User's Field Research Articles

Acceptance and feasibility of an augmented reality-based navigation system with optical tracking for percutaneous procedures in interventional radiology - a simulation-based phantom study.

Augmented reality (AR) projects additional information into the user's field of view during interventions. The aim was to evaluate the acceptance and clinical feasibility of an AR system and to compare users with different levels of experience. A system was examined that projects a CT-generated 3D model of a phantom into the field of view using a HoloLens 2, whereby the tracked needle is displayed and navigated live. A projected ultrasound image is used for live control of the needle positioning. This should minimize radiation exposure and improve orientation.The acceptance and usability of the AR navigation system was evaluated by 10 physicians and medical students with different levels of experience by performing punctures with the system in a phantom. The required time was then compared and a questionnaire was completed to assess clinical acceptance and feasibility. For statistical analysis, frequencies for qualitative characteristics, location and dispersion measures for quantitative characteristics and Spearman rank correlations for correlations were calculated.9 out of 10 subjects hit all 5 target regions in the first attempt, taking an average of 29:39 minutes for all punctures. There was a significant correlation between previous experience in interventional radiology, years in the profession, and the time required. Overall, the time varied from an average of 43:00 min. for medical students to 15:00 min. for chief physicians. All test subjects showed high acceptance of the system and rated especially the potential clinical feasibility, the simplification of the puncture, and the image quality positively. However, the majority require further training for sufficient safety in use.The system offers distinct advantages for navigation and orientation, facilitates percutaneous interventions during training and enables professionally experienced physicians to achieve short intervention times. In addition, the system improves ergonomics during the procedure by making important information always directly available in the field of view and has the potential to reduce the radiation exposure of staff in particular by combining AR and sonography and thus shortening CT-fluoroscopy times. · AR navigation offers advantages for orientation during percutaneous radiological interventions.. · The subjects would like to use the AR system in everyday clinical practice on patients.. · AR improves ergonomics by making important information directly available in the field of view.. · The combination of AR and sonography can significantly reduce radiation exposure for staff.. · Rohmer K, Becker M, Georgiades M et al. Acceptance and feasibility of an augmented reality-based navigation system with optical tracking for percutaneous procedures in interventional radiology - a simulation-based phantom study. Fortschr Röntgenstr 2024; DOI 10.1055/a-2416-1080.

The Use of Augmented Reality as an Educational Tool in Minimally Invasive Transforaminal Lumbar Interbody Fusion.

One of the major challenges in training neurosurgical and orthopedic residents the technique for minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is the lack of visualization of surgical landmarks (pedicle, pars, lamina). This is due to the limited access to the bony spine through a tubular retractor, in addition to a smaller working corridor or patient-specific factors such as bony overgrowth, disk space collapse, and listhesis. These factors increase the possibility for surgical error and prolonged surgery time. With augmented reality (AR), relevant surgical anatomy can be projected directly into the user's field of view through the microscope. The purpose of this study was to assess the utility, accuracy, efficiency, and precision of AR-guided MIS-TLIF and to determine its impact in spine surgery training. At 2 centers, 12 neurosurgical residents performed a one-level MIS-TLIF on a high-fidelity lumbar spine simulation model with and without AR projection into the microscope. For the MIS-TLIF procedures with AR, surgical landmarks were highlighted in different colors on preoperative image data. These landmarks were visualized in the spinal navigation application on the navigation monitor and in the microscope to confirm the relevant anatomy. Postprocedural surveys (National Aeronautics and Space Administration Task Load Index) were given to the residents. Twelve residents were included in this trial. AR-guided procedures had a consistent impact on resident anatomical orientation and workload experience. Procedures performed without AR had a significantly higher mental demand (P = .003) than with AR. Residents reported to a significantly higher rate that it was harder work for them to accomplish their level of performance without AR (P = .019). AR can bring a meaningful value in MIS teaching and training to confirm relevant anatomy in situations where the surgeon will have less direct visual access. AR used in surgical simulation can also speed the learning curve.

Sorghum landraces perform better than a commonly used cultivar under terminal drought, especially on sandy soil

Landraces of sorghum [Sorghum bicolor (L.) Moench] have a high potential for drought adaptations to increasingly extreme climates. We investigated the performance of five sorghum genotypes (four landraces and one commonly grown elite line) under water-limited conditions. Plants were grown until maturity in field-like columns on soils of four textures (silty clay, sandy loam, loamy sand, sand), which were dried during flowering stage down to 30 % usable field capacity. Plant transpiration, physiological characteristics, and yield were measured. For most of the measured parameters, the interaction between genotypes and soils was statistically significant. Alongside the gradient in available water between soils, plants had the highest total transpiration, transpiration efficiency (TE), harvest index (HI), and nutrient uptake in silty clay, steadily reduced towards soils with higher sand content. Especially in sandy soil, all measured plant performance parameters were significantly reduced compared to the other soils. There was a significant negative relationship between later flowering time and HI. While the elite cultivar M35–1 showed the highest TE, it suffered from late flowering and yield loss on all soils, especially when growing on sandy soil. The landraces IS 29914 and IS 8348 had a stable HI irrespective of their lowest TE. The shorter the plant, the better it coped with water and nutrient limitation and high transpiration efficiency was not connected to water conservation. The study overall emphasizes the high potential of sorghum landraces to overcome more extreme droughts as imposed by climate change. It also underlines the importance and strong interaction effect of soil texture on plant performance and transpiration efficiency, which is crucial to be considered in crop production. This outlines that specifically regions with sandy soils, characterized by low water-holding capacities, need genotypes that efficiently utilize the limited available water and nutrient resources – a genetic potential hidden in many landraces.

Driving Assistance System with Obstacle Avoidance for Electric Wheelchairs.

A system has been developed to convert manual wheelchairs into electric wheelchairs, providing assistance to users through the implemented algorithm, which ensures safe driving and obstacle avoidance. While manual wheelchairs are typically controlled indoors based on user preferences, they do not guarantee safe driving in areas outside the user's field of vision. The proposed model utilizes the dynamic window approach specifically designed for wheelchair use, allowing for obstacle avoidance. This method evaluates potential movements within a defined velocity space to calculate the optimal path, providing seamless and safe driving assistance in real time. This innovative approach enhances user assistance and safety by integrating state-of-the-art algorithms developed using the dynamic window approach alongside advanced sensor technology. With the assistance of LiDAR sensors, the system perceives the wheelchair's surroundings, generating real-time speed values within the algorithm framework to ensure secure driving. The model's ability to adapt to indoor environments and its robust performance in real-world scenarios underscore its potential for widespread application. This study has undergone various tests, conclusively proving that the system aids users in avoidance obstacles and ensures safe driving. These tests demonstrate significant improvements in maneuverability and user safety, highlighting a noteworthy advancement in assistive technology for individuals with limited mobility.

Object Detection for the Visually Impaired

This paper presents the design and development of a mobile application, built using Flutter, that leverages object detection to enhance the lives of visually impaired individuals. The application addresses a crucial challenge faced by this community – the lack of real-time information about their surroundings. We propose a solution that utilizes pre-trained machine learning models, potentially through TensorFlow Lite for on-device processing, to identify objects within the user's field of view captured by the smartphone camera. The application goes beyond simple object recognition. Detected objects are translated into natural language descriptions through text-to-speech functionality, providing crucial auditory cues about the environment. This real-time information stream empowers users to navigate their surroundings with greater confidence and independence. Accessibility is a core principle of this project. The user interface will be designed with compatibility for screen readers, ensuring seamless interaction for users who rely on assistive technologies. Haptic feedback mechanisms will be incorporated to provide non-visual cues and enhance the user experience. The ultimate goal of this project is to create a user-friendly and informative application that empowers visually impaired people to gain greater independence in their daily lives. The application has the potential to improve spatial awareness, foster a sense of security, and promote overall inclusion within society

Fumos: Neural Compression and Progressive Refinement for Continuous Point Cloud Video Streaming.

Point cloud video (PCV) offers watching experiences in photorealistic 3D scenes with six-degree-of-freedom (6-DoF), enabling a variety of VR and AR applications. The user's Field of View (FoV) is more fickle with 6-DoF movement than 3-DoF movement in 360-degree video. PCV streaming is extremely bandwidth-intensive. However, current streaming systems require hundreds of Mbps bandwidth, exceeding the bandwidth capabilities of commodity devices. To save bandwidth, FoV-adaptive streaming predicts a user's FoV and only downloads point cloud data falling in the predicted FoV. But it is difficult to accurately predict the user's FoV even 2-3 seconds before playback due to 6-DoF. Misprediction of FoV or network bandwidth dips results in frequent stalls. To avoid rebuffering, existing systems would cause incomplete FoV and degraded experience, deteriorating the user's quality of experience (QoE). In this paper, we describe Fumos, a novel system that preserves interactive experience by avoiding playback stalls while maintaining high perceptual quality and high compression rate. We find a research gap in inter-frame redundant utilization and progressive mechaism. Fumos has three crucial designs, including (1) Neural compression framework with inter-frame coding, namely N-PCC, which achieves both bandwidth efficiency and high fidelity. (2) Progressive refinement streaming framework that enables continuous playback by incrementally upgrading a fetched portion to a higher quality (3) System-level adaptation that employs Lyapunov optimization to jointly optimize the long-term user QoE. Experimental results demonstrate that Fumos significantly outperforms Draco, achieving an average decoding rate acceleration of over 260×. Moreover, the proposed compression framework N-PCC attains remarkable BD-Rate gains, averaging 91.7% and 51.7% against the state-of-the-art point cloud compression methods G-PCC and V-PCC, respectively.

Comparing Different Registration and Visualization Methods for Navigated Common Femoral Arterial Access-A Phantom Model Study Using Mixed Reality.

Mixed reality (MxR) enables the projection of virtual three-dimensional objects into the user's field of view via a head-mounted display (HMD). This phantom model study investigated three different workflows for navigated common femoral arterial (CFA) access and compared it to a conventional sonography-guided technique as a control. A total of 160 punctures were performed by 10 operators (5 experts and 5 non-experts). A successful CFA puncture was defined as puncture at the mid-level of the femoral head with the needle tip at the central lumen line in a 0° coronary insertion angle and a 45° sagittal insertion angle. Positional errors were quantified using cone-beam computed tomography following each attempt. Mixed effect modeling revealed that the distance from the needle entry site to the mid-level of the femoral head is significantly shorter for navigated techniques than for the control group. This highlights that three-dimensional visualization could increase the safety of CFA access. However, the navigated workflows are infrastructurally complex with limited usability and are associated with relevant cost. While navigated techniques appear as a potentially beneficial adjunct for safe CFA access, future developments should aim to reduce workflow complexity, avoid optical tracking systems, and offer more pragmatic methods of registration and instrument tracking.

Usability Testing of Mobile Applications: A Methodological Framework

Less than five percent of all mobile applications have become successful throughout 2023. The success of a new mobile application depends on a variety of factors ranging from business understanding, customer value, and perceived quality of use. In this sense, the topic of usability testing of mobile applications is relevant from the point of view of user satisfaction and acceptance. However, the current knowledge seems to be fragmented, scattered across many papers and reports, and sometimes poorly documented. This paper attempts to fill this gap by investigating the current state of knowledge by reviewing the previous literature relevant to the research topic and developing a unified view. In particular, the methodological framework is outlined and discussed, including the discourse on settings for laboratory and field studies, data collection techniques, experimental designs for mobile usability testing, and a generic research framework. Therefore, the paper contributes to both the theory and practice of human–computer interaction by providing methodological foundations for usability testing of mobile applications, paving the way for further studies in this area. Moreover, the paper provides a better understanding of the related topics, in particular shedding light on methodological foundations, key concepts, challenges, and issues, equipping readers with a comprehensive knowledge base to navigate and contribute to the advancement of the field of mobile usability.

Professional Development to Improve Responsible Beverage Service Training: Formative Research Results and Protocol for a Randomized Controlled Trial.

Improved interventions are needed to reduce the rate of driving while intoxicated. Responsible beverage service (RBS) training has reduced service to intoxicated patrons in licensed premises in several studies. Its efficacy might be improved by increasing the proper application and continued use of RBS with a professional development program in the 3 to 5 years between the required RBS retraining. This study aims to develop and evaluate a professional development component for an RBS training that aims to improve the effectiveness of the web-based training alone. In a 2-phase project, we are creating a professional development component for alcohol servers after completing an RBS training. The first phase involved formative research on the feasibility, acceptability, and potential effectiveness of components. Semistructured interviews with owners and managers of licensed establishments and focus groups and a survey with alcohol servers in New Mexico and Washington State examined support for RBS and the need for ongoing professional development to support RBS. A prototype of a professional development component, WayToServe Plus, was produced for delivery in social media posts on advanced RBS skills, support from experienced servers, professionalism, and basic management training. The prototype was evaluated in a usability survey and a field pilot study with alcohol servers in California, New Mexico, and Washington State. The second phase of the project will include full production of the professional development component. It will be delivered in Facebook private groups over 12 months and evaluated with a sample of licensed premises (ie, bars and restaurants) in California, New Mexico, and Washington State (n=180) in a 2-group randomized field trial (WayToServe training only vs WayToServe training and WayToServe Plus). Licensed establishments will be assessed for refusal of sales to apparently intoxicated pseudopatrons at baseline and 12 months after the intervention commences. Although owners and managers (n=10) and alcohol servers (n=43) were favorable toward RBS, they endorsed the need for ongoing support for RBS for servers and identified topics of interest. A prototype with 50 posts was successfully created. Servers felt that it was highly usable and appropriate for themselves and the premises in the usability survey (n=20) and field pilot test (n=110), with 85% (17/20) and 78% (46/59), respectively, saying they would use it. Servers receiving the professional development component had higher self-efficacy (d=0.30) and response efficacy (d=0.38) for RBS compared with untreated controls. Owners, managers, and servers believed that an ongoing professional development component on RBS would benefit servers and licensed premises. Servers were interested in using such a program, a large majority engaged with the prototype, and servers receiving it improved on theoretic mediators of RBS. Thus, the professional development component may improve RBS training. ClinicalTrials.gov NCT05779774; http://tinyurl.com/4mw6d2vk. DERR1-10.2196/49680.

Integrated Quantitative Evaluation of Spatial Cognition and Motor Function with HoloLens Mixed Reality.

The steady increase in the aging population worldwide is expected to cause a shortage of doctors and therapists for older people. This demographic shift requires more efficient and automated systems for rehabilitation and physical ability evaluations. Rehabilitation using mixed reality (MR) technology has attracted much attention in recent years. MR displays virtual objects on a head-mounted see-through display that overlies the user's field of vision and allows users to manipulate them as if they exist in reality. However, tasks in previous studies applying MR to rehabilitation have been limited to tasks in which the virtual objects are static and do not interact dynamically with the surrounding environment. Therefore, in this study, we developed an application to evaluate cognitive and motor functions with the aim of realizing a rehabilitation system that is dynamic and has interaction with the surrounding environment using MR technology. The developed application enabled effective evaluation of the user's spatial cognitive ability, task skillfulness, motor function, and decision-making ability. The results indicate the usefulness and feasibility of MR technology to quantify motor function and spatial cognition both for static and dynamic tasks in rehabilitation.

ASTHMAXcel PRO patient satisfaction and usability field testing

Background: ASTHMAXcel PRO, an enhanced version of the ASTHMAXcel mobile application, has been developed to deliver comprehensive, guideline-based asthma education while also facilitating the collection of patient-reported outcomes (PROs) and enhancing user experience. Objective: To perform field testing and conduct formative and summative evaluation of the ASTHMAXcel PRO application to assess its impact on patient satisfaction, usability, and usage. Methods: Twenty-eight adult patients completed a baseline visit during which ASTHMAXcel PRO was introduced, health literacy was assessed, and demographic data were collected. They were instructed to use the app for 4 weeks. The Questionnaire for User Interface Satisfaction (QUIS) and the Unified Theory of Acceptance and Use of Technology (UTAUT) questionnaire were administered at baseline and 4 weeks to assess user satisfaction and technology acceptance, respectively. Semi-structured interviews were conducted to gather feedback regarding the application from patients. Results: The baseline total scores were high for both UTAUT and QUIS (mean (SD): 64.2 (10.1), 6.8 (2.2) respectively) indicating that user satisfaction and acceptance began at high levels. UTAUT total score, as well as all domain scores, improved significantly from baseline to 4 weeks (p < 0.02). QUIS total score along with several domain scores (screen, system capabilities, usability) also increased from baseline to 4-weeks (p = 0.03, 0.01, 0.03, 0.01, respectively). These improvements remained significant when adjusting for age, gender, education, and health literacy. Patients reported that the application was helpful, informative, and easy to understand and use. Conclusion: The significant increases in satisfaction and technology adoption observed among ASTHMAXcel PRO users demonstrate that the application is viable and has the potential to improve upon usability challenges faced by existing mobile health applications.

Head-Mounted Displays in Context-Aware Systems for Open Surgery: A State-of-the-Art Review.

Surgical context-aware systems (SCAS), which leverage real-time data and analysis from the operating room to inform surgical activities, can be enhanced through the integration of head-mounted displays (HMDs). Rather than user-agnostic data derived from conventional, and often static, external sensors, HMD-based SCAS relies on dynamic user-centric sensing of the surgical context. The analyzed context-aware information is then augmented directly into a user's field of view via augmented reality (AR) to directly improve their task and decision-making capability. This stateof-the-art review complements previous reviews by exploring the advancement of HMD-based SCAS, including their development and impact on enhancing situational awareness and surgical outcomes in the operating room. The survey demonstrates that this technology can mitigate risks associated with gaps in surgical expertise, increase procedural efficiency, and improve patient outcomes. We also highlight key limitations still to be addressed by the research community, including improving prediction accuracy, robustly handling data heterogeneity, and reducing system latency.

The effects of Augmented Reality on operator Situation Awareness and Head-Down Time

A lack of navigator's Situation Awareness (SA) is one of the leading causes of maritime accidents. Visually observing the area surrounding a vessel continues to be a critical aspect and best practice of safe navigation to establish and maintain SA. Augmented Reality (AR) allows the placement of information in a user's field of view, which can encourage navigators to spend more time looking up at their external environment whilst still having access to operational data. However, empirical evidence on the impact of AR on maritime operations is limited. This paper investigates the effects of AR on navigator SA & Head-Down Time (HDT) using a within-group quasi-experimental design. Seventeen licensed navigators and nautical students analysed twelve navigation scenarios: six non-AR (control) and six AR (experimental) scenarios using a maritime training simulator. SA was measured via SAGAT scores for each scenario and the SA-SWORD to compare preferences. Each scenario was video recorded and analysed for participant's total amount of HDT and head-down occurrences in each scenario. Results found that the addition of AR significantly reduced participant HDT (by a factor of 2.67) and head-down occurrences (by 62%) in comparison to navigation scenarios without AR. Furthermore, AR did not significantly improve mean SA. This study contributes to the limited empirical data on the effects of AR on operator performance, demonstrating the potential value of AR for improving SA and facilitating increased head-up time during maritime navigation, which in turn could improve safety at sea.

Requirements for Universally Accessible Upper-Body Exercise Equipment: The Case of People with Spinal Cord Injuries in Korea.

People with disabilities face considerable obstacles when exercising, which precludes them from the social and health benefits of physical activity. Especially for individuals with paraplegia with spinal cord injuries, it is necessary to maintain continuous participation in physical activity even after discharge, as it helps to maintain mobility and daily living activities through upper body strength. However, the participation rate of people with disabilities in physical activity in Korea is still low, mainly due to the lack of exercise equipment and facilities. The aim of this study is to identify aspects that can be improved for better accessibility to exercise equipment for individuals with paraplegia with spinal cord injuries and to reach a consensus on possible guidelines for accessible exercise equipment. This study reviews and evaluated the usability of four existing upper-body exercise equipment for individuals with paraplegia with spinal cord injuries. To assess usability, task performance scores and time were measured, and a survey was conducted on safety and satisfaction. Based on these results, areas for improvement were identified. Through literature review, usability results, and opinions from various stakeholders, eight requirements for universal accessibility were proposed. It is necessary to consider how wheelchair users access the exercise equipment. The access method to the exercise area (facility regulations, auxiliary equipment to be provided, etc.) and placement of exercise equipment should also be considered. Information such as explanations of the exercise equipment and how to use it should be located within the wheelchair user's field of vision. Considering the participation rate in sports for people with disabilities in Korea, it is necessary to explain the exact exercise equipment and exercise method. It is also necessary to consider how wheelchair users transfer from the wheelchair to the seat of the exercise equipment. Parts that require manipulation of each exercise equipment must be within the wheelchair user's range of motion. Various supports or assistive devices that provide body support according to each piece of equipment are needed. In addition to the wheelchair's own brake, it is necessary to provide a fixing device so that the wheelchair does not move during the exercise. For people with spinal cord injuries, the arm ergometer, aerobic exercise equipment, showed higher scores in performance, stability, and satisfaction compared to other exercise equipment. Among the strength exercise equipment, shoulder press had an effect on performance, seated lat pull-down had an effect on stability, and seated chest press had an effect on satisfaction. Therefore, when selecting exercise equipment, it is necessary to recommend aerobic and strength exercise equipment according to the preferences of people with spinal cord injuries. When developing strength exercise equipment, it is necessary to consider usability evaluation factors for individuals with spinal cord injury.

Invited Session IV: Extended reality--applications in vision science and beyond: Augmented reality systems for people with low vision.

Low vision is a visual impairment that falls short of blindness but cannot be corrected by eyeglasses or contact lenses. While current low vision aids (e.g., magnifier, CCTV) support basic vision enhancements, such as magnification and contrast enhancement, these enhancements often arbitrarily alter a user's full field of view without considering the user's context, such as their visual abilities, tasks, and environmental factors. As a result, these low vision aids are not sufficient or preferred by low vision users in many important tasks. Augmented reality (AR) technology presents a unique opportunity to enhance low vision people's visual experience by automatically recognizing the surrounding environment and presenting tailored visual augmentations. In this talk, I will talk about how we design and build intelligent AR systems to support low vision people in visual tasks, such as a head-mounted AR system that presents visual cues to orient users' attention in a visual search task, as well as a projection-based AR system that projects visual highlights on the stair edges to support safe stair navigation. I will conclude my talk by discussing our future research direction on AR for low vision accessibility.

Precious metal clusters as fundamental agents in bioimaging usability.

Fluorescent nanomaterials (NMs) are widely used in imaging techniques in biomedical research. Especially in bioimaging systems, with the rapid development of imaging nanotechnology, precious metal clusters such as Au, Ag, and Cu NMs have emerged with different functional agents for biomedical applications. Compared with traditional fluorescent molecules, precious metal clusters have the advantages of high optical stability, easy regulation of shape and size, and multifunctionalization. In addition, NMs possess strong photoluminescent properties with good photostability, high release rate, and sub-nanometer size. They could be treated as fundamental agents in bioimaging usability. This review summarizes the recent advances in bioimaging utilization, it conveys that metal clusters refer to Au, Ag, and Cu fluorescent clusters and could provide a generalized overview of their full applications. It includes optical property measurement, precious metal clusters in bioimaging systems, and a rare earth element-doped heterogeneous structure illustrated in biomedical imaging with specific examples, that provide new and innovative ideas for fluorescent NMs in the field of bioimaging usability.

Mitigation of VR Sickness During Locomotion With a Motion-Based Dynamic Vision Modulator.

In virtual reality, VR sickness resulting from continuous locomotion via controllers or joysticks is still a significant problem. In this article, we present a set of algorithms to mitigate VR sickness that dynamically modulate the user's field of view by modifying the contrast of the periphery based on movement, color, and depth. In contrast with previous work, this vision modulator is a shader that is triggered by specific motions known to cause VR sickness, such as acceleration, strafing, and linear velocity. Moreover, the algorithm is governed by delta velocity, delta angle, and average color of the view. We ran two experiments with different washout periods to investigate the effectiveness of dynamic modulation on the symptoms of VR sickness, in which we compared this approach against a baseline and pitch-black field-of-view restrictors. Our first experiment made use of a just-noticeable-sickness design, which can be useful for building experiments with a short washout period.

Augmented Reality in Neurosurgery: A New Paradigm for Training.

Augmented reality (AR) involves the overlay of computer-generated images onto the user's real-world visual field to modify or enhance the user's visual experience. With respect to neurosurgery, AR integrates preoperative and intraoperative imaging data to create an enriched surgical experience that has been shown to improve surgical planning, refine neuronavigation, and reduce operation time. In addition, AR has the potential to serve as a valuable training tool for neurosurgeons in a way that minimizes patient risk while facilitating comprehensive training opportunities. The increased use of AR in neurosurgery over the past decade has led to innovative research endeavors aiming to develop novel, more efficient AR systems while also improving and refining present ones. In this review, we provide a concise overview of AR, detail current and emerging uses of AR in neurosurgery and neurosurgical training, discuss the limitations of AR, and provide future research directions. Following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), 386 articles were initially identified. Two independent reviewers (GH and AC) assessed article eligibility for inclusion, and 31 articles are included in this review. The literature search included original (retrospective and prospective) articles and case reports published in English between 2013 and 2023. AR assistance has shown promise within neuro-oncology, spinal neurosurgery, neurovascular surgery, skull-base surgery, and pediatric neurosurgery. Intraoperative use of AR was found to primarily assist with surgical planning and neuronavigation. Similarly, AR assistance for neurosurgical training focused primarily on surgical planning and neuronavigation. However, studies included in this review utilize small sample sizes and remain largely in the preliminary phase. Thus, future research must be conducted to further refine AR systems before widespread intraoperative and educational use.

Analysis of mixed-mode Compact-Tension-Shear (CTS) specimens with slanted propagating cracks

Compact-Tension-Shear (CTS) specimen with its loading device has been widely used in mixed-mode I&II fatigue crack growth (FCG) experiments. To accurately describe the FCG behavior of materials, it is necessary to determine both the crack length and the parameters that represent crack driving force or crack front stress field in real-time. However, the relevant solutions are currently incomplete or insufficient. In this paper, for CTS specimen with slanted propagating crack, the variations of stress field parameters including stress intensity factors (SIFs) and T-stresses, as well as crack-mouth-opening-displacement (CMOD) compliance were investigated through finite element (FE) analysis. The results show that KI, KII and T11 are greatly influenced by the initial crack length ratio, the slanted propagating crack length ratio and the loading angle, but rarely by the specimen thickness among the considered range of geometries; T33 as an out-of-plane constraint parameter, however, is subject to the coupling effects of in-plane geometries, out-of-plane geometries and the mixed-mode loading. Moreover, it is shown that the measurement span has an effect on CMOD-compliance results for CTS specimens under mixed-mode loading, which is only negligible within the recommended range of D/W∈(0.02, 0.16]. Finally, the accuracy of the developed CMOD-compliance equations was validated through FCG experiments. The conclusions obtained in the current work will provide usable constraint-related crack front stress field parameter solutions for the analysis of FCG behavior in mixed fracture mode, and also give a reliable non-visual method for the determination of fatigue propagating crack length in CTS experiments.

Airy beam light sheet microscopy boosted by deep learning deconvolution.

Common light sheet microscopy comes with a trade-off between light sheet width defining the optical sectioning and the usable field of view arising from the divergence of the illuminating Gaussian beam. To overcome this, low-diverging Airy beams have been introduced. Airy beams, however, exhibit side lobes degrading image contrast. Here, we constructed an Airy beam light sheet microscope, and developed a deep learning image deconvolution to remove the effects of the side lobes without knowledge of the point spread function. Using a generative adversarial network and high-quality training data, we significantly enhanced image contrast and improved the performance of a bicubic upscaling. We evaluated the performance with fluorescently labeled neurons in mouse brain tissue samples. We found that deep learning-based deconvolution was about 20-fold faster than the standard approach. The combination of Airy beam light sheet microscopy and deep learning deconvolution allows imaging large volumes rapidly and with high quality.