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11.
ABSTRACT:   High- and multi-frequency acoustic measurement systems and the multi-frequency inversion (MFI) method have been used to measure spatial distributions and abundances of zooplankton by size. In this study, the calibration method for high- and multi-frequency systems was developed and the validation of MFI method was carried out by scatterer measurement. The standard sphere calibration method that has not been applied to such high- and multi-frequencies was applied to calibrate our high- and multi-frequency system, TAPS-6 (Tracor Acoustic Profiling System, BAE Systems). An optimum size of standard sphere of tungsten carbide of 1 mm radius was derived to have a small target strength variation for the six frequencies of TAPS-6, and the practicability and precision of the standard sphere calibration method was confirmed for those frequencies. A school or cluster of dummy scatterers of zooplankton with small tungsten carbide spheres were designed to validate the MFI method, and volume back-scattering strength values were measured by the multi-frequency system. By comparing the result of the inversion with their real composition, the features of the MFI method could be validated and examined.  相似文献   
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13.
We report on the experimental quantum teleportation of strongly nonclassical wave packets of light. To perform this full quantum operation while preserving and retrieving the fragile nonclassicality of the input state, we have developed a broadband, zero-dispersion teleportation apparatus that works in conjunction with time-resolved state preparation equipment. Our approach brings within experimental reach a whole new set of hybrid protocols involving discrete- and continuous-variable techniques in quantum information processing for optical sciences.  相似文献   
14.
Tumor necrosis factor (TNF) receptor-associated factors (TRAFs) were identified as signal transducers for the tumor necrosis factor receptor (TNFR) superfamily. In this study, we cloned and characterized two genes that encode chicken TNFR-II and TRAF5. The initial cDNA fragments were obtained by suppressive subtractive hybridization (SSH) of chicken spleen cells with or without lipopolysaccharide stimulation (Salmonella typhimurium SL1181 (RE-mutant)). The results showed that chicken TNFR-II is 1518 bp in length with an open reading frame (ORF) of 1386 bp having 31% homology with human TNFR-II. Expression analysis of chicken TNFR-II revealed that it is highly expressed in the spleen and bursa of Fabricius. The chicken cell lines IN24, MSB1 and 1104B express TNFR-II abundantly. The time course analysis of expression in spleen, bursa of Fabricius and IN24 cell line showed that TNFR-II is maximally expressed at 6 h after stimulation in bursa of Fabricius and after 8 h stimulation in the IN24 cell line. With regard to TRAF5, the complete sequence was 1936 bp in length with an ORF of 1671 bp that showed 71.3% homology with human TRAF5. Expression analysis showed that, among the tissues examined, TRAF5 was strongly expressed in spleen and bursa of Fabricius, while among the cell lines examined, it was maximally expressed in IN24. Thus, both genes were expressed in the same tissues and cell line among examined materials. These results suggest that chicken TNFR-II may interact with TRAF5 adaptor protein to complete its signal transduction pathway.  相似文献   
15.
The existence of CD3(+)CD4(-)CD8(-) T cells in thymus and spleen has already been known. However, because of the presence of large amounts of thrombocytes in peripheral blood (PB), the proportion of CD3(+)CD4(-)CD8(-) T cells in PB has yet to be investigated. Therefore, the proportion of peripheral T cell-subsets was investigated in 6-week-old chickens. The percentage of CD3(+) cells, CD4(+) cells, CD8 alpha(+) cells, CD8 beta(+), and CD3(+)CD4(-)CD8(-) cells was 76%, 41%, 14%, 5%, and 15%, respectively. The proportion of CD3(+)CD4(-)CD8(-) cells in PB increased during egg-laying periods and in chickens treated with an analog of estrogen, while it decreased with age and in response to restraint stress. All of the CD3(+)CD4(-)CD8(-) cells expressed TCR1, and did not have NK activity. CD3(+)CD4(-)CD8(-) cells represent about 60% of peripheral TCR1(+) cells. These findings indicate that the proportion of CD3(+)CD4(-)CD8(-) cells is regulated by the endocrine and nerve systems.  相似文献   
16.
We histopathologically and immunohistochemically investigated a case of malignant lymphoma that spontaneously developed in a male common marmoset at two years of age. Beginning at two years four months of age, the animal had an enlargement of the submandibular and inguinal lymph nodes, small subcutaneous nodules near the right breast and an approximately fivefold increase in peripheral lymphocyte count compared with the previous examination value. The postmortem findings at two years eight months of age showed lymphadenopathy with enlargement of the thymus and spleen. Small- to intermediate-sized neoplastic lymphocytes had diffusely proliferated in the enlarged nodes. The neoplastic cells were pleomorphic and had irregularly shaped nuclei. The nuclear chromatin staining revealed hyperchromatism in the small-sized cells, and the intermediate-sized cells exhibited vesicular staining. An immunohistochemical examination indicated that the neoplastic lymphocytes were positive for CD3 and negative for CD20, thus suggesting that they had originated from T cells. In addition, the proliferation of high endothelial venules and reactive epithelioid histiocytes was observed. Scattered tingible body-laden macrophages were infrequently detected. Neoplastic lymphocytes were also observed in the thymus, spleen, heart, lungs, liver, kidneys, adrenal glands and femoral and sternal bone marrow. This malignant lymphoma in a young male common marmoset was considered to fit the category of “peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS)” according to the new WHO system of classification.  相似文献   
17.
Cortical microtubules (MTs) in differentiating compression wood tracheids of Taxus cuspidata stems were visualized by confocal laser microscopy. They were oriented obliquely at an angle of about 45° to the tracheid axis during formation of the secondary wall. Artificial inclination altered the pattern of alignment of MTs. Banding MTs were helically oriented late during the formation of the secondary walls. These results indicate that MTs might control the orientation and localized deposition of cellulose microfibrils in the secondary walls of compression wood tracheids.Part of this report was presented at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996  相似文献   
18.
Unconditional quantum teleportation   总被引:5,自引:0,他引:5  
Quantum teleportation of optical coherent states was demonstrated experimentally using squeezed-state entanglement. The quantum nature of the achieved teleportation was verified by the experimentally determined fidelity Fexp = 0.58 +/- 0.02, which describes the match between input and output states. A fidelity greater than 0.5 is not possible for coherent states without the use of entanglement. This is the first realization of unconditional quantum teleportation where every state entering the device is actually teleported.  相似文献   
19.
A new cell line named CCF‐K104 predominantly consisting of fibroblastic cells showed optimal growth at temperatures from 25 °C to 30 °C. Serial morphological changes in the cells induced by Cyprinid herpesvirus 3 (CyHV‐3) included cytoplasmic vacuolar formation, cell rounding and detachment. Mature virions were purified from CyHV‐3‐infected CCF‐K104 cells by sucrose gradient ultracentrifugation and had a typical herpesvirus structure on electron microscopy. Infectious CyHV‐3 was produced stably in CCF‐K104 cells over 30 viral passages. Our findings showed that CCF‐K104 is a useful cell line for isolation and productive replication of CyHV‐3. A temperature shift from 25 °C to 15 °C or 35 °C did not allow serial morphological changes as observed at 25 °C for 14 days. Under the same conditions, real‐time PCR showed that CyHV‐3 was present with low viral DNA loads, suggesting that CyHV‐3 may establish latent infection in CCF‐K104 cells. Amplification of the left and right terminal repeat sequences of the CyHV‐3 genome arranged in a head‐to‐tail manner was detected by nested PCR following an upshift in temperature from 25 °C to 35 °C. The PCR results suggested that the circular genome may represent a latent form of CyHV‐3.  相似文献   
20.
The effect of blue LED on melatonin secretion, feeding behaviour and growth was addressed in Holstein female dairy calves. In Exp.1, six animals (8 weeks old, 97 ± 4.1 kg BW) were exposed to yellow or blue LED for 2 hr before darkness over 7 days under a long‐day photoperiod (LDPP). In Exp. 2, six animals (8 weeks old, 88.5 ± 4.8 kg BW) were exposed to blue light from a white LED all daytime or a yellow LED for 2 hr before the darkness of LDPP (blue light cut) over 3 weeks. In Exp. 1, blue light mildly suppressed melatonin secretion during the 2‐hr treatment but did not affect the timing of the nightly melatonin rise. However, the rise in nighty melatonin levels was higher with yellow than blue LED. In Exp. 2, white LED completely suppressed melatonin secretion during the 2‐hr treatment, but plasma melatonin concentrations were similar during the darkness. Grass hay intake, rumination time, frequency of water intake and body weight gain were higher in animals exposed to the yellow rather than the white LED. Overall results indicate that exposure to blue light from white LEDs under an LDPP suppresses melatonin secretion and might negatively impact the development of female dairy calves.  相似文献   
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