Research investigating the effects of pre-exercise meals with varying glycemic indices on exercise performance in intermittent sports is scarce. This study determined whether whole foods of low glycemic index (GI) resulted in a metabolic and performance advantage, in comparison to high GI foods, when eaten prior to extended intermittent cardiovascular exercise, such as tournament soccer play. Consenting trained participants (10 males, 4 females, 25.8 ± 7.3 y) completed two simulated soccer tournaments separated by at least seven days. Each testing day included two 90-minute soccer matches separated by a three hour break. Using a randomized cross-over design, low-GI, lentil-based meals (GI~42) or high-GI, potato-based meals (GI~78) matched for caloric value were consumed two hours prior to and then within one hour after the first soccer match. Blood glucose, lactate, insulin, free fatty acids, and respiratory gases were measured throughout the post-prandial and testing periods. Ratings of perceived exertion (RPE) and gastrointestinal symptoms were also recorded. Performance was measured by the distance covered during five one-minute sprints, separated by two minute and thirty second rest intervals, at the end of each match. Peak post-prandial blood glucose was higher (p<0.05) in the high-GI trial (8.9 ± 2.2 molL-1 [SD]) compared to the low GI trial (5.9 ± 1.3 mmolL-1) as was insulin prior to the start of exercise (19.4 ± 2.0 versus 9.2 ¬± 1.3 umolL-1, p<0.05). Blood lactate levels were significantly higher (p<0.05) at the end of the second match during the high-GI trial (6.1 ± 1.2 mmolL-1) compared to the low-GI trial (2.5 ± 0.4 mmolL-1). Breath-by-breath analysis showed lower (p<0.05) carbohydrate oxidation during the low-GI trials compared to the high-GI at the start of the first soccer match (p<0.05). Subjects reported greater feelings of hunger during the high-GI trial versus greater feelings of fullness during the low-GI trial (p<0.05), but RPE during the low-GI (14.1 ± 0.3) was similar to the high-GI meal (14.2 ± 0.3). Sprint distance was not significantly different between treatments (p=0.27). Overall, these findings suggest that lentil-based, low-GI foods are a comparable alternative to traditional high-GI pre-exercise meals, as they result in similar performance outcomes but improved metabolic profiles. Over the long-term, improving metabolic conditions during exercise may be beneficial to the health of athletes.

UDP-galactopyranose mutase (UGM) is a flavoenzyme which catalyzes the interconversion of UDP-galactopyranose (UDP-Galp) and UDP-galactofuranose (UDPGalf). UDP-Galf is the active precursor of Galf residues. Glycoconjugates of Galf residues are found in the cell wall of bacteria and on the cell surface of higher eukaryotes. Galf residues have not been found in humans and the fact that they are essential for the growth of pathogenic bacteria makes UGM a potential antibacterial target. In the present study, crystal structures of UGM from Deinocococcus radiodurans (drUGM) in complex with substrate (UDP-Galp) were determined. UDP-Galp is buried in the active site and bound in a U-shaped conformation. The binding mode and active site interactions of UDP-Galp are consistent with the previous biochemical and mechanistic studies. The mobile loops in the substrate complex structures exist in a closed conformation and Arg198 on one of the mobile loops stabilizes the phosphate groups of the substrate. The anomeric carbon of galactose is 2.8 Å from the N5 of FAD (in the reduced complex) favorable to form FAD-galactosyl adduct. In addition to substrate complex structures, the crystal structures of drUGM in complex with UDP, UMP, and UDP-Glc have been determined. The mobile loops in all these complexes exist in a closed conformation. Inhibitors for UGM were identified by ligand-based and structure-based methods. The phosphonate analog of UDP-Galp (GCP) showed only weak inhibition against various bacterial UGMs. The structure of drUGM in complex with GCP provided a basis for its inhibitory activity. Poor stabilization of the phosphate groups by conserved arginines (Arg198 and Arg305) and altered sugar binding mode account for its activity. Novel indole-based (LQ1, LQ6 and LQ10) inhibitors of UGM were identified through structure-based virtual screening (SBVS) of a chemical library. Inhibition studies also allowed the identification of an active site aspartic acid that plays role in inhibitor binding. The structural studies on drUGM provided a basis for understanding substrate binding to UGM. In vitro enzyme inhibition studies allowed the identification of novel indole-based inhibitors. The structural and inhibition studies reported here enhance the understanding of UGM-ligand interactions and will assist in the development of more potent inhibitors of UGM.

This thesis focused on modeling and simulation of simultaneous switching noise in packages as well as integrated circuits and the focus was mainly on the latter. Efficient and accurate methods have been developed for modeling the coupling due to SSN in multi-layered planes arising in electronic packages, extraction of the power grid in integrated circuits and simulation of the power supply noise in large size networks arising in power distribution network. These methods include conformal mapping, finite difference time domain and cavity resonator methods, using which the electrical performance of the power distribution system in a high speed electronic product can be predicted. The model developed for field penetration captured the effect of the magnetic field penetrating through planes in multi-layered packages. Analytical model for the extraction of the interconnect parasitics for a regular on-chip power grid has been presented. Complex image technique has been applied for modeling the dispersive interconnect on lossy silicon substrate. The Debye rational approximation has been used to approximate the RLGC parameters in order to simulate the frequency dependent elements in the time domain. The simulation of the entire network of the full-chip power grid has been carried out using the modified FDTD expressions. Several aspects of characterizing the generic on-chip power distribution network have been presented. The crossover capacitance has been evaluated using analytical model derived from conformal mapping. An analytical model has been proposed to extract parameters of on-chip multi-conductor transmission lines, which guarantees the stability and is applicable to general distribution of multi-conductor transmission lines. The above modeling procedures have been incorporated into a computer program, which generates the power grid model from the layout of chip power distribution networks automatically. Research on 3-D on-chip power distribution networks has been presented. The complex image technique has been extended from microstrip-type interconnects to stripline-type interconnects. Macromodel images have been derived with closed form expressions to capture the loss mechanism of the multiple conductive substrates. The effect of 3-D integration on switching noise has been illustrated in the time domain using examples.

In this dissertation, the development of an experimental prototype for on-board optical-to-electrical signal broadcasting at 10 Gb/s per channel over an interconnect distance of 10 cm was presented. The optical distribution network was implemented using a polymer-based 1-by-4 multimode interference (MMI) splitter with linearly tapered output facet. A 1-by-8 MMI splitter with input/output waveguides of 10 microns in width was first fabricated using standard photolithography and characterized at 40 Gb/s in NRZ format and PRBS = 2^7-1. The pulse response of MMI devices was further quantified from the time-dependent, pulse-modulated field propagation perspective incorporated with various dispersion mechanisms. The results predict their operating limitations and investigate why and how such devices become non-functional in the ultrashort-pulse limit that is far beyond the most present-day optical systems. The guided-mode attenuation associated with polymer waveguides fabricated on FR-4 printed-circuit boards was also investigated for the first time. The rigorous transmission-line network approach was applied and the FR-4 substrate was treated as a long-period substrate grating with rectangular corrugations. The peaks of attenuation were shown to occur near the Bragg conditions that were recognized as the leaky-wave stop bands. As the buffer layer thickness increases, the attenuation becomes negligibly small that is attributed to the weak grating-induced perturbation to the mode behavior. The prototype was then developed on the basis of both experimental verifications to the devices and theoretical investigations. An improved 1-by-4 MMI splitter at 1550 nm with linearly tapered output facet was heterogeneously integrated with four p-i-n photodetectors (PDs) on a silicon (Si) bench. The Si bench itself was then hybrid integrated onto an FR-4 printed-circuit board with four receiver channels composed of transimpedance amplifiers, limiting amplifiers, and surface-mounted components. The innovative integration approach demonstrated the simultaneous alignment between multiple waveguides and multiple PDs during the MMI fabrication process that is a complete radical departure from the conventional assembly method inherent from the telecommunication industry. The entire system was fully functional at 10 Gb/s per channel.

Novel fabrication technologies for high performance electrical and optical chip-to-substrate input/output (I/O) interconnections were developed. This research is driven by the long term performance and integration requirements of high performance chip-to-substrate I/Os, as well as the package reliability demands from semiconductor manufacturing. An electroless copper plating and annealing process was developed to join copper structures to achieve chip-to-substrate assembly by all copper pillar interconnects. The developed copper pillar interconnects provide much higher current carrying capability for chip-to-substrate power/ground input/output distributions and have low electrical parasitic characteristics for high frequency electrical signal communications. This copper bonding process also demonstrates the capability to compensate for misalignments and height variations of bonded structures. A finite element generalized plane deformation model was employed to design fully compliant copper pillars to eliminate the need of underfill. Electrical parasitics of copper pillar chip-to-substrate interconnects were studied by the derived formulas for low parasitic requirements. An optimized dimension space for all the criteria was provided on the pillar dimension chart. A novel nanoimprint lithography was developed to combine with photolithography in one process to create high quality features on a macrostructure for chip-to-substrate optical I/O applications. This fabrication process also demonstrated the capability to produce off-angle complex structures.

In this study, we demonstrated a flexible cholesteric liquid crystal display using polymerization induced phase separation (PIPS) on a single substrate. Cholesteric liquid-crystal displays (ChLCDs) provide with color reflection owing to their periodic helical layer, without any optic device like polarizer or color filter. We discussed the influence of surface treatment and process conditions on PIPS, and improve the reflectivity of single substrate Ch-LC display from 9.05% to 19.27%.

As the microwave wireless communication systems growing rapidly, microstrip planar ceramic filters attract many attentions because of the advantages of small size, low cost, easy fabrication, higher performance and easy integration. In this thesis, several kinds of bandpass filters are designed for different operating purposes. First, two kinds of dual-mode bandpass filters are designed for 2.4 GHz wideband with the T-shaped I/O arranging in a straight way for easy integration. Second, the hook-coupling and insert-coupling structures are adopted for series connecting of the stepped-impedance resonator structures, and 2.4/5.2 GHz dual-band filtering properties could be achieved. Third, two open-loop rectangular ring resonators and U-shaped I/O are designed for 2.4/5.2 GHz dual-band bandpass filters with deep transmission zeros. The quarter wavelength stubs and groove structures are used for enhancing deep transmission zeros between two passband and ripples of the second passband, respectively. Fourth, the parallel positioned resonators with phase difference method are used to design the dual-band (1.23/2.4 GHz) and quad-band (1.23/2.4/3.5/5.2 GHz) bandpass filter with asymmetrical bandwidths and transmission zeros. In the thesis, high quality Al2O3 ceramic substrates are used to fabricate different kinds of bandpass filters for pattern minimization and low losses. The electromagnetic simulators, HFSS and IE3D, were used to adjust and optimize the associated parameters. The printing method was used to fabricate the proposed bandpass filters, which did not need using the FeCl3 to etch the Cu plate from the surface of Duroid or the FR4 substrates. The proposed filters are measured by Agilent-N5230A with the SMA connectors welding. Finally, the simulated and measured results of proposed bandpass filters are in good agreement.

The deformation between interface, adhesion mechanism and the transparency of multi-layer flexible electronics composite were discussed. First, ITO (Indium Tin Oxide), Al (Aluminum) and ZnO (Zinc Oxide) were sputtered on a PET (Poly Ethylene Terephthalate) substrate by PVD (Physical Vapor Deposition) sequentially, to form ZnO/ITO/PET and ZnO/Al/PET which is the essential multi-layer structure in the transducer of flexible electronics. ITO/PET structure was widely applied to the touch panel. PET substrate possesses a good optical penetrability, low thermal expansion coefficient and lower price. However, the heat-resisting and chemical stability are poor. In this study, we explore the feasibility of the PDMS (Polydimethylsiloxane) substrate. It not only possesses good optical penetrability, but also exhibits higher PH selectivity than PET. In the analysis, the periodic external force was pressed on the flexible composite films to realize the difference between before and after experiment. Then the composite films were examined by nanoindentation and nanoscratch system (Berkovich and Conical probe with the radius of curvature of 20nm and 10um), four-point probe and spectrometer to measure the mechanical, electrical and optical properties, respectively. To investigate the effect of external force on these composite films, the interaction of films was discussed through external force testing by nanoscratch test.

This study is separated into two parts. Firstly, the Ag thin film was deposited on substrates with different average roughness by sputtering to examine the effect of substrate roughness on optical reflection. The results exhibit 10 percent difference of reflectivity within several nanometer changing in average roughness, indicating the reflectivity is easily affected by surface roughness. Secondly, optical reflectivity and electrical resistivity of multi-component AgMgAl alloys, both crystalline and amorphous, were measured. The crystalline alloys exhibit high reflection in infrared region but a steeper drop in visible and ultraviolet regions. By contrast, amorphous alloys show a lower but relatively uniform reflectivity in the visible and infrared regions. In both cases, the reflectivity was observed to scale with the square root of electrical resistivity. The scaling law was explained based on classical reflection theory. The different scaling factors for crystalline and amorphous alloys could be rationalized by the difference in the mean free time of charge carriers. Moreover, the mechanical properties of crystalline and amorphous thin film alloys, including hardness and modulus, were measured by nanoindentation. The hardness of thin film metallic glasses (TFMGs) is obviously higher than crystalline metals, while the modulus of TFMGs is similar to crystalline metals.

The piezoelectric transducer for vibration-energy harvesting is constructed of a piezoelectric layer, bottom electrode and a top electrode. In order to obtain an appropriate transducer for the low-frequency operating; environmentally-friendly and long-term, the flexible substrate, the piezoelectric layer, and the additional mass-loading (tip mass) have been investigated thoroughly. This study investigates the feasibility of a high-performance ZnO and AlN based piezoelectric transducer for vibration-energy harvesting applications. Firstly, the piezoelectric transducer is constructed of a Cu/ZnO/ITO/PET structure. Both scanning electron microscopy and X-ray diffraction indicate that, among the favorable characteristic of the ZnO piezoelectric film include a rigid surface structure and a high c-axis preferred orientation. Hence, an open circuit voltage of 1.87 V for the ZnO piezoelectric transducer at a vibration frequency of 100 Hz is obtained by an oscilloscope. After rectifying and filtering, the output power of the generator exhibits an available benefit of 0.07 £gW/cm2 with the load resistance of 5 M£[. Secondly, this investigation introduces novel means of integrating high-performance piezoelectric transducers using single-sided ZnO and AlN films with a flexible stainless steel substrate (SUS304). Hence, the SUS304 substrate exhibits the long-term stability under vibration. The single-sided ZnO and AlN transducers are deposited on the SUS304 substrate at a temperature of 300 oC by an RF magnetron sputtering system. Scanning electron microscopy and X-ray diffraction of piezoelectric films reveal a rigid surface structure and a high c-axis-preferred orientation. A mass loading at the front-end of the cantilever is critical to increase the amplitude of vibration and the power generated by the piezoelectric transducer. The open circuit voltage of the single-sided ZnO power generator is 10.5 V. After rectification and filtering through a capacitor with a capacitance of 33 nF, the output power of the single-sided ZnO generators exhibited a specific power output of 1.0 £gW/cm2 with a load resistance of 5 M£[. Finally, this investigation fabricates double-sided piezoelectric transducers for harvesting vibration-power. The double-sided piezoelectric transducer is constructed by depositing piezoelectric thin films on both the front and the back sides of SUS304 substrate. The titanium (Ti) and platinum (Pt) layers were deposited using a dual-gun DC sputtering system between the piezoelectric thin film and the back side of the SUS304 substrate. Scanning electron microscopy and X-ray diffraction of piezoelectric films reveal a rigid surface structure and highly c-axis-preferring orientation. The maximum open circuit voltage of the double-sided ZnO power transducer is approximately 18 V. After rectification and filtering through a 33 nF capacitor, a specific power output of 1.3 £gW/cm2 is obtained from the double-sided ZnO transducer with a load resistance of 6 M£[. The variation of the power output of ¡Ó0.001% is obtained after 24-hour continuous test. The maximum open circuit voltage of the double-sided AlN power transducer is approximately 20 V. After rectification and filtering through a 33 nF capacitor, a specific power output of 1.462 £gW/cm2 is obtained from the double-sided AlN transducer with a load resistance of 7 M£[.