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31.
Lengua Liliana J.; Sadowski Christine A.; Friedrich William N.; Fisher Jennifer 《Canadian Metallurgical Quarterly》2001,69(4):683
Expert ratings and confirmatory factor analyses were used to develop an alternative system for scoring the Child Behavior Checklist (CBCL; T. M. Achenbach, 1991) to measure specific dimensions corresponding to current conceptualizations of child symptomatology. Data were from a nonclinic and 2 independent clinic samples. Subscales measuring Anxiety, Attention Problems/Hyperactivity, Conduct Problems, Depression, Oppositional Defiant, Social Problems/Immaturity, and Somatization were created. Logistic regressions were conducted to evaluate the diagnostic efficiency and discrimination of the new and original approaches to scoring the CBCL. Some of the new subscales demonstrated better sensitivity, positive predictive power, and discriminant validity than the original CBCL subscales; however, subscales from both approaches demonstrated low sensitivity. Results support the use of the new subscales for specific research purposes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Huiyong Yin Jiuchuan Wei Liliana Lefticariu Jianbin Guo Daolei Xie Zilin Li Peng Zhao 《Mine Water and the Environment》2016,35(2):243-252
The study of groundwater flow from the coal seam floor is critical to safe mining operations in China. We developed a numerical simulation model to describe flood water pathways during mining, using the field conditions present at the no. 4196 west work face in the Panxi longwall coal mine, Shandong Province, China, Groundwater flow analysis revealed unusual values for the failure depth of the coal seam floor. The high ground stress and underground pressure, excavation length, width of working face, poor mechanical properties of aquitards, and expansion of fractures by groundwater infiltration all contribute to groundwater flow into the mine. The modeling results predict the time and longwall locations associated with the maximum likelihood of flood occurrence. Such results can be used by decision makers to improve mine design and safety. 相似文献
33.
Dr. Umberto Maria Battisti Dr. Chunxia Gao Oscar Nilsson Dr. Fady Akladios Dr. Aleksei Lulla Dr. Agnieszka Bogucka Dr. Amalyn Nain-Perez Dr. Liliana Håversen Dr. Woonghee Kim Prof. Jan Boren Prof. Marko Hyvönen Prof. Mathias Uhlen Prof. Adil Mardinoglu Prof. Morten Grøtli 《Chembiochem : a European journal of chemical biology》2023,24(1):e202200339
Enzymes are effective biological catalysts that accelerate almost all metabolic reactions in living organisms. Synthetic modulators of enzymes are useful tools for the study of enzymatic reactions and can provide starting points for the design of new drugs. Here, we report on the discovery of a class of biologically active compounds that covalently modifies lysine residues in human liver pyruvate kinase (PKL), leading to allosteric activation of the enzyme (EC50=0.29 μM). Surprisingly, the allosteric activation control point resides on the lysine residue K282 present in the catalytic site of PKL. These findings were confirmed by structural data, MS/MS experiments, and molecular modelling studies. Altogether, our study provides a molecular basis for the activation mechanism and establishes a framework for further development of human liver pyruvate kinase covalent activators. 相似文献
34.
The application of metal mordants is usually necessary in dyeing of wool with natural dyes to improve the dye exhaustion and fastness properties. The majority of metal salts generally used as mordants are considered as toxic and it is important to find replacements for them. Plant sources with high content of tannins are good candidates as bio-mordant or colourant to overcome this drawback. In this study, the waste fallen leaves of pomegranate tree were used as a source of natural dye for the eco-friendly dyeing of wool fabric without the use of metal mordants. The dyeing process variables including dye concentration, dyebath pH, and temperature were optimised using response surface methodology to obtain the highest colour strength. The colour strength was increased by increasing the natural dye powder up to 100%owf while the optimum pH and dyebath temperature were 4 and 100°C, respectively. The sample dyed under the optimal condition exhibited good fastness properties against washing and light. This study approved the potential of Punica granatum fallen leaves for the dyeing of wool without any mordant, while high fastness properties were obtained. 相似文献
35.
Cristina Elena Ciomaga Mirela Airimioaei Valentin Nica Luminita M. Hrib Ovidiu F. Caltun Alexandra R. Iordan Carmen Galassi Liliana Mitoseriu Mircea N. Palamaru 《Journal of the European Ceramic Society》2012,32(12):3325-3337
Magnetoelectric composites of xNiFe2O4–(1 ? x)Pb(Zr,Ti)O3 with x = 2, 5, 10, 20, 30% were prepared by citrate–nitrate combustion using PZT-based template powders. In order to ensure a better connectivity of dissimilar phases, we have used chemical methods for preparation in situ composites, followed by adequate sintering procedure. The structural, microstructural and functional properties of di-phase magnetoelectric composites of NiFe2O4–PZT are reported. The XRD analysis is demonstrating the synthesis of pure ferrite phase directly on the ferroelectric templates. An excellent mixing was obtained in the composite powders, as proved by a detailed SEM analysis.The magnetic and dielectric behaviors of the ceramic composites vary with the ratio of the two phases. The dielectric behavior is greatly influenced by the magnetic phase. The magnetoelectric (ME) coefficient was measured as a function of applied DC magnetic field. The maximum ME coefficient (dE/dH) varies from 0.0011 mV/(cm Oe) to 0.5 mV/(cm Oe) with increasing of NF addition. 相似文献
36.
Blanca Estela Enríquez‐Fernández Liliana Álvarez de la Cadena y Yañez María Elena Sosa‐Morales 《International Journal of Food Science & Technology》2011,46(6):1231-1237
Stability of palm olein (PO) and a blend 50% palm olein/50% canola oil (POC) during deep‐fat frying at 180 °C of French fries (FF) or chicken nuggets (CN) was studied through the determination of physical and chemical parameters in the fresh and used oils. Degradation at the end of the study resulted in total polar compounds of 12–13.5% for PO and 11.5–14.5% for POC and viscosity of 65–123.3 cP for PO and 63–72.8 cP for POC. Lower peroxide values (5.33–6.32) were obtained for the blend (PO had 5.21–8.55). Food type affected colour parameters and p‐anisidine value of the oils. For CN, the lowest fat content and higher hardness were obtained when they were fried in PO. CN caused a faster deterioration in the oils, in comparison with FF, especially in POC. Gas chromatography allowed to observe differences in fatty acids composition for both used oils. 相似文献
37.
Positron emission tomography (PET) is an imaging procedure used mainly in the diagnosis and treatment of diseases. PET is also used in the preclinical research studies of small animals. However, researchers may have difficulty interpreting the particularly low-resolution images obtained via this procedure. This paper presents a new method of increasing the resolution of PET images through the use of super-resolution techniques. Aside from being resistant to the noise and other degradations that plague PET images, our proposed algorithm is also capable of preserving important structures (e.g. lesions). To this end, the proposed objective function includes a term based on the modified total variation model which allows the user to preserve texture and to deal with noise without incurring the artefacts that typically arise when the total variation norm is used. The present study shows the effectiveness of the method in recovering structures and details and indicates that, in most cases, it outperforms other state-of-the-art methods. 相似文献
38.
Hristo M. Najdenski Liliana G. Gigova Ivan I. Iliev Plamen S. Pilarski Jaromir Lukavský Iva V. Tsvetkova Mariana S. Ninova Vesselin K. Kussovski 《International Journal of Food Science & Technology》2013,48(7):1533-1540
In vitro activity of nine cyanobacterial and ten microalgal newly isolated or culture collection strains against eight significant food‐borne pathogens has been evaluated and compared. Water extracts and culture liquids of Gloeocapsa sp. and Synechocystis sp. demonstrated the widest spectrum of activity with minimal inhibitory concentration (MIC) ranging from 1.56 to 12.5 mg mL?1. Culture liquid of Anabaena sp. had the highest activity (MIC = 0.39 mg mL?1) but only to Gram‐positive bacteria. Ethanol extracts and fatty acids from all cyanobacteria and microalgae were active against Streptococcus pyogenes and/or Staphylococcus aureus. The fatty acids of Synechocystis sp. inhibited the growth of Bacillus cereus, Escherichia coli and Candida albicans (MIC values of 2.5–1.25 mg mL?1, respectively). Exopolysaccharides (EPS) of Gloeocapsa sp. were the sample that exhibited activity against all test pathogens with lowest MIC values (0.125–1 mg mL?1). High activity with a narrower range of susceptible targets demonstrated the exopolysaccharides of Synechocystis sp. and Rhodella reticulata. Antimicrobial activity was proven for phycobiliproteins isolated from Synechocystis sp., Arthrospira fusiformis, Porphyridium aerugineum and Porphyridium cruentum, respectively. In conclusion Gloeocapsa sp. and Synechocystis sp. and especially their exopolysaccharides showed the most promising potential against the examined food pathogens. 相似文献
39.
40.
Liliana N. Ceci Amalia A. Carelli 《Journal of the American Oil Chemists' Society》2010,87(10):1189-1197
The relation between oxidative stability and composition in 58 virgin olive oils from different cultivars and Argentinian
regions was studied over four harvest years. The oxidative stability of the oils was assessed using the OSI index (110 °C,
20 L/h air flow). A multiple linear regression model is proposed using OSI values as the dependent variable (multiple R = 0.933, p = 1 × 10−15), with positive contributions of the independent variables: fatty acid composition [oleic acid/(linoleic acid + linolenic
acid), 55.3%, p = 1 × 10−15], total polyphenols (24.1%, p = 1.8 × 10−9), carotenes (4.8%, p = 6.1 × 10−5), β-tocopherol (1.9%, 6.0 × 10−3) and other compounds (13.9%). Highly significant correlation was observed between oxidative stability indexes estimated by
the compositional model and those experimentally determined by Rancimat method (b = 0.981, R = 0.924). Chlorophylls and Δ-5-avenasterol contributions to the model were non-significant when variables related with fatty
acids and polyphenols were included. The results suggest that the fatty acid composition and the polyphenol content are the
main factors that affect the oxidative stability of olive oils. The proposed model allows the estimation of the oxidative
stability in olive oils independently of the cultivar. The model was obtained also taking into account samples that lie out
of the international legal limits in some compositional values due to natural variations. 相似文献