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The healthcare workforce potentially faces substantial challenges if fewer women pursue surgery. It is evident that there are many women in the graduating classes from medicine, yet this is not represented at the higher levels in surgery. While some countries (e.g., UK) have seen an increase in female surgeons and consultant surgeons over the last decade, others (e.g., Ireland) have seen figures remain static. Worldwide, the number of women in surgery at the consultant level remains low compared to other specialities. While research has shown challenges and barriers for women in surgery, this study explores the perceptions of female surgeons and the colleagues and patients of female surgeons on the topic of women in surgery. This research study is epistemologically grounded in social constructionism and focuses on how knowledge is constructed through social interactions. My research study involved a narrative inquiry from a methodological perspective adopting a storytelling approach to capture female surgeons', colleagues', and patients of female surgeons' perceptions of gender in surgery; exploring how they make sense of their experiences and others and their conceptualisations of working in the NHS in Scotland or the HSE in Ireland. A qualitative research approach drawing on biographical narrative interpretive interviewing provides a comprehensive picture of the multiplicity of issues existing for female surgeons in the two countries. This approach was employed as it emphasises the socially constructed nature of reality and helps provide a rich and complex understanding of female surgeons' issues. My sample included 29 female surgeons, 10 male and eight female colleagues (e.g., surgeons, nurses, physician associates, anaesthetists), and 6 male and 7 female patients. Framework analysis was used to identify initial key themes for coding the data. Narrative analysis was used to explore what and how participants narrated their stories. The overarching themes derived from the data across all stakeholder groups indicated gendered surgical cultures, gendered surgical career transitions, and intersecting identities of surgeons. My findings showed that gendered surgical cultures played an essential role in shaping surgical careers and, in many cases, acted as a barrier to career progression, particularly for female surgeons. In addition, the data indicated that surgical cultures transcend country cultures outlined in Hofstede's cultural dimensions. I identified the multiplicity of time-related and spatial transitions of doctors from medical school to surgical training and consultant positions and the influences of these transitions on work (e.g., careers) and home life (e.g., families). Finally, I uncovered how female (and male) surgeons' gender, age, ethnicity, and professional identities intersect to influence interactions in the surgical environment, especially for female surgeons. Novel findings identified that gendered surgical cultures transcend country cultures and female surgeons are keen to overcome these surgical cultures to progress in surgery. Findings also identified multiple transitions at different stages of training impacting several domains. Finally, findings identified intersecting identities of surgeons, including male surgeons and the influence of these intersections. In conclusion, this study identified issues that could be addressed through enhancing educational policies and practice within surgical training on gendered challenges for women in surgery and to improve surgical cultures and transitions. It is hoped that the recommendations from this thesis will contribute to diversifying the healthcare workforce and addressing issues on gendered surgical cultures.

There have been two key difficulties concerning the study of indigenous rituals, religious conversion and change among the Igbo of South-eastern Nigeria, both before and after the missionary upsurge of the mid-nineteenth Century. First is the inadequate awareness or lack of reflexivity by some scholars regarding the resilience of the Igbo indigenous religions. Second is the neglect of oral sources and the overdependence on missionary archives. This thesis draws on field research on the Presbyterian Church of Nigeria (PCN) and the Ogo society in Amasiri. The research method follows a triangulation research design which incorporates an ethnographic methodology. This involves participant observation and interviews, thus allowing for a set of guidelines that connect theoretical paradigms to strategies of inquiry and methods for collecting empirical data. Within the Amasiri clan it is expected that every male will be initiated into the Ogo society as a means of attaining manhood as well as incorporation into the adult group. Refusal to be initiated into the society amounts to ostracisation and a loss of social relevance. The thesis examines the establishment, growth and impact of Christianity among the Amasiri clan in its different phases (colonial and post-colonial eras) - 1927-2008. It demonstrates the interaction between Amasiri indigenous religions and Christianity, in order to show how and to what extent the Ogo society has endured over time. The thesis analyses specific beliefs and ritual practices of the Ogo society and Christianity, paying close attention to the resultant tensions as well as the dynamic of acquired and lived religious identities. In view of the complex patterns of interaction between Christianity and the Ogo society, the thesis explores the following questions: What makes the Ogo society an integral part of the socio-religious life of Amasiri and what powers and identity does it confer on initiates? How are these predominantly indigenous cultural features, expressed within Christian spirituality? What effect does the construction and negotiation of religious identities have on the interaction and co-existence of Christians and members of the Ogo society? Furthermore, three themes were central to this research: the first is the gender dynamic of initiation processes into the Ogo society. The second is the pattern of religious change, identity and politics of Christianity and indigenous cultures. The third is analysing the need for and limits on effective dialogue between Christians and members of the Ogo society. The thesis raises a crucial question, whether religious conversion is partial or total repudiation of indigenous cultures. These analyses propose a viable means of negotiation between Christianity and the Ogo society in Amasiri. It sets the stage for a dialogue between Christianity and the Ogo society, a dialogue that takes the indigenous context seriously.

'A treatise of algebra historical and practical' (London 1685) by John Wallis (1616-1703) was the first full length history of algebra. In four hundred pages Wallis explored the development of algebra from its appearances in Classical, Islamic and medieval cultures to the modern forms that had evolved by the end of the seventeenth century. Wallis dwelt especially on the work of his countrymen and contemporaries, Oughtred, Harriot, Pell, Brouncker and Newton, and on his own contribution to the emergence of algebra as the common language of mathematics. This thesis explores why and how A treatise of algebra was written, and the sources Wallis used. It begins by analysing Wallis's account of mathematical learning in medieval England, never previously investigated. In his researches on the origins and spread of the numeral system Wallis was at his best as a historian, and initiated many modern historiographical techniques. His summary of algebra in Renaissance Europe was less detailed, but for Wallis this part of the story set the scene for the English flowering that was to be his main theme. The influence of Oughtred's Clavis on Wallis and his contemporaries, and Wallis's efforts to promote the book, are explored in detail. Wallis's controversial account of Harriot's algebra is also examined and it is argued that it was better founded than has sometimes been supposed and that Wallis had direct access to Harriot's algebra through Pell. Many other chapters of A treatise of algebra contain mathematics that can be linked or traced to Pell, a hitherto unsuspected secret of the book. The later chapters of the thesis, like the final part of A treatise of algebra, explore Wallis's Arithmetica infinitorum and the work which arose from it up to Newton's foundation of modern analysis, and include a discussion of Brouncker's treatment of the number challenges set by Fermat. The thesis ends with a summary of contemporary and later reactions to A treatise of algebra and an assessment of Wallis's view of algebra and its history.

This Article analyzes how to challenge AAPI (Asian American Pacific Islander) hate—defined as explicit negative bias in racial beliefs towards AAPIs. In economics, beliefs are subjective probabilities over possible outcomes. Traditional neoclassical economics view beliefs as inputs to making decisions with more accurate beliefs having indirect, instrumental value by improving decision-making. This Article utilizes novel economic theories about belief-based utility, which economically captures the intuitive notion that people can derive pleasure and pain directly from their and other people's beliefs. Even false beliefs can offer comfort and reassurance to people. This Article also draws on interdisciplinary and multidisciplinary theories about deliberate ignorance—defined as the conscious choice by individuals to ignore certain knowledge or particular information. This Article studies how to change people's beliefs about what a person of a certain race is likely to do, will do, or has done. This Article defines explicit racism to entail hateful racial beliefs, which can be due to disinformation or misinformation. Hateful beliefs can fuel misunderstanding and violence. This Article focuses on challenging AAPI hate due to the author's experiences with AAPI hate. This Article examines how and why explicit racism is wrong. This Article analyzes subjective beliefs, hate crime laws, and explicit racism. This Article advocates three ways to challenge AAPI hate: positive racial education and mindfulness, positive racial conversations and communications, and positive racial associations, cultures, and norms.

The goal of this dissertation was to illuminate how an immersive study abroad program enabled my Black and African American Historically Black Colleges and Universities (HBCU) students to have meaningful language acquisition, cultural exploration, and identity expansion experiences. The methods used in this research reflect the qualitative narrative nature of the cross-cultural narrative inquiry (He, 2003, 2006, 2010; Phillion & He, 2008; Phillion et al., 2009; Sharma & Phillion, 2021). Thus, to accurately capture the participants’ stories, I employed a variety of methods, gathering data through semi-structured interviews and the collection of personal artifacts, such as journal writings, pictures, and mementos. The immersive program is a collaboration with a school in Costa Rica, which provides language acquisition, cultural exploration, and identity expansion experiences within the context of a new culture (Bakhtin, 1981; Chomsky, 1957; Krashen, 1981). The study focused on three former HBCU students: Flaco, Brianna, and Ten (pseudonyms). The study demonstrated how the three former HBCU student transformed through the spaces they encountered. The stories of the three participants are captured within the context of the chronotopic (Bakhtin, 1981) encounter and New Dimension search in Costa Rica. The following emerging themes and findings were identified: (1) HBCUs as a Special Place for Solidifying Black Identity; (2) “My Mom Had Baked My Financial Advisor Cookies”: Barriers to Study Abroad; (3) Languages: Encounter of African American Vernacular English (AAVE), Standard English, and Spanish; (4) Cultures: Encounter of Black, African American, and Costa Rican Cultures; (5) Identities: “A Rose That Grew from a Crack in the Concrete”; and (6) Pura Vida as New Dimension. These findings illustrate the ever-intertwined nature of languages, cultures, and identities enhanced by immersion experiences abroad. Implications for me as a study abroad program leader and instructor are shared as well as those for other program leaders and the field of Curriculum Studies.

Human beings routinely engage in purchasing and making payments for goods and services. Payment method evolves as technology advances. According to statistical reports and observations, mobile payment has become a dominant method for people in China to pay for their purchases. In contrast, this payment method is not widely adopted by those in the U.S., where the infrastructure for it has already been established. We assumed the difference in the evaluation for mobile payment by people from two countries might lead to the gap in its adoption.Suggested by the rational choice theory, people could weigh the potential benefits and costs of mobile payment usage before they make a decision on whether to use it over traditional methods, such as cash and credit cards. To identify and specify these benefits and costs, we reviewed pre-existing studies on technology adoption. We realized many of these studies focused a great deal on the impact of the benefits and neglected that of the costs of a particular technology or digital service on people’s intention to use it. To bridge the gap, we gave an equal amount of attention to and extracted an equal number of benefits and costs for mobile payment adoption from widely used theories and models, such as uses and gratifications, technology acceptance model, and privacy calculus theory. We then built a research model and hypothesized the impacts of these factors on their usage intention for mobile payment.To test our research model and hypotheses, we conducted an online survey and received 1,065 valid responses from the U.S. and 473 from China. Through our statistical analyses, we noticed that both U.S. and Chinese respondents’ perceived usefulness and convenience of mobile payment, and their trust in its security significantly impacted their usage intention. The perceived enjoyment of mobile payment predicted only U.S. respondents’ usage intention, while privacy concerns predicted only Chinese respondents’. The age difference of respondents played an effective role in this study, but their differences in gender, educational background, and level of income did not. In addition, U.S. respondents projected a more collectivistic culture and Chinese respondents projected a more individualistic one.These results imply that when choosing between mobile payment and a traditional method, the method that costs consumers less time and effort to complete a transaction is preferred. Many people may not be fully aware of the potential privacy risks of fast evolving technologies. Those who are aware of the risks may choose to ignore them as long as these technologies are rewarding. Our respondents were mainly from younger generations, who showed distinguished ideologies and cultural values. This study faces some limitations, such as the unfiltered noise in data; the lack of knowledge of some respondents for mobile payment; and possibly outdated measures for modern cultures. Future research to break these limitations is encouraged.

This phenomenological study was an investigation of four U.S. international music teachers’ experiences in music teaching, performing, creating, as well as their conceptions of musical creativity. A music educational conceptual model, Twelve Continuum Transmission Framework (TCTF), provided the theoretical framework for identifying culturally diverse aspects of participants’ music teaching and cultural features in their perspectives on creativity. Research questions included: What does the participants’ music teaching consist of in terms of cultural aspects, How do the participants conceive of creativity in regards to cultural aspects, and What are the implications of these participants’ conception of creativity, within their culturally diverse musical realities, on the music education profession? Four international music teachers who participated in this study experienced in teaching their ethnic music, responded to changes in cultural context, and music teaching adaptation. They represented different musical practices and cultural backgrounds. Data were collected from in-depth individual interviews, observations, artifacts, and researcher memos relating to their music teaching, performing, and creating practices. The analysis included thick descriptions of the international music teachers’ cultural realities and essays on their common conceptions of creativity that emerged from the variation of music tradition and teaching practices. Findings suggest that the international music teachers’ encounter with another cultural context, the U.S., recontextualized their teaching methods and expanded their conception of creativity. In this study, shifting ownership was considered an overall disposition in which various aspects can play key roles. A disposition or attitude of shifting musical ownership was evident in the international music teachers’ conception of creativity. This shift in musical ownership seemed to be related to their personalization of music through performing and creating, flexible approach to authenticity, freedom of students’ musical expression, and approach to other cultures’ music.

Three-dimensional (3D) cell culture and tissue engineering offer a unique avenue for therapeutic interventions. A 3D tissue model potentially revolutionizes the challenges to mimic the in vivo physiological conditions. Recent advances in microfluidic technology have accelerated the development of 3D tissue models. For instance, droplet-based microfluidics allows tiny droplets to serve as bioreactors. This thesis introduces for the first time a new approach using liquid marble, which is generated by encapsulating an aqueous liquid droplet with a hydrophobic powder. This platform is reliable for 3D scaffold-free tissue engineering. This technology is more versatile and more adaptable than existing hanging-drop systems and other scaffold-based microfluidic systems. The use of liquid marble as a bioreactor has led to a number of interesting applications. The first application is culturing multiple cell spheroids. For this purpose, a novel cell culture protocol with floating the liquid marble was developed. As a proof of concept, spheroids of olfactory ensheathing cells (OECs) were grown in a liquid marble. The liquid marble was generated simply by encapsulating a droplet of medium containing cells with hydrophobic powder. The powder coating creates a robust, porous and apparently elastic shell, which allows gas exchange. The liquid marble was then floated by placing it on a liquid bath. The interfaces between the hydrophobic coating and the supporting liquid bath are separated by an air layer. This air layer contributes to the low friction and facilitates liquid marble to move. The mobility enhances internal flow and allows cell-cell interaction. Further, the liquid bath also helps to increase relative humidity and minimize evaporation. This protocol provides an opportunity to explore the interaction of different cell types to form co-culture spheroids. The second application is the use of liquid marble as a 3D in-vitro model for cell-cell interactions. Liquid marbles create a distinct microenvironment for cell growth and interaction. The insertion of a second cell type was modeled by coalescence of the two liquid marbles. The merged liquid marble serves as an environment for the interaction between two distinct cell types. As a model of the hostile environment, nerve debris and meningeal fibroblast were grown to generate co-cultured spheroid that mimics the features of spinal cord injury (SCI). We then assessed the potential of Olfactory Ensheathing Cells (OECs) to interact with the nerve debris within an fibroblastic tissue. Altogether, the results indicate the feasibility of a liquid marble for studying the survival and adherence of transplanted cells. This liquid marble is achievable for developing the test model for cell-based therapy. The third application is the use a liquid marble as the bioreactor for slow-release of drugs and factors as well as minimizing evaporation. A spherical agarose gel was loaded with growth factor and embedded within a liquid marble. The release of growth factor showed a significant increase in cell aggregation and subsequent production of larger spheroids. This model promises a wide range of studies that requires sustained release. Generally, liquid marbles are subjected to evaporation. Thus, the evaporation rate in the presence of the agarose gel was evaluated. The experiments showed that there was no obvious trend in the volumetric changes due to both water absorption and water loss due to evaporation. The results indicate that liquid marbles can be used to study the efficacy of drug delivery. The final application is the use of slow release growth factor to form a toroid tissue. The embedded agarose gel inside a liquid marble releases a growth factor to attract and assemble cells into a tissue with the shape of a toroid. The harvested toroid tissue was placed on non-adherence well plate and treated with the growth factor to investigate its closure. The geometric growth during the closure process was then measured and modelled. The application is promising for high-throughput screening of drugs on 3D wound healing. All four applications provides a proof of concept for the use of liquid marbles as bioreactors and further expansion towards 3D tissue models for drug discovery.

On January 25, 2017, during his first week in office, President Donald Trump signed an Executive Order calling for the “immediate construction of a physical wall on the southern border” of the United States . Such a wall would span more than one thousand miles, across many different habitats and many different communities . Before a wall will be built, numerous questions must be answered: Which environmental laws apply? How might all this work? On February 16, ELI convened experts to discuss how environmental law and policy may interact with the Executive Order, and to spark discussion about important environmental resources and communities along the border . Below, we present a transcript of the event, which has been edited for style, clarity, and space considerations .

This thesis reports the results of a two-part study investigating preferred leadership communication styles across multiple cultural clusters. Utilizing a survey, part one identified the three most preferred leader communication styles (i.e., dominant, dramatic, contentious, attentive, animated, open, friendly, relaxed, impression leaving) in six cultural clusters. Using focus group data, the second part provides insight into subordinates’ perceptions of how these communication styles are enacted by leaders in each cluster. Guidelines on how to better communicate are offered to expatriates in hopes of helping them more successfully complete overseas tasks. Such guidelines are needed due to the high percentage of failed overseas missions which cost corporations millions of dollars each year.

With growing popularity of the use of social network sites/services (SNSs) throughout the world, the global dominance of SNSs designed in the western industrialized countries, especially in the United Sates, seems to have become an inevitable trend. As internationalization has become a common practice in designing SNSs in the United States, is localization still a viable practice? Does culture still matter in designing SNSs? This dissertation aims to answer these questions by comparing the user interface (UI) designs of a U.S.-based SNS, Twitter, and a China-based SNS, Sina Weibo, both of which have assumed an identity of a “microblogging” service, a sub category of SNSs. This study employs the theoretical lens of the theory of technical identity, user-centered website cultural usability studies, and communication and media studies. By comparing the UI designs, or the “form,” of the two microblogging sites/services, I illustrate how the social functions of a technological object as embedded and expressed in the interface designs are preserved or changed as the technological object that has developed a relatively stable identity (as a microblogging site/service) in one culture is transferred between the “home” culture and another. The analysis in this study focuses on design elements relevant to users as members of networks, members of audience, and publishers/broadcasters. The results suggest that the designs carry disparate biases towards modes of communication and social affordances, which indicate a shift of the identity of microblogging service/site across cultures.

This study investigates whether four Indigenous State primary principals rely on spiritual leadership to inform their leadership role in schools. I investigate the four principals‟ leadership through an analysis of a series of interviews, documents and observations conducted at the four case-study sites. I was particularly interested in the under representation of Indigenous peoples in leadership and their voices being marginalised or misrepresented on a number of important debates due to Australia‟s colonial history and the potency of postcolonialism. There were two political debates prominent during this period. These were the Liberal government‟s intervention in the Northern Territory in response to the “National Emergency” of the abuse of Indigenous children in 2007 and the Prime Minister, Mr. Kevin Rudd‟s apology in February 2008 to the stolen generations on behalf of the Australian government. I engage Foucault‟s notions of discourse and truth (1971) and analytic of power/knowledge (1980), biopower (1984) and postcolonial theories (Ashcroft, Griffiths, & Tiffin, 2000) to provide the theoretical frame for conceptualising this study into spiritual leadership. I take a critical discourse approach (Fairclough, 2001) to the analysis of the principals‟ interview talk in order to ascertain whether the principals are operating at the deeper levels of society where representations and positions are formed and reformed often engaging symbol, metaphor and at times, myth. I was interested to explore the principals‟ perceptions of their leadership through a deconstruction of their use of symbol and metaphor. The research project questions whether spiritual leadership is enacted by the principals. The thesis acknowledges that, due to the underrepresentation of Indigenous principals, even emancipatory, visionary and spiritual leadership may not be sufficient to transform postcolonial power differentials in Australia which represent Indigenous peoples and cultures as inferior to white people and cultures. The analysis firstly investigates whether the leaders resist these negative representations of Indigenous peoples and their cultures then moves to the inner world of the leaders whereat more complex notions of the leaders‟ vision, purpose and leadership enactment are explored. The thesis acknowledges that it is at these levels where the presence of Spirit or a sense of spirituality may inform the principal‟s leadership role.

Immigration and international “floating populations” have increased in the past decade, arousing marketers’ interest in culture. In particular, culture has been used for analysing the direction of market trends, as well as providing a better understanding of consumers’ needs, expectations and preferences within and across countries. However, cross-cultural research has been hampered by the common use of nationality as a surrogate for cultural affiliation, even though a variety of ethnic, social class, lifestyle, and subcultures exist, particularly in countries that have been built from large immigrant populations such as the United States, Canada, Australia and New Zealand (Tan, McCullough, and Teoh, 1987). Furthermore, within the tourism discipline, the study of ethnic minorities has not received as much attention as specific populations of ethnic groups such as black American, Hispanic, and Chinese in the United States. This study investigated the influences of culture on travel lifestyle and behaviour, through the comparison of Korean Australians and Koreans in Korea. Korean residents who live in Korea (N = 325) and Koreans who live in Australia (N = 306) completed a self-administered questionnaire. The questionnaire sought information in regard to travel lifestyle and behaviour as well as personal values, sensation-seeking behaviour and travel experiences, in order to investigate factors associated with the differences between the two groups in travel lifestyle and behaviour. Socio-demographic characteristics of the sample were also measured. Furthermore, a measure of acculturation was taken for the Korean Australians. Data were analysed using factor analysis, t-test, one-way ANOVA, multiple regression analysis, chi-square and cluster analysis to test the proposed hypotheses. The results of this study showed differences between the two groups of Koreans in respect of travel lifestyle and behaviour, personal values, sensationseeking behaviour and travel experiences. Cluster analysis identified five distinct groups: “affluent group travellers”, “low resource group travellers”, “active independent travellers”, “non- active independent travellers”, and “low-interest travellers”. Korean Australians were more likely than Koreans to be represented in the clusters of “active independent travellers”, “non-active independent travellers”, and “low-interest travellers”. Koreans were more likely to want to travel as part of a group than Korean Australians. Relationships between personal values, sensation-seeking behaviour and travel experiences, as well as travel lifestyle and behaviour were also found. The “low resource group traveller” within Korean Australians was likely to report having low “community values” and “life values”, while the same cluster within Koreans was likely to report having low “social values” and “life values” as opposed to the “active independent traveller” for both samples of Koreans. The “active independent traveller” in both Korean groups was more likely to report holding a strong preference for “novelty” seeking than the other cluster travellers. Korean Australians who undertake frequent international travel were more likely to be in the “active independent travellers” cluster, whereas Koreans who are frequent international travellers were more likely to be in the “affluent group travellers” cluster. Acculturation also predicted, to some extent, the travel lifestyle and behaviour of Korean Australians. Demographic variables were mostly irrelevant to travel lifestyle and behaviour in each group. This study confirmed that personal values and sensation-seeking behaviour seemed to be associated with the different travel lifestyles and behaviour of Korean Australians compared to Koreans. The differences of travel lifestyle and behaviour may be caused by different cultures. Findings of the current study reinforce the importance of culture in the tourism market. The results revealed that overall predictability of travel lifestyle and behaviour by sensation-seeking behaviour was stronger than the predictability of travel lifestyle and behaviour by personal values. However, variables such as personal values, sensation-seeking behaviour, travel experiences and demographic characteristics, which were expected to predict travel lifestyle and behaviour, did not appear to explain much variance. Future research is recommended to investigate other factors that may predict travel lifestyle and behaviour among other ethnic groups. This study suggests that marketers should acknowledge that consumers in countries with diverse cultural backgrounds also need differentiated services and products. Crosscultural insights provide opportunities for marketers to develop and extend markets in multicultural countries.

Francesco Berlinghieri's Geographia, an Italian verse paraphrase of Ptolemy's Geography accompanied by thirty-one engraved maps, was printed in Florence in 1482. Through the donation of hand-illuminated copies of the book to the sons of Ottoman Sultan Mehmed II, Bayezid and Cem, it served as an object of cross-cultural interchange between Florence and the Ottoman imperial court in Istanbul. My dissertation provides the first comprehensive treatment of the Geographia and argues that the work's function as an object of international exchange cannot be separated from consideration of concerns often dismissed as parochial by previous scholarship. Print-shop practices, vernacular literary conventions, and Florence's rich tradition of cartographic manuscript production all have broad implications for our understanding of the work's cross-cultural function. Its selection as diplomatic gift is best understood in the context of its utility and meanings for those who routinely produced, read, commissioned and conceived such works. Further, in considering this important printed cartographic work within the larger context of early modern Italian visual culture this project evaluates and problematizes commonplace notions of early printing's claims to accuracy, authority, and standardization. Printed copies of the Geographia exhibit hand-colored maps, illuminated frontispieces, family coats of arms, and other unique modifications. The analysis of such objects is crucial to our understanding of the still contested relationship between manuscript and print cultures in the history of the early modern book. Ultimately, this project contends that technologically and artistically experimental books like the Geographia served, through their modification for eminent buyers and dedicatees, to construct networks of learned, powerful, and wealthy individuals that spanned the early modern Mediterranean.

Spontaneous activity in neuronal networks in vitro is common and has been well documented. However, alteration of spontaneous activity in such networks via conditioning electrical stimulation has received much less experimental attention. Two different patterns of electrical stimulation were used to enhance or depress the level of spontaneous activity in spinal cord cultures. High-frequency stimulation (HFS), a method routinely shown to increase the efficacy of synaptic transmission, was employed to augment spontaneous activity. Low-frequency stimulation (LFS), the technique often applied to depress synaptic efficacy, was employed to decrease spontaneous activity. In addition, LFS was used to reverse the effect of HFS on spontaneous activity. Likewise, HFS was applied to counter the effect of LFS. Because these networks were grown on multi-microelectrode plates (MMEPs), this allowed the simultaneous stimulation of any combination of the 64 electrodes in the array. Thus, the possible differences in response to single versus multi-electrode stimulation were also addressed. Finally, test-pulses were delivered before and after the conditioning stimulation on the same stimulation electrode(s) in order to assess the change in mean evoked action potentials (MEAPs). Dissociated spinal tissue from embryonic mice was allowed to mature into self-organized networks that exhibited spontaneous bursting activity after two weeks of incubation. Spontaneous activity was monitored from up to 14 recording channels simultaneously. Although uniform responses to stimulation across all recording electrodes were rarely observed, a large majority of the recording channels had similar responses. Spontaneous activity was increased in 52% of 89 HFS trials, whereas activity was decreased in 35% of 75 LFS trials. The duration of most of these increases was less than 5 minutes. When there were substantial and long-term (> 15 min) changes in spontaneous activity, the opposing stimulation pattern successfully reversed the effect of the previous stimulation. The percent change in MEAPs following conditioning stimulation suggested that synaptic modification had taken place in 75% of all test-pulse stimulation trials.

In Zimbabwe cervical cancer now accounts for about 25% of women's cancer mortality. Even women aged as young as fifteen years are dying from this disease. The purpose of this study was to examine critically the factors that might contribute towards Zimbabwean women's Pap smear seeking behavior. The Fishbein, Bandura, Triandis, Kanfer, Becker and Middlesstadt's (1991) behavior and behavior change model provided the framework for identification of relevant study concepts. The study sample consisted of randomly selected sexually active rural women aged between 12 years and 84 years who live in Shamva district and have not had a hysterectomy. Five hundred and fourteen women responded to the questionnaires. Ninety percent of the women had never had a Pap smear and 84% had no knowledge of a Pap smear. Despite never having a Pap smear and lacking prior knowledge of the purpose of Pap smear eighty percent of the women expressed positive beliefs about Pap smear after they had been taught. There was a marginal difference in the responses to the beliefs, occupation, age and type of village between women who had prior knowledge of Pap smear (Plan A) and those who lacked prior knowledge (Plan B) but significant predictors emerged only when the total sample was analyzed. The major constraints for obtaining a Pap smear were that it was not offered routinely at the health institutions and was expensive. Moreover, women had no money or health insurance. Further, health care providers often did not advise women to have a Pap smear. While seventy seven percent of women had skills to access health care services, more than half of the women in the overall sample felt that health providers did not care about their feelings and neither offered explanations nor respected their right to make decisions about their health. Education level, financial situation, occupation, respondent's village, positive beliefs and age were predicting factors that influenced the likelihood of having a Pap smear. Women who perceived fewer barriers were more likely to utilize the Pap smear in future. Based on these findings health care providers need to offer information about Pap smear and respect clients' rights to make decisions regarding their health. It is recommended that the government of Zimbabwe institute a cervical cancer screening policy that minimizes barriers to women's access to Pap smear, targets the risk age groups and allocates resources for the treatment of cervical cancer.

Contested Bodies and Cultures examines the institution of public health and the broader medical culture to understand the ways in which public health discourse was utilized by a broad array of people in Los Angeles to advance their agendas in the rapidly developing city. These agendas often shaped immigrants' places within the Los Angeles social order. Like immigration laws, public health ordinances had the power to expand and restrict people's access to citizenship and relationship to the nation-state. Public health officials viewed Mexicans and their culture, often considered a backward culture, as antithetical to their efforts at progress. Health officials launched Americanization programs in hopes that assimilation would eliminate Mexicans as an obstacle to progress. Health officials were very concerned that Mexicans caused high disease rates and epidemics that would be costly to the county. In contrast to the programs developed for Mexicans, health officials did not develop any significant health care programs for the Japanese and Chinese communities. While health officials characterized health and cleanliness as tropes for healthy citizens and a strong nation, spurring the development of health programs for Mexicans, for the most part, they did not extend similar programs to Asian communities. In fact, Chinese and Japanese communities often supplemented city and county health department budgets so that they could hire public health nurses to work with their communities. To analyze health and city officials attitudes towards Chinese and Japanese communities, I turn from a discussion of public health programs to an examination of public health as discourse that became reified into city ordinances which circumscribed these communities. These ordinances reveal how health officials racialized the Chinese and Japanese in opposition to the body politic and by extension, citizenship.

Cultural dissonance refers to individuals' negative reactions to a discrepancy in beliefs, values, and behavioral expectations across the various contexts in which they reside. This dissertation includes two studies examining the antecedents of students' experiences of dissonance and features within the school environment that help ameliorate dissonance between home and school. The first, a quantitative study, included survey data collected from an ethnically and economically diverse sample of students (N = 599) in the fifth grade of elementary school and the following two years of middle school. Growth curve analysis indicated that on average there was little change in cultural dissonance for these students. However, there was significant variation among students in change in cultural dissonance across the three years. Ethnicity and socioeconomic status were not significant predictors of students' initial level of dissonance, nor did these variables explain the change in dissonance across the transition from elementary to middle school. Students' perception of the degree to which their classrooms emphasized relative ability and competition (ability goal structure) and students' sense of school belonging were significant predictors of dissonance in the fifth grade. If students perceived their middle school classrooms as more ability-focused than their elementary school classrooms and felt a lower sense of belonging to their middle school than to their elementary school, they experienced an increase in dissonance. This increase was attenuated if students attended a middle school in which teachers reported that there was an emphasis on understanding, effort, and improvement (task goal structure). The second, a qualitative study, included interview data from 49 students who were identified as high in dissonance on the survey. Using an interview protocol, students were asked a series of questions about their experiences at home and school and why they felt different from others at school. Analysis of data using both inductive and deductive methods revealed reasons for dissonance that transcended ethnic group membership. These included religious beliefs, socioeconomic status, the relevancy of curriculum to students' lives, and the motivational culture and interpersonal relationships in the classroom and school. Both studies point to the importance of teacher and peer support within a learning environment in which understanding and mastery are encouraged and competition is minimized.

This dissertation explores how migration to Germany and the experience of cultural, linguistic, and social displacement are conveyed in the prose texts of three women writers of Turkish origin, Emine S. Ozdamar, Aysel Ozakin, and Renan Demirkan. Focusing on issues of cultural identity, the dissertation analyzes the ways in which the displaced protagonists negotiate their subject positions, and the ways in which these subject positions express concerns of cultural hybridity. The thesis relies on Salman Rushdie's theories on migrant literature and on Homi Bhabha's concept of an international culture that is based on a 'third space,' the inscription and articulation of culture's hybridity. This dissertation examines postcolonial theory in the German-Turkish context. It explores the specificity of this hybridity in Ozdamar's, Ozakin's and Demirkan's texts and in the reception of these texts. My thesis investigates how Ozdamar's, Ozakin's, and Demirkan's protagonists construct the 'third space,' how they articulate their hybrid identities, and most importantly how they deal with this experience of a space between cultures and its hybrid identities. The introductory chapter outlines the critical reception of migrants' literature in pre- and post-1989 Germany as well as the different ways in which the authors have situated themselves in the 1980s and 1990s. In the following chapters, I focus on the negotiations of hybridity and the 'third space' in the aesthetic medium, i.e. the prose texts. I explore the construction of hybridity along the lines of deterritorialization and reterritorialization (chapter 2), of the headscarf as a signifier that negotiates tradition and 'modern' influences (chapter 3), and of the tension between language and the body (chapter 4). Inhabiting a third space, I argue, proves to be not only enriching but also conflicting and delimiting. This dissertation shows the diversity of Turkish-German texts often subsumed under the lable Migrantenliteratur. It problematizes the authority and authenticity to which the term 'cultural identity' lays claim. The study demonstrates that cultural production is a dynamic, politicized process. Challenging the parameters of the meaning of a 'German' or 'Turkish' culture, it contributes to the study of migrants' literature as a growing realm of theoretical and literary inquiry.

Over the course of seven years, professional learning communities were formed in Southfield and Waterford, two Oakland County, MI school districts. These communities, which included teachers from all grade levels, attempted to change local school and district cultures. Members of the Waterford and Southfield learning communities constructed literacy-based learning opportunities for their district colleagues, drawing on their experiences in the Oakland Writing Project, a National Writing Project-affiliated site, and as demonstration site team members with the Michigan English Language Arts Framework (MELAF) Project, a federally-funded state standards effort. This study focuses on five exemplary teacher-leaders who helped articulate the vision and orchestrate the concrete steps these learning communities took. By reflecting on written and oral narratives and artifacts provided by the informants for this study---one elementary teacher, one middle school teacher, one high school teacher, and two professional development consultants---I attempt to understand what permitted them to act with agency in both classroom and collegial contexts. Speaking as their collaborator and as a practicing teacher-researcher, I argue that these teacher-leaders drew upon and modified three complex activities from constructivist professional development workshops for use in classroom and district contexts. These three key activities---constructing aesthetic texts, creating case studies, and building learning communities in order to effect cultural change---were consciously experienced and unpacked by these teacher-leaders during constructivist professional development, then re-imagined for use in new contexts. In each case, the microcosmic activity---whether writing, reading, getting to know one's learners, or building a learning community---may become metaphoric for what is possible in the macrocosm. I note that these teacher-leaders are consistently drawing upon five major theoretical bases: critical literacy, cognitive psychology and linguistics, anthropology, narrative theory, and teacher research itself. I also reflect on my role as mentor of teachers who are becoming leaders, discussing the importance of scaffolding for reciprocity: providing temporary structures and models until teacher-learners can act independently and confidently, and using the questions teacher-learners pose as paths to deeper inquiry.

A primary goal of culturing photosynthetic cells of higher plants in suspension is to induce the synthesis of edible primary metabolites such as proteins and carbohydrates by carbon dioxide fixation. A photosynthetic cell line of Glycine max (Soybean) was studied to optimize the photosynthetic biomass yield for purposes of a contained ecological life support system. The initial research focused on establishing a consistent and stable cell line and studying the fundamental cell growth characteristics upon subculture. These experiments established a requirement for a 10% inoculum size (v/v) containing conditioned media for sustained cell viability. The cell line was also investigated for tolerance to changes in auxin, cytokinin and sucrose concentration and proved to sustain changes of up to 20% in all three without adverse effects on photosynthetic cell growth. The major thrust of the research centered on studying the cell pH profile which exhibited an oscillatory pattern. The oscillation in pH was linked to the consumption of ammonium and nitrate ions in the medium, but resulted in the loss of cell viability when the cells were grown on MS medium containing ammonium or nitrate ions singly. A study to determine the cause of cell death established that the acidification experienced under ammonium--only conditions caused a reduction proton transport out of the cell and hence a reduction in ammonium ion flux into the cell. This antiport shut-down led the cells to experience nitrogen starvation and lose viability. The death of the cells grown on nitrate only was determined to be a function of prolonged exposure to high pH resulting in cell wall lysis. This project, though addressing problems of a contained ecological life support system, has important applications in agriculture and the fundamental study of photosynthesis and plant cell growth. Photosynthetic cell lines are the closest models to whole plants and can therefore be used to study whole plants in vitro. Other applications for this work include: protein production (chloroplast specific products), oxygen regeneration via carbon dioxide fixation, and the efficient micropropagation of plants by somatic embryogenesis.

Since the earliest contacts between Europe and North America, Indians have been represented by Europeans and their colonial descendants in music and imagery. Beginning in the late 1880s, Indian compositions in the art music repertoire increased in frequency, paralleling interest shown in Native cultures by American ethnologists, whose research made transcribed Indian melodies and oral texts more readily available. Composers used these melodies and texts in an attempt to create an American national music, authentic in its foundation within indigenous repertoires, but problematic with its use of these materials without an accompanying cultural sensitivity. And although direct quotation of Native melodies became less common after 1925, composers have continued to draw from indigenous cultures by means of appropriating oral texts, historic figures, and ritual forms through the present day. Beginning with the assumption that all forms of appropriation or borrowing by one culture from another are not identical, composers and their works are presented and classified using a framework derived from the semiotic analysis of Charles Sanders Peirce (1839-1914). Three categories, iconic, indexical, and symbolic are defined, and musical examples from each are discussed, including works by Burton, Cadman, Busoni, Coleridge-Taylor, Carter, and Oliveros. In addition, art music by a Native North American composer, Louis Ballard, is examined, and his use of Indian melodies compared to that of non-Indian composers.

Detailed light requirement for photosynthesis and cell growth can be evaluated using solid state light technology. Advanced gallium aluminum arsenide light-emitting diodes (LEDs) were examined for their ability to support mass culture of a unicellular eucaryotic green alga, Chlorella vulgaris. LEDs with peak emittance of 680 nm were used as a sole light source for cultivation. The final biomass and specific cellular growth rate under LEDs were comparable to those obtained under full spectrum from a fluorescent light (FL). The narrow spectrum monochromatic red light was found to affect the average cell volume (reducing it from 60 $\mu$m$\sp3$ to 30 $\mu$m$\sp3$), and make the size distribution and the per cell DNA distribution narrower, but did not affect the total biomass production. Based on two parametric flow cytometric analyses, it was found that the cells grown under red LED light had rather uniform amounts of DNA in all cell sizes, unlike those grown under FL. This result implies that the critical cell size for division under red light may be smaller than that under white light. A novel photobioreactor (PBR) system using the LEDs was designed and constructed. Direct internal illumination by 680 nm LEDs could deliver as high as 50 mW$\cdot$cm$\sp{-2}$ of light into the culture medium. Gas transfer by internal sparging had the capacity to transfer up to 1 mol O$\sb2{\cdot}$L$\sp{-1}{\cdot}$hr$\sp{-1}$. Nutritional and biological limitations could be overcome by continuous perfusion. When the PBR operated with a continuous perfusion rate of 6 reactor volumes a day, it could support ultra high-density algal cultures up to cell concentrations of 4$\cdot$10$\sp9$ cell$\cdot$mL$\sp{-1}$ and total biomass of 9.4% v/v (about 25 g$\cdot$L$\sp{-1}$ dry weight). The volumetric productivity was 3.15 g dry weight$\cdot$L$\sp{-1}{\cdot}$day$\sp{-1}$ (or 44 g dry weight$\cdot$m$\sp{-2}{\cdot}$day$\sp{-1}$). The oxygen production rate at its peak was 13-15 mmol$\cdot$L culture$\sp{-1}{\cdot}$hr$\sp{-1}$. This performance represents the highest reported cell densities attained in photoautotrophic cultures. Continuous perfusion allowed for long-term stable oxygen production. All the limiting factors in PBR design were discussed and analyzed for their characteristics. The data presented here demonstrates that PBR technology can be significantly improved and will provide a basis in future PBR designs.

Since health is closely related to sociocultural factors, a simple application of measures of health devised in Western developed countries to different societies might misrepresent reality. The aging of the population in developing countries adds to the importance of examining concepts and measures of health for their aged population within their particular sociocultural contexts. In addressing these issues, this dissertation examined a model of physical health for the elderly in Malaysia, the Philippines, Korea, and Fiji by using structural equation modeling technique. The evaluated model was further explored for its similarities and differences across these four cultures. This study identified chronic condition, functional limit, and self-evaluated health as three major dimensions of physical health across the cultures studied. Age, gender, education, and marital status explained less than 2.5% of the variance of chronic condition. These factors together explained from 21.7% to 26.9% of the variance of functional limit, while about one third to one half of the variance of self-evaluated health was explained by all these factors. The effects of the sociodemographic factors on each dimension of physical health were only partly supported with sampling variability in some instances. Across the four cultures, older elderly experienced more functional limit than their counterparts. More educated elderly had better self-evaluated health after controlling for the other dimensions. The effects of marital status on functional limit and self-evaluated health were not significant in all four cultures. Cross-cultural comparisons revealed different patterns of defining each dimension of physical health between the four cultures except between the Korean and the Fijian elderly. Inequivalent structural coefficients between the dimensions indicate that no two cultures shared the same causal process. The sociodemographic effects on each dimension were similar between the Korean and the Fijian elderly only. The findings from cross-cultural analysis support the belief that physical health is strongly associated with sociocultural factors. Since there are cultural differences in the effects of being older, being a woman, and being educated on physical health, transferring evaluations of physical health among the elderly to other societies is not justified without careful examination of sociocultural contexts.

Data from a sample of 104 Jews and 115 Polish Roman Catholics were used to investigate whether a devout religious upbringing yields significant benefits to the individual. The Religion Personality and Mental Health Project examined the relationship between religious observance and various aspects of personality, namely: neuroticism, psychoticism, dispositional happiness, obsessionality, psychological-mindedness, extraversion and locus of control. Previous research had shown that only psychoticism and happiness were consistently, significantly associated with religiosity, with more religious individuals better off in each case. It was hypothesized that inconclusive findings in previous research on other personality factors may have largely resulted from inattention to cultural and religious differences between groups. The present study thus focused on specific religious and ethnic populations. As predicted, more religious Jews and Catholics were significantly happier, less likely to have psychotic personality tendencies, and more likely to hold external control beliefs than non-religious participants. There was no significant relationship between religiosity and neuroticism. There were some indications that more religious subjects were less obsessional and less psychologically-minded. As predicted, differences on extraversion were attributable to ethnicity, not religiosity. Attempts to examine these relationships with a Lebanese Shiite population proved unsuccessful due to recruitment problems. Analyses indicated that the project's own locus of control measure was effective for use with religious, but not non-religious, populations. These results are discussed in connection with the importance of religion as a social factor, the role of existential certainty in mental health, and the centrality of religious and cultural differences in research on religion.

The subjects of the dissertation are genres and communication across cultures. These issues are explored within the Colonial context and at the level of discursive formation. Bernardino de Sahagun's Colloquios y doctrina cristiana (1564) which recounts the 1524 discussions between Franciscans and Nahuas serves as textual example. By examining the genres of which the text is comprised and the way in which it is structured, the attempt is made to discover how the text was constructed across cultures as well as the theory of intercultural communication which makes that construction possible. The proposed discursive analysis is grounded in Renaissance and Amerindian notions and practices of genre as well as Bakhtin's work on types within the context of human communication. Conversely, the text frames and leads to insights into issues of genre, the Colonial text and discourse across cultures. The proposed study is organized in the following way. Chapter One considers missionary goals and educational practices in Colonial Mexico while Chapter Two focuses on how the clergymen attempted to communicate God's message through their catechetic writings. A theory of intercultural communication is revealed in these works in the use of the voice, image, and body in conjunction with the letter. A review of critical literature in the third chapter begins the study of the Colloquios. The fourth chapter analyzes the genres used to construct the text--dialogue, sermon and huehuetlatolli. The issues of genre and intercultural communication come together in the final chapter in the exploration of how the three forms function in the Colloquios and why they were chosen for the text. By exploiting the generic features of dialogue and its position as the written form of a conversation, Sahagun blends the three across cultures creating a new generic hybrid and revealing a major process in thinking about cross-cultural interaction.

To many of the American corporate elite, victory in World War II presented a key moment of managerial opportunity. Much of what was understood about the world had changed; much of what was hoped for was suddenly within reach. One aspiration of that elite was that postwar America be considered one of history's greatest civilizations. Before this could happen, one deficiency needed attention: Americans had to become cultured, had to understand the prominent role the performing arts could play in their lives. To reveal the utility of the architectural elite and the monumental architectural artifact to this culture-building project, this dissertation studies the actors, actions, and intentions of the American corporate elite which directed the design of America's Acropolis, the Lincoln Center for the Performing Arts in New York City. It focuses especially on Lincoln Center's Vivian Beaumont Repertory Theater, of which Eero Saarinen was the architect. Research methods included archival searches, interviews with individuals who worked in Eero Saarinen's office or worked on the Lincoln Center project, site visits, the consideration of interdisciplinary scholarly texts and numerous popular texts, and attendance at Lincoln Center performances. The Lincoln Center elite gave programmatic form to the cultural capital of the world by promoting the centralization of the performing arts and asserting a hierarchy that encompassed the opera and orchestra and other performing arts activities aimed at preempting potential rivals and suppressing opposition to the project. The Lincoln Center architectural elite followed suit by adopting the paradigm of an inward-turning cultural fortress model buttressed against the neighborhood, designing five formidable buildings dominated by the Metropolitan Opera House, and fashioning an aesthetic and formal language of power which unified the cultural campus and marked it as a key site of a great new American civilization. The makers of the Vivian Beaumont Repertory Theater, including Saarinen, did not reach such agreement: a main stage was designed which accommodated both proscenium and thrust productions, compromising both; and a controversial temporary theater was built in Greenwich Village. In time, these disagreements led the Lincoln Center directorate to intervene and re-organize both the repertory theater elite and the architecture. In revealing a robust transactional setting inhabited by constellations of brokers, key men, and prime movers, this dissertation challenges the architectural field's reliance upon exclusive characterizations of clients, patrons, and architects. Instead, it analyzes a multivalent and multi-layered corporate elite which directed the architectural design process and an architectural elite to give form to their vision of a dominant, historically significant postwar America.

2-Methoxyethanol (ME), a widely used solvent, has been regarded as potentially toxic and causes adverse reproductive effects in animals. 2-Methoxyacetic acid (MA), the toxic metabolite of 2-methoxyethanol has been associated with infertility and depletion of spermatocytes in laboratory animals. The purpose of this research is to elucidate the mechanism of action of MA in male rat testicular culture cells. Sertoli cells, somatic cells in the seminiferous tubules, provide both structural and functional support for the developing germ cells. Hence, agents that affect the structure or function of Sertoli cells could impair the process of spermatogenesis. Therefore, the effect of 2-methoxyacetic acid on the metabolism of primary cultures of Sertoli cells, germ cells and Sertoli germ cell co-cultures prepared from rat testis was studied. MA at the concentration of 3 mM was found to stimulate glycolysis, glucose uptake and lactate metabolism in rat Sertoli cells. The increase in carbohydrate metabolism coincides with the stimulation of mitochondrial activity which was represented by the increase in polarization of mitochondrial membrane as indicated by Rhodamine 123 and increased MTT (a tetrazolium salt) reduction. The effect of MA on glycolysis suggested that the ATP utilizing system may be the other target of MA. Testicular cytoplasmic or plasma membrane ATPase was inhibited to 85% control but not mitochondrial ATPase. No changes in ATP concentrations were detected in Sertoli cell cultures. MA decreased 3(H) -thymidine incorporation in co-culture of Sertoli and germ cells even though germ cells in a co-culture environment survive, divide and are more tolerant of MA than germ cells in culture alone. Detachment of germ cells from Sertoli cells in 24 hour co-cultures occurred when incubated with 5 mM MA for 24 hours. Rates of LDH release from culture cells suggested that germ cells may be more sensitive MA than Sertoli cells. It is concluded that the detrimental effect of MA on germ cells may be attributed to a direct cytotoxic effect of MA on germ cells. The cytotoxicity may be the result of reduction of DNA synthesis, mitochondrial function, and alteration of carbohydrate metabolism.

Replicative DNA synthesis and mitosis are restricted to the basal cell layer of newborn rat epidermis. Suprabasal cells have withdrawn from the cell cycle and are in sequential stages of keratinization. Since suprabasal cells contain a diploid or less content of DNA, withdrawal from the cell cycle must be a postmitotic event. Nothing is known about the mechanism which prevents replicative DNA synthesis in the suprabasal cells of newborn rat epidermis. However, these cells are known to contain an activity that inhibits replicative DNA synthesis in the basal cell layer. This activity may also function to prevent replicative DNA synthesis in the suprabasal cells. The objective of this study was to isolate inhibitors of replicative DNA synthesis from newborn rat epidermis. The strategy for this study was to assay epidermal extracts for inhibitors of DNA synthesis in primary cultures of newborn rat keratinocytes. DNA synthesis was measured as the incorporation of ('3)H-TdR into acid precipitable material. The low molecular weight fraction, LMWF (less than 10Kd), of an aqueous epidermal extract was found to contain activity that inhibits replicative DNA synthesis in primary cultures. The inhibitory activity of the LMWF was detected in a novel assay utilizing primary cultures that were synchronized at the G1/S boundary with the DNA polymerase alpha inhibitor, aphidicolin. Cultures were exposed of LMWF during the synchronization procedure. Both the dose and duration of exposure of LMWF were varied. Replicative DNA synthesis was measured after the removal of the synchronization medium. LMWF caused a dose dependent inhibition of replicative DNA synthesis as measured by the incorporation of ('3)H-TdR into acid precipitable material. The magnitude of the inhibitory effect for a given dose of LMWF was dependent upon the duration of exposure to that dose. LMWF had no appreciable effect upon the incorporation of ('3)H-TdR into acid soluble material. Incubation of LMWF with carboxypeptidase A decreased its inhibitory effect about 2 and 1/2 fold. The results presented in this investigation suggest that newborn rat epidermis contains a small polypeptide factor that inhibits replicative DNA synthesis in primary cultures of newborn rat keratinocytes.

Photobioreactors (PBRs), capable of producing high density microalgal cultures are imperative for economical and effective utilization of microalgae and its products. The four major factors to be considered for the design of closed PBRs are light source and delivery, gas supply and exchange, nutrient supply, and removal of harmful secondary metabolites. The two latter issues, which are critical in obtaining high biomass concentrations, are addressed in this thesis. Specifically, this thesis addresses (i) the effects of the presence of conditioned medium on high-density cultures and (ii) the nutritional requirements of high-density microalgal cultures. Conditioned medium (CM) from high density cultures obtained from PBRs were tested for cell cycle and inhibitory activity. Low initial cell density cultures in presence of CM showed an accumulation of cells with two and four DNA equivalents, signifying a blockage of cell-division. Further, the culture pH increased by four units due to the presence of a high concentration of bicarbonate in the CM. Adding similar bicarbonate concentrations to fresh medium (FM) was found to increase the culture pH in an analogous fashion to CM cultures, causing blockage of cell division. The bicarbonate-free CM cultures at low (0.03%) CO$\sb2$ levels did not show any unusual cell cycle effects. CM cultures at high (5%) CO$\sb2$ levels supplemented with 100% FM components did not show any difference in growth and DNA content per cell distribution compared to 100% FM cultures. Further, experiments showed that there were no factors in the CM which were specific to cells in high density cultures. Taken together, these results lead to the conclusion that CM from high density cultures do not contain autoinhibitory or cell cycle modulating compounds that affect C. vulgaris in PBRs. N-8 medium, commonly used for culturing Chlorella, was evaluated for its capacity to support high density cultures on the basis of the elemental composition of Chlorella. It was found that the N-8 medium was depleted of iron, magnesium, sulfur and nitrogen at high cell densities. N-8 medium was redesigned to contain stoichiometrically balanced quantities of all the elements, to support a biomass concentration of 2% (v/v). Cultures in redesigned medium (named M-8 medium) showed significant enhancement in biomass production and chlorophyll content. The viability of the cultures increased two-three times and the medium demonstrated the capacity to sustain long-term high density viable microalgal cultures. Thus, high density C. vulgaris cultures can be achieved in PBRs with the use of proper medium and without performing ultrafiltration. This thesis underlines the significance of nutritional effects in high cell density cultures and the importance of medium development in the enhancement of PBR performance.

Man's prime interest is man. This interest has been and still is the prime mover in all that man does. For no matter what his method, he is ultimately seeking to solve the riddle of himself. It is imperative that he obtain this information so that he may be better able to direct himself in the fulfillment of his being. Thus, it is the connate objective of all men, in their own diverse ways, to seek the essence, the 'ding an sich, that which makes man man. In this search many efforts have been and are still being made. Each individual feels that his is the correct method, and so far as he does, he directs his devotion with more or leas fervour. So some men can be seen dismembering the bodies of the deceased down to the minutest cell, others testing and compounding chemicals and elements, while others seek the solution of the why and wherefore of the human machine in other actions of nature.