Impact of Vaccination and Pathogen Exposure Dosage on Shedding Kinetics of Infectious Hematopoietic Necrosis Virus (IHNV) in Rainbow Trout

Vaccine efficacy in preventing clinical disease has been well characterized. However, vaccine impacts on transmission under diversefied conditions, such as variable pathogen exposure dosages, are not fully understood. We evaluated the impacts of vaccination on disease-induced host mortality and shedding of infectious hematopoietic necrosis virus (IHNV) in Rainbow Trout Oncorhynchus mykiss. Fish, in up to three different genetic lines, were exposed to different dosages of IHNV to simulate field variability. Mortality and viral shedding of each individual fish were quantified over the course of infection. As the exposure dosage increased, mortality, number offish shedding virus,daily virus quantity shed, and total amount of virus shed also increased. Vaccination significantly reduced mortality but had a much smaller impact on shedding, such that vaccinated fish still shed significant amounts of virus, particularly at higher viral exposure dosages. These studies demonstrate that the consideration of pathogen exposure dosage and transmission are critical for robust inference of vaccine efficacy

Proteomics of Buccal Cavity Mucus in Female Tilapia Fish (Oreochromis spp.): A Comparison between Parental and Non-Parental Fish

Mouthbrooding is an elaborate form of parental care displayed by many teleost species. While the direct benefits of mouthbrooding such as protection and transportation of offsprings are known, it is unclear if mouthbrooding offers additional benefits to embryos during incubation. In addition, mouthbrooding could incur negative costs on parental fish, due to limited feeding opportunities. Parental tilapia fish (Oreochromis spp.) display an elaborated form of parental care by incubating newly hatched embryos in oral buccal cavity until the complete adsorption of yolk sac. In order to understand the functional aspects of mouthbrooding, we undertake a proteomics approach to compare oral mucus sampled from mouthbrooders and non-mouthbrooders, respectively. Majority of the identified proteins have also been previously identified in other biological fluids or mucus-rich organs in different organisms. We also showed the upregulation of 22 proteins and down regulation of 3 proteins in mucus collected from mouthbrooders. Anterior gradient protein, hemoglobin beta-A chain and alpha-2 globin levels were lower in mouthbrooder samples. Mouthbrooder oral mucus collectively showed increase levels of proteins related to cytoskeletal properties, glycolytic pathway and mediation of oxidative stress. Overall the findings suggest cellular stress response, probably to support production of mucus during mouthbrooding phase

Influence of clays on fine particle filtration

Filtration of fine particle slurries is known to be inefficient in most plant operations and the problem is exacerbated by the presence of even small quantities of clay minerals. This paper discusses the influence of the commonly encountered clay types, bentonite and kaolin, in the filtration of a pyritic gold ore and how the adverse effects can be mitigated by the addition of Ca2+ ions and a hydrophobic reagent respectively, depending on the clay type. The presence of both kaolin and bentonite clays resulted in increasing specific cake resistance, filter medium resistance and final cake moisture content while effects of bentonite clay being more detrimental. The addition of hydrophobic reagent DAH (dodecylamine hydrochloride) improved the filtration rate of kaolincontaining ore. The moisture content of the filter cake was also reduced. By contrast, in the case of the bentonitecontaining ore, the presence of DAH did not affect the filtration rate and the moisture content. Filtration of the bentonite-containing ore was significantly improved with the addition of Ca2+ ions

Re-configurable supporting structures for aircraft industry

Aircraft industry is continuously seeking new technologies due to the competitive market and high demand. During maintenance and manufacturing practices, dedicated supporting structures are used to handle large parts of the aircraft. Manufacturing of a supporting structure is expensive and it requires longer lead time along with skilled work force. This research investigates the current methods used in supporting structures for aircraft assembly and maintenance purposes. Novel conceptual design models for different reconfigurable supporting structures are developed using 3D CAD software. The conceptual models are designed using standard parts which are readily available in the market. Each conceptual model is compared and contrasted according to their strengths and weaknesses. The most reliable conceptual models are identified by the easiness of assembling and disassembling in a shorter period of time. Furthermore, Finite Element Analysis (FEA) is used for further analyse the stress distribution, deformation and buckling tendency of proposed conceptual designs. Finally the safest and durable conceptual design is manufactured using widely available manufacturing processe