An Information Theoretic Approach For Feature Selection And Segmentation In Posterior Fossa Tumors

Posterior Fossa (PF) is a type of brain tumor located in or near brain stem and cerebellum. About 55% - 70 % pediatric brain tumors arise in the posterior fossa, compared with only 15% - 20% of adult tumors. For segmenting PF tumors we should have features to study the characteristics of tumors. In literature, different types of texture features such as Fractal Dimension (FD) and Multifractional Brownian Motion (mBm) have been exploited for measuring randomness associated with brain and tumor tissues structures, and the varying appearance of tissues in magnetic resonance images (MRI). For selecting best features techniques such as neural network and boosting methods have been exploited. However, neural network cannot descirbe about the properties of texture features. We explore methods such as information theroetic methods which can perform feature selection based on properties of texture features. The primary contribution of this dissertation is investigating efficacy of different image features such as intensity, fractal texture, and level - set shape in segmentation of PF tumor for pediatric patients. We explore effectiveness of using four different feature selection and three different segmentation techniques respectively to discriminate tumor regions from normal tissue in multimodal brain MRI. Our research suggest that Kullback - Leibler Divergence (KLD) measure for feature ranking and selection and Expectation Maximization (EM) algorithm for feature fusion and tumor segmentation offer the best performance for the patient data in this study. To improve segmentation accuracy, we need to consider abnormalities such as cyst, edema and necrosis which surround tumors. In this work, we exploit features which describe properties of cyst and technique which can be used to segment it. To achieve this goal, we extend the two class KLD techniques to multiclass feature selection techniques, so that we can effectively select features for tumor, cyst and non tumor tissues. We compute segemntation accuracy by computing number of pixels segemented to total number of pixels for the best features. For automated process we integrate the inhomoheneity correction, feature selection using KLD and segmentation in an integrated EM framework. To validate results we have used similarity coefficients for computing the robustness of segmented tumor and cyst

The Burden of Inclusion: The Case of Saron Gebresellassi and Women of Colour in Municipal Politics

Substantial media and academic attention have been given to the concept of diversity nowadays, namely the participation of migrants and minorities within Canadian politics. While there is some discussion about the representation of women in municipal government, there is even less dialogue about the inclusion of women of colour in local arenas. Indigenous, racialized, and immigrant women are underrepresented at all levels of the government. By using the frameworks of anti-racist feminism and intersectionality, this paper will analyze the barriers faced by women of colour in the duration of their municipal campaign. Specifically, this paper will analyze the 2018 campaign of Toronto mayoral candidate, Saron Gebresellassi, and provide an analysis of her struggles with the following barriers: lack of public and media recognition, lack of financial resources, and the refusal to recognize her leadership. In so doing, this paper will demonstrate that women of colour continue to face barriers in the local political arena as a result of their identity yet are expected to futilely assert themselves in such spaces

Theoretical modal analysis of freely and simply supported RC slabs

This paper focuses on the dynamic behavior of reinforced concrete (RC) slabs. Therefore, the theoretical modal analysis was performed using two different types of boundary conditions. Modal analysis method is the most important dynamic analyses. The analysis would be modal case when there is no external force on the structure. By using this method in this paper, the effects of freely and simply supported boundary conditions on the frequencies and mode shapes of RC square slabs are studied. ANSYS software was employed to derive the finite element model to determine the natural frequencies and mode shapes of the slabs. Then, the obtained results through numerical analysis (finite element analysis) would be compared with the exact solution. The main goal of the research study is to predict how the boundary conditions change the behavior of the slab structures prior to performing experimental modal analysis. Based on the results, it is concluded that simply support boundary condition has obvious influence to increase the natural frequencies and change the shape of the mode when it is compared with freely supported boundary condition of slabs. This means that such support conditions have the direct influence on the dynamic behavior of the slabs. Thus, it is suggested to use free-free boundary condition in experimental modal analysis to precisely reflect the properties of the structure. By using free-free boundary conditions, the influence of poorly defined supports is interrupted

Experimental modal analysis of reinforced concrete square slabs

The aim of this paper is to perform experimental modal analysis (EMA) of reinforced concrete (RC) square slabs. EMA is the process of determining the modal parameters (Natural Frequencies, damping factors, modal vectors) of a structure from a set of frequency response functions FRFs (curve fitting). Although, experimental modal analysis (or modal testing) has grown steadily in popularity since the advent of the digital FFT spectrum analyzer in the early 1970’s, studying all types of members and materials using such method have not yet been well documented. Therefore, in this work, experimental tests were conducted on RC square slab specimens of dimensions 600mm x 600mmx 40mm. Experimental analysis was based on freely supported boundary condition. Moreover, impact testing as a fast and economical means of finding the modes of vibration of a structure was used during the experiments. In addition, Pico Scope 6 device and MATLAB software were used to acquire data, analyze and plot Frequency Response Function (FRF). The experimental natural frequencies which were extracted from measurements exhibit good agreement with analytical predictions. It is showed that EMA method can be usefully employed to investigate the dynamic behavior of RC slabs

An Examination of the Moderating Effect of Intergroup Anxiety on the Relationship between Intergroup Contact and Islamophobia

The terrorist attacks of 9/11 have led to feelings of disdain against Islam and have perpetuated Islamophobia in America. Research suggests that intergroup contact can help improve intergroup relations and reduce both prejudice and discrimination against members of out-groups. The purpose of this study was to determine whether or not intergroup anxiety moderates the relationship between intergroup contact and Islamophobia. Research has shown that intergroup anxiety has been associated with increased negative attitudes toward Muslims, but that reduced levels of intergroup anxiety lead to increased intergroup contact with Muslims and improved out-group attitudes. Participants included 214 community members of various liberal and conservative forums. Participants were given an online survey, which included a demographic questionnaire and measures on Islamophobia, intergroup contact, and intergroup anxiety. The hypotheses for this study were: 1) intergroup contact, as well as factors such as race, religious orientation, political orientation and media exposure will be significant predictors of Islamophobia; 2) intergroup anxiety will moderate the relationship between intergroup contact and Islamophobia. Results indicated that as contact with Muslims increases, Islamophobia decreases. Results also suggested that Republicans and participants that rely on Fox News for their main source of news tend to be Islamophobic. Furthermore, results indicated that intergroup anxiety does not moderate the relationship between intergroup contact and Islamophobia. However, results determined that participants who experienced intergroup anxiety were more likely to be Islamophobic. The findings of this study may serve to stimulate research on Islamophobia and address the various components that influence it

ANALYSIS OF ILLICIT DRUGS AND NICOTINE IN A BUCCAL TOBACCO BRAND MARKETED IN YEMEN

Objectives: The objective of the present study was to check the potential presence of illicit drugs and to quantify the amount of nicotine in a buccal tobacco brand that had been observed to be increasingly used by Yemeni youths, since 2014, causing narcosis resembling states among them. Methods: Thin-layer chromatography (TLC) described by the United Nations Office on Drugs and Crime (UNODC) was used to screen illicit drugs in the tested brand. The illicit drugs investigated included opiates, heroin, amphetamines, and cocaine. The TLC results were confirmed as recommended by the UNODC using color chemical tests. Identification and quantification of nicotine in the brand was carried out using an appropriate high-performance liquid chromatography (HPLC) system. Results: No illicit drug was found in the tested tobacco brand. On the other hand, it was found that the amount of nicotine in just a single dose (sachet) of the buccal brand was 17.67±0.901 mg, which was 3.53-fold greater than usual buccal dose of nicotine (5 mg). Conclusion: With the exception of cannabis, opioids, and hallucinogens that were not investigated in this study due to technical obstacles, other major illicit narcotic drugs are not found in the brand. The brand contains high amount of nicotine/sachet. However, knowing that the user may use more than one sachet of the brands a day, there is a great potential of nicotine overdosing due to intake of the brand. This may cause a narcosis resembling state called “Nesbitt’s paradox,” characterized by reducing neuronal activity of the user

Laparoscopic sleeve gastrectomy using a synthetic bioabsorbable staple line reinforcement material: Post-operative complications and 6 year outcomes.

BACKGROUND: Gastric leak after laparoscopic sleeve gastrectomy (LSG) is a serious complication. Currently, the literature lacks long-term outcomes in LSG and leak rates after reinforcement of the staple line. The aims are two-fold: to present leak rates from using staple line reinforcement and six year outcomes of LSG in relation to resolution of obesity-related comorbidities and long-term weight loss. MATERIALS AND METHODS: This is a single-institution, retrospectively reviewed study of 204 patient case files. Data from all patients undergoing LSG between December 2007 and May 2013 was collected. RESULTS: The total complication rate was 6.9% (14/204), with no recorded staple line leaks. The mean postoperative Body Mass Index (BMI) at 1 year, 2 years, 3 years, 4 years, 5 years, and 6 years was 39.3 ± 8, 38.7 ± 8, 40.4 ± 9, 40.5 ± 10, 43.0 ± 10, and 42.4 ± 7, respectively. The mean % excess weight loss at 1 year, 3 years, and 6 years was 48.4 ± 19, 51.7 ± 28, and 41.0 ± 21, respectively. There were no significant differences between follow-ups at year 1 and 3 (p > 0.05), and between year 3 and 6 (p > 0.05) for the mean % excess weight loss. The resolution rates for all patients were 74%, 61%, 79%, and 90% for hypertension, hypercholesterolemia, diabetes mellitus type 2 and obstructive sleep apnea, respectively. CONCLUSION: The synthetic bioabsorbable reinforcement material shows no staple line leaks making it safe to use. LSG as a procedure had a high resolution of obesity-related comorbidities as well as sustainable long-term weight loss

Recent Developments of Carboxymethyl Cellulose.

Carboxymethyl cellulose (CMC) is one of the most promising cellulose derivatives. Due to its characteristic surface properties, mechanical strength, tunable hydrophilicity, viscous properties, availability and abundance of raw materials, low-cost synthesis process, and likewise many contrasting aspects, it is now widely used in various advanced application fields, for example, food, paper, textile, and pharmaceutical industries, biomedical engineering, wastewater treatment, energy production, and storage energy production, and storage and so on. Many research articles have been reported on CMC, depending on their sources and application fields. Thus, a comprehensive and well-organized review is in great demand that can provide an up-to-date and in-depth review on CMC. Herein, this review aims to provide compact information of the synthesis to the advanced applications of this material in various fields. Finally, this article covers the insights of future CMC research that could guide researchers working in this prominent field

Optimization of Steam Distillation of Essential Oil of Eucalyptus tereticornis by Response Surface Methodology

This paper deals with optimization of yield of Eucalyptus tereticornis oil in steam distillation using response surface methodology (RSM). The factors considered were mass of solute/solvent ratio (A), extraction time (B) and steam rate (C). These parameters were varied at two levels. Conditions of optimum oil yield predicted were 105 min of extraction time and 0.032 kg/h steam rate. These factors gave an optimum oil yield of 2.05 %. Significant model terms were time, steam rate, and the interactions between them. Analysis of variance (ANOVA) indicates that the model was significant as evidenced from R2 of 0.9844 and the model F-value of 49.13. The oil yield predicted by the model was closed to the experimentally determined values (1.85 % and 1.87 % respectively); hence the model can be used for prediction of oil yield in essential oil extraction from E. tereticornis leaf via steam distillation method.Keywords: RSM, Eucalyptus tereticornis, steam distillation, Box-Bohnke