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Identification of new amoebae strains in rainbow trout ( Oncorhynchus mykiss , Walbaum) farms affected by nodular gill disease ( NGD ) in Northeastern Italy
No full textNodular gill disease (NGD) is an emerging condition associated with amoeba trophozoites in freshwater salmonid farms. However, unambiguous identification of the pathogens still must be achieved. This study aimed to identify the amoeba species involved in periodic NGD outbreaks in two rainbow trout (Oncorhynchus mykiss) farms in Northeastern Italy. During four episodes (February–April 2023), 88 fish were euthanized, and their gills were evaluated by macroscopic, microscopic and histopathological examination. The macroscopic and microscopic severity of the lesions and the degree of amoebae infestation were scored and statistically evaluated. One gill arch from each animal was put on non-nutrient agar (NNA) Petri dishes for amoeba isolation, cultivation and subsequent identification with SSU rDNA sequencing. Histopathology confirmed moderate to severe lesions consistent with NGD and mild to moderate amoeba infestation. The presence of amoebae was significantly correlated with lesion severity. Light microscopy of cultured amoebae strains and SSU rDNA analysis revealed the presence of a previously characterized amoeba Naegleria sp. strain GERK and several new strains: two strains from Hartmannelidae, three vannelid amoebae from the genus Ripella and cercozoan amoeba Rosculus. Despite the uncertainty in NGD etiopathogenesis and amoebae pathogenic role, identifying known and new amoebae leans towards a possible multi-aetiological origin.BCA DepartmentCzech Science Foundatio
The China firm: American elites and the making of British Colonial society
No full textWhat roles did Americans play in the expanding global empires of the nineteenth century? Thomas M. Larkin examines the Hong Kong–based Augustine Heard & Company, the most prominent American trading firm in treaty-port China, to explore the ways American elites at once made and were made by British colonial society. Following the Heard brothers throughout their firm’s rise and decline, The China Firm reveals how nineteenth-century China’s American elite adapted to colonial culture, helped entrench social and racial hierarchies, and exploited the British imperial project for their own profit as they became increasingly invested in its political affairs and commercial networks.
Through the central narrative of Augustine Heard & Co., Larkin disentangles the ties that bound the United States to China and the British Empire in the nineteenth century. Drawing on a vast range of archival material from Hong Kong, China, Boston, and London, he weaves the local and the global together to trace how Americans gained acceptance into and contributed to the making of colonial societies and world-spanning empires. Uncovering the transimperial lives of these American traders and the complex ways extraimperial communities interacted with British colonialism, The China Firm makes a vital contribution to global histories of nineteenth-century Asia and provides an alternative narrative of British empire
First report of Myxobolus neurofontinalis (Bivalvulida: Myxobolidae) infecting anadromous Brook Trout from Prince Edward Island, Canada
No full textObjective
During routine histological examination of tissues from mortality events of anadromous Brook Trout Salvelinus fontinalis from Prince Edward Island (PEI), Canada, myxospores consistent with Myxobolus were observed infecting the central nervous system. The objective of this study was to identify the species of Myxobolus infecting the nervous system of anadromous Brook Trout from PEI, Canada.
Methods
Myxospore morphology, small subunit (SSU) ribosomal DNA (rDNA) sequence data, and histology were used to identify myxospores isolated from infected Brook Trout.
Result
Myxospore measurements from the PEI samples matched those reported in the description of Myxobolus neurofontinalis from North Carolina. A 1057-bp fragment of the SSU rDNA from myxospores collected from Brook Trout in PEI was identical to an isolate of M. neurofontinalis (MN191598) collected previously from the type locality, New River basin, North Carolina. Histological sections confirmed infections were intercellular in the central nervous system. Minimal host response was observed, with only sparse mononuclear inflammatory infiltrates present at the periphery of and within dispersed myxospores, suggesting that infections are not pathogenic to Brook Trout.
Conclusion
Myxospores were identified as M. neurofontinalis, which was previously described from the central nervous system of Brook Trout from the New River basin, North Carolina, USA. This constitutes the first time M. neurofontinalis has been documented outside of the New River basin in North Carolina
A model naphthenic acid decouples oxidative phosphorylation through selective inhibition of mitochondrial complex activity
No full textThe naphthenic acid fraction compound (NAFC), 3,5-dimethyladamantane-1-acetic acid, was tested for its ability to uncouple mitochondrial oxidative phosphorylation. Mitochondria isolated from rainbow trout (Oncorhynchus mykiss) liver were exposed to 3,5-dimethyladamantane-1-acetic acid in state 3 and 4 respiration, and mitochondrial membrane potential were quantified. Electron transport chain (ETC) protein complexes were isolated using pharmacological agents and inhibitors, and their activities measured. The NAFC compound completely inhibited states 3 and 4 respiration with an IC50 of 0.77 and 1.01 mM, respectively. The NAFC compound partially uncoupled mitochondrial membrane potential in state 3 and 4 respiration with an IC50 of 2.19 and 1.73 mM, respectively. The NAFC impaired the activities of ETC protein complexes with a 9.5-fold range in sensitivity. The relative inhibitory effect of the ETC protein complexes to NAFC was CIV≥CI>CIII>CII. The impairment of mitochondrial oxidative phosphorylation by adamantane 3,5-dimethyladamantane-1-acetic acid is mediated via its inhibition of ETC protein complexes.NSERC Discover
International student's perception of the islandness, culture and identity in Prince Edward Island, Canada
No full textThe study examined international students' perception of islandness, culture, and identity in Prince Edward Island (PEI), Canada. This research aimed to evaluate how these perceptions influenced their cultural adaptation. Data were collected from 93 participants via an online survey and analyzed using descriptive and inferential statistics. Findings revealed diverse attributes based on gender, age, and origin, with African participants comprising 36.3% and Asians 22.9%. Before relocation, the internet (48%) and social media (32%) were the primary information sources about PEI. Key experiences included a strong sense of community (66%) and exposure to coastal culture (40%). Cultural adjustment was mixed, with 26.5% finding it easy, 34.5% challenging, and 16.8% neutral. Crucial integration factors included social support networks (43.4%), community involvement (37.2%), and maintaining cultural traditions (38.1%). The study provided insights into international students' evolving experiences of PEI's culture and identity. Participants faced several challenges, with 39% reporting difficulty adapting to the island's weather and climate, characterized by cold winters and mild summers. Language barriers and academic differences were cited by 10% of participants each, while 23% highlighted challenges in socialization and building friendships. Accessing rural communities posed difficulties for 18% of participants. These challenges reflect various aspects of adjustment to life on PEI, including environmental factors, cultural differences, educational transitions, social integration, and geographic accessibility. Addressing these challenges requires targeted support and resources to assist individuals in acclimating to the island's unique characteristics and fostering a sense of community belonging. Language proficiency, cited by 17% as critical, facilitated communication and integration. Government and legal support, noted by 6%, helped navigate bureaucratic processes. Correlation analysis highlighted significant relationships between students' pre-arrival knowledge, on-island experiences, cultural adjustments, and views on islandness, culture, and identity. There were strong correlations between PEI's unique identity and its geography, landscape, arts, and Mi'kmaq influence. Effective government efforts in promoting and preserving island culture were positively linked to perceptions of PEI's unique identity. High-quality education correlated with positive impacts on the local community, while pre-arrival cultural perceptions significantly affected students' adjustment and personal growth. The study concludes that a strong connection to PEI's unique identity aids cultural adaptation. It calls for further research into specific aspects of PEI's identity affecting students. It further suggests interventions like cultural sensitivity training and support services to enhance their adaptation experience. Despite its robust methodology, limitations such as response bias and lack of qualitative data highlight areas for improvement in future studies
Policy capacity research: An overview and bibliography of the international literature, 1978 to 2023
No full textThe purpose of this article is to provide an overview and bibliography of international policy capacity research that has developed over the past 40 years and to highlight themes that constitute the field. Through an international and multi-disciplinary synthesis of 311 English abstracts in 172 peer-reviewed journals, we find that policy capacity research has been driven by a handful of widely cited researchers, maintained a predominantly qualitative methodology, and focused on governments located in the West. Empirical research is needed to understand the dynamics of policy capacity outside of governments in the West, with a focus on developing actionable recommendations for practitioners to improve the quality of public policy in their respective jurisdictions. This paper fulfils the need for a comprehensive bibliography of policy capacity research for use by both academics and practitioners
Transforming artistic practice: Collingwood, Adorno, and the diseases of the mind
No full textThis paper addresses the views of R.G. Collingwood and Theodor Adorno on the role of amusement and art in what each of them saw as the crisis of contemporary Western civilization. We will begin by showing how the aesthetic theories of Collingwood and Adorno develop out of their shared concerns about the harmful effects of amusement and bad art on the consciousness of human beings. We will argue that a productive dialogue between these two figures clarifies that the value of art consists in its ability to remedy the corruption of the mental and emotional lives of human beings and in helping to fashion a different social and political order. As part of this, we will show how, despite appearances, Adorno’s aesthetic cognitivism and Collingwood’s expression theory of art agree with and complement one another in significant ways. In establishing this point, this work will leave us with an understanding of art that is more comprehensive and better equipped to address the crisis of contemporary Western society
Splitting light pollution: Wavelength effects on the activity of two sandy beach species
No full textArtificial Light at Night (ALAN) threatens to disrupt most natural habitats and species, including those in coastal settings, where a growing number of studies have identified ALAN impacts. A careful examination of the light properties behind those impacts is important to better understand and manage the effects of this stressor. This study focused on ALAN monochromatic wavelengths and examined which types of light spectra altered the natural activity of two prominent coastal species from the Pacific southeast: the talitroid amphipod Orchestoidea tuberculata and the oniscoid isopod Tylos spinulosus. We compared the natural daylight/night activity of these organisms with the one they exhibit when exposed to five different ALAN wavelengths: lights in the violet, blue, green, amber, and red spectra. Our working hypothesis was that ALAN alters these species’ activity at night, but the magnitude of such impact differs depending on light wavelengths. Measurements of activity over 24 h cycles for five consecutive days and in three separate experiments confirmed a natural circadian activity pattern in both species, with strong activity at night (∼90% of probability) and barely any activity during daylight. However, when exposed to ALAN, activity declined significantly in both species under all light wavelengths. Interestingly, amphipods exhibited moderate activity (∼40% of probability) when exposed to red lights at night, whereas isopods shifted some of their activity to daylight hours in two of the experiments when exposed to blue or amber lights, suggesting a possible alteration in this species circadian rhythm. Altogether, our results were consistent with our working hypothesis, and suggest that ALAN reduces night activity, and some wavelengths have differential effects on each species. Differences between amphipods and isopods are likely related to their distinct adaptations to natural low-light habitat conditions, and therefore distinct sensitivity to ALAN
Synergies of co-infecting pathogens, sea lice (Lepeophetheirus salmonis) and Moritella viscosa, are impacted by exposure order, and host response to initial infection
No full textSea lice infestations and winter ulcer disease caused by Moritella viscosa are two major challenges for the Atlantic salmon (Salmo salar) aquaculture industry. Despite their common tropisms for the skin/muscle, we know very little about the interaction between these two significant pathogens. The objective of this study was to elucidate the transcriptomic response of Atlantic salmon to sea louse (Lepeophtheirus salmonis) and M. viscosa under single infection and different scenarios of co-infection (i.e., first, L. salmonis and then, M. viscosa and vice versa). After exposure, sampling was performed from the infestation site as well as the adjacent area on fish skin, followed by transcriptome analysis. RNA-seq analysis revealed that infection with either L. salmonis or M. viscosa induced a significant immune response from the skin and resulted in extensive transcriptomic changes. More differentially expressed genes (DEGs) were detected at M. viscosa lesion sites compared to L. salmonis attachment sites. In addition, the effect of the infection order was evaluated. Interestingly, we found that primary infection with lice was associated with a significantly higher number of DEGs during the co-infection process on fish skin compared to the fish first infected with M. viscosa (721 and 5336 DEGs from lice attachment and M. viscosa lesion sites, respectively, vs 291 and 3601 DEGs from lice attachment and M. viscosa lesion sites, respectively). We also found that lice infection caused localized effects on the skin of Atlantic salmon, while single infection with M. viscosa caused a moderate systemic impact and inhibited the tissue repair function of the skin, leading to severe ulceration. In addition, the C-type lectin receptor signaling pathway was drastically activated at the lice attachment sites during both lice alone- and co-infections, regardless of the order of infections, and similar results were observed in M. viscosa infection at both lesion and adjacent sites, indicating that this pathway played an essential role for immunity in Atlantic salmon. A more intense inflammatory and immune response was also observed at M. viscosa lesion sites. These results will promote our understanding of the immune interactions between L. salmonis and M. viscosa during the co-infection process and provide insights for the development of preventive and treatment strategies for these pathogens in salmonid aquaculture
Non-fourier bioheat transfer analysis in brain tissue during interstitial laser ablation: Analysis of multiple influential factors
No full textThis work presents the dual-phase lag-based non-Fourier bioheat transfer model of brain tissue subjected to interstitial laser ablation. The finite element method has been utilized to predict the brain tissue's temperature distributions and ablation volumes. A sensitivity analysis has been conducted to quantify the effect of variations in the input laser power, treatment time, laser fiber diameter, laser wavelength, and non-Fourier phase lags. Notably, in this work, the temperature-dependent thermal properties of brain tissue have been considered. The developed model has been validated by comparing the temperature obtained from the numerical and ex vivo brain tissue during interstitial laser ablation. The ex vivo brain model has been further extended to in vivo settings by incorporating the blood perfusion effects. The results of the systematic analysis highlight the importance of considering temperature-dependent thermal properties of the brain tissue, non-Fourier behavior, and microvascular perfusion effects in the computational models for accurate predictions of the treatment outcomes during interstitial laser ablation, thereby minimizing the damage to surrounding healthy tissue. The developed model and parametric analysis reported in this study would assist in a more accurate and precise prediction of the temperature distribution, thus allowing to optimize the thermal dosage during laser therapy in the brain.Politecnico di MilanoEuropean Research Council (ERC)Fondazione Caripl