著者
Ichiro TSUDA Edgar KOERNER Hiroshi SHIMIZU Bioholonics Research Project Research Development Corporation of Japan Bioholonics Research Project Research Development Corporation of Japan Faculty of Pharmaceutical Sciences Department of Biophysics University of Tokyo
雑誌
Progress of theoretical physics = Progress of theoretical physics (ISSN:0033068X)
巻号頁・発行日
vol.78, no.1, pp.51-71, 1987-07-25

A model which can perform learning, formation of memory without teacher for successive memory recalls is presented. The philosophical background of the study is summarized. The investigated network consists of two sets both composed of asynchronously firing model neurons. One set of neurons is responsible for the field effect, and the other is introduced as an input/output module. The field effect is given in the form of the system's self-response. It is shown that positive end negative global feedbacks by the field effect play an essential role in the successive recall of stored patterns. The possibility that these proposed mechanisms are implemented in the brain is discussed. We obtained a quasi-deterministic law on the level of a macrovariable concerning a random successive recall of memory representations by taking a Lorenz-plot of this macrovariable. We show that this macroscopic order is deterministic chaos steming from collapse of tori and this type of chaos can be an effective gadget of memory traces.
著者
Naoshi Hirata Shiro Ohmi Shin'ichi Sakai Kei Katsumata Satoshi Matsumoto Tetsuo Takanami Akira Yamamoto Takashi Iidaka Taku Urabe Mayumi Sekine Tooru Ooida Fumihito Yamazaki Hiroshi Katao Yasuhiro Umeda Masao Nakamura Norihiko Seto Takeshi Matsushima Hiroshi Shimizu Japanese University Group of the Urgent Joint
出版者
The Seismological Society of Japan, The Volcanological Society of Japan, The Geodetic Society of Japan
雑誌
Journal of Physics of the Earth (ISSN:00223743)
巻号頁・発行日
vol.44, no.4, pp.317-328, 1996 (Released:2009-04-30)
参考文献数
21
被引用文献数
41 43

A disastrous earthquake with a magnitude of 7.2 hit the southern part of Hyogo Prefecture on January 17, 1995. The mainshock was located on an active fault of the Arima-Takatsuki-Rokko fault system. Its focal mechanism was consistent with a right-lateral strike-slip fault trending N40°E. Three days after the occurrence of the mainshock, we started to install a highly dense seismic array in and around the fault area of the quake. Two permanent regional seismic networks of more than 30 stations covered the entire area of 200 km × 200 km. The temporarily installed array of 27 stations spanned the fault area of 15 km × 50 km. All data were telemetered to a temporary observation center at Uji. We located about 3, 100 aftershocks in real time for 1 month using an Internet connection between seismic networks. The aftershock area extended 70 km trending northeast to southwest. Hypocenters determined by the network were delivered automatically through the Internet. We found that the aftershock distribution was heterogeneous in space and time: seven clusters of hypocenters were identified and temporary variation in the rate of occurrence of aftershocks had a periodic component with periods of a half of day, 1 day, and 3 days, that are superimposed on decaying of the rate following Omori's law.
著者
Naoshi KONDO Makoto KURAMOTO Hiroshi SHIMIZU Yuichi OGAWA Mitsutaka KURITA Takahisa NISHIZU Vui Kiong CHONG Kazuya YAMAMOTO
出版者
Asian Agricultural and Biological Engineering Association
雑誌
Engineering in Agriculture, Environment and Food (ISSN:18818366)
巻号頁・発行日
vol.2, no.2, pp.54-59, 2009 (Released:2009-04-04)
参考文献数
14

As basic research to develop a machine vision system to detect rotten mandarin orange, the extraction and identification of fluorescent substances contained in rotten parts of mandarin orange were conducted, and the excitation and fluorescence wavelengths of the substance were determined. Although it has been reported that damaged orange fruit skins are often fluoresced by UV light, it was suggested that fluorescent substances exist not only in the rotten parts of skins but also the normal parts of skins from this research. The fluorescent substances were extracted from 1kg of mandarin peel, and NMR analysis and mass spectrometry were conducted. From this experiment, it was found that the fluorescent substance was quite possibly heptamethylflavone and that the excitation and fluorescent wavelengths of one of the substances were 360 to 375nm and 530 to 550nm, respectively.
著者
Yoshihiro Miyake Hideki Tada Masafumi Yano Hiroshi Shimizu
出版者
Japan Society for Cell Biology
雑誌
Cell Structure and Function (ISSN:03867196)
巻号頁・発行日
vol.19, no.6, pp.363-370, 1994 (Released:2006-03-27)
参考文献数
18
被引用文献数
10 16

The relationship between intracellular period modulation and external environment change was investigated from the viewpoint of internal information coding in Physarum plasmodium. For the external conditions, concentration changes of attractant (galactose) and repellent (KC1) were used, and the internal responses were measured as the thickness oscillation of the plasmodium. (i) Period of the intracellular oscillation decreased when the concentration of attractant was increased and when the concentration of repellent was decreased, (ii) The period increased when the attractant was decreased and when the repellent was increased, (iii) The larger concentration change induced the larger period modulation, (iv) These responses were observed when the change of concentration was greater than a threshold value. From these results, it was clarified that the relative change in environmental condition is encoded on the relative period modulation in intracellular oscillation. This means that the period change does not directly represent the environment itself but represents the change of its condition. Thus, it is further suggested that the plasmodium estimates the environmental condition based on the relationship between the previous external condition and the present one.
著者
増田 彰正 田中 剛 朝倉 純子 清水 洋 Akimasa MASUDA Tsuyoshi TANAKA Junko ASAKURA Hiroshi SHIMIZU
雑誌
南極資料 (ISSN:00857289)
巻号頁・発行日
vol.58, pp.197-203, 1977-03

やまと隕石(j),(k)および(m)の中の希土類元素(REE),Ba,Rb,Srを安定同位体希釈法によって定量した.(j)については,任意に二つの部分をとって分析した(提供された試料は,やや粗い粉末試料だった).最も代表的な希土類元素相互存在度を示すと考えられるLeedeyコンドライトの値で規格化すると,(k)は最も小さい分化を示すが,Euによく見られる異常は別として,GdとDyとの間に不連続性が見られるのが特徴である.(m)と(k)は,成因的な関連が深いと判断された.(j)の二回の定量値の間には,興味深い,系統的な差がある.(m)と(k)との関連,および(j)の内部的分化は,共に,もとの母体小惑星内での溶融と結晶分化の効果を強く示唆すると解釈できる.
著者
Nobuyuki Okahashi Shuichi Kawana Junko Iida Hiroshi Shimizu Fumio Matsuda
出版者
The Mass Spectrometry Society of Japan
雑誌
Mass Spectrometry (ISSN:2187137X)
巻号頁・発行日
vol.8, no.1, pp.A0073, 2019-08-30 (Released:2019-08-30)
参考文献数
15
被引用文献数
1 3

Isotope labeling measurements using mass spectrometry can provide informative insights on the metabolic systems of various organisms. The detailed identification of carbon positions included in the fragment ions of dicarboxylic and tricarboxylic acids in central carbon metabolism is needed for precise interpretation of the metabolic states. In this study, fragment ions containing the carbon backbone cleavage of dicarboxylic and tricarboxylic in the Krebs cycle were investigated by using gas chromatography (GC)-electron ionization (EI)-MS and GC-EI-MS/MS. The positions of decarboxylation in the dicarboxylic and tricarboxylic acids were successfully identified by analyses using position-specific 13C-labeled standards prepared by in vitro enzymatic reactions. For example, carboxyl groups of C1 and C6 of trimethylsilyl (TMS)- and tert-butyldimethylsilyl (TBDMS)-derivatized malic and citric acids were primarily cleaved by EI. MS/MS analyses were also performed, and fragment ions of TBDMS-citric and α-ketoglutaric acids (αKG) with the loss of two carboxyl groups in collision-induced dissociation (CID) were observed.
著者
Nobuyuki Okahashi Shuichi Kawana Junko Iida Hiroshi Shimizu Fumio Matsuda
出版者
The Mass Spectrometry Society of Japan
雑誌
Mass Spectrometry (ISSN:2187137X)
巻号頁・発行日
pp.A0073, (Released:2019-08-01)
参考文献数
15
被引用文献数
3

Isotope labeling measurements using mass spectrometry can provide informative insights on the metabolic systems of various organisms. The detailed identification of carbon positions included in the fragment ions of dicarboxylic and tricarboxylic acids in central carbon metabolism is needed for precise interpretation of the metabolic states. In this study, fragment ions containing the carbon backbone cleavage of dicarboxylic and tricarboxylic in the Krebs cycle were investigated by using gas chromatography (GC)-electron ionization (EI)-MS and GC-EI-MS/MS. The positions of decarboxylation in the dicarboxylic and tricarboxylic acids were successfully identified by analyses using position-specific 13C-labeled standards prepared by in vitro enzymatic reactions. For example, carboxyl groups of C1 and C6 of trimethylsilyl (TMS)- and tert-butyldimethylsilyl (TBDMS)-derivatized malic and citric acids were primarily cleaved by EI. MS/MS analyses were also performed, and fragment ions of TBDMS-citric and α-ketoglutaric acids (αKG) with the loss of two carboxyl groups in collision-induced dissociation (CID) were observed.
著者
Hiroshi SHIMIZU Takayuki HOSHI Kenji NAKAMURA Jai-Eok PARK
出版者
日本生物環境工学会
雑誌
Environmental Control in Biology (ISSN:1880554X)
巻号頁・発行日
vol.53, no.2, pp.85-88, 2015 (Released:2015-06-17)
参考文献数
9
被引用文献数
1

An ultrasonic pollination device was developed to achieve effective artificial pollination of strawberries in artificial light type plant factories. A phase array of hundreds of ultrasonic transducers was appropriately controlled and focused on one point in space, and it is possible to generate a force at any position in space. The force was modulated at 30 Hz which is the characteristic frequency of strawberry flower. The pollination experiment was conducted using the strawberry variety F1 Elan (Fragaria×ananassa). The total weight of the strawberries harvested over 22 days was 1.22 kg, and the average weights of individual strawberry fruits were 9.1 g.
著者
Asuka SUTO Masahiro YAMASAKI Yukari TAKASAKI Yasuyuki FUJITA Riichiro ABE Hiroshi SHIMIZU Hiroshi OHTA Mitsuyoshi TAKIGUCHI
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.13-0098, (Released:2013-07-16)
被引用文献数
2 4

Due to the lack of a gold standard method in canine lipoprotein analysis, it is unclear whether canine high-density lipoprotein (HDL) and low-density lipoprotein (LDL) can be accurately evaluated by the lipoprotein analysis methods used for dogs. This study investigated whether the ultracentrifugation-precipitation (U-P) method was suitable as a gold standard method for analyzing canine lipoprotein. First, the U-P method was compared with a gel permeation high performance liquid chromatography system (GP-HPLC). The concentrations of canine HDL-cholesterol (HDL-C) and LDL-cholesterol (LDL-C) determined by the U-P method correlated closely with those determined by GP-HPLC. However, the canine HDL-C concentration determined by the U-P method was lower than that by GP-HPLC, and the canine LDL-C concentration by the U-P method was higher than that by GP-HPLC. This study showed that some of the canine HDL could be precipitated with heparin manganese chloride solution. Second, the [HDL] and [LDL] fractions separated by the U-P method were analyzed by LC-MS/MS. The [HDL] fraction was found to contain only apolipoprotein A-I, which is an apolipoprotein of HDL, whereas the [LDL] fraction contained both apolipoprotein A-I and apolipoprotein B-100, which is an apolipoprotein of LDL. This data showed that a certain lipoprotein that includes apolipoprotein A-I might precipitate with canine LDL by use of heparin manganese chloride solution. These results indicated that the U-P method is not currently a gold standard method for analyzing canine lipoproteins.