Compression of ECG signal is essential especially in the area of signal transmission in telemedicine. There exist many compression algorithms which are described in various details, tested on various datasets and their performance is expressed by different ways. There is a lack of standardization in this area. This study points out these drawbacks and presents new compression algorithm which is properly described, tested and objectively compared with other authors. This study serves as an example how the standardization should look like. Single-cycle fractal-based (SCyF) compression algorithm is introduced and tested on 4 different databases-CSE database, MIT-BIH arrhythmia database, High-frequency signal and Brno University of Technology ECG quality database (BUT QDB). SCyF algorithm is always compared with well-known algorithm based on wavelet transform and set partitioning in hierarchical trees in terms of efficiency (2 methods) and quality/distortion of the signal after compression (12 methods). Detail analysis of the results is provided. The results of SCyF compression algorithm reach up to avL = 0.4460 bps and PRDN = 2.8236%.
- MeSH
- Algorithms * MeSH
- Databases, Factual * MeSH
- Electrocardiography methods MeSH
- Fractals * MeSH
- Data Compression methods MeSH
- Humans MeSH
- Signal Processing, Computer-Assisted MeSH
- Arrhythmias, Cardiac physiopathology MeSH
- Wavelet Analysis MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
The ongoing evolution of microbial pathogens represents a significant issue in diagnostic PCR/qPCR. Many assays are burdened with false negativity due to mispriming and/or probe-binding failures. Therefore, PCR/qPCR assays used in the laboratory should be periodically re-assessed in silico on public sequences to evaluate the ability to detect actually circulating strains and to infer potentially escaping variants. In the work presented we re-assessed a RT-qPCR assay for the universal detection of influenza A (IA) viruses currently recommended by the European Union Reference Laboratory for Avian Influenza. To this end, the primers and probe sequences were challenged against more than 99,000 M-segment sequences in five data pools. To streamline this process, we developed a simple algorithm called the SequenceTracer designed for alignment stratification, compression, and personal sequence subset selection and also demonstrated its utility. The re-assessment confirmed the high inclusivity of the assay for the detection of avian, swine and human pandemic H1N1 IA viruses. On the other hand, the analysis identified human H3N2 strains with a critical probe-interfering mutation circulating since 2010, albeit with a significantly fluctuating proportion. Minor variations located in the forward and reverse primers identified in the avian and swine data were also considered.
Objective.The current practices of designing neural networks rely heavily on subjective judgment and heuristic steps, often dictated by the level of expertise possessed by architecture designers. To alleviate these challenges and streamline the design process, we propose an automatic method, a novel approach to enhance the optimization of neural network architectures for processing intracranial electroencephalogram (iEEG) data.Approach.We present a genetic algorithm, which optimizes neural network architecture and signal pre-processing parameters for iEEG classification.Main results.Our method improved the macroF1 score of the state-of-the-art model in two independent datasets, from St. Anne's University Hospital (Brno, Czech Republic) and Mayo Clinic (Rochester, MN, USA), from 0.9076 to 0.9673 and from 0.9222 to 0.9400 respectively.Significance.By incorporating principles of evolutionary optimization, our approach reduces the reliance on human intuition and empirical guesswork in architecture design, thus promoting more efficient and effective neural network models. The proposed method achieved significantly improved results when compared to the state-of-the-art benchmark model (McNemar's test,p≪ 0.01). The results indicate that neural network architectures designed through machine-based optimization outperform those crafted using the subjective heuristic approach of a human expert. Furthermore, we show that well-designed data preprocessing significantly affects the models' performance.
- MeSH
- Electroencephalography methods MeSH
- Electrocorticography * MeSH
- Humans MeSH
- Neural Networks, Computer * MeSH
- Signal Processing, Computer-Assisted MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
PURPOSE: To evaluate the influence of endovascular therapy of ruptured abdominal or iliac aneurysms on total mortality. MATERIALS AND METHODS: We analyzed the mortality of 40 patients from 2005 to 2009, when only surgical treatment was available. These results were compared with the period 2010 to 2013, when endovascular aneurysm repair (EVAR) was assessed as the first option in selected patients. RESULTS: During 2005 to 2009, the mortality was 37.5%. From 2010 to 2013, 45 patients were treated with mortality 28.9%. Open repair was performed in 35 (77.8%) patients and EVAR in 10 (22.2%) patients. The 30-day and 1-year mortality rates of the EVAR group were 0% and 20%, respectively, and the total mortality rate was 30% during follow-up (median 11 months, range 1-42 months). The 30-day mortality in the surgical group remained unchanged, at 37.1%, and 1-year and total mortality rates were 45.7% and 51.4%, respectively. CONCLUSION: Following integration in the treatment algorithm, EVAR decreased total mortality in our center by 8.6%.
- MeSH
- Algorithms * MeSH
- Aortic Aneurysm, Abdominal diagnosis mortality surgery MeSH
- Iliac Aneurysm diagnosis mortality surgery MeSH
- Aortography methods MeSH
- Time Factors MeSH
- Blood Vessel Prosthesis MeSH
- Blood Vessel Prosthesis Implantation * adverse effects instrumentation mortality MeSH
- Endovascular Procedures * adverse effects instrumentation mortality MeSH
- Delivery of Health Care, Integrated * MeSH
- Critical Pathways MeSH
- Middle Aged MeSH
- Humans MeSH
- Hospitals, University * MeSH
- Tomography, X-Ray Computed MeSH
- Aneurysm, Ruptured diagnosis mortality surgery MeSH
- Retrospective Studies MeSH
- Risk Factors MeSH
- Aortic Rupture diagnosis mortality surgery MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Stents MeSH
- Feasibility Studies MeSH
- Treatment Outcome MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Evaluation Study MeSH
- Comparative Study MeSH
- Geographicals
- Czech Republic MeSH
Interaction with the DNA minor groove is a significant contributor to specific sequence recognition in selected families of DNA-binding proteins. Based on a statistical analysis of 3D structures of protein-DNA complexes, we propose that distortion of the DNA minor groove resulting from interactions with hydrophobic amino acid residues is a universal element of protein-DNA recognition. We provide evidence to support this by associating each DNA minor groove-binding amino acid residue with the local dimensions of the DNA double helix using a novel algorithm. The widened DNA minor grooves are associated with high GC content. However, some AT-rich sequences contacted by hydrophobic amino acids (e.g., phenylalanine) display extreme values of minor groove width as well. For a number of hydrophobic amino acids, distinct secondary structure preferences could be identified for residues interacting with the widened DNA minor groove. These results hold even after discarding the most populous families of minor groove-binding proteins.
- MeSH
- Algorithms MeSH
- Amino Acid Motifs MeSH
- Amino Acids chemistry MeSH
- Arabidopsis metabolism MeSH
- DNA-Binding Proteins metabolism MeSH
- DNA chemistry MeSH
- Phenylalanine chemistry MeSH
- Hydrophobic and Hydrophilic Interactions * MeSH
- Nucleic Acid Conformation MeSH
- Glutamic Acid chemistry MeSH
- Humans MeSH
- Proteins chemistry MeSH
- Saccharomyces cerevisiae metabolism MeSH
- Protein Structure, Secondary MeSH
- Protein Binding MeSH
- Binding Sites MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: Statistical analysis, which has become an integral part of evidence-based medicine, relies heavily on data quality that is of critical importance in modern clinical research. Input data are not only at risk of being falsified or fabricated, but also at risk of being mishandled by investigators. OBJECTIVE: The urgent need to assure the highest data quality possible has led to the implementation of various auditing strategies designed to monitor clinical trials and detect errors of different origin that frequently occur in the field. The objective of this study was to describe a machine learning-based algorithm to detect anomalous patterns in data created as a consequence of carelessness, systematic error, or intentionally by entering fabricated values. METHODS: A particular electronic data capture (EDC) system, which is used for data management in clinical registries, is presented including its architecture and data structure. This EDC system features an algorithm based on machine learning designed to detect anomalous patterns in quantitative data. The detection algorithm combines clustering with a series of 7 distance metrics that serve to determine the strength of an anomaly. For the detection process, the thresholds and combinations of the metrics were used and the detection performance was evaluated and validated in the experiments involving simulated anomalous data and real-world data. RESULTS: Five different clinical registries related to neuroscience were presented-all of them running in the given EDC system. Two of the registries were selected for the evaluation experiments and served also to validate the detection performance on an independent data set. The best performing combination of the distance metrics was that of Canberra, Manhattan, and Mahalanobis, whereas Cosine and Chebyshev metrics had been excluded from further analysis due to the lowest performance when used as single distance metric-based classifiers. CONCLUSIONS: The experimental results demonstrate that the algorithm is universal in nature, and as such may be implemented in other EDC systems, and is capable of anomalous data detection with a sensitivity exceeding 85%.
- Publication type
- Journal Article MeSH
In our paper, we present a performance evaluation of image segmentation algorithms on microscopic image data. In spite of the existence of many algorithms for image data partitioning, there is no universal and 'the best' method yet. Moreover, images of microscopic samples can be of various character and quality which can negatively influence the performance of image segmentation algorithms. Thus, the issue of selecting suitable method for a given set of image data is of big interest. We carried out a large number of experiments with a variety of segmentation methods to evaluate the behaviour of individual approaches on the testing set of microscopic images (cross-section images taken in three different modalities from the field of art restoration). The segmentation results were assessed by several indices used for measuring the output quality of image segmentation algorithms. In the end, the benefit of segmentation combination approach is studied and applicability of achieved results on another representatives of microscopic data category - biological samples - is shown.
- MeSH
- Algorithms * MeSH
- Microscopy * methods MeSH
- Mice MeSH
- Image Processing, Computer-Assisted methods standards MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Evaluation Study MeSH
- Research Support, Non-U.S. Gov't MeSH
BACKGROUND: Clinically significant benign stenoses of the large airways develop in about 1% of patients after intubation. The management of benign stenoses is not unified around the world, nor are there any accepted methods for their screening. OBJECTIVES: The purpose of this study is to describe and compare results of interventional bronchoscopy and surgical therapy of benign stenoses as well as to propose an algorithm for the management of this airways disorder. METHODS: Prospective study on 80 consecutive patients with benign stenoses of the large airways admitted to the Pulmonary Department of the University Hospital of Prague-Motol. RESULTS: Sixty-two patients developed stenoses after endotracheal intubation or tracheostomy, in 18 patients the stenosis was caused by other diseases or pathological situations. Thirty-eight patients were sent for surgical resection of the stenotic part of the airways. 2 surgically treated patients developed recurrence of the stenosis and had to be reoperated on. Narrowing of the trachea at the site of end-to-end anastomosis developed in 6 other patients and was cured by interventional bronchoscopy. The remaining 42 patients were treated by interventional bronchoscopy (Nd-YAG laser, electrocautery, stent) which was curative in 35 patients. Sixty-five patients were alive at the time of evaluation, 15 patients died. Five of them died between 3 and 14 (median 4) months after surgery from a disease other than airway stenosis. Ten nonresected patients also died, with 1 exception, due to a disease other than airway stenosis; the median survival was 9 months. CONCLUSIONS: We recommend to assess the patient for surgery after the initial diagnosis and therapeutic bronchoscopy with dilatation of the stenosis. If the patient is not a suitable candidate for resection, interventional bronchoscopy is an appropriate alternative for the management of benign stenoses of the large airways. Copyright (c) 2005 S. Karger AG, Basel.
- MeSH
- Bronchial Diseases epidemiology etiology therapy MeSH
- Bronchoscopy methods MeSH
- Intubation, Intratracheal adverse effects MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Hospitals, University MeSH
- Prospective Studies MeSH
- Aged MeSH
- Tracheal Stenosis epidemiology etiology therapy MeSH
- Constriction, Pathologic epidemiology etiology therapy MeSH
- Tracheostomy adverse effects MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Geographicals
- Czech Republic MeSH
