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Objective The current secondary positioning system of urban rail transit train beacons has a positioning accuracy of 300 meters, failing to meet the high-precision positioning requirements of wireless environment monitoring grid. Additionally, GPS (global positioning system) and the Beidou Satellite Navigation System are not suitable for underground rail positioning. Therefore, it is necessary to conduct in-depth research on continuous positioning technology for urban rail transit CBTC (communication-based train control) wireless environment monitoring grid. Method Building on the existing urban rail transit train beacon secondary positioning system, an inertial navigation technology enhanced by beacon-assisted training is adopted. By utilizing a multi-sensor fusion positioning algorithm, the sensor data from the inertial navigation module is integrated with the beacon data from the ATS (automatic train supervision) system, thus achieving the continuous positioning of wireless environment monitoring grid in urban rail transit. Additionally, a regression prediction algorithm is used for offline model training to enhance the accuracy of continuous positioning for the urban rail transit wireless environment monitoring grid. Result & Conclusion The proposed methods can achieve continuous and real-time positioning of wireless environment monitoring grid, supporting CBTC wireless environment monitoring grid in tunnels, beneath elevated structures, and in complex environments where metro train passing through areas with tall buildings and tree cover. The positioning accuracy reaches 10 m, meeting the positioning requirements of the CBTC wireless environment monitoring system, and fully ensuring the safety of the urban rail transit CBTC signaling system.

Faculty members abruptly transitioned to online course delivery during the COVID-19 public health crisis. Unfortunately, the isolation of learning online had the potential to damage students' well-being during an already stressful pandemic. Furthermore, many faculty members had little experience with online modes of instruction and few effective strategies for building community online. This exploratory sequential mixed methods study uses data from 37 individual interviews with faculty across diverse disciplines, course evaluations from 13 of the 37 interview participants, and survey data from 347 faculty to answer the following research question: "How did faculty foster a sense of community online to support students' holistic well-being during the COVID pandemic? What strategies can faculty use to create community and foster well-being in online courses?" Results show that successful strategies centered around intentional and purposeful course design, establishing clear expectations for faculty and students, and fostering supportive and trustworthy online learning environments.

PURPOSE We aimed to investigate the safety and tumor seeding rate of a coaxial implantation technique combined with injection of a gelfoam pellet in establishing a VX2 liver tumor model in rabbits. METHODS A VX2 liver tumor model was established in 60 male New Zealand white rabbits, which were randomly divided into 3 groups (20 in each group) based on implantation technique (all performed under ultrasound guidance): group A, single needle only; group B, single needle with injection of a gelfoam pellet; or group C, coaxial technique with injection of a gelfoam pellet. The rates of liver tumor formation and tumor seeding to extrahepatic tissues were compared 2 weeks after implantation. Data were also collected regarding procedure time, number of punctures, occurrence of complications, and mortality rate. RESULTS A VX2 liver tumor model was established in all 60 rabbits (100%, 60/60). Ectopic implantation rate was 70% (14/20) in group A, 35% (7/20) in group B, and 5% (1/20) in group C, with significant difference among the groups (p < 0.001). Post hoc analysis showed significant difference between group A and group C (p < 0.001). However, there were no significant differences between group B and group A or group C (p = 0.027, p = 0.048, respectively). There were no significant differences among the groups in terms of procedure time (p = 0.405) or number of punctures (p = 0.612). No complications or deaths occurred. CONCLUSION A coaxial technique with injection of a gelfoam pellet is an effective and safe method for VX2 liver tumor implantation in rabbits, and this technique can reduce the risk of tumor seeding to the abdominal wall and omentum. [ABSTRACT FROM AUTHOR]

AbstractUrban expansion models (UEMs) help unfold the mechanism, future pathways, and relevant repercussions of urban landscape dynamics. Although a plethora of UEMs have been developed, the field of open-access modeling platform for urban expansion simulation still presents gaps in terms of representing urban development events, regulating multilevel urban morphologies, and reflecting underlying regularities of physical urban growth. This study develops an open-access Multiengine Urban Expansion Simulation (MUSE) platform together with software that addresses some of these limitations. MUSE employs patch-based concepts and different patch generation engines to represent urban development events of distinctive types, enabling control over spatial morphology at landscape, class and patch levels. Moreover, MUSE incorporates two general regularities on urban development waves and urban diffusion and coalescence to govern physical urban expansion processes. Experiments in two cities examine MUSE’s ability in simulating realistic urban dynamics, and a series of synthetic experiments verify the operational behavior of the patch generation engines. These experiments show that MUSE can simulate a range of urban expansion types, including infill, edge growth and leapfrog expansion, and various morphologies, such as aggregated, sprawl, fragmented and compact. MUSE can empower practitioners to better project, analyze and understand complex urbanization dynamics. [ABSTRACT FROM AUTHOR]

Objective: This retrospective study aimed to investigate the clinical efficacy and safety of carotid artery stenting (CAS) in elderly patients with internal carotid artery stenosis (ICS)., Methods: Ninety elderly ICS patients admitted between January 2019 - July 2021 were selected and divided into a control group and a research group according to different treatment method. The 42 cases in the control group were received carotid endarterectomy and the 48 cases in the research group were treated with CAS. The effects of the two intervention methods on the National Institutes of Health Stroke Scale (NIHSS) score, complication rate, oxidative stress, inflammatory cytokines and cognitive function were observed and evaluated., Results: Compared to baseline (before treatment), the research group showed significantly reduced scores of NIHSS and activities of daily living, appreciably decreased levels of malonaldehyde, interleukin-6 and high-sensitivity C-reactive-protein, but increased superoxide dismutase, Rapid Verbal Retrieve score and Digit Span Test score after treatment. Also, the same trends were found when comparing the above results with those of the control group after treatment. The two groups showed a comparable complication rate., Conclusions: The above data indicate a definite clinical efficacy and a favorable safety profile of CAS for ICS in the elderly. CAS can effectively reduce the oxidative stress and inflammatory cytokines of patients and enhance their cognitive function., Competing Interests: None., (AJTR Copyright © 2022.)

PURPOSE We aimed to investigate the safety and tumor seeding rate of a coaxial implantation technique combined with injection of a gelfoam pellet in establishing a VX2 liver tumor model in rabbits. METHODS A VX2 liver tumor model was established in 60 male New Zealand white rabbits, which were randomly divided into 3 groups (20 in each group) based on implantation technique (all performed under ultrasound guidance): group A, single needle only; group B, single needle with injection of a gelfoam pellet; or group C, coaxial technique with injection of a gelfoam pellet. The rates of liver tumor formation and tumor seeding to extrahepatic tissues were compared 2 weeks after implantation. Data were also collected regarding procedure time, number of punctures, occurrence of complications, and mortality rate. RESULTS A VX2 liver tumor model was established in all 60 rabbits (100%, 60/60). Ectopic implantation rate was 70% (14/20) in group A, 35% (7/20) in group B, and 5% (1/20) in group C, with significant difference among the groups (p < 0.001). Post hoc analysis showed significant difference between group A and group C (p < 0.001). However, there were no significant differences between group B and group A or group C (p = 0.027, p = 0.048, respectively). There were no significant differences among the groups in terms of procedure time (p = 0.405) or number of punctures (p = 0.612). No complications or deaths occurred. CONCLUSION A coaxial technique with injection of a gelfoam pellet is an effective and safe method for VX2 liver tumor implantation in rabbits, and this technique can reduce the risk of tumor seeding to the abdominal wall and omentum.