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1

Data Stream Classification Using Classifier Ensemble

100%

Woźniak M., Kasprzak A.

Schedae Informaticae

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2014

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vol. 23

PL

For the contemporary business, the crucial factor is making smart decisions on the basis of the knowledge hidden in stored data. Unfortunately,m traditional simple methods of data analysis are not sufficient for efficient management of modern enterprizes, because they are not appropriate for the huge and growing amount of the data stored by them. Additionally data usually comes continuously in the form of so-called data stream. The great disadvantage of traditional classification methods is that they assume that statistical properties of the discovered concept are being unchanged, while in real situation, we could observe so-called concept drift, which could be caused by changes in the probabilities of classes or/and conditional probability distributions of classes. The potential for considering new training data is an important feature of machine learning methods used in security applications (spam filtering or intrusion detection) or decision support systems for marketing departments, which need to follow the changing client behavior. Unfortunately, the occurrence of concept drift dramatically decreases classification accuracy. This work presents the comprehensive study on the ensemble classifier approach applied to the problem of drifted data streams. Especially it reports the research on modifications of previously developed Weighted Aging Classifier Ensemble (WAE) algorithm, which is able to construct a valuable classifier ensemble for classification of incremental drifted stream data. We generalize WAE method and propose the general framework for this approach. Such framework can prune an classifier ensemble before or after assigning weights to individual classifiers. Additionally, we propose new classifier pruning criteria, weight calculation methods, and aging operators. We also propose rejuvenating operator, which is able to soften the aging effect, which could be useful, especially in the case if quite ”old” classifiers are high quality models, i.e., their presence increases ensemble accuracy, what could be found, e.g., in the case of recurring concept drift. The chosen characteristics of the proposed frameworks were evaluated on the basis of the wide range of computer experiments carried out on the two benchmark data streams. Obtained results confirmed the usability of proposed method to the data stream classification with the presence of incremental concept drift.

2

Aromatic indolinic aminoxyls as antioxidants in cardiac sarcoplasmic reticulum lipid and protein oxidation.

81%

Kulawiak-Gałąska D., Woźniak M., Greci L.

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2002

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vol. 49

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issue 1

43-49

EN

The results presented demonstrate the influence of aromatic indolinic aminoxyls: 1,2-dihydro-2-ethyl-2-phenyl-3H-indole-3-phenylimino-1-oxyl (IA-C2) and 1,2-dihydro-2-octadecyl-2-phenyl-3H-indole-3-phenylimino-1-oxyl (IA-C18) on oxidation of lipids and proteins of cardiac sarcoplasmic reticulum membranes. We have used doxorubicin and t-butyl hydroperoxide as agents inducing oxidative stress in isolated rat cardiac sarcoplasmic reticulum membrane system. Carbonyl groups were measured as the end product of membrane protein oxidation, and thiobarbituric acid reactive substances were assessed as a marker of lipid peroxidation. Inhibition of peroxidation of certain membrane components depends on the length of acyl chain. Aminoxyl IA-C2 inhibits the lipid peroxidation process while IA-C18 is an efficient protector against protein oxidation.

3

Diversity of the effect of phosphatidylcholine and sphingomyelin on adenylate deaminase from pig brain

81%

Woźniak M., Purzycka-Preis J., Kossowska E., Żydowo M. M.

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issue 3

285-290

4

Automatic diagnosis of primary headaches by machine learning methods

81%

Krawczyk B., Simić D., Simić S., Woźniak M.

Open Medicine

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2013

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vol. 8

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issue 2

157-165

EN

Primary headaches are common disease of the modern society and it has high negative impact on the productivity and the life quality of the affected person. Unfortunately, the precise diagnosis of the headache type is hard and usually imprecise, thus methods of headache diagnosis are still the focus of intense research. The paper introduces the problem of the primary headache diagnosis and presents its current taxonomy. The considered problem is simplified into the three class classification task which is solved using advanced machine learning techniques. Experiments, carried out on the large dataset collected by authors, confirmed that computer decision support systems can achieve high recognition accuracy and therefore be a useful tool in an everyday physician practice. This is the starting point for the future research on automation of the primary headache diagnosis.

5

Kinetic properties of AMP deaminase in acute experimental pancreatitis

71%

Kossowska E., Purzycka-Preis J., Woźniak M., Żydowo M., Śledziński Z.

Acta Biochimica Polonica

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1994

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vol. 41

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issue 2

158-160

6

Purification and regulatory properties of pig kidney AMP deaminase

71%

Prus E., Purzycka-Preis J., Woźniak M., Żydowo M.

Acta Biochimica Polonica

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1980

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vol. 27

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issue 3-4

241-248

7

Inhibitory effect of 2-hydroxyestradiol on lipid peroxidation in placental microsomes

70%

Jankowski K., Kulawiak D., Woźniak M.

Acta Biochimica Polonica

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1994

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vol. 41

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issue 2

151-152

8

Dual effect of 2-methoxyestradiol on cell cycle events in human osteosarcoma 143B cells.

62%

Gołębiewska J., Rozwadowski P., Spodnik J. H., Knap N., Wakabayashi T., Woźniak M.

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2002

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vol. 49

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issue 1

59-65

EN

We have demonstrated for the first time that the steroid metabolite, 2-methoxyestradiol (2-ME) is a powerful growth inhibitor of human osteosarcoma 143 B cell line by pleiotropic mechanisms involving cell cycle arrest at two different points and apoptosis. The ability of 2-ME to inhibit cell cycle at the respective points has been found concentration dependent. 1 μM 2-ME inhibited cell cycle at G1 phase while 10 μM 2-ME caused G2/M cell cycle arrest. As a natural estrogen metabolite 2-ME is expected to perturb the stability of microtubules (MT) in vivo analogously to Taxol - the MT binding anticancer agent. Contrary to 2-ME, Taxol induced accumulation of osteosarcoma cells in G2/M phase of cell cycle only. The presented data strongly suggest two different mechanisms of cytotoxic action of 2-ME at the level of a single cell.

9

A possible involvement of plasma membrane NAD(P)H oxidase in the switch mechanism of the cell death mode from apoptosis to necrosis in menadione-induced cell injury.

62%

Niemczyk E., Majczak A., Hallmann A., Kędzior J., Woźniak M., Wakabayashi T.

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vol. 51

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issue 4

1015-1022

EN

The effects of inhibitors of plasma membrane NADPH oxidase on menadione-induced cell injury processes were studied using human osteosarcoma 143B cells. The intracellular level of superoxide in the cells treated with menadione for 6 h reached a maximum followed by an abrupt decrease. The population of apoptotic cells detected by Annexin V and propidium iodide double staining also reached its maximum at 6 h of menadione-treatment while that of necrotic cells increased continuously reaching 90% of the total population at 9 h of the treatment. Pretreatment of the cells with inhibitors of NADPH oxidase, including diphenyliodonium chloride, apocynin, N-vanillylnonanamide and staurosporine was effective in lowering the menadione-induced elevations of superoxide, and also in the suppression of the switch of the cell death mode from apoptosis to necrosis in menadione-treated cells except for the case of staurosporine. These results strongly suggest that superoxide generated by NADPH oxidase, besides that generated by the mitochondria, may contribute to the remarkable increase in the intracellular level of superoxide in the cells treated with menadione for 6 h resulting in the switch from apoptosis to necrosis, although a direct evidence of the presence of active and inactive forms of NADPH oxidase in control and menadione-treated 143B cells is lacking at present.

10

Effect of pentoxifylline on proteinuria, markers of tubular injury and oxidative stress in non-diabetic patients with chronic kidney disease - placebo controlled, randomized, cross-over study

52%

Renke M., Tylicki L., Rutkowski P., Knap N., Ziętkiewicz M., Neuwelt A., Aleksandrowicz E., Łysiak-Szydłowska W., Woźniak M., Rutkowski B.

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2010

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vol. 57

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issue 1

119-123

EN

Background: Inhibition of the renin-angiotensin-aldosterone system (RAAS) with angiotensin converting enzyme inhibitors (ACEI) and/or angiotensin II subtype 1 receptor antagonists (ARB) is a common strategy used in the management of patients with chronic kidney disease (CKD). However, there is no universal therapy that can stop progression of CKD. Pentoxifylline (PTE) is a non-specific phosphodiesterase inhibitor with anti-inflammatory properties. It has been reported to have promising effects in CKD treatment. Methods: In a placebo-controlled, randomized, cross-over study we evaluated the influence of PTE (1200 mg/day) added to RAAS blockade on proteinuria, surrogate markers of tubular injury and oxidative stress-dependent products in 22 non-diabetic patients with proteinuria (0.4-4.3 g per 24h) with normal or declined kidney function [eGFR 37-178 mL/min]. In an eight-week run-in period, therapy using ACEI and/or ARB was adjusted to achieve a blood pressure below 130/80 mm Hg. Next, patients were randomly assigned to one of two treatment sequences: PTE/washout/placebo or placebo/washout/PTE. Clinical evaluation and laboratory tests were performed at the randomization point and after each period of the study. Results: The PTE therapy reduced proteinuria (by 26%) as compared to placebo. There were no differences in α1-microglobulin, urine excretion of N-acetyl-β-d-glucosaminidase (NAG), hsCRP, the urinary excretion of 15-F2t-isoprostane, blood pressure (BP), eGFR and serum creatinine between the PTE and placebo groups. Conclusion: Pentoxifylline may decrease proteinuria in non-diabetic patients with CKD.

11

Partial characterization of human choriocarcinoma cell line JAR cells in regard to oxidative stress.

52%

Hallmann A., Klimek J., Masaoka M., Kamiński M., Kędzior J., Majczak A., Niemczyk E., Woźniak M., Trzonkowski P., Wakabayashi T.

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vol. 51

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issue 4

1023-1038

EN

Characterization of free radical-induced cell injury processes of placenta cells is of vital importance for clinical medicine for the maintenance of intrauterine fetal life. The present study has analyzed cell injury processes in cells of the choriocarcinoma cell line JAR treated with menadione, an anticancer drug, and Hg2O2 in comparison to osteosarcoma 143B cells using electron microscopic and flow cytometric techniques. Flow cytometry on JAR cells exposed to 100 μM menadione and double-stained with Annexin V and propidium iodide (PI) detected apoptotic cells reaching the maximum after 4 h of incubation with a rapid decrease thereafter. Viable cells became decreased to 46% of the control after 2 h of incubation, reaching 5% after 4 h. Cells stainable with both Annexin V and PI began to increase distinctly after 2 h of incubation, reaching 55% after 4 h. Electron microscopy showed that cells stainable with both dyes specified above had condensed nuclei and swollen cytoplasm, suggesting that they were undergoing a switch of the cell death mode from apoptosis to necrosis. On the other hand, 90% of 143B cells remained intact after 4 h of menadione treatment although the intracellular levels of superoxide were always higher than those of JAR cells treated with the drug. In contrast, JAR cells were more resistant than 143B cells to H2O2-induced cytotoxicity. These results may suggest that cytotoxicity of menadione cannot be explained simply by oxygen free radicals generated from the drug. The resistance of JAR cells to oxygen free radical-induced cytotoxicity may be advantageous for intrauterine fetal life.

Refine search results

Data Stream Classification Using Classifier Ensemble

Aromatic indolinic aminoxyls as antioxidants in cardiac sarcoplasmic reticulum lipid and protein oxidation.

Diversity of the effect of phosphatidylcholine and sphingomyelin on adenylate deaminase from pig brain

Automatic diagnosis of primary headaches by machine learning methods

Kinetic properties of AMP deaminase in acute experimental pancreatitis

Purification and regulatory properties of pig kidney AMP deaminase

Inhibitory effect of 2-hydroxyestradiol on lipid peroxidation in placental microsomes

Dual effect of 2-methoxyestradiol on cell cycle events in human osteosarcoma 143B cells.

A possible involvement of plasma membrane NAD(P)H oxidase in the switch mechanism of the cell death mode from apoptosis to necrosis in menadione-induced cell injury.

Effect of pentoxifylline on proteinuria, markers of tubular injury and oxidative stress in non-diabetic patients with chronic kidney disease - placebo controlled, randomized, cross-over study

Partial characterization of human choriocarcinoma cell line JAR cells in regard to oxidative stress.