Augmented Reality

Augmented Reality (AR) is a natural development from virtual reality (VR), which was developed several decades earlier. AR complements VR in many ways. Due to the advantages of the user being able to see both the real and virtual objects simultaneously, AR is far more intuitive, but it's not completely detached from human factors and other restrictions. AR doesn't consume as much time and effort in the applications because it's not required to construct the entire virtual scene and the environment. In this book, several new and emerging application areas of AR are presented and divided into three sections. The first section contains applications in outdoor and mobile AR, such as construction, restoration, security and surveillance. The second section deals with AR in medical, biological, and human bodies. The third and final section contains a number of new and useful applications in daily living and learning

University of Windsor Graduate Calendar 1979-1980

https://scholar.uwindsor.ca/universitywindsorgraduatecalendars/1009/thumbnail.jp

1995-1996 Bulletin

Volume 106, Number 4. Scanned from the copy held in the Registrar\u27s Office.https://ecommons.udayton.edu/bulletin/1044/thumbnail.jp

1999 July, University of Memphis bulletin

Vol. 87, No. 4 of the University of Memphis bulletin containing the graduate catalog for 1999-2001.https://digitalcommons.memphis.edu/speccoll-ua-pub-bulletins/1187/thumbnail.jp

Exploring the Clinical Feasibility and Reliability of Three-Dimensional Echocardiography for Advanced Quantitative Analysis of Left Ventricular Myocardial Deformation

Background. Assessment of left ventricular (LV) function is a fundamental part of clinical cardiology, holding important diagnostic, prognostic and management implications. The most important advance in LV quantification over the last decade was the development of techniques aimed to quantify tissue motion and deformation from ultrasound images, such as tissue Doppler imaging (DTI) and two-dimensional speckle-tracking echocardiography (2DSTE). More recently, speckle-tracking algorithms have been applied to three-dimensional (3D) volumetric acquisitions of the LV (i.e. referred to as 3D speckle-tracking echocardiography, 3DSTE), making possible to analyze all LV myocardial strain components from the same dataset. At present, 3DSTE technology is a research tool in its infancy of development, and its potential clinical value still remains to be demonstrated. With respect to prior technologies (DTI and 2DSTE), 3DSTE comes with several advantages, but also with new challenges. It is currently unknown if the theoretical benefits of an additional third dimension to study the complex LV mechanics (no more “out-of-plane” motion of speckles, only a single acquisition needed etc) are not actually outweighted by the new technical challenges derived from using a volumetric acquisition of the LV (i.e. lower spatial and temporal resolution of speckles than with 2DSTE). A major concern of 2DSTE strain is the large intervendor variability of strain measurements provided by various commercially-available software packages. At present, it is unclear if a similar problem may affect also 3DSTE, and to what extent. Furthermore, despite researchers are increasingly employing 3DSTE to study various pathologic conditions, the reference values and normal pattern of LV myocardial strain in healthy adults by 3DSTE, as well as the possible influence of various clinical and technical factors on LV strain values are currently unknown. Finally, the validation process of 3DSTE is difficult due to the lack of adequate three-dimensional gold standard that can be applied noninvasively in human subjects to validate regional LV function in 3D. Therefore, there is a great need for rigorous validation work, methodological and intervendor standardization to be undertaken before its application in clinical settings. Methods and Results. Project design: single-centre, prospective, observational clinical study, aiming to explore the clinical feasibility and usefulness of LV 3D strain analysis using state-of-the-art commercially available 3DE equipment. The project involves a series of 4 clinical studies. The aim of the Study #1 was to assess the intervendor consistency and variability of LV 3D strain values between the two 3DSTE equipments commercially available: VividE9 (GE, Vingmed, Horten, Norway) and Artida (Toshiba Medical Systems Corporation, Tokyo, Japan) ultrasound systems. Sixty patients (38 ± 12 years, 64% males) with a wide range of LV end-diastolic volumes and ejection fractions were enrolled. Global longitudinal (3DLɛ), radial (3DRɛ), circumferential (3DCɛ) and area (3DAɛ) strain values were obtained offline using the corresponding proprietary software package. Overall, the intervendor agreement of 3DRɛ, 3DCɛ and 3DAɛ measured with Artida and VividE9 was poor. 3DLɛ showed the closest values between the two platforms (bias = 1.5%, limits of agreement (LOA) from −2.9 to −5.9%, P < 0.05). Artida provided significantly higher values of both 3DCɛ and 3DAɛ than VividE9 (bias = 6.6% for 3DCɛ, 6.0% for 3DAɛ and -24% for 3DRɛ respectively, P < 0.001). All 3D strain components showed good reproducibility (intraclass correlation coefficients: 0.82–0.98), except for 3DRɛ by Artida, which showed only a moderate reproducibility. Therefore, reference values should be identified for each system, and baseline and follow-up data in longitudinal studies should be obtained using the same 3DSTE equipment. The aim of the Study #2 was to assess the normative values for LV 3D strain in 218 healthy volunteers (age range 18-76, 57% women) by vendor-specific 3DSTE equipment (Vivid E9, 4D AutoLVQ software,). For comparison LV strain was also measured by vendor-specific 2DSTE software and by a vendor-independent 3DSTE software. Feasibility of global 3D strain analysis by 4D AutoLVQ was 89%, lower than 2DLε (95%) and similar to 2DCε (92%). Feasibility of segmental 3DSTE analysis ranged from 46% to 100%. Reference values of 3D strain parameters were identified according to gender and age group. 3DLε decreased, while 3DCε increased with ageing (p<0.001). Men had lower 3DLε, 3DRε, 3DAε and 2DLε than women (p<0.02). At stepwise multivariable linear regression analysis, demographic (age and gender), cardiac (LV size and mass) and technical (image quality and temporal resolution) factors accounted for the variance of LV 3D strain measurements. Since major inter-software differences in LV strain measurements were identified (p<0.001 for all), limits of normality for LV strain analysis by vendor-specific 3DSTE software should not be used interchangeably with those by 2DSTE or vendor-independent 3DSTE softwares. The aim of the Study #3 was to assess if LV deformation by 3D STE in patients after ST-elevation myocardial infarction (STEMI) could provide an accurate and objective assessment of infarct size and transmurality, in comparison with magnetic resonance with late gadolinium enhancement (LGE-CMR). A total of 77 STEMI patients were enrolled by 2D and 3D echo, and in 46 patients LGE-CMR studies were performed within 24 hours. The relative amount of DE tissue per segment was used to define transmural necrosis (51-100% DE). LV function was assessed from three apical LV 2D views by measuring 2DLε, and from 3D LV full-volume datasets, assessing visual wall motion score (WMS) and measuring 3DLε, 3DCε, 3DAε and 3DRε. Strain parameters were correlated with conventional indices of LV systolic function (LVEF) and infarct size (troponin I, WMSI, infarct size index at LGE-CMR). Despite a good accuracy for 2DLε and 3D strain parameters (AUC=0.81-0.73), visual wall motion assessment by experienced reader on good-quality 3D data sets (AUC=0.87) was found to be superior than strain quantification to predict transmural necrosis at LGE-CMR. The aims of the Study #4 to describe the LV myocardial mechanics in patients with hypertrophic cardiomyopathy (HCM) using 2DSTE and 3DSTE, and to compare it with the normal deformation pattern in healthy subjects. In 32 HCM pts and 32 age- and gender-matched controls, we analyzed peak global 2DLε and 3DLε, 3DCε, 3DRε, 3DAε. LV ejection fraction (LVEF), LV mass and outflow tract area (LVOTA) were measured by 3D echo. Symptomatic status was defined by NYHA class (II-IV). Although LVEF was similar in pts and controls (64±6% vs 62±4%, p=0.29), LV systolic strain was significantly impaired in pts (p<0.0001), except for 3DCε, which was only marginally lower. In HCM patients, all strain parameters were correlated with LV end-systolic volume (r=0.55 to 0.67), LVEF (r=-0.82 to -0.88) and mass (r=0.33 to 0.56). Symptomatic patients had more impaired 3DAε, 3DRε and 3DCε, but also had more LVOT obstruction and concentric remodelling, and higher E/e'. At ROC curve analysis, 3DAε, 3DRε and 3DCε had a good accuracy to identify symptomatic pts (AUCs 0.72-0.73). 3D LV mass had an inverse correlation with LV longitudinal deformation: r=-0.74 for 2DLε and -0.70 for 3DLε (p<0.001 for both). In HCM with preserved LVEF, the longitudinal strain was significantly reduced, however symptom development is multifactorial and related to the additional impairment of LV deformation in circumferential-radial direction. Conclusions. This project addressed several issues of of pivotal importance for 3DSTE. It provided a comprehensive analysis of 3DSTE measurement variability (intra- and inter-observer, at test-retest, inter-vendor and inter-software), and reported on the feasibility of 3DSTE in clinical setting and on the comparison with LV strain by 2DSTE. In addition, it is the first to report normal ranges of 3D strain parameters by 3DSTE using both vendor-specific and vendor-independent software packages. Finally, this project presents the added value of 3DSTE in comparison with previous methods for assessing LV function in 2 common pathologic conditions (acute STEMI, as the prototype of regional necrotic transmural injury; and HCM, as the prototype of myocardial disease with impaired longitudinal systolic mechanics despite preserved LVEF). This series of studies contributes with original data to the current scientific evidence-based knowledge on 3DSTE, which is essential for the development and appropriate use of this novel technology

Aeronautical engineering: A continuing bibliography with indexes (supplement 239)

This bibliography lists 454 reports, articles, and other documents introduced into the NASA scientific and technical information system in April, 1989. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

Analyzing Extracellular Vesicles as Potential Biomarkers of Stroke Using Polymer Microfluidic Devices

A major drawback of currently available stroke diagnosis methods, such as computed tomography (CT) and magnetic resonance (MRI), is that they cannot provide timely diagnosis within the narrow therapeutic time window of 4.5 h from stroke onset afforded by recombi-nant tissue plasminogen activator treatment. Upon initiation of a stroke event, CD15+ neu-trophils and CD8+ T cells are recruited and activated in response to the inflammatory stroke event and can release into blood extracellular vesicles (EVs) containing mRNA markers with altered expression profiles indicative of tissue damage. Our previous studies demonstrated that certain leukocyte subpopulations and gene expression profiling of these isolated sub-populations could be used to diagnose acute ischemic stroke (AIS) within 3 h. Here, our re-search goal was to develop a novel approach for the measurement of mRNA transcripts in EVs rather than cells as a possible diagnostic for AIS. To facilitate the development of the AIS diagnostic based on EVs, we developed a microfluidic device with a high-density array of antibody-modified micropillars for the affinity selection of CD8+ or CD15+ EVs with an analysis time less than the 4.5 h recombinant tissue plasminogen activator effective therapeu-tic time window. We successfully developed a microfluidic device with a high-density array of anti-body-modified micropillars for the affinity selection of CD8+ EVs, which could process 200 µL of plasma in 90%. Initial validation of these devices was per-formed using a model cell line Molt-3, which contained CD8+ T-cells. With the aid of fluo-rescence microscopy, we demonstrated that EVs can be affinity selected using the microflu-idic device with higher specificity compared to other EV isolation techniques, such as ul-trancentrifugation or PEG-precipitation that can improve the quality of the mRNA expression data. Transmission Electron Microscopy (TEM) and Nano Particle Tracking Analysis (NTA) revealed that the microfluidic device was capable of capturing and releasing enriched EVs with a short analysis time (<25 min). Gene expression analysis performed via droplet digital PCR revealed that for AIS, the genes we selected (PLBD1, MMP9, VCAN, FOS, CA4) pro-duce similar expression between the CD8+ T cells and EVs originating from these cells. The analysis of clinical samples, which used a 7-bed microfluidic device with 10 µm pillars and an interpillar spacing of 10 µm provided a higher dynamic range compared to a 3-bed device that used larger pillars (~90 µm) as well as significantly reduced processing time. In a blinded study performed for healthy and AIS patient samples, we were able to correctly identify 4/5 stroke patient samples and 4/5 healthy control samples. Although results reported here are very encouraging, more extensive studies are needed with a larger cohort of patient samples and healthy controls to clearly determine receiver operating characteristics for the use of EVs as a source of mRNA for AIS diagnosis. The research work I conducted on identification of mutations stabilizing Bacterioferritin associated ferredoxin is included in Appendix

Space Station Systems: a Bibliography with Indexes (Supplement 8)

This bibliography lists 950 reports, articles, and other documents introduced into the NASA scientific and technical information system between July 1, 1989 and December 31, 1989. Its purpose is to provide helpful information to researchers, designers and managers engaged in Space Station technology development and mission design. Coverage includes documents that define major systems and subsystems related to structures and dynamic control, electronics and power supplies, propulsion, and payload integration. In addition, orbital construction methods, servicing and support requirements, procedures and operations, and missions for the current and future Space Station are included