Using the quantitative approach of physicists, biologists in Israel have developed experimental tools to measure precisely the bacterial response to antibiotics. Their mathematical model of the process has led them to hypothesize that a daily three-hour dose would enable the bacteria to predict delivery of the drug, and go dormant for that period in order to survive.
Aerospace engineers from the Univ. of Illinois, Urbana-Champaign are using the National Science Foundation-supported Stampede supercomputer to explore how jets in general, like those on modern aircraft and inside the human body, generate noise. This is important because no simple explanation of how jets generate noise is currently available, and without this understanding making jets quieter is difficult.
Concentrating solar power (CSP) could supply a large fraction of the power supply in a decarbonized energy system, according to a new study of the technology and its potential practical application. For this research, scientists simulated the construction and operation of CSP systems in four regions around the world, taking into account weather variations, plant locations, electricity demand, and costs.
Organic semiconductors have tremendous potential for complementing conventional, inorganic semiconductors, but energy losses or barriers at the connection interfaces have blocked development efforts. Physicists have now implemented a detailed electrostatic model which is capable of covering the full phenomenological range of interfacial energy-level alignment regimes within a single, consistent framework.
Seemingly ordinary, water has quite puzzling behavior. Why, for example, does ice float when most liquids crystallize into dense solids that sink? Using a computer model to explore water as it freezes, a team at Princeton Univ. has found that water's weird behaviors may arise from a sort of split personality: At very cold temperatures and above a certain pressure, water may spontaneously split into two liquid forms.
It’s likely that most of the large impact craters on Earth have already been discovered and that others have been erased, according to a new calculation by a pair of Purdue Univ. graduate students. Although it's known that natural processes erase craters fairly quickly from the Earth's surface, this model was the first to quantify how many craters have likely been erased.
Inspired by anomalies that arise in certain mathematical equations, researchers have demonstrated a laser system that paradoxically turns off when more power is added rather than becoming continuously brighter. The finding could lead to new ways to manipulate the interaction of electronics and light, an important tool in modern communications networks and high-speed information processing.
A new study of supermassive black holes at the centers of galaxies has found magnetic fields play an impressive role in the systems’ dynamics. In fact, in dozens of black holes surveyed, the magnetic field strength matched the force produced by the black holes’ powerful gravitational pull, says a team of scientists.
Imagine a tower that builds itself into the desired structure only by choosing the appropriate bricks. Absurd, but in the nano world self-assembly is now a common practice for forming structures. Researchers in Austria have been investigating how they can control the ordering of self-assembling structures and discovered how to switch the assembly process on and off.
Bacteria use threadlike appendages, called pili, to creep along a surface, and some disease-causing microbes extend pili in all directions to move. But until now researchers have been unable to explain why bacteria like these are able to travel in a straight line consistently. A new model developed to describe this movement shows that bacteria do not act as randomly as they appear to when moving.
According to new research from Sweden, two aircraft engine concepts, a geared turbofan and an open rotor, can enable a significant reduction to aircraft fuel consumption. With an open rotor, the potential reduction is 15%. An open rotor engine generates most of the thrust from two counter-rotating propellers instead of a ducted fan. This enables a larger engine diameter and a higher propulsive efficiency.
In a typical wind farm, the wind turbine located in the wakes of upstream turbines would experience a much different surface wind compared to the ones located upwind due to wake interferences. Scientists at Iowa State Univ. have completed a study on the effects of these relative rotation directions, using two tandem wind turbines as a model. They found a big difference in performance between co-rotating and counter-rotating turbines.
A small group of engineers at Ohio State Univ. combined laboratory testing and computational modeling conducted at the Ohio Supercomputer Center to determine the relationship between the mechanical function, structural design and material properties of the Allegheny mound ant, a creature that can lift objects many times heavier than its own body. The study could solve the mystery of how this structure actually works.
In an effort to better understand what persuades people to buy photovoltaic systems for their homes, researchers at Sandia National Laboratories are gathering data on consumer motivations that can feed computer models and thus lead to greater use of solar energy. A primary goal of the project is to help increase the nation’s share of solar energy in the electricity market from its current share of less than .05% to at least 14% by 2030.
Clouds are the largest source of uncertainty in present climate models. Much of the uncertainty surrounding clouds' effect on climate stems from the complexity of cloud formation. New research from scientists at the Cosmics Leaving OUtdoor Droplets (CLOUD) experiment at CERN sheds light on new-particle formation, which is the very first step of cloud formation and a critical component of climate models.
There is an optimum size for electrical networks if what is being considered is the risk of a blackout. This is the conclusion reached by a scientific study by researchers in Spain and the U.S. The study, which analyzed the dynamics of these complex infrastructures, found that an optimum adequate size exists that helps guarantee correct functioning of an electrical network.
Move over, Matrix, astronomers at MIT/Harvard-Smithsonian Center for Astrophysics and the Heidelberg Institute for Theoretical Studies in Germany have done you one better. They have created the first realistic virtual universe using a computer simulation called "Illustris." Illustris can recreate 13 billion years of cosmic evolution in a cube 350 million light-years on a side with unprecedented resolution.
Sprites are an optical phenomenon that occur above thunderstorms, about 37 to 56 miles above the Earth. Atmospheric sprites have been known for nearly a century, but their origins were a mystery. Now, a team of researchers has evidence that sprites form at plasma irregularities and may be useful in remote sensing of the lower ionosphere.
Farmers optimize crop production on their own lands by rotating crops, or testing soils to choose the right amount of fertilizers to apply. But is it possible to optimize production across a much bigger area, such as the eastern U.S.? That’s the question a team of U.S. Dept. of Agriculture scientists has begun to tackle by developing a sophisticated new modeling tool.
Engineering simulation software provider ANSYS announced Thursday that it has acquired SpaceClaim Corp. for a purchase price of $85 million in cash. SpaceClaim is a developer of fast, intuitive 3-D direct modeling software for engineers, and has partnered with ANSYS in the past to offer customers ANSYS SpaceClaim Direct Modeler.
A team of computer scientists, mathematicians and geophysicists in Germany have optimized the SeisSol earthquake simulation software at Leibniz Supercomputing Center to push its performance beyond the one petaflop/sec mark, which equates to one quadrillion floating point operations per second. SeisSol is used to investigate rupture processes and seismic waves.
In today’s fast-paced markets, engineers are continuously challenged to deliver products that meet market demand, improve operational efficiency and exceed customer expectations. Multiphysics simulation is an essential component of the product design workflow for creating innovative designs, especially when building prototypes becomes impractical or when taking actual measurements is not possible.
The stakes are incredibly high for the safety and compliance efforts of today’s oil and gas industry. Engineers and crews must be trained for increasingly complex processes and procedures used aboard drilling rigs and production platforms. The consequences of inadequate training during oil production can be disastrous to both operator crews and the environment.
Scientists have created a detailed, three-dimensional wiring diagram of the mouse brain. That should help researchers seek clues about how the human brain works in health and disease.
A mathematical model created by Penn State Univ. researchers can predict with more than 90% accuracy the blood glucose levels of individuals with type 1 diabetes up to 30 min in advance of imminent changes in their levels, which is plenty of time to take preventative action. The model was estimated by the extended Kalman filtering technique and accounts for time-varying changes in glucose kinetics due to insulin and meal intake.