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51.
Traditionally Processed Beverages in Africa: A Review of the Mycotoxin Occurrence Patterns and Exposure Assessment 下载免费PDF全文
Chibundu N. Ezekiel Kolawole I. Ayeni Jane M. Misihairabgwi Yinka M. Somorin Ihuoma E. Chibuzor‐Onyema Oluwawapelumi A. Oyedele Wilfred A. Abia Michael Sulyok Gordon S. Shephard Rudolf Krska 《Comprehensive Reviews in Food Science and Food Safety》2018,17(2):334-351
African traditional beverages are widely consumed food‐grade liquids processed from single or mixed grains (mostly cereals) by simple food processing techniques, of which fermentation tops the list. These beverages are very diverse in composition and nutritional value and are specific to different cultures and countries. The grains from which home‐processed traditional beverages are made across Africa are often heavily contaminated with multiple mycotoxins due to poor agricultural, handling, and storage practices that characterize the region. In the literature, there are many reports on the spectrum and quantities of mycotoxins in crops utilized in traditional beverage processing, however, few studies have analyzed mycotoxins in the beverages themselves. The available reports on mycotoxins in African traditional beverages are mainly centered on the finished products with little information on the process chain (raw material to final product), fate of the different mycotoxins during processing, and exposure estimates for consumers. Regulations targeting these local beverages are not in place despite the heavy occurrence of mycotoxins in their raw materials and the high consumption levels of the products in many homes. This paper therefore comprehensively discusses for the 1st time the available data on the wide variety of African traditional beverages, the mycotoxins that contaminate the beverages and their raw materials, exposure estimates, and possible consequent effects. Mycotoxin control options and future directions for mycotoxin research in beverage production are also highlighted. 相似文献
52.
Moos Rudolf H.; Brennan Penny L.; Fondacaro Mark R.; Moos Bernice S. 《Canadian Metallurgical Quarterly》1992,7(4):653b
Reports a clarification in the article by R. H. Moos et al (Psychology and Aging, 1990[Mar], Vol 5[1], 31–40). The authors wish to note that research reported in the article by P. L. Brennan and R. H. Moos (see record 1991-10154-001) was based on the sample used in the research reported by Moos et al and that this information was inadvertently deleted in the Brennan and Moos article. (The following abstract of the article by Moos et al originally appeared in PA, Vol 77:14961.) The Coping Responses Inventory (CRI) was used to study coping among older problem and nonproblem drinkers. The CRI organizes coping efforts according to their focus (approach or avoidance) and method (cognitive or behavioral). Compared with nonproblem drinkers, older problem drinkers were more likely to use cognitive and behavioral avoidance responses to manage life stressors. Problem drinkers who experienced more negative life events and more severe stressors used both more approach and more avoidance coping. Those who had more financial and social resources relied more on approach and less on avoidance coping. Problem drinkers who relied more on avoidance coping tended to have more drinking problems and to report more depression and physical symptoms and less self-confidence. Positive reappraisal was associated with less depression and more self-confidence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Pter P. Lakatos Dvid rpd Kardi Anna Rita Galambos Nariman Essmat Kornl Kirly Rudolf Laufer Orsolya Geda Zoltn S. Zdori Tams Tbi Mahmoud Al-Khrasani va Szk 《International journal of molecular sciences》2022,23(17)
Current treatment approaches to manage neuropathic pain have a slow onset and their use is largely hampered by side-effects, thus there is a significant need for finding new medications. Tolperisone, a centrally acting muscle relaxant with a favorable side effect profile, has been reported to affect ion channels, which are targets for current first-line medications in neuropathic pain. Our aim was to explore its antinociceptive potency in rats developing neuropathic pain evoked by partial sciatic nerve ligation and the mechanisms involved. Acute oral tolperisone restores both the decreased paw pressure threshold and the elevated glutamate level in cerebrospinal fluid in neuropathic rats. These effects were comparable to those of pregabalin, a first-line medication in neuropathy. Tolperisone also inhibits release of glutamate from rat brain synaptosomes primarily by blockade of voltage-dependent sodium channels, although inhibition of calcium channels may also be involved at higher concentrations. However, pregabalin fails to affect glutamate release under our present conditions, indicating a different mechanism of action. These results lay the foundation of the avenue for repurposing tolperisone as an analgesic drug to relieve neuropathic pain. 相似文献
54.
The effectiveness of the reactive extrusion technique was investigated for poly(ethylene terephthalate) to promote the concept of closed‐loop recycling, that is, the reuse of waste material in the initial application. More specifically, a chain‐extender system, consisting of pyromellitic dianhydride, polyol, and a catalyst, was employed, and its efficiency regarding the improvement of the recyclate quality was evaluated. Accordingly, rheological and thermal characterizations were performed and used as criteria of the modification induced in the polymer molecular structure during processing due to the counteracting degradation and chain‐extension reactions. In particular, the molecular weight, related to intrinsic viscosity and melt flow rate measurements, of modified poly(ethylene terephthalate) samples was found to increase with the additive content. Simultaneously, a decrease in the crystallinity was observed, attributed to the branching effect of the chain extender, which restricted the ability of the macromolecules to organize in the crystal structure. Beyond a critical concentration of the additive system, the molecular weight of the treated samples started to decrease again, and this was accompanied by a small increase in the crystallinity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1671–1678, 2007 相似文献
55.
The aim of this work was to compare the microstructures of two high noble experimental Au-Pt alloys with similar composition
with their corrosion and biocompatibility in vitro. We showed that Au-Pt II alloy, composed of 87.3 wt.% Au, 9.9 wt.% Pt,
1.7 wt.% Zn and 0.5 wt.% Ir + Rh + In, although possessing better mechanical properties than the Au-Pt I alloy (86.9 wt.%
Au, 10.4 wt.% Pt, 1.5 wt.% Zn and 0.5 wt.% Ir + Rh + In), exerted higher adverse effects on the viability of L929 cells and
the suppression of rat thymocyte functions, such as proliferation activity, the production of Interleukin-2 (IL-2), expression
of IL-2 receptor and activation — induced apoptosis after stimulation of the cells with Concanavalin-A. These results correlated
with the higher release of Zn ions in the culture medium. As Zn2+, at the concentrations which were detected in the alloy’s culture media, showed a lesser cytotoxic effect than the Au-Pt
conditioning media, we concluded that Zn is probably not the only element responsible for alloy cytotoxicity. Microstructural
characterization of the alloys, performed by means of scanning electron microscopy in addition to energy dispersive X-ray
and X-ray diffraction analyses, showed that Au-Pt I is a two-phase alloy containing a dominant Au-rich α1 phase and a minor Pt-rich α2 phase. On the other hand, the Au-Pt II alloy additionally contained three minor phases: AuZn3, Pt3Zn and Au1.4Zn0.52. The highest content of Zn was identified in the Pt3Zn phase. After conditioning, the Pt3Zn and AuZn3 phases disappeared, suggesting that they are predominantly responsible for Zn loss, lower corrosion stability and subsequent
lower biocompatibility of the Au-Pt II alloy. 相似文献
56.
André Dias Lukas Gorzelniak Rudolf A. Jörres Rainald Fischer Gunnar Hartvigsen Alexander Horsch 《Pervasive and Mobile Computing》2012,8(6):837-844
Physical Activity (PA) plays an important role in the health and quality of life of cystic fibrosis (CF) patients, but little is known about their PA in daily living. With the use of accelerometers it is now possible to monitor activity profiles in detail. The goals of this study are to assess feasibility and acceptance of a longer-term use of accelerometers in daily living in CF patients, study the possibility of detecting changes in PA in relation to the patients’ clinical state and compare the findings between a CF and an age-matched healthy control group. We asked 15 CF patients to wear two accelerometers for 21 days and fill in a diary. Ten of them (age 21 to 40, mean 29.5 years) participated and delivered data that could be evaluated. We also recruited 10 age-matched control subjects. Data was processed for calculating usage time and features extracted to construct models of activity. The younger patients, particularly females, were concerned with fashion and style and considered wearing the sensors a challenge. Overall, the compliance of patients with CF seemed to be lower than reported for elder subjects in the literature. Time-series analysis of the data indicated characteristic patterns of PA over time, provided that data pre-processing and noise-filtering had been optimized. Further studies have to assess whether the continuous recording of PA yields additional clinical information in CF and in particular, whether it is possible to detect or even predict exacerbations in patients with CF or other diseases. 相似文献
57.
Thomas Beer Tobias Meisen Rudolf Reinhard Sergey Konovalov Daniel Schilberg Sabina Jeschke Torsten Kuhlen Christian Bischof 《Production Engineering》2011,5(4):383-391
Computational simulations are used for the optimization of production processes in order to significantly reduce the need
for costly experimental optimization approaches. Yet individual simulations can rarely describe more than a single production
step. A set of simulations has to be coupled to each other to form a contiguous representation of a process chain. Eventually,
simulated results have to be analyzed by domain experts to gather insight from the preformed computations. In this paper,
we propose an IT infrastructure and software tools that aim at a rather non-intrusive way of coupling resources and domain
expert’s knowledge to enable the collaborative setup, execution and analysis of distributed simulation chains. We illustrate
the approach in the domain of materials processing. Beyond means originating from the domain of GRID computing for resource
management, a data integration component assures semantic data integrity between the simulation steps and stores simulation
data in an application independent way. Thus, we can transform this data into native formats for each simulation tool, and
finally into a format that allows for contiguous visualizations and an intuitive, comprehensive analysis of complete simulated
process chains. 相似文献
58.
Thomas Anung Basuki Antonio Cerone Andreas Griesmayer Rudolf Schlatte 《Formal Aspects of Computing》2009,21(6):571-588
This article describes a framework to formally model and analyse human behaviour. This is shown by a simple case study of
a chocolate vending machine, which represents many aspects of human behaviour. The case study is modelled and analysed using
the Maude rewrite system. This work extends a previous work by Basuki which attempts to model interactions between human and
machine and analyse the possibility of errors occurring in the interactions. By redesigning the interface, it can be shown
that certain kinds of error can be avoided for some users. This article overcomes the limitation of Basuki’s approach by incorporating
many aspects of user behaviour into a single user model, and introduces a more natural approach to model human–computer interaction. 相似文献
59.
Rudolf Herzog 《?sterreichische Wasser- und Abfallwirtschaft》2009,61(11-12):a30-a33
60.
Lütke-Eversloh T Fischer A Remminghorst U Kawada J Marchessault RH Bögershausen A Kalwei M Eckert H Reichelt R Liu SJ Steinbüchel A 《Nature materials》2002,1(4):236-240
The development of non-petrochemical sources for the plastics industry continues to progress as large multinationals focus on renewable resources to replace fossil carbon. Many bacteria are known to accumulate polyoxoesters as water-insoluble granules in the cytoplasm. The thermoplastic and/or elastomeric behaviour of these biodegradable polymers holds promise for the development of various technological applications. Here, we report the synthesis and characterization of microbial polythioesters (PTEs), a novel class of biopolymers of general technological relevance. Biosynthesis of PTE homopolymers was achieved using a recombinant strain of Escherichia coli that expressed a non-natural pathway consisting of a butyrate kinase, a phosphotransbutyrylase, and a PHA synthase. Different homopolymers were produced, consisting of either 3-mercaptopropionate, 3-mercaptobutyrate, or 3-mercaptovalerate repeating units, if the respective mercaptoalkanoic acids were provided as precursor substrates to the fermentative process. The PTEs contributed up to 30% (w/w) of the cellular dry weight and were identified as hydrophobic inclusions in the cytoplasm. The chemical and stereochemical homogeneity of the purified PTEs were identified by different methods, and the estimated physical properties were compared to the oxypolyester equivalents, revealing low crystalline order and, for the poly(3-mercaptopropionate) improved thermal stability. The ability to produce PTEs through a biosynthetic route opens up new avenues in the field of biomaterials. 相似文献