Purpose: In computed tomography, metallic objects in the scanning field create the so‐called metal artifacts in the reconstructed images. Interpolation‐based methods for metal artifact reduction (MAR) replace the metal‐corrupted projection data with surrogate data obtained from interpolation using the surrounding uncorrupted sinogram information. Prior‐based MAR methods further improve interpolation‐based methods by better estimating the surrogate data using forward projections from a prior image. However, the prior images in most existing prior‐based methods are obtained from segmented images and misclassification in segmentation often leads to residual artifacts and tissue structure loss in the final corrected images. To overcome these drawbacks, the authors propose a fusion scheme, named fusion prior‐based MAR (FP‐MAR). Methods: The FP‐MAR method consists of (i) precorrect the image by means of an interpolation‐based MAR method and an edge‐preserving blur filter; (ii) generate a prior image from the fusion of this precorrected image and the originally reconstructed image with metal parts removed; (iii) forward project this prior image to guide the estimation of the surrogate data using well‐developed replacement techniques. Results: Both simulations and clinical image tests are carried out to show that the proposed FP‐MAR method can effectively reduce metal artifacts. A comparison with other MAR methods demonstrates that the FP‐MAR method performs better in artifact suppression and tissue feature preservation. Conclusions: From a wide range of clinical cases to which FP‐MAR has been tested (single or multiple pieces of metal, various shapes, and sizes), it can be concluded that the proposed fusion based prior image preserves more tissue information than other segmentation‐based prior approaches and can provide better estimates of the surrogate data in prior‐based MAR methods.

In order to regulate turbulence strength and determine airflow characteristics in a new dual-feed rotor spinning unit, the internal flow field is investigated. A computational fluid dynamics technique is employed to numerically study the three-dimensional model of the internal airflow in the new design. The effects of air velocity variation on turbulence strength, negative pressure, Re, and wall pressure distribution are investigated based on simulation data and previous studies. The results show that the turbulence strength and Re increased with increase in inlet air velocity. Pressure profiles inside the rotor varied significantly with positive pressure observed at the channel exits. Minimal inlet velocity maintains the flow field in the rotor interior below 100 m/s, which gives the ideal turbulence required to minimize yarn quality deterioration. The dual-feed rotor spinning unit showed more orderly streamline patterns with fewer vortices compared to the conventional one. The numerical simulation can provide insights on airflow studies and some guidelines for future prototyping and experiments to further improve the new design.

Background: During interprofessional clinical practice, compared to understanding of one's own professional role and function, it might be more difficult to clarify the roles and contributions of the other health-care team members because of the inter-professional barrier. In order to provide students the opportunity for real experience with other professions in team environments and enhance their perceptions of other professions' roles, this study developed a comprehensive and multi-dimension extracurricular interprofessional education (IPE) model through designing and integrating a profession-role exchange component, that was medical students as pharmacists or nurses, pharmacy students as physicians or nurses, and nursing students as physicians or pharmacists in the interprofessional health-care student team, into the service learning experience in a real community setting. Methods: In this pre/post-intervention study, the effect of integrated profession-role exchange experiences on the students' attitudes towards interprofessional collaboration and their role clarification was evaluated among 60 student volunteers (20 medical students, 20 pharmacy students and 20 nursing students). All involved students were divided into the profession-role exchange intervention group and the control group. Subjects in the control group did not participate the profession-role exchange experiences, the other IPE procedures were the same for both groups. Three survey instruments for attitudes toward interprofessional clinical collaboration were respectively used to measure the students' attitudes toward physician-pharmacist, physician-nurse and nurse-pharmacist collaborations. "Roles and responsibilities" subscale of Readiness for Interprofessional Learning Scale was used to evaluate the overall role clarification during IPE. Results: Compared to the control IPE activity, the addition of profession-role exchange component resulted in the significant increase in students' positive attitudes towards interprofessional collaboration, and the enhancement of students' role awareness. Conclusions: The profession-role exchange might be more effective and better initiate students to the practice of interprofessional collaboration, and could be used as an effective IPE tool for improving the role awareness of health-care students.

The conventional rotor spinning unit generates flow vortices in the transfer channel upstream region which affect the fiber configuration and consequently yarn properties. Geometry and spinning parameters such as transfer channel length, inlet width, rotor outlet pressure, opening roller speed and diameter were found to be key parameters influencing airflow characteristics. To reduce the flow vortices in the upper stream region, modifications of the transfer channel were proposed, and their airflow fields were analyzed using Computational Fluid Dynamics (CFD). Three designs were studied; round transfer channel inlet, a bypass channel for extra air supply and one with both the bypass and the round inlet. Analysis of airflow revealed that the design with both round transfer channel inlet and a bypass proved to be very effective in properly directing the flow and minimizing vortices. The design was also characterized by smoother velocity streamlines and maximum mass flow across the transfer channel. A conventional rotor spinning unit was modified in which a round transfer channel inlet corner and a bypass channel were utilized to conduct the experimental tests. Three sets of yarn samples were produced using the conventional and modified rotor spinning units under different rotor speed conditions. Yarn properties were tested. Properties such as tenacity, CVm%, thin and thick places of the spun yarns produced by the new design improved compared to that of the conventional yarn.

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