The introduction of lung navigation systems in the clinical practice has enabled a transbronchial minimally invasive access to flexible microwave ablation catheters for the treatment of lung cancer lesions. These complex procedures are currently performed under Cone-Beam CT and require lung navigation system and bronchoscope. On bench lung models integrating tumor-mimicking targets for usability assessment are in demand due to the lack of representative in vivo models. In this paper, three tumor models made of minced bovine muscle, bovine tripe and ovine heart were integrated inside inflated ovine lungs and assessed in terms of radiopacity, required piercing force and dielectric properties. The impact of iodine to enhance radiopacity in the other desired model characteristics is also evaluated.
Evaluation of myocardial function is critical in severe inflammations as myocarditis, COVID-19 and sepsis, since it can lead to organ failure and death. Point-of-care detection of myocardial injury may improve the treatment of these critically ill patients. The study aimed to develop point of care technology for assessing the systolic and diastolic cardiac functions in animal model of systemic inflammation. Ultrasound and ventricular pressure were continuously recorded in Langendorff perfused isolated adult rat hearts. A computer controlled system controlled the ventricle loading conditions. The preload of both ventricles swung in a sinusoidal manner between target values of 2 and 22 mmHg. Collagenase (MMP8) was added to the Krebs-Henseleit solution following baseline recordings, to emulate the release of MMPs from activated leukocytes and macrophages. Collagenase perfusion led to gradual decline in peak systolic pressure and decrease in the end-diastolic volume (EDV), that were associated with concentric myocardial wall thickening. Extracellular matrix degradation by collagenases caused sever diastolic dysfunction with overt shift of the end-diastolic volume toward lower volumes, without significant changes in the epicardial diameter. Early detection of these signs may assist in assessing the severity of the myocardial injury and prompt the adequate treatment.
High precision indoor position estimation enables new opportunities for a variety of commercial, industrial and consumer applications. In this paper, we consider a phase-based method to calculate range from noisy measurements of a Frequency Comb in a multi-fading environment. It can be used to determine the range between devices for the next-generation High Accuracy Distance Measurement (HADM) protocol. We have conducted a quantitative analysis of various estimation approaches, considering both Monte-Carlo simulations of synthetic data in a variety of ranges. Moreover, we have proposed evaluation schemes for situations in which only a subset of data is available and some information may be missing, which extends existing approaches.
Cyber-Infrastructure (CI) is a critical element in achieving novel scientific discoveries and helping the research and development of new technologies. The next generation of research supporting CI should provide dynamic end-to-end platforms with guaranteed resource allocation and allow users to easily deploy the cyber-system elements and adapt them towards their current and future requirements. In this paper we consider a programmable cyber architecture which can implement this next generation of CI and discuss how the user requirements are met. This is based on a formal, comprehensive model for service abstraction and service construction – a framework and a generic virtualization model that offers a simplified common treatment of CI resources across all classes and services, in a scalable and secure architecture.
The increasing interest for high frequencies solicits the use of phaseless near-field-far-field (NF-FF) transformations for antenna characterization. The aim of this paper is to present a numerical validation of a phaseless NF-FF transformation with plane-polar scanning.A reduction of about 75% of the required NF samples as compared to standard λ/4 sampling is obtained by adopting an oblate spheroid to model the antenna under test (AUT) and by exploiting the non-redundant sampling representations of electromagnetic fields. An effective and proper representation of the unknowns, also taking advantage of the available information on the AUT, allows one to improve reliability and stability of the inversion process.Numerical results are presented.
