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Triboelectrification, a contact-induced electrification where a material becomes electrically charged after brought into contact with a dissimilar one via friction [1], is an available, stable and efficient method to realize the mechanical-to-electrical energy conversion. Until now, this phenomenon has been investigated for insulators like polymers and silicon dioxide, and zero-bandgap semiconductor like graphene. For semiconductors with non-zero bandgaps, transition metal dichalcogenides have been paid much attention due to their distinctive optical, electrical and mechanical properties, and it has been reported that the performance of triboelectric nanogenerators can be dramatically enhanced by introducing single-layer MoS2 into the friction layer as the triboelectric electron-accepter layer [2], but the theories behind are still poorly understood, so the aim of this investigation is to fill this research gap. With this aim in mind, high-quality MoS2, WS2, MoSe2, and WSe2 nanoflakes were synthesized by chemical vapor deposition method and their triboelectric properties were characterized with atomic force microscopy and Kelvin force microscopy. Due to the various work functions of these four materials in reference to the conductive Pt-coated tip, the electrons are transferred from the samples to the tip during triboelectrification in the case of WS2, MoSe2, and WSe2 whereas MoS2 exhibits an opposite transfer direction. The densities of tribo-charges are different for these four materials but they can be modified by applying diverse biases to the conductive tip during the rubbing process. Impressively, these tribocharges, tunneling to the interlayer between the nanoflakes and the underlying insulating substrate, show more than two orders of magnitude longer lifetime than conventional triboelectrification, and MoS2 owns the longest lifetime while WSe2 has the shortest among these four materials. In addition, the diffusion processes of WS2 and MoSe2 are alike thanks to their similar work functions. The surface-adsorbed water molecules from the atmosphere can act as carrier trappers to affect the surface potential and charge distribution of 2D materials given the interaction with the environment nearby, but heat treatment can efficiently solve this problem. Besides, a positive correlation between the layer number and resistance to charge dissipation was observed, and there also exists the transfer of materials during the frictional process, which can be utilized for tuning the triboelectric properties of the rubbed material. On these basis, applicable fields consisting of bandgap modification as well as tunable antenna have been investigated. For the bandgap modification, the in situ effect of strain was investigated and it exhibits that the bandgap decreases monotonically with the increase of applied force. The reason behind is the reduction of orbital overlapping and hybridization due to the weakened atomic bonds when localized strain appears. In addition, while the bandgap of MoS2 is almost unchanged when an external perpendicular electric field is applied because of the very subtle band structure deformation, the bandgap of bilayer MoS2 can be modified via the electric field generated by the underlying tribo-charges, and applying positive and negative biases has different effects on the bandgap thanks to the spontaneous polarization along the direction perpendicular to the nanoflakes plane. Meanwhile, a MoSe2- based triboelectrically-controlled tunable antenna was proposed to apply to the upcoming 5G base station. As the tribo-charges can tunnel through the MoSe2 nanoflakes and localize at the interlayer to act as a bias voltage, the conductive/insulating states MoSe2 can be controlled, which results in the adjustable working frequency band from 28 GHz to around 38 GHz. In the meantime, a stable gain (less than 0.1 dBi variation in the whole range) is achieved for this omnidirectional antenna. Additionally, a unidirectional radiation can be reached with a metallic reflector placed at the back of the tunable antenna, and a broad beamwidth can still remain. Due to the long-term preservation of the tribo-charges, no extra bias is needed in this case and the energy can be saved to a large extent.

In this thesis, I present novel strategies for controlling objects with high degrees of freedom for the purpose of robotic control and computer animation, including articulated objects such as human bodies or robots and deformable objects such as ropes and cloth. Such control is required for common daily movements such as folding arms, tying ropes, wrapping objects and putting on clothes. Although there is demand in computer graphics and animation for generating such scenes, little work has targeted these problems. The difficulty of solving such problems are due to the following two factors: (1) The complexity of the planning algorithms: The computational costs of the methods that are currently available increase exponentially with respect to the degrees of freedom of the objects and therefore they cannot be applied for full human body structures, ropes and clothes . (2) Lack of abstract descriptors for complex tasks. Models for quantitatively describing the progress of tasks such as wrapping and knotting are absent for animation generation. In this work, we employ the concept of a task-centric manifold to quantitatively describe complex tasks, and incorporate a bi-mapping scheme to bridge this manifold and the configuration space of the controlled objects, called an object-centric manifold. The control problem is solved by first projecting the controlled object onto the task-centric manifold, then getting the next ideal state of the scenario by local planning, and finally projecting the state back to the object-centric manifold to get the desirable state of the controlled object. Using this scheme, complex movements that previously required global path planning can be synthesised by local path planning. Under this framework, we show the applications in various fields. An interpolation algorithm for arbitrary postures of human character is first proposed. Second, a control scheme is suggested in generating Furoshiki wraps with different styles. Finally, new models and planning methods are given for quantitatively control for wrapping/ unwrapping and dressing/undressing problems.

Heinrich Schenker's concept of the auxiliary cadence can be considered as a middleground manifestation of the Ursatz; his definition of the auxiliary cadence caters only to tonal compositions with a single background tonic, such as Brahms's songs. However, there exist compositions in which the a single background tonic cannot be easily ascertained. Such unorthodox compositions, in fact, can be found even prior to Brahms's songs. In such cases, although the opening and closing tonics are different and are often categorized as large-scale auxiliary cadence structured compositions, they do not operate within the single-tonic based tonal paradigm upon which Schenker formed his idea of the auxiliary cadence. Such compositions may be approached as a novel type of auxiliary cadence and described as "process-driven." The thesis presents and contrasts examples of both types of auxiliary cadences in songs by Schubert, Brahms, and Berg.

Elevated protein synthesis is a fundamental mechanism contributing to a growing heart, during which both translation efficiency and capacity are enhanced (8-10). Translation efficiency focus on existing ribosomes in the cytosol, involving how signaling pathways regulate translation initiation, elongation, termination and ribosome recycling to affect translation in a cell(11-14). In the cardiomyocytes, mRNA of MHC loading to the polysomes(15), phosphorylation of ribosomal protein, S6, or of the peptide chain initiation factor, elF-4E by mTOR (16) are well-characterized mechanisms of translation efficiency regulation. While little of translation capacity, or ribosome biogenesis in the heart has been explored. � In the heart, ribosome biogenesis is vital in rapid growth conditions such as cardiac development, hypertrophy and pulmonary artery stenosis(9). The left ventricular weight increases 82% in 4 days following birth in the newborn pig(17) serves as a good example illustrating that regulation of translation efficiency only cannot meet the demand of elevated protein synthesis.Biogenesis of ribosomes, the only and universal translation machinery in the cell, is a tremendous work. All three RNA polymerases, estimated 70% of mature ribosomes and more than 200 assembly factors are devoted in this tightly controlled process(7, 18, 19). It starts from rDNA transcription, the pre-ribosomal RNA 45S/47S is synthesized by Pol I, followed by ribosomal RNA processing in the nucleoli, carried out by ~150 exonucleases, processing factors and ribosomal subunit assembly factors. The rRNA stands as a scaffold to be decorated by ribosomal proteins, then exported into the cytosol as the 40S and 60S subunits. In the heart, regulation of this assembly chain is largely dark as only few studies examined the rDNA transcription level.In the thesis, we identified a long non-coding RNA Miat is associated with cardiac hypertrophy from an unbiased approach and analyzed the transcriptional change in the pressure overload mouse model to discover that Miat regulates the ribosomal genes and ribosome assembly associated genes. To confirm its impact on translation, we found that Miat is required for increased protein synthesis in cardiomyocytes. More remarkably, lack of Miat showed protective effect to the heart in multiple stress-induced cardiac growth models. Mechanistically, we found that Miat binds to nucleolin (NCL) via conserved binding motifs, and such binding is vital for ribosome biogenesis. NCL is a protein required for rDNA transcription and functions as the early processor of 45S/47S rRNA (1, 20, 21), however, how NCL mediates 45S/47S rRNA processing in the nucleoli region remained unknown. We found that Miat-NCL binding is vital for rRNA processing, nucleoli formation and ribosome biogenesis in the cardiomyocytes. Therefore, our study provided one of the first detailed examples of how ribosome biogenesis is regulated in the heart and how alteration of translation capacity affects cardiac function in pathological growth.

Abstract: Glycosaminoglycans (GAGs) such as chondroitin sulfate (CS), dermatan sulfate (DS), heparin (HP), heparan sulfate (HS), and non-sulfated hyaluronic acid (HA) are a group of complex polysaccharides exhibiting a wide range of biological functions. These macromolecules are structurally heterogeneous depending on the animal source, and their functional properties may also be affected by the specific purification procedure. The overall thesis objective is to investigate the bioproduction of GAG-derived sulfated oligosaccharides and study their effect on iron uptake by Caco-2 cells. The first study aimed to develop a food-grade approach for the extraction of GAGs from chicken cartilage and skin, which are low-value poultry by-products. Purified sulfated GAGs were successfully extracted from chicken cartilage (CS) and skin (CS/DS) using porcine pancreatin (a food-grade proteolysis) followed by ethanol precipitation and purification with anion exchange chromatography. In the second stage of this study, the antioxidant capacity of these chicken sulfated GAG polysaccharides and their respective oligosaccharides (oligos) obtained by enzymatic digestion were evaluated. Bovine trachea CS and porcine intestinal DS were used as controls. Then, their effect on iron uptake was evaluated by ferritin formation using an in vitro digestion in Caco-2 cell model. The CS-oligos derived from both CS polysaccharides of chicken and bovine sources possessed the greatest DPPH scavenging and ferric reducing activities (p < 0.05) but had limited ferrous chelating activities. Both chicken sulfated GAG polysaccharides and their controls showed greater ferritin formation compared to the blank (p < 0.05). Depolymerisation of CS polysaccharides further improved ferritin formation by two-fold in both the sample and control. The enhanced iron uptake through enzymatic CS depolymerisation may be due to the combined effects of reduced molecular weight, increased amount of hydroxyl terminal groups, and ferric reducing activities. Based on these results, the second study focused on supplementing enzymatic depolymerised bovine trachea CS into skim bovine milk (SBM) to verify if its promoting effect on Fe uptake can remain pronounced. The effect of CS-oligos with various SBM fractions on Fe uptake by an in vitro digestion/Caco-2 cell model was evaluated. SBM was separated into casein, whey, lactose and oligosaccharides by ultrafiltration. Modified fractions representing the absence of either casein, whey, or lactose were then prepared. Extrinsic ferrous sulfate was added since the intrinsic iron content of SBM is relatively low. The effect of milk oligosaccharides on Fe uptake was evaluated for the first time, which was similar to that of whey. The ferritin synthesis rate was 1.5-fold greater in SBM after the addition of CS-oligos. Its enhancing effect was the most prominent with milk oligosaccharides and the least with casein. The results suggest the possibility of supplementing CS-oligos as a dietary intervention strategy to address iron deficiency anaemia. However, the costly enzymes would limit the possibility of implementing such a technology for commercial opportunities. The last study evaluated possible chemical depolymerisation methods. Bovine trachea CS was hydrolyzed under acid, alkaline and combined (acid and alkaline) conditions at 60°C. The combined acid- and alkaline-treated CS possessed the greatest antioxidant capacity. All chemical hydrolyzed CS samples showed greater ferritin formation compared to the blank (p < 0.05), where the greatest ferritin level was achieved by the combined treated CS. Overall, this thesis provides a research foundation for producing high-quality CS and CS-oligos from the animal sources, as an individual compound or in a food mixture, that can enhance Fe uptake in a Caco-2 cell model. It demonstrates the potential of animal CS and CS-oligos to act as a supplement with multiple bioactivities.

This dissertation covers several topics in the second-order bias and mean squared error (MSE) of quantile and expectile estimators.Chapter one presents the introduction of this dissertation. Thefinite sample theory using higher order asymptotics provides better approximations of the bias and MSE for a class of estimators. Rilstone, Srivastava and Ullah (1996) provided the second-order bias results of conditional mean regression. The goal of this dissertation is to develops analytical results on the second-order bias and MSE for quantile and expectile estimators.Chapter two develops new analytical results on the second-order bias up to order O(N^-1) and MSE up to order O(N^-2) of the conditional quantile regression estimators. First, we provide the general results on the second-order bias and MSE of conditional quantile estimators. The second-order bias result enables an improved bias correction and thus to obtain improved quantile estimation. In particular, we show that the second-order bias are much larger towards the tails of the conditional density than near the median, and therefore the benet of the second order bias correction is greater when we are interested in the deeper tail quantiles, e.g., for the study of income distribution and financial risk management. The higher order MSE result for the quantile estimation also enables us to better understand the sources of estimation uncertainty. Next, we consider three special cases of the general results, for the unconditional quantile estimation, for the conditional quantile regression with a binary covariate, and for the instrumental variable quantile regression (IVQR). For each of these special cases, we provide the second-order bias and MSE to illustrate their behavior which depends on certain parameters and distributional characteristics. The Monte Carlo simulation indicates that the bias is larger at the extreme low and high tail quantiles, and the second-order bias corrected estimator has better behavior than the uncorrected ones in both conditional and unconditional quantile regression. The second-order bias corrected estimators are numerically much closer to the true estimators of data generating processes. As the higher order bias and MSE decrease as the sample size increases or as the regression error variance decreases, the benefits of the finite sample theory are more apparent when there are larger sampling errors in estimation.Chapter three develops the second-order asymptotic properties (bias and mean squared error) of the asymmetric least squares (ALS) or expectile estimator, extending the second-order asymptotic results for the symmetric least squares (LS) estimators of Rilstone, Srivastava and Ullah (1996). The LS gives the mean regression function while the ALS gives the "expectile" regression function, a generalization of the usual regression function. The second-order bias result enables an improved bias correction and thus to obtain improved ALS estimation. In particular, we show that the second-order bias is much larger as the asymmetry is stronger, and therefore the benet of the second-order bias correction is greater when we are interested in extreme expectiles which are used as a risk measure in financial economics. The higher order MSE result for the ALS estimation also enables us to better understand the sources of estimation uncertainty. The Monte Carlo simulation confirms the benefits of the second-order asymptotic theory and indicates that the second-order bias is larger at the extreme low and high expectiles, and the second-order bias correction improves the ALS estimator in bias.Chapter four introduces the predictive quantile regression and predictive expectile regression. Predictive regression is a fundamental econometric model and widely discussed in finance literature. This chapter focuses on the second-order bias reduction for both regression models, which enable us to obtain a better predictive estimates. An empirical application to stock return prediction using the dividend yield illustrates the benet of the proposed second-order bias reduction method. We show that the bias is larger at the tails of the stock return distribution.Chapter five contains the conclusion.

Abstract: Spent hen is a long existing issue of the poultry industry. The purpose of this study was to find alternative uses of spent hen proteins. Spent hen proteins were first extracted by pH-shifting process; the acid-aided extraction showed higher protein recovery than that of alkaline-aided extraction. Protein isolates underwent significant structural changes during freezing storage, especially for the acid-extracted proteins. Acid-extracted proteins had inferior structure stability and gelation ability than that of alkaline-extracted proteins, due to protein degradation during acid extraction and oxidation during freezing storage. Adding cryoprotectants (CP) however improved stability during storage. Adhesives prepared from acid extracted proteins without CP displayed lower viscosity, but higher adhesive strength than those of alkaline extracted proteins and proteins with CP addition during storage. Our study suggested acid-extracted proteins stored without CP addition exposed more reactive COO- groups and formed new hydrogen bonds after curing, leading to improved adhesive performance.