UBC research helps migrating salmon survive mortality hot-spot

UNIVERSITY OF BRITISH COLUMBIA

 

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MOSSOM VOLUNTEER BRIAN LARSON IS GENTLY RELEASING TAGGED COHO INTO BURRARD INLET FROM THE IOCO BOAT CLUB IN PORT MOODY.

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CREDIT: PHOTO CREDIT: MOSSOM CREEK HATCHERY

When Kevin Ryan and the other hardworking volunteers at Mossom Creek Hatchery in Port Moody, B.C. release young coho smolts into the ocean, they’re never quite certain how many will return as adults.

Mossom releases between 5,000 and 10,000 coho smolts each year, and is one of the few hatcheries to release coho directly into the ocean, rather than into a river. Until now, no research had looked at the success of direct ocean releases of coho.

UBC researchers used acoustic telemetry to tag and track coho on their journey. The results were revealing: only 60 per cent of the fish remained alive three kilometres from release. Fewer than one-quarter reached the Lions Gate Bridge 20 kilometres away.

“While low survival is not surprising during this life stage, we discovered that most mortality occurred close to the release location, likely due to predators,” said Dr. Scott Hinch, a professor in the department of forest and conservation sciences who heads the Pacific Salmon Ecology and Conservation Lab at UBC.

“Our results confirm recent studies that Burrard Inlet is a ‘mortality hot-spot’ for juvenile salmon but also suggests ways to increase the fish’s chances of survival, such as by changing the locations and ways of releasing fish.”

The hatchery will start testing different release locations, including various marine sites, and also directly into Mossom Creek.

“With the guidance of Dr. Hinch’s team, we’ll tag and monitor these fish from their release as smolts through to their return as adults to determine which approaches work best,” said Ryan, the hatchery president.

Like other community hatcheries, Mossom’s primary focus is on public education about natural resources and acting as stewards of local salmon creeks.

“As salmon runs continue to decline,” Dr. Hinch noted, “it is more important than ever to support community and volunteer-led hatcheries to improve ways to help these fish surviving their remarkable journey.”

Dr. Hinch and Mr. Ryan are available for interviews. Interview language(s): English

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JOURNAL

North American Journal of Fisheries Management

DOI

10.1002/nafm.10979 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Acoustic telemetry tracking of Coho Salmon smolts released from a community-run hatchery into a marine inlet reveals low early ocean survival

 21ST CENTURY ALCHEMY

Energy scientists unravel the mystery of gold’s glow

EPFL researchers have developed the first comprehensive model of the quantum-mechanical effects behind photoluminescence in thin gold films; a discovery that could drive the development of solar fuels and batteries.

ECOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE

Luminescence, or the emission of photons by a substance exposed to light, has been known to occur in semiconductor materials like silicon for hundreds of years. The nanoscale behavior of electrons as they absorb and then re-emit light can tell researchers a great deal about the properties of semiconductors, which is why they are often used as probes to characterize electronic processes, like those occurring inside solar cells.

In 1969, scientists discovered that all metals luminesce to some degree, but the intervening years failed to yield a clear understanding of how this occurs. Renewed interest in this light emission, driven by nanoscale temperature mapping and photochemistry applications, has reignited the debate surrounding its origins. But the answer was still unclear – until now.

“We developed very high-quality metal gold films, which put us in a unique position to elucidate this process without the confounding factors of previous experiments,” says Giulia Tagliabue, head of the Laboratory of Nanoscience for Energy Technologies (LNET) in the School of Engineering.

In a recent study published in Light: Science and Applications, Tagliabue and the LNET team focused laser beams at the extremely thin – between 13 and 113 nanometers – gold films, and then analyzed the resulting faint glow. The data generated from their precise experiments was so detailed – and so unexpected – that they collaborated with theoreticians at the Barcelona Institute of Science and Technology, the University of Southern Denmark, and the Rensselaer Polytechnic Institute (USA) to rework and apply quantum mechanical modelling methods.

The researchers’ comprehensive approach allowed them to settle the debate surrounding the type of luminescence emanating from the films – photoluminescence – which is defined by the specific way electrons and their oppositely charged counterparts (holes) behave in response to light. It also allowed them to produce the first complete, fully quantitative model of this phenomenon in gold, which can be applied to any metal.

Unexpected quantum effects

Tagliabue explains that, using a thin film of monocrystalline gold produced with a novel synthesis technique, the team studied the photoluminescence process as they made the metal thinner and thinner. “We observed certain quantum mechanical effects emerging in films of up to about 40 nanometers, which was unexpected, because normally for a metal, you don’t see such effects until you go well below 10 nm,” she says.

These observations provided key spatial information about exactly where the photoluminescence process occurred in the gold, which is a prerequisite for the metal’s use as a probe. Another unexpected outcome of the study was the discovery that the gold’s photoluminescent (Stokes) signal could be used to probe the material’s own surface temperature – a boon for scientists working at the nanoscale.

“For many chemical reactions on the surface of metals, there is a big debate about why and under what conditions these reactions occur. Temperature is a key parameter, but measuring temperature at the nanoscale is extremely difficult, because a thermometer can influence your measurement. So, it’s a huge advantage to be able to probe a material using the material itself as the probe,” Tagliabue says.

A gold standard for solar fuel development

The researchers believe their findings will allow metals to be used to obtain unprecedentedly detailed insights into chemical reactions, especially those involved in energy research. Metals like gold and copper – the LNET’s next research target – can trigger certain key reactions, like the reduction of carbon dioxide (CO2) back into carbon-based products like solar fuels, which store solar energy in chemical bonds.

“To combat climate change, we are going to need technologies to convert CO2 into other useful chemicals one way or another,” says LNET postdoc Alan Bowman, the study’s first author.

“Using metals is one way to do that, but if we don’t have a good understanding of how these reactions happen on their surfaces, then we can’t optimize them. Luminescence offers a new  way to understand what is happening in these metals.”

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JOURNAL

Light Science & Applications

DOI

10.1038/s41377-024-01408-2 

METHOD OF RESEARCH

Experimental study

ARTICLE TITLE

Quantum-mechanical effects in photoluminescence from thin crystalline gold films

ARTICLE PUBLICATION DATE

19-Apr-2024

 

Stopping ransomware in its tracks: New enterprise app integrates AI & University research

CYSANA (CYberSecurity ANAlytics) is a new AI-based enterprise solution to protect against malware and ransomware announced today by the cybersecurity company Conatix, in collaboration with the University of Luxembourg’s SnT.

UNIVERSITY OF LUXEMBOURG

 

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CYSANA VISUALIZES SOFTWARE APPLICATIONS AS IMAGES TO DETECT MALWARE EMBEDDED IN EXECUTABLE FILES AT THE POINT OF DOWNLOAD, BEFORE THESE FILES OPEN.

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CREDIT: CYSANA © CONATIX

17 April 2024, Luxembourg and Potomac Falls, USA – CYSANA (CYberSecurity ANAlytics) is a new AI-based enterprise solution to protect against malware and ransomware announced today by the cybersecurity company Conatix, in collaboration with the University of Luxembourg’s Interdisciplinary Centre for Security, Reliability and Trust (SnT).

CYSANA stops malware and ransomware before they have an impact on business. It does this by integrating the most recent developments in deep learning neural network-based image classification and anti-encryption research.

The core of CYSANA lies in its AI module, which uniquely visualizes software applications as images to detect malware embedded in executable files at the point of download, before these files open, install or engage in any activity on a computer. The CYSANA anti-encryption module further strengthens this defense by preventing malware from using a computer’s own encryption keys to encrypt user data and hold it for ransom, effectively blocking malware from any source from becoming ransomware.

 Is it malware or not? Is it safe to run?

Malware and ransomware pose two of the greatest, and fastest-growing, cyber threats in the world today. Malware can be hidden in executable software files and remain undetected for long periods while monitoring user activity and corporate operating procedures or stealing or deleting data. In its most antagonistic form, malware transforms into ransomware, encrypting valuable data on computers, often demanding a ransom to reverse the damage.  In July 2023, Reuters reported close to $450 million  had been paid to ransomware attackers in the first half of that year, an increase of $175 million over the same period in 2022.  The impacts of both malware and ransomware can be devastating to companies and government agencies, with attacks becoming more frequent, sophisticated and costly. 

 

CYSANA Empowers Cybersecurity Excellence with an Innovative Approach to Advancing Expertise

“Our innovative CYSANA software merges deep learning and anti-encryption technologies to offer a new level of robust cyber protection,” said David Lehrer, CEO of Conatix. “Developing this solution has been a true collaboration resulting in more robust and encompassing cyber protection than a single company could develop on its own.”

“SnT strives to conduct research with an impact, and this product launch is a significant success story for that mission,” said Dr. Carlo Duprel, head of the SnT’s Technology Transfer Office of the University of Luxembourg. “The collaboration with Conatix to launch CYSANA to a worldwide market underlines our depth of expertise in the field of cybersecurity, and commitment to combatting cybercrime.”

In the development process CYSANA’s neural network models were trained and tested on the Luxembourg-based MeluXina supercomputer operated by LuxProvide. This high-performance computer testing ground, one of the most powerful in Europe, helped make the product effective at detecting novel and zero-day malicious files. 

“LuxProvide is passionate about driving innovation and research, as demonstrated by our significant support for the CYSANA project, along with our commitment to offering a leading platform for digital and other research initiatives.” stated Arnaud Lambert, CEO of LuxProvide.

With the launch of CYSANA, Conatix is offering a deep learning AI-based solution against some of the hardest-to-find malware, a solution that is faster and more effective than existing anti-malware systems. CYSANA is a barrier for those malware that could become ransomware and start encrypting valuable company data. The anti-ransomware solution within the Cysana product is patented by the University of Luxembourg in 15 countries. Cysana’s exclusive license with the University of Luxembourg’s SnT is another step from the Centre to strengthen the impact of its research at a global scale.

As cyber threats like malware and ransomware escalate, the Conatix CYSANA software offers a vital solution to protect businesses and government agencies. It recently won the AI & Data category of the 2024 Product Awards, delivered by Products That Count. The initial release of Cysana is directed at selected cybersecurity service providers (MSPs) and CISO teams in North America and Europe by invitation only.

 

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Conatix has won numerous international innovation awards, including being named one of the most innovative cybersecurity startups in the UK by the UK government cybersecurity directorate two years in a row and being listed in the global CyberTech 100 list of the most innovative cybersecurity startups in the world for banking.  Conatix is an early-stage AI for cybersecurity startup based near Washington DC, and in New York, Montreal, London and Berlin.  Collaboration by Conatix with the University of Luxembourg on this software product R&D was supported by the EIT Digital Innovation Factory innovation grant program part-funded by the European Union.  www.cysana.co and www.conatixcyber.com 

LuxProvide is at the forefront of digital intelligence, combining data science expertise with supercomputing capabilities. Centered around MeluXina, Luxembourg's advanced supercomputer, LuxProvide focuses on accuracy, security, and sustainability in the digital realm. The company transcends traditional technological boundaries, fostering innovative solutions that elevate the human experience and drive positive change. LuxProvide is dedicated to pioneering a future where technology not only evolves but enhances every aspect of life. Learn more: https://www.luxprovide.lu/

The Interdisciplinary Centre for Security, Reliability and trust (SnT) of the University of Luxembourg, founded in 2009, promotes and conducts research in socio-technical security and cybersecurity in collaboration with other disciplines.  The Sociotechnical Cybersecurity (IRiSC) research group within SnT conducts forward-looking theoretical and experimental research on cybersecurity and online privacy based on the interdisciplinary expertise of its members.  IRiSC integrates methods from social sciences and legal analysis into computer science to address the complexity of reliable, secure and trustworthy systems and the multiple factors leading to misuses and cyberattacks. https://www.uni.lu/snt-en/research-groups/irisc/

The University of Luxembourg is an international research university with a distinctly multilingual and interdisciplinary character. The University was founded in 2003 and counts close to 7,000 students and more than 2,400 employees from around the world. The University has three missions: research, higher education, and contribution to the social, cultural and economic development of the country. The University’s strategic development areas are digital transformation, medicine and health, and sustainable and societal development. The University has three faculties (Science, Technology and Medicine; Law, Economy and Finance; Humanities, Education and Social Sciences) and four interdisciplinary research centres (Interdisciplinary Centre for Security, Reliability and Trust - SnT; Luxembourg Centre for Systems Biomedicine - LCSB; Luxembourg Centre for Contemporary and Digital History – C²DH; Luxembourg Centre for European Law – LCEL). The University offers 18 Bachelor and 46 Master study programmes, and has four doctoral schools. Times Higher Education ranks the University of Luxembourg #4 worldwide for its “international outlook,” #25 in the Young University Ranking 2023 and among the top 250 universities worldwide.

 

 

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METHOD OF RESEARCH

Imaging analysis

 

KAIST develops sodium battery capable of rapid charging in just a few seconds​

THE KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY (KAIST)

 

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FIGURE 1. SCHEMATIC SYNTHETIC PROCEDURES OF HIGH-CAPACITY/HIGH-RATE ANODE AND CATHODE MATERIALS FOR A SODIUM-ION HYBRID ENERGY STORAGES (SIHES) AND THEIR PROPOSED ENERGY STORAGE MECHANISMS. SYNTHETIC PROCEDURES FOR (A) ULTRAFINE IRON SULFIDE-EMBEDDED S-DOPED CARBON/GRAPHENE (FS/C/G) ANODE AND (B) ZEOLITIC IMIDAZOLATE FRAMEWORK-DERIVED POROUS CARBON (ZDPC) CATHODE MATERIALS. (C) PROPOSED ENERGY STORAGE MECHANISMS OF NA+ IONS IN FS/C/G ANODE AND CLO-4 IONS IN ZDPC CATHODE FOR AN SIHES. 

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CREDIT: KAIST NANO MATERIALS SIMULATION AND FABRICATION LAB.

Sodium (Na), which is over 500 times more abundant than lithium (Li), has recently garnered significant attention for its potential in sodium-ion battery technologies. However, existing sodium-ion batteries face fundamental limitations, including lower power output, constrained storage properties, and longer charging times, necessitating the development of next-generation energy storage materials.

On the 11th of April, KAIST (represented by President Kwang Hyung Lee) announced that a research team led by Professor Jeung Ku Kang from the Department of Materials Science and Engineering had developed a high-energy, high-power hybrid sodium-ion battery capable of rapid charging. 

The innovative hybrid energy storage system integrates anode materials typically used in batteries with cathodes suitable for supercapacitors. This combination allows the device to achieve both high storage capacities and rapid charge-discharge rates, positioning it as a viable next-generation alternative to lithium-ion batteries.

However, the development of a hybrid battery with high energy and high power density requires an improvement to the slow energy storage rate of battery-type anodes as well as the enhancement of the relatively low capacity of supercapacitor-type cathode materials. 

< Figure 1. Schematic synthetic procedures of high-capacity/high-rate anode and cathode materials for a sodium-ion hybrid energy storages (SIHES) and their proposed energy storage mechanisms. Synthetic procedures for (a) ultrafine iron sulfide-embedded S-doped carbon/graphene (FS/C/G) anode and (b) zeolitic imidazolate framework-derived porous carbon (ZDPC) cathode materials. (c) Proposed energy storage mechanisms of Na+ ions in FS/C/G anode and ClO-4 ions in ZDPC cathode for an SIHES. >

To account for this, Professor Kang's team utilized two distinct metal-organic frameworks for the optimized synthesis of hybrid batteries. This approach led to the development of an anode material with improved kinetics through the inclusion of fine active materials in porous carbon derived from metal-organic frameworks. Additionally, a high-capacity cathode material was synthesized, and the combination of the cathode and anode materials allowed for the development of a sodium-ion storage system optimizing the balance and minimizing the disparities in energy storage rates between the electrodes.

The assembled full cell, comprising the newly developed anode and cathode, forms a high-performance hybrid sodium-ion energy storage device. This device surpasses the energy density of commercial lithium-ion batteries and exhibits the characteristics of supercapacitors' power density. It is expected to be suitable for rapid charging applications ranging from electric vehicles to smart electronic devices and aerospace technologies.

< Figure 2. Electrochemical characterizations of FS/C/G-20//ZDPC SIHES full cells (left). Ragone plots for FS/C/G-20//ZDPC (this work) and other previously reported sodium-ion electrochemical energy storage devices (right). >

Professor Kang noted that the hybrid sodium-ion energy storage device, capable of rapid charging and achieving an energy density of 247 Wh/kg and a power density of 34,748 W/kg, represents a breakthrough in overcoming the current limitations of energy storage systems. He anticipates broader applications across various electronic devices, including electric vehicles.

This research, co-authored by KAIST doctoral candidates Jong Hui Choi and Dong Won Kim, was published in the international journal Energy Storage Materials on March 29 with the title "Low-crystallinity conductive multivalence iron sulfide-embedded S-doped anode and high-surface-area O-doped cathode of 3D porous N-rich graphitic carbon frameworks for high-performance sodium-ion hybrid energy storages."

The study was conducted with support from the Ministry of Science and ICT and the National Research Foundation of Korea through the Nanomaterial Technology Development Project.

Figure 2. Electrochemical characterizations of FS/C/G-20//ZDPC SIHES full cells (left). Ragone plots for FS/C/G-20//ZDPC (this work) and other previously reported sodium-ion electrochemical energy storage devices (right). 

CREDIT

KAIST Nano Materials Simulation and Fabrication Lab.

JOURNAL

Energy Storage Materials

DOI

10.1016/j.ensm.2024.103368 

METHOD OF RESEARCH

Meta-analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Low-crystallinity conductive multivalence iron sulfide-embedded S-doped anode and high-surface area O-doped cathode of 3D porous N-rich graphitic carbon frameworks for high-performance sodium-ion hybrid energy storages

 New research shines a light on how expert mapmakers at Ordnance Survey see the world differently

Peer-Reviewed Publication

ASTON UNIVERSITY

 

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OS REMOTE SENSING SERVICES SURVEY TEAM UPDATING OS MASTERMAP USING THE LATEST AERIAL IMAGERY (CREDIT: ORDNANCE SURVEY)

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CREDIT: ORDNANCE SURVEY

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• Aston University psychologists worked with Ordnance Survey to assess how surveyors use 3D aerial images when making maps
• Humans naturally assume light comes from above, but experienced surveyors can interpret visual cues to assess topography regardless of the light direction
• It is the first time it has been shown that experience can radically alter natural human assumptions about lighting and could improve surveyor training.

Researchers at Aston University have found differences between experienced Ordnance Survey (OS) mapmakers and novices in the way that they interpret aerial images for mapmaking, which could lead to improved training processes for new recruits.

OS is well known for its travel and walking maps, but is also responsible for maintaining Great Britain’s national geographic database. Every time a building is demolished or developed, or a new road and path built, the map must be updated.

Aerial photographs are taken of the area that has changed, either from a plane or using drones, and expert mapmakers, known as remote sensing surveyors, will examine the images to identify change and accurately redraw the map of the area.

Image pairs are presented stereoscopically, one to each eye, allowing the remote sensing surveyors to see in 3D and correctly assess the topography, such as ditches, hills and hedges.

Led by Professor Andrew Schofield, a team from Aston University’s College of Health and Life Sciences, together with Dr Isabel Sargent, previously at OS, carried out a study to understand how remote sensing surveyors interpret the shadows and highlights in images.

The researchers asked six trained remote sensing surveyors and six novices to assess 10,000 stereoscopic aerial images of hedges and ditches, which had been heavily masked with image distortions.

The stereoscopic images the aerial surveyors use for mapmaking are usually taken on sunny days. The human brain is naturally wired to interpret light as coming from above. However, the light does not come from above in the OS aerial images, it depends on the position of the sun. In the UK, north of the equator, light comes slightly from the south, thus appearing to come from below in images viewed by the surveyors.

The researchers wanted to see how manipulating the direction of the light would affect the surveyors.

Professor Schofield and the team swapped the image pairs between the eyes in half of the trials, so that hedges might look like ditches, and ditches look like hedges. The images were also flipped vertically on half the trials, changing the direction of the light source.

Expert surveyors were found to rely on the stereoscopic cues – the difference in images seen by the two eyes – when performing the task.

Novices were more likely to rely on lighting cues – highlights and shadows – to judge the shape and relief of an object, and assumed, as is natural, that the lighting came from above.

With the manipulated images, this meant that novices frequently made mistakes. Experts were more accurate, even when the images had been turned upside down, and some had learnt to assume that the light source came from the south, or below.

This is the first time anyone has shown that the natural assumption that light comes from above, which is common amongst many animal species, can be changed through long term experience. The researchers say that it could be used to develop new visual training techniques for remote sensing surveyors. For example, intensive exposure to repeated, difficult images can improve performance via a process called perceptual learning.

Professor Schofield said:

“This is a very exciting result. Others have shown that the light-from-above assumption can be altered by a few degrees, but no one has ever found complete reversals following long term experience.

Dr Sargent said:

“This result will help Ordnance Survey to understand the expertise of their staff and improve surveyor training and procedures.”

Remote sensing surveyor Andy Ormerod, who worked on the study, said:

“This research proves that experienced remote sensing surveyors can see the world differently. Whereas non-surveyors are used to seeing the world from one perspective, our brains have learned to view the world as seen from aerial imagery.”

Journal of Vision DOI:10.1167/jov.24.4.11

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JOURNAL

Journal of Vision

DOI

10.1167/jov.24.4.11 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Classification images for aerial images capture visual expertise for binocular disparity and a prior for lighting from above

ARTICLE PUBLICATION DATE

16-Apr-2024

 

Ghost particle on the scales

Peer-Reviewed Publication

MAX-PLANCK-INSTITUT FUR KERNPHYSIK

 

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AN EXTREMELY PRECISE ATOMIC BALANCE: PENTATRAP CONSISTS OF FIVE PENNING TRAPS ARRANGED ONE ABOVE THE OTHER (YELLOW TOWER IN THE MIDDLE). IN THESE IDENTICALLY CONSTRUCTED TRAPS, IONS IN THE EXCITED QUANTUM STATE AND IN THE GROUND STATE CAN BE MEASURED IN COMPARISON. IN ORDER TO MINIMIZE UNCERTAINTIES, THE IONS ARE ALSO MOVED BACK AND FORTH BETWEEN DIFFERENT TRAPS FOR COMPARATIVE MEASUREMENTS.

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CREDIT: MPIK

In the 1930s, it turned out that neither the energy nor the momentum balance is correct in the radioactive beta decay of an atomic nucleus. This led to the postulate of "ghost particles" that "secretly" carry away energy and momentum. In 1956, experimental proof of such neutrinos was finally obtained. The challenge: neutrinos only interact with other particles of matter via the weak interaction that is also underlying the beta decay of an atomic nucleus. For this reason, hundreds of trillions of neutrinos from the cosmos, especially the sun, can pass through our bodies every second without causing any damage. Extremely rare neutrino collisions with other particles of matter can only be detected with huge detectors.

Solar neutrinos brought another ground-breaking revelation: the three types of neutrino known to date can transform into each other. However, these "neutrino oscillations" had a serious consequence for the world view of particle physics. Previously, it was assumed that neutrinos had no rest mass, like photons. This would be compatible with the standard model of particle physics, the best description of the particle world to date. However, the oscillations forced a rest mass for neutrinos - a further indication that new physics must exist beyond the standard model.

Knowing the exact rest mass of the neutrino would therefore be an open sesame into the unknown world of new physics. Unfortunately, you cannot simply place a neutrino on a scale. This requires extremely complex experiments on technically accessible physical processes involving neutrinos. "One way is the beta decay of tritium," explains Christoph Schweiger, doctoral student in Klaus Blaum's department at the Max Planck Institute for Nuclear Physics. Here, one of the two neutrons in the superheavy hydrogen decays into a proton and emits an electron and a neutrino, thereby transforming the atom into lighter helium. This process is "weighed" by the KATRIN experiment at the Karlsruhe Institute of Technology.

"The complementary path is the electron capture of the artificial isotope holmium-163," continues Schweiger. Here, the atomic nucleus captures an electron from the inner electron shell, whereby a proton is converted into a neutron, resulting in the element dysprosium-163. This also releases a neutrino, amongst other things. The international ECHo collaboration, in which the Heidelberg scientists are involved, attempts to measure this decay process energetically with extreme precision. According to Einstein's E = mc2, mass and energy are equivalent, so measuring energy can be equated with weighing masses.  As a "calorimeter", ECHo measures extremely accurately the total energy released in this decay: This corresponds to a maximum of the Q value minus the rest mass of the neutrino released. For this purpose, the holmium-163 isotope is incorporated into a layer of gold atoms.

"However, these gold atoms could have an influence on holmium-163," explains Schweiger: "It is therefore important to measure the value of Q as precisely as possible using an alternative method and to compare it with the calorimetrically determined value in order to detect possible systematic sources of error." This is where the Heidelberg pentatrap experiment and Schweiger's doctoral thesis come into play. Pentatrap consists of five so-called Penning traps. In these traps, electrically charged atoms can be captured in a combination of a static electric and magnetic field. These ions perform an intricate "circle dance", which allows their mass to be determined with extreme precision. "With an Airbus A-380 with a maximum load, you could use this sensitivity to determine whether a single drop of water has landed on it," says the physicist, illustrating the capabilities of this super scale.

In principle, a Penning trap works like a swing. If you place two children of different weights next to each other on two swings of the same type and push them equally hard, you will gradually observe a shift in the swing frequencies. This can be used to calculate the difference in weight between the two children. In the case of the pentatrap experiment, this is the difference in mass between a holmium-163 ion and a dysprosium-163 ion. In addition, the faster both children swing, the sooner the result is obtained, which is also much more accurate for the same observation time than for slow swinging. For this reason, the team removed 38, 39 and 40 electrons from the "highly charged" ions in three different series of measurements, which makes their "circle dance" considerably faster. "If everything works, a measurement will only take a few weeks," says Schweiger.

From the differences in mass as a result of various frequency measurements, via E = mc2 the Heidelberg scientists were finally able to determine a Q value for electron capture that was 50 times more precise than before. "The contribution of the three theory groups, including Christoph Keitel's group here at the institute, was just as important as our measurement," emphasises Schweiger. In addition to the frequency difference between the two ions, a second variable has a significant influence on the Q value determined: the energy stored in the remaining electron system of a highly charged ion. As such a large ion is a multi-particle system, the calculation was correspondingly complex. It turned out that the calculations resulted in almost exactly the same Q values for the three measured charge states with 38, 39 and 40 electrons removed. This made it clear that systematic uncertainties in experiment and theory could be ruled out, Schweiger emphasises enthusiastically. And what does this mean for the neutrino masses?

KATRIN determined the most precise upper limit to date of the neutrino mass by "weighing" at 0.8 electron volt per speed of light squared, which corresponds to an unimaginable 0.0000000000000000000000000000000000014 kilogram! This order of magnitude of 10–36 corresponds approximately to the weight ratio between four raisins and the sun.  And that is only an upper limit. The analysis of the estimated mass distribution in the universe even arrives at a significantly lower upper limit of the neutrino masses of 0.12 electron volt per speed of light squared. "However, this analysis is highly complex and depends on the cosmological model used," says Schweiger. In any case, it is clear that anyone who wants to weigh neutrinos faces extreme challenges at the edge of what is technically possible. Against this background, the Heidelberg result is a major step forward on the way to solving the mystery of neutrino masses.

(Roland Wengenmayr / MPIK)

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JOURNAL

Nature Physics

DOI

10.1038/s41567-024-02461-9 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Direct high-precision Penning-trap measurement of the Q-value of the electron capture in 163Ho for the determination of the electron neutrino mass

ARTICLE PUBLICATION DATE

19-Apr-2024

 

Climate change will increase value of residential rooftop solar panels across US, study shows

UNIVERSITY OF MICHIGAN

 

 

Graphic

Climate change will increase the future value of residential rooftop solar panels across the United States by up to 19% by the end of the century, according to a new University of Michigan-led study.

 

The study defines the value of solar, or VOS, as household-level financial benefits from electricity bill savings plus revenues from selling excess electricity to the grid—minus the initial installation costs.

 

For many U.S. households, increased earnings from residential rooftop solar could total up to hundreds of dollars annually by the end of the century, say the authors of the study, which is scheduled for publication April 19 in the journal Nature Climate Change.

 

"Given the average 25-year lifespan of a rooftop solar installation, a system built today will nearly experience 2050 weather," said study senior author Michael Craig, assistant professor of energy systems at the U-M School for Environment and Sustainability and of industrial and operations engineering at U-M's College of Engineering.

 

"So, it's important for households to think of future value when building solar. If households do so, our findings indicate they would see even greater value from solar,  and might decide to build more." 

 

Public awareness of the increased future value of rooftop solar could spur greater adoption of the technology, which in turn could accelerate efforts to decarbonize the power-generation system in the United States and globally, the study shows.

 

The expected financial gains seen in the study were driven largely by increased demand for residential air-conditioning as the climate warms. The other key factor affecting the value of rooftop photovoltaic systems, the researchers say, is future solar-panel performance in response to climate change.

 

Craig and colleagues analyzed data from 2,000 households in 17 U.S. cities and estimated air-conditioning demand and solar-panel performance under future climates using a moderate climate-warming scenario called RCP-4.5.

 

The value of rooftop solar panels increased in nearly all the cities, in both warm and cold locations. Miami saw the largest increase in value, while only Minneapolis saw a decrease in the financial benefits of rooftop solar for households.

 

"This is the first study to quantify the value of rooftop solar under climate change, and we show that households across the U.S. will realize greater cost savings from rooftop solar under future weather than under historic weather," said study lead author Mai Shi, a former U-M visiting doctoral student now at Tsinghua University in Beijing.

 

As home-cooling demands rise, a greater proportion of solar-generated electricity will be used to cool the home, rather than being sold to the electrical grid, benefiting owners of rooftop solar systems, according to the study.

 

That's because—in many states—solar energy used to power a home reduces the homeowner's electric bill by the full retail cost of electricity, while electricity that is sent to the grid is credited at a lower rate.

 

"Greater cooling demand means more solar power is consumed at the household rather than sent back to the grid," Craig said. "And it's generally more valuable for a rooftop photovoltaic owner to consume the power generated by their PV panel, rather than exporting it to the grid."

 

Under the moderate RCP-4.5 climate scenario, demand for residential space cooling is expected to increase in all 17 cities studied. Cooling demand will increase by an average of 35% by mid-century and by an average of 64% by the end of the century, across all households in all of the cities, the researchers say.

 

The other key factor affecting the future value of residential rooftop photovoltaics is solar-panel performance in response to rising air temperatures and changes in cloud cover.

 

Solar panels work best in cool, sunny weather. As air temperature or cloud cover increase, the amount of electricity generated by a solar panel declines. The study found that future solar-panel performance will vary from place to place across the U.S., depending on weather conditions.

 

In cities such as Ann Arbor, Austin, Chicago, Dallas, Detroit, Houston, Louisville and Milwaukee, rising air temperatures will decrease solar panel efficiency, but reduced cloud cover will likely increase the amount of sunlight reaching panels, on average. The two factors "are opposing but roughly comparable," meaning they cancel each other out, the researchers say.

 

But cities such as Baltimore, Boston, Los Angeles, Minneapolis, New York City and Phoenix are expected to be both warmer and cloudier in response to climate change, which will "significantly decrease" the electrical output of rooftop solar.

 

Even so, increased cooling demand in all 17 cities will likely outweigh changes in panel electrical output, resulting in financial gains for owners of rooftop solar in nearly every case, according to the study. Minneapolis, where limited future increases in cooling demand will combine with decreased electrical output from rooftop solar panels, is an exception.

 

While future financial gains from rooftop solar will be reaped mainly by households that can afford to install panels, various programs are in place to increase accessibility, so that more people share in the anticipated benefits, Craig says.

 

For example, there are programs that defray the costs of solar, opening it up to lower-income individuals. Governments can also install rooftop solar on public buildings, such as subsidized housing, to cover the capital costs while providing solar benefits to tenants. And community solar programs can benefit entire communities, including households that lack the means or ability to access rooftop solar themselves.

 

In addition to Craig and Shi, the other author of the Nature Climate Change paper is Xi Lu of Tsinghua University.

 

The study was supported by the National Key R&D Program of China, U.S. National Science Foundation, National Natural Science Foundation of China and Carbon Neutrality and Energy System Transformation Project.

 

Study: Climate change will impact the value and optimal adoption of residential rooftop solar (DOI 10.1038/s41558-024-01978-4) (available once embargo lifts)

 

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JOURNAL

Nature Climate Change

DOI

10.1038/s41558-024-01978-4