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A Mixed Methods Investigation of ESOL Teacher Advocacy: It's Not Going in and Just Teaching English
No full textIt is widely acknowledged that English language learners (ELLs) are a population in need of advocacy in K-12 public schools in the United States. The main professional standards for initial teacher certification call for English to speakers of other languages (ESOL) teachers to be advocates for ELLs. This mixed methods study investigates ESOL teachers' cognitions (beliefs, thoughts, attitudes; Borg, 2006) about advocacy and their actions as advocates. A survey of 511 ESOL teachers in five diverse school districts in one Mid-Atlantic state, and interviews with 15 of those teachers, confirm that ESOL teachers recognize the need for advocacy and have positive cognitions about advocacy. The ESOL teachers believe it is their professional responsibility to advocate, defined by those interviewed as monitoring for obstacles to ELLs' success, speaking up to raise awareness or inform others about ELLs and ESOL, providing resources or services, affirming ELLs' linguistic and cultural diversity, and empowering ELLs to self-advocate. This research found that most ESOL teachers engage in instructional advocacy, while fewer engage in political advocacy. Variables predictive of greater advocacy actions include belief in professional advocacy responsibility, knowledge of the standards, years of ESOL teaching experience, a supportive school context for advocacy, and self-efficacy in advocating. This study also points to the importance of the teacher education program in continuing to develop awareness of the need to speak up for ELLs and in preparing ESOL teachers with the skills needed for advocacy work. This dissertation proposes a framework for advocacy that identifies the intended recipients of ESOL teacher advocacy to be ELLs, ELL families, and ESOL teachers themselves, and highlights ESOL teachers' potential co-advocates to be ELLs, ELL families, general education teachers, school administrators, and community leaders. Finally, this study clarifies three overarching goals of advocacy: improving ELLs' educational outcomes, enhancing their life chances beyond the school, and challenging societal injustices that continue to make advocacy necessary. Future research could investigate how ESOL teachers who engage in instructional advocacy may also become involved in political advocacy for ELLs, and could probe the distinction between advocacy and activism for ESOL teachers and within the TESOL field
Topheavy and special Bishop-Phelps cones, Lyapunov rank, and related topics
No full textMotivated by optimization considerations, this dissertation investigates cones of the form C = cl(cone({1} x S)), where S is a non-empty arbitrary subset of R^{n-1}, as well as the corresponding completely positive cone K_C generated by C. First, we investigate the interrelations between S and C. Specifically, we show that many of the properties of the cone C are inherited from the underlying set S. With this realization, we determine which traits of S result in desirable properties for the cone C, such as pointedness, connected interior, etc. Further restricting our attention, we consider a special type of the cone C that reduces to the form {(t,x): t >= ||x|| }, where ||*|| is a norm on R^{n-1}. We show that cones of this type, which are called topheavy cones or special Bishop-Phelps (BP) cones, are always irreducible when n is greater than or equal to three. Defining the Lyapunov rank of a proper cone as the dimension of the Lie algebra of the automorphism group of the cone, in this dissertation, we show that the Lyapunov rank of any special Bishop-Phelps polyhedral cone in R^n, when n is greater than or equal to three, is one. We build on an earlier known result for the l_{1,+}^n cone (which is a special Bishop-Phelps cone with 1-norm) and show that any l_{p,+}^n cone, where p is between one and infinity but not equal to two, has Lyapunov rank one. In the last part of the dissertation, we study automorphisms of special Bishop-Phelps cones. In particular, we give a complete description of the automorphism group of the l_{1,+}^n cone as well as properties for the automorphisms of l_{p,+}^n cone. We also introduce the concept of conjugate pair preserving automorphisms on special Bishop-Phelps cones
PERCEIVED FAULTLINE IMPACT IN TEMPORARY DISTRIBUTED TEAMS: EXAMINING THE ROLE OF NORMS OF TECHNOLOGY USE
No full text As distributed teams are inherently heterogeneous, they have a greater tendency to fracture into subgroups which result from the misalignment of demographics, geography, or values of the team members. This is referred in the literature as a faultline. Current studies of faultline have focused on collocated teams, which differ from distributed teams in terms of their primary mechanism of interaction: face-to-face vs. computer-mediated. As distributed teams mainly rely on computer mediated communication, there is greater possibility of members making inaccurate and stereotyped impressions that can negatively affect them in working together as a team. Additionally, current faultline research has fixated on demographic attributes. Although these studies are insightful, there are other attributes that are more pertinent in influencing subgroups on distributed teams, specifically. This study extends the body of knowledge on faultline and distributed teams through the development of a model that systematically investigates antecedents of subgroup processes and team performance. The model was empirically tested with survey data collected from 225 graduate students in 53 distributed project teams, using Partial Least Squares method. Research results demonstrated several novel insights into how perceived faultlines impact team performances. Firstly, in temporary distributed teams, the alignment of time orientation attributes and relationship values, also known as dormant faultlines, are positively correlated with the sense of division among team members (a perceived faultine). Secondly, this perceived faultline is negatively related to perceived team performance through the presence of task and relationship conflicts. In other words, both relationship and task conflict mediated the relationship of perceived faultline and perceived team performance. Thirdly, while this perceived faultline negatively correlates with team performance, the norms of technology significantly moderate the negative relationship of task conflict on team performance. The results suggest that the negative relationship between task conflict and team performance was reduced in teams having higher norms of technology use for supporting task awareness, task coordination, and interactions. Finally, implications for research and practice are presented with potential avenues for future research. </bold
An Analysis of the Legality and Impact of Youth Curfew Laws on Criminal and Health-Related Outcomes
No full textUnderage alcohol consumption is a problem in the United States where nearly one-third of youth report first consuming alcohol before the age of 13. Currently, this amounts to at least 9.3 million underage drinkers. Although originally implemented to reduce youth crime (with mixed effectiveness) and not as a means of deterring underage drinking, juvenile curfew laws have had an effect on adolescents' behavior. These laws seek to provide general protection to youth and adults by restricting the times that children of certain ages are allowed to occupy public places or streets. These laws often contain exemptions, such as allowing youths to be accompanied by adults, to respond to an emergency, or to travel to or from school, work, or a religious service. This dissertation: (a) investigates the history of curfew laws in the United States and reviews the studies that have been done to date [Article 1]; (b) provides a legal analysis of cases involving curfew laws and offers guidance for how curfew laws can be drafted to avoid being overturned in a legal challenge [Article 2]; and, (c) examines whether curfew laws are effective at reducing underage alcohol consumption [Article 3]
The intersection between professional development and professional learning communities: Working towards improving the educational experiences of English learners
No full textThis research investigated professional development (PD) experiences of secondary teachers of English learners (ELs) in Maryland and their perceptions concerning characteristics of PD that are most effective in helping them to improve their professional knowledge and attitudes toward PD. It also investigated whether being part of professional learning communities (PLCs) enhanced PD outcomes by extending teachers' access to sustained learning. This inquiry fills a gap in research concerning PD experiences of teachers based on the analysis of school-based PLCs. This research integrated Garet et al.'s (2001) framework of effective PD and Olivier and Hipp's (2010) model of PLCs. The integration of these two frameworks highlights the reciprocal relationship between PD and PLCs, and the extent to which these experiences and structures generate changes in teachers' improved knowledge and attitudes toward PD. A mixed methods approach is implemented to analyze survey and interview data in a sequential manner with emphasis on the quantitative component. The study is built on the strength of both quantitative and qualitative research methods, and jointly, these methods provide a more complete picture of the research problem than would either method individually (Creswell, 2009). A total of 100 teachers participated in the survey and 9 teachers participated in the interview. The analysis supports and extends Garet et al.'s (2001) findings that PD that emphasized improving content knowledge and was coherent with teachers' other learning experiences resulted in teachers' positive attitudes toward PD, as well as perceived improvement in knowledge. The results also revealed key practices of teachers' PLCs. Teachers' PLCs focused on their professional growth and improvement of student learning while fostering leadership and engaging in school improvement were not strong components of their practices. As a result, the associations of PLCs and teachers outcomes were not significant. This study is significant because it contributes to the emerging knowledge base that explores the relationship between the effects of PD on teachers and the role of PLCs reinforcing in best practices. The results of this research inform educators and education policy regarding and provide deeper insight into the comprehensive conditions needed for improving teachers' PD and PLC experiences
Improving Access to Mobile Technologies Using Tactile Feedback
No full textMobile technologies offer the benefits of portability and ubiquity. However, their reliance on small visual displays and realistic settings (e.g. while on the move) can introduce a variety of usability challenges to users, causing situational-induced impairments and disabilities (SIIDs). While the sense of touch provides one solution to supporting users with SIIDs, the tactile feedback provided by current mobile technologies is relatively simple in nature, often based on the metaphorical associations arbitrarily dictated by interface designers. Furthermore, these cues are yet to be extensively evaluated outside of controlled environments. This dissertation aimed to address these limitations. Firstly, we studied the range of discernible tactile icons (tactons) that can be presented via standard mobile technologies. Findings highlighted the role of intensity in supporting tactile recognition as well as the impact of duration, interval and intensity on task time. We also examined the use of tactons in a mobile exertion application, designed to help individuals monitor and modify walking behavior. Usability tests of the application proved its utility in communicating alerts and promoting physical activity among users. Secondly, we examined the impact of situational distractors (i.e. sound and movement) on the perception of multi-parametered tactons. Results indicated the negative effects of these distractors on recognition accuracy, time taken and cognitive workload. However, some tactile designs (e.g. those encoded with stronger intensities) were found to be able to better resist such effects. Our findings highlighted the importance of evaluating mobile interfaces in more realistic contexts. Thirdly, we investigated the intuitiveness of tactile mappings between tactile parameters (e.g. intensity of vibrations) and message features (e.g. urgency of messages) for mobile notifications. A paired-comparison task was performed. Using this approach, we identified the tactile mappings rated with the highest preference scores. Tactons designed using these mappings were proved to be more effective in field-based settings. The dissertation has culminated in a set of design guidelines relating to the design and evaluation of tactons for use in mobile interactions. These guidelines may help the mobile interface developers to construct effective tactile feedback, and improve users' access to mobile technologies in distracting contexts
Novel proteomic tools to understand fungal cell wall development and repair
No full textFilamentous fungi of genus Aspergillus represent a good assortment of microbes having enormous value in the bioprocessing industry and those demonstrating pathogenic activity in either plants [3] or people [4]. Fungal cell wall proteins (CWPs) protect the cell against stressful conditions in a fermenter [1], control branching [2,3] and are promising antifungal drug targets [4]. To this end the broad goal of my research is to develop novel proteomic strategies to identify and quantify change in expression of proteins that play a formidable role in cell wall development and repair. To begin with we developed a procedure to extract cell wall proteins from isolated cell walls and identify them using shotgun proteomic workflows consisting of reverse phase liquid chromatography followed by tandem mass spectrometry (LC-MS/MS). In order to isolate cell walls we used sophisticated washing steps followed by two different approaches to extract CWPs from isolated cell walls which were then subjected to shotgun proteomics. Overall 34 nominal cell wall proteins were identified including proteins essential for cell wall integrity signaling (CWIS) and each step of cell wall biosynthesis. Next we established a tool to quantify changes in cell wall protein expression compatible with shotgun proteomic workflow using Deuterium Isobaric Amine Reactive Tag (DiART) reagents. DiART represents cost-effective isobaric tagging reagents due to incorporation of deuterium isotopes. We corroborated the feasibility of performing protein quantitation on a LTQ mass spectrometer using quantitative data obtained from DiART tagged synthetic peptides, model protein mixtures and complex cell wall proteins. Subsequently we proved the applicability of DiART for quantitative phosphoproteomic workflows using DiART tagged phosphopeptides subjected to affinity enrichment using TiO2 resins. Finally we focused our efforts on characterization of phosphorylation mediated regulatory networks in A. nidulans which would be valuable for overall fungal research. Using a bottom-up phosphoproteomic workflow and a state-of-the-art mass spectrometer Q-Exactive, we identified 1637 unique phosphopeptides from 647 phosphoproteins. Functional classification and kinase-substrate analysis collectively revealed clear association of the phosphoproteome and cellular events essential for fungal morphology and secretion. Overall our methodology could be used to quantify changes in cell wall protein expression and phosphorylation, both of which are inherently observed in CWIS
Comparison of Cloud Security Standards & Cloud Security control recommendation System
No full textCloud services are becoming an essential part of many organizations. Cloud providers have to adhere to security and privacy policies to ensure their users' data remains confidential and secure. On one end, cloud providers are implementing their own security and privacy controls. On the other hand, standards bodies like Cloud Security Alliance (CSA), International Organization for Standards (ISO), National Institute for Standards and Technology (NIST), etc. are developing broad standards for cloud security. In this paper we provide a comprehensive analysis of the cloud security standards that are being developed and how they compare with the security controls of cloud providers. Our study is mainly focused on policies about mobility of resources, identity and access management, data protection, incident response & audit and assessment. This paper will help consumer organizations with their compliance needs by evaluating the security controls and policies of cloud providers and assisting them in identifying their enterprise cloud security policies
Real-time Disaster Crisis Mapping based on Classification and Geo-location Recognition in Tweets.
No full textGenerally, one finds a large percentage of social media data, such as Tweets or Instagram, lack Geo-tagged location in their metadata, minimizing their use in generating Crisis Maps during natural and human caused disasters. In the following work, we will determine the 'at risk' areas for particular geographical locations(New York State for this current research) through post- disaster events such as Hurricane Sandy by the analysis of all tweets originating from the Geo-location area under consideration through exact string matching of location entities in tweet texts. In this study, we employ the 8 Million Twitter data set collected by Aulov, Price and Halem stored in Couch DB. We use a Named Entity Analysis algorithm, based on the Sultanik and Fink, to obtain locations of places mentioned tweets without geo -location tags, thus increasing spatial information relevant to developing real-time Crisis Maps of the affected disaster areas being impacted under hurricane events or other related extreme natural events. The algorithm for Geo-location recognition is based on forming N-Gram tokens extracted from text in the tweet which are further mapped against a location gazetteer to obtain the coordinates of the locations or places through exact string matching in the gazetteer. The location gazetteer contains key-value pairs of the name and alternate names of the places, belonging to New York State as 'key' and their coordinates as 'value'. Once all the locations are found, an augmented Crisis Map consisting of both Geo-tagged and inferred locations is shown to increase the observations of the impacted areas. We show that based on an increase in frequency of locations, `at-risk' areas can be distinguished from `impacted' areas
Female color preferences, ecological selection, and the evolution of male coloration in darters (Percidae: Etheostomatinae)
No full textSince Charles Darwin's initial observations and hypotheses, the evolution of elaborate male coloration in sexually dichromatic species has been the subject of great interest. Of particular recent interest is how sexual and ecological selection interact to shape variation in male coloration between closely-related species. Using darters (Percidae: Etheostomatinae), a group of fishes that vary in male coloration as a model system, my goal is to determine how sexual and ecological selection interact to shape variation in male coloration between as well as within species lineages. In Chapter 1, I used reflectance spectrophotometry to examine correlations between spectral properties of orange and blue pigmentation in the rainbow darter, Etheostoma caeruleum, with parasite load and observed a correlation between the chroma of orange bars with parasite counts. In Chapter 2, I quantified color preferences in the darter genus Etheostoma to determine if the strengths of attraction to different colors coincided with variation in male coloration between species. The females of most achromatic species exhibited no significant color preferences, while chromatic species varied in preferences, with a positive association between the presence of red or orange on the flanks and preference for red detected across all species. In Chapter 3 I utilized phylogenetic comparative approaches and a laboratory experiment of predator color preferences to quantify the role of ecological variables in shaping variation in male coloration in darters. Compared to achromatic species, chromatic darters tend to inhabit environments where predation risk would be lower; specifically, shallower, faster-flowing upland streams with a lower number of overlapping predatory species. Additionally, a common darter predator, largemouth bass (Micropterus salmoides), exhibited significant preferences for red stimuli in a color choice experiment. Finally, in Chapter 4 I investigated color and size correlations, as well as male and female preferences for different sized and colored mates, in the Roanoke darter, Percina roanoka. Using digital photography I found correlations between size and color, but no preferences for larger or more colorful mates were observed in either sex. The results of this dissertation suggest that sexual and ecological selection do interact to shape color variation between darter species