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71.
Jelka Pleadin Manuela Zadravec Tina Lešić Nada Vahčić Jadranka Frece Mario Mitak 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(1):20-25
The aim of this study was to investigate ochratoxin A (OTA) and citrinin (CIT) co-occurrence in different unprocessed cereals (n = 189) originating from Croatia during a three-year investigation period (2014–2016) using validated enzyme immunoassay (ELISA) methods. CIT and OTA were determined in 49% and 7% of samples, respectively. Significantly higher (p < 0.05) overall mean concentrations were determined for CIT (66.8 ± 76.0 µg/kg) in comparison to OTA (5.2 ± 1.1 µg/kg). Based on the analysis of all investigated cereals, CIT was found about 15 times more frequently than OTA and in similarly (15-fold) higher concentrations, irrespective of the cultivation year. The results revealed a moderately positive correlation between OTA and CIT concentrations in maize (rs = 0.44) and wheat (rs = 0.59), whereas in barley and oat this correlation (p > 0.01) was not significant. 相似文献
72.
In vitro β‐Carotene Bioaccessibility and Lipid Digestion in Emulsions: Influence of Pectin Type and Degree of Methyl‐Esterification 下载免费PDF全文
Tina A.J. Verrijssen Stefanie Christiaens Sarah H.E. Verkempinck Jeroen Boeve Tara Grauwet Ann M. Van Loey Laura Salvia‐Trujillo Marc E. Hendrickx 《Journal of food science》2016,81(10):C2327-C2336
Citrus pectin (CP) and sugar beet pectin (SBP) were demethoxylated and fully characterized in terms of pectin properties in order to investigate the influence of the pectin degree of methyl‐esterification (DM) and the pectin type on the in vitro β‐carotene bioaccessibility and lipid digestion in emulsions. For the CP based emulsions containing β‐carotene enriched oil, water and pectin, the β‐carotene bioaccessibility, and lipid digestion were higher in the emulsions with pectin with a higher DM (57%; “CP57 emulsion”) compared to the emulsions with pectin with a lower DM (30%; “CP30 emulsion”) showing that the DM plays an important role. In contrast, in SBP‐based emulsions, nor β‐carotene bioaccessibility nor lipid digestion were dependent on pectin DM. Probably here, other pectin properties are more important factors. It was observed that β‐carotene bioaccessibility and lipid digestion were lower in the CP30 emulsion in comparison with the CP57, SBP32, and SBP58 emulsions. However, the β‐carotene bioaccessibility of CP57 emulsion was similar to that of the SBP emulsions, whereas the lipid digestion was not. It seems that pectin type and pectin DM (in case of CP) are determining which components can be incorporated into micelles. Because carotenoids and lipids have different structures and polarities, their incorporation may be different. This knowledge can be used to engineer targeted (digestive) functionalities in food products. If both high β‐carotene bioaccessibility and high lipid digestion are targeted, SBP emulsions are the best options. The CP57 emulsion can be chosen if high β‐carotene bioaccessibility but lower lipid digestion is desired. 相似文献
73.
74.
Pauline Kang Kathleen Watt Tina Chau Jenny Zhu Bruce J.W. Evans Helen Swarbrick 《Contact lens & anterior eye》2018,41(6):501-506
Purpose
To investigate the effects of short-term orthokeratology (OK) on accommodation and binocular visual function in young adults.Methods
Twenty-four myopes (18 to 38 years) were fitted with OK lenses in both eyes. Best corrected distance visual acuity (VA), subjective and objective refractions, corneal topography and a series of binocular vision tests were measured at baseline (BL) before lens wear and then repeated after 28 nights of OK. Data from 15 subjects who demonstrated successful OK lens fit are reported.Results
Corneal flattening and hyperopic shifts in spherical equivalent refractive error (all p?<?0.001) after 28 nights of OK indicated myopic correction. Improvement in best corrected distance VA was measured after OK (right eye p?=?0.021; left eye p?=?0.014). Although there was no significant change in mean distance and near phorias and stereoacuity scores after OK compared to BL, there was a significant reduction in standard deviation (SD) and range of data (distance p?=?0.01; near p?=?0.02; stereoacuity p?<?0.001). While there appeared to be an improvement in distance accommodative facility after OK, this failed to reach statistical significance (p?=?0.053). Furthermore, there was no change in AC/A gradients with ±1 D and ±2 D lenses after OK compared to BL.Conclusions
Binocular vision remained unchanged after OK, although variability of phoria and stereoacuity measures reduced. This suggests that OK improves or maintains accommodative and binocular vision function in young adult myopes who achieve good vision with OK. Myopes with phorias outside normal ranges and/or poor distance accommodative facility may benefit most with OK, in binocular and accommodative function. 相似文献75.
76.
A Modelling Approach for Handling Business Rules and Exceptions 总被引:1,自引:0,他引:1
77.
Hemicellulases used in the wheat separation process have resulted in better separation, purer fractions, increased plant capacity, reduced processing time etc. In order to further improve enzyme-treatment in the wheat separation process, monocomponent xylanases were evaluated. A laboratory viscosity model has been set up to evaluate the xylanases. The model showed good correlation (for a commercial hemicellulase preparation used for wheat separation) between viscosity of the wheat flour slurry and the sludge/supernatant ratio after centrifugation of the slurry. A xylanase (Novozyme 867) with excellent performance in the wheat separation process has been found. The xylanase has high activity towards soluble arabinoxylan and gives a rapid viscosity reduction of wheat flour slurries. The enzyme also has a moderate activity towards insoluble arabinoxylan, but due to the low molecular weight of the solubilized material this was not was found to contribute negatively to the enzymes' performance. The pH and temperature conditions in the wheat separation process were well within the active range of the enzyme. A pilot plant experiment showed improved yield of gluten and A-starch, with no apparent negative effect on the gluten quality. 相似文献
78.
Jimeng Sun Charalampos E. Tsourakakis Evan Hoke Christos Faloutsos Tina Eliassi-Rad 《Data mining and knowledge discovery》2008,17(1):111-128
Data stream values are often associated with multiple aspects. For example each value observed at a given time-stamp from environmental sensors may have an associated type (e.g., temperature,
humidity, etc.) as well as location. Time-stamp, type and location are the three aspects, which can be modeled using a tensor
(high-order array). However, the time aspect is special, with a natural ordering, and with successive time-ticks having usually
correlated values. Standard multiway analysis ignores this structure. To capture it, we propose 2 Heads Tensor Analysis (2-heads), which provides a qualitatively different treatment on time. Unlike most existing approaches that use a PCA-like
summarization scheme for all aspects, 2-heads treats the time aspect carefully. 2-heads combines the power of classic multilinear
analysis with wavelets, leading to a powerful mining tool. Furthermore, 2-heads has several other advantages as well: (a)
it can be computed incrementally in a streaming fashion, (b) it has a provable error guarantee and, (c) it achieves significant
compression ratio against competitors. Finally, we show experiments on real datasets, and we illustrate how 2-heads reveals
interesting trends in the data. This is an extended abstract of an article published in the Data Mining and Knowledge Discovery
journal. 相似文献
79.
Public clients have been identified as drivers of architectural, engineering and construction (AEC) industry change through their implementation of building information modelling (BIM). Yet, little is known of this implementation process and the associated challenges. This study aims to increase the understanding of what intra- and inter-organizational challenges that arise when a large Swedish public infrastructure client implements BIM to change the work practices of the actors in the Swedish AEC industry. The IT business value model allows for understanding the public client’s implementation of BIM as an IT-supported change process and for understanding the associated intra- and inter-organizational challenges. The findings show nine categories of intra- and inter-organizational challenges related to, for example, demanding BIM in procurement and creating incentives for BIM implementation. The findings show that intra-organizational challenges related to a top-down implementation of BIM, while inter-organizational challenges related to a bottom-up implementation. The impact of these challenges on the public client’s ability to drive AEC industry change by implementing BIM is discussed. The findings contribute with the client perspective to studies on BIM implementation and with an increased understanding of the challenges associated with implementing IT-supported change processes. 相似文献
80.