Benchmark Framework for Virtual Students’ Behaviours

This paper demonstrates the integration and evaluation of different atmosphere models into Virtual Reality (VR) training for teacher education. We developed three behaviour models to simulate different levels of class discipline. We evaluated their performances using a combination of objective and subjective measurements. Our initial results suggest that the more believable and distinguishable classroom atmospheres are produced by creating more consistent behaviours across virtual students. Our results confirm the importance of similar behaviours to elicit a particular atmosphere

Determination of organ tropism of Newcastle disease virus (strain I-2) by virus isolation and reverse transcription-polymerase chain reaction

The vaccines 1-2 and V4 are avirulent strains of Newcastle disease virus. Organ tropism of strain V4 has been determined and the virus has a predilection for the digestive tract. Tropism of strain 1-2 has not yet been determined. The objective of this study was to determine the distribution of strain 1-2 in various body organs and fluids following vaccination in comparison with V4. Four-week-old chickens were vaccinated by eye drop separately with these two avirulent strains. Virus isolation and the reverse transcription-polymerase chain reaction technique were employed to detect 1-2 and V4 viruses in various tissues and body fluids for 7 days following vaccination. Tissues from the respiratory tract showed earlier positive signals than tissues from other organs for chickens vaccinated with strain 1-2. Conversely, tissues from mainly digestive tract produced earlier positive signals than from respiratory tract and other organs from chickens vaccinated with strain V4. In early infection, strain 1-2 had preferential predilection for the respiratory tract and strain V4 for the digestive tract. Later after vaccination, other organs showed positive results from chickens vaccinated with both 1-2 and V4 strains. The differences in organ tropism observed in this study suggest that 1-2 may perform better than V4 as a live vaccine strain

Newcastle disease virus fusion and haemagglutinin-neuraminidase gene motifs as markers for viral lineage

Reverse transcriptase polymerase chain reaction was used to generate sequence data for 91 Australian Newcastle disease viruses (NDV) isolated from 1932 to 2000 covering the cleavage site of the fusion (F) protein and the C-terminus of the haemagglutinin-neuraminidase (HN) protein. Comparison of sequences at these two sites indicates distinct evolutionary relationships between these viruses. Typically, HN gene relationships revealed by phylogenetic analyses were also maintained in comparisons between F gene cleavage sites; however, the former analyses appeared to give a clearer indication of the lineage of a virus isolate. This data supports and extends earlier observations in that there is no evidence for gene exchange by recombination but that different strains appear to have evolved through synonymous mutations. Inter-relationships, especially between Australian NDV isolates, appear to be associated with lineages having the same C-terminal HN extensions rather than associated with virulence of the virus. A proposed mechanism for this observation is discussed

Genetic models reveal origin, persistence and non-redundant functions of IL-17-producing γδ T cells.

γδ T cells are highly conserved in jawed vertebrates, suggesting an essential role in the immune system. However, γδ T cell-deficient Tcrd-/- mice display surprisingly mild phenotypes. We hypothesized that the lack of γδ T cells in constitutive Tcrd-/- mice is functionally compensated by other lymphocytes taking over genuine γδ T cell functions. To test this, we generated a knock-in model for diphtheria toxin-mediated conditional γδ T cell depletion. In contrast to IFN-γ-producing γδ T cells, IL-17-producing γδ T cells (Tγδ17 cells) recovered inefficiently after depletion, and their niches were filled by expanding Th17 cells and ILC3s. Complementary genetic fate mapping further demonstrated that Tγδ17 cells are long-lived and persisting lymphocytes. Investigating the function of γδ T cells, conditional depletion but not constitutive deficiency protected from imiquimod-induced psoriasis. Together, we clarify that fetal thymus-derived Tγδ17 cells are nonredundant local effector cells in IL-17-driven skin pathology

Development of Interleukin-17-Producing γδ T Cells Is Restricted to a Functional Embryonic Wave.

γδ T cells are an important innate source of interleukin-17 (IL-17). In contrast to T helper 17 (Th17) cell differentiation, which occurs in the periphery, IL-17-producing γδ T cells (γδT17 cells) are probably committed during thymic development. To study when γδT17 cells arise during ontogeny, we used TcrdH2BeGFP reporter mice to monitor T cell receptor (TCR) rearrangement and IL-17 production in the embryonic thymus. We observed that several populations such as innate lymphoid cells and early T cell precursors were able to produce IL-17 prior to (and thus independent of) TCR recombination. γδT17 cells were absent after transplantation of IL-17-sufficient bone marrow into mice lacking both Il17a and Il17f. Also, γδT17 cells were not generated after genetic restoration of defective Rag1 function in adult mice. Together, these data suggested that these cells developed exclusively before birth and subsequently persisted in adult mice as self-renewing, long-lived cells