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91.
Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion. 相似文献
92.
This paper addresses a neglected topic in the knowledge management literature: how the size of a network of actors affects the nature of intra-network social relations and knowledge processes. It makes a theoretical contribution to developing understanding in this area drawing on a range of literatures including practice-based perspectives on knowledge, the literature on the embeddedness of social relations, and relevant knowledge management literature. The central focus of this paper is on the relationship between network size, network density, and how these variables affect intra-network knowledge processes. It suggests that as network size increases network density is likely to decrease (as it becomes problematic for the actors in such networks to retain strong ties with a significant proportion of the network's members), which it will be suggested has significant ramifications for intra-network knowledge processes. This paper concludes by reflecting on the implications of the ideas developed for network-based forms of organizing, and innovation processes. 相似文献
93.
Surapon?TangvarasittichaiEmail author Patcharin?Pingmuanglaew Orathai?Tangvarasittichai 《Indian journal of clinical biochemistry : IJCB》2016,31(4):446-451
Hypertension is the most common cardiovascular risk factor. Lipoprotein(a) [Lp(a)], inflammation, oxidative stress and chronic kidney disease (CKD) exacerbate the response to tissue injury and acts as markers of the vascular disease, especially in glomerulosclerosis. We compared the clinical characteristics of 138 non-diabetes hypertensive women (ndHT) patients with 417 non-diabetes normotensive subjects and tested the association of hypertension with Lp(a), inflammation, CKD and oxidative stress by using multiple logistic regression. BP, BMI, waist circumference, creatinine, Lp(a), inflammation and malondialdehyde levels were significantly higher and CKD state in the ndHT patients (p < 0.05). Multiple logistic regression showed hypertension associated with increased Lp(a), inflammation, ORs and 95 % CIs were 2.52 (1.33, 4.80), 2.75 (1.44, 5.27) after adjusting for their covariates. Elevated serum Lp(a) and inflammation levels concomitants with increased oxidative stress and CKD were the major risk factors associated with hypertension and implications for the increased risk of HT and vascular disease. 相似文献
94.
Serap ?uhadar Mehmet K?seo?lu Yasemin ?inpolat Güler Bu?dayc? Murat Usta Tuna Semerci 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2016,26(1):53-60
Introduction
Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.Materials and methods
Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.Results
Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.Conclusion
Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests 相似文献95.
96.
Evrikleia?Tsagala Maria?KordakiEmail author 《Education and Information Technologies》2007,12(4):281-295
This paper aims to determine the factors affecting the decisions of both male and female secondary school pupils whether or
not to pursue undergraduate studies in Computing. It is based on research conducted in Greece, on a sample of 248 pupils,
135 of whom were female. All were aged 17 and about to decide on their future undergraduate studies. Questionnaires were used,
addressing issues in the following four main categories: a) the reasons pupils chose/rejected Computing, b) how family and
friends, the media and the school environment contribute to their decision, c) how pupils perceived their future after studying
Computing and d) how pupils perceived the profile of a computer professional in terms of gender.
相似文献
Maria KordakiEmail: |
97.
A sample of 63 gifted elementary-school students was administered the Bender Visual-Motor Gestalt Test and the Developmental Test of Visual-Motor Integration for comparative purposes and to test Koppitz hypothesis that gifted students have advanced visual-motor development. Group results revealed no significant differences between the two tests, that they did correlate significantly, and that younger students in particular had advanced visual-motor development when tested using these two tools. 相似文献
98.
Howard M. Knoff 《Psychology in the schools》1985,22(4):410-418
Four hundred regular and special educators from New York (a categorical labeling state) and Massachusetts (a noncategorical labeling state) were surveyed on their mainstreaming attitudes and perceptions of handicapped exceptional children. Among the topics investigated were educators' attitudes toward the effects on these children of different educational placements, their reactions to integrating these children into regular classrooms, their knowledge of their special education responsibilities, and their inclusions in their building-level special education processes. Results, implications, and future research directions are discussed, so that services to handicapped exceptional children can be improved and implemented. 相似文献
99.
100.
IPv4, the workhorse protocol of the currently popular TCP/ IP protocol suite, is fast becoming obsolete. The exponential growth
of the Internet is the main reason that has required the creation of the next generation of Internet Protocol-IPv6. IPv6 is
much more flexible and promises to take care of the address space and security issues in the foreseeable future.
Part 1 of the paper lays the foundation of the various issues involved in designing the Internet Protocol and motivates the
need for an upgraded version of this protocol. 相似文献