26 research outputs found
Determination of TL Kinetic parameters of a phosphor
Present paper reports the methods of evaluating the kinetic parameters like trap depth, frequency factor etc. by using the Glow Curve of a phosphor. Peak shape method is found to be suitable amongst all reported methods. This method provides the nearest possible values of all studied kinetic parameters which are discussed in details. MS -Excel sheet is prepared for calculation
TL glow curve and kinetic of gamma irradiated quartz collected from Rasmada mines of C.G. basin
Present paper reports the TL glow curve and kinetic parameter of Quartz. The sample of natural quartz collected from Rasmada mines of C.G. basin is irradiated with gamma source. For gamma exposure Co60 gamma source was used and the exposure of 1 hour to 4 hour was given to the sample with dose 0.5kGy to 2 kGy. TL glow for quartz crystal shows the peaks at temperature 242, 256, 250 and 2520C for doses 2kGy to 0.5 kGy respectively. The powder sample shows TL glow peak at 236, 251, 254 and 2530C respectively. The corresponding activation energy and frequency factor is calculated by peak shape method. The activation energy found to be 0.79 eV for powder and 1.26 eV for quartz crystal, frequency factor is found to be 4X108 to 3X1013sec-1. The maximum activation energy is found for quartz crystal with gamma exposure of 2kGy. The sample shows first and second order kinetics. The sample was characterized by XRD. The Induction coupled plasma activated emission spectra (ICP - AES) analysis was done to find out the percentage of elements in the quartz mineral
Investigating the Ikaros family of transcription factors within macrophages in inflammatory bowel disease
The Ikaros Family of transcription factors Aiolos, Eos, Helios, Ikaros and Pegasus are a family of zinc finger proteins involved in the regulation of genes within a plethora of immune cells. Studies have suggested the family play a role in mediating Regulatory T cell (Treg) and T helper 17 (Th17) responses within Inflammatory Bowel Disease (IBD) but much of the detail of their function and expression is undocumented. This thesis examines the expression and roles of the family in IBD and the associated autoimmune liver disease Primary Sclerosing Cholangitis (PSC). Using qPCR and immunohistochemistry, we investigated the expression of the Ikaros family in blood derived CD4+ T Cells, myeloid cells, and whole bowel and liver tissue from diseased and healthy individuals. I also used an siRNA knockdown of Eos (siEos) within THP- 1 derived macrophages to investigate changes in phenotype and function. We report altered expression of family members within diseased bowel and liver in CD4+ T cells, but also myeloid cells. This includes previously unreported expression of the family within macrophage populations, with changes observed in macrophage subtypes. Ikaros family members were present in both the bowel and liver with greater numbers of Eos and Helios-expressing macrophages found in diseased bowel. Importantly, Eos expression was elevated in monocytes from both Biologic Naïve and anti-TNFalpha treated patient samples in comparison to Control, with novel correlations between Ikaros family members and liver clinical markers also identified. Using siRNA, we found siEos macrophages have reduced phagocytic capacity and upregulated proinflammatory mediator production suggesting Eos promotes a regulatory macrophage phenotype. Together, our results suggest a novel role for the Ikaros family within macrophage phenotype in bowel and liver disease
Minding the Gap: Understanding the Experiences of Racialized/Minoritized Bodies in Special Education
The issue of special education in the United States has been a contentious issue, at best, for the past 40 years. In Ontario, to a lesser extent, there have been issues of equal access to education for minoritized and racialized students. Special education in the Toronto area has not been without its issues surrounding parental advocacy, the use of assessments, and disproportionate number of English Language Learners in special education. This project examines how racialized and minoritized families understand special education practices and policies, specifically within the Toronto, York, Peel, and Halton Regions. The investigation is informed by nine interviews with students in grades 7 to 12, their respective mothers, and five special education administrators and educators. Students and parents identified themselves as Black, Latino/a, and South Asian. Within these categories, parents identified themselves as Somali, Trinidadian, Jamaican, and Punjabi-Sikh. Students were identified with a range of disabilities including learning, behavioural, and/or intellectual.
This research focuses on ways to interrogate and examine the experiences of minoritized students and their parents by bringing forward otherwise silenced voices and understanding what it means to “speak out” against the process of identification and placement in special education.
The findings of this investigation suggest a disconnect how policies and practices are implemented, and how, parents’ rights are understood. In particular, policies are inconsistently applied and are subject to the interpretation of educators and administrators, especially in relation to parental involvement and how much information should be released to families. The issue of language acquisition being read as a disability was also a noted concern. This investigation points to implications for teacher education programs, gaps in parental advocacy and notions of parental participation within schools, and re-examining special education assessments, practices, and policies.Ph
Antisense-mediated myostatin downregulation by destructive exon skipping using 2'O-methyl RNA and morpholino oligomers in skeletal muscle cells and animal products
Myostatin is a negative regulator of muscle mass, and several strategies are being developed to knock down the expression of the myostatin gene as a means to bring about improvements in muscle wasting conditions, including Duchenne muscular dystrophy (DMD). Improved muscle regeneration in the absence of myostatin has been demonstrated in mdx mice by-crossing them with myostatin null mice. Increased muscle strength and improved dystrophic pathophysiology has been found in the mdx mice treated with myostatin antibodies, purified myostatin propeptide (natural binding partner of myostatin) with a mouse fusion protein and AA V -mediated transfer of propeptide. Virus-based strategies have the major drawbacks of uncontrolled insertion into the target genome and undesirable immune response; whereas, injecting binding partners to the target-tissue might have low sustainability over a longer period of time. In this study the design and use of anti sense oligonucleotides (AOs) to manipulate myostatin pre-mRNA splicing and knockdown myostatin has been described. AOs of both 2'O-methyl RNA (2'OMePS-with a phosphorothioate backbone) and phosphorodiarnidate morpholino (PMO) chemistries were designed using different bioinformatics algorithms. Efficiency of destructive myostatin exon skipping was then demonstrated and evaluated comparatively by oligomer transfection of cultured muscle cells, and RT-PCR and bioactivity analyses. Sustained and high levels of destructive exon skipping of the myostatin mRNA, and increases in skeletal muscle mass and fibre sizes was observed up toi months following a single injection of Vivo-PMO (PMO conjugated to a cell-penetrating octa-guanidine moiety) into the tibialis anterior muscle in normal mice. The efficiency of Vivo-PMO was also compared to a PMO conjugated to a cell penetrating peptide moiety (B-PMO) by single intra -muscular treatment of wild type mice. Weekly intravenous injections of Vivo- PMO in normal mice also lead to myostatin exon skipping in selected skeletal muscles, and associated increases in tissue mass, cross-sectional area, and average fibre diameter. Dual exon skipping of myostatin and dystrophin was also carried out successfully in mdx mice. These studies indicate that (i) anti sense-mediated destructive exon skipping can be induced in the myostatin RNA, (ii) anti sense AO treatment reduces myostatin bioactivity and enhances muscle mass in vivo, and (iii) AO-induced myostatin exon- skipping may be a potential therapeutic strategy to counter muscular dystrophy, muscular atrophy, cachexia and sarcopenia.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Effect of Eu3+ Concentration on Luminescence Studies of Y4Al2O9 Phosphor
The present paper reports the effect of europium concentration on photoluminescence (PL) and thermoluminescence (TL) studies of Eu3+ doped Y4Al2O9 phosphor using inorganic materials like yttrium oxide (Y2O3), aluminium oxide (Al2O3), boric acid (H3BO3) as a flux, and europium oxide (Eu2O3). The sample was prepared by the modified solid state reaction method, which is the most suitable for large-scale production. The prepared phosphor sample was characterized using X-ray diffraction (XRD), field emission gun scanning electron microscopy (FEGSEM), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL), thermoluminescence (TL), and CIE techniques. The PL emission was observed in the range of 467, 535, 591, 611, 625, and 629 nm for the Y4Al2O9 phosphor doped with Eu3+ (0.1 mol% to 2.5 mol%). Excitation spectrum was found at 237 and 268 nm. Sharp peaks were found around 591, 611, and 625 nm with high intensity. From the XRD data, using Scherer’s formula, the calculated average crystallite size of Eu3+ doped Y4Al2O9 the phosphor is around 55 nm. Thermoluminescence study was carried out for the phosphor with UV irradiation. The present phosphor can act as single host for red light emission in display devices
Porcupine gnaw marks on a Late Pliocene bone from the Upper Siwaliks exposed near Village Khetpurali (Haryana, India)
Abstract Abstract:Bone accumulation by porcupines at archaeological sites is well known. However, in paleontological sites such a taphonomical occurrence is rather rare. We here report porcupine (Hystrix sp.) gnaw marks on an unidentified bone fragment, dated to ~2.6 Ma from the Upper Siwalik deposits exposed near Khetpurali (Haryana), India. The present gnaw marks are very distinct and are characterized by visible edges and grooves making clear broad and shallow furrows. The present find adds to our knowledge of Siwalik vertebrate taphonomy where most of the accumulations reported earlier were either fluvial or made by carnivores