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21.
C.C. Kuranz R.P. Drake C.M. Huntington C.M. Krauland C.A. Di Stefano M. Trantham M.J. Grosskopf S.R. Klein D.C. Marion 《High Energy Density Physics》2013,9(2):315-318
We have performed high-energy-density physics experiments with large radiative fluxes, relevant to radiative shocks in our universe. These experiments were performed at the Omega Laser facility and used a laser irradiance of 7.2 × 1014 W cm?2 to launch a Be disk into low-density Xe gas. The radiative shocks were observed early in time as the dense shocked Xe layer began to form. The average shock position indicates that the shock is moving over 130 km s?1. Data are compared to simulation output from the CRASH code, which was developed at the Center for Radiative Shock Hydrodynamics at the University of Michigan. 相似文献
22.
Hector Lopez Hernandez Abigail K. Grosskopf Lyndsay M. Stapleton Gillie Agmon Eric A. Appel 《Macromolecular bioscience》2019,19(1)
Drug delivery and cell transplantation require minimally invasive deployment strategies such as injection through clinically relevant high‐gauge needles. Supramolecular hydrogels comprising dodecyl‐modified hydroxypropylmethylcellulose and poly(ethylene glycol)‐block‐poly(lactic acid) have been previously demonstrated for the delivery of drugs and proteins. Here, it is demonstrated that the rheological properties of these hydrogels allow for facile injectability, an increase of cell viability after injection when compared to cell viabilities of cells injected in phosphate‐buffered saline, and homogeneous cell suspensions that do not settle. These hydrogels are injected at 1 mL min?1 with pressures less than 400 kPa, despite the solid‐like properties of the gel when at rest. The cell viabilities immediately after injection are greater than 86% for adult human dermal fibroblasts, human umbilical vein cells, smooth muscle cells, and human mesenchymal stem cells. Cells are shown to remain suspended and proliferate in the hydrogel at the same rate as observed in cell media. The work expands on the versatility of these hydrogels and lays a foundation for the codelivery of drugs, proteins, and cells. 相似文献
23.
The present paper is concerned with deriving conditions on technology which are required for additive separability of the associated profit function. The appropriate representation of technology in this case is the Luenberger shortage function. The paper shows that this function must be simultaneously input-and-output translation homothetic. 相似文献
24.
The relationship between Malmquist productivity change and profitability is developed in this paper. Our theoretical construct is applied to Swedish pharmacies. 相似文献
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26.
Angel TE Aryal UK Hengel SM Baker ES Kelly RT Robinson EW Smith RD 《Chemical Society reviews》2012,41(10):3912-3928
Mass spectrometry (MS)-based proteomics is emerging as a broadly effective means for identification, characterization, and quantification of proteins that are integral components of the processes essential for life. Characterization of proteins at the proteome and sub-proteome (e.g., the phosphoproteome, proteoglycome, or degradome/peptidome) levels provides a foundation for understanding fundamental aspects of biology. Emerging technologies such as ion mobility separations coupled with MS and microchip-based-proteome measurements combined with MS instrumentation and chromatographic separation techniques, such as nanoscale reversed phase liquid chromatography and capillary electrophoresis, show great promise for both broad undirected and targeted highly sensitive measurements. MS-based proteomics increasingly contribute to our understanding of the dynamics, interactions, and roles that proteins and peptides play, advancing our understanding of biology on a systems wide level for a wide range of applications including investigations of microbial communities, bioremediation, and human health. 相似文献
27.
Dr. José Cabrera Dr. Robin Padilla Dr. Miriam Bru Dr. Ronald Lindner Dr. Takeharu Kageyama Dr. Kristina Wilckens Dr. Shawna L. Balof Dr. Hans‐Jörg Schanz Dr. Richard Dehn Dr. J. Henrique Teles Dr. Stephan Deuerlein Dr. Kevin Müller Dr. Frank Rominger Dr. Michael Limbach 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(46):14717-14724
A set of heterogenized olefin‐metathesis catalysts, which consisted of Ru complexes with the H2ITap ligand (1,3‐bis(2′,6′‐dimethyl‐4′dimethyl aminophenyl)‐4,5‐dihydroimidazol‐2‐ylidene) that had been adsorbed onto a silica support, has been prepared. These complexes showed strong binding to the solid support without the need for tethering groups on the complex or functionalized silica. The catalysts were tested in the ring‐opening–ring‐closing‐metathesis (RO‐RCM) of cyclooctene (COE) and the self‐metathesis of methyl oleate under continuous‐flow conditions. The best complexes showed a TON>4000, which surpasses the previously reported materials that were either based on the Grubbs–Hoveyda II complex on silica or on the classical heterogeneous Re2O7/B2O3 catalyst. 相似文献
28.
Ruth A. Perez Nils Rehmann Sheila Crain Patricia LeBlanc Cheryl Craft Shawna MacKinnon Kelley Reeves Ian W. Burton John A. Walter Philipp Hess Michael A. Quilliam Jeremy E. Melanson 《Analytical and bioanalytical chemistry》2010,398(5):2243-2252
The production and certification of a series of azaspiracid (AZA) calibration solution reference materials is described. Azaspiracids were isolated from contaminated mussels, purified by preparative liquid chromatography and dried under vacuum to the anhydrous form. The purity was assessed by liquid chromatography–mass spectrometry and nuclear magnetic resonance spectroscopy. The final concentration of each AZA in a CD3OH stock solution was determined by quantitative NMR spectroscopy. This solution was then diluted very accurately in degassed, high purity methanol to a concentration of 1.47?±?0.08 μmol/L for CRM-AZA1, 1.52?±?0.05 μmol/L for CRM-AZA2, and 1.37?±?0.13 μmol/L for CRM-AZA3. Aliquots were dispensed into argon-filled glass ampoules, which were immediately flame-sealed. The calibration solutions are suitable for method development, method validation, calibration of liquid chromatography or mass spectrometry instrumentation and quality control of shellfish monitoring programs. 相似文献
29.
MacKinnon SL Cembella AD Burton IW Lewis N LeBlanc P Walter JA 《The Journal of organic chemistry》2006,71(23):8724-8731
Biosynthetic origins of the cyclic imine toxin 13-desmethyl spirolide C were determined by supplementing cultures of the toxigenic dinoflagellate Alexandrium ostenfeldii with stable isotope-labeled precursors [1,2-13C2]acetate, [1-13C]acetate, [2-13CD3]acetate, and [1,2-13C2,15N]glycine and measuring the incorporation patterns by 13C NMR spectroscopy. Despite partial scrambling of the acetate labels, the results show that most carbons of the macrocycle are polyketide-derived and that glycine is incorporated as an intact unit into the cyclic imine moiety. This work represents the first conclusive evidence that such cyclic imine toxins are polyketides and provides support for biosynthetic pathways previously defined for other polyether dinoflagellate toxins. 相似文献
30.
Horvath TD Matthews NI Stratton SL Mock DM Boysen G 《Analytical and bioanalytical chemistry》2011,401(9):2805-2810
Measurement of 3-hydroxyisovaleric acid (3HIA) in human urine has been shown to be a useful indicator of biotin status for a variety of clinical situations, including pregnancy. The work described herein presents a novel UPLC-MS/MS method for accurate and precise quantitation of urinary 3HIA. This method utilizes sample preparation prior to quantitation that has been simplified compared to the previous GC-MS method. To demonstrate the suitability of the UPLC-MS/MS method for human bio-monitoring, this method was used to measure 3-HIA in 64 human urine samples from eight healthy adults in whom marginal biotin deficiency had been induced experimentally by egg white feeding. 3HIA was detected in all specimens; the mean concentration [±standard deviation (SD)] was 80.6 ± 51 μM prior to inducing biotin deficiency. Mean excretion rate for 3HIA (expressed per mol urinary creatinine) before beginning the biotin-deficient diet was 8.5 ± 3.2 mmol 3HIA per mol creatinine and the mean increased threefold with deficiency. These specimens had been previously analyzed by GC-MS; the two data sets showed strong linear relationship with a correlation coefficient of 0.97. These results provide evidence that this method is suitable for bio-monitoring of biotin status in larger populations. 相似文献