Development and growth of hatchery-reared larval Florida pompano (Trachinotus carolinus)

Although the Florida pompano (Trachinotus carolinus) is a prime candidate for aquaculture, the problematic production of juveniles remains a major impediment to commercial culture of this species. In order to improve the understanding of larval development and to refine hatchery production techniques, this study was conducted to characterize development and growth of Florida pompano from hatching through metamorphosis by using digital photography and image analysis. Newly hatched larvae were transparent and had a large, elongate yolk sac and single oil globule. The lower and upper jaws as well as the digestive tract were not fully developed at hatching. Rotifers were observed in the stomach of larvae at three days after hatching (DAH), and Artemia spp. were observed in the stomach of larvae at 14 DAH. Growth rates calculated from total length measurements were 0.22 ±0.04, 0.23 ±0.12, and 0.35 ±0.09 mm/d for each of the larval rearing trials. The mouth gape of larvae was 0.266 ±0.075 mm at first feeding and increased with a growth rate of 0.13 ± 0.04 mm/d. Predicted values for optimal prey sizes ranged from 80 to 130 μm at 3 DAH, 160 to 267 μm at 5 DAH, and 454 to 757 μm at 10 DAH. Based on the findings of this study, a refined feeding regime was developed to provide stage- and size-specific guidelines for feeding Florida pompano larvae reared under hatchery co

Development of an Automated Template Selection and Alignment Tool for Protein Structure Homology Modeling

DNA and protein sequence data sets have exploded in size over the past several years and have stimulated the development of new methods for closing the sequence/structure gap. Bench laboratory methods, while being the most accurate, are still far too time consuming and limited to breech this gap. Thus computational methods have become the standard. The work described here details the development of a system to automatically select a structural template, align the template and query sequence and model the query. The system was implemented fully for antibodies but maintains a modular design that can accommodate a wider variety of molecule types. Extensive testing was performed using antibodies and the results of this analysis reveal the potential limitations of homology modeling and point toward ways to improve on the template selection method

Investigation of the roles of the actin cytoskeleton remodelling proteins coronin and CAP1 in platelet function

Platelets undergo profound rapid F-actin cytoskeleton remodeling and experience morphological and functional changes in response to receptor-mediated signaling from damaged blood vessel walls. The evolutionarily conserved proteins coronin 1 and adenylyl cyclase-associated protein 1 (CAP1) regulate the F-actin cytoskeleton and participate in signaling events. They are abundant in platelets but until recently their roles were poorly understood. Subcellular fractionation found coronin 1 is mainly cytosolic, but a significant amount associates with membranes in an actin- independent manner and does not translocate to or from the membrane upon platelet stimulation or inhibition. Coronin 1, 2 and 3 associate with the Triton insoluble cytoskeleton upon platelet stimulation. Immunostainings of spread platelets revealed that coronin 1, 2 and 3 demonstrate strong accumulation at F- actin nodules and display diffuse cytoplasmic localisation with discontinuous accumulation at the cell cortex. This is consistent with the role of coronins as integrators of extracellular signals with actin remodeling. Ablation of coronin 1 in platelets is associated with impaired translocation of integrin β2 to the cell surface upon stimulation with thrombin. However, morphological and functional defects are absent including Arp2/3 complex translocation, VASP phosphorylation, spreading ability, secretion, basal receptor levels, αIIbβ3 activation and haemostasis. While integrin β2 translocation appears specifically or predominantly dependent on coronin 1, the lack of other phenotypes suggests a high extent of functional overlap and redundancy among coronins 1, 2 and 3 in platelets. Subcellular fractionation found that ~20% of CAP1 is membrane-associated in an F-actin independent manner. Immunostainings demonstrated that in basal platelets CAP1 is mostly cortical whereas stimulation results in translocation to the cytosol in a significant proportion of platelets which can be inhibited by prostacyclin or nitric oxide. This places CAP1 at a crossroad of signalling pathways that controls platelet activation by contributing to actin remodelling at the cell cortex and actin nodules during platelet spreading

Cost and Benefit Analysis of Tomato Spotted Wilt Virus (TSWV) Management Technology in Georgia.

Recent trend depicts that tomatoes and tomatoes products rank 2nd most important vegetable crop in the United States after potatoes and potatoes products contributing 20 percent of total vegetable production. More-so, tomato is equally ranked 2nd in the United States in terms of production value, generating $1.3 billion after head lettuce that contributed$1.4 billion in the same time period. In 2006, 422,000 acres of tomatoes were planted in the United States. Tomato is equally an important economic crop in the state of Georgia. In 2008, it ranked 14th in the Georgia vegetable acreage as 3,985 acres were planted. It also ranked 6th in terms of farm gate value in the same time period generating $51.2 million. Thrips-vectored tomato spotted wilt virus (TSWV) is a serious disease capable of causing damages to the plant, fruits, quality and reducing yields drastically. Managing TSWV can be complex. For instance, metalized UV-mulch may significantly reduce TSWV, but delay tomato maturity, potentially affecting price and market window. Also, resistant tomato lines may eliminate damages due to TSWV, but could have negative horticultural attributes that standard TSWV-susceptible hybrids do not. TSWV can induce irregular ripening in fruit after packing, affecting post harvest costs. This study is aimed at providing the optimal return per unit of enterprise using cost and benefit estimates of the combination of available inputs used in the various management strategies. Thereafter, the result of the differentially developed techniques and risk-rated cost and benefit budgets will be used to determine which of the risk-rated thrips, TSWV and IPM decision criteria would provide superior pareto-optimal economic and financial benefit to tomato growersTomatoes production, Tomato Spotted Wilt Virus (TSWV), inputs, fixed cost, variable costs, profitability, cost and benefit., Agribusiness, Agricultural and Food Policy, Agricultural Finance, Crop Production/Industries, Environmental Economics and Policy, Farm Management, Financial Economics, Health Economics and Policy, Marketing, Production Economics, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies, Risk and Uncertainty, Teaching/Communication/Extension/Profession,

Differential IL-18 dependence of canonical and adaptive NK cells for antibody dependent responses to P. falciparum

Human adaptive natural killer (NK) cells have diminished reliance on accessory cytokines for their activation whilst being efficiently activated by infected host cells in conjunction with pathogen specific antibodies. Here, we show that potent antibody-dependent NK cell responses are induced by Plasmodium falciparum infected erythrocytes (iRBC) in peripheral blood mononuclear cells (PBMC) from malaria-exposed Gambian individuals in the presence of autologous sera, which are absent in those from malaria-naïve UK individuals. However, malaria hyper-immune serum promotes rapid NK cell responses to iRBC in cells from both Gambian and UK individuals. Among Gambians, highly differentiated, adaptive (CD56dimFcεR1γ-CD57+) NK cells dominate both antibody-dependent NK cell IFN-γ responses and degranulation responses, whereas among UK individuals these responses are predominantly found within canonical, highly differentiated CD56dimFcεR1γ+CD57+ NK cells. Indeed, overall frequencies of adaptive, FcεR1γ-CD57+ NK cells are significantly higher among Gambian donors compared to HCMV-infected and HCMV-uninfected UK adults. Among UK individuals, antibody-dependent NK cell IFN-γ responses to iRBC were dependent on IL-18 whereas among Gambians, the predominant adaptive FcεR1γ- NK cell response was IL-18 (and accessory cell) independent (although the lower frequency response of canonical FcεR1γ NK cells did rely on this cytokine)

Genomic analysis of clostridioides difficile recovered from horses in Western Australia

Clostridioides difficile poses an ongoing threat as a cause of gastrointestinal disease in humans and animals. Traditionally considered a human healthcare-related disease, increases in community-associated C. difficile infection (CDI) and growing evidence of inter-species transmission suggest a wider perspective is required for CDI control. In horses, C. difficile is a major cause of diarrhoea and life-threatening colitis. This study aimed to better understand the epidemiology of CDI in Australian horses and provide insights into the relationships between horse, human and environmental strains. A total of 752 faecal samples from 387 Western Australian horses were collected. C. difficile was isolated from 104 (30.9%) horses without gastrointestinal signs and 19 (37.8%) with gastrointestinal signs. Of these, 68 (55.3%) harboured one or more toxigenic strains, including C. difficile PCR ribotypes (RTs) 012 (n = 14), 014/020 (n = 10) and 087 (n = 7), all prominent in human infection. Whole-genome analysis of 45 strains identified a phylogenetic cluster of 10 closely related C. difficile RT 012 strains of equine, human and environmental origin (0–62 SNP differences; average 23), indicating recent shared ancestry. Evidence of possible clonal inter-species transmission or common-source exposure was identified for a subgroup of three horse and one human isolates, highlighting the need for a One Health approach to C. difficile surveillance

Salt Loading from Efflorescence and Suspended Sediments in the Price River Basin

Salinity control is a major component of water management in arid climates and irrigated areas and one of particular concern in the Colorado River Basin. The alts enter the water as it flows over land or moves through the soil or geologic formations. The principal salt collection processes are 1) dissolution from the soil surface during runoff events, 2) transpiration of soil water leaving salt residuals, 3) efflorescence left by evaporating seepage and then dissolved by subsequent runoff, 4) dissolution with weathering of fixed bed channels, 5) salts released by sediments entering the channel from sheet, gulley, and bank erosion, and 6) deep percolation through saline aquifer reaching the stream as base flow. This study examined processes 3 and 5. Salt efflorescence was examined by field observation and instrumentation, laboratory experiments, and mathematical modeling. The field data showed near saturation conditions of sodium sulfate waters below crusts of densities between 0.14 and 0.36 g/cm^2 and which formed over abouta 10-day period following channel cleaning by storm runoff. Laboratory data on salt crusting in soil columns were also used in developing a model which when applied to the Price River Basin estimated that no more than 7.5 percent of the total salt loading comes from salt efflorescence being carried away in the stream flow. The conditions favorable to the accumulation of salt efflorescence are highly saline water just below the soil surface and a source of heat for vaporizing the water. Salt release from suspended sediments was studied by laboratory experimentation with sediment material obtained from various locations in the Price River Basin. The Buckinham Pi Theorem was employed to derive relationships expressing the EC of a sediment water system as a function o fthe controlling factors. The results were presented in two salt release equations, one excluding the effect of initial EC and the other providing for initially saline solutions. The salt release equations were incorporated into an adapted version of the Watershed Erosion and Sediment Transport (WEST) model and applied to a small tributary of Coal Creek. Extrapolation to the entire Price River Basin led to an estimate that about 0.50 percent of the total annual salt load is released from suspened sediments. This study concludes that surface salt sources produce a relatvely small fraction of the total loading. Future studies need to go underground. They need to quantify and examine the flow lines of water movement from mountain source and valley floow recharge areas to points of emergence as base flow in the larger stream channels. They need to investigate the aquifers and their soluble salt content

Effects of different types of classroom physical activity breaks on children’s on-task behaviour, academic achievement and cognition

Aim This study examined the effects of different types of classroom physical activity breaks on children’s on-task behaviour, academic achievement and cognition. Methods Participants were 87 Australian primary school students (mean age 9.11 ± 0.62 years), recruited from one school. Three classes were randomly assigned either to activity breaks only (n = 29), activity breaks and mathematics combined (n = 29), or control conditions involving only mathematical content (n = 29). Students were engaged in five minutes of classroom physical activity breaks, three times per week, for four weeks (divided into two minutes at the beginning of the usual mathematics curriculum lesson and three minutes in the middle of the lesson). Assessments were conducted at baseline and post-test. Results Significant group-by-time effects were found for on-task behaviour (active engagement: activity breaks and mathematics combined versus control, p ≤ 0.001; activity breaks versus control, p ≤ 0.001; activity breaks and mathematics combined versus activity breaks, p = 0.037; passive engagement: activity breaks and mathematics combined versus control, p ≤ 0.001) and mathematics scores (activity breaks versus control, p = 0.045). Conclusion Physical activity breaks with and without integrated mathematics content were effective in improving children’s on-task behaviour and learning scores