Search

PurposeTo extend the MR MultiTasking-based Multidimensional Assessment of Cardiovascular System (MT-MACS) technique with larger spatial coverage and water-fat separation for comprehensive aortocardiac assessment.MethodsMT-MACS adopts a low-rank tensor image model for 7D imaging, with three spatial dimensions for volumetric imaging, one cardiac motion dimension for cine imaging, one respiratory motion dimension for free-breathing imaging, one T2-prepared inversion recovery time dimension for multi-contrast assessment, and one T2*-decay time dimension for water-fat separation. Nine healthy subjects were recruited for the 3T study. Overall image quality was scored on bright-blood (BB), dark-blood (DB), and gray-blood (GB) contrasts using a 4-point scale (0-poor to 3-excellent) by two independent readers, and their interreader agreement was evaluated. Myocardial wall thickness and left ventricular ejection fraction (LVEF) were quantified on DB and BB contrasts, respectively. The agreement in these metrics between MT-MACS and conventional breath-held, electrocardiography-triggered 2D sequences were evaluated.ResultsMT-MACS provides both water-only and fat-only images with excellent image quality (average score=3.725/3.780/3.835/3.890 for BB/DB/GB/fat-only images) and moderate to high interreader agreement (weighted Cohen's kappa value=0.727/0.668/1.000/1.000 for BB/DB/GB/fat-only images). There were good to excellent agreements in myocardial wall thickness measurements (intraclass correlation coefficients [ICC]=0.781/0.929/0.680/0.878 for left atria/left ventricle/right atria/right ventricle) and LVEF quantification (ICC=0.716) between MT-MACS and 2D references. All measurements were within the literature range of healthy subjects.ConclusionThe refined MT-MACS technique provides multi-contrast, phase-resolved, and water-fat imaging of the aortocardiac systems and allows evaluation of anatomy and function. Clinical validation is warranted.

Purpose: Knee arthroplasty and hip arthroplasty (THA) patients are susceptible to post-operative venous thromboembolism(VTE). Doctors are increasingly recommending the application of different thromboprophylaxis agents such as rivaroxaban. The agents are primarily effective in preventing thromboembolism after hip and knee arthroplasty. Similarly, recent research suggests aspirin as one of the cost-effective interventions for preventing thromboembolism. Accordingly, this meta-analysis aims to compare the effectiveness of Aspirin against Rivaroxaban for the prevention or treatment of thromboembolism following knee arthroplasty and knee arthroplasty.Methods: The researcher relied on electronic searches of about five databases. The database searches identified relevant studies used to extract meta-analyzed data and information. The databases included PubMed, Cinahl, Medicine, Cochrane Database of Systematic Reviews(CDSR), Pharma GKB, SAGE, from inception to December 2020.Results: Different studies from the five databases we are included in this study. The studies include 2257 in the aspirin group and 2337 in the rivaroxaban group. The result revealed no significant difference between Aspirin and Rivaroxaban for the treatment of venous thromboembolism.Conclusion: The meta-analysis result affirmed no statistically significant difference between Aspirin and Rivaroxaban in preventing venous thromboembolism, a joint arthroplasty, or hip fracture surgery. However, some health care professionals find aspirin a more effective, safe, convenient, and affordable alternative for preventing venous thromboembolism. Thus the meta-analysis recommends extensive randomized studies to confirm the stipulated outcomes.

Background Each year around the globe, thousands of people are affected by Dengue fever. Dhaka is a very highly populated city. The rate of Dengue transmission in Dhaka is increased over the year. Authority takes numerous steps to reduce the Dengue transmission. Nevertheless, without proper Knowledge of folks on Dengue government may not alone prevent Dengue. In these circumstances, this paper will find out the Knowledge, Attitude and Practice among Dhaka people. This study will help policymakers access the KAP among the people and set goals to improve the Dengue prevention program. Methods This study determines 57 questions under three components. Preliminary data were collected from Dhaka dwellers throughout the internet survey using convenience sampling is a non-chance sampling method. The mean value of variables and Standard deviation (SD) is used to investigate the characteristics of the Socio-demographic profile of the sample. The data were analyzed using the Pearson correlation and regression method. Results The study finds that in Dhaka, urban people have much better KAP of Dengue than people who live in the countryside area. Between Male and Female at Dhaka, male does have much better KAP rather than women. Gender influences the practice level regarding DHF but does not affect the Knowledge and Attitude towards DHF. That means people's Income can change the knowledge level on DHF. People affected by Dengue fever at any stage of life have a better understanding of KAP than people do who are never affected by Dengue fever. People affected by Dengue fever at any stage of life have a better understanding of KAP than people do who are never affected by Dengue fever. Conclusion This study will help the dengue prevention in Dhaka and will help to increase the KAP towards the general people

The backbone of traditional CNN classifier is generally considered as a feature extractor, followed by a linear layer which performs the classification. We propose a novel loss function, termed as CAM-loss, to constrain the embedded feature maps with the class activation maps (CAMs) which indicate the spatially discriminative regions of an image for particular categories. CAM-loss drives the backbone to express the features of target category and suppress the features of non-target categories or background, so as to obtain more discriminative feature representations. It can be simply applied in any CNN architecture with neglectable additional parameters and calculations. Experimental results show that CAM-loss is applicable to a variety of network structures and can be combined with mainstream regularization methods to improve the performance of image classification. The strong generalization ability of CAM-loss is validated in the transfer learning and few shot learning tasks. Based on CAM-loss, we also propose a novel CAAM-CAM matching knowledge distillation method. This method directly uses the CAM generated by the teacher network to supervise the CAAM generated by the student network, which effectively improves the accuracy and convergence rate of the student network., Comment: Accepted by ICCV2021

PurposeTo develop an MR multitasking-based multidimensional assessment of cardiovascular system (MT-MACS) with electrocardiography-free and navigator-free data acquisition for a comprehensive evaluation of thoracic aortic diseases.MethodsThe MT-MACS technique adopts a low-rank tensor image model with a cardiac time dimension for phase-resolved cine imaging and a T2 -prepared inversion-recovery dimension for multicontrast assessment. Twelve healthy subjects and 2 patients with thoracic aortic diseases were recruited for the study at 3 T, and both qualitative (image quality score) and quantitative (contrast-to-noise ratio between lumen and wall, lumen and wall area, and aortic strain index) analyses were performed in all healthy subjects. The overall image quality was scored based on a 4-point scale: 3, excellent; 2, good; 1, fair; and 0, poor. Statistical analysis was used to test the measurement agreement between MT-MACS and its corresponding 2D references.ResultsThe MT-MACS images reconstructed from acquisitions as short as 6 minutes demonstrated good or excellent image quality for bright-blood (2.58 ± 0.46), dark-blood (2.58 ± 0.50), and gray-blood (2.17 ± 0.53) contrast weightings, respectively. The contrast-to-noise ratios for the three weightings were 49.2 ± 12.8, 20.0 ± 5.8 and 2.8 ± 1.8, respectively. There were good agreements in the lumen and wall area (intraclass correlation coefficient = 0.993, P < .001 for lumen; intraclass correlation coefficient = 0.969, P < .001 for wall area) and strain (intraclass correlation coefficient = 0.947, P < .001) between MT-MACS and conventional 2D sequences.ConclusionThe MT-MACS technique provides high-quality, multidimensional images for a comprehensive assessment of the thoracic aorta. Technical feasibility was demonstrated in healthy subjects and patients with thoracic aortic diseases. Further clinical validation is warranted.

Defects of polymer-derived Si−C−O fibers were intensively studied by the SEM and TEM techniques and their originations were also discussed on the basis of factors experiments. The defects were found mainly in the form of strumaes, pits and splits on surfaces as well as microflaw networks, porosity clusters and inclusions in the bulk. Factors experiments reveal that a nonuniform or an insufficient curing would result in larger-sized strumaes or interior microflaws. Gas evolution rates due to different firing rates have a great influence on the formation of internal microflaws or porosity clusters and some oxidation-induced pits or splits may be formed on surfaces because of a trace of oxygen or water vapor accumulated from the flowing inert atmosphere during pyrolysis.