Madison - A fundamental question about how sugar units are strung together into long carbohydrate chains has also pinpointed a promising way to target new medicines against tuberculosis.
Working with components of the tuberculosis bacterium, researchers from the University of Wisconsin-Madison identified an unusual process by which the pathogen builds an important structural carbohydrate. In addition to its implications for human health, the mechanism offers insight into a widespread but poorly understood basic biological function - controlling the length of carbohydrate polymers.
Science & Technology
Archaeologists have used stone tools to answer many questions about human ancestors in both the distant and near past and now they are analyzing the origin of obsidian flakes to better understand how people settled and interacted in the inhospitable Kuril Islands.
Using X-ray fluorescence spectrometers, archaeologists from the University of Washington and the Smithsonian Institution have found the origin of 131 flakes of obsidian, a volcanic glass. These small flakes were discarded after stone tools were made from obsidian and were found at 18 sites on eight islands in the Kurils. The flakes were found with other artifacts that were dated over a time period spanning about 1,750 years, from 2500 to 750 years before the present.
Using X-ray fluorescence spectrometers, archaeologists from the University of Washington and the Smithsonian Institution have found the origin of 131 flakes of obsidian, a volcanic glass. These small flakes were discarded after stone tools were made from obsidian and were found at 18 sites on eight islands in the Kurils. The flakes were found with other artifacts that were dated over a time period spanning about 1,750 years, from 2500 to 750 years before the present.
Implicit stereotypes - thoughts that people may be unwilling to express or may not even know that they have - may have a powerful effect on gender equity in science and mathematics engagement and performance, according to a new study published this week in the Proceedings of the National Academy of Sciences.
The international study involving more than half a million participants in 34 countries revealed that 70 percent harbor implicit stereotypes associating science with males more than with females. Moreover, in countries whose citizens stereotyped most strongly, boys achieved at a higher level in eighth-grade science and math.
Implicit stereotypes may contribute to continuing underachievement and under-participation among girls and women in science compared to their male peers.
The international study involving more than half a million participants in 34 countries revealed that 70 percent harbor implicit stereotypes associating science with males more than with females. Moreover, in countries whose citizens stereotyped most strongly, boys achieved at a higher level in eighth-grade science and math.
Implicit stereotypes may contribute to continuing underachievement and under-participation among girls and women in science compared to their male peers.
© Arizona State University
Pastel colors swirl across Mars, revealing differences in the composition and nature of the surface in this recently taken false-color infrared THEMIS image. Showing an area 31.9 kilometers (19.8 miles) by 88.3 kilometers (54.9 miles) in the southern highlands of Mars, the image is a result of the earlier orbit time for Mars Odyssey and THEMIS. In the image, dark areas mark exposures of relatively cold ground with abundant bare rock, while warmer basaltic sand covers the light blue-green regions. Reddish areas likely have a higher silica content, due either to a different volcanic composition or to weathering.
Pastel colors swirl across Mars, revealing differences in the composition and nature of the surface in this recently taken false-color infrared THEMIS image. Showing an area 31.9 kilometers (19.8 miles) by 88.3 kilometers (54.9 miles) in the southern highlands of Mars, the image is a result of the earlier orbit time for Mars Odyssey and THEMIS. In the image, dark areas mark exposures of relatively cold ground with abundant bare rock, while warmer basaltic sand covers the light blue-green regions. Reddish areas likely have a higher silica content, due either to a different volcanic composition or to weathering.
The maneuver to change Odyssey's orbit began Sept. 30, 2008, and ended June 9, 2009, with a five-and-a-half-minute thruster firing. The rocket burn fixed the spacecraft's track so that THEMIS looks down on the planet at an earlier time of day, 3:45 in the afternoon instead of 5 p.m.
The largest animals ever to have walked the face of the earth may not have been as big as previously thought, reveals a paper published today in the Zoological Society of London's Journal of Zoology.
Scientists have discovered that the original statistical model used to calculate dinosaur mass is flawed, suggesting dinosaurs have been oversized.
Widely cited estimates for the mass of Apatosaurus louisae, one of the largest of the dinosaurs, may be double that of its actual mass (38 tonnes vs. 18 tonnes).
Scientists have discovered that the original statistical model used to calculate dinosaur mass is flawed, suggesting dinosaurs have been oversized.
Widely cited estimates for the mass of Apatosaurus louisae, one of the largest of the dinosaurs, may be double that of its actual mass (38 tonnes vs. 18 tonnes).
Just hand over $15m - first payment, $500,000.
Western Shore - For only $15 million, you could uncover the mystery of Oak Island.
The good news is you'd only have to spend about half a million to begin with because that's about what it would cost to find out if the project's worth pursuing.
Three civil engineering students from McGill University in Montreal were given the assignment to find a way to safely recover any treasure that could be buried at the bottom of the money pit on Oak Island.
Their project received honourable mention from the dean of civil engineering.
The students' professor is Les MacPhie, senior geotechnical engineer at SNC-Lavalin.
Western Shore - For only $15 million, you could uncover the mystery of Oak Island.
The good news is you'd only have to spend about half a million to begin with because that's about what it would cost to find out if the project's worth pursuing.
Three civil engineering students from McGill University in Montreal were given the assignment to find a way to safely recover any treasure that could be buried at the bottom of the money pit on Oak Island.
Their project received honourable mention from the dean of civil engineering.
The students' professor is Les MacPhie, senior geotechnical engineer at SNC-Lavalin.
Rearrangements of all sizes in genomes, genes and exons can result from a glitch in DNA copying that occurs when the process stalls at a critical point and then shifts to a different genetic template, duplicating and even triplicating genes or just shuffling or deleting part of the code within them, said researchers from Baylor College of Medicine in a recent report in the journal Nature Genetics. The report further elucidated the effect of the fork stalling and template switching mechanism involved in some forms of copy number variation.
"I think this is going to make people think very hard about copy number variation with respect to genome evolution, gene evolution and exon shuffling," said Dr. James R. Lupski, vice chair of molecular and human genetics at BCM and senior author of the report.
The mechanism not only represents a newly discovered method by which the genome generates copy number variation among genes, but it also demonstrates that copy number variation can occur at a different time in the life of a cell. DNA replication takes place as the cell is dividing and becoming two - a process known as mitosis.
"I think this is going to make people think very hard about copy number variation with respect to genome evolution, gene evolution and exon shuffling," said Dr. James R. Lupski, vice chair of molecular and human genetics at BCM and senior author of the report.
The mechanism not only represents a newly discovered method by which the genome generates copy number variation among genes, but it also demonstrates that copy number variation can occur at a different time in the life of a cell. DNA replication takes place as the cell is dividing and becoming two - a process known as mitosis.
Jerusalem - Israeli archaeologists said on Sunday they had discovered the largest underground quarry in the Holy Land, dating back to the time of Jesus and containing Christian symbols etched into the walls.
The 4,000-square-meter (yard) cavern, buried 10 meters beneath the desert near the ancient West Bank city of Jericho, was dug about 2,000 years ago and was in use for about half a millennium, archaeologist Adam Zertal said.
The cave's main hall, about three meters tall, is supported by some 20 stone pillars and has a variety of symbols etched into the walls, including crosses dating back to about AD 350 and Roman legionary emblems.
The 4,000-square-meter (yard) cavern, buried 10 meters beneath the desert near the ancient West Bank city of Jericho, was dug about 2,000 years ago and was in use for about half a millennium, archaeologist Adam Zertal said.
The cave's main hall, about three meters tall, is supported by some 20 stone pillars and has a variety of symbols etched into the walls, including crosses dating back to about AD 350 and Roman legionary emblems.
© Ma'an Images
A resident was digging the foundation for an extension on his home when he discovered the cave and alerted Antiquities Police. His home, 300 meters east of the ancient Nativity Church, is located in one of the longest-settled districts of Bethlehem and the site of the cave is believed to be the oldest site uncovered in modern history.
While this week saw NASA successfully launch its Lunar Reconnaissance Orbiter and Lunar Crater Observation and Sensing Satellite missions to the Moon - designed as an exploratory prelude to a human return to our satellite - a senior NASA official claimed on Wednesday that existing plans to venture beyond low-Earth orbit were doomed without extra cash or new technologies.
Speaking at a Washington DC public meeting of the human spaceflight review committee, space shuttle programme manager John Shannon described the Constellation programme, comprising the Ares I and V and the Orion capsule, as a "viable architecture" but one which had "not been funded to the level that we would need to see it through".
He said: "The congressional budget numbers that have been provided to NASA basically took away the lunar programme."
Speaking at a Washington DC public meeting of the human spaceflight review committee, space shuttle programme manager John Shannon described the Constellation programme, comprising the Ares I and V and the Orion capsule, as a "viable architecture" but one which had "not been funded to the level that we would need to see it through".
He said: "The congressional budget numbers that have been provided to NASA basically took away the lunar programme."
Comment: Laura Knight-Jadczyk, in her must-read and well-researched book Through a Glass Darkly: Hidden Masters, Secret Agendas and a Tradition Unveiled sheds some light on Oak Island's mysteries, in a long journey through the continents and the centuries, in search for Truth.