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Kei Takasawa,1 Hiroyo Mabe,2 Fusa Nagamatsu,2 Naoko Amano,3 Yuichi Miyakawa,4 Akito Sutani,4 Reiko Kagawa,5 Satoshi Okada,5 Yusuke Tanahashi,6 Shigeru Suzuki,6 Shota Hiroshima,7 Keisuke Nagasaki,7 Sumito Dateki,8 Shigeru Takishima,9 Ikuko Takahashi,10 Kenichi Kashimada1 1Department of Pediatrics and Developmental Biology, Tokyo Medical and Dental University (TMDU), Tokyo, Japan; 2Department of Pediatrics, Kumamoto University Hospital, Kumamoto, Japan; 3Department of Pediatrics, Saitama City Hospital, Saitama, Japan; 4Department of Pediatrics, Kawaguchi Municipal Medical Center, Saitama, Japan; 5Department of Pediatrics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan; 6Department of Pediatrics, Asahikawa Medical University, Asahikawa, Japan; 7Division of Pediatrics, Department of Homeostatic Regulation and Development, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; 8Department of Pediatrics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan; 9Department of Pediatrics, Soka Municipal Hospital, Saitama, Japan; 10Department of Pediatrics, Akita University Graduate School of Medicine, Akita, JapanCorrespondence: Kei Takasawa, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan, Tel +81-3-5803-5246, Fax +81-3-5803-5249, Email ktakasawa.ped@tmd.ac.jpIntroduction: Although the treatment success of long-term growth hormone therapy (GHT) is dependent on maintaining patients’ adherence to treatment, marked variations in adherence levels among children with GHT (eg, 7– 71% nonadherence) have been reported. Barriers to or promoters of GHT adherence have been discussed and investigated, and digital health technologies, such as electronic GH injection devices, may have the potential to assess adherence to GHT more accurately. Thus, we conducted a multicenter, retrospective cohort study using GH injection log analysis of an electronic GH device, GROWJECTOR®L, to qualify adherence and explore the factors influencing adherence.Methods: This study enrolled 41 patients (median[range] age, 5.8[3.0 ~ 17.0] years) with short stature from nine Japanese medical institutions. The injection log data (12– 48 weeks) were read by smartphones and collected into the data center through a cloud server.Results: Although cumulative adherence rates remained higher than 95% throughout the observation period, five (12.2%) patients had low adherence (< 85%). Subsequently, subgroup and logistic regression analyses for exploring factors affecting adherence revealed that self-selection of GH device and irregular injection schedule (ie, frequent injections after midnight) significantly affected adherence rate (p=0.034 and 0.048, respectively). In addition, higher rates of irregular injections significantly affected low adherence (median[range], 11.26[0.79 ~ 30.50]% vs 0.26[0.00 ~ 33.33]%, p = 0.029).Discussion: Our study indicated that injection log analysis using an electronic GH device could detect irregular injection schedules due to a night owl or disturbance in lifetime rhythm affecting low adherence and had significant potential to encourage collaborative monitoring of adherence with healthcare providers and patients themselves/caregivers, along with growing autonomy and shared decision-making. Our study suggests the significance of narrative and personal approaches to adherence of patients with GHT and the usefulness of digital devices for such an approach and for removing various barriers to patient autonomy, leading to improvement and maintenance of adherence.Keywords: GH therapy, digital health technology, shared decision- making, patient autonomy

We report the growth of bulk β-Ga2O3 crystals based on crystal pulling from a melt using a cold container without employing a precious-metal crucible. Our approach, named oxide crystal growth from cold crucible (OCCC), is a fusion between the skull-melting and Czochralski methods. The absence of an expensive precious-metal crucible makes this a cost-effective crystal growth method, which is a critical factor in the semiconductor industry. An original construction 0.4–0.5 MHz SiC MOSFET transistor generator with power up to 35 kW was used to successfully grow bulk β-Ga2O3 crystals with diameters up to 46 mm. Also, an original diameter control system by generator frequency change was applied. In this preliminary study, the full width at half maximum of the X-ray rocking curve from the obtained β-Ga2O3 crystals with diameters ≤ 46 mm was comparable to those of β-Ga2O3 produced by edge-defined film fed growth. Moreover, as expected, the purity of the obtained crystals was high because only raw material-derived impurities were detected, and contamination from the process, such as insulation and noble metals, was below the detection limit. Our results indicate that the OCCC technique can be used to produce high-purity bulk β-Ga2O3 single crystalline substrate. [ABSTRACT FROM AUTHOR]

Norio Sugawara,1,2 Ayako Kaneda,2 Ippei Takahashi,3 Shigeyuki Nakaji,3 Norio Yasui-Furukori2 1Department of Clinical Epidemiology, Translational Medical Center, National Center of Neurology and Psychiatry, Kodaira, Tokyo, 2Department of Neuropsychiatry, Hirosaki University School of Medicine, Hirosaki, 3Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan Background: Efficient screening for depression is important in community mental health. In this study, we applied a stratum-specific likelihood ratio (SSLR) analysis, which is independent of the prevalence of the target disease, to screen for depression among community-dwelling individuals.Method: The Center for Epidemiologic Studies Depression Scale (CES-D) and the Mini International Neuropsychiatric Interview (MINI) were administered to 789 individuals (19–87 years of age) who participated in the Iwaki Health Promotion Project 2011. Major depressive disorder (MDD) was assessed using the MINI.Results: For MDD, the SSLRs were 0.13 (95% CI 0.04–0.40), 3.68 (95% CI 1.37–9.89), and 24.77 (95% CI 14.97–40.98) for CES–D scores of 0–16, 17–20, and above 21, respectively.Conclusion: The validity of the CES-D is confirmed, and SSLR analysis is recommended for its practical value for the detection of individuals with the risk of MDD in the Japanese community. Keywords: screening, depression, Center for Epidemiologic Studies Depression Scale, stratum-specific likelihood ratio

Akinari Inui,1 Ippei Takahashi,2 Sizuka Kurauchi,2 Yuki Soma,2 Toshiaki Oyama,1 Yoshihiro Tamura,1 Takao Noguchi,1 Kouichi Murashita,3 Shigeyuki Nakaji,2 Wataru Kobayashi1 1Department of Oral and Maxillofacial Surgery, 2Department of Social Medicine, 3COI Research Initiatives Organization, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori Prefecture, Japan Purpose: Prevention, early detection and effective rehabilitation of dysphagia are important issues to be considered in an aging society. Previous studies have shown conflicting findings regarding the association between dysphagia and its potential risk factors, including age, malnutrition, oral conditions, lifestyle and medical history. Herein, we assessed the prevalence and association of dysphagia with potential risk factors in 50- to 79-year-old adults dwelling in a community in Japan. Patients and methods: In this study, there were 532 participants (185 males and 347 females). Participants who responded positively to the question “Do you sometimes choke on drinks/food such as tea and soup?” or those who presented with abnormal repetitive saliva swallowing test findings were diagnosed with dysphagia. The data collected from these participants included the following: number of teeth, occurrence of oral dryness, age, body mass index, serum albumin concentration, smoking, drinking and exercise habits, presence of diseases, such as diabetes mellitus and hypertension, and questions from the Mini–Mental State Examination. Results: Dysphagia was observed in 33 males (17.8%) and 76 females (21.9%). To explore the effect of the potential risk factors on the prevalence of dysphagia, a model was built by multivariate logistic regression analysis. Using the forced entry method, oral dryness (odds ratio [OR] =3.683 and P=0.003 in males; OR =1.797 and P=0.032 in females) and the number of teeth (OR =0.946 and P=0.038 in males) were found to be significantly related to dysphagia. Conclusion: This cross-sectional study demonstrated associations between oral conditions and dysphagia. Factors such as oral dryness and number of teeth may contribute to dysphagia more so than aging, lifestyle and comorbidity in community-dwelling adults over the age of 50. Keywords: oral dryness, number of teeth, swallow, nutrition, lifestyle

Tetsu Tomita,1 Norio Yasui-Furukori,1 Norio Sugawara,1,2 Kohei Ogasawara,3 Koki Katagai,3 Hisao Saito,4 Kaori Sawada,5 Ippei Takahashi,5 Kazuhiko Nakamura1 1Department of Neuropsychiatry, Graduate School of Medicine, Hirosaki University, Hirosaki, Japan; 2Aomori Prefectural Center for Mental Health and Welfare, Aomori, Japan; 3School of Medicine, Hirosaki University, Hirosaki, Japan; 4Department of Urology, Oyokyo Kidney Research Institute, Hirosaki, Japan; 5Department of Social Medicine, Graduate School of Medicine, Hirosaki University, Hirosaki, Japan Background: We investigated the prevalence of depression in hemodialysis (HD) patients using the Center for Epidemiologic Studies for Depression (CES-D) scale and the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (SCID) and compared the rates with those of community dwelling people in Japan.Patients and methods: A total of 99 patients undergoing HD were recruited. Blood sampling was performed no later than 2 weeks prior to assessment. As a reference group for SCID and CES-D evaluation, 404 age- and sex-matched healthy controls who had participated in the Iwaki Health Promotion Project were included in this study. The SCID and the CES-D scale were administered to all participants to diagnose their depression. Participants who met the criteria of a major depressive episode according to the SCID were classified as SCID depression and the participants whose CES-D score was 16 or higher were classified as CES-D depression.Results: Ninety-nine HD patients completed the evaluation and data collection. There were no significant differences in age, sex, or CES-D scores between HD patients and controls. There were 12 cases of SCID depression in HD patients and four cases in controls. There was a significant difference between HD patients and controls in the prevalence of SCID depression. There were no significant differences between the two groups with regard to demographic or clinical data. There were 19 HD patients and 24 controls who showed CES-D depression. There was no significant difference between HD patients and controls in the prevalence of CES-D depression. There was a significant difference in potassium level between the two groups, but there were no significant differences in any of the other items.Conclusion: There were significantly more HD patients showing SCID depression than controls in the present study. In clinical settings, the SCID might be useful in surveying cases of depression detected by screening tools among HD patients. Keywords: depression, Center for Epidemiologic Studies for Depression, Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnosis

Akinari Inui,1 Ippei Takahashi,2 Kaori Sawada,2 Akimoto Naoki,2 Toshirou Oyama,1 Yoshihiro Tamura,1 Toshiyuki Osanai,1 Anna Satake,1 Shigeyuki Nakaji,2 Wataru Kobayashi1 1Department of Oral and Maxillofacial Surgery, Hirosaki University Graduate School of Medicine, 2Department of Social Medicine, Hirosaki University Graduate School of Medicine, Hirosaki City, Aomori Prefecture, Japan Purpose: Decline in the number of teeth and physical fitness begins from 40 years of age; however, several epidemiological studies have identified relationships between oral conditions and physical performance parameters in community-dwelling elderly population. The aim of this study was to validate the relationship between the muscle mass and its function and oral conditions (number of teeth and dental occlusion) after 40 years of age in a community-dwelling population in Japan.Materials and methods: The subjects comprised of 552 volunteers (198 males and 354 females, 40–79 years) who participated in the Iwaki Health Promotion Project in 2013. Multiple linear regression analyses were performed with the measures of the muscle mass and its function as objective variables and the measures of the number of teeth, age, body mass index, medical history, serum albumin concentration, smoking status, habitual alcohol intake, marital status, education levels, and exercising habits as explanatory variables. The relationships between the Eichner index and the muscle mass and its function were analyzed using analysis of covariance, with adjustment for confounding factors.Results: After adjusting for confounding factors, the number of teeth was shown to be an independent risk factor for the timed 10 m walk test (in females) and the skeletal muscle mass of the whole body (in males). The results also revealed that the timed 10 m walk test was significantly correlated with the Eichner index (Classes A and C in females were correlated).Conclusion: This cross-sectional study on a Japanese community-dwelling population revealed relationships between oral conditions and the muscle mass and its function. However, the interpretation of our results was hampered by a lack of data, including those on socioeconomic status and longitudinal observations. Future research exploring teeth loss and the muscle mass and its function is warranted. Keywords: number of teeth, sarcopenia, timed 10 m walk test, hand grip strength, skeletal muscle mass

Kazutoshi Kubo,1 Norio Sugawara,1,2 Ayako Kaneda,1 Ippei Takahashi,3 Kazuhiko Nakamura,1 Shigeyuki Nakaji,3 Norio Yasui-Furukori1 1Department of Neuropsychiatry, Hirosaki University School of Medicine, Hirosaki, 2Department of Psychiatry, Aomori Prefectural Center for Mental Health and Welfare, Aomori, 3Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan Objectives: Restless legs syndrome (RLS) is a sensorimotor disturbance that causes the production of impulses and dysesthesia and makes the patients feel as though they must move their lower extremities. Because the symptoms of RLS in the lower limbs tend to develop at night, RLS could cause sleep disorders. We investigated an association between the symptoms of RLS and the health-related quality of life among community-dwelling individuals in Japan. Methods: In this cross-sectional survey, we enrolled 985 volunteers who participated in the Iwaki Health Promotion Project in 2013. The symptoms of RLS were evaluated by the criteria of the International Restless Legs Syndrome Study Group. The assessments included an interview to obtain sociodemographic data, the second version of the Short Form Health Survey, the Center for Epidemiological Studies Depression scale, and the Pittsburgh Sleep Quality Index. A multiple regression analysis was used to assess the relationship between the symptoms of RLS and subscores of the Short Form Health Survey, Version 2. Results: The overall prevalence of RLS in our participants was 1.0%. We found a significant and negative association between symptoms of RLS and physical functioning, role – physical functioning, bodily pain, social functioning, and the physical composite summary score. Conclusion: After adjusting for confounders such as age, sex, and comorbidity, the burden of RLS appears to be mainly a physical problem. Impaired health-related quality of life among community individuals with RLS emphasizes the importance of screening for these symptoms and evaluating the need for treatment. Keywords: cross-sectional study, restless legs syndrome, quality of life, Japanese

Tetsu Tomita,1 Norio Yasui-Furukori,1 Norio Sugawara,1,2 Ippei Takahashi,3 Kaori Sawada,3 Kazuhiko Nakamura11Department of Neuropsychiatry, Graduate School of Medicine, Hirosaki University, Hirosaki, 2Aomori Prefectural Center for Mental Health and Welfare, Aomori, 3Department of Social Medicine, Graduate School of Medicine, Hirosaki University, Hirosaki, JapanBackground: We aimed to discriminate individuals with depressive state from individuals with cognitive impairment among community-dwelling people using the subjective memory complaints (SMC) scale.Methods: The study group consisted of 289 volunteers (over 60 years old; 104 males and 185 females). Participants’ SMCs were assessed using the SMC scale. The Japanese version of the Center for Epidemiologic Studies for Depression scale and the Mini-Mental State Examination were administered. Participants whose Center for Epidemiologic Studies for Depression scores were 16 or higher were defined as the depressive group and participants whose Mini-Mental State Examination scores were less than 24 were defined as the cognitive impairment group. Exploratory factor analysis was performed to identify the factor structure of the items of the SMC scale. A multiple logistic regression analysis of the association between depressive state and cognitive impairment and the score of each factor was performed.Results: In the final factor analysis model, six items of the SMC scale remained, and a two-factor structure was adequate. Factor 1 included the items 8, 9, and 10 about thought or the ability to think; thus, Factor 1 was defined as “thought disturbance factor”. Factor 2 included the items 1, 2, and 4 about memory or forgetfulness; thus, Factor 2 was defined as “memory disturbance factor”. In the multiple logistic regression analysis, Factor 1 was significantly associated with depressive state and Factor 2 was significantly associated with cognitive impairment.Conclusion: For individuals with SMCs, we might be able to discriminate depressive state or depression from cognitive impairment or dementia through a detailed investigation using the SMC scale.Keywords: geriatric psychiatry, affective disorders, primary care

Koji Tsuruga,1 Norio Sugawara,1 Yasushi Sato,1 Manabu Saito,1 Hanako Furukori,2 Taku Nakagami,3 Kazuhiko Nakamura,1 Ippei Takahashi,4 Shigeyuki Nakaji,4 Norio Yasui-Furukori1 1Department of Neuropsychiatry, Hirosaki University School of Medicine, Hirosaki, Japan; 2Department of Psychiatry, Kuroishi-Akebono Hospital, Kuroishi, Japan; 3Department of Neuropsychiatry, Odate Municipal General Hospital, Odate, Japan; 4Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan Background: It has been reported that the onset of schizophrenia and the physical complications after its onset are related to diet. Diet has been considered as a variable factor of the pathogenesis of schizophrenia. However, the results of studies on this relationship have been inconsistent. Nutrients are consumed as a mixture in the diet. It is difficult to study them in isolation because they may have mutually complementary effects. The aim of this study was to assess the association between dietary patterns and schizophrenia in Japan.Methods: The subjects comprised 237 outpatients aged 30–60 years (123 males and 114 females) with diagnoses of either schizophrenia or schizoaffective disorder. The patient diagnoses were determined based on medical records. Patients were recruited between June 2011 and August 2011. As a reference group, 404 healthy volunteers aged 30–60 years (158 males and 246 females) were also included. Demographic data (age, sex, and level of education) were collected by face-to-face method interviews and self-administered questionnaires. We assessed eating habits over the last month using a validated brief self-administered diet history questionnaire. We detected dietary patterns through a principal component analysis of calorie-adjusted intake; two principal components were retained. The principal components for each dietary pattern and for each individual were divided into tertiles by principal component scores. Results: We derived two dietary patterns by principal component analysis; namely, the “vegetable” dietary pattern and the “cereal” dietary pattern. In the “cereal” dietary pattern, the high tertile was associated with a significantly increased risk of schizophrenia (P

Masamichi Ishioka,1 Norio Sugawara,1 Ayako Kaneda,1 Noriyuki Okubo,2 Kaori Iwane,2 Ippei Takahashi,2 Norio Yasui-Furukori1 1Department of Neuropsychiatry, 2Department of Social Medicine, Graduate School of Medicine, Hirosaki University, Hirosaki, JapanIntroduction: Screening tools for dementia should be valid and easy to complete and have a low psychological burden. Consistent with these principles, the Yamaguchi fox/pigeon-imitation test (YFPIT) has been developed. However, there is little information on the utility of the YFPIT for preclinical populations, although the detection of proven prodromal and preclinical states is important.Materials and methods: We recruited 392 volunteers who were at least 60 years old (139 men and 253 women) and had participated in the Iwaki Health Promotion Project. The YFPIT was administered to all participants.Results: Most subjects succeeded in imitating the fox gesture regardless of their cognitive function impairment, while the success rates for the pigeon gesture were 75.3% in the normal group and 56.3% in the cognitive impairment group. The sensitivity, specificity, positive predictive value (PV+), and negative predictive value (PV-) were 43.8%, 75.3%, 7.0%, and 97.0%, respectively. The greatest significant difference between the imitation of the pigeon gesture and cognitive impairment was found in females with subjective memory impairments (P=0.001). In that group, the sensitivity, specificity, PV+, and PV- were 100%, 81.9%, 18.8%, and 100%, respectively.Conclusion: This study suggests that the utility of the YFPIT is limited in the general population, but that it is a useful tool in females with subjective memory impairments in a community-dwelling population.Keywords: dementia, gesture imitation, brief screening

Koji Tsuruga,1 Norio Sugawara,1 Norio Yasui-Furukori,1 Ippei Takahashi,2 Shoko Tsuchimine,1 Ayako Kaneda,1 Shigeyuki Nakaji,2 Kazuhiko Nakamura1 1Department of Neuropsychiatry, 2Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan Background: Amyloid beta (Aβ) levels have been associated with an increased risk of Alzheimer’s disease (AD). As depression is common before the onset of AD, serum Aß levels could be associated with depressive symptoms. The aim of this study was to investigate whether serum Aβ levels are associated with depressive symptoms and/or cognitive function in community-dwelling elderly individuals. Methods: We examined the association between serum Aβ levels and depression among 419 Japanese community-dwelling elderly individuals aged 60 years and over. Subjects were divided into two subgroups: younger elderly between 60 and 69 years old and older elderly over 69 years old. The Mini-Mental State Examination (MMSE) was used to assess cognitive function, and symptoms of depression were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D). The ability to perform activities of daily living was evaluated using the Tokyo Metropolitan Institute of Gerontology Index of Competence. Serum Aβ levels were measured with a human amyloid beta enzyme-linked immunosorbent assay kit. Results: After controlling for potential confounding variables, a multiple linear regression analysis showed that increased levels of serum Aβ40 and Aβ42 were associated with higher CES-D scores in the older elderly subgroup. Under the same condition, multiple regression showed that serum Aβ levels were not associated with MMSE scores among the total subjects, younger elderly, or older elderly. Conclusion: Serum Aβ levels were associated with depressive symptoms in community-dwelling elderly individuals. The present study indicates the possibility that serum Aβ may be involved in the development of late-onset depression. Keywords: Alzheimer’s disease, depression, dementia, Japanese

The CALorimetric Electron Telescope (CALET) space experiment, which has been developed by Japan in collaboration with Italy and the United States, is a high-energy astroparticle physics mission on the International Space Station (ISS). The primary goals of the CALET mission include investigation of possible nearby sources of high-energy electrons, detailed study of galactic cosmic-ray acceleration and propagation, and search for dark matter signatures. With a long-term observation onboard the ISS, the CALET experiment measures the flux of cosmic-ray electrons (including positrons) up to 20 TeV, gamma-rays to 10 TeV, and nuclei up to 1,000 TeV based on its charge separation capability from Z = 1 to 40. Since the start of science operation in mid-October, 2015, a continuous observation has been maintained without any major interruptions. The number of triggered events over 10 GeV is nearly 20 million per month. By using the data obtained during the first two-years, here we present a summary of the CALET observations: 1) Electron+positron energy spectrum, 2) Nuclei analysis, 3) Gamma-ray observation with a characterization of the on-orbit performance. The search results for the electromagnetic counterparts of LIGO/Virgo gravitational wave events are also discussed.

Ikuno Takahashi,1,3 Kyoji Furukawa,2 Waka Ohishi,1 Tetsuya Takahashi,3 Masayasu Matsumoto,3 Saeko Fujiwara11Department of Clinical Studies, 2Department of Statistics, Radiation Effects Research Foundation (RERF), Hiroshima, Japan; 3Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Hiroshima, JapanAbstract: Peripheral arterial disease (PAD) generally remains under-recognized, mainly due to the specialized technical skills required to detect the low values of the ankle-brachial index (ABI). As a simpler and faster alternative to the standard method using continuous-wave Doppler ultrasound, we evaluated automated oscillometric ABI measurement by VP-2000 with an elderly cohort of 113 subjects (age range, 61 to 88 years). The standard deviation in ABIs measured by the Doppler method was statistically greater than that measured by the oscillometric method for each of the two legs (P < 0.001). Correlations in ABIs between the two methods were 0.46 for the left leg and 0.61 for the right leg; this result appears to have been caused by interobserver variation in the Doppler ABI measurements. While the trend showing greater differences between average oscillometric- and Doppler-ABIs was significant at the lower ABI ranges, there was little indication of differences in measurements having an average ABI > 1.1. The difference between the methods was suggestively larger in subjects who were smokers than in non-smokers (P = 0.09), but the difference was not affected by other potential atherosclerotic risk factors, including age at examination (P > 0.50). A larger difference at lower ABIs led to better PAD detection by the Doppler method compared to the oscillometric method (sensitivity = 50%, specificity = 100%), although the overall agreement was not small (Cohen's Kappa = 0.65). Our findings indicate that oscillometric devices can provide more accurate estimation of the prevalence of PAD in elderly individuals than the conventional Doppler method.Keywords: ankle-brachial index, oscillometry, Doppler, peripheral arterial disease

A high pressure required to drive the liquid can be generated by the compact electrohydrodynamic (EHD) pumps with multiple pairs of the rod-to-rod and meshy parallel plates electrode assemblies arranged in series. In this work, the performance of EHD pumps with electrodes up to nine pairs has been examined as a function of the applied voltage using a semi-insulating liquid. The pressure generated by energized electrodes gives rise to the vigorous liquid flow and the liquid ejects from the pump outlet. The flow direction always is from the cathode toward the anode. The pressure increases with nearly the square of the applied voltage and in proportion to the number of electrode pairs. The maximum pressure head achieved with a series of nine electrode pairs is 25.3 kPa at 18 kV with maximum power consumption of 7.2 W. The generated pressure is maintained stably at constant level of the corresponding value. EHD pumping is attributed to conduction pumping based on an unbalance of heterocharges with single ionic polarity in the vicinity of the anode and cathode. Index Terms--EHD pump, conduction pumping, semi-insulating liquid, pressure head, dc voltage, potential distribution, flow rate.