Over the last three decades, the causative agent of viral encephalopathy and retinopathy (VER) disease has become a serious problem of marine finfish aquaculture, and more recently the disease has ...also been associated with farmed freshwater fish. The virus has been classified as a Betanodavirus within the family Nodaviridae, and the fact that Betanodaviruses are known to affect more than 120 different farmed and wild fish and invertebrate species, highlights the risk that Betanodaviruses pose to global aquaculture production.
Betanodaviruses have been clustered into four genotypes, based on the RNA sequence of the T4 variable region of their capsid protein, and are named after the fish species from which they were first derived i.e. Striped Jack nervous necrosis virus (SJNNV), Tiger puffer nervous necrosis virus (TPNNV), Barfin flounder nervous necrosis virus (BFNNV) and Red-spotted grouper nervous necrosis virus (RGNNV), while an additional genotype turbot betanodavirus strain (TNV) has also been proposed. However, these genotypes tend to be associated with a particular water temperature range rather than being species-specific.
Larvae and juvenile fish are especially susceptible to VER, with up to 100% mortality resulting in these age groups during disease episodes, with vertical transmission of the virus increasing the disease problem in smaller fish. A number of vaccine preparations have been tested in the laboratory and in the field e.g. inactivated virus, recombinant proteins, virus-like particles and DNA based vaccines, and their efficacy, based on relative percentage survival, has ranged from medium to high levels of protection to little or no protection.
Ultimately a combination of effective prophylactic measures, including vaccination, is needed to control VER, and should also target larvae and broodstock stages of production to help the industry deal with the problem of vertical transmission. As yet there are no commercial vaccines for VER and the aquaculture industry eagerly awaits such a product. In this review we provide an overview on the current state of knowledge of the disease, the pathogen, and interactions between betanodavirus and its host, to provide a greater understanding of the multiple factors involved in the disease process. Such knowledge is needed to develop effective methods for controlling VER in the field, to protect the various aquaculture species farmed globally from the different Betanodavirus genotypes to which they are susceptible.
•Current knowledge of disease, pathogen and interactions between virus and host.•Understanding transmission of the virus and host susceptibility.•Insight into the multiple factors involved in Betanodavirus disease process.•Prophylactic measures for VER reviewed including vaccine development.
There is a growing interest by governments and academics in including Indigenous knowledge alongside scientific knowledge in environmental management, including monitoring. Given this growing ...interest, a critical review of how Indigenous peoples have been engaged in monitoring is needed. We reviewed and analyzed the academic literature to answer the following questions: How have Indigenous peoples participated in environmental monitoring, and how has their participation influenced monitoring objectives, indicators, methods, and monitoring outcomes? We also summarized how this literature discussed power, governance, and the use of both Indigenous and scientific knowledge in environmental monitoring efforts. We found that the literature most often characterized participation as data collection, and that higher degrees of participation and power held by Indigenous peoples in environmental monitoring leads to initiatives that have different objectives, indicators, and outcomes than those with heavier involvement of external groups. Our review also showed that a key challenge of conducting effective monitoring that leverages both Indigenous knowledge systems and science is the power imbalances that uncouple Indigenous monitoring efforts from management. We encourage future initiatives to carefully consider the ways in which power and governance shape their programs and the ability of their monitoring to lead to meaningful management actions.
An individual is typically considered an adult at age 18, although the age of adulthood varies for different legal and social policies. A key question is how cognitive capacities relevant to these ...policies change with development. The current study used an emotional go/no-go paradigm and functional neuroimaging to assess cognitive control under sustained states of negative and positive arousal in a community sample of one hundred ten 13- to 25-year-olds from New York City and Los Angeles. The results showed diminished cognitive performance under brief and prolonged negative emotional arousal in 18- to 21-year-olds relative to adults over 21. This reduction in performance was paralleled by decreased activity in fronto-parietal circuitry, implicated in cognitive control, and increased sustained activity in the ventromedial prefrontal cortex, involved in emotional processes. The findings suggest a developmental shift in cognitive capacity in emotional situations that coincides with dynamic changes in prefrontal circuitry. These findings may inform age-related social policies.
The jawless vertebrates (agnathans/cyclostomes) are ancestral animals comprising lampreys and hagfishes as the only extant representatives. They possess an alternative adaptive immune system (AIS) ...that uses leucine-rich repeats (LRR)-based variable lymphocyte receptors (VLRs) instead of the immunoglobulin (Ig)-based antigen receptors of jawed vertebrates (gnathostomes). The different VLR types are expressed on agnathan lymphocytes and functionally resemble gnathostome antigen receptors. In particular, VLRB is functionally similar to the B cell receptor and is expressed and secreted by B-like lymphocytes as VLRB antibodies that bind antigens with high affinity and specificity. The potential repertoire scale of VLR-based antigen receptors is believed to be at least comparable to that of Ig-based systems. VLR proteins inherently possess characteristics that render them excellent candidates for biotechnological development, including tractability to recombinant approaches. In recent years, scientists have explored the biotechnological development and utility of VLRB proteins as alternatives to conventional mammalian antibodies. The VLRB antibody platform represents a non-traditional approach to generating a highly diverse repertoire of unique antibodies. In this review, we first describe some aspects of the biology of the AIS of the jawless vertebrates, which recognizes antigens by means of unique receptors. We then summarize reports on the development of VLRB-based antibodies and their applications, particularly those from the inshore hagfish (Eptatretus burgeri) and their potential uses to address microbial diseases in aquaculture. Hagfish VLRB antibodies (we call Ccombodies) are being developed and improved, while obstacles to the advancement of the VLRB platform are being addressed to utilize VLRBs effectively as tools in immunology. VLRB antibodies for novel antigen targets are expected to emerge to provide new opportunities to tackle various scientific questions. We anticipate a greater interest in the agnathan AIS in general and particularly in the hagfish AIS for greater elucidation of the evolution of adaptive immunity and its applications to address microbial pathogens in farmed aquatic animals and beyond.
•The agnathan adaptive immune system uses leucine-rich repeats-based variable lymphocyte receptors (VLRs) to recognize antigens.•VLRB proteins secreted by B-like cells are analogous to gnathostome antibodies.•VLRB proteins have been developed as alternatives to immunoglobulin antibodies.•VLRB antibodies from the hagfish Eptatretus burgeri have been developed as immunological tools in aquaculture.•Difficulties need to be tackled to effectively develop and utilize VLRB antibodies as immunological reagents.
Butter clams, blue mussels, and Nuttall's cockle are important traditional food of the Gitga'at First Nation in Canada. Samples were collected and analyzed for polycyclic aromatic hydrocarbon (PAH) ...from the Gitga'at harvest sites from 2006 to 2015 to: 1) establish baseline conditions; 2) determine the likely source; 3) understand species specific response to spills; and 4) evaluate health risk associated with consumption. Baseline lipid normalized-total PAH in mussels was 2.36 (±2.86, 95%CI) μg/g in mussels, 3.26(±4.14) μg/g in clams and 3.98 (±4.98) μg/g in cockles. PAHs varied according to proximity to point sources and became less petrogenic through time. Concentrations of PAHs were elevated in all three species following diesel spills but returned to baseline levels within 5months. However, Gitga'at harvesters avoided bivalves from spill-affected habitats for several years because of their detection of reduced quality and palatability, highlighting the importance of incorporating local knowledge into future monitoring programs.
•Baseline PAH concentrations in bivalves from Gitga'at Territory were reported.•PAHs were elevated following diesel spills but returned to baseline within 5months.•Human health risk of consumption was low.•Gitga'at harvesters avoided bivalves from spill-affected habitats for several years.•Incorporating local knowledge into future monitoring programs is important.
Gram-negative bacteria have an outer membrane inhibiting the entry of antibiotics. Porins, found within the outer membrane, are involved in regulating the permeability of β-lactam antibiotics. ...β-lactamases are enzymes that are able to inactivate the antibacterial properties of β-lactam antibiotics. Interestingly, porins and β-lactamase are found in outer membrane vesicles (OMVs) of β-lactam-resistant
and may be involved in the survival of susceptible strains of
in the presence of antibiotics, through the hydrolysis of the β-lactam antibiotic. In this study, OMVs isolated from β-lactam-resistant
and from mutants, lacking porin or β-lactamase, were evaluated to establish if the porins or β-lactamase in OMVs were involved in the degradation of β-lactam antibiotics. OMVs isolated from
deficient in β-lactamase did not show any degradation ability against β-lactam antibiotics, while OMVs lacking OmpC or OmpF showed significantly lower levels of hydrolyzing activity than OMVs from parent
. These data reveal an important role of OMVs in bacterial defense mechanisms demonstrating that the OmpC and OmpF proteins allow permeation of β-lactam antibiotics into the lumen of OMVs, and antibiotics that enter the OMVs can be degraded by β-lactamase.
Purpose - The purpose of the research reported in this article is to understand how refugees learn to engage with a complex, multimodal information landscape and how their information literacy ...practice may be constructed to enable them to connect and be included in their new information landscape. Design methodology approach - The study is framed through practice and socio-cultural theories. A qualitative research design is employed including semi-structured face-to-face interviews and focus groups which are thematically analysed through an information practice lens. Findings - Refugees encounter complex and challenging information landscapes that present barriers to their full participation in their new communities. Social inclusion becomes possible where information is provided via sharing through trusted mediators who assist with navigating the information landscape and information mapping, and through visual and social sources. Research limitations implications - The study is local and situated and therefore not empirically generalizable. It does however provide rich, deep description and explanation that is instructive beyond the specific research site and contributes to theory building. Practical implications - The study highlights the role, and importance, of social and visual information sources and the key role of service providers as mediators and navigators. Governments, funders and service providers can use these findings to inform their service provision. Originality value - This is an original research paper in which the results provide practical advice for those working with refugees and which also extends theories of information literacy practice as an information practice.
Fin whales (Balaenoptera physalus) are widely considered an offshore and oceanic species, but certain populations also use coastal areas and semi-enclosed seas. Based upon fifteen years of study, we ...report that Canadian Pacific fin whales (B. p. velifera) have returned to the Kitimat Fjord System (KFS) in the Great Bear Rainforest, and have established a seasonally resident population in its intracoastal waters. This is the only fjord system along this coast or elsewhere in which fin whales are known to occur regularly with strong site fidelity. The KFS was also the only Canadian Pacific fjord system in which fin whales were commonly found and killed during commercial whaling, pointing to its long-term importance. Traditional knowledge, whaling records, and citizen science databases suggest that fin whales were extirpated from this area prior to their return in 2005-2006. Visual surveys and mark-recapture analysis documented their repopulation of the area, with 100-120 whales using the fjord system in recent years, as well as the establishment of a seasonally resident population with annual return rates higher than 70%. Line transect surveys identified the central and outer channels of the KFS as the primary fin whale habitat, with the greatest densities occurring in Squally Channel and Caamaño Sound. Fin whales were observed in the KFS in most months of the year. Vessel- and shore-based surveys (27,311 km and 6,572 hours of effort, respectively) indicated regular fin whale presence (2,542 detections), including mother-calf pairs, from June to October and peak abundance in late August-early September. Seasonal patterns were variable year-to-year, and several lines of evidence indicated that fin whales arrived and departed from the KFS repeatedly throughout the summer and fall. Additionally, we report on the population's social network and morphometrics. These findings offer insights into the dynamics of population recovery in an area where several marine shipping projects are proposed. The fin whales of the Great Bear Rainforest represent a rare exception to general patterns in this species' natural history, and we highlight the importance of their conservation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Emergencies can create situations where traditional face-to-face courses need to quickly be transferred to be online. When transitioning, it is easy to focus on simply moving content into an online ...learning management system quickly and training instructors and students in the basics of how to use the platform in a pared-down learning structure. However, this article argues that approaching emergency course redesign with accessibility in mind at the start of the transition will ensure that more students, including students with disabilities, succeed in the online learning environment. This also helps ensure the course is designed for optimal student learning outcomes.
The presence of CD4 T lymphocytes has been described for several teleost species, while many of the main T cell subsets have not been characterized at a cellular level, because of a lack of suitable ...tools for their identification, e.g., monoclonal antibodies (mAbs) against cell markers. We previously described the tissue distribution and immune response related to CD3ε and CD4-1 T cells in olive flounder (
) in response to a viral infection. In the present study, we successfully produce an mAb against CD4-2 T lymphocytes from olive flounder and confirmed its specificity using immuno-blotting, immunofluorescence staining, flow cytometry analysis and reverse transcription polymerase chain reaction (RT-PCR). Using these mAbs, we were able to demonstrate that the CD3ε T cell populations contain both types of CD4
cells, with the majority of the CD4 T cell subpopulations being CD4-1
/CD4-2
cells, determined using two-color flow cytometry analysis. We also examined the functional activity of the CD4-1 and CD4-2 cells in vivo in response to a viral infection, with the numbers of both types of CD4 T cells increasing significantly during the virus infection. Collectively, these findings suggest that the CD4 T lymphocytes in olive flounder are equivalent to the helper T cells in mammals in terms of their properties and function, and it is the CD4-2 T lymphocytes rather than the CD4-1 T cells that play an important role in the Th1 immune response against viral infections in olive flounder.
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