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Mathematical Programming - Scenario generation is the construction of a discrete random vector to represent parameters of uncertain values in a stochastic program. Most approaches to scenario... 相似文献
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Analytical and Bioanalytical Chemistry - Accurate measurement and understanding of therapeutic uptake and metabolism is key in the drug development process. This work examines the amount of... 相似文献
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Indermeet Kohli Taylor L. Braunberger Amanda F. Nahhas Fatima N. Mirza Mohsen Mokhtari Alexis B. Lyons Nikiforos Kollias Eduardo Ruvolo Henry W. Lim Iltefat H. Hamzavi 《Photochemistry and photobiology》2020,96(1):208-214
Human skin is exposed to visible light (VL; 400–700 nm) and long-wavelength ultraviolet A1 (UVA1) radiation (370–400 nm) after the application of organic broad-spectrum sunscreens. The biologic effects of these wavelengths have been demonstrated; however, a dose–response has not been investigated. Ten subjects with Fitzpatrick skin phototype IV-VI were enrolled. Subjects were irradiated with 2 light sources (80–480 J cm−2): one comprising VL with less than 0.5% UVA1 (VL+UVA1) and the other pure VL. Skin responses were evaluated for 2 weeks using clinical and spectroscopic assessments. 4-mm punch biopsies were obtained from nonirradiated skin and sites irradiated with 480 J cm−2 of VL+UVA1 and pure VL 24 h after irradiation. Clinical and spectroscopic assessments demonstrated a robust response at VL+UVA1 sites compared with pure VL. Histology findings demonstrated a statistically significant increase in the marker of inflammation (P < 0.05) and proliferation (P < 0.05) at the irradiated sites compared with nonirradiated control. Threshold doses of VL+UVA1 resulting in biologic responses were calculated. Results indicate that approximately 2 h of sun exposure, which equates to VL+UVA1 dose (~400 J cm−2), is capable of inducing inflammation, immediate erythema and delayed tanning. These findings reinforce the need of photoprotection beyond the UV range. 相似文献
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Electrospray thrusters using ionic liquid (IL)‐based propellants are quickly gaining popularity in spacecraft design. Mass spectrometry is especially well‐suited to provide important knowledge on the fundamentals of how these systems work and on evaluating their efficiencies and impacts, given that the operating principles of electrospray thrusters closely mimics the mass spectrometry experiment – in both ions are generated by electrospray and then enter a vacuum. Here, electrospray thruster technology and IL‐based propellants are briefly introduced. This introduction is then followed by a discussion of mass spectrometry's current contribution to the study of IL‐based electrospray thrusters – with a focus on electrospray, dissociation, and spectroscopy studies – and a brief discussion of areas ripe for immediate contributions from the mass spectrometry community. 相似文献
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Stereochemical Studies of the Karlotoxin Class Using NMR Spectroscopy and DP4 Chemical‐Shift Analysis: Insights into their Mechanism of Action 下载免费PDF全文
Dr. Amanda L. Waters Dr. Joonseok Oh Prof. Allen R. Place Prof. Mark T. Hamann 《Angewandte Chemie (International ed. in English)》2015,54(52):15705-15710
After publication of karlotoxin 2 (KmTx2; 1 ), the harmful algal bloom dinoflagellate Karlodinium sp. was collected and scrutinized to identify additional biologically active complex polyketides. The structure of 1 was validated and revised at C49 using computational NMR tools including J‐based configurational analysis and chemical‐shift calculations. The characterization of two new compounds [KmTx8 ( 2 ) and KmTx9 ( 3 )] was achieved through overlaid 2D HSQC NMR techniques, while the relative configurations were determined by comparison to 1 and computational chemical‐shift calculations. The detailed evaluation of 2 using the NCI‐60 cell lines, NMR binding studies, and an assessment of the literature supports a mode of action (MoA) for targeting cancer‐cell membranes, especially of cytostatic tumors. This MoA is uniquely different from that of current agents employed in the control of cancers for which 2 shows sensitivity. 相似文献