Disulfide bonds are special covalent cross links between two cysteines in a protein. This kind of bonding state plays an important role in protein folding and stabilization. For connectivity pattern prediction, it is a very difficult problem because of the fast growth of possible patterns with respect to the number of cysteines. In this thesis, we propose a new approach to address this problem. The method is based on hybrid models with SVM. Via this strategy, we can improve the prediction accuracies by selecting appropriate models. In order to evaluate the performance of our method, we apply the method by 4-fold cross-validation on SP39 dataset, which contains 446 proteins. We achieve accuracies with 70.8% and 65.9% for pair-wise and pattern-wise prediction respectively, which is better than the previous works.

In this study we synthesized poly(tyrosine) (PTyr) through living ring-opening polymerization of £\-amino acid-N-carboxyanhydride and then blended with poly(4-vinyl pyridine) (P4VP) homopolymer in N, N-dimethylformamide (DMF) and methanol solutions to control the miscibility behavior and the secondary structures of poly(tyrosine). Infrared spectrum analysis suggests that the mixture of PTyr/P4VP possesses strong hydrogen-bonding interaction between the hydroxyl group of PTyr and the pyridine group of P4VP. DSC analyses indicate that these PTyr/P4VP complexes from methanol solution always have higher glass transition temperatures than the corresponding PTyr/P4VP miscible blends obtained from DMF solution. We proposed that the polymer chain behavior of PTyr/P4VP blend from DMF solution is the separated random coil and thus the PTyr chain possesses the random coil secondary structure after solvent evaporation. However, by increasing the hydrogen bonding for PTyr/P4VP complex from methanol solution, inter-polymer complex aggregate is proposed and the corresponding chain behavior enhances the intermolecular hydrogen bonding interaction of PTyr with P4VP that results in the £]-sheet conformation based on Fourier transforms infrared (FTIR), solid state nuclear magnetic resonance (NMR) spectroscopy, and wide-angle X-ray diffraction analyses.

Credit risk of derivative securities includes the risk of underlying company and the risk of seller's nonfulfilment of contracts. Take bonds for example, we regard Treasury bills as default-free bonds, and corporate bonds as risky bonds. When the liability of property of derivative securities underlying company is less than 1, we regard the company is of bankruptcy. And then the seller of derivative securities will break the contract. The essay extends two period risky bonds pricing valuation of Jarrow and Turnbull(1995) to multiperiod situation, and derive arbitrage-free condition. Furthermore, we derive formulae of risky bonds prices by assuming the logarithm of the odds ratio of an underlying company's bankruptcy probability satisfies an AR(1) or MA(1) processes. Empirical data of Rebar, Chinarebar, Ceon are studied, time series models are established for logarithm of odds ratios. In most cases, we find that the log odds ratios can be well fitted by AR(1) models.

The objects this thesis want to study can be separated into two parts. The first part is investigating why firms choose to issue convertible bond. We use the public financial information and macroeconomics factors to establish a security choice model. In this security choice model, we can understand the motivation of issuance and investors¡¦ expectation of security type (equity-like or debt-like) which will be issued. The second part of this thesis is about convertible bond issuance announcement effect. We want to know if the public information and the pre-issuance security type expectation would affect the announcement effect. Following is the conclusions: (1) We find that less information asymmetry, less agency cost, more operating risk will lead to higher probability of equity-like security issuance. (2) Most convertible bonds issued in Taiwan are more debt-like. (3) Equity-like convertible bonds issuances have negative announcement effect. The issuances different from expectation will lead to more negative price effect, especially those debt-like firm but issue equity-like security. (4) The variables that can explain security choice may not explain the announcement price effect.

The purpose of this study was to examine the use and effect of figurative language discourse in examples of expert therapy. More specifically, one of the main reasons for conducting this study was to describe figurative language discourse, its production, use, and potential effects on the therapeutic relationship and client experiencing. Training videos were selected and transcribed using criteria for selection of examples of expert therapy. Fifty-six excerpts, each two-minutes in length, were taken from the transcribed therapy sessions and used for the analyses. One set of raters was trained to identify instances of figurative language and make ratings of shared theme. Another set of raters was trained to use the Experiencing Scales and the Working Alliance Inventory on the transcribed excerpts. Analyses were conducted to investigate the frequency of use and relationship between therapist and client figurative language dialogue. Results indicated that the majority of figurative language used in examples of expert therapy is metaphoric in nature. Additionally, it was found that the majority of figures of speech were frozen in meaning or were commonly used. A small percentage of figures of speech were shared conceptually between the therapist and the client. Regarding the shared figurative language, a statistically significant difference between therapists and clients with regard to their production of shared figurative language was found and indicates that use of shared figurative language by expert therapists may be a subtle and indirect way in which therapeutic alliance is initially established as well as maintained. It may also represent how expert therapists follow content of the therapy session. In addition, a regression analysis conducted to determine if there is a relationship between shared figurative language and ratings of therapeutic alliance did not meet statistical significance. Overall, the results of this study provide preliminary findings with regard to what type of figures of speech expert therapists use and give a clear direction in terms of the next direction for research. Additionally, this experiment provides direction for the type of methodology that should be utilized in future research.

The rational choice theory provides good explanations of the factors on juvenile delinquency: the decision-making mechanism of delinquency is as same as the other activities, is based on the rationality. Juveniles will increase the probability of delinquency if the expected utility exceeds the expected cost; oppositely, they will reduce the probability of delinquency if the expected cost exceeds the expected utility. This proposed research from the perspective of rational choice is to study the influence between juveniles¡¦ individual rationality and delinquency and intend to provide the reasonable explanation to provide the reasonable explanation to juvenile delinquency. But besides individual rational choice factor, the degree of social bond will also have the influence to juvenile delinquency, therefore this research will also simultaneously discuss the mediate effects of the society bonds to the rational choice and juvenile delinquency. Our results suggest that the rational choice (perception of risks and self-imposed costs) and the social bonds (attachment and belief) are negatively related to juvenile delinquency. The society bonds (attachment and belief) could mediate the effects of the rational choice and juvenile delinquency. The interaction between demographic characteristics and rational choice has few effect on juvenile delinquency.

Disulfide bond information can help the prediction of protein secondary structure, tertiary structure and all-atom coordinates. Most of previous works focused on either state classification or connectivity prediction with some assumption that some constraints were added to make the problem solvable in reality. In this thesis, we propose a multi-phase approach to solve the problem. Our method can export the number of bonds and achieve 90.7% accuracy in the state classification. For the connectivity prediction problem, we use the number of bonds we predict as a base to decide bond pairs. For overcoming the ratio imbalance of samples, we propose a down-sampling method to reducing processing time. Finally, we perform the weighted graph matching algorithm to obtain the bonding pattern, which achieves 63.5% accuracy. We also achieve 48% accuracy for the thorough prediction. Our method is validated by the datasets derived from SWISS-PROT and PDB. The results are better than the previous works.

Differential scanning calorimetry (DSC), 13C solid state nuclear magnetic resonance (SSNMR), one- and two-dimensional fourier transform infrared spectroscopes (FT-IR), Gel Permeation Chromatography (GPC) have been used to investigate the miscibility behavior and specific interactions of Poly(3-hydroxybutyrate), (PHB) blending with poly(styrene-co-vinyl phenol), (PS-co-PVPh) through hydrogen bonding complex upon varying the vinyl phenol contents in copolymer. We describe FT-IR spectra reveal that hydrogen bonding between carbonyl and phenol. A miscibility window exists when the vinyl phenol fraction in the copolymer is greater than 20 mol% in the PHB/PS-co-PVPh blend system, as predicted using the Painter¡VColeman association model. The vinyl-terminated benzoxazine (VB-a), which can be polymerized through ring opening polymerization, was synthesized through the Mannich condensation of bisphenol A, formaldehyde, and allylamine. This VB-a monomer was then blending with epoxy resin, followed by thermal curing concurrently, to form epoxy/VB-a copolymers network. To understand the curing kinetics of this epoxy/VB-a copolymer, dynamic differential scanning calorimetry measurements were performed by Kissinger and Flynn-Wall-Osawa methods. The FTIR analyses revealed the presence of thermal curing reactions and hydrogen bonding interaction of epoxy/VB-a copolymers. Meanwhile, the significant enhancement of the ring opening and allyl polymerizations of the epoxy was observed. For these IPNs, DMA and TGA results indicate that the thermal properties increase with the increase of VB-a contents in epoxy/VB-a copolymers.

Metal-catalyzed, hydrogenative methods for carbon-carbon bond formation are attractive alternatives to traditional carbonyl addition reactions. Through in situ generation of aldehyde and organometallic species, these redox-triggered reactions circumvent the need for preactivation of reactive partners, thereby providing a more atom economic, efficient approach to carbonyl addition products. Efforts have been focused on the development of ruthenium-catalyzed coupling reactions of primary and secondary alcohols to basic feedstock chemicals and easily accessible and stable unsaturated compounds. To perform highly stereoselective reactions, investigation into the factors that control stereoselectivity in ruthenium catalyzed transfer hydrogenative couplings was undertaken. As a critical tool for the construction of organic molecules, modernizing methods for carbonyl addition can contribute to the evolution of synthetic organic methodology. / text

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