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Many factors and molecular pathways are involved in the pathogenesis of arterial hypertension. The increase in blood pressure may be determined by the properties of specific gene products and their associated action with environmental factors. In recent years, much attention has been paid to the Wnt/β-catenin signaling pathway which is essential for organ damage repair and homeostasis. Deregulation of the activity of the Wnt/β-catenin pathway may be directly or indirectly related to myocardial hypertrophy, as well as to cardiomyocyte remodeling and remodeling processes in pathological states of this organ. There are reports pointing to the role of the Wnt/β-catenin pathway in the course and development of organ complications in conditions of arterial hypertension. This paper presents the current state of knowledge of the role of the Wnt/β-catenin pathway in the regulation of arterial pressure and its impact on the physiology and the development of the complications of arterial hypertension in the heart. [ABSTRACT FROM AUTHOR]

Encoding data visually is at the heart of visualization. We usually assume that encodings are read as specified (i.e., if a bar chart is drawn by the length of the bars based on the data, that is also how we read them). In this paper, we question this assumption and demonstrate that observed encodings often differ from the ones used to specify the visualization. The value of a chart also often comes from higher level derived encodings, and which encodings end up getting used also depends on the user's task. [ABSTRACT FROM AUTHOR]

Background and Aim: Enhanced Recovery After Surgery (ERAS) protocols are a series of perioperative interventions well-established in improving the care and outcomes of patients. With recent emergence of studies on its implementation in cardiac surgery, this paper represents the first systematic review on current evidence of ERAS efficacy in this field. Methods: Two reviewers independently searched through Pubmed, Cochrane, Google Scholar, Web of Science, Embase and Scopus. Comparative studies with controls that described the implementation of ERAS in all types of cardiac operations from 2001 to 2020 were included. Data extracted included patient demographics, components of ERAS protocol described, types of cardiac surgery, and postoperative outcomes. Results: In the final analysis, nine studies were included, of which there were one randomized controlled trial (RCT), one quasi-experiment and seven retrospective/prospective studies. Significant improvement in hospital and ICU length of stay, as well as reduction in postoperative opioid consumption were demonstrated. No increase in postoperative complications were reported. Conclusion: ERAS in cardiac surgery has shown to be potentially safe and effective in improving certain postoperative outcomes. However, the evidence is limited by the lack of high-quality RCTs. We also found the lack of practice of class 1 recommended interventions set forth by the ERAS Cardiac Society. Furthermore, majority of studies only evaluated the immediate postoperative outcomes of patients, and not the long-term outcomes. RCTs that fully implement measures recommended by the ERAS Cardiac Society, with assessments on both immediate and long-term outcomes, are warranted. [ABSTRACT FROM AUTHOR]

To extend the preservation of donor hearts beyond the current 4–6 h, this paper explores heart cryopreservation by vitrification—cryogenic storage in a glass‐like state. While organ vitrification is made possible by using cryoprotective agents (CPA) that inhibit ice during cooling, failure occurs during convective rewarming due to slow and non‐uniform rewarming which causes ice crystallization and/or cracking. Here an alternative, "nanowarming", which uses silica‐coated iron oxide nanoparticles (sIONPs) perfusion loaded through the vasculature is explored, that allows a radiofrequency coil to rewarm the organ quickly and uniformly to avoid convective failures. Nanowarming has been applied to cells and tissues, and a proof of principle study suggests it is possible in the heart, but proper physical and biological characterization especially in organs is still lacking. Here, using a rat heart model, controlled machine perfusion loading and unloading of CPA and sIONPs, cooling to a vitrified state, and fast and uniform nanowarming without crystallization or cracking is demonstrated. Further, nanowarmed hearts maintain histologic appearance and endothelial integrity superior to convective rewarming and indistinguishable from CPA load/unload control hearts while showing some promising organ‐level (electrical) functional activity. This work demonstrates physically successful heart vitrification and nanowarming and that biological outcomes can be expected to improve by reducing or eliminating CPA toxicity during loading and unloading. [ABSTRACT FROM AUTHOR]

Direct cardiac reprogramming, which refers to somatic cell (i.e. fibroblast) fate conversion to cardiomyocyte-like cell without transitioning through an intermediate pluripotent state, provides a novel therapeutic strategy for heart regeneration by converting resident cardiac fibroblasts to cardiomyocytes in situ. However, several limitations need to be addressed prior to clinical translation of this technology. They include low efficiency of reprogramming, heterogeneity of starting fibroblasts, functional immaturity of induced cardiomyocytes (iCMs), virus immunogenicity and toxicity, incomplete understanding of changes in the epigenetic landscape as fibroblasts undergo reprogramming, and the environmental factors that influence fate conversion. Several studies have demonstrated that a combination of enforced expression of cardiac transcription factors along with certain cytokines and growth factors in the presence of favorable environmental cues (including extracellular matrix, topography, and mechanical properties) enhance the efficiency and quality of direct reprogramming. This paper reviews the literature on the influence of the microenvironment on direct cardiac reprogramming in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Objective: Catheters and wires are used extensively in cardiac catheterization procedures. Detecting their positions in fluoroscopic X-ray images is important for several clinical applications such as motion compensation and co-registration between 2D and 3D imaging modalities. Detecting the complete length of a catheter or wire object as well as electrode positions on the catheter or wire is a challenging task. Method: In this paper, an automatic detection framework for catheters and wires is developed. It is based on path reconstruction from image tensors, which are eigen direction vectors generated from a multiscale vessel enhancement filter. A catheter or a wire object is detected as the smooth path along those eigen direction vectors. Furthermore, a real-time tracking method based on a template generated from the detection method was developed. Results: The proposed framework was tested on a total of 7,754 X-ray images. Detection errors for catheters and guidewires are 0.56 ± 0.28 mm and 0.68 ± 0.33 mm, respectively. The proposed framework was also tested and validated in two clinical applications. For motion compensation using catheter tracking, the 2D target registration errors (TRE) of 1.8 mm ± 0.9 mm was achieved. For co-registration between 2D X-ray images and 3D models from MRI images, a TRE of 2.3 ± 0.9 mm was achieved. Conclusion: A novel and fully automatic detection framework and its clinical applications are developed. Significance: The proposed framework can be applied to improve the accuracy of image-guidance systems for cardiac catheterization procedures. [ABSTRACT FROM AUTHOR]

This paper considers the Holzapfel–Ogden (HO) model to examine the behavior of the left ventricle myocardium. At the tissue level, we analyze the contributions of the orientation angle of muscle fibers (MFs) and investigate their effects on the occurrence of certain cardiomyopathies and congenital diseases at the organ level. Knowing the importance of myocardial microstructure on cardiac function, we vary the angle between the direction of collagen sheets and MFs in all layers of the myocardium (from epicardium to endocardium) to model the effects of tilted MFs. Based on the HO model in which the directions of the fibers are orthogonal and using the strain energy of HO, we construct a tensile-compression test and simulate the dynamics of a cubic sample. We recover the authors' results exhibiting the existence of residual stresses in various directions. Then, we modify the energy of HO slightly to assess the impact of the same stress states on the system with tilted MFs. A numerical tensile-compression test performed on this new cubic sample shows that, in certain directions, the heart tissue is more resistant to shear deformations in some planes than in others. Moreover, it appears that the residual stress is smaller as the angle of orientation of the MFs is small. Furthermore, we observe that the residual stress is greater in the new model compared to the normal HO model. This could affect the heart muscle at the organ level leading to hypertrophied/dilated cardiomyopathy. [ABSTRACT FROM AUTHOR]

This paper investigates the possible effects of patient recumbency positions on one of the parameters used in clinical chest electrical impedance tomography (EIT) monitoring -- the silent spaces. This parameter impacts medical decisions and interventions as it indicates how well each lung is being ventilated. Yet, it can be significantly affected by the assumed prior model including the alternations amid internal displacement and deformations caused by movement of heart, mediastinum and diaphragm based on their weight and abdominal cavity pressure when switching recumbency positions. To evaluate the effect of prior model adjustment in accordance to patient position, an 18-month old infant who was radiographed in supine and both decubitus lateral postures was used as a guide to create 3D compatible models and calculate corresponding silent spaces. These values were then compared with prior and post model updates according to recumbency positions for the patient. The results show average improvements of 7 and 15% in left and right lung silent spaces respectively when the updated models were applied. [ABSTRACT FROM AUTHOR]

This paper discusses the close similarities between Husserl's, Scheler's and Stein's concept of the person as an absolute value that exercises itself in position-takings. Ethics, for the classical phenomenologists, Husserl, Scheler, and Stein, concerns the whole person, including the affective and rational dimensions, intellect and the heart, as well as volition. Persons are distinctive for their free agency, capacity to recognize norms, and ability to interact responsibly with other personal agents in the context of the communal and historical life-world. [ABSTRACT FROM AUTHOR]

This paper intends to discuss the relationship between media competence and fan culture, focusing on content creation shared on Twitter by fans of the Limantha ship, from the Brazilian telenovela Young Hearts (Malhação: Viva a Diferença). In order to reflect on how telenovela social issues were explored in the content shared on Twitter, we adopted Ferrés and Piscitelli’s concept of media competence. We concluded that, in addition to deepening themes dealt within the plot, fans expanded and resignified discussions based on correlations with personal reports. [ABSTRACT FROM AUTHOR]

The image of the heart regularly appears in our daily lives: it decorates multiple everyday objects, such as clothing, logos, shop windows, and it appears on graffiti. Additionally, it is ubiquitous in the digital world, as the "like" button is often in the shape of a heart. The aim of this paper is to identify the reasons why the image of the heart is so widespread, and the functions performed by its representation. In order to do so, we carried out a linguistic and semiotic landscape study, by analysing a large corpus of images of hearts, collected in the urban landscape and on the Internet. The results show that the hearts found in the two corpora perform all language functions identified by Jakobson (1984); the main contexts of use of the heart are the expression of love, appreciation, and gratitude. Finally, we comment on the "transfer" of functions of the heart from street to screen and vice versa. [ABSTRACT FROM AUTHOR]

Within the scope of this technical report, the feasibility of indocyanine green (ICG) as a fluorescent agent for postmortem angiography of the heart is tested. The study included 4 deceased persons with no respective medical history of heart diseases. The basic patterns of findings in ICG fluorescence angiography associated with healthy hearts are presented. The method can easily be integrated into a workflow without restricting the macroscopic or histologic diagnostics. This paper represents the fundamental technical and analytical basis for upcoming studies concerning the possibilities and limitations of fluorescence angiography in the diagnosis of heart pathology. [ABSTRACT FROM AUTHOR]

During the past 30 years, rate of coronary artery disease (CAD), as the main cause of sudden death (SD), has decreased more than rate of SD. Likewise, cause of SD remains elusive in not a trivial portion of its victims. One possible reason is attention to only one organ, the heart, as the cause of SD. In fact, SD literature focuses more on the heart, less on the brain, and seldom on both. A change is required. In this paper, we first review the pathological findings seen in heart autopsies of SD victims after psychological stressors such as physical assault victims without internal injuries. Then, we summarize new studies investigating brain areas, like the insula, whose malfunctions and injuries are related to SD. Next, we review prototypes of neurological diseases and psychological stressors associated with SD and look at heart failure (HF)-related SD providing evidence for the brainheart connection. Finally, we propose a new look at SD risk factors considering both brain and heart in their association with SD, and review strategies for prevention of SD from this perspective. [ABSTRACT FROM AUTHOR]

This paper compares a newspaper article written by Gabrielle Roy, «Pitié pour les institutrices!» (1942), and her book of short stories, Ces enfants de ma vie (Children of my Heart), published in 1977. The subject in both of these is the schoolteacher and Roy draws upon her own experience teaching in Manitoba schools. The status of women is also an important theme in both. As well, the portrait of Mlle Estelle in the newspaper article appears to be a pre-text for the story of Clair, «L’enfant de Noël», in Children of my Heart. Despite some differences, the continuity of Gabrielle Roy’s literary inspiration is obvious, as is the importance of her own life and work. [ABSTRACT FROM AUTHOR]

Objective. The present paper aims to investigate the role of computed tomography as an imaging technique of diagnosis in the identification of the os cordis in ovine, and also how this anatomical structure is morphotopographically characterized in macro and microscopic contexts, seeking to contribute for its functional understanding. Materials and method. The heart of a young male ovine had been donated to the Laboratory of Animal Anatomy of the Surgery Department of the FMVZ/USP, first being subject to a post-mortem examination by means of the cardiac "shedding" (transverse cross sectioning of the heart). A tomographic examination of the anatomic specimen was carried out, as well as the dissection and histological analysis of the collected sample. Results. The results indicate the presence of an osseous structure of 6.39 mm in length, located in the aortic valve of the heart, next to a ring comprised by three valve flaps, tendinous cords, and papillary muscles. The histological findings consist of fibrous connective tissue, cancellous bone tissue, and calcified hyaline cartilage wherein the cardiomyocytes are attached. Conclusions. It is concluded that computed tomography, even though seldom applied to animals of zootechnical interest, poses as an effective tool for the visualization of the os cordis in lambs. [ABSTRACT FROM AUTHOR]

This paper proposes a semi-automatic Fontan surgery planning method for designing and manufacturing hemodynamically optimized patient-specific grafts. Fontan surgery is a palliative procedure for patients with a single ventricle heart defect by creating a new path using a vascular graft for the deoxygenated blood to be directed to the lungs, bypassing the heart. However, designing patient-specific grafts with optimized hemodynamic performance is a complex task due to the variety of patient-specific anatomies, confined surgical planning space, and the requirement of simultaneously considering multiple design criteria for vascular graft optimization. To address these challenges, we used parameterized Fontan pathways to explore patient-specific vascular graft design spaces and search for optimal solutions by formulating a nonlinear constrained optimization problem, which minimizes indexed power loss (iPL) of the Fontan model by constraining hepatic flow distribution (HFD), percentage of abnormal wall shear stress (%WSS) and geometric interference between Fontan pathways and the heart models (InDep) within clinically acceptable thresholds. Gaussian process regression was employed to build surrogate models of the hemodynamic parameters as well as InDep and $\text{N}_\text{v}$ (conduit model smoothness indicator) for optimization by pattern search. We tested the proposed method on two patient-specific models (n=2). The results showed the automatically optimized (AutoOpt) Fontan models hemodynamically outperformed or at least are comparable to manually optimized Fontan models with significantly reduced surgical planning time (15 hours versus over 2 weeks). We also demonstrated feasibility of manufacturing the AutoOpt Fontan conduits by using electrospun nanofibers. [ABSTRACT FROM AUTHOR]

Quantitative assessment of myocardial stiffness is crucial to understand and evaluate cardiac biomechanics and function. Despite the recent progresses of ultrasonic shear wave elastography, quantitative evaluation of myocardial stiffness still remains a challenge because of strong elastic anisotropy. In this paper we introduce a smart ultrasound approach for non-invasive real-time quantification of shear wave velocity (SWV) and elastic fractional anisotropy (FA) in locally transverse isotropic elastic medium such as the myocardium. The approach relies on a simultaneous multidirectional evaluation of the SWV without a prior knowledge of the fiber orientation. We demonstrated that it can quantify accurately SWV in the range of 1.5 to 6 m/s in transverse isotropic medium (FA < 0.7) using numerical simulations. Experimental validation was performed on calibrated phantoms and anisotropic ex vivo tissues. A mean absolute error of 0.22 m/s was found when compared to gold standard measurements. Finally, in vivo feasibility of myocardial anisotropic stiffness assessment was evaluated in four healthy volunteers on the antero-septo basal segment and on anterior free wall of the right ventricle (RV) in end-diastole. A mean longitudinal SWV of 1.08 ± 0.20 m/s was measured on the RV wall and 1.74 ± 0.51 m/s on the septal wall with a good intra-volunteer reproducibility (±0.18 m/s). This approach has the potential to become a clinical tool for the quantitative evaluation of myocardial stiffness and diastolic function. [ABSTRACT FROM AUTHOR]

The emergence of deep learning has considerably advanced the state-of-the-art in cardiac magnetic resonance (CMR) segmentation. Many techniques have been proposed over the last few years, bringing the accuracy of automated segmentation close to human performance. However, these models have been all too often trained and validated using cardiac imaging samples from single clinical centres or homogeneous imaging protocols. This has prevented the development and validation of models that are generalizable across different clinical centres, imaging conditions or scanner vendors. To promote further research and scientific benchmarking in the field of generalizable deep learning for cardiac segmentation, this paper presents the results of the Multi-Centre, Multi-Vendor and Multi-Disease Cardiac Segmentation (M&Ms) Challenge, which was recently organized as part of the MICCAI 2020 Conference. A total of 14 teams submitted different solutions to the problem, combining various baseline models, data augmentation strategies, and domain adaptation techniques. The obtained results indicate the importance of intensity-driven data augmentation, as well as the need for further research to improve generalizability towards unseen scanner vendors or new imaging protocols. Furthermore, we present a new resource of 375 heterogeneous CMR datasets acquired by using four different scanner vendors in six hospitals and three different countries (Spain, Canada and Germany), which we provide as open-access for the community to enable future research in the field. [ABSTRACT FROM AUTHOR]

Background: Rare diseases are chronic and life-threatening disorders affecting < 1 person every 2,000. For most of them, clinical symptoms and signs can be observed at birth or childhood. Approximately 80% of all rare diseases have a genetic background and most of them are monogenic conditions. In addition, while the majority of these diseases is still incurable, early diagnosis and specific treatment can improve patients' quality of life. Transplantation is among the therapeutic options and represents the definitive treatment for end-stage organ failure, both in children and adults. The aim of this paper was to analyze, in a large cohort of Italian patients, the main rare genetic diseases that led to organ transplantation, specifically pointing the attention on the pediatric cohort. Results: To the purpose of our analysis, we considered heart, lung, liver and kidney transplants included in the Transplant Registry (TR) of the Italian National Transplantation Center in the 2002–2019 timeframe. Overall, 49,404 recipients were enrolled in the cohort, 5.1% of whom in the pediatric age. For 40,909 (82.8%) transplant recipients, a disease diagnosis was available, of which 38,615 in the adult cohort, while 8,495 patients (17.2%) were undiagnosed. There were 128 disease categories, and of these, 117 were listed in the main rare disease databases. In the pediatric cohort, 2,294 (5.6%) patients had a disease diagnosis: of the 2,126 (92.7%) patients affected by a rare disease, 1,402 (61.1%) presented with a monogenic condition. As expected, the frequencies of pathologies leading to organ failure were different between the pediatric and the adult cohort. Moreover, the pediatric group was characterized, compared to the adult one, by an overall better survival of the graft at ten years after transplant, with the only exception of lung transplants. When comparing survival considering rare vs non-rare diseases or rare and monogenic vs rare non-monogenic conditions, no differences were highlighted for kidney and lung transplants, while rare diseases had a better survival in liver as opposed to heart transplants. Conclusions: This work represents the first national survey analyzing the main genetic causes and frequencies of rare and/or monogenic diseases leading to organ failure and requiring transplantation both in adults and children. [ABSTRACT FROM AUTHOR]

Dilated cardiomyopathy (DCM) is a cardiomyopathy with left ventricle or double ventricle enlargement and systolic dysfunction. It is an important cause of sudden cardiac death and heart failure and is the leading indication for cardiac transplantation. Major heart diseases like heart muscle damage and valvular problems are diagnosed using cardiac MRI. However, it takes time for cardiologists to measure DCM-related parameters to decide whether patients have this disease. We have presented a method for automatic ventricular segmentation, parameter extraction, and diagnosing DCM. In this paper, left ventricle and right ventricle are segmented by parasternal short-axis cardiac MR image sequence; then, related parameters are extracted in the end-diastole and end-systole of the heart. Machine learning classifiers use extracted parameters as input to predict normal people and patients with DCM, among which Random forest classifier gives the highest accuracy. The results show that the proposed system can be effectively utilized to detect and diagnose DCM automatically. The experimental results suggest the capabilities and advantages of the proposed method to diagnose DCM. A small amount of sample input can generate results comparable to more complex methods. [ABSTRACT FROM AUTHOR]

Sleep appears to have been of no interest to sociocultural linguistics or communication studies. This is in spite of growing attention to the "ignored third" from sociologists and anthropologists, especially in response to rising public, medical and commercial concerns. Having said which, these cognate fields side-step the classist representational politics of sleep which are exposed nicely by a social semiotic intervention like the one reported here. In this regard, the empirical basis of my paper is an archive of promotional materials from some thirty international airlines touting their latest "premium" sleeping services, a key component of current marketing strategies. Through a largely visual, iconographic analysis, I examine the staging of sleep as a sensuous experience and as a deeply affective, intimate encounter between (often male) passengers and (often female) flight attendants. Sleep emerges as a semiotic resource for producing, circulating and normalizing relations of entitlement – a symbolic economy which exceeds and/or intensifies established forms of emotional labour. These highly seductive ways of organizing and envisioning sleep generate the kind of desire necessary for subjugating an otherwise privileged few, and, thus, for exploiting many others. [ABSTRACT FROM AUTHOR]

The Production Assistance for Cellular Therapies (PACT) Program, is funded and supported by the US Department of Health and Human Services' National Institutes of Health (NIH) National Heart Lung and Blood Institute (NHLBI) to advance development of somatic cell and genetically modified cell therapeutics in the areas of heart, lung, and blood diseases. The program began in 2003, continued under two competitive renewals, and ended June 2021. PACT has supported cell therapy product manufacturing, investigational new drug enabling preclinical studies, and translational services, and has provided regulatory assistance for candidate cell therapy products that may aid in the repair and regeneration of damaged/diseased cells, tissues, and organs. PACT currently supports the development of novel cell therapies through five cell processing facilities. These facilities offer manufacturing processes, analytical development, technology transfer, process scale‐up, and preclinical development expertise necessary to produce cell therapy products that are compliant with Good Laboratory Practices, current Good Manufacturing Practices, and current Good Tissue Practices regulations. The Emmes Company, LLC, serves as the Coordinating Center and assists with the management and coordination of PACT and its application submission and review process. This paper discusses the impact and accomplishments of the PACT program on the cell therapy field and its evolution over the duration of the program. It highlights the work that has been accomplished and provides a foundation to build future programs with similar goals to advance cellular therapeutics in a coordinated and centralized programmatic manner to support unmet medical needs within NHLBI purview. [ABSTRACT FROM AUTHOR]

Medical images do not provide a natural visualization of 3D anatomical structures, while 3D digital models are able to solve this problem. Interesting applications based on these models can be found in the cardiovascular field. The generation of a good-quality anatomical model of the heart is one of the most complex tasks in this context. Its 3D representation has the potential to provide detailed spatial information concerning the heart's structure, also offering the opportunity for further investigations if combined with additive manufacturing. When investigated, the adaption of printed models turned out to be beneficial in complex surgical procedure planning, for training, education and medical communication. In this paper, we will illustrate the difficulties that may be encountered in the workflow from a stack of Computed Tomography (CT) to the hand-held printed heart model. An important goal will consist in the realization of a heart model that can take into account real wall thickness variability. Stereolithography printing technology will be exploited with a commercial rigid resin. A flexible material will be tested too, but results will not be so satisfactory. As a preliminary validation of this kind of approach, print accuracy will be evaluated by directly comparing 3D scanner acquisitions to the original Standard Tessellation Language (STL) files. [ABSTRACT FROM AUTHOR]

Automatic and accurate 3D cardiac image segmentation plays a crucial role in cardiac disease diagnosis and treatment. Even though CNN based techniques have achieved great success in medical image segmentation, the expensive annotation, large memory consumption, and insufficient generalization ability still pose challenges to their application in clinical practice, especially in the case of 3D segmentation from high-resolution and large-dimension volumetric imaging. In this paper, we propose a few-shot learning framework by combining ideas of semi-supervised learning and self-training for whole heart segmentation and achieve promising accuracy with a Dice score of 0.890 and a Hausdorff distance of 18.539 mm with only four labeled data for training. When more labeled data provided, the model can generalize better across institutions. The key to success lies in the selection and evolution of high-quality pseudo labels in cascaded learning. A shape-constrained network is built to assess the quality of pseudo labels, and the self-training stages with alternative global-local perspectives are employed to improve the pseudo labels. We evaluate our method on the CTA dataset of the MM-WHS 2017 Challenge and a larger multi-center dataset. In the experiments, our method outperforms the state-of-the-art methods significantly and has great generalization ability on the unseen data. We also demonstrate, by a study of two 4D (3D+T) CTA data, the potential of our method to be applied in clinical practice. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has driven an upheaval of new research, providing key insights into the pathogenesis of this disease. Lymphocytopenia, hyper-inflammation and cardiac involvement are prominent features of the disease and have prognostic value. However, the mechanistic links among these phenomena are not well understood. Likewise, some COVID-19 patients exhibit multi-organ failure with diseases affecting the cardiac system, appearing to be an emerging feature of the COVID-19 pandemic. Neutrophil extracellular traps (NETs) have been frequently correlated with larger infarct sizes and can predict major adverse cardiac events. However, the exact mechanism behind this remains unknown. Although the excessive NET formation can drive inflammation, particularly endothelial and promote thrombosis, it is essential to normal immunity. In this paper, we postulate the role of NETs in cardiac disease by providing an overview of the relationship between NET and inflammasome activities in lung and liver diseases, speculating a link between these entities in cardiac diseases as well. Future research is required to specify the role of NETs in COVID-19, since this carries potential therapeutic significance, as inhibition of NETosis could alleviate symptoms of this disease. Knowledge gained from this could serve to inform the assessment and therapeutics of other hyper inflammatory diseases affecting the heart and vasculature alike. [ABSTRACT FROM AUTHOR]

This article discusses the "heart" as part of the terminology for selfhood in ancient Jewish literature. After discussing a couple of criticisms of studies of the self and showing how these criticisms fail to persuade, the paper examines a range of texts in the Hebrew Bible, the Dead Sea Scrolls, and beyond for conceptions of the moral self. Special attention is given to the legal S tradition in the Scrolls as a fruitful illustration of how the self and law are recurring conceptual companions. In this legal tradition, a universalizing conception of selfhood and agency is rooted in local, practical concerns of a community. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to study the effects of Pu’er tea extract and Kuding tea extract on the heart and skeletal muscle of bullfrog and the mechanism of action. [Method] The gastrocnemius muscle of bullfrog was soaked in two tea extracts, and the systolic indexes were recorded.The effects of two tea extracts on the content of acetylcholine（Ach） and the activity of acetylcholinesterase（A-CHE） at the junction of sciatic nerve-gastrocnemius were determined.Two tea extracts of different concentrations were used to irrigate the heart of bullfrog, and the contraction changes were recorded.CaCl2, Ach and high concentration tea extract were selected to co-incubate to observe the effects of frog heart contraction. [Result] The results showed that both tea extracts could promote the contraction and relaxation of skeletal muscle, and the mechanisms were related to the increase of Ca2+ concentration in sarcoplasm by promoting Ca2+ from terminal cisterna into sarcoplasm and the increase of the Ach content by inhibiting the activity of A-CHE at the junction. Two tea extracts all could inhibit the contraction of isolated frog heart, and both could cooperate with the inhibitory effect of Ach on the contraction of isolated frog heart, and inhibit the promoting effect of CaCl2. The mechanisms of action may be related to blocking the ICa-L and activating the M receptors of myocardium membrane, reducing the intracellular cAMP concentration and inhibiting the extracellular Ca2+ influx. [Conclusion] The effects of Pu’er tea on skeletal muscle and myocardium were more obvious than those of Kuding tea. [ABSTRACT FROM AUTHOR]

Background: Rare diseases are chronic and life-threatening disorders affecting < 1 person every 2,000. For most of them, clinical symptoms and signs can be observed at birth or childhood. Approximately 80% of all rare diseases have a genetic background and most of them are monogenic conditions. In addition, while the majority of these diseases is still incurable, early diagnosis and specific treatment can improve patients' quality of life. Transplantation is among the therapeutic options and represents the definitive treatment for end-stage organ failure, both in children and adults. The aim of this paper was to analyze, in a large cohort of Italian patients, the main rare genetic diseases that led to organ transplantation, specifically pointing the attention on the pediatric cohort.Results: To the purpose of our analysis, we considered heart, lung, liver and kidney transplants included in the Transplant Registry (TR) of the Italian National Transplantation Center in the 2002-2019 timeframe. Overall, 49,404 recipients were enrolled in the cohort, 5.1% of whom in the pediatric age. For 40,909 (82.8%) transplant recipients, a disease diagnosis was available, of which 38,615 in the adult cohort, while 8,495 patients (17.2%) were undiagnosed. There were 128 disease categories, and of these, 117 were listed in the main rare disease databases. In the pediatric cohort, 2,294 (5.6%) patients had a disease diagnosis: of the 2,126 (92.7%) patients affected by a rare disease, 1,402 (61.1%) presented with a monogenic condition. As expected, the frequencies of pathologies leading to organ failure were different between the pediatric and the adult cohort. Moreover, the pediatric group was characterized, compared to the adult one, by an overall better survival of the graft at ten years after transplant, with the only exception of lung transplants. When comparing survival considering rare vs non-rare diseases or rare and monogenic vs rare non-monogenic conditions, no differences were highlighted for kidney and lung transplants, while rare diseases had a better survival in liver as opposed to heart transplants.Conclusions: This work represents the first national survey analyzing the main genetic causes and frequencies of rare and/or monogenic diseases leading to organ failure and requiring transplantation both in adults and children. [ABSTRACT FROM AUTHOR]

The Human Organ Transplantation Act came into officially force in Bangladesh on April 13, 1999, allowing organ donations from both living and brain-dead donors. The Act was amended by the Parliament on January 8, 2018, with the changes coming into effect shortly afterwards on January 28. The Act was revised to extend a living donor pool from close relatives (e.g., parents, adult sons and daughters, adult brothers and sisters, uncles and aunts from both the paternal and maternal sides, and spouses) to include certain other relatives such as grandparents, grandchildren, and first cousins (Section 2:4). The Act was also revised to allow individuals to prioritize family members in receiving their organs after their death (Section 7c:3). The aim of this paper is not to carry out an ethical analysis of the Act as a whole but only to focus on aspects relating to priority access for family members to organs. Despite Islam encouraging Muslims to be sympathetic, and to save the life of any member of humankind (Quran 5:32), saving the life of a relative through organ donation is even more highly valued. The collective and extended structure of the family impacts on the provisions of the Act that only allows Bangladeshis to legally donate their organs to save the lives of relatives and allows individuals to prioritize family members. Recent progress in the practice of organ transplantation raises a number of ethical dilemmas around the allocation of available organs in the context of organ scarcity. A key purpose of introducing incentive into the system of organ allocation is to increase the number of donations from living relatives and initiation of vital organ donations from brain-dead donors. However, allocation criteria based on a living organ donation incentive system would appear to be unethical because there is no provision in the Act with regard to financial compensation for a distant relative donor's post-operative care in the absence of healthcare coverage. Receiving organs from a distant relative without giving financial compensation for post-operative care places them in a grave health condition and violates the biomedical principle of non-maleficence. An incentive system around brain-dead donors would appear to be ethical as the amended Act allows individuals to prioritize relatives in receiving their organs after death. This provision is intended to initiate the transplantation of vital organs (e.g., kidney, liver, heart, pancreas, bone marrow) from brain-dead donors as families might bear the cost of keeping the organs alive for transplantation. Regular reassessment of the impact of the Act is necessary to maximize the donation rate of transplantable organs using ethical means. [ABSTRACT FROM AUTHOR]

In this paper, we propose a parallel source separation system designed to extract heart and lung sounds from single-channel mixtures. The proposed system is based on a non-negative matrix factorization (NMF) approach and a clustering strategy together with a soft-masking filtering. Furthermore, we propose an offline and online implementation of the framework which can be applied in many real-time scenarios, such as the extraction of clinical parameters, remote auscultation and breath sound analysis. Experimental results show that it is possible to achieve fast execution times, which enable a real-time behavior, combining parallel and high-performance techniques. [ABSTRACT FROM AUTHOR]

Cancer pain is one of the main botherings of cancer patients in the late stage・ Although the u three - stepcancer pain treatment principle in western medicine has obvious effects on most patients, there are still defects such as great toxic and side effects・ In TCM, cancer pain is classified as a "pain pattern・ According to the 19 pathogenesis explored in Huang Di Nei Jing (The Yellow EmperorJ s Inner Classic): Basic Questions, u all pain, itchiness or sore disorders pertain to the heart, and modern studies have gradually found that cancer pain is related to the fonction of the "heart"・ Therefore, based on the theory of "all pain, itchiness or sore disorders pertaining to the heart", this paper sorts out its related historical origin and modem extension, analyzes the relationship between the function of the heart and cancer pain, summarizes the corresponding treatment principles and methods, and improves the principle-method・fornitda・medicine system for the treatment of cancer pain from the perspective of the heart, thus attempting to open up a new way for the treatment of cancer pain. [ABSTRACT FROM AUTHOR]

Development of new drugs is of high interest for the field of cardiac and cardiovascular diseases, which are a dominant cause of death worldwide. Before being allowed to be used and distributed, every new potentially therapeutic compound must be strictly validated during preclinical and clinical trials. The preclinical studies usually involve the in vitro and in vivo evaluation. Due to the increasing reporting of discrepancy in drug effects in animal and humans and the requirement to reduce the number of animals used in research, improvement of in vitro models based on human cells is indispensable. Primary cardiac cells are difficult to access and maintain in cell culture for extensive experiments; therefore, the human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) became an excellent alternative. This technology enables a production of high number of patient- and disease-specific cardiomyocytes and other cardiac cell types for a large-scale research. The drug effects can be extensively evaluated in the context of electrophysiological responses with a use of well-established tools, such as multielectrode array (MEA), patch clamp, or calcium ion oscillation measurements. Cardiotoxicity, which is a common reason for withdrawing drugs from marketing or rejection at final stages of clinical trials, can be easily verified with a use of hiPSC-CM model providing a prediction of human-specific responses and higher safety of clinical trials involving patient cohort. Abovementioned studies can be performed using two-dimensional cell culture providing a high-throughput and relatively lower costs. On the other hand, more complex structures, such as engineered heart tissue, organoids, or spheroids, frequently applied as co-culture systems, represent more physiological conditions and higher maturation rate of hiPSC-derived cells. Furthermore, heart-on-a-chip technology has recently become an increasingly popular tool, as it implements controllable culture conditions, application of various stimulations and continuous parameters read-out. This paper is an overview of possible use of cardiomyocytes and other cardiac cell types derived from hiPSC as in vitro models of heart in drug research area prepared on the basis of latest scientific reports and providing thorough discussion regarding their advantages and limitations. [ABSTRACT FROM AUTHOR]

In this paper, we study the propagation of the cardiac action potential in a one-dimensional fiber, where cells are electrically coupled through gap junctions (GJs). We consider gap junctional gate dynamics that depend on the intercellular potential. We find that different GJs in the tissue can end up in two different states: a low conducting state and a high conducting state. We first present evidence of the dynamical multistability that occurs by setting specific parameters of the GJ dynamics. Subsequently, we explain how the multistability is a direct consequence of the GJ stability problem by reducing the dynamical system's dimensions. The conductance dispersion usually occurs on a large time scale, i.e., thousands of heartbeats. The full cardiac model simulations are computationally demanding, and we derive a simplified model that allows for a reduction in the computational cost of four orders of magnitude. This simplified model reproduces nearly quantitatively the results provided by the original full model. We explain the discrepancies between the two models due to the simplified model's lack of spatial correlations. This simplified model provides a valuable tool to explore cardiac dynamics over very long time scales. That is highly relevant in studying diseases that develop on a large time scale compared to the basic heartbeat. As in the brain, plasticity and tissue remodeling are crucial parameters in determining the action potential wave propagation's stability. [ABSTRACT FROM AUTHOR]

Heart Mountain, Wyoming, USA, is a geological puzzle. "Paleozoic" carbonates overlie "much younger Mesozoic and Cenozoic" rock. The implication is that several mountain-sized blocks broke from a detachment fault and slid up to 45 km. Part 1 of this series critiqued recent models that propose low-friction cushions to move the Heart Mountain blocks. This paper compliments that study by examining how the proposed movement started and was sustained over uneven terrain via seven questions raised by uniformitarian researchers. Current models, uniformitarian and creationist, cannot explain the location of Heart Mountain as a detachment and slide. Unless fresh ideas are forthcoming, the implication that these "Paleozoic" rocks of Heart Mountain are younger, not older, than the underlying "Mesozoic" rocks needs exploring. [ABSTRACT FROM AUTHOR]

This paper proposes a new technique for the identification of fundamental heart sounds (HSs), namely, $S_{1}$ and $S_{2}$ from the cardiac cycle, the first and foremost step in the automated HSs analysis for the detection of pathological events, without incorporating time-interval informations between $S_{1}$ and $S_{2}$ or electrocardiogram signal as reference. The motive of this paper is to demonstrate that the reliable $S_{1}$ and $S_{2}$ classification performances based on the combinatory feature (CF) derived from higher order moments and cepstral-based domain can still be achieved, under the circumstances where the timing interval information might not be easily understood due to cardiac abnormalities. Using deep neural networks approach, a stacked autoencoder (SAE) based on the CF is proposed for the classification of fundamental HSs. Experiments are conducted on both publicly available and recorded HSs signals for the validation of the proposed method. The SAE using the proposed CF achieves better classification results in recognizing $S_{1}$ and $S_{2}$ in comparison to well-known classifiers such as deep belief neural network, support vector machine, Naive Bayes, linear discriminant analysis, and boosting ensemble. The proposed method shows higher classification rate in terms of accuracy, sensitivity, and specificity by considering CF, which uses Mel-frequency cepstral coefficients and its derivative features. A second approach for addressing the problem of $S_{1}$ and $S_{2}$ identifications is carried out by employing 1-D convolutional neural network that uses the signals directly to learn the relevant features by its own for the recognition. [ABSTRACT FROM AUTHOR]

Ultrafast acoustoelectric imaging (UAI) is a novel method for the mapping of biological current densities, which may improve the diagnosis and monitoring of cardiac activation diseases such as arrhythmias. This paper evaluates the feasibility of performing UAI in beating rat hearts. A previously described system based on a 256-channel ultrasound research platform fitted with a 5-MHz linear array was used for simultaneous UAI, ultrafast B-mode, and electrocardiogram (ECG) recordings. In this paper, rat hearts (n = 4) were retroperfused within a Langendorff isolated heart system. A pair of Ag/Cl electrodes were positioned on the epicardium to simultaneously record ECG and UAI signals for imaging frame rates of up to 1000 Hz and a mechanical index of 1.3. To account for the potential effect of motion on the UAI maps, acquisitions for n = 3 hearts were performed with and without suppression of the mechanical contraction using 2,3-butanedione monoxime. Current densities were detected for all four rats in the region of the atrio-ventricular node, with an average contrast-to-noise ratios of 12. The UAI signals’ frequency matched the sinus rhythm, even without mechanical contraction, suggesting that the signals measured correspond to physiological electrical activation. UAI signals appeared at the apex and within the ventricular walls with a delay estimated at 29 ms. Finally, the signals from different electrode positions along the myocardium wall showed the possibility of mapping the electrical activation throughout the heart. These results show the potential of UAI for cardiac activation mapping in vivo and in real time. [ABSTRACT FROM AUTHOR]

This paper formulates a support vector machine with quantile hyper-spheres (QHSVM) for pattern classification. The idea of QHSVM is to build two quantile hyper-spheres with the same center for positive or negative training samples. Every quantile hyper-sphere is constructed by using pinball loss instead of hinge loss, which makes the new classification model be insensitive to noise, especially the feature noise around the decision boundary. Moreover, the robustness and generalization of QHSVM are strengthened through maximizing the margin between two quantile hyper-spheres, maximizing the inner-class clustering of samples and optimizing the independent quadratic programming for a target class. Besides that, this paper proposes a novel local center-based density estimation method. Based on it, ρ-QHSVM with surrounding and clustering samples is given. Under the premise of high accuracy, the execution speed of ρ-QHSVM can be adjusted. The experimental results in artificial, benchmark and strip steel surface defects datasets show that the QHSVM model has distinct advantages in accuracy and the ρ-QHSVM model is fit for large-scale datasets. [ABSTRACT FROM AUTHOR]

Today's implantable mechanical circulatory support devices, such as left ventricular assist devices, still rely on a percutaneous driveline, which is a frequent cause of severe infections and which reduces the quality of life for the patients. Inductive power transfer (IPT) is therefore a promising technology to replace the driveline and, hence, reducing the likelihood of an infection. This paper focuses on the series–series compensated IPT system and provides an in-depth comparison of two operating modes, i.e., the operation at resonance and the operation above resonance, and highlights the advantages and disadvantages with respect to the requirements set by the application at hand. In addition, the paper presents the design and the realization of a fully functional transcutaneous energy transfer (TET) implant hardware prototype, which includes the IPT front-end, the control circuit, the backup battery and its charging converter, as well as the communication electronics in a boxed volume of only 10.3 cl. The experimental verification shows that overall dc–dc efficiencies of up to 90% can be achieved for both operating modes when transmitting 25–30 W from the external battery to the implant backup battery, each having a nominal voltage of 14.8 V, using TET coils with 70 mm diameter and 10 mm coil separation distance. [ABSTRACT FROM AUTHOR]

Delineation of the left ventricular cavity, myocardium, and right ventricle from cardiac magnetic resonance images (multi-slice 2-D cine MRI) is a common clinical task to establish diagnosis. The automation of the corresponding tasks has thus been the subject of intense research over the past decades. In this paper, we introduce the “Automatic Cardiac Diagnosis Challenge” dataset (ACDC), the largest publicly available and fully annotated dataset for the purpose of cardiac MRI (CMR) assessment. The dataset contains data from 150 multi-equipments CMRI recordings with reference measurements and classification from two medical experts. The overarching objective of this paper is to measure how far state-of-the-art deep learning methods can go at assessing CMRI, i.e., segmenting the myocardium and the two ventricles as well as classifying pathologies. In the wake of the 2017 MICCAI-ACDC challenge, we report results from deep learning methods provided by nine research groups for the segmentation task and four groups for the classification task. Results show that the best methods faithfully reproduce the expert analysis, leading to a mean value of 0.97 correlation score for the automatic extraction of clinical indices and an accuracy of 0.96 for automatic diagnosis. These results clearly open the door to highly accurate and fully automatic analysis of cardiac CMRI. We also identify scenarios for which deep learning methods are still failing. Both the dataset and detailed results are publicly available online, while the platform will remain open for new submissions. [ABSTRACT FROM AUTHOR]

• Risk analysis for cargo tank cracking on oil/chemical tanker ship. • The Bow tie method for performing risk analysis is adopted under the Dempster–Shafer (D-S) evidence theory – Human Error Assessment and Reduction Technique (HEART). • Enhancing safety awareness about the risk of cargo tank cracking on oil/chemical tanker ships. Oil/chemical tanker ships are designed to transport liquefied chemicals in a series of discrete cargo tanks. Even a minor crack in the cargo tanks can have catastrophic consequences financially, and for the marine environment and human life. For oil/chemical tanker shipping operations, risk analysis is of great importance to improve safety and minimise risk at the operational level during the transportation of chemical cargo. This paper focuses on the risk of cargo tank cracking on oil/chemical tanker ships. The robust bow-tie risk analysis method is adopted under the Dempster–Shafer (D-S) evidence theory – Human Error Assessment and Reduction Technique (HEART) approach. In Bow-tie, which analyses the possible causes and consequences of failures, the top event is determined as the risk of cargo tank cracking on an oil/chemical tanker. The probabilities of basic events are calculated with D-S evidence-based HEART, where expert opinions are combined. Besides the theoretical contribution, the outputs of the paper provide practical contributions to oil/chemical tanker owners and operators, safety researchers, safety inspectors, and superintendents by providing the information needed to minimise the risk associated with cargo tank cracks in oil/chemical tankers. [ABSTRACT FROM AUTHOR]

The endogenous and dietary agent, alpha lipoic acid (ALA), is evaluated for its capacity to induce a broad spectrum of adaptive responses via hormetic dose responses and their underlying mechanisms. ALA was shown to induce hormetic effects in a wide range of experimental models within in vitro and in vivo experimental settings which included direct exposure and pre- and post-conditioning experimental protocols. The hormetic effects occur in a broad range of organ systems, including the brain, heart, kidney and other tissues, with possible public health and clinical/therapeutic applications linked to reducing the onset and progression of neurogenerative diseases and also in the preservation of sperm health and functionality during cryopreservation. This paper provides the first integrated assessment of ALA-induced hormetic dose responses. Underlying mechanisms that mediated the occurrence of ALA-induced hormetic effects involved the induction of low levels of ROS that activate key cell signaling antioxidant (e.g. Nrf2) pathways. [Display omitted] • First paper assessing capacity of ALA to induce hormetic dose responses. • ALA was shown to induce hormetic effects in a wide range of experimental models. • Experiments included direct exposure and pre- and post-conditioning protocols. • ALA induced protective effects via hormesis in a broad range of tissues/cell types. • Mechanisms involving low levels of ROS activate key cell signaling pathways. [ABSTRACT FROM AUTHOR]

Unlike many spiritual authors of his time or earlier times, Ignatius of Loyola prefers to use the term "enemy" or, even, the expression "enemy of human nature", when speaking of the devil. We investigate such expressions in this paper: we analyse their occurrence in Ignatian writings and explore the sources from which Ignatius may have drawn. The difficulty in tracing their origins leads us to investigate separately the meaning of "enemy" and "human nature" in Ignatius' semantic/cultural horizon, and then to combine these terms and formulate some hypotheses about the meaning Ignatius gave to the expressions under investigation. What emerges is a vision of an eschatological combat taking place in the heart of every man and woman, in which what is at stake is precisely the interpretation of human nature and the full accomplishment of man in God. [ABSTRACT FROM AUTHOR]

This paper studies Guardini's perception of Augustine, especially in his two widely unknown books on Confessions: Die Bekehrung des heiligen Aurelius Augustinus (1935), and Anfang (1944), which are contrasted by the recently published Guardini lectures: Ewigkeit und Geschichte (1955/56 and 1961/62). The author discusses Guardini's emphasis and fascination with Augustine's conversion (cf. Conf. VIII), as it was relevant for his existential theology. Additionally, the text explores the Augustinian perception of the phenomenon of conversion by studying the passage from In evangelium Ioannis tractatus 53 (John 12:40), where Augustine delivers a beautiful synthesis about the conversion of the heart through grace: "Conversio gratia est" (Aug., In Io. tr. 53.11). It is hoped this study will evaluate Guardini's doctrine about the conversion of the heart using the concrete example of Augustine and also replenish and enrich his interpretation by contrasting it to the broader Augustinian corpus. [ABSTRACT FROM AUTHOR]

Heart Mountain, Wyoming, USA, is a geological puzzle. Paleozoic carbonates overlie much younger Lower Cenozoic rock. So, either several mountain-sized blocks broke apart and slid up to 45 km from where they were originally deposited onto the younger rock or the way the relative ages of the base layer and the blocks are assessed is wrong. This paper, with its partner, examines the issues and problems explaining this proposed event. Part 1 examines three (uniformitarian) models of a low-angle slide on a low-friction cushion. In Part 2, another six essential issues, including how the movement started and was sustained over uneven terrain, are examined. The joint conclusion is that present models are seriously inadequate. [ABSTRACT FROM AUTHOR]

Automatic and accurate segmentation of the whole heart structure from 3D cardiac images plays an important role in helping physicians diagnose and treat cardiovascular disease. However, the time-consuming and laborious manual labeling of the heart images results in the inefficiency of utilizing the existing CT or MRI for training the deep learning network, which decrease the accuracy of whole heart segmentation. However, multi-modality data contains multi-level information of cardiac images due to different imaging mechanisms, which is beneficial to improve the segmentation accuracy. Therefore, this paper proposes a cascaded framework with cross-modality transfer learning for whole heart segmentation (CM-TranCaF), which consists of three key modules: modality transfer network (MTN), U-shaped multi-attention network (MAUNet) and spatial configuration network (SCN). In MTN, MRI images are transferred from MRI domain to CT domain, to increase the data volume by adopting the idea of adversarial training. The MAUNet is designed based on UNet, while the attention gates (AGs) are integrated into the skip connection to reduce the weight of background pixels. Moreover, to solve the problem of boundary blur, the position attention block (PAB) is also integrated into the bottom layer to aggregate similar features. Finally, the SCN is used to finetune the segmentation results by utilizing the anatomical information between different cardiac substructures. By evaluating the proposed method on the dataset of the MM-WHS challenge, CM-TranCaF achieves a Dice score of 91.1% on the testing dataset. The extensive experimental results prove the effectiveness of the proposed method compared to other state-of-the-art methods. [Display omitted] • The CM-TranCaF framework improves heart segmentation, transferring MRI to CT while preserving heart shape using the MTN module. MAUNet addresses class imbalances and boundary clarity, and SCN module uses spatial relations to boost segmentation accuracy. Achieving a 91.1% Dice score and a 14.386 mm Hausdorff Distance on the MM-WHS dataset, our method demonstrates competitive performance against other techniques. [ABSTRACT FROM AUTHOR]

In this paper we present a compact version of the Heart iteration. One that computes low-rank approximations of large sparse matrices. The new iteration is a restarted Krylov method that is based on explicit restarts and Gram–Schmidt orthogonalizations. It is a simple algorithm that requires a minimal amount of computer storage as well as a minimal number of matrix–vector products per iteration. Yet it enjoys a fast rate of convergence. Numerical experiments illustrate the usefulness of the proposed approach. [ABSTRACT FROM AUTHOR]

• Gas bubbles in a non-Newtonian fluid under the influence of an external acoustic. • It transforms the generalized RP-equation for viscoelastic fluids. • A wide range of physical parameter values to address convergence issues. • Response Surface Methodology (RSM) is employed to investigate. • Rheological fluid on the pressure threshold required for inertial cavitation. Ultrasound imaging, or sonography, utilizes high-frequency sound waves to create images of the internal structures of the human body. It is widely applied in medical diagnostics due to its non-invasive nature and real-time capabilities. Ultrasound waves are emitted into the body, and their reflections are captured to generate detailed images of organs, tissues, fetuses during pregnancy, and more. The interaction between sound waves and biological tissues and issues related to propagation, reflection, and absorption of ultrasound are crucial considerations for improving image quality and safety. It is frequently used to keep an eye on the health and development of the fetus throughout pregnancy. The examination of several organs, including the heart, liver, kidneys, and blood arteries, is also done to look for anomalies, tumors, and other diseases. The dynamics of spherical gas bubbles within a non-Newtonian fluid exposed to an external sonic field are examined in this paper. The mathematical model offers a useful foundation for examining bubble behavior since it incorporates the additional stress tensor of a tangent hyperbolic fluid. The generalized RP problem may be transformed into an ordinary differential equation that can be solved using numerical methods, allowing a large range of parameter values to be investigated and resolving convergence difficulties. Particularly noteworthy are the numerical results for long acoustic cycles. The link between input and output variables is also investigated using an experimental methodology closely related to sensitivity analysis, which is important for possible device development. This innovative approach offers a fresh perspective on the subject. [ABSTRACT FROM AUTHOR]

We introduce Branched Latent Neural Maps (BLNMs) to learn finite dimensional input–output maps encoding complex physical processes. A BLNM is defined by a simple and compact feedforward partially-connected neural network that structurally disentangles inputs with different intrinsic roles, such as the time variable from model parameters of a differential equation, while transferring them into a generic field of interest. BLNMs leverage latent outputs to enhance the learned dynamics and break the curse of dimensionality by showing excellent in-distribution generalization properties with small training datasets and short training times on a single processor. Indeed, their in-distribution generalization error remains comparable regardless of the adopted discretization during the testing phase. Moreover, the partial connections, in place of a fully-connected structure, significantly reduce the number of tunable parameters. We show the capabilities of BLNMs in a challenging test case involving biophysically detailed electrophysiology simulations in a biventricular cardiac model of a pediatric patient with hypoplastic left heart syndrome. The model includes a 1D Purkinje network for fast conduction and a 3D heart-torso geometry. Specifically, we trained BLNMs on 150 in silico generated 12-lead electrocardiograms (ECGs) while spanning 7 model parameters, covering cell-scale, organ-level and electrical dyssynchrony. Although the 12-lead ECGs manifest very fast dynamics with sharp gradients, after automatic hyperparameter tuning the optimal BLNM, trained in less than 3 h on a single CPU, retains just 7 hidden layers and 19 neurons per layer. The resulting mean square error is on the order of 1 0 − 4 on an independent test dataset comprised of 50 additional electrophysiology simulations. In the online phase, the BLNM allows for 5000x faster real-time simulations of cardiac electrophysiology on a single core standard computer and can be employed to solve inverse problems via global optimization in a few seconds of computational time. This paper provides a novel computational tool to build reliable and efficient reduced-order models for digital twinning in engineering applications. The Julia implementation is publicly available under MIT License at https://github.com/StanfordCBCL/BLNM.jl. [ABSTRACT FROM AUTHOR]