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, A Leo , Substituent Constants For Correlation Analysis in Chemistry and Biology, John Wiley & Sons, New York, 1979. Leo A. Substituent Constants For

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C. Hansch and A. Leo , Substituent Constants for Correlation Analysis in Chemistry and Biology, Wiley, New York, 1979. Leo A. Substituent

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Abstract  

Few dedicated attempts at comparing the monitoring performance of lower and higher plants have been carried out so far. As a contribution to such an issue, this paper looks into the relative magnitude of elemental signals from epiphytic lichens (Parmelia spp.) and olive tree (Olea europaea Linn.) bark, determined by INAA. A representative set of 12 elements - As, Ba, Br, Ca, Cl, K, Mg, Mn, Na, Sr, V, Zn - was used for an ab initio comparison between raw data and Rb-normalized data, using distribution-free statistics. Correlation analysis shows an overall improvement in the degree of association between bark and lichen signals when proceeding from raw data to relative enrichment. Apart from Cl, no element is enriched in lichens to a higher extent than in bark. Sign tests are quite conclusive: bark factors are either statistically greater than or equal to lichens'. These findings prompt a word of caution when dealing with biological monitoring data, without accounting for soil, rock or litter inputs into the biomonitors' elemental pools.

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The effectiveness of the neutralization process on heavy metals precipitated in sludge has been evaluated using instrumental neutron activation analysis (INAA) facilities at the South African Nuclear Energy Corporation (Necsa). The elemental concentrations of Th, Fe, Ag, Co, Cr, As, Au and K were reduced after the neutralization process with the exception of Mn and Sn which appeared to be enhanced by the neutralization process. Even though the neutralization process was targeted at the basic ferric arsenate compound, it was found to be effective in reducing other elemental concentrations. The variations in the geochemical compositions of the sulphidic ores during treatment at various stages also showed that physical processing stages do not significantly alter the elemental concentrations in the feed materials, however, the chemically active processing stages do. Also, the enhancement of the elements at the chemical stages depends on total quality control, where the application was not very repeatable the pattern of variation of elements at some stages was found to be irregular irrespective of the ore grade. The elements; Sn, Fe, Th, K, Au, Ag, As, Cr, and Co were enhanced in almost all the chemically active stages. Au was much more enhanced during flotation and bio-oxidation processes. Correlation analysis performed to determine the distribution patterns show that Fe, As, Ag and Co are geochemically associated and might be enriched simultaneously.

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Aim: To evaluate endogenous toxic substrates and liver monooxygenase function in cardiosurgical patients with multiple organ dysfunction syndrome (MODS). Methods: 45 patients with MODS and 34 patients with an uneventful postoperative period were studied. The endogenous substrates were quantified with blood middle molecules (MM). Liver monooxygenase function was evaluated with antipyrine (AP) pharmacokinetics. Results: On the first postoperative day, MODS patients were characterized by high concentration of toxic substrates (MM: +43.8%) and a significant decrease in liver monooxygenase function (AP clearance: −44%), while controls patients had a mild increase in endogenous substrates and a slight depression in monooxygenase function. On the 3rd–4th postoperative day, in the main group, endogenous substrates increased (MM: +53.1%), while in the control group toxic substrates decreased (MM: +6.9%). In both groups, an increase in liver monooxygenase function was noticed. Major differences were observed on the 10th–12th postoperative day. In the main group, toxic substrates remained elevated (MM: +37.5%) and monooxygenase function was depressed (AP clearance: −45.4%), while in the control group endogenous substrates and monooxygenase function were equal to the baseline. The correlation analysis showed a negative relationship between AP pharmacokinetics and endogenous substrates. Conclusion: Slowdown in liver microsomal oxidation is one of the main reasons for the accumulation of endogenous toxic substrates in MODS cardiac patients.

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The aims of this study were to detect physiological changes in blood biochemical parameters throughout gestation, to compare the findings in nonpregnant and pregnant Lipizzaner mares in early-mid and late pregnancy, and to provide reference values for clinical chemistry parameters in this horse breed. A total of 136 venous blood samples were collected from 20 pregnant and 10 nonpregnant (control) asymptomatic Lipizzaner broodmares for biochemical analyses. Twelve parameters (albumin, total protein, urea, triglycerides, glucose, creatinine, alkaline phosphatase, aspartate transaminase, glutamate dehydrogenase, gammaglutamyltransferase, creatine kinase and lactate dehydrogenase) were measured. For the statistical analyses, correlation, analysis of variance and Kruskal–Wallis H-test were used to evaluate the possible associations between parameters. Serum triglyceride levels proved to be significantly different in pregnant mares compared to the control group. Total protein and urea levels significantly decreased, while glucose, triglyceride and glutamate dehydrogenase values increased from approx. the fifth month of gestation until parturition. Four biochemical parameters (albumin, aspartate transaminase, total protein and urea) were lower and three other variables (glucose, alkaline phosphatase and creatinine) were significantly higher in late-term pregnant mares than in mares in early or mid-gestation. It is concluded that reference values not only reflect the species, breed and sex but also the reproductive status of animals.

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The effects of two light intensities on the concentration of several flavonoids were investigated in the cotyledons of common buckwheat seedlings. The study was performed on four days old seedlings of cvs. Hruszowska, Panda, Kora and Red Corolla. One group of seedlings was grown under exposure to 180 ± 20 μmol · m−2 · s−1 photosynthetically active radiation, whereas the other group was exposed to 360 ± 20 μmol · m−2 · s−1. The experiment lasted 5 days. The results revealed that light intensity induces changes in the levels of flavonols and flavones. Increased light intensity contributed to a decrease in the concentrations of all flavone C-glucosides: orientin (luteolin-8-C-glucoside) and iso-orientin (luteolin-6-C-glucoside), and apigenin: vitexin (apigenin-8-C-glucoside) and iso-vitexin (apigenin-6-C-glucoside). Simultaneously, a substantial increase in the content of flavonols, i.e. quercetin O-glycosides, was found. To the best of our knowledge, this is the first evidence to demonstrate the contrary responses of plant flavonols and flavones to light intensity. The content of anthocyanin also increased under exposure to higher light intensity. Our results indicate that quercetin O-glycosides can play a similar role to anthocyanins in the cotyledons of common buckwheat seedlings. Results of correlation analysis indicate that the increase in flavonol and anthocyanin concentrations in response to higher light intensity is maintained through reduced accumulation of flavones and proanthocyanidins.

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Abstract  

Crystallisation is generally regarded as a nucleation — growth mechanism of a solid phase and often studied using thermo chemical methods. The present work postulates an analogy to melting processes, looking at melting as nucleation — growth of a liquid phase. The melting process of acetylsalicylic acid single crystals was investigated by DSC measurements under isothermal conditions. The fraction of material molten after a certain time period, α(t), was calculated by integrating the DSC curves. The resulting kinetic curves were fitted using the Avrami-Erofeev equation: –ln(1–α)=kt n, where parameter n was analysed. According to established methods, functions I('2')=[t('2')]/[t('2')+t('3')]100% and I('3')=[t('3')]/[t('3')+t('2')]100% were introduced, where t('2') and t('3') is the absolute time of consumption two- and three-dimension nuclei growth, respectively. Applying correlation analysis, relationships between two- or three-dimensional growth and the independent variables describing the single crystals (for strictly definite trajectories into the space of sizes) were found. Particular correlations were:a) Two-dimensional growth is a function of the total surface area of the crystal, S, and of the surface area of the (ac)-face, S ac; b) Three-dimensional growth is a function of S/M (where M is the mass of the single crystal). It is also a function of S ac/M and of S. The obtained experimental data are explained by the ‘layer’ structure of crystals of acetylsalicylic acid.

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Seasonal changes of nitrogen metabolites and Na + /K + ratio were detected in some wild species inhabiting the western desert of Egypt. Seasons, species and their interactions were important factors affecting the total free amino acids and soluble proteins at Dakhla oasis; however, species diversity is more effective variable in regulating such metabolites at Kharga region. Such plants may respond to their environment either by increasing their water binding molecules or by preventing the formation of amino acids into proteins. Some halophytes and xerophytes may adjust osmotically to stress by the contribution of nitrogen metabolites. On the other hand, Zygophyllum coccineum , the succulent plant, may adapt to environmental conditions through the accumulation of free amino acids. The correlation analysis between Na + /K + ratio with free amino acids, soluble proteins and water content in Balanites aegyptiaca, Salsola imbericata, Tamarix aphylla, Trichodesma africanum and Z. coccineum (Kharga) indicated such changes in ionic fraction or accumulating soluble organic compounds that presumably were osmotically active and contribute to osmotic adjustment. Positive correlation was also found between chlorophyll content with ionic and nitrogen metabolites. It is likely to suggest that Acacia nilotica, Suaeda monoica and Z. coccineum at Dakhla may have changed their soluble proteins or ionic ratio as a consequence of chlorophyll response to stress, while S. imbericata and T. aphylla may control cellular protein contents. On the other hand, the interaction of both nitrogen metabolites and ionic fraction may play an important role of osmoregulation in S. imbericata, Citrullus colocynthis and Z. coccineum at Kharga region.

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Abstract

Analytical data of primary oxidized manganese ores were processed by statistical methods. Six hundred and twenty-one samples were measured (Mn, Fe, Si, and P); thus 2,426 assay data were available. The statistical pointer numbers, the distribution of the elements and the results of the correlational analysis showed the heterogeneity of the ore samples where the measured elements correlated weakly. The samples were grouped by the 4 elements to decrease the heterogeneity and the concentration of elements, and these relationships in the groups were examined. Very few and weak relationships were proved in the groups by the results of the correlational and regressional analysis. It is possible that not the heterogeneity of the samples but one or more syngenetic or postgenetic processes caused the absence of relationships. The multivariate statistical processes (principal component analysis, discriminance analysis) allow the determination of the background factors, namely which are the effects that produced the ore. Consequently — with high probability — the ore was formed by two processes. The most likely are hydrothermal and microbial ones (on the basis of geochemical results), but supergene enrichment processes can also be taken into consideration. Both hydrothermal and microbial processes played a significant role in the majority of the samples (81%), which are the ferruginous manganese ores. In the smaller group of samples (19%) the hydrothermal process predominates but the microbial one is also influential, namely for the low iron-bearing manganese ores of excellent quality.

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