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Dive into the research topics where Zbigniew M. Wawrzyniak is active.

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Featured researches published by Zbigniew M. Wawrzyniak.


Photonics applications in astronomy, communications, industry, and high-energy physics experiments. COnference | 2005

Rhinomanometry in nasal cavity respiratory resistance measurement

Piotr Rapiejko; Andrzej Wojdas; Zbigniew M. Wawrzyniak; Beata Zielik-Jurkiewicz

The authors present rhinomanometry as a method for nasal cavity respiratory resistance measurement on the basis of results from 185-patients study group and 30 persons control group. Thanks to the results from this study we estimated normal respiratory resistance oscillation and effectiveness of different surgical methods, that improve nasal patency.


Photonics Applications in Astronomy, Communications, Industry, and High-Energy Physics Experiments 2012 | 2012

Simplified model of mean double step (MDS) in human body movement

Jacek J. Dusza; Zbigniew M. Wawrzyniak; C.Fernando Mugarra González

In this paper we present a simplified and useful model of the human body movement based on the full gait cycle description, called the Mean Double Step (MDS). It enables the parameterization and simplification of the human movement. Furthermore it allows a description of the gait cycle by providing standardized estimators to transform the gait cycle into a periodical movement process. Moreover the method of simplifying the MDS model and its compression are demonstrated. The simplification is achieved by reducing the number of bars of the spectrum and I or by reducing the number of samples describing the MDS both in terms of reducing their computational burden and their resources for the data storage. Our MDS model, which is applicable to the gait cycle method for examining patients, is non-invasive and provides the additional advantage of featuring a functional characterization of the relative or absolute movement of any part of the body.


Experimental Diabetes Research | 2017

Retinal Photoreceptors and Microvascular Changes in Prediabetes Measured with Adaptive Optics (rtx1™): A Case-Control Study

Anna Zaleska-Żmijewska; Paweł Piątkiewicz; Barbara Śmigielska; Anna Sokołowska-Oracz; Zbigniew M. Wawrzyniak; Dorota Romaniuk; Jerzy Szaflik; Jacek P. Szaflik

Background Patients with prediabetes are at risk for diabetes, cardiovascular events, and microvascular complications. The rtx1 (Imagine Eyes, France) permits early detection of changes in the retinal photoreceptors and vessels. Objective Cone parameters and retinal microvasculature were analyzed with the rtx1 in 12 prediabetic patients and 22 healthy subjects. The analysis was based on cone density (DM), interphotoreceptor distance (SM), cone packing regularity, and retinal vessel parameters: wall thickness, lumen diameter (LD), wall-to-lumen ratio (WLR), and cross-sectional area of the vascular wall. Results DM in the prediabetic group was not significantly lower than that in the control group (18,935 ± 1713 cells/mm2 and 19,900 ± 2375 cells/mm2, respectively; p = 0.0928). The LD and WLR means differed significantly between the prediabetic and the control groups (LD 94.3 ± 10.9 versus 101.2 ± 15, p = 0.022; WLR 0.29 ± 0.05 versus 0.22 ± 0.03, p < 0.05). A multivariate regression analysis showed that the WLR was significantly correlated with BMI and total cholesterol. Conclusions Abnormalities found in rtx1 examinations indicated early signs of arteriolar dysfunction, prior to impaired glucose tolerance progressing to diabetes. The rtx1 retinal image analysis offers noninvasive measurement of early changes in the vasculature that routine clinical examination cannot detect.


Medicine | 2017

Is atrial fibrillation a risk factor for normal-tension glaucoma?

Anna Zaleska-Żmijewska; Maciej Janiszewski; Zbigniew M. Wawrzyniak; Marek Kuch; Jerzy Szaflik; Jacek P. Szaflik

Abstract Glaucoma (GL) and atrial fibrillation (AF) are diseases of significant social importance. Cardiovascular disorders such as systemic hypertension, hypotension, increased blood viscosity, vasospasm, and diabetes are potential risk factors of GL, especially when intraocular pressure is not elevated. Only a few studies have reported a possible connection between cardiac arrhythmias and GL. The purpose of this study was to evaluate the risk of GL in patients with AF. A total of 117 patients were included in the study, 79 with AF (AF group) and 38 with sinus rhythm (Control group), matched for age and sex. The mean ± standard deviation age was 73.6 ± 7.2 and 71.6 ± 4.7 years for the AF and control groups, respectively. There were no statistically significant differences in the percentage of systemic hypertension, congestive heart failure, diabetes mellitus type 2, or vascular disease between the groups. Patients were examined for the presence of normal-tension glaucoma (NTG) by an ophthalmologist. NTG was confirmed in 40 patients (34.2%) in the entire group, with 35 (44.3%) in the AF group and 5 (13.15%) in the Control group. The incidence of NTG was significantly higher in the AF group (P = .0221). Women represented 60% of GL patients in the AF group and 80% in the control group. There were no significant differences in intraocular pressure between the groups (mean ± standard deviation, 14.3 ± 2.3 vs. 14.2 ± 2.8 mmHg, P = .4202). Approximately three-fourths of patients with AF and NTG had early visual field damage based on the Hodapp classification. AF, independent of other known cardiovascular risk factors, increases the risk of developing NTG. Many AF patients do not have conspicuous symptoms of GL, so understanding the possible risk of its development is critical because early detection might help to prevent later visual impairment and even irreversible blindness.


Medicine | 2016

Diagnosis of hepatitis C virus infection in pregnant women in the healthcare system in Poland: Is it worth the effort?

Bożena Walewska-Zielecka; Urszula Religioni; Grzegorz Juszczyk; Aleksandra Czerw; Zbigniew M. Wawrzyniak; Piotr Soszyński

AbstractThe hepatitis C virus (HCV) is globally recognized as a serious public health concern. Current statistics indicate that approximately 2% of people worldwide and 1.9% of people in Poland suffer from HCV infection.This study was conducted to assess the anti-HCV seroprevalence in pregnant women in Poland and subsequently provide recommendations on the rationale for obligatory screening.A total of 42,274 women participated in our study, of which 16,130 were pregnant. We were granted access to their health data stored in the form of electronic medical records kept by the network of outpatient clinics throughout Poland.The lowest rate of positive anti-HCV test results was found in women ages 25 to 34 (0.73%); however, younger and older age groups had similar rates (15–24 = 0.86%; 35–44 = 0.84%). Additional analysis of data from the period between 2011 and 2014 revealed a downward trend in the proportion of positive anti-HCV tests among pregnant women (mean positive anti-HCV = −0.001 × year + 1.9451; R2 = 0.7274). Regardless of the gradual increase in the number of female patients undergoing screening between 2004 and 2015, there has been a constant decrease in the rate of positive cases. The rate of pregnant women potentially infected with HCV was twice as lower than that in a control group of women undergoing tests for other medical circumstances: 0.76% vs 1.67% (P < 0.0001).Analysis of real-world data of female patients in Poland provides evidence that screening based on an individuals medical history and behavioral risk factors in clinical circumstances would be more effective than obligatory testing of all pregnant women.


XXXVI Symposium on Photonics Applications in Astronomy, Communications, Industry, and High-Energy Physics Experiments (Wilga 2015) | 2015

Layer measurement in high frequency ultra-sonography images for skin

Zbigniew M. Wawrzyniak; Michał Szyszka

In this paper, the problem of automatic determination of the position and measuring the thickness of the human skin layers in high-frequency ultrasound images (HFUS) is solved. Location and the process of position determination of the skin layers are not an obvious process due to the phenomenological nature of the images received in HFUS, the so-called speckle noise and the lack of the objective measures. In order to determine the positions of the boundaries of the skin layers, the image analysis methods were used, based on the specific features of the HFUS images, such as layered structure and echogenicity features. Only the fusion of the results of the analysis algorithms based on global (histogram of intensity levels) and local image features (cross-sectional and topological characteristics) improves discriminative features applicable to complete the information about the properties of the HFUS images with layered structure and to develop a method assessing the thickness of the skin layers. The knowledge gathered from such layers checks can improve understanding of the nature of the human skin and provide a more objective conditions for HFUS diagnostic imaging with speeding up the diagnostic process for dermatologists. We proposed a new method for automatic segmentation on HFUS images using fusion of discriminative information based on nonlinear segmentation with a reasonable threshold setting, boundary selecting and linking, and false boundary point removing strategies for intensity distributions.


Photonics Applications in Astronomy, Communications, Industry, and High-Energy Physics Experiments 2013 | 2013

ICT use for information management in healthcare system for chronic disease patient

Zbigniew M. Wawrzyniak; Mira Lisiecka-Biełanowicz

Modern healthcare systems are designed to fulfill needs of the patient, his system environment and other determinants of the treatment with proper support of technical aids. A whole system of care is compatible to the technical solutions and organizational framework based on legal rules. The purpose of this study is to present how can we use Information and Communication Technology (ICT) systemic tools in a new model of patient-oriented care, improving the effectiveness of healthcare for patients with chronic diseases. The study material is the long-term process of healthcare for patients with chronic illness. Basing on the knowledge of the whole circumstances of patient’s ecosystem and his needs allow us to build a new ICT model of long term care. The method used is construction, modeling and constant improvement the efficient ICT layer for the patient-centered healthcare model. We present a new constructive approach to systemic process how to use ICT for information management in healthcare system for chronic disease patient. The use of ICT tools in the model for chronic disease can improve all aspects of data management and communication, and the effectiveness of long-term complex healthcare. In conclusion: ICT based model of healthcare can be constructed basing on the interactions of ecosystem’s functional parts through information feedback and the provision of services and models as well as the knowledge of the patient itself. Systematic approach to the model of long term healthcare assisted functionally by ICT tools and data management methods will increase the effectiveness of patient care and organizational efficiency.


ieee international workshop on imaging systems and techniques | 2007

Improvement in Minutiae Detection by Single Ridge Local Analysis for Fingerprint Image Processing

Marcin Jędryka; Zbigniew M. Wawrzyniak

This paper concerns algorithms related to analysis of fingerprint images and can be useful in the areas of image preprocessing and fingerprint matching based on extraction of minutiae. Algorithms are based on efficient application of detailed information about ridges in fingerprint patterns. The main goal of this algorithm is to optimize the so called ridge-following algorithm in grayscale images for detection of minutiae. Proposed modifications make use of local characteristic features from patterns of neighboring parallel ridges in order to minimize probability of skipping over ridges in a process of segmentation of a single ridge. This is a crucial problem in analysis of low quality images acquisited from a real sensor. The method shows to be efficient in proper minutiae detection together with other methods in fingerprint image processing. The solution of the use of local characteristic features proved to be useful also for filtration and segmentation of fingerprint images.


Photonics Applications in Astronomy, Communications, Industry, and High-Energy Physics Experiments 2018 | 2018

Averaged EMG signal models obtained in cyclic processes

Monika Selegrat; Jacek J. Dusza; Zbigniew M. Wawrzyniak

The main aim of this paper is to verify an objective method of averaging electromyographic signals for cyclic processes, which are presented on Symposium Wilga 2016 [1]. The process of creating an objective EMG signal model will be considered. The filtration, the method of smoothing the signal, the sequence of actions and the way they were carried out were taken into account. It is also attempts to measure and analyze the electromyographic signals obtained from the muscles of the lower limbs during the cyclic activity of walking with different loads. This research is based on the data collected in the Laboratory of Movement Analysis at the Medical University of Warsaw. The object of research was a healthy man in the age of 35. Based on the collected data, 130 objective EMG models were created. They correspond to ten muscles of the lower limbs. There were 13 different models calculated for each muscle, corresponding to its activity during the unloaded gait cycle and with left-, right- and double-sided loading for 2,4,6 and 8 kg. The signal models created in this way became the basis for the analysis, as a function of the load, of certain parameters of EMG signals generated during the walk. For each of the EMG signal models, the following parameters were calculated: a moment of muscle activation, duration of muscle activation, physiological costs incurred during muscle activation. Collected data could compere muscle activities and calculate the phases of their interactions.


Annals of Agricultural and Environmental Medicine | 2018

The association between paracetamol use and the risk of asthma, rhinitis and eczema in the Polish population

Agnieszka Lipiec; Zbigniew M. Wawrzyniak; Adam J. Sybilski; Urszula Samolińska-Zawisza; Edyta Krzych Fałta; Barbara Piekarska; Grażyna Dulny; Bożenna Stankiewicz Choroszucha; Filip Raciborski; Bolesław Samoliński

INTRODUCTION A growing number of epidemiological studies suggest that paracetamol, which is commonly used in children, may be a risk factor for asthma, allergic rhinitis, and atopic eczema. OBJECTIVE The aim of this study was to determine and characterize the correlation between paracetamol use and asthma, allergic rhinitis, and atopic eczema symptoms in the Polish population. MATERIAL AND METHODS The study is part of the ECAP project involving the use of the ISAAC and ECRHS questionnaires. Completed questionnaires of 18,617 subjects, including 10,011 (53.8%) females, were analyzed. Children aged 6-7 (n=4,510), adolescents aged 13-14 (n=4,721), and adults aged 20-44 (n=9,386) constituted 24.2%, 25.4%, and 50.4% of respondents, respectively. Study subjects lived in 8 major urban centres and one rural area. The frequency of paracetamol use during the previous 12 months and symptoms of asthma, allergic rhinitis, and atopic eczema during that period were analyzed. RESULTS The use of paracetamol was associated with a significant dose-dependent increase in the risk of asthma symptoms in all evaluated age groups. This was demonstrated via odds ratios (OR) for developing asthma symptoms, including wheezing or whistling in the chest in 6-7-year-olds and exercise-induced shortness of breath in 13-14-year-olds and adults, depending on the frequency of paracetamol use in the previous 12 months, compared to no paracetamol intake during that period. CONCLUSIONS The use of paracetamol in the last 12 months was associated with a significant dose-dependent increase in the risk of rhinitis and skin allergy symptoms, as demonstrated by the odds ratio. Therefore, frequent paracetamol use may be a risk factor for symptoms of asthma, rhinitis, and skin allergy in the Polish population.

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Adam Majewski

Warsaw University of Technology

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Agnieszka Lipiec

Medical University of Warsaw

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Daniel Paczesny

Warsaw University of Technology

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Jacek J. Dusza

Warsaw University of Technology

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Jacek P. Szaflik

Medical University of Warsaw

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Jerzy Szaflik

Medical University of Warsaw

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Aleksandra Czerw

Medical University of Warsaw

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Artur Dybko

Warsaw University of Technology

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