John Stephens results 926
· Newest (Page 1/38, per page 25)
Author: John Stephens ×Clear All Filters
Search Results
Since 2020, recurrent mortalities have been reported in grow-out farms in the Ruvu River basin in Tanzania’s Pwani region. This study investigated bacterial pathogens associated with these outbreaks. A cross-sectional survey was conducted between March 2022 and November 2023 in four affected tilapia farms. A total of 60 moribund fish were sampled. Clinical examination revealed skin ulcers, hemorrhages, fin erosion, abdominal d...
Marek’s disease (MD) is caused by the highly contagious Marek’s disease virus (MDV), a tumorigenic alphaherpesvirus. The disease is presently managed through vaccination. Nevertheless, the dynamic nature of MDV presents challenges, as new virulent strains may arise that can potentially overcome existing vaccine-mediated immunity. To address this, new and more effective vaccines are crucial. The immune system’s first line of de...
Assessing Climate Adaptation Among Canada Lynx ( Lynx canadensis ) Populations at the Trailing EdgeNARA Subscribed
Species must acclimate, shift their distribution, or adapt in place in response to anthropogenic climate change. Populations at the low‐latitude trailing edge of the species distribution typically experience thermal conditions closest to the upper limit of their thermoregulatory capacity. Landscape and functional genomic approaches provide quantitative measures of risk and adaptive capacity which can inform and prioritise cons...
A captive‐reared cohort of Laurel Dace, Chrosomus saylori (Skelton 2001) (Cypriniformes: Leuciscidae), a federally‐endangered species endemic to several streams in eastern Tennessee's Cumberland Plateau, exhibited signs of morbidity and trickling mortalities in a recirculating aquaculture system. Ziehl‐Neelsen (ZN) staining revealed acid‐fast rod‐shaped bacteria within necrotic and intracellular lesions affecting the eye, swim...
Antibiotics cause significant gut microbiome dysbiosis, particularly when administered orally. This contributes to antimicrobial resistance (AMR) and is associated with myriad health conditions. Novel drug delivery strategies that minimize gut exposure while maintaining therapeutic efficacy are urgently needed. This study aimed to evaluate whether a novel transdermal system could reduce gut microbiome disruption compared to or...
Exposure to chemical pollutants can alter the rate and genome‐wide distribution of germline mutations. However, studies measuring the effects of chemical exposure on mutation rates and spectra have not considered the ecological and evolutionary backgrounds of the studied genotypes, which could influence the rates and patterns of germline mutations in altered environments, for example, chemical pollution. Utilising a study of n...
Interpretable deep learning reveals spatiotemporal MRI features of brain aging that align with neurodegenerationNARA Subscribed
Cortical thinning and atrophy are hallmarks of brain aging that have been characterized using magnetic resonance imaging (MRI). Brain aging involves many neuroanatomic features whose effects on brain structure remain unexplored. To address this challenge, we trained interpretable deep neural networks (DNNs) to estimate brain age (BA) from T 1 -weighted ( T 1 w) MRI. By identifying MRI features unapparent to humans, DNNs can fi...