A topspin rate exceeding 110 rps reduces the ball time of arrival to the opponent: a table tennis rally study.

This study experimentally investigated the factors affecting the time a table tennis ball with topspin takes to reach the opponent. Six skilled young players and one coach performed topspin forehand strokes under the observation of three high-speed cameras. As the distribution of the participants' measurements was uneven, additional data were collected using a launching machine that could control the ball speed and spin. To verify the effect of the spin rate on speed decay by drag, the translational speed was measured at 0.15 s after passing the baseline (23 m/s); the balls with topspin ≥110 rps, close to participants' average (117 ± 29 rps) were 1.4 m/s faster than those with topspin ≤80 rps. The horizontal ball speed changed in the range of -3.1 to 2.6 m/s owing to table bounce. At topspins ≥110 rps the ball reached a point 1 m past the end line (estimated receiving position) 27 ± 5 ms faster than at topspins ≤80 rps, for the same initial speed. The relationship between spin rate and travel time was non-linear with boundaries at 80 and 110 rps. Therefore, maintaining a spin rate of ≥ 110 rps along with a high initial speed is an effective strategy for reducing the opponent's preparation time.

Safety and tolerability of aripiprazole in patients with psychosis associated with Parkinson's disease-Results of a multicenter open trial.

AIM: To evaluate the effect of aripiprazole on psychosis and motor function in Japanese Parkinson's disease patients. METHODS: Patients with Parkinson's disease and hallucinations and/or delusions were enrolled. They were administered aripiprazole 3 mg/day, with dosage increased or reduced as needed. Patients were evaluated using the Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression-Severity (CGI-S) scale, and Clinical Global Impression-Improvement scale for psychiatric response; Hoehn & Yahr staging and Unified Parkinson's Disease Rating Scale (UPDRS) part III for motor response; Mini-Mental State Examination (MMSE) and Frontal Assessment Battery (FAB) for cognitive response; and Schwab and England Activities of Daily Living scale for daily activities of patients, before and at 2, 4, and 12 weeks after initiation of open-label aripiprazole administration. This study was registered at the University Hospital Medical Information Network Center (registration number: UMIN000007711). RESULTS: Nine of the 24 enrolled patients discontinued the study. Among them, eight patients discontinued the trial on account of their worsening parkinsonian symptoms. There were no differences in age, disease duration, disease severity, and MMSE and FAB scores at baseline between patients who continued and discontinued the study. However, in patients who continued aripiprazole administration at 3 mg/day or less significantly improved BPRS, CGI-S scale, and UPDRS parts I and III scores. CONCLUSION: Significant improvements in hallucinations and delusions can be expected, although aripiprazole may aggravate parkinsonism in Parkinson's disease patients. Low-dose use of aripiprazole may be useful for managing Parkinson's disease patients with psychosis, but only with close observation of extrapyramidal symptoms.

[A case of tick-borne encephalitis without any sequelae].

A 43-year-old woman with a history of tick bite in the mountains in Hokkaido presented with a fever of 39°C, headache, and nausea. Cerebrospinal fluid findings indicated meningitis. On day 3 after admission, she presented with restlessness, disturbance of consciousness, and ataxic breathing, indicative of encephalitis. We administered steroid pulse therapy, tracheal intubation, and a respirator. Her symptoms improved gradually and she was able to breathe without the respirator on day 10 after admission. She was discharged on day 24 after admission with no sequelae. This is the fifth reported case of tick-borne encephalitis in Japan. In the previous four cases, the patients died or suffered severe sequelae. This is the first case without any sequelae in Japan.

[Burnout in Japanese neurologists: comparison of male and female physicians].

A questionnaire survey was conducted on 8,402 members of the Japanese Neurological Society to examine the current status and countermeasures for physician burnout, and 1,261 respondents (15.0%) responded. In this paper, we report the results of a comparison between male and female physicians. There was a significant difference in working and living conditions only for married people. It was confirmed that men work under stricter conditions in terms of working hours, and that the burden on women is heavier in the division of housework. Analysis using the Japanese Burnout Scale revealed no gender differences in overall scores, but as for factors related to burnout, in addition to factors common to both men and women, factors specific to men or women were clarified.

[Current and future strategies for burnout in Japanese neurologists].

To identify factors associated with burnout among Japanese physician and to use them in future measures, the Japanese Society of Neurology conducted a survey of neurologists on burnout using a web-based questionnaire in October 2019. A total of 1,261 respondents, 15.0% of the 8,402 members, responded to the survey. The mean of the subscales of the Japanese Burnout Scale was 2.86/5 points for emotional exhaustion, 2.21/5 points for depersonalization, and 3.17/5 points for lack of personal accomplishment. In addition, the burnout of our country's neurologists is not related to workloads such as working hours and the number of patients in charge, but also to a decreased meaningfulness and professional accomplishment. Therefore, it is necessary to take comprehensive measures to improve these issues at the individual, hospital, academic and national levels.

Biogas production management systems with model predictive control of anaerobic digestion processes.

We developed a biogas production management system to control biogas production by determining the feedstock inputs to the anaerobic digestion process according to fluctuations of the renewable energy supply. The developed system consists of three functions: a prediction model for the anaerobic digestion processes, a parameter-estimation system, and a feedstock-determination controller. A prediction model for the anaerobic digestion processes in a state-space representation was constructed for the input-output relationship of biogas generation from organic compounds and the state of methane fermentation. A parameter-estimation system that estimated the parameters included in the prediction model from actual operating process data was built based on adaptive identification theory. The feedstock-determination controller was established based on model predictive control as a method to control biogas production. From the results of the identification experiment, the least square estimator of the parameters converged as the training data increased, and a reliable parameter was given in 1 week. From the results of the numerical simulation and the control experiment, it was confirmed that the biogas production management system developed in this study had a high prediction accuracy and control performance.

Non-motor symptoms depending on motor severity in Japanese patients with Parkinson's disease: A multicenter cross-sectional study.

BACKGROUND: Although non-motor symptoms (NMS) in patients with Parkinson's disease (PD) often worsen as the severity of motor symptoms (MS) increases, few studies have assessed the associated factors of non-motor symptoms. OBJECTIVE: This study aims to determine whether the presence of NMS in PD patients is associated with or independent from the severity of MS considering confounders. METHODS: The registry of PD patients from seven facilities in Japan was used. Multiple logistic regression was performed with each domain and item of the Non-motor Symptoms Scale (NMSS) as objective variables. Severity of motor symptoms was assessed by Hoehn & Yahr stage (HY stage) as an explanatory variable. The analysis was adjusted for sex, age, disease duration, presence/absence of wearing off and dyskinesia, clinical phenotypes and Levodopa equivalent daily dose. RESULTS: A total of 1037 patients were analyzed. Analysis by NMSS domain showed higher odds ratios (ORs) in patients with higher HY stages compared with patients with lower HY stages for domains D1 (cardiovascular), D2 (sleep/fatigue), D3 (mood/apathy), D4 (perceptual problems/hallucinations), D5 (attention/memory), and D6 (gastrointestinal) (ORs: 1.54-2.72, P < .05). However, only domains D7 (urinary) and D8 (sexual dysfunction) were not associated with HY stage. Item 2 (fainting) and Item 14 (delusions) showed higher ORs in the HY stage 4-5 (ORs: 9.95 and 5.92, P < .05). CONCLUSIONS: Most NMS worsened with exacerbation of MS in PD patients, however some NMS domains were also affected with other factors. These findings contribute to the understanding of the clinical picture of PD and may improve personalized medicine and research in PD.

Adaptive identification of anaerobic digestion process for biogas production management systems.

To achieve the goals of sustainable development, supplies of renewable energy must be increased and methods of stable production developed. This study focused on the anaerobic digestion process using biomass as a raw material, which represents a renewable energy resource which is robust to environmental change and can be adjusted to suit supply and demand. A state-space model of the process was built in this study, consisting of two differential equations and one algebraic equation. The parameters included in the model are dependent on the operating conditions of the process. Automatic estimation of parameters from the input and output data of the process enables easy use of the model under any operating conditions. An adaptive-identifier control system was introduced as the parameter-estimation system, which made it possible to obtain the least squares estimate of parameters. When accumulated biogas generation per day was predicted using the model, goodness-of-fit analysis indicated an accuracy of over 80% in all cases, validating the model and estimated parameters. Future tasks will involve implementation of model predictive control into anaerobic digestion processes with the model and parameter-estimation system developed in this study.

Table tennis match analysis: a review.

In table tennis, many different approaches to scientific founded match analysis have been developed since the first ones in the 1960s. The aim of this paper is to give a review on some of the most acknowledged methods of match analysis in table tennis. The first chapter presents a historical overview of match analysis from all over the world. The second part reviews different approaches to match analysis in more detail, using the performance analysis classification of theoretical and practical performance analysis. The review includes the most actual theoretical performance analysis techniques in table tennis: performance indices, simulative approaches, momentum analysis, footwork analysis, and finally an approach which uses top expert knowledge for a comprehensive technical-tactical analysis. In the section of practical performance analysis, the paper presents two "best practice" examples describing performance analysis procedures of the two most successful countries of the last Olympics: China and Japan. The paper ends with a summary on the impact of the different approaches and gives an outlook on promising new developments.

A Shot Number Based Approach to Performance Analysis in Table Tennis.

The current study proposes a novel approach that improves the conventional performance analysis in table tennis by introducing the concept of frequency, or the number of shots, of each shot number. The improvements over the conventional method are as follows: better accuracy of the evaluation of skills and tactics of players, additional insights into scoring and returning skills and ease of understanding the results with a single criterion. The performance analysis of matches played at the 2012 Summer Olympics in London was conducted using the proposed method. The results showed some effects of the shot number and gender differences in table tennis. Furthermore, comparisons were made between Chinese players and players from other countries, what threw light on the skills and tactics of the Chinese players. The present findings demonstrate that the proposed method provides useful information and has some advantages over the conventional method.

Effect of Changing Table Tennis Ball Material from Celluloid to Plastic on the Post-Collision Ball Trajectory.

The official material used in table tennis balls was changed from celluloid to plastic, a material free of celluloid, in 2014. The purpose of this study was to understand the differences and similarities in the two types of ball materials by comparing their behavior upon collision with a table. The behavior of the balls before and after collision with a table, at various initial speeds ranging from 15 to 115 km/h, was captured using high-speed cameras. Velocities and spin rates before collision and velocities after collision were computed to calculate the coefficients of restitution and friction. Based on the computed variables, the post-collision trajectories of both balls were calculated by integrating the equation of motion of the ball for simulated service, smash and drive conditions with respect to time. The coefficients of restitution were higher for the plastic balls than the celluloid ones when the initial vertical velocities were higher. The coefficients of friction were higher for plastic balls when the initial horizontal contact point velocities were slower. Because of the differences in the material characteristics, the plastic ball trajectories of services with backspin and drives with great topspin were expected to be different from those of celluloid balls. Since the extent of differences between the two ball types varied depending on the initial conditions, testing at various initial conditions was suggested for comparing and understanding the characteristics of the balls.

Latitude and HLA-DRB1*04:05 independently influence disease severity in Japanese multiple sclerosis: a cross-sectional study.

BACKGROUND: Higher latitude and human leukocyte antigen (HLA)-DRB1*04:05 increase susceptibility to multiple sclerosis (MS) in the Japanese population, but their effects on disease severity are unknown. We aimed to clarify the effects of latitude and the HLA-DRB1 and HLA-DPB1 genes on disease severity in Japanese patients with MS. METHODS: We enrolled 247 MS patients and 159 healthy controls (HCs) from the northernmost main island of Japan, Hokkaido Island (42-45° north), and 187 MS patients and 235 HCs from the southern half (33-35° north) of the Japanese archipelago (33-45° north). We genotyped HLA-DRB1 and HLA-DPB1 alleles, compared demographic features, and analyzed factors contributing to differences in clinical and laboratory findings between MS patients from southern and northern Japan. The Multiple Sclerosis Severity Score (MSSS), which adjusts the Kurtzke's Expanded Disability Status Scale score according to disease duration, was used to estimate disease severity. RESULTS: The HLA-DRB1*04:05 and DRB1*15:01 alleles conferred susceptibility to MS in our Japanese population (p (corr) = 0.0004 and p (corr) = 0.0019, respectively). Southern patients had higher MSSS scores than northern patients (p = 0.003). Northern patients had higher frequencies of brain lesions meeting the Barkhof criteria (Barkhof brain lesions) and cerebrospinal fluid (CSF) IgG abnormalities than southern patients (p = 0.0012 and p < 0.0001, respectively). DRB1*04:05-positive MS patients had lower MSSS scores and lower frequencies of Barkhof brain lesions and CSF IgG abnormalities than DRB1*04:05-negative MS patients (p = 0.0415, p = 0.0026, and p < 0.0001, respectively). Multivariate analyses revealed that latitude and DRB1*04:05 were independently associated with the lowest quartile of MSSS and that latitude was positively associated with Barkhof brain lesions and CSF IgG abnormalities. DRB1*04:05 was negatively associated with these parameters. MSSS was decreased by 0.57 per DRB1*04:05 allele (p = 0.0198). CONCLUSIONS: Living at a higher latitude and carrying the DRB1*04:05 allele independently lessens MS symptom severity as defined by MSSS. However, these factors influence the frequency of Barkhof brain lesions and CSF IgG abnormalities in opposite ways; higher latitude increases the frequency of Barkhof brain lesions and CSF IgG abnormalities, whereas DRB1*04:05 decreases them.

Comparison of Different Symptom Assessment Scales for Multiple System Atrophy.

To identify the most sensitive scale for use in clinical trials on multiple system atrophy (MSA), a short and sensitive scale is needed for MSA clinical trials. Potential candidates are the Unified MSA Rating Scale (UMSARS), Scale for the Assessment and Rating of Ataxia (SARA), Berg Balance Scale (BBS), MSA Health-Related Quality of Life scale (MSA-QoL), and Scales for Outcomes in Parkinson's Disease-Autonomic questionnaire (SCOPA-AUT). We enrolled patients with MSA from eight hospitals in Hokkaido, Japan. Board-certified neurologists assessed each patient at 6-month intervals and scored them on the UMSARS, SARA, BBS, MSA-QoL, and SCOPA-AUT. Score changes were evaluated using the standardized response mean (SRM). The correlation between disease duration and each score was examined. The first evaluation was conducted on 85 patients (60 patients with MSA cerebellar ataxia dominant subtype [MSA-C] and 25 patients with MSA Parkinsonism-dominant subtype [MSA-P]). Sixty-nine patients were examined after 6 months and 63 patients after 12 months. The UMSARS Part 4 had the largest SRM after 6 months and the SARA after 12 months. SRMs for MSA-P, the shorter duration group, and the early-onset group were larger than were those for MSA-C, the longer duration group, and the late-onset group. SRMs for items regarding skilled hand activities, walking, and standing were relatively large. Our study indicates that the UMSARS (parts 2 and 4), SARA, and BBS are sensitive scales for evaluating MSA progression over 12 months. Items with large SRMs effectively evaluated short-term changes.

Latitude and HLA-DRB1 alleles independently affect the emergence of cerebrospinal fluid IgG abnormality in multiple sclerosis.

BACKGROUND: It is unclear whether the prevalence of oligoclonal IgG bands (OCBs) in multiple sclerosis (MS) is different between northern and southern regions of Asia. OBJECTIVE: This study aimed to compare the prevalence of OCBs and positive cerebrospinal fluid (CSF) findings between northern and southern regions of Japan and to investigate the association of these CSF findings with HLA-DRB1 alleles. METHODS: The study included 180 MS patients from Hokkaido (northern Japan) and 184 patients from Kyushu (southern Japan). The IgG index was defined as increased if it was >0.658. Presence of CSF OCBs and/or increased IgG index was defined as positive CSF findings. RESULTS: Positive CSF findings and OCB positivity were significantly higher in MS patients from Hokkaido than in those from Kyushu (p < 0.0001 for both). Logistic regression analysis revealed that after adjusting for covariates that can be related to abnormal CSF IgG production, the geographic region (Hokkaido) showed odds ratios (ORs) of 4.08 and 2.57, whereas the HLA-DRB1*04:05 allele showed ORs of 0.36 and 0.30 for positive CSF findings and OCB positivity, respectively. CONCLUSIONS: The results indicate that latitude and HLA-DRB1 alleles independently affect the emergence of CSF IgG abnormalities in Japanese patients with MS.

Open-label study to evaluate the pharmacodynamics, clinical efficacy, and safety of meropenem for adult bacterial meningitis in Japan.

The aim of this study was to assess the efficacy, safety, and concentration of meropenem in cerebrospinal fluid when meropenem (2 g every 8 h) was administered to Japanese adult patients with bacterial meningitis. Five Japanese patients (mean age 60.6 years [range 35-71]) were enrolled. Infection with Streptococcus pneumoniae (three patients), Streptococcus salivarius (one patient), and Staphylococcus aureus (one patient) was confirmed by cerebrospinal fluid culture. Meropenem (2 g every 8 h) was administered to all five patients. Treatment duration ranged from 14 to 28 days (mean 22.6 days). All the patients were successfully treated. The concentration of meropenem in cerebrospinal fluid ranged from 0.27 to 6.40 µg/ml up to 8.47 h and was over 1 µg/ml 3 h after starting meropenem infusion. In each patient, the present study confirmed for the first time that the concentration of meropenem in cerebrospinal fluid exceeded the minimal inhibitory concentration for these pathogens. Eleven clinical and laboratory adverse events considered to be related to meropenem were observed in all patients, but no serious adverse event and no discontinuance of treatment due to adverse events occurred. Thus meropenem appeared to be a well-tolerated and effective agent for Japanese adult patients with bacterial meningitis. 2 g every 8 h of meropenem was delivered to CSF and its concentration was exceed in MICs for the detected pathogens.

Apathy/depression, but not subjective fatigue, is related with cognitive dysfunction in patients with multiple sclerosis.

BACKGROUND: Cognitive impairment could affect quality of life for patients with multiple sclerosis (MS), and cognitive function may be correlated with several factors such as depression and fatigue. This study aimed to evaluate cognitive function in Japanese patients with MS and the association between cognitive function and apathy, fatigue, and depression. METHODS: The Brief Repeatable Battery of Neuropsychological tests (BRB-N) was performed in 184 Japanese patients with MS and 163 healthy controls matched for age, gender, and education. The Apathy Scale (AS), Fatigue Questionnaire (FQ), and Beck Depression Inventory Second Edition (BDI-II) were used to evaluate apathy, fatigue, and depression, respectively. Student's t-test was used to compare MS patients and healthy controls. Correlations between two factors were assessed using the Pearson correlation test, and multiple regression analysis was used to evaluate how much each factor affected the BRB-N score. RESULTS: In all BRB-N tests, patients with MS scored significantly lower than controls, and the effect size of symbol digit modalities test was the highest among the 9 tests of the BRB-N. Patients with MS had higher AS (p < 0.001), FQ (p < 0.0001), and BDI-II (p < 0.0001) scores than controls. In patients with MS, scores on most of the BRB-N tests correlated with scores on the AS and BDI-II; however, there was little correlation between scores on the BRB-N tests and those on the FQ. CONCLUSIONS: Cognitive function was impaired, particularly information-processing speed, and decreased cognitive function was correlated with apathy and depression in Japanese patients with MS. Despite the association between cognitive variables and depression/apathy, cognitive function was impaired beyond the effect of depression and apathy. However, subjective fatigue is not related with cognitive impairment. Taken together, this suggests that different therapeutic approaches are needed to improve subjective fatigue and cognition, and thereby quality of life, in patients with MS.

Novel GNE compound heterozygous mutations in a GNE myopathy patient.

INTRODUCTION: Molecular studies have revealed that some patients with myopathies with rimmed vacuoles have pathogenic mutations in the UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine kinase (GNE) and Z-band alternatively spliced PDZ motif-containing protein (ZASP) genes. METHODS: We investigated a patient with distal myopathy with rimmed vacuoles by muscle biopsy and sequenced 6 candidate genes. RESULTS: The patient carried GNE compound heterozygous missense mutations (p.V421A and p.N635K) and a ZASP variant (p.D673N). This patient also presented with distal weakness sparing the quadriceps muscles and had atypical results for Z-band-associated protein immunostaining. This finding indicates that the GNE mutations are pathogenic, and the diagnosis is compatible with GNE myopathy. CONCLUSIONS: By combining pathological studies and candidate gene screening, we identified a patient with GNE myopathy due to novel GNE compound heterozygous mutations.

Clinical features of spinal cord sarcoidosis: analysis of 17 neurosarcoidosis patients.

The diagnosis of neurosarcoidosis is often difficult; the imaging signs of spinal cord sarcoidosis sometimes mimic those of cervical spondylotic myelopathy, which is common in elderly persons. We examined the characteristics of spinal cord sarcoidosis in Japanese patients with neurosarcoidosis. This case series identified patients with neurosarcoidosis at four general hospitals and one university hospital from April 1998 to September 2010. All diagnoses were based on the diagnostic criteria proposed by Zajicek et al. Seventeen patients (nine men and eight women) were involved: six patients with spinal cord lesions accompanied by cervical spondylosis, five with cerebral lesions, three with cranial nerve lesions, two with meningitis, and one with nerve root lesions. Patients with spinal cord sarcoidosis had a higher onset age, longer duration from onset to diagnosis, reduced leukocytosis in the cerebrospinal fluid (CSF), and lower angiotensin-converting enzyme (ACE) levels in the CSF. The results of this study indicate that diagnosis of spinal cord sarcoidosis requires careful evaluation.

Vibrational and rotational structure and excited-state dynamics of pyrene.

Vibrational level structure in the S(0) (1)A(g) and S(1) (1)B(3u) states of pyrene was investigated through analysis of fluorescence excitation spectra and dispersed fluorescence spectra for single vibronic level excitation in a supersonic jet and through referring to the results of ab initio theoretical calculation. The vibrational energies are very similar in the both states. We found broad spectral feature in the dispersed fluorescence spectrum for single vibronic level excitation with an excess energy of 730 cm(-1). This indicates that intramolecular vibrational redistribution efficiently occurs at small amounts of excess energy in the S(1) (1)B(3u) state of pyrene. We have also observed a rotationally resolved ultrahigh-resolution spectrum of the 0(0) (0) band. Rotational constants have been determined and it has been shown that the pyrene molecule is planar in both the S(0) and S(1) states, and that its geometrical structure does not change significantly upon electronic excitation. Broadening of rotational lines with the magnetic field by the Zeeman splitting of M(J) levels was very small, indicating that intersystem crossing to the triplet state is minimal. The long fluorescence lifetime indicates that internal conversion to the S(0) state is also slow. We conclude that the similarity of pyrene's molecular structure and potential energy curve in its S(0) and S(1) states is the main cause of the slow radiationless transitions.

Rotationally resolved ultrahigh-resolution laser spectroscopy of the S2 (1)A1<--S0 (1)A1 transition of azulene.

We have observed rotationally resolved ultrahigh-resolution fluorescence excitation spectra of the 0(0)(0) (a-type) and 0(0)(0)+467 cm(-1) (b-type) bands of the S(2) (1)A(1)<--S(0) (1)A(1) transition of jet-cooled azulene. The observed linewidth is 0.0017 cm(-1), which corresponds to the lifetime of 3.1 ns in the S(2) state. Zeeman splitting of rotational lines is very small so that intersystem crossing to the triplet state is considered to be very slow. Inertial defect is very small and the molecule is considered to be planar in the S(0) and S(2) states (C(2v) symmetry). Rotational constants of the S(2) state are almost identical to those of the S(0) state, indicating that geometrical structure is similar in both electronic states. In this case, internal conversion (IC) by vibronic coupling is thought to be inactive. Therefore, the main radiationless transition process in the S(2) (1)A(1) state of azulene was identified to be IC to the S(1) (1)B(2) state. However, this S(2)-->S(1) IC is still slower than that of conventional polycyclic aromatic hydrocarbons. We consider it to be due to the shallower potential energy curve in the S(1) (1)B(2) state, which is also responsible for the extraordinarily fast S(1)-->S(0) IC in the isolated azulene molecule.