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501.
Akara Sasaki Kou Ikejima Shigeru Aoki Nobuyuki Azuma Noboru Kashimura Minoru Wada 《Environmental Biology of Fishes》2003,66(4):307-311
Luminescence of the pony fish, Leiognathus elongatus, was observed in the natural environment during nighttime diving. The light was emitted from the lateroventral portion of the body, as bright rectangular-shaped luminescence patches turned on and off periodically. Luminescent fish had a distinct clear patch on the flank through which light was emitted, whereas non-luminous fish did not have such a clear patch. Both luminous and non-luminous fish were found within a shoal, where non-luminous individuals were chased by luminous ones. From previous morphological studies, the luminous and non-luminous individuals are likely to be male and female, respectively. Our observations provide field evidence that the luminescence functions as intraspecific communications in L. elongatus. 相似文献
502.
Physiological Links in Firefly Flash Code Evolution 总被引:4,自引:0,他引:4
New and reassessed neurophysiological observations on dialog fireflies permit (1) parsimonious inferences about the origin and fixation of light emission in the primeval firefly, (2) proof of widespread involvement of a stable species-specific minimal stimulus–response interval in timed flashing behaviors of both genders, (3) strengthening of the evidence for certain normally latent flash control intervals common to both male and female, (4) assignment of possible roles in the evolution of time-coded courting dialog to these data, and (5) evaluation of the evolutionary status of certain present-day species. 相似文献
503.
X‐ray‐induced luminescence computed tomography (XLCT) is an emerging molecular imaging. Challenges in improving spatial resolution and reducing the scan time in a whole‐body field of view (FOV) still remain for practical in vivo applications. In this study, we present a novel XLCT technique capable of obtaining three‐dimensional (3D) images from a single snapshot. Specifically, a customed two‐planar‐mirror component is integrated into a cone beam XLCT imaging system to obtain multiple optical views of an object simultaneously. Furthermore, a compressive sensing based algorithm is adopted to improve the efficiency of 3D XLCT image reconstruction. Numerical simulations and experiments were conducted to validate the single snapshot X‐ray‐induced luminescence computed tomography (SS‐XLCT). The results show that the 3D distribution of the nanophosphor targets can be visualized much faster than conventional cone beam XLCT imaging method that was used in our comparisons while maintaining comparable spatial resolution as in conventional XLCT imaging. SS‐XLCT has the potential to harness the power of XLCT for rapid whole‐body in vivo molecular imaging of small animals. 相似文献
504.
Zeyu Zhang Yawei Qu Yu Cao Xiaojing Shi Hongbo Guo Xiaojun Zhang Sheng Zheng Haifeng Liu Zhenhua Hu Jie Tian 《Journal of biophotonics》2020,13(3)
Intraoperative Cerenkov luminescence imaging (CLI) can effectively improve the performance of tumor surgery. Nevertheless, the existing approaches are still unsatisfying to the clinical demands of open surgery. This study develops a novel intraoperative in vivo CLI approach to investigate the potential and value of Cerenkov luminescence (CL) image‐guided surgery. A system characterized with high sensitivity (19.61 kBq mL?1 18F‐FDG) and desirable spatial resolution (88.34 μm) is developed. CL image‐guided surgery is performed on colorectal cancer (CRC) models of mice and swine. Tumor surgery is guided by the static CL images, and the resection quality is evaluated quantitatively and contrasted with other imaging modalities exemplified by bioluminescence imaging (BLI). The in vivo results demonstrated the effectiveness of the proposed intraoperative CLI approach for removing primary and metastatic CRC. Safety of performing in vivo CL image‐guided surgery is verified as well through radiation measurements of related staffs. Overall, the developed intraoperative in vivo CLI approach can efficiently improve the cancer treatment. 相似文献
505.
Lars-Göran Sundblad Göran Samuelsson Bosse Wigge Per Gardeström 《Photosynthesis research》1990,23(3):269-282
Two green algal species, Chlamydomonas reinhardtii and Scenedesmus obliquus, exhibited a relative maximum during the decay of luminescence, when adapted to low CO2 conditions that was not observed in high CO2 adapted cells.From the kinetics of transient changes in the level of dark fluorescence, after illumination and parallel to the luminescence maxima, it was concluded that the maximum in Scenedesmus was mainly related to a decrease in nonphotochemical quenching, whereas in Chlamydomonas the maximum was mainly related to a dark reduction of the primary PS II acceptor QA.ATP/ADP ratios from low CO2 adapted Scenedesmus showed transient high levels after a dark/light transition that was not observed in high CO2 adapted cells. After 30 s of illumination the ATP/ADP ratios however stabilized at the same steady state level as in high CO2 adapted cells.Dark addition of HCO3
- to low CO2 adapted cells of Chlamydomonas resulted in a rapid transient quenching of luminescence that was not observed in low CO2 adapted cells of neither species.It is concluded that the luminescence maxima present in both low CO2 adapted Scenedesmus and Chlamydomonas reflect adaptation of the cells to low CO2 conditions. It is further suggested that the difference in mechanistic origin of luminescence maxima in the two species reflects differences in adaptation.Abbreviations ADP
adenosine-diphosphate
- ATP
adenosine-triphosphate
- Ci
inorganic carbon
- FD
dark fluorescence recorded under dark adapted conditions
- F0
fluorescence with all reaction centers open
- FV
variable fluorescence
- PS I
photosystem I
- PS II
photosystem II
- QA
the first quinone acceptor of PS II 相似文献