Fast KV-Switching and Dual-Layer Flat-Panel Detector Enabled Cone-Beam CT Joint Spectral Imaging

Purpose: Fast kV-switching (FKS) and dual-layer flat-panel detector (DL-FPD) technologies have been actively studied as promising dual-energy solutions for FPD-based cone-beam computed tomography (CBCT). However, CBCT spectral imaging is known to face challenges in obtaining accurate and robust material discrimination performance due to the limited energy separation. To further improve CBCT spectral imaging capability, this work aims to promote a source-detector joint spectral imaging solution which takes advantages of both FKS and DL-FPD, and to conduct a feasibility study on the first tabletop CBCT system with the joint spectral imaging capability developed. Methods: In this work, the first FKS and DL-FPD jointly enabled multi-energy tabletop CBCT system has been developed in our laboratory. To evaluate its spectral imaging performance, a set of physics experiments are conducted, where the multi-energy and head phantoms are scanned using the 80/105/130kVp switching pairs and projection data are collected using a prototype DL-FPD. To compensate for the slightly angular mismatch between the low- and high-energy projections in FKS, a dual-domain projection completion scheme is implemented. Afterwards material decomposition is carried out by using the maximum-likelihood method, followed by reconstruction of basis material and virtual monochromatic images. Results: The physics experiments confirmed the feasibility and superiority of the joint spectral imaging, whose CNR of the multi-energy phantom were boosted by an average improvement of 21.9%, 20.4% for water and 32.8%, 62.8% for iodine when compared with that of the FKS and DL-FPD in fan-beam and cone-beam experiments, respectively. Conclusions: A feasibility study of the joint spectral imaging for CBCT by utilizing both the FKS and DL-FPD was conducted, with the first tabletop CBCT system having such a capability being developed

Modification of the fatty acid composition in Arabidopsis and maize seeds using a stearoyl-acyl carrier protein desaturase-1 (ZmSAD1) gene

Composition of fatty acids in the transgenic ZmSAD1 Arabidopsis mature seeds (DOCX 17 kb

Generalized-Equiangular Geometry CT: Concept and Shift-Invariant FBP Algorithms

With advanced X-ray source and detector technologies being continuously developed, non-traditional CT geometries have been widely explored. Generalized-Equiangular Geometry CT (GEGCT) architecture, in which an X-ray source might be positioned radially far away from the focus of arced detector array that is equiangularly spaced, is of importance in many novel CT systems and designs. GEGCT, unfortunately, has no theoretically exact and shift-invariant analytical image reconstruction algorithm in general. In this study, to obtain fast and accurate reconstruction from GEGCT and to promote its system design and optimization, an in-depth investigation on a group of approximate Filtered BackProjection (FBP) algorithms with a variety of weighting strategies has been conducted. The architecture of GEGCT is first presented and characterized by using a normalized-radial-offset distance (NROD). Next, shift-invariant weighted FBP-type algorithms are derived in a unified framework, with pre-filtering, filtering, and post-filtering weights. Three viable weighting strategies are then presented including a classic one developed by Besson in the literature and two new ones generated from a curvature fitting and from an empirical formula, where all of the three weights can be expressed as certain functions of NROD. After that, an analysis of reconstruction accuracy is conducted with a wide range of NROD. We further stretch the weighted FBP-type algorithms to GEGCT with dynamic NROD. Finally, the weighted FBP algorithm for GEGCT is extended to a three-dimensional form in the case of cone-beam scan with a cylindrical detector array.Comment: 31 pages, 13 figure

A Review of 4DCT Imaging and Reconstruction Methods

In this paper, the main literature related to 4DCT imaging and reconstruction techniques over the past 20 years is reviewed, and the contents are summarized. This paper provides a systematic and comprehensive introduction to 4DCT research from five perspectives: the concept of 4DCT, scanning mode and imaging method, reconstruction algorithm, application, research status, and future development expectations. In this study, five types of reconstruction algorithms are summarized, and the advantages, disadvantages, and research difficulties of each algorithm are briefly evaluated. Finally, we conduct a brief statistical analysis on the cited works from the perspective of reconstruction methods, revealing the research progress and future research trends of 4DCT reconstruction algorithms

Factors influencing the continuance intention of the women’s health WeChat public account: an integrated model of UTAUT2 and HBM

BackgroundWomen’s health WeChat public accounts play a crucial role in enhancing health literacy and fostering the development of healthy behaviors among women by disseminating women’s health knowledge. Improving users’ continuous usage behavior and retention rates for the women’s health WeChat public account is vital for influencing the overall effectiveness of health communication on WeChat.ObjectiveThis study aimed to construct a comprehensive model, delving into the key factors influencing women’s continuance intention of the women’s health public accounts from the perspectives of perceived health threats, individual abilities, and technological perceptions. The goal is to provide valuable insights for enhancing user stickiness and the effectiveness of health communication on WeChat public accounts.MethodAn online survey was conducted among women receiving gynecological care at a certain hospital to gage their willingness for sustained use of the women’s health WeChat public accounts. Through structural equation modeling, the study investigated the influencing factors on women’s sustained intention to use the women’s health WeChat public accounts.ResultsThe study included a total of 853 adult women. Among them, 241 (28.3%) women had followed women’s health official accounts in the past but do not currently follow them, 240 (28.1%) women had followed women’s health official accounts in the past and are still following them, and 372 (43.6%) women had never followed women’s health official accounts. Currently, 240 women are still browsing women’s health public accounts, 52 of whom read women’s health public accounts every day, and most of them read women’s health public accounts for 10–20 min at a time (100, 11.7%). The results of the structural equation model revealed that performance expectancy, social influence, hedonic motivation, habit, and e-health literacy had significantly positive effects on women’s sustained intention to use public accounts (performance expectancy: β = 0.341, p < 0.001; social influence: β = 0.087, p = 0.047; hedonic motivation: β = 0.119, p = 0.048; habit: β = 0.102, p < 0.001; e-health literacy: β = 0.158, p < 0.001). E-health literacy and self-efficacy indirectly influence sustained intention by affecting performance expectancy, effort expectancy, social influence, facilitating conditions, hedonic motivation, and habit. The effect sizes of e-health literacy on performance expectancy, effort expectancy, social influence, facilitating conditions, hedonic motivation, and habit were 0.244 (p < 0.001), 0.316 (p < 0.001), 0.188 (p < 0.001), 0.226(p < 0.001), 0.154 (p < 0.001), and 0.073 (p = 0.046). The effect sizes of self-efficacy on performance expectancy, effort expectancy, social influence, facilitating conditions, hedonic motivation, and habit were 0.502 (p < 0.001), 0.559 (p < 0.001), 0.454 (p < 0.001), 0.662 (p < 0.001), 0.707 (p < 0.001), and 0.682 (p < 0.001). Additionally, perceived severity and perceived susceptibility indirectly affected sustained intention by influencing performance expectancy and social influence. The effect sizes of perceived severity on performance expectancy and social influence were 0.223 (p < 0.001) and 0.146 (p < 0.001). The effect size of perceived susceptibility to social influence was 0.069 (p = 0.042).ConclusionUsers’ e-health literacy, self-efficacy, perception of disease threat, and users’ technological perceptions of the WeChat public accounts are critical factors influencing women’s continuance intention of using the WeChat public accounts. Therefore, for female users, attention should be given to improving user experience and enhancing the professionalism and credibility of health information in public account design and promotion. Simultaneously, efforts should be made to strengthen users’ health awareness and cultivate e-health literacy, ultimately promoting sustained attention and usage behavior among women toward health-focused public accounts

Camera-based Mirror Visual Feedback: Potential to Improve Motor Preparation in Stroke Patients

© 2018 IEEE.Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Mirror visual feedback (MVF) is used widely for motor recovery after stroke, but an optimal training setup and systematic procedure are lacking. New optimization strategies have been proposed, one of which is a camera technique. We investigated the effects of a camera-based MVF setup on motor function and motor processes upstream for upper-limb rehabilitation. Seventy-nine stroke patients were assigned randomly to the MVF group (MG; N = 38) or conventional group (CG; N = 41), which respectively received camera-based MVF and dosage-equivalent physiotherapy or/and occupational therapy for 1 h/day and 5 days/week for 4 weeks. Two clinical scales were used to quantify the effect of the intervention methods: the Fugl–Meyer Assessment-Upper Limb (FMA-UL) subscale and Barthel Index (BI). The hand laterality task was used to evaluate the ability of mental rotation, including the reaction time (RT) and accuracy (ACC). All measurements improved significantly for both groups following intervention. FMA-UL was improved significantly in the MG compared with that in the CG. In lateralization tasks, the RT of the MG was significantly shorter than that of the CG at the endpoint. For all patients, judgments for the affected side were significantly slower and less accurate than for the less-affected side. Subgroup analyses suggested greater benefits of motor function, the activities of daily life, and mental rotation were achieved in subacute patients after MVF. A trend towards greater improvements in motor function for patients with severe–moderate motor impairment and patients with right-hemisphere damage were also revealed. Camera-based MVF improved the motor function and ability of mental rotation for stroke patients, especially for patients in the subacute stage, which indicates the potential to improve motor preparation. Further studies might combine mental rotation with electroencephalography to investigate the neuro-mechanism of MVF.Science and Technology Commission of Shanghai Municipality (15441901601, 16441905303)National Natural Science Foundation of China (61771313)National High Technology Research and Development Program of China (SS2015AA020501)Key Projects in the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period (2013BAI10B03)Natural Sciences andEngineering Research Council of Canada (072169