Tag Archives: mathematical model

Mathematical framework: How a wrinkle becomes a crease

Kyung-Suk Kim and Mazen Diab have worked out the mathematics of how wrinkles form in solid materials under compression — and how, under more compression, those wrinkles can become creases. The mathematics of wrinkles and creases could help in the design of flexible electronic circuits, artificial skin, and soft robotic grips and may help explain brain injuries due to compression.

PROVIDENCE, R.I. [Brown University] — Wrinkles, creases and folds are everywhere in nature, from the surface of human skin to the buckled crust of the Earth. They can also be useful structures for engineers. Wrinkles in thin films, for example, can help make durable circuit boards for flexible electronics. (more…)

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Maths predicts rise and fall of empires

Researchers have developed a new mathematical model that accurately describes the evolution of ancient empires.

The computer model can predict with 65% accuracy where and when the largest complex societies arose in human history.

The research, which suggests that intense warfare is the evolutionary driver of large complex societies, is published in the journal Proceedings of the National Academy of Sciences (PNAS). It was carried out by researchers from the University of Exeter in collaboration with University of Connecticut and the National Institute for Mathematical and Biological Synthesis (NIMBioS) in the US. (more…)

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Reconcilable Differences: Study Uncovers the Common Ground of Scientific Opposites

Searching for common elements in seemingly incompatible scientific theories may lead to the discovery of new ones that revolutionize our understanding of the world.

Such is the idea behind a mathematical framework Princeton University researchers developed that strips away the differences between scientific laws and theories to reveal how the ideas are compatible. In a recent report in the journal Physical Review Letters, the authors explain how the mathematical model finds common ground between the famously at-odds physics equations that govern classical and quantum mechanics. (more…)

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Climate Change Could Increase Levels of Avian Influenza in Wild Birds

ANN ARBOR, Mich.— Rising sea levels, melting glaciers, more intense rainstorms and more frequent heat waves are among the planetary woes that may come to mind when climate change is mentioned. Now, two University of Michigan researchers say an increased risk of avian influenza transmission in wild birds can be added to the list.

Population ecologists Pejman Rohani and Victoria Brown used a mathematical model to explore the consequences of altered interactions between an important species of migratory shorebird and horseshoe crabs at Delaware Bay as a result of climate change. (more…)

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It’s in the Genes: Research Pinpoints How Plants Know When to Flower

Scientists believe they’ve pinpointed the last crucial piece of the 80-year-old puzzle of how plants “know” when to flower.

Determining the proper time to flower, important if a plant is to reproduce successfully, involves a sequence of molecular events, a plant’s circadian clock and sunlight.

Understanding how flowering works in the simple plant used in this study – Arabidopsis – should lead to a better understanding of how the same genes work in more complex plants grown as crops such as rice, wheat and barley, according to Takato Imaizumi, a University of Washington assistant professor of biology and corresponding author of a paper in the May 25 issue of the journal Science. (more…)

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Plastic Pollution

Wind pushes plastics deeper into oceans, driving trash estimates up

Decades of research into how much plastic litters the sea may have only skimmed the surface. A new study reveals that wind drives confetti-sized pieces of plastic debris deeper underwater than previously believed, more than doubling earlier estimates of the pollutant’s presence in oceans.

“In windy conditions the traditional approach to measuring plastic marine debris captures only a small fraction of plastic pieces,” said Tobias Kukulka, assistant professor of physical ocean science and engineering in the University of Delaware’s College of Earth, Ocean, and Environment. “Our study helps to better understand how much plastic there is and where, as well as the complexity of the ocean dynamics at work.” (more…)

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Images Capture Split Personality of Dense Suspensions

Stir lots of small particles into water, and the resulting thick mixture appears highly viscous. When this dense suspension slips through a nozzle and forms a droplet, however, its behavior momentarily reveals a decidedly non-viscous side. University of Chicago physicists recorded this surprising behavior in laboratory experiments using high-speed photography, which can capture action taking place in one hundred-thousandths of a second or less.

UChicago graduate student Marc Miskin and Heinrich Jaeger, the William J. Friedman and Alicia Townsend Friedman Professor in Physics, expected that the dense suspensions in their experiments would behave strictly like viscous liquids, which tend to flow less freely than non-viscous liquids. Viscosity certainly does matter as the particle-laden liquid begins to exit the nozzle, but not at the moment where the drop’s thinning neck breaks in two. (more…)

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‘Explorers’ Use Uncertainty And Specific Area of Brain

*As they try to find the best reward among options, some people explore based on how uncertain they are about the outcome of the options.  Those who employ that thought process, unlike people who use other strategies, uniquely harness the computational power of the rostrolateral prefrontal cortex, a new study finds.*

PROVIDENCE, R.I. [Brown University] — Life shrouds most choices in mystery. Some people inch toward a comfortable enough spot and stick close to that rewarding status quo. Out to dinner, they order the usual. Others consider their options systematically or randomly. But many choose to grapple with the uncertainty head on. “Explorers” order the special because they aren’t sure they’ll like it. It’s a strategy of maximizing rewards by discovering whether as yet unexplored options might yield better returns. In a new study, Brown University researchers show that such explorers use a specific part of their brain to calculate the relative uncertainty of their choices, while non-explorers do not. (more…)

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