Development of a bi-national Great Lakes coastal wetland and land use map using three-season PALSAR and landsat imagery

Methods using extensive field data and three-season Landsat TM and PALSAR imagery were developed to map wetland type and identify potential wetland stressors (i.e., adjacent land use) for the United States and Canadian Laurentian coastal Great Lakes. The mapped area included the coastline to 10 km inland to capture the region hydrologically connected to the Great Lakes. Maps were developed in cooperation with the overarching Great Lakes Consortium plan to provide a comprehensive regional baseline map suitable for coastal wetland assessment and management by agencies at the local, tribal, state, and federal levels. The goal was to provide not only land use and land cover (LULC) baseline data at moderate spatial resolution (20–30 m), but a repeatable methodology to monitor change into the future. The prime focus was on mapping wetland ecosystem types, such as emergent wetland and forested wetland, as well as to delineate wetland monocultures (Typha, Phragmites, Schoenoplectus) and differentiate peatlands (fens and bogs) from other wetland types. The overall accuracy for the coastal Great Lakes map of all five lake basins was 94%, with a range of 86% to 96% by individual lake basin (Huron, Ontario, Michigan, Erie and Superior)

Automated Coastal Ice Mapping with SAR Can Inform Winter Fish Ecology in the Laurentian Great Lakes

Many freshwater lakes in the temperate zone undergo annual freeze-thaw cycles. Climate change has disrupted these patterns and altered habitat for many species including ecologically, economically, and culturally valuable fish species. To understand the relationship between ice cover and aquatic species, suitable data can be derived from remote sensing. We developed a novel ice classification method with minimal user input using freely available Sentinel-1 data and an adjacent and time-coincident validation dataset. Using image object segmentation and a random forest classifier, ice conditions were classified correctly with >85% overall accuracy. Our ice mapping efforts coincided with a telemetry dataset of tagged Walleye (Sander vitreus) and Northern Pike (Esox lucius) in Hamilton Harbor in western Lake Ontario. Between years with low and high ice covers (2017 and 2019, respectively), we found Walleye appeared to reduce their area of movement when the harbor was covered in ice. Our ice mapping tool can provide a quick and consistent method for agencies to adopt for freshwater resource management as well as provide ice cover information in coastal areas that are important overwintering habitat for many fishes

A survey evaluating surgeons’ peri-operative usage of acetyl-salicylic acid (ASA) and their willingness to enroll their patients in a perioperative ASA randomized controlled trial

Purpose: Major cardiovascular complications associated with noncardiac surgery represent a substantial population health problem for which there are no established efficacious and safe prophylactic interventions. Acetyl-salicylic acid (ASA) represents a promising intervention. The objective of this study was to determine surgeons’ perioperative usage of ASA, and if they would enrol their patients in a perioperative ASA randomized controlled trial (RCT). Methods: Cross-sectional survey of all practicing Canadian general, orthopedic, and vascular surgeons. Our mailed, self-administered survey asked surgeons to consider only their patients who were at risk of a major perioperative cardiovascular complication. Results: The response rate was 906/1854 (49%). For patients taking ASA chronically, there was marked variability regarding ASA continuation prior to surgery amongst the general and orthopedic surgeons, whereas 76% of vascular surgeons continued ASA in 81-100% of their patients. For patients not taking ASA chronically, approaches to starting ASA prior to surgery were variable amongst the vascular surgeons, whereas 70% of general and 82% of orthopaedic surgeons did not start ASA. For patients taking ASA chronically, 73% of general surgeons, 70% of orthopaedic surgeons, and 36% of vascular surgeons would allow at least 40% of their patients to participate in a perioperative RCT comparing stopping versus continuing ASA. For patients not taking ASA chronically, most general (76%), orthopaedic (67%), and vascular (51%) surgeons would allow at least 40% of their patients to participate in a perioperative RCT comparing starting ASA versus placebo. Conclusion: This national survey demonstrates that perioperative ASA usage as reported by surgeons is variable, identifying the need for, and community interest in, a large perioperative ASA trial

Luminescent and electronic properties of stilbenoid NCN-pincer PtII compounds

A series of novel 4,4'-disubstituted organic-organometallic stilbenes were synthesized, that is, the 4'-substituted stilbenoid- NCN-pincer platinum(II) complexes [PtCl(NCN-R-4)] (NCN-R-4 = [C6H2(CH2NMe2)2-2,6-R-4]- in which R = C2H2C6H4-R'-4' with R' = NMe2, OMe, SiMe3, H, I, CN, NO2) (1-7). In these compounds the PtCl grouping can be considered to be present as a donor substituent. Their synthesis involved a Horner-Wadsworth-Emmons reaction of [PtCl(NCN-CHO-4)] (9) with the appropriate phosphonate ester derivatives (8a-g). Under these reaction conditions, the C-Pt bond in aldehyde 9 was not affected, and the platinated stilbene products were obtained in 53-90% yield. The solidstate structures of complexes 1, 2 and 5-7 were determined by single-crystal X-ray diffraction, which revealed interesting bent conformations for 2, 5 and 7. Linear correlations were found between both the 13C{1H} (C ipso to Pt) and the 195Pt{1H} NMR chemical shift and the Hammett σp value of the R' substituent; therefore, these NMR shifts can be used as a qualitative probe for the electronic properties of the delocalized π-system to which it is connected. The platinum-stilbene complexes were investigated for charge-transfer properties in solvents of different polarity. The luminescent properties, shown by donor-acceptor complexes 1, 6 and 7, were investigated by fluorescence spectroscopy, and the complexes showed positive solvatochromism, which indicates dipolar character of the excited state. The excited state lifetimes, which were in the picosecond range, and the quantum yields (ranging from 0.002 to 0.2) were also determined for these complexes. It was established that the presence of the transition metal favours nonradiative decay from the excited state to the ground state