著者

Michihito TAGAWA Chihiro KURASHIMA Genya SHIMBO Hiroshi OMURA Kenji KOYAMA Noriyuki HORIUCHI Yoshiyasu KOBAYASHI Keiko KAWAMOTO Kazuro MIYAHARA

出版者

公益社団法人 日本獣医学会

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.17-0051, (Released:2017-05-05)

被引用文献数

4

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A three-year-old spayed domestic short-haired cat presented for evaluation of weight loss, cardiomegaly and pleural effusion. Echocardiographic examination demonstrated a thickened pericardium with mild pericardial effusion and a large volume of pleural effusion characterized by exudate. Although the cat was treated with antibiotics, the clinical symptoms did not improve. The cat developed dyspnea and died on day 7. Necropsy revealed a large amount of modified transudates ascites, pleural effusion and markedly dilated pericardium. Histopathological examination revealed severe exudation of fibrin and granulation tissue in a thick layer of the epicardium. The cat was diagnosed with fibrinous pericarditis secondary to bacterial infection.

著者

Hiroshi Kajihara

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.25, no.2, pp.251-273, 2020-10-28 (Released:2020-10-28)

参考文献数

45

被引用文献数

2

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Three species of nemerteans, Balionemertes cf. australiensis Sundberg, Gibson, and Olsson, 2003 (Palaeonemertea), Prosadenoporus olympiae sp. nov. (Hoplonemertea: Eumonostilifera), and Coella gloriae sp. nov. (Hoplonemertea: Polystilifera: Reptantia), are reported based on material collected intertidally at a rocky shore in Cebu Island, Republic of the Philippines. Cytochrome c oxidase subunit I (COI) barcode sequences of these species have earlier been published elsewhere. The Cebu specimen that is herein identified tentatively as Balionemertes cf. australiensis posseses i) small black dots on the ventral body surface, ii) a neurochord in the lateral nerve, iii) serial rhynchocoelic septa, and iv) nephrostomes, characters that were not mentioned in the original description of the species from Australia; the exact species identification requires barcode sequences from topotypes. Prosadenoporus olympiae can be differentiated morphologically from other congeners by having three accessory-stylet pouches; when alive, worms of this species showed negative hydrotaxis. Coella gloriae differs from all the reptantic polystiliferans by having i) four rows of the eyes, ii) the cephalic furrows, iii) no dorsal marking, iv) separate mouth and proboscis openings, v) blind-ending extracerebral vessels, vi) non-forked fibre core in the dorsal ganglia, vii) the subdorsal nerves, and viii) the cerebral organs partly overlapping the brain.

著者

Hiroki TAMARU Yuki SAITO Shinnosuke TAKAMICHI Tomoki KORIYAMA Hiroshi SARUWATARI

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Transactions on Information and Systems (ISSN:09168532)

巻号頁・発行日

vol.E103.D, no.3, pp.639-647, 2020-03-01 (Released:2020-03-01)

参考文献数

32

被引用文献数

3

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This paper proposes a generative moment matching network (GMMN)-based post-filtering method for providing inter-utterance pitch variation to singing voices and discusses its application to our developed mixing method called neural double-tracking (NDT). When a human singer sings and records the same song twice, there is a difference between the two recordings. The difference, which is called inter-utterance variation, enriches the performer's musical expression and the audience's experience. For example, it makes every concert special because it never recurs in exactly the same manner. Inter-utterance variation enables a mixing method called double-tracking (DT). With DT, the same phrase is recorded twice, then the two recordings are mixed to give richness to singing voices. However, in synthesized singing voices, which are commonly used to create music, there is no inter-utterance variation because the synthesis process is deterministic. There is also no inter-utterance variation when only one voice is recorded. Although there is a signal processing-based method called artificial DT (ADT) to layer singing voices, the signal processing results in unnatural sound artifacts. To solve these problems, we propose a post-filtering method for randomly modulating synthesized or natural singing voices as if the singer sang again. The post-filter built with our method models the inter-utterance pitch variation of human singing voices using a conditional GMMN. Evaluation results indicate that 1) the proposed method provides perceptible and natural inter-utterance variation to synthesized singing voices and that 2) our NDT exhibits higher double-trackedness than ADT when applied to both synthesized and natural singing voices.

著者

Rimpei Kamamoto Kenji Suzuki Tetsuya Kawano Hiroshi Hanado Katsuhiro Nakagawa Yuki Kaneko

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

vol.16, pp.115-119, 2020 (Released:2020-07-04)

参考文献数

12

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Two products from the Global Precipitation Measurement (GPM) Dual-frequency Precipitation Radar (DPR) algorithms, a flag of intense solid precipitation above the −10°C height (“flagHeavyIcePrecip”) and a classification of precipitation type (“typePrecip”) were validated by ground-based hydrometeor measurements and X-band multi-parameter (X-MP) radar observations of snow clouds on 4 February 2018. Contoured frequency by altitude diagrams of the X-MP radar reflectivity exhibited a significant difference between footprints flagged and unflagged by the “flagHeavyIcePrecip” algorithm, which indicated that the algorithm is reasonable. The hydrometeor classification (HC) by the X-MP radar, which was confirmed by microphysical evidence from ground-based hydrometeor measurements, suggested the existence of graupel in the footprints with “flagHeavyIcePrecip”. In addition, according to the information of the GPM DPR, the “flagHeavyIcePrecip” footprints were characterized by not only graupel but also large snowflakes. According to the information of X-MP radar HC, the “typePrecip” algorithm by the detection of “flagHeavyIcePrecip” was effective in classifying precipitation types of snow clouds, whereas it seems that there is room for improvement in the “typePrecip” algorithms based on the extended-DPRm-method and H-method.

著者

Hiroshi Imamura Yukio Sekiguchi Tomomi Iwashita Hiroshi Dohgomori Katsunori Mochizuki Kazunori Aizawa Shin-ichi Aso Yuichi Kamiyoshi Uichi Ikeda Jun Amano Kazufumi Okamoto

出版者

The Japanese Circulation Society

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

vol.75, no.1, pp.59-66, 2011 (Released:2010-12-24)

参考文献数

37

被引用文献数

45 66 29

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Background: Acute aortic dissection (AAD) classically presents as sudden, severe chest, back, or abdominal pain. However, there have been several documented cases presenting with atypical features. The clinical characteristics and outcomes of patients with painless AAD were investigated. Methods and Results: The study group comprised 98 patients (53 males, 45 females; 66±12 years) with AAD admitted to hospital from 2002 to 2007: 16 patients (17%) had no pain (Painless group) and 82 patients had pain (Painful group). In 81% of the Painless group and 70% of the Painful group there was a type A dissection. The Painless group more frequently had a persistent disturbance of consciousness (44% vs. 6%, P<0.001), syncope (25% vs. 1%, P<0.001) and a focal neurologic deficit (19% vs. 2%, P=0.006) as presenting symptoms. Imaging study findings were not significantly different. Cerebral ischemia (50% vs. 1%, P<0.001) and cardiac tamponade (38% vs. 13%, P=0.01) were more frequent complications in the Painless group. In-hospital mortality was not significantly different (19% vs. 15%). However, the Painless group had a more unfavorable functional outcome on overall performance category (P<0.001). Conclusions: Painless AAD may be more frequent than previously reported. Painless AAD patients often present with a disturbance of consciousness or a neurologic deficit, and have a higher morbidity than painful AAD patients. (Circ J 2011; 75: 59-66)

著者

家高 洋 イエタカ ヒロシ Ietaka Hiroshi

出版者

大阪大学大学院文学研究科

雑誌

大阪大学大学院文学研究科紀要 (ISSN:13453548)

巻号頁・発行日

vol.49, pp.1-20, 2009-03-31

著者

Rimpei Kamamoto Kenji Suzuki Tetsuya Kawano Hiroshi Hanado Katsuhiro Nakagawa Yuki Kaneko

出版者

Meteorological Society of Japan

雑誌

SOLA (ISSN:13496476)

巻号頁・発行日

pp.2020-020, (Released:2020-06-03)

---

Two products from the Global Precipitation Measurement (GPM) Dual-frequency Precipitation Radar (DPR) algorithms, a flag of intense solid precipitation above the −10°C height (“flagHeavyIcePrecip”) and a classification of precipitation type (“typePrecip”) were validated by ground-based hydrometeor measurements and X-band multi-parameter (X-MP) radar observations of snow clouds on 4 February 2018. Contoured frequency by altitude diagrams of the X-MP radar reflectivity exhibited a significant difference between footprints flagged and unflagged by the “flagHeavyIcePrecip” algorithm, which indicated that the algorithm is reasonable. The hydrometeor classification (HC) by the X-MP radar, which was confirmed by microphysical evidence from ground-based hydrometeor measurements, suggested the existence of graupel in the footprints with “flagHeavyIcePrecip”. In addition, according to the information of the GPM DPR, the “flagHeavyIcePrecip” footprints were characterized by not only graupel but also large snowflakes. According to the information of X-MP radar HC, the “typePrecip” algorithm by the detection of “flagHeavyIcePrecip” was effective in classifying precipitation types of snow clouds, whereas it seems that there is room for improvement in the “typePrecip” algorithms based on the extended-DPRm-method and H-method.

著者

Atsushi Hozawa Takumi Hirata Hiroshi Yatsuya Yoshitaka Murakami Shinichi Kuriyama Ichiro Tsuji Daisuke Sugiyama Atsushi Satoh Sachiko Tanaka-Mizuno Katsuyuki Miura Hirotsugu Ueshima Tomonori Okamura

出版者

Japan Epidemiological Association

雑誌

Journal of Epidemiology (ISSN:09175040)

巻号頁・発行日

pp.JE20180124, (Released:2018-11-03)

参考文献数

20

被引用文献数

17

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Background: We sought to investigate the optimal values of BMI for the lowest risk of all-cause death and whether the optimal BMI differs according to smoking status in large-scale pooled analysis of 13 Japanese cohorts.Methods: Data from 179,987 participants of 13 well-qualified cohort studies conducted throughout Japan were used for our analysis. A cohort-stratified Cox proportional hazard model was used. P values for interactions were calculated based on the cross product of BMI and age, sex, or smoking status.Results: In the entire study population, all-cause mortality risk was lowest when the BMI was 22.0–24.9 kg/m2. This was also the case for selected healthy participants (never smoked, baseline total cholesterol level ≥4.1 mmol/L; the first 5 years of follow-up data were excluded). No effect modification of age, sex, or smoking status was observed. Regardless of their BMI, never smokers always had a lower all-cause mortality risk than did current smokers even with an ideal BMI in terms of mortality risk.Conclusion: A BMI of 22–24.9 kg/m2 correlated with the lowest risk of mortality, regardless of whether all participants or selected healthy participants were analyzed. The fact that smoking was more strongly associated with mortality than obesity emphasizes the urgency for effective anti-smoking programs.

著者

Naoyuki SHIGEMATSU Hiroshi TAKAMI Atsushi KUBO

出版者

The Japan Endocrine Society

雑誌

Endocrine Journal (ISSN:09188959)

巻号頁・発行日

pp.0609250043, (Released:2006-09-26)

被引用文献数

12 15

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Although surgery has been the mainstay of treatment for patients with well-differentiated thyroid cancer, the extents of thyroid resection and lymph node dissection adopted in Japan differ from those in other countries. Furthermore, regarding the indications for postoperative radiation therapy and hormonal therapy, and treatment modalities for cancer recurrence, there are marked discrepancies between Japan and other countries. A questionnaire survey was thus conducted among domestic and overseas thyroid surgeons to ascertain the actual treatment policy for well-differentiated thyroid cancer in Japan and various foreign countries. For small papillary carcinomas of 2.0 cm or less (T1), thyroid resection was more extensive in foreign countries than in Japan, although the extent of lymph node dissection was limited in the former. For large papillary carcinomas exceeding 3.0 cm (T2), on the other hand, total thyroidectomy was the treatment of first choice for all overseas respondents, but of only 20% in Japan, despite lymph node dissection being more extensive in Japan than in other countries. Overseas surgeons were much more likely to favor postoperative TSH suppression therapy and high-dose 131I therapy. For recurrence following surgery for papillary thyroid cancer, both domestic and overseas respondents indicated surgical resection to be the most common treatment option, and favored high-dose 131I therapy as well. In Japan, however, high-dose 131I therapy is available only in a few institutions. Such limited indications for high-dose 131I therapy in Japan may reflect a discrepancy in the frequency of total thyroidectomy, a prerequisite for postoperative high-dose 131I therapy, between Japan and other countries. This is the first questionnaire study conducted in both Japan and other countries in relation to treatment modalities for thyroid cancer. The results reveal that there is a clear disparity in treatment policies between Japan and foreign countries.

著者

Emiko KINOSHITA Kyoko HAYASHI Hiroshi KATAYAMA Toshimitsu HAYASHI Akio OBATA

出版者

Japan Society for Bioscience, Biotechnology, and Agrochemistry

雑誌

Bioscience, Biotechnology, and Biochemistry (ISSN:09168451)

巻号頁・発行日

vol.76, no.9, pp.1633-1638, 2012-09-23 (Released:2012-09-23)

参考文献数

27

被引用文献数

58

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Elderberry (Sambucus nigra L.) has traditionally been used for treating influenza and colds. We evaluated the antiviral effect of concentrated juice of elderberry (CJ-E) on the human influenza A virus (IFV). CJ-E had a relatively strong effect on IFV-infected mice, although its anti-IFV activity was weak in a cell culture system. The in vivo anti-IFV activities of the fractions were determined after separating CJ-E by ultrafiltration and anion-exchange chromatography. Oral administration of the high-molecular-weight fractions of CJ-E to IFV-infected mice suppressed viral replication in the bronchoalveolar lavage fluids (BALFs), and increased the level of the IFV-specific neutralizing antibody in the serum, as well as the level of secretory IgA in BALFs and feces. Fr. II from high-molecular-weight fraction HM, which contained acidic polysaccharides, showed relatively strong defense against IFV infection. We conclude that CJ-E had a beneficial effect by the stimulating immune response and preventing viral infection.

著者

Shinichi MOGAMI Yoshiki MITSUI Norihiro TAKAMUNE Daichi KITAMURA Hiroshi SARUWATARI Yu TAKAHASHI Kazunobu KONDO Hiroaki NAKAJIMA Hirokazu KAMEOKA

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

vol.E102-A, no.2, pp.458-463, 2019-02-01

被引用文献数

5

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In this letter, we propose a new blind source separation method, independent low-rank matrix analysis based on generalized Kullback-Leibler divergence. This method assumes a time-frequency-varying complex Poisson distribution as the source generative model, which yields convex optimization in the spectrogram estimation. The experimental evaluation confirms the proposed method's efficacy.

著者

Hiroshi Fujii Satoshi Ohta Keisuke Nonaka Yuichi Katayose Toshimi Matsumoto Tomoko Endo Terutaka Yoshioka Mitsuo Omura Takehiko Shimada

出版者

日本育種学会

雑誌

Breeding Science (ISSN:13447610)

巻号頁・発行日

pp.16060, (Released:2016-10-15)

被引用文献数

18

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Satsuma mandarins (Citrus unshiu Marc.) are the predominant cultivated citrus variety in Japan. Clarification of its origin would prove valuable for citrus taxonomy and mandarin breeding programs; however, current information is limited. We applied genome-wide genotyping using a 384 citrus single nucleotide polymorphism (SNP) array and MARCO computer software to investigate the satsuma mandarin parentage. Genotyping data from 206 validated SNPs were obtained to evaluate 67 citrus varieties and lines. A total of five parent–offspring relationships were newly found by MARCO based on the 206 SNP genotypes, indicating that ‘Kishuu mikan’ type mandarins (Citrus kinokuni hort. ex Tanaka accession ‘Kishuu mikan’ and ‘Nanfengmiju’) and ‘Kunenbo’ type mandarins (Citrus nobilis Lour. var. kunip Tanaka accession ‘Kunenbo’ and ‘Bendiguangju’) are possible parents of the satsuma mandarin. Moreover, cleaved amplified polymorphic sequences analysis showed that the genotypes of four regions in chloroplast DNA of ‘Kishuu mikan’ type mandarins were identical to that of the satsuma mandarin. Considering the historical background, satsuma mandarins may therefore derive from an occasional cross between a ‘Kishuu mikan’ type mandarin seed parent (derivative or synonym of ‘Nanfengmiju’) and a ‘Kunenbo’ type mandarin pollen parent (derivative or synonym of ‘Bendiguangju’).

著者

Yuki HIRAKAWA Tomomi YAMASAKI Ayako HARADA Seiji IWASA Hiroshi NARITA Shiro MIYAKE

出版者

The Japan Society for Analytical Chemistry

雑誌

Analytical Sciences (ISSN:09106340)

巻号頁・発行日

vol.34, no.5, pp.533-539, 2018-05-10 (Released:2018-05-10)

参考文献数

30

被引用文献数

18

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A simultaneous immunosensor based on surface plasmon resonance (SPR) was developed for determination of 3 pesticides —boscalid, clothianidin and nitenpyram— instead of the direct competitive enzyme-linked immunosorbent assays (dcELISAs) widely used as individual determination methods. Carboxy groups that introduced compounds to their pesticides were designed, and conjugates of them and bovine serum albumin were immobilized onto separate channels of the same sensor chip. When a mixture of 3 monoclonal antibodies reacted to each pesticide, and 3 pesticides were injected into the SPR immunosensor, each channel showed specific reactivity at 15 – 93 ng mL−1 for boscalid, 6.7 – 27 ng mL−1 for clothianidin, and 7.3 – 62 ng mL−1 for nitenpyram. Recovery tests using vegetables spiked with a mixture of 3 pesticides showed good results: 75 – 90%, 88 – 104%, and 72 – 105%, respectively, with a high correlation to results of the dcELISAs. The SPR immunosensor would be useful for the determination of pesticide residues in vegetables.

著者

Naoya Takeda Hiroshi Kajihara

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.23, no.1, pp.1-11, 2018-05-25 (Released:2018-05-26)

参考文献数

15

被引用文献数

3

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We have described a new genus and five new species of free-living marine flatworms in Schizorhynchia (Platyhelminthes: Rhabdocoela: Kalyptorhynchia) based on the material collected from sandy intertidal zones around Hokkaido, Northern Japan. These include Freddius tricaudatus gen. et sp. nov. (Cheliplanidae) and Proschizorhynchella caudociliata sp. nov., P. magnoliae sp. nov., P. shibazakii sp. nov., and P. shuttlecock sp. nov. (Schizorhynchidae). Based on this study, the number of confirmed species in the suborder Kalyptorhynchia discovered in Japanese waters has increased from one to six. Freddius tricaudatus gen. et sp. nov. possesses proboscis hooks that are so peculiar among Cheliplanidae that they warrant the establishment of a new genus.

著者

Fumiko Tomiyama Ryu Watanabe Hiroshi Fujii Yukiko Kamogawa Yoko Fujita Yuko Shirota Takashi Nakamichi Hiroshi Sato Tomonori Ishii Hideo Harigae

出版者

The Japanese Society of Internal Medicine

雑誌

Internal Medicine (ISSN:09182918)

巻号頁・発行日

vol.54, no.11, pp.1427-1432, 2015 (Released:2015-06-01)

参考文献数

18

被引用文献数

6

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A 71-year-old man was admitted to our department due to arthralgia and renal dysfunction. A physical examination disclosed swelling of the right shoulder and left wrist joints. Laboratory tests showed elevated serum IgG4 and creatinine levels, and magnetic resonance imaging of the wrist revealed bone erosion and synovitis. In addition, fluorodeoxyglucose positron emission tomography showed uptake in the submandibular glands, pancreas, kidneys, and affected joints and a renal biopsy revealed tubulointerstitial nephritis with the infiltration of IgG4+ plasma cells. The patient was subsequently diagnosed with IgG4-related disease (IgG4-RD) and successfully treated with corticosteroid therapy. This case suggests that erosive arthritis may occur in patients with IgG4-RD.

著者

Sakiko Itaya Zen Kobayashi Kokoro Ozaki Nozomu Sato Yoshiyuki Numasawa Kinya Ishikawa Takanori Yokota Hiroshi Matsuda Shuzo Shintani

出版者

The Japanese Society of Internal Medicine

雑誌

Internal Medicine (ISSN:09182918)

巻号頁・発行日

pp.0068-17, (Released:2018-02-09)

参考文献数

14

被引用文献数

4

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A 58-year-old man consulted our hospital due to a 2-year history of dysarthria and a 1-month history of blepharospasm. In addition to the ataxic dysarthria and blepharospasm, a neurological examination demonstrated slight ataxia of the trunk and lower limbs. Brain MRI demonstrated atrophy of the upper portion of the cerebellar vermis. Gene analysis established a diagnosis of spinocerebellar ataxia type 31 (SCA31). SPECT with the three-dimensional stereotaxic ROI template (3DSRT) software program demonstrated hyperperfusion in the lenticular nucleus and thalamus. Although the association between SCA31 and blepharospasm in our patient remains unclear, we considered that this combination might be more than coincidental.

著者

Tomoe NASUNO Kazuyoshi KIKUCHI Masuo NAKANO Yohei YAMADA Mikiko IKEDA Hiroshi TANIGUCHI

出版者

(公社)日本気象学会

雑誌

気象集誌. 第2輯 (ISSN:00261165)

巻号頁・発行日

vol.95, no.6, pp.345-368, 2017 (Released:2017-11-14)

参考文献数

79

被引用文献数

7

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By comparison with satellite and field observations, the comprehensive performance and potential utility of near real-time forecasts using Nonhydrostatic Icosahedral Atmospheric Model (NICAM) are demonstrated by exploiting the Cooperative Indian Ocean Experiment on Intraseasonal Variability in the Year 2011 (CINDY2011) / Dynamics of the Madden–Julian Oscillation (DYNAMO) campaign. A week-long forecast was run each day using a regionally stretched version of NICAM, with the finest mesh size of 14 km over the tropical Indian Ocean (IO), throughout the intensive observation period (IOP).  The simulated precipitation time series fairly represented the evolution and propagation of the observed Madden-Julian Oscillation (MJO) events, although a 30 % overprediction of precipitation over the IO domain (60–90°E, 10°S–10°N) was found on average. Frequencies of strong (> 40 mm day−1) precipitation were overpredicted, while those of weak precipitation were underpredicted against satellite observations. Compared with the field observations at Gan Island, the biases in precipitation frequency were less obvious, whereas the growth of lower to middle tropospheric dry (∼ 1 g kg−1) and warm (∼ 1 K) biases were found. Despite these mean biases, temporal variations of the moisture and zonal wind profiles including the MJO events were reasonably simulated. Using the forecast data the moisture and energy budgets during the IOP were investigated. The diagnosis using the 7-day-mean fields captured the observed features of the MJO events. Meanwhile, significant upward transport of moisture by the grid-resolved high-frequency variability was detected throughout the IOP. The relationship between these high-frequency effects and the simulated MJO or mean biases is also discussed.

著者

Nobuyasu Shiga Kohta Kido Satoshi Yasuda Bhola Panta Yuko Hanado Seiji Kawamura Hiroshi Hanado Kenichi Takizawa Masugi Inoue

出版者

(社)電子情報通信学会

雑誌

IEICE Communications Express (ISSN:21870136)

巻号頁・発行日

vol.6, no.2, pp.77-82, 2017 (Released:2017-02-01)

参考文献数

2

被引用文献数

12

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Wireless two-way interferometry (Wi-Wi) is the simplified version of “carrier phase based two-way satellite time and frequency transfer,” wherein a wireless communication technology is used instead of a satellite communication technology. We used the carrier phase of a 2.4 GHz ZigBee module to measure the variation of two rubidium clocks at remote sites. Since clocks in the ZigBee module are much less precise than rubidium clocks, the carrier phase of the ZigBee signal cannot be used to compare two rubidium clocks in a simple manner. Using a technique to cancel the clock error of transmitters, we demonstrated picosecond-level precision measurement of the time variation of clocks between two remote systems. This synchronization technique at picosecond-level precision opens the door to low-cost wireless positioning at millimeter accuracy.

著者

中谷 拓士 Hiroshi Nakatani

雑誌

人文論究 (ISSN:02866773)

巻号頁・発行日

vol.54, no.1, pp.75-88, 2004-05-25

著者

Yun-Shan Li Ming-Fen Song Hiroshi Kasai Kazuaki Kawai

出版者

日本環境変異原学会

雑誌

Genes and Environment (ISSN:18807046)

巻号頁・発行日

vol.35, no.3, pp.88-92, 2013 (Released:2013-09-03)

参考文献数

16

被引用文献数

1 10

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Human epidemiological studies have revealed significant increases in the cancer incidence rates by exposure to 100 mSv or higher doses of ionizing radiation. However, the relationship between lower doses of ionizing radiation and cancer incidence is still unclear. In general, oxidative DNA damage is closely related to cancer generation. We studied the oxidative DNA damage elicited by low dose ionizing irradiation. The γ-ray irradiation of a deoxyguanosine solution caused a linear increase in the 8-hydroxydeoxyguanosine (8-OHdG) levels, in the range of 20-300 mGy. Thus, 8-OHdG seems to be a good marker of the oxidative DNA damage caused by ionizing radiation. In contrast, in the case of the whole body X-ray irradiation of mice, the 8-OHdG levels in liver DNA and urine increased from about 500 and 200 mGy, respectively. These results indicate that living organisms have a defense mechanism against the oxidative damage caused by ionizing radiation. Considering the 8-OHdG levels as an ionizing radiation effect marker for living organisms, a threshold level of irradiation seems to exist for oxidative damage and tumorigenesis. Furthermore, diet imbalances increased radiation damage. Lifestyle may affect the radiation hazard.