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Community valuations, perceptions, and judgments of eucalyptus plantation impacts in Ubajay and La Criolla, Entre Ríos, Argentina
Get PDFThe cultivation of tree plantations and subsequent expansion has become prevalent in Argentina over the last two decades due to incentive laws that support the plantation forestry industry. Two towns in the northern Pampas region of Argentina, Ubajay and La Criolla, were selected as study sites for determining community member valuations, perceptions, and judgments regarding the local plantation industry and its effects on the environment and economy. These sites were selected for their differing land use compositions, traditional land uses, and historical employment. Ubajay, a community with significant historical eucalyptus plantation land coverage and forestry employment, and La Criolla, a mixed use community with an economy traditionally focused on citriculture that is currently experiencing a shift to include a greater focus on plantation forestry. Survey data was collected from community members regarding importance of ecosystem services in and around their community, capability of eucalyptus plantations to provide desired ecosystem services, environmental and socioeconomic impacts caused by eucalyptus, and support for the plantation industry. Survey responses were analyzed to determine what aspects of the survey served as the best predictors for support for eucalyptus expansion. To follow up on these findings regarding individual’s beliefs about eucalyptus impacts and their malleability based on information provision, Interactive Community Fora were conducted in both communities in December 2017. These Interactive Community Fora provided participants with results from an interdisciplinary research study focused on the environmental impacts of eucalyptus plantation forestry that the two communities participated in over the last five years as well as the opportunity to engage in discourse regarding the local plantation industry and its impacts. It was found that participants in both communities acknowledged negative environmental impacts caused by eucalyptus once exposed to research findings; however, Ubajay was more resistant to acknowledging the severity of impacts than participants in La Criolla. Ubajay participants remained optimistic about socioeconomic effects of eucalyptus and support for the plantation industry, while La Criolla participants did not acknowledge strong socioeconomic benefits, and their support for the plantation industry declined over the course of the Interactive Community Forum. This deeper level of community engagement with scientific results provides a strong compliment to survey data where the perceptions behind views held toward land use change and its effects may not be as discernible for researchers. Results of this project have implications for the future expansion of plantation forestry in the region and what economic and environmental tradeoffs pertaining to the local forestry industry are acceptable for community members
Mapping the Thermal Inertia of Phobos using Thermal Infrared Spectra and Thermophysical Modeling
Get PDFWe present a map of the thermal inertia of Phobos, the larger of Mars' two moons, based on observations collected by Mars Global Surveyor (MGS) using the Thermal Emission Spectrometer (TES) instrument. We compare these observations with an existing airless body thermophysical model that was modified for Phobos. By comparing brightness temperature spectra derived from our TES observations with simulated spectra generated by our thermophysical model, we can constrain the thermal properties of Phobos' surface. One such property, thermal inertia, describes how well a surface resists changes in temperature over time. Thermal inertia is controlled by the physical characteristics of that surface, such as
the particle size.
Using 10 micron measurements, we derive an average thermal inertia of 42.0 +/- 13.6 J m^-2 K^-1 s^(-1/2) for the observed region, with local variations ranging from ~ 20 - 60 J m^-2 K^-1 s^(-1/2). This is similar to the ~ 50 J m^-2 K^-1 s^(-1/2) thermal inertia of lunar regolith, composed primarily of fine dust.
The observations used in this work cover roughly one hemisphere of Phobos, centered on the trailing side of the moon as it orbits around Mars. Our results show a fairly uniform thermal inertia across the observed region, and are generally consistent with prior estimates that relied on disk-integrated observations and not the disk-resolved observations used in this work.
We provide a global description of the surface temperature of Phobos as it varies with time, applying our thermophysical model and assuming a uniform thermal inertia of 42 J m^-2 K^-1 s^(-1/2). This provides mission planners with a robust characterization of the thermal environment a spacecraft is likely to experience upon arrival at Phobos' surface
Remediation and performance in standardized testing: Accuplacer preparation and placement outcomes at a large community college
Get PDFThis dissertation examines the efficacy of a remedial education program on placement outcomes. Specifically, it asks whether exposure to a Preparing for ACCUPLACER Workshop in a large community college system impacts placement outcomes for students who have attended the workshop. While focused on a narrower pilot program, this question is answered within the broader theoretical context of the relevance of preparatory programs on performance on standardized tests, a locus that enjoys a long tradition of scholarship in education research. That is, do preparatory programs improve performance on standardized tests? Beyond this theoretical imperative, the research is also relevant to the question of educational access. Students who cannot score high enough on standardized tests but are placed in regular classes may encounter motivational problems, which may imperil perseverance and retention, and lead to school dropout. The dissertation explores the impact of test preparation by examining preparation in conjunction with other demographic and foundational factors known to impact performance, such as ethnicity, gender, grade point average (GPA), socioeconomic status (SES), age, and quality of school
16,000 years of paleoenvironmental change from the Lake Peters-Schrader area, northeastern Brooks Range, Alaska
Get PDFPaleoclimate reconstructions are essential to contextualize recent warming that is affecting the Arctic region faster than anywhere else on Earth. To better understand this rapidly changing landscape, I used sedimentological evidence from Lake Peters and Lake Schrader in the northeastern Brooks Range to infer changing environmental conditions over the past 16,000 years (16 ka). Across five core sites, distinct changes in the visual stratigraphy and physical sediment properties including sediment bulk density, organic-matter content, and grain-size distributions record changing environmental conditions. The oldest sediments accumulated rapidly and contain little organic matter, interpreted to represent a landscape dominated by glacial and paraglacial processes associated with the rapid upvalley retreat of glaciers. No robust evidence was found for a climate fluctuation concurrent with the Younger Dryas. A peak in organic-matter abundance between 12–10 ka is attributed to a maximum in Northern Hemisphere summer insolation and accords with other regional paleoclimate reconstructions. Following this, conditions appear to have become drier as indicated by sediments with high density and low organic content until 5 ka. Alternatively, these sediments could represent a glacial advance, but this is unlikely as regional evidence for cooler conditions is absent. From 5–2 ka, organic matter consistently increases in several cores and is attributed to increased river discharge, which carried terrestrial organic matter into the lakes, or to increased summer temperatures, which led to higher productivity, or both. After 2 ka, sediments increase in density and decrease in organic content, which suggests the growth of glaciers within the catchment. Moraine mapping and lichenometry confirm previous studies and accord with changes in lake sediments. Rhizocarpon geographicum thallus diameters on boulders located on the outermost moraine crest suggest the maximum Holocene glacial extent is associated with increased moraine frequency from elsewhere in the Brooks Range dating to 2.5–1.9 ka. New measurements from a distinct moraine crest from an additional valley show consistency within the basin and are likely associated with a regional increase in moraine frequency from 1.1–1.0 ka. Increased sedimentation rates and organic productivity in both lakes may record glacier retreat during the last century. This study provides a framework for future research and fills an important gap in paleoenvironmental records for the northeastern Brooks Range
Assessing Flagstaff’s local food system resilience: Recommendations for bringing social equity to the forefront
Get PDFFood in the US is controlled by a few companies that are putting profits over people and the environment. This dominant system is predicated on agriculture that uses large amounts of water while degrading the soil by using chemical pesticides and fertilizers. The increasing awareness of the downfalls of highly mechanized agriculture production has sprouted alternative food movements that focus on smaller production with environmental health a top concern. However, within the past several years these movements have been criticized for failing to consider social equity. Principles within agroecology, food security, food justice and food sovereignty aim to acknowledge the racial conditions of food access and health. The racial conditions of minority groups are ridden with disinvestment and violent histories that result in food deserts. Uncertainties associated with climate change will require a holistic approach to alternative food movements that balances environmental health and social equity.
The southwest particularly will see severe water shortages resulting in unknown consequences to the national and global food network. This threat calls for cities such as Flagstaff to become more self-sufficient in food production. Resilience theory situates this study in bringing together agroecology, food justice, food security, and food sovereignty in an analysis of Flagstaff’s local food system. This study aims to analyze the resilience of Flagstaff’s food system by looking at local growers and the organizations that are supporting them. My research identifies the need for supporting more distribution efforts to low-income groups in addition to the need of diversifying the growing community in general. The Hispanic and Indigenous groups within Flagstaff have been largely left out of the small growing community. If Flagstaff is to support more growers, these populations need to be considered both as producers and consumers. This research is limited by not looking at the community gardens within Flagstaff and recommends this in future research as little research has been done on food production in Flagstaff. The research has brought seven main recommendations for Flagstaff to increase food system resilience
Changes in teacher perception and practice which occur with the implementation of personalized learning using technology
Get PDFABSTRACT
CHANGES IN TEACHER PERCEPTION AND PRACTICE WHICH OCCUR WITH THE IMPLEMENTATION OF PERSONALIZED LEARNING USING TECHNOLOGY
In recent years, the influence of technology and educational legislation have generated a desire for a transformation in education. As schools strive to move from the traditional factory-like model of instruction in which students learn the same things at the same time and in the same way, personalized learning (PL) has emerged as a model of instruction to meet student needs. Students will move into life needing to make choices on how to set goals and objectives and solve problems successfully by finding and using the resources that are available. To prepare students for the future, classroom instruction and student learning should better match how it will be in the real world.
In the real world, jobs and activities are individualized and personalized. If the ultimate goal is to prepare students for the future, students need to know how to set goals, make choices, self-regulate, and persevere while creating an understanding and connection about the content that makes sense to the student in the world around them. Teachers need to be informed and prepared with the right tools and resources to meet student needs and be able to personalize instruction and learning to make it relevant and meaningful for students. For many teachers, they have had little to no exposure to directing instruction while personalizing learning, so the task is not a natural or easy one. While legislation and research are suggesting that PL is a model that will work in education, the shift in perspective can seem insurmountable when the traditional model has been the collective way of teaching and learning for decades.
This qualitative study was designed to explore the changes in teacher perspective and practice which occur with the implementation of PL while using technology as a platform to hold curriculum with students in a general education classroom. The researcher explored the knowledge and skills that are necessary to implement PL in the general education setting, the changes that have occurred as teachers have moved from a traditional model to a personalized model, along with the perceived successes and challenges regarding the implementation of PL while using technology as a tool.
The participants in this study were teachers from three different elementary schools in a large suburban school district. All of the teachers were in the first year of implementing a PL program in their classroom as a part of a grade level wide implementation at their school. The teachers participated in focus groups and then one-on-one interviews to express perceptions and share their own personal stories of implementing PL in the general education setting. The focus groups and interviews were recorded and transcribed before being analyzed. The findings were presented in table and narrative form.
The findings of the study identified the knowledge and skills the teachers perceive as necessary to implement PL, such as the teacher mindset, collaboration, content/standard knowledge, technology skills, training, student/teacher relationships, and management. The teachers shared stories to describe the changes that have occurred along with the perceived successes and challenges as teachers move to a PL model. The findings could be used to help other educators prepare for implementation of PL in their schools
Application of vehicle-based sensors assessing highway pavement conditions subject to extreme temperature variation
Get PDFThe technique of using vibration sensors to monitor pavement roughness has been expanding in pavement engineering. The primary objective of this study is to implement cost-effective vibration sensors to predict asphalt roughness and identify critical cracking locations. It has been an increasing discussion in industry whether temperature changes due to climate change will have considerable influence on infrastructure resilience and sustainability. The method presented here uses vehicle-based sensors to assess pavement roughness during extreme hot and cold temperatures in Phoenix, AZ. This project consisted of developing vehicle-based accelerometers and taking monthly road surveys for a year. Five sensors were mounted to a vehicle, four on the tires and one inside the car, as well a sixth smartphone sensor inside the car. This project covers collecting data at pavement temperatures from 40ºF - 150ºF. The analysis consists of converting accelerometer data into international roughness index values using Fourier transforms and using statistical analysis to verify a relationship between pavement temperature and accelerometer vibration. The results show that hot asphalt concrete temperatures increase the amount of observable accelerometer vibration from a vehicle. Sensors mounted near the tires showed to be more reliable than sensors inside the vehicle. This project demonstrates that accelerometer sensing technology is a cost-effective way to advance the day-to-day operations in highway pavement maintenance and management
Chiefs’ narratives of girls and their education in Malawi
No full textThis thesis engages in a discussion around the education of girls in Malawi. Despite government and non-governmental organizations interventions in girls’ education, the dropout rate continues to rise. Discriminatory cultural practices seem to be a contributing factor to this problem. In examining cultural narratives of chiefs, the research aims to find how such narratives are perpetuating girls’ attendance in schools. The research proposes that if chiefs begin to develop critical consciousness (Freire, 2000, 1974) by using authentic dialogue, they could begin to see the world of girls in relation to education differently.
In this project, I ask the question: What cultural narratives and practices do Malawian chiefs perpetuate that affect girls’ education? The findings come from literature review and interviews with chiefs in Traditional Authority Malili in Lilongwe District. I used narrative inquiry as my methodology in capturing the stories that the chiefs shared during the interviews. There were three main themes that emerged out of the chiefs’ narratives. Compared to the past, chiefs now prefer to initiate young girls because after initiation ceremonies most older girls drop out of school. The research also found that girls are trained for house chores while still young unlike boys because they are regarded as mothers of the home and in preparation for their future. Lastly, the research found that girls behavior has changed due to outside influences such as democracy, gambling and inappropriate films. This has led chiefs in believing that girls are stubborn and disrespectful and therefore leading to school dropout
Directive Use in University Classroom Discourse: Variation across Disciplines, Academic Levels, and Interactivity
Get PDFDirectives— “attempts by the speaker to get the hearer to do something” (Searle, 1976, p. 11)—are one of the recurrent speech acts in university classrooms (Barbieri, 2008; Garcia, 2004). Directives are used by the instructors to perform important functions, such as assigning homework and guiding class work. Previous research has revealed that ineffective use of directives can result in misunderstanding and difficulty in learning (Waring & Hruska, 2012); thus, it is important to explore the variety of use of directives and analyze how they are perceived by the students to examine their effectiveness. Despite the abundance of research analyzing directives in academic contexts (Garcia, 2004; Hwang, 2013; McAllister, 2014; Reinhardt, 2010), no studies, to this date, have investigated the use of directives and their pragmatic functions from the listeners’ perspective.
The present study explores the use of directives in academic lectures by triangulating structural and situational variation (i.e., discipline, levels of instruction, and level of interactivity) in directive use as predictors of perceived pragmatic force of directives (i.e., strength of obligation and imposition) in a large corpus of university lectures. The data in this study comes from a 1.2 million-word corpus of lectures sampled from the TOEFL 2000 Spoken and Written Academic Language corpus (T2K-SWAL, see Biber et al., 2002). Possible linguistic patterns of directives were identified by manually analyzing sample lectures from various situational contexts. Subsequently, five major structural types of directives (i.e., imperatives, obligation, intention, permission verbs, and directive vocabulary) were selected for the automatic analysis, according to their frequency and lexico-grammatical explicitness. Python scripts were used to automatically identify directive utterances with the five structural types and the 27 structural sub-types included. Structural variation of directives was analyzed in relation to three situational variables: (1) discipline (business, engineering, education, humanities, natural sciences, social sciences), (2) level of instruction (freshman/sophomore, junior/senior, graduate), and (3) level of interactiveness (low, medium, high). For the qualitative analysis, directives manually extracted from a 83,725 word sample of lectures from engineering and humanities in T2K-SWAL were coded for strength of obligation and level of imposition from university students’ perspectives. Structural variation of directives and situational features of the lectures were examined as predictors of the perceived strength of obligation and level of imposition of directives.
The results show that structural features of directives are better predictors of perceived strength of obligation and imposition, compared to the situational factors. The relationship between various structural types and the pragmatic force of directives is also explained by thorough qualitative investigations of discourse patterns in individual texts. In summary, this dissertation helps to improve our understanding of the use of directives in lectures and their effectiveness with respect to directives’ structural variance. Findings from this study can be used to train international teaching assistants to effectively use directives, with respect to disciplines, levels of instruction, and levels of interactivity of university lectures
Speaker and listener variability in the perception of non-native speech
No full textWith the ever-increasing demands for success in second language (L2) English speech, applied linguistics research has been critical to uncovering important characteristics for communication in a global world where non-native English speakers (NNSs) must interact with a variety of interlocuters in many different contexts (i.e., English as a second language (ESL), English as a foreign language, English as a lingua franca. Yet speaking skills, especially pronunciation, are known to vary greatly from one learner to another. Furthermore, the way in which listeners perceive non-native speech is also known to vary from one listener to another. Therefore, the success of the L2 speaker-listener interaction can be impacted by how speech is produced by the speaker and how speech is perceived by the listener. Focusing on this L2 speaker-listener interaction, the current dissertation accounts for sources of both speaker and listener variability vis-à-vis non-native speech. Speaker variability was explored through individual differences (IDs) of motivation, aptitude, anxiety, and language contact. Listener variability was investigated via a listener’s novice/trained status. Twenty NNSs in an ESL context were recruited. Data collected from the NNSs included a speech sample; survey responses for motivation, anxiety, and language contact; and production tests of non-word repetition. The speech samples were instrumentally analyzed for segmental deviations and measures of rate, pausing, stress, pitch, and intonation. Sixty native English-speaking listeners were divided into two groups of 30—a novice group who rated the non-native speech impressionistically, and a trained group who underwent evidence-informed, construct training and calibration. The novice group provided their impressionistic ratings using 5-point impressionistic scales for accentedness, comprehensibility, and intelligibility, and the trained listener group used evidence-based rubrics to rate the same speech criteria. For speaker variability, hierarchical multiple regression analyses showed that IDs predicted large portions of variability (50-86%) in segmental and suprasegmental performance. Motivation and aptitude were associated with higher-proficiency pronunciation performance, while anxiety had a debilitative effect. Non-interactive language contact had a positive effect on L2 fluency, while interactive language contact was associated with more monotonous speech patterns. IDs did not have a predictive effect on Dynamic Prosody, reinforcing the need for pronunciation instruction of pitch and intonation. For listener variability, differences in novice and trained listeners were compared using indices from Multi-Faceted Rasch Measurement (MFRM). While both groups rated accentedness most severely, novice listeners displayed fundamental deficiencies with respect to their rating behavior. Additional multiple regression analyses revealed that novice listeners’ ratings were influenced by smaller portions of trait-relevant variance, and overly influenced by fluency-related speech phenomenon. Finally, multiple regression analyses further confirmed the effect of IDs (motivation, aptitude, anxiety, and language contact) on speakers’ accentedness, comprehensibility, and intelligibility for both novice and trained listeners, with a consistent effect from motivation and aptitude. Implications of these results advance areas of L2 acquisition, pedagogy, speech perception, pronunciation, and assessment