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61.
Rushton J. Philippe; Jackson Douglas N.; Paunonen Sampo V. 《Canadian Metallurgical Quarterly》1981,88(6):582
Suggests that substantial consistency can be observed in personality, as reflected in both behavior and judges' ratings, when the principle of aggregration is applied to traditional nomothetic assessment procedures and the results are interpreted in terms of classical reliability theory. It is demonstrated that conclusions by D. T. Kenrick and D. O. Stringfield (see record 1980-07621-001) about the improvement in predictive power stemming from an idiographic analysis do not follow from their data, as they confound trait consistency and trait extremity and fail to take account of restriction and inflation of range effects. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
63.
Nurul Aqilah Mohd Zaini Azizah OsmanAzizah Abdul Hamid Afshin EbrahimpourNazamid Saari 《Food chemistry》2013
Membrane-bound polyphenoloxidase (mPPO) an oxidative enzyme which is responsible for the undesirable browning reaction in Snake fruit (Salacca zalacca (Gaertn.) Voss) was investigated. The enzyme was extracted using a non-ionic detergent (Triton X-114), followed by temperature-induced phase partitioning technique which resulted in two separate layers (detergent-poor phase at the upper layer and detergent-rich phase at the lower layer). The upper detergent-poor phase extract was subsequently fractionated by 40–80% ammonium sulfate and chromatographed on HiTrap Phenyl Sepharose and Superdex 200 HR 10/30. The mPPO was purified to 14.1 folds with a recovery of 12.35%. A single prominent protein band appeared on native-PAGE and SDS–PAGE implying that the mPPO is a monomeric protein with estimated molecular weight of 38 kDa. Characterization study showed that mPPO from Snake fruit was optimally active at pH 6.5, temperature 30 °C and active towards diphenols as substrates. The Km and Vmax values were calculated to be 5.46 mM and 0.98 U/ml/min, respectively, when catechol was used as substrate. Among the chemical inhibitors tested, l-cysteine showed the best inhibitory effect, with an IC50 of 1.3 ± 0.002 mM followed by ascorbic acid (1.5 ± 0.06 mM), glutathione (1.5 ± 0.07 mM), EDTA (100 ± 0.02 mM) and citric acid (186 ± 0.16 mM). 相似文献
64.
65.
Novel source of semicarbazide: levels of semicarbazide in cooked crayfish samples determined by LC/MS/MS. 总被引:1,自引:0,他引:1
Nitrofuran antibiotics were previously used in animal healthcare but are now prohibited. Semicarbazide is a breakdown product of 5-nitrofurazone and protein-bound semicarbazide is used as a marker residue for the illegal use of 5-nitrofurazone. However, the presence of the prohibited semicarbazide has been reported in some food items of animal origin. A novel observation is reported that semicarbazide can be detected in Finnish crayfish samples, i.e. crustacea, never medicated with nitrofurazone. The origin of the semicarbazide is presently unknown. Positive identification was undertaken by liquid chromatography coupled with tandem mass spectrometry detection. The level of semicarbazide was determined as the protein-bound form as well as the total amount of semicarbazide in the sample. The average levels of total semicarbazide and the protein-bound form were 4.2 and 0.5 ng g(-1) fresh crayfish meat, respectively. All the tested samples (n = 18) contained traces of semicarbazide, the highest amount being 12 ng g(-1) fresh crayfish meat. 相似文献
66.
New raw materials for transportation fuels need to be introduced, in order to fight against climate change and also to cope with increasing risks of availability and price of oil. Peat has been recognised suitable raw material option for diesel produced by gasification and Fischer–Tropsch (FT) synthesis. The energy content of Finnish peat reserves is remarkable. In this study, the greenhouse impact of peat-based FT diesel production and utilisation in Finland was assessed from the life-cycle point of view. In 100 year's time horizon the greenhouse impact of peat-based FT diesel is likely larger than the impact of fossil diesel. The impact can somewhat be lowered by producing peat from the agricultural peatland (strong greenhouse gas emissions from the decaying peatlayer are avoided) with new peat production technique, and utilising the produced biomass from the after-treatment area for diesel also. If diesel production is integrated with pulp and paper mill to achieve energy efficiency benefits and if the electricity demand can be covered by zero emission electricity, the greenhouse impact of peat-based FT diesel reduces to the level of fossil diesel when agricultural peatland is used, and is somewhat higher when forestry-drained peatland is used as raw material source. 相似文献
67.
Nazamid Bin Saari Shuji Fujita Kazuyuki Haraguchi Tetsuzo Tono 《Journal of the science of food and agriculture》1994,65(2):153-156
Basic ascorbate oxidase of the multiple enzyme forms existing in young fruit of satsuma mandarin (Citrus unshiu Marc) has been separated and subsequently purified to electrophoretic homogeneity through (NH4)2SO4 fractionation and chromatographies on DEAE-Toyopearl 650M, CM-Sephadex C-50 and Sephadex G-100. The native molecular weight was estimated to be 141 kDa by gel filtration and composed of two non-identical subunits with an apparent mass of 74 kDa and 62 kDa. The optimum pH was found to be 5.5 with reasonable stability between pH 5 and 8. The enzyme had an optimum temperature at 45°C and was stable up to 50°C upon heat treatment for 5 min. The presence of sodium diethyldithiocarbamate, metabisulphite and potassium cyanide completely inhibited the enzyme activity. Fluoride also inhibited the activity substantially at higher concentrations. Other tnonovalent and divalent metal ions did not have inhibitory effects. 相似文献
68.
Crude extracts of root, leaf and fruit of Morinda citrifolia were fractionated on a Sephadex LH-20 column with ethanol as eluate. Based on UV absorption intensity of phenolic compound (725 mm) the Sephadex LH-20 column was able to separate fruit, leaf and root extracts into six, five and five fractions, respectively. The results showed that all the fractions tested exhibited considerably high antioxidative activity in the ferric thiocyanate assay and thiobarbituric acid test and the activities of some of the fractions were as good as those of either tocopherol or BHT. The fractions from different parts of the plants were found to contain different amounts of total phenolic compounds, which, interestingly, do not correspond to the antioxidative activity measured. This is probably due to the presence of different phenolics in the samples, with different antioxidative activities which involves various mechanisms inhibiting the oxidation process. The study suggested that root, leaf and fruit of M. citrifolia might contribute significantly to exogenous antioxidant which is crucial in combating oxidative stress. 相似文献
69.
Teacher personality traits and student instructional ratings in six types of university courses. 总被引:3,自引:0,他引:3
Murray Harry G.; Rushton J. Philippe; Paunonen Sampo V. 《Canadian Metallurgical Quarterly》1990,82(2):250
Colleague ratings of 29 personality traits were studied in relation to student ratings of teaching effectiveness in a sample of 46 psychology teachers. Instructors were evaluated in six different types of university courses, ranging from freshman lecture classes to graduate research seminars. Major findings were as follows: (1) Rated teaching effectiveness varied substantially across different types of courses for a given instructor; (2) teaching effectiveness in each type of course could be predicted with considerable accuracy from colleague ratings of personality; and (3) the specific personality traits contributing to effective teaching differed markedly for different course types. It was concluded that psychology instructors tend to be differentially suited to different types of courses and furthermore that the compatibility of instructors to courses is determined in part by personality characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
I Normah B Jamilah N Saari Yaakob B Che Man 《Journal of the science of food and agriculture》2004,84(11):1290-1298
The chemical and taste characteristics of threadfin bream (Nemipterus japonicus) hydrolysate produced by Alcalase hydrolysis of the fish muscle (pH 8.5, 60 °C, 120 min, enzyme/substrate ratio 20 g kg?1) were studied. Umami, bitter and fishy were the dominant tastes. The bitter amino acids methionine, valine, isoleucine, phenylalanine, leucine and tyrosine comprised 317 mg g?1 of the total amino acids present. The umaminess could be due to the presence of high contents of glutamic acid and inosine 5′‐monophosphate. SDS‐PAGE analysis showed that the peptides in the hydrolysate had molecular weights ranging between 7.2 and 64 kDa. Copyright © 2004 Society of Chemical Industry 相似文献