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In this gorgeous essay for Vittles, the poet Seán Hewitt recalls weekend nature walks in England and his grandfather’s lessons on the wonders of foraged food. Inspired by the abundant hawthorns in Dublin’s Phoenix Park, Hewitt writes about making his own hawthorn gin.
When the hawthorns were all done and the gin was in the jar, I put it into the cupboard, then checked on it every week, turning it, watching the colours darken. Now I’ve learned to leave it in peace, and I don’t turn it that often anymore. I just bide my time until December when, on some foggy, cold evening – when it feels like winter has begun – I take it out of the cupboard.
The main difference between sloe and hawthorn gin is that, where sloe gin is fruity and sweet and mixes well with tonic or soda, hawthorn gin is like a dark sherry, perfect for winter. It has a velvety texture, a rich smoothness. I also like that, unlike sloe gin, you can’t buy it anywhere, so hawthorn gin becomes a secret, shared thing between friends, a preservation of summer pulled into winter.
I’m turning 40 in a few months and trying not to think too much of it, but I am getting my bearings a bit.
Yesterday Elisa Gabbert tweeted, “I think I liked magazines more as a kid because the writing was by people older and wiser than me, with different generational interests. Now it’s just, like, writing by my friends, or people who could be? I’m supposed to pay for this? Lol”
I had a good laugh at this. It made me think that a good move at this age might be to start reading the NYTimes for Kids (which I already do) or Teen Vogue or AARP.
This would be the publication equivalent to Kevin Kelly’s advice, “When you are young, have friends who are older; when you are old, have friends who are younger.”
I do feel kind of lucky right now, to be in the middle: I have my kids and their friends for youth spies and for an elder perspective, I ride bikes twice a week with a 75-year-old who is still mad that Dylan went electric.
Everything changes, always, but I’m enjoying this age at the moment.
Thought of this one after witnessing a grown man have a tantrum in public. There but for the grace…
At age 90, Jane Miller relates her ongoing battle with a self that wants to “indulge my lurking wish to spend longer in bed in the morning reading the Guardian and listening to the Today programme than I already do,” and the one that obsessively logs steps and reads classics in their original Russian, to make the most of her physical and mental abilities.
I am freer than I’ve ever been, yet I quite often feel edged out, and it’s clear that I have become actually and metaphorically deaf to significant contemporary sounds. My spectator’s view of it all doesn’t fail to remind me that other people are not so lucky or so detached, that some of them are sad beyond hope, that there are young people who don’t want to stay alive and people who worry to distraction and despair or who suffer all kinds of untreatable pain. I became an adult just after the end of the Second World War, and I think of the 1950s, so often described by younger generations as bleak and impoverished, as a time of idealism and optimism. I find it difficult to detect that sort of faith in the future now, though I hope against hope that it’s there in some form I’m simply too old to recognise.
A new method uses nuclear magnetic resonance (NMR) spectroscopy to detect food adulteration, specifically whether fillers like vegetable oil have been added to food products.
The scientists were motivated by a need to help regulatory agencies like the US Food and Drug Administration (FDA) with detection of adulterated food products that are products in which certain ingredients are missing or replaced.
“Food adulteration leads to a product that is cheaper to produce but is sold as the original product,” says scientist Colleen Ray of the University of Missouri department of chemistry. “This results in consumers buying a product that is not what they expected and is often inferior to the unadulterated version. Therefore, we wanted to explore the authenticity of these products.”
Ray compares the use of NMR spectroscopy with MRI.
“When medical professionals use an MRI to gauge the severity of a torn ligament or to follow a cancerous tumor, they are just using NMR spectroscopy,” she says. “The main difference is that they create pictures from the data, and we use the data to figure out the structure of molecules.”
NMR spectroscopy uses a magnet and radio waves to determine the content and purity of different substances and has been used before with other food products like honey, olive oil, and wine, says C. Michael Greenlief, director of the University of Missouri Proteomics Center and Nuclear Magnetic Resonance Facility and corresponding author of the study.
“The analysis of food products with NMR spectroscopy is a powerful tool for the detection of adulteration,” says Greenlief, a professor of chemistry. “It is ideal for analyses of this type due to a high sample throughout, the ability to discriminate based on structural differences of metabolites with similar masses, and the ability to examine samples in either their native state or with little sample preparation.”
In the study, the scientists created and tested a method to identify vegetable oil adulterants in hard cheese products. They discovered 29% of 52 samples of various non-refrigerated grated parmesan cheese were adulterated with palm oil, a type of vegetable oil. They also note the labels of the adulterated samples did not declare palm oil as an ingredient on their labels.
“Genuine cheeses were found to have a very consistent lipid profile from sample to sample, improving the power of this approach to detect vegetable oil adulteration,” Ray says. “Palm oil itself is a clever adulterant owing to its semi-solid state at room temperature, similar color to cheese, and low price compared to cheese. However, this study is strictly limited to the lipid profile of these products, and no attempts were made to quantify any fillers aside from palm oil.”
The FDA characterizes intentional food adulteration done for financial reasons as “economically motivated adulteration” or “food fraud.” A scientist at the FDA has also expressed interest in learning more about the team’s process to help detect adulteration in food products.
The work appears in the journal Molecules. Other coauthors are from the University of Missouri and Sweetwater Science Laboratories.
Source: University of Missouri
The post New method detects food fillers appeared first on Futurity.
New research shows how the atoms in perovskites move in response to light.
The breakthrough in visualization supports the researchers’ efforts to squeeze every possible drop of utility out of perovskite-based materials, including solar cells, a long-standing project that only recently yielded an advance to make the devices far more durable.
The study in Nature Physics details the first direct measurement of structural dynamics under light-induced excitation in 2D perovskites. Perovskites are layered materials that have well-ordered crystal lattices. They are highly efficient harvesters of light that are being explored for use as solar cells, photodetectors, photocatalysts, light-emitting diodes, quantum emitters, and more.
“The next frontier in light-to-energy conversion devices is harvesting hot carriers,” Aditya Mohite, a corresponding author of the study. “Studies have shown that hot carriers in perovskite can live up to 10-100 times longer than in classical semiconductors. However, the mechanisms and design principles for the energy transfer and how they interact with the lattice are not understood.”
Hot carriers are short-lived, high-energy charge carriers, either electrons for negative charges or electron “holes” for positive charges, and having the ability to harvest their energy would allow light-harvesting devices to “surpass thermodynamic efficiency,” says Mohite, an associate professor of chemical and biomolecular engineering in Rice University’s George R. Brown School of Engineering.
Mohite and three members of his research group, senior scientist Jean-Christophe Blancon and graduate students Hao Zhang and Wenbin Li, worked with colleagues at the SLAC National Accelerator Laboratory to see how atoms in a perovskite lattice rearranged themselves when a hot carrier was created in their midst. They visualized lattice reorganization in real time using ultrafast electron diffraction.
“Whenever you expose these soft semiconductors to stimuli like electric fields, interesting things happen,” Mohite says. “When you generate electrons and holes, they tend to couple to the lattice in unusual and really strong ways, which is not the case for classical materials and semiconductors.
“So there was a fundamental physics question,” he says. “Can we visualize these interactions? Can we see how the structure is actually responding at very fast timescales as you put light onto this material?”
The answer was yes, but only with a strong input. SLAC’s mega-electron-volt ultrafast electron diffraction (MeV-UED) facility is one of the few places in the world with pulsed lasers capable of creating the electron-hole plasma in perovskites that was needed to reveal how the lattice structure changed in less than a billionth of a second in response to a hot carrier.
“The way this experiment works is that you shoot a laser through the material and then you send an electron beam that goes past it at a very short time delay,” Mohite explains. “You start to see exactly what you would in a TEM (transmission electron microscope) image. With the high-energy electrons at SLAC, you can see diffraction patterns from thicker samples, and that allows you to monitor what happens to those electrons and holes and how they interact with the lattice.”
The experiments at SLAC produced before-and-after diffraction patterns that Mohite’s team interpreted to show how the lattice changed. They found that after the lattice was excited by light, it relaxed and literally straightened up in as little as one picosecond, or one-trillionth of a second.
Zhang says, “There’s a subtle tilting of the perovskite octahedra, which triggers this transient lattice reorganization towards a higher symmetric phase.”
By demonstrating that a perovskite lattice can suddenly become less distorted in response to light, the research showed it should be possible to tune how perovskite lattices interact with light, and it suggested a way to accomplish the tuning.
Li says, “This effect is very dependent on the type of structure and type of organic spacer cation.”
There are many recipes for making perovskites, but all contain organic cations, an ingredient that acts as a spacer between the materials’ semiconducting layers. By substituting or subtly changing organic cations, researchers could tailor lattice rigidity, dialing it up or down to alter how the material responds to light, Li says.
Mohite says the experiments also show that tuning a perovskite’s lattice alters its heat-transfer properties.
“What is generally expected is that when you excite electrons at a very high energy level, they lose their energy to the lattice,” he says. “Some of that energy is converted to whatever process you want, but a lot of it is lost as heat, which shows in the diffraction pattern as a loss in intensity.
“The lattice is getting more energy from thermal energy,” Mohite says. “That’s the classical effect, which is expected, and is well-known as the Debye-Waller factor. But because we can now know exactly what’s happening in every direction of the crystal lattice, we see the lattice starts to get more crystalline or ordered. And that’s totally counterintuitive.”
A better understanding of how excited perovskites handle heat is a bonus of the research, he says.
“As we make devices smaller and smaller, one of the biggest challenges from a microelectronics perspective is heat management,” Mohite says. “Understanding this heat generation and how it’s being transported through materials is important.
“When people talk about stacking devices, they need to be able to extract heat very fast,” he says. “As we move to new technologies that consume less power and generate less heat, these types of measurements will allow us to directly probe how heat is flowing.”
The research had support from the Department of Energy, the Office of Naval Research, the Robert A. Welch Foundation, and the Academic Institute of France.
Source: Rice University
The post Team sees light make atoms ‘dance’ in perovskites appeared first on Futurity.
Enlarge (credit: NurPhoto / Contributor | NurPhoto)
New details have been revealed through recently unsealed Cook County court documents, showing how federal investigators in 2020 gained access to encrypted Telegram messages to uncover “a cross-country network of people sexually exploiting children.”
The Chicago Sun-Times reported that Homeland Security Investigations (HSI) agents based in Arizona launched “Operation Swipe Left” in 2020 to investigate claims of kidnapping, livestreaming child abuse, and production and distribution of child sexual abuse materials (CSAM). That investigation led to criminal charges filed against at least 17 people. The majority of defendants were living in Arizona, but others charged were residents of Illinois, Wisconsin, Washington, DC, California, and South Africa. Ten children were rescued, including four children actively suffering abuse at the time of the rescue. The youngest victim identified was 6 months old, and the oldest was 17 years old.
Telegram became a preferred tool for defendants in this investigation, many of whom believed that police could never access their encrypted messages. At least one federal prosecutor told a judge that authorities never would have gained access; however, one of the defendants, Adam Hageman, “fully cooperated” with investigators and granted access through his account to offending Telegram groups.
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