Comptes Rendus De L Academie Bulgare Des Sciences最新文献

{"title":"Texture Analysis of Adenomatous and Metastatic Adrenal Lesions on Native and Contrast-enhanced Computed Tomography","authors":"Magdalena Belyanova, Martin Krupev","doi":"10.7546/crabs.2023.10.16","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.16","url":null,"abstract":"Differentiating lipid-poor adrenal adenomas from adrenal metastases is not possible without performing a dedicated contrast-enhanced CT (CECT) protocol. Our purpose is to evaluate the possible role of texture analysis in classifying adrenal lesions.
 This is a retrospective study. We evaluated 33 patients with 47 metastases and 43 patients with 47 adenomas. Seven of the adenomas were lipid-poor, and the rest – lipid-rich adenomas. We used commercially available software for lesion segmentation and texture analysis on native and arterial phase CT images with a slice thickness of 2 mm. The segmentation was semi-automated, and features were computed on the resulting regions of interest (ROI) for each lesion on both native and arterial phases. Two conventional (HU standard deviation, Histogram Entropy) and six second-order texture features (GLCM – Homogeneity, Energy, Entropy log 10, Contrast, Dissimilarity, NGDLM–Busyness) were calculated. For statistical analysis the IBM SPSS 19 package was used to compare the following groups in both phases: 1. Adenomas--Metastasis; 2. Lipid-rich adenomas (LRA)--metastases; 3. Lipid-rich--lipid-poor adenomas (LPA); 4. Lipid-poor adenomas--metastases.
 There was a statistically significant difference in the distribution of some conventional (Histogram Entropy) and second-order features (GLCM – Homogeneity, Energy, Entropy log 10, Dissimilarity) in the first group on the native as well as on the enhanced images. The results were similar when comparing lipid-rich adenomas to metastases. Only native phase derived features were discriminative between lipid-rich and lipid-poor adenomas, with no difference between parameters on CECT. No difference was found between any of the texture features in lipid-poor adenomas and metastases for both phases.
 First- and second-order texture features were graded based on their potential for serving as classifier tools. Unenhanced features ranked higher. Further research and validation are needed to discover the most robust set of features for differentiating between lipid-poor adenomas and metastases.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"4 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135872437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Three-link Gravity-balanced Mechanism for Operating Room Assistance","authors":"Onur Denizhan","doi":"10.7546/crabs.2023.10.11","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.11","url":null,"abstract":"The compensation of gravity is not a new problem and gravity-balanced mechanisms have been extensively studied. Some of these studies present practical applications of the gravity-balanced mechanisms, while others focus on the theoretical modelling of the mechanism. In this study, a practical application, a gravity-balanced planar robotic manipulator for operating room assistance is presented. In this design, an auxiliary parallelogram with two linear springs is utilized to accomplish gravity compensation. As a passive gravity-balanced mechanism, it does not have any actuators. The novelty of the mechanism is the exchangeable end-effector and changeable spring attachment location accordingly. The simulation results show that the designed mechanism is gravity-balanced in all configurations. The presented mechanism in this study can also be extended to solve a multi-link gravity balance problem.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"198 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135814071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Iron Metabolism Dysregulation and Atherosclerotic Changes in Obstructive Sleep Apnoea","authors":"Victor Manolov, Ognian Georgiev, Vasil Vasilev, Radoslava Emilova, Iulia Petrova, Savina Hadjidekova, Georgi Angov, Todor Kunchev, Kamen Tzatchev, Latchezar Traykov, Ventsislava Pencheva","doi":"10.7546/crabs.2023.10.17","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.17","url":null,"abstract":"The Syndrome of obstructive sleep apnoea (OSA) is associated with an increased risk of arterial hypertension, metabolic syndrome, diabetes mellitus type 2, brain-vascular damages and atherosclerosis. The aim of this study is to assess the connection between iron metabolism dysregulation in OSA and atherosclerotic changes of carotid arteries. Thirty-five OSA patients with brain-vascular atherosclerotic evidences were included in this study; changes were evaluated by carotid artery intima-media thickness (IMT) and flow-mediated dilatation (FMD). Their results were compared to an equal number of healthy volunteers. Haematological and biochemical assays were performed in all participants in the study. Serum hepcidin levels are statistically significantly increased in OSA patients with atherosclerotic a. carotis changes (101.9±10.1 µg/L) compared to the control group (18.5±2.5 µg/L); $$P<0.001$$. Serum homocysteine levels are significantly higher in OSA than in healthy people. Average IMT (1.22±0.19) and ABI (1.71±0.14) values in OSA patients with atherosclerotic a. carotis changes are increased in comparison to the control group (0.34±0.07, 1.11±0.06, resp.); $$P<0.001$$. Serum vitamin B12 levels were lower in OSA patients with atherosclerotic changes in carotid arteries (71.7±9.9 pmol/L) compared to the controls (449.7±21.4 pmol/L); $$P<0.001$$. A connection between iron homeostasis and atherosclerotic changes was established during this study. Increased hepcidin and homocysteine concentrations might be connected to an elevated risk of cardio- and brain-vascular diseases in OSA. The use of these markers in the routine practice may be very useful for early atherosclerosis assessment in OSA.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135871733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance of Selective Plated Copper Coatings on Stainless Steel 316L and Nickel Alloy Ni201: Microstructure, Microhardness, Wear Resistance, and Corrosion Resistance","authors":"Deyan Veselinov, Hristo Skulev, Radostina Yankova, Veneta Koeva","doi":"10.7546/crabs.2023.10.12","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.12","url":null,"abstract":"This study investigates the properties and performance of selective plated copper coatings on stainless steel 316L and nickel alloy Ni201 substrates, using acidic and alkaline electrolyte solutions. The analysis encompasses surface microstructure, elemental distribution, microhardness, surface roughness, wear resistance, and corrosion resistance of the coatings. The results demonstrate that the selective plated copper coatings exhibit a uniform and continuous deposition, free from visible irregularities or structural imperfections. Notably, the alkaline copper coatings exhibit significantly higher microhardness values compared to the acidic coatings, irrespective of the substrate materials. Surface roughness measurements reveal an increase in roughness after wear testing for all coatings, with the alkaline coatings showing lower initial roughness values and superior wear resistance compared to the acidic coatings. Concerning corrosion resistance, the alkaline copper coatings display a higher susceptibility to corrosion compared to the acidic coatings. Generally, the findings underscore the effectiveness of the selective plating process in producing high-quality, uniform, and defect-free copper coatings on stainless steel and nickel alloy substrates.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135872795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and Implementation of Modified Multilevel Inverter FED BLDC Motor for Electric Vehicle Application","authors":"Murugesan Manivel, Lakshmi Kaliappan","doi":"10.7546/crabs.2023.10.10","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.10","url":null,"abstract":"In this work a modified hybrid multilevel inverter with reduced device is proposed. The system considerably reduces the quantity of power electronic power switches to twenty-one so as to create fifteen level three phase output, whereas conventional structures require higher number of power devices. Higher number of power switches leads to increased distortion, losses and cost. The recommended circuit gives better response, higher efficiency, reduced cost, high reliability and fault tolerance. Decrease in number of power switches, intensely diminishes the convolution of the switching circuitry.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"25 36","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135863764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative Evaluation of Spectra and Intensity of Anomalous Cosmic Rays in Middle Atmosphere","authors":"Peter Velinov, Simeon Asenovski, Lachezar Mateev","doi":"10.7546/crabs.2023.10.08","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.08","url":null,"abstract":"The influence of Anomalous Cosmic Rays (ACRs) on ionization in the boundary of the ionosphere-middle atmosphere system (40–50 km) is investigated, taking into account the spectrum, intensity, geomagnetic, and atmospheric cut-offs. The ACR spectra and intensity in the middle atmosphere are determined using&#x0D; the CORSIMA (COsmic Ray Spectra and Intensity in Middle Atmosphere) model. ACR spectra are presented for various atmospheric altitudes within the range of 40–50 km, with the lower boundary of the ionosphere at approximately 50 km. Experimental satellite measurements are utilized for the main ACR constituents, including Hydrogen (protons), Helium, Nitrogen, and Oxygen nuclei. It is found that the influence of ACRs extends to the polar cap regions above 65°–70° geomagnetic latitude, and certain ACR ionization rate values in these regions are comparable to Galactic Cosmic Ray (GCR) ionization rates. Future studies will also consider Multiply Charged Anomalous Cosmic Rays (MCACRs), which exhibit similar differential spectra to the singly ionized ACR components addressed in this study.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135872773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Additive Effects of Helix aspersa Mucus Fractions with Chemotherapy Drugs in Breast Cancer: Exploring Anti-proliferative Potential","authors":"Zlatina Vlahova, Alexander Tzintzarov, Maria Petrova, Alexander Dushkov, Lyudmila Velkova, Aleksandar Dolashki, Pavlina Dolashka, Iva Ugrinova","doi":"10.7546/crabs.2023.10.04","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.04","url":null,"abstract":"This study investigated the anti-proliferative effects of biologically active substances (BAS) derived from the mucus of the garden snail Helix aspersa on breast cancer cell lines (MCF-7 and MDA-MB-231) and a non-cancerous cell line (MCF-10A). Two mucus fractions with different molecular weights (Mw) were examined, and their interactions with the chemotherapy drugs cisplatin and tamoxifen were evaluated.&#x0D; The results showed that the mucus fractions exhibited a slight anti-proliferative effect on breast cancer cells, with the fraction having Mw above 50 kDa demonstrating stronger activity compared to the fraction with Mw above 20 kDa. Furthermore, the combination of the mucus fractions with cisplatin or tamoxifen resulted in significant reductions in the half effective dose, indicating possible synergistic effects which were more pronounced with the fraction having Mw above 20 kDa. Dose-response curves and microscopic images supported the presence of such effects, revealing lower IC50 values and significant cell death when the cancer cells were treated with the combination of the mucus fractions and chemotherapy drugs. However, the analysis using the (highest single agent) HSA model indicated mostly additive interactions between the mucus fractions and chemotherapy drugs.&#x0D; These findings suggest the potential of biologically active substances derived from Helix aspersa mucus in enhancing the anti-proliferative effects of chemotherapy drugs in breast cancer treatment. The identification of additive interactions provides insights into the development of combination therapies with reduced drug dosage. Overall, this study contributes to the understanding of the anti-proliferative effects of Helix aspersa mucus fractions and their interactions with chemotherapy drugs, highlighting their potential as novel therapeutic approaches in breast cancer treatment.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135870133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MiRNA Expression Profiles in an Ectopic Endometrium of Patients at Different Stage of Endometriosis","authors":"Victoria Spasova, Vesela Karamisheva, Zora Hammoudeh, Olga Antonova, Radoslav Todorov, Liliya Koleva, Anatoli Kolev, Rada Staneva, Draga Toncheva, Savina Hadjidekova","doi":"10.7546/crabs.2023.10.14","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.14","url":null,"abstract":"Endometriosis is a debilitating disease that affects up to 15% of women worldwide. Delayed diagnosis, lack of noninvasive biomarker and unexplained pathogenesis are key problems for specialists and patients alike. MiRNAs are a class of noncoding RNAs that regulate myriad of cellular functions. These gene expression regulators may prove to be attractive biomarkers with diagnostic and prognostic value for endometriosis.&#x0D; Tissue samples were collected from the participants enrolled in the study during laparoscopy (patients) and hysteroscopy (control group). After RNA isolation (miRNeasy MiniKit, Qiagen) based on the disease stage, three pools – each containing 15 RNA samples, were constructed: 1) early stage endometriosis, 2) late stage endometriosis, and 3) healthy controls. Each pool sample was subjected to reverse transcription via miScript II RT Kit, Qiagen to obtain cDNA. SYBR Green based Real-time PCR assay was used to determine the expression profile of 84 miRNAs (Human miFinder miRNA PCR Array, Qiagen).&#x0D; We detected 32 differently expressed miRNAs between early stage endometriosis and control group, and 51 differently expressed miRNAs between advanced stage endometriosis and control group. Three miRNAs were differentially expressed with more than 10-fold change in the early stage group and thn miRNAs showed more than 10-fold change in the advanced stages group. The three miRNAs with the highest fold change in the expression levels in both case groups were nominated as potential biomarkers for endometriosis. The results of the analysis of their target genes supports the role of deregulation of apoptosis, angiogenesis, epithelial-mesenchymal transition, and various other cellular signalling pathways in endometriosis development.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135870859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep Learning-based Precision Diagnosis of Lung Diseases on the Internet of Medical Things (IoMT)","authors":"Lekshmy Sushama, Kuttaiyur Sridhar, Michaelraj Roberts","doi":"10.7546/crabs.2023.10.07","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.07","url":null,"abstract":"Lung disease is one of the common and severe pathological conditions that affect the respiratory system, causing respiratory illness and potential mortality. In recent times, deep learning paradigm based on the Internet of Medical Things (IoMT) platform has been adopted as a viable solution to address the challenges encountered in detection of lung diseases which are characterized by their diverse nature and the complexities associated with their diagnosis. In this work, we have proposed an approach that aims to achieve accurate prediction and analysis of lung diseases. The proposed research methodology presents a Deep Learning-based Accurate Lung Disease Prediction (DL-ALDP) model based on deep learning algorithms to enhance its predictive capabilities. The DL-ALDP framework integrates several preprocessing techniques, including Wiener filtering, optimized region growing method (ORGM)-based feature extraction, and Contrast limited AHE (CLAHE)-based segmentation. The accurate prediction of lung diseases is achieved by utilizing a Deep Neural Network (DNN) for classification purposes. The DL-ALDP technique, as suggested, attained a precision of 86.77%, sensitivity of 82.47%, specificity of 92.87%, accuracy of 92.08%, and F1 score of 89.42%. The findings of this research underscore the prospective utility of deep learning techniques in forecasting and analyzing lung ailments within the context of the IoMT platform. Through IoMT capabilities, healthcare practitioners can avail themselves of enhanced prognostic accuracy and timeliness, resulting in superior patient care and outcomes.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"55 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135870868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonexistence of Global Solutions to Double Dispersion Equations with Linear Restoring Force and Nonlinearities with Variable Coefficients","authors":"Natalia Kolkovska, Milena Dimova, Nikolay Kutev","doi":"10.7546/crabs.2023.10.02","DOIUrl":"https://doi.org/10.7546/crabs.2023.10.02","url":null,"abstract":"We investigate Cauchy problem to double dispersion equations with polynomial type nonlinearities with variable coefficients. Necessary and sufficient conditions for nonexistence of global weak solutions and nonblowing up ones are found for subcritical initial energy. For supercritical energy a sufficient condition for finite time blow up of the weak solutions, independent of the scalar product of the initial data, is developed.","PeriodicalId":50652,"journal":{"name":"Comptes Rendus De L Academie Bulgare Des Sciences","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135871035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}