Cheng Kin-wing. / "May 1999." / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Thesis. 1976. M.S.--Massachusetts Institute of Technology. Dept. of Mechanical Engineering. / Microfiche copy available in Archives and Engineering. / Includes bibliographical references. / M.S.

Over the last twenty years, a main focus of low-dimensional topology has been on categorified knot invariants such as knot homologies. This dissertation studies the case of two such homologies under the iteration of branched covering maps. In the first part, we find a spectral sequence on the sutured annular Khovanov homology of periodic links of period $r=2^i$. In the second part, we study the asymptotic growth rate of Heegaard Floer homology of cyclic branched covers of a knot as the branching number increases.

Quality of life (QoL) questionnaires have been suggested as the most appropriate way to measure the effectiveness of low vision rehabilitation. However, several research studies have not been able to detect differences in effectiveness between rehabilitation strategies. The hypothesis of this study is that there are other factors, unrelated to vision, influencing the scores obtained in these questionnaires and masking the changes achieved by rehabilitation. The suggestion is that patients' realistic acceptance of, and successful adaptation to, their visual loss is influenced by psychosocial factors such as; personality, religious beliefs, social support, general health (i.e. mental and physical), understanding of their eye condition, level of education, and financial status. Concurrently, a parallel study was conducted with children. As with the adult arm, the aim of the study was to understand whether quality of life, and social behaviour and relationships in children with a visual impairment were related to the vision loss, vision rehabilitation, or non-visual factors. Patients attending the Manchester Royal Eye Hospital low vision clinic between May 2009 and August 2010, were recruited: 448 patients between 18 and 96 years old, with best-corrected binocular visual acuity smaller or equal to6/18, and 62 children between 5 and 16 years old. Telephone delivery of previously validated questionnaires was used with adult patients and parents of child patients; face-to-face interviews were completed by children. Both studies showed how psychosocial factors were stronger determinants of quality of life in people with low vision, than traditional low vision rehabilitation using optical aids. In the case of adults, physical and mental health appeared to be major predictors of quality of life, adaptation to the vision loss and participation restriction. In the case of children, visual acuity at distance and near, contrast sensitivity (CS), age, and parents' coping strategies appeared to determine quality of life and children behaviours. The final element of this work was a pilot study to attempt to address issues causing poor quality of life. Seventy-one participants who scored low in the Low Vision Quality of Life Questionnaire (LVQOL-25) (i.e. below 62.5) were given the opportunity to enrol for the Expert Patient Programme, which is a self-management programme aimed at adults with chronic health problems or disabilities. Only 2 participants expressed an interest in the programme, and none of them actually took part.

In this thesis study, the surface/interface plasmon excitations in different Si nanostructures were revealed through the EELS study in TEM/STEM. In the case of the planar boundary such as the wedge-like specimen, the spatially resolved EELS results disclose the dependence of the intensity and the position of the interface plasmon peak on the sample thickness. In the case of the Si-core/ SiO2-shell nanoparticles, we found that the SP/IP peak will firstly red-shifts with the increase of the SiO2 shell thickness and eventually levels off . As the aspect ratio of the Si nanoparticles increases, (from spherical particle to nanorod and nanowire), the SP/IP will split into two branches: transverse and longitudinal modes. We also found the intensity ratio of the transverse/longitudinal mode excitations depends on the diameter of the Si core size in the nanostructures. In the one-dimensional interacting Si nanoparticle chains, the Si nanoparticles were embedded in the SiO 2 shell, the splitting of the SP excitation into transverse and longitudinal modes was also observed. As the inter-particle distance reduces to several nanometers, the coupling of the IP excitation between the adjacent particles becomes significant, and results in the local field enhancement in-between the two particles. This is directly visualized using EFTEM imaging in TEM/STEM. / Surface/interface plasmons (SP/IP) are the plasmons confined at specific boundaries, describing the surface/interface charge density oscillation. They are generated when the scattered electromagnetic wave with its scattering vector component parallel to the boundary propagates along the surface/interface. Study of surface plasmon resonance in noble metals such as gold and silver nanoparticles have started decades ago, and recent interests are focused on the plasmonic properties of individual nanoparticles, as enabled by the size/shape control in the nanostructure growth and advances made in the characterization methodologies. Besides the noble metals, semiconductor such as silicon also attracts much attention for its plasmonic behavior. The surface/interface plasmon resonance frequency of Si-based nanostructures occurs at relatively higher energies (compared to Au and Ag), making it a perfect system to be studied using electron energy loss spectroscopy (EELS) based techniques. When performed in a scanning transmission electron microscope (STEM), such a technique enjoys excellent spatial resolution, and can map the local plasmonic properties of individual nanostructures. / The plasmon excitation depends sensitively on not only the material dielectric properties but also the geometrical configurations of the material. In the present thesis work, silicon-based nanostructures with planar, spherical, and cylindrical boundaries were investigated using both experimental and theoretical approaches, with focus on the plasmon oscillation originating from the Si/SiO 2 interface. The specimens employed include silicon/silica thin films, Si-core/SiO2-shell nanoparticles with different aspect ratios and spherical-shaped nanoparticle chains, as well as Si-core/SiO2-shell nanocables. / Wang, Xiaojing = 低維硅納米結構表界面等離激元之研究 / 王笑靜. / Adviser: Li Quan. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 118-122). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Wang, Xiaojing = Di wei gui na mi jie gou biao jie mian deng li ji yuan zhi yan jiu / Wang Xiaojing.

This thesis explores space and gender in twenty-three Latin saints’ vitae from the thirteenth-century Low Countries. In the midst of urbanisation and rejuvenating apostolic zeal, the vitae emerged from a milieu in which groups of women who were unable or unwilling to pursue a traditional religious vocation chose to live a vita mixta, a combination of the contemplative and active life, while remaining in the world. Recent scholarship has moved away from viewing the women through the lens of institutionalisation. However, continued focus on the women’s ecclesiastical status and the labels used to describe them has implicitly maintained a lay/monastic binary, in which the women are compared against the monastic paradigm. The twenty-three vitae under examination detail the lives of both women and men (whose vitae offer a comparison) from different backgrounds and vocations. This wide-ranging selection of texts allows for a broad comparative textual analysis in order to consider where and how the women and men enacted solitary piety and communal devotion. Taking geometric space as its organising principle the thesis considers the dominant cultural configurations of space and its fluidity, noting how space could be transformed to suit the spiritual needs of individuals and groups. Solitude could be achieved in a variety of different settings from the bedchamber to wilderness while spaces such as streets, windows and cells could facilitate communal devotion. This connected women and men from different religious backgrounds. There are some surprising finds: in the vitae entry points such as windows and doors were fundamental to womens’ communal piety and women sought solitude in the wilderness more frequently than their male counterparts. Uncovering women from the shadows of male-authored texts remains a pertinent issue in histories of medieval women. Ultimately, this thesis’ adoption of a spatial framework provides a different avenue to explore the vitae and primarily the women described within.

With ageing comes a deterioration of metabolic and physiological changes that often manifest themselves as age-related comorbidities. Calorie restriction (CR) is a robust intervention that can prevent and reverse such changes, resulting in reduced ageassociated disease and increased lifespan across a wide range of species. Moreover, a link between the extent of restriction and increased lifespan has also been established. Though widely studied, the mechanisms behind the beneficial effects of CR have yet to be fully understood. Consequently, I investigated metabolomic changes in the liver, plasma, brown adipose tissue (BAT) and cerebellum in five month old male C57BL/6 mice undergoing three months of either 10, 20, 30 or 40% CR, in addition to 12 hour and 24 hour ad libitum fed groups. Behavioural, physiological and molecular data was collected on each individual mouse and I used this information, in addition to my own metabolomic data to determine associations between phenotypic changes with graded CR. My results indicate that increasing CR resulted in greater numbers of significantly differentiated metabolites across all four tissues, and these were related to changes across sphingolipids, carnitines, bile acids, vitamins and amino acids. Metabolic remodelling in the liver indicated a shift from lipogenesis to lipolysis and changes in the plasma indicated an increase in absorption of vitamins from the stomach and colon. Changes in neurotransmitters and their precursors suggested activity and temperature driven BAT activation, in addition to an increase in antioxidant power, this was also seen in the cerebellum where metabolites associated with signalling in the hypothalamus were increased in a graded fashion with CR. In all tissues changes were linked with behaviours that accompany hunger signalling such as increased food anticipatory activity and reduced body temperature. Together, these changes reflect multi-tissue beneficial effects of CR, which may function to alleviate age-related comorbidities.

An axial compressor for a domestic appliance can be designed to be smaller than an equivalent centrifugal compressor. However, the performance of such a compact axial compression system is limited by increased viscous losses and reduced flow turning at low Reynolds numbers ($Re$). In domestic appliance compressors, $Re$ is typically in the range $10^4$ - $10^5$. Although the aerodynamics of isolated aerofoils operating at these $Re$ have been studied extensively, the flow fields within low $Re$ axial compressors have not been investigated in detail. This dissertation aims to develop an improved understanding of loss variation at low $Re$ and to explore how the losses can be reduced through design changes. Experiments on a 5 times scaled-up single stage axial compressor have been conducted across a range of $Re$ of $10^4$ - $10^5$. The flow field has been characterised using detailed area traverses with a miniaturised five-hole probe at the rotor inlet, rotor exit and stator exit and a miniature hot-wire at the rotor exit. The probe was specifically designed and calibrated for the scale of the experiments and methods to improve the accuracy of the measurements have been applied including a probe geometry correction. The traverse experiments were performed at the design operating condition ($\phi=0.55$ and $Re= 6\times10^4$) and at a condition close to stall for a datum stage design, a stage with an improved stator design and two stators with compound lean. It was found that losses in the rotor were greater than the stator losses across the whole range of $Re$. As expected, the loss decreased with increasing $Re$ for both the stator and rotor. The losses were also increased by three-dimensional flow, with typical loss coefficients at the hub and tip of the blade rows in the range of $20-30\%$. A major contributor to the rotor loss was an unexpected hub separation that increased in size as $Re$ was reduced. At higher $Re$, the major loss sources were the rotor tip leakage, the stator wake and the stator hub separation. The results indicate that an improved stator design that accounts for the actual, measured, rotor exit flow field at low $Re$ could reduce the $Re$ at which blade row losses start to rise dramatically as well as reduce the loss across all $Re$. The improved stator design was better matched to the radial distribution of rotor exit flow angle, which led to a decrease in stator loss across all $Re$. For all stator designs, however, the measured stage stall margin was identical at all $Re$. This, along with the increase in velocity deficit in the rotor tip region at off-design indicates that stall occurred in the rotor and was neither $Re$ nor stator design dependent. The introduction of compound lean to the the stator design had the expected result of decreasing the endwall corner separation loss and increasing midspan losses. The experiments have shown that there was a loss increase in both the midspan and casing region much greater than the corresponding decrease in the stator hub. Also the mass flow redistribution in the experiments was larger that the redistribution predicted by the CFD. Three-dimensional RANS computations at low $Re$ of the same designs as experimentally studied were also conducted in order to investigate the predictive accuracy of industry standard CFD. The simulation results predicted the overall loss distribution but overestimated the end-wall losses and failed to capture the drop in stage performance at low $Re$. The differences with the experiments were caused by the inherent limitations of a fully turbulent solver that cannot reproduce transitional flow-features. Similarly to the experiments, there was no stall margin dependency on $Re$ in the simulations. This thesis has shown that with axial compressors designed specifically for low $Re$, the $Re$ at which the losses start increasing exponentially can be shifted from $10\times10^4$ to $ 4\times10^4$. The loss increase is predominantly caused by the rotor hub corner separation.

Phosphorus-boron multiple-bonds are of interest because of their predicted reactivity with small molecules; their potential as reagents for the synthesis of molecules isosteric to carbon analogues which exhibit conjugation; and because they have potential as nucleation sites for the solution-phase synthesis of boron phosphide. Phosphaborenes (RP=BR') have not yet been reported due to their propensity to oligomerise to dimers or trimers, even with bulky and electronically-stabilising substituents upon phosphorus and boron. Base-stabilisation at boron allows the isolation of phosphaborenes by preventing oligomerisation, although this alters the reactivity of the phosphaborene unit. An alternative method of studying phosphaborenes free of base or acid coordination is via their thermal generation from a phosphaborene dimer and subsequent in situ reactions with suitable substrates. Chapter 1 examines the potential uses of phosphaborenes in the context of other low-valent main group molecules. The likely reactivity of phosphorus-boron multiple bonds is discussed in the context of the iminoboranes (RNBR') and the isoelectronic heavier group 14 alkyne and alkene analogues. The use of unsaturated main group fragments to build molecular clusters is considered along with the potential role that phosphorus boron multiple bonds could play in preparing boron phosphide fragments. The uses and methods of preparation of group 13/15 containing molecules exhibiting conjugation are discussed, along with the possibility that phosphaborenes would be useful reagents to prepare new P-B/C-C isosteres. Chapter 2 looks at how base-promoted trimethylsilylchloride elimination can be used to prepare base-stabilised phosphaborenes from suitable precursors (RP(SiMe₃)B(X)R' and the mechanism of these reactions. The reactivity of base-stabilised phosphaborenes with Lewis acids is also examined. Chapter 3 covers how base-promoted (L = base) trimethylsilyl halide abstraction from functionalised precursors ((Me₃Si)₃P·BBr₃) can be harnessed to prepare new functionalised phosphinoboranes ((Me₃Si)₂PB(L)Br₂) and phosphaborenes (Me₃SiP=B(L)Br). A 1-dihydro-2-dibromo functionalised phosphinoborane H₂PB(Br₂)L can be prepared from Me₃Si)₂PB(Br₂)L. A subsequent base-promoted dehydrohalogenation yields the hydro-bromo substituted phosphaborene HP=B(L)Br. Chapter 4 examines the in situ thermal generation of a phosphaborene generated from a phosphaborene dimer and its reactivity with bases and unsaturated organic molecules to prepare 1,2-phosphaboretes and 1,2-phosphaboretanes. Chapter 5 explores the diverse reactivity of the 1,2-phosphaboretes. 1,2- phosphaboretes are capable of FLP-like insertion reactions with an isonitrile and carbon monoxide. They are also ring-opened by the coordination of a Lewis acid or base to phosphorus or boron respectively to give P-B containing butadiene analogues. The reaction of the 1,2-phosphaborete with phenyl acetylene proceeds via an unusual carbon-carbon bond cleavage to generate the first example of a 1,3- phosphaborine benzene analogue, rather than the expected 1,4-phosphaborine.

Virtually every industry and discipline (e.g., mining, pharmaceutical, construction, agriculture, reclamation, etc.) is finding applications for wireless data acquisition for monitoring and managing processes and resources. Two sectors, namely agriculture and environmental research, are seeking ways to obtain distributed soil and plant measurements over larger areas like a watershed or large fields rather than a single site of intensive instrumentation (i.e., a weather station). Wireless sensor networks and remote sensing have been explored as a means to satisfy this need. Commercial products are readily available that have remote wireless options to support distributed senor networking. However, these systems have been designed with a field engineer or technician as the target end-user. Equipment and operating costs, device specific programming languages, and complex wireless configuration schemes have impeded the adoption of large-scale, multi-node wireless systems in these fields. This report details the development of an easy-to-use, ultra-low power wireless datalogger incorporating a scalable, intelligent data collection and transmission topology. The final product can interface to various sensor types including SDI-12 and uses an LCD display to help simplify device setup.