24 resultados para Portuguese as a non-native language


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This qualitative study is concerned with exploring the transcultural experiences of ESOL students and connecting their lived experiences to literature in the classroom. The purpose of this study was to describe and explain the transcultural perspectives of six high school and community college students: four Cuban born students and two American born/raised students of Cuban-American culture. The participants were from Barbara Goleman Senior High School and Miami-Dade Community College. The six phenomenological portraits were explored in the form of lived experience pieces, representing the students' transcultural experiences. The data was collected in the form of student interviews, researcher's journal, and document reviews. The following exploratory questions guided this study: (1) From the perspective of four Cuban-born, non-native English-speaking students (NNS), what are the essential structures of their transcultural identities? (2) What are the underlying themes that account for the Cuban NNS students' transcultural experiences? (3) What are the universal transcultural structures among the Cuban NNS students' transcultural experiences and the Cuban-American, native English/Spanish speaking (NESS) students' experiences? (4) What are the possible structural meanings of the Cuban NNS students' interests in relation to their transcultural experiences? (5) What are some connections between the structural themes inherent in the Cuban NNS students' transcultural experiences and teaching literature in ESOL? ^ A phenomenological approach was used to investigate the participants' transcultural experiences, focused on the students' lived experiences. The study consisted of three interview sessions for each of the six participants. The analysis of the data was conducted following the principles of qualitative research, which included participant interviews, thematic analysis, researcher's journal, document reviews, and triangulation. The researcher created portraits representing students' transcultural experiences. Subsequently, the participants' transcultural experiences were used to respond to the exploratory questions, including comparing and contrasting themes and drawing connections among teaching literature in the ESOL classroom. ^ The results of this study show some relevant specific statements and themes that emerged from the students' transcultural data. The results serve as a better understanding of these students' transcultural experiences and the potentiality of connecting their perspectives to literature in the classroom. In addition, this study shows the need for a better understanding of the connection between transcultural experiences and literature in ESOL. ^

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Most pharmaceutically relevant proteins and many extracellular proteins contain disulfide bonds. Formation of the correct disulfide bonds is essential for stability in almost all cases. Disulfide containing proteins can be rapidly and inexpensively overexpressed in bacteria. However, the overexpressed proteins usually form aggregates inside the bacteria, called inclusion bodies, which contains inactive and non-native protein. To obtain native protein, inclusion bodies need to be isolated and resolubilized, and then the resulting protein refolded in vitro. In vitro protein folding is aided by the addition of a redox buffer, which is composed of a small molecule disulfide and/or a small molecule thiol. The most commonly used redox buffer contains reduced and oxidized glutathione. Recently, aliphatic dithiols and aromatic monothiols have been employed as redox buffers. Aliphatic dithiols improved the yield of native protein as compared to the aliphatic thiol, glutathione. Dithiols mimic the in vivo protein folding catalyst, protein disulfide isomerase, which has two thiols per active site. Furthermore, aromatic monothiols increased the folding rate and yield of lysozyme and RNase A relative to glutathione. By combining the beneficial properties of aliphatic dithiols and aromatic monothiols, aromatic dithiols were designed and were expected to increase in vitro protein folding rates and yields. Aromatic monothiols (1-4) and their corresponding disulfides (5-8), two series of ortho- and para-substituted ethylene glycol dithiols (9-15), and a series of aromatic quaternary ammonium salt dithiols (16-17) were synthesized on a multigram scale. Monothiols and disulfides (1-8) were utilized to fold lysozyme and bovine pancreatic trypsin inhibitor. Dithiols (11-17) were tested for their ability to fold lysozyme. At pH 7.0 and pH 8.0, and high protein concentration (1 mg/mL), aromatic dithiols (16, 17) and a monothiol (3) significantly enhanced the in vitro folding rate and yield of lysozyme relative to the aliphatic thiol, glutathione. Additionally, aromatic dithiols (16, 17) significantly enhance the folding yield as compared to the corresponding aromatic monothiol (3). Thus, the folding rate and yield enhancements achieved in in vitro protein folding at high protein concentration will decrease the volume of renaturation solution required for large scale processes and consequently reduce processing time and cost.

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Novel predator introductions are thought to have a high impact on native prey, especially in freshwater systems. Prey may fail to recognize predators as a threat, or show inappropriate or ineffective responses. The ability of prey to recognize and respond appropriately to novel predators may depend on the prey’s use of general or specific cues to detect predation threats.We used laboratory experiments to examine the ability of three native Everglades prey species (Eastern mosquitofish, flagfish and riverine grass shrimp) to respond to the presence, as well as to the chemical and visual cues of a native predator (warmouth) and a recentlyintroduced non-native predator (African jewelfish). We used prey from populations that had not previously encountered jewelfish. Despite this novelty, the native warmouth and nonnative jewelfish had overall similar predatory effects, except on mosquitofish, which suffered higher warmouth predation. When predators were present, the three prey taxa showed consistent and strong responses to the non-native jewelfish, which were similar in magnitude to the responses exhibited to the native warmouth. When cues were presented, fish prey responded largely to chemical cues, while shrimp showed no response to either chemical or visual cues. Overall, responses by mosquitofish and flagfish to chemical cues indicated low differentiation among cue types, with similar responses to general and specific cues. The fact that antipredator behaviours were similar toward native and non-native predators suggests that the susceptibility to a novel fish predator may be similar to that of native fishes, and prey may overcome predator novelty, at least when predators are confamilial to other common and longer-established non-native threats.

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We present a framework for explaining variation in predator invasion success and predator impacts on native prey that integrates information about predator–prey naïveté, predator and prey behavioral responses to each other, consumptive and non-consumptive effects of predators on prey, and interacting effects of multiple species interactions. We begin with the ‘naïve prey’ hypothesis that posits that naïve, native prey that lack evolutionary history with non-native predators suffer heavy predation because they exhibit ineffective antipredator responses to novel predators. Not all naïve prey, however, show ineffective antipredator responses to novel predators. To explain variation in prey response to novel predators, we focus on the interaction between prey use of general versus specific cues and responses, and the functional similarity of non-native and native predators. Effective antipredator responses reduce predation rates (reduce consumptive effects of predators, CEs), but often also carry costs that result in non-consumptive effects (NCEs) of predators. We contrast expected CEs versus NCEs for non-native versus native predators, and discuss how differences in the relative magnitudes of CEs and NCEs might influence invasion dynamics. Going beyond the effects of naïve prey, we discuss how the ‘naïve prey’, ‘enemy release’ and ‘evolution of increased competitive ability’ (EICA) hypotheses are inter-related, and how the importance of all three might be mediated by prey and predator naïveté. These ideas hinge on the notion that non-native predators enjoy a ‘novelty advantage’ associated with the naïveté of native prey and top predators. However, non-native predators could instead suffer from a novelty disadvantage because they are also naïve to their new prey and potential predators. We hypothesize that patterns of community similarity and evolution might explain the variation in novelty advantage that can underlie variation in invasion outcomes. Finally, we discuss management implications of our framework, including suggestions for managing invasive predators, predator reintroductions and biological control.

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The purpose of this study was to delineate which demographic and school variables were important for predicting the achievement of 10th grade African-American students. The sample population was divided into two groups: high-achievers, students with GPAs of 3.5 or higher, and low-achievers, students with GPAs of 1.5 or lower. Variables examined in the study included: gender; birth place; student's native language; exceptionality (ESE); history of English proficiency (LEP); SES (lunch status) in elementary and high school; the percentage of the Black student population in high school; and suspensions, absences, tardies, and the Stanford Achievement Test (SAT) scores in reading comprehension, mathematics computation, and mathematics applications in elementary and middle school. Two separate logistic regression analyses were conducted to determine which variables were influential in predicting achievement.^ Analysis 1 (N = 366), which included all the variables, except the SAT percentile scores, correctly classified 87% of the students as high-achievers or low-achievers. The results from Analysis 1 revealed that students who--were female; spoke a language other than English as their first language; did not apply for free or reduced lunch in elementary school; were in the gifted program; had no absences or tardies in elementary school; had no suspensions or tardies in middle school; and attended a high school with a lower percentage of Black students--were more likely to be high-achieving than low-achieving.^ Analysis 2 (N = 274) included all the variables and resulted in 94% of the students being correctly classified. It was found that students who--were female; were currently or previously classified as Limited English Proficient (LEP); did not apply for free or reduced lunch in elementary school; had no suspensions or tardies in middle school; and had higher percentile scores in reading comprehension and mathematics computation on the SAT in middle school--were more likely to high-achieving than low-achieving.^ The quantitative analyses were coupled with interviews from a purposeful sample of the population (N = 12) to gain additional insight about why some African-American students are succeeding in our schools and others are not. This study provides a viable means for assessing African-American students' achievement patterns in our schools. ^

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Non-native fishes present a management challenge to maintaining Everglades National Park (ENP) in a natural state. We summarized data from long-term fish monitoring studies in ENP and reviewed the timing of introductions relative to water-management changes. Beginning in the early 1950s, management actions have added canals, altered wetland habitats by flooding and drainage, and changed inflows into ENP, particularly in the Taylor Slough/C-111 basin and Rocky Glades. The first non-native fishes likely entered ENP by the late 1960s, but species numbers increased sharply in the early 1980s when new water-management actions were implemented. After 1999, eight non-native species and three native species, all previously recorded outside of Park boundaries, were found for the first time in ENP. Several of these incursions occurred following structural and operational changes that redirected water deliveries to wetlands open to the eastern boundary canals. Once established, control non-native fishes in Everglades wetlands is difficult; therefore, preventing introductions is key to their management. Integrating actions that minimize the spread of non-native species into protected natural areas into the adaptive management process for planning, development, and operation of water-management features may help to achieve the full suite of objectives for Everglades restoration.

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Few valid and reliable placement procedures are available to assess the English language proficiency of adults who enroll in English for Speakers of Other Languages (ESOL) programs. Whereas placement material exists for children and university ESOL students, the needs of students in adult community education programs have not been adequately addressed. Furthermore, the research suggests that a number of variables, such as, native language, age, prior schooling, length of residence, and employment are related to second language acquisition. Numerous studies contribute to our understanding of the relationship of these factors to second language acquisition of Spanish-speaking students. Again, there is a void in the research investigating the factors affecting second language acquisition and consequently, appropriate placement of Haitian Creole-speaking students. This study compared a standardized instrument, the NYS Place Test, used alone and in combination with a writing sample in English, to subjective judgement of a department coordinator for initial placement of Haitian adult ESOL students in a community education program. The study also investigated whether or not consideration of student profile data improved the accuracy of the test. Finally, the study sought to determine if a relationship existed between student profile data and those who withdrew from the program or did not enter a class after registering. Analysis of the data by crosstabulation and chi-square revealed that the standardized NYS Place Test was at least as accurate as subjective department coordinator placement and that one procedure could be substituted for li other. Although the writing sample in English improved accuracy of placement by the NYS test, the results were not significant. Of the profile variables, only length of residence was found to be significantly related to accuracy of placement using the NYS Place Test. The number of incorrect placements was higher for those students who lived in the host country from twenty-five to one hundred ten months. A post hoc analysis of NYS test scores according to level showed that those learners who placed in level three also had a significantly higher incidence of incorrect placements. No significant relationship was observed between the profile variables and those who withdrew from the program or registered but did not enter a class.

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The individual effects that echoic, mand, and sign language training procedures have on the acquisition of verbal behavior have been widely demonstrated, but more efficient strategies are still needed. This study combined all three treatment strategies into one treatment intervention in order to investigate the joint effects they may have on verbal behavior. Six participants took part in the study. Intervention totaled 1 hour/day for 5 days/week until mastery criterion for motor echoic behavior was achieved. Although motor echoic behavior were solely targeted for acquisition, significant increases in spontaneous motor mands were noted in all treatment participants. Additionally, 4 treatment participants also demonstrated significant gains in vocal echoics and spontaneous vocal mands. No significant increases were noted for the control participant. Results suggest that the aforementioned procedure may provide more efficient results as a first-step to teaching a functional repertoire of verbal behavior to developmentally delayed children.

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This research aimed to describe, understand, and discuss the curriculum development process of a Brazilian-Portuguese heritage language community-based school in South Florida. This study was guided by the following research questions: (a) What roles does this HL community-based school aim to play for its students? This investigation was also related to the subsidiary question: (b) How does this HL community-based school organize its curriculum development process? In order to explore these research questions, I observed and interviewed teachers and coordinators based on a qualitative research approach. I analyzed the interviews’ transcripts, and the program’s website with a central focus of describing and understanding their curriculum development process. Hopefully, the findings will help Brazilian and other HL community schools toward discussing and elaborating their own curriculum development, as well as to look for specific teacher training courses.