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91.
Conley R Liu C Qian J Kewish CM Macrander AT Yan H Kang HC Maser J Stephenson GB 《The Review of scientific instruments》2008,79(5):053104
A multilayer Laue lens (MLL) is an x-ray focusing optic fabricated from a multilayer structure consisting of thousands of layers of two different materials produced by thin-film deposition. The sequence of layer thicknesses is controlled to satisfy the Fresnel zone plate law and the multilayer is sectioned to form the optic. An improved MLL geometry can be created by growing each layer with an in-plane thickness gradient to form a wedge, so that every interface makes the correct angle with the incident beam for symmetric Bragg diffraction. The ultimate hard x-ray focusing performance of a wedged MLL has been predicted to be significantly better than that of a nonwedged MLL, giving subnanometer resolution with high efficiency. Here, we describe a method to deposit the multilayer structure needed for an ideal wedged MLL and report our initial deposition results to produce these structures. 相似文献
92.
Anna Bertova Szilvia Kontar Zoltan Polozsanyi Martin Simkovic Zuzana Rosenbergova Martin Rebros Zdena Sulova Albert Breier Denisa Imrichova 《International journal of molecular sciences》2022,23(18)
The expression of the membrane ABCB1 transporter in neoplastic cells is one of the most common causes of reduced sensitivity to chemotherapy. In our previous study, we investigated the effect of a single culture of ABCB1-negative (S) and ABCB1-positive variants of L1210 cells (R and T) in the presence of sulforaphane (SFN). We demonstrated that SFN induces the onset of autophagy more markedly in S cells than in R or T cells. In the current study, we focused on the effect of the repeated culture of S, R and T cells in SFN-containing media. The repeated cultures increased the onset of autophagy compared to the simple culture, mainly in S cells and to a lesser extent in R and T cells, as indicated by changes in the cellular content of 16 and 18 kDa fragments of LC3B protein or changes in the specific staining of cells with monodansylcadaverine. We conclude that SFN affects ABCB1-negative S cells more than ABCB1-positive R and T cells during repeated culturing. Changes in cell sensitivity to SFN appear to be related to the expression of genes for cell-cycle checkpoints, such as cyclins and cyclin-dependent kinases. 相似文献
93.
Albert Weichselbraun 《Journal of Intelligent Information Systems》2011,37(2):119-137
One key property of the Semantic Web is its support for interoperability. Recent research in this area focuses on the integration
of multiple data sources to facilitate tasks such as ontology learning, user query expansion and context recognition. The
growing popularity of such machups and the rising number of Web APIs supporting links between heterogeneous data providers
asks for intelligent methods to spare remote resources and minimize delays imposed by queries to external data sources. This
paper suggests a cost and utility model for optimizing such queries by leveraging optimal stopping theory from business economics:
applications are modeled as decision makers that look for optimal answer sets. Queries to remote resources cause additional
cost but retrieve valuable information which improves the estimation of the answer set’s utility. Optimal stopping optimizes
the trade-off between query cost and answer utility yielding optimal query strategies for remote resources. These strategies
are compared to conventional approaches in an extensive evaluation based on real world response times taken from seven popular
Web services. 相似文献
94.
Daria S. Chulpanova Albert A. Rizvanov Valeriya V. Solovyeva 《International journal of molecular sciences》2023,24(1)
Cancer stem cells (CSCs) are a population of tumor cells that share similar properties to normal stem cells. CSCs are able to promote tumor progression and recurrence due to their resistance to chemotherapy and ability to stimulate angiogenesis and differentiate into non-CSCs. Cancer stem cells can also create a significant immunosuppressive environment around themselves by suppressing the activity of effector immune cells and recruiting cells that support tumor escape from immune response. The immunosuppressive effect of CSCs can be mediated by receptors located on their surface, as well as by secreted molecules, which transfer immunosuppressive signals to the cells of tumor microenvironment. In this article, the ability of CSCs to regulate the antitumor immune response and a contribution of CSC-derived EVs into the avoidance of the immune response are discussed. 相似文献
95.
96.
Phytic acid (PA), found in cereal and legume staple foods, is considered an antinutrient for iron (Fe) and zinc (Zn). Amongst numerous factors, temperature has a substantial effect on PA synthesis in seeds of legumes. PA, Fe, and Zn concentrations were determined for mature seeds of eleven lentil genotypes grown under simulated long term temperature regimes representative of Saskatoon, Canada (decreasing temperatures) and Lucknow, India (increasing temperatures). PA and Zn concentrations in lentil seeds were significantly higher in the rising temperature regime (8.8 mg/g and 69 mg/kg, respectively) than in the decreasing temperature regime (6.7 mg/g and 61 mg/kg, respectively). Fe concentrations followed the same trend (116 vs. 113 mg/kg). The cooler temperatures of temperate summers might be an important factor in the production of seeds with lower PA concentrations. These results are relevant to the development of biofortification strategies aimed at lowering the PA content in staple crops. 相似文献
97.
Gabriele Mocciaro Simona DAmore Benjamin Jenkins Richard Kay Antonio Murgia Luis Vicente Herrera-Marcos Stefanie Neun Alice P. Sowton Zoe Hall Susana Alejandra Palma-Duran Giuseppe Palasciano Frank Reimann Andrew Murray Patrizia Suppressa Carlo Sabb Antonio Moschetta Albert Koulman Julian L. Griffin Michele Vacca 《International journal of molecular sciences》2022,23(12)
The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors characterised by central obesity, atherogenic dyslipidaemia, and changes in the circulating lipidome; the underlying mechanisms that lead to this lipid remodelling have only been partially elucidated. This study used an integrated “omics” approach (untargeted whole serum lipidomics, targeted proteomics, and lipoprotein lipidomics) to study lipoprotein remodelling and HDL composition in subjects with central obesity diagnosed with MetS (vs. controls). Compared with healthy subjects, MetS patients showed higher free fatty acids, diglycerides, phosphatidylcholines, and triglycerides, particularly those enriched in products of de novo lipogenesis. On the other hand, the “lysophosphatidylcholines to phosphatidylcholines” and “cholesteryl ester to free cholesterol” ratios were reduced, pointing to a lower activity of lecithin cholesterol acyltransferase (LCAT) in MetS; LCAT activity (directly measured and predicted by lipidomic ratios) was positively correlated with high-density lipoprotein cholesterol (HDL-C) and negatively correlated with body mass index (BMI) and insulin resistance. Moreover, many phosphatidylcholines and sphingomyelins were significantly lower in the HDL of MetS patients and strongly correlated with BMI and clinical metabolic parameters. These results suggest that MetS is associated with an impairment of phospholipid metabolism in HDL, partially led by LCAT, and associated with obesity and underlying insulin resistance. This study proposes a candidate strategy to use integrated “omics” approaches to gain mechanistic insights into lipoprotein remodelling, thus deepening the knowledge regarding the molecular basis of the association between MetS and atherosclerosis. 相似文献
98.
Albert P. Doerschuk B. F. Daubert 《Journal of the American Oil Chemists' Society》1948,25(12):425-433
Summary Corn oil was subjected to a low-temperature solventfractionation process and separated into 19 glyceride fractions; the glyceride
structures of the fractions were calculated and added to obtain the glyceride structure of the oil. The experimentally obtained
glyceride structure was compared to the structures calculated according to the mono-acid triglyceride, random, even, and partial
random schemes and was found to agree most closely with the partial random system.
The generous financial assistance of the Corn Products Refining Company, Argo, Illinois, is gratefully acknowledged.
Contribution from the Department of Chemistry, University of Pittsburgh. 相似文献
99.
Summary A non-reducing disaccharide has been isolated from the kernels of tung (Aleurites fordi Hemsl.) and identified as sucrose. 相似文献
100.
P. Ganesh Kumar T. Aruldoss Albert VictoireP. Renukadevi D. Devaraj 《Expert systems with applications》2012,39(2):1811-1821
Knowledge gained through classification of microarray gene expression data is increasingly important as they are useful for phenotype classification of diseases. Different from black box methods, fuzzy expert system can produce interpretable classifier with knowledge expressed in terms of if-then rules and membership function. This paper proposes a novel Genetic Swarm Algorithm (GSA) for obtaining near optimal rule set and membership function tuning. Advanced and problem specific genetic operators are proposed to improve the convergence of GSA and classification accuracy. The performance of the proposed approach is evaluated using six gene expression data sets. From the simulation study it is found that the proposed approach generated a compact fuzzy system with high classification accuracy for all the data sets when compared with other approaches. 相似文献