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Given a graph G with weight function w and an acyclic edge subset E', the partial inverse spanning tree problem on (G, w; E') is to find a new weight function w* so that E' can be extended to a maximu...
Asked to name his favorite tree, Paul W. Meyer, the former director of Penn’s Morris Arboretum, likens the task to “asking a parent to name their favorite child.”
Conformal invariance of critical lattice models in two-dimensional has been vigorously studied for decades. The first example where the conformal invariance was rigorously verified was the planar unif...
By reading between the lines of tree rings, U.S. National Science Foundation-funded researchers at the University of Arizona reconstructed what happened in Alaska the year the Laki Volc...
Scientists have found that while all regions of the country can expect an earlier start to the growing season as temperatures rise, the trend is likely to become more variable year-over-year in hotter...
Sloths, which once roamed the Americas, ranged from tiny, cat-sized animals that lived in trees to massive ground sloths that may have weighed up to six tons. The only species we know today are two-to...
Researchers have for the first time traced the roots of crabs, lobsters and shrimp to create the family tree of crustaceans people love to eat.The tree shows the 450-million-year evolution of these 10...
The presented experiment investigates the potential of Multispectral Laser Scanning (MLS) point clouds for single tree species classification. The basic idea is to simulate a MLS sensor by combining t...
A new study finds that viruses share some genes exclusively with cells that are not their hosts. The study, reported in the journal Frontiers in Microbiology, adds to the evidence that viruses swap ge...
With all the discussion about global climate change effects, new research shows that another kind of climate is an important factor in regional pinyon pine tree recovery after drought events – the mic...
Polypterids are weird and puzzling African fish that have perplexed biologists since they were discovered during Napoleon's expedition to Egypt in the late 1700s.Often called living fossils, these eel...
Since the mid-1990s, when the first planet around another sun-like star was discovered, astronomers have been amassing what is now a large collection of exoplanets—nearly 3,500 have been confirmed so ...
Reshaping Darwin’s Tree of Life     Reshaping  Darwin’s Tree  Life       2017/7/21
In 1859, Charles Darwin included a novel tree of life in his trailblazing book on the theory of evolution, On the Origin of Species. Now, scientists from Rutgers University-New Brunswick and their int...
Earth’s earliest primates dwelled in treetops, not on the ground, according to an analysis of a 62-million-year-old partial skeleton discovered in New Mexico — the oldest-known primate skeleton.The sk...
The citizen science program to supplement authoritative data in tree inventory has been well implemented in various countries. However, there is a lack of study that assesses correctness and accuracy ...

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