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No description available.

No description available.

No description available.

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This research examined the relationships between the Big Five human personality traits, favorable social conditions, and foreign language classroom speaking confidence. Four research questions were investigated concerning the validity of the Big Five for a Japanese university sample, the composition of Foreign Language Classroom Speaking Confidence, the degree to which the Big Five influenced Foreign Language Classroom Speaking Confidence, and the degree to which perceptions of classroom climate affect Foreign Language Classroom Speaking Confidence. The first stage of the research involved three pilot studies that led to the revision of the Big Five Factor Marker questionnaire and the creation of a new instrument for measuring foreign language classroom speaking confidence that included both cognitive and social factors as theorized in mainstream social anxiety research. The second stage of the research involved the collection and analysis of data from 1,081 participants studying English in 12 universities throughout Japan. Data were analyzed using a triangulation of Rasch analysis, exploratory factor analysis (EFA), and confirmatory factor analysis (CFA) in order to verify the construct validity of the eleven hypothesized constructs. Following validation of the measurement model, the latent variables were placed into a structural regression model, which was tested by using half of the data set as a calibration sample and confirmed by using the second half of the data set as a validation sample. The results of the study indicated the following: (a) four of the five hypothesized Big Five personality traits were valid for the Japanese sample; (b) Foreign Language Classroom Speaking Confidence comprised three measurement variables, Foreign Language Classroom Speaking Anxiety, Perceived Foreign Language Speaking Self-Competence, and Desire to Speak English; (c) Emotional Stability and Imagination directly influenced Foreign Language Classroom Speaking Confidence, and; (d) Current English Classroom Perception and Perceived Social Value of Speaking English directly influenced Foreign Language Classroom Speaking Confidence. The findings thus demonstrated a link between personality, positive classroom atmosphere, and foreign language classroom speaking confidence. The implications of the findings included the possibility that foreign language anxiety is not situation-specific as theorized, and that improved social relations within the foreign language classroom might help reduce speaking anxiety. / CITE/Language Arts

Since late 1980s, porcine reproductive and respiratory syndrome virus (PRRSV) has emerged as the most economically important swine pathogen affecting pig industries worldwide. Vaccination is the principal means that have been used for prevention of PRRSV infection. However, the currently available vaccines for PRRSV are generally considered as not very effective. One of the major obstacles for developing an effective modified live-attenuated vaccine (MLV) with broad protection is the delayed and insufficient immune responses mounted by PRRSV, and the problem is further exacerbated by the antigenic variations of the constantly-evolving field strains of PRRSV. In order to boost the immune response induced by the MLV vaccine virus, we evaluated the immunogenicity and vaccine efficacy of recombinant PRRSV MLVs expressing porcine IL-15 or IL-18 as adjuvants. The cytokine genes were fused with a GPI modification signal so that they are anchored onto the cell surface upon infection with the recombinant MLV. Both cytokines are successfully expressed on the cell membrane of porcine alveolar macrophage (PAMs) after recombinant MLVs infection in vitro. Subsequently, pigs vaccinated with cytokine-expressing recombinant PRRSV MLVs had an improved antiviral response of cytotoxic lymphocytes including natural killer (NK) cells and T cells, characterized by increased IFN-γ secretion and/or enhanced CD107a expression. The results offer a novel strategy to incorporate cytokine genes into PRRSV genome as potent bio-active adjuvants expressed by the vaccine virus itself. Since we showed that PRRSV VR2385 down-regulated swine leukocyte antigen class I surface expression, naturally the next logical question is which viral protein is responsible for this down-regulation. To answer the question, we cloned and expressed all known PRRSV structural and non-structural proteins and examined which protein(s) is involved in SLA-I downregulation. Our results identified the newly-discovered nonstructural protein Nsp2TF of PRRSV as the main mediator in down-regulating SLA-I expression. We also demonstrated that the Nsp2TF-knockout mutant virus lost its function of negatively modulating SLA-I presentation compared to the wild-type virus. The results suggest that disruption of the Nsp2TF's ability to down-regulate SLA-I expression may improve the existing PRRSV vaccines towards a better CMI response against the virus. / PHD / Porcine reproductive and respiratory syndrome virus (PRRSV) is an important swine pathogen, causing enormous economical losses in the pork industry worldwide. However, the vaccine program is not satisfactory, with the insufficient protection against genetically divergent strains and newly emerged strains. One of the most important reasons is that PRRSV is able to suppress immune responses in the host, but the underlying mechanisms are not well known. Therefore, the first dissertation study is to investigate novel strategies of developing live-attenuated vaccines with improved efficacy against PRRSV. In this study, we successfully generated recombinant PRRSV live vaccines that are able to express immuno-activating cytokines as adjuvants. Subsequently, pigs vaccinated with cytokine-expressing PRRSVs had significantly improved anti-PRRSV immune repsonses when compared to pigs vaccinated with unmodified PRRSV. Those recombinant PRRSVs also provided cross-protection against a heterologous PRRSV challenge. The second part of disseration research is to understand the mechanism of immune modulation by PRRSV. Our results showed that one of PRRSV proteins- Nsp2TF contributes to the PRSV-induced down-regulation of swine leukocyte antigen (SLA) class I expression. Since SLA class I molecules are essential in the activation of the immune response and required for the clearance of viruses, Our study suggested that knocking-out Nsp2TF could be of great value to generate PRRSV vaccines with a better immune response.

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Proper spelling is important for efficient communication between people with different first languages in the 21st century. While Swedish functions as an intranational language within Sweden, it sees little to no use outside of Scandinavia. English fills the role as a second language that all Swedish students must learn, yet more focus appears to be given to grammar rather than spelling. Spelling is important and knowing the kinds of spelling errors Swedish learners of English tend to make can help educators improve the spelling proficiency of their students. The aim of this study is to investigate the spelling errors made by senior high school students in Sweden by analyzing a collection of essays written by students and gathered in the Uppsala Learner English Corpus (ULEC). The results of this study show that spelling proficiency nearly doubled for students in their third year in senior high school compared to their first year, yet the distribution of spelling errors remained the same. Additionally, some particular sounds that appear to be especially problematic for Swedish spellers were identified, such as /ə/, /l/, /s/ and /k/. / Korrekt stavning är viktig för effektiv kommunikation mellan människor med olika modersmål i tjugohundratalet. Medans svenska fungerar som ett språk mellan människor inom Sverige, ser det lite till ingen nytta utanför Skandinavien. Engelska fyller rollen som andraspråk som alla svenska elever måste lära sig, ändå sätts mer fokus på grammatik över stavning. Stavning är viktig och att veta vilka typer av stavfel som svenska elever brukar göra på engelska kan hjälpa lärare förbättra elevernas stavningskunskaper. Syftet med den här studien är att undersöka svenska gymnasielevers felstavningar i Engelska genom att analysera en samlig essäer skrivna av studenter och samlade i Uppsala Learner English Corpus (ULEC). Resultaten från den här studien visar att stavningskunskaperna hos eleverna hade nästan fördubblats när de gick det tredje år på gymnasiet jämfört med när de gick det första, men att fördelningen av stavfel förblev densamma. Dessutom har vissa ljud identifierats som verkar vara särskilt problematiska för svenska elever att stava, såsom /ə/, /l/, /s/ and /k/.