This thesis investigated a new group of poly(Bd)/poly(Bd-co-MAA) core-shell particles that were ionically crosslinked and cast as nanostructured ionomer films from aqueous dispersions. The new group of poly(Bd)/poly(Bd-co-MAA) core-shell particles were studied for structure-property relationships and morphology. The covalent crosslinking content in the core and the shell were varied at constant ionic crosslinking. Stress-strain data showed control of the nanostructured films. The chain transfer agent used during the preparation of the nanoparticles core-shells was shown to independently tune the mechanical properties of the films.

Stimuli-responsive polymers and self-assembling peptides represent two classes of materials with interesting properties and great potential to be used as biomaterials. The conjugation of polymer with peptide offers a way to combine the controlled chemical, mechanical, and thermal properties of polymer with the functionality of designed bioactive group. Pure hybrid materials with the characteristics of individual components or systems containing hybrid materials became attractive for applications in drug delivery and tissue engineering. This work focused on systems where the thermo-responsive properties of a polymer were combined with the gelling properties of two different ionic-complementary peptides via conjugation. The prototypical thermo-responsive polymer poly(N-isopropylacrylamide) (PNIPAAm) was chosen due to its lower critical solution temperature (LCST) ~32°C being close to body temperature. Ionic-complementary oligo-peptides, containing the alternating hydrophobic/hydrophilic and charged/uncharged amino acids, phenylalanine (F), glutamic acid (E) and lysine (K), were selected as they are known to form β-sheet rich fibrillar networks at low concentrations. Two peptide sequences with different charge distribution were chosen: FEFEFKFK and FEFKFEFK which form self-supporting gels at ~17 and 10 mg ml-1 respectively. Polymer-peptide conjugates were used to confer self-assembling and thermo-responsive behaviour to the system.Thermo-responsive PNIPAAm-rich hydrogels were obtained by targeting different degrees of functionalisation of PNIPAAm with the self-assembling peptides. Two series of such systems were prepared by using either a thiol-modified FEFEFKFK or a thiol-modified FEFKFEFK peptide as the chain-transfer agent in the free radical polymerisation of NIPAAm. The resulting polymer/conjugate mixtures were studied by proton nuclear magnetic resonance (1H NMR). The polymer/conjugate ratios were calculated and showed that the conjugate fraction in the mixtures increased with increasing concentration of peptide used for the polymerisation. Static light scattering (SLS) and viscometry showed the aggregation of the polymer/conjugate mixtures presumably due to the presence of peptide. The values from gel permeation chromatography (GPC), which were mostly attributed to the unconjugated polymers, were higher than those obtained from 1H NMR and centrifugation for the conjugates. The polymer/conjugate mixtures formed self-supporting gels where the critical gelation concentration decreased with increasing conjugate content. Oscillatory rheology experiments confirmed gels had formed and revealed that their elastic modulus, G' varied from ~ 10 to 400 Pa depending on the sample. TEM and AFM studies proved the formation of β-sheet fibres of ~ 4.5 ± 1.5 nm in diameter. The PNIPAAm-rich hydrogels were also characterised by micro DSC to reveal their thermo-responsiveness and phase separation and showed the LCST at ~ 30°C. The results of the study showed that varying the peptide sequence did not have an effect on thermal, mechanical or morphological properties of the hydrogels. By exploiting the self-assembly of the ionic-complementary peptides, it was possible to create PNIPAAm-rich, thermo-responsive hydrogels with controllable properties.Further in the study pure PNIPAAm-FEFEFKFK conjugate was incorporated into the FEFEFKFK peptide matrix to create peptide-rich thermo-responsive composite gels. Two series of the composite gels were prepared by varying separately the peptide matrix and polymer-peptide conjugate concentration. Micro DSC measurements revealed an endothermic peak at ~ 30ºC characteristic of the LCST of PNIPAAm. Oscillatory rheology studies showed that the composite gels became stronger with increasing conjugate concentration (G' ~ 20 - 200 Pa). Network morphology was studied by SANS. Using contrast variation and contrast matching techniques it was possible to distinguish between the peptide fibres and the PNIPAAm chains. Below and above the LCST the scattering curves showed a q-1 behaviour which is typical of rod-like objects. TEM and AFM also proved the formation of fibres of ~4.0 ± 0.8 nm and ~4.5 ± 1 nm respectively. AFM studies showed that the fibres of the composite gels were decorated with polymer chains. The thermo-responsiveness and the gelation properties of these conjugate-based scaffolds have potential for use as drug delivery vehicles or tissue engineering scaffolds.

This master thesis focuses on approaches to solving mobile web applications. Author focuses on the classification of mobile devices and the description of their attributes and specifications of touch screen controls. Part of the work is devoted to the characteristics of mobile operating systems and of mobile web browsers. One chapter is aimed on the psychology of user behaviour and expectations of mobile users from mobile website. A significant part of the work is paid to specifications of the development of web design for mobile devices and the differences to classical web design. In addition, the author describes the Responsive Web Design and the idea of Mobile First. In the practical part, the author analyzes the cross platform access to websites of Czech railway transport companies -- České dráhy, LEO Express and RegioJet. The access from smartphones, tablets and desktops is tested using analysis based on multi-criteria evaluation. To test the author uses a web emulator to simulate different versions of operating systems and web browsers. The aim of the analysis is to create a series of recommendations for better optimization of access from mobile devices.

Toy play represents one of many levels of play where children can expand their repertoires and socially interact with peers. Play typically increases in complexity as the child's repertoire develops; however, children with autism often have delayed play skills. The current study investigated the effects of using a 3-component play training procedure (choices, prompting, and consequences), replicated from a previous study, to increase simple and pretend toy play in three boys with autism. Additional measures were used to observe engagement with materials, children, and adults during a 10-minute session. Observations show increased toy play for two participants and increases in overall engagement for all participants. The findings suggest that the teaching program used is replicable across multiple populations, furthering the advancement of evidence-based practices.

Les polymersomes sont des vésicules dont la membrane est formée d'une bicouche de polymères amphiphiles. Les polymersomes dits stimulables sont particulièrement étudiés de nos jours pour leurs propriétés de relargage contrôlé. Ces propriétés peuvent être ajustées simplement en variant la nature chimique du polymère constituant la membrane vésiculaire.Dans le cadre de ce travail de thèse, nous nous sommes intéressés à des polymersomes originaux, assemblés à partir de copolymères cristaux liquides. Ces copolymères comprennent un bloc cristal liquide hydrophobe et un bloc poly(ethylene glycol) (PEG) hydrophile. Les cristaux liquides sont des entités particulièrement intéressantes pour leur capacité d'auto-assemblage et leurs réponses aux stimuli physiques tels la température, les champs magnétiques et la lumière.Plusieurs types de polymersomes basés sur des copolymères cristaux liquides ont été étudiés en température et en champ magnétique. L'effet thermique est drastique, perturbant totalement la morphologie vésiculaire au dessus d’une température critique. Différents hybrides de nanoparticules d’oxyde de fer et de polymères cristaux liquides ont aussi été examinés dans le but d’induire un chauffage local par hyperthermie magnétique.Enfin, nous décrivons la synthèse de copolymères amphiphiles cristaux liquides biodégradables incluant des motifs cholesterol. L'auto-assemblage de ces molécules en milieu aqueux a permis la formation de nanoparticules bien définies et prometteuses pour des applications de relargage en milieu biologique. / Polymersomes are vesicles whose bilayer is made of amphiphilic polymers. Stimuli responsive polymersomes are nowadays increasingly studied for their encapsulation properties and ability to release their content upon stimulation. Such smart polymersomes can be designed by using appropriate responsive building blocks.In the present study, we were interested in studying thermoresponsive and biodegradable polymersomes made of liquid crystalline (LC) amphiphilic copolymers. LC polymers represent here the hydrophobic block while the hydrophilic block consists in poly(ethylene glycol) (PEG). LC polymers are very good self-assocative building blocks and are intrinsically responsive to physical stimuli such as temperature, light and magnetic fields.We report here the investigation of temperature effects on liquid crystalline and non liquid crystalline polymersomes. Temperature was shown to alter dramatically LC polymersomes morphology above a critical thermal threshold. Hybrid colloids made of iron oxide nanoparticles and amphiphilic liquid crystalline copolymers were also studied with the aim of applying a magnetically induced local heating.Finally, we designed biodegradable liquid crystalline copolymers based on cholesterol. Their self assembly in water gave access to very well defined nanoparticles that could be promising for bioapplications.

The concern for the environment and social aspects have been emphasizing in the concept of ecotourism. Tourism is the world's largest industry. "It accounts for more than 10% of total employment, 11% of global GDP, and total tourist trips are predicted to increase to 1.6 billion by 2020". As such, it has a major and increasing impact on both people and nature. The increase of travels and tourists in the world, has led to the acknowledgement of tourism as part of the emissions of greenhouse gases. Therefore, the framework of sustainable development in tourism has been developed as well as ecotourism. Eco-tourism can be both an effective conservation tool and a successful community development model. Sustainable architecture can be well integrated in a community that will base their knowledge on role model site for the sustainability of a park and village. This thesis is aiming to study and develop a sustainable model for the conflict that exists between architecture and eco-tourism because of current practices and their impact on natural habitat. Inappropriate tourism development and practice can degrade habitats and landscapes, deplete natural resources, and generate waste and pollution. The local community is also in need of a better and healthy living. This has become a social, cultural, and economical issue prevalent for decades since there hasn't been an established relationship between the local community and the tourist. The main investigation into determining factors is on how and why we need the bond between eco-village and eco-tourism. Does it consist of culture and society integration? Or is it nature preservation? What is the new relationship between tourist-community or tourist development design and development of this relationship? Some of the options for research and study is an eco-cabin that will serve as a prototype for ecotourism sustainable technologies and architecture, integrating an eco-village as a model for the local community. A way to approach this issue is through the education of the local people and tourism through sustainable architecture and development. Community knowledge can be increased through environmental sustainable building techniques. Perhaps the community gets involve in the construction process, so they learn how to take care of their surroundings and its stewardship.. In this way the sustainability of well-being of human cultures that inhibit those environments are sustained, and tourists can get engaged through community learning and interaction. Responsible tourism can also promote awareness of and support for the conservation of local culture, creating economic opportunities for countries and communities.

Thesis advisor: Martin Scanlan / While the U.S. student body is increasingly racially, ethnically, culturally, and linguistically diverse, the teaching population itself, however, does not mirror this same diversity. As such, there is an urgent need for teachers who can adequately meet the needs of an increasingly diverse student population (Sleeter, 2001). Some teachers are undeniably more successful at the task of educating diverse student populations than others. How then - are these teachers in particular - successfully able to effectively teach students across various lines of difference? The purpose of this qualitative individual study is to explore teachers’ views on how they have developed their cultural proficiency. How do teachers who have been identified by school leaders as particularly effective at teaching diverse student populations develop their culturally responsive practice, and more pointedly - their capacity to effectively teach students from historically marginalized groups (i.e. students from racially minoritized groups or socio-economically disadvantaged groups)? Utilizing a sense-making framework, and gathering information using methods including semi-structured interviews, teacher questionnaires, and reflective journaling, this study uncovers emergent themes and trends in how individual teachers within a diverse Massachusetts school district make sense of the process by which they developed their culturally responsive teaching capacities and practice. If educational leaders form a better understanding of how teachers effectively develop their cultural competencies, then principals and district leaders will be able to use this information to more effectively design professional development programs that sustain teachers’ cultural proficiency and better equip them to successfully serve the increasingly diverse student population. / Thesis (EdD) — Boston College, 2020. / Submitted to: Boston College. Lynch School of Education. / Discipline: Educational Leadership and Higher Education.

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abstract: As experiencing hot months and thermal stresses is becoming more common, chemically protective fabrics must adapt and provide protections while reducing the heat stress to the body. These concerns affect first responders, warfighters, and workers regularly surrounded by hazardous chemical agents. While adapting traditional garments with cooling devices provides one route to mitigate this issue, these cooling methods add bulk, are time limited, and may not be applicable in locations without logistical support. Here I take inspiration from nature to guide the development of smart fabrics that have high breathability, but self-seal on exposure to target chemical(s), providing a better balance between cooling and protection. Natural barrier materials were explored as a guide, focusing specifically on prickly pear cacti. These cacti have a natural waxy barrier that provides protection from dehydration and physically changes shape to modify surface wettability and water vapor transport. The results of this study provided a basis for a shape changing polymer to be used to respond directly to hazardous chemicals, swelling to contain the agent. To create a stimuli responsive material, a novel superabsorbent polymer was synthesized, based on acrylamide chemistry. The polymer was tested for swelling properties in a wide range of organic liquids and found to highly swell in moderately polar organic liquids. To help predict swelling in untested liquids, the swelling of multiple test liquids were compared with their thermodynamic properties to observe trends. As the smart fabric needs to remain breathable to allow evaporative cooling, while retaining functionality when soaked with sweat, absorption of water, as well as that of an absorbing liquid in the presence of water were tested. Micron sized particles of the developed polymer were deposited on a plastic mesh with pore size and open area similar to common clothing fabric to establish the proof of concept of using a breathable barrier to provide chemical protection. The polymer coated mesh showed minimal additional resistance to water vapor transport, relative to the mesh alone, but blocked more than 99% of a xylene aerosol from penetrating the barrier. / Dissertation/Thesis / Doctoral Dissertation Chemical Engineering 2020

The rapidly expanding of the global population in the 21st-century forces people facing two serious problems: water scarcity and energy shortage. Enormous continuous studies focus on providing enough fresh water and energy in a sustainable way. This thesis aims at exploring novel membrane processes based on thermally responsive ionic liquids with the upper critical solution temperature (UCST ILs) for water desalination and energy conversion from low-grade heat energy to electricity. A UCST IL protonated betaine bis(trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) was first experimentally studied as a novel draw solute in a thermal forward osmosis (FO). A 3.2 M [Hbet][Tf2N] solution can be obtained via spontaneous phase separation from an IL and water mixture at room temperature. By heating and maintaining the temperature above 56°C, this solution can draw water from high-salinity solution up to 3.0 M, 5 times salty as the sea water. The IL draw solution can be easily regenerated by phase separation. Conducting the FO process at higher temperatures can also increase the water flux. According to the different choices of the freshwater polishing step, the electric energy consumption in this novel process was estimated as 26.3% to 64.2% of conventional one-step sea water reverse osmosis. Two UCST ILs with better performance, [Hbet][Tf2N] and choline bis(trifluoromethylsulfonyl)imide ([Choline][Tf2N]), were selected as the agents in a novel closed-loop thermally responsive IL osmotic heat engine (TRIL-OHE) to convert low-grade thermal energy to electricity. The specific energies of the [Hbet][Tf2N] system and the [Choline][Tf2N] system are 2500 kJ/t and 3700 kJ/t, which are 2.7 and 4.0 times of the seawater and river water system, respectively. The maximum power density measured from a commercial FO membrane is 1.5 W/m2 for the [Hbet][Tf2N] system and 2.3 W/m2 for the [Choline][Tf2N] system, leaving a big room to improve if highly permeable membranes are used. Another notable advantage of the TRIL-OHE is the heat released from the cooling stage can be largely recovered. A rigorous energy balance showed with a 70% heat recovery, the energy efficiency could be increased from around 20% to 70% of the Carnot efficiency in both UCST ILs systems.