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51.
Branko Deljanin Dusan Simic Alexander Zaitsev John Chapman Inga Dobrinets Annette Widemann Nicholas Del Re Tara Middleton Elena Deljanin Andrea De Stefano 《Diamond and Related Materials》2008,17(7-10):1169-1178
One of the commercial challenges today in the gem industry is to quickly identify the origin of color in pink diamonds — natural, treated and synthetic by use of standard and advanced gemological instruments.An analytical technique that is used by many gem labs involves UV fluorescence. The principle factors in the technique are the excitation wavelengths and the emission spectra. No systematic study of fluorescence of pink natural diamonds, pink treated and pink synthetic diamonds has been undertaken. This study is mainly focused on using fluorescence techniques to characterize pink diamonds and to compile a reference library of emission spectra. Longwave (LW) and shortwave (SW) fluorescence of 365, 254 and 220 nm illumination were used in a custom built microscope with a fluorescence camera to record images and a spectrometer to record spectral data with which to establish a correlation with the cause of color.Other advanced instruments (CL imaging, UV–VIS–NIR, FTIR, PL spectroscopy and electrical conductance) were used to establish additional criteria for distinguishing natural, treated and synthetic pink diamonds and to find a correlation with the “EGL USA CIS (Cross-reference Identification System) fluorescence method”. 相似文献
52.
53.
Meckelein Barbara; Nikiforov Theo; Clemen Annette; Appelhans Heribert 《Protein engineering, design & selection : PEDS》1990,3(3):215-220
Human mucus proteinase inhibitor (MPI) consists of 107 aminoacids arranged in two domains showing high homology to eachother. This protein is an inhibitor of different serine proteinasesincluding trypsin, chymotrypsin, leukocyte elastase and cathepsinG. On the basis of sequence comparisons it has been suggestedthat the first domain inhibits trypsin, whereas the second onewas thought to be active against chymotrypsin and elastase.To prove the location of the different inhibitory activitiesgene fragments for both domains have been cloned separatelyand expressed in Escherichia coli. Inhibition assays with theisolated recombinant domains showed that the second domain isactive against chymotrypsin, neutrophil elastase and trypsin,whereas for the first domain only a weak activity against trypsincould be detected. These results suggest that the inhibitoryactivities of the native molecule towards these three proteinasesare all located in the second domain. 相似文献
54.
Berninghaus Siegfried K.; Güth Werner; Kirstein Annette 《Canadian Metallurgical Quarterly》2008,1(1):33
Systematic experiments with distribution games have shown that participants are strongly motivated by considerations of fairness and efficiency. This evidence, however, results mainly from experimental designs in which money is shared directly. Furthermore, fairness does not necessarily require equal payoffs, but may instead require equal allocations. We investigate experimentally the frame dependency of reaching equal (commodity or payoff) splits by systematically comparing net-trade proposals and payoff proposals for the same exchange economy with two traders, two commodities and multi-period negotiations. We can confirm the hypothesis that asking participants to allocate money directly, rather than more naturally via the allocation of commodities, is far from being harmless and likely overstates fairness and efficiency concerns. What is more, we try to apply the insights gained from our experiment to management problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Selecting Agricultural Best Management Practices for Water Conservation and Quality Improvements Using Atanassov’s Intuitionistic Fuzzy Sets 总被引:2,自引:0,他引:2
Improper agricultural practices can affect ground water through leaching, surface water through runoff, algae infestations,
deforestation, and air quality through burning operations and ammonia emissions. These effects may be mitigated through the
institution of best management practices. The utility of best management practices (BMPs) is recognized and being actively
promoted by agricultural agencies; however, identifying a set of mandatory BMPs is inappropriate given variations between
climactic, demographic and geographic regions as well as differences in farming practices. In this study, a multi-criteria
decision making model based on Attanassov’s Intuitionistic Fuzzy Set (A-IFS) theory is introduced and its utility to rank
agricultural best management practices is illustrated using a case-study from South Texas. Implementation of the A-IFS MCDM
method to the South Texas region resulted in “irrigation scheduling” being ranked as the most preferred alternative, while
“brush control/management” was the least preferred. The A-IFS MCDM approach was particularly suitable for prioritizing and
ranking agricultural best management practices because decision makers often tend to have both likes and dislikes with regards
to specific BMPs and for a given evaluation attribute. Not only does the A-IFS MCDM method provide a single composite score
to rank the BMP alternatives, but the output of the A-IFS MCDM method also includes upper and lower bounds that help identify
the uncertainties in the decision making process. 相似文献
56.
Ulrich Reffle Annette Gotscharek Christoph Ringlstetter Klaus U. Schulz 《International Journal on Document Analysis and Recognition》2009,12(3):165-174
The detection and correction of false friends—also called real-word errors—is a notoriously difficult problem. On realistic
data, the break-even point for automatic correction so far could not be reached: the number of additional infelicitous corrections
outnumbered the useful corrections. We present a new approach where we first compute a profile of the error channel for the
given text. During the correction process, the profile (1) helps to restrict attention to a small set of “suspicious” lexical
tokens of the input text where it is “plausible” to assume that the token represents a false friend. In this way, recognition
of false friends is improved. Furthermore, the profile (2) helps to isolate the “most promising” correction suggestion for
“suspicious” tokens. Using a conventional word trigram statistics for disambiguation we obtain a correction method that can
be successfully applied to unrestricted text. In experiments for OCR documents, we show significant accuracy gains by fully
automatic correction of false friends. 相似文献
57.
Assessing landscape preferences: a visual choice experiment in the agricultural region of Märkische Schweiz,Germany 总被引:1,自引:0,他引:1
Kati Häfner Ingo Zasada Boris T. van Zanten Fabrizio Ungaro Mark Koetse Annette Piorr 《Landscape Research》2018,43(6):846-861
Natural amenities and the aesthetic value of agricultural landscapes are important territorial assets for improving rural tourism and the quality of the living environment. To identify which characteristics shape the visual quality of a landscape, a stated-preference survey was conducted (N = 200) using photorealistic landscape visualisations of four different landscape attributes (point green elements, linear green elements, crop diversity and presence of livestock). We estimated respondents’ preferences for landscape attributes, examined the extent of agreement among respondents and identified socio-economic factors influencing their responses. Results revealed that point elements had the highest general preference. About 70% of respondents preferred diverse and highly structured landscapes, while about 30% of respondents had opposing preferences. Preferences were also found to be dependent on the individual’s sociocultural background, such as their level of education, gender or age. These results can help to improve the multi-objective targeting of policies by including an aesthetic value perspective. 相似文献
58.
Annette Kolb-M?urer Matthias Goebeler Mathias M?urer 《International journal of molecular sciences》2015,16(7):14951-14960
Interferons are widely used platform therapies as disease-modifying treatment of patients with multiple sclerosis. Although interferons are usually safe and well tolerated, they frequently cause dermatological side effects. Here, we present a multiple sclerosis (MS) patient treated with interferon-β who developed new-onset psoriasis. Both her MS as well as her psoriasis finally responded to treatment with fumarates. This case illustrates that interferons not only cause local but also systemic adverse events of the skin. These systemic side effects might indicate that the Th17/IL-17 axis plays a prominent role in the immunopathogenesis of this individual case and that the autoimmune process might be deteriorated by further administration of interferons. In conclusion, we think that neurologists should be aware of systemic cutaneous side effects and have a closer look on interferon-associated skin lesions. Detection of psoriasiform lesions might indicate that interferons are probably not beneficial in the individual situation. We suggest that skin lesions may serve as biomarkers to allocate MS patients to adequate disease-modifying drugs. 相似文献
59.
The harlequin ladybird Harmonia axyridis (Coleoptera: Coccinellidae) is a polyphagous predatory beetle native to Central and Eastern Asia. Since 2007 it has established all over Central Europe. In order to elucidate which defense strategy is responsible for its high resistance to diseases, we tested hemolymph as well as eleven main components of the headspace of H. axyridis for antimicrobial activity against Gram-positive (Bacillus subtilis, B. thuringiensis ssp. tenebrionis, Micrococcus luteus) and Gram-negative bacteria (Escherichia coli) and yeast (Saccharomyces cerevisiae). While three of the volatile compounds weakly reduced the growth of microorganisms, hemolymph of adults and larvae of H. axyridis strongly inhibited the growth of Gram-positive and Gram-negative bacteria as well as yeast. Furthermore, we compared the antimicrobial activity in the hemolymph of H. axyridis and Coccinella septempunctata. Antimicrobial activity in H. axyridis was about a thousand times higher compared to hemolymph from C. septempunctata. In contrast to C. septempunctata, the antimicrobial activity in H. axyridis was present without prior challenge. Minimal inhibitory concentration (MIC) of the hemolymph of H. axyridis was lowest against E. coli and yeast followed by B. subtilis, and was highest against entomopathogenic B. thuringiensis ssp. tenebrionidae. Furthermore, MIC values of the hemolymph obtained from live beetles were significantly lower than from frozen insects. This suggests that the active antimicrobial compound is affected by freezing and subsequent thawing of the beetles. Potential implications of our findings for the competitive advantages of H. axyridis over C. septempunctata are discussed. 相似文献
60.
In the testing of ocean wave energy devices, the demand for a portable and robust data acquisition and electrical loading system has become apparent. This paper investigates the development of a 30 kW inclusive system combining loading capabilities, real-time power analysis, and data acquisition for the testing of deployed ocean wave energy devices. Hardware results for ocean testing are included. 相似文献