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Attention deficit hyperactivity disorder, or ADHD, is a common childhood disorder with the prevalence rate of 5-10%. The prevalence rate in Taiwan is around 7-8%. There have been many theories proposed to explain ADHD, and one of them focuses on the deficiency of essential fatty acids (EFA), particularly omega-3 polyunsaturated fatty acids (n-3 PUFAs). Studies have shown that there is a positive correlation between EFA deficiency severity and ADHD symptoms and a negative association between blood PUFAs levels and ADHD symptoms, but not all studies have shown consistent findings. Moreover, although there have been some clinical trials showing that n-3 PUFAs, commonly a combination of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), are effective in ADHD, the findings continue to remain controversial. Indeed, there is limited research on the effect of n-3 PUFAs on cognitive functions in children with ADHD. In addition, the mechanism underpinning the link between PUFAs, and ADHD is still unclear, although a role for cortisol and inflammation has been suggested. My PhD has addressed these research questions in a number of ways. First, I have performed systematic reviews and meta-analyses on the cortisol levels and PUFAs levels in ADHD, including both children and adolescents, and a systematic review and meta-analysis on the effects of n-3 PUFAs supplementation on ADHD symptoms and cognitive function in children with ADHD. Second, I have conducted a cross-sectional study comparing ADHD and typically-developing (TD) youth, and measured their salivary cortisol levels, 5 blood inflammatory biomarkers, neurotrophins and PUFAs levels. Next, I conducted a double-blind randomized controlled study (RCT) of n-3 PUFAs (EPA) in children with ADHD, and conducted cognitive function assessments, including Weschler Intelligence Scale for Children-Fourth Edition Digit Span Subtest (WISCDS) and Continuous Performance Test (CPT) measures, as the primary outcome; moreover, I have studied other ADHD severity measures and blood levels of inflammatory biomarkers and neurotrophins as secondary outcomes. In the systematic reviews and meta-analyses, children with ADHD had lower salivary cortisol levels (g = -.77, p = .04) and lower morning salivary cortisol levels (g = -1.21, p = .02), as well as lower levels of docosahexaenoic acid (DHA, g = -.76, p = .0002), EPA (g = -.43, p = .0002) and total n-3 PUFAs (g = -.58, p = .0001); moreover, n-3 PUFAs supplementation improved ADHD clinical symptoms scores (g = .38, p < .0001) and cognitive measures associated with attention (g = 1.09, p = .001). In the cross-sectional study, I have enrolled 98 with ADHD youth (mean age 9.32 + 3.05 years, 86% males) and 21 TD youth (mean age 9.19 + 2.96 years, 71% male). The ADHD youth have lower levels of bedtime salivary levels (p = .030), brain-derived neurotrophic factor (BDNF, p < .0001), tumor necrosis-factor alpha (TNF-α, p = .009), Linoleic acid (LA) (p = .003) and DHA (p = .018), and higher levels of high-sensitivity C- reactive protein (hs-CRP, p < .0001) and interleukin (IL-) 6 (p < .0001) than TD youth. 6 In the RCT of n-3 PUFAs (EPA 1.2g) supplementation, I have enrolled 105 children and adolescents with ADHD, and 98 had completed the 12-week RCT. The n-3 group with the lowest baseline EPA level has a greater improvement in the CPT measures, hit reaction time (HRT, p = .009), HRT standard deviation (HRTSD, p = .043) and HRT interstimulus interval changes (HRTISIC, p = .005); such findings are not present in the group with moderate and high baseline EPA levels. Moreover, n-3 group with the highest baseline hs-CRP has a greater improvement on WISCDS longest digit span backward score (p < .001), WISCDS digit span backward score (p = .001), WISCDS total score (p = .026) and prosocial behavior (p = .021). There were no significant changes in the parent-, teacher- and youth-reported ADHD symptoms, emotional symptoms, and blood levels of inflammatory and neurotrophin biomarkers between n-3 and placebo group. In conclusion, my findings provide evidence that ADHD youth have lower PUFAs, cortisol and BDNF levels, and a higher state of inflammation than TD youth. My findings further supported the efficacy of n-3 PUFAs, especially EPA, in improving inattention and vigilance associated cognitive measures in ADHD with a low EPA level at baseline; and improving working memory and prosocial behavior in ADHD with high baseline inflammation status. Further research is needed to explore the effects of EPA on the clinical symptoms of ADHD targeting a larger sample size of youth with different nutritional and inflammatory status.

‘Abd al-Qāhir al-Jurjānī (d. 471/1078 or 474/1081) was a grammarian and literary theorist whose two works Dalā’il al-i‘jāz (Proofs of the Inimitability of the Qur’ān) and Asrār al-balāgha (The Secrets of Eloquence) laid the groundwork for ‘ilm al-balāgha (the science of eloquence) in Arabic literary theory. Al-Jurjānī began his work by focusing on the concept of the inimitability of the Qur’ān (i‘jāz al-Qur’ān) and extended it by devising a comprehensive theory of eloquence. He claims that naẓm (construction) is the basis of eloquence, which is not a random combination of sounds but requires the operation of the mind to organize the intended words. The structure of a grammatical composition is determined by its meaning, and the determinant of eloquence is the interrelationship of syntax and semantics. In his theory of majāz (figurative language), al-Jurjānī claims that it occurs when the underlying meaning is diverted to another or when one intends to broaden the scope of meaning. Al-Jurjānī introduces two types of majāz: majāz lughawī (a lexical trope) and majāz ‘aqlī (a mental trope). The former occurs when the majāz happens in the muthbat (the affirmed object) and the latter when it happens in the ithbāt (affirmation). Every isti‘āra (metaphor) is a majāz, and the process of creating an isti‘āra is not merely the transference of a name; it expresses a unique relationship between two entities by borrowing a meaning from one entity and attributing it to another. As for his notion of kināya (descriptive periphrasis), al-Jurjānī defines it as the intentional use of one or more words to convey a meaning other than the words’ conventional literal meaning; meanwhile, the literal language itself does relate to reality.Cognitive linguistics emerged in the 1970s as an approach to the study of linguistic thought and practice. Since the publication of George Lakoff and Mark Johnson’s Metaphors We Live By (1980), analyses of the use of figurative language, particularly metaphor and metonymy, have been one of the more fruitful areas of cognitive linguistic study. Cognitive linguists view discourse as the means of human knowledge and of the communication of human consciousness. The words used in discourse should be constructed in a particular pattern that is meaningful and presupposed by the intellect. Metaphor is an inherent part of the human conceptual system, an element of everyday language that involves a cognitive process that enhances comprehension via mapping between domains. On the other hand, metonymy is not considered a linguistic substitution but does involve a cognitive process through which we are able to access a mental entity by means of another entity. This dissertation examines al-Jurjānī’s theories to engage them in a dialogue with Cognitive Linguistics. Both al-Jurjānī and cognitive linguists agree that grammar is meaningful, emphasize the process of “conceptualization” in the production of meaning, stress the interrelationship of semantics and syntax, and underscore how grammatical construction itself functions in figurative speech to evoke hidden meanings. I demonstrate that both traditions view metaphors as relating to intellectual concepts rather than reflecting only a linguistic aspect. I also examine the “blind translation” of metonymy, which is generally considered equal to the Arabic kināya, but I argue that majāz ‘aqlī and one branch of majāz lughawī that al-Jurjānī illustrates could be other options. Adopting a cross-linguistic and cross-cultural perspective, this dissertation provides a comprehensive guide to how figurative language functions and is understood both in the framework of al-Jurjānī’s theory and in the cognitive linguistic approach. It shows that language is not independent of the mind but rather reflects the human perceptual and conceptual understanding of the world.

In this thesis, I strive to expose societal rules and regulations that constrict and restrict our social interactions in a way that promotes prejudice and xenophobia. Through interacting with the series of sculptures, viewers are given the opportunity to question these societal norms and start a process of self- reflection to truly understand the freedom that comes without prejudice. Interaction is the main element that ties the series of works together, to form a seamless journey of self-discovery. The following artists are discussed in relation to this series of work: Niki de Saint Phalle and Björk Guðmundsdóttir. Their art works share the same spirit of liberation and social revolution.

Light-pulse atom interferometers have been used as quantum inertial sensors and for precision tests of fundamental laws of physics. For higher contrast, we apply conjugate Ramsey-Borde interferometers to cancel out vibrational noise and top mirror tilting to compensate the Coriolis force. For higher sensitivity, we implement Bragg diffraction and Bloch oscillations for large momentum transfer to increase the enclosed area of our atom interferometer. We also utilize Raman sideband cooling in our experimental setup, which increases the overall signal about twentyfold, and increases the contrast by suppressing the thermal expansion of the atom cloud.By combining measurements of recoil frequency and a frequency comb, we present the first clock referenced to the mass of a single particle. The rest mass of a particle defines its Compton frequency, mc^2/h through relativity and quantum mechanics, and thereby sets a fundamental timescale. Our clock stabilizes a 10 MHz radio frequency signal to a certain fraction of the cesium Compton frequency. Future work could result in an elementary particle (electron) or even antimatter (antihydrogen) clock, opening up new ways to test CPT symmetry and the equivalence principle. We also present our progress towards a new determination of the fine structure constant. The fine structure constant value obtained by our cesium Compton clock measurement is about three times better compared with the earlier cesium recoil frequency result. After combining Bragg diffraction and Bloch oscillations, we achieved 0.33 ppb sensitivity (0.66 ppb uncertainty of the recoil frequency measurement) in 6 hours, which is about two times better than the previous best recoil frequency measurement. The leading systematic effect is also reduced by a factor of 2.75.

The number of studies addressing the possible effects of air pollutants on human reproduction, especially prenatal outcomes, has grown extensively. However, the plausible biological mechanisms by which air pollutants influence prenatal outcomes remain unclear. The aims of this dissertation are (1) to determine whether ambient air pollution exposure (including particles of less than 10 µm (PM10) and less than 2.5 µm diameter (PM2.5), carbon monoxide, nitrogen dioxide, sulfur dioxide, and ozone) contributes to increased inflammatory response by measuring C-reactive protein (CRP) concentrations during early pregnancy, and (2) to examine associations between ambient air pollution exposures and blood pressure changes during pregnancy. In addition, because smoking during pregnancy is a risk factor for some adverse birth outcomes such as preterm delivery, and inflammation has been suggested to increase the risk of preterm delivery, the other aim of this dissertation was to examine whether systemic inflammation mediates the link between smoking and preterm delivery. The study population was selected from the Prenatal Exposures and Preeclampsia Prevention study (PEPP) conducted in Pittsburgh, PA between 1997 and 2001. Space-time Kriging interpolation for ambient station measures at the maternal ZIP code was performed to estimate maternal air pollution exposure. Multiple linear and logistic regressions were employed to evaluate associations between air pollution, CRP concentrations, and blood pressure changes during pregnancy. Positive associations between particulate (both PM2.5 and PM10) and ozone air pollution and elevated CRP concentrations in non-smoking women during early pregnancy were observed. For blood pressure changes, we found that first trimester exposure to PM10 and ozone air pollution was associated to increases in mean systolic and diastolic blood pressure changes during pregnancy. For smoking and preterm study, no evidence that systemic inflammation mediates this association was found. Our findings provide some new evidence that associations between particulate air pollution and adverse birth outcomes may be mediated by systemic inflammation and blood pressure changes. These findings have considerable public health significance to further prevent the adverse birth outcomes associated with air pollution exposure.

Trade in services is the largest and fastest growing sector in the global economy, and tourism, of which hospitality is the core element, is a significant component of this. Through the growth and expansion of food and accommodation services in recent years, many career opportunities have been created in this sector. Despite increasing customer numbers and consequential demand for staff, the hospitality industry has a high employee turnover and is unable to recruit and retain sufficient skilled employees, even with a large number of training providers throughout New Zealand. This research investigated the variables that currently moderate employee job satisfaction, career paths and career commitment and what relationship these may have to the staff turnover rate in the New Zealand hospitality industry. The target of this study was non-supervisory employees in hotels, restaurants, cafes and bars to represent the wider hospitality industry in New Zealand. This project used self-completion survey questionnaires which were distributed to staff through employers / managers. Extensive statistical tables are included to show respondents' ratings of each of the items used in the research instrument. Also, reported the differences between the ratings by various sub-groups based on independent variables, including gender, age, number of dependants, workplace, job position, education level, prior work experience and associated hospitality training. Predominant analysis was quantitative but also incorporated some qualitative data analysis. No distinct statistically significant differences were found in the sub-groups based on gender, number of dependants, job position, prior work experience and having associated hospitality training. In other words, employees' levels of satisfaction about employment and commitment to hospitality were not apparently related to these independent variables. However, significant differences were found in terms of age, workplace and education level. Through correlation analysis, this research found that there is a positive relationship between employee satisfaction and commitment; and there is a negative relationship between employee commitment and leaving intention. Qualitative data reported that low pay, long working hours and poor working conditions are the crucial reasons that respondents do not like their jobs. Some research limitations, recommendations, future research and suggestions for this industry were also provided in the study.

In this thesis, various photonic crystal (PC) devices with quantum dot (QD) heterostructures have been theoretically and experimentally investigated for applications of spontaneous emission control and photonic integrated circuits (PICs). First, a three-dimensional (3D) quasi-mode analysis has been developed for two-dimensional (2D) PC defect microcavities with complex vertical heterostructures. This analysis has been incorporated with the calculation of eigenstates in an InAs/GaAs pyramidal QD to investigate the spontaneous emission characteristics of self-organized QDs embedded in PC microcavities. As a result of both reduced cavity size and increased cavity Q, simulations show that the spontaneous emission enhancement factor (∼14), and coupling efficiency (∼97%) have been greatly improved for a high Q (∼1000) PC-VCSEL microcavity. The coupling efficiency in a low Q (∼200) PC-slab cavity reaches a sufficient level (∼67%) by simply reducing the cavity size. Second, electrically-injected PC light sources with a QD active region and a horizontally-coupled defect waveguide have been realized. The mode coupling mechanism between a PC cavity and the adjacent waveguide has been investigated with direct and transverse coupling schemes. Device spectral characteristics confirm that strong mode coupling occurs only at the anti-crossings of transversely-coupled PC defect waveguides and cavities. Third, PC-based resonant cavity photodiodes coupled with a PC waveguide have also been realized using the same twin-guide QD heterostructure as in the PC emitters. The measured spectral photocurrent characteristics demonstrate enhancement and narrowing (∼10nm) of the photoresponse at lambda ∼ 1.3mum, which is explained by a model involving circulating fields in the cavity. A spectral dip, ∼10nm in width, is also observed at 1.3mum, and may be due to the anti-crossing mechanism uniquely present in PC waveguides. In addition to PC active devices, a relatively simple technique to fabricate 3D GaAs-based PCs has been developed by means of alternate-layer deposition on a 2D patterned substrate. The fabricated devices exhibit a transmission stopband ∼10dB along surface normal. This dissertation will aid in the realization of miniature (∼40mum), electrically-injected PICs, such as microfluidic sensors for biomedical or environmental monitoring. This can be achieved by monolithically integrating the PC-waveguide-coupled emitters and detectors on the same chip.