The study, published today by The Lancet in the journal EClinicalMedicine, was commissioned by the World Health Organization (WHO) as part of a planned update to its guidelines for HIV antiretroviral treatment (ART). The study found that dolutegravir is the optimal medication for first-line treatment for people newly diagnosed with HIV, a choice that has not been clear over the past several years.

“Research supporting the 2016 WHO guidelines suggested that dolutegravir was effective and well tolerated, but its efficacy and safety among key populations, such as pregnant women and people living with both HIV and tuberculosis (TB), remained unclear,” said the study’s lead author, Dr. Steve Kanters, who completed the research as a PhD candidate in UBC’s School of Population and Public Health (SPPH). “In 2018, new research warned of a potentially serious increase in risk of neural tube defects in the children of women who became pregnant while taking this treatment.”

The risk of adverse reaction meant that, although dolutegravir was found to be favourable compared to other options, it was only recommended as an alternative, with an antiretroviral called efavirenz recommended as the primary treatment.

The study team, which included Dr. Nick Bansback, associate professor at SPPH, Dr. Aslam Anis, professor at SPPH and director of the Centre for Health Evaluation and Outcome Sciences (CHÉOS), and Dr. Ehsan Karim, assistant professor at SPPH, completed a network meta-analysis of research stemming from 68 available antiretroviral therapy (ART) clinical trials.

They found dolutegravir was superior to efavirenz in most outcomes, including viral suppression, tolerability, and safety. According to Kanters, the increased odds of viral suppression with dolutegravir could have a significant impact on achieving international goals for HIV treatment.

“We found about a five per cent increase in the probability of viral suppression, which means that more people who start treatment will be able to successfully control their HIV,” he said.

Another key attribute of dolutegravir is that it is effective in people who are resistant to NNRTI-class antiretrovirals, like efavirenz, a problem that is becoming increasingly common.

The analysis also showed that dolutegravir and efavirenz had similar rates of adverse events for pregnant women — the increased risk of neural tube defects for dolutegravir was estimated to be less than 0.3 per cent.

“The new evidence on neural tube defects show that the risk with dolutegravir is much more tolerable than previously thought and should quell the initial worry about this drug,” said Kanters.

“Dolutegravir appears to be here to stay as the preferred treatment for people newly diagnosed with HIV,” he said. “However, it is important to recognize the good that efavirenz has done over the past two decades, as it helped lead the ART scale-up around the world.”

Despite the many benefits of dolutegravir, dolutegravir use was associated with increased weight gain, a side effect that could increase the risk of aging-associated comorbidities, like heart attack or stroke.

“In many places, well-treated HIV has become a chronic condition and we are now seeing people living long lives with HIV,” said Kanters. “The research community will continue to monitor the effects dolutegravir may have on the healthy aging process.”

While this study is specifically focused on the optimal treatment for people newly diagnosed with HIV, an upcoming publication will review the evidence in support of switching to dolutegravir for people whose first treatment choice has been unsuccessful in controlling their infection. This recommendation could mean improved treatment for the many people living with HIV around the world who are unable to achieve viral suppression despite being on treatment.

Rising CO₂ levels helped end the last ice age, but the cause of this CO₂ rise has puzzled scientists for decades. Using geochemical fingerprinting of fossil corals, an international team of scientists has found new evidence that this CO₂ rise was linked to extremely rapid changes in ocean circulation around Antarctica.

The team collected fossil remains of deep-sea corals that lived thousands of metres beneath the waves. By studying the radioactive decay of the tiny amounts of uranium found in these skeletons, they identified corals that grew at the end of the ice age around 15,000 years ago.

Further geochemical fingerprinting of these specimens — including measurements of radiocarbon — allowed the team to reconstruct changes in ocean circulation and compare them to changes in global climate at an unprecedented time resolution.

Professor Laura Robinson, Professor of Geochemistry at Bristol’s School of Earth Sciences who led the research team, said: “The data show that deep ocean circulation can change surprisingly rapidly, and that this can rapidly release CO₂ to the atmosphere.”

Dr James Rae at St Andrew’s School of Earth and Environmental Sciences, added: “The corals act as a time machine, allowing us to see changes in ocean circulation that happened thousands of years ago.

“They show that the ocean round Antarctica can suddenly switch its circulation to deliver burps of CO₂ to the atmosphere.”

Scientists have suspected that the Southern Ocean played an important role in ending the last ice age and the team’s findings add weight to this idea.

Dr Tao Li of Nanjing University, lead author of the new study, said: “There is no doubt that Southern Ocean processes must have played a critical role in these rapid climate shifts and the fossil corals provide the only possible way to examine Southern Ocean processes on these timescales.”

In another study published in Nature Geoscience this week the same team ruled out recent speculation that the global increase in CO₂ at the end of the ice age may have been related to release of geological carbon from deep sea sediments.

Andrea Burke at St Andrew’s School of Earth and Environmental Sciences, added: “There have been some suggestions that reservoirs of carbon deep in marine mud might bubble up and add CO₂ to the ocean and the atmosphere, but we found no evidence of this in our coral samples.”

Dr Tianyu Chen of Nanjing University said: “Our robust reconstructions of radiocarbon at intermediate depths yields powerful constraints on mixing between the deep and upper ocean, which is important for modelling changes in circulation and carbon cycle during the last ice age termination.

Dr James Rae added: “Although the rise in CO₂ at the end of the ice age was dramatic in geological terms, the recent rise in CO₂ due to human activity is much bigger and faster. What the climate system will do in response is pretty scary.”

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The membranes themselves, made of anodized aluminum oxide, have a honeycomb-like structure made up of hexagonal openings that allow gas molecules to flow in and out when in the open state. However, gas passage can be blocked when a thin layer of metal is electrically deposited to cover the pores of the membrane. The work is described in the journal Science Advances, in a paper by Professor T. Alan Hatton, postdoc Yayuan Liu, and four others.

This new “gas gating” mechanism could be applied to the continuous removal of carbon dioxide from a range of industrial exhaust streams and from ambient air, the team says. They have built a proof-of-concept device to show this process in action.

The device uses a redox-active carbon-absorbing material, sandwiched between two switchable gas gating membranes. The sorbent and the gating membranes are in close contact with each other and are immersed in an organic electrolyte to provide a medium for zinc ions to shuttle back and forth. These two gating membranes can be opened or closed electrically by switching the polarity of a voltage between them, causing ions of zinc to shuttle from one side to the other. The ions simultaneously block one side, by forming a metallic film over it, while opening the other, by dissolving its film away.

When the sorbent layer is open to the side where the waste gases are flowing by, the material readily soaks up carbon dioxide until it reaches its capacity. The voltage can then be switched to block off the feed side and open up the other side, where a concentrated stream of nearly pure carbon dioxide is released.

By building a system with alternating sections of membrane that operate in opposite phases, the system would allow for continuous operation in a setting such as an industrial scrubber. At any one time, half of the sections would be absorbing the gas while the other half would be releasing it.

“That means that you have a feed stream coming into the system at one end and the product stream leaving from the other in an ostensibly continuous operation,” Hatton says. “This approach avoids many process issues” that would be involved in a traditional multicolumn system, in which adsorption beds alternately need to be shut down, purged, and then regenerated, before being exposed again to the feed gas to begin the next adsorption cycle. In the new system, the purging steps are not required, and the steps all occur cleanly within the unit itself.

The researchers’ key innovation was using electroplating as a way to open and close the pores in a material. Along the way the team had tried a variety of other approaches to reversibly close pores in a membrane material, such as using tiny magnetic spheres that could be positioned to block funnel-shaped openings, but these other methods didn’t prove to be efficient enough. Metal thin films can be particularly effective as gas barriers, and the ultrathin layer used in the new system requires a minimal amount of the zinc material, which is abundant and inexpensive.

“It makes a very uniform coating layer with a minimum amount of materials,” Liu says. One significant advantage of the electroplating method is that once the condition is changed, whether in the open or closed position, it requires no energy input to maintain that state. Energy is only required to switch back again.

Potentially, such a system could make an important contribution toward limiting emissions of greenhouse gases into the atmosphere, and even direct-air capture of carbon dioxide that has already been emitted.

While the team’s initial focus was on the challenge of separating carbon dioxide from a stream of gases, the system could actually be adapted to a wide variety of chemical separation and purification processes, Hatton says.

“We’re pretty excited about the gating mechanism. I think we can use it in a variety of applications, in different configurations,” he says. “Maybe in microfluidic devices, or maybe we could use it to control the gas composition for a chemical reaction. There are many different possibilities.”

Pete Goldsmith, director of the Soybean Innovation Lab at University of Illinois, works closely with partner organizations in several African countries. He noticed that his African colleagues were often dealing with technological problems that made communication very challenging. For example, sometimes they had to rely on their cell phones because their institution’s internet access was unreliable.

Goldsmith teamed up with two IT experts at U of I, former Chief Information Officer Paul Hixson and Director of Research IT and Innovation Tracy Smith, to investigate technological challenges facing institutions in developing countries.

“Connectivity is the oxygen organizations run on,” Hixson says. “It’s such a basic requirement that it’s often not even recognized as an issue. But lack of connectivity severely hinders an organization’s ability to perform simple functions, conduct research, and compete for grants.”

Goldsmith, Hixson, and Smith conducted an in-depth case study of information communication technology (ICT) infrastructure at the Savannah Agricultural Research Institute (SARI), a leading research station in Ghana and a close collaborator of SIL.

The case study included focus groups, interviews, and a technological analysis of SARI’s equipment and connectivity. Based on this study, the research team developed the ICT Health Checkup, an assessment procedure for IT administrators to methodically assess the current state of their system, identify gaps affecting performance, and document steps for remediation.

The ICT Health Checkup tool systematically evaluates four key elements of ICT infrastructure. The first step focuses on connectivity and bandwidth, identifying the required bandwidth to accommodate the institution’s needs and whether the institution has an uninterrupted fiber-based connection to the global internet. The second step analyzes core physical infrastructure, including dependable electricity, local network design, and both wired and wireless connectivity capabilities.

The third step looks at available intranet service offerings for researchers such as local storage, data backup procedures, access control, security procedures, email service, and cloud access. Finally, the fourth step deals with the human resources and technical support requirements for planning and managing the institution’s IT infrastructure.

“With this tool, institutions can go through a checklist, and at each point there is a ‘stoplight’. If it’s red, you know there is something that needs to be fixed, because there are conditions that will act as a block and you can’t go on until they are fixed — until there’s a green light. So turning things from red to green at each step is crucial; methodically going through each step at a time and making sure it’s fixed before moving on to the next one,” Hixson explains.

The researchers compare the ICT Health Checkup to a medical health exam; it measures the current conditions and can be used as a benchmarking tool to measure improvements.

Goldsmith says the tool can be used to empower organizations so they can be self-sufficient. “With proper connectivity you can manage and store research data, compete for grants, and manage awards,” he notes. “It’s the foundation that allows institutions to participate fully in a global context.”

The research team is currently expanding the study, collecting data from nine institutions and five networking organizations operating in three countries, in order to create a more robust picture of internet connectivity challenges and potential solutions across Africa.

They are also collaborating with the National Research and Education Networks (NRENs) in each of the sub-Saharan African countries that SIL operates in. These African NRENs are comparable to Internet², which has been an instrumental partner in the expansion and adoption of advanced computing technologies at U of I and is one of the leading NRENs in the U.S., serving the country’s research and higher-education communities.

“With the ICT health checkup, our partner African NRENs now have an actual assessment tool they can use with their member institutions. It’s becoming a continent-wide approach as they are starting to adopt this new instrument created at the U of I to be their benchmark and measurement tool,” Goldsmith says.

“The U of I is ideally positioned to provide this knowledge, because of the university’s continued leadership in the computational and network administration space,” he adds. “Now we are extending that to have real impact overseas.”