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Cyber attackers could target 3D printed objects in health care, aerospace, and other fields. Cybersecurity researchers at Rutgers University-New Brunswick and the Georgia Institute of Technology have proposed new ways to protect 3D printed objects such as drones, prostheses, and medical devices from stealthy “logic bombs.” The researchers will present their paper, titled “Physical Logic Bombs in 3D Printers via Emerging 4D Techniques,” at the 2021 Annual Computer Security Applications Conference on December 10, 2021....

New study on early human fire acquisition squelches debate. Fire starting is a skill that many modern humans struggle with in the absence of a lighter or matches. The earliest humans likely harvested fire from natural sources, yet when our ancestors learned the skills to set fire at will, they had newfound protection, a means of cooking, light to work by, and warmth at their fingertips. Just when this momentous acquisition of knowledge occurred has been a hotly debated topic for archaeologists....

Just a year ago, the National Science Foundation-funded Laser Interferometer Gravitational-wave Observatory, or LIGO, was picking up whispers of gravitational waves every month or so. Now, a new addition to the system is enabling the instruments to detect these ripples in space-time nearly every week. Since the start of LIGO’s third operating run in April, a new instrument known as a quantum vacuum squeezer has helped scientists pick out dozens of gravitational wave signals, including one that appears to have been generated by a binary neutron star — the explosive merging of two neutron stars....

Astronomers say that magnetic storms in the gas orbiting young stars may explain a mystery that has persisted since before 2006. Researchers using NASA’s Spitzer Space Telescope to study developing stars have had a hard time figuring out why the stars give off more infrared light than expected. The planet-forming disks that circle the young stars are heated by starlight and glow with infrared light, but Spitzer detected additional infrared light coming from an unknown source....

The ice cap is a permanent fixture, but in the winter season – as it is now in early 2017 – temperatures are cold enough for around 30 percent of the carbon dioxide in the planet’s atmosphere to precipitate onto the cap, adding a seasonal layer up to a meter thick. During the warmer summer months most of the carbon dioxide ice turns directly into gas and escapes into the atmosphere, leaving behind the water-ice layers....

Catalysis may initiate almost all modern industrial manufacturing processes, but catalytic activity on solid surfaces is poorly understood. This is especially true for the cellulase enzymes used to release fermentable sugars from cellulosic biomass for the production of advanced biofuels. Now, researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) through support from the Energy Biosciences Institute (EBI) have literally shed new light on cellulase catalysis. Using an ultrahigh-precision visible light microscopy technique called PALM – for Photo-Activated Localization Microscopy – the researchers have found a way to improve the collective catalytic activity of enzyme cocktails that can boost the yields of sugars for making fuels....

The findings highlight the importance of sleep therapy for those at high risk of the disease and eye exams for those with chronic sleep disorders to check for early signs of glaucoma Glaucoma is a leading cause of blindness and will likely affect an estimated 112 million people worldwide by 2040. Characterized by progressive loss of light-sensitive cells in the eye and optic nerve damage, its causes and contributory factors are still poorly understood....

Billions of years ago when the planets of our solar system were still young, Mars was a very different world. Liquid water flowed in long rivers that emptied into lakes and shallow seas. A thick atmosphere blanketed the planet and kept it warm. In this cozy environment, living microbes might have found a home, starting Mars down the path toward becoming a second life-filled planet next door to our own....

Charged particles are produced by the high temperatures of the gas, and their motions produce powerful, dynamic magnetic fields. Those field lines can sometimes break apart forcefully, but the movement of the underlying charged particles often leads them to reconnect. There are two important, longstanding, and related questions about the hot solar wind: how is it heated, and how does the corona produce the wind? Astronomers suspect that magnetic reconnection in the chromosphere plays a key role....

In theory, quantum computers should be able to perform certain kinds of complex calculations much faster than conventional computers, and quantum-based communication could be invulnerable to eavesdropping. But producing quantum components for real-world devices has proved to be fraught with daunting challenges. Now, a team of researchers at MIT and Harvard University has achieved a crucial long-term goal of such efforts: the ability to convert a laser beam into a stream of single photons, or particles of light, in a controlled way....

The rolling hills northwest of Johannesburg are famous for fossils of human-like creatures called hominins. Because of this, the area is known as the Cradle of Humankind. “During our field school excavations at Drimolen, a student began uncovering a cluster of fragments. We could see that they were parts of a skull. But they weren’t immediately identifiable,” says Ms. Stephanie Baker. Baker is a researcher and Ph.D. candidate at the Palaeo-Research Institute at the University of Johannesburg....

Because these materials are so new, however, it has been difficult for scientists to identify and characterize Weyl semimetals. A recent theory and modeling study from scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory may not only give researchers an easier way of finding Weyl semimetals, but also a way to more easily manipulate them for potential spintronic devices. Previous attempts to investigate Weyl semimetals relied on a complicated technique requiring an X-ray or a laser source and carefully prepared samples....

Newly discovered properties in the compound uranium ditelluride, or UTe2, show that it could prove highly resistant to one of the nemeses of quantum computer development — the difficulty with making such a computer’s memory storage switches, called qubits, function long enough to finish a computation before losing the delicate physical relationship that allows them to operate as a group. This relationship, called quantum coherence, is hard to maintain because of disturbances from the surrounding world....

After his PhD thesis invalidates an old assumption, Norman Cao wonders what’s next. “What are some challenges in controlling plasma and what are your solutions? What is the most effective type of fusion device? What are some difficulties in sustaining fusion conditions? What are some obstacles to receiving fusion funding?” For the past four years, graduate student Norman Cao ’15 PhD ’20 has been the Plasma Science and Fusion Center’s (PSFC’s) go-to “answer man,” replying to questions like these emailed by students and members of the general public interested in getting a deeper understanding of fusion and its potential as a future energy source....

Since spring 2020, researchers at Danderyd Hospital and Karolinska Institutet have conducted the so-called COMMUNITY study, with the main purpose of examining immunity after COVID-19. In the first phase of the study in spring 2020, blood samples were collected from 2,149 employees at Danderyd Hospital, of whom about 19 percent had antibodies against SARS-CoV-2. Blood samples have since then been collected every four months, and study participants have responded to questionnaires regarding long-term symptoms and their impact on the quality of life....

Creativity is one of the cognitive functions that enable us to be flexible in new environments and solve problems in unique scenarios. The exceptional circumstances surrounding the first COVID-19 pandemic containment required us to reconsider our routines, set new limits, and adapt… in short, to be creative. Using a two-part questionnaire, a group of researchers from the Frontlab at the Paris Brain Institute conducted an online survey to analyze the influence of the lockdown on creativity....

The virus that causes COVID-19, called SARS-CoV-2, uses its spike protein in order to stick to and infect our cells. The final step for the virus to enter our cells is for part of its spike protein to act like a twist tie, forcing the host cell’s outer membrane to fuse with the virus. Kailu Yang, in the lab of Axel Brunger, colleagues at Stanford University, and collaborators at the University of California Berkeley, Harvard Medical School, and the University of Finland have generated a molecule based on the twisted part of the spike protein (called HR2), which sticks itself onto the virus and prevents the spike protein from twisting....

We can frequently find in our daily lives a localized wave structure that maintains its shape upon propagation—picture a smoke ring flying in the air. Similar stable structures have been studied in various research fields and can be found in magnets, nuclear systems, and particle physics. In contrast to a ring of smoke, they can be made resilient to perturbations. This is known in mathematics and physics as topological protection....

The rate of this oxygen-generating reaction has been incredibly tricky to pin down. But if researchers can get a good enough estimate of what’s known as the “radiative capture reaction rate,” they can begin to work out the answers to fundamental questions, such as the ratio of carbon to oxygen in the universe. An accurate rate might also help them determine whether an exploding star will settle into the form of a black hole or a neutron star....

The universe has a number of bizarre properties that are difficult to understand with everyday experience. For example, the matter we know, consisting of elementary and composite particles building molecules and materials, apparently makes up only a small part of the energy of the universe. The largest contribution, about two-thirds, comes from “dark energy” – a hypothetical form of energy whose background physicists are still puzzling over. Moreover, the universe is not only expanding steadily, but also doing so at an ever-faster pace....