Computationally efficient substrate noise coupling estimation in lightly doped silicon substrates

A Z-parameter based macromodel for characterizing the substrate noise coupling in a lightly doped substrate at low frequencies has been developed. The model is scalable with contact geometries and separation. The cross-coupling impedance between two contacts is modeled using an improved geometric mean distance formulation. This approach obviates the need for using several spacing related parameters for describing the contact separations, sizes, and orientation. An improved self-impedance model has also been developed. Proximity effects of neighboring contacts are taken into account by a paneling approach. The macromodel with paneling has been successfully used to predict the noise coupling for multi-contact examples. The errors from the macromodel relative to a numerical simulator are within acceptable limits of 15%

Postoperative acute parotitis after cesarean delivery under spinal anaesthesia: a rare entity

Postoperative acute painless parotid gland swelling, which is a rare complication has been reported after caesarian section (CS) under neuraxial anaesthesia. Here, we present a parturient who suffered from acute parotitis, which developed after elective repeat CS under spinal anaesthesia.

Copepod Abundance and Diversity from Offshore Region of Tuticorin, South East Coast of India

A detailed study had been carried out on species abundance, biomass and composition of copepod in four different offshore stations namely, Station I: Vembar, II: Keelavaipar, III: Punnaikayal and IV: Thiruchendhur in Gulf of Mannar region from October 2011 to April 2012. A total of 56 copepod species belongs to 20 families under 4 orders have been encountered during the period. The percentage composition of different groups of copepod species was composed of Calanoida (35 numbers) 62.5%, Cyclopoida (4 numbers) 7.14%, Harpacticoida (8 numbers) 14.3% and Poecilostomatoida (9 numbers) 16.1%. The percentage of biomass composition of different groups of copepods during the study was in the order of Calanoida 38.99%, Harpacticoida 32.56%, Cyclopoida 15.22% and Poecilostomatoida 13.23%. In the case of species composition, Euterpina acutifrons (28.61%) was the most abundant species followed by Acrocalanus gracilis (17.68%), Corycaeus crassiusculus (12.33%), Oithona brevicornis (12.03%) and Temora turbinata (4.25%) were the other dominant species in observation. The copepod density in different stations were in the range of 8600–39900, 3900–64600, 3800–24800 and 5000–22500 numbers m-3 at station I, II, II and IV respectively. The lowest biomass of copepod was observed at station III and highest biomass was found at station II. The copepod species richness ranged from 0.48 to 2.72 and species diversity was in the range of 0.87 to 1.98 in the study areas. Species evenness was varied from 0.24 – 0.51 during the observation period

Federated Learning Framework for IID and Non-IID datasets of Medical Images

Advances have been made in the field of Machine Learning showing that it is an effective tool that can be used for solving real world problems. This success is hugely attributed to the availability of accessible data which is not the case for many fields such as healthcare, a primary reason being the issue of privacy. Federated Learning (FL) is a technique that can be used to overcome the limitation of availability of data at a central location and allows for training machine learning models on private data or data that cannot be directly accessed. It allows the use of data to be decoupled from the governance (or control) over data. In this paper, we present an easy-to-use framework that provides a complete pipeline to let researchers and end users train any model on image data from various sources in a federated manner. We also show a comparison in results between models trained in a federated fashion and models trained in a centralized fashion for Independent and Identically Distributed (IID) and non IID datasets. The Intracranial Brain Hemorrhage dataset and the Pneumonia Detection dataset provided by the Radiological Society of North America (RSNA) are used for validating the FL framework and comparative analysis

ULTRASONOGRAPHIC AND HISOPATHOLOGICAL CHANGES IN DOGS WITH CHRONIC RENAL DISEASE

ABSTRAC

Applications of cone beam computed tomography in radiotherapy treatment planning.

In recent years Image-Guided Radiotherapy (IGRT) has experienced many technical advances. One of the most significant has been the widespread implementation of kilovoltage imagers attached to the gantry of linear accelerators (LINACs); these units are capable of 2D planar imaging, fluoroscopy and 3D Cone Beam Computed Tomography (CBCT) imaging. With CBCT imaging, the treatment plan can be modified based on patient’s anatomy just before the treatment session. This method of Adaptive Radiotherapy (ART) helps in managing a patient’s treatment by compensating for the effect of daily setup variation and changes to the tumour during the course of radiotherapy. Currently the image quality of CBCT is sufficient for patient set-up verification; however the use of CBCT for dose calculations requires reproducible CT numbers in order to be used effectively during ART. The aim of this project was to investigate methods to improve the image quality of CBCT datasets in order to facilitate their use in dosimetric calculations. The project was divided into two major parts. In the first part, the conventional Feldkamp-Davis-Kress (FDK) cone-beam reconstruction algorithm was implemented in Matlab. The algorithm was then modified using weighting factors for data redundancy and for nonequal cone angles. A 2D adaptive filter was used to remove noise and to compensate for the loss of resolution. A modified in-house reconstruction algorithm was developed and the image quality obtained was comparable to reconstructed images obtained using the Varian OBI system software. The images are free of crescent artifacts and showed a maximum spatial resolution of 7 line pairs/cm. The effect of different reconstruction filters on CBCT image quality was also studied and guidelines were produced for different anatomical sites to assist in choosing appropriate filters to achieve optimal reconstructed image quality. In the next part of the research, a comparative study between Varian and in-house reconstructed images was performed using Planning CT (PCT) images as a reference dataset. The feasibility of using the Varian and in-house reconstructed images for treatment planning was investigated by acquiring CBCT images of the Rando anthropomorphic phantom. An Intensity-Modulated Radiotherapy (IMRT) treatment plan was generated using both sets of reconstructed images using the Pinnacle3 treatment planning system. Planar dose distributions were extracted from both the datasets in order to evaluate dose distributions quantitatively based on 3%/3mm Gamma analysis criteria. These distributions were then compared against the reference PCT image and it was found that in-house reconstructed images showed good agreement with the PCT images with a gamma passing rate of 99.8%. Although several pre-processing steps performed on the Varian images were not included during in-house reconstruction, the results demonstrated the potential for use of in-house reconstructed CBCT image for treatment planning. As an alternative to FDK reconstruction, iterative reconstruction using Maximum Likelihood solutions was also investigated. Since the Ordered Subsets Expectation Maximisation (OSEM) package used in this study is intended for fan-beam geometry, only the slices from the central plane of cone-beam were chosen. The projections were corrected for distance-dependent resolution and centre of rotation offset. When the number of iterations was increased to 16, the algorithm converges well and showed more uniform images. However, the images were not comparable to FDK-based images due to the intrinsic difference in data handling. The OSEM program was developed initially for emission-based measurements and did not model the scatter component effectively for transmission-based measurements. Including the scatter component more effectively may make it more realistic for CBCT geometry.Thesis (M.Phil.) -- University of Adelaide, School of Chemistry and Physics, 201

Prostaglandin analogs in ophthalmology

Glaucoma is a major cause of irreversible blindness worldwide. Reducing intraocular pressure (IOP) is currently the only approach to prevent further optic nerve head damage. Pharmacotherapy is the mainstay of treatment for glaucoma patients. In recent years, a significant milestone in glaucoma treatment has been a transition to prostaglandin analogs (PGAs) as the first line of drugs. The rapid shift from traditional β-blockers to PGAs is primarily due to their excellent efficacy, convenient once-a-day usage, better diurnal control of IOP, and systemic safety profiles. This review article aims to provide information regarding the various PGAs in practice and also the newer promising drugs