Search Results - (Author, Cooperation:K. Arikawa)
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1Latest Papers from Table of Contents or Articles in PressT. Nagata ; M. Koyanagi ; H. Tsukamoto ; S. Saeki ; K. Isono ; Y. Shichida ; F. Tokunaga ; M. Kinoshita ; K. Arikawa ; A. Terakita
American Association for the Advancement of Science (AAAS)
Published 2012Staff ViewPublication Date: 2012-01-28Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Animals ; Cues ; Depth Perception ; Fixation, Ocular ; Light ; Locomotion ; Opsins/analysis/physiology ; Photoreceptor Cells, Invertebrate/chemistry/*physiology ; Predatory Behavior ; Spiders/*physiology ; Vision, OcularPublished by: -
2Articles: DFG German National LicensesStaff View
ISSN: 1476-4687Source: Nature Archives 1869 - 2009Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsNotes: [Auszug] SIR - The existence of extraocular pho-toreceptors is widespread within the animal kingdom1. In arthropods such receptors exist in various parts of the body2'7, but their function is unknown in any species. Here we demonstrate that the light sense of genitalia in butterflies, which is mediated by ...Type of Medium: Electronic ResourceURL: -
3Articles: DFG German National LicensesStaff View
ISSN: 0922-338XSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Process Engineering, Biotechnology, Nutrition TechnologyType of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesStaff View
ISSN: 0922-338XSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Process Engineering, Biotechnology, Nutrition TechnologyType of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesStaff View
ISSN: 0022-1910Keywords: Papilionid butterfly ; extraocular photoreception ; genitalia ; neurophysiologySource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyType of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesStaff View
ISSN: 0378-4363Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesStaff View
ISSN: 1432-1904Source: Springer Online Journal Archives 1860-2000Topics: BiologyChemistry and PharmacologyNatural Sciences in GeneralType of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesStaff View
ISSN: 1432-1904Source: Springer Online Journal Archives 1860-2000Topics: BiologyChemistry and PharmacologyNatural Sciences in GeneralType of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesStaff View
ISSN: 1432-1904Source: Springer Online Journal Archives 1860-2000Topics: BiologyChemistry and PharmacologyNatural Sciences in GeneralType of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesStaff View
ISSN: 1432-1351Keywords: Key words Lepidoptera ; Mating behavior ; Extraocular photoreceptor ; Genitalia ; ElectrophysiologySource: Springer Online Journal Archives 1860-2000Topics: BiologyMedicineNotes: Abstract 1. Butterflies have two pairs of extraocular photoreceptive neurons on the genitalia. Here we report that the genital photoreceptors have a crucial role in achieving copulation. 2. We first investigated mating behavior of the butterfly Papilio xuthus in an outdoor cage. The mating behavior consists of six steps: the male approaches the female (1), maneuvers into a ventor-to-ventor position with the female (2), searches the female's genitalia (3), clasps the genitalia (4), the pair copulates (5), and finally separates (6). 3. We bilaterally ablated the P1 pair of photoreceptors, in the males, and observed mating behavior with virgin females. Of the intact males 66% copulated successfully, whereas only about 25% of the treated males could copulate. About 40% of P1 ablated males stopped the mating behavior during step 3: the males could not locate the female's genitalia. P1 ablation in females did not have a clear effect in this study. 4. Electrophysiological measurements showed that the P1 response of a male drops sharply when it correctly locates the female's genitalia. We hypothesize that the sharp drop in the P1 response informs the male that the female's vagina is correctly positioned for penis insertion. The P1 ablated males never experience such␣a␣response drop, as there is no P1 response to begin with.Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesStaff View
ISSN: 1432-1351Keywords: Electrophysiology ; Lepidoptera ; Photoreceptor ; Spectral sensitivity ; VisionSource: Springer Online Journal Archives 1860-2000Topics: BiologyMedicineNotes: Abstract 1. The ommatidia of the butterfly Papilio have a fused and tiered rhabdom. The distal tier of the rhabdom is made up of four distal photoreceptors (R1–4), whereas the proximal tier is made up of four proximal (R5–8) and one basal photoreceptor cell (R9). 2. We first confirmed by light microscopy that the ommatidia of Papilio are not twisted, i.e. have the same spatial organization all about the longitudinal axis. The polarization method, previously applied to the distal tier, hence is applicable to identify the photoreceptor location from the peak angle of the polarization sensitivity. 3. We determined the polarization and spectral sensitivity of in total 109 proximal and basal photoreceptors in the lateral looking eye region. All of the photoreceptors were either green or red type, most of which fall into three classes as judged by the peak angles of the polarization sensitivity: around 40°, 150°, and 180° (= 0°) with respect to the dorso-ventral axis. The first two classes are formed by the proximal photoreceptors with straight microvilli oriented at the average angle of 39° (R6, 8) and 144° (R5, 7) respectively, and the third is formed by the basal photoreceptors R9 with straight microvilli oriented at 180° (= 0°). The mean polarization sensitivity (PS = maximal sensitivity/minimal sensitivity) was about 2. 4. 75% of the proximal and 48% of the basal photoreceptors were of the red type. 5. A single ommatidium of Papilio appears to contain two to four types of spectral receptors.Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesMakita, O. ; Ikushima, I. ; Matsumoto, N. ; Arikawa, K. ; Yamashita, Y. ; Takahashi, M.
Springer
Published 1999Staff ViewISSN: 1432-0509Keywords: Key words: Small bowel—Closed loop—Strangulating obstruction—Intestinal necrosis—Computed tomography—Multivariate analysis.Source: Springer Online Journal Archives 1860-2000Topics: MedicineNotes: Abstract Background: The purpose of this study was to evaluate computed tomographic (CT) findings for predicting the presence of intestinal necrosis in patients with closed loop and strangulating obstruction of the small bowel. Methods: Twenty-five patients with surgically confirmed closed loop and strangulating obstruction were divided into two groups with (n= 16) and without (n= 9) intestinal necrosis. By using univariate and multivariate statistical procedures, we evaluated the differences in CT findings between the two groups on the basis of the following six findings: bowel dilatation of strangulated loops (bowel dilatation), wall thickening of strangulated intestines (wall thickening), ascites, vascular dilatation of affected mesenteries (vascular dilatation), elevation of mesenteric attenuation (mesenteric attenuation), and radial distribution of the mesenteric vessels (radial distribution). Results: Of the six findings, ascites, vascular dilatation, mesenteric attenuation, and radial distribution provided significant discriminating findings between the two groups on univariate analysis. On multivariate analysis, mesenteric attenuation was the most important discriminative factor, followed by radial distribution and ascites. Using these three parameters, the CT was correlated with the surgical findings in 15 of the 16 patients in the necrosis group (sensitivity = 93.8%) and in eight of the nine patients in the nonnecrosis group (specificity = 88.9%). The overall accuracy was 92.0%. Conclusions: Mesenteric attenuation, radial distribution, and ascites, depicted on CT differentiate well between necrosis and nonnecrosis of the small bowelin patients with closed loop and strangulating obstruction.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesStaff View
ISSN: 1420-9071Keywords: Grapsid crab ; Hemigrapsus sanguineus ; compound eye ; circadian rhythm ; rhabdom ; visual pigment chromophoreSource: Springer Online Journal Archives 1860-2000Topics: BiologyMedicineNotes: Summary Under conditions of constant darkness, rhabdom volume and the amount of visual pigment chromophore show circadian changes in the compound eye of the crabHemigrapsus sanguineus. The present results indicate that an intrinsic circadian biological clock is involved in the control of the changes.Type of Medium: Electronic ResourceURL: