Somatic embryogenesis can provide researchers with an important tool to study the physiological and molecular mechanisms involved in embryo development. In spruce, few lines are able to produce fully developed embryos due to the presence of malformed meristems. Genes from two families known as KNOX (knotted-like homeobox) and ARGONAUTE (AGO) have previously been found to be involved in meristem development and maintenance. This work documents the discovery of a new member of the AGO family of proteins designated as PgAGO and the further study of a KNOX gene known as HBK2. The complete coding sequence of both PgAGO and HBK2 was obtained through screening of cDNA libraries generated from white spruce (Picea glauca) somatic embryos. RNA in-situ hybridization studies showed that PgAGO mRNAs accumulate preferentially within cells of the shoot and root apical meristems in developing spruce embryos. In addition, the expression of PgAGO was low in white spruce lines unable to produce embryos in culture. Norway spruce (Picea abies) embryogenic tissue was transformed via microprojectile bombardment with an antisense construct of PgAGO. Down-regulation of PgAGO altered proper development of the apical meristems and reduced embryo regeneration. RNA in-situ hybridization studies showed that HBK2 is specifically expressed in the sub-apical and cortical regions of developing embryos. Like PgAGO, HBK2 expression was diminished in white spruce lines unable to produce embryos in culture. Transformation experiments with antisense constructs of HBK2 completely arrested somatic embryo development. This study reveals the importance of a functional meristem during embryo development. / October 2006

An in vitro technique was adapted for screening the ability of Rosa hybrida L. genotypes to form embryogenic callus to elucidate the inheritance of this ability. Filament and leaf petiole explants of modern rose cultivars 'Tournament of Roses' and 'Baby Love' were cultured on somatic embryogenesis induction media and evaluated for the ability to produce embryogenic callus. Cultures of 'Tournament of Roses' produced somatic embryos at a much higher frequency versus 'Baby Love' that produced no embryos. Subsequently, filament explants of eleven 'Tournament of Roses' x 'Baby Love' progeny genotypes were cultured on somatic embryogenesis induction media and evaluated for the ability to undergo somatic embryogenesis. The progeny genotypes produced somatic embryos at varied frequencies. The results obtained indicated that the ability to undergo embryogenesis in Rosa hybrida L. is heritable in an additive fashion with the involvement of more than one gene.

Somatic embryogenesis can provide researchers with an important tool to study the physiological and molecular mechanisms involved in embryo development. In spruce, few lines are able to produce fully developed embryos due to the presence of malformed meristems. Genes from two families known as KNOX (knotted-like homeobox) and ARGONAUTE (AGO) have previously been found to be involved in meristem development and maintenance. This work documents the discovery of a new member of the AGO family of proteins designated as PgAGO and the further study of a KNOX gene known as HBK2. The complete coding sequence of both PgAGO and HBK2 was obtained through screening of cDNA libraries generated from white spruce (Picea glauca) somatic embryos. RNA in-situ hybridization studies showed that PgAGO mRNAs accumulate preferentially within cells of the shoot and root apical meristems in developing spruce embryos. In addition, the expression of PgAGO was low in white spruce lines unable to produce embryos in culture. Norway spruce (Picea abies) embryogenic tissue was transformed via microprojectile bombardment with an antisense construct of PgAGO. Down-regulation of PgAGO altered proper development of the apical meristems and reduced embryo regeneration. RNA in-situ hybridization studies showed that HBK2 is specifically expressed in the sub-apical and cortical regions of developing embryos. Like PgAGO, HBK2 expression was diminished in white spruce lines unable to produce embryos in culture. Transformation experiments with antisense constructs of HBK2 completely arrested somatic embryo development. This study reveals the importance of a functional meristem during embryo development.

Micropropagation was investigated in order to develop protocols for rapid mass production of shoots ofSorbus aucuparia and Alnus glutinosa. Removal of apical dominance either physically by pruning the plantlets or chemically by using anti-auxins TIB A (2,3,5-triiodobenzoic acid) and NPA (1-naphthylphthalamic acid) was investigated. There was a 6-fold increase in the number of rooting-ready shoots of S. aucuparia produced by the pruning of plantlets grown in vitro. A. glutinosa however, needed more drastic measures to remove apical dominance and block the endogenous auxin transport. Incorporation of TIBA (3 μm) in the medium produced an initial 8- fold increase in the number of shoots. However, repeated subculture of shoots of Alnus on TIBA containing medium proved detrimental to shoot multiplication. There was 100% rooting of shoots of S. aucuparia on agar solidified medium. The auxin: cytokinin ratio of the multiplication medium played an important role in the rooting ability of shoots. A. glutinosa also had 100% rooting on agar solidified medium. Plants were acclimatised in Baumgartner vessels before transferring to soil. There was 100% rooting and survival of the shoots of A. glutinosa both after transfer to Baumgartner vessels and subsequent transfer to soil. In S. aucuparia the survival rates in Baumgartner vessels was 70% and after transfer to soil was 65%. Direct somatic embryogenesis from zygotic tissue of both S. aucuparia and A. glutinosa was achieved. Embryos of S. aucuparia were produced on medium containing MS salts and vitamins supplemented with 1 μM BAP, 1 μM kinetin, 0.5 μM NAA, 250 mg/L L-glutamine and 500 mg/L casein hydrolysate. A. glutinosa embryos were obtained on medium containing salts and vitamins of Driver and Kuniyuki (1984) supplemented with 3 μM BAP. No auxin was required. Adventitous shoot regeneration from leaves of S.aucuparia was also achieved at a frequency of 40% on medium containing MS salts and vitamins supplemented with 10 μM TDZ and 1 μM NAA. A method for chromosome doubling of S. aucuparia using 15 uM pronamide to treat shoot tips immersed in a semi-solid medium was developed. After 14 days of treatment, 86.5% treated shoots survived and there was 44.5% chromosome doubling of the survivors. The tetraploid shoot had a higher rate of multiplication than the diploid shoots. The involvement of extracellular proteins in direct somatic embryogenesis of Prunus 'Colt' was studied. Changes in the expression of proteins were observed from the first day of transferring the tissue to embryo induction medium. Most changes were seen on the days 28 and 35 when the embryos became visible.

Somatic embryogenesis can provide researchers with an important tool to study the physiological and molecular mechanisms involved in embryo development. In spruce, few lines are able to produce fully developed embryos due to the presence of malformed meristems. Genes from two families known as KNOX (knotted-like homeobox) and ARGONAUTE (AGO) have previously been found to be involved in meristem development and maintenance. This work documents the discovery of a new member of the AGO family of proteins designated as PgAGO and the further study of a KNOX gene known as HBK2. The complete coding sequence of both PgAGO and HBK2 was obtained through screening of cDNA libraries generated from white spruce (Picea glauca) somatic embryos. RNA in-situ hybridization studies showed that PgAGO mRNAs accumulate preferentially within cells of the shoot and root apical meristems in developing spruce embryos. In addition, the expression of PgAGO was low in white spruce lines unable to produce embryos in culture. Norway spruce (Picea abies) embryogenic tissue was transformed via microprojectile bombardment with an antisense construct of PgAGO. Down-regulation of PgAGO altered proper development of the apical meristems and reduced embryo regeneration. RNA in-situ hybridization studies showed that HBK2 is specifically expressed in the sub-apical and cortical regions of developing embryos. Like PgAGO, HBK2 expression was diminished in white spruce lines unable to produce embryos in culture. Transformation experiments with antisense constructs of HBK2 completely arrested somatic embryo development. This study reveals the importance of a functional meristem during embryo development.

Thesis (Ph. D.)--Carleton University, 1992. / Also available in electronic format on the Internet.

Mindfulness meditation has received increased attention from clinicians and researchers alike in recent decades and subsequently has been incorporated into treatments for a variety of psychological conditions, including anxiety. Although a small body of experimental research examining the influence of mindfulness on anxiety has developed, few studies to date have experimentally tested the effects of mindfulness meditations beyond a brief breathing meditation. This gap in the literature restricts our understanding of the efficacy of various brief mindfulness interventions currently utilized as clinical tools for anxiety. Therefore, the aim of the current study was to expand upon previous studies by examining the differential effect of two mindfulness exercises – a mindful body scan and a breathing meditation. More specifically, the current project investigated the influence of each intervention on 1) state mindfulness, 2) state cognitive anxiety, and 3) state somatic anxiety. Further, the project examined the moderating influence of participants’ reactions and compliance to each condition on pre-to-post intervention changes in cognitive and somatic anxiety. The current study suggests that brief mindfulness tasks induced state decentering, but not curiosity. However, there appears to be relative uniformity in the effect of both interventions on cognitive and somatic anxiety. Finally, the current study indicates that enjoyment while completing a mindfulness exercise is an important moderating factor on the efficacy of mindfulness interventions for anxiety.

Throughout history, professional musicians experience pain when singing or playing instruments (Fishbein et al., 1988). Research continues to indicate pain remains a problem amongst musicians. Musicians looking to solve performance-related pain have used a variety of solutions including somatic, or movement, study. One method of movement study, the only one specifically dedicated to musicians, is Body Mapping. In this qualitative study I used an Interpretative Phenomenological Analysis design to explore the experiences of beginning string students using lessons infused with Body Mapping (BMg) principles and students utilizing a more traditional method. The purpose of the study was to understand the ways in which lessons based on BMg principles might affect students’ lived experiences as they began to play a string instrument (violin, viola, cello), as opposed to those students whose lessons were more traditional, based on published beginning method books. Two teachers and four sixth-grade beginning string classes at two schools participated in this study. Eleven students were selected for in-depth interviews about their experiences in beginning string class. The teachers utilized a traditional string method book Essential Elements for Strings 2000 (Gillespie, 2000) with both of their classes, but also incorporated a researcher-designed curriculum incorporating BMg principles with one of the classes. The researcher collected qualitative data through interviews and observations. Journals, completed by all students, provided both qualitative and quantitative data. Both journal and chi square data indicated that students in the BMg classes felt the BMg lessons were helpful to learn about their body in movement. Qualitative data showed students retained and used anatomical words presented in the BMg lessons while the qualitative interviews of BMg students expressed greater awareness of how their bodies worked than students in the traditional classes. Teachers found the BMg principles to positively impact their classroom environments and student responses. The BMg curriculum aided study participants in finding a common language with which to communicate about the body. Analysis of study participants’ lived experiences indicated that BMg made a positive difference in the early learning of string instruments. Results of this study suggest that it is important that a curriculum using BMg principles be further explored and implemented widely among string teachers as a means to prevent performance related pain and injury.

Health outcomes following a traumatic event are an important aspect of recovery from any type of trauma. Further, distress and psychopathology, specifically Posttraumatic Stress Disorder (PTSD), have been shown to have a significant impact on physical health recovery post-trauma. The current study utilized a sample of 56 (48 women, 8 men) residential fire survivors to examine the potential mediating effect of PTSD and PTSD symptom subclusters. Participants were interviewed four months after a residential fire and were assessed on levels of exposure to the fire (Fire Questionnaire & Resource Loss Scale), PTSD symptomology (Anxiety Disorder Interview Schedule), and somatic health complaints (Brief Symptom Inventory). Consistent with previous findings, PTSD was found to mediate the relationship between exposure to a traumatic event and reporting of health symptoms. Further, the increased arousal subcluster was found to mediate the aforementioned relationship; the avoidance symptom subcluster was found to partially mediate the same relationship. Implications of results of the current project are discussed with regard to the impact of trauma on survivorsâ health, along with recommendations for further research. / Master of Science

It is important to understand the entire spectrum of somatic variants to gain more insight into mutations that occur in different cancers for development of better diagnostic, prognostic and therapeutic tools. This thesis outlines our work in understanding somatic variant calling, improving the identification of somatic variants from whole genome and whole exome platforms and identification of biomarkers for lung cancer. Integrating somatic variants from whole genome and whole exome platforms poses a challenge as variants identified in the exonic regions of the whole genome platform may not be identified on the whole exome platform and vice-versa. Taking a simple union or intersection of the somatic variants from both platforms would lead to inclusion of many false positives (through union) and exclusion of many true variants (through intersection). We develop the first framework to improve the identification of somatic variants on whole genome and exome platforms using a machine learning approach by combining the results from two popular somatic variant callers. Testing on simulated and real data sets shows that our framework identifies variants more accurately than using only one somatic variant caller or using variants from only one platform. Short tandem repeats (STRs) are repetitive units of 2-6 nucleotides. STRs make up approximately 1% of the human genome and have been traditionally used as genetic markers in population studies. We conduct a series of in silico analyses using the exome data of 32 individuals with lung cancer to identify 103 STRs that could potentially serve as cancer diagnostic markers and 624 STRs that could potentially serve as cancer predisposition markers. Overall these studies improve the accuracy in identification of somatic variants and highlight the association of STRs to lung cancer. / Ph. D.