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Knowing what species live in which parts of the world is critical to many fields of study, such as conservation biology and environmental monitoring. This is also how we can identify present or potential invasive and non-native pest species. Furthermore, summarizing what species are known to inhabit a given area is essential for the discovery of new species that have not yet been known to science.

For less well-studied groups and regions, distributional species checklists are often not available. Therefore, a series of such checklists is being published in the open-access, peer-reviewed Journal of Hymenoptera Research, in order to address the issue for a group of organisms that, despite its size and diversity, is still poorly known: the insect order Hymenoptera, which includes ants, bees and wasps. The surveyed area spreads across northern North America, which comprises Canada, Alaska (U.S.) and Greenland (Denmark), and occupies about 9.3% of the world's total land mass.

The last distributional survey of Hymenoptera in North America was published in 1979, where about 6000 described species were recorded from Canada and 600 from Alaska. The current survey lists 8933 species in Canada and 1513 in Alaska, marking an increase of 49% and 152%, respectively. A total of 9250 described species are recorded from northern North America. Considering that there are approximately 154,000 described species of Hymenoptera, northern North America has about 6% of the current world total.

Highlights of the series will include updated distributions of over 900 species of bees, which will provide valuable insight into native pollinators at a time when honey bees are in decline. Nearly 230 species of ants and over 100 species of vespid wasps (hornets and yellow jackets) are recorded, including pest species such as the widespread pharaoh ant and the newly invasive Asian giant hornet in British Columbia.

By far, the majority of species of Hymenoptera found in northern North America and the world are parasitoids, which develop on or in other invertebrate hosts and are therefore of great interest to the biological control of pests. Of the 9250 species recorded, more than three-quarters (over 7150 species) are parasitoids. These distributional lists provide essential baseline information required prior to undertaking studies to introduce biological control agents of invasive pests that may have escaped their native, natural enemies when they arrived in North America.

The topical collection "Checklists of the Hymenoptera of Canada, Alaska and Greenland" is to contain a total of eleven papers, where the introduction and the first two checklists: of sawflies (758 species) and one of the groups of "microhymenoptera" (the chalcidoid parasitic wasps) (1246 species) have just been published.The other checklists are to follow over the next several years. The associated data are also being uploaded to the Global Biodiversity Information Facility (GBIF), allowing for periodic updates over time.

When complete, this will be the largest species checklist for any group of organisms in northern North America. Considering that it is estimated that we currently have documented less than half of the species of Hymenoptera present in northern North America, there is still a great amount of work to do on this fascinating group of insects.

Clothing, from tank tops to parkas, helps people adapt to temperatures outdoors. But you can only put on or take off so much of it, and fluctuations in weather can render what you are wearing entirely inadequate. In a new study in ACS' Nano Letters, researchers describe a high-tech alternative: a reversible textile they designed to trap warmth in the cold and reflect it during hot weather, all while generating small amounts of electricity.

Previous attempts to develop such sophisticated textiles for outdoor use have generally focused on either capturing thermal radiation or dispersing it. To integrate the two, Qiang Li, Min Qiu and colleagues made a layered fabric made of porous fibrous polymers. To trap warmth in the cold, they coated the heating side in zinc and copper nanoparticles to absorb solar energy and keep in thermal radiation from the body. To release heat in the hot sun, they placed a hierarchically porous structure on the cooling side to reflect sunlight and dissipate human body radiation. In the sun, the heating side increased a simulated skin's temperature by as much as 14 F more than did black cotton. With the cooling side out, the textile dropped the temperature by 11 F compared to white cotton. In night tests, the heating side warmed the simulated skin by 5 F more than black cotton, but the cooling side did not result in a lower temperature. By attaching a small thermoelectric generator to the textile, the researchers could harness the temperature gradient between its inner surface and skin to produce a small amount of electricity. They say the textile is easy and inexpensive to fabricate and has breathability comparable to cotton. This textile creates new possibilities for many technologies, such as multi-functional camouflage or clothing that can generate electricity to someday power wearable electronics, the researchers say.

The authors acknowledge funding from the National Key R&D Program of China and the National Natural Science Foundation of China.

The abstract that accompanies this paper is available here.

The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS' mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and all its people. The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world's scientific knowledge. ACS' main offices are in Washington, D.C., and Columbus, Ohio.

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In 2005, greenhouse gas (GHG) emissions from residential energy use hit an all-time high in the United States. Each year since, emissions have dropped at an average annual rate of 2 percent.

In a study published in Environmental Research Letters, "Drivers of change in US residential energy consumption and greenhouse gas emissions, 1990-2015," a team of researchers from the Yale School of the Environment (YSE) outlined several factors that have contributed to this decrease, highlighting efficiencies in new home construction, energy consumption and household appliances, as well as less emissions in electric generation.

"Without the reductions in GHG intensity of electricity, residential GHG emissions would have been higher," growing by 30 percent from 1990 to 2015 rather than the current 6 percent, says YSE PhD student Peter Berrill from the Center for Industrial Ecology, who co-authored the paper with Ken Gillingham, associate professor of economics at YSE, and former YSE faculty member Edgar Hertwich.

Using detailed data gathered from multiple U.S. housing surveys and energy reviews, Berrill found positives in less GHG-intensive electricity, but added that it's "too risky" to rely on only electricity to decarbonize the residential sector in the coming decades. This, he says, is due to other troubling trends: population growth; reduction of household size, including more senior citizens living on their own; substantial increases in floor area per house in recent decades; and increased access to residential cooling.

To stem the tide against those trends, Berrill sees a need for societal change.

"Without it, we're not going to see meaningful change," he says. More attention needs to be paid, says Berrill, to building smaller homes, including more multi-family housing, and retrofitting existing homes to be more efficient. He also suggested regional approaches -- for example, population growth is slower in the Northeast and Midwest, and more attention needs to be paid to renovating and retrofitting older homes in areas with slowly growing housing stock.

Berrill, Gillingham and Hertwich also authored a related paper recently published in Environmental Science Technology, focused on how housing policy and types of housing are linked to residential energy demand. The researchers analyzed federal policy changes in the 1970s and 1980s that increased single-family housing construction considerably -- an estimated 14 million new homes by 2015, leading to a greater need for heating and cooling, water and electricity.

The researchers estimate that a shift from single-family housing to multi-family housing could reduce energy demand by as much as 47 percent per household and more than 8 percent across the entire U.S. housing stock.

"Removing policy barriers and disincentives to multifamily housing can unlock a large potential for reducing residential energy demand and GHG emissions in the coming decades," the researchers say.

Leather is an ever growing multi-billion dollar industry requiring more than 3.8 billion bovine animals - equal to one for every two people on earth - to sustain production each year. And while the products - clothing, shoes, furniture and more - can be quite elegant and durable, the environmental impact of leather production has been severe, leading to deforestation, water and land overuse, environmental pollution, and greenhouse gas emissions.

Researchers at Tufts University School of Engineering set out to find an alternative to leather, with similar texture, flexibility and stiffness, yet focused on materials that are sustainable, non-toxic, and friendly to the environment. It turns out, we have been wearing that material all along - it's silk, but instead of weaving the silk into fabric, the Tufts engineers were able to break down the fibers from silkworm cocoons into their protein components, and re-purpose the proteins to form the leather-like material. The process for making silk-based leather is described in a study published in the journal Materials & Design.

The silk-based leather can be printed into different patterns and textures, has similar physical properties to real leather, and can withstand the folding, piercing, and stretching typically used to create leather goods, including the ability to stitch together pieces of material and attach hardware such as rivets, grommets, handles and clasps.

"Our work is centered on the use of naturally-derived materials that minimize the use of toxic chemicals while maintaining material performance so as to provide alternatives for products that are commonly and widely used today," said Fiorenzo Omenetto, Frank C. Doble Professor of Engineering at Tufts School of Engineering, director of the Tufts Silklab where the material was created, and corresponding author of the study. "By using silk, as well as cellulose from textile and agricultural waste and chitosan from shell-fish waste, and all the relatively gentle chemistries used to combine them, we are making progress towards this goal."

There is of course already an existing portfolio of alternative leathers developed by industry and the research community, with a focus on using agricultural byproducts or regenerated materials that have a reduced impact on the environment and animal raising. These include leather-like materials made from petroleum (polyurethane leather or "pleather"), tree bark, pineapple husks, plant oils, rubber, fungi, and even from cellulose and collagen produced by bacterial cultures.

The silk-based leather made at Tufts offers some unique advantages to all of these approaches. In addition to being derived from dissolving silk fibers, manufacturing is water based, using only mild chemicals, conducted at room temperature, and producing mostly non-toxic waste. The silk leather material can be fabricated using computerized 3D layering with the ability to create regular micropatterns that can tune the material's strength and flexibility, print macropatterns for aesthetics (e.g. a basket weave) as well as non-regular geometrical patterning to mimic the surface texture of real leather. The resulting materials, like leather, are strong, soft, pliable, and durable, and like natural leather, they are biodegradable once they enter the waste stream.

In fact, the silk-leather products could be re-dissolved and regenerated into its gel-like stock matter to be re-printed into new products

The process of making the silk leather starts with silk fibers that are commonly used in the textile industry. These fibers are made up of silk fibroin protein polymers, and they can be broken down to its individual protein components in a water-based slurry. A base layer of chitosan containing a non-toxic plasticizer glycerol and dye is printed by extrusion through a tiny bore nozzle onto a surface to provide flexibility and strength to the material. Chitosan is itself derived from natural sources such as the shells of crabs lobsters and shrimp. A layer of silk fibroin combined with plasticizer and a thickener (from vegetable gum) is printed on top of the base layer.

Extruding the fibroin slurry through the printer nozzle creates shear forces that may contribute to arranging the proteins in a way that that strengthens the material, making it ductile rather than brittle, and mimics the natural extrusion that occurs in the silk gland of a worm or spider. Changing the printed pattern of the silk layer can provide a range of appearance, tunable strengths and other physical qualities.

The printing method, also referred to as "additive manufacturing" is known to be very conservative in the use of materials and waste produced compared to other methods like injection molding or subtractive manufacturing (like carving or shaving from a block).

The Silklab at Tufts has developed a wide range of other products from silk, from implantable medical devices to architectural materials that can sense and respond to the environment by changing color. In fact, much of the technology that has been developed in the lab to derivatize the silk proteins can be applied to the silk-based leather, including attaching and embedding molecules that can sense and respond to the surrounding environment.

"That's the advantage of using silk protein over other methods - it has a well-established, versatile chemistry which we can use to tune the qualities of the material and embed smart elements like sensing molecules," said Laia Mogas-Soldevila, former research fellow in the Silklab, currently assistant professor of Architecture at University of Pennsylvania Stuart Weitzman School of Design and first author of the study. "So while there may be many options for leather-like materials, silk-based leather has the potential to be most amenable to innovative designs."

The ant came in a small vial of ethanol, sealed in a plastic bag, and packed in a small cardboard box. It was addressed to Yale's Douglas B. Booher.

German entomologist Phillip Hoenle had discovered the ant, which he noted had some peculiar features, in a rain forest in Ecuador. Now he wanted Booher, a research associate in the Yale Center for Biodiversity and Global Change and the Department of Ecology & Evolutionary Biology, to confirm whether this trap ant was truly a new species. If so, Hoenle and Booher would have the honor of naming it.

Booher had imagined this moment for years. He had even discussed it with an old friend from Athens, Georgia, the artist and former R.E.M. singer Michael Stipe. After receiving the specimen he reached out to Stipe.

"I'm going to name it after Jeremy," Booher said.

Naming a species after Jeremy Ayers was an odd choice. But then Ayers was as unusual as the smooth and shining cuticles and large trap jaw mandibles of the ant that would come to bear his name.

By the early 1970s, Charles "Jeremy" Ayers, the son of a civil rights advocate and religion professor at the University of Georgia, had found the 15 minutes of fame promised by artist and film director Andy Warhol. Working with Warhol, the potentate of New York's pop art scene, Ayers morphed into Silva Thin, one of Warhol's legion of "Superstars" who through elaborate makeup, unusual dress, and exaggerated poses, blurred gender boundaries in the city's avant-garde scene.

The Warhol Foundation still owns portraits of the ultra-slender Thin, with exaggerated eyebrows painted black, ruby red lipstick, dark mascara over the eyes, dressed in silk shirt and tie, languorously waving a cigarette.

In the late 1970s, Ayers returned to his hometown of Athens and helped give birth to a thriving artistic community that spawned some of the most popular American bands of the 1980s, including the B-52's and Stipe's R.E.M. Nestled in the deep South, the college town nurtured a post-Bohemian art scene that drew poets, sculptors, and musicians. The community also welcomed straight, gay, lesbian, and transgender people long before LGBTQ entered the popular lexicon.

And Ayers, philosopher, multi-media artist, and political activist, was the creative straw that stirred this rich stew of creative talent, one person at a time, Stipe recalls.

Stipe and Ayers became close friends; Ayers even wrote songs for R.E.M. So taken with Ayers was Stipe that he asked Ayers to dance to a musical piece he created. In the video, Jeremy's Dance, Ayers moves with awkward purpose and a total lack of self-consciousness to Stipe's synthesized beat. The video was shown at Moogfest, in 2016, soon after Ayers unexpected death following a seizure. He was 68.

"His curiosity for every single person he ever met was the foundation of a fascinating and cross-cultural network of friends, acquaintances, and colleagues, often with Jeremy at the very center of several overlapping colonies," Stipe recalled. "He created the salon, laid the trails; he was the connector, the queen ant if you will, the bringer-togetherer."

Studying -- and celebrating -- the diversity of life

The allure of Athens' creative scene also captured Douglas Booher.

He arrived in 1993 and earned a bachelor's degree at the University of Georgia, where he studied ecology. He always had a love of nature's biodiversity, but eventually dropped his pursuit of a Ph.D. (he was studying the sexual selection and mating practices of the eastern bluebird) to become a building contractor.

For the next 12 years he built his own flooring company, which manufactured and designed custom carpets and installed wood products from demolished buildings. On weekends, however, Booher transformed into DJ cut-a-rug, a disc jockey and performance dancer who, along with his artistic partner, The Big Nastee, led explosive dances late into the Georgia night. One of their performances was memorialized in this video, shot in Jeremy Ayers' garden.

But his love of the natural world never waned. One evening he joined Stipe on a visit with Ayers, who was excited to share a book with Booher. "He knew I loved insects and he had recently bought a book on the Chinese culture of keeping crickets for their sounds," Booher recalled. "He was also endlessly fascinated with nature. He knew it would bring me joy."

The act defined Ayers, who always saw the individual amidst the great diversity of his community.

"He gave people the freedom to be who they wanted to be," Booher said.

By 2012, Booher decided he wanted to pursue a career in entomology, the study of insects. He completed his Ph.D. in ecology and evolutionary biology at UCLA, where his dissertation was on the structure and assembly of ant communities.

Last year, he joined the Yale Center for Biodiversity and Global Change as a postdoctoral associate in the lab of biologist Walter Jetz. Like Ayers' embrace of members of the Athens' art scene, the goal of the Jetz lab was to explore the global diversity of life, one species at a time, he said.

In the case of the new ant found in the forests of Ecuador, its large trap jaw mandibles and shining and smooth cuticles set it apart from more than 850 species of its genus, Strumigenys, Booher determined. This was a new species. And tradition allows the discoverers to name newly discovered life.

Booher and Stipe already knew what they wanted to do. Booher discussed the issue with Hoenle, who agreed that Ayers was a worthy designee. They considered the name Strumigenys ayers.

But knowing that Ayers would shy away from an honor that was solely personal, they wanted to find a name that would also honor the many people across the gender diversity spectrum who he so often championed.

"Naming species in honor of people is a centuries old tradition among taxonomists," Hoenle said. "To honor someone means to respect their self-identity, and gender is part of that."

As it happened, in 2007 a publication clarified that the International Code of Nomenclature did not require that new species carry Latin suffixes based on the gender of the individual being honored. So rather than using one of the traditional Latin suffixes -- either ae, which designates a female, or i for a male, or orum for a group of male and female individuals -- Booher and Stipe adopted a new suffix that recognizes non-binary individuals and honors the spirit of Ayers, an activist who had always fought for, celebrated, and honored the diversity of life, including those gender diverse individuals who didn't fit neatly into a binary category.

They named the ant Strumigenys ayersthey.

"I knew Jeremy, and knew of no other human that better represented the pan and inclusive world of humans," Booher said. "He was also a lover of biodiversity, so it just seemed to fit."

Researchers at CRANN (The Centre for Research on Adaptive Nanostructures and Nanodevices), and the School of Physics at Trinity College Dublin, today announced that a magnetic material developed at the Centre demonstrates the fastest magnetic switching ever recorded.

The team used femtosecond laser systems in the Photonics Research Laboratory at CRANN to switch and then re-switch the magnetic orientation of their material in trillionths of a second, six times faster than the previous record, and a hundred times faster than the clock speed of a personal computer.

This discovery demonstrates the potential of the material for a new generation of energy efficient ultra-fast computers and data storage systems.

The researchers achieved their unprecedented switching speeds in an alloy called MRG, first synthesised by the group in 2014 from manganese, ruthenium and gallium. In the experiment, the team hit thin films of MRG with bursts of red laser light, delivering megawatts of power in less than a billionth of a second.

The heat transfer switches the magnetic orientation of MRG. It takes an unimaginably fast tenth of a picosecond to achieve this first change (1 ps = one trillionth of a second). But, more importantly, the team discovered they could switch the orientation back again 10 trillionths of a second later. This is the fastest re-switching of a magnet's orientation ever observed.

Their results are published this week in the leading physics journal, Physical Review Letters.

The discovery could open new avenues for innovative computing and information technology, given the importance of magnetic materials in this industry. Hidden in many of our electronic devices, as well as in the large-scale data centres at the heart of the internet, magnetic materials read and store the data. The current information explosion generates more data and consumes more energy than ever before. Finding new energy efficient ways to manipulate data, and materials to match, is a world-wide research preoccupation.

The key to the Trinity teams' success was their ability to achieve the ultrafast switching without any magnetic field. Traditional switching of a magnet uses another magnet, which comes at cost in terms of both energy and time. With MRG the switching was achieved with a heat pulse, making use of the material's unique interaction with light.

Trinity researchers Jean Besbas and Karsten Rode discuss one avenue of the research:

"Magnetic materials inherently have memory that can be used for logic. So far, switching from one magnetic state 'logical 0', to another 'logical 1', has been too energy hungry and too slow. Our research addresses speed by showing that we can switch MRG from one state to another in 0.1 picoseconds and crucially that a second switch can follow only 10 picoseconds later, corresponding to an operational frequency of ~ 100 gigahertz -- faster than anything observed before.

"The discovery highlights the special ability of our MRG to effectively couple light and spin so, that we can control magnetism with light and light with magnetism on hitherto unachievable timescales."

Commenting on his team's work, Professor Michael Coey, Trinity's School of Physics and CRANN, said:

"In 2014 when my team and I first announced that we had created a completely new alloy of manganese, ruthenium and gallium, known as MRG, we never suspected the material had this remarkable magneto-optical potential.

"This demonstration will lead to new device concepts based on light and magnetism that could benefit from greatly increased speed and energy efficiency, perhaps ultimately realising a single universal device with combined memory and logic functionality. It is a huge challenge, but we have shown a material that may make it possible. We hope to secure funding and industry collaboration to pursue our work."

Granular materials, such as sand and gravel, are an interesting class of materials. They can display solid, liquid, and gas-like properties, depending on the scenario. But things can get complicated in cases of high-speed vehicle locomotion, which cause these materials to enter a "triple-phase" nature, acting like all three fundamental phases of matter at the same time.

As reported in the April 23, 2021 issue of the journal Science Advances, a team of engineers and physicists from the Massachusetts Institute of Technology (MIT) and Georgia Institute of Technology (GIT) have proposed a new model, Dynamic Resistive Force Theory, or DRFT, to enable near real-time modeling of high-speed motion for arbitrarily shaped objects moving through granular media.

"Applications for this work include the predictive modeling of ground impacts, off-road vehicles, animal locomotion, and extraterrestrial rovers," notes Ken Kamrin, associate professor in the Department of Mechanical Engineering at MIT and the study's corresponding author.

Often, granular materials are modeled grain-by-grain, but this type of approach can be an expensive and slow affair. For instance, modeling one liter of beach sand for just a few seconds might take weeks to process on your average laptop computer.

Researchers have long sought faster ways to accurately model such materials -- and often their overall interest is focused on understanding one piece in the overall modeling puzzle: the net force that a granular material like sand exerts on larger moving bodies.

"This is why, over the past century, scientists and engineers have developed the discipline of 'terramechanics,' which helps predict the locomotive performance of vehicles -- mostly circular wheel and tanks treads -- in granular terrains, like deserts," Kamrin explains. "The majority of the methods used in this discipline remain empirical in nature with little room for customization. DRFT fills this gap and allows for modeling the motion of arbitrary objects moving at various speeds in sands."

DRFT is a joint effort between Kamrin and graduate student Shashank Agarwal (also of Mechanical Engineering at MIT) in collaboration with Daniel Goldman, Dunn Family Professor of Physics and graduate student Andras Karsai (both of School of Physics at GIT).

The research team unearthed the concept of DRFT after careful study of a continuum model of granular media, which -- unlike the grain-by-grain approach -- models the smooth flow of grains.

Their continuum analysis revealed an extended formula for the resistive forces that act on rapidly moving objects. While the static force response of granular media is already known as static RFT (Resistive Force Theory), DRFT's extended formulation includes two "key velocity-dependent effects" when calculating the force on each small piece of an object's surface. One contribution is due to the inertial effect of accelerating the granular media, and the other is, as Goldman explains, a "subtle structural modification," due to the changes in material strength that arise as the granular free-surface profile changes.

"Interestingly, when put together, DRFT captures diverse counterintuitive observations observed in granular locomotion, including the behaviors seen in circular and 'grousered' wheel locomotion, 'c-leg' robot locomotion, and possibly even the locomotion of desert animals like zebra-tailed lizards at high speeds," Goldman notes. "At the same time, DRFT illuminates the dominating physical phenomena occurring in rapid propulsion in grain beds."

"The research is of crucial importance for applications like path planning and optimal locomotor design for terrestrial, as well as extraterrestrial, applications, such as Mars and lunar rovers," adds Kamrin. "While this study specifically focuses on granular materials, it provides a blueprint for developing similar rapid, reduced-order models for other classes of materials like muds and slurries."

The field of photonics aims to transform all manner of electronic devices by storing and transmitting information in the form of light, rather than electricity. Beyond light's raw speed, the way that information can be layered in its various physical properties makes devices like photonic computers and communication systems tantalizing prospects.

Before such devices can go from theory to reality, however, engineers must find ways of making their light sources -- lasers -- smaller, stronger and more stable. Robots and autonomous vehicles that use LiDAR for optical sensing and ranging, manufacturing and material processing techniques that use lasers, and many other applications are also continually pushing the field of photonics for higher power and more efficient laser sources.

Now, a team of researchers from the University of Pennsylvania's School of Engineering and Applied Science have drawn from concepts at the edge of theoretical physics to design and build two-dimensional arrays of closely packed microlasers that have the stability of a single microlaser but can collectively achieve power density orders of magnitude higher.

They have now published a study demonstrating their supersymmetric microlaser array in the journal Science.

The study was led by Liang Feng, associate professor in the Departments of Materials Science and Engineering and Electrical and Systems Engineering, along with Xingdu Qiao, Bikashkali Midya and Zihe Gao, members of his lab. They collaborated with fellow Feng lab members Zhifeng Zhang, Haoqi Zhao, Tianwei Wu and Jieun Yim as well as Ritesh Agarwal, professor in the Department of Materials Science and Engineering. Natalia M. Litchinitser, professor of Electrical and Computer Engineering at Duke University, also contributed to the research.

In order to preserve the information manipulated by a photonic device, its lasers must be exceptionally stable and coherent. So-called "single-mode" lasers eliminate noisy variations within their beams and improve their coherence, but as a result, are dimmer and less powerful than lasers that contain multiple simultaneous modes.

"One seemingly straightforward method to achieve a high-power, single-mode laser," Feng says, "is to couple multiple identical single-mode lasers together to form a laser array. Intuitively, this laser array would have an enhanced emission power, but because of the nature of complexity associated with a coupled system, it will also have multiple 'supermodes.' Unfortunately, the competition between modes makes the laser array less coherent."

Coupling two lasers produces two supermodes, but that number increases quadratically as lasers are arrayed in the two-dimensional grids eyed for photonic sensing and LiDAR applications.

"Single mode operation is critical," Qiao says, "because the radiance and brightness of the laser array increase with number of lasers only if they are all phase-locked into a single supermode."

"Inspired by the concept of supersymmetry from physics," he says, "we can achieve this kind of phase-locked single-mode lasing in a laser array by adding a dissipative 'superpartner.'"

In particle physics, supersymmetry is the theory that all elementary particles of the two main classes, bosons and fermions, have a yet undiscovered "superpartner" in the other class. The mathematical tools that predict the properties of each particle's hypothetical superpartner can also be applied to the properties of lasers.

Compared to elementary particles, fabricating a single microlaser's superpartner is relatively simple. The complexity lies in adapting supersymmetry's mathematical transformations to produce an entire superpartner array that has the correct energy levels to cancel out all but the desired single mode of the original.

Prior to Feng and his colleagues' work, superpartner laser arrays could only have been one-dimensional, with each of the laser elements aligned in a row. By solving the mathematical relationships that govern the directions in which the individual elements couple to one another, their new study demonstrates an array with five rows and five columns of microlasers.

"When the lossy supersymmetric partner array and the original laser array are coupled together," Gao says, "all of the supermodes except for the fundamental mode are dissipated, resulting in single-mode lasing with 25 times the power and more than 100 times the power density of the original array. We envision a much more dramatic power scaling by applying our generic scheme for a much larger array even in three dimensions. The engineering behind is the same."

The researchers' study also shows that their technique is compatible with their earlier research on vortex lasers, which can precisely control orbital angular momentum, or how a laser beam spirals around its axis of travel. The ability to manipulate this property of light could enable photonic systems encoded at even higher densities than previously imagined.

"Single-mode, high-power lasing is used in a wide range of important applications, including optical communications, optical sensing and LIDAR ranging," says James Joseph, program manager, Army Research Office, an element of the U.S. Army Combat Capabilities Development Command's Army Research Laboratory, which supported this study. "The research results out of Penn mark a significant step towards creating more efficient and fieldable laser sources."

Scientists are certain that dark matter exists. Yet, after more than 50 years of searching, they still have no direct evidence for the mysterious substance.

University of Delaware's Swati Singh is among a small group of researchers across the dark matter community that have begun to wonder if they are looking for the right type of dark matter.

"What if dark matter is much lighter than what traditional particle physics experiments are looking for?" said Singh, an assistant professor of electrical and computer engineering at UD.

Now, Singh, Jack Manley, a UD doctoral student, and collaborators at the University of Arizona and Haverford College, have proposed a new way to look for the particles that might make up dark matter by repurposing existing tabletop sensor technology. The team recently reported their approach in a paper published in Physical Review Letters.

Co-authors on the paper include Dalziel Wilson, an assistant professor of optical sciences from Arizona, Mitul Dey Chowdhury, an Arizona doctoral student, and Daniel Grin, an assistant professor of physics at Haverford College.

No ordinary matter

Singh explained that if you add up all the things that emit light, such as stars, planets and interstellar gas, it only accounts for about 15% of the matter in the Universe. The other 85% is known as dark matter. It doesn't emit light, but researchers know it exists by its gravitational effects. They also know it isn't ordinary matter, such as gas, dust, stars, planets and us.

"It could be made up of black holes, or it could be made up of something trillions of times smaller than an electron, known as ultralight dark matter" said Singh, a quantum theorist known for her pioneering efforts to push forward mechanical dark matter detection.

One possibility is that dark matter is made up of dark photons, a type of dark matter that would exert a weak oscillating force on normal matter, causing a particle to move back and forth. However, since dark matter is everywhere, it exerts that force on everything, making it hard to measure this movement.

Singh and her collaborators said they think they can overcome this obstacle by using optomechanical accelerometers as sensors to detect and amplify this oscillation.

"If the force is material dependent, by using two objects composed of different materials the amount that they are forced will be different, meaning that you would be able to measure that difference in acceleration between the two materials," said Manley, the paper's lead author.

Wilson, a quantum experimentalist and one of the UD team's collaborators, likened an optomechanical accelerometer to a miniature tuning fork. "It's a vibrating device which, due to its small size, is very sensitive to perturbations from the environment," he said.

Now, the researchers have proposed an experiment using a membrane made of silicon nitride and a fixed beryllium mirror to bounce light between the two surfaces. If the distance between the two materials changes, the researchers would know from the reflected light that dark photons were present because the silicon nitride and beryllium have different material properties.

Collaboration was a key part of developing the experiment's design, according to Manley. He and Singh (theorists) worked with Wilson and Dey Chowdhury (experimentalists) on the theoretical calculations that went into the detailed blueprint for building their proposed tabletop accelerometer sensor. Meanwhile, Grin, a cosmologist, helped shed light on the particle physics aspects of ultralight dark matter, such as why it would be ultralight, why it might couple to materials differently and how it might be produced.

As a theorist, Manley said the opportunity to learn more about how devices work and how experimentalists build things to prove the theories that he and Singh develop has deepened his expertise while simultaneously widening his exposure to possible career paths.

A growing body of work

Importantly, this latest work builds on previously published research by the collaborating teams, reported last summer in Physical Review Letters. The paper, which included contributions from former UD graduate student Russell Stump, showed that several existing and near-term laboratory-scale devices are sensitive enough to detect, or rule out, possible particles that could be ultralight dark matter.

The research reported that certain types of ultralight dark matter would connect, or couple, with normal matter in a way that would cause a periodic change in the size of atoms. While small fluctuations in the size of a single atom may be difficult to notice, the effect is amplified in an object composed of many atoms, and further amplification can be achieved if that object is an acoustic resonator. The collaboration evaluated the performance of several resonators made of diverse materials ranging from superfluid helium to single-crystalline sapphire, and found these sensors can be used to detect that dark matter-induced strain signal.

Both projects were supported in part through Singh's funding from the National Science Foundation to explore emerging ideas around using state-of-the-art quantum devices to detect astrophysical phenomena with tabletop technologies that are smaller and less expensive than other methods.

Together, Singh said, these papers extend the body of work on what is known about possible ways to detect dark matter and suggest the possibility of a new generation of table-top experiments.

Singh and Manley are working with other experimental groups, too, to develop additional tabletop sensors to look for such dark matter or other weak astrophysical signals. They also are actively cultivating broader discussions on this topic within the dark matter and quantum sensors communities.

For example, Singh recently discussed transformational instrumentation advances in particle physics detectors at a virtual workshop organized by the Department of Energy's Coordinating Panel for Advanced Detectors (CPAD). She also presented these results at a special workshop during the American Physical Society's April meeting.

"It's an exciting time, and I am learning a lot from the questions posed by scientists from diverse backgrounds at such workshops," said Singh. "But it's worth noting that my most original research ideas still come out of questions posed by curious students."

ARLINGTON, TX (May 5, 2021) -- Nanoscope Technologies LLC, a biotechnology company developing gene therapies for treatment of retinal diseases, is featuring multiple scientific presentations highlighting its groundbreaking research on optical gene delivery for vision restoration and OCT-guided electrophysiology platforms for characterization of retinal degeneration and assessment of efficacy of cell-gene therapy at the 2021 ARVO annual (virtual) meeting, May 1-7.

ARVO, the Association for Research in Vision and Ophthalmology, is the largest eye and vision research organization in the world with nearly 11,000 members in more than 75 countries.

Nanoscope's lead product is an optogenetic gene therapy, vMCO-010, that delivers light- sensitive Multi-Characteristics Opsin (MCO) into retinal cells to restore vision in patients with retinal degeneration. If successful, the optogenetic therapy would be the first treatment aimed at correcting these retinal diseases.

Nanoscope also is developing an alternative, non-viral light-based gene delivery method that is designed to be more targeted with less immunogenicity. The upcoming presentations below on Thursday, May 6, highlight Nanoscope's Optical Coherence Tomography (OCT)-guided optical gene delivery platform technology enabling robust expression of MCO in degenerated retina and OCT-guided electrophysiology platform for monitoring efficacy of cell-gene therapy.

Optical coherence tomography guided laser gene delivery in degenerated retina
Author(s): Biraj Mahato, Sanghoon Kim, Houssam Al-Saad, Subrata Batabyal, Michael Carlson, Samarendra Mohanty
10:15 AM - 12:00 PM CDT on Thursday, May 6

Valeria Canto Soler, Ph.D., Director of CellSight Ocular Stem Cell and Regeneration Program at University of Colorado Denver School of Medicine, will highlight Nanoscope's Hot Topic presentation OCT guided micro-focal ERG system with multiple stimulation wavelengths for characterization of ocular health as part of her talk.

3:30 PM to 3:42 PM CDT on Thursday, May 6

In addition on Saturday, May 1, Nanoscope Founder, President and Chief Scientific Officer Samarendra Mohanty, Ph.D., led a presentation titled: An OCT guided laser microirradiation system for development of animal model of retinal degeneration Author(s): Sanghoon Kim, Michael Carlson, Subrata Batabyal, Weldon Wright, Samarendra Mohanty

Investigators found similarities in the bacterial composition of the mouth among patients with early rheumatoid arthritis and those at risk of developing the disease, compared with healthy individuals who were not at risk. The findings come from a study published in Arthritis & Rheumatology.

Patients and at-risk individuals had an increased relative abundance of potentially pro- inflammatory bacteria in the mouth, suggesting a possible link between oral microbes and rheumatoid arthritis.

"Prevotella and Veillonella--both gram-negative anaerobes--were at higher relative abundance in saliva, and Veillonella was also at higher relative abundance in tongue coating, of both early rheumatoid arthritis patients and at-risk individuals compared to healthy controls," the authors wrote.

To improve our own health and the health of our planet, dietary habits will need to change. Because the composition of an optimal diet changes depending on the combination of location, season, and personalized dietary needs, investigators have built a tool that uses an extensive database of food items, nutrients, and environmental-impacts to develop optimized diets specific to an individual in a given country and month. As described in an article published in the Journal of Industrial Ecology, the tool breaks new ground: it can be used to develop personalized, healthful, low-impact diets for people around the world.

The researchers used their method to compare what low-impact diets would look like depending on country (Switzerland vs. Spain), season (August vs. February), sex, the inclusion of dietary supplements, and for different diet types and environmental impacts.

"Managing to consume a diet that meets your specific nutrient needs and reduces disease risk, while also considering the many layers of environmental impacts associated with your food choices can be overwhelming," said lead author Christie Walker, PhD, of the Institute of Environmental Engineering ETH Zurich, in Switzerland. "This tool was developed to guide individuals in building their own personal diets that are both healthy and low impact for climate change and biodiversity, while taking into account the many stages of a food's life cycle."

Researchers have discovered the most precise way to control individual ions using holographic optical engineering technology.

The new technology uses the first known holographic optical engineering device to control trapped ion qubits. This technology promises to help create more precise controls of qubits that will aid the development of quantum industry-specific hardware to further new quantum simulation experiments and potentially quantum error correction processes for trapped ion qubits.

"Our algorithm calculates the hologram's profile and removes any aberrations from the light, which lets us develop a highly precise technique for programming ions," says lead author Chung-You Shih, a PhD student at the University of Waterloo's Institute for Quantum Computing (IQC).

Kazi Rajibul Islam, a faculty member at IQC and in physics and astronomy at Waterloo is the lead investigator on this work. His team has been trapping ions used in quantum simulation in the Laboratory for Quantum Information since 2019 but needed a precise way to control them.

A laser aimed at an ion can "talk" to it and change the quantum state of the ion, forming the building blocks of quantum information processing. However, laser beams have aberrations and distortions that can result in a messy, wide focus spot, which is a problem because the distance between trapped ions is a few micrometers - much narrower than a human hair.

The laser beam profiles the team wanted to stimulate the ions would need to be precisely engineered. To achieve this they took a laser, blew its light up to 1cm wide and then sent it through a digital micromirror device (DMD), which is programable and functions as a movie projector. The DMD chip has two-million micron-scale mirrors on it that are individually controlled using electric voltage. Using an algorithm that Shih developed, the DMD chip is programmed to display a hologram pattern. The light produced from the DMD hologram can have its intensity and phase exactly controlled.

In testing, the team has been able to manipulate each ion with the holographic light. Previous research has struggled with cross talk, which means that if a laser focuses on one ion, the light leaks on the surrounding ions. With this device, the team successfully characterizes the aberrations using an ion as a sensor. They can then cancel the aberrations by adjusting the hologram and obtain the lowest cross talk in the world.

"There is a challenge in using commercially available DMD technology," Shih says. "Its controller is made for projectors and UV lithography, not quantum experiments. Our next step is to develop our own hardware for quantum computation experiments."

New Edith Cowan University (ECU) research has found that by eating just one cup of nitrate-rich vegetables each day people can significantly reduce their risk of heart disease.

The study investigated whether people who regularly ate higher quantities of nitrate-rich vegetables, such as leafy greens and beetroot, had lower blood pressure, and it also examined whether these same people were less likely to be diagnosed with heart disease many years later.

Cardiovascular diseases are the number one cause of death globally, taking around 17.9 million lives each year.

Researchers examined data from over 50,000 people residing in Denmark taking part in the Danish Diet, Cancer, and Health Study over a 23-year period. They found that people who consumed the most nitrate-rich vegetables had about a 2.5 mmHg lower systolic blood pressure and between 12 to 26 percent lower risk of heart disease.

Lead researcher Dr Catherine Bondonno from ECU's Institute for Nutrition Research said identifying diets to prevent heart disease was a priority.

"Our results have shown that by simply eating one cup of raw (or half a cup of cooked) nitrate-rich vegetables each day, people may be able to significantly reduce their risk of cardiovascular disease," Dr Bondonno said.

"The greatest reduction in risk was for peripheral artery disease (26 percent), a type of heart disease characterised by the narrowing of blood vessels of the legs, however we also found people had a lower risk of heart attacks, strokes and heart failure."

Forget the supplements

The study found that the optimum amount of nitrate-rich vegetables was one cup a day and eating more than that didn't seem to give any additional benefits.

"People don't need to be taking supplements to boost their nitrate levels because the study showed that one cup of leafy green vegetables each day is enough to reap the benefits for heart disease," Dr Bondonno said.

"We did not see further benefits in people who ate higher levels of nitrate rich vegetables."

Smoothies are ok

Dr Bondonno said hacks such as including a cup of spinach in a banana or berry smoothie might be an easy way to top up our daily leafy greens.

"Blending leafy greens is fine, but don't juice them. Juicing vegetables removes the pulp and fibre," Dr Bondonno said.

The paper "Vegetable nitrate intake, blood pressure and incident cardiovascular disease: Danish Diet, Cancer, and Health Study" is published in the European Journal of Epidemiology. It is a collaboration between Edith Cowan University, the Danish Cancer Society and The University of Western Australia.

The research adds to growing evidence linking vegetables generally and leafy greens specifically with improved cardiovascular health and muscle strength. This evidence includes two recent ECU studies exploring cruciferous vegetables and blood vessel health and green leafy vegetables and muscle strength.

Over the coming decades, our economy and society will need to dramatically reduce greenhouse gas emissions as called for in the Paris Agreement. But even a future low-carbon economy will emit some greenhouse gases, such as in the manufacture of cement, steel, in livestock and crop farming, and in the chemical and pharmaceutical industries. To meet climate targets, these emissions need to be offset. Doing so requires "negative emissions" technologies, by means of which CO2 is removed from the atmosphere and permanently stored in underground repositories.

Researchers at ETH Zurich have now calculated the potential of one of these technologies for Europe: the combination of energy extraction from biomass with the capture and storage of CO2, or bioenergy with carbon capture and storage (BECCS) as it is known. The calculations revealed that if BECCS were exploited to its full potential, it would reduce carbon emissions in Europe by 200 million tonnes per year. This represents 5 percent of European emissions in 2018 and a substantial proportion of the 7.5 billion tonnes of CO2 that Europe has to cumulatively save by 2050 to reach its climate targets. As the authors of the study also point out, however, fully exploiting the calculated potential of BECCS will be challenging in practice.

Technology ready for action

BECCS involves capturing CO2 at the point sources where it is produced from biological material. In Europe, companies in the pulp and paper industry offer the greatest potential. Other sectors with potential are waste incineration plants (where around half the waste is from biomass), combined heat and power plants that run on wood, and biogas plants that use compostable municipal waste or plant and animal byproducts of food production that are not suitable for eating. Further sources are wastewater treatment plants and livestock manure.

"The technology for capturing carbon dioxide at such point sources is ready to go," explains Marco Mazzotti, Professor at the Institute of Energy and Process Engineering and head of the study. The carbon would then have to be transported to storage locations via a network yet to be created - in pipelines, for instance. "This is a major challenge," says Lorenzo Rosa, scientist in Mazzotti's group and lead author of the study. After all, CO2 is produced unevenly across Europe. Suitable storage sites are now present only in a few places, far from the CO2 point sources, such as underneath the seabed of the North Sea. However, this challenge is solvable if such a transport network were to be built up as quickly as possible, says Rosa.

Paper industry

As the calculations of the ETH researchers revealed, the potential of BECCS varies greatly from country to country. At one extreme is Sweden, which has a strong pulp and paper industry. By using BECCS, Sweden could capture almost three times as much carbon dioxide from biomass (and thus atmospheric origin) as it emits from fossil fuels today. "If Sweden were to exploit its full BECCS potential, it could trade emission certificates and thus offset emissions in other countries," says Rosa. Finland and Estonia could reduce their CO2 emissions by half, also possible thanks to a strong pulp and paper industry. In many other European countries, the potential is lower, with emissions reductions of around 5 percent or less.

For their calculations, the ETH scientists took into account only biomass that arises as a byproduct of industry or agriculture or as waste. They deliberately factored out crops grown for the primary purpose of energy production, a practice that is more widespread in other regions of the world than in Europe. Because such farming is in direct competition with food crops, it is not considered very sustainable. "With global food demand expected to double by 2050, there is a pressing need to develop BECCS technologies that do not rely on purpose-grown bio-energy plantations," says Rosa.

Waste as raw material

In Switzerland, the BECCS potential is about 6 percent. Waste incineration plants could make up a large portion of this total. "In many other regions of Europe, by contrast, this potential lies idle, as waste is dumped unused in landfills," says ETH Professor Mazzotti.

Waste incineration plants already fulfil three important functions today: they dispose of waste; they recycle raw materials, as far as possible; and they generate district heating and electricity. "Now a fourth function is being added: as significant negative emissions facilities, waste incineration plants can help reduce the carbon footprint of our society," says Mazzotti. At present, this potential is going untapped. For the most part, no carbon dioxide is being captured yet in paper, incineration or biogas plants. In the opinion of the ETH researchers, we should start doing so as soon as possible.