Mechanical and microstructural properties of fiber-reinforced basalt rock cutting waste-based geopolymer composites exposed to high temperatures.

Managing basalt rock cutting waste in an environmentally responsible manner is crucial to mitigate its negative impacts and protect both the environment and human health. Recycling basalt rock cutting waste in geopolymer applications offers multiple environmental, economic, and performance benefits, making it a promising approach for sustainable construction practices. For this purpose, this study concerns about the performance of fiber-reinforced basalt rock-cutting waste-based geopolymer composites at high temperatures up to 1000 °C.

Flashbulb memories in the context of group hierarchies: effects of gender, system justification, and social dominance orientation on negative private and public flashbulb memories.

Research on flashbulb memories (FBMs) has primarily focused on cognitive aspects. However, recent studies indicate that FBMs are closely associated with social and cultural dynamics. This descriptive study explored the structural aspects and psychosocial functions of negative FBMs within the context of intergroup theories, mainly focusing on negative public (coup attempt in Türkiye on July 15, 2016) and private (bad news of a loved one) FBMs.

Analytical Computation of the Contact Force Jacobian for MRI-Actuated Robotic Catheter.

Contact force Jacobian relates the changes in the contact force to the changes in the actuation of a robotic catheter in contact with a surface. In this paper, we present an analytical method for calculating the contact force Jacobian for the Cosserat rod model of an MRI-actuated robotic catheter. First, the Cosserat rod model of the MRI-actuated robotic catheter under tip contact position constraint is introduced.

Application of portable sleep monitoring devices in pregnancy: a comprehensive review.

The physiological, hormonal and biomechanical changes during pregnancy may trigger sleep disordered breathing (SDB) in pregnant women. Pregnancy-related sleep disorders may associate with adverse fetal and maternal outcomes including gestational diabetes, preeclampsia, preterm birth and gestational hypertension. Most of the screening and diagnostic studies that explore SDB during pregnancy were based on questionnaires which are inherently limited in providing definitive conclusions.

Deformable cardiac surface tracking by adaptive estimation algorithms.

This study presents a particle filter based framework to track cardiac surface from a time sequence of single magnetic resonance imaging (MRI) slices with the future goal of utilizing the presented framework for interventional cardiovascular magnetic resonance procedures, which rely on the accurate and online tracking of the cardiac surface from MRI data. The framework exploits a low-order parametric deformable model of the cardiac surface. A stochastic dynamic system represents the cardiac surface motion.

Homology-Class Guided Rapidly-Exploring Random Tree For Belief Space Planning.

In this work, an efficient homology guided belief space planning method for obstacle-cluttered environments is presented. The proposed planner follows a two-step approach. First, a guided rapidly-exploring random tree (HRRT) algorithm is proposed to provide nominal trajectories in different homology classes by constructing homology aware sub-trees in a parallel manner.

State of the Art and Future Opportunities in MRI-Guided Robot-Assisted Surgery and Interventions.

Magnetic resonance imaging (MRI) can provide high-quality 3-D visualization of target anatomy, surrounding tissue, and instrumentation, but there are significant challenges in harnessing it for effectively guiding interventional procedures. Challenges include the strong static magnetic field, rapidly switching magnetic field gradients, high-power radio frequency pulses, sensitivity to electrical noise, and constrained space to operate within the bore of the scanner. MRI has a number of advantages over other medical imaging modalities, including no ionizing radiation, excellent soft-tissue contrast that allows for visualization of tumors and other features that are not readily visible by other modalities, true 3-D imaging capabilities, including the ability to image arbitrary scan plane geometry or perform volumetric imaging, and capability for multimodality sensing, including diffusion, dynamic contrast, blood flow, blood oxygenation, temperature, and tracking of biomarkers.

Quantitative Na-MRI of the intervertebral disk at 3 T.

Monitoring the tissue sodium content (TSC) in the intervertebral disk geometry noninvasively by MRI is a sensitive measure to estimate changes in the proteoglycan content of the intervertebral disk, which is a biomarker of degenerative disk disease (DDD) and of lumbar back pain (LBP). However, application of quantitative sodium concentration measurements in Na-MRI is highly challenging due to the lower in vivo concentrations and smaller gyromagnetic ratio, ultimately yielding much smaller signal relative to H-MRI. Moreover, imaging the intervertebral disk geometry imposes higher demands, mainly because the necessary RF volume coils produce highly inhomogeneous transmit field patterns.

MRI Distortion Correction and Robot-to-MRI Scanner Registration for an MRI-Guided Robotic System.

Magnetic resonance imaging (MRI) guided robotic procedures require safe robotic instrument navigation and precise target localization. This depends on reliable tracking of the instrument from MR images, which requires accurate registration of the robot to the scanner. A novel differential image based robot-to-MRI scanner registration approach is proposed that utilizes a set of active fiducial coils, where background subtraction method is employed for coil detection.

" Restaurant customer satisfaction during the COVID-19 outbreak: An analysis of Yelp review texts and star-ratings.

The aim of the study was to provide practical advice to restaurant managers for improving star ratings as well as information for researchers on how the pandemic has impacted established determinants of satisfaction. The study examined criteria used by restaurant customers in assigning star-ratings on Yelp during the COVID-19 pandemic using keyword analysis and Multiple Correspondence Analysis. In evaluating restaurants, the reviewers focused on service, overall experience, and food quality.

A Probabilistic Approach for Contact Stability and Contact Safety Analysis of Robotic Intracardiac Catheter.

The disturbances caused by the blood flow and tissue surface motions are major concerns during the motion planning of an intracardiac robotic catheter. Maintaining a stable and safe contact on the desired ablation point is essential for achieving effective lesions during the ablation procedure. In this paper, a probabilistic formulation of the contact stability and the contact safety for intravascular cardiac catheters under the blood flow and surface motion disturbances is presented.

Differential Image Based Robot to MRI Scanner Registration with Active Fiducial Markers for an MRI-Guided Robotic Catheter System.

In magnetic resonance imaging (MRI) guided robotic catheter ablation procedures, reliable tracking of the catheter within the MRI scanner is needed to safely navigate the catheter. This requires accurate registration of the catheter to the scanner. This paper presents a differential, multi-slice image-based registration approach utilizing active fiducial coils.

Contact Stability Analysis of Magnetically-Actuated Robotic Catheter Under Surface Motion.

Contact force quality is one of the most critical factors for safe and effective lesion formation during cardiac ablation. The contact force and contact stability plays important roles in determining the lesion size and creating a gap-free lesion. In this paper, the contact stability of a novel magnetic resonance imaging (MRI)-actuated robotic catheter under tissue surface motion is studied.

Analysis of Contact Stability and Contact Safety of a Robotic Intravascular Cardiac Catheter under Blood Flow Disturbances.

This paper studies the contact stability and contact safety of a robotic intravascular cardiac catheter under blood flow disturbances while in contact with tissue surface. A probabilistic blood flow disturbance model, where the blood flow drag forces on the catheter body are approximated using a quasi-static model, is introduced. Using this blood flow disturbance model, probabilistic contact stability and contact safety metrics, employing a sample based representation of the blood flow velocity distribution, are proposed.

Contact Stability and Contact Safety of a Magnetic Resonance Imaging-Guided Robotic Catheter Under Heart Surface Motion.

Contact force quality is one of the most critical factors for safe and effective lesion formation during catheter based atrial fibrillation ablation procedures. In this paper, the contact stability and contact safety of a novel magnetic resonance imaging (MRI)-actuated robotic cardiac ablation catheter subject to surface motion disturbances are studied. First, a quasi-static contact force optimization algorithm, which calculates the actuation needed to achieve a desired contact force at an instantaneous tissue surface configuration is introduced.

Camera-Robot Calibration for the da Vinci® Robotic Surgery System.

The development of autonomous or semi-autonomous surgical robots stands to improve the performance of existing teleoperated equipment, but requires fine hand-eye calibration between the free-moving endoscopic camera and patient-side manipulator arms (PSMs). A novel method of solving this problem for the da Vinci® robotic surgical system and kinematically similar systems is presented. First, a series of image-processing and optical-tracking operations are performed to compute the coordinate transformation between the endoscopic camera view frame and an optical-tracking marker permanently affixed to the camera body.

Conventional and Diffusion-Weighted MR Imaging Findings of Parotid Gland Tumors.

Objective: To investigate diffusion-weighted magnetic resonance imaging (MRI) findings of parotid gland lesions in addition to conventional MRI findings and demographic data.

Methods: A retrospective evaluation was made of the demographic data, histopathologic data, preoperative conventional and diffusion-weighted MRI of 74 patients who underwent parotidectomy. The patients were categorized according to the histopathology (pleomorphic adenoma [PA], Warthin's Tumor [WT] and malignant Tumor [MT]).

Vision-Based Surgical Tool Pose Estimation for the da Vinci Robotic Surgical System.

This paper presents an approach to surgical tool tracking using stereo vision for the da Vinci Surgical Robotic System. The proposed method is based on robot kinematics, computer vision techniques and Bayesian state estimation. The proposed method employs a silhouette rendering algorithm to create virtual images of the surgical tool by generating the silhouette of the defined tool geometry under the da Vinci robot endoscopes.

State Estimation for MRI-Actuated Catheters via Catadioptric Stereo Camera.

An MRI-actuated catheter is a novel robotic catheter system that utilizes the MR scanner for both remote steering and catheter tracking. In order to develop the mathematical model and the planning algorithm of the catheter in parallel to the MR tracking system, an alternative catheter tracking method is needed. This paper presents a catheter tracking algorithm based on the particle filter and the catadioptric camera system.

Analysis of Dynamic Response of an MRI-Guided Magnetically-Actuated Steerable Catheter System.

This paper presents a free-space open-loop dynamic response analysis for an MRI-guided magnetically-actuated steerable intra-vascular catheter system. The catheter tip is embedded with a set of current carrying micro-coils. The catheter is directly actuated via the magnetic torques generated on these coils by the magnetic field of the magnetic resonance imaging (MRI) scanner.

Closed-loop cavitation control for focused ultrasound-mediated blood-brain barrier opening by long-circulating microbubbles.

Focused ultrasound (FUS) exposure in the presence of microbubbles (MBs) has been successfully used in the delivery of various sizes of therapeutic molecules across the blood-brain barrier (BBB). While acoustic pressure is correlated with the BBB opening size, real-time control of BBB opening to avoid vascular and neural damage is still a challenge. This arises mainly from the variability of FUS-MB interactions due to the variations of animal-specific metabolic environment and specific experimental setup.

Jacobian-Based Task-Space Motion Planning for MRI-Actuated Continuum Robots.

Robot-assisted medical interventions, such as robotic catheter ablation, often require the robot to perform tasks on a tissue surface. This paper presents a task-space motion planning method that generates actuation trajectories which steer the end- effector of the MRI-actuated robot along desired trajectories on the surface. The continuum robot is modeled using the pseudo-rigid-body model, where the continuum body of the robot is approximated by rigid links joined by flexible joints.