Prostate cancer risk prediction algorithm could help target testing at men at greatest risk

Cambridge scientists have created a comprehensive tool for predicting an individual’s risk of developing prostate cancer, which they say could help ensure that those men at greatest risk will receive the appropriate testing while reducing unnecessary — and potentially invasive — testing for those at very low risk.

CanRisk-Prostate, developed by researchers at the University of Cambridge and The Institute of Cancer Research, London, will be incorporated into the group’s CanRisk web tool, which has now recorded almost 1.2 million risk predictions. The free tool is already used by healthcare professionals worldwide to help predict the risk of developing breast and ovarian cancers.

Prostate cancer is the most common type of cancer in men. According to Cancer Research UK, over 52,000 men are diagnosed with the disease each year and there are more than 12,000 deaths. Over three-quarters (78%) of men diagnosed with prostate cancer survive for over ten years, but this proportion has barely changed over the past decade in the UK.

Testing for prostate cancer involves a blood test that looks for a protein known as a prostate-specific antigen (PSA) that is made only by the prostate gland; however, it is not always accurate. According to the NHS website, around three in four men with a raised PSA level will not have cancer. Further tests, such as tissue biopsies or MRI scans, are therefore required to confirm a diagnosis.

Professor Antonis Antoniou from the Department of Public Health and Primary Care at the University of Cambridge said: “Prostate cancer is the most common cancer in men in the UK, but population-wide screening based on PSA isn’t an option: these tests are often falsely positive, which means that many men would then be biopsied unnecessarily. Also, many prostate tumours identified by PSA tests are slow-growing and would not have been life-threatening. The treatment of these tumours may do more harm than good.

“What we need is a way of identifying those men who are at greatest risk, allowing us to target screening and diagnostic tests where they are most needed, while also reducing the harms for those men who have low risk of the disease. This is what CanRisk-Prostate aims to do. For the first time, it combines information on the genetic makeup and prostate cancer family history, the main risk factors for the disease, to provide personalised cancer risks.”

Prostate cancer is one of the most genetically determined of common cancers. Inherited faulty versions of the BRCA2, HOXB13 and possibly BRCA1 genes are associated with moderate-to-high risk of prostate cancer, though such faults are rare in the population. In addition, there are several hundred more common genetic variants that each confer a lower risk, but in aggregate they act like ‘volume control’ that moderate or increase the prostate cancer risk.

Writing in the Journal of Clinical Oncology, the researchers — supported by Cancer Research UK — describe the development of the first comprehensive prostate cancer model using genetic and cancer family history data from almost 17,000 families affected by prostate cancer. It uses data on rare genetic faults in moderate-to-high-risk genes and a risk score based on 268 common low-risk variants, together with detailed cancer family history, to predict the future risks.

One in six men (16%) will develop prostate cancer by the time they are 85 years old. Using the model, the team found that the predicted risk was higher for men who had a father diagnosed with prostate cancer — 27% if the father was diagnosed at an older age (80 years) but as high as 42% if the father was diagnosed at a young age (50 years).

The risks were considerably higher for men with genetic faults. For example, 54% of men who carry an alteration in the BRCA2 gene would develop prostate cancer — however, among men with BRCA2 gene faults, the risks were substantially lower if they also had a small number of the low-risk variants, but much higher if they also had a large number of the low-risk variants.

In practice, say the researchers, clinicians will be able to use any combination of cancer family history, rare and common genetic variants to provide a personalised risk.

To validate their model, the team ran the risk model on an independent cohort of over 170,000 men recruited to UK Biobank, a biomedical database and research resource containing anonymised genetic, lifestyle and health information from half a million UK participants. All of these men were free from prostate cancer when they were recruited to the study, but more than 7,600 developed prostate cancer within the subsequent ten years.

When validating their model, the researchers found that 86% of the UK Biobank participants who developed cancer were in the half of men with the highest predicted risks, which suggests that it may be possible to target screening and diagnostic tests to the subgroup of the population at highest risk, among whom the majority of the cancers will occur.

Dr Tommy Nyberg from the MRC Biostatistics Unit at Cambridge said: “We’ve created the most comprehensive tool to date for predicting a man’s risk of developing prostate cancer. We hope this will help clinicians and genetic counsellors assess their clients’ risk and provide the appropriate follow-up.

“Over the next 12 months, we aim to build this tool into the widely used CanRisk tool, which will facilitate the risk-based clinical management of men seen in family cancer clinics and enable risk-adapted early detection approaches to the population at large.”

Professor Ros Eeles from The Institute of Cancer Research, London and co-author on the study said: “This is an important step forward as it will enable clinicians to have conversations with men about their individual risk of prostate cancer based on the most accurate computer model to date. This will help them in making decisions about screening.”

So far, the data used to develop CanRisk-Prostate has been from men of European ancestry. The team hope to be able to include data from men of other ethnicities as further research is undertaken.

The University of Cambridge recently launched the Early Cancer Institute with the aim of detecting cancer early enough to cure it. It is the first physical institute in the UK dedicated to early cancer. A new Cambridge Cancer Research Hospital is also planned for the near future, bringing together clinical and research expertise in a new, world-class hospital, designed in partnership with patients.

There is also an Early Detection and Diagnosis centre at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust where a prostate risk clinic has been established to translate these findings into targeted screening programmes.

The research was supported by the Cancer Research UK-funded CanRisk programme. Additional support for CanRisk-Prostate was provided by Prostate Cancer UK, The Institute of Cancer Research, Everyman Campaign, National Cancer Research Network UK, National Cancer Research Institute, NIHR Cambridge Biomedical Research Centre and the NIHR Biomedical Research Centre at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust.

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Deep-space optical communication demonstration project forges ahead

Researchers report new results from the NASA Deep Space Optical Communications (DSOC) technology demonstration project, which develops and tests new advanced laser sources for deep-space optical communication. The ability to perform free-space optical communication throughout the solar system would go beyond the capabilities of the radio communication systems used now and provide the bandwidth necessary for future space missions to transmit large amounts of data, including high-definition images and video.

The demonstration system consists of a flight laser transceiver, a ground laser transmitter and a ground laser receiver. The downlink transmitter has been installed on the Psyche spacecraft, which will travel to a unique metal asteroid also called Psyche, which orbits the Sun between Mars and Jupiter.

Malcolm. W. Wright, from the Jet Propulsion Laboratory, California Institute of Technology, will present the functional and environmental test results of the DSOC downlink flight laser transmitter assembly and ground uplink transmitter assembly at the Optica Laser Congress, 11 — 15 December 2022.

Validating deep space optical communications will allow streaming back high-definition imagery during robotic and manned exploration of planetary bodies, utilizing resources comparable to state-of-art radio-frequency telecommunications.

Transmitting into deep space

Although free-space optical communications from space to ground have been demonstrated at distances as far away as the moon, extending such links to deep space ranges requires new types of laser transmitters. The downlink flight laser must have a high photon efficiency while supporting near kilowatt peak power. The uplink laser requires multi-kilowatt average powers with narrow linewidth, good beam quality and low modulation rates.

The flight laser transmitter assembly uses a 5 W average power Er-Yb co-doped fiber-based master oscillator power amplifier laser with discrete pulse widths from 0.5 to 8 ns in a polarized output beam at 1550 nm with an extinction ratio of more than 33 dB. The laser passed verification and environmental tests before being integrated into spacecraft. End-to-end testing of the flight laser transmitter with the ground receiver assembly also validated the optical link performance for a variety of pulse formats and verified the interface to the DSOC electronics assembly.

Launching a new approach

The ground uplink transmitter assembly can support optical links with up to 5.6 kW average power at 1064 nm. It includes ten kilowatt-class continuous wavelength fiber-based laser transmitters modified to support the modulation formats. A remotely placed chiller provides thermal management for the lasers and power supplies. The uplink laser will also provide a light beacon onto which the flight transceiver can lock.

“Using multiple individual laser sources that propagate through sub-apertures on the telescope’s primary mirror relieves the power requirement from a single source,” said Wright. “It also allows atmospheric turbulence mitigation and reduces the power density on the telescope mirrors.”

Now that spacecraft-level testing is complete, the Psyche spacecraft — with the flight laser transceiver aboard — will be integrated into a launch vehicle. The DSOC technology demonstration will begin shortly after launch and continue for one year as the spacecraft travels away from Earth and eventually performs a flyby of Mars.

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Hove secondary school pupil dies with suspected strep A

Sixteen children have now died with invasive strep A since September, health officials say.

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Hubble detects ghostly glow surrounding our solar system

Imagine walking into a room at night, turning out all the lights and closing the shades. Yet an eerie glow comes from the walls, ceiling, and floor. The faint light is barely enough to see your hands before your face, but it persists. Sounds like a scene out of “Ghost Hunters?” No, for astronomers this is the real deal. But looking for something that’s close to nothing is not easy. 

One possible explanation is that a shell of dust envelops our solar system all the way out to Pluto, and is reflecting sunlight. Seeing airborne dust caught in sunbeams is no surprise when cleaning the house. But this must have a more exotic origin. Because the glow is so smoothy distributed, the likely source is innumerable comets — free-flying dusty snowballs of ice. They fall in toward the Sun from all different directions, spewing out an exhaust of dust as the ices sublimate due to heat from the Sun. If real, this would be a newly discovered architectural element of the solar system. It has remained invisible until very imaginative and curious astronomers, and the power of Hubble, came along.

Aside from a tapestry of glittering stars, and the glow of the waxing and waning Moon, the nighttime sky looks inky black to the casual observer. But how dark is dark?

To find out, astronomers decided to sort through 200,000 images from NASA’s Hubble Space Telescope and made tens of thousands of measurements on these images to look for any residual background glow in the sky, in an ambitious project called SKYSURF. This would be any leftover light after subtracting the glow from planets, stars, galaxies, and from dust in the plane of our solar system (called zodiacal light).

When researchers completed this inventory, they found an exceedingly tiny excess of light, equivalent to the steady glow of 10 fireflies spread across the entire sky. That’s like turning out all the lights in a shuttered room and still finding an eerie glow coming from the walls, ceiling, and floor.

The researchers say that one possible explanation for this residual glow is that our inner solar system contains a tenuous sphere of dust from comets that are falling into the solar system from all directions, and that the glow is sunlight reflecting off this dust. If real, this dust shell could be a new addition to the known architecture of the solar system.

This idea is bolstered by the fact that in 2021 another team of astronomers used data from NASA’s New Horizons spacecraft to also measure the sky background. New Horizons flew by Pluto in 2015, and a small Kuiper belt object in 2018, and is now heading into interstellar space. The New Horizons measurements were done at a distance of 4 billion to 5 billion miles from the Sun. This is well outside the realm of the planets and asteroids where there is no contamination from interplanetary dust.

New Horizons detected something a bit fainter that is apparently from a more distant source than Hubble detected. The source of the background light seen by New Horizons also remains unexplained. There are numerous theories ranging from the decay of dark matter to a huge unseen population of remote galaxies.

“If our analysis is correct there’s another dust component between us and the distance where New Horizons made measurements. That means this is some kind of extra light coming from inside our solar system,” said Tim Carleton, of Arizona State University (ASU).

“Because our measurement of residual light is higher than New Horizons we think it is a local phenomenon that is not from far outside the solar system. It may be a new element to the contents of the solar system that has been hypothesized but not quantitatively measured until now,” said Carleton.

Hubble veteran astronomer Rogier Windhorst, also of ASU, first got the idea to assemble Hubble data to go looking for any “ghost light.” “More than 95% of the photons in the images from Hubble’s archive come from distances less than 3 billion miles from Earth. Since Hubble’s very early days, most Hubble users have discarded these sky-photons, as they are interested in the faint discrete objects in Hubble’s images such as stars and galaxies,” said Windhorst. “But these sky-photons contain important information which can be extracted thanks to Hubble’s unique ability to measure faint brightness levels to high precision over its three decades of lifetime.”

A number of graduate and undergraduate students contributed to project SKYSURF, including Rosalia O’Brien, Delondrae Carter and Darby Kramer at ASU, Scott Tompkins at the University of Western Australia, Sarah Caddy at Macquarie University in Australia, and many others.

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Today’s adolescent substances of choice may be harder for adults to detect

Despite advances in technology and availability, one of the best ways for parents and health care providers to prevent or help stop adolescent substance use is still an old-fashioned conversation, according to a new Viewpoint published in the November issue of The Lancet Child & Adolescent Health. The piece, written by a team of University of Rhode Island trainees under Prochaska Endowed Professor Sarah Feldstein Ewing, stresses that relying on detection through informal observation — as parents and providers have commonly done with alcohol and tobacco use — is quickly becoming a thing of the past. The paper provides health care professionals and parents concrete steps for screening, detection and intervention.

The past decade has seen a global surge in adolescent use of e-cigarettes/vaping, cannabis, and prescription opioids not-taken-as-prescribed. This surge has been aided, in some cases, by entirely new methods of substance use and delivery — such as cannabis edibles and vaping — as well as youths’ lower perceptions of harm, and/or greater accessibility. These substances have “invisible symptoms” to adults and, in turn, can be much harder-to-detect by parents, caregivers, and health care providers.

“What is so different today than in past generations is that parents and providers could really rely on what we traditionally think of as obvious signs to tell if kids were using. Did they come home smelling like cigarettes or cannabis? Is there alcohol on their breath? Are they slurring their speech?” said Feldstein Ewing. “While some of these things still work, where we run into trouble today is that, more and more, the substances that kids are using are just not as easy to spot. And, the signs are not as conspicuous as they once were.”

This is especially concerning when it comes to the still-developing adolescent brain. While the ways in which these substances affect the brain are under ongoing investigation, there is evidence to suggest that their use during adolescence may adversely affect long-term neural and behavioral development. Also, because their use can be hard to identify by adults, youth may be more likely to transition from experimentation to heavier, hazardous use in a manner that is often undetected by providers or caregivers until there is a substantial impact on school, work, or their personal or family relationships.

In addition to her position as a professor of psychology within URI’s College of Health Sciences, Feldstein Ewing is a child/adolescent clinician with over two decades experience working in adolescent substance use prevention and treatment.

“Families would come to me for treatment for youth engaged in heavy substance use and say, ‘I didn’t even know my kid was using.’ Parents are having a hard time and now that many states are making cannabis legal for recreational use, I think parents and providers are really feeling at a loss to navigate this,” she said.

The Viewpoint is primarily geared toward adolescent health care providers who are in a unique position to assist in detection as well as facilitating access to treatment services, due to their recurring appointments with young people. But, says Feldstein Ewing, parents and caregivers may also find the recommendations helpful. Opening the lines of communication with young people can provide adolescents a platform in which to discuss current life concerns, including substance use. One straightforward way that parents or caregivers can do this, she says, is by increasing the frequency of family dinners.

“It’s definitely hard today — families are busy with work, school, sports and other activities. But the point is, if that can be a place where you are seeing and connecting with your kids every day, it will be easier to notice small changes in behavior or other patterns. It doesn’t even have to be a dinner, it can also take the form of drives or walks — if you provide a forum to talk about ‘regular stuff’ it will be easier for them and for you to bring these things up.”

Provider use of well-validated substance use screening tools, specific for adolescents, is recommended as part of the framework — as is active listening and the use of open-ended questions. Providers may also be able to communicate things that parents can’t, such as the risks and potential longer-term effects associated with such substances. By the same token, adolescents may be more likely to open up to providers in the patient-provider context. Parents and providers may find that asking about peer use can provide helpful insights while being perceived as less intrusive to young people.

“The most important part of all this is that this is new territory — and that’s OK. The things we have done historically no longer translate well for these new forms of substances, so we need to readjust. Providers and parents often do not feel comfortable discussing topics like substance use because they are not sure what to do if teens say, ‘Yes , we are using’,” said Feldstein Ewing. “But when it comes down to it, even though we often think about teens as spending most of their time with their friends, parents still have the biggest influence on their teen’s behavior. So knowing where they are, who they are hanging out with, and being open to having these sometimes scary conversations on a consistent basis is important. And, providers have a critical role to play in supporting kids and families.”

Feldstein Ewing is Director of URI’s Adolescent Neuroscience Center for Health Resilience, which focuses on adolescent translational approaches, increasing understanding of the links between basic biological mechanisms — like the brain — and effective treatments for reducing adolescent health risk behaviors. Several of Feldstein Ewing’s trainees contributed to the piece, including lead author, Genevieve Dash, M.S., at the University of Missouri; as well as Karen Hudson, M.C.R., at URI; and her URI graduate students Emily Kenyon, Emily Carter, and Diana Ho.

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Without more data, a black hole’s origins can be ‘spun’ in any direction

Clues to a black hole’s origins can be found in the way it spins. This is especially true for binaries, in which two black holes circle close together before merging. The spin and tilt of the respective black holes just before they merge can reveal whether the invisible giants arose from a quiet galactic disk or a more dynamic cluster of stars.

Astronomers are hoping to tease out which of these origin stories is more likely by analyzing the 69 confirmed binaries detected to date. But a new study finds that for now, the current catalog of binaries is not enough to reveal anything fundamental about how black holes form.

In a study appearing in the journal Astronomy and Astrophysics Letters, MIT physicists show that when all the known binaries and their spins are worked into models of black hole formation, the conclusions can look very different, depending on the particular model used to interpret the data.

A black hole’s origins can therefore be “spun” in different ways, depending on a model’s assumptions of how the universe works.

“When you change the model and make it more flexible or make different assumptions, you get a different answer about how black holes formed in the universe,” says study co-author Sylvia Biscoveanu, an MIT graduate student working in the LIGO Laboratory. “We show that people need to be careful because we are not yet at the stage with our data where we can believe what the model tells us.”

The study’s co-authors include Colm Talbot, an MIT postdoc; and Salvatore Vitale, an associate professor of physics and a member of the Kavli Institute of Astrophysics and Space Research at MIT.

A tale of two origins

Black holes in binary systems are thought to arise via one of two paths. The first is through “field binary evolution,” in which two stars evolve together and eventually explode in supernovae, leaving behind two black holes that continue circling in a binary system. In this scenario, the black holes should have relatively aligned spins, as they would have had time — first as stars, then black holes — to pull and tug each other into similar orientations. If a binary’s black holes have roughly the same spin, scientists believe they must have evolved in a relatively quiet environment, such as a galactic disk.

Black hole binaries can also form through “dynamical assembly,” where two black holes evolve separately, each with its own distinct tilt and spin. By some extreme astrophysical processes, the black holes are eventually brought together, close enough to form a binary system. Such a dynamical pairing would likely occur not in a quiet galactic disk, but in a more dense environment, such as a globular cluster, where the interaction of thousands of stars can knock two black holes together. If a binary’s black holes have randomly oriented spins, they likely formed in a globular cluster.

But what fraction of binaries form through one channel versus the other? The answer, astronomers believe, should lie in data, and particularly, measurements of black hole spins.

To date, astronomers have derived the spins of black holes in 69 binaries, which have been discovered by a network of gravitational-wave detectors including LIGO in the U.S., and its Italian counterpart Virgo. Each detector listens for signs of gravitational waves — very subtle reverberations through space-time that are left over from extreme, astrophysical events such as the merging of massive black holes.

With each binary detection, astronomers have estimated the respective black hole’s properties, including their mass and spin. They have worked the spin measurements into a generally accepted model of black hole formation, and found signs that binaries could have both a preferred, aligned spin, as well as random spins. That is, the universe could produce binaries in both galactic disks and globular clusters.

“But we wanted to know, do we have enough data to make this distinction?” Biscoveanu says. “And it turns out, things are messy and uncertain, and it’s harder than it looks.”

Spinning the data

In their new study, the MIT team tested whether the same data would yield the same conclusions when worked into slightly different theoretical models of how black holes form.

The team first reproduced LIGO’s spin measurements in a widely used model of black hole formation. This model assumes that a fraction of binaries in the universe prefer to produce black holes with aligned spins, where the rest of the binaries have random spins. They found that the data appeared to agree with this model’s assumptions and showed a peak where the model predicted there should be more black holes with similar spins.

They then tweaked the model slightly, altering its assumptions such that it predicted a slightly different orientation of preferred black hole spins. When they worked the same data into this tweaked model, they found the data shifted to line up with the new predictions. The data also made similar shifts in 10 other models, each with a different assumption of how black holes prefer to spin.

“Our paper shows that your result depends entirely on how you model your astrophysics, rather than the data itself,” Biscoveanu says.

“We need more data than we thought, if we want to make a claim that is independent of the astrophysical assumptions we make,” Vitale adds.

Just how much more data will astronomers need? Vitale estimates that once the LIGO network starts back up in early 2023, the instruments will detect one new black hole binary every few days. Over the next year, that could add up to hundreds more measurements to add to the data.

“The measurements of the spins we have now are very uncertain,” Vitale says. “But as we build up a lot of them, we can gain better information. Then we can say, no matter the detail of my model, the data always tells me the same story — a story that we could then believe.”

This research was supported in part by the National Science Foundation.

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Curved spacetime in the lab

In a laboratory experiment, researchers from Heidelberg University have succeeded in realising an effective spacetime that can be manipulated. In their research on ultracold quantum gases, they were able to simulate an entire family of curved universes to investigate different cosmological scenarios and compare them with the predictions of a quantum field theoretical model.

According to Einstein’s Theory of Relativity, space and time are inextricably connected. In our Universe, whose curvature is barely measurable, the structure of this spacetime is fixed. In a laboratory experiment, researchers from Heidelberg University have succeeded in realising an effective spacetime that can be manipulated. In their research on ultracold quantum gases, they were able to simulate an entire family of curved universes to investigate different cosmological scenarios and compare them with the predictions of a quantum field theoretical model. The research results were published in Nature.

The emergence of space and time on cosmic time scales from the Big Bang to the present is the subject of current research that can only be based on the observation of our single Universe. The expansion and curvature of space are essential to cosmological models. In a flat space like our current Universe, the shortest distance between two points is always a straight line. “It is conceivable, however, that our Universe was curved in its early phase. Studying the consequences of a curved spacetime is therefore a pressing question in research,” states Prof. Dr Markus Oberthaler, a researcher at the Kirchhoff Institute for Physics at Heidelberg University. With his “Synthetic Quantum Systems” research group, he developed a quantum field simulator for this purpose.

The quantum field simulator created in the lab consists of a cloud of potassium atoms cooled to just a few nanokelvins above absolute zero. This produces a Bose-Einstein condensate — a special quantum mechanical state of the atomic gas that is reached at very cold temperatures. Prof. Oberthaler explains that the Bose-Einstein condensate is a perfect background against which the smallest excitations, i.e. changes in the energy state of the atoms, become visible. The form of the atomic cloud determines the dimensionality and the properties of spacetime on which these excitations ride like waves. In our Universe, there are three dimensions of space as well as a fourth: time.

In the experiment conducted by the Heidelberg physicists, the atoms are trapped in a thin layer. The excitations can therefore only propagate in two spatial directions — the space is two-dimensional. At the same time, the atomic cloud in the remaining two dimensions can be shaped in almost any way, whereby it is also possible to realise curved spacetimes. The interaction between the atoms can be precisely adjusted by a magnetic field, changing the propagation speed of the wavelike excitations on the Bose-Einstein condensate.

“For the waves on the condensate, the propagation speed depends on the density and the interaction of the atoms. This gives us the opportunity to create conditions like those in an expanding universe,” explains Prof. Dr Stefan Flörchinger. The researcher, who previously worked at Heidelberg University and joined the University of Jena at the beginning of this year, developed the quantum field theoretical model used to quantitatively compare the experimental results.

Using the quantum field simulator, cosmic phenomena, such as the production of particles based on the expansion of space, and even the spacetime curvature can be made measurable. “Cosmological problems normally take place on unimaginably large scales. To be able to specifically study them in the lab opens up entirely new possibilities in research by enabling us to experimentally test new theoretical models,” states Celia Viermann, the primary author of the “Nature” article. “Studying the interplay of curved spacetime and quantum mechanical states in the lab will occupy us for some time to come,” says Markus Oberthaler, whose research group is also part of the STRUCTURES Cluster of Excellence at Ruperto Carola.

The work was conducted as part of Collaborative Research Centre 1225, “Isolated Quantum Systems and Universality in Extreme Conditions” (ISOQUANT), of Heidelberg University.

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Astronomers report most distant known galaxies, detected and confirmed

An international team of astronomers has discovered the earliest and most distant galaxies confirmed to date using data from the James Webb Space Telescope (JWST). The telescope captured light emitted by these galaxies more than 13.4 billion years ago, which means the galaxies date back to less than 400 million years after the Big Bang, when the universe was only 2% of its current age.

Initial observations from JWST yielded several candidate galaxies at extreme distances, as had earlier observations with the Hubble Space Telescope. Now, four of these targets have been confirmed by obtaining long spectroscopic observations, which not only provide secure measurements of their distances, but also allow astronomers to characterize the physical properties of the galaxies.

“We’ve discovered galaxies at fantastically early times in the distant universe,” said Brant Robertson, professor of astronomy and astrophysics at UC Santa Cruz. “With JWST, for the first time we can now find such distant galaxies and then confirm spectroscopically that they really are that far away.”

Astronomers measure the distance to a galaxy by determining its redshift. Due to the expansion of the universe, distant objects appear to be receding from us and their light is stretched to longer, redder wavelengths by the Doppler effect. Photometric techniques based on images captured through different filters can provide redshift estimates, but definitive measurements require spectroscopy, which separates the light from an object into its component wavelengths.

The new findings focus on four galaxies with redshifts higher than 10. Two galaxies initially observed by Hubble now have confirmed redshifts of 10.38 and 11.58. The two most distant galaxies, both detected in JWST images, have redshifts of 13.20 and 12.63, making them the most distant galaxies confirmed by spectroscopy to date. A redshift of 13.2 corresponds to about 13.5 billion years ago.

“These are well beyond what we could have imagined finding before JWST,” Robertson said. “At redshift 13, the universe is only about 325 million years old.”

Robertson and Emma Curtis-Lake from the University of Hertfordshire (U.K.) will be presenting the new findings on December 12 at a Space Telescope Science Institute (STScI) conference in Baltimore on “First Science Results from JWST.” They are the lead authors of two papers on the results that have not yet been through the peer-review process.

The observations result from a collaboration of scientists who led the development of two of the instruments onboard Webb, the Near-Infrared Camera (NIRCam) and the Near-Infrared Spectrograph (NIRSpec). The investigation of the faintest and earliest galaxies was the leading motivation in the concepts for these instruments. In 2015, the instrument teams joined together to propose the JWST Advanced Deep Extragalactic Survey (JADES), an ambitious program that has been allocated just over one month of the telescope’s time and is designed to provide a view of the early universe unprecedented in both depth and detail. JADES is an international collaboration of more than eighty astronomers from ten countries.

“These results are the culmination of why the NIRCam and NIRSpec teams joined together to execute this observing program,” said Marcia Rieke, NIRCam principal investigator at the University of Arizona.

The JADES program began with NIRCam, using over 10 days of mission time to observe a small patch of sky in and around the Hubble Ultra Deep Field. Astronomers have been studying this region for over 20 years with nearly all large telescopes. The JADES team observed the field in nine different infrared wavelength ranges, capturing exquisite images that reveal nearly 100,000 distant galaxies, each billions of light years away.

The team then used the NIRSpec spectrograph for a single three-day observation period to collect the light from 250 faint galaxies. This yielded precise redshift measurements and revealed the properties of the gas and stars in these galaxies.

“With these measurements, we can know the intrinsic brightness of the galaxies and figure out how many stars they have,” Robertson said. “Now we can start to really pick apart how galaxies are put together over time.”

Coauthor Sandro Tacchella from the University of Cambridge in the United Kingdom added, “It is hard to understand galaxies without understanding the initial periods of their development. Much as with humans, so much of what happens later depends on the impact of these early generations of stars. So many questions about galaxies have been waiting for the transformative opportunity of Webb, and we’re thrilled to be able to play a part in revealing this story.”

According to Robertson, star formation in these early galaxies would have begun about 100 million years earlier than the age at which they were observed, pushing the formation of the earliest stars back to around 225 million years after the Big Bang.

“We are seeing evidence of star formation about as early as we could expect based on our models of galaxy formation,” he said.

Other teams have identified candidate galaxies at even higher redshifts based on photometric analyses of JWST images, but these have yet to be confirmed by spectroscopy. JADES will continue in 2023 with a detailed study of another field, this one centered on the iconic Hubble Deep Field, and then a return to the Ultra Deep Field for another round of deep imaging and spectroscopy. Many more candidates in the field await spectroscopic investigation, with hundreds of hours of additional time already approved.

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France makes condoms free for 18 to 25 year olds

The new health measure follows an increase in sexually transmitted infections in France.

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Scientist mimic nature to make nano particle metallic snowflakes

Scientists in New Zealand and Australia working at the level of atoms created something unexpected: tiny metallic snowflakes. Why’s that significant? Because coaxing individual atoms to cooperate in desired ways is leading to a revolution in engineering and technology via nanomaterials (And creating snowflakes is cool.) Nanoscale structures (a nanometre is one billionth of a metre) can aid electronic manufacturing, make materials stronger yet lighter, or aid environmental clean-ups by binding to toxins.

To create metallic nanocrystals, New Zealand and Australian scientists have been experimenting with gallium, a soft, silvery metal which is used in semiconductors and, unusually, liquifies at just above room temperature. Their results were just reported in the journal Science.

Professor Nicola Gaston and research fellow Dr Steph Lambie, both of Waipapa Taumata Rau, University of Auckland, and Dr Krista Steenbergen of Te Herenga Waka, Victoria University of Wellington, collaborated with colleagues in Australia led by Professor Kourosh Kalantar-Zadeh at the University of New South Wales.

The Australian team worked in the lab with nickel, copper, zinc, tin, platinum, bismuth, silver and aluminium, growing metal crystals in a liquid solvent of gallium. Metals were dissolved in gallium at high temperatures. Once cooled, the metallic crystals emerged while the gallium remained liquid. The New Zealand team, part of the MacDiarmid Institute for Advanced Materials and Nanotechnology, a national Centre of Research Excellence, carried out simulations of molecular dynamics to explain why differently shaped crystals emerge from different metals. (The government’s Marsden Fund supported the research.)

“What we are learning is that the structure of the liquid gallium is very important,” says Gaston. “That’s novel because we usually think of liquids as lacking structure or being only randomly structured.” Interactions between the atomistic structures of the different metals and the liquid gallium cause differently shaped crystals to emerge, the scientists showed.

The crystals included cubes, rods, hexagonal plates and the zinc snowflake shapes. The six-branched symmetry of zinc, with each atom surrounded by six neighbours at equivalent distances, accounts for the snowflake design. “In contrast to top-down approaches to forming nanostructure — by cutting away material — this bottom-up approaches relies on atoms self-assembling,” says Gaston. “This is how nature makes nanoparticles, and is both less wasteful and much more precise than top-down methods.” She says the research has opened up a new, unexplored pathway for metallic nanostructures. “There’s also something very cool in creating a metallic snowflake!”

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Materials provided by University of Auckland. Note: Content may be edited for style and length.

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