An international team of researchers working at SLAC National Accelerator Laboratory has demonstrated that a bent silicon crystal can bend the paths of focused, very energetic electron beams much more than magnets used today. The method could be of interest for particle accelerator applications such as next-generation x-ray lasers that will help scientists unravel atomic structures and motions in unprecedented detail.
Delivering the capability to image nanostructures and chemical reactions down to nanometer...
Graphene shows great promise for future electronics, advanced solar cells, protective coatings...
Researchers have long sought alternatives to morphine that curb its side effects, including...
Scientists have used an x-ray laser at SLAC National Accelerator Laboratory to get the first glimpse of the transition state where two atoms begin to form a weak bond on the way to becoming a molecule. This fundamental advance, long thought impossible, will have a profound impact on the understanding of how chemical reactions take place.
Imagine thousands of copies of a single protein organizing into a coat of chainmail armor that protects the wearer from harsh and ever-changing environmental conditions. That is the case for many microorganisms. In a new study, researchers with Lawrence Berkeley National Laboratory have uncovered key details in this natural process that can be used for the self-assembly of nanomaterials into complex 2- and 3-D structures.
Facing a challenge akin to solving a 1,000-piece jigsaw puzzle while blindfolded, and without touching the pieces, many structural biochemists thought it would be impossible to determine the atomic structure of a massive cellular machine called the nuclear pore complex, which is vital for cell survival. But after 10 years of attacking the problem, a team recently solved almost a third of the puzzle.
A more accurate view of the structure of the oxygen-evolving complex that splits water during photosynthesis is now in hand thanks to a study involving researchers from the RIKEN SPring-8 Center, Okayama Univ. and the Japan Science and Technology Agency. The new model of natural photosynthesis provides a blueprint for synthesizing water-splitting catalysts that mimic this natural process.
Proteins are the building blocks of all living things, and they exist in virtually unlimited varieties, most of whose highly complex structures have not yet been determined. Those structures could be key to developing new drugs or to understanding basic biological processes. But figuring out the arrangement of atoms in these complicated, folded molecules usually requires getting them to form crystals large enough to be observed in detail.
Bacteria have a sophisticated means of defending themselves, and they need it: more viruses infect bacteria than any other biological entity. Two experiments undertaken at the SLAC National Accelerator Laboratory provide new insight at the heart of bacterial adaptive defenses in a system called CRISPR, short for Clustered Regularly Interspaced Short Palindromic Repeat.
Valium, one of the best known antianxiety drugs, produces its calming effects by binding with a particular protein in the brain. But the drug has an almost equally strong affinity for a completely different protein. Understanding this secondary interaction might offer clues about Valium's side effects and point the way to more effective drugs.
To understand diseases like Parkinson’s, the tiniest of puzzles may hold big answers. That’s why a team including scientists from NIST have determined how two potentially key pieces of the Parkinson’s puzzle fit together, in an effort to reveal how the still poorly understood illness develops and affects its victims.
Researchers working in part at the SLAC National Accelerator Laboratory have discovered that a key protein for cell health, which has recently been linked to diabetes, cancer and other diseases, can multitask by having two identical protein parts divide labor. The TH enzyme, short for transhydrogenase, is a crucial protein for most forms of life. In humans and other higher organisms, it works within mitochondria.
In a marathon, everyone starts at roughly the same place at roughly the same time. But the faster runners will gradually increase their lead, and in the end, the distribution of runners on the street will be very broad. Something similar happens to a pulse of light sent through a medium. The pulse is a combination of different colors (or wavelengths), and when they are sent through a medium like glass, they travel at different speeds.
Scientists have long known that the speed of light can be slowed slightly as it travels through materials such as water or glass. However, it has generally been thought impossible for particles of light, known as photons, to be slowed as they travel through free space, unimpeded by interactions with any materials.
New laser-driven compression experiments reproduce the conditions deep inside exotic super-Earths and giant planet cores, and the conditions during the violent birth of Earth-like planets, documenting the material properties that determined planet formation and evolution processes. The experimentsreveal the unusual properties of silica under the extreme pressures and temperatures relevant to planetary formation and interior evolution.
Yale Univ. astronomers have identified the first “changing look” quasar, a gleaming object in deep space that appears to have its own dimmer switch. The discovery may offer a glimpse into the life story of the universe’s great beacons. Quasars are massive, luminous objects that draw their energy from black holes. Until now, scientists have been unable to study both the bright and dim phases of a quasar in a single source.
The generation of cosmic magnetic fields has long intrigued astrophysicists. Since it was first described in 1959, a phenomenon known as Weibel filamentation instability has generated tremendous theoretical interest from astrophysicists and plasma physicists as a potential mechanism for seed magnetic field generation in the universe. However, direct observation of Weibel-generated magnetic fields remained challenging for decades.
Scientists from the Univ. of Southampton have developed a new technique to generate more powerful, more energy-efficient and low-cost pulsed lasers. The technique, which was developed by researchers from the university's Optoelectronics Research Centre (ORC), has potential applications in a number of fields that use pulsed lasers including telecommunications, metrology, sensing and material processing.
Many of today's most promising renewable energy technologies rely upon catalysts to expedite the chemical reactions at the heart of their potential. Catalysts are materials that enhance chemical reactions without being consumed in the process. For over a century, engineers across the world have engaged in a near-continual search for ways to improve catalysts for their devices and processes.
Scientists have succeeded in reading parts of an ancient scroll that was buried in a volcanic eruption almost 2,000 years ago, holding out the promise that the world's oldest surviving library may one day reveal all of its secrets. The scroll is among hundreds retrieved from the remains of a lavish villa at Herculaneum that, along with Pompeii, was one of several Roman towns that were destroyed when Mt. Vesuvius erupted in A.D. 79.
By zapping ordinary metals with femtosecond laser pulses researchers from the Univ. of Rochester have created extraordinary new surfaces that efficiently absorb light, repel water and clean themselves. The multifunctional materials could find use in durable, low maintenance solar collectors and sensors.
The time frames, in which electrons travel within atoms, are unfathomably short. For example, electrons excited by light change their quantum-mechanical location within mere attoseconds. But how fast do electrons whiz across distances corresponding to the diameter of individual atomic layers?
Training of first responders on the hazards of actual radiological and nuclear threats has been challenged by the difficulties of adequately representing those threats. Training against such threats would involve using hazardous, highly radioactive materials, experiencing actual radiation doses in training, or require the distribution of radioactive material over a large geographical area.
A simple method to sense DNA, as well as potential biomarker proteins of cancer or other diseases such as Alzheimer's, may soon be within reach thanks to the work of a team of Yokohama National Univ. researchers in Japan. As the team reports in Applied Physics Letters, they created a photonic crystal nanolaser biosensor capable of detecting the adsorption of biomolecules based on the laser's wavelength shift.
For swimming through sand, a slick and slender snake can perform better than a short and stubby lizard. That’s one conclusion from a study of the movement patterns of the shovel-nosed snake, a native of the Mojave Desert of the southwest U.S.
The work, published in Nature Communications, demonstrates that the new material presents efficient and degradation-resistant laser emission in the blue, a spectral region of interest in applications such as spectroscopy or materials processing, among others.
In a promising lithium-based battery, the formation of a highly conductive silver matrix transforms a material otherwise plagued by low conductivity. To optimize these multi-metallic batteries, scientists needed a way to see where, when and how these silver, nanoscale "bridges" emerge. Now, researchers have used x-rays to map this changing atomic architecture and revealed its link to the battery's rate of discharge.
Enzymes are catalysts that speed up chemical reactions in living organisms and control many cellular biological processes by converting a molecule, or substrate, into a product used by the cell. For scientists, understanding details of how enzymes work is essential to the discovery of drugs to cure diseases and treat disorders.
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