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121.
Dark-grown cells of Euglena gracilis var. bacillaris incubated on resting medium for 7 days lose half of their extractable and phototransformable protochlorophyll(ide) [Pchl(ide)]. The readily-utilized substrates glutamate and malate bring about a regeneration of both pools of Pchl(ide) to the levels found in growing cells, without causing cell division during the period of regeneration. Light does not cause a regeneration of total extractable Pchl(ide) to the levels found in growing cells, and the complete regeneration of phototransformable Pchl(ide) seen probably results from conversion of non-transformable Pchl(ide) to transformable Pchl(ide). Optimal glutamate, malate, and light in any combination are no better in causing phototransformable Pchl(ide) regeneration than any one treatment alone, indicating that the Pchl(ide) pool size is limited by other factors. The regeneration of phototransformable Pchl(ide) induced by light or substrates is insensitive to inhibitors of protein synthesis on 80 S cytoplasmic ribosomes (cycloheximide) or on 70 S chloroplast ribosomes (streptomycin). Cycloheximide, however, induces the regeneration of phototransformable Pchl(ide) in darkness in the absencc of externally-added substrates. Since cycloheximide is known to induce paramylum breakdown under the same conditions, it is likely that this process can provide internal substrates and/or reducing power for phototransformable Pchl(ide) regeneration. Possible mechanisms of regulation of formation of Pchl(ide)635 in Euglena are discussed and compared with regulation of Pchl(ide)650 in higher plants. 相似文献
122.
123.
Radu Custelcean Dr. Jerome Bosano Peter V. Bonnesen Dr. Vilmos Kertesz Dr. Benjamin P. Hay Dr. 《Angewandte Chemie (International ed. in English)》2009,48(22):4025-4029
Custom built : A promising new approach towards more efficient self‐assembled cage receptors through computer‐aided design is demonstrated. The resulting M4L6 tetrahedral cage, internally functionalized with accurately positioned urea hydrogen‐bonding groups (see structure; yellow: predicted, blue: experimental, space‐filling: SO42?), proved to be a remarkably strong sulfate receptor in water.
124.
Giuseppe M. Coclite Gisèle R. Goldstein Jerome A. Goldstein 《Journal of Differential Equations》2009,246(6):2434-3971
Of concern is the nonlinear uniformly parabolic problem
125.
126.
Savonnet M Camarata A Canivet J Bazer-Bachi D Bats N Lecocq V Pinel C Farrusseng D 《Dalton transactions (Cambridge, England : 2003)》2012,41(14):3945-3948
We successively introduce new catalytic centers through click reaction into MOFs and modify their environment by addition of lipophilic groups. The resulting bifunctionalized MOF provides an optimized balance between basicity and lipophilicity and shows outstanding performance for the transesterification reaction. 相似文献
127.
R. Mahalakshmi J. M. Linet S. N. Priya B. M. Boaz S. X. Jesuraja S. Jerome Das 《Crystal Research and Technology》2006,41(11):1072-1075
Borono phenylalanine abbreviated as BPA is a biologically important compound which is obtained from L‐Phenylalanine (C9H11NO2) in which a boron atom is bonded. BPA is an amino acid analogue, helpful in the treatment of glioblastoma multiforme, a highly malignant form of brain tumor is crystallized in silica gel under pH 6.0 by single diffusion method in a period of 30 minutes. The grown crystals were characterized by x‐ray powder diffraction, Fourier Transform infrared spectroscopy and visible ultraviolet spectroscopy. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
128.
In this article, we discuss the use of computational models in the study of voltage operated channels (VOCs) for bio-electronic applications. Electrochemical and fluid–mechanical ionic transport are described through the coupled use of systems of partial and ordinary differential equations (PDEs and ODEs). Functional iteration techniques for system decoupling and mixed–hybridized finite element discretization methods are proposed and validated in the simulation of realistic problems in Electrophysiology and Biochemistry. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
129.
Yabashi M Hastings JB Zolotorev MS Mimura H Yumoto H Matsuyama S Yamauchi K Ishikawa T 《Physical review letters》2006,97(8):084802
An experimental scheme to realize single-shot spectrometry for the diagnostics of x-ray free-electron lasers (XFELs) is presented. The combination of an ultraprecisely figured mirror and a perfect crystal form a simple, high-precision spectrometer that can cover an energy range from a few eV to a hundred eV with high resolution. The application of the spectrometer to determine XFEL pulse widths was investigated theoretically and experimentally. It has been shown that the present system can determine pulse widths from sub-fs to ps in a single shot even for spontaneous radiation. The system can be easily extended to even shorter pulses. 相似文献
130.
Fan L Fallahi M Hader J Zakharian AR Moloney JV Murray JT Bedford R Stolz W Koch SW 《Optics letters》2006,31(24):3612-3614
We propose an efficient coherent power scaling scheme, the multichip vertical-external-cavity surface-emitting laser (VECSEL), in which the waste heat generated in the active region is distributed on multi-VECSEL chips such that the pump level at the thermal rollover is significantly increased. The advantages of this laser are discussed, and the development and demonstration of a two-chip VECSEL operating around 970 nm with over 19 W of output power is presented. 相似文献