When a metal tube lines an oil well thousands of feet below the surface of the ocean, that metal had better be solid and reliable. Unfortunately, the environment in such deep wells is often rich in hydrogen, a gas that can penetrate high-tech alloys and make them brittle, making fractures and leaks more likely. Now researchers have figured which characteristics of a metal structure foster this embrittlement in the presence of hydrogen.
Farmers have long noted a correlation between rainstorms and disease outbreaks among plants. Fungal parasites known as “rust” can grow particularly rampant following rain events, eating away at the leaves of wheat and potentially depleting crop harvests. While historical weather records suggest rainfall may scatter rust and other pathogens throughout a plant population, the mechanism by which this occurs has not been explored, until now.
Acoustic-gravity waves can be generated by underwater earthquakes, explosions and landslides, as well as by surface waves and meteorites. A single one of these waves can stretch tens or hundreds of kilometers, and travel at depths of hundreds or thousands of meters below the ocean surface, transferring energy from the upper surface to the seafloor, and across the oceans. Acoustic-gravity waves often precede a tsunami or rogue wave.
As a grape slowly dries and shrivels, its surface creases, ultimately taking on the wrinkled form of a raisin. Similar patterns can be found on the surfaces of other dried materials, as well as in human fingerprints. While these patterns have long been observed in nature, and more recently in experiments, scientists have not been able to come up with a way to predict how such patterns arise in curved systems, such as microlenses.
Human taste receptors are specialized to distinguish several distinct compounds: sugars taste sweet, salts taste salty, and acidic compounds taste sour. Now a new study from Massachusetts Institute of Technology finds that the worm Caenorhabditis elegans has taken its powers of detection a step further: The worm can taste hydrogen peroxide, triggering it to stop eating the potentially dangerous substance.
Every undergraduate computer science major takes a course on data structures, which describes different ways of organizing data in a computer’s memory. Every data structure has its own advantages: Some are good for fast retrieval, some for efficient search, some for quick insertions and deletions and so on. Today, hardware manufacturers are making computer chips faster by giving them more cores, or processing units.
Quantum computers are experimental devices that promise exponential speedups on some computational problems. Where a bit in a classical computer can represent either a 0 or a 1, a quantum bit, or qubit, can represent 0 and 1 simultaneously, letting quantum computers explore multiple problem solutions in parallel. But such “superpositions” of quantum states are, in practice, difficult to maintain.
After undergoing surgery to remove diseased sections of the colon, up to 30% of patients experience leakage from their sutures, which can cause life-threatening complications. Many efforts are under way to create new tissue glues that can help seal surgical incisions and prevent such complications; now, a new study reveals that the effectiveness of such glues hinges on the state of the tissue in which they are being used.
Research combining experimental work and detailed molecular simulations has revealed, for the first time, the complex role that water plays in collagen. The new analysis reveals an important mechanism that had never been observed before: Adding even small amounts of water to, or removing water from, collagen in tendons can generate surprisingly strong forces, as much as 300 times stronger than the forces generated by muscles.
Optimization algorithms are everywhere in engineering. Among other things, they’re used to evaluate design tradeoffs, to assess control systems and to find patterns in data. One way to solve a difficult optimization problem is to first reduce it to a related but much simpler problem, then gradually add complexity back in, solving each new problem in turn and using its solution as a guide to solving the next one.
Carbon sequestration promises to address greenhouse gas emissions by capturing carbon dioxide from the atmosphere and injecting it deep below the Earth’s surface, where it would permanently solidify into rock. The U.S. Environmental Protection Agency estimates that current carbon sequestration technologies may eliminate up to 90% of carbon dioxide emissions from coal-fired power plants.
Patients with sickle cell disease often suffer from painful attacks known as vaso-occlusive crises, during which their sickle-shaped blood cells get stuck in tiny capillaries, depriving tissues of needed oxygen. Blood transfusions can sometimes prevent such attacks, but there are currently no good ways to predict when a vaso-occlusive crisis, which can last for several days, is imminent.
The human brain’s complexity makes it extremely challenging to study; not only because of its sheer size, but also because of the variety of signaling methods it uses simultaneously. Conventional neural probes are designed to record a single type of signaling, limiting the information that can be derived from the brain at any point in time. Now researchers at Massachusetts Institute of Technology may have found a way to change that.
A new study from Massachusetts Institute of Technology reveals one reason why people who suffer from chronic inflammatory diseases such as colitis have a higher risk of mutations that cause cancer. The researchers also found that exposure to DNA-damaging chemicals after a bout of inflammation boosts these mutations even more, further increasing cancer risk.
Imagine that you could tell your phone that you want to drive from your house in Boston to a hotel in upstate New York, that you want to stop for lunch at an Applebee’s at about 12:30, and that you don’t want the trip to take more than four hours. Then imagine that your phone tells you that you have only a 66% chance of meeting those criteria.
Beginning with the invention of the first microscope in the late 1500s, scientists have been trying to peer into preserved cells and tissues with ever-greater magnification. The latest generation of so-called “super-resolution” microscopes can see inside cells with resolution better than 250 nm.
Meteors that have crashed to Earth have long been regarded as relics of the early solar system. These craggy chunks of metal and rock are studded with chondrules, tiny, glassy, spherical grains that were once molten droplets. Scientists have thought that chondrules represent early kernels of terrestrial planets.
Sometimes the response to the outbreak of a disease can make things worse. The ability to anticipate when such overreactions might occur could help public health officials take steps to limit the dangers. Now a new computer model could provide a way of making such forecasts, based on a combination of data collected from hospitals, social media and other sources.
Ever notice an earthy smell in the air after a light rain? Now scientists believe they may have identified the mechanism that releases this aroma, as well as other aerosols, into the environment. Using high-speed cameras, the researchers observed that when a raindrop hits a porous surface, it traps tiny air bubbles at the point of contact.
The immune system is a complex network of many different cells working together to defend against invaders. Successfully fighting off an infection depends on the interactions between these cells. A new device developed by Massachusetts Institute of Technology engineers offers a much more detailed picture of that cellular communication.
For household robots ever to be practical, they’ll need to be able to recognize the objects they’re supposed to manipulate. But while object recognition is a highly studied topic in artificial intelligence, even the best object detectors still fail much of the time. Researchers at MIT believe that household robots should take advantage of their mobility and their relatively static environments to make object recognition easier.
A team of researchers has built an array of light detectors sensitive enough to register the arrival of individual light particles, or photons, and mounted them on a silicon optical chip. Such arrays are crucial components of devices that use photons to perform quantum computations.
In 2007, Google unleashed a fleet of cars with roof-mounted cameras to provide street-level images of roads around the world. Now Massachusetts Institute of Technology spinout Essess is bringing similar “drive-by” innovations to energy efficiency in homes and businesses.
Lead sulfide nanocrystals suitable for solar cells have a nearly one-to-one ratio of lead to sulfur atoms, but Massachusetts Institute of Technology (MIT) researchers discovered that to make uniformly sized quantum dots, a higher ratio of lead to sulfur precursors—24 to 1—is better.