Long-term satellite record reveals likely recent aerosol trend

Analysis of the long-term Global Aerosol Climatology Project data set reveals a likely decrease of the global optical thickness of tropospheric aerosols by as much as 0.03 during the period from 1991 to 2005. This recent trend mirrors the concurrent global increase in solar radiation fluxes at Earth's surface and may have contributed to recent changes in surface climate.     

DNA Vaccination Partially Protects Muskellunge against Viral Hemorrhagic Septicemia Virus (VHSV-IVb)

Abstract

A DNA vaccine containing the glycoprotein (G) gene of the North American viral hemorrhagic septicemia virus (VHSV) genotype IVb was developed to evaluate the immune response of fish following vaccination and evaluate its efficacy in protecting a susceptible species, the Muskellunge Esox masquinongy, against VHSV-IVb challenge. Seven weeks (539 degree-days) following vaccination with 10 μg of either pVHSivb-G or a control plasmid, Muskellunge were challenged by immersion with 10⁵ plaque-forming units (pfu)/mL of VHSV-IVb. Fish vaccinated with pVHSivb-G had a relative percent survival (RPS) of 45%. Vaccinated fish also had significantly lower mean viral titers in tissues (4.2 × 10² pfu/g) and viral prevalence (4%) than fish receiving the plasmid control vaccine (3.3 × 10⁵ pfu/g; 82%). Neutralizing antibodies were detected 28 d (308 degree-days) postchallenge (11 weeks postvaccination) in 100% of Muskellunge vaccinated with pVHSivb-G compared with only 12% of plasmid-control-vaccinated Muskellunge, suggesting robust induction of a secondary, adaptive immune response. In addition, pVHSivb-G–vaccinated Rainbow Trout Oncorhynchus mykiss challenged 7 d (100 degree-days) postvaccination with the heterologous novirhabdovirus, infectious hematopoietic necrosis virus (IHNV), experienced an RPS of 61%, compared to control fish, suggesting induction of an early and transient nonspecific antiviral immune response. This study provides an important starting point for VHSV-IVb vaccine development and useful information about the antiviral immune response elicited by DNA vaccination in a nondomesticated fish species.

Received May 1, 2016; accepted September 1, 2016     

Genetic regulation of conidiation in Trichoderma hamatun

Achieving a balance between vegetative growth and spore production is essential for successful biocontrol by fungi. Low sporulation rates in the field can result in poor establishment and survival,whereas failure of conidia to recognise hosts can lead to persistence without efficacy. Commercial biocontrol products involve bulk preparations of conidia, however considerable variability in conidiation rates exists between biocontrol agents, which can restrict choice of strain for production. The majority of studies on Trichoderma conidiation have focused on the species T. viride and T. atroviride.These species form conidia in response to blue and near-UV light and/or nutrient deprivation and conidiation proceeds in a highly co-ordinated fashion, however relatively little is known on the genetic basis of Trichoderrma conidiation. In addition, whilst photoconidiation appears to be a general response detailed studies in other Trichoderma species are absent. In this study, conidiation in the lesser known biocontrol species T. hamatum is being investigated using a combined morphological and molecular approach. In contrast to T. atroviride, conidiation in response to blue-light was weaker and variable and suggested that additional triggers may be required for the T. hamatum photoresponse. A series of comparative photoconidiation assays are currently being undertaken investigating the effect of inoculum type and abiotic factors on timing and intensity of the response.Results will be discussed in relation to the current knowledge on conidial morphogenesis in Trichoderma. In addition to these morphological assays, a selection of genes implicated in sporulation and the blue-light responses are currently being isolated and characterised from T. hamatum. Two genes, phr1 and cmp1 , which were isolated previously from T. atroviride will be used as early and late markers of gene expression during the photoresponse in T. hamatum in order to define time points for harvesting comparable stage-specific RNA from T. hamatum and T. atroviride. Using degenerate PCR putative sporulation gene orthologues have also been identified in T. hamatum.Work is currently underway to isolate genomic clones of these genes from T. hamatum and T.atroviride. Sequence and expression analysis of orthologues, including expression in response to abiotic factors will be presented and discussed in relation to the current knowledge of the molecular basis of conidiation in Trichoderma and other filamentous fungi.……     

A short review of transmissible spongiform encephalopathies, and guidelines for managing risks associated with chronic wasting disease in captive cervids in zoos.

The transmissible spongiform encephalopathies (TSEs) represent an emerging group of diseases that have been labeled as "prion diseases" because of the recent characterization of the infectious agent. TSEs are caused by prions, which induce neurodegenerative fatal diseases in humans and animals. Some TSEs (scrapie and kuru), have existed in both animals and humans for a very long time, whereas others such as bovine spongiform encephalopathy and variant Creutzfeld-Jakob disease have either recently emerged or are more thoroughly described and recognized. It is obvious that the medical community will be forced to consider these diseases in humans and animals for the future. This article offers a short review of the TSEs of immediate concern to zoo and wildlife veterinarians and wildlife biologists and suggests risk management strategies for the prevention of these diseases, with special focus on chronic wasting disease of cervids in North America.     

Getting lost in the matrix? On how the characteristics and arrangement of linear landscape elements influence ecological connectivity

Landscape Ecology - Linear landscape elements (LLEs) such as ditches and hedgerows can increase the ecological connectivity of habitat embedded within agricultural areas by acting as corridors for...