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L. R. G. Valadon Mohamed Osman Rosemary S. Mummery 《Photochemistry and photobiology》1979,29(3):605-607
Abstract— Ten minutes of red irradiation (R) increased carotenogenesis in Verticillium agoricinum and this effect was reversed by 10min of far-red (FR) irradiation indicating that phytochrome is involved. A far-red minus red difference spectrum of a crude extract shows a peak at 670 nm and a dip at 750 nm wavelength, values slightly larger than higher plant phytochrome. indicating the presence of phytochrome. 相似文献
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A method for measuring the zeta potential of disks is described. Combining the hydrodynamic properties of a rotating disk, the solution of Laplace's equation for the potential, and the electrokinetic boundary condition, one obtains an equation that relates the zeta potential of the disk to the streaming potential in the disk's vicinity. Theory predicts a dependence of the streaming potential on the rotation rate raised to the 3/2 power. Theory also shows that placement of one reference electrode on the axis of rotation near the disk surface and the other far from the disk is favorable. Measurement of the streaming potential of silicon oxide and indium tin oxide in contact with a solution of potassium chloride demonstrated the expected 3/2 power dependence on rotation rate. The zeta potentials calculated from the combination of the theory and experimental data agreed with published values. 相似文献
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Rosemary Sheehan 《Supramolecular chemistry》2013,25(5):443-451
Computational protocols capable of modelling supramolecular complexes have been evaluated. The complexation of cations by crown ethers and quaternary ammonium ions by an oxacalix[3]arene are presented as examples. In the latter case reliable qualitative results were obtained using the semi-empirical PM3 method where guest LUMO and electrostatic potential energies have been shown to correlate with experimental binding data. The optimal method for more accurate results combines semi-empirical equilibrium geometry and property calculations with single point energy calculations at the HF/6–31G* or BP/6–31G* quantum mechanical level. 相似文献
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Dongseok Kim Dr. Rosemary L. Calabro Abdullah A. Masud Nadeesha L. Kothalawala Dr. Minsu Gu Dr. Seung-Yeon Kwak Won-Joon Son Dr. Kyu Young Hwang Dr. Hyeonho Choi Prof. Christopher I. Richards Prof. Doo Young Kim Prof. Byeong-Su Kim 《化学:亚洲杂志》2021,16(24):4155-4164
Fluorescent carbon nanodots (CDs) have been highlighted as promising semiconducting materials due to their outstanding chemical and optical properties. However, the intrinsic heterogeneity of CDs has impeded a clear understanding of the mechanisms behind their photophysical properties. In this study, as-prepared CDs are fractionated via chromatography to reduce their structural and chemical heterogeneity and analyzed through ensemble and single-particle spectroscopies. Many single particles reveal fluorescence intensity fluctuations between two or more discrete levels with bi-exponential decays. While the intrinsic τ1 components are uniform among single particles, the τ2 components from molecule-like emissions spans a wider range of lifetimes, reflecting the inhomogeneity of the surface states. Furthermore, it is concluded that the relative population and chemical states of surface functional groups in CDs have a significant impact on emissive states, brightness, blinking, stability, and lifetime distribution of photoluminescence. 相似文献
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Dianne?LangfordEmail author Rosemary?Hurford Makoto?Hashimoto Murat?Digicaylioglu Eliezer?Masliah 《BMC neuroscience》2005,6(1):8
Background
The blood brain barrier (BBB) is the first line of defence of the central nervous system (CNS) against circulating pathogens, such as HIV. The cytotoxic HIV protein, gp120, damages endothelial cells of the BBB, thereby compromising its integrity, which may lead to migration of HIV-infected cells into the brain. Fibroblast growth factor 2 (FGF2), produced primarily by astrocytes, promotes endothelial cell fitness and angiogenesis. We hypothesized that treatment of human umbilical vein endothelial cells (HUVEC) with FGF2 would protect the cells from gp120-mediated toxicity via endothelial cell survival signalling. 相似文献9.
We propose a new method for carrying out field-theoretic simulations of polymer systems under conditions of prescribed external stress, allowing for shape changes in the simulation box. A compact expression for the deviatoric stress tensor is derived in terms of the chain propagator, and it is used to monitor changes in the box shape according to a simple relaxation scheme. The method allows fully relaxed, stress free configurations to be obtained even in nontrivial morphologies, and it enables the study of morphology transitions induced by external stresses. 相似文献
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A variety of mass spectrometric techniques have been employed in the study of a series of structurally similar compounds used in the treatment of hypertension. The compounds, known collectively as angiotensin-converting enzyme (ACE) inhibitors, all share the amino acid residue proline or some variant thereof, as a common structural element. The gas phase fragmentation behavior of these compounds has been explored systematically using various instruments and techniques. An interesting dissociation process (rearrangement) unique to one of the compounds, lisinopril, has been investigated using isotopic labeling experiments and exact mass measurements. The general nature of the process has been probed through both the positive and negative ion analyses of fourteen related compounds exhibiting structural homology. 相似文献