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81.
Masahiro Ueda Sanae Mizuno Akio Matsumura Fijio Sakan 《Optics and Lasers in Engineering》1996,25(1):13-23
A system for real-time monitoring of a dye has been constructed which enables us to measure the concentration and fluctuations of the three base colours. The method is based on light attenuation theory and its principle requires three different lasers having the three base colours. The system consisted of a semiconductor laser and argon ion laser for light sources, a photodiode for a light detector and a personal computer for data processing. Detection sensitivity for the dye concentration was a few and the system can be applied for practical uses. 相似文献
82.
Comparative cytogenetic analyses were carried out in six species of Brachycephalidae from southeastern Brazil. Barycholos ternetzi, Eleutherodactylus binotatus, Eleutherodactylus guentheri, Eleutherodactylus juipoca, Eleutherodactylus parvus and Eleutherodactylus sp. have 2n=22 karyotypes with a marked variation in the morphology of chromosome pairs 8, 10 and 11, which are of telocentric or metacentric types, resulting in FN=38, 40 and 44. Eleutherodactylus have a single chromosome pair bearing Ag-NOR, i.e. pair 1 in E. binotatus, pair 6 in E. guentheri and E. parvus, and pair 11 in E. juipoca and Eleutherodactylus sp. In contrast, B. ternetzi showed Ag-positive sites in the chromosome pairs 1, 4, 5, 9 and 11, and only one to three labelings per metaphase in each individual. Nevertheless, the main chromosome pair with Ag-NOR in the species seems to be the 11th, like in E. juipoca and Eleutherodactylus sp. The NOR site was confirmed by fluorescence in situ hybridization (FISH) technique in E. binotatus and in B. ternetzi, bearing 1p1p and 9p11p11p Ag-NOR pattern, respectively. All the species exhibited predominantly centromeric C-banding pattern, but interstitial bands have also been observed in some cases. In E. binotatus, there is an indication of geographical difference in the distribution of the interstitial C-bands. The fluorochromes GC-specific chromomycin A(3) (CMA(3)) and AT-specific 4',6-diamidino-2-phenylindole (DAPI), with distamycin A (DA) counterstaining, provided the molecular content of some repetitive regions in the karyotypes of the species. One male of E. binotatus presented an extensive heteromorphism, involving at least five different pairs, probably as a consequence of multiple reciprocal translocations. Such rearrangements might be responsible for the multivalent chain seen in the meiosis of this specimen, as well as in another male, although not exhibiting chromosome heteromorphism. The remaining males and those belonging to the other species have always shown 11 bivalents in diplotene and metaphase I cells. In all male specimens, metaphases II presented 11 chromosomes. Despite the observed discrepancies, the five species of Eleutherodactylus have a great uniformity in the 2n=22 karyotypes, suggesting an assemblage of species from southeastern and southern Brazil, in contrast to northern and northeastern assemblage which is characterized by higher diploid numbers. Undoubtedly, B. ternetzi could be included in that proposed assemblage, due to its karyotypic similarity with the Eleutherodactylus species, as evidenced in the present study. This fact strongly supports the close relationships of both genera, previously inferred on the basis of several characters shared by their species. 相似文献
83.
Size‐Selective Complexation and Extraction of Endohedral Metallofullerenes with Cycloparaphenylene 下载免费PDF全文
Yusuke Nakanishi Dr. Haruka Omachi Sanae Matsuura Prof. Dr. Yasumitsu Miyata Prof. Dr. Ryo Kitaura Prof. Dr. Yasutomo Segawa Prof. Dr. Kenichiro Itami Prof. Dr. Hisanori Shinohara 《Angewandte Chemie (International ed. in English)》2014,53(12):3102-3106
A new strategy for the non‐chromatographic extraction of metallofullerenes from solutions of arc‐processed raw soot is based on the size‐selective complexation with cycloparaphenylene (CPP). [11]CPP has a high affinity for Mx@C82 (x=1, 2); for example, Gd@C82 can be selectively extracted from a fullerene mixture by the addition of [11]CPP. This approach should open new opportunities in metallofullerene chemistry, including for the bulk extraction of metallofullerenes. 相似文献
84.
Masahiro Suzuki Sanae Owa Hirofusa Shirai Kenji Hanabusa 《Journal of polymer science. Part A, Polymer chemistry》2006,44(12):3817-3824
New poly(dimethylsiloxane)‐based polymer organogelators with L ‐lysine derivatives were synthesized on the basis of synthetically simple procedure, and their organogelation abilities were investigated. These polymer organogelators have a good organogelation ability and form organogels in many organic solvents. In the organogels, polymer gelators constructed a mesoporous structure with a pore size of about 1 μm formed by entanglement of the self‐assembled nanofibers. The L ‐lysine derivatives in the polymer gelators functioned as a gelation‐causing segment and the organogelation was induced by self‐assembly of the L ‐lysine segments through a hydrogen bonding interaction. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3817–3824, 2006 相似文献
85.
Matsuda S Shibayama H Hisama M Ohtsuki M Iwaki M 《Chemical & pharmaceutical bulletin》2008,56(3):292-297
We investigated the inhibitory effects of a novel amphiphilic ascorbic derivative, disodium isostearyl 2-O-L-ascorbyl phosphate (VCP-IS-2Na), synthesized from a hydrophilic ascorbic derivative, sodium-2-O-L-ascorbyl phosphate (VCP-Na), on melanogenesis in cultured human melanoma cells, normal human melanocytes, and three-dimensional cultured human skin models. Melanin synthesis in melanoma cells treated with VCP-IS-2Na at 300 muM and melanocytes treated with VCP-IS-2Na at 100 muM decreased to 23% and 52% of that in non-treated cells, respectively, and the cell viability was not affected. VCP-IS-2Na also significantly suppressed the cellular tyrosinase activity of melanoma cells and melanocytes. Melanin synthesis in human skin models was evaluated by macro- and microscopic observations of its pigmentation and quantitative measurements of melanin. Treatment of the human skin models with 1.0% VCP-IS-2Na did not inhibit cell viability, while melanin synthesis was decreased to 21% of that in the control. In contrast, L-ascorbic acid (VC) and VCP-Na did not seem to inhibit melanin synthesis and cellular tyrosinase activity. These results indicate that VCP-IS-2Na may be an effective whitening agent for the skin, and we expect the application of VCP-IS-2Na in the cosmetic industry. 相似文献
86.
Three novel hybrid polyketide-terpenoid metabolites were isolated from a Penicillium minioluteum strain. Their structures were determined by NMR spectroscopic analyses and X-ray crystallography. The proposed biosynthetic pathway including a unique retro-Claisen migration of methyl carbonate correlates the three compounds with berkeleydione and berkeleytrione. 相似文献
87.
Three new 14-membered macrolides, named aspergillides A, B, and C (1, 5, and 7), were isolated from marine-derived fungus Aspergillus ostianus strain 01F313, cultured in a medium composed of bromine-modified artificial seawater. The structures of the new compounds were determined by analyses of 1D and 2D NMR spectra. Their absolute configurations were elucidated by the modified Mosher's method and chemical conversions. The new compounds showed cytotoxic activity against mouse lymphocytic leukemia cells (L1210). 相似文献
88.
Osman Altnta Hüseyin Irmak Shigeyoshi Owa H.M. Srivastava 《Applied Mathematics Letters》2007,20(12):1218-1222
In the present work, the authors determine coefficient bounds for functions in certain subclasses of starlike and convex functions of complex order, which are introduced here by means of a family of nonhomogeneous Cauchy–Euler differential equations. Several corollaries and consequences of the main results are also considered. 相似文献
89.
Sanaâ Saoiabi Sanae El Asri Abdelaziz Laghzizil Sylvie Masse Jerome L. Ackerman 《Journal of solid state chemistry》2012
Organofunctionalized apatite nanoparticles were prepared using a one step process involving dissolution/precipitation of natural phosphate rock and covalent grafting of nitrilotris(methylene)triphosphonate (NTP). The synthesized materials were characterized by Brunauer–Emmett–Teller (BET) surface measurement, thermogravimetry, inductively coupled plasma emission spectroscopy (ICP–ES), elemental analysis, multinuclear solid state cross-polarization/magic angle spinning (CP/MAS) and single-pulse NMR spectroscopy, transmission electron microscopy (TEM) and energy dispersive X-ray analysis (EDXA). After grafting BET measurements yielded particle specific surface areas ranging from 88 to 193 m2 g?1 depending on the grafted phosphonate. The results show that the surfaces of the nanoapatite particles can be covered with functional groups bound through a variable number of R–P–O–Ca bonds to render them organoapatites. 相似文献
90.
New l-valine derivatives, which have a positively charged group, function as excellent hydrogelators that can gel pure water, saline, and aqueous solutions containing inorganic acids and salts at 0.2 wt %. 相似文献