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The emergence and scaling of division of labor in insect societies

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Division of labor, whereby different group members perform different functions, is a fundamental attribute of sociality. It appears across social systems, from simple cooperative groups to complex eusocial colonies. A core challenge in sociobiology is to explain how patterns of

Division of labor, whereby different group members perform different functions, is a fundamental attribute of sociality. It appears across social systems, from simple cooperative groups to complex eusocial colonies. A core challenge in sociobiology is to explain how patterns of collective organization are generated. Theoretical models propose that division of labor self-organizes, or emerges, from interactions among group members and the environment; division of labor is also predicted to scale positively with group size. I empirically investigated the emergence and scaling of division of labor in evolutionarily incipient groups of sweat bees and in eusocial colonies of harvester ants. To test whether division of labor is an emergent property of group living during early social evolution, I created de novo communal groups of the normally solitary sweat bee Lasioglossum (Ctenonomia) NDA-1. A division of labor repeatedly arose between nest excavation and guarding tasks; results were consistent with hypothesized effects of spatial organization and intrinsic behavioral variability. Moreover, an experimental increase in group size spontaneously promoted higher task specialization and division of labor. Next, I examined the influence of colony size on division of labor in larger, more integrated colonies of the harvester ant Pogonomyrmex californicus. Division of labor scaled positively with colony size in two contexts: during early colony ontogeny, as colonies grew from tens to hundreds of workers, and among same-aged colonies that varied naturally in size. However, manipulation of colony size did not elicit a short-term response, suggesting that the scaling of division of labor in P. californicus colonies is a product of functional integration and underlying developmental processes, rather than a purely emergent epiphenomenon. This research provides novel insights into the organization of work in insect societies, and raises broader questions about the role of size in sociobiology.

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2011

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Promoting meaningful uses of technology in a middle school

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Federal education policies call for school district leaders to promote classroom technology integration to prepare students with 21st century skills. However, schools are struggling to integrate technology effectively, with students often reporting that they feel like they need to power

Federal education policies call for school district leaders to promote classroom technology integration to prepare students with 21st century skills. However, schools are struggling to integrate technology effectively, with students often reporting that they feel like they need to power down and step back in time technologically when they enter classrooms. The lack of meaningful technology use in classrooms indicates a need for increased teacher preparation. The purpose of this study was to investigate the impact a coaching model of professional development had on school administrators` abilities to increase middle school teachers` technology integration in their classrooms. This study attempted to coach administrators to develop and articulate a vision, cultivate a culture, and model instruction relative to the meaningful use of instructional technology. The study occurred in a middle school. Data for this case study were collected via administrator interviews, the Principal`s Computer Technology Survey, structured observations using the Higher Order Thinking, Engaged Learning, Authentic Learning, Technology Use protocol, field notes, the Technology Integration Matrix, teacher interviews, and a research log. Findings concluded that cultivating change in an organization is a complex process that requires commitment over an extended period of time. The meaningful use of instructional technology remained minimal at the school during fall 2010. My actions as a change agent informed the school`s administrators about the role meaningful use of technology can play in instruction. Limited professional development, administrative vision, and expectations minimized the teachers` meaningful use of instructional technology; competing priorities and limited time minimized the administrators` efforts to improve the meaningful use of instructional technology. Realizing that technology proficient teachers contribute to student success with technology, it may be wise for administrators to incorporate technology-enriched professional development and exercise their leadership abilities to promote meaningful technology use in classrooms.

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2011

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Global bioethics: a descriptive analysis of the function of bioethics in health and medicine on a global scale

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This thesis explores concept of "global bioethics" in both its development as well as its current state in an effort to understand exactly where it fits into the larger field of bioethics. Further, the analysis poses specific questions regarding what

This thesis explores concept of "global bioethics" in both its development as well as its current state in an effort to understand exactly where it fits into the larger field of bioethics. Further, the analysis poses specific questions regarding what it may contribute to this field and related fields, and the possibility and scope associated with the continued development of global bioethics as its own discipline. To achieve this, the piece addresses questions regarding current opinions on the subject, the authorities and their associated publications related to global bioethics, and what the aims of the subject should be given its current state. "Global Bioethics" is a term that, while seen frequently in bioethics literature, is difficult to define succinctly. While many opinions are provided on the concept, little consensus exists regarding its application and possible contributions and, in some cases, even its very possibility. Applying ethical principles of health and medicine globally is undoubtedly complicated by the cultural, social, and geographical considerations associated with understanding health and medicine in different populations, leading to a dichotomy between two schools of thought in relation to global bioethics. These two sides consist of those who think that universality of bioethics is possible whereas the opposing viewpoint holds that relativism is the key to applying ethics on a global scale. Despite the aforementioned dichotomy in addressing applications of global bioethics, this analysis shows that the goals of the subject should be more focused on contributing to ethical frameworks and valuable types of thinking related to the ethics health and medicine on a global scale. This is achieved through an exploration of bioethics in general, health as a function of society and culture, the history and development of global bioethics itself, and an exploration of pertinent global health topics. While primarily descriptive in nature, this analysis critiques some of the current discussions and purported goals surrounding global bioethics, recommending that the field focus on fostering valuable discussion and framing of issues rather than the pursuit of concrete judgments on moral issues in global health and medicine.

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2011

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The human capital accumulation of young mothers: the relationship with father involvement

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This study utilized ecological theory and social exchange theory to examine how father involvement effects the human capital accumulation of young mothers. This study used data from a sub-sample of young mothers taken from the Healthy Families Arizona longitudinal evaluation

This study utilized ecological theory and social exchange theory to examine how father involvement effects the human capital accumulation of young mothers. This study used data from a sub-sample of young mothers taken from the Healthy Families Arizona longitudinal evaluation (N = 84). The participants in the sub-sample were between 13 and 21 years of age. Using a random effects regression model, it was found that father involvement negatively affects a young mother's school attendance over time. The probability of a mother attending school when the father is involved decreases by 12%. It was also found that for the average age mother (19 years of age), the probability of attending school decreases by 59% every additional year. Furthermore, for a mother with an average number of children (one child), every additional child she has decreases the probability of attending school by 24%. In addition it was found that for the average age mother (19 years of age) every additional year, the likelihood of being employed increases 2.9 times, and for a mother with an average number of children (one child) every additional child decreases the likelihood of employment by .88 times.

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2011

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Comparison of soil and vegetation properties using salt extractor and conventional soil amendments from irrigation with coal bed natural gas product water

Description

Coal bed natural gas (CBNG) production has become a significant contribution to the nation's energy supply. Large volumes of water are generated as a byproduct of CBNG extraction, of which this "product water" is relatively high in sodium. High sodicity

Coal bed natural gas (CBNG) production has become a significant contribution to the nation's energy supply. Large volumes of water are generated as a byproduct of CBNG extraction, of which this "product water" is relatively high in sodium. High sodicity reduces water quality and limits environmentally compliant disposal options for producers. Crop irrigation with CBNG product water complies with state and federal laws and is a disposal method that also provides a beneficial use to private landowners. However, this disposal method typically requires gypsum and sulfur soil amendments due to the high levels of sodium in the water, which can reduce soil infiltration and hydraulic conductivity. In this study, I tested a new product called Salt Extractor that was marketed to CBNG producers to ameliorate the negative effects of high sodicity. The experiment was conducted in the Powder River Basin of Wyoming. I used a random block design to compare the soil and vegetation properties of plots following application with CBNG product water and treatments of either Salt Extractor, gypsum and sulfur (conventional), or no treatment (control). Data was analyzed by comparing the amount of change between treatments after watering. Results demonstrated the known ability of gypsum and sulfur to lower the relative sodicity of the soil. Plots treated with Salt Extractor, however, did not improve relative levels of sodicity and exhibited no favorable benefits to vegetation.

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2011

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Molecular chaperones of the endoplasmic reticulum promote hepatitis C virus E2 protein production in plants

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Infections caused by the Hepatitis C Virus (HCV) are very common worldwide, affecting up to 3% of the population. Chronic infection of HCV may develop into liver cirrhosis and liver cancer which is among the top five of the most

Infections caused by the Hepatitis C Virus (HCV) are very common worldwide, affecting up to 3% of the population. Chronic infection of HCV may develop into liver cirrhosis and liver cancer which is among the top five of the most common cancers. Therefore, vaccines against HCV are under intense study in order to prevent HCV from harming people's health. The envelope protein 2 (E2) of HCV is thought to be a promising vaccine candidate because it can directly bind to a human cell receptor and plays a role in viral entry. However, the E2 protein production in cells is inefficient due to its complicated matured structure. Folding of E2 in the endoplasmic reticulum (ER) is often error-prone, resulting in production of aggregates and misfolded proteins. These incorrect forms of E2 are not functional because they are not able to bind to human cells and stimulate antibody response to inhibit this binding. This study is aimed to overcome the difficulties of HCV E2 production in plant system. Protein folding in the ER requires great assistance from molecular chaperones. Thus, in this study, two molecular chaperones in the ER, calreticulin and calnexin, were transiently overexpressed in plant leaves in order to facilitate E2 folding and production. Both of them showed benefits in increasing the yield of E2 and improving the quality of E2. In addition, poorly folded E2 accumulated in the ER may cause stress in the ER and trigger transcriptional activation of ER molecular chaperones. Therefore, a transcription factor involved in this pathway, named bZIP60, was also overexpressed in plant leaves, aiming at up-regulating a major family of molecular chaperones called BiP to assist protein folding. However, our results showed that BiP mRNA levels were not up-regulated by bZIP60, but they increased in response to E2 expression. The Western blot analysis also showed that overexpression of bZIP60 had a small effect on promoting E2 folding. Overall, this study suggested that increasing the level of specific ER molecular chaperones was an effective way to promote HCV E2 protein production and maturation.

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2011

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The impact of tutoring with a supplemental educational services model on intrinsic motivation and mathematical achievement

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The purpose of this study was to examine the impact of individualized afterschool tutoring, under federal Supplemental Educational Services (SES), on mathematical and general academic intrinsic motivation and mathematical achievement of at-risk students. The population of this study consisted of

The purpose of this study was to examine the impact of individualized afterschool tutoring, under federal Supplemental Educational Services (SES), on mathematical and general academic intrinsic motivation and mathematical achievement of at-risk students. The population of this study consisted of two third graders and five fourth graders from an elementary school in the Reynolds School District in Portland, Oregon. One participant was male. The other six were female. Six of the students were Hispanic, and one student was multiethnic. Students' parents enrolled their children in free afterschool tutoring with Mobile Minds Tutoring, an SES provider in the state of Oregon. The participants were given pre- and post-assessments to measure their intrinsic motivation and achievement. The third graders took the Young Children's Academic Intrinsic Motivation Inventory (Y-CAIMI) and the fourth graders took the Children's Academic Intrinsic Motivation Inventory (CAIMI). All students took the Group Mathematics Assessment and Diagnostic Evaluation (GMADE) according to their grade level. The findings from this study are consistent with the literature review, in that individualized tutoring can help increase student motivation and achievement. Six out of the seven students who participated in this study showed an increase in mathematical achievement, and four out of the seven showed an increase in intrinsic motivation.

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2011

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Bursera microphylla in South Mountain Municipal Park: evaluating its habitat characteristics

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ABSTRACT The elephant tree, Bursera microphylla, is at the northern limit of its range in central Arizona. This species is sensitive to frost damage thus limiting its occurrence in more northern areas of the southwest. Marginal populations of B. microphylla

ABSTRACT The elephant tree, Bursera microphylla, is at the northern limit of its range in central Arizona. This species is sensitive to frost damage thus limiting its occurrence in more northern areas of the southwest. Marginal populations of B. microphylla are found in mountain ranges of Central Arizona and are known to occur in the rugged mountain range system of the South Mountain Municipal Park (SMMP). Little is known of the distribution of this species within the park and details relevant to the health of both individual plants and the population such as diameter and number of trunks, height, and presence of damage have not been examined. This study was designed, in part, to test the hypothesis that favorable microhabitats at SMMP are created by particular combinations of abiotic features including aspect, slope, elevation and solar radiation. Data on abiotic factors, as well as specific individual plant locations and characteristics were obtained for 100 individuals. Temperature data was collected in vertical transects at different altitudinal levels. Some of these data were used in spatial analyses to generate a habitat suitability model using GIS software. Furthermore, collected data was analyzed using Matlab© software to identify potential trends in the variation of morphological traits. In addition, for comparative purposes similar information at one hundred computer-generated randomly chosen points throughout SMMP was obtained. The GIS spatial analyses indicated that aspect, slope, elevation, and relative solar radiance are strongly associated as major climatic components of the microhabitat of B. microphylla. Temperature data demonstrated that there are significant differences in ambient temperature among different altitudinal gradients with middle elevations being more favorable. Furthermore, analyses performed using Matlab© to explore trends of elevation as a factor indicated that multiple trunk plants are more commonly found at higher elevations than single trunk plants, there is a positive correlation of trunk diameter with elevation, and that canopy volume has a negative correlation with respect to elevation. It was concluded that microhabitats where B. microphylla occurs at the northern limit of its range require a particular combination of abiotic features that can be easily altered by climatic changes.

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2011

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Lesson study and the co-construction of pedagogical knowledge among secondary specialty teachers

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Teacher learning in the workplace is situated within a complex context involving the individual and multiple aspects of an educational organization. The present action research study uses a socio-constructionist inquiry lens to further research the local and multifaceted nature of

Teacher learning in the workplace is situated within a complex context involving the individual and multiple aspects of an educational organization. The present action research study uses a socio-constructionist inquiry lens to further research the local and multifaceted nature of professional learning in schools. The goal is to re-conceptualize professional development away from reductionist approaches that assume teacher practice can be isolated, packaged, and directly transferable into the classroom. The present study examines how lesson study can structure interdisciplinary professional learning to address the current gap in the literature regarding professional development of secondary specialty teachers. Five teachers participated in two lesson study cycles for a period of 13-weeks. This study focused on how teachers co-construct pedagogical knowledge and the extent to which they make changes to their practice. Using a sequential mixed methods research design, this study collected qualitative and quantitative data in three phases. In the initial phase, participants completed a demographical survey and shared a digital ethnography of their philosophy of teaching. Phase two consisted of video recordings for two lesson study cycles. Phase three involved a second survey and semi-structured interviews. Classroom observations were conducted during the first and last phase of the study. All qualitative data was analyzed inductively using open and thematic coding. Cross-case analysis was employed at the analysis stage to integrate data tools for the purpose of complementarity. Results suggest lesson study was an effective, job-embedded model that supports active and continuous professional development that is sustained and transferrable to the classroom. The type of disposition reported and displayed by teachers changed positively over time having transformational effects in the depth of relationships among teachers, increasing co-creation of pedagogical knowledge, and increasing reflectiveness. Teachers' level of openness to learning related to higher levels of effective practices implemented during lessons. Further research is needed to examine the ways in which teacher disposition influences professional learning when secondary specialty teachers engage in lesson study.

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2014

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A measure of goodness: art teacher identity as a measure of quality

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ABSTRACT This qualitative study examines how high school art teachers conceive of being a good art teacher. Motivated by my own experiences as an art teacher, I designed this study to add teachers' voices to the conversation surrounding quality in

ABSTRACT This qualitative study examines how high school art teachers conceive of being a good art teacher. Motivated by my own experiences as an art teacher, I designed this study to add teachers' voices to the conversation surrounding quality in education. My research design included a narrative strand and an arts-based strand. In the narrative strand, I interviewed and observed 12 high school art educators from a major city in the southwest. I conducted an autoethnographic reflection exploring my connection to the research topic and research process. In the arts-based strand I used fiber-arts to further understand my topic. I wrote this dissertation using a narrative approach, blending the traditional research format, voices of participants, and my autoethnographic reflection. I included the results of my arts-based approach in the final chapter. Findings suggest that the teachers in this study conceptualize being a good art teacher as a process of identity construction. Each of the teachers understood what it meant to be a good art teacher in unique ways, connected to their personal experiences and backgrounds. As the teachers engaged in identity work to become the kind of art teacher they wanted to be, they engaged in a process of identity construction that consisted of four steps. I propose a model of identity construction in which the teachers chose teaching practices, evaluated those practices, identified challenges to their identities, and selected strategies to confirm, assert, or defend their desired identities. The findings have implications for teachers to become reflective practitioners; for teacher educators to prepare teachers to engage in reflective practices; and for administrators and policy makers to take into account the cyclical and personal nature of identity construction. This study also has implications for further research including the need to examine the dispositions of art teachers, teachers' evolving conceptions of what it means to be a good art teacher, and the effect labeling teachers' quality has on their identity construction.

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2014