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To understand the fluid temperature and pressure during the Ouachita orogeny, we used isotopic analysis of syntectonic veins and adjacent host material, quartz-calcite oxygen isotope thermometry and fluid inclusion analysis. The veins were at or near isotopic equilibrium with their host rocks; neither the host nor veins has been isotopically reset. The average isotopic variation in (delta18)O between vein and host is 2.4 plus/minus 1.7% and 0.7 plus/minus 1.7% for quartz and calcite, respectively. The temperature of vein formation from quartz-calcite oxygen isotope thermometry is about 210-430 degrees C. Although this is a large range, the temperature does not vary systematically in the exposed Ordovician through Mississippian rocks. The lack of isotopic difference between host and vein suggests that the host oxygen determined that of the veins. This in turn suggests that the fluid in the rocks did not change regionally. The vitrinite reflectance/temperature of the host rocks increases with restored stratigraphic depth more than that calculated with the quartz-calcite thermometer in veins. Fluid inclusion analysis in vein quartz constrains homogenization temperatures to be from 106-285 degrees C. Isochores from fluid inclusion analyses were constrained using quartz-calcite thermometry and vitrinite reflectance temperatures to calculate vein formation pressures of 0.3?4.7 kbars. These pressures correspond to vein formation depths up to 19 km, assuming an unduplicated stratigraphic section. Using burial curves and a reasonable range of geothermal gradients, vein formation ages are between 300 to 315 Ma, i.e., Early to Middle Pennsylvanian.

Kosowski, Timmermann, Wermers, and White (2006) find that certain growth-oriented fund managers have substantial skill but do not stipulate the particular skills that they possess. I use novel style timing models to examine in detail the timing skills of 3,181 US equity mutual funds classified as having a growth investment objective by Standard & Poor’s, over the period from 1993 to 2006. To control for idiosyncratic variation in mutual fund returns, the bootstrap method of Kosowski et al. is used to analyze the significance of alpha and timing coefficient estimates. To exclude the possibility that the observed timing ability is due to good luck, synthetic funds are examined as in Busse (1999). The results indicate that growth-oriented fund managers who earn abnormal returns demonstrate substantial growth timing skill, i.e. successful timing activity across the value/growth continuum. This observed growth timing ability accounts for at least 45% of abnormal returns and is persistent; the top 10% of funds which demonstrate growth timing ability in the past three years also demonstrate the best growth timing ability in the following year. Successful growth timing is confined to those managers who invest primarily in growth stocks. However, there is little evidence of successful market timing (i.e. forecasting future market states and weighting equity exposure accordingly), size timing (i.e. adjusting exposure between small and large capitalization stocks) or momentum timing (i.e. switching between momentum investing and contrarian investing strategies). The models employed clearly distinguish between growth timing and market timing skills, thereby avoiding a common misidentification problem.

Symbol timing recovery is an important function of any digital receiver. In the wireless mobile data field the task of establishing accurate symbol timing at the receiver is complicated by the time varying channel. This time varying channel also makes the use of coherent modulation schemes significantly more difficult. This is one of the major reasons that almost all existing mobile wireless digital standards utilise some form of differential modulation and detection. This thesis takes a primarily practical approach to the investigation of timing and phase estimation problems. The main focus of the work is on the comparison of three existing all digital timing synchronisation algorithms, two of which were originally designed for the AWGN channel, and the third was designed from ML principles for the Rayleigh fading channel. In order to test these sub-systems in the wider context of receiver performance, a pilot symbol assisted (PSAM) receiver was simulated to compare the effects of the different synchronisers on receiver steady state performance. Finally, because the real time implementation aspects of software radio are of considerable interest to the author, some attempt has been made to migrate the MATLAB synchronisation simulations to a real time DSP platform, specifically the TMS320C6701 Texas Instruments floating point device.

The present study adopted Articulatory Phonology as a theoretical framework to investigate the aticulatory timing of English consonant clusters. Both native and non-native (Mandarin ESL learners) speakers’ performances were of interest. An acoustic approach was taken to explore the consonantal overlap in both native and non-native English speakers’ production. Also investigated in the present study were the factors that influence the overlap between consonants. Thirty-one native Mandarin speakers and eight native Canadian English speakers participated in the study. The thirty-one native Mandarin speakers were divided into three proficiency groups according to a pretest which evaluated Mandarin speakers’ English speaking proficiency. The experiment of the study was a reading task. Participants were instructed to put the words ending with the target consonant clusters in four carrier sentences and read them aloud. In total, 256 tokens (20 clusters×2 vowel environments×4 carrier sentences+12 consonants×2 vowel environments×4 carrier sentences) were recorded for each participant. The duration of each segment in the word was measured in the phonetic software, Praat. Three timing ratios: consonant to cluster, cluster to a pair of individual consonants, and cluster to rime were calculated. Repeated measures ANOVAs showed significant effect for place of articulation and manner of articulation on the articulatory timing of English consonant clusters in the coda position. Meanwhile, voicing feature, as an unexpected factor, was also reported to be an influential factor. More detailed analysis revealed that heterorganic clusters have more overlap than homorganic clusters. Within heterorganic clusters, a tongue tip consonant is more overlapped by a following tongue body consonant than a tongue body consonant is by a following tongue tip consonant. For manner of articulation, stops are found to be more overlapped by a following stop than by a following fricative. Overlapping caused by voicing feature was an unexpected outcome found in the present study. Voiceless consonant clusters have more overlap than voiced clusters. The difference between native and non-native speakers is also of interest. With respect to the amount of overlap, native speakers have more overlap than non-native speakers. Moreover, statistic tests reported a significant effect for proficiency group. From the comparison of mean values of three ratios, the performance of advanced group was close to native speakers. And intermediate and low groups exhibited similar performance. / Graduate

This study examined the DNA replication timing patterns of endothelial cell (EC)-enriched genes. We especially focused on a unique set of EC-enriched mRNA transcripts that possess differentially methylated regions (DMRs) within proximal promoters. It was previously shown that this DNA methylation plays an important functional role in regulating EC-enriched patterns of gene expression. Since the maintenance of these silencing marks is necessary for the inheritance of cell identity, the cell should ensure the proper transmission of such marks during mitotic cell cycle. Here we show that EC-enriched genes with DMRs replicate early during S phase in both expressing and non-expressing cell types. EC-enriched genes that do not have DMRs followed the expected trend, being early replicating in expressing cell types and late in non-expressing cell types. The relationship between DNA replication and DNA methylation was also investigated. A delay between DNA replication and DNA methylation was observed.

This study examined the DNA replication timing patterns of endothelial cell (EC)-enriched genes. We especially focused on a unique set of EC-enriched mRNA transcripts that possess differentially methylated regions (DMRs) within proximal promoters. It was previously shown that this DNA methylation plays an important functional role in regulating EC-enriched patterns of gene expression. Since the maintenance of these silencing marks is necessary for the inheritance of cell identity, the cell should ensure the proper transmission of such marks during mitotic cell cycle. Here we show that EC-enriched genes with DMRs replicate early during S phase in both expressing and non-expressing cell types. EC-enriched genes that do not have DMRs followed the expected trend, being early replicating in expressing cell types and late in non-expressing cell types. The relationship between DNA replication and DNA methylation was also investigated. A delay between DNA replication and DNA methylation was observed.

The rapid evolution of current and upcoming high speed and complex communications networks often necessitates flawless time synchronization among the network nodes in order to guarantee performance. GPS based synchronizers have long been used for synchronizing telecommunications equipment, currently providing an accuracy of up to 10ns. Such high accuracy demands excellent operation from GPS timing receivers. Interference is an important threat to GPS performance. Any degradation in performance, due to the introduction of interference, can cause these receivers to provide a low quality timing solution, or to lose lock with incoming GPS signals altogether. This consideration motivates the study of the performance of GPS timing receivers in the presence of harmful interference. This work is devoted to the theoretical and practical investigations of the effects of RF interference on GPS-based synchronizers and their impacts on communications networks. Contributions made during this work include: a) Identification of the processes and the parameters involved in producing a timing solution which are vulnerable to interference; b) experimentbased confirmation of a hypothesis about the effects of interference on GPS timing receivers; c) identification of the effects of degraded synchronization on the performance of communications networks, especially CDMA and GSM cellular networks, which rely upon GPS based synchronizers; and d) proposal of a method to predict and avoid communications network performance degradation.

Thesis (M.Eng.). / Written for the Dept. of Electrical & Computer Engineering. Title from title page of PDF (viewed 2008/05/13). Includes bibliographical references.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2008. / Includes bibliographical references (p. 59-63). Also available in electronic version.