: At first the CAPs increased and continued for a long time when the cupulolithiasis was generated. Subsequently the CAPs were suppressed by creating canalolithiasis. Finally, the CAPs increased again after the motion of otoconia inside the canal lumen stopped. The decremental time constant for cupulolithiasis was significantly longer than the incremental time constant for canalolithiasis. [ABSTRACT FROM AUTHOR]

The white line in c denotes the projection of fumarole zone F1 at 1400 m ASL. d The 3-D view of the three major conductors. The white, black and gray dots denote hypocenters before, during and after the 2014 unrest, respectively. Correction to: Anatomy of active volcanic edifice at the Kusatsu-Shirane volcano, Japan, by magnetotellurics: hydrothermal implications for volcanic unrests. [Extracted from the article]

Abstract: Intermittent positional down beat nystagmus (p-DBN) is rare. We describe an unusual case of intermittent p-DBN which was induced by rotation, anteflexion, and lateral flexion of the neck. A 59-year-old man complained of loss of consciousness and lightheadedness. Positional testing revealed the p-DBN. The evoked p-DBN had latency and the patient had a feeling of passing out while the p-DBN was present. There were no abnormal findings in the vestibular functional examinations. Findings of the MRI were negative. MRA revealed no stenosis of the vertebral artery bilaterally, but there was an anatomical difference. The p-DBN characteristics were documented by electronystagmography during the positional test. The p-DBN lasted intermittently while maintaining the provoking position. It was found that p-DBN occurred with not only the rotation of the neck, but also in the anteflexion and lateral flexion of the neck. There was no stenosis of the vertebral artery (VA) on angiography, but we speculated that the cause of the p-DBN was the VA occlusion due to rotation, anteflexion, and lateral flexion of the neck. [Copyright &y& Elsevier]

Conclusion: Patients with vestibular neuritis (VN) with complete canal paresis (CP) showed a higher rate of abnormal ocular vestibular evoked myogenic potential (oVEMP) than those with partial CP. From these results, it is speculated that the superior vestibular nerve function mainly affects oVEMP. Significant correlation was found between the grades of the hearing outcome and oVEMP in sudden sensorineural hearing loss (SSHL). Objective: We attempted to correlate the results of oVEMP with the results of cervical VEMP (cVEMP), results of subjective visual vertical (SVV), and clinical course in patients with various vestibular disorders. Methods: Twenty-two patients with VN, 65 with SSHL, and 22 with Meniere's disease (MD), were enrolled in this study. We compared the results of oVEMP with those of cVEMP, SVV, and the caloric test. Furthermore, the oVEMP results were compared with the initial hearing threshold, presence of vertigo, and hearing recovery in the patients with SSHL. Results: The patients with VN with complete CP showed a higher rate of abnormal oVEMP than those with partial CP. In the patients with SSHL, the hearing recovery rate was lower in the patients with abnormal oVEMP than in those with normal oVEMP. [ABSTRACT FROM AUTHOR]

Objective: To determine the subjective visual vertical (SVV) perception in patients with vestibular neuritis (VN) and sudden sensorineural hearing loss (SSHL) using the SVV test and other neuro-otological examinations, namely, the vestibular evoked myogenic potential (VEMP) and caloric tests, and to clarify which vestibular nerve function is associated with an SVV shift. Patients and methods: We performed the SVV test in 36 VN patients and 80 SSHL patients. Thereafter, we investigated directional changes in the SVV in the VN and SSHL patients, and compared the results of the SVV test with those of the VEMP and caloric tests. Results: Abnormal SVV (> 2° was found at a rate of 69.4% in the VN patients and 26.3% in the SSHL patients. In all except 1 VN patient, the SVV tilted to the lesion side. The rate of abnormal SVV was significantly higher in patients with complete canal paresis (CP) than in patients with partial CP. There was no significant relationship between the rates of abnormal SVV and VEMP. In the SSHL patients, neither the SVV nor the VEMP affected the hearing outcome and patients with abnormal VEMP tended to show abnormal SVV. Conclusion: VN patients showed a higher rate of abnormal SVV than SSHL patients. From the results, it is speculated that the superior vestibular nerve function mainly affects the SVV tilt, although the inferior vestibular nerve function may also have an effect. [ABSTRACT FROM AUTHOR]

Conclusion: Dysequilibrium is one of the most important side effects of ear surgery. The subjective visual vertical can be used as a good indicator for the evaluation of otolithic function in patients with ear surgery. Objective: To investigate the influence of various types of ear surgery on the otolithic organs. Methods: Seventy-one patients underwent ear surgery. Subjective visual vertical (SVV) test was performed before and after ear surgery. We investigated the directional changes of SVV before and after the ear surgery. Results: The postoperative SVV of two patients who underwent translabyrinthine removal of vestibular schwannoma shifted toward the operated side, but following other surgical procedures the SVV tended to shift toward the healthy side. [ABSTRACT FROM AUTHOR]

Abstract: We report the clinical features of 4 cases with positional or positioning down-beating nystagmus in a head-hanging or supine position without any obvious central nervous system disorder. The 4 cases had some findings in common. There were no abnormal findings on neurological tests or brain MRI. They did not have gaze nystagmus. Their nystagmus was observed only in a supine or head-hanging position and it was never observed upon returning to a sitting position and never reversed. The nystagmus had no or little torsional component, had latency and tended to decrease with time. The positional DBN (p-DBN) is known to be indicative of a central nervous system disorder. Recently there were some reports that canalithiasis of the anterior semicircular canal (ASC) causes p-DBN and that patients who have p-DBN without obvious CNS dysfunction are dealt with anterior semicircular canal (ASC) benign paroxysmal positional vertigo (BPPV). There are some doubts as to the validity of making a diagnosis of ASC-BPPV in a case of p-DBN without CNS findings. It is hard to determine the cause of p-DBN in these cases. [Copyright &y& Elsevier]

Abstract: Magnetotelluric (MT) measurements were conducted at Iwate volcano, across the entirety of the mountain, in 1997, 1999, 2003, 2006, and 2007. The survey line was 18km in length and oriented E–W, comprising 38 measurements sites. Following 2D inversion, we obtained the resistivity structure to a depth of 4km. The surface resistive layer (~several hundreds of meters thick) is underlain by extensive highly conductive zones. Based on drilling data, the bottom of the highly conductive zone is interpreted to represent the 200°C isotherm, below which (i.e., at higher temperatures) conductive clay minerals (smectite) are rare. The high conductivity is therefore mainly attributed to the presence of hydrothermally altered clay. The focus of this study is a resistive body beneath the Onigajo (West-Iwate) caldera at depths of 0.5–3km. This body appears to have impeded magmatic fluid ascent during the 1998 volcanic unrest, as inferred from geodetic data. Both tectonic and low-frequency earthquakes are sparsely distributed throughout this resistive body. We interpret this resistive body as a zone of old, solidified intrusive magma with temperatures in excess of 200°C. Given that a similar relationship between a resistive body and subsurface volcanic activity has been suggested for Asama volcano, structural controls on subsurface magmatic fluid movement may be a common phenomenon at shallow levels beneath volcanoes. [Copyright &y& Elsevier]

Abstract: Asama volcano is an active volcano with many historical records of Vulcanian eruptions. Its most recent eruptions occurred in 2004 at the summit crater. In this paper, we argue the resistivity structure shallower than 3 km obtained by a dense magnetotelluric survey. The magnetotelluric data were obtained at 74 measurement sites mainly along the four survey lines across the volcano. The resistivity profiles obtained by two-dimensional inversions are characterized by a resistive surface layer and an underlying conductive layer. The dominant feature of the profiles is the existence of resistive bodies at a depth range of a few hundred meters to a few kilometers surrounded by a highly conductive region. Considering that the location of resistive bodies correspond to the old eruption centers (one corresponds to the 24 ka collapse caldera and the other to the 21 ka lava dome), the resistive bodies imply zones of old and solidified intrusive magma with low porosity. Because geothermal activities exist near the resistive bodies, the enclosing highly conductive regions are interpreted as a hydrothermal system driven by the heat from the old solidified magma. Beneath the resistive body under the collapsed caldera, intrusion of magma is inferred from the studies of volcano-tectonic earthquakes and continuous global positioning system (GPS) observation, implying the structural control of magma activity within the volcano. In this study, we propose that the magma ascent was impeded by the old and solidified remnant magma and partly migrated horizontally to the east and finally ascended to the summit, resulting in the 2004 eruptions. [Copyright &y& Elsevier]

Abstract: Ryanodine receptor (RyR) is the Ca2+-induced Ca2+ release channel in cells. RyR1 and RyR2 are its isoforms expressed in the skeletal and cardiac muscles, respectively. Their missense mutations, which are clustered in three regions that correspond to each other, cause hereditary disorders such as malignant hyperthermia and central core disease in skeletal muscle and catecholaminergic polymorphic ventricular tachycardia in cardiac muscle. Their pathogeneses, however, are not well understood. The following hypotheses are favorably discussed in this article: phenotypes with RyR1 and RyR2 mutations are mainly caused by dysregulations of their functions through the interdomain interaction and luminal Ca2+, respectively. [Copyright &y& Elsevier]

Abstract: We report a 37-year-old woman with acute disseminated encephalomyelitis (ADEM) who presented with progressive vertigo. A central nervous system disorder was initially suspected because gaze-evoked torsional nystagmus was observed and electrical nystagmography (ENG) revealed abnormal eye movements with saccadic ocular pursuit and pathological optokinetic nystagmus. Finally ADEM was diagnosed by the clinical symptoms and the characteristic patterns of brain MRI. It is rare for otolaryngologists to examine patients with ADEM. ADEM takes an acute course and can present a grave state and therefore needs early diagnosis, early treatment. We have to keep ADEM in mind in the diagnosis of vertigo. [Copyright &y& Elsevier]

Several thin films of single‐walled carbon nanotube (SWCNT) were prepared on ITO glasses by electrolytic micelle disruption methods using surfactants bearing a ferrocenyl moiety (1a and 1b). Surfactant 1a has a polyethylene glycol unit as the hydrophilic moiety, while surfactant 1b has an ammonium salt unit. The surfaces of the resulting films formed by the electrolysis methods were confirmed by SEM and AFM measurements, and then these images clearly exhibited that the entire surface of the ITO glass was uniformly covered with SWCNT. The thicknesses of the resulting films were estimated by the SEM images of cross‐sections of the film. For example, the thickness of the film formed by the electrolysis for 12 hours was ca. 4500 Å. Besides the SEM images of the cross‐sections of the resulting films, the UV‐Vis spectroscopy showed clearly that the film thickness increased with electrolysis time. The photovoltaic performance of dye‐sensitized solar cells (DSCs) using the resulting thin films as a counterelectrode material instead of a common platinized counterelectrode was investigated. As a result, the highest solar‐to‐electric energy conversion efficiency among the present investigations was found to be obtained in the case with the thin film formed by the electrolysis with surfactant 1a for 36 hours. [ABSTRACT FROM AUTHOR]

Abstract: WINDS is the experimental communications satellite currently under joint development by Japanese Aerospace Exploration Agency (JAXA) and the National Institute of Information and Communications Technology (NICT). The high-speed satellite communication system is very effective for quick deployment of high-speed networks economically. The WINDS will realize ultra high-speed networking and demonstrate operability of satellite communication systems in high-speed internet. NICT is now developing high-speed satellite communication system for WINDS. High-speed TDMA burst modem with high performance TPC error correction is underdevelopment. Up to the DAC on the transmitter and from the ADC on the receiver, all modem functions are performed in the digital processing technology. Burst modem has been designed for a user data rate up to 1244Mbps. NICT is developing the digital terminal as a user interface and a network controller for this earth station. High compatibility with the Internet will be provided. [Copyright &y& Elsevier]

Abstract: Several thin films of [60]fullerene and the derivatives (3–5) have been prepared on ITO glasses by a common coating method using organic solutions and/or by an electrolytic micelle disruption method using surfactants with ferrocenyl moiety 2. In particular, the surface of the film formed by the electrolysis method was confirmed by SEM and AFM measurements, and then these images clearly exhibited that the entire surface of the ITO glass was uniformly covered with [60]fullerene. The UV–vis spectroscopy obviously showed that the thickness increased with the electrolysis time. For example, the thickness of the film formed by the electrolysis for 2h was ca. 2,000Å. Furthermore, we investigated the potential utilization as a counter electrode material instead of Pt in a dye-sensitized solar cell (DSC). Consequently, these films, except for that of derivative 5 prepared by the coating process, were found to act as a counter electrode materials in a DSC. These photovoltaic efficiencies of the films prepared by the electric micelle disruption method were higher than those of the films prepared by the common coating method. In addition, the highest efficiency was obtained in the cases with the fullerene thin film formed by the electrolysis for 2h. [Copyright &y& Elsevier]

Abstract: It has long been recognized that the Kii Peninsula in the southwest Japan arc is peculiar in a non-volcanic region, indicated by the presence of high temperature hot springs, high terrestrial heat flow and high 3He content in hot spring gases. Geophysical and geochemical studies were carried out to understand the geotectonic environment in the southern part of the Kii Peninsula. Most of the measured 3He/ 4He ratios are similar or higher than air, indicating wide spread incorporation of mantle-derived helium into meteoric water. A region with rather high 3He/ 4He ratios (>4 RA) on the west side of the Omine Mountains coincides with the occurrence of high temperature hot springs. A deep crustal resistivity structure across the Omine Mountains was imaged by wide-band magnetotelluric soundings. A 2-D inversion with N–S strike using both TM and TE modes reveals two conductors, one in the upper (3–7 km depth) and the other in lower crust (25–35 km depth) to the west of the Omine Mountains. The distribution of microearthquakes and low-frequency tremors, and the existence of seismic reflectors indicate that the large conductor in the lower crust is related to aqueous fluids derived from the Philippine Sea plate. The upper-crustal conductive zone may also reflect the aqueous fluids trapped in the upper crust, which are presumably derived from the subducting slab. Considering the occurrence of seismic events in the subducting slab beneath the southern Kii Peninsula, the aqueous fluids generated by dehydration of the slab mantle could plausibly include MORB-type helium derived from the residual lithospheric mantle. Therefore, the high temperature hot springs and high 3He emanations in hot spring gases and other geotectonic events in the southern Kii Peninsula may be due to heat flux and mantle-derived helium discharged from aqueous fluid in the upper crust. [Copyright &y& Elsevier]

We showed that frog α-ryanodine receptor (α-RyR) had a lower gain of Ca2+-induced Ca2+ release (CICR) activity than β-RyR in sarcoplasmic reticulum (SR) vesicles, indicating selective "stabilization" of the former isoform (Murayama T and Ogawa Y. J Biol Chem 276: 2953-2960, 2001). To know whether this is also the case with mammalian RyR1, we determined [³H]ryanodine binding of RyR1 and RyR3 in bovine diaphragm SR vesicles. The value of [³H]ryanodine binding (B) was normalized by the number of maximal binding sites (Bmax), whereby the specific activity of each isoform was expressed. This B/Bmax expression demonstrated that ryanodine binding of individual channels for RyR1 was <15% that for RyR3. Responses to Ca2+, Mg2+, adenine nucleotides, and caffeine were not substantially different between in situ and purified isoforms. These results suggest that the gain of CICR activity of RyR1 is markedly lower than that of RyR3 in mammalian skeletal muscle, indicating selective stabilization of RyR1 as is true of frog α-RyR. The stabilization was partly eliminated by FK506 and partly by solubilization of the vesicles with CHAPS, each of which was additive to the other. In contrast, high salt, which greatly enhances [³H]ryanodine binding, caused only a minor effect on the stabilization of RyR1. None of the T-tubule components, coexisting RyR3, or calmodulin was the cause. The CHAPS-sensitive intra- and intermolecular interactions that are common between mammalian and frog skeletal muscles and the isoform-specific inhibition by FKBP12, which is characteristic of mammals, are likely to be the underlying mechanisms. [ABSTRACT FROM AUTHOR]

It is generally impossible to exchange, repair, or upgrade onboard equipment in orbit, and communications satellites are designed for fifteen or more years of life. Consequently, orbiting communications satellites cannot follow unforeseen changes in terrestrial communications. Moreover, because of long lead times and high costs of satellite development, it is difficult to implement the latest technology at launch. And even if the latest communications technology were implemented at the time of launch, the configuration on orbit has limited capability for configuration change to parallel the endless evolution in terrestrial communications technology. In this paper, we propose a reconfigurable communication satellite system based on formation flying and inter-satellite communications technology. The satellite is composed of a group of satellites. The functions implemented by each satellite are defined by the OSI (Open Systems Interconnection) reference model. The discussion centers on a three satellite constellation or cluster having relatively close spacing; but the concept may be applied to larger clusters and spacings. Satellites implementing higher OSI layers are small and also on a size reducing trend. Replacing or adding small satellite elements might enable the cluster as a whole to keep pace with frequent paradigm shifts of terrestrial networks. [ABSTRACT FROM AUTHOR]

Ryanodine receptor (RyR) is a Ca2+ release channel in the sarcoplasmic reticulum and plays an important role in excitation–contraction coupling in skeletal muscle. The Ca2+ release through the RyR channel can be gated by two distinct modes: depolarization-induced Ca2+ release (DICR) and Ca2+-induced Ca2+ release (CICR). Two different RyR isoforms, RyR1 (or α-RyR) and RyR3 (or β-RyR), have been found to be expressed in skeletal muscle. Most adult mammalian muscles express primarily RyR1, whereas almost equal amounts of the two RyR isoforms exist in many nonmammalian vertebrate muscles. RyR1 is believed to be responsible for both DICR and CICR, whereas RyR3 may function as the CICR channel. Recent findings demonstrate that α-RyR is selectively and markedly suppressed in CICR activity in frog skeletal muscle. This selective suppression of RyR1, although to a lesser extent, also was found to occur in mammalian skeletal muscle. This short review describes the biological meanings of this selective suppression and discusses physiological roles and significance of the two RyR isoforms in vertebrate skeletal muscle. [Copyright &y& Elsevier]

• We studied MT imaging of a deep conductor using synthetic models. • We used simplified models of a potential supercritical geothermal system. • We found that the MT method can image a conductor of supercritical fluids. • If a vertically elongated conductor is imaged, the actual bottom part may be wider. • A deep conductor in the Kakkonda area is potentially related to supercritical fluids. Fluids trapped under supercritical conditions are potential geothermal resources yielding high well-productivity. These supercritical fluids may be imaged as deep conductors (> 2km depth) using the magnetotelluric (MT) method. However, MT imaging of a deep conductor is strongly dependent on the conductor geometries and the overlying clay layers. The ability of the MT method to image a deep conductor needs clarification to understand the usefulness of MT for exploring supercritical fluids and accurately relate the imaged conductor to supercritical fluids. In this study, we investigated MT imaging of a deep conductor of supercritical fluids using numerical tests, based on a conceptual resistivity model for a supercritical geothermal system in the Kakkonda area, northeast Japan. The test result showed that the MT method was able to image the deep conductor of supercritical fluids. However, we found that the shape and resistivity value of the imaged deep conductor might significantly differ from those of the true conductor. Specifically, if a deep vertically elongated conductor is imaged by MT inversion, it is necessary to be aware that the actual bottom part may be much wider in the horizontal directions than the imaged size. [ABSTRACT FROM AUTHOR]

Investigates the underlying mechanisms of the contraction of skinned smooth muscle (SM). Preparation of skinned samples; Tension measurements; Phosphopeptide mapping; Acidic treatment with adenosine diphosphate (ADP).

Objective: To analyze the preoperative patterns of caloric test, eye tracking test (ETT), and optokinetic pattern (OKP) in patients with acoustic neuroma (AN) and compare them with the postoperative patterns of ETT and OKP results METHODS: A total of 166 patients with AN (102 women; mean age: 41 years, range: 11-79 years) who were being treated at our hospital between 2013 and 2016 were enrolled. Preoperatively, a detailed history was taken regarding the presence of subjective symptoms of equilibrium dysfunction, and the patients underwent caloric test, ETT, and OKP. They were classified into three groups based on the preoperative ETT and OKP results as follows: Group A, normal ETT and OKP; Group B, either ETT or OKP was abnormal; and Group C, both ETT and OKP were abnormal. All patients were evaluated for subjective symptoms of vestibular dysfunction and were also grouped based on the tumor size on imaging. All surgeries were performed by a neurosurgeon using the lateral suboccipital retrosigmoid approach. About one month later after surgery, postoperatively ETT was performed on 150 patients and OKP was performed on 148 patients. The preoperative and postoperative ETT and OKP results were compared. The same two specialists analyzed the postoperative ETT and OKP findings as improved, unchanged, or worse. Student t-test was used for statistical analysis and a P-value of <0.05 was considered to indicate a statistically significant difference.Results: The average canal paresis(CP) % was 65.8%. No correlation was found between tumor size and CP%. The other side, the average tumor size in each group was 26.6 mm, 28.7 mm, and 37.8 mm in the Group A, B, and C, respectively. The average tumor size in Group C was significantly greater than those of Group A and B (P<0.01). The presence of gait disturbance in Group C was significantly higher than the other groups (P<0.01). The other side, abnormal ETT and OKP were seen in 32.5% and 31.9% of all patients, respectively. ETT and OKP results improved postoperatively in 67.4% and 68.9% of these patients.Conclusions: Abnormal ETT and OKP results showed positive correlations with the tumor size and presence of subjective symptoms. Further, dysfunction of cerebellum and brain stem owing to tumor compression was observed to recover in many cases after surgery. [ABSTRACT FROM AUTHOR]

We aimed to perform three-dimensional imaging of the underlying geothermal system to a depth of 2 km using magnetotellurics (MT) at around the Yugama crater, the Kusatsu–Shirane Volcano, Japan, which is known to have frequent phreatic eruptions. We deployed 91 MT sites focusing around the peak area of 2 km × 2 km with typical spacings of 200 m. The full tensor impedances and the magnetic transfer functions were inverted, using an unstructured tetrahedral finite element code to include the topographic effect. The final model showed (1) low-permeability bell-shaped clay cap (C1) as the near-surface conductor, (2) brine reservoir as a deep conductor (C3) at a depth of 1.5 km from the surface, and (3) a vertical conductor (C2) connecting the deep conductor to the clay cap which implies an established fluid path. The columnar high-seismicity distribution to the east of the C2 conductor implies that the flushed vapor and magmatic gas was released from the brine reservoir by breaking the silica cap at the brittle–ductile transition. The past magnetization/demagnetization sources and the inflation source of the 2014 unrest are located just below the clay cap, consistent with the clay capped geothermal model underlain by brine reservoir. The resistivity model showed the architecture of the magmatic–hydrothermal system, which can explain the episodic volcanic unrest. [ABSTRACT FROM AUTHOR]

Objective The skills of ear surgery are best developed by dissecting a temporal bone. However, only a limited number of trainees can be afforded this opportunity because of the scarcity of available bones. The aim of this study was to investigate the validity of a prototype temporal bone model for surgical training and education. Material and Methods A simulated 3D model of a human temporal bone was made using a selective laser sintering method. The powder layers were laser-fused based on detailed CT data and accumulated to create a 3D structure. Conventional surgical instruments were used to dissect the model under a microscope. Results The model was as hard as real bone and surface structures were accurately reproduced. The model could be shaved using a surgical drill, burr and suction irrigator in the same way as a real bone. The malleus and incus were reproduced. The semicircular canals and the oval and round window niches were identified. Cavity structures, such as the semicircular canal, vestibule, antrum and air cells, were filled with powder which had to be removed using a pick and suction irrigator during dissection. A magnified model was useful for educating medical students. Conclusion This prototype 3D model made using selective laser sintering serves as a good educational tool for middle ear surgery. [ABSTRACT FROM AUTHOR]

Introduction: Immune-related adverse events (irAEs) from nivolumab can affect any organ, but renal impairment is less common than effects on other organs. We encountered a case in which a renal irAE was difficult to diagnose due to mild renal dysfunction. Case Presentation: We report the case of a 65-year-old man with hypopharyngeal carcinoma treated with radiotherapy and cisplatin. Histopathological examination after reconstructive surgery showed extranodal invasion. Two months after completing treatment, computed tomography showed multiple lung metastases. We determined that the tumors were platinum-resistant and initiated treatment with nivolumab. Pyuria, worsening renal function, and elevation of C-reactive protein (CRP) to 16 mg/dL were observed 203 days after the first dose and nivolumab was discontinued. We considered the possibility of renal irAE but did not perform renal biopsy because creatinine was not highly elevated. We administered antibiotics for urinary tract infection, but CRP rose to 20 mg/dL and his general condition gradually worsened. Arthralgia in both knees and elbows appeared around the same time and gallium scintigraphy showed polyarticular accumulations. After diagnosing irAE arthritis, 20 mg of prednisolone was administered. Arthralgia and inflammatory responses improved, along with urinary findings and tubular markers. Retrospectively, pyuria, mild renal dysfunction, and elevated CRP were considered to reflect renal irAE. Conclusion: In some cases of mild renal dysfunction, as in the present case, biopsy may not be performed and the diagnosis may be missed. Renal irAEs should be kept in mind when abnormal urinalysis results and renal dysfunction are observed. [ABSTRACT FROM AUTHOR]

Aim Methods Results Conclusion This prospective observational study aimed to investigate the effects of ryokeijutsukanto on dizziness in patients with orthostatic dysregulation (OD) and explore its potential to address diverse symptoms resulting from autonomic dysfunction. This study also aimed to identify the factors contributing to the effectiveness of ryokeijutsukanto in managing OD.Patients diagnosed with OD were treated with ryokeijutsukanto between February 4, 2022 and April 1, 2024. Patients underwent various assessments and completed questionnaires, including the Vertigo Symptom Scale‐Short Form (VSS‐sf), Dizziness Handicap Inventory, Visual Analog Scale, and Gastrointestinal Symptom Rating Scale before and after treatment. The differences in these scores were analyzed based on age, sex, qi counterflow, and fluid disturbance.A total of eight patients were enrolled in the study; five cases had orthostatic hypotension and three had Postural Tachycardia Syndrome. Qi counterflow was observed in three cases and fluid disturbance was in six cases. Patients less than 40 years of age showed significantly higher improvement in the VSS‐sf scores than older patients, suggesting age‐based differences in treatment outcomes.This study did not find significant improvements in the various assessments used after ryokeijutsukanto treatment for OD. However, age‐based analysis indicated that the treatment may be more effective in younger patients. These results should be interpreted with caution, considering the limited sample size. Further research with larger cohorts is required to validate these findings. This study also acknowledges the need for larger multicenter studies to explore the potential benefits of ryokeijutsukanto in managing OD. [ABSTRACT FROM AUTHOR]

SUMMARY: The solution of the remote reference method, a frequently used technique in magnetotelluric (MT) data processing, can be viewed as a product of the two-input–multiple-output relationship between the local electromagnetic field and the reference field at a remote station. By applying a robust estimator to the two-input–multiple-output system, one can suppress the influence of outliers in the local magnetic field as well as those in the local electric field based on regression residuals. Therefore, this study develops a new robust remote reference estimator with the aid of robust multivariate linear regression. By applying the robust multivariate regression S-estimator to the multiple-output system, the present work derives a set of equations for robust estimates of the transfer function, noise variances, and the scale of the Mahalanobis distance simultaneously. The noise variances are necessary for the multivariate analysis to normalize the residuals of dependent variables. The Mahalanobis distance, a distance measure for multivariate data, is a commonly used indicator of outliers in multivariate statistics. By updating those robust estimates iteratively, the new robust remote reference estimator seeks the transfer function that minimizes the robust scale estimate of the Mahalanobis distance. The developed estimator can avoid bias in the MT transfer function even if there are significant noises in the reference magnetic field and handle outlying data more robustly than previously proposed robust remote reference estimators. The authors applied the developed method to a synthetic data set and real-world data. The test results demonstrate that the developed method downweights outliers in the local electric and magnetic fields and gives an unbiased transfer function. [ABSTRACT FROM AUTHOR]

We estimate the mass and energy budgets for the 2018 phreatic eruption of Mt. Motoshirane on Kusatsu–Shirane volcano, Japan, based on data obtained from a network of eight tiltmeters and weather radar echoes. The tilt records can be explained by a subvertical crack model. Small craters that were formed by previous eruptions are aligned WNW–ESE, which is consistent with the strike of the crack modeled in this study. The direction of maximum compressive stress in this region is horizontal and oriented WNW–ESE, allowing fluid to intrude from depth through a crack with this orientation. Based on the crack model, hypocenter distribution, and MT resistivity structure, we infer that fluid from a hydrothermal reservoir at a depth of 2 km below Kusatsu–Shirane volcano has repeatedly ascended through a pre-existing subvertical crack. The inflation and deflation volumes during the 2018 eruption are estimated to have been 5.1 × 105 and 3.6 × 105 m3, respectively, meaning that 1.5 × 105 m3 of expanded volume formed underground. The total heat associated with the expanded volume is estimated to have been ≥ 1014 J, similar to or exceeding the annual heat released from Yugama Crater Lake of Mt. Shirane and that from the largest eruption during the past 130 year. Although the ejecta mass of the 2018 phreatic eruption was small, the eruption at Mt. Motoshirane was not negligible in terms of the energy budget of Kusatsu–Shirane volcano. A water mass of 0.1–2.0 × 107 kg was discharged as a volcanic cloud, based on weather radar echoes, which is smaller than the mass associated with the deflation. We suggest that underground water acted as a buffer against the sudden intrusion of hydrothermal fluids, absorbing some of the fluid that ascended through the crack. [ABSTRACT FROM AUTHOR]

We estimate the mass and energy budgets for the 2018 phreatic eruption of Mt. Motoshirane on Kusatsu–Shirane volcano, Japan, based on data obtained from a network of eight tiltmeters and weather radar echoes. The tilt records can be explained by a subvertical crack model. Small craters that were formed by previous eruptions are aligned WNW–ESE, which is consistent with the strike of the crack modeled in this study. The direction of maximum compressive stress in this region is horizontal and oriented WNW–ESE, allowing fluid to intrude from depth through a crack with this orientation. Based on the crack model, hypocenter distribution, and MT resistivity structure, we infer that fluid from a hydrothermal reservoir at a depth of 2 km below Kusatsu–Shirane volcano has repeatedly ascended through a pre-existing subvertical crack. The inflation and deflation volumes during the 2018 eruption are estimated to have been 5.1 × 105 and 3.6 × 105 m3, respectively, meaning that 1.5 × 105 m3 of expanded volume formed underground. The total heat associated with the expanded volume is estimated to have been ≥ 1014 J, similar to or exceeding the annual heat released from Yugama Crater Lake of Mt. Shirane and that from the largest eruption during the past 130 year. Although the ejecta mass of the 2018 phreatic eruption was small, the eruption at Mt. Motoshirane was not negligible in terms of the energy budget of Kusatsu–Shirane volcano. A water mass of 0.1–2.0 × 107 kg was discharged as a volcanic cloud, based on weather radar echoes, which is smaller than the mass associated with the deflation. We suggest that underground water acted as a buffer against the sudden intrusion of hydrothermal fluids, absorbing some of the fluid that ascended through the crack. [ABSTRACT FROM AUTHOR]

Inter-plate coupling on the Hikurangi subduction margin along the east coast of New Zealand's North Island changes from weakly coupled in the north to locked in the south. 3-D inverse modeling of magnetotelluric (MT) data across the coupling transition shows that the electrical resistivity structure is correlated with the areal strain rate, which provides a measure of plate coupling. The correlation between strain rate and resistivity is seen parallel to the strike and dip directions of the subduction. In the region where the strain is extensional, the upper plate is more conductive than in the south where contraction is occurring, and the plates are locked. The increased mid-crustal resistivity in the south can be interpreted to be a consequence of reduced fluid interconnectivity due to contraction or reduced fluid content due to decreased upward transport from sources beneath the subduction interface. The increased mid-crustal conductivity in the extensional area is interpreted to be a consequence of fluid released by subducted sediment that are also the cause of the extension. Seismicity in the upper 5 km of the subducting plate shows similar changes, with a greater concentration of near-interface seismicity beneath the conductive (extensional) region. We interpret the concentration of seismicity below the subduction interface in the extensional region to show fluid sourced from dehydration reactions within the subducting plate or from the de-watering of subducted sediments rising into the upper plate and decreasing the resistivity of the middle crust. Decreased near-interface seismicity beneath the contractional region can be interpreted to be a consequence of decreased upper plate permeability preventing upward fluid escape or reduced lower plate fluid availability. • The electrical resistivity of the upper-plate correlates with the areal strain-rate. • Where the plate is conductive, geodetic data suggest a weakly coupled interface. • The reduced resistivity is caused by fluid released from the underlying plate. • The higher resistivity in the locked area reflects decreased upward fluid-transport. [ABSTRACT FROM AUTHOR]

We estimate the mass and energy budgets for the 2018 phreatic eruption of Mt. Motoshirane on Kusatsu–Shirane volcano, Japan, based on data obtained from a network of eight tiltmeters and weather radar echoes. The tilt records can be explained by a subvertical crack model. Small craters that were formed by previous eruptions are aligned WNW–ESE, which is consistent with the strike of the crack modeled in this study. The direction of maximum compressive stress in this region is horizontal and oriented WNW–ESE, allowing fluid to intrude from depth through a crack with this orientation. Based on the crack model, hypocenter distribution, and MT resistivity structure, we infer that fluid from a hydrothermal reservoir at a depth of 2 km below Kusatsu–Shirane volcano has repeatedly ascended through a pre-existing subvertical crack. The inflation and deflation volumes during the 2018 eruption are estimated to have been 5.1 × 105 and 3.6 × 105 m3, respectively, meaning that 1.5 × 105 m3 of expanded volume formed underground. The total heat associated with the expanded volume is estimated to have been ≥ 1014 J, similar to or exceeding the annual heat released from Yugama Crater Lake of Mt. Shirane and that from the largest eruption during the past 130 year. Although the ejecta mass of the 2018 phreatic eruption was small, the eruption at Mt. Motoshirane was not negligible in terms of the energy budget of Kusatsu–Shirane volcano. A water mass of 0.1–2.0 × 107 kg was discharged as a volcanic cloud, based on weather radar echoes, which is smaller than the mass associated with the deflation. We suggest that underground water acted as a buffer against the sudden intrusion of hydrothermal fluids, absorbing some of the fluid that ascended through the crack. [ABSTRACT FROM AUTHOR]

• Holistic overview of the Okataina Volcanic Centre (OVC) of New Zealand. • Crustal imaging and melt distribution. • Tectonic-volcanic interactions. • Heat and hydrothermal activity. • Modelling the hydrosphere. [ABSTRACT FROM AUTHOR]

Intraplate earthquakes occur more frequently in the Japanese islands than in other regions. Large intraplate earthquakes in the island arc preferentially occur in strain concentration zones detected by geological and geodetic studies. Crustal heterogeneity plays a crucial role in generating large intraplate earthquakes and strain concentrations. Thus, we elucidated the crustal heterogeneities beneath a strain concentration area on the back‐arc side of the northeastern Japan Arc based on electrical resistivity, which is sensitive to weak zones in the crust. By deploying wideband magnetotelluric surveys, we revealed the three‐dimensional electrical resistivity structure in the crust, suggesting the coexistence of two different types of strain‐concentration mechanisms in the strain‐concentration area. The shallow conductive layers and lower‐crustal conductors appear to act as low‐elastic‐modulus and low‐viscosity areas, respectively, and are responsible for the strain concentration. We found shallow and lower‐crustal conductors in the strain concentration zone revealed by geological studies. Those conductive areas are considered to act as mechanically weak zones and cause stress loading on the brittle pars of pre‐existing faults, resulting in large intraplate earthquakes. The resultant earthquakes presumably contribute to strain accumulation on a geological timescale. In addition, a spatial correlation between the epicenters of large intraplate earthquakes and edges of lower‐crustal conductors implies the contribution of the fluids in the lower crust to the generation of large earthquakes. We also identified vertical conductors ranging from the lower crust to Quaternary volcanoes, which may indicate trans‐crustal magmatic systems under these volcanoes. Plain Language Summary: Intraplate earthquakes occur more frequently in the Japanese islands than in other regions worldwide. Large intraplate earthquakes in this region preferentially occur in high‐deformation zones, as detected by geological studies and global positioning system (GPS) measurements. Heterogeneous structure in the crust plays a crucial role in the generation of large intraplate earthquakes and high crustal deformations. Thus, we revealed the three‐dimensional crustal electrical resistivity structure beneath a strain‐concentration area in the northeastern Japan. The resistivity structure suggests the coexistence of two different mechanisms of high deformation. Shallow conductive layers and lower‐crustal conductors appear to act as low‐stiffness and low‐viscosity areas, respectively, leading to high crustal deformation. We found shallow and deep conductors in the high‐deformation zones revealed by geological studies. As both can act as weak zones, those conductors presumably play a key role in loading on faults, resulting in intraplate earthquakes. Because the epicenters of large intraplate earthquakes are positioned near the edges of lower‐crustal conductors, the fluids in those deep conductors possibly contribute to the generation of large earthquakes. We also revealed vertical conductors ranging from the deep crust to Quaternary volcanoes, which may indicate magma‐rich areas under these volcanoes. Key Points: The electrical resistivity structure suggests the coexistence of two strain‐concentration mechanisms in the strain‐concentration areaThe shallow conductive layers and lower‐crustal conductors act as low‐elastic‐modulus and low‐viscosity areas, respectivelyWeak zones in the crust, imaged as conductors, presumably cause stress loading on faults and contribute to large intraplate earthquakes [ABSTRACT FROM AUTHOR]

On 29 June 2015, a small phreatic eruption occurred at Hakone volcano, Central Japan, forming several vents in the Owakudani geothermal area on the northern slope of the central cones. Intense earthquake swarm activity and geodetic signals corresponding to the 2015 eruption were also observed within the Hakone caldera. To complement these observations and to characterise the shallow resistivity structure of Hakone caldera, we carried out a three-dimensional inversion of magnetotelluric measurement data acquired at 64 sites across the region. We utilised an unstructured tetrahedral mesh for the inversion code of the edge-based finite element method to account for the steep topography of the region during the inversion process. The main features of the best-fit three-dimensional model are a bell-shaped conductor, the bottom of which shows good agreement with the upper limit of seismicity, beneath the central cones and the Owakudani geothermal area, and several buried bowl-shaped conductive zones beneath the Gora and Kojiri areas. We infer that the main bell-shaped conductor represents a hydrothermally altered zone that acts as a cap or seal to resist the upwelling of volcanic fluids. Enhanced volcanic activity may cause volcanic fluids to pass through the resistive body surrounded by the altered zone and thus promote brittle failure within the resistive body. The overlapping locations of the bowl-shaped conductors, the buried caldera structures and the presence of sodium-chloride-rich hot springs indicate that the conductors represent porous media saturated by high-salinity hot spring waters. The linear clusters of earthquake swarms beneath the Kojiri area may indicate several weak zones that formed due to these structural contrasts. [ABSTRACT FROM AUTHOR]

Background: Bow Hunter's Syndrome (BHS) is known as one of cervical diseases which causes vertigo, but the details of its vertigo, especially nystagmus and eye movement, are still incompletely understood. This time, we reported the first case of BHS with a nystagmus chart with video record of transitional nystagmus.Case Presentation: The patient, a 47-year-old female, complained of vertigo caused by head rotation. When she turned her head leftward, leftward nystagmus appeared, and this was followed by dullness of the right arm. After her head was returned to the central position, downbeat nystagmus appeared, which changed to rightward nystagmus. She was diagnosed with BHS by her symptoms and images. We recorded a nystagmus video and nystagmus chart of this transitional nystagmus including downbeat nystagmus. Her vertigo was cured by the modification of a prescription for her past medical history: hypertension.Conclusion: The vertigo of BHS accompanies nystagmus. In this present case, the transitional nystagmus was observed, and it occurred toward the healthy side. Then the nystagmus direction was changed to the affected side via downbeat nystagmus. This is the first report with both a nystagmus chart with video of BHS. Nowadays, various kinds of vertigo induced by neck movement are known. BHS is a rare disease among vertigo diseases, but we should consider it as a different diagnosis of vertigo patients. A precise interview and proper examination are required to make the final diagnosis. [ABSTRACT FROM AUTHOR]

Triggering intrusions of phreatic eruptions are often observed as seismic and ground deformation signals on a time scale of minutes. The current understanding of hydrothermal intrusions still needs improvement to obtain insight into the eruption scale from the observables. We examine local geophysical data from the precursory hydrothermal intrusion of the 2018 phreatic eruption of Kusatsu‐Shirane volcano. To achieve an integrated intrusion model, we divide analyzing time window into the onset, middle, and climax. Focusing on the transient response of tilt data for the sudden pressurization, we estimate a vertical tensile opening (1.7 × 103 m3/s in 40 s) at 1.1 km depth for the intrusion onset. Pressurization can represent the start of vapourization. Very long period (VLP, 0.033–0.1 Hz) seismic signals are adopted to constrain the middle and climax phases. We obtained two sequential semi‐horizontal tensile crack oscillation sources with peak volume changes of 3.6 × 104–1.9 × 105 m3 at 0.3–0.6 km depths. The second VLP source acted as a final trigger of the eruption to cause depressurization in the shallow portion of the intruded region, which is constrained as having reached 0.1 km depth by surface deformation. Simultaneously, we find another depressurization originated from depth in the climax due to a decrease in the hydrothermal intrusion rate. Through comparison with the 2014 Ontake phreatic eruption, the total inflation volume may correlate with eruption scales. Intruded hydrothermal fluid and local structure characteristics also may have to be considered to evaluate the eruptions scales from inferred signal source intensity. Plain Language Summary: Phreatic eruptions, emitting non‐fresh magma fragments, are driven by underground water and gas mixtures intruding into the subsurface. Local geophysical observations often detect intrusions as seismic and ground deformation signals. Those observation data potentially provide insight into eruption and hazard scale evaluations. However, such an interpretation is still challenging for the current understanding. This paper examines seismic and ground deformation data associated with the precursory intrusion of a phreatic eruption at Kusatsu‐Shirane volcano in Japan, revealing a detailed hydrothermal intrusion process. Using ground deformation data, we have found that an aqueous intrusion started at 1.1 km depth. This starting process may represent the vapourization onset of underground water and gas mixtures. By analyzing seismic signals having a longer dominant period (>10 s), we revealed the intrusion path from the starting region to beneath the 2018 eruption vent and the final triggering for the eruption. Through comparisons with other phreatic eruptions, we find that the total deformation volume may correlate with the eruption intensity scales such as the mass emitted volcanic ash and the maximum eruption cloud height. However, there is still room for considering hydrothermal fluid characteristics and local structures to evaluate the eruption scale properly from observed data. Key Points: A sudden hydrothermal intrusion onset is constrained by adopting transient tiltmeter responsesVery long period band seismic signals reflect the hydrothermal intrusion behaviors during the middle and climax phasesTilt and seismic records show precursory depressurization in shallow depth as the final eruption trigger [ABSTRACT FROM AUTHOR]

Along the Hikurangi subduction margin, on the east coast of New Zealand's North Island, the interplate coupling changes from locked in the south to weakly coupled in the north. New magnetotelluric (MT) data from 151 locations linking previous MT surveys into a single contiguous data set that encompasses the weakly coupled part of the margin are analysed. By inverting the combined data we have constructed a 3-D image of the electrical resistivity of the subduction interface shear zone along a 300-km-long segment of the margin. Our results show that the electrical resistivity of the subduction interface shear zone is heterogenous; the degree of heterogeneity decreasing from north to south. The resistivity heterogeneities correlate well with the distribution of near-plate interface seismicity, Vp / Vs values and the pattern of areal strain rate derived from GPS data. These correlations are consistent with variations in the fluid content of the subduction interface shear zone. In the northern part of this segment, conductive areas adjacent to the interface are interpreted to be fluid rich areas where seismicity is sparse, Vp / Vs ratios are high and the areal strain rate is extensional. In contrast, where the areal strain rate is compressional the plate interface is more resistive, and seismicity is more abundant consistent with greater interplate friction. In the south, the resistivity of the plate interface is more homogenous, and the overlying plate is more resistive at shallower levels than in the north. Our results support the hypothesis that the fluid and/or hydrated clay content of the subduction interface shear zone are an important control on interplate coupling. [ABSTRACT FROM AUTHOR]

The finite element method using an unstructured tetrahedral mesh is one of the most effective methods for the 3-D modelling of marine magnetotelluric data that are strongly affected by bathymetry, because it enables us to incorporate both small-scale and regional-scale bathymetry into a computational mesh with a practical number of elements. The authors applied a 3-D inversion scheme using mesh of this type to marine magnetotelluric problems for the first time and verified its applicability. Forward calculations for two bathymetry models demonstrated that the results obtained with an unstructured tetrahedral mesh are close to the reference solutions. To evaluate the forward calculation results, we developed a general TM-mode analytical formulation for a 2-D sinusoidal topography. Moreover, synthetic inversion test results confirmed that a 3-D inversion scheme with an unstructured tetrahedral mesh enables us to recover subseafloor resistivity structure properly even for a model including a land–sea boundary as well as seafloor undulations. The verified inversion scheme was subsequently applied to a set of marine magnetotelluric data observed around the Iheya North Knoll, the middle Okinawa Trough. 3-D modelling using a mesh with precise bathymetry demonstrated that the data observed around the Iheya North Knoll are strongly affected by bathymetry, especially by the sea-depth differences between the depression of the trough and the shallow East China Sea. The estimated resistivity structure under the knoll is characterized by a conductive surface layer underlain by a resistive layer. The conductive layer implies permeable pelagic/hemipelagic sediments, which are consistent with a previous seismological study. Furthermore, the conductive layer has a resistive part immediately below the knoll, which is regarded as the consolidated magma intrusion that formed the knoll. Furthermore, at a depth of 10 km, we found that the resistor underneath the knoll extends to the southeast, implying that subseafloor resistivity under the Volcanic Arc Migration Phenomenon area is more resistive than the surroundings due to the presence of consolidated magma. [ABSTRACT FROM AUTHOR]

The dynamics of magma reservoirs (the main repositories for eruptible magma) play a fundamental role in the style and behaviour of volcanic systems. A key first step in understanding these systems is to identify their location and size accurately. We present results from a broadband magnetotelluric study of the Tongariro Volcanic system and discuss how the results fit within current petrological models. The Tongariro Volcanic system is a composite andesitic cone complex, located at the southern end of the Taupo Volcanic Zone in the central North Island of New Zealand. We use data from 136 broadband magnetotelluric soundings within a 25 × 35 km area covering the volcanic system to construct a 3D image of the magmatic system of the Tongariro Volcanic Complex including Mount Ngauruhoe. The structure of the Tongariro magmatic system has been determined from 3D forward and inverse modelling of the magnetotelluric data and allowed for an estimation of the melt fraction present within the system. 3D inverse modelling of the magnetotelluric data shows: a well-developed shallow low resistivity zone outlining the geothermal system; a zone of even lower resistivity representing a shallow crustal magma accumulation zone located at a depth of ∼4–12 km offset to the east of the Tongariro vent system; and a zone with a slightly higher resistivity connecting these two components of the magmatic system providing the path for magmatic fluids from the deeper source region to reach the surface during eruptive events. [ABSTRACT FROM AUTHOR]

Nivolumab administration to patients with organ transplantation history requires careful management. Herein, we report the case of a living-donor liver-transplant recipient, a 52-year-old man, with recurrent and metastatic hypopharyngeal cancer treated with nivolumab. He was diagnosed with T2N2bM0 stage IVA hypopharyngeal squamous cell carcinoma. While using oral immunosuppressants (cyclosporine and mycophenolate mofetil), the patient underwent right neck dissection followed by radiotherapy as an initial treatment. Three months after radiotherapy, positron emission tomography scans revealed multiple bone metastases. We administered two courses of the EXTREME regimen, comprising cisplatin, 5-fluorouracil, and cetuximab, as the first-line treatment for distal metastasis, but the patient presented with progressive disease. The patient was administered nivolumab as the second-line treatment. The programmed death-ligand 1 (PD-L1) expression level in a biopsy specimen of the primary hypopharyngeal tumor and resected specimen of the cervical lymph node metastasis was 40% and 10%, respectively. PD-L1 expression was not detected in hepatocytes of the liver biopsy sample obtained before nivolumab introduction. The patient received four courses of nivolumab 240 mg. Although liver dysfunction was alleviated by adjusting the dose of the hepatoprotective agent and cyclosporine, the progressive disease status persisted after completing nivolumab courses. The patient died of hypopharyngeal cancer progression. [ABSTRACT FROM AUTHOR]