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111.
Solid-phase extraction microtips are important devices in modern bioanalytics, as they allow miniaturized sample preparation for mass spectrometric analysis. Here we introduce the use of cotton wool for the preparation of filter-free HILIC SPE microtips. To this end, pieces of cotton wool pads (approximately 500 μg) were packed into 10 μL pipet tips. The performance of the tips was evaluated for microscale purification of tryptic IgG Fc N-glycopeptides. Cotton wool HILIC SPE microtips allowed the removal of salts, most nonglycosylated peptides, and detergents such as SDS from glycoconjugate samples. MALDI-TOF-MS glycopeptide profiles were very repeatable with different tips as well as reused tips, and very similar profiles were obtained with different brands of cotton wool pads. In addition, we used cotton HILIC microtips to purify N-glycans after N-glycosidase F treatment of IgG and transferrin followed by MALDI-TOF-MS detection. In conclusion, we establish cotton wool microtips for glycan and glycopeptide purification with subsequent mass spectrometric detection. 相似文献
112.
Theresa N Ngoma Maurice Monjerezi John F Leslie Brighton M Mvumi Jagger JW Harvey Limbikani Matumba 《Journal of the science of food and agriculture》2024,104(2):561-571
Postharvest management is critical to attaining household food, nutrition, and income security. Hermetic grain storage bags offer an effective pesticide-free way to protect stored grain against fungal and insect infestation. We evaluated articles indexed in the Web of Science that included experiments comparing the storage efficacy of conventional and hermetic storage bags based on grain germination rate, insect infestation, physical damage, mycotoxin contamination, and changes in weight and moisture content. Compared with grain stored in hermetic bags, grain stored in conventional bags lost 3.6-fold more seed viability, contained 42-fold more insects, had 11-fold more physical damage, and lost 23-fold more grain weight, while grain moisture levels were similar for both hermetic and conventional storage bags. Mycotoxin contamination levels were not as frequently assessed. Levels could be low in grain stored in both types of bags, or levels could be low in hermetic bags and significantly higher in conventional bags. The improved properties of grain stored in hermetic bags can increase food security and household income by providing safe storage options for maintaining seed germinability, and for consumption and/or sale when food supplies are high, or when prices are low. Hermetic bags are economically feasible for use by subsistence farmers in Sub-Saharan Africa for grain for household consumption and for carrying-over seed for planting in the next season. Additional studies are needed to verify the mycotoxin contamination results and to determine if there are differences in functional food characteristics, e.g. flavor and cooking properties, that have not been as comprehensively studied. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
113.
R. W. Rydin D. Maurice T. H. Courtney 《Metallurgical and Materials Transactions A》1993,24(1):175-185
The motions of grinding media and powder in an attritor canister were studied by means of filming the agitated charge and
frame-by-frame scrutiny of the footage. In conjunction with auxiliary experiments, this permitted semiquantitative analysis
of the milling action. In particular, the mill can be divided into several regions characterized by different balances between
direct impacts and rolling/sliding of the grinding media. Simple calculations suggest that impacts are more capable of effecting
mechanical alloying (MA) than are rolling or sliding events in an attritor. Powder circulation within an operating mill was
also investigated. Based on the results and the accompanying analysis, concepts for improved attritor design are presented.
D. Maurice is formerly a Graduate Student, Department of Materials Science and Engineering, University of Virginia, Charlottesville,
VA 22903 相似文献
114.
The aim of the work summarized in this paper is the theoretical modelling of laminated composite shells of arbitrary shape, in order to: improve the calculus of shear stresses, and especially to avoid shear correction factors; account for continuity conditions of displacements and transverse shear stresses at layer interfaces as well as compatibility conditions of transverse shear stresses on the bonding surfaces; estimate the relevance of shear refinements, of membrane refinements and of the transverse stretching beyond standard kinematics; and to analyse the sensitivity to edge effects for significant boundary conditions. 相似文献
115.
Szymusiak Ronald; McGinty Dennis; Shouse Margaret N.; Shepard Diane; Sterman Maurice B. 《Canadian Metallurgical Quarterly》1990,104(1):217
Sensorimotor electroencephalogram (EEG) frequencies in cats were evaluated with power spectral analysis before and after 3 doses of atropine sulfate. All doses of atropine tested caused enhanced EEG slow waves (0–7 Hz) and spindles (8–25 Hz) during waking immobility, and postdrug frequency profiles during slow-wave sleep and waking immobility were identical. With 0.75 mg/kg atropine, movement (head movement, locomotion) resulted in EEG desynchronization and reduced power in all frequencies less than 24 Hz. After 1.5 or 3.0 mg/kg atropine, power in low frequencies remained elevated during movement, but power in spindle frequencies was significantly reduced compared with other states. During active REM sleep after 1.5 mg/kg atropine, power in spindle frequencies was significantly lower than that during quiet REM sleep. These results indicate that the sensorimotor cortical EEG in cats is under the control of multiple systems. At least 1 of these systems is active during movement, and its actions are resistant to muscarinic receptor blockade. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
116.
117.
Theobald CE Mosha Maurice R Bennink 《Journal of the science of food and agriculture》2005,85(9):1513-1522
This study was conducted to evaluate protein quality, acceptability and storage stability of processed cereal–bean–sardine composite foods for pre‐school age children in Tanzania. Four composite products namely corn–bean–sardine meal (CBSM), bean meal (BM), sorghum–bean–sardine meal (SBSM) and rice–bean–sardine meal (RBSM) were formulated to maximize the amino acid score for pre‐school age children and were processed by extrusion, drum‐processing and conventional cooking. The products were evaluated for true protein digestibility (TPD) and protein digestibility‐corrected amino acid score (PDCAAS). The TPD and PDCAAS were highest in the extruded products. The TPD values for the products ranged from 82 to 93%. The PDCAAS values for the composite foods were 64–86% and were greater than the minimum value of 60% recommended by FAO/WHO/UNU. There were no significant (p > 0.05) variations in the amino acid contents for foods processed by extrusion, drum‐processing or conventional cooking. Threonine was most limiting in the CBSM, SBSM and RBSM while methionine + cysteine were most limiting in the BM. Sensory evaluation showed that, relative to the traditional cornmeal—Uji, the extruded CBSM and SBSM had significantly superior (p ≤ 0.05) texture and highly acceptable color and taste. Storage of the products up to 16 weeks at 38 °C resulted in a small but significant increase (p ≤ 0.05) in the malondialdehyde concentrations; nevertheless, the levels remained within the acceptable range found in processed commercial supplements. Total acids, pH and organoleptic attributes did not change significantly (p > 0.05) during storage and the foods were acceptable to the end of the storage period. Copyright © 2005 Society of Chemical Industry 相似文献
118.
Maurice H. ter Beek Gabriele Lenzini Marinella Petrocchi 《Electronic Notes in Theoretical Computer Science》2005,128(5):105
In [Kleijn, J., Team Automata for CSCW – A Survey –, Petri Net Technology for Communication-Based Systems—Advances in Petri Nets, LNCS 2472, Springer, 2003, 295–320], Kleijn presented a survey of the use of team automata for the specification and analysis of phenomena from the field of computer supported cooperative work, in particular notions related to groupware systems. In this paper we present a survey of the use of team automata for the specification and analysis of some issues from the field of security. In particular, we show how team automata can adequately be used to model and verify various access control policies, multicast/broadcast communication protocols, and general (cryptographic) communication protocols. 相似文献
119.
120.
Synchronizations in Team Automata for Groupware Systems 总被引:7,自引:0,他引:7
Maurice H. ter Beek Clarence A. Ellis Jetty Kleijn Grzegorz Rozenberg 《Computer Supported Cooperative Work (CSCW)》2003,12(1):21-69
Team automata have been proposed in Ellis (1997) as a formal framework for modeling both the conceptual and the architectural level of groupware systems. Here we define team automata in a mathematically precise way in terms of component automata which synchronizeon certain executions of actions.At the conceptual level, our model serves as a formal framework in whichbasic groupware notions can be rigorously defined and studied.At the architectural level, team automata can be used as building blocksin the design of groupware systems. 相似文献