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Oxygen-containing carbon materials such as graphene oxide have been extensively studied because of their high dispersibility. However, the oxygen-containing functional groups in most carbon materials are not controlled. Uncontrollability of the synthesis is also one of factors that prevent industrialization. Carbon materials derived from phloroglucinol (PG), which show high solubility/dispersibility and controllability of functional groups, have been developed recently by our group. The high performance of carbonized PG originates from the thermally stable backbone structure of the benzene ring with hydroxy groups of PG. However, the degree of carbonization was low. In this study, five heteropoly acids (HPAs), which are thermally stable homogeneous strong acid catalysts, were used to promote carbonization of PG without losing the controllability of functional groups and the dispersibility. HPAs promoted etherification of hydroxy groups followed by C=C coupling reactions (furan cyclization) at 523 K. Furthermore, it was confirmed that particularly furan structures, which contribute to solubility/dispersibility in solvents, and thermal stability in air, could be maintained at 673 K as suggested by spectroscopies and thermogravimetric-differential thermal analysis. Among five HPAs, phosphotungstic acid worked as the excellent catalyst to promote carbonization of PG containing furan structures, exhibiting high solubility/dispersibility and high thermal stability in air.

Pentagons in carbon materials have attracted attentions because of the potential high chemical reactivity, band gap control, and electrochemical activity. However, it is challenging to prepare a carbon film with high pentagon density because of the curvature and the high reactivity caused by the presence of pentagons, and it is also challenging to estimate the percentage of pentagons in carbon materials because of the limitation of current analytical techniques. In this work, the percentage of pentagons in carbon materials was experimentally estimated for the first time using experimental and calculated C1s X-ray photoelectron spectroscopy and elemental analysis. Carbon films with 7% of pentagons (40% of pentagons compared to the raw material) with electrical resistivity of 1.1 × 104 Ω meter were prepared by heat treatment of corannulene at 873 K. On the other hand, fluoranthene and fullerene remained as non-film solid and powder without forming films at 873 K. Experimental and calculated Raman and IR spectra revealed the peaks of different types of pentagons. Decrement of pentagons in corannulene and fluoranthene heated at high temperatures can be explained mainly by the scission of C=C bond in pentagons, as suggested by the results of reactive molecular dynamics simulation (ReaxFF).

Background: The prevalence of unruptured intracranial aneurysms is increasing in elderly population in Japan. Octogenarians (80–89 years) are more prone to complications due to increased age, comorbidities, increased risk of vasospasm, and treatment risks. Aim: The aim is to study the surgical outcome of unruptured intracranial saccular aneurysms in elderly patients aged between 80 and 89 years. Patients and Methods: A retrospective study was conducted involving all the cases of unruptured intracranial saccular aneurysms operated surgically in elderly patients aged between 80 and 89 years. All the cases operated between January 2017 and October 2019 were included in the study. The preoperative neurological status was assessed using the Glasgow Coma Scale (GCS). The comorbidities and risk factors involved were assessed. Postoperative neurological status was assessed by (1) postoperative GCS score and by the (2) presence or absence of the motor weakness of limbs. Results: Thirty-three aneurysms were operated in 27 patients. Two patients were operated two times at separate occasions for different aneurysms during the study period and hence making a total of 29 surgeries. The age range was 80–88 years, with a mean of 82.4 years ± 2.64 standard deviation (SD). There were 7 (24.1%) males and 22 (75.86%) females. All the patients had a preoperative GCS score of 15/15 without focal neurological deficit. The mean size (mm) of the aneurysms was 6.57 ± 4.04 SD. There were 31 (93.94%) aneurysms in the anterior circulation and 2 (6.06%) aneurysms in the posterior circulation. The comorbidities and risk factors were analyzed and found to be not influencing the outcome of the patients. Clipping was done in 32 aneurysms. One case of posterior inferior cerebellar artery (PICA) aneurysm underwent occipital artery to PICA bypass surgery. The postoperative complications include chronic subdural hematoma (CSDH) in 7 (24.13%) patients, extradural hematoma in 1 (3.4%), meningitis in 1 (3.4%), and lower cranial nerve palsy in 1 (3.4%) patient. All the patients were discharged with GCS score 15/15 without motor weakness of the limbs. The mean duration of stay was 16.62 days ± 9.98 SD. Conclusion: Surgery for unruptured saccular aneurysms in octogenarians has got a good result in the tertiary care facility. Advanced age alone should not be considered for preferring coiling over clipping. Octogenarians are more prone to developing postoperative CSDH.

Introduction: Posterior circulation aneurysm constitutes 15%–20% of all intracerebral aneurysms. With the advancement of endovascular techniques, the microsurgery for posterior circulation aneurysms has been pushed back a little. Even the International Subarachnoid Aneurysmal Trial gave support to the concepts of endovascular procedures, but microsurgical modality should not be discouraged. We present our institutional experience of microsurgical techniques on posterior circulation aneurysms. Materials and Methods: We performed a retrospective analysis of 37 patients of posterior circulation aneurysm from 2015 to 2019, referred to Bantane Hospital, Japan. We included all posterior circulation aneurysms such as basilar tip, basilar trunk, and vertebral artery-posterior inferior cerebellar artery (VA-PICA) aneurysms, admitted and treated with clipping or bypass and trapping. We assessed the outcome as measured by modified Rankin Score (mRS), complications, and mortality. Results: Out of 37 patients, 10 cases were a basilar tip, one case was the basilar trunk, and 26 cases were VA-PICA aneurysm. Intraoperatively, neuromonitoring, indocyanine green dye, dual-image videoangiography (DIVA), and neuro endoscope were used. Two patients of basilar tip aneurysm developed third cranial nerve paresis and six patients of VA-PICA aneurysm developed lower cranial nerve paresis which resolved spontaneously. All the patients were discharged with mRS of 0 or 1. No mortality was recorded in our study. Conclusion: Microsurgical clipping of posterior circulation aneurysm is safe in unruptured aneurysm with a very low risk of mortality and morbidity under experienced hands. All postoperative complications in our study were transient and resolved with time with no residual deficits. Preoperative simulation, intraoperative neuromonitoring, DIVA, and neuro endoscope help achieve complete obliteration of aneurysmal sac and avoid complications.

Background: Extracranial-intracranial (EC-IC) arterial bypass has been used in the treatment of various cerebrovascular ischemic disease due to atherosclerosis or Moyamoya disease, skull base tumors encasing large IC artery or complex IC aneurysms. Aim: The aim is to analyze surgical technique (EC-IC bypass) and its outcome with intraoperative use of dual image video angiography (DIVA) and Doppler ultrasound. Materials and Methods: We studied in this article a series of 23 patients operated in Banbuntane Hotokukai Hospital, Fujita Health University, for which a superficial temporal artery-middle cerebral artery anastomosis was done for steno-occlusive disease, giant IC aneurysm or Moyamoya disease. The study was conducted between 2018 and 2020. We used dual-image video angiography (DIVA) and Doppler ultrasound to assess the luminal patency of anastomosis during the procedure. Results: In this study, three patients presented with Moyamoya disease, 4 had aneurysm, whereas 16 patients presented with the vascular steno-occlusive disease. The patients were divided into three categories (steno-occlusive disease, Moyamoya, and flow replacement for giant aneurysm). Dual image video angiography, along with intraoperative Doppler, helped us in the assessment of luminal patency of the anastomosis. Conclusion: Hemodynamic recovery after cerebrovascular bypass brings about a better outcome in ischemic stroke. The result of surgery improves with proper selection of patients with hemodynamic impairment (in Stage 2). With various modalities such as intraoperative Doppler, DIVA (Dual-image Video Angiography) and improved surgical techniques may aid in the reduction of complications and improve clinical outcome.

Cortical blindness (CB) due to contrast-induced encephalopathy is a rare complication in endovascular procedure. Although exact mechanism is not known, disruption of blood–brain barrier (BBB) by contrast agent is supposed to be caused. We report two cases of contrast-induced encephalopathies after coil embolization of unruptured aneurysm. A 68-year-old woman with unruptured basilar artery aneurysm was treated with endovascular stent-assisted coil embolization. The procedure was successfully accomplished within 172 min using about 160 ml of contrast medium (iopamidol). However, she manifested with CB 3 h after the procedure and seizure on the next day. Immediate computed tomography revealed the cortical enhancement in both occipital lobes. Diffusion-weighted imaging–magnetic resonance imaging and fluid-attenuated inversion recovery sequence 1 day after the procedure revealed edema in both occipital lobes with no findings of ischemia or hyperperfusion. Electroencephalography showed sharp and slow waves in both occipital lobes. She required endotracheal intubation on day 2 to maintain airways and breathing. Her sensorium improved 4 days after the procedure with administration of steroid and anticonvulsant. She was extubated on day 4 after the procedure. She was discharged with persisting CB as a sequel.

Sandy trench-fill sediments at accretionary margins are commonly scraped off at the frontal wedge and rarely subducted to the depth of high-pressure (HP) metamorphism. However, some ancient exhumed accretionary complexes are associated with high-pressure–low-temperature (HP-LT) metamorphic rocks, such as psammitic schists, which are derived from sandy trench-fill sediments. This study used sandbox analogue experiments to investigate the role of seafloor topography in the transport of trench-fill sediments to depth during subduction. We conducted two different types of experiments, with or without a rigid topographic high (representing a seamount). We used an undeformable backstop that was unfixed to the side wall of the apparatus to allow a seamount to be subducted beneath the overriding plate. In experiments without a seamount, progressive thickening of the accretionary wedge pushed the backstop down, leading to a stepping down of the décollement, narrowing of the subduction channel, and underplating of the wedge with subducting sediment. In contrast, in experiments with a topographic high, the subduction of the topographic high raised the backstop, leading to a stepping up of the décollement and widening of the subduction channel. These results suggest that the subduction of stiff topographic relief beneath an inflexible overriding plate might enable trench-fill sediments to be deeply subducted and to become the protoliths of HP-LT metamorphic rocks.

Introduction: Hearing loss following microvascular decompression (MVD) for hemifacial spasm is one of the most dreaded complications. Several factors such as stretching of VIII cranial nerve, vasospasm of labyrinthine artery, and acoustic trauma due to drill noise may be considered in its causation. We evaluated the incidence and severity of hearing loss following MVD in hemifacial spasm and the factors which might be responsible for this complication. Methods: A retrospective analysis of 30 patients operated for hemifacial spasm between January 1, 2014, and December 31, 2018, with at least 3 months of follow-up were included in the study. Retromastoid craniotomy was made, and Teflon was placed between involved vessel and VII nerve. Results: Freedom from hemifacial spasm was noted in 27 of 30 patients. Moderate spasm persisted in one patient, which was controlled with medications. The recurrence was noted in 3 patients at 6 months follow-up. Postoperatively, hearing loss was found in one female patient. The offending vessel was both anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA) loop, which was transpositioned during surgery, and the patient was spasm free postoperatively. Conclusion: The incidence of hearing loss following MVD can be minimized using proper surgical techniques and various intraoperative adjuncts such as brainstem auditory evoked responses monitoring, use of endoscope, and indocyanine green or dual-image video angiography.

Oxygen-containing carbon materials such as graphene oxide have been studied intensively for a decade because of the high oxygen content, which is beneficial to disperse carbon materials in solutions and to support either metals or metal oxides on carbon materials. However, various oxygen-containing functional groups exist on carbon materials and controlling the structures is almost impossible. In this work, phloroglucinol (PG), which has a symmetrical structure with three hydroxyl groups relative to six aromatic carbon atoms, was found to be the best precursor among PG, cyanuric acid, trimesic acid, and melamine because of the high yield (63 wt%) at 573 K even in an open system which is essential for mass production. The materials synthesized from PG also showed the high dispersibility and/or solubility in solvents (N-methyl-2-pyrrolidone and N,N-dimethylformamide) and the low temperature to form carbon materials (573 K), which can be explained from (002) and (10) in X-ray diffraction pattern. X-ray photoelectron spectroscopy, Fourier transform infrared spectrometer, carbon-13 nuclear magnetic resonance with the aid of calculation of both spectra and carbonization mechanisms revealed that the high solubility of carbonized PG originates from the presence of ether and cyclic ether, which were formed from dehydration of hydroxy groups, and also some remained hydroxyl groups in carbonized PG. Oxygen-containing groups in carbonized PG were effective as an antioxidant. In addition, the coating of carbonized PG on silica nanoparticles imparted conductivity and lubricity to silica nanoparticles.

The Chikyu Shallow Core Program (SCORE) has been started to provide more opportunities for the scientific ocean drilling of shallow boreholes (up to 100 m) during a short-term expedition. The proposal flow is a simplified version of that of the International Ocean Discovery Program (IODP). Although there are several limitations for a SCORE project, the opportunity to retrieve 100 m of continuous core samples will be of great interest for the scientific ocean drilling community in multiple disciplines. The first expedition of the SCORE program was implemented off Cape Erimo, Hokkaido, northern Japan. The target of the drilling was to investigate the impact of submarine mass transport on the subseafloor sedimentary biosphere. In the preliminary observation of the core samples, including X-ray computed tomography (CT) scan image analysis, chaotic and inclined beds were found and interpreted as mass transport deposit (MTD) units.

Determination of the number of bromo groups and brominated positions of edges on carbon materials is essential for selective functionalization because the brominated positions influence their electronic structures. However, the determination is challenging because the analysis of introduced bromo groups on carbon materials is conventionally limited to quantitative analysis by X-ray photoelectron spectroscopy. In this work, infrared spectra (IR) of brominated aromatic compounds were analyzed experimentally and theoretically using reference aromatic compounds to verify that the calculated peak positions can be used to estimate the experimental peak positions of brominated aromatic compounds. IR spectra of brominated graphene nanoribbons (GNRs) with zigzag, armchair, and other edges were simulated as one of the carbon materials with clear edge structures. Their characteristic peak positions and tendencies of shifts were explained from the point of view of Mulliken charge, C–H and C=C length, and orbital hybridization. As the number of Br on GNRs increased, the peak positions basically shifted further, indicating that the density of Br and introduced positions of Br can be estimated from IR spectra. The detailed assignments obtained in this work will lead to selective functionalization of carbon materials.

Ependymoma is a rare tumor central nervous system that arises from the ependymal lining of the ventricles or the central canal of the spinal cord. They are of neuroectodermal in origin and constitute about 30%–86% of tumors arising in the spinal cord. The occurrence of these tumors in the cervicomedullary region is very rare. Sudden symptomatic neurologic presentations due to hemorrhage in cervicomedullary ependymoma is very rare and so far have never been reported. Mostly presenting as neurologic deficits involving limbs, these tumors pose a technical challenge in their removal. We present a patient who presented with sudden-onset dysesthesia of the upper and lower limbs. On imaging, he was found to have a cystic medullary tumor extending to the cervical region with hemorrhage. We discuss the epidemiology, surgical challenges, and outcome along with review of literature of these rare tumors located in this precarious location.

Radiation therapy is one of the major treatment modalities for patients with cancers. However, ionizing radiation (IR) damages not only cancer cells but also the surrounding vascular endothelial cells (ECs). Hippo pathway effector genes Yap1 and Taz are the two transcriptional coactivators that have crucial roles in tissue homeostasis and vascular integrity in various organs. However, their function in adult ECs at the steady state and after IR is poorly understood. Here, we report sex- and context-dependent roles of endothelial YAP1/TAZ in maintaining vascular integrity and organismal survival. EC-specific Yap1/Taz deletion compromised systemic vascular integrity, resulting in lethal circulation failure preferentially in male mice. Furthermore, EC-specific Yap1/Taz deletion induced acute lethality upon sublethal IR that was closely associated with exacerbated systemic vascular dysfunction and circulation failure. Consistent with these findings, RNA-seq analysis revealed downregulation of tight junction genes in Yap1/Taz-deleted ECs. Collectively, our findings highlight the importance of endothelial YAP1/TAZ for maintaining adult vascular function, which may provide clinical implications for preventing organ injury after radiation therapy.

Dynamically scaled experiments allow the direct comparison of geometrical, kinematical and mechanical processes between model and nature. The geometrical scaling factor defines the model resolution, which depends mainly on the density and cohesive strength ratios of model material and natural rocks. Granular materials such as quartz sands are ideal for the simulation of upper crustal deformation processes as a result of similar nonlinear deformation behaviour of granular flow and brittle rock deformation. We compared the geometrical scaling factor of common analogue materials applied in tectonic models and identified a gap in model resolution corresponding to the outcrop and structural scale (1–100 m).In this study, we present a new granular rock-analogue material (GRAM) with a dynamic scaling suitable for the simulation of fault and fracture processes in analogue experiments. The proposed material is composed of silica sand and hemihydrate powder and is suitable to form cohesive aggregates capable of deforming by tensile and shear failure under variable stress conditions. Based on dynamical shear tests, GRAM is characterized by a similar stress-strain curve as dry silica sand, has a cohesive strength of 7.88 kPa and an average density of 1.36 g cm−3. The derived geometrical scaling factor is 1 cm in model = 10.65 m in nature. For a large-scale test, GRAM material was applied in strike-slip analogue experiments. Early results demonstrate the potential of GRAM to simulate fault and fracture processes, and their interaction in fault zones and damage zones during different stages of fault evolution in dynamically scaled analogue experiments.

We show that two-dimensionally coupled optical parametric oscillator pulses capture the signature of the exact phase transition of the two-dimensional Ising model rather than that of a mean-field one.

Identifying pentagons and heptagons in graphene nanoflake (GNF) structures at the atomic scale is important to completely understand the chemical and physical properties of these materials. Herein, we used X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy to analyze the spectral features of GNFs according to the position of pentagons and heptagons introduced onto their zigzag and armchair edges. The XPS peak maxima were shifted to higher binding energies by introducing the pentagons or heptagons on armchair rather than zigzag edges, and the structures could be distinguished depending on the positions of the introduced pentagons or heptagons. Raman spectroscopic analyses also revealed that the position of edges with introduced pentagons or heptagons could also be identified using Raman spectroscopy, with characteristic bands appearing at 800-1200 cm-1, following the introduction of either pentagons or heptagons on armchair edges. This precise spectroscopic identification of pentagons and heptagons in GNFs provides the groundwork for the analysis of graphene-related materials.

Description, We constructed a large optical computer based on optical parametric oscillators coupled via measurement and feedback., Computers based on physical systems are increasingly anticipated to overcome the impending limitations on digital computer performance. One such computer is a coherent Ising machine (CIM) for solving combinatorial optimization problems. Here, we report a CIM with 100,512 degenerate optical parametric oscillator pulses working as the Ising spins. We show that the CIM delivers fine solutions to maximum cut problems of 100,000-node graphs drastically faster than standard simulated annealing. Moreover, the CIM, when operated near the phase transition point, provides some extremely good solutions and a very broad distribution. This characteristic will be useful for applications that require fast random sampling such as machine learning.

We describe an uncommon case of acute coils migration with significant occlusion of M3 branch and our management of this complication. Ballon-assisted coil placement was performed for an unruptured intracavernous internal carotid artery aneurysm in a 62-year-old woman. After coil placement and balloon deflection, we observed coils migration with significant occlusion of M3 branch. After early clinical deterioration without other neurological symptoms, we decided to perform superficial temporal artery-middle cerebral artery (STA-MCA) bypass to ensure blood flow distal to the occlusion. The patient was discharged without neurological deficit. To the best of our knowledge, this is the first case report about STA-MCA bypass to treat acute coils migration. This technique could represent a successful rescue therapy in case of acute coils migration that cannot be retrieved by endovascular tools or in case where distal and deep location of migrated coils controindicate surgical removal.

Because perovskite crystals exhibit unique magnetic, conductive, and optical properties, they have been the subject of many fundamental investigations in various research fields. However, investigations related to their use as optoelectronic device materials are still in their early days. Regarding oxide perovskites, which have been investigated for a long time, the efficiency of photoluminescence (PL) induced by band-to-band transitions is extremely low because of the localized nature of the carriers in these materials. On the other hand, halide perovskites exhibit a highly efficient band-edge PL attributable to the recombination of delocalized photocarriers. Therefore, it is expected that this class of high-quality materials will be advantageous for optoelectronic devices such as solar cells and light-emitting diodes. In this Minireview, we discuss various aspects of the PL properties and carrier dynamics of SrTiO3 and CH3 NH3 PbX3 (X=I, Br), which are representative oxide and halide perovskites.

Background: Microsurgical aneurysm (MSA) clipping is considered as the standard therapy with the endovascular coiling. Microsurgical clipping is considered superior to endovascular in terms of the recurrence rate. The management of recurrent aneurysm following previous microsurgical clipping is challenging. The management of recurrent aneurysm following previous microsurgical clipping is challenging. This study aims to explore the management of recurrent aneurysm of the anterior communicating artery (ACoM). Materials and Methods: This is a case series of three elder women who had a recurrence of ACoM aneurysm after MSA clipping. All the three patients were operated with microsurgical clipping. We studied the preoperative images of the first surgery of all the patients. The detailed case-by-case analysis was performed based on preoperative, postoperative, and follow-up radiologic examinations and operative findings. Results: All three patients who had a recurrence after MSA clipping of ACoM aneurysm and were asymptomatic. At presentation, they were diagnosed at the postoperative imaging at follow-up. The earliest recurrence was 1 year while in one patient; the recurrence was detected 8 years after the initial MSA clipping. The cerebral aneurysms were posteriorly directed in the initial preoperative images in all the cases. Conclusion: This study revealed the recurrence as the residual neck or the enlargement of the aneurysm even after MSA in these cases of ACoM aneurysm. Even with the complete clipping, there can be recurrence at the clip site due to the change in hemodynamics over the time. We should follow-up the patients regularly even after microsurgical clipping.

Introduction: Microsurgical clipping and Endovascular coiling (EC) are both effective alternatives in the management of intracranial aneurysms. EC has been shown to be associated with the risk of recurrent aneurysm (RA) growth. Considering the minimally invasive nature of this procedure, the management of intracranial aneurysms has been skewed toward EC, especially in the developed world. In this scenario, there has been an upsurge of RAs after EC. Since the optimal management of these RAs has not been defined, they pose a unique challenge to the treating surgeons. Aims and Objectives: The aim of this study is to elucidate the optimal management of RAs after EC. Materials and Methods: Medical records of all patients who underwent surgery for RAs were reviewed from the period January 2014 to March 2019. The demographic and angiographic patterns of the patients and operative techniques and complications were studied. The outcome was dichotomized into good and bad depending on the Glasgow outcome scale (GOS). Results: There were four cases of RAs operated in our institution between the above-mentioned period. There were varied differences between the initial coiling and time to recurrences. All four patients were operated under neuromonitoring. Three underwent clipping and one patient underwent clipping with bypass. All four patients had good outcome with a GOS of 5/5. Conclusion: Operations for RAs constitute many technical challenges and require a lot of expertise. Such surgeries are recommended in high-volume centers, with sufficient experience in both clipping and cerebral bypass.

Basilar apex aneurysms constitute 5%–8% of all intracranial aneurysms. Microsurgical clipping of basilar tip aneurysms is still advocated for as it is safe, especially for unruptured basilar tip aneurysms which have a low risk of postoperative mortality or morbidity. Careful patient preparation is needed preoperatively because the risk of intraoperative rupture is significant. Good surgical techniques should be applied. The skill will need to be preserved as endovascular surgery becomes more popular.This is a case of basilar tip aneurysm managed by clipping through the anterior temporal approach, followed by a review of the literature.

Objective To examine the effect of permanent salvage brachytherapy in prostate cancer patients suffering recurrence after three-dimensional conformal external beam radiotherapy. Methods The ultra-focal (target lesion alone), hemi-lobe (within a hemi-lobe) or focused whole-gland (focusing on the lesion, but extending into the whole gland) pattern was selected based on the Gleason score for the targeted biopsy, the numbers of positive cores in the targeted and systematic biopsies, and the locations of the positive cores. Novel dosimetry criteria derived from three-dimensional cancer mapping, which was based on targeted magnetic resonance imaging/transrectal ultrasound fusion biopsies, were used in these cases. Results Permanent salvage brachytherapy was carried out in 13 patients who suffered prostate-specific antigen failure (prostate-specific antigen 2.1-6.8 ng/mL; age range 57-75 years; Gleason score ≤7 [n = 10], Gleason score ≥8 [n = 2] and Gleason score not available [n = 1]) since 2012. The targeted biopsy showed a single focus in three patients. The ultra-focal, hemi-lobe and focused whole-gland patterns were chosen in three, five and five patients, respectively. During the follow-up period (median duration 48 months), prostate-specific antigen failure occurred in zero of three, one of five and three of five of the patients treated with the ultra-focal, hemi-lobe and focused whole-gland patterns, respectively. The 4-year biochemical recurrence-free survival rate was 74%. No grade 3-4 adverse intestinal or urological events occurred. Conclusions Targeted fusion biopsy-based three-dimensional cancer mapping should be used for permanent salvage brachytherapy treatment planning to reduce the incidence of treatment-related adverse events while maintaining good oncological outcomes.

OBJECTIVES To determine the safety and efficacy of the combined regimen of paclitaxel and ifosfamide plus nedaplatin for patients with refractory or relapsed germ cell tumors and impaired renal function. METHODS Of a total of 68 patients who received paclitaxel, ifosfamide and nedaplatin chemotherapy for germ cell tumors, those with an estimated glomerular filtration rate

Bilateral cavernous carotid aneurysm (CCA) is a rare entity. Its association with connective tissue disorder makes the diagnosis and treatment of symptomatic patient an enigma. We present a case report of a 25-year-old female medical student presented to us with bilateral spontaneous atypically symptomatic CCA with incidentally diagnosed case of Ehlers–Danlos syndrome. Both surgical and endovascular options of treatment were weighed and were ultimately treated satisfactorily by high-flow bypass with carotid artery ligation with an insurance bypass.

Knowledge of the strength of sediments overlying sub-seafloor gas-hydrate deposits is crucial for predicting borehole and seafloor stability during hydrate extraction. Ideally, sediment strength should be determined along a continuous downhole profile from the seafloor to the hydrate reservoir, but few such profiles have been obtained. In this study we used cores retrieved at Site NGHP-02-23 in the Krishna–Godavari Basin in unconfined penetration tests on split cores and in triaxial deformation experiments on hydrate-free sediment samples. Although penetrometer tests identified relatively low strength (70–250 kPa) likely due to hydrate dissociation in the hydrate-bearing interval 90–300 m below seafloor (mbsf), sediment strength exceeded 350 kPa in the intervals 140–170 and 250–270 mbsf, each of which lies just above a zone of high gas-hydrate concentration. The average stress ratio of triaxial strength at 4% axial strain to effective mean stress (qe=4%/p’) of hydrate-free silts was about 0.67 throughout the Hole. An exception to this trend was in fine sands from 280 mbsf in the deeper gas-hydrate zone, where the stress ratios were greater than 1.0. The stress ratios of hydrate-bearing sediments in the deeper gas-hydrate zone that were reported from the pressure-core measurements were far greater than those of any hydrate-free sediments for a given effective mean stress. The high-strength intervals in silty sediments we identified by the penetration tests could be associated with zones of high hydrate concentration. Because high-strength layers in fine-grained silty sediments commonly exhibit lower permeability than sandy layers (potential hydrate-host), they may act as seals that assist the precipitation of hydrate below them.

We estimate the rate of upward pore fluid flow and chlorinity (Cl−) concentrations at depth through a joint analysis of Cl− concentration and temperature versus depth profiles obtained from gas hydrate related test sites drilled and cored in the Krishna-Godavari Basin off the eastern coast of India. Cl−, measured on conventional core samples, decreases with depth at all sites but some of the Cl−profiles show a prominent convex shape, whereas in situ temperature profiles, obtained by the Advanced Piston Coring Temperature probe, are mostly linear at all sites established during the National Gas Hydrate Program 02 Expedition (NGHP-02). Assuming a one-dimensional, time-dependent model for the advection of pore fluid including the sedimentation effect and depth-dependent diffusivity, we estimate darcy velocity and the Cl− concentrations at depth. The best-fit darcy velocity of 1.2–1.6 × 10−11 m/s was estimated for the sites along the crest of the regional anticlinal structure in the NGHP-02 Area B, which was significantly faster than those on the flanks of the anticline. Because the thermal diffusion coefficient is much larger than the chloride ion diffusion coefficient, estimated darcy velocities are not great enough to generate nonlinear temperature profiles with depth, which is consistent with observed linear thermal profiles.

The Indian National Gas Hydrate Program Expedition 02 (NGHP-02) was designed to study the occurrence of gas hydrate along the passive continental margin of the Indian Peninsula in the Bay of Bengal. Twelve holes were logged and measured with logging-while-drilling (LWD) and five holes were cored in Area-B of NGHP-02. The LWD and coring results in Area-B helped to understand the geological significance of sequence stratigraphy in Krishna-Godavari Basin and identified the occurrence of gas hydrate. This study summarized the log- and litho-units in Area-B and establish three integrated units based on the core-log-seismic integration. Most of the downhole log and core inferred gas hydrate occurrences are in the Late Miocene Integrated-Unit B with several sets of reservoir sections exhibiting favorable conditions for hosting gas hydrate. The gas hydrates reservoirs associated with reflectors R1 and R2 were identified and the R1 reservoirs are characterized by fracture- and pore-filling gas hydrate, and the R2 is in sand-rich sediments with pore-filling gas hydrate at high saturations. The thickness variations associated with the R1 and R2 are possibly associated with the development anticlinal structure and are likely related to syn-sedimentary growth of the folding structures. Major gas hydrate zones exist in and around the R1 and R2 near the BSR depth, and mostly have coincident with the fractures and mass-transport deposits. The spatial distribution of gas hydrate in the R1 and R2 reservoirs is highly influenced by the anticlinal structure. This study can be considered a good case for the future gas hydrate studies and explorations in the nearby areas.

Physical properties like porosity and density are important parameters for size estimations of fossil fuel reservoir in host sediments and rocks. X-ray CT based imaging and subsequent analysis of the images by using various techniques for estimations of these properties of host rocks and sediments has been attempted. However, most of those techniques tend to be biased and subjective due to complications in image processing. Here we describe a new procedure for estimating porosity and density without processing the XCT images, but using the raw data that are used for producing the images. In this study, large-size cylindrical core samples (up to 150 cm long and 6.6 cm diameter) were imaged in a matter of minutes by using a medical XCT scanner soon after their recovery from seafloor onboard drillship in order to record as realistic as possible condition of hydrate-bearing sediments. Despite some uncertainty in relative volumes of solid, liquid and gas phases at voxel level, the results obtained by this rapid and non-destructive procedure are in good agreement with those obtained by time- and sample-consuming conventional methods of physical property measurements.

Gas hydrate-bearing layers are normally identified by a seismic imaged bottom simulating reflectors (BSR) or by downhole log responses because of their high acoustic velocity and electric resistivity compared to surrounding formations. These gas hydrate characteristics can also result in contrasting in-situ formation compressive strengths. Here, we describe gas hydrate-bearing layers based on equivalent strength (EST), which relates to in-situ compressive strength, in five exploration boreholes drilled during the Indian National Gas Hydrate Program Expedition 02 (NGHP-02). For Site NGHP-02-23, a representative site for those that were established during NGHP-02, the EST evaluated from drilling parameters shows a constant trend of ∼2 MPa, with some strong peak values in the 0–271.4 m-below-seafloor (mbsf) interval, and a sudden increase up to 4 MPa above the BSR depth (271.4–290.0 mbsf). Below the BSR, the EST stays at ∼2 MPa to the bottom of the hole (378 mbsf). Comparing the EST with logging data and a core sample description suggests that the EST depth profiles reflect the formation lithology and gas hydrate content. The EST increases in sand-rich and gas hydrate-bearing zone. In the lower gas hydrate layers in particular, the EST curve shows the same approximate trend with that of P-wave velocity and resistivity measured during downhole logging. Similar relationships between EST, hydrate layer, and log responses are confirmed in other four sites drilled nearby in NGHP-02 Area B. These results suggest that the EST, as a proxy for in-situ formation strength, can indicate the location and extent of the gas hydrate as well as borehole logging. Although the EST was calculated after drilling, utilizing the recorded surface drilling parameters (weight on bit, top drive torque, RPM and rate of penetration) in this study, the EST can be acquired during drilling using real-time drilling parameters. In addition, the EST only requires drilling performance data without any additional tools or measurements, making it a simple and economical tool for the exploration of gas hydrates.

The National Gas Hydrate Program Expedition 02 (NGHP-02) was designed to examine gas hydrate occurrences off the eastern margin of the Indian Peninsula. Twelve holes were logged with logging-while-drilling (LWD) tools and nine holes at five sites were cored in Area-B of NGHP-02. Five logging units were defined based on the characteristics in logging data responses. Distinctive Logging Units R1 and R2 characterized by high gamma ray log values and composed of quartz and biotite-rich medium sized sand grain units that act as gas hydrate resevoirs and correlated to strong seismic reflectors. Hydrate-bearing intervals can be identified by resistivity and sonic velocity logs and classified into pore-filling type, fracture-filling type, and a mixture of pore- and fracture-filling types based on borehole image characteristics. Pore-filling type gas hydrate is typically developed in the case where the depths of R1 and/or R2 is close to the seismic inferred bottom simulating reflector (BSR). Fracture-filling type hydrates associated the R1 section occur above the BSR associated with the anticline in Area-B. The occurrence of pore-filling and fracture-filling gas hydrate represent different processes of hydrate formation related to the regional geological structure. The stratigraphic layered pore-filling gas hydrate occurrences are generated along often dipping sand layers, which are also conduits for methane-bearing fluid migrating from below the BSR in many settings. Fracture-filling type gas hydrate is an alternative mechanism for the occurrence of gas hydrate in mudstone-rich sediments above the BSR and found associated with the anticline in Area-B. This structural constraint of the hydrate-bearing fractures in the Area-B anticline suggest that the fracture dominated reservoirs possibly formed by anticlinal flexure, and the upward flow of methane-bearing fluids along porous sedimentary layers and the subsequent formation of pore-filling gas hydrate occurrences account for the range of gas hydrate accumulations discovered during NGHP-02.

The primary objectives of the India National Gas Hydrate Program Expedition 02 (NGHP-02) were to obtain new data on the occurrence of gas hydrate systems and to advance the understanding of the controls on the formation of gas hydrate accumulations in the offshore of India. In accordance with the ultimate overall goal of the NGHP effort to assess the energy resource potential of marine gas hydrates in India, particular focus was placed on the exploration and evaluation of gas hydrate occurrences at high saturations in sand-rich systems. NGHP-02 operations were conducted from 3-March-2015 to 28-July-2015 off the eastern coast of India and included logging while drilling (LWD) operations at 25 locations, and coring and wireline logging operations at 10 locations, in the Krishna-Godavari and Mahanadi Basins. The formation of highly concentrated gas hydrate accumulations, which are more suitable for energy extraction, requires the presence of relatively coarse-grained sediments with porosity needed to support the migration and accumulation of gas, and the nucleation of gas hydrate. The results of downhole logging, coring and formation pressure testing operations during NGHP-02 have confirmed the presence of extensive sand-rich depositional systems throughout the deepwater portions of the Krishna-Godavari and Mahanadi Basins. Two areas of the Krishna-Godavari Basin, referred to as Areas B and C, contain substantial gas hydrate accumulations in sand-rich systems and therefore represent ideal candidate sites for future gas hydrate production testing. This summary and technical report includes a comprehensive synthesis of the geologic, geophysical, geochemical, and physical property data acquired during NGHP-02 as it relates to the controls on gas hydrate occurrence, particularly with regards to sand-hosted accumulations. In the Mahanadi Basin, despite the confirmation of extensive reservoir capacity, gas supply at the NGHP-02 sites was insufficient to charge the reservoirs with gas hydrates. In the Krishna-Godavari Basin, extensive reservoir systems were confirmed with sediment grain-sizes ranging from coarse-silts to gravels. These reservoirs range from fully- to partially-filled with gas hydrate. The gas is determined to be from only microbial sources, and in part migrated into the reservoirs from deeper systems. The controls on gas hydrate occurrence are complex and varied; and include substantial reservoir heterogeneity and sufficient permeability throughout the reservoirs and seals that allowed pervasive fluid flow into and through the hydrate-bearing systems. These discoveries are the most significant confirmation of the exploration approach that focuses on direct detection of hydrate reservoirs supported by comprehensive petroleum systems analyses.

The existence of overpressure in shallow sediments, which is often constrained by hydraulic properties, influences the gas-hydrate formation process and gas production. Porosity, permeability, and grain size measurements in laboratory experiments were conducted on core samples from gas-hydrate-bearing regions offshore from the Krishna-Godavari Basin, eastern India. Porosity was found to decrease with increasing effective stress; this is explained by the exponential decay curve along which porosity decreases from 65 % at 0 MPa to 40 % at 10 MPa. Permeability and the corresponding hydraulic diffusivity decrease from 10−17 to less than 10−18 m2 and from 10−7 to 10−8 m2/s at 0.5 and 5 MPa, respectively. Grain sizes were larger and the sand fraction more scattered in channel-filled sediment sites compared to slope sediment sites. The preconsolidation stresses evaluated from consolidation curves indicate the absence of overpressure at shallow depths. In contrast, a comparison of ship-board measurements and standard compaction curves suggested that measured porosity was higher than the predicted porosity at greater depths. These porosity anomalies are interpreted as a sign of overpressure that approaches near lithostatic values at greater depths in slope sediment sites. A one-dimensional sedimentation model recreated overpressure profiles similar to those predicted by porosity gaps, under the assumption of large basial fluid influx or lower permeability than that derived from laboratory data. The modeling results suggest that near-hydrostatic pressure at shallow depths and significant overpressure at greater depths proposed by the porosity gap method is explained by the non-linearity of transport properties. The relatively small overpressure generation in channel-filled sites compared with slope sites can be explained by the higher permeability due to coarser grain size and larger sand fraction and by the smaller basal influx. On the contrary, considerably large basal influx associated with clay mineral dehydration and methane gas supply from deep sediments was expected to promote overpressure at slope sites, which is confirmed by Cl− concentration-depth profiles.

Background Mirror aneurysms represent 2 adjacent arterial protrusions. Although the size is considered a major risk factor in terms of rupture, sometimes it is the smaller aneurysm that ruptures. Here, we present the contemporary management of mirror distal anterior cerebral artery (DACA) aneurysms associated with multiple aneurysms. Computational fluid dynamic (CFD) analysis was performed when assessing multiple aneurysms using Hemoscope, version 2015. Case Description Among multiple aneurysms, a mirror A2/A3 DACA aneurysm was found in a single patient. Surgical treatment was provided for all aneurysms through a single-stage procedure. The left ruptured A2/A3 aneurysm was smaller compared with the right (7.5 × 3.5 mm/10.8 × 3.2 mm). CFD showed greater wall pressure (WP) in the left ruptured A2/A3 aneurysm (left A2/A3 WP 84,000–84,402 Inst. mm Hg/right A2/3 WP 84,224–84,315). WP in the left middle cerebral artery and anterior communicating artery aneurysms showed lesser values compared with the ruptured aneurysm (WP upper values 84,361 and 84,367, respectively). Wall shear stress showed low values for all aneurysms with the lowest flow rate values in the left A2/A3 aneurysm. Conclusions In cases of ruptured mirror aneurysms followed by the presence of intracerebral hematoma, surgery is considered the primary option with the best results. A one-stage dual craniotomy procedure was found safe in the associated treatment of other multiple aneurysms. At present, the size of the aneurysm, the hemodynamic influence, and the local configuration are all considerations during the preoperative assessment of multiple aneurysm cases. According to our knowledge, this article presents the first CFD analysis of mirror DACA aneurysms associated with aneurysm multiplicity.