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81.
82.
Julia Hodges Susan Bridges Charles Sparrow Govinda Weerakkody Bo Tang Chen Jun 《Applied Artificial Intelligence》2013,27(4):385-396
Scientists at the Mississippi State University Diagnostic Instrumentation and Analysis Laboratory and the Idaho National Engineering and Environmental Laboratory (INEEL) have developed an expert system for a noninvasive characterization of containerized radiological waste. The characterization of the containers is necessary for determining their proper disposition. Three prototypes were developed, with each using a different method of handling uncertainty - a fuzzy system, a Bayesian network system, and a neural network system. The performance of each expert system was assessed to determine how well it modeled the decisions made by the INEEL domain expert. The prototype systems were also analyzed to measure the agreement in their decisions, the domain expert's decisions, and the decisions made by two additional experts. The neural network prototype was further analyzed to determine how consistent it was in its assessments. This paper describes the analysis of the performance of the three expert system prototypes. 相似文献
83.
It is widely accepted that corporate reputation plays an important role in determining the impact of crises on firms. Crises may erode corporate reputation. However, reputation may also attenuate the negative effects of crises. This study investigates how corporate reputation moderates the relationship between crisis occurrence and customer loyalty which is expected to decrease given a crisis. Drawing on opposing theories, namely dissonance theory and expectancy‐violation, we conduct a scenario experiment set in the airline industry. Results demonstrate that the moderating effect is weaker in the case of a favourable corporate reputation. This may indicate that a pre‐existing favourable reputation does not shield the firm from the negative effects of the crisis, but may rather present a liability because customers have higher expectations with regard to well‐reputed firms. Contrary to that, ill‐reputed firms have less to lose in the case of a crisis and suffer comparatively smaller decreases in customer loyalty. Marketing management might take into account the role of crisis and reputation management for customer bonding strategies while crisis management should recognize the importance of reputation effects in crises given their impact on customer loyalty and firm profitability. 相似文献
84.
Julia Dittrich Susen Becker Max Hecht Uta Ceglarek 《Proteomics. Clinical applications》2015,9(1-2):5-16
The simultaneous quantification of protein concentrations via proteotypic peptides in human blood by liquid chromatography coupled to quadrupole MS/MS is an important field of bioanalytical research with a high potential for routine diagnostic applications. This review summarizes currently available sample preparation procedures and trends for absolute protein quantification in blood using LC-MS/MS. It discusses approaches of transferring established qualitative protocols to a quantitative analysis regarding their reliability and reproducibility. Techniques used to enhance method sensitivity such as the depletion of high-abundant proteins or the immunoaffinity enrichment of proteins and peptides are described. Furthermore, workflows for (i) protein denaturation, (ii) disulfide bridge reduction and (iii) thiol alkylation as well as (iv) enzymatic digestion for absolute protein quantification are presented. The main focus is on the tryptic digestion as a bottleneck of protein quantification via proteotypic peptides. Conclusively, requirements for a high-throughput application are discussed. 相似文献
85.
Bjoern Titz Karsta Luettich Patrice Leroy Stephanie Boue Gregory Vuillaume Terhi Vihervaara Kim Ekroos Florian Martin Manuel C. Peitsch Julia Hoeng 《International journal of molecular sciences》2016,17(9)
Smoking is a major risk factor for several diseases including chronic obstructive pulmonary disease (COPD). To better understand the systemic effects of cigarette smoke exposure and mild to moderate COPD—and to support future biomarker development—we profiled the serum lipidomes of healthy smokers, smokers with mild to moderate COPD (GOLD stages 1 and 2), former smokers, and never-smokers (n = 40 per group) (ClinicalTrials.gov registration: ). Serum lipidome profiling was conducted with untargeted and targeted mass spectrometry-based lipidomics. Guided by weighted lipid co-expression network analysis, we identified three main trends comparing smokers, especially those with COPD, with non-smokers: a general increase in glycero(phospho)lipids, including triglycerols; changes in fatty acid desaturation (decrease in ω-3 polyunsaturated fatty acids, and an increase in monounsaturated fatty acids); and an imbalance in eicosanoids (increase in 11,12- and 14,15-DHETs (dihydroxyeicosatrienoic acids), and a decrease in 9- and 13-HODEs (hydroxyoctadecadienoic acids)). The lipidome profiles supported classification of study subjects as smokers or non-smokers, but were not sufficient to distinguish between smokers with and without COPD. Overall, our study yielded further insights into the complex interplay between smoke exposure, lung disease, and systemic alterations in serum lipid profiles. NCT01780298相似文献
86.
Jeffrey Perl Sahir Kalim Ron Wald Marc B. Goldstein Andrew T. Yan Nazanin Noori Mercedeh Kiaii Julia Wenger Christopher Chan Ravi I. Thadhani S. Ananth Karumanchi Anders H. Berg 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(4):510-521
Introduction Among conventional hemodialysis (CHD) patients, carbamylated serum albumin (C‐Alb) correlates with urea and amino acid deficiencies and is associated with mortality. We postulated that reduction of C‐Alb by intensive HD may correlate with improvements in protein metabolism and cardiac function. Methods One‐year observational study of in‐center nocturnal extended hemodialysis (EHD) patients and CHD control subjects. Thirty‐three patients receiving 4‐hour CHD who converted to 8‐hour EHD were enrolled, along with 20 controls on CHD. Serum C‐Alb, biochemistries, and cardiac MRI parameters were measured before and after 12 months of EHD. Findings EHD was associated with reduction of C‐Alb (average EHD change ?3.20 mmol/mol [95% CI ?4.23, ?2.17] compared to +0.21 [95% CI ?1.11, 1.54] change in CHD controls, P < 0.001). EHD was also associated with increases in average essential amino acids (in standardized units) compared to CHD (+0.38 [0.08, 0.68 95%CI]) vs. ?0.12 [?0.50, 0.27, 95% CI], P = 0.047). Subjects who reduced C‐Alb more than 25% were found to have reduced left ventricular mass, increased urea reduction ratio, and increased serum albumin compared to nonresponders, and % change in C‐Alb significantly correlated with % change in left ventricular mass. Discussion EHD was associated with reduction of C‐Alb as compared to CHD, and reduction of C‐Alb by EHD correlates with reduction of urea. Additional studies are needed to test whether reduction of C‐Alb by EHD also correlates with improved clinical outcomes. 相似文献
87.
de Melo Henrique João Miller Isidro Julia Saez Cristina Dos Santos Elisama V. Rodrigo Manuel A. 《Journal of Applied Electrochemistry》2022,52(9):1317-1326
Journal of Applied Electrochemistry - This paper evaluates the remediation of soil spiked with lindane using a combined treatment consisting of electrokinetic soil flushing (EKSF) with air... 相似文献
88.
Santiago P. Aubourg Julia Vinagre Alicia Rodríguez Vanesa Losada M. Anglica Larraín Vilma Quitral Julio Gmez Liliana Maier Emma Wittig 《European Journal of Lipid Science and Technology》2005,107(6):411-417
Coho salmon (Oncorhynchus kisutch) is a fatty fish species whose farming production has greatly increased in recent years. Lipid damage produced during Coho salmon chilled storage was studied for up to 24 d. Lipid hydrolysis (free fatty acids, FFA) and oxidation (conjugated dienes; peroxide value, PV; thiobarbituric acid index, TBA‐i; fluorescent compounds formation, FR; browning development) were determined and compared to lipid composition (polyene index, PI; astaxanthin, AX) changes and sensory assessment (rancid odour development) results. Most lipid damage indices developed slowly during storage; thus, values obtained for FFA, PV, TBA‐i and FR were in all cases under 1.5 g/100 g, 4.0 meq oxygen/kg lipid, 0.40 mg malondialdehyde/kg muscle and 0.40, respectively. Odour assessment showed a significant (p <0.05) rancidity development at day 10, when compared to starting fish material; then, non‐acceptable values were obtained at days 19 and 24. The PI analysis showed not many differences during the storage time, with the lowest mean value at day 19. AX analysis indicated a relatively high content in the white muscle, which was maintained till the end of the experiment. A low oxidation development is concluded for Coho salmon lipids when compared to other fatty fish species under the same chilling conditions. AX was found to contribute to the oxidation stability of Coho salmon lipids, due to its free radical scavenger properties. 相似文献
89.
Pitt William R.; Goodfellow Julia M. 《Protein engineering, design & selection : PEDS》1991,4(5):531-537
Previous analysis of the distribution of experimental solventmolecule positions around amino acid side chains showed thatdistinct clustering occurred close to polar or charged atomsin proteins. We have used those data to predict likely solventpositions around proteins not used in our initial analysis.We envisage that this algorithm, AQUARIUS, will be useful forfinding solvent positions in electron density maps generatedby protein crystallography and as useful starting positionsfor solvent molecules in computer simulation studies of macromolecules. 相似文献
90.
Ana Isabel Rodríguez-Bernaldo De Quirós Julia López-Hernández María José González-Castro Carlos De la Cruz-García Jesús Simal-Lozano 《European Food Research and Technology》2000,210(3):226-230
The effects of four culinary treatments (steaming and boiling in a covered pot, a pressure cooker or a microwave oven) on
the volatile component profile of green beans were evaluated. Volatile compounds in raw and cooked beans were analysed by
means of dynamic headspace sampling onto an adsorbent, followed by microwave desorption into a gas chromatograph equipped
with a mass spectrometric detector. Twenty-seven compounds were identified, including alcohols, aldehydes, ketones, esters,
terpenes, sulphur compounds and alkenes. All of the thermal treatments caused important changes in the volatile compound profile
in particular an increase in carbonyl compounds and a decrease in alcohol compounds, most notably in the case of the covered
pot. It is concluded that the change in aroma during the cooking of green beans depends on compounds from lipid oxidation
as well as compounds from other types of reactions, for instance the Strecker degradation.
Received: 8 March 1999 / Revised version: 23 April 1999 相似文献