47 research outputs found

    Automatic breast-line and pectoral muscle segmentation

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    Pre-processing of mammograms is a crucial step in computer-aided analysis systems. The aim of segmentation is to extract a breast region by estimation of a breast skin-line and a pectoral muscle as well as removing radiographic artifacts and the background of the mammogram. Knowledge of the breast contour also allows further analysis of breast abnormalities such as bilateral asymmetry. In this paper we propose a fully automatic algorithm for segmentation of a breast region, based on two types of global image thresholding: the multi-level Otsu and minimizing the measure of fuzziness as well as the gradient estimation and linear regression. The results of our experiments showed that our method can be used to find a breast line and a pectoral muscle accuratel

    Segmentation of bones in magnetic resonance images of the wrist

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    PURPOSE:   Rheumatoid arthritis (RA) is a disease characterized by progressive and irreversible destruction of bones and joints. According to current recommendations, magnetic resonance imaging (MRI) is used to asses three main signs of RA based on manual evaluation of MR images: synovitis, bone edema and bone erosions. The key feature of a future computer-assisted diagnostic system for evaluation RA lesions is accurate segmentation of 15 wrist bones. In the present paper, we focus on developing a wrist bones segmentation framework. METHOD:    The segmentation procedure consisted of three stages: segmentation of the distal parts of ulna and radius, segmentation of the proximal parts of metacarpal bones and segmentation of carpal bones. At every stage, markers of bones were determined first, using an atlas-based approach. Then, given markers of bones and a marker of background, a watershed from markers algorithm was applied to find the final segmentation. RESULTS:   The MR data for 37 cases were analyzed. The automated segmentation results were compared with gold-standard manual segmentations using a few well-established metrics: area under ROC curve AUC, mean similarity MS and mean absolute distance MAD. The mean (standard deviation) values of AUC, MS and MAD were 0.97 (0.04), 0.93 (0.09) and 1.23 (0.28), respectively. CONCLUSION:   The results of the present study demonstrate that automated segmentation of wrist bones is feasible. The proposed algorithm can be the first stage for the detection of early lesions like bone edema or synovitis

    3D-printed polyester-based prototypes for cosmetic applications—future directions at the forensic engineering of advanced polymeric materials

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    Knowledge of degradation and impairment phenomena of (bio)degradable polymeric materials under operating conditions, and thus the selection of test procedures and prediction of their behavior designates the scope and capabilities as well as possible limitations of both: the preparation of the final product and its durability. The main novelty and objective of this research was to determine the degradation pathways during testing of polylactide and polylactide/polyhydroxyalkanoate materials made with three-dimensional printing and the development of a new strategy for the comprehensive characterization of such complex systems including behavior during waste disposal. Prototype objects were subjected to tests for damage evolution performed under simulating operating conditions. The reference samples and the tested items were characterized by gel permeation chromatography and differential scanning calorimetry to determine changes in material properties. The studies showed that: polyhydroxyalkanoate component during accelerated aging and degradation in environments rich in microorganisms accelerated the degradation of the material; paraffin accelerates polylactide degradation and slows degradation of polyhydroxyalkanoate-based material; under the influence of an environment rich in enzymes, paraffin contamination accelerates biodegradation; under the influence of natural conditions, paraffin contamination slowed degradation; the processing conditions, in particular the printing orientation of individual parts of the container, influenced the material properties in its various regions, affecting the rate of degradation of individual parts.European Regional Development Fun

    Thermal and Mechanical Properties of Microporous Polyurethanes Modified with Reduced Graphene Oxide

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    Microporous polyurethanes (MPU) were modified by adding 0.25%–1.25 wt% of reduced graphene oxide (RGO). The materials were prepared without solvent via in situ polymerization. From a technological point of view, it is very important to obtain functional materials by using reacting compounds only. The thermal characteristics of obtained MPU were investigated using TGA, DSC, and DMA techniques. In comparison to nonmodified microporous polyurethane, the thermal stability and mechanical properties of the modified systems have significantly improved. The temperature corresponding to the maximum degradation rate (Tmax) for nanocomposites containing 1% and 1.25 wt% of RGO was 51°C higher than that observed for pure microporous PU system. The increase of tensile strength was also observed for matrix with the addition of 0.5 wt% RGO nanofiller

    Can we expect re-emergence of infectious diseases in the near future?

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    Ever since Hippocrates expressed the view that environmental factors can influence disease incidence, attempts have been made to link the emergence of disease, especially outbreaks of infectious diseases, with the various factors that contribute to their occurrence. Among the possible causes favoring the spread of pathogens and the increase in the incidence of infectious diseases, environmental and social conditions are mentioned. An unprecedented set of new conditions has made the human population more vulnerable and more susceptible to infectious diseases than ever before. It is possible that the observed contemporary patterns of development and spread of infectious diseases may be seen as heralds of a new stage of epidemiological transformation characterized by an increased risk of infectious disease epidemics. In past centuries, one of the hallmarks of infectious disease plagues has been their unpredictability. Currently, warning forecasts prepared by scientists do not always translate into preventive measures

    Experimental evidence of high pressure decoupling between charge transport and structural dynamics in a protic ionic glass-former

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    In this paper the relaxation dynamics of ionic glass-former acebutolol hydrochloride (ACB-HCl) is studied as a function of temperature and pressure by using dynamic light scattering and broadband dielectric spectroscopy. These unique experimental data provide the first direct evidence that the decoupling between the charge transport and structural relaxation exists in proton conductors over a wide T-P thermodynamic space, with the time scale of structural relaxation being constant at the liquid-glass transition (τα = 1000 s). We demonstrate that the enhanced proton transport, being a combination of intermolecular H+ hopping between cation and anion as well as tautomerization process within amide moiety of ACB molecule, results in a breakdown of the Stokes-Einstein relation at ambient and elevated pressure with the fractional exponent k being pressure dependent. The dT g /dP coefficient, stretching exponent βKWW and dynamic modulus E a /ΔV # were found to be the same regardless of the relaxation processes studied. This is in contrast to the apparent activation volume parameter that is different when charge transport and structural dynamics are considered. These experimental results together with theoretical considerations create new ideas to design efficient proton conductors for potential electrochemical applications

    Pectus Excavatum: A review of current treatment possibilities

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    Anterior chest wall depression known as Pectus excavatum (PE) , is currently the most common congenital chest wall deformation, with incidence estimated at 1/400 births, five times more frequently in boys than girls (5:1 ratio in occurrence). 1 Etiology of this deformity is formed by several hypothesis, including overgrowth of the ribs, developmental failure of the bony thorax or weakness and abnormal flexibility of the sternum. While theoretical concepts of its origin may differ, the common ground is the characteristics of said deformation: a posterior depression of the sternum and the lower costal cartilages. 2Surgical treatment options were described since 1949 with Ravitch procedure and since then a number of new ones has been developed. For many years Ravitch and Nuss procedures were the main way to treat pectus excavatum, with a growing bias towards latter one. Since the Nuss procedure characterizes with less invasive approach and fever overall complications 3 its popularity outgrew Ravitch procedure and currently is described as MIRPE – Minimally Invasive Pectus Excavatum Repair. 4 However afterward then many new techniques were developed, focusing on reducing overall procedure risks, improving patient safety and quality of life and including new technical possibilities. The aim of this study was to gather and evaluate current literature to highlight new treatment options

    Nutrition Strategies for Optimizing Performance and Health in Young Athletes

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    Introduction: The increasing participation of young individuals in sports necessitates a comprehensive understanding of the intricate relationship between nutrition and athletic performance during the critical adolescent years. This introduction sets the stage for an exploration of the dynamic nutritional needs of young athletes, emphasizing the pivotal role of nutrition in supporting growth, energy metabolism, and overall athletic achievement. Current State of Knowledge: The current state of knowledge encompasses an in-depth analysis of key nutritional considerations for young athletes. Examining energy and macronutrient requirements, micronutrient considerations, hydration strategies, and optimal timing of nutrition, this section synthesizes existing research to provide evidence-based guidelines. Furthermore, it addresses the unique challenges posed by different sports and the importance of tailored nutritional approaches for diverse athletic endeavors. The evolving landscape of sports nutrition is also explored, with a specific focus on the benefits and potential risks associated with protein and creatine supplementation. Summary: In summary, this article serves as a comprehensive resource for athletes, coaches, and parents seeking to navigate the intricate intersection of nutrition and young athletes. By elucidating evidence-based strategies and addressing the potential drawbacks and risks associated with certain supplements, the article aims to empower stakeholders with the knowledge needed to make informed decisions regarding the nutritional well-being of young athletes. It underscores the importance of individualized approaches, recognizing the diversity of young athletes and advocating for adaptable nutritional strategies that contribute to both immediate performance gains and sustained health and athletic success

    Alzheimer's Disease - A Comprehensive Review

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    Introduction: Alzheimer's disease (AD) remains a pervasive and challenging neurodegenerative disorder with profound implications for individuals, families, and societies. As the most prevalent cause of dementia globally, AD's prevalence is set to rise significantly in the context of an aging population. This introductory section emphasizes the urgent need for a comprehensive understanding of the disease, encompassing both its molecular intricacies and the socio-economic burden. With age being the primary risk factor, recent research has delved into the complex interplay of genetic predisposition and environmental influences, reshaping our understanding of AD from a multifactorial perspective. Current State of Knowledge: Advancements in Alzheimer's research have led to a nuanced understanding of its pathology. Traditionally characterized by amyloid-beta plaques and tau tangles, recent insights from neuroimaging and biomarker studies have revealed the intricate nature of these pathologies and their roles in disease progression. Genetic studies, including genome-wide association analyses, have identified susceptibility loci, notably the APOE gene. Simultaneously, environmental factors, such as air pollution and lifestyle choices, are recognized contributors to AD risk. The therapeutic landscape has evolved, with ongoing investigations into anti-amyloid and anti-tau therapies, lifestyle interventions, and precision medicine approaches. The synthesis of these diverse findings highlights the dynamic nature of Alzheimer's research and its potential to shape future treatment modalities. Summary: In summary, this article provides a comprehensive overview of the current state of knowledge regarding Alzheimer's disease. From understanding its evolving pathology to exploring the interplay of genetic and environmental factors, the multifactorial nature of AD is underscored. The therapeutic landscape is actively advancing, presenting a hopeful outlook for future treatments. &nbsp

    The terror of athletes - Anterior Cruciate Ligament Reconstruction, grafts and moden techniques

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    Introduction The anterior cruciate ligament (ACL) is a prevalent sports-related injury, constituting nearly half of knee injuries. This narrative review explores the evolution of ACL reconstruction surgeries, emphasizing graft types and their pros and cons. Current state of knowledgeThe ideal ACL graft choice depends on factors like age, lifestyle, and demands. Autografts are the current standard, with the Quadriceps Tendon graft offering similar outcomes and fewer complications. Allografts are a secondary option for older, low-demand patients due to a shorter recovery period. Artificial grafts have limited use, lacking strong evidence for clinical advantages but may be considered for suturing torn ACL stumps and in cases were quick recovery is essential. Summary Contemporary orthopedic practitioners must possess comprehensive knowledge of various ACL reconstruction graft types to tailor interventions precisely to individual patient requirements. The selection of a graft should be rooted in a profound comprehension of patients' lifestyles, medical histories, and specific demands, thereby mitigating the subjective impact of any associated limitations for the patient
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