Shedding light on the causes of arsenic contamination

An international team has used the Canadian Light Source at the University of Saskatchewan to uncover the elusive structure of two arsenic-containing compounds, information that can be used to prevent and predict arsenic contamination.

Arsenic occurs naturally in the environment, and it is present in ore deposits and the waste left behind by mining for gold, uranium, and other metals. The concern with arsenic-containing compounds, like yukonite and arseniosiderite, is that soil sources can find their way into waterways. Understanding how this happens on a structural level can help scientists — and industry — better understand how the two are formed and better protect the surrounding environment from potential arsenic contamination.

Discovered more than 100 years ago, yukonite and arseniosiderite, which are compounds of arsenic, calcium, iron and oxygen, have concealed their structure from scientists thanks to their low crystallinity. While it’s relatively easy to determine the structure of materials that have a high degree of crystallinity, because of the complexity in the way these minerals’ atoms are arranged, usual methods have come up short in painting a clear picture of their structure.

Using a special technique at the CLS called the pair distribution function (PDF), an international team of researchers from Canada, China, the USA, Italy, and Ireland was able to visualize for the first time how atoms are structured in samples of arseniosiderite, which is classified as semi-crystalline, and yukonite, which is considered a nano-crystalline mineral.

Read more on the CLS website

 Image: Specimen BM.62813 from the collections of the Natural History Museum, London 

Credit: © The Trustees of the Natural History Museum, London

Towards better LED lighting

Designing energy efficient, high output, perfectly tinted LEDs

SASKATOON – Scientists have combined experimental data gathered at the Canadian Light Source at the University of Saskatchewan and theoretical data to build deep insight into two types of light emitting crystals for next-generation LEDs.

“When we have means of creating more efficient lighting, this has a huge environmental impact,” says Alexander Moewes, Canada Research Chair in Materials Science with Synchrotron Radiation at the University of Saskatchewan, who cites that lighting accounts for 15-20% of global electricity consumption, and therefore for roughly 5% of worldwide greenhouse gas emissions.

Read more on the CLS website

Image: Tristan de Boer,  Patrick Braun, Ruhul Amin, Alexander Moewes and Amir Qamar outside the Physics building at USask

Turning straw into gold?

A more profitable and eco-friendly method for turning biomass into biochemicals and green hydrogen

Many have dreamed of being able to turn straw into gold like the fabled Rumpelstiltskin. While this may not be possible in the literal sense, scientists are using sunlight to turn straw into something more valuable.

With the aid of technology from the Canadian Light Source (CLS) at the University of Saskatchewan, Canadian researchers have made important advances to use the power of the sun to convert biomass like wheat straw into hydrogen fuel and value-added biochemicals. This method is more efficient, eco-friendly and lucrative.

Producing energy from biomass, or plant material, has been studied for more than four decades, said Dr. Jinguang Hu, assistant professor at the University of Calgary (UCalgary). The two most common processes are thermo-chemical and biological, but these are still carbon intensive and are not economically feasible.

Read more on the CLS website

Image: The UCalgary team is observing a photo-reactor that is being used for a photoreforming reaction with wheat straw. Left to right: Prof. Md Golam Kibria, Dr. Adnan Khan (Research Associate), Dr. Heng Zhao (Post doctoral fellow), Prof. Jinguang Hu.

Credit: Prof. Hu and Kibria group.

Scientists discover potential method to starve the bacteria that cause Tuberculosis

By deepening our understanding of how Tuberculosis bacteria feed themselves, University of Guelph researchers have identified a potential target for drug treatment. The team used the Canadian Light Source (CLS) at the University of Saskatchewan to image the bacteria in fine detail.

The infectious disease Tuberculosis (TB) is one of the leading causes of death worldwide. While rates of TB in Canada have remained relatively static since the 1980s, the disease disproportionately affects Indigenous populations. With TB-causing bacteria becoming increasingly resistant to antibiotics, researchers and drug makers are eager to find new, more effective treatments.

Researchers have known for some time that the bacteria that causes TB (Mycobacterium tuberculosis) uses our body’s cholesterol – a steroid – as a food source. Other relatives of the bacteria that do not cause disease share its ability to break down steroids. In this study, the University of Guelph team identified the structure of an enzyme (acyl CoA dehydrogenase) involved in steroid degradation in another member of the same bacteria family, called Thermomonospora curvata.

Read more on the CLS Website

Image: This rendering shows the shape of a tunnel (orange) where the substrate binds. Any drugs targeting this enzyme would need to fit to this pocket.

Canadian Light Source launches The Bison Project

The Canadian Light Source (CLS) at the University of Saskatchewan is launching The Bison Project, a research experience built with a reconciliation action framework for high school, adult basic education and undergraduate students.

The Bison Project integrates Traditional Knowledge and western science in a transformative research experience for First Nation, Métis, and Inuit students. The project seeks to reclaim and preserve the central and momentous historical contributions of First Nations, Métis and Inuit women towards saving bison from extinction through a holistic learning approach encompassing knowledge exchange and project-based learning.

This will include mail-in sample analysis of bison hair and grazing soil using CLS beamlines and multi-year projects with student-determined research. Students will participate in land-based sample gathering, research timeline development, and CLS beamline experiments exploring elemental mapping of bison hair and grazing soil.

The Bison Project will generate a collection of cultural expression resources to keep traditional knowledge alive through oral tradition.

Read more on the CLS website

Image: Adult bison and calves at Nachusa Grasslands.

Credit: The Nature Conservancy

Hummus for cows?

Identifying the best chickpea crops for cattle feed

While hummus used to be an exotic spread enjoyed only in the Middle East, it has become a staple in grocery stores throughout the world. Recently, the savory dish has gained popularity amongst a new fan base: herds of cows.

As chickpea production increases around the world, those crops not suitable for human consumption are being recycled into cattle feed as a partial replacement for soybean meal and cereal grains, explained Dr. Peiqiang Yu, a professor with the University of Saskatchewan (USask). “However, until now there was limited information about the nutritional values for this newly developed chickpea as ruminant feed,” he said.

In a recent study, Yu and colleagues showed that the Canadian Light Source (CLS) at USask can effectively image the molecular structure of chickpea seeds to determine which varieties have the highest nutritional value and would best serve as a feed for beef and dairy cattle.

Read more on the Canadian Light Source website

Image: Synchrotron techniques can offer insights into which chickpea crops will perform best before they are produced on a mass scale for cattle.

Credit: Canadian Light Source

Dust travelled thousands of miles to enrich hawaiian soils

With its warm weather and sandy beaches, Hawaii is a magnet for tourists every year. This unique ecosystem also attracts soil scientists interested in what surprises may lie beneath their feet.

In a recent paper published in Geoderma, European researchers outline how they used the rich soils of Hawaii to study the critical movement of phosphorous through the environment. By better understanding the amount and type of phosphorus in the soil, they can help crops become more successful and maintain the health of our ecosystems for years to come.

The project was led by Agroscope scientist Dr. Julian Helfenstein, Prof. Emmanuel Frossard with the Institute of Agricultural Sciences, ETH Zurich; and Dr. Christian Vogel, a researcher at the Federal Institute for Materials Research and Testing in Berlin.

The team used the Canadian Light Source (CLS) at the University of Saskatchewan to help analyze the different types of phosphorus in their samples and track their origins.

Read more on the Canadian Light Source website

Image: Dr. Christian Vogel using the VLS-PGM beamline to analyze a sample at the CLS.

Get out your vacuum: Scientists find harmful chemicals in household dust

Since the 1970s, chemicals called brominated flame retardants (BFRs) have been added to a host of consumer and household products, ranging from electronics and mattresses to upholstery and carpets. While they were intended to improve fire safety, one form — polybrominated diphenyl ethers, or PBDEs — has proved harmful to human health, specifically our hormonal systems.

Although the use of PBDEs has been restricted in Canada since 2008, older household electronics and furniture with these compounds are still in use. Additionally, the process used to add this chemical to manufactured goods attached the particles very loosely. As a result, the compound tends to shed over time through normal wear and tear.

A growing body of evidence suggests that concentrations of this chemical are higher indoors and that it is present in dust. A team of researchers from the Canadian Light Source (CLS) at the University of Saskatchewan and Memorial University set out to determine whether they could find bromine in household dust using synchrotron X-ray techniques.

Read more on the Canadian Light Source website

Image: Dr. Peter Blanchard, CLS Associate Scientist, standing in the HXMA beamline at the CLS.

In search of the perfect system

Researchers take a new approach to improve widely used biotechnology tool

The unique relationship between an essential vitamin and a purified bacterial protein has been used as a valuable tool in science and medicine for several decades. Together these two molecules, known as streptavidin and biotin, form a very strong and specific interaction that is invaluable for many biotechnological applications.

Labeling molecules with biotin and detecting them with streptavidin is a common part of many lab tests and has enabled many scientific discoveries in medicine. Streptavidin and biotin are as essential to lab technicians as hammers and nails are to a carpenter. The two molecules combine to form “molecular glue” for many of the tests used to diagnose infectious diseases like HIV, Hepatitis C and Lyme disease, to discover new proteins, viruses and bacteria, and to explore how molecules function in living organisms.

Read more on the Canadian Light Source website

Image: Trapped biotin: A crystal structure of the M88 mutein, determined at the CMCF beamline at CLS, reveals how the engineered disulphide formed between Cys49 and Cys86 (green spheres) partially block the exit pathway for biotin (magenta spheres). Credit: CLS

Powering the future of clean energy

Hydrogen gas can be used to power vehicles and has the potential to provide electricity to homes

The global quest for clean energy is championed by researchers in Canada who are focused on harnessing the potential of hydrogen.

The idea of the hydrogen economy was first proposed 50 years ago as a way to combat the negative effects of fossil fuels. Its future is the focus of new research from the University of Toronto’s Thermofluids for Energy and Advanced Materials (TEAM) lab, whose work relied on the Canadian Light Source (CLS) at the University of Saskatchewan to visualize performance.

Read more on the Canadian Light Source website

Image: Adam Webb (CLS), Sergey Gasilov (CLS), Manojkumar Balakrishnan (U of T), Jason Keonhag Lee (U of T), Denise Miller (CLS), Kieran Fahy (U of T) on the BMIT beamline at CLS.

Protecting Saskatchewan lakes from contamination

Using the Canadian Light Source synchrotron, a University of Saskatchewan-led research team has developed a method for monitoring uranium contaminants in mine tailings using samples from McClean Lake, SK.

While mining companies work to extract as much uranium as possible from processed ore, small amounts remain in the solid and liquid residue—called tailings—left over from the milling process.

To protect the downstream environment from potential impacts of the solid waste, the Canadian Nuclear Safety Commission requires companies to monitor the chemistry of uranium and other potentially harmful elements in their tailings facilities.

Numerous researchers have studied the chemistry of nickel, arsenic, selenium and molybdenum in Orano Canada’s tailings management facility at McClean Lake, but to date little was known about residual uranium. One of the challenges has been the extremely low concentrations of the element left after processing at Orano’s ore mill, which began operating in 1997.

Read more on the Canadian Light Source website

Image: Arthur Situm conducting research at SXRMB beamline. Photo by David Stobbe for USask.

Protecting our food from mercury contamination

One size does not fit all when it comes to using biochar for soil remediation, according to researchers who used the Canadian Light Source (CLS) at the University of Saskatchewan.

Mercury is used in a variety of industries, including textile manufacturing and gold and silver mining. When released into the environment, this highly toxic element causes widespread contamination of soil. As mercury enters rivers, lakes and oceans, it is converted to methylmercury, a neurotoxin that moves into the food chain through fish and seafood, posing a serious risk to human health.

Conventional methods of remediating mercury-contaminated soil – such as adding activated carbon – can be quite expensive to apply on a large scale. However, recent research has found that biochar, a charcoal produced by superheating agriculture or forestry waste in the absence of oxygen, holds promise as a low cost, “green” alternative.

Read more on the Canadian Light Source website

Image: The experimental set-up. Credit: Canadian Light Source

Creating the best TV screen yet

Breakthrough in blue quantum dot technology

There are many things quantum dots could do, but the most obvious place they could change our lives is to make the colours on our TVs and screens more pristine. Research using the Canadian Light Source (CLS) at the University of Saskatchewan is helping to bring this technology closer to our living rooms.

Quantum dots are nanocrystals that glow, a property that scientists have been working with to develop next-generation LEDs. When a quantum dot glows, it creates very pure light in a precise wavelength of red, blue or green. Conventional LEDs, found in our TV screens today, produce white light that is filtered to achieve desired colours, a process that leads to less bright and muddier colours.

Until now, blue-glowing quantum dots, which are crucial for creating a full range of colour, have proved particularly challenging for researchers to develop. However, University of Toronto (U of T) researcher Dr. Yitong Dong and collaborators have made a huge leap in blue quantum dot fluorescence, results they recently published in Nature Nanotechnology.

Read more on the Canadian Light Source website

Image: The blue quantum dot solution glows in a vial in a laboratory.

Longer-lasting cell phone batteries

Studies demonstrate the promise of phosphorene in electronics

Phosphorene is attracting a lot of attention lately in the energy and electronics industries, and for good reason. The theoretical capacity of the two-dimensional material—which consists of a single layer of black phosphorus—is almost seven times that of anode materials currently used in lithium-ion batteries. That could translate into real-world benefits such as significantly greater range for electric vehicles and longer battery life for cell phones.

There are a couple of strikes against phosphorene though. Commercially available black phosphorus is costly, at roughly $1000 per gram, and it breaks down quickly when it’s exposed to air. Researchers from Western University teamed up with scientists from the Canadian Light Source (CLS) at the University of Saskatchewan on a pair of studies to determine if they could address both issues.

Read more on the Canadian Light Source website

Image: Dr. Andy Sun at the Canadian Light Source.

How cellular proteins control cancer spread

New finding may help focus the search for anti-cancer drugs

A new insight into cell signals that control cancer growth and migration could help in the search for effective anti-cancer drugs. A team of researchers has revealed key biochemical processes that advance our understanding of colorectal cancer, the third most common cancer among Canadians.

Using the CMCF beamline at the Canadian Light Source (CLS) at the University of Saskatchewan, scientists from McGill University and Osaka University in Japan were able to unlock the behavior of an enzyme involved in the spread of cancer cells. The team found that there is a delicate interaction between the enzyme, PRL3, and another protein that moves magnesium in and out of cells. This interaction is crucial to colorectal cancer growth.

A new insight into cell signals that control cancer growth and migration could help in the search for effective anti-cancer drugs. A team of researchers has revealed key biochemical processes that advance our understanding of colorectal cancer, the third most common cancer among Canadians.

Using the CMCF beamline at the Canadian Light Source (CLS) at the University of Saskatchewan, scientists from McGill University and Osaka University in Japan were able to unlock the behavior of an enzyme involved in the spread of cancer cells. The team found that there is a delicate interaction between the enzyme, PRL3, and another protein that moves magnesium in and out of cells. This interaction is crucial to colorectal cancer growth.

Read more on the Canadian Light Source website

Image: Members of the Gehring research laboratory discussing the results of a protein purification.

Conserving Rita Letendre’s famous artworks

Research undertaken at the Canadian Light Source (CLS) at the University of Saskatchewan was key to understanding how to conserve experimental oil paintings by Rita Letendre, one of Canada’s most respected living abstract artists.

The work done at the CLS was part of a collaborative research project between the Art Gallery of Ontario (AGO) and the Canadian Conservation Institute (CCI) that came out of a recent retrospective Rita Letendre: Fire & Light at the AGO. During close examination, Meaghan Monaghan, paintings conservator from the Michael and Sonja Koerner Centre for Conservation, observed that several of Letendre’s oil paintings from the fifties and sixties had suffered significant degradation, most prominently, uneven gloss and patchiness, snowy crystalline structures coating the surface known as efflorescence, and cracking and lifting of the paint in several areas.

Read more on the Canadian Light Source website

Image: Rita Letendre. Victoire [Victory], 1961. Oil on canvas, Overall: 202.6 × 268 cm. Art Gallery of Ontario. Gift of Jessie and Percy Waxer, 1974, donated by the Ontario Heritage Foundation, 1988. © Rita Letendre L74.8.