236 research outputs found
Self-Mutilation in a Community Sample of Adolescents.
Get PDFThe purpose of this study was to examine the provisional prevalence rates and characteristics of self-mutilative behavior in a community sample of adolescents. A total of 368 adolescents between the ages of 12 and 19 participated in this investigation. Thirty-nine percent of high school students sampled (n = 143) engaged in self-mutilation within the past year. Commonly endorsed behaviors were biting self, hitting self on purpose, and cutting/carving skin. Self-mutilators were likely to engage in these behaviors to reduce internal tension, as well as to gain attention. Self-mutilators were compared with non-mutilating adolescents (n = 225) on self-report measures of negative self-evaluation, cognitive distortions, social problem-solving capabilities, and suicide ideation. Self-mutilators reported greater negative automatic thoughts and poorer self-worth than non-mutilators. Additionally, self-mutilators were more likely to have made a suicide attempt(s) in the past and reported higher levels of suicide ideation. In multivariate regression analyses, suicide ideation and history of suicide attempt(s) contributed to the prediction of self-mutilative behavior, correctly classifying 71% of the total sample. Clinical implications of the results are discussed in the context of contemporary teenage culture
Signaling Networks that Induce Melanomagenesis and Metastasis that can be Exploited for Therapeutic Benefit
Get PDFMelanoma is the most lethal type of skin cancer and originates in melanocytes, cells that produce the pigment melanin. Five year survival rates are particularly high for this type of cancer if the tumor is diagnosed and treated early. However, survival rates decline significantly if the tumor is allowed to metastasize. Frequency of melanoma has risen over recent years, especially in young people. Much progress has been made in treating melanoma; however, tumor recurrence is frequently seen in patients after treatment has concluded. The leading genes that are found to be mutated in melanoma are v-Raf murine sarcoma viral oncogene homolog B1 (BRAF), neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS), phosphatase and tensin homolog deleted on chromosome ten (PTEN) and cyclin dependent kinase inhibitor 2A (CDKN2A) which belong to the MAPK (Mitogen-activated protein kinase/Extracellular signal-regulated kinases) pathway, the phosphoinositide 3\u27 kinase (PI3K)/AKT pathway or the INK4/ARF locus. Together, these two pathways and locus form a signaling network that work in tandem to promote cell proliferation, migration, invasion and metastasis. Recent breakthroughs in treating melanoma include the advent of BRAF inhibitors, but patients often experience tumor recurrence. Research conducted to understand acquired BRAF inhibitor resistance suggests that tumor regrowth is due to continued activation of the MAPK and PI3K/AKT pathways through BRAF independent routes. Therefore, new treatments, which can be personalized, are being developed that target multiple components of both of these pathways. The epigenetic causes of melanoma are vast and are just recently becoming clear
Co-operative preservation activities in the UK: findings of a research project
Get PDFReports the findings of a BLRIC-funded research project, which set out to identify and evaluate current and recent co-operative preservation activities, and produce guidelines which will help librarians and archivists to engage in successful co-operative preservation activity
Measuring phonological distance between languages
Get PDFThree independent approaches to measuring cross-language phonological distance are pursued in this thesis: exploiting phonological typological parameters; measuring the cross-entropy of phonologically transcribed texts; and measuring the phonetic similarity of non-word nativisations by speakers from different language backgrounds. Firstly, a set of freely accessible online tools are presented to aid in establishing parametric values for syllable structure and phoneme inventory in different languages. The tools allow researchers to make differing analytical and observational choices and compare the results. These tools are applied to 16 languages, and correspondence between the resulting parameter values is used as a measure of phonological distance. Secondly, the computational technique of cross-entropy measurement is applied to texts from seven languages, transcribed in four different ways: a phonemic IPA transcription; with Elements; and with two sets of binary distinctive features in the SPE tradition. This technique results in consistently replicable rankings of phonological similarity for each transcription system. It is sensitive to differences in transcription systems. It can be used to probe the consequences for information transfer of the choices made in devising a representational system. Thirdly, participants from different language backgrounds are presented with non-words covering the vowel space, and asked to nativise them. The accent distance metric ACCDIST is applied to the resulting words. A profile of how each speaker’s productions cluster in the vowel space is produced, and ACCDIST measures the similarity of these profiles. Averaging across speakers with a shared native language produces a measure of similarity between language profiles. Each of these three approaches delivers a quantitative measure of phonological similarity between individual languages. They are each sensitive to different analytical choices, and require different types and quantities of input data, and so can complement each other. This thesis provides a proof-of-concept for methods which are both internally consistent and falsifiable
Visualizing genotype × phenotype relationships in the GAW15 simulated data
Get PDFWe have developed a graphical display tool called SIMLAPLOT for visualizing different ways in which continuous covariates may influence the genotype-specific risk for complex human diseases. The purpose of our study was to examine continuous covariates in the Genetic Analysis Workshop 15 simulated data set using our novel graphical display tool, with knowledge of the answers. The generated plots provide information about genetic models for the simulated continuous covariates and may help identify the single-nucleotide polymorphisms associated with the underlying quantitative trait loci
Two-stage study designs for analyzing disease-associated covariates: linkage thresholds and case-selection strategies
Get PDFThe incorporation of disease-associated covariates into studies aiming to identify susceptibility genes for complex human traits is a challenging problem. Accounting for such covariates in genetic linkage and association analyses may help reduce the genetic heterogeneity inherent in these complex phenotypes. For Genetic Analysis Workshop 15 (GAW15) Problem 3 simulated data, our goal was to compare the power of several two-stage study designs to identify rheumatoid arthritis-related genes on chromosome 9 (disease severity), 11 (IgM), and 18 (anti-cyclic citrinullated protein), with knowledge of the answers. Five study designs incorporating an initial linkage step, followed by a case-selection scheme and case-control association analysis by logistic regression, were considered. The linkage step was either qualitative-trait linkage analysis as implemented in MERLIN-nonparametric linkage (NPL), or quantitative-trait locus analysis as implemented in MERLIN-REGRESS. A set of cases representing either one case from each available family, one case per linked family (NPL ≥ 0), or one case from each family identified by ordered-subset analysis was chosen for comparison with the full set of 2000 simulated controls. As expected, the performance of these study designs depended on the disease model used to generate the data, especially the simulated allele frequency difference between cases and controls. The quantitative trait loci analysis performed well in identifying these loci, and the power to identify disease-associated alleles was increased by using ordered-subset analysis as a case selection tool
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