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An accurate prediction method of cavitation surge is desired to design a reliable turbopump for rocket engines that allow complex operational sequences such as controlled reentry and landing. Therefore, the paper aims to develop a novel model that enables accurate predictions of both frequency and onset of cavitation surge by considering dynamic characteristics of cavitation compliance K and mass flow gain factor M. The paper conducts both experimental and numerical studies in an inducer known to cause cavitation surge. First, characteristics of cavitation surge including frequency and occurrence conditions are experimentally surveyed. Secondary, K and M for the studied inducer are numerically obtained by steady RANS simulations. Then, the one-dimensional model is initially established based on the premises acquired by performed experiments and applied to cavitation surge predictions using quasi-statically evaluated K and M. As a result of comparisons with experiments, the cavitation surge frequency is adequately evaluated by the established model, whereas the cavitation surge onset fails to be estimated only using quasi-static parameters. The new model is thus proposed by including dynamic characteristics of K and M, and it is mathematically clarified that phase properties of K and M may play a key role to trigger cavitation surge. By presuming adequate values of dynamic characteristics based on past literatures, consequently, the developed model succeeds in accurate predictions of the cavitation surge onset in the experiment. This evidences that dynamic characteristics of K and M are essential to predict cavitation surge quantitatively.

In recent years, various types of liquid rocket engines have been developed to achieve different types of mission, and modern rocket engines are required to operate at different conditions depending on flight situations such as launch and landing. Thus, rocket engines are required to be more reliable and robust. One of the key components for a rocket engine to enable flexible operating conditions is a turbine since it determines a power of feed-line systems and an efficiency of rocket system itself. To fulfill the requested output of the entire systems, an appropriate design of the turbine, including the selection of full/partial admission configurations, is of crucial importance. On the other hand, the development of supersonic turbines in turbo-pumps remains a challenge due to their complex internal flow structures and systems with high rotational speed. Furthermore, it is necessary to achieve high performance and stable operations under extensive operating range in respect of innovative transport technologies including the development of reusable launch vehicles. However, detailed flow characteristics at off-design conditions of supersonic turbines are yet to be fully understood. Therefore, this paper aims to study internal flow characteristics and performance of a supersonic turbine at different operating points. The present study first demonstrates the comparisons of 3D RANS simulation results of the selected supersonic turbine (JAXA subscale M-1 turbine) consisting of two stages with full admission nozzles and partial admission nozzles, where the experimental results with the partial admission configuration are available to validate the simulation results. The simulations are conducted with full stages and the entire circumferential configuration at 5 different operating conditions defined by the velocity ratio (the ratio between the turbine rotational velocity and isentropic velocity at the turbine outlet) including the nominal condition. The internal flow structures under off-design operations for both full and partial admission nozzle configurations are investigated to address profound features of the flow field at off-design operations in a supersonic turbine. The analysis is furthermore extended to reveal the mechanisms of the energy loss by comparing the results of the full admission and two different configurations of the partial admission nozzles at different operating conditions. As a result, an empirical method to determine nozzle and ventilation loss curves based on velocity ratio is proposed, and also it is demonstrated that these curves can be applied to predict energy loss of various partial admission configurations at different operating conditions.

Brain functional connectivity in the resting-state represents intrinsic functional states and correlates with cognitive performance. In patients with schizophrenia, reports on the relationships between forms of functional disconnectivity in local areas and cognitive disability have used resting-state functional magnetic resonance imaging data. Meanwhile, cognitive deficits in relation to inter-network forms of functional connectivity on a large scale are not well understood. This study examines cognitive functions in relation to the number of resting-state inter-network forms of functional connectivity focusing on task-positive networks (fronto-parietal network [FPN] and cingulo-opercular network [CON]) and task-negative network (default mode network [DMN]). We compare patients with schizophrenia (SCH group) and healthy controls (HC group). We conducted a functional network analysis by applying graph theory and evaluated cognitive functions using the Brief Assessment of Cognition in Schizophrenia. The number of forms of functional connectivity between FPN and DMN and between CON and DMN were significantly higher in SCH group than in HC group, and those in SCH group were also weakly correlated with their attention scores. It is suggested that fewer than typical functional segregations between task-positive and task-negative networks in SCH group relate to inefficient distribution of cognitive resources and low attentional abilities.

Objectives Eating disorders result in poor nutrition, poor physical conditions and even suicidality and mortality. Although polyunsaturated fatty acids (PUFAs) have attracted attention in the emerging field of nutritional psychiatry, their role in eating disorders remains unknown. This meta-analysis investigates the differences of PUFA levels between patients with eating disorders and healthy controls, and the potentially beneficial effects of PUFAs in such patients. Methods We conducted a systematic literature search and meta-analysis under the random effects model. Result Eleven studies were included in the current meta-analysis. Compared with controls, 379 patients with eating disorders had significantly higher plasma levels of alpha-linolenic acid, eicosapentaenoic acid, stearidonic acid, osbond acid, palmitoleic acid, oleic acid, and total omega-3 fatty acids; and lower levels of total omega-6 fatty acids and omega-6/omega-3 ratio. Eating disorders were associated with significantly higher red blood cell membrane levels of palmitoleic acid and oleic acid and lower levels of adrenic acid, arachidonic acid, and total omega-6 fatty acids. In addition, PUFA supplements were associated with a benefit to body weight outcomes but not disease severity and mood symptoms in interventional trials. Discussion This meta-analysis indicates abnormal levels of PUFAs in peripheral blood tissues in patients with eating disorders. The relationship between PUFAs and eating disorders should be interpreted cautiously considering the specific lipid metabolism under starvation state. To investigate the role of PUFAs on psychopathological and therapeutic effects in eating disorders, further larger clinical studies are warranted.

Objectives Subjective tinnitus loudness has been measured using loudness matches, which compare tinnitus loudness with pure tones from an audiometer. When patients compare the sound pressure of certain noises with the tinnitus loudness, however, there may be remarkable differences from the measurements according to loudness matches. Subjective loudness (SubL) is an estimation of the sound pressure of tinnitus loudness by comparison of noises considered to be most similar to tinnitus loudness of patient. We examine whether SubL is inferior to loudness matches in measurement of subjective tinnitus loudness. Design Single-group cross-sectional study. Patients Included in this study were a clinical group of 111 patients with the chief complaint of subjective tinnitus. Seven of the 111 patients were excluded due to missing audiometry or questionnaire data. Methods Patients assessed the tinnitus loudness and related distress using visual analogue scales (VAS-L and VAS-S) and answered the Tinnitus Handicap Inventory (THI). Hearing acuity, tinnitus pitch, and loudness were then measured using an audiometer. Results VAS-L, VAS-S, and THI scores significantly correlated with loudness match using Goodwin's method (SL2) and SubL. Subgroup analysis based on patient ages indicated that all correlations of SL2 with VAS-L, VAS-S, and THI scores were no longer seen in patients more than 60 years of age. Meanwhile, SubL correlated with VAS-L, VAS-S, and THI scores in all subgroups. Conclusions SubL was a good reflection of self-reported loudness and distress of tinnitus. It may therefore be a simple and easy means of assessing tinnitus loudness and associated distress during pre-examination without an audiometer.

2017年7月19日（水）午後3時より、グローバル地域文化学部完成記念シンポジウム「GとRの結び方--グローバル地域文化学部という挑戦」を志高館にて開催しました。一橋大学大学院言語社会研究科教授の鵜飼哲氏をお招きし、「友愛の地政学」との演題で基調講演をいただき、鵜飼氏の講演を受けて、本学教員の小野文生、尹慧瑛氏の司会のもと、鵜飼氏、本学教員の伊藤玄吾、王柳蘭、宇佐見耕一氏による総合討議がなされ、その後、参加者との間で活発な議論が交わされました。

Summary Objective Elucidation of abnormal connections throughout the whole brain is necessary to understand temporal lobe epilepsy (TLE). We examined abnormalities in whole‐brain white matter integrity and their relationship with duration of illness in patients with TLE. Methods The subjects were 15 patients with TLE and 17 healthy controls. Mean duration of illness in the TLE group was 21.6 years. Tract‐based spatial statistics (TBSS) were used for diffusion tensor imaging (DTI) analysis. Four diffusion tensor metrics, that is, fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were calculated and then examined for differences between the TLE and healthy control groups. We also examined for correlations between DTI parameters and duration of illness in the TLE group. Results In the TLE group, compared with the healthy control group, FA was reduced, and MD and RD were increased, not only in the limbic and temporal lobe regions and their directly connecting regions in both hemispheres, but also in remote white matter regions. Duration of illness showed a significant negative correlation with mean whole‐brain FA and a significant positive correlation with both mean whole‐brain MD and RD. Brain regions showing correlation between disease duration and DTI metrics also extended to the limbic area and its connecting regions, and to remote white matter regions. Significance The results of this study suggest that widespread abnormalities in white matter integrity in patients with TLE are associated with long‐term disease.

Although diffusion tensor imaging (DTI) have revealed brain abnormalities in bipolar disorder (BD) subjects, DTI methods might not detect disease-related abnormalities in the white matter (WM) where nerve fibers are crossing. We investigated BD myelin-related abnormal brain regions in both gray matter and WM for 29 BD and 33 healthy control (HC) participants using T1-weighted (T1w)/T2-weighted (T2w) ratio images that increase myelin-related contrast irrespective of nerve fiber orientation. To check effect of the brain volume, the results were compared with those of voxel-based morphometry (VBM). We found significantly lower T1w/T2w signal intensity in broad WM regions in BD subjects, including the corpus callosum, corona radiata, internal capsule, middle cerebellar peduncle and cerebellum. Regional volume reduction was found in the WM bilateral posterior thalami and retrolenticular part of the internal capsules of BD subjects. We also performed tract-based spatial statistics (TBSS) in 25 BD and 24 HC participants and compared those for the T1w/T2w ratio images. Both methods detected the BD corpus callosum abnormality. Further, the ratio images detected the corona radiata and the cerebellar abnormality in BD. These results suggest that T1w/T2w ratio image analysis could take a complementary role with the DTI method in elucidating myelin-related abnormalities in BD.

The cover image is based on the Original Research Microstructural abnormalities in callosal fibers and their relationship with cognitive function in schizophrenia: A tract‐specific analysis study by Yuji Ohoshi et al., DOI: 10.1002/brb3.1357. [Image: see text]

The clinical introduction of rTMS for the treatment of depression is now progressing in Japan. On the basis of the successful results of a large-scale RCT, the US FDA approved an rTMS device in 2008, and four rTMS devices are now approved and used in several countries and the EC. The results of the meta-analysis of RCTs and the real-world naturalistic observa- tional studies show beneficial effects on treatment-resistant depression. The rTMS is generally well-tolerated and safe, but has a risk of seizure, with an estimated rate of approximately one in 1,000 patients. The rTMS is thought to be an effective treatment for those unable to benefit from initial antidepressant medication.

ObjectiveControlling hyperactive and mixed delirium is extremely important for the continuation of cancer treatment in palliative care. In general, oral antipsychotics are the first-line drug therapy for delirium; however, oral administration is problematic in patients presenting dysphagia. In this case report, we describe an end-stage cancer patient with aphagia who developed delirium and responded to sublingual antipsychotic asenapine for treating delirium. We also discuss the effectiveness of asenapine in hyperactive delirium as well as its usefulness for treating delirium in palliative care.MethodA cancer patient with delirium was treated with several oral antipsychotics commonly used to treat delirium but did not respond to any of them. The patient subsequently developed aphagia with progression of the disease. Sublingual asenapine was therefore given to treat delirium.ResultAsenapine was effective in treating delirium without causing any obvious side effects.Significance of resultsIn the present case, asenapine was effective in treating hyperactive delirium that did not respond to commonly used antipsychotics. Because asenapine is a sublingual tablet, it can be used in patients with dysphagia and aphagia. In addition, this drug is anticipated to diminish the burden of end-stage patients from taking oral medications. Furthermore, its management is easier compared with injections, and can therefore also be easily used in homecare patients. Based on these perspectives, asenapine may become an important option for treating delirium in palliative care.

We report an 83-year-old woman with atypical senile dementia with Fahr-type calcification. Brain computed tomography demonstrated asymmetrical calcification predominant in the basal ganglia on the right side and pronounced diffuse cortical atrophy in the frontotemporal areas. The patient was clinically diagnosed with diffuse neurofibrillary tangles with calcification. Brain single photon emission computed tomography findings revealed that cerebral blood flow was reduced on the right side, as compared with the left side, in widespread areas. Hemispheric asymmetry in both calcification and cerebral blood flow suggests a relationship between calcification and vascular changes.

Background The corpus callosum modulates interhemispheric communication and cognitive processes. It has been suggested that white matter abnormalities in the corpus callosum are related to the pathophysiology of major depressive disorder (MDD) and bipolar disorder (BD). The aim of this study was to examine microstructural abnormalities in callosal fibers separated by their connection to functional brain regions and determine the relationship of these abnormalities with cognitive function in MDD and BD. Methods The subjects were 18 patients with MDD, 20 patients with BD, and 21 healthy controls. The callosal fibers were divided into 6 segments based on their cortical projection using tract-specific analysis of diffusion tensor imaging. We examined differences in the fractional anisotropy (FA) of callosal fibers in six segments among the three subject groups and examined the correlation between the FA in each segment and cognitive performance in the 3 groups. Results The FA of anterior callosal fibers were reduced significantly in the MDD and BD groups compared to those in the HC group, and the FA of anterior callosal fibers correlated significantly with the raw scores of the digit sequencing task and symbol coding in the MDD group. Limitations The patients were medicated at the time of scanning, and the MDD and BD groups were not matched for symptom severity. Conclusions Our results suggest that MDD and BD have similar microstructural abnormalities in anterior callosal fibers connecting bilateral frontal cortices, and these abnormalities may be related to impairment of working memory and attention in MDD.

Autoimmune autonomic ganglionopathy (AAG) is a rare acquired immune-mediated disorder that leads to autonomic failure. It is sometimes complicated by mental and behavioral symptoms. We report a case of 72-year-old male with AAG who was admitted to the psychiatric department for prolonged severe delirium. Repeated loss of consciousness attributed to severe orthostatic hypotension disturbed recovery from delirium. In addition, intracerebral hemorrhage occurred during hospitalization, and this cerebrovascular event may have been substantially affected by unstable blood pressure due to AAG. This case suggests importance of differential diagnosis of AAG in patients with mental and behavioral symptoms accompanying severe autonomic failure.