Matching Items (147)
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Description
Background
Obese Latino adolescents are disproportionately impacted by insulin resistance and type 2 diabetes. Prediabetes is an intermediate stage in the pathogenesis of type 2 diabetes and represents a critical opportunity for intervention. However, to date, no diabetes prevention studies have been conducted in obese Latino youth with prediabetes, a highly

Background
Obese Latino adolescents are disproportionately impacted by insulin resistance and type 2 diabetes. Prediabetes is an intermediate stage in the pathogenesis of type 2 diabetes and represents a critical opportunity for intervention. However, to date, no diabetes prevention studies have been conducted in obese Latino youth with prediabetes, a highly vulnerable and underserved group. Therefore, we propose a randomized-controlled trial to test the short-term (6-month) and long-term (12-month) efficacy of a culturally-grounded, lifestyle intervention, as compared to usual care, for improving glucose tolerance and reducing diabetes risk in 120 obese Latino adolescents with prediabetes.
Methods
Participants will be randomized to a lifestyle intervention or usual care group. Participants in the intervention group will attend weekly nutrition and wellness sessions and physical activity sessions twice a week for six months, followed by three months of booster sessions. The overall approach of the intervention is framed within a multilevel Ecodevelopmental model that leverages community, family, peer, and individual factors during the critical transition period of adolescence. The intervention is also guided by Social Cognitive Theory and employs key behavioral modification strategies to enhance self-efficacy and foster social support for making and sustaining healthy behavior changes. We will test intervention effects on quality of life, explore the potential mediating effects of changes in body composition, total, regional, and organ fat on improving glucose tolerance and increasing insulin sensitivity, and estimate the initial incremental cost effectiveness of the intervention as compared with usual care for improving glucose tolerance.
Discussion
The proposed trial builds upon extant collaborations of a transdisciplinary team of investigators working in concert with local community agencies to address critical gaps in how diabetes prevention interventions for obese Latino youth are developed, implemented and evaluated. This innovative approach is an essential step in the development of scalable, cost-effective, solution oriented programs to prevent type 2 diabetes in this and other populations of high-risk youth.
Created2017-03-16
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Description
Evolving Earth observation and change detection techniques enable the automatic identification of Land Use and Land Cover Change (LULCC) over a large extent from massive amounts of remote sensing data. It at the same time poses a major challenge in effective organization, representation and modeling of such information. This study

Evolving Earth observation and change detection techniques enable the automatic identification of Land Use and Land Cover Change (LULCC) over a large extent from massive amounts of remote sensing data. It at the same time poses a major challenge in effective organization, representation and modeling of such information. This study proposes and implements an integrated computational framework to support the modeling, semantic and spatial reasoning of change information with regard to space, time and topology. We first proposed a conceptual model to formally represent the spatiotemporal variation of change data, which is essential knowledge to support various environmental and social studies, such as deforestation and urbanization studies. Then, a spatial ontology was created to encode these semantic spatiotemporal data in a machine-understandable format. Based on the knowledge defined in the ontology and related reasoning rules, a semantic platform was developed to support the semantic query and change trajectory reasoning of areas with LULCC. This semantic platform is innovative, as it integrates semantic and spatial reasoning into a coherent computational and operational software framework to support automated semantic analysis of time series data that can go beyond LULC datasets. In addition, this system scales well as the amount of data increases, validated by a number of experimental results. This work contributes significantly to both the geospatial Semantic Web and GIScience communities in terms of the establishment of the (web-based) semantic platform for collaborative question answering and decision-making.
Created2016-10-25
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Description
Despite their low cost and high nutrient density, the contribution of eggs to nutrient intake and dietary quality among Mexican-American postpartum women has not been evaluated. Nutrient intake and dietary quality, as assessed by the Healthy Eating Index 2010 (HEI-2010), were measured in habitually sedentary overweight/obese (body mass index (BMI)

Despite their low cost and high nutrient density, the contribution of eggs to nutrient intake and dietary quality among Mexican-American postpartum women has not been evaluated. Nutrient intake and dietary quality, as assessed by the Healthy Eating Index 2010 (HEI-2010), were measured in habitually sedentary overweight/obese (body mass index (BMI) = 29.7 ± 3.5 kg/m[superscript 2]) Mexican-American postpartum women (28 ± 6 years) and compared between egg consumers (n = 82; any egg intake reported in at least one of three 24-h dietary recalls) and non-consumers (n = 57). Egg consumers had greater intake of energy (+808 kJ (193 kcal) or 14%; p = 0.033), protein (+9 g or 17%; p = 0.031), total fat (+9 g or 19%; p = 0.039), monounsaturated fat (+4 g or 24%; p = 0.020), and several micronutrients than non-consumers. Regarding HEI-2010 scores, egg consumers had a greater total protein foods score than non-consumers (4.7 ± 0.7 vs. 4.3 ± 1.0; p = 0.004), and trends for greater total fruit (2.4 ± 1.8 vs. 1.9 ± 1.7; p = 0.070) and the total composite HEI-2010 score (56.4 ± 12.6 vs. 52.3 ± 14.4; p = 0.082). Findings suggest that egg intake could contribute to greater nutrient intake and improved dietary quality among postpartum Mexican-American women. Because of greater energy intake among egg consumers, recommendations for overweight/obese individuals should include avoiding excessive energy intake and incorporating eggs to a nutrient-dense, fiber-rich dietary pattern.
Created2015-10-02
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Description
The growth rate hypothesis (GRH) proposes that higher growth rate (the rate of change in biomass per unit biomass, μ) is associated with higher P concentration and lower C∶P and N∶P ratios. However, the applicability of the GRH to vascular plants is not well-studied and few studies have been done

The growth rate hypothesis (GRH) proposes that higher growth rate (the rate of change in biomass per unit biomass, μ) is associated with higher P concentration and lower C∶P and N∶P ratios. However, the applicability of the GRH to vascular plants is not well-studied and few studies have been done on belowground biomass. Here we showed that, for aboveground, belowground and total biomass of three study species, μ was positively correlated with N∶C under N limitation and positively correlated with P∶C under P limitation. However, the N∶P ratio was a unimodal function of μ, increasing for small values of μ, reaching a maximum, and then decreasing. The range of variations in μ was positively correlated with variation in C∶N∶P stoichiometry. Furthermore, μ and C∶N∶P ranges for aboveground biomass were negatively correlated with those for belowground. Our results confirm the well-known association of growth rate with tissue concentration of the limiting nutrient and provide empirical support for recent theoretical formulations.
ContributorsYu, Qiang (Author) / Wu, Honghui (Author) / He, Nianpeng (Author) / Lu, Xiaotao (Author) / Wang, Zhiping (Author) / Elser, James (Author) / Wu, Jianguo (Author) / Han, Xingguo (Author) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor) / Julie Ann Wrigley Global Institute of Sustainability (Contributor) / School of Sustainability (Contributor)
Created2012-03-13
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Description
Nitrogen (N) and phosphorus (P) are important limiting nutrients for plant production and consumer performance in a variety of ecosystems. As a result, the N:P stoichiometry of herbivores has received increased attention in ecology. However, the mechanisms by which herbivores maintain N:P stoichiometric homeostasis are poorly understood. Here, using a

Nitrogen (N) and phosphorus (P) are important limiting nutrients for plant production and consumer performance in a variety of ecosystems. As a result, the N:P stoichiometry of herbivores has received increased attention in ecology. However, the mechanisms by which herbivores maintain N:P stoichiometric homeostasis are poorly understood. Here, using a field manipulation experiment we show that the grasshopper Oedaleus asiaticus maintains strong N:P stoichiometric homeostasis regardless of whether grasshoppers were reared at low or high density. Grasshoppers maintained homeostasis by increasing P excretion when eating plants with higher P contents. However, while grasshoppers also maintained constant body N contents, we found no changes in N excretion in response to changing plant N content over the range measured. These results suggest that O. asiaticus maintains P homeostasis primarily by changing P absorption and excretion rates, but that other mechanisms may be more important for regulating N homeostasis. Our findings improve our understanding of consumer-driven P recycling and may help in understanding the factors affecting plant-herbivore interactions and ecosystem processes in grasslands.
ContributorsZhang, Zijia (Author) / Elser, James (Author) / Cease, Arianne (Author) / Zhang, Ximei (Author) / Yu, Qiang (Author) / Han, Xingguo (Author) / Zhang, Guangming (Author) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor) / Julie Ann Wrigley Global Institute of Sustainability (Contributor) / School of Sustainability (Contributor)
Created2014-08-04
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Description
A large fraction of the world grasslands and savannas are undergoing a rapid shift from herbaceous to woody-plant dominance. This land-cover change is expected to lead to a loss in livestock production (LP), but the impacts of woody-plant encroachment on this crucial ecosystem service have not been assessed. We evaluate

A large fraction of the world grasslands and savannas are undergoing a rapid shift from herbaceous to woody-plant dominance. This land-cover change is expected to lead to a loss in livestock production (LP), but the impacts of woody-plant encroachment on this crucial ecosystem service have not been assessed. We evaluate how tree cover (TC) has affected LP at large spatial scales in rangelands of contrasting social–economic characteristics in the United States and Argentina. Our models indicate that in areas of high productivity, a 1% increase in TC results in a reduction in LP ranging from 0.6 to 1.6 reproductive cows (Rc) per km[superscript 2]. Mean LP in the United States is 27 Rc per km[superscript 2], so a 1% increase in TC results in a 2.5% decrease in mean LP. This effect is large considering that woody-plant cover has been described as increasing at 0.5% to 2% per y. On the contrary, in areas of low productivity, increased TC had a positive effect on LP. Our results also show that ecological factors account for a larger fraction of LP variability in Argentinean than in US rangelands. Differences in the relative importance of ecological versus nonecological drivers of LP in Argentina and the United States suggest that the valuation of ecosystem services between these two rangelands might be different. Current management strategies in Argentina are likely designed to maximize LP for various reasons we are unable to explore in this effort, whereas land managers in the United States may be optimizing multiple ecosystem services, including conservation or recreation, alongside LP.
Created2014-09-02
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Description
We studied the microbial community structure of pilot two-stage membrane biofilm reactors (MBfRs) designed to reduce nitrate (NO[subscript 3]–) and perchlorate (ClO[subscript 4]–) in contaminated groundwater. The groundwater also contained oxygen (O[subscript 2]) and sulfate (SO[2 over 4]–), which became important electron sinks that affected the NO[subscript 3]– and ClO[subscript

We studied the microbial community structure of pilot two-stage membrane biofilm reactors (MBfRs) designed to reduce nitrate (NO[subscript 3]–) and perchlorate (ClO[subscript 4]–) in contaminated groundwater. The groundwater also contained oxygen (O[subscript 2]) and sulfate (SO[2 over 4]–), which became important electron sinks that affected the NO[subscript 3]– and ClO[subscript 4]– removal rates. Using pyrosequencing, we elucidated how important phylotypes of each “primary” microbial group, i.e., denitrifying bacteria (DB), perchlorate-reducing bacteria (PRB), and sulfate-reducing bacteria (SRB), responded to changes in electron-acceptor loading. UniFrac, principal coordinate analysis (PCoA), and diversity analyses documented that the microbial community of biofilms sampled when the MBfRs had a high acceptor loading were phylogenetically distant from and less diverse than the microbial community of biofilm samples with lower acceptor loadings. Diminished acceptor loading led to SO[2 over 4]– reduction in the lag MBfR, which allowed Desulfovibrionales (an SRB) and Thiothrichales (sulfur-oxidizers) to thrive through S cycling. As a result of this cooperative relationship, they competed effectively with DB/PRB phylotypes such as Xanthomonadales and Rhodobacterales. Thus, pyrosequencing illustrated that while DB, PRB, and SRB responded predictably to changes in acceptor loading, a decrease in total acceptor loading led to important shifts within the “primary” groups, the onset of other members (e.g., Thiothrichales), and overall greater diversity.
Created2014-07-01
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Description
The importance of second language learning in today’s ever-increasing globalized world is becoming ever more paramount. Despite seeming trends which indicate aversion to globalization, the international phenomenon which describes the connection made between peoples and cultures, will only increase its influence in coming years. With the advances globalization has made,

The importance of second language learning in today’s ever-increasing globalized world is becoming ever more paramount. Despite seeming trends which indicate aversion to globalization, the international phenomenon which describes the connection made between peoples and cultures, will only increase its influence in coming years. With the advances globalization has made, it is becoming more important to learn and study foreign languages in order to keep abreast of this trend and not be left behind by globalization. Why electronic translation is not so viable in the long run (at least currently) is that culture and syntax are not things which can be simply ascertained via mediums such as application use. Due to the fact that advanced language proficiency is considered to be an integral piece towards stronger sentiments of “integration” (i.e. Syrian refugees integrating into EU and US) it is of more importance that increasing second language proficiency receives the adequate study and implementation to reflect a more cohesive globalized world. Accompanying this necessity is the simple fact that adult second language learners often struggle to overcome difficulty to the challenging yet rewarding task of learning and eventually mastering a second language.

To truly understand the difficulty some adult second language learners have with learning a second language it can be helpful to compare second language acquisition to how one naturally, and seemingly effortlessly in many cases, acquires their native language. How can a comparative analysis of how native speakers and adult second language learners each learn their first and second language respectively be successfully converted to a specific means of assisting adult second language learners achieve the highest level of possible fluency? In order to more accurately propose a viable solution to the overarching question, the following three questions have been proposed as a means to springboard into better understanding the nature of the main topic.
The points to consider while analyzing the main question throughout this analysis are as follows: How would it be best for an adult second language learner to achieve the same level off proficiency as a native speaker of a given language whom has been exposed to all of its intricacies since birth? At what point exactly is someone considered to have the same level of proficiency which a native speaker of a given language would have and how does that differ from being a heritage speaker? With the final supporting question being: What type of learning would be best suited in helping a heritage speaker (someone who learns a language in the home by virtue of their heritage) or adult second language learner to become highly proficient in a second language?
In order to propose a wide variety of integration between these questions with the conjoined purpose of answering the inquiry of this thesis, many different sources supporting each of the above questions will contain certain overlap, providing a clear basis for constructing a tri-fold argument in answering the thesis question as acutely as possible. In regards to the first question, the question of “proficiency” will be a subsection committed to understanding the nature of how language proficiency works and at what point (if ever) one can ever be considered “highly proficient” in a second language.

All three exploratory questions are compatible with a theory known as Critical Period Theory, a theory in linguistics proposed by Montreal neurologist Wilder Penfield, which states, “There is a critical age, before puberty, that one must learn language. If one has not learned to speak before puberty it is much more difficult, and sometimes impossible, to learn language and speak in a meaningful way.” The overlap which this method binds to Universal Grammar is a rather close-knit relationship. Research composed by certain linguists suggest that “children are born with a certain universal grammar wired into their brains.” This will be compared and cross-examined to a higher degree in a later section of the paper.

The importance of Universal Grammar in relation to Critical Period Theory cannot be overstated.  Universal Grammar in relation to the second language Critical Period Theory will help explain at which point, someone is considered to be a “native speaker” of a given language. The third question posed of how would it be best for heritage and second language learners to increase their proficiency in a second language really touches on both of these theories in regards to at which age someone is exposed to a specific language in addition to how Universal Grammar affects the development of second language acquisition. In the realm of perpetually working towards mitigating an answer to this analysis’s thesis, the connecting thread or “roter Faden”, as it is said in German, will be the integrative domain the above questions will have on arriving to a clearer understanding of the nature of how a comparative analysis of second language learners and mother-tongue speakers can expedite the language learning process of second language learners, using techniques of native speakers which they inherently pick-up.
Created2018-12
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Description
This study examined the type and frequency of questions asked by attorneys in cases of children alleging sexual abuse. Of interest was whether child age would affect the questions asked. The participants included 25 child witnesses testifying in criminal trials in Maricopa County over a recent ten-year period. Children were

This study examined the type and frequency of questions asked by attorneys in cases of children alleging sexual abuse. Of interest was whether child age would affect the questions asked. The participants included 25 child witnesses testifying in criminal trials in Maricopa County over a recent ten-year period. Children were placed into two groups: younger (five to seven-year-olds) and older (eight to nine-year-olds). Every question asked, and answer provided, during children's testimony, was systematically and reliably coded for the content of the interaction. Attorneys exhibited developmental sensitivity, varying the amount of question they asked across content areas by the age of the child. In addition, attorneys varied in what they asked about: the prosecution focused more on the plausibility of abuse, whereas the defense focused more on how others may have suggestively influenced the child's report. Both attorneys were equally concerned about the consistency of narratives. The findings from the present study have direct policy implications for how attorneys structure their arguments, both in an attempt to establish, and question, children's credibility in these important cases. Keywords: children, age, suggestibility, consistency, inconsistency, plausibility
ContributorsHogan, Caitlyn Rose (Author) / Stolzenberg, Stacia (Thesis director) / Fradella, Hank (Committee member) / College of Public Service and Community Solutions (Contributor) / School of Criminology and Criminal Justice (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Description
Throughout history, terrorism has had major effects on tourists and tourism destinations that are targeted. When terrorists execute an attack in order to communicate a message, resulting impacts go far beyond lives lost. Included in these impacts is the fear that terror attacks leave on tourists, sometimes creating such an

Throughout history, terrorism has had major effects on tourists and tourism destinations that are targeted. When terrorists execute an attack in order to communicate a message, resulting impacts go far beyond lives lost. Included in these impacts is the fear that terror attacks leave on tourists, sometimes creating such an impression that tourists change travel plans as a result. Although there are many studies on destination image, risk perception, and decision-making, very few focus specifically on the millennial generation. Because millennials are changing the travel and tourism scene - as they now make up the largest percentage of the population \u2014 it is important for stakeholders in the tourism industry and DMOs to understand this shift and the implications that come with these changes. This study provides a qualitative analysis of millennials' views, attitudes, and beliefs regarding terror impacted tourist destinations. Specifically, it will explore how millennials develop their destination images, if millennials view international travel to be risky, and if millennials are willing to travel to terror impacted tourist destinations. Using focus group methodology, this study gathered data from students from a number of disciplines, genders, and travel experience, in order to understand the themes listed above. Analysis of the findings and implications for officials and DMOs follow, as well as a conclusion including limitations and recommendations for future studies.
Created2017-05