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101.
Dyes are a category of substances capable of inducing allergic contact dermatitis found in a variety of foods, drugs, textiles, cosmetics, and hair dyes. This study tested 33 dyes in guinea pigs using a modified Buehler and Klecak method for open epicutaneous testing. The dyes were tested at an induction concentration of 10% and challenge concentrations of 10.0%, 5.0%, and 2.5%. Nine of the 33 dyes tested produced positive allergic reactions in the guinea pig model (2-amino-4-nitrophenol, 2-amino-5-nitrophenol, acid yellow 23, acid orange 3, basic black 3, basic orange 1, disperse orange 3, solvent black 27, and solvent black 34). When eight of the nine positive dyes were retested using a 1% induction concentration, five dyes produced allergic contact dermatitis at a 1% challenge concentration (2-amino-4-nitrophenol, 2-amino-5-nitrophenol, acid yellow 23, disperse orange 3, and solvent black 34), two at a 0.5% challenge concentration (2-amino-5-nitrophenol and solvent black 34), and one at a 0.25% challenge concentration (2-amino-5-nitrophenol). DNCB at a 0.5% induction/challenge concentration was used as a positive control. With the exception of disperse orange 3 and acid yellow 23, the seven additional dyes that elicited positive allergic reactions in the guinea pig model have not been previously reported.  相似文献   
102.
从南斯拉夫到塞尔维亚,无论是二战后的铁托时代,还是糟糕的巴尔干战争,共产主义的黄金时代从未在这里出现过,但一座以"黄金时代的共产主义"为设计灵感的超市概念店却在这里开业了。超市的原址是贝尔格莱德第一家折扣超市的原址,这样的历史给后来者留下的只有鞭策。  相似文献   
103.
An HPLC method was developed for the quantitative determination of 2,4,6-triiodoresorcinol (I3R), 2-(2',4'-dihydroxy-3',5'-diiodobenzoyl)benzoic acid, resorcinol, phthalic acid, and sodium iodide in the colour additive FD&C Red No. 3 (erythrosine) (R3). Due to the fast decomposition of I3R in aqueous solutions, the dye portions analysed were dissolved in methanol and the determinations were performed in the freshly-made solutions. The HPLC method is rapid (50 min total analysis cycle, ∼16 min to detect I3R and the other intermediates), simple to implement, and generates only small amounts of solvent waste. It was found to be applicable for use in routine batch-certification as shown by the analysis of test portions from 24 lots of R3 submitted for US-certification by domestic and foreign manufacturers during the past three years.  相似文献   
104.
Describes an outpatient relapse prevention group therapy program for child molesters. 50 men have completed the initial phase of the program thus far. Based on the assumption that the individual can learn to recognize risk situations and exert control over potentially harmful urges, the program stresses support, self-help, and education. Considerable time is spent helping the men identify risky mood states, since it is assumed that intervention is best carried out at the feeling stage, before the pedophile forms and then enacts a plan. Ultimately, it is hoped that these men can stop their impulsive and harmful acts through the development of an empathic understanding of the perspective of the other. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Collision cross sections in both helium and nitrogen gases were measured directly using a drift cell with RF ion confinement inserted within a quadrupole/ion mobility/time-of-flight hybrid mass spectrometer (Waters Synapt HDMS, Manchester, U.K.). Collision cross sections for a large set of denatured peptide, denatured protein, native-like protein, and native-like protein complex ions are reported here, forming a database of collision cross sections that spans over 2 orders of magnitude. The average effective density of the native-like ions is 0.6 g cm(-3), which is significantly lower than that for the solvent-excluded regions of proteins and suggests that these ions can retain significant memory of their solution-phase structures rather than collapse to globular structures. Because the measurements are acquired using an instrument that mimics the geometry of the commercial Synapt HDMS instrument, this database enables the determination of highly accurate collision cross sections from traveling-wave ion mobility data through the use of calibration standards with similar masses and mobilities. Errors in traveling-wave collision cross sections determined for native-like protein complexes calibrated using other native-like protein complexes are significantly less than those calibrated using denatured proteins. This database indicates that collision cross sections in both helium and nitrogen gases can be well-correlated for larger biomolecular ions, but non-correlated differences for smaller ions can be more significant. These results enable the generation of more accurate three-dimensional models of protein and other biomolecular complexes using gas-phase structural biology techniques.  相似文献   
106.
In this paper a model based on population biology is proposed in order to investigate the evolution of human resources (men and women) in science and technology as a share of labor market as well as the dynamics of their gap. An analytical and a simulation method using the Artificial Bee Colony optimization algorithm are described and used for the determination of the proposed model parameters. The presented model is applied to three case studies; Greece, Portugal and Europe-27.3 The accuracy of the obtained results is confirmed through comparison with actual data. In addition, the model can also be used to accurately forecast future trends. It is illustrated that the gender gap is continuously decreasing, while in the last years, women seem to outperform men in the field of science and technology. The estimation and forecasting ability of the model can be used as an extremely valuable tool for decision and policy makers.  相似文献   
107.
The user experience of current P2P Personal and Social networking systems does not meet the usability needs of the technically naïve users. This is the motivation behind MyNet, a P2P platform that enables non-expert users to easily organize their resources and share them in their immediate social neighborhood. In this paper, we present our experience following a user-centered approach in designing MyNet: using real-world metaphors in the core system, leveraging NFC-based touch to mirror human behavior models, and involving actual users in the design process. The results of our 50-user usability evaluation are also presented in detail.  相似文献   
108.
From desktops to Web sites, E-mail to call centres, customer relationship to supply chain management, businesses are beginning to invest in the next generation of IT. The explosion of E-commerce and the transformation of mobile phones to multi-functional devices will drive that trend. This article looks at how technological advances, convergence and consolidation within the marketplace are changing the shape of IT transactions. It also considers some of the legal challenges this raises for IT customers and suppliers.  相似文献   
109.
The production of nanofibers of bioactive glass by laser spinning is reported. The technique yields a great quantity of free‐standing fibers in the form of a mesh of disordered intertwined fibers. The method does not rely on chemical processing and does not need any chemical additive. It involves melting of a precursor material with tailored composition, which makes it possible to produce nanofibers from materials with which conventional melt drawing techniques cannot be used. Herein, the production of 45S5 Bioglass nanofibers is reported for the first time. The process is very fast (nanofibers of several centimeters are grown in a fraction of a second), without the necessity of post heat treatments, and no devitrification is observed as a result of the laser‐spinning process. The morphology, composition, and structure of the nanofibers are characterized and an assessment of their bioactivity is carried out by immersion in simulated body fluid. This technique provides a method for the rapid production of dense glass nanofibers that can be employed as bioactive nanocomposite reinforcement, as a synthetic bone graft to replace missing bone, or to produce 3D structures for use as scaffolds for bone‐tissue engineering.  相似文献   
110.
This paper is using a fuzzy classification system for human reliability analysis in order to calculate the probability of erroneous actions according to CREAM in specific contexts e.g. maintenance tasks, in-field actions or control room operations in the running of a chemical plant. The complexities of such a system as well as the appropriate actions that have to be taken into consideration by the developers are analysed in detail. CREAM methodology has been selected among the most known and used methods for Human Reliability Analysis not only for being well-structured and precise, but also because it fits better in the general structure of the fuzzy logic. The first results from the application of the model are very promising and in accordance with CREAM. The numerical values produced by the model can be further used in the ‘classical’ risk assessment methods, such as event trees and fault trees, in order to calculate the overall occurrence frequency of a particular hazardous event. This is a pilot application that demonstrates the successful ‘translation’ of CREAM into a fuzzy logic model. However, the same model could be extended to cover also other industrial fields, like aviation technology and maritime transports.  相似文献   
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