Saturday, March 16, 2024

 

New data show severe racial and ethnic inequities in child opportunity in and between US Metros


Brandeis University’s Child Opportunity Index 3.0 reveals connections between race/ethnicity, neighborhood opportunity, and life outcomes for children



BURNESS





Waltham, MA. (March 14, 2024) – Children of different races and ethnicities, even living in the same metro area a few miles apart, are often growing up in neighborhoods with radically different opportunities to thrive, according to a new index of neighborhood features that compares data on all 73,000 census tracts in the country. The project, the Child Opportunity Index (COI) 3.0, analyzes measures of opportunity across three domains: education, health and environment and social and economic, and ranks neighborhoods by a Child Opportunity Score ranging from 1-100. An accompanying report finds that in the nation’s 100 largest metro areas, children face significant inequities in opportunity. The typical White child lives in a neighborhood with an opportunity score of 74 out of 100, whereas that score is 30 for Black children, and 33 for Hispanic children. The Index is being released today by the diversitydatakids.org project at Brandeis University. 

The data included in the report shed light on two related challenges:  

Metro areas can either share or hoard opportunity. 

For instance, Detroit, Michigan, and Fayetteville, Arkansas, have just about the same overall opportunity score: 57 and 56, respectively. But they have dramatically different inequities in the opportunity that typical children may experience: an 88-point gap between high- and low-opportunity neighborhoods in Detroit, compared to a 59-point gap in Fayetteville. In short, Fayetteville shares opportunity, whereas Detroit tends to hoard opportunity in select neighborhoods. 

Metro areas can either support or hinder equitable access to opportunity by race and ethnicity. 

In the 100 largest metro areas, Black and Hispanic children almost universally live in lower opportunity neighborhoods than White and Asian children. But some inequities are much larger than others. In Milwaukee, Wisconsin, there is a 74-point gap between the Opportunity Score that a typical White and Black child experiences and a 59-point gap between the typical White and Hispanic child. But in Madison, Wisconsin, there is only an 8-point gap between the neighborhoods of typical White and Black children, and a 9-point gap for White and Hispanic children.   

“The data show us that the U.S. can provide children with rich opportunities to learn and grow, but that we’re not doing so equitably,” says diversitydatakids.org Director Dr. Dolores Acevedo-Garcia, who is a professor at the Heller School for Social Policy and Management, Brandeis University. “These inequities, between high- and low-opportunity neighborhoods, and between children of different racial and ethnic groups, are neither natural nor random. They’re driven by systemic inequities such as high segregation and policies that enable opportunity hoarding. But we can close these inequities. The Child Opportunity Index points us to where we need to do more to improve opportunity for the highest-need children.” 

Child Opportunity Impacts Life Expectancy 

For a child, growing up in a neighborhood with low opportunity hurts them today and into their future. The researchers find that in the 100 largest metro areas, the difference in life expectancy for children who live in very high- versus very low-opportunity neighborhoods is 6 years — a difference of living to 82 years old versus only 76. In some metros, like Dayton, Ohio, that difference in life expectancy is as large as 10 years. Health conditions like obesity and diabetes in adulthood are strongly correlated with neighborhood opportunity during childhood, too. 

The Child Opportunity Index is a composite of 44 indicators spanning three domains. Since its inception in 2014, the COI has included measures such as school quality, access to green space and the poverty rate. For the COI 3.0 being released today, new indicators include neighborhood broadband access, and neighborhood density of nonprofit organizations, as well as improved measures of school quality and access to green space. 

“These 44 indicators reflect key neighborhood features that influence healthy child development,” says Dr. Clemens Noelke, Research Director for the Child Opportunity Index and Senior Research Scientist at Brandeis. “When combined into a single index, they illustrate the intersecting and compounding causeways through which neighborhoods shape children’s health and experiences.” 

Over the last several years, state and local leaders across the country have applied the COI for positive change. For example, Massachusetts’ Executive Office of Housing and Livable Communities helps families eligible for Housing Choice Vouchers relocate to designated “opportunity areas,” as defined by the COI. Since 2019, 125 families, including 270 children, have moved from lower-opportunity to higher-opportunity neighborhoods. An evaluation of the program shows that the families have experienced improved physical and mental health, educational opportunities, and access to green space in their new neighborhoods. Nearly all participants described their new neighborhood as inclusive and welcoming, and 88% report no drawbacks for themselves or their children. 

“The Child Opportunity Index is an invaluable source of actionable neighborhood data to identify, understand, and confront structural barriers to health,” said Alonzo Plough, Chief Science Officer and Vice President, Research-Evaluation-Learning, at the Robert Wood Johnson Foundation, one of the funders of the Child Opportunity Index. “We hope that community leaders can use these data to build on their own expertise and identify ways to remove these barriers and support equitable opportunity for all children.” 

The Child Opportunity Index is an essential tool for every community looking to make children’s lives better,” said Icela Pelayo, Program Officer, Racial Equity & Community Engagement at the W.K. Kellogg Foundation. “Communities sharing their stories, coupled with this data from the Child Opportunity Index, illustrates how past policies and decisions impact us today, and more importantly, offers steps we can take together to ensure children, families and our communities thrive.”   

Recommendations for Policymakers 

The creators of the COI 3.0 offer recommendations for policymakers at the federal, state, and local levels to improve equitable access to neighborhood opportunity. Examples include:  

  • Reduce child poverty via expansions to programs like the Child Tax Credit (CTC). The 2021 expanded CTC reduced child poverty to a historic low and showed how certain elements (like eliminating minimum family income requirements) can improve racial/ethnic equity. As children in poverty tend to live in segregated neighborhoods, reducing child poverty will also reduce concentrated neighborhood poverty and benefit large numbers of Black, Hispanic and Native American children in low-opportunity neighborhoods.  

  • Increase families’ ability to access higher opportunity neighborhoods via zoning reform. Examples of restrictive zoning include regulations that limit multifamily housing or require a large lot size for new housing construction. These restrictions tend to hurt low-income families’ ability to access the schools, parks, community safety and other qualities that high-opportunity neighborhoods offer. These restrictions also have disproportionate negative effects on racial/ethnic minority families. Exclusionary zoning not only perpetuates segregation and opportunity hoarding; it can also be economically inefficient and environmentally damaging. 

  • Increase children’s access to quality schools via school assignment reform. Most school assignments are based on the neighborhoods where children live. School choice initiatives and school integration programs give families the ability to pick a school outside of their immediate neighborhood, allowing students who live in low-opportunity neighborhoods to attend schools with more experienced teachers and better educational outcomes.  

Of the 100 largest metro areas in the country, the three with the highest overall Opportunity Scores are: Bridgeport, Conn. (88), San Jose, Calif. (87) and Boston, Mass. (86). The three with the lowest overall scores are: McAllen, Texas (6), Brownsville, Texas (9) and Visalia, Calif. (13).  

The metro areas with the widest gaps between very high- and very low-opportunity neighborhoods are Milwaukee, Wis. (90), Cleveland, Ohio (88) and Detroit, Mich. (88). The three with the smallest gaps are Provo, Utah (32), Brownsville, Texas (34) and McAllen, Texas (34).  

The metro areas with the widest gaps between White and Black children are: Milwaukee (74), Cleveland (62) and Los Angeles (61); and between White and Hispanic children are Los Angeles (59), Milwaukee (59) and Hartford, Conn. (55).  

# # # 

About diversitydatakids 

diversitydatakids.org is a comprehensive research program to monitor the state of wellbeing, diversity, opportunity and equity among U.S. children. Established in 2014, diversitydatakids.org fills an urgent need for a rigorous, equity-focused research program with a clear mission to help improve child wellbeing and increase racial and ethnic equity in opportunities for children. diversitydatakids.org is housed at the Institute for Child, Youth and Family Policy at the Heller School for Social Policy and Management at Brandeis University and funded by the W.K. Kellogg Foundation and the Robert Wood Johnson Foundation.  

 

ESHRE launches factsheets to highlight environmental threats to fertility and reproductive health



EUROPEAN SOCIETY OF HUMAN REPRODUCTION AND EMBRYOLOGY





Governments must act now to address the effects of climate change and air pollution on fertility rates and reproductive health, says a document published by the European Society of Human Reproduction and Embryology (ESHRE) today (Thursday).

The factsheets* provide comprehensive information on global warming, evidence of its impact on fertility, and calls on policymakers to promote swift prevention measures.

Priorities should be to reach net zero CO2 emissions within the next 20 years, and to keep global warming within a 1.5% increase, says the expert panel that developed the factsheets.

Countries are also urged to support research into the effects of air pollution and heat exposure on fertility and pregnancy. The ESHRE document says any new evidence could then help guide policies to protect populations.

Air pollution and extreme heat are strongly linked with compromised fertility such as lower sperm counts, reduced pregnancy rates, and an increased risk of miscarriage, says the evidence-based document.

Key data outlined in the factsheet includes:

  • Living within 200 metres of a major road is linked to a higher risk of self-reported infertility. Pregnancy rates increase by 3% for every 200 metres between a residence and a major road.
  • A total of 2.7m (18%) of pre-term births worldwide could be attributed to pollution from fine particulate matter.  
  • Exposure to wildfires has been linked to a risk of low birth weight.
  • Pregnant women who are exposed to extreme heat are at higher risk of pre-term birth, low birth weight babies, and stillbirth.
  • Mothers exposed to heat during delivery are more likely to experience hypertension, poorer pregnancy outcomes, and longer hospital stays.
  • Up to around 3.6 billion people live in areas deemed “highly vulnerable” to climate change.

The document is based on recommendations** published by ESHRE last year to highlight the growing threat from climate change, pollutants, hormone-disrupting chemicals, toxic substances, and other related risks.

Professor Willem Ombelet, who helped produce the factsheet, said: “As this document shows, there is increasing evidence to link environmental factors with declining fertility rates and adverse pregnancy outcomes. 

EU members are among countries that have taken action to address this concerning issue. But too often male and female fertility is not seen as a priority and more measures are needed to tackle the impact of climate change.

Swift action is needed not only to protect this generation but also the health and fertility of future generations.”

 

Researchers can reveal illegal timber exports


Peer-Reviewed Publication

UNIVERSITY OF GOTHENBURG

Timber 

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TIMBER SOLD WITH FALSE DESIGNATION OF ORIGIN IS A GLOBAL PROBLEM. BY ANALYSING ISOTOPE RATIOS AND TRACE ELEMENTS IN THE WOOD, RESEARCHERS CAN DEDUCE WHERE THE TIMBER WAS HARVESTED.

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CREDIT: JOHAN WINGBORG




A new method of timber analysis developed by researchers from the University of Gothenburg can confidently identify the location in which the tree was harvested. The method has been developed with the aim of combating illegal timber imports from Russia and Belarus.

Illegal logging and the associated trade in wood products is a global problem that threatens some of the world's most important ecosystems. Researchers are trying to combat this practise with a new scientific method that can reveal where a tree has been harvested. The researchers present their findings in a paper published in the journal Nature Plants.

“The issue became even more urgent after Russia's full-scale invasion of Ukraine in February 2022. Russian timber continues to be exported to the EU and the US despite imposed sanctions, by falsifying the origin of the timber. Illegal timber exports are partly financing Russia's war,” says Jakub Truszkowski, researcher in computational biology at the University of Gothenburg.

Chemical footprint

A growing tree is affected by its environment. Soil composition, environmental pollution and climate leave a chemical footprint in wood tissue, and this is what the researchers use to determine its origin. First, a large collection of reference material is required. Then, using machine learning, the researchers can determine whether the stated harvest location of the sample is correct.

“We collected 900 wood samples from 11 Eastern European countries, including Belarus and Russia. We selected oak, birch, pine and beech, all of which are important in the timber trade. By analysing and comparing isotope ratios and the concentrations of 15 different trace elements in wood tissue, we can determine the harvest location of the tree within a 200 kilometer radius,” says Jakub Truszkowski.

Useful worldwide

The study led to the creation of a comprehensive reference database on Eastern European timber, tailored to products under sanctions after the invasion of Ukraine. These data facilitated the development of methods to verify the authenticity of timber origin claims and even predict the location of harvest.

“We would like to refine our method so that we can further increase the accuracy and confidence in our predictions. It is still under development and will get better the more data we get,” says Jakub Truszkowski.

While this study focused on the illegal timber trade in Eastern Europe, the method is applicable all over the world. It is estimated that more than half of tropical timber may be harvested illegally.

“It is important to protect highly biodiverse forests from illegal logging. By tracing the origin of timber, we can combat this practice,” says Jakub Truszkowski.

Scientific article in Nature Plants: A framework for tracing timber following the Ukraine invasion


By analysing isotope ratios and trace elements in the wood, researchers can deduce where the timber was harvested.

CREDIT

Jakub Truszkowski

 

Dolphin-kick swimming maximizes water-flow utilization with increasing speed


Peer-Reviewed Publication

UNIVERSITY OF TSUKUBA





Tsukuba, Japan—The swimming motion imparts momentum to water, a fluid, thereby generating a propulsive force. Thus, we can understand the propulsion mechanism by examining the water flow generated by a swimmer's motion. However, observing colorless, transparent water with the naked eye or a camera is challenging. To address this issue, researchers employed particle image velocimetry, a technique utilized in fluid dynamics, to visualize water-flow patterns. They investigated how water flow changes as swimmers change their speed while executing the dolphin-kick swimming technique. This investigation was conducted in an experimental circulating-water channel (a pool with flowing water).

The results revealed that the water-flow velocity increased with increasing swimming speed during the underwater dolphin-kick lower-limb action, generating a strong vortex during the kicking action. This phenomenon possibly contributes to the increased propulsive force. Additionally, recycling of the flow generated during the downward-kick phase was observed during the transition to the upward-kick phase, with the effect becoming more pronounced as the swimming speed increased. This study marks the first observation of water-flow changes during dolphin-kick swimming at varying speeds.

This study is expected to advance research on water flow, a critical topic in swimming research. It offers scientific evidence for instructors to adopt kick-swimming techniques.

###
This work was supported by Japan Science and Technology Agency, Grant Number 22 K19725.

 

Original Paper

Title of original paper:
Impact of variations in swimming velocity on wake flow dynamics in human underwater undulatory swimming

Journal:
Journal of Biomechanics

DOI:
10.1016/j.jbiomech.2024.112020

Related Link

Institute of Health and Sport Sciences

Advanced Research Initiative for Human High Performance (ARIHHP)

SMART and NTU Singapore researchers develop method to measure carbon stored in bogs, aiding peatland restoration efforts




SINGAPORE-MIT ALLIANCE FOR RESEARCH AND TECHNOLOGY (SMART)

The mounded shape of a raised bog (Valgeraba, Estonia) is revealed by a coloured relief map overlaid on aerial photography based on lidar data from the Estonian Land Board. Elevations are exaggerated to emphasise its mounded shape. 

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THE MOUNDED SHAPE OF A RAISED BOG (VALGERABA, ESTONIA) IS REVEALED BY A COLOURED RELIEF MAP OVERLAID ON AERIAL PHOTOGRAPHY BASED ON LIDAR DATA FROM THE ESTONIAN LAND BOARD. ELEVATIONS ARE EXAGGERATED TO EMPHASISE ITS MOUNDED SHAPE.

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CREDIT: SINGAPORE-MIT ALLIANCE FOR RESEARCH AND TECHNOLOGY (SMART)




Researchers at Singapore-MIT Alliance for Research and Technology (SMART), MIT’s research enterprise in Singapore, and Nanyang Technological University, Singapore (NTU Singapore), have developed a method that can accurately measure the amount of carbon stored in bogs.

The new method by the SMART-NTU team uses satellite data and reduces the need for on-site sampling to derive the three-dimensional shapes of raised peatlands, also known as bogs, and hence the amount of carbon it contains. The new mathematical model replaces earlier models whose accuracy is limited to specific bog conditions and was developed with collaborators from the Massachusetts Institute of Technology, University of Potsdam, Stanford University and the University of Minnesota.

Measuring carbon stocks in raised peatlands is challenging. The variable shape of bogs and varying depths of their carbon-rich soil known as peat, combined with their inaccessibility and vast size in many tropical regions, makes obtaining accurate data difficult, say the team of researchers.

Measuring the amount of carbon stored in peatlands helps governments and policymakers assess the environmental impact of converting these lands for agricultural, industrial or urban uses, particularly by understanding potential carbon emissions resulting from peatland drainage.

Globally, the drainage of peatlands for agricultural use releases large amounts of carbon dioxide and increases the risk of catastrophic fires. Dry peat is highly flammable and can easily catch fire, especially in regions with hot climates and dry seasons, such as Southeast Asia - where haze is a recurrent pollution issue. Southeast Asia is home to about 23 million hectares of peatlands, about half of the world’s tropical peatlands.

Although bogs represent only three per cent of the world’s land surface, they store the most carbon per area of any land ecosystem on Earth. Understanding bogs is crucial to protect and restore their large carbon stocks. Restoring bogs through a method known as rewetting is one of the most promising nature-based solutions to fight climate change.

First author Dr Alex Cobb, Senior Principal Research Scientist, Singapore-MIT Alliance for Research and Technology, said: “Peatlands have acted as huge stores of carbon since before the time of the dinosaurs. In fact, modern coal deposits started as peatlands. Our mathematical model makes it possible to describe and compare the shape of bogs anywhere, including areas in remote parts of the Amazon Basin, New Guinea, and the Congo Basin that are under threat by development but are still poorly known scientifically. Our finding also has practical applications: the three-dimensional shape of a bog determines the carbon it holds and how it can best be restored. By protecting and restoring peatlands, we can stop the vast greenhouse gas and smoke emissions from drained peatlands, making global climate goals achievable.”

Second author Dr René Dommain, Senior Research Fellow at NTU’s Earth Observatory of Singapore, said: “We can now accurately measure the amount of carbon stored in peatlands that could potentially be released due to environmental change caused by human activities, helping countries with large peatland areas in both reporting and protecting their carbon stocks. We can also determine peatland areas at risk of fire due to changes to their morphology from artificial drainage and contribute towards alleviating the recurring threats of haze that plague Singapore and the region. This work is also a foundation for successful restoration of damaged peatlands.” Dr Dommain was also researcher at NTU’s The Asian School of the Environment when he co-led the study.

The findings from the study titled “A unified explanation for the morphology of raised peatlands" were published in the top peer-reviewed scientific journal Nature on January 4th.

This research involved analysis using detailed measurements of the earth's surface by airplane-mounted lasers at eight sites around the world, including bogs from Quebec (Canada), Alaska, Minnesota and Maine (USA), Finland, Estonia, Brunei Darussalam and New Zealand – building on the theoretical findings from a paper published by SMART in 2017 on the ecological and hydrological processes that control the buildup of carbon in tropical peatlands.

The study was carried out by SMART and supported by the National Research Foundation (NRF) Singapore under its Campus for Research Excellence And Technological Enterprise (CREATE) programme.

Scaling up measurements in peatlands

The scientists can now apply their new method to any bog in the world, which allows them to measure the amount of carbon contained in a bog and mark out areas that could be restored if a bog is already damaged. They checked the validity of deriving the shape of bogs from their model with independently derived Light Detection and Ranging (LIDAR) technology (see Figure 1).

With this new method, the researchers can also determine which parts of the bogs are wet and intact or dry and damaged, pointing to where restoration efforts should be focused.

Restoring peatlands by rewetting reduces greenhouse gas emissions and the occurrence of fires. Peatland becomes wet again by blocking drainage channels, like ditches created for agricultural use and preventing water from draining away. This helps keep carbon stored in the peat, preventing its release into the atmosphere. Rewetting is crucial for reducing greenhouse gas emissions and maintaining the health of peatland ecosystems.

Restoring bogs is also beneficial for biodiversity, as by restoring the natural waterlogged conditions, various plant and animal species adapted to wet environments could thrive.

Last year, SMART researchers published a paper demonstrating the precise measurement of the surface of peatlands by lasers on satellites and the International Space Station. By combining these measurements with the model from this study, researchers can describe bogs’ shapes and carbon stocks worldwide using simple elevation measurements.

Satellites can perform these measurements without the need for labour-intensive ground-based sampling. This finding expands the understanding of global peatlands and provides a foundation for planning natural climate solutions through global restoration or protection of damaged bogs. It also opens up new opportunities for research and commercial applications linked to compliance and voluntary carbon trading markets.

Dr Cobb added: “Drainage of peatlands by people now causes the emission of over a thousand of millions of tonnes of CO2 each year and enables catastrophic fires that have caused hundreds of thousands of premature deaths. Rewetting peatlands could stop these emissions and fires, but it cannot be planned effectively without knowing the subtle gradients in peatland shape that drive the flow of water. By estimating the shape of raised peatlands from limited data, our theory makes it possible to plan peatland rewetting more easily and cost-efficiently than has ever been possible.”

Dr Dommain added: “We developed the first comprehensive theory that explains the morphology of raised bogs globally, essentially solving the problem that peatland scientists struggled with for over 120 years. Ours is a highly relevant contribution because peatlands are dense stores of pure carbon and play a vital role in climate change mitigation strategies.”

The global team of researchers will expand their analyses to remote peatland regions of the tropics for which few data are available. They will develop tools to estimate carbon stocks with this new method to support governmental agencies and the private sector in reducing greenhouse gas emissions from degraded peatlands.

 

New multimillion dollar research facility set to unlock secrets of quantum materials


Material scientists from the University of British Columbia Stewart Blusson Quantum Matter Institute (Blusson QMI) will lead the development of a multi-million world-class crystal growth facility thanks to $5.8 million in new investments


UNIVERSITY OF BRITISH COLUMBIA

Material scientists from the University of British Columbia Stewart Blusson Quantum Matter Institute led by Alannah Hallas (Pictured) and Doug Bonn will lead the development of a multi-million world-class crystal growth facility. 

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MATERIAL SCIENTISTS FROM THE UNIVERSITY OF BRITISH COLUMBIA STEWART BLUSSON QUANTUM MATTER INSTITUTE (BLUSSON QMI) WILL LEAD THE DEVELOPMENT OF A MULTI-MILLION WORLD-CLASS CRYSTAL GROWTH FACILITY THANKS TO $5.8 MILLION IN NEW INVESTMENTS.

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CREDIT: UNIVERSITY OF BRITISH COLUMBIA





Material scientists from the University of British Columbia Stewart Blusson Quantum Matter Institute (Blusson QMI) will lead the development of a multi-million world-class crystal growth facility thanks to $5.8 million in investments by the Canada Foundation for Innovation (CFI) and the B.C. Knowledge Development Fund (BCKDF) announced today.

Blusson QMI Scientific Director Andrea Damascelli said the investment will strengthen Canada’s position as a leader in quantum research and technology.

“The investment enables the establishment of state-of-the-art research infrastructure that is unique in Canada and will deliver exceptional impact for quantum material design, technology development, and training of the quantum workforce,” said Damascelli.

Led by Blusson QMI Investigators Alannah Hallas and Doug Bonnthe new facility represents a total investment of $7.3 million-dollars, and will incorporate specialized apparatus designed for high-pressure synthesis.

“Just as the silicon age launched multiple trillion-dollar industries, the age of quantum materials is likely to foster intense economic development,” said Alannah Hallas.

“The new facility will accelerate this search by enabling us to synthesize quantum materials that have remained out of reach in the high-quality single crystal form that is needed to characterize them and ultimately fashion them into technological devices.”

To tune the formation and structure of new materials, scientists typically use methods that involve varying the temperature or the material’s chemical composition but can rarely significantly increase the pressure.

“Adding pressure as a third tuning parameter during synthesis will vastly expand the frontier across which we can discover novel quantum materials. At elevated pressures, materials can often form into new stable phases that are not accessible at lower pressures,” Hallas said. “A good example of this are diamonds that are formed as a result of squeezing carbon under extreme pressure and high heat.”

The new facility complements the characterization tools and theoretical expertise that already exist at UBC’s Blusson QMI, unlocking an end-to-end scientific workflow from the design and synthesis of new quantum materials to the elucidation of their properties and engineering prototype devices.

Under the direction of Hallas and Bonn, the lab incorporates five new material synthesis furnaces that will position researchers at UBC Blusson QMI and Canada at the forefront of realizing the technological promises of quantum materials.

Three of the five furnaces in the facility will be the first of their kind in the country, including Canada’s first high pressure floating zone furnace. Another high pressure furnace in the facility, known as an anvil press, will be, for the first time, dedicated to quantum materials discovery rather than geoscience.

The CFI Innovation Fund provides continued investments in infrastructure across the full spectrum of research, from the most fundamental to applied through to technology development. By investing in research infrastructure projects through the BCKDF, the B.C. government is continuing to support post-secondary institutions by improving productivity and competitiveness, and to move toward an innovative, sustainable and inclusive future.

Projects funded through the Innovation Fund and the BCKDF will help Canada and British Columbia remain at the forefront of exploration and knowledge generation while making meaningful contributions to generating social, health, environmental and economic benefits and addressing global challenges.

A new ion trap for larger quantum computers



ETH ZURICH

The experimental setup of the ETH researchers. The trap chip is located inside the container underneath the silver cupola, in which a lens captures the light emitted by the trapped ions. 

IMAGE: 

THE EXPERIMENTAL SETUP OF THE ETH RESEARCHERS. THE TRAP CHIP IS LOCATED INSIDE THE CONTAINER UNDERNEATH THE SILVER CUPOLA, IN WHICH A LENS CAPTURES THE LIGHT EMITTED BY THE TRAPPED IONS.

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CREDIT: ETH ZURICH / PAVEL HRMO




The energy states of electrons in an atom follow the laws of quantum mechanics: they are not continuously distributed but restricted to certain well-​defined values – this is also called quantisation. Such quantised states are the basis for quantum bits (qubits), with which scientists want to build extremely powerful quantum computers. To that end, the atoms have to be cooled down and trapped in one place.

Strong trapping can be achieved by ionising the atoms, which means giving them an electric charge. However, a fundamental law of electromagnetism states that electric fields that are constant in time cannot trap a single charged particle. By adding an oscillating electromagnetic field, on the other hand, one obtains a stable ion trap, also known as a Paul trap.

In this way, it has been possible in recent years to build quantum computers with ion traps containing around 30 qubits. Much larger quantum computers, however, cannot straightforwardly be realised with this technique. The oscillating fields make it difficult to combine several such traps on a single chip, and using them heats up the trap – a more significant problem as systems get larger. Meanwhile transport of ions is restricted to pass along linear sections connected by crosses.

Ion trap with a magnetic field

A team of researchers at ETH Zurich led by Jonathan Home has now demonstrated that ion traps suitable for use in quantum computers can also be built using static magnetic fields instead of oscillating fields. In those static traps with an additional magnetic field, called Penning traps, both arbitrary transport and the necessary operations for the future super-​computers were realized. The researchers recently published their results in the scientific journal Nature.

“Traditionally, Penning traps are used when one wants to trap very many ions for precision experiments, but without having to control them individually”, says PhD student Shreyans Jain: “By contrast, in the smaller quantum computers based on ions, Paul traps are used.”

The idea of the ETH researchers to build future quantum computers also using Penning traps was initially met with scepticism by their colleagues. For various reasons: Penning traps require extremely strong magnets, which are very expensive and rather bulky. Also, all previous realizations of Penning traps had been very symmetric, something that the chip-​scale structures used at ETH violate. Putting the experiment inside a large magnet makes it difficult to guide the laser beams necessary for controlling the qubits into the trap, while strong magnetic fields increase the spacing between the energy states of the qubits. This, in turn, makes the control laser systems much more complex: instead of a simple diode laser, several phase-​locked lasers are needed.

Transport in arbitrary directions

Home and his collaborators were not deterred by those difficulties, however, and constructed a Penning trap based on a superconducting magnet and a microfabricated chip with several electrodes, which was produced at the Physikalisch-​Technische Bundesanstalt in Braunschweig. The magnet used delivers a field of 3 Tesla, almost 100’000 times stronger than Earth’s magnetic field. Using a system of cryogenically cooled mirrors, the Zurich researchers managed to channel the necessary laser light through the magnet to the ions.

The efforts paid off: a single trapped ion, which can stay in the trap for several days, could now be moved arbitrarily on the chip, connecting points “as the crow flies” by controlling the different electrodes – this is something not previously possible with the old approach based on oscillating fields. Since no oscillating fields are needed for trapping, many of those traps can be packed onto a single chip. “Once they are charged up, we can even completely isolate the electrodes from the outside world and thus investigate how strongly the ions are disturbed by external influences”, says Tobias Sägesser, who was involved in the experiment as a PhD student.

Coherent control of the qubit

The researchers also demonstrated that the qubit energy states of the trapped ion could also be controlled while maintaining quantum mechanical superpositions. Coherent control worked both with the electronic (internal) states of the ion and the (external) quantised oscillation states as well as for coupling the internal and external quantum states. This latter is a prerequisite for creating entangled states, which are important for quantum computers.

As a next step, Home wants to trap two ions in neighbouring Penning traps on the same chip and thus demonstrate that quantum operations with several qubits can also be performed. This would be the definitive proof that quantum computers can be realized using ions in Penning traps. The professor also has other applications in mind. For instance, since the ions in the new trap can be moved flexibly, they can be used to probe electric, magnetic or microwave fields near surfaces. This opens up the possibility to use these systems as atomic sensors of surface properties.

Moving a single trapped ion in a two-​dimensional plane and illuminating it with a laser beam allows the researchers to create the ETH logo. The image is formed averaging over many repetitions of the transport sequence.

CREDIT

(Photograph montage: ETH Zurich / Institute for Quantum Electronics)

 

Small amounts of licorice raise blood pressure


Peer-Reviewed Publication

LINKÖPING UNIVERSITY





It is known that large amounts of liquorice cause high blood pressure. A study by researchers at Linköping University, Sweden, now shows that even small amounts of liquorice raise blood pressure. The individuals who react most strongly also show signs of strain on the heart.

Liquorice is produced from the root of plants of the Glycyrrhiza species and has long been used as a herbal remedy and flavouring. However, it is known that eating liquorice can also raise blood pressure. This is mainly due to a substance called glycyrrhizic acid that affects the body’s fluid balance through effects on an enzyme in the kidney. High blood pressure, in turn, increases the risk of cardiovascular disease.

Both the European Union and the World Health Organization have concluded that 100 mg of glycyrrhizic acid per day is probably safe to eat for most individuals. But some people eat more liquorice than that. The Swedish Food Agency has estimated that 5 per cent of Swedes have an intake higher than this level.

In the current study, published in The American Journal of Clinical Nutrition, researchers at Linköping University wanted to test whether the limit stated as likely safe actually is so or not.

It is not easy to know how much glycyrrhizic acid is in the liquorice you eat, as its concentration in different liquorice products varies greatly. This variation may depend on factors such as origin, storage conditions and liquorice root species. In addition, the amount of glycyrrhizic acid is not indicated on many products. The Linköping University study is the first to have carefully measured the amount of glycyrrhizic acid in the liquorice that was tested, while being randomised and having a control group.

In the study, 28 women and men aged 18–30 were instructed to eat liquorice, or a control product that did not contain any liquorice, over two periods of time. The control product instead contained salmiak, which gives salty liquorice its flavour. The liquorice weighed 3.3 grammes and contained 100 mg of glycyrrhizic acid, that is, the amount indicated as likely safe for most people to eat daily. Participants were randomly assigned to eat either liquorice or the control product for two weeks, take a break for two weeks, and then eat the other variety for two weeks. This enabled the researchers to compare the effect of both varieties in the same person. The study participants were asked to measure their blood pressure at home every day. At the end of each intake period, the researchers measured levels of various hormones, salt balance, and heart workload.

“In the study, we found that a daily intake of liquorice containing 100 mg glycyrrhizic acid raised blood pressure in young healthy people. This hasn’t previously been shown for such small amounts of liquorice,” says Peder af Geijerstam, doctoral student at the Department of Health, Medicine and Caring Sciences at Linköping University, general practitioner, and lead author of the study.

When the participants ate liquorice, their blood pressure increased by an average of 3.1 mmHg. The researchers also measured two hormones that are affected by liquorice and that regulate fluid balance: renin and aldosterone. The levels of both of these decreased when eating liquorice. The quarter of the study participants who were most sensitive, based on their levels of the hormones renin and aldosterone decreasing the most after eating liquorice, also gained slightly in weight, most likely due to an increased amount of fluid in the body. This group also had elevated levels of a protein that the heart secretes more of when it needs to work harder to pump around the blood in the body, N-terminal pro-brain natriuretic peptide (NT-proBNP). This suggests increased fluid volume and heart workload in the individuals most sensitive to the effects of liquorice.

“Our results give reason to be more cautious when it comes to recommendations and labelling for food containing liquorice,” says Fredrik Nyström, professor at the same department, who was responsible for the study.

The study was funded with support from, among others, The Strategic Research Network in Circulation and Metabolism (LiU-CircM) at Linköping University, The National Research School in General Practice at Umeå University, King Gustaf V and Queen Victoria Freemason Foundation and Region Östergötland.

Article: A low dose of daily licorice intake affects renin, aldosterone, and home blood pressure in a randomized crossover trial, Peder af Geijerstam, Annelie Joelsson, Karin RÃ¥dholm and Fredrik Nyström, (2024). American Journal of Clinical Nutrition, Vol. 119 No. 3-682-692. Published online 20 January 2024, doi: 10.1016/j.ajcnut.2024.01.011