LAB REPORT
Science and Technology Making Headlines
May 19, 2017
Getting to the heart of it
Prescription drugs have enabled millions of Americans with chronic medical conditions to live longer and have more fulfilling lives, but many promising new drugs never make it to the human trials stage due to the potential for cardiac toxicity.
Through “heart-on-a-chip” technology — modeling a human heart on an engineered chip and measuring the effects of compound exposure on functions of heart tissue using microelectrodes — Lawrence Livermore researchers hope to decrease the time needed for new drug trials and ensure potentially lifesaving drugs are safe and effective while reducing the need for human and animal testing.
Tracking nutrients through the body
Lawrence Livermore researchers have developed a laser-based tabletop device to measure carbon-14 (radiocarbon) in biological systems.
In biological systems, carbon-14 can be used as a biochemical tracer to track micro-doses of nutrients, toxins and therapeutics in humans and animals. For example, the carbon-14 can be tacked on to a vitamin. When a human ingests the vitamin, researchers can track how much of the vitamin metabolizes and how much is excreted through urine analysis.
Typically, acclerator mass spectrometry is used for this type of research, however, cavity ring-down spectroscopy (CRDS) has emerged as a laser-based method capable of carbon-14 measurements. Livermore scientists developed a CRDS spectrometer capable of measuring carbon-14 for biology research.
Cloudy outlook on global warming
There are several factors, including natural and human, that influence climate change. One of the harder influences to pin down has been changes in clouds. As the world warms, more water vapor ends up in the atmosphere — and water vapor is an important greenhouse gas. But the bright, low clouds that water vapor can form reflect sunlight, shading and cooling the Earth.
It turns out the net result of increased water vapor enhances warming rather than limiting it. A new study by Lawrence Livermore National Laboratory’s Chen Zhou, Mark Zelinka and Stephen Klein reveals an interesting interaction that makes this even more complicated.
It’s not enough to figure out what clouds will do in general — there’s not some single number that you can get to stand in for clouds. Instead, there are spatial patterns to clouds’ effects, and they vary over time. This has some interesting implications for understanding the last few decades and what’s coming in the future.
Scenic boom
Lawrence Livermore National Laboratory physicist Greg Spriggs has an important mission. He’s working with film preservation expert Jim Moye to save decades-old films of nuclear blasts that are among the last best sources of real-world information about nuclear explosions.
From 1945 to 1963, the U.S. detonated 210 nuclear devices in the air. Scientists captured the massive fireballs and mushroom clouds on camera — preserving the data in at least 10,000 films. The films were then analyzed to determine key details like the energy unleashed by the blast, or its yield.
Those measurements, however, were done without computers — and Spriggs discovered that some of that data wasn’t quite right. So he decided to find all 10,000 of those films to reanalyze them from scratch. Lawrence Livermore recently published 60 of the declassified nuclear test films on YouTube.
Pushing paper toward efficiency
If you had to name the industries in the United States that use the most energy, paper manufacturing probably wouldn't immediately come to mind. In fact, the paper-making industry ranks third among the country's largest energy users, behind only petroleum-refining and chemical production, according to the U.S. Energy Information Administration.
Researchers at Lawrence Livermore and Lawrence Berkeley national laboratories are using the national labs' supercomputing capabilities to look at more energy efficient and cost-saving ways to make paper, targeting "wet-pressing," the stage where water is removed by mechanical pressure from the wood pulp into press felts that help soak up water before it is sent through a drying process.
The researchers hope to develop a model for flow and deformation of the wet porous paper during the process, saving both energy and money. The project is one of the seedlings for the Department of Energy's HPC4Mfg initiative, a multi-lab effort headed by LLNL to use high-performance computing to address complex challenges in U.S. manufacturing.