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Recent studies are beginning to show evidence of marital problems for couples that have engaged in early premarital sexual activity compared to those who do not. Adult attachment theory plays an important role in explaining many kinds of distress for couples and helps explain sexual interaction, thus, in this study it is posited that attachment may influence sexual timing patterns. This study focuses on the relationship between insecure attachment styles and early premarital sexual timing. The sample consisted of 256 couples who took the Relationship Evaluation (RELATE) to measure their attachment styles and sexual timing while controlling for length of relationship, religiosity, education and age, which may be related to sexual timing. Models were tested for males and females separately using structural equation modeling (SEM). Results showed a significant, positive relationship between female anxious attachment and early sexual timing. Results also showed a significant negative relationship between female avoidant attachment and early sexual timing. No results showed significant relationships between male insecure attachment and sexual timing. Implications for couples, clinicians and educators are discussed.

Over the past two centuries, anadromous alewife populations have drastically declined due to damming, inadequate fish passage, overfishing in the ocean and freshwater, climate change, and reduction in habitat quality. Alewife populations are currently assessed by counting adult fish as they migrate upstream, but little is known about resulting juvenile production within lakes. Lack of knowledge of freshwater life history characteristics of juvenile alewife limits our understanding of overall productivity. For this thesis, I fill existing information gaps by (1) characterizing the timing of adult alewife migrations and subsequent spawning (Chapter 2), and (2) assessing juvenile alewife density, size, growth, and mortality within lakes, and abiotic factors influencing these estimates across lakes (Chapter 3). Twenty lakes across coastal Massachusetts were sampled for juvenile alewife and water quality in summer 2014. Each lake was sampled three times: Round 1 (29 May to 15 June), Round 2 (26 June to 16 July), and Round 3 (27 July to 15 August). Analyses of instream adult counts and otolith-based estimates of spawning date from captured juveniles showed a distinct delay (7-28 d) between the beginning of the adult migration run and spawning, and spawning continued 13-48 days after adults stopped migrating. These findings further corroborate recent discoveries that suggest alewife exhibit asynchronous spawning and has large implications for freshwater foodwebs. Lakes, overall, did not produce the same sized fish and there appears to be substantial variations of length-at-age with some lakes exhibiting large differences. No change in length-at-age occurred in August, thus differences were achieved earlier in the growing season. Additionally, all 20 lakes exhibited variable growth, density, and mortality rates that yielded generally weak relationships with abiotic and biotic factors. Juvenile alewife density was positively related to juvenile density in the previous sampling Round, suggesting that a single sampling date may be sufficient to estimate relative lake density across the landscape. Factors affecting growth were not consistent; overall growth was positively correlated with DOC, while the last 20 days of growth was negatively correlated with secchi depth. While different, these responses are likely the result of the same mechanisms, both intrinsically linked with zooplankton abundance, prey availability, and feeding behavior within lakes. No significant correlate was found for mortality. In the future, the data in this thesis can be incorporated into models to improve stock assessments and support timely adaptive management strategies.

The BMW in-line six-cylinder engine has been modified and introduced to production in the new BMW 3 Series model. Its major features include variable intake and exhaust camshaft timing, a new induction system with resonance charging, a turbulence-generating system in the intake ports and a new exhaust system with two closed-loop, coupled catalysts integrated into the exhaust manifold. The cam timing of both camshafts can be adjusted continuously within a range of 40° crank angle (CA) for the inlet cams and 25° CA for the exhaust cams. The turbulence-generating system supplies combustion air to the engine during part load operation and produces the necessary charge motion to run the engine with greater valve overlap at low loads and speeds. Its combination with variable camshaft timing results in lower fuel consumption and exhaust emissions that meet the LEV emission standard. In addition, the variable cam timing raises the torque curve of the unthrottled engine, particularly at low engine speed. The maximum values for torque and power output are unchanged, but maximum torque is reached 500 r/min earlier than with the previous engine.

This dissertation investigates the effect of education on the chances and age of marriage during the transition from adolescence into young adulthood among Kenyan women age 15-22. Women who receive more education are more likely to delay marriage. The literature suggests that occupation and age at sexual debut are also significantly associated with age of marriage. This study considers how these and other factors may possibly affect the life course of women in Kenya over a period of time and increases our understanding of marriage predictors. Data comes from the 2003 and 2008 Kenya Demographic and Health Surveys. Binary logistic and OLS regression models are used to analyze and compare the data. The results imply that while education has a statistically significant and strong positive effect on a woman's marital status as well as age of marriage, the effect of education on age of marriage has not changed since the introduction of Kenya's free primary education program.

Optimal delivery of instruction is both critical and challenging in dynamic, scenario-based training (SBT) computer simulations such as those used by the military. Tasks that human instructors must perform during these sorts of simulated training exercises can impose a heavy burden on them. Partially due to advances in the state-of-the-art in training technology and partially due to the military's desire to reduce the number of personnel required, it may be possible to support functions that overburdened instructors perform by automating much of the SBT process in a computer simulation. Unfortunately though, after more than 50 years of literature documenting research conducted in the area of training interventions, few empirically-supported guidelines have emerged to direct the choice and implementation of effective, automated training interventions. The current study sought to provide empirical guidance for the optimal timing of feedback delivery (i.e., immediate vs. delayed) in a dynamic, SBT computer simulation. The premise of the investigation was that the demand for overall cognitive resources during the training exercise would prescribe the proper timing of feedback delivery. To test the hypotheses, 120 volunteers were randomly assigned to 10 experimental conditions. After familiarization on the experimental testbed, participants completed a total of seven, 10-minute scenarios, which were divided across two training phases. During each training phase participants would receive either immediate or delayed feedback and would perform either high or low cognitive load scenarios. Four subtask measures were recorded during test scenarios as well as subjective reports of mental demand, temporal demand and frustration. Instructional efficiency ratios were computed using both objective performance data and subjective reports of mental demand. A series of planned comparisons were conducted to investigate the training effectiveness of differing scenario cognitive loads (low vs. high), timing of feedback delivery (immediate vs. delayed), and sequencing the timing of feedback delivery and the cognitive load of the scenario. In fact, the data did not support the hypotheses. Therefore, post hoc, exploratory data analyses were performed to determine if there were trends in the data that would inform future investigations. The results for these analyses are discussed with suggested directions for future research.

The work described here has been carried out to obtain a better understanding of the tooth root cracking failure mode of timing belts. Previous work has demonstrated the close dependence of this on the tooth deflections of fully meshed teeth, generated by torque transmission, but has not considered the additional distortions generated in the partially meshed conditions at entry to and exit from a pulley groove. Approximate compatibility and constitutive equations are combined with a rigorous consideration of tooth equilibrium in partial meshing to show how bending moments are generated at both exit from a driven pulley and entry to a driving pulley. Experimentally determined belt lives correlate very well with a combined measure of fully meshed tooth strain and strain due to bending at entry or exit. The analysis also shows that this strain measure reduces with increasing belt tooth stiffness, confirming the importance of a high tooth stiffness for a long belt life. Tooth force variations through the partial meshing cycle have also been predicted and compared with measurements obtained from a special strain gauge instrumented pulley. A greater pulley rotation than is predicted is required for a belt tooth to seat in a pulley groove. There is room for improvement in the modelling

<p> This thesis deals with the theory and application of semi-conductor detectors to timing measurements. The theory section discusses the charge collection times in the coaxial detector. The third chapter describes the experimental procedure for the γ-γ coincidence work, and the fourth part reports the results of studies of the timing characteristics of the coaxial detector.</p> / Thesis / Master of Science (MSc)