Theoretical investigations of intercellular communication in the microcirculation: Conducted responses, myoendothelial projections and endothelium derived hyperpolarizing factor

The contractile state of microcirculatory vessels is a major determinant of the blood pressure of the whole systemic circulation. Continuous bi-directional communication exists between the endothelial cells (ECs) and smooth muscle cells (SMCs) that regulates calcium (Ca2+) dynamics in these cells. This study presents theoretical approaches to understand some of the important and currently unresolved microcirculatory phenomena. ^ Agonist induced events at local sites have been shown to spread long distances in the microcirculation. We have developed a multicellular computational model by integrating detailed single EC and SMC models with gap junction and nitric oxide (NO) coupling to understand the mechanisms behind this effect. Simulations suggest that spreading vasodilation mainly occurs through Ca 2+ independent passive conduction of hyperpolarization in RMAs. Model predicts a superior role for intercellular diffusion of inositol (1,4,5)-trisphosphate (IP3) than Ca2+ in modulating the spreading response. ^ Endothelial derived signals are initiated even during vasoconstriction of stimulated SMCs by the movement of Ca2+ and/or IP3 into the EC which provide hyperpolarizing feedback to SMCs to counter the ongoing constriction. Myoendothelial projections (MPs) present in the ECs have been recently proposed to play a role in myoendothelial feedback. We have developed two models using compartmental and 2D finite element methods to examine the role of these MPs by adding a sub compartment in the EC to simulate MP with localization of intermediate conductance calcium activated potassium channels (IKCa) and IP3 receptors (IP 3R). Both models predicted IP3 mediated high Ca2+ gradients in the MP after SMC stimulation with limited global spread. This Ca 2+ transient generated a hyperpolarizing feedback of ∼ 2–3mV. ^ Endothelium derived hyperpolarizing factor (EDHF) is the dominant form of endothelial control of SMC constriction in the microcirculation. A number of factors have been proposed for the role of EDHF but no single pathway is agreed upon. We have examined the potential of myoendothelial gap junctions (MEGJs) and potassium (K+) accumulation as EDHF using two models (compartmental and 2D finite element). An extra compartment is added in SMC to simulate micro domains (MD) which have NaKα2 isoform sodium potassium pumps. Simulations predict that MEGJ coupling is much stronger in producing EDHF than alone K+ accumulation. On the contrary, K+ accumulation can alter other important parameters (EC V m, IKCa current) and inhibit its own release as well as EDHF conduction via MEGJs. The models developed in this study are essential building blocks for future models and provide important insights to the current understanding of myoendothelial feedback and EDHF.^

Gender politics, women's rights and international norms in Lebanon

The purpose of this dissertation is to investigate the reasons for the under-representation of women in politics in Lebanon, and the role of international norms of gender equality in bringing about change. For those questions, I examined the particular relevance of confessionalism arguing that a confessional social structure and political system empower patriarchal forms of organization with detrimental effects to women's political participation. This dissertation makes innovative contributions to two types of literature. First, literature on the barriers to women being elected into political office has put strong emphasis on electoral systems of representation, but has rarely addressed the way in which electoral systems that seek to ensure minority representation – such as the confessional system in Lebanon – operate to keep women out of politics. This study provides an important corrective to this literature by exploring a non-Western case and broadening theorizing on the issue. Second, constructivist literature in the field of International Relations has argued that international norms of gender equality – including gender quotas – have diffused throughout the 20th century. This research illustrates the mechanisms that counteract international diffusion, and adds to our understanding of how international norms are translated into domestic contexts.

Phylogenetic and ecological significance in the evolution of Cetacean tonal sounds

Cetaceans are aquatic mammals that rely primarily on sound for most daily tasks. A compendium of sounds is emitted for orientation, prey detection, and predator avoidance, and to communicate. Communicative sounds are among the most studied Cetacean signals, particularly those referred to as tonal sounds. Because tonal sounds have been studied especially well in social dolphins, it has been assumed these sounds evolved as a social adaptation. However, whistles have been reported in ‘solitary’ species and have been secondarily lost three times in social lineages. Clearly, therefore, it is necessary to examine closely the association, if any, between whistles and sociality instead of merely assuming it. Several hypotheses have been proposed to explain the evolutionary history of Cetacean tonal sounds. The main goal of this dissertation is to cast light on the evolutionary history of tonal sounds by testing these hypotheses by combining comparative phylogenetic and field methods. This dissertation provides the first species-level phylogeny of Cetacea and phylogenetic tests of evolutionary hypotheses of cetacean communicative signals. Tonal sounds evolution is complex in that has likely been shaped by a combination of factors that may influence different aspects of their acoustical structure. At the inter-specific level, these results suggest that only tonal sound minimum frequency is constrained by body size. Group size also influences tonal sound minimum frequency. Species that live in large groups tend to produce higher frequency tonal sounds. The evolutionary history of tonal sounds and sociality may be intertwined, but in a complex manner rejecting simplistic views such as the hypothesis that tonal sounds evolved ‘for’ social communication in dolphins. Levels of social and tonal sound complexity nevertheless correlate indicating the importance of tonal sounds in social communication. At the intraspecific level, tonal sound variation in frequency and temporal parameters may be product of genetic isolation and local levels of underwater noise. This dissertation provides one of the first insights into the evolution of Cetacean tonal sounds in a phylogenetic context, and points out key species where future studies would be valuable to enrich our understanding of other factors also playing a role in tonal sound evolution. ^

Tocqueville in Miami: Political culture and political organizing in Miami's Cuban community

This study examines the effectiveness of civic organizations focusing on leadership and the role of culture in politics. The study is based on a quasi-experimental research design and relies primarily on qualitative data. The study focuses on Miami's Cuban community in order to examine the role of public initiative in grassroots civic and community organizations. ^ The Miami Cuban community is a large, institutionally complex and cohesive ethnic community with dense networks of community organizations. The political and economic success of the community makes it an opportune setting for a study of civic organizing. The sheer number of civic organizations to be found in Miami's Cuban community suggests that the community's civic organizations have something to do with the considerable vibrancy and civic capacity of the community. How have the organizations managed to be so successful over so many years and what can be learned about successful civic organizing from their experience?^ Civic organizations in Miami's Cuban community are overwhelmingly ethnic-based organizations. The organizations recreate collective symbols that come from community members' memories of and attachments to the place of origin they hold dear as ethnic Cubans. They recreate a collective Cuban past that community members remember and that is the very basis of the community to which they belong.^ Cuban Miami's ethnically based civic organizations have generally performed better than the literature on civic organizations says they should. They gained greater access to community ties and social capital, and they exhibited greater organizational longevity. The fit between the political culture of civic organizations and that of the broader political community helps to explain this success. Yet they do not perform in the same way or in support of the same social purposes. Some stress individual agency rather than community agency, and some pursue an externally-oriented social purpose, whereas others focus on building an internal community.^

Abstractions to support dynamic adaptation of communication frameworks for user-centric communication

The convergence of data, audio and video on IP networks is changing the way individuals, groups and organizations communicate. This diversity of communication media presents opportunities for creating synergistic collaborative communications. This form of collaborative communication is however not without its challenges. The increasing number of communication service providers coupled with a combinatorial mix of offered services, varying Quality-of-Service and oscillating pricing of services increases the complexity for the user to manage and maintain ‘always best’ priced or performance services. Consumers have to manually manage and adapt their communication in line with differences in services across devices, networks and media while ensuring that the usage remain consistent with their intended goals. This dissertation proposes a novel user-centric approach to address this problem. The proposed approach aims to reduce the aforementioned complexity to the user by (1) providing high-level abstractions and a policy based methodology for automated selection of the communication services guided by high-level user policies and (2) providing services through the seamless integration of multiple communication service providers and providing an extensible framework to support the integration of multiple communication service providers. The approach was implemented in the Communication Virtual Machine (CVM), a model-driven technology for realizing communication applications. The CVM includes the Network Communication Broker, the layer responsible for providing a network-independent API to the upper layers of CVM. The initial prototype for the NCB supported only a single communication framework which limited the number, quality and types of services available. Experimental evaluation of the approach show the additional overhead of the approach is minimal compared to the individual communication services frameworks. Additionally the automated approach proposed out performed the individual communication services frameworks for cross framework switching.

The civic achievement gap: A study on the civic knowledge, skills, and attitudes of Hispanic students in Miami-Dade County Public Schools

This study assessed the civic knowledge, skills, and attitudes of Hispanic eighth grade students in Miami-Dade County Public Schools (M-DCPS), Florida. Three hundred sixty one Hispanic students of Cuban (253), Colombian (57), and Nicaraguan (51) ancestry from 10 middle schools participated in the study. Two hundred twenty eight students were from low socio-economic status (SES) background, and 133 were of middle SES background. There were 136 boys and 225 girls. The International Association for the Evaluation of Educational Achievement Civic Education Student Questionnaire was used to collect data. The instrument assessed the students’ civic knowledge, skills, and attitudes. Multivariate analysis of variance was used to test for differences in the civic knowledge, skills, and attitudes of participants based on ancestry, SES, and gender. ^ The findings indicated that there was no significant difference in the civic knowledge, skills, and attitudes of Hispanic eighth grade students that were of Cuban, Colombian, and Nicaraguan ancestry. There was no significant difference in the civic skills and in five of the civic attitude scales for students from low SES families compared to those from middle SES families. However, there was a significant difference in the civic knowledge and in the civic attitude concerning classroom discussions and participation based on SES. The civic knowledge of middle SES students was higher than that of low SES students. Furthermore, middle SES Hispanic students displayed a higher mean score for the civic attitude of classroom discussions and participation than low SES students. There was no significant difference in the civic knowledge and in five of the civic attitude scales between boys and girls. However, there was a significant difference in the civic skills and the civic attitude of support for women’s rights between boys and girls. Hispanic girls displayed a higher mean score in civic skills than Hispanic boys. Furthermore, the mean score of civic attitude of support for women’s rights for Hispanic girls was higher than that of Hispanic boys. ^ It was concluded that Cuban, Colombian, or Nicaraguan participants did not demonstrate differences in civic attitudes and levels of civic knowledge and skills that eighth grade students possessed. In addition, when compared to boys, girls demonstrated a higher level of civic skills and a greater support for women’s rights and participation in politics and their roles in politics. Moreover, SES was demonstrated to be a key factor in the acquisition of civic knowledge, regardless of ancestry.^

Managing Quality in the Hospitality Industry:

In - Managing Quality In the Hospitality Industry – an observation by W. Gerald Glover, Associate Professor, Hospitality Management Program, Appalachian State University, initially Glover establishes: “Quality is a primary concern in the hospitality industry. The author sees problems in the nature of the way businesses are managed and discusses approaches to ensuring quality in corporate cultures.” As the title suggests, the author wants to point out certain discrepancies in hospitality quality control, as well as enlighten you as to how to address some of these concerns. “A discussion of quality presents some interesting dilemmas. Quality is something that almost everyone wants,” Assistant Professor Glover notes. “Service businesses will never admit that they don't provide it to their customers, and few people actually understand what it takes to make it happen,” he further maintains. Glover wants you to know that in a dynamic industry such as hospitality, quality is the common denominator. Whether it be hotel, restaurant, airline, et al., quality is the raison d’être of the industry. “Quality involves the consistent delivery of a product or service according to the expected standards,” Glover provides. Many, if not all quality deficiencies can be traced back to management, Glover declares. He bullet points some of the operational and guest service problems managers’ face on a daily basis. One important point of note is the measuring and managing of quality. “Standards management is another critical area in people and product management that is seldom effective in corporations,” says Glover. “Typically, this area involves performance documentation, performance evaluation and appraisal, coaching, discipline, and team-building.” “To be effective at managing standards, an organization must establish communication in realms where it is currently non-existent or ineffective,” Glover goes on to say. “Coaching, training, and performance appraisal are methods to manage individuals who are expected to do what's expected.” He alludes to the benefit quality circles supply as well. In addressing American organizational behavior, Glover postures, “…a realization must develop that people and product management are the primary influences on generating revenues and eventually influencing the bottom line in all American organizations.” Glover introduces the concept of pro-activity. “Most recently, quality assurance and quality management have become the means used to develop and maintain proactive corporate cultures. When prevention is the focus, quality is most consistent and expectations are usually met,” he offers. Much of the article is dedicated to, “Appendix A-Table 1-Characteristics of Corporate Cultures (Reactive and Proactive. In it, Glover measures the impact of proactive management as opposed to the reactive management intrinsic to many elements of corporate culture mentality.

Trajectory privacy preservation in mobile Wireless Sensor Networks

In recent years, there has been an enormous growth of location-aware devices, such as GPS embedded cell phones, mobile sensors and radio-frequency identification tags. The age of combining sensing, processing and communication in one device, gives rise to a vast number of applications leading to endless possibilities and a realization of mobile Wireless Sensor Network (mWSN) applications. As computing, sensing and communication become more ubiquitous, trajectory privacy becomes a critical piece of information and an important factor for commercial success. While on the move, sensor nodes continuously transmit data streams of sensed values and spatiotemporal information, known as ``trajectory information". If adversaries can intercept this information, they can monitor the trajectory path and capture the location of the source node. ^ This research stems from the recognition that the wide applicability of mWSNs will remain elusive unless a trajectory privacy preservation mechanism is developed. The outcome seeks to lay a firm foundation in the field of trajectory privacy preservation in mWSNs against external and internal trajectory privacy attacks. First, to prevent external attacks, we particularly investigated a context-based trajectory privacy-aware routing protocol to prevent the eavesdropping attack. Traditional shortest-path oriented routing algorithms give adversaries the possibility to locate the target node in a certain area. We designed the novel privacy-aware routing phase and utilized the trajectory dissimilarity between mobile nodes to mislead adversaries about the location where the message started its journey. Second, to detect internal attacks, we developed a software-based attestation solution to detect compromised nodes. We created the dynamic attestation node chain among neighboring nodes to examine the memory checksum of suspicious nodes. The computation time for memory traversal had been improved compared to the previous work. Finally, we revisited the trust issue in trajectory privacy preservation mechanism designs. We used Bayesian game theory to model and analyze cooperative, selfish and malicious nodes' behaviors in trajectory privacy preservation activities.^

Phylogenetic and Ecological Significance in the Evolution of Cetacean Tonal Sounds

Cetaceans are aquatic mammals that rely primarily on sound for most daily tasks. A compendium of sounds is emitted for orientation, prey detection, and predator avoidance, and to communicate. Communicative sounds are among the most studied Cetacean signals, particularly those referred to as tonal sounds. Because tonal sounds have been studied especially well in social dolphins, it has been assumed these sounds evolved as a social adaptation. However, whistles have been reported in ‘solitary’ species and have been secondarily lost three times in social lineages. Clearly, therefore, it is necessary to examine closely the association, if any, between whistles and sociality instead of merely assuming it. Several hypotheses have been proposed to explain the evolutionary history of Cetacean tonal sounds. The main goal of this dissertation is to cast light on the evolutionary history of tonal sounds by testing these hypotheses by combining comparative phylogenetic and field methods. This dissertation provides the first species-level phylogeny of Cetacea and phylogenetic tests of evolutionary hypotheses of cetacean communicative signals. Tonal sounds evolution is complex in that has likely been shaped by a combination of factors that may influence different aspects of their acoustical structure. At the inter-specific level, these results suggest that only tonal sound minimum frequency is constrained by body size. Group size also influences tonal sound minimum frequency. Species that live in large groups tend to produce higher frequency tonal sounds. The evolutionary history of tonal sounds and sociality may be intertwined, but in a complex manner rejecting simplistic views such as the hypothesis that tonal sounds evolved ‘for’ social communication in dolphins. Levels of social and tonal sound complexity nevertheless correlate indicating the importance of tonal sounds in social communication. At the intraspecific level, tonal sound variation in frequency and temporal parameters may be product of genetic isolation and local levels of underwater noise. This dissertation provides one of the first insights into the evolution of Cetacean tonal sounds in a phylogenetic context, and points out key species where future studies would be valuable to enrich our understanding of other factors also playing a role in tonal sound evolution.

Logical simulation of communication subsystem for Universal Serial Bus (USB)

The primary purpose of this thesis was to design a logical simulation of a communication sub block to be used in the effective communication of digital data between the host and the peripheral devices. The module designed is a Serial interface engine in the Universal Serial Bus that effectively controls the flow of data for communication between the host and the peripheral devices with the emphasis on the study of timing and control signals, considering the practical aspects of them. In this study an attempt was made to realize data communication in the hardware using the Verilog Hardware Description language, which is supported by most popular logic synthesis tools. Various techniques like Cyclic Redundancy Checks, bit-stuffing and Non Return to Zero are implemented in the design to provide enhanced performance of the module.

Tocqueville in Miami : political culture and political organizing in Miami's Cuban community

This study examines the effectiveness of civic organizations focusing on leadership and the role of culture in politics. The study is based on a quasi-experimental research design and relies primarily on qualitative data. The study focuses on Miami's Cuban community in order to examine the role of public initiative in grassroots civic and community organizations. The Miami Cuban community is a large, institutionally complex and cohesive ethnic community with dense networks of community organizations. The political and economic success of the community makes it an opportune setting for a study of civic organizing. The sheer number of civic organizations to be found in Miami's Cuban community suggests that the community's civic organizations have something to do with the considerable vibrancy and civic capacity of the community. How have the organizations managed to be so successful over so many years and what can be learned about successful civic organizing from their experience? Civic organizations in Miami's Cuban community are overwhelmingly ethnic-based organizations. The organizations recreate collective symbols that come from community members' memories of and attachments to the place of origin they hold dear as ethnic Cubans. They recreate a collective Cuban past that community members remember and that is the very basis of the community to which they belong. Cuban Miami's ethnically based civic organizations have generally performed better than the literature on civic organizations says they should. They gained greater access to community ties and social capital, and they exhibited greater organizational longevity. The fit between the political culture of civic organizations and that of the broader political community helps to explain this success. Yet they do not perform in the same way or in support of the same social purposes. Some stress individual agency rather than community agency, and some pursue an externally-oriented social purpose, whereas others focus on building an internal community.

Trajectory Privacy Preservation in Mobile Wireless Sensor Networks

In recent years, there has been an enormous growth of location-aware devices, such as GPS embedded cell phones, mobile sensors and radio-frequency identification tags. The age of combining sensing, processing and communication in one device, gives rise to a vast number of applications leading to endless possibilities and a realization of mobile Wireless Sensor Network (mWSN) applications. As computing, sensing and communication become more ubiquitous, trajectory privacy becomes a critical piece of information and an important factor for commercial success. While on the move, sensor nodes continuously transmit data streams of sensed values and spatiotemporal information, known as ``trajectory information". If adversaries can intercept this information, they can monitor the trajectory path and capture the location of the source node. This research stems from the recognition that the wide applicability of mWSNs will remain elusive unless a trajectory privacy preservation mechanism is developed. The outcome seeks to lay a firm foundation in the field of trajectory privacy preservation in mWSNs against external and internal trajectory privacy attacks. First, to prevent external attacks, we particularly investigated a context-based trajectory privacy-aware routing protocol to prevent the eavesdropping attack. Traditional shortest-path oriented routing algorithms give adversaries the possibility to locate the target node in a certain area. We designed the novel privacy-aware routing phase and utilized the trajectory dissimilarity between mobile nodes to mislead adversaries about the location where the message started its journey. Second, to detect internal attacks, we developed a software-based attestation solution to detect compromised nodes. We created the dynamic attestation node chain among neighboring nodes to examine the memory checksum of suspicious nodes. The computation time for memory traversal had been improved compared to the previous work. Finally, we revisited the trust issue in trajectory privacy preservation mechanism designs. We used Bayesian game theory to model and analyze cooperative, selfish and malicious nodes' behaviors in trajectory privacy preservation activities.