ABSTRACT
The rotator cuff tear effects on glenohumeral joint tissues, such as superior labrum anterior-posterior (SLAP) lesions, have been studied experimentally or numerically in various cases. In relation to these studies, and as a novel feature of our study, infraspinatus (INF) muscle tear effects on other muscle force variations and stress and strain increases on glenoid labrum (GL), glenoid cartilage (GC) tissues, and a SLAP pathology were investigated. The ITK-SNAP Software (ISS) was used to segment the humerus and glenoid bone. The surface entities were segmented and exported to SolidWorks 2019, where the finite element model (FEM) was completed. Static optimizations of the muscle forces were calculated using a generic model in OpenSim 4.1 for the 0-3.88 s time interval to perform our finite element analyses (FEAs) in ANSYS 19.3 for the intact, partial torn, and fully torn INF muscle. The FEAs were also conducted for the specified time interval. The stress and strain increases on the GL, and GC tissues were determined to be critical when compared with yield strengths. In the case of fully torn INF, the GL and cartilage interfacial principal stress was calculated to be 3.3856 MPa. In the case of the fully torn INF, the principal stress that occurred on the GC tissue was calculated to be 42.465 MPa. In the case of the intact INF, the principal stress that occurred on the labrum was obtained as 4.257 MPa. These results showed that there was no detachment or disorder on the designated tissues caused by the INF muscle tear when the shoulder functioned at 60° of external rotation at 11° of abduction. Nonetheless, a minor amount of external force could cause severe pathological effects on the specified tissues.
Subject(s)
Finite Element Analysis , Rotator Cuff Injuries , Rotator Cuff , Stress, Mechanical , Rotator Cuff/pathology , Biomechanical Phenomena , Humans , Shoulder Joint/physiopathology , Mechanical PhenomenaABSTRACT
COVID-19 has engulfed over 200 nations through human-to-human transmission, either directly or indirectly. Reverse Transcription-polymerase Chain Reaction (RT-PCR) has been endorsed as a standard COVID-19 diagnostic procedure but has caveats such as low sensitivity, the need for a skilled workforce, and is time-consuming. Coronaviruses show significant manifestation in Chest X-Ray (CX-Ray) images and, thus, can be a viable option for an alternate COVID-19 diagnostic strategy. An automatic COVID-19 detection system can be developed to detect the disease, thus reducing strain on the healthcare system. This paper discusses a real-time Convolutional Neural Network (CNN) based system for COVID-19 illness prediction from CX-Ray images on the cloud. The implemented CNN model displays exemplary results, with training accuracy being 99.94% and validation accuracy reaching 98.81%. The confusion matrix was utilized to assess the models' outcome and achieved 99% precision, 98% recall, 99% F1 score, 100% training area under the curve (AUC) and 98.3% validation AUC. The same CX-Ray dataset was also employed to predict the COVID-19 disease with deep Convolution Neural Networks (DCNN), such as ResNet50, VGG19, InceptonV3, and Xception. The prediction outcome demonstrated that the present CNN was more capable than the DCNN models. The efficient CNN model was deployed to the Platform as a Service (PaaS) cloud.
ABSTRACT
Transient and residual stresses occurring in partially fixed dental prostheses after the firing process can be calculated with elastic or elastic-plastic finite element analyses (FEA). In this study, firstly, the mechanical and thermal properties at various temperatures of the materials used in a porcelain fused metal (PFM) system were obtained by experimental and literature studies. The effects of viscoelastic and viscoplastic behaviours of the dental porcelain at the elevated temperatures were reflected onto its elastic properties. The equivalent heat transfer coefficients were determined experimentally by measuring temperatures and the results were supplied as input to the 3D finite elements analysis. It has been observed that the maximum stresses occur within a short time period after cooling begins and that stresses decrease during the cooling process and remain at a constant value at the end of cooling; these are the thermal residual stresses.