Many important therapeutic agents are associated with significant undesired side effects which often limit treatment duration and dosing. Specifically, most major classes of antitumor chemotherapeutics have deleterious effects on cell division and DNA synthesis throughout the body due to systemic biodistribution. Engineering systems for controlled drug delivery allows for improved quality of life during treatment; as well as higher localized therapeutic concentrations by isolating toxic drugs used in many diseases to specific physiological compartments. An important drug delivery strategy for controlled release of therapeutics is based on responsive polymer matrices, which undergo swelling transitions in response to environmental stimuli. Biologically relevant factors which may trigger the release of therapeutics from responsive polymers include pH, ionic strength, and temperature. Temperature responsive polymers integrated into a composite system with metal nanoparticles allow for on demand drug release via an externally-applied optical or magnetic energy source. The intent of this work was to develop a temperature-responsive drug delivery platform for controlled therapeutic release, as well to expand the toolbox for rational design of responsive hydrogel nanoparticles intended for therapeutic delivery. Temperature-responsive hydrogels were synthesized and examined in the form of nanoparticles and bulk polymer networks. These materials are based on interpenetrating polymer networks (IPNs) of polyacrylamide (PAAm) and poly(acrylic acid) (PAA), which exhibit a positive volume swelling response with respect to temperature. Since this system responds to pH, ionic strength, and temperature, these IPNs were characterized over a wide range of solution conditions. Critical synthesis parameters needed to optimize thermal responses for specific solution conditions were identified, as were the specific effects of pH and ionic strength on network swelling and stability. The reverse emulsion process used to synthesize IPN nanoparticles was characterized to determine how particle growth proceeds during preparation. To enhance biocompatibility, IPN nanoparticles were surface-modified with a corona of poly(ethylene glycol) to reduce protein adsorption, a common strategy to improve in vivo performance. Due to the large amounts of surfactants employed in the preparation of IPN nanoparticles, purification methods needed to improve safety of IPN nanoparticles were optimized, and studied in vitro to ensure cellular compatibility. / text

Localized drug delivery is emerging as an effective technique due to its ability to administer therapeutic concentrations and controlled release of drugs to cancer sites in the body. It also prevents the contact of harsh chemotherapy drugs to healthy regions in the body that otherwise would become exposed to current treatments. This study reports on a model chemotherapy drug delivery system comprising non-ionic surfactant vesicles (niosomes) packaged within a temperature-sensitive chitosan network. This smart packaging, or package-within-a package system, provides two distinct advantages. First, the gel prevents circulation of the niosomes and maintains delivery in the vicinity of a tumor. Secondly, the chitosan network protects the niosomes against fluctuations in tonicity, which affects delivery rates. Tonicity is the sum of the concentrations of the solutes which have the capacity to exert an osmotic force across the membrane. Release rates were monitored from both bare niosomes alone and niosome-embedded, chitosan networks. It was observed that chitosan networks prolonged delivery from 100 hours to 55 days in low ionic strength environment and pH conditions similar to a tumor site. The primary effect of chitosan is to add control on release time and dosage, and stabilize the niosomes through a high ionic strength surrounding that prevents uncontrolled bursting of the niosomes. Secondary factors include cross-link density of the chitosan network, molecular weight of the individual chitosan polymers, dye concentration within the niosomes, and the number density of niosomes packaged within the chitosan network. Each of these factors can be altered to fine-tune release rates. Release rate experiments were conducted with 5,6-carboxyfluorescein, a fluorescent dye and chemotherapeutics paclitaxel and carboplatin. In vitro studies showed a preferential affinity of the smart packaged system to ovarian carcinoma cell line OV2008 as compared to normal epithelial cell lines of Ilow and MCC3. Further, feasibility of the drug delivery system was evaluated in vivo. Toxicity studies revealed that the system was non-toxic and feasible in vivo. The final outcome of this study includes tuning of the variables mentioned above that will contribute to the development of low cost and improved methods for drug delivery with application to intracavitary ovarian cancer treatment and other types of cancer

In the dominant management discourse, managers and consultants are credited with the ability to move their organisation in a planned, controlled way towards an idealised future. The assumptions underpinning this discourse include the following: organisations are thought of as systems that can be designed and steered in an intended direction; culture is seen as a control system to align employees’ conduct in support of the organisation’s strategy; consultants are viewed as experts in designing and implementing effective and efficient interventions, being on top of the process. These assumptions are grounded in the natural sciences of certainty, in which rational, formative and linear causality are presumed. I argue in this thesis, through a reflexive enquiry of my own practice, that these assumptions do not sufficiently resonate with my experience as an internal consultant on leadership and culture change. I am offering a critique of the dominant way of understanding organisations, culture and control, with the implication of coming to reappraise the involvement of a consultant in processes of culture change. In understanding organisations to be self-organising patterns of human interaction, culture is a social phenomenon, as it continually emerges as social control in the day-to-day local interactions of people making sense of experience. Using webs of significance, present in one’s personal history and in society, people interpret and give order to their life as they negotiate and evaluate their engagements together. In their engagement, participants will negotiate how to functionalise general values in particular situations that involve differences and can cause anxiety or even conflict. In this process of negotiation and evaluation, they are forming and being formed by each other. In this interaction no one is in control, determining in a predictable way what will happen. The participants have an influence that impacts on potential next steps in their interaction. An internal consultant’s involvement is in facilitating these processes of local interaction, enabling participants to have the conversations they tend not to have themselves, perhaps due to the anxiety of the interaction being unpredictable and predictable at the same time while no one is in control of the process or the outcome. A consultant is, as fellow participant, involved in the interaction while forming and being formed by it. He is at the same time detached: by inviting participants to work with and reflect on their experience of engaging, he enables reflexive awareness of what they are involved in together. The internal consultant, through temporary leadership, facilitates the conversation by focusing on the present, and working with differences, allowing the potential for novelty and change to occur. This temporary leadership is not a designated role or the authority of being the expert, but emerges in social interaction, through recognition and acceptance of participants acknowledging the consultant as leader in having a stronger influence than others. I propose that this alternative perspective does not offer a set of techniques, a causal framework to improve organisations in an intended and controlled way, as supposed in the dominant discourse. Rather, the perspective of complex responsive processes of relating enables a better understanding of human interaction processes; of culture emerging as social control and consulting as a social process, within the paradoxes of predictability and unpredictability, of being and not being in control, and of stability and change at the same time. It requires an internal consultant to assume a form of temporary leadership by enabling participants, through reflexive understanding of their experience, to be responsible in a critically aware manner of the ways in which they influence the next steps of engaging.

Research over the last three decades has documented that teacher efficacy has an effect on student achievement (Armor et al., 1976; Bandura, 1997). The literature on culturally responsive teaching (CRT) recognizes teacher efficacy as one of the attributes of successful teachers of students from culturally and linguistically diverse (CLD) backgrounds (Gay, 2000; Ladson-Billings, 1994). Researchers (e.g., Goddard & Goddard, 2001) have also found that collective teacher efficacy (CTE) beliefs can affect teachers’ goal setting, motivation, and persistence with challenging tasks or situations; specifically, the CTE construct not only explains school-level effects on achievement, but also explains effects on individual teachers’ self-efficacy. When CLD students require special education services, their instruction must be equally responsive to their cultural and linguistic characteristics in addition to their educational needs based on the disability (García & Ortiz, 2004; McCray & García, 2002). Consequently, CRT practices are central to improve these students’ learning outcomes (Gay, 2000). The purpose of this descriptive, correlational survey research study was to investigate (a) the relationship between special education teachers’ collective teacher efficacy beliefs and CRT efficacy for teaching CLD students in special education; and (b) the influences of personal and professional background variables on participating teachers’ CRT efficacy beliefs. The survey was sent to 855 special education teachers of CLD students with disabilities in three urban school districts in Texas; 344 complete responses were received, yielding a 44% response rate. The survey consisted of four sections: Background Information, Collective Teacher Efficacy (CTE), Culturally Responsive Teaching Self-Efficacy Scale (CRTSE), and Culturally Responsive Teaching Outcome-Expectancy Scale (CRTOE). Data were analyzed using descriptive statistics, factor analysis, analysis of variance, and multiple regression. The results revealed statistically significant relationships (a) between CRTSE and CRTOE beliefs, with a positive and moderate association; and (b) between CTE and CRT efficacy beliefs (CRTSE as well as CRTOE), but the associations were positive and weak. Teachers’ language characteristics, instructional setting, certification in bilingual education/English as a second language, and their perceptions of the quality of their professional preparation emerged as significant influences on their CRTSE and CRTOE beliefs. Implications for teacher education and future research are presented. / text

Advances in medical treatment are leading away from generalized care towards intelligent systems or devices which can sense and respond to their environment. With these devices, the burden of monitoring and dosing for treatment can be removed from the doctor (or the patient) and be placed on the device itself. Implicit closed-loop control systems will allow the device to respond to its environment and release therapeutic agent in response to a specific stimulus. Environmentally responsive hydrogels show great promise in being incorporated in such an intelligent device, such as pH-responsive hydrogels which can swell and deswell in response to changes in the pH of the media. Thus, pH changes can be exploited for controlled and intelligent drug delivery when used in combination with these pH-responsive hydrogels. In this work, heterogeneous, thermal-redox initiated free-radical polymerizations were developed to synthesize novel pH-responsive hydrogels, microparticles, and nanogels. The specific disease of interest was type I diabetes, which requires daily doses of insulin both at a basal amount and either a postprandial or preprandial bolus in order to maintain blood glucose levels within safe limits. To allow pH-responsive hydrogels to be sensitive to glucose, glucose oxidase was incorporated which oxidizes glucose to gluconic acid. A novel inverse-emulsion polymerization method was developed for the synthesis of poly[2-(diethylaminoethyl methacrylate)-grafted-polyethylene glycol monoethyl ether monomethacrylate] (P(DEAEM-g-PEGMMA)) nanogels (100-400 nm) for intelligent insulin delivery. The new polymerization method allowed the incorporation of hydrophilic components, such as glucose oxidase and catalase, as well as PEG surface tethers of lengths 400 Da up to 2000 Da. Surface tethers successfully decreased the surface charge of the nanogels. Insulin loading and release was determined for microparticles which were able to imbibe substantial amounts of insulin from solution when swollen, entrap the insulin when collapsed, and then release the insulin in response to either a pH or glucose stimulus. / text

Polymeric biomaterials have become ubiquitous in modern medical devices. ‘Smart’ materials, materials that respond to external stimuli, have been of particular interest for biomedical applications such as drug delivery. Poly(n-isopropylacrylamide) (pNIPAAm) is the best studied thermally responsive, biocompatible, ‘smart’ polymer and has been integrated into many potential drug delivery devices; however, the architectural design of the polymer in these devices is often overlooked. My research focus was the exploration of pNIPAAm architecture for biological applications. Two new biomaterials were synthesized as a result. Architectural modification of linear pNIPAAm was used to synthesize a well-defined homopolymer pNIPAAm with a sharp transition slightly above normal body temperature under isotonic conditions. This polymer required a combination of polymerization and control techniques including controlled radical polymerization, hydrogen bond induced tacticity, and end-group manipulation. The synthesis of this polymer opened up a variety of biomedical possibilities, one of which is the use of these polymers in a novel hydrogel system. Through the use of the controlled linear pNIPAAm synthesized through chain architectural modification, hydrogels with physiological transition temperatures were also synthesized. These hydrogels showed greater shrinking properties than traditional hydrogels synthesized in the same manner and showed physiological mechanical properties. Highly branched pNIPAAm was also optimized for biological applications. In this case, the branching reduced the efficacy of end-groups in transition temperature modification but increased the efficacy of certain copolymers. The resulting biomaterial was incorporated into a nanoparticle drug delivery system. By combining gold nanoparticles with highly branched pNIPAAm, which was designed to entrap small molecule drugs, a hybrid system was synthesized where heating of the nanoparticle through surface plasmon resonance can trigger drug release from the pNIPAAm. This system proved to be easy to synthesize, effective in loading, and controlled in release. As shown from the applications, architectural control of pNIPAAm can open up new possibilities with this polymer for biomedical applications. Small structural changes can lead to significant changes in the bulk properties of the polymer and should be considered in future pNIPAAm based medical devices.

This study explored the racial identity development of White corporate trainers who deliver training in racially diverse organizations. The purpose of this study was to acquire an understanding about the various factors that affect the racial identity development of White trainers as well as to distinguish ways in which racially diverse organizations support the creation of culturally responsive training. The study sought to identify aspects that affect White trainers’ identity and the role of the organizations in defining, or impacting, competencies related to culturally responsive training. A basic qualitative design guided the study and data was collected through two face-to-face interviews and a written reflection in response to their own completed interview transcripts. The participants included six White females and one male and were employed in organizations in the areas of oil and gas, real estate, retail, and consulting. The participants were identified by their connection to Texas A&M University students and faculty, the Academy of Human Resource Development, or the American Society for Training and Development. The findings of the study indicated that White corporate trainers develop their racial identity through a variety of experiences in their personal and professional environments. The White trainers’ perceptions of racial identity were impacted through environmental influences and their construction of Whiteness. Their racial consciousness was further developed through their work within racially diverse organizations and cultural diversity within the training environment exposed the trainers to their weaknesses and areas for growth. The process of becoming more culturally responsive trainers was a constant evolution that took place through self-reflection and the acknowledgment of race as an important component related to identity and their work.

In my study, I have chosen to examine how the user interface and content must conform to design guidelines for responsive design makes it suitable for diverse desktop environment and for varied mobile platforms. The purpose of this study is to examine the extent recommended design guidelines based on scientific research has a positive impact on user performance and perception when using this study delivered hi-fi prototype. The goal of this study is to provide a Hi-Fi prototype with high usability that will introduce and inform the public about BrasilCine according specifications. Study findings from user testing and supplementary questionnaires show that the implemented technologies as design guidelines for responsive design and design features have a positive impact on user performance and perception. The study results are therefore relevant for further prototype development.

Self-folding polymer films were only recently proposed as an alternative method for the design of three-dimensional constructs. Due to the relative novelty of the approach, insufficient amount of data on the behavior of such systems is available in the literature. This study is bound to fill the gaps and give a deeper insight into the understanding of how and why different types of folding occur. In this study, four different types of folding of polymer bilayers are presented. Rectangles are one of the simplest geometrical forms and were therefore adopted as a convenient initial system for the investigation of the folding behavior of polymer bilayers. We chose PNIPAM for the active polymer, as it is a well-studied polymer with sharp Lower Critical Transition Temperature at around 33 C. For the passive layer, poly(methyl methacrylate) and poly(caprolactone) were chosen. The influence of different parameters of the system, such as polymer thickness and temperature was thoroughly investigated in order to be accounted for in later experiments. It was demonstrated that bilayers placed on a substrate start to roll from the corners due to quicker diffusion of water. Rolling from the long-side starts later but dominates at high aspect ratio. We showed that the main reasons causing a variety of rolling scenarios are (i) non-homogenous swelling due to slow diffusion of water in hydrogels and (ii) adhesion of polymer to a substrate until a certain threshold. Moreover, non-homogenous swelling determines folding in the first moments, while adhesion plays a decisive role at later stages of folding. After having understood the abovementioned basics, we decided to explore how those applied to more complex shapes. For the purpose, four- and six-arm stars were chosen, the main idea behind this being the creation of self-folding polymer capsules capable of encapsulation of microparticles and cells. Adjusting the polymer thickness and thus the radius of folding allowed creating structures, capable of reversible self-folding and unfolding. The possibility to reversibly encapsulate and release objects in the micro-range was demonstrated on the example of yeast cells. Noteworthy, the capsules were produced by means of the same process we used for the design of tubes – when compared to the folding of rectangles, it was the shape of the initial pattern and the folding radius that were changed; the mechanism was the same – simple one-step folding towards the center of the bilayer. Clearly the number of structures that can be generated by this method is fairly limited. The search for means to overcome this constraint led to the idea of hierarchical multi-step folding. Due to the edge-activation of the bilayers, the observed deformed shapes differ from the classical ones obtained by homogeneous activation. It was found that films could demonstrate several kinds of actuation behavior such as wrinkling, bending and folding that result in a variety of shapes. It was demonstrated that one can introduce hinges into the folded structure by proper design of the bilayer's external shape through diffusion without having to use site selective deposition of active polymers. Experimental observations led us to derive four empirical rules: 1) “Bilayer polymer films placed on a substrate start to fold from their periphery and the number of formed wrinkles/tubes decreases until the angle between adjacent wrinkles/tubes approaches 130°”; 2) “After the wrinkles along the perimeter of the film form tubes, further folding proceeds along the lines connecting the vertexes of the folded film”; 3) “The folding goes along the lines which are closer to the periphery of the films”; 4) „Folding of the rays may result in blocking of the neighboring rays if the angle between the base of the folded ray and the shoulders of the neighboring rays is close to 180°”. These rules were then applied to direct the folding of edge-activated polymer bilayers through a concrete example - the design of a 3D pyramid. One consequence of the second and third rules is that generally triangles are formed during the multi-step folding process. In order to create a cube, or any other 3D structure with non-triangular sides, an effective way to stop the folding along the lines, connecting neighboring vertexes had to be thought of. A possible solution would be the insertion of a rigid element inside the bilayer, perpendicular to the direction of folding. The solution of this problem was to design structures with pores. A pore would normally decrease the rigidity of a structure but in our case, a pore basically comprised an edge inside the structure and could thus form tubes which, as was already shown, exhibit much higher rigidity than a film. On the other hand, a pore, or many pores, would expose different parts of the active layer to the solvent and would strongly influence its swelling and, as a consequence, folding behavior. Hence, the influence of a pore on the swelling and the folding behavior of polymer bilayers had to be investigated. It was shown that pores of the right form and dimensions did indeed hinder the folding as intended. Instead, the polymer films took other ways to fold. As a result, despite the correctness of our reasoning, we failed to produce a cube by hierarchical folding of polymer bilayers. However, other sophisticated 3D objects were obtained, further increasing the arsenal of available structures, as well as giving an in-depth insight on the folding process.

Teen pregnancy in New Zealand has been constructed as a multifaceted problem, which has prompted scrutiny into the lives of pregnant and parenting teens and their children. Research largely presents teen mothers as ‘at risk’ parents and high school drop outs, with high rates of welfare dependence. Teen parents are considered unlikely to achieve the educational and economic success of their non-parenting peers. This research considers the impact of the experience at a Teen Parent Unit (TPU) on the ways pregnant and parenting teens understand and achieve success. Using a qualitative case study of a Teen Parent Unit in an urban setting in New Zealand, this thesis documents the experiences and perspectives of four young women. Its aim is to detail, explain and interpret the ways these pregnant and parenting teens understand their developing identities as successful students and parents. Drawing on social constructionist perspectives, the views of the young women participants, and of the researcher have been analysed through a conceptual lens of culturally responsive pedagogical theory. Comparisons are made between the culture of success that has been developed in the Teen Parent Unit setting and that of schools which have engaged in Māori culturally responsive pedagogical practice. This thesis offers a strengths-based analysis of an environment which, by reframing expectations of success, presents a challenge to negative academic and societal expectations of pregnant and parenting teens. Its goal is to provide educators, social support agencies, education and social policy makers with an analysis of approaches that have made important differences in the lives of the young women and their children.