canadian light source

We have previously reported the design of a portable 109Cd x-ray fluorescence (XRF) skin iron measurement system with a low detection limit of 1.35 μg Fe per g of tissue, which delivers a skin surface dose of 1.1 mSv in iron overload and iron deficiency disease. The system has been found to be precise but must also provide accurate measurements of iron levels in the skin. 
This article describes testing of the system's accuracy. Ten pigskin samples were measured using both the portable XRF system and ICP-MS analysis...

CONTEXT: Artificial light at night (ALAN) is increasing worldwide, with many ecological effects. Aerial insectivores may benefit from foraging on insects congregating at light sources. However, ALAN could negatively impact them by increasing nest visibility and predation risk, especially for ground-nesting species like nightjars ( Caprimulgidae ). OBJECTIVES: We tested predictions based on these two alternative hypotheses, potential foraging benefits vs potential predation costs of ALAN, for two nightjar species in British Columbia: Common Nighthawks ( Chordeiles minor ) and Common Poorwills ( Phalaenoptilus nuttallii )...

BACKGROUND: The COVID-19 pandemic necessitated public health policies to limit human mobility and curb infection spread. Human mobility, which is often underestimated, plays a pivotal role in health outcomes, impacting both infectious and chronic diseases. Collecting precise mobility data is vital for understanding human behavior and informing public health strategies. Google's GPS-based location tracking, which is compiled in Google Mobility Reports, became the gold standard for monitoring outdoor mobility during the pandemic...

Synchrotron X-ray imaging and spectroscopy techniques were used for studying changes during post-harvest storage of food grains. Three varieties (AAC Spitfire, CDC Defy, and AAC Stronghold) of the Canada Western Amber Durum (CWAD) wheat class were stored for five weeks at 17 % moisture content (wb). Control (dry) and stored moistened seeds were analyzed for biochemical and nutritional changes using synchrotron bulk X-ray fluorescence spectroscopy (SR-XRF), X-ray fluorescence imaging (SR-XFI), and mid-infrared (mid-IR) spectroscopy at the Canadian Light Source (CLS), Saskatoon, SK...

Four varieties of barley (Esma, AC Metacalf, Tradition, and AB Cattlelac), representing four Canadian barley classes, were stored at 17% moisture content (mc) for 8 week. Stored barely was characterized using synchrotron X-ray phase contrast microcomputed tomography, synchrotron X-ray fluorescence imaging, and mid-infrared spectroscopy at the Canadian Light Source, Saskatoon. The deterioration was observed in all the selected varieties of barley at the end of 8 week of storage. Changes due to spoilage over time were observed in the grain microstructure and its nutrient distribution and composition...

Emerald ash borer (EAB) has killed millions of ash trees in the United States and Canada, yet impacts on terrestrial-aquatic linkages are largely unknown. Ash tree death along streams creates canopy gaps, increasing light to riparian plants and potentially affecting organic matter subsidies. Six EAB-related canopy gaps along streams across a gradient of timing of EAB invasion in Michigan were characterized for coarse woody material (CWM), terrestrial and aquatic leaf litter and their associated bacterial communities, and macroinvertebrates upstream, downstream, and at the center of the gap...

The new compound Ba6 Si2 Se12 was synthesized, and the crystal structure and physical properties are reported here. Ba6 Si2 Se12 adopts a new structure type in the triclinic P 1̄ space group with the lattice parameters a = 9.1822(7) Å, b = 12.2633(14) Å, c = 12.3636(18) Å, α = 109.277(3)°, β = 104.734(2)°, and γ = 100.4067(16)°. Notably, the structure features disordered Se2 2- dumbbells that have also been observed in the germanium selenide with the analogous stoichiometry (Ba6 Ge2 Se12 )...

OBJECTIVES: To examine whether there has been a change in the number of therapeutically important new medicines not being introduced into the Canadian market in light of the December 2017 announcement of regulatory changes to lower Canadian prices. METHODS: A list was compiled of medicines approved by the Food and Drug Administration (FDA) between 2014-2021 but not submitted to Health Canada. The therapeutic value of these medicines was assessed based on evaluations by two independent sources...

The goal of the current study is to enhance the hemocompatibility of polyethersulfone (PES) membranes using heparin immobilization. Heparin was immobilized covalently and via electrostatic interaction with the positively charged PES surface (pseudo-zwitterionic (pZW) complex) to investigate the influence of each method on the membrane hemocompatibility. In situ synchrotron radiation micro-computed tomography (SR-µCT) imaging, available at the Canadian Light Source (CLS), was used to critically assess the fibrinogen adsorption to the newly synthesized membranes qualitatively and quantitatively using an innovative synchrotron-based X-ray tomography technique...

Basic Multicellular Units (BMUs) conduct bone remodeling, a critical process of tissue turnover which, if imbalanced, can lead to disease, including osteoporosis. Parathyroid hormone (PTH 1-34; Teriparatide) is an osteoanabolic treatment for osteoporosis; however, it elevates the rate of intra-cortical remodeling (activation frequency) leading, at least transiently, to increased porosity. The purpose of this study was to test the hypothesis that PTH not only increases the rate at which cortical BMUs are initiated but also increases their progression (Longitudinal Erosion Rate; LER)...

Since the first confirmation of quantum monodromy in NCNCS (B. P. Winnewisser et al. , Report No. TH07 in 60th International Symposium on Molecular Spectroscopy, Columbus, OH, (2005) and B. P. Winnewisser et al. , Phys. Rev. Lett. , 2005, 95 , 243002) we have continued to explore its implications for the quantum structure of molecules. To confirm quantum monodromy bending-vibrational + axial-rotational quantum energy level information is needed. This was not directly available from the pure a-type rotational transitions available in 2005...

OBJECTIVE: To identify characteristics and visual outcomes of coagulase-negative staphylococci (CoNS) endophthalmitis in the era after the Endophthalmitis Vitrectomy Study. DESIGN: Single-centre retrospective analysis. PARTICIPANTS: Forty-two samples from 40 patients with documented CoNS endophthalmitis. METHODS: Visual acuity outcomes of patients with CoNS endophthalmitis were assessed in relation to species and type of treatment instituted (e...

BACKGROUND: Electron synchrotrons produce x-ray beams with dose rates orders of magnitude greater than conventional x-ray tubes and with beam sizes on the order of a few millimeters. These characteristics put severe challenges on current dosimeters to accurately realize absorbed dose or air kerma. PURPOSE: This work seeks to investigate the suitability of a novel aluminum-based calorimeter to determine absorbed dose to water with an uncertainty significantly smaller than currently possible with conventional detectors...

BACKGROUND: Cyanobacteria and eukaryotic phytoplankton produce long-chain alkanes and generate around 100 times greater quantities of hydrocarbons in the ocean compared to natural seeps and anthropogenic sources. Yet, these compounds do not accumulate in the water column, suggesting rapid biodegradation by co-localized microbial populations. Despite their ecological importance, the identities of microbes involved in this cryptic hydrocarbon cycle are mostly unknown. Here, we identified genes encoding enzymes involved in the hydrocarbon cycle across the salinity gradient of a remote, vertically stratified, seawater-containing High Arctic lake that is isolated from anthropogenic petroleum sources and natural seeps...

It is important to know the mineral distribution in cereal grains for nutritional improvement or genetic biofortification. Distributions and intensities of micro-elements (Mn, Fe, Cu, and Zn) and macro-elements (P, S, K and Ca) in Arborg oat were investigated using synchrotron-based on X-ray fluorescence imaging (XFI). Arborg oat provided by the Crop Development Center (CDC, Aaron Beattie) of the University of Saskatchewan for 2D X-ray fluorescence scans were measured at the BioXAS-Imaging beamline at the Canadian Light Source...

Protein bound uremic toxins (PBUTs) are small substances binding to larger proteins, mostly human serum albumin (HSA), and are challenging to remove by hemodialysis (HD). Among different classes of PBUTs, p-cresyl sulfate (PCS) is the most widely used marker molecule and major toxin, as 95% is bound to HSA. PCS has a pro-inflammatory effect and increases both the uremia symptom score and multiple pathophysiological activities. High-flux HD to clear PCS leads to serious loss of HSA, which results in a high mortality rate...

Instructors in organized physical activity classes can be a source of social support through their relationships with participants, influence on participants' interactions with each other, and design of activities. Grounded in interpretive description, the objective of this study was to examine older adults' experiences of and their perspectives on group physical activity instructors' supportive behaviors. Observations of 16 group physical activity classes (N = 295) and focus groups or interviews with N = 38 class participants aged ≥ 55 (n = 29 women) were conducted at four municipal recreation facilities in a Canadian city...

The rotational spectrum of 2-furonitrile (2-cyanofuran) has been obtained from 140 to 750 GHz, capturing its most intense rotational transitions at ambient temperature. 2-Furonitrile is one of two isomeric cyano-substituted furan derivatives, both of which possess a substantial dipole moment due to the cyano group. The large dipole of 2-furonitrile allowed over 10 000 rotational transitions of its ground vibrational state to be observed and least-squares fit to partial octic, A- and S-reduced Hamiltonians with low statistical uncertainty (σfit = 40 kHz)...

Comprehensive understanding of protein adsorption phenomenon on membrane surface during hemodialysis (HD) is one of the key moments for development of hemocompatible HD membrane. Though many mechanisms and kinetics of protein adsorption on some surface have been studied, we are still far away from complete understanding and control of this process, which results in a series of biochemical reactions that causes severe complications with health and even the death among HD patients. The aim of this study is to conduct quantitative analysis of competitive adsorption tendency of human serum protein on polyether sulfone (PES) clinical dialysis membrane...

Plant-pathogenic bacteria in the Ralstonia solanacearum species complex (RSSC) cause highly destructive bacterial wilt disease of diverse crops. Wilt disease prevention and management is difficult because RSSC persists in soil, water, and plant material. Growers need practical methods to kill these pathogens in irrigation water, a common source of disease outbreaks. Additionally, the R. solanacearum race 3 biovar 2 (R3bv2) subgroup is a quarantine pest in many countries and a highly regulated select agent pathogen in the United States...