Investigation of total gaseous mercury in the atmosphere of the Great Lakes and St. Lawrence River basin.

Mercury (Hg) is a highly toxic pollutant, and it can undergo long-range transport in the atmosphere. Hg is a pollutant of concern because of its tendency to accumulate and concentrate in biota. In this study, a statistical analysis of total gaseous mercury (TGM) was carried out using seven years of measurements at three Canadian Atmospheric Mercury Measurement Network (CAMNet) sites in the Great Lakes basin and three years measurements at two CAMNet sites in the St. Lawrence River basin. The average TGM concentrations ranged from 1.59 +/- 0.24 to 1.84 +/- 0.39 ng m-3 at the five sites. Two of the sites, Point Petre and St. Anicet, have significantly higher (p \u3c 0.05) TGM concentrations in the Great Lake basin and St. Lawrence River basin, respectively. Large Hg evasion from Lake Ontario is a primary contributor for Point Petre, while nearby industrial and metropolitan areas may contribute more anthropogenic inputs to St. Anicet. Seasonal variability was detected at all five sites with a similar winter high pattern. Higher TGM concentrations were observed at Point Petre in summer, whereas lower TGM values were observed during summertime at the other four sites. In terms of diurnal pattern, minimum TGM concentrations occur before early morning and reach maximum near noon at most sites except for St. Anicet with night peak. The diurnal pattern in summer is more prominent than in other seasons. (Abstract shortened by UMI.)Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .Y68. Source: Masters Abstracts International, Volume: 44-01, page: 0456. Thesis (M.A.Sc.)--University of Windsor (Canada), 2005

GUSOT: Green and Unsupervised Single Object Tracking for Long Video Sequences

Supervised and unsupervised deep trackers that rely on deep learning technologies are popular in recent years. Yet, they demand high computational complexity and a high memory cost. A green unsupervised single-object tracker, called GUSOT, that aims at object tracking for long videos under a resource-constrained environment is proposed in this work. Built upon a baseline tracker, UHP-SOT++, which works well for short-term tracking, GUSOT contains two additional new modules: 1) lost object recovery, and 2) color-saliency-based shape proposal. They help resolve the tracking loss problem and offer a more flexible object proposal, respectively. Thus, they enable GUSOT to achieve higher tracking accuracy in the long run. We conduct experiments on the large-scale dataset LaSOT with long video sequences, and show that GUSOT offers a lightweight high-performance tracking solution that finds applications in mobile and edge computing platforms

Optimization of a Decellularization/Recellularization Strategy for Transplantable Bioengineered Liver

The liver is a complex organ that requires constant perfusion for the delivery of nutrients and oxygen and the removal of waste in order to survive. Efforts to recreate or mimic the liver microstructure via a ground-up approach are essential for liver tissue engineering. A decellularization/recellularization strategy is one of the approaches aiming at the possibility of producing a fully functional organ with in vitro-developed construction for clinical applications to replace failed livers, such as end-stage liver disease (ESLD). However, the complexity of the liver microarchitecture along with the limited suitable hepatic component, such as the optimization of the extracellular matrix (ECM) of the biomaterials, the selection of the seed cells, and development of the liver-specific three-dimensional (3D) niche settings, pose numerous challenges. In this chapter, we have provided a comprehensive outlook on how the physiological, pathological, and spatiotemporal aspects of these drawbacks can be turned into the current challenges in the field, and put forward a few techniques with the potential to address these challenges, mainly focusing on a decellularization-based liver regeneration strategy. We hypothesize the primary concepts necessary for constructing tissue-engineered liver organs based on either an intact (from a naïve liver) or a partial (from a pretreated liver) structure via simulating the natural development and regenerative processes

Revealing chronic disease progression patterns using Gaussian process for stage inference.

OBJECTIVE: The early stages of chronic disease typically progress slowly, so symptoms are usually only noticed until the disease is advanced. Slow progression and heterogeneous manifestations make it challenging to model the transition from normal to disease status. As patient conditions are only observed at discrete timestamps with varying intervals, an incomplete understanding of disease progression and heterogeneity affects clinical practice and drug development. MATERIALS AND METHODS: We developed the Gaussian Process for Stage Inference (GPSI) approach to uncover chronic disease progression patterns and assess the dynamic contribution of clinical features. We tested the ability of the GPSI to reliably stratify synthetic and real-world data for osteoarthritis (OA) in the Osteoarthritis Initiative (OAI), bipolar disorder (BP) in the Adolescent Brain Cognitive Development Study (ABCD), and hepatocellular carcinoma (HCC) in the UTHealth and The Cancer Genome Atlas (TCGA). RESULTS: First, GPSI identified two subgroups of OA based on image features, where these subgroups corresponded to different genotypes, indicating the bone-remodeling and overweight-related pathways. Second, GPSI differentiated BP into two distinct developmental patterns and defined the contribution of specific brain region atrophy from early to advanced disease stages, demonstrating the ability of the GPSI to identify diagnostic subgroups. Third, HCC progression patterns were well reproduced in the two independent UTHealth and TCGA datasets. CONCLUSION: Our study demonstrated that an unsupervised approach can disentangle temporal and phenotypic heterogeneity and identify population subgroups with common patterns of disease progression. Based on the differences in these features across stages, physicians can better tailor treatment plans and medications to individual patients

Can changing the timing of outdoor air intake reduce indoor concentrations of traffic-related pollutants in schools?

Traffic emissions have been associated with a wide range of adverse health effects. Many schools are situated close to major roads, and as children spend much of their day in school, methods to reduce traffic‐related air pollutant concentrations in the school environment are warranted. One promising method to reduce pollutant concentrations in schools is to alter the timing of the ventilation so that high ventilation time periods do not correspond to rush hour traffic. Health Canada, in collaboration with the Ottawa‐Carleton District School Board, tested the effect of this action by collecting traffic‐related air pollution data from four schools in Ottawa, Canada, during October and November 2013. A baseline and intervention period was assessed in each school. There were statistically significant (P < 0.05) reductions in concentrations of most of the pollutants measured at the two late‐start (9 AM start) schools, after adjusting for outdoor concentrations and the absolute indoor–outdoor temperature difference. The intervention at the early‐start (8 AM start) schools did not have significant reductions in pollutant concentrations. Based on these findings, changing the timing of the ventilation may be a cost‐effective mechanism of reducing traffic‐related pollutants in late‐start schools located near major roads

Can changing the timing of outdoor air intake reduce indoor concentrations of traffic-related pollutants in schools?

Traffic emissions have been associated with a wide range of adverse health effects. Many schools are situated close to major roads, and as children spend much of their day in school, methods to reduce traffic-related air pollutant concentrations in the school environment are warranted. One promising method to reduce pollutant concentrations in schools is to alter the timing of the ventilation so that high ventilation time periods do not correspond to rush hour traffic. Health Canada, in collaboration with the Ottawa-Carleton District School Board, tested the effect of this action by collecting traffic-related air pollution data from four schools in Ottawa, Canada, during October and November 2013. A baseline and intervention period was assessed in each school. There were statistically significant (P \u3c 0.05) reductions in concentrations of most of the pollutants measured at the two late-start (9 AM start) schools, after adjusting for outdoor concentrations and the absolute indoor–outdoor temperature difference. The intervention at the early-start (8 AM start) schools did not have significant reductions in pollutant concentrations. Based on these findings, changing the timing of the ventilation may be a cost-effective mechanism of reducing traffic-related pollutants in late-start schools located near major roads. © 2015 Her Majesty the Queen in Right of Canada. Indoor Air published by John Wiley & Sons Ltd. Reproduced with the permission of the Minister of Health Canada

The miR-15/16 Cluster Is Involved in the Regulation of Vertebrate LC-PUFA Biosynthesis by Targeting pparγ as Demonostrated in Rabbitfish Siganus canaliculatus

Post-transcriptional regulatory mechanisms play important roles in the regulation of long-chain (≥ C20) polyunsaturated fatty acid (LC-PUFA) biosynthesis. Here, we address a potentially important role of the miR-15/16 cluster in the regulation of LC-PUFA biosynthesis in rabbitfish Siganus canaliculatus. In rabbitfish, miR-15 and miR-16 were both highly responsive to fatty acids affecting LC-PUFA biosynthesis and displayed a similar expression pattern in a range of rabbitfish tissues. A common potential binding site for miR-15 and miR-16 was predicted in the 3′UTR of peroxisome proliferator-activated receptor gamma (pparγ), an inhibitor of LC-PUFA biosynthesis in rabbitfish, and luciferase reporter assays revealed that pparγ was a potential target of miR-15/16 cluster. In vitro individual or co-overexpression of miR-15 and miR-16 in rabbitfish hepatocyte line (SCHL) inhibited both mRNA and protein levels of Pparγ, and increased the mRNA levels of Δ6Δ5 fads2, Δ4 fads2, and elovl5, key enzymes of LC-PUFA biosynthesis. Inhibition of pparγ was more pronounced with co-overexpression of miR-15 and miR-16 than with individual overexpression in SCHL. Knockdown of miR-15/16 cluster gave opposite results, and increased mRNA levels of LC-PUFA biosynthesis enzymes were observed after knockdown of pparγ. Furthermore, miR-15/16 cluster overexpression significantly increased the contents of 22:6n-3, 20:4n-6 and total LC-PUFA in SCHL with higher 18:4n-3/18:3n-3 and 22:6n-3/22:5n-3 ratio. These suggested that miR-15 and miR-16 as a miRNA cluster together enhanced LC-PUFA biosynthesis by targeting pparγ in rabbitfish. This is the first report of the participation of miR-15/16 cluster in LC-PUFA biosynthesis in vertebrates