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81.
Shotgun lipidomics is a well-suited approach to monitor lipid alterations due to its ability to scan for varying lipid types on a global, class and individual species level. However, the ability to perform high-throughput shotgun lipidomics has remained challenging due to time-consuming data processing and hardware limitations. To increase the throughput nature of shotgun lipidomics, an automated shotgun lipidomics approach is described utilizing conventional low flow gradient liquid chromatography (LC) analysis (post-injection) coupled with multiple sample injections per sample (on a lipid scan per injection basis). The proposed automated multi-injection approach resulted in a reproducible lipid scanning period of 2.5 min (in a 4.5 min total data acquisition period), thereby providing a sufficient scanning period for performing either mass spectrometric or tandem mass spectrometric analyses. In addition to being simple, robust and reproducible, this approach was also constructed to be cost-effective by using common LC instrumentation and customizable as the data acquisition period can be tailored to perform different scan types, period lengths and scan numbers. Combined with a strategy to create multiple lipid-specific aliquots per sample, the overall approach provides a simple and efficient platform to perform high-throughput lipid profiling. 相似文献
82.
Jackie Cutsinger George Galster Harold Wolman Royce Hanson Douglas Towns 《Journal of Urban Affairs》2005,27(3):235-259
Abstract: Twelve conceptually distinct dimensions of land use patterns are operationalized for 50 large US metropolitan areas using a battery of indices. Common patterns of variation in these indices across metropolitan areas are discerned using correlation and factor analyses. We find that: (1) seven principal components best summarize the dimensions of housing and employment land uses, (2) metro areas often exhibit both high and low levels of sprawl‐like patterns across the seven components, and (3) housing and employment aspects of sprawl‐like patterns differ in nature. Thus, land use patterns prove multi‐dimensional in both theory and practice. Exploratory analyses indicate: (1) little regional variation in land use patterns, (2) metro areas with larger populations are more dense/continuous with greater housing centrality and concentration of employment in the core, (3) older areas have higher degrees of housing concentration and employment in the core, (4) constrained areas evince greater density/continuity, and (5) inter‐metropolitan variations in several dimensions of land use patterns are not well explained by population, age, growth patterns, or topographical constraints on development. Results imply that policymakers must carefully unravel which land use dimension is causing undesirable outcomes, and then devise precise policy instruments to change only this dimension. 相似文献
83.
84.
The rate of dissolution of rock salt in drilling mud was measured as a function of flow rate and temperature under conditions simulating those in a well. A water based drilling mud, containing about 10% solids and additives was used, as well as a polymer “mud” composed of a Xanthan gum polymer solution and 5% salt, but no solids. The non-Newtonian muds were pumped through a “slit” flow cell, with a slab of rock salt flush with one side of the cell wall. The data (including water over the same range of conditions) were described by a mass transfer coefficient, and were correlated in dimensionless form based on the theoretical solution of the analogous heat transfer problem, adapted to non-Newtonian fluids. The non-Newtonian properties were described by an effective viscosity, which is consistent with either the power law or Bingham plastic viscosity model. 相似文献
85.
Five experiments tested the prediction, from a simple chaining model, that interleaving irrelevant material will substantially disrupt immediate serial recall. Exp 1 interpolated long or short words between items in an auditory digit span test. These 2 "sandwich" conditions disrupted recall to an equal but moderate extent. Exp 2 presented mixed lists of digits and words, cuing one or the other before or after presentation. Precuing led to substantially better recall. Exp 3 used articulatory suppression to rule out the hypothesis that recall was protected from the sandwich effect by subvocal rehearsal. Exp 4 combined the sandwich effect with a concurrent task, finding clear effects of both but no interaction. Exp 5 showed that the predictability of interpolated material did not influence recall. These results can be explained by adding an attentional preprocessor to standard chaining models. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Jackie Groves 《Computer Fraud & Security》2002,2002(9):8-11
IntroductionIt often frustrates me that some of our European neighbours are far more advanced in establishing large-scale biometric deployments than UK enterprises. How can this be? The major obstacle appears to be the restricted viewpoint of organizations in the UK when it comes to considering biometric technology. 相似文献
87.
Jackie Groves 《Computer Fraud & Security》2002,2002(1):9-12
Pay attention please! Today’s test is all about passwords. Hands up anyone who has ever stored their password or PIN number in any of the following ‘secure’ places? 相似文献
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89.
Jiraporn Kantapan Nampeung Anukul Nipapan Leetrakool Gwenaël Rolin Jackie Vergote Nathupakorn Dechsupa 《International journal of molecular sciences》2021,22(16)
Cell-based therapy is a highly promising treatment paradigm in ischemic disease due to its ability to repair tissue when implanted into a damaged site. These therapeutic effects involve a strong paracrine component resulting from the high levels of bioactive molecules secreted in response to the local microenvironment. Therefore, the secreted therapeutic can be modulated by preconditioning the cells during in vitro culturing. Herein, we investigated the potential use of magnetic resonance imaging (MRI) probes, the “iron–quercetin complex” or IronQ, for preconditioning peripheral blood mononuclear cells (PBMCs) to expand proangiogenic cells and enhance their secreted therapeutic factors. PBMCs obtained from healthy donor blood were cultured in the presence of the iron–quercetin complex. Differentiated preconditioning PBMCs were characterized by immunostaining. An enzyme-linked immunosorbent assay was carried out to describe the secreted cytokines. In vitro migration and tubular formation using human umbilical vein endothelial cells (HUVECs) were completed to investigate the proangiogenic efficacy. IronQ significantly increased mononuclear progenitor cell proliferation and differentiation into spindle-shape-like cells, expressing both hematopoietic and stromal cell markers. The expansion increased the number of colony-forming units (CFU-Hill). The conditioned medium obtained from IronQ-treated PBMCs contained high levels of interleukin 8 (IL-8), IL-10, urokinase-type-plasminogen-activator (uPA), matrix metalloproteinases-9 (MMP-9), and tumor necrosis factor-alpha (TNF-α), as well as augmented migration and capillary network formation of HUVECs and fibroblast cells, in vitro. Our study demonstrated that the IronQ-preconditioning PBMC protocol could enhance the angiogenic and reparative potential of non-mobilized PBMCs. This protocol might be used as an adjunctive strategy to improve the efficacy of cell therapy when using PBMCs for ischemic diseases and chronic wounds. However, in vivo assessment is required for further validation. 相似文献
90.
Brightwell G Boerema J Mills J Mowat E Pulford D 《International journal of food microbiology》2006,109(1-2):47-53
We examined the bacterial community present on an Intralox conveyor belt system in an operating lamb boning room by sequencing the 16S ribosomal DNA (rDNA) of bacteria extracted in the presence or absence of cultivation. RFLP patterns for 16S rDNA clone library and cultures were generated using HaeIII and MspI restriction endonucleases. 16S rDNA amplicons produced 8 distinct RFLP pattern groups. RFLP groups I-IV were represented in the clone library and RFLP groups I and V-VIII were represented amongst the cultured isolates. Partial DNA sequences from each RFLP group revealed that all group I, II and VIII representatives were Pseudomonas spp., group III were Sphingomonas spp., group IV clones were most similar to an uncultured alpha proteobacterium, group V was similar to a Serratia spp., group VI with an Alcaligenes spp., and group VII with Microbacterium spp. Sphingomonads were numerically dominant in the culture-independent clone library and along with the group IV alpha proteobacterium were not represented amongst the cultured isolates. Serratia, Alcaligenes and Microbacterium spp. were only represented with cultured isolates. Pseudomonads were detected by both culture-dependent (84% of isolates) and culture-independent (12.5% of clones) methods and their presence at high frequency does pose the risk of product spoilage if transferred onto meat stored under aerobic conditions. The detection of sphingomonads in large numbers by the culture-independent method demands further analysis because sphingomonads may represent a new source of meat spoilage that has not been previously recognised in the meat processing environment. The 16S rDNA collections generated by both methods were important at representing the diversity of the bacterial population associated with an Intralox conveyor belt system. 相似文献