Analysis Of The A11a22 X 11a11 And A 33a22 X 1 electronic transitions in selenocarbonyl difluoride

The absorption spectrum of F2CSe in the 18800-21900 cm-1 region has been recorded at -770 C and 220 C under the conditions of medium resolution. The responsible electronic promotion is TI* + n excitation which leads to 3A2 and lA2 excited states. Progressions in vI', v2', v3" v4' and v4" have been identified in the spectrum and have been analyzed in terms of vibronic transitions between a planar ground state and a nQnplanar excited state. The - 3 - 1 - 1 - 1 origins of the a A2 + X Al and A A2 + X Al systems were assigned to the bands at 19018 cm-l and 19689 cm-l . This has given a singlet-triplet splittl. n g lA2 - 3A2 P f 671 cm -1 The out-of-plane wagging levels were found to be anharmonic. 1 -1 Barrier heights of 2483 cm- and 2923 cm were obtained for the lA2 and 3A2 upper states from a fitting of the energy levels of a Lorentzian-quadratic function to the observed levels in the out-of-plane wagging modes. 1 3 For the A2 and A2 states nonplanar equilibrium angles of 30.10 and 31.40 have been evaluated respectively. i

Effects of large anphiphilic ligands upon the spectra and kinetics of cytochrome C oxidase

Cytoch ro me c oxidase (ferrocytochrome c : 02 oxidoreductase ; EC 1.9. 3.1) is the terminal enzyme in the mitochondrial electron transport chain, catalyzing the transfer of electrons from ferrocytochrome c to molecular oxygen. The effects of two large amphiphilic molecules - valinomycin and dibucaine upon the spectra of the isolated enzyme and upon the activity of both isolated enzyme and enzyme in membrane systems are investigated by using spectrophotometric and oxygen electrode techniques. The results show that both valinomycin and dibucaine change the Soret region of the speetrum and cause a partial inhibition in a concentration range higher than that in which they act as ionophores. It is concluded that both valinomycin and dibucaine binding induce a conformational change of the protein structure which modifies the spectrum of the a3 CUB centre and diminishes the rate of electron transfer between cytochrome a and the binuclear centre.

An Examination of Youth Perceptions and Understandings of their Experiences with Extrajudicial Sanctions in Relation to Key Principles of the YCJA

It is unclear how the principles of meaningful consequences, fair and proportionate accountability, and rehabilitation and reintegration under the Youth Criminal Justice Act (2003) are understood and experienced by youth participating in diversion from youth court. Interviews with 20 youth revealed that, from their understanding, extrajudicial sanctions were viewed as accomplishing the goals of meaningful consequences and fair and proportionate accountability relatively well, but less emphasis was placed on rehabilitation and reintegration. The findings suggest that there may be a need an examination of the spectrum of responses available to youth under the umbrella of Extrajudicial Sanctions and their ability to achieve the key principles of the legislation. Implications for both youth and policy are addressed.

HUMAN GENOME VARIATIONS AND EVOLUTION WITH A FOCUS ON THE ANALYSIS OF TRANSPOSABLE ELEMENTS

Genome sequence varies in numerous ways among individuals although the gross architecture is fixed for all humans. Retrotransposons create one of the most abundant structural variants in the human genome and are divided in many families, with certain members in some families, e.g., L1, Alu, SVA, and HERV-K, remaining active for transposition. Along with other types of genomic variants, retrotransponson-derived variants contribute to the whole spectrum of genome variants in humans. With the advancement of sequencing techniques, many human genomes are being sequenced at the individual level, fueling the comparative research on these variants among individuals. In this thesis, the evolution and functional impact of structural variations is examined primarily focusing on retrotransposons in the context of human evolution. The thesis comprises of three different studies on the topics that are presented in three data chapters. First, the recent evolution of all human specific AluYb members, representing the second most active subfamily of Alus, was tracked to identify their source/master copy using a novel approach. All human-specific AluYb elements from the reference genome were extracted, aligned with one another to construct clusters of similar copies and each cluster was analyzed to generate the evolutionary relationship between the members of the cluster. The approach resulted in identification of one major driver copy of all human specific Yb8 and the source copy of the Yb9 lineage. Three new subfamilies within the AluYb family – Yb8a1, Yb10 and Yb11 were also identified, with Yb11 being the youngest and most polymorphic. Second, an attempt to construct a relation between transposable elements (TEs) and tandem repeats (TRs) was made at a genome-wide scale for the first time. Upon sequence comparison, positional cross-checking and other relevant analyses, it was observed that over 20% of all TRs are derived from TEs. This result established the first connection between these two types of repetitive elements, and extends our appreciation for the impact of TEs on genomes. Furthermore, only 6% of these TE-derived TRs follow the already postulated initiation and expansion mechanisms, suggesting that the others are likely to follow a yet-unidentified mechanism. Third, by taking a combination of multiple computational approaches involving all types of genetic variations published so far including transposable elements, the first whole genome sequence of the most recent common ancestor of all modern human populations that diverged into different populations around 125,000-100,000 years ago was constructed. The study shows that the current reference genome sequence is 8.89 million base pairs larger than our common ancestor’s genome, contributed by a whole spectrum of genetic mechanisms. The use of this ancestral reference genome to facilitate the analysis of personal genomes was demonstrated using an example genome and more insightful recent evolutionary analyses involving the Neanderthal genome. The three data chapters presented in this thesis conclude that the tandem repeats and transposable elements are not two entirely distinctly isolated elements as over 20% TRs are actually derived from TEs. Certain subfamilies of TEs themselves are still evolving with the generation of newer subfamilies. The evolutionary analyses of all TEs along with other genomic variants helped to construct the genome sequence of the most recent common ancestor to all modern human populations which provides a better alternative to human reference genome and can be a useful resource for the study of personal genomics, population genetics, human and primate evolution.

Indices and Implications of Emotional Underarousal for Persons with a History of Head Trauma

We examined the role of altered emotional functioning across the spectrum of injury severity (mild head injury [MHI], moderate/severe traumatic brain injury [TBI]), its implications for social behaviours, and the effect of modifying arousal and its relation to cognitive performance. In the first study (N = 230), students with self-reported MHI endorsed engaging in socially unacceptable and erratic behaviours significantly more often than did those with no MHI. We did not find significant differences between the groups in the measure of emotional intelligence (EI); however, for students who reported a MHI, scores on the EI measure significantly predicted reports of socially unacceptable behaviours such that lower scores predicted poorer social functioning, accounting for approximately 20% of the variance. Also, the experience of postconcussive symptoms was found to be significantly greater for students with MHI relative to their peers. In the second study (N = 85), we further examined emotional underarousal in terms of physiological (i.e., electrodermal activation [EDA]) and self-reported responsivity to emotionally-evocative picture stimuli. Although the valence ratings of the stimuli did not differ between students with and without MHI as we had expected, we found evidence of reduced and/or indiscriminate emotional responding to the stimuli for those with MHI which mimics that observed in other studies for persons with moderate/severe TBI. We also found that emotional underarousal followed a gradient of injury severity despite reporting a pattern of experiencing more life stressors. In the third study (N = 81), we replicated our findings of emotional underarousal for those with head trauma and also uniquely explored neuroendocrine aspects (salivary cortisol; cortisol awakening response [CAR]) and autonomic indices (EDA) of emotional dysregulation in terms of stress responsivity across the spectrum of injury severity (MHI [n = 32], moderate/severe TBI [n = 9], and age and education matched controls [n = 40]). Although the manipulation was effective in modifying arousal state in terms of autonomic and self-reported indices, we did not support our hypothesis that increased arousal would be related to improved performance on cognitive measures for those with prior injury. To our knowledge, this is the only study to examine the CAR with this population. Repeated measure analysis revealed that, upon awakening, students with no reported head trauma illustrated the typical CAR increase 45 minutes after waking, whereas, students who had a history of either mild head trauma or moderate/severe TBI demonstrated a blunted CAR. Thus, across the three studies we have provided evidence of emotional underarousal, its potential implications for social interactions, and also have identified potentially useful indices of dysregulated stress responsivity regardless of injury severity.

The Arabidopsis NPR1 Protein Is a Receptor for the Plant Defense Hormone Salicylic Acid

Systemic Acquired Resistance (SAR) is a type of plant systemic resistance occurring against a broad spectrum of pathogens. It can be activated in response to pathogen infection in the model plant Arabidopsis thaliana and many agriculturally important crops. Upon SAR activation, the infected plant undergoes transcriptional reprogramming, marked by the induction of a battery of defense genes, including Pathogenesis-related (PR) genes. Activation of the PR-1 gene serves as a molecular marker for the deployment of SAR. The accumulation of a defense hormone, salicylic acid (SA) is crucial for the infected plant to mount SAR. Increased cellular levels of SA lead to the downstream activation of the PR-1 gene, triggered by the combined action of the Non-expressor of Pathogenesis-related Gene 1 (NPR1) protein and the TGA II-clade transcription factor (namely TGA2). Despite the importance of SA, its receptor has remained elusive for decades. In this study, we demonstrated that in Arabidopsis the NPR1 protein is a receptor for SA. SA physically binds to the C-terminal transactivation domain of NPR1. The two cysteines (Cys521 and Cys529), which are important for NPR1’s coactivator function, within this transactivation domain are critical for the binding of SA to NPR1. The interaction between SA and NPR1 requires a transition metal, copper, as a cofactor. Our results also suggested a conformational change in NPR1 upon SA binding, releasing the C-terminal transactivation domain from the N-terminal autoinhibitory BTB/POZ domain. These results advance our understanding of the plant immune function, specifically related to the molecular mechanisms underlying SAR. The discovery of NPR1 as a SA receptor enables future chemical screening for small molecules that activate plant immune responses through their interaction with NPR1 or NPR1-like proteins in commercially important plants. This will help in identifying the next generation of non-biocidal pesticides.