Lead investigator MaryAnne Drake, PhD, of the North Carolina State University Department of Food, Bioprocessing and Nutrition Sciences, Raleigh, NC, USA, explained that “milk is more susceptible to packaging-related off-flavors than many other beverages because of its mild, delicate taste.” Besides light oxidation, “milk’s taste can be impacted by the exchange of the packaging’s compounds into the milk and by the packaging absorbing food flavors and aromas from the surrounding refrigeration environment.”

To quantify the flavor impacts of packaging, the researchers examined pasteurized whole and skim milk stored in six half pint containers: paperboard cartons, three plastic jugs (made from different plastics), a plastic bag, and glass as a control. The milk was stored in total darkness to control for light oxidation and kept cold at 4°C (39°F).

The samples were tested on the day of first processing, then again at 5, 10, and 15 days after. A trained panel examined the sensory properties of each sample, and the research team conducted a volatile compound analysis to understand how the packaging was intermingling with the milk. Finally, the samples underwent a blind consumer taste test on day 10 to see whether tasters could tell any difference between milk stored in the paperboard carton or the plastic jug compared with milk packaged in glass.

The results showed that package type doesinfluence milk flavor, and skim milk is more susceptible to flavor impacts than whole milk. Of the different packaging types, paperboard cartons and the plastic bag preserved milk freshness the least due to the paperboard’s absorption of milk flavor and the transfer of paperboard flavor into the milk. Milk packaged in paperboard cartons, in fact, showed distinct off-flavors as well as the presence of compounds from the paperboard. The final results show that, while glass remains an ideal container for preserving milk flavor, plastic containers provide additional benefits while also maintaining freshness in the absence of light exposure.

Paperboard cartons are the most widely used packaging type for school meal programs in the United States, so these findings are especially relevant for the consideration of how young children consume and enjoy milk.

“These findings suggest that industry and policymakers might want to consider seeking new package alternatives for milk served during school meals,” said Drake. Over time, the consequences of using milk packaging that contributes significant off-flavors may affect how young children perceive milk in both childhood and adulthood.

Methane is the second most important greenhouse gas after carbon dioxide, contributing about 1 degree Fahrenheit of present-day global warming relative to pre-industrial times. One major source of methane to the atmosphere is the extraction and transport of oil and gas. Countries are obligated to report their greenhouse gas emissions to international bodies such as the United Nations Framework Convention on Climate Change, but recent studies suggest that the current methods for calculating methane emissions rely on outdated and incomplete information and may not accurately represent actual emissions.

A recent study from researchers at Princeton University and Colorado State University finds that the current method for estimating methane emissions from offshore oil and gas production in the United Kingdom systematically and severely underestimates emissions. The study finds that as much as five times more methane is being emitted from oil and gas production in the UK than what the government has reported. The researchers reached this conclusion by critically evaluating the UK’s current method of calculating methane emissions, suggesting alternative, peer-review based methods and generating revised emission estimates.

Sincemany other countries use similar methodologies to calculate methane emissions from oil and gas production, this severe underestimation is likely not confined to the UK alone.

“It is critical to know when, where and how much methane is emitted from each of its sources in order to prioritize emission reductions,” said Denise Mauzerall, a co-author and core faculty member of the Center for Policy Research on Energy and the Environment at Princeton University. “We hope our work will facilitate improved emission estimates and reductions not only from the UK but also from other countries producing methane from oil and gas extraction,” Mauzerall said.

Due to its climate and indirect health impacts (methane is a precursor for ozone which is an air pollutant that damages human health and crops), methane mitigation has recently become a global policy priority. Its relatively short lifetime of about 12 years and high heat trapping ability per molecule makes reducing methane emissions among the most effective ways to slow the rate of climate warming. As a result, in 2021 countries signed the Global Methane Pledge, committing to reduce methane emissions by at least 30% of 2020 levels by 2030. To track progress, countries compile national emissions data into inventories, such as the UK’s National Atmospheric Emissions Inventory (NAEI), which are then reported to international monitoring bodies.

This study focuses on methane leakage associated with discovery, extraction, and production of oil and natural gas. These methane emissions are typically calculated by multiplying the activity level of various processes – namely venting, flaring, processing and combustion activities on production platforms, offshore oil loading, and gas transfer by high-pressure pipelines – by “emission factors,” which are standard estimates of the methane emissions associated with each activity.

The researchers found that the emissions factors used in the UK’s reporting are either outdated, rely on unpublished or publicly unavailable industry research, or use generic values recommended by the IPCC. Furthermore, these emission factors are usually “static,” meaning that they are not sensitive to factors such as environmental conditions and management practices which could affect emissions from various processes. In addition, leakage can occur when the off-shore rigs are idle – an “activity” that does not currently have an associated emission factor.

Noting these shortcomings, the researchers updated and revised estimation techniques for each process, and, wherever possible, used dynamic rather than static emission factor formulations that account for varying environmental conditions. They also incorporated direct boat-based measurements of methane concentrations around offshore gas platforms in the North Sea collected in summer 2017, documented in a study also led by the authors. These updates resulted in a total methane emission estimate more than five times larger than reported emissions.

“Methane emissions from offshore facilities are currently largely uncertain, and because sources on facilities only emit for a short time period, using direct survey methods such as satellite or drones will probably only capture about 25% of the actual emissions,” said Stuart Riddick, lead author and research scientist at Colorado State University. “To generate representative baseline emissions across the sector, we need to work with industry to develop practical, effective, and collaborative measurement strategies,” Riddick said.

Previous research has shown that reducing leakage across the oil and natural gas supply chain can advance climate and air quality goals while also being economically profitable – a win-win opportunity for industry and climate.

This study adds to a growing base of literature finding that current measurements of anthropogenic methane emission inventories are too low. With the world’s first “global stocktake” on progress implementing the Paris Agreement concluding in 2023, the researchers argue that improved measurement of emissions deserves urgent attention.

“We are hopeful that our work will facilitate more accurate emission inventory development and lead to critically important reductions of methane leakage – a win for both industry and the environment,” Mauzerall said.

These technologies will be transformative to a broad range of industries and research efforts: from the security of information transfer, through the search for materials and chemicals with novel properties, to measurements of fundamental physical phenomena requiring precise time synchronisation among the sensors.

Spin-photon interfaces are elementary building blocks for quantum networks that allow converting stationary quantum information (such as the quantum state of an ion or a solid-state spin qubit) into light, namely photons, that can be distributed over large distances. A major challenge is to find an interface that is both good at storing quantum information and efficient at converting it into light. Optically active semiconductor quantum dots are the most efficient spin-photon interface known to date but extending their storage time beyond a few microseconds has puzzled physicists in spite of decade-long research efforts. Now, researchers at the University of Cambridge, the University of Linz and the University of Sheffield have shown that there is a simple material’s solution to this problem that improves the storage of quantum information beyond hundred microseconds.

Quantum Dots are crystalline structures made out of many thousands of atoms. Each of these atoms’ nuclei has a magnetic dipole moment that couples to the quantum dot electron and can cause the loss of quantum information stored in the electron qubit. The research team’s finding, reported in Nature Nanotechnology, is that in a device constructed with semiconductor materials that have the same lattice parameter, the nuclei ‘felt’ the same environment and behaved in unison. As a result, it is now possible to filter out this nuclear noise and achieve a near two-order magnitude improvement in storage time.

“This is a completely new regime for optically active quantum dots where we can switch off the interaction with nuclei and refocus the electron spin over and over again to keep its quantum state alive,” said Claire Le Gall from Cambridge’s Cavendish Laboratory, who led the project. “We demonstrated hundreds of microseconds in our work, but really, now we are in this regime, we know that much longer coherence times are within reach. For spins in quantum dots, short coherence times were the biggest roadblock to applications, and this finding offers a clear and simple solution to that.”

While exploring the hundred-microsecond timescales for the first time, the researchers were pleasantly surprised to find that the electron only sees noise from the nuclei as opposed to, say, electrical noise in the device. This is really a great position to be in because the nuclear ensemble is an isolated quantum system, and the coherent electron will be a gateway to quantum phenomena in large nuclear spin ensemble.

Another thing that surprised the researchers was the ‘sound’ that was picked up from the nuclei. It was not quite as harmonious as was initially anticipated, and there is room for further improvement in the system’s quantum coherence through further material engineering.

“When we started working with the lattice-matched material system employed in this work, getting quantum dots with well-defined properties and good optical quality wasn’t easy” — says Armando Rastelli, co-author of this paper at the University of Linz. “It is very rewarding to see that an initially curiosity-driven research line on a rather ´exotic´ system and the perseverance of skilled team members Santanu Manna and Saimon Covre da Silva led to the devices at the basis of these spectacular results. Now we know what our nanostructures are good for, and we are thrilled by the perspective of further engineering their properties together with our collaborators.”

“One of the most exciting things about this research is taming a complex quantum system: a hundred thousand nuclei coupling strongly to a well-controlled electron spin,” explains Cavendish PhD student, Leon Zaporski — the first author of the paper. “Most researchers approach the problem of isolating qubit from the noise by removing all the interactions. Their qubits become a bit like sedated Schrödinger’s cats, that can barely react to anyone pulling on their tail. Our ‘cat’ is on strong stimulants, which — in practice — means we can have more fun with it.”

“Quantum dots now combine high photonic quantum efficiency with long spin coherence times” explains Professor Mete Atatüre, co-author of this paper. “In the near future, we envisage these devices to enable the creation of entangled light states for all-photonic quantum computing and allow foundational quantum control experiments of the nuclear spin ensemble.”

The study, published in the journal Brain, supports the idea that components in the human blood can modulate the formation of new brain cells, a process termed neurogenesis. Neurogenesis occurs in an important part of the brain called the hippocampus that is involved in learning and memory.

While Alzheimer’s disease affects the formation of new brain cells in the hippocampus during the early stages of the disease, previous studies have only been able to study neurogenesis in its later stages through autopsies.

To understand the early changes, researchers collected blood samples over several years from 56 individuals with Mild Cognitive Impairment (MCI), a condition where someone will begin to experience a worsening of their memory or cognitive ability. While not everyone experiencing MCI goes on to develop Alzheimer’s disease, those with the condition progress to a diagnosis at a much higher rate than the wider population. Of the 56 participants in the study, 36 went on to receive a diagnosis of Alzheimer’s disease.

Dr Aleksandra Maruszak, one of the study’s joint first authors from King’s IoPPN explains, “In our study, we treated brain cells with blood taken from people with MCI, exploring how those cells changed in response to blood as Alzheimer’s disease progressed.”

In studying how blood affected the brain cells, the researchers made several key discoveries. The blood samples collected from participants over the years who subsequently deterioratedand developed Alzheimer’s disease promoted a decrease in cell growth and division and an increase in apoptotic cell death (the process by which cells are programmed to die). However, the researchers noted that these samples also increased the conversion of immature brain cells to hippocampal neurons.

While the underlying reasons for the increased neurogenesis remain unclear, the researchers theorise that it may be an early compensating mechanism for the neurodegeneration (loss of brain cells) experienced by those developing Alzheimer’s disease.

Professor Sandrine Thuret, the study’s lead author from King’s IoPPN said, “Previous studies have shown that blood from young mice can have a rejuvenating effect on the cognition of older mice by improving hippocampal neurogenesis. This gave us the idea of modelling the process of neurogenesis in a dish using human brain cells and human blood. In our study, we aimed to use this model to understand the process of neurogenesis and to use changes in this process to predict Alzheimer’s disease and found the first evidence in humans that the body’s circulatory system can have an effect on the brain’s ability to form new cells.”

When the researchers used only the blood samples collected furthest away from when the participants were diagnosed with Alzheimer’s disease, they found that the changes in neurogenesis occurred 3.5 years prior to a clinical diagnosis.

Dr Edina Silajdži?, the study’s joint first author added, “Our findings are extremely important, potentially allowing us to predict onset of Alzheimer’s early in a non-invasive fashion. This could complement other blood-based biomarkers that reflect the classical signs of the disease, such as the accumulation of amyloid and tau (the ‘flagship’ proteins of Alzheimer’s disease).”

Dr Hyunah Lee, the study’s joint first author said, “It is now essential to validate these findings in a bigger and more diverse group of people. We are excited about the potential applications of the blood-based test we used. For example, it can help stratify individuals with memory problems for a clinical trial of disease-modifying drugs for Alzheimer’s.”

The researchers say that these findings could present an opportunity to further understand the changes the brain goes through at the earliest stages of Alzheimer’s disease.

This study was possible thanks to funding from the John and Lucille van Geest Foundation, the Medical Research Council UK, the Cohen Charitable Trust, the Galen and Hilary Weston Foundation and the Rhodes Trust.

Astronomers using the Subaru Telescope and the Canada-France-Hawaii Telescope found a tail of stars stretching 200,000 light-years out away from a galaxy known as F8D1. This galaxy is a member of the M81 group located 12 million light-years away on the boundary between the constellations Ursa Major and Camelopardalis. F8D1 is one of the closest examples of an “ultra-diffuse” galaxy. The origin of these enigmatic galaxies has puzzled astronomers for several decades: are they born this diffuse or does some later event cause them to puff up in size?

The discovery of a huge tidal tail from F8D1 is compelling evidence that the galaxy has been strongly shaped by events in the past billion years. This is the first time that such a stellar stream has been discovered in a UDG. The team suggests F8D1 was disrupted by a recent close passage to the massive spiral M81, the dominant member of the group containing F8D1.

Since F8D1 lies at the edge of the survey area, only one tidal arm can be seen, extending to the northeast. The team will now search to see if there is a counterpart stream to the southwest.

If you’ve picked up seaweed on the beach, waded through fronds in a stream or cleaned out a grimy, green fish tank, then you’ll know what algae is. These diverse aquatic organisms thrive on water, light and nutrients and come in all sorts of shapes, colors and sizes. Microalgae are an ultrasmall type of algae which are invisible to the human eye, but a vital part of the Earth’s ecosystem, forming the basis for all aquatic food chains. They have attracted particular attention from researchers and businesses for their ability to capture carbon dioxide, their use as a biofuel, as an alternative source of protein, and more. There are tens of thousands of types of microalgae, which continue to thrive in unexpected places.

“We were very surprised to discover a new species of microalgae in just a regular home aquarium,” said Professor Sachihiro Matsunaga from the Graduate School of Frontier Sciences. “Alga were taken from the water and cultured one by one. The DNA of the alga was fluorescently stained and microscopically observed to find the one with the least amount of DNA per cell. We then sequenced the DNA of that alga and compared it to the DNA of other algae. The results did not match the DNA of any previously reported algae, indicating that it was a new species, and we named it Medakamo hakoo (M. hakoo).”

Microalgae are made up of relatively few genes, and this uncomplicated form makes them useful for researchers trying to identify what roles different genes play and how they could be used. Of the tens of thousands of known microalgae, many remain uncharacterized. Thanks to this latest study, we now know that not only is this a new species, but it also has the smallest known genome of any freshwater algae, as well as other useful qualities.

“M. hakoo contains only one mitochondrion (for producing energy) and one chloroplast (which contains chlorophyll and creates food through photosynthesis), whereas normal plant cells contain multiple mitochondria and chloroplasts. This indicates that it is a green alga with an extremely simple cell structure,” explained Matsunaga. “From our research, we have also speculated that it has an unprecedented DNA structure and a new gene regulatory system. Its cell cycle is also strongly synchronized with the day and night cycle, which is key to effective, stable bioproduction. Due to these inherent qualities and extremely small size, M. hakoo can be effectively cultured at high cell density, making it possible to mass produce substances such as highly functional foods, cosmetics and bio-fuel at a low cost.”

The researchers plan to continue to explore the potential applications for M. hakoo, both in the lab and the wider world. “Aquatic green algae are the originating organisms of today’s land plants. Thanks to this research, we can better understand the minimum number of genes required for an organism to evolve and thrive in diverse environments, which we will continue to study,” said Matsunaga. “In the future, I would like to find ways to collaborate and create useful substances from the mass cultivation of M. hakoo.”

“We showed that the eruption consisted of two distinct sequences of events, some of which occurred quasi-periodically in the first sequence. It will be worthwhile to investigate the mechanisms involved in such eruption cycles further,” says seismologist and geophysicist Yoshizawa.

The volcano generated seismic, tsunami and atmospheric waves that were recorded worldwide. Recent studies have estimated that it was one of the most energetic eruptions recorded by modern instruments.

“Eruption episodes are difficult to analyse fully from seismic surface waves, but we have teased out more details using what are called teleseismic-P waves,” says PhD student Tarumi. These are seismic waves that have travelled through the planet to locations distant from the eruption site. In this case, the team used seismic data collected from sites as far as at a 93-degree angle around the circumference of the planet.

The team’s “back-projection” analysis successfully detected the locations and timing of multiple explosions, even though P-waves from each eruption overlapped and were masked by other seismic signals and noises.

The back-projection technique reverses the transmission of seismic signals to reveal details of a potential source that radiated seismic waves. It was originally developed and applied for imaging the source processes of large earthquakes, but is now proving equally applicable to large scale volcanic events.

The results revealed that the sequence of eruptions occurred in two main parts. The first sequence began at 04:02 UTC on January 15, then escalated into major explosions at 04:15 UTC and 200 to 300 seconds after. The entire sequence lasted at least until 04:35 UTC. A second sequence of eruptions began about four hours later and continued from six to seven minutes, including a massive eruption at 08:31. Satellite imagery recorded the resulting dramatic ash cloud from the first eruption sequence, but until now the precise details of the underwater events have remained elusive.

One interesting finding was that significant explosive eruptions intermittently occurred at 270 to 280 second intervals, a frequency suggesting a resonance effect with the atmosphere and the Earth. “This apparent agreement of the eruption cycle and the atmospheric resonant oscillation with the Earth could be coincidental, but it certainly deserves further exploration,” Yoshizawa concludes.