A study of factors contributing to the success of female Aboriginal students in an inner city high school

This study was based on the premise that Aboriginal students possess valuable knowledge and insights with regard to factors leading to their educational success. This study was qualitative research using a narrative approach in the form of sharing circles. It was a study of factors five female Aboriginal high school students, who anticipated graduating in June 2002, identified as contributing to their success in school. Traditionally, researchers have focused on factors contributing to the failure of Aboriginal students in high school. Their analysis have proven futile in decolonizing and reconstructing conventional education.The purpose of this study was to give students a voice in their education and in this voice, identify factors which contributed to their success. The data gathered through the collective voice of the students will assist educators and parents in challenging the educational system to satisfy the needs of all students, Aboriginal and non-Aboriginal. The unexpected composition of five female participants allowed the study to touch on issues facing Aboriginal women in school. These factors included the strong support of family, the nurturing roles that that engenders in them and their desire to bear children in the future, and the wish to break the cycle of social assistance by obtaining an education.The information collected in the sharing circles was analyzed from a traditional medicine wheel framework. The themes and sub-themes, which developed from the data, created the elements of a medicine wheel which will bring balance and harmony to the educational system. The participants identified a strong inner support system characterized by goals and the search for a gift. The strength of their inner being fueled their will to succeed.Their volition was further strengthened by factors found within the four realms of the medicine wheel: spiritual, emotional, physical, mental. The students identified spirituality as a combination of Aboriginal and Catholic teachings. This was characteristic of a new social environment which taught a freedom to live within two ideals of spirituality. In the emotional realm the students identified family, friends and development of self-identity as factors contributing to their success. The physical realm outlined the role multiculturalism had in the school, support programs played in making success a reality, and drug and alcohol avoidance had in their ability to succeed. The participants described Aboriginal teacher support, an engaging curriculum, and a grade twelve diploma as factors leading to success in the mental realm. Overwhelmingly, the factor most effecting the educational success of the participants was the teacher. All of the students described the positive and negative effect teachers had on their education. The teacher who supported the students in the four realms of the medicine wheel encouraged success in the classroom. The teachers who did not support the students provided a roadblock to success which the students overcame with perseverance and determination.The study suggests the need for future research in the area of Aboriginal and non Aboriginal success factors. Many factors identified within this study indicates a strong commonality between the needs of Aboriginal and non-Aboriginal students in school. An examination of this type would serve to deconstruct the degree of difference assigned between students of different ethnic backgrounds. The data provided calls for more research on the relationships of Aboriginal and non-Aboriginal teachers within schools. Lastly, the data provided by the students strongly indicates administrators must work to prepare teachers to be more supportive to student needs.This study provides some insights for educators, parents and administrators. Unfortunately the students, who are the most important part of the study, can only share their collective voice. The real work of transforming the educational system to meet the needs of Aboriginal students must come from educators, parents and administrators

HPLC assessment and multivariate predictability of serum retinol and α-tocopherol concentrations in adult female subjects

Antioxidant vitamins have been reported to protect against a variety of human malignances and multiple chronic degenerative diseases therefore it is important to understand factors that influence their blood levels. The present study was conducted to verify association of serum retinol and α-tocopherol levels with obesity, and to assess predictors of their serum concentrations in representative sample population of overweight/obese (n = 51) and normal weight (n = 26) apparently healthy adult female subjects recruited from typical urban area in Poland. Anthropometric measurements were taken from all participants who also completed a questionnaire on selected lifestyle factors. The serum concentrations of retinol and α-tocopherol were measured by fully validated Chromsystems diagnostic kit employing isocratic RPHPLC with switched wavelength UV detection. Intake of energy, fat, vitamin A and E and alcohol consumption were estimated by seven daily dietary records. Multivariate linear regression models were fitted in order to estimate the predictors of serum retinol and α-tocopherol concentration. There were no statistically significant differences in the average serum levels of retinol and α-tocopherol between overweight/obese and normal weight adult female subjects. Serum α- tocopherol concentrations were positively correlated with serum total cholesterol level (TChol) and body mass index (BMI), but inversely with total energy intake and past dieting behaviour. The TChol and total energy intake were identified as predictors of serum retinol levels. Intakes of fat and vitamin E and A, age, serum triglyceride concentration, smoking, alcohol consumption and physical activity were unrelated to serum levels of retinol or α-tocopherol. The main finding of this study is that obesity is not associated with decreased serum retinol and α-tocopherol levels. In addition, these results indicated that dietary intake of vitamin A and E are poor predictors for serum retinol or α-tocopherol concentrations. Serum levels of both these vitamins are primarily influenced by TChol, obesity, total energy intake and past dieting behaviour

Phosphoric Acid Invasion in High Temperature PEM Fuel Cell Gas Diffusion Layers

In this work, liquid phosphoric acid was injected into polymer electrolyte membrane fuel cell (PEMFC) gas diffusion layers (GDLs) to visualize the invasion patterns developed at breakthrough. Three-dimensional (3D) images of the GDLs were obtained through X-ray computed tomography, and equivalent pore networks were generated as the basis for pore network simulations using OpenPNM. Strong qualitative agreement was obtained between the simulated and experimentally observed liquid phosphoric acid invasion patterns, which provided validation for the numerical modeling. Different GDL materials were evaluated by examining the effects of a micro porous layer (MPL) and pore size distribution on the saturation and distribution of phosphoric acid. The MPL was shown to restrict liquid phosphoric acid from entering the carbon fiber substrate. The overall phosphoric acid saturation at breakthrough was found to decrease significantly for samples containing an MPL due to the smaller pore sizes. Further, the influence of cracks in an MPL on overall saturation at breakthrough was investigated. It was observed that a crack-free MPL provided a more effective physical barrier to restrict the undesired leaching of liquid phosphoric acid through the GDL

Synchrotron X-Ray radiography of vanadium redox flow batteries – Time and spatial resolved electrolyte flow in porous carbon electrodes

A porous carbon electrode fully saturated with electrolyte is one crucial aspect of vanadium redox flow battery efficiency. It determines the electrochemically active surface area, provides more active sites for the reaction during operation, and prevents local degradation due to inhomogeneities in electrolyte distribution. We investigate the electrolyte invasion and distribution at open-circuit potential in heat-treated carbon felt electrodes at varying compression ratios and flow field configurations, using synchrotron X-ray radiography. The quantitative analysis yields time-resolved saturation values of the injection and resolves local changes in saturation to detect areas of lower electrolyte accessibility. Compression ratios of 50% and above lead to a high electrode utilization with more than 97% saturation over the felt thickness. In contrast, carbon felts at 25% and 17% compression only reach 49% and 15% saturation near the flow fields. However, increasing the flow velocity after the injection causes the boundary area next to the flow field to fill even at low compressions. This area is especially critical for the electrode utilization since it is invaded after the bulk. Depending on the compression level, it does not reach full saturation

Revealing the Multifaceted Impacts of Electrode Modifications for Vanadium Redox Flow Battery Electrodes

Carbon electrodes are one of the key components of vanadium redox flow batteries (VRFBs), and their wetting behavior, electrochemical performance, and tendency to side reactions are crucial for cell efficiency. Herein, we demonstrate three different types of electrode modifications: poly(o-toluidine) (POT), Vulcan XC 72R, and an iron-doped carbon–nitrogen base material (Fe–N–C + carbon nanotube (CNT)). By combining synchrotron X-ray imaging with traditional characterization approaches, we give thorough insights into changes caused by each modification in terms of the electrochemical performance in both half-cell reactions, wettability and permeability, and tendency toward the hydrogen evolution side reaction. The limiting performance of POT and Vulcan XC 72R could mainly be ascribed to hindered electrolyte transport through the electrode. Fe–N–C + CNT displayed promising potential in the positive half-cell with improved electrochemical performance and wetting behavior but catalyzed the hydrogen evolution side reaction in the negative half-cell

Pore Network Modeling of Compressed Fuel Cell Components with OpenPNM

Pore network modeling is used to model water invasion and multiphase transport through compressed PEFC gas diffusion layers. Networks are created using a Delaunay tessellation of randomly placed base-points setting the pore locations and its compliment, the Voronoi diagram, is used to define the location of fibers and resultant pore and throat geometry. The model is validated in comparison to experimental capillary pressure curves obtained on compressed and uncompressed materials. Primary drainage is simulated with an invasion percolation algorithm that sequentially invades pores and throats separately with excellent agreement to experimental data, but required a slight modification to account for the higher aspect ratio of compressed pores. Compression is simulated by scaling the through-plane coordinates in a uniform manner representing a GDL wholly beneath the current-collector land. The relative permeability and diffusivity show some dependence on uniform compression. In-plane porosity variations introduced by land-channel compression are also investigated which have a marked effect on the limiting current. Saturation at breakthrough does not appear to be dependent on compression. However, a more important parameter, namely the peak saturation, is shown to influence the fuel cell performance and is dependent on the percolation inlet conditions

OpenPNM: A Pore Network Modeling Package

Pore network modeling is a widely used technique for simulating multiphase transport in porous materials, but there are very few software options available. This work outlines the OpenPNM package that was jointly developed by several porous media research groups to help address this gap. OpenPNM is written in Python using NumPy and SciPy for most mathematical operations, thus combining Python's ease of use with the performance necessary to perform large simulations. The package assists the user with managing and interacting with all the topological, geometrical, and thermophysical data. It also includes a suite of commonly used algorithms for simulating percolation and performing transport calculations on pore networks. Most importantly, it was designed to be highly flexible to suit any application and be easily customized to include user-specified pore-scale physics models. The framework is fast, powerful, and concise. An illustrative example is included that determines the effective diffusivity through a partially water-saturated porous material with just 29 lines of code