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This thesis reports an exploratory and contrastive corpus study examining two phenomena in postgraduate academic writing: expressing commitment/detachment and signalling authorial presence in dissertations. More specifically, the overall purpose of the study is to investigate how postgraduate academic writers from particular contexts build their academic stance and voice by employing a range of linguistic items that could be identified as hedges, boosters and authorial references. The corpus consists of a total of 90 discussions sections of master’s dissertations, 30 from Turkish L1 writers, 30 from Turkish writers of English and 30 from UK English L1 writers. A range of items, discourse functions and roles were determined during the pilot study via Nvivo 9. Then, the whole corpus was searched and analysed via WordSmith 5.0 based on the linguistic item list signalling certainty/doubt or authorial presence. In order to address two crucial phenomena in dissertation writing of postgraduates represented by three groups, both quantitative and qualitative approaches were adapted. Three key findings are as follows: 1. The postgraduates polarised: they either frequently qualified their level of commitment or else they seemingly intentionally withheld their commitment from what they asserted. The tone of writing adopted by the Turkish L1 writers differed markedly from that of the English L1 & L2 writers, as evidenced by their use of linguistic signalling expressions; the English L1 and L2 writers preferred to sound more detached from their knowledge claims, compared with the Turkish L1 writers. Therefore, the findings emphasise the importance of the language factor in expressing commitment-detachment across groups. 2. The authorial references included two broad categories: (1) Explicit authorial references (I and we-based pronouns); (2) Implicit authorial references (passive and element-prominent constructions speaking for the author). The Turkish L1 writers and the Turkish writers of English (from Turkish culture) appeared to construct less personal academic prose compared with the English L1 writers. This seems to reflect a broader cultural difference. 3. In terms of the authorial roles identified in relation to the accompanying verbs, the postgraduate writers tended to appear in their discourse most frequently as (1) Research Conductor, followed by (2) Discourse Creator & Participant; then (3) Opinion Holder. The rhetorical role indicating the membership of the postgraduates to a community (either academic or institutional), (4) Community-self, was the least frequent role adopted by the postgraduates in their discussion sections. It is recommended that, in order to raise postgraduates’ awareness about the writing conventions and practices in their disciplines, they should be provided with the standards required with respect to style via modelling from previous successful dissertations completed in their field. This is suggested as particularly important for ‘novice’ writers.

In Chapter 1, we discuss the structure of non-Euclidean Crystallographic (NEC, for short) groups and calculate the parabolic class number of Γo(N) by using a number theoretical method. We mention the modular group Γ and the extended modular group hat Γ, give two kinds of modular subgroups, mainly Γ(N) and Γo(N) and their extensions by the involution T(z) = -=z. We endow the quotient space U^*/Γo(N) with a topological structure so that U^*/Γo(N) is a compact Riemann surface. By introducing the idea of commensurability of groups, we conclude that U^*/Λ is compact if Γo(N) and Λ are commensurable. In Chapter 2, the normalizer ΓB(N) of Γo(N) in PSL(2,R) is discussed. The property of an integer h is given. Then we find the order of the quotient group B(N) = ΓB(N)/Γo(N) and in two different ways we show that B(N) is generated by the Atkin-Lehner involutions W(N) and a special matrix s. We introduce the special cusps of Γo(N) and then find their number. Next, we conclude that B(N) acts on the special cusps and from this result /B(N)/ is determined. Furthermore, the structures of B(P^α) are given for prime powers p^α. Finally we find the structure of B(N) in general and give the necessary and sufficient conditions for B(N) to be a direct product of its subgroups. In Chapter 3, we find the parabolic class number π(N) of the normalizer ΓB(N), where N is any positive integer, and we give the necessary and sufficient conditions for π(N) to be one. We also find the signature of ΓB(N), where N ≤ 50, and all possible triangle groups ΓB(N). Finally in Chapter 4, the boundary components of three kinds of NEC groups, mainly hat Γ(N), hat Γo(N) and ΓF(N) are investigated by using the Hoare-Uzzel theorem and the fixed point set F(T) of T where T(z) will be -=z or 1 over Nbar z, where N will be any positive integer except for the group ΓF(N) where N will be a square.

Stroke is the largest cause of long-term disability in U.S. where majority of the survivors experience impairments such as muscle weakness, spasticity and abnormal coordination. Stiff-Knee gait (SKG) is an incessant disability defined by the reduced knee flexion during swing. The abnormal neuromuscular mechanisms governing the interactions between impairments during SKG is still not clear. This work attempts to reveal the causal relationship between the specific influences of different impairments on post-stroke gait. Specifically, it delineates the underlying neuromuscular mechanisms behind observed increased hip abduction in SKG. The results indicate that hip abduction is part of an abnormal coordination pattern, instead of a presumed compensation for reduced knee flexion. This result is supported by previous work observing coupled knee flexion and hip abduction motions during SKG following pre-swing knee flexion torque perturbations. I hypothesized the underlying mechanism behind excessive hip abduction is due to an involuntary mechanism between quadriceps and abductor muscles which is initiated by quadriceps hyperreflexia. The results obtained from neuromusculoskeletal modeling and simulation suggest an involuntary coupled response between estimated rectus femoris (RF) and gluteus medius (GMed) activations following simulated peak RF fiber stretch velocity, suggesting an abnormal cross-planar reflex coupling initiated by excessive RF stretch reflex response. We have elicited RF reflex responses in SKG to identify the association between RF hyperreflexia and severity of the SKG excluding the influence of increased voluntary RF activity. Our results indicate a strong negative correlation between RF H-reflex response and reduced peak knee flexion angle in SKG, revealing the distinctive influence of spasticity in SKG. This novel framework delineates the abnormal neuromuscular mechanisms behind the excessive hip abduction in post-stroke gait using biomechanics, neuromusculoskeletal simulations and neurophysiological perturbations. The results obtained from this dissertation could improve lower-limb interventions for gait rehabilitation following stroke by introducing quantified measures of abnormal coordination in SKG and improve the development of subject-specific assistive technology targeting impairments to restore healthy gait.

Agent-based (AB) and system dynamics (SD) modeling and simulation techniques have been studied and used by various research fields. After the new hybrid modeling field emerged, the combination of these techniques started getting attention in the late 1990's. Applications of using agent-based (AB) and system dynamics (SD) hybrid models for simulating systems have been demonstrated in the literature. However, majority of the work on the domain includes system specific approaches where the models from two techniques are integrated after being independently developed. Existing work on creating an implicit and universal approach is limited to conceptual modeling and structure design. This dissertation proposes an approach for generating AB-SD hybrid models of systems by using Systems Modeling Language (SysML) which can be simulated without exporting to another software platform. Although the approach is demonstrated using IBM's Rational Rhapsody it is applicable to all other SysML platforms. Furthermore, it does not require prior knowledge on agent-based or system dynamics modeling and simulation techniques and limits the use of any programming languages through the use of SysML diagram tools. The iterative modeling approach allows two-step validations, allows establishing a two-way dynamic communication between AB and SD variables and develops independent behavior models that can be reused in representing different systems. The proposed approach is demonstrated using a hypothetical population, movie theater and a real–world training management scenarios. In this setting, the work provides methods for independent behavior and system structure modeling. Finally, provides behavior models for probabilistic behavior modeling and time synchronization.

Wireless sensor and actor networks (WSANs) are distributed systems of sensor nodes and actors that are interconnected over the wireless medium. Sensor nodes collect information about the physical world and transmit the data to actors by using one-hop or multi-hop communications. Actors collect information from the sensor nodes, process the information, take decisions and react to the events. This dissertation presents contributions to the methods of routing, localization and positioning in WSANs for practical applications. We first propose a routing protocol with service differentiation for WSANs with stationary nodes. In this setting, we also adapt a sports ranking algorithm to dynamically prioritize the events in the environment depending on the collected data. We extend this routing protocol for an application, in which sensor nodes float in a river to gather observations and actors are deployed at accessible points on the coastline. We develop a method with locally acting adaptive overlay network formation to organize the network with actor areas and to collect data by using locality-preserving communication. We also present a multi-hop localization approach for enriching the information collected from the river with the estimated locations of mobile sensor nodes without using positioning adapters. As an extension to this application, we model the movements of sensor nodes by a subsurface meandering current mobility model with random surface motion. Then we adapt the introduced routing and network organization methods to model a complete primate monitoring system. A novel spatial cut-off preferential attachment model and iii center of mass concept are developed according to the characteristics of the primate groups. We also present a role determination algorithm for primates, which uses the collection of spatial-temporal relationships. We apply a similar approach to human social networks to tackle the problem of automatic generation and organization of social networks by analyzing and assessing interaction data. The introduced routing and localization protocols in this dissertation are also extended with a novel three dimensional actor positioning strategy inspired by the molecular geometry. Extensive simulations are conducted in OPNET simulation tool for the performance evaluation of the proposed protocols

In Streptococcus pyogenes, the protein SiaA (HtsA) is part of a heme uptake pathway system and involved in heme transfer from Shp to the ABC transporter. SiaA mutants, in which alanine replaces the axial histidine (H229) and methionine (M79) ligands, as well as a lysine (K61) and cysteine (C58) located near the heme propionates, are reported. Studies on a mutant of a cysteine expected to be at a distance from the propionates (C47A) are also reported. The coordination state and spin state of the selected mutants were determined via Resonance Raman studies. The pKa values of mutants ranged from 9.0 to 9.4, which were close to the pKa of the WT SiaA (9.7). The midpoint reduction potential of lysine (K61A) mutant was determined by spectroelectrochemical titration to be 61 ± 3 mV vs. SHE, similar to the WT protein (68 ± 3 mV). The addition of guanidinium hydrochloride resulted in protein denaturation that could show more than one process and occurred over days. The ease of protein unfolding was directly related to the extent of interaction of the residues with the heme: changes in the axial ligands resulted in far greater changes in heme protein stability than changes in the residues near the heme propionates. The causative agent of diphtheriae, Corynebacterium diphtheriae, imports heme via an ABC uptake transporter. In this research, two of the five proteins in the heme uptake pathway of C. diphtheriae were studied. These proteins were HmuT, lipoprotein component of the ABC transporter, and HtaA, the heme receptor. UV-visible spectroscopy and fluorescence spectroscopy showed that HmuT protein as isolated bound a porphyrin, rather than heme. Electrospray ionization mass spectrometry (ESI-MS) studies suggested that two tetrapyrroles were bound. To assess stability of this protein towards heme release, thermal denaturation studies were performed. For HtaA, UV-visible and fluorescence spectroscopy also showed the protein as isolated was also bound a porphyrin, rather than heme. Homology studies showed that HtaA protein is quiet distant from homologous heme uptake proteins and could be a member of novel heme binding domain family.

Female trafficking has become a global problem affecting almost every region across the world. The crime is devastating to victims as well as communities and nations. As female trafficking increased, the United States and European countries began cooperating to reduce the crime. These efforts focus on arranging legal frameworks to punish offenders and protect victims. Despite these efforts, female trafficking is a growing problem worldwide, indicating that focusing solely on punishing traffickers and helping victims is not sufficient. The main purpose of this study is to explore how situational crime prevention can be used to prevent human trafficking. The underlying theme of situational crime prevention is that immediate features of physical and social environments create opportunities for offenders to commit crimes. Crime prevention by opportunity reduction reduces crimes by manipulating offenders’ perceived risks, efforts, and excuses. The study is designed to explore situational characteristics of female trafficking in Turkey that facilitate this crime. The study also investigates possible measures to eliminate female trafficking by altering these characteristics. The study is based on the analysis of two types of data: (a) personal interviews with representatives of nongovernmental organizations and police officials from various city police departments in Turkey and (b) a secondary data analysis of victim interviews.