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Virulence of emerging arthrotropic avian reoviruses correlates with their ability to activate and traffic interferon-γ producing cytotoxic CD8+ T cells into gastrocnemius tendon
No full textNewly emerging arthrotropic avian reoviruses (ARVs) are genetically divergent, antigenically heterogeneous, and economically costly. Nevertheless, the mechanism of emerging ARV-induced disease pathogenesis and potential differences in virulence between virus genotypes have not been adequately addressed. In this study, the life cycle of ARV, including the formation of cytoplasmic ARV neo-organelles, paracrystalline structures, and virus release mechanisms, were characterized in the infected host cell by transmission electron microscopy (TEM). In addition, progressive changes in the structure of infected cells were investigated by time-lapse and field emission scanning electron (FE-SE) microscopy. ARVs from the four genotypic cluster groups included in the study caused gross and microscopic lesions in the infected birds. Marked infiltration of γδT cells, CD4+ and CD8+ T lymphocytes were observed in ARV infected tendon tissues starting day 3 post-infection. The ARV variant from genotype cluster-2 triggered significantly high trafficking of IFN-γ producing CD8+ T lymphocytes in tendon tissues and concomitantly showed high morbidity and severe disease manifestations. In contrast, the ARV variant from genotype cluster-4 was less virulent, caused milder disease, and accompanied less infiltration of IFN-γ producing CD8+ T cells. Interestingly, when we blunted antiviral immune responses using clodronate liposomes (which depletes antigen-presenting cells) or cyclosporin (which inhibits cytokine production that regulates T-cell proliferation), significantly lower IFN-γ producing CD8+ T cells infiltrated into tendon tissues, resulting in reduced tendon tissues apoptosis and milder disease manifestations. In summary, these data suggest that the degree of ARV virulence and tenosynovitis/arthritis are potentially directly associated with the ability of the virus to traffic massive infiltration of cytotoxic CD8+ T cells into the infected tissues. Moreover, the ability to traffic cytotoxic CD8+ T cells into infected tendon tissues and the severity of tenosynovitis differ between variants from different ARV genotype cluster groups. However, more than one virus isolate per genotype group needs to be tested to further confirm the association of pathogenicity with genotype. These findings can be used to further examine the interaction of viral and cellular pathways which are essential for the pathogenesis of the disease at the molecular level and to develop effective disease control strategies.Natural Sciences and Engineering Research Council of CanadaSaskatchewan Agriculture Development FundChicken Farmers of Saskatchewan/Saskatchewan Chicken Industry Development Fun
An efficient navigation system for autonomous mobile robots in dynamic social environments
No full textIn this paper, we propose an efficient navigation framework for autonomous mobile robots in dynamic social environments. The main idea of the proposed enhanced dynamic window approach (EDWA) model is to combine the advantages of the dynamic window approach (DWA) technique and the hybrid reciprocal velocity obstacles (HRVO) technique by taking into account the output velocity vector of the HRVO method into the objective function of the conventional DWA model. The proposed EDWA model’s output is the efficient control command for the mobile robots. To validate the effectiveness of the proposed EDWA model, we conduct a series of experiments in both simulated and real-world environments. The results illustrate that our proposed EDWA model enables the robots to proactively and safely avoid dynamic obstacles in its vicinity
Prognostic impact of blood pressure change patterns on patients with aortic dissection after admission
No full textObjectives: Hypertension is a predominant risk factor for aortic dissection (AD), and blood pressure (BP) control plays a vital role in the management of AD. However, the correlation between BP change and the prognosis for AD remains unclear. This study aims to demonstrate the impact of BP change patterns on AD prognosis.
Methods: This retrospective study included AD patients at two institutions (Shanghai Ninth People's Hospital Affiliated with Shanghai Jiao Tong University School of Medicine and the Vascular Department of the First Affiliated Hospital of Anhui Medical University) between 2004 and 2018. The systolic BP (SBP) change patterns of these patients were analyzed by functional data analysis (FDA). The relationship between BP change patterns and the risk of adverse events (AEs) was assessed using survival analysis.
Results: A total of 458 patients with AD were eligible for analysis. The logistic regression analysis indicated that compared with that in patients with low SBP variation (SBPV), the incidence of AEs in patients with high SBPV was significantly higher (35.84 vs. 20.35%, OR 2.19, P < 0.001). The patients were divided into four categories (accelerating rise, accelerating drop, decelerating rise, and decelerating drop) based on their SBP patterns after FDA fitting. The results of Kaplan–Meier analysis showed that at the 15- and 20-min time points, the incidence of AEs in the decelerating-drop group was significantly lower than that in the accelerating-rise group (OR 0.19, P = 0.031 and OR 0.23, P = 0.050). However, at the 25- and 30-min time points, the difference between these four groups was not significant (OR 0.26, P = 0.08 and OR 0.29, P = 0.10).
Conclusions: This study classified AD patients into four groups according to the SBP change patterns the first 30 min following admission, of which those with accelerating rises in SBP are at the highest risk of AEs, while those with decelerating drops have the best prognosis in the first 24 h after admission. Clinical practitioners may benefit from analyzing patterns of in-hospital SBP.National Natural Science Foundation of ChinaClinical Research Program of Shanghai Ninth People's HospitalShanghai Science and Technology Innovation Action PlanClinical Research Plan of SHDCShanghai Ninth People's Hospital Nursing Fund ProjectShanghai Municipal Health Bureau ProjectOpen Research Program of National Facility for Translational Medicine (Shanghai)Fundamental research program funding of Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong university School of Medicin
Energy systems and energy sharing in traditional and sustainable archetypes of urban developments
No full textDiverse factors influence the energy profile of an urban development including density, shape of buildings and their types, energy demand, and available energy resources. A systematic investigation of the energy characteristics of urban areas, involves the determination of representative archetypes of urban developments. This study presents a comparison of energy performance and resources between two categories of traditionally built urban development building clusters (BCs) in the North American urban context, and neighborhood units (NUs) designed with various sustainable principles and considerations. The study presents a methodology to optimize the mix of energy resources of individual building clusters and neighborhoods, as well as the optimization of energy sharing among the individual urban units of each category. Optimal energy sharing is determined based on the best combination of energy deficit and energy surplus of various clusters and neighborhoods. The study shows that in general neighborhood units encompassing diverse building uses and designed to allow different amenities within a walking distance perform better than commonly built building clusters with low usage diversity. Highly diverse neighborhoods that combine large commercial areas to high density residential buildings can generate up to 84% of their annual electrical and up to 37% of their annual thermal consumption. PV generation accounts for major part of the electrical energy generation of both individual urban units (BCs and NUs) and combination of these units. This can reach up to 92% of the total energy consumption of some combinations of NUs, while the remaining energy requirement is fulfilled by wind and waste to energy (3.4% and 4.9%, respectively). On the other hand, the study shows that thermal energy is mostly supplied by alternative energy sources, since building surfaces prioritize the accommodation of PV modules.Natural Sciences and Engineering Research Council of Canad
Novel methodology of urban energy simulations integrating open-source platforms
No full textIn this research, a novel open-source methodology is presented to perform building cluster and neighborhood simulation by integrating individual archetypes building energy models (BEM). This methodology merges various building Energy Plus models employing a programming language. For the demonstration of generalized methodology, Matlab is used, however, methodology can be implemented by other programming languages such as Python. A given BEM can be employed multiple times to avoid its remodeling in a traditional cluster model setup. The proposed workflow is successfully validated for low, mid, and high-rise mixed-use building clusters with a maximum deviation of ± 2.70% in various annual performance parameters compared to the summation of individual BEM simulations. A sensitivity analysis is also performed to quantify the root mean square deviation (RMSD) between cluster and individual BEM simulations by varying building distance to height ratios along north–south and east–west axes. A significance index on a ten-point scale is proposed to evaluate the importance of cluster simulations over the individual BEM simulations (where the sum of individual BEM results can be used to replace cluster simulations). For instance, the significance index found is to be highest for high-rise building cluster, suggesting thus that building cluster simulations yield more adequate results than individual BEM simulations
Applications of simulation modelling to inform viral disease management in Canadian salmon aquaculture
No full textInfectious diseases are responsible for substantial economic losses in salmon aquaculture due to production losses from mortality, morbidity and reduced growth rates, and costs of outbreak prevention and mitigation. Two of the most concerning viral diseases affecting farmed salmon in Canada are infectious salmon anaemia (ISA) and infectious hematopoietic necrosis (IHN). These are region-specific in Canada, as ISA occurs in the Atlantic coast, while IHN is present in the Pacific coast. Despite epidemiologic differences between the two viruses, both can be transmitted between marine salmon farms in the water column. However, limited research has been conducted on the transmission dynamics of ISA virus (ISAV) and IHN virus (IHNV) among marine farmed salmon populations in Canada. Furthermore, some aspects of ISAV epidemiology and cost- effectiveness of its mitigation in Atlantic Canada require further investigation.
Research documented in this thesis aimed to provide additional insights about the epidemiology of ISAV in Atlantic Canada. A population-level descriptive study reported epidemiologic findings of an ISAV outbreak in the region. In two of the affected marine salmon farms both European and North American ISAV variants were simultaneously detected. In addition, we found presumptive evidence of emergence of a pathogenic ISAV variant from a non-pathogenic variant of the same genotype, based on detection of co- infection in one fish.
A simulation modelling framework was developed for the purpose of investigating the dynamics of waterborne pathogen transmission in marine salmon aquaculture. This framework allowed for development of models that simulate waterborne infection spread within net-pens, and between net-pens (both within and between farm sites), as well as surveillance, detection, and depopulation measures. Technical characteristics and structure of the framework were described, and a case study demonstrated the framework functionalities. This simulation tool addresses the lack of simulation models intrinsically adapted to the aquaculture context.
The newly-developed modelling framework was used to simulate IHNV incursions and subsequent spread along the coast of British Columbia and the implementation of a viral disease management plan (VDMP) by salmon companies. Different scenarios were explored to assess VDMP effectiveness compared with alternative mitigation measures. Research findings indicated that interventions crucial to contain IHN outbreaks were the use of an IHN vaccine with high population coverage and efficacy, the implementation of surveillance zones, and the pre-emptive depopulation of all net-pens in IHNV-infected farms. Comparisons between simulated scenarios indicated that the VDMP was effective in limiting IHNV spread and mitigating outbreaks across the region.
Finally, to help the salmon aquaculture industry plan for expansion of production capacity in Atlantic Canada, a simulation modelling approach was used to assess the cost- effectiveness of ISAV outbreak mitigation strategies, considering different percentages of active licensed farms. For each model scenario, direct costs of ISAV mitigation interventions were estimated from model outputs. Results demonstrated the importance of pre-emptive depopulation of all net-pens in ISAV-positive farms to effectively limit ISAV spread; however, this strategy increased costs of ISAV mitigation as production capacity expanded, suggesting that a moderate capacity increase (65% compared with 40% active farms) would be more cost-effective than a high capacity increase (90% active farms). Nevertheless, a cost-benefit analysis should be explored to substantiate this recommendation.
This research demonstrates the value of descriptive epidemiologic studies and simulation modelling in aquatic health management. Ultimately, research findings documented herein provide insights to inform policy and disease management decisions to reduce viral disease risk in Canadian salmon aquaculture
Mitigation of greenhouse gas emissions from agricultural fields through bioresource management
No full textEfficient bioresource management can alter soil biochemistry and soil physical properties, leading to reduced greenhouse gas (GHG) emissions from agricultural fields. The objective of this study was to evaluate the role of organic amendments including biodigestate (BD), biochar (BC), and their combinations with inorganic fertilizer (IF) in increasing carbon sequestration potential and mitigation of GHG emissions from potato (Solanum tuberosum) fields. Six soil amendments including BD, BC, IF, and their combinations BDIF and BCIF, and control (C) were replicated four times under a completely randomized block design during the 2021 growing season of potatoes in Prince Edward Island, Canada. An LI-COR gas analyzer was used to monitor emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from treatment plots. Analysis of variance (ANOVA) results depicted higher soil moisture-holding capacities in plots at relatively lower elevations and comparatively lesser volumetric moisture content in plots at higher elevations. Soil moisture was also impacted by soil temperature and rainfall events. There was a significant effect of events of data collection, i.e., the length of the growing season (p-value ≤ 0.05) on soil surface temperature, leading to increased GHG emissions during the summer months. ANOVA results also revealed that BD, BC, and BCIF significantly (p-value ≤ 0.05) sequestered more soil organic carbon than other treatments. The six experimental treatments and twelve data collection events had significant effects (p-value ≤ 0.05) on the emission of CO2. However, the BD plots had the least emissions of CO2 followed by BC plots, and the emissions increased with an increase in atmospheric/soil temperature. Results concluded that organic fertilizers and their combinations with inorganic fertilizers help to reduce the emissions from the agricultural soils and enhance environmental sustainability.Atlantic Canada Opportunities AgencyDepartment of Environment, Energy and Climate Action, Government of Prince Edward Islan
Early-life seizures modify behavioral response to ultrasonic vocalization playback in adult rats
No full textEarly-life seizures (ELS) are associated with autism spectrum disorder (ASD); however, due to a lack of effective treatments for ELS, it is not clear whether ELS plays a causal role, potentiates the ASD phenotype, or is the result of a common pathophysiology. Deficits in communications are a core feature of ASD. To isolate the impact of ELS on communication, we probed the behavioral consequences of a single episode of kainic acid-induced early-life seizures (KA-ELS) in male and female Sprague–Dawley (CD) rats. Deficits in auditory communication were observed in adult male rats as assessed by behavioral response to ultrasonic vocalization (USV) playback. Ultrasonic vocalizations are classified into two major categories – 50-kHz (positive) calls and 22-kHz (aversive) calls. Behavioral response was assessed via rat preference for different USV playback in a radial arm maze. Response to 22-kHz calls was not impacted by ELS while response to 50-kHz calls was impacted. All rats demonstrated positional preference for the arms adjacent to where 50-kHz calls were playing compared to background noise; however, male ELS rats demonstrated a greater positional preference for the arms adjacent to where 50-kHz calls were playing compared to male control rats. These studies demonstrate that responses to socially relevant auditory cues are chronically altered in adult male rats following a single episode of ELS. We speculate that these changes contribute to previously reported social deficits associated with ELS
Application of artificial neural networks to project reference evapotranspiration under climate change scenarios
No full textEvapotranspiration is sensitive to climate change. The main objective of this study was to examine the response of reference evapotranspiration (ET0) under various climate change scenarios using artificial neural networks and the Canadian Earth System Model Second Generation (CanESM2). The Hargreaves method was used to calculate ET0 for western, central, and eastern parts of Prince Edward Island using their two input parameters: daily maximum temperature (Tmax), and daily minimum temperature (Tmin). The Tmax and Tmin were downscaled with the help of statistical downscaling model (SDSM) for three future periods 2020s (2011-2040), 2050s (2041-2070), and 2080s (2071-2100) under three representative concentration pathways (RCP’s) including RCP 2.6, RCP P4.5, and RCP 8.5. Temporally, there were major changes in Tmax, Tmin, and ET0 for the 2080s under RCP8.5. The temporal variations in ET0 for all RCPs matched the reports in the literature for other similar locations. For RCP8.5, it ranged from 1.63 (2020s) to 2.29 mm/day (2080s). As a next step, a one-dimensional convolutional neural network (1D-CNN), long-short term memory (LSTM), and multilayer perceptron (MLP) were used for estimating ET0. High coefficient of correlation (r > 0.95) values for both calibration and validation periods showed the potential of the artificial neural networks in ET0 estimation. The results of this study will help decision makers and water resource managers in future quantification of the availability of water for the island and to optimize the use of island water resources on a sustainable basis
Critically ill patients: Family experiences of interfacility transfers from rural to urban centers and impact on family relationships
No full textA critical illness event is intensely stressful for family members and can lead to negative psychological, emotional, social and financial consequences. In geographically rural areas, critically ill patients may require an interfacility transfer to an urban centre for advanced critical care services. In this context, research suggests that these family members from rural areas experience additional burdens, yet little is known about these experiences. An interpretive phenomenological approach was used to explore lived experiences of family members from rural areas whose critically ill relative undergoes an interfacility transfer to an urban centre for advanced critical care services. Participants described feelings of vulnerability in the urban centre, the need to protect the critically ill patient and other relatives, maintaining responsibilities at home, navigating family relationships, and a loss of connection during the transfer window. These findings may better position nurses to address family members’ stress and anxiety during this experience