3D Printed Medical Model to Resolve Cleft Alveolus Defect: A Case Study

3D printing or Additive Manufacturing (AM) technology has been in existence for more than 30 years. The footprint of this technology has been entered into almost each and every industry such as medical, dental, aerospace, construction, automobile, etc. One of the most benefited industries using AM is medical industry. In case of medical or maxillofacial surgical field, each and every patient has a unique anatomy. The traditional way of analyzing the patient anatomy was by using X-ray with single layer or CT scans with multiple layers information is available that too as soft data. 3D printing technology provides a physical model from virtual data of the patient anatomy using CT/MRI/CBCT information with the help of medical software. The physical 3D printed medical model is very useful for pre planning complex surgeries. The current case study is regarding a 35 years male patient, who presented with a defect in maxillary anterior alveolar region and nasal regurgitation of fluids. Based on chief complaint, history and clinical examination, a diagnosis of cleft alveolus was made. CT scan was advised to see the defect in all the 3 planes. The surgery was planned for reconstruction of the bony defect and to prevent escape of oral fluids into nasal cavity. Treatment planning and mock surgery were performed on the 3D printed medical model, which reduced about 30% of total surgery time thereby decreasing the complications

Estimation of Ice Basal Reflectivity of Byrd Glacier using RES data

Ice basal reflectivity is much needed for the determination of ice basal conditions and for the accurate modeling of ice sheets to estimate future global mean sea level rise. Reflectivity values can be determined from the received radio echo sounding data if the power loss caused by different components along the two-way transmission of electromagnetic waves is accurately compensated. For the large volume of received radio echo sounding data collected over Byrd glacier in 2011-2012 with a multichannel radar system, the spherical spreading loss caused due to two-way propagation, power reduction due to roughness and relative englacial attenuation is compensated to estimate the relative reflectivity values of the Byrd glacier ice base. In order to estimate the scattered incoherent power component due to roughness, the distributions of echo amplitudes returned from the air-firn interface and from the ice – bed interface are modeled to estimate RMS height variations. The englacial attenuation rate for two-way propagation along the ice depth is modeled using the collected radar data. The estimated air-firn interface roughness parameters are relatively cross verified using Neal’s method and with correlations to the Landsat image mosaic of Antarctica. Estimated relative basal reflectivity values are validated using cross-over analysis and abruptness index measurements. From the Byrd relative reflectivity map, the corresponding echograms at the locations of potential subglacial water systems are checked for observable lake features. The results are checked for correlations with previously predicted lake locations and subglacial flow paths. While the results do not exactly match with the previously identified locations with elevation changes, high relative reflectivity values are observed close to those locations, aligning exactly or close to previously predicted flow paths providing a new window into the subglacial hydrological network. Relative reflectivity values are clustered to indicate the different potential basal conditions beneath the Byrd glacier

Effect of Tissue Structure (and) Disease on Simulated Arrhythmias in the Human Heart

Ventricular Fibrillation (VF) is a severe cardiac arrhythmia. Early experiments provided evidence that the mechanism of VF is consistent with re-entry. In 3D the sources of re-entrant waves are lines of phase singularity called ‘filaments’. Filament interactions and filament numbers can be used to quantify the complexity of activation patterns in simulated VF. The aim of this thesis is to study the effect of tissue structure, shape, initial conditions, and region of scar on filament dynamics using computational modelling. Transmural heterogeneity in 3D slab tissue representing the ventricular wall did not show important difference in the number of filaments. Configuration of filaments were influenced by transmural heterogeneity. With transmural heterogeneity, clustering of filaments were observed near slow conducting border resulting in increase of filament life time. To study the effect on the shape of the tissue on filaments, filament dynamics in 3D slab tissue was compared with filament dynamics in an idealized human left ventricle (LV) with similar apex base dimension and wall thickness. The volume of idealized LV is about twice the volume of 3D slab. Results showed idealized LV had twice the number of filaments compared to slab geometry especially with steeper restitution dynamics. This thesis highlights non-linear behaviour of activation patterns during VF in 3D where small changes had a large influence on the number of filaments in both 3D slab and idealized LV especially with steeper restitution dynamics. Pre-existing scar tissue in VF patients can act as a source of anatomical re-entry and pin re-entrant filaments to the scar boundary. However, the interaction of scar with complex activation during VF is not well understood. This thesis investigated how simulated scars (circumferential, transmural and sub-endo transmural) with varying size and with either regular or with irregular scar boundary, influenced re-entrant filaments in simplified computational models of 3D slab and idealized LV. Circumferential scar did not show any influence on filament dynamics and clustering of filaments to scar boundary. Increased radius of transmural and sub-endocardial transmural scar had more clustering of filaments to the scar boundary especially with steeper restitution dynamics. Sub- endocardial transmural scar with increased radius had more clustering of filaments compared to transmural scar. Region of scar with irregular boundary had more clustering compared to scar with regular boundary. Generally transmural scar and sub-endocardial transmural scar with regular or irregular boundary did not increase the number of filaments much but increased the length and lifetime of filaments due to clustering of filaments to the scar boundary. Since filaments pin to the boundary of the scar region, it can be hard to remove them using defibrillation techniques. It might be necessary to measure the radius and the depth of pre-existing scar tissue accurately in VF patients, as the bigger scar is likely to have more complex activation in VF. In this way it might be easier to predict the strength of defibrillation to use, in order to stop VF

Empirical Correlations of Longwall Subsidence Data for the Illinois Coal Basin

Subsidence, mining and site data has been collected over a number of longwall panels in the Illinois Basin. Using this data, empirical correlations are attempted to various subsidence parameters, including maximum vertical and horizontal displacement, subsidence slope and curvature and horizontal strain. Also, the corresponding locations of these various subsidence characteristics are correlated to the associated site conditions. An extensive list of definitions are provided for the various subsidence parameters utilized in the paper

Improving Volumetric Accuracy of AM Part Using Adaptive Slicing of Octree Based Structure

In Additive Manufacturing (AM) processes, the layer-by-layer fabrication of complex geometries may lead to stair casing and thus error resulting in volumetric inaccuracies in the model. Using thinner slices reduces the staircase error and improves part accuracy but there is a tradeoff between number of layers and the build time for manufacturing part. This paper presents a octree based structure to improve the accuracy as well as reduces the build time. In the current work, firstly converting STL file into a modified boundary octree data structure (MBODS) and then calculating the non-uniform slice thicknesses (adaptive slicing) from the octree representation. This slice thickness at any height is computed from the AM machine parameters and the smallest octree size at that available height. After the computation of the variable slice thicknesses has been completed, the part is virtually manufactured and the part errors are calculated. The virtually manufactured part and physical models are inspected to evaluate the volumetric errors. This algorithm uses an octree approach to improve the volumetric accuracy. And build time for the two different case studies are also done.Mechanical Engineerin

Design and Development of Smart, Intelligent & LOT Enabled Remote Health Monitoring System

Drastic developments in the area of Wireless Sensor Networks (WSNs) have paved a path for ap- plications in so called Internet of Things (IoT). Some major applications include remote health monitoring, environment monitoring, smart grids etc. In this work we have identified the primary issues that IoT architectures are facing and developed a system architecture to address the issues identified. IoT architectures primarily face the power constraints due to their battery dependency in remote deployment such as remote health monitoring. Other issue is the hyper connectivity scenario, where the data generated by the sensor networks should have to be limited for efficient management of networks. The proposed architecture consists of an intelligent data transmission mechanism with smart sensing and IEEE 802.15.4 - PHY is considered for communication facility

A Authentication model to Trustees based Social Networks

authenticating users with the help of their friends has been shown to be a promising backup authentication mechanism. A user in this system is associated with a few trustees that were selected from the user’s friends. When the user wants to regain access to the account, the service provider sends different verification codes to user’s trustees. The user must obtain at least k reset his or her password. In this paper, we provide the first systematic study about the security of trustee based social authentications. In particular, we first introduce verification codes from the trustees before being directed to small framework of attacks, which attacks. In these attacks, an attacker initially obtains we call forest fire iteratively, attacks the rest of users by exploiting trustee-based social authentications. Then, we construct a probabilistic model to for attackers. Moreover, we introduce number of compromised users, and then the attacker a novel various defense formalize the threats of forest fire attacks and their costs strategies. Evaluate various concrete attack and defense our results have finally, we apply our framework to strategies using three real world social network datasets. Extensively strong implications for the design of more secure trustee-based social authentications

Design & Manufacturing of Implant for reconstructive surgery: A Case Study

Additive Manufacturing (AM), also known as 3D printing is an emerging technology in oral & maxillofacial surgery with respect to reconstructive bone surgery. Such treatment protocols often require customized implants to fulfill the functional and aesthetic requirements. Currently, such customized implants are being manufactured using AM technology. This paper describes a mandible defect of oral & maxillofacial surgery. The fracture and defect of the mandible inferior border is one of the serious complications during alignment and fixing of the implant. Reconstruction of such defects is daunting tasks. The case report describes a method based on Computer Aided Design (CAD) and AM for individual design, fabrication and implantation of a mandible inferior border. A 40-year old male meet an accident with rash drive. The patient specific customized implant is designed with patient Computed Tomography (CT) data. The CT images in Digital Imaging and Communication in Medicine (DICOM) file format is used to develop a 3D CAD model of customized implant. The implant is designed to maintain the symmetry of mandible from right to left. The designed implant model is manufactured by Fused Deposition Modelling (FDM) techniques with a biocompatible material. The patient mandible prototype model was manufactured by AM process, which is helpful for pre-planning of surgical procedures. For these pre-planning surgical procedures, a perfect fit obtained during surgery. The patient ultimately regained reasonable mandible contour and appearance of the face.

Recurrent pregnancy loss: challenge to obstetricians

Background: Recurrent pregnancies loss (RPL) is physically and emotionally devastating situation for the parents, along with difficult situation for obstetrician to handle. Present study aimed at investigation of the significance of various etiology in relation to pregnancy outcome in cases of recurrent pregnancy loss.Methods: It is a retrospective analysis of patients who presented to M. S. Ramaiah Medical college with recurrent miscarriage between April 2014 and August 2015. ANA was done on the basis of clinical and laboratory data which was obtained and eventually diagnosis was made. The study results were analysed in terms of term live births, maternal and fetal complications.Results: Out of the RPL cases that were studied, 78 patients came with recurrent pregnancy loss. Out of these cases, endocrine abnormalities, like diabetes mellitus and hypothyroidism were the maximum 26.92% and 12.82% respectively. Followed by unexplained causes were 37.3%. Thrombophila and APLA positive cases constituted for 16.66% and 3.4% respectively. ANA positive and cervical incompetence were 6.4% each.Conclusions: Recurrent pregnancy loss is very difficult situation to handle. Various etiology need various specialists, and requirements, and management mainly depends on the cause for recurrent pregnancy loss