$zeta$-null geodesic gradient vector fields on a lorentzian para-sasakian manifold

Matsumoto, Koji,Mihai, Ion,Rosca, Radu Korean Mathematical Society 1995 대한수학회지 Vol.32 No.1

A Lorentzian para-Sasakian manifold M$(\varphi, \zeta, \eta, g)$ (abr. LPS-manifold) has been defined and studied in [9] and [10]. On the other hand, para-Sasakian (abr. PS)-manifolds are special semi-cosympletic manifolds (in the sense of [2]), that is, they are endowed with an almost cosympletic 2-form $\Omega$ such that $d^{2\eta}\Omega = \psi(d^\omega$ denotes the cohomological operator [6]), where the 3-form $\psi$ is the associated Lefebvre form of $\Omega$ ([8]). If $\eta$ is exact, $\psi$ is a $d^{2\eta}$-exact form, the manifold M is called an exact Ps-manifold. Clearly, any LPS-manifold is endowed with a semi-cosymplectic structure (abr. SC-structure).

ζ-NULL GEODESIC GRADIENT VECTOR FIELDS ON A LORENTZIAN PARA-SASAKIAN MANIFOLD

Koji Matsumoto,Ion Mihai,Radu Rosca 대한수학회 1995 대한수학회지 Vol.32 No.1

Development of a Test Method for Walking Trolleys with an Assist Function

Koji Matsumoto,Yoichi Asano,Hiroyuki Jinbo 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10

Walking trolleys that are currently being manufactured have a function that prevents downslope movement when the user crosses a slope. In this study, we have developed a test method to evaluate this function. First, we measured the handle-operating force exerted by elderly persons when crossing a slope by carrying out an experiment with 17 elderly participants. Analysis of the results indicated that the handle-operating force was 28 N. Based on these results, we developed a test method and a test equipment. Furthermore, we used the test equipment to conduct experiments on walking trolleys with and without activating the assist function to validate the test method. It was found that the proposed test can be performed with sufficient accuracy.

ON CR-SUBMANIFOLDS OF LOCALLY CONFORMAL KAHLER MANIFOLDS

MATSUMOTO, KOJI Korean Mathematical Society 1984 대한수학회지 Vol.21 No.1

ON CONFORMAL P-KILLING VECTOR FIELDS IN ALMOST PARACONTACT RIEMANNIAN MANIFOLDS

MATSUMOTO, KOJI Korean Mathematical Society 1981 대한수학회지 Vol.18 No.1

Effects of Oral Administration of Difructose Anhydride III on Selected Health and Blood Parameters of Group-housed Japanese Black Calves during the Preweaning Period

Matsumoto, Daisaku,Takagi, Mitsuhiro,Hasunuma, Hiroshi,Fushimi, Yasuo,Ohtani, Masayuki,Sato, Tadashi,Okamoto, Koji,Shahada, Francis,Tanaka, Tetsuya,Deguchi, Eisaburo Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.12

Two field studies were conducted to determine the efficacy of difructose anhydride III (DFA III) as a supplement in colostrum replacer (CR) for improving the general health status (judged on the basis of incidence of enteritis, bronchitis, and pneumonia) of group-housed suckling Japanese Black calves. In a preliminary study, CR supplemented with DFA III (6 g) was orally administered within 24 h of calving to eight individually reared calves fed colostrum (DFA III group) (Exp. 1). Subsequently, CR supplemented with DFA III (6 g) was orally administered twice within 2 and 12 h of calving to four calves (DFA III group) that were not fed colostrum (Exp. 2). In both experiments, the health status of the calves was assessed during the preweaning period. In Exp. 2, hematological and blood-chemistry parameters were analyzed 24 h after the second administration of CR and at 1 wk and 1 month after calving. The results were compared between the DFA III and control groups (without DFA III supplementation; Exp. 1: n = 10, Exp. 2: n = 4). In Exp. 1, the number of calves requiring medications for the treatment of enteritis, bronchitis, and pneumonia during the preweaning period was significantly (p<0.05) lower in the DFA III group than in the control group. In Exp. 2, supplementation of DFA III did not influence the gain in body weight of calves during the pre-weaning period. Calves in the DFA III group tended to require medications for a shorter duration than those in the control group (DFA III: 10.3 d/calf, control: 21.3 d/calf; p = 0.07). Significant differences (p<0.05) in the level of mean corpuscular hemoglobin, total protein, total cholesterol, and immunoglobulin (Ig)G were observed between the DFA III and control groups. These differences probably reflect the health and nutritional status of the calves. Additionally, the serum iron and lactoferrin concentrations at 24 h and 1 wk after calving, respectively, differed significantly between the 2 groups. These concentrations might reflect the incidence of infections after calving. The present study revealed that the administration of DFA III as a CR supplement may prevent diseases in group-housed calves during the pre-weaning period.

A Prediction Method of the Global Distribution Map of CO2 Column Abundance Retrieved from GOSAT Observation Derived from Ordinary Kriging

Mitsuhiro Tomosada,Koji Kanefuji,Yukio Matsumoto,Hiroe Tsubaki 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

We propose a method to generate a global distribution map of carbon dioxide (CO2) and methane (CH4)column abundance retrieved from spectra on irregular observation points by GOSAT (Greenhouse gases ObserbingSATellite). Global distribution map is gridded by 1 degree for latitude and longitude. Kriging in spatial statistics isapplied to the spatial data of CO2 and CH4 column abundance. We focus on CO2 density in this study, the distance anddifference of CO2 column abundances between observation points for sample pairs at each observation points overocean and over land on the earth’s surface are calculated. The relationship between the distance and the difference ofCO2 column abundances are represented by semi-variogram model. When semi-variogram is modeled, the difference ofsemi-variogram derived from the direction between observation points of sample pairs from North-pole direction isconsidered. And, we obtain the variogram model for each land cover. GOSAT was just launched, and CO2 columnabundance is not retrieved from spectra measured by GOSAT. Therefore, proposed method is applied to spatial data ofXCO2 instead of CO2 column abundance. We set the observation points on the earth’s surface based on the GOSATobservation plan. Global distribution map of XCO2 instead of CO2 column abundance is used, XCO2 value for eachobservation points are set. And we predict XCO2 values on the grid in global distribution map from the set observationpoints and XCO2. As a result, the standard deviation of prediction error (predicted value ? actual value) is 0.324. Thisstandard deviation, which is 0.1% of XCO2 value, is enough small comparison with target accuracy (1%).

Posttreatment human papillomavirus testing for residual or recurrent high-grade cervical intraepithelial neoplasia: a pooled analysis

Mamiko Onuki,Koji Matsumoto,Manabu Sakurai,Hiroyuki Ochi,Takeo Minaguchi,Toyomi Satoh,Hiroyuki Yoshikawa 대한부인종양학회 2016 Journal of Gynecologic Oncology Vol.27 No.1

Objective: We conducted a pooled analysis of published studies to compare the performance of human papillomavirus (HPV) testing and cytology in detecting residual or recurrent diseases after treatment for cervical intraepithelial neoplasia grade 2 or 3 (CIN 2/3). Methods: Source articles presenting data on posttreatment HPV testing were identified from the National Library of Medicine (PubMed) database. We included 5,319 cases from 33 articles published between 1996 and 2013. Results: The pooled sensitivity of high-risk HPV testing (0.92; 95% confidence interval [CI], 0.90 to 0.94) for detecting posttreatment CIN 2 or worse (CIN 2+) was much higher than that of cytology (0.76; 95% CI, 0.71 to 0.80). Co-testing of HPV testing and cytology maximized the sensitivity (0.93; 95% CI, 0.87 to 0.96), while HPV genotyping (detection of the same genotype between pre- and posttreatments) did not improve the sensitivity (0.89; 95% CI, 0.82 to 0.94) compared with high-risk HPV testing alone. The specificity of high-risk HPV testing (0.83; 95% CI, 0.82 to 0.84) was similar to that of cytology (0.85; 95% CI, 0.84 to 0.87) and HPV genotyping (0.83; 95% CI, 0.81 to 0.85), while co-testing had reduced specificity (0.76; 95% CI, 0.75 to 0.78). For women with positive surgical margins, high-risk HPV testing provided remarkable risk discrimination between test-positives and test-negatives (absolute risk of residual CIN 2+ 74.4% [95% CI, 64.0 to 82.6] vs. 0.8% [95% CI, 0.15 to 4.6]; p<0.001). Conclusion: Our findings recommend the addition of high-risk HPV testing, either alone or in conjunction with cytology, to posttreatment surveillance strategies. HPV testing can identify populations at greatest risk of posttreatment CIN 2+ lesions, especially among women with positive section margins.

Response to Assist Torque Failure of Physical-Assistant Robots

Yoichi Asano,Koji Matsumoto,Hiroyuki Jinbo 제어로봇시스템학회 2017 제어로봇시스템학회 국제학술대회 논문집 Vol.2017 No.10

In physical assistant robots used to mitigate burden on the lumbar, there is a risk that if the assist torque is lost, excessive burden may be applied to the lumbar. Therefore, for some products, a system to lock the moving parts on the lumbar is examined as a prevention measure against this risk. Through an experiment on a subject who wears test equipment that simulates a physical-assistant robot, the myogenic potential at the lumbar when the assist torque was lost was measured. Results indicated that if the moving part is locked within 151 msec after the loss of assist torque, the load of the lifted baggage can be supported by the frame of the robot and thus the burden on the user can be mitigated.

Lifestyle and body composition changes in patients with rheumatoid arthritis during the COVID-19 pandemic: A retrospective, observational study

Masahiro Tada,Yutaro Yamada,Koji Mandai,Yoshinari Matsumoto,Noriaki Hidaka 대한골다공증학회 2023 Osteoporosis and Sarcopenia Vol.9 No.1

Objectives: Behavioral restrictions and staying at home during the COVID-19 pandemic have affected lifestyles. It was hypothesized that patients with rheumatoid arthritis (RA) decreased their activities of daily living (ADL) and exercise during the pandemic. The aim of this study is to investigate the changes in lifestyle and body composition. Methods: Data were obtained from an observational study (CHIKARA study). Of 100 RA patients, 70 (57 women, 13 men) were followed-up with measurements of grip strength, as well as muscle mass, fat mass, and basal metabolic rate by a body composition analyzer. Changes in ADL and exercise were evaluated using a visual analog scale. The relationships between changes in ADL or exercise and body composition were investigated. Results: Muscle mass and grip strength were significantly lower after behavioral restrictions compared to the periods before restrictions (34.0 vs 34.7 kg, P < 0.001; 16.2 vs 17.2 kg, P = 0.013, respectively). Fat mass was significantly greater after behavioral restrictions compared to the periods before restrictions (16.2 vs 15.5 kg, P = 0.014). The mean decrease in ADL was 44%, whereas that of exercise was 20%. The change in muscle mass (β = -0.335, P = 0.007) was the only independent factor for the change in exercise on multivariate analysis. Conclusions: Muscle mass and grip strength decreased and fat mass increased in RA patients with the behavioral restrictions of the COVID-19 pandemic. Muscle mass decreased in patients without exercise. Maintenance of muscle mass may be important during the COVID-19 pandemic.