Researchers at Los Alamos National Laboratory are investigating the complex relationships between the spread of the HIV virus in a population (epidemiology) and the actual, rapid evolution of the virus (phylogenetics) within each patient’s body. The team models the uninfected population using traditional differential equations on the computer; this is done for computational speed, because an agent-based component is much more demanding.
“Function follows form” might have been written to describe proteins, as the M. C. Escher-esque folds and twists of nature’s workhorse biomolecules enables each to carry out its specific responsibilities. X-ray protein crystallography determines protein structures by creating a diffraction pattern of dots that can be reconstructed by computer into a 3-D model.
One of the world’s largest dinosaurs has been digitally reconstructed by experts from The Univ. of Manchester allowing it to take its first steps in over 94 million years. The Manchester team, working with scientists in Argentina, were able to laser scan a 40-m-long skeleton of the vast Cretaceous Argentinosaurus dinosaur. Then using an advanced computer modeling technique they recreated its walking and running movements.
In a pair of studies that exploit the genetic sequencing of the “missing link” cold virus, rhinovirus C, scientists at the Univ. of Wisconsin-Madison have constructed a 3-D model of the pathogen that shows why there is no cure yet for the common cold. The new cold virus model was built in silico, drawing on advanced bioinformatics and the genetic sequences of 500 rhinovirus C genomes, which provided 3-D coordinates of the viral capsid.
Scientists in Germany have developed a mathematical model for a type of microscopic test lab that could provide new and deeper insight into the world of quantum particles. The new test system will enable the simultaneous study of one hundred light quanta, or photons, and their quantum entanglements. This is a far greater number than was previously possible.
A new physics model developed at Rensselaer Polytechnic Institute shows that changing air flows can transfer energy to wind turbines from both above and below the blades. According to the researchers, many wind turbine array studies overlook the fact that important airflow changes occur inside the array.
A new study set out to use numerical simulations to validate previous theoretical predictions describing materials exhibiting so-called antiferromagneting characteristics. A recently discovered theory shows that the ordering temperature depends on two factors—namely the spin-wave velocity and the staggered magnetization. The simulations match these theoretical predictions.
A research team including a Penn State chemical engineer was recently awarded a $3.9 million National Science Foundation grant to understand how blue-green algae convert nitrogen into oxygen. The objective is to learn how to "transplant" the nitrogen fixing capability of one species to another.
Around 3% of all plants use an advanced form of photosynthesis, which allows them to capture more carbon dioxide, use less water, and grow more rapidly. This phenomenon had been a mystery, but researchers have used a mathematical analysis to uncover a number of tiny changes in the plants' physiology that allow them to grow more quickly, using a third as much water as other plants and capturing around 13 times more carbon dioxide.
Enhanced growth of Earth's leafy greens during the 20th century has significantly slowed the planet's transition to being red-hot, according to the first study to specify the extent to which plants have prevented climate change since pre-industrial times. Researchers have found that land ecosystems have kept the planet cooler by absorbing billions of tons of carbon, especially during the past 60 years.
Three U.S.-based scientists won the 2013 Nobel Prize in chemistry for developing powerful computer models that others can use to understand complex chemical interactions and create new drugs. Research in the 1970s by Martin Karplus, Michael Levitt and Arieh Warshel has helped scientists develop programs that unveil chemical processes such as the purification of exhaust fume or photosynthesis, the Royal Swedish Academy of Sciences said.
A tag team of two bacteria, one of them genetically modified, has a good chance to reduce or even eliminate the deadly disease African trypanosomiasis, or sleeping sickness, researchers at Oregon State Univ. conclude in a recent mathematical modeling study. African trypanosomiasis, caused by a parasite carried by the tsetse fly, infects 30,000 people in sub-Saharan Africa each year and is almost always fatal without treatment.
Electrical currents born from thunderstorms are able to flow through the atmosphere and around the globe, causing a detectable electrification of the air even in places with no thunderstorm activity. But a good understanding of atmospheric conductivity has eluded scientists. Now, a research team in Colorado has developed a global electric circuit model by adding an additional layer to a climate model.
Since the discovery of the Van Allen radiation belts in 1958, space scientists have believed these belts encircling the Earth consist of two doughnut-shaped rings of highly charged particles. In February of 2013, a team of scientists reported the surprising discovery of a previously unknown third radiation ring. In new research, scientists have successfully modeled and explained the unprecedented behavior of this third ring.
Human influences have directly impacted the latitude/altitude pattern of atmospheric temperature. That is the conclusion of a new report by scientists from Lawrence Livermore National Laboratory and six other scientific institutions. The research compares multiple satellite records of atmospheric temperature change with results from a large, multimodel archive of simulations.
Just as wind turbines tap into the energy of flowing air to generate electricity, hydrokinetic devices produce power from moving masses of water. Engineers in Spain have performed a computer simulation to determine the optimal configuration of a system produced by a Norwegian company to enable it to extract the maximum amount of energy from any given current.
Electronic devices with touchscreens rely on transparent conductors made of indium tin oxide, or ITO. But cost and the physical limitations of this material are limiting progress in developing flexible touchscreens. A research collaboration between the Univ. of Pennsylvania and Duke Univ. is exploring the use of nanowires to replace ITO, and are using simulation tools to determine how they might work.
The amount of raw materials needed to sustain the economies of developed countries is significantly greater than present indicators suggest, a new Australian study has revealed. Using a new modeling tool and more comprehensive indicators, researchers Australia were able to map the flow of raw materials across the world economy with unprecedented accuracy to determine the true “material footprint” of 186 countries over a two-decade period.
Global warming may further lessen the likelihood of the freak atmospheric steering currents that last year shoved Superstorm Sandy due west into New Jersey, a new study says. But the study's authors said the once-in-700-years path was only one factor in the $50 billion storm. They say other variables such as sea level rise and stronger storms will worsen with global warming and outweigh changes in steering currents predicted by models.
Quantum point contacts in electrical circuits are narrow constrictions that can impede the passage of electrons in unexpected ways. Using a combination of experimental measurements and numerical modeling, physicists have recently provided the first detailed microscopic explanation of the associated conductance anomalies.
Research by Harvard Univ. environmental scientists brings bad news to the western U.S., where firefighters are currently battling dozens of fires in at least 11 states. A new model predicts wildfire seasons by 2050 will be three weeks longer, up to twice as smoky and will burn a wider area in the western U.S.
Since the genetic code’s discovery in the 1960s, researchers have wondered: How is it that a near-optimal code became so universal? To address this question, the researchers created a model of genetic code evolution in which multiple “translating” RNAs and “genomic” RNAs competed for survival. The approach revealed phenomena that offers new insights into how RNA signaling likely developed into the modern genetic code.
When a beating heart slips into an irregular, life-threatening rhythm, the treatment is well known: deliver a burst of electric current from a pacemaker or defibrillator. But because the electricity itself can cause pain, tissue damage and other serious side-effects, a Johns Hopkins-led research team wants to use laboratory data and an intricate computer model replace these jolts with a kinder, gentler remedy: light.
Computer models are used to inform policy decisions about energy, but existing models are generally “black boxes” that don’t show how they work, making it impossible for anyone to replicate their findings. Researchers from North Carolina State Univ. have developed a new open-source model and are sharing the data they put into it, to allow anyone to check their work.
All living things must obey the laws of physics, including the second law of thermodynamics. Highly ordered cells and organisms appear to contradict this principle, but they actually do conform because they generate heat that increases the universe’s overall entropy. A Massachusetts Institute of Technology physicist mathematically modeled the replication of E. coli bacteria and found that the process is nearly as efficient as possible.