Given the chance, women are more likely than men to opt out of a request to give a charitable donation, a group of economists have found.
The issue of which gender is more generous has been debated for years. A new field experiment conducted by scholars at the University of Chicago and University of California, Berkeley shows that when it’s easy to avoid making a donation, such as not responding to a door-to-door solicitor, women are less likely than men to give. (more…)
Berkeley Lab bioscientists and their colleagues decipher a far-reaching problem in computer simulations
Because modern computers have to depict the real world with digital representations of numbers instead of physical analogues, to simulate the continuous passage of time they have to digitize time into small slices. This kind of simulation is essential in disciplines from medical and biological research, to new materials, to fundamental considerations of quantum mechanics, and the fact that it inevitably introduces errors is an ongoing problem for scientists.
Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have now identified and characterized the source of tenacious errors and come up with a way to separate the realistic aspects of a simulation from the artifacts of the computer method. The research was done by David Sivak and his advisor Gavin Crooks in Berkeley Lab’s Physical Biosciences Division and John Chodera, a colleague at the California Institute of Quantitative Biosciences (QB3) at the University of California at Berkeley. The three report their results in Physical Review X. (more…)
AUSTIN, Texas — Landscapes with large amounts of paved roads and impervious construction have lower numbers of ground-nesting bumblebees, which are important native pollinators, a study from The University of Texas at Austin and the University of California, Berkeley shows.
The study suggests that management strategies that reduce the local use of pavement and increase natural habitat within the landscape could improve nesting opportunities for wild bees and help protect food supplies around the word. (more…)
Berkeley Lab Researchers Develop New Technique for Heterogenizing Homogenous Nano Catalysts
Catalysts are substances that speed up the rates of chemical reactions without themselves being chemically changed. Industrial catalysts come in two main types – heterogeneous, in which the catalyst is in a different phase from the reactants; and homogeneous, in which catalyst and the reactants are in the same phase. Heterogeneous catalysts are valued for their sustainability because they can be recycled. Homogeneous catalysts are valued for their product selectivity as their properties can be easily tuned through relatively simple chemistry.
Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have combined the best properties of both types of industrial catalysts by encapsulating nanoclusters of a metallic heterogeneous catalyst within the branched arms of the molecules known as dendrimers. (more…)
Analysis of data from the National Science Foundation’s South Pole Telescope, for the first time, more precisely defines the period of cosmological evolution when the first stars and galaxies formed and gradually illuminated the universe. The data indicate that this period, called the epoch of reionization, was shorter than theorists speculated — and that it ended early.
“We find that the epoch of reionization lasted less than 500 million years and began when the universe was at least 250 million years old,” said Oliver Zahn, a postdoctoral fellow at the Berkeley Center for Cosmological Physics at the University of California, Berkeley, who led the study. “Before this measurement, scientists believed that reionization lasted 750 million years or longer, and had no evidence as to when reionization began.” (more…)
Researchers from North Carolina State University have found a way to create much slimmer thin-film solar cells without sacrificing the cells’ ability to absorb solar energy. Making the cells thinner should significantly decrease manufacturing costs for the technology.
“We were able to create solar cells using a ‘nanoscale sandwich’ design with an ultra-thin ‘active’ layer,” says Dr. Linyou Cao, an assistant professor of materials science and engineering at NC State and co-author of a paper describing the research. “For example, we created a solar cell with an active layer of amorphous silicon that is only 70 nanometers (nm) thick. This is a significant improvement, because typical thin-film solar cells currently on the market that also use amorphous silicon have active layers between 300 and 500 nm thick.” The “active” layer in thin-film solar cells is the layer of material that actually absorbs solar energy for conversion into electricity or chemical fuel. (more…)
Berkeley Lab researchers use an ultrafast laser to better understand high-temperature superconductors
Superconductivity, in which electric current flows without resistance, promises huge energy savings – from low-voltage electric grids with no transmission losses, superefficient motors and generators, and myriad other schemes. But such everyday applications still lie in the future, because conventional superconductivity in metals can’t do the job.
Although they play important roles in science, industry, and medicine, conventional superconductors must be maintained at temperatures a few degrees above absolute zero, which is tricky and expensive. Wider uses will depend on higher-temperature superconductors that can function well above absolute zero. Yet known high-temperature (high-Tc) superconductors are complex materials whose electronic structures, despite decades of work, are still far from clear. (more…)
A safe haven could be out of reach for 9 percent of the Western Hemisphere’s mammals, and as much as 40 percent in certain regions, because the animals just won’t move swiftly enough to outpace climate change.
For the past decade scientists have outlined new areas suitable for mammals likely to be displaced as climate change first makes their current habitat inhospitable, then unlivable. For the first time a new study considers whether mammals will actually be able to move to those new areas before they are overrun by climate change. Carrie Schloss, University of Washington research analyst in environmental and forest sciences, is lead author of the paper out online the week of May 14 in the Proceedings of the National Academy of Sciences. (more…)
