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排序方式: 共有1268条查询结果,搜索用时 15 毫秒
1.
Mirna Suárez-Quiroz Béatrice De Louise Oscar Gonzalez-Rios Michel Barel Bernard Guyot Sabine Schorr-Galindo & Joseph-Pierre Guiraud 《International Journal of Food Science & Technology》2005,40(6):605-611
Roasting coffee led to a drop in the ochratoxin A (OTA) concentration, as measured by the reference method, especially for dark type roasts. The way the beverage was prepared also affected the OTA content, which could paradoxically be higher than that of the initial roasted coffee. Assays on the thermal stability of pure OTA showed that it ought to be found in larger quantities in roasted coffee. This suggested that OTA was masked by reactions with the substrate during roasting. The absence of OTA in green coffee is therefore the best guarantee of safety. 相似文献
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Nocturnal intragastric feeding has been shown to be an effective means to improve clinical and biochemical features in glycogen
storage disease type I (GSD-I). In this study, we investigated the fatty acid patterns in a whole plasma and in circulating
lipoproteins in patients on this therapy. The results demonstrated massive concentration of total fatty acids coupled with
higher levels of triglycerides, free cholesterol, cholesterol ester and phospholipids. This hyperlipidemia involved all fatty
acids without distinction of carbon or bond numbers. However, the increase was more pronounced for saturated than polyunsaturated
fatty acids, as was demonstrated by the ratios of both oleic acid to linoleic acid (1.91±0.40 vs 0.80±0.09 in controls) and
of ω3+ω6 to ω9 fatty acid families (0.92±0.11 vs 1.66±0.08 in controls). The fatty acid patterns in very low (VLDL), low (LDL)
and high (HDL) density lipoprotein showed substantial differences in composition, reflecting an association between an abnormal
lipoprotein pattern and essential fatty acid deficiency. Furthermore, GSD-I patients exhibited a significant increase in VLDL
(17±2 vs 47±7 mg/dl) and LDL cholesterol (124±7 vs 206±24 mg/dl), coupled with a decrease in HDL cholesterol (49±4 vs 28±3
mg/dl). These data documenting high LDL cholesterol and low HDL cholesterol associated with an increased concentration and
proportion of saturated fatty acids suggest that GSD-I patients on nocturnal intragastric feeding are at high risk for atherosclerosis
and its complications. 相似文献
5.
Assay of aflatoxin in peanuts and peanut products using acetone-hexane-water for extraction 总被引:3,自引:0,他引:3
J. A. Robertson Jr. Louise S. Lee Alva F. Cucullu L. A. Goldblatt 《Journal of the American Oil Chemists' Society》1965,42(6):467-471
A quantitative method is described for the assay of aflatoxin in peanut products. The procedure involves extraction of aflatoxin
from the sample with a homogeneous acetone-hexane-water solvent mixture followed by purification of the extract by phasic
extraction of the aflatoxin with aqueous sodium chloride and then with chloroform. The purified chloroform extract is analyzed
by thin-layer chromatography by comparison of the intensity of fluorescence of any aflatoxin with the intensity of a known
standard. The aflatoxin analyses of peanuts were found to be very variable due to sampling, and this variability has been
greatly reduced by finely grinding and thoroughly mixing 2 kg of the sample before removal of an aliquot for assay. The method
is sensitive to approximately 2 parts per billion.
Honorable mention, Bond Award competition. Presented at AOCS Meeting, Chicago, Illinois, October, 1964.
So. Reg. Res. Lab., New Orleans, Louisiana, one of the laboratories of the So. Utiliz. Res. and Dev. Div., ARS, USDA. 相似文献
6.
Louise A. Dennis Michael Fisher Matthew P. Webster Rafael H. Bordini 《Automated Software Engineering》2012,19(1):5-63
In this paper we describe a verification system for multi-agent programs. This is the first comprehensive approach to the verification of programs developed using programming languages based on the BDI (belief-desire-intention)
model of agency. In particular, we have developed a specific layer of abstraction, sitting between the underlying verification
system and the agent programming language, that maps the semantics of agent programs into the relevant model-checking framework.
Crucially, this abstraction layer is both flexible and extensible; not only can a variety of different agent programming languages
be implemented and verified, but even heterogeneous multi-agent programs can be captured semantically. In addition to describing this layer, and the semantic mapping inherent
within it, we describe how the underlying model-checker is driven and how agent properties are checked. We also present several
examples showing how the system can be used. As this is the first system of its kind, it is relatively slow, so we also indicate
further work that needs to be tackled to improve performance. 相似文献
7.
Anna N. Boss Abhirup Banerjee Michail Mamalakis Surajit Ray Andrew J. Swift Craig Wilkie Joseph W. Fanstone Bart Vorselaars Joby Cole Simonne Weeks Louise S. Mackenzie 《International journal of molecular sciences》2022,23(13)
Acute kidney injury (AKI) is a prevalent complication in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive inpatients, which is linked to an increased mortality rate compared to patients without AKI. Here we analysed the difference in kidney blood biomarkers in SARS-CoV-2 positive patients with non-fatal or fatal outcome, in order to develop a mortality prediction model for hospitalised SARS-CoV-2 positive patients. A retrospective cohort study including data from suspected SARS-CoV-2 positive patients admitted to a large National Health Service (NHS) Foundation Trust hospital in the Yorkshire and Humber regions, United Kingdom, between 1 March 2020 and 30 August 2020. Hospitalised adult patients (aged ≥ 18 years) with at least one confirmed positive RT-PCR test for SARS-CoV-2 and blood tests of kidney biomarkers within 36 h of the RT-PCR test were included. The main outcome measure was 90-day in-hospital mortality in SARS-CoV-2 infected patients. The logistic regression and random forest (RF) models incorporated six predictors including three routine kidney function tests (sodium, urea; creatinine only in RF), along with age, sex, and ethnicity. The mortality prediction performance of the logistic regression model achieved an area under receiver operating characteristic (AUROC) curve of 0.772 in the test dataset (95% CI: 0.694–0.823), while the RF model attained the AUROC of 0.820 in the same test cohort (95% CI: 0.740–0.870). The resulting validated prediction model is the first to focus on kidney biomarkers specifically on in-hospital mortality over a 90-day period. 相似文献
8.
Le Hegarat-Mascle S. Bloch I. Vidal-Madjar D. 《Geoscience and Remote Sensing, IEEE Transactions on》1997,35(4):1018-1031
The aim of this paper is to show that Dempster-Shafer evidence theory may be successfully applied to unsupervised classification in multisource remote sensing. Dempster-Shafer formulation allows for consideration of unions of classes, and to represent both imprecision and uncertainty, through the definition of belief and plausibility functions. These two functions, derived from mass function, are generally chosen in a supervised way. In this paper, the authors describe an unsupervised method, based on the comparison of monosource classification results, to select the classes necessary for Dempster-Shafer evidence combination and to define their mass functions. Data fusion is then performed, discarding invalid clusters (e.g. corresponding to conflicting information) thank to an iterative process. Unsupervised multisource classification algorithm is applied to MAC-Europe'91 multisensor airborne campaign data collected over the Orgeval French site. Classification results using different combinations of sensors (TMS and AirSAR) or wavelengths (L- and C-bands) are compared. Performance of data fusion is evaluated in terms of identification of land cover types. The best results are obtained when all three data sets are used. Furthermore, some other combinations of data are tried, and their ability to discriminate between the different land cover types is quantified 相似文献
9.
Mahiar M. Hamedi Victoria E. Campbell Philipp Rothemund Firat Güder Dionysios C. Christodouleas Jean‐Francis Bloch George M. Whitesides 《Advanced functional materials》2016,26(15):2446-2453
This paper describes the design and fabrication of electrically controlled paper actuators that operate based on the dimensional changes that occur in paper when the moisture absorbed on the surface of the cellulose fibers changes. These actuators are called “Hygroexpansive Electrothermal Paper Actuators” (HEPAs). The actuators are made from paper, conducting polymer, and adhesive tape. They are lightweight, inexpensive, and can be fabricated using simple printing techniques. The central element of the HEPAs is a porous conducting path (used to provide electrothermal heating) that changes the moisture content of the paper and causes actuation. This conducting path is made by embedding a conducting polymer (PEDOT:PSS) within the paper, and thus making a paper/polymer composite that retains the porosity and hydrophilicity of paper. Different types of HEPAs (straight, precurved, and creased) achieved different types of motions (e.g., bending motion, accordion type motion). A theoretical model for their behavior is proposed. These actuators have been used for the manipulation of liquids and for the fabrication of an optical shutter. 相似文献
10.
Partial Reconfiguration (PR) is a method for Field Programmable Gate Array (FPGA) designs which allows multiple applications
to time-share a portion of an FPGA while the rest of the device continues to operate unaffected. Using this strategy, the
physical layer processing architecture in Software Defined Radio (SDR) systems can benefit from reduced complexity and increased
design flexibility, as different waveform applications can be grouped into one part of a single FPGA. Waveform switching often
means not only changing functionality, but also changing the FPGA clock frequency. However, that is beyond the current functionality
of PR processes as the clock components (such as Digital Clock Managers (DCMs)) are excluded from the process of partial reconfiguration.
In this paper, we present a novel architecture that combines another reconfigurable technology, Dynamic Reconfigurable Port
(DRP), with PR based on a single FPGA in order to dynamically change both functionality and also the clock frequency. The
architecture is demonstrated to reduce hardware utilization significantly compared with standard, static FPGA design. 相似文献